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Urban Energy Efficiency from Cities in China and Policy Implications

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Chinese Journal of Population,Resources and Environment 2010年第4期8卷 19-25页

作者： li Zhi li Pei li guoping School of Economics and Finance Xi＇an Jiaotong UniversityXi＇an Shaanxi 710061China Department of Real Estate National University of Singapore117566SingaporeSingapore

Using 1995-2006 panel data for 210 cities,this article firstly measures total factor energy efficiency for Chinese cities with constant return to scale data envelopment analysis model,and then describes the features of regional *** results show that the changing trend displays four "reversed U" shapes.A turning point of widening gap occurred among cities in 2000 and there was a certain convergence among four *** energy efficiency level is *** with low efficiency and high energy input will be the focus of energy-saving and reducing *** to Tobit model,resource endowment,temperature,industrial structure,technology level and variety of policy factors should be treated differently in different situations.

关键词： total-factor energy efficiency difference impact factor cities

Establishment of an Objective Standard for the Definition of Binary Tropical Cyclones in the Western North Pacific

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Advances in Atmospheric Sciences 2020年第11期37卷 1211-1221页

作者： Fumin REN Yanjun XIE Biwen YIN Mingyang WANG guoping li State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China School of Atmospheric Sciences Chengdu University of Information TechnologyChengdu 610225China Zhuzhou Meteorological Observatory Zhuzhou 412000China Qinhuangdao Meteorological Observatory Qinhuangdao 066000China

To develop an objective standard for defining binary tropical cyclones(BTCs)in the western North Pacific(WNP),two best-track datasets,from the China Meteorological Administration and the Joint Typhoon Warning Center,were adopted for statistical analyses on two important characteristics of BTCs-two TCs approaching each other,and counterclockwise *** on the high consistency between the two datasets,we established an objective standard,which includes a main standard for defining BTCs and a secondary standard for identifying typical/atypical *** main standard includes two requirements:two coexisting TCs are a pair of BTCs if(i)the separation distance is≤1800 km,and(ii)this separation maintains for at least 12 ***,the secondary standard defines a typical BTC as one for which there is at least one observation when the two TCs approach each other and spin counterclockwise *** the standard,the ratio of typical BTCs increases as the BTC duration increases or the minimum distance between the two TCs ***,using the JTWC dataset,it was found that there are 505 pairs of BTCs during the period 1951−2014,including 328 typical BTCs and 177 atypical BTCs,accounting for 65.0%and 35.0%of the total,*** addition,a study of two extreme phenomena-the maximum approaching speed and the maximum counterclockwise angular velocity in typical BTCs-shows that the configuration of the circulation conditions and the distribution of the BTCs favor the formation of these extreme phenomena.

关键词： objective standard binary tropical cyclones Western North Pacific

Effect of Heat Treatment on the Wear Properties of Selective Laser Melted Ti–6Al–4V Alloy Under Different Loads

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Acta Metallurgica Sinica(English Letters) 2022年第3期35卷 517-525页

作者： Lu Yao Yeqin He Ziqiang Wang Binyi Peng guoping li Yang liu Faculty of Mechanical Engineering&Mechanics Ningbo UniversityNingbo 315211China Key Laboratory of Impact and Safety Engineering Ministry of EducationNingbo 315211.China

As is well known,titanium alloy precipitates when subjected to aging treatment,which poses great influence on its mechanical ***,solution and solution-aging treatments were conducted in this work,and the wear performance was investigated under diff erent normal *** results showed that acicularα′martensite in the original selective laser melted Ti–6 Al–4 V was decomposed intoα+βphases after the solution treatment,and then Ti;Al nanoparticles clusters were further formed in theα-matrix after the solution-aging *** coefficient of friction decreased straightly as the normal load was increased from 20 to 100 N,and the wear mechanisms were characterized by abrasion,adhesive and oxidative *** wear rate of solution and solution-aging treated samples increased significantly comparing to the as-built counterpart,but the increment of the solution-aging treated sample was smaller than that of the solution-only treated sample,because of the Ti;Al precipitation in the solution-aging treated *** particles provided ball-like effect,reduced material losses and stabilized the wear *** these factors contributed to the improvement in wear properties of the parts made by selective laser melting.

