Threshold production of meta-stable bound states of Kaluza Klein excitations in Universal E
生态学专业术语英汉对照2
Ecology 生态学individuals 个体population 种群communities 群落ecosystems 生态系统behavioral ecology 行为生态学physiological ecology 生理生态学evolutionary ecology 进化生态学molecular ecology 分子生态学fitness 适合度natural selection 自然选择adaptation 适应genotype 基因型phenotype 表型phenotypic plasticity 表型可塑性offspring 后代genes 基因nongenetic factors 非遗传因素not inherited 不遗传conditions 条件resources 资源environmental variation 环境变异internal regulation 内调节homeostasis 稳态negative feedback 负反馈tolerance 耐受性temperature 温度not depletable 不能耗掉solar radiation 太阳辐射decouple 退耦niche 生态位habitat 栖息地multidimensional niche space多维生态位空间Fundamental niche基础生态位Realized niche 实际生态位Prey 猎物Foraging 觅食Dimension 轴或维Global wind pattern 地球的风型The circulation of oceans 洋流Rain 降雨Havoc['hævək]灾害Hurricane 飓风Latitude 纬度Irradiance[i'reidiəns,-si]辐射度Summer solstice 夏至Winter solstice 冬至Adiabatic cooling 绝热冷却Scale 尺度Coriolis effect 科里奥利效应Intertropical convergence zone热带辐合带Jet streams 急流Albedo 反照率Gulf stream 墨西哥湾流Lee of a continent 背风面Upwelling 上涌流Adiabatic lapse rate 绝热温度递减率Inversion 逆温Heat of condensation 凝结热Heat 热Temperature profiles温度剖面Relative humidity 相对湿度Saturated water 饱和水water vapor 水蒸汽microclimate 微气候thermal['θə:məl]conductivity 热传导chemical properties of water 水的化学特性penetration of light through water光线穿透水Energy transfer and water phases能量转化和水相Deplete 耗竭Ions 离子Electropositive 正电性的Electronegative 负电性的Beer’s law 比尔定律Heat capacity 热容量Maximum density 最大密度Latent heat of vaporization增发潜热Heat of fusion 溶解热Sublimation 升华Soil water 土壤水Field capacity 田间持水量The uptake of water by roots根对水的吸收Aquatic plants 水生植物Water availability 水的可利用性Plant productivity 植物生产力Permanent wilting point 永久萎焉点Potential evapotranspiration rate潜在蒸发蒸腾速率Capillary pores 毛细管孔隙Resource depletion zone 资源枯竭区Halophytes 盐生植物Water balance in fish 鱼类的水平衡Amphibians 两栖类Water conservation by terrestrial animals 陆生动物的水保持Mammalian 哺乳动物Kidneys 肾脏Bladder 膀胱Beavers 河狸Osmoregulation 渗透调节Countercurrent exchange 逆流调节Hypertonic 高渗的Homeotherms 恒温动物Poikilotherms 变温动物Ectotherms 外温动物Endotherms 内温动物Temperature thresholds 温度阀Mechanisms 机理Enzyme 酶The thermoneutral zone 热中性区Dehydration 脱水Rates of development and growth发育和生长速度Acclimation and acclimatization 驯化和气候驯化Developmental threshold Temperature 发育温度阀Physiological time 生理时间Vernalization 春化Species distribution 物种分布Evolved response 进化反应Mean temperature 平均温度Isotherm 等温线Radiant energy 辐射能Photosynthesis 光合作用Efficiency of radiant energy conversion 辐射能的转换效率Changes in the intensity of radiation 辐射强度的变化Strategic and tactical response of plants to radiation 植物对辐射的战略和战术响应Compensation point 补偿点Photosynthetically active radiation （PAR）光和活性辐射Efficiency of Photosynthesis 光合作用效率Photosynthetic capacity 光合能力Diurnal and annual rhythms of solar radiation 太阳辐射日节律和年节律Resource depletion zone 资源耗竭带Strategic difference 战略差异Tactical response 战术响应Transpiration 蒸腾Net assimilation 净同化量Nutrient sources 营养物资源Nutrient budgets 营养预算Terrestrial communities 陆地群落Aquatic communities 水生群落Geochemistry 地球化学Global biogeochemical cycles 全球生物地球循环Mechanical weathering 机械风化Chemical weathering 化学腐蚀Wetfall 湿降落Dryfall 干降落Rainout component 雨水冲失成分Washout component 水冲失成分Streamflow 溪流Denitrification 脱氮Endorheic内陆湖泊Biogeochemistry 生物地球化学Hydrosphere carbon 水圈的碳Weathering 风化作用Nitrogen cycle 氮循环Phosphorus 氮Sediment 沉积型Lithospheric 岩石圈Sulfur 硫The fate of matter in the community群落中物质的命运Producers 生产者Consumers 消费者Decomposers 分解者Autotrophs 自养生物Grazing mammals 草食哺乳动物Phytoplankton 浮游植物Zooplankton 浮游动物Bacteria 细菌Fungi 真菌Nonliving 无生命Food chains 食物链Primary and secondary production 初级和次级生产力Net Primary production 净初级生产力Aphotic zone 无光区Photic zone 透光区Primary consumers 初级消费者Secondary consumer 次级消费者Soil formation 土壤形成The soil profile 土壤剖面Primary classification：the great soil groups 主要分类：大土壤群Higher vegetation 高等植物Dynamic mixture 动态混合物Organic matter 有机质Cells 细胞Pedology 土壤学Subsoil 亚土壤Mineral soil 矿物质土壤Parent material 母质Soil series 土系Soil surveyor 土壤勘测员Succession 演替Ecosystem patterns 生态系统格局Soil horizons 土层Humic acids 腐植酸Great soil groups 土壤群Population size 种群大小Age and stage structure 年龄和时期结构Zygote 受精卵Unitary organism 单体生物Modular organism 构件生物Ramets 无性系分株Clone 无性系Genet 基株Evolutionary individuals 进化个体Immediate ecological impact 直接生态作用Stable age distribution 稳定年龄分布Age pyramid 年龄金字塔Stationary age distribution 固定的年龄分布Stage structure 时期结构Sizes classes 个体大小群Natality 出生率Mortality 死亡率Survivorship 存活率Life tables 生命表K-factor analysis k-因子分析The fecundity schedule 生殖力表Population growth 种群增长Density-independent Population growth 非密度制约性种群增长Density-dependent growth-the logistic equation 密度制约性种群增长：逻辑斯缔方程Life expectancy 生命期望Survivorship curve 存活曲线Cohort 同生群Age-specific survival rate 特定年龄存活率Key factors 关键因子Killing factor 致死因子Basic reproduction rate 基础繁殖率Carrying capacity 环境容纳量Estimating density 估计密度Mark release recapture 标记重捕法H3Density dependence密度制约Equilibrium population density 平衡种群密度Relative density相对密度Allee effect阿利效应Exactly compensating准确补偿Undercompensating补偿不足Overcompensating过度补偿H4Population fluctuations 种群波动Chaos 混沌Expanding and contracting populations 增长种群和收缩种群Stable limit cycle 稳定极限环I1Competition 竞争Predation 捕食Parasitism 寄生Mutualism互利共生Intraspecific competition种内竞争Interspecific competition种间竞争Exploitation competition利用性竞争Interference competition干扰性竞争Cannibalism 自相残杀Altruism 利他主义Commensualism 偏利共生Amensualism偏害共生I2Dispersal扩散Territoriality领域性Niche shift生态位转移Allelopathy异株克生Competive asymmetry 竞争不对称Scramble competition争夺竞争Contest competition格斗竞争Zero net growth isocline零增长等斜线Self-thinning自疏Inbreeding近亲繁殖Reproductive value繁殖价值Leks 求偶场I3Competitive exclusion 竞争排斥Limiting similarity 极限相似性Competitive release 极限释放Character displacement 性状替换Apparent competition 表观竞争Enemy-free space 无敌空间Highly heterogeneous 高度异质性Gaps 断层Probability refuge 隐蔽机率J1Herbivores 食草动物Carnivores 食肉动物Omnivores 杂食动物Chemical defences 化学防御Behavioral strategies 行为对策Specialists 特化种Generalist 泛化种Monophagous单食者Oligophagous寡食者Polyphagous 多食者Parasites 寄生者J2Predator switching 捕食者转换Profitability of prey 猎物收益率Plant defence 植物防御The ideal free distribution 理想自由分布Functional response 功能反应Superpredation 超捕食K1Parasites 寄生物Modes of transmission 传播方式Social parasites 社会性寄生物Helminth worms 寄生蠕虫Insects 昆虫Necrotrophs 食尸动物Parasitoids 拟寄生物The cellular immune response 细胞免疫反应Vectors 媒介Optimal habitat use 最佳生境利用Brood parasitism 窝寄生Evolutionary constraint 进化约束K2Immunity 免疫Cevolution协同进化Gene for gene 基因对基因Mimics 模仿Herd immunity 群体免疫Antigenic stability 抗原稳定L1Pollination 传粉Symbiotic 共生性Obligate 专性Lichens 地衣Outcrossing 异型杂交Mitochondria 线粒体Chloroplasts 叶绿体M1Reproductive values 生殖价Hypothetical organism 假定生物Migration 迁移Senescence衰老Diapause 滞育Dormancy 休眠Longevity 寿命Enormous variation 巨大变异Energy allocation 能量分配Semelparity 单次生殖Iteroparity 多次生殖Carrying capacity 容纳量Current/future reproduction当前/未来繁殖Habitat disturbance 环境干扰The current/future reproductive output 当前/未来繁殖输出A high/low cost of reproduction 高/低繁殖付出Seed bank 种子库Torper蛰伏Hibernation 冬眠Cryptobiosis 隐生现象Aestivation 夏眠Migration 迁徙Morphological forms 形态学性状Generations世代Mechanistic level 机制水平N1Cooperation 合作Grouping-benefits 集群-好处Altruism 利他行为Group defens e 群防御Inclusive fitness 广义适合度Eusociality 