全文获取类型
收费全文 | 5155篇 |
免费 | 135篇 |
国内免费 | 26篇 |
专业分类
电工技术 | 413篇 |
综合类 | 17篇 |
化学工业 | 1466篇 |
金属工艺 | 136篇 |
机械仪表 | 138篇 |
建筑科学 | 189篇 |
矿业工程 | 1篇 |
能源动力 | 244篇 |
轻工业 | 506篇 |
水利工程 | 19篇 |
石油天然气 | 7篇 |
无线电 | 286篇 |
一般工业技术 | 914篇 |
冶金工业 | 185篇 |
原子能技术 | 214篇 |
自动化技术 | 581篇 |
出版年
2023年 | 27篇 |
2022年 | 28篇 |
2021年 | 95篇 |
2020年 | 52篇 |
2019年 | 62篇 |
2018年 | 76篇 |
2017年 | 63篇 |
2016年 | 112篇 |
2015年 | 79篇 |
2014年 | 152篇 |
2013年 | 320篇 |
2012年 | 186篇 |
2011年 | 306篇 |
2010年 | 257篇 |
2009年 | 279篇 |
2008年 | 314篇 |
2007年 | 262篇 |
2006年 | 203篇 |
2005年 | 220篇 |
2004年 | 176篇 |
2003年 | 161篇 |
2002年 | 165篇 |
2001年 | 105篇 |
2000年 | 96篇 |
1999年 | 97篇 |
1998年 | 105篇 |
1997年 | 73篇 |
1996年 | 71篇 |
1995年 | 55篇 |
1994年 | 81篇 |
1993年 | 69篇 |
1992年 | 55篇 |
1991年 | 75篇 |
1990年 | 53篇 |
1989年 | 77篇 |
1988年 | 65篇 |
1987年 | 39篇 |
1986年 | 73篇 |
1985年 | 56篇 |
1984年 | 53篇 |
1983年 | 57篇 |
1982年 | 60篇 |
1981年 | 47篇 |
1980年 | 42篇 |
1979年 | 41篇 |
1978年 | 41篇 |
1977年 | 28篇 |
1976年 | 29篇 |
1975年 | 18篇 |
1973年 | 17篇 |
排序方式: 共有5316条查询结果,搜索用时 156 毫秒
101.
Lydie du Bousquet Masahide Nakamura Ben Yan Hiroshi Igaki 《Innovations in Systems and Software Engineering》2009,5(3):181-196
A home network system consists of multiple networked appliances, intended to provide more convenient and comfortable living
for home users. Before being deployed, one has to guarantee the correctness, the safety, and the security of the system. Here,
we present the approach chosen to validate the Java implementation of a home network system. We rely on the Java Modelling
Language to formally specify and validate an abstraction of the system.
This is a substantially revised version of our paper that appeared in the proceedings of the Workshop On Leveraging Applications
of Formal Methods, Verification and Validation (ISoLA), Poitiers-Futuroscope, France, December 2007. 相似文献
102.
A novel method for three-dimensional observation of the vascular networks in the whole mouse brain 总被引:1,自引:0,他引:1
A novel method for acquiring serial images suitable for three-dimensional reconstruction of vascular networks in the whole brain of mouse was developed. The brain infused with a White India ink-gelatin solution was fixed and embedded in paraffin containing Sudan Black B through xylene also containing Sudan Black B. Each sliced surface of the paraffin block was coated with liquid paraffin and its image was serially acquired. Coating with liquid paraffin extremely improved the quality of the image. The series of serial images was free of distortion and a three-dimensional image was reconstructed without the problem of the alignment and registration of adjacent images. The volume-rendered image indicated three-dimensional distribution of blood vessels in a whole brain. No ghost or shadow was observed on a volume-rendered image of the White India ink-gelatin infused brain. The z-axial resolution examined on the orthogonal sections reconstituted from serial images obtained at an interval of 5 mum showed no cross talk, indicating that the z-axial resolution was no larger than 5 mum. A proper understanding of the vascular system in a whole brain is indispensable to reveal the development of the vascular system in the brain of normal and genetically manipulated mouse and vascular alterations in pathological situation, such as stroke and neurodegenerative disease. Although simple and inexpensive, this method will provide fundamental information on the vascular system in a whole brain. 相似文献
103.
Kojima Masami Tasaki Takafumi Suzuki Yukihisa Kamijo Toshio Hada Aki Kik Alfred Ikehata Masateru Sasaki Hiroshi 《Journal of Infrared, Millimeter and Terahertz Waves》2022,43(3-4):260-271
Journal of Infrared, Millimeter, and Terahertz Waves - Millimeter waves (MMW) absorbed by skin or cornea may induce damage by heat. We have developed a 60 GHz MMW exposure-induced eye... 相似文献
104.
105.
106.
