全文获取类型
收费全文 | 714篇 |
免费 | 14篇 |
专业分类
电工技术 | 22篇 |
综合类 | 1篇 |
化学工业 | 104篇 |
金属工艺 | 13篇 |
机械仪表 | 22篇 |
建筑科学 | 13篇 |
能源动力 | 30篇 |
轻工业 | 71篇 |
水利工程 | 1篇 |
石油天然气 | 1篇 |
无线电 | 52篇 |
一般工业技术 | 130篇 |
冶金工业 | 192篇 |
原子能技术 | 10篇 |
自动化技术 | 66篇 |
出版年
2021年 | 12篇 |
2020年 | 6篇 |
2019年 | 4篇 |
2018年 | 6篇 |
2017年 | 5篇 |
2016年 | 13篇 |
2015年 | 6篇 |
2014年 | 17篇 |
2013年 | 44篇 |
2012年 | 24篇 |
2011年 | 29篇 |
2010年 | 14篇 |
2009年 | 21篇 |
2008年 | 21篇 |
2007年 | 21篇 |
2006年 | 22篇 |
2005年 | 21篇 |
2004年 | 14篇 |
2003年 | 11篇 |
2002年 | 20篇 |
2001年 | 22篇 |
2000年 | 18篇 |
1999年 | 24篇 |
1998年 | 73篇 |
1997年 | 29篇 |
1996年 | 34篇 |
1995年 | 22篇 |
1994年 | 17篇 |
1993年 | 16篇 |
1992年 | 15篇 |
1991年 | 7篇 |
1990年 | 16篇 |
1989年 | 9篇 |
1988年 | 6篇 |
1987年 | 7篇 |
1986年 | 11篇 |
1985年 | 9篇 |
1984年 | 4篇 |
1983年 | 4篇 |
1982年 | 4篇 |
1981年 | 4篇 |
1980年 | 7篇 |
1979年 | 12篇 |
1978年 | 3篇 |
1977年 | 3篇 |
1976年 | 11篇 |
1975年 | 4篇 |
1973年 | 2篇 |
1970年 | 1篇 |
1967年 | 1篇 |
排序方式: 共有728条查询结果,搜索用时 15 毫秒
721.
Koji Fujisato Hiroto Habu Atsumi Miyake Keiichi Hori Alexander B. Vorozhtsov 《Propellants, Explosives, Pyrotechnics》2014,39(4):518-525
The thermal decomposition behavior and combustion characteristics of mixtures of ammonium dinitramide (ADN) with additives were studied. Micrometer‐sized particles of Al, Fe2O3, TiO2, NiO, Cu(OH)NO3, copper, CuO, and nanometer‐sized particles of aluminum (Alex) and CuO (nano‐CuO) were employed. The thermal decomposition was measured by TG‐DTA and DSC. The copper compounds and NiO lowered the onset temperature of ADN decomposition. The heat value of ADN with Alex was larger than that of pure ADN in closed conditions. The burning rates and temperature of the pure ADN and ADN/additives mixtures were measured. CuO and NiO enhance the burning rate, particularly at pressures lower than 1 MPa, because of the catalyzed decomposition in the condensed phase; the other additives lower the burning rate. This negative effect on the burning rate is explained based on the surface temperature measurements by a physicochemical mechanism, which involves a chemical reaction, a phase change of the ammonium nitrate, and the blown‐off droplets of the condensed phase. 相似文献
722.
Nishijima K Esaka K Ibuki H Ono K Miyake K Kamihira M Iijima S 《Journal of Bioscience and Bioengineering》2003,95(6):612-617
Many chemicals that are not structurally related to estrogen have estrogen-like activity. In this study, we tried to apply a quail embryo culture system for assessing the in vivo effects of such chemicals on the development of quail embryos. Beta-estradiol induced feminization of the gonads of genetically male embryos, which was confirmed by the increase in the size of the left gonad and female-specific aromatase expression, while male-specific SOX9 expression was not affected. Nonylphenol, which has a weak estrogenic activity, reduced the viability and body weight of embryos. Simultaneously, several genetically male embryos were feminized in terms of gonadal size and aromatase expression. These results indicate that the avian embryo culture system was useful for evaluating endocrine disrupters. 相似文献
723.
