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One of the main challenges that organizations face nowadays, is the efficient use of individual employee intelligence, through machine-facilitated understanding of the collected corporate knowledge, to develop their collective intelligence. Web 2.0 technologies, like wikis, can be used to address the above issue. Nevertheless, their application in corporate environments is limited, mainly due to their inability to ensure knowledge creation and assessment in a timely and reliable manner. In this study we propose CorpWiki, a self-regulating wiki system for effective acquisition of high-quality knowledge content. Inserted articles undergo a quality assessment control by a large number of corporate peer employees. In case the quality is inadequate, CorpWiki uses a novel expert peer matching algorithm (EPM), based on feed-forward neural networks, that searches the human network of the organization to select the most appropriate peer employee who will improve the quality of the article. Performance evaluation results, obtained through simulation modeling, indicate that CorpWiki improves the final quality levels of the inserted articles as well as the time and effort required to reach them. The proposed system, combining machine-learning intelligence with the individual intelligence of peer employees, aims to create new inferences regarding corporate issues, thus promoting the collective organizational intelligence.  相似文献   
104.
Cordierite monoliths, ceramic foams made from mullite and zirconia–alumina as well as γ-Al2O3 pellets were employed as supports for Ni/La2O3 structured catalysts for the production of hydrogen by catalytic partial oxidation of ethanol. Although all catalysts were very active for ethanol conversion and very selective towards the desired products, the one supported on the zirconia–alumina ceramic foam produced slightly better results. Tested under a wide variety of process conditions, the catalyst supported on the monolith exhibited excellent catalytic performance and long-term stability. In addition to this catalyst, which was prepared by washcoating the active phase on the support, catalysts were prepared on monoliths by adsorption and sol–gel techniques. Adsorption from solutions produced the catalyst with the weakest performance while the sol–gel method resulted in a catalyst with intriguing behavior. Overall, catalysts produced by washcoating on cordierite monoliths are the most promising candidates for the production of hydrogen by partial oxidation of ethanol. Other supports and preparation methods have the potential to produce better catalytic materials but require further optimization.  相似文献   
105.
Characteristics of inert starters in drug solution layering are important for successful active pellet formation. Four types of starters composed of sucrose or microcrystalline cellulose (MCC) or lactose and MCC were compared in our study. The active pellets were prepared using Wurster type apparatus. Yield and pellet quality parameters were determined. The highest yield (85.66-89.41%) was obtained for cores composed of MCC due to their insolubility in water (the drug solvent) and good mechanical properties. On the contrary, soluble and brittle sucrose cores dissolved partially during the process forming undesirable agglomerates and giving lower yield (76.2%). All pellet samples showed good flow properties and drug content from 82.4 to 94.5% of the theoretical drug amount.  相似文献   
106.
Pancreatic cancer is a unique cancer in that up to 90% of its tumour mass is composed of a hypovascular and fibrotic stroma. This makes it extremely difficult for chemotherapies to be delivered into the core of the cancer mass. We tissue-engineered a biomimetic 3D pancreatic cancer (“tumouroid”) model comprised of a central artificial cancer mass (ACM), containing MIA Paca-2 cells, surrounded by a fibrotic stromal compartment. This stromal compartment had a higher concentration of collagen type I, fibronectin, laminin, and hyaluronic acid (HA) than the ACM. The incorporation of HA was validated with alcian blue staining. Response to paclitaxel was determined in 2D MIA Paca-2 cell cultures, the ACMs alone, and in simple and complex tumouroids, in order to demonstrate drug sensitivity within pancreatic tumouroids of increasing complexity. The results showed that MIA Paca-2 cells grew into the complex stroma and invaded as cell clusters with a maximum distance of 363.7 µm by day 21. In terms of drug response, the IC50 for paclitaxel for MIA Paca-2 cells increased from 0.819 nM in 2D to 3.02 nM in ACMs and to 5.87 nM and 3.803 nM in simple and complex tumouroids respectively, indicating that drug penetration may be significantly reduced in the latter. The results demonstrate the need for biomimetic models during initial drug testing and evaluation.  相似文献   
107.
