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991.
Mori S Yamasaki M Maruyama Y Momma K Kawai S Hashimoto W Mikami B Murata K 《Journal of Bioscience and Bioengineering》2004,98(5):391-393
NAD kinase from Mycobacterium tuberculosis (Ppnk) uses ATP or inorganic polyphosphate [poly(P)]. Ppnk overexpressed in Escherichia coli was purified and crystallized in the presence of NAD. Preliminary X-ray analysis of the resultant crystal indicate that the crystal belongs to hexagonal space group P6(2)22 and is holo-Ppnk complexed with NAD. 相似文献
992.
Species and muscle differences in L-carnitine levels in skeletal muscles based on a new simple assay 总被引:1,自引:0,他引:1
Shimada K Sakuma Y Wakamatsu J Fukushima M Sekikawa M Kuchida K Mikami M 《Meat science》2004,68(3):357-362
We have adapted the enzymatic method [Biochemical and Biophysical Research Communications 176 (3) (1991) 1617] for the safe and rapid assay of L-carnitine (L-CA) in skeletal muscle using a microplate reader. The concentration of L-CA in fresh semitendinosus muscle from broiler chicken, pig, beef cattle, deer, horse and goat muscle were 0.69, 1.09, 1.86-3.57, 4.57, 4.95 and 11.36 μmol/g wet weight, respectively. The animals which had higher concentration of L-CA, also had the highest amounts of myoglobin as an index to the redness of the muscle. Furthermore, we investigated this relationship between white muscle, M. pectoralis profundus, and red muscle, M. soleus, in laying hens. The L-CA and myoglobin concentration in red muscle were significantly higher than those in white muscle (p<0.01). These findings suggest that L-CA concentration in muscle is related to oxygen metabolism and to myofiber types. 相似文献
993.
994.
Sakai M Masai E Asami H Sugiyama K Kimbara K Fukuda M 《Journal of Bioscience and Bioengineering》2002,93(4):421-427
Two 2,3-dihydroxybiphenyl (23DHBP) dioxygenase genes, bphC1 and etbC involved in the degradation of polychlorinated biphenyl(s) (PCBs) have been isolated and characterized from a strong PCB degrader, Rhodococcus sp. RHA1. In this study, four new 23DHBP dioxygenase genes, designated as bphC2, bphC3, bphC4, and bphC5 were isolated from RHA1, and their nucleotide sequences were determined. Based on amino acid sequence similarities, all of the newly isolated bphC genes could be categorized into type I along with BphC1 and EtbC [Eltis, L.D. and Bolin, J.T., J. Bacteriol., 178, 5930-5937 (1996)]. Six bphC genes, including bphC1, etbC, and four new genes, were expressed in Escherichia coli to determine their substrate specificity. The activities of BphC2, BphC3, BphC4, and BphC5 were found to be specific to 23DHBP, while BphC1 and EtbC exhibited activities towards compounds other than 23DHBP, including catechol (CAT) and 3-methylcatechol (3MC). RNA slot blot hybridization analysis indicated that only bphC5 was transcribed among the newly isolated bphC in RHA1 cells grown on biphenyl and ethylbenzene. The nucleotide sequence of the flanking region of each bphC revealed a homolog of the 2-hydroxy-6-oxo-6-phenylhexa-2,4-dienoate (HOPD) hydrolase gene, bphD, just upstream of bphC5. The bphC5 and putative bphD genes may constitute an operon and play a role in the degradation of biphenyl and PCBs together with bphC1 and etbC. In contrast, the bphC2, bphC3, and bphC4 genes may not be involved in biphenyl and PCB degradation. 相似文献
995.
Hideo Kobayashi Shinsuke Sakai Masayuki Asano Katsumasa Miyazaki Takeharu Nagasaki Yoshiaki Takahashi 《International Journal of Pressure Vessels and Piping》2000,77(14-15)
This paper introduces a handbook, which is edited by the High Pressure Institute of Japan to support engineers who evaluate flaws detected in nuclear power components according to the Japanese fitness-for-service code. The handbook is written in Japanese and contains basic information on fracture mechanics as well as the specific flaw evaluation procedures and material properties data stipulated in the code. The main features of the handbook are summarized in the paper. 相似文献
996.
