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An Assessment of Snow Cover Duration Variability Among Three basins of Songhua River in Northeast China Using Binary Decision Tree

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Chinese Geographical Science 2018年第6期28卷 946-956页

作者： YANG qian SONG Kaishan HAO Xiaohua CHEN Shengbo ZHU Bingxue Northeast Institute of Geography and Agroecology Chinese Academy of Sciences College of Geomatics and Prospecting Engineering Jilin Jianzhu University China Northwest Institute of Eco-environment and Resources Chinese Academy of Sciences College of Geo-exploration Science and Technology Jilin University

The dynamics of snow cover differs greatly from basin to basin in the Songhua River of Northeast China, which is attributable to the differences in the topographic shift as well as changes in the vegetation and climate since the hydrological year(HY) 2003. Daily and flexible multi-day combinations from the HY 2003 to 2014 were produced using Moderate Resolution Imaging Spectroradiometer(MODIS) from Terra and Aqua remote sensing satellites for the snow cover products in the three basins including the Nenjiang River basin(NJ), Downstream Songhua River basin(SD) and Upstream Songhua River basin(SU). Snow cover duration(SCD) was derived from flexible multiday combination each year. The results showed that SCD was significantly associated with elevation, and higher SCD values were found out in the mountainous areas. Further, the average SCDs of NJ, SU and SD basins were 69.43, 98.14 and 88.84 d with an annual growth of 1.36, 2.04 and 2.71 d, respectively. Binary decision tree was used to analyze the nonlinear relationships between SCD and six impact factors, which were successfully applied to simulate the spatial distribution of depth and water equivalent of snow. The impact factors included three topographic factors(elevation, aspect and slope), two climatic factors(precipitation and air temperature) and one vegetation index(Normalized Difference Vegetation Index, NDVI). By treating yearly SCD values as dependent variables and six climatic factors as independent variables, six binary decision trees were built through the combination classification and regression tree(CART) with and without the consideration of climate effect. The results from the model show that elevation, precipitation and air temperature are the three most influential factors, among which air temperature is the most important and ranks first in two of the three studied basins. It is suggested that SCD in the mountainous areas might be more sensitive to climate warming, since precipitation and air temp

关键词： Binary decision tree MODIS snow cover duration topography climate changes

Geochemistry and petrogenesis of Late Ladinian OIB-like basalts from Tabai,Yunnan Province,China

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Chinese Journal Of Geochemistry 2013年第4期32卷 337-346页

作者： ZHANG Jiawei HUANG Zhilong LUO Taiyi qian Zhikuan ZHANG Ying State Key Laboratory of Ore Deposit Geochemistry Institute of GeochemistryChinese Academy of Sciences University of the Chinese Academy of Sciences

Major and trace elements analysis has been carried out on the Late Ladinian Tabai basalts from Yunnan Province with the aim of studying their petrogenesis. Their SiO2 contents range from 43.63 wt.% to 48.23 wt.%. The basalts belong to the weakly alkaline(average total alkalis Na2 O+K2O=3.59 wt.%), high-Ti(3.21 wt.% to 4.32 wt.%) magma series. The basalts are characterized by OIB-like trace elements patterns, which are enriched in large ion lithosphile elements(LILE) including Rb and ba, and display negative K, Zr and Hf anomalies as shown on the spider diagrams. The Tabai basalts display light rare-earth elements(LREE) enrichment and are depleted in heavy rare-earth elements(HREE) on the REE pattern. Those dates indicate that the parental magma of the Tabai basalts was derived from low-degree(1%–5%) partial melting of garnet peridotite. The magma underwent olivine fractional crystallization and minor crustal contamination during their ascent. The Tabai basalts were related to a relaxation event which had triggered the Emeishan fossil plume head re-melting in the Middle Triassic.

关键词：玄武岩云南省地球化学成因重稀土元素塔中国 SiO2含量

Self-Adaptive Grinding for Blind Tip Reconstruction of AFM Diamond Probe

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Nanotechnology and Precision Engineering 2018年第2期1卷 150-155页

作者： Linyan Xu Qishan Guo Shuangbei qian Sen Wu State Key Laboratory of Precision Measuring Technology and Instruments(Tianjin University) Tianjin 300072China

Blind tip reconstruction(BTR) method is one of the favorable methods to estimate the atomic force microscopy(AFM) probe shape. The exact shape of the characterizer is not required for BTR, while the geometry of the sample may affect the reconstruction significantly. A cone-shaped array sample was chosen as a characterizer to be evaluated. The target AFM probe to be reconstructed was a diamond triangular pyramid probe with two feature angles, namely front angle(FA) and back angle(ba). Four conical structures with different semi-angles were dilated by the pyramid probe. Simulation of scanning process demonstrates that it is easy to judge from the images of the isolated rotary structure, cone-shaped, the suitability of the sample to be a tip characterizer for a pyramid probe. The cone-shaped array sample was repeatedly scanned 50 times by the diamond probe using an AFM. The series of scanning images shrank gradually and more information of the probe was exhibited in the images, indicating that the characterizer has been more suitable for BTR. The feature angle FA of the characterizer increasingly reduces during the scanning process. A self-adaptive grinding between the probe and the characterizer contributes to BTR of the diamond pyramid probe.

