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Synthesis of 2,5-diformylfuran from renewable carbohydrates and its applications: A review

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Green Energy & Environment 2021年第1期6卷 22-32页

作者： Jinhang dai College of Environment and Resources Chongqing Technology and Business UniversityChongqing400067China

The synthesis of fine chemicals and fuel candidates from renewable biomass-based feedstocks has attracted much attention due to declining fossil *** value-added furan derivatives,such as 5-hydroxymethylfurfural(HMF),2,5-diformyfuran(DFF)and 2,5-furandicarboxylic acid,have been successfully produced from *** these,DFF,the aerobic oxidation product of HMF,is a key chemical and can be used in organic synthesis and functional polymer *** this review,different catalytic systems for the synthesis of DFF from monosaccharide,disaccharide and polysaccharide were summarized,while reaction pathways and catalyst stability were also ***,the applications of DFF were introduced in ***,prospects of more effective methods to DFF production and application were discussed.

关键词： 2,5-Diformyfuran Oxidation HMF Carbohydrate Biomass

PROSPECTING FOR COPPER (GOLD)-POLYMEtaL ORES FROM THE LANCANGJIANG TECTONIC ZONE IN WESTERN YUNNAN

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Geotectonica et Metallogenia 2001年第1期25卷 151-153页

作者： HU Bin, dai ta gen, XIE Li hua (Department of Geology, Central South University, Changsha 410083, China) Department of Geology Central South UniversityChangsha 410083China

The L ancangjiang tectonic zone in Western Yunnan is an important magmatic,meta- morphic and tectonic mobile zone of Southwestern China,whose geotectonic location is very unique. It is characterized by complex geological structures,perfectly developed strata,fre- quent magmatic activities,various degrees of metamorphism,rich ore resources and lots of metal deposits,thus formed a centralized zone of mineralization and also constituted one of the importantmetallogenicbelts of noble and nonferrousmetal *** the re- searching on geology for this zone is of great

关键词： Crustobody copper deposits metallogenetic perspectives Lancangjiang western Yunnan

湖南黄沙坪铅锌多金属矿床铅、硫同位素地球化学特征

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地球学报 2009年第1期30卷 89-94页

作者：息朝庄戴塔根刘悟辉中南大学地学与环境工程学院湖南长沙410083

黄沙坪铅锌多金属矿床是湘南的代表性矿床之一,矿床受SN向宝岭倒转背斜和观音打座倒转背斜的控制,赋存围岩以花岗斑岩与石英斑岩为主,矿石以铅锌硫化物矿石为主,对该矿床S同位素研究表明,δ34S值为～2.2‰～17.2‰。矿石Pb同位素组成206... 详细信息

黄沙坪铅锌多金属矿床是湘南的代表性矿床之一,矿床受SN向宝岭倒转背斜和观音打座倒转背斜的控制,赋存围岩以花岗斑岩与石英斑岩为主,矿石以铅锌硫化物矿石为主,对该矿床S同位素研究表明,δ34S值为～2.2‰～17.2‰。矿石Pb同位素组成206Pb/204Pb为17.893～18.772;207Pb/204Pb为15.580～16.045;208Pb/204Pb为38.490～41.560。研究表明,该矿床的硫源可能是岩浆来源与海水(地层)硫混合作用形成;矿床中异常铅矿化的铅是岩源来源。

关键词：铅硫同位素黄沙坪铅锌多金属矿床矿石

Beam dynamics design of an SP-FEL compact THz source

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Nuclear Science and Techniques 2010年第5期21卷 266-270页

作者： dai Dongdong dai Zhimin Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai 201800 China Graduate School Chinese Academy of Sciences Beijing 100049 China

In recent years,people are looking for a new compact THz source with high emission power,one potential choice is to build small accelerator with Smith-Purcell *** main difficulty is how to obtain high quality electron *** this paper,the beam dynamics design of a compact THz source is *** electron beam is produced by an electron gun and compressed by permanent *** electron gun is similar to the Shanghai EBIT,but permanent magnets are used,instead of the superconducting magnets in Shanghai *** this design,we can reduce the size and cost of the whole ***/Pandira was employed to simulate and optimize the magnetic *** was used to simulate the beam trajectories from the electron gun to the *** 2 centimeters around the center of longitudinal magnetic field,the calculation showed that the beam satisfies to our design aim.

关键词：动力学设计太赫兹紧凑型 FEL SP 束流永久磁铁 EBIT

槟榔干燥动力学模型及微观结构、代谢物变化规律研究

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热带作物学报 2025年第1期46卷 222-235页

作者：张晶代佳慧王世萍代文婷康效宁吉建邦胡玉娟海南省农业科学院三亚研究院海南三亚572000 海南省农业科学院农产品加工设计研究所海南海口570100 海口市槟榔加工研究重点实验室海南海口570100

干燥是槟榔加工的第1步,干燥过程直接影响槟榔的品质和货架期。为了明确槟榔热风干燥过程的水分变化、纤维微观结构及代谢物的变化规律,以期对槟榔干燥时间进行精准调控。本研究以槟榔鲜果和槟榔杀青果为研究对象,利用5种模型对不同温... 详细信息

