In this study,carboxymethylation,which introduces carboxyl groups to hydroxyl sites in pulp fibers,was used as a pretreatment before mechanical nanofibrillation.The carboxyl group content of the pulp fibers was greatl...In this study,carboxymethylation,which introduces carboxyl groups to hydroxyl sites in pulp fibers,was used as a pretreatment before mechanical nanofibrillation.The carboxyl group content of the pulp fibers was greatly affected by the dosage of chloroacetic acid and the reaction temperature.During the following fibrillation process,it was found that pulp fibers with higher carboxyl group content exhibited higher water holding capacities and smaller dimensions.A more homogenous structure with a higher amount of individual fibrils was also observed in FE-SEM images of pulp fibers with high carboxyl group content.This can be explained by a high ionic group content in the fiber wall resulting in lower delamination resistance,making the fibrils easier to separate.Carboxymethylation pretreatment as a facilitator of fibrillation in cellulosic pulps is an efficient way to obtain cellulose nanofibrils and consequently decrease the energy consumption of the process.展开更多
The Iead compound of substituted 2-(4-hydroxyphenyl)benzimidazol were modified by phos-phorylation sulfonation and carboxymethylation. The henzimldazoloamidophosphate (6) (7) have better activi-ty against tobacco mosa...The Iead compound of substituted 2-(4-hydroxyphenyl)benzimidazol were modified by phos-phorylation sulfonation and carboxymethylation. The henzimldazoloamidophosphate (6) (7) have better activi-ty against tobacco mosaic virus (TMV). The benzimldazolophenoxyacetic acid, phenoxysuIfonic acid c0ntaining tri flu0r0methyl, and nitro gr0up have 77% ~85% efflclency f0r wheat rust disease.展开更多
To investigate the structure-activity relationship of polysaccharide and obtain a better antidepressant polysaccharide,the antidepressant-like activity of a carboxymethyl polysaccharide(C-MEPS2)subjected to submerged ...To investigate the structure-activity relationship of polysaccharide and obtain a better antidepressant polysaccharide,the antidepressant-like activity of a carboxymethyl polysaccharide(C-MEPS2)subjected to submerged fermentation was systematically studied.PC12-H cell and Kunming mice were used to investigate the differences and their mechanism in the antidepressant effects of C-MEPS2 and MEPS2.Cell experiments have showed that C-MEPS2 has a better antidepressant effect than MEPS2.C-MEPS2 could exert antidepressant effects related to catecholamine synthesis with specifi c sites of TH,D2DR,and P-CAMKII.In addition,C-MEPS2 could repair the Res-induced damage in PC12-H cell,stabilize the mitochondrial membrane potential and regulate intracellular Ca^(2+) concentration,thus reducing cell apoptosis caused by RES.Antagonists common dosing experiments on animals further proved that CMEPS2 could signifi cantly improve the antidepressant effect of derivatives without affecting the antidepressant mechanism of MEPS2.It is speculated that it may be related to carboxymethylated modifi cation.展开更多
Aqueous zinc metal batteries have garnered substantial attention ascribing to affordability,intrinsic safety,and environmental benignity Nevertheless,zinc metal batteries yet are challenged with potential service life...Aqueous zinc metal batteries have garnered substantial attention ascribing to affordability,intrinsic safety,and environmental benignity Nevertheless,zinc metal batteries yet are challenged with potential service life issues resulted from dendrites and side reaction.In this paper,a strategy of nanoparticles doped hydrogel is proposed for constructing carboxymethyl cellulose/graphite oxide hybrid hydrogel electrolyte membranes with exceptional ionic conductivity,anti-swelling property,and simultaneously addressing the dendrites and parasitic reaction.The pivotal functions of the carboxymethyl cellulose/graphite oxide hydrogel electrolyte in mitigating hydrogen evolution and fostering accelerated Zn deposition have been elucidated based on principles of thermodynamic and reaction kinetic.The carboxymethyl cellulose/graphite oxide hydrogel electrolyte endows exceptional cycling longevity(800 h at 1 mA cm^(-2)/1 mAh cm^(-2))for Znjj Zn battery,as well as high Coulombic efficiency for Znjj Cu battery(averagely 99.14%within 439 cycles at 1 mA cm^(-2)/1 mAh cm^(-2)).The assembled Znjj NH_(4)V_(4)O_(10)battery delivers a high reversible specific capacity of 328.5 mAh g^(-1)at 0.1 A g^(-1).Moreover,the device of Znjj NH_(4)V_(4)O_(10)pouch battery remains operational under severe conditions like bending and cutting.This work provides valuable reference in developing inorganic nanoparticle hybrid hydrogel electrolyte for realizing high-performance zinc metal batteries.展开更多
This study prepared and characterized amphiphilic carboxymethyl cellulose stearate(CMCS)recycled from sugarcane bagasse agro-waste(SB).The Fourier-transform infrared(FTIR)analysis confirmed cellulose,carboxymethyl cel...This study prepared and characterized amphiphilic carboxymethyl cellulose stearate(CMCS)recycled from sugarcane bagasse agro-waste(SB).The Fourier-transform infrared(FTIR)analysis confirmed cellulose,carboxymethyl cellulose(CMC),and CMCS structures,with CMCS showing increased H-bonding.X-ray diffraction analysis(XRD)revealed reduced crystallinity in CMC and CMCS.CMCS exhibited a hydrophobic nature but dispersed in water,enabling nanoemulsion formation.Optimal nanoemulsion was achieved with CMCS1,showing a particle size of 99 nm.Transmission electron microscopy(TEM)images revealed CMC’s honeycomb structure,transforming into spherical particles in CMCS1.Antimicrobial tests demonstrated strong activity of CMCS formulations against Escherichia coli and Staphylococcus aureus,with CMCS3 exhibiting the highest efficacy.These findings highlight the potential of CMCS-based nanoemulsions for antimicrobial applications and nanoemulsification.展开更多