Background: Status epilepticus (SE) is a neurological disorder characterized by a prolonged epileptic activity followed by subsequent epileptogenic processes. The aim of the present study was to evaluate the early effects of topiramate (TPM) and lacosamide (LCM) treatment on oxidative stress and inflammatory damage in a model of pilocarpine-induced SE. Methods: Male Wistar rats were randomly divided into six groups and the two antiepileptic drugs (AEDs), TPM (40 and 80 mg/kg, i.p.) and LCM (10 and 30 mg/kg, i.p.), were injected three times repeatedly after pilocarpine administration. Rats were sacrificed 24 h post-SE and several parameters of oxidative stress and inflammatory response have been explored in the hippocampus. Results: The two drugs TPM and LCM, in both doses used, succeeded in attenuating the number of motor seizures compared to the SE-veh group 30 min after administration. Pilocarpine-induced SE decreased the superoxide dismutase (SOD) activity and reduced glutathione (GSH) levels while increasing the catalase (CAT) activity, malondialdehyde (MDA), and IL-1β levels compared to the control group. Groups with SE did not affect the TNF-α levels. The treatment with a higher dose of 30 mg/kg LCM restored to control level the SOD activity in the SE group. The two AEDs, in both doses applied, also normalized the CAT activity and MDA levels to control values. In conclusion, we suggest that the antioxidant effect of TPM and LCM might contribute to their anticonvulsant effect against pilocarpine-induced SE, whereas their weak anti-inflammatory effect in the hippocampus is a consequence of reduced SE severity.  相似文献   
108.
Breast cancer is the most frequent cancer in the female population worldwide. The role of germline genetic variability in cytochromes P450 (CYP) in breast cancer prognosis and individualized therapy awaits detailed elucidation. In the present study, we used the next-generation sequencing to assess associations of germline variants in the coding and regulatory sequences of all human CYP genes with response of the patients to the neoadjuvant cytotoxic chemotherapy and disease-free survival (n = 105). A total of 22 prioritized variants associating with a response or survival in the above evaluation phase were then analyzed by allelic discrimination in the large confirmation set (n = 802). Associations of variants in CYP1B1, CYP4F12, CYP4X1, and TBXAS1 with the response to the neoadjuvant cytotoxic chemotherapy were replicated by the confirmation phase. However, just association of variant rs17102977 in CYP4X1 passed the correction for multiple testing and can be considered clinically and statistically validated. Replicated associations for variants in CYP4X1, CYP24A1, and CYP26B1 with disease-free survival of all patients or patients stratified to subgroups according to therapy type have not passed a false discovery rate test. Although statistically not confirmed by the present study, the role of CYP genes in breast cancer prognosis should not be ruled out. In conclusion, the present study brings replicated association of variant rs17102977 in CYP4X1 with the response of patients to the neoadjuvant cytotoxic chemotherapy and warrants further research of genetic variation CYPs in breast cancer.  相似文献   
109.
An experimental investigation of the performance of natural, mechanical and hybrid ventilation systems was carried out in an urban measurement campaign during summer period 2002 in Athens, Greece. Three building apartments characterized by different geometry and located in two street canyons with different orientation were studied. The aim was to show the impact of the urban environment on the ventilation efficiency of natural and hybrid systems. The tracer gas decay method has been applied during the experimental procedures with one (N2O) and two tracer gases (N2O and SF6). Based on the results of air-exchange rates using multizone methods from a previous study, a further analysis is performed in the present work for the evaluation of the performance of different ventilation systems in urban conditions, with emphasis on the ventilation efficiency. A methodology to estimate the air-exchange efficiency, on the basis of room mean age of air, in multitracer gas experiments is introduced. In spite of the reduced wind speeds due to the canyon effect, appreciable ventilation rates can be obtained with natural ventilation, especially when cross-ventilation with two or more windows is measured. For single-sided ventilation or under calm conditions, hybrid ventilation has only a slight advantage over natural, either in terms of air-exchange rates or of air-exchange efficiencies.  相似文献   
110.
The new water quality protection approach of the EU combines the control of emissions with instream Environmental Quality Standards (=EQS). Since 1 April 2006 and actually relevant in the version of 2010 in Austria, priority substances from list A of the EUROPEAN DIERECTIVE 76/464 and further EQS of relevant chemical substances (list B), identified by a national risk assessment, have to be reached to achieve a good ecological state in the surface water (Edict for Water Quality Standards, 2006; changes to the Edict for Water Quality Standards 2010). The practical assessment of these substances after point source emissions is prescribed in the Edict, but rarely carried out. In this paper, two substances, namely: (1) ammonium (list B); and (2) nonylphenol, an endocrine disrupting compound (list A) are presented to discuss: (i) the improvement of treatment efficiency due to the upgrade of a large Waste Water Treatment Plant (=WWTP); (ii) the relevance of mixing processes and modelling as a method to control EQS after point source emissions; and (iii) the improvement of water quality in the ambient surface waters. It is shown that the improved treatment in the case of nonylphenol leads to emission values which fall below the EQS, making an assessment unnecessary. In the case of ammonium emission, values are significantly reduced and violation of EQS is avoided, while mixing modelling is shown to be a suitable instrument to address the resulting instream concentrations at different border conditions.  相似文献   
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