全文获取类型
收费全文 | 1212篇 |
免费 | 75篇 |
国内免费 | 1篇 |
专业分类
电工技术 | 11篇 |
化学工业 | 542篇 |
金属工艺 | 12篇 |
机械仪表 | 24篇 |
建筑科学 | 32篇 |
矿业工程 | 1篇 |
能源动力 | 49篇 |
轻工业 | 206篇 |
水利工程 | 7篇 |
石油天然气 | 1篇 |
无线电 | 59篇 |
一般工业技术 | 199篇 |
冶金工业 | 55篇 |
原子能技术 | 4篇 |
自动化技术 | 86篇 |
出版年
2024年 | 3篇 |
2023年 | 29篇 |
2022年 | 84篇 |
2021年 | 103篇 |
2020年 | 34篇 |
2019年 | 40篇 |
2018年 | 56篇 |
2017年 | 46篇 |
2016年 | 53篇 |
2015年 | 45篇 |
2014年 | 48篇 |
2013年 | 68篇 |
2012年 | 59篇 |
2011年 | 86篇 |
2010年 | 73篇 |
2009年 | 49篇 |
2008年 | 77篇 |
2007年 | 64篇 |
2006年 | 46篇 |
2005年 | 24篇 |
2004年 | 21篇 |
2003年 | 26篇 |
2002年 | 21篇 |
2001年 | 13篇 |
2000年 | 14篇 |
1999年 | 12篇 |
1998年 | 4篇 |
1997年 | 8篇 |
1996年 | 9篇 |
1995年 | 6篇 |
1994年 | 7篇 |
1993年 | 5篇 |
1992年 | 5篇 |
1991年 | 4篇 |
1990年 | 4篇 |
1989年 | 4篇 |
1988年 | 2篇 |
1987年 | 2篇 |
1986年 | 2篇 |
1985年 | 3篇 |
1984年 | 3篇 |
1983年 | 2篇 |
1982年 | 2篇 |
1981年 | 2篇 |
1980年 | 2篇 |
1977年 | 6篇 |
1975年 | 3篇 |
1974年 | 2篇 |
1970年 | 2篇 |
1966年 | 2篇 |
排序方式: 共有1288条查询结果,搜索用时 15 毫秒
91.
Among various coating systems for industrial and engineering applications, glass and glass-ceramic coatings have advantages
of chemical inertness, high temperature stability and superior mechanical properties such as abrasion, impact etc as compared
to other coating materials applied by thermal spraying in its different forms viz. PVD, CVD, plasma, etc. Besides imparting
required functional properties such as heat, abrasion and corrosion resistance to suit particular end use requirements, the
glass and glass-ceramic coatings in general also provide good adherence, defect free surface and refractoriness.
Systematic studies covering the basic science of glass and glass-ceramic coatings, the functional properties required for
a particular end-use along with the various fields of application have been reviewed in this paper. 相似文献
92.
93.
Zdeněk Sobalík Kamil Jíša Dalibor Kaucký Alena Vondrová Zdeňka Tvarůžková Jana Nováková 《Catalysis Letters》2007,113(3-4):124-129
The decomposition of nitrous oxide was studied over Fe-ferrierite, Me-ferrierites and Fe/Me-ferrierites (Me: Pt, Rh and Ru).
Flow as well as batch experiments were carried out and showed a synergy between Fe and Me ions. Ions of noble metals in Fe-ferrierite
increased the catalytic activity in the sequence Pt < Rh ≅ Ru. Addition of NO substantially decreased the decomposition of
N2O over Rh/ferrierite and Ru/ferrierite, but not over bimetallic ferrierites. NO
x
species created during the decomposition of nitrous oxide alone as well as with addition of NO, and employment of nitrous
oxide labeled with 18O allowed us to assume a changing decomposition mechanism in the presence of Me ions in Fe-ferrierites. 相似文献
94.
Herrington Rachael L.; Mitchell Alexandra E.; Castellani Angela M.; Joseph Jana I.; Snyder Douglas K.; Gleaves David H. 《Canadian Metallurgical Quarterly》2008,20(4):341
Previous research has identified 2 broad components of distress in intimate relationships: overt conflict, or disharmony, and emotional distance, or disaffection. Using confirmatory factor analysis, the authors derived 2 broadband scales of disharmony and disaffection from the Marital Satisfaction Inventory-Revised (D. K. Snyder, 1997), building upon previous measures of these constructs (D. K. Snyder & Regts, 1982) derived from the original instrument. The new scales demonstrated high internal consistency and test-retest reliability, as well as discriminative validity and convergent validity with independent criteria of relationship functioning. Distinct distributions of these scales in community and clinical samples suggested their complementary role in research on intimate relationships and assessment of couples in treatment. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
95.
96.
97.
98.
Lubica Sobotova Jana Jurkovicova Ludmila Sevcikova 《The Science of the total environment》2010,408(6):1264-1270
Objective
The objective of our study was to investigate and evaluate the relationship between road traffic noise and cardiovascular risk.Methods
The study sample (n = 659; 36.9% male, 63.1% female university students, mean age 22.83 ± 1.58 years) included a group exposed to road traffic noise (n = 280, Leq,24 h = 67 ± 2 dB(A)) and a control group (n = 379, Leq,24 h = 58.7 ± 6 dB(A)). Subjective response was determined by a validated noise annoyance questionnaire. The ten year risk of developing a coronary heart disease event was quantified as an evaluation of cardiovascular risk (SCORE60, Framingham 10-year risk estimation and projection to the age of 60, relative risk SCORE chart).Results
Cardiovascular risk scores were significantly higher in the exposed group based on the Framingham scores projected to the age of 60, SCORE60 (AOR = 2.72 (95% CI = 1.21-6.15)) and the relative risk SCORE chart (AOR = 2.81 (1.46-5.41)).Conclusions
These findings highlight the association between road traffic noise and cardiovascular risk. 相似文献99.
Patwari Neal Croft Jessica Jana Suman Kasera Sneha K. 《Mobile Computing, IEEE Transactions on》2010,9(1):17-30
Secret keys can be generated and shared between two wireless nodes by measuring and encoding radio channel characteristics without ever revealing the secret key to an eavesdropper at a third location. This paper addresses bit extraction, i.e., the extraction of secret key bits from noisy radio channel measurements at two nodes such that the two secret keys reliably agree. Problems include 1) nonsimultaneous directional measurements, 2) correlated bit streams, and 3) low bit rate of secret key generation. This paper introduces high-rate uncorrelated bit extraction (HRUBE), a framework for interpolating, transforming for decorrelation, and encoding channel measurements using a multibit adaptive quantization scheme which allows multiple bits per component. We present an analysis of the probability of bit disagreement in generated secret keys, and we use experimental data to demonstrate the HRUBE scheme and to quantify its experimental performance. As two examples, the implemented HRUBE system can achieve 22 bits per second at a bit disagreement rate of 2.2 percent, or 10 bits per second at a bit disagreement rate of 0.54 percent. 相似文献
100.
The published data in the literature and the reported models on foam-bed reactors have been reanalyzed. It is observed that the models have been developed assuming negligible conversion in the storage section although the storage constitutes 65–85% of the total volume of liquid/slurry charged into the reactor. For confirmation of the reported information, in the present work, experiments have been performed in foam-bed and bubble column slurry reactors for carbonation of hydrated lime slurry using carbon-dioxide gas under identical conditions. A comparison of the relative performances of the two reactors has been made. Storage section is found to be the main section governing the performance of the foam-bed slurry reactor. New mathematical models have been developed for both the reactors. The model predictions agree well with the experimental data. 相似文献