真社会性Hymenoptera 膜翅目Haplodiploid 单倍二倍体Venomous sting毒刺N2Sex 性The costs of inbreeding 近交的代价Self-fertilization 自体受精Sexual versus asexual reproduction 有性和无性生殖Sex ratio 交配体制Monogyny 单配制Polygyny 一雄多雌制Polyandry 一雌多雄制Inbreeding depression 近交衰退Hermaphrodite 雌雄同体Recombine 重组Rare type advantage 稀少型有利Equal investment 相等投入Local mate competition局域交配竞争Epigamic 诱惑性Intrasexual selection 性内选择Intersexual selection 性间选择O1Alleles 等位基因Polymorphism 多型Genetic drift 遗传漂变Genetic bottleneck 遗传瓶颈Rare species 稀有物种Extinction 灭绝Chromosome染色体Genotype 遗传型Phenotype 表现型Gene pool 基因库Gel electrophoresis 凝胶电泳O2Gene flow 基因流Differentiation 分化Sibling species 姊妹种Genetic revolution 遗传演变Peripheral isolates 边缘隔离PTransfer efficiencies 转换效率（net）primary productivity (净)初级生产力Respiratory heat 呼吸热Grazer system 牧食者系统Food chains 食物链Pathways of nutrient flow营养物流Food webs 食物网QCommunity structure 群落结构Community boundaries 群落边界Guilds同资源种团Community organization 群落组织Species diversity 物种多样性Energy flow 能量流Superorganism 超有机体Species-poor/rich 物种贫乏/丰富Biomass stability 生物量稳定性Tundra 冻原Island biogeography 岛屿生物地理学Turnover rate 周转率Source of colonists 移植者源Relaxation松弛Edgespecies 边缘物种Interior species 内部物种Corridor 走廊Greenways 绿色通道Community assembly群落集合Grazers 食草动物Carnivores 食肉动物Keystone species 关键物种Dominance control 优势控制Habitat affinity生境亲和力Prey switching 猎物转换RSuccession 演替Climax Community 顶级群落Pioneer species 先锋物种Primary succession 原生演替Alluvial deposit 冲积层Secondary succession 次生演替Acidifying effect 酸化作用Opportunistic机会主义Cellulose 植物纤维素Lignin 木质素Resource ratio hypothesis 资源比假说Fluctuations 波动Cyclic succession 循环演替Disturbance 干扰Patch dynamics板块动态Mini-succession 微型演替Cambium 形成层Neotropical forest 新热带雨林Priority effect 优先效应SVegetation 植被Ecotones 群落交错区Climate map 气候图Biomes 生物群系Heat budget 热量预算Zonation 分带Grassland 草地Primary regions 基本区域Desertification 荒漠化Arctic tundra 北极冻原Alpine tundra 高山冻原Permafrost 永冻层Coniferous boreal forest北方针叶林Temperature forest 温带森林Tropical forest 热带森林Salinization 盐渍化Primary saltwater regions 基本盐水区域Opens oceans 开阔海洋Continental shelves 大陆架The intertidal zone 潮间带Salt marsh 盐沼Mudflats淤泥滩Mangroves 红树林Pelagic 浮游生物Photic zone 有光带Phyto plankton 浮游植物Nekton 自泳动物Benthic 底栖Rocky shore 岩岸Zonation 分带Streams 溪流Ponds 池塘Environmental concerns 环境关系Catchment area 集水区Temperature inversion 温度逆转Biomanipulation 生物处理TThe goals of harvesting 收获目标Quota limitation 配额限制Environmental fluctuation环境波动Maximum possible yiel最大可能产量Net recruitment 净补充量Surplus yield 过剩产量Age structure 年龄结构Population data 种群数据Stable equilibrium 稳定平衡Harvesting effort 收获努力Gun licences 猎枪执照Rod licences钓鱼许可证Upwelling of cold water冷水上升流Fisheries 渔业Ocean productivity 大洋生产力The tragedy of the common公共灾难Overexploitation 过捕Pollution 污染Global decline 全球性下降By-catch 附带收获Community perturbations 群落扰动Oil spills 原油泄漏Eutrophication 富营养化Algal blooms 水华Red tides 赤潮Biomagnification 生物放大作用UPest 有害生物Natural enemies 天敌Ruderal 杂草型Economic/aesthetic injury level 经济/美学损害水平Cultural 栽培Biological control 生物防治‘Silent spring’寂静的春天Chemical toxicity 化学毒性Evolution of resistance抗性进化Microbial insecticide微生物杀虫剂Inoculation接种Augmentation扩大Inundation 爆发VRare species 稀有种Genetic diversity 遗传多样性Extinction 灭绝Endemic species 特有种Habitat fragmentation 生境片段化Insularization 岛屿化Biodiversity 生物多样性Strategies for conservation保育对策Antarctic treaty 南极协议Ecotourism生态旅游WAir pollution空气污染Acid rain 酸雨Water pollutants 水体污染物Soil pollution 土壤污染Acid deposition 酸降Pathogens病源体Chemical oxygen demand 化学需氧量Anaerobes 厌氧菌The greenhouse effect 温室效应Carbon dioxide 二氧化碳Ozone 臭氧Photochemical smog 光化学烟雾XOverview 概述Soil erosion 土壤侵蚀Soil compaction 土壤硬结Contour ploughing等高耕作Cover crops 覆盖作物No-till farming 免耕农业。
National_Economy_Continues_Stable_Recovery
National Economy Continues Stable RecoveryI n April, production and demand continued to grow, employment and prices were generally stable, and new growth drivers were cultivated and thriving. The national economy continued the momentum of stable recovery.1. Industrial production maintained stable growth, and equipment manufacturing and high-tech manufacturing grew fastIn April, the total value added of industrial enterprises above the desig-nated size grew by 9.8% year on year, a two-year average growth of 6.8%, or 0.6% age points faster than that of March; month-on-month growth was 0.52%. I n terms of sectors, thevalue added of mining grew by 3.2% year on year, with a two-year average growth of 1.7%; manufacturing up by 10.3% year on year with two-year average growth of 7.6%; the produc-tion and supply of electricity, heat power, gas and water up by 10.3% year on year with the two-year aver-age growth up by 5.1%. Equipment manufacturing and high-tech manu-facturing value added grew by 13.1% and 12.7% year on year, or two-year average growths of 11.2% and 11.6% respectively. I n terms of the output of products, year-on-year growth of new energy vehicles, industrial ro-bots, integrated circuits and micro computer equipment reached 175.9%, 43.0%, 29.4% and 13.5% respectively with two-year average growths all exceeding 19%. An analysis by types of ownership showed that, the value added of the state holding enterprises grew by 8.6% year on year; that of share-holding enterprises went up by 10.4%; that of enterprises funded by foreign investors or investors from Hong Kong, Macao and Taiwan went up by 8.4%; and that of private enter-prises went up by 11.2%. I n the first four months, industrial enterprises above the designated size’s total value added of went up by 20.3% year on year with a two-year average growth of 7%. I n April, the Manufacturing Purchasing Managers’ I ndex stood at 51.1%, staying above the threshold for fourteen consecutive months. The Production and Operation Expecta-tion Index registered 58.3%.By Lily Wang22I n the first three months, total profits made by industrial enterprises above the designated size reached RMB 1,825.4 billion, an increase of 1.37 times compared with that of the same period last year, with a two-year average growth of 22.6%. The profit rate of the business revenue of indus-trial enterprises above the designated size was 6.64%, 2.76% age points higher than that of the first three months in 2020.2. The service sector maintained growth and the business activity index for services stayed within the expansion rangeI n April, the I ndex of Services Production increased by 18.2% year on year, with a t wo-year average growth of 6.2%. I n terms of major sectors, the Production I ndices for eight sectors all maintained a year-on-year growth. In the first four months, the I ndex of Services Production grew by 26.4% year on year, with a two-year average growth of 6.7%. In the first three months, business reve-nue for services enterprises above the designated size grew by 37.1% with a two-year average growth reaching 10.2%. Of this total, the business revenue of information transmission, software and information technology services and that of scientific research and technolog y ser vices grew by 31.7% and 43.5% year on year, with the two-year average growths reach-ing 17.0% and 11.7% respectively. I n April, the Business Activity I ndex for services was 54.4%, staying above the threshold