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98篇 您的检索式:作者名="Junhui Chen"
    题名 作者 年代 出处 被引量
1Human colorectal cancer-specific CCAT1-L IncRNA regulates long-range chromatin interactions at the MYC locus显示文摘人的 8q24 基因沙漠包含多重 enhancers 形式织物特定的远程的染色质与 MYC oncogene 循环,但是染色质在 MYC 地点循环怎么被调整,仍然保持糟糕理解。这里,我们表明那长 noncoding RNA (lncRNA ) , CCAT1-L,从一个地点在人的 colorectal 癌症明确地被抄录 MYC 在上游的 515 kb。这 lncRNA 在 MYC transcriptional 规定起一个作用并且支持远程的染色质循环。重要地, CCAT1-L 地点位于强壮的超级提高以内并且离 MYC 空间地靠近。CCAT1-L 击倒在 MYC 倡导者和它的 enhancers 之间的减少的远程的相互作用。另外, CCAT1-L 与 CTCF 交往并且在这些环区域调制染色质符合构造。这些结果揭示一个重要角色一以前在在 MYC 地点的基因规定的 unannotated lncRNA。Jian-Feng Xiang Qing-Fei Yin Tian Chen Yang Zhang Xiao-Ou Zhang Zheng Wu Shaofeng Zhang Hai-Bin Wang Junhui Ge Xutiua Lu Li Yang Ling-Ling Chen 2014Cell Research2014,24,5:67
2The Inhibitory Effect of Oridonin on the Growth of Fifteen Human Cancer Cell Lines显示文摘OBJECTIVE To study the inhibitory effect of oridonin on the growth of cancer cells. METHODS Fifteen human cancer cell lines were subjected to various concentrations of oridonin in culture medium. The inhibitory rate of cell growth was measured by the MTT assay, and compared with a negative con- trol and 5-Fu-positive control. RESULTS The 50% inhibiting concentration (IC50) and maximal inhibition (Imax) of oridonin shown by studying the growth of the cancer cell lines were as follows: leukemias (HL60 cells: 3.9 μg/ml and 73.8%, K562 cells: 4.3 μg/ml and 76.2%); esophageal cancers(SHEEC cells: 15.4 μg/ml and 99.2%, Eca109 cells: 15.1 μg/ml and 84.6%, TE1 cells: 4.0 μg/ml and 70.2%); gastric cancers (BGC823 cells: 7.6 μg/ml and 98.7%, SGC7901 cells: 12.3 μg/ml and 85.7%); colon cancers (HT29 cells: 13.6 μg/ml and 97.2%, HCT cells: 14.5 μg/ml and 96.5%); liver cancers (Bel7402 cells: 15.2 μg/ml and 89.2%, HepG2 cells: 7.1 μg/ml and 88.3%); pancreatic cancer (PC3 cells: 11.3 μg/ml and 68.4%); lung cancer (A549 cells: 18.6 μg/ml and 98.0% ); breast cancer (MCF7 cells: 18.4 μg/ml and 84.7%); uterine cervix cancer (Hela cells: 13.7 μg/ml and 98.5%). CONCLUSION Oridonin had a relatively wide anti-tumor spectrum, and a relatively strong inhibitory effect on the growth of the 15 human cancer cells. Inhibitory effects were concentration dependent.Junhui Chen Shaobin Wang Dongyang Chen Guisheng Chang Qingfeng Xin Shoujun Yuan Zhongying Shen 2007Chinese Journal of Clinical Oncology2007,4,1:32
3An efficient sparse channel estimator combining time-domain LS and iterative shrinkage for OFDM systems with IQ-imbalances显示文摘A time-domain(TD) least square(LS) channel estimator is first proposed to estimate channel parameters of OFDM system with IQ imbalances at both transmitter and receiver.Then,an iterative shrinkage(IS) algorithm from compressed sensing is adopted to further improve the estimation performance by using the TD-LS solution as the initial value of IS in the case of sparse channel.Simulation shows that our algorithm combining TD-LS and IS performs better on bit error rate than the frequency-domain LS and matching pursuit in sparse Hilly Terrain channel when the same LS equalizer is adopted.SHU Feng ZHAO JunHui YOU XiaoHu WANG Mao CHEN Qian STEVAN Berber 2012Science China(Information Sciences)2012,55,11:10
4Hollow spherical rare-earth-doped yttrium oxysulfate: A novel structure for upconversion显示文摘锻烧跟随的一条灵巧的 帮助biomolecule 的热水的线路为空范围与另外的稀土元素的离子做了的单斜晶的钇 oxysulfate 的准备被采用了( Yb <啜class=“ a-plus-plus ”>3+和 Eu <啜class=“ a-plus-plus ”>3+或嗯<啜class=“ a-plus-plus ”>3+)。空范围的形成可以包含 Ostwald 成熟。产生混合材料被用于 upconversion 应用。主人水晶结构允许容易没有显著地改变主人格子,二个不同稀土元素的金属离子共同做。光性质被稀土元素的金属离子由于精力转移和水晶的对称回答的掺杂物的比率和集中影响。光中心的类型和样品的 crystallinity 也被显示在同样准备的产品的光性质上有重要影响。Gen Chen Fashen Chen Xiaohe Liu Wei Ma Hongmei Luo Junhui Li Renzhi Ma Guanzhou Qiu 2014Nano Research2014,7,8:6
