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71.
72.
Nishikino M Hasegawa N Kawachi T Yamatani H Sukegawa K Nagashima K 《Applied optics》2008,47(8):1129-1134
We have improved a highly coherent x-ray laser at 13.9 nm using an oscillator-amplifier configuration. To improve a high-brilliance x-ray laser, we adopted traveling wave pumping for the amplifier target and rotated the amplifier target 3-4 mrad in the counterclockwise direction. Thereby, a seed x-ray laser can be amplified by medium plasma of the amplifier target with a high gain coefficient. The amplified x-ray laser has the output energy of approximately 1.3 microJ, corresponding to a large photon flux of 6.5 x 10(10) photons/pulse and a high peak brilliance of 5 x 10(26) photons/(s x mm(2) x mrad(2) x 0.01% bandwidth). 相似文献
73.
We present a detailed experimental study of a new through-focus technique to measure critical dimension linewidth with nanometer sensitivity using a bright field optical microscope. This method relies on analyzing intensity gradients in optical images at different focus positions, here defined as the focus metric (FM) signature. The contrast of an optical image of a structured target, where a particular structure is repeated several times, varies greatly as it is moved through-focus if the spacing between the structures is such that the scattered field from the features interferes. Complex, distinguishable through-focus optical response occurs under this condition giving rise to the formation of several cyclic high and low contrast images. As a result it exhibits several FM signature peaks as opposed to a single FM peak for structures nearly isolated. This complex optical behavior is very sensitive to the dimensions of the target geometry. By appropriately analyzing the through-focus optical image, information can be obtained regarding the target. An array of lines is used as a structured target. Linewidth measurements were made by using experimental through-focus optical data obtained using a bright field microscope and simulated optical data. The optical results are compared with reference metrology tools such as a critical dimension atomic force microscope and critical dimension scanning electron microscope. 相似文献
74.
Shinji Kanehashi Kota Yokoyama Risa Masuda Takashi Kidesaki Kazukiyo Nagai Tetsuo Miyakoshi 《应用聚合物科学杂志》2013,130(4):2468-2478
Novel organic solvent‐free bio‐based epoxy resin for coating was prepared from cashew nut shell liquid which is one of renewable resources. The epoxy coating was fabricated by the reaction between amine compounds and epoxy cardanol prepolymer (ECP). The drying, physical, and thermal properties of the epoxy were investigated and compared with those of the commercial cashew coating. The ECP was synthesized by thermal polymerization under the various conditions. Based on the FT‐IR analysis, hydroxyl and carbonyl groups were generated, and viscosity increased with increasing heating temperature and time. On the other hand, the NMR analysis showed decrease in the degree of unsaturation in the side group of cardanol. Based on these results, the polymerization of the ECP could be autoxidized in the unsaturated group in the side chains. The drying time until harden dry of the ECP coating took about 2.5 h at room temperature, which is faster than that of the commercial cashew coating. This is because that the curing of ECP coating was based on the prepolymer (i.e., high molecular weight) and crosslink reaction between epoxy and amine groups. The ECP coating was rubbery state due to the flexible side chains of cardanol. Furthermore, the ECP coating improved chemical stability compared with the commercial cashew. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 2468–2478, 2013 相似文献
75.
76.
Internal cooling passages and thermal barrier coatings (TBCs) are presently used to control metal temperatures in gas turbine
blades. Functionally graded materials (FGMs), which are typically mixtures of ceramic and metal, have been proposed for use
in turbine blades because they possess smooth property gradients thereby rendering them more durable under thermal loads.
In the present work, a functionally graded model of an air-cooled turbine blade with airfoil geometry conforming to the NACA0012
is developed which is then used in a finite element algorithm to obtain a non-linear steady state solution to the heat equation
for the blade under convection and radiation boundary conditions. The effects of external gas temperature, coolant temperature,
surface emissivity changes and different average ceramic/metal content of the blade on the temperature distributions are examined.
