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排序方式: 共有851条查询结果,搜索用时 15 毫秒
71.
Ibrahim Burki Cristian Rivas Jeff Hurst Matt Weldon Henry Yeung Jimmy Price Patrick Lysaght P.Y.Hung Raj Jammy 《集成电路应用》2008,(7):36-38
量测平台的复杂性和光学原理上的局限性制约着测量系统的应用,直到真空紫外光谱反射仪的出现,这种状况才得到改变。 相似文献
72.
73.
Sex differences in spatial skills are sometimes attributed to sex differences in spatial experience. This hypothesis rests on two assumptions: Spatial experience typically differs with sex, and spatial experience has lasting effects on spatial cognition. We tested the latter assumption in a controlled experiment with wild-caught prairie voles (Microtus ochrogaster) and their spatially deprived, laboratory-reared, first-generation offspring; we found the assumption to be unjustified. Although major differences in spatial experience had no effect on maze performance, relatively small differences in motivation produced a significant difference in error rates. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
74.
To have market relevance and gain widespread market adoption, zero energy buildings (ZEBs) will need to be designed and constructed cost-effectively, and preferably without additional costs. An approach was developed to create low-energy buildings without additional construction costs such that it yielded innovation in building technology and integration by the market. A case study of the implementation of this method is presented to provide a data point that ZEBs can be built with zero cost increase. Documenting cost-control best practices and packaging those strategies for adoption by the commercial building sector will help make the business case for ZEBs for mainstream construction and promote market uptake of the innovative technologies and design approaches needed. The holistic implementation of cost-control strategies will enable ZEBs to be designed and constructed on a typical budget. The current state of ZEB economics is evaluated and a path forward is proposed for greater market penetration of ZEBs. By demonstrating how to combine ZEB technologies and design approaches into an overall efficiency package that can be implemented at minimal (zero, in certain cases) incremental capital cost, the domain of ZEB design and construction can be expanded from a niche market to the commercial construction mainstream. 相似文献
75.
在各种新型先进设备上实施协同式电路保护可有助于提高设备可靠性、减少元器件数量,并使其符合严格的安规要求。协同式方法能够帮助保护电源、继电器和螺线管,避免因线路故障或过载造成电流增大以及尖峰电压或暴露在稳态过压状态带来的危害。 相似文献
76.
77.
Matt Smith 《计算机应用文摘》2011,(5):18-19
电脑是一套组合在一起的复杂电子器件,它们发起疯来可真令人头疼。高手们往往可以快速解决问题,但对于普通用户来说,蓝屏死机的提示信息毫无用处。这就是为什么大部分人一碰到问题,就会狂给心目中的高手发短信:我的电脑蓝屏了怎么办?死机怎么办?不能启动怎么力? 相似文献
78.
Room-temperature solid-matrix luminescence was investigated for two model compounds pyrene and 1-hydroxypyrene from optically clear sugar glasses. Several glasses were investigated. Novel glasses were prepared for the first time from binary mixtures of sugars for spectroscopy. Glasses were prepared from glucose/xylose and glucose/maltose. The glucose/maltose gave a superior glass compared to glucose/xylose. The glucose/maltose glass gave the best room temperature phosphorescence (RTP) for pyrene compared to glasses of glucose and maltose without a heavy atom. The RTP was weak for both pyrene and 1-hydroxypyrene without a heavy atom in the glucose glass. The addition of a heavy atom (12% NaI) gave a 44-fold increase in RTP of pyrene and a 10-fold increase in the RTP of 1-hydroxypyrene. Room temperature fluorescence (RTF) of pyrene and 1-hydroxypyrene were easily observed from all the glass systems studied. However, the pyrene RTF intensity varied with the different sugar glass systems studied. Furthermore, a polymer, polyacrylic acid (PAA), was added to the sugar matrix at the level of 1% and 2% to improve the rigidity of the glass matrix. The observed phosphorescence was weak for pyrene at both the 1% and 2% PAA concentrations. A glass prepared with 2% PAA gave the strongest RTP for pyrene. Addition of 12% NaI with 1% polyacrylic acid did improve the RTP of pyrene but it was less than the RTP of pyrene from a glucose glass with 12% NaI by a factor of 2.7. A glucose glass with 12% NaI was the best system for RTP of pyrene. 相似文献
79.
Mike Spillane Ryan Schoch Matt Cooke Travis Harvey Mike Greenwood Richard Kreider Darryn S Willoughby 《Journal of the International Society of Sports Nutrition》2009,6(1):6-14
Numerous creatine formulations have been developed primarily to maximize creatine absorption. Creatine ethyl ester is alleged
to increase creatine bio-availability. This study examined how a seven-week supplementation regimen combined with resistance
training affected body composition, muscle mass, muscle strength and power, serum and muscle creatine levels, and serum creatinine
levels in 30 non-resistance-trained males. In a double-blind manner, participants were randomly assigned to a maltodextrose
placebo (PLA), creatine monohydrate (CRT), or creatine ethyl ester (CEE) group. The supplements were orally ingested at a
dose of 0.30 g/kg fat-free body mass (approximately 20 g/day) for five days followed by ingestion at 0.075 g/kg fat free mass
(approximately 5 g/day) for 42 days. Results showed significantly higher serum creatine concentrations in PLA (p = 0.007)
and CRT (p = 0.005) compared to CEE. Serum creatinine was greater in CEE compared to the PLA (p = 0.001) and CRT (p = 0.001)
and increased at days 6, 27, and 48. Total muscle creatine content was significantly higher in CRT (p = 0.026) and CEE (p
= 0.041) compared to PLA, with no differences between CRT and CEE. Significant changes over time were observed for body composition,
body water, muscle strength and power variables, but no significant differences were observed between groups. In conclusion,
when compared to creatine monohydrate, creatine ethyl ester was not as effective at increasing serum and muscle creatine levels
or in improving body composition, muscle mass, strength, and power. Therefore, the improvements in these variables can most
likely be attributed to the training protocol itself, rather than the supplementation regimen. 相似文献
80.
Abstract We discuss the role of Bose enhancement of the dipole matrix element in photoassociation, using stimulated Raman adiabatic passage as an example. In a non-degenerate gas the time scale for coherent optical transients tends to infinity in the thermodynamic limit, whereas Bose enhancement keeps this time scale finite in a condensate. Coherent transients are therefore absent in photoassociation of a thermal non-degenerate gas, but are feasible if the gas is a condensate. 相似文献