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Heavy metal concentrations in soils and plants in the vicinity of Arufu lead-zinc mine, Middle Benue Trough, Nigeria

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c.i.ese Journal Of Geochemistry 2010年第2期29卷 167-174页

作者： Nganje T.N. Adamu c.i. Ukpong E.E. Department of Geology University of Calabar Formerly Department of Geology University of Calabar

This study focused on the influence of base metal mining on heavy metal levels in soils and plants in the vicinity of Arufu lead-zinc mine, Nigeria. Soil samples (0-15 cm depth) and plant samples were collected from cul-tivated farmlands in and around the mine, the unmineralized site and a nearby forest (the control site). The samples were analyzed for heavy metals (Fe, Zn, Mn, cu, Pb, cr and cd) by Atomic Absorption Spectrophotometry (AAS). The physical properties of soils (pH and LOi) were also measured. Results showed that soils from cultivated farm-lands have neutral pH values (6.5-7.5), and low organic matter contents (cd in culti-vated soils were higher than the concentrations obtained from the control site. These heavy metals are most probably sourced from mining and agricultural ac.i.ities in the study area. Heavy metal concentrations measured in plant parts decreased in the order of rice leaves>cassava tubers>peelings. in the same plant species, metal levels decreased in the order of Zn>Fe>Mn>cu>Pb>cr>cd. Most heavy metals were found in plant parts at average concentrations normally observed in plants grown in uncontaminated soil, however, elevated concentrations of Pb and cd were found in a few cassava samples close to the mine dump. A stepwise linear regression analysis identified soil metal contents, pH and LOi as some of the factors influencing soil-plant metal uptake.

关键词：土壤重金属含量土壤样品植物样本铅锌矿尼日利亚原子吸收光谱法线性回归分析 amp

Evaluation of hydrogeochemical characteristics of groundwater in parts of the lower Benue Trough,Nigeria

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c.i.ese Journal Of Geochemistry 2010年第4期29卷 398-406页

作者： Nganje T.N. Adamu c.i. Ugbaja A.N. Amah A.E. Department of Geology University of Calabar

The aim of this work is to evaluate the hydrogeochemical characteristics of groundwater in parts of the lower Benue Through in Nigeria as well as to evaluate the variation in groundwater chemistry data and the suitability of the groundwater for drinking and other domestic *** was based on chemical analyses of 44 water samples from existing wells and boreholes in the study *** the statistical analysis(wide ranges,median and standard deviation),it is obvious that there are significant variations in the quality/composition of groundwater in the period of *** calculated SAR,Na% and RSc values indicated that the water is of excellent to good quality and is suitable for *** and HcO3 are dominant with respect to the chemical composition of the *** the basis of water chemistry,hydrochemical indices and factor analysis the dominant controls or processes affec.i.g the distribution of geochemical variables in the study area have been shown to be water/rock interac.i.n which is mainly controlled by carbonate and silicate dissolution as well as anthropogenic.i.fluence to a lesser *** processes include cation exchange reac.i.ns and reverse ion exchange to a minor extent.

关键词：水文地球化学特征饮用地下水尼日利亚离子交换反应水化学指标海槽评价特别行政区

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 ac.i.e 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 distinct classes of organic bipolar molecules used in both aqueous and non-aqueous solvents. By providing a comprehensive overview of their cell cyc.i.g 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 direc.i.ns and advance the development of prac.i.al 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 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 collec.i.n,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 c.i.ical *** red c.i.ical trials known to the senior author we re also assessed.A total of 222studies were thus *** excluding duplicates,editorials,retra c.i.ns,secondary research studies,and non-English language articles,39 primary studies and c.i.ical trials underwent full-text *** resulted in 11 animal,in vitro,and/or human subject journal articles and 8 registered c.i.ical 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-ac.i.ated receptor gamma coac.i.ator-1-alpha(SiRT1/P Gc-1α),SiRT

关键词： hearing loss hypoxia microRNAs oxidative stress sensorineural

Atomistic simulations of plasma catalytic processes

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Frontiers of chemical Science and Engineering 2018年第1期12卷 145-154页

