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Direct identification of total and missing OH reactivities from light-duty gasoline vehicle exhaust in China based on LP-LIF measurement

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Journal of environmental Sciences 2023年第11期133卷 107-117页

作者： Xuehui Liu Zibing Yuan Qing’e Sha Shengrong Lou Hongli Wang Xin Li Junyu Zheng Bin Yuan Min shao School of environment and energy South China University of TechnologyGuangzhou 510006China Institute of environmental and Climate Research Jinan UniversityGuangzhou 511443China State environmental Protection Key Laboratory of the Cause and Prevention of Urban Air Pollution Complex Shanghai Academy of Environmental SciencesShanghai 200233China College of environmental Science and engineering Peking UniversityBeijing 100871China

Considerable efforts have been devoted to characterising the chemical components of vehicle exhaust.However,these components may not accurately reflect the contribution of vehicle exhaust to atmospheric reactivity because of the presence of species not accounted for(“missing species”)given the limitations of analytical instruments.In this study,we improved the laser photolysis–laser-induced fluorescence(LP-LIF)technique and applied it to directly measure the total OH reactivity(TOR)in exhaust gas from light-duty gasoline vehicles in China.The TOR for China Ⅰ to Ⅵ-a vehicles was 15.6,16.3,8.4,2.6,1.5,and 1.6×10^(4) sec^(-1),respectively,reflecting a notable drop as emission standards were upgraded.The TOR was comparable between cold and warm starts.The missing OH reactivity(MOR)values for China Ⅰ to Ⅳ vehicles were close to zero with a cold start but were much higher with a warm start.The variations in oxygenated volatile organic compounds(OVOCs)under different emission standards and for the two start conditions were similar to those of the MOR,indicating that OVOCs and the missing species may have similar production processes.Online measurement revealed that the duration of the stable driving stage was the primary factor leading to the production of OVOCs and missing species.Our findings underscore the importance of direct measurement of TOR from vehicle exhaust and highlight the necessity of adding OVOCs and other organic reactive gases in future upgrades of emission standards,such that the vehicular contribution to atmospheric reactivity can be more effectively controlled.

关键词： Total OH reactivity LP-LIF Missing OH reactivity emission standard Light-duty gasoline vehicle

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VOC emission caps constrained by air quality targets based on response surface model:A case study in the Pearl River Delta Region,China

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Journal of environmental Sciences 2023年第1期123卷 430-445页

作者： Ya’nan Hu Bowen Shi Xin Yuan Chuanzeng Zheng Qing’e Sha Yufan Yu Zhijiong Huang Junyu Zheng Institute for environmental and Climate Research Jinan UniversityGuangzhou 511436China Guangdong Polytechnic of environmental Protection engineering Guangzhou 528216China

Because of the recent growth in ground-level ozone and increased emission of volatile organic compounds(VOCs),VOC emission control has become a major concern in China.In response,emission caps to control VOC have been stipulated in recent policies,but few of them were constrained by the co-control target of PM_(2.5)and ozone,and discussed the factor that influence the emission cap formulation.Herein,we proposed a framework for quantification of VOC emission caps constrained by targets for PM_(2.5)and ozone via a new response surface modeling(RSM)technique,achieving 50%computational cost savings of the quantification.In the Pearl River Delta(PRD)region,the VOC emission caps constrained by air quality targets varied greatly with the NOxemission reduction level.If control measures in the surrounding areas of the PRD region were not considered,there could be two feasible strategies for VOC emission caps to meet air quality targets(160μg/m^(3)for the maximum 8-hr-average 90th-percentile(MDA8-90%)ozone and 25μg/m^(3)for the annual average of PM_(2.5)):a moderate VOC emission cap withemission reductions or a notable VOC emission cap with>60%NOxemission reductions.If the ozone concentration target were reduced to 155μg/m^(3),deep NOxemission reductions is the only feasible ozone control measure in PRD.Optimization of seasonal VOC emission caps based on the Monte Carlo simulation could allow us to gain higher ozone benefits or greater VOC emission reductions.If VOC emissions were further reduced in autumn,MDA8-90%ozone could be lowered by 0.3-1.5μg/m^(3),equaling the ozone benefits of 10%VOC emission reduction measures.The method for VOC emission cap quantification and optimization proposed in this study could provide scientific guidance for coordinated control of regional PM_(2.5)and O_(3)pollution in China.

