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排序方式: 共有804条查询结果,搜索用时 125 毫秒
91.
92.
The pressure towards tighter or “seamless” integration of health information systems is a recurring issue with both practical
and analytical relevance. It taps into a discourse in the IS literature in general and organisation and management science
in particular. Unfortunately, the prevailing perception of integration in the IS literature is as a predominantly technical
issue. The CSCW literature, however, is attentive to the socio-technical aspects of integration. Building on this – but supplemented
with recent elaborations in science studies – we aim at exploring the unintended consequences of information systems integration.
A user-led perspective implies emphasising the tailoring to local needs based on in-depth studies of the micro practices.
We argue, however, that the condition for such an approach is radically undermined by politically motivated, regional changes
towards integration with implicated standardisation. Enforcing order in the form of standards across multiple local settings,
seemingly a prerequisite for tight integration, simultaneously produces disorder or additional work in other locations for
other users. Empirically, our study is based on a large, ongoing integration effort at the University hospital of Northern
Norway, specifically studying work practices and perceptions across multiple laboratories. 相似文献
93.
Gunnar Jacobson 《Datenschutz und Datensicherheit - DuD》2016,40(4):217-221
Digitale Zertifikate werden bereits in großem Umfang zur Verschlüsselung mit Desktop Clients wie Outlook eingesetzt. Damit ein Benutzer auch an all seinen Mobilgeräten verschlüsselte E-Mails lesen und an beliebige Empfänger verschlüsseln kann, müssen sein privater Schlüssel sowie die Zertifikate der Partner dort verfügbar sein. 相似文献
94.
95.
I. Lazoglu K. Buyukhatipoglu H. Kratz F. Klocke 《Machining Science and Technology》2013,17(2):157-179
In precision machining, due to the recent developments in cutting tools, machine tool structural rigidity and improved CNC controllers, hard turning is an emerging process as an alternative to some of the grinding processes by providing reductions in costs and cycle-times. In industrial environments, hard turning is established for geometry features of parts with low to medium requirements on part quality. Better understanding of cutting forces, stresses and temperature fields, temperature gradients created during the machining are very critical for achieving highest quality products and high productivity in feasible cycle times. To enlarge the capability profile of the hard turning process, this paper introduces prediction models of mechanical and thermal loads during turning of 51CrV4 with hardness of 68 HRC by a CBN tool. The shear flow stress, shear and friction angles are determined from the orthogonal cutting tests. Cutting force coefficients are determined from orthogonal to oblique transformations. Cutting forces, temperature field for the chip and tool are predicted and compared with experimental measurements. The experimental temperature measurements are conducted by the advanced hardware device FIRE-1 (Fiberoptic Ratio Pyrometer). 相似文献
96.
Amyloid beta peptide (Abeta) fibril formation is widely believed to be the causative event of Alzheimer's disease pathogenesis. Therapeutic approaches are therefore in development that target various sites in the production and aggregation of Abeta. Herein we present a high-throughput screening tool to generate novel hit compounds that block Abeta fibril formation. This tool is an application for our fibril model (Abeta(16-37)Y(20)K(22)K(24))(4), which is a covalent assembly of four Abeta fragments. With this tool, screening studies are complete within one hour, as opposed to days with native Abeta(1-40). A Z' factor of 0.84+/-0.03 was determined for fibril formation and inhibition, followed by the reporter molecule thioflavin T. Herein we also describe the analysis of a broad range of reported inhibitors and non-inhibitors of Abeta fibril formation to test the validity of the system. 相似文献
97.
The d-band model of Hammer and Nørskov (Nature 376:238, 1995 [3]) relating adsorption energies to the d-band position, and the adsorption energies to barriers in catalytic reactions, has been extremely successful in predicting reactivities and catalysts. In the present contribution we review recent combined experimental and theoretical work on chemical bond-formation at surfaces. We focus on the adsorbate and how the adsorbate electronic structure can be rehybridized through mixing with unoccupied states to generate the radical state, real or virtual, that can then form electron pairs with the metal d-states, as described by the d-band model. We discuss five important bonding situations: (i) atomic radical, (ii) diatomics with unsaturated π-systems (Blyholder model), (iii) unsaturated hydrocarbons (Dewar–Chatt–Duncanson model), (iv) lone–pair interactions, and (v) saturated hydrocarbons (physisorption). Where the d-band model predicts trends along the series of transition metals, the present work provides intuitive tools for predicting trends among different adsorbates. 相似文献
98.
