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实施《大气污染防治行动计划》对中国东部地区Pm2.5化学成分的影响

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中国科学：地球科学 2020年第4期50卷 469-482页

作者：耿冠楠肖清扬郑逸璇同丹张玉璇张小曳张强贺克斌刘阳 department of Environmental Health Rollins School of Public HealthEmory UniversityAtlantaGeorgia 30322USA 清华大学地球系统科学系北京100084 清华大学环境学院北京100084 中国气象科学研究院北京100081

为应对严重的大气细颗粒物(Pm2.5)污染,中国于2013年发布了《大气污染防治行动计划》(以下简称"大气十条"),制定了严格的污染控制措施.大气中Pm2.5化学成分的浓度变化与其前体物排放的变化直接相关,因此,分析"大气十条"实施期间中国Pm2.... 详细信息

为应对严重的大气细颗粒物(Pm2.5)污染,中国于2013年发布了《大气污染防治行动计划》(以下简称"大气十条"),制定了严格的污染控制措施.大气中Pm2.5化学成分的浓度变化与其前体物排放的变化直接相关,因此,分析"大气十条"实施期间中国Pm2.5化学成分的时空变化有助于评估控制措施的效果,并可为未来减排政策的制订提供参考.然而目前中国尚未开展Pm2.5化学成分的常规监测,对区域尺度Pm2.5化学成分的时空变化特征尚不清楚.本研究融合卫星遥感数据和空气质量模型模拟,构建了中国东部地区2013~2017年时空覆盖完整的Pm2.5化学成分浓度数据集,并据此分析了中国东部地区大气Pm2.5化学成分的时空变化特征.结果表明, 2013~2017年间,中国东部地区Pm2.5各种成分的浓度均有所下降,硫酸盐、硝酸盐、铵盐、有机碳、黑碳和其他组分的人口加权平均浓度分别从2013年的11.1、13.8、7.4、9.9、4.6和12.9μg m–3下降至2017年的6.7、13.1、5.8、8.4、3.8和9.6μg m–3.其中硫酸盐的下降幅度最大, 2017年的浓度相较于2013年下降了40%,而硝酸盐下降幅度最小,仅为5%.由此导致Pm2.5中硝酸盐比例升高,硫酸盐比例下降.在区域层面,京津冀地区Pm2.5及其化学成分的下降幅度最大.硫酸盐浓度的下降幅度与其前体物sO2排放的下降幅度相当,而sO2排放下降主要由工业部门减排主导.硝酸盐浓度的下降幅度较小,这主要是由于大气富氨条件下硫酸盐浓度降低,促进了大气中硝酸向硝酸盐的生成,从而部分抵消了NOx减排带来的成效.为更有效地控制Pm2.5污染,未来应加强对氨的减排工作.

关键词： “大气十条” Pm2.5化学成分卫星遥感

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美国煤的自燃倾向性

矿业安全与环保 1983年第1期 49-54页

作者： J.m柯契塔 ,V.R路伟 ,d.s布其斯 ,陈作宾

前言煤矿中煤的自燃一般来说是起因于煤层和采空区的缓慢氧化,在炭化程度低的褐煤、次烟煤中容易发生。予计今后开发煤矿要进一步依靠炭化程度低的煤炭,因而随之而来的便会增加煤自燃引起煤矿火灾的危险性。美国矿业局最近对于自燃... 详细信息

前言煤矿中煤的自燃一般来说是起因于煤层和采空区的缓慢氧化,在炭化程度低的褐煤、次烟煤中容易发生。予计今后开发煤矿要进一步依靠炭化程度低的煤炭,因而随之而来的便会增加煤自燃引起煤矿火灾的危险性。美国矿业局最近对于自燃的研究,主要是以烟煤为对象,进而再扩大到褐煤,次烟煤,并研究了美国各种煤自热和外界空气温度,湿度条件的关系。此处所谓的自热温度就是指煤块在绝热条件下可能发生连续放热反应的最低温度。

