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Abstract

The phase transition of TiN from the NaCl structure to the CsCl structure is investigated by the first-principles plane wave pseudopotential density functional theory method, and the thermodynamic properties of the NaCl structures are obtained through the quasi-harmonic Debye model. It is found that the pressures for transition from the NaCl structure to the CsCl structure are 364.1 GPa (for GGA) and 322.2 (for LDA) from equal enthalpies. The calculated ground state properties such as equilibrium lattice constant, bulk modulus, and its pressure derivative are in good agreement with experimental and theoretical data of others. Moreover, the dependences of the relative volume V/V 0 on the pressure P, the Debye temperature Θ D , and heat capacity C V on the pressure P and temperature T, as well as the variation of the thermal expansion α with temperature and pressure are also successfully obtained.

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Abstract

Li-ion batteries with LiFePO4/C composites are difficult to be charged at low temperatures. In order to improve the low temperature performance of LiFePO4/C power batteries, the charge–discharge characteristics were studied at different temperatures, and a new charging mode under low temperature was proposed. In the new charging mode, the batteries were excited by current pulses with the charge rates between 0.75 C and 2 C, while the discharge rates between 3 and 4 C before the conventional charging (CC–CV). Results showed that the surface temperature of Li-ion battery ascended to 3 °C at the end of pulse cycling when the environment temperature was −10 °C. Comparing with the conventional charging, the whole charge time was cut by 36 min (23.4%) and the capacity was 7.1% more at the same discharge rate, respectively.

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Rice sheath blight, caused by Rhizoctonia solani, is the most serious disease in the southern rice producing regions of China. The use of resistant varieties is the most economic strategy to control the disease. In this paper, a seedling inoculation method was used to evaluate rice germplasm resources for resistance to sheath blight. A total of 363 rice varieties were evaluated with a set of R. solani isolates. The results indicated that the rice varieties generally lacked resistance to R. solani, and no highly resistant/immune (HR) variety was found. However, two varieties displayed clear resistance (R) and 37 showed moderate resistance (MR) to the fungus. Overall, hybrid rice varieties have better resistance than conventional rice varieties, and among hybrid rice varieties, those with the II-32A sterile line genetic background were the most resistant. The results also indicated significant interactions between rice varieties and pathogen isolates, suggesting that an understanding of local R. solani populations is needed when recommending varieties to local growers.

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Acta Chromatographica
Authors:
Lianguo Chen
,
Qingwei Zhang
,
Yijing Lin
,
Xiaojie Lu
,
Zuoquan Zhong
,
Jianshe Ma
,
Congcong Wen
, and
Cheng Ding

An ultra-performance liquid chromatography–tandem mass spectrometry (UPLC–MS/MS) method was established to determine the hapepunine in mouse blood, and the pharmacokinetics of hapepunine after intravenous (1.0 mg/kg) and intragastric (2.5, 5, and 10 mg/kg) administrations was studied. Delavinone was used as an internal standard. The UPLC ethylene bridged hybrid (BEH) C18 column was used for chromatographic separation. The mobile phase consisted of acetonitrile and 0.1% formic acid with a gradient elution flow rate of 0.4 mL/min. Multiple reaction monitoring (MRM) mode was used for quantitative analysis of hapepunine in electrospray ionization (ESI) positive interface. Proteins from mouse blood were removed by acetonitrile precipitation. The verification method was established in accordance with the US Food and Drug Administration (FDA) bioanalytical method validation guidelines. In the concentration range of 1–1000 ng/mL, the hapepunine in the mouse blood was linear (r 2 > 0.995), and the lower limit of quantification was 1.0 ng/mL. In the mouse blood, the intra-day precision coefficient of variation (CV) was less than 12%, the inter-day precision CV was less than 14%. The accuracy ranged from 91.7% to 109.3%. The average recovery was higher than 76.7%, and the matrix effect was between 86.0% and 106.4%. The UPLC–MS/MS method was sensitive, rapid, and selective and was successfully applied to the pharmacokinetic study of hapepunine in mice. The absolute bioavailability of hapepunine was 22.0%.

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A simple and rapid high-performance liquid chromatographic (HPLC) method was established for simultaneous determination of butorphanol tartrate and ondansetron hydrochloride in analgesic mixture samples used for patient-controlled analgesia (PCA). The separation of butorphanol tartrate and ondansetron hydrochloride in PCA solution was carried out on phenomenex C18 column (4.6 mm × 150 mm, 5 μm) using 50 mM sodium acetate (pH 4.0) buffer and acetonitrile (72:28, v/v). Flow rate was 1.0 mL min−1 with a column temperature of 30 °C, and detection wavelength was carried out at 280 nm and 306 nm. Validation of the method was made in terms of specificity, linearity, accuracy, and intra- and inter-day precision, as well as quantification and detection limits. The developed method was successfully used to evaluate the chemical stability of butorphanol tartrate and ondansetron hydrochloride in analgesic mixtures at the usual concentration used for PCA.