干燥是槟榔加工的第1步,干燥过程直接影响槟榔的品质和货架期。为了明确槟榔热风干燥过程的水分变化、纤维微观结构及代谢物的变化规律,以期对槟榔干燥时间进行精准调控。本研究以槟榔鲜果和槟榔杀青果为研究对象,利用5种模型对不同温度下槟榔热风干燥曲线进行拟合,建立槟榔干燥动力学模型,同时利用扫描电子显微镜、LC-MS等探讨干燥过程中槟榔微观结构、代谢物的变化规律。结果表明:槟榔干燥曲线呈指数下降,干燥速率曲线分为加速和降速2个阶段,温度对干燥速率有显著影响;Page模型对槟榔热风干燥曲线拟合较好,模型决定系数(R^(2))在0.98以上,均方差(mean square deviation,RMSE)在0.02~0.06范围内,模型预测值和真实值差异不显著,可以较好地反映槟榔干燥过程中的水分变化规律。微观结构分析表明,随着干燥时间的增加槟榔纤维层变得致密、紧实,杀青处理导致槟榔纤维结构松散。质构结果表明,随着干燥时间的增加,槟榔硬度和咀嚼度增加,弹性降低。差异代谢物结果显示,干燥过程通过影响氨基酸代谢通路、中心碳代谢通路、亚油酸代谢通路、黄酮类生物合成、苯丙烷类生物合成进而影响有机酸、脂质和类脂分子等发生变化。研究结果为丰富槟榔加工基础研究,以及为槟榔热风干燥时间的选择提供理论依据。

关键词：槟榔干燥动力学模型微观结构代谢物质构

AN ITERATIVE HYBRIDIZED MIXED FINITE ELEMENT METHOD FOR ELLIPTIC INTERFACE PROBLEMS WITH STRONGLY DISCONTINUOUS COEFFICIENTS

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Journal of Computational Mathematics 2003年第3期21卷 257-276页

作者： dai-quYang JenniferZhao DepartmentofMathematics WayneStateUniversityDetroitMI48202USA DepartmentofMathematicsandStatistics UniversityofMichigan-DearbornDearbornMI48128USA

An iterative algorithm is proposed and analyzed based on a hybridized mixed finite element method for numerically solving two-phase generalized Stefan interface problems with strongly discontinuous solutions, conormal derivatives, and coefficients. This algorithm iteratively solves small problems for each single phase with good accuracy and exchange information at the interface to advance the iteration until convergence, following the idea of Schwarz Alternating Methods. Error estimates are derived to show that this algorithm always converges provided that relaxation parameters are suitably chosen. Numeric experiments with matching and non-matching grids at the interface from different phases are performed to show the accuracy of the method for capturing discontinuities in the solutions and coefficients. In contrast to standard numerical methods, the accuracy of our method does not seem to deteriorate as the coefficient discontinuity increases.

关键词： Mixed finite element method Interface problems Discontinuous solutions.

Load behaviors of a prefabricated wood framing house during lifting and transportation

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Forestry Studies in China 2007年第3期9卷 221-224页

作者： Hu Chuan-shuang Li Chong-gen Liao Hong-xia Li Kai-fu dai Na-xin College of Forestry South China Agricultural University Guangzhou 510642 P. R. China

Lifting for handling and flatbed truck transportation to the job site are important processes during manufacture of prefabricated wooden construction units like mini homes and building modules. Significant damage can occur to sections or components of units during these operations. Although damage usually will not impair its structural safety, it is costly to fix and causes the public to perceive prefabricated wooden buildings as low quality products. Field observations and preliminary numerical models for prefabricated units subject to lifting and transportation forces are summarized here. Once fully developed and verified, models will support the creation of damage mitigation strategies centered on structural details indicating how units are to be supported during lifting and transportation.

关键词： prefabricated house wooden timber construction load behavior mini home

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基于期货理论的矿业权竞买定价模型研究

财经理论与实践 2005年第4期26卷 106-109页

作者：喻建良戴塔根中南大学地学与环境工程学院

我国国有矿业权的交易基本上是通过拍卖的方式进行的,投资人在竞买过程中必须不断更新自己的报价。因此,需要一个利于调整各种参数的矿业权评价模型,或称竞买定价模型。竞买定价需要一个包含投资人期望收益率、无风险利率、投资方案、... 详细信息

我国国有矿业权的交易基本上是通过拍卖的方式进行的,投资人在竞买过程中必须不断更新自己的报价。因此,需要一个利于调整各种参数的矿业权评价模型,或称竞买定价模型。竞买定价需要一个包含投资人期望收益率、无风险利率、投资方案、资源量期望与回采率等直接影响矿业投资项目价值的因素在内的综合定价模型,以期货定价理论为基础推导出来的模型满足了投资者对竞买定价的这些要求,它与贴现现金流量法有相似之处,更适应于采矿投资项目的评价。

关键词：期货理论矿业权评价竞买定价投资

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国有矿业权转让利益相关者分类研究

财经理论与实践 2006年第3期27卷 101-105页

作者：喻建良戴塔根中南大学地学与环境工程学院湖南长沙410012

国有矿业权转让中存在众多的利益相关者,这些利益相关者明显来自不同的群体,按照米切尔和伍德提出的八类利益相关者分类方法分类后发现,这些利益相关者存在错位和定位不明确的现象、存在严重的利益冲突,必须通过合理设置权限、平衡利益... 详细信息

国有矿业权转让中存在众多的利益相关者,这些利益相关者明显来自不同的群体,按照米切尔和伍德提出的八类利益相关者分类方法分类后发现,这些利益相关者存在错位和定位不明确的现象、存在严重的利益冲突,必须通过合理设置权限、平衡利益关系等利益相关者管理办法加以解决。

关键词：国有矿业权利益相关者分类研究