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Air Pollution Exposure Based on Nighttime Light Remote Sensing and Multi-source Geographic Data in Beijing

Chinese Geographical Science 2023年第2期33卷 320-332页

作者： zhang Zheyuan WANG Jia XIONG Nina liang Boyi WANG zong Beijing Forestry University Beijing Key Laboratory of Precision ForestryBeijing 100083China Beijing Forestry University Institute of GISRS&GPSBeijing 100083China Beijing Municipal Institute of City Management Beijing 100028China Beijing Key Laboratory of Municipal Solid Wastes Testing Analysis and Evaluation Beijing 100028China

Air pollution is a problem that directly affects human health,the global environment and the climate.The air quality index(AQI)indicates the degree of air pollution and effect on human health;however,when assessing air pollution only based on AQI monitoring data the fact that the same degree of air pollution is more harmful in more densely populated areas is ignored.In the present study,multi-source data were combined to map the distribution of the AQI and population data,and the analyze their pollution population exposure of Beijing in 2018 was analyzed.Machine learning based on the random forest algorithm was adopted to calculate the monthly average AQI of Beijing in 2018.Using Luojia-1 nighttime light remote sensing data,population statistics data,the population of Beijing in 2018 and point of interest data,the distribution of the permanent population in Beijing was estimated with a high precision of 200 m×200 m.Based on the spatialization results of the AQI and population of Beijing,the air pollution exposure levels in various parts of Beijing were calculated using the population-weighted pollution exposure level(PWEL)formula.The results show that the southern region of Beijing had a more serious level of air pollution,while the northern region was less polluted.At the same time,the population was found to agglomerate mainly in the central city and the peripheric areas thereof.In the present study,the exposure of different districts and towns in Beijing to pollution was analyzed,based on high resolution population spatialization data,it could take the pollution exposure issue down to each individual town.And we found that towns with higher exposure such as Yongshun Town,Shahe Town and Liyuan Town were all found to have a population of over 200000 which was much higher than the median population of townships of51741 in Beijing.Additionally,the change trend of air pollution exposure levels in various regions of Beijing in 2018 was almost the same,with the peak value being in winter and the lowest value being in

关键词： air quality index(AQI) population pollution exposure nighttime light remote sensing Luojia-1 random forest

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Digitalization of mechanical and physical properties of Singapore Bukit Timah granite rocks based on borehole data from four sites

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Underground Space 2021年第5期6卷 483-491页

作者： zhang Wengang Han liang zong Zixu zhang Yanmei Key Laboratory of New Technology for Construction of Cities in Mountain Area Chongqing UniversityChongqing 400045China College of Aerospace Engineering Chongqing UniversityChongqing 400044China School of Civil Engineering Chongqing UniversityChongqing 400045China

The Bukit Timah Granite(BTG)formation is widely distributed in the central and northern parts of Singapore Island.The BTG rocks in the formation vary from granite to granodiorite.Several hybrid rocks and dykes are also present in the BTG.The granite is in various states of fracturing and weathering,ranging from residual soils to intact,unweathered fresh rock.This paper presents some mechanical and physical properties of Singapore BTG rocks,based on data from the Factual Geotechnical Reports of more than 200 boreholes from Downtown Line stage II(DTL2)sites of Cashew,Hillview,Bukit Panjang and Beauty World.The variations of the parameters,including the unconfined compressive strength(UCS),the point-load strength index(I_(s50)),the Cerchar abrasivity index(CAI),and the slake-durability index are derived from laboratory tests on samples from borelogs of different depths.The empirical correlations between the UCS and I_(s50) and between the CAI and the strength parameters(UCS and I_(s50))are derived and validated against the commonly adopted equations.Statistical information,including the average values,the standard deviations,and the coefficients of variation,are provided for these parameters.These statistics provide a useful reference for numerical simulations and future projects involving BTG rocks.

关键词： BTG rocks Unconfined compressive strength Point-load strength index Digitalization Abrasivity Slake-durability

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Partial organic substitution weakens the negative effect of chemical fertilizer on soil micro-food webs

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Journal of Integrative Agriculture 2022年第10期21卷 3037-3050页

作者： LIU Han-wen zhang Xiao-ke zhang Gui-zong KOU Xin-chang liang Wen-ju Institute of Applied Ecology Chinese Academy of SciencesShenyang 110016P.R.China University of Chinese Academy of Sciences Beijing 100049P.R.China School of Geographical Science Northeast Normal UniversityChangchun 130024P.R.China

