全文获取类型
收费全文 | 110篇 |
免费 | 1篇 |
专业分类
电工技术 | 11篇 |
化学工业 | 17篇 |
金属工艺 | 2篇 |
机械仪表 | 3篇 |
建筑科学 | 2篇 |
能源动力 | 13篇 |
轻工业 | 6篇 |
水利工程 | 1篇 |
石油天然气 | 1篇 |
无线电 | 9篇 |
一般工业技术 | 17篇 |
冶金工业 | 24篇 |
原子能技术 | 2篇 |
自动化技术 | 3篇 |
出版年
2020年 | 5篇 |
2018年 | 1篇 |
2017年 | 2篇 |
2014年 | 2篇 |
2013年 | 6篇 |
2012年 | 5篇 |
2011年 | 6篇 |
2010年 | 9篇 |
2009年 | 2篇 |
2008年 | 5篇 |
2007年 | 10篇 |
2006年 | 4篇 |
2005年 | 5篇 |
2004年 | 1篇 |
2002年 | 3篇 |
2001年 | 1篇 |
2000年 | 1篇 |
1999年 | 2篇 |
1998年 | 10篇 |
1997年 | 10篇 |
1996年 | 5篇 |
1995年 | 1篇 |
1994年 | 1篇 |
1993年 | 1篇 |
1990年 | 1篇 |
1989年 | 1篇 |
1988年 | 1篇 |
1987年 | 1篇 |
1986年 | 3篇 |
1983年 | 2篇 |
1982年 | 2篇 |
1976年 | 1篇 |
1972年 | 1篇 |
排序方式: 共有111条查询结果,搜索用时 15 毫秒
31.
Nagata S Tsuneta S Sakao T Yoshida T Hara H Kano R Ishiyama W Murakami K Ohtan M 《Applied optics》1997,36(13):2830-2838
Multilayer mirrors with a system wavelength resolution (lambda/Dlambda) as high as 30-50 are required for the diagnostics of cosmic plasmas with temperatures of 1-20 MK. Such a high wavelength resolution can be realized by increasing the number of layer pairs contributing to the reflectance, by selecting less-absorbing materials for both the reflector and the spacer, and by decreasing the thickness of the reflector. We have fabricated a multilayer mirror tuned to 284 A with a silicon carbide reflector (20% thickness of the layer period) and an aluminum spacer and achieved lambda/Dlambda ~26.8 with a peak reflectivity of ~13.0%. This wavelength resolution is close to the value obtained with a numerical simulation and is considerably higher than the value obtained with the conventional Mo/Si multilayer. 相似文献
32.
T Ishiyama K Watanabe K Fukuchi K Yajima M Koike S Tomoyasu N Tsuruoka 《Canadian Metallurgical Quarterly》1993,37(2-3):139-144
CD5 antigen is present on all normal alpha beta T cells and some B cells. Human NK cells do not usually express CD5 antigen, but we found a subset of CD5LOW+ (low density of CD5) NK cells in some patients with pulmonary tuberculosis. Unlike CD5-NK cells, most CD5LOW+NK cells had HLA-DR. We observed few CD5LOW+NK cells in the normal controls and some in the large granular lymphocyte (LGL) population purified by Percoll density centrifugation. Sorted CD5LOW+NK populations were LGL. The CD5LOW+NK cells had high lytic activity on K562 cells in a 4-h 51chromium release assay. Our results indicate that there is a previously unidentified subset of NK cells. 相似文献
33.
Ichiro Sasagawa Mikio Ishiyama Hiroyuki Yokosuka Masato Mikami 《Frontiers of Materials Science in China》2008,2(2):134-142
The fine structure of collar enamel and the cells constituting the enamel organ during amelogenesis in Lepisosteus oculatus was observed by light, scanning electron and transmission electron microscopy. In the enamel, slender crystals were arranged
perpendicular to the surface and the stripes that were parallel to the surface were observed, suggesting that the enamel in
Lepisosteus shares common morphological features with that in sarcopterygian fish and amphibians. Ameloblasts containing developed Golgi
apparatus, rough endoplasmic reticulum (rER) and secretory granules were found in the secretory stage. In the maturation stage,
a ruffled border was not seen at the distal end of the ameloblasts, while many mitochondria and lysosome-like granules were
obvious in the distal cytoplasm. The enamel organ consisted of the outer dental epithelial cells, stratum reticulum cells
and ameloblasts, but there was no stratum intermedium. It is likely that the ameloblasts have less absorptive function in
comparison with the inner dental epithelial cells facing cap enameloid. 相似文献
34.