关键词： Volatile organic compounds emission caps Air quality targets Response surface model Monte Carlo(MC)simulations

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A meteorologically adjusted ensemble Kalman filter approach for inversing daily emissions:A case study in the Pearl River Delta,China

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Journal of environmental Sciences 2022年第4期34卷 233-248页

作者： Guanglin Jia Zhijiong Huang Xiao Tang Jiamin Ou Menghua Lu Yuanqian Xu Zhuangmin Zhong Qing’e Sha Huangjian Wu Chuanzeng Zheng Tao Deng Duohong Chen Min He Junyu Zheng School of environment and energy South China University of TechnologyUniversity Town CampusGuangzhou 510006China Institute for environmental and Climate Research Jinan UniversityGuangzhou 511486China Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100029China Faculty of Social and Behavioural Sciences Utrecht UniversityUtrechtCH 3584the Netherlands Guangzhou Institute of Tropical and Marine Meteorology China Meteorological AdministrationGuangzhou 510640China State environmental Protection Key Laboratory of Regional Air Quality Monitoring Guangdong Environmental Monitoring CenterGuangzhou 510308China Department of environmental Science and engineering College of Architecture and EnvironmentSichuan UniversityChengdu 610065China

The conventional ensemble Kalman filter(enKF),which is now widely used to calibrate emission inventories and to improve air quality simulations,is susceptible to simulation errors of meteorological inputs,making accurate updates of high temporal-resolution emission inventories challenging.In this study,we developed a novel meteorologically adjusted inversion method(MAeInv)based on the enKF to improve daily emission estimations.The new method combines sensitivity analysis and bias correction to alleviate the inversion biases caused by errors of meteorological inputs.For demonstration,we used the MAeInv to inverse daily carbon monoxide(CO)emissions in the Pearl River Delta(PRD)region,China.In the case study,60%of the total CO simulation biases were associated with sensitive meteorological inputs,which would lead to the overestimation of daily variations of posterior emissions.Using the new inversion method,daily variations of emissions shrank dramatically,with the percentage change decreased by 30%.Also,the total amount of posterior CO emissions estimated by the MAeInv decreased by 14%,indicating that posterior CO emissions might be overestimated using the conventional enKF.Model evaluations using independent observations revealed that daily CO emissions estimated by MAeInv better reproduce the magnitude and temporal patterns of ambient CO concentration,with a higher correlation coefficient(R,+37.0%)and lower normalized mean bias(NMB,-17.9%).Since errors of meteorological inputs are major sources of simulation biases for both low-reactive and reactive pollutants,the MAeInv is also applicable to improve the daily emission inversions of reactive pollutants.

关键词： emission inversion Daily emissions Meteorological adjustment ensemble Kalman filter

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Invasibility and recoverability of a plant community following invasion depend on its successional stages

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Soil ecology Letters 2022年第2期4卷 171-185页

作者： Hongwei Xu Zemin Ai qing Qu Minggang Wang Guobin Liu sha Xue State Key Laboratory of Soil erosion and Dryland Farming on Loess Plateau Institute of Soil and Water ConservationChinese Academy of Sciences and Ministry of Water ResourcesYangling 712100China College of Geomatics Xi'an University of Science and TechnologyXi'anShaanxi 710054China Institute of Soil and Water Conservation Northwest A&F UniversityYangling712100China University of Chinese Academy of Sciences Beijing 100049China Research Center of Forest Management engineering of State Forestry and Grassland Administration Beijing Forestry UniversityBeijing 100083China

exotic species invasion represent important causes of harming the structure,function,and ecological environment in ecosystems.Yet,knowledge remains limited on the invasibility(invasion advantage of exotic species)and recoverability(recovery ability of native species)of a plant community following invasion depend on its successional stages.We selected three grasses of Setaria viridis,Artemisia gmelinii,and Bothriochloa ischemum representing early(e),middle(M),and late(L)successional species,respectively.Meanwhile,the grasses of Panicum virgatum was selected to represent exotic species(invasion species).Three types of soil were collected to treat the three e,M,and L successional species,and one type of soil was collected to treat the exotic species.We compared the performance of the three native plant species and one exotic species grown in their“own”and“other”soils in a 2-year greenhouse experiment.Our study showed that exotic species performed better in soils of e and M successional species than in the soil of L successional species.After exotic species removed,e and M successional species exhibited poor growth in the soil of exotic species,while that of L successional species performed poor in field exotic species soils,but performed better in soils disturbed by exotic species.Our study demonstrated that the invasibility and recoverability of native plant communities changed with vegetation succession.

