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91.
A dual flow continuous culture system was used to determine the effects of four protein sources (soybean meal, Ca-ligno-sulfonate treated-soybean meal, blood meal, and feather meal), supplied individually or in combination in diets composed predominantly of alkaline hydrogen peroxide-treated wheat straw, on ruminal microbial fermentation and amino acid flow. Diets containing blood meal had lower organic matter and fiber digestion, NH3 N and VFA concentrations, and CP degradation but higher non-NH3 N, dietary N, total amino acid, and essential amino acid flows. Feather meal fed alone or combined with other sources was not different from the blood meal diet in organic matter and fiber digestion. Combining treated soybean meal and blood meal resulted in similar organic matter and fiber digestibilities compared with the soybean meal diets. This combination was similar to the treated soybean meal diet in VFA concentration, non-NH3 N, and essential and total amino acid flows; however, amino acid profile was different with this combination, showing higher histidine and leucine flows. Results from this study suggest that amino acid profiles of digesta leaving the rumen may be manipulated by choice of protein supplement when diets containing a low protein, highly fermentable feedstuff such as alkaline hydrogen, peroxide-treated wheat straw are fed. 相似文献
92.
正Wieden+Kennedy是可口可乐(Coca Cola)、耐克(Nike)、以及星巴克(Starbucks)等国际知名品牌的广告代理商,它的办公楼的设计理念融合了阿姆斯特丹运河上的两座国家纪念碑的概念。这个项目的复杂性在于需要将不同年代的旧建筑改造成一个21世纪的创意工作环境。因此通过设计既要体现建筑群本身的纪念价值,还要建造一座定义明确、空间宽阔的办公楼。这座办公楼需要集日常办公、会议、商讨、休 相似文献
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Luca Aceto Wan Fokkink Anna Inglfsdttir Bas Luttik 《Theoretical computer science》2005,330(3):377-405
This paper confirms a conjecture of Bergstra and Klop's from 1984 by establishing that the process algebra obtained by adding an auxiliary operator proposed by Hennessy in 1981 to the recursion free fragment of Milner's Calculus of Communicating Systems is not finitely based modulo bisimulation equivalence. Thus, Hennessy's merge cannot replace the left merge and communication merge operators proposed by Bergstra and Klop, at least if a finite axiomatization of parallel composition modulo bisimulation equivalence is desired. 相似文献
95.
LJ Hofland WW De Herder HA Visser-Wisselaar C Van Uffelen M Waaijers J Zuyderwijk P Uitterlinden MJ Kros PM Van Koetsveld SW Lamberts 《Canadian Metallurgical Quarterly》1997,82(9):3011-3018
The effects of somatostatin (SS-14 and/or SS-28) and of the three octapeptide SS-analogs that are available for clinical use (octreotide, BIM-23014 and RC-160) on hormone release by primary cultures of 15 clinically nonfunctioning pituitary adenomas (NFA), 7 prolactinomas, and 2 insulinomas were investigated. In the pituitary adenoma cultures, a comparison was made with the effects of the dopamine (DA) agonists bromocriptine and/or quinagolide. In 5 NFAs, 2 prolactinomas and 1 insulinoma somatostatin receptor (subtype) expression was determined by ligand binding studies and by in situ hybridization to detect sst1, sst2, and sst3 messenger RNAs (mRNAs). Four NFA cultures did not secrete detectable amounts of alpha-subunit, FSH, and/or LH. In the other cultures, hormone and/or subunit release was inhibited by DA-agonists (10 nM) in 9 of 11, by SS (10 nM) in 7 of 11, and by octapeptide SS-analogs (10 nM) in 3 of 10 cultures. In three NFA cultures, hormone release was sensitive to SS but not to SS-analogs. In all cultures, except for one, DA-agonists were the most effective in inhibiting hormone release. In the prolactinoma cultures, PRL release was inhibited by DA-agonists (10 nM) in 7 of 7, by SS in 4 of 4, and by octapeptide SS-analogs in 3 of 7 cultures. A dissociation between the effects of SS and SS-analogs was found in 3 cases. In the cultures sensitive to both bromocriptine and SS-28, bromocriptine was the most potent compound in 2 out of 4 cultures. In the 2 other cultures, both compounds were equally effective. In 2 insulinoma cultures, insulin release was inhibited by SS, and by octapeptide SS-analogs in only one. The presence or absence of an inhibitory effect by octreotide was in all cases in parallel with the presence or absence of the inhibitory effect by BIM-23014 and RC-160. Autoradiographic studies using [125I-Tyr0]SS28 showed specific binding in 4 of 5 NFAs, 1 of 2 prolactinomas, and 1 of 1 insulinoma. Specific [125I-Tyr3]octreotide binding was found in 2 of 5 NFAs, in 1 of 2 prolactinomas, and in the insulinoma. Two NFAs showed binding of SS28, but not of the sst2.5 specific ligand octreotide. The tumors showed variable sst1 and/or sst3 mRNA expression, whereas no sst2 expression was found. In conclusion, a dissociation between the inhibitory effects of SS on the one hand and of the octapeptide SS-analogs octreotide, BIM-23014 and RC-160 on the other hand, is observed in a small subgroup of NFAs, prolactinomas, and insulinomas, suggesting that novel sst subtype specific SS-analogs might be of benefit in the treatment of selected patients with somatostatin receptor positive secreting tumors not responding to octapeptide SS-analogs. However, in the majority of NFAs and prolactinomas, DA-agonists were equally or more effective than SS in the suppression of tumoral secretion products. 相似文献
96.
