检索结果-南通市图书馆

Late Cenozoic Chemical Weathering and Environmental Changes Recorded in the Co Ngoin Sediments,Central Qinghai-Tibet Plateau

引用

Acta Geologica Sinica(English Edition) 2005年第3期79卷 384-391页

作者： CHENShiyue JINZhangdong WANGSumin SHENJi NanjingInstituteofGeographyandLimnology ChineseAcademyofSciencesNanjingJiangsu210008／／SchoolofEnvironmentandPlanningLiaochengUniversityLiaochengShandong252059 NanjingInstituteofGeographyandLimnology ChineseAcademyofSciencesNanjingJiangsu210008／／InstituteofEarthEnvironmentChineseAcademyofSciencesXi＇anShaanxi710075 NanjingInstituteofGeographyandLimnology ChineseAcademyofSciencesNanjingJiangsu210008

A series of faulted inland basins were developed in the central Qinghai-Tibet Plateau, among which the Co Ngoin Basin containing thick lacustrine sediments is located in the peripheral area of the Indian monsoon. In this paper, we present the weathering history and paleoclimatic changes in the last 2.8 Ma based on studies of high-resolution temporal distributions of Sr, Rb and Zr concentrations, Rb/Sr and Zr/Rb ratios and δ 13C and TOC for the Co Ngoin sediments, in combination with the sediment properties, grain size distribution and clay mineralogy. The sedimentary records indicate three environmental stages in the last 2.8 Ma. At the core depth of 197?170 m (about 2.8?2.5 Ma), low-intensity chemical weathering in the Co Ngoin catchment was experienced under warm-dry to cool-wet climate conditions with relatively low Sr concentration and high Rb/Sr and Zr/Rb ratios. The sudden occurrence of both subalpine coniferous forest and coarse sand and gravel sediments in the Co Ngoin core reflects a strong tectonic uplift. The high Sr concentrations and low Rb/Sr and Zr/Rb ratios reflect a relatively strong chemical weathering between 2.5 Ma and 0.8 Ma (at the core depth of 170?38.5 m) under a temperate/cool and wet climate, characterized by mud and silt with fine sand, probably indicating a stable process of denudation and planation of the plateau. Above the depth of 38.5 m (about 0.8?0 Ma), the coarsening of sediments indicates a strong tectonic uplift and a relatively low intensity of chemical weathering as supported by the record of sediments having relatively low Sr concentrations and high Rb/Sr and Zr/Rb ratios. Since then, the plateau has taken the shape of the modern topographic pattern above 4000 m a.s.l.

关键词： Qinghai-Tibet Plateau Co Ngoin Rb/Sr Zr/Rb δ 13C TOC environmental evolution

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Two-dimensional MoS_(2)/diamond based heterojunctions for excellent optoelectronic devices:current situation and new perspectives

引用

Rare Metals 2023年第10期42卷 3201-3211页

作者： Liang-Rui Zou Xiao-Dan Lyu Dan-Dan Sang Yu Yao Shun-Hao Ge Xue-Ting Wang Chuan-Dong Zhou Hai-Long Fu Hong-Zhu Xi Jian-Chao Fan Cong Wang Qing-Lin Wang Shandong Key Laboratory of Optical Communication Science and Technology School of Physics Science and Information TechnologyLiaocheng UniversityLiaocheng252000China College of Mathematics and Physics Beijing University of Chemical TechnologyBeijing100029China Division of Physics and Applied Physics School of Physical and Mathematical SciencesNanyang Technological UniversitySingapore637371Singapore Shandong liaocheng Laixin Powder Materials Science and Technology Co. Ltd.Liaocheng252000China Zhejiang Province Key Laboratory of Quantum Technology and Device Department of PhysicsZhejiang UniversityHangzhou310027China The Institute of Anhui Huadong Photoelectric Technology Wuhu241002China

Two-dimensional(2D)semiconductor molybdenum disulfide(MoS_(2))can be used as n-channel and is considered as a key candidate material to advance the promising development of optoelectronic *** high thermal conductivity,breakdown voltage,carrier mobility,and high saturation velocity of diamond offer the possibility of making it high-frequency device material in hightemperature and high-power *** addition of 2D MoS_(2)nanolayers and nanosheets to diamond thin film to form heterojunction can improve the carrier transport performance of the optoelectronic device in harsh *** this perspective,the prospects of 2D MoS_(2)/diamond heterojunction for challenges and new designs of optoelectronic applications are discussed,including photodetectors,memories,transistors,light emission diodes,and electron field emission devices to further explore the development of 2D material device field in complex environments.

