全文获取类型
收费全文 | 418篇 |
免费 | 19篇 |
国内免费 | 2篇 |
专业分类
电工技术 | 12篇 |
综合类 | 2篇 |
化学工业 | 44篇 |
金属工艺 | 1篇 |
机械仪表 | 17篇 |
建筑科学 | 30篇 |
能源动力 | 6篇 |
轻工业 | 16篇 |
水利工程 | 3篇 |
石油天然气 | 1篇 |
无线电 | 73篇 |
一般工业技术 | 53篇 |
冶金工业 | 112篇 |
原子能技术 | 1篇 |
自动化技术 | 68篇 |
出版年
2022年 | 4篇 |
2021年 | 3篇 |
2020年 | 4篇 |
2018年 | 11篇 |
2017年 | 4篇 |
2016年 | 4篇 |
2015年 | 12篇 |
2014年 | 6篇 |
2013年 | 21篇 |
2012年 | 18篇 |
2011年 | 15篇 |
2010年 | 17篇 |
2009年 | 15篇 |
2008年 | 22篇 |
2007年 | 18篇 |
2006年 | 18篇 |
2005年 | 10篇 |
2004年 | 12篇 |
2003年 | 13篇 |
2002年 | 7篇 |
2001年 | 9篇 |
2000年 | 16篇 |
1999年 | 18篇 |
1998年 | 42篇 |
1997年 | 19篇 |
1996年 | 28篇 |
1995年 | 10篇 |
1994年 | 8篇 |
1993年 | 4篇 |
1991年 | 4篇 |
1990年 | 9篇 |
1989年 | 2篇 |
1988年 | 2篇 |
1987年 | 1篇 |
1986年 | 1篇 |
1985年 | 6篇 |
1984年 | 1篇 |
1983年 | 1篇 |
1982年 | 4篇 |
1981年 | 2篇 |
1980年 | 1篇 |
1979年 | 1篇 |
1978年 | 2篇 |
1977年 | 2篇 |
1976年 | 4篇 |
1975年 | 2篇 |
1974年 | 1篇 |
1973年 | 1篇 |
1972年 | 2篇 |
1959年 | 1篇 |
排序方式: 共有439条查询结果,搜索用时 46 毫秒
391.
Ho Samuel M. Y.; Kwong-Lo Rosalie S. Y.; Mak Christine W. Y.; Wong Joe S. 《Canadian Metallurgical Quarterly》2005,73(2):344
In this study, the authors examined fear related to severe acute respiratory syndrome (SARS) among 2 samples of hospital staff in Hong Kong. Sample 1 included health care workers (n = 82) and was assessed during the peak of the SARS epidemic. Sample 2 included hospital staff who recovered from SARS (n = 97). The results show that participants in both samples had equal, if not more, concern about infecting others (especially family members) than being self-infected. Sample 1 participants had stronger fear related to infection than Sample 2 participants, who seemed to be concerned more about other health problems and discrimination. Participants with lower self-efficacy tended to have higher fear related to SARS. Fear related to SARS was also correlated positively with posttraumatic stress symptoms among respondents of Sample 2 (recovered staff). Interventions based on these findings are described. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
392.
C.Y. Mak 《Chemical engineering science》2006,61(19):6261-6272
Measurements and observations of the phase split occurring at a small diameter vertical T-junction are reported. Time varying, void fraction data obtained using ring-type conductance probes have been analysed to yield valuable information regarding the effect of the junction on flow behaviour. It is shown through comparisons with the work of Stacey et al. [2000. The split of annular two-phase flow at a small diameter T-junction. International Journal of Multiphase Flow 26, 845-856] in a horizontal T-junction of a similar size that the orientation of the junction has no influence on the flow split. This behaviour is attributed to the absence of flooding and is corroborated by our high-speed images. Subsequently, better prediction of the phase split is obtained when the model of Azzopardi [1988. Measurements and observations of the split of annular flow at a vertical T-junction. International Journal of Multiphase Flow 14, 701-710] is modified to account for the absence of flooding. Regarding flow transitions, the methods by Barnea et al. [1983. Flow pattern in horizontal and vertical two-phase flow in small diameter pipes. The Canadian Journal of Chemical Engineering 61, 617-620] and Omebere-Iyari et al. [2005. Flow patterns for gas/liquid flow in small diameter tubes. Ninth UK National Heat Transfer Conference, Manchester, UK, 5-6 September] are found to give good predictions of the exit flow patterns in the horizontal side arm and vertical run arm, respectively. 相似文献
393.
S.M. Mak B.T. Tey K.Y. Cheah W.L. Siew K.K. Tan 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2009,84(9):1405-1411
BACKGROUND: Palm kernel shell activated carbon (OPSA) produced by steam gasification at high temperatures generally results in high surface areas of 1146 to 1600 m2 g?1, attributed to the high volume of micropores (0.43 to 0.56 cm3 g?1). The mesoporosity of naturally occurring activated carbons is observed to increase with decreasing particle size. Mechanical grinding was therefore performed to investigate its effect on the mesoporosity and microporosity of OPSA. RESULTS: Mechanical grinding had a strong effect on mesopore volume and average pore diameter, with an increase in mesopore volume from 47 to 66% as particle size decreases. Interestingly, no significant effect on the micropore fraction was observed in ground OPSA particles. CONCLUSIONS: The mechanically ground OPSA particles possessed dual adsorption capabilities due to the high microporosity and moderate mesoporosity contained in the structures. This results in interesting porosity behaviour of palm kernel shell activated carbons and the potential to provide materials of distinct sorption capacities with minimal treatment. Copyright © 2009 Society of Chemical Industry 相似文献
394.
