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991.
Aliaga DG Rosen PA Bekins DR 《IEEE transactions on visualization and computer graphics》2007,13(4):786-797
Interactive visualization of architecture provides a way to quickly visualize existing or novel buildings and structures. Such applications require both fast rendering and an effortless input regimen for creating and changing architecture using high-level editing operations that automatically fill in the necessary details. Procedural modeling and synthesis is a powerful paradigm that yields high data amplification and can be coupled with fast-rendering techniques to quickly generate plausible details of a scene without much or any user interaction. Previously, forward generating procedural methods have been proposed where a procedure is explicitly created to generate particular content. In this paper, we present our work in inverse procedural modeling of buildings and describe how to use an extracted repertoire of building grammars to facilitate the visualization and quick modification of architectural structures and buildings. We demonstrate an interactive application where the user draws simple building blocks and, using our system, can automatically complete the building "in the style of other buildings using view-dependent texture mapping or nonphotorealistic rendering techniques. Our system supports an arbitrary number of building grammars created from user subdivided building models and captured photographs. Using only edit, copy, and paste metaphors, the entire building styles can be altered and transferred from one building to another in a few operations, enhancing the ability to modify an existing architectural structure or to visualize a novel building in the style of the others. 相似文献
992.
Studies were made on the stability of NaOCl at 40°C in the presence of sodium alkanesulfonate or alkylarenesulfonate anionic
surfactants, and in the presence of a nonionic surfactant,N-octylpyrrolidinone. The results were compared with NaOCl stability in the absence of additives and in the presence of nonsurfactant
short-chain sodium alkylbenzenesulfonates. The data indicated that the rate of NaOCl loss is greatly dependent upon the pH
of the solution, even at alkaline pHs. At initial pHs below 11, in the absence of additive, there is significant disproportionation
of OCl− to ClO
3
−
, accompanied by decrease in the pH of the solution, within a period of several days. Even at an initial pH of 11.3, in the
presence of the surfactants investigated, there is significant disproportionation of OCl− and decrease in the pH of the solution in the first several days. When the initial pH of the solution is 13.5, there is no
significant decrease in pH of the solution for at least two months in the presence of the surfactants studied. NaOCl stability
in the presence of surfactant decreases in the order: sodium linear alkanesulfonate > sodium linear alkyldiphenylethersulfonate
> sodium linear alkylbenzenesulfonate >>N-octylpyrrolidinone. Stability was greater in the presence of linear alkylarenesulfonates than in the presence of branched
alkylarenesulfonates. It is suggested that the differences in stability observed are due to the greater ease of oxidation
of tertiary carbon atoms compared to primary or secondary atoms. 相似文献
993.
994.
为在敏捷制造中实现检验的自动化,分析敏捷制造中公差和表面质量的检验信息的需求,提出检验信息模型的功能,设计和开发了检验信息模型的IDEF0(Integration Definition for Function Modelling)模型. 相似文献
995.
996.
997.
Koop C.E. Mosher R. Kun L. Geiling J. Grigg E. Long S. Macedonia C. Merrell R.C. Satava R. Rosen J.M. 《IEEE engineering in medicine and biology magazine》2008,27(6):29-38
Health-care system reforms can change the structure of the current U.S. health-care system, from centralized large hospitals to a distributed, networked healthcare system. In our model, medical care is delivered locally in neighborhoods and individual homes, using computer technologies like telemedicine, to link patients and primary care providers to tertiary medical providers. This decentralization could reduce costs enough to provide all citizens with medical insurance coverage; it would benefit patients and providers; and as a dual-use system, it would better protect the country's resources and citizens in an event of biological terror or natural disasters. 相似文献
998.
Ofira Zloto Nachum Rosen Ari Leshno Mordechai Rosner 《Contact lens & anterior eye》2017,40(4):267-269
Purpose
To examine to the very long term prognosis (16 years in average) of pterygium surgery with superior or inferior conjunctival graft.Methods
Clinical data for patients that underwent pterygium surgery with conjunctival graft by two surgeons at the Goldschleger Eye Institute, Sheba Medical Center, Israel, between the years 1997–2001 were retrieved from medical records. For all the included patients, data about their eye examinations was summarized and a questionnaire about their eye history was done.Results
Twenty four patients were included in the study. Eleven with superior conjunctival flap (Group 1), and thirteen with inferior conjunctival graft (Group 2). In group 1, there was one surgery for recurrent pterygium, and two in group 2. In all cases the grafts were sutured and Mitomycin C was not used. No recurrence of pterygium was found in either group. No eye complications or side effects were found after sixteen years in average.Conclusions
After a very long follow-up of almost two decades there are no recurrences of pterygium or complications when using upper conjunctival flap or lower conjunctival graft during the surgery. It seems that lower graft is as good as upper flap for preventing recurrence of pterygium. Larger studies are required in order to confirm these results. 相似文献999.
1000.
Blood-brain barrier disruption is common in many neurological diseases. Matrix metalloproteinases are induced in brain injury and increase capillary permeability by attacking the extracellular matrix around cerebral capillaries. Other neutral proteases are also increased in sites of secondary injury, and may contribute to the proteolysis of the blood-brain barrier. Therefore, we studied capillary permeability and histological tissue damage after intracerebral injection of neutrophil elastase, cathepsin G, heparatinase and plasmin. Adult rats were injected intracerebrally with an enzyme. After 1, 4 or 24 h, measurements were made of brain uptake of a radiolabeled tracer, [14C]sucrose. Enzymes that significantly increased capillary permeability were injected into other rats for histological assessment of tissue damage. Elastase increased capillary permeability significantly when compared with controls; maximal damage was seen at 4 h. Plasmin produced smaller increases in permeability at 4 h, exerting its maximal effect on sucrose uptake at 24 h. Cathepsin G had a small effect at 4 h. Heparitinase had no effect. Histologic examination of elastase-injected brains at 24 h revealed multifocal perivascular and intraparenchymal acute hemorrhages accompanied by a polymorphonuclear cell infiltrate. Elastase-injected brains were microscopically similar to saline-injected brains at 1 and 4 h. Plasmin produced fibrinoid changes in the blood vessels at 24 h, coinciding with the maximal increase in capillary permeability. We conclude that neutrophil elastase attacks the capillary extracellular matrix, causing extensive hemorrhage, while plasmin leads to increased vascular permeability and fibrinoid necrosis of blood vessel walls. Differential effects of neutral proteases released secondary to injury could be important in both the acute changes in blood vessel permeability and long-term alterations in vessel structure. 相似文献