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Chinese Journal of Structural Chemistry 2007年第2期26卷 229-233页

作者： han Xiang-Yun ZHENg Qing Department of Chemical Engineering YanchengInstitute of Technology Jiangsu 224003 China

geometrical configurations of 16 substituted biphenyls were computed at the B3LYP/6-311g^＊＊ level with gaussian 98 program. Based on linear solvation energy theory, lgKow as well as the structural and thermodynamic parameters obtained at this level was taken as theoretical descriptors, and corresponding equation predicting the toxicity of Daphnia magna （-lgEC5o） was thus obtained, in which three parameters were contained, i.e., n-octanol/water partition coefficients （lgKow）, dipole moment of the molecules（ μ） and entropy （S°）. For this equation, R^2 = 0.9582, q^2 = 0.8921 and SD = 0.102. The absolute t-scores of three variables are larger than the standard one in the confidence range of 95%, which confirms the creditability and stability of this model.

关键词： substituted biphenyl linear solvation energy theory,DFT method Daphnia magna toxicity

纳米纤维素晶体物性对碳纳米管分散性及复合膜性能的影响

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精细化工 2025年第2期42卷 332-344页

作者：汪力生宋涛岑钰祁海松韩亭亭华南理工大学制浆造纸工程国家重点实验室广东广州510640 广州大学广州市传感材料与器件重点实验室广东广州510006

以柠檬酸和蔗渣漂白浆板为原材料制备了纳米纤维素晶体(CNCs),通过氯化铁调控CNCs长径比和表面羧基含量;以CNCs为分散剂对碳纳米管(CNTs)进行水相分散得到了CNTs-CNCs分散液,并制备了复合纳米膜(CNCs-CNMs)。结合SEM、EDS、TEM、FTIR、... 详细信息

以柠檬酸和蔗渣漂白浆板为原材料制备了纳米纤维素晶体(CNCs),通过氯化铁调控CNCs长径比和表面羧基含量;以CNCs为分散剂对碳纳米管(CNTs)进行水相分散得到了CNTs-CNCs分散液,并制备了复合纳米膜(CNCs-CNMs)。结合SEM、EDS、TEM、FTIR、粒径分布和Zeta电位表征以及力学性能和电导率测试,考察了CNCs长径比和表面羧基含量对CNTs-CNCs分散液的分散性和CNCs-CNMs的拉伸强度、韧性和电导率的影响。结果表明,CNCs的加入及其长径比的减小和羧基含量的增高对CNTs-CNCs分散液的分散性以及CNCs-CNMs的力学和电学性能具有明显的促进作用。其中,CNCs长径比对CNCs-CNTs分散液的分散性以及CNCs-CNMs的力学性能的影响较羧基含量影响更大,CNCs-CNMs的拉伸强度、韧性和电阻变化率最高分别为72.8 MPa、2.5 J/m^(3)和33.3%;CNCs-CNMs羧基含量对CNCs-CNMs的导电性的影响更为直接,在CNCs长径比0.65 mmol/g时,CNMs电导率均>20 S/cm。

关键词：导电聚合物复合材料碳纳米管纤维素纳米晶分散性力学性能导电性能功能材料

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Characterization of Microporous Activated Carbon Electrodes for Electric Double-layer Capacitors

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Chemical Research in Chinese Universities 2004年第5期20卷 627-630页

作者： MENgQing-han LIULing SONgHuai-he KeyLaboratoryofScienceandTechnologyofControllableChemicalReactionsBUCT MinistryofEducationBeijingUniversityofChemicalTechnologyBeijing100029P.R.China

Activated carbons(ACs) with a wide range of surface areas were made from petroleum coke by means of KOH activation. The electrochemical characterization was carried out for several activated carbons used as polarizable electrodes of electric double-layer capacitors(EDLCs) in an aqueous electrolytic solution. The porous structures and electrochemical double-layer capacitance of the activated carbons were investigated by virtue of nitrogen gas adsorption and constant current cycling(CCC) methods. The relationship among the surface area, pore volume of the activated carbons and specific double-layer capacitance was discussed. It was found that the specific capacitance of ACs increased linearly with the increase of surface area. The presence of mesopores in the activated carbons with very high surface area(>2000 m\+2/g) was not very effective for them to be used as EDLCs. The influence of chemical characteristics of the activated carbons on the double layer formation could be considered to be negligible.