关键词： Selective laser melting Ti–6Al–4V Wear performance Heat treatment

Down-scaling LUCC based on the histo-variogram

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Science China(Technological Sciences) 2009年第5期52卷 1348-1353页

作者： ZHANG Hao CAO ChunXiang li guoping YANG Hua li XiaoWen QIN Jun State Key Laboratory of Remote Sensing Science Institute of Remote Sensing ApplicationChinese Academy of SciencesBeijing 100101China School of Earth and Space Sciences Peking UniversityBeijing 100871China State Key Laboratory of Remote Sensing Science Beijing Normal UniversityBeijing 100875China Institute of Tibetan Plateau Research Chinese Academy of SciencesBeijing 100083China

In remote sensing applications,accurate extraction of land type area after classification is very *** for images of land use/cover change(LUCC) obtained from the special spatial resolution re-mote sensing data,it will be of great significance to obtain the land type area information with higher resolution by making use of spatial distribution characteristcs information of the land type itself first and further scaling-down in a given scale threshold on the basis of the existing spatial resolution *** explicit expression of the relationship between the measurement scale,global fractal dimension and the land type area corresponding to different measurement scales is obtained on the research basis of the authors' histo-variogram using the standardized area index(SAI).A good attempt has been made to obtain the land type area information with higher resolution by merely using the spatial distribution characteristcs information of the land type in the image itself and further scaling-down in a given scale threshold on the basis of the existing spatial resolution data.

关键词： histo-variogram scaling-down scale effect LUCC

Changes in Typhoon Regional Heavy Precipitation Events over China from 1960 to 2018

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Advances in Atmospheric Sciences 2022年第2期39卷 272-283页

作者： Yangmei TIAN John LMCBRIDE Fumin REN guoping li Tian FENG College of Atmospheric Sciences Chengdu University of Information TechnologyChengdu 610225China State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China Honorary School of Earth ScienceUniversity of Melbourneand Research and Development DivisionBureau of MeteorologyMelbourneVIC 3010Australia Haikou Meteorological Observatory Haikou Meteorological BureauHaikou 570100China

In earlier studies,objective techniques have been used to determine the contribution of tropical cyclones to precipitation(TCP)in a region,where the Tropical cyclone Precipitation Event(TPE)and the Regional Heavy Precipitation Events(RHPEs)are defined and *** this study,TPE and RHPEs are combined to determine the Typhoon Regional Heavy Precipitation Events(TRHPEs),which is employed to evaluate the contribution of tropical cyclones to regional extreme precipitation *** on the Objective Identification Technique for Regional Extreme Events(OITREE)and the Objective Synoptic Analysis Technique(OSAT)to define TPE,temporal and spatial overlap indices are developed to identify the combined events as *** daily precipitation data and TC best-track data over the western North Pacific from 1960 to 2018,86 TRHPEs have been *** contribute as much as 20%of the RHPEs,but100%of events with extreme individual precipitation *** major TRHPEs continued for approximately a week after tropical cyclone landfall,indicating a role of post landfall *** frequency and extreme intensity of TRHPEs display increasing trends,consistent with an observed positive trend in the mean intensity of TPEs as measured by the number of daily station precipitation observations exceeding 100 mm and 250 *** frequent landfalling Southeast and South China TCs induced more serious impacts in coastal areas in the Southeast and the South during 1990-2018 *** roles of cyclone translation speed and"shifts"in cyclone tracks are examined as possible explanations for the temporal trends.

关键词： typhoon regional heavy precipitation events changes temporal and spatial characteristics

Preparation and characterization of Al/B/Fe_2O_3 nanothermites

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Science China Chemistry 2014年第6期57卷 797-802页

作者： SHEN lianHua li guoping LUO YunJun GAO Kun GE Zhen School of Materials and Engineering Beijing Institute of Technology

A sol-gel synthetic approach combined with an ultrasonic method was utilized to prepare Al/B/Fe2O3 *** structure and properties of the prepared nanothermites were characterized by thermogravimetric analysis,differential scanning calorimetry,scanning electron microscopy,X-ray diffraction,and an impact sensitivity *** results verified that the nano-aluminum and the micro-boron were uniformly dispersed in the pores of the iron oxide *** heat of the prepared Al/B/Fe2O3 nanothermites was 1.3 times that of the simple physically mixed *** addition,the heat of the combustion test showed that these materials were indeed ***-scale safe experiments also showed that the prepared materials through sol-gel were relatively insensitive to standard impact.

