全文获取类型
收费全文 | 54篇 |
免费 | 7篇 |
国内免费 | 3篇 |
专业分类
电工技术 | 5篇 |
化学工业 | 9篇 |
金属工艺 | 4篇 |
机械仪表 | 2篇 |
建筑科学 | 1篇 |
轻工业 | 27篇 |
一般工业技术 | 6篇 |
冶金工业 | 2篇 |
原子能技术 | 1篇 |
自动化技术 | 7篇 |
出版年
2018年 | 1篇 |
2016年 | 3篇 |
2015年 | 1篇 |
2014年 | 3篇 |
2013年 | 9篇 |
2011年 | 3篇 |
2009年 | 1篇 |
2007年 | 1篇 |
2006年 | 2篇 |
2005年 | 1篇 |
2002年 | 2篇 |
2000年 | 1篇 |
1998年 | 1篇 |
1997年 | 7篇 |
1996年 | 2篇 |
1995年 | 2篇 |
1992年 | 1篇 |
1991年 | 1篇 |
1990年 | 2篇 |
1989年 | 3篇 |
1988年 | 2篇 |
1987年 | 2篇 |
1985年 | 2篇 |
1982年 | 1篇 |
1981年 | 2篇 |
1978年 | 1篇 |
1976年 | 1篇 |
1975年 | 2篇 |
1970年 | 3篇 |
1954年 | 1篇 |
排序方式: 共有64条查询结果,搜索用时 257 毫秒
1.
The tetragonal (t) to monoclinic (m) transformation behaviour and its relationship to microstructural evolution were investigated by means of dilatometry and transmission electron microscopy for ZrO2–9.7 mol% MgO during cyclic heating and cooling between room temperature and 1490 K. In the as-sintered specimens, fine oblate ellipsoidal t-phase precipitates, 20–50 nm in diameter and 100–200 nm long, were distributed in the cubic (c)-phase matrix. They were below a critical size for transformation and exhibited no transformation in the first three cycles. In the fourth and further cycles, transformation occurred in two distinct stages. A low-temperature stage appeared at 850–1000 K on heating and at 400–700 K on cooling, while a high-temperature stage appeared at 1350–1400 K on heating and at 1000–1200 K on cooling. With the increasing number of cycles, at first the size of low-temperature stages increased and then decreased above ten cycles accompanying the development of the high-temperature stage. During cyclic heating and cooling, coarsening of ellipsoidal precipitates and decomposition of c- and t-phases occurred. As a result of the decomposition, MgO particles and a new m-phase containing a very low concentration of MgO were produced. The coarsened ellipsoidal t-phase precipitates were responsible for the low-temperature stage. The new m- or t-phase containing very low MgO produced by the decomposition was responsible for the high-temperature stage. 相似文献
2.
HIRAMITSU SUZUKI SHUN WADA SEIICHI HAYAKAWA SINPATIRO TAMURA 《Journal of food science》1985,50(2):358-360
To prevent loss of w3 polyunsaturated fatty acids over long-term preservation, the effects of temperature and oxygen absorber on the fatty acids of sardine oil stored in air-tight film were studied. The fatty acids of sardine oil and lipids in the diet of experimental animals rapidly decreased over 1 month at 22°C. The amounts in the diet decreased slowly at 2°C; however, no alterations in the oil samples were observed for 6 months. Also, the amounts did not change at -30°C. Significant changes in samples treated with oxygen absorber were not observed under all temperatures during 6 months storage (P > 0.05). These results indicate that treatment with an oxygen absorber and/or freezing can prevent ω3 polyunsaturated fatty acids of fish oil from decreasing during storage. 相似文献
3.
