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| 1 | Nitrous oxide emissions from a maize field during two consecutive growing seasons in the North China Plain显示文摘Nitrous oxide (N 2 O) emissions from a maize field in the North China Plain (Wangdu County,Hebei Province,China) were investigated using static chambers during two consecutive maize growing seasons in the 2008 and 2009.The N 2 O pulse emissions occurred with duration of about 10 days after basal and additional fertilizer applications in the both years.The average N 2 O fluxes from the CK (control plot,without crop,fertilization and irrigation),NP (chemical N fertilizer),SN (wheat straw returning plus chemical N fertilizer),OM- 1/2N (chicken manure plus half chemical N fertilizer) and OMN (chicken manure plus chemical N fertilizer) plots in 2008 were 8.51,72.1,76.6,101,107 ng N/(m 2 ·sec),respectively,and in 2009 were 33.7,30.0 and 35.0 ng N/(m 2 ·sec) from CK,NP and SN plots,respectively.The emission factors of the applied fertilizer as N 2 O-N (EFs) were 3.8% (2008) and 1.1% (2009) for the NP plot,3.2% (2008) and 1.2% (2009) for the SN plot,and 2.8% and 2.2% in 2008 for the OM-1/2N and OMN plots,respectively.Hydromorphic properties of the investigated soil (with gley) are in favor of denitrification.The large differences of the soil temperature and water-filled pore space (WFPS) between the two maize seasons were suspected to be responsible for the significant yearly variations.Compared with the treatments of NP and SN,chicken manure coupled with compound fertilizer application significantly reduced fertilizer loss rate as N 2 O-N. | Yuanyuan Zhang Junfeng Liu Yujing Mu Zhu Xu Shuwei Pei Xiaoxiu Lun Ying Zhang | 2012 | Journal of Environmental Sciences2012，24，1： | 15 |
| 2 | Seasonal and diurnal variations of atmospheric peroxyacetyl nitrate, peroxypropionyl nitrate, and carbon tetrachloride in Beijing显示文摘Atmospheric peroxyacetyl nitrate(PAN), peroxypropionyl nitrate(PPN), and carbon tetrachloride(CCl4) were measured from September 2010 to August 2011 in Beijing. PAN exhibited low values from mid-autumn to early spring(October to March) with monthly average concentrations ranging from 0.28 to 0.73 ppbV, and increased from early spring to summer(March to August), ranging from 1.37–3.79 ppbV. The monthly variation of PPN was similar to PAN, with low values(below detection limit to 0.18 ppbV) from mid-autumn to early spring, and a monthly maximum in September(1.14 ppbV). The monthly variation of CCl4was tightly related to the variation of temperature, exhibiting a minimum in winter(69.3 pptV) and a maximum of 180.6 pptV in summer. Due to weak solar intensity and short duration, PAN and O3showed no distinct diurnal patterns from morning to night during winter, whereas for other seasons, they both exhibited maximal values in the late afternoon(ca. 15:00 to 16:00 local time) and minimal values during early morning and midnight. Good linear correlations between PAN and PPN were found in autumn(R = 0.91), spring(R = 0.94), and summer(R = 0.81), with slopes of 0.130, 0.222, and 0.133, respectively, suggesting that anthropogenic hydrocarbons dominated the photochemical formation of PANs in Beijing. Positive correlation between PAN and O3 in summer with the low slopes( O3 / PAN) ranging from 9.92 to 18.0 indicated serious air pollution in Beijing, and strong negative correlation in winter reflected strong O3consumption by NO titration and less thermal decompositin of PAN. | Gen Zhang Yujing Mu Junfeng Liu Chenglong Zhang Yuanyuan Zhang Yujie Zhang Hongxing Zhang | 2014 | Journal of Environmental Sciences2014，26，1： | 11 |
| 3 | High-Temperature Metamorphism, Anataxis and Tectonic Evolution of a Mafic Granulite from the Eastern Himalayan Orogen显示文摘The Himalayan Orogen, resulting from the Tertiary collision of Indian and Asian continents, is a natural laboratory for studying metamorphism, partial melting and granite formation of collisional orogens. However, metamorphic and anatectic conditions and timescales of meta-mafic rocks in the Greater Himalayan Sequences(GHS) in the east-central Himalaya remain controversial. In this paper, we conduct a study of petrology and geochronology of mafic granulite from the Eastern Himalayan Syntaxis(EHS). The mafic granulite with abundant leucosome bands occurs