检索结果-南通市图书馆

Chinese Journal of Polymer Science 2015年第8期33卷 1186-1195页

作者： ce Tian 凌君 You-qing Shen MOE Key laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and EngineeringZhejiang University Department of Chemical and Biological Engineering Zhejiang University

Polypeptides and polypeptoids were widely used as biomedical materials because of their good biocompatibility. In this work we reported a series of pH-responsive copolypeptides and polypeptide-polypeptoid block copolymers, i.e. random copolymers of l-glutamic acid （Glu） with l-leucine （leu） [poly（Glu-r-leu）s], as well as their block copolymers with polysarcosine （polySar）. Well-defined poly（Glu-r-leu）s with predictable compositions and molecular weights were synthesized by ring opening polymerization of corresponding N-carboxyanhydride monomers. We investigated the relationship between hydrophilicity-hydrophobicity transition and copolymer composition. With increasing leu fraction, both the pH value of cloud point and the micellar size increased. Poly（Glu-r-leu） with 60% leu exhibited a cloud point at the pH of 5.0 to 6.0 the same as that in endosome and lysosome. Poly（Glu-r-leu）-b-polySars assembled in phosphate buffer and performed pH-responsive morphology change from orbicular micelles at high pH to worm-like micelles at low pH. They were potential pH-responsive carriers for drug and gene delivery to enhance cargo release in cellules.

关键词： α-Amino acid NCA Random/block copolypeptide pH-Responsive Hydrophilicity-hydrophobicity transition.

Adsorption of As(Ⅲ)from aqueous solution based on porous magnetic/chitosan/ferric hydroxide microspheres prepared via electrospraying

在线全文

学校读者我要写书评

暂无评论

Science China Chemistry 2013年第5期56卷 678-684页

作者： VU Dinhthao lI Xiang WANG ce Alan G. MacDiarmid Institute Jilin University

Porous chitosan（CS）/magnetic（Fe304）/ferric hydroxide（Fe（OH）3） microsphere as novel and low-cost adsorbents for the removal of As（Ill） have been synthesized via the electrospraying technology by a simple process of two steps. Characterization of the obtained adsorbents was studied by transmission electron microscopy （TEM）, scanning electron microscopy （SEM）, X-ray photoelectron spectroscopy （XPS）, and X-ray diffraction （XRD）. The adsorption kinetics and equilibrium isotherms were in- vestigated in batch experiments. The langmuir, Freundlich isotherm and pseudo-second order kinetic models agree well with the experimental data. The adsorption of As（III） onto CS/Fe3OdFe（OH）3 microspheres occurred rapidly and reached adsorption equilibrium after about 45 min. The maximum adsorption capacity of CS/Fe3OJFe（OH）3 microspheres, calculated by the langmuir isotherm model, was 8.47 mg g 1, which is higher than that of CS/Fe304/Fe（OH）3 prepared by the conventional method （4.72 mg g-l）. The results showed that the microspheres had a high adsorption capacity for As（III） and a high separation efficiency due to their microporous structure and superparamagnetic characteristics. Present research may eventually lead to a simple and low cost method for fabricating microporous materials and application for removal of arsenic from aqueous solution.

关键词： adsorption electrospraying magnetic materials chitosan arsenic

Nanosilver anchored alginate/poly(acrylic acid/acrylamide) double-network hydrogel composites for efficient catalytic degradation of organic dyes

在线全文

学校读者我要写书评

暂无评论

Frontiers of Chemical Science and Engineering 2023年第7期17卷 893-905页

作者： Fan Zhang ce Gao Shang-Ru Zhai Qing-Da An liaoning Key lab of lignocellulose Chemistry and BioMaterials Liaoning Collaborative Innovation Center for Lignocellulosic BiorefineryCollege of Light Industry and Chemical EngineeringDalian Polytechnic UniversityDalian 116034China

A novel alginate/poly(acrylic acid/acrylamide)double-network hydrogel composite with silver nanoparticles was successfully fabricated using the sol–gel *** presence of carboxyl and amide groups in the network structure provided abundant active sites for complexing silver ions,facilitating the in situ reduction and confinement of silver *** batch experiments,the optimal silver loading was 20%,and 5 mmol·l^(–1) of p-nitrophenol was completely degraded in 113 s with a rate constant value of 4.057×10^(−2) s^(–1).In the tap water system and simulated seawater system,the degradation time of p-nitrophenol at the same concentration was 261 and 276 s,respectively,with a conversion rate above 99%.In the fixed-bed experiment,the conversion rate remained above 74%after 3 h at a flowing rate of 7 ml·min^(–1).After 8 cycling tests,the conversion rate remained at 98.7%.Moreover,the catalyst exhibited outstanding performance in the degradation experiment of four typical organic dyes.

