全文获取类型
收费全文 | 540篇 |
免费 | 22篇 |
国内免费 | 3篇 |
专业分类
电工技术 | 50篇 |
化学工业 | 187篇 |
金属工艺 | 16篇 |
机械仪表 | 10篇 |
建筑科学 | 10篇 |
矿业工程 | 1篇 |
能源动力 | 21篇 |
轻工业 | 32篇 |
无线电 | 28篇 |
一般工业技术 | 83篇 |
冶金工业 | 46篇 |
原子能技术 | 18篇 |
自动化技术 | 63篇 |
出版年
2023年 | 6篇 |
2022年 | 18篇 |
2021年 | 29篇 |
2020年 | 13篇 |
2019年 | 7篇 |
2018年 | 12篇 |
2017年 | 5篇 |
2016年 | 19篇 |
2015年 | 18篇 |
2014年 | 28篇 |
2013年 | 38篇 |
2012年 | 27篇 |
2011年 | 45篇 |
2010年 | 26篇 |
2009年 | 35篇 |
2008年 | 25篇 |
2007年 | 24篇 |
2006年 | 14篇 |
2005年 | 15篇 |
2004年 | 17篇 |
2003年 | 9篇 |
2002年 | 13篇 |
2001年 | 6篇 |
2000年 | 6篇 |
1999年 | 7篇 |
1998年 | 16篇 |
1997年 | 11篇 |
1996年 | 12篇 |
1995年 | 9篇 |
1994年 | 7篇 |
1993年 | 16篇 |
1992年 | 2篇 |
1991年 | 1篇 |
1990年 | 3篇 |
1989年 | 3篇 |
1988年 | 2篇 |
1987年 | 1篇 |
1986年 | 2篇 |
1985年 | 3篇 |
1983年 | 1篇 |
1981年 | 2篇 |
1980年 | 2篇 |
1979年 | 1篇 |
1977年 | 1篇 |
1976年 | 4篇 |
1975年 | 1篇 |
1974年 | 2篇 |
1973年 | 1篇 |
排序方式: 共有565条查询结果,搜索用时 15 毫秒
101.
To assess immunoglobulin production in vivo, the numbers of immunoglobulin-secreting cells were measured in uncultured peripheral blood mononuclear cells (PBMCs) of patients with primary immunoglobulin deficiency. The numbers of immunoglobulin-secreting cells were found to be variable, and they were well correlated with the serum concentrations of all three major immunoglobulin classes. Our results suggest that measurement of immunoglobulin-secreting cells in PBMCs is useful in the assessment of the ability to produce immunoglobulin in vivo. 相似文献
102.
Hisayoshi Mitamura Seiichiro Matsumoto Takashi Miyazaki Timothy J. White Kiyoshi Nukaga Yoshihiro Togashi Tamio Sagawa Shingo Tashiro Desmond M. Levins Akira Kikuchi 《Journal of the American Ceramic Society》1990,73(11):3433-3441
The polyphase titanate ceramic containing sodium-rich simulated high-level nuclear waste was doped with 0.69 wt% of 244 Cm to accelerate long-term self-irradiation due to α decays. α autoradiography showed that α emissions were almost uniformaly distributed throughout the curium-doped samples on a >20-μm scale although micropore surfaces and titanium oxide agglomerates were free of α-emitting nuclides. The phase assemblage of the curium-doped titanate ceramic included freudenbergite and loveringite in addition to the more abundant oxide phases: hollandite, perovskite, and zirconolite. Accumulation of α decays was accompanied by a gradual decrease in density. The increment of density was – 1% after an equivalent age of 5000 yr. Leach tests showed a slight trend toward higher total release of curium with equivalent age. The release of soluble nonradioactive elements (e.g., Na, Cs, Sr, and Ca) in the oldest specimens (equivalent age, 2000 yr) varied from specimen to specimen but, on average, were higher than specimens that had suffered a lower radiation dose. 相似文献
103.
Y Iedokoro M Hioki T Mishima J Kawamura S Yamagishi K Orii Y Yamashita T Hirata S Masuda S Tanaka 《Canadian Metallurgical Quarterly》1998,65(5):413-415
Gene therapy has been proposed for a wide variety of human conditions including monogenic disorders, such as the haemoglobinopathies and immunodeficiency syndromes, cancer and many other diseases. Prerequisites for the success of this approach include the ability to deliver the therapeutic gene intact to the target cell, persistent levels of transgene expression sufficient to correct the disease phenotype, lack of unwanted side-effects associated with vector exposure or gene transfer and relative simplicity allowing the widespread use of this methodology. Although substantial progress has been made in animal models since the inception of genetic therapy in the early 1980s, significant obstacles remain for human therapy, most notably in the area of vector development. The first generation of gene therapy vectors has failed to overcome many of the biological hurdles cited above necessitating the development of alternate means of gene delivery and expression. 相似文献
104.
