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81.
本文研究了配糖蛋白B-阳离子丙烯酸树脂微胶囊的形态、粒径及粒径分布,并在模拟胃液的酸性缓冲液中进行了微胶囊的溶解释放试验。结果表明该微胶囊能溶于人体的胃液中,可配制适合儿童口服的混悬剂。  相似文献   
82.
A chitosan resin functionalized with 3-nitro-4-amino benzoic acid moiety (CCTS-NABA resin) was newly synthesized for the collection/concentration of trace molybdenum by using cross-linked chitosan (CCTS) as base material. The carboxyl group of the moiety was chemically attached to amino group of cross-linked chitosan through amide bond formation. The adsorption behavior of molybdenum as well as other 60 elements on the resin was examined by passing the sample solutions through a mini-column packed with the resin. After the elution of the elements collected on the resin with 1 M HNO3, the eluates were analyzed by inductively coupled plasma-mass spectrometry (ICP-MS) and atomic emission spectrometry (ICP-AES).

The CCTS-NABA resin can adsorb several metal ions, such as vanadium, gallium, arsenic, selenium, silver, bismuth, thorium, tungsten, tin, tellurium, copper, and molybdenum at appropriate pHs. Among these metal ions, only molybdenum could be adsorbed almost completely on the resin at acidic regions. An excellent selectivity toward molybdenum could be obtained at pH 3–4. The adsorption capacity of CCTS-NABA resin for Mo(VI) was 380 mg g−1 resin. Through the column pretreatment, alkali and alkaline earth metals in river water and seawater samples were successfully removed.

The CCTS-NABA resin was applied to the adsorption/collection of molybdenum in river water and seawater samples. The concentrations of molybdenum in river water samples were found in the range of 0.84 and 0.95 ppb (ng g−1), whereas molybdenum in seawater was about 9 ppb. The validation of the proposed method was carried out by determining molybdenum in the certified reference materials of SLRS-4, CASS-4, and NASS-5 after passing through the CCTS-NABA resin; the results showed good agreement with the certified values.  相似文献   