5Enhancement of precursor amino acid supplies for improving bacitracin production by activation of branched chain amino acid transporter BrnQ and deletion of its regulator gene lrp in Bacillus licheniformis显示文摘Bacitracin,a new type of cyclic peptide antibiotic,is widely used as the feed additive in feed industry.Branched chain amino acids(BCAAs)are the key precursors for bacitracin synthesis.In this research,soybean meal was served as the raw material to supply precursor amino acids for bacitracin synthesis,and enhanced production of bacitracin was attempted by engineering BCAA transporter BrnQ and its regulator Lrp in the bacitracin industrial production strain Bacillus licheniformis DW2.Firstly,our results confirmed that Lrp negatively affected bacitracin synthesis in DW2,and deletion of lrp improved intracellular BCAA accumulations,as well as the expression level of BCAA transporter BrnQ,which further led to a 14.71%increase of bacitracin yield,compared with that of DW2.On the contrary,overexpression of Lrp decreased bacitracin yield by 12.28%.Secondly,it was suggested that BrnQ acted as a BCAA importer in DW2,and overexpression of BrnQ enhanced the intracellular BCAA accumulations and 10.43%of bacitracin yield.While,the bacitracin yield decreased by 18.27%in the brnQ deletion strain DW2△brnQ.Finally,BrnQ was further overexpressed in lrp deletion strain DW2△lrp,and bacitracin yield produced by the final strain DW2△lrp::BrnQ was 965.34 U/mL,increased by 22.42%compared with that of DW2(788.48 U/mL).Collectively,this research confirmed that Lrp affected bacitracin synthesis via regulating the expression of BCAA transporter BrnQ and BCAA distributions,and provided a promising strain for industrial production of bacitracin.Jiang Zhu Dongbo Cai Haixia Xu Ziwei Liu Bowen Zhang Fei Wu Junhui Li Shouwen Chen 2018Synthetic and Systems Biotechnology2018,3,4:6
6Warm temperature compromises JA-regulated basal resistance to enhance Magnaporthe oryzae infection in rice显示文摘Changes in global temperatures profoundly affect the occurrence of plant diseases.It is well known that rice blast can easily become epidemic in relatively warm weather.However,the molecular mechanism remains unclear.In this study,we show that enhanced blast development at a warm temperature(22C)compared with the normal growth temperature(28C)is rice plant-determined.Comparative transcriptome analysis revealed that jasmonic acid(JA)biosynthesis and signaling genes in rice could be effectively induced by Magnaporthe oryzae at 28C but not at 22C.Phenotypic analyses of the osaoc1 and osmyc2 mutants,OsCOI1 RNAi lines,and OsMYC2-OE plants further demonstrated that compromised M.oryzaeinduced JA biosynthesis and signaling lead to enhanced blast susceptibility at the warm temperature.Consistent with these results,we found that exogenous application of methyl jasmonate served as an effective strategy for improving blast resistance under the warm environmental conditions.Furthermore,decreased activation of JA signaling resulted in the downregulated expression of some key basal resistance genes at 22C when compared with 28C.Among these affected genes,OsCEBiP(chitin elicitorbinding protein precursor)was found to be directly regulated by OsMYB22 and its interacting protein OsMYC2,a key component of JA signaling,and this contributed to temperature-modulated blast resistance.Taken together,these results suggest that warm temperature compromises basal resistance in rice and enhances M.oryzae infection by reducing JA biosynthesis and signaling,providing potential new strategies for managing rice blast disease under warm climate conditions.Jiehua Qiu Junhui Xie Ya Chen Zhenan Shen Huanbin Shi Naweed I.Naqvi Qian Qian Yan Liang Yanjun Kou 2022Molecular Plant2022,15,4:5
