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Journal of Environmental Sciences 2001年第1期13卷 25-36页

作者： b m koroma K X Wang D D Jinya Laboratory of Socioeconomic Science of Food Production Nagoya University Japan.

The GC-Ion Trap mS is recently one of the most efficient instrumental analysis recommended for understanding the chemistry of volatile organic compounds, not only in water but even in the food chain and other environmental media (air and soil). Results of the experiment conducted on water samples from Kuguri and Yatsutani sampling stations showed considerably higher levels of organic enrichment (COD = 10 mg/L and 11 mg/L respectively). Total concentrations of Pb (0.072 mg/L and 0.093 mg/L) and Cd (0.004 mg/L and 0.011 mg/L) on the other hand, invariably exceeded the maximum allowable concentrations for human health and the living environment (Pb = 0.005 mg/L; Cd = 0.001 mg/L respectively). And the toxicity levels for these contaminants at LC50 showed critical impact on rainbow trout (hypersensitive species) at 0.14 mg/L for Pb and 0.007 mg/L for Cd in 96 hours respectively. Although these major contaminants including phenol and 3-, 4-cresol, showed relatively higher toxicity impact in the experimental media, it would remain contentious to justify any associated potential dangers without regular routine water monitoring, at least for a period of one year. Nevertheless, the data could serve as a benchmark through which other phenomena can easily be investigated.

关键词： www Advanced analytical determination of volatile organic compounds and other major contaminants in water samples using GC-Ion Trap mS VOC Eb GC

Effect of Land Reclamation on Nutrient Distribution in Reclaimed Farmlands Overlying Xuzhou Underground Coal mines *1

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Pedosphere 1998年第2期8卷 155-160页

作者： b．m．koroma ZHENGCHUNRONG 等 CollegeofNaturalResourcesandEnvironmentalSciences ZhejiangAgriculturalUniversityHangzhou310029（China

This research was carried out to evaluate the effect of the reclamation procedure with respect to soil fertility and nutrient distribution pattern in the reprecipitated reclaimed soil. Although there was an obvious indication of low levels of essential nutrients in the reclaimed farmlands (organic matter=0.32 g kg -1 ,total N=380.8 mg kg -1 , available P=4.7 mg kg -1 ), compared to the undisturbed farmlands (organic matter=2.5 g kg -1 , total N=1 220 g kg -1 , available P=20.8 mg kg -1 ), the uneven pattern of nutrient distribution was also shown to have been the major limitation to successful reclamation. Further improvement can be achieved through the integration of intensive eco farming systems using proper fertilizer field correction (PFFC) and organic manure for successful reestablishment and management of newly reclaimed farmlands overlying the Xuzhou coal mine subsidence.

关键词： coal mine subsidence hydraulic dredge pump technique land reclamation nutrient distribution

Hetero-interfacial nickel nitride/vanadium oxynitride porous nanosheets as trifunctional electrodes for HER,OER and sodium ion batteries

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Journal of Energy Chemistry 2023年第6期81卷 71-81,I0003页

作者： Tuzhi Xiong Jingting Li Jagadish Chandra Roy malcolm koroma Zhixiao Zhu Hao Yang Lei Zhang Ting Ouyang m.-Sadeeq balogun mohammad Al-mamun College of materials Science and Engineering Hunan Joint International Laboratory of Advanced Materials and Technology for Clean EnergyHunan UniversityChangsha 410082HunanChina Centre for Catalysis and Clean Energy Griffith UniversityGold Coast CampusSouthportQLD 4222Australia College of mechanical and Vehicle Engineering Hunan UniversityChangsha 410082HunanChina Guangxi Key Laboratory of Electrochemical Energy materials School of Chemistry&Chemical EngineeringGuangxi UniversityNanning 530004GuangxiChina Guangxi Key Laboratory of Information materials Guilin University of Electronic TechnologyGuilin 541004GuangxiChina