Soil biotic communities play vital roles in enhancing soil nutrient cycling and soil fertility.Long-term excessive nitrogen(N)application is disadvantageous to the stability of soil food webs and affects arable soil health and sustainable utilization.Proper organic substitution is essential to improve soil health and alleviate the disadvantages of excessive chemical fertilization.However,the biological effects of various organic amendments on soil micro-food webs are poorly understood.In order to explore the effects of various organic amendments including stover,biochar and manure on soil micro-food webs(microbial and nematode communities),a field plot experiment with maize having five treatments viz.,100%urea(100%N),70%urea(70%N),70%urea plus stover(Stover),70%urea plus cattle manure(Manure)and 70%urea plus biochar(Biochar)was conducted.Manure treatment increased the carbon(C)to N use efficiency of soil microbes,which contributed to the retention of soil C,while Biochar treatment elevated soil organic C(SOC)and soil p H.Additionally,Biochar treatment mitigated the negative effects of soil acidification on the soil micro-food web and reduced the abundance of plant parasites.Overall,the biological effect of organic amendments was distinguished from chemical fertilization(100%N and 70%N)through principal co-ordinates analysis.Negative relationships among soil properties,microbial and nematode biomass in the 100%N treatment were diminished in treatments where chemical fertilizer was reduced.The bottom-up effects on soil food webs were observed in organic substitution treatments.In conclusion,organic amendments improved soil fertility by regulating soil microbial and nematode communities in the cropland ecosystem,alleviated the negative effects of chemical fertilizer on the micro-food webs and controlled the trophic cascades among soil biota.

关键词： microbial community nematode community soil micro-food webs organic substitution chemical fertilizer soil health

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Planted forest is catching up with natural forest in China in terms of carbon density and carbon storage

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Fundamental Research 2022年第5期2卷 688-696页

作者： Boyi liang Jia Wang Zheyuan zhang Jia zhang Junping zhang Elizabeth L.Cressey zong Wang College of Forestry Beijing Forestry UniversityBeijing 100083China Precision Forestry Key Laboratory of Beijing Beijing Forestry UniversityBeijing 100083China Mapping and 3S Technology Center Beijing Forestry UniversityBeijing 100083China Geography College of Life and Environmental SciencesUniversity of ExeterExeterEX44RJUK

Over the last several decades,China has taken multiple measures for afforestation and natural forest protection,including setting the goal of carbon neutrality by the middle of 21th century.In order to support the practice of relevant policies from the scientific perspective,it is essential to precisely estimate the carbon storage of arbor forest,as it plays an important role in the carbon cycle of ecosystems.In this study,we first used the latest four phases of national forest inventory data to investigate the variation of carbon storage for both natural and planted arbor forest in China during the covered period(1999-2018).Then we used machine leaning methods to simulate the carbon density based on various kinds of environmental factors and analyzed the contribution of each influencing factor.Our results demonstrate that the total carbon storage for arbor forest in China kept increasing over the last two decades,but this increment was mainly brought about by the continuous expansion of forest land.The gap of carbon sequestration between natural forest and planted forest showed a significant trend of reduction.Additionally,tree age was identified as the dominant factor for influencing the spatiotemporal variation of carbon density among all the independent variables while the impact of climatic factor was limited.Therefore,the future improvement of carbon sequestration of arbor forest in should mainly rely on additional projects of afforestation,reforestation,green space conservation and reduction of emissions in China.Conclusions of this study have important implications for policy makers and other stakeholders to evaluate the previous achievement of environmental projects and can also help to set future plans and finally realize the goals of carbon neutrality.

关键词： National forestry inventory Forest stand volume Carbon storage Carbon density Machine learning

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Influence of hydrogen concentration on Fe_2O_3 particle reduction in fluidized beds under constant drag force

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International Journal of Minerals,Metallurgy and Materials 2015年第1期22卷 12-20页

作者： Lei Guo Han Gao Jin-tao Yu zong-liang Zhang Zhan-cheng Guo State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing

The fixed-gas drag force from a model calculation method that stabilizes the agitation capabilities of different gas ratios was used to explore the influence of temperature and hydrogen concentration on fluidizing duration, metallization ratio, utilization rate of reduction gas, and sticking behavior. Different hydrogen concentrations from 5vol%to 100vol%at 1073 and 1273 K were used while the drag force with the flow of N2 and H2 （N2：2 L·min^-1;H2：2 L·min^-1） at 1073 K was chosen as the standard drag force. The metallization ratio, mean reduc-tion rate, and utilization rate of reduction gas were observed to generally increase with increasing hydrogen concentration. Faster reduction rates and higher metallization ratios were obtained when the reduction temperature decreased from 1273 to 1073 K. A numerical relation among particle diameter, particle drag force, and fluidization state was plotted in a diagram by this model.

