全文获取类型
收费全文 | 438篇 |
免费 | 7篇 |
国内免费 | 1篇 |
专业分类
电工技术 | 54篇 |
化学工业 | 95篇 |
金属工艺 | 14篇 |
机械仪表 | 9篇 |
建筑科学 | 4篇 |
能源动力 | 8篇 |
轻工业 | 30篇 |
水利工程 | 2篇 |
无线电 | 50篇 |
一般工业技术 | 61篇 |
冶金工业 | 71篇 |
原子能技术 | 9篇 |
自动化技术 | 39篇 |
出版年
2023年 | 1篇 |
2022年 | 7篇 |
2021年 | 8篇 |
2020年 | 2篇 |
2019年 | 4篇 |
2018年 | 7篇 |
2017年 | 2篇 |
2016年 | 10篇 |
2015年 | 3篇 |
2014年 | 5篇 |
2013年 | 22篇 |
2012年 | 10篇 |
2011年 | 22篇 |
2010年 | 13篇 |
2009年 | 17篇 |
2008年 | 17篇 |
2007年 | 14篇 |
2006年 | 15篇 |
2005年 | 14篇 |
2004年 | 8篇 |
2003年 | 19篇 |
2002年 | 13篇 |
2001年 | 7篇 |
2000年 | 8篇 |
1999年 | 14篇 |
1998年 | 28篇 |
1997年 | 23篇 |
1996年 | 15篇 |
1995年 | 11篇 |
1994年 | 13篇 |
1993年 | 14篇 |
1992年 | 6篇 |
1991年 | 5篇 |
1990年 | 10篇 |
1989年 | 9篇 |
1988年 | 5篇 |
1987年 | 5篇 |
1986年 | 4篇 |
1985年 | 8篇 |
1984年 | 3篇 |
1983年 | 6篇 |
1982年 | 1篇 |
1981年 | 3篇 |
1980年 | 1篇 |
1979年 | 3篇 |
1978年 | 2篇 |
1977年 | 3篇 |
1976年 | 4篇 |
1972年 | 1篇 |
1965年 | 1篇 |
排序方式: 共有446条查询结果,搜索用时 31 毫秒
1.
An alternating dispersion arrangement is proposed for soliton systems with dispersion compensation to improve soliton stabilisation. A transmission experiment at 20 Gbit/s over 2600 km long singlemode fibre was successfully demonstrated by employing this novel dispersion arrangement 相似文献
2.
3.
Tetsuya Murai Yoshiharu Sato Germano Resconi Michinori Nakata 《Electronic Notes in Theoretical Computer Science》2003,82(4):186
The concept of granular computing is applied to Aristotle's categorical syllogism. Such kind of reasoning is called granular reasoning in this paper. For the purpose, two operations called zooming in & out are introduced to reconstruct granules of possible worlds. 相似文献
4.
5.
The laryngeal chemoreflex (LCR) is a potentially life-threatening reflex that is elicited in immature animals by the topical application of water to the laryngeal mucosa. The reflex response is characterized by immediate apnea and laryngeal adduction and delayed cardiovascular instability. The cardiorespiratory changes of the LCR may be life-threatening, particularly in very immature animals such as piglets under 2 weeks of age. The afferent and efferent limbs of the LCR are mediated through the vagus nerve, but the neuromediators responsible for the reflex changes have not yet been clearly elucidated. Previous agonist and antagonist studies in immature dogs demonstrated that substance P, a sensory tachykinin, mediates the life-threatening esophagolaryngeal adductor reflex elicited by distal esophageal sensory nerve stimulation. This study was conducted to determine if substance P also plays a role in mediating the LCR. The LCR response was compared before and after treatment with intravenous substance P antagonist (Pfizer CP-96,345-1) in eight piglets (mean 27.7 days of age). The laryngeal and cardiovascular responses of the animals following intravenous administration of the tachykinins substance P, neurokinin A, and neurokinin B were also assessed. Pretreatment with substance P antagonist did not alter the LCR's duration of apnea (p > .10), laryngeal adductor response, or early change in mean arterial pressure (p > .10), although the early maximal heart rate response was significantly altered (p < .01). Intravenous substance P, neurokinin A, and neurokinin B did not reproduce the laryngeal respiratory response of the LCR. We conclude that substance P, neurokinin A, and neurokinin B are not key neurotransmitters of the LCR. 相似文献
6.
Kanichi Kamiya Toshinobu Yoko Keiji Moroishi Kazumasa Matusita Sumio Sakka 《Journal of Materials Science》1986,21(1):131-136
The behaviour of copper ions in low thermal expansion glass-ceramics prepared from Cu2O · Al2O3 ·nSiO2 glasses, or in-spodumene type Cu2O · Ae2O3 ·nSiO2 crystals included in the glass-ceramics on heating in air was investigated. On hewing at 300 to 500° C, the copper ions behaved as in the corresponding glasses. Cuprous ions in the glass-ceramics or-spondumene type crystals were oxidized into the cupric state, and at the same time an equal amount of cuprous ions to those oxidized were expelled out of the specimen for the requirement of electrical charge neutrality and then reacted with oxygen to form CuO on the surface. The oxidation of cuprous ions and the decrease of the copper content of the-spondumene type crystals brought about a considerable decrease in the lattice spooings. 相似文献
7.
For the purpose of synthesizing standards to be used in the quantification of TAG hydroperoxides, three TAG (1,2-dioleoyl-3-palmitoylglycerol,
1-oleoyl-2-linoleoyl-3-palmitoylglycerol, and triolein) monohydroperoxides were chemically synthesized as authentic specimens.
TAG were prepared by using a simple condensation in pyridine of glycerol and the corresponding acid chlorides. These TAG were
then converted into monohydroperoxides by a photosensitized peroxidation. The synthesized monohydroperoxides were analyzed
by normal-phase and RP-HPLC. The results of normal-phase HPLC analysis showed that monohydroperoxides from a corresponding
TAG were a mixture of regioisomers. In RP-HPLC, however, the regioisomers of monohydroperoxides were not separated and gave
a single peak, which may improve the sensitivity for the detection of TAG monohydroperoxides. In this study TAG monohydroperoxide
standards were synthesized; these will be useful for the study of yet unknown biological and pathological roles of TAG hydroperoxides. 相似文献
8.
Kazumasa Ide Masatoshi Watanabe Masaki Sato Miyoshi Takahashi Noriyoshi Takahash 《Electrical Engineering in Japan》1995,115(3):108-119
This paper describes relationships between characteristics of a magnetically anisotropic slot wedge and voltage higher harmonics in an ac exciting synchronous generator terminal due to permeance ripple caused by an open-slot-type rotor. From the relationships obtained, practical guidelines were formulated for machine designs applying the magnetically anisotropic slot wedge. The results are as follows.
- 1 (1) Equivalent permeability of the magnetically anisotropic slot wedge became isotropic wedge permeability for air-gap flux ripple.
- 2 (2) Two ways were identified to reduce voltage-higher harmonics by using the slot wedges.
- 3 (3) The level of leakage flux passing through the anisotropic slot wedge was determined only by its permeability in the width direction.
- 4 (4) Effectiveness of the magnetic anisotropic slot wedges inserted into the stator slots was verified from experimental results using a model machine of the open- slot-type rotor.
9.
Kazuo Nakajima Satoshi Ono Ryota Murai Yuzuru Kaneko 《Journal of Electronic Materials》2016,45(6):2837-2846
10.