关键词： Micropore activated carbon Electric double layer capacitor Specific capacitance

环糊精葡萄糖基转移酶催化莱鲍迪苷A糖基化短链产物特异性研究

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食品与发酵工业 2025年第05期51卷 29-35页

作者：樊朝悦倪晔刘思言韩瑞枝江南大学工业生物技术教育部重点实验室江南大学生物工程学院

莱鲍迪苷A(rebaudioside A, RA)是从甜叶菊中提取的一类低热量甜味剂，被认为是理想的蔗糖替代品，但其令人不愉快的后苦味限制了其在食品领域的应用。对RA进行适度酶法糖基化被认为是减缓其后苦味有效的方法之一。环糊精葡萄糖基转移酶... 详细信息

莱鲍迪苷A(rebaudioside A, RA)是从甜叶菊中提取的一类低热量甜味剂，被认为是理想的蔗糖替代品，但其令人不愉快的后苦味限制了其在食品领域的应用。对RA进行适度酶法糖基化被认为是减缓其后苦味有效的方法之一。环糊精葡萄糖基转移酶(cyclodextrin glucosyltransferase, CgTase)是目前催化RA糖基化最常用的酶，其主要缺点是反应生成的产物复杂多样，尤其是长链糖基化产物的占比较高，严重影响了产物的口感和品质。该研究探索了不同来源的CgTase催化RA糖基化反应，选择转化率及短链产物特异性均较好的α-CgTase(来源于Paenibacillus macerans)进行研究。通过酶学性质研究及反应条件优化，获得最佳反应条件：以pH 6.0的PBS为反应介质，水溶性淀粉为糖基供体，底物质量比为RA∶水溶性淀粉=1∶1,加酶量25μg/mL,40℃下反应12 h可达平衡，RA的转化率最高达到74.8%,短链产物(RA-ng,n≤2)占总产物的占比为86.5%,较优化前提高了10%。因此，在此条件下可有效提高短链糖苷化RA的特异性，在甜菊糖苷的工业应用中具有更大的潜力。

关键词：莱鲍迪苷A 甜菊糖苷糖基化环糊精葡萄糖基转移酶短链产物特异性

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整合脑组织代谢组学和肠道菌群测序分析研究酸枣仁汤抗抑郁的作用机制

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中草药 2025年第3期56卷 905-918页

作者：常佳东吴江韩瑞秦雪梅杜晨晖闫艳山西大学中医药现代研究中心山西中医药大学中药与食品工程学院

目的整合脑组织代谢组学和肠道菌群测序分析研究酸枣仁汤（Suanzaoren Decoction,SZRD）抗抑郁的作用机制。方法 30只雄性SD大鼠随机分为对照组、模型组、文拉法辛（0.035 g/kg）组和SZRD低、高（12、24 g/kg）剂量组。除对照组外，其... 详细信息

目的整合脑组织代谢组学和肠道菌群测序分析研究酸枣仁汤（Suanzaoren Decoction,SZRD）抗抑郁的作用机制。方法 30只雄性SD大鼠随机分为对照组、模型组、文拉法辛（0.035 g/kg）组和SZRD低、高（12、24 g/kg）剂量组。除对照组外，其余各组大鼠均进行慢性不可预知温和应激（chronic unpredictable mild stress,CUMS）造模，同时ig相应药物，连续给药28 d。基于超高效液相色谱-串联质谱（ultra performance liquid chromatography-tandem mass spectrometry,UPLCMS/MS）技术进行脑组织神经递质测定。基于超高效液相色谱-四极杆飞行时间质谱（ultra performance liquid chromatographyquadrupole time of flight mass spectrometry,UPLC-Q-TOF-MS）技术进行脑组织非靶向代谢组学研究，通过多元统计对代谢轮廓进行分析，以变量重要性投影值（variableimportanceinprojection,VIP）>1、Pgas chromatography-mass spectrometry,gC-MS）对短链脂肪酸含量进行测定。将差异菌群的相对丰度，短链脂肪酸含量和差异代谢物的相对含量与行为学结果进行Spearman分析。结果 SZRD可显著升高脑中的5-羟色胺（5-hydroxytryptamine,5-HT）和谷氨酸（glutamic acid,glu）的含量（Pg/kg）剂量组分别能显著回调15、11个差异代谢物（P<0.05），共同显著回调了10个差异代谢物（P<0.05），且共同作用于苯丙氨酸、酪氨酸和色氨酸生物合成，丙氨酸、天冬氨酸和谷氨酸代谢和三羧酸循环（tricarboxylic acid cycle,TCA）3条代谢通路。同时，SZRD可显著升高乳酸杆菌和粪球菌的丰度（P<0.05）并显著增加丙酸，乙酸和丁酸的含量（P<0.05）。Spearman分析表明，乳酸杆菌等差异菌的丰度及乙酸、丁酸、丙酸的含量与抑郁行为密切相关，差异代谢物的相对丰度与抑郁行为也显著相关。结论 SZRD发挥抗抑郁作用机制可能与回调乳酸杆菌、粪球菌、乙酸、丙酸、丁酸及丙氨酸、天冬氨酸和谷氨酸代谢等通路有关。