83.
弱酸树脂D113对S-腺苷-L-蛋氨酸的交换行为及分离应用研究   总被引:1,自引:0,他引:1  
考察了S-腺苷-L-蛋氨酸 (S-adenosyl-L-methionine, SAM) 在弱酸树脂争光D113上的静态吸附及分离行为,利用Langmuir等温式对平衡等温线进行了拟合,实验表明,随着pH的提高,平衡交换量增加,提高温度和SAM的初始浓度在一定程度上能促进内扩散过程,利用D113树脂在f 1.7×30.0cm小型柱上从酵母提取液中分离SAM的得率为90%以上,纯度达87%以上。  相似文献   
84.
Ti4+修饰阳离子交换树脂催化制备环已烯   总被引:5,自引:0,他引:5  
在Ti^4 修饰阳离子交换树脂催化剂上进行了环己醇脱水制备环己烯的反应,考察了催化剂吸附毗啶的FT-IR,证实了该催化剂表面具有Bronsted酸和Lewis酸性住是催化环己烯脱水反应的物质基础,实验结果表明:修饰树脂具有较高的热稳定性,Ti^4 交换容量对阳离子交换树脂的催化活性存在着明显的影响,催化剂对环己醇脱水制环己烯反应的活性高,并得到该反应的优化条件如下:环己醇40g,催化剂5g,反应温度175℃,反应时问60min,在此条件下,环己烯的产率达89%。  相似文献   
85.
时间分辨激光光散射测量系统   总被引:1,自引:1,他引:1  
自选设计,装配了一套时间分辨的激光光散射测量系统,该系统摄像机,录像机,计算机和自编的软件实现了一体化的数据采集,显示和分析过程,本文给出了该系统的应用实例,球晶的光散射和环氧树脂的固化反应诱导的相分离过程。  相似文献   
86.
The influence of the resin/diamine ratio on the properties of the system diglycidyl ether of bisphenol A (BADGE n=0/m-xylylenediamine) (m-XDA) was studied. Variation of this ratio resulted in significant effects on the cure kinetics and final dynamic mechanical properties of the product material. The study was made in terms of storage modulus (E′), vss modulus (E″) and molecular mass between cross-links (Mc) at different ratios. Two geometries (cylindrical and rectangular) were considered. The influence of temperature was studied through the activation energy (Ea>), which depends on the epoxy/amine ratio and the geometry of the samples. Glass transition temperatures (Tg>) and glass transition temperatures for thermosets with null degree of conversion (Tgo>) were determined by DSC. Tg> decreases when amounts of curing agent greatly in excess of the stoichiometric composition were used. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
87.
2-HBR负载树脂分离富集金的研究及其分析应用   总被引:6,自引:0,他引:6  
本文探讨了2-羟基苄叉罗丹宁(2-HBR)负载树脂对金的吸附性能及用AAS吸附金的酸效应、吸附动力学、吸附机理、吸附热力学、动态试验等。  相似文献   
88.
Two novel chelating resins were prepared by anchoring ethylenediamine to crosslinked polystyrene via a spacer containing sulfide. Their structures were characterized by Fourier transform-infrared spectra (FTIR) and scanning electron microscopy (SEM). Porous structure parameters of the resins were measured by ASAP 2020 using BET and BJH methods. Their adsorption capacities for several heavy metal ions especially Hg2+ were investigated. The results showed that for the two resins, the more N contents did not mean the better adsorption capacity and the saturated adsorption capacity of poly(2-ethylenediamidomercaptomethylstyrene) (PSM-EDA) for Hg2+ could reach to 3.0 mmol/g at room temperature. Isothermal adsorptions of the resins for Hg2+ could be described by Langmuir formula. The adsorption mechanism of the resins for Hg2+, Cu2+ and Ag+ was confirmed by X-ray photoelectron spectroscopy (XPS) and FTIR.  相似文献   
89.
Epoxy resins in the solid state, liquid state and during polymerisation were treated by microwave oxygen plasma and analysed by FTIR spectra. Curing, etching and oxidation kinetics of epoxy resin were observed. In the liquid resin and polymerising mixture the effect of structure modification was observed more intensively than in the case of solid sample due to a mixing process. A modification of bulk layers of liquid epoxy resin was observed under plasma action. The polymerisation reaction of epoxy resin with amine hardening agent can be released in plasma discharge at low pressure.  相似文献   
90.
The flame retardant effect of newly synthesized phosphorus-containing reactive amine, which can be used both as crosslinking agent in epoxy resins and as a flame retardant, was investigated. The effect of montmorillonite and sepiolite additives on the fire induced degradation was compared to pristine epoxy resin. The effect of combining the organophosphorous amine with clay minerals was also studied. It could be concluded that the synthesized phosphorus-containing amine, TEDAP can substitute the traditional epoxy resin curing agents providing additionally excellent flame retardancy: the epoxy resins flame retarded this way reach 960 °C GWFI value, 33 LOI value and V-0 UL-94 rating - compared to the 550 °C GWFI value, 21 LOI value and “no rate” UL-94 classification of the reference epoxy resin. The peak of heat release was reduced to 1/10 compared to non-flame retarded resin, furthermore a shift in time was observed, which increases the time to escape in case of fire. The flame retardant performance can be further improved by incorporating clay additives: the LOI and the HRR results showed that the optimum of flame retardant effect of clay additives is around 1 mass% filler level in AH-16-TEDAP system. Applying a complex method for mechanical and structural characterization of the intumescent char it was determined that the flame retarded system forms significantly more and stronger char of better uniformity with smaller average bubble size. Incorporation of clay additives (owing to their bubble nucleating activity) results in further decrease in average bubble diameter.  相似文献   
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