首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   344篇
  免费   9篇
  国内免费   1篇
电工技术   1篇
化学工业   70篇
金属工艺   9篇
机械仪表   11篇
建筑科学   5篇
能源动力   18篇
轻工业   36篇
石油天然气   4篇
无线电   53篇
一般工业技术   63篇
冶金工业   36篇
原子能技术   13篇
自动化技术   35篇
  2022年   5篇
  2021年   4篇
  2020年   8篇
  2019年   5篇
  2018年   9篇
  2017年   7篇
  2016年   7篇
  2015年   6篇
  2014年   8篇
  2013年   20篇
  2012年   12篇
  2011年   17篇
  2010年   13篇
  2009年   14篇
  2008年   19篇
  2007年   10篇
  2006年   8篇
  2005年   20篇
  2004年   11篇
  2003年   14篇
  2002年   5篇
  2001年   5篇
  2000年   4篇
  1999年   8篇
  1998年   19篇
  1997年   12篇
  1996年   7篇
  1995年   3篇
  1994年   5篇
  1993年   7篇
  1992年   6篇
  1990年   3篇
  1989年   3篇
  1988年   3篇
  1987年   2篇
  1986年   4篇
  1985年   4篇
  1984年   4篇
  1982年   2篇
  1981年   5篇
  1980年   4篇
  1979年   3篇
  1978年   3篇
  1975年   2篇
  1973年   2篇
  1969年   1篇
  1968年   3篇
  1966年   1篇
  1957年   1篇
  1956年   2篇
排序方式: 共有354条查询结果,搜索用时 15 毫秒
61.

1 Scope

Shellfish allergy is an increasing global health priority, frequently affecting adults. Molluscs are an important shellfish group causing food allergy but knowledge of their allergens and cross‐reactivity is limited. Optimal diagnosis of mollusc allergy enabling accurate advice on food avoidance is difficult. Allergens of four frequently ingested Asia‐Pacific molluscs are characterized: Sydney rock oyster (Saccostrea glomerata), blue mussel (Mytilus edulis), saucer scallop (Amusium balloti), and southern calamari (Sepioteuthis australis), examining cross‐reactivity between species and with blue swimmer crab tropomyosin, Por p 1.

2 Methods and results

IgE ELISA showed that cooking increased IgE reactivity of mollusc extracts and basophil activation confirmed biologically relevant IgE reactivity. Immunoblotting demonstrated strong IgE reactivity of several proteins including one corresponding to heat‐stable tropomyosin in all species (37–40 kDa). IgE‐reactive Sydney rock oyster proteins were identified by mass spectrometry, and the novel major oyster tropomyosin allergen was cloned, sequenced, and designated Sac g 1 by the IUIS. Oyster extracts showed highest IgE cross‐reactivity with other molluscs, while mussel cross‐reactivity was weakest. Inhibition immunoblotting demonstrated high cross‐reactivity between tropomyosins of mollusc and crustacean species.