关键词： sol-gel nanothermites energetic materials properties

Therapeutic Effects of DNA Vaccine on Allergen-Induced Allergic Airway Inflammation in Mouse Model

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Cellular & Molecular Immunology 2006年第5期3卷 379-384页

作者： guoping li Zhigang liu Nanshan Zhong Bin liao Ying Xiong Inflammafion ＆ Allergic Diseases Research Unit Affiliated Hospital of Luzhou Medical College Luzhou 646000 Sichuan China College of life Sciences Shenzhen University Shenzhen 518060 China Guangzhou Institute of Respiratory Diseases Guangzhou Medical College Guangzhou 510120 China Department of Respiratory Disease Affiliated Hospital of Luzhou Medical College Luzhou 646000 China

Vaccination with DNA encoding Dermatophagoides pteronyssinus group 2 （Der p 2） allergen previously showed its effects of immunologic protection on Der p 2 allergen-induced allergic airway inflammation in mice. In present study, we investigated whether DNA vaccine encoding Der p 2 could exert therapeutic role on allergen-induced allergic airway inflammation in mouse model and explored the mechanism of DNA vaccination in asthma specific-allergen immunotherapy. After sensitized and challenged by Der p 2, the BALB/c mice were immunized with DNA vaccine. The degrees of cellular infiltration were scored. IgE levels in serum and IL-4/IL-13 levels in BALF were determined by EliSA. The lung tissues were assessed by histological examinations. Expressions of STAT6 and NF-kB in lung were determined by immunohistochemistry staining. Vaccination of mice with DNA vaccine inhibited the development of airway inflammation and the production of mucin induced by allergen, and reduced the level of Der p 2-specific IgE level. Significant reductions of eosinophil infiltration and levels of IL-4 and IL-13 in BALF were observed after vaccination. Further more, DNA vaccination inhibited STAT6 and NF-kB expression in lung tissue in Der p 2-immunized mice. These results indicated that DNA vaccine encoding Der p 2 allergen could be used for therapy of allergen-induced allergic airway inflammation in our mouse model. Cellular ＆ Molecular Immunology.

关键词： DNA vaccine Dermatophagoides pteronyssinus group 2 allergic airway inflammation

Handheld Raman Spectrometer for the Rapid Determination of Synthetic Cannabinoids

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Journal of Forensic Science and Medicine 2019年第1期5卷 29-32页

作者： ling Zhang guoping li Dalian Muicipal Public Security Bureau DalianChina Department of Criminal Technology Liaoning Police CollegeLiaoningChina

A handheld laser Raman spectrometer was developed to detect 11 synthetic cannabinoid *** spectrometer can be connected with a mobile phone by Bluetooth or a computer by a data *** Raman spectra of the synthetic cannabinoids AM‑694,JWH‑019,and nine others were accurately determined by software analysis of characteristic Raman *** technique is highly efficient,accurate,and simple,and it is a valid procedure for rapid on‑site investigations of cannabinoids.

关键词： Cannabinoids drugs Raman spectrometry

lincRNA1230 inhibits the differentiation of mouse ES cells towards neural progenitors

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Science China(life Sciences) 2016年第5期59卷 443-454页

作者： Chenxin Wang guoping li Yukang Wu Jiajie Xi Jiuhong Kang Clinical and Translational Research Center of Shanghai First Maternity and Infant Health Hospital Shanghai Key Laboratory of Signaling and Disease Research Collaborative Innovation Center for Brain Science School of Life Science and Technology Tongji University Shanghai 200092 China

In vitro, mouse embryonic stem （ES） cells can differentiate into many somatic cell types, including neurons and glial cells. When cultured in serum-free medium, ES cells convert spontaneously and efficiently to a neural fate. Previous studies have shown that the neural conversion of mouse ES cells includes both the participation of neural-specific transcription factors and the regulation of epigenetic modifications. However, the intracellular mechanism underlying this intrinsic transition still re- mains to be further elucidated. Herein, we describe a long intergenic non-coding RNA, lincRNA1230, which participates in the regulation of the neural lineage specification of mouse ES cells. The ectopic forced expression of lincRNAI230 dramatically inhibited mouse ES cells from adopting a neural cell fate, while lincRNA1230 knockdown promoted the conversion of mouse ES cells towards neural progenitors. Mechanistic studies have shown that lincRNA1230 inhibits the activation of early neural genes, such as Pax6 and Soxl, through the modulation of bivalent modifications （tri-methylation of histone3 lysine4 and his- tone3 lysine27） at the promoters of these genes. The interaction of lincRNA1230 with Wdr5 blocked the localization of Wdr5 at the promoters of early neural genes, thereby inhibiting the enrichment of H3K4me3 modifications at these loci. Collectively, these findings revealed a crucial role for lincRNA1230 in the regulation of the neural differentiation of mouse ES cells.

关键词： mouse ES cells neural differentiation long non-coding RNA (IncRNA) bivalent modification Wdr5