检索结果-南通市图书馆

Journal of Harbin Institute of Technology(New Series) 2006年第2期13卷 164-172页

作者：曾凡林孙毅胡立江 dept. of Astronautic Science and Mechanics Harbin Institute of Technology Harbin 150001 China dept. of Applied chemistry Harbin Institute of Technology Harbin 150001 China

To research the relationship between the elastic parameters and the molecular structures of nano hybrid polyhedral oligomeric silsesquioxanes (POSS) materials, the mechanical properties at different temperatures for three POSS polymers with different molecular architectures, polymerlized norbornene POSS homopolymer (PNPOSS, pedant architecture), γ-(2, 3 glycidoxy) propyl diaminoethane POSS polymer (GPDP, catena architecture) and trimethoxysilylcyclopentyl POSS polymer (TSCP, cage-cage network architecture) were obtained by molecular dynamics simulations based on the Compass force-field. Results indicate that the molecular architectures of the POSS polymers have great influence on the reinforced effects. The effect of the cage-cage network architecture is best, while that of the catena architecture takes second place and the pedant architecture has the least influence comparatively. The reinforced effects of the POSS monomers were examined. The influences of the temperatures on these effects were analyzed also. It may provide some basis for the reasonable applications of the excellent mechanical properties of the organic-inorganic nano-hybrid materials. It may also provide references for exploitation and design of the POSS materials.

关键词：纳米混合材料 POSS 分子动力学模拟弹性参数分子结构

Improvement of Concrete Properties and Reinforcing Steel Inhibition Using a Natural Product Admixture

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 1996年第2期12卷 95-99页

作者： S.H. Tantawi (Building Research Institute, Dokki, Cairo, Egypt)I.Z.Selim (Physical chemistry dept., National Research Center, Dokki, Cairo, Egypt (To whom correspondence should be addressed) Building Research Institute Dokki Cairo Egypt Physical chemistry dept. National Research Center Dokki Cairo Egypt

The use of a natural white juice, taken from magrabe banana stem, as concrete admixture to improve mechanical and physicrvchemical properties of concrete has been studied. The compressive strength, bulk density the free lime liberated during hydration and the combined water content were determined. The results indicate that the admixture acts as a retarder in most cases and as accelerator in some ones. Also, the admixture effect on the corrosion resistance of the reinforcing steel against surrounding aggressive media has been investigated using galvanostatic polarization technique. The addition of 0.2% admixture leads to the more inhibition of the steel

关键词： pH Figure Improvement of Concrete Properties and Reinforcing Steel Inhibition Using a Natural Product Admixture OH

Diclofenac sodium aqueous systems at low concentrations: Interconnection between physicochemical properties and action on hydrobionts

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2020年第2期32卷 177-186页

作者： Irina S.Ryzhkina Yuliya V.Kiseleva Lyaisan I.Murtazina Tatyana V.Kuznetsova Erik R.Zainulgabidinov Igor V.Knyazev Andrew M.Petrov Sergey E.Kondakov Alexander I.Konovalov Arbuzov Institute of organic and Physical chemistry FRC Kazan Scientific CenterRussian Academy of Sciences8 Arbuzov str.Kazan 420088Russia Institute for Problems of Ecology and Mineral Wealth Use of Tatarstan Academy of Sciences 28 Daurskaya Str.Kazan 420087Russia Lomonosov Moscow State University Chemistry Dept.1/3 Lenin HillsMoscow 119899Russia

Diclofenac sodium(DS) is a widely used nonsteroidal anti-inflammatory drug(NSAIDs).NSAIDs are poorly removed during standard wastewater *** consequences of the presence of NSAIDs in rivers and lakes at 10-11–10-8 mol/L are not yet established;therefore, ecotoxicologists have focused their efforts on studying the effect of lowconcentration NSAIDs on fish and hydrobionts, and also on predicting the potential risks to *** provides some information about the bioeffects of some NSAID solutions in low concentrations but there is no physicochemical explanation for these *** the physicochemical patterns of DS solutions in the low range of concentrations and establishing an interconnection between the solutions’ physicochemical properties and bioeffects can provide a conceptually new and important source of information regarding the unknown effects of *** physicochemical properties and action of DS solutions on Ceriodaphnia affinis cladocerans,Paramecium caudatum infusoria, Chlorella vulgaris unicellular green algae, as well as on the growth of the roots of Triticum vulgare wheat seeds, were studied in the calculated concentration range of 1 × 10-3–1 × 10-18 mol/*** relationship between these phenomena was established using the certified procedures for monitoring the toxicity of natural water and *** was shown for the first time that water solutions of DS are dispersed systems in which the dispersed phase undergoes a rearrangement with dilution, accompanied by changes in its size and properties, which affects the nonmonotonic dependences of the system’s physicochemical properties and could cause nonmonotonic changes in action on hydrobionts in the low concentration range.

