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| 1 | Mechanism for the formation of the January 2013 heavy haze pollution episode over central and eastern China显示文摘In January 2013,a long-lasting episode of severe haze occurred in central and eastern China,and it attracted attention from all sectors of society.The process and evolution of haze pollution episodes were observed by the'Forming Mechanism and Control Strategies of Haze in China'group using an intensive aerosol and trace gases campaign that simultaneously obtained data at 11 ground-based observing sites in the CARE-China network.The characteristics and formation mechanism of haze pollution episodes were discussed.Five haze pollution episodes were identified in the Beijing-Tianjin-Hebei(Jing-Jin-Ji)area;the two most severe episodes occurred during 9–15 January and 25–31 January.During these two haze pollution episodes,the maximum hourly PM2.5mass concentrations in Beijing were 680 and 530μg m 3,respectively.The process and evolution of haze pollution episodes in other major cities in the Jing-Jin-Ji area,such as Shijiazhuang and Tianjin were almost the same as those observed in Beijing.The external cause of the severe haze episodes was the unusual atmospheric circulation,the depression of strong cold air activities and the very unfavorable dispersion due to geographical and meteorological conditions.However,the internal cause was the quick secondary transformation of primary gaseous pollutants to secondary aerosols,which contributed to the'explosive growth'and'sustained growth'of PM2.5.Particularly,the abnormally high amount of nitric oxide(NOx)in the haze episodes,produced by fossil fuel combustion and vehicle emissions,played a direct or indirect role in the quick secondary transformation of coal-burning sulphur dioxide(SO2)to sulphate aerosols.Furthermore,gaseous pollutants were transformed into secondary aerosols through heterogeneous reactions on the surface of fine particles,which can change the particle’s size and chemical composition.Consequently,the proportion of secondary inorganic ions,such as sulphate and nitrate,gradually increased,which enhances particle hygroscopicity and thereby accelerating formation of the haze pollution. | WANG YueSi YAO Li WANG LiLi LIU ZiRui JI DongSheng TANG GuiQian ZHANG JunKe SUN Yang HU Bo XIN JinYuan | 2014 | Science China Earth Sciences2014，57，1： | 189 |
| 2 | Contrasting trends of PM2.5 and surface-ozone concentrations in China from 2013 to 2017显示文摘Although much attention has been paid to investigating and controlling air pollution in China,the trends of air-pollutant concentrations on a national scale have remained unclear.Here,we quantitatively investigated the variation of air pollutants in China using long-term comprehensive data sets from 2013 to 2017,during which Chinese government made major efforts to reduce anthropogenic emission in polluted regions.Our results show a significant decreasing trend in the PM2.5 concentration in heavily polluted regions of eastern China,with an annual decrease of〜7%compared with measurements in 2013.The measured decreased concentrations of SO2>NO2 and CO(a proxy for anthropogenic volatile organic compounds)could explain a large fraction of the decreased PM2.5 concentrations in different regions.As a consequence;the heavily polluted days decreased significantly in corresponding regions.Concentrations of organic aerosol;nitrate;sulfate,ammonium and chloride measured in urban Beijing revealed a remarkable reduction from 2013 to 2017;connecting the decreases in aerosol precursors with corresponding chemical components closely.However;surface-ozone concentrations showed increasing trends in most urban stations from 2013 to 2017;which indicates stronger photochemical pollution.The boundary-layer height in capital c让ies of eastern China showed no significant trends over the Beijing-Tianjin-Hebei,Yangtze River Delta and Pearl River Delta regions from 2013 to 2017;which confirmed the reduction in anthropogenic emissions.Our results demonstrated that the Chinese government was successful in the reduction of particulate matter in urban areas from 2013 to 2017,although the ozone concentration has increased significantly;suggesting a more complex mechanism of improving Chinese air quality in the future. | Yonghong Wang Wenkang Gao Shuai Wang Tao Song Zhengyu Gong Dongsheng Ji Lili Wang Zirui Liu Guiqian Tang Yanfeng Huo Shili Tian Jiayun Li Mingge Li Yuan Yang Biwu Chu Tuukka Petaja Veli-Matti Kerminen Hong He Jiming Hao Markku Kulmala Yuesi Wang Yuanhang Zhang | 2020 | National Science Review2020，7，8： | 51 |
