The development of pollution-free dyeing technology, including anhydrous dyeing and non-aqueous dyeing technologies, has always been an important way and research hot in energy conservation and emission reduction. Des...The development of pollution-free dyeing technology, including anhydrous dyeing and non-aqueous dyeing technologies, has always been an important way and research hot in energy conservation and emission reduction. Designing new structural dye molecules is the key to water-saving dyeing processes.Herein, three reactive dyes were designed and synthesized, which contained large planar multiconjugated systems and multi-reactive groups. The designed reactive dyes are expected to have high affinity and high fixations in non-aqueous or small bath dyeing processes. The reactive dyes were applied in the decamethylcyclopentasiloxane(DMCS) reverse micelle dyeing for cotton fabric. High exhaustion rate of 99.35%, 98.10% and 98.80%, and fixation rate of 95.15%, 96.34% and 94.40% for three dyes, R1,R2 and R3, could be respectively obtained. The dyes can be fully utilized and had excellent dyeing performance, fastness and levelling properties under the revere micelle dyeing. The cotton fabric is like an oil-water separator in the dyeing process, where the dye micelles rapidly absorb and permeate into the cotton fibers. DMCS circulates around the fabric to transfer mass and energy. After dyeing, the solvent can be separated quickly and reused. The new reactive dyes containing large planar and multi-conjugated systems have potential application in green and sustainable dyeing technology with less wastewater and higher utilization.展开更多
The scenario of geothermal tunnel is commonly observed around the world,and increases with the new constructions in the long and deep tunnels,for example in China.Tunnel insulation is generally divided into active and...The scenario of geothermal tunnel is commonly observed around the world,and increases with the new constructions in the long and deep tunnels,for example in China.Tunnel insulation is generally divided into active and passive insulation.In passive insulation,it is an effective way to set low thermal con-ductivity materials as the thermal insulation layer as the choice of insulation material mainly depends on the thermal conductivity.Polymer is a kind of material with good geothermal performance,but there are relatively few studies.In this context,the transient plane source(TPS)method was used to measure the thermal conductivity of the developed polymer.Then,the temperature field of the high geothermal tunnel insulated by the non-aqueous reactive polymer layer was simulated.With the parametric analysis results,the suggestions for the tunnel layers were proposed accordingly.It revealed that the thermal conductivity of polymer first increases and then decreases with temperature.There are two rising sec-tions(?40e10?C and 20e90?C),one flat section(10e20?C)and one descending section(>90?C).It is observed the thermal conductivity of polymer increases with increase of the density of insulation layer and the density,and the thermal conductivity decreases when exposed to high temperatures.The temperature of the surrounding rocks increases with increase of the thermal conductivity and the thickness of polymer.Finally,a more economical thickness(5 cm)was proposed.Based on the parametric study,a thermal insulation layer with thermal conductivity less than 0.045 W/(m K),thickness of 5 cm and a density less than 0.12 g/cm 3 is suggested for practice.展开更多
Flow batteries with high energy density and long cycle life have been pursued to advance the progress of energy storage and grid application. Non-aqueous batteries with wide voltage windows represent a promising techn...Flow batteries with high energy density and long cycle life have been pursued to advance the progress of energy storage and grid application. Non-aqueous batteries with wide voltage windows represent a promising technology without the limitation of water electrolysis, but they suffer from low electrolyte concentration and unsatisfactory battery performance. Here, a non-aqueous lithium bromine rechargeable battery is proposed, which is based on Br_2/Br^-and Li^+/Li as active redox pairs, with fast redox kinetics and good stability. The Li/Br battery combines the advantages of high output voltage(~3.1 V),electrolyte concentration(3.0 mol/L), maximum power density(29.1 m W/cm^2) and practical energy density(232.6 Wh/kg). Additionally, the battery displays a columbic efficiency(CE) of 90.0%, a voltage efficiency(VE) of 88.0% and an energy efficiency(EE) of 80.0% at 1.0 m A/cm^2 after continuously running for more than 1000 cycles, which is by far the longest cycle life reported for non-aqueous flow batteries.展开更多
