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Abstract  

The constant-volume combustion energies of the lead salts of 2-hydroxy-3,5-dinitropyridine (2HDNPPb) and 4-hydroxy-3,5-dinitropyridine (4HDNPPb), ΔU c (2HDNPPb(s) and 4HDNPP(s)), were determined as –4441.922.43 and –4515.741.92 kJ mol–1 , respectively, at 298.15 K. Their standard enthalpies of combustion, Δc m H θ(2HDNPPb(s) and 4HDNPPb(s), 298.15 K), and standard enthalpies of formation, Δr m H θ(2HDNPPb(s) and 4HDNPPb(s), 298.15 K) were as –4425.812.43, –4499.631.92 kJ mol–1 and –870.432.76, –796.652.32 kJ mol–1 , respectively. As two combustion catalysts, 2HDNPPb and 4HDNPPb can enhance the burning rate and reduce the pressure exponent of RDX–CMDB propellant.

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Journal of Radioanalytical and Nuclear Chemistry
Authors:
H. J. Ding
,
Y. N. Niu
,
Y. B. Xu
,
W. F. Yang
,
S. G. Yuan
,
Z. Qin
, and
X. H. Zhou

Summary  

The extraction of protactinium with Aliquat 336 (methyl-tri-caprylyl ammonium chloride) in toluene, cyclohexane and chloroform from HCl, HNO3, H2SO4, HClO4, HF and mixed HCl-HF media was investigated by radioactive tracer technique. Distribution ratios of protactinium between the aqueous solution and the organic phase were determined as a function of shaking time, concentrations of acid in aqueous solution phase, extractant concentration and type of diluents in the organic phase. Aliquat 336 can almost quantitatively extract protactinium from strong HCl solution. At the same time, small amounts of HF in HCl solutions have a strong effect on Pa distribution.

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The aim of this study was to investigate postprandial effects of two Chinese liquors on s elected cardiovascular disease risk factors in humans. Sixteen healthy men were randomized into three groups in a three-way crossover study: tea-flavor liquor (TFL), traditional Chinese liquor (TCL) and water control (WC). Every subject consumed 60 mL of either liquor (45% (v/v) ethanol) or water together with a high-fat meal, respectively. Compared with baseline, serum uric acid was significantly increased in TFL group (0.5-hour: P = 0.012; 1-hour: P = 0.001; 2-hour: P = 0.008) and it was significantly decreased in WC group (1-hour: P = 0.001; 2-hour: P = 0.001; 4-hour: P < 0.001), while uric acid was non-significantly increased in the TCL group. High-sensitive C-reactive protein (hs-CRP) was significantly increased in the TCL (P = 0.014) and WC (P = 0.008) groups at postprandial 4 hours compared with baseline. There was no significant difference between groups during the postprandial period for these two parameters or other biochemical parameters. In conclusion, both liquors increased postprandial uric acid, and no significant difference was observed for the effects of TFL and TCL on the measured biochemical parameters.

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Protein and starch are important in wheat quality and yield. To understand the genetic relationship between protein and starch at the quantitative trait locus (QTL)/gene level, 168 doubled haploid (DH) lines were used at three locations over 2 years. The QTLs for proteinfraction contents and starch content were analyzed by unconditional and conditional QTL mapping. We detected 17 unconditional additive QTLs (four albumin QTLs, three globulin QTLs, six gliadin QTLs, four glutenin QTLs) controlling protein-fraction contents. We detected 19 conditional QTLs (five albumin QTLs, three globulin QTLs, five gliadin QTLs, six glutenin QTLs) based on starch content. Of these QTLs, QAlu1B, QGlo6A, QGli1B, QGli7A, QGlu1B and QGlu1D increased the protein-fraction contents independent of the starch content. These QTLs could regulate the usual inverse relationship between protein and starch in wheat seeds. The results could possibly be used in the simultaneous improvement of grain protein and starch content in wheat breeding.

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Abstract

Background and aims

Gambling disorder (GD) is a mental disorder with a relatively higher prevalence in university students compared to adolescents and adults. Its reciprocity with mental being indicators, such as psychological flourishing, would be expected, but prior to this study had not yet been empirically examined. In addition, the predictive value of purpose in life (PIL) on university students' GD and psychological flourishing also remained unknown. This 1-year longitudinal study was the first to test the potential bidirectional relationships among PIL, self-reported GD symptoms, and psychological flourishing.

Methods

In this study, a total of 283 university students (39.6% females; age = 18–27 years, M = 20.47, SD = 1.15) completed an anonymous questionnaire at both baseline and a year later in a follow-up study.

Results

The results of our cross-lagged analysis did not show the hypothesized reciprocity between GD symptoms and psychological flourishing (P > 0.05). However, PIL significantly predicted fewer GD symptoms (β = −0.23, P < 0.001) and higher levels of psychological flourishing (β = 0.30, P < 0.001) in the follow-up study. Moreover, psychological flourishing predicted PIL a year later.

Conclusion

The findings demonstrate the potential efficacy of purpose/meaning oriented interventions in gambling prevention and in well-being promotion programs.

Open access
Journal of Behavioral Addictions
Authors:
Ji-Bin Li
,
Anise M.S. Wu
,
Li-Fen Feng
,
Yang Deng
,
Jing-Hua Li
,
Yu-Xia Chen
,
Jin-Chen Mai
,
Phoenix K.H. Mo
, and
Joseph T.F. Lau

Abstract

Background and aims

Problematic online social networking use is prevalent among adolescents, but consensus about the instruments and their optimal cut-off points is lacking. This study derived an optimal cut-off point for the validated Online Social Networking Addiction (OSNA) scale to identify probable OSNA cases among Chinese adolescents.

Methods

A survey recruited 4,951 adolescent online social networking users. Latent profile analysis (LPA) and receiver operating characteristic curve (ROC) analyses were applied to the validated 8-item OSNA scale to determine its optimal cut-off point.

Results

The 3-class model was selected by multiple criteria, and validated in a randomly split-half subsample. Accordingly, participants were categorized into the low risk (36.4%), average risk (50.4%), and high risk (13.2%) groups. The highest risk group was regarded as “cases” and the rest as “non-cases”, serving as the reference standard in ROC analysis, which identified an optimal cut-off point of 23 (sensitivity: 97.2%, specificity: 95.2%). The cut-off point was used to classify participants into positive (probable case: 17:0%) and negative groups according to their OSNA scores. The positive group (probable cases) reported significantly longer duration and higher intensity of online social networking use, and higher prevalence of Internet addiction than the negative group.

Conclusions

The classification strategy and results are potentially useful for future research that measure problematic online social networking use and its impact on health among adolescents. The approach can facilitate research that requires cut-off points of screening tools but gold standards are unavailable.

Open access