关键词： MoS_(2) Optoelectronics Heterojunction Diamond Extreme environment

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Modified Josephson Equation for Mesoscopic Parallel LC Circuit Including a Josephson Junction

引用

Chinese Physics Letters 2009年第1期26卷 284-287页

作者：苏杰王继锁梁宝龙张晓燕 School of the Physics Science and Information Technology Liaocheng University Shangdong 252059

By introducing the entangled state representation, parallel LC circuit including a 3osephson junction equation associated with the modification of the motion equation. the Cooper-pair number-phase quantization of the mesoscopic is realized. In the Heisenberg picture, the modified Josephson Faraday equation about the inductance is deduced from the

关键词： NUMBER-PHASE QUANTIZATION ALGORITHM STATE MODEL

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Kraus operator solutions to a fermionic master equation describing a thermal bath and their matrix representation

引用

Chinese Physics B 2016年第4期25卷 42-46页

作者：孟祥国王继锁范洪义夏承魏 School of Physical Science and Information Engineering Liaocheng University Shandong Provincial Key Laboratory of Optical Communication Science and Technology Liaocheng University Shandong Provincial Key Laboratory of Laser Polarization and Information Technology Department of Physics Qufu Normal University Department of Material Science and Engineering University of Science and Technology of China

We solve the fermionic master equation for a thermal bath to obtain its explicit Kraus operator solutions via the fermionic state approach. The normalization condition of the Kraus operators is proved. The matrix representation for these solutions is obtained, which is incongruous with the result in the book completed by Nielsen and Chuang [Quan- tum Computation and Quantum Information, Cambridge university Press, 2000]. As especial cases, we also present the Kraus operator solutions to master equations for describing the amplitude-decay model and the diffusion process at finite temperature.

关键词： Kraus operator solution matrix representation thermal bath fermionic entangled state represen-tation

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Effects of initial frequency chirp on the linear propagation characteristics of the exponential optical pulse

引用

Chinese Physics B 2006年第8期15卷 1831-1837页

作者：郑宏军刘山亮 Department of Electronic Science and Technology Huazhong University of Science and Technology Wuhan 430074 China Institute of Optical Communication Liaocheng University Liaocheng 252059 China

In this paper, the linear propagation characteristics of the exponential optical pulse with initial linear and nonlinear frequency chirp are numerically studied in a single mode fibre for β2 〈 0. It can be found that the temporal full width at half maximum and time-bandwidth product of exponential pulse monotonically increase with the increase of propagation distance and decrease with the increase of linear chirp C for C 〈 0.5, go through an initial decreasing stage near ζ= 1, then increase with the increase of propagation distance and linear chirp C for C 〉 0.5. The broadening of pulses with negative chirp is faster than that with positive chirp. The exponential pulse with linear chirp gradually evolves into a near-Gaussian pulse. The effect of nonlinear chirp on waveform of the pulse is much greater than that of linear chirp. The temporal waveform breaking of exponential pulse with nonlinear chirp is first observed in linear propagation. Furthermore, the expressions of the spectral width and time-bandwidth product of the exponential optical pulse with the frequency chirp are given by use of the numerical analysis method.

关键词： fibre optics frequency chirp numerical analysis exponential optical pulse

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

基于一种新型超腔的高亮度激光同步辐射分析(英文)

引用

强激光与粒子束 2011年第9期23卷 2537-2541页

作者：孟现柱聊城大学物理科学与信息工程学院山东聊城252059

提出了一种由一对抛物面构成的超腔的技术方案,计算了超腔汇聚点处的总光子密度。利用康普顿散射理论对基于抛物面超腔的激光同步辐射及其光子产额进行了讨论和计算。结果表明:当超腔镜面的反射率等于99.99%时,在超腔碰撞点处的总光子... 详细信息

提出了一种由一对抛物面构成的超腔的技术方案,计算了超腔汇聚点处的总光子密度。利用康普顿散射理论对基于抛物面超腔的激光同步辐射及其光子产额进行了讨论和计算。结果表明:当超腔镜面的反射率等于99.99%时,在超腔碰撞点处的总光子数密度大约是初始激光束在碰撞点处光子数密度的5 000倍,对应康普顿垂直散射的光子产额大约是电子束与初始激光束在碰撞点处发生康普顿垂直散射时的5 000倍。

关键词：抛物面超腔康普顿散射光子产额

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

The study of the shape anisotropy in patterned permalloy films

引用

Chinese Physics B 2007年第6期16卷 1725-1727页

作者：张栋翟亚翟宏如 School of Physics Science and Information Engineering Liaocheng University Liaocheng 252059 China Department of Physics Southeast University Nanjing 210096 China National Laboratory of Solid Microstructure Center for Materials Analysis Nanjing University Nanjing 210093 China

In this paper a systematic ferromagnetic resonance study shows that an in-plane magnetic anisotropy in the patterned micron octagon permalloy （Ni80Fe20） elements is mainly determined by the element geometry. The easy-axis is along the edge of the elements, and the hard-axis is along the diagonal. The shape anisotropy of the octagon elements is determined by square and equilateral octagon, and the theoretical calculation was studied on the shape anisotropy. The shape anisotropy of rectangular was calculated by using the same theory.

