全文获取类型
收费全文 | 263篇 |
免费 | 9篇 |
专业分类
电工技术 | 5篇 |
化学工业 | 46篇 |
金属工艺 | 5篇 |
机械仪表 | 1篇 |
建筑科学 | 17篇 |
矿业工程 | 1篇 |
能源动力 | 4篇 |
轻工业 | 24篇 |
水利工程 | 15篇 |
石油天然气 | 1篇 |
无线电 | 6篇 |
一般工业技术 | 23篇 |
冶金工业 | 96篇 |
原子能技术 | 1篇 |
自动化技术 | 27篇 |
出版年
2024年 | 2篇 |
2022年 | 7篇 |
2021年 | 5篇 |
2020年 | 1篇 |
2019年 | 12篇 |
2018年 | 6篇 |
2017年 | 2篇 |
2016年 | 1篇 |
2015年 | 5篇 |
2014年 | 10篇 |
2013年 | 6篇 |
2012年 | 8篇 |
2011年 | 15篇 |
2010年 | 16篇 |
2009年 | 4篇 |
2008年 | 17篇 |
2007年 | 15篇 |
2006年 | 10篇 |
2005年 | 10篇 |
2004年 | 11篇 |
2003年 | 12篇 |
2002年 | 9篇 |
2001年 | 8篇 |
2000年 | 10篇 |
1999年 | 1篇 |
1998年 | 5篇 |
1997年 | 8篇 |
1996年 | 4篇 |
1995年 | 4篇 |
1994年 | 6篇 |
1993年 | 4篇 |
1992年 | 2篇 |
1990年 | 1篇 |
1989年 | 5篇 |
1988年 | 1篇 |
1987年 | 1篇 |
1986年 | 5篇 |
1985年 | 1篇 |
1984年 | 7篇 |
1983年 | 1篇 |
1982年 | 3篇 |
1981年 | 3篇 |
1980年 | 2篇 |
1979年 | 1篇 |
1978年 | 2篇 |
1977年 | 1篇 |
1976年 | 1篇 |
1973年 | 1篇 |
排序方式: 共有272条查询结果,搜索用时 15 毫秒
21.
The authors propose that the costs and benefits of directed forgetting in the list method result from an internal context change that occurs between the presentations of 2 lists in response to a "forget" instruction. In Experiment 1 of this study, costs and benefits akin to those found in directed forgetting were obtained in the absence of a forget instruction by a direct manipulation of cognitive context change. Experiment 2 of this study replicated those findings using a different cognitive context manipulation and investigated the effects of context reinstatement at the time of recall. Context reinstatement reduced the memorial costs and benefits of context change in the condition where context had been manipulated and in the standard forget condition. The results are consistent with a context change account of directed forgetting. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
22.
Current wrought magnesium alloys: Strengths and weaknesses 总被引:9,自引:0,他引:9
Colleen Bettles Mark Gibson 《JOM Journal of the Minerals, Metals and Materials Society》2005,57(5):46-49
The opportunities for extruded and sheet magnesium products in the automotive industry, in particular, are increasing as the
quest for lightweighting gains momentum. However, the current alloys all have limitations and these are accentuated when higher
productivity targets are also imposed. This article attempts to summarize the strengths and weaknesses of the current wrought
alloys, with particular emphasis on the extrusion process, and also considers alternative processing routes which may be useful
in overcoming some of these shortcomings.
For more information, contact Colleen Bettles, CMIT Private Bag 33, Clayton South MDC, Clayton Victoria 3169, Australia; +61-3-95452936;
fax +61-3-95441128; e-mail Colleen.Bettles@csiro.au. 相似文献
23.
Colleen Wade Michael Spearpoint Charles Fleischmann Greg Baker Anthony Abu 《Fire Technology》2018,54(4):893-920
There is an increasing desire to use more engineered timber products in buildings, due to the perceived aesthetics of timber and desire for more sustainable architecture. However, there are concerns about fire performance of these products especially in taller buildings. This has led to renewed research to understand the behaviour of timber surfaces in compartments exposed to fire. This paper describes a two-zone calculation model for determining the fire environment within a compartment constructed from timber products where varying amounts of timber are exposed on the walls and ceiling. A set of eight full-scale compartment experiments previously reported in the literature are used to assess the capability of the model. The fire load energy density in the experiments ranged from 92 MJ/m2 to 366 MJ/m2 comprising either wood cribs or bedroom furniture with the largest compartment having dimensions 4.5?×?3.5?×?2.5 m high with an opening 1.069 m wide?×?2.0 m high. The experiments were ventilation-controlled. It is shown that the model can be used to provide conservative predictions of the fire temperatures for compartments with timber exposed on the walls and/or ceiling as part of an engineering analysis. There are several limitations that are discussed including the need to consider the debonding of layers in the case of cross-laminated timber. It is recommended that further benchmarking of the model be done for different ventilation conditions and with engineered timber products where debonding does not occur. This will test the model under a wider range of conditions than examined in this paper. 相似文献
24.
The aim of this research was to exploit the chemical properties of natural products to control the incidence and extent of mould growth in houses. The screening of antimould activities of seven essential oil extracts showed that most of the extracts completely inhibited the growth of all three test mould at the concentration of 1% w/v on nutrient medium, whereas, different fractions of manuka oil showed varied activity. Subsequently, using both mycological and scanning electron microscopy, the testing of selected extracts on two different types of gypsum board finished with either paint or wall-paper, confirmed the antimould activity of eugenol, thymol and cinnamaldehyde against Penicillium corylophilum. This study identified certain essential oil extract as a potential mould inhibitor for panel products which is one of the most common mould habitats in the building environment. Mould growth in residential houses is a major concern and chemical fungicides commonly used to control the growth of mould are not often appropriate for indoor applications. Natural alternatives such as essential oils are desirable for this application. Knowledge gained through this research should lead to new niche panel product development to create healthier housing. 相似文献
25.
