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• Author or Editor: H. Sun
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## On a generalization of Hua’s theorem with five squares of primes

Acta Mathematica Hungarica
Authors:
G. Lü
and
H. Sun

## Abstract

We sharpen Hua’s theorem with five squares of primes by proving that every sufficiently large integer N congruent to 5 modulo 24 can be written in the form
\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} $$N = p_1^2 + p_2^2 + p_3^2 + p_4^2 + p_5^2$$ \end{document}
with p 1
\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} $$N^{\tfrac{{49}} {{288}}}$$ \end{document}
.
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## On the Lebesgue function of Hermite-Fejér interpolation for Laguerre abscissas

Acta Mathematica Hungarica
Author:
X. -H. Sun
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## On problems of approximation inL 2 spaces

Acta Mathematica Hungarica
Author:
X. H. Sun
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## Neutron activation analysis of organohalogens in Chinese human hair

Journal of Radioanalytical and Nuclear Chemistry
Authors:
H. Zhang
,
Z. Chai
,
H. Sun
, and
H. Xu

## Abstract

To effectively extract organohalogens from human hair, two factors, the extracting time and hair length on the extraction efficiency of organohalogens were studied by neutron activation analysis (NAA) and gas chromatograph-electron capture detector (GC-ECD), respectively. Furthermore, the concentrations of extractable organohalogens (EOX) and extractable persistent organohalogens (EPOX) in hair samples from angioma and control babies were also measured by the established method. The results indicated that the optimal Soxhlet-extraction time for EOX and EPOX in hair was from 8 to 11 hours, and the extraction efficiencies for organochlorine pesticides in hair were in the order of powder >2 mm>5 mm. Also, the mean levels of EOC1 and EPOC1 in hair of the angioma babies were significantly higher than those in the control babies (P EOC1<0.01; P EPOC1<0.05), which implied the possible relationship between the environmental pollution and angioma.

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## Research of thermal decomposition of hydrated methanesulfonates

Journal of Thermal Analysis and Calorimetry
Authors:
J. Tian
,
H. Jiang
,
H. Gong
, and
Z. Sun

## Abstract

Hydrated methanesulfonates Ln(CH3SO3)3 nH2O (Ln=La, Ce, Pr, Nd and Yb) and Zn(CH3SO3)2 nH2O were synthesized. The effect of atmosphere on thermal decomposition products of these methanesulfonates was investigated. Thermal decomposition products in air atmosphere of these compounds were characterized by infrared spectrometry, the content of metallic ion in thermal decomposition products were determined by complexometric titration. The results show that the thermal decomposition atmosphere has evident effect on decomposition products of hydrated La(III), Pr(III) and Nd(III) methanesulfonates, and no effect on that of hydrated Ce(III), Yb(III) and Zn(II) methanesulfonates.

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## Doppler-broadened boron peak analysis by using a modified spectral decomposition algorithm

Journal of Radioanalytical and Nuclear Chemistry
Authors:
G. Sun
,
C. Park
, and
H. Choi

## Abstract

Doppler broadening of a 477.6 keV line combined with a recoil of an excited Li nucleus is the characteristic of PGAA, which leads to complicated gamma-ray spectrum which is difficult to analyze. For this solution, a modified algorithm for an automated analysis of the Doppler-broadened peak spectrum is presented. The modified algorithm maintained the consistency of a Doppler-broadened peak with the finest analysis algorithm used for a Gaussian gamma-ray peak analysis in the HYPERMET code.

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## Prompt k 0-factors and relative gamma-emission intensities for the strong non-1/ v absorbers 113Cd, 149Sm, 151Eu and 155,157Gd

Journal of Radioanalytical and Nuclear Chemistry
Authors:
G. Sun
,
S. Byun
, and
H. Choi

## Abstract

Prompt k 0-factors relative to chlorine and relative g-emission intensities were determined for the strong non-1/v absorbers 113Cd, 149Sm, 151Eu,155Gd and 157Gd. Measurements were performed using the SNU-KAERI prompt gamma activation analysis (PGAA) facility at the Korea Atomic Energy Research Institute (KAERI). For proper experimental determination of the prompt k 0-factors, the effective g-factor and cadmium ratio were taken into account, in consideration of the effects from the non-1/v capture cross section and neutron spectrum in the thermal and epithermal energy region. By using the actual spectrum of the neutron beam in this study, the effective g-factor was obtained by calculation, and the influence of epithermal neutrons on the capture rate was corrected by measuring the cadmium ratio for each non-1/v target isotope. The measured prompt k 0-factors were used to check the consistency between the existing dataset of the absolute g-emission intensity and the 2200 m/s capture cross section for these isotopes.

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## Investigation of delta-aminolevulinic acid dehydratase polymorphism affecting hematopoietic, hepatic and renal toxicity from lead in Han subjects of southwestern China

Acta Physiologica Hungarica
Authors:
H. Wan
,
J. Wu
,
P. Sun
, and
Yuelin Yang

This study is to explore the effect of ALAD polymorphism on hematopoietic, hepatic and renal toxicity from lead in occupational exposure workers

Open access

## Effects of different cultivation practices on soil temperature and wheat spike differentiation

Cereal Research Communications
Authors:
Y. Wang
,
S. Chen
,
H. Sun
, and
X. Zhang

Field cultivation practices affected soil temperature that influenced the crop development of winter crops. This study was undertaken to determine the effects of different mulch materials, tillage depths and planting methods on spike differentiation of winter wheat ( Triticum aestivum L.). The field experiment was consisted of three tests: (i) polythene mulch, straw mulch and no mulch; (ii) ridge planting and furrow planting; (iii) conventional tillage and shallow tillage. The results showed that soil temperature was affected by different practices. The higher soil temperature under polythene mulch resulted in the earlier initiation of spike differentiation, while straw mulch decreased soil temperature in spring that delayed the initiation compared with the non-mulch treatment. The spike initiation under ridge planting started earlier than that of furrow planting. Reduced tillage delayed the initiation compared with the conventional tillage. Duration of spike differentiation lasted longer under earlier starting of initiation that increased the grain numbers per spike. Other yield component characters were not affected by soil temperature. It was concluded that in the North China Plain where grain-filling duration of winter wheat was limited, agricultural practices that increased soil temperature in spring were favorable for grain production.

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## A radioreagent method for determination of traces of phosphorus in high-purity silicon

Journal of Radioanalytical and Nuclear Chemistry
Authors:
P. Chen
,
J. Chen
,
H. Sun
, and
M. Yang

## Abstract

The present study explores the feasibility of the determination of phosphorus at the extreme trace levels in high-purity silicon by radioreagent method. After silicon dissolution with hydrofluoric and nitric acids and matrix volatilization, 12-molybdophosphoric acid (12-MPA) is formed by the addition of the radioreagent,99MoO 4 2– , in nitric acid medium and then extracted into isobutyl acetate. By plotting the phosphorus content against the radioactivity of99Mo in the organic phase, a linear relationship persisting down to 5 ng is obtained. Special effort has been made to the elimination of the unreacted99MoO 4 2– reagent and the optimal control of phosphorus blank introduced through the multistage analytical procedure in order to ensure reliable determination of phosphorus at the ppb level.

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