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101.
Suning Luo Koichi Okada Shigemi Kohiki Fuki Tsutsui Hirokazu Shimooka Fumiya Shoji 《Materials Letters》2009,63(6-7):641-643
Polycrystalline thin films of indium tin oxide sputter-deposited in the working gas containing hydrogen of 0.3–1.5% exhibited transmittance of ≥ 80% for visible lights and blue-shift of ≥ 0.1 eV in the optical absorption energy. The film deposited in the gas containing hydrogen of 1% demonstrated almost flat temperature-dependent resistivity and the lowest resistivity of ≈ 1.5 × 10? 4 Ω cm at room temperature. The carrier density showed an inverse V-shaped behavior with the maximum at the hydrogen concentration of 1%. The mobility stayed at almost constant below the hydrogen concentration of 1% and dropped rather rapidly above 1%. 相似文献
102.
多晶YAG陶瓷的制备及力学性能 总被引:25,自引:7,他引:18
本实验采用共沉淀方法制备YAG微粉 ,Al和Y元素分布均匀 ,在 90 0℃煅烧 2h即可全部转变为YAG粉体 ,无过渡相 .15 0 0℃热压 1h可获得致密烧结体 ,其抗弯强度为 2 45MPa ,断裂韧性为 2 .0MPa·m1 /2 ,晶粒大小为 3~ 6μm ;14 0 0℃放电等离子烧结 5min可获得相对密度为 93 %的烧结体 ,其抗弯强度为 3 4 8MPa,断裂韧性为 2 .1MPa·m1 /2 ,晶粒大小为 1~ 2 μm . 相似文献
103.
Masahiro Hatasa Sumiko Yoshida Hirokazu Takahashi Kenichi Tanaka Yoshihito Kubotsu Yujin Ohsugi Takaharu Katagiri Takanori Iwata Sayaka Katagiri 《International journal of molecular sciences》2021,22(7)
Periodontal disease is an inflammatory disease caused by pathogenic oral microorganisms that leads to the destruction of alveolar bone and connective tissues around the teeth. Although many studies have shown that periodontal disease is a risk factor for systemic diseases, such as type 2 diabetes and cardiovascular diseases, the relationship between nonalcoholic fatty liver disease (NAFLD) and periodontal disease has not yet been clarified. Thus, the purpose of this review was to reveal the relationship between NAFLD and periodontal disease based on epidemiological studies, basic research, and immunology. Many cross-sectional and prospective epidemiological studies have indicated that periodontal disease is a risk factor for NAFLD. An in vivo animal model revealed that infection with periodontopathic bacteria accelerates the progression of NAFLD accompanied by enhanced steatosis. Moreover, the detection of periodontopathic bacteria in the liver may demonstrate that the bacteria have a direct impact on NAFLD. Furthermore, Porphyromonas gingivalis lipopolysaccharide induces inflammation and accumulation of intracellular lipids in hepatocytes. Th17 may be a key molecule for explaining the relationship between periodontal disease and NAFLD. In this review, we attempted to establish that oral health is essential for systemic health, especially in patients with NAFLD. 相似文献
104.
Computational Visual Media - In many-light rendering, a variety of visual and illumination effects, including anti-aliasing, depth of field, volumetric scattering, and subsurface scattering, are... 相似文献
105.
Sub-boundaries in3He and4He single crystal and their migration below 1K observed by X-ray topography
Tetsuo Nakajima Joji Ohta Ichiro Yonenaga Hirokazu Koizumi Izumi Iwasa Haruhiko Suzuki Takayoshi Suzuki Hideji Suzuki 《Journal of Low Temperature Physics》1995,101(3-4):701-706
The observation of alterations in crystal structure at ultra-low temperatures by X-ray diffraction, made possible by the realization of synchrotron radiation use after a quarter of this century, plays an important role in obtaining an understanding of the base structure of solids. For that, two types of3He-4He dilution refrigerators with a modified version of the top-loading facilities were installed at the BL-3C2 and 6C1 stations of the Photon Factory. In BL-3C2, the behaviors of lattice defects in solid helium have been studied by X-ray topography. In this note, the migrations of sub-boundaries in3He and4He single-crystals are reported as being the result of an annealing effect. After annealing hcp4He single crystals for 80min at 0.5K, no change in crystallographic orientations could be easily observed from white SR X-ray topographs. In the same type topographs of bcc3He single crystals after annealing for several hours at 03K, migration of sub-boundaries were conspicuously discerned. 相似文献
106.
