检索结果-南通市图书馆

Adding new dimension to non-directed c（sp3）–H functionalizations

在线全文

学校读者我要写书评

暂无评论

Science china chemistry 2025年

作者： Konstantin p.Bryliakov Laboratory of Selective Oxidation catalysis N.D.Zelinsky Institute of Organic Chemistry RAS

Aliphatic c–H groups are among the most abundant yet least reactive functional groups in organic molecules. Nature has evolved metalloenzymes such as those of the cytochrome p450 superfamily that efficiently activate individual tertiary（3） and secondary （2） c（sp3）–H bonds in complex molecules with the highest level of regio-and stereoselectivity [1], thus encouraging studies aimed at engineering artificial metalloenzymes for synthetic applications [2].

关键词：

The Weakly potency of certain HNN Extensions of Nilpotent Groups

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Algebra colloquium 2014年第4期21卷 689-696页

作者： K.B. Wong p.c. Wong Institute of Mathematical Sciences University of Malaya 50603 Kuala Lumpur Malaysia

In this paper we give a characterization for certain HNN extensions oi suogroup separable groups with normal associated subgroups to be weakly potent. We then apply our result to show that certain HNN extensions of fi... 详细信息

关键词： weakly potent HNN extensions subgroup separable finitely generated nilpo-tent groups

Status and prosp.c.s for symmetric organic redox flow batteries

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 Energy chemistry 2025年第1期100卷 125-143页

作者： Md Al Raihan c.Adam Dyker Department of chemistry University of New Brunswick

As environmental concerns from fossil fuel consumption intensify, large-scale energy storage becomes imperative for the integration of renewable sources like wind, hydro, and solar with the electrical *** flow batteries, particularly those employing organic molecules, are positioned as a key technology for this purpose. This review explores the growing field of symmetric organic redox flow batteries(ORFBs) within this context. Unlike traditional asymmetric designs based on unique active materials for each electrode, symmetric ORFBs involve a single bipolar sp.c.es for both electrodes. This review highlights the benefits of a symmetric design, and categorizes five distinct classes of organic bipolar molecules used in both aqueous and non-aqueous solvents. By providing a comprehensive overview of their cell cycling and performance characteristics, the strengths and weaknesses of the diverse categories of bipolar molecules are highlighted for both solvent systems, as are opportunities for future development. This should guide new research directions and advance the development of practical symmetric ORFBs.

关键词： Redox flow battery Symmetric battery Organic battery Aqueous electrolyte Non-aqueous electrolyte

Acquired sensorineural hearing loss,oxidative stress,and microRNAs

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Neural Regeneration Research 2025年第9期20卷 2513-2519页

作者： Desmond A.Nunez Ru c.Guo Division of Otolaryngology–Head&Neck Surgery Department of SurgeryFaculty of MedicineThe University of British ColumbiaVancouverBCCanada Division of Otolaryngology–Head&Neck Surgery Gordon&Leslie Diamond Health Care CentreVancouver General HospitalVancouverBCCanada Faculty of Medicine–The University of British columbia VancouverBCCanada

Hearing loss is the third leading cause of human ***-related hearing loss,one type of acquired sensorineural hearing loss,is largely responsible for this escalating global health ***-induced,ototoxic,and idiopathic sudden sensorineural are other less common types of acquired hearing *** etiology of these conditions is complex and multi-fa ctorial involving an interplay of genetic and environmental *** stress has recently been proposed as a likely linking cause in most types of acquired sensorineural hearing *** non-coding RNA sequences known as microRNAs(miRNAs)have increasingly been shown to play a role in cellular hypoxia and oxidative stress responses including promoting an apoptotic *** hair cell death is a central histopathological finding in sensorineural hearing *** these cells do not regenerate in humans,it underlies the irreversibility of human age-related hearing *** EMBASE,Ovid MEDLINE,Web of Science core collection,and *** databases over the period August 1,2018 to July 31,2023 were searched with"hearing loss,""hypoxamiRs,""hypoxia,""microRNAs,""ischemia,"and"oxidative stress"text words for English language primary study publications or registered clinical *** red clinical trials known to the senior author we re also assessed.A total of 222studies were thus *** excluding duplicates,editorials,retra ctions,secondary research studies,and non-English language articles,39 primary studies and clinical trials underwent full-text *** resulted in 11 animal,in vitro,and/or human subject journal articles and 8 registered clinical trial database entries which form the basis of this narrative *** miR-34a and miR-29b levels increase with age in *** miRNAs were demonstrated in human neuroblastoma and murine cochlear cell lines to target Sirtuin 1/peroxisome proliferato r-activated receptor gamma coactivator-1-alpha(SIRT1/p Gc-1α),SIRT

