全文获取类型
收费全文 | 541篇 |
免费 | 23篇 |
国内免费 | 1篇 |
专业分类
电工技术 | 49篇 |
综合类 | 2篇 |
化学工业 | 150篇 |
金属工艺 | 6篇 |
机械仪表 | 9篇 |
建筑科学 | 6篇 |
能源动力 | 24篇 |
轻工业 | 54篇 |
石油天然气 | 2篇 |
无线电 | 47篇 |
一般工业技术 | 94篇 |
冶金工业 | 55篇 |
原子能技术 | 5篇 |
自动化技术 | 62篇 |
出版年
2022年 | 5篇 |
2021年 | 12篇 |
2020年 | 2篇 |
2019年 | 6篇 |
2018年 | 7篇 |
2017年 | 8篇 |
2016年 | 8篇 |
2015年 | 10篇 |
2014年 | 10篇 |
2013年 | 39篇 |
2012年 | 20篇 |
2011年 | 28篇 |
2010年 | 16篇 |
2009年 | 10篇 |
2008年 | 14篇 |
2007年 | 17篇 |
2006年 | 14篇 |
2005年 | 18篇 |
2004年 | 18篇 |
2003年 | 20篇 |
2002年 | 19篇 |
2001年 | 7篇 |
2000年 | 9篇 |
1999年 | 13篇 |
1998年 | 29篇 |
1997年 | 22篇 |
1996年 | 17篇 |
1995年 | 14篇 |
1994年 | 13篇 |
1993年 | 8篇 |
1992年 | 7篇 |
1991年 | 10篇 |
1990年 | 8篇 |
1989年 | 6篇 |
1988年 | 9篇 |
1987年 | 6篇 |
1986年 | 9篇 |
1985年 | 8篇 |
1984年 | 14篇 |
1983年 | 5篇 |
1982年 | 7篇 |
1981年 | 8篇 |
1980年 | 5篇 |
1979年 | 13篇 |
1978年 | 6篇 |
1977年 | 6篇 |
1974年 | 1篇 |
1973年 | 1篇 |
1970年 | 1篇 |
1960年 | 1篇 |
排序方式: 共有565条查询结果,搜索用时 18 毫秒
41.
Kazuhiro Ohyama Teruo Hamaoka Greg Asher Mark Sumner 《Electrical Engineering in Japan》2009,166(1):67-81
This paper proposes a method for the design of the adaptive rotor flux observer gain to improve stability at low speed and in regenerating mode. The method is based on stability analysis, which utilizes a linearized model considering all systems, including each control loop. Therefore, the proposed method considers the effects of motor constants and control circuit constants. The stability analysis using the transfer function for the rotor speed considers the arrangement of poles and zeros and the steady‐state error. The rotor flux observer gain which improves the stability for each operating condition is ascertained. This paper also proposes a real‐time tuning method for the observer gain. The validity of the proposed method was confirmed by simulation using Matlab Simulink and by experiment. © 2008 Wiley Periodicals, Inc. Electr Eng Jpn, 166(1): 67–81, 2009; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20715 相似文献
42.
Disposable Australian iron-slurry (AL) and NiO-MoO3-Al2O3 (NiMo) catalysts were used in hydrocracking experiments to convert Marlim vacuum residue (ML-VR) in a slurry-bed continuous flow reactor at temperatures of 440-460 °C, under a hydrogen pressure of 14.7 MPa and an LHSV of 0.5. The degree of conversion ranged from 54 to 83%, depending on the reaction temperature and catalyst used, with AL giving more complete conversion than NiMo. AL also proved more active in the removal of nickel. Hydrogen consumption was linearly correlated with conversion regardless of the catalyst used. 相似文献
43.
An experimental evaluation of spatial distribution for deeply penetrating protons in carbon material
Mitsuo Tosaki Daisuke Ohsawa Yasuhito Isozumi 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2005,230(1-4):59-62
The peak profile of the 4.8-MeV resonance by the 12C(p,p)12C reaction in backscattering geometry has been analyzed to examine two kinds of stragglings of proton, i.e. the depth straggling in the incoming path and the energy loss straggling in the outgoing path. The analysis, which is combined with existing theoretical treatments for the stopping process and the energy loss straggling, has made it possible to deduce the penetration depth and its spread at the resonance position in carbon materials. The present method, as a new tool for direct inspection of ion beams inside target material, is explained in detail. 相似文献
44.
