全文获取类型
收费全文 | 753篇 |
免费 | 17篇 |
国内免费 | 4篇 |
专业分类
电工技术 | 24篇 |
综合类 | 2篇 |
化学工业 | 116篇 |
金属工艺 | 14篇 |
机械仪表 | 24篇 |
建筑科学 | 18篇 |
能源动力 | 33篇 |
轻工业 | 80篇 |
水利工程 | 2篇 |
石油天然气 | 1篇 |
无线电 | 67篇 |
一般工业技术 | 119篇 |
冶金工业 | 187篇 |
原子能技术 | 16篇 |
自动化技术 | 71篇 |
出版年
2023年 | 3篇 |
2022年 | 3篇 |
2021年 | 11篇 |
2020年 | 7篇 |
2019年 | 5篇 |
2018年 | 6篇 |
2017年 | 5篇 |
2016年 | 12篇 |
2015年 | 5篇 |
2014年 | 25篇 |
2013年 | 43篇 |
2012年 | 34篇 |
2011年 | 41篇 |
2010年 | 18篇 |
2009年 | 26篇 |
2008年 | 31篇 |
2007年 | 23篇 |
2006年 | 30篇 |
2005年 | 23篇 |
2004年 | 16篇 |
2003年 | 14篇 |
2002年 | 25篇 |
2001年 | 25篇 |
2000年 | 21篇 |
1999年 | 24篇 |
1998年 | 76篇 |
1997年 | 30篇 |
1996年 | 35篇 |
1995年 | 17篇 |
1994年 | 13篇 |
1993年 | 19篇 |
1992年 | 13篇 |
1991年 | 4篇 |
1990年 | 12篇 |
1989年 | 6篇 |
1988年 | 3篇 |
1987年 | 4篇 |
1986年 | 7篇 |
1985年 | 7篇 |
1984年 | 4篇 |
1983年 | 5篇 |
1982年 | 4篇 |
1981年 | 2篇 |
1980年 | 3篇 |
1979年 | 10篇 |
1978年 | 2篇 |
1977年 | 3篇 |
1976年 | 11篇 |
1975年 | 3篇 |
1973年 | 3篇 |
排序方式: 共有774条查询结果,搜索用时 15 毫秒
41.
近几年来,各医院把建设数字化医院作为首位,确保系统的稳定可靠和安全运行成为数字化建设的重中之重.结合瑞金医院在实际工作中采取的安全方法及措施,阐述了如何构建医院信息系统的安全运行体系,提高医疗服务质量. 相似文献
42.
Sazia Parvin Farookh Khadeer Hussain Omar Khadeer Hussain Thandar Thein Jong Sou Park 《Computing》2013,95(10-11):927-948
With the rapid growth of wireless communication, the deployment of cyber-physical system (CPS) is increasing day by day. As a cyber physical system involves a tight coupling between the physical and computational components, it is critical to ensure that the system, apart from being secure, is available for both the cyber and physical processes. Traditional methods have generally been employed to defend an infrastructure system against physical threats. However, this does not guarantee that the availability of the system will always be high. In this paper, we propose a multi-cyber (computational unit) framework to improve the availability of CPS based on Markov model. We evaluate the effectiveness of our proposed framework in terms of availability, downtime, downtime cost and reliability of the CPS framework. 相似文献
43.
A. Inoue T. Ekimoto H. M. Kimura Y. Masumoto T. Masumoto N. Miyake 《Metallurgical and Materials Transactions A》1987,18(3):377-383
Amorphous spherical particles with diameters of 0.5 to 1.4 mm have been prepared by melt ejecting Ni-rich Ni-Pd-P alloys into stirred cold water with 1 vol pct surfactive agent. The sphericity of the amorphous particles defined by the difference in diameter was better than 98 pct. Particle diameters (d) are 2 to 3 times larger than the orifice diameter (2r) of the quartz nozzle. The size ratio has been interpreted by the Raplace’s relation (d = 4r) derived from the assumption that an internal pressure of molten alloy is equal between cylindrical stream and spherical droplet. From the result that no spherical amorphous particles are formed in the cold water without surfactive agent, a significant decrease in the surface tension of coolant by the addition of surfactive agent is essential in the formation of spherical liquid particles from the ejected melt stream. The amorphous particles with diameters below about 1.0 mm exhibit hardness, crystallization temperature, and heat of crys-tallization similar to those from the amorphous ribbon with about 40 μm thickness. However, the onset temperature and heat of relaxation are lower by 16 K (4.2 pct) and larger by 130 J/mol (13 pct), respectively, for the particles. It is thus concluded that the amorphous spherical particles have the same thermal stability as that of the amorphous ribbon and its structure is in a more disordered state as compared with the ribbon sample. 相似文献
44.
