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1.
Amino acid modified polyaspartic acids were evaluated as calcium-scale inhibitors. Feasibility of scale inhibition experiments was analyzed by molecular dynamics simulation and Gaussian optimization, and the scale inhibition mechanism was theoretically analyzed. Scale inhibition performance was studied by scanning electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, static scale inhibition experiments, and electrochemical performance testing, which provided an experimental basis for the molecular dynamics simulation. The experimental results showed that Arg-SA-PASP has better scale inhibition and corrosion inhibition performance than His-SA-PASP. The scale inhibition effect increased with increasing concentration. Electrochemical tests indicated that Arg-SA-PASP is an excellent scale and corrosion inhibitor.  相似文献   
2.
In this paper, we report on a novel family of monodisperse thermo‐sensitive core–shell hydrogel microspheres that is featured with high monodispersity and positively thermo‐responsive volume phase transition characteristics with tunable swelling kinetics, i.e., the particle swelling is induced by an increase rather than a decrease in temperature. The microspheres were fabricated in a three‐step process. In the first step, monodisperse poly(acrylamide‐co‐styrene) seeds were prepared by emulsifier‐free emulsion polymerization. In the second step, poly(acrylamide) or poly[acrylamide‐co‐(butyl methacrylate)] shells were fabricated on the microsphere seeds by free radical polymerization. In the third step, the core–shell microspheres with poly‐ (acrylamide)/poly(acrylic acid) based interpenetrating polymer network (IPN) shells were finished by a method of sequential IPN synthesis. The proposed monodisperse core–shell microspheres provide a new mode of the phase transition behavior for thermo‐sensitive “smart” or “intelligent” monodisperse micro‐actuators that is highly attractive for targeting drug delivery systems, chemical separations, sensors, and so on.  相似文献   
3.
This paper introduces the Force Modulation technique to the study of crystallization process in ferroelectric vinylidene fluoride and trifluoroethylene copolymer films. Using this technique we have successfully visualized ferroelectric crystalline domains and observed that these ferroelectric domains grow out from amorphous phase, unite into strip-like structures, and finally congregate into a union. Force Modulation can weaken the influence of topography on imaging of ferroelectric domains, and reveal more details, which are difficult to be observed in topographical image.  相似文献   
4.
Thin films of block copolymers have been used as templates and scaffolds for the fabrication of arrays of nanostructured materials. In general, a chemical modification of the film or the removal of one of the components by photodegradative methods is required to produce a nanoporous film that serves as a template or scaffold. Here, however, the preferential interaction of one of the components with a solvent is shown to produce a reconstruction of the block copolymer film that, upon drying, leads to the generation of a nanoporous template. The area density of the pores is identical to that of the original copolymer thin film. Since no chemical reactions occurr, the process is fully reversible. Upon heating the copolymer film above its glass‐transition temperature, mobility is imparted to the copolymer and the original copolymer film with oriented domains is recovered. The film reconstruction significantly simplifies the generation of nanoporous templates.  相似文献   
5.
采用胶束氧化还原聚合方法合成了AM/C10AM/AMPS三元疏水缔合共聚物。简介了合成过程,给出了主要的合成参数。保持其他合成条件不变,分别改变疏水单体N 癸基丙烯酰胺C10AM和阴离子单体2 丙烯胺基 2 甲基丙磺酸AMPS在单体总量中的摩尔百分数(0~1.5%和15%~40%),得到了16个共聚物,在45℃、3.67和7.34s-1下测定了用矿化度4000mg/L的模拟大庆盐水配制的1000mg/L共聚物溶液的粘度,讨论了引起粘度变化的原因。有7个样品的粘度能满足大庆油田聚合物驱油的要求(7.34s-1下的粘度大于40mPa·s),其中由1.2%C10AM、35%AMPS及AM合成的共聚物样品粘度最高(61.5mPa·s)。对共聚温度等合成条件的影响作了一般性的讨论。表1参6。  相似文献   
6.
