全文获取类型
收费全文 | 612篇 |
免费 | 29篇 |
专业分类
电工技术 | 6篇 |
化学工业 | 168篇 |
金属工艺 | 14篇 |
机械仪表 | 8篇 |
建筑科学 | 35篇 |
矿业工程 | 2篇 |
能源动力 | 9篇 |
轻工业 | 80篇 |
水利工程 | 4篇 |
无线电 | 33篇 |
一般工业技术 | 88篇 |
冶金工业 | 93篇 |
原子能技术 | 2篇 |
自动化技术 | 99篇 |
出版年
2024年 | 1篇 |
2023年 | 12篇 |
2022年 | 24篇 |
2021年 | 34篇 |
2020年 | 19篇 |
2019年 | 8篇 |
2018年 | 12篇 |
2017年 | 14篇 |
2016年 | 27篇 |
2015年 | 21篇 |
2014年 | 20篇 |
2013年 | 38篇 |
2012年 | 34篇 |
2011年 | 38篇 |
2010年 | 31篇 |
2009年 | 31篇 |
2008年 | 40篇 |
2007年 | 42篇 |
2006年 | 29篇 |
2005年 | 20篇 |
2004年 | 19篇 |
2003年 | 16篇 |
2002年 | 13篇 |
2001年 | 4篇 |
2000年 | 10篇 |
1999年 | 4篇 |
1998年 | 12篇 |
1997年 | 8篇 |
1996年 | 7篇 |
1995年 | 5篇 |
1994年 | 6篇 |
1993年 | 2篇 |
1992年 | 7篇 |
1991年 | 5篇 |
1990年 | 5篇 |
1989年 | 1篇 |
1988年 | 2篇 |
1987年 | 2篇 |
1986年 | 4篇 |
1985年 | 4篇 |
1984年 | 1篇 |
1983年 | 3篇 |
1981年 | 2篇 |
1978年 | 1篇 |
1977年 | 2篇 |
1974年 | 1篇 |
排序方式: 共有641条查询结果,搜索用时 15 毫秒
631.
Vicky Jasson Imca Sampers Nadine Botteldoorn Francisco Lpez-Glvez Leen Baert Sarah Denayer Andreja Rajkovic Ihab Habib Lieven De Zutter Johan Debevere Mieke Uyttendaele 《International journal of food microbiology》2009,135(3):248-253
A comparative study examining Bolton broth and Preston broth for enrichment and reliable detection of Campylobacter jejuni (both healthy and freeze stressed cells) was performed. Tested as pure cultures, Bolton broth enabled faster resuscitation and growth of C. jejuni compared to Preston broth. When C. jejuni was co-incubated with extended-spectrum-beta-lactamase (ESBL) producing Escherichia coli isolated from Belgian poultry meat preparations, the latter dominated in the Bolton enrichment broth and crowded the mCCDA plates. This resulted in the inability to recover C. jejuni by ISO 10272-1:2006 standard method. Preston broth did not support the growth of the ESBL E. coli isolates, but showed longer detection time of C. jejuni compared to Bolton broth. The use of the same antibiotic (sodium cefoperazone) in Bolton broth and in mCCDA plates may explain the problems encountered for detection of C. jejuni, as high numbers of ESBL E. coli present after enrichment in Bolton broth, also caused overgrowth and masked the few C. jejuni colonies present on the mCCDA plates. The use of Campylobacter spp. specific real-time PCR circumvented these problems and enabled rapid detection of the pathogen after 24 h enrichment in both Bolton and Preston broth, for both healthy and freeze stressed cells. 相似文献
632.
633.
Davis Shane P.; Arnette Natalie C.; Bethea Kafi S.; Graves Kelly N.; Rhodes Miesha N.; Harp Sharon E.; Dunn Sarah E.; Patel Meghna N.; Kaslow Nadine J. 《Canadian Metallurgical Quarterly》2009,40(2):141
Background information is provided on the link between intimate partner violence and suicidal behavior, as this association sets the stage for interventions for this population. Attention then is paid to the theoretical components of an innovative culturally competent intervention for abused and suicidal, low-income African American women, entitled Grady Nia Project. The intervention is guided by the theory of triadic influence. Cultural competence components essential to implementing an intervention with this unique population and guided by this model are articulated. The Grady Nia Project is then described in detail, focusing on the context in which the intervention is conducted, the content of the 10 sessions, and treatment satisfaction and outcome data. Implications for culturally informed practice with abused, suicidal African American women are noted. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
634.