7Nb2C MXene-Functionalized Scaffolds Enables Osteosarcoma Phototherapy and Angiogenesis/Osteogenesis of Bone Defects显示文摘Early surgical resection and chemotherapy of bone cancer are commonly used in the treatment of bone tumor,but it is still highly challenging to prevent recurrence and fill the bone defect caused by the resection site.In this work,we report a rational integration of photonic-responsive two-dimensional(2D)ultrathin niobium carbide(Nb2C)MXene nanosheets(NSs)into the 3D-printed bone-mimetic scaffolds(NBGS)for osteosarcoma treatment.The integrated 2D Nb2C-MXene NSs feature specific photonic response in the second near-infrared(NIR-II)biowindow with high tissue-penetrating depth,making it highly efficient in killing bone cancer cells.Importantly,Nb-based species released by the biodegradation of Nb2C MXene can obviously promote the neogenesis and migration of blood vessels in the defect site,which can transport more oxygen,vitamins and energy around the bone defect for the reparative process,and gather more immune cells around the defect site to accelerate the degradation of NBGS.The degradation of NBGS provides sufficient space for the bone remodeling.Besides,calcium and phosphate released during the degradation of the scaffold can promote the mineralization of new bone tissue.The intrinsic multifunctionality of killing bone tumor cell and promoting angiogenesis and bone regeneration makes the engineered Nb2C MXeneintegrated composite scaffolds a distinctive implanting biomaterial on the efficient treatment of bone tumor.Junhui Yin Shanshan Pan Xiang Guo Youshui Gao Daoyu Zhu Qianhao Yang Junjie Gao Changqing Zhang Yu Chen 2021Nano-Micro Letters2021,13,2:5
8Effects of splined shaft bending rigidity on cylinder tilt behaviour for high-speed electrohydrostatic actuator pumps显示文摘High-speed axial piston pumps are hydraulic power supplies for electro-hydrostatic actuators(EHAs). The efficiency of a pump directly affects the operating performance of an EHA, and an understanding of the physical phenomena occurring in the cylinder/valve plate interface is essential to investigate energy dissipation. The effects of the splined shaft bending rigidity on the cylinder tilt behaviour in an EHA pump need to be considered, because the deflection and radial expansion of a steel shaft rotating at a high speed cannot be ignored. This paper proposes a new mathematical model to predict the cylinder tilt behaviour by establishing a quantitative relationship between the splined shaft deflection, the cylinder tilt angle, and the tilt azimuth angle. The moments exerted by the splined shaft are included in the equilibrium equation of the cylinder. The effects of solid and hollow splined shafts equipped in an EHA pump prototype are compared at variable speeds of 5000–10,000 r/min. With a weight saving of 29.7%, the hollow shaft is experimentally found to have almost no influence on the volumetric efficiency, but to reduce the mechanical efficiency by 0.6–2.4%. The results agree with the trivial differences of the simulated central gap heights of the interface between the two shafts and the enlargement of the simulated tilt angles by the hollow shaft. The findings could guide designs of the cylinder/valve plate interface and the splined shaft to improve both the efficiency and power density of an EHA pump.Junhui ZHANG Yuan CHEN Bing XU Min PAN Qun CHAO 2019Chinese Journal of Aeronautics2019,32,2:4