as layers within felsic granulites and is well deformed. The granulite consists of garnet, plagioclase, amphibole and quartz with minor clinopyroxene, orthopyroxene, biotite, rutile, titanite and ilmenite. The garnet has growth compositional zoning and contains abundant mineral inclusions in its core. Peak metamorphic mineral assemblage of the granulite is garnet, amphibole, plagioclase, quartz, clinopyroxene and rutile, recording a high-pressure(HP) and high-temperature(HT) peak-metamorphism under conditions of 14–15.5 kbar and 780–790℃ in the presence of melt. The reconstructed clockwise P-T path is characterized by an early heating and burial prograde metamorphism, and late isothermal and cooling decompression retrogression. The granulite witnessed a long lasting HT metamorphism, partial melting and melt crystallization process which began at ca. 39 Ma and lasted to ca. 11 Ma. The present study shows that various high-grade rocks of the GHS in the EHS core experienced similar metamorphic conditions and P-T-t paths, indicating that they occurred as a coherent slab during the subduction and exhumation of Indian lithosphere. The significant melts generated during the prograde metamorphism of the GHS rocks not only contributed to the formation of the Himalayan leucogranite, but also resulted in the rheological weakening and ductile flow of the thickened lower crust of the Himalayan Orogen. | Zeming Zhang Huixia Ding Xin Dong Zuolin Tian Dongyan Kang Hongchen Mu Shengkai Qin Yuanyuan Jiang Mengmei Li | 2018 | Journal of Earth Science2018，29，5： | 7 |
| 4 | Quality prediction of freshly-harvested wheat using Gluto Peak during postharvest maturation显示文摘Much recent researches have demonstrated that the quality of freshly-harvested wheat could be improved during postharvest maturation by determinating the rheological properties.However,this process is time-consuming and complex.This study aimed to provide a rapid and convenient method for predicting wheat quality during postharvest maturation by use of Gluto Peak device.Farinograph and Extensograph were used to determine the rheological properties of four wheat samples(WT1,WT2,WT3,WT4)stored under different conditions(WT1:15℃,50%RH;WT2:20℃65%RH;WT3:28℃75%RH;WT4:35℃85%RH)for a total of 10 weeks,and Gluto Peak test was used to determine the gluten aggregation properties of the four samples.Correlation analysis was also conducted between the rheological properties and the gluten aggregation properties.Results of rheological properties showed that all Extensographic properties(dough extensibility,resistance,maximum resistance and area)of the four samples increased along with the storage time,and the Farinographic properties(water absorption,dough development time,dough stability time,and farinograph quality number(FQN))had the same tendency,indicating that the rheological properties were improved considerably with storage time extending.The Gluto Peak curves revealed that Peak Maximum Time(PMT),Brabender Equivalents Maximum(BEM)and Energy to Maximum Torque(En MT)of wheat flour of the four samples varied greatly,particularly the PMT and En MT of the samples WT3 and WT4 increased remarkably.Results of correlation analysis showed that En MT had significant correlation with water absorption and area(P<0.05)for sample WT1,and also showed significant correlation with dough development time(P<0.05)for sample WT2.For sample WT3,PMT was significantly correlated with the dough development time,extensibility,area(P<0.05),and FQN(P<0.01);and En MT was in significant correction with water absorption(P<0.01),and dough stability time,FQN,extensibility,maximum resistance and area(P<0.05).For sample WT4,both PMT and En MT had significant correction with area(P<0.05).The study indicated that the Gluto Peak test is effective in quality prediction for the freshly-harvested wheat during postharvest maturation,making it possible to realize rapid wheat quality detection and evaluation in storage period. | Mengyu Mu Ruidie Geng Yuanyuan Yue Feng Jia Xia Zhang Jinshui Wang | 2021 | Grain & Oil Science and Technology2021，4，4： | 5 |