S Yamaguchi A Sakai T Fukao A Wakazono T Kuwahara T Orii T Hashimoto 《Canadian Metallurgical Quarterly》1993,33(5):429-432
The possibility of identifying heterozygotes of 3-ketothiolase deficiency, an inborn error of metabolism caused by a defect of mitochondrial acetoacetyl-CoA thiolase (T2), was tested in seven unrelated families by using enzymatic assay of thiolase activity and immunoblot analysis. The ratio of acetoacetyl-CoA thiolase activities, in the presence and absence of K+ ion (+K/-K ratio), in fibroblasts from 15 normal controls was around 2.0 (1.8 to 2.4), whereas the +K/-K ratio in eight patients was always 1.0. The ratio for the 13 obligate carriers ranged from 1.4 to 1.9, causing a minor overlap with control. Identification of heterozygote cells by immunoblot analysis, using anti-T2 antibody alone as a probe, was difficult, as previously reported. We therefore carried out immunoblot analysis, using as probes a mixture of anti-T2 antibody and the antibody against mitochondrial 3-ketoacyl-CoA thiolase (T1), another mitochondrial thiolase, and determined the ratio of the intensities of the T2 and T1 bands (T2/T1 ratio) using a densitometer. When the T2/T1 ratio was calculated, there was no overlap between the heterozygotes and normal controls. Hence, the heterozygotes can be unambiguously identified using this method. The thiolase activities and T2/T1 proteins in immunoblotting were detectable in peripheral lymphocytes, rectal mucosa, amniocytes, and liver. Thus, the postnatal diagnosis of 3-ketothiolase deficiency can be readily made using lymphocytes or rectal mucosa. The applicability of these methods in amniocytes indicates that prenatal diagnosis of this disease should be possible. 相似文献
105.
Fabrication of Bi2Sr2CaCu2Ox films on metal substrates by the chemical process using metal alkoxides
The formation behaviour of Bi2Sr2CaCu2Ox from compounds prepared by hydrolysis of metal alkoxides was studied and Bi2Sr2CaCu2Ox films on metal substrates were fabricated using a metal alkoxide solution. Bi2Sr2CaCu2Ox was formed through intermediate phases such as Bi2Sr2Cu1Ox, Bi2CuO4, SrCO3, CaCO3 and CuO. Bi2CuO4 was initially formed with SrCO3, CaCO3 and CuO, and then reacted with SrCO3 to form Bi2Sr2Cu1Ox. Bi2Sr2Cu1Ox reacted with CaCO3 and CuO to give Bi2Sr2CaCu2Ox. Bi2Sr2CaCu2Ox films were successfully fabricated on nickel substrates using the metal alkoxide solution at the nominal composition of BiSrCaCu=2223. Bi2Sr2CaCu2Ox was precipitated on Ni substrates at firing temperature of 770 °C or above, and a sharp T
c was obtained at the firing temperature of 800 °C. 相似文献
106.
Protein Folding in the Presence of Water‐Soluble Cyclic Diselenides with Novel Oxidoreductase and Isomerase Activities 下载免费PDF全文
Dr. Kenta Arai Haruhito Ueno Yuki Asano Gaurango Chakrabarty Shingo Shimodaira Prof. Dr. Govindasamy Mugesh Prof. Dr. Michio Iwaoka 《Chembiochem : a European journal of chemical biology》2018,19(3):207-211
The protein disulfide isomerase (PDI) family, found in the endoplasmic reticulum (ER) of the eukaryotic cell, catalyzes the formation and cleavage of disulfide bonds and thereby helps in protein folding. A decrease in PDI activity under ER stress conditions leads to protein misfolding, which is responsible for the progression of various human diseases, such as Alzheimer's, Parkinson's, diabetes mellitus, and atherosclerosis. Here we report that water‐soluble cyclic diselenides mimic the multifunctional activity of the PDI family by facilitating oxidative folding, disulfide formation/reduction, and repair of the scrambled disulfide bonds in misfolded proteins. 相似文献
107.
Finite element analysis of fracture statistics of ceramics: Effects of grain size and pore size distributions 下载免费PDF全文
Shingo Ozaki Yuya Aoki Toshio Osada Kyohei Takeo Wataru Nakao 《Journal of the American Ceramic Society》2018,101(7):3191-3204
A novel numerical simulation method based on finite element analysis (FEA), which can evaluate the fracture probability caused by the characteristics of flaw distribution, is considered an effective tool to facilitate and increase the use of ceramics in components and members. In this study, we propose an FEA methodology to predict the scatter of ceramic strength. Specifically, the data on the microstructure distribution (i.e., relative density, size and aspect ratio of pore, and grain size) are taken as the input values and reflected onto the parameters of a continuum damage model via a fracture mechanical model based on the circumferential circular crack emanating from an oval spherical pore. In addition, we numerically create a Weibull distribution based on multiple FEA results of a three‐point bending test. Its validity is confirmed by a quantitative comparison with the actual test results. The results suggest that the proposed FEA methodology can be applied to the analysis of the fracture probability of ceramics. 相似文献
108.