9Analysis of the efficacy of transcatheter arterial infusion chemotherapy in the treatment of pancreatic carcinoma显示文摘Objective:To evaluate the clinical efficacy of infusion of gemcitabine(GEM) and fluorouracil(5-FU)through the celiac artery and superior mesenteric artery in the treatment of pancreatic carcinoma(PC).Methods:We analyzed 20 patients diagnosed clinically or pathologically with PC,without metastases,who had an estimated survival duration of>3 months in our department from May 2009 to December 2014.Nine patients were treated directly without surgical resection of the tumor,while the other 11 patients were treated after surgery.In all patients,the femoral artery was punctured using the Seldinger technique,and a catheter was placed in the opening of the celiac artery or the superior mesenteric artery.We administered 500 mg/m2 GEM and 500 mg/m2 5-FU.Observational data included data on clinical efficacy and survival rates during the follow-up period of 3-72 months.Results:Twenty patients were treated 85 times with transcatheter arterial infusion chemotherapy(TAI).The survival rates were 80%,40%,35%,20%,10%,and 5% at 3,6,12,24,and 72 months,respectively.Conclusion: TAI chemotherapy with GEM and 5-FU may be a therapeutic option for the treatment of PC.Chunhui Nie Yuelin Zhang Guanhui Zhou Tanyang Zhou Tongyin Zhu Baoquan Wang Shengqun Chen Hongliang Wang Ziniu Yu Li Jing Junhui Sun 2021Journal of Interventional Medicine2021,4,1:4
10Phosphor-free single chip GaN-based white light emitting diodes with a moderate color rendering index and significantly enhanced communications bandwidth显示文摘To achieve high quality lighting and visible light communication(VLC)simultaneously,Ga N based white light emitting diodes(WLEDs)oriented for lighting in VLC has attracted great interest.However,the overall bandwidth of conventional phosphor converted WLEDs is limited by the long lifetime of phosphor,the slow Stokes transfer process,the resistance-capacitance(RC)time delay,and the quantum-confined Stark effect(QCSE).Here by adopting a self-assembled In Ga N quantum dots(QDs)structure,we have fabricated phosphor-free single chip WLEDs with tunable correlated color temperature(CCT,from 1600 K to 6000 K),a broadband spectrum,a moderate color rendering index(CRI)of 75,and a significantly improved modulation bandwidth(maximum of150 MHz)at a low current density of 72 A∕cm^2.The broadband spectrum and high modulation bandwidth are ascribed to the capture of carriers by different localized states of In Ga N QDs with alleviative QCSE as compared to the traditional In Ga N/Ga N quantum well(QW)structures.We believe the approach reported in this work will find its potential application in Ga N WLEDs and advance the development of semiconductor lighting-communication integration.Rongqiao Wan Xiang Gao Liancheng Wang Shuo Zhang Xiongbin Chen Zhiqiang Liu Xiaoyan Yi Junxi Wang Junhui Li Wenhui Zhu Jinmin Li 2020Photonics Research2020,8,7:3
11Enhancing phosphorus uptake efficiency through QTL-based selection for root system architecture in maize显示文摘Root system architecture(RSA) plays an important role in phosphorus(P) acquisition,but enhancing P use efficiency(PUE) in maize via genetic manipulation of RSA has not yet been reported.Here,using a maize recombinant inbred line(RIL) population,we investigated the genetic relationships between PUE and RSA,and developed P-efficient lines by selection of quantitative trait loci(QTLs) that coincide for both traits.In low-P(LP) fields,P uptake efficiency(Pup E) was more closely correlated with PUE(r =0.48-0.54),and RSA in hydroponics was significantly related to Pup E(r=0.25-0.30) but not to P utilization efficiency(Put E).QTL analysis detected a chromosome region where two QTLs for PUE,three for Pup E and three for RSA were assigned into two QTL clusters,Cl-bin3.04 a and Cl-bin3.04 b.These QTLs had favorable effects from alleles derived from the large-rooted and high-Pup E parent.Marker-assisted selection(MAS) identified nine advanced backcross-derived lines carrying Cl-bin3.04 a or Cl-bin3.04 b that displayed mean increases of 22%e26% in PUE in LP fields.Furthermore,a line L224 pyramiding Clbin3.04 a and Cl-bin3.04 b showed enhanced Pup E,relying mainly on changes in root morphology,rather than root physiology,under both hydroponic and field conditions.These results highlight the physiological and genetic contributions of RSA to maize Pup E,and provide a successful study case of developing P-efficient crops through QTL-based selection.Riliang Gu Fanjun Chen Lizhi Long Hongguang Cai Zhigang Liu Jiabo Yang Lifeng Wang Huiyong Li Junhui Li Wenxin Liu Guohua Mi Fusuo Zhang Lixing Yuan 2016Journal of Genetics and Genomics2016,43,11:3
