检索结果-南通市图书馆

Science China Chemistry 2008年第8期51卷 705-708页

作者： jim cathy.k.w.LAM Jacky w Y HAEUSSLER Matthias Department of Chemistry The Hong Kong University of Science & TechnologyClear Water BayKowloonHong KongChina

This paper presents a new synthetic route to hyperbranched polymer. An arylene bipropiolate monomer,dimethylmethylenebis(1,4-phenylene) bipropiolate,was prepared by a one-step esterification reaction of bisphenol A with propiolic acid. Polycyclotrimrtization of the monomer was effected by reflux in dimethylformamide(DMF),producing a soluble hyperbranched poly(aroxycarbonylphenylene) in a good yield. The polymer was perfectly branched with a degree of branching of 100%.

关键词： cyclotrimerization regioselectivity hyperbranched polymer

Anti-amyloid antibodies in Alzheimer’s disease: what did clinical trials teach us?

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2025年第4期20卷 1092-1093页

作者： Danko Jeremic Lydia jiménez-Díaz Juan D.Navarro-López NeuroPhysiology&Behavior Lab University of Castilla-La ManchaBiomedical Research Center(CRIB)School of Medicine of Ciudad RealCiudad RealSpain

Although many causes of Alzheimer’s disease(AD)may exist,both the original amyloid cascade and tau hypotheses posit that abnormal misfolding and accumulation of amyloid-β(Aβ)and tau protein is the central event causing the ***,that conclusion could be only partly true,and there is conflicting evidence about the role of both proteins in AD,being able to precede and influence one *** researchers argue that these proteins are mere executors rather than primary causes of ***,there have been continuing refinements of both hypotheses,with alternative explanations proposed.Aβand tau proteins may be independently involved in specific neurotoxic pathways;yet there may be other crucial processes going on in early ***,accumulating evidence suggests that Aβand tau act synergistically,rather than additively in disease onset(Jeremic et al.,2021,2023a).

关键词： amyloid Alzheimer additive

SYNTHESIS OF A HYPERBRANCHED POLY(AROYLARYLENE) CONTAINING TRIAZOLE AND FLUORENE FUNCTIONALITIES BY CLICk CHEMISTRY AND METAL-FREE,REGIOSELECTIVE POLYCYCLOTRIMERIZATION

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Polymer Science 2009年第2期27卷 145-148页

作者： cathy.k.w.jim Jacky w.Y.Lam 唐本忠 Department of Chemistry The Hong Kong University of Science & TechnologyClear Water BayKowloonHong KongChina Department of Polymer Science and Engineering Key Laboratory of Macromolecular Synthesis and Functionalization of Ministry of EducationZhejiang University

A new bis(aroylacetylene) containing tfiazole and fluorene moieties is synthesized by click chemistry. Polycyclotrimerization of the monomer is catalyzed by piperidine in refluxed dioxane,furnishing a regioregular poly(aroylarylene) in a satisfactory *** hyperbranched structure of the polymer is characterized spectroscopically with satisfactory *** polymer enjoys no metal detriment and is soluble in common organic solvents such as tetrahydrofuran (THF),chloroform,dichloromethane (DCM),and N,N-...

关键词： Regioregular Click chemistry Polycyclotrimerization Hyperbranched polymer.

Synthesis and properties of poly(1-phenyl-1-octyne)s containing stereogenic and chromophoric pendant groups

在线全文

学校读者我要写书评

暂无评论

Science China Chemistry 2009年第10期52卷 1691-1702页

作者： LAM Jacky w.Y. jim cathy.k.w. kwOk Hoi Sing Department of Chemistry The Hong Kong University of Science & Technology Center for Display Research The Hong Kong University of Science & Technology

