全文获取类型
收费全文 | 457篇 |
免费 | 8篇 |
国内免费 | 1篇 |
专业分类
电工技术 | 27篇 |
化学工业 | 96篇 |
金属工艺 | 15篇 |
机械仪表 | 14篇 |
建筑科学 | 13篇 |
能源动力 | 16篇 |
轻工业 | 40篇 |
水利工程 | 1篇 |
石油天然气 | 6篇 |
无线电 | 22篇 |
一般工业技术 | 109篇 |
冶金工业 | 75篇 |
原子能技术 | 15篇 |
自动化技术 | 17篇 |
出版年
2023年 | 2篇 |
2022年 | 10篇 |
2021年 | 8篇 |
2020年 | 2篇 |
2019年 | 10篇 |
2018年 | 8篇 |
2017年 | 5篇 |
2016年 | 5篇 |
2015年 | 2篇 |
2014年 | 15篇 |
2013年 | 24篇 |
2012年 | 19篇 |
2011年 | 18篇 |
2010年 | 15篇 |
2009年 | 18篇 |
2008年 | 26篇 |
2007年 | 22篇 |
2006年 | 14篇 |
2005年 | 16篇 |
2004年 | 26篇 |
2003年 | 19篇 |
2002年 | 13篇 |
2001年 | 4篇 |
2000年 | 9篇 |
1999年 | 8篇 |
1998年 | 30篇 |
1997年 | 17篇 |
1996年 | 15篇 |
1995年 | 11篇 |
1994年 | 13篇 |
1993年 | 5篇 |
1992年 | 8篇 |
1991年 | 1篇 |
1990年 | 1篇 |
1989年 | 4篇 |
1988年 | 3篇 |
1987年 | 9篇 |
1986年 | 3篇 |
1985年 | 4篇 |
1984年 | 4篇 |
1983年 | 1篇 |
1982年 | 1篇 |
1981年 | 1篇 |
1980年 | 5篇 |
1979年 | 1篇 |
1978年 | 3篇 |
1977年 | 2篇 |
1976年 | 4篇 |
1975年 | 1篇 |
1972年 | 1篇 |
排序方式: 共有466条查询结果,搜索用时 31 毫秒
51.
Naoto Kakuta Katsuya Kondo Atsushi Ozaki Hidenobu Arimoto Yukio Yamada 《International Journal of Heat and Mass Transfer》2009,52(19-20):4221-4228
This paper presents a method of imaging temperature distributions of sub-millimeter-thick water using a near-infrared camera and optical narrow-bandpass filter. The principle is based on the temperature dependence of the ν1 + ν3 absorption band of water. Temperature images are constructed by measuring the absorbance of water at the wavelength of 1412 nm through the filter for all pixels of the camera. From calibration measurements on 0.5-mm thick water at temperatures from 26.0 °C to 40.0 °C, the temperature coefficient was 6.3 × 10?4 K?1 and the standard deviation of absorbance was 1.9 × 10?4. Thermal diffusion in 0.5-mm thick water caused by a thin heating wire was visualized with this method. The obtained images were verified against temperature distributions calculated by solving a two-dimensional thermal conduction model. This method would be useful for temperature measurement applications and control of aqueous solutions in microchips. 相似文献
52.
Ito K Kawase T Sammoto H Gomi K Kariyama M Miyake T 《Journal of Bioscience and Bioengineering》2011,111(3):300-305
Solid-state fermentation (SSF) has attracted a lot of interest for carrying out high-level protein production in filamentous fungi. However, it has problems such as the fermentation heat generated during the culture in addition to the reduced mobility of substances. These conditions lead to a nonuniform state in the culture substrate and result in low reproducibility. We constructed a non-airflow box (NAB) with a moisture permeable fluoropolymer membrane, thereby making it possible to control and maintain uniform and optimal conditions in the substrate. For the NAB culture in Aspergillus oryzae, temperature and water content on/in the whole substrate were more consistent than for a traditional tray box (TB) culture. Total weight after the culture remained constant and dry conditions could be achieved during the culture. These data demonstrate the possibility of growing a uniform culture of the whole substrate for SSF. The NAB is advantageous because it allows for the control of exact temperature and water content in the substrate during the culture by allowing vapor with latent heat to dissipate out of the box. In addition, several enzymes in the NAB culture exhibited higher production levels than in the TB culture. We believe that culturing in the constructed NAB could become a standard technique for commercial SSF. 相似文献
53.