The effect of small dose of topiroxostat on serum uric acid in patients receiving hemodialysis
下载免费PDF全文
![点击此处可从《Hemodialysis international. International Symposium on Home Hemodialysis》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Yume Nagaoka Yoshiko Tanaka Hiroshi Yoshimoto Rie Suzuki Kakei Ryu Mio Ueda Minako Akiyama Miho Nagai Yoshitaka Miyaoka Eiichiro Kanda Shinnichi Iwai Michio Nagaoka Yoshihiko Kanno 《Hemodialysis international. International Symposium on Home Hemodialysis》2018,22(3):388-393
Introduction : Topiroxostat, a recently developed xanthine oxidase inhibitor, is expected to have fewer adverse effects than allopurinol because it has different mechanism of action from alloprinol. However, its dosage, usage and safety have not been established in patients with impaired renal function or those undergoing dialysis at the development since no studies was conducted in these patients. Methods : Cross over clinical trial using 3 months of allopurinol and topiroxostat on 27 maintain Japanese HD patients were carried out. The effects on oxidative stress status of both drugs were also evaluated by measuring oxidation reduction potential. Findings : Twenty‐five of twenty‐seven patients completed study. The mean serum uric acid levels in the topiroxostat‐treated arm was significantly lower than it in the allopurinol‐treated arm time‐dependently (P < 0.0001). Corrected oxidative stress ratio defined as biological antioxidant potential/diacron reactive oxygen metabolites was significantly increased in topiroxostat‐arm (*P = 0.0035), but not in allopurinol‐arm (P = 0.1429). No significant difference was seen in diacron reactive oxygen metabolites, biological antioxidant potential, static oxidation‐reduction potential, and capacity oxidation‐reduction potential between pre and post treatment of both drugs. Discussion : It is suggested that a low dose of topiroxostat decreased serum uric acid sufficiently to maintain it below 7.0 mg/dL in patients receiving hemodialysis. 相似文献
107.
Hiroshi Kametani 《Metallurgical and Materials Transactions B》1998,29(6):1261-1267
Data concerning the length of longitudinal cracks on the surface of continuously cast steel slabs were collected from two
plants. The data were analyzed to find the relation between crack length and crack frequency. The analysis revealed the following.
相似文献
(1) |
After normalization to eliminate the effect of different casting conditions, the fractal relation characterizing the normalized
cumulative frequency distribution (N (m−2)) and the crack length (L (mm)) of the primary surface cracks could be represented by the equation |
|
(2) | The values for γ varied over a wide range, but remained constant throughout a heat and were the same for both the upper and lower faces of the slab. | |
(3) | It was found that in some instances, when L exceeded a critical value (L c), the value of L became δ times longer than the length predicted by the previous distribution. This increase in L was ascribed to secondary growth of the cracks. This occurred more frequently on the lower, rather than on the upper, face of the slab. The product of L c and δ was approximately constant. The formation of the surface cracks is discussed in view of the fractal phenomena. |
108.
C. Bäuerle N. Mori G. Kurata Hiroshi Fukuyama 《Journal of Low Temperature Physics》1998,113(5-6):927-932
Scanning tunneling microscopy (STM) studies of two-dimensional (2D) cryocrystals
4
He, Kr, Xe) physisorbed on graphite surfaces are presented. Individual helium atoms, usually thought to be invisible with STM, were recently observed on graphite surfaces at a density corresponding to the
commensurate solid. Here we show that a local elastic deformation seems to be the principal mechanism responsible to render the atoms visible. Recent tight-binding calculations of the local density of states (LDOS) of graphite which predict the appearance of an energy gap support this picture. I-z curve measurements for the case of
4
He show a sharp drop (increase) of the tunneling current I at a certain tip-surface distance z during retraction (approach) of the tip. This drop (increase) may be associated with the tunneling of a single He adatom, opening new possibilities to study the quantum tunneling of atoms via STM. 相似文献
109.
Kazushi Yawata Daisuke Ito Hiroki Ikegami Hidehiko Ishimoto Hiroshi Fukuyama 《Journal of Low Temperature Physics》1998,113(5-6):769-774
Experimental methods and preliminary results of high-precision measurements of the
3
He melting curve in high magnetic fields have been described. The purpose of this work is twofold. One is to establish a reliable millikelvin temperature scale in high fields (T 10 mK, B 15 T), The other is to investigate a high field region of the magnetic phase diagram of solid
3
He by measuring the melting pressure down to temperatures below 1 mK. Besides the two superfluid transitions, the phase transition temperatures between the spin ordered solid and the paramagnetic solid, T
HFP
, were determined at B = 12 and 10 T with good accuracy, which is an extension of previous measurements up to 8 T. The present T
HFP
(B) line can not be scaled to that at a higher density with a single Grüneisen parameter, indicating a variation of density dependencies of the multiple-spin exchange interactions. 相似文献
110.
Hiroyuki Ishida Author Vitae Tomokazu Takahashi Author Vitae Author Vitae Hiroshi Murase Author Vitae 《Pattern recognition》2010,43(8):2799-2806
We propose a novel sequence alignment algorithm for recognizing handwriting gestures by a camera. In the proposed method, an input image sequence is aligned to the reference sequences by phase-synchronization of analytic signals which are transformed from original feature values. A cumulative distance is calculated simultaneously with the alignment process, and then used for the classification. A major benefit of this method is that over-fitting to sequences of incorrect categories is restricted. The proposed method exhibited higher recognition accuracy in handwriting gesture recognition, compared with the conventional dynamic time warping method which explores optimal alignment results for all categories. 相似文献