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101.
Schlomer Gabriel L.; Del Giudice Marco; Ellis Bruce J. 《Canadian Metallurgical Quarterly》2011,118(3):496
Decades of research demonstrate that conflict shapes and permeates a broad range of family processes. In the current article, we argue that greater insight, integration of knowledge, and empirical achievement in the study of family conflict can be realized by utilizing a powerful theory from evolutionary biology that is barely known within psychology: parent–offspring conflict theory (POCT). In the current article, we articulate POCT for psychological scientists, extend its scope by connecting it to the broader framework of life history theory, and draw out its implications for understanding conflict within human families. We specifically apply POCT to 2 instances of early mother–offspring interaction (prenatal conflict and weaning conflict); discuss the effects of genetic relatedness on behavioral conflict between parents, children, and their siblings; review the emerging literature on parent–offspring conflict over the choice of mates and spouses; and examine parent–offspring conflict from the perspective of imprinted genes. This review demonstrates the utility of POCT, not only for explaining what is known about conflict within families but also for generating novel hypotheses, suggesting new lines of research, and moving us toward the “big picture” by integrating across biological and psychological domains of knowledge. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
102.
John P. Greene Guy SavardRichard C. Pardo Samuel I. BakerAnthony F. Levand Jr. Bruce J. Zabransky 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2011,655(1):21-23
The Californium Rare Ion Breeder Upgrade (CARIBU) project was conceived to provide neutron rich beams originating from the 3% fission decay branch of a 252Cf source to be accelerated by the Argonne Tandem Linear Accelerator System (ATLAS). This 1Ci 252Cf source will be housed in a movable shielded cask, from which it can be directly transferred into a large helium gas stopper cell. Within the gas stopper, the CARIBU 252Cf source is positioned behind an aluminum degrader foil where the radioactive recoils of interest lose most of their energy before being stopped in the helium gas. To stop recoils over the full fission mass range effectively, three degraders of increasing thickness are required, one to cover the light fission peak and two for the isotopes in the heavy fission peak.The geometry of the source within the gas cell would ideally require a hemispherically shaped degrader foil for uniform energy loss of the fission products. The fabrication of a thin foil of such a shape proved to be exceedingly difficult and, therefore, a compromise “top hat” arrangement was designed. In addition, the ultra-high vacuum (UHV) environment necessary for the gas cell to function properly prevented the use of any epoxy due to vacuum outgassing. Handling, assembling of the foils and mounting must be done under clean room conditions. Details of early attempts at producing these foils as well as handling and mounting will be discussed. 相似文献
103.
M.L. Lombardi A. FavalliJ.M. Goda K.D. IanakievC.E. Moss 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2011,652(1):112-115
A flux monitor diode is being explored as an option for measurement of the output of an X-ray tube that is used for active transmission measurements on a pipe containing UF6 gas. The measured flux can be used to correct for any instabilities in the X-ray tube or the high voltage power supply. For this measurement, we are using a silicon junction p-n photodiode, model AXUV100GX, developed by International Radiation Detectors, Inc. (IRD, Inc.). This diode has a silicon thickness of 104 μ and a thin (3-7 nm) silicon dioxide junction passivating, protective entrance window. These diodes have been extensively tested for radiation hardness in the UV range. However, we intend to operate mainly in the 10-40 keV X-ray region. We are performing radiation hardness testing over this energy range, with the energy spectrum that would pass through the diode during normal operation. A long-term measurement was performed at a high flux, which simulated over 80 years of operation. No significant degradation was seen over this time. Fluctuations were found to be within the 0.1% operationally acceptable error range. After irradiation, an I-V characterization showed a temporary irradiation effect which decayed over time. This effect is small because we operate the diode without external bias. 相似文献
104.
105.
The objective of the current investigation is to characterize the dynamic strain aging (DSA) behavior in alloys 800H and 690. Constant extension rate tests were conducted at strain rates in the range of 10?4 s?1 to 10?7?s?1and temperatures between 295?K and 673?K (22?°C and 400?°C), in an argon atmosphere. Maps for the occurrence of serrated flow as a function of strain rate and temperature were built for both alloys. The enthalpy of serrated flow appearance of alloy 800H was found to be 1.07?±?0.30?eV. 相似文献
106.
D. M. Pickup S. P. Valappil R. M. Moss H. L. Twyman P. Guerry M. E. Smith M. Wilson J. C. Knowles R. J. Newport 《Journal of Materials Science》2009,44(7):1858-1867
A sol–gel preparation of Ga-doped phosphate-based glass with potential application in antimicrobial devices has been developed.
Samples of composition (CaO)0.30(Na2O)0.20−x
(Ga2O3)
x
(P2O5)0.50 where x = 0 and 0.03 were prepared, and the structure and properties of the gallium-doped sample compared with those of the sample
containing no gallium. Analysis of the 31P MAS NMR data demonstrated that addition of gallium to the sol–gel reaction increases the connectivity of the phosphate network
at the expense of hydroxyl groups. This premise is supported by the results of the elemental analysis, which showed that the
gallium-free sample contains significantly more hydrogen and by FTIR spectroscopy, which revealed a higher concentration of
–OH groups in that sample. Ga K-edge extended X-ray absorption fine structure and X-ray absorption near-edge structure data
revealed that the gallium ions are coordinated by six oxygen atoms. In agreement with the X-ray absorption data, the high-energy
XRD results also suggest that the Ga3+ ions are octahedrally coordinated with respect to oxygen. Antimicrobial studies demonstrated that the sample containing Ga3+ ions had significant activity against Staphylococcus aureus compared to the control. 相似文献
107.
108.
109.
Bruce Diamond 《电子产品世界》2006,(16):23-24
近几年,无论是手机代表的无线移动网络及其基础设施,还是以蓝牙(Bluetooth)、无线局域网(WLAN)、Zigbee等长、短距离的无线通信技术,或者是WiMax、RFID等面向特定应用的专门技术,给人们带来了种种方便,也在悄悄改变着产业的格局.作为各种无线技术基础的RF技术,也在不断吸纳新技术、新设计,以满足系统对于更大数据传输量、更低的功耗和成本要求、更苛刻的信号可靠性要求等挑战.从另一侧面看,由于RF技术固有的较高门坎,并非一些新手力所能及,虽然半导体产业链以厂商数量众多著称,但RF技术供应商则相对较少. 相似文献
110.
Gel permeation chromatography with application of the universal calibration concept was found to be a rapid and effective method for quantification of extrusion-induced starch fragmentation. This method (Timpa. J.D., J. Agr. Food Chem. 39 (1991), 270–275) employs dimethyl acetamide (DMAC) with lithium chloride to solubilize samples and automated gel permeation chromatography for fractionation. Instrumentation was equipped with a viscometer and refractometer, data was interpreted by application of the universal calibration concept. These results confirm that the largest starch molecules in corn meal (107 to 108 Daltons) were slightly prone to fragmentation. Fragments produced were primarily in the weight range of 104–107 Daltons. In addition, some smaller fragments (ranging between 5,000 and 7.500) were also generated by extrusion. 相似文献