45.
Miyake J. Maeda T. Nishimichi Y. Katsura J. Taniguchi T. Yamaguchi S. Edamatsu H. Watari S. Takagi Y. Tsuji K. Kuninobu S. Cox S. Duschatko D. MacGregor D. 《Solid-State Circuits, IEEE Journal of》1990,25(5):1199-1206
A 1-million transistor 64-b microprocessor has been fabricated using 0.8-μm double-metal CMOS technology. A 40-MIPS (million instructions per second) and 20-MFLOPS (million floating-point operations per second) peak performance at 40 MHz is realized by a self-clocked register file and two translation lookaside buffers (TLBs) with word-line transition detection circuits. The processor contains an integer unit based on the SPARC (scalable processor architecture) RISC (reduced instruction set computer) architecture, a floating-point unit (FPU) which executes IEEE-754 single- and double-precision floating-point operations a 6-KB three-way set-associative physical instruction cache, a 2-KB two-way set-associative physical data cache, a memory management unit that has two TLBs, and a bus control unit with an ECC (error-correcting code) circuit 相似文献
46.
47.
N. V. Kozyrev G. V. Sakovich Sen Tchel Sou 《Combustion, Explosion, and Shock Waves》2005,41(5):589-590
The synthesis of detonation diamonds from a mixture of RDX labeled by C14 isotope with soot was studied experimentally. It was shown that a considerable portion of the diamonds (24.7 ± 3.4)% are
formed from the carbon of RDX molecules. The degree of conversion of the carbon atoms of soot to the diamond phase is (16.0
± 1.6)%.
__________
Translated from Fizika Goreniya i Vzryva, Vol. 41, No. 5, pp. 117–118, September–October, 2005. 相似文献
48.
S.K. Chan S.K. Lok G. Wang Y. Cai N. Wang K.S. Wong I.K. Sou 《Journal of Electronic Materials》2008,37(9):1433-1437
Ultrathin ZnS nanowires (NWs) were grown on a sapphire (0001) substrate at 430°C by the molecular-beam epitaxy (MBE) technique
using self-assembled Au droplets as the catalyst. It was found that these NWs mainly consist of the cubic phase but a small
portion was in the hexagonal phase. The analysis of the temperature-dependent band-edge (BE) emission of these NWs and that
of a ZnS thin film revealed that the energy shift of the interband transition on temperature in ZnS is mainly attributed to
the electron–phonon interactions. The observed blue shift of the BE emission of ZnS NWs could be quantitatively explained
by the confinement of the excited excitons in the NW geometry. 相似文献
49.
Shinji Tsuneyuki Hikaru Kitamura Tadashi Ogitsu Takashi Miyake 《Journal of Low Temperature Physics》2001,122(3-4):291-296
Quantum distributions of protons in three high-pressure phases of solid molecular hydrogen are investigated by the first-principles path integral molecular dynamics (FP-PIMD) method, in which interatomic forces are calculated precisely based on the density functional theory. The distributions have entirely different symmetries from those predicted by conventional simulation with classical treatment of protons. Especially in phase II, we found that molecular rotation is hindered by quantum fluctuation of protons, having a strong resemblance to a quantum distribution of impurity muonium in crystalline silicon. The mechanism of this “quantum localization” is clarified by a detailed study of the potential energy surface for the molecular rotation. 相似文献
50.