全文获取类型
收费全文 | 271篇 |
免费 | 5篇 |
专业分类
电工技术 | 11篇 |
化学工业 | 45篇 |
金属工艺 | 7篇 |
机械仪表 | 6篇 |
建筑科学 | 5篇 |
矿业工程 | 1篇 |
能源动力 | 11篇 |
轻工业 | 21篇 |
无线电 | 19篇 |
一般工业技术 | 19篇 |
冶金工业 | 99篇 |
原子能技术 | 7篇 |
自动化技术 | 25篇 |
出版年
2018年 | 2篇 |
2017年 | 3篇 |
2016年 | 3篇 |
2015年 | 3篇 |
2014年 | 3篇 |
2013年 | 8篇 |
2012年 | 3篇 |
2011年 | 8篇 |
2010年 | 12篇 |
2009年 | 9篇 |
2008年 | 6篇 |
2007年 | 7篇 |
2006年 | 2篇 |
2005年 | 7篇 |
2004年 | 7篇 |
2003年 | 8篇 |
2002年 | 3篇 |
2001年 | 6篇 |
2000年 | 5篇 |
1999年 | 11篇 |
1998年 | 16篇 |
1997年 | 10篇 |
1996年 | 13篇 |
1994年 | 8篇 |
1993年 | 3篇 |
1991年 | 2篇 |
1990年 | 3篇 |
1989年 | 6篇 |
1988年 | 5篇 |
1987年 | 5篇 |
1986年 | 4篇 |
1985年 | 4篇 |
1984年 | 5篇 |
1982年 | 3篇 |
1981年 | 3篇 |
1980年 | 8篇 |
1979年 | 2篇 |
1978年 | 3篇 |
1977年 | 5篇 |
1976年 | 10篇 |
1974年 | 3篇 |
1973年 | 5篇 |
1971年 | 4篇 |
1969年 | 2篇 |
1968年 | 2篇 |
1963年 | 5篇 |
1962年 | 3篇 |
1961年 | 3篇 |
1948年 | 1篇 |
1944年 | 1篇 |
排序方式: 共有276条查询结果,搜索用时 46 毫秒
1.
Sphingolipid metabolism and cell growth regulation 总被引:2,自引:0,他引:2
2.
One of the problems with insider threat research is the lack of a complete 360° view of an insider threat dataset due to inadequate experimental design. This has prevented us from modeling a computational system to protect against insider threat situations. This paper provides a contemporary methodological approach for using online games to simulate insider betrayal for predictive behavioral research. The Leader’s Dilemma Game simulates an insider betrayal scenario for analyzing organizational trust relationships, providing an opportunity to examine the trustworthiness of focal individuals, as measured by humans as sensors engaging in computer-mediated communication. This experimental design provides a window into trustworthiness attribution that can generate a rigorous and relevant behavioral dataset, and contributes to building a cyber laboratory that advances future insider threat study. 相似文献
3.
DW Morck JK Merrill BE Thorlakson ME Olson LV Tonkinson JW Costerton 《Canadian Metallurgical Quarterly》1993,202(2):273-277
The prophylactic administration of injectable tilmicosin for pneumonia in weaned beef calves was investigated in 1,806 animals. Comparisons were made among calves receiving an "on-arrival" injection of tilmicosin, calves receiving a single injection of long-acting oxytetracycline, and calves receiving no prophylaxis. Morbidity and mortality attributable to pneumonia, morbidity and mortality attributable to all causes, and case fatality were significantly lower in the group of calves that received tilmicosin, compared with calves that received long-acting oxytetracycline and calves that received no prophylactic antibiotic. Mean time to initial pneumonia treatment was significantly extended in calves that received prophylaxis, compared with those that received no antibiotic on arrival at the feedlot. Calves that received tilmicosin gained significantly more weight than calves that received oxytetracycline. Calves that were not treated for pneumonia during the trial period gained significantly more weight than did those calves that were treated for pneumonia regardless of experimental group. The majority of mortalities were attributable to fibrinous pneumonia (31/34). Important bacterial isolates (Pasteurella spp, Haemophilus somnus, Actinomyces pyogenes) obtained at necropsy did not have resistance to tilmicosin in association with administration of tilmicosin as prophylaxis for pneumonia. However, bacterial resistance to trimethoprim/sulfonamide and to oxytetracycline were commonly found in these postmortem isolates. 相似文献
4.
Differential effects of air conditioning type on residential endotoxin levels in a semi‐arid climate
下载免费PDF全文
![点击此处可从《Indoor air》网站下载免费的PDF全文](/ch/ext_images/free.gif)
J. D. Johnston B. A. Kruman M. C. Nelson R. M. Merrill R. J. Graul T. G. Hoybjerg S. C. Tuttle S. J. Myers R. B. Cook K. S. Weber 《Indoor air》2017,27(5):946-954
Residential endotoxin exposure is associated with protective and pathogenic health outcomes. Evaporative coolers, an energy‐efficient type of air conditioner used in dry climates, are a potential source of indoor endotoxins; however, this association is largely unstudied. We collected settled dust biannually from four locations in homes with evaporative coolers (n=18) and central air conditioners (n=22) in Utah County, Utah (USA), during winter (Jan‐Apr) and summer (Aug‐Sept), 2014. Dust samples (n=281) were analyzed by the Limulus amebocyte lysate test. Housing factors were measured by survey, and indoor temperature and relative humidity measures were collected during both seasons. Endotoxin concentrations (EU/mg) were significantly higher in homes with evaporative coolers from mattress and bedroom floor samples during both seasons. Endotoxin surface loads (EU/m2) were significantly higher in homes with evaporative coolers from mattress and bedroom floor samples during both seasons and in upholstered furniture during winter. For the nine significant season‐by‐location comparisons, EU/mg and EU/m2 were approximately three to six times greater in homes using evaporative coolers. A plausible explanation for these findings is that evaporative coolers serve as a reservoir and distribution system for Gram‐negative bacteria or their cell wall components in homes. 相似文献
5.