| 5 | Impact of dicyandiamide on emissions of nitrous oxide,nitric oxide and ammonia from agricultural field in the North China Plain显示文摘Nitrous oxide(N_2O), nitric oxide(NO) and ammonia(NH_3) emissions from an agricultural field in the North China Plain were compared for three treatments during a whole maize growing period from 26 June to 11 October, 2012. Compared with the control treatment(without fertilization, designated as CK), remarkable pulse emissions of N_2O, NO and NH_3 were observed from the normal fertilization treatment(designated as NP) just after fertilization, whereas only N_2O and NH_3 pulse emissions were evident from the nitrification inhibitor treatment(designated as ND). The reduction proportions of N_2O and NO emissions from the ND treatment compared to those from the NP treatment during the whole maize growing period were 31% and 100%, respectively. A measurable increase of NH_3 emission from the ND treatment was found with a cumulative NH_3 emission of 3.8 ± 1.2 kg N/ha,which was 1.4 times greater than that from the NP treatment(2.7 ± 0.7 kg N/ha). | Yizhen Zhou Yuanyuan Zhang Di Tian Yujing Mu | 2016 | Journal of Environmental Sciences2016，28，2： | 4 |
| 6 | Recent developments and consideration issues in solid adsorbents for CO_2 capture from flue gas显示文摘The increase in energy demand caused by industrialization leads to abundant CO_2 emissions into atmosphere and induces abrupt rise in earth temperature. It is vital to acquire relatively simple and cost-effective technologies to separate CO_2 from the flue gas and reduce its environmental impact. Solid adsorption is now considered an economic and least interfering way to capture CO_2, in that it can accomplish the goal of small energy penalty and few modifications to power plants. In this regard, we attempt to review the CO_2 adsorption performances of several types of solid adsorbents, including zeolites, clays, activated carbons, alkali metal oxides and carbonates, silica materials, metal–organic frameworks, covalent organic frameworks, and polymerized high internal phase emulsions. These solid adsorbents have been assessed in their CO_2 adsorption capacities along with other important parameters including adsorption kinetics, effect of water, recycling stability and regenerability. In particular,the superior properties of adsorbents enhanced by impregnating or grafting amine groups have been discussed for developing applicable candidates for industrial CO_2 capture. | Lijuan Nie Yuanyuan Mu Junsu Jin Jian Chen Jianguo Mi | 2018 | Chinese Journal of Chemical Engineering2018，26，11： | 4 |
| 7 | High Spatial Resolution and High Temporal Frequency(30-m/15-day) Fractional Vegetation Cover Estimation over China Using Multiple Remote Sensing Datasets:Method Development and Validation显示文摘High spatial resolution and high temporal frequency fractional vegetation cover(FVC) products have been increasingly in demand to monitor and research land surface processes. This paper develops an algorithm to estimate FVC at a 30-m/15-day resolution over China by taking advantage of the spatial and temporal information from different types of sensors: the 30-m resolution sensor on the Chinese environment satellite(HJ-1) and the 1-km Moderate Resolution Imaging Spectroradiometer(MODIS). The algorithm was implemented for each main vegetation class and each land cover type over China. First, the high spatial resolution and high temporal frequency normalized difference vegetation index(NDVI) was acquired by using the continuous correction(CC) data assimilation method. Then, FVC was generated with a nonlinear pixel unmixing model. Model coefficients were obtained by statistical analysis of the MODIS NDVI. The proposed method was evaluated based on in situ FVC measurements and a global FVC product(GEOV1 FVC). Direct validation using in situ measurements at 97 sampling plots per half month in 2010 showed that the annual mean errors(MEs) of forest, cropland, and grassland were-0.025, 0.133, and 0.160, respectively, indicating that the FVCs derived from the proposed algorithm were consistent with ground measurements [R2 = 0.809,root-mean-square deviation(RMSD) = 0.065]. An intercomparison between the proposed FVC and GEOV1 FVC demonstrated that the two products had good spatial–temporal consistency and similar magnitude(RMSD approximates 0.1). Overall, the approach provides a new operational way to estimate high spatial resolution and high temporal frequency FVC from multiple remote sensing datasets. | Xihan MU Tian ZHAO Gaiyan RUAN Jinling SONG Jindi WANG Guangjian YAN Tim RMCVICAR Kai YAN Zhan GAO Yaokai LIU Yuanyuan WANG | 2021 | Journal of Meteorological Research2021，35，1： | 3 |
