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Full-Text Articles in Chemistry

Chemistry And Biochemistry News, Georgia Southern University Aug 2019

Chemistry And Biochemistry News, Georgia Southern University

Biochemistry, Chemistry & Physics: News & Publications (2012-2023)

  • Dr. Carpenter receives COSM Excellence in Teaching Award-2019


Convective Instabilities Derived From Dissipation Of Chemical Energy, Reuben H. Simoyi, Matthew W. Eskew Aug 2019

Convective Instabilities Derived From Dissipation Of Chemical Energy, Reuben H. Simoyi, Matthew W. Eskew

Chemistry Faculty Publications and Presentations

Oxidation reactions of a series of organosulfur compounds by chlorite are excitable, autocatalytic, and exothermic and generate a lateral instability upon being triggered by the autocatalyst. This article reports on the convective instabilities derived from the reaction of chlorite and thiourea in a Hele-Shaw cell. Reagent concentrations used for the development of convective instabilities delivered a temperature jump at the wave front of 2.1 K. The reaction zone was 2 mm and due to normal cooling after the wave front, this induced a spike rather than the standard well-studied front propagation. Localized spatiotemporal patterns develop around the wave front. This …


Sorption Of Copper (Ii), Nickel (Ii) And Cobalt (Ii) Ions Into The Ionite Modified By Polyphinylchloride And Polyethylene Polyamine, Kh Ismoilova, D Bekchanov, Sh Khasanov, M Baltaeva Aug 2019

Sorption Of Copper (Ii), Nickel (Ii) And Cobalt (Ii) Ions Into The Ionite Modified By Polyphinylchloride And Polyethylene Polyamine, Kh Ismoilova, D Bekchanov, Sh Khasanov, M Baltaeva

Scientific journal of the Fergana State University

IPolyphinylchloride was modified by polyethylene polyamine, and the ionites were studied in static conditions by the artificial solution of copper (II), nickel (II) and cobalt (II) ions. In static conditions, factors affecting the sorption process, such as time, temperature and concentration dependence were investigated. The results of the inquiry process were studied by IR analysis


Copolymerization Of Methylacrylate And Acrylic Acid, N Y. Bozorov, V. O. Kudishkin Aug 2019

Copolymerization Of Methylacrylate And Acrylic Acid, N Y. Bozorov, V. O. Kudishkin

Scientific journal of the Fergana State University

Linear copolymers of methylacrylate and acrylic acid with different content of monomer units have been synthesized by classical radical copolymerization in dioxane solution and in the block. The composition of copolymers was determined. The relative activities of the monomers calculated by the methods of Fineman - Ross and Kelen -Tudos. It is shown that the activity of acrylic acid can vary depending on the medium in which copolymerization is carried out.


Defining The Antioxsidants Quantity In Certification Of The Chicken Meat, B. N. Sattarova, I. R. Asqarov, Sh. X. Abdulloev Aug 2019

Defining The Antioxsidants Quantity In Certification Of The Chicken Meat, B. N. Sattarova, I. R. Asqarov, Sh. X. Abdulloev

Scientific journal of the Fergana State University

The article presents an analysis of the results obtained by chromatography-mass-spectrometric studies to determine the mass fractions of certain antioxidants in chicken meat, the excessive amount of which seriously threatens human health. The advantages of this method in the certification of meat products are substantiated. It has been established that the content of alpha-tocopherol in chicken meat imported from some foreign countries is several times higher than that produced in local poultry farms.


Solution Of Cancerogen Asbestos Problems In Obtaining Harmless Fibre Products, M. A. Axmadaliev, I. R. Asqarov Aug 2019

Solution Of Cancerogen Asbestos Problems In Obtaining Harmless Fibre Products, M. A. Axmadaliev, I. R. Asqarov

Scientific journal of the Fergana State University

The article presents the ways of obtaining ecologic harmless composite materials based on mineral fibers in the replacement of asbestos containing goods


Copolymerization Of Methylacrylate And Acrylic Acid, N Y. Bozorov, V. O. Kudishkin Aug 2019

Copolymerization Of Methylacrylate And Acrylic Acid, N Y. Bozorov, V. O. Kudishkin

Scientific journal of the Fergana State University

Linear copolymers of methylacrylate and acrylic acid with different content of monomer units have been synthesized by classical radical copolymerization in dioxane solution and in the block. The composition of copolymers was determined. The relative activities of the monomers calculated by the methods of Fineman - Ross and Kelen -Tudos. It is shown that the activity of acrylic acid can vary depending on the medium in which copolymerization is carried out.