Eades LJ Farmer JG MacKenzie AB Kirika A Bailey-Watts AE 《The Science of the total environment》2002,292(1-2):55-67
Sediment cores from three Scottish freshwater lakes, Loch Ness in the remote north and Loch Lomond and the Lake of Menteith, much closer to the heavily populated and industrialised central belt were analysed for 210Pb, 137Cs, Pb and stable Pb isotopic composition (206Pb/207Pb). The radionuclide data were used to establish chronologies for the Loch Ness and Loch Lomond cores, but a chronology could not be developed for the Lake of Menteith core, in which the surface sediment had been subject to intense mixing. Although Pb concentrations generally started increasing during the mid-17th Century, a small peak occurred for Loch Ness in the early 16th Century, perhaps attributable to the influence of medieval mining and smelting in mainland Europe. Temporal trends in the pattern of Pb accumulation were similar for Loch Ness and both sites in Loch Lomond, with 40-50% of the anthropogenic Pb deposited prior to the 20th Century. Fluxes of anthropogenic Pb to the lake sediments peaked during the 1950s at all locations where chronologies could be established. The 5-fold increase in anthropogenic Pb inventory for the southern basin of Loch Lomond relative to Loch Ness reflected geographical proximity to the main polluting sources. The 206Pb/207Pb data for anthropogenic Pb in the sediments from Loch Ness and Loch Lomond exhibited largely similar trends related to five different time periods. Pre-1820, the 206Pb/207Pb ratio was close to that for coal (1.181). From 1820 to 1900, a fairly constant 206Pb/207Pb ratio of approximately 1.17 probably resulted from a combination of emissions from the smelting of indigenous Pb ore (1.170) and coal burning (1.181) in Scotland, and industrial activity to the south in England, where Australian Pb of characteristically low 206Pb/207Pb ratio (1.04) was already in use. From 1901 to 1930, the 206Pb/207Pb ratio declined by <0.01, due to the increasing influence of Australian Pb. From 1931 to 1975/1985, the 206Pb/207Pb ratio of anthropogenic Pb declined by a further 0.03 to 0.04, to minimum values from approximately 1975 to 1985, primarily a consequence of car-exhaust emissions of Pb arising from the introduction of alkyl Pb petrol additives (206Pb/207Pb approximately 1.06-1.09). From 1975/1985 to the mid-1990s, the 206Pb/207Pb ratio of anthropogenic Pb increased by up to 0.015, a consequence of a reduction in car-exhaust emissions of Pb, resulting from reductions in the maximum permitted concentration of Pb in petrol, and the introduction and increasing uptake of unleaded petrol. Source apportionment calculations, on the basis of 206Pb/207Pb values in surface sediment, suggested that the contribution of Pb emissions from the use of leaded petrol was 27-40% of the atmospheric burden by the mid-1990s, in line with estimates from rainwater 206Pb/207Pb data. 相似文献
35.
AbstractParallel branches are commonly observed in industrial heat exchanger networks (HENs). Despite the important relationship between flow distribution and network efficiency, not all parallel branches comprise of flow controllers or not least, flow measurements. When the network is subject to fouling, uncontrolled flow branches can introduce undesired phenomenon such as thermo-hydraulic channeling (THC) [presented at the 2007 HEFC conference; Ishiyama et al., Effect of fouling on heat transfer, pressure drop and throughput in refinery preheat trains]. Recent analysis of crude preheat train heat exchangers has shown the need to use THC models, in particular, for situations where there is insufficient flow measurement data, especially in nonsymmetric branches. This paper revisits the THC model and highlight practical importance of the THC phenomenon through analysis of plant data. The hydraulic aspect of the analysis is strongly linked to the knowledge of deposit thermal conductivity. A case study of a section of a crude refinery HEN is used to illustrate the use of thermo-hydraulic models in data reconciliation to understand flow imbalances caused due to differences in operating conditions and fouling of heat exchangers in each branch of a parallel network. 相似文献
36.