Biodegradable packaging has emerged as a viable alternative to non-biodegradable polymers.This study explores different treatments of agar-carboxymethyl cellulose(CMC)nanocomposites developed via the casting method.We...Biodegradable packaging has emerged as a viable alternative to non-biodegradable polymers.This study explores different treatments of agar-carboxymethyl cellulose(CMC)nanocomposites developed via the casting method.We investigated the effects of varying glycerol levels(20%-60%)as a plasticizer and nanocellulose levels(0%-30%)as a filler on the properties of agar-CMC nanocomposites.Key properties analyzed included water vapor permeability,solubility in water,moisture absorption,water contact angle,color properties,and mechanical properties.The films exhibited low water vapor permeability,ranging from 2.50×10^(-11) g/msPa to 2.23×10^(-12) g/msPa.Water solubility of the films was below 40%,except for the film containing 60%glycerol.Despite this,all samples demonstrated very low moisture absorption.The water droplet contact angle tests indicated that the film surfaces were moderately hydrophilic.Increasing the nanocellulose content further enhanced the hydrophilicity of the surfaces.The maximum tensile strength and elongation at break recorded were 31.09 MPa and 46.2%,respectively.While adding glycerol reduced tensile strength,it improved elongation at break.Visual observations and color evaluation revealed that the films were transparent,with a low total color difference and a low yellow index.The simultaneous use of both agar and carboxymethyl cellulose polymers in biocomposite formulation successfully mitigated the disadvantages associated with each biopolymer when used alone,thereby enhancing their functional properties.展开更多
With the increasing prevalence of lithium-ion batteries(LIBs)applications,the demand for high-capacity next-generation materials has also increased.SiO_(x)is currently considered a promising anode material due to its ...With the increasing prevalence of lithium-ion batteries(LIBs)applications,the demand for high-capacity next-generation materials has also increased.SiO_(x)is currently considered a promising anode material due to its exceptionally high capacity for LIBs.However,the significant volumetric changes of SiO_(x)during cycling and its initial Coulombic efficiency(ICE)complicate its use,whether alone or in combination with graphite materials.In this study,a three-dimensional conductive binder network with high electronic conductivity and robust elasticity for graphite/SiO_(x)blended anodes was proposed by chemically anchoring carbon nanotubes and carboxymethyl cellulose binders using tannic acid as a chemical cross-linker.In addition,a dehydrogenation-based prelithiation strategy employing lithium hydride was utilized to enhance the ICE of SiO_(x).The combination of these two strategies increased the CE of SiO_(x)from 74%to87%and effectively mitigated its volume expansion in the graphite/SiO_(x)blended electrode,resulting in an efficient electron-conductive binder network.This led to a remarkable capacity retention of 94%after30 cycles,even under challenging conditions,with a high capacity of 550 mA h g^(-1)and a current density of 4 mA cm^(-2).Furthermore,to validate the feasibility of utilizing prelithiated SiO_(x)anode materials and the conductive binder network in LIBs,a full cell incorporating these materials and a single-crystalline Ni-rich cathode was used.This cell demonstrated a~27.3%increase in discharge capacity of the first cycle(~185.7 mA h g^(-1))and exhibited a cycling stability of 300 cycles.Thus,this study reports a simple,feasible,and insightful method for designing high-performance LIB electrodes.展开更多
Nano zero-valent iron(nZVI)is widely used in soil remediation due to its high reactivity.However,the easy agglomeration,poor antioxidant ability and passivation layer of Fe-Cr coprecipitates of nZVI have limited its a...Nano zero-valent iron(nZVI)is widely used in soil remediation due to its high reactivity.However,the easy agglomeration,poor antioxidant ability and passivation layer of Fe-Cr coprecipitates of nZVI have limited its application scale in Cr-contaminated soil remediation,especially in high concentration of Cr-contaminated soil.Herein,we found that the carboxymethyl cellulose on nZVI particles could increase the zeta potential value of soil and change the phase of nZVI.Along with the presence of biochar,97.0%and 96.6%Cr immobilization efficiency through CMC-nZVI/BC were respectively achieved in high and low concentrations of Cr-contaminated soils after 90-days remediation.In addition,the immobilization efficiency of Cr(VI)only decreased by 5.1%through CMC-nZVI/BC treatment after 10 weeks aging in air,attributing to the strong antioxidation ability.As for the surrounding Crcontaminated groundwater,the Cr(VI)removal capacity of CMC-nZVI/BC was evaluated under different reaction conditions through column experiments and COMSOL Multiphysics.CMC-nZVI/BC could efficiently remove 85%of Cr(VI)in about 400 hr when the initial Cr(VI)concentration was 40 mg/L and the flow rate was 0.5 mL/min.This study demonstrates that uniformly dispersed CMC-nZVI/BC has an excellent remediation effect on different concentrations of Cr-contaminated soils.展开更多
The lanthanum-cerium-based slurry(LC-slurry)is extensively utilized in the chemical mechanical polishing(CMP)of TFT-LCD glass substrates,optical lenses,and other glass products.Sodium hexametaphosphate(SHMP),as a disp...The lanthanum-cerium-based slurry(LC-slurry)is extensively utilized in the chemical mechanical polishing(CMP)of TFT-LCD glass substrates,optical lenses,and other glass products.Sodium hexametaphosphate(SHMP),as a dispersant,is commonly employed to enhance the dispersion properties of LCslurry for improved polishing performance.However,the tendency of sedimentation to form a compacted sediment layer,which is challenging to redisperse,increases storage difficulty and polishing equipment failure risk,thereby limiting its utilization in CMP.In the present study,sodium carboxymethylcellulose(CMC-Na),a long-chain organic polymer,was employed to enhance the redispersibility of LC-slurry containing SHMP.A comprehensive investigation was conducted on the influence of