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1.
王梓民  石海信  王爱荣  王锋  何强 《精细化工》2019,36(6):1198-1202,1209
以两性离子单体二甲氨基丙基丙烯酰胺-1-羧酸(ZM)、木薯淀粉(CSt)和聚乙烯醇(PVA)为主要原料,采用"一锅法",通过冷冻交联制备ZM接枝共聚CSt-PVA互穿网络复合凝胶(ZPG2)。使用FTIR、TGA、POM、SEM-EDS对ZPG2进行了表征,评价了ZPG2对Cu~(2+)的静态吸附效果。结果表明:300℃以下,ZPG2的热稳定性良好;ZM的存在可产生反聚电解质效应和化学配位效应,显著提高凝胶吸附能力;在吸附温度25℃、ZPG20.1 g、Cu~(2+)质量浓度2×10~3 mg/L、溶液体积100 mL时,饱和吸附量为199 mg/g;吸附过程符合Langmuir等温吸附模型和准二级动力学模型。  相似文献   
2.
介绍土壤易溶盐试验的样品采集与制备,提出试验过程中应注意的事项,以供借鉴.  相似文献   
3.
This work describes the synthesis and anti-fouling properties of poly(vinylidene fluoride) membrane, grafted with carboxybetaine-based zwitterions. An amphiphilic copolymer, poly(vinylidene fluoride)-graft- poly(N,N-dimethylamino-2-ethylmethacrylate) (PVDF-g-PDMAEMA), was synthesized by radical graft copolymerization, followed by casting the copolymer into a flat membrane, by an immersed phase inversion method. PVDF-g-PDMAEMA membrane was reacted with sodium chloroacetate (SCA) to yield a carboxybetaine-based zwitterionic surface. The membrane showed significantly enhanced hydrophilicity, due to the hydration ability of carboxybetaine-based zwitterions, which inhibited protein adsorption. Compared to pristine PVDF-g-PDMAEMA membrane, carboxybetaine-based zwitterionic membrane exhibited a higher flux recovery in the cyclic filtration.  相似文献   
4.
基于离子液体的可设计性与功能化,综述了近年来出现的新型表面活性离子液体的结构、性能、聚集行为及其应用的效果,主要包括两性表面活性离子液体、响应型表面活性离子液体、手性表面活性离子液体等。  相似文献   
5.
Observed pseudo‐first‐order rate constants (ko) for the reaction between CO2 and 2‐((2‐aminoethyl) amino) ethanol (AEEA) were measured using the stopped‐flow technique in an aqueous system at 298, 303, 308 and 313 K, and in non‐aqueous systems of methanol and ethanol at 293, 298, 303 and 308 K. Alkanolamine concentrations ranged from 9.93 to 80.29 mol m?3 for the aqueous system, 29.99–88.3 mol m?3 for methanol and 44.17–99.28 mol m?3 for ethanol. Experimentally obtained rate constants were correlated with two mechanisms. For both the aqueous‐ and non‐aqueous‐AEEA systems, the zwitterion mechanism with a fast deprotonation step correlated the data well as assessed by the reported statistical analysis. As expected, the reaction rate of CO2 in the aqueous‐AEEA system was found to be much faster than in methanol or ethanol. Compared to other promising amines and diamines studied using the stopped‐flow apparatus, the pseudo‐first‐order reaction rate constants were found to obey the following order: PZ (cyclic‐diamine) > EDA (diamine) > AEEA (diamine) > 3‐AP (primary amine) > MEA (primary amine) > EEA (primary amine) > MO (cyclic‐amine). The reaction rate constant of CO2 in aqueous‐AEEA was double that in aqueous‐MEA, and the difference increased with an increase in concentration. All reaction orders were practically unity. With a higher capacity for carbon dioxide and a higher reaction rate, AEEA could have been a good substitute to MEA if not for its high thermal degradation. AEEA kinetic behaviour is still of interest as a degradation product of MEA. © 2012 Canadian Society for Chemical Engineering  相似文献   
6.
烯烃臭氧化反应中两性离子反应新进展   总被引:1,自引:0,他引:1  
介绍了烯烃臭氧化反应,论述了臭氧化反应中生成的两性离子与醇、氧化胺、水、路易斯酸的反应以及两性离子的异构化反应及其在合成相关化工、医药、香料产物方面的应用,并对近十年来两性离子反应的研究进展进行了综述。  相似文献   
7.
