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101.
102.
Sixteen 1st-generation Asian Indian mothers and fathers were interviewed about the influence of immigration on retention of their own ethnic identity and their ability to promote a sense of ethnic identity in their 2nd-generation children. Data were analyzed with the consensual qualitative research methodology (C. E. Hill et al., 2005) and revealed ethnic identity retention to be influenced by engagement in cultural celebrations and activities, a need to hold onto tradition and upbringing, family ties, social support, and a rejection of perceived Western values. Ethnic identity retention was challenged by environmental obstacles and barriers within American society, loss of familial support, lack of cultural continuity, and an inability to have the "best of both worlds." Furthermore, participants identified specific values and strategies relevant to transmitting an ethnic identity to their children as well as specific challenges to this process, including limited familial and communal guidance and modeling, obstacles from Western culture, an inability to apply their own experience or upbringing, a lack of cultural knowledge, and the potential for intermarriage. Implications of the findings are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
103.
The influence of governance equilibrium on ERP project success   总被引:2,自引:0,他引:2  
As the ERP adopter and ERP consultancy combine their efforts and resources to achieve mutually desirable goals, the problem of governance, which has been mainly identified as an intrafirm problem, is recognized to be an interfirm problem. To investigate the relationship between various governance mechanisms and their capacity to relieve project hazards, we propose a covariance model of ERP governance. The constructed model analyzes the complementary contributions of different governance mechanisms on ERP project success. Four governance mechanisms are studied, including explicit contracts, implicit contracts, reputation, and trust. This study holds that the virtue of one mechanism will grow into the gap of another, forming an equilibrium of governance structure. Then, the governance equilibrium plays a mediating role between ERP project hazards and ERP project success. Empirical analysis based on 122 ERP implementation projects shows a significantly positive relationship between governance equilibrium and ERP project success. Further, in support of transaction cost theory (TCT), the results indicate that governance equilibrium tends to be aligned with exchange hazards, specifically those associated with specialized investments and uncertainty. The empirical evidence suggests that governance equilibrium, when treated as a multidimensional construct, can provide a holistic representation of complex interfirm governance and allow researchers to match broad predictors with broad outcomes, leading to greater explanatory power of governance mechanisms on ERP project success. Implications, limitations, and future research directions of the study are discussed.  相似文献   
104.
Exposure to an acute stressful event enhances trace eyeblink conditioning in male rats, even when rats begin training days after the stressor (Shors, 2001). The authors examined whether the bed nucleus of the stria terminalis (BNST), an area involved in stress and anxiety, is critically involved in this effect and, if so, when. The authors found that excitotoxic lesions to the BNST prevented the enhanced conditioning after stressor exposure. In addition, temporary inactivation of the BNST during the stressor did not alter enhanced responding, whereas inactivation during training prevented the enhancement. These data indicate that stressful experience induces persistent changes in the BNST that are necessary for enhancing learning well after the stressful event has ceased. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
105.
Health benefits of a diet rich in fruits and vegetables are attributed in part to their contents of phenolics and other antioxidant compounds. In this research, the extraction of phenolics and antioxidant compounds from black currant was optimised for different plant organs. The extraction solvent affected yield: aqueous acetone was better than methanol and acetate or glycine buffer. In aqueous buffer, maximum yields of total phenolics and antioxidant activities were obtained at pH 3. Extraction from lyophilised materials yielded extracts with higher phenolic contents and antioxidant activities.  相似文献   
106.
The neuronal mechanism of associative learning and memory storage operating in the central nervous system of the terrestrial mollusc Limax maximus has been modeled as a computer simulation called LIMAX (A. Gelperin et al [1985]). One test of the LIMAX model is to determine whether Limax can learn to avoid a compound stimulus composed of the mixture of two innately attractive odors without simultaneously learning an aversion to the individual odors comprising the mixture. We found that Limax can learn a strong aversion to odor A?+?B while odor A and odor B remain strongly attractive when presented individually. This result led us to reexamine the sensory coding scheme used in the LIMAX model to represent stimulus mixtures, and it suggests neurophysiological experiments to examine the actual chemosensory coding scheme used by Limax. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
107.
