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Gated container molecules

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Science China Chemistry 2011年第12期54卷 2038-2044页

作者： HOUk k.n. Department of Chemistry and Biochemistry University of California at Los AngelesLos Angeles

Donald J. Cram, the great UCLA chemist, received the nobel Prize for his discoveries about host-guest complexes . Both theoretical and experimental studies have been conducted about the nature and strength of interactions between the host and guest molecules. The concepts of constrictive binding （the activation energy of the binding process） and intrinsic binding （the free energy difference between the complex and the free host and guest molecules） were introduced to characterize different binding properties （Figure 1）

关键词：客体分子容器闸门主客体配合物加州大学诺贝尔奖相互作用结合特性

Studies on composite solid propellant with tri-modal ammonium perchlorate containing an ultrafine fraction

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Defence Technology（防务技术） 2017年第4期13卷 239-245页

作者： k.V. Suresh Babu P. k.n.ka Raju C.R. Thomas A. Syed Hamed k.n. ninan Solid Propellant Space Booster Plant Satish Dhawan Space Centre Sriharikota 524124 India Rocket Propellant Plant Vikram Sarabhai Space Centre Thiruvananthapuram 695 022 India Department of Chemistry Indian Institute of Space Science and Technology Thiruvananthapuram 695 547 India

Composite solid propellant is prepared using tri-modal Ammonium perchlorate(AP)containing coarse,fine and ultrafine fractions of AP with average particle size(APS)340,40 and 5 mm respectively,in various compositions and their rheological,mechanical and burn rate characteristics are *** optimum combination of AP coarse to fine to ultrafine weight fraction was obtained by testing of series of propellant samples by varying the AP fractions at fixed solid *** concentration of aluminium was maintained constant throughout the experiments for ballistics *** propellant formulation prepared using AP with coarse to fine to ultrafine ratio of 67:24:9 has lowest viscosity for the propellant paste and highest tensile strength due to dense pack.n. as supported by the literature.A minimum modulus value was also observed at 9 wt.%of ultrafine AP concentration indicates the maximum solids pack.n. density at this ratio of AP *** burn rate is evaluated at different pressures to obtain pressure *** of ultrafine fraction of AP in propellant increased burn rate without adversely affecting the pressure *** solid loading propellants are prepared by increased AP concentration from 67 to 71 wt.%using AP with coarse to fine to ultrafine ratio of67:24:*** solid content up to 89 wt.%was achieved and hence increased solid motor *** unloading viscosity showed a trend with increased AP content and the propellant couldn't able to cast beyond 71 wt.%of *** properties were also studied and from the experiments noticed that%elongation decreased with increased AP content from 67 to 71 wt.%,whereas tensile strength and modulus *** rate increased with increased AP content and observed that pressure exponent also increased and it is high for the propellant containing with 71 wt.%of AP due to increased oxidiser to fuel *** composite solid propellant is prepared by using burn rate modifie

关键词： Ammonium perchlorate Composite propellant Burn rate Copper chromite Iron oxide

Green ionic metal-organic frameworks as nanocatalysts for CO_(2)fixation

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nano Research 2025年第1期18卷 260-269页

作者： nuria Martín Miguel Maireles-Porcar Julián Sánchez Velandia Belén Altava Francisco G.Cirujano Eduardo García-Verdugo Departamento de Química Inorgánica y Orgánica Universidad Jaume IAv.Sos Baynats/nCastellóde la PlanaCastellón 12071Spain

Co,ni,and Zn iso-reticular coordination polymers of 2,5-dihydroxyterphthalic acid(H_(2)dot)can be rapidly obtained under room temperature and aqueous conditions using either sodium or ammonium hydroxide as the bases to deprotonate the *** use of metal bromides and tetrabutylammonium hydroxide(TBAOH)as the base allows the green synthesis of ionic metal-organic frameworks(MOFs),characterized by X-ray diffraction(XRD),Fourier transform infrared(FTIR),scanning electron microscopy(SEM),thermo gravimetric analysis(TGA),H-nuclear magnetic resonance(nMR),elemental analysis,and X-ray photoelectron spectroscopy(XPS),and employed in the pressure,solvent,and additive-free CO_(2)fixation to epoxides by its cycloaddition to epichlorohydrin,exhibiting a cooperative behavior between the MOF and the ionic liquid formed within the framework,achieving TOns of the confined tetrabutylammonium bromide(TBABr)up to 700.