| 8 | Identification of stromal differentially expressed proteins in the colon carcinoma by quantitative proteomics显示文摘 | Yibing Mu Yongheng Chen Guiying Zhang Xianquan Zhan Yuanyuan Li Ting Liu Guoqing Li Maoyu Li Zhefeng Xiao Xiaoxiang Gong Zhuchu Chen | 2013 | ELECTROPHORESIS2013，，11： | 1 |
| 9 | Activity maintenance of the excised branches and a case study of NO_2 exchange between the atmosphere and P.nigra branches显示文摘The efficient maintenance of the activity of excised branches is the powerful guarantee to accurately determine gas exchange flux between the detached branches of tall trees and the atmosphere. In this study, the net photosynthetic rate(NPR) of the excised branches and branches in situ were measured simultaneously by using two photosynthetic instruments to characterize the activity of the excised branches of Phyllostachys nigra. The ratio of normalized NPR of excised branches to NPR in situ was used to assess the photosynthetic activity of detached branches. Based on photosynthetic activity, an optimal hydroponics protocol for maintaining activity of excised P. nigra branches was presented:1/8 times the concentration of Gamborg B5 vitamin mixture with p H = 6. Under the best cultivation protocol, photosynthetic activity of excised P. nigra branches could be maintained more than 90% within 6 hr in the light intensity range of 200–2000 μmol/(m2·sec) and temperature range of 13.4–28.7°C. The nitrogen dioxide(NO2) flux differences between in situ and in vitro branches and the atmosphere were compared using double dynamic chambers.Based on the maintenance method of excised branches, the NO2 exchange flux between the excised P. nigra branches and the atmosphere(from-1.01 to-2.72 nmol/(m2·sec) was basically consistent with between the branches in situ and the atmosphere(from-1.12 to-3.16 nmol/(m2 sec)) within 6 hr. Therefore, this study provided a feasible protocol for in vitro measurement of gas exchange between tall trees and the atmosphere for a period of time. | Chun Chen Yuzheng Wang Yuanyuan Zhang Xiaoxiu Lun Chengtang Liu Yujing Mu Chenglong Zhang Pengfei Liu Chaoyang Xue Min Song Can Ye Junfeng Liu | 2019 | Journal of Environmental Sciences2019，31，6： | 1 |
| 10 | An improved GC-ECD method for measuring atmospheric N_2O显示文摘Gas chromatography equipped with an electron capture detector (GC-ECD) has been widely used for measuring atmospheric N2O,but nonlinear response and the influence of atmospheric CO2 have been recognized as defects for quantification.An original GCECD method using N 2 as carrier gas was improved by introducing a small flow rate of CO2 makeup gas into the ECD,which could well remedy the above defects.The N2O signal of the improved method was 4-fold higher than that of the original method and the relative standard deviation was reduced from > 1% to 0.31%.N2O concentrations with different CO2 concentrations (172.2×10-6-1722×10-6mol/mol) measured by the improved GC-ECD method were in line with the actual N2O concentrations.However,the N2O concentrations detected by the original method were largely biased with a variation range of-4.5%~7%.The N2O fluxes between an agricultural field and the atmosphere measured by the original method were greatly overestimated in comparison with those measured by the improved method.Good linear correlation (R2=0.9996) between the response of the improved ECD and N2O concentrations (93×10-9-1966×10-9mol/mol) indicated that atmospheric N2O could be accurately quantified via a single standard gas.Atmospheric N2O concentrations comparatively measured by the improved method and a high precision GC-ECD method were in good agreement. | Yuanyuan Zhang Yujing Mu Shuangxi Fang Junfeng Liu | 2013 | Journal of Environmental Sciences2013，25，3： | 1 |
