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101.
The Nitrile Carboxamide Rearrangement By reaction of cyclohexanone-2-carboxamide ( 4 ) with cyan amide 1-cyano-cyclohex-1-en-2-yl-urea ( 6 ) is formed via nitrile carboxamide rearrangement. Whilst compound 6 with 1,2-diaminobenzene hydrochloride forms 11-amino-1 H-2,3,4,5-tetrahydrodibenzo[b,e][1,4]diazepin hydrochloride ( 8 and 8a ), compound 6 and 1,2-diaminobenzene form hexahydro-benzimidazo[1,2-c]-quinazolin-6-one ( 12 ). Compound 8 with sodium hydroxide yields 11-amino-1 H-2,3,4,11a-tetrahydrodibenzo[b,e]-[1,4]diazepin ( 9 ). Compound 6 reacts with cyclohexylamine to form N-(1-cyanocyclohex-1-en-2-yl)-N′-cyclohexyl urea ( 10 ). Compound 10 with 1,4- or 1,2-diaminobenzene hydrochloride yields compound 7 and 8 . In alkaline solution 10 cyclises to 4-amino-3-cyclohexyl-2,3,5,6,7,8-hexahydroquinazolin-2-one ( 11 ). Compound 4 and malonitrile form either 3-amino-4-cyano-1,2,5,6,7,8-hexahydro-isoquinol-1-one ( 13 ) or 1-amino-4-cyano-2,3,5,6,7,8-hexahydro-isoquinol-3-one ( 14 ). Compound 13 and alkaline formaldehyde react to cyanooctahydroisoquinoline-[2,3-c] [1,3,5]oxdiazin-6-one ( 17 ). 2-Cyanoethyl-cyclohexan-one-2-carboxamide ( 22 ), prepared by Michael-reaction from 4 and acrylonitrile, forms via nitrile carboxamide rearrangement 10-cyano-1,2,3,4,5,6,7,10-octahydroquinolin-2-one ( 24 ) and 2-(1′-cyano-cyclohexyl-2′-one)-propionic acid ( 25 ). Nucleophilic attack of the NH2-group at the cyanogroup of compound 22 forms 5-(spirocyclohexan-2′-one)-hexahydropyridin-2,6-dione ( 27 ).  相似文献   
102.
Oral Squamous Cell Carcinoma (OSCC) is the most common malignant cancer affecting the oral cavity. It is characterized by high morbidity and very few therapeutic options. Angiotensin (Ang)-(1-7) is a biologically active heptapeptide, generated predominantly from AngII (Ang-(1-8)) by the enzymatic activity of angiotensin-converting enzyme 2 (ACE 2). Previous studies have shown that Ang-(1-7) counterbalances AngII pro-tumorigenic actions in different pathophysiological settings, exhibiting antiproliferative and anti-angiogenic properties in cancer cells. However, the prevailing effects of Ang-(1-7) in the oral epithelium have not been established in vivo. Here, we used an inducible oral-specific mouse model, where the expression of a tamoxifen-inducible Cre recombinase (CreERtam), which is under the control of the cytokeratin 14 promoter (K14-CreERtam), induces the expression of the K-ras oncogenic variant KrasG12D (LSLK-rasG12D). These mice develop highly proliferative squamous papilloma in the oral cavity and hyperplasia exclusively in oral mucosa within one month after tamoxifen treatment. Ang-(1-7) treated mice showed a reduced papilloma development accompanied by a significant reduction in cell proliferation and a decrease in pS6 positivity, the most downstream target of the PI3K/Akt/mTOR signaling route in oral papilloma. These results suggest that Ang-(1-7) may be a novel therapeutic target for OSCC.  相似文献   
103.
