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
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
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
Poria cocos(PC)is a famous traditional Chinese medicine(TCM)and a widely used healthcare ingredient,which has antiobesity,enhancing immunity and improving sleep effects.Traditionally,only water-soluble poria polysacch...Poria cocos(PC)is a famous traditional Chinese medicine(TCM)and a widely used healthcare ingredient,which has antiobesity,enhancing immunity and improving sleep effects.Traditionally,only water-soluble poria polysaccharide(WSP)is extracted and applied for clinical application,while insoluble polysaccharide(alkali-soluble poria polysaccharide,ASP)is discarded as herb residue.However,the whole PC has also been historically utilized as functional herbal food.Considering the beneficial role of dietary fiber and the traditional use of PC,ASP may also contribute substantially to the therapy function of PC.Compared to WSP,little attention has been paid to ASP and ASP modified product carboxymethyl poria polysaccharide(CMP)which has been used as an antitumor adjuvant drug.In this study,the oil,cholesterol,metal ions and polyphenols adsorption ability,in vitro simulated digestive and the gut microbiota fermentation characteristics of WSP,ASP and CMP were studied to evaluate the functional values of three P.cocos polysaccharides(PCPs).The results showed that all three PCPs had good adsorption capacity on cholesterol,polyphenols and metal ions(Cd^(2+)/Zn^(2+)/Mg^(2+)),among which ASP showed the highest capacity than WSP and CMP.The adsorption capacity of all three PCPs on heavy metal ions(Cd^(2+)/Zn^(2+))was stronger than that of non-heavy metal ions(Mg^(2+));The in vitro digestibility of all three PCPs was very low,but WSP was slightly higher than ASP and CMP;Moreover,the indigestible residue of all three PCPs could improve the richness and diversity of gut microbiota,among which ASP had the greatest influence.In general,ASP and CMP could significantly promote the proliferation of some probiotics and inhibit the growth of some harmful bacteria.The gut microbiota diversity of CMP was reduced,but the richness of probiotics,especially Parabacteroides distasonis was significantly enhanced compared with the ASP group,and the growth of harmful bacteria Klebsiella pneumoniae was inhibited after CMP treatment.The short-chain fatty acids(SCFAs)analysis results showed that all three PCPs could significantly promote the production of acetic acid,propionic acid and the total acid content compared with blank control group,and SCFAs producing activity was positively correlated with the proliferative capacity of probiotics.Taken together,the good adsorption characteristics and gut microbiota regulatory activity of ASP may lay foundation for its lipid-lowering and immune-improving function.Additionally,the probiotic effect of CMP and ASP indicated that except for only use the water extract of PC in clinic,CMP and ASP also can be used in healthcare to take full advantage of this valuable medicine.展开更多
Internal curing agents (ICA) based on super absorbent polymer have poor alkali tolerance and reduce the early strength of concrete.An alkali tolerate internal curing agent (CAA-ICA) was designed and prepared by using ...Internal curing agents (ICA) based on super absorbent polymer have poor alkali tolerance and reduce the early strength of concrete.An alkali tolerate internal curing agent (CAA-ICA) was designed and prepared by using sodium carboxymethyl starch (CMS) with high hydrophilicity,acrylic acid (AA) containing anionic carboxylic group and acrylamide (AM) containing non-ionic amide group as the main raw materials.The results show that the ratio of CAA-ICA alkali absorption solution is higher than that existing ICA,which solves the low water absorption ratio of the ICA in alkali environment.The water absorption ratio of CAA-ICA in saturated Ca(OH)_(2) solution is 95.8 g·g^(-1),and the alkali tolerance coefficient is 3.4.The application of CAA-ICA in cement-based materials can increase the internal relative humidity and miniaturize the pore structure.The compressive strength of mortar increases up to 12.95%at 28 d,which provids a solution to overcome the reduction of the early strength.展开更多
