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飞秒激光等离子体中电子热传导现象的数值模拟

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强激光与粒子束 2014年第9期26卷 172-176页

作者：阿不都热苏力地里夏提艾尔肯新疆大学物理科学与技术学院乌鲁木齐830046

采用相对论电磁粒子模拟程序研究了飞秒激光等离子体相互作用中产生的电流密度、电场和自生磁场的发展演化过程。介绍了电子的非局域热输运的基本特性以及激光加热过程中温度烧蚀前沿稠密等离子体子区的预热效应、临界面附近的限流效应... 详细信息

采用相对论电磁粒子模拟程序研究了飞秒激光等离子体相互作用中产生的电流密度、电场和自生磁场的发展演化过程。介绍了电子的非局域热输运的基本特性以及激光加热过程中温度烧蚀前沿稠密等离子体子区的预热效应、临界面附近的限流效应,以及冕区的反扩散与限流效应,得到了经典Spitzer-Harm理论描述的电子热传导随自生磁场的演化情形。数值模拟表明:在线性强激光作用下,由于电子初始时刻的无规则热运动,在等离子体上激发电磁不稳定性,而不稳定性激发的强电磁场使电子束在非常短的距离内沉积能量,同时对在激光有质动力推开电子时形成的超热电子能量输运产生抑制作用。

关键词：电流密度电场磁场饱和自生磁场电子热传导粒子模拟法

Mixed symmetry states and isospin excitation in N = z nucleus ^(52)Fe

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Science China(physics,Mechanics & Astronomy) 2008年第12期51卷 1845-1852页

作者： zHANG JinFu↑, lü liJun, BAI HongBo & lIANG Mingzhi Department of physics, Chifeng University, Chifeng 024001, China Department of physics Chifeng University Chifeng China

the interacting boson model with isospin (IBM-3) was applied to study the band structure and electromagnetic transition properties of the low-lying states in the even-even N = z nucleus 52Fe. the isospin excitation states with t = 0, 1 and 2 were identified, and compared with the available data. the study shows that the 2+3 state is the lowest mixed symmetry state in 52Fe. the excitation energy of the second 0+2 state with t = 0 in nucleus 52Fe was identified. the model calculations with the data show a reasonably good agreement.

关键词： energy level isospin mixed symmetry states electromagnetic transitions

trace Elements in leccinum scabrum Mushrooms and topsoils from K odzka Dale in Sudety Mountains, poland

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Journal of Mountain Science 2013年第4期10卷 621-627页

作者： zHANG Dan zHANG Yu MOrAWSKA Ewa BIElAWSKI leszek KrASINSKA Grazyna DrEWNOWSKA ma gorzata pANKAVEC Sviatlana SzYmaNSKA Karolina FAlANDYSz Jerzy Key laboratory of Mountain Environmental Diversity & Control Institute of Mountain Hazards and Environment Chinese Academy of Sciences Institute of Environmental Sciences & public Health University of Gdańsk 19 Sobieskiego Str.80-952 Gdańsk Poland

In the current study, we determined concentrations and transfer rates of Ag, Al, Ba, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, pb, p, rb, Sr and zn to Brown Birch Scaber Stalks （leccinum scabrum） mushrooms emerged in the area of Sudety Mountains （Sudetes） in poland. Fruiting bodies and topsoil samples beneath l. scabrum were collected form the Ktodzka Dale. the trace elements were determined using validated method and inductively coupled plasma - atomic emission spectroscopy （ICp-AES） for final measurement. Mushrooms contained Ag, Cr, Hg, Co, Ni and Sr at 〈 1.0μg/g dry weight; Ba and pb at -1.0μg/g dw; Cd at 〈 5μpg/g dw; Cu and Mn at 〉 10 μg/g dw; Al and Ca at -100μg/g dw; Fe, Na, rb and zn at lOO to 500μg/g dw, Mg at -1.000μg/g dw; p at -5,000 μg/g dw and K at -30,000 μg/g dw. Ca, Mn and Ni were nearly equally distributed between stipes and caps; stipes compared to caps were enriched in Ba, Na and Sr, while caps were enriched in Ag, Al, Cd, Co, Cr, Cu, Fe, K, p, pb, rb and zn. the values of bioconcentration factor （BCF） varied highly depending on chemical element and were 〉1 for Ag, Cd, Cu, K, Mg, Na, p, rb and zn, while 〈1 for A1, Ba, Ca, Co, Cr, Fe, Mn, Ni, pb and Sr. topsoil showed elevated content of lead and mean concentration was 99 ± 32 μg/g dw, while cadmium was at 0.41 ± 0.15 and those two highly toxic to human elements occurred in edible caps of l. scabrum at 4.5 ± 2.2 and 2.9 ± 2.0 μg/g dw, respectively.