for fourteen consecu-tive months. I n terms of sectors, the Business Activity I ndex for railway transportation, air transportation and accommodation stayed above 65%. Meanwhile, some industries hit hard by the COVID-19 pandemic acceler-ated recovery evidently with the Busi-ness Activities I ndex for accommo-dation, catering, ecological protection and environmental treatment, culture, sports and recreation registering 1.8% age points to 5.7% age points high-er than that of the previous month. I n terms of market expectation, the Business Activity Expectation I ndex for ser vices stood at 62.7%, stay-ing within high expansion range of 60% and above for three consecutive months.3. Market sales continued recovering and the online retail sales grew fast I n April, the total retail sales of consumer goods reached RMB 3,315.3 billion, up by 17.7% year on year, an two-year average growth of 4.3%; and the month-on-month growth was 0.32%. Analyzed by dif-ferent areas, the retail sales in urban areas reached RMB 2,888.8 billion, up by 17.6% year on year, a two-year average growth of 4.3%; the retail sales in rural areas reached RMB 426.5 billion, up by 17.8%, a two-year average growth of 4.3%. Grouped by consumption, the retail sales of goods was RMB 2,977.6 billion, up by 15.1% year on year, a two-year av-erage growth of 4.8%; the income of catering was RMB 337.7 billion, up by 46.4%, a two-year average growth of 0.4%. Grouped by categories, for retail sales of goods by enterprises above the designated size in April, the year-on-year growth rate of 13 categories exceeded 10%. I n terms of the t wo-year average grow th, the retail sales of all categories kept positive growth except that of the household electric appliances. Of the total, the two-year average growth of 10 categories including sports and recreational articles, gold, silver and jewellery, and telecommunication equipment exceeded 10%. The online retail sales continued to grow. In the first four months, the online retail sales reached RMB 3,763.8 billion, a year-on-year growth of 27.6%, a two-year average growth of 13.9%. Specifically, the online retail sales of physical goods was RMB 3,077.4 bil-lion, a year-on-year growth of 23.1%, a two-year average growth of 15.6%, accounting for 22.2% of the total re-tail sales of consumer goods.4. Investment in fixed assets continued to recover and investment in the primary industry, high-tech industries and social sectors grew fast I n the f irst four months, theinvestment in fixed assets (exclud-In April, theIndex of ServicesProductionincreased by18.2% year onyear, with theaverage two-yeargrowth of 6.2%.23ing rural households) reached RMB 14,380.4 billion, up by 19.9% year on year, with a two-year average growth of 3.9%. I n April, the investment in fixed assets grew by 1.49% month on month. Specifically, in the first four months, the investment in infrastruc-ture grew by 18.4% year on year, an average two-year increase of 2.4%; the investment in manufacturing grew by 23.8% year on year, an average two-year decrease of 0.4%; the investment in real estate development grew by 21.6% year on year, a two-year aver-age growth of 8.4%. The floor space of commercial buildings sold reached 503.05 million square meters, up by 48.1% year on year with the two-year average growth of 9.3%; and the total sales of commercial buildings were RMB 5,360.9 billion, up by 68.2% year on year with the two-year aver-age growth of 17.0%. By industry, the investment in the primary industry went up by 35.5% year on year, a two-year average growth of 15.2%; the secondary industry up by 21.7% year on year, an average two-year increase of 0.8%; the tertiar y industr y up by 18.7% year on year, a two-year average growth of 5%. The private investment went up by 21% year on year, a two-year average growth of 2.9%. The investment in high-tech indust r y g rew by 28.8% yea r on year, a two-year average growth of 11.8%. Specifically, the investment in high-tech manufacturing and high-tech services grew by 34.2% and 18.1% year on year w ith the two-year average growths of 13.7% and 7.8%. I n terms of high-tech manufacturing, the investment in manufacturing of medical equip-ment, measuring instrument and equipment and in manufacturing of medicine grew by 40.3% and 33.1% year on year with the two-year av-erage growths of 13.4% and 13.8%.I n terms of high-tech services, the investment in testing services and e-commerce ser vices went up by 46.1% and 39.1% year on year with the t wo-year average growths of 17.6% and 32.2%. The investment in social sectors grew by 26.3% year on year with the two-year average growth of 10.6%. Specifically, the investment in health sector and ed-ucation sector grew by 46.5% and22.1% year on year with the two-year average growths of 23.9% and12.1%.5. Imports and exports ofgoods witnessed a strongmomentum of growth and thetrade structure continued tobe optimizedI n April, the total value of im-ports and exports of goods was RMB3,149.2 billion, up by 26.6% year onyear. The value of exports was RMB1,712.8 billion, up by 22.2% year onyear, and the value of imports wasRMB 1,436.3 billion, up by 32.2%year on year. The trade balance wasR MB 276.5 billion in surplus. I nthe first four months, the total valueof imports and exports of goods wasRMB 11,623.7 billion, up by 28.5%year on year. The value of exports wasRMB 6,325.5 billion, up by 33.8%year on year, and the value of importswas R MB 5,298.2 bil lion, up by22.7% year on year. The trade struc-ture continued to optimize. I n thefirst four months, the exports of me-chanical and electrical products grewby 36.3% year on year, accounting for59.9% of the total exports. The importand export of general trade account-ed for 61.6% of the total value of theimports and exports, 1.8% age pointshigher than the same period of theprevious year. The imports and ex-ports by private enterprises accountedfor 47.2% of the total imports andexports, 4.1% age points higher thanthe same period of the previous year.6. Consumer prices weregenerally stable and producerprices for industrial productswent up year on yearI n April, consumer prices wentup by 0.9% year on year, 0.5% fast-er than March, and down by 0.3%month on month. Grouped by com-modity categories, prices for food,tobacco and alcohol went up by 0.1%year on year; clothing up by 0.2%;housing up by 0.4%; articles and ser-vices for daily use up by 0.4%; trans-port and communication up by 4.9%;education, culture and recreation upby 1.3%; medical services and healthcare up by 0.1%; and other articlesand services down by 1.3%. Amongthe prices for food, tobacco and alco-hol, the price for pork went down by21.4%, fresh vegetables down by 1.3%,grain up by 1.1% and fresh fruit upby 2.7%. The core CPI excluding theprice of food and energy went up by0.7%, 0.4% faster than March. In thefirst four months, the consumer pricewent up by 0.2% year on year. 24。
无导线起搏器临床应用的初步探讨及随访结果分析
DOI：10.3969/j.issn.1007-5062.2020.12.006•临床论著•无导线起搏器临床应用的初步探讨及随访结果分析梁静史冬梅赵迎新周玉杰李月平柴萌韩红亚杨丽霞许晓啥［摘要］目的：分析Micra TM无导线起搏器在临床患者中应用的有效性及安全性。