| 3 | Trends in particulate matter and its chemical compositions in China from 2013–2017显示文摘Accurate determination of the atmospheric particulate matter mass concentration and chemical composition is helpful in exploring the causes and sources of atmospheric enthalpy pollution and in evaluating the rationality of environmental air quality control strategies.Based on the sampling and chemical composition data of PM2.5 in different key regions of China in the CARE-China observation network,this research analyzes the environmental air quality data released by the China National Environmental Monitoring Centre during the studied period to determine the changes in the particulate matter mass concentration in key regions and the evolution of the corresponding chemical compositions during the implementation of the Action Plan for Prevention and Control of Air Pollution from 2013-2017.The results show the following.(1)The particulate matter mass concentration in China showed a significant downward trend;however,the PM2.5 annual mass concentration in 64%of cities exceeds the New Chinese Ambient Air Quality Standard(CAAQS)GradeⅡ(GB3095-2012).The region to the east of the Taihang Mountains,the Fenhe and Weihe River Plain and the Urumqi-Changji regions in Xinjiang,all have PM2.5 concentration loading that is still high,and heavy haze pollution occurred frequently in the autumn and winter.(2)During the heavy pollution in the autumn and winter,the concentrations of sulfate and organic components decreased significantly.The mean SO42-concentration in PM2.5 decreased by 76%,12%,81%and 38%in Beijing-Tianjin-Hebei(BTH),the Pearl River Delta(PRD),the Sichuan-Chongqing region(SC)and the Fenhe and Weihe River Plain,respectively.The mean organic matter(OM)concentration decreased by 70%,44%,48%and 31%,respectively,and the mean concentration of NH4+decreased by 68%,1.6%,38%and 25%,respectively.The mean elemental carbon(EC)concentration decreased by 84%and 20%in BTH and SC,respectively,and it increased by 61%and 11%in the PRD and Fenhe and Weihe River Plain,respectively.The mean concentration of mineral and unresolved chemical components(MI)dropped by 70%,24%and 13%in BTH,the PRD and the Fenhe and Weihe River Plain,respectively.The change in the PM2.5 chemical composition is consistent with the decrease of the PM2.5mass concentration.(3)In 2015,the mean OM concentration contributions to fine particles and coarse particles were 13-46%and 46-57%,respectively,and the mean MI concentration contributions to fine particles and coarse and particles were 31-60%and 39-73%,respectively;these values are lower than the 2013 values from the key regions,which is the most important factor behind the decrease of the particulate matter mass concentration.From 2013 to 2015,among the chemical components of different particle size fractions,the peak value of the coarse particle size fraction decreased significantly,and the fine particle size fractions of SO42-,NO3-,and NH4+decreased with the decrease of the particulate matter mass concentration in different particle size fractions.The fine-particle size peaks of SO42-,NO3-and NH4+shifted from 0.65-1.1μm to the finer size range of0.43-0.65μm during the same time frame. | Yuesi WANG Wenjie LI Wenkang GAO Zirui LIU Shili TIAN Rongrong SHEN Dongsheng JI Shuai WANG Lili WANG Guiqian TANG Tao SONG Mengtian CHENG Gehui WANG Zhengyu GONG Jiming HAO Yuanhang ZHANG | 2019 | Science China Earth Sciences2019，62，12： | 23 |
