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Some issues on 2.5-D transient electromagnetic forward

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Journal of Central South University of Technology 2005年第Z1期12卷 177-182页

作者： XIONG Bin mao ya-dan School of Info-Physics and Geomatics Engineering Central South University Changsha 410083 China Institute of Geophysics and Geomatics China University of Geosciences Wuhan 430074 China

Numerical calculation for two integral transforms in 2.5-D transient electromagnetic forward is a difficult and key task, namely, the inverse Fourier transform and the inverse Laplace transform. Some effective algorithms for them were described. Based on the known algorithms in DC resistivity on wave-number distribution and selection, we proposed a principle on how to choose the least wave-number concerning the central-loop transient electromagnetic method. First, observe the behavior of transformation function curve with regard to wave-number in Fourier domain. In the light of its asymptote, ascertain the coverage scope of wave-number. Compared with analytic solution, the least wave-number in Fourier domain can be derived. Furthermore, the Laplace numerical inversion algorithm which needs only a few Laplace variables in pure real domain was also introduced here. The procedure was applied to forward modeling on transient electromagnetic field of a vertical magnetic dipole over uniform half-space to demonstrate them effectiveness and general applicability.

关键词： transient electromagnetic method 2.5-D forward modeling inverse fourier transform inverse laplace transform wave-number

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层状饱和多孔介质中Biot慢波的影响

石油地球物理勘探 2005年第4期40卷 428-432,443页

作者：毛娅丹中国地质大学地球物理与空间信息学院

本文基于Biot理论对P波在层状饱和多孔介质中的传播进行数值模拟。首先根据Kennett反射方法建立层状介质中地震波的数值模型,然后利用此模型研究层状饱和介质中Biot慢波对地震波性质的影响。文中分别在孔隙为弹性(考虑了P波扩散、Biot... 详细信息

本文基于Biot理论对P波在层状饱和多孔介质中的传播进行数值模拟。首先根据Kennett反射方法建立层状介质中地震波的数值模型,然后利用此模型研究层状饱和介质中Biot慢波对地震波性质的影响。文中分别在孔隙为弹性(考虑了P波扩散、Biot全局流及慢波影响)和黏弹性(可忽略慢波影响)两种情况下定量地分析了频率、孔隙率、层厚、渗透率以及岩石弹性模量对Biot慢波效应的影响。对比两种模型的数值模拟结果发现,在低频范围内,沉积盆地地层间液体压力的平衡作用(Biot慢波)能使P波产生显著的衰减;若这种衰减发生在浅层勘探地震波的频带内(几十到几百赫兹)。则介质层厚必然在几厘米到几十厘米范围内;介质越柔顺,孔隙率越大,渗透性越好,则慢波影响越大;在高频段,只要地层足够薄,介质的柔顺性足够好,界面处产生的慢波对高P波散射也会有很大影响。

关键词：层状介质 Biot慢波数值模拟 Kennett反射方法 Biot全局流 P波散射饱和多孔介质慢波 Biot理论数值模型

面向地学专业的“连续介质力学”课程教学研究

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中国地质教育 2015年第1期24卷 56-59页

作者：毛娅丹中国地质大学(武汉)地球物理与空间信息学院湖北武汉430074

"连续介质力学"课程面向地学专业的教学在我国起动较晚,尚在摸索阶段。作为一门专业基础课,它为后续"地球动力学"、"地震学"、"构造地质学"等一系列地学专业课打下力学基础,在专业培养方案中起着承上启下的作用。为使此课程更好地与后... 详细信息

"连续介质力学"课程面向地学专业的教学在我国起动较晚,尚在摸索阶段。作为一门专业基础课,它为后续"地球动力学"、"地震学"、"构造地质学"等一系列地学专业课打下力学基础,在专业培养方案中起着承上启下的作用。为使此课程更好地与后续地学专业课衔接,提高教学效率和教学质量,本文就课程中如何融入地学专业特色、优化教学内容、增加实践环节、采取多样化教学方式等方面进行了探讨。

关键词：连续介质力学地学专业特色教学方式

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近10年来乌鲁木齐市城市人口变动分析

西北师范大学学报（自然科学版） 2017年第2期53卷 118-122,134页

作者：毛亚会余丹林郑江华新疆大学资源与环境科学学院新疆乌鲁木齐830046 新疆大学智慧城市与环境建模普通高校重点实验室新疆乌鲁木齐830046 新泽西州蒙特克莱尔大学地球与环境研究系美国新泽西07043