关键词： Diclofenac sodium Low concentration Aqueous solutions Physicochemical properties Hydrobionts Toxicity

Increase in functional groups for POSS by introducing branched phenylglycidylether

在线全文

学校读者我要写书评

暂无评论

Journal of Harbin Institute of Technology(New Series) 2004年第1期11卷 17-22页

作者：付强胡立江孙德智 dept. of Applied chemistry Harbin Institute of Technology Harbin 150001 China dept. of Environment engineering Harbin Institute of Technology Box 713 Harbin 150001 China

In the selected experimental conditions, firstly, the branched products with functional groups, N-（2-hydroxylpropylphenylether）（3-aminopropyl） triethoxysilane （APES-PGE, containing one hydroxyl group） and N-[di（2-hydroxylpropylphenylether）]（3-aminopropyl） triethoxysilane （APES-PGE2, containing two hydroxyl groups）, were synthesized by reacting 1 mole of （3-aminopropyl）triethoxysilane （APES） with 2 mole of phenylglycidylether （PGE）. Then the hydrolytic condensation of APES-PGE and APES-PGE2 was performed by dissolving 1 g of the corresponding silane in 1.5 ml tetrahydrofuran （THF）, adding water and eventually a catalyst （molar ratios: [H2O]/Si=3, [NaOH]/Si=0.05）, and heating at 50 ℃ for 24 h, allowing continuous evaporation of volatiles. The final products with branches containing hydroxyl groups were polyhedral oligomeric silsesquioxanes （POSS）. The products from two reactions were characterized by standard spectroscopic techniques, gel partition chromatography （GPC）, Fourier-transformed infrared spectroscopy （FTIR） and matrix-assisted ultraviolet laser desorption/ionization time-of-flight mass spectrometry （UV-MALDI-TOF MS）. Additionally, a narrow mass distribution of multifunctionalized POSS was shown by UV-MALDI-TOF MS and assignments of the MS peaks.

关键词： POSS 四氢呋喃硅烷凝胶分配色谱法 GPC Fourier变换红外光谱法

Effect of temperature on electrophoresis velocity of sol particles in water

在线全文

学校读者我要写书评

暂无评论

Journal of Harbin Institute of Technology(New Series) 2002年第4期9卷 348-350页

作者： BAO Zhi-yu(鲍治宇) GU Da-ming(顾大明) dept. of Environment Protection Suzhou University of Science and Technology Suzhou 215011 China Dept. of Chemistry Harbin Institute of Technology Harbin 150090 China

Viscosity of water is affected by temperature and electrophoresis velocity is related to the viscosity of colloid. However, there hasn’t been any direct description about the relation between electrophoresis velocity of colloid and temperature. Based on a large number of tests, the relation between electrophoresis velocity and temperature is established as [v=A+B(T-T°)]. Meanwhile the ratio of the electric charge (q) of sol particles to their radium (r) is a constant is obtained. The results of above were testified in both experiment and theory.

关键词： electrophoresis velocity viscosity temperature iron hydroxide colloidal sol

The effects of coagulants on the structure of PBO materials

在线全文

学校读者我要写书评

暂无评论

Journal of Harbin Institute of Technology(New Series) 2006年第5期13卷 541-544页

作者：李金焕黄玉东孟琳 dept. of Applied chemistry Harbin Institute of Technology Harbin 150001China dept. of Chemical Engineering Daqing Vocational College Daqing 163255 China

PBO materials possess super mechanical properties and high thermal and chemical resistance due to their special rigid-rod backbones with heterocyclic chemical structure and supermolecular microstructure. But these structures may be affected by a series of preparing technologies, among which the coagulant is even more important. In this paper the chemical and microstructure changes of PBO materials coagulated with different solvents were investigated. Analyses of molecular weight and chemical structure of PBO coagulated indicate that the heterocyclic ring of PBO will experience cleavage in coagulation and in this stage water plays an important role. The final structure of PBO materials may involve several intermediate structures lying between benzoxazole and the open ring. Wide-angle X-ray diffraction (WAXD) 2θ scans and scanning probe microscope (SPM) show that the microstructure of PBO materials coagulated in solvents with different properties will change a lot and those coagulants with the smaller rate of diffusion like methanol can cause more ordered molecule alignment containing fewer voids.

