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431.
谢英娜  高子伟  高玲香  刘昭铁 《化学学报》2007,65(13):1280-1284
采用溶胶-凝胶法制备了不同TiO2含量的杯[6]芳烃乙酸/TiO2 (CA/TiO2)杂化材料. 通过溶剂抽提实验和FT-IR测试表明杂化材料中有机无机两相间存在着化学键. 通过XRD, SEM, TGA对材料的结构和性能进行表征. 结果表明: 当TiO2的含量w为60%时, 材料表面均匀光滑, 有机无机两相相容性和材料的热稳定性能最好, 但w(TiO2)≤40%时, 难以获得两相均一的杂化材料.  相似文献   
432.
Alteration of insect growth regulators by the action of inhibitors is becoming an attractive strategy to combat disease-transmitting insects. In the present study, we investigated the larvicidal effect of 1,2,3-triazolyl-pyrimidinone derivatives against the larvae of the mosquito Anopheles arabiensis, a vector of malaria. All compounds demonstrated insecticidal activity against mosquito larvae in a dose-dependent fashion. A preliminary study of the structure–activity relationship indicated that the electron-withdrawing substituent in the para position of the 4-phenyl-pyrimidinone moiety enhanced the molecules’ potency. A docking study of these derivatives revealed favorable binding affinity for the sterol carrier protein-2 receptor, a protein present in the intestine of the mosquito larvae. Being effective insecticides against the malaria-transmitting Anopheles arabiensis, 1,2,3-triazole-based pyrimidinones represent a starting point to develop novel inhibitors of insect growth regulators.  相似文献   
433.
In this article, we introduce and analyze arbitrary-order, locally conservative hybrid discontinuous Galkerin methods for linearized Navier–Stokes equations. The unknowns of the global system are reduced to trace variables on the skeleton of a triangulation and the average of pressure on each cell via embedded static condensation. We prove that the lifting operator associated with trace variables is injective for any polynomial degree. This generalizes the result in (Y. Jeon and E.-J. Park, Numerische Mathematik 123 [2013], no. 1, pp. 97–119), where quadratic and cubic rectangular elements are analyzed. Moreover, optimal error estimates in the energy norm are obtained by introducing nonstandard projection operators for the hybrid DG method. Several numerical results are presented to show the performance of the algorithm and to validate the theory developed in the article.  相似文献   
434.
利用密度泛函理论和k·p模型方法对半哈斯勒化合物XYZ(X=Li,Na,K;Y=Ag,Au;Z=S,Se,Te)进行了研究.半哈斯勒化合物XYZ可以看作是由Xn+离子填充到闪锌矿YZn-晶格组成.它们的s态电子形成双重简并Γ6((2))能带,p-d杂化态形成双重简并Γ7((2))能带和四重简并Γ8((4))能带.当s型的Γ6((2))能带高于Γ7((2))和Γ8((4))能带时,化合物为普通绝缘体.然而,当s型Γ6((2))能带低于Γ7((2))和Γ8((4))能带时,化合物是拓扑非平庸绝缘体(如NaAuS)或半金属(如NaAuTe),这还要取决于负或正...  相似文献   
435.
Plasmon hybridization between closely spaced nanoparticles yields new hybrid modes not found in individual constituents, allowing for the engineering of resonance properties as well as field enhancement capabilities of metallic nanostructure. Experimental verifications of plasmon hybridization have been thus far mostly limited to optical frequencies, as metals cannot support surface plasmons at longer wavelengths. Here, we introduce the concept of ‘spoof plasmon hybridization’ in highly conductive metal structures and investigate experimentally the interaction of localized surface plasmon resonances (LSPR) in adjacent metal disks corrugated with subwavelength spiral patterns. We show that the hybridization results in the splitting of spoof plasmon modes into bonding and antibonding resonances analogous to the molecular orbital rule and plasmonic hybridization in optical spectrum. These hybrid modes can be manipulated to produce enormous field enhancement (>5000) by tuning the separation between disks or alternatively, the disk size, which effectively changes the relative gap size. The impact of the radiation loss is considered to find out the optimum disk size that maximizes field enhancement capabilities. Our investigation not only extends the range of applicability of the hybridization model, but also provides insightful guidance to exporting the exciting applications associated with plasmon hybridization to lower spectral range.

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436.
In order to improve the survival rate of oral squamous cell carcinoma (OSCC) patients, a reliable diagnostic method for early OSCC detection is required that is minimally invasive, less burdensome to the patient, and has high sensitivity and specificity. Therefore, we performed the detection of abnormal methylation at three locations in the hTERT promoter region of oral exfoliated cells by employing the ferrocenylnaphthalene diimide (FND)-based electrochemical hybridization assay (FND-EHA) using three types of DNA probe-immobilized electrodes. We also performed liquid cytology using oral exfoliated cells and compared these obtained data to evaluate whether FND- EHA can be used as an OSCC screening system. The results showed a good correlation between this method and conventional OSCC screening, and cytology. In addition, FND-EHA was also able to determine samples that had been ambiguously determined by liquid cytology. This indicates that FND-EHA may be useful as an OSCC screening system.  相似文献   
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