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31.
王婷  魏奇  付强  李伟  王世伟 《应用化学》2022,39(9):1321-1344
钙钛矿太阳能电池作为第3代新概念太阳能电池,具有高光电转换效率、低成本和可柔性加工等优点,近年来发展迅速,其光电转换效率从一开始的3.8%增长到近期的25.5%,逐渐比肩硅电池,已接近商业化应用水平。目前,实现钙钛矿太阳能电池产业应用的关键环节在于电池封装,它不仅可以解决钙钛矿光伏器件稳定性问题,还可以实现电池安全、环保和延长使用寿命等要求。结合近十几年来钙钛矿光伏电池封装材料和封装工艺两方面的发展现状,文中介绍了钙钛矿电池封装领域取得的成果和存在的不足,讨论了目前现有封装技术的优缺点,以及它们适用的不同器件类型。着重在不同温度湿度条件下,比较了不同封装材料性能、封装工艺条件对钙钛矿电池效率及稳定性的影响,归纳出影响钙钛矿电池薄膜封装效果的3个关键因素: 聚合物的弹性模量、水蒸气透过率、加工温度。比较了不同聚合物薄膜封装材料适宜的加工温度、优缺点及加工成本。可以看出,随着钙钛矿光伏电池工业化需求的强烈增长和人们对其封装材料研究的不断深入,研究适合大面积生产和光伏建筑一体化的新型功能聚合物封装材料将是必然趋势。  相似文献   
32.
Formylation is one of the newly discovered post-translational modifications in lysine residue which is responsible for different kinds of diseases. In this work, a novel predictor, named predForm-Site, has been developed to predict formylation sites with higher accuracy. We have integrated multiple sequence features for developing a more informative representation of formylation sites. Moreover, decision function of the underlying classifier have been optimized on skewed formylation dataset during prediction model training for prediction quality improvement. On the dataset used by LFPred and Formator predictor, predForm-Site achieved 99.5% sensitivity, 99.8% specificity and 99.8% overall accuracy with AUC of 0.999 in the jackknife test. In the independent test, it has also achieved more than 97% sensitivity and 99% specificity. Similarly, in benchmarking with recent method CKSAAP_FormSite, the proposed predictor significantly outperformed in all the measures, particularly sensitivity by around 20%, specificity by nearly 30% and overall accuracy by more than 22%. These experimental results show that the proposed predForm-Site can be used as a complementary tool for the fast exploration of formylation sites. For convenience of the scientific community, predForm-Site has been deployed as an online tool, accessible at http://103.99.176.239:8080/predForm-Site.  相似文献   
33.
With the accelerated accumulation of genomic sequence data, there is a pressing need to develop computational methods and advanced bioinformatics infrastructure for reliable and large-scale protein annotation and biological knowledge discovery. The Protein Information Resource (PIR) provides an integrated public resource of protein informatics to support genomic and proteomic research. PIR produces the Protein Sequence Database of functionally annotated protein sequences. The annotation problems are addressed by a classification-driven and rule-based method with evidence attribution, coupled with an integrated knowledge base system being developed. The approach allows sensitive identification, consistent and rich annotation, and systematic detection of annotation errors, as well as distinction of experimentally verified and computationally predicted features. The knowledge base consists of two new databases, sequence analysis tools, and graphical interfaces. PIR-NREF, a non-redundant reference database, provides a timely and comprehensive collection of all protein sequences, totaling more than 1,000,000 entries. iProClass, an integrated database of protein family, function, and structure information, provides extensive value-added features for about 830,000 proteins with rich links to over 50 molecular databases. This paper describes our approach to protein functional annotation with case studies and examines common identification errors. It also illustrates that data integration in PIR supports exploration of protein relationships and may reveal protein functional associations beyond sequence homology.  相似文献   
34.
Molecular dynamics calculations of a mixed micelle composed of sodium dodecyl sulfate (SDS) and octaethylene glycol monododecyl ether (C12E8) were performed for six compositions (SDS/C12E8 = 100/0, 80/20, 60/40, 40/60, 20/80, and 0/100) to investigate the composition dependence of the mixed micelle structure and solubilization of cyclohexane, benzene, and phenol molecules by the micelle. The radial density distribution of the hydrophilic polyoxyethylene (POE) group of C12E8 as a function of distance from the micelle center is very sharp for micelles with high SDS content because the POE group captures a Na+ ion in solution and wraps around it to form a compact crown-ether-like complex. The hydrophobic dodecyl groups of SDS and C12E8 were separately distributed in the mixed micelle core. ΔG(r) evaluated for each solute showed that despite the structural changes of the micelle the binding strength of the solute molecules to the micelle did not change significantly. © 2019 Wiley Periodicals, Inc.  相似文献   
35.
