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Oxidative stress and diabetes: antioxidative strategies

Pengju Zhang, Tao Li, Xingyun Wu, Edouard C. Nice, Canhua Huang, Yuanyuan Zhang

《医学前沿（英文）》 2020年第14卷第5期页码 583-600 doi: 10.1007/s11684-019-0729-1

摘要： Diabetes mellitus is one of the major public health problems worldwide. Considerable recent evidence suggests that the cellular reduction–oxidation (redox) imbalance leads to oxidative stress and subsequent occurrence and development of diabetes and related complications by regulating certain signaling pathways involved in β-cell dysfunction and insulin resistance. Reactive oxide species (ROS) can also directly oxidize certain proteins (defined as redox modification) involved in the diabetes process. There are a number of potential problems in the clinical application of antioxidant therapies including poor solubility, storage instability and non-selectivity of antioxidants. Novel antioxidant delivery systems may overcome pharmacokinetic and stability problem and improve the selectivity of scavenging ROS. We have therefore focused on the role of oxidative stress and antioxidative therapies in the pathogenesis of diabetes mellitus. Precise therapeutic interventions against ROS and downstream targets are now possible and provide important new insights into the treatment of diabetes.

关键词： diabetes oxidative stress redox modification antioxidative therapy novel antioxidant delivery

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Probing the redox process of

Rui Lu, Wei Chen, Wen-Wei Li, Guo-Ping Sheng, Lian-Jun Wang, Han-Qing Yu

《环境科学与工程前沿（英文）》 2017年第11卷第1期 doi: 10.1007/s11783-017-0905-y

摘要： Fluorescece spectroelectrochemistry is used to probe redox process of benzoquinone. The benzoquinone reduction state has a lower fluorescence quantum efficiency. CVF and DCVF can reveal more information about benzoquinone redox reactions. This method can analyze compounds with fluorescence and electrochemical activities. Quinones are common organic compounds frequently used as model dissolved organic matters in water, and their redox properties are usually characterized by either electrochemical or spectroscopic methods separately. In this work, electrochemical methodology was combined with two fluorescence spectroelectrochemical techniques, cyclic volta- fluorescence spectrometry (CVF) and derivative cyclic volta- fluorescence spectrometry (DCVF), to determine the electrochemical properties of -benzoquinone in dimethyl sulfoxide, an aprotic solution. The CVF results show that the electrochemical reduction of -benzoquinone resulted in the formation of radical anion and dianion, which exhibited a lower fluorescence intensity and red-shift of the emission spectra compared to that of -benzoquinone. The fluorescence intensity was found to vary along with the electrochemical oxidation and reduction of -benzoquinone. The CVF and DCVF results were in good consistence. Thus, the combined method offers a powerful tool to investigate the electrochemical process of -benzoquinone and other natural organic compounds.

关键词： p-Benzoquinone Electrochemistry Fluorescence Spectroelectrochemistry Derivative cyclic volta fluorescence

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High butanol production by regulating carbon, redox and energy in Clostridia? ?

Jianfa Ou,Chao Ma,Ningning Xu,Yinming Du,Xiaoguang (Margaret) Liu

《化学科学与工程前沿（英文）》 2015年第9卷第3期页码 317-323 doi: 10.1007/s11705-015-1522-6

摘要： Butanol is a promising biofuel with high energy intensity and can be used as gasoline substitute. It can be produced as a sustainable energy by microorganisms (such as Clostridia) from low-value biomass. However, the low productivity, yield and selectivity in butanol fermentation are still big challenges due to the lack of an efficient butanol-producing host strain. In this article, we systematically review the host cell engineering of Clostridia, focusing on (1) various strategies to rebalance metabolic flux to achieve a high butanol production by regulating the metabolism of carbon, redox or energy, (2) the challenges in pathway manipulation, and (3) the application of proteomics technology to understand the intracellular metabolism. In addition, the process engineering is also briefly described. The objective of this review is to summarize the previous research achievements in the metabolic engineering of and provide guidance for future novel strain construction to effectively produce butanol.

