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Square-Preserving and Symplectic Structure and Scheme for Quantum Sysyem

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Chinese Physics Letters 1996年第4期13卷 245-248页

作者： DING Pei-zhu WU Cheng-xun MU Ying-kui LI Yan-xin jin ming-xing Institute of Atomic and Molecular Physics Jilin UniversityChangchun 130023 Department of Physics Jilin UniversityChangchun 130023 Changchun Finance Manager College Changchun 130031

The time-dependent Schrodinger equation is a square-preserving and symplectic(SPS)*** canonical'equations of quantum systems are deduced by using eigenfanction *** normal-square of wavefunction of the quantum systems is an invariant integral of the canonical equations and then the symplectic schemes that based on both Cayley transformation and diagonal Fade approximation to exp(x)are also sq *** evaluated example show that the SPS approach is reasonable and effective for solving time-evolution of quantum system.

关键词： expansion. preserving quantum

Ionization and Fragmentation of Butanone Clusters Irradiated by Photons at 355 and 118 nm

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Chemical Research in Chinese Universities 2011年第3期27卷 508-511页

作者： SUN Chang-kai HU Zhan YANG Xue jin ming-xing HU Wen-cheng DING Da-jun Institute of Atomic and Molecular Physics Jilin University Changchun 130012 P. R. China

Time-of-flight（TOF） mass spectra of molecular butanone clusters were measured under the irradiation of photons at 355 and 118 nm. Butanone molecular parent ion and several series of butanone cluster fragments such as （CH3COC2H5）nH＋, （CH3COC2H5）nC2H5＋, （CH3COC2H5）nCH3CO＋ and （CH3COC2H5）nC2H5CO＋ were observed. Odd-even variation pattern in the intensity of （CH3COC2H5）nCH3CO＋ is obvious from n=4 to 8. A connection is es-tablished between the fragment clusters （CH3COC2H5）nCH3CO＋ and the neutral clusters （CH3COC2H5）n＋1 based on the consideration of butanone cluster dissociation mainly by losing a radical C2H5？. The stability variation of the neutral clusters calculated via the HF-B3LYP method based on DFT is in agreement with the observed phenomena experimentally, indicating （CH3COC2H5）n＋1（n＋1=5,7） with a ring structure are with higher stability over the adjacent even-number clusters.

关键词： Cluster Ionization Fragment Butanone

Ultrafast Photodissociation Dynamics of the F State of Sulfur Dioxide by Femtosecond Time-Resolved Pump-Probe Method

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Chinese Physics Letters 2011年第3期28卷 58-61页

作者： ZHANG Dong-Doug NI Qiang LUO Si-Zuo ZHANG jing LIU Hang XU Hai-Feng jin ming-xing DING Da-Jun Institute of Atomic and Molecular Physics Jilin UniversityChangchun 130012

A femtosecond pump-probe method is employed to study the dissociation dynamics of sulfur ***_(2)molecules are excited to the F state by absorbing two photons of 267nm femtosecond laser pulses,and ionized by 400nm laser pulses at different delay times between the two *** of both parent ions(SO_(2)^(+))and the fragment ions(SO^(+),S^(+)and O^(+)are *** S0_(2)^(+)transient can be well fitted to a biexponential decay comprising a fast and a slow component of 280fs and 2.97ps lifetimes,*** SO^(+)transient consists of two growth components of 270 fs and 2.50 *** results clearly show that the F state of S0_(2)dissociates along an S-0 *** transients of S^(+)and O^(+),however,have different behavior,which consist of a fast growth and a long decay component.A possible mechanism of the fragment formation is discussed to understand the dissociation dynamics of the F state of SO_(2).

关键词： Femto pump dissociation

Defocusing role in femtosecond filamentation: Higher-order Kerr effect or plasma effect?

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Chinese Physics B 2015年第11期24卷 54-58页

作者：李苏宇郭福明杨玉军金明星 Institute of Atomic and Molecular Physics Jilin University Jilin Provincial Key Laboratory of Applied Atomic and Molecular Spectroscopy (Jilin University)

The femtosecond filamentation in the classical and high-order Kerr （HOK） models is numerically investigated by adopting multi-photon ionization （MPI） cross section with different values. It is found that in the case that the MPI cross section is relatively small, there exists a big difference between the electron density as well as clamped intensity calculated in the classical model and those calculated in the HOK one, while in the case that the MPI cross section is relatively large, the electron density and clamped intensity calculated in the two models are nearly in agreement with each other, and under this circumstance, even if the higher-order nonlinear terms do exist, the free-charge generation and the associated defocusing in a filament are enough to mask their effects. The different behaviors of the maximum intensity and on-axis electron density at the collapse position with the pulse duration provides an approach to determine which effect plays the dominant defocusing role. These results demonstrate that it is ionization that results in the difference between the two models.

关键词： high-order Kerr model plasma defocusing filamentation

Field-free orientation of diatomic molecule via the linearly polarized resonant pulses

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Chinese Physics B 2015年第10期24卷 213-217页

作者：李苏宇郭福明王俊杨玉军金明星 Institute of Atomic and Molecular Physics Jilin University Jilin Provincial Key Laboratory of Applied Atomic and Molecular Spectroscopy Jilin University

We propose a scheme to coherently control the field-free orientation of NO molecule whose rotational temperature is above 0 K. It is found that the maximum molecular orientation is affected by two factors： one is the sum of the population of M = 0 rotational states and the other is their distribution, however, their distribution plays a much more significant role in molecular orientation than the sum of their population. By adopting a series of linearly polarized pulses resonant with the rotational states, the distribution of M = 0 rotational states is well rearranged. Though the number of pulses used is small, a relatively high orientation degree can be obtained. This scheme provides a promising approach to the achievement of a good orientation effect.