| 4 | In situ measurement of PM_1 organic aerosol in Beijing winter using a high-resolution aerosol mass spectrometer显示文摘Organic aerosol (OA) is a crucial component of atmospheric fine particles. To achieve a better understanding of the chemical characteristics and sources of OA in Beijing, the size-resolved chemical composition of submicron aerosols were measured in-situ using a High-Resolution Time-of-Flight Aerosol Mass Spectrometer in the winter of 2010, with a high time resolution of 5 min. During this study, the mean OA mass concentration was 20.9±25.3 μg/m3, varying between 1.9 and 284.6 μg/m3. Elemental analysis showed that the average H/C, O/C and N/C (molar ratio) were 1.70, 0.17, and 0.005, respectively, corresponding to an OM/OC ratio (mass ratio of organic matter to organic carbon) of 1.37. The average mass-based size distributions of OA present a promi- nent accumulation mode peaking at approximately 450 nm. The prominent presence of ultrafine particles (Dva < 100 nm) was mainly from the fresh emissions of combustion sources. A Positive Matrix Factorisation (PMF) analysis of the organic mass spectral dataset differentiated the OA into three components, including hydrocarbon-like (HOA), cooking-related (COA), and oxygenated (OOA) organic aerosols, which, on average, accounted for 26.9%, 49.7% and 23.4%, respectively, of the total organic mass. The HOA and COA likely corresponded to primary organic aerosol (POA) associated with combustion-related and cooking emissions, respectively, and the OOA components corresponded to aged secondary organic aerosol (SOA). | LIU Quan SUN Yang HU Bo LIU ZiRui AKIO Shimono WANG YueSi | 2012 | Chinese Science Bulletin2012，57，7： | 14 |
| 5 | Cryptotanshinone suppresses key onco-proliferative and drugresistant pathways of chronic myeloid leukemia by targeting STAT5 and STAT3 phosphorylation显示文摘C-Myc and signal transducer and activator of transcription(STAT) family proteins have been proposed to be important downstream genes of BCR-ABL, which characterizes most cases of chronic myeloid leukemia(CML). Here, we report a c-Myc pathway-targeted screening of seven natural anticancer compounds, in which we identified cryptotanshinone as a highly promising agent for CML therapy. Cryptotanshinone depletes c-Myc in CML by repressing the phosphorylation of STAT5.Decreased viability of K562 cells correlated with p-STAT5 suppression. Unexpectedly, imatinib activates rather than inhibits the phosphorylation of STAT3 in K562 cells. We demonstrated that cryptotanshinone, as a dual inhibitor of p-STAT5 and p-STAT3,can effectively block IL-6-mediated STAT3 activation and reverse BCR-ABL kinase-independent drug resistance. Moreover, we showed that the epigenetic rebalance between decreased BCR-ABL/STAT5/c-Myc and enhanced STAT3/multi-drug resistance(MDR) pathways is characteristic of the cancer stem cell-like property of K562/ADR. Simultaneously suppressing these two pathways using cryptotanshinone proves to be critical for the malignant network redress and MDR reversal of K562/ADR. These studies reveal the dual functions of cryptotanshinone that suppress key oncogenic proliferation and drug-resistant pathways in CML cells by targeting p-STAT5 and p-STAT3, providing a new strategy for CML therapy that takes advantage of natural products. | Bowen Dong Zirui Liang Zhirong Chen Bin Li Lingling Zheng Jianhua Yang Hui Zhou Lianghu Qu | 2018 | Science China(Life Sciences)2018，61，9： | 10 |
| 6 | Dietary seaweed-derived polysaccharides improve growth performance of weaned pigs through maintaining intestinal barrier function and modulating gut microbial populations显示文摘Background:Seaweed-derived polysaccharides(SDP)represent an attractive source of prebiotic nutraceuticals for the food and animal husbandry industry.However,the mechanism by which SDP from Enteromorpha mediates pig growth are not fully understood.This study aimed to investigate how SDP supplementation influences the growth performance and intestinal health in weaned pigs.Results:In Exp.1,240 weaned pigs were randomly assigned to four dietary treatments and fed with a basal diet or a basal diet containing 200,400 or 800 mg/kg SDP,respectively,in a 21-day trial.Pigs on the 400 or 800 mg/kg SDP-supplemented group had greater ADG and lower F/G ratio than those on the control group(P<0.05).In Exp.2,20 male weaned pigs were randomly assigned to two treatments and fed with a basal diet(CON group)or a basal diet supplemented with 400 mg/kg SDP(the optimum does from Exp.1),in a 21-day trial.Pigs fed the SDP diet had greater ADG,the concentrations of serum IL-6 and TNF-αand the activities of glutathione peroxidase,superoxide dismutase and catalase(P<0.05),and lower F/G,diarrhea rate,as well as serum D-lactate concentrations and