Thermoelectric properties of nanostructured FeSi2 prepared by field-activated

附件6作者姓名：卢滇楠论文题目：温敏型高分子辅助蛋白质体外折叠的实验和分子模拟研究作者简介：卢滇楠，男，1978年4月出生, 2000年9月师从清华大学化工系生物化工研究所刘铮教授，从事蛋白质体外折叠的分子模拟和实验研究，于2006年1月获博士学位。

博士论文成果以系列论文形式集中发表在相关研究领域的权威刊物上。

截至2007年发表与博士论文相关学术论文21篇，其中第一作者SCI论文9篇（有4篇IF>3），累计他引20次（SCI检索），EI收录论文14篇（含双收），国内专利1项。

中文摘要引言蛋白质体外折叠是重组蛋白质药物生产的关键技术，也是现代生物化工学科的前沿领域之一，大肠杆菌是重要的重组蛋白质宿主体系，截止2005年FDA批准的64种重组蛋白药物中有26种采用大肠杆菌作为宿主体系，目前正在研发中的4000多种蛋白质药物中有90%采用大肠杆菌为宿主表达体系。

但由于大肠杆菌表达系统缺乏后修饰体系使得其生产的目标蛋白质多以无生物学活性的聚集体——包涵体的形式存在，在后续生产过程中需要对其进行溶解，此时蛋白质呈无规伸展链状结构，然后通过调整溶液组成诱导蛋白质发生折叠形成具有预期生物学活性的高级结构，这个过程就称之为蛋白质折叠或者复性，由于该过程是在细胞外进行的，又称之为蛋白质体外折叠技术。

蛋白质体外折叠技术要解决的关键问题是避免蛋白质的错误折叠以及形成蛋白质聚集体。

目前本领域的研究以具体技术和产品折叠工艺居多，折叠过程研究方面则多依赖宏观的结构和性质分析如各类光谱学和生物活性测定等，在研究方法上存在折叠理论、分子模拟与实验研究结合不够的问题，这些都不利于折叠技术的发展和应用。

本研究以发展蛋白质新型体外折叠技术为目标，借鉴蛋白质体内折叠的分子伴侣机制，提出以智能高分子作为人工分子伴侣促进蛋白质折叠的新思路，即通过调控高分子与蛋白质分子的相互作用，1）诱导伸展态的变性蛋白质塌缩形成疏水核心以抑制蛋白质分子间疏水作用所导致的聚集，2）与折叠中间态形成多种可逆解离复合物，丰富蛋白质折叠的途径以提高折叠收率。

纳米金属颗粒物原位催化英文In-situ Catalysis of Nanometal Particles.Nanometal particles, with their unique physicochemical properties, have emerged as promising catalysts in various chemical reactions. The concept of in-situ catalysis, which involves the utilization of these nanoparticles directly at the reaction site, offers significant advantages such as improved activity, selectivity, and efficiency. In this article, we delve into the principles, applications, and challenges associated with in-situ catalysis using nanometal particles.Principles of In-situ Catalysis.In-situ catalysis refers to the use of catalysts that are generated or activated directly within the reaction mixture, rather than being added as preformed entities. In the context of nanometal particles, this approach allowsfor a more intimate interaction between the catalyst andthe reactants, leading to enhanced catalytic activity. The small size of these nanoparticles ensures a high surface-to-volume ratio, which in turn results in a greater numberof active sites available for catalysis.The catalytic activity of nanometal particles isfurther enhanced by their unique electronic and structural properties. The quantum size effects observed in nanoparticles lead to changes in their electronic structure, which can significantly alter their catalytic behavior. Additionally, the high surface energy of nanoparticles promotes their stability and prevents sintering, even at elevated temperatures, maintaining their catalytic activity over extended periods.Applications of In-situ Catalysis.The applications of in-situ catalysis using nanometal particles are diverse and span across various fields of chemistry and engineering. Some of the key applications include:1. Organic Synthesis: Nanometal particles, especially those of platinum, palladium, and gold, have found widespread use in organic synthesis reactions such as hydrogenation, carbon-carbon bond formation, and oxidation reactions. Their use in in-situ catalysis allows for more efficient and selective transformations.2. Fuel Cells: Nanometal particles, particularly those of platinum and palladium, are key components in the electrodes of fuel cells. Their in-situ catalysis promotes the efficient oxidation of fuels such as hydrogen, leading to improved fuel cell performance.3. Photocatalysis: The combination of nanometal particles with photocatalysts such as titanium dioxide offers a powerful tool for solar-driven reactions. The in-situ generation of reactive species at the interface of these materials enhances photocatalytic activity and selectivity.Challenges and Future Directions.While the potential of in-situ catalysis using nanometal particles is immense, there are several challenges that need to be addressed. One of the key challenges is the stability of these nanoparticles under reaction conditions. The aggregation and sintering of nanoparticles can lead to a decrease in their catalytic activity. To address this, strategies such as stabilization by ligands or supports, and the use of bimetallic or core-shell structures have been explored.Another challenge lies in the scale-up of these processes for industrial applications. While laboratory-scale experiments often demonstrate promising results, translating these findings to large-scale operations can be challenging due to factors such as mass transport limitations and heat management.Future research in in-situ catalysis with nanometal particles could focus on developing more robust and stable catalyst systems. The exploration of new nanomaterials with enhanced catalytic properties, as well as the optimization of reaction conditions and reactor designs, are likely tobe key areas of interest. Additionally, the integration ofin-situ catalysis with other technologies such as microfluidics and nanoreactors could lead to more efficient and sustainable catalytic processes.In conclusion, the field of in-situ catalysis using nanometal particles offers significant potential for enhancing the efficiency and selectivity of chemical reactions. While there are still challenges to be addressed, the ongoing research in this area is likely to lead to transformative advancements in catalysis and beyond.。

