首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   301篇
  免费   6篇
电工技术   1篇
化学工业   31篇
金属工艺   2篇
机械仪表   3篇
建筑科学   15篇
矿业工程   2篇
能源动力   1篇
轻工业   67篇
水利工程   4篇
无线电   15篇
一般工业技术   39篇
冶金工业   75篇
原子能技术   1篇
自动化技术   51篇
  2023年   1篇
  2022年   1篇
  2021年   6篇
  2020年   1篇
  2019年   4篇
  2018年   1篇
  2017年   3篇
  2016年   4篇
  2015年   8篇
  2014年   8篇
  2013年   20篇
  2012年   8篇
  2011年   12篇
  2010年   14篇
  2009年   9篇
  2008年   17篇
  2007年   17篇
  2006年   15篇
  2005年   11篇
  2004年   11篇
  2003年   12篇
  2002年   8篇
  2001年   6篇
  2000年   2篇
  1999年   11篇
  1998年   12篇
  1997年   8篇
  1996年   10篇
  1995年   7篇
  1994年   8篇
  1993年   6篇
  1992年   5篇
  1991年   2篇
  1990年   5篇
  1989年   2篇
  1988年   5篇
  1987年   1篇
  1986年   4篇
  1985年   3篇
  1984年   3篇
  1983年   1篇
  1982年   1篇
  1981年   2篇
  1980年   2篇
  1978年   1篇
  1977年   2篇
  1976年   1篇
  1975年   3篇
  1971年   2篇
  1968年   1篇
排序方式: 共有307条查询结果,搜索用时 31 毫秒
31.
Examined changes in self-concept, perceptions of support from close friends and classmates, and loneliness in 11 8.6–14.6 yr old withdrawn unpopular children with cerebral palsy or spina bifida who had been involved in a social skills training program. The program targeted 5 basic skills: interpersonal problem solving, verbal and nonverbal communication, initiating interactions with peers, conversational skills, and coping with difficult others. To assess the impact of the program, Ss were evaluated before the intervention, after the 10-wk intervention, and at a 6-mo follow-up. Findings indicate that group social skills training may be effective in decreasing feelings of loneliness and increasing perceptions of social acceptance in children who are withdrawn and unpopular at school. Ss' feelings of loneliness were associated with lower ratings of social acceptance and lower ratings of classmate support. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
32.
Interactions between the natural background microflora of shredded lettuce and Listeria innocua (in lieu of Listeria monocytogenes ) were studied. The effect of increasing the initial size of indigenous populations (from 103 to 106–107 CFU g−1) was tested for its ability to reduce L. innocua growth on shredded lettuce. Co-culture experiments were performed in model media, where bacterial isolates from the indigenous microflora were tested for possible inhibitory effects. Varying the size of the indigenous populations had no effect on L. innocua survival or growth. However, interactions with individual species and mixed populations from lettuce did affect the survival and growth of L. innocua in model media. In general, mixed populations diminished L. innocua growth. In the undiluted lettuce medium, the various species tested individually either reduced or did not affect the growth of L. innocua . However, when the medium was diluted, some species extended the survival of L. innocua . Competition between the indigenous microflora and L. innocua resided mostly with the Enterobacter spp. and not with the pseudomonads. Enterobacter cloacae was particularly effective in reducing L. innocua growth. Lactic acid bacteria also reduced L. innocua growth in undiluted media. It is concluded that interactions with the natural background microflora may play an important role in determining the dynamics of Listeria populations on shredded lettuce.  相似文献   
33.
Of 76 clients receiving 8-20 sessions of cognitive therapy (CT) in a joint university and a national health service clinic, 31 experienced sudden gains that appeared very similar to those first reported in clinical trials of CT by T. Z. Tang and R. J. DeRubeis (1999) and subsequently replicated in other studies. The sudden gains appeared less stable in the present study's more routine clinical practice settings than they were in the clinical trials. Life events did not appear to account for sudden gains. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
34.
Clients (N = 77) undergoing cognitive therapy for depression were assessed before treatment with the Clinical Outcomes in Routine Evaluation-Outcome Measure (CORE-OM), which encompasses domains of subjective well-being, problems, functioning, and risk of harming self or others, along with the Beck Depression Inventory-II (BDI-II), the Hamilton Rating Scale for Depression (HRSD), the Beck Hopelessness Scale (BHS), and a measure of avoidant (Cluster C) personality problems (Inventory of Interpersonal Problems-Avoidant [IIP-Av]). The CORE-OM and the BDI-II were strongly correlated with each other and showed coherent and similar patterns of correlations with the HRSD, the BHS, and the IIP-Av. Sixty-one of the clients were repeatedly assessed during treatment with alternating versions of the CORE Short Form and with the BDI-II. Results strongly supported the convergent validity of the CORE measures with the BDI-II in across-clients comparisons of means scores and rates of improvement and in across-sessions comparisons within clients. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
35.
