Investigation Of Heavy Metal Composition And Associated Health Risks From Selected Groundwater Wells In Temeke, Dar-Es-Salaam,
2024
University of Dar es salaam
Investigation Of Heavy Metal Composition And Associated Health Risks From Selected Groundwater Wells In Temeke, Dar-Es-Salaam, Justin M. Jeremiah
Tanzania Journal of Engineering and Technology (TJET)
Water quality continues to be the challenge to residents in Dar es Salaam due to various anthropogenic activities in the city. This study was conducted to assess groundwater quality by determining concentrations of heavy metals. Both probability and Nonprobability sampling techniques were used to collect samples from 40 groundwater wells in 24 wards of Temeke municipal and analysed using Microwave Plasma Atomic Emission Spectrometer (Agilent 4210 MP-AES) at the Geochemistry Laboratory of the University of Dar es Salaam. Results indicated varying heavy metal concentrations ranging from 0.71 ± 0.08 to 6.64 ± 0.21 mg/l for As, 0.02 ± 0.01 to …
Professor Yong Yang, The Editorial Board Member Of Journal Of Electrochemistry, Is Elected As A Fellow Of The Electrochemical Society,
2024
Chinese Chemical Society | Xiamen University
Professor Yong Yang, The Editorial Board Member Of Journal Of Electrochemistry, Is Elected As A Fellow Of The Electrochemical Society, Editorial Office Of J.Electrochem.
Journal of Electrochemistry
No abstract provided.
First Announcement Of 76th Annual Meeting Of The International Society Of Electrochemistry,
2024
Chinese Chemical Society | Xiamen University
First Announcement Of 76th Annual Meeting Of The International Society Of Electrochemistry, International Society Of Electrochemistry (Ise)
Journal of Electrochemistry
No abstract provided.
Series Reports From Professor Wei’S Group Of Chongqing University: Advancements In Electrochemical Energy Conversions (1/4): Report 1: High-Performance Oxygen Reduction Catalysts For Fuel Cells,
2024
State Key Laboratory of Advanced Chemical Power Sources (Chongqing University); College of Chemistry and Chemical Engineering, Chongqing University, Chongqing, 400044, China
Series Reports From Professor Wei’S Group Of Chongqing University: Advancements In Electrochemical Energy Conversions (1/4): Report 1: High-Performance Oxygen Reduction Catalysts For Fuel Cells, Fa-Dong Chen, Zhuo-Yang Xie, Meng-Ting Li, Si-Guo Chen, Wei Ding, Li Li, Jing Li, Zi-Dong Wei
Journal of Electrochemistry
Two major challenges, high cost and short lifespan, have been hindering the commercialization process of low-temperature fuel cells. Professor Wei’s group has been focusing on decreasing cathode Pt loadings without losses of activity and durability, and their research advances in this area over the past three decades are briefly reviewed herein. Regarding the Pt-based catalysts and the low Pt usage, they have firstly tried to clarify the degradation mechanism of Pt/C catalysts, and then demonstrated that the activity and stability could be improved by three strategies: regulating the nanostructures of the active sites, enhancing the effects of support materials, and …
Kai Wu, The Editorial Board Member Of Journal Of Electrochemistry And Chief Scientist Of Catl, Receives The National Science And Technology Progress Award,
2024
Chinese Chemical Society | Xiamen University
Kai Wu, The Editorial Board Member Of Journal Of Electrochemistry And Chief Scientist Of Catl, Receives The National Science And Technology Progress Award, Editorial Office Of J.Electrochem.
Journal of Electrochemistry
No abstract provided.