关键词： patterned film shape anisotropy ferromagnetic resonance

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

机械研磨对电沉积Ni镀层微观结构与性能的影响(英文)

引用

Transactions of Nonferrous Metals Society of China 2012年第8期22卷 1989-1994页

作者：班朝磊邵鑫马杰陈辉聊城大学材料科学与工程学院聊城252059 聊城有色金属研究院聊城252059

在电沉积Ni过程中,向镀液中加入介质小球,介质小球以不同频率冲击镀件表面对镀层形成机械研磨。用SEM观察镀层表面、截面形貌,用TEM、XRD研究镀层的微观结构与结晶状态,测试镀层的极化曲线(PC)与交流阻抗频谱(EIS)等电化学性能。测试镀... 详细信息

在电沉积Ni过程中,向镀液中加入介质小球,介质小球以不同频率冲击镀件表面对镀层形成机械研磨。用SEM观察镀层表面、截面形貌,用TEM、XRD研究镀层的微观结构与结晶状态,测试镀层的极化曲线(PC)与交流阻抗频谱(EIS)等电化学性能。测试镀层的显微硬度与抗拉强度等力学性能。结果表明:在电沉积Ni过程中,对镀层实施机械研磨使镀层表面变得光滑,镀层孔隙率降低,致密度增加,镀层厚度减小,机械研磨促进镀层表面与内部晶粒尺寸的明显细化及镀层内部的压应力形成,从而导致镀层的耐蚀能力显著增强,抗拉强度与硬度显著提高。

关键词：电镀机械研磨镍镀层耐蚀性

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Effect of initial linear chirp on collision characteristics of two solitons in the birefringent fibre

引用

Chinese Physics B 2007年第7期16卷 2023-2027页

作者：郑宏军刘山亮徐静平 Department of Electronic Science and Technology Huazhong University of Science and Technology Wuhan 430074 China Institute of Optical Communication Liaocheng University Liaocheng 252059 China

The collision characteristics of the orthogonally polarized solitons with initial linear frequency chirp in the linear birefringent fibre for β2 〈 0 are numerically studied. It is found that initial chirp changes the threshold value of solitons to form the bound-state in the birefringent fibre. The effect of initial positive chirp on the threshold value is more obvious than that of negative chirp. In the case of （δ= 0.7 and initial interval 2τ0 = 1.25, the two solitons are mutually bound for 0.2 ≤ C ≤ 1, and they do not form the bound-state for -1 ≤ C 〈 0.2. Frequency shifts increase with the increase of chirp parameter C for -1 ≤ C 〈 0.2, and have the oscillatory structure for C ≥ 0.2. The effect of positive chirp on temporal FWHM is greater than that of negative chirp. The peak of temporal waveform oscillates with the propagation distance. The period and amplitude of the oscillation for the chirped case are greater than those for the unchirped case, and they vary with the increase of ｜C｜. The peak of output temporal waveform can be controlled by changing the initial chirp.

关键词： frequency chirp solitons collision linear birefringent fibre soliton-bound state

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

新型磷钨酸基固体酸催化油酸酯化合成生物柴油（英文）

引用

燃料化学学报 2017年第3期45卷 303-310页

作者：王红红刘丽君龚树文聊城大学化学化工学院山东聊城252059

利用磷钨酸(PTA)与1,2,3-三氮唑-4,5-二羧酸(TDA)在水溶液中的反应,合成了一种新的固体酸TDA-PTA,采用X射线粉末衍射(XRD)、扫描电镜(SEM)、红外光谱(FT-IR)、热重(TG)以及电位滴定等方法对其进行了表征,并以油酸与甲醇的酯化反应为探... 详细信息

利用磷钨酸(PTA)与1,2,3-三氮唑-4,5-二羧酸(TDA)在水溶液中的反应,合成了一种新的固体酸TDA-PTA,采用X射线粉末衍射(XRD)、扫描电镜(SEM)、红外光谱(FT-IR)、热重(TG)以及电位滴定等方法对其进行了表征,并以油酸与甲醇的酯化反应为探针反应,考察了其催化性能,探讨了催化剂用量、醇酸物质的量比、反应时间、反应温度以及催化剂重复利用次数等对产物收率的影响。结果表明,TDA-PTA不仅保留有磷钨酸典型的Keggin结构,而且具有较强的酸强度;经修饰后,催化剂具有规整的球形形貌,比表面积明显大于磷钨酸;TDA-PTA在油酸与甲醇的酯化反应中表现出了优良的催化活性,尤其显示出好的重复利用性,六次使用后,仍得到86.8%的油酸甲酯产率,催化剂的物相以及Keggin结构没有明显变化。

关键词：杂多酸固体酸催化酯化油酸

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：