Felix Feistel Christian Paetz Riya C. Menezes Daniel Veit Bernd Schneider 《Journal of chemical ecology》2018,44(5):497-509
Salicortin is a phenolic glucoside produced in Salicaceae as a chemical defense against herbivory. The specialist lepidopteran herbivorous larvae of Cerura vinula are able to overcome this defense. We examined the main frass constituents of C. vinula fed on Populus nigra leaves, and identified 11 quinic acid derivatives with benzoate and/or salicylate substitution. We asked whether the compounds are a result of salicortin breakdown and sought answers by carrying out feeding experiments with highly 13C-enriched salicortin. Using HRMS and NMR analyses, we were able to confirm that salicortin metabolism in C. vinula proceeds through deglucosylation and ester hydrolysis, after which saligenin is oxidatively transformed into salicylic acid and, eventually, conjugated to quinic acid. To the best of our knowledge, this is the first report of a detoxification pathway based on conjugation with quinic acid. 相似文献
635.
636.
Die Traunbrücke Steyrermühl ist Teil der A1 Westautobahn und wurde in den Jahren 1959 und 1960 errichtet. Die 18‐feldrige Stahlbetonbrücke besteht aus zwei Richtungstragwerken und weist eine Gesamtlänge von 240,45 m auf. Im Hinblick auf die Gewährleistung der Tragsicherheit und Funktionsfähigkeit der Brücke wurden während der Sprengung des Richtungstragwerks Salzburg im August 2010 das unmittelbar benachbarte, zunächst bestehen bleibende Richtungstragwerk Wien überwacht und die Auswirkungen der Sprengung bewertet, wobei besonderes Augenmerk auf die primäre Tragstruktur (Bogen) gelegt wurde. Da am Tragwerk bereits im Jahr 2005 eine dynamische Referenzmessung mit BRIMOS® durchgeführt wurde, konnte die aktuelle Untersuchung (Messung 2010) dadurch entsprechend effizienter gestaltet werden. Mit Hilfe ausgewählter Einzelpunkte am Brückentragwerk (HOT SPOTS) konnten das maßgebliche Tragverhalten der Brücke und etwaige Veränderungen umfassend beschrieben und quantifiziert werden. Ein direkter Vergleich im Abstand von fünf Jahren zeigt den Verlauf der gemessenen Tragfähigkeit über die Zeit (Brückendeck unter dem Einfluss der Verkehrsbelastung bzw. der Sprengung). Blast of the Westbound Bridge Structure and Evaluation of its Affection on the remaining Eastbound Bridge Structure with BRIMOS® Structural Health Monitoring. The bridge object is part of the A1 highway and was constructed in 1959. It is composed of 18‐spans (reinforced concrete) and has a total length of 240,45 m. While the bridge structure — related with the driving direction Salzburg — was removed (blown) in August 2010, the remaining structure (driving direction Vienna) was monitored in order to evaluate the impact of the blasting with regard to its structural safety and operability. The investigation was focused on the primary load‐bearing structure (arch). Due to the fact that an initial dynamic measurement with BRIMOS® has been conducted already in 2005, the prevailing investigation (measurement 2010) could be configured more efficiently. Measurements at selected single bridge locations (HOT SPOTS) enabled a comprehensive documentation and quantification of the bridge’s decisive structural behaviour and possible changes respectively. A direct comparison after 5 years of structural service life shows the progression of the measured structural resistance over time (bridge deck under the influence of traffic load and the bridge blasting). 相似文献
637.
638.
Trinh Anh Truc Vu Ke Oanh Colette Lacabanne Nadine Pébère 《Surface & coatings technology》2008,202(20):4945-4951
In the present work, indole-3 butyric acid (IBA) was inserted between montmorillonite clay platelets by cation exchange. The clay treated with the organic compound (IBA-modified clay) was then dispersed in an epoxy resin at a low concentration (2 wt.%). IBA was chosen to act both as an inhibitor and an adherence promoter. The effect of the IBA-modified clay on the microstructure and on the protective properties of the epoxy coating deposited on carbon steel was evaluated by a thermostimulated-current (TSC) method and by electrochemical impedance spectroscopy (EIS). The TSC measurements showed the specific action of IBA-modified clay which decreased the molecular mobility of the polymer chain by comparison with the pure epoxy. Impedance measurements corroborated the role of the modified clay on the barrier properties of the coating which remained high as a function of exposure time in a 0.5 M NaCl solution. The corrosion resistance of the carbon steel coated with the epoxy resin containing IBA-modified clay was significantly higher than that obtained with the clear coat. Polarization curves plotted in the presence of an artificial defect demonstrated the inhibitive role of IBA at the carbon steel/coating interface. The good adherence of the coating was seen during salt spray test. 相似文献
639.
This article surveys mathematical models and methods used for the physical layout of printed circuit boards, in particular component placement and wire routing. The main concepts are briefly described together with relevant references. Work supported by the DFG Research Center Matheon in Berlin. 相似文献
640.