The Synthesis of Octahydroquinazolinones and their Reaction with Peracid By reaction of cyclohexanone-2-carboxamide with ammonia and aldehydes, octahydroquinazolinones 2a–f , and with Schiff bases octahydroquinazolinones 3a–c are formed. 2-Hydroxycyclohexanone-2-carboxamide forms with ammonia and butyraldehyde the hydroxyocta-hydroquinazolinone 4 . Compound 2e reacts with monoperoxiphthalic acid to the hydroxyoxaziridine 5e which reacts with alkali hydroxide to compound 6. 8 yields with peroxy acid the hydroperoxy epoxide 9 .  相似文献   
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A new forage sorghum entitled Pnina was developed in Israel. Pnina, harvested at early milk (EM) and hard dough (HD) stages of maturity, was compared with commercial sorghum variety FS‐5 and a sorghum BMR/Sudan hybrid Nutriplus. Plants grew during summer and were irrigated with 190 mm water. Pnina was semi‐dwarf (1.35 m height) and absolutely resistant to lodging. The tall varieties FS‐5 and Nutriplus suffered at HD from high lodging. Pnina was more leafy than Nutriplus and FS‐5. The dry matter (DM) content of FS‐5 and Nutriplus were at EM below the level recommended for ensilage and elevated slightly at HD, whereas DM content of Pnina was higher. Crop yields of all varieties at HD were similar and ranged between 13.3 and 14.7 t ha?1 DM. Dry matter losses during ensilage and silage pH were similar in the three varieties at HD. In vitro DM digestibility of HD silages ranged between 62.5 and 67.1%. Neutral detergent fiber (NDF) content was higher in Pnina silages. Yields of digestible silage per hectare, were similar in the three varieties harvested at HD (8.4 to 8.8 t ha?1 DM); however, yield of digestible NDF per hectare was higher in Pnina. Data suggest that the new variety Pnina may have field advantage over the other varieties of this study. Copyright © 2005 Society of Chemical Industry  相似文献   
108.
为了提高织物手感的机械性能表征,把人看作是测量手感的机械传感器.由皮肤的机械性刺激感受器对织物刺激引起的触觉传入信息,可由应用显微神经检查法记录下来.实验结果突显出机械测量法的弱点.为了获得更多关于织物手感的专有信息,设备的传感器和信号处理已作了改进.  相似文献   
109.
Maize shows a significant genetic diversity, giving origin to a great number of varieties, hybrids, and genotypes. Recently, the pigmented corn varieties have received increased interest because of their anthocyanin contents. Although starch is the major component of the pigmented corn, only a few studies have been conducted on this constituent. The aim of this work was to evaluate the physicochemical properties and structural characteristics of starch isolated from six blue maize varieties grown in Mexico. The apparent amylose content ranged between 23.3 and 33.9%. The blue maize starches had an A‐type X‐ray diffraction pattern with similar crystallinity levels. Different gelatinization temperatures and enthalpy values were recorded, exhibiting different retrogradation tendencies (between 36.9 and 60.1%). The pasting parameters showed that the pasting temperature varied between 74.7 and 84.1°C, the maximum peak viscosity between 83.2 and 111.2 RVU units, and the setback viscosity between 26 and 38 RVU units. Structural differences were observed in the degree of branching, molar mass, and gyration radius. In view of their different physicochemical and structural characteristics, each of the blue maize starch varieties studied could have their own specific applications.  相似文献   
110.
This work explored the use of pregelatinised amaranth flour (PAF) as an oil substitute in the preparation of amaranth cakes. Amaranth flour was extruded to achieve approximately 50% gelatinisation, ground and sieved. The PAF was used to replace the oil in the cake preparation at levels 33, 66% and 100%. FTIR analysis of the cake formulations showed that PAF modified the molecular organisation of starch and proteins. The starch showed more hydrated structures, although less ordered. The proteins exhibited a significant reduction in the β structures and a marked increase of the side chains, probably caused by the interaction with amaranth starch. The in vitro digestibility of starch showed a slight increase with the addition of PAF. The slowly digesting starch fraction showed a visible decrease, reflecting the presence of starch chains more accessible to amylolysis. Instrumental texture revealed an increase (P < 0.05) in cake hardness with the addition of PAF, particularly for medium (66%) and high (100%) oil replacements. Sensory analysis showed that the perceived texture, flavour and colour were negatively affected by the addition of the pregelatinised flour. Overall, the sensory analysis indicated that cakes with low levels of PAF oil replacement may be acceptable to consumers.  相似文献   
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