Sorption Of Copper (Ii), Nickel (Ii) And Cobalt (Ii) Ions Into The Ionite Modified By Polyphinylchloride And Polyethylene Polyamine, Kh Ismoilova, D Bekchanov, Sh Khasanov, M Baltaeva Aug 2019

Sorption Of Copper (Ii), Nickel (Ii) And Cobalt (Ii) Ions Into The Ionite Modified By Polyphinylchloride And Polyethylene Polyamine, Kh Ismoilova, D Bekchanov, Sh Khasanov, M Baltaeva

Scientific journal of the Fergana State University

IPolyphinylchloride was modified by polyethylene polyamine, and the ionites were studied in static conditions by the artificial solution of copper (II), nickel (II) and cobalt (II) ions. In static conditions, factors affecting the sorption process, such as time, temperature and concentration dependence were investigated. The results of the inquiry process were studied by IR analysis


Defining The Antioxsidants Quantity In Certification Of The Chicken Meat, B. N. Sattarova, I. R. Asqarov, Sh. X. Abdulloev Aug 2019

Defining The Antioxsidants Quantity In Certification Of The Chicken Meat, B. N. Sattarova, I. R. Asqarov, Sh. X. Abdulloev

Scientific journal of the Fergana State University

The article presents an analysis of the results obtained by chromatography-mass-spectrometric studies to determine the mass fractions of certain antioxidants in chicken meat, the excessive amount of which seriously threatens human health. The advantages of this method in the certification of meat products are substantiated. It has been established that the content of alpha-tocopherol in chicken meat imported from some foreign countries is several times higher than that produced in local poultry farms.


Solution Of Cancerogen Asbestos Problems In Obtaining Harmless Fibre Products, M. A. Axmadaliev, I. R. Asqarov Aug 2019

Solution Of Cancerogen Asbestos Problems In Obtaining Harmless Fibre Products, M. A. Axmadaliev, I. R. Asqarov

Scientific journal of the Fergana State University

The article presents the ways of obtaining ecologic harmless composite materials based on mineral fibers in the replacement of asbestos containing goods


Regulation Of Copper Surface Via Redox Reactions For Enhancing Carbon Dioxide Electroreduction, Bao-Hua Hang, Jin-Tao Zhang Aug 2019

Regulation Of Copper Surface Via Redox Reactions For Enhancing Carbon Dioxide Electroreduction, Bao-Hua Hang, Jin-Tao Zhang

Journal of Electrochemistry

A large-scale application of fossil fuels has led to excessive emission of carbon dioxide (CO2), resulting in serious environmental issues. A promising path to reducing CO2 emissions is recycling CO2 into valuable chemicals and fuels through an electrochemical process. Herein, the redox reactions between copper (Cu) and ferric chloride (FeCl3) have been utilized to regulate the Cu surface composition and structure, aimed to improve the electrocatalytic activity toward CO2 reduction. Typically, a series of samples (named Cu-1h, Cu-2h, Cu-3h and Cu-4h) were prepared via the redox reactions for various time from 1 to …


Single-Layer Oxygen Deficiency Δ-Mno2 For Electrochemical Co2 Reduction, Yue-Feng Zhang, Jian-Jun Liu, Zeng-Xi Wei, Xin-Xin Tian, Jian-Min Ma Aug 2019

Single-Layer Oxygen Deficiency Δ-Mno2 For Electrochemical Co2 Reduction, Yue-Feng Zhang, Jian-Jun Liu, Zeng-Xi Wei, Xin-Xin Tian, Jian-Min Ma