| 11 | Propelling polysulfide redox by Fe_(3)C-FeN heterostructure@nitrogendoped carbon framework towards high-efficiency Li-S batteries显示文摘Lithium-sulfur(Li-S) batteries hold great promise in next-generation high-energy-density energy storage systems,but the intractable shuttle effect and the sluggish redox kinetics of polysulfides hinder the practical implementation of Li-S batteries.Here,heterostructured Fe_(3)C-FeN nanoparticles dotted in the threedimensional-ordered nitrogen-doped carbon framework(Fe_(3)C-FeN@NCF) were synthesized by molecular engineering combined with heterointerface engineering,and were applied to regulate the immobilization-diffusion-conversion behavior of polar polysulfides.It is experimentally and theoretically demonstrated that the heterointerface between Fe_(3)C and FeN exhibits high sulfiphilicity and high electronic/ionic conductivity,thus effectively capturing polysulfides and accelerating the bidirectional conversion of sulfur species.Meanwhile,the holey carbon framework functions as the scaffold to highly disperse binary nanoparticles,ensuring the sufficient exposure of active sites and the easy accessibility for lithium ions and electrons.By virtue of these synergistic merits,the Li-S batteries based on Fe_(3)CFeN@NCF-modified separators afford excellent electrochemical performances including a high rate capacity of 858 mA h g^(-1)at 2 C and a low capacity decay rate of 0.07% per cycle after 800 cycles at 1C This work provides inspiration for the design of heterostructured compounds and sheds light on the potential of heterostructure in high-efficiency Li-S batteries. | Mengdi Zhang Jiawei Mu Yanan Li Yuanyuan Pan Zhiliang Dong Bei Chen Shiwei Guo Wenhan Yuan Haiqiu Fang Han Hu Mingbo Wu | 2023 | Journal of Energy Chemistry2023，，3： | 1 |
| 12 | Detecting Regional Deep Ocean Warming below 2000 Meter Based on Altimetry,GRACE,Argo,and CTD Data显示文摘The deep ocean below 2000 m is a large water body with the sparsest data coverage,challenging the closure of the sea-level budget and the estimation of the Earth’s energy imbalance.Whether the deep ocean below 2000 m is warming globally has been debated in the recent decade.However,as the regional signals are generally larger than the global average,it is intriguing to investigate the regional temperature changes.Here,we adopt an indirect method that combines altimetry,GRACE,and Argo data to examine the global and regional deep ocean temperature changes below 2000 m.The consistency between high-quality conductivity-temperature-depth(CTD)data from repeated hydrographic sections and our results confirms the validity of the indirect method.We find that the deep oceans are warming in the Middle East Indian Ocean,the subtropical North and Southwest Pacific,and the Northeast Atlantic,but cooling in the Northwest Atlantic and Southern oceans from 2005 to 2015. | Yuanyuan YANG Min ZHONG Wei FENG Dapeng MU | 2021 | Advances in Atmospheric Sciences2021，38，10： | 1 |
| 13 | Characteristics and anthropogenic sources of carbonyl sulfide in Beijing显示文摘Atmospheric mixing ratios of carbonyl sulfide(COS) in Beijing were intensively measured from March 2011 to June 2013. COS mixing ratios exhibited distinct seasonal variation, with a maximum average value of 849 ± 477 pptv in winter and a minimal value of 372 ± 115 pptv in summer. The seasonal variation of COS was mainly ascribed to the combined effects of vegetation uptake and anthropogenic emissions. Two types of significant linear correlations(R2> 0.66) were found between COS and CO during the periods from May to June and from October to March, with slopes(ΔCOS/ΔCO) of 0.72 and 0.14 pptv/ppbv, respectively. Based on the emission ratios of COS/CO from various sources, the dominant anthropogenic sources of COS in Beijing were found to be vehicle tire wear in summer and coal burning in winter. The total anthropogenic emission of COS in Beijing was roughly estimated as 0.53 ± 0.02 Gg/year based on the local CO emission inventory and the ΔCOS/ΔCO ratios. | Ye Cheng Chenglong Zhang Yuanyuan Zhang Hongxing Zhang Xu Sun Yujing Mu | 2015 | Journal of Environmental Sciences2015，27，2： | 1 |
