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181.
182.
We calculate the thermal conductivity of solid
3
He in U2D2 phase. In this system, magnons are the dominant heat carriers. The experiment by Feng et al. shows that scattering magnon by some kind of magnetic defects becomes important at low temperature. We suppose the defects are the magnetic plane defects (MPD) which are originated by lattice dislocation and calculate the thermal conductivity with Kapitza Resistance Model (KRM). 相似文献
183.
Data mining assisted by theoretical calculations for improving dye-sensitized solar cell performance
Hitoshi Kusama Yoshinari Konishi Hideki Sugihara 《Solar Energy Materials & Solar Cells》2007,91(1):76-78
Data mining using experimental data and information generated from theoretical calculations is proposed to study dye-sensitized solar cells, which are complex systems. This method led to new knowledge about the influence of imidazole derivatives as additives in an electrolytic solution on the cell performance. It was found that the solar energy conversion efficiency is strongly correlated to the Mulliken charge of the carbon atom at position 4 in the imidazole group. This result indicates that data mining assisted by theoretical calculations should facilitate the rate that cell performance is improved. 相似文献
184.
Crystallographic quality and the lattice constant of ZnSe crystals grown from Te/ Se solutions by the temperature gradient
solution growth method were evaluated by using a high resolution x-ray diffractometer. The full width at half maximum of the
x-ray rocking curve was 5.7 sec, a value almost equivalent to that of GaAs. The distribution of crystallographic properties
along the growth direction was nearly the same excepting just on the heat-sink. The accurate lattice constant of the ZnSe
crystal measured by this system was 5.6700 ± 0.000025 A. 相似文献
185.
YC Yoo K Yoshimatsu Y Koike R Hatsuse K Yamanishi O Tanishita J Arikawa I Azuma 《Canadian Metallurgical Quarterly》1998,16(2-3):216-224
The adjuvant effect of two lipophilic derivatives of muramyl dipeptide (MDP), B30-MDP and MDP-Lys(L18), on the ability of an inactivated vaccine of B-1 virus (B-1 vaccine) to induce immune response against Hantavirus causing hemorrhagic fever with renal syndrome (HFRS) was examined. When mice were immunized subcutaneously (s.c.) twice at 2-week intervals with B-1 vaccine admixed with or without 100 micrograms mouse-1 of B30-MDP (B-1/B30-MDP) or MDP-Lys(L18) [B-1/MDP-Lys(L18)], mice immunized with B-1/B30-MDP as well as B-1/MDP-Lys(L18) showed significantly higher indirect fluorescent antibody (IFA) titers against HFRS virus than mice immunized with B-1 vaccine alone. Both mice treated with B-1/B30-MDP and B-1/MDP-Lys(L18) also exhibited significantly higher neutralizing antibody titers against HFRS virus than mice immunized with B-1 vaccine alone during 3-9 weeks after the primary immunization. The evaluation of antibody-producing cells by enzyme-linked immunospot (ELISPOT) assay on week 4 revealed that both MDP derivatives enhanced the number of HFRS virus-specific IgG1 and IgM antibody-producing cells. Furthermore, mice treated with B-1/B30-MDP as well as B-1/MDP-Lys(L18) showed a higher level of Th-2 type cytokines, IL-4 and IL-6, in sera than mice treated with B-1 alone. In an in-vitro analysis of T lymphocyte proliferation to baculovirus-expressed recombinant nucleocapsid protein (rNP) of Hantaan 76-118 strain, the splenocytes of mice treated with B-1/B30-MDP and B-1/MDP-Lys(L18) on week 4 showed a significantly higher proliferating activity than those treated with B-1 vaccine alone. In addition, when mice were immunized once with B-1 vaccine admixed with or without B30-MDP and MDP-Lys(L18) and followed by intrafootpad (i.f.) injection of B-1 vaccine on day 7, mice immunized with B-1/B30-MDP and B-1/MDP-Lys(L18) induced a higher delayed-type hypersensitivity (DTH) reaction than mice immunized with B-1 vaccine alone. These results suggest that B30-MDP and MDP-Lys(L18) are useful immunoadjuvants to enhance the ability of inactivated B-1 vaccine to induce a humoral and cellular response to HFRS virus. 相似文献
186.
The purpose of this paper is to design congestion controllers for TCP/AQM networks using state predictive control and to illustrate the effectiveness of the resulting congestion controllers via SIMULINK and the ns‐2 simulator. Linearized models of TCP/AQM networks can be simply described as linear systems with information delay. Using state predictive control, these linear systems with an information delay are equivalent to linear systems with no delay. Thus, congestion controllers (AQM mechanisms) can be designed by using linear control theory. In this paper, LQ control with an observer is adopted for linear systems with no delay which describe linearized systems of TCP/AQM networks. Finally the designed state predictive controllers using LQ control with an observer are implemented and some simulation results obtained with SIMULINK and the ns‐2 simulator are presented. © 2006 Wiley Periodicals, Inc. Electr Eng Jpn, 156(3): 41–47, 2006; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20405 相似文献
187.
