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J.Nanopart.Res.,2009,11,1513–Rheological behaviour of ethylene glycol-titanate nanotube nano

BRIEF COMMUNICATIONRheological behaviour of ethylene glycol-titanate nanotube nanofluidsHaisheng Chen ÆYulong Ding ÆAlexei Lapkin ÆXiaolei FanReceived:11July 2008/Accepted:4February 2009/Published online:26February 2009ÓSpringer Science+Business Media B.V.2009Abstract Experimental work has been performed on the rheological behaviour of ethylene glycol based nanofluids containing titanate nanotubes over 20–60°C and a particle mass concentration of 0–8%.It is found that the nanofluids show shear-thinning behaviour particularly at particle concentrations in excess of *2%.Temperature imposes a very strong effect on the rheological behaviour of the nanofluids with higher temperatures giving stronger shear thinning.For a given particle concentration,there exists a certain shear rate below which the viscosity increases with increasing temperature,whereas the reverse occurs above such a shear rate.The normalised high-shear viscosity with respect to the base liquid viscosity,however,is independent of temperature.Further analyses suggest that the temperature effects are due to the shear-dependence of the relative contributions to the viscosity of the Brownian diffusion and convection.The analyses also suggest that a combination of particle aggregation and particle shape effects is the mechanism for the observed high-shear rheological behaviour,which is also supported by the thermal conductivity measure-ments and analyses.Keywords Rheological behaviour ÁEthylene glycol ÁTitanate nanotube ÁNanofluid ÁThermal conductivityNanofluids are dilute suspensions of particles with at least one dimension smaller than about 100nm (Choi 1995).Such a type of materials can be regarded as functionalized colloids with special requirements of a low-particle loading,a high-thermal performance,favourable flow/rheolgocial behaviour,and a great physical and chemical stability over a wide range of process and solution chemistry conditions.Nano-fluids have been shown to be able to enhance heat transfer (Choi 1995;Wang and Mujumdar.2007),mass transfer (Krishnamurthy et al.2006),and wetting and spreading (Wasan and Nikolov 2003),and have been a hot topic of research over the past decade (Wang and Mujumdar 2007;Keblinski et al.2005).Most published studies have focused on the heat transfer behaviour including thermal conduction (Choi 1995;Wang et al.1999;Wang and Mujumdar 2007;Keblinski et al.2005;Eastman et al.2001;He et al.2007;Ding et al.2006),phase change (boiling)heat transfer (Das et al.2003;Pak and Cho 1998),and convective heat transfer (Wang and Mujumdar 2007;Keblinski et al.2005;He et al.2007;Ding et al.2006,Chen et al.2008;Prasher et al.2006a and Yang et al.2005).Only few studies have been devoted to the rheological behaviour ofH.Chen ÁY.Ding (&)Institute of Particle Science and Engineering,University of Leeds,Leeds,UK e-mail:y.ding@pkin ÁX.FanDepartment of Chemical Engineering,University of Bath,Bath,UKJ Nanopart Res (2009)11:1513–1520DOI 10.1007/s11051-009-9599-9nanofluids(He et al.2007;Chen et al.2008;Prasher et al.2006a,b;Kwak and Kim2005;Lee et al.2006), although there is a large body of literature on suspensions rheology;see for example,Russel et al. (1991);Chow(1993);Petrie(1999),Larson(1999); Goodwin et al.(2000)l;Mohraz et al.(2004);Larson (2005);Egres and Wagner(2005);Abdulagatov and Azizov(2006).Particularly,there is little in the literature on the effect of temperature on the rheo-logical behaviour of nanofluids.Clearly,there is a gap in the current rheological literature for this type offluids.Furthermore,recent work has shown that the thermal behaviour of nanofluids correlates well with their rheological behaviour(Prasher et al.2006a, b;Chen et al.2007a;Abdulagatov and Azizov2006). In a recent study,we investigated systemically the rheological behaviour of ethylene glycol(EG)based spherical TiO2nanofluids(Chen et al.2007b).The results show that the nanofluids are Newtonian over a shear rate range of0.5–104s-1and the shear viscosity is a strong function of temperature,particle concentration and aggregation microstructure.This work is concerned about the rheological behaviour of EG based nanofluids containing titanate nanotubes (TNT).The specific objectives of the work are to investigate the effects of particle shape,particle concentration and temperature on nanofluids viscosity, and to understand the relationship between the rheo-logical behaviour and the effective thermal conductivity of nanofluids.It is for thefirst time that the rheological behaviour of a highly viscous EG based TNT nanofluids is investigated in a systematic manner.As will be seen later,the results of this work provide further evidence that the rheological measure-ments could provide information of particle structuring for predicting the effective thermal conductivity of nanofluids.The EG-TNT nanofluids used in this work were formulated by using the so-called two-step method with EG purchased from Alfa Aesar and TNT synthesized in our labs using a method described elsewhere(Bavykin et al.2004).The details of nanofluids formulation can be found elsewhere(Wen and Ding2005;He et al.2007;Chen et al.2007b). The TNT particles have a diameter(b)of*10nm and a length(L)of*100nm,giving an aspect ratio of(r=L/b)of*10.To avoid