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431.
A small library of 2,3‐dihydroxybenzamide‐ and N‐(2,3‐dihydroxyphenyl)‐4‐sulfonamide‐based microsomal prostaglandin E2 synthase‐1 (mPGES‐1) inhibitors was identified following a step‐by‐step optimization of small aromatic fragments selected to interact in focused regions in the active site of mPGES‐1. During the virtual optimization process, the 2,3‐dihydroxybenzamide moiety was first selected as a backbone of the proposed new chemical entities; the identified compounds were then synthesized and biologically evaluated, identifying derivatives with very promising inhibitory activities in the micromolar range. Subsequent structure‐guided replacement of the 2,3‐dihydroxybenzamide by the N‐(2,3‐dihydroxyphenyl)sulfonamide moiety led to the identification of N‐(2,3‐dihydroxyphenyl)‐4‐biphenylsulfonamide ( 6 ), the most potent small molecule of the series (IC50=0.53±0.04 μm ). The simple synthetic procedure and the possibility of enhancing the potency of this class of inhibitors through additional structural modifications pave the way for further development of new molecules with mPGES‐1‐inhibitory activity, with potential application as anti‐inflammatory and anticancer agents.  相似文献   
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434.
Language modeling for large-vocabulary conversational Arabic speech recognition is faced with the problem of the complex morphology of Arabic, which increases the perplexity and out-of-vocabulary rate. This problem is compounded by the enormous dialectal variability and differences between spoken and written language. In this paper, we investigate improvements in Arabic language modeling by developing various morphology-based language models. We present four different approaches to morphology-based language modeling, including a novel technique called factored language models. Experimental results are presented for both rescoring and first-pass recognition experiments.  相似文献   
435.
The nonlinear dynamics of a floating crane is investigated. The motion of the system – consisting of the hull with the crane, the load and a nonlinear mooring system – was found to exhibit various nonlinear phenomena. Operating conditions, in which the motion of the vessel or the load is highly dependent on the initial conditions or disturbances are of special interest. Bifurcations in which a small change of a parameter value causes a large qualitative change of the dynamics often limit the range of save operation.For a floating crane which is periodically forced by waves, different mathematical tools are used to investigate resonances and subharmonic motions. The multiple-scales method allows for the analysis in frequency domain and path following algorithms are applied for a numerical bifurcation analysis. The results of both methods agree very well with each other and both offer tools that could help for the evaluation of operating conditions of crane vessels.  相似文献   
436.
The authors examined the relationship among trauma, coping, depression, and mental health service seeking in a probability sample of sheltered homeless and low-income housed women. Results highlight the diversity of trauma. In a longitudinal analysis, women who lived in shelters or experienced major violence had a twofold increase in their risk of depression over the 6-month follow-up. In a cross-sectional analysis, childhood sexual abuse, living in a shelter, physical violence, childhood physical abuse, and death or injury of a friend or relative predicted avoidant coping and symptoms of depression. Active coping and depression predicted mental health service seeking among traumatized women. Modifying coping strategies may ameliorate some of the negative impact of trauma and potentially enhance mental health service use among at-risk women. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
437.
The purpose of this paper is to provide insight into how companies work during packaging development to reduce negative environmental impact along supply chains, and to compare their practical approaches with the theoretical concepts presented in the literature. The research approach is explorative and based on nine cases in the food and manufacturing industries in Sweden. Data were collected from the managerial perspectives of the packaging manager, the logistics manager and the environmental manager. The findings indicate that companies commonly apply a variety of green packaging approaches with a focus on approaches with clear economic benefits. Moreover, companies seem to lack guidance on how to handle trade‐offs and are unable to fully utilize the theoretical environmental benefits of green packaging approaches because of internal and external barriers. The paper presents five propositions regarding to what extent the theoretical green packaging concepts are applied in practice. To address the gap between theory and practice companies should: develop packaging solutions that contribute to a reduction of environmental impact from the consumer phase (for example through improved apportionment, user‐friendly and informative packaging); use local packaging adaptation as a strategy to address geographically varying transport, handling and waste management conditions; replace brand recognition through packaging size and shape with graphic design, high‐quality materials and printing. The results confirm that internal and external collaborations are important requirements for successful green packaging development. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
438.