Sorbitol-Electrolyte-Additive Based Reversible Zinc Electrochemistry,
2024
Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education), Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Renewable Energy Conversion and Storage Center (RECAST), College of Chemistry, Nankai University, Tianjin, 300071, China
Sorbitol-Electrolyte-Additive Based Reversible Zinc Electrochemistry, Qiong Sun, Hai-Hui Du, Tian-Jiang Sun, Dian-Tao Li, Min Cheng, Jing Liang, Hai-Xia Li, Zhan-Liang Tao
Journal of Electrochemistry
The unstable zinc (Zn)/electrolyte interfaces formed by undesired dendrites and parasitic side reactions greatly hinder the development of aqueous zinc ion batteries. Herein, the hydroxy-rich sorbitol was used as an additive to reshape the solvation structure and modulate the interface chemistry. The strong interactions among sorbitol and both water molecules and Zn electrode can reduce the free water activity, optimize the solvation shell of water and Zn2+ ions, and regulate the formation of local water (H2O)-poor environment on the surface of Zn electrode, which effectively inhibit the decomposition of water molecules, and thus, achieve the thermodynamically stable …
Optoelectronic And Morphological Surface Resistance Evaluation Of Laser-Induced Graphene Counter Electrodes For Potential Applications In Cesium Lead Halide Perovskite Solar Cells, Ziad Khalifa, Sameh Osama Abdellatif, Rami Ghannam
Chemical Engineering
This study investigates the physicochemical, optical, and electrical characterization of laser-induced graphene (LIG) samples for integration as counter electrodes in cesium lead halide perovskite solar cells. The impact of laser processing parameters on electrode performance is explored, including laser power, laser speed, and beam defocus. Density functional theory (DFT) computational modeling is employed for atomistic investigation and work function estimation, demonstrating the density of states (DOS), quantum capacitance of the graphene sheets, and energy work function. NiO is utilized as a hole transport layer, and the energy work function of LIG is tuned accordingly. SEM measurements estimate thin film porosity, …
Response To Replication Stress And Maintenance Of Genome Stability By Wrn, The Werner Syndrome Protein,
2024
University of Kentucky
Response To Replication Stress And Maintenance Of Genome Stability By Wrn, The Werner Syndrome Protein, David K. Orren, Amrita Machwe
Markey Cancer Center Faculty Publications
Werner syndrome (WS) is an autosomal recessive disease caused by loss of function of WRN. WS is a segmental progeroid disease and shows early onset or increased frequency of many characteristics of normal aging. WRN possesses helicase, annealing, strand exchange, and exonuclease activities and acts on a variety of DNA substrates, even complex replication and re- combination intermediates. Here, we review the genetics, biochemistry, and probably physiological functions of the WRN protein. Although its precise role is unclear, evidence suggests WRN plays a role in pathways that respond to replication stress and maintain genome stability particularly in telomeric regions.
Preparation Of Β-Ni (Oh)2 Nanosheet–Modified Glassy Carbon For Pseudocapacitors,
2024
Department of Chemistry, Faculty of Mathematics and Natural Sciences, Universitas Indonesia, Depok 16424, Indonesia
Preparation Of Β-Ni (Oh)2 Nanosheet–Modified Glassy Carbon For Pseudocapacitors, Muhammad Buchari Setia Putra, Aliyah Aliyah, Afiten Rahmin Sanjaya, Respati Kevin Pramadewandaru, Hoeil Chung, Tribidasari Anggraningrum Ivandini
Makara Journal of Science
β-Nickel hydroxide (Ni(OH)2) nanosheet–modified glassy carbon for pseudocapacitors was successfully prepared. The nanosheets were synthesized via a conventional growth seeding method combined with hydrothermal treatment. Transmission electron microscopy (TEM) characterization indicated the hexagonal structure of the nanosheets of around 15 nm in size, and X-ray diffraction (XRD) pattern confirmed the β-phase lattice crystal. These nanosheets used to modify the glassy carbon surface, increased the electroactive surface area by around 15 times. Furthermore, electrochemical investigation of the modified glassy carbon revealed an excellent performance and a specific capacitance of 628.01 F g−1 at a 1 A g−1 …
Activity Descriptors As Tools For Designing Highly Efficient Electrocatalysts For Water Splitting,
2024
American University in Cairo
Activity Descriptors As Tools For Designing Highly Efficient Electrocatalysts For Water Splitting, Aya Gomaa
Theses and Dissertations
There is an uprising urge to design efficient, active, and durable catalysts to achieve sustainable hydrogen production. The unambiguity of which material should be used pushed the scientific community to devote enormous efforts in exploring different elements with different ratios on trial and error bases. However, the bridge between the theoretical calculation and the experiments introduced a new realm of designing efficient catalysts by introducing the concept of activity descriptors. In the first part of the thesis, the ability to convert waste stainless steel (SS) 316L meshes into highly efficient and durable oxygen evolution reaction (OER) catalysts is demonstrated. The …
Electrochemical Nitrate Reduction To Ammonia On Cu Based Nanoparticles Using Quantum Mechanical Simulations,
2024
New Jersey Institute of Technology
Electrochemical Nitrate Reduction To Ammonia On Cu Based Nanoparticles Using Quantum Mechanical Simulations, Kathan Bhavin Shukla
Theses