MASATO MACHIDA KOICHI EGUCHI HIROMICHI ARAI 《Journal of the American Ceramic Society》1988,71(12):1142-1147
The formation process of barium hexaaluminate (BaO 6Al2 O3 ) from BaCO3 /γ-Al2 O3 powders or hydrolyzed alkoxides was studied by analytical electron microscopy. Barium hexaaluminate is produced by a two-step solid-state reaction from BaCO3 and Al2 O3 via formation of BaO·Al2 O3 . Marked grain growth and inclusion of nonequilibrium phase were inevitable in this powder mixture process. However, in an alkoxide-derived precursor, homogeneous mixing of components is attained and hence the formation of BaO·6Al2 O3 proceeds readily. Powders obtained by this latter route consisted of fine planar particles with a uniform size and retained a large surface area (20.2 m2 /g) even after heating at 1300°C. Electron diffraction results implied that suppression of crystal growth along the c axis is the reason for the large surface area of BaO·6Al2 O3 . 相似文献
4.
SEIICHI NAKAMORI 《International journal of systems science》2013,44(12):2573-2584
The optimal fixed-point smoother is designed based on an innovations theory for the white gaussian plus coloured observation noise in linear continuous systems. The signals to be estimated are non-stationary or stationary stochastic processes. The proposed fixed-point smoothing algorithm calculates estimates sequentially by using the observed value, the autocovariance function of the signal plus the coloured observation noise process and the cross-covariance function of the signal with the observed value. 相似文献
5.
Takashi MINAMI Shohei ARAI Naoki KENMOCHI Hiroaki YASHIRO Chihiro TAKAHASHI Shinji KOBAYASHI Tohru MIZUUCHI Shinsuke OHSHIMA Satoshi YAMAMOTO Hiroyuki OKADA Kazunobu NAGASAKI Yuji NAKAMURA Kiyoshi HANATANI Shigeru KONOSHIMA Fumimichi SANO 《等离子体科学和技术》2013,(3):240-243
A new high repetition rate Nd:YAG Thomson scattering system is developed for the Heliotron J helical device.A main purpose of installing the new system is the temporal evolution measurement of a plasma profile for improved confinement physics such as the edge transport barrier (H-mode) or the internal transport barrier of the helical plasma.The system has 25 spatial points with ~10mm resolution.Two high repetition Nd:YAG lasers (>550mJ@ 50Hz) realize the measurement of the time evolution of the plasma profile with ~10ms time intervals.Scattered light is collected by a large concave mirror (D=800 mm,f/2.25) with a solid angle of ~100 mstr and transferred to interference filter polychromators by optical fiber bundles in a staircase form.The signal is amplified by newly designed fast preamplifiers with DC and AC output,which reduces the low frequency background noise.The signals are digitized with a multi-event QDC,fast gated integrators.The data acquisition is performed by a VME-based system operated by the CINOS. 相似文献
6.
Acid Urease: Reduction of Ethyl Carbamate Formation in Sherry under Simulated Baking Conditions 总被引:1,自引:0,他引:1
Acid urease derived from Lactobacillus fermentum was applied to reduce ethyl cthe target level (90 μg/L). However, complete prearbamate (EC) formation in California sherry production. Commercial sherry and sherry base were treated with urease under different conditions. Amounts of urea were determined and EC amounts were monitored by gas chromatography. Urea removal by acid urease reduced EC formation during the baking process and effectively maintained EC concentrations below vention of EC was not achieved because of precursors other than urea. 相似文献
7.
SOICHI ARAI MASATOSHI NOGUCHI SHUKUKO KUROSAWA HIROMICHI KATO MASAO FUJIMAKI 《Journal of food science》1970,35(4):392-395
SUMMARY— A proteolyzate obtained by treating an isolated soybean protein preparation with Molsin, a crude preparation of aspergillopeptidase A (APase A), was less bitter and contained larger amounts of free amino acids, especially hydrophobic amino acids. A proteolyzate obtained by treating this protein preparation with crystallized APase A was much more bitter and contained smailer amounts of free amino acids, mainly consisting of hydrophilic amino acids. The latter was richer in peptides than the former, bearing hydrophobic amino acid residues near the C-termini. Difference in N-terminal amino acid composition apparently has not been found between the 2 proteolyzates. These results indicate that Molsin per se contains a certain carboxypeptidase which decomposes the C-terminal structures and, consequently, lessens the bitterness (debittering effect). This carboxypeptidase was found to be identical with aspergillus acid carboxypeptidase (AACPase). Abase A, as well as MO/sin, was effective in removing odor ants, i.e., n-hexanal, n-hexanol and n-heptanol, from the isolated soybean protein preparation Ideodorization effect). AACPase seemed to have no deodorization effect. A method was suggested to prepare a deodorized and debittered proteolyzate by a combination use of APase A and AACPase. 相似文献
8.