Hiroyuki Kataoka Mina Miyake Sachiko Nishioka Tomoko Matsumoto Keita Saito Kurie Mitani 《Molecular nutrition & food research》2010,54(7):1039-1048
Heterocyclic amines (HCAs) are mutagenic and carcinogenic compounds found in cooked meat and fish. Although HCAs are known to form adducts with protein after metabolic activation, adduct formation during cooking has not been elucidated. In this study, we showed that 2‐amino‐1‐methyl‐6‐phenylimidazo[4,5‐b]pyridine (PhIP) is released from high molecular weight compounds by acid or enzymatic hydrolysis of cooked foods. Formation of free and protein adduct forms of PhIP was dependent on cooking temperature and time, and PhIP–protein adducts were estimated to form after formation of free PhIP. We also demonstrated that PhIP–protein adduct is formed by heating of PhIP and albumin as a model protein. A new adduct peak including [M+H]+ (m/z=225) of PhIP as a fragment ion was detected in the high molecular weight fraction of heat‐treated protein by LC–MS analysis. From model experiments by heating of PhIP and amino acids, the adduct was estimated to be produced by condensation of the amino group of PhIP and the carboxyl group of protein. PhIP–protein adducts were detected in several cooked meat and fish at ng/g food level as PhIP content. These results suggest that food‐borne protein adducts of HCAs may influence human HCA exposure and carcinogenic risk. 相似文献
724.
Mahesh Kodoth Shu Aoyama Junji Sakamoto Naoya Kasai Tadahiro Shibutani Atsumi Miyake 《International Journal of Hydrogen Energy》2018,43(52):23409-23417
Hydrogen, as a future energy carrier, is receiving a significant amount of attention in Japan. From the viewpoint of safety, risk evaluation is required in order to increase the number of hydrogen refueling stations (HRSs) implemented in Japan. Collecting data about accidents in the past will provide a hint to understand the trend in the possibility of accidents occurrence by identifying its operation time However, in new technology; accident rate estimation can have a high degree of uncertainty due to absence of major accident direct data in the late operational period. The uncertainty in the estimation is proportional to the data unavailability, which increases over long operation period due to decrease in number of stations. In this paper, a suitable time correlation model is adopted in the estimation to reflect lack (due to the limited operation period of HRS) or abundance of accident data, which is not well supported by conventional approaches. The model adopted in this paper shows that the uncertainty in the estimation increases when the operation time is long owing to the decreasing data. 相似文献
725.
726.
Vasilyeva L Miyake M Khatipov E Wakayama T Sekine M Hara M Nakada E Asada Y Miyake J 《Journal of Bioscience and Bioengineering》1999,87(5):619-624
A stable mutant of the photosynthetic bacterium Rhodobacter sphaeroides with an altered light-harvesting (LH) system (P3 mutant) was obtained by UV irradiation and characterized. The mutant exhibited a 2.7-fold decrease in the core antennal (LH1) content and 1.6-fold increase in peripheral antennal (LH2) content compared to the wild-type strain. The H2 evolution rates in the P3 mutant under 800- and 850-nm light, corresponding to the absorption maxima of LH2, were 1.5 times higher than in the wild-type strain. The wild-type absorption spectrum was restored in the P3 mutant when a 1.1-kb PCR-amplified fragment containing the puf promoter and pufQBA genes was ligated into a pRK-415 derivative and introduced into it. The transformant showed lower H2 production rates at 800 and 850 nm than the P3 strain carrying the control plasmid, indicating that the accelerated H2 production in the P3 mutant was a result of alterations in the LH system. 相似文献
727.
Yuko Miyake Kazuhisa Yokomizo Narihide Matsuzaki 《Journal of the American Oil Chemists' Society》1998,75(1):15-19
High-resolution 1H nuclear magnetic resonance (1H NMR) has been found to be an effective tool for the direct, rapid, and automated determination of the iodine value (IV)
of vegetable oils, including hydrogenated oils (IV=45.9–140.2). The total time required to obtain the 1H NMR data is about 3 min per sample. The IV is calculated from the number of double-bonded protons and the average molecular
weight derived directly from the spectrum. The average of olefinic protons and allylic plus divinyl protons area was used
to calculate the absolute number of double-bonded protons. The 1H NMR results were compared with those obtained by the traditional Wijs-cyclohexane methods. The correlation coefficient between
traditional IV and the novel 1H NMR method was r
2=0.9994 for the regression equation Y=0.9885X + 2.8084, where X was the result given by the traditional method. With the proposed regression equation, IV calculated by the 1H NMR method was within an error of ± 1 unit of the result obtained by the traditional method. The proposed method is practically
viable if one can afford to have the NMR system. 相似文献
728.