complications in interpreting the experimental results,no dispersants/ surfactants were used in the formulation.The nanofluids formulated were found stable for over 2months.The rheological behaviour of the nano-fluids was measured by using a Bolin CVO rheometer (Malvern Instruments,UK)over a shear rate range of 0.03–3,000s-1,a nanoparticle mass concentration of w=0–8%,and a temperature range of20–60°C (293–333K).The nanofluids were characterised for their size by using a Malvern Nanosizer(Malvern Instruments,UK)and a scanning electron microscope (SEM).The average effective particle diameter was found to be*260nm for all nanofluids formulated. This size is much larger than the equivalent diameter of the primary nanoparticles due to aggregation;see later for more discussion.Note that the particle size characterisation was performed both before and after the rheological measurements and no detectable changes to particle size were found.Figure1shows the viscosity of pure EG and EG-TNT nanofluids as a function of shear rate at 40°C.The results at other temperatures are similar.It can be seen that the EG-TNT nanofluids exhibit highly shear-thinning behaviour particularly when the TNT concentration exceeds*2%.Such behaviour is different from the observed Newtonian behaviour of EG-TiO2nanofluids containing spherical nanoparti-cles over similar shear rate range(Chen et al.2007b) where the base liquid,EG,is the same as that used in the current wok.The behaviour is similar to the observations of carbon nanotube nanofluids(Ding et al.2006)and CuO nanorod nanofluids(Kwak and Kim2005),although there are important differencesbetween them such as temperature dependence as will be discussed later.The shear-thinning behaviour of well-dispersed suspensions can be interpreted by the structuring of interacting particles(Doi and Edwards1978a,b and Larson1999).In a quiescent state,a rod-like particle has three types of motion due to Brownian diffusion: rotational(end-over-end)motion around the mid-point and translational motion in parallel or perpendicular to the long axis.For dilute suspensions with a number density,c,ranging between0and1/L3or volume fraction,u,ranging between0and1/r2),the average spacing between the particles is larger than the longest dimension of the rod,and zero shear viscosity can be approximated by gð0Þ%g0ð1þAÁcL3Þwith g0the base liquid viscosity and A,a numerical constant(Doi and Edwards1978a).For suspensions with 1/L3\c\1/bL2or1/r2\f/\1/r,the rod-like particles start to interact.The rotational motion is severely restricted,as well as the translational motion perpendicular to the long axis,and the zero shear viscosity can be estimated by gð0Þ%g0ð1þðBcL3Þ3Þ; with B a numerical constant(Doi and Edwards1978b). As a consequence,the zero shear viscosity can be much greater than the base liquid viscosity.The large viscosity is due to the rod-like shape effect and the viscosity is very sensitive to shear,which tends to align particles and hence the shear-thinning behaviour as shown in Fig.1.Note that the above mechanism can give a qualitative explanation for the experimental observations at low-shear rates and the shear-thinning behaviour as shown in Fig.1,it does not explain the high-shear viscosity of the nanofluids,which will be discussed later.It should also be noted that the criteria for classifying nanofluids given above need to be modified due to the presence of aggregates;see later for more discussion.Figure2shows the shear viscosity of4.0%EG-TNT nanofluids as a function of shear rate at different temperatures.The results under other concentrations are similar.It can be seen that the temperature has a very strong effect on the rheological behaviour of nanofluids with higher temperatures giving stronger shear thinning.For shear rates below*10s-1,the shear viscosity increases with increasing temperature, whereas the trend is reversed when the shear rate is above*10s-1.As mentioned above,this behaviour was not observed for carbon nanotube(Ding et al. 2006)and CuO nanorod(Kwak and Kim2005)nanofluids and we have not seen reports on such behaviour for nanofluids in the literature;see later for more discussion on the underlying mechanisms. Figure2also shows that the strongest shear thinning occurs at40–60°C,whereas very weak-shear thinning takes places at20–30°C.It is also noted that the shear viscosity of nanofluids at all temperatures investigated approaches a constant at high-shear rates.If the high-shear viscosity is plotted against temperature,Fig.3is obtained where the shear rate corresponding to the high-shear viscosity is taken as *2,000s-1.An inspection of all the data indicates that theyfit the following equation very well:ln g¼AþBÂ1000=TþCðÞð1Þwhere g is the shear viscosity(mPaÁs),T is the absolute temperature(K),and A,B and C areconstants given in Table1.Equation(1)takes a similar format as that widely used for liquid viscosity (Bird et al.2002)and for EG based nanofluids containing spherical particles(Chen et al.2007b).If the measured high-shear viscosity is normalized with respect to the shear viscosity of the base liquid, the relative increaseðg i¼ðgÀg0Þ=g0Þof the high-shear viscosity is found to be only a function of concentration but independent of temperature over the temperature range investigated in this work.The relative increments in the shear viscosities of nano-fluids containing0.5%,1.0%,2.0%,4.0%and8.0% particles