基于2000年和2010年的全国人口普查数据,利用ArGIS和GS+Version 7软件对乌鲁木齐市街区人口数据空间化,分析其人口变动情况,并运用莫兰指数和半方差函数探索10年来各街区人口密度空间分布的相关性和变异性.结果表明,乌鲁木齐市人口增长... 详细信息

基于2000年和2010年的全国人口普查数据,利用ArGIS和GS+Version 7软件对乌鲁木齐市街区人口数据空间化,分析其人口变动情况,并运用莫兰指数和半方差函数探索10年来各街区人口密度空间分布的相关性和变异性.结果表明,乌鲁木齐市人口增长迅速,且各辖区表现出"人口数量增长率大密度小,增长率小而密度大"的差异性格局;各街区人口增长分布不均匀,街道之间人口数量差异越来越明显;2000—2010年乌鲁木齐市各街区人口密度空间分布相关性分析显示呈正相关性,且相关性增大;空间变异性分析显示人口密度空间分布整体结构越来越稳定,但影响空间分布的随机因素不确定性也在增加.

关键词：乌鲁木齐市人口分布相关性分析变异性分析

A new bisbenzylisoquinoline alkaloid from Plumulanelumbinis

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Chinese Chemical Letters 2016年第12期27卷 1755-1758页

作者： Xiao-Xiao Zhang Shuang-ChengMa Peng mao ya-dan Wang Beijing University of Chinese Medicine Beijing 100029 China National Institutes for Food and Drug Control Beijing 100050 China Shaanxi Momentum Pharmaceutical Co. LTD Xi'an 710075 China

One new bisbenzylisoquinoline alkaloid, neferine N-oxide （1）, along with three known compounds, neferine （2）, liensinine （3）, and isoliensinine （4）, were isolated from Plumulanelumbinis - the embryo of the seed of Nelumbonucifera. Their structures were elucidated by extensive spectroscopic analysis （MS, UV, IR, NMR）, and the absolute configurations were determined by experimental circulardichroism （CD） spectra. Compound 1 is a new naturally occurring bisbenzylisoquinoline alkaloid with an N-oxide functionality, and the CD spectrum of （1R, 1＇R） neferine is first reported. The antioxidant activities of compounds 1-4 were evaluated using the ORAC assay, which illustrated that all these compounds showed the different levels of oxygen radical absorbance capacity.

关键词： Plumulanelumbinis Bisbenzylisoquinoline alkaloid Neferine N-oxide ORAC assay Antioxidative activity

Correlating Photovoltaic Performance of Dye-Sensitized Solar Cell to the Film Thickness of Titania via Numerical Drift-Diffusion Simulations

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Chinese Journal of Chemical Physics 2016年第6期29卷 735-741,I0002页

作者： Yu-dan Wang Zhe Sun ya-jun Ren yan Zhang mao Liang Song Xue TianjinKeyLaboratoryofOrganicSolarCellsandPhotochemicalConversion SchoolofChemistryChemicalEnEineerinETianjinUniversityofTechnologyTianjin300384China SchoolofElectricEngineering TianjinUniversityofTechnologyTianjin300384China

The thickness of TiO2 film is vital to realize the optimization on photovoltaic performance of dye sensitized solar cells （DSSCs）. Herein, the process of charge separation in DSSCs was simulated by using a drift-diffusion model. This model allows multiple-trapping diffu- sion of photo-generated electrons, as well as the back reaction with the electron acceptors in electrolyte, to be mimicked in both steady and non-steady states. Numerical results on current-voltage characteristics allow power conversion efficiency to be maximized by varying the thickness of TiO2 film. Charge collection efficiency is shown to decrease with film thick- ness, whereas the flux of electron injection benefits from the film thickening. The output of photocurrent is actually impacted by the two factors. Furthermore, recombination rate constant is found to affect the optimized film thickness remarkably. Thicker TiO2 film is suitable to the DSSCs in which back reaction is suppressed sufficiently. On the contrary, the DSSCs with the redox couple showing fast electron interception require thinner film to alleviate the charge loss via recombination. At open circuit, electron density is found to decrease with film thickness, which engenders not only the reduction of photovoltage but also the increase of electron lifetime.