12Optical superoscillatory waves without side lobes along a symmetric cut显示文摘Optical superoscillation refers to an intriguing phenomenon of a wave packet that can oscillate locally faster than its highest Fourier component,which potentially produces an extremely localized wave in the far field.It provides an alternative way to overcome the diffraction limit,hence improving the resolution of an optical microscopy system.However,the optical superoscillatory waves are inevitably accompanied by strong side lobes,which limits their fields of view and,hence,potential applications.Here,we report both experimentally and theoretically a new superoscillatory wave form,which not only produces significant feature size down to deep subwavelength,but also completely eliminates side lobes in a particular dimension.We demonstrate a new mechanism for achieving such a wave form based on a pair of moonlike sharp-edge apertures.The resultant superoscillatory wave exhibits Bessel-like forms,hence allowing long-distance propagation of subwavelength structures.The result facilitates the study of optical superoscillation and on a fundamental level eliminates the compromise between the superoscillatory feature size and the field of view.Yanwen Hu Shiwang Wang Junhui Jia Shenhe Fu Hao Yin Zhen Li Zhenqiang Chen 2021Advanced Photonics2021,3,4:3
13High surface area, high catalytic activity titanium dioxide aerogels prepared by solvothermal crystallization显示文摘Titanium dioxide has been considered to be one of the most effective and environmental friendly photocatalytic material.It has been widely used in photocatalytic degradation of various pollutants.As we known,an anatase crystal form typically obtained by high temperature heat treatment(>600℃),usually shows higher catalytic activity.In order to further improve the catalytic efficiency,we prepared TiO2 with a non-supercritical drying method to form a high specific surface area aerogel structure,along with an increased active contact site.However,with the inevitable of internal pores collapse in the process of high temperature crystallization,a large amount of porous structure and specific surface area is reduced.Here,to enhance the photocatalytic activity of titania,we propose a synergistic strategy to fabricate a porous titania structure with a high specific surface area.It was crystallized at a lower temperature(120℃) in a low-boiling solvent(ethanol,acetone,etc.).The lattice structure was identified by X-ray diffractometry;specific surface area(over 300 m2/g) of our sample was also measured through BET test;in the subsequent photocatalytic degradation test,the photocatalytic degradation efficiency of fabricated TiO2 is proved to be more excellent than P25 powder.By a freeze-drying/mild crystallization method,a high-specific surface area and high catalytic activity TiO2 aerogel was synthetized.This study provides some insights in the combining of crystallization and high specific surface area of titanium dioxide photocatalysis.Xian Yue Junhui Xiang Junyong Chen Huaxin Li Yunsheng Qiu Xianbo Yu 2020Journal of Materials Science & Technology2020,47,12:2