Poly(1-phenyl-1-octyne)s containing different stereogenic and chromophoric pendants {-[(C6H13)C= C(C6H4-p-CO2-R)] n -R = [(1S)-endo]-(?)-borneyl (P3), (1R,2S,5R)-(?)-menthyl (P4), -C6H4-p-(1R,2S,5R)-(?)-menthyl (P5), 2-napthyl (P6), 4-biphenylyl (P7)} have been designed and synthesized. The polymers are prepared in moderate yields by wCl6-Ph4Sn and possess high molecular weights (M w up to 64000). The structures and properties of the polymers are characterized and evaluated by NMR, TGA, UV, CD, PL, and EL analyses. All the polymers are thermally stable and their temperatures for 5% weight loss locate in the range of 300 to 416°C under nitrogen. The energy band gaps of all the polymers are ～3.0 eV. Polymers P4 and P5 show CD absorptions associated with the helicity of the polymer segments. Excitation of the THF solutions of P3–P7 by UV irradiation gives strong blue lights of ～485 nm with quantum yields higher than 20%. The thin films of the polymers also emit in the same spectral region, indicative of little aggregation-caused quenching of light emission. Multilayer EL devices with a configuration of ITO/Polymer:PVk/BCP/Alq3/LiF/Al are constructed, which emit blue lights of ～487 nm. The maximum luminance and external quantum efficiency vary with the pendant groups, with P6 exhibiting the highest external quantum efficiency of 0.16%. The spectra stability of the EL devices is outstanding and the EL peak maximum experiences little change with the applied voltage.

关键词： chiral photoluminescence polyacetylene electroluminescence helicity

Targeting harmful effects of non-excitatory amino acids as an alternative therapeutic strategy to reduce ischemic damage

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2025年第9期20卷 2454-2463页

作者： Victoria jiménez Carretero IrisÁlvarez-Merz Jorge Hernández-Campano Sergei A.kirov Jesús M.Hernández-Guijo Department of Pharmacology and Therapeutic School of MedicineUniv.Autónoma de MadridMadridSpain Ramón y Cajal Institute for Health Research(IRYCIS) Neurobiology-Research ServiceHospital Ramón y CajalMadridSpain Institute of Neurobiology Faculty of Mathematics and Natural SciencesHeinrich Heine University DüsseldorfDüsseldorfGermany Department of Neuroscience and Regenerative Medicine&Department of Neurosurgery Medical College of Georgia at Augusta UniversityAugustaGAUSA

The involvement of the excitatory amino acids glutamate and aspartate in ce rebral ischemia and excitotoxicity is ***,the role of non-excitatory amino acids in brain damage following a stroke or brain trauma remains largely *** release of amino acids by necrotic cells in the ischemic core may contribute to the expansion of the *** findings indicated that the reversible loss of field excitato ry postsynaptic potentials caused by transient hypoxia became irreversible when exposed to a mixture of just four non-excitatory amino acids(L-alanine,glycine,L-glutamine,and L-serine)at their plasma *** amino acids induce swelling in the somas of neurons and astrocytes during hypoxia,along with permanent dendritic damage mediated by N-methyl-D-aspartate *** N-methyl-D-aspartate receptors prevented neuronal damage in the presence of these amino acids during *** is likely that astroglial swelling caused by the accumulation of these amino acids via the alanine-serine-cysteine transporter 2 exchanger and system N transporters activates volume-regulated anion channels,leading to the release of excitotoxins and subsequent neuronal damage through N-methyl-D-aspartate receptor ***,previously unrecognized mechanisms involving non-excitatory amino acids may contribute to the progression and expansion of brain injury in neurological emergencies such as stroke and traumatic brain *** these pathways co uld highlight new therapeutic targets to mitigate brain injury.

关键词： cell swelling N-methyl-D-aspartate receptor non-excitatory amino acids stroke synaptic transmission

Thiol-Yne Click Polymerization

在线全文

学校读者我要写书评

暂无评论

Thiol-Yne Click Polymerization

2011年全国高分子学术论文报告会

作者： cathy.k.w.jim Department of Chemistry The Hong Kong University of Science ＆ TechnologyClear Water BayKowloonHong KongChina

＜正＞Azide-alkyne click polymerization has been a hot research topic because of the important role in plays in polymer chemistry and macromolecular *** have endeavored to develop this new polymerization *** this talk... 详细信息

关键词： Click polymerization regioselectivity stereoselectivity functional polymers

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

Click Polymerization

Click Polymerization

Understanding Business Disruption and Economic Losses Due to Electricity Failures and Flooding

2010年全国高分子材料科学与工程研讨会

作者： cathy.k.w.jim Department of Polymer Science and Engineering Zhejiang University

＜正＞Cu（I）-catalyzed alkyne-azide cycloaddition,coined as"click chemistry"by Sharpless et al.,is a powerful synthetic tool and enjoys the features of high efficiency,regioselectivity,and functionality tolerance as well as mild reaction conditions,fast reaction rates,and simple product isolation *** reaction has found widespread applications in various research areas,for

关键词： Polymer Synthesis Regioregularity Functional Polymers Polytriazoles Hyperbranched Polymers