The interaction of two antitumor ruthenium(III) complexes,-Na[trans-RuCl(4)(DMSO)(Im)] and Na[trans-RuCl(4)(DMSO)(Ind)]- with human serum apotransferrin (apoTf) was investigated through a number of spectroscopic techniques such as UV-Vis absorption, CD and (1)H NMR spectroscopy. Interestingly, the hydrolysis profiles of these complexes in a physiological buffer are markedly affected by the presence, in solution, of apoTf suggesting the occurrence of a specific interaction of their respective hydrolysis products with the protein. The formation of stable adducts with apotransferrin has been demonstrated by CD spectroscopy, and additional information obtained through (1)H NMR of the hyperfine shifted signals. The bound ruthenium(III) species may be detached from these adducts by addition of excess citrate at low pH. The behavior of the investigated ruthenium(III) complexes with apoTf is compared with that of the recently described and strictly related ru-im and ru-ind antitumour complexes, and discussed in the frame of general strategies of drug targeting. 相似文献
99.
Metal contamination at a wood preservation site: characterisation and experimental studies on remediation 总被引:2,自引:0,他引:2
Bhattacharya P Mukherjee AB Jacks G Nordqvist S 《The Science of the total environment》2002,290(1-3):165-180
The aim of this investigation was to determine the occurrence of As, Cu, Cr and Zn in the soil at an abandoned wood preservation unit and to examine some possible extractants for the contaminants in the soil. The mean As content of the contaminated surface soils (0-10 cm) was 186 mg kg(-1), where as the mean concentrations of Cu, Cr and Zn in soils from the contaminated area were 26, 29 and 91 mg kg(-1), respectively. The elevated As content in the mineral soils is related to adsorption of inorganic As phases in the fine grained fractions, which are characterised by large surface area and high positive surface charge under the current acidic conditions. Cu and Cr were found to be rather mobile, which is reflected in their lower abundance in soils and significant accumulation in sediments in the drainage leaving the area. The fine fraction of the soil (<0.125 mm) has an average metal content increased by nearly 34% as compared to the <2-mm fraction conventionally used for the analysis and assessment of soil contamination. The <2-mm fraction constitutes approximately 65% of the total weight while the fine fraction (<0.125 mm) constitutes approximately 10%. These facts, taken together, are essential for the choice of remediation measures. Oxalate solutions have been tested as extractants for soil remediation. Dark acid oxalate extraction dissolves the amorphous Al- and Fe-oxides and hydroxides and mobilises the adsorbed inorganic As species. Oxalate also acts as a ligand for the cationic heavy metals, releasing them from exchangeable sites. With a three-step sequential leaching, up to 98-99% of the metals could be removed. At lower concentrations and higher pH, the leaching decreased to approximately 70%. 相似文献
100.
Bahman Bohloli Bo Ronge Gunnar Gustafson 《Bulletin of Engineering Geology and the Environment》2002,61(1):43-47
Mechanical testing and ultrasonic measurements were used to establish the properties of metamorphic rocks in different directions
of the foliation plane. Tests were undertaken on 42 mm diameter specimens cored at right angles to the foliation of gneissic
rocks from southwest Sweden. Ultrasonic and tensile testing was carried out in three diametral directions and the data for
each direction were compared. Coefficients, failure load anisotropy and velocity anisotropy were obtained. An anisotropy coefficient
of 3% was detected by ultrasonic measurements, while the Brazilian tests indicated 15%. The study has shown that an anisotropy
coefficient of the foliation plane is present, albeit small.
Electronic Publication 相似文献