关键词： double-network hydrogel dye degradation silver nanoparticles alginate

Perspective: voltage control of magnetization in multiferroic heterostructures

在线全文

学校读者我要写书评

暂无评论

National Science Review 2019年第4期6卷 621-624页

作者： Jia-Mian Hu ce-Wen Nan long-Qing Chen Department of Materials Science and Engineering University of Wisconsin–Madison State Key lab of New ceramics and Fine Processing School of Materials Science and Engineering Tsinghua University Department of Materials Science and Engineering Pennsylvania State University

Multiferroic materials host ferromagnetic and ferroelectric orders either in the same phase, or separately in distinct magnetic and ferroelectric phases. In some multiferroic materials, the two distinct ferroic orders can be strongly coupled (namely, magnetoelectric coupling)[1], which can be exploited for achieving new functionalities. For example, it allows for controlling magnetization with a voltage rather than a magnetic-field-generating electric current, providing an energy-efficient

关键词： Perspective voltage control of magnetization in multiferroic heterostructures AFM

Efficient adsorption of As(V) on poly(acrylo-amidino ethylene amine) nanofiber membranes

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Chinese Science Bulletin 2013年第14期58卷 1702-1707页

作者： VU Dinhthao lI Xiang WANG ce Alan G. MacDiarmid Institute Jilin University

Poly(acrylo-amidino ethylene amine) (PAEA) nanofiber membranes have been synthesized by combining the electrospinning technique and subsequent chemical modification. The membranes were used to remove As(V) from aqueous solution. The adsorption kinetics, equilibrium isotherms, and pH effect were investigated in batch experiments. The langmuir isotherm and pseudo second-order kinetic models agree well with the experimental data. The PAEA nanofibers are effective for As(V) adsorption at pH 3. Experimental results showed that the maximum adsorption capacity of the PAEA nanofibers with As(V) is 76.92 mg g-1 , which is much higher than that of the PAEA microfibers (27.62 mg g-1 ). The adsorption rate of PAEA nanofibers is faster than that of PAEA microfibers due to its higher specific surface area. The PAEA nanofibers can be used as an effective adsorbent for the removal of As(V) in aqueous solution due to high adsorption capacity and short adsorption time to achieve equilibrium.

关键词：纳米纤维膜吸附动力学丙烯腈乙烯胺 langmuir 脒平衡等温线动力学模型

Synthesis and Crystal Structure of 1-(4-Chlorophenyl)-2-cyano-3-amino-3a-hydroxy- 3a,3b,6,7-tetrahydrobenzo[4,5]indene

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Structural Chemistry 2005年第12期24卷 1393-1396页

作者： SHI Da-Qing SHI Chun-ling RONG liang-ce Department of Chemistr） Xuzhou Normal University Xuzhou 221116 China The Key laboratory of Biotechnology on Medical Plants of Jiangsu Province Xuzhou 221116 China

The title compound 1-（4-chlorophenyl）-2-cyano-3-amino-3a-hydroxy-3a,3b,6,7- tetrahydro-benzo[4,5]indene 2, has been synthesized by the reductive cyclization of 2-cyano-3- （4-chlorophenyl）-3-（1-tetralon-2-yl） propionitrile 1 induced by low-valent titanium reagent and its structure was determined by single-crystal X-ray diffraction. The crystal belongs to monoclinic, space group C2/c with a = 28.244（7）, b = 14.401（3）, c = 21.245（3）A,β= 115.71（2）°, V = 7786（3）A^3, Mr= 696.13, Dc = 1.188 g/cm^3, Z = 8,μ（MoKα） = 0.208 mm^-1, F（000） = 2916, R = 0.0783 and wR = 0.2350. X-ray analysis reveals that the five-membered ring （C（7）～C（l l）） adopts an envelop conformation, while the six-membered ring （C（10）～C（14）, C（19）） has a half-chair conformation. Meanwhile, intermolecular H-bond interactions result in the formation of polymer.

关键词： tetrahydrobenzoindene synthesis crystal structure low-valent titanium

Effect of Heavy Metals （Cd, Cu） on the Gametophytes of laminaria japonica Aresch

在线全文

学校读者我要写书评

暂无评论

Journal of Integrative Plant Biology 2005年第8期47卷 942-951页

作者： Nai-Hao YE Guang-ce WANG Cheng-Kui TSENG Key laboratory of Experimental Marine Biology Institute of Oceanology the Chinese Academy of Sciences Qingdao 266071 China Graduate School the Chinese Academy of Sciences Beijing 100039 China

Effects of various concentrations of two heavy metals, namely Cd and Cu, on gametophytes of laminariajaponica Aresch were determined by recording morphological changes of gametophytes, determining pH values and the heavy metal content of the culture solution, calculating the germination rate of sporophytes, and observing heavy metal （Cd） distribution using a fluorescence microscope. The results showed that heavy metals damaged the gametophytes, and were even lethal, and that the higher the concentration of heavy metal ions, the greater the injury to gametophytes. Gametophytes could not survive in culture solutions containing more than 100 mg/l Cd and 50 mg/l Cu and were only able to survive in culture solution containing a mixture of Cd and Cu up to a concentration of 10 mg/l, which indicates that gametophytes have a higher tolerance to Cd than Cu and that multiple heavy metal ions in solution markedly aggravate the damage to gametophytes compared with individual heavy metal ions. With increases in the concentration of the heavy metal, the burgeoning rate of sporophytes decreased acutely, and solutions containing multiple heavy metal ions caused even more marked harm to sporophytes than solutions containing a single heavy metal ion, because most sporophytes died in mixed solutions. The pH value of the culture medium dropped immediately at the beginning （the first day） of treatment, increased over the following days, and then decreased again. The pH of culture media containing multiple heavy metal ions showed greater variation than media containing a single heavy metal ion, with the extent of the decrease in pH of culture media containing multiple ions being greatest during the last period of the experiment. With increases in the concentration of heavy metals, the capacity of gametophytes to accumulate these ions increased. The blue fluorescent light emitted by the Cd-and Cd-binding protein complex existing in gametophytes in media containing different concentrations

关键词： Cd Cu gametophyte heavy metals laminariajaponica.

