全文获取类型
收费全文 | 954篇 |
免费 | 12篇 |
国内免费 | 1篇 |
专业分类
电工技术 | 78篇 |
化学工业 | 222篇 |
金属工艺 | 34篇 |
机械仪表 | 13篇 |
建筑科学 | 6篇 |
能源动力 | 38篇 |
轻工业 | 33篇 |
水利工程 | 2篇 |
石油天然气 | 1篇 |
无线电 | 124篇 |
一般工业技术 | 122篇 |
冶金工业 | 190篇 |
原子能技术 | 13篇 |
自动化技术 | 91篇 |
出版年
2022年 | 17篇 |
2021年 | 22篇 |
2020年 | 5篇 |
2019年 | 5篇 |
2018年 | 11篇 |
2017年 | 11篇 |
2016年 | 14篇 |
2015年 | 10篇 |
2014年 | 14篇 |
2013年 | 24篇 |
2012年 | 37篇 |
2011年 | 42篇 |
2010年 | 32篇 |
2009年 | 34篇 |
2008年 | 28篇 |
2007年 | 34篇 |
2006年 | 32篇 |
2005年 | 24篇 |
2004年 | 20篇 |
2003年 | 31篇 |
2002年 | 16篇 |
2001年 | 16篇 |
2000年 | 15篇 |
1999年 | 27篇 |
1998年 | 84篇 |
1997年 | 57篇 |
1996年 | 38篇 |
1995年 | 28篇 |
1994年 | 29篇 |
1993年 | 27篇 |
1992年 | 13篇 |
1991年 | 14篇 |
1990年 | 12篇 |
1989年 | 16篇 |
1988年 | 7篇 |
1987年 | 9篇 |
1986年 | 9篇 |
1985年 | 7篇 |
1984年 | 13篇 |
1983年 | 9篇 |
1982年 | 5篇 |
1981年 | 8篇 |
1980年 | 6篇 |
1979年 | 4篇 |
1978年 | 4篇 |
1977年 | 7篇 |
1976年 | 10篇 |
1975年 | 6篇 |
1974年 | 5篇 |
1973年 | 9篇 |
排序方式: 共有967条查询结果,搜索用时 0 毫秒
11.
Tsuyoshi Asakawa Hidefumi Takeda Shigeyoshi Miyagishi Morie Nishida 《Journal of the American Oil Chemists' Society》1986,63(11):1479-1482
The qualitative and quantitative determination of anionic surfactants (sodium and lithium alkylsulfate, sodium dodecylbenzenesulfonate,
sodium di-2-ethylhexyl sulfosuccinate, sodium and lithium perfluoroalkylcarboxylate, and lithium perfluorooctanesulfonate)
were investigated by a capillary tube isotachophoresis using a potential gradient detector. The leading electrolyte solution
was the mixture of acetonitrile and aqueous solution of histidine buffer containing calcium chloride. The terminating electrolyte
solution was the aqueous solution of sodium octanoate. These electrolytes were effective for the analysis of the mixtures
of strongly acidic surfactants. 相似文献
12.
Requirements and microstructural design criteria for employing silicon nitride in long-term structural applications at elevated temperatures are discussed according to fracture mechanics concepts. Three least engineering parameters are considered: lifetime, flaw-tolerance and deformation under stress. “Ductile” materials are found by exploitation of small-scale crack-tip yielding which arises from the softening of their grain-boundary phase. These materials, however, are likely to exhibit poor deformation resistance. Materials with a “strong” grain boundary generally show a superior deformation behaviour but are liable to brittle fracture and static-fatigue strength degradation unless shielding mechanisms in the crack-wake be operative. The present analysis evaluates and compares these two classes of materials and the respective approaches commonly followed for their densification. 相似文献
13.
Yasunobu Hitaka Yoshito Tanaka Yutaka Tanaka Ken Ichiryu 《Artificial Life and Robotics》2009,14(4):494-497
A tripod parallel mechanism consists of three links of fixed length and a rigid platform, and these are connected by revolute
joints. The platform can achieve sixdegrees-of-freedom (6-DOF) motion by the coordinated movement of the bottom ends of the
three links on a horizontal plane. This mechanism has advantages over the more common six extendible parallel manipulators.
It has a much larger work space and a simple structure. In this article, we show that the vector analysis for this tripod
parallel mechanism and the derivation of the positions of the three bottom ends of the links in an arbitrary attitude of platform
can be found by inverse kinematics and the conditions of geometrical constraint. Then, by a numerical simulation, the trajectories
of the bottom ends of the three links are shown. 相似文献
14.