are 3.30%,7.00%,16.22%,26.34%and 70.96%,respectively.Similar temperature indepen-dence of the shear viscosity was also observed for EG-TiO2and water-TiO2nanofluids containing spherical nanoparticles(Chen et al.2007b).The experimentally observed temperature depen-dence can be interpreted as follows.Given the base liquid and nanoparticles,the functional dependence of viscosity on shear rate is determined by the relative importance of the Brownian diffusion and convection effects.At temperatures below*30°C,the contribu-tion from the Brownian diffusion is weak due to high-base liquid viscosity.As a consequence,the shear dependence of the suspension is weak(Fig.2).The contribution from the Brownian diffusion becomes increasingly important with increasing temperature particularly above40°C due to the exponential dependence of the base liquid viscosity on temperature (Fig.3).At very high-shear rates,the Brownian diffusion plays a negligible role in comparison with the convective contribution and hence independent of the high-shear viscosity on the temperature.We now start to examine if the classical theories for the high-shear viscosity predict the experimental measurements(note that there is a lack of adequate theories for predicting the low shear viscosity).Figure4shows the shear viscosity increment as a function of nanoparticle volume concentration together with the predictions by the following Brenner &Condiff Equation for dilute suspensions containing large aspect ratio rod-like particles(Brenner and Condiff1974):g¼g01þg½ uþO u2ÀÁÀÁð2Þwhere the intrinsic viscosity,½g ;for high-shear rates has the following form(Goodwin and Hughes2000):½g ¼0:312rln2rÀ1:5þ2À0:5ln2rÀ1:5À1:872rð3ÞAlso included in Fig.4are the data for EG-TiO2 nanofluids with spherical nanoparticles(Chen et al. 2007b)and predictions by the Einstein Equation (Einstein1906,1911)for dilute non-interacting suspensions of spherical particles,g¼g01þ2:5uðÞ: It can be seen that both the Einstein and Brenner& Condiff equations greatly underpredict the measured data for the EG-TNT nanofluids.The high-shear viscosity of EG-TNT nanofluids is much higher than that of the EG-TiO2nanofluids containing spherical nanoparticles,indicating a strong particle shape effect on the shear viscosity of nanofluids.Although the shear-thinning behaviour of the nanofluids could be partially attributed to the structuring of interacting rod-like particles,the large deviation between the measured high-shear viscosity and the predicted ones by the Brenner&Condiff equation cannot fully be interpreted.In the following,an attempt is made to explain the experimental observations from the viewpoint of aggregation of nanaoparticles,which have been shown to play a key role in thermal behaviour of nanofluids in recent studies(Wang et al. 2003;Xuan et al.2003;Nan et al.1997;Prasher et al. 2006a,b;Keblinski et al.2005).Such an approach is also supported by the SEM and dynamic lightTable1Empirical constants for Eq.(1)a Maximum discrepancies;b Minimum discrepancies Concentration(wt%)A B C MaxD a(%)MinD b(%)0.0-3.21140.86973-154.570.62-1.440.5-3.42790.94425-148.490.93-0.471.0-2.94780.81435-159.14 1.11-0.692.0-2.2930.65293-174.57 1.64-0.694.0-2.63750.7574-165.820.99-0.948.0-2.73140.93156-145.010.88-1.57scattering analyses,which,as mentioned before, show clear evidence of particle aggregation.According to the modified Krieger-Dougherty equation(Goodwin and Hughes2000;Wang et al. 2003;Xuan et al.2003;Nan et al.1997),the relative viscosity of nanofluids,g r,is given as:g r¼1Àu a=u mðÞÀ½g u mð4Þwhere u m is the maximum concentration at which the flow can occur and u a is the effective volume fraction of aggregates given by u a¼u=u ma with u ma the maximum packing fraction of aggregates.As aggre-gates do not have constant packing throughout the structure,the packing density is assumed to change with radial position according to the power law with a constant index(D).As a result,u a is given as u a¼uða a=aÞ3ÀD;with a a and a,the effective radii of aggregates and primary nanoparticles,respectively. The term D is also referred as the fractal index meaning the extent of changes in the packing fraction from the centre to the edge of the aggregates.Typical values of D are given in normal textbook as D= 1.8–2.5for diffusion limited aggregation(DLA)and D=2.0–2.2for reaction limited aggregation(RLA); see for example Goodwin and Hughes(2000).For nanofluids containing spherical nanoparticles,the value of D has been shown experimentally and numerically to be between1.6and1.8(Wang et al. 2003,Xuan et al.2003)and between1.8and2.3, respectively(Waite et al.2001).A typical value of 1.8is suggested for nanofluids made of spherical nanoparticles(Prasher et al.2006a,b).However,little research has been found on the fractal index for nanofluids containing rod-like nanoparticles.The colloid science literature suggests a fractal index of 1.5–2.45for colloidal suspensions depending on the type of aggregation,chemistry environment,particle size and shape and shearflow conditions(Haas et al. 1993;Mohraz et al.2004;Hobbie and Fry2006; Micali et al.2006;Lin et al.2007).In a recent study, Mohraz et al.