Diabetes-associated cognitive dysfunction has already been attracted considerable attention.Advanced glycation end products(AGEs)from daily diets are thought to be a vital contributor to the development of this diseas...Diabetes-associated cognitive dysfunction has already been attracted considerable attention.Advanced glycation end products(AGEs)from daily diets are thought to be a vital contributor to the development of this diseases.However,the effect of one of the best-characterized exogenous AGEs N^(ε)-(carboxymethyl)lysine(CML)on cognitive function is not fully reported.In the present study,diabetical Goto-Kakizaki(GK)rats were treated with free CML for 8-weeks.It was found that oral consumption of exogenous CML significantly aggravated diabetes-associated cognitive dysfunction in behavioral test.In details,exogenous CML increased levels of oxidative stress,promoted the activation of glial cells in the brain,up-regulated the release of inflammatory cytokines interleukin-6,inhibited the protein expression of the brain-derived neurotrophic factor and thus led to neuroinflammation.Furthermore,exogenous CML promoted the amyloidogenesis in the brain of GK rats,and inhibited the expression of GLUT4.Additionally,several tricarboxylic acid cycle and glutamate-glutamine/γ-aminobutyric acid cycle intermediates including pyruvate,succinic acid,glutamine,glutamate were significantly changed in brain of GK rats treated with exogenous free CML.In conclusion,exogenous free CML is a potentially noxious compounds led to aggravated diabetes-associated cognitive dysfunction which could be possibly explained by its effects on neuroinflammation,energy and neurotransmitter amino acid homeostasis.展开更多
In this study,intelligent,pH-responsive colorimetric films were prepared by encapsulating anthocyanins in nanocomplexes prepared from glutenin and carboxymethyl chitosan.These nanocomplexes were added to a corn starch...In this study,intelligent,pH-responsive colorimetric films were prepared by encapsulating anthocyanins in nanocomplexes prepared from glutenin and carboxymethyl chitosan.These nanocomplexes were added to a corn starch matrix and used in the freshness monitoring of chilled pork.The effects of anthocyanin-loaded nanocomplexes on the physical,structural,and functional characteristics of the films were investigated.The addition of anthocyanin-loaded nanocomplexes increased the tensile strength,elongation at break,hydrophobicity,and light transmittance of the films while decreasing their water vapor permeability.This is because new hydrogen bonds are formed between the film components,resulting in a more homogeneous and dense structure.The colorimetric film has a significant color response to pH changes.These films were used in experiments on the freshness of chilled pork,in which the pH changes with changing freshness states.The results show that the colorimetric film can monitor changes in the freshness of chilled pork in real time,where orange,pink,and green represent the fresh,secondary fresh,and putrefied states of pork,respectively.Therefore,the intelligent colorimetric film developed in this study has good application potential in the food industry.展开更多
The Thermomyces lanuginosus lipase(TLLs)was successfully immobilized within a novel hydrogel matrix through a two-step crosslinking method.TLLs were initially crosslinked through the Schiff base reaction by oxidized c...The Thermomyces lanuginosus lipase(TLLs)was successfully immobilized within a novel hydrogel matrix through a two-step crosslinking method.TLLs were initially crosslinked through the Schiff base reaction by oxidized carboxymethyl cellulose(OCMC).The water-soluble OCMC@TLLs complex was subsequently crosslinked by carboxymethyl chitosan(CMCSH)in a microfluidic apparatus to form the CMCHS/OCMC@TLLs microspheres.The CD(Circular Dichroism,CD)and FT-IR(Fourier Transform infrared spectroscopy,FT-IR)spectra demonstrated that the crosslinking of TLLs with OCMC resulted in a less significant impact on their structure compared to that with glutaraldehyde.CMCHS/OCMC@TLLs showed decreased catalytic performance due to the mass transfer resistance,while its thermal stability was greatly improved.The CMCHS/OCMC@TLLs were used to catalyze the lauroylation of arbutin in tetrahydrofuran.After 12 h of reaction under optimal conditions,the yield of 6′-O-lauryl arbutin reached an impres-sive 92.12%.The prepared 6′-O-lauryl arbutin has high lipophilicity and exhibits similar tyrosinase inhibitory activity and higher antioxidant activity compared to its parent compound.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
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.
