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Population Spatial Distribution Based on luojia 1-01 Nighttime Light Image:A Case Study of Beijing

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Chinese Geographical Science 2021年第6期31卷 966-978页

作者： sun lu WANG Jia CHANG Shuping Institute of GIS RS&GPSBeijing Forestry UniversityBeijing100083China Beijing Key Laboratory of Precise Forestry Beijing Forestry UniversityBeijing100083China

With the continuous development of urbanization in China,the country’s growing population brings great challenges to urban *** mastering the refined population spatial distribution in administrative units,the quantity and agglomeration of population distribution can be estimated and *** will provide a basis for a more rational urban *** paper takes Beijing as the research area and uses a new luojia1-01 nighttime light image with high resolution,land use type data,Points of Interest(POI)data,and other data to construct the population spatial index system,establishing the index weight based on the principal component *** comprehensive weight value of population distribution in the study area was then used to calculate the street population distribution of Beijing in *** the population spatial distribution was visualize using GIS *** accuracy assessments by comparing the result with the WorldPop data,the accuracy has reached *** proposed method was validated as a qualified method to generate population spatial *** contrast of local areas,luojia 1-01 data is more suitable for population distribution estimation than the NPP/VIIRS(Net Primary Productivity/Visible infrared Imaging Radiometer)nighttime light *** geospatial big data and mathematical models can be combined to create more accurate population maps in the future.

关键词： luojia1-01 nighttime light image principal component analysis points of interest landuse type data population spatial distribution

Semiconductor quantum dot-doped glass as spectral converter for photovoltaic application

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Chinese Science Bulletin 2014年第1期59卷 16-22页

作者： lu sun Chun Jiang State Key Laboratory of Advanced Optical Communication System and Networks Shanghai Jiao Tong University

In this article,we focus on using the multiexciton generation(MEG)effect of quantum dot(QD)to realize quantum cutting of high-energy photons which will give rise to a remarkable increase of total photon *** avoid the complicated solving of Schro¨dinger equation,we take approximations and develop a method for fast evaluating the quantum efficiency of MEG *** this basis,we calculate the detailed balance limit of efficiency of Si single-junction solar cell with Si QD-doped glass placed on top of it as a spectral converter *** shows that the efficiency will reach 36%which is 6%higher than that without the converter *** have also explored the influence of QD radius,QD-doping density,QD,and host material,device working temperature on the efficiency.

关键词：半导体量子点掺杂玻璃转换器光谱应用光伏太阳能电池量子剪裁

Effect and Mechanism of Rare Earth Hydrotalcite Inhibiting Coal Spontaneous Combustion

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Journal of Wuhan University of Technology(Materials Science) 2024年第1期39卷 50-59页

作者：张小娟 LIU Bo 罗振敏 sun lu School of Safety Science and Engineering Xi’an University of Science and TechnologyXi’an 710054China

A hydrotalcite(layered double hydroxide, LDH) inhibitor which is suitable for the whole process of coal spontaneous combustion and a LDH inhibitor containing rare earth lanthanum elements were prepared. The inhibition effect and mechanism were analyzed by scanning electron microscopy(SEM),X-ray diffraction(XRD), thermal performance analysis, in-situ diffuse reflectance infrared spectroscopy and temperature-programmed experiment. The results have shown that the inhibitor containing lanthanum can play a good inhibitory role in every stage of coal oxidation. During the slow oxidation of coal samples, the inhibitor containing lanthanum ions can slow down the oxidation process of coal and increase the initial temperature of coal spontaneous combustion. At the same time, because the hydroxyl groups in LDHs are connected with-COO-groups on the coal surface through hydrogen bonds, the stability of coal is improved. With the increase of temperature, LDHs can remove interlayer water molecules and reduce the surface temperature of coal. CO release rate of coal samples decreases significantly after adding inhibitor containing lanthanum element, and the maximum inhibition rate of the inhibitor is 58.1%.