Journal of Electrochemistry

Manganese dioxide (MnO2) has been widely used in catalysis. In addition, since the defect engineering can change the electronic properties of the catalyst, here we have systematically studied electrocatalytic carbon dioxide reduction reaction (CO2RR) on δ-MnO2 with and without oxygen deficiency, denoted as Ov-MnO2 and MnO2, respectively. We calculate the electronic properties and the intermediate of free energy for MnO2 and Ov-MnO2 with the help of spin-polarized density functional theory. By analyzing this result, we can find that the introduction of defects change the δ-MnO2 from semiconducting properties to …


Statuses, Challenges And Strategies In The Development Of Low-Temperature Carbon Dioxide Electroreduction Technology, Xu-Rui Zhang, Xiao-Lin Shao, Jin Yi, Yu-Yu Liu, Jiu-Jun Zhang Aug 2019

Statuses, Challenges And Strategies In The Development Of Low-Temperature Carbon Dioxide Electroreduction Technology, Xu-Rui Zhang, Xiao-Lin Shao, Jin Yi, Yu-Yu Liu, Jiu-Jun Zhang

Journal of Electrochemistry

Low-temperature carbon dioxide (CO2) electrochemical reduction technology is a hotspot for research and development in recent years as a way to reduce the negative impact of CO2 on the environment and to generate energy storage through converting electricity to low-carbon fuels. Although basic research on catalyst activity, product selectivity, and reaction mechanism has been widely reported, the design and practicality of catalytic stability and corresponding electrochemical reactor systems have not been given sufficient attention and systematic development.  In this paper, two important factors affecting the development of CO2 electrochemical reduction technology in low temperature aqueous solution …


Recent Advances In Bismuth-Based Co2 Reduction Electrocatalysts, Rui Zhou, Na Han, Yan-Guang Li Aug 2019

Recent Advances In Bismuth-Based Co2 Reduction Electrocatalysts, Rui Zhou, Na Han, Yan-Guang Li

Journal of Electrochemistry

Carbon dioxide (CO2) is an economical, secure and sustainable carbon resource around us. Its effective capture and recycling have been the focus of our entire society. Using the electrochemical method, CO2 can be reduced to different value-added chemicals or fuels. This approach not only would mitigate CO2 accumulation in the atmosphere, but also would help alleviate our dependence on fossil fuel. In this article, the basic principle and process of electrochemical CO2 reduction are first introduced. The recent development in bismuth-based catalysts for electrocatalytic CO2 reduction is reviewed with an emphasis on their preparation, …


Electrocatalytic Reduction Of Carbon Dioxide To Carbon Monoxide Using Cobalt Nitride, Chen Ma, Peng-Fei Hou, Peng Kang Aug 2019

Electrocatalytic Reduction Of Carbon Dioxide To Carbon Monoxide Using Cobalt Nitride, Chen Ma, Peng-Fei Hou, Peng Kang

Journal of Electrochemistry

Electrocatalytic reduction of carbon dioxide (CO2) is a promising method to alleviate global warming issues, although it still faces many challenges. Herein, we report cobalt nitride for electrocatalytic reduction of CO2 to carbon monoxide (CO) in an aqueous electrolyte. A comparison of catalysts with different preparation temperatures and atmospheres suggests that nitrogen doping is critical to improve catalytic activity. For the most active catalyst of 700-Co5.47N/C, the CO current density reached 9.78 mA·cm-2 at potential of -0.7 V vs. RHE. In addition, the CO/H2 ratio could be adjusted from 1:3 to 3:2 by …


Effect Of Morphology Of Fe-N Codoped Carbon Nanomaterial On Electrochemical Reduction Reactions, Er-Ling Li, Fa Yang, Ming-Bo Ruan, Ping Song, Wei-Lin Xu Aug 2019

Effect Of Morphology Of Fe-N Codoped Carbon Nanomaterial On Electrochemical Reduction Reactions, Er-Ling Li, Fa Yang, Ming-Bo Ruan, Ping Song, Wei-Lin Xu