方法：2018年8月至2018年12月，于北京安贞医院置入Micra TM无导线起搏器的患者，随访1年。
记录手术时间，X线透视时间,释放次数，术中，岀院前及术后1、3、6、12个月的起搏器程控参数(阈值、感知、阻抗)和并发症及严重不良事件。
结果：共入选患者15例，平均年龄(68.53士11.93)岁，男性8例(53.3),均成功置入Micra™无导线起搏器,平均手术时间(36.50±2,37)min,平均X线透视时间(9.42±6,13)min,平均Micra释放次数(1.53±0.74)次。
术中，岀院前及术后1,3,6,12个月起搏器程控参数：阈值<1.0V@0.24ms,感知逐渐升高，阻抗逐渐降低，参数理想且稳定。
其中6例患者术后6-8周行心脏核磁共振平扫检查，检查后1个月阈值、感知、阻抗参数稳定,无明显变化。
所有患者无穿刺部位血肿、岀血、动静脉痿、假性动脉瘤、心脏穿孔、心包积液、置入器械移位和感染等不良事件发生。
结论：无导线起搏器置入操作成功率高,手术时间短,起搏器电学参数理想且稳定,核磁共振检查不影响起搏参数,临床患者中应用安全有效。
［关键词］心律失常;心动过缓;无导线起搏器;起搏器置入术［中图分类号］R54［文献标志码］A［文章编号］1007-5062(2020)12-1440-05An initial implantation experience of leadless pacemaker using the Micra™transcatheter pacing systemUXNG仇"g,SHI Do"g陀,，ZHXO!7"g血"，ZHO〃Yujie,LI Yuepi"g,CHAI Me"g,HXN Ho"gya,YANG厶，如a,XiaoAa"Departrne"t of Cardiology,Bei/i"g A"^Ae"Hospital,Capital MedicaZ/"iversity,BeijingInstitute of Heart,Lu."g a"d Blood Vessel Diseases,Beijing Aey Laboratory of Precisio"Medicine of Coro"aryAtherosclerotic Disease,Cli"ical Ce"ter foT Coro"ary Heart Disease,Capital Medical/"iversity,Beijing100029,China［Abstract］Objective:To describe the efficacy and safety of leadless pacemaker using the Micra™transcatheter pacing system.Methods:Patients underwent Micra™transcatheter pacing system implementationin Beijing Anzhen hospital from August2018to December2018were enrolled and followed12months.The procedure duration，average fluoroscopy time and number of deployment were recorded.The pacing parameters(threshold，R-Wave amplitude，impedance)，implementation related complications，and adverse events at implant,hospital discharge,1,3,6,12months post-implant were studied.Results:Totally fifteen subjects wereenrolled with successful pacemaker implantation.The average age was(68.5±11.9)years and8patients(53.3)were males.The mean procedure time was(36.50±2.37)minutes.The average fluoroscopy time was(9.42士6.13)minutes and the number of deployment was(1.53±0.74).The capture thresholds at implantation,hospital discharge and1,3,6,12months post-implant were low and stable(<1.0V@0.24ms).R-Wave amplitudeand impedance were excellent through12months.6patients underwent cardiac magnetic resonance imaging基金项目：国家重点研发计划“精准医学研究”重点专项(2017YFC0908800)；北京市医院管理局“使命”计划专项经费(SML20180601)；北京市卫生健康委员会科技创新中心建设项目(PXM2019_026272_000006,PXM2019_026272_000005)作者单位：100029首都医科大学附属北京安贞医院-北京市心肺血管疾病研究所冠心病精准治疗北京市重点实验室首都医科大学冠心病临床诊疗与研究中心心内十二病房通信作者:周玉杰，医学博士，主任医师，教授，博士生导师，主要从事心血管介入治疗。
科技英语词汇
conductivities 电导率elemental semiconductor 元素半导体periodic table 元素周期表compound semiconductor 化合物半导体combinations 化合Amorphous 非晶polycrystalline多晶single crystal 单晶ordered region 有序化区域grains 晶粒grain boundaries 晶界periodic table 周期表inert elements 惰性元素valence electrons 价带电子positively charged 带正电ionic bond 离子键Atomic bonding 原子价键)colsed-valence energy shells 满价带能量壳层covalent bond 共价键lowest energy shell 最低能量壳层valence shell 价电子层thermal vibration 热振动thermal energy 热能lattice vibrations 晶格振动point defect 点缺陷lattice point 晶格点vacancy 空位interstitial 间隙line defect 线缺陷line dislocation 线位错interstitial impurities 间隙杂质substitutional impurities 替位杂质doping 掺杂Doping diffusion 杂质扩散ion implantation 离子注入Growth from melt 熔体法生长Czochralski method 丘克拉斯基法，提拉法seed 籽晶solidification 结晶solid-liquid interface 固液界面.Epitaxial Growth 外延生长single-crystal substrate 单晶衬底homoepitaxy 同质外延heteroepitaxy 异质外延ternary alloy 三元合金Principle of Quantum Mechanics 量子力学Energy Quanta 能量子monochromatic light 单色光photoelectric effect 光电效应incident intensity 入射光强度kinetic energy 动能limiting frequency 截止频率photon 光子work function 功函数Wave-Particle Duality Principle 波粒二象性matter waves 物质波particle-like behavior 粒子性wave-like properties 波动性electromagnetic waves 电磁波classical laws of physics 经典力学wave mechanics 波动力学wave theory 波动理论Schrödinger’s wave equation 薛定谔波动方程The one-electron atom 单电子原子，氢potential 势能principal quantum number 主量子数mass of the electron 电子质量bound 束缚nucleus 原子核quantized 量子化quantum numbers 量子数quantum state 量子态Pauli exclusion principle 泡利不相容原理discrete energy levels 分立能级energy level 能级outermost electrons 最外层电子band of allowed energies 允带band of forbidden energies 禁带allowed and forbidden bands 允带和禁带valence electrons 价带电子absolute zero 绝对零度)bandgap energy 带隙能量valence band 价带conduction band 导带forbidden energy band 禁带Carrier generation 载流子产生Carrier recombination 载流子复合Carrier transport 载流子输运intrinsic carrier concentration 本征载流子浓度free carriers 自由载流子intrinsic semiconductor 本征半导体Doping 掺杂majority carrier 多数载流子minority carrier 少数载流子electron hole pair 电子空穴对meta-stable state 亚稳态Radiative recombination 辐射复合Auger recombination 俄歇复合Light-emitting diodes发光二极管defects缺陷forbidden region 禁带区域heavily doped 重掺杂heavily excited重激发net movement 净流动net carrier flow 净载流子流动thermal velocity 热运动速度electric field 电场constant velocity 恒定速度acceleration 加速度Transport 输运drift transport漂移运动solar cells太阳能电池photodiodes 光电二极管bipolar junction transistors (BJTs) 双极晶体管depletion region耗尽区majority carrier 多子minority carrier 少子diffusion current 扩散电流drift current 漂移电流net current 净电流Forward Bias正向偏压Reverse Bias 反向偏压net electric field 净电场built-in field 内建电场minority carrier injection 少数载流子注入external circuit 外电路n-channel n沟four-terminal 四端MOS capacitor MOS电容gate 栅source 源drain 漏channel region 沟道区positive gate voltage 正栅压vertical electric field 垂直电场inversion layer 反型层channel region 沟道区drain-to-source voltage 漏源电压channel 沟道field-effect场效应transistor action晶体管效应n-channel MOSFET n沟MOSFET threshold voltage 阈值电压inversion layer 反型层drain current 漏电流gate voltages 栅压capacitor 电容器polycrystalline silicon 多晶硅parallel-plate capacitor 平行板电容器semiconductor substrate 半导体衬底) metal gate 金属栅accumulation layer of hole 空穴堆积层inversion layer of electrons 电子反型层NMOS devices NMOS器件n-channel enhancement mode MOSFET n沟道增强型MOSFETpositive gate voltage 正栅压electron inversion layer 电子反型层n-channel depletion mode MOSFET n沟道耗尽型MOSFET threshold voltage 阈值电压p-channel enhancement-mode MOSFET p沟增强型MOSFETp-channel depletion mode MOSFET p沟耗尽型MOSFET negative gate voltage 负栅压inversion layer of holes 空穴反型层channel stop 沟道截断active device region 有源器件区photoresist 光刻胶silicon dioxide 二氧化硅silicon nitride 氮化硅gate oxide 栅氧化物threshold voltage 阈值电压ion implantation 离子注入polysilicon layer 多晶硅层photolithography 光刻metallization 镀金属.complementary metal-oxide-semiconductor (CMOS) inverter 互补型金属氧化物半导体反相器p-well process p阱工艺p-channel MOSFET p沟MOSFETp well p阱potential 电势reverse biased 反向偏压的The integrated circuit IC, 集成电路interconnect lines 互连线chip 芯片gate insulator 栅绝缘层native oxide 天然氧化物diffusion coefficient 扩散系数quartz tube 石英管Impurity doping 杂质掺杂Diffusion 扩散ion implantation 离子注入epitaxial growth 外延生长infinite source 无限源limited source 有限源predeposition 预淀积drive-in diffusion 主扩散implant ions 注入离子photoresist 光刻胶oxides 氧化物Photomasks 光掩膜版Photolithography 光刻plasma 等离子体Plasma etching 等离子刻蚀cathode 阴极anode 阳极Metallization 镀电极Bonding 键合Packaging 封装vapor deposition technique 气相沉积技术。
氨水物性
28
APPENDIX A - THE IAPWS FORMULATION FOR THE THERMAL CONDUCTIVITY OF ORDINARY WATER SUBSTANCE
FOR INDUSTRIAL USE
29
APPENDIX B - THE IAPWS FORMULATION FOR THE DYNAMIC VISCOSITY OF ORDINARY WATER SUBSTANCE FOR
Unit
K bar
kJ.kg-1 kJ.kg-1.K-1 m2.s-1 kg.m-3 mW.m-1.K-1 :Pa.s mN.m-1 -
2 / 34 Properties of Working Fluids - NH3 H2O
M. CONDE ENGINEERING — 2004
2.