Reduced protein quality is one of the concerns currently confronting the supply and utilization of wheat distillers dried grain with solubles (DDGS) as an animal feed ingredient. This study assessed the protein quality of wheat DDGS, expressed as acid detergent insoluble crude protein (ADICP) and lysine content, by blending wet distillers grain (WDG) with varying condensed distillers solubles (CDS) levels and drying using forced air convection, microwave, and microwave–convection methods. As the CDS level was increased, the protein content of wheat DDGS generated from the three drying methods increased. Interactions of CDS level with drying air temperature, microwave power, and microwave–convection settings had a significant effect (p < 0.05) on average ADICP and lysine contents. Higher ADICP and lower lysine contents were observed in samples dried at higher temperature, microwave power, and microwave convection settings. Further, the CDS level significantly affected the color parameters of microwave- and microwave–convection-dried samples and the drying air temperature–CDS level interaction significantly affected the color of forced air convection–dried samples. Significant lysine content–redness, ADICP–lightness color parameter, and ADICP–total color difference correlations were found in forced air convection–, microwave-, and microwave–convection-dried samples, respectively. Microwave and microwave–convection drying achieved desirable protein quality associated with low-temperature drying at much shorter times. 相似文献
26.
Cochran Susan D.; Keenan Colleen; Schober Christine; Mays Vickie M. 《Canadian Metallurgical Quarterly》2000,68(6):1062
Concerns about dysfunctional alcohol use among lesbians and gay men are longstanding. The authors examined alcohol use patterns and treatment utilization among adults interviewed in the 1996 National Household Survey on Drug Abuse. Sexually active respondents were classified into 2 groups: those with at least 1 same-gender sexual partner (n?=?194) in the year prior to interview and those with only opposite-gender sexual partners (n?=?9,714). The authors compared these 2 groups separately by gender. For men, normative alcohol use patterns or morbidity did not differ significantly between the 2 groups. However, homosexually active women reported using alcohol more frequently and in greater amounts and experienced greater alcohol-related morbidity than exclusively heterosexually active women. Findings suggest higher risk for alcohol-related problems among lesbians as compared with other women, perhaps because of a more common pattern of moderate alcohol consumption. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
27.
Xunli Zhang Colleen S. -M. Lee D. Michael P. Mingos David O. Hayward 《Applied Catalysis A: General》2003,240(1-2):183-197
Oscillatory reactions over palladium foil and wire catalysts during the oxidation of methane have been investigated over a wide range of reaction temperatures and argon/methane/oxygen feed gas compositions. Characterisation of the catalyst has also been carried out using scanning electron microscopy (SEM) techniques, which revealed the presence of a porous surface. This suggested that the metal surface has undergone a change since the reaction commenced, and using X-ray powder diffraction (XRD) techniques the palladium phase was shown to be the dominant phase present. Hysteresis phenomena were observed in the activity of the reaction as the temperature was cycled up and down, showing that the metal surface was continually changing throughout the reaction. The activation energies of the reaction during the high reactivity mode, PdO, and low reactivity mode, Pd, were also calculated. Oscillation rates were observed to depend on the dominant surface. Oscillations were frequent when the high reactivity mode was dominant while the activation energy of this mode was found to be low. When the low reactivity mode was dominant, the oscillations were slower and the activation energy was three times larger. The results obtained imply that the behaviour of the palladium surface, switching back and forth from the reduced state to the oxidised state, is responsible for the oscillatory behaviour seen in this system. 相似文献
28.
There is evidence that Japanese macaques (Macaca fuscata) are extremely sensitive to dynamic changes in the relative amplitudes of coo call harmonics during discrimination tests. To verify this evidence using more controlled stimulus configurations, the authors examined threshold sensitivity of macaque monkeys to amplitude increments added to the standard level of coo call harmonics. Psychophysical threshold determination methods paralleled those used previously to determine macaque sensitivity to amplitude increments added to vowel-like stimuli. Variation was detectable although thresholds were elevated relative to those obtained with vowel-like stimuli in another investigation (C. G. Le Prell, A. J. Niemiec, & D. B. Moody, 2001). This elevation was probably a function of natural amplitude modulation in the standard stimuli. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
29.
Argues that any test of a model of human judgment must consider the possibility that the psychophysical functions for the stimulus variables are not the identity function and that rating scale responses are not a linear function of the S's impression. It is maintained that in their research on covariation judgment, D. M. Lane et al (1985) did not consider either of these possibilities. (10 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
30.
Karuza Jurgis; Zevon Michael A.; Gleason Timothy A.; Karuza Colleen M.; Nash Linda 《Canadian Metallurgical Quarterly》1990,5(2):194
The analysis of P. Brickman et al (see record 1982-30315-001), which separates attribution of a problem's cause and solution, was tested in 4 studies. Young and elderly adults' (n?=?210) well-being was related only to taking responsibility for solutions. The elderly compared with the young adults assumed less responsibility for problem cause and solution. They also preferred helping and coping models that assume low self-responsibility for solutions (e.g., medical model). This result was replicated with Meals on Wheels clients (n?=?51). An intragenerational helping pattern was found in Study 3. Lay helpers (n?=?63) helped mainly same-age recipients. Elderly and middle-aged helpers compared with young adults preferred using a medical model. Overall, a cohort bias in model preference was suggested. In Study 4, problem type and recipient age moderated attributions and model choice of young and middle-aged Ss (n?=?92). Relevance to the control literature and ethical and clinical implications of a medical-model bias are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献