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排序方式: 共有914条查询结果,搜索用时 281 毫秒
761.
对曹雪芹文学思想的研究,目前学术界还是一片空白,本文从《红楼梦》原著去探讨曹雪芹的文学思想,认为作品体现了作者四个方面的文学思想,一是对“诗言志”传统的继承和发扬,二是对比兴寄托手法的运用和拓展,三是对虚实相生,有无相成艺术创作原则的把握,四是对“意境”的营建,对它们进行认真的总结和仔细的研究,和对作品本身的研究一样,同样具有十分重要的意义。  相似文献   
762.
This paper presents an experimental validation of the use of the virtual fields method to identify the elasto-plastic behaviour of an iron specimen from full-field measurements with the grid method and a simple heterogeneous test configuration. The experimental procedure is carefully detailed since it is of primary importance to obtain good identification results. In particular, the use of two back-to-back cameras has proved essential to eliminate out-of-plane effects. Then, the procedure for extracting the elastic parameters and the parameters of a Voce’s hardening model using the virtual fields method is presented. The results are very convincing and encouraging for future developments using more complex test geometries leading to fully multi-axial stress states. It is a first step towards the development of such inverse procedures as an alternative to difficult and costly methods involving homogeneous tests using multi-axial testing machines.  相似文献   
763.
The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is responsible for the COVID-19 which has infected millions of people worldwide. The main protease of SARS-CoV-2 (MPro) has been recognized as a key target for the development of antiviral compounds. Taking advantage of the X-ray crystal complex with reversible covalent inhibitors interacting with the catalytic cysteine 145 (Cys145), we explored flexible docking studies to select alternative compounds able to target this residue as covalent inhibitors. First, docking studies of three known electrophilic compounds led to results consistent with co-crystallized data validating the method for SARS-CoV-2 MPro covalent inhibition. Then, libraries of soft electrophiles (overall 41 757 compounds) were submitted to docking-based virtual screening resulting in the identification of 17 molecules having their electrophilic group close to the Cys145 residue. We also investigated flexible docking studies of a focused approved covalent drugs library including 32 compounds with various electrophilic functional groups. Among them, the calculations resulted in the identification of four compounds, namely dimethylfumarate, fosfomycin, ibrutinib and saxagliptin, able first, to bind to the active site of the protein and second, to form a covalent bond with the catalytic cysteine.  相似文献   
764.
Multidrug resistance (MDR) is one of the serious problems in cancer research that causes failure in chemotherapy. Chromene-based compounds have been proven to be the novel anti-MDR agents for inhibiting proliferation of tumor cells through tubulin polymerization inhibition of by binding at the colchicine binding site. In this study, we screened a chromene-based database of small molecules using physicochemical, ADMET properties and molecular docking to identify potential hit compounds. In order to validate our hit compounds, molecular dynamics simulations and related analysis were carried out and the results suggest that our hit compounds (PubChem CIDs: 16814409, 17594471, 57367244 and 69899719) can prove to be potential inhibitors of tubulin. The in silico results show that the present hits, like colchicine, effectively suppressed the dynamic instability of microtubules and induced microtubule-depolymerization and cell cycle arrest.  相似文献   
765.
Heat shock protein 70 is an effective anticancer target as it influences many signaling pathways. Hence the study investigated the important pharmacophore feature required for ATPase inhibitors of HSP70 by generating a ligand based pharmacophore model followed by virtual based screening and subsequent validation by molecular docking in Discovery studio V4.0. The most extrapolative pharmacophore model (hypotheses 8) consisted of four hydrogen bond acceptors. Further validation by external test set prediction identified 200 hits from Mini Maybridge, Drug Diverse, SCPDB compounds and Phytochemicals. Consequently, the screened compounds were refined by rule of five, ADMET and molecular docking to retain the best competitive hits. Finally Phytochemical compounds Muricatetrocin B, Diacetylphiladelphicalactone C, Eleutheroside B and 5-(3-{[1-(benzylsulfonyl)piperidin-4-yl]amino}phenyl)- 4-bromo-3-(carboxymethoxy)thiophene-2-carboxylic acid were obtained as leads to inhibit the ATPase activity of HSP70 in our findings and thus can be proposed for further in vitro and in vivo evaluation.  相似文献   
766.
为了有效解决化学化工类实验教学无法或者难以实现的教学过程问题,组建了黑龙江大学化学化工虚拟仿真实验教学中心,搭建了辅助虚拟实验教学和管理于一体的开放共享的虚拟仿真信息化网络平台,设计开发了系列化工、制药、仪器类虚拟仿真实验教学项目,开展理论课+线下实验课+虚拟仿真实验+慕课四维课程体系建设,期望提升本科一流专业和拔尖人才试验班建设以及本科人才培养,为提高学校本科教学质量提供有力的保障。  相似文献   
767.
胡延平  孙哲  张岩 《应用声学》2015,23(10):71-71
针对船舶电装生产设计中电缆敷设设计复杂繁琐,效率低下的问题,结合实际电缆敷设设计的流程,开发了基于AutoCAD二次开发的船舶电缆虚拟敷设仿真平台。重点对虚拟敷设通道数学模型的建立、交互式图形敷设方式的设计、带限制条件的最短路径算法的实现和电缆通道的仿真进行了详细阐述。电缆虚拟敷设平台的开发已经完成,初步实现了船舶电缆的虚拟敷设。该平台为电装设计人员提供了一种直观,动态的敷设设计方式,简化了电缆敷设设计过程,提高了敷设设计的效率和质量,同时节省了电缆用量。  相似文献   
768.
针对天线参数测试过程及测试要求,分析在天线参数测试中的主要问题,研究实际测试过程中环境因素对天线参数测量结果的影响,提出了一种基于虚拟仪器技术的远场天线性能参数自动测试系统的设计方案,详细阐述了该方案的系统组成部分与工作原理,包括矢量网络分析仪、天线测试转台与吊杆的控制原理以及数据采集的时序设计,结合Matlab实现了对影响因素的误差补偿与天线性能参数的测试计算方法,利用数据库技术实现天线测试数据的存储、读取与报告打印,通过现场测试试验验证了该方案的可靠性与可行性。  相似文献   
769.
针对LabWindows/CVI与S7-300 PLC通过MPI、IE以及OPC 3种通信方式建立连接及数据通信的应用场合和具体实现方法进行了研究,具有很好的工程应用价值,并依次完成了3种通信方式下LabWindows/CVI对西门子CPU 314C-2DP跑马灯程序的实时监控实验。实验证明3种数据通信方式稳定可靠,可以根据不同实际测控系统需求选择使用。  相似文献   
770.
采用3DSMax8.0软件,配合Vrp7.0制作虚拟现实平台,设计一套基于计算机虚拟现实技术的古建筑虚拟复原系统实现方案,完成对广西三江县程阳风雨桥数字重建过程,给出风雨桥的数字重建流程与具体的计算机虚拟重建的步骤,为文化遗产的数字化复原和保护提供可靠的技术支撑.  相似文献   
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