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121.
122.
Walden Brent; McGue Matt; lacono William G.; Burt S. Alexandra; Elkins Irene 《Canadian Metallurgical Quarterly》2004,113(3):440
Although behavior genetic studies have suggested that early substance use is primarily environmentally mediated, no study has sought to identify the specific sources of environmental variance. Using data obtained from multiple informants, this study assessed the contributions of peer deviance and parent-child relationship problems to substance use in 14-year-old male and female twins (N = 1,403) drawn from the Minnesota Twin Family Study (MTFS). All three phenotypes were influenced primarily by shared environmental variance (average c2 = .51), as was the overlap among them. Moreover, peer deviance and parent-child relationship problems accounted for approximately 77% of the variance in early substance use. Findings also indicated that peer deviance, but not parent-child relationship problems, accounted uniquely for variance in early substance use. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
123.
Familial Dysautonomia (FD) is an autosomal recessive disease of unknown etiology, occurring primarily in Ashkenazi Jews. Patients
are neurologically impaired, with deficits primarily in autonomic and sensory functions. The biochemical and genetic defects
have remained elusive, precluding carrier detection and prenatal diagnosis. High-performance liquid chromatography data indicated
up to a threefold increase in the neutral glycosphingolipid globotriaosylceramide in Dysautonomic fibroblasts and lymphoblasts.
Total ganglioside values, measured by colorimetric, fluorometric or specific sodium borohydride incorporation, were decreased.
Affected fibroblasts exhibited a range of pleomorphic phenotypes, such that the usual swirl-like confluent growth pattern
of normal fibroblasts was distorted to varying degrees, suggesting abnormalities in the FD plasma membrane, possibly affecting
cell-cell contacts. The glycosphingolipid increase could not be accounted for on the basis of markedly decreased α-galactosidase
activity, as in Fabry's disease, where patients also display decreased autonomic function. 相似文献
124.
Kim Irene J.; Ge Xiaojia; Brody Gene H.; Conger Rand D.; Gibbons Frederick X.; Simons Ronald L. 《Canadian Metallurgical Quarterly》2003,17(4):571
The occurrence and co-occurrence of depressive symptoms and conduct problems were examined in the context of parenting behaviors in a community-based sample of 897 African American children and their primary caregivers using a multi-informant, longitudinal design. Parenting behaviors and clinical symptoms were assessed in 2 waves, when the children averaged 10.5 and 12.3 years of age. Parenting behaviors differed significantly according to a child's symptomatology; (a) that is, when a child exhibited no depressive or conduct problems, (b) depressive problems only, (c) conduct problems only, or (d) co-occurring depressive and conduct problems. When parenting behaviors were examined according to changes in children's symptom levels, children whose symptoms increased over time reported increases in hostility and harsh-inconsistent parenting and decreases in warmth and nurturant-involved parenting. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
125.
José A. Carrillo Irene M. Gamba Armando Majorana Chi-Wang Shu 《Journal of Computational Electronics》2003,2(2-4):375-380
We present preliminary results of a high order WENO scheme applied to deterministic computations for two dimensional formulation of the transients for the Boltzmann-Poisson system describing electron transport in semiconductor devices. The collisional term models optical-phonon interactions which become dominant under strong energetic conditions corresponding to nanoscale active regions under applied bias. We treat the Boltzmann Transport equation in a spherical coordinate system for the wave-vector space. The problem is three dimensional in the wave-vector space and two dimensional in the physical space, plus the time variable driving to steady states. The new formulation avoids the singularity due to the spherical coordinate system. 相似文献
126.
This article's major objective is to effectively prepare the graduate student in psychology for the internship application process by providing critical and relevant information. Preparation begins early on in one's graduate career and usually involves the following steps: (a) establishing mentoring relationships, (b) preparing an application portfolio, (c) collecting information, (d) applying, (e) interviewing, (f ) ranking the selected agencies, and (g) responding on selection day. Information is also provided on how to use the Association of Psychology Postdoctoral Internship Centers (APPIC) Clearinghouse. Finally, a brief section is devoted to the process of choosing a non-APPIC site. Advance preparation can make this entire process easier and increase a student's chance of finding a suitable predoctoral internship in psychology. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
127.
Pepperberg Irene M.; Garcia Sean E.; Jackson Eric C.; Marconi Sharon 《Canadian Metallurgical Quarterly》1995,109(2):182
Two Grey parrots (Psittacus erithacus) were tested on various types of mirror use: mirror image stimulation, mirror-mediated object discrimination, and a simple form of mirror-mediated spatial locating. During exposure to a mirror, neither bird clearly demonstrated self-exploratory behavior but responded instead in ways similar to those of marmosets, monkeys, dolphins, extremely young children ( 相似文献
128.
Ge Xiaojia; Kim Irene J.; Brody Gene H.; Conger Rand D.; Simons Ronald L.; Gibbons Frederick X.; Cutrona Carolyn E. 《Canadian Metallurgical Quarterly》2003,39(3):430
Effects of early physical maturation and accelerated pubertal changes on symptoms of major depression were examined in 639 African American children. Three rival hypotheses, early timing, off-time, and stressful change, were tested using 2 waves of data (mean ages = 11 and 13 years). The pubertal effect operates differently according to children's gender and age. For girls, early maturation was consistently associated with elevated levels of depressive symptoms. For boys, early maturers manifested elevated levels of depression only at age 11, but these symptoms subsided by age 13. Boys who experienced accelerated pubertal growth over time displayed elevated symptom levels. Results support the early timing hypothesis for girls and the stressful change hypothesis for boys. Time at assessment is critical when examining boys' pubertal transition. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
129.
Metallic aluminium was anodically dissolved in an organic electrolyte. A viscous solution, containing a polyiminoalane precursor was obtained. Nicalon (SiC) fibres were thermally pretreated and then coated with this fluid. The coated fibres were dried and calcined at 900 ° C in anhydrous ammonia. Thermal pretreatment of the fibres in nitrogen at 1400 ° C and dip coating with solutions of relatively low aluminium concentrations resulted in dense, nearly uncracked aluminium nitride layers. 相似文献
130.
New institutions are coming to the fore as stakeholders in research, particularly hospitals and clinical departments involved in providing health care. As a result, new environments for research are gaining importance. This study aims to investigate how different individual characteristics, together with collective and contextual factors, affect the activity and performance of researchers in the particular setting of hospitals and research centres affiliated with the Spanish National Health System (NHS). We used a combination of quantitative science indicators and perception-based data obtained through a survey of researchers working at NHS hospitals and research centres. Inbreeding and involvement in clinical research is the combination of factors with the greatest influence on scientific productivity, because these factors are associated with increased scientific output both overall as well as in high-impact journals. Ultimately, however, satisfaction with human resources in research group combined with gender (linked in turn to leadership) is the combination of factors associated most clearly with the most relevant indicator of productivity success, i.e. the number of articles in high-impact journals as principal author. Researchers’ competitiveness in obtaining research funding as principal investigator is associated with a combination of satisfaction with research autonomy and involvement in clinical research. Researchers’ success is not significantly related with their age, seniority and international experience. The way health care institutions manage and combine the factors likely to influence research may be critical for the development and maintenance of research-conducive environments, and ultimately for the success of research carried out in hospitals and other settings within the national public health system. 相似文献