关键词： Invasion advantage Recovery advantage Plant growth exotic species Grass Greenhouse experiment

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Nonlinear extrapolation estimates of π

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Acta Mathematicae Applicatae Sinica 2024年第1期40卷 91-108页

作者： Wen-qing Xu sha-sha Wang Da-chuan Xu Beijing Institute for Scientific and engineering Computing Beijing University of TechnologyBeijing100124China Department of Mathematics and Statistics California State UniversityLong BeachCalifornia90840USA Department of Mathematics and Physics Shijiazhuang Tiedao UniversityShijiazhuang050043China

The classical Archimedean approximation of π uses the semiperimeter or area of regular polygons inscribed in or circumscribed about a unit circle in R~2 and it is well-known that by using linear combinations of these basic estimates,modern extrapolation techniques can greatly speed up the approximation process.Similarly,when n vertices are randomly selected on the circle,the semiperimeter and area of the corresponding random inscribed and circumscribing polygons are known to converge to π almost surely as n→∞,and by further applying extrapolation processes,faster convergence rates can also be achieved through similar linear combinations of the semiperimeter and area of these random polygons.In this paper,we further develop nonlinear extrapolation methods for approximating π through certain nonlinear functions of the semiperimeter and area of such polygons.We focus on two types of extrapolation estimates of the forms χ_n=S_n~αA_n~β and Y_n(p)=(αS_n~p+βA_n~p)~(1/p) where α+β=1,p≠0,and Sn and An respectively represents the semiperimeter and area of a random n-gon inscribed in the unit circle in R~2,and Xn may be viewed as the limit of Y_n(p) when p→0.By deriving probabilistic asymptotic expansions with carefully controlled error estimates for Xn and Y_n(p),we show that the choice α=4/3,β=-1/3 minimizes the approximation error in both cases,and their distributions are also asymptotically normal.

关键词： Archimedean polygons random polygons approximations ofπ extrapolation processes asymptotic convergence

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Treatment of urinary lithiasis following kidney transplantation with extracorporeal shock-wave lithotripsy

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Chinese Medical Journal 2011年第9期124卷 1431-1434页

作者： LI sha-dan WANG qing-tang CHeN Wei-guo Department of Urology General Hospital of Chengdu Military Command Chengdu Sichuan 610083 China

Background The incidence of urinary lithiasis following kidney transplantation is very low, and decision-supporting data are not available. The aim of this study was to review the diagnosis and treatment of urinary lithiasis following kidney transplantation, which is of realistic significance to reduce urinary lithiasis following kidney transplantation, prolong the survival of renal allografts.Methods The incidence, diagnosis and treatment of urinary lithiasis in ten patients following kidney transplantation were analyzed retrospectively. Seven out of these patients had stones sized approximately 0.4-1.1 cm, and they were treated with low-voltage, low-frequency extracorporeal shock-wave lithotripsy （eSWL）. Two patients had stones sized ＜0.3 cm and they underwent cystoscopy and ureteroscopy. The ureteral catheter endoscopes were inserted in a retrograde manner to mobilize stones repeatedly. After elimination of obstruction, a ureteral double J stent was indwelt.One patient had a pelvic stone （1.2 cm）, which was removed surgically.Results The major clinical manifestations were hematuria, oliguria or anuria. Some patients were asymptomatic and they were diagnosed through laboratory tests and imaging examinations, e.g., ultrasonography. After elimination of obstruction, subjective symptoms disappeared in all patients, and the function of renal allografts recovered. A six-month follow-up indicated no remnant stones or lithiasis relapse.Conclusions The diagnosis and treatment of renal allograft lithiasis are challenging. After prompt and appropriate treatment, the prognosis was satisfactory, and permanent renal functional impairment did not occur in most patients.

