全文获取类型
收费全文 | 212篇 |
免费 | 2篇 |
国内免费 | 1篇 |
专业分类
电工技术 | 3篇 |
化学工业 | 36篇 |
金属工艺 | 4篇 |
机械仪表 | 4篇 |
建筑科学 | 6篇 |
能源动力 | 6篇 |
轻工业 | 7篇 |
无线电 | 26篇 |
一般工业技术 | 29篇 |
冶金工业 | 84篇 |
原子能技术 | 1篇 |
自动化技术 | 9篇 |
出版年
2023年 | 1篇 |
2021年 | 3篇 |
2020年 | 1篇 |
2017年 | 1篇 |
2016年 | 4篇 |
2015年 | 3篇 |
2013年 | 9篇 |
2012年 | 5篇 |
2011年 | 10篇 |
2010年 | 9篇 |
2009年 | 9篇 |
2008年 | 7篇 |
2007年 | 7篇 |
2006年 | 10篇 |
2005年 | 9篇 |
2004年 | 3篇 |
2003年 | 1篇 |
2002年 | 8篇 |
2001年 | 4篇 |
2000年 | 5篇 |
1999年 | 6篇 |
1998年 | 30篇 |
1997年 | 11篇 |
1996年 | 5篇 |
1995年 | 7篇 |
1994年 | 4篇 |
1993年 | 4篇 |
1992年 | 2篇 |
1991年 | 4篇 |
1990年 | 2篇 |
1989年 | 4篇 |
1988年 | 1篇 |
1987年 | 2篇 |
1986年 | 3篇 |
1985年 | 1篇 |
1983年 | 9篇 |
1982年 | 1篇 |
1981年 | 2篇 |
1980年 | 1篇 |
1979年 | 1篇 |
1978年 | 2篇 |
1976年 | 3篇 |
1967年 | 1篇 |
排序方式: 共有215条查询结果,搜索用时 46 毫秒
41.
Twenty-one cases of overuse injury to the iliac crest apophysis is presented. It can be a significant cause of disability to the adolescent middle and long distance runner. All cases resolved with 4 to 6 weeks of rest. 相似文献
42.
Eron Leonard D.; Huesmann L. Rowell; Brice Patrick; Fischer Paulette; Mermelstein Rebecca 《Canadian Metallurgical Quarterly》1983,19(1):71
Conducted a 3-yr longitudinal study with 2 large samples of elementary school youngsters overlapping in 1 grade (N?=?672, 607, and 505 for each successive year). It was thus possible to trace developmental trends from Grades 1 to 5 on the following variables: aggression, frequency of TV viewing, extent of violence viewed on TV, judged realism of TV programs, and preference for masculine, feminine, or neutral activities. Data support the theory that there is a sensitive period during which the effect of TV can be especially influential on children's behavior. Further, since the correlation between violence viewing and aggression tends to increase until age 10–21 yrs, a cumulative effect beyond the sensitive period is suggested. (11 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
43.
Ethical issues for the family therapist can be complex when treatment of the family involves several members whose needs are conflicting. Such techniques as encouraging ventilation of hostile feelings, forming alliances with particular family members, and requiring reluctant members to attend sessions raise important ethical questions. The principle of confidentiality is less clear when the entire family is in treatment. Systematic ethics training should include examination of the therapist's own values and biases, as well as issues of honesty and competency, and continuing education programs. (24 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
44.
DG Evans SP Guy N Thakker JG Armstrong C Dodd DR Davies C Babbs T Clancy T Warnes P Sloan 《Canadian Metallurgical Quarterly》1993,34(10):1389-1393
One case of non-penetrance of the familial adenomatous polyposis (FAP) gene at 59 years of age and late onset of polyps on endoscopy and biopsy in this and two other families is described. Screening protocols should include dental screening as well as indirect ophthalmoscopy and endoscopy to detect minimal manifestations of the gene. In the absence of a specific DNA predictive test, bowel screening should continue well beyond 30 years of age. 相似文献
45.
The repair of DNA damage protects the genome of the cell from the insults of cancer causing agents. This was originally demonstrated in individuals with the rare genetic disease, xeroderma pigmentosum, the prototype of cancer genes, and subsequently in the relationship of mismatch repair to colon cancer. Recent studies suggest that individuals with less dramatic reductions in the capacity to repair DNA damage are observed at polymorphic frequency and these individuals have an increased susceptibility to several types of cancer. Screening of individuals for DNA sequence variation in the exons of 9 DNA repair genes has resulted in identification of 15 different polymorphic amino acid substitution variants. Although the studies to relate these variants to reduced DNA repair capacity and cancer status have not been completed, the available information is sufficient to suggest that DNA repair genes should be incorporated into molecular epidemiology and cancer susceptibility studies. The availability of molecular epidemiology data presents exciting opportunities for refinement of risk estimation models and identification of individuals at increased risk of disease, with resultant opportunities for effective surveillance and early intervention and treatment. The opportunities to acquire susceptibility data are associated with possible perils for establishment of regulations for permissible exposures to carcinogenic agents and also stigmatization of 'at risk' individuals that may result in decreased access to employment opportunities and health care. 相似文献
46.
