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二十一世纪的教育:初等教育展望

比较教育研究 1993年第5期 50-51页

作者： m.j.泰尔熊伟美国马里兰州尼吉利小学重庆钢铁专科学校基础部

美国各院校学生失去了对科学、工程的兴趣,在不久的将来,美国就会面临短缺成千上万的科学工作者的局面。为此,国家教委任命马里兰州教育专家露丝玛莉·j·泰尔组织一个科学教育委员会。要求此委员会对全国各所学校的科学课程结构进行评... 详细信息

美国各院校学生失去了对科学、工程的兴趣,在不久的将来,美国就会面临短缺成千上万的科学工作者的局面。为此,国家教委任命马里兰州教育专家露丝玛莉·j·泰尔组织一个科学教育委员会。要求此委员会对全国各所学校的科学课程结构进行评估和重新调整,并拿出几套可行的改革方案,使科学教育指导原则能适应社会的发展,并将此指导原则与现行课程结构挂起勾来。科学教育委员会的工作者作了大量的研究工作。

关键词：科学教育初等教育科学课程改革方案指导原则教育专家研究工作国家教委兴趣科学工作者

安徽巢湖地区下三叠统牙形石生物地层分带及其全球对比

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地球科学（中国地质大学学报） 2005年第5期30卷 623-634页

作者：赵来时童金南 Orchard m.j. 左景勋中国地质大学地质过程与矿产资源国家重点实验室湖北武汉430074 加拿大地质调查局中国科学院南京地质古生物研究所江苏南京210018

安徽巢湖地区早三叠世处于下扬子碳酸盐岩缓坡较深水区域,地层序列完整、清晰,各类化石是区域乃至全球最为丰富、序列最为完整的,是研究国际早三叠世年代地层最经典地区之一.对安徽巢湖平顶山西坡剖面、平顶山北坡剖面、马家山南剖面系... 详细信息

安徽巢湖地区早三叠世处于下扬子碳酸盐岩缓坡较深水区域,地层序列完整、清晰,各类化石是区域乃至全球最为丰富、序列最为完整的,是研究国际早三叠世年代地层最经典地区之一.对安徽巢湖平顶山西坡剖面、平顶山北坡剖面、马家山南剖面系统采样和精细的牙形石生物地层研究结果表明,下三叠统至少可以划分为8个牙形石带,建立了在华南具有代表性的下三叠统牙形石生物地层序列,自下而上为(1)Hindeodustypicalis带;(2)Neogondolellakrystyni-Neogondolellaplanata带;(3)Neospathoduskummeli带;(4)Neospathodusdieneri带;(5)Neospathoduswaageni带;(6)Neospathoduspingdingshanensis带;(7)Neospathodushomeri带;(8)Neospathodusanhuinensis带.并与世界其他地区同期地层进行精确对比,为建立下三叠统印度阶与奥伦尼克阶界线的全球层型(GSSP)提供可靠依据.

关键词：生物地层牙形石带下三叠统全球对比安徽巢湖

羟基自由基和醚进行气相反应时的基团反应活性

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物理化学学报 1989年第2期5卷 210-213页

作者：刘仁章 Wallington T.j. Dagaut P. Kurylo m.j. 国家标准和技术研究所化工中心化学动力学组

本文应用闪光光解共振荧光技术测量了OH自由基和乙二氧基甲烷气相反应的绝对速率常数,k=(1.68±0.16)×10^(-11)cm^3 molecule^(-1)s^(-1),统计分析求得误差为2σ。实验时系统总压力为25—50Torr(以Ar为稀释气体)。我们曾根据正烷基单... 详细信息

