全文获取类型
收费全文 | 803篇 |
免费 | 9篇 |
国内免费 | 1篇 |
专业分类
电工技术 | 29篇 |
综合类 | 1篇 |
化学工业 | 227篇 |
金属工艺 | 18篇 |
机械仪表 | 11篇 |
建筑科学 | 23篇 |
矿业工程 | 1篇 |
能源动力 | 25篇 |
轻工业 | 125篇 |
水利工程 | 2篇 |
无线电 | 43篇 |
一般工业技术 | 150篇 |
冶金工业 | 122篇 |
原子能技术 | 7篇 |
自动化技术 | 29篇 |
出版年
2024年 | 3篇 |
2023年 | 3篇 |
2022年 | 9篇 |
2021年 | 28篇 |
2020年 | 6篇 |
2019年 | 18篇 |
2018年 | 9篇 |
2017年 | 12篇 |
2016年 | 16篇 |
2015年 | 7篇 |
2014年 | 24篇 |
2013年 | 39篇 |
2012年 | 38篇 |
2011年 | 52篇 |
2010年 | 35篇 |
2009年 | 33篇 |
2008年 | 32篇 |
2007年 | 29篇 |
2006年 | 26篇 |
2005年 | 20篇 |
2004年 | 26篇 |
2003年 | 51篇 |
2002年 | 21篇 |
2001年 | 14篇 |
2000年 | 17篇 |
1999年 | 15篇 |
1998年 | 50篇 |
1997年 | 40篇 |
1996年 | 24篇 |
1995年 | 14篇 |
1994年 | 11篇 |
1993年 | 10篇 |
1992年 | 4篇 |
1991年 | 4篇 |
1990年 | 11篇 |
1989年 | 7篇 |
1988年 | 9篇 |
1987年 | 6篇 |
1986年 | 8篇 |
1985年 | 5篇 |
1984年 | 3篇 |
1983年 | 4篇 |
1982年 | 4篇 |
1981年 | 2篇 |
1980年 | 2篇 |
1978年 | 4篇 |
1976年 | 4篇 |
1973年 | 1篇 |
1972年 | 1篇 |
1967年 | 1篇 |
排序方式: 共有813条查询结果,搜索用时 15 毫秒
781.
Three specimens of localized amyloidosis of the seminal vesicle surgically removed for prostatic cancer were immunohistochemically analyzed to clarify the nature of the permanganate-sensitive congophilic subepithelial deposition. A variety of known amyloidogenic substances and secretory products in the seminal fluid were screened using the indirect immunoperoxidase method. In addition to reactivities with antibodies to amyloid P component and human seminal plasma, the amyloid material was immunoreactive for lactoferrin using a rabbit antiserum and two of three mouse monoclonal antibodies. All the antibodies labeled some of the normal seminal vesicle epithelial cells for this ironbinding, bacteriostatic glycoprotein. In the prostate without accompanying amyloid deposition, a considerable proportion of the glandular epithelium and secretory material were positive for lactoferrin. Pre-embedding immunoelectron microscopy showed lactoferrin immunoreactivity on the amyloid fibrils. Focal staining of the amyloid for gross cystic disease fluid protein-15 was also observed in two lesions. These findings strongly suggest that lactoferrin is the major constituent in localized senile amyloidosis of the seminal vesicle. 相似文献
782.
A Tsutsumi E Matsuura K Ichikawa A Fujisaku M Mukai S Kobayashi T Koike 《Canadian Metallurgical Quarterly》1996,39(9):1466-1474
OBJECTIVE: To investigate whether anticardiolipin antibodies (aCL) in patients with systemic lupus erythematosus (SLE) bind to beta 2-glycoprotein I (beta 2GPI), and to search for a relationship between the presence of IgG and/or IgM anti-beta 2GPI antibody and clinical manifestations in SLE patients. METHODS: IgG and IgM anti-beta 2GPI in 308 Japanese SLE patients were measured using phospholipid-independent enzyme immunoassays. Relationships to clinical histories and to various laboratory data were examined. RESULTS: The values of anti-beta 2GPI and aCL, as measured by conventional enzyme immunoassay, showed a strong correlation, but the anti-beta 2GPI assay was more useful in distinguishing beta 2GPI-dependent aCL from beta 2GPI-independent aCL. The presence of IgG anti-beta 2GPI was associated with an increased frequency of a history of thrombosis. Comparisons of various laboratory data suggested that the titer of anti-beta 2GPI may fluctuate with disease activity. CONCLUSION: The results suggest that pathogenic aCL is directed against structurally altered beta 2GPI and that enzyme immunoassay for anti-beta 2GPI may prove useful in evaluating the risk of thrombosis and monitoring the clinical course in patients with SLE. 相似文献
783.