关键词： Clostridia butanol biofuel metabolism carbon redox energy

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Characterization and comparison of organic functional groups effects on electrolyte performance for vanadium redox

《化学科学与工程前沿（英文）》页码 1221-1230 doi: 10.1007/s11705-023-2298-8

摘要： The vanadium redox flow battery with a safe and capacity-controllable large-scale energy storage system offers a new method for the sustainability. In this case, acetic acid, methane sulfonic acid, sulfonic acid, amino methane sulfonic acid, and taurine are used to overcome the low electrolyte energy density and stability limitations, as well as to investigate the effects of various organic functional groups on the vanadium redox flow battery. When compared to the pristine electrolyte (0.22 Ah, 5.0 Wh·L^–1, 85.0%), the results show that taurine has the advantage of maintaining vanadium ion concentrations, discharge capacity (1.43 Ah), energy density (33.9 Wh·L^–1), and energy efficiency (90.5%) even after several cycles. The acetic acid electrolyte is more conducive to the low-temperature stability of the V(II) electrolyte (177 h at −25 °C) than pristine (82 h at −2 °C). The –SO₃H group, specifically the coaction of the –NH₂ and –SO₃H groups, improves electrolyte stability. The –NH₂ and –COOH additive groups improved conductivity and electrochemical activity.

关键词： vanadium redox flow battery functional groups organic additives energy density stability

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Sustainable functionalization and modification of materials via multicomponent reactions in water

《化学科学与工程前沿（英文）》 2022年第16卷第9期页码 1318-1344 doi: 10.1007/s11705-022-2150-6

摘要： In materials chemistry, green chemistry has established firm ground providing essential design criteria to develop advanced tools for efficient functionalization and modification of materials. Particularly, the combination of multicomponent reactions in water and aqueous media with materials chemistry unlocks a new sustainable way for constructing multi-functionalized structures with unique features, playing significant roles in the plethora of applications. Multicomponent reactions have received significant consideration from the community of material chemistry because of their great efficiency, simple operations, intrinsic molecular diversity, and an atom and a pot economy. Also, by rational design of multicomponent reactions in water and aqueous media, the performance of some multicomponent reactions could be enhanced by the contributing “natural” form of water-soluble materials, the exclusive solvating features of water, and simple separating and recovering materials. To date, there is no exclusive review to report the sustainable functionalization and modification of materials in water. This critical review highlights the utility of various kinds of multicomponent reactions in water and aqueous media as green methods for functionalization and modification of siliceous, magnetic, and carbonaceous materials, oligosaccharides, polysaccharides, peptides, proteins, and synthetic polymers. The detailed discussion of synthetic procedures, properties, and related applicability of each functionalized/modified material is fully deliberated in this review.

关键词： materials multicomponent reactions modification functionalization water

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An investigation on modification mechanism of CH

Qiang XIN, Shanghong HUANG

《结构与土木工程前沿（英文）》 2017年第11卷第3期页码 293-300 doi: 10.1007/s11709-017-0403-0

摘要： Rising oil price has brought huge cost pressure for low grade highway construction, and it is urgent to find alternative resources. At the same time, there are nearly 50000–60000 tons of low temperature coal output in inner Mongolia region, China, which has high toxicity and high polluting. To make the low temperature coal be applicable for road constructions, the formaldehyde is used as cross linking agent, the concentrated sulfuric acid is used as catalyst, and the chemical modification of low temperature coal tar pitch in Inner Mongolia region is investigated. The road performance (softening point, penetration and ductility) of modified low temperature coal are tested. Results shown that the road performance of modified low temperature coal is increased significantly. Modification mechanism of low temperature coal is studied by Scanning Electron Microscopy and other analytical tools. Results show that, in the modified low temperature coal, resin content increases and the resin fiber diameter becomes larger with the increasing of formaldehyde content.

关键词： low temperature coal tar pitch modification road performance

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Research progress on low dielectric constant modification of cellulose insulating paper for power transformers

《化学科学与工程前沿（英文）》页码 991-1009 doi: 10.1007/s11705-022-2259-7

摘要： Because of the increase in the transmission voltage levels, the demand for insulation reliability of power transformers has increasingly become critical. Cellulose insulating paper is the main insulating component of power transformers. To improve the insulation level of ultrahigh voltage transformers and reduce their weight and size, reducing the dielectric constant of oil-immersed cellulose insulating paper is highly desired. Cellulose is used to produce power-transformer insulating papers owing to its excellent electrical properties, renewability, biodegradability and abundance. The dielectric constant of a cellulose insulating paper can be effectively reduced by chemical or physical modification. This study presents an overview of the foreign and domestic research status of the use of modification technology to reduce the dielectric constant of cellulose insulating papers. All the mentioned methods are analyzed in this study. Finally, some recommendations for future modified cellulose insulating paper research and applications are proposed. This paper can provide a reference for further research on low dielectric constant cellulose insulating paper in the future.

关键词： low dielectric constant chemical and physical modification cellulose insulating paper transformer nanomaterials.