| 14 | Characteristics and sources of peroxyacetyl nitrate(PAN)in the rural North China Plain:Results from1-year continuous observations显示文摘Peroxyacetyl nitrate(PAN)is an important photochemical pollutant in the troposphere,whereas long-term measurements are scarce in rural areas in North China Plain(NCP),resulting in unclear seasonal variations and sources of PAN in rural NCP.In this study,we conducted a 1-year observation of PAN during 2021-2022 at the rural NCP site.The average concentrations of PAN were 1.10,0.75,0.65,and 0.88 ppbv in spring,summer,autumn,and winter,respectively,with a 1-year average of 0.81±0.60 ppbv.Calculations indicate that the loss of PAN through thermal decomposition in summer accounts for 43.2% of the total formed PAN,which is an important reason for the low concentration of PAN in summer.We speculate that since the correlation between PAN and O_(3) in winter is significantly lower than that in other seasons,the observed regional transport of PAN cannot be ignored in winter.Through budget analysis,regional transport accounted for 12.8% and 55.9% of the observed PAN on the spring and winter pollution days,respectively,which showed that regional transport played key roles during the photochemical pollution of the rural NCP in winter.The potential source contribution function revealed that the transported PAN mainly comes from southern Hebei in spring.In winter,the transported PAN was mainly from Langfang,Hengshui,and southern Beijing.Our findings may aid in understanding PAN variations in different seasons in rural areas and highlight the impact of regional transport on the PAN budget. | Xin Liu Xiaowei He Chenglong Zhang Yifei Song Shuyang Xie Chengtang Liu Pengfei Liu Yuanyuan Zhang Yujing Mu Junfeng Liu | 2024 | Journal of Environmental Sciences2024，，4： | 0 |
| 15 | Seepage-Stress-Damage Coupled Model of Coal Under Geo-Stress Influence显示文摘In the seepage-stress-damage coupled process,the mechanical properties and seepage characteristics of coal are distinctly different between pre-peak stage and post-peak stage.This difference is mainly caused by damage of coal.Therefore,in the process of seepage and stress analysis of coal under the influence of excavation or mining,we need to consider the weakening of mechanical properties and the development of fractures of damaged coal.Based on this understanding,this paper analyzes the influence of damage on mechanics and seepage behavior of coal.A coupled model is established to analyze the seepage-stress-damage coupled process of coal.This model implemented into COMSOL and MATLAB software to realize the numerical solving.Two examples are adopted to verify the correctness of the model and some useful conclusions are obtained.The numerical model establishes the relationship between microcosmic damage evolution and macroscopical fracture and simulates the whole process of coal from microcosmic damage to macroscopical fracture,and the dynamic simulation of fluid flow in this process.It provides a numerical tool for further research on the seepage-stress-damage analysis. | Yi Xue Faning Dang Rongjian Li Liuming Fan Qin Hao Lin Mu Yuanyuan Xia | 2018 | Computers, Materials & Continua2018，，1： | 0 |
| 16 | Analysis of Subcellular Localization and Pathogenicity of Plum Bark Necrosis Stem-Pitting Associated Virus Protein P6显示文摘Infection of plum bark necrosis stem pitting associated virus(PBNSPaV)has been reported in many Prunus species in several countries,causing significant economic losses.The very small proteins encoded by plant viruses are often overlooked due to their short sequences and uncertain significance.However,numerous studies have indicated that they might play important roles in the pathogenesis of virus infection.The role of small hydrophobic protein P6,encoded by the open reading frame 2 of PBNSPaV,has not been well explored.In this study,we amplified the P6 fragment from a PBNSPaV isolate by RT-PCR using specific primers and found that it is 174 bp long and encodes a protein of approximately 6.3 kD with a transmembrane domain.Subcellular localization analysis of P6 proteins in tobacco leaves showed that P6 localizes to the cytomembrane and nuclear membrane.To further clarify the pathogenicity of P6 proteins,we constructed a PVX-P6 expression vector by inserting the p6 fragment into a potato virus X(PVX)-based vector and transformed it into Agrobacterium tumefaciens GV3101.Infiltration of Nicotiana benthamiana(N.benthamiana)with the PVX vector-transformed A.tumefaciens led to slight mosaic symptoms at 14 days of post-inoculation.Meanwhile,infiltration with the PVX-P6 vector-transformed A.tumefaciens resulted in no significant symptoms.These results demonstrated that heterologous expression of P6 in N.benthamiana could not enhance the pathogenicity of PVX.Our study indicates that P6 may not be a potential pathogenic factor associate with the causing of symptoms,and the mode of action of PBNSPaV-P6 protein remains to be further studied. | Yuanyuan Li Jinze Mu Qingliang Li Huabing Liu Xuefeng Yuan Deya Wang | 2023 | Phyton-International Journal of Experimental Botany2023，92，7： | 0 |