J Yuan  J Zhu  CH Zhu  J Shen  SC Lin 《Polymer International》2004,53(11):1722-1728
A possible approach to improve the blood compatibility of poly(ether urethane)s (PU) involves the covalent attachment of key molecules on its surface. The purpose of the present study was to design and synthesise a novel non‐thrombogenic biomaterial by modifying the surface of the PU with a zwitterionic monomer of sulfobetaine via a Jeffamine spacer. In this study, sulfobetaine was grafted onto a PU surface through the following reaction steps: (1) The PU surface was activated with hexamethylene diisocyanate (HDI) in toluene at 50 °C in the presence of di‐n‐butyltin dilaurate (DBTDL) as a catalyst. The extent of the reaction was measured by ATR‐FTIR spectra; a maximum number of free NCO groups was obtained after a reaction time of 90 min. (2) One cap of Jeffamine was reacted with isocyanate groups bound on the surface, so Jeffamine was introduced. (3) The PU surface terminated by Jeffamine was recoupled with isocyanate groups by HDI. (4) The hydroxyl groups of 4‐dimethylamino‐1‐butanol (DMAB) or 2‐dimethylaminoethanol (DMAE) were allowed to react with the isocyanate groups capped on Jeffamine. (5) Sulfobetaines were constructed on the surface through the ring‐opening reaction between tertiary amine and 1,3‐propanesultone (PS). It was confirmed by ATR‐FTIR and XPS that the grafted surfaces were composed of sulfobetaine. The results of the contact‐angle measurements and water absorption showed that they were strongly hydrophilic. The results of this platelet adhesion experiment as a preliminary test showed that PU grafted with sulfobetaine has good blood compatibility featured by the low platelet adhesion. Copyright © 2004 Society of Chemical Industry  相似文献   
8.
9.
Nanodiamond (ND) is a versatile and promising material for bioapplications. Despite many efforts, agglomeration of nanodiamond and the nonspecific adsorption of proteins on the ND surface when exposed to biofluids remains a major obstacle for biomedical applications. Here, the functionalization of detonation nanodiamond with zwitterionic moieties in combination with tetraethylene glycol (TEG) moieties immobilized by click chemistry to improve the colloidal dispersion in physiological media with strong ion background and for the simultaneous prevention of nonspecific interactions with proteins is reported. Based on five building blocks, a series of ND conjugates is synthesized and their performance is compared in biofluids, such as fetal bovine serum (FBS) and Dulbecco's modified Eagle medium (DMEM). The adsorption of proteins is investigated via dynamic light scattering (DLS) and thermogravimetric analysis. The colloidal stability is tested with DLS monitoring over prolonged periods of time in various ratios of water/FBS/DMEM and at different pH values. The results show that zwitterions efficiently promote the anti‐fouling properties, whereas the TEG linker is essential for the enhanced colloidal stability of the particles.  相似文献   
10.
Hydrogel electrolytes have high room-temperature conductivity and can be widely used in energy storage device. However, hydrogels suffer from the inevitable freezing of water at subzero temperatures, resulting in the diminishment of their conductivity and mechanical properties. How to achieve high conductivity without sacrificing hydrogels’ flexibility at subzero temperature is an important challenge. To address this challenge, a new type of zwitterionic polymer hydrogel (polySH) electrolytes is fabricated. The anionic and cationic counterions on the polymer chains facilitate the dissociation of LiCl. The antifreezing electrolyte can be stretched to a strain of 325% and compressed to 75% at −40 °C and possesses an outstanding conductivity of 12.6 mS cm−1 at −40 °C. A direct hopping migration mechanism of hydrated lithium-ion through the channel of zwitterion groups is proposed. The polySH electrolyte-based-supercapacitor (SC) exhibits a high specific capacitance of 178 mF cm−2 at 60 °C and 134 mF cm−2 at −30 °C with a retention of 81% and 71% of the initial capacitance after 10 000 cycles, respectively. The overall merits of the electrolyte will open up a new avenue for advanced ionic conductors and energy storage device in practical applications.  相似文献   
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