全文获取类型
收费全文 | 3244篇 |
免费 | 192篇 |
国内免费 | 1篇 |
学科分类
工业技术 | 3437篇 |
出版年
2023年 | 40篇 |
2022年 | 35篇 |
2021年 | 172篇 |
2020年 | 84篇 |
2019年 | 82篇 |
2018年 | 101篇 |
2017年 | 78篇 |
2016年 | 112篇 |
2015年 | 101篇 |
2014年 | 100篇 |
2013年 | 189篇 |
2012年 | 165篇 |
2011年 | 205篇 |
2010年 | 136篇 |
2009年 | 124篇 |
2008年 | 132篇 |
2007年 | 129篇 |
2006年 | 105篇 |
2005年 | 98篇 |
2004年 | 89篇 |
2003年 | 71篇 |
2002年 | 76篇 |
2001年 | 49篇 |
2000年 | 45篇 |
1999年 | 40篇 |
1998年 | 110篇 |
1997年 | 83篇 |
1996年 | 58篇 |
1995年 | 56篇 |
1994年 | 55篇 |
1993年 | 69篇 |
1992年 | 30篇 |
1991年 | 16篇 |
1990年 | 31篇 |
1989年 | 27篇 |
1988年 | 24篇 |
1987年 | 22篇 |
1986年 | 19篇 |
1985年 | 18篇 |
1984年 | 17篇 |
1983年 | 15篇 |
1982年 | 16篇 |
1981年 | 16篇 |
1980年 | 11篇 |
1979年 | 17篇 |
1977年 | 14篇 |
1976年 | 33篇 |
1975年 | 18篇 |
1974年 | 11篇 |
1972年 | 9篇 |
排序方式: 共有3437条查询结果,搜索用时 234 毫秒
1.
2.
3.
4.
Biocatalysis offers a broad spectrum of possible ecological and economic advantages over conventional chemical catalysis processes, e.g., lower energy consumption and high enantio selectivity. The focus of this work is on gas-liquid reactions. These are of great importance in the chemical and biochemical industry and subject of current research since they are often limited by mass transfer or show low selectivity. Different suitable biocatalytically gas-liquid reaction systems were tested in capillary reactor designs in order to obtain information about the interaction between reaction and fluid mechanics. Furthermore, an optical measuring method was established. The experiments were performed in batch mode in a glass beaker with a flow cuvette for UV/Vis measurement of product concentration. 相似文献
5.
6.
7.
Norris Fran H.; Murphy Arthur D.; Baker Charlene K.; Perilla Julia L.; Rodriguez Francisco Gutiérrez; Rodriguez José de Jesús Gutiérrez 《Canadian Metallurgical Quarterly》2003,112(4):646
Prevalence rates of trauma and posttraumatic stress disorder (PTSD) were estimated from a probability sample of 2,509 adults from 4 cities in Mexico. PTSD was assessed according to Diagnostic and Statistical Manual of Mental Disorders (American Psychiatric Association, 1994) criteria using the Composite International Diagnostic Interview (CIDI; WHO, 1997). Lifetime prevalence of exposure and PTSD were 76% and 11.2%, respectively. Risk for PTSD was highest in Oaxaca (the poorest city), persons of lower socioeconomic status, and women. Conditional risk for PTSD was highest following sexual violence, but nonsexual violence and traumatic bereavement had greater overall impact because of their frequency. Of lifetime cases, 62% became chronic; only 42% received medical or professional care. The research demonstrates the importance of expanding the epidemiologic research base on trauma to include developing countries around the world. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
8.
Examined the theory that chronic migraine headaches can lead to permanent changes in brain function in 71 female college students. Ss were 20 classic migraineurs, 27 common migraineurs, and 24 controls. No significant group differences were found on the Halstead Reitan Neuropsychological Test Battery and additional memory tests. Classic migraineurs had significantly higher scores than common migraineurs on the Hysteria and Paranoia scales of the Minnesota Multiphasic Personality Inventory (MMPI) and significantly higher scores than the controls on Hypochondriasis and Hysteria scales. Explanations for the lack of cognitive deficits in this group are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
9.
While Beck asserts that agility is only possible through greater discipline on the part of everyone involved, Boehm counters that you don't broaden the definition of "discipline" by rejecting parts of it. Yet, from inside extreme programming, it seems that the only way to achieve the desired results is to view the world in 'both-and" terms instead of "either-or" terms. 相似文献
10.
Emergency department status boards: user-evolved artefacts for inter- and intra-group coordination 总被引:1,自引:1,他引:0
Robert L. Wears Shawna J. Perry Stephanie Wilson Julia Galliers James Fone 《Cognition, Technology & Work》2007,9(3):163-170
Large, easily viewed status boards are commonly used in some healthcare settings such as emergency departments, operating
theaters, intensive care units, and inpatient wards. Because these artefacts were developed by front-line users, and have
little to no supervisory or regulatory control, they offer valuable insights into the theories of work and hazard held by
those users. Although the status boards case were locally developed over many years for within-group coordination, they have
also become useful for between-group coordination across organizational boundaries. In this paper, we compare and contrast
the use of such status boards in two disparate settings: a US emergency department, and a UK pediatric ward, and note striking
similarities in their form and usage, despite the large differences in setting. 相似文献