| 17 | Characteristics and influence factors of NO2 exchange flux between the atmosphere and P. nigra显示文摘Nitrogen dioxide(NO2)is an important substance in atmospheric photochemical processes and can also be absorbed by plants.N02 fluxes between the atmosphere and P.nigrc seedlings were investigated by a double dynamic chambers method in Beijing from June 15to September 3,2017.The range of N02 exchange fluxes between P.nigra seedlings and the atmosphere was from-14.6 to 0.8 nmol/(m2.sec)(the positive data represent N02 emissior from trees,while the negative values indicate absorption).Under ambient concentrations the mean NO2 flux during the fast-growing stage(Jun.15-Aug.4)was-3.0 nmol/(m2·sec)greater than the flux of-1.5 nmol/(m2-sec)during the later growth stage(Aug.8-Sept.3)The daily exchange fluxes of NO2 obviously fluctuated.The fluxes were largest in the morning and decreased gradually over time.Additionally,the N02 fluxes were larger undei high light intensities than under low light intensities during the whole growth period.The effects of temperature on N02 fluxes were different under two growth periods.The NO2exchange fluxes were larger in a range of temperatures close to 44℃in the fast-growing stage,whereas there were no evident differences in N02 exchange fluxes under widel differing temperatures in the later growth stage.Under polluted conditions,the uptake ability of N02 was weakened.Additionally,the compensation point of N02 was 5.6 ppb ir the fast-growing stage,whereas it was 1.4 ppb in the later growth stage.The depositior velocities of NO2 were between 0.3 and 2.4 mm/sec. | Chun Chen Yuzheng Wang Yuanyuan Zhang Chengtang Liu Xiaoxiu Lun Yujing Mu Chenglong Zhang Junfeng Liu | 2019 | Journal of Environmental Sciences2019，31，10： | 0 |
| 18 | Clinical Epidemiology,Illness Profiles,and the Implication of COVID-19 Before and After the Nationwide Omicron Outbreak During the Winter of 2022显示文摘China.In this study,we aimed to investigate the clinical characteristics and outcomes of patients with coronavirus disease 2019(COVID-19)in the Beijing region.Methods:In this retrospective study,we enrolled inpatients admitted for COVID-19 in the Fifth Medical Center of Chinese PLA General Hospital in Beijing between November 10,2022,and January 30,2023.Demographic and clinical features and treatment outcomeswere comprehensively analyzed.We used logistic regression and linear regression analyses to explore the risk factors associated with disease severity and time of nucleic acid conversion,respectively.Results:A total of 1010 hospitalized patients with COVID-19 were enrolled.The median age was 43.0 years(interquartile range,28.0–63.0),and patients aged<60 years and≥60 years comprised 71.2%and 28.8%of total included patients,respectively.The clinical classification of mild(74.6%,753/1010),moderate(21.0%,212/1010),severe(2.7%,27/1010),and unidentified(1.8%,18/1010)was separately recorded;1005 patients were discharged,and 5 patients died in the hospital.The outbreak of the emerging epidemic witnessed an evident increase in the proportion of moderate(42.9%vs.16.4%)and severe(10.3%vs.1.1%)cases after December 7,2022.Patients with a moderate/severe classification had higher levels of procalcitonin,IL-6,serum ferritin,C-reactive protein,lactic dehydrogenase,serum urea nitrogen,and D-dimer and lower counts of CD4+T,CD8+T,and B cells(all P<0.001).Multivariable regression analysis revealed that increased odds of disease severity were associated with the following factors:age≥60 years,IL-6>7 pg/mL,lactic dehydrogenase level>245 U/L,cough,and fever at admission.Age≥80 years and chronic lung diseasewere independent risk factors in the nonmild group in elderly patients.In addition,the duration for nucleic acid to turn negativewas approximately 5.0 d(interquartile range,3.0–7.0).Prolonged time of nucleic acid conversion was associated with age≥60 years,serum urea nitrogen level>8.2 mmol/L,neutrophil count>7×10^(9)/L,and the presence of a chronic lung disease or carcinoma.Finally,unvaccinated