2016年2月 CIESC Journal ·627·February 2016第67卷 第2期 化 工 学 报 V ol.67 No.2阳极氧化二氧化钛纳米管涂层地热水腐蚀和沉积特性张帆1，刘明言1,2，徐杨书函1（1天津大学化工学院，天津化学化工协同创新中心（天津），天津 300072；2化学工程联合国家重点实验室（天津大学），天津 300072）摘要：拟采用金属二次阳极氧化等表面工程技术抑制地热水的腐蚀和结垢现象。

在纯钛和钛合金（Ti-6Al-4V ）板基底上采用二次阳极氧化法制备了二氧化钛微纳米管阵列涂层，探讨了制备工艺参数对涂层结构的影响，并进一步采用浸渍法对涂层进行了超疏水化处理。

通过场发射环境扫描电镜表征了涂层的微观结构形貌。

应用视频光学接触角测量仪检测了涂层表面的静态接触角，估算了表面自由能。

对涂层的粗糙度也进行了测量。

采用静态浸渍法评估了涂层的防垢性能。

采用电化学线性极化曲线法研究了涂层在地热水中的耐腐蚀效果。

结果表明，在钛及钛合金基底上，采用二次阳极氧化和浸渍工艺，可以制得具有规整二氧化钛微纳米管阵列结构和较低表面能的功能涂层；该涂层与基底相比，在地热水中的耐腐蚀性能得以提高；在碳酸钙饱和溶液中的污垢沉积速率降低约15%。

同时，涂层与基底有较好的结合性能，疏水涂层经历多次胶带剥离和砂纸磨损实验后，依然保持着较高的疏水性。

关键词：阳极氧化；涂层；腐蚀；结垢；表面；疏水 DOI ：10.11949/j.issn.0438-1157.20151064中图分类号：TQ 050.9 文献标志码：A 文章编号：0438—1157（2016）02—0627—14Corrosion and deposition properties on anodization coatings of titaniumdioxide nanotubes in geothermal waterZHANG Fan 1, LIU Mingyan 1,2, XU Yangshuhan 1（1Collaborative Innovation Center of Chemical Science and Engineering (Tianjin ), School of Chemical Engineering and Technology , Tianjin University , Tianjin 300072, China ; 2State Key Laboratory of Chemical Engineering (Tianjin University ), Tianjin 300072, China ）Abstract: In this paper, surface engineering technique of two-step anodization was used to solve the problems of corrosion and fouling in the geothermal water. TiO 2 nanotube layers were prepared on the substrates of pure titanium and its alloy (Ti-6Al-4V), and factors affecting layer structure were explored. Hydrophobization was further applied on the surface of TiO 2 coatings by immersion method. Microstructures of TiO 2 nanotubes were characterized by SEM. Static contact angle was obtained on the coatings via optical contact angle measuring device, and surface free energy was calculated. Roughness of the coatings was measured. Fouling property of coatings was investigated by static immersion experiments in CaCO 3 fouling solution. Corrosion property of coatings in geothermal water was investigated by potentiodynamic polarization curve. Well-aligned array of TiO 2 nanotubes and micro- and nano-scale coatings with low surface free energy were obtained on substrates of pure titanium and its alloy under optimal conditions of two-step anodization and immersion techniques. The TiO 22015-07-06收到初稿，2015-09-09收到修改稿。

