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Vegetation and climate change during Marine Isotope Stage 3 in China

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Chinese Science Bulletin 2014年第33期59卷 4444-4455页

作者： Yan Zhao Zicheng Yu Ulrike Herzschuh Bao Yang Hui Zhao Keyan Fang Huan Li Quan Li Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Department of Earth and Environmental Sciences Lehigh University Alfred Wegner Institute for Polar and Marine Research Cold and Arid Regions Environment and Engineering Research Institute Chinese Academy of Sciences Fujian Normal university Research School of Arid Environment and Climate Change Lanzhou University

Fossil pollen records from 45 sites across China were evaluated and synthesized to document vegetation and climate change during Marine Isotope Stage 3(MIS 3)at 60–27 ka and to understand the large-scale *** MIS3, vegetation type was dominantly forest in eastern China, forest steppe/meadow in the north and Tibetan Plateau, and steppe desert in northwestern arid China. We developed a semi-quantitative vegetation index to reflect change in plant abundance(by inferring the general climate conditions), with a vegetation score from 1to 3 based on the different vegetation types inferred from pollen data at individual sites at intervals of 2,000 *** reconstructed vegetation index shows higher values during MIS 3, especially during the period 53–40 ka, than at the Last Glacial Maximum. Our results also suggest that climate on the basis of vegetation change was cooler and drier during MIS 3 than during the Holocene optimum;however, MIS 3 vegetation was probably similar to modern vegetation. The close relationship between vegetation change, insolation and Asian summer monsoon strength suggests that climate variations, probably in both temperature and precipitation, are the primary drivers of regional vegetation change. Additional well-dated, high-resolution palaeoclimate records from many locations across China will be needed to understand the vegetation change and climate forcings on millennial and centennial scales within MIS 3.

关键词：深海氧同位素植被类型气候变化中国海洋草原化荒漠植被变化中国东部地区森林草原

The Impacts of State Ownership on Information Asymmetry:Evidence from an Emerging Market

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China Journal of Accounting Research 2010年第Z1期3卷 13-50页

作者： Jongmoo Jay Choi Heibatollah Sami Haiyan Zhou Department of Finance Fox School of BusinessTemple University Department of Accounting Lehigh University Department of Accounting and Business Law University of Texas-Pan American

This study examines the effect of corporate ownership on information asymmetry as measured by bid-ask spread in the emerging markets of China. Government ownership has significant and positive impacts on bid-ask spread during the period 1995-2000, but disappears afterward during 2001-2003. The finding that state ownership raised bid-ask spread in the early period is consistent with recent studies on emerging markets including China, which indicate that firms with higher state ownership tend to have a greater deviation between cash flow rights and control rights(eg, Wei et al., 2005). This implies that lower state ownership is associated with lower information asymmetry in the market, an economic consequence of significant economic reform and privatization regarding the market microstructure. However, with more active control transfers andemergence of private controlling shareholders, regulatory changes in ownership structure and corporate governance mechanisms, and thus an improved legal and institutional environment, the link between the government ownership and information asymmetry turns to be insignificant in the later period. These results have important implications for transparency and information disclosure policies as well as privatization in emerging markets.

关键词： Bid-ask spread Information asymmetry Transparency Adverse selection Government(State) ownership Foreign ownership Emerging market(China)

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纳米金属铁降解有机卤化物的研究进展

化学进展 2006年第1期18卷 93-99页

作者：程荣王建龙张伟贤清华大学核能与新能源技术研究院环境技术研究室北京100084 Department of Civil and Environmental Engineering Lehigh University Bethlehem

有机卤化物是一种毒性强、难生物降解的环境污染物,传统处理技术存在着降解不完全、效率低等不足。纳米技术的发展给有机卤化物的处理带来了一种新的颇具潜力的方法,即应用纳米金属/双金属颗粒对有机卤化物进行脱卤。目前,以Fe(Ⅱ)和Fe(... 详细信息