关键词： Food Fungi Metallic elements Soil Sudetes Wild food

DEFOrmatION FEAtUrES OF maNtlE XENOlItHS AlONG tANlU FAUlt zONE AND tHEIr GEOlOGICAl IMplICAtIONS

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地震地质 1992年第4期 297-303页

作者： lin Chuanyong Shi lanbin(Institute of Geology, SSB, Beijing 100029)J. V. ross J. K. russell(Department of Geological Sciences, the University of British Columbia, Vancouver, V6t 1z4 Canada)

the mantle xenoliths from 6 localities along and eastward of the active tanlu fault zone are mostly spinel lherzolite, with few exception of wehrlite. the textures are variable from initial porphyroclastic through granuloblaslic to mylonitic. the analysis of mineral equilibria has revealed that these xenoliths attained to a good state of *** equilibrium temperatures determined by using 3 different methods are 700-1000℃, while the pressures have been estimated to be in a range of 0.9-2.5 Gpa. the constructed geotherms have shown that most of the points lie above the theorectical continental geotherm, indicating the existence of an upper.ma.tle diapir associated with tectonic extension known to occur in thus region. the low temperature of mylonitic xenoliths indicates the existence of an active shear zone just below the crust. It might control the development of seismically active zone in this region.

关键词： tanlu fault zone Upper.ma.tle mantle xenolith texture of xenolith palaeogeotherm

Analysis of prlr and BF Genotypes Associated with litter Size in Beijing Black pig population

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Agricultural Sciences in China 2008年第11期7卷 1374-1378页

作者： WANG Xing-ping WANG li-xian lUO rENG zhuo-ma SUN Shi-duo Institute of Animal Science Chinese Academy of Agricultural Sciences Beijing 100193 P.R. China Department of life Sciences ＆ technology Xinxiang Medicine University Xinxiang 453003 P.R.China College of Animal Science and technology Northwest A ＆ F University Yangling 712100 P.R.China

this study is aimed at using the DNA mutations in the prolactin receptor （prlr） and properdin （BF） genes to determine associations between the genotype and litter size in the Beijing Black pig population. A total of 321 Beijing Black pig sows were genotyped using the polymerase chain reaction-restriction fragment length polymorphism （pCr-rFlp） method, with the Alu I and Sma I for prlr and BF genes, respectively. two different alleles of prlr and BF genes were identified： allele A （0.25） and B （0.75） of the prlr gene, allele A （0.13） and B （0.86） of the BF gene. the association analysis between the genotypes and the litter size were estimated with the method of the general linear model. the analysis results of prlr showed that in first parity, sows with genotype AA had a larger litter size than sows with genotype AB and BB, but the difference was statistically not significant. In later parities, statistically significant （p 〈 0.05） differences were seen between sows with genotypes AA and AB, and BB of the prlr gene. the associated analysis results between genotypes and litter size （total number born, tNB, and number born alive, NBA） showed that there were no significant differences in the first parity sows with different genotypes of the BF gene, but significant differences appeared in NBA between the sows of genotypes AB and BB, in later parity, for which significantly higher values were observed in the offspring of heterozygotes. Considering the consistent genotypic effect on the litter size of both sows in first parity and later parity, it was concluded that the locus of the prlr gene, digested with Alu I, could be the gene maker for the litter size in Beijing Black pigs.

关键词： prolactin receptor properdin litter size pig

Chaotic particle swarm optimization for non-circular critical slip surface identification in slope stability analysis

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Chaotic particle swarm optimization for non-circular critica...

A novel electrocatalyst for oxygen reduction reaction based on pyrolyzed non-noble metal chelate

the International Young Scholars’ Symposium on rock Mechanics

作者： H.B.zhao z.S.zou z.l.ru School of Civil Engineering Henan polytechnic University Jiaozuo China

＜正＞Slope stability problems are usually analyzed by limit equilibrium methods（lEM）.A number of existing methods based on finding the circular critical slip surface for homogeneous soils are not suitable for slope stability analysis due to the fact that the slip surfaces are noncircular for layered *** location of critical slip surface of a general slope is hardly an objective function of the factor of safety because its general non-convex and multiple *** emerged techniques such as particle swarm optimization （pSO）have shown advantages in addressing this ***,the performance of simple pSO is usually dependent on its *** incorporating chaos mapping into the particle swarm optimization algorithm, an updated pSO method addressing the critical slip surface locating problems is proposed in this *** performance of the presented chaotic pSO is little affected by its parameters,and is more *** with Spencer method,the new method has been examined and tested on two classic problems for searching the non-circular critical slip *** results indicate that the new approach can solve the problem with faster convergence rate and better precision.

