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Negative Drive of γ Deformation in Rapidly Rotating N=88,90 Nuclei

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Chinese journal of nuclear physics 1994年第1期16卷 77-84页

作者： Chen, Yongshou Riedinger, l.l. China Inst of Atomic Energy Beijing China

In the N=88,90 region,a strong negative drive of γ deformation is generatedby the second lowest positive signature vi13/2 quasiparticle *** contrast,thelowest positive-parity and negative-parity orbitals in this region exhibit positive drivesin the γ deformation toward oblate *** one of these with the negativedrive orbital strengthens the collectivity for the side band configurations at very highspins.

关键词： Yrast rotational band Angular momenta Prolate-oblate barrier

西南天山榴辉岩相脉体记录的俯冲带多期流体作用

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岩石学报 2025年第1期41卷 183-197页

作者：吕佳阳李继磊王钟瑞马智佩中国科学院地质与地球物理研究所岩石圈演化与环境演变重点实验室北京100029 中国科学院大学地球与行星科学学院北京101408

俯冲带是全球最大的物质循环系统,控制着壳幔相互作用、岛弧岩浆作用、成矿物质聚集和全球元素循环等诸多重要的地质过程。俯冲带流体作为板片向上覆地幔楔进行物质传输的重要媒介,在上述地质过程中扮演着关键角色。基于岛弧火山岩地球... 详细信息

俯冲带是全球最大的物质循环系统,控制着壳幔相互作用、岛弧岩浆作用、成矿物质聚集和全球元素循环等诸多重要的地质过程。俯冲带流体作为板片向上覆地幔楔进行物质传输的重要媒介,在上述地质过程中扮演着关键角色。基于岛弧火山岩地球化学特征、高温高压实验、相平衡模拟,以及高压-超高压变质岩的研究,我们对俯冲带流体基本特征及其地球化学行为已经有了较为深刻的认识,然而,目前对俯冲带流体作用的复杂性,如多期流体作用,还缺少深入的理解。本文对西南天山高压-超高压变质带榴辉岩中一条含石英-绿帘石-铁白云石-硫化物的高压脉开展了详细的岩石学、地球化学研究。脉体中有绿辉石、铁白云石、金红石等特征高压矿物的产出,暗示其代表的流体作用发生于高压条件下。脉体与主岩榴辉岩界线截然,之间无蚀变带/过渡带/交代晕产出,说明主岩榴辉岩与迁移流体之间没有发生显著的水-岩交换反应。脉体矿物(如绿帘石、铁白云石、黄铁矿等)的多期生长特征及其成分差异研究揭示出至少三期流体作用。前两期流体作用均发生于高压条件下,特征如下:(1)两期流体分别以两期矿物组合(Ep^(1)-Dol^(1)-Py^(1)组合以及Ep^(2)-Dol^(2)-Py^(2)组合)为代表,在第二期流体作用下,第一期流体沉淀的矿物(如Dol^(1)等)发生了明显的溶解-再沉淀作用;(2)两期流体性质均以富Ca、Si,含C_(2)、S为特征,第一期流体较第二期流体富Fe贫Mg,富Ni贫Co,富轻稀土元素(lREE);(3)两期黄铁矿的δ^(34)S值分别为-8‰和-5‰,暗示这两期流体均主要来源于俯冲沉积物,且第二期流体可能有更多俯冲洋壳或蛇纹岩脱水流体的参与;(4)两期流体作用下,碳酸盐矿物和硫化物显示出耦合共生的特点,暗示C、S在流体作用下可能具有协同演化(如溶解-迁移-沉淀)的关系。第三期流体作用以绿帘石+铁白云石反应生成方解石+绿泥石、绿帘石边部(与黄铁矿相邻处)发生成分改造为特征,流体作用发生在高压岩石折返的退变质阶段,记录了退变质流体的信息。本研究通过榴辉岩高压脉体中多期矿物生长的特征,揭示了俯冲带内多期流体作用,对深入理解俯冲带流体性质、流体来源、以及俯冲带关键挥发分元素的耦合演化信息,具有重要的科学意义。

关键词：西南天山榴辉岩高压脉体俯冲带流体多期流体作用

Resistance of stored bean varieties to Acanthoscelides obtectus （Coleoptera： Bruchidae）

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Insect Science 2008年第4期15卷 317-326页

作者： Edson l.l. Baldin Fernando M. lara Department of Plant Production-Faculty of Agronomic Sciences/Sao Paulo State University Botucatu Sao Paulo State Department of Plant Protection Faculty of Agranan and Veterinary Sciences / Sao Paulo State University Zip Code 14884-900 Jaboticabal Sao Paulo State Brazil