RESEARCH PAPERLaser synthesis and size tailor of carbon quantum dotsShengliang Hu •Jun Liu •Jinlong Yang •Yanzhong Wang •Shirui CaoReceived:1July 2011/Accepted:5November 2011/Published online:17November 2011ÓSpringer Science+Business Media B.V.2011Abstract Carbon quantum dots (C-dots)with aver-age sizes of about 3,8,and 13nm were synthesized by laser irradiation of graphite flakes in polymer solution.The obtained C-dots display size and excitation wavelength dependent photoluminescence behavior.The size control of C-dots can be realized by tuning laser pulse width.The original reason could be the effects of laser pulse width on the conditions of nucleation and growth of pared with short-pulse-width laser,the long-pulse-width laser would be better fitted to the size and morphology control of nanostructures in the different material systems.Keywords Carbon nanoparticle ÁLaser ablation in liquid ÁSize control ÁPhotoluminescence ÁThermodynamic theoryIntroductionNanomaterials exhibit special properties or behavior that they would not do if they were not so small (Hodes 2007).Nanometer-size-determined properties are often called since many properties of materials undergo qualitative,often sudden,changes below a certain size scale (Hodes 2007;Link and El-Sayed 2003).On the basis of the differences of material chemical composition,such threshold size can vary from a nanometer or even less to the micrometer range.Even when the size reduces below such certain size scale,the physical properties of a material of a particular fixed chemical composition changes con-tinuously with change in crystal size due to size quantization effect (Hodes 2007;Link and El-Sayed 2003;Chen et al.2006).Therefore,the size control or tailor becomes a decisive factor in nanomaterial development.However,it is not easy to tailor the size of nanomaterials that we need.A great deal of effort has been put into this task,but all the developed methods follow as the basic mechanism:size control of nucleation and growth (and aggregation)limitation of nuclei (Li et al.2008;Park et al.2011;Wang et al.2010;Oh et al.2010).Electronic supplementary material The online version of this article (doi:10.1007/s11051-011-0638-y )containssupplementary material,which is available to authorized users.S.Hu (&)ÁJ.LiuKey Laboratory of Instrumentation Science &Dynamic Measurement (North University of China),Ministryof Education,Science and Technology on Electronic Test and Measurement Laboratory,Taiyuan 030051,People’s Republic of China e-mail:hsliang@S.Hu ÁY.Wang ÁS.CaoSchool of Materials Science and Engineering,North University of China,Taiyuan 030051,People’s Republic of ChinaJ.YangState Key Laboratory of New Ceramics and Fine Processing,Tsinghua University,Beijing 100084,People’s Republic of ChinaJ Nanopart Res (2011)13:7247–7252DOI 10.1007/s11051-011-0638-yLaser ablation is an efficient physical method for nanomaterial synthesis through laser irradiation of a solid target in liquid(Mafune´et al.2000;Amendola and Meneghetti2007;Khan et al.2009;Liu et al. 2010).Although this technique has many advantages (such as simplicity and versatility),and can prepare a variety of nanostructures(Khan et al.2009;Liu et al. 2010;Singh et al.2010;Hu et al.2009a,b,2011),there is still an open question of how to tailor the product size from laser ablation by the simple regulation of laser parameters.Previously,many efforts made focused on the liquid medium adjustments for size reduction and novel nanostructures(Mafune´et al. 2000;Khan et al.2009;Liu et al.2010;Singh et al. 2010).A few of researchers even found the effects of laser power on the size,but no one revealed the origin of size control under laser ablation in liquid(LAL) (Mafune´et al.2000;Amendola and Meneghetti2007). Herein,taking laser synthesis of carbon quantum dots (C-dots)as an example,we showed a facile method to attain size tailor by the regulation of laser parameters. With the aid of thermodynamic theory,the possible origin of size control upon LAL was also given in this report.C-dots constitute a fascinating class of recently discovered nanocarbons that consist of discrete and quasispherical nanoparticles with small sizes(Baker and Baker2010).In addition to their well-known biocompatibility,which could be a more suitable alternative for in vivo biolabeling(Baker and Baker 2010;Lu et al.2009;Hu et al.2009a,b),C-dots also exhibit many interesting properties,such as photo-induced electron transfer,redox and‘two-photon excitation absorption(Baker and Baker2010;Wang et al.2009;Li et al.2010).Therefore,such C-dots have attracted intensive research.Various synthetic routes have been developed to produce C-dots,but can be generally classified into two main groups: top–down and bottom–up methods(Baker and Baker2010).Our reported laser synthesis belongs to a top–down approach.We utilize a laser with a long-pulse width,that is,a millisecond-pulsed laser, to prepare C-dots.Such a laser is commonly used for welding but seldom for the synthesis of nanom-aterials.Due to its long-pulse width,the laser-induced physical processes are expected to be easily controlled by the regulation of pulse width.Thus, this is helpful to our realization of size tailor of nanomaterials upon LAL.ExperimentalGraphite powders with an average size of2l m were purchased