Theories of psychotherapy are implemented by therapists' intentional actions within sessions. This study examined the structure and construct validity of the Therapist Session Intentions (TSI) form. Ten therapists rated their therapeutic intentions following each of 2,305 therapy sessions of cognitive–behavioral or psychodynamic–interpersonal therapy in the Second Sheffield Psychotherapy Project. Seven conceptually coherent clusters of intentions, or therapeutic foci, were identified: treatment context, session structure, affect, obstacles, encouraging change, behavior, and cognition-insight. Contrasting patterns of therapeutic focus across treatments and changes in focus across sessions within treatments appeared conceptually coherent. Correlations across a subsample of sessions confirmed correspondences of the TSI foci with dimensions found previously in observers' ratings. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
36.
The lipid of traditional salted, sun-dried fish is highly susceptible to oxidation during processing and storage at tropical ambient temperatures (25–30°C), leading to browning and potential loss of nutritional and economic value of the product. Determinations of extractable fluorescence and soluble brown colour have been found to be relevant indicators of the high degree of lipid oxidation in such fish. Studies on model systems consisting of aerated fish oil and a range of components natural to fish confirmed that, at 25°C, the products of lipid oxidation reacted with phospholipids and amino acids to produce significant fluorescence. Similarly, proteins and amino acids interacted with lipid oxidation products to produce browning, although at 25°C, this only occurred in the presence of water. Temperatures above 50°C are required for the development of browning of aerated fish oil alone. The level of free amino acids in salted, sun-dried fish was found to decrease during storage which correlates with amino acid involvement in fluorescence and colour production. The fluorescence/colour can be related mechanistically to the development of lipid oxidation products and hence provides a realistic basis for their acting as indicators of extensive lipid oxidation.  相似文献   
37.
The freeze–thaw gelation of hen's egg yolk low density lipoprotein (l.d.l.) has been examined by viscometry, agarose gel filtration, electron spin resonance spectroscopy, electron microscopy and differential scanning calorimetry. The data indicate that the core lipids, the hydrocarbon chains of interfacial lipids of l.d.l. and the sulphydryl, imino, amino and tyrosine groups in the side chains of l.d.l. peptides are not directly involved in the gelation mechanisms. The gelation is caused by non-specific aggregation due to cross-linking of peptides and/or phospholipid polar head groups of adjacent l.d.l. particles. During freezing, interparticle contacts are formed and strengthened as transformation of solvent water into ice increases the concentration of the particles. Salt and sugar additives inhibit large increases in concentrations of l.d.l. during freezing and prevent gelation by helping to increase solvation of interfacial regions of the l.d.l. particles. Agents that induce large viscosity increases in the l.d.l. sols before freezing may act by producing a local conformational change in l.d.l. protein and/or disrupting lipid–protein bonds.  相似文献   
38.
The bitterness and astringency of defined procyanidin fractions from bittersweet English ciders were assessed using a paired-comparison tasting technique. The results demonstrate that, while no one procyanidin can be uniquely identified with bitterness or astringency, bitterness is associated with oligomeric procyanidins reaching a maximum with the epicatechin tetramer whereas astringency is characteristic of higher-molecular-weight procyanidins. The effect of presentation media on taste response was also studied. High sugar and buffer strength suppressed the perceived bitterness, whereas ethanol increased bitterness but simultaneously decreased astringency. It is shown that the observed taste differences between two bittersweet ciders and the taste-modifying effect of ethanol can be explained satisfactorily by current theories of taste.  相似文献   
39.
Near infrared (n.i.r.) reflectance spectroscopy has been employed for the determination of protein, fat and moisture in sliced white bread. N.i.r. reflectance at six wavelengths was measured using circular samples from each of six alternate slices taken from one half of each of 30 loaves of different composition. The six readings for each loaf at each wavelength were averaged and used to produce calibrations which, on prediction of the compositions of a further 30 loaves sampled in the same way, gave rise to standard deviations of differences between n.i.r. and standard procedures of 0.20% for protein, 0.18% for fat and 0.51% for moisture. Calibrations derived from the other halves of the loaves, which had been air-dried and ground to a powder, resulted in similar standard deviation of differences for protein and fat.  相似文献   
40.
In response to J. C. Norcross and J. S. Rossi's (see record 1994-38252-001) comment on our article (D. A. Shapiro et al; see record 1994-38260-001), we note that research as reported does not fully represent the processes whereby it was designed and completed. The true statistical power of an investigation reflects all the analyses carried out, not just those that get reported. The power of our analyses was sufficient to address the substantive questions at issue. The importance of these questions does not depend on allegiance to equivalent outcomes of diverse therapies. The outcome phase of the Second Sheffield Psychotherapy Project is but part of its broad strategic approach to advancing our understanding of the mechanisms of change in the psychotherapies. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号