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1.
Polymers (Basel) ; 13(4)2021 Feb 21.
Article in English | MEDLINE | ID: mdl-33670084

ABSTRACT

Our society's most pressing challenges, like high CO2 emission and the constant battle against energy poverty, require a clean and easier solution to store and utilize the renewable energy resources. However, recent electrochemical components are expensive and harmful to the environment, which restricts their widespread deployment. This study proposes an easy method to synthesize and fabricate composite membranes with abundantly found biomass lignin polymer to replace conventional costly and toxic electrode materials. Easier manipulation of lignin within the polymeric matrix could provide the improved composite to enhance its electrochemical activity. Our major focus is to activate the quinone moiety via oxidation in the polymeric mixture using a strong ionic acid. The physico-chemical and electrochemical characterizations of two different lignins within varied polymeric mixture compositions have been carried out to confirm that the redox properties of pure unmodified lignin could be achieved via intrinsic mutual sharing of the structural properties and intercross linkage leading to improved integrity and redox activity/conductivity.

2.
RSC Adv ; 11(38): 23644-23653, 2021 Jul 01.
Article in English | MEDLINE | ID: mdl-35479805

ABSTRACT

Lignin, an aromatic polymer, offers interesting electroactive redox properties and abundant active functional groups. Due to its quinone functionality, it fulfils the requirement of erratic electrical energy storage by only providing adequate charge density. Research on the use of lignin as a renewable material in energy storage applications has been published in the form of reviews and scientific articles. Lignin has been used as a binder, polymer electrolyte and an electrode material, i.e. organic composite electrodes/hybrid lignin-polymer combination in different battery systems depending on the principal charge of quinone and hydroquinone. Furthermore, lignin-derived carbons have gained much popularity. The aim of this review is to depict the meticulous follow-ups of the vital challenges and progress linked to lignin usage in different lithium-based conventional and next-generation batteries as a valuable, ecological and low-cost material. The key factor of this new finding is to open a new path towards sustainable and renewable future lithium-based batteries for practical/industrial applications.

3.
ChemSusChem ; 9(22): 3206-3212, 2016 11 23.
Article in English | MEDLINE | ID: mdl-27796086

ABSTRACT

Two new cathode materials based on redox organosulfur polymers were synthesized and investigated for rechargeable lithium batteries as a proof-of-concept study. These cathodes offered good cycling performance owing to the absence of polysulfide solubility, which plagues Li/S systems. Herein, an aliphatic polyamine or a conjugated polyazomethine was used as the base to tether the redox-active species. The activity comes from the cleavage and formation of S-S or N-S bonds, which is made possible by the rigid conjugated backbone. The synthesized polymers were characterized through FTIR spectroscopy and thermogravimetric analysis (TGA). Galvanostatic measurements were performed to evaluate the discharge/charge cycles and characterize the performance of the lithium-based cells, which displayed initial discharge capacities of approximately 300 mA h g-1 at C/5 over 100 cycles with approximately 98 % Coulombic efficiency.


Subject(s)
Polymers/chemistry , Sulfur/chemistry , Electrochemistry , Electrodes , Kinetics , Oxidation-Reduction
4.
World J Gastroenterol ; 16(5): 603-7, 2010 Feb 07.
Article in English | MEDLINE | ID: mdl-20128029

ABSTRACT

AIM: To investigate the similarities and dissimilarities in patients with hepatitis B and hepatitis C, clinically and metabolically. METHODS: Fifty patients with hepatitis B virus and hepatitis C virus infection were included in this study, along with fifty healthy controls for comparison purposes. Intravenous blood (10 mL) samples from patients and healthy subjects were collected and made to clot before serum was separated and immediately levels of the enzymes, alkaline phosphatase (ALK), creatinine phosphokinase (CPK), lactate dehydrogenase (LDH), serum glutamate oxaloacetate transaminase (s-GOT) and serum glutamate pyruvate transaminase (s-GPT) were determined by a kit method. For total content of each metal the serum samples were analyzed using atomic absorption spectrophotometry. Levels of cholesterol, triglycerides, urea, creatinine and uric acid were determined using a kit method on Microlab 300. RESULTS: Serum magnesium and copper levels remained unchanged, whereas the concentration of zinc decreased and iron increased significantly in both groups of patients. Total antioxidant activity was significantly decreased in both hepatitis B and C. Among the enzymes analyzed, ALK, s-GPT, LDH and s-GOT were all significantly increased in both patients with hepatitis B and C whereas CPK was significantly decreased in patients with hepatitis B and remained unchanged in patients with hepatitis C. CONCLUSION: The information accumulated by this study will help provide a better understanding of involved metabolic processes in order to design appropriate therapeutic approaches for treating these patients, so they can recover and lead normal lives.


Subject(s)
Hepatitis B/metabolism , Hepatitis C/metabolism , Liver/metabolism , Adult , Alkaline Phosphatase/blood , Aspartate Aminotransferases/blood , Blood Chemical Analysis , Copper/blood , Creatine Kinase/blood , Female , Hepacivirus/metabolism , Hepatitis B Surface Antigens/blood , Hepatitis B virus/metabolism , Humans , Iron/blood , L-Lactate Dehydrogenase/blood , Male , Manganese/blood , Middle Aged , Zinc/blood
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