During bean seed storage, yield can be lost due to infestations of Acanthoscelides obtectus Say, the bean weevil. The use of resistant varieties has shown promising results in fighting these insects, reducing infestation levels and eliminating chemical residues from the beans. The expression of resistance to A. obtectus in bean varieties is frequently attributed to the presence of phytohemagglutinins, protease inhibitors and alpha-amylase, and especially to variants of the protein arcelin, which reduce the larval viability of these insects. To evaluate the effect of bean seed storage time on the resistance expression of bean varieties to A. obtectus, tests with seeds of three ages （freshly-harvested, 4-month-old, and 8-monthold） were conducted in the laboratory, using four commercial varieties： Carioca Pitoco, Ipa 6, Porrillo 70, Onix; four improved varieties containing arcelin protein： Arc. 1, Arc.2, Arc. 3, Arc.4; and three wild varieties also containing arcelin protein： ***, Arc.3S, and Arc. 5S. The Arc.5S, ***, and Arc.2 varieties expressed high antibiosis levels against the weevil; Arc.1 and Arc3S expressed the same mechanism, but at lower levels. The occurrence of oviposition non-preference was also observed in Arc.5S and Arc. 1S. The Arc.3 and Arc. 4 varieties expressed low feeding non-preference levels against A. obtectus. The expression of resistance in arcelin-bearing, wild or improved varieties was affected during the storage of seeds, and was high under some parameters but low in others. The results showed that addition of chemical resistance factors such as protein arcelin via genetic breeding may be beneficial in improving the performance of bean crops.

关键词： antibiosis antixenosis bean weevil host plant resistance Phaseolus vulgaris

long-Time Shoreline Monitoring of the Vellar Estuarine Complex,Southeast Coast of India:Using Multispectral Satellite Data

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Journal of Earth Science 2012年第6期23卷 900-907页

作者： l Senthilnathan E P Nobi T Thangaradjou l Kannan Centre of Advanced Study in Marine Biology Faculty of Marine SciencesAnnamalai UniversityParangipettai-608502TamilnaduIndia

The present study was carried out to track the path of Vellar estuary over a period of 38 years （1970-2008） and also to detect the impact of tsunami on estuarine complex of the Vellar estuary. Visual interpretation techniques were employed by using muitispectral data of landsat TM （1991） and IRS-P6 lISS III （2004, 2006, and 2008） to delineate shoreline changes in the VeUar estuarine complex. Results clearly revealed the changes that occurred along the estuarine path over the period, and severe erosion was noticed in the seaward side of the MGR Thittu and accretion, along the estuarine mouth. It is also visible that there is clear river path shift in the river course. Although the sandbar formation was seen with only little morphologic modification up to 2004, the Indian Ocean tsunami that struck this coast （26 December, 2004） distorted the sandbar of the Vellar estuarine mouth; however, the 2006 satel- lite images confirmed that the sandbar was formed again to its original structure as that of before the tsunami.

关键词： estuary geomorphology IRS-P6 lISS III shoreline tsunami India.

A Baby Pterodactyloid Pterosaur from the Yixian Formation of Ningcheng,Inner Mongolia,China

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Acta Geologica Sinica(English Edition) 2009年第1期83卷 1-8页

作者： lü Junchang Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China

A new baby pterodactyloid pterosaur with soft tissue preserved, Ningchengopterus liuae gen. et sp. nov., is erected based on a nearly complete skeleton with a skull. It was characterized by the skull, slightly longer than the combined length of the dorsal and sacral vertebrae; 50 teeth （including upper and lower jaws）; short mid-cervical vertebrae; the humerus and the scapula, equal to that of the wing metacarpal in length; the ulna and the femur, equal to that of the first and third wing phalanx in length, respectively. The similar ratio of the wing phalanx 2 to wing phalanx 1 of Ningchengopterus and Eosipterus implies that Ningchengopterus may be close to the ctenochasmatid pterosaur. However, it may also imply that the isometrically growing of the first two wing phalanges exists among some pterosaurs.

关键词： Ningchengopterus Yixian Formation Ningcheng Inner Mongolia China

Influence of alloy element partitioning on strength of primary α phase in Ti-6Al-4V alloy

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Journal of Materials Science & Technology 2018年第5期34卷 782-787页

作者： l.R.Zeng H.l.Chen X.li l.M.lei G.P.Zhang Shenyang National laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China University of Chinese Academy of Sciences Beijing 100049 China School of Materials Science and Engineering University of Science and Technology of China Shenyang 110016 China AVIC Commercial Aircraft Engine Co.LTD Shanghai 200241 China

The partitioning effect of Al（α-phase stabilizer） and V elements（β-phase stabilizer） on strength of the primary α phases in the α/β Ti-6 Al-4 V alloy with the bimodal microstructure was *** was found that partitioning of Al and V elements took place in the Ti-6 Al-4 V alloy during the recrystallization process,leading to the variation of the content of Al and V elements in the primary α phases with changing the volume fraction of the primary α *** tests reveal a general trend that the strength of the primary α phases increases with decreasing the volume fraction of the primary α phases,and such trend is independent on the loading direction relative to the c-axis of the α *** enhanced strength is attributed to the increase of the content of Al element in the primary α phase,but it is not dominated evidently by the change of the V *** solid solution strengthening contributed from both the elastic strain introduced by the solute atoms and the variation of the density of states was estimated theoretically.