关键词：絮凝 PBO 混凝剂机械性能

ZEOLITE－CATALYZED　FRIEDEL－CRAFTS　ACYLATION　OF　AROMATICS∶Ⅲ．SYNTHESIS　OF　4－ACYL　ANISOLE　WITH　USY　CATALYST

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 1996年第3期7卷 233-236页

作者： Yu Dao MA Qi Long WANG Xing Dong JI Chang Ming ZHONG(Department of chemistry,Shandong University, Jinan, 250100)and Qin QIU(Department of Environmental Engineering, Shandong UniversityJinan, 250100) Department of chemistry Shandong University Jinan 250100 dept. of Environmental Engineering Shandong University Jinan 250100

The synthesis with high yield of a series of4-acyl anisole was performed through the Friedel-Crafts reaction of anisole with alkanoic or substituted benzoic acids in thepresence of an ultrastable Y zeolite (USY) catal... 详细信息

关键词： USY CATALYST ACYLATION ACYL

Zeolite－Catalyzed　Friedel－Crafts　Acylation　of　Aromatics．Ⅳ．Nature　of　the　Active　Sites　of　Zeolites

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 1996年第9期7卷 841-844页

作者： Yu Dao MA Qi Long WANG Wei JIANG Be Jun ZUO and Qin QIU(Department of chemistry,Shandong University,Jinan 250100.)(Department of Environmental Engineering, Shandong University,Jinan 250100.) Department of chemistry Shandong University Jinan 250100 dept. of Environmental Engineering Shandong University Jinan 250100

For zeolite-catalyzed Friedel-Crafts acylation of aromatic rings,the Lewis acid sites were found to be active;while the Bronsted acid sites with moderate strength were found to be inactive.

关键词： Nature Aromatics the Active

Addition of Ce as additive to Pb-Ca-Sn-Al grid alloy for lead acid battery

在线全文

学校读者我要写书评

暂无评论

Journal of Harbin Institute of Technology(New Series) 2003年第1期10卷 28-30页

作者：魏杰王东田栾中华郭强 dept. of Applied chemistry Harbin Institute of Technology Lalin Lead Acid Battery Factory

The study on three Pb Ca Sn Al alloys with 0.08%, 0.4% and 1.0% of Ce indicates that the addition of Ce results in an obvious increase in the tensile strength and hardness of the alloys, an increase in the overpotentials of hydrogen and oxygen evolution and the corrosion resistance as well. The study on the corrosion film formed on the alloys by cyclic voltammetry shows that the addition of Ce slows down the formation of corrosion film. It is therefore concluded from the experimental results that the addition of Ce can increase the tensile strength and HB of Pb Ca alloy and the tensile strength and HB of the alloy increase with the increase of Ce; the addition of Ce also increases the hydrogen and oxygen evolution overpotentials of Pb Ca alloy, and when the content of Ce is 1.0%, the alloy has the highest hydrogen and oxygen evolution overpoteatials; the addition of Ce improves the anticorrosion capability of the alloy, and when the content Ce is 1.0%, the alloy has the best anticorrosion capability; and the addition of Ce also slows down the formation of corrosion film.

关键词： Pb-Ca-Sn-A1合金铅钙合金铈铅板蓄电池格子合金电化学性能

Preparation, morphology and mechanical properties of acrylate-modified polyurethane/unsaturated polyester resin graft-IPNs

在线全文

学校读者我要写书评

暂无评论

Journal of Harbin Institute of Technology(New Series) 2003年第1期10卷 7-10页

作者：唐冬雁乔英杰赵连城 dept. of Applied chemistry Harbin Institute of Technology School of Material Science and Technology Harbin Institute of Technology dept. of Chemical Engineering Harbin University of Science and Technology

Acrylate modified polyurethane resin was first synthesized, and interpenetrated with unsaturated polyester resin to form IPNs and gradient IPNs which cured at room temperature. The polymerization process was traced by an IR spectroscopy technique and the simultaneous interpenetrating techniques were determined. The morphology of these IPNs were estimated by TMA and TEM methods. The results indicated that large amount of interpenetrating and entanglement make T g  linked up effectively, and domains between two phases can be in nanometre ranges, which changed with composition ratios. The mechanical properties results showed that IPNs varied from elastomeric to plastic materials. It was noteworthy that, with the introduction of modified groups and the formation of graft construction in IPNs, the miscibility in the systems was improved a lot. These further led to the improved mechanical properties of IPNs with elastomer reinforced and plasticizer toughened as well. The reinforced miscibility between the networks can apparently change mechanical property especially for the gradient ones when the materials are elongated.

关键词：制备形态学机械性质丙烯酸脂改性聚亚安酯不饱和聚酯树脂嫁接互穿聚合物网络