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981.
Spirkl FM Kunz S Schweinberger FF Farnbacher AN Schröter R Heiz U 《The Review of scientific instruments》2012,83(1):013114
The separation of ultraviolet photoelectron spectroscopy (UPS) and metastable impact electron spectroscopy (MIES) is usually performed by a time-of-flight (ToF) separation using pre-set ToF for both types of signal. In this work, we present a new, improved ex situ signal separation method for the separation of MIES and UPS for every single measurement. Signal separation issues due to changes of system parameters can be overcome by changing the ToF separation and therefore allowing for the application of a wider range of measuring conditions. The method also enables to identify and achieve separation of the two signals without any time consuming calibration and the use of any special material for the calibration. Furthermore, changes made to the discharge source are described that enable to operate an existing MIES/UPS source over a broader range of conditions. This allows for tuning of the yield of UV photons and metastable rare gas atoms leading to an improved signal to noise ratio. First results of this improved setup are well in agreement with spectra reported in literature and show increased resolution and higher signal intensities for both MIE and UP spectra compared to the previous, non-optimized setup. 相似文献
982.
983.
An inverted fluorescence microscope was upgraded into a compact three-dimensional laser scanning microscope (LSM) of 65 x 62 x 48 cm dimensions by means of a fast kHz galvoscanner unit, a piezodriven z-stage, and a picosecond (ps) 50 MHz laser diode at 405 nm. In addition, compact turn-key near infrared femtosecond lasers have been employed to perform multiphoton fluorescence and second harmonic generation (SHG) microscopy. To expand the features of the compact LSM, a time-correlated single photon counting unit as well as a Sagnac interferometer have been added to realize fluorescence lifetime imaging (FLIM) and spectral imaging. Using this unique five-dimensional microscope, TauMap, single-photon excited (SPE), and two-photon excited (TPE) cellular fluorescence as well as intratissue autofluorescence of water plant leaves have been investigated with submicron spatial resolution, <270 ps temporal resolution, and 10 nm spectral resolution. 相似文献
984.
Ulrich Gossla 《Beton- und Stahlbetonbau》2006,101(2):94-102
Steel Fibre reinforced concrete Flat Slabs Steel fibre reinforced concrete is a proven and reliable material for slabs on grade of industrial floor systems. Since several years, steel fibre reinforced concrete with additional reinforcement bars is used for free suspended pile supported industrial floors. The load carrying behaviour under service loading conditions is similar to that of elevated flat slabs. Recently, concretes with high fluidity allow higher fibre dosages than before. A full scale loading test on a flat slab of 340 m2 at TREFILARBED in Bissen, Luxemburg has proven that elevated slab structures made of steel fibre reinforced concrete with 100 kg/m3 fibre content can compete with traditional reinforced concrete slabs by means of load carrying capacity as well as concerning cost effectiveness. This paper deals with the development of free suspended SFRC slabs based on the performed full scale tests. Formulas for the ultimate limit state design according to the yield line theory are presented. Design criteria at serviceability limit state are provided. 相似文献
985.
Ulrich SCHAFF 《生命科学仪器》2010,8(3):19-21
对原代人体嗜中性粒细胞的转染是很重要的,因为它实现了对人体发炎响应中通道的研究,而这在以前是很难实现的,原因在于培养嗜中性粒细胞很困难。通过这项研究,从细胞存活率及siRNA传递角度,研究者确立了最佳的嗜中性粒细胞转染的电穿孔条件。使用这些条件,可以进一步将该技术应用到包括干细胞在内的其他难以转染的原代细胞中。可以预见,这一领域将会在不久的将来蓬勃发展起来。 相似文献
986.
Nesterov A König K Felgenhauer T Lindenstruth V Trunk U Fernandez S Hausmann M Bischoff FR Breitling F Stadler V 《The Review of scientific instruments》2008,79(3):035106
We examined the high precision deposition of toner and polymer microparticles with a typical size of approximately 10 microm on electrode arrays with electrodes of 100 microm and below using custom-made microelectronic chips. Selective desorption of redundant particles was employed to obtain a given particle pattern from preadsorbed particle layers. Microparticle desorption was regulated by dielectrophoretic attracting forces generated by individual pixel electrodes, tangential detaching forces of an air flow, and adhesion forces on the microchip surface. A theoretical consideration of the acting forces showed that without pixel voltage, the tangential force applied for particle detachment exceeded the particle adhesion force. When the pixel voltage was switched on, however, the sum of attracting forces was larger than the tangential detaching force, which was crucial for desorption efficiency. In our experiments, appropriately large dielectrophoretic forces were achieved by applying high voltages of up to 100 V on the pixel electrodes. In addition, electrode geometries on the chip's surface as well as particle size influenced the desorption quality. We further demonstrated the compatibility of this procedure to complementary metal oxide semiconductor chip technology, which should allow for an easy technical implementation with respect to high-resolution microparticle deposition. 相似文献
987.
988.
Dr.Gerhard Wagner Dr.Ulrich Remmlinger Manfred Fischer 《传动技术(上海)》2008,22(1):3-12
CFT30是第一种将链传动应用于前置(横置)前驱、并配备有提高起步性能的变矩器的CVT。变速器能够传递现代6缸发动机310Nm的转矩。它采用全电子控制,比目前常用的4速自动变速器及刚开发出来的6速自动变速器性能更好、油耗更低。完美的换档感觉提高了驾驶舒适性。本文介绍了变速器系统、设计和主要部件。对CFT30如何解决燃油经济性、性能和舒适性作了详细的解释。同时给出了重要的部件试验和车辆试验结果。 相似文献
989.
Rawn CJ Leeman JR Ulrich SM Alford JE Phelps TJ Madden ME 《The Review of scientific instruments》2011,82(2):024501
A fiber optic-based distributed sensing system (DSS) has been integrated with a large volume (72 l) pressure vessel providing high spatial resolution, time-resolved, 3D measurement of hybrid temperature-strain (TS) values within experimental sediment-gas hydrate systems. Areas of gas hydrate formation (exothermic) and decomposition (endothermic) can be characterized through this proxy by time series analysis of discrete data points collected along the length of optical fibers placed within a sediment system. Data are visualized as an animation of TS values along the length of each fiber over time. Experiments conducted in the Seafloor Process Simulator at Oak Ridge National Laboratory clearly indicate hydrate formation and dissociation events at expected pressure-temperature conditions given the thermodynamics of the CH(4)-H(2)O system. The high spatial resolution achieved with fiber optic technology makes the DSS a useful tool for visualizing time-resolved formation and dissociation of gas hydrates in large-scale sediment experiments. 相似文献
990.