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192.
Theoretical models of alcohol consumption assert that young adults endorse multiple drinking motives, including drinking to cope with negative experiences and to enhance positive experiences. Social contacts may be important to both pathways. This study applied daily process methodology to determine the relationship between college student drinking in different contexts and daily social contacts and moods. Each afternoon for 3 weeks, 122 undergraduates (43% men, 57% women) logged onto a secure Web site during specified hours to report daily activities, moods, and contacts. Hierarchical linear modeling analyses provided support for motivational models and the context-specific nature of motivated drinking. Individual differences were revealed for each motivation. These findings highlight the importance of studying within-person processes using daily process designs. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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This study was designed to determine the sensitivity and specificity of a reagent-impregnated test strip in identifying habitual snuff users and tobacco chewers. Urine specimens were obtained from smokeless tobacco users and controls and blind tested on-site using a reagent-impregnated test strip. Samples also were sent to our university hospital lab for cotinine and nicotine analysis by gas chromatography (GC). The test strip results were compared with GC results and self-reported use of snuff and chewing tobacco. A total of 61 subjects enrolled in the study: 26 snuff users, 25 tobacco chewers, and 10 nonconsumers of nicotine. Using GC assessment of nicotine and cotinine (>or=200 ng/ml) as the standard, we found the sensitivity of the test strip to be 96% (25/26) for snuff users and 96% (24/25) for tobacco chewers. When compared with self-report, the sensitivity of the test strip was 92.3% (24/26) for snuff users and 84% (21/25) for tobacco chewers. The specificity for nonusers of nicotine was 100% (10/10) for both the self-report and GC conditions. These results suggest that a reagent-impregnated test strip is a rapid, valid, and user-friendly means of differentiating smokeless tobacco users from nonconsumers of tobacco. The intensity of the pink color on the test strip is proportional to the amount of nicotine or its metabolites present in urine and therefore offers a semiquantitative measure of nicotine consumption.  相似文献   
195.
Presents the results of a qualitative study of 4 school psychologists' and 4 teachers' beliefs about causes of student behavior problems and their relation to preferred treatment, teachers' perceived role(s) in consultation, and beliefs about the process and efficacy of consultation. Data were triangulated across 6 sources: 3 interview series with various participants, consultative interactions between the school psychologists and teachers, training sessions during which the school psychologists were trained in consultation, and a consultant questionnaire. Thematic analyses of the data produced 4 themes: (1) impact of causal attributions on beliefs about treatment needed; (2) combination of direct and indirect services; (3) impact of etiological beliefs and academic standards on perceptions of academic success; and (4) support within the consultative relationship. These themes are described and discussed in the context of the dyads studied. Suggestions for future research generated by this study are presented. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
196.
The results of 3 surveys (1 each of federal judges in 1991 and 1998 and another of attorneys in 1999) indicate that practices and beliefs concerning expert testimony have changed in the wake of the 1993 Supreme Court decision on admissibility in Daubert v. Merrell Dow Pharmaceuticals, Inc. Reporting both on their general experience with expert testimony and on their most recent civil trial involving such testimony, judges and attorneys indicated that judges were more likely in 1998 than in 1991 to scrutinize expert testimony before trial and then limit or exclude proffered testimony. The results describe common problems with expert testimony, the characteristics of trials in which expert testimony is introduced, and the types of experts who testify. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
197.
New aromatic molecule–seed particle interactions are examined and exploited to control and guide seed‐mediated gold nanorod (Au NR) growth. This new approach enables better understanding of how small molecules impact the synthesis of metallic nanostructures, catalyzing their use in various biomedical applications, such as plasmonic biosensing. Experimental studies and theoretical molecular simulations using a library of aromatic molecules, making use of the chemical versatility of the molecules with varied spatial arrangements of electron‐donating/withdrawing groups, charge, and Au‐binding propensity, are performed. Au NR growth is regulated by two principal mechanisms, producing either a red or blue shift in the longitudinal localized surface plasmon resonance (LLSPR) peaks. Aromatic molecules with high redox potentials produce an increase in NR aspect ratio and red shift of LLSPR peaks. In contrast, molecules that strongly bind gold surfaces result in blue shifts, demonstrating a strong correlation between their binding energy and blue shifts produced. Through enzymatic conversion of selected molecules, 4‐aminophenylphosphate to 4‐aminophenol, opposing growth mechanisms at opposite extremes of target concentration are obtained, and a chemical pathway for performing plasmonic enzyme‐linked immunosorbent assays is established. This unlocks new strategies for tailoring substrate design and enzymatic mechanisms for controlling plasmonic response to target molecules in biosensing applications.  相似文献   
198.