Acetylene Vacuum Carburizing 总被引:1,自引:0,他引:1
HitoshiIwata 《材料热处理学报》2004,25(5):370-374
Almost 30 years has passed since the publication of materials on vacuum carburizing technology, and is attracting a great deal of attention as a technology capable of being used as a substitute for gas carburizing technology.However, the technology was not popular except in specific fields. The main reason for this is due to a variety of harmful influences accompanying the sooting problems caused by CH4 or C3H8. We have succeeded in that the occurrence of sooting was suppressed by utilizing acetylene, at extremely low pressure for carburizing (below 1 kPa). This process is now showing the excellent quality and prospects for this technology in terms of quality, economy and safety. At present almost 70 practical mass production furnaces are used in production lines, in Japan and abroad. At this time, we will report summary of the present acetylene vacuum carburizing process and the actual results obtained by these acetylene vacuum carburizing furnaces for mass production. 相似文献
188.
In this paper, we consider a dynamical model of computer networks and derive a synthesis method for congestion control. First, we present a model of TCP/AQM (Transmission Control Protocol/Active Queue Management) as a dynamical model of computer networks. The dynamical model of TCP/AQM networks consists of models of TCP window size, queue length, and AQM mechanisms. Second, we propose to describe the dynamical model of TCP/AQM networks as linear systems with self‐scheduling parameters, which also depend on information delay. Here we focus on the constraints on the maximum queue length and TCP window size, which are the network resources in TCP/AQM networks. We derive TCP/AQM networks as the LPV system (linear parameter varying system) with information delay and self‐scheduling parameter. We design a memoryless state feedback controller of the LPV system based on a gain‐scheduling method. Finally, the effectiveness of the proposed method is evaluated by using MATLAB and the well‐known ns‐2 simulator (Network Simulator Version 2). © 2004 Wiley Periodicals, Inc. Electr Eng Jpn, 149(1): 61–68, 2004; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10341 相似文献
189.
Y Azuma Y Oue H Kanatani T Ohta M Kiyoki K Komoriya 《Canadian Metallurgical Quarterly》1998,286(1):128-135
Providencia stuartii contains a chromosomal 2'-N-acetyltransferase [AAC(2')-Ia] involved in the O acetylation of peptidoglycan. The AAC(2')-Ia enzyme is also capable of acetylating and inactivating certain aminoglycosides and confers high-level resistance to these antibiotics when overexpressed. We report the identification of a locus in P. stuartii, designated aarF, that is required for the expression of AAC(2')-Ia. Northern (RNA) analysis demonstrated that aac(2')-Ia mRNA levels were dramatically decreased in a P. stuartii strain carrying an aarF::Cm disruption. The aarF::Cm disruption also resulted in a deficiency in the respiratory cofactor ubiquinone. The aarF locus encoded a protein that had a predicted molecular mass of 62,559 Da and that exhibited extensive amino acid similarity to the products of two adjacent open reading frames of unknown function (YigQ and YigR), located at 86 min on the Escherichia coli chromosome. An E. coli yigR::Kan mutant was also deficient in ubiquinone content. Complementation studies demonstrated that the aarF and the E. coli yigQR loci were functionally equivalent. The aarF or yigQR genes were unable to complement ubiD and ubiE mutations that are also present at 86 min on the E. coli chromosome. This result indicates that aarF (yigQR) represents a novel locus for ubiquinone production and reveals a previously unreported connection between ubiquinone biosynthesis and the regulation of gene expression. 相似文献
190.
Tohyama S. Masubuchi K. Konuma K. Azuma H. Tanabe A. Utsumi H. Teranishi N. Takano E. Yamagata S. Hijikawa M. Sahara H. Muramatsu T. Seki T. Ono T. Goto H. 《Electron Devices, IEEE Transactions on》1995,42(8):1433-1440
A back surface illuminated 130/spl times/130 pixel PtSi Schottky-barrier (SB) IR-CCD image sensor has been developed by using new wiring technology, referred to as CLOSE Wiring, CLOSE Wiring, designed to effectively utilize the space over the SB photodiodes, brings about flexibility in clock line designing, high fill factor, and large charge handling capability in a vertical CCD (VCCD). This image sensor uses a progressive scanned interline-scheme, and has a 64.4% fill factor in a 30 /spl mu/m/spl times/30 /spl mu/m pixel, a 3.9 mm/spl times/3.9 mm image area, and a 5.5 mm/spl times/5.5 mm chip size. The charge handling capability for the 3.3 /spl mu/m wide VCCD achieves 9.8/spl times/10/sup 5/ electrons, The noise equivalent temperature difference obtained was 0.099 K for operation at 120 frames/sec with a 50 mm f/1.3 lens.<> 相似文献