M. Yenigul  I.W. Parsons  J.N. Hay  R.N. Haward 《Polymer》1983,24(10):1313-1316
Ranges of both alternating and random 1:1 copolycarbonates of Bisphenol-A (2,2-bis(4-hydroxyphenyl)propane) and Bisphenol-S (4,4′-dihydroxydiphenyl sulphone) and of Bisphenol-A and 1,4-dimethanoylcyclohexane have been synthesized in order to test the hypothesis that, other things being equal, a more random structured polymer should exhibit superior thermal ageing characteristics. Studies on these materials' mechanical and thermal properties establish that within each pair they are extremely similar and hence the original hypothesis is disproved.  相似文献   
7.
2-丙烯酰胺基-2-甲基丙磺酸(简称AMPS)是优秀的功能高分子材料的单体,其均聚物作牙膏胶黏剂,尤其是加盐牙膏,分散性好,稳定性高。本文研究了AMPS的合成工艺,采用丙烯腈、异丁烯和发烟硫酸为原料,一步合成AMPS,考察了反应物的配比、三氧化硫的浓度、反应温度、反应时间等对产品收率的影响。实验结果表明:当丙烯腈:异丁烯:发烟硫酸=5:1:1(摩尔比),三氧化硫质量分数10%(质量),反应温度20℃,反应时间2h,可得AMPS的收率为90%(质量),产品纯度99%(质量)左右。在最佳工艺条件下合成的AMPS产品为白色粉末,纯度99.1%(质量),熔点187℃,酸值270.7mgKOH/g,Fe离子含量小于0.0003%(质量)。  相似文献   
8.
采用溶液聚合反应合成了2-丙烯酰胺基-2-甲基丙磺酸(AMPS)与单体I的二元共聚物,用作钻井液降黏剂,通过正交实验,确定了共聚物的合成条件为反应温度55℃,引发剂用量1%,单体配比AMPS:I=1:1(质量比),用红外光谱和差热分析法表征了共聚物的组成特征及其热稳定性。结果表明,共聚物的抗温能力可达到200℃以上。  相似文献   
9.
荷负电中空纤维膜用于含聚丙烯酰胺污水的处理   总被引:1,自引:0,他引:1  
以聚砜中空纤维超滤膜为基体,通过紫外辐射接枝2-丙烯酰胺基-2-甲基丙磺酸(AMPS)制备荷负电膜,并用于含聚丙烯酰胺(PAM)污水的处理.结果表明:荷电膜通量下降率小于原膜,稳定通量是原膜的1.4倍,对PAM的去除率大于原膜,达到82%;操作压力增大,荷电膜通量衰减加快,PAM的去除率降低;随着PAM初始浓度的增大,荷电膜通量下降率先增大后基本不变;过滤不同浓度的含PAM污水,荷电膜对PAM的去除率均大于80%,COD去除率均在70%以上.在25℃,0.10 MPa下反洗20 min后荷电膜通量恢复率比原膜提高20.17%,重复使用3次后,通量恢复率仍保持在92%以上.  相似文献   
10.
为改善环氧树脂E-44的水溶性,以丙烯酸(AA)和2-甲基-2-丙烯酰胺基-丙磺酸(AMPS)为接枝共聚的单体对环氧树脂进行水性化改性.研究了引发剂、不同单体及比例和反应条件对接枝共聚物水分散稳定性的影响并通过红外光谱对产物进行了表征.结果表明,以2.71 wt%的BPO为引发剂、以体积比1∶1的无水乙醇-乙二醇单甲醚为混合溶剂,在接枝共聚反应温度110℃,下用质量比为1∶1的AA/AMPS对等质量的环氧树脂E-44进行改性,得到的改性环氧树脂水性化改性效果最好,乳液离心稳定性和贮存稳定性最高.  相似文献   
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