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541.
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543.
Damaso Mônica C. T. Andrade Carolina M. M. C. Pereira Nei 《Applied biochemistry and biotechnology》2000,84(1-9):821-834
The production of cellulase-free end oxylanase by the thermophilic fungus Thermomyces lanuginosus was investigated insemisolid fermentation and liquid fermentation. Different process variables were investigated in semisolid
fermentation, employing corncobas the carbon source. The best results were with the following conditions: grain size=4.5 mm,
solid:liquid ratio=1:2, and inoculum size=20% (v/v). Corncob, xylan, and xylose were the best inducers for endoxylanase production.
Additionally, organic nitrogen sources were necessary for the production of high endoxylanase activities. The crude enzyme
had optimum activity at pH 6.0 and 75°C, displaying a high thermostability. The apparent K
25 and V
max were 1.77 mg of xylan/mL and 21.5 U/mg of protein, respectively. 相似文献
544.
Palma Marcia B. Pinto Annette L. Gombert Andreas K. Seitz Karina H. Kivatinitz Silvia C. Castilho Leda R. Freire Denise M. G. 《Applied biochemistry and biotechnology》2000,84(1-9):1137-1145
Lipase, protease, and amylase production by Penicillium restrictum in solid-state fermentation was investigated. The basal medium was an industrial waste of babassu oil (Orbignya oleifera) production. It was enriched with peptone, oliveoil, and Tween-80. The supplementation positively influenced both enzyme
production and fungal growth. Media enriched with Tween-80 provided the highest protease activity (8.6 U/g), whereas those
enriched with peptone and olive oil led to the highest lipase (27.8 U/g) and amylase (31.8 U/g) activities, respectively. 相似文献
545.
Inês C. Roberto Ismael M. de Mancilha Sunao Sato 《Applied biochemistry and biotechnology》1999,77(1-3):205-210
The fermentation kinetics for the conversion of rice straw hemicellulosic hydrolysate to xylitol by the yeast Candida guilliermondii was evaluated under batch conditions. The fermentation was accomplished in a 1 L working volume stirred-tank reactor with
aeration of 1.3 vvm and agitation of 300 rpm (kLa=15/h). The maximum specific rate of xylitol formation (0.12 g/g) was achieved when the specific growth rate was lowered
to 1/5 of its highest value. From analysis of the fermentation kinetics, a linear correlation between specific growth rate
(μx) and specific rate of xylitol formation (qp) was evident. Based on the Gaden model, this bioprocess was classified as growth-associated production and the relationship
between μx and qp can be described by the equation qp=6.31μx. 相似文献
546.
Hideo Tanaka Tomoharu Ebata Isamu Kuwahara Masaru Matsuo James C. Ogbonna 《Applied biochemistry and biotechnology》1999,80(1):51-64
Development and application of a system for real-time quantitative assessment of individual cell activities in a mixed culture
system was investigated. This was based on a concept that the activities of individual cells in a mixed culture can be assessed
if the cells are physically separated (in separate compartments) in a vessel while the culture conditions, including the broth
components, are maintained the same in all the compartments during the cultivation. On this basis, three different apparatus
(M-1, M-2, and M-3) were constructed using various types of membranes. In terms of mass transfer characteristics and membrane
fouling, the M-3 apparatus was the most effective system for analysis of mixed cultures at high cell densities. With the M-3
apparatus, the interrelationships between two alcohol-producing strains (Saccharomyces cerevisiae and Zymomonas mobilis) under anaerobic and aerobic conditions were studied. Under anaerobic condition, except for possible competition for nutrients,
there were no significant effects of the activities of one microorganism on the other. However, under aerobic condition, amensalism
was observed because acetaldehyde that was produced by Z. mobilis inhibited the growth of S. cerevisiae. 相似文献
547.
548.
Snezana Agatonovic-Kustrin Vladimir Gegechkori Dementyev Sergey Petrovich Kobakhidze Tamara Ilinichna David William Morton 《Molecules (Basel, Switzerland)》2021,26(22)
The aim of this study was to analyse the effect of spontaneous microbial maceration on the release and extraction of the flavonoids and phenolics from olive leaves. Bioprofiling based on thin-layer chromatography effect-directed detection followed by ATR-FTIR spectroscopy proved to be a reliable and convenient method for simultaneous comparison of the extracts. Results show that fermentation significantly enhances the extraction of phenolic compounds and flavonoids. The polyphenolic content was increased from 6.7 µg GAE (gallic acid equivalents) to 25.5 µg GAE, antioxidants from 10.3 µg GAE to 25.3 µg GAE, and flavonoid content from 42 µg RE (rutin equivalents) to 238 µg RE per 20 µL of extract. Increased antioxidant activity of fermented ethyl acetate extracts was attributed to the higher concentration of extracted flavonoids and phenolic terpenoids, while increased antioxidant activity in fermented ethanol extract was due to increased extraction of flavonoids as extraction of phenolic compounds was not improved. Lactic acid that is released during fermentation and glycine present in the olive leaves form a natural deep eutectic solvent (NADES) with significantly increased solubility for flavonoids. 相似文献
549.
番茄发酵饮料酒的工艺条件研究 总被引:4,自引:0,他引:4
吴旭 《新疆大学学报(理工版)》2005,22(1):73-75
本文对番茄饮料酒的发酵过程进行了研究。研究表明葡萄酒酵母较适合番茄发酵,并确定了较佳的工艺条件:发酵温度18℃。接种量3%和料液糖度17%. 相似文献
550.
Parise Adadi Alastair Harris Phil Bremer Patrick Silcock Austen R. D. Ganley Andrew G. Jeffs Graham T. Eyres 《Molecules (Basel, Switzerland)》2021,26(23)
This study investigated the impact of varying sound conditions (frequency and intensity) on yeast growth, fermentation performance and production of volatile organic compounds (VOCs) in beer. Fermentations were carried out in plastic bags suspended in large water-filled containers fitted with underwater speakers. Ferments were subjected to either 200–800 or 800–2000 Hz at 124 and 140 dB @ 20 µPa. Headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography-mass spectrometry (GC-MS) was used to identify and measure the relative abundance of the VOCs produced. Sound treatment had significant effects on the number of viable yeast cells in suspension at 10 and 24 h (p < 0.05), with control (silence) samples having the highest cell numbers. For wort gravity, there were significant differences between treatments at 24 and 48 h, with the silence control showing the lowest density before all ferments converged to the same final gravity at 140 h. A total of 33 VOCs were identified in the beer samples, including twelve esters, nine alcohols, three acids, three aldehydes, and six hop-derived compounds. Only the abundance of some alcohols showed any consistent response to the sound treatments. These results show that the application of audible sound via underwater transmission to a beer fermentation elicited limited changes to wort gravity and VOCs during fermentation. 相似文献