INTRODUCTION
22
13.
DYNAMIC VISCOSITY OF SOLUTIONS IN THE VAPOUR PHASE
25
14.
DENSITY OF SATURATED SOLUTIONS IN THE VAPOUR PHASE
26
15.
SPECIFIC THERMAL CAPACITY OF SATURATED SOLUTIONS IN THE VAPOUR PHASE
8
6.
SPECIFIC THERMAL CAPACITY OF SATURATED LIQUID SOLUTIONS AT CONSTANT PRESSURE
9
7.
THERMAL CONDUCTIVITY OF LIQUID SOLUTIONS
11
8.
RaPET
RaPET® RFSECTION 1 – PRODUCT AND COMPANY IDENTIFICATIONProduct Identification: RaPET® RFRef No. 1155, 1155-050, etc.Test kit contains RF Latex Reagent, RF Positive Control, Negative Control, and Glycine-Saline Buffer (20X) Concentrate.Company Identification: Stanbio LaboratoryMainStreetNorth126178006Boerne,TXTelephone Number: (830) 249-0772Website: SECTION 2 – HAZARDS IDENTIFICATIONRoutes of Exposure: Only when used as directed.Classification system: In compliance with OSHA’s Hazard Communication Standard (29CFR 1910.1200), a chemical mixture is considered hazardous if it contains 1.0% or more of a hazardous compound or 0.1% or more of a carcinogen. The product contains hazardous material(s) in excess of these amounts; therefore, precautions adequate for the pure form of the material(s) are presented here.National Fire Protection Association (NFPA) ratings (scale 0-4):Health=0Fire=0Reactivity=0Hazard OverviewHealth: Minimal risk if used as directed.Fire: Not considered a fire hazard.Reactivity: Glycine-Saline Buffer (20X) Concentrate contains Sodium Chloride; Glycine; and Sodium Azide. Minimal risk.Special Hazards:Sodium Chloride: Not considered a fire hazard.Glycine: With heat, oxides of nitrogen, ammonia, carbon monoxide and carbon dioxide are formed. Sodium Azide: In dry form, decomposes explosively on heating. Reacts with copper and lead to produce explosive azides.Carcinogenicity informationOSHA (Occupational Safety and Health Administration): None of the ingredients is listed. NTP (National Toxicology Program): None of the ingredients is listed.IARC (International Agency for Research on Cancer): None of the ingredients is listed. SECTION 3 – PRODUCT COMPOSITIONThe test kit is composed of RF Latex Reagent, RF Positive Control, Negative Control, and Glycine-Saline Buffer (20X) Concentrate.RF Latex Reagent/1156 (The reagent contains by percentage the following amounts of chemicals)RaPET® RFName CASNo. Concentration ChemicalNone determined to be hazardous.RF Positive Control/1157 (The reagent contains by percentage the following amounts of chemicals)No. Concentration ChemicalName CASNone determined to be hazardous.Negative Control/1192 (The reagent contains by percentage the following amounts of chemicals)No. Concentration Name CASChemicalNone determined to be hazardous.Glycine-Saline Buffer (20X) Concentrate/1191 (The reagent contains by percentage the following amounts of chemicals)No. Concentration ChemicalName CAS**% Chloride 7647-14-5 20.0 Sodium**% Glycine 56-40-6 15.0%**2.0AzideSodium26628-22-8**Once concentrate is diluted to final volume, solution is below hazardous limits: sodium chloride will be 1%, glycine will be 0.75%, sodium azide will be 0.1%.SECTION 4 – FIRST AID MEASURESRESPIRATORY PROTECTION: None required unless product is mistedventilationVENTILATION: GoodGLOVES: YesLAB COAT: YesPROTECTION:YesEYELABORATORY PRECAUTIONS: Normal laboratory precautions are recommended.SECTION 5 – FIRE FIGHTING MEASURESSodium ChlorideHAZARDS: Not considered a fire hazard.EXTINGUISHING MEDIA: For small fires, use water spray, dry chemical, carbondioxide or chemical foam for surrounding fire. Material is not considered fire hazard.GENERAL INFORMATION: Wear a self-contained breathing apparatus and protectiveclothing.GlycineHAZARDS: With heat, oxides of nitrogen, ammonia, carbon monoxide and carbondioxide are formed.EXTINGUISHING MEDIA: For small fires, use water spray, dry chemical, carbondioxide or chemical foam for surrounding fire. Material is not considered fire hazard.RaPET® RFGENERAL INFORMATION: Wear a self-contained breathing apparatus and protectiveclothing.Sodium AzideHAZARDS: In dry form, decomposes explosively on heating. Reacts with copper andlead to produce explosive azides. In wet form, as presented in reagent, the product issignificantly less reactive, however, careful handling should be used when pouring reagentdown sink. Adequate flushing of water down drain should be done to avoid accumulation.EXTINGUISHING MEDIA: Dry chemical, foam or carbon dioxide.GENERAL INFORMATION: Wear a self-contained breathing apparatus and protectiveclothing.SECTION 6 – ACCIDENTAL RELEASE MEASURESSafe work practices: Disposal should be made in accordance with existing disposal practices employed for infectious waste.Measures for environmental protection:Prevent liquid and vapor from entering sewage system, storm drains, surface waters, and soil.Measures for cleaning/ collecting: Wash spill area with appropriate cleaning materials. Dispose of in a manner consistent with federal, state and local regulation.SECTION 7 – HANDLING AND STORAGEInformation for safe handling: Refer to the package insert or product label for additional information on storage conditions.Information about protection against explosions and fires: No special measures required. Requirements to be met by storerooms and receptacles: Refer to the package insert or product label for additional information on storage conditions.Information about storage in one common storage facility:Store product in original packaging.Further information about storage conditions:Protect from heat and direct sunlight.SECTION 8 – EXPOSURE CONTROLS/PERSONAL PROTECTION Components with Occupational Exposure Limits: The product does not contain any hazardous ingredients with occupational exposure limits established by OSHA, ACGIH, or NIOSH. General protective and hygienic measures: Always maintain good housekeeping. Do not eat, drink or store food and beverages in areas where chemicals are used. Wash hands before breaks and at the end of the work shift.Breathing equipment: Use adequate protection to prevent inhalation, as well as good ventilation. Hand protection:Wear necessary gloves when handling.Eye protection:Wear appropriate safety glasses or other protective eyewear.Body protection:Wear apron, laboratory coat or appropriate protective clothing when handling. General notes: Control is a potential biohazardous material. Source materials from which this product was produced were found negative for HBsAG and for antibodies against HCV and HIV by approved test methods. No test can offer complete assurance that infectious agents are absent, this product should be handled observing the same safety precautions employed when handling any potentially infectious material.RaPET® RFSECTION 9 – PHYSICAL AND CHEMICAL PROPERTIES Sodium ChlorideBoiling Point: 1413°CMelting Point: 801°CSpecific Gravity: 2.16Flash Point: NAGlycineBoiling Point: NAMelting Point: 290°CSpecific Gravity: 1.16Flash Point: NASodium AzideBoiling Point: NAMelting Point: 300°CSpecific Gravity: 1.85Flash Point: Not identifiedSECTION 10 – STABILITY AND REACTIVITYGlycine-Saline Buffer contains sodium chloride, glycine and sodium azide.StableSTABILITY:NoneINCOMPATIBILITY:HAZARDOUS POLYMERIZATION: Will not occurSECTION 11 – TOXICOLOGICAL INFORMATIONSodium ChlorideTHRESHOLD LIMIT: Not establishedLD50 (oral rat): 3000 mg/kgNoCARCINOGEN:GlycineTHRESHOLD LIMIT: Not establishedLD50 (oral rat): Not establishedNoCARCINOGEN:Sodium AzideTHRESHOLD LIMIT: Not establishedLD50 (oral rat): 27 mg/kgNoCARCINOGEN:SECTION 12 – ECOLOGICAL INFORMATIONToxicity: Further details: no data availablePersistence and degradability: Further details: no data available Bioaccumulative potential: Partition coefficient: n-octanol/water: no data available Mobility in soil: no data availableResults of PBT and vPvB assessment: no data availableRaPET® RFGeneral information: Do not allow to enter into ground-water, surface water or drains.SECTION 13 – DISPOSAL CONSIDERATIONSDispose of in a manner consistent with federal, state, and local regulations.SECTION 14 – TRANSPORT INFORMATIONDOT Class - Not restricted for transportation.IMDG Class - Marine pollutant: No, not restricted for transportation.ICAO/IATA Class - Not restricted for transportation.SECTION 15 – REGULATORY INFORMATIONSARA (Superfund Amendments and Reauthorization Act of 1986 – USA):Section 302/304 (40CFR355.40): The product does not contain listed substances.Section 313 (40CFR372.65): The product does not contain listed substances.California Proposition 65 (USA)Chemicals known to cause cancer: The product does not contain listed substances. Chemicals known to cause female reproductive toxicity: None of the ingredients is listed. Chemicals known to cause male reproductive toxicity: None of the ingredients is listed. Chemicals known to cause developmental reproductive toxicity: None of the ingredients is listed.Markings according to European guidelines: observe the general safety regulations when handling chemicals. The product does not require any hazard warnings according the respective European Community (EC) Directives.SECTION 16 – OTHER INFORMATIONThe information contained in this SDS is believed to be accurate and represents the best information currently available. Stanbio Laboratory makes no warranty, express or implied, with respect to such information, and we assume no liability resulting from its use. Users should determine suitability of the information contained in SDS for their particular purpose.In no way shall Stanbio Laboratory be liable for any claims, losses or damages resulting from using information contained in SDS.。