CMC-Na dosage and slurry pH on dispersibility,redispersibility and polishing performance.Additionally,an analysis was carried out to elucidate the underlying mechanism behind the effect of CMC-Na.The study demonstrates that the LC-slurry,containing 250 ppm SHMP and 500 ppm CMC-Na,exhibits excellent dispersibility and redispersibility.Further polishing tests demonstrate that compared to the LC-slurry containing only SHMP,utilizing the slurry containing both SHMP and CMC-Na at various pH for polishing thin film transistor liquid crystal display(TFT-LCD)glass substrates results in a reduction of both material removal rate(MRR)and surface roughness(Sa).Specifically,when adjusting the slurry to a pH range of 5-6,the MRR can reach up to 330 nm/min,which closely approximates the MRR achieved by LC-slurry containing only 250 ppm SHMP at corresponding pH values.Meanwhile,after polishing,the surface roughness of the glass substrate measures approximately 0.47 nm.展开更多
The management of chronic wounds remains a substantial challenge for healthcare providers. Inadequate wound care can result in serious complications, including infection, which may ultimately lead to amputation or eve...The management of chronic wounds remains a substantial challenge for healthcare providers. Inadequate wound care can result in serious complications, including infection, which may ultimately lead to amputation or even death. While traditional excipients exhibit some efficacy in promoting wound healing, they are not sufficiently effective in preventing wound infections. As an antimicrobial metal, copper has a long history in the antimicrobial field, and at the same time, wound auxiliaries with copper ions have also been used in the treatment of chronic wounds. To address the limitations of conventional wound dressings, including insufficient antimicrobial properties and limited capacity to promote wound healing, this study introduces a highly adhesive hydrogel with superior mechanical stability for non-invasive wound treatment. The hydrogel was composed of carboxymethyl chitosan, tannic acid and copper ions. The tannic acid solution was subjected to dropwise addition of CuCl2 solution to produce precipitation, and tannic acid/copper ions (TA/Cu2+) composite nanoparticles were prepared. Through topological adhesion, the CMCS with pH sensitivity has the ability to establish adhesive connections with a wide range of materials. The benefits of CMCS/TA/Cu2+ hydrogel, as a kind of wound closure and repair material, include efficient wound closure, and resistance against bacterial invasion while maintaining cleanliness. Additionally, it exhibits excellent tensile and mechanical stability that can facilitate effective closure and repair in dynamic areas like joint wounds. This promising hydrogel adhesive has demonstrated potential as a material for wound closure and restoration.展开更多
Carboxymethyl starchs（CMS） with low and high degrees of substitution（CMSL and CMSH in short,respectively） were employed as depressants of diaspore in cationic reverse flotation using dodecylamine（DDA） as collect...Carboxymethyl starchs（CMS） with low and high degrees of substitution（CMSL and CMSH in short,respectively） were employed as depressants of diaspore in cationic reverse flotation using dodecylamine（DDA） as collector.The effect of degree of substitution of CMS on its depression performance was examined and the interaction mode and behavior were investigated in a comparative manner.Micro-flotation test showed that CMSL exhibited better performance in depressing diaspore than CMSH in a broad pH range.The adsorption of CMS on diaspore was studied by adsorption test,zeta potential measurement,and atomic force microscopy.It was found that CMSH corresponds to lower adsorption amount,thinner adsorption layer,and more negative charge than CMSL,resulting from the more chelating sites brought by the high degree of substitution.The surface tension measurement and DDA adsorption test further revealed that CMSL/DDA system gives a better depressing performance benefiting from the trapping effect by enveloping some DDA molecules inside the loop chains,while CMSH/DDA system is likely considered a quasi-surfactant.展开更多
[Objective] In order to study the relations among different positions, degrees of substitution and antioxidant ability. [Method] N, O-carboxymethyl chitosan （NOA, NOB and NOC）with various degrees of substitution （D...[Objective] In order to study the relations among different positions, degrees of substitution and antioxidant ability. [Method] N, O-carboxymethyl chitosan （NOA, NOB and NOC）with various degrees of substitution （DS）were obtained by etherizing chito-oligosacchaside. Their structure and substituted degree were characterized and their antioxldant activity to·OH was evaluated. [ Result] The IC50 s of NOA ,NOB and NOC were 0.15 ,0. 29 ,0. 23 mg/ml while their DSs of -NH2 position（DSN） were 0.51,0.29 and 0.38 and DSo were 0. 74 ,0. 84 ,0. 97respectively.[ Conclusion] With the increase of DSN ,antioxidant activity of N,O-carboxymethyl chitosan oligosaccharide to·OH was up.展开更多
The effects of copper ions and calcium ions on the depression of chlorite using CMC（carboxymethyl cellulose） as a depressant were studied through flotation tests,adsorption measurements,ζ potential tests and co-pre...The effects of copper ions and calcium ions on the depression of chlorite using CMC（carboxymethyl cellulose） as a depressant were studied through flotation tests,adsorption measurements,ζ potential tests and co-precipitation experiments.The results show that the electrostatic repulsion between the CMC molecules and the chlorite surfaces hinders the approach of the CMC to the chlorite while the presence of copper ions and calcium ions enhances the adsorption density of CMC.The action mechanisms of these two types of ions are different.Calcium ions can not adsorb onto the mineral surfaces,but they can interact with the CMC molecules,thus reducing the charge of the CMC and enhancing adsorption density.Copper ions can adsorb onto the mineral surfaces,which facilitates the CMC adsorption through acid/base interaction.The enhanced adsorption density is also attributed to the decreased electrostatic repulsion between the CMC and mineral surfaces as copper ions reduce the surface charge of both the mineral surfaces and the CMC molecules.展开更多
