Preparation and electrochemical performance of Ni-Sn alloys

[中文文摘]作为锂离子电池用非碳类负极材料,合金或金属间化合物备受关注。合金材料在循环过程中的体积变化是一个致命缺点。从抑制体积变化的角度出发,根据"BufferMatrix"的概念,将活性相植入到非活性相载体中。镍作为非活性相,锡作为活性相,用不同的方法制备了非晶态锡镍合金和晶态锡镍合金(Ni3Sn),研究了其形貌特征、晶体结构及电化学性能。在高温下用氢气还原的Ni3Sn具有稳定的晶体结构、较高的比容量(300mAh/g)和优良的循环性能。[英文文摘]As a carbon alternative anode material for Li-ion battery, alloys or inter-metal compounds were focused intensively.The alloy materials had a fatal disadvantage that the volume swelling existed during the cycles.The active materials embedded in inactive carrier based on the concept of "Buffer Matrix" to restrain the volume swellings. Ni as an inactive phase and Sn as an active phase, amorphous Ni-Sn alloy and crystalline Ni_3Sn were synthesized employing different methods which led to different morphology.The morphology characteristics , crystal structures and electrochemical performance of the materials were investigated.Ni3Sn reduced by H2 at high temperature had a stable crystal structure ,higher specific capacity (300 mAh/g) and excellent cycle performance.973项目(2002CB211804); 国家自然科学基金(20373058); 福建省科技项目(2003H044); 厦门市科技计划项目(3502Z2001234)

Analysis of Spatiotemporal Variability of Runoff Flashiness Index for Jiulongjiang River

通过分析河流flASHInESS指数的时空变异,进而评估水电开发、土地利用变化等人类活动对河流径流时空变异特征的影响。本研究选取地处东南沿海的中尺度流域——九龙江流域,基于1967~2007年近40年的水文资料,利用flASHInESS指数、基流指数等重要水文指数,并借助gIS、多元统计分析的方法来识别九龙江北溪与西溪两大干流流域近40年来径流时空变化特征及其影响因素。研究结果表明,九龙江流域近40年来径流特征发生显著的变化,流域面积是影响九龙西溪和北溪径流时空变化的自然因素,大坝建设、水电开发改变了九龙江流域的水文条件,进而影响了径流量的年内分布规律及泥沙输出特征,土地利用变化是影响流域径流特征变化的潜在因子。研究结果可为流域水资源管理提供科学依据。Spatiotemporal variability of the runoff flashiness index was explored and thereby used to evaluate the effect of human activities including dam construction and land use change on runoff variation.The Jiulongjiang River Basin, the medium-sized coastal watershed located in SE China, was chosen to analyze the characteristics of the runoff variation with Flashiness Index(FI)and Baseflow Index(BFI) for the north reach and west river of the Jiulongjiang River, based on the forty-year hydrologic data from1967 to 2007.The geographical information system and multivariate analysis were coupled to characterize the spatiotemporal varia-tion of the runoff and identify its influencing factor.The results show that the hydrological condition in the Jiu longjiang River Basin was altered significantly in the past 40 year, represented by a decreasing tend for FI and an increasing trend for BFI.Furthermore, the watershed area is the major natural factor leading to spatiotemporal variability of the runoff flashiness index for the north reach and west reach of the Jiulongjiang River.The Dam construction and hydropower development made the hydrological condition changed in the Jiulongjiang River Basin, which greatly influenced the seasonal variability of the runoff and sediment dis-charge.The land use change was identified as a potential factor influencing the runoff variation of the Jiulong River Basin.国家自然科学基金项目(40901100;40810069004); 福建省水利厅项目(FJSW2013038

The Synthesis, Characteristics and Performance of CNT Composites as Anodic Materials in Litium-ion Battery

[中文文摘]作为锂离子电池负极材料,碳纳米管和金属锡或其氧化物都曾引起过人们浓厚的兴趣,但由于其自身的缺陷,这些材料均未能得到进一步的发展.本文以不同方法合成了碳纳米管和金属锡或其氧化物的复合材料,对其结构、形貌进行表征,并考察它的电化学性能.[英文文摘]As an anodic material for lithium ion battery the carbon nano-tube (CNT) and some compounds based on tin have ever been investigated intensively. The fruited progress has not been made yet, however. In this paper the composites of CNT and Sn/SnO_(2)were synthesized employing two methods and characterized by SEM and XRD. And the electrochemical performance of the composites was investigated.973项目(2002CB211800); 国家自然科学基金(20373058); 福建省科技项目(2003H044)资助

