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Kinetics of the Reaction of 2-Chloro-3,5-dinitrobenzotriflouride with Aniline in Toluene and Methanol-Toluene Mixed Solvents

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Chinese Journal of Chemistry 2012年第1期30卷 109-114页

作者： fathalla Magda f. Chemistry Department Faculty of ScienceAlexandria UniversityP.O.426 IbrahimiaAlexandria 21321Egypt

Kinetics of the reaction of 2-chloro-3,5-dinitrobenzotriflouride with aniline were studied in toluene, metha- nol-toluene binary solvents, benzene and chloroform. The reaction in toluene exhibits third-order kinetics consistent with aggregates of aniline. Thermodynamic parameters AH#, AS# and AG# are calculated and discussed for the reaction of 2-chloro-3,5-dinitrobenzotriflouride with aniline in methanol-toluene. Molecular complexes between aniline and the substrate are rejected spectrophotometricaly. The mechanism is studied and compared with the reac- tion in presence of pyridine. It shows an amine dependence and formation of homo and/or hetero mixed aggregates between aniline and pyridine i.e. dimer mechanism.

关键词： kinetics 2-chloro-3,5-dinitrobenzotriflouride methanol-toluene

Uncertainty relations for general phase spaces

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frontiers of physics 2016年第3期11卷 51-60页

作者： Reinhard f. Werner Institut fiir Theoretische Physik Leibniz Universitiit Hannover Germany

We describe a setup for obtain!ing uncertainty relations for arbitrary pairs of observables related by a fourier transform. The physical examples discussed here are the standard position and momentum, number and angle, finite qudit systems, and strings of qubits for quantum information applications. The uncertainty relations allow for an arbitrary choice of metric for the outcome distance, and the choice of an exponent distinguishing, e.g., absolute and root mean square deviations. The emphasis of this article is on developing a unified treatment, in which one observable takes on values in an arbitrary locally compact Abelian group and the other in the dual group. In all cases, the phase space symmetry implies the eciuality of measurement and preparation uncertainty bounds. There is also a straightforward method for determining the optimal bounds.

关键词： uncertainty relations phase space measurement uncertainty

Premature axon-oligodendrocyte interaction contributes to stalling of experimental axon regeneration after injury to the white matter

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Neural Regeneration Research 2024年第3期19卷 469-470页

作者： Ephraim f.Trakhtenberg Department of Neuroscience University of Connecticut School of MedicineFarmingtonCTUSA

Studies from nearly 3 decades ago suggested that,in the central nervous system(CNS),myelination of axons by oligodendrocytes not only helps improve axonal conductivity but also stabilizes circuitry(Colello and Schwab,1994).Over the years,myelin sheaths produced by oligodendrocytes have been found to contain multiple molecules that are inhibitory to axonal growth(e.g.,MAG,NogoA,OMgp,Semaphorins)(Yiu and He,2006;Silver et al.,2014).After white matter injury in the adult CNS,myelin debris from damaged axons and dead oligodendrocytes accumulates in the forming glial scar and exposes these myelin-associated axon growth-inhibitory molecules to the injured axonal stumps,thereby contributing to the inhibition of axonal *** development,CNS axons reach their postsynaptic targets and stop growing before oligodendrocytes appear and myelinate them(foran and Peterson,1992;Dangata et al.,1996).Therefore,myelin-associated axon growth-inhibitory molecules interacting with already grown axons during myelination were thought to block axons from promiscuous sprouting and miswiring,thereby stabilizing neural circuitry in the CNS(Colello and Schwab,1994).

关键词： thereby white injury

Hebbian plasticity:the elusive missing link at the heart of Alzheimer’s disease pathogenesis?

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Neural Regeneration Research 2023年第1期18卷 123-124页

作者： Alexander f.Jeans Department of Pharmacology University of OxfordOxfordUK

The amyloid cascade hypothesis of Alzheimer’s pathogenesis:The amyloid cascade hypothesis of Alzheimer’s disease(AD)pathogenesis will shortly celebrate its thirtieth birthday(Hardy and Higgins,1992).Based on abundant genetic and biochemical evidence,it proposes that deposition of the amyloid-β(Aβ)peptide in brain parenchyma is an essential upstream trigger in AD pathogenesis that drives a cascade of events,specifically including the recruitment and pathological hyper-phosphorylation of the micro-tubule-associated protein tau,that culminate in derangement of synaptic function and,eventually,neuronal death.

关键词： pathogenesis Alzheimer eventually

fORGING ASIA′S GLOBAL TRANSPARK IN THE PEARL RIVER DELTA AT ZHUHAI

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Chinese Geographical Science 2003年第4期13卷 300-309页

作者： Victor f S SIT .

The main purpose of the paper is to introduce the concept of the Global TransPark (GTP). It is a critical time to develop air logistics infrastructure in the New Economy. The paper also presents a brief review of the air cargo industry in the Asian-Pacific region and China,in particular China’s development in the industry as its economy has grown rapidly and globalized in the past two decades. The paper argues that China needs to develop a GTP to support its future growth,and explains why the Pearl River Delta-Hong Kong-Macao city-region or Extended Metropolitan Region (EMR) is the best location. finally,it proposes that Zhuhai Airport,one of the five airports in the EMR,is the best site for the GTP. New policies from Chinese government as well as close cooperation between local governments of Guangdong and the two Special Administrative Regions of Hong Kong and Macao will be needed to make the establishment of the GTP possible.

