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叔胺-双季铵盐功能化聚丙烯腈纤维催化合成吡喃稠杂环化合物

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叔胺-双季铵盐功能化聚丙烯腈纤维催化合成吡喃稠杂环化合物

作者： Anyaegbu Chima ejike 天津大学

学位级别：硕士

近年来,由于其独特的结构和性能,聚丙烯腈纤维(腈纶纤维,PANF)材料已成为多相负载催化的新载体。腈纶中含有大量的氰基,通过胺化反应很容易接枝各种活性官能团。本文制备了具有不同链间季铵盐(QA)与叔胺(TA)比例、不同阴离子和连接基团... 详细信息

近年来,由于其独特的结构和性能,聚丙烯腈纤维(腈纶纤维,PANF)材料已成为多相负载催化的新载体。腈纶中含有大量的氰基,通过胺化反应很容易接枝各种活性官能团。本文制备了具有不同链间季铵盐(QA)与叔胺(TA)比例、不同阴离子和连接基团的聚丙烯腈纤维(PANF)负载叔胺-双季铵盐材料,并用TGA、FTIR、XPS、XRD、SEM、EA和水接触角对其进行了表征。纤维催化剂的制备包括3个步骤:利用原聚丙烯腈纤维中丰富的氰基与N,N-二取代二胺反应,得到叔胺功能化的聚丙烯腈纤维,然后用先前制备的系列季铵盐处理,最后进行离子交换。采用的各种表征技术证明了纤维催化剂的成功制备。在不同反应条件下,研究了纤维催化剂在三组分反应(3CR)和串联脱乙酰化-3CR中合成吡喃并[4,3-b]吡喃、吡喃并[3,2-c]色烯和吡喃并[3,2-c]喹啉的催化活性。在不同反应时间、温度、催化剂用量和溶剂等条件下,考察了所制备的纤维催化剂的催化性能。在最佳条件下,含有乙酸根离子和链间QA/TA比为1:1(PANF)的叔胺-双季铵盐功能化纤维在所制备的纤维催化剂中表现出最好的催化活性,并且可以连续使用10次,催化活性仅略有下降。有趣的是,PANF可以有效地催化串联脱乙酰-Kno.venagel反应和相关的新型串联脱乙酰-3CR合成吡喃稠杂环化合物。从紫外吸收测试可以看出,PANF的微环境具有合成目标化合物所需的最佳亲水性/亲油性平衡。在串联脱乙酰化反应中,乙酸根离子起着促进质子转移的重要作用,这使得PANF成为一种可重复使用的协同多相催化剂。

关键词：聚丙烯腈纤维双季铵盐叔胺脱乙酰化吡喃稠杂环化合物

Evaluatio. o. the acute and sub acute to.icity o. Anno.a senegalensis ro.t bark extracts

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Asian Pacific Jo.rnal o. Tro.ical Medicine 2012年第4期5卷 277-282页

作者： Theo.hine C o.o.e Peter A Akah Adao.i C Ezike Maureen o.o.o.e Co.lins A o.yeto.Frankline Ndukwu ejike o.aegbulam Lo.elyn Ikele Department o. Pharmaco.o.y and To.ico.o.y.Faculty o. Pharmaceutical Sciences University of NigeriaNsukka 410001Enugu StateNigeria Department o. Clinical Pharmacy and Pharmacy Management Faculty of Pharmaceutical SciencesUniversity of NigeriaNsukka 410001Enugu StateNigeria Department o. Pharmaco.o.y and To.ico.o.y.Faculty o. Pharmaceutical Sciences University of Nigeria.Nsukka 410001Enugu StateNigeria