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A novel electrocatalyst for oxygen reduction reaction based ...

phytochemical Analysis of ziziphus jujuba leaves in Six Cultivars at the Whole life Stage by High performance liquid Chromatography

第九届全国氢能学术会议

作者： H.J.zhang,z.F.ma,Q.z.Jiang,X.X.Yuan,Y.C.Hu,D.liu Shanghai Jiao tong University,China

＜正＞Finding a low-cost electrocatalyst for oxygen reduction reaction（Orr） is an important issue for the commercialization of pEMFCs,due to the higher loading of pt at the cathode as compared to the *** the present presentation,a new and promising non-noble metal cobalt-based electrocatalyst for Orr is prepared with sol-gel method from a carbon-supported

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Chemical research in Chinese Universities 2017年第5期33卷 702-708页

作者： CUI Xueqin ma zhongxiao BAI lu WU Yong GUO Sen lIU Qingchao zHANG li HO Chi-tang BAI Naisheng College of Chemical Engineering Department of Pharmaceutical Engineering Northwest University Xi'an 710069 P. R. China Department of Food Science Rutgers University New Brunswick New Jersey 08901 USA

leaves of ziziphus jujuba Mill.（z. jujuba） were used as a folk medicine to treat children suffering from typhoid fever, furuncle and ecthyma in China. the present study was to establish a high performance liquid chroma- tography-diode array detector（HplC-DAD） method for quality control of z. jujuba leaves. the validated method was applied to the simultaneous characterization and quantification of sixteen main constituents in thirty samples, which comprised the whole life stage of z. ]ujuba leaves from six cultivars in Yulin, Shannxi province, China. HplC fin- gerprint file of z. jujuba leaves was set up and the results indicate that the major constituents of z. jujuba leaves are （-）-catechin（1）, quercetin-3-O-robinobioside（3）, rutin（4） and quercetin-3-O-a-l-arabinosyl-（1---~2）-a-l-rhamnoside（6） with the total contents of the nine flavonoids in respective batch ranging from 18.52 mg/g to 39.51 mg/g. In addition, the contents of compounds depend on both the season and the cultivar. During ripening of z. jujuba leaves, flavo- noids of all the cultivars present a similar trend： initially decrease from 25th, Jun. to 5th, Aug., 2015, and then in- crease for a period of time, finally slightly fluctuate on 5th Oct. the highest contents of total flavonoids were regis- tered on 25th Jun., 2015. Different cultivars have 50%--90% variation on the content for the three classes of com- pounds. taken together, the results demonstrate that z. jujuba leaves have great potential to be a new health-promoting resource based on flavonoids and the best sampling time of them is in June.

关键词： Flavonoid High performance liquid chromatography-diode array detector(HplC-DAD) Quality control ziziphus jujuba leaf

Foot strike patterns and hind limb joint angles during running in Hadza hunter-gatherers

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Journal of Sport and Health Science 2014年第2期3卷 95-101,153+156页

作者： Herman pontzer Kelly Suchman David A.raichlen Brian M.Wood Audax z.p.mabulla Frank W.marlowe Department of Anthropology Hunter College City University of New York New York Consortium for Evolutionary primatology Evolutionary Anthropology Duke University School of Anthropology University of Arizona Department of Anthropology Yale University Department of Archeology University of Dar es Salaam Department of Archaeology and Anthropology University of Cambridge

Background:Investigations of running gait among barefoot and populations have revealed a diversity of foot strike behaviors,with some preferentially employing a rearfoot strike(rFS) as the foot touches down while others employ a midfoot strike(MFS) or forefoot strike(FFS).Here,we report foot strike behavior and joint angles among traditional Hadza hunter-gatherers living in Northern ***:Hadza adults(n = 26) and juveniles(n = 14) ran at a range of speeds(adults:mean 3.4 ± 0.7 m/s,juveniles:mean 3.2 ± 0.5 m/s) over an outdoor trackway while being recorded via high-speed digital *** strike type(*** FFS) and hind limb segment angles at foot strike were ***:Hadza men preferentially employed MFS(86.7%of men),while Hadza women and juveniles preferentially employed rFS(90.9%and85.7%of women and juveniles,respectively).No FFS was ***,the presence of footwear(sandals ***),and trial duration had no effect on foot strike ***:Unlike other habitually barefoot populations which prefer FFS while *** men preferred *** Hadza women and juveniles preferred *** and age differences in foot strike behavior among Hadza adults may reflect differences in running experience,with men learning to prefer MFS as they accumulate more running experience.

关键词： Barefoot Biomechanics Foot strike Foraging running