diamine oxidase activity(P<0.05).Moreover,dietary SDP supplementation enhanced secretory immunoglobulin A content,villus height and villous height:crypt depth ratio in small intestine,as well as the lactase and maltase activities in jejunum mucosa(P<0.05).SDP supplementation elevated the mRNA levels of inflammatory responserelated genes(IL-6,TNF-α,TLR4,TLR6 and MyD88),and the mRNA and protein levels of ZO-1,claudin-1 and occludin in jejunum mucosa(P<0.05).Importantly,SDP not only increased the Lactobacillus population but also reduced the Escherichia coli population in cecum(P<0.05).Furthermore,SDP increased acetic acid and butyric acid concentrations in cecum(P<0.05).Conclusions:These results not only suggest a beneficial effect of SDP on growth performance and intestinal barrier functions,but also offer potential mechanisms behind SDP-facilitated intestinal health in weaned pigs. | Tiande Zou Jin Yang Xiaobo Guo Qin He Zirui Wang Jinming You | 2021 | Journal of Animal Science and Biotechnology2021，12，3： | 10 |
| 7 | Hierarchical composite of biomass derived magnetic carbon framework and phytic acid doped polyanilne with prominent electromagnetic wave absorption capacity显示文摘To solve the electromagnetic pollution,herein,a CoFe_(2)O_(4)/C/PANI composite was developed by a green route,which was constructed with spinel of metal oxide,graphitized carbon and conductive polymer composites.Benefiting from the designable interfaces and increased dipoles,the microwave dielectric response capability can be boosted significantly and resulted in the enhanced microwave absorbing performance.As revealed by the reflection loss curve,the minimum reflection loss(RLmin) reached-51.81 dB at 12.4 GHz under a matched thickness of 2.57 mm.At 2.5 mm,the effective absorbing band covered 8.88 GHz,suggesting the desirable wideband feature.In our case,the method of utilization of a novel green way to fabricate multiple-component EM absorber can be a promising candidate for high-performance EM absorber. | Tianqi Hou Zirui Jia Ailing Feng Zehua Zhou Xuehua Liu Hualiang Lv Guanglei Wu | 2021 | Journal of Materials Science & Technology2021，，9： | 8 |
| 8 | Construction of 1D Heterostructure NiCo@C/ZnO Nanorod with Enhanced Microwave Absorption显示文摘Layered double hydroxides(LDHs)have a special structure and atom composition,which are expected to be an excellent electromagnetic wave(EMW)absorber.However,it is still a problem that obtaining excellent EMWabsorbing materials from LDHs.Herein,we designed heterostructure NiCo-LDHs@ZnO nanorod and then subsequent heat treating to derive NiCo@C/ZnO composites.Finally,with the synergy of excellent dielectric loss and magnetic loss,an outstanding absorption performance could be achieved with the reflection loss of−60.97 dB at the matching thickness of 2.3 mm,and the widest absorption bandwidth of 6.08 GHz was realized at 2.0 mm.Moreover,this research work provides a reference for the development and utilization of LDHs materials in the field of microwave absorption materials and can also provide ideas for the design of layered structural absorbers. | Jianwei Wang Zirui Jia Xuehua Liu Jinlei Dou Binghui Xu Bingbing Wang Guanglei Wu | 2021 | Nano-Micro Letters2021，13，11： | 7 |
| 9 | Chemical characteristics and source apportionment of PM_(2.5) in a petrochemical city: Implications for primary and secondary carbonaceous component显示文摘To study the pollution features and underlying mechanism of PM_(2.5) in Luoyang, a typical developing urban site in the central plain of China, 303 PM_(2.5) samples were collected from April 16 to December 29, 2015 to analyze the elements, water soluble inorganic ions, organic carbon and elemental carbon. The annual mean concentration of PM_(2.5) was 142.3 μg/m^(3), and 75% of the daily PM_(2.5) concentrations exceeded the 75 μg/m^(3). The secondary inorganic ions, organic matter and mineral dust were the most abundant species, accounting for 39.6%, 19.2% and 9.3% of the total mass concentration, respectively. But the major chemical components showed clear seasonal dependence. SO_(4)^(2-) was most abundant specie in spring and summer, which related to intensive photochemical reaction under high O_3 concentration. In contrast, the secondary organic carbon and ammonium while primary organic