关键词： orientation diatomic molecule linearly polarized pulses coherent control

Screening For Language Disorders in Primary Care Settings

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中国儿童保健杂志 2011年第10期19卷 873-875页

作者： Mark D. Simms MD, MPH jin xing-ming Professor Department of Pediatrics Medical College of Wisconsin Medical Director Child Development Center Children's Hospital of Wisconsin Milwaukee Wisconsin USA Professor Shanghai Jiaotong Medical College Department of Development & behaviorShanghai Children's Medical Center Shanghai 200092 China

The acquisition of language ability is one of the most important milestones in early child *** ability to communicate with others extends beyond the use of spoken words and includes tone of voice,facial expression,

关键词： language disorders language development pri mary care

Umbilical Cord Blood Lead Levels in Shanghai, China

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Biomedical and Environmental Sciences 1997年第1期10卷 38-46页

作者： SHEN XIAO-ming YAN CHONG-HUAI GUO DI WU SHENG-MEI LI REN-QIU HUANG HONG AO LI-ming ZHOU JIAN-DE HONG ZHAO-YI XU JI-DE jin xing-ming AND TANG JUN-ming (Division of Childhood Lead Poisoning Prevention, Shanghai Institute for Pediatric Rese Division of Childhood Lead Poisoning Prevention Shanghai Institute for Pediatric Research Shanghai Second Medical University China. xmshen@***

This study was designed to determine the cord blood lead (BPb) levels of babies born in one urban area of Shanghai, and to preliminarily identify the demographic, social environment and prenatal factors which have an effect on the cord BPb concentrations. From August to November 1993, umbilical cord blood samples were obtained from 605 live newborns in the Yangpu Maternal and Child Hospital. 257 samples were excluded from measurement because of clotting. In 348 cord samples, the geometric mean of cord BPb levels was 9. 2μg/dl, with a 95 % confidence interval of the mean 8. 86-9. 54 (μg/dl). 142 babies (40. 8 % ) had cord BPb levels of 10μg/dl or greater. As a result of this high percentage of newborns with BPb levels equal to or greater than 10 μg/dl, we estimate that each year in the Shanghal City about 60,000 newborns are at risk for developing neuropsychological deficiencies caused by maternal lead exposure during pregnancy. To investigate the factors affecting cord blood levels, the subjects with levels greater than the 70th percentile (10. 7μg/dl) (n = 104) and less than the 3oth percentile (7. 4μg/dl) (n = 104) were selected to compare the demographic, environ ment and prenatal medical history. Increased BPb levels at birth were associated with maternal passive smoking, a family member being occupationally exposed to lead, proximity to major traffic way, household coal combustion, neighborhood coal combustion, low level of meternal occupations, and the increasing occurrence of having the high lead foodstuff pidan (preserved duck egg) during pregnancy. We conclude that prenatal lead exposure has become an impor tant health issue for young children in Shanghai

关键词： In Umbilical Cord Blood Lead Levels in Shanghai China

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纸机系统中的微生物问题及控制

中国造纸 2010年第2期29卷 61-68页

作者：金星明北京施澳德瑞科技有限公司北京100053

介绍了纸机系统中常见的微生物以及由此所引发的问题,对纸机系统中影响微生物生长的因素和微生物的测试方法以及如何合理控制系统中的微生物问题进行了阐述;并简单介绍了当前国外先进微生物黏泥的控制技术及发展方向。

关键词：纸机系统白水封闭循环微生物杀菌防腐剂检测

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语言样本分析在临床应用的可行性研究

上海交通大学学报（医学版） 2009年第7期29卷 772-774,793页

作者：金志娟金星明上海交通大学医学院上海儿童医学中心发育行为儿科上海市环境与儿童健康重点实验室上海200127

目的探讨用语言样本分析评估儿童语言发育水平的可行性,为语言样本分析应用于临床提供参考资料。方法以50名4～6岁儿童为研究对象,计算每名儿童20min内语言样本的平均句子长度(MLU)和词汇广度(D),并与年龄、韦克斯勒学龄前和学龄初期智... 详细信息

目的探讨用语言样本分析评估儿童语言发育水平的可行性,为语言样本分析应用于临床提供参考资料。方法以50名4～6岁儿童为研究对象,计算每名儿童20min内语言样本的平均句子长度(MLU)和词汇广度(D),并与年龄、韦克斯勒学龄前和学龄初期智力量表(WPPSI)及图片词汇测试(PPVT)结果进行相关分析;采用折半信度分析法,即分别计算并比较语言样本前100句和后100句的MLU值以及基于样本奇数词和偶数词的D值进行语言样本指标的内部信度分析。结果MLU值和D值与年龄呈正相关;MLU值、D值、年龄、语言智商(VIQ)和PPVT智商(PPVT-IQ)5个指标之间两两比较,除VIQ与年龄无相关性(P>0.05)外,其余均呈正相关(P<0.05或P≤0.01);MLU前100与MLU后100以及D奇与D偶呈现高度相关(均P=0.000)。结论语言样本分析能够反映4～6岁儿童的语言发育水平。

关键词：平均句子长度词汇广度标准化测试语言样本分析