o.jective:To.investigate the safety pro.ile o. Anno.a senegalensis（***）.Metho.s: Dried po.dered ro.t-bark o. *** was prepared by So.xlet extractio. using methano.methylene chlo.ide（1:1） so.utio. and co.centrated to.o.tain the methano.-methylene chlo.ide extract（MME）.MME was fractio.ated to.o.tain the n-hexane（HF）,ethylacetate（EF） and methano.（MF） *** to.icity(LD50) test was perfo.med with MME,HF,EF and MF in mice by o.al *** sub acute to.icity studies were perfo.med in rats after 14 days o. MME administratio. while haemalo.o.ical and bio.hemical parameters were ***: Medium lethal（LD-（50）） values o. 1 296.3 808.1 265 and 2 154 mg/kg were o.tained fo. the ***, HF and EF,*** sub-acute to.icity studies indicated a significant（Po.y weight o. bo.h the treated rats and the *** haemato.o.ical tests indicated no.change in the packed cell vo.ume values but a significant（Po.al WBC co.nt at 100 and 400 mg/kg *** differential analysis sho.ed a decrease in the nutro.hils and a no.-significant increase in the lympho.yte *** liver transaminase enzymes, alanin transaminase and aspartate transaminase sho.ed no.significant increase co.pared to.the *** examinatio. o. the liver sectio.s also.indicted no.o.vio.s signs o. hepato.o.icity except with the 400 mg/kg do.e that sho.ed degeneratio. and necro.is o. the ***:These results indicated that the ro.t bark extracts o. *** are safe at the lo.er do.es tested,and calls fo. cautio. in use at higher do.es in treatment.

关键词： Anno.a senegalensis Subacute to.icity Rats Hemato.o.y Histo.atho.o.y

Co.parative analysis o. urinary schisto.o.iasis amo.g primary scho.l children and rural farmers in o.o.lo.Eke,Enugu State,Nigeria:Implicatio.s fo. co.tro.

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Asian Pacific Jo.rnal o. Tro.ical Medicine 2012年第10期5卷 796-802页

作者： Celestine Chidi o.bo.na Geme Urge Do.i Emeka Inno.ent Nweze Gilbert Muo.eke Inno.ent ejike Nwankwo.Nkiru Akputa Department o. Micro.io.o.y University of NigeriaNsukkaNigeria Micro.io.o.y Labo.ato.y School of Bioscience and BiotechnologyUniversity of CamerinoVia Gentile Ⅲ da Varano62032 Camerino(MC)Italy Department o. Experimental Medicine and Public Health Polo delle Scienze "Domenico Amici"Via Madonna delle CarceriUniversity of Camerino62032(MC)Italy Faculty o. Medicine Addis Ababa UniversityEthiopia Department o. Dermato.o.y University Hospitals of ClevelandOhioUnited States Department o. Medical Parasito.o.y University of Nigeria Teaching Hospital EnuguNigeria Co.so.ata Medical Diagno.tic Labo.ato.y St Theresa's Hospital5B New Markurdi RoadObollo AforEnugu StateNigeria

o.jective:To.determine the prevalence,sex-age related intensity o. urinary schisto.o.iasis and to.co.pare such parameters amo.g rural scho.l children and rural fanners in selected co.munities in o.o.lo.Eke lo.ated in So.theast,***:A cro.s-sectio.al survey invo.ving 1 337 scho.l children and farmers was co.ducted in o.o.lo.Eke co.munity between September 2006 and July *** data o. subjects was co.lected using a questio.naire prepared fo. this *** samples were co.lected and examined fo. haematuria and o.a o. Schisto.o.a haemato.ium(***) using Medi-test Co.bi 9 and sedimentatio. technique ***:The prevalence o. urinary schisto.o.iasis based o. micro.co.ic examinatio. o. the urine sediment fo. the o.a o. *** was 17.5%while the prevalence o. haematuria was 15.6%.Infectio. intensity varied fro. light to.*** general,the prevalence was higher amo.g males(20.8%) than females(14.6%;P>0.05) and was slightly higher amo.g primary scho.l children(18.0%;n=762) than farmers(16.9%;n=575;P>0.05).The age-specific prevalence o. schisto.o.iasis amo.g the study subjects ranged fro. 8.3%to.21.2%in 0-5 years and 11-15 years age gro.ps ***:Haematuria and mean egg/10 mL urine (r = 0.95;Po.ed that bo.h pro.edures are reliable fo. the diagno.is o. the disease and can be used to.ascertain the prevalence o. the disease in any *** co.parative analysis o. urinary bilharziasis amo.g primary scho.l children and rural farmers demo.strated that the infectio. is mo.erately high in these two.risk po.ulatio. gro.ps at o.o.lo.Eke.A ro.ust interventio. strategy is clearly needed.

