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981.
Yuji Teramoto Noriaki Saigusa Yasuo Yoshida Seinosuke Ueda Kiyoshi Yoshizawa 《Journal of the Institute of Brewing》1994,100(1):3-6
Red rice sake was efficiently produced from unpolished red rice without cooking by use of rice koji prepared with shochu koji mold, Aspergillus kawachii, as saccharifying agent. A comparative study was made of red rice sake made with rice koji and red rice wine made with a preparation of glucoamylase known as Sumizyme. Red rice sake contained about 13% ethanol and its acidity was 8.6. Large amounts of volatile compounds, such as isobutyl alcohol and ethyl acetate, were found in the red rice sake. The red color of the red rice sake was more intense than that of the red rice wine. The quality of red rice sake was better than that of red rice wine, as assessed by gas chromatography, spectrophotometric analysis and organoleptic testing. In accordance with the traditional method for sake brewing, red rice, rice koji and tap water were added to the initial mash. The red color of the red rice sake made with these additions was more intense than that of red rice sake made without these additions. The rice wine was somewhat improved by these additions, as assessed by organoleptic testing. The body of the resultant rice wine was fortified with dextrin and its mild characteristics were derived from sugar and dextrin. 相似文献
982.
Yuji Teramoto Noriaki Saigusa Seinosuke Ueda Kiyoshi Yoshizawa 《Journal of the Institute of Brewing》1994,100(3):163-166
The quality of rice wine made from uncooked, unpolished aromatic red rice grain was improved by use of a commercial preparation of acid protease from Aspergillus niger during ethanol fermentation. The fermentation rate of the mash which contained the acid protease was much higher than that of mash that did not contain the preparation of acid protease. The rice wine made from uncooked, polished aromatic red rice, which usually had a less acceptable aroma, was improved by use of the preparation of acid protease, and large amounts of isobutyl alcohol, n-propyl alcohol and ethyl acetate were detected in the resultant rice wine. By contrast, the quality of rice wine made from the bran fraction of aromatic red rice was not improved by the preparation of acid protease. The polished rice fraction of aromatic red rice was affected by the acid protease and the aromatic quality of the rice wine was improved. The aromatic characteristics of red rice wine made from cooked, unpolished aromatic red rice grains, which was rather inferior in terms of both aroma and color, were also improved by the addition of the preparation of acid protease during ethanol fermentation. Thus acid protease has beneficial effects on the production of aromatic red rice wine. 相似文献
983.
Masaru Kaieda Taichi Samukawa Takeshi Matsumoto Kazuhiro Ban Akihiko Kondo Yuji Shimada Hideo Noda Fumiki Nomoto Koutaro Ohtsuka Eiji Izumoto Hideki Fukuda 《Journal of Bioscience and Bioengineering》1999,88(6):627
A new enzymatic method of synthesizing methyl esters from plant oil and methanol in a solvent-free reaction system was developed. It is anticipated that such plant oil methyl esters can be used as a biodiesel fuel in the future. Lipase from Rhizopus oryzae efficiently catalyzed the methanolysis of soybean oil in the presence of 4–30 wt% water in the starting materials; however the lipase was nearly inactive in the absence of water. The methyl ester (ME) content in the reaction mixture reached 80–90 wt% by stepwise additions of methanol to the reaction mixture. The kinetics of the reaction appears to be in accordance with the successive reaction mechanism. That is, the oil is first hydrolyzed to free fatty acids and partial glycerides, and the fatty acids produced are then esterified with methanol. Although R. oryzae lipase is considered to exhibit 1(3)-regiospecificity, a certain amount of 1,3-diglyceride was obtained during the methanolysis and hydrolysis of soybean oil by R. oryzae lipase solution. Therefore, the high ME content in the reaction mixture is probably attributable to the acyl migration from the sn-2 position to the sn-1 or sn-3 position in partial glycerides. 相似文献
984.
为探究超声处理对鹿茸菇贮藏品质的影响,本实验以新鲜鹿茸菇为试材,经超声(35 kHz、300 W)处理10 min后,测定鹿茸菇感官品质及能量代谢相关酶等相关指标。结果表明,超声处理相较于对照组可以维持鹿茸菇较高的亮度,并保持较高的总蛋白、抗坏血酸、谷胱甘肽含量,提高总超氧化物歧化酶活力,明显降低褐变程度。与对照组相比,贮藏期间超声处理组ATP、还原型烟酰胺腺嘌呤二核苷酸磷酸(nicotinamide adenine dinucleotide phosphate,NADPH)、氧化型NADPH(oxidized NADPH,NADP+)含量处于较高水平,6-磷酸葡萄糖脱氢酶、H+K+-ATPase、Na+K+-ATPase、Ca2+Mg2+-ATPase活力较高,表明超声处理延缓了鹿茸菇品质劣变现象。因此,超声保鲜可以为采后食用菌保鲜提供参考。 相似文献
985.