Glebov VY Sangster TC Stoeckl C Knauer JP Theobald W Marshall KL Shoup MJ Buczek T Cruz M Duffy T Romanofsky M Fox M Pruyne A Moran MJ Lerche RA McNaney J Kilkenny JD Eckart MJ Schneider D Munro D Stoeffl W Zacharias R Haslam JJ Clancy T Yeoman M Warwas D Horsfield CJ Bourgade JL Landoas O Disdier L Chandler GA Leeper RJ 《The Review of scientific instruments》2010,81(10):10D325
The National Ignition Facility (NIF) successfully completed its first inertial confinement fusion (ICF) campaign in 2009. A neutron time-of-flight (nTOF) system was part of the nuclear diagnostics used in this campaign. The nTOF technique has been used for decades on ICF facilities to infer the ion temperature of hot deuterium (D(2)) and deuterium-tritium (DT) plasmas based on the temporal Doppler broadening of the primary neutron peak. Once calibrated for absolute neutron sensitivity, the nTOF detectors can be used to measure the yield with high accuracy. The NIF nTOF system is designed to measure neutron yield and ion temperature over 11 orders of magnitude (from 10(8) to 10(19)), neutron bang time in DT implosions between 10(12) and 10(16), and to infer areal density for DT yields above 10(12). During the 2009 campaign, the three most sensitive neutron time-of-flight detectors were installed and used to measure the primary neutron yield and ion temperature from 25 high-convergence implosions using D(2) fuel. The OMEGA yield calibration of these detectors was successfully transferred to the NIF. 相似文献
47.
Raman spectral imaging has been widely used for extracting chemical information from biological specimens. One of the challenges is to cluster the chemical groups from the vast amount of hyperdimensional spectral imaging data so that functionally similar groups can be identified. In this paper, we present an approach that combines a differential wavelet-based data smoothing with a fuzzy clustering algorithm for the classification of Raman spectral images. The preprocessing of the spectral data is facilitated by decomposing them in the differential wavelet domain, where the discrimination of true spectral features and noise can be easily performed using a multi-scale pointwise product (MPP) criterion. This approach is applied to the classification of spectral data collected from adhesive/dentin interface specimens where the spectral data exhibit different signal-to-noise ratios. The proposed wavelet approach has been compared to several conventional noise-removal algorithms. 相似文献
48.
The development of cognitive skills and gains in academic school readiness for children from low-income families. 总被引:1,自引:0,他引:1
Welsh Janet A.; Nix Robert L.; Blair Clancy; Bierman Karen L.; Nelson Keith E. 《Canadian Metallurgical Quarterly》2010,102(1):43
This study examined developmental associations between growth in domain-general cognitive processes (working memory and attention control) and growth in domain-specific skills (emergent literacy and numeracy) across the prekindergarten year and their relative contributions to kindergarten reading and math achievement. One hundred sixty-four Head Start children (44% African American or Latino; 57% female) were followed longitudinally. Path analyses revealed that working memory and attention control predicted growth in emergent literacy and numeracy skills during the prekindergarten year and that growth in these domain-general cognitive skills made unique contributions to the prediction of kindergarten math and reading achievement, controlling for growth in domain-specific skills. These findings extend research highlighting the importance of working memory and attention control for academic learning, demonstrating the effects in early childhood, prior to school entry. Implications of these findings for prekindergarten programs are discussed, particularly those designed to reduce the school readiness gaps associated with socioeconomic disadvantage. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
49.
Kristin Yaehne Amy Tekrony Aisling Clancy Yiota Gregoriou John Walker Kwin Dean Trinh Nguyen Amber Doiron Kristina Rinker Xiao Yu Jiang Sarah Childs David Cramb 《Small (Weinheim an der Bergstrasse, Germany)》2013,9(18):3118-3127
Nanoparticles are increasingly used in medical applications such as drug delivery, imaging, and biodiagnostics, particularly for cancer. The design of nanoparticles for tumor delivery has been largely empirical, owing to a lack of quantitative data on angiogenic tissue sequestration. Using fluorescence correlation spectroscopy, the deposition rate constants of nanoparticles into angiogenic blood vessel tissue are determined. It is shown that deposition is dependent on surface charge. Moreover, the size dependency strongly suggests that nanoparticles are taken up by a passive mechanism that depends largely on geometry. These findings imply that it is possible to tune nanoparticle pharmacokinetics simply by adjusting nanoparticle size. 相似文献
50.
A. Turlapov J. Kinast B. Clancy Le Luo J. Joseph J. E. Thomas 《Journal of Low Temperature Physics》2008,150(3-4):567-576
We use all-optical methods to produce a highly-degenerate Fermi gas of spin-1/2 6Li atoms. A magnetic field tunes the gas near a collisional (Feshbach) resonance, producing strong interactions between spin-up
and spin-down atoms. We have measured properties of a breathing mode over a wide range of temperatures. As the temperature
is increased from below the superfluid transition to above, the frequency of the mode is always close to the hydrodynamic
value, while the damping rate increases. A complete explanation of both the frequency and the damping rate in the normal collisional
regime has not been achieved. Our measurements of the damping rate as a function of the energy of the gas are used to estimate
an upper bound on the viscosity. Using our new measurements of the entropy of the gas, we estimate the ratio of the shear
viscosity to the entropy density and compare the result with a recent string theory conjecture for the minimum viscosity of
a perfect quantum fluid.
相似文献