关键词： fluidized beds ferric oxide iron ores agglomeration hydrogen drag force

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Validation of Bacteroidales-based microbial source tracking markers for pig fecal pollution and their application in two rivers of North China

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Frontiers of Environmental Science & Engineering 2020年第4期14卷 139-146页

作者： Youfen Xu zong Li Ruyin Liu Hongxia liang Zhisheng Yu Hongxun zhang College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China

In China,pig feces is the predominant source of excrement produced b y animal husbandry.Improper use or direct discharge of pig feces can result in contamination of natural water systems.Microbial source tracking(MST)technology can identify the sources of fecal pollution in environmental water,and contribute to the management of pig fecal pollution by local environmental protection agencies.However,the accuracy of such assays can be context-dependent,and they have not been comprehensively evaluated under Chinese conditions.We aimed to compare the performance of five previously reported nig-specific MST assays(PF,Pig-Bac 1 STBR,Pig-Bac2 SYBR,Pig-1-Bac TaqMan,and Pig-2-Bac TaqMan,which are based on Bacteroidales 16S rRNA gene markers)and apply them in two rivers of North China.We collected a total of 173 fecal samples from pigs,cows,goats,chickens,humans,and horses across China.The PF assay optimized in this study showed outstanding qualitative performance and achieved 100%specificity and sensitivity.However,the two SYBR green qPCR assays(Pig-Bac1 SYBR and Pig-Bac2 SYBR)cross-reacted with most non-pig fecal samples.In contrast,both the Pig-l-Bac TaqMan and Pig-2-Bacr TaqMan assays gave 100%specificity and sensitivity.Of these,the Pig-2-Bac TaqMan assay showed higher reproducibility.Our results regarding the specificity of these pig-specific MST assays differ from those reported in Thailand,Japan,and America.Using the PF and Pig-2-Bac TaqMan assays,a field test comparing the levels of pig fecal pollution in rivers near a pig farm before and after comprehensive environmental pollution governance indicated that pig fecal pollution was effectively controlled at this location.

关键词： Microbial source tracking Pig fecal pollution 16S rRNA genem arkers Pig-specific Bacteroidales

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组织工程复合支架聚乳酸-羟基乙酸共聚物和羟基磷灰石纳米粒子接种自体骨髓间充质干细胞应用于骨再生（英文）

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2017年第11期18卷 963-976页

作者： Bing zhang Pei-biao zhang zong-liang WANG Zhong-wen LYU Han WU Department of Clinical Laboratory Second Hospital of Jilin UniversityChangchun 130041China Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Department of Radiology China-Japan Union Hospital of Jilin UniversityChangchun 130033China Department of Orthopedics China-Japan Union Hospital of Jilin UniversityChangchun 130033China

目的:对应用接枝的羟基磷灰石(g-HA)/聚乳酸-羟基乙酸共聚物(PLGA)纳米复合支架接种自体骨髓间充质干细胞(MSCs)和骨形态发生蛋白2(BMP-2)治疗重症骨缺损的新的治疗策略进行评估,并通过肌肉内移植研究人工骨的组织相容性和移植物在体内... 详细信息

目的:对应用接枝的羟基磷灰石(g-HA)/聚乳酸-羟基乙酸共聚物(PLGA)纳米复合支架接种自体骨髓间充质干细胞(MSCs)和骨形态发生蛋白2(BMP-2)治疗重症骨缺损的新的治疗策略进行评估,并通过肌肉内移植研究人工骨的组织相容性和移植物在体内的矿化和缺损骨的愈合。创新点:改性的PLGA接种自体MSCs的组织工程骨加速了骨缺损的愈合,使临床重症骨缺损的治疗有了新的手段。方法:应用溶剂浇铸和粒子沥滤方法将PLGA和g-HA制备成复合支架g-HA/PLGA。在g-HA/PLGA支架上接种兔自体MSCs制成组织工程移植物。取宽0.3 cm长2.0 cm的上述移植物埋入兔背部肌肉内,8周后取出移植物,使用扫描式电子显微镜(SEM)检测人工骨的组织相容性(图3a),X射线能量色散谱(EDX)分析钙浓度。然后,用锯锯掉兔前肢桡骨骨干2.0 cm,取同样长度的上述移植物放置于骨缺损处(图4)。术后2、4、8周应用计算机X线摄影(CR)检测骨缺损愈合情况(图5),组织学分析愈合组织结构(图6),SEM检测人工骨与周围组织的相容性(图7),反转录聚合酶链式反应(RT-PCR)检测愈合组织Collagen I、Collagen II和Bmp-2基因的表达。结论:PLGA掺入g-HA主要改善了矿化作用,有益于骨相关基因的表达和骨形成。自体MSCs的应用增强了骨形成和PLGA支架的矿化作用,并加速了支架的吸收。

关键词：纳米颗粒表面改性骨髓间充质干细胞生物矿化骨修复

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Analysis of debris flow control effect and hazard assessment in Xinqiao Gully,Wenchuan M_(s)8.0 earthquake area based on numerical simulation

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China Geology 2024年第2期7卷 248-263页