有机卤化物是一种毒性强、难生物降解的环境污染物,传统处理技术存在着降解不完全、效率低等不足。纳米技术的发展给有机卤化物的处理带来了一种新的颇具潜力的方法,即应用纳米金属/双金属颗粒对有机卤化物进行脱卤。目前,以Fe(Ⅱ)和Fe(Ⅲ)等常见原料合成纳米铁颗粒的技术已经成熟,纳米颗粒对有机卤化物也显示出高效的降解性能。更重要的是,其可灵活应用于地下水和土壤的原位和异位修复,尤其适用于原位修复。本文综述了纳米铁颗粒降解有机卤化物的研究进展,包括纳米铁颗粒的合成与修饰,降解效能、降解机理、降解动力学、示范工程等,以及发展前景和今后的研究方向。

关键词：纳米颗粒有机卤化物铁双金属

Inter-Cell Interference Management in WiMAX Downlinks by A Stackelberg Game between BSs

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Inter-Cell Interference Management in WiMAX Downlinks by A S...

The role of cross-listing,foreign ownership and state ownership in dividend policy in an emerging market

2008 IEEE International Conference on Communications(ICC 2008)

作者： Koon Hoo Teo Shalinee Kishore Mitsubishi Electric Research Laboratories CambridgeMA 02139 Electrical and Computer Engineering Lehigh UniversityBethlehemPA 18015

We develop a game theoretic framework for effective and adaptive inter-cell interference management in the OFDMA-based WiMAX/3GPP-LTE *** approach requires no fixed spectrum planning beforehand and does not affect the spectrum usage for users that are not subject to inter-cell *** on the handoff mechanisms in WiMAX systems,we also examine means of categorizing users who are,or are not,subject to potential *** optimization opportunities for BSs are identified and *** interactions between BSs are modeled by a Stackelberg game in which BSs can make intelligent and rational decisions to reduce interference with minimum optimization *** algorithm to attain stable Nash Equilibrium is investigated and the behaviors of BSs with different preferences in the game are examined.

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China Journal of Accounting Research 2012年第3期5卷 199-216页

作者： Kevin C.K.Lam Heibatollah Sami Haiyan Zhou School of Accountancy The Chinese University of Hong Kong Department of Accounting Lehigh University Department of Accounting and Business Law College of Business AdministrationThe University of Texas -Pan American

In this paper, we investigate if dividend policy is influenced by ownership *** the dividend literature, dividends have a signaling role regarding agency costs, such that dividends may diminish insider conflicts(reduce free cash flow) or may be used to extract cash from firms(tunneling effect)- which could be predominant in emerging markets. We expect firms with foreign ownership and those that are listed in overseas markets to have different dividend policies and practices than those that are not, and firms with more state ownership and less individual ownership to be more likely to pay cash dividends and less likely to pay stock dividends. Using firms from an emerging economy(China), we examine whether these effects exist in corporate dividend policy and practice. We find that both foreign ownership and cross-listing have significant negative effects on cash dividends, consistent with the signaling effect and the notion of reduced tunneling activities for firms with the ability to raise capital from outside of China. Consistent with the tunneling effect, we find that firms with higher state ownership tend to pay higher cash dividends and lower stock dividends, while the opposite is true for public(individual) *** analysis shows that foreign ownership mediates the effect of state ownership on dividend policy. Our results have significant implications for researchers, investors, policy makers and regulators in emerging markets.