It can be expected that many elderly people have impaired opening capacity of food packaging bearing in mind the changes in functionality and physical strength that occur during ageing. This study determined the relation of the quantitative force required to open selected food packaging systems with findings derived from qualitative focus group studies to retrieve comprehensive information on the specific needs of seniors. The focus group studies revealed that the assessment of the ease of opening is very subjective and can vary from objective measurements. The quantitative measurement of the force required to open the ‘easy to open’ thermoformed tray resulted in considerably higher peel initiation forces of 22.50 ± 1.62 N compared to the standard tray (12.80 ± 1.93 N). However, the packaging type was still felt to be easier to open because of the enlarged tab and peeling corner, which was said to be easy to grip. Conversely, the stand‐up pouches with twist‐off caps could only be opened with difficulty because of the small caps and the difficulty in breaking seals, despite the substantially lower opening forces of 0.46 ± 0.06 Nm compared with the other torque closures. The evaluation of a package was found to be only partly dependent on the required opening force but strongly influenced by various design factors and consumer's expectations as well as experiences. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
439.
Here we investigated how a coating of intravascular balloon with paclitaxel (drug-coated balloon; DCB, Freeway?) impacted porcine peripheral artery vascular function and remodeling. Domestic swine (n = 54) underwent percutaneous overstretch balloon dilation of femoral and iliac arteries, controlled by angiography and optical coherence tomography (OCT). Paclitaxel tissue uptake was measured at 1 h and 1, 3, and 9 days post-dilation. At these time-points and at 32 ± 2 days, vascular function of the dilated arteries was assessed using the organ chamber model. Neointimal growth and remodeling indices were determined using OCT and histology at 32 ± 2 days. Intima and media fibrosis were quantified by picrosirius red staining. Post-inflation femoral artery tissue drug levels were 460 ± 214, 136 ± 123, 14 ± 6, and 0.1 ± 0.1 ng/mg at 1 h and 1, 3, and 9 days, respectively. Compared to plain balloon, Freeway? resulted in a significantly smaller neointimal area (P < 0.05), less tunica intima (8.0 ± 5.4 vs 14.2 ± 4.7 %) and media fibrosis (15.6 ± 7.7 vs 24.5 ± 5.4 %), and less femoral artery constrictive remodeling (remodeling index: 1.08 ± 0.08 vs 0.94 ± 0.08). The DCB was associated with significantly increased vasoconstrictor tone and endothelium-dependent vasodilation impairment shortly after post-overstretch injury. Overall, DCB dilation of peripheral arteries resulted in high drug uptake into arterial tissue. Compared with the plain balloon, the DCB was associated with decreased vessel wall fibrosis after balloon overstretch injury, and reduced degrees of constrictive remodeling and neointimal hyperplasia.  相似文献   
440.
Unreinforced masonry (URM) walls show a limited horizontal in‐plane deformation capacity, which can lead to an unfavorable seismic response. To predict this response, the walls' effective stiffness, shear force and drift capacity are required. While mechanics‐based models for the force capacity are well established, such approaches are largely lacking for the effective stiffness and the drift capacity. The mostly empirical code equations for the two latter parameters lead to often unsatisfactory and, in the case of drift capacities, sometimes unconservative predictions when compared to test results. This article summarises recently developed simple closed‐form equations for the effective stiffness, the shear force and the drift capacity. Furthermore, it compares said formulations and currently used code equations to a database of shear compression tests. It shows that the novel models capture the effective stiffness and the drift capacity more accurately than current code equations. The shear force capacity is predicted with a similar reliability, yet using a very simple formulation.  相似文献   
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