Merrill Schleier 《The Journal of Architecture》2013,18(3):365-385
Los Angeles's Griffith Observatory (1935) is the centrepiece and terminus for Nicholas Ray's film Rebel Without a Cause where its philosophical truths are housed and disseminated.1 Situated atop the Hollywood Hills, the classically styled, domed edifice serves as the site of some of the film's most important scenes, including the planetarium lecture (foreshadowing its pendant, the pivotal ‘chickie-run’ sequence), the knife fight between Jim and Buzz, and the Christ-like martyrdom of Plato. This article considers the manner in which the Observatory is invested with the task of structuring time while simulating the traumas of war, natural catastrophe, thermonuclear conflict and familial dysfunction. Its exterior and interior spaces are further enlisted by the director, Nicholas Ray, and the screenwriters, Irving Shulman and Stewart Stern, to foreshadow events and underscore thematic intent. The Observatory serves three major functions in Rebel. Its planetarium show creates a parallel between celestial and terrestrial events, especially its ‘end of the world’ lecture, which parallel the rebellious teenagers and their chaotic familial relationships. It is the setting for Plato's isolation and finally, at the film's conclusion, the existential loneliness of all humans. Lastly, its architectural properties—temple-like appearance and domical structure—serve as a microcosm of the universe and ultimately as an image of stability, underscored formally by the grandiose spectacle and elongated horizontal expanse of CinemaScope. 相似文献
6.
Grimshaw Andrew Morgan Mark Merrill Duane Kishimoto Hiro Savva Andreas Snelling David Smith Chris Berry Dave 《Computer》2009,42(2):27-34
To expand the use of distributed computer infrastructures as well as facilitate grid interoperability, OGSA has developed standards and specifications that address a range of scenarios, including high-throughput computing, federated data management, and service mobility. 相似文献
7.
This work examines the properties of starch esters for their possible application as environmentally degradable thermoplastics. The rheological, thermal, and mechanical properties of a series of fatty-acid esters of high-amylose starch (as well as the effects of adding plasticizer on some selected properties) were evaluated. The ester group acts like an internal plasticizer, with an increase in the size of the fatty-acid chain, resulting in greater internal plasticization. This is reflected in the rheological and thermal measurements as well as in the mechanical properties. Overall, larger ester groups and the addition of external plasticizer make these starch-based materials more processable and more ductile. However, comparing their properties and cost to commodity thermoplastics leads us to believe that their commercial applications are likely to be limited, at least in the near future. © 1995 John Wiley & Sons, Inc. 相似文献
8.
tRNA isoacceptors for aspartic acid, asparagine, histidine, and tyrosine are modified in the anticodon wobble position with the deazaguanine analogue queuine. Queuine modification is defective in many tumors and transformed cell lines, and the extent of hypomodification correlates with staging and outcome in numerous human tumors. The molecular role of queuine modification in normal cells and the mechanisms of queuine hypomodification in tumors are unknown. We have characterized nontransformed C3H10T1/2 murine fibroblasts (C3H) and their ras-transfected counterparts (RasC4) with respect to the causes and effects of queuine hypomodification. RasC4 cells are hypomodified for queuine compared with C3H cells, despite increase tRNA-guanine ribosyltansferase activity. Excess exogenous queuine can cause repletion of tRNA queuine levels in RasC4 cells. Queuine modification of both C3H and RasC4 cells can be decreased by treatment with 7-methylguanine. This treatment does not affect growth in monolayer culture but enhances anchorage-independent growth of RasC4 cells greatly. These cell lines may be useful systems for the study of queuine function in normal cells and the causes and consequences of hypomodification for queuine in tumors. 相似文献
9.
10.
Hiscock Merrill; Kinsbourne Marcel; Caplan Bruce; Swanson James M. 《Canadian Metallurgical Quarterly》1979,88(1):27
Administered dichotic digit tasks requiring free report and selective listening, respectively, to 20 6–16 yr old hyperactive children. Ss received methylphenidate before 2 experimental sessions and a placebo before 2 control sessions. The stimulant did not improve free-report performance significantly; rather it facilitated or impaired performance, depending on how it affected the order in which stimuli were reported. Similarly, medication had no effect on overall selective-listening performance, but it increased the difficulty of switching attention from one ear to the other. Results demonstrate that stimulants may act to maintain selective attention and to inhibit channel switching. Listening asymmetry, that is, right-ear superiority, was influenced by task variables but not by stimulant medication. (25 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献