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Li2SiO3 fast microwave-assisted hydrothermal synthesis and evaluation of its water vapor and c02 absorption properties

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Particuology 2016年第1期14卷 129-137页

作者： J. Ortiz-Landeros R. Lopez-Juarez i.c, Romero-ibarra H. Pfeiffer H. Balmori-Ramirez c. Gomez-Yanez Department of MetaUurgical and Materials Engineering National Polytechnic Institute ESIQIE-IPN UPALM Campus Instituto Politecnico NacionalAvenue 07738 Mexico City Mexico Materials Research institute Morelia campus National Autonomous University of Mexico Old Pdtzcuaro road 8701 58190 Morelia Michoacdn Mexico Department of chemistry Metropolitan Autonomous University Iztapalapa Campus San Rafael Atlixco Avenue 186 09340 Mexico City Mexico Materials Research institute National Autonomous University of Mexico Cd Universitaria Campus 04510 Mexico City Mexico

A series of lithium metasilicate （Li2SiO3） powder materials has been successfully synthesized by the microwave-assisted hydrothermal route using lithium hydroxide and tetraethyl-orthosilicate-derived sol precursors. ceramic powders were obtained under hydrothermal conditions of autogenous pressure in the presence of a nonionic surfactant. The production of pure and well-crystallized Li2 SiO3 using very short reaction times at low temperatures was shown by X-ray diffraction, scanning electron microscopy, and N2 adsorption-desorption analyses. Synthesized Li2SiO3 particles were nanocrystalline and exhibited different morphologies and specific surface areas depending on the synthesis conditions. Additionally, the capability of selected Li2SiO3 samples to absorb H20 and cO2 was evaluated via thermogravimet- ric analyses by varying the temperature, carrier gas, and water vapor concentration. Li2SiO3 particles exhibited interesting textural and morphological characteristics that make them suitable for use as a cO2 absorbent and which suggest that they also have the potential to be used in other applications.

关键词： cO2 capture Lithium metasilicate Hydrothermal synthesis Thermal analysis

Groundwater occurrence and flow patterns in the ishiagu mining area of southeastern Nigeria

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Frontiers of Earth Science 2012年第1期6卷 18-28页

作者： i.c.ezekwe E.ODUBO G.N.cHiMA i.S.ONWUcHEKWA Department of Geography and Environmental Management Niger Delta UniversityWilberforce IslandPMB 071YeneganaNigeria Department of Geography and Planning Abia State UniversityPMB 2000UtumNigeria

The ishiagu area is a water scarce region and has played host to mining activities for more than four decades. Mining-related activities have become a threat to potable water supply in the area. This paper is an attempt to show the extent of this threat and in particular, investigate the regional groundwater occurrence and flow pattem based on GPS, water well and geological data. This basin- wide model can be used for further groundwater assess- ment, pollution control and contaminant management. Groundwater occurs between 2.4 and 9 m in the Lekwesi- Lokpaukwu area; 1.5-3.7 m in the Ndi-Ugbugbor-Ayaragu axis and 1.2-4.6 m in the ishiagu area. Recharge areas i.clude the Leru-Amaubiri-Lekwesi sandstone hills and the ihetutu-Ugwuajirija mine field. While the ultimate sink of contamiants is the ivo River system, other di.charge axis is the ishiagu-Ayaragu axis and the Ogwor Ndi- Ugbugbor zone. An unconfined and a confined （〉 10） ci.culation groundwater system was inferred, and flow model reveals that a large part of ishiag-Ayaragu and Ndi- Ugbugbor part of the study area suffer polluted recharge from the Pb/Zn mining area. Groundwater was also subjected to hierarchical cluster analysis and the existence of 3-4 hydrological regimes, which revealed： Unpolluted recharge areas, areas affected by polluted recharge, a deep water and shallow water ci.culation and mine effluents.

关键词： groundwater flow mining heavy metals,pollution cluster analysis ishiagu Nigeria

TDS-Eh graph analysis： a new water quality index and rural water supply implications of a river affected by mining in south-eastern Nigeria

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Frontiers of Earth Science 2012年第1期6卷 66-74页

作者： i.c.ezekwe A.O.AiSUBEOGUN G.N.cHiMA E.ODUBO Department of Geography and Environmental Management Niger Delta UniversityWilberforce IslandPMB 071Yenegoa Nigeria Department of Geography and Planning Abia State UniversityPMB 2000UturuNigeria

The ivo River Basin of south-eastern Nigeria is a water scarce and mining region, which suffers from water scarcity. The influence of mining activities on the quality of the ivo River and its capacity for community water supply was investigated. Also the efficacy of TDS-Eh graph in explaining water quality was presented. Results indicated that the TDS-Eh graph highlights subtle chemical relationships which control water quality and provide a simple but generic pollution index for rapid water quality assessment. it was also di.covered that the ivo River could become an adequate alternative to groundwater as a source of rural water supply in the study area with an estimated average daily di.charge of 6726000L and a rural population of less than 200000 persons. The ivo River meets the WHO drinking water standards in 20 physico- chemical water quality parameters （pH, temperature, conductivity, turbidity, salinity, TDS, Eh, alkalinity, chloride, nitrate, sulfate, phosphate, calcium, magnesium, iron, manganese, zi.c, lead and cadmium） analyzed and can therefore （with little treatment） provide up to 133.4% of average community water demand and 83.8% of maximum community water demand. The. impact of mining on ivo River quality was found to have been moderated by the presence of carbonate rocks which may have enhanced the precipitation of heavy metals from the river.