carbon and ammonium significantly contributed to haze formation in autumn and winter, respectively. This indicated that the collaboration effect of secondary inorganic aerosols and carbonaceous matters result in heavy haze in autumn and winter. Six main sources were identified by positive matrix factorization model: industrial emission, combustion sources, traffic emission, mineral dust, oil combustion and secondary sulfate, with the annual contribution of 24%, 20%, 24%, 4%, 5% and 23%, respectively. The potential source contribution function analysis pointed that the contribution of the local and short-range regional transportation had significant impact. This result highlighted that local primary carbonaceous and precursor of secondary carbonaceous mitigation would be key to reduce PM_(2.5) and O_3 during heavy haze episodes in winter and autumn. | Guangxuan Yan Puzhen Zhang Jie Yang Jingwen Zhang Guifen Zhu Zhiguo Cao Jing Fan Zirui Liu Yuesi Wang | 2021 | Journal of Environmental Sciences2021，33，5： | 6 |
| 10 | Magnetic manganese-based composites with multiple loss mechanisms towards broadband absorption显示文摘The weak dielectric properties and the lack of magnetic loss of manganese-based absorbers are obstructed as the new generation of electromagnetic wave absorption(EMA)materials applying in microelectronic devices.Herein,the sulfuration and subsequent compounding strategies have been employed to enhance the EMA performance of multi-shell nanosphere-shaped Mn_(2)O_(3)materials.With the narrow bandgap,the as-obtained MnS possesses reinforced electrical conductivity,which is conducive to conductivity loss.More importantly,the presence of potential difference between different phases will form space charge region at the heterogeneous interface,thus favoring interfacial polarization.Additionally,the improvement of magnetic loss is attributed to the presence of Co_(3)O_(4)nanoparticles.Consequently,the composites present enhanced EMA performance than original Mn_(2)O_(3).Specifically,the minimum reflection loss of as-prepared composites is−51.4 dB at the thickness of 1.8 mm and the broad effective absorption bandwidth reaches 6.2 GHz at 1.9 mm.The low matching thickness and high absorption efficiency in this work can provide a convincing reference when designing distinguished manganese-based absorbers. | Yue Liu Zirui Jia Qianqian Zhan Yuhao Dong Qimeng Xu Guanglei Wu | 2022 | Nano Research2022，15，6： | 6 |
| 11 | Construction of Self-Assembly Based Tunable Absorber:Lightweight,Hydrophobic and Self-Cleaning Properties显示文摘Although multifunctional aerogels are expected to be used in applications such as portable electronic devices,it is still a great challenge to confer multifunctionality to aerogels while maintaining their inherent microstructure.Herein,a simple method is proposed to prepare multifunctional NiCo/C aerogels with excellent electromagnetic wave absorption properties,superhydrophobicity,and self-cleaning by water-induced NiCo-MOF self-assembly.Specifically,the impedance matching of the three-dimensional(3D)structure and the interfacial polarization provided by CoNi/C as well as the defect-induced dipole polarization are the primary contributors to the broadband absorption.As a result,the prepared NiCo/C aerogels have a broadband width of 6.22 GHz at 1.9 mm.Due to the presence of hydrophobic functional groups,CoNi/C aerogels improve the stability in humid environments and obtain hydrophobicity with large contact angles>140°.This multifunctional aerogel has promising applications in electromagnetic wave absorption,resistance to water or humid environments. | Zehua Zhou Qianqian Zhu Yue Liu Yan Zhang Zirui Jia Guanglei Wu | 2023 | Nano-Micro Letters2023，15，9： | 5 |