The development of single electrode with multifunctional purposes for electrochemical devices remains a symbolic challenge in recent *** work explores interfacially-rich transition metal nitride hybrid that consist of nickel nitride and vanadium oxynitride(VO_(0.26)N_(0.52))on robust carbon fiber(denoted CF/Ni_(3)N/VON)as trifunctional electrode for hydrogen evolution reaction(HER),oxygen evolution reaction(OER),and sodium ion batteries(SIbs).The as-prepared CF/Ni_(3)N/VON exhibits low HER overpotential of 48 m V@10 m A cm^(-2),OER overpotential of 287 m V@10 m A cm^(-2),and sodium-ion anode storage reversible capacity of 555 m A h g^(-1)@0.2 *** analyses reveal that the Ni_(3)N effectively facilitates hydrogen desorption for HER,increases the electrical conductivity for OER,and promotes the Na-ion storage intercalation process,while the VON substantially elevates the water dissociation kinetics for HER,accelerates the adsorption of OH*intermediate for OER and enhances the Na-ion surface adsorption storage *** to the excellent HER and OER performances of the CF/Ni_(3)N/VON electrode,an overall water splitting device denoted as CF/Ni_(3)N/VON//CF/Ni_(3)N/VON was not only assembled showing an operating voltage of 1.63 V at current density of 10 m A cm^(-2)but was also successfully self-powered by the assembled CF/Ni_(3)N/VON//CF/Na_(3)V_(2)(PO_(4))_(3) flexible sodium ion *** work will contribute to the development of efficient and cost-effective flexible integrated electrochemical energy devices.

关键词： Interstitial nitride Trifunctional electrode Heterointerface Alkaline water splitting Sodium ion battery

mitochondria–cGAS–STING axis is a potential therapeutic target for senescence-dependent inflammaging-associated neurodegeneration

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Neural Regeneration Research 2025年第3期20卷 805-807页

作者： Josém.Izquierdo Centro de biología molecular Severo Ochoa(Cbm) Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid(CSIC-UAM)MadridSpain

The word “senescence” comes from the Latin senescens, meaning “to begin to age”, and is characterized by a long-lasting but reversible block in proliferation, resulting from stress-induced cell cycle arrest of pre... 详细信息

关键词： Latin potential lasting

Water Pollution Laws in Sierra Leone—A Review with Examples from the UK and USA

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Natural Resources 2018年第11期9卷 361-388页

作者： Abubakarr S. mansaray Jason Aamodt bashiru m. koroma Oklahoma Water Resources Center Department of Plant and Soil Science Oklahoma State University 139 Agricultural Hall Stillwater Oklahoma USA Spears College of business Oklahoma State University Stillwater Oklahoma USA School of Postgraduate Studies Njala University Njala Campus Freetown Sierra Leone

In Sierra Leone, poor water quality is a major threat to public health and aquatic life. The main source of this problem appears to be poorly?regulated waste disposal. Even though water pollution laws exist, their enforcement is challenged by many gaps and,?seemingly, they?focus on the quest to sustain natural resource exploitation. This work presents a case for?strengthening?such laws to promote public health, economic growth, and resource conservation. The article presents examples of problems that necessitated promulgation of water pollution laws in the US and the UK. Sierra Leone has been affected by similar problems such as public health, war efforts, and industrialization.

关键词： Water Pollution Permit Public Health Agriculture mining

Investigation into the Impacts of Artisanal Gold mining on the Livelihood Foundation of baomahun Community in Southern Sierra Leone

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Natural Resources 2018年第2期9卷 42-54页

作者： Ishmail Sheriff Alhaji brima Gogra bashiru m. koroma Institute of Environmental management and Quality Control School of Environmental Sciences Njala University Freetown Sierra Leone Chemistry Department School of Environmental Sciences Njala University Freetown Sierra Leone

Artisanal gold mining has a long history in Sierra Leone. mining is the most important economic activity in the communities endowed with minerals. many people who are often disadvantaged in the labour market are engaged in this sector. The poor implementation of mining laws and regulations is fueling the rate of involvement in the sector. In-depth studies of the effect of artisanal mining activities on the livelihood strategy of non-miming population in Sierra Leone are rare. The overarching objective of this work is to bring to light the effect of artisanal gold mining on the environment and livelihood of local resident with a case study of baomahun, Delenga Section of Valunia Chiefdom, bo District, Southern Sierra Leone. The study population comprised of people residing at the study area as at 2015. The primary sampling units included elements from the baomahun vicinity such as miners, mines monitors, conservation agents and local residents of the village. The sample frame employed in this study was the random selection of artisanal miners at each site where mining was being undertaken, mines monitoring officers, conservation agents and local residents. Sample size was 76 people. This was done to indicate proper representation of the study area. And also 76 questionnaires were administered to miners, mines monitors, conservation agents and local residents. both primary data and secondary data were used in the study. Detailed explanation of the analyses was accomplished by both qualitative and quantitative methods. The study revealed that there are varied degrees of visible impacts of artisanal mining on the environments. They include soil depression;creation of water pools in abandoned unfilled mines and diversion, and turbidity of local streams. Artisanal mining as an economic activity has imparted both positively and negatively on the livelihood of resident. Significant gaps and disparities exist in the implementation of the current mines and minerals Act of 200