关键词： Agency problems Corporate governance Cash dividends Stock dividends Ownership structure Cross listings Emerging markets

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非平衡态/不可逆过程的热力学理论(Ⅰ)

力学进展 1989年第2期19卷 158-171页

作者：薛昌明卢天健美国lehigh大学断裂与固体力学研究所香港大学机械工程系

一切物理过程或现象都具有瞬时性和不可逆性,迄今为止的所有热力学和连续介质力学理论皆因为或多或少的理想化假设而不能对这些过程或现象的物理本质作出精确的客观描述。新理论与传统理论的根本分歧在于把热形式的变化和机械形式的变... 详细信息

一切物理过程或现象都具有瞬时性和不可逆性,迄今为止的所有热力学和连续介质力学理论皆因为或多或少的理想化假设而不能对这些过程或现象的物理本质作出精确的客观描述。新理论与传统理论的根本分歧在于把热形式的变化和机械形式的变化视作共同存在于同一物理过程或现象中互相耦合的两个方面,它们的有机组合则通过传统的热量概念的舍弃而得到实现;耗散能密度和有效能密度被定义为互相排斥的两个独立变量,对物体转动、变形以及体积变化的描述被统一起来,物理过程的不可逆本质成为新理论的固有特征。新理论不需要对材料的本构方程作任何预先假设。相反,这些本构方程将在求解过程中自动地推解出来,只需要输入材料变形的初始斜率及有关加载历史的数据。在新理论中,体积能密度和表面能密度可以相互转换,或者说体积相对于面积的变化是有限值而不是如传统理论中所假设的那样,在取极限过程中趋近于零而忽略不计,也正是该假设导致在传统理论中热变化和机械变化的相互独立(解耦)。新理论保留了非线性和有限变形,从而可以通过设置恰当的力或位移边界条件来求解任何边值问题。平衡态/不可逆过程被证明具有唯一解,非平衡态/不可逆过程则被证明具有确定的极限解且受到平衡态/不可逆过程的限界。等能面的存在性定理为?

关键词：非平衡态不可逆过程热力学

利用焊接过程声发射信息进行焊缝跟踪控制的可行性研究

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镇江船舶学院学报 1991年第1期5卷 6-10页

作者：蒋鹏飞 John D Wood 镇江船舶学院 lehigh university

本文研究了钢板上缝隙对声发射波传播的影响,当声发射源位于缝隙顶端附近时,缝隙的存在明显影响声发射波的传播,这种缝隙效应能被利用于开发一种新的焊缝跟踪控制方法。

关键词：声发射焊接焊缝跟踪装置

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非平衡态/不可逆过程的热力学理论(Ⅱ)

力学进展 1989年第3期19卷 304-319页

作者：薛昌明卢天健美国lehigh大学断裂与固体力学研究所香港大学机械工程系

7 解的唯一性如果不考虑非平衡态和不可逆性,则等能密度理论中的基本命题与经典弹性理论中的在形式上完全相同。无论整个系统的动能是大还是小,图6中(sumform)_o上的面力T_i和在(sumform)_c和在的位移u_i将始终在空间坐标系x_i和时刻i... 详细信息

7 解的唯一性如果不考虑非平衡态和不可逆性,则等能密度理论中的基本命题与经典弹性理论中的在形式上完全相同。无论整个系统的动能是大还是小,图6中(sumform)_o上的面力T_i和在(sumform)_c和在的位移u_i将始终在空间坐标系x_i和时刻i下给出。与一般力学中相同,必须知道有关位移u_i及其时间导数的初始条件。它们的影响则可通过(38)和(39)向等能面转化。

关键词：非平衡态不可逆过程热力学

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纳米级无机聚钼酸盐“二级有序聚集体”

物理化学学报 2006年第10期22卷 1300-1304页

作者：贾祥凤范大伟唐培芹郝京诚马丽英刘天波山东大学胶体与界面化学教育部重点实验室滨洲医学院基础部 Department of Chemistry Lehigh University Bethlehem Pennsylvania 18015 USA

介绍了纳米级水溶性无机聚钼酸盐分子的逐步生长合成,对近年来水溶液中纳米级无机聚钼酸盐分子的奇特自聚集行为进行了简述,从两亲分子“有序聚集体”概念的角度,提出了水溶性纳米级无机聚钼酸盐“二级有序聚集体”的概念.

关键词：二级有序聚集体纳米级聚钼酸盐囊泡两亲分子激光光散射