from Qindao Graphite Co.Ltd.A Nd:YAG pulsed laser with a wavelength of1.064l m and power density of59106W/cm2was used to irradiate graphiteflakes dispersed in the poly(ethylene glycol) (PEG1500N)solution.The laser pulse width used in the experiment can be tuned from0.2to10ms under the same laser power density,which can be measured by a laser power meter(LEM2020).Ultrasound was employed during the laser irradiation to expedite the movement of graphite powders.After4-h irradiation a homogeneous black suspension was obtained which was centrifuged(5,000rpm)and separated into a black carbon precipitate and a colorful supernatant. The supernatant was used for further analysis.The photoluminescence(PL)spectra were measured on a Hitachi F4500fluorescence spectrophotometer.FEI Tecnai G2F20field-emission-gun transmission elec-tron microscopy(TEM)was employed to analyze the structure of C-dots.Results and discussionThree samples were prepared by employing the laser pulse widths of0.3,0.9,and1.5ms and three same colorful supernatants(Fig.1a shows a typical direct photograph)were obtained after centrifugation.To easily explain,they were named as samples A,B,and C in turn,which are corresponded to the samples produced from the laser pulse widths of0.3,0.9,and 1.5ms,respectively.Under irradiation with a365nm ultraviolet(UV)lamp,all the samples show blue color and one of their direct photographs is given in Fig.1b. PL spectra of three samples were measured at the same excitation wavelength(430nm)and the results were shown in Fig.1c.It can be seen that the differences of PL spectra between samples A,B,and C are not large. Only about10nm changes between their maximum peaks are observed.Moreover,the light emissions of three samples depend on the excitation wavelength. Figure1d shows the typical excitation wavelength dependent PL behavior of sample A.It can be seen that the peak positions of PL spectra are tunable with excitation wavelengths and the full width at half maximum(FWHM)of luminescent peak reduces with the decrease of excitation energy.Although samples A,B,and C have the same color and PL behavior,their fluorescence quantum yields (FQYs)that can be calculated according with the references (Lakowicz 1999;Liu et al.2007;Xu et al.2004)are obviously different (See Supporting Infor-mation).The FQY of sample A (12.2%)is above ten times higher than that of sample C (1.2%)while the FQY of sample B is 6.2%.To get the reasons why the FQYs of three samples were different,we studied their size distributions and microstructures according to high-resolution TEM (HRTEM)characterizations and the results were given in Fig.2.It can be seen from Fig.2d,e and f that the maximum values of the fitted Gaussian peak for the sizes of samples A,B,and C are 3.2,8.1,and 13.4nm,respectively,suggesting the sizes of C-dots increase as laser pulse width increases.On the other hand,the microstructures of three samples were investigated to disclose the differences of both the sizes and FQYs.HRTEM images indicate that carbon nanoparticles in sample A are singlecrystalline grain and have some defects while carbon nanoparticles in sample B and C are composed of two and more crystalline grains.The typical interfaces between nanometer grains have been marked by red arrows in Fig.2b,c,suggesting that a large nanocrys-tal is formed by coagulation of several nuclei.Since the FQYs could be determined by the sizes,it is important to understand the effect of laser pulse width on the size of C-dots.Accordingly,we will discuss the nucleation and growth process under laser irradiation with the aid of thermodynamic theory to disclose the formation of C-dots with the different sizes.The interaction between the laser beams and the graphite flakes produces an instant local high-temper-ature and high-pressure vapor/plasma plume at the interface of the graphite flake and the surrounding liquid medium (Fig.3-Step 1)(Bai et al.2010;Yang 2007).Due to liquid confinement,a bubble is formed from laser-induced plume at the laser focus,andrapidly expands up to a maximum radius (GregorcˇicˇFig.1a A typical photograph of the supernatant obtained by centrifugation;b the direct photograph of the obtained supernatant irradiated by 365nm UV lamp;c emission spectra of samples A,B,C obtained at 430nm wavelength excitation;d PL spectra of sample A obtained by the different wavelengthexcitationFig.2a –c are typical HRTEM images of sample A,B,and C,respectively;d –f correspond to the size distributions of sample A,B,and Cet al.2007;Takada et al.2010;Sasaki and Takada 2010).Subsequently,after a laser pulse width finishes,the bubble starts to shrink due to the pressure of the surrounding liquid,leading to the cooling of its inner region and thus to the formation of clusters or nuclei (Fig.3-Step 2)(Takada et al.2010;Sasaki and Takada 2010;Brujan et al.2002).Since the interaction time between the laser beams and the graphite flakes is determined by the laser pulse width,the bubbles containing the different cluster densities can be formed under the same laser beam energy when thelaser pulse width is changed.Accordingly,two cases can be obtained when the short (C1)and long (C2)laser pulse widths are employed.According to our thermodynamic calculations (see Supporting information),both the critical radius and