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71.
NbFeSb‐based half‐Heusler alloys have been recently identified as promising high‐temperature thermoelectric materials with a figure of merit zT > 1, but their thermal conductivity is still relatively high. Alloying Ta at the Nb site would be highly desirable because the large mass fluctuation between them could effectively scatter phonons and reduce the lattice thermal conductivity. However, practically it is a great challenge due to the high melting point of refractory Ta. Here, the successful synthesis of Ta‐alloyed (Nb1?xTax)0.8Ti0.2FeSb (x = 0 – 0.4) solid solutions with significantly reduced thermal conductivity by levitation melting is reported. Because of the similar atomic sizes and chemistry of Nb and Ta, the solid solutions exhibit almost unaltered electrical properties. As a result, an overall zT enhancement from 300 to 1200 K is realized in the single‐phase Ta‐alloyed solid solutions, and the compounds with x = 0.36 and 0.4 reach a maximum zT of 1.6 at 1200 K. This work also highlights that the isoelectronic substitution by atoms with similar size and chemical nature but large mass difference should reduce the lattice thermal conductivity but maintain good electrical properties in thermoelectric materials, which can be a guide for optimizing the figure of merit by alloying.  相似文献   
72.
决明子的研究进展   总被引:13,自引:0,他引:13  
本文从原植物及生药学研究、化学成分、药理研临、临床应用及开发利用等方面对决明子的国内外研究进展进行了综述,为该药的进一步研究及开发提供了参考。  相似文献   
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A strain, designated as FM-6, was isolated from fish. Based on the results of phenotypic, physiological characteristics, genotypic and phylogenetic analysis, strain FM-6 was finally identified as Paenibacillus sp. When albendazole was provided as the sole carbon source, strain FM-6 could grow and transform albendazole. About 82.7 % albendazole (50 mg/L) was transformed by strain FM-6 after 5 days incubation at 30 °C, 160 rpm. With HPLC–MS method, the transforming product of albendazole was researched. Based on the molecular weight and the retention time, product was identified as albendazole sulfoxide and the transforming pathway of albendazole by strain FM-6 was proposed finally. The optimum temperature and pH for the bacterium growth and albendazole transformation by strain FM-6 were both 30 °C and 7.0. Moreover, the optimum concentration of albendazole for the bacterium growth was 50 mg/L. Coupled with practical production, 50 mg/L was the optimum concentration of albendazole transformation for strain FM-6. This study highlights an important potential use of strain FM-6 for producing albendazole sulfoxide.  相似文献   
75.
A Pichia pastoris system was used to express a single-chain variable fragment (scFv) antibody targeted against Metolcarb. The specific scFv gene was amplified from the phage-display scFv library and then subcloned into the expression vector pPICZα C. The resulting plasmid, pPICZα C-scFv, was linearized and transformed into P. pastoris strain X-33. A transformant named X-33-Pp-SMW-12-6, which showed strong expression of antibodies, was isolated, and the culture conditions, including methanol induction concentrations, inoculum densities, and pH, were optimized. Under optimal conditions, P. pastoris cultures yielded much higher levels of the scFv product than the Escherichia coli expression system. Immunochemical characterization of the scFv antibodies produced in P. pastoris indicated that the affinity and specificity of scFv against Metolcarb are comparable to those of scFv antibodies produced in E. coli. Recoveries of Metolcarb demonstrated that the P. pastoris-derived scFv antibodies can be used to determine the content of Metolcarb residue in environmental and agricultural samples using a competitive inhibition enzyme-linked immunosorbent assay. For our purposes, expression in Pichia proved to be an efficient and economical method for the large-scale production of functional scFv antibodies against Metolcarb for downstream applications.  相似文献   
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Background  

Current scoring functions are not very successful in protein-ligand binding affinity prediction albeit their popularity in structure-based drug designs. Here, we propose a general knowledge-guided scoring (KGS) strategy to tackle this problem. Our KGS strategy computes the binding constant of a given protein-ligand complex based on the known binding constant of an appropriate reference complex. A good training set that includes a sufficient number of protein-ligand complexes with known binding data needs to be supplied for finding the reference complex. The reference complex is required to share a similar pattern of key protein-ligand interactions to that of the complex of interest. Thus, some uncertain factors in protein-ligand binding may cancel out, resulting in a more accurate prediction of absolute binding constants.  相似文献   
78.
A new type of boron-rich, DSPC-free, unilamellar liposomes was formed using the novel dual-chain, ionic, nido-carborane lipid, K[nido-7-(C16H33OCH2)2CHOCH2-7,8-C2B9H11] (DAC-16), and cholesterol for encapsulation of an aqueous buffer core. Since DSPC was not necessary for the formation of stable DAC-16 liposomes, the boron concentration of these vesicles was increased dramatically to approximately 8.8 wt % in the dry lipid; these liposomes had a high bilayer boron incorporation efficiency of 98%. DSPC-free liposomes exhibited a size distribution pattern of 40-60 nm, which was in the range normally associated with selective tumor uptake. This size distribution was maintained throughout storage at room temperature for several months. Additionally, optimized liposome formulations incorporating DAC-16, DSPC, and cholesterol were identified having stable size distribution patterns after storage for more than two months at a variety of temperatures. Although animal studies indicate that DAC-16 liposomes are toxic, this new ionic nido-carborane lipid allows the formation of liposomes of high boron content for in vitro applications that require the delivery of large amounts of boron.  相似文献   
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Prostate cancer (PCa) is one of the most common malignant tumors in the world. Thioredoxin interacting protein (TXNIP) is downregulated in a variety of human tumors and plays an important role in tumor suppression. However, the expression level and biological functions of TXNIP in PCa have not been identified yet. Therefore, this study aims to investigate the expression and biological functions of TXNIP in PCa. We reported that the expression of TXNIP was significantly decreased in PCa and associated with clinicopathological features. Overexpression of TXNIP could significantly inhibited PC‐3 cells proliferation, migration, invasion, and glucose uptake. Additionally, overexpression of TXNIP could remarkably block cell cycle in the G0/G1 phase and promoted cell apoptosis. Furthermore, TXNIP expression correlated inversely with GLUT1 expression in PCa. Taken together, our results for the first time revealed that TXNIP was decreased in PCa. Moreover, TXNIP might act as a tumor suppressor of PCa and correlated with tumor occurrence and development. Our findings cast a new light on better understanding the occurrence and development of PCa and indicated that TXNIP might be favorable for PCa molecular target therapy.  相似文献   
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