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排序方式: 共有516条查询结果,搜索用时 62 毫秒
71.
Shingo Saio Kanna Konishi Hirofumi Hohjoh Yuki Tamura Teruaki Masutani Arunasiri Iddamalgoda Masamitsu Ichihashi Hiroshi Hasegawa Ken-ichi Mizutani 《International journal of molecular sciences》2021,22(20)
Endothelial cells acquire different phenotypes to establish functional vascular networks. Vascular endothelial growth factor (VEGF) signaling induces endothelial proliferation, migration, and survival to regulate vascular development, which leads to the construction of a vascular plexuses with a regular morphology. The spatiotemporal localization of angiogenic factors and the extracellular matrix play fundamental roles in ensuring the proper regulation of angiogenesis. This review article highlights how and what kinds of extracellular environmental molecules regulate angiogenesis. Close interactions between the vascular and neural systems involve shared molecular mechanisms to coordinate developmental and regenerative processes. This review article focuses on current knowledge about the roles of angiogenesis in peripheral nerve regeneration and the latest therapeutic strategies for the treatment of peripheral nerve injury. 相似文献
72.
Shingo Kitamura Yoshiyuki Ishihara Toshiyuki Todaka Yoshiaki Inoue 《Electrical Engineering in Japan》1999,127(3):53-61
In this paper we propose an analytical method of DCBLM with polar anisotropic plastic rotor magnets. The orientation of the polar anisotropic plastic magnet is different for each part. In our method, the magnetic flux distribution of the injection mold for polar anisotropic plastic magnets is analyzed by FEM first. Next, the orientation is determined from the magnetic flux distribution. Finally, based on the latter, the nonlinear dynamic magnetic field of DCBLM is analyzed. The analytical value was in good agreement with the experimental value of magnetic flux distribution in the magnet unit and the characteristic of DCBLM. © 1999 Scripta Technica, Electr Eng Jpn, 127(3): 53–61, 1999 相似文献
73.
Fumio Yoshii Keizo Makuuchi Shingo Kikukawa Tadashi Tanaka Jun Saitoh Kiyohito Koyama 《应用聚合物科学杂志》1996,60(4):617-623
High-melt-strength polypropylene (PP) was achieved with irradiation by an electron beam generated from an accelerator in the presence of polyfunctional monomers (PFM). Among 16 PFMs, the relatively shorter molecular chain bifunctional monomers such as 1,4-butanediol diacrylate (BDDA) and 1,6-hexanediol diacrylate (HDDA) were the most effective for enhancing the melt strength of PP. The concentration and dose of the HDDA to obtain the high melt strength PP in irradiation under nitrogen gas atmosphere were 1.5 mmol/100 g PP and 1 kGy, respectively. DSC measurement and dynamic mechanical analysis showed that the thermal behavior of the high-melt-strength PP was different from that of the original PP. Crystallinity and crystallization temperature during cooling after heating were lower and higher in high melt strength PP than original PP, respectively. Elongational viscosity at 180°C of the high-melt-strength PP showed a remarkable increase at a certain elongational time with constant strain rate, demonstrating the typical property of high-melt-strength samples. This implies that a few higher molecular chains of PP, formed by intermolecular combination of its chain by HDDA in irradiation, give higher melt strength to induce entanglement of molecular chains. © 1996 John Wiley & Sons, Inc. 相似文献
74.
Shiori Mori Rina Fujiwara-Tani Shingo Kishi Takamitsu Sasaki Hitoshi Ohmori Kei Goto Chie Nakashima Yukiko Nishiguchi Isao Kawahara Yi Luo Hiroki Kuniyasu 《International journal of molecular sciences》2021,22(15)
β-Casomorphin-7 (BCM) is a degradation product of β-casein, a milk component, and has been suggested to affect the immune system. However, its effect on mucosal immunity, especially anti-tumor immunity, in cancer-bearing individuals is not clear. We investigated the effects of BCM on lymphocytes using an in vitro system comprising mouse splenocytes, a mouse colorectal carcinogenesis model, and a mouse orthotopic colorectal cancer model. Treatment of mouse splenocytes with BCM in vitro reduced numbers of cluster of differentiation (CD) 20+ B cells, CD4+ T cells, and regulatory T cells (Tregs), and increased CD8+ T cells. Administration of BCM and the CD10 inhibitor thiorphan (TOP) to mice resulted in similar alterations in the lymphocyte subsets in the spleen and intestinal mucosa. BCM was degraded in a concentration- and time-dependent manner by the neutral endopeptidase CD10, and the formed BCM degradation product did not affect the lymphocyte counts. Furthermore, degradation was completely suppressed by TOP. In the azoxymethane mouse colorectal carcinogenesis model, the incidence of aberrant crypt foci, adenoma, and adenocarcinoma was reduced by co-treatment with BCM and TOP. Furthermore, when CT26 mouse colon cancer cells were inoculated into the cecum of syngeneic BALB/c mice and concurrently treated with BCM and TOP, infiltration of CD8+ T cells was promoted, and tumor growth and liver metastasis were suppressed. These results suggest that by suppressing the BCM degradation system, the anti-tumor effect of BCM is enhanced and it can suppress the development and progression of colorectal cancer. 相似文献
75.
