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51.
This study was a factorial experiment with a completely randomized design and three replications. The four levels of methanol spraying were used. Spraying was carried out three times during the growing season at 10‐day intervals beginning at 4 weeks after sowing. The spraying of solution continued until saturation of droplets on the leaves was achieved. The levels of water‐deficit stress applied were nonstress, moderate water stress and severe water stress. The results showed that there was a significant difference (P ≤ 0.05) between the methanol and water‐deficit stress treatments for chlorophyll (Chl) a and Chl b, carotenoid, total chlorophyll, net photosynthesis (PN), intercellular CO2 (Ci), maximal quantum yield of photosystem II photochemistry (Fv/Fm), leaf moisture, water use efficiency and relative water content. The application of foliar methanol at all levels of water‐deficit stress significantly decreased the catalase activity of the roots. Under all levels of water‐deficit stress, the 30% (v/v) methanol treatment significantly decreased peroxidase activity in the roots over that for the control. The results suggest that foliar application of methanol can decrease the negative effects of water‐deficit stress on Phaseolus vulgaris L. cv. Sadry.  相似文献   
52.
The facile synthesis of several 1,3‐diazabicyclo[3.1.0]hex‐3‐ene derivatives with varying substitutions such as 2‐methyl‐6‐(4‐nitrophenyl)‐2,4‐diphenyl‐( 1 ), 2‐methyl‐6‐(4‐nitrophenyl)‐4‐phenyl‐2‐(pyridin‐3‐yl)‐( 2 ), 2‐(furan‐2‐yl)‐6‐(4‐nitrophenyl)‐4‐phenyl‐( 3 ), 2‐(furan‐2‐yl)‐6‐(3‐nitrophenyl)‐4‐phenyl‐( 4 ), 6‐(3‐nitrophenyl)‐2,4‐diphenyl‐( 5 ) and 6‐(4‐chlorophenyl)‐4‐(3‐nitrophenyl)‐2‐phenyl‐( 6 ) that all behave as “intelligent materials” are reported.  相似文献   
53.
Journal of Inclusion Phenomena and Macrocyclic Chemistry - Molecular dynamics simulations were performed in aqueous solution to elucidate an atomistic level picture of complex formation between...  相似文献   
54.
Hepatocellular carcinoma (HCC) is an invasive form of hepatic cancer arising from the accumulation of multiple genetic alterations. In this study, the causal role of disturbed canonical Wnt/β-catenin pathway was approved, and some of HCC-driven important gene candidates were determined. MicroRNAs (miRNAs), small non-coding RNAs, are the key regulators of important cancer genes, and their participation in tumorigenesis has been shown. By reviewing literature, WNT1 gene with functional significance was selected to approve miRNAs as new subjects for targeted therapy.For proper and fast miRNA detection and also confirmation of the role of bioinformatics in obtaining practical data, we benefited from different bioinformatics tools such as TargetScan, miRanda, and DIANA. In order to use an HCC model, we used HepG2 cell line. Luciferase assay was applied to assess the ability of the selected miRNAs in targeting WNT1 3′-UTR. To overexpress the selected miRNA in HepG2 cell line, viral construct was prepared. Quantitative real-time PCR was performed to evaluate selected miRNA and target gene expression levels. miR-122 was selected according to data concerning various bioinformatics tools.miR-122 was downregulated and WNT1 gene expression was upregulated in HepG2 cell line. After viral construct transduction, miR-122 expression was elevated and WNT1 expression was notably declined. Finally, we introduced WNT1 gene as one of the important genes in HCC, and also, we showed that miR-122 can regulate WNT1 gene expression.Moreover, our study determines the potential of bioinformatics analyses in providing accurate and reliable data for miRNA: messenger RNA (mRNA) prediction.  相似文献   
55.
The synthesis and characterization of substituted ONNO-donor salen-type Schiff base complexes of general formula [MIII(L)Cl] (L = Schiff base ligand, M = Fe, Co) is reported. The complexes have been applied as catalysts for the coupling of carbon dioxide and styrene oxide in the presence of tetrabutylammonium bromide as a co-catalyst. The reactions were carried out under relatively low-pressure and solvent-free conditions. The effects of the metal center, ligands, and various substituents on the peripheral sites of the ligand on the coupling reaction were investigated. The catalyst systems were found to be selective for the coupling of CO2 and styrene oxide, resulting in cyclic styrene carbonate. The cobalt(III) complex with no substituents on the ligand showed higher activity (TON = 1297) than the corresponding iron(III) complex (TON = 814); however, the iron(III)-based catalysts bearing electron-withdrawing substituents on the salen ligands (NEt3, TON = 1732) showed the highest catalytic activity under similar reaction conditions. The activity of one of the cobalt(III) complexes toward the coupling of 1-butene oxide, cyclohexene oxide and propylene oxide with CO2 was evaluated, revealing a notable activity for the coupling of 1-butene oxide.  相似文献   
56.
In this study, we used voltammetric method in order to examine the electrochemical behavior of BPA. Hence, we constructed a new electrochemical sensor to detect BPA on the basis of the modified carbon paste electrode using FeNi3/CuS/BiOCl as a novel nanocomposite. Results showed that when using optimized conditions, the new BPA sensor has a wide linear range between 0.1 μM and 300 μM, lower limit of detection of 0.05 μM, and good reproducibility and stability. Based on the findings, it could be concluded that our sensor can be substantially utilized for detecting BPA in the food samples with reasonable outputs.  相似文献   
57.
The sulfonated polyetherimide (sPEI) was synthesized by direct sulfonation method using chlorosulfonic acid as a sulfonating agent. Different sulfonation degrees of sPEI was obtained by varying the ratio of PEI to chlorosulfonic acid and reaction time. Then, sulfonated polyetherimide was blended with polyethylene glycol (PEG) and thermally cross-linked in order to achieve high performance proton exchange membrane. It was found that the addition of PEG resulted in a significant increase in porosity and water uptake of the membranes, which favored proton transport at low temperature. The maximum proton conductivity was 11 mS/cm at 75°C for the blend membrane containing 20% PEG. The sulfonation and blend modification of PEI were characterized by attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy.  相似文献   
58.

The parameters of foaming and nano-clay percentage on the density of polymer foam and cell size with the PVC field is studied. Cell size and density have a significant impact on the strength of foam and its insulation (including sounds and thermal insulation). By optimizing cell size and density, foam can be produced with the best mechanical properties. In foaming process of the nanocomposite samples by mass method, the design variables (input parameters) are foaming time and temperature and MMT content. The controlled elitist multi-objective GA is applied to minimize both the foam density and the cell size. To that end, the population size and the Pareto fraction are selected as 100 and 0.5, respectively. The noninferior solution obtained by the controlled elitist multi-objective GA is illustrated. When both the MMT and the temperature are high, the resulting foam does not have ideal characteristics.

  相似文献   
59.
Research on Chemical Intermediates - 4-Sulfophthalic acid (4-H3SPA) solution 50 wt% in H2O has been effectively catalyzed the synthesis of a series of biologically relevant...  相似文献   
60.
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