Nitrate reduction to ammonia (NRA) is critical for environmental remediation and energy conservation, as it can remove harmful nitrate (NO3-) from water sources while producing usable ammonia (NH3). Cu represents one of the most promising non-noble-metal NRA electrocatalysts. However, the intrinsic catalytic activity of Cu facets and their influence under different pH conditions remain unclear, particularly in the presence of ions commonly found in wastewater such as Cl-, Na+, Mg2+, and Ca2+. Using density functional theory (DFT) calculations, we evaluated the nitrate reduction to ammonia (NRA) pathways …
Recent Advance In Electrochemical Dehalogenative Deuteration,
2024
State Key Laboratory and Institute of Elemento-Organic Chemistry, Frontiers Science Center for New Organic Matter, College of Chemistry, Nankai University, Tianjin, 300071, China
Recent Advance In Electrochemical Dehalogenative Deuteration, Peng-Fei Li, Guang-Sheng Kou, Li-Ping Qi, You-Ai Qiu
Journal of Electrochemistry
In recent years, the incorporation of deuterium atoms into organic compounds has emerged as a vital focus in the development of pharmaceutical molecules. This trend is driven by the increasing recognition of the significance of compounds containing deuterium atoms across various domains, including materials and biopharmaceuticals, where they have found widespread applications in mechanistic studies within the realms of chemistry and biology. Meanwhile, organic electrochemistry, as a relatively environmentally friendly catalytic mode with broad adaptability to redox reactions, has emerged as a crucial alternative to traditional halogen-deuterium exchange in the context of the reduction deuteration of halides. This approach circumvents …
Comparison Of Ligands In Palladium-Catalyzed Electrochemical Allyl 4-Pyridinylation,
2024
a Department of Material Science and Technology, Taizhou University, Taizhou 318000, Zhejiang, China; b School of Chemistry and Chemical Engineering Nanjing University, Nanjing 210023, Jiangsu, China
Comparison Of Ligands In Palladium-Catalyzed Electrochemical Allyl 4-Pyridinylation, Wei-Jie Ding, Chun-Hui Yang, Zhong-Tao Feng, Shi-Rong Lu, Xu Cheng
Journal of Electrochemistry
4-CN-pyridine is a widely applied 4-pyridinylation reagent for diverse transformations. Conventionally, the reaction proceeds via an open-shell radical cross-coupling pathway. Following our previous study, in this work, we report the Pd-catalyzed allyl 4-pyrinylation reaction under electrochemical conditions. The reaction proceeds via radical-polar crossover pathway in which the role of phosphine ligand in reactivity and selectivity was extensively investigated.
Nickel-Catalyzed Α-Arylation Of Α-Cyanoacetates Enabled By Electrochemistry,
2024
State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai 200032, China
Nickel-Catalyzed Α-Arylation Of Α-Cyanoacetates Enabled By Electrochemistry, Zi-Meng Li, Zhang-Jian Li, Anat Milo, Ping Fang, Tian-Sheng Mei
Journal of Electrochemistry
β-Amino acids have a wide range of applications in the field of pharmaceuticals. Utilizing a combination strategy of nickel catalysis and paired electrolysis, a catalytic α-arylation protocol of carbonyl compounds has been developed. This protocol affords various a-aryl-a-cyanoacetates, which can be reduced to high-value-added α-aryl-β-amino acids. The cross-coupling reaction of electron-deficient aryl bromides with a-cyanoacetates achieves the expected products with good yields and functional group compatibility under mild conditions. Excessive electron-richness in initial aryl bromides facilitates the self-coupling of desired products. DFT calculations confirm that the presence of electron-rich aryl substitutions decreases the reduction potentials of the product anions, making …
A Comprehensive Review Of Fischer-Tropsch Synthesis Processes To Produce Sustainable Diesel And Aviation Fuel,
2024
Georgia Southern University
A Comprehensive Review Of Fischer-Tropsch Synthesis Processes To Produce Sustainable Diesel And Aviation Fuel, Joseph C. Steinagel
Honors College Theses
The greatest threat known to humankind today is global warming. It affects every nation on the planet and the natural order of all living things. Consequently, this ongoing crisis necessitates action to scientifically revolutionize important areas of society, including researching modern adaptations of the transportation industry. In that regard, it has been determined that an effective short-term answer to eliminating carbon emissions is to produce sustainable fuels that run cooperatively with the well-established machines of today. Sustainable aviation fuel (SAF) is one such topic of interest, and the Fischer-Tropsch synthesis process is an effective way of producing SAF. To that …
Ionic Conductivity, Li+ Transference Number, And Diffusion Coefficient Of A Solid-State Electrolyte Composite,
2024
Brigham Young University
Ionic Conductivity, Li+ Transference Number, And Diffusion Coefficient Of A Solid-State Electrolyte Composite, Lizbeth Zurita
Reviews, Analyses, and Instructional Studies in Electrochemistry (RAISE)
The design of solid-state electrolyte (SSE) composites involves the fundamental study of transport properties, such as ionic conductivity. This transport property is influenced by the transport mechanisms of the charge species inside the composite, such as diffusion and migration. In this work, we perform the measurement of these three parameters through defined techniques. The resulting parameters were: ionic conductivity, the diffusion coefficient, and the Li+ transference number.