(2004)investigated the effect of monomer geometry on the fractal structure of colloi-dal rod aggregates.They found that the fractal index is a non-linear function of the monomer aspect ratio with the D increasing from*1.80to*2.3when the aspect ratio of the rod-like nanoparticles increases from1.0to30.6.Based on the above,a value of D=2.1is taken for nanofluids used in this work (Mohraz et al.2004,Lin et al.2007).Although the fractal model may appear to simplify the complexity of microstructures in aggregating systems containing rod-like particles,excellent agreement between the model prediction and experimental measurements exists when a a/a=9.46;see Fig.4.Here the aggregates are assumed to formflow units of an ellipsoidal shape with an effective aspect ratio of r a¼L a=b a;where L a and b a are the effective length and diameter,respectively.In the calculation,a typical value of u m of0.3is taken(Barnes et al.1989),and the intrinsic viscosity[g]is calculated by Eq.(3).It is to be noted that the aggregate size thatfits well to the rheological data(Fig.4)is consistent with the particle size analyses using both the SEM and the Malvern Nanosizer.A comparison between the EG-TNT data (a a/a=9.46,D=2.1,u m=0.30)and the EG-TiO2 data(a a/a=3.34,D=1.8,u m=0.605)(Chen et al. 2007b)in Fig.4suggests that the larger aggregate size in TNT nanofluids be an important factor responsible for the stronger shear-thinning behaviour and higher shear viscosity of TNT nanofluids.An inspection of Eq.(4)indicates that the effec-tive volume fraction u a u a¼u a a=aðÞ3ÀDis much higher than the actual volume fraction(u).This leads to the experimentally observed high-shear viscosity even for very dilute nanofluids,according to the classification discussed before.As a consequence,the demarcations defining the dilute and semi-concen-trated dispersions should be changed by using the effective volume fraction.The model discussed above can also provide a macroscopic explanation for the temperature indepen-dence of the high-shear viscosity.From Eq.(4),one can see that the relative high-shear viscosity depends on three parameters,the maximum volume fraction, u m,the effective volume fraction,u a and the intrinsic viscosity,[g].For a given nanofluid at a temperature not far from the ambient temperature,the three parameters are independent of temperature and hence the little temperature dependence of the relative shear viscosity.Microscopically,as explained before,the temperature-independent behaviour is due to negligi-ble Brownian diffusion compared with convection in high-shearflows.To further illustrate if the proposed aggregation mechanism is adequate,it is used to predict the effective thermal conductivity of the nanofluids by using the following conventional Hamilton–Crosser model(H–C model)(Hamilton and Crosser1962):k=k0¼k pþðnÀ1Þk0ÀðnÀ1Þuðk0Àk pÞk pþðnÀ1Þk0þuðk0Àk pÞð5Þwhere k and k0are,respectively,the thermal conductivities of nanofluids and base liquid,n is the shape factor given by n=3/w with w the surface area based sphericity.For TNT used in this work,the sphericity w is estimated as0.6(Hamilton and Crosser1962).For suspensions of aggregates,the above equation takes the following form:k=k0¼k aþðnÀ1Þk0ÀðnÀ1Þu aðk0Àk aÞa0a0að6Þwhere k a is the thermal conductivity of aggregates.To calculate k a,Eq.(6)is combined with the following Nan’s model(Nan et al.2003)for randomly dispersed nanotube-based composites:k a=k0¼3þu in½2b xð1ÀL xÞþb zð1ÀL zÞ3Àu in½2b x L xþb z L zð7Þwhere/in is the solid volume fraction of aggregates, b x¼ðk xÀk0Þ=½k mþL xðk tÀk mÞ and b z¼ðk zÀk0Þ=½k mþL zðk tÀk mÞ with k x,k m and k t being the thermal conductivities of nanotubes along trans-verse and longitudinal directions and isotropic thermal conductivity of the nanotube,respectively. In this work,k x,k m and k t are taken the same value as k p for afirst order of approximation due to lack of experimental data,and L x and L z are geometrical factors dependent on the nanotube aspect ratio given by L x¼0:5r2=ðr2À1ÞÀ0:5r coshÀ1r=ðr2À1Þ3=2 and L z¼1À2L x:Figure5shows the experimental results together with predictions by the original H–C model(Eq.5) and revised H–C model(Eq.6).Here the experiment data were obtained using a KD2thermal property meter(Labcell,UK)(Murshed et al.2005;Chen et al. 2008).One can see that the measured thermal conductivity is much higher than the prediction by the conventional H–C model(Eq.5),whereas the modified H–C model taking into account the effect of aggregation(Eq.6)agrees very well with the exper-imental data.The above results suggest that nanoparticle aggregates play a key role in the enhancement of thermal conductivity of nanofluids. The results also suggest that one could use the rheology data,which contain information of particle structuring in suspensions,for the effective thermal conductivity prediction.In summary,we have shown that EG-TNT nano-fluids are non-Newtonian exhibiting shear-thinning behaviour over20–60°C and a particle mass concen-tration range of0–8%,in contrast to the Newtonian behaviour for EG-TiO2nanofluids containing spher-ical particles.The non-Newtonian shear-thinning behaviour becomes stronger at higher temperatures or higher concentrations.For a given particle concen-tration,there exists a certain shear rate(e.g.*10s-1 for4wt%)below which the viscosity increases with increasing temperature,whereas the reverse occurs above such a shear rate.The normalised high-shearviscosity with respect to the base liquid viscosity, however,is found to be independent of temperature. These observations have not been reported in the literature for nanofluids.Further analyses suggest that the temperature effects are due to the shear-depen-dence of the relative contributions to the viscosity of the Brownian diffusion and convection.The analyses also suggest that a combination of particle aggregation and particle shape effects is the mechanism for the observed high-shear rheological behaviour,which is supported not only by the particle size measurements but also by the thermal conductivity measurements and analyses using a combination of the H–C and Nan’s models.The results of this work also indicate that one could use the information of aggregation from the rheological experiments for predicting the effec-tive thermal conductivity of nanofluids. 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斯密悖论解析及其对我国市场条件下道德转型的启迪