patients accounted for 37.3%of enrolled patients;children and the elder people accounted for approximately half of that.The univariable analysis found that booster doses reduced disease severity and shortened the time of nucleic acid conversion in elderly patients.Conclusions:The outbreak ofOmicron rapidly increased the number of patientswith COVID-19 in Beijing.In elderly patients,booster doses may reduce disease severity and shorten the time of nucleic acid conversion.Healthcare systems should be optimized before an emerging epidemic outbreak. | Yuming Guo Zhe Xu Wen-Xin Wang Cheng Zhen Jinhua Hu Jinsong Mu Chengcheng Ji Xin Yuan Ruonan Xu Lei Huang Lei Shi Fanping Meng Junliang Fu Shuangnan Zhou Siyu Wang Fengyi Li Bo Tu Dawei Zhang Huihuang Huang Yufeng Mao Wen Xu Chao Zhang Xiuying Mu Jun Zhao Bo Jin Haibin Su Yinying Lu Yongqian Cheng Dong Ji Shaoli You Jinghui Dong Changchun Liu Mengmeng Zhang Yuanyuan Li Tianjun Jiang Yonggang Li Fu-Sheng Wang | 2023 | Infectious Diseases & Immunity2023，3，4： | 0 |
| 19 | Photochemical production of carbonyl sulfide,carbon disulfide and dimethyl sulfide in a lake water显示文摘Photochemical production of carbonyl sulfide(COS),carbon disulfide(CS_2) and dimethyl sulfide(DMS) was intensively studied in the water from the Aohai Lake of Beijing city.The lake water was found to be highly supersaturated with COS,CS_2 and DMS,with their initial concentrations of 0.91 ± 0.073 nmol/L,0.55 ± 0.071 nmol/L and 0.37 ± 0.062 nmol/L,respectively.The evident photochemical production of COS and CS_2 in the lake water under irradiation of 365 nm and 302 nm indicated that photochemical production of them might be the reason for their supersaturation.The similar dependence of wavelength and oxygen for photochemical production of COS,CS_2 and DMS implied that they might be from the same precursors.The water cage effect was found to favor COS production but inhibit CS_2and DMS formation,indicating that COS photochemical production was mainly from direct degradation of the precursors and the formation of CS_2 and DMS needed intermediates via combination of carbon-centered radicals and sulfur-centered radicals.The above assumptions were further confirmed by simulation experiments with addition of carbonyls and amino acids(cysteine and methionine),and the photochemical formation mechanisms for COS,CS_2 and DMS in water were derived from the investigations. | Qianqian Du Yujing Mu Chenglong Zhang Junfeng Liu Yuanyuan Zhang Chengtang Liu | 2017 | Journal of Environmental Sciences2017，29，1： | 0 |
| 20 | Evaluation of offline sampling for atmospheric C3-C11 non-methane hydrocarbons显示文摘The concentration variation of C3-C11 non-methane hydrocarbons(NMHCs)collected in several types of commercial flexible bags and adsorption tubes was systematically inves-tigated using a gas chromatography-flame ionization detector(GC-FID)system.The per-centage loss of each NMHC in the polyvinyl fluoride(PVF)bags was less than 5%during a 7-hr storage period;significant NMHCs loss was detected in aluminum foil composite film and fluorinated ethylene propylene bags.The thermal desorption efficiency of NMHCs for adsorption tubes filled Carbopack B and Carboxen1000 sorbents was greater than 95%at 300℃,and the loss of NMHCs in the adsorption tubes during 20-days storage at 4℃was less than 8%.The thermal desorption efficiency for C11 NMHCs in the adsorption tube filled with Carbograph 1 and Carbosieve SⅢabsorbents was less than 40%at 300℃,and pyrolysis of the absorbents at 330℃interfered significantly with the measurements of some alkenes.The loss of alkenes was significant when NMHCs were sampled by cryo-enrichment at-90℃in the presence of O3 for the online NMHC measurements,and negligible for enrichment us-ing adsorption tubes at 25℃.Although O_(3)scrubbers have been widely used to eliminate the influence of O_(3)on NMHC measurements,the loss of NMHCs with carbon numbers greater than 8 was more than 10%.Therefore,PVF bags and adsorption tubes filled Carbopack B and Carboxen1000 sorbents were recommended for the sampling of atmospheric NMHCs. | Zhiguo Liu Chengtang Liu Zhouming He Yujing Mu Chenglong Zhang Yuanyuan Zhang Pengfei Liu Yuzheng Wang Junfeng Liu | 2022 | Journal of Environmental Sciences2022，34，3： | 0 |
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