A new solvent of cellulose (1.5 mol/L NaOH/0.5 mol/L urea aqueous solution) was used as one of the homogeneous reaction media of polysaccharides for methylation, hydroxyethylation and hydroxypropylation. A water insol...A new solvent of cellulose (1.5 mol/L NaOH/0.5 mol/L urea aqueous solution) was used as one of the homogeneous reaction media of polysaccharides for methylation, hydroxyethylation and hydroxypropylation. A water insoluble β -(1—>3)-D-glucan, sample PCS3- isolated from fresh sclerotium of Poria cocos was sulfated in dimethyl sulfoxide (Me 2 SO), carboxymethylated in NaOH, isopropanol solution, as well as methylated, hydroxyethylated and hydroxypropylated in the new solvent system, respectively, to obtain five water-soluble derivatives coded as S-PCS3- C- PCS3- M-PCS3- HE-PCS3- and HP-PCS3- Their chemical structure and distribution of substitution were characterized by infrared spectroscopy (IR), elementary analysis (EA), 1 H-NMR, 13 C-NMR, 2D-COSY, 2D-TOCSY and 2D- 1 H-detected 1H 13C HMQC spectra. The results reveal that the relative reactivity of hydroxyl groups of the β -(1-?3)-D-glucan is in the order C-6 > C-4 > C-2 on the whole. The substitution of the samples S-PCS3- C-PCS3- and M-PCS3- occurred mainly at C-6 position and secondly at C-4 and C-2 positions, and that of HE-PCS3- occurred at C-6 and C-4 positions and of HP-PCS3- almost completely occurred at C-6 position. The degrees of substitution (DS) obtained from 13 C-NMR range from 0.23 to 1.27. The water solubility of the derivatives is in the order S-PCS3- >C-PCS3- >M-PCS3- >HE-PCS3- >HP-PCS3- This work provides a novel and nonpolluting process for the methylation, hydroxyethylation and hydroxypropylation of β -(1—>3)-D-glucan.展开更多
Advanced glycation end-products （AGEs） are products of non-enzymatic glycation of proteins, lipids or nucleic acids and other macromolecules. To be spe- cific, Nε-（carboxymethyl）-Iysine （CML） is one of the most...Advanced glycation end-products （AGEs） are products of non-enzymatic glycation of proteins, lipids or nucleic acids and other macromolecules. To be spe- cific, Nε-（carboxymethyl）-Iysine （CML） is one of the most important components of AGEs, which is wildly distributed in the body and can be formed in vivo or in food processing and heating processes. Previous studies have shown that CML is a ma- jor immunological epitope in AGEs and plays an important role in diabetes and its complications, as well as in the development and progression of aging. This review summarized recent advances in major source, toxicological hazard and control mea- sures of CML.展开更多
A linear alpha -D-(1-->3)-glucan, named PSG, was obtained from the spores of Ganoderma lucidum. The synthesis of positively and negatively charged polyelectrolytes from PSG was developed. Amine groups and carboxyme...A linear alpha -D-(1-->3)-glucan, named PSG, was obtained from the spores of Ganoderma lucidum. The synthesis of positively and negatively charged polyelectrolytes from PSG was developed. Amine groups and carboxymethyl groups were introduced through nucleophilic substitution with 3-chloropropylamine or chloroacetic acid, respectively, Reaction conditions were varied to obtain insight into the influence of variables on the degree of substitution.展开更多
Crude seed gum and their carboxymethyl derivatives from Tamarindus indica and Cassia fistula seeds were developed and characterized to apply as the pharmaceutical disintegrant in fast disintegrating Thai cordial table...Crude seed gum and their carboxymethyl derivatives from Tamarindus indica and Cassia fistula seeds were developed and characterized to apply as the pharmaceutical disintegrant in fast disintegrating Thai cordial tablet. The chemical structure of crude gum was chemically modified via carboxymethylation. Degree of substitution(DS) of carboxymethylated gums was determined. Carboxymethylated gums with minimum and maximum DS values were chosen for further application. IR absorption spectra of gum samples were observed to verify their chemical structure changes. In physical properties, the intrinsic viscosity and swelling property of all gum samples were evaluated. The results showed that carboxymethylated gums had higher intrinsic viscosity than those of crude gum. Moreover, they could swell and be soluble in cold water better than those of crude gums. In conclusion, the modified gums from both plants could provide higher hardness and be better used than that crude gums for fast disintegrating Thai cordial tablet. However, this is a preliminary assessment to expressing pharmaceutical application possibility of these gums as disintegrants, diluents and drug release controlling agents.展开更多
基金financial support from the National Key Research and Development Program of China (Grant No.2017YFB0307900)the National Natural Science Foundation of China (Grant No.31470602,31670595,31770628)the Taishan Scholars Program
文摘In this study,carboxymethylation,which introduces carboxyl groups to hydroxyl sites in pulp fibers,was used as a pretreatment before mechanical nanofibrillation.The carboxyl group content of the pulp fibers was greatly affected by the dosage of chloroacetic acid and the reaction temperature.During the following fibrillation process,it was found that pulp fibers with higher carboxyl group content exhibited higher water holding capacities and smaller dimensions.A more homogenous structure with a higher amount of individual fibrils was also observed in FE-SEM images of pulp fibers with high carboxyl group content.This can be explained by a high ionic group content in the fiber wall resulting in lower delamination resistance,making the fibrils easier to separate.Carboxymethylation pretreatment as a facilitator of fibrillation in cellulosic pulps is an efficient way to obtain cellulose nanofibrils and consequently decrease the energy consumption of the process.