the nucleation barrier reduce as the supersaturation and the temperature increase (see Fig.4).Specially,they rapidly decrease with the increase of the super-saturation when the supersaturation is below 4.It can be seen from Fig.5that the nucleation time decreases as the supersaturation and temperature increase while the nucleation rate increases with their increase.Accordingly,our thermodynamic calculations suggest that the higher supersaturation or cluster density in the bubble is beneficial for nucleation.The increase of nucleation rate results in the reduction of the distance between individual nuclei.In addition,the smaller the nuclei,the easier the movement is.Therefore,the formed nuclei could be contacted with one another with the further shrink of the bubble.Thus,the coagulation takes place and then leads to the formation of the larger nuclei.However,the coalescence can not have enough time to complete possibly due to rapid cooling resulted from the bubble collapse.Certainly,the nuclei could also become larger bygrowth.Fig.3Schematic of the mechanism of size control of C-dots obtained upon LAL.C1and C2correspond to the cases at the short and long laser pulse widths,respectivelyFig.4a The dependence of the critical radius and nucleation barrier on the supersaturation at the given temperatures;b the relationship curve between the nucleation energy barrier and the supersaturation at the giventemperatures Fig.5a The dependence of the nucleation time on the supersaturation under the various temperatures;b the relation-ship curve between the nucleation rate and the supersaturation under the various temperaturesBased on the Wilson-Frenkel growth law (Hu et al.2010),we obtained the relationship curves between the growth velocity of the nuclei and the supersaturation at the given temperatures (Fig.6).The results indicate that the growth velocity slowly increases when the supersaturation is beyond 3,and it decreases quickly as the temperature decreases,i.e.,the high supersatura-tion and low temperature are not in favor of the growth of the nuclei.This suggests that the nucleation is easier than the growth in the bubble with the high density.Thereby,the nuclei become large by coagulation when the high cluster density is created in the bubble.Since the cluster density in the bubble is determined by the interaction time between pulsed laser and materials,the different sizes of C-dots can be generated when the laser pulse width is changed.After the collapse of the bubbles,the surface reaction takesplace when nano-particles touch with polymer (PEG 1500N ).As a conse-quence carbon nanoparticles with surface passivation (Hu et al.2009a ,b ),i.e.,C-dots,are produced (Fig.3-Step 3).The other role of surface passivation playedprevents nanoparticles from aggregating (Mafune´et al.2000;Singh et al.2010).Since the surface energy traps are generally believed as the origin of the light emission from C-dots (Sun et al.2006),having good surface passivation is favorable to the FQY improvement.However,whether the surface passiv-ation with polymer is good or bad generally depends on the specific surface of carbon nanoparticles.This is why the FQYs of C-dots depend on their sizes.Previously,nanoparticles or nanostructures are generally fabricated by using short-pulse-width laser,for instance,a nanosecond pulsed laser with a pulse width of several nanoseconds and power density of 108–1010W/cm 2(Liu et al.2010;Yang 2007).However,it could be not suited to prepare ultrasmall nanostructures and tailor the product size.On the onehand,LAL method,indeed,does not allow good control of reaction parameters compared with chem-ical reduction methods and so it is hard to obtain the predetermined sizes upon LAL (Amendola and Mene-ghetti 2007).On the other hand,the high energy flux is provided in a short time and then the high density is generated in the laser-induced bubble.Lots of nuclei are formed simultaneously and then coagulated with the shrink of the bubble.Therefore,the large nano-structures are generally obtained using the short-pulse-width laser with the high power density (Liu et al.2010;Singh et al.2010;Yang 2007).Although the moderate regulation for laser beam energy can be carried out by laser itself,a smaller bubble is generated from lower laser power density and then the too quick cooling takes place due to the short interaction time between laser beams and target,suggesting hard nucleation and growth.Thus,the synthesis efficiencies of nanomaterials could be low.However,when a long-pulse-width laser is employed,the laser-induced conditions generated in the bubble can be tailored by the changes of laser pulse width and then the size control could be realized.Moreover,the high synthe-sis efficiency could be still obtained in the experiment.Therefore,based on above consideration,the long-pulse-width laser with the lower power density would be better fitted for the preparation of ultrasmall nanostructures and the control of size distribution.ConclusionOne-step synthesis of C-dots was performed by laser irradiation of graphite flakes in polymer solution.The obtained C-dots exhibit the excitation wavelength dependent PL behavior.The PL efficiencies of C-dots depend on their size distribution.Their size distribu-tion can be controlled by regulating pulse