关键词：炭化程度褐煤绝热条件柴煤煤炭烟煤自然发火倾向性自热吸氧速度网目表面活性能美利坚合众国北美洲美国

Endophytic bacteria associated with endangered plant Ferula sinkiangensis K. m. shen in an arid land： diversity and plant growth-promoting traits

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Journal of Arid Land 2017年第3期9卷 432-445页

作者： LIU yonghong GUO Jianwei LI Li mipeshwaree d AsEm ZHANG yongguang Osama A m.ham.d Nimaichand sALAm LI Wenjun Key Laboratory of Biogeography and Bioresource in Arid Land Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Urumqi 830011 China University of Chinese Academy of sciences Beijing 100049 China Key Laboratory of Crops with High Quality and Efficient Cultivation and security Control Yunnan Higher Education Institutions Honghe University Mengzi 661100 China state Key Laboratory of Biocontrol and Guangdong Provincial Key Laboratory of Plant Resources School of Life Sciences Sun Yat-Sen University Guangzhou 510275 China Environmental science department Institute for Post Graduate of Environment Study Arish University Arish 45511 Egypt

Ferula spp. are traditional medicinal plants found in arid land. Large-scale excavation for extracting bioactive compounds from the plants in arid regions of Xinjiang over the last few years has, however, significandy decreased their distributions. due to the urgent need for preservation of these plant resources, along with the need of searching for alternative source of the useful metabolites, it is important to screen the endophytic microbial resources associated with the plant Ferula sinkiangensis K. m. shen. In the study, a total of 125 endophytic bacteria belonging to 3 phyla, 13 orders, 23 families, and 29 genera were isolated based on 16s rRNA gene sequencing data. Among the different isolates, three strains isolated from roots were potential novel species of the genera Porphyrobacter, Paracoccus and draycofatopsis. In this study, 79.4% and 57.1% of the total isolates were capable of producing indole-3-acetic acid （IAA） and siderophore, respectively. And, 40.6% of the strains inhibit the growth of fungal pathogen Afternaria alternata, 17.2% and 20.2% strains were positive for antagonism against Vertidllium dahlia 991 and V. dahlia 7, respectively. These results demonstrated that E sinkiangensis is a rich reservoir of endophytic bacterial resources with potential for production of biologically important functions such as plant growth-promoting factors.

关键词： endophytic bacteria Ferula sinkiangensis endangered species growth promoting

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HepG2 cells support viral replication and gene expression of hepatitis C virus genotype 4 in vitro

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World Journal of Gastroenterology 2006年第30期12卷 4836-4842页

作者： mostafa K El-Awady Ashraf A Tabll yasmine s El-Abd mahmoud m Bahgat Hussein A shoeb samar s youssef Noha G Bader El din El-Rashdy m Redwan maha El-demellawy moataza H Omran Wael T El-Garf said A Goueli department of Biomedical Technology National Research Center Tahrir Street PO 12622 Dokki Cairo Egypt department of medicinal Chemistry Na- tional Research Center Tahrir Street PO 12622 Dokki Cairo Egypt department of microbiology and Immunology Faculty of Pharmacy Cairo University Cairo Egypt Genetic Engineering and Biotechnology Research Institute New Borg El-Arab City Alexandria Egypt department of Pathology school of medicine University of Wisconsin Madison WI United States

瞄准：与丙肝的长期的复制建立一个房间文化系统病毒(HCV ) 染色体和病毒的抗原的表示在试管内。方法：HepG2 房间线被孵化与长期的丙肝从一个病人与浆液为它的危险性测试到 HCV。房间和上层清液在文化期间在各种各样的时间点被收获。... 详细信息

