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排序方式: 共有248条查询结果,搜索用时 46 毫秒
1.
From may 1994 to may 1995, eight consecutive patients with symptomatic congenital ureteropelvic junction syndrome (UPJS) were treated by pyeloplasty as described by Anderson, Hynes and Küss by laparoscopic surgery. Three patients had a lower pole artery crossing the anterior surface of the junction and two had a giant renal pelvis. The mean operating time was 120 minutes (min: 90 min; max: 147 min) and the mean hospital stay in the absence of complications (one case) was 3.5 days (min: 1.5 day; max: 8 days). This one complication was due to a postoperative fistula resulting from a technical error requiring an additional fortnight in hospital. All the patients are evaluable at three months. All are asymptomatic and the radiological results showed frank improvement in seven out of eight cases, while the dynamic appearance was improved in the other case. UPJS can be treated by laparoscopic surgery according to proven surgical principles, provided it is performed in a perfectly equipped operating room, by a surgeon and operating team experienced in this type of surgery.  相似文献   
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Congenital deficiencies of protein S (PS) are associated with thrombophilia. Their characterization and classification have been hampered by the complex physiology of the protein C-protein S system and the poor standardization and reliability of laboratory assays. The free active form of protein S is usually determined by immunoassay using polyclonal antibodies in the plasma supernate after polyethyleneglycol (PEG) precipitation. A new one step ELISA using two monoclonal antibodies specific for distinct epitopes of the free form of protein S has been developed for the direct measurement of free PS in untreated plasma. We have tested two ELISA assays for free PS. One assay was based on the PEG precipitation (Asserachrom PS, Stago, Asnières, France) whereas the other was a one step ELISA assay (Asserachrom free PS, Stago). Values were obtained in 35 PS deficient patients recruited among 500 consecutive patients evaluated by the laboratory for diagnosis of congenital disorders of coagulation. Values were compared to those obtained in 50 patients with no PS deficiency matched for age and sex with the PS deficient patients as well as in 33 normal subjects and in 12 pregnant women. Strong correlation was found between the two tests (r = 0.81, p < 10(-5)) in the entire population (n = 130), as well as in the separate groups. The new one step ELISA was more accurate than the PEG free PS determination. Determination of PS activity and antigens allowed us to separate quantitative and qualitative deficiencies. Among the qualitative deficiencies, isolated decrease in PS activity was the most frequent defect observed (66%). This fact questions the substitution of PS activity assays by the one step antigenic free PS ELISA assay.  相似文献   
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Convenient for both biologists and MEMS designers, Polydimethylsiloxane (PDMS) polymer is intensively investigated for its biocompatibility, transparency, high resistance under plasma treatment, flexibility and resistance to high temperature. However, for microfluidic applications, the fabrication of PDMS circular channels is difficult to achieve except by wire moulding. In this article, we present a simple, fast and low-cost fabrication method which can be applied out of clean-room environment. It is based on the deposition of alginic acid sodium salt aqueous solution, enabling the formation of a liquid cylinder on the most hydrophilic part of a hydrophilic/hydrophobic patterned surface. We experimentally studied the interaction between liquid rivulets and surfaces presenting a contrast of wettability and/or a stepwise texture. Subsequent moulding of the half-cylinder of liquid produces round PDMS microfluidic channels. The optimal parameters for hydrophilic/hydrophobic patterns have then been applied to produce the roundest possible channels. The realisation of both straight channels 300–500 μm wide, 1 cm long and 75° tangent chord angle at best, and Y-shaped channels with the same dimensions and 55° TCA is demonstrated.  相似文献   
5.
Interactive visualization of volume models in standard mobile devices is a challenging present problem with increasing interest from new application fields like telemedicine. The complexity of present volume models in medical applications is continuously increasing, therefore increasing the gap between the available models and the rendering capabilities in low-end mobile clients. New and efficient rendering algorithms and interaction paradigms are required for these small platforms. In this paper, we propose a transfer function-aware compression and interaction scheme, for client-server architectures with visualization on standard mobile devices. The scheme is block-based, supporting adaptive ray-casting in the client. Our two-level ray-casting allows focusing on small details on targeted regions while keeping bounded memory requirements in the GPU of the client. Our approach includes a transfer function-aware compression scheme based on a local wavelet transformation, together with a bricking scheme that supports interactive inspection and levels of detail in the mobile device client. We also use a quantization technique that takes into account a perceptive metrics of the visual error. Our results show that we can have full interaction with high compression rates and with transmitted model sizes that can be of the order of a single photographic image.  相似文献   
6.
In this paper a wafer-level process is proposed to fully integrate carbon-based micro-supercapacitor onto silicon substrate. This process relies on the deposition of a paste containing carbon, PVDF and acetone into cavities etched in silicon. After electrolyte deposition in a controlled atmosphere, a wafer-level encapsulation is realized. Cyclic voltammetry performed on non-encapsulated micro-components showed specific energy of 257 mJ cm−2 for 336 μm deep cavities. The specific encapsulation process developed was tested separately and proved to be efficient in terms of resistance to organic electrolytes and mechanical strength.  相似文献   
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Ti, TiC, Al and AlN powders were mixed to synthesize Ti2Al(CxNy) (x + y < 1) solid solutions, Ti2AlCx (x < 1) and Ti2AlN‐related end‐members by hot isostatic pressing at 1400°C/80 MPa for 4 h. For the pure carbides, it is demonstrated that single‐phased samples can only be obtained when about 15% of substoichiometry on the carbon site is applied. Such a result likely implies that Ti2AlCx can only exist in a narrow range of carbon composition. Ti2AlN nitride can be synthesized with y = 1. Assuming that vacancy content varies linearly from 0 to 0.15 going from Ti2AlN to Ti2AlC0.85 in the solid solutions, element concentrations have been calculated to synthesize different solid solutions. Thus, it is demonstrated that single‐phased and fully dense Ti2Al(C0.23N0.71), Ti2Al(C0.45N0.45), and Ti2Al(C0.66N0.22) carbonitrides can be synthesized.  相似文献   
9.
Reviews the book, Memory, war and trauma by Nigel C. Hunt (see record 2010-17048-000). Hunt’s book presents a very different perspective on how memory, war, and trauma interface, drawing upon a variety of sources not frequently accessed by psychologists. He promotes an interdisciplinary approach to studying memory and war; however, rather than drawing upon the usual fields, such as biology or sociology, Dr. Hunt suggests that a careful examination of history and literature are also integral to developing a complete understanding of memory and war. This book is not designed for individuals unfamiliar with the field of trauma and war. Memory, war and trauma highlights the limitations of current empirical approaches to studying war trauma and presents a narrative methodology that he argues will better capture the unique individual experience of trauma. Hunt rightly demonstrates weaknesses of current methods, and suggests that the narrative method may be the solution to some of the problems with current methods. Though his argument is likely that the narrative method should supplement rather than replace current experimental method, one is left feeling that he believes current methods are wholly inadequate and his method is better. Despite this central weakness, this book will be a benefit to psychologists who study and treat individuals touched by war because it will encourage them to think beyond traditional approaches to research and treatment. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
10.
This paper describes a method to obtain a closed surface that approximates a general 3D data point set with nonuniform density. Aside from the positions of the initial data points, no other information is used. Particularly, neither the topological relations between the points nor the normal to the surface at the data points are needed. The reconstructed surface does not exactly interpolate the initial data points, but approximates them with a bounded maximum distance. The method allows one to reconstruct closed surfaces with arbitrary genus and closed surfaces with disconnected shells.  相似文献   
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