作者： erik c. Neyts Research Group PLASMANT Department of Chemistry University of Antwerp Universiteitsplein 1 2610 Wilrijk-Antwerp Belgium

There is currently a growing interest in the realisation and optimization of hybrid plasma/catalyst systems for a multitude of applications, ranging from nanotechnology to environmental chemistry. in spite of this interest, there is, however, a lack in fundamental understanding of the underlying processes in such systems. While a lot of experimental research is already being carded out to gain this understanding, only recently the first simulations have appeared in the literature. in this contribution, an overview is presented on atomic scale simulations of plasma catalytic processes as carried out in our group. in particular, this contribution focusses on plasma-assisted catalyzed carbon nanostructure growth, and plasma catalysis for greenhouse gas conversion. Attention is paid to what can routinely be done, and where challenges persist.

关键词： atomic scale simulation plasma-catalyst

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.i.flammatory and demyelinating disease of the central nervous system(cNS). Patients with MS experience sensory and motor func.i.n loss due to myelin and/or axon damage perpetuated b... 详细信息

关键词： Hauser sclerosis damage

The role of ions in plasma catalytic carbon nanotube growth： A review

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Frontiers of chemical Science and Engineering 2015年第2期9卷 154-162页

作者： erik c. Neyts Research Group PLASMANT Department of Chemistry University of Antwerp Universiteitsplein 1 2610 Wilrijk-Antwerp Belgium

While it is well-known that the plasma- enhanced catalytic chemical vapor deposition （PEcVD） of carbon nanotubes （cNTs） offers a number of advantages over thermal cVD, the influence of the various individual contributing factors is not well understood. Especially the role of ions is unclear, since ions in plasmas are generally associated with sputtering rather than with growing a material. Even so, various studies have demonstrated the beneficial effects of ion bombardment during the growth of cNTs. This review looks at the role of the ions in plasma- enhanced cNT growth as deduced from both experimental and simulation studies. Specific attention is paid to the beneficial effects of ion bombardment. Based on the available literature, it can be concluded that ions can be either beneficial or detrimental for carbon nanotube growth, depending on the exact conditions and the control over the growth process.

关键词： plasma-enhanced chemical vapor deposition(PEcVD) carbon nanotube (cNT) ion bombardment,defect healing

Special issue on future direc.i.ns in plasma nanoscience

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Frontiers of chemical Science and Engineering 2019年第2期13卷 199-200页

作者： erik c.Neyts Department of chemistry University of Antwerp2610 AntwerpBelgium

Over the past 20 years,plasma nanoscience has become a mature and vibrant *** deals with both the fundamental science and applications of low-temperature plasmas,ion beams,lasers,and related approaches and how this relates to the fabrication,synthesis,modification,and integration in and of nanoscale materials,structures and func.i.nal *** complexity often encountered in research in this field intrinsically calls for both fundamental and applied research,both experimental and *** nanoscience,therefore,is a highly multidisciplinary field,bringing together researchers from physics,chemistry,medicine,engineering,biochemistry,informatics and more.

关键词： Special issue future direc.i.ns plasma nanoscience

S-Adenosyl-L-methionine towards hepatitis c virus expression: Need to consider S-Adenosyl-L-methionine's chemistry, physiology and pharmacokinetics

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World Journal of Gastroenterology 2017年第40期23卷 7343-7346页

作者： Dimitrios Tsikas erik Hanff Alexander Bollenbach core Unit Proteomics Hannover Medical School

S-Adenosyl-L-methionine(SAM) is a cofactor serving as a methyl donor in numerous enzymatic reac.i.ns. it has been reported that SAM has the potential to modify antioxidant-enzymes, glutathione-biosynthesis and methionine adenosyltransferases-1/2 in hepatitis c virus-expressing cells at millimolar concentrations. The efficacy of SAM at micromolar concentrations and the underlying mechanisms remain to be demonstrated.

关键词： S-Adenosyl-L-methionine Bioavailability concentration Liver