Taisuke Tomonaga Hiroto Izumi Yukiko Yoshiura Toshihiko Myojo Takako Oyabu Byeong-Woo Lee Takami Okada Takashi Marui Ke-Yong Wang Masaru Kubo Manabu Shimada Shingo Noguchi Chinatsu Nishida Kazuhiro Yatera Yasuo Morimoto 《Particle and fibre toxicology》2018,15(1):41
Background
In order to examine whether myeloperoxidase (MPO) can be a useful marker for evaluating the pulmonary toxicity of nanomaterials, we analyzed MPO protein in bronchoalveolar lavage fluid (BALF) samples obtained from previous examinations of a rat model. In those examinations we performed intratracheal instillation exposures (dose: 0.2–1.0 mg) and inhalation exposures (exposure concentration: 0.32–10.4 mg/m3) using 9 and 4 nanomaterials with different toxicities, respectively. Based on those previous studies, we set Nickel oxide nanoparticles (NiO), cerium dioxide nanoparticles (CeO2), multi wall carbon nanotubes with short or long length (MWCNT (S) and MWCNT (L)), and single wall carbon nanotube (SWCNT) as chemicals with high toxicity; and titanium dioxide nanoparticles (TiO2 (P90) and TiO2 (Rutile)), zinc oxide nanoparticles (ZnO), and toner with external additives including nanoparticles as chemicals with low toxicity. We measured the concentration of MPO in BALF samples from rats from 3 days to 6 months following a single intratracheal instillation, and from 3 days to 3 months after the end of inhalation exposure.Results
Intratracheal instillation of high toxicity NiO, CeO2, MWCNT (S), MWCNT (L), and SWCNT persistently increased the concentration of MPO, and inhalation of NiO and CeO2 increased the MPO in BALF. By contrast, intratracheal instillation of low toxicity TiO2 (P90), TiO2 (Rutile), ZnO, and toner increased the concentration of MPO in BALF only transiently, and inhalation of TiO2 (Rutile) and ZnO induced almost no increase of the MPO. The concentration of MPO correlated with the number of total cells and neutrophils, the concentration of chemokines for neutrophils (cytokine-induced neutrophil chemoattractant (CINC)-1 and heme oxygenase (HO)-1), and the activity of released lactate dehydrogenase (LDH) in BALF. The results from the receiver operating characteristics (ROC) for the toxicity of chemicals by the concentration of MPO proteins in the intratracheal instillation and inhalation exposures showed that the largest areas under the curves (AUC) s in both examinations occurred at 1 month after exposure.Conclusion
These data suggest that MPO can be a useful biomarker for the ranking of the pulmonary toxicity of nanomaterials, especially at 1 month after exposure, in both intratracheal instillation and inhalation exposure.109.
Kei Takahashi Takehisa Sato Roh Yamamoto Hideaki Shishido Toshiyuki Isa Shingo Eguchi Hiroyuki Miyake Yoshiharu Hirakata Shunpei Yamazaki Rai Sato Hironori Matsumoto Naomi Yazaki 《Journal of the Society for Information Display》2015,23(12):600-606
A prototype 13.3‐inch 8k4k 664‐ppi high‐resolution foldable organic light emitting diode display is constructed. C‐axis aligned a‐b‐plane‐anchored crystal In–Ga–Zn oxide field effect transistors designed using a 1.5‐µm rule process are used in the backplane. Each pixel circuit has three transistors and one capacitor, and an external circuit is used to correct pixel current. 相似文献
110.
Fusaomi Nagata Kazuhiro Takeshita Shingo Yoshimoto Akira Yoshinaga Shingo Kurita Akimasa Otsuka Keigo Watanabe Maki K. Habib 《Artificial Life and Robotics》2016,21(3):332-337
In this paper, viewer and converter softwares are presented for smart machining process using an industrial robot. The viewers for NC, CLS, DXF and STL files illustrate their surface representation with normal direction vectors. For example, the DXF is a data format developed by Autodesk to realize data interoperability among different makers’ CAD systems. The STL means Stereolithography which is a file format proposed by 3D Systems and recently is supported by many design tools and CAD/CAM softwares. In addition, the converters for DXF and STL files generate the corresponding CLS files with normal direction vectors for machining. Further, the proposed preprocessor allows the developed machining robot to work based on information included in STL files. The convenience and user-friendliness of the proposed integrated system are confirmed through experiments of viewing, converting and machining. 相似文献