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Perovskite solar cells (PSCs) have recently received considerable attention due to the high energy conversion efficiency achieved within a few years of their inception. However, a machine learning (ML) approach to guide the development of high‐performing PSCs is still lacking. In this paper ML is used to optimize material composition, develop design strategies, and predict the performance of PSCs. The ML models are developed using 333 data points selected from about 2000 peer reviewed publications. These models guide the design of new perovskite materials and the development of high‐performing solar cells. Based on ML guidance, new perovskite compositions are experimentally synthesized to test the practicability of the model. The ML model also shows its ability to predict underlying physical phenomena as well as the performance of PSCs. The PSC model matches well with the theoretical prediction by the Shockley and Queisser limit, which is almost impossible for a human to find from an ensemble of data points. Moreover, strategies for developing high‐performing PSCs with different bandgaps are also derived from the model. These findings show that ML is very promising not only for predicting the performance, but also for providing a deeper understanding of the physical phenomena associated with the PSCs.  相似文献   
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Plasmonics - Raman spectroscopy (RS) is a modern scientific analytic fingerprint technique that detects, examines, and analyzes the constituent chemical composition of various substances...  相似文献   
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Background: Parkinson's disease (PD) is a common progressive neurodegenerative and the prevailing treatments are ineffective in the early stages of the disease. Therefore, other strategies must be devised to halt the steady decrease of dopaminergic neurons in the brain. In Parkinson's disease, a dysregulated ACE/Ang II/AT1R axis in the brain causes free radical damage, apoptosis, and neuronal destruction. Current PD treatments only alleviate symptoms and do not reverse the degradation mechanism of dopaminergic neurons. As a result, it is critical to discover alternate, dependable medicines for the treatment of Parkinson's disease. Method : In the present study, homology modelling of MAS receptor, in silico docking and molecular dynamic studies (MDS) were employed to determine the efficacy of flavonoids as MASR activators. Result : The flavonoids Pterosupin and Amentoflavone exhibited best binding and therefore, the stability of these complexes were evaluated with MDS studies. The Pterosupin-MASR complex demonstrated better stability, stronger interactions and minimal fluctuation than the Amentoflavone-MASR complex. Conclusion : The data from the present study indicated that the flavonoid Pterosupin possesses better binding, favourable pharmacokinetic properties and stability. However, subsequent in vitro and in vivo assessments are necessary to validate its efficacy.  相似文献   
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Renewable fuels produced from biomass‐derived sugars are receiving increasing attention. Lignocellulose‐degrading enzymes derived from fungi are attractive for saccharification of biomass because they can be produced at higher titers and at significantly less cost than those produced by bacteria or archaea. However, their properties can be suboptimal; for example, they are subject to product inhibition and are sensitive to small changes in pH. Furthermore, increased thermostability would be advantageous for saccharification as increased temperature may reduce the opportunity for microbial contamination. We have developed a mutagenesis platform to improve these properties and applied it to increase the operating temperature and thermostability of the fungal glycosyl hydrolase Cel7A. Secretion of Cel7A at titers of 26 mg/L with limited hyperglycosylation was achieved using a Saccharomyces cerevisiae strain with upregulated protein disulfide isomerase, an engineered α‐factor prepro leader, and deletion of a plasma membrane ATPase. Using biased clique shuffling (BCS) of 11 Cel7A genes, we generated a small library (469) rich in activity (86% of the chimeras were active) and identified 51 chimeras with improved thermostability, many of which contained mutations in the loop networks that extend over the enzyme's active site. This BCS library was far superior as a source of active and stable chimeras compared to an equimolar library prepared from the same 11 genes. Biotechnol. Bioeng. 2012; 109: 2710–2719. © 2012 Wiley Periodicals, Inc.  相似文献   
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The study was prompted by the lack of information on the role of thermophilic actinomycetes in hypersensitivity pneumonitis in India. It reports the occurrence of precipitating antibodies against clinically important thermophilic actinomycetes in the sera of a population sample of dairy herd workers, Nangali, Delhi. Of 112 workers investigated, 28 (25%) showed precipitins againstFaenia rectivirgula, 4 (3.2%) againstSaccharomonospora viridis, 2 againstThermoactinomyces thalpophilus and one each againstT. vulgaris andT. sacchari. The results of enzyme-linked immunosorbent assay (ELISA) indicated that IgG antibody activity againstF. rectivirgula was significantly higher in the symptomatic group than in the asymptomatic group (p<0.05) of workers and the controls (p<0.01). Significant difference inF. rectivirgula IgG activity was also obtained between the precipitin-positive symptomatic group and the precipitin-positive asymptomatic group (p< 0.05). In strong contrast, the IgG antibody activity againstT. thalpophilus was found to be uniformly low. A limited aeromicrobiological sampling of the dairy farm revealedS. viridis (55.8%) to be the commonest species followed byT. vulgaris (19.2%),T. thalpophilus (18.5%),F. rectivirgula (5%) andT. sacchari (15%). On the basis of suggestive clinical and laboratory findings, farmer's lung disease was suspected in four dairy herd workers. A comprehensive clinical evaluation including pulmonary function studies on the dairy herd workers and their long-term follow-up is indicated to determine the extent of respiratory morbidity caused byF. rectivirgula, S. viridis, T. thalpophilus, T. sacchari andT. vulgaris in India.  相似文献   
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Summary In cereal-legume crop rotation system, better Rhizobium symbiosis was obtained by double inoculation,i.e., when the preceeding cereal crop of maize was also inoculated with the same Rhizobium strain, used to inoculate the following legume crop of green gram or groundnut.  相似文献   
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