The demands for high-performance and low-cost batteries make K-ion batteries(KIBs) considered as promising supplements or alternatives for Li-ion batteries(LIBs). Nevertheless, there are only a small amount of convent...The demands for high-performance and low-cost batteries make K-ion batteries(KIBs) considered as promising supplements or alternatives for Li-ion batteries(LIBs). Nevertheless, there are only a small amount of conventional inorganic electrode materials that can be used in KIBs, due to the large radius of K^+ ions. Diff erently, organic electrode materials(OEMs) generally own sufficiently interstitial space and good structure flexibility, which can maintain superior performance in K-ion systems. Therefore, in recent years, more and more investigations have been focused on OEMs for KIBs. This review will comprehensively cover the researches on OEMs in KIBs in order to accelerate the research and development of KIBs. The reaction mechanism, electrochemical behavior, etc., of OEMs will all be summarized in detail and deeply. Emphasis is placed to overview the performance improvement strategies of OEMs and the characteristic superiority of OEMs in KIBs compared with LIBs and Na-ion batteries.展开更多
Unilamellar vesicles from the mixtures of 1:1 sodium 10-undecenoate and trimethyl[2-(10-undecenoyloxy) ethyl]ammonium iodide in the mixed solvents of ethanol and heptane can be formed spontaneously or by sonication. T...Unilamellar vesicles from the mixtures of 1:1 sodium 10-undecenoate and trimethyl[2-(10-undecenoyloxy) ethyl]ammonium iodide in the mixed solvents of ethanol and heptane can be formed spontaneously or by sonication. They can ekist in the variation of concentrations and volume ratios of ethanol to heptane. Which indicates to some extent the high capability of vesicle formation in such mixed展开更多
Polyoxometalates have been explored as multi-electron active species in both aqueous and non-aqueous redox flow batteries. Although non-aqueous systems in principle offer a wider voltage window for redox flow battery ...Polyoxometalates have been explored as multi-electron active species in both aqueous and non-aqueous redox flow batteries. Although non-aqueous systems in principle offer a wider voltage window for redox flow battery operation, realization of this potential requires a judicious choice of solvent as well as polyoxometalate properties. We demonstrate here the superior performance of N,N-dimethylformamide(DMF)compared to acetonitrile as a solvent for redox flow batteries based on Li3PMo12O40. This compound displays two 1-electron transfers in acetonitrile but can access an extra quasi-reversible 2-electron redox process in DMF. A cell containing 10 mM solution of Li3PMo12O40 in DMF produced a cell voltage of 0.7 V with 2-electron transfers(State of Charge = 60%) and showed a good cyclability. As a means to boost energy density, operation of the redox flow battery at a higher concentration of 0.1 M Li3PMo12O40 produced cells with cell voltage of 0.6 V in acetonitrile and a cell voltage of 1.0 V in DMF;both showed excellent coulombic efficiencies of more than 90% over the course of 30 cycles. Energy density was also increased by employing an asymmetric cell with different polyoxometalates on each side to extend cell voltage.Li6P2W18O62 exhibited 3 quasi-reversible 2-electron transfers in the potential range between-2.05 V and-0.5 V vs. Ag/Ag+. 10 mM Li6P2W18O62/Li3PMo12O40 in DMF produced a cell with cell voltage of 1.3 V involving 4-electron transfers(State of Charge = 50%) with coulombic efficiency of nearly 100% and energy efficiency of nearly 70% throughout the test with more than 20 cycles. These promising results demonstrate proof-of-concept approaches to improving the performance of polyoxometalates in non-aqueous redox flow batteries.展开更多