To promptly establish anaerobic ammonium oxidation (anammox) reactors, appropriate seeding sludge with high abundance and activity of anammox bacteria was selected by quantifying 16S rRNA gene copy numbers of anammox bacteria by real-time quantitative PCR (RTQ-PCR) and batch culture experiments. The selected sludge was then inoculated into up-flow fixed-bed biofilm column reactors with nonwoven fabric sheets as biomass carrier and the reactor performances were monitored over 1 year. The anammox reaction was observed within 50 days and a total nitrogen removal rate of 26.0 kg-Nm(-3)day(-1) was obtained after 247 days. To our knowledge, such a high rate has never been reported before. Hydraulic retention time (HRT) and influent NH(4)(+) to NO(2)(-) molar ratio could be important determinant factors for efficient nitrogen removal in this study. The higher nitrogen removal rate was obtained at the shorter HRT and higher influent NH(4)(+)/NO(2)(-) molar ratio. After anammox reactors were fully developed, the community structure, spatial organization and in situ activity of the anammox biofilms were analyzed by the combined use of a full-cycle of 16S rRNA approach and microelectrodes. In situ hybridization results revealed that the probe Amx820-hybridized anaerobic anammox bacteria were distributed throughout the biofilm (accounting for more than 70% of total bacteria). They were associated with Nitrosomonas-like aerobic ammonia-oxidizing bacteria (AAOB) in the surface biofilm. The anammox bacteria present in this study were distantly related to the Candidatus Brocadia anammoxidans with the sequence similarity of 95%. Microelectrode measurements showed that a high in situ anammox activity (i.e., simultaneous consumption of NH(4)(+) and NO(2)(-)) of 4.45 g-N of (NH(4)(+)+NO(2)(-))m(-2)day(-1) was detected in the upper 800 microm of the biofilm, which was consistent with the spatial distribution of anammox bacteria. 相似文献
986.
对比分析了中国GB 50009-2012、德国DIN 1055-4、美国ASCE/SEI 7-10、日本AIJ-2004、欧洲BS EN 1991-1-4:2005、加拿大NBC-2005、澳大利亚/新西兰AS/NZS 1170.2:2011、英国BS 6399-2:1997等规范中关于平屋盖围护结构外表面设计风压的有关规定。为便于比较,将各国规范风荷载标准值统一换算为外表面设计风压系数与基本风压乘积的形式。并且将外表面设计风压统一换算为与时距10min、重现期50a的基本风速相对应的值。针对外表面设计风压相关因素,对风向、风压分区、面积折减、建筑尺寸等进行了对比研究。最后,结合平屋盖风洞试验,探讨了外表面设计风压的具体取值建议。研究表明:平屋盖围护结构外表面设计风压的确定,建议考虑360°全风向;对屋盖边缘应进行风压分区,角部也应进行单独的风压分区;屋盖表面不同位置建议采用不同的面积折减公式;针对不同高度或宽高比建筑给定不同的外表面设计风压建议取值。 相似文献
987.
A flexible supporting structure that reduces seismic response of an arch is proposed. Topology and cross-sectional areas of the supporting structure modeled as a truss structure are optimized through two steps of static and dynamic optimization problems. In the first step, a flexible supporting structure that has diagonal displacement at the top under horizontal load is obtained by solving static optimization problems. Then, in the second step, the cross-sectional area of the flexible member is optimized to minimize the seismic response acceleration of the arch evaluated by the complete quadratic combination (CQC) method. Time-history seismic response analysis is carried out to show that the response in the normal direction of the roof successfully decreases due to flexibility of the supporting structure; in addition, installing passive energy dissipation devices into the flexible supporting structure is very effective in reducing the tangential response of the arch. 相似文献
988.
989.
Kyoko K. Bando Toshihide Kawai Kiyotaka Asakura Takashi Matsui Lionel Le Bihan Hiroyuki Yasuda Yuji Yoshimura S. Ted Oyama 《Catalysis Today》2006,111(3-4):199-204
Supported Pd–Pt catalysts are efficient for hydrodesulfurization (HDS) and hydrodearomatization (HDA) reactions of diesel fuel and their activity varied with the kinds of supports. Concerning HDA, alumina supported catalysts showed four times higher TOF (turn over frequency) than silica supported one. In order to elucidate the difference in activity, the structural analysis of the active phase was performed. After reduction pretreatment, relatively uniform and large metallic alloy Pd–Pt particles were formed on SiO2, whereas, Pd and Pt atoms formed rather segregated particles on Al2O3. Subsequent X-ray absorption of fine structure (XAFS) analysis under HDS conditions showed no contribution of sulfur for SiO2 supported catalyst, whereas, formation of sulfided metal species was observed in XAFS spectra for the Al2O3 supported catalyst. It is suggested that on Pd–Pt/SiO2, thin sulfide layer on the metal cluster surface blocked the active sites and lowered the HDA activity. Presence of partially sulfided phase originated from rather segregated structure like Pd–Pt/Al2O3 is thought to be requisite for high HDA activity. 相似文献
990.
介绍了合成拟除虫菊酯类杀虫剂的主要中间体之一--二氯菊酸的各种手性体的分离,拆分,并由此合成了创制农药-特效绿仙菊酯。 相似文献