瞄准：与丙肝的长期的复制建立一个房间文化系统病毒(HCV ) 染色体和病毒的抗原的表示在试管内。方法：HepG2 房间线被孵化与长期的丙肝从一个病人与浆液为它的危险性测试到 HCV。房间和上层清液在文化期间在各种各样的时间点被收获。文化上层清液为它感染天真的房间的能力被测试。存在减(反感觉) 在房间的核心和 E1 抗原的 RNA 海滨，和察觉被 RT-PCR 和免疫学的技术(流动血细胞计数和西方的污点) 分别地检验。结果：细胞内部的 HCV RNA 首先在 d 上被检测 3 在感染以后然后能一致地在至少三个月的一个时期上在房间和上层清液被检测。新鲜房间能从有教养的感染的房间感染上层清液。流动 cytometric 分析证明表面和在房子里使用的细胞内部的 HCV 抗原表示使 polyclonal 成为了抗体(反核心，和 anti-E1 ) 。西方的污点分析证明在分子量的产生免疫性的肽的簇的表示在一个月内在 31 和 45 kda 之间延长了感染的房间的旧文化而这簇在 uninfected HepG2 房间是无法发现的。结论：HepG2 房间线产生 HCV 感染而且支持它的复制在试管内不仅。HCV 结构的蛋白质的表示能在感染的 HepG2 房间被检测。这些房间也能够流病毒的粒子进接着对 uninfected 房间变得传染的培养基。

关键词：病毒复制基因表达丙型病毒肝炎治疗

magnetic and Electrical Properties of Gd doped Ni-Cu-Zn-Fe<sub>2</sub>O<sub>4</sub>

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Advances in materials Physics and Chemistry 2018年第10期8卷 401-410页

作者： P. Venkata srinivasa Rao T. Anjaneyulu d. V. Krishna Reddy m. Rami Reddy department of Physics Acharya Nagarjuna University Guntur India department of Physics S. S. & N. College Guntur India department of Physics Narasaraopeta Engineering College Guntur India

Ni0.5Cu0.25Zn0.25GdxFe2-xO4 (x = 0.0, 0.025, 0.05, 0.075, 0.1) ferrites were synthesized using an oxalic-based precursor method. The TC for all the Ni0.5Cu0.25Zn0.25GdxFe2-xO4 (x = 0.0, 0.025, 0.05, 0.075, 0.1) samples was measured by using one of the double coil susceptibility setup. In all the samples it is observed that, at a certain temperature, susceptibility falls to zero indicating the Curie temperature (TC) and ferrimagnetic samples are converted into paramagnetic sample at that temperature. The electrical properties were investigated for these samples. dielectric properties and ρdc properties were observed to decrease with the increase in the frequency for all the Gd doped ferrite samples.

关键词： Ni-Cu-Zn-Gd Nanoferrites magnetic Properties Electrical Properties

mRI和mR波谱对小儿头部发育迟缓的研究:哪个是最恰当的成像策略?

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国际医学放射学杂志 2011年第6期 597-598页

作者： P.d.Griffiths R.Batty d.Warren A.Hart m.sharrard s.R.mordekar 朱叶青 Academic Unit of Radiology Royal Hallamshire HospitalC FloorGlossop RoadSheffield S 10 2JFUK

目的发育迟缓是儿科常见病,许多发育迟缓的患儿首选mR成像。本研究为优化mR方案和病例选择的持续审计过程的一部分。材料与方法我们对157例发育迟缓的患儿进行常规mR成像及mR波谱检查。通过观察相关病理的总检测率来分析这些措施的效果... 详细信息

目的发育迟缓是儿科常见病,许多发育迟缓的患儿首选mR成像。本研究为优化mR方案和病例选择的持续审计过程的一部分。材料与方法我们对157例发育迟缓的患儿进行常规mR成像及mR波谱检查。通过观察相关病理的总检测率来分析这些措施的效果,尤其是患儿的亚组分

关键词： mRI 发育迟缓儿科学 mR波谱脑

Performance Evaluation of Wavelength division multiplexing Photonic Analogue-to-digital Converters for High-Resolution Radar systems

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Optics and Photonics Journal 2019年第12期9卷 219-234页

作者： Pedro E. d. Cruz Tiago m. F. Alves Adolfo V. T. Cartaxo Instituto de Telecomunicações Lisboa Portugal Instituto Universitário de Lisboa (IsCTE-IUL) Lisboa Portugal