Standard free energies (ΔG0t(i) ) and entropies (ΔS0t(i)) of transfer of some homologous α-amino acids viz. glycine (gly), dl-alanine (ala), dl-α-amino butyric acid (aba) and dl-nor-valine (nor-val) from protic et...Standard free energies (ΔG0t(i) ) and entropies (ΔS0t(i)) of transfer of some homologous α-amino acids viz. glycine (gly), dl-alanine (ala), dl-α-amino butyric acid (aba) and dl-nor-valine (nor-val) from protic ethylene glycol (EG) to dipolar aprotic N,N-dimethyl formamide (DMF) have been evaluated from solubility measure-ments at five equidistant temperatures i.e from 15 to 350C. The observed ΔG0t(i) and TΔS0t(i) Vs composition profiles are complicated because of the various interaction effects. The chemical effects of the transfer Gibbs energies (ΔG0t.ch(i)) and entropies of transfer (ΔS0t.ch(i)) have been obtained after elimination of cavity effect, estimated by the scaled particle theory and dipole-dipole interaction effects, estimated by the use of Keesom-orientation expression. The chemical contributions of transfer energetics of homologous α-amino acids are guided by the composite effects of increased dispersion interaction, basicity and decreased acidity, hydrogen bonding effects and solvophobic solvation of ethylene glycol and N, N-dimethyl formamide mixed solvent as compared to that of reference solvent (ethylene glycol).展开更多
The exploitation of high performance redox-active substances is critically important for the development of non-aqueous redoxflow batteries.Herein,three tetrathiofulvalene(TTF)derivatives with different substitution gr...The exploitation of high performance redox-active substances is critically important for the development of non-aqueous redoxflow batteries.Herein,three tetrathiofulvalene(TTF)derivatives with different substitution groups,namely TTF diethyl ester(TTFDE),TTF tetramethyl ester(TTFTM),and TTF tetraethyl ester(TTFTE),are prepared and their energy storage properties are evaluated.It has been found that the redox potential and solubility of these TTF derivatives in conventional carbonate electrolytes increases with the number of ester groups.The battery with a catholyte of 0.2 mol L^(-1) of TTFTE delivers a specific capacity of more than 10 Ah L^(-1) at the current density of 0.5 C with two discharge voltage platforms locating at as high as 3.85 and 3.60 V vs.Li/Liþ.Its capacity retention can be improved from 2.34 Ah L^(-1) to 3.60 Ah L^(-1) after 100 cycles by the use of an anion exchange membrane to block the crossover of TTF species.The excellent cycling stability of the TIF esters is supported by their well-delocalized electrons,as revealed by the density function theory calculations.Therefore,the introduction of more and larger electron-withdrawing groups is a promising strategy to simultaneously increase the redox-potential and solubility of redox-active ma-terials for non-aqueous redoxflow batteries.展开更多
Three-dimensional investigation of sulfides is required in order to improve the mechanical properties of steel by controlling the sulfides in the steel.A method including its principles and device is introduced for th...Three-dimensional investigation of sulfides is required in order to improve the mechanical properties of steel by controlling the sulfides in the steel.A method including its principles and device is introduced for the investigation of threedimensional morphology of sulfides.The method is suitable for gear steel,free cutting steel,non-quenched steel,tempered steel(ws≥0.02 wt.%),etc.The influences of current density,time,and temperature on the exposure degree of sulfide inclusions were investigated by using 16MnCrS5 steel.The best parameters of electrolytic etching of sulfur steel,as found by experimentation,are as follows:current density,37.5-52.5 mA/cm2;time,30-35 min;and temperature,—10 to 0℃.Under these conditions,the three-dimensional morphology of sulfide inclusions in sulfur-bearing steel can be exposed effectively.展开更多
Nanocrystalline semiconductors are potentially useful materials due to their novel prop-erties which are markedly different from those of the bulk solids,the most notable one beingquantum confinement.Preparation and a...Nanocrystalline semiconductors are potentially useful materials due to their novel prop-erties which are markedly different from those of the bulk solids,the most notable one beingquantum confinement.Preparation and application of nanocrystalline Ⅲ-V class of materialssuch as InP have recently attracted much attention.It is difficult to synthesize Ⅲ-V mat-erials by use of the traditional solid-state methods,due to their high synthesis temper-展开更多