关键词： AFM diamond probe BTR Cone characterizer Self-adaptive Grinding

A new anti-hypoxia functional agent ——Schizophyllum commune fermented broth and its biochemical mechanisms

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Engineering Sciences 2013年第2期11卷 82-87页

作者： Hao Limin Lu Jike Wu Tianyi ba Jianming Guo Changjiang qian Ping Yu Jianyong Xing Xinhui The Quartermaster Equipment Institute of GLD of CPLA Department of Bioengineering Zhengzhou University High Altitude Medical Research Institute Department of Endocrinology Chinese PLA General Hospital Institute of Hygiene and Environmental Medicine Academy of Military Medical Sciences Department of Chemical Engineering and Technology Tsinghua University

In order to overcome hypoxia induced sickness, a stable source of anti-hypoxia functional agents, Sehizophyllum commune fermented broth has been developed in this study. Animal experiments were conducted to examine its anti-hypoxia activities and possible mechanisms involved. The acute hypoxic experiment showed that Sehizophyllum commune fermented broth could significantly prolong the survival time of mice. The underlying mechanisms were associated with improved energy metabolism based on a study carried out in rats exposed to a low pressure chamber simulating the low pressure environment of 8 000 m altitude. It was concluded that the Schizophyllum commune fermented broth was an effective anti-hypoxia functional agent and could be greatly bene- ficial to those living and working at high altitudes, such as people who reside in the reconstruction regions of Yushu.

关键词： altitude illness prevention and treatment anti-hypoxia aerobic metabolism glycogen adenosinetriphosphate (ATP)

Prenatal diagnosis of spinocerebellar ataxia type 3/Machado-Joseph disease in China's Mainland A case report

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Neural Regeneration Research 2011年第26期6卷 2047-2049页

作者： Lifang Lei Junling Wang Shen Zhang Hong Jiang Lu Shen qian Xu Xinxiang Yan Yi Yuan qian Pan Kun Xia Beisha Tang Department of Neurology Xiangya Hospital Central South University Changsha 410008 Hunan Province China Department of Neurology Xian-gya Third Hospital Central South University -Changsha 410013 Hunan Province China National Laboratory of Medical Genetics of China Changsha 410008 Hunan Province China

Spinocerebellar ataxia type 3/Machado-Joseph disease （SCA3/MJD） is a progressive, currently untreatable and ultimately fatal ataxic disorder that belongs to the group of neurological disorders known as CAG-repeat or polyglutamine diseases. Here, we present the first prenatal diagnosis of SCA3/MJD in China's Mainland in a woman who was known to carry an expanded CAG-trinucleotide repeat in the MJD1 gene. After evaluating motivation and psychological tolerance of the couple, amniocentesis was performed after 14 weeks of gestation. Polymerase chain reactions followed by T-vector cloning and direct sequencing were employed to evaluate the CAG-repeat number of the fetal MJD1 gene. We identified a truncated CAG expansion of 78 repeats in the MJD1 gene of the fetus compared with 81 repeats in his mother.

关键词： prenatal diagnosis spinocerebellar ataxia type 3/Machado-Joseph disease CAG-trinucleotide repeats genetic counseling

Influence of Absolute basicity and Capillary Porosity on Carbonation of Concrete

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Journal of Wuhan University of Technology(Materials Science) 2010年第5期25卷 889-892页

作者：巴明芳 School of Materials Science and Engineering Southeast University Jiangsu Key Lab of Construction Materials

The single influence of capillary porosity and coupling effects of absolute basicity and capillary porosity on concrete carbonation were investigated. The experimental results showed that carbonation rate of concrete at a given absolute basicity （AB） increased moderately with the increase of the porosity ranging from 6.2% to 9.25%, and increased rapidly with porosity from 9.25% to 12.8%.The coupling effect mainly embodied in disappeared mutation point of capillary porosity, and the distributing regions of carbonation depth were clearly partitioned in the coupling influence of absolute basicity and capillary porosity. A design method on carbonation related durability of concrete based on the coupling effects was proposed.

