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1.
Drawing on developmental contextual theory, the authors examined the relationship of perceived barriers and support with school engagement and vocational attitudes among 9th-grade urban high school students in 2 studies. Study 1 (N=174) showed that both perceived barriers and perceived support from family kin were associated with youths' commitment to school and aspirations for success in their future careers. Study 2 (N=181) replicated and extended Study 1, demonstrating that perceived barriers, general perceptions of support, and kinship support were associated with behavioral and attitudinal indexes of school engagement, as well as with aspirations for career success, expectations for attaining career goals, and the importance of work in one's future. The findings contribute to efforts to identify individual and contextual factors relevant to the educational and vocational lives of urban minority youth. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
2.
We examined the proposition that individual variations in career decision making are related conceptually to the identity formation process of late adolescence. To investigate this proposition 2 studies were conducted to identify the relations between ego identity statuses and decision-making styles. The findings suggested that persons who have achieved a stable identity tend to use rational and systematic decision-making strategies. Those whose identity status is foreclosed tend to rely on dependent strategies and do not endorse systematic and internal strategies. Persons in the diffusion status tend to rely on intuitive and dependent styles or exhibit an absence of systematic and internal styles. The moratorium status was not consistently associated with variations in decision-making styles. We relate the results to previous theory and to implications for practice and research. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
3.
OBJECTIVES: This research studied the relative contribution of diabetes mellitus to the increased prevalence of tuberculosis in Hispanics. METHODS: A case-control study was conducted involving all 5290 discharges from civilian hospitals in California during 1991 who had a diagnosis of tuberculosis, and 37,366 control subjects who had a primary discharge diagnosis of deep venous thrombosis, pulmonary embolism, or acute appendicitis. Risk of tuberculosis was estimated as the odds ratio (OR) across race/ethnicity, with adjustment for other factors. RESULTS: Diabetes mellitus was found to be an independent risk factor for tuberculosis. The association of diabetes and tuberculosis was higher among Hispanics (adjusted OR [ORadj] = 2.95: 95% confidence interval [CI] = 2.61, 3.33) than among non-Hispanic Whites (ORadj = 1.31: 95% CI = 1.19. 1.45): among non-Hispanic Blacks, diabetes was not found to be associated with tuberculosis (ORadj = 0.93: 95% CI = 0.78, 1.09). Among Hispanics aged 25 to 54, the estimated risk of tuberculosis attributable to diabetes (25.2%) was equivalent to that attributable to HIV infection (25.5%). CONCLUSIONS: Diabetes mellitus remains a significant risk factor for tuberculosis in the United States. The association is especially notable in middle-aged Hispanics.  相似文献   
4.
This qualitative study is an exploration of 32 urban high school students’ narratives about the connection between school, work, and societal expectations of their future success related to their racial and ethnic background. The sample varied along 2 contextual dimensions: participation in a psychoeducational intervention (Tools for Tomorrow) and developmental status (i.e., half the sample were 9th-grade students and the other half were 12th-grade students). Using consensual qualitative research, the narratives revealed 3 major domains: future orientation; students’ perceptions of society’s expectations based on race and ethnicity; and students’ perception of the role of their race and ethnicity in future success. Results reveal that the majority of students endorse a connection between school and work, believe that society holds low expectations for them based on their racial and ethnic background, and cannot predict their future success based on their background. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
5.
The inhibitive properties of calcium benzoate for steel corrosion were studied in sodium nitrate solutions at room temperature. Corrosion parameters of the steel/nitrate and steel/benzoate + nitrate interfaces were obtained from polarisation curves. Adsorption parameters of benzoate on steel in sodium nitrate solutions were determined through changes in the degree of surface coverage by the inhibitor, as a function of concentration, time and adsorption potential. The effect of chloride on the corrosion inhibition of benzoate was analysed exposing the metal in different chloride solution concentrations.  相似文献   
6.
Cupric tannate: A low copper content antifouling pigment   总被引:1,自引:0,他引:1  
Fouling organisms attached to man-made surfaces submerged in seawater constitute a major worldwide technical and economical problem. Protection against biofouling is essential for efficient service of boats and ships. Due to recent and imminent restrictions of the use of traditional toxic antifouling paints, there is a growing need for new alternative compounds that ensure a good performance without polluting the marine ecosystem.

The aim of this work is to develop a new antifouling formulation using compounds of natural origin, i.e. tannates, in combination with a minimum concentration of a known bioactive pigment, i.e. copper.

Laboratory assays have shown that cupric tannate has a narcotic effect on biofouling larvae. In the field, after 12 months of immersion in Mar del Plata harbor (Argentine), none of the tested painted panels showed macrofouling organisms. This result was obtained with a large decrease in copper content in the order of 40 times relative to conventional cuprous oxide based paints.

Because copper tannate is not lethal at low concentrations, this pigment has an excellent potential as an antifouling agent.  相似文献   

7.
There have been many methods utilized to fixate the proximal interphalangeal joints of the lesser digits for osseous fusion. The authors present a clinical retrospective review of a new alternative of buried Kirschner wire fixation. A review of forty-six Kirschner wires (30 cases) is presented.  相似文献   
8.
This study presents the educational and career goals and perceptions of supports and barriers related to these goals as described in semistructured interviews of 16 students from diverse racial and ethnic backgrounds attending 9th grade at an urban public high school in a large Northeastern city. Using consensual qualitative research (CQR) methodology (C. E. Hill et al., 2005), the authors identified categories and subcategories to students' perceptions of barriers and supports. The findings highlight students' understanding of how their proximal contexts serve potentially as both supports and barriers. Implications for educational and career interventions are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
9.
The purpose of this investigation was focused on reducing the content of zinc phosphate in anticorrosive paints by means of the incorporation of low quantities of selected soluble corrosion inhibitors. The article describes the anticorrosive behavior of alkyd paints containing reduced levels of zinc phosphate, zinc oxide, and some soluble compounds used as additives (e.g., sodium polyphosphate, sodium phosphate, and sodium benzoate). Anticorrosive solventborne alkyd paints were formulated with a zinc phosphate content of 10% by volume (v/v) with respect to the total pigment concentration. In all cases, the PVC/CPVC (pigment volume concentration/critical pigment volume concentration) ratio was 0.8. Experimental paints, applied on sandblasted SAE 1010 panels, were evaluated by accelerated tests (salt spray cabinet) and electrochemical measurements (electrochemical impedance spectroscopy, EIS). The results show that the additions of small amounts of soluble corrosion inhibitors to low content zinc phosphate paint formulations enhance their performance in a very remarkable way. Perhaps, the most outstanding feature is that the employment of soluble additives allowed the reduction of the zinc phosphate content with concomitant savings.  相似文献   
10.
Tested the hypothesis that the conjoint variance of psychological separation and parental attachment is more strongly related to college student development and adjustment than either set of variables in isolation. Measures of college student development, college student adjustment, psychological separation, and parental attachment were administered to 73 female and 66 male students (mean age 19.1 yrs) attending a large state university in the Northeast. For college student development, there was support for the conjoint hypothesis for the women but not for the men. For college student adjustment, there was no support for the conjoint hypothesis for the women and limited support for the men. The implications of these findings for theory, practice, and future research are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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