文摘The Iead compound of substituted 2-(4-hydroxyphenyl)benzimidazol were modified by phos-phorylation sulfonation and carboxymethylation. The henzimldazoloamidophosphate (6) (7) have better activi-ty against tobacco mosaic virus (TMV). The benzimldazolophenoxyacetic acid, phenoxysuIfonic acid c0ntaining tri flu0r0methyl, and nitro gr0up have 77% ~85% efflclency f0r wheat rust disease.
基金funded by the Natural Science Foundation of China(32072203)the Tianjin Municipal Education Commission(TD13-5013)+4 种基金the Open Project of State Key Laboratory of Food Nutrition and Safety,Tianjin University of Science&Technology(SKLFNS-KF-202102)Natural Science Foundation of Shanxi(201901D211130)Scientific and Technological Innovation Programs of Higher Education Institutions in Shanxi(2017105)Tianjin synthetic biotechnology innovation capacity improvement project(TSBICIP-KJGG-016)Tianjin Science and Technology Plan Project(21ZYJDJC00030).
文摘To investigate the structure-activity relationship of polysaccharide and obtain a better antidepressant polysaccharide,the antidepressant-like activity of a carboxymethyl polysaccharide(C-MEPS2)subjected to submerged fermentation was systematically studied.PC12-H cell and Kunming mice were used to investigate the differences and their mechanism in the antidepressant effects of C-MEPS2 and MEPS2.Cell experiments have showed that C-MEPS2 has a better antidepressant effect than MEPS2.C-MEPS2 could exert antidepressant effects related to catecholamine synthesis with specifi c sites of TH,D2DR,and P-CAMKII.In addition,C-MEPS2 could repair the Res-induced damage in PC12-H cell,stabilize the mitochondrial membrane potential and regulate intracellular Ca^(2+) concentration,thus reducing cell apoptosis caused by RES.Antagonists common dosing experiments on animals further proved that CMEPS2 could signifi cantly improve the antidepressant effect of derivatives without affecting the antidepressant mechanism of MEPS2.It is speculated that it may be related to carboxymethylated modifi cation.
基金supported by the National Natural Science Foundation of China(51763014 and 52073133)Key Talent Project Foundation of Gansu Province+1 种基金Joint fund between Shenyang National Laboratory for Materials Science and State Key Laboratory of Advanced Processing and Recycling of Nonferrous Metals(18LHPY002)the Program for Hong Liu Distinguished Young Scholars in Lanzhou University of Technology。
文摘Aqueous zinc metal batteries have garnered substantial attention ascribing to affordability,intrinsic safety,and environmental benignity Nevertheless,zinc metal batteries yet are challenged with potential service life issues resulted from dendrites and side reaction.In this paper,a strategy of nanoparticles doped hydrogel is proposed for constructing carboxymethyl cellulose/graphite oxide hybrid hydrogel electrolyte membranes with exceptional ionic conductivity,anti-swelling property,and simultaneously addressing the dendrites and parasitic reaction.The pivotal functions of the carboxymethyl cellulose/graphite oxide hydrogel electrolyte in mitigating hydrogen evolution and fostering accelerated Zn deposition have been elucidated based on principles of thermodynamic and reaction kinetic.The carboxymethyl cellulose/graphite oxide hydrogel electrolyte endows exceptional cycling longevity(800 h at 1 mA cm^(-2)/1 mAh cm^(-2))for Znjj Zn battery,as well as high Coulombic efficiency for Znjj Cu battery(averagely 99.14%within 439 cycles at 1 mA cm^(-2)/1 mAh cm^(-2)).The assembled Znjj NH_(4)V_(4)O_(10)battery delivers a high reversible specific capacity of 328.5 mAh g^(-1)at 0.1 A g^(-1).Moreover,the device of Znjj NH_(4)V_(4)O_(10)pouch battery remains operational under severe conditions like bending and cutting.This work provides valuable reference in developing inorganic nanoparticle hybrid hydrogel electrolyte for realizing high-performance zinc metal batteries.