784.
Lanthanum hexaboride was synthesized by reacting a powdered mixture of hexagonal boron nitride and lanthanum-citrate-hydrate carbonized substance which had been prepared by heating lanthanum-citrate-hydrate at 1000° C in a nitrogen atmosphere. The optimum conditions for the synthesis were a ratio of boron to lanthanum in the starting mixture between 5.0 and 6.0 with heating in the temperature range 1480 and 1600° C in an evacuated atmosphere. 相似文献
785.
Sawada Anju Ishiguro Akiko Inada Yoshihiko Suzuki Michiro Sato Noriaki Komatsubara Takemi 《Journal of Low Temperature Physics》1995,101(3-4):645-650
The ac magnetic susceptibility of UPd2Al3 in the superconducting state has been measured to test of the existence of the Fulde, Ferrell, Larkin and Ovchinnikov (FFLO) state. A dip in the susceptibility has been observed in the vicinity of the upper critical field and the temperature range from zero to Tc. This dip is very sensitive to the amplitude of the ac magnetic field. The anomaly is explained by the increase of the flux pinning effect. Recent theories suggest that the pinning force becomes stronger in the FFLO state, and the existence of the nonuniform state due to the order parameter mixing in a d-wave superconductor is possible near Tc. 相似文献
786.
Conventional fiber reinforced plastics (FRPs) have some problems in the case of disposal. Their combustion disposal discharges the carbon dioxide in the air because resins of FRPs are made of fossil fuel. In the case of disposal into the ground, these FRPs remain semi-permanently without decomposing. Therefore, green composites are now developed and are studied as one of less the environmental burden materials. In this study, two kinds of continuous green composite sheets, which were composed of Kenaf fibers or Linen fibers as reinforcement and biodegradable poly butylene succinate (PBS) resin as a matrix, were fabricated with a pultrusion molding. Since the PBS resin is a thermoplastic resin, the PBS/KENAF or PBS/LINEN composite sheets can be treated as intermediate materials such as Carbon Fiber Reinforced Plastic prepregs. In order to apply the PBS/KENAF or PBS/LINEN composite sheets to structural components, quasi-isotropic plates and cylindrical shells were fabricated and evaluated. 相似文献
787.
788.
Akiko Isa Jun Minamino Yoichi Kojima Shigehiko Suzuki Hirokazu Ito Rie Makise 《木材化学与工艺学杂志》2016,36(2):105-113
In this study, we evaluated the influence of wood flour (particle size: <90 μm) on the physical properties of wood flour/polypropylene (PP) composites. Wood flour was obtained by dry ball-milling of forest-thinning material at a rotary speed of 250 rpm for 1, 2, 4, and 8 h. The milled wood flour was filtered using a 90 μm sieve. The water content of the wood flour was adjusted to 5, 10, or 20 wt%. Composite properties, including mechanical properties, water absorption, and thermal expansion, were evaluated at wood flour loadings of 40 wt%. When wood flour with 5 wt% water content was milled for 2 and 4 h, the resulting wood flour was granular rather than fibrous; flocculation of the fine particles was observed for milling times exceeding 4 h. This morphological change in the wood flour reduced its influence on the physical properties of the composites, although some positive influences were observed on the molding properties of the composite, such as an increase in compound fluidity. Milled wood flour with 10 wt% or 20 wt% water content was fibrous. Scanning electron microscopy observation of milled wood flour with 10 wt% water content revealed partial surface fibrillation at widths of tens to hundreds of nanometers. The addition of wood flour with nanoscale surface fibrils to PP composites positively influenced the properties of the composite, resulting in a decrease in the linear coefficient of thermal expansion in the flow direction. 相似文献
789.
790.
Okamoto-Kainuma A Yan W Fukaya M Tukamoto Y Ishikawa M Koizumi Y 《Journal of Bioscience and Bioengineering》2004,97(5):339-342
The dnaKJ operon of Acetobacter aceti was cloned and sequenced. The profile of the gene configuration was similar to that of other alpha-proteobacteria. In the DnaK and DnaJ proteins of A. aceti, the characteristic domains/motifs reported in other organisms were well conserved. This operon was transcribed in response to a temperature shift and exposure to ethanol/acetic acid. The overexpression of this operon in A. aceti resulted in improved growth compared to the control strain at high temperature or in the presence of ethanol, suggesting a correlation to resistance against stressors present during fermentation, although the overexpression did not increase the resistance to acetic acid. 相似文献