关键词： TDS-Eh graph water quality mining ruralwater supply ivo River Nigeria

Status and prospects for symmetric organic redox flow batteries

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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 species for both electrodes. This review highlights the benefits of a symmetric design, and categorizes five disti.ct 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

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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 i.creasingly been shown to play a role in cellular hypoxia and oxidative stress responses i.cluding 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,""i.chemia,"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 i.crease 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

Multiple sclerosis is at a checkpoint: advancing the program

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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

Angular Differential cross-Section for ionization of Helium in c^6＋ ion collision

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chinese Physics Letters 2004年第7期21卷 1258-1261页

作者： A.c.Gagyi-Palffy i.F.Barna L.Gulyas K.Tokesi DepartmentofTheoreticalPhysics UniversityofBucharestRomania Max-Planck-instituteforPhysicsofcomplexSystems NothnitzerStr.38O1187DresdenGermany instituteofNuclearResearch HungarianAcademyofScience(ATOMKI)1-1-4001DebrecenPOBox51Hungary

With the help of the density operator, the angular differential cross-section for ionization of helium is calculated within the framework of the one-centre atomic-orbital close-coupling method. We consider a naked c6+ ion as projectile with an energy of 2.5MeV/a.u. Our result agrees well with the experimental data and the other theoretical calculations such as the first Born approximation, various Distorted Wave models and the classical trajectory Monte carlo simulation.

关键词： Monte carlo methods

Solar-driven cO_(2) conversion to methane and methanol using different nanostructured cu_(2)O-based catalysts modified with Au nanoparticles

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Journal of Energy chemistry 2024年第4期91卷 287-298页

作者： João Angelo Lima Perini Lilian D.Moura Torquato Juliana Fde Brito Gustavo A.Andolpho Mateus A.Gonçalves Leonardo D.De Angelis Lucas D.Germano Susana i.córdoba de Torresi Teodorico c.Ramalho Maria V.Boldrin Zanoni São Paulo State University(UNESP) Institute of ChemistryRua Prof.Francisco Degni55AraraquaraSP 14800-060Brazil National institute of Alternative Technologies for Detection Toxicological Evaluation and Removal of Micropollutants and Radioactive Substances(INCT-DATREM)São Paulo State University(UNESP)Institute of ChemistryRua Prof.Francisco Degni55AraraquaraSP 14800-060Brazil Laboratory of Molecular Modelling Department of ChemistryNatural Sciences InstituteFederal University of LavrasLavrasMG 37200-900Brazil Department of chemistry Faculty of ScienceUniversity of Hradec KrálovéHradec Králové50003Czech Republic instituto de Química Universidade de São PauloAv.Prof.Lineu Prestes 74805508-080São PauloSPBrazil

This work describes the use of TiO_(2)nanotubes-based electrodes(TNT)modified with cu_(2)O nanostructures and gold nanoparticles for the photoelectroreduction of cO_(2)to produce value-added compounds.A thin layer of polydopamine was used as both an adherent agent and an electron transfer mediator,due to itsπ-conjugated electron *** highest production yield was achieved using a TNT@PDA/Nc/Au40%electrode,with Faradaic efficiencies of 47.4%(110.5μM cm^(-2))and 27.8%(50.4μM cm^(-2))for methanol and methane,*** performance of the photoelectrodes was shown to be cu_(2)O facet-dependent,with cubic structures leading to greater conversion of cO_(2)to methanol(43%)and methane(27%),compared to the octahedral morphology,while a higher percentage of metallic gold on the nanostructured cu_(2)O surface was mainly important for *** functional theory(DFT)calculations supported these findings,attributing the superior photoelectrocatalytic performance of the TNT@PDA/Nc/Au40%electrode for cH4generation to the formation of an OcH3intermediate bonded to Au *** using isotope-labeling and analysis by gas chromatograph-mass(Gc-MS)demonstrated that13cO_(2)was the source for photoelectrocatalytic generation of13cH3OH and13cH313cH2OH.

关键词： cu_(2)O nanocubes Photoelectrocatalysis Polydopamine cO_(2) photoelectroreduction DFT calculations

Zero-Order Release Profiles from A Multistimuli Responsive Electro-conductive Hydrogel

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Journal of Biomaterials and Nanobiotechnology 2012年第2期3卷 262-268页

作者： Suelen H.Takahashi Luiz M.Lira Susana i.córdoba de Torresi instituto de Química Universidade de Sao Paulo Brazil

Electroconductive hydrogels has been extensively studied in drug delivery systems because they combine the properties of hydogels with the conducting polymers in only one material. in this work, pyrrole was polymerized electrochemically into poly(acrylic acid) hydrogel. This material kept the swelling properties that are characteristic of hydrogels and the electroactivity of the conducting polymers. The hydrogel (with and without the conducting polymer) swelling degree depends on both the ionic strength and pH. As this material is responsive to changes in the electrical potential, pH and ionic strength, the safranin release presented different delivery profiles, in accordance to variations and combinations of these stimuli. The most interesting result was the achievement of the linear safranin release indicating a zero-order kinetics.

关键词： Hydrogels conducting Polymers controlled Release