文摘This study prepared and characterized amphiphilic carboxymethyl cellulose stearate(CMCS)recycled from sugarcane bagasse agro-waste(SB).The Fourier-transform infrared(FTIR)analysis confirmed cellulose,carboxymethyl cellulose(CMC),and CMCS structures,with CMCS showing increased H-bonding.X-ray diffraction analysis(XRD)revealed reduced crystallinity in CMC and CMCS.CMCS exhibited a hydrophobic nature but dispersed in water,enabling nanoemulsion formation.Optimal nanoemulsion was achieved with CMCS1,showing a particle size of 99 nm.Transmission electron microscopy(TEM)images revealed CMC’s honeycomb structure,transforming into spherical particles in CMCS1.Antimicrobial tests demonstrated strong activity of CMCS formulations against Escherichia coli and Staphylococcus aureus,with CMCS3 exhibiting the highest efficacy.These findings highlight the potential of CMCS-based nanoemulsions for antimicrobial applications and nanoemulsification.
文摘Biodegradable packaging has emerged as a viable alternative to non-biodegradable polymers.This study explores different treatments of agar-carboxymethyl cellulose(CMC)nanocomposites developed via the casting method.We investigated the effects of varying glycerol levels(20%-60%)as a plasticizer and nanocellulose levels(0%-30%)as a filler on the properties of agar-CMC nanocomposites.Key properties analyzed included water vapor permeability,solubility in water,moisture absorption,water contact angle,color properties,and mechanical properties.The films exhibited low water vapor permeability,ranging from 2.50×10^(-11) g/msPa to 2.23×10^(-12) g/msPa.Water solubility of the films was below 40%,except for the film containing 60%glycerol.Despite this,all samples demonstrated very low moisture absorption.The water droplet contact angle tests indicated that the film surfaces were moderately hydrophilic.Increasing the nanocellulose content further enhanced the hydrophilicity of the surfaces.The maximum tensile strength and elongation at break recorded were 31.09 MPa and 46.2%,respectively.While adding glycerol reduced tensile strength,it improved elongation at break.Visual observations and color evaluation revealed that the films were transparent,with a low total color difference and a low yellow index.The simultaneous use of both agar and carboxymethyl cellulose polymers in biocomposite formulation successfully mitigated the disadvantages associated with each biopolymer when used alone,thereby enhancing their functional properties.
基金supported by the National Research Foundation(NRF)of Korea grant funded by the Korean government(MSIT)(No.NRF-2021 M3 H4A1A02045962).
文摘With the increasing prevalence of lithium-ion batteries(LIBs)applications,the demand for high-capacity next-generation materials has also increased.SiO_(x)is currently considered a promising anode material due to its exceptionally high capacity for LIBs.However,the significant volumetric changes of SiO_(x)during cycling and its initial Coulombic efficiency(ICE)complicate its use,whether alone or in combination with graphite materials.In this study,a three-dimensional conductive binder network with high electronic conductivity and robust elasticity for graphite/SiO_(x)blended anodes was proposed by chemically anchoring carbon nanotubes and carboxymethyl cellulose binders using tannic acid as a chemical cross-linker.In addition,a dehydrogenation-based prelithiation strategy employing lithium hydride was utilized to enhance the ICE of SiO_(x).The combination of these two strategies increased the CE of SiO_(x)from 74%to87%and effectively mitigated its volume expansion in the graphite/SiO_(x)blended electrode,resulting in an efficient electron-conductive binder network.This led to a remarkable capacity retention of 94%after30 cycles,even under challenging conditions,with a high capacity of 550 mA h g^(-1)and a current density of 4 mA cm^(-2).Furthermore,to validate the feasibility of utilizing prelithiated SiO_(x)anode materials and the conductive binder network in LIBs,a full cell incorporating these materials and a single-crystalline Ni-rich cathode was used.This cell demonstrated a~27.3%increase in discharge capacity of the first cycle(~185.7 mA h g^(-1))and exhibited a cycling stability of 300 cycles.Thus,this study reports a simple,feasible,and insightful method for designing high-performance LIB electrodes.
基金supported by the National Key Research and Development Program of China(No.2020YFC1808701)the Fundamental Research Funds for the Central Universities(No.buctrc202232).
文摘Nano zero-valent iron(nZVI)is widely used in soil remediation due to its high reactivity.However,the easy agglomeration,poor antioxidant ability and passivation layer of Fe-Cr coprecipitates of nZVI have limited its application scale in Cr-contaminated soil remediation,especially in high concentration of Cr-contaminated soil.Herein,we found that the carboxymethyl cellulose on nZVI particles could increase the zeta potential value of soil and change the phase of nZVI.Along with the presence of biochar,97.0%and 96.6%Cr immobilization efficiency through CMC-nZVI/BC were respectively achieved in high and low concentrations of Cr-contaminated soils after 90-days remediation.In addition,the immobilization efficiency of Cr(VI)only decreased by 5.1%through CMC-nZVI/BC treatment after 10 weeks aging in air,attributing to the strong antioxidation ability.As for the surrounding Crcontaminated groundwater,the Cr(VI)removal capacity of CMC-nZVI/BC was evaluated under different reaction conditions through column experiments and COMSOL Multiphysics.CMC-nZVI/BC could efficiently remove 85%of Cr(VI)in about 400 hr when the initial Cr(VI)concentration was 40 mg/L and the flow rate was 0.5 mL/min.This study demonstrates that uniformly dispersed CMC-nZVI/BC has an excellent remediation effect on different concentrations of Cr-contaminated soils.
