全文获取类型
收费全文 | 248篇 |
免费 | 9篇 |
专业分类
电工技术 | 14篇 |
综合类 | 1篇 |
化学工业 | 61篇 |
金属工艺 | 9篇 |
机械仪表 | 8篇 |
建筑科学 | 8篇 |
能源动力 | 13篇 |
轻工业 | 24篇 |
水利工程 | 1篇 |
石油天然气 | 1篇 |
无线电 | 8篇 |
一般工业技术 | 45篇 |
冶金工业 | 24篇 |
原子能技术 | 14篇 |
自动化技术 | 26篇 |
出版年
2023年 | 1篇 |
2022年 | 3篇 |
2021年 | 6篇 |
2020年 | 4篇 |
2019年 | 2篇 |
2018年 | 4篇 |
2017年 | 3篇 |
2016年 | 7篇 |
2015年 | 6篇 |
2014年 | 5篇 |
2013年 | 14篇 |
2012年 | 7篇 |
2011年 | 8篇 |
2010年 | 17篇 |
2009年 | 29篇 |
2008年 | 9篇 |
2007年 | 8篇 |
2006年 | 10篇 |
2005年 | 7篇 |
2004年 | 10篇 |
2003年 | 10篇 |
2002年 | 5篇 |
2001年 | 2篇 |
2000年 | 3篇 |
1999年 | 3篇 |
1998年 | 9篇 |
1997年 | 9篇 |
1996年 | 7篇 |
1995年 | 2篇 |
1994年 | 6篇 |
1993年 | 6篇 |
1992年 | 4篇 |
1991年 | 2篇 |
1990年 | 1篇 |
1989年 | 3篇 |
1988年 | 4篇 |
1987年 | 2篇 |
1986年 | 1篇 |
1985年 | 4篇 |
1984年 | 1篇 |
1983年 | 3篇 |
1982年 | 3篇 |
1981年 | 1篇 |
1979年 | 1篇 |
1978年 | 1篇 |
1977年 | 2篇 |
1976年 | 2篇 |
排序方式: 共有257条查询结果,搜索用时 15 毫秒
71.
Taku Uemura Shizuka Hirai Noriko Mizoguchi Tsuyoshi Goto Joo‐Yong Lee Keiko Taketani Yuki Nakano Jinji Shono Shohei Hoshino Nobuaki Tsuge Toshihiko Narukami Nobuyuki Takahashi Teruo Kawada 《Molecular nutrition & food research》2010,54(11):1596-1608
In obesity, adipocyte hypertrophy and chronic inflammation in adipose tissues cause insulin resistance and type‐2 diabetes. Trigonella foenum‐graecum (fenugreek) can ameliorate hyperglycemia and diabetes. However, the effects of fenugreek on adipocyte size and inflammation in adipose tissues have not been demonstrated. In this study, we determined the effects of fenugreek on adipocyte size and inflammation in adipose tissues in diabetic obese KK‐Ay mice, and identified the active substance in fenugreek. Treatment of KK‐Ay mice with a high fat diet supplemented with 2% fenugreek ameliorated diabetes. Moreover, fenugreek miniaturized the adipocytes and increased the mRNA expression levels of differentiation‐related genes in adipose tissues. Fenugreek also inhibited macrophage infiltration into adipose tissues and decreased the mRNA expression levels of inflammatory genes. In addition, we identified diosgenin, a major aglycone of saponins in fenugreek to promote adipocyte differentiation and to inhibit expressions of several molecular candidates associated with inflammation in 3T3‐L1 cells. These results suggest that fenugreek ameliorated diabetes by promoting adipocyte differentiation and inhibiting inflammation in adipose tissues, and its effects are mediated by diosgenin. Fenugreek containing diosgenin may be useful for ameliorating the glucose metabolic disorder associated with obesity. 相似文献
72.
Polymer-dispersed perylene di-imide dye photodegradation is investigated by monitoring the fluorescence intensity as a function of 532 nm laser pulses. Anaerobically irradiated polymer-dye films exhibited an accelerated decrease in fluorescence intensity, which was partially recovered upon exposure to oxygen. Decelerated photodegradation rates were observed for perylene di-imide ethanol solutions upon the addition of a singlet oxygen quenching antioxidant. These observations suggest reversible photoreduction and type II photo-oxidation as important photodegradation mechanisms. Type II photo-oxidation for perylene red 532 nm irradiation is supported by a singlet oxygen quantum yield of 0.09+/-0.03, determined via detection of time-resolved O2 (a1delta(g) --> X3sigma(g)-) infrared phosphorescence. 相似文献
73.