width of the millisecond-pulsed laser with the lower power density.Tuning laser pulse width could change the laser-induced conditions in the bubble and then lead to the changes of the nucleation and growth process and produce the different size distribution.Therefore,the long-pulse-width laser could be better fitted to various nanostructure synthesis and size tailor,and would be applied in different material systems.Acknowledgments This study was financially supported by the National Natural Science Foundation of China(Nos.Fig.6The relationship curve between the growth velocity and the supersaturation at the given temperatures50902126,51172214),Shanxi Province Science Foundation for Youths(No.2009021027),and Program for the Top Young Academic Leaders of Higher Learning Institutions of Shanxi. ReferencesAmendola V,Meneghetti M(2007)Controlled size manipula-tion of free gold nanoparticles by laser irradiation and their facile bioconjugation.J Mater Chem17:4705–4710Bai P,Hu S,Zhang T,Sun J,Cao S(2010)Effect of laser pulse parameters on the size andfluorescence of nanodiamonds formed upon pulsed-laser irradiation.Mater Res Bull 45:826–829Baker SN,Baker GA(2010)Luminescent carbon nanodots: emergent nanolights.Angew Chem Int Ed49:6726–6744 Brujan EA,Keen GS,Vogel A,Blake JR(2002)Thefinal stage of the collapse of a cavitation bubble close to a rigid boundary.Phys Fluids14:85–92Chen CQ,Shi Y,Zhang YS,Zhu J,Yan YJ(2006)Size dependence of Young’s modulus in ZnO nanowires.Phys Rev Lett96:075505(1–4)GregorcˇicˇP,Petkovsˇek R,Mozˇina J(2007)Investigation of a cavitation bubble between a rigid boundary and a free surface.J Appl Phys102:094904(1–8)Hodes G(2007)When small is different:some recent advances in concepts and applications of nanoscale phenomena.Adv Mater19:639–655Hu S,Bai P,Tian F,Cao S,Sun J(2009a)Hydrophilic carbon onions synthesized by millisecond pulsed laser irradiation.Carbon47:876–883Hu S,Niu KY,Sun J,Yang J,Zhao NQ,Du XW(2009b)One-step synthesis offluorescent carbon nanoparticles by laser irradiation.J Mater Chem19:484–488Hu S,Lu X,Yang J,Liu W,Dong Y,Cao S(2010)Prediction of formation of cubic boron nitride nanowires inside silicon nanotubes.J Phys Chem C114:19941–19945Hu S,Yang J,Liu W,Dong Y,Cao S(2011)Carbon nanocage bubbles produced by pulsed-laser ablation of carbon in water.Carbon49:1505–1507Khan SZ,Yuan Y,Abdolvand A,Schmidt M,Crouse P,Li L, Liu Z,Sharp M,Watkins KG(2009)Generation and characterization of NiO nanoparticles by continuous wave fiber laser ablation in liquid.J Nanopart Res11:1421–1427 Lakowicz RZ(1999)Principles offluorescence spectroscopy, 2nd edn.Klumer Academic/Plenum Publishers,New York Li Z,Tan B,Allix M,Cooper AI,Rosseinsky MJ(2008)Direct coprecipitation route to monodisperse dual-functionalized magnetic iron oxide nanocrystals without size selection.Small4:231–239Li H,He X,Kang Z,Huang H,Liu Y,Liu J,Lian S,Tsang CHA, Yang X,Lee S-T(2010)Water-solublefluorescent carbonquantum dots and photocatalyst design.Angew Chem Int Ed49:4430–4434Link S,El-Sayed MA(2003)Optical properties and ultrafast dynamics of metallic nanocrystals.Annu Rev Phys Chem 54:331–366Liu H,Ye T,Mao C(2007)Fluorescent carbon nanoparticles derived from candle soot.Angew Chem Int Ed46: 6473–6475Liu P,Cui H,Wang CX,Yang GW(2010)From nanocrystal synthesis to functional nanostructure fabrication:laser ablation in liquid.Phys Chem Chem Phys12:3942–3952 Lu J,Yang J-X,Wang J,Lim A,Wang S,Loh KP(2009)One-pot synthesis offluorescent carbon nanoribbons,nanopar-ticles,and graphene by the exfoliation of graphite in ionic liquid.ACS Nano3:2367–2375Mafune´F,Kohno J-Y,Takeda Y,Kondow T,Sawabe H(2000) Formation and size control of silver nanoparticles by laser ablation in aqueous solution.J Phys Chem B104:9111–9117 Oh W-K,Yoon H,Jiang J(2010)Size control of magnetic carbon nanoparticles for drug delivery.Biomaterials31:1342–1348 Park KH,Im SH,Park OO(2011)The size control of silver nanocrystals with different polyols and its application to low-reflection coating materials.Nanotechnology22:045602 (1–6)Sasaki K,Takada N(2010)Liquid-phase laser ablation.Pure Appl Chem82:1317–1327Singh SC,Mishra SK,Srivastava RK,Gopal R(2010)Optical properties of selenium quantum dots produced with laser irradiation of water suspended Se nanoparticles.J Phys Chem C114:17374–17384Sun Y-P,Zhou B,Lin Y,Wang W,Fernando KAS,Pathak P, Meziani MJ,Harruff BA,Wang X,Wang H,Luo PG,Yang H,Kose ME,Chen B,Veca M,Xie S-Y(2006)Quantum-sized carbon dots for bright and colorful photolumines-cence.J Am Chem Soc128:7756–7757Takada N,Nakano T,Sasaki K(2010)Formation of cavitation-induced pits on target surface in liquid-phase laser ablation.Appl Phys A101:255–258Wang X,Cao L,Lu F,Meziani MJ,Li H,Qi G,Zhou B,Harruff BA,Kermarrec F,Sun Y-P(2009)Photoinduced electron transfers with carbon dots.Chem Commun25:3774–3776 Wang F,Han Y,Lim CS,Lu Y,Wang J,Xu J,Chen H,Zhang C, Hong M,Liu X(2010)Simultaneous phase and size control of up conversion nanocrystals through lanthanide doping.Nature463:1061–1064Xu X,Ray R,Gu Y,Ploehn HJ,Gearheart L,Raker K,Scrivens WA(2004)Electrophoretic analysis and purification of fluorescent single-walled carbon nanotube fragments.J Am Chem Soc126:12736–12737Yang GW(2007)Laser ablation in liquids:applications in the synthesis of nanocrystals.Prog Mater Sci52:648–698。