研究了一种SiCp及Al2O3w增强铸态混杂金属基复合材料(MMC)的疲劳裂纹扩展(FCG)机理,同时对比研究了Al2O3w增强铸态金属基复合材料和铸态铝合金的疲劳裂纹扩展机理。在研究近临界和裂纹稳定扩展区域的疲劳裂纹扩展(FCG)机理时,发现混杂MMC的临界应力强度因子?Kth值高于其他两种材料的?Kth值,说明应力强度因子?K值较低时混杂MMC可以更好地抵抗裂纹扩展。随着?K值的降低,两种MMC在近临界区域显示出相似的FCG机理,即主要由增强相–基体界面的剥离控制,随后由铝基体中空隙的形核与合并控制;在裂纹稳定或中等扩展区域,?K值较高时FCG除了受界面上周期性裂纹扩展引起的增强相–基体界面剥离的影响之外,还显著受到铝基体中疲劳条带的影响。此外,在高?K值下,因为局部失稳断裂机制,可见铝基体中空隙的形核与合并以及SiCp和Al2O3w中的穿晶断裂。对于铸态铝合金,在低?K值下,FCG主要受空隙的形核与合并所控制;在高?K值下,FCG主要受铝晶粒的疲劳条带控制,随后受Si团簇中空隙的形核与合并控制。 相似文献
9.
Cystatins are protein inhibitors of cysteine proteinases. Oryzacystatin I (OC-I) has been cloned and is apparently the first well-defined cystatin of plant origin (phytocystatin). Besides OC-I, various other phytocystatins occur in rice, corn, wheat and soybean. Phytocystatins have endogenous target enzymes whose expression is induced by gibberellin, and also exogenous target enzymes from viruses and insects. It is thus likely that phytocystatins are involved in the regulation of intracellular protein catabolism as well as in the defense from infection. Better understanding of this phenomenon and cloning of appropriate genes will facilitate the creation of transgenic crops with enhanced resistance to viruses and insects. 相似文献
10.
KEN'ICHI TAKANO KUNIHIDE SASOU SEIICHI YOSHIMURA 《International journal of human-computer studies》1997,47(6):767-789
Accidents occurring in nuclear power plants cannot be depended upon to train experts of nuclear operators. Generally, this expertise is developed through the simulator training. In this training course, only limited varieties of malfunctions can be presented. Thus, it would be impossible for operators to cope with any other possible anomalies of diverse varieties. Operators have to reorganize knowledge and experiences obtained in the training. Of course, prescribed procedures are far from covering them. This paper presents the structure and contents of a “operator's mental model” and it can deal with flexible operations under any situation. Based on the record of the simulator experiments, in-depth analyses were conducted by interviewing with experienced operators in order to model operators' thinking patterns and also to arrive at the aims behind their actions and utterances. Summarizing the findings obtained, fundamental functions of the mental model in coping with anomalies resulted in the following: (1) suggesting suitable preventive measures by envisioning the ongoing (future) scenario of plant dynamics; (2) identifying causes by investigating symptoms and implying causal remedies to eliminate them or to avoid influences from them and (3) adopting immediate responses simply formulated by “if alarm A then action B”. These functions, as well as the mental model itself, can be made available by getting information on plant status and operator's structured knowledge together. The substances and structures of the mental models could be proposed, including implications of how to create it for a specific event, and finally they were synthesized into a more generalized format. 相似文献