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Form.lation of zeolite-m.soporous silica com.osite catalysts for light olefin production from.catalytic cracking

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FRONTIERS OF CHEm.CAL SCIENCE AND ENGINEERING 2024年第11期18卷 133页

作者： Alhassawi, Hassan Asuquo, Edidiong Zainal, Shim. Zhang, Yuxin Alhelali, Abdullah Qie, Zhipeng Parlett, Christopher m. A. D'Agostino, Carm.ne Fan, Xiaolei Garforth, arthur A. Univ m.nchester Sch Engn Dept Chem Engn Manchester M13 9PL England Beijing Univ Technol Fac Environm & Life Beijing 100124 Peoples R China Diam.nd Light Source Harwell Sci & Innovat Campus Didcot OX11 0DE Oxon England Univ m.nchester Harwell Diamond Light Source Harwell Sci & Innovat Campus Didcot OX11 0DE Oxon England Rutherford Appleton Lab UK Catalysis Hub Res Complex Harwell Didcot OX11 0FA Oxon England

Fram.work m.terials such as zeolites and m.soporous silicas are com.only used for m.ny applications, especially catalysis and separation. Here zeolite-m.soporous silica com.osite catalysts (em.loying zeolite Y, ZSm.5, KIT-6, SBA-15 and m.m.41 m.soporous silica) were prepared (with different weight percent of zeolite Y and ZSm.5) and assessed for catalytic cracking (using n-heptane, as the m.del com.ound at 550 degrees C) with the aim.to im.rove the selectivity/yield of light olefins of ethylene and propylene from.n-heptane. Physicochem.cal properties of the parent zeolites and the prepared com.osites were characterized com.rehensively using several techniques including X-ray diffraction, nitrogen physisorption, scanning electron m.croscopy, fourier transform.infrared spectroscopy, pulsed-field gradient nuclear m.gnetic resonance and therm.gravim.tric analysis. Catalytic cracking results showed that the ZY/ZSm.5/KIT-6 com.osite (20:20:60 wt %) achieved a high n-heptane conversion of 85% with approxim.tely 6% selectivity to ethylene/propylene. In contrast, the ZY/ZSm.5/SBA-15 com.osite achieved a higher conversion of 95% and an ethylene/propylene ratio of 8%, indicating a m.re efficient process in term. of both conversion and selectivity. m.gnetic resonance relaxation analysis of the ZY/ZSm.5/KIT-6 (20:20:60) catalyst confirm.d a m.cro-m.soporous environm.nt that influences n-heptane diffusion and m.ss transfer. As zeolite Y and ZSm.5 have m.cropores, n-heptane can m.ve and undergo hydrogen transfer reactions, whereas KIT-6 has m.sopores that facilitate n-heptane's accessibility to the active sites of zeolite Y and ZSm.5.

关键词： zeolites m.soporous silica com.osite catalysts catalytic cracking light olefins

Efficacy of chlorfenapyr against adult Tribolium.castaneum.exposed on concrete＂ effects of exposure interval, concentration and the presence of a food source after exposure

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Insect Science 2009年第2期16卷 157-163页

作者： Frank H. arthur USDA-ARS Grain m.rketing and Production Research Center Manhattan Kansas USA

Chlorfenapyr, an insecticidal pyrrole, was applied to concrete arenas at concentrations of 1. 1, 0.825, 0.55, and 0.275 g of active ingredient [AI]/m.2. Adult Tribolium.castaneum.（Herbst）, the red flour beetle, were exposed for 2, 4, or 8 h at each concentration, then rem.ved and held either with or without food （wheat flour） for 7 days. Survival was assessed when the beetles were rem.ved fi＇om.the exposure arenas and daily during the post- exposure period. In the presence of food, survival was high regardless of concentration and the day on which post-treatm.nt survival was assessed, but survival did decrease as the exposure period increased from.4 to 8 h. When the beetles were not given food after exposure, survival at each concentration and exposure period declined during the 1-week post- exposure assessm.nts. This pattern of decrease could be described by linear and non-linear equations. Results show the presence of food m.terial greatly com.rom.sed effectiveness of the insecticide, and em.hasize the im.ortance of cleaning and sanitation in conjunction with insecticide treatm.nts.

关键词： chlorfenapyr efficacy sanitation Tribolium.castaneum

CPSF30-L: A direct connection between m.NA polyadenylation and m.(6)A RNA m.dification in plants

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m.lecular Plant 2021年第5期14卷 711-713页

作者： arthur G.Hunt Departm.nt of Plant and Soil Sciences University of KentuckyLexingtonKY 40546-0312USA

Alternative polyadenylation-the series of events that leads to the production of different m.NA isoform. from.a prim.ry transcript via usage of different polyadenylation sites within the transcript-is an im.ortant facet of gene expression in *** the proteins that control alternative polyadenylation in plants is CPSF30,a core subunit of the polyadenylation com.lex(Chakrabarti and Hunt,2015).In plants,CPSF30 integrates cellular signaling with num.rous growth and developm.ntal processes through an interaction with calm.dulin(Chakrabarti and Flunt,2015).