市政污泥热解制备生物炭实验研究

引言生物炭是有机物质在缺氧或贫氧气氛下经热裂解过程产生的固体产物,目前对生物炭的研究兴趣源于对亚马逊盆地黑土（Terra Preta）的认识,亚马逊盆地黑土含有丰富的生物炭,多年耕种后,仍保持持久肥力。研究表明,生物炭是稳定的碳载体,在土壤中可保持长达百年至千年之久,土壤中施用生物炭可提高土壤中有机碳以及腐殖质含量,从而提高土壤的养分吸持容量及持水容量

The Synthesis, Characteristics and Performance of CNT Composites as Anodic Materials in Litium-ion Battery

作为锂离子电池负极材料,碳纳米管和金属锡或其氧化物都曾引起过人们浓厚的兴趣,但由于其自身的缺陷,这些材料均未能得到进一步的发展.本文以不同方法合成了碳纳米管和金属锡或其氧化物的复合材料,对其结构、形貌进行表征,并考察它的电化学性能.As an anodic material for lithium ion battery the carbon nano-tube (CNT) and some compounds based on tin have ever been investigated intensively. The fruited progress has not been made yet, however. In this paper the composites of CNT and Sn/SnO_(2)were synthesized employing two methods and characterized by SEM and XRD. And the electrochemical performance of the composites was investigated.作者联系地址：厦门大学化学系,厦门大学化学系,厦门大学化学系,厦门大学化学系,厦门大学化学系,厦门大学化学系 厦大宝龙电池研究所,固体表面物理化学国家重点实验室,福建厦门361005 ,厦大宝龙电池研究所,固体表面物理化学国家重点实验室,福建厦门361005 ,厦大宝龙电池研究所,固体表面物理化学国家重点实验室,福建厦门361005 ,厦大宝龙电池研究所,固体表面物理化学国家重点实验室,福建厦门361005 ,厦大宝龙电池研究所,固体表面物理化学国家重点实验室,福建厦门361005 ,厦大宝龙电池研究所,固体表面物理化学国家重点实验室,福建厦门361005Author's Address: State Key Lab for Physical Chemistry of Solid Surface, Xiamen Univ., PowerLong Battery Institute, Department of Chemistry , Xiamen University, Xiamen 361005, Chin

基于FPGA的数字电源调节器研究与设计

详细描述了基于FPGA方案的数字电源调节器。首先介绍了数字调节器的硬件功能模块设计,重点对用于采样电源输出电流的高速高精度AD7634的工作原理做了描述,并给出了AD7634采集一个电压信号的工作波形;其次介绍了数字调节器的软件设计,包括调节器算法、功能以及在FPGA内的实现方法;最后,以一台15 A/15 V校正磁铁电源为样机,进行了闭环调节实验,给出了测试结果

离子加速器高精度脉冲/直流数字电源

本发明涉及一种离子加速器高精度脉冲/直流斩波数字电源。它包括：离子加速器高精度通用数字电源调节器，离子加速器通用数字电源控制器，低压变压器，三相二极管整流与滤波电路，H桥双向斩波电路，高精度电流反馈电路以及负载电路。通过使用离子加速器高精度通用数字电源调节器对斩波式非隔离开关电路的进行控制和调节，实现了一种能脉冲和直流两种运行方式工作的离子加速器高精度数字电源，满足离子加速器数字电源高精度数据采集、高速高精度数字调节、高精度PWM输出等要求；本发明工作方式简单可靠，可以通过本地人机界面对数字电源通讯和操作也可利用CAN总线组网方式对单台或多台数字电源采用远程网络控制；可应用于普通离子加速器和专用离子治癌加速器，或其它类似用途

数字脉冲电源同步定时触发系统

<span style="color: rgb(69, 69, 69); font-family: Arial, Helvetica, sans-serif; line-height: 21px; text-indent: 24px;">&nbsp; &nbsp; &nbsp; &nbsp; 本实用新型涉及用于实现多台数字脉冲电源远程同步定时触发控制的一种数字脉冲电源同步定时触发系统。其特点在于包括与控制计算机互联的以现场可编程门阵列FPGA为硬件的触发源服务器，触发源服务器与一级扇出器相连，一级扇出器分别与多路无时间差的二级扇出器对应相连，二级扇出器与数字脉冲电源模块相连。该系统能实现离子加速器数字脉冲电源或相关工业领域多台数字脉冲电源按照设定的时间序列同步启动或者分组定时同步启动控制，满足了相关领域数字脉冲电源在远程控制方式下灵活定时同步启动的要求。</span