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为促进我国市场道德转型,建议加强道德教育、强化法律监管、倡导诚信文化等措施。
通过深入理解斯密悖论,可以在我国市场条件下推动道德规范的提升,并引领道德转型的进程。
【关键词】斯密悖论、道德转型、市场条件、内涵、解析、道德规范、问题、启示、建议、结论1. 引言1.1 斯密悖论简介亚当·斯密(Adam Smith)是经济学领域的开创者之一,被誉为现代经济学之父。
他所著的《国富论》被认为是资本主义经济体系的奠基之作。
在《国富论》中,斯密提出了一种被后人称为“斯密悖论”的经济理论。
该悖论指出,个体追求自身利益的行为,在自由市场中会导致整体社会利益的最大化。
这一理论被认为是自由放任经济学的基石,也为市场经济体系的发展提供了重要的理论支撑。
斯密悖论简单而言就是“看不见的手”的理论,即市场自由自然地进行调节,个体的私利可以最终促进整体的繁荣。
这一悖论强调了市场经济中的个体自由和竞争对经济发展的重要性,同时也引发了很多关于道德与利益的讨论。
在当今社会,斯密悖论的理念依然对经济学界和社会实践有很大的影响。
在我国市场条件下,道德转型的重要性也日益凸显出来,需要我们认真思考和探讨。
正是在这一背景下展现出其重要性和启示意义。
1.2 我国市场条件下道德转型的重要性在我国市场条件下,道德转型的重要性不言而喻。
随着我国市场经济的发展和社会进步,各行各业都面临着道德规范和价值观念的挑战。
在市场经济中,人们往往追求经济利益最大化,导致道德问题频发。
斯密悖论解析及其对我国市场条件下道德转型的启迪

斯密悖论解析及其对我国市场条件下道德转型的启迪斯密悖论被认为是现代经济学中最重要的难题之一,它揭示了市场经济中的道德与利益之间的矛盾和冲突。
斯密悖论指的是自由市场经济在促进个人利益的也产生了道德困境和社会不公。
在我国市场条件下,斯密悖论对道德转型提出了深刻的启迪,我们需要从中汲取教训,促进市场主体的良性竞争和社会的公平正义。
斯密悖论的核心观点是,市场经济下的竞争与合作既能促进个人利益的最大化,也可能导致道德沦丧和社会不公。
亚当·斯密在《国富论》中提出了“看不见的手”理论,强调自由市场经济的自我调节和自我平衡机制,认为个人自私的追求可以最大程度地促进社会福祉。
斯密也意识到了自由市场经济所存在的道德风险,他在《道德情操论》中指出,市场经济下的竞争可能导致个人的自私和自利行为,进而破坏社会的道德秩序和公共利益。
在我国市场条件下,斯密悖论对道德转型提出了重要启示。
我们需要强化市场主体的道德意识和社会责任感。
市场经济的核心是个体的自由选择和竞争,但个体的自私和自利行为也容易引发道德困境和社会不公。
我们应该引导企业家和经营者不仅追求经济利益,还要注重道德品质和社会责任,推动企业文化和商业行为的道德化和规范化,以此避免市场经济下的道德风险和社会矛盾。
我们需要建立健全的法律制度和监管机制,加强对市场行为的规范和监督。
市场经济下的自由竞争虽然能够激发创新和活力,但也容易引发市场操纵、垄断和不当竞争行为,进而损害消费者利益和公共利益。
政府需要建立健全的反垄断法律和监管机构,加强对市场行为的监督和惩治,维护市场秩序和公平竞争,从而防范市场经济下的道德悖论和社会不公。
我们还需要倡导良好的市场伦理和商业道德,促进市场主体的良性竞争和社会的公平正义。
市场经济是建立在合作和竞争的基础上,只有在道德和公平的前提下,市场经济才能够实现可持续发展和社会稳定。
我们应该倡导市场伦理和商业道德,强调公平竞争和诚信经营,构建诚信交易和公平交易的市场环境,从而促进市场主体的健康发展和社会的公平正义。
个人简历表格英语等级六级

个人简历表格英语等级六级篇一:中英文简历模板附件2:中英文简历模版个人简历个人信息姓名:王同学性别:男籍贯:甘肃天水出生日期:1986年7月10日联系方式:931-8912xxx;136931xxxx电子邮箱:job@地址:兰州大学本部20舍301室,730000自我评价教育背景校园活动社会实践基本技能研究经历兴趣爱好表达能力强,可以将新的事务清楚明白地介绍给其他人;求新,乐于接受挑战,承担开拓新的领域的任务;忠诚,具有良好的团队合作能力。
20XX/09-至今兰州大学经济学院?将于20XX年6月获经济学学士学位?兰州大学人民奖学金一等奖,以3.6的学分绩获得经济学院第一名?三次荣获兰州大学人民奖学金二等奖(奖励总成绩名列10%的学生)?入选北京大学中国经济研究中心(ccER)全国“经济学优秀大学生夏令营”(包括港澳台在内,全国顶尖高校仅30名学生入选)?兰州大学经济学院社会实践先进个人20XX/04-20XX/07兰州大学斯密论坛?第一届学生工作组的核心成员之一?协助有关老师完成将这个半官方组织改组为一个学生社团的工作?与的另外两名成员拟定斯密论坛的章程草案?负责斯密论坛第二期“中小企业融资”专题的主持和协调工作20XX/09-至今兰州大学经济学院20XX级经济学x班?学习委员,热心为同学服务?协助各门课的任课老师组织同学在课程中进行专题发言20XX/07-20XX/11独立调查员?于上海,兰州两市的流动人口聚居区进行调研?采访上海市教委的官员?采访成都市青羊区教育局的官员20XX/10-20XX/01兰州市红山民工子弟学校?义务教师,负责英语教学任务?对100余位学生家长进行问卷调查并进行统计分析英语能力?cET-6:520?大学四,六级英语口语考试:B+计算机能力?甘肃省计算机等级考试二级(VisualBasic)?熟练使用SPSS、EXcEL等计量、统计软件论文?财务管理课程论文:蓝田股份(股票代码SH:600709)造假案的财务分析交友,健身ResumePersonalinformationname:wangBinSex:maledateofBirth:July12,1971address:Room301,dormitory20,LanzhouUniversity,Lanzhou,Gansu,7300 00,chinaTelephone:+86-931-8912xxx;+86-136931xxxxE-mail:Education9/20XX-presentLanzhouUniversity?????candidateforBachelorinEconomicsinJune,20XXmajorincorporateFinance ,SchoolofEconomicsRanked2/45inclass,coreGPa:3.3/4awardednationalEx cellentUndergraduateStudentScholarshipawardedExcellentUndergraduate StudentofLanzhouUniversityExperience7/-11/20XXSummerTeam:ExpandJobchannelsforStudents?Gotintouchwith10companies,visited4companiesandfoundtheirtalent demandsmadeagreementswith4companiesthattheywouldrecruitgraduatesinLanzho u?University4/20XX-PresentBusinessSchoolSeminar?FoundedtheBusinessSchoolSeminarwhichaimedtopromotetheacademiccommunicationbetweenstudentsfromdifferentdepartments anchoredthesecondseminar:thefinancialproblemsoftheSmES(smalland? mediumsizedenterprises)10/20XX–1/20XXV olunteerTeacherfortheHongshanSchoolinLanzhou TaughtthecourseofEnglishfortheruralworkers’childrenintheschoolacademiccapability????FluentinEnglish.cET-6:85.5;ToEFL(iBT):98;GRE:1380Graded2ofGansu computerRankExaminationforUniversityStudentsBeProficientinofficeaut omation(microsoftExcel,PowerPoint)andwebSurfingPublications?TheinfluenceofEconomicdensitiesofcityPropersontheinfrastructure investmentbyLocalGovernmentspublishedinScienceandEngineeringResea rch,20XX,2篇二:个人简历空白表格个人简历个人简历姓名:性别:出生日期:户口所在地:工作年限:目前年薪:期望年薪:电子邮件:移动电话:应聘职位:自我评价:对事物有敏锐的洞察力;能很好得与人沟通,具有团队合。
2020南大mba分数线和招生简章

南京大学2019年mba分数线为:总分≥175分,综合≥110分英语≥55分(想知道2020南京大学mba的分数线可以直接与我们咨询)。
下面为大家附上南京大学最新的2020年mba招生简章!南京大学商学院是中国mba教育的先行者,早在1987 年就与美国密苏里大学哥伦比亚分校合作开办mba班,1992 年起率先在新加坡开设mba项目,1993 年起经国务院学位办批准在国内招收mba,二十年多年来累计培养了7000余名经济管理人才。
南京大学商学院mba教育根植百年名校之文化底蕴、依托人文社科之大家云集,发挥经济和管理学科交叉融合之优势,整合政企学研媒等社会资源,以造就“具有创意思维与创新行动(CT&IA - Creative Thinking and Innovative Action)的管理菁英”为目标,通过提升社会责任和拓展全球视野、强化系统思考、融通解决之道为培养路径,为学生提供丰厚的成长土壤和广域的发展空间。
一、培养定位1、目标定位在职MBA:拓展国际视野、提升创意与创新能力,打造“南大系”管理菁英和青年企业家。
国际双学位MBA( NJU-UMSL)培育理论基础扎实、英文沟通娴熟的国际化职业经理人,促进职业发展。