关键词： metal-organic frameworks(MOFs) ionic liquids heterogeneous catalysis CO_(2)conversion

EFFECT　OF　RARE　EARTH　ELEMEnT　Er　On　STREnGTHEnInG　OF　InTERFACE　OF　Ti（C，n）　BASED　CERMETS

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维普期刊数据库

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中国有色金属学会会刊：英文版 1996年第3期6卷 136-139页

作者： Liu, n Cui, k Hu, ZH AnHUI InST TECHnOL DEPT MAT SCI & ENGNHEFEI 230069PEOPLES R CHINA HUAZHOnG UnIV SCI & TECHnOL WUHAN 430074PEOPLES R CHINA

ＥＦＦＥＣＴＯＦＲＡＲＥＥＡＲＴＨＥＬＥＭＥＮＴＥｒＯＮＳＴＲＥＮＧＴＨＥＮＩＮＧＯＦＩＮＴＥＲＦＡＣＥＯＦＴｉ（Ｃ，Ｎ）ＢＡＳＥＤＣＥＲＭＥＴＳ￥ＬｉｕＮｉｎｇ（ＤｅｐａｒｔｍｅｎｔｏｆＭａｔｅｒｉａｌｓＳｃｉｅｎ... 详细信息

ＥＦＦＥＣＴＯＦＲＡＲＥＥＡＲＴＨＥＬＥＭＥＮＴＥｒＯＮＳＴＲＥＮＧＴＨＥＮＩＮＧＯＦＩＮＴＥＲＦＡＣＥＯＦＴｉ（Ｃ，Ｎ）ＢＡＳＥＤＣＥＲＭＥＴＳ￥ＬｉｕＮｉｎｇ（ＤｅｐａｒｔｍｅｎｔｏｆＭａｔｅｒｉａｌｓＳｃｉｅｎｃｅａｎｄＥｎｇｉｎｅｅｒｉｎｇ，...

关键词： rare earth element Er Ti(C n) based cermets bending strength hardness

Impacts of PI3k/protein k.n.se B pathway activation in reactive astrocytes: from detrimental effects to protective functions

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neural Regeneration Research 2025年第4期20卷 1031-1041页

作者： Ramón Pérez-núñez María Fernanda González Ana María Avalos Lisette Leyton Cellular Communication Laboratory Programa de Biología Celular y MolecularCenter for Studies on ExerciseMetabolism and Cancer(CEMC)Instituto de Ciencias Biomédicas(ICBM)Facultad de MedicinaUniversidad de ChileSantiagoChile Advanced Center for Chronic Diseases(ACCDiS) Faculty of Chemical and Pharmaceutical Sciences&Faculty of MedicineUniversidad de ChileSantiagoChile Instituto de Ciencias Biomédicas Facultad de Ciencias de la SaludUniversidad Autónoma de ChileSantiagoChile

Astrocytes are the most abundant type of glial cell in the central nervous *** injury and inflammation,astrocytes become reactive and undergo morphological and functional *** on their phenotypic classification as A1 or A2,reactive astrocytes contribute to both neurotoxic and neuroprotective responses,***,this binary classification does not fully capture the diversity of astrocyte responses observed across different diseases and *** analysis has revealed that reactive astrocytes have a complex landscape of gene expression profiles,which emphasizes the heterogeneous nature of their *** actively participate in regulating central nervous system inflammation by interacting with microglia and other cell types,releasing cytok.n.s,and influencing the immune *** phosphoinositide 3-k.n.se(PI3k)/protein k.n.se B(AkT)signaling pathway is a central player in astrocyte reactivity and impacts various aspects of astrocyte behavior,as evidenced by in silico,in vitro,and in vivo *** astrocytes,inflammatory cues trigger a cascade of molecular events,where nuclear factor-κB serves as a central mediator of the pro-inflammatory ***,we review the heterogeneity of reactive astrocytes and the molecular mechanisms underlying their *** highlight the involvement of various signaling pathways that regulate astrocyte reactivity,including the PI3k/AkT/mammalian target of rapamycin(mTOR),αvβ3 integrin/PI3k/AkT/connexin 43,and notch/PI3k/AkT *** targeting the inactivation of the PI3k/AkT cellular signaling pathway to control reactive astrocytes and prevent central nervous system damage,evidence suggests that activating this pathway could also yield beneficial *** dual function of the PI3k/AkT pathway underscores its complexity in astrocyte reactivity and brain function *** review emphasizes the importance of employing astrocyte-exclusive models to underst

关键词： inflammation integrins neuroprotective neurotoxic phosphatidylinositol 3-k.n.se reactive astrocytes signal transduction Thy-1(CD90)

Astrocytes, reactive astrogliosis, and glial scar formation in traumatic brain injury

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neural Regeneration Research 2025年第4期20卷 973-989页

作者： María Belén Cieri Alberto Javier Ramos Laboratorio de neuropatología Molecular IBCN UBA-CONICETFacultad de MedicinaUniversidad de Buenos AiresBuenos AiresArgentina

Traumatic brain injury is a global health crisis,causing significant death and disability *** that follows traumatic brain injury has serious consequences for neuronal survival and cognitive impairments,with astrocytes involved in this *** traumatic brain injury,astrocytes rapidly become reactive,and astrogliosis propagates from the injury core to distant brain *** astroglial proteins are downregulated near the traumatic brain injury core,while pro-inflammatory astroglial genes are *** altered gene expression is considered a pathological remodeling of astrocytes that produces serious consequences for neuronal survival and cognitive *** addition,glial scar formed by reactive astrocytes is initially necessary to limit immune cell infiltration,but in the long term impedes axonal reconnection and functional *** therapeutic strategies for traumatic brain injury are focused on preventing acute ***,cannabinoids,progesterone,beta-blockers,and cerebrolysin demonstrate neuroprotective benefits but most of them have not been studied in the context of *** this review,we discuss the cell signaling pathways activated in reactive astrocytes following traumatic brain injury and we discuss some of the potential new strategies aimed to modulate astroglial responses in traumatic brain injury,especially using cell-targeted strategies with miRnAs or lncRnA,viral vectors,and repurposed drugs.