Journal of Electrochemistry

Graphene nanosheets (GS) and carbon nanotubes have been considered as good catalysts candidates for applications in energy conversion and storage. However, hybrids of GS and carbon nanotubes are always formed in transition metal-based nitrogen-doped system, making the system quite complex for exploring the structure-activity relationship. To prepare the catalysts with desired species controllably, we try to adjust the outcomes with the effect of nitrogen on the growth of carbon nanotubes. In this work, a series of Fe-N co-doped carbon hybrid catalysts containing N-doped GS or hybrids of GS/bamboo carbon nanotubes (BCNTs) or BCNTs were obtained with one-step pyrolyzed method. To …


Electrochemical Detection Of 4-Nitrophenol Based On Glassy Carbon Electrode Modified By Tio2Nps/Rgo Composite, Lin-Na Jiu, Yong-Qiang Cheng Aug 2019

Electrochemical Detection Of 4-Nitrophenol Based On Glassy Carbon Electrode Modified By Tio2Nps/Rgo Composite, Lin-Na Jiu, Yong-Qiang Cheng

Journal of Electrochemistry

4-nitrophenol (4-NP) has become factitious pollution, and presented a serious threat to the nature and human health. It is necessary to develop a convenient and fast detection method. In this work, the glassy carbon electrode modified by titanium dioxide nanoparticles (TiO2NPs)/reduced graphene oxide (RGO) composite as an electrochemical sensor was studied for the trace detection of 4-NP. The morphology of the composite was characterized by scanning electron microscopy (SEM). The homogeneous mixing of titanium dioxide nanoparticles and reduced graphene oxide increased the specific surface area of the composite, and facilitated the electrochemical reaction of 4-NP. The electrochemical characteristics …


Preparations And Electrocatalytic Properties Of Cu-Bipy-Btc-Derived Carbon-Based Catalyst For Oxygen Reduction Reaction, Li-Hua Zhang, Jun-Feng Chen, Wan-Tang Huang, Yong-You Hu, Jian-Hua Cheng, Yuan-Cai Chen Aug 2019

Preparations And Electrocatalytic Properties Of Cu-Bipy-Btc-Derived Carbon-Based Catalyst For Oxygen Reduction Reaction, Li-Hua Zhang, Jun-Feng Chen, Wan-Tang Huang, Yong-You Hu, Jian-Hua Cheng, Yuan-Cai Chen

Journal of Electrochemistry

Efficient and low-cost oxygen reduction reaction (ORR) electrocatalyst plays a key role for fuel cells. In this paper, ORR active metal organic framework (MOF: Cu-bipy-BTC, bipy = 2,2?-bipyridine, BTC = 1,3,5-tricarboxylate) was prepared using hydrothermal method, and then carbon-based material MOF-800 was obtained from pyrolyzing Cu-bipy-BTC at 800 °C. Scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), nitrogen sorption isotherm and X-ray photolectron spectroscopy (XPS) were used to characterize the morphologies and structures of the catalysts. Linear sweep voltammetry (LSV) and current-time curve (i-t) were adopted to evaluate the electrocatalytic properties of the catalysts. The results …


Reaction Induced Morphology Changes Of Tetracene And Pentacene Surfaces, Feifei Li, Jacob W. Ciszek Aug 2019

Reaction Induced Morphology Changes Of Tetracene And Pentacene Surfaces, Feifei Li, Jacob W. Ciszek

Chemistry: Faculty Publications and Other Works

Morphology plays a critical role in determining the properties of solid-state molecular materials, yet fluctuates wildly as these materials undergo reaction. A prototypical system, a vapor–solid Diels–Alder reaction of tetracene and pentacene thin-films, is used to observe the evolution of morphology features as the reaction transitions from surface to bulk. The initial stages of reaction display little topographical change as measured by atomic force microscopy (AFM) and scanning electron microscopy (SEM), and substrates are coated with a uniform layer of product 1–2 molecules thick, as determined by energy-dispersive X-ray (EDX) spectroscopy. The highly textured surfaces of late stage reactions are …


Preface To Special Issue Of Electrochemical Reduction Of Carbon Dioxide, Qing Li, Min Liu Aug 2019

Preface To Special Issue Of Electrochemical Reduction Of Carbon Dioxide, Qing Li, Min Liu

Journal of Electrochemistry

No abstract provided.