Ultramultiple roundtrips of surface acoustic wave on sphere realizing innovation of gas sensors 总被引:1,自引:0,他引:1
Yamanaka K Ishikawa S Nakaso N Takeda N Sim DY Mihara T Mizukami A Satoh I Akao S Tsukahara Y 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2006,53(4):793-801
A thin beam of wave usually diverges due to diffraction, which is a limitation of any device using such waves. However, a surface acoustic wave (SAW) on a sphere with an appropriate aperture does not diverge but is naturally collimated, realizing ultramultiple roundtrips along an equator of the sphere. This effect is caused by the balance between diffraction and focusing on a spherical surface, and it enables realization of high-performance ball SAW sensors. The advantage of ball SAW is most fully appreciated when applied to a very thin sensitive film for which the multiple-roundtrip enhances the sensitivity, but the attenuation loss is not very large. It is exemplified in a hydrogen gas sensor that realizes a wide sensing range of 10 ppm to 100% for the first time, and realizes relatively fast response time of 20 s without heating the sensitive film. 相似文献
76.
Transition of solidification mode and the as-cast γ grain structure in hyperperitectic carbon steels
Formation processes of as-cast γ grain structures during casting of hyperperitectic carbon steels with 0.15–0.45 mass% carbon concentrations have been studied by means of a rapid unidirectional solidification technique. In steels with 0.15–0.41 mass% carbon concentrations, coarse columnar γ grains (CCGs) with a minor axis diameter of 1–3 mm developed along the direction of temperature gradient. In a steel with 0.38 mass% carbon, importantly, columnar γ grains (CGs) whose minor axis diameter is less than 500 μm form before the formation of CCGs and the grain structure changes discontinuously from CG to CCG. The fraction of the CG region increases with an increase in the carbon concentration. In the samples with a carbon concentration higher than 0.43 mass%, the as-cast structure consists of CGs over almost the entire ingots. Analyses of the relation between γ grain and dendrite structures and their crystallographic orientations indicate that the formation of CGs originates from the primary solidification of γ phase instead of δ phase. This is supported by numerical analysis of the dendrite growths. 相似文献
77.
Shingo Wakahara Yuki FuruyaTakayuki Yanagida Yuui YokotaJan Pejchal Makoto SugiyamaNoriaki Kawaguchi Daisuke Totsuka Akira Yoshikawa 《Optical Materials》2012,34(4):729-732
0.1%, 0.5%, 1% and 3% Ce doped scintillation crystals based on NaF-CaF2-LuF3 solid solutions were grown from the melt using Micro-Pulling-Down (μ-PD) method. The grown crystals were transparent and their transmittance was approximately 80% for the wavelengths longer than 320 nm. Concerning the scintillation properties, radio-luminescence peaks of the crystals were detected at approximately 330 nm. The light yield of the crystals was also measured using γ-ray (137Cs and 22Na) as the excitation source. 相似文献
78.
Yoneoka S Lee J Liger M Yama G Kodama T Gunji M Provine J Howe RT Goodson KE Kenny TW 《Nano letters》2012,12(2):683-686
While the literature is rich with data for the electrical behavior of nanotransistors based on semiconductor nanowires and carbon nanotubes, few data are available for ultrascaled metal interconnects that will be demanded by these devices. Atomic layer deposition (ALD), which uses a sequence of self-limiting surface reactions to achieve high-quality nanolayers, provides an unique opportunity to study the limits of electrical and thermal conduction in metal interconnects. This work measures and interprets the electrical and thermal conductivities of free-standing platinum films of thickness 7.3, 9.8, and 12.1 nm in the temperature range from 50 to 320 K. Conductivity data for the 7.3 nm bridge are reduced by 77.8% (electrical) and 66.3% (thermal) compared to bulk values due to electron scattering at material and grain boundaries. The measurement results indicate that the contribution of phonon conduction is significant in the total thermal conductivity of the ALD films. 相似文献
79.
Stress granules (SGs) and processing bodies (P bodies) are cytoplasmic domains and play a role in the control of translation and mRNA turnover in mammalian cells subjected to environmental stress. Recent studies have revealed that SGs also form in the budding yeast Saccharomyces cerevisiae in response to glucose depletion and robust heat shock. However, information about the types of stress that cause budding yeast SGs is quite limited. Here we demonstrate that severe ethanol stress generates budding yeast SGs in a manner independent of the phosphorylation of eIF2α. The concentration that generated budding yeast SGs (>10%) was higher than that causing P bodies (>6%), and P bodies were assembled prior to SGs. As well as mammalian SGs, the assembly of budding yeast SGs under ethanol stress was blocked by cycloheximide. On the other hand, the budding yeast SGs caused by ethanol stress contained eIF3c but not eIF3a and eIF3b, although the eIF3 complex is a core constituent of mammalian SGs. Moreover, null mutants (pbp1Δ, pub1Δ and tif4632Δ) with a strong reduction in SG formation did not resume proliferation after the elimination of ethanol stress, indicating that the formation of budding yeast SGs might play a role in sufficient recovery from ethanol stress. 相似文献
80.
Bing Li Xianneng Li Shingo Mabu Kotaro Hirasawa 《IEEJ Transactions on Electrical and Electronic Engineering》2013,8(4):348-356
Genetic network programming (GNP) is a graph‐based evolutionary algorithm with fixed size, which has been proven to solve complicated problems efficiently and effectively. In this paper, variable size genetic network programming (GNPvs) with binomial distribution has been proposed, which will change the size of the individuals and obtain their optimal size during evolution. The proposed method will select the number of nodes to move from one parent GNP to another parent GNP during crossover to implement the new feature of GNP. The probability of selecting the number of nodes to move satisfies a binomial distribution. The proposed method can keep the effectiveness of crossover, improve the performance of GNP, and find the optimal size of the individuals. The well‐known testbed Tileworld is used to show the numerical results in the simulations. © 2013 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献