Ray Nakashima Shuanghui Hao Hideki Honda Ryuichi Oguro Hidekazu Miyakawa Teruo Tsuji 《Electrical Engineering in Japan》2004,147(4):68-76
In this paper, position control of a linear slider with twin linear drives is considered. Recently, for high‐speed response, several linear motors have been used for linear slider systems. In such a linear slider, if the linear drives are controlled individually, their position responses may undergo vibrational disturbance by interaction with the output of the motors. To control this vibration, this paper presents a dynamic model of a linear slider system which consists of two motion systems decoupled by coordinate transformation, and proposes a feedback controller which is designed for these two decoupled systems. The effectiveness of the proposed method is confirmed by experiments. © 2004 Wiley Periodicals, Inc. Electr Eng Jpn, 147(4): 68–76, 2004; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10291 相似文献
45.
对影响超临界CO2流体处理苎麻纤维的因素,如温度、压力、时间以及助溶剂进行正交试验,对处理后的苎麻纤维的含杂情况、微结构、机械物理性能和热稳定性等性质作了测试分析。结果表明,超临界CO2流体处理苎麻织物的最佳工艺条件为:工作温度120℃、压力25MPa、时间40min、助溶剂0.1%。该处理可改善苎麻纤维的性能,提高其膨胀性,有利于后续加工,并为其进一步改性打下基础。 相似文献
46.
Minamida K Sujaya IN Tamura A Shigematsu N Sone T Yokota A Asano K Benno Y Tomita F 《Journal of Bioscience and Bioengineering》2004,98(4):244-250
Di-D-fructofuranose-1,2':2,3'-dianhydride (DFA III) was shown to enhance Ca absorption in rat and human intestine. The effects of DFA III administration (9 g per day for 4 weeks that corresponded to 3-fold the optimal dosage of DFA III) on human intestinal microbiota were studied using denaturing gradient gel electrophoresis (DGGE). The major groups of human intestinal microbiota reported previously: the Bacteroides, the Clostridium coccoides group (Clostridium cluster XIVa), the Clostridium leptum group (Clostridium cluster IV), and the Bifidobacterium group were detected. The similarity of 30 DGGE profiles based on the V3 region (before and after administration to the 15 subjects) of the 16S rDNA were calculated using Pearson's correlation based on numbers, positions and intensity of bands, and then a dendrogram of DGGE profiles was constructed by the unweighted pair group method using arithmetic average (UPGMA) clustering method. By these analyses, no difference in DGGE profiles after DFA III administration was observed in healthy subjects, while two subjects with chronic constipation showed different profiles, namely on numbers, positions and the intensity of some bands. Their stools were softer and stool frequencies increased and they obtained relief from constipation. 相似文献
47.
Effects of sea surface temperature accuracy on offshore wind resource assessment using a mesoscale model
下载免费PDF全文
![点击此处可从《风能》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Susumu Shimada Teruo Ohsawa Tetsuya Kogaki Gerald Steinfeld Detlev Heinemann 《风能》2015,18(10):1839-1854
Offshore wind simulations were performed with the Weather Research and Forecasting (WRF) model driven by three different sea surface temperature (SST) datasets for Japanese coastal waters to investigate the effect of the SST accuracies on offshore wind simulations. First, the National Centers for Environmental Prediction Final analysis (FNL) (1° × 1° grid resolution) and the Operational Sea Surface Temperature and Sea Ice Analysis (OSTIA) (0.05° × 0.05° grid resolution) datasets were compared with in situ measurements. The results show a decrease in accuracy of these datasets toward the coast from the open ocean. Aiming at an improved accuracy of SST data, we developed a new high‐resolution SST dataset (0.02° × 0.02° grid resolution). The new dataset referred to as MOSST is based on the Moderate Resolution Imaging Spectroradiometer (MODIS) product, provided by the Japan Aerospace Exploration Agency (JAXA). MOSST was confirmed to be more accurate than FNL and OSTIA for the coastal waters. Then, WRF simulations were carried out for 1 year with a 2 km grid resolution and by using the FNL, OSTIA and MOSST datasets. The use of the OSTIA dataset for a WRF simulation was found to improve the accuracy when compared with the FNL dataset, and further improvement was obtained when the MOSST dataset was applied. The sensitivity of wind speed and wind energy density to SST is also discussed. We conclude that the use of an accurate SST is a key factor not only for realistic offshore wind simulations near the surface but also for accurate wind resource assessments at the hub height of wind turbines. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
48.