基金supported by the National Key Research and Development Program(2021YFB3501103)Guiding Local Funding Projects for Scientific and Technological Development by Central Government in Hebei(216Z1402G)Youth Fund of GRINM Group Co.,Ltd.
文摘The lanthanum-cerium-based slurry(LC-slurry)is extensively utilized in the chemical mechanical polishing(CMP)of TFT-LCD glass substrates,optical lenses,and other glass products.Sodium hexametaphosphate(SHMP),as a dispersant,is commonly employed to enhance the dispersion properties of LCslurry for improved polishing performance.However,the tendency of sedimentation to form a compacted sediment layer,which is challenging to redisperse,increases storage difficulty and polishing equipment failure risk,thereby limiting its utilization in CMP.In the present study,sodium carboxymethylcellulose(CMC-Na),a long-chain organic polymer,was employed to enhance the redispersibility of LC-slurry containing SHMP.A comprehensive investigation was conducted on the influence of CMC-Na dosage and slurry pH on dispersibility,redispersibility and polishing performance.Additionally,an analysis was carried out to elucidate the underlying mechanism behind the effect of CMC-Na.The study demonstrates that the LC-slurry,containing 250 ppm SHMP and 500 ppm CMC-Na,exhibits excellent dispersibility and redispersibility.Further polishing tests demonstrate that compared to the LC-slurry containing only SHMP,utilizing the slurry containing both SHMP and CMC-Na at various pH for polishing thin film transistor liquid crystal display(TFT-LCD)glass substrates results in a reduction of both material removal rate(MRR)and surface roughness(Sa).Specifically,when adjusting the slurry to a pH range of 5-6,the MRR can reach up to 330 nm/min,which closely approximates the MRR achieved by LC-slurry containing only 250 ppm SHMP at corresponding pH values.Meanwhile,after polishing,the surface roughness of the glass substrate measures approximately 0.47 nm.
文摘The management of chronic wounds remains a substantial challenge for healthcare providers. Inadequate wound care can result in serious complications, including infection, which may ultimately lead to amputation or even death. While traditional excipients exhibit some efficacy in promoting wound healing, they are not sufficiently effective in preventing wound infections. As an antimicrobial metal, copper has a long history in the antimicrobial field, and at the same time, wound auxiliaries with copper ions have also been used in the treatment of chronic wounds. To address the limitations of conventional wound dressings, including insufficient antimicrobial properties and limited capacity to promote wound healing, this study introduces a highly adhesive hydrogel with superior mechanical stability for non-invasive wound treatment. The hydrogel was composed of carboxymethyl chitosan, tannic acid and copper ions. The tannic acid solution was subjected to dropwise addition of CuCl2 solution to produce precipitation, and tannic acid/copper ions (TA/Cu2+) composite nanoparticles were prepared. Through topological adhesion, the CMCS with pH sensitivity has the ability to establish adhesive connections with a wide range of materials. The benefits of CMCS/TA/Cu2+ hydrogel, as a kind of wound closure and repair material, include efficient wound closure, and resistance against bacterial invasion while maintaining cleanliness. Additionally, it exhibits excellent tensile and mechanical stability that can facilitate effective closure and repair in dynamic areas like joint wounds. This promising hydrogel adhesive has demonstrated potential as a material for wound closure and restoration.
基金Projects (50804055,50974134) supported by the National Natural Science Foundation of ChinaProject (09JJ3100) supported by the Natural Science Foundation of Hunan Province,China
文摘Carboxymethyl starchs（CMS） with low and high degrees of substitution（CMSL and CMSH in short,respectively） were employed as depressants of diaspore in cationic reverse flotation using dodecylamine（DDA） as collector.The effect of degree of substitution of CMS on its depression performance was examined and the interaction mode and behavior were investigated in a comparative manner.Micro-flotation test showed that CMSL exhibited better performance in depressing diaspore than CMSH in a broad pH range.The adsorption of CMS on diaspore was studied by adsorption test,zeta potential measurement,and atomic force microscopy.It was found that CMSH corresponds to lower adsorption amount,thinner adsorption layer,and more negative charge than CMSL,resulting from the more chelating sites brought by the high degree of substitution.The surface tension measurement and DDA adsorption test further revealed that CMSL/DDA system gives a better depressing performance benefiting from the trapping effect by enveloping some DDA molecules inside the loop chains,while CMSH/DDA system is likely considered a quasi-surfactant.
基金Supported by Shanghai Leading Academic Discipline(Project No.T1102)Shanghai Commission of Education Scientific Research Project(07zz134)~~
文摘[Objective] In order to study the relations among different positions, degrees of substitution and antioxidant ability. [Method] N, O-carboxymethyl chitosan （NOA, NOB and NOC）with various degrees of substitution （DS）were obtained by etherizing chito-oligosacchaside. Their structure and substituted degree were characterized and their antioxldant activity to·OH was evaluated. [ Result] The IC50 s of NOA ,NOB and NOC were 0.15 ,0. 29 ,0. 23 mg/ml while their DSs of -NH2 position（DSN） were 0.51,0.29 and 0.38 and DSo were 0. 74 ,0. 84 ,0. 97respectively.[ Conclusion] With the increase of DSN ,antioxidant activity of N,O-carboxymethyl chitosan oligosaccharide to·OH was up.