本文应用闪光光解共振荧光技术测量了OH自由基和乙二氧基甲烷气相反应的绝对速率常数,k=(1.68±0.16)×10^(-11)cm^3 molecule^(-1)s^(-1),统计分析求得误差为2σ。实验时系统总压力为25—50Torr(以Ar为稀释气体)。我们曾根据正烷基单醚的动力学测量结果来计算CH_3和CH_2的反应活性值。现发现此活性值此正烷烃对应值约大2倍,但能够精确地估算OH自由基与二乙氧基甲烷气相反应的速率常数。而且表明烷基链中次甲基的位置及数目对其反应活性贡献甚小。

关键词：羟基自由基醚气相反应反应活性

Unusual high-density and saline aqueous inclusions in ultrahigh pressure metamor- phic rocks from Sulu terrane in eastern China

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Chinese Science Bulletin 2003年第18期48卷 2018-2023页

作者： SHEN Kun ZHANG Zeming A.m.van den Kerkhof xiao Yilin XU Zhiqin j.Hoefs Institute of Geological Sciences of Shandong Jinan 250013China Institute of Geology CAGSBeijing 100037China Geoscience Center University GttingenGttingen 37077Germany

Primary high-density fluid inclusions were identified in garnet from ultrahigh pressure eclogite in the southern part of the Sulu terrane. They occur isolatedly or in cluster together with relatively low-density two-phase inclu-sions. The eutectic temperature of the inclusions is as low as ≤ -52℃. A bubble was nucleated in a liquid inclusion dur-ing the specific stage of cyclic cooling-heating runs, and the liquid-gas homogenization temperature was measured to be ≤-12.5℃. The composition of the inclusions modeled by the system CaCl2-NaCl-H2O, yields the fluid density of 1.27g/cm3 that corresponds to a pressure of ca. 2.4 GPa at thetemperature of peak eclogite-facies metamorphism, close tothe ultrahigh pressure metamorphic conditions. During theexhumation of the eclogite the inclusions reacted with thehost mineral, forming hydrous silicate minerals that resulted in lowering of the fluid density and its transformation to multi-phase inclusions.

关键词： ultrahigh pressure eclogite fluid inclusion microther-mometry isochore P-T path.

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齐河县保护地生姜高产栽培管理技术

长江蔬菜 2025年第1期 66-68页

作者：肖树涛齐河县潘店镇农业综合服务中心山东德州251125

生姜是我国重要特产蔬菜之一。主要介绍了齐河县生姜高产栽培管理技术,包括产地环境条件、品种选择、培育壮芽、整地施肥、播种、田间管理、收获等环节的操作要点,以供种植户参考。

关键词：生姜培育壮芽整地施肥播种田间管理

The role of oil futures intraday information on predicting US stock market volatility

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journal of management Science and Engineering 2021年第1期6卷 64-74页

作者： Yusui Tang xiao xiao m.I.m.Wahab Feng ma School of Economics&management Southwest Jiaotong UniversityChengduChina Department of mechanical and Industrial Engineering Ryerson UniversityTorontoCanada

This study investigates the role of oil futures price information on forecasting the US stock market volatility using the HAR ***-sample results indicate that oil futures intraday information is helpful to increase the ***,compared to the benchmark model,the proposed models improve their predictive ability with the help of oil futures realized *** particular,the multivariate HAR model outperforms the univariate ***,considering the contemporaneous connection is useful to predict the US stock market ***,these findings are consistent across a variety of robust checks.

关键词： Volatility forecasting The US stock market Oil market volatility Realized volatility DCC model

球形夸克-胶子等离子体演化源的π干涉学分析(英文)

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高能物理与核物理 2005年第1期29卷 46-49页

作者： Efaaf m.j. 张卫宁 Khaliliasr m. 金恩培刘亦铭哈尔滨工业大学物理系哈尔滨150006

本文对球形演化的夸克 -胶子等离子体膨胀源进行了 2π干涉学分析 .夸克 -胶子等离子体的演化由相对论流体力学和熵密度的物态方程描述 ,而 2πHanbury Brown Twiss (HBT)关联函数由量子几率振幅的路径积分公式计算 .研究结果表明 ,由 ... 详细信息