3 Conclusion

These findings inform novel approaches for reliable diagnosis and improved management of mollusc allergy.  相似文献   
62.
One of the most desirable hair attributes to consumers, irrespective of ethnic background, is hair shine. The light reflected from a fiber has two components, specular and diffuse. The specular fraction of reflected light from the front surface of the fiber is generally recognized as a contributor to high luster. The distinction between specular and diffuse reflection is, however, not always clearly defined. In this study an attempt has been made to differentiate between specular and diffuse reflectance by analyzing mathematically goniophotometric curves of light reflected from unaltered single hair fibers from European, African, and Asian ethnic groups. The effect of macroscopic characteristics of the hair fibers, such as fiber diameter, cross-sectional shape, and curvature on luster is demonstrated. Results indicate that broadening of the specular peak reduces luster values, and is related to these characteristics. Thus, specular peak broadening is one of the important features to take into account when evaluating luster. Therefore, a new method for luster evaluation from goniophotometric curves is proposed. Additionally, we present the general model for light scattering, showing how scattering by surface roughness of different origin and magnitudes, and the scattering and absorption processes by the hair's interior, affect the position of the specular reflectance peak and its broadening.  相似文献   
63.
Chandra  Anant  Ghosh  Satyajit 《AI & Society》2020,35(2):401-407
AI & SOCIETY - India’s energy demand is predicted to rise by 135% within a span of 20 years. Coping up with surging energy demands requires several reforms in both renewable and...  相似文献   
64.
This study investigates the relation between the maturity of IT governance processes and the IT governance disclosure of firms. Furthermore, it examines whether the strategic role of IT in an industry induces systematic variation in IT governance disclosure. Based on a content analysis of annual reports and a field survey on the maturity of the implementation of COBIT processes, the results demonstrate a role of IT governance frameworks in stimulating accountability and transparency via enhanced external reporting of relevant IT information to external stakeholders, in particular in settings where the strategic role of IT is high.  相似文献   
65.
Upwind schemes have been evaluated for their accuracy based upon steady-state solutions of Euler and Navier–Stokes equations. It includes the flux-vector splitting schemes due to Steger–Warming and Van Leer, flux-difference splitting schemes due to Roe and Osher, and the hybrid schemes, AUSM (Advection Upstream Splitting method) and HUS (Hybrid Upwind Splitting). Computations for inviscid and viscous compressible flows that are well documented in literature have been carried out in a unified framework. Comparisons of lift, drag, skin-friction and heat-transfer coefficients have been established with reference computational and experimental results.  相似文献   
66.
67.
Experimental restrictions imposed on the collection and detection of shortwave-infrared photons (SWIR) have impeded single molecule work on a large class of materials whose optical activity lies in the SWIR. Here we report the successful observation of room-temperature single nanocrystal photoluminescence at SWIR wavelengths using a highly efficient multielement superconducting nanowire single photon detector. We confirm that the photoluminescence from single lead sulfide nanocrystals is strongly antibunched, demonstrating the feasibility of performing sophisticated photon correlation experiments on individual weak SWIR emitters, and, more broadly, paving the way for sensitive measurements of spectral observables on infrared quantum systems that are incompatible with current detection techniques.  相似文献   
68.
Use of Passive Gamma Scanning for non destructive evaluation of PuO2 content in mixed oxide (MOX) fuels for fast reactors is demonstrated. Experiments have been carried out on MOX fuel pins for the hybrid core of Fast Breeder Test Reactor having nominal PuO2 content of 44% and MOX pins having nominal PuO2 content of 21% for the Prototype Fast Breeder Reactor. A comparison of results obtained using a conventional NaI(Tl) detector and that using a through well shaped detector is also presented.  相似文献   
69.
TNT is one of the most commonly used nitro aromatic explosives for landmines of military and terrorist activities. As a result, there is an urgent need for rapid and reliable methods for the detection of trace amount of TNT for screenings in airport, analysis of forensic samples, and environmental analysis. Driven by the need to detect trace amounts of TNT from environmental samples, this article demonstrates a label-free, highly selective, and ultrasensitive para-aminothiophenol (p-ATP) modified gold nanoparticle based dynamic light scattering (DLS) probe for TNT recognition in 100 pico molar (pM) level from ethanol:acetonitile mixture solution. Because of the formation of strong π-donor-acceptor interaction between TNT and p-ATP, para-aminothiophenol attached gold nanoparticles undergo aggregation in the presence of TNT, which changes the DLS intensity tremendously. A detailed mechanism for significant DLS intensity change has been discussed. Our experimental results show that TNT can be detected quickly and accurately without any dye tagging in 100 pM level with excellent discrimination against other nitro compounds.  相似文献   
70.
Impregnated Agglomerate Pelletization (IAP) technique has been developed at Advanced Fuel Fabrication Facility (AFFF), BARC, Tarapur, for manufacturing (Th,233U)O2 mixed oxide fuel pellets, which are remotely fabricated in hot cell or shielded glove box facilities to reduce man-rem problem associated with 232U daughter radionuclides. This technique is being investigated to fabricate the fuel for Indian Advanced Heavy Water Reactor (AHWR). In the IAP process, ThO2 is converted to free flowing spheroids by powder extrusion route in an unshielded facility which are then coated with uranyl nitrate solution in a shielded facility. The dried coated agglomerate is finally compacted and then sintered in oxidizing/reducing atmosphere to obtain high density (Th,U)O2 pellets. In this study, fabrication of (Th,U)O2 mixed oxide pellets containing 3–5 wt.% UO2 was carried out by IAP process. The pellets obtained were characterized using optical microscopy, XRD and alpha autoradiography. The results obtained were compared with the results for the pellets fabricated by other routes such as Coated Agglomerate Pelletization (CAP) and Powder Oxide Pelletization (POP) route.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号