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Nitrifying population dynamics in a redox stratified membrane biofilm reactor (RSMBR) for treating ammonium-rich

Rongchang WANG, Xinmin ZHAN, Yalei ZHANG, Jianfu ZHAO

《环境科学与工程前沿（英文）》 2011年第5卷第1期页码 48-56 doi: 10.1007/s11783-011-0305-7

摘要： Nitrogen removal performance and nitrifying population dynamics were investigated in a redox stratified membrane biofilm reactor (RSMBR) under oxygen limited condition to treat ammonium-rich wastewater. When the loading rate increased from 11.1±1.0 to , the nitrogen removal in the RSMBR system increased from 18.0±9.6 mgN·d to 128.9±61.7 mgN·d . Shortcut nitrogen removal was achieved with nitrite accumulation of about . Confocal micrographs showed the stratified distributions of nitrifiers and denitrifiers in the membrane aerated biofilms (MABs) at day 120, i.e., ammonia and nitrite oxidizing bacteria (AOB and NOB) were dominant in the region adjacent to the membrane, while heterotrophic bacteria propagated at the top of the biofilm. Real-time qPCR results showed that the abundance of gene was two orders of magnitude higher than the abundance of gene in the MABs. However, the gene was always detected during the operation time, which indicates the difficulty of complete washout of NOB in MABs. The growth of heterotrophic bacteria compromised the dominance of nitrifiers in biofilm communities, but it enhanced the denitrification performance of the RSMBR system. Applying a high ammonia loading together with oxygen limitation was found to be an effective way to start nitrite accumulation in MABs, but other approaches were needed to sustain or improve the extent of nitritation in nitrogen conversion in MABs.

关键词： ammonium-rich wastewater membrane biofilm reactor nitrification redox stratification shortcut nitrogen removal

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Crystal modification of rifapentine using different solvents

Kun ZHOU, Jun LI, Jianhong LUO, Dongsheng ZHENG,

《化学科学与工程前沿（英文）》 2010年第4卷第1期页码 65-69 doi: 10.1007/s11705-009-0302-6

摘要： Rifapentine crystals with different habits were prepared by recrystallization from selected solvents, such as methanol, ethanol, chloroform, and acetic acid. Scanning electron microscopy, X-ray powder diffractometry, infrared spectrometry, and differential scanning calorimetry were used to investigate the physicochemical characteristics of the prepared crystals. The comparative dissolution behaviors of the newly developed crystals and of rifapentine without being treated were also studied. Results show that the newly developed crystals were different from each other with respect to physical properties but were identical chemically. Needle-shaped crystals were obtained from methanol, ethanol, and chloroform solvents, and the block-shaped crystals were obtained from acetic acid solvent. X-ray diffraction spectra and differential scanning calorimetry investigation on those developed crystals clearly indicate that rifapentine has different crystal structure modification. When the crystal was obtained from acetic acid, the change of crystal habit was originated from the crystal structure modification. The dissolution rate of newly developed crystals was found to be higher than that of rifapentine without being treated. However, the modified crystal obtained from acetic acid shows the lower dissolution rate than crystals obtained from other solvents.

关键词： identical scanning calorimetry different comparative dissolution structure modification

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Persistent free radicals in humin under redox conditions and their impact in transforming polycyclic

Hanzhong Jia, Yafang Shi, Xiaofeng Nie, Song Zhao, Tiecheng Wang, Virender K. Sharma

《环境科学与工程前沿（英文）》 2020年第14卷第4期 doi: 10.1007/s11783-020-1252-y

摘要： Abstract • Regulation of redox conditions promotes the generation of free radicals on HM. • HM-PFRs can be fractionated into active and inactive types depending on stability. • The newly produced PFRs readily release electrons to oxygen and generate ROS. • PFR-induced ROS mediate the transformation of organic contaminants adsorbed on HM. The role of humic substance-associated persistent free radicals (PFRs) in the fate of organic contaminants under various redox conditions remains unknown. This study examined the characterization of original metal-free peat humin (HM), and HM treated with varying concentrations of H2O2 and L-ascorbic acid (VC) (assigned as H2O2-HM and VC-HM). The concentration of PFRs in HM increased with the addition of VC/H2O2 at concentrations less than 0.08 M. The evolution of PFRs in HM under different environmental conditions (e.g., oxic/anoxic and humidity) was investigated. Two types of PFRs were detected in HM: a relatively stable radical existed in the original sample, and the other type, which was generated by redox treatments, was relatively unstable. The spin densities of VC/H2O2-HM readily returned to the original value under relatively high humidity and oxic conditions. During this process, the HM-associated “unstable” free radicals released an electron to O2, inducing the formation of reactive oxygen species (ROS, i.e., •OH and •O2−). The generated ROS promoted the degradation of polycyclic aromatic hydrocarbons based on the radical quenching measurements. The transformation rates followed the order naphthalene>phenanthrene>anthracene>benzo[a]pyrene. Our results provide valuable insight into the HM-induced transformation of organic contaminants under natural conditions.