基金Project(51174229) supported by the National Natural Science Foundation of China
文摘The effects of copper ions and calcium ions on the depression of chlorite using CMC（carboxymethyl cellulose） as a depressant were studied through flotation tests,adsorption measurements,ζ potential tests and co-precipitation experiments.The results show that the electrostatic repulsion between the CMC molecules and the chlorite surfaces hinders the approach of the CMC to the chlorite while the presence of copper ions and calcium ions enhances the adsorption density of CMC.The action mechanisms of these two types of ions are different.Calcium ions can not adsorb onto the mineral surfaces,but they can interact with the CMC molecules,thus reducing the charge of the CMC and enhancing adsorption density.Copper ions can adsorb onto the mineral surfaces,which facilitates the CMC adsorption through acid/base interaction.The enhanced adsorption density is also attributed to the decreased electrostatic repulsion between the CMC and mineral surfaces as copper ions reduce the surface charge of both the mineral surfaces and the CMC molecules.
基金This work was supported by the National Natural Science Foundation of China (No. 20074025), the Area of Excellence(AoE) on Plant and Fungal Biotechnology Project of the Hong Kong SAR Government and Key Laboratory of Cellulose andLignocellulosic Chemistry of Chinese Academy of Sciences.
文摘A new solvent of cellulose (1.5 mol/L NaOH/0.5 mol/L urea aqueous solution) was used as one of the homogeneous reaction media of polysaccharides for methylation, hydroxyethylation and hydroxypropylation. A water insoluble β -(1—>3)-D-glucan, sample PCS3- isolated from fresh sclerotium of Poria cocos was sulfated in dimethyl sulfoxide (Me 2 SO), carboxymethylated in NaOH, isopropanol solution, as well as methylated, hydroxyethylated and hydroxypropylated in the new solvent system, respectively, to obtain five water-soluble derivatives coded as S-PCS3- C- PCS3- M-PCS3- HE-PCS3- and HP-PCS3- Their chemical structure and distribution of substitution were characterized by infrared spectroscopy (IR), elementary analysis (EA), 1 H-NMR, 13 C-NMR, 2D-COSY, 2D-TOCSY and 2D- 1 H-detected 1H 13C HMQC spectra. The results reveal that the relative reactivity of hydroxyl groups of the β -(1-?3)-D-glucan is in the order C-6 > C-4 > C-2 on the whole. The substitution of the samples S-PCS3- C-PCS3- and M-PCS3- occurred mainly at C-6 position and secondly at C-4 and C-2 positions, and that of HE-PCS3- occurred at C-6 and C-4 positions and of HP-PCS3- almost completely occurred at C-6 position. The degrees of substitution (DS) obtained from 13 C-NMR range from 0.23 to 1.27. The water solubility of the derivatives is in the order S-PCS3- >C-PCS3- >M-PCS3- >HE-PCS3- >HP-PCS3- This work provides a novel and nonpolluting process for the methylation, hydroxyethylation and hydroxypropylation of β -(1—>3)-D-glucan.
基金Supported by "Twelfth Five-Year" National Science and Technology Support Project of China(2012BAK01B03)National 863 Plan(2013AA102202)~~
文摘Advanced glycation end-products （AGEs） are products of non-enzymatic glycation of proteins, lipids or nucleic acids and other macromolecules. To be spe- cific, Nε-（carboxymethyl）-Iysine （CML） is one of the most important components of AGEs, which is wildly distributed in the body and can be formed in vivo or in food processing and heating processes. Previous studies have shown that CML is a ma- jor immunological epitope in AGEs and plays an important role in diabetes and its complications, as well as in the development and progression of aging. This review summarized recent advances in major source, toxicological hazard and control mea- sures of CML.
文摘A linear alpha -D-(1-->3)-glucan, named PSG, was obtained from the spores of Ganoderma lucidum. The synthesis of positively and negatively charged polyelectrolytes from PSG was developed. Amine groups and carboxymethyl groups were introduced through nucleophilic substitution with 3-chloropropylamine or chloroacetic acid, respectively, Reaction conditions were varied to obtain insight into the influence of variables on the degree of substitution.
基金Higher Education Research Promotion-National Research Universities (HERP-NRU) for financial supporting under grant no. 2558A10862016
文摘Crude seed gum and their carboxymethyl derivatives from Tamarindus indica and Cassia fistula seeds were developed and characterized to apply as the pharmaceutical disintegrant in fast disintegrating Thai cordial tablet. The chemical structure of crude gum was chemically modified via carboxymethylation. Degree of substitution(DS) of carboxymethylated gums was determined. Carboxymethylated gums with minimum and maximum DS values were chosen for further application. IR absorption spectra of gum samples were observed to verify their chemical structure changes. In physical properties, the intrinsic viscosity and swelling property of all gum samples were evaluated. The results showed that carboxymethylated gums had higher intrinsic viscosity than those of crude gum. Moreover, they could swell and be soluble in cold water better than those of crude gums. In conclusion, the modified gums from both plants could provide higher hardness and be better used than that crude gums for fast disintegrating Thai cordial tablet. However, this is a preliminary assessment to expressing pharmaceutical application possibility of these gums as disintegrants, diluents and drug release controlling agents.