作者： Chang Yang Yong-bo Tie Xian-zheng zhang Yan-feng zhang Zhi-jie Ning zong-liang Li Chinese Academy of Geological Sciences Beijing 100037China Chengdu Center of China Geological Survey China Geological SurveyChengdu 610081China Technology innovation center for risk prevention and mitigation of geohazard Ministry of Natural ResourcesChengdu 611734China Observation and Research Station of Chengdu Geological Hazards Ministry of Natural ResourcesChengdu 610000China

Xinqiao Gully is located in the area of the 2008 Wenchuan M_(s)8.0 earthquake in Sichuan province,China.Based on the investigation of the 2023"6-26"Xinqiao Gully debris flow event,this study assessed the effectiveness of the debris flow control project and evaluated the debris flow hazards.Through field investigation and numerical simulation methods,the indicators of flow intensity reduction rate and storage capacity fullness were proposed to quantify the effectiveness of the engineering measures in the debris flow event.The simulation results show that the debris flow control project reduced the flow intensity by41.05%to 64.61%.The storage capacity of the dam decreases gradually from upstream to the mouth of the gully,thus effectively intercepting and controlling the debris flow.By evaluating the debris flow of different recurrence intervals,further measures are recommended for managing debris flow events.

关键词： Landslide Debris flow Hazard assessment Numerical simulation OpenLISEM Prevention and control project Wenchuan M_(s)8.0 earthquake Xinqiao Gully Sichuan province Geological hazards survey engineering

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Selective transmission and channel estimation in massive MIMO systems

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High Technology Letters 2016年第1期22卷 99-106页

作者：杨睿哲 zong liang Si Pengbo Ma Dawei zhang Yanhua Beijing Advanced Innovation Center for Future Internet Technology Beijing University of Technology College of Electronics Information and Control Engineering Beijing University of Technology

Massive MIMO systems have got extraordinary spectral efficiency using a large number of base station antennas,but it is in the challenge of pilot contamination using the aligned pilots.To address this issue,a selective transmission is proposed using time-shifted pilots with cell grouping,where the strong interfering users in downlink transmission cells are temporally stopped during the pilots transmission in uplink cells.Based on the spatial characteristics of physical channel models,the strong interfering users are selected to minimize the inter-cell interference and the cell grouping is designed to have less temporally stopped users within a smaller area.Furthermore,a Kalman estimator is proposed to reduce the unexpected effect of residual interferences in channel estimation,which exploits both the spatial-time correlation of channels and the share of the interference information.The numerical results show that our scheme significantly improves the channel estimation accuracy and the data rates.

关键词： MIMO系统信道估计传输过程小区间干扰时间相关性用户选择空间特征强干扰

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Association between the rs1042522 polymorphism in TP53 and prostate cancer risk:An updated meta-analysis

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Chronic Diseases and Translational Medicine 2017年第2期3卷 -页

作者： Song Fan zong-Yao Hao Meng zhang Chao-Zhao liang Department of Urology The First Affiliated Hospital of Anhui Medical UniversityHefeiAnhui 230022ChinaInstitute of UrologyAnhui Medical UniversityHefeiAnhui 230032China

Objective: The proposal of the present study was to investigate whether the TP53 rs1042522 polymorphism confers susceptibility to prostate cancer (PCa), by performing an updated meta-analysis. Methods: Eligible publications investigating the association between the TP53 rs1042522 polymorphism and PCa susceptibility were selected from PubMed, Google Scholar, and Web of Science. We used STATA 12.0 software to conduct the analyses. Odds ratio ( OR ) with 95% confidence interval ( CI ) was calculated. Results: A total of 17 case—control studies were retrieved reporting a total of 2683 cases and 2981 controls. However, no significant association was uncovered between the TP53 rs1042522 polymorphism and PCa susceptibility in the overall population under the five genetic models. In the stratification analysis by source of control, an increased susceptibility to PCa was identified in the population-based (P-B) group (CG vs. GG: OR = 1.48, 95% CI : 1.24—1.77, P < 0.01; CC/CG vs. GG: OR = 1.32, 95% CI : 1.12—1.57, P < 0.01), whereas a decreased susceptibility was uncovered in the hospital-based (H-B) group (CG vs. GG: OR = 0.67, 95% CI : 0.46—0.96, P = 0.03; CC/CG vs. GG: OR = 0.67, 95% CI : 0.46—0.99, P = 0.04) under heterozygous and dominant model. Conclusion: This study did not find an association between the TP53 rs1042522 polymorphism and PCa susceptibility in the overall population and corresponding subgroup analyses except in the stratification analysis by source of control. The results suggest that the TP53 rs1042522 polymorphism is not a risk factor for PCa.

关键词： rs1042522 Polymorphism Prostate cancer Meta-analysis

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