The performance of the wavelength division multiplexing (Wdm) photonic analogue-to-digital converter (AdC) used for digitization of high-resolution radar systems is evaluated numerically by using the peak signal-to-noise ratio (sNR) metric. Two different Wdm photonic AdC architectures are considered for the digitization of radar signals with 5 GHz of bandwidth (spatial resolution of 3 cm), in order to provide a comprehensive study of the compromises present when deploying radar signals with high-resolution: 1) a four-channel architecture with each channel employing an AdC with 5 Gsamples/s, and 2) an eight-channel architecture with each channel employing an AdC with 2.5 Gsamples/s. For peak powers of the pulsed source between 10 and 20 dBm and a distance between the radar antenna and the sensing object of 2.4 meters, peak sNR levels between 29 and 39 dB are achieved with the eight-channel architecture, which shows higher peak sNR levels when compared with the four-channel architecture. For the eight-channel architecture and for the same peak powers of the pulsed source, peak sNR levels between 11 and 16 dB are obtained when the distance increases to 13.5 meters. With this evaluation using the peak sNR, it is possible to assess the performance limits when choosing a specific radar range, while keeping the same resolution.

关键词： Analogue-to-digital Converter Radar signal-to-Noise Ratio Wavelength division multiplexing

Phosphor Converted White Led with Improved CRI

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Journal of Applied mathematics and Physics 2018年第4期6卷 657-662页

作者： P. J. yadav N. d. meshram C. P. Joshi s. V. moharil Kamla Nehru mahavidyalaya Sakkardara Nagpur India shri mathuradas mohota College of science Sakkardara Nagpur India Physics department Shri Ramdeobaba K. N. Engineering College Nagpur India department of Physics R.T.M. Nagpur University Nagpur India

most of the commercial white LEd lamps use blue chip coated with yellow emitting phosphor. yAG:Ce3+ phosphor is coated on blue chip to obtain white light. Though this is commercially successful, there are several drawbacks such as “halo effect”, poor colour rendition, etc. In recent years several efforts have been made to improve LEd lamp performance. In this paper modifica-tion of yAG:Ce phosphor for improving CRI, by introducing Gd3+, Pr3+ or Tb3+ at Ce3+ site is reported.

关键词： yAG Phosphors White LEd CRI and Commercial Phosphor etc.

study of Image Contrast Recovery Coefficient (CRC) of a Large Ring PET scanner

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International Journal of medical Physics, Clinical Engineering and Radiation Oncology 2019年第1期8卷 46-56页

作者： m. m. Ahasan s. Akter R. Khatun m.F. Uddin m. R. Islam H. m. Jamil A. N. monika m. A. Rahman R. P. das m. m. Rahman R. A. sharmin m. N. Khanam Institute of Nuclear medical Physics AERE Bangladesh Atomic Energy Commission Dhaka Bangladesh Atomic Energy Centre Bangladesh Atomic Energy Commission Dhaka Bangladesh Infertility Unit Department of Gynaecology & Obstetrics Bangabandhu Sheikh Mujib Medical University Dhaka Bangladesh

Image contrast recovery coefficient (CRC) of a large ring PET scanner “macroPET” was studied with septa and without septa configuration by ac-quiring data from a laboratory made 35.7 cm square phantom filled with 18-F. Images were reconstructed with simple 2d filtered back projection using Hann, hamming and Parsen filters with different cut-off frequencies aiming to investigate the influence of filter and cut-off frequency on image contrast with septa and without septa mode. Results indicate that the CRC, for both hot and cold lesions, is excellent for diameters ≥ 3 cm using cut-off frequencies > 0.4. For a 2 cm hot lesion CRC is around 0.8 to 0.9. CRC for 1 cm hot and cold lesions is ~0.3, as expected. There is surprisingly little difference between results with and without septa. For hot lesions, septa appear to improve CRC slightly, but for cold lesions CRC is slightly poorer using septa.

关键词： PET Filter septa & CRC