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.
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supported by the Province Natural Science Foundation of Hunan,China (2022JJ5410)Special Project on Modern Agricultural Industrial Technology System Construction of Hunan,China (2022-67)。
文摘Poria cocos(PC)is a famous traditional Chinese medicine(TCM)and a widely used healthcare ingredient,which has antiobesity,enhancing immunity and improving sleep effects.Traditionally,only water-soluble poria polysaccharide(WSP)is extracted and applied for clinical application,while insoluble polysaccharide(alkali-soluble poria polysaccharide,ASP)is discarded as herb residue.However,the whole PC has also been historically utilized as functional herbal food.Considering the beneficial role of dietary fiber and the traditional use of PC,ASP may also contribute substantially to the therapy function of PC.Compared to WSP,little attention has been paid to ASP and ASP modified product carboxymethyl poria polysaccharide(CMP)which has been used as an antitumor adjuvant drug.In this study,the oil,cholesterol,metal ions and polyphenols adsorption ability,in vitro simulated digestive and the gut microbiota fermentation characteristics of WSP,ASP and CMP were studied to evaluate the functional values of three P.cocos polysaccharides(PCPs).The results showed that all three PCPs had good adsorption capacity on cholesterol,polyphenols and metal ions(Cd^(2+)/Zn^(2+)/Mg^(2+)),among which ASP showed the highest capacity than WSP and CMP.The adsorption capacity of all three PCPs on heavy metal ions(Cd^(2+)/Zn^(2+))was stronger than that of non-heavy metal ions(Mg^(2+));The in vitro digestibility of all three PCPs was very low,but WSP was slightly higher than ASP and CMP;Moreover,the indigestible residue of all three PCPs could improve the richness and diversity of gut microbiota,among which ASP had the greatest influence.In general,ASP and CMP could significantly promote the proliferation of some probiotics and inhibit the growth of some harmful bacteria.The gut microbiota diversity of CMP was reduced,but the richness of probiotics,especially Parabacteroides distasonis was significantly enhanced compared with the ASP group,and the growth of harmful bacteria Klebsiella pneumoniae was inhibited after CMP treatment.The short-chain fatty acids(SCFAs)analysis results showed that all three PCPs could significantly promote the production of acetic acid,propionic acid and the total acid content compared with blank control group,and SCFAs producing activity was positively correlated with the proliferative capacity of probiotics.Taken together,the good adsorption characteristics and gut microbiota regulatory activity of ASP may lay foundation for its lipid-lowering and immune-improving function.Additionally,the probiotic effect of CMP and ASP indicated that except for only use the water extract of PC in clinic,CMP and ASP also can be used in healthcare to take full advantage of this valuable medicine.
基金Funded by the National Key Research and Development Program of China (No.2019YFC1906202)the Guangxi Key Research and Development Plan (Nos.Guike AA18242007-3, Guike AB19259008, and Guike AB20297014)。
文摘Internal curing agents (ICA) based on super absorbent polymer have poor alkali tolerance and reduce the early strength of concrete.An alkali tolerate internal curing agent (CAA-ICA) was designed and prepared by using sodium carboxymethyl starch (CMS) with high hydrophilicity,acrylic acid (AA) containing anionic carboxylic group and acrylamide (AM) containing non-ionic amide group as the main raw materials.The results show that the ratio of CAA-ICA alkali absorption solution is higher than that existing ICA,which solves the low water absorption ratio of the ICA in alkali environment.The water absorption ratio of CAA-ICA in saturated Ca(OH)_(2) solution is 95.8 g·g^(-1),and the alkali tolerance coefficient is 3.4.The application of CAA-ICA in cement-based materials can increase the internal relative humidity and miniaturize the pore structure.The compressive strength of mortar increases up to 12.95%at 28 d,which provids a solution to overcome the reduction of the early strength.