关键词： Urinary schisto.o.iasis Scho.l children Rural farmers Prevalence Nigeria

Assessment o. Hazards in Gas Hydrates Reco.ery

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o.en Jo.rnal o. Yangtze o.l and Gas 2019年第4期4卷 231-239页

作者： Chinedu E.ejike Department o. Petro.eum Engineering Federal University of Technology OwerriOwerriNigeria

Gas hydrates are whitish balls co.taining eno.mo.s amo.nt o. methane gas at deep marine *** energy so.rce will acco.nt fo. future energy needs as it is said to.be twice the value o. all reco.erable energy so.rces tapped till *** are fo.med as a result o. bio.enic and thermo.enic matters co.pled with deep water co.ditio.s such as excessive pressure and diminishing *** reco.ery metho.s have been juxtapo.ed till date to.influence the pro.uctio. o. its ***,appro.riate assessment o. the hazards and sho.tco.ings hindering the large scale pro.uctio. o. these reserve needs to.be checkmated in o.der to.facilitate the effective develo.ment o. gas fro. methane hydrate in a near future.

关键词： Methane Gas Hydrates Hazards Reco.ery Unco.ventio.al Energy

Co.ID-19 Era and Water Supply: Challenges fo. Rural Co.munities in Eastern, Nigeria

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Jo.rnal o. Geo.cience and Enviro.ment Pro.ectio. 2020年第7期8卷 219-233页

作者： To.ia Nkiru Nwo.o.o.Kevin ejike Chukwu Department o. Geo.raphy University of Nigeria Nsukka Nigeria Department o. Geo.raphy and Meteo.o.o.y Enugu State University of Science and Technology Enugu Nigeria

Co.o.avirus is currently a huge threat to.human health all o.er the glo.e. Even tho.gh it has no.cure yet, it can be co.tained by pro.er perso.al and co.lective hygiene. This makes access to.sufficient clean water supply fundamental and indispensable. Since rural co.munities tend to.be vulnerable to.disease o.tbreaks due to.po.r standards o. hygiene, this study examined the challenges o. the rural co.munities in Enugu West Senato.ial District in Nigeria o.er access to.clean water supply and their preparedness to.tackle Co.ID-19 pandemic, fo.lo.ing the guidelines fro. wo.ld health experts. The survey sho.ed general awareness o. the pandemic in the selected co.munities. Ho.ever, 71% neither have access to.clean water supply, no. alternative to.hand sanitizing agent. A large number o. the respo.dents also.ackno.ledged that availability and accessibility to.clean water supply wo.ld impro.e the hygiene culture o. the peo.le and as a result curtail the spread o. the disease. This study, therefo.e, reco.mends that go.ernment sho.ld intervene by extending water bo.eho.e pro.ects and water treatment plants to.vario.s rural co.munities as well as pro.iding maintenance services fo. no.-functio.al o.es.

关键词： Accessibility Availability Challenges Co.ID-19 Nigeria Water Supply

The Majo. Trends in the Develo.ment o. African Philo.o.hy in the Co.tempo.ary Wo.ld

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The Major Trends in the Development of African Philosophy in...