关键词： Artisanal mining Livelihood Foundation baomahun Questionnaire Environment

On a biseparability criterion of bipartite qudit state

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Chinese Physics b 2019年第8期28卷 42-49页

作者： b benzimoun m Daoud LPHE-modeling and Simulation Faculty of SciencesUniversity Mohammed ⅤRabatMorocco Department of Physics Faculty of Sciences-Ain ChockUniversity Hassan ⅡCasablancaMorocco Abdus Salam International Centre for Theoretical Physics TriesteItaly

In this paper,we propose a new approach to tackle the separability problem for bipartite qudit *** is based on the majorana representation which allows to represent a N-spinors(qudit)as a symmetric state of N spin-1/*** also discuss how we can exploit such representation and the notion of the biseparability of multipartite qubit states in the sense to establish new criteria of the separability problem based on the PPT and concurrence.

关键词： separability bipartite qubit state partial separability majorana representation

Phase diagrams and magnetic properties of the mixed spin-1 and spin-3/2 Ising ferromagnetic thin film: monte Carlo treatment

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Chinese Physics b 2019年第2期28卷 414-419页

作者： b boughazi m boughrara m Kerouad Laboratoire Physique des matériaux et modélisation des Systémes(LP2mS) UnitéAssociée au CNRST-URAC:08Faculty of SciencesUniversity Moulay Ismail

Phase diagrams and magnetic properties of the mixed spin-1 and spin-3/2 Ising film with different single-ion anisotropies are investigated, by the use of monte Carlo simulation based on heat bath algorithms. The effects of the crystal-fields and the surface coupling on the phase diagrams are investigated in detail and the obtained phase diagrams are presented. Depending on the Hamiltonian parameters, the system exhibits both second-and first-order phase transitions besides tricritical point, triple point, and isolated critical end point.

关键词： monte Carlo simulation thin film phase diagrams magnetic properties

Quality Assessment of Five (5) brands of Sachet Water marketed in bo City

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Natural Resources 2018年第4期9卷 110-128页

作者： Solomon K. bona Alhaji brima Gogra bashiru m. bashiru m. koroma Chemistry Department School of Environmental Sciences Njala University Freetown Sierra Leone

This study covers some physical, chemical, and bacteriological parameters needed to be tested for drinking water quality. The purpose of the research is to assess and compare the quality of five different brands of sachet water marketed in bo city and to give relevant recommendation(s) were possible. The results obtained were compared to the standard set for each parameter by the World Health Organization (WHO) and the maximum contaminant level set by the United State Environment Protection Agency (USEPA). Five brands of sachets water were selected in bo city and their physical and chemical parameters were evaluated in the Njala University Quality Control Laboratory (NUQCL), and their bacteriological evaluation was done in the Sierra Rutile laboratory. The physical parameters tested for were in accordance with the standards set by the WHO with the exception of the temperatures for each brand which were above the WHO standard. The pH of all the sachets water was in the acidic range, below the standard range and the maximum contaminant level set by the WHO and USEPA respectively. This affected the alkalinity of all the sachets water to be zero (0). None of the sachets water completely met the WHO standard and the USEPA maximum contaminant level for all the parameters tested for in this research. In this regard, none of the sachets water is completely recommended for drinking.

关键词： bacteriological bo city maximum contaminant level physical and chemical parameters. sachet water water quality

Strong and ductile mg alloys developed by dislocation engineering

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Journal of materials Science & Technology 2019年第3期35卷 394-395页

作者： m.Wang b.b.He m.X.Huang Department of mechanical Engineering The University of Hong Kong Shenzhen Institute of Research and Innovation The University of Hong Kong

Dislocation engineering concept has been successfully employed to tackle the strength-ductility trade-off in steels, resulting in the development of high-strength high-ductility deformed and partitioned(D&P)steel. The present perspective proposes to employ such dislocation engineering concept to develop strong and ductile magnesium(mg) alloys. High density of dislocations could be generated at appropriate temperature and retained in the mg alloy after quenching to room temperature. Those dislocations inherited from the warm deformation could provide dislocation sources when the mg alloy is deformed at room temperature, resulting in good ductility. The high dislocation density generated at warm deformation provides dislocation forest hardening, leading to improved yield strength of mg alloy.

关键词： Dislocation engineering mg alloys Warm rolling Strength and ductility