关键词：酸枣仁汤抑郁症脑代谢组学肠道菌群短链脂肪酸斯皮诺素酸枣仁皂苷A 乌药碱阿魏酸知母皂苷BⅡ

Dye removal by eco-friendly physically cross-linked double network polymer hydrogel beads and their functionalized composites

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Journal of Environmental Sciences 2019年第4期31卷 81-91页

作者： Yan Kong Yuan Zhuang Zhiyong han Jianwei Yu Baoyou Shi Kun han Haotian Hao Key Laboratory of Drinking Water Science and Technology Research Center for Eco-Environmental SciencesChinese Academy of Sciences College of Petrochemical Engineering Lanzhou University of Technology University of Chinese Academy of Sciences

Hydrogels have attracted large attention in wastewater treatment fields due to their low-cost and good interaction with pollutants,among which novel double network hydrogel is an outstanding *** expand the application of double network hydrogel in water treatment,in this study,eco-friendly physically cross-linked double network polymer hydrogel beads(DAP)are prepared and studied in depth on the mechanism of Methylene Blue(MB)adsorption;and then the polymer hydrogels are further functionalized by inorganic *** adsorption on DAP favors alkaline condition which is due to the increase of electrostatic attraction and adsorption site,and it reaches equilibrium within 10 hr,which is faster than that of the single network hydrogel beads(SAP).Through thermodynamics study,the process shows to be an exothermic and spontaneous *** adsorption isotherms are well fitted by Langmuir model,with a maximum monolayer adsorption capacity of 1437.48 mg/g,which is larger than SAP(1255.75 mg/g).After being functionalized with common inorganic materials including activated carbon,Fe_3O_4and graphene oxide(gO),the composites show to have larger pore sizes and have obvious increases in adsorption capacity especially the one contains *** the composites contains Fe_3O_4are used as heterogeneous Fenton catalyst which shows to have excellent performance in MB *** results indicate the potential of polymer double network to be functionalized in environmental areas.

关键词： Adsorption Alginate Poly(vinyl alcohol) Hydrogel Methylene Blue

Transient curvilinear-coordinate based fully nonlinear model for wave propagation and interactions with curved boundaries

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Journal of Hydrodynamics 2018年第4期30卷 549-563页

作者： Yu-Hsiang Chen Keh-han Wang Department of Civil and Environmental Engineering University of Houston

This paper presents a newly developed 3-D fully nonlinear wave model in a transient curvilinear coordinate system to simulate propagation of nonlinear waves and their interactions with curved boundaries and cylindrical structures. A mixed explicit and implicit finite difference scheme was utilized to solve the transformed governing equation and boundary conditions in grid systems fitting closely to the irregular boundaries and the time varying free surface. The model＇s performance was firstly tested by simulating a solitary wave propagating in a curved channel. This three-dimensional solver, after comparing the results with those obtained from the generalized Boussinesq（g B） model, is demonstrated to be able to produce stable and reliable predictions on the variations of nonlinear waves propagating in a channel with irregular boundary. The results for modeling a solitary wave encountering a vertical cylinder are also presented. It is found the computed wave elevations and hydrodynamic forces agree reasonably well with the experimental measurements and other numerical results.