Demineralisation of whey by a combination of nanofiltration and anion‐exchange treatment: a preliminary study 下载免费PDF全文
Teiichiro Okawa Masayuki Shimada Yoshihiko Ushida Nobuo Seki Naoki Watai Masatoshi Ohnishi Yoshitaka Tamura Akira Ito 《International Journal of Dairy Technology》2015,68(4):478-485
Demineralisation is an important process for the utilisation of whey in the food industry. Sodium (Na+) and potassium (K+) ions pass through nanofiltration (NF) membranes in ion pairs with chloride (Cl?) to maintain electroneutrality, but NF processing can only partially remove these ions from whey, because the total Na and K content of whey generally exceeds the Cl content. In this work, a preliminary study of a new demineralisation method was made. A reconstituted sweet whey powder solution was first treated by Cl‐form anion‐exchange resin to increase the molar ratio of Cl to Na and K from ~0.5 to ~1.0. Subsequently, NF removed >90% of Na and K from the anion‐exchange treated whey compared with <60% from the control whey. This new process could be useful for producing 70% demineralised whey with very low levels of the monovalent ions Na+, K+ and Cl?. 相似文献
997.
Investigation of beer‐spoilage ability of Dekkera/Brettanomyces yeasts and development of multiplex PCR method for beer‐spoilage yeasts 下载免费PDF全文
Satoshi Shimotsu Shizuka Asano Kazumaru Iijima Koji Suzuki Hiromi Yamagishi Masayuki Aizawa 《Journal of the Institute of Brewing》2015,121(2):177-180
There have been many beer‐spoilage incidents caused by wild yeasts. Saccharomyces cerevisiae, Dekkera anomala and D. bruxellensis have been recognized as beer‐spoilage yeasts in the brewing industry. In contrast, the beer spoilage ability of Brettanomyces custersianus has not been well characterized, although this species was isolated from beer. In this study, the beer‐spoilage ability of currently described Dekkera/Brettanomyces yeast species was investigated. As a consequence, D. anomala, D. bruxellensis and B. custersianus were shown to grow in commercial beers. On the other hand, the remaining two Brettanomyces species, B. naardenensis and B. nanus, did not grow in beer. These results indicate that B. custersianus should be recognized as a beer‐spoilage species, in addition to S. cerevisiae, D. anomala, and D. bruxellensis. Therefore we developed multiplex polymerase chain reaction (PCR) for the simultaneous detection and identification of B. custersianus and the other beer‐spoilage yeast species. For this purpose, PCR primers were designed in the internal transcribed spacer region or 26S rDNA, and each PCR product was made in different sizes to easily discriminate the species from electrophoretic results. Specificity, reactivity and sensitivity of the designed primers were evaluated. As a result, the developed multiplex PCR method was shown to have high specificity and reactivity, and therefore was considered as an effective tool to identify beer‐spoilage yeast species. This tool can contribute to microbiological quality assurance in breweries. Copyright © 2015 The Institute of Brewing & Distilling 相似文献
998.
999.
1000.
Recently, people around the world have actively made efforts to conserve energy in residential homes as a countermeasure against global warming. The awareness of the importance of energy saving has continued to grow in Japan since the Great East Japan Earthquake in March 2011. The interest in cross-ventilation for air conditioning energy saving in summer is especially increasing. Japan's climate features high temperatures and humidity, and it is a country in which people used cross-ventilation in their homes during summer and the middle season earlier. However, due to changes in modern society, including the progress in air-conditioning facilities, the focus on an environmentally conscious house design was lost. Therefore, studies about cross-ventilation have not been conducted in recent years. This study reconsidered the value of Japanese traditional houses and evaluated the effect of the planar-shaped house in cross-ventilation. It also surveyed the heat-insulating effect of a Taiko-shoji that was developed from an ordinary shoji screen used in Japanese traditional houses. The results show that a skylight opening increased the cross-ventilation air volume and that the shape worked effectively as a wind catcher without any special equipment. Moreover, the study found that the installment of a Taiko-shoji had a significant effect on heat insulation in summer and winter. 相似文献