Makoto Takemori 《Ceramics International》2009,35(5):1747-1755
This report is a continuation of Part I of my studies of a non-aqueous sol–gel silica coating deposited on stainless steel SUS304. Part I discussed the microscopic observation of cracks, ridges and interlayers within the resulting silica coatings, and provided limited insight into their respective mechanisms of formation. This report provides further explanation for the mechanisms of these processes, as evidenced by spectroscopic and nano-indentation analyses of the coatings. Specifically, the coatings were analyzed by Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, X-ray diffraction, and Auger electron spectroscopy. These results are discussed along with those obtained in Part I to further assess the mechanisms of crack formation in the coatings, and it was found that coating shrinkage and tension most likely caused crack formation. It seems that the O-deficient interlayers were formed under a mild oxidation condition existed around the silica/SUS304 interface during ~500 °C annealing. Additionally, nano-indentation analysis indicated that the coatings were compact, but the coatings’ hardness was intermediate. Suggestions for improvement of sol–gel silica coatings on stainless steel are also provided. 相似文献
74.
Hiromi Matsuhashi Koji Nagashima Nobuaki Naijo Hirofumi Aritani 《Topics in Catalysis》2010,53(7-10):659-663
Solid bases comprising MgO covered with Al2O3 were prepared by decomposition of Al(OCH(CH3)2)3 over Mg(OH)2 in ethyl acetate. Catalysts containing more than 10 mol% Al were insoluble in acetone. Aluminum occupied mainly octahedral sites in the low content range; tetrahedral structure being the principal one in the high range. 相似文献
75.
Estrogen receptor binding assay method for endocrine disruptors using fluorescence polarization 总被引:1,自引:0,他引:1
Ohno K Fukushima T Santa T Waizumi N Tokuyama H Maeda M Imai K 《Analytical chemistry》2002,74(17):4391-4396
A rapid, simple and nonhazardous assay method for endcrine disruptors was developed using an estrogen receptor (ER) and fluorescence polarization (FP). Among the fluorescent compounds, the 17alpha-fluorescein-labeled estradiol derivative was selected as the most suitable ligand for the ER binding assay, since it showed the highest affinity to ER. In the Scatchard plot analysis, its convex curve exhibited a positive cooperative binding, indicating the induction of a conformational change of the ER with the binding of the ligand to form a dimer and to increase the affinity for the additional ligand. On the basis of the Hill plot analysis, its dissociation constant and Hill coefficient were 10.4 nM and 1.63, respectively. A competitive binding assay with an unlabeled 17beta-estradiol (E2) yielded an IC50 value of 2.82 nM and a Hill coefficient of 1.67, thus providing a Ki value of 0.65 nM. In the same manner, the Hill coefficients for estrone, estriol, diethylstilbestrol, and tamoxifen were determined to be 0.99, 1.17, 1.59, and 2.44, respectively. 相似文献
76.
We describe a technique for noncontact velocity measurement by using double-exposure speckle-pattern techniques with optical signal processing. The two speckle patterns are recorded on a ferroelectric liquid-crystal (FLC) spatial light modulator (SLM), which is a bistable optically addressed SLM, and the composite pattern is then analyzed by an optical system similar to a joint transform correlator, in which another FLC-SLM and a position-sensitive detector are used. We show that the performance of the system can be significantly improved by adjusting the time between exposures using a real-time feedback system that is based on the position of the correlation spot in the output plane. 相似文献
77.