在分析当前省属工科院校教育以能力为导向培养目标完成实施过程中遇到国际化困难问题的基础上,以青岛大学材料学科为例,提出了基于国际化产科教融合实训平台的教学模式改革举措,并经过实践验证证实其切实可行。包括:充分整合校内外材料学科整体资源,建立了国际化的产科教深度融合实训平台,构建了高效的国际化产科教深度融合协同育人实训平台动态管理运行机制;以实训平台为依托实现师资队伍、教学内容、教学模式、科研等全方位的国际化改革;基于国际化产教研融合实训平台的教学模式改革的实践收到显著成效,对全国省属高等院校理工学科专业建设国际化改革的推广有较好的示范作用。  相似文献   
36.
陈亚光 《化学教育》2019,40(4):30-33
元素无机化学是大学化学及相关专业无机化学课程的核心内容。如何教好、学好元素无机化学的知识一直是教学工作者研究的课题。为改变教学现状,提高教学效果,培养学生的逻辑思维和科学创新能力,提出一种整合元素无机化学知识的思路,即:以化合物类型为主线对元素无机化学知识进行系统化整合,并以氧化物部分为例加以说明。  相似文献   
37.
The model of regular solutions, that may be applied to binary alloys (e.g. Au?Pt, Si?Ge) has been compared to binary societies: blacks—non-blacks in the US, catholics—non-catholics, foreigners—German citizen. The excellent agreement of phase diagrams and intermarriage data encourages a calculation of the multicultural society by functions of thermodynamics: Solubility corresponds to integration, miscibility gap to segregation, free enthalpy to happiness and temperature to tolerance of a society. Only a high level of tolerance will integrate ghettos and lead to a peaceful multicultural society.  相似文献   
38.
All-atom molecular dynamics (MD) simulation has become a powerful research tool to investigate structural and dynamical properties of biological membranes and membrane proteins. The lipid structures of simple membrane systems in recent MD simulations are in good agreement with those obtained by experiments. However, for protein-membrane systems, the complexity of protein-lipid interactions makes investigation of lipid structure difficult. Although the area per lipid is one of the essential structural properties in membrane systems, the area in protein-membrane systems cannot be computed easily by conventional approaches like the Voronoi tessellation method. To overcome this limitation, we propose a new method combining the two-dimensional Voronoi tessellation and Monte Carlo integration methods. This approach computes individual surface areas of lipid molecules not only in bulk lipids but also in proximity to membrane proteins. We apply the method to all-atom MD trajectories of the sarcoplasmic reticulum Ca(2+)-pump and the SecY protein-conducting channel. The calculated lipid surface area is in agreement with experimental values and consistent with other structural parameters of lipid bilayers. We also observe changes in the average area per lipid induced by the conformational transition of the SecY channel. Our method is particularly useful for examining equilibration of lipids around membrane proteins and for analyzing the time course of protein-lipid interactions.  相似文献   
39.
The incorporation of explicit ions to mimic the effect of ionic strength or to neutralize the overall charge on a system in free energy calculations using molecular dynamics simulations is investigated. The difference in the free energy of hydration between two triosephosphate isomerase inhibitors calculated at five different ion concentrations is used as an example. We show that the free energy difference can be highly sensitive to the presence of explicit ions even in cases where the mutation itself does not involve a change in the overall charge. The effect is most significant if the molecule carries a net charge close to the site mutated. Furthermore, it is shown that the introduction of a small number of ions can lead to very severe sampling problems suggesting that in practical calculations convergence can best be achieved by incorporating either no counterions or by simulating at high ionic strength to ensure sufficient sampling of the ion distribution.  相似文献   
40.
The approach for the integration over a region covered by zero‐flux surface is described. This approach based on the surface triangulation technique is efficiently realized in a newly developed program TWOE . The elaborated method is tested on several atomic properties including the source function. TWOE results are compared with those produced by using well‐known existing programs. Absolute errors in computed atomic properties are shown to range usually from 10?6 to 10?5 au. The demonstrative examples prove that present realization has perfect convergence of atomic properties with increasing size of angular grid and allows to obtain highly accurate data even in the most difficult cases. It is believed that the developed program can be bridgehead that allows to implement atomic partitioning of any desired molecular property with high accuracy. © 2012 Wiley Periodicals, Inc.  相似文献   
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