A structured lipid (SL) with a high amount of sn‐2 palmitic acid was synthesized from anhydrous milkfat and was then enriched with docosahexaenoic (DHA) and arachidonic (ARA) acids using an immobilized lipase. Three different methods were compared including physical blending, enzymatic interesterification, and enzymatic acidolysis. Products were compared with respect to differences in fatty acid profiles, reaction times, antioxidant contents, oxidative stability, melting and crystallization profiles, and reaction yields. The acidolysis method was the least suitable for the synthesis of desired product because of a low reaction yield, low incorporation of DHA, low oxidative stability, and the extra processing steps required. The physical blending and interesterification methods were suitable, but the interesterification product (IE‐SL) had higher amounts of ARA at the sn‐2 position. The IE‐SL contained total ARA and DHA of 0.63 and 0.50 mol%, and 0.55 and 0.46 mol% at the sn‐2 position, respectively. The IE‐SL also contained 44.97 mol% sn‐2 palmitic acid. The reaction yield for the IE‐SL was 91.84 %, and its melting completion and crystallization onset temperatures were 43.1 and 27.1 °C, respectively. This SL might be totally or partially used in commercial fat blends for infant formula.  相似文献   
199.
Each relationship has its own personality. Almost immediately after a social interaction begins, verbal and nonverbal behaviors become synchronized. Even in asocial contexts, individuals tend to produce utterances that match the grammatical structure of sentences they have recently heard or read. Three projects explore language style matching (LSM) in everyday writing tasks and professional writing. LSM is the relative use of 9 function word categories (e.g., articles, personal pronouns) between any 2 texts. In the first project, 2 samples totaling 1,744 college students answered 4 essay questions written in very different styles. Students automatically matched the language style of the target questions. Overall, the LSM metric was internally consistent and reliable across writing tasks. Women, participants of higher socioeconomic status, and students who earned higher test grades matched with targets more than others did. In the second project, 74 participants completed cliffhanger excerpts from popular fiction. Judges' ratings of excerpt–response similarity were related to content matching but not function word matching, as indexed by LSM. Further, participants were not able to intentionally increase style or content matching. In the final project, an archival study tracked the professional writing and personal correspondence of 3 pairs of famous writers across their relationships. Language matching in poetry and letters reflected fluctuations in the relationships of 3 couples: Sigmund Freud and Carl Jung, Elizabeth Barrett and Robert Browning, and Sylvia Plath and Ted Hughes. Implications for using LSM as an implicit marker of social engagement and influence are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
200.
Nature has evolved mechanisms to create a diversity of specialized materials through nanoscale organization. Inspired by nature, hybrid materials are designed with highly tailorable properties, which are achieved through careful control of their nanoscale interactions. These novel materials, based on a silica‐gelatin hybrid system, have the potential to serve as a platform technology for human tissue regeneration. Covalent interactions between the inorganic and organic constituents of the hybrid are essential to enable the precise control of mechanical and dissolution properties. Furthermore, hybrid scaffold porosity is found to highly influence mechanical properties, to the extent where scaffolds of particular strength could be specified based on their porosity. The hybrids also demonstrate a non‐cytotoxic effect when mesenchymal stem cells are cultured on the material. Cytoskeletal proteins of the cells are imaged using actin and vimentin staining. It is envisaged these hybrid materials will find a diverse application in both hard and soft tissue regenerating scaffolds.  相似文献   
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