Mayuko Ikarashi Junko Tsuchida Masayuki Nagahashi Shiho Takeuchi Kazuki Moro Chie Toshikawa Shun Abe Hiroshi Ichikawa Yoshifumi Shimada Jun Sakata Yu Koyama Nobuaki Sato Nitai C. Hait Yiwei Ling Shujiro Okuda Kazuaki Takabe Toshifumi Wakai 《International journal of molecular sciences》2021,22(24)
Although numerous experiments revealed an essential role of a lipid mediator, sphingosine-1-phosphate (S1P), in breast cancer (BC) progression, the clinical significance of S1P remains unclear due to the difficulty of measuring lipids in patients. The aim of this study was to determine the plasma concentration of S1P in estrogen receptor (ER)-positive BC patients, as well as to investigate its clinical significance. We further explored the possibility of a treatment strategy targeting S1P in ER-positive BC patients by examining the effect of FTY720, a functional antagonist of S1P receptors, on hormone therapy-resistant cells. Plasma S1P levels were significantly higher in patients negative for progesterone receptor (PgR) expression than in those positive for expression (p = 0.003). Plasma S1P levels were also significantly higher in patients with larger tumor size (p = 0.012), lymph node metastasis (p = 0.014), and advanced cancer stage (p = 0.003), suggesting that higher levels of plasma S1P are associated with cancer progression. FTY720 suppressed the viability of not only wildtype MCF-7 cells, but also hormone therapy-resistant MCF-7 cells. Targeting S1P signaling in ER-positive BC appears to be a possible new treatment strategy, even for hormone therapy-resistant patients. 相似文献
78.
Nobuaki Kitazawa S. Miyagawa K. Date W. Aroonjaeng M. Aono Y. Watanabe 《Journal of Materials Science》2009,44(18):4999-5003
Dye-doped deoxyribonucleic acid–surfactant films have been prepared by an intercalation method and their optical properties
have been investigated. Coumarin 1 (C1), known as a neutral laser dye, can be successfully incorporated in deoxyribonucleic
acid-surfactant films by immersing them in aqueous dye solution. About 6 wt% C1 can be doped in samples when the immersion
time is 86400 s. C1-doped samples show pronounced optical absorption and photoluminescence bands. Not only hydrophobic–hydrophobic
interactions but also molecular structures of dyes play prominent roles in the formation of neutral dye-doped deoxyribonucleic
acid-surfactant films. It is surmised that C1 stays inside the double helix of deoxyribonucleic acid (DNA) and/or between
the alkyl groups of surfactants. 相似文献
79.
Hiroshi Hirata Yuuta Iwama Shigeo Kuroda Takemori Fukuda Tokio Hagiwara 《Reactive and Functional Polymers》2009,69(3):170-175
A novel bifunctional monomer, (4-maleimidophenyl)oxirane (MAPO), with very reactive maleimido and epoxy groups, was prepared through the selective oxidation of the two carbon–carbon double bonds of N-(4-vinylphenyl)maleimide. Either of the two different polymerizable groups (vinylene of the maleimide moiety and the mono-substituted epoxide) of MAPO was able to be selectively polymerized by choosing the polymerization method. For radical polymerization, MAPO gave poly{p-[1,2-(epoxyethyl)phenyl]maleimide} (PEPM) with dense pendent epoxy groups in 76% yield without cross-linking. MAPO also gave poly(maleimidostyrene oxide) (PMSO) with dense pendent maleimido groups through cationic polymerization in 60% yield. On the other hand, anionic polymerization with an of MAPO produced only insoluble gel-like materials due to unselective polymerization of the two polymerizable groups (Scheme 1). The vinylene group of the maleimide moiety in PMSO easily reacted with the mercapto group, and the ring-opening reaction of the epoxy groups in PEPM with amino groups took place. 相似文献
80.
Kiyoshi Takigawa Naotaka Okada Nobuaki Kuwabara Akio Kitamura Fumio Yamamoto 《Solar Energy Materials & Solar Cells》2003,75(3-4):547-555
It is a disadvantage that PV power generation is only useful for clear daytime. However, a new 24 hours of application in an extended area can be added by active utilization of potential ability of PV power conditioner. For this purpose, a new multi-functional power conditioner was developed, which has a smoothing function to reduce PV output variation and load fluctuation, and also has additional function to compensate harmonics current and reactive power caused by customer's load.As a result of indoor testing, a reduction rate of around
for harmonics current and reactive power were achieved. In addition, the reduction rate around
for smoothing of PV output variation and load fluctuation were verified.The work was promoted by NEDO as part of the New Sunshine Project in Japan. 相似文献