| 12 | Macroscopic electromagnetic synergy network-enhanced N-doped Ni/C gigahertz microwave absorber with regulable microtopography显示文摘To achieve excellent electromagnetic wave(EMW)absorption properties,the microstructure design of the absorber is critical.In this work,six kinds of N-Ni/C nanostructures with different morphologies were prepared by one-step hydrothermal method and high temperature carbonization by adjusting the types of nickel salts and reaction solvents.The EMW absorption performance of six different morphologies of N-Ni/C nanostructures was compared and analyzed.Among them,it is found that the nanoflowerlike N-Ni/C composite has excellent dielectric loss and magnetic loss synergistic effect due to its polycrystalline structure,and can obtain excellent EMW absorption performance.The minimum reflection loss value at a thickness of 1.9 mm is-59.56 dB at 16.88 GHz,and the effective absorption bandwidth value reaches 6.0 GHz at a thickness of 2.2 mm.Our research shows that different morphologies and multiple lattice structures of nanostructures with the same composition have a significant influence on EMW absorption performance,which provides new research ideas for developing high-performance EMW absorbing materials. | Yuelei Pan Qianqian Zhu Jiahui Zhu Yuhang Cheng Bowen Yu Zirui Jia Guanglei Wu | 2023 | Nano Research2023，16，7： | 5 |
| 13 | Tunable Co/ZnO/C@MWCNTs based on carbon nanotube-coated MOF with excellent microwave absorption properties显示文摘The development of global information technology makes human life intelligent,and the large-scale use of various electronic devices increases the electromagnetic radiation in the surrounding environment.This has created a requirement for the development of high-performance electromagnetic wave absorbers to eliminate electromagnetic pollution.However,the preparation of electromagnetic wave absorbers with excellent electromagnetic loss capability remains a great challenge.Here,we present a method to prepare Co/ZnO/C@MWCNTs(CZC@M)composites by pyrolysis of ZnCo-MOF@MWCNTs(MOF@M).Specifically,MWCNTs are uniformly distributed on the CZC surface to form multiple heterogeneous interfaces,which will lead to an increase in polarizability.In addition,changing the amounts of MWCNTs in the composite can modulate its dielectric constant and impedance matching properties.Impressively,at only 10%sample content,the minimum reflection loss of-41.75 d B and the maximum effective absorption bandwidth of 4.72 GHz are obtained at thicknesses of 2.4 mm and 2.2 mm,respectively.Overall,the results reported in this work provide a new design strategy for the synthesis of high-performance electromagnetic wave absorbers with potential applications in the elimination of electromagnetic pollution. | Zirui Jia Mingyue Kong Bowen Yu Yingzhuo Ma Jiaying Pan Guanglei Wu | 2022 | Journal of Materials Science & Technology2022，，32： | 5 |
| 14 | Controllable synthesis of Ni/NiO@porous carbon hybrid composites towards remarkable electromagnetic wave absorption and wide absorption bandwidth显示文摘The reasonable design of the composition of the composite materials is of great significance to optimized the electromagnetic(EM)wave absorption performance.Herein,the Ni/NiO@C hybrid composites with tunable Ni proportion were successfully synthesized through a two-step process.With the assistance of X-ray diffraction with refinement treatment,the specific proportion of Ni of as-obtained hybrid composites could be obtained.Employing controlling calcination time to adjust the Ni content of Ni/NiO@C hybrid composites,it has been found that the composite carbonized at 500℃exhibited remarkable EM wave absorption with the minimum reflection loss(RLmin)of-49.1 dB at 4.9 mm and the widest effective absorption bandwidth(EABmax)of 4.56 GHz at 2.1 mm.Moreover,by adjusting the Ni source,the optimal EM wave absorption performance could be achieved.Results illustrated that the N3PC with the Ni proportion of 13.17%showed the RLm inas low as-51.1 dB at 2.4 mm and the EABmax was 5.12 GHz at 2.7 mm.It is worth noting that this work demonstrates the relevance of the composition and EM wave absorption performance of hybrid composites,which offers a feasible reference for the absorption mechanism of absorber. | Xinfeng Zhou Zirui Jia Xingxue Zhang Bingbing Wang Wei Wu Xuehua Liu Binghui Xu Guanglei Wu | 2021 | Journal of Materials Science & Technology2021，，28： | 5 |