fanyi
6、Tensile strength and abutment relaxation as failure control mechanisms in underground excavationsAbstract：Classical assessment of instability potential in underground excavations are normally based on yield and rupture criteria for stress driven failure and on limit equilibrium analysis of structurally controlled failure. While it is true that ultimate failure and falls of ground can be an eventual consequence of stress fracturing and unfavourable structure within the rock mass, the timing of such failure is often controlled by the presence of residual tensile capacity, in the form of rock bridges separating joint segments and fractures and by the mechanisms of clamping and relaxation. Using crack and rock-bridge analogues in conjunction with an updated voussoir beam model, this paper explores the in¯uence of residual tensile strength and boundary parallel relaxation on the failure process. The impact on support design is also examined. In underground hard rock mines with complex geometries and interacting openings, relaxation is identi®ed as a key controlling factor in groundfall occurrence. Empirical stability assessment techniques for underground tunnels and for mining stopes are updated to account for relaxation.IntroductionStability assessment of underground excavations is classically divided into two procedural domains. These two domains are based on a distinction between struc-turally controlled and stress driven modes of instabil-ity. It is the premise of this paper, however, that in non-squeezing and non-bursting ground, structure and stress serve merely as ground conditioning mechan-isms. Gravity loading is ultimately responsible for large scale groundfalls or for signi®cant loading of support. When the rock mass jointing is non-persist-ent, the rock bridges contribute to the stability of an excavation through the rock mass residual tensile strength or load bearing capacity. The failure to con-sider the rock mass self-supporting capacity and the e.ects of abutment con®nement or abutment relax-ation can lead to erroneous predictions of failure or ofsupport load.Gravity induced groundfalls are common occur-rences in underground excavations of all depths. Numerous techniques can be applied to assess the po-tential for such groundfalls provided that an appropri-ate failure mode is assumed. Typical failure modes which can be analyzed include wedge fallout, slab or plug failure, gravity driven caving and beam failure.Models taking these failure modes into account are generally usually utilized for associated with stability assessments in low stress or near surface excavations. The underlying assumption of most of these models is that through-going joints or discontinuities are fully persistent and that stability is controlled by structural geometry and by friction (with or without dilation). The inherent tensile or cohesive strength of moderately jointed rock masses is often assumed to be negligible in these models.Alternatively, for excavations at depth or for shal-lower excavations in weaker rockmasses, linear elastic stress analysis can be used to determine the location and extent of problematic stress concentrations around the openings. Failure criteria such as Mohr±Coulomb and Hoek±Brown [1, 2] based on combined cohesive and frictional strength components can be applied suc- cessfully if the rock mass yields with signi®cant plastic deformation. These criteria, however, meet with only limited success [3, 4] for failure prediction around exca-vations in hard rock environments due to their insensi-tivity to low con®nement behaviour. In brittle ground, it has been shown [5±9] that under low con®nement (such as that which exists adjacent to an opening), tan-gential compressive stress above a de®ned threshold in-itiates and propagates boundary parallel cracks or fractures.Such rock mass damage can be responsible for observed seismicity [9] and stress redistribution [10] and was found to correlate well with a constant critical deviator criteria for damage initiation, both in intact and in moderately jointed rock [9, 11]. This initial cracking or fracturing is generally parallel to the exca-vation surface and therefore parallel to the major com-pressive stress. This crack damage is strain dependant and may be exacerbated by preferential de¯ection and dilation into an opening and by existing planes of weakness such as foliation or meta-bedding resulting eventually in moderately persistent planar laminations in otherwise massive or moderately jointed rock(Fig. 1).Nevertheless, a prediction of rock mass stress in excess of yield limits, based on elastic models, does not inevitably correspond to actual catastrophic failure of the underground opening. This is fortunate given the depths encountered in modern mining, where much of the ground above mining openings has reached a damage or yield stress threshold at some point in the mining sequence and yet, with the exception of highly stressed ground experiencing rockbursting, shearing or stress buckling, generally remains in place in the short term. This is due to the rock mass' residual tensile load bearing capacity normal to the excavation bound-ary and due to arching to the abutments.Paradoxically, ultimate failure of this damaged ground is often induced by changes in mine geometry which reduce [12±16] rather than increase the stresses across the back or walls as might have been the case in Fig. 1. It is the premise of this paper that the key to this discrepancy between modeled or predicted failure and the actual observed occurrence of failure in under-ground excavations in hard rock is due to the domi-nance of the rock mass's tensile load bearing capacity.However, if combined with abutment relaxation, thein¯uence of gravity can exceed the tensile load bearing capacity of naturally jointed or stress fractured rock masses leading to the type of failure illustrated in Fig. 1. This paper will not attempt to explain the gen-esis of natural fractures and associated rock bridges, Fi nor will it examine the mechanics of formation for boundary parallel stress cracks. The foregoing discus-sion assumes that such damage is omni-present in underground excavations and explains the possible impact on ultimate stability.In this paper we will discuss the nature of residual tensile capacity in jointed or fractured rock masses comparing its capacity to that of economical engin-eered support systems. The e.ect of abutment relax-ation on rock wedge and blocky slabstability is demonstrated. Di.erent mining scenarios are described which may lead to destabilizing relaxation. The vous-soir arch analogue is used to further demonstrate the importance of boundary normal tensile capacity and abutment relaxation. The voussoir analogue is then calibrated to correspond with empirical stability guide-lines for rock mass stability. The e.ect of relaxation is further demonstrated in this context. Conclusions：The presence of geometrically unfavourable jointing or rock mass damage due to elastic predictions of overstress does not, in itself, dictate that failure will take place. Neglecting the possibility of dynamic pro-cesses such as compression-induced buckling, degra-dation of residual tensile strength or abutment relaxation is often required before failure can take place.Rock masses are inherently discontinuous due to natural jointing or induced fracturing. It is often erro-neous to assume that this fracturing is fully persistent. In massive to moderately jointed rock residual tensile load bearing strength arising from incomplete fractur-ing or from rock bridges separating non-persistent joining is a key factor in the control of ultimate grav-ity driven failure of jointed or stress damaged ground.Very little rock bridge cross-sectional area (less than 1% in most cases) is required in hard rocks to replace most arti®cial support systems. The time dependency of this residual tensile strength due to stress corrosion and atmospherically induced crack growth controls stand-up time and mandates the use of support sys-tems in most underground excavations. Sti. Support such as grouted rebar can suppress dilation strains and preserve some of this internal tensile strength, contri-buting to a reduction in both short term and long term support requirements. There is great economic advantage to selecting, as part of a multi-component support system, sti. elements which can preserve the rock mass internal tensile capacity. Careful blast damage control is also an obvious advantage. Early installation of shotcrete or spray-on linings in a dry rock mass at depth can reduce the impact of atmos-pheric e.ects and time dependent stress corrosion on stressed rock bridges.Boundary parallel relaxation is another dominating factor in delayed mining induced failure of spans in underground excavations, signi®cantly shifting conven-tional no-support limits so that smaller spans or ad-ditional support are required. Dangerous abutment relaxation can occur even at depth, driven by un-favourable stress ratios, complex mine geometries, abutment damage, intersection development and undercutting. Abutment relaxation increases support demands by reducing the natural ability of the rock mass to transfer loads to the abutments through arch-ing. In addition, boundary normal stress relaxation has been shown to reduce the capacity of frictional support systems, exacerbating ground control pro-blems.A voussoir beam analogue was used to illustrate the importance of internal boundary normal tensile strength and of abutment relaxation in controlling the stability of spans in laminated rock masses. The results of the voussoir simulation were used to modify empiri-cal stope design limits, accounting for abutment relax-ation. A few millimetres of hangingwall or back abutment relaxation can signi®cantly shift the no-sup-port limit, inducing failure in previously stable spans. It is therefore important to sequence development and stope extraction properly to minimize this relaxation and tominimize the size of secondary stopes. The creation of high relaxation geometries, such as hanging-wall undercutting, must be avoided.6．在地下挖掘机制拉伸强度和桥墩松弛的失效控制摘要：地下洞室群的不稳定可能是典型的评估通常基于屈服应力驱动的失败和破裂准则和极限平衡分析构造控制失败。
