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排序方式: 共有1256条查询结果,搜索用时 125 毫秒
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Alexander Shakhov Christian Reichenbach Daria Kondrashova Philipp Zeigermann Dirk Mehlhorn Prof. Dirk Enke Dr. Rustem Valiullin 《化学,工程师,技术》2013,85(11):1734-1741
Mesoporous glasses – the leaching products of phase‐separated alkali borosilicate glasses – are widely used in fundamental research and practical applications. In this work, the option to control their internal mesopore structure by varying the conditions of microphase separation has been studied. Structure and transport characterization of a family of nanoporous glasses obtained under different conditions has been performed using a combination of several experimental techniques, including gas adsorption, nuclear magnetic resonance cryoporometry and diffusometry. 相似文献
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Portable mobile code is often executed by a host virtual machine using just‐in‐time compilation. In this context, the compilation time in the host virtual machine is critical. This compilation time can be reduced if optimizations are performed ahead‐of‐time before distribution of the mobile code. Unfortunately, the portable nature of mobile code limits ahead‐of‐time optimizations to those that are machine‐independent. This work examines the effect of machine‐independent optimizations on the performance of mobile code applications. All experiments use the SafeTSA Format, a mobile code format that is based on Static Single Assignment Form (SSA Form). The experiments, which are performed on both the PowerPC and IA32 architectures, indicate that the effects of performing classical machine‐independent optimizations are—in fact—quite machine‐dependent. Nevertheless, the results demonstrate that applying such optimizations in a mobile code system can be beneficial. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
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Hal Philipp 《电子设计技术》2009,16(4):62-63,68
现今社会上很多人都频繁地接触到触摸屏。这种装置最常见于PDA和手机等手持设备和售票终端系统等应用,其中大部分都基于电阻性技术。电阻性技术采用一个柔性外层,其压触固定内层时,会产生电信号,然后转换为X-Y坐标位置。此外,还有其它两种常用技术:表面声波(SAW)和电容感测技术,不过,一直以来,由于成本和构建的限制,这两种技术都仅用在公用信息服务应用(Kiosk applications)中。 相似文献
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OBJECTIVE AND IMPORTANCE: Symptomatic cerebral vasospasm can occur after resection of tumors in or adjacent to the basal cisterns, causing delayed neurological deterioration. This potentially treatable condition may go unrecognized. Delay in its recognition will adversely affect the outcome of the patients. There has been a few cases of vasospasm after tumoral resection reported in the literature, mostly in adults. We report a case of vasospasm after resection of a third nerve schwannoma in a pediatric patient. This is the youngest patient reported to date with vasospasm after resection of a brain tumor. CLINICAL PRESENTATION: A six years old girl presented with sudden onset diplopia. Radiological work-up revealed a third nerve mass. She underwent a craniotomy for resection of her mass. Pathological findings were consistent with a third nerve schwannoma. One week postoperatively, her mental status deteriorated. A CT scan revealed a diffuse hypodense area involving the right frontal and temporal lobes in the middle cerebral artery distribution as well as the midbrain. The absence of these findings on the MRI imaging performed on the first postoperative day made us evoke a vascular etiology. A cerebral angiogram was performed and revealed vasospasm in the right internal carotid artery and in the right middle and posterior cerebral arteries. Hyperdynamic hypervolemic hemodilutional therapy was instituted. CONCLUSION: Delayed clinical deterioration from vasospasm is a potentially reversible condition, if recognized early. A high index of suspicion should be maintained in case delayed clinical deterioration occurs after surgery of tumors in the basal cisterns. Cerebral angiography will confirm the diagnosis. Early institution of hyperdynamic hypervolemic hemodilutional therapy and angioplasty may reverse the deficit and improve outcome. 相似文献
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C Van de Wiele J Philippé JP Van Haelst J Van Damme H Thierens GE Leroux-Roels RA Dierckx 《Canadian Metallurgical Quarterly》1997,38(9):1417-1421
The purpose of this study was to evaluate chemotaxis and its relationship to apoptosis in 99mTc-HMPAO-labeled lymphocytes. METHODS: Peripheral lymphocytes, obtained from 12 healthy volunteers using lymphoprep, were divided in three equal fractions. One fraction was used as the control, one was labeled with cold HMPAO and one was labeled with 1.5 mCi (55.5 Mbq) 99mTc-HMPAO. Chemotaxis of T-lymphocytes was measured by the Boyden microchamber technique (BMA) (n = 8) using human monocyte chemotactic protein-3 (MCP-3) as chemoattractans. A chemotactic index was calculated as the number of HMPAO and 99mTc-HMPAO-labeled cells that migrated towards the MCP-3 solution, divided by the number of nonlabeled migrated lymphocytes. Apoptosis evaluation (n = 10) of unlabeled, HMPAO-labeled and 99mTc-HMPAO-labeled cells was performed using flowcytometry (FCM) forward light scatter analysis, 900 light scatter analysis, fluorescein-isothiocyanate (FITC)-labeled Annexin V and dye exclusion of propidium iodide. RESULTS: Chemotaxis of 99mTc-HMPAO-labeled T-lymphocytes was found to be reduced by approximately 31% (migration index of 0.69) (p = 0.01) as compared to both unlabeled and HMPAO-labeled lymphocytes, both the latter showing no difference in migration index. Whereas the mean percentages apoptotic lymphocytes in the unlabeled, 18.5%, and HMPAO-labeled fraction, 16.6%, were more or less comparable (p = 0.1), the mean percentage apoptotic cells in the 99mTc-HMPAO-labeled fraction was 51.8%, yielding a difference of 33.3% between 99mTc-HMPAO-labeled and unlabeled cells (p = 0.003). The procentual concordance between apoptotic cells (33.3%) and chemotactic impaired cells (31%) in the 99mTc-HMPAO-labeled fraction may be explained by the formation of a rigid cytoskeleton early in the apoptotic process that may theoretically limit chemotaxis. CONCLUSION: Using the BMA, chemotaxis of 99mTc-HMPAO-labeled lymphocytes was found to be reduced by approximately 31%. Furthermore, the percentage apoptotic lymphocytes induced by irradiation after labeling with 99mTc-HMPAO concurs well with the percentage of chemotaxis impaired cells. 相似文献
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Philipp Gutruf Eike Zeller Sumeet Walia Hussein Nili Sharath Sriram Madhu Bhaskaran 《Small (Weinheim an der Bergstrasse, Germany)》2015,11(35):4532-4539
The concept of realizing electronic applications on elastically stretchable “skins” that conform to irregularly shaped surfaces is revolutionizing fundamental research into mechanics and materials that can enable high performance stretchable devices. The ability to operate electronic devices under various mechanically stressed states can provide a set of unique functionalities that are beyond the capabilities of conventional rigid electronics. Here, a distinctive microtectonic effect enabled oxygen‐deficient, nanopatterned zinc oxide (ZnO) thin films on an elastomeric substrate are introduced to realize large area, stretchable, transparent, and ultraportable sensors. The unique surface structures are exploited to create stretchable gas and ultraviolet light sensors, where the functional oxide itself is stretchable, both of which outperform their rigid counterparts under room temperature conditions. Nanoscale ZnO features are embedded in an elastomeric matrix function as tunable diffraction gratings, capable of sensing displacements with nanometre accuracy. These devices and the microtectonic oxide thin film approach show promise in enabling functional, transparent, and wearable electronics. 相似文献