| 15 | Characterization of submicron particles during autumn in Beijing,China显示文摘In this study, we performed a highly time-resolved chemical characterization of nonrefractory submicron particles(NR-PM_1) in Beijing by using an Aerodyne high-resolution time-of-flight aerosol mass spectrometer(HR-ToF-AMS). The results showed the average NR-PM_1 mass concentration to be 56.4 ± 58.0 μg/m^3, with a peak at 307.4 μg/m^3. Due to the high frequency of biomass burning in autumn, submicron particles significantly increased in organic content, which accounted for 51% of NR-PM_1 on average. Secondary inorganic aerosols(sulfate + nitrate + ammonium) accounted for 46% of NR-PM_1, of which sulfate,nitrate, and ammonium contributed 15%, 20%, and 11%, respectively. To determine the intrinsic relationships between the organic and inorganic species, we used the positive matrix factorization(PMF) model to merge the high-resolution mass spectra of the organic species and NO+and NO_2^+ions. The PMF analysis separated the mixed organic and nitrate(NO+and NO_2^+) spectra into four organic factors, including hydrocarbon-like organic aerosol(HOA), oxygenated organic aerosol(OOA), cooking organic aerosol(COA), and biomass burning organic aerosol(BBOA), as well as one nitrate inorganic aerosol(NIA) factor. COA(33%) and OOA(30%) contributed the most to the total organic aerosol(OA) mass, followed by BBOA(20%) and HOA(17%). We successfully quantified the mass concentrations of the organic and inorganic nitrates by the NO+and NO2+ions signal in the organic and NIA factors. The organic nitrate mass varied from 0.01-6.8 μg/m^3, with an average of 1.0 ±1.1 μg/m^3, and organic nitrate components accounted for 10% of the total nitrate mass in this observation. | Peng Xu Junke Zhang Dongsheng Ji Zirui Liu Guiqian Tang Changsheng Jiang Yuesi Wang | 2018 | Journal of Environmental Sciences2018，30，1： | 5 |
| 16 | Three-dimensional distinct element modeling of fault reactivation and induced seismicity due to hydraulic fracturing injection and backflow显示文摘This paper presents a three-dimensional fully hydro-mechanical coupled distinct element study on fault reactivation and induced seismicity due to hydraulic fracturing injection and subsequent backflow process,based on the geological data in Horn River Basin,Northeast British Columbia,Canada.The modeling results indicate that the maximum magnitude of seismic events appears at the fracturing stage.The increment of fluid volume in the fault determines the cumulative moment and maximum fault slippage,both of which are essentially proportional to the fluid volume.After backflow starts,the fluid near the joint intersection keeps flowing into the critically stressed fault,rather than backflows to the wellbore.Although fault slippage is affected by the changes of both pore pressure and ambient rock stress,their contributions are different at fracturing and backflow stages.At fracturing stage,pore pressure change shows a dominant effect on induced fault slippage.While at backflow stage,because the fault plane is under a critical stress state,any minor disturbance would trigger a fault slippage.The energy analysis indicates that aseismic deformation takes up a majority of the total deformation energy during hydraulic fracturing.A common regularity is found in both fracturing-and backflow-induced seismicity that the cumulative moment and maximum fault slippage are nearly proportional to the injected fluid volume.This study shows some novel insights into interpreting fracturing-and backflowinduced seismicity,and provides useful information for controlling and mitigating seismic hazards due to hydraulic fracturing. | Zirui Yin Hongwei Huang Fengshou Zhang Lianyang Zhang Shawn Maxwell | 2020 | Journal of Rock Mechanics and Geotechnical Engineering2020，12，4： | 4 |
| 17 | Improving simulations of sulfate aerosols during winter haze over Northern China: the impacts of heterogeneous oxidation by NO2显示文摘 | Meng Gao Gregory R. Carmichael Yuesi Wang Dongsheng Ji Zirui Liu Zifa Wang | 2016 | Frontiers of Environmental Science & Engineering2016，10，5： | 4 |