Hulsken B Van Hameren R Gerritsen JW Khoury T Thordarson P Crossley MJ Rowan AE Nolte RJ Elemans JA Speller S 《Nature nanotechnology》2007,2(5):285-289
Many chemical reactions are catalysed by metal complexes, and insight into their mechanisms is essential for the design of future catalysts. A variety of conventional spectroscopic techniques are available for the study of reaction mechanisms at the ensemble level, and, only recently, fluorescence microscopy techniques have been applied to monitor single chemical reactions carried out on crystal faces and by enzymes. With scanning tunnelling microscopy (STM) it has become possible to obtain, during chemical reactions, spatial information at the atomic level. The majority of these STM studies have been carried out under ultrahigh vacuum, far removed from conditions encountered in laboratory processes. Here we report the single-molecule imaging of oxidation catalysis by monitoring, with STM, individual manganese porphyrin catalysts, in real time, at a liquid-solid interface. It is found that the oxygen atoms from an O2 molecule are bound to adjacent porphyrin catalysts on the surface before their incorporation into an alkene substrate. 相似文献
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Fabíola Cristina de Oliveira Eduardo Basílio de Oliveira Abraham Damian Giraldo Zuñiga Edwin E. Garcia Rojas 《Critical reviews in food science and nutrition》2016,56(7):1108-1125
The products formed by glycosylation of food proteins with carbohydrates via the Maillard reaction, also known as conjugates, are agents capable of changing and improving techno-functional characteristics of proteins. The Maillard reaction uses the covalent bond between a group of a reducing carbohydrates and an amino group of a protein. This reaction does not require additional chemicals as it occurs naturally under controlled conditions of temperature, time, pH, and moisture. Moreover, there is growing interest in modifying proteins for industrial food applications. This review analyses the current state of art of the Maillard reaction on food protein functionalities. It also discusses the influence of the Maillard reaction on the conditions and formulation of reagents that improve desirable techno-functional characteristics of food protein. 相似文献
100.
Renger H. Jellema Shaji Krishnan Margriet M.W.B. Hendriks Bas Muilwijk 《Chemometrics and Intelligent Laboratory Systems》2010,104(1):132-139
Extraction of peak areas and mass spectral information from chromatography mass spectral data such as obtained in metabolomics measurements requires much effort and the quality is often subjective to the operator that handles the data at hand. In multiple file deconvolution, all samples are processed simultaneously and alignment issues are part of the modeling strategy. However, processing the total data set as a whole is an impossible task and therefore the data processing task requires segmentation. Two intertwined divide and conquer strategies are proposed. The first strategy divides the retention time axis into equal parts and the second strategy divides the total data set into a model and a prediction data set. Dividing the data into smaller segments allows us to conquer the total problem. Post processing of the resulting matrices with peak areas and mass spectra ensures that a matrix with peak areas ready for statistics and a matrix with mass spectral information ready for peak annotation is obtained. The proposed methodology is implemented within a package called TNO-DECO but can easily be implemented in other data pre-processing approaches. 相似文献