关键词： hearing loss hypoxia microRNAs oxidative stress sensorineural

Kinetics of thermal decomposition of hydrated minerals associated with hematite ore in a fluidized bed reactor

在线全文

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2017年第3期24卷 229-239页

作者： p.c. Beuria S.K. Biswal B.K. Mishra G.G. Roy Institute of Minerals and Materials Technology Council of Scientific & Industrial Research Bhubaneswar-751013 India Indian Institute of Technology Kharagpur-721302 India

The kinetics of removal of loss on ignition(LOI) by thermal decomposition of hydrated minerals present in natural iron ores(i.e.,kaolinite,gibbsite,and goethite) was investigated in a laboratory-scale vertical fluidized bed reactor(FBR) using isothermal methods of kinetic *** in the FBR in batch processes were carried out at different temperatures(300 to 1200°c) and residence time(1 to 30 min) for four different iron ore samples with various LOIs(2.34wt% to 9.83wt%).The operating velocity was maintained in the range from 1.2 to 1.4 times the minimum fluidization velocity(Umf).We observed that,below a certain critical temperature,the FBR did not effectively reduce the LOI to a desired level even with increased residence *** results of this study indicate that the LOI level could be reduced by 90% within 1 min of residence time at 1100°*** kinetics for low-LOI samples(cates two different reaction mechanisms in two temperature *** lower temperatures(300 to 700°c),the kinetics is characterized by a lower activation energy(diffusion-controlled physical moisture removal),followed by a higher activation energy(chemically controlled removal of LOI).In the case of high-LOI samples,three different kinetics mechanisms prevail at different temperature *** temperature up to 450°c,diffusion kinetics prevails(removal of physical moisture);at temperature from 450 to 650°c,chemical kinetics dominates during removal of matrix *** temperatures greater than 650°c,nucleation and growth begins to influence the rate of removal of LOI.

关键词： thermal decomposition fluidized beds kinetic analysis hydrated iron ore activation energy

Study on kinetics of thermal decomposition of low LOI goethetic hematite iron ore

在线全文

学校读者我要写书评

暂无评论

International Journal of Mining Science and Technology 2017年第6期27卷 1031-1036页

作者： Beuria p.c. Biswal S.K. Mishra B.K. Roy G.G. Mineral processing Department CSIR–Institute of Minerals and Materials TechnologyBhubaneswar 751013India Indian Institute of Technology Kharagpur 721302India

In the present study, the kinetics of thermal decomposition of hydrated minerals associated in natural hematite iron ores has been investigated in a fixed bed system using isothermal methods of kinetic analysis. Hydrated minerals in these hematite iron ores are kaolinite, gibbsite and goethite, which contribute to the loss on ignition(LOI) during thermal decomposition. Experiments in fixed bed have been carried out at variable bed depth(16, 32, 48 and 64 mm),temperature(400-1200 ℃) and residence time(30,45, 60 and 75 min) for iron ore samples. It is observed that beyond a certain critical bed depth(16 mm), 100% removal of LOI is not found possible even at higher temperature and higher residence time. Most of the solid-state reactions of isothermal kinetic analysis have been used to analyze the reaction mechanism. The raw data are modified to yield fraction reacted "α" versus time and used for developing various forms of "α" functions.f(α) is the inverse of first derivative of g(α) with resp.c. to α. The study demonstrates that decomposition of hydrated mineral in hematite follows the chemical *** estimated activation energy values in all the experimental situations are found to high, of the order of 60 kJ/mol, reinstating that the reactions are indeed controlled by moving phase boundary and random nucleation.

