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排序方式: 共有421条查询结果,搜索用时 15 毫秒
61.
62.
Tatsuo Noritake Kazutoshi Miwa Masakazu Aoki Mitsuru Matsumoto Shin-ichi Towata Hai-Wen Li Shin-ichi Orimo 《International Journal of Hydrogen Energy》2013
Complex hydride Mg(BH4)(NH2), which consists of double anion BH4− and NH2−, was synthesized and the crystal structure was analyzed by synchrotron X-ray diffraction. The mixture sample of Mg(BH4)2 + Mg(NH2)2 prepared by ball milling was reacted and crystallized to Mg(BH4)(NH2) by heating at about 453 K. This crystal phase transforms into amorphous phase above 473 K and subsequently the dehydrogenation begins. The crystal structure of Mg(BH4)(NH2) was determined from measurement data at 453 K (chemical formula: Mg0.94(BH4)1(NH2)0.88, crystal system: tetragonal, space group: I41 (No.80), Z = 8, lattice constants: a = 5.814(1), c = 20.450(4) Å at 453 K). Mg(BH4)(NH2) is ionic crystal which the cation (Mg2+) and the anions (BH4− and NH2−) are stacking alternately along the c-axis direction. Two BH4− and two NH2− tetrahedrally coordinate around Mg2+ ion. 相似文献
63.
Kohei Yanagimoto Shin-ichi Sakamoto Yosuke Nakano Kentaro Kuroda Yoshiaki Watanabe 《能源与动力工程:英文版》2013,(8):1440-1447
Conventional thermoacoustic engines have a stack pore radius that is almost constant in the axial direction. Hence, a thermoacoustic engine is expected to improve the energy conversion efficiency using a multistage stack with multiple pore radii. The stack comprises several bundles of numerous narrow tubes with specified pore radii. The optimum pore radius of the stack is determined by the oscillation frequency and the temperature in the stack. Consequently, the suitable pore radius changes in the axial direction, because the temperature gradient exists along the stack axis. Therefore, a multistage stack with multiple pore radii is introduced, which achieves a desired optimum pore radius everywhere in the stack. The energy conversion efficiency of the multistage stack, which was studied experimentally for a straight-tube type thermoacoustic engine, was compared with that of a conventional single-stage stack. In these experiments, the improvement of the energy conversion efficiency was confirmed. A numerical method with the transmittance matrix to include the effect of a multistage stack was used, and good agreement between experimental and numerical results was obtained. The results make a future possibilities for stack design intended to higher thermoacoustic engine efficiency expect. 相似文献
64.
Kubota K Sato Y Suzuki Y Goto-Inoue N Toda T Suzuki M Hisanaga S Suzuki A Endo T 《Analytical chemistry》2008,80(10):3693-3698
Glycopeptides prepared from 1 nmol of a mixture of glycoproteins, transferrin, and ribonuclease B by lysylendopeptidase digestion were isolated by lectin and cellulose column chromatographies, and then they were analyzed by matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry and MALDI-quadrupole ion trap (QIT)-TOF mass spectrometry which enables the performance of MS ( n ) analysis. The lectin affinity preparation of glycopeptides with Sambucus nigra agglutinin and concanavalin A provides the glycan structure outlines for the sialyl linkage and the core structure of N-glycans. Such structural estimation was confirmed by MALDI-TOF MS and MALDI-QIT-TOF MS/MS. Amino acid sequences and location of glycosylation sites were determined by MALDI-QIT-TOF MS/MS/MS. Taken together, the combination of lectin column chromatography, MALDI-TOF MS, and MALDI-QIT-TOF MS ( n ) provides an easy way for the structural estimation of glycans and the rapid analysis of glycoproteomics. 相似文献
65.
Sasaki K Morita M Matsumoto N Sasaki D Hirano S Ohmura N Igarashi Y 《Journal of Bioscience and Bioengineering》2012,114(1):64-69
The aim of this study was to show the effectiveness of the membrane free bioelectrochemical system (BES) using three electrodes on inhibition of methanogenesis and construction of hydrogen fermentation from the artificial garbage slurry. The electrical redox-potential on the working electrode was adjusted to -1.0V (vs. Ag/AgCl) that has positive effect on methanogenesis. The redox-potential on the counter electrode was measured to be 1.6V. The pH in the effluents was 5.5-6.4. Hydrogen production rate at the cathode side was similar to that at the anode side and much higher than that calculated from current, and reached a maximum of 2445±815 (average±standard deviation) mL?L(-1)?d(-1) at an organic loading rate of 58.7g dichromate chemical oxygen demand per L d(-1). Methane production was negligible throughout the experiment. Acetate and butyrate were the main products of the fermentation using a BES; these offered favorable conditions for hydrogen production. The bacterial community in the bioelectrochemical hydrogen fermentor differed from that in the methanogenic seed sludge and included hitherto unknown species. These results show that high redox-potential on the anodic electrode and acidic pH in the membrane free BES can be utilized for hydrogen fermentation from the artificial garbage slurry by avoiding methanogenesis. 相似文献
66.