关键词： Dye-sensitized solar cells Titania Film thickness Simulation

The development of hollow multishelled structure: from the innovation of synthetic method to the discovery of new characteristics

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Science China Chemistry 2022年第1期65卷 7-19页

作者： Jiangyan Wang Zumin Wang dan mao dan Wang State Key Laboratory of Biochemical Engineering Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

Hollow multishelled structure(HoMS)is one of the most promising multifunctional *** high complexity of its structure makes the general and controllable synthesis of HoMS rather *** integration of multidisciplinary knowledge,a great achievement in HoMSs has been obtained in the past ***,the developed sequential templating approach has significantly boomed the progress of HoMS in composition and structure diversity and application *** implementation of the temporal-spatial ordering in HoMS makes it indispensable in solving the key scientific problems in energy conversion,catalysis and drug delivery *** development in HoMSs with novel intricate structures will bring new *** this review,we systematically introduce the development history of HoMSs,summarize the inspiration inherited from the previous research on hollow structures,and discuss the milestones in the development of HoMSs,with a focus on the sequential templating approach for HoMS fabrication,attractive temporal-spatial ordering property and dynamic smart behavior for advanced *** hope to reveal the inherent relationship between the precise synthesis of HoMS and its highly tunable compositional and structural characteristics,and point out its future direction to boost HoMS area further.

关键词： hollow multishelled structure sequential templating approach temporal-spatial ordering smart dynamic behavior

Theoretical investigation on water/metal fuel ramjet motor-thermodynamic cycle and thermodynamic calculation

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航空动力学报 2010年第5期25卷 1129-1138页

作者： yaNG ya-jing HE mao-gang School of Aerospace Xi'an Jiaotong UniversityXi'an 710049China State Key Laboratory of Multiphase Flow in Power Engineering School of Energy and Power EngineeringXi'an Jiaotong UniversityXi'an 710049China

For achieving high-speed requirement of underwater vehicle,a conceptual engine,which utilizes the hydroreactive characteristic of several metals under supercavitation environment,has been put forward. Especially,in order to obtain specific impulse as great as possible,a dual water injection system is taken into account. Then thermodynamic cycle model,which lead the improvement of power plant and energy system,is introduced in detail,and thermal efficiency is also analyzed. Furthermore,for investigating the performance of this kind of engine system,detailed thermodynamic calculation and analysis are achieved. Especially,regarding hydroreactive metal fuel Mg/AP/HTPB as our target fuel-rich propellant,considering its obvious deficient oxygen property and the energy property of magnesium/water reaction,theoretical calculation method is established by integrating chemical non-equilibrium with chemical equilibrium. Accordingly,low limit of primary water/fuel ratio is determined. In addition,the qualitative and quantitative relationship of performance parameters,such as theoretical specific impulse,nozzle exit temperature,characteristic velocity,etc.,versus water/fuel ratio is investigated respectively.

关键词： hydroreactive metal fuel water ramjet thermodynamic cycle thermal efficiency specific impulse

Developing new SSR markers from ESTs of pea(Pisum sativum L.)

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2010年第9期11卷 702-707页

作者： ya-ming GONG Sheng-chun XU Wei-hua mao Qi-zan HU Gu-wen ZHANG Ju DING ya-dan LI Institute of Vegetables Zhejiang Academy of Agricultural Science Hangzhou 310021 China Center of Analysis and Measurement Zhejiang University Hangzhou 310029 China

The development of expressed sequence tags(ESTs) from pea has provided a useful source for mining novel simple sequence repeat(SSR) *** the present research,in order to find EST-derived SSR markers,18 552 pea ESTs from the National Center for Biotechnology Information(NCBI) database were downloaded and assembled into 10 086 unigenes.A total of 586 microsatellites in 530 unigenes were identified,indicating that merely 5.25% of sequences contained *** most abundant SSRs within pea were tri-nucleotide repeat motifs,and among all the tri-nucleotide repeats,the motif GAA was the most abundant *** total,49 SSRs were used for primer ***-SSR loci were subsequently screened on 10 widely adapted varieties in *** these,nine loci showed polymorphic profiles that revealed two to three alleles per *** polymorphism information content value ranged from 0.18 to 0.58 with an average of ***,transferable analysis revealed that some of these loci showed transferability to faba *** of their polymorphism and transferability,these nine novel EST-SSRs will be valuable tools for marker-assisted breeding and comparative mapping of pea in the future.

关键词： Pea Expressed sequence tag(EST) Simple sequence repeat(SSR) Microsatellite