关键词： rare earth hydrotalcite coal spontaneous combustion mechanism

Cobalt-catalyzed Selective C--F Bond Activation and Alkylation of Polyfluoroaryl Imines

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Chinese Journal of Chemistry 2013年第7期31卷 927-932页

作者： Faguan lu Hongjian sun Xiaoyan Li School of Chemistry and Chemical Engineering Key Laboratory of Special Functional Aggregated Materials Ministry of Education Shandong University Jinan 250100 Shandong China

In this paper the C--F bond activation of polyfluoroaryl imines is explored at cobalt（0） center with an imine-N atom as an anchoring group. The reaction of F5C6-CH=N-（2＇-ClC6H4）（2） and FsC6-CH=N-C6H5 （3） with Co（PMe3h afforded the C-F bond activation products （ortho-F4C6-CH=N-（2＇-CIC6H4））Co（I）（PMe3）3 （5） and （ortho-F4C6-CH=N-C6Hs）Co（II）（F）（PMe3）2 （6）, while only n-（C=N） coordinated cobalt（0） complex （2,4,5- F3C6H2-CH=N-（4＇-ClC6H4））Co（0）（PMe3）3 （4） was obtained from 2,4,5-F3C6H2-CH=N-（4＇-C1C6H4）（1） without C--F bond activation. Complexes 4--6 were characterized through X-ray single crystal diffraction. It was also found that dialkylation of N-（perfluorobenzylidene）benzenamine with organozinc reagents could be catalyzed by Co（PMe3）4 via C,C-coupling reaction under mild conditions.

关键词： C--F bond activation cobalt imine organozinc reagent C,C-coupling

Prime in Quadratic Progressions on Average

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Acta Mathematica Sinica,English Series 2011年第6期27卷 1187-1194页

作者： Guang Shi lu Hai Wei sun Department of Mathematics Shandong University Ji'nan 250100 P. R. China

In this paper we study the distribution of primes in quadratic progressions on average. Our result improves a previous result of Baier and Zhao in some aspects.

关键词： Primes quadratic progressions circle method

Mechanical Simulation of a Diatom Frustule Structure

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Journal of Bionic Engineering 2015年第1期12卷 98-108页

作者： Jie lu Cheng sun Q. Jane Wang Department of Mechanical Engineering Northwestern University Evanston IL 60208

Diatoms possess intricately complicated nanopatterned silica outer shells, the so called frustules. Due to their excellent three-dimensional （3D） nanostructures, diatom frustules have attracted attentions from many fields to look for potential appli- cations, such as structural material design, light harvesting, photonics, molecular separation and bio-sensing. However, the mechanical property of frustule, especially the role of each single portion that structures a frustule, need to be clearly examined in order to provide a scientific support to frustule utilization. The reported work uses the Finite-Element （FE）-based simulation to investigate the relative mechanical properties of the frustule of the diatom Coscinodiscus sp. as compared with reference non-frustule structures. A three-dimensional model for the three featured layers of this frustule and a simplified model for its girdle band are built with the assistance of ABAQUS. A basic-cell concept is suggested; and the comparative results of several simulation groups are reported. The numerical results indicate that the seven-unit-cell model is able to catch the essential me- chanics of the Coscinodiscus sp. frustule under pressure and that the layered and porous structure of this frustule can effectively resist pressure.

关键词： diatom frustule FE simulation structure analysis bio-material

An overview of a unified theory of dynamics of vehicle–pavement interaction under moving and stochastic load

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Journal of Modern Transportation 2013年第3期21卷 135-162页

作者： lu sun Department of Civil Engineering The Catholic University of America International Institute of Safe Intelligent and Sustainable Transportation & Infrastructure Southeast University