The diagnoses of Lyme disease based on clinical manifestations, serological findings and detection of infectious agents often contradict each other. We tested 52 blind-coded serum samples, including 20 pre-treatment and 12 post-treatment sera from clinically suspect Lyme disease patients, for the presence of residual Lyme disease infectious agents, using nested PCR amplification of a signature segment of the borrelial 16S ribosomal RNA gene for detection and direct DNA sequencing of the PCR amplicon for molecular validation. These archived sera were split from the samples drawn for the 2-tier serology tests performed by a CDC-approved laboratory, and are used as reference materials for evaluating new diagnostic reagents. Of the 12 post-treatment serum samples, we found DNA evidence of a novel borrelia of uncertain significance in one, which was also positive for the 2-tier serology test. The rest of the post-treatment sera and all 20 control sera were PCR-negative. Of the 20 pre-treatment sera from clinically suspect early Lyme disease patients, we found Borrelia miyamotoi in one which was 2-tier serology-negative, and a Borrelia burgdorferi in two—one negative and one positive for 2-tier serology. We conclude that a sensitive and reliable DNA-based test is needed to support the diagnosis of Lyme disease and Lyme disease-like borreliosis.  相似文献   
108.
The C1 domain, which represents the recognition motif on protein kinase C for the lipophilic second messenger diacylglycerol and its ultrapotent analogues, the phorbol esters, has emerged as a promising therapeutic target for cancer and other indications. Potential target selectivity is markedly enhanced both because binding reflects ternary complex formation between the ligand, C1 domain, and phospholipid, and because binding drives membrane insertion of the C1 domain, permitting aspects of the C1 domain surface outside the binding site, per se, to influence binding energetics. Here, focusing on charged residues identified in atypical C1 domains which contribute to their loss of ligand binding activity, we showed that increasing charge along the rim of the binding cleft of the protein kinase C δ C1 b domain raises the requirement for anionic phospholipids. Correspondingly, it shifts the selectivity of C1 domain translocation to the plasma membrane, which is more negatively charged than internal membranes. This change in localization is most pronounced in the case of more hydrophilic ligands, which provide weaker membrane stabilization than do the more hydrophobic ligands and thus contributes an element to the structure–activity relations for C1 domain ligands. Coexpressing pairs of C1‐containing constructs with differing charges each expressing a distinct fluorescent tag provided a powerful tool to demonstrate the effect of increasing charge in the C1 domain.  相似文献   
109.
Branched gold nanoparticles with sharp tips are considered excellent candidates for sensing and field enhancement applications. Here, a rapid and simple synthesis strategy is presented that generates highly branched gold nanoparticles with hollow cores and a ca.100% yield through a simple one‐pot seedless reaction at room temperature in the presence of Triton X‐100. It is shown that multibranched hollow gold nanoparticles of tunable dimensions, branch density and branch length can be obtained by adjusting the concentrations of the reactants. Insights into the formation mechanism point toward an aggregative type of growth involving hollow core formation first, and branching thereafter. The pronounced near‐infrared (NIR) plasmon band of the nanoparticles is due to the combined contribution from hollowness and branching, and can be tuned over a wide range (≈700–2000 nm). It is also demonstrated that the high environmental sensitivity of colloidal dispersions based on multibranched hollow gold nanoparticles can be boosted even further by separating the nanoparticles into fractions of given sizes and improved monodispersity by means of a glycerol density gradient. The possibility to obtain highly monodisperse multibranched hollow gold nanoparticles with predictable dimensions (50–300 nm) and branching and, therefore, tailored NIR plasmonic properties, highlights their potential for theranostic applications.  相似文献   
110.
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