关键词： Ti-6Al-4V Nanoindentation Strength Alloy element partitioning Crystallographic orientation

Progress in the study of tectophysicochemistry

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Chinese Science Bulletin 2003年第11期48卷 1069-1079页

作者： lü Guxian Institute of Geomechanics Chinese Academy of Geological Sciences

Tectophysicochemistry is a research area that deals with the interrelations between physical and chemical changes of crustal materials caused by tectonism. A given tectonic force may be resolved into two parts: homogeneous stress and differential stress. Homogeneous stress refers to isotopic pressure, which is superimposed on the original pressure and affects the equilibrium of various chemical reactions. It is also a factor that influences petrogenesis, metallogenesis and metamorphism. Differential stress is commonly produced when external forces act on a given solid body. It may cause deformation of crustal materials and generate various kinds of structural features. Tectophysicochemistry pays special attention to pressure, temperature and other physicochemical conditions produced or induced by tectonism and studies the influences of additional tectonic parameters on various chemical equilibria, so it gradually develops into an independent area of science.

关键词：地壳运动地壳物质物理变化化学变化构造物理化学岩石形成构造运动

A New Boreopterid Pterodactyloid Pterosaur from the Early Cretaceous Yixian Formation of liaoning Province,Northeastern China

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Acta Geologica Sinica(English Edition) 2010年第2期84卷 241-246页

作者： lü Junchang Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China

A new boreopterid pterosaur： Zhenyuanopterus longirostris gen. et sp. nov. from the Yixian Formation of western liaoning is erected, based on the complete skeleton with a skull and lower jaws preserved. It is characterized by： a large boreopterid pterosaur with a high number of teeth, where the anterior teeth are much larger than posterior ones; the length of the dorsal ＋ sacral vertebrae is nearly half the length of the skull; ratio of the length of the humerus to metacarpal IV is approximately 91% and the, humerus, femur and third wing phalanx are all equal in length and the feet are specially small. It represents the largest boroepterid pterosaur discovered from western liaoning and its surrounding areas so far

关键词： Zhenyuanopterus Boroepteridae Ornithocheiroidae Yixian Formation western liaoning

Optimization of hydrothermal pretreatment for co-utilization of xylose and glucose of cassava anaerobic residue for producing ethanol

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Chinese Journal of Chemical Engineering 2019年第4期27卷 920-927页

作者： Huisheng lü Jinyi Zhou Jiatao liu Chunliu lü Feng lian Yonghui li Key laboratory for Green Chemical Technology of Ministry of Education R&D Center for Petrochemical Technology Tianjin University Tianjin 300072 China Collaborative Innovation Center of Chemical Science and Engineering Tianjin 300072 China

The development of a process that could recover biofuel from industrial cellulose waste can not only reduce the negative environmental impacts by using fossil fuels, but also bring a green idea for the waste’s disposing. In this study, hydrothermal pretreatment was optimized for cassava anaerobic residue, a cellulosic waste from cassava ethanol industry, to co-utilize xylose and glucose for producing bioethanol. The effect of the main pretreatment conditions, namely, temperature, solid content and time, was explored for the highest recovery of xylose in prehydrolysate and glucose in enzymatic hydrolysate. The single factor experiment results showed that the conditions for maximum xylose recovery in prehydrolysate and glucose recovery in enzymatic hydrolysate were 60℃, 75 min, 10% solids and 160℃, 75 min, 10% solids, respectively. Whereafter, response surface methodology(RSM) was applied to further optimize the pretreatment conditions for the maximum theoretical ethanol production through utilizing both xylose and glucose. A treatment at 163℃, for 59 min and with 9.5%solids was found optimal, with the highest ethanol production of 20.2 mg·g^-1 raw material. Furthermore, in order to assess the impacts of the pretreatment on cassava anaerobic residue, the changes in crystallinity and morphology for untreated and pretreated solids were investigated.

关键词： Waste treatment Biofuel Hydrothermal Cassava anaerobic residue Co-utilization Response surface methodology