The interaction of the shock reflected at a secondary diaphragm with the primary contact in six cases, i.e. the strengths and shapes of the contact surface are different, were explored by numerical study. The influences of the strength and shape of the contact on the developing wave pattern and the quality of the test gas are illustrated by many kinds of figures (e.g. the time-distance diagrams of the acoustic impedance contours on the axis, the acoustic impedance contours, and the time histories of pilot and static pressures). 相似文献
54.
Computational Visual Media - In this paper we address the problem of geometric multi-model fitting using a few weakly annotated data points, which has been little studied so far. In weak annotating... 相似文献
55.
56.
57.
H Yamauchi H Fukuyama Y Nagahama Y Katsumi Y Dong J Konishi J Kimura 《Canadian Metallurgical Quarterly》1996,53(11):1103-1109
BACKGROUND: The independent influences of small-intestinal bacterial overgrowth and old age on mucosal immunoglobulin production and secretion have not been assessed. This is an important issue, since luminal IgA deficiency may exacerbate small-intestinal bacterial overgrowth, the prevalence of which is high in selected elderly populations. METHODS: Proximal small-intestinal aspirates were obtained from 33 subjects for bacteriologic analysis and measurement of total IgA, IgM, total IgG. IgG subclass, and IgD concentrations. IgA subclasses were measured in 24 unselected subjects. Serum immunoglobulin and salivary IgA concentrations were measured in all subjects. RESULTS: IgA2 and IgG3 were predominant IgA and IgG subclasses in proximal small-intestinal luminal secretions. Luminal concentrations of IgA2 and IgM, but not IgG3 or any other IgG subclass, were significantly increased in small-intestinal bacterial overgrowth, which was present in 19 of 33 (57.6%) subjects. Old age did not influence these levels. Luminal immunoglobulin concentrations did not correlate significantly with either serum or salivary values. IgD was not measureable in proximal small-intestinal secretions. CONCLUSIONS: Increased luminal concentrations of the secretory immunoglobulins, IgA2 and IgM, occur in small-intestinal bacterial overgrowth. Local investigation is mandatory when assessing the mucosal immunopathology of this disorder. Luminal IgG3 is unlikely to be predominantly derived from serum. Old age does not independently influence luminal immunity. 相似文献
58.
Y Takayama M Sugishita T Kido M Ogawa H Fukuyama I Akiguchi 《Canadian Metallurgical Quarterly》1994,57(5):652-654
A right-handed patient with a haematoma in the left pulvinar showed impaired stereoacuity. In contrast with previous reports, he did not show peripheral visual extinction or prolonged reaction times for targets on the side contralateral to the lesion. 相似文献
59.
T Toda S Ikegawa K Okui E Kondo K Saito Y Fukuyama M Yoshioka T Kumagai K Suzumori I Kanazawa 《Canadian Metallurgical Quarterly》1994,55(5):946-950
Fukuyama-type congenital muscular dystrophy (FCMD), the second most common form of childhood muscular dystrophy in Japan, is an autosomal recessive severe muscular dystrophy associated with an anomaly of the brain. After our initial mapping of the FCMD locus to chromosome 9q31-33, we further defined the locus within a region of approximately 5 cM between loci D9S127 and CA246, by homozygosity mapping in patients born to consanguineous marriages and by recombination analyses in other families. We also found evidence for strong linkage disequilibrium between FCMD and a polymorphic microsatellite marker, mfd220, which showed no recombination and a lod score of (Z) 17.49. A "111-bp" allele for the mfd220 locus was observed in 22 (34%) of 64 FCMD chromosomes, but it was present in only 1 of 120 normal chromosomes. This allelic association with FCMD was highly significant (chi 2 = 50.7; P < .0001). Hence, we suspect that the FCMD gene could lie within a few hundred kilobases of the mfd220 locus. 相似文献
60.
This study was designed to examine differences in reaction times of drivers of various age groups and to assess the influence of mental workload on reaction times. Experiments were performed on a simulated street and under other conditions to identify drivers with long reaction times and drivers whose reaction times are affected strongly by mental workloads while driving on a public road. Reaction times after hearing a buzzer were measured under five conditions: (1) sitting in a stationary vehicle, (2) executing mental calculations in a stationary vehicle, (3) driving on a simulated street, (4) executing mental calculations while driving on a simulated street, and (5) driving on a public road. Subjects were 10 drivers each of three age groups. Each experiment was performed by these subjects under the five conditions. Results showed that mental calculations increased the average reaction time for each age group. Mental calculations increased differences among age groups and individuals, and increased differences in respective drivers' individual performance. Mental calculations influenced elderly drivers' reaction times remarkably. Results also demonstrated that an experiment on a simulated street identified drivers who showed long reaction times on a public road. 相似文献