Shin-ichi Satake Takafuni AnrakuFumihiko Tamoto Kazuho SatoTomoaki Kunugi 《Microelectronic Engineering》2011,88(8):1875-1877
This paper reports on a new technology of simultaneous measurements of micro-fluorescent-particle position in 3D and of temperature field with high time-resolution. The technology to measure both velocity and temperature field is based on the simultaneity of micro digital holographic particle tracking velocimetry (micro-DHPTV) and laser-induced fluorescence (LIF). 相似文献
67.
Hiromi Nabeshi Tomoaki Yoshikawa Akihiro Arimori Tokuyuki Yoshida Saeko Tochigi Toshiro Hirai Takanori Akase Kazuya Nagano Yasuhiro Abe Haruhiko Kamada Shin-ichi Tsunoda Norio Itoh Yasuo Yoshioka Yasuo Tsutsumi 《Nanoscale research letters》2011,6(1):1-6
In this study, complexes composed of poly-l-tyrosine (pLT) and single-walled carbon nanotubes (SWCNTs) were produced and the dispersibility of the pLT/SWCNT complexes in water by measuring the ζ potential of the complexes and the turbidity of the solution were investigated. It is found that the absolute value of the ζ potential of the pLT/SWCNT complexes is as high as that of SWCNTs modified with double-stranded DNA (dsDNA) and that the complexes remain stably dispersed in the water at least for two weeks. Thermogravimetry analysis (TGA) and visualization of the surface structures of pLT/SWCNT complexes using an atomic force microscope (AFM) were also carried out. 相似文献
68.
Shin-ichi Shimakawa Yasuhiro Hashimoto Shigeo Hayashi Takuya Satoh Takayuki Negami 《Solar Energy Materials & Solar Cells》2008,92(9):1086-1090
Annealed Zn1−xMgxO/Cu(In,Ga)Se2 (CIGS) interfaces have been characterized by ultraviolet light excited time-resolved photoluminescence (TRPL). The TRPL lifetime of the Zn1−xMgxO/CIGS film increased on increasing the annealing temperature to 250 °C, whereas the TRPL lifetime of the CdS/CIGS film had little change by annealing at temperatures lower than 200 °C. This is attributed to the recovery of physical damages by annealing, induced by sputtering of the Zn1−xMgxO film. The TRPL lifetime abruptly decreased with annealing at 300 °C. The diffusion of excess Zn from the Zn1−xMgxO film into the CIGS interface is clearly observed in secondary ion mass spectroscopy (SIMS) depth profiles. These results indicate that excess Zn at the vicinity of the CIGS surface acts as non-radiative centers at the interface. The TRPL lifetime of the Zn1−xMgxO/CIGS film annealed at 250 °C reached values to be comparable to that of the as-deposited CdS/CIGS film. Performance of the Zn1−xMgxO/CIGS cells varied with the annealing temperature in the same manner as the TRPL lifetime. The highest efficiency of the Zn1−xMgxO/CIGS solar cells was achieved for annealing at 250 °C. The results of the TRPL lifetime on annealing show that the cell efficiency is strongly influenced by the Zn1−xMgxO/CIGS interface states related to the damages and diffusion of Zn. 相似文献
69.
基于物性推算法的膜分离材料设计 总被引:5,自引:3,他引:2
针对渗透汽化或蒸汽渗透法进行有机溶剂混合物分离,首次提出基于物性推算法的膜分离材料设计方法。基于溶解-扩散机理模型,使用统计热力学和状态方程式为基础的GCLF-EOS模型进行溶解度计算,自由体积模型推算扩散系数,同时考虑填充型复合膜的基膜影响,建立膜渗透通量计算模型。溶解性、扩散性的物性推算结果,较好地再现芳香族有机溶剂在高分子材料中的溶解和扩散行为,复合膜的渗透通量计算值与实验测定结果基本一致。由于计算模型中不包含任何从实验直接回归参数,本设计法具有可预测性和普遍适用性。 相似文献
70.
Jain Gu Seonggon Lee Seunghwan Eom Hosung Ki Eun Hyuk Choi Yunbeom Lee Shunsuke Nozawa Shin-ichi Adachi Jeongho Kim Hyotcherl Ihee 《International journal of molecular sciences》2021,22(18)
The halogen elimination of 1,2-diiodoethane (C2H4I2) and 1,2-diiodotetrafluoroethane (C2F4I2) serves as a model reaction for investigating the influence of fluorination on reaction dynamics and solute–solvent interactions in solution-phase reactions. While the kinetics and reaction pathways of the halogen elimination reaction of C2H4I2 were reported to vary substantially depending on the solvent, the solvent effects on the photodissociation of C2F4I2 remain to be explored, as its reaction dynamics have only been studied in methanol. Here, to investigate the solvent dependence, we conducted a time-resolved X-ray liquidography (TRXL) experiment on C2F4I2 in cyclohexane. The data revealed that (ⅰ) the solvent dependence of the photoreaction of C2F4I2 is not as strong as that observed for C2H4I2, and (ⅱ) the nongeminate recombination leading to the formation of I2 is slower in cyclohexane than in methanol. We also show that the molecular structures of the relevant species determined from the structural analysis of TRXL data provide an excellent benchmark for DFT calculations, especially for investigating the relevance of exchange-correlation functionals used for the structural optimization of haloalkanes. This study demonstrates that TRXL is a powerful technique to study solvent dependence in the solution phase. 相似文献