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• Author or Editor: P. Wang
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## A gap phenomenon on Riemannian manifolds with reverse volume pinching

Acta Mathematica Hungarica
Author:
P. Wang

## Abstract

Let M n be an n(≧ 3)-dimensional compact, simply connected Riemannian manifold without boundary and S n be the unit sphere of the Euclidean space R n+1. By two different means we derive an estimate of the diameter whenever the manifold considered satisfies that the sectional curvature K M ≦ 1, while Ric (M) ≧
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \usepackage{bbm} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $$\tfrac{{n + 2}}{4}$$ \end{document}
and the volume V (M) ≦
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \usepackage{bbm} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $$\tfrac{3}{2}$$ \end{document}
(1 + η)V (S n ) for some positive number η depending only on n. Consequently, a gap phenomenon of the manifold will be given according to the estimate of the diameter.
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## A differentiable sphere theorem on manifolds with reverse volume pinching

Acta Mathematica Hungarica
Author:
P. Wang

## Abstract

Based on the celebrated 1/4-pinching sphere theorem, we prove a differentiable sphere theorem on Riemannian manifolds with reverse volume pinching.

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## Influence of initial casting temperature and dosage of fly ash on hydration heat evolution of concrete under adiabatic condition

Journal of Thermal Analysis and Calorimetry
Authors:
J. Wang
and
P. Yan

## Abstract

The calorimetric data of binders containing pure Portland cement, 20% fly ash, 20% slag and 10% silica fume respectively are determined at different initial casting temperatures using an adiabatic calorimeter to measure the adiabatic temperature rising of concrete. The calorimetric data of binders with different dosages of fly ash at two water binder ratios (w/b) are determined, too. Elevation of initial casting temperature decreases the heat evolution of binder, enhances the heat evolution rate of binder and increases the heat evolution rate of binder at early age. The dosage of fly ash in concrete has different effects on the heat evolution of binder with different w/b. At high w/b ratio the heat evolution of binder decreases when dosage of fly ash increases. At low w/b ratio the heat evolution of binders increases when dosage of fly ash increases from 0 to 40% of total binder quantity. The heat evolution of binder decreases after the dosage of fly ash over 40%. An appropriate dosage of fly ash in binder benefits the performance of concrete at low w/b ratio.

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## The effects of fast neutron, gamma-ray and combined radiations on the thermal decomposition of ammonium perchlorate powder-aluminum particle mixtures

Journal of Thermal Analysis and Calorimetry
Authors:
P. Herley
,
C. Wang
,
G. Varsi
, and
P. Levy

## Abstract

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## Thorium and uranium determinations in acrylic by neutron activation analysis

Journal of Radioanalytical and Nuclear Chemistry
Authors:
P. Jagam
,
J. Wang
, and
J. Simpson

## Abstract

Improvements in the detection limits of thorium and uranium in acrylics by neutron activation analysis are described. The average of results from 10 g samples was found to be higher than the results from 450 g samples taken from the same acrylic sheet. Using eighteen large (450 g) samples from a single sheet of acrylic gave an average value of 3.2±0.3 pg/g thorium and 1.1±0.7 pg/g uranium. Interpretation of the results is discussed. Epithermal neutron activation with Cd shielded irradiations did not improve the detection sensitivity for thorium.

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## Determination of specific surface area for uranium compounds

Journal of Radioanalytical and Nuclear Chemistry
Authors:
P. Cong
,
X. Yang
, and
R. Wang

## Abstract

A new method of thermal desorption chromatography, in which hydrogen is used as carrier instead of helium, and a water bath instead of an air bath, is presented for determining the specific surface area of uranium compounds. The method proposed has a higher accuracy and a better applicability.

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## Characterization of the effect of short-term high temperature and vibration on wine by quantitative descriptive analysis and solid phase microextractiongas chromatography-mass spectrometry

Acta Alimentaria
Authors:
P. Zhao
,
H. Wang
, and
H. Li

The effect of short-term higher ambient temperature (HT) and continuous vibration (CV) treatment was comparatively characterized by sensory evaluation and chemical analysis. Results of quantitative descriptive analysis of modified frequency (MF) showed that HT causes both in red wine and white wine a decrease of fruity and floral characters, an unbalance of taste, and a shortness of aftertaste length. CV wine showed very close sensory characters to control in most terms evaluated. Seventy-four volatile compounds were quantitative analysed by solid phase microextractiongas chromatography-mass spectrometry, and the principal component analysis (PCA) was conducted on the 23 volatiles of highest odour activity value (OAV). The concentrations of potential fruity and floral aroma attributors like isoamyl acetate, ethyl butanoate, ethyl 2-methylbutanoate, ethyl hexanoate, ethyl octanoate, β-damascenone, and linalool were lower in HT wine than that in original wine and CV wine.

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## Synchrotron radiation induced X-ray fluorescence at LURE

Journal of Radioanalytical and Nuclear Chemistry
Authors:
I. Brissaud
,
J. Wang
, and
P. Chevallier

## Abstract

Advantages of X-ray fluorescence with the use of Synchrotron Radiation are emphasized (intensity, polarization, tunability of energy). The experimental set-up and the fast computer system for the data reduction without standards are presented. The results are in good agreement with standard references. Examples of applications are presented: old coins and potteries were studied in archaeological domain; metal alloys were analyzed; element composition of bulk samples of volcanic rocks, sublimates and aerosols were determined.

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## Simultaneous determination of anthraquinone derivatives in Radix et Rhizoma Rhei-based medicines by ultra-performance LC-ESCI-MS/MS multiple reaction monitoring

Acta Chromatographica
Authors:
G.-Y. Wang
and
Y.-P. Shi

## Summary

A new method using ultra-performance liquid chromatography (UPLC) in combination with tandem mass spectrometry and a multiple reaction monitoring mode (UPLC-MS/MS-MRM) was developed for simultaneous quantitative determination of anthraquinone derivatives in Radix et Rhizoma Rhei-based medicines. A multi-mode electrospray/chemical ionization (ESCI) and negative ion mode with [M-H] and its fragments under collision-activated conditions were employed in MS/MS-MRM. The quantitative method was validated and applied to simultaneous determination of anthraquinone derivatives in 21 Radix et Rhizoma Rhei-based medicines. The limits of quantification were in the range of 3.90–9.09 ng mL−1. Average recoveries were between 95.5% and 99.8% with relative standard deviations from 1.8% to 5.3%.

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## Improved SPE-UPLC-UV-based method for the simultaneous determination of triclocarban and triclosan in wastewater

Acta Chromatographica
Authors:
P. Li
,
X. Liu
, and
X. Wang

Triclocarban (TCC) and triclosan (TCS) are used in a wide range of household and personal care products and have been the most frequently detected organic pollutants in both wastewater and surface water. This paper presented a rapid analytical method for simultaneous determination of TCC and TCS in wastewater. The method involves the extraction and cleanup of the target compounds by using silicon dioxide/polystyrene composite microspheres solid-phase extraction and detection with ultra-high-pressure liquid chromatography. Under the optimized conditions, the limits of detection were 0.028 μg/L and 0.040 μg/L for TCC and TCS, respectively. Under the concentrations of the spiking level ranging from 0.100 μg/L to 2.000 μg/L, the spiked recoveries of TCC and TCS in wastewater samples achieved in the range of 89.5–102.8% with RSD below 6.3% for TCC and 95.5–103.6% with RSD below 6.9% for TCS. This method was successfully used in monitoring the water samples from three traditional wastewater treatment plants.

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