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961.
作为典型的智能嵌入式程序制备体制模式,在积累一定成效第三方应用程序人机交互式管理界面的基础上,具体保障合理认知活动下的安全可靠通信交流效果,这是运营商创设该类测试模块功能的核心指标任务。尽管目前传统手工测试的手段还比较普遍,大规模环境下的压力测试和系统循环式向导对比存在着长周期,低效率等问题,但智能化时代的技术格局效应,在满足实时监督和非侵入安定环境的前提下,提供不同结构的配备终端响应支持软件,可以高效满足测试效率的提升标准,保证终端平台的整体软件控制协调工作质量。 相似文献
962.
为自动检测出眼底图像中的视网膜内出血,从而构建基于眼底图像的糖尿病视网膜病变自动筛查系统,提出了基于多模板匹配的局部自适应区域生长法用以自动检测该病灶。首先,对眼底主要生理结构进行光谱特征分析,从而为不同分割目标选取合适的RGB通道;其次,利用HSV空间的亮度校正以及对比度受限自适应直方图均衡方法对眼底图像进行预处理;在此基础上利用设计好的多个模板对图像进行归一化互相关模板匹配获取该病灶候选区域;然后,从中去除视盘、血管以消除相关假阳,从而得到区域生长所需种子;最后,利用局部自适应区域生长法获取其精确轮廓,从而实现该病灶的准确检测。利用该算法对90幅不同颜色、不同亮度、不同质量、不同分辨率眼底图像进行该病灶的自动检测,实验结果表明:该算法能快速、有效地自动检测出眼底图像中的视网膜内出血,且算法稳定可靠,可满足临床需求。 相似文献
963.
The real-time (or life testing) soft-error rate (SER) measurement is an experimental reliability technique to determine the soft error sensitivity of a given component, circuit or system from the monitoring of a population of devices subjected to natural radiation and operating under nominal conditions. This review gives a survey over recent real-time SER experiments, conducted in altitude and/or underground, and investigating modern CMOS logic technologies, down to the 40 nm technological node. The review also includes our different contributions conducted during the last decade on the ASTEP Platform (Altitude Single Event Effects Test European Platform) and at the LSM facility (Underground Laboratory of Modane) to characterize soft error mechanisms in advanced static (SRAM) memories. Finally, the review discusses the specific advantages and limitations of this approach as well as its comparison with accelerated tests using intense particle beams or sources. 相似文献
964.
The microstructure and shear strength of the high-temperature Zn–4Al–3Mg, Zn–4Al–3Mg–7Sn, and Zn–4Al–3Mg–13Sn solder alloys were investigated in the temperature range of 25–200 °C. The results revealed that the shear yield stress (SYS) and ultimate shear strength (USS) of all three alloys decrease with increasing test temperature. The ternary base alloy showed higher strength levels up to 145 °C, above which all alloys behave similarly. The superiority of the ternary alloy is ascribed to the higher volume fraction of the fine α−η eutectic and eutectoid structures and the hard MgZn2 and Mg2Zn11 particles. Introduction of Sn into the base alloy, however, resulted in substantial decrease in the strength, due to the presence of the soft Sn that reduces the volume fraction of the eutectic structure and the hard second phase particles. Despite the weakening effects of Sn, the strength of quaternary alloys is still higher than those of the Zn–Sn and Pb–Sn high-temperature solders. 相似文献
965.
《Analytical letters》2012,45(8):1389-1400
Abstract Batch injection analysis (BIA) is a new non-flow technique involving the injection of microliter samples toward a nearby detector, immersed in a large-volume blank solution. This paper describes the characteristics and advantages of employing thermal sensing devices as detectors for BIA. Similar to analogous flow injection measurements, batch injection thermal analysis offers high speed, reproducibility and simplicity, while eliminating the need for pumps, valves and associated tubing. There is no observable carryover and the precision is typically 2% (RSD). The batch injection thermal analysis is illustrated for enzymatic reactions, as well as redox and acid-base reactions. 相似文献
966.
Amalia Martínez Daniela Balieiro Fernando Labbe 《Optics and Lasers in Engineering》2012,50(2):231-235
The combination (often referred to as phase-stepping profilometry, PSP) of the fringe projection technique and the phase-stepping method allowed us to retrieve topographic maps of cuticles isolated from the abaxial surface of leaves; these were in turn sampled from an apple tree (Malus domestica) of the variety Golden Delicious. The topographic maps enabled us to assess the natural features on the illuminated surface and also to detect the whole-field spatial variations in the thickness of the cuticle. Most of our attention was paid to retrieve the highly-resolved elevation information from the cuticle surface, which included the trace (in the order of tens of micrometers) left by ribs and veins. We expect that the PSP application for retrieving the cuticle topography will facilitate further studies on the dispersion and coverage of state-of-the-art agrochemical compounds meant to improve the defending properties of the cuticle. Methodological details are provided below. 相似文献
967.
The bulge test is a particularly convenient testing method for characterizing elastomers under biaxial loading. In addition, it is convenient to utilize this test for validating material models in simulation due to the heterogeneous strain field induced during inflation. During the bulge test the strain field for elastomers covers uniaxial tension at the border to pure shear and equibiaxial tension at the pole. Elastomeric materials exhibit a hyperelastic material behavior, with a dependency on temperature and loading rate. The temperature effect on the mechanical behavior during biaxial loading is considered in the present study. A bulge test setup combined with a temperature chamber is developed in order to characterize this effect, and an exemplary temperature dependent characterization of a poly(norbornene) elastomer is performed with this setup. The equibiaxial stress–strain curves measured at 60 °C, 20 °C and −20 °C are presented. 相似文献
968.
This paper presents the results of experiments carried out on mechanical wings undergoing active root flapping and pitching in the wind tunnel. The objective of the work is to investigate the effect of the pitch angle oscillations and wing profile on the aerodynamic forces generated by the wings. The experiments were repeated for a different reduced frequency, airspeed, flapping and pitching kinematics, geometric angle of attack and wing sections (one symmetric and two cambered airfoils). A specially designed mechanical flapper was used, modelled on large migrating birds. It is shown that, under pitch leading conditions, good thrust generation can be obtained at a wide range of Strouhal numbers if the pitch angle oscillation is adjusted accordingly. Consequently, high thrust was measured at both the lowest and highest tested Strouhal numbers. Furthermore, the work demonstrates that the aerodynamic forces can be sensitive to the Reynolds number, depending on the camber of the wings. Under pitch lagging conditions, where the effective angle of attack amplitude is highest, the symmetric wing was affected by the Reynolds number, generating less thrust at the lowest tested Reynolds value. In contrast, under pure flapping conditions, where the effective angle of attack amplitude was lower but still significant, it was the cambered wings that demonstrated Reynolds sensitivity. 相似文献
969.
Concentration of tracer at a producing well is a function of time and of the flow field that transports the tracer from one well to another. Small localized changes in the permeability and porosity fields result in small changes in the observed concentration history. Calculation of the effect of changes in the petrophysical parameter fields on observed concentration is an integral part of most approaches to solving the inverse problem, i.e. calculation of permeability and porosity fields that are consistent with observed tracer concentrations. This paper does not address the inverse problem directly, only the forward problem, but the results are presented as semi-analytic formulas which are intended to provide physical insight into the limitations of the inverse procedure. In particular, for a simple example of dipole flow between two wells in a nearly homogeneous infinite 2D porous medium, the width of the region of significant influence is shown to scale as d where is the dispersivity and d is half the interwell distance. Also, for fixed injection and production rates the influence on concentration of variation in porosity and in log-permeability are shown to be similar in magnitude. 相似文献
970.