关键词： astrocyte glial scar innate immunity neuroinflammation stab injury Toll-like receptors

Sex differences in aging and injured brain

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neural Regeneration Research 2025年第10期20卷 2901-2902页

作者： Jordan n.Williamson Yuan Yang University of Illinois Urbana-Champaign Grainger College of EngineeringDepartment of BioengineeringUrbanaILUSA Carle Foundation Hospital Stephenson Family Clinical Research InstituteClinical Imaging Research CenterUrbanaILUSA University of Illinois Urbana-Champaign Beckman Institute for Advanced Science and TechnologyUrbanaILUSA northwestern University Department of Physical Therapy and Human Movement SciencesChicagoILUSA

Background:The prevalence,age of onset,and symptomatology of traumatic brain injury,stroke,and neurodegenerative diseases(such as Alzheimer’s disease(AD),Park.n.on’s disease,amyotrophic lateral sclerosis,and Huntington’s disease)differ substantially between males and *** higher prevalence of these brain disorders has been attributed to females having a greater longevity compared with *** one of the greatest risk factors of acquired brain injury(such as stroke,traumatic brain injury caused by fall)and neurodegenerative disease is age.

关键词： Huntington prevalence traumatic

Flux blended synthesis of novel Y2O3：Eu^3＋ sensing arrays for highly sensitive dual mode detection of LFPs on versatile surfaces

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Journal of Rare Earths 2018年第9期36卷 954-964页

作者： k.n. Venkatachalaiah H. nagabhushana R.B. Basavaj G.R Darshan B. Daruka Prasad S.C. Sharma Department of Physics Amrito School of Engineering Amrito Vishwa Vidyapeethom Amrita University Bengoluru 560035 India Research and Development Center Bharathiar University Coimbatore 641046 India Prof. C.n.R. Rao Centre for Advanced Material Science Tumakuru University Tumakuru 572103 India Department of Physics Acharya Institute of Graduate Studies Bangalore 560107 India Department of Physics B.M.S. Institute of Technology and Management Visveswaraya Technological University affiliated Bangalore 560064 India Honorary Professor Department of Mechanical Engineering Jain University Advisor Jain Croup of Institutions Bangalore 560069 India

In the present communication,various fluxes blended Y2 O3：Eu3＋（5 mol%） nanopowders（nPs） were successfully fabricated by solution combustion *** pattern confirms body-centered cubic structure of the prepared *** band gap（Eg） of the fabricated products was estimated and is found to be in the range of 3.13-3.32 ***（PL） emission spectra exhibit sharp and intense peaks at ～579,592,614,657,704 nm corresponding to 5 D0→7 FJ（J = 0,1,2,3 and 4） transitions of Eu3＋ *** of fluxes for enhancing the PL emissions was extensively *** studies of the prepared samples are located in pure red *** nPs were explored as a novel sensing agent for visualization of latent fingerprints（LFPs） on various surfaces including porous,semiporous and non-porous surfaces followed by powder dusting *** experiments including aging,temperature,scratching and aquatic fresh water treatment tests were performed to evaluate applicability of the fabricated *** LFPs exhibit well defined ridge details including most authenticated sweat pores are also revealed with high sensitivity,selectivity,little background hindrance and less *** results evidence that the method and fabricated nPs can be considered to be simple,rapid and economical and provide novel sensing platform for LFPs visualization in prospective forensic applications.

关键词： Fluxes Photoluminescence Latent fingerprint Sweat pores Forensic applications Rare earths

Mak.n. bridges between preclinical and clinical insights into age-related cognitive decline

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neural Regeneration Research 2025年第8期20卷 2321-2322页

作者： David VC Brito Clévio nóbrega Algarve Biomedical Center-Research Institute(ABC-RI) Campus GambelasFaroPortugal Algarve Biomedical Center-(ABC) Campus GambelasFaroPortugal Faculty of Medicine and Biomedical Sciences(FMCB) University of AlgarveGambelas CampusFaroPortugal

With people living longer,the societal impact of age-related cognitive decline is becoming more pronounced(Crimmins,2015).Thus,it is increasingly important to comprehend the cognitive shifts linked to aging-whether th... 详细信息

关键词： bridges becoming insight