毕业后是找工作还是自己创业的英语作文
毕业后是找工作还是自己创业的英语作文全文共3篇示例，供读者参考篇1The Leap into the Future: Finding a Job or Starting My Own Business?As I stand on the precipice of my college graduation, a multitude of paths lay before me, each promising its own set of challenges and rewards. The decision that weighs heavily on my mind is whether to seek employment within an established company or to embark on the daunting yet exhilarating journey of entrepreneurship. This crossroad, a pivotal moment in my life, demands careful contemplation and a deep understanding of my aspirations, strengths, and the ever-evolving landscape of the professional world.The allure of a stable career path, with its promise of a steady income and structured career progression, is undeniably appealing. Finding employment within a reputable organization offers the invaluable opportunity to gain hands-on experience, refine my skills, and immerse myself in the corporate culture. The guidance of seasoned professionals and the potential formentorship could prove invaluable in shaping my professional growth and development. Furthermore, the financial security that accompanies a regular paycheck cannot be overlooked, especially in the initial stages of my post-graduate life when establishing a solid financial foundation is paramount.However, the siren call of entrepreneurship resonates deeply within me, igniting a fire of ambition and a thirst for autonomy. The prospect of turning my innovative ideas into tangible reality, of creating something truly unique and leaving an indelible mark on the world, is an exhilarating notion that fuels my entrepreneurial spirit. As an entrepreneur, I would have the freedom to chart my own course, to make decisions that align with my values and vision, and to forge a legacy that extends far beyond the confines of a traditional corporate setting.Yet, the path of entrepreneurship is fraught with uncertainties and risks. The financial burden of launching a venture, securing funding, and navigating the complexities of business operations can be daunting. Failure looms as a constant specter, and the demands of being a self-starter, wearing multiple hats, and shouldering the weight of every decision could prove overwhelming. Nonetheless, the potential rewards –the ability to shape my own destiny, the thrill of innovation, andthe prospect of achieving financial independence – are alluring siren songs that beckon me ever closer to the entrepreneurial realm.As I wrestle with this pivotal decision, I find solace in the knowledge that both paths offer invaluable lessons and opportunities for growth. Whichever route I choose, I must approach it with unwavering determination, resilience, and a willingness to embrace the challenges that inevitably arise. Seeking employment within an established company could provide the foundation upon which to hone my skills, gain industry insights, and perhaps even cultivate the resources necessary to eventually pursue my entrepreneurial aspirations. Conversely, taking the entrepreneurial plunge could unleash a torrent of creativity and innovation, allowing me to blaze a trail that defies conventional boundaries and redefines success on my own terms.In the end, the decision may not be as binary as it initially appears. Perhaps the true path lies in striking a harmonious balance, exploring entrepreneurial endeavors while simultaneously gaining invaluable experience within the corporate realm. Or, I may choose to immerse myself fully in theworld of entrepreneurship, embracing the risks and uncertainties as catalysts for personal and professional growth.Regardless of the path I ultimately choose, one thing remains certain: the future is an uncharted territory rife with both challenges and opportunities. It is up to me to navigate these uncharted waters with courage, conviction, and an unwavering commitment to continuous learning and growth. Whether I find myself climbing the corporate ladder or forging my own entrepreneurial path, the journey ahead promises to be an exhilarating adventure, one that will shape not only my professional trajectory but also my personal development and self-discovery.As I stand poised on the threshold of this new chapter, I am reminded of the wise words that have guided me thus far: "The future belongs to those who believe in the beauty of their dreams." With this mantra etched into my heart, I will fearlessly embrace the unknown, trusting in my ability to adapt, learn, and ultimately, to thrive in whichever path I choose to tread.篇2To Work or Not to Work? That is the QuestionAs I approach the completion of my studies, I find myself at a crossroads – should I pursue the conventional path of seeking employment with an established company, or should I take the road less traveled and embark on an entrepreneurial journey? This decision carries immense weight, as it will undoubtedly shape the trajectory of my professional life and personal growth.The allure of a stable job with a reputable organization is undeniable. After years of hard work and dedication to my academic pursuits, the prospect of securing a position that aligns with my field of study holds an irresistible appeal. The promise of a steady income, structured career progression, and the opportunity to hone my skills under the guidance of seasoned professionals is enticing. Moreover, the security and benefits that come with traditional employment provide a sense of comfort and stability that many crave in an increasingly unpredictable world.However, the siren call of entrepreneurship beckons with an equally compelling proposition. The idea of being my own boss, charting my own course, and turning my innovative ideas into tangible reality is exhilarating. The prospect of creating something from scratch, nurturing it, and watching it blossom into a successful venture ignites a fire within me that cannot beeasily extinguished. Unlike the confines of a corporate structure, entrepreneurship offers the freedom to explore uncharted territories, challenge the status quo, and leave an indelible mark on the world.Yet, the path of entrepreneurship is not without its inherent risks and challenges. The sobering reality is that the vast majority of startups fail, often due to a lack of resources, planning, or market demand. The uncertainty of income, the relentless pursuit of funding, and the constant pressure to innovate and stay ahead of the competition can be daunting. Furthermore, the weight of sole responsibility for the success or failure of the venture rests squarely on my shoulders, a burden that can be both empowering and overwhelming.As I weigh these options, I find myself drawn to the allure of entrepreneurship, fueled by a burning desire to create something truly remarkable and leave a lasting legacy. The journey may be arduous, fraught with obstacles and setbacks, but the potential rewards are invaluable. The opportunity to turn my vision into reality, to challenge the status quo, and to forge my own path is a siren call that resonates deeply within me.However, I am also cognizant of the importance of gaining practical experience and honing my skills before embarking onsuch a daunting endeavor. Perhaps the most prudent path forward is to initially seek employment within an established company, leveraging the wealth of knowledge and resources at my disposal to refine my abilities and gain a deeper understanding of the intricacies of my chosen field.During this period of professional growth, I can simultaneously nurture my entrepreneurial aspirations, dedicating my spare time to developing and refining a comprehensive business plan, conducting market research, and exploring potential avenues for funding and support. Thisdual-track approach would allow me to mitigate the risks associated with immediate entrepreneurial pursuits while laying the groundwork for a future venture.Ultimately, the decision to pursue employment or entrepreneurship is a deeply personal one, influenced by a myriad of factors, including risk tolerance, financial stability, and personal aspirations. For me, the siren song of entrepreneurship resonates profoundly, but I recognize the wisdom in tempering my ambitions with practical experience and a solid foundation.As I stand at this crossroads, I am filled with a sense of excitement and anticipation for the journey ahead, whichever path I choose to tread. The world is brimming with opportunities,and I am determined to seize them, embracing the challenges and triumphs that lie ahead with equal fervor. For now, I will continue to nurture my entrepreneurial dreams while seeking employment that aligns with my passions and aspirations, ever mindful that the road less traveled may lead to the greatest adventures of all.