第49卷第12期2020年12月应用化工Applied Chemical IndustryVol.49No.12Dec.2020聚苯胺材料在CO2分离膜中的应用研究进展张清1,王永洪V(1.太原理工大学化学化工学院，山西太原030024；2,气体能源高效清洁利用山西省重点实验室，山西太原030024)摘要:主要介绍了聚苯胺的物理化学性质,纳米材料的制备方法，综述了近年来基于聚苯胺材料的混合基质膜、复合膜、共混膜的CO?分离研究进展，分析了聚苯胺的CO?促进传递机理,指出了研究中存在的问题,并对聚苯胺材料的未来研究方向进行了预测。

关键词:聚苯胺;膜;CO?分离;促进传递中图分类号:TQ028.1文献标识码:A文章编号：1671-3206(2020)12-3226-04Research progress of polyaniline materialfor CO2separation membraneZHANG Qing, WANG Yong-hong1'2(1.College of Chemistry and Chemical Engineering,Taiyuan University of Technology,Taiyuan030024,China；2.Shanxi Key Laboratory of Gas Energy Efficient and Clean Utilization,Taiyuan030024,China)Abstract:The physical and chemical properties of polyaniline and the preparation of nano-materials are mainly introduced,the research progress in C02separation of mixed matrix membranes,composite mem­branes and blend membranes based on polyaniline materials is reviewed.The mechanism of C02-promoted transfer of polyaniline was analyzed.The existing problems in the research were pointed out,and the future research direction of polyaniline materials was predicted.Key words:polyaniline；membrane；C02separation；facilitated transfer碳基化石燃料(煤、石油和天然气)等能源需求的快速增长导致全球C02排放量增加⑴,2019年底，全球燃烧化石燃料产生的CO?排放量预计高达368亿t,大量CO?排放加剧了全球温室效应⑵。