2、培养特色:◆“诚朴雄伟、励学敦行”◆学科融合支撑的课程体系◆兼职导师伙伴计划◆立足“长三角”地区企业转型升级与创新发展二、课程模块:◆先修课程职业素养、职业发展规划、管理思维、中国特色社会主义的理论与实践、商务沟通、商业伦理、语言课程(第二外语)、诚动天下新生Orientation◆基础课程宏观经济学、管理经济学、国际经济学、会计学、数据模型分析与决策、商法、商务英语◆专业方向课群人力资源与组织行为、战略与商业模式、营销与电子商务、财务与金融、创业与投资、物流与运营、国际商务◆实战体验模块案例大赛、行动学习、国际商业大赛、创新创意创业大赛、科技园实验室◆专业核心课程人力资源开发与管理、组织行为学、市场营销学、公司理财、运营管理、战略管理、信息系统与电子商务◆行业前沿模块长三角区域研究、文化创意、奢侈品牌管理、健康管理、互联网金融、NGO 与社会管理、先进制造业、现代农业、创新管理、服务管理、酒店及旅游管理、体育赛事管理等◆人文素养模块从历史看管理、国学与管理、先秦诸子与古代政治思想、南海研究、传统与创新、前沿科学探索与应用、自然辩证法等三、国际交流:南京大学商学院致力于加强海外交流,已与美国、德国、法国、英国、葡萄牙、波兰、日本、韩国、等国家及中国香港、中国台湾等地区的十余所大学建立了双学位项目、交换生项目和短期访学项目。
南京大学经济学院

南京大学经济学院设有经济学系、国际经济贸易系、金融与保险学系、产业经济学系4个系和人口研究所,拥有国家教育部人文社会科学百所重点研究基地“南京大学长江三角洲经济社会发展研究中心”和国家文化部重点研究基地“南京大学文化产业研究所”等研究机构,以及国家985哲学社会科学创新平台“经济发展与转型研究中心”和国家级经济学基础人才培养基地。
经济学院拥有本科专业4个,硕士点(含人口研究所)9个,理论经济学和应用经济学一级学科博士学位授予权,二级学科博士点8个,博士后流动站2个,国家重点学科1个。
经济学院拥有一批具有国外留学背景、学术水平较高、年富力强、团结奋进的师资队伍。
现有教师60名,其中教授24名(博导22名),副教授16名,其中国务院学科评议组成员1人,教育部社会科学委员会委员2人,长江学者特聘教授2人,国家级教学名师2人,教育部新世纪人才5人,人事部等7部委百千万人才工程国家级人选2人。
在人才培养方面,强调“加强基础,注重应用,培养能力,提高素质”,培养了一大批深受社会欢迎的经济专门人才。
经济学院首先在国内开设“硕士工作站”,受到学生和用人单位的热烈欢迎。
近些年,经济学院努力改革课程体系和教学方法,积极引进海外名校教授讲授系列的、先进的经济学课程;与校内其他院系进行联合培养试点;开展了丰富的学术活动,如“银兴杯”五·二?学生学术论文竞赛、斯密论坛、学术餐会等活动,优化了学术氛围,加强了老师与同学之间的交流和联系,取得了非常好的效果;另外,经济学院每年都要举办文化艺术节、运动会、社会实践活动,深受广大教师及学生们的好评,经济学院致力于发挥智力优势为社会服务,每年举办江苏发展高层论坛,邀请国内外高层次学者、政府官员、企业家参与,为国家的经济发展、企业经营提供咨询,被三任省委书记誉为“智力库”、“参谋部”和“桥梁与纽带”;开办研究生课程进修班、高级管理人才培训班、企业总裁高级研修班等,为企业和政府部门提供人才培训、管理策划;与企业建立横向联系,承担了多项科研项目,许多教师还受聘担任省市及大企业的高级顾问,为地区经济发展出谋划策,已成为区域经济发展和政府决策的智囊团。
分工、专业化和产权制度的一般均衡分析
关于分工、专业化和产权制度的一般均衡分析卷首语二百多年前,亚当〃斯密的《国富论》揭示了社会财富之源和自由竞争的市场经济之魅力,推动了人类经济思想的进步。
而今,中国走向社会主义市场经济和实现伟大复兴需要理论创新和思想进步。
南京大学商学院经济学系发起成立斯密论坛(Smithian Forum),由南京大学经济学科国家经济学基础人才培养基地和南京大学长江三角洲经济社会发展研究中心共同主办。
论坛宗旨是研讨中国改革与发展理论与实践问题,并为中国改革与发展作出一份贡献。
其研究成果是《经济发展评论》系列。
该论坛致力于活跃学术气氛、增进学术交流,为提高学生学术研究能力创造良好的环境。
论坛主要面向商学院的研究生与本科生,同时为保证论坛的开放性,热诚欢迎校内外的专家、老师、同学参与。
上述范围内的参与者只要提交一份正式的论文(发表或未发表均可),即可进入论坛,发表自己的观点。
关于分工、专业化和产权制度的一般均衡分析米尔格罗姆(Paul Milgrom,麻省理工学院教授):“这篇论文通过将侵占行为和第三方产权保护内生化, 扩展了杨小凯和黄有光的新兴古典模型(1993)。
此文的杰出贡献在于建立了一个关于古典增长理论的新兴古典模型,强调了专业化和市场的功能,而不是一般的以资本积累来解释经济增长。
这一模型能够清楚地解释君主的行为——她把岁入多数用于加强产权制度而不是个人消费——这是受到了邻国制度竞争的威胁和影响。
这一模型的设计有效地说明了制度经济学和经济史的著名发现。
”杨小凯:“这是新兴古典经济学中的重要文献之一,此文用一般均衡模型论述了国家和宪政制度产生及演进的内生原因, 对由巴泽尔创立的国家经济学和布坎南创立的宪政经济学做出了重要拓展。
”摘要:区别于其他经济学家,布坎南(Buchanan)和巴泽尔(Barzel)分别利用宪政经济学和国家经济学解释了宪政制度和国家产生及演进的原因。
巴泽尔认为,对于私人产权的产生和演进而言,合法的、垄断的、惩罚侵占行为的国家暴力是所必需的。
个人简历表格英语等级六级
个人简历表格英语等级六级篇一:中英文简历模板附件2:中英文简历模版个人简历个人信息姓名:王同学性别:男籍贯:甘肃天水出生日期:1986年7月10日联系方式:931-8912xxx;136931xxxx电子邮箱:job@地址:兰州大学本部20舍301室,730000自我评价教育背景校园活动社会实践基本技能研究经历兴趣爱好表达能力强,可以将新的事务清楚明白地介绍给其他人;求新,乐于接受挑战,承担开拓新的领域的任务;忠诚,具有良好的团队合作能力。
20XX/09-至今兰州大学经济学院?将于20XX年6月获经济学学士学位?兰州大学人民奖学金一等奖,以3.6的学分绩获得经济学院第一名?三次荣获兰州大学人民奖学金二等奖(奖励总成绩名列10%的学生)?入选北京大学中国经济研究中心(ccER)全国“经济学优秀大学生夏令营”(包括港澳台在内,全国顶尖高校仅30名学生入选)?兰州大学经济学院社会实践先进个人20XX/04-20XX/07兰州大学斯密论坛?第一届学生工作组的核心成员之一?协助有关老师完成将这个半官方组织改组为一个学生社团的工作?与的另外两名成员拟定斯密论坛的章程草案?负责斯密论坛第二期“中小企业融资”专题的主持和协调工作20XX/09-至今兰州大学经济学院20XX级经济学x班?学习委员,热心为同学服务?协助各门课的任课老师组织同学在课程中进行专题发言20XX/07-20XX/11独立调查员?于上海,兰州两市的流动人口聚居区进行调研?采访上海市教委的官员?采访成都市青羊区教育局的官员20XX/10-20XX/01兰州市红山民工子弟学校?义务教师,负责英语教学任务?对100余位学生家长进行问卷调查并进行统计分析英语能力?cET-6:520?大学四,六级英语口语考试:B+计算机能力?甘肃省计算机等级考试二级(VisualBasic)?熟练使用SPSS、EXcEL等计量、统计软件论文?财务管理课程论文:蓝田股份(股票代码SH:600709)造假案的财务分析交友,健身ResumePersonalinformationname:wangBinSex:maledateofBirth:July12,1971address:Room301,dormitory20,LanzhouUniversity,Lanzhou,Gansu,7300 00,chinaTelephone:+86-931-8912xxx;+86-136931xxxxE-mail:Education9/20XX-presentLanzhouUniversity?????candidateforBachelorinEconomicsinJune,20XXmajorincorporateFinance ,SchoolofEconomicsRanked2/45inclass,coreGPa:3.3/4awardednationalEx cellentUndergraduateStudentScholarshipawardedExcellentUndergraduate StudentofLanzhouUniversityExperience7/-11/20XXSummerTeam:ExpandJobchannelsforStudents?Gotintouchwith10companies,visited4companiesandfoundtheirtalent demandsmadeagreementswith4companiesthattheywouldrecruitgraduatesinLanzho u?University4/20XX-PresentBusinessSchoolSeminar?FoundedtheBusinessSchoolSeminarwhichaimedtopromotetheacademiccommunicationbetweenstudentsfromdifferentdepartments anchoredthesecondseminar:thefinancialproblemsoftheSmES(smalland? mediumsizedenterprises)10/20XX–1/20XXV olunteerTeacherfortheHongshanSchoolinLanzhou TaughtthecourseofEnglishfortheruralworkers’childrenintheschoolacademiccapability????FluentinEnglish.cET-6:85.5;ToEFL(iBT):98;GRE:1380Graded2ofGansu computerRankExaminationforUniversityStudentsBeProficientinofficeaut omation(microsoftExcel,PowerPoint)andwebSurfingPublications?TheinfluenceofEconomicdensitiesofcityPropersontheinfrastructure investmentbyLocalGovernmentspublishedinScienceandEngineeringResea rch,20XX,2篇二:个人简历空白表格个人简历个人简历姓名:性别:出生日期:户口所在地:工作年限:目前年薪:期望年薪:电子邮件:移动电话:应聘职位:自我评价:对事物有敏锐的洞察力;能很好得与人沟通,具有团队合作精神;对负责的工作会付出全部精力和热情,制定缜密计划,力争在最短时间内将目标达成;喜欢挑战,能在较短时间内适应高压力的工作。
财税专业英语
disequilibrium 失衡externality 外部性,外溢性inflation 通货膨胀market failure 市场失灵,市场失效Medicare 医疗保险制度monopolistic competition 垄断竞争monopoly 垄断natural monopoly 自然垄断negative externalities 负外部性,负外溢性oligopoly 寡头垄断Pareto efficiency 帕累托效率perfect competition 完全竞争positive externalities 正外部性,正外溢性price mechanism 价格机制public financing of private provision 私人提供的公共融资public provision 公共提供subsidy 补贴unemployment 失业club goods 俱乐部产品collective goods 集体产品free-rider problem 搭便车问题global public goods 全球性公共产品nonexcludability 非排他性nonrivalry 非竞争性public bads 公害产品public goods 公共产品publicness 公共性rational ignorance of voters 选民的理性无知shirking 卸责social goods 社会产品special-interest groups 特殊利益集团ability to pay 支付能力accountability 责任autonomy 自治cash expenditure 现金支出departmental agency 部门代理机构exhaustive expenditures 消耗性支出,购买性支出general government expenditure (GGE) 一般政府支出K-12 education K-12教育,指到高中为止的教育体系Macro