Two patients had fatal fat pulmonary embolism during bipolar hip endoprosthesis. Two women, 71-year-old and 76-year-old, with femoral neck fracture underwent bipolar hip endoprosthesis under combined lumbar epidural/general anesthesia. Soon after the placement of bone cement and a femoral stem with a bipolar endoprosthesis in the femoral shaft, the patients developed circulatory collapse. Immediate cardiopulmonary resuscitation did not restore adequate circulation and the patients died 3.5 hours and 1 hour thereafter, respectively. Pathological examination revealed the presence of fat particles within the entire pulmonary arteries, arterioles and capillaries. Main cause of the present pulmonary fat embolism may be an increase in the intramedullary pressure during cement pressurization and femoral stem placement. Anesthetists have to be aware of occurrence of this serious syndrome during bipolar hip endoprosthesis. For earlier detection of this serious complication we recommend to monitor central venous pressure and pulmonary artery pressure in patients undergoing bipolar hip endoprosthesis. 相似文献
37.
Chemical effects of DCCA to the sol-gel reaction process 总被引:7,自引:0,他引:7
The effects of drying control chemical additives (DCCA) on the growth of silica particles, gelation time and physical properties of the dry gel were examined in a two-step silica sol-gel process.N,N-dimethylformamide,N,N-dimethylacetamide and ethylene glycol (EG) were applied as DCCAs. The shapes of growing silica particles were distorted spheres on addition of DCCA. EG accelerated the gelation process. Despite the use of DCCA, crack-free, dry gels were obtained only under limited conditions. 相似文献
38.
In the present study a Pd-Ni-P film has been fabricated by electroless alloy plating. The fabricated Pd-Ni-P film was found to be a metallic glass on the basis of two features, namely, an amorphous structure and a glass transition followed by crystallization during heating. The thermal stability of the supercooled liquid region, however, was lower than that of bulk Pd-Ni-P metallic glass. And unlike the conventional metallic glasses, the fabricated Pd-Ni-P film did not have a uniform microstructure. The non-uniform microstructure of this film resulted from the inhomogeneous distribution of the free volume accompanying the electroless alloy plating reaction. 相似文献
39.
Interlayer Pd for the Li/Pd/Cu neutron target for BNCT (boron neutron capture therapy) was characterized after 0.1-5 keV H2^+ irradiation by XAFS (X-ray absorption fine structure) technique, and following conclusions were derived: (1) from the XAFS observation of white line of Pd, remarkable Pd L3 edge jump was found in 1.1-3 times higher than before irradiation in low irradiation fluence; (2) this fact indicates increase of hole density in Pd 4d-band, whereas, no change was observed for XASF spectra of Ag sample under the same irradiation conditions; (3) remarkable Pd L3 edge shift of 0.12-0.66 eV was also found with increase of H2+ irradiation energy in low fluence, and drastically decreased after peak in high irradiation energy and fluence; (4) implanted protons deposited in Pd as negative under the balance of electron population enhanced by proton irradiation and charge transfer. 相似文献
40.
Describes Morita therapy, a Japanese cognitive–behavioral therapy that aims toward clients' acceptance of the self-actualizing and existential meaning of anxiety (i.e., the fear of death and failure), instead of trying to resist or control anxiety symptoms. The positive reinterpretation technique attempts to mobilize clients' energy from egocentric self-preocccupations to productive and constructive action-taking. A case illustration is presented of a 35-yr-old female death-anxious client with paroxysmal anxiety reactions who was successfully treated in a single Morita session; successful maintenance continued at 40-mo follow-up. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献