关键词： Global TransPark airport air cargo transport Hong Kong Extended Metropolitan Region the Pearl River Delta New Economy

Early stages of non-classic crystal growth

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Science China Chemistry 2011年第12期54卷 1867-1876页

作者： GREER Heather f. EaStChem School of ChemistryUniversity of St Andrews

Investigation of early stages of crystal growth revealed that crystal growth in some systems may not follow the classic *** the early stages of inorganic crystal growth,precursor molecules and/or nanocrystallites may aggregate into large and disordered particles with the assistance of some polymers or *** crystallization of these aggregates would then take place to form shells with high crystallinity and density,followed by an extension of the crystallization from surface to *** so-called reversed crystal growth mechanism has been found in crystallization of several inorganic compounds including zeolites,perovskites,metals and metal oxides,and will be identified in more material *** establishment of this new crystal growth route gave us more freedom to control the morphology of crystals and to understand the formation mechanism of many natural *** article gives a brief review of the recent research in this field by featuring some typical examples of the reversed crystal growth.

关键词： reversed crystal growth hollow crystals core-shell particles electron microscopy

Multiscale stochastic finite element method on random field modeling of geotechnical problems- a fast computing procedure

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frontiers of Structural and Civil Engineering 2015年第2期9卷 107-113页

作者： Xi f. XU School of Civil Engineering Beo'ing Jiaotong University Beijing 100044 China

The Green-function-based multiscale stochastic finite element method (MSfEM) has been formulated based on the stochastic variational principle. In this study a fast computing procedure based on the MSfEM is developed to solve random field geotechnical problems with a typical coefficient of variance less than 1. A unique fast computing advantage of the procedure enables computation performed only on those locations of interest, therefore saving a lot of computation. The numerical example on soil settlement shows that the procedure achieves significant computing efficiency compared with Monte Carlo method.

关键词： multiscale finite element settlement perturbation random field geotechnical

Artificial Intelligence Based Threat Detection in Industrial Internet of Things Environment

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Computers, Materials & Continua 2022年第12期73卷 5809-5824页

作者： fahad f.Alruwaili College of Computing and Information Technology Shaqra UniversitySharqaSaudi Arabia

Internet of Things(IoT)is one of the hottest research topics in recent years,thanks to its dynamic working mechanism that integrates physical and digital world into a single *** technology,applied in industries,is termed as Industrial IoT(IIoT).IIoT has been found to be highly susceptible to attacks from adversaries,based on the difficulties observed in IIoT and its increased dependency upon internet and communication *** or accidental attacks on these approaches result in catastrophic effects like power outage,denial of vital health services,disruption to civil service,etc.,Thus,there is a need exists to develop a vibrant and powerful for identification and mitigation of security vulnerabilities in *** this view,the current study develops an AI-based Threat Detection and Classification model for IIoT,abbreviated as AITDC-IIoT *** presented AITDC-IIoT model initially pre-processes the input data to transform it into a compatible *** addition,WhaleOptimizationAlgorithm based feature Selection(WOA-fS)is used to elect the subset of ***,Cockroach Swarm Optimization(CSO)is employed with Random Vector functional Link network(RVfL)technique for threat ***,CSO algorithm is applied to appropriately adjust the parameters related to RVfL *** performance of the proposed AITDC-IIoT model was validated under benchmark *** experimental results established the supremacy of the proposed AITDC-IIoT model over recent approaches.

关键词： Security industrial internet of things threat detection artificial intelligence feature selection

The embryology of persistent cloaca and urogenital sinus malformations

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Asian Journal of Andrology 2020年第2期22卷 124-128页

作者： David f M Thomas University of Leeds LeedsWest Yorkshire LS29JTUK

Cloacal malformations are characterized by the confluence of the lower urinary tract,the female reproductive tract,and the rectum to create a common channel with a single opening on the *** presence of a cloaca is a normal phase of early human embryological *** the 4^th and 7^th weeks of gestation,the cloaca undergoes subdivision to form the hindgut and urogenital *** of this process results in the congenital anomaly termed persistent cloaca(PC).The term urorectal septum malformation sequence(URSMS)is also used to describe this *** classic description of this process which is still cited in many standard textbooks dates from the 19th ***,this has been increasingly called into question by the findings of studies using modern scientific *** sinus anomalies are defined by the confluence of the urethra and vagina to form a common channel of varying length with a single perineal *** this condition,the anorectal canal opens separately on the *** presence of a urogenital sinus represents a transient phase of the normal development of the lower genital tract in the female ***,the form of urogenital sinus most commonly encountered in the developed world is a feature of disordered sexual differentiation and does not arise simply from the persistence of the anatomical structure which is a feature of normal fetal development.

关键词： cloaca embryology urogenital sinus