本文对球形演化的夸克 -胶子等离子体膨胀源进行了 2π干涉学分析 .夸克 -胶子等离子体的演化由相对论流体力学和熵密度的物态方程描述 ,而 2πHanbury Brown Twiss (HBT)关联函数由量子几率振幅的路径积分公式计算 .研究结果表明 ,由 2π干涉学得到的源的空间参量敏感地依赖于π介子发射源的相空间分布 ,源的膨胀速度导致HBT半径变小。

关键词：夸克-胶子等离子体干涉 π介子路径积分熵密度物态方程几率 HBT 发射参量

The application of nonlocal theory method in the coarse-grained molecular dynamics simulations of long-chain polylactic acid

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Acta mechanica Solida Sinica 2017年第6期30卷 630-637页

作者： Xiongjun Li Tan xiao Neng xiao Architecture and Civil Engineering Institute Guangdong University of Petrochemical Technology School of Engineering Sun Yat-sen University School of mechanical Engineering Purdue University

The micro-capsules used for drug delivery are fabricated using polylactic acid（PLA）,which is a biomedical material approved by the FDA.A coarse-grained model of long-chain PLA was built,and molecular dynamics（mD）simulations of the model were performed using a mARTINI force *** on the nonlocal theory,the formula for the initial elastic modulus of polymers considering the nonlocal effect was derived,and the scaling law of internal characteristic length of polymers was proposed,which was used to adjust the cut-off radius in the mD simulations of *** results show that the elastic modulus should be computed using nonlinear *** nonlocal effect has a certain influence on the simulation results of *** to the scaling law,the cut-off radius was determined and applied to the mD simulations,the results of which reflect the influence of the molecular weight change on the elastic moduli of PLA,and are in agreement with the experimental outcome.

关键词： Polylactic acid molecular dynamics simulation Nonlocal theory Scaling law Cut-off radius

Palatability and profitability of co-occurring seeds alter indirect interactions among rodent-dispersed trees

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Integrative Zoology 2022年第2期17卷 206-216页

作者： Zhishu xiao marcel HOLYOAK Charles j.KREBS xiaoqun HUANG State Key Laboratory of Integrated management of Pest Insects and Rodents in Agriculture Institute of ZoologyChinese Academy of SciencesChina University of Chinese Academy of Sciences BeijingChina Department of Environmental Science and Policy University of CaliforniaDavisUSA Department of Zoology University of British ColumbiaVancouverCanada

Beyond direct species interactions,seed dispersal is potentially affected by indirect seed–seed interactions among co-occurring nut-bearing trees which are mediated by scatter-hoarding animals as shared seed dispersers.A relevant question in such systems is to what extent different functional traits related to food palatability and profitability affect the kinds of indirect interactions that occur among co-occurring seeds,and the consequences for seed *** used field experiments to track seed dispersal with individually tagged seeds in both monospecific and mixed seed *** measured indirect effects based on 3 seed–seed species pairs from the family Fagaceae with contrasting seed size,tannin level,and dormancy in a subtropical forest in Southwest *** all else was equal,the presence of adjacently placed seeds with contrasting seed traits created different indirect effects measured through a variety of dispersal-related *** mutualism was reciprocal due to increasing seed dispersal in mixed seed patches with mixed differences in seed tannins and ***,differences in either seed size or dormancy in co-occurring adjacently placed seeds caused apparent competition with reduced seed removal or seed dispersal(distance)in at least one *** study supports the hypothesis that different functional traits related to food palatability and profitability in co-occurring seeds modify foraging decisions of scatter-hoarding animals,and subsequently cause indirect effects on seed dispersal among rodent-dispersed *** conclude that such indirect effects mediated by shared seed dispersers may act as an important determinant of seed dispersal for co-fruiting animal-dispersed trees in many natural forests.

关键词： dispersal distance functional trait scatter-hoarding rodents seed dispersal trait-mediated indirect interactions