Copper-Based Compounds For Electrochemical Reduction Of Carbon Dioxide, Fan Yang, Pei-Lin Deng, You-Jia Han, Pan Jing, Bao-Yu Xia Aug 2019

Copper-Based Compounds For Electrochemical Reduction Of Carbon Dioxide, Fan Yang, Pei-Lin Deng, You-Jia Han, Pan Jing, Bao-Yu Xia

Journal of Electrochemistry

The electrochemical reduction of carbon dioxide (CO2) to useful chemicals and fuels has attracted enormous interest since the deteriorating global warming and energy shortage problems resulted from ever-increasing CO2 emission. Designing efficient catalysts is of capital significance to realize the efficient and selective conversion of CO2. Among various catalysts explored, copper-based compounds have promising potentials with acceptable efficiency for hydrocarbon production. Herein, recent advances on copper-based materials are summarized for electrochemical CO2 conversion. We intend to include the dimensional structure, different forms (alloy, oxide) and molecular catalysts in copper-based catalysts. Moreover, the reaction mechanisms …


Recent Progress In Copper-Based Catalysts For Electrochemical Co2 Reduction, Wen Lei, Wei-Ping Xiao, De-Li Wang Aug 2019

Recent Progress In Copper-Based Catalysts For Electrochemical Co2 Reduction, Wen Lei, Wei-Ping Xiao, De-Li Wang

Journal of Electrochemistry

As the situation of energy crisis and environmental pollution become more and more serious, the electrochemical reduction of carbon dioxide (CO2) has attracted lots of attention because of its multiple meanings such as environment, resources and economic benefits. In this paper, the state of the art electrochemical reduction of CO2 in aqueous solution is reviewed, and the latest research progress in Cu-based catalysts with different structures and morphologies is summarized. In the end, the application prospects, opportunities and challenges of Cu-based materials are briefly presented to provide an outlook for future research directions.


Modifications Of The Cztse/Mo Back-Contact Interface By Plasma Treatments, Wenjin Chen, Teoman Taskesen, David Nowak, Ulf Mikolajczak, Mohamed H. Sayed, Devendra Pareek, Jorg Ohland, Thomas Schnabel, Erik Ahlswede, Dirk Hauschild, Lothar Weinhardt, Clemens Heske, Jurgen Parisi, Levent Gutay Aug 2019

Modifications Of The Cztse/Mo Back-Contact Interface By Plasma Treatments, Wenjin Chen, Teoman Taskesen, David Nowak, Ulf Mikolajczak, Mohamed H. Sayed, Devendra Pareek, Jorg Ohland, Thomas Schnabel, Erik Ahlswede, Dirk Hauschild, Lothar Weinhardt, Clemens Heske, Jurgen Parisi, Levent Gutay

Chemistry and Biochemistry Faculty Research

Molybdenum (Mo) is the most commonly used back-contact material for copper zinc tin selenide (CZTSe)-based thin-film solar cells. For most fabrication methods, an interfacial molybdenum diselenide (MoSe2) layer with an uncontrolled thickness is formed, ranging from a few tens of nm up to ≈1 μm. In order to improve the control of the back-contact interface in CZTSe solar cells, the formation of a MoSe2 layer with a homogeneous and defined thickness is necessary. In this study, we use plasma treatments on the as-grown Mo surface prior to the CZTSe absorber formation, which consists of the deposition of stacked metallic layers …


Dna Recovery From Handwritten Documents Using A Novel Vacuum Technique, Patrick M. Mclaughlin Aug 2019

Dna Recovery From Handwritten Documents Using A Novel Vacuum Technique, Patrick M. Mclaughlin

Student Theses

Investigations of many crimes such as robberies, kidnappings, and terrorism are often associated with the recovery of a paper document which has been written by the perpetrator. Paper can provide a variety of forensic evidence such as DNA, latent fingermarks, and indented writing. The focus of this study was the collection of probative DNA profiles from the text region of a handwritten note through a vacuum suction device without altering or destroying the document. Collection of DNA evidence was carried out in two separate groups. The first group involved 11 volunteers providing a handwritten note sample with unwashed hands. The …