14Effect of external surface of HZSM-5 zeolite on product distribution in the conversion of methanol to hydrocarbons显示文摘The external surface of HZSM-5 zeolite was passivated by liquid siliceous deposition and by acidic sites poisoning with lepidine, respectively.Then methanol-to-hydrocarbons(MTH) reaction was investigated over the above as-prepared catalysts and the dissoluble coke on these used catalysts was analyzed by GC-MS, to study the role of the external surface of HZSM-5 in the catalytic reaction. Comparison with the experimental results based on parent ZSM-5 showed that the product distribution of MTH reaction was obviously influenced by the external surface.Evidences were listed as follows:(1) the final product on parent HZSM-5 showed higher aromatic selectivity, lower olefin selectivity, lower ratio of C2/C3+aliphatics and higher ratio of C3/C4+aliphatics than the reaction mixture produced by the sole catalysis of acidic sites in HZSM-5channel;(2) a little of pentamethylbenzene and hexamethylbenzene in the product on parent HZSM-5, was produced via multi-methylation of methylbenzene on the external surface. The above conclusion may also be suitable for MTH reaction over other zeolites with 10-ring channel.Junhui Li Yanan Wang Wenzhi Jia Zhiwen Xi Huanhui Chen Zhirong Zhu Zhonghua Hu 2014Journal of Energy Chemistry2014,23,6:2
15Self-assembled PEG-b-PDPA-b-PGEM copolymer nanoparticles as protein antigen delivery vehicles to dendritic cells:preparation,characterization and cellular uptake显示文摘Antigen uptake by dendritic cells(DCs)is a key step for initiating antigen-specific T cell immunity.In the present study,novel synthetic polymeric nanoparticles were prepared as antigen delivery vehicles to improve the antigen uptake by DCs.Well-defined cationic and acid-responsive copolymers,monomethoxy poly(ethylene glycol)-block-poly(2-(diisopropyl amino)ethyl methacrylate)-block-poly(2-(guanidyl)ethyl methacrylate)(mPEG-b-PDPA-b-PGEM,PEDG)were synthesized by reversible addition-fragmentation chain transfer polymerization of 2-(diisopropylamino)ethyl methacrylate and N-(tert-butoxycarbonyl)amino ethyl methacrylate monomers,followed by deprotection of tert-butyl protective groups and guanidinylation of obtained primary amines.1H NMR,13C NMR and GPC results indicated the successful synthesis of well-defined PEDG copolymers.PEDG copolymers could self-assemble into nanoparticles in aqueous solution,which were of cationic surface charges and showed acid-triggered disassembly contributed by PGEM and PDPA moieties,respectively.Significantly,PEDG nanoparticles could effectively condense with negatively charged model antigen ovalbumin(OVA)to form OVA/PEDG nanoparticle formulations with no influence on its secondary and tertiary structures demonstrating by far-UV circular dichroism and UV-vis spectra.In vitro antigen cellular uptake by bone marrow DCs(BMDCs)indicated using PEDG nanoparticles as antigen delivery vehicles could significantly improve the antigen uptake efficiency of OVA compared with free OVA or the commercialized Alum adjuvant.Moreover,as the surface cationic charges of OVA/PEDG nanoparticle formulations reduced,the uptake efficiency decreased correspondingly.Collectively,our work suggests that guanidinylated,cationic and acid-responsive PEDG nanoparticles represent a new kind of promising antigen delivery vehicle to DCs and hold great potential to serve as immunoadjuvants in the development of vaccines.Pan Li Junhui Zhou Pingsheng Huang Chuangnian Zhang Weiwei Wang Chen Lia Deling Kong 2017Regenerative Biomaterials2017,4,1:2
16Relationship Between Substrate Water Content and Weight Loss,Mycelium Culture Time and Hypsizygus marmoreus Growth Yields显示文摘Changes in the weight and water content of the growth substrate at different cultivation times significantly affected Hypsizygus marmoreus growth yields.Highest growth yields(132.6~146.3 g per culture) were achieved when the mycelium culture and maturation period was between 80 and 90 days,and the substrate water content was 73%~74%.Physiological maturation of H.marmoreus mycelium was correlated with the substrate water content.GAO Junhui FENG Zhiyong CHEN Hui 2008食用菌学报2008,15,3:2