This article lays out a unified theory for dynamics of vehicle-pavement interaction under moving and stochastic loads. It covers three major aspects of the subject： pavement surface, tire-pavement contact forces, and response of continuum media under moving and stochastic vehicular loads. Under the subject of pavement surface, the spectrum of thermal joints is analyzed using Fourier analysis of periodic function. One-dimensional and two-dimensional random field models of pavement surface are discussed given three different assumptions. Under the subject of tire-pavement contact forces, a vehicle is modeled as a linear system. At a constant speed of travel, random field of pavement surface serves as a stationary stochastic process exciting vehicle vibration, which, in turn, generates contact force at the interface of tire and pavement. The contact forces are analyzed in the time domain and the frequency domains using random vibration theory. It is shown that the contact force can be treated as a nonzero mean stationary process with a normal distribution. Power spectral density of the contact force of a vehicle with walking-beam suspension is simulated as an illustration. Under the subject of response of continuum media under moving and stochastic vehicular loads, both time-domain and frequency-domain analyses are presented for analytic treatment of moving load problem. It is shown that stochastic response of linear continuum media subject to a moving stationary load is a nonstationary process. Such a nonstationary stochastic process can be converted to a stationary stochastic process in a follow-up moving coordinate.

关键词： Vehicle-pavement interaction - Random field.Continuum medium - Spectral analysis ~ Green's function.Linear system

MicroRNA-30c inhibits pancreatic cancer cell proliferation by targeting twinfilin 1 and indicates a poor prognosis

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World Journal of Gastroenterology 2019年第42期25卷 6311-6321页

作者： lu-lu sun Ming Cheng Xiao-Dong Xu Department of Ultrasonography the First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450000Henan ProvinceChina Department of Information the First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450000Henan ProvinceChina Department of Breast Surgery the First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450000Henan ProvinceChina

BACKGROUND Studies have reported that microRNA-30c(miR-30c)has vital functions in the development and progression of multiple *** To investigate the clinical significance and role of miR-30c in pancreatic *** MiR-30c and twinfilin 1(TWF1)expression levels were analyzed in Gene Expression Omnibus datasets and validated in human pancreatic cancer by quantitative real-time polymerase chain reaction(RT-qPCR).The effects of miR-30c on pancreatic cancer cell growth,apoptosis,and cell cycle were evaluated by CCK-8 and flow cytometry ***,the in vivo effects were investigated using a subcutaneous xenograft *** gene prediction software and luciferase reporter assays were used to identify TWF1 as a direct target of *** The expression of miR-30c was significantly decreased in pancreatic cancer tissues and associated with ***-and loss-of-function assays showed that miR-30c suppressed pancreatic cancer cell proliferation in vitro and in ***-qPCR,Western blot,and luciferase reporter assays showed that miR-30c directly targeted *** expression level of miR-30c was negatively correlated with TWF1 expression in pancreatic cancer ***,the effects of ectopic miR-30c were rescued by TWF1 *** Our results identified the role of the miR-30c/TWF1 axis in pancreatic cancer progression and demonstrated that miR-30c might serve as a prognostic biomarker and therapeutic target for pancreatic cancer.

关键词： Pancreatic cancer MicroRNA-30c Proliferation Twinfilin 1

Modulation of photovoltaic behavior of dye-sensitized solar cells by electron donors of porphyrin dyes and cosensitization

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Chinese Chemical Letters 2015年第7期26卷 899-904页

作者： Bin Chen lu sun Yong-Shu Xie Shanghai Key Laboratory of Functional Materials Chemistry East China University of Science and Technology Department of Theoretical Chemistry and Biology School of Biotechnology KTH Royal Institute of Technology

Porphyrin dyes have received great attention due to their excellent photovoltaic performance in dye- sensitized solar cells （DSSCs）. In this work, dyes XCI-XC3 were synthesized by introducing various numbers of bis（4-methoxyphenyl）amino and p-hexyloxyphenyl groups to porphyrin meso-positions. The XC1 molecule contains two p-hexyloxyphenyl groups, and its DSSCs showed the power conversion efficiency of 4.81%. For XC2 and XC3, the replacement of p-hexyloxyphenyl with diphenylamino groups can effectively enhance the light harvesting around 500 nm. However, the highest occupied molecular orbitals （HOMOs） were elevated too much, which suppressed the dye regeneration processes, leading to low cell efficiencies of 2.51% and 1.27% for XC2, and XC3, respectively. To further improve the cell performance, an anthracene derivative Cl was used as the cosensitizer for XCl, which increased both the Jsc and Voc values, with an improved efficiency of 5.75：g.

关键词： Porphyrins DSSCs Cosensitizer Theoretical calculation