Hirokazu Yoshizawa Gabor C. Temes 《Analog Integrated Circuits and Signal Processing》2006,48(3):267-270
This paper describes a high-precision switched-capacitor (SC) track-and-hold amplifier (THA) stage. It uses a novel continuous-time
correlated double sampling (CDS) scheme to desensitize the operation to amplifier imperfections. Unlike earlier predictive-CDS
THAs, the circuit does not need a sample-and-held input signal for its operation. During the tracking period, an auxiliary
continuous-time signal path is established, which predicts the output voltage during the holding period. This allows accurate
operation even for low amplifier gains and large offsets over a wide input frequency range. Extensive simulations were performed
to compare the performance of the proposed THA with earlier circuits utilizing CDS. The results verify that its operation
is far more robust than that of any previously described THA. 相似文献
107.
This paper proposes a nonlinear circuit that generates chaotic oscillations. The proposed nonlinear circuit includes a nonlinear capacitor and a nonlinear inductor by using Generalized Impedance Converters. Both computational experiments and experiments on real circuits show that the region for chaotic oscillation is very wide, demonstrating that the proposed circuit is effective as a chaos generator. © 2004 Wiley Periodicals, Inc. Electr Eng Jpn, 150(2): 35–42, 2005; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10361 相似文献
108.
Hirokazu Ikeda 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》1995,360(3):598-606
A general technique to generate electronic noise was developed in a time-domain approach with the aid of a deconvolution technique in a discrete-time sampling system. We found that the technique is applicable even for a system in which the electronic-noise charge is not well defined. The generated noise train was reconstructed in terms of a sample-correlated function and the frequency spectrum. 相似文献
109.
Hirokazu Ezawa Masaharu Seto Masahiro Miyata Hiroshi Tazawa 《Microelectronics Reliability》2003,43(3):473-479
It is confirmed that stencil printing with a novel developed printable polyimide paste can be used for polymer film deposition on LSI wafers. A thick polyimide film with openings for solder ball bumping can be deposited on all of the LSIs on a wafer by stencil printing at one time. This stencil printing process does not need an expensive lithography process, providing cost-effective wafer-level chip scale packages (WLCSPs). In this study, a novel polyimide paste was tailored to have a higher thixotropy ratio than conventional printable polyimide materials. The novel printable polyimide paste shows that the viscosity ratio of more than 3.5 at the shear rate of 1 to 10 s−1 and that the viscosity increases rapidly after the shear rate is lowered. Fine spaces of 40 μm between 250 μm openings were obtained for 10 μm thick polyimide films on Si wafers. It has been also confirmed that the new paste shows the variation range of 30 μm at the opening size of 385 μm within 100 continuously printed wafers. Even after the new paste was shear-thinned repeatedly, rheological behavior of the new paste was not changed. This robustness leads to higher efficiency of the materials for mass-producing. From the reliability viewpoint of the printed polyimide films, no peelings were observed on plasma-CVD SiN films after the pressure cooker test under the condition of 127 °C and 0.25 MPa with the humidity of 100% for 300 h. The optimal stencil printing process using the novel developed paste will lead to significant cost reduction of a patterned polymer deposition process. Finally, WLCSPs using the stencil printing of the new polyimide paste have been demonstrated for SRAM LSIs on 8-in. wafers. 相似文献
110.
Uncertainty‐conscious methodology for process performance assessment in biopharmaceutical drug product manufacturing 下载免费PDF全文
Gioele Casola Hirokazu Sugiyama Christian Siegmund Markus Mattern 《American Institute of Chemical Engineers》2018,64(4):1272-1284
This work presents an uncertainty‐conscious methodology for the assessment of process performance—for example, run time—in the manufacturing of biopharmaceutical drug products. The methodology is presented as an activity model using the type 0 integrated definition (IDEF0) functional modeling method, which systematically interconnects information, tools, and activities. In executing the methodology, a hybrid stochastic–deterministic model that can reflect operational uncertainty in the assessment result is developed using Monte Carlo simulation. This model is used in a stochastic global sensitivity analysis to identify tasks that had large impacts on process performance under the existing operational uncertainty. Other factors are considered, such as the feasibility of process modification based on Good Manufacturing Practice, and tasks to be improved is identified as the overall output. In a case study on cleaning and sterilization processes, suggestions were produced that could reduce the mean total run time of the processes by up to 40%. © 2017 American Institute of Chemical Engineers AIChE J, 64: 1272–1284, 2018 相似文献