Open access

Background and aims

Based on the foundations of Bandura’s social cognitive theory and theory of triadic influence (TTI) theoretical framework, this study was designed to examine the mediating role of positive outcome expectancy of Internet use in the relationship between social influence and Internet addiction (IA) in a large representative sample of senior high-school students in Taiwan.

Methods

Using a cross-sectional design, 1,922 participants were recruited from senior high schools throughout Taiwan using both stratified and cluster sampling, and a comprehensive survey was administered.

Results

Structural equation modeling and bootstrap analyses results showed that IA severity was significantly and positively predicted by social influence, and fully mediated through positive outcome expectancy of Internet use.

Discussion and conclusions

The results not only support Bandura’s social cognitive theory and TTI framework, but can also serve as a reference to help educational agencies and mental health organizations design programs and create policies that will help in the prevention of IA among adolescents.

Open access
Journal of Thermal Analysis and Calorimetry
Authors:
Xiao-Tao Wang
,
Ying-Kui Yang
,
Zhi-Fang Yang
,
Xing-Ping Zhou
,
Yong-Gui Liao
,
Chen-Chen Lv
,
Feng-Chih Chang
, and
Xiao-Lin Xie

Abstract  

Vinylated polyhedral oligomeric silsesquioxane (POSS-M) was prepared by the reaction of POSS containing amine groups with acrylic acid. Azobenzene liquid crystalline copolymer (LCP-POSS) was then synthesized with 6.0 mol% POSS-M and 94.0 mol% acrylate monomer containing azobenzene liquid crystalline moiety (Azo-M) by free-radical copolymerization. Homopolymer of Azo-M (LCP) was also synthesized under the same conditions. Their thermal properties and liquid crystallinity were characterized by Thermal gravimetric analysis (TG), differential scanning calorimetry (DSC), Wide-angle X-ray diffraction experiments (XRD) and polarized optical micrographs (POM). The results showed that LCP-POSS has higher thermal stability and glass transition temperature than pure LCP due to the incorporation of the rigid cage-like POSS. Especially, LCP-POSS exhibits enantiotropic smectic and nematic liquid crystalline behaviors, its smectic-nematic transition temperature (T SN) and nematic-isotropic transition temperature (T NI) are higher than those of pure LCP, which may promote and extend its applications on stimuli-responsive materials and devices.

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Stripe rust, caused by Puccinia striiformis Westend. f. sp. tritici Eriks., is a major disease that causes substantial losses to wheat production worldwide. The utilization of effective resistance genes in wheat cultivars is the preferred control of the disease. To study the inheritance of all-stage resistance in spring wheat cultivars Louise, WA008016, Express, Solano, Alturas and Zak from the Pacific Northwest (PNW) of the United States, the six cultivars were crossed with the Chinese susceptible variety Taichung 29. Single-spore isolates of CYR32 and CYR33, the predominant Chinese races of P. striiformis f. sp. tritici, were used to evaluate F1, F2 and BC1 generations for stripe rust resistance under controlled greenhouse conditions. Genetic analysis determined that Louise had one dominant resistance gene to CYR32, temporarily designated as YrLou. WA008016 had two dominant and one recessive resistance genes to CYR32, temporarily designated as YrWA1, YrWA2 and YrWA3, respectively. Express had a single recessive gene that conferred resistance to CYR32, temporarily designated as YrExp3. The two independent dominant genes in Solano conferring resistance to CYR32 were temporarily designated as YrSol1 and YrSol2. Alturas had two recessive genes for resistance to CYR32, temporarily designated as YrAlt1 and YrAlt2. Zak has one dominant gene for resistance to CYR33, temporarily designated as YrZak1. These six cultivars can be important resistance sources in Chinese wheat stripe rust resistance breeding.

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Journal of Radioanalytical and Nuclear Chemistry
Authors:
Qinfang Qian
,
Shaojin Yang
,
Yinan Yang
,
Bingru Chen
,
Guodong Liu
,
Han Lin
,
Wenzheng Lan
,
Xiaoheng Wen
,
Genyuan Ji
, and
Shusheng Ma

Abstract  

The radius of rabbits were fractured by operation and the contents of Ca, Na, Mg, Zn, Mn and Sr in bone crusts during the period between the first to seventh week after fracture were determined by INAA. The tests show that all the contents of 6 elements in bone crusts are higher than those in contrast lateral in the same rabbit. The elemental metabolism curves in both laterals are roughly parallel. The content of Ca in the fractured position is almost constant during healing, those of Mn, Mg and Zn change apparently, and that of Sr changes in different way with the other elements.

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