T Yamagata J Nishida S Tanaka R Sakai K Mitani M Yoshida T Taniguchi Y Yazaki H Hirai 《Canadian Metallurgical Quarterly》1996,16(4):1283-1294
We have isolated a novel cDNA clone encoding interferon (IFN) consensus sequence-binding protein in adult T-cell leukemia cell line or activated T cells (ICSAT); this protein is the human homolog of the recently cloned Pip/LSIRF. ICSAT is structurally most closely related to the previously cloned ICSBP, a member of the IFN regulatory factor (IRF) family of proteins that binds to interferon consensus sequences (ICSs) found in many promoters of the IFN-regulated genes. Among T-cell lines investigated, ICSAT was abundantly expressed in human T-cell leukemia virus type 1 (HTLV-1)-infected T cells. When the HTLV-1 tax gene was expressed or phorbol myristake acetate-A23187 stimulation was used, ICSAT expression was induced in Jurkat cells which otherwise do not express ICSAT. When the binding of ICSAT to four different ICSs was tested, the relative differences in binding affinities for those ICSs were determined. To study the functional role of ICSAT, we performed cotransfection experiments with the human embryonal carcinoma cell line N-Tera2. ICSAT was demonstrated to possess repressive function over the gene activation induced by IFN stimulation or by IRF-1 cotransfection. Such repressive function is similar to that seen in IRF-2 or ICSBP. However, we have found that ICSAT has a different repressive effect from that of IRF-2 or ICSBP in some IFN-responsive reporter constructs. These results suggest that a novel mechanism of gene regulation by "differential repression" is used by multiple members of repressor proteins with different repressive effects on the IFN-responsive genes. 相似文献
15.
Socializing artifacts as a half mirror of the mind 总被引:1,自引:1,他引:0
In the near future, our life will normally be surrounded with fairly complicated artifacts, enabled by the autonomous robot
and brain–machine interface technologies. In this paper, we argue that what we call the responsibility flaw problem and the
inappropriate use problem need to be overcome in order for us to benefit from complicated artifacts. In order to solve these
problems, we propose an approach to endowing artifacts with an ability of socially communicating with other agents based on
the artifact-as-a-half-mirror metaphor. The idea is to have future artifacts behave according to the hybrid intention composed
of the owner’s intention and the social rules. We outline the approach and discuss its feasibility together with preliminary
work.
相似文献
Toyoaki Nishida (Corresponding author)Email: |
Ryosuke NishidaEmail: |
16.
K. ôno S. Kobayasi M. Shinohara K. Asahi H. Ishimoto N. Nishida M. Imaizumi A. Nakaizumi J. Ray Y. Iseki S. Takayanagi K. Terui T. Sugawara 《Journal of Low Temperature Physics》1980,38(5-6):737-745
Two-stage nuclear demagnetization has been performed using PrCu6 and Cu as coolants. The Cu nuclear stage reached temperatures as low as 10 K with a rate of temperature rise of less than a few K/h. The corresponding conduction electron temperature is estimated to be less than 50 K. A nuclear orientation thermometer of Al
54Mn has been successfully used to measure temperatures down to 10 K.Supported by the Japan Society for the Promotion of Science. 相似文献
17.
18.
Humans and animals seek appropriate solutions to novel problems through trial-and-error (TE) actions and observation of their outcomes. Once an individual has obtained the knowledge (rule) to solve a problem, knowledge-based (KB) actions may be applied in a stereotypical manner. Solutions can thus be based on TE or KB actions. To characterize this learning process at the behavioral level, we developed a new cognitive task for a laboratory monkey (Macaca fuscata) to perform. In this task, a search array consisting of six elements of different colors was presented, one of which was the behaviorally relevant target. The target color was changed unpredictably with no instruction or signal, requiring the monkey to use a TE search strategy to find the target color. We found that once the monkey identified the relevant color by chance after a color change, correct performance increased in a step-like manner and at the same time, other response properties (reaction time and color-choice tendency) also changed discontinuously. These step-like alternations in behavioral performance may be attributed to the subject’s switching between TE and KB search strategies in the two phases. The present study has therefore provided behavioral evidence for the timing and manner of switching between search strategies during the process of updating knowledge. 相似文献
19.
20.
Katsumasa Tsurushima Masanobu Tsubaki Tomoya Takeda Takuya Matsuda Akihiro Kimura Honoka Takefuji Akane Okada Chiaki Sakamoto Toshihiko Ishizaka Shozo Nishida 《International journal of molecular sciences》2022,23(15)
Triple-negative breast cancer (TNBC) has the poorest prognosis of all breast cancer subtypes. Recently, the activation of NF-κB, which is involved in the growth and survival of malignant tumors, has been demonstrated in TNBC, suggesting that NF-κB may serve as a new therapeutic target. In the present study, we examined whether dimethyl fumarate (DMF), an NF-κB inhibitor, induces apoptosis in TNBC cells and enhances the apoptosis-inducing effect of paclitaxel and adriamycin. Cell survival was analyzed by the trypan blue assay and apoptosis assay. Protein detection was examined by immunoblotting. The activation of NF-κB p65 was correlated with poor prognosis in patients with TNBC. DMF induced apoptosis in MDA-MB-231 and BT-549 cells at concentrations that were non-cytotoxic to the normal mammary cell line MCF-10A. Furthermore, DMF inhibited NF-κB nuclear translocation and Survivin, XIAP, Bcl-xL, and Bcl-2 expression in MDA-MB-231 and BT-549 cells. Moreover, DMF enhanced the apoptosis-inducing effect of paclitaxel and adriamycin in MDA-MB-231 cells. These findings suggest that DMF may be an effective therapeutic agent for the treatment of TNBC, in which NF-κB is constitutively active. DMF may also be useful as an adjuvant therapy to conventional anticancer drugs. 相似文献