Spectroscopic Description Of The E1 State Of Mo Nitrogenase Based On Mo And Fe X‑Ray Absorption And MöSsbauer Studies, Casey Van Stappen, Roman Davydov, Zhi-Yong Yang, Ruixi Fan, Yisong Guo, Eckhard Bill, Lance C. Seefeldt, Brian M. Hoffman, Serena Debeer Aug 2019

Spectroscopic Description Of The E1 State Of Mo Nitrogenase Based On Mo And Fe X‑Ray Absorption And MöSsbauer Studies, Casey Van Stappen, Roman Davydov, Zhi-Yong Yang, Ruixi Fan, Yisong Guo, Eckhard Bill, Lance C. Seefeldt, Brian M. Hoffman, Serena Debeer

Chemistry and Biochemistry Faculty Publications

Mo nitrogenase (N2ase) utilizes a two-component protein system, the catalytic MoFe and its electron-transfer partner FeP, to reduce atmospheric dinitrogen (N2) to ammonia (NH3). The FeMo cofactor contained in the MoFe protein serves as the catalytic center for this reaction and has long inspired model chemistry oriented toward activating N2. This field of chemistry has relied heavily on the detailed characterization of how Mo N2ase accomplishes this feat. Understanding the reaction mechanism of Mo N2ase itself has presented one of the most challenging problems in bioinorganic chemistry because of the ephemeral nature of its …


Fluorescence Microscopy Of Biophysical Protein Dynamics In Nanoporous Hydrogels, Anuj Saini, Lydia Kisley Aug 2019

Fluorescence Microscopy Of Biophysical Protein Dynamics In Nanoporous Hydrogels, Anuj Saini, Lydia Kisley

Faculty Scholarship

Proteins within nanoporous hydrogels have important biotechnological applications in pharmaceutical purification, tissue engineering, water treatment, biosensors, and medical implants. Yet, oftentimes proteins that are functional in solution lose activity when in contact with soft, nanostructured, condensed phase materials due to perturbations in the folded state, conformation, diffusion, and adsorption dynamics of the protein by the material. Fluorescence microscopy experimentally measures the biophysical dynamics of proteins within hydrogels at the nanoscale and can overcome the limitations of conventional ensemble techniques. An explanation of the benefits of fluorescence is provided, and principles of fluorescence microscope instrumentation and analysis are discussed. Then several …


An Exploration Of Protein And Dna Components In Fingerprint Residue, Ashley Borrego Aug 2019

An Exploration Of Protein And Dna Components In Fingerprint Residue, Ashley Borrego

Student Theses

The main focus of this project was to investigate the protein and DNA components in both sebaceous and eccrine fingerprints. This study investigated the relative content of DNA and proteins in eccrine fingerprints to sebaceous fingerprints. All volunteers were instructed to wash and dry their hands prior to depositing parallel thumbprints. Twenty volunteers were instructed to touch their face to produce sebaceous prints, and 5 volunteers were instructed to wear gloves over a heat source to produce sweaty or eccrine prints. Microscopy was used to score the cellular debris of the right fingerprint on a scale of 1-4 based on …


Modeling Chemical Reactivity In Aqueous And Organic Systems: From Electronic Structure Methods To Force Field Development, Caitlin Gibson Bresnahan Aug 2019

Modeling Chemical Reactivity In Aqueous And Organic Systems: From Electronic Structure Methods To Force Field Development, Caitlin Gibson Bresnahan

LSU Doctoral Dissertations

Modeling reactivity in chemical systems has evolved dramatically in line with the capabilities of modern computing. Despite the advances in computational ability, the level in which one can model a system depends on a number of factors including the region of reactivity, size of the system, level of sophistication required in the molecular description, and so on. Electronic structure methods allow for a detailed description of the potential energy surface and inherently include all essential physics required for reactivity to occur, however these methods are limited by their computational expense. On the other hand, force fields allow for an atomistic …


Our Envirome, Spring/Summer 2019, Issue 40 Aug 2019

Our Envirome, Spring/Summer 2019, Issue 40

Sustain Magazine

No abstract provided.


Plastic Pollution, Fall/Winter 2019, Issue 39.3 Aug 2019

Plastic Pollution, Fall/Winter 2019, Issue 39.3

Sustain Magazine

No abstract provided.