Familial male-limited precocious puberty (FMPP) is a form of luteinizing hormone-releasing hormone (LHRH)-independent isosexual precocious puberty caused by gain-of-function mutations of the luteinizing hormone/chorionic gonadotropin receptor (hLHR). The most common mutation is 1733 A>G, which causes substitution of Asp-578 by Gly. In this study, a male infant presented at the age of 20 months with accelerated sexual development was analyzed for the presence of activating mutations of the hLHR. Analysis of exon 11 of the hLHR gene by genomic polymerase chain reaction (PCR), asymmetric PCR, and dideoxy sequencing identified a single base substitution, 1734 T>A, which led to the replacement of Asp-578 by Glu. The same mutation was found in the mother. Expression of the mutated hLHR in HEK 293 cells demonstrated elevated basal levels of intracellular cAMP in the transfected cells confirming the constitutive activating nature of the mutated hLHR. A possible genotype-phenotype relationship of the hLHR mutations was examined by a comparison of the in vitro activities of the hLHRs carrying the Asp578Gly, Asp578Tyr, Asp578Trp, and Asp578Glu mutations in HEK 293 cells. A positive correlation between the size of the substituting amino acid and the basal level of intracellular cAMP of cells expressing the mutated receptor was demonstrated. 相似文献
49.
Martin Patrick Ongol Michiko Tanaka Teruo Sone Kozo Asano 《Food research international (Ottawa, Ont.)》2009,42(8):893-898
A real-time PCR method targeting a gene sequence encoding 16S rRNA processing protein, rimM, for specific detection of Streptococcus thermophilus was developed. The designed real-time PCR primers and probe were specific for S. thermophilus JCM20026, LMG6896, LMG18311, OJT101, OJT102 but not Enteroccocus spp., Lactococcus lactis subsp. lactis, and Streptococcus salivarius which are phylogenetically closely related to S. thermophilus and are difficult to identify using culture-based methods. The linear range of the developed real-time PCR method was from 2.7 to 8.6 log CFU ml?1 with an amplification efficiency of 96%. Minor differences (about 0.4 log CFU ml?1) were observed between counts of S. thermophilus obtained by culture and real-time PCR method in plain yoghurt and yoghurt containing fruits. Therefore, the developed real-time PCR method could be of potential application in specific detection and accurate enumeration of S. thermophilus in a wide range of dairy products. 相似文献
50.
S Koizumi M Ishiguro I Ohsawa T Morimoto C Takamura K Inoue S Kohsaka 《Canadian Metallurgical Quarterly》1998,123(8):1483-1489
1. The effects of secreted forms of beta-amyloid-precursor proteins (APP(S)s) on the intracellular Ca2+ concentration ([Ca2+]i) were investigated in rat cultured hippocampal neurones. APP695S, a secretory form of APP695, attenuated the increase in [Ca2+]i evoked by glutamate. In addition, APP695S itself evoked an increase in [Ca2+]i in 1 or 2 day-cultured hippocampal cells, but not in 7 to 13 day-cultured cells. 2. Eighty-one percent of neurones which were immunocytochemically positive for microtubule-associated protein 2 responded to APP695S with an increase in [Ca2+]i. 3. APP695S induced a transient rise in [Ca2+]i even in the absence of extracellular Ca2+ and produced an elevation in inositol-1,4,5-trisphosphate (IP3) in a concentration-dependent manner from 100 to 500 ng ml(-1). In the presence of extracellular Ca2+, APP695S caused a transient rise in [Ca2+]i followed by a sustained phase at high [Ca2+]i, suggesting Ca2+ entry from the extracellular space. 4. The [Ca2+]i elevation was mimicked by amino terminal peptides of APPs, but not by carboxy terminal peptides. 5. These results taken together suggest that APP695S induces an increase in [Ca2+]i in hippocampal neurones through an IP3-dependent mechanism that changes according to the stage of development. 相似文献