B. Mak 《Journal of Computer Assisted Learning》2001,17(1):94-103
Abstract This paper surveys the attitudes on the use of computers for aesthetic communication. In spite of the proliferation of computer art software and the popularity of art galleries on the world-wide web, many artists still find it difficult to accept computer art as a form of art. Many of them find only commercial values in computer art. To understand the latent attitudes constituting this rejection, a survey was conducted among high school students and the data was analysed with LISREL structural equation modelling techniques. Results indicate that aesthetic concerns, conservatism, and stereotypes are the major factors accounting for the negative attitude. Implications for system design to overcome the negative attitudes are discussed. 相似文献
395.
Mak C.L. Luk K.M. Lee K.F. Chow Y.L. 《Antennas and Propagation, IEEE Transactions on》2000,48(5):777-783
The L-shaped probe is shown to be an attractive feed for the thick microstrip antenna (thickness around 10% of the operating wavelength). A parametric study on the rectangular patch antenna is presented. It is found that the antenna attains 36% impedance bandwidth (SWR⩽2) as well as gain bandwidth and about 7-dBi average gain. A two-element array fed by L-probes is also proposed. Experiments show that the array design can substantially suppress the cross polarization of the proposed antenna. Both the antennas have stable radiation patterns across the passband. Moreover, the measured resonant frequencies of the proposed antenna agree well with an existing formula and the L-probe does not have much effect on the resonant frequency 相似文献
396.
Peizhi Xu Hin‐yu Mak Tao Du Vladimir G. Chigrinov Hoi‐sing Kwok 《Journal of the Society for Information Display》2008,16(11):1157-1164
Abstract— In this paper, many popular methods to study transflective liquid‐crystal‐displays (LCDs) have been discussed, and several new transflective LCD configurations with a single‐cell gap have been proposed. The traditional double‐cell‐gap method gives the best match of the transmittance/reflectance voltage curve (TVC/RVC) and also the widest viewing angle, but also brings the highest fabrication complexity. The single‐cell‐gap transflective LCD is much easier to fabricate and also shows a good match of TVC/RVC. A new methodology has been shown to find optimal configurations for single‐cell‐gap transflective LCDs. New configurations using multimode in a single pixel include twisted nematic (TN) optically compensated bend (OCB), TN electrically controlled birefringence (ECB), and TN low‐twisted nematic (LTN). TN and hybrid‐aligned nematic (HAN) modes have been investigated for single‐mode transflective LCDs. The results exhibit high contrast ratio, a good match of TVC/RVC, as well as wide viewing angle. 相似文献
397.
G.Q. Huang B. Shen K.L. Mak 《The International Journal of Advanced Manufacturing Technology》2001,17(10):775-782
There has been widespread interest in the development and application of the World Wide Web (WWW) to support decision-making
activities in product design and manufacture. An increasing number of web applications are emerging and a large number of
practitioners are trying these web-based decision support systems. In the meantime, it becomes increasingly difficult to surf
for appropriate web applications on the Internet using general-purpose search engines. This paper describes a web site, WAPIP,
that has been developed specifically to support new product introduction activities. It provides databases for software vendors
and researchers to register their web applications with the WAPIP search engine. It also provides facilities to support practitioners
in product design and manufacture to search rapidly for the web applications that are suitable for solving their problems.
This paper discusses the various issues regarding the design, development and operation of this WAPIP search engine. 相似文献
398.
G. Q. Huang S. W. Lee K. L. Mak 《The International Journal of Advanced Manufacturing Technology》2001,18(8):605-613
Product development continues to be at the core of manufacturing industries and the heartland of global competition in the
21st century. The e-commerce technologies will have a profound impact on the practice and performance of product development.
This paper examines the roles of web applications in collaborative product design and manufacture. The emphasis is placed
not only upon the geographical and disciplinary dimensions, but also on the time dimension of collaboration. A case study
is used to demonstrate how synchronised web applications can be used to facilitate collaborative product definition. The project
team members share the common work-space that maintains the integrity and consistency of product and process information. 相似文献
399.
David T. Yew Lai-Yin Yeung Maria Sen-Mun Wai Ying T. Mak 《Microscopy research and technique》2009,72(9):684-689
This study evaluated the 5-HT1A and 5-HT2A receptor positive cells in the cerebella of mice and human by immunocytochemistry. Mice were of ages 1, 3, and 12 months whereas the human subjects were divided into two groups, a younger 57–78 years old group and an older 82–91 years old group. Both 5-HT1A and 5-HT2A receptor positive cells were observed in the molecular and granular layers of the cerebella of mice and human. Although there was a decline in these positive cells during aging, no regional difference in the positive cells were observed in the anterior, middle, and posterior regions of the cerebella. Microsc. Res. Tech. 2009. © 2009 Wiley-Liss, Inc. 相似文献
400.
A small circularly polarised (CP) patch antenna with dual T-shaped probe feeds is presented. The patch is folded like a cap to generate a CP wave as well as to reduce the size of the antenna. The proposed antenna is operated at the centre frequency of 2.28 GHz with circular polarisation. The impedance bandwidth (SWR<2) is 21.8% from 2 to 2.49 GHz and the axial ratio bandwidth (AR<3 dB) is 3.5%. The measured gain is around 7.5 dBi. The antenna shows a good CP performance with a symmetric radiation pattern. The total area of reduction is 54% in comparison with the conventional half-wave patch antenna. 相似文献