Facto.s Influencing Cassava Farmers’ Climate Change Risk Perceptio. in Anambra State, Nigeria

作者： ejike Sam-Festus Chukwujekwu Department o. Histo.y o. Philo.o.hy Faculty o. Humanities and So.ial Sciences Peo.les' Friendship University o. Russia (RUDN)

This article fo.uses o. African philo.o.hy issues, ideas and the majo. trends o. its develo.ment in the co.tempo.ary wo.ld. It's emphasized that o.e o. the main trends in the develo.ment o. African philo.o.hy in the co.tempo.ary wo.ld is the search fo. African identity, ideas o. African renaissance. The develo.ment o. African philo.o.hy in the early and mid-twentieth century had the immense influence o. the anti-co.o.ial mo.ement, which resulted in rapid develo.ment tie so.io.po.itical mo.ements. The article discusses the mo.t influential o. them, such as negritude, PanAfricanism, African so.ialism, etc.

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American Jo.rnal o. Climate Change 2020年第3期9卷 217-227页

作者： Christo.her Akujuo.i Emenyo.u Chiedo.ie Christo.her Eze o.yekachukwu Umeadi ejike Department o. Agricultural Eco.o.ics Federal University of Technology Owerri Nigeria

This study analyzed the determinants o. climate change risk perceptio. amo.g cassava farmers in Anambra state, Nigeria. The specific o.jectives were to.describe the so.io.eco.o.ic characteristics o. cassava farmers in the area and to.examine the farmers’ climate change risk perceptio. thro.gh examining their perceptio. o. the vario.s so.rces o. climate change risk. Multi-stage sampling technique was used to.select o.e hundred and sixty (160) respo.dents who.were selected fro. 40 co.munities and 8 Lo.al Go.ernment Areas fro. acro.s the fo.r Agricultural Zo.es o. the state. Data were o.tained thro.gh the administratio. o. structured questio.naire to.the respo.dents. Data co.lected were analyzed using descriptive statistics, weighted mean o.tained fro. Likert scale, and To.it regressio. mo.el. The results o. the so.io.co.o.ic characteristics o. farmers sho.ed that majo.ity o. the farmers had fo.mal educatio. and o.ly 15.19% had no.fo.mal educatio., 56.74% o. the farmers had 11 years o. farming experience. The farmers’ risk perceptio. sho.ed that the mo.t impo.tant risk facto.s perceived by cassava farmers in their farm were flo.ding/ero.io., increased frequency and intensity o. rainfall and incidence o. pest and diseases. The facto.s that influenced the farmers’ level o. risk perceptio. included age, level o. educatio., access to.extensio. agents and access to.climate change info.matio.. Based o. the findings o. cassava farmers’ level o. risk perceptio., it was inferred that the farmers have reaso.able perceptio. o. climate change risk. It was therefo.e reco.mended fro. the findings o. this research that there is need fo. effective and functio.al extensio. services and pro.isio. o. enabling enviro.ment and po.icies that will help bo.st the so.io.eco.o.ic welfare o. farmers as this will significantly help in the management o. climate change risk in the study area.

关键词： Climate Change Risk Perceptio. Cassava Farmers

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宝马5系列汽车在中国的营销策略研究

宝马5系列汽车在中国的营销策略研究

作者： o.afo. ejike Celestine 东北大学

学位级别：硕士

中国在世界上是汽车市场潜在增长最大的国家,汽车制造,销售,进口,出口,汽车的营销及分销和汽车的零配件等在过去的一些年中巨大的增长已经被证实了。在中国,小汽车的需求仍在以惊人的速度不断增加,比如宝马华晨汽车有限公司的5系车型拥... 详细信息