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

International Journal of Disaster Risk Science 2019年第4期10卷 421-438页

作者： Elco koks Raghav Pant Scott Thacker jim w.Hall Environmental Change Institute University of OxfordSouth Parks RoadOxford OX13QYUK Institute for Environmental Studies Vrije Universiteit AmsterdamDe Boelelaan 10851081 HV AmsterdamThe Netherlands United Nations Office for Project Services(UNOPS) Marmorvej 512100 CopenhagenDenmark

Failure of critical national infrastructures can cause disruptions with widespread economic *** analyze these economic impacts,we present an integrated modeling framework that combines:(1)geospatial information on infrastructure assets/networks and the natural hazards to which they are exposed;(2)geospatial modeling of the reliance of businesses upon infrastructure services,in order to quantify disruption to businesses locations and economic activities in the event of infrastructure failures;and(3)multiregional supply-use economic modeling to analyze wider economic impacts of disruptions to *** methodology is exemplified through a case study for the United *** study uses geospatial information on the location of electricity infrastructure assets and local industrial areas,and employs a multiregional supply-use model of the Uk economy that traces the impacts of floods of different return intervals across37 subnational regions of the *** results show up to a300%increase in total economic losses when power outages are included in the risk assessment,compared to analysis that just includes the economic impacts of business interruption due to flooded business *** increase indicates that risk studies that do not include failure of critical infrastructures may be underestimating the total losses.

关键词： Economic impacts Flood hazard Indirect economic losses Infrastructure failure United kingdom

water and nutrient and energy systems in urbanizing watersheds

在线全文

学校读者我要写书评

暂无评论

Frontiers of Environmental Science & Engineering 2012年第5期6卷 596-611页

作者： Rodrigo VILLARROEL wALkER Michael Bruce BECkl, jim w. HALL warnell School of Forestry & Natural Resources University of Georgia Athens GA 30602-2152 USA Environmental Change Institute University of Oxford Oxford University Centre for the Environment South Parks Road Oxford OXI 3QY UK

Driven by considerations of sustainability, it has become increasingly difficult over the past 15-20 years -- at least intellectually -- to separate out the water infrastructure and water metabolism of cities from their intimately inter-related nutrient and energy metabolisms. Much of the focus of this difficulty settles on the wastewater component of the city＇s water infrastructure and its associated fluxes of nutrients （N, P, C, and so on）. Indeed, notwithstanding the massive volumes of these materials flowing into and out of the city, the notion of an urban nutrient infrastructure is conspicuous by its absence. Likewise, we do not tend to discuss, or conduct research into, ＂soilshed＂ agencies, or soilshed management, or Integrated Nutrient Resources Management （as opposed to its most familiar companion, Integrated water Resources Management, or IwRM）. The paper summarizes some of the benefits （and challenges） deriving from adopting this broader, multi-sectoral ＂systems＂ perspective on addres- sing water-nutrient-energy systems in city-watershed settings. Such a perspective resonates with the growing interest in broader policy circles in what is called the ＂water-food-energy security nexus＂. The benefits and challenges of our Multi-sectoral Systems Analysis （MSA） are illustrated through computational results from two primary case studies： Atlanta, Georgia, USA; and London, Uk. Since our work is part of the International Network on Cities as Forces for Good in the Environment （CFG; see ***）, in which other case studies are currently being initiated -- for example, on kath- mandu, Nepal we close by reflecting upon these issues of water-nutrient-energy systems in three urban settings with quite different styles and speeds of development.

关键词： cities climate change energy sector nutrientsector systems analysis resource recovery water-food-energy security

SYSTEMIC PATHOLOGIES OF CONFRONTATION:DIAGNOSING SECURITY DISRUPTION

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Systems Science and Systems Engineering 2009年第4期18卷 423-436页

作者： jim BRYANT Sheffield Business School Sheffield Hallam University

The world post-9/11 is characterised by uncertainty, fear and suspicion. Psychological confrontations amplified by the mass media have even come to dominate physical engagements between warring parties. Drama theory provides a powerful framework for understanding these interactions in much the way that game theory was able to support strategy making by autonomous players in a less inter-connected era, A model of the ＇normal＇ process leading to dramatic resolution is an essential feature of the drama theory approach and is described here. However this process can be derailed or fail in many ways. This paper reviews many of these systemic pathologies and illustrates some Of them through consideration of three high-profile cases. The conclusion is that it is important to recognise and possibly to use pathological behavior as an element of a character＇s interaction strategy.

关键词： Drama theory confrontation conflict resolution systemic pathology