螺旋碳纳米管的制备、表征及性能张洋,范猛,文剑锋,汤怒江,钟伟,都有为(南京大学南京微结构国家实验室,南京210093)摘要:采用溶胶-凝胶结合氢气还原方法制备了Ni纳米颗粒,并用这种Ni纳米颗粒作为催化剂,通过催化裂解乙炔的方法在425e制备了螺旋度较高且呈对称生长的螺旋碳纳米管。

结果表明,本方法简单、成本低、环境友好,可大量制备高纯度螺旋碳纳米管。

场发射扫描电镜(FE-SEM)及高分辨透射电镜(H R-TEM)图片表明,通常情况下两根旋向相反的螺旋碳纳米管生长在一个催化剂颗粒上,且这种纳米螺旋呈空心管状。

X射线衍射及拉曼光谱分析表明,所得样品成分为有缺陷的石墨结构和镍多晶,未发现其他杂相。

此外,对样品的磁性及微波吸收性能进行了研究。

关键词:螺旋碳纳米管;催化生长;磁性;微波吸收特性;溶胶-凝胶;Ni纳米颗粒中图分类号:TB383文献标识码:A文章编号:1671-4776(2011)08-0494-05Synthesis,Characterization and Performance ofHelical Carbon NanotubesZhang Yang,Fan Meng,W en Jianfeng,Tang N ujiang,Zhong Wei,Du Youw ei(N anj ing N ational L abor ato ry of M icr ostr uctur es,N anj ing Univer sity,N anj ing210093,China)Abstract:The Ni nano-particles w ere generated by means of a so-l g el combined hydrogen r educ-tion m ethod.T he helical carbon nanotubes(H CNTs)w ith hig h helicity and sym metr ic structure w ere synthesized in acety lene pyroly sis at425e using the Ni nano-par ticles as the catalyst.The results show that this method is simple and environmentally friendly w ith low-cost,and is an ideal candidate fo r the mass pr oduction of H CNT s w ith hig h purity.The field-emission scanning elec-tro n micr oscope(FE-SEM)and high-resolution transm ission electron microscope(H R-TEM) im ages show that there are often tw o nanotubes w ith the ho llow tubular structure and opposite rotating directions in one cataly st nanopar ticle.The XRD and Raman results reveal that the com-posites of the as-prepared sample are gr aphite w ith defect and po lycrystalline N i w ithout im purity phase.M oreover,the m ag netism and m icrow ave absorptio n proper ties o f the as-prepared sam ple w ere investigated.Key words:helical carbon nanotube;catalytic gro w th;magnetic pro perty;micro w av e abso rption pro perty;so-l g el;Ni nano particleDOI:10.3969/j.issn.1671-4776.2011.08.003PACC:6148收稿日期:2011-04-11基金项目:国家自然科学基金资助项目(51072079)E-mail:tan gnujiang@0引言具有全新微结构的碳材料(例如螺旋碳纳米管和石墨烯等)与传统结构的碳材料相比,具有全新的物理性能,也是近年来物理学家关注的热点。

第15卷第2期2024年4月有色金属科学与工程Nonferrous Metals Science and EngineeringVol.15，No.2Apr. 2024轧制压下率、路径对NiCoCr 合金微观结构和力学性能的影响冯天a ，b ， 孔见b ， 张勇*a ，b， 赵永好b（南京理工大学，a.格莱特纳米科技研究所； b.材料科学与工程学院，南京 210094）摘要：通过开展不同轧制压下率和路径的轧制实验，制备了具有不同比例和尺寸的纳米孪晶和纳米晶结构 NiCoCr 合金。

透射电镜表征结果表明，单向轧制压下率50%样品中微观结构特征以纳米孪晶和高密度位错为主。

当压下率达到90%，由于剪切带在纳米孪晶片层结构中的开动，孪晶体积分数下降，同时剪切带内形成大量尺寸为35 nm 的纳米晶结构。

多方向轧制样品中微观结构以纳米晶结构为主，平均尺寸为27 nm ，略小于单向轧制压下率90%样品中的纳米晶尺寸。

拉伸实验结果表明：相比于轧制前固溶态粗晶合金，单向轧制压下率50%纳米孪晶镍基合金强度大幅提高，合金屈服强度和抗拉强度分别达到1 312 MPa 和1 396 MPa 。

压下率90%轧制样品屈服强度高达1 599 MPa ，变方向轧制样品屈服强度更是高达1 705 MPa 。

同时拉伸试验数据表明，晶粒细化可以有效地提高材料强度，但是材料的延伸率显著下降。

关键词：轧制；镍基合金；力学性能；纳米孪晶；晶粒细化中图分类号：TG335.12 文献标志码：AThe effects of cold rolling thickness reduction and path on the microstructure and mechanical properties of NiCoCr alloyFENG Tian a,b , KONG Jian b , ZHANG Yong *a,b , ZHAO Yonghao b（Nanjing University of Science and Technology ， a.Herbert Gleiter Institute of Nanoscience ； b. School ofMaterials Science and Engineering ， Nanjing 210094，China ）Abstract: Bulk NiCoCr alloy samples with different volume fraction of nano-twins and nano-grains were fabricated by cold rolling with various thickness reduction and strain path. Transmission electron microscopy observations indicate that the microstructure in the one-directional rolled sample with 50% thickness reduction is characterized by nano-twins and high density of dislocations. With increasing the rolling thickness reduction to 90%, the volume fraction of nano-twins decreases due to the activation of shear banding within the nano-twined lamellar area, which consequently leads to the formation of massive nano-grains with average sizes of 35 nm. The microstructure of the multi-directional rolled sample is mainly composed of nano-grains with main sizes of 27 nm, which is slightly smaller than that of one-directional rolled sample. Tensile test results show that the strength of the one-directional rolled sample with 50% thickness reduction is significantly enhanced with yield strength and ultimate tensile strength reaching 1 312 MPa and 1 396 MPa, respectively, which is much higher as compared to the coarse-grained alloy with solid solution heat treatment. The yield strength is further increased to 1 599 MPa with thickness reduction reaching 90%, and multiple-directional rolling gives rise to a higher yield strength of 1 705 MPa. Tensile收稿日期：2024-03-21；修回日期：2024-04-03基金项目：国家自然科学基金资助项目（51601091）；江苏省前沿引领技术基础研究重大项目（BK20222014）通信作者：张勇（1982—　），博士，教授，主要从事极端环境材料的设计和使役行为研究等方面的工作。