关键词： Humic substance Polycyclic aromatic hydrocarbons (PAHs) Persistent free radicals (PFRs) Redox Reactive oxygen species (ROS)

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Surface modification techniques of membranes to improve their antifouling characteristics: recent advancements

《化学科学与工程前沿（英文）》 doi: 10.1007/s11705-023-2347-3

摘要： Surface modification techniques of membranes to improve their antifouling characteristics: recent advancements and developments

关键词： Surface modification techniques

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Pressure drop analysis on the positive half-cell of a cerium redox flow battery using computational fluid

Fernando F. Rivera, Berenice Miranda-Alcántara, Germán Orozco, Carlos Ponce de León, Luis F. Arenas

《化学科学与工程前沿（英文）》 2021年第15卷第2期页码 399-409 doi: 10.1007/s11705-020-1934-9

摘要： Description of electrolyte fluid dynamics in the electrode compartments by mathematical models can be a powerful tool in the development of redox flow batteries (RFBs) and other electrochemical reactors. In order to determine their predictive capability, turbulent Reynolds-averaged Navier-Stokes (RANS) and free flow plus porous media (Brinkman) models were applied to compute local fluid velocities taking place in a rectangular channel electrochemical flow cell used as the positive half-cell of a cerium-based RFB for laboratory studies. Two different platinized titanium electrodes were considered, a plate plus a turbulence promoter and an expanded metal mesh. Calculated pressure drop was validated against experimental data obtained with typical cerium electrolytes. It was found that the pressure drop values were better described by the RANS approach, whereas the validity of Brinkman equations was strongly dependent on porosity and permeability values of the porous media.

关键词： CFD simulation porous media porous electrode pressure drop redox flow battery

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Redox flow batteries—Concepts and chemistries for cost-effective energy storage

Matthäa Verena HOLLAND-CUNZ, Faye CORDING, Jochen FRIEDL, Ulrich STIMMING

《能源前沿（英文）》 2018年第12卷第2期页码 198-224 doi: 10.1007/s11708-018-0552-4

摘要： Electrochemical energy storage is one of the few options to store the energy from intermittent renewable energy sources like wind and solar. Redox flow batteries (RFBs) are such an energy storage system, which has favorable features over other battery technologies, e.g. solid state batteries, due to their inherent safety and the independent scaling of energy and power content. However, because of their low energy-density, low power-density, and the cost of components such as redox species and membranes, commercialised RFB systems like the all-vanadium chemistry cannot make full use of the inherent advantages over other systems. In principle, there are three pathways to improve RFBs and to make them viable for large scale application: First, to employ electrolytes with higher energy density. This goal can be achieved by increasing the concentration of redox species, employing redox species that store more than one electron or by increasing the cell voltage. Second, to enhance the power output of the battery cells by using high kinetic redox species, increasing the cell voltage, implementing novel cell designs or membranes with lower resistance. The first two means reduce the electrode surface area needed to supply a certain power output, thereby bringing down costs for expensive components such as membranes. Third, to reduce the costs of single or multiple components such as redox species or membranes. To achieve these objectives it is necessary to develop new battery chemistries and cell configurations. In this review, a comparison of promising cell chemistries is focused on, be they all-liquid, slurries or hybrids combining liquid, gas and solid phases. The aim is to elucidate which redox-system is most favorable in terms of energy-density, power-density and capital cost. Besides, the choice of solvent and the selection of an inorganic or organic redox couples with the entailing consequences are discussed.

关键词： electrochemical energy storage redox flow battery vanadium

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Feasibility of bubble surface modification for natural organic matter removal from river water using