An Overview Of How To Measure The Kinetic Properties Of An Anode Material For The Chlorine Evolution Reaction,
2024
Brigham Young University
An Overview Of How To Measure The Kinetic Properties Of An Anode Material For The Chlorine Evolution Reaction, Cameron Vann
Reviews, Analyses, and Instructional Studies in Electrochemistry (RAISE)
The process of generating chlorine gas using electrolysis in aqueous systems is well established. However, a new process requires chlorine to be generated at high temperatures using molten salt. This harsh environment requires a new study of anode materials for the chlorine evolution reaction. Anode materials can be compared by their kinetic parameters, the transfer coefficient α and the exchange current i0. The basic theory of these properties as they relate to the chlorine evolution reaction has been detailed and an analysis method for finding these effective parameters has been shown and demonstrated.
Synthesis Of Acetylene Diols With The Participation Of The Bu4noh/Dmso/H2o Catalytic Systems,
2024
Chirchik State Pedagogical University, Chirchik, Uzbekistan
Synthesis Of Acetylene Diols With The Participation Of The Bu4noh/Dmso/H2o Catalytic Systems, Muyassar K. Salieva, Odiljon E. Ziyadullayev, Guzal K. Otamukhamedova, Rifkat F. Talipov, Lochin K. Ablakulov
CHEMISTRY AND CHEMICAL ENGINEERING
The purpose of this work in this study, acetylene alcohols containing heteroatomic substituents in their molecular composition- 2-(-thiophen-2-yl)but-3-yn-2-ol, 2-(3-methylthiophen-2-yl)but-3-yn-2-ol, 2-(furan-2-yl)but-3yn-2-ol, 2-(pyridin-4-yl)but-3-yn-2-ol, 2-(5-chlorothiophen-2-yl)but-3-yn-2-ol, 2-(5-bromothiophen-2yl)but-3-yn-2-ol acetylene diols were synthesized based on the reaction with acetone in a dimethyl sulfoxide solvent in the presence of the Bu4NOH/DMSO/H2O catalytic system. The influence of the molar ratio of starting materials, reaction duration, temperature, nature of the catalyst and solvents on the product yield was systematically studied. The composition, purity and structure of the new generation of synthesized acetylenediols have been confirmed by modern physicochemical methods. The mechanism of the reaction process …
Synthesis Of High Molecular Mass Resins Based On Furfuryl Alcohol,
2024
Tashkent Institute of Chemical Technology, Tashkent, Uzbekistan
Synthesis Of High Molecular Mass Resins Based On Furfuryl Alcohol, Boysayid U. Sayidov, Latif E. Jumanov, Muzaffar G. Alimukhamedov, Sherali A. Umarov, Farhod A. Magrupov
CHEMISTRY AND CHEMICAL ENGINEERING
The purpose of the work is to study the process of synthesis of furfuryl oligomers with high molecular weight at various ratios of furfuryl alcohol and hydroxyl-containing polyether polyol. The influence of the process method on the yield of high-molecular furfuryl oligomer is shown - with a one-step synthesis method with an increase in the amount of furfuryl alcohol from 20 to 50 moles per 1 mole of polyether polyol, the yield of the final product decreases from 75% to 56%, apparently due to high exothermic effects, causing gelation systems. In contrast to the one-time introduction of the catalyst, its …
Synthesis And Technology Of Vinyl Esters Of Aromatic Carboxylic Acids Based On Vinyl Acetate,
2024
National University of Uzbekistan, Tashkent, Uzbekistan
Synthesis And Technology Of Vinyl Esters Of Aromatic Carboxylic Acids Based On Vinyl Acetate, Askar B. Parmanov, Suvonkul E. Nurmanov, Saida S. Abdurakhmanova, Sarvinoz I. Tirkasheva, Begzod F. Adashev
CHEMISTRY AND CHEMICAL ENGINEERING
In this work the vinylation reactions of aromatic carboxylic acids with vinyl acetate, which contain various substituents, in the presence of 2-chloro-4,6-dimethoxy-1,3,5-triazine were studied for the first time. The influence of the nature of the starting materials, temperature, reaction duration, solvent and reagents - zinc triflate (Zn(OTf)2, 3,3-diphenylbinaphthol (3,3'-Ph2BINOL-2Li), tertiary potassium butylate (KOtrBu), butyllithium (BuLi) for the synthesis of vinyl esters. The synthesis of vinyl esters of aromatic carboxylic acids was carried out: benzoiс, 2-phenylacetic, 4-methylbenzoic, 4-methoxybenzoic, 3,4-dimethoxybenzoic, 2-brombenzoic, 4-brombenzoic, 4-fluorobenzoic, 3-nitrobenzoic, 4-nitrobenzoic, 4-tertiary butylbenzoic, 2-chlorobenzoic, 4-chlorobenzoic, 3-hydroxybenzoic and 4-hydroxybenzoic acids has been studied. …