篇3To Find a Job or Start a Business After Graduation? A Tough DecisionAs graduation day approaches, I find myself faced with one of the biggest decisions of my young life so far - should I seek out traditional employment and find a job, or take the riskier path of entrepreneurship and start my own business? It's a dilemma that has kept me up many a night pondering the pros and cons of each option.On one hand, the safe and predictable route of getting a job holds a certain appeal. With a steady paycheck and benefits like health insurance and retirement plans, I could quickly achieve a level of financial security and stability. I wouldn't have to deal with the daily stresses of running a business - managing employees, dealing with cash flow issues, worrying aboutmaking payroll. I could simply show up, do my job to the best of my ability, and leave the office responsibilities behind at the end of the workday. Having a clear delineation between work and personal life is attractive.Furthermore, by starting off at an established company, I could potentially benefit from mentorship opportunities, robust training programs, and the ability to learn from experienced professionals in my field. The resources and knowledge I could gain would be invaluable as I seek to grow my skills and advance my career over time. Job security could allow me to really hone my craft without the distractions that come with bootstrapping a startup.However, the prospect of entrepreneurship tugs at me persistently. There's something immensely alluring about being my own boss and bringing my own unique vision to life through a business. Instead of just being a cog in someone else's machine, I could build something from the ground up and have full autonomy in all decision making. The idea of unlimited income potential, rather than being capped at a salary, is tantalizing.As an entrepreneur, I would have the freedom to set my own schedule and lifestyle in a way that may be impossible when working for others. If my business was successful, I could designmy ideal work-life balance without having to get approvals for vacation days or justify my personal needs to managers and HR departments. My level of effort and hustle would dictate my own outcomes, both positive and negative, rather than happening at the whim of corporate shareholders.Then there's the romantic notion of entrepreneurship itself - taking an original idea and turning it into a living, breathing entity that provides value to people. The ability to be creative on a daily basis and work on something I'm truly passionate about rather than just punching a clock is deeply appealing. Even the challenges and struggles of building a business from scratch hold a strange attraction for me as I crave that sense of meaning that comes from pouring your heart into your own enterprise.Truthfully, both paths contain a great deal of uncertainty at this stage in my journey. If I seek out a traditional job, will I end up stuck in corporate drudgery doing something I have no passion for? Will I get pigeon-holed or become expendable as the company's needs change? On the other hand, would my business idea even prove viable in the real world? Could I attract funding and customers? Would the intense work hours and inevitable obstacles along the way make the sacrifice worthwhile or just lead to disappointment and burnout?In the end, I don't think there's necessarily one right answer that fits every person. So much depends on individual personality traits, goals, risk tolerance, resources, and overall life situation. For some, the appeal of a stable job and predetermined path is perfect. For others like myself who crave autonomy and the opportunity to innovate, entrepreneurship could be the ideal pursuit - despite the added risk and responsibility.Perhaps the ideal scenario is to start off with a job after graduation to build relevant skills, industry knowledge, and personal savings. Then, once I have more experience and financial resources under my belt, I could eventually make the leap into entrepreneurship from a position of strength rather than struggling to get a bootstrapped business off the ground immediately out of school. Or possibly I could start a side business venture while still employed to test the waters and validate my ideas before taking the full plunge into being afull-time founder.No matter which direction I decide, I know I have the determination and hunger for success to make either path work. The road ahead won't be easy, but nobody achieves their dreams through complacency. With careful planning, calculatedrisk-taking, and a wholehearted effort, I'm confident I can craft a rewarding career for myself - whether that's through gainful employment or ambitious entrepreneurship. The choice may be a tough one, but I welcome the challenge of shaping my own destiny.。
- 1、下载文档前请自行甄别文档内容的完整性，平台不提供额外的编辑、内容补充、找答案等附加服务。
- 2、"仅部分预览"的文档,不可在线预览部分如存在完整性等问题,可反馈申请退款(可完整预览的文档不适用该条件!)。
- 3、如文档侵犯您的权益，请联系客服反馈,我们会尽快为您处理(人工客服工作时间：9:00-18:30)。
We discuss the formation and detection at the next linear e+e− collider of bound states of level1 Kaluza-Klein excitations BKK within a scenario of universal extra-dimensions (UED). In order to obtain the threshold cross-section, we employ the Green function method which is known to properly describe the peaks below threshold and to yield a net increase in the continuum region (above threshold) relative to the naive Born cross-section. The overall effect is roughly threefold and a relatively large number of events is expected Nevents ≈ 104 for mBKK = 1 TeV at the anticipated annual integrated luminosity of L0 = 100 fb−1.
Equally important turn out to be the lower bounds from the inclusive radiative decay B¯ → Xsγ. It has been shown in ref. [18] that a refined analysis includ-
variance with the conclusions of a recent paper [17] where
an analysis of LEP data including data from above the
Z pole and two loop electro-weak corrections to the ∆ρ parameter pointed to R−1 800 (at 95% C.L.).
the Higgs mass. A recent refined analysis [15] taking into
account sub-leading contributions from the new physics
as well as two-loop corrections to the standard model ρ parameter finds that R−1 600 GeV for a light Higgs
from analysis of electro-weak precision measurements
performed at the Z pole (LEP II). An important fea-
ture of these type of constraints is their dependence on
lab Tevatron it will be possible to test compactification scales up to R−1 ∼ 500 GeV at least within some partic-
ular scenario [12, 13, 14].
Lower bounds on the compactification radius arise also
ref. [9, 10]. In particular KK production has been con-
sidered both at the Cern large hadron collider (LHC) and
at the next linear collider (ILC). Direct searches of KK
PACS numbers: 12.60.-i, 11.10.St, 14.80.-j
arXiv:0804.3917v2 [hep-ph] 25 Apr 2008
I. INTRODUCTION
It is well known that as early as 1921 Theodore Kaluza proposed a theory that was intended to unify gravity and electromagnetism by considering a space-time with one extra space-like dimension [1]. A few years later Oscar Klein proposed that the extra space dimension (the fifth dimension) is in reality compactified around a circle of very small radius [2]. These revolutionary ideas have thereafter been ignored for quite some time. However recent developments in the field of string theory have suggested again the possibility that the number of space time dimensions is actually different from D = 4 (indeed string theory models require D = 11, i.e. seven additional dimensions). In 1990 it was realized [3] that string theory motivates scenarios in which the size of the extra dimensions could be as large as R ≈ 10−17 cm (corresponding roughly to electro-weak energy scale (≈ TeV) contrary to naive expectations which relate them to a scale of the order of the Planck length LP ≈ 10−33 cm (corresponding to the Planck mass MP = c/G ≈ 1019 GeV). See also [4].
Subsequently two approaches have been developed to discuss the observable effects of these, as yet, hypothetical extra dimensions. One possibility is to assume that the extra space-like dimensions are flat and compactified to a ”small” radius. This is the so called ADD model [5] where only the gravitational interaction is assumed to propagate in the extra-dimension. A second possibility is contemplated in the Randall-Sundrum type of models where the extra dimensions do have curvature and are embedded in a warped geometry [6, 7].
ticle (LKP) which typically is the level 1 photon. Many
aspects of the phenomenology of these KK excitations
have been discussed in the literature. For reviews see
m2
X (n)
≈
m2
ortant aspect of the
UED model is that it provides a viable candidate to the
Cold Dark Matter. This would be the lightest KK par-
thus keeping the model within the reach of the Tevatron
run II. The finding of this precision analysis are in qual-
itative agreement with previous results [16], but are at
Threshold production of meta-stable bound states of Kaluza Klein excitations in Universal Extra Dimensions
N. Fabiano and O. Panella Istituto Nazionale di Fisica Nucleare, Sezione di Perugia, Via A. Pascoli I-06123, Perugia, Italy
Universal extra-dimensional models were introduced in ref. [8] and are characterized, as opposed to the ADD model, by the fact that all particles of the Standard Model (SM) are allowed to propagate in the (flat) extra space dimensions, the so called bulk. Here to each SM particle X(0) corresponds in this model a tower of KaluzaKlein states X(n) (KK-excitations), whose masses are related to the size of the compact extra dimension introduced and the mass of the SM particle via the relation