17A Novel Negative Regulator of Adipogenesis: MicroRNA‐363显示文摘Lin Chen Junhui Cui Jia Hou Jie Long Cai Li Lei Liu 2014Stem Cells2014,,2:2
18Vertical Profiles of Volatile Organic Compounds in Suburban Shanghai显示文摘As Volatile Organic Compounds(VOCs)are one of the precursors of ozone,their distribution and variable concentrations are highly related to local ozone pollution control.In this study,we obtained vertical profiles of VOCs in Shanghai’s Jinshan district on 8 September and 9 September in 2016 to investigate their distribution and impact on local atmospheric oxidation in the near surface layer.Vertical samples were collected from heights between 50 m and 400 m by summa canisters using an unmanned aerial vehicle(UAV).Concentrations of VOCs(VOCs refers to the 52 species measured in this study)varied minimally below 200 m,and decreased by 21.2%from 100 m to 400 m.The concentrations of VOCs above 200 m decreased significantly in comparison to those below 200 m.The proportions of alkanes and aromatics increased from 55.2%and 30.5%to 57.3%and 33.0%,respectively.Additionally,the proportion of alkenes decreased from 13.2%to 8.4%.Toluene and m/p-xylene were the key species in the formation of SOA and ozone.Principal component analysis(PCA)revealed that the VOCs measured in this study mainly originated from industrial emissions.Yuhan LIU Hongli WANG Shengao JING Ming ZHOU Shenrong LOU Kun QU Wanyi QIU Qian WANG Shule LI Yaqin GAO Yusi LIU Xiaobing LI Zhong-Ren PENG Junhui CHEN Keding LU 2021Advances in Atmospheric Sciences2021,38,7:1
19Analysis of alkaloids in Coptis chinensis Franch by accelerated solvent extraction combined with ultra performance liquid chromatographic analysis with photodiode array and tandem mass spectrometry detections显示文摘Junhui Chen Fengmei Wang Jie Liu 2008Analytica Chimica Acta2008,613,2:1
20Atmospheric carbonyls in a heavy ozone pollution episode at a metropolis in Southwest China:Characteristics,health risk assessment,sources analysis显示文摘Ambient carbonyls were continuously observed in the field during a heavy ozone pollution episode in Chengdu, China from August 4 to August 19, 2019, and the pollution characteristics, atmospheric photochemical reactivity, human health risk, and sources of carbonyls were analyzed. Fifteen carbonyls were quantified with average total mixing ratios of 20.38 ppbv Formaldehyde(9.86 ppbv), acetone(4.41 ppbv), and acetaldehyde(3.57 ppbv) were the three most abundant carbonyls. During the heavy ozone pollution episode, the concentration of carbonyls was found to be higher on pollution days than on the clean days, and relatively higher in the daytime, especially at noon on the pollution days. This was influenced by the intensity of photochemical reactions and precipitation. The “weekend effect” with the concentration of carbonyls was higher on the weekends than on the weekdays was pointed out. Formaldehyde, acetaldehyde and hexaldehyde were the dominant oxidative species during the observation. The carcinogenic and non-carcinogenic risk values of formaldehyde and acetaldehyde were higher on pollution days than on clean days, and these values were higher compared with those of other cities in China and abroad. Long-term exposure to these compounds should therefore be avoided. Diagnostic ratios and correlation analysis together with backward trajectory analysis showed that primary emission and secondary formation accounted 66%-76% and 24%–34% of carbonyls in Chengdu, respectively, with primary emission being the main sources of carbonyls, and carbonyls from the surrounding cities and emission from natural sources also had a significant contribution to the carbonyls in Chengdu.Jiemeng Bao Hong Li Zhenhai Wu Xin Zhang Hao Zhang Yunfeng Li Jun Qian Junhui Chen Liqun Deng 2022Journal of Environmental Sciences2022,34,3:1
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