3D printed hydrogel for soft thermo-responsive smart window

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Extreme Manufacturing 2022年第2期4卷 184-193页

作者： lei Chen Guihui Duan ce Zhang Ping Cheng Zhaolong Wang College of Mechanical and Vehicle Engineering Hunan UniversityChangsha 410082People’s Republic of China Qian Xuesen laboratory of Space Technology China Academy of Space Technology(CAST)Beijing 10094People’s Republic of China MOE Key laboratory for Power Machinery and Engineering School of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai 200240People’s Republic of China

Smart windows with tunable optical properties that respond to external environments are being developed to reduce energy consumption in *** the present study,we introduce a new type of 3D printed hydrogel with amazing flexibility and stretchability(as large as 1500%),as well as tunable optical performance controlled by surrounding *** hydrogel on a PDMS substrate shows transparent-opaque transition with high solar modulation(ΔT_(sol))up to 79.332% around its lower critical solution temperature(l_(CST))while maintaining a high luminous transmittance(T_(lum))of 85.847% at 20℃.In addition,selective transparent-opaque transition above lCST can be achieved by patterned hydrogels which are precisely fabricated via a projection micro-stereolithography based 3D printing *** hydrogel promises great potential applications for the next generation of soft smart windows.

关键词： 3D printing thermal response hydrogel tunable optical properties smart window

ReslNet:deep residual lSTM network with longer input for action recognition

在线全文

学校读者我要写书评

暂无评论

Frontiers of Computer Science 2022年第6期16卷 41-49页

作者： Tian WANG Jiakun lI Huai-Ning WU ce lI Hichem SNOUSSI Yang WU Institute of Artificial Intelligence Beihang UniversityBeijing100191China School of Automation Science and Electrical Engineering Beihang UniversityBeijing100191China College of Electrical and Information Engineering Lanzhou University of TechnologyLanzhou730050China Institute Charles Delaunay-lM2S FRE CNRS 2019 University of Technology of TroyesTroyes10010France Institute for Research Initiatives Nara Institute of Science and TechnologyNara630-0192Japan

Action recognition is an important research topic in video analysis that remains very *** recognition relies on learning a good representation of both spatial information(for appearance)and temporal information(for motion).These two kinds of information are highly correlated but have quite different properties,leading to unsatisfying results of both connecting independent models(e.g.,CNN-lSTM)and direct unbiased co-modeling(e.g.,3DCNN).Besides,a long-lasting tradition on this task with deep learning models is to just use 8 or 16 consecutive frames as input,making it hard to extract discriminative motion *** this work,we propose a novel network structure called ReslNet(Deep Residual lSTM network),which can take longer inputs(e.g.,of 64 frames)and have convolutions collaborate with lSTM more effectively under the residual structure to learn better spatial-temporal representations than ever without the cost of extra computations with the proposed embedded variable stride *** superiority of this proposal and its ablation study are shown on the three most popular benchmark datasets:Kinetics,HMDB51,and *** proposed network could be adopted for various features,such as RGB and optical *** to the limitation of the computation power of our experiment equipment and the real-time requirement,the proposed network is tested on the RGB only and shows great performance.

关键词： action recognition deep learning neural network

General synthesis of Pt and Ni co-doped porous carbon nanofibers to boost HER performance in both acidic and alkaline solutions

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical letters 2023年第2期34卷 263-267页

作者： Jiaqi Xu Mengxiao Zhong Na Song ce Wang Xiaofeng lu Alan G.MacDiarmid Institute College of ChemistryJilin UniversityChangchun 130012China

It is essential to develop efficient electrocatalysts to generate hydrogen from water electrolysis for hydrogen economy. In this work, platinum(Pt) and nickel(Ni) co-doped porous carbon nanofibers(Pt/NiPCNFs) with low Pt content were prepared via an electrospinning, carbonization and galvanic repl.cement reaction. Because of the high electrical conductivity, abundant electrochemical active sites and synergistic effect between Pt and Ni nanoparticles, the optimized Pt/Ni-PCNFs catalyst shows an excellent HER activity with overpotentials of 20 m V in 0.5 mol/l H_(2)SO_(4) and 46 m V in 1 mol/l KOH at a current density of10 m A/cm^(2). Furthermore, over 35-h long-term stability has been achieved without significant *** work provides a simple route to prepare highly efficient electrocatalysts for water splitting and has great prospects in the field of renewable energy.

关键词： Electrospinning Platinum Nickel Porous carbon nanofibers Hydrogen evolution reaction