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31.
Competition of urea with oilseed proteins in ruminant feeding depends primarily on economic relationships between these ingredients,
cost of energy sources and proper feed formulation. A general summary of the more important factors to consider in replacing
protein with nonprotein nitrogen in ruminant feeds is presented. Estimated urea utilization in the U.S. grew at a 15.5% compound
annual rate from 1962 to 1966. From 1966–1969, usage increased at a 5% compound annual rate. Approximately 650,000 tons of
urea were used by the U.S. Feed industry in 1969. Urea usage is expected to continue to grow in the United States. The high
cost of energy sources in Western Europe will tend to slow its use by the feed industry of that area. In general, competition
of urea with oilseed proteins will be greatest with heavy grain feeding of cattle, low cost grains and high priced oilseed
meals.
One of 16 papers being published from the Symposium, “Oilseed Processors Challenged by World Protein Needs,” presented at
the ISF-AOCS World Congress, Chicago, September 1970. 相似文献
32.
33.
针对舰船用海水冷却设备的腐蚀情况的调查,提出了 基本的舰用冷却设备的腐蚀控制原则,并论述了电绝缘措施控制电偶腐蚀、非金属复合层保 护、牺牲阳极和外加电流阴极保护等几种防腐方法,实践证明通过对冷却设备采用本文中提 出的防腐措施,可以很好的解决舰船冷却设备的腐蚀防护问题. 相似文献
34.
Valentin I. E. Queloz Marine E. F. Bouduban Ines García‐Benito Alexander Fedorovskiy Simonetta Orlandi Marco Cavazzini Gianluca Pozzi Harsh Trivedi Doru C. Lupascu David Beljonne Jaques‐E Moser Mohammad Khaja Nazeeruddin Claudio Quarti Giulia Grancini 《Advanced functional materials》2020,30(28)
2D hybrid perovskites (2DP) are versatile materials, whose electronic and optical properties can be tuned through the nature of the organic cations (even when those are seemingly electronically inert). Here, it is demonstrated that fluorination of the organic ligands yields glassy 2DP materials featuring long‐lived correlated electron–hole pairs. Such states have a marked charge‐transfer character, as revealed by the persistent Stark effect in the form of a second derivative in electroabsorption. Modeling shows that electrostatic effects associated with fluorination, combined with the steric hindrance due to the bulky side groups, drive the formation of spatially dislocated charge pairs with reduced recombination rates. This work enriches and broadens the current knowledge of the photophysics of 2DP, which will hopefully guide synthesis efforts toward novel materials with improved functionalities. 相似文献
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36.
Marine A. C. Moussu Luisa Ciobanu Sergej Kurdjumov Elizaveta Nenasheva Boucif Djemai Marc Dubois Andrew G. Webb Stefan Enoch Pavel Belov Redha Abdeddaim Stanislav Glybovski 《Advanced materials (Deerfield Beach, Fla.)》2019,31(30)
The spatial resolution and signal‐to‐noise ratio (SNR) attainable in magnetic resonance microscopy (MRM) are limited by intrinsic probe losses and probe–sample interactions. In this work, the possibility to exceed the SNR of a standard solenoid coil by more than a factor‐of‐two is demonstrated theoretically and experimentally. This improvement is achieved by exciting the first transverse electric mode of a low‐loss ceramic resonator instead of using the quasi‐static field of the metal‐wire solenoid coil. Based on theoretical considerations, a new probe for microscopy at 17 T is developed as a dielectric ring resonator made of ferroelectric/dielectric low‐loss composite ceramics precisely tunable via temperature control. Besides the twofold increase in SNR, compared with the solenoid probe, the proposed ceramic probe does not cause static‐field inhomogeneity and related image distortion. 相似文献
37.