| 18 | Electrospun Fe_(0.64)Ni_(0.36)/MXene/CNFs nanofibrous membranes with multicomponent heterostructures as flexible electromagnetic wave absorbers显示文摘Two-dimensional metal carbide or nitride materials(MXenes)are widely used in electromagnetic wave absorption because of their unique structure.Herein,a novel composite preparation strategy has been proposed to design dendritic nanofibers based on the electrostatic spinning methods.The multifunctional MXene nanosheets are used as the dendritic matrix,and magnetic nanoparticles are embedded in the nanosheets as magnetic loss units.Multidimensional nanocomposites have interlaced carbon fiber networks,large-scale magnetically coupled networks,and a lot of multi-heterojunction interface structures,which endow the composites with extraordinary conduction loss,magnetic loss,and polarization loss capabilities,respectively.The impedance matching and loss mechanisms of the composites are improved by optimizing the synergistic relationship between the components and building a suitable structure.The optimum reflection loss(RL)of−54.1 dB is achieved at 2.7 mm and a wide effective absorption bandwidth(EAB,RL below−10 dB)of 7.76 GHz is obtained at a small thickness of 2.1 mm for the nanocomposites.The distinctive microstructures of the nanofibrous membranes give rise to their flexibility,waterproof,and electromagnetic wave absorption performance and endow the nanofibrous membranes potential to be utilized as lightweight,efficient electromagnetic wave protective fabric in harsh environment. | Shuo Zhang Zirui Jia Yan Zhang Guanglei Wu | 2023 | Nano Research2023，16，2： | 4 |
| 19 | Metal-organic framework-derived CoSn/NC nanocubes as absorbers for electromagnetic wave attenuation显示文摘Metal-organic framework-derived composites have been widely used in electromagnetic wave(EMW)absorption,but the traditional synthetic strategy greatly limits the structure and species of MOFs.This research provided a solvent-free method to synthesize Co-MOF and its derivatives.Using CoSnO_(3)as the precursor,the preparation of Co-MOF is achieved by bridging the cobalt(II)ion of CoSnO_(3)and the 2-methylimidazole skeleton.The CoSn/N-doped carbon(CoSn/NC)composites derived from CoSnO_(3)-MOF(Co-MOF with CoSnO_(3)as Co source)retain the original morphology of CoSnO_(3).Besides,the polarization effect produced by the N-doped carbon layers also benefits the excellent EMW absorption performance of the CoSn/NC composites.It is reflected in the minimum reflection loss(RL)of-48.2 dB at 2.2 mm and the effective bandwidth(EBA)of 5.84 GHz.This work provides a new channel to the construction of Co-MOFs,which could be extended to other Co-based oxides and vastly expand the species of MOFs based on metallic Co. | Chenxi Wang Zirui Jia Shuangqiao He Jixi Zhou Shuo Zhang Mengli Tian Bingbing Wang Guanglei Wu | 2022 | Journal of Materials Science & Technology2022，，13： | 4 |
| 20 | Improved Stiffness Modeling for An Exechon‑Like Parallel Kinematic Machine(PKM)and Its Application显示文摘Hole drilling or contour milling for the large and complex workpieces such as automobile panels and aircraft fuselages makes a high combined demand on machining accuracy,stiffness and workspace of machining equipment.Therefore,a 5-DOF(degrees of freedom)parallel kinematic machine(PKM)with redundant constraints is proposed.Based on the kinematics analysis of the parallel mechanism using intermediate variables,the kinematics problems of the PKM are solved through equivalent kinematics model.The structural stiffness matrix method is adopted to model the stiffness of the parallel mechanism of the PKM,where the stiffness of each joint and branch component is obtained by stiffness formula and finite element analysis.And the stiffness model of the parallel mechanism is improved by correction coefficient matrix,each element of which is constructed as a polynomial function of three independent end variables of the parallel mechanism.The terminal stiffness matrices obtained by simulation result are used to determine the coefficients of polynomial function by least square fitting to describe the correction coefficient over the workspace of the parallel mechanism quantitatively.The experiment results prove that the modification method can greatly improve the stiffness model of the parallel mechanism.To enhance the machining accuracy of the PKM,the proposed kinematics model and the improved stiffness model are utilized to optimize the working stiffness of parallel machine by searching the best relative position of parallel machine and workpiece.A plate workpiece taken as example is examined in the case study section,which demonstrates the effectiveness of optimization method. | Nanyan Shen Liang Geng Jing Li Fei Ye Zhuang Yu Zirui Wang | 2020 | Chinese Journal of Mechanical Engineering2020，33，3： | 4 |
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