models 宏观模型Micro models 微观模型Non-Profit Organization(NPO) 非营利性组织postsecondary education 高等教育public law administration(PLA) 公法行政实体public service delivery 公共服务提供real expenditure 实际支出school voucher 教育券state-owned enterprise 国有企业subsidiary 补助Tiebout-type competition 蒂布式竞争transfer payments/expenditures 转移性支出transition country 转型国家transparency 透明度user charging 使用者收费annuity 年金cohort life expectancy 群组预期寿命consumer price index 消费价格指数defined benefit 确定受益制defined contribution 确定供款制financial defined contribution(FDC) 融资的确定供款制fully funded system 完全基金制Great Depression 大萧条internal rate of return 内部收益率modified pay-as-you-go basis 修正的现收现付制non-financial DC 非融资的确定供款制national DC(NDC)scheme 名义确定供款制计划OASDHI(old age,survivors,disability and health insurance) 老年、遗嘱、残疾与健康保险项目OASDI 老年、遗嘱和残疾保险项目OASI(old age and survivors’ insurance) 老年与遗嘱保险pay-as-you-go(PAYG) 现收现付制portfolio 投资组合social security trust fund 社会保障信托基金social security 社会保障SSI(supplementary security income) 补充保障收入universal participation 普遍参与wage ceiling 工资封顶ability-to-pay principle 量能原则,支付能力原则average tax rate(ATR) 平均税率benefit principle 受益原则,利益原则customs duty 关税direct tax 直接税effective tax rates 实际税率(实际税率与法定税率可能不一样,可能是因为税收优惠的缘故,也可能是逃税引起的)estate and gift tax 遗产税与赠与税flat-rate tax 单一税gasoline tax 汽油税general tax 一般税horizontal equity 横向公平indirect tax 间接税individual income tax 个人所得税marginal tax rate(MTR) 边际税率payroll tax 工薪税poll tax 人头税progressive tax rate structure 累进税率结构proportional tax rate structure 比例税率结构regressive tax rate structure 累退税率sale tax 销售税selective tax 选择税statutory tax rate 法定税率tax 税taxation 税,税制tax base 税基tax bracket 税档tax fairness 税收公平tax principle 税收原则tax rate structure 税率结构user fee 使用费vertical equity 纵向公平carroussel 旋转木马避税法consumption tax 消费税corporate profit tax 公司利润税double taxation 重复征税exemption 免税general sales tax 一般销售税goods and services tax 商品劳务税indirect tax 间接税nuisance tax 小额消费品税payroll tax 工资薪金税personal income tax 个人所得税profit tax 利润税progressive tax 累进税refundable 可退税的regressive tax 累退税sales tax 销售税selective sales tax 选择性销售税sin tax 恶税turnover tax 周转税value-added tax(V AT) 增值税zero-rated 零增值税的(货物和劳务)adjusted gross income (AGI) 经调整的毛收入capital gain 资本利得deduction 扣除,扣除额Department of the Treasury (美国)财政部Ministry of Finance 中国财政部EGTRRA (the Economic Growth and Tax Relief Reconciliation Act of 2001) 《经济增长与减税法案》exemption 豁免,免税额flat tax 单一税fundamental tax reform 根本性税制改革itemized deduction 项目扣除joint return 联合申报表standard deduction 标准扣除tax competition 税收竞争tax liability 应付税款tax return 税收申报表taxable income 应税收入territorial taxation 属地税收withholding payment 预缴(税款)支出accelerated depreciation 加速折旧advance corporation tax (ACT) 预缴公司税classical tax system 古典税制capital stock (stock of capital) 资本存量corporate tax (corporation tax) 公司所得税depreciation allowance 折旧提存dividend 红利,股息dividend relief 股利免税double taxation 重复征税economic effective 经济效应excess-profits tax 超额利润税full integration 完全一体化imputation tax system 归集税制incidence 归宿(tax incidence 税收归宿)industrialized country 工业化国家outlays for research and development (R&D) 研发支出partial imputation system 部分归集制partnership method 合伙法split-rate system 分率制real (inflation-adjusted) income 实际收入(经济通货膨胀调整后的收入)shareholder 股东subnational government 中央一下政府,地方政府tax credit 税收抵免tax haven 避税港,税收天堂tax holiday 免税期tax jurisdiction 税收管辖权tax shelter 税务避难所bailout 援助clearing 承兑default 债券拖欠,到期不兑现external debt 外债hyperinflation 恶性通胀inflation 通货膨胀inflation-indexed bond 消除通胀指数的债券internal debt 内债issuance 发行Keynesian 凯恩斯主义municipal bond 市政债券national debt 公债,国债private debt 私债public debt (government debt or national debt) 公债sovereign bond 主权债券structure (债券)结构automatic stabilizers 自动稳定器backfire 事与愿违,产生反效果balanced budget 平衡预算business cycle 经济周期contractionary fiscal policy 紧缩性财政政策countercyclical fiscal policy 反周期财政政策countercyclically 反周期地(指与经济周期既定阶段发展方向相反的,如在经济周期高涨阶段采取通货紧缩政策,以防止通货膨胀鞥问题的出现)crowding out 挤出效应discretionary fiscal policy 相机抉择的财政政策exchange rate appreciation 汇率升值expansionary fiscal policy 扩张性财政政策gross domestic product (GDP) 国内生产总值inside lag 内部时滞macroeconomic policy 宏观经济政策natural rate of 自然······率Ricardian Equivalence 李嘉图等价(定理)supply-side economists 供给学派经济学家twin deficits (预算和贸易)双赤字categorical grant 分类拨款fiscal federalism 财政联邦制,财政联邦主义fiscal transfer 财政转移支付general unconditional grant 一般性的无条件拨款grant 拨款interjurisdictional externality 辖区间的外溢性local public goods 地方性公共产品matching grant 配套拨款national public goods 全国性公共产品Tiebout Model 蒂布模型vote with one’s feet 用脚投票网络资源:英文维基百科辞典网站关于公共部门的互联网杂志/het/经济思想史网站一个推动制度研究的网站/gpgn/topic04.php全球性公共产品研究网络/jbc詹姆斯·布坎南政治经济学研究中心公共选择学会网站/liberty/public_goods_fallacies.html关于公共产品理论不同看法的一个网站世界银行网站,该网站提供大量公共支出改革的文章和资料 OECD网站,该网站提供大量和公共支出有关的文章和资料美国政府网站/spending_review/spend_csr07/spend_csr07_index.cf m 英国财政部网站麻省理工学院经济系网站/feldstein NBER网站Martin Feldstein的文集世界银行网站卡图研究所网站美国国内收入署中国国家税务总局税收知识综合网站/business-and-economy/vat.html提供大量增值税的资料/state.html提供美国州和地方政府的税收材料提供税收政策方面的资料美国城市研究所和布鲁金斯学会合作机构税收政策中心的网站http://www.fourmilab.ch/ustax/ustax.html美国税法在线网站/taxstats/bustaxstats/article/0,,id=97145,00.html该网页提供大量公司所得税统计资料/一个税收新闻网站,提供大量最新税收资讯/美国财政部公债局网站/Services/Public+Debt+Management/index.html世界银行的该网站提供公债管理方面的资料大英百科全书电子版,提供各学科的知识和信息,在经济学科拥有丰富的知识库和最新资讯经济学科电子图书馆,拥有丰富的经济学电子图书资源北京大学中国经济研究中心:/cn/经济学阶梯教室:/国务院研究发展中心:/南京大学商学院斯密论坛:/xueshu。
营销专业论坛网址集锦