关键词： kidney transplantation lithiasis extracorporeal shock-wave lithotripsy

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GeNISTeIN INHIBITS PROLIFeRATION OF HUMAN eNDOMeTRIAL eNDOTHeLIAL CeLL IN VITRO

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Chinese Medical Sciences Journal 2008年第1期23卷 49-53页

作者： Gui-hua sha Shou-qing Lin Gynecological endocrinology Laboratory Peking Union Medical College HospitalDepartment of Obstetrics and GynecologyChinese Academy of Medical Sciences＆Peking Union Medical College Beijing 100730

Objective To explore the effect of genistein on proliferation of human endometrial endothelial cells(HeeCs)and glandular epithelium.Methods In vitro HeeCs and human endometrial cancer-1B cell(HeC-1B)were cultured with 0,1,10,50,100,and 200 μmol/L of genistein alone or indicated concentrations of genistein combined with 0.2 or 1 nmol/L 17β-estradiol(17β-e2).Cell proliferation was determined by[3H]-thymidine incorporation and cell cycle was measured by flow cytometry.Results After 96 hours of treatment,genistein inhibited the proliferation of HeeCs in a dose-dependent manner.The stimulation index reduced from 100%(without genistein treatment)to about 1%(200 μmol/L genistein).HeeCs were arrested at G1/0 and G2/M phase when treated with genistein for 96 hours.When the concentration of genistein was 200 μmol/L,the percentages of HeeCs at G1/0,G2/M,and S phase were 96.0%,2.1%,and 1.9%,respectively.However,when HeeCs were treated without genistein,the percentages of HeeCs at G1/0,G2/M,and S phase were 76.7%,8.5%,and 14.7%,respectively.17β-e2 could not influence the effects of genistein on the proliferation of HeeCs.Meanwhile,genistein could suppress the proliferation of HeC-1B.If the stimulation index of HeC-1B was defined as 100% when HeC-1B was treated with different doses of 17β-e2(without genistein),it was 67%,19%,as well as 32% when cell was supplemented with 200 μmol/L genistein combined with 0,0.2,or 1 nmol/L 17β-e2,respectively.Conclusion Genistein at the concentration of 200 μmol/L can sufficiently inhibit the proliferation of HeeCs and endometrial glandular epithelium simultaneously in vitro.

关键词：染料木黄酮子宫内膜细胞子宫内膜癌癌细胞增殖

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为何以及如何实施信息科技课程:教育数字化转型视野下的新思考

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中国电化教育 2024年第1期 59-67页

作者：吴砥郭庆朱莎华中师范大学国家数字化学习工程技术研究中心湖北武汉430079 华中师范大学人工智能教育学部湖北武汉430079

当前教育数字化转型的推进已经进入深水区,《义务教育信息科技课程标准(2022年版)》的出台肩负着促进学生数字素养提升,助力教育数字化转型的历史使命。文章深入分析教育数字化转型“转”什么的问题,挖掘了教育数字化转型的三个典型层面... 详细信息

当前教育数字化转型的推进已经进入深水区,《义务教育信息科技课程标准(2022年版)》的出台肩负着促进学生数字素养提升,助力教育数字化转型的历史使命。文章深入分析教育数字化转型“转”什么的问题,挖掘了教育数字化转型的三个典型层面:制度层面的创新、物质层面的升级以及人的素养的提升。进一步地探讨教育数字化转型怎么“转”的问题,构建了教育数字化转型的系统运行模型。在此基础上,分析了信息科技课程在教育数字化转型系统中的制度耦合价值、物质统整价值、素养发展价值。随后,在教育数字化转型系统中,审慎分析并指出当前信息科技课程的实施困境:在制度层面,政策理解与师资队伍发展不足;在物质层面,数字化软硬件设施与资源建设不完善;在人的层面,数字化教育实践意识与能力薄弱。最后,针对当前落实信息科技课程的困境,提出了针对性的实践策略:强化培训深度与广度,建立完善的信息科技教师培育机制;加快新教材建设步伐,完善课程内容和相关资源体系;重塑信息科技教育价值观,变革教学模式与方法;重视人机协同的教学实践,促进人机融合创新发展;落实“教—学—评”一致性,关注师生数字素养评价。

关键词：教育数字化转型信息科技课程实施数字素养

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Carbon dioxide adsorption behaviors of aluminum-pillared montmorillonite-supported alkaline earth metals

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Journal of environmental Sciences 2020年第12期32卷 109-117页