关键词： Solitary wave curvilinear coordinate transformation curved channel wave scattering hydrodynamic forces

Correlation Function of Potts Model on Bethe Lattice

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Chinese Physics Letters 2000年第8期17卷 549-551页

作者： han Bing CHEN Shu Institute of Physics and Center for Condensed Matter Physics Chinese Academy of SciencesBeijing 100080 Cryogenic Laboratory Chinese Academy of SciencesBeijing 100080

We exactly calculate the partition function and correlation function of Potts model on Bethe type lattice and discuss its phase *** calculation shows that the thermodynamic properties of Potts model on those Bethe lattices which is constructed via connecting the generators by single joint points has the similar character of one dimensional *** phase transition exists only at zero temperature and no finite temperature phase transition occurs.

关键词： transition. Bethe connecting

Soft-rigid coupling grippers:Collaboration strategies and integrated fabrication methods

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Science China(Technological Sciences) 2023年第11期66卷 3051-3069页

作者： CHEN han ZHU JiaQi CAO Yu XIA ZhiSheng CHAI ZhiPing DINg han WU Zhigang State Key Laboratory of Digital Manufacturing Equipment and Technology School of Mechanical Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China Department of Mechanical and Automation Engineering The Chinese University of Hong KongHong Kong SAR 999077China

Continuously increasing applications of robot technologies in unstructured environments put higher requirements on the robotic grippers'performance,such as interaction capability,output force range,and ***,currently,it is hard for either rigid or soft grippers to meet these requirements,as single soft or rigid structures alone are difficult to effectively overcome/alleviate their inherent defects,e.g.,low compliance of rigid structures and low output force of soft *** deal with these difficulties,soft-rigid coupling grippers,or hybrid grippers are ***,the soft-rigid coupling is a promising design that combines soft and rigid structures,in order to exploit their respective advantages,such as the strength of rigid structures and compliance of soft structures,in the same set of the gripper *** the first time,herein,this paper systematically discusses the collaboration strategies of the existing hybrid robotic grippers,by classifying them as Rigid-activesoft-passive,Rigid-passive-soft-active,and *** the same time,we introduce the integrated fabrication methods of hybrid grippers,through which the soft and rigid structures with great stiffness and property differences can be coupled together to construct a stable ***,possible performance improvements on soft-rigid coupling design for gripper systems are discussed.

关键词： grasping grippers hybrid design soft-rigid coupling soft-rigid collaboration

Modeling nitrate aerosol distributions and its direct radiative forcing in East Asia with RAMS-CMAQ

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Particuology 2013年第3期11卷 256-263页

作者： Xiao han Meigen Zhang Baorong Zhou State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of Sciences Xinghua Meteorological Bureau

The geographical and seasonal characteristics in nitrate aerosol and its direct radiative forcing over East Asia are analyzed by using the air quality modeling system RAMS-CMAQ coupled with an aerosol optical properties/radiative transfer module. For evaluating the model performance, nitrate ion concentration in precipitation, and mixing ratios of PMl0, and some gas precursors of aerosol during the whole year of 2007 are compared against surface observations at 17 stations located in Japan, Korea, and China, and the satellite retrieved NO2 columns, The comparison shows that the simulated values are generally in good agreement with the observed ones. Simulated monthly averaged values are mostly within a factor of 2 of the measurements at the observation stations. The distribution patterns of NO2 from simulation and satellite measurement are also similar with each other. Analysis of the distribution features of monthly and yearly averaged mass concentration and direct radiative forcing （DRF） of nitrate indicates that the nitrate aerosol could reach about 25-30% of the total aerosol mass concentration and DRF in Sichuan Basin, Southeast China, and East China where the high mass burden of all major aerosols concentrated. The highest mass concentration and strongest DRF of nitrate could exceed 40 μg/m^3 and -5 Wire2, respectively. It also indicates that other aerosol species, such as carbonaceous and mineral particles, could obviously influence the nitrate DRF for they are often internally mixed with each other.

关键词： Nitrate aerosolDirect radiative forcing CMAQEAN ET AOD