相关专业论坛网址集合数据统计分析类:1、数据分析论坛:/bs/2、中国商业职能网络:/3、数据挖掘研究院:/4、调研在线:/5、SPSS视频教程:/programs/view/ulVnK_LMu2c/管理及销售类:1、世界经理人:/2、中国人力资源管理社区:/bbs/3、中国管理顾问论坛:/bbs/4、管理先锋论坛:/5、中华领导力论坛:/6、中国营销思考:(在线读书)/read/sell/zgyxsk/index.shtml7、中国快速消费品网:/fmcg/index.html8、栖息谷论坛:/9、品牌营销论坛:/10、销售与市场论坛:/11、中国管理传播网:/12、中国营销传播网:/13、it经理网14、阿强营销顾问室15、北大商学院16、道中国/search/searchweb.asp17、东方经理人网18、管理理论和实践社论19、国际市场网20、品牌网21、企业文化网22、企业资源管理研究中心(AMT)网23、商界24、商务周刊25、世界经理人网26、市场经济百科27、现代营销网28、项目管理者联盟29、销售与市场30、亚太管理训练网31、亚太人力资源网32、营销与市销33、整合营销在线/34、中国国家企业网35、中国经理人网36、中国经营网37、中国企业联合盟38、中国时尚品牌网39、中国项目管理网40、中国总经理网41、中华企管网42、中外管理43、全球品牌网44、南方略资讯45、亚洲ecr协会网物流管理类:1、物流沙龙:/2、物流管理:/3、供应链管理论坛:/4、RFID信息网:/html/index.html5、物流书籍评论:/default.asp?cateID=56、物流人社区:/7、中国物流论坛:/bbs/index.asp8、中国物流招标论坛:/9、中国国际航贸网:/10、中国物流人论坛:/11、中华物流论坛:/12、物流设备在线:/13、西岸外贸资料吧:/bbs/14、中国物流与采购联合协会:/经济类:1、世界经济》月刊2、世纪经济报3、北京天则经济研究所4、财经杂志5、经济观察网6、经济日报网络7、新经济网8、中国经济学教育科研所9、中国经济研究中心/cn广告策划类:1、广告人&传媒人社区2、慧聪报刊资讯3、、龙媒广告资讯网4、新广告5、中国广告人网6、中华广告KA管理类:1、联商网:/2、中华零售网:/3、零售网:/4、中国零售管理咨询网:/5、零售经理人论坛:/html/bbs.html其他:1,手机小说网:/2,天堂图库:/3,病毒王国:4,中国隐士联盟:/5,中国黑客:/6,金融时报:/7,中央政府门户网:/8,商业周刊:/9,华尔街日报:/。
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斯密论坛A D A M S M I T H F O R U M诱致性技术选择、工业化与农业增长——对中国29省农业增长的实证检验刘洪李芝倩2 0 0 2年第1卷第8期总第25期南京大学商学院经济学系·长江三角洲经济社会发展研究中心·国家经济学基础人才培养基地卷首语二百多年前,亚当〃斯密的《国富论》揭示了社会财富之源和自由竞争的市场经济之魅力,推动了人类经济思想的进步。
而今,中国走向社会主义市场经济和实现伟大复兴需要理论创新和思想进步。
南京大学商学院经济学系发起成立斯密论坛(Smithian Forum),由南京大学经济学科国家经济学基础人才培养基地和南京大学长江三角洲经济社会发展研究中心共同主办。
论坛宗旨是研讨中国改革与发展理论与实践问题,并为中国改革与发展贡献一份力量。
其研究成果是《斯密论坛》系列论文。
该论坛致力于活跃学术气氛、增进学术交流,为提高学生学术研究能力创造良好的环境。
论坛主要面向南京大学研究生与本科生,同时为保证论坛的开放性,热诚欢迎校内外的专家、老师、同学参与。
上述范围内的参与者只要提交一份正式的论文(发表或未发表均可),即可进入论坛,发表自己的观点。
诱致性技术选择、工业化与农业增长*——对中国29省农业增长的实证检验:1980—2000刘洪李芝倩南京大学商学院,210093,suanbao@内容摘要:对我国29个省份1980和2000年的农业单位土地产出和单位劳动产出的比较表明:20年中各省之间农业要素生产率差距在不断增大,尤其是发达省份和欠发达省份之间。
我国人多地少的资源禀赋状况决定了这种差距主要来源于土地和化肥产出率的不同,而与机械、劳动等要素的生产效率几乎无关。
工业化则是另外一个因素,它从农业投入品、产品市场需求以及其它诸多方面影响着农业发展的长期路径和增长水平,并加大了各省之间的差距。
因此,我国农业合理的现代化发展道路应该是走“土地节约型”的道路,即依靠化学和生物技术,而非“机械现代化”。
关键词:要素生产率、诱致性技术、工业化、农业增长一、导论尽管占据主流、影响至深的三大发展理论:“增长阶段论”(罗斯托,1956)、“二元经济论”(阿瑟.刘易斯,1954)和“结构主义依附论”(保罗.巴兰,1952)一直把农业部门看作是经济增长中的“附属部门”,忽视了农业增长过程本身。
但是,现代经济发展理论的注意力已经从“惟工业化论”转向关注农业生产率提高对经济总量发展过程的重要性,从静态的农业技术和产品需求转向关注农业剩余的获得和保持及动态的技术变革。
因此,一个新的共识正在形成:农业增长对工业化和一般经济增长即使不是前提条件,也是至关重要,必须对农业增长过程本身给予更多的重视。
这一观点由舒尔茨提出,经过速水次佑郎和拉坦的发展,已逐步获得大多数人的认同。
本文即是在这一方面的尝试,旨在考察1978年农村改革之后的我国农业20年的增长过程。
通过对全国29个不同省市的农业生产率按照每个劳动者的粮食产量和*本文是南京大学斯密论坛研究基金第一期招标课题研究成果,得到了南京大学长江三角洲经济社会发展研究中心的资助,刘志彪教授、郑江淮博士、杨德才博士对本文提出了修改意见,高峰给予了切实的帮助,在此一并感谢。
把1980年以后成立的海南省归于广东省,重庆市归于四川省,不包括港、澳、台地区。
每公顷土地的粮食产量进行比较分析,可以发现增长路径的一般特征,揭示我国农业增长的源泉,并且可以探寻适合我国资源条件的农业现代化的道路。
我们研究发现:我国各省之间农业要素生产率存在着较大的差异。
人多地少的资源禀赋特征决定了土地是制约农业长期增长的关键因素。
因而,决定省际生产率差异的主要因素从投入要素的角度看是土地和化肥,而非劳动和机械。
随着生物革命、技术进步、人力资本以及工业化、城市化等因素的变化,这种省际差距逐步扩大。
但是,资源禀赋对农业发展的影响依然是最主要的,它诱导着我国农业生产技术的选择,并且决定了我国大部分省份的农业发展轨迹具有趋同性和相似性。
此外,所谓“机械现代化”的农业发展道路并不适合我国的基本国情,合理的政策建议应该是化学技术和新生物技术的使用,尤其是对化肥投入具有更高反应能力的新作物品种;而且,在我国,无论是发达省份还是欠发达省份,都不存在规模经济,绝大部分地区处于规模经济递减的状态。
因此,各地区在农业发展技术和生物品种的选择上,应该根据本地区的资源状况合理选择,而不能一概而论。
全文大致可以分为这样几个部分:第二部分对已有的文献进行综述,阐述本文研究的出发点及意义;第三部分阐述全文的理论框架,并建立相应的计量模型;第四部分通过我国29省两个时点(1980年和2000年)的截面数据的比较,统计性地描述了各省农业要素生产率的差异;第五部分的实证检验,揭示了各省农业增长差异的源泉;第六部分是对全文的总结及几点简单的结论。
二、文献综述不少学者对中国农业增长进行了大量的研究,一般是从制度和技术两个角度进行解释。
在制度研究方面,主要集中在测定以家庭联产承包责任制为主的制度创新对农业生产的贡献(McMillan,Whalley,and Zhu,1989;林毅夫,1992)。
这些研究认为:改革以后,农业生产率的提高大部分源于制度创新。
农业技术创新是农业增长的另一源泉。
黄季焜和Rozelle(1998)指出技术进步在改革初期至少同制度创新同等重要,而且从80年代中期以来,技术进步已经成为经济增长的主要动力。
他们的结论是:在改革初期,制度创新是农业生产增长的一个重要来源,然而技术进步更为重要。
而且由于制度创新对生产的贡献只是一次性的,因而改革之后几乎所有的农业增长均来自于技术进步。
除此之外,还有其他一些因素也会对经济和农业增长产生重要影响。
首先是市场和价格政策,不同生产部门产品之间相对价格的变动不但能够促进了各部门经济对资源的竞争,也会改善地区间的资源分配和流动。
其次是政府在农业基础设施上的投资,如建立排灌设施等。
其他学者(牛若峰,1993;顾焕章等,1999;李子奈,2000)测算了各要素在农业增长中的贡献,他们的结论与本文相似,即土地和化肥的产出贡献最大。
但是他们并没有解释产生这种现象的原因。
对于经济增长和粮食生产的地区差异研究,林毅夫(1998)、王绍光(1999)等认为改革之后各地区之间的经济增长的差距逐步拉大;蔡昉等(2000)、沈坤荣(2002)则研究了各地区之间经济增长的“俱乐部”趋同性;黄爱军(1995)观察到中国粮食生产的区域变动格局具有“南方地区粮食增长中心逐渐西进”和“全国粮食增长中心逐渐北上”的趋势;国家计委农经司和国家统计局农调总队(1996)报告了中国粮食余缺分布;伍山林(2000)对全国粮食生产的区域特征分布及其变动原因进行了有益的分析。
以上的研究大多集中在农业生产增长对国民经济总发展的意义和作用上,很少考虑农业发展过程本身,并没有探讨农业生产和资源利用内在的作用机制。
对地区差异的研究虽然考察了粮食生产的区域优势、农业产业结构及资源报酬率、种粮规模及规模效益、粮食生产与农业中其他各行业的比较优势等诸多因素,但也存在如下问题:首先,他们主要考察全国大区农业的发展,并没有考察省际差别,分析结果和政策建议可能产生误导;其次,缺乏统一的理论体系;最后,他们的解释大多停留在假说的层次上,或者仅仅是描述性统计分析,很少建立计量模型并进行严格的实证检验。
本文则主要运用了速水次佑郎和拉坦(2000)提出的诱致性技术——制度创新理论对全国各省的农业增长进行分析。
林毅夫(1992)曾经运用该模型解释了要素禀赋、产品需求以及新品种开发引起的收入分配的变化,但是他的研究仅仅是针对湖南五县的样本,并没有进行全国范围之内的分析。
所谓诱致性,是指由于要素相对价格或者产品需求变化所带来的非均衡而引起技术变革和创新。
该理论反映了资源禀赋、文化禀赋、技术与制度在农业增长中的一般均衡关系,可以用来解释发展中国家和发达国家农业增长的一般路径,对于发展中国家的农业发展政策的制定具有现实的指导作用。
而且,我们对中国农业增长的研究也可以检验该理论在我国的适用性,具有较强的理论意义。
三、理论概述及模型因为一般认为制度对增长的影响是一次性的,而我们主要是考察中国农业增长的长期路径,因此把制度作为背景变量,不考虑制度变迁对农业生产的影响。
使用的数据也取于1978年之后,这些数据已经包含了家庭联产承包责任制对农业增长的影响。
主要考察劳动、土地、化肥、机械等投入要素对农业增长的贡献。
土地和劳动是农业投入的基本要素。
土地不是指单纯的自然要素,它应该包括对土地长期投资(如建设灌溉系统、施肥等)所累积的内在价值。
劳动在这里倾向于人力资本的含义,它们的相对禀赋和积累状态将会决定农业发展的实际模式。
农业的特点就是土地对生产的约束比经济中其他部门强烈得多。
农业增长可以被看作是消除由于无弹性的土地和劳动供给对生产施加的约束。
而且,土地和劳动的相对稀缺性会诱导新的更具生产效率的节约劳动或节约土地的技术变革。
技术变革是农业发展的内生变量(汉斯.宾斯旺格,1974),可以促进经济中相对丰富要素对相对稀缺要素的替代。
一个国家或者地区要想获得农业生产率和产出迅速增长的能力,取决于在各种技术途径中进行选择。
如果不能选择一条可以有效消除资源禀赋制约的途径,就会抑制农业发展和经济发展的进程。
因而技术变革是对资源禀赋变化和需求增长的一种动态反应,它主要表现在两个方面:生物化学技术和机械技术。
生物和化学技术的进步可以提高单位土地面积的作物产量或是单位饲料和单位存栏的牲畜产量。
在作物生产中,这些进步表现在:(一)开发土地和水资源,为作物生长提供良好的环境;(二)通过增加植物营养中的有机物和无机物的来源改变土壤的环境,以促进植物的生长,并运用生物和化学手段保护作物免遭病虫害;(三)选择和培育生物上有效率的作物品种,使其特别适用于那些可以人为控制的环境因素。
在人口密度和土地供给缺乏弹性的国家,生物品种对更高的施肥水平缺少反应严重制约着农业产量的增长。
肥料对于农业的增长还取决于作物品种对施肥的反应。
因此,要解除土地供给缺乏弹性对增长的制约,应该培育对化肥具有反应的农作物品种。
同样,在一种以劳动力相对稀缺为特征的经济中,土地对劳动的替代,可以通过改进农用工具和机械而实现。
机械设备的发展可以增加每个劳动者所能经营的土地面积,从而使人均产量上升。
因此,根据希克斯(1932)对生产技术的分类标准,可以把机械技术称为“劳动节约型”,生物和化学技术看成是“土地节约型”。
当然,这不是绝对如此。
机械技术的开发可以是节约土地型,而生物技术的开发也可以是节约劳动型。
尽管在气候、技术和产品等方面存在着巨大的差别,土地和劳动生产率的主要差别还与工业品投入水平的不同有关,因为工业投入品可以消除基本要素的无弹性供给所带来的制约。