Dr. Marine Blanchet Dr. Diane Borselli Dr. Anne Rodallec Dr. Franck Peiretti Nicolas Vidal Dr. Jean‐Michel Bolla Dr. Carole Digiorgio Kelly R. Morrison Prof. William M. Wuest Dr. Jean Michel Brunel 《ChemMedChem》2018,13(10):1018-1027
The emergence of multidrug‐resistant bacteria and pathogens has created an urgent need for the development of new antibiotics. Herein we report our investigations into the broad‐spectrum activity of an easily prepared water‐soluble polyaminosterol compound, namely claramine A1, against both drug‐sensitive and drug‐resistant Gram‐negative and Gram‐positive bacterial strains. We also report its peculiar mechanism of action, which differs from that of all the other well‐known classes of antibiotics, toward Gram‐negative and Gram‐positive bacteria. Given their low cytotoxicity, this class of compounds based on claramine A1 could constitute an effective response to combat the emergence of multidrug‐resistant bacteria and nosocomial diseases. 相似文献
38.
On the origin of the blue/green color of blast‐furnace slag‐based materials: Sulfur K‐edge XANES investigation 下载免费PDF全文
Mohend Chaouche Xiao Xiao Gao Martin Cyr Marine Cotte Laurent Frouin 《Journal of the American Ceramic Society》2017,100(4):1707-1716
Slag‐based materials including mortars, concretes, Ca‐geopolymers, etc., are known to display a fascinating blue/green color upon hydration. This specific color is of particular concern in applications where visual esthetics are important. Yet only limited studies have been devoted to this phenomenon so far and its origin remains unexplained. It has sometimes been attributed, without any experimental evidence, to the presence of polysulfur species in the slag. To address the origin of this coloration, sulfur K‐edge X‐ray absorption near edge structure (XANES) spectroscopy was used to investigate the evolution of the speciation of sulfur during slag hydration. Three methods of slag activation were considered: thermal, portland cement, and sodium silicate. The impact of the activation method on the sulfur K‐edge XANES spectrum was examined first. Then, a comparison was made between the XANES of blue and white samples or zones with or without the blue color within the same sample. Independently of the activation route, the blue color was found to be unambiguously related to the presence of a prepeak in the corresponding XANES spectrum. This feature was absent for white samples or white zones. The prepeak, which was located at lower energy than the peak corresponding to the most common reduced sulfur species, was attributed to the presence of the trisulfur radical anion S3?. This blue chromophore is known to be at the origin of the deep blue color of the stone lapis lazuli or the ultramarine pigment (derived from lazurite). 相似文献
39.
ZnO@mesoporous silica nanocomposite was prepared by the impregnation method, and very efficient laser action was highlighted. As revealed by high-resolution transmission electron microscopy (HR-TEM), nanometric ZnO particles are confined inside the mesochannels of CMI-1 mesoporous silicas. Upon excitation at 3.6?eV of a femtosecond pulsed laser and at low pumping intensity, the ZnO@mesoporous silica showed a broad photoluminescence (PL) band corresponding to the excitonic recombination of ZnO. When the pumping intensity is increased up to a threshold (2.5?mJ?cm(-2)), the excitonic emission turns to stimulated emission through a mechanism which will be discussed. The same threshold value was obtained with another excitation source and nanocomposites with different ZnO loadings inside the CMI-1 mesoporous silica. These results allow a better understanding of the random laser effect in ZnO@mesoporous silica and, consequently, a model has been proposed to explain this phenomenon. Based on these new observations, many new applications can be considered since short-wavelength devices are required by industry to design new information storage supports. 相似文献
40.
Bussy C Cambedouzou J Lanone S Leccia E Heresanu V Pinault M Mayne-L'hermite M Brun N Mory C Cotte M Doucet J Boczkowski J Launois P 《Nano letters》2008,8(9):2659-2663
X-ray fluorescence microscopy (microXRF) is applied for the first time to study macrophages exposed to unpurified and purified single-walled (SW) and multiwalled (MW) carbon nanotubes (CNT). Investigating chemical elemental distributions allows one to (i) image nanotube localization within a cell and (ii) detect chemical modification of the cell after CNT internalization. An excess of calcium is detected for cells exposed to unpurified SWCNT and MWCNT and related toxicological assays are discussed. 相似文献