关键词： absolute basicity capillary porosity coupling effects carbonation rate

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六种蓝光烟火药的热力学研究

含能材料 2018年第5期26卷 432-435页

作者：霸书红蒋大千王树涛沈阳理工大学装备工程学院辽宁沈阳110159

为了比较不同蓝光烟火药的发光效果和探讨配方优化设计的新方法,利用REAL热力学计算程序对六种蓝光烟火药进行了热力学研究,建立了蓝光烟火药燃烧反应焓与火焰温度和辐射光子数之间的关系,根据计算得到的燃烧火焰温度和辐射蓝光的光子数... 详细信息

为了比较不同蓝光烟火药的发光效果和探讨配方优化设计的新方法,利用REAL热力学计算程序对六种蓝光烟火药进行了热力学研究,建立了蓝光烟火药燃烧反应焓与火焰温度和辐射光子数之间的关系,根据计算得到的燃烧火焰温度和辐射蓝光的光子数,优选了蓝光烟火药配方及配比。结果表明,六种不同蓝光烟火药的燃烧温度为1651～2880 K,这与利用NASA-CEA程序的计算结果一致,在最大波长处辐射的光子数为0.02011～0.0435 mol·kg^(-1),且产生蓝色火焰的主要辐射体为CuCl。借助蓝光烟火药的燃烧反应焓、火焰温度和辐射光子数之间的函数关系式,计算得出含KClO_3、2CuCO_3·Cu(OH)_2和S的蓝光烟火药燃烧温度为1651 K,辐射光子数为0.0435 mol·kg^(-1),在六种配方中其蓝光辐射效果最好,该配方的最佳配比为KClO_3/2CuCO_3·Cu(OH)_2/S=63/19/18,为其它火焰烟火剂的设计和优化提供了一种新的方法.

关键词：烟火药蓝光辐射体热力学参数

Differences and Similarities of Photocatalysis and Electrocatalysis in Two-Dimensional Nanomaterials:Strategies,Traps,Applications and Challenges

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Nano-Micro Letters 2021年第10期13卷 214-251页

作者： Weiqi qian Suwen Xu Xiaoming Zhang Chuanbo Li Weiyou Yang Chris RBowen Ya Yang Beijing Key Laboratory of Micro-Nano Energy and Sensor CAS Center for Excellence in NanoscienceBeijing Institute of Nanoenergy and NanosystemsChinese Academy of SciencesBeijing 101400People’s Republic of China Optoelectronics Research Center School of ScienceCollege of Life and Environmental SciencesMinzu University of ChinaBeijing 100081People’s Republic of China Institute of Materials Ningbo University of TechnologyNingbo 315016People’s Republic of China Department of Mechanical Engineering University of BathBath BA27AKUK School of Nanoscience and Technology University of Chinese Academy of SciencesBeijing 100049People’s Republic of China Center on Nanoenergy Research School of Physical Science and TechnologyGuangxi UniversityNanning 530004People’s Republic of China

Photocatalysis and electrocatalysis have been essential parts of electrochemical processes for over half a *** progress in the controllable synthesis of 2D nanomaterials has exhibited enhanced catalytic performance compared to bulk *** has led to significant interest in the exploitation of 2D nanomaterials for *** have been a variety of excellent reviews on 2D nanomaterials for catalysis,but related issues of differences and similarities between photocatalysis and electrocatalysis in 2D nanomaterials are still ***,we provide a comprehensive overview on the differences and similarities of photocatalysis and electrocatalysis in the latest 2D *** and traps for performance enhancement of 2D nanocatalysts are highlighted,which point out the differences and similarities of series issues for photocatalysis and *** addition,2D nanocatalysts and their catalytic applications are ***,opportunities,challenges and development directions for 2D nanocatalysts are *** intention of this review is to inspire and direct interest in this research realm for the creation of future 2D nanomaterials for photocatalysis and electrocatalysis.

关键词： 2D nanomaterials Photocatalysis Electrocatalysis Electrochemistry Photoelectrochemistry

Effects of Free Heave Motion on Wave Forces on Two Side-by-Side Boxes in Close Proximity Under Wave Actions

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China Ocean Engineering 2021年第4期35卷 490-503页

作者： HE Zhi-wei GAO Jun-liang ZANG Jun CHEN Hong-zhou LIU qian WANG Gang School of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212100China Centre for Infrastructure Geotechnical and Water Engineering(IGWE)Department of Architecture and Civil EngineeringUniversity of BathBA27AYUK School of Civil Engineering and Architecture Northeast Electric Power UniversityJilin 132012China College of Harbour Coastal and Offshore EngineeringHohai UniversityNanjing 210098China

Wave forces on two side-by-side boxes in close proximity under wave actions were analyzed using the OpenFOAM *** upstream box heaved freely under wave actions,whereas the downstream box remained *** comparison,a configuration in which both boxes were fixed was also *** effects of the heave motion of the upstream box on the wave loads,including the horizontal wave forces,vertical wave forces,and moments on the boxes,were the focus of this *** analyses showed that all frequencies at which the maximum horizontal wave forces,maximum vertical wave forces,and maximum moment appeared are dependent on the heave motion of the upstream box and that the effects of the heave motion on these frequencies are ***,these frequencies were observed to deviate from the corresponding fluid resonant ***,the heave motion of the upstream box reduced the wave forces acting on both boxes and altered the variation trends of the wave forces with the incident wave frequency.

关键词： fluid resonance wave forces narrow gap heave motion OpenFOAM