Simulations are also carried out to compare cooling effectiveness of functionally graded blades with that of blades having
TBC. The results highlight the effect of including radiation in the simulation and also indicate that external gas temperature
influences the blade heat transfer more strongly. It is also seen that graded blades with about 70% ceramic content can deliver
better cooling effectiveness than conventional blades with TBC. 相似文献
77.
Kota Kawai Hiroshi Sagara Kenji Takeshita Masahiro Kawakubo Hidekazu Asano Yaohiro Inagaki 《Journal of Nuclear Science and Technology》2018,55(10):1130-1140
Looking ahead to final disposal of high-level radioactive waste arising from further utilization of nuclear energy, the effects of high burn-up of light-water reactors (LWR) with UO2 and MOX fuel and extended cooling period of spent fuel on waste management and disposal were discussed. It was assumed that the waste loading of waste glass is restricted by three factors: heat generation rate, MoO3 content, and platinum group metal content. As a result of evaluation for effects of extended cooling period, the waste loading of waste glass from both UO2 and MOX spent fuel could be increased in the current vitrification technology. For the storage of waste glass from MOX spent fuel with higher waste loading, however, those waste glass require long storage period prior to geological disposal because decay heat of 241Am contributes significantly. Therefore, the evaluation of effects of Am separation on the storage period was performed. Furthermore, heat transfer calculation was carried out in order to evaluate the temperature of buffer material in a geological repository. The results showed, 70 to 90% of Am separation is sufficiently effective in terms of thermal feasibility of a repository. 相似文献
78.
Traffic management for TCP/IP over satellite ATM networks 总被引:1,自引:0,他引:1
Goyal R. Jain R. Goyal M. Fahmy S. Vandalore B. Kota S. 《Communications Magazine, IEEE》1999,37(3):56-61
Several Ka-band satellite systems have been proposed that will use ATM technology to seamlessly transport Internet traffic. The ATM UBR, GFR, and ABR service categories have been designed for data. However, several studies have reported poor TCP performance over satellite ATM networks. We describe techniques to improve TCP performance over satellite ATM networks. We first discuss the various design options available for TCP end systems, IP-ATM edge devices, as well as ATM switches for long-latency connections. We discuss buffer management policies, guaranteed rate services, and the virtual source/virtual destination option in ATM. We present a comparison of ATM service categories for TCP transport over satellite links. The main goal of this article is to discuss design and performance issues for the transport of TCP over UBR, GFR, and ABR services for satellite ATM networks 相似文献
79.
Shin-ichi Morita Kota Tanimura Yasutaka Hayamizu Takanobu Yamada Akihiko Horibe Naoto Haruki Toshiaki Setoguchi 《热科学学报(英文版)》2016,25(6):558-563
This paper deals with the output improvement of heating and cooling cycle by using the work-fluid including phase change material.The experimental study is carried out by heat exchange between work-fluid and heat transfer surface.The work-fluid is flown to a high temperature or a low temperature heat transfer surface from the narrow path.In order to increase the amount of the heat transmission,a trace of Diethylether(boiling point 34.8 ℃),as a phase change material(PCM),is added to the work-fluid.The parameters of the experiment are additive amount of PCM,the rotational speed of the displacer piston and the temperature of heat transfer surface.It is clarified that the increasing of engine cycle output is brought by the PCM addition.The effect of PCM addition is evaluated by output ratio which is defined from the experimental cycle output data.The requirements for acquiring the increasing effect of output by adding PCM are clarified. 相似文献
80.
Adam Kilgarriff Frieda Charalabopoulou Maria Gavrilidou Janne Bondi Johannessen Saussan Khalil Sofie Johansson Kokkinakis Robert Lew Serge Sharoff Ravikiran Vadlapudi Elena Volodina 《Language Resources and Evaluation》2014,48(1):121-163
We present the KELLY project and its work on developing monolingual and bilingual word lists for language learning, using corpus methods, for nine languages and thirty-six language pairs. We describe the method and discuss the many challenges encountered. We have loaded the data into an online database to make it accessible for anyone to explore and we present our own first explorations of it. The focus of the paper is thus twofold, covering pedagogical and methodological aspects of the lists’ construction, and linguistic aspects of the by-product of the project, the KELLY database. 相似文献