Yulong Shi, Jiaxuan Yang, Jun Ma, Congwei Luo

《环境科学与工程前沿（英文）》 2017年第11卷第6期 doi: 10.1007/s11783-017-0954-2

摘要： A novel, functionalized bubble surface can be obtained in dissolved air flotation (DAF) by dosing chemicals in the saturator. In this study, different cationic chemicals were used as bubble surface modifiers, and their effects on natural organic matter (NOM) removal from river water were investigated. NOM in the samples was fractionated based on molecular weight and hydrophobicity. The disinfection byproduct formation potentials of each fraction and their removal efficiencies were also evaluated. The results showed that chitosan was the most promising bubble modifier compared with a surfactant and a synthetic polymer. Tiny bubbles in the DAF pump system facilitated the adsorption of chitosan onto microbubble surfaces. The hydrophobic NOM fraction was preferentially removed by chitosan-modified bubbles. Decreasing the recycle water pH from 7.0 to 5.5 improved the removal of hydrophilic NOM with low molecular weight. Likewise, hydrophilic organic compounds gave high dihaloacetic acid yields in raw water. An enhanced reduction of haloacetic acid precursors was obtained with recycle water at pH values of 5.5 and 4.0. The experimental results indicate that NOM fractions may interact with bubbles through different mechanisms. Positive bubble modification provides an alternative approach for DAF to enhance NOM removal.

关键词： Bubble surface modification Chitosan Disinfection by-product Dissolved air flotation Organic fraction

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RNA m⁶A modification and its function in diseases

null

《医学前沿（英文）》 2018年第12卷第4期页码 481-489 doi: 10.1007/s11684-018-0654-8

摘要：

N⁶-methyladenosine (m⁶A) is the most common post-transcriptional RNA modification throughout the transcriptome, affecting fundamental aspects of RNA metabolism. m⁶A modification could be installed by m⁶A “writers” composed of core catalytic components (METTL3/METTL14/WTAP) and newly defined regulators and removed by m⁶A “erasers” (FTO and ALKBH5). The function of m⁶A is executed by m⁶A “readers” that bind to m⁶A directly (YTH domain-containing proteins, eIF3 and IGF2BPs) or indirectly (HNRNPA2B1). In the past few years, advances in m⁶A modulators (“writers,” “erasers,” and “readers”) have remarkably renewed our understanding of the function and regulation of m⁶A in different cells under normal or disease conditions. However, the mechanism and the regulatory network of m⁶A are still largely unknown. Moreover, investigations of the m⁶A physiological roles in human diseases are limited. In this review, we summarize the recent advances in m⁶A research and highlight the functional relevance and importance of m⁶A modification in in vitro cell lines, in physiological contexts, and in cancers.

关键词： RNA modification m⁶A immunity cancer epigenetics

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标题作者时间类型操作

Oxidative stress and diabetes: antioxidative strategies

Pengju Zhang, Tao Li, Xingyun Wu, Edouard C. Nice, Canhua Huang, Yuanyuan Zhang

期刊论文

Probing the redox process of

Rui Lu, Wei Chen, Wen-Wei Li, Guo-Ping Sheng, Lian-Jun Wang, Han-Qing Yu

期刊论文

High butanol production by regulating carbon, redox and energy in Clostridia? ?

Jianfa Ou,Chao Ma,Ningning Xu,Yinming Du,Xiaoguang (Margaret) Liu

期刊论文

Characterization and comparison of organic functional groups effects on electrolyte performance for vanadium redox

期刊论文

Sustainable functionalization and modification of materials via multicomponent reactions in water

期刊论文

An investigation on modification mechanism of CH

Qiang XIN, Shanghong HUANG

期刊论文

Research progress on low dielectric constant modification of cellulose insulating paper for power transformers

期刊论文

Nitrifying population dynamics in a redox stratified membrane biofilm reactor (RSMBR) for treating ammonium-rich

Rongchang WANG, Xinmin ZHAN, Yalei ZHANG, Jianfu ZHAO

期刊论文

Crystal modification of rifapentine using different solvents

Kun ZHOU, Jun LI, Jianhong LUO, Dongsheng ZHENG,

期刊论文

Persistent free radicals in humin under redox conditions and their impact in transforming polycyclic

Hanzhong Jia, Yafang Shi, Xiaofeng Nie, Song Zhao, Tiecheng Wang, Virender K. Sharma

期刊论文

Surface modification techniques of membranes to improve their antifouling characteristics: recent advancements

期刊论文

Pressure drop analysis on the positive half-cell of a cerium redox flow battery using computational fluid

Fernando F. Rivera, Berenice Miranda-Alcántara, Germán Orozco, Carlos Ponce de León, Luis F. Arenas

期刊论文

Redox flow batteries—Concepts and chemistries for cost-effective energy storage

Matthäa Verena HOLLAND-CUNZ, Faye CORDING, Jochen FRIEDL, Ulrich STIMMING

期刊论文

Feasibility of bubble surface modification for natural organic matter removal from river water using

Yulong Shi, Jiaxuan Yang, Jun Ma, Congwei Luo

期刊论文

RNA m⁶A modification and its function in diseases

null

期刊论文

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