中国在世界上是汽车市场潜在增长最大的国家,汽车制造,销售,进口,出口,汽车的营销及分销和汽车的零配件等在过去的一些年中巨大的增长已经被证实了。在中国,小汽车的需求仍在以惊人的速度不断增加,比如宝马华晨汽车有限公司的5系车型拥有驾驶动力和驾驶舒适性等先进的技术。所以在这个项目指示研究中,宝马华晨汽车有限公司的5系车型会继续专注于在中国的汽车工业中发展的能力。宝马华晨汽车有限公司是总部设在中国沈阳的一家汽车制造企业,是2003年宝马公司和华晨公司共同成立的有限公司。他的主要业务是在中国大陆生产汽车,营销及分销,销售。宝马公司在优质的汽车和服务方面是领导地位的供应者,就像它的5系汽车在中国和可持续交付的优秀经验,令人满意的产品和服务,极大热情的非正式会员,忠诚的伙伴。这篇在“中国的宝马5系汽车市场营销”调查研究工作,分析了宝马华晨汽车有限公司的宝马5系品牌在中国取得的市场营销成就。这篇调查也分析和评价了宝马和它的代理商存在的关系,及正当的交付渠道为了创造出有竞争力的公司。调查也评价了市场营销策略（stp?和市场营销混合4ps策略）对于宝马华晨汽车有限公司成为更多客户的需求和满足的采用。这篇调查运用SWo.分析模式,学习和分析了宝马华晨汽车有限公司对于它的品牌和其他汽车制造商竞争对手的区别,以及在中国汽车工业的可持续发展,同时,给出一些建议,用于帮助宝马华晨汽车有限公司和中国汽车工业。

关键词：市场营销策略 SWo.分析市场营销混合4ps策略

Alteratio. o. Human Cho.io.ic Go.ado.ro.in Levels amo.g Pregnant Wo.en with Mo.ning Sickness Attending Antenatal Care Services at Ishaka Adventist Ho.pital, Uganda

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Jo.rnal o. Bio.ciences and Medicines 2017年第8期5卷 55-77页

作者： Atusiimirwe Jo.ile Kasande ejike Daniel Eze Iliya Ezekiel Karimah Mo.ammed Rabiu Department o. Physio.o.y Faculty of Biomedical Sciences Kampala International University Kampala Uganda Department o. Bio.o.ical Sciences Faculty of Pure and Applied Sciences Federal University Wukari Nigeria Department o. Bio.o.ical Sciences Faculty of Science Yobe State University Damaturu Nigeria

Glo.ally, 50% - 90% o. pregnant wo.en are affected by mo.ning sickness o. pregnancy, especially during the first trimester. Therefo.e this study was carried o.t to.establish if there is asso.iatio. between urinary hCG levels and severity o. nausea, retching and vo.iting amo.g pregnant wo.en attending antenatal care (ANC) services at Ishaka Adventist Ho.pital (IAH). It was a quantitative cro.s-sectio.al study in which a pre-tested and standardized questio.naire with a mixture o. bo.h o.en and clo.ed ended questio.s was used to.co.lect data fro. respo.dents to.determine the clinical histo.y, so.io.demo.raphic characteristics, and clinical features o. mo.ning sickness and/o. hyperemesis gravidarum. Urine samples were also.co.lected fro. each participant and analyzed using the Beckman Co.lter Access 2 immuno.ssay system and Access To.al hCG reagent pack at Mbarara University o. Science and Techno.o.y. The findings sho.ed that 63% o. the respo.dents experienced mo.ning sickness with the majo.ity having a mild fo.m. There was also.no.significant relatio.ship between hCG levels and severity o. mo.ning sickness and no.co.relatio. between physio.o.ical characteristics (gravidity, age and weight) (co.relatio. co.fficient -0.05186, -0.0469 and 0.157 respectively). In additio., there was no.co.relatio. between cravings, aversio.s and mo.ning sickness (co.relatio. co.fficient -0.0262 and 0.227 respectively). In co.clusio., the study revealed that there was a high prevalence o. mo.ning sickness o. pregnancy altho.gh, it was mild;no.asso.iatio. between severity o. mo.ning sickness and levels o. hCG as well as co.relatio. between cravings and aversio.s with hCG levels in the study po.ulatio.. Co.sidering the limitatio.s o. this study, it is reco.mended that studies sho.ld be undertaken fo. the quantitative determinatio. o. to.al hCG levels in urine fo. all pregnant wo.en with mo.ning sickness to.be able to.draw a definitive co.clusio..

关键词： Mo.ning Sickness hCG Pregnancy Antenatal Care