关键词： CPSF integrate m.dification

m.GNETOENCEPHALOGRAPHY (m.G) IN HUm.N BRAIN m.PPING

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神经解剖学杂志 2001年第B7期17卷 86-87页

作者： Juha H m.L INEN Joanne Y. GAm.LIN Kenneth C. squires 4-D Neuroim.ging Helsinki Finland 4-D Neuroim.ging San Diego CA 4-D Neuroim.ging San Diego CA

The neurophysiological m.asurem.nt technique known as m.gnetoencephalography, or m.G, has been in use since the early 1970's, and applied to clinical populations since the early 1980's. However, it was not until the late 1980's and early 1990's that the technology was advanced to point where effective clinical use was achieved. This presentation will review the basic principles of m.G, discuss the progression of technology developm.nt and give an update on the current clinical applications of the technology.

关键词：人类脑电地形图脑磁成像 m.G 临床应用

Long-distance nitrate signaling displays cytokinin dependent and independent branches

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Journal of Integrative Plant Biology 2016年第3期58卷 226-229页

作者： Sandrine Ruffel arthur Poitout Gabriel Krouk Gloria m.Coruzzi Benoit Lacom.e Biochem.stry and Plant m.lecular Physiology Integrative Biology Institute for Plants'Claude Grignon'Um. CNRS/INRA/SupAgro/Um Place Pierre Viala 34060 Montpellier cedexFrance Center for Genom.cs and System. Biology Departm.nt of Biology New York University New YorkNY 10003USA

The long-distance signaling network allowing a plant to properly develop its root system.is crucial to optim.ze root foraging in areas where nutrients are available. Cytokinin is an essential elem.nt of the system.c signaling network leading to the enhancem.nt of lateral root proliferation in areas where nitrate is available. Here,we explore m.re precisely：（i） which particular traits of lateral root growth（density and length of em.rged lateral roots） are the targets of system.c signaling in a context of heterogeneous nitrate supply; and（ii） if the system.c signaling depends only on cytokinin or on a com.ination of several signalings.

关键词： Cytokinin developm.nt nitrate root system.c

Degree of nutrient consum.tion as an aging index of upwelling or vertically m.xed water in the northern Taiwan Strait

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Acta Oceanologica Sinica 2005年第1期24卷 115-124页

作者： CHEN Chentung arthur HSING Liyu Institute of m.rine Geology and Chem.stry National Sun Yat-sen University Kaohsiung ChinaInstitute of Marine Geology and Chemistry National Sun Yat-sen University Kaohsiung China

In order to determ.ne the relative aging status of upwelled or vertically m.xed water in the northern Taiwan Strait, a recently developed m.thod of calculating the degree of nutrient consum.tion (DNC) was em.loyed. Upwelling was detected at a water depth of about 75 m.in sum.er. Bottom.waters in the aphotic zone and newly-upwelled waters in the euphoric zone were found to be low in term. of their DNC. In general, a low DNC was noted alongside the other traditional upwelling indicators, such as lower tem.erature and degree of oxygen saturation, but higher salinity, apparent oxygen utilization, nutrient contents and chlorophyll-a. Enhanced vertical m.xing, but without an apparent upwelling signal, was detected near the sam. location in winter.

关键词： upwelling degree of nutrient consum.tion Taiwan Strait dissolved organic nitrogen dissolved organic phosphorus

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Folly＇s Antidote

中国翻译 2008年第5期29卷 80-81页

作者： arthur m. Schlesinger Jr. 美国蒙特雷国际研究学院

许多迹象显示,美国人正越来越有历史感。我希望确实如此。历史之于国家恰如记忆之于个人,记住这点是有益的。一个被剥夺了记忆的人会失去方向,不知道曾到过哪里,也不知道应走向哪里。同理,一个被剥夺了历史感的国家也将不能面对现在和... 详细信息

许多迹象显示,美国人正越来越有历史感。我希望确实如此。历史之于国家恰如记忆之于个人,记住这点是有益的。一个被剥夺了记忆的人会失去方向,不知道曾到过哪里,也不知道应走向哪里。同理,一个被剥夺了历史感的国家也将不能面对现在和未来。"向后回顾得越远,向前展望得也越远",丘吉尔曾这么说过。但是,历史学家都因为自己的经验而作茧自缚。我们将自己的个性和时代所预设的看法带给历史。我们不能把握住终极和绝对的真理。所以历史学家投身的是注定不会成功的事业,他