基金supported by the National Natural Science Foundation of China(32302258,32172317)Changsha Municipal Natural Science Foundation(kq2202223).
文摘Diabetes-associated cognitive dysfunction has already been attracted considerable attention.Advanced glycation end products(AGEs)from daily diets are thought to be a vital contributor to the development of this diseases.However,the effect of one of the best-characterized exogenous AGEs N^(ε)-(carboxymethyl)lysine(CML)on cognitive function is not fully reported.In the present study,diabetical Goto-Kakizaki(GK)rats were treated with free CML for 8-weeks.It was found that oral consumption of exogenous CML significantly aggravated diabetes-associated cognitive dysfunction in behavioral test.In details,exogenous CML increased levels of oxidative stress,promoted the activation of glial cells in the brain,up-regulated the release of inflammatory cytokines interleukin-6,inhibited the protein expression of the brain-derived neurotrophic factor and thus led to neuroinflammation.Furthermore,exogenous CML promoted the amyloidogenesis in the brain of GK rats,and inhibited the expression of GLUT4.Additionally,several tricarboxylic acid cycle and glutamate-glutamine/γ-aminobutyric acid cycle intermediates including pyruvate,succinic acid,glutamine,glutamate were significantly changed in brain of GK rats treated with exogenous free CML.In conclusion,exogenous free CML is a potentially noxious compounds led to aggravated diabetes-associated cognitive dysfunction which could be possibly explained by its effects on neuroinflammation,energy and neurotransmitter amino acid homeostasis.
基金funded by the Hainan Provincial Natural Science Foundation of China[Grant Number 2019RC031]National Natural Science Foundation of China[Grant Number 31460407].
文摘In this study,intelligent,pH-responsive colorimetric films were prepared by encapsulating anthocyanins in nanocomplexes prepared from glutenin and carboxymethyl chitosan.These nanocomplexes were added to a corn starch matrix and used in the freshness monitoring of chilled pork.The effects of anthocyanin-loaded nanocomplexes on the physical,structural,and functional characteristics of the films were investigated.The addition of anthocyanin-loaded nanocomplexes increased the tensile strength,elongation at break,hydrophobicity,and light transmittance of the films while decreasing their water vapor permeability.This is because new hydrogen bonds are formed between the film components,resulting in a more homogeneous and dense structure.The colorimetric film has a significant color response to pH changes.These films were used in experiments on the freshness of chilled pork,in which the pH changes with changing freshness states.The results show that the colorimetric film can monitor changes in the freshness of chilled pork in real time,where orange,pink,and green represent the fresh,secondary fresh,and putrefied states of pork,respectively.Therefore,the intelligent colorimetric film developed in this study has good application potential in the food industry.
基金supported by the Youth Foundation of Southeast University ChengXian College(z0055).
文摘The Thermomyces lanuginosus lipase(TLLs)was successfully immobilized within a novel hydrogel matrix through a two-step crosslinking method.TLLs were initially crosslinked through the Schiff base reaction by oxidized carboxymethyl cellulose(OCMC).The water-soluble OCMC@TLLs complex was subsequently crosslinked by carboxymethyl chitosan(CMCSH)in a microfluidic apparatus to form the CMCHS/OCMC@TLLs microspheres.The CD(Circular Dichroism,CD)and FT-IR(Fourier Transform infrared spectroscopy,FT-IR)spectra demonstrated that the crosslinking of TLLs with OCMC resulted in a less significant impact on their structure compared to that with glutaraldehyde.CMCHS/OCMC@TLLs showed decreased catalytic performance due to the mass transfer resistance,while its thermal stability was greatly improved.The CMCHS/OCMC@TLLs were used to catalyze the lauroylation of arbutin in tetrahydrofuran.After 12 h of reaction under optimal conditions,the yield of 6′-O-lauryl arbutin reached an impres-sive 92.12%.The prepared 6′-O-lauryl arbutin has high lipophilicity and exhibits similar tyrosinase inhibitory activity and higher antioxidant activity compared to its parent compound.
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.