关键词： Loss on ignition Goethite Kaolinite Gibbsite Roasting pellet feed Kinetic analysis

Multiple sclerosis is at a checkpoint: advancing the program

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2025年第3期20卷 811-812页

作者： Brandon c.Smith Jessica L.Williams Department of Neurosciences Lerner Research InstituteCleveland ClinicClevelandOHUSA Department of Biological Geologicaland Environmental SciencesCleveland State UniversityClevelandOHUSA

Multiple sclerosis(MS) is a chronic inflammatory and demyelinating disease of the central nervous system(cNS). patients with MS experience sensory and motor function loss due to myelin and/or axon damage perpetuated b... 详细信息

关键词： Hauser sclerosis damage

The interaction between membrane structure and wind based on the discontinuous boundary element

在线全文

学校读者我要写书评

暂无评论

Science china(Technological Sciences) 2010年第2期53卷 486-501页

作者： LI Ya &YE JiHong Key Laboratory of R.c. & p.c. Structures of Ministry of Education, Southeast University, Nanjing 210096, china Key Laboratory of R.c. & p.c. Structures of Ministry of Education Southeast University Nanjing China

Small disturbance potential theory is widely used in solving aerodynamic problems with low Mach numbers, and it plays an important role in engineering design. concerning structure wind engineering, the body of the structure is in a low velocity wind field, with a low viscosity of air and thin boundary layer, therefore, the tiny shear stress caused by the boundary layer can be ignored, only wind pressure being considered. In this paper, based on small disturbance potential theory, the fluid-structure interaction between the wind and membrane structure is analyzed by joint utilization of the boundary element method (BEM) and finite element method (FEM) through a loose-coupling procedure. However, the boundary of flow field to be calculated is not fully smooth, corners and edges still exist, so the discontinuous boundary element is introduced. Furthermore, because a large scale boundary element equation set with a nonsymmetrical coefficient matrix must be solved, this paper imports a preconditioning GMRES (the generalized minimum residual) iterative algorithm, which takes full advantage of the boundary element method. Several calculation examples have verified the correctness and soundness of the treatments mentioned above.

关键词： small disturbance potential theory discontinuous boundary element GMRES iterative algorithm membrane structure fluid-structure interaction

Lithium-conductive LiNbO_(3) coated high-voltage LiNi_(0.5)co_(0.2)Mn_(0.3)O_(2) cathode with enhanced rate and cyclability

在线全文

学校读者我要写书评

暂无评论

Green Energy & Environment 2022年第2期7卷 266-274页

作者： Haifeng Yu Shouliang Wang Yanjie Hu Guanjie He Le Quoc Bao Ivan p.parkin Hao Jiang Key Laboratory for Ultrafine Materials of Ministry of Education Shanghai Engineering Research Center of Hierarchical NanomaterialsSchool of Materials Science and EngineeringEast China University of Science and TechnologyShanghai 200237China christopher Ingold Laboratory Department of ChemistryUniversity College London20 Gordon StreetLondonWC1H 0AJUK Faculty of Applied Sciences Ton Duc Thang University19 Nguyen Huu ThoDistrict 7Ho Chi Minh CityViet Nam

LiNi_(0.5)co_(0.2)Mn_(0.3)O_(2)(NcM523) cathode materials can operate at extremely high voltages and have exceptional energy ***,their use is limited by inherent structure instability during charge/discharge and exceptionally oxidizing Ni^(4+)at the ***,we have developed a citrate-assisted deposition concept to achieve a uniform lithium-conductive LiNbO_(3) coating layer on the NcM523 surface that avoids self-nucleation of Nb-contained compounds in solution *** electrode-electrolyte interface is therefore stabilized by physically blocking the detrimental parasitic reactions and Ni^(4+)dissolution whilst still maintaining high Li+***,the modified NcM523 exhibits an encouraging Li-storage sp.c.fic cap.c.ty of 207.4 m Ah g-1at 0.2 c and 128.9 m Ah g-1 at 10 c over the range 3.0-4.5 ***,a 92% cap.c.ty retention was obtained after 100 cycles at 1 c,much higher than that of the pristine NcM523(73%).This surface engineering strategy can be extended to modify other Ni-rich cathode materials with durable electrochemical performances.

关键词： coating exceptional Lithium