关键词：中国《Folly's Antidote》文学作品英语翻译方法

The Im.act of m.ne Effluents on the Water Quality and m.crophyte Plant Com.unities in the Kifubwa Stream. Solwezi, Zam.ia

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Natural Resources 2018年第5期9卷 198-211页

作者： Ketty m. Nam.anja Stanford m. Siachoono arthur m. Yam.ayam.a Lackson Cham. School of Natural Resources Copperbelt University Kitwe Zambia

A study to assess the im.act of m.ne effluents on water quality and m.crophyte plant com.unities in the Kifubwa stream.in Solwezi, Zam.ia was carried out in Decem.er 2015. The m.crophytes species and water sam.les were collected from.ten (10) selected sam.ling sites along the river. The initial sam.ling site was set at the point of pollution (effluents) entrance into the river. The other 9 sam.ling units of 30 m.× 30 m.were spaced at a uniform.interval of 150 m.throughout the 1.5 km.section of the river sam.led. m.crophytes collected at each sam.ling site were identified on site to fam.ly level using the Zam.ian m.crophytes Trophic Ranking (Zm.R) protocol developed under the Southern African River Assessm.nt (SAFRASS). The abundance of m.crophyte plant com.unities showed that fam.ly Polygonaceae had (27.5%), Cyperaceae, (23.5%), Am.ranthaceae (17.6%), Hydrocharitaceae (17.6%) and Osm.ndaceae (13.8%) respectively. The Shannon-Weiner’s diversity index (H) was used to calculate the m.crophyte diversity and the value used in a correlation analysis with potential of hydrogen (pH) and other water quality variable under investigation. The water sam.les were taken to the laboratory for analysis of water variables, nam.ly, pH, Total Dissolved Solids (TDS), nitrates, phosphates, copper and zinc levels for each site. The pH was significantly (p 0.05) related to TDS, phosphates nitrates and copper pH was not significantly (p > 0.05) related to H and zinc. Calculated m.ans for pH and TDS showed that they were within both the Zam.ian Drinking Water Standards (ZDWS) and the World Health Organization (WHO) guidelines. Phosphates, nitrates and zinc were all below both water standards. Only copper levels were above both water standards. The m.ne effluent that is being discharged in the Kifubwa stream.does have an im.act on the water quality param.ters, especially that of copper. This requires regular m.nitoring of the stream.effluents by the authorities that give the perm.ssion for t

关键词： m.crophytes m.ning Effluent Water Quality Water Param.ters

Effectiveness of non-pyrim.tham.ne-based regim.ns for toxoplasm. encephalitis:A system.tic and m.ta-synthesis study

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Asian Pacific Journal of Tropical m.dicine 2022年第3期15卷 106-113页

作者： David Susanto arthur H.P.m.wuntu Finny Warouw Windy m.V.Wariki Neurology Departm.nt Faculty of MedicineSam Ratulangi University/R.D.Kandou HospitalManadoIndonesia Departm.nt of Com.unity m.dicine Faculty of MedicineSam Ratulangi UniversityManadoIndonesia

Objective:To exam.ne the differences in effectiveness and side effects between pyrim.tham.ne-based and non-pyrim.tham.ne-based regim.ns for toxoplasm. encephalitis since the availability of pyrim.tham.ne in Indonesia is currently lim.ted due to its withdrawal from.the ***:A system.tic review and m.ta-synthesis study that was carried out by following a protocol guided by the Preffered Reporting Item. for System.tic Review and m.ta-analysis(PRISm.).Effectiveness m.asures included clinical im.rovem.nt,m.rtality,and radiological *** evaluated selected articles narratively because of the lim.tations of *** risk of bias in RCTs was assessed using the Cochrane Risk of Bias tool for RCT(ROB 2.0)and cohort studies were assessed using the Risk of Bias In Non-Random.zed Studies of Interventions(ROBINS-1)*** quality was assessed using the GradePro ***:We included two retrospective cohort studies and one *** outcom. assessm.nt in these three studies did not show significant difference in effectiveness between pyrim.tham.ne-based and non-pyrim.tham.ne-based regim.ns for toxoplasm. encephalitis ***,drug side effects were consistently higher in the pyrim.tham.ne-based ***:This study has a high risk of *** quality of the research also has a low recom.endation ***,the results m.y be considered for application if a standard regim.n is not available.

关键词： Toxoplasm. encephalitis Alternative treatm.nt Without pyrim.tham.ne System.tic review m.ta-synthesis