作者： Kai Wu qing Ye Runping Wu sha Chen Hongxing Dai Key Laboratory of Beijing on Regional Air Pollution Control Department of Environmental ScienceCollege of Environmental and Energy EngineeringBeijing University of TechnologyBeijing 100124China Beijing Key Laboratory for Green Catalysis and Separation Key Laboratory of Beijing on Regional Air Pollution ControlKey Laboratory of Advanced Functional MaterialsEducation Ministry of Chinaand Laboratory of Catalysis Chemistry and NanoscienceDepartment of Chemistry and Chemical EngineeringCollege of Environmental and Energy EngineeringBeijing University of TechnologyBeijing 100124China

The Al-pillared montmorillonite-supported alkaline earth metal 5M/Al-PILC(PILC = pillared clay, M = Mg, Ca, Sr, and Ba) and x Mg/Al-PILC( x = 1, 3, 5, and 7 wt.%) samples were prepared using an impregnation method. Physical properties of the materials were determined by means of X-ray diffraction(XRD) and N2 adsorption-desorption, and their CO2 adsorption behaviors were investigated using the thermogravimetric analyzer(TG), CO2 temperatureprogrammed desorption(CO2-TPD), and in situ diffuse reflectance infrared transform spectroscopy(in situ-DRIFTS) techniques. It is shown that 5 Mg/Al-PILC possessed the highest CO2 adsorption capacity(2.559 mmol/g). The characterization results indicate that Alpillaring increased the specific surface area of montmorillonite, which was beneficial for the adsorption of CO2. The CO2 adsorption process on the sample was mainly chemical adsorption, and alkalinity was the main factor influencing its adsorption capacity. The alkalinity of the sample was enhanced by loading an appropriate amount of alkaline earth metal, and the adsorbed CO2 was present in the form of bicarbonate and carbonate. In addition, the 5Mg/Al-PILC sample exhibited an excellent regeneration efficiency. We believe that the outcome of this research would provide a good option for developing highly effective CO2 adsorption materials.

关键词： Montmorillonite Al-pillaring Adsorbent CO2 adsorption Alkaline earth metal

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effect of percutaneous electrical stimulation at the Baliao point on preventing postpartum urinary retention after labor analgesia

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World Journal of Clinical Cases 2024年第16期12卷 2758-2764页

作者： Xiao-qing Wang Li-sha Guan Department of Obstetrics and Gynecology Suzhou Ninth Affiliated Hospital of Suzhou UniversitySuzhou 215200Jiangsu ProvinceChina

BACKGROUND Anesthetic drugs used in labor analgesia also paralyze the bladder muscle by blocking the sacral plexus,thereby affecting maternal postpartum spontaneous urination and increasing the risk of postpartum urinary retention(PUR).AIM To analyze the effect of percutaneous electrical stimulation at the Baliao point combined with biofeedback therapy for PUR prevention.MeTHODS We selected 182 pregnant women who received labor analgesia in obstetrics between June 2022 and December 2023.They were divided into the combined therapy group(transcutaneous electrical stimulation of the Baliao point combined with biofeedback therapy)and the control group(biofeedback therapy alone).The first spontaneous urination time,first postpartum urine volume,bladder residual urine volume,postpartum hemorrhage volume,pre-urination waiting time,PUR incidence,adverse reactions,and the intervention’s clinical efficacy were compared between the two groups.ReSULTS The first spontaneous urination time after delivery was more delayed(2.92±1.04 h vs 3.61±1.13 h,Pewer initial postpartum urine(163.54±24.67 mL vs 143.72±23.95 mL,Pe residual bladder urine(54.81±10.78 mL vs 65.25±13.52 mL,Pe postpartum bleeding(323.15±46.95 mL vs 348.12±45.03 mL,P=0.001),and longer waiting time for urination(0.94±0.31 min vs 1.29±0.42 min,Pe control group than in the combined therapy group.The control group also had higher PUR incidence(4.65%vs 15.85%,P=0.016).Both groups had no adverse reactions,but the clinical total efficacy rate of the intervention was significantly higher in the combined therapy group than in the control group(95.35%vs 84.15%,P=0.016).CONCLUSION Percutaneous electrical stimulation of the Baliao point combined with biofeedback can significantly promote postpartum micturition of parturients with labor analgesia,thereby effectively preventing PUR occurrence.

关键词： Transcutaneous electrical stimulation Baliao acupoint Biofeedback Pain relief during childbirth Postpartum uroschesis

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