The energy density of non-aqueous carbon-based electrochemical capacitors(cEC)is mainly determined by the specific capacitance and operational voltage range.In this study,we propose to construct an unbalanced structur...The energy density of non-aqueous carbon-based electrochemical capacitors(cEC)is mainly determined by the specific capacitance and operational voltage range.In this study,we propose to construct an unbalanced structure to make full use of stable voltage range for improving energy density.The stable voltage range is firstly carefully explored using cyclic voltammetry.Then an unbalanced carbon-based electrochemical capacitor(ucEC)is constructed with an optimized positive electrode to negative electrode weight ratio and voltage range.Its electrochemical performance is comprehensively investigated,including energy density,power density as well as cycle life.The ucEC is capable to deliver an improved energy density up to 64.9 Wh/kg(1.4 times as high as a general cEC)without sacrificing the power density and cycle life.The electrode properties after cycling are also analyzed,illustrating the change of electrode potential caused by unbalanced structure.The proposed structure demonstrates a great potential for improving the energy density at little cost of electrode design and cell configuration.展开更多
The electrostatic interaction between additive and analyte is of great importance to non-aqueous cap- illary electrophoresis(NACE)separation.Three tetraalkylammonium bromides and acetonitrile were applied as additives...The electrostatic interaction between additive and analyte is of great importance to non-aqueous cap- illary electrophoresis(NACE)separation.Three tetraalkylammonium bromides and acetonitrile were applied as additives and running solvent respectively.The effect of alkyl chain length and concentra- tion of additive on electrostatic interactions was investigated by the separation of phenols.The sepa- ration ability was found to increase with decreasing alkyl chain length of the additive,and the resolu- tion values were increased with increasing additive concentration.The separation was seriously dete- riorated after a little amount of water was added in the running solution.Furthermore,the electrostatic interaction is strong under the conditions of low electron cloud density,weak steric hindrance and multi-interaction sites.Thus,the separation result can be predicted by theoretical analysis,which is helpful for the separation of other substances in NACE based on electrostatic interaction.展开更多
A novel[2]pseudorotaxane of cucurbit[6]uril(CB[6])and 1-butyl-3-methyl-imidazolium bromide([C4mim]Br)was synthesized by directly mixing the host and the guest molecules in non-aqueous system.Structural characteri-zati...A novel[2]pseudorotaxane of cucurbit[6]uril(CB[6])and 1-butyl-3-methyl-imidazolium bromide([C4mim]Br)was synthesized by directly mixing the host and the guest molecules in non-aqueous system.Structural characteri-zations of the[2]pseudorotaxane were carried out by 1D,2D NMR and X-ray crystallography techniques both in solution and in crystal structure.The crystal structure demonstrated that CB[6]and[C4mim]Br formed a complex with the ratio 1∶1,in which one guest[C4mim]Br was included inside the CB[6],while two other[C4mim]Br molecules were free and surrounded the[2]pseudorotaxane as solvent molecules,which could stabilize the crystal structure through hydrogen bonds.Moreover,parallel solvent channels consisting by free[C4mim]Br molecules occupied the pores among the frame of the pseudorotaxanes and formed zigzag lines in the crystal structure.[C4mim]Br can serve as not only the guest reactant but also the solvent in the formation of[2]pseudorotaxane for-mation.展开更多
The instabilities of the battery including cathode corrosion/passivation,shuttling effect of the redox mediators,Li anode corrosion,and electrolyte decomposition are major barriers toward the practical implementation ...The instabilities of the battery including cathode corrosion/passivation,shuttling effect of the redox mediators,Li anode corrosion,and electrolyte decomposition are major barriers toward the practical implementation of lithium-oxygen(Li-O2)batteries.Functional materials offer great potential in high performance Li-O2 batteries owing to their functional tailorability of chemical modification for alleviating side reactions and improving catalysis activity,well-defined properties for discharge products storage,and fast mass and electron transfer paths.In this review,instability problems of non-aqueous Li-O2 batteries and recent studies related to the functional materials in tackling the instability issues from rational cathode construction,inhibition of redox mediators(RMs)shuttling,anode protection and novel electrolyte design are illustrated.Future research directions to overcome the critical issues are also proposed for this promising battery technology.The instability issues and the related strategies with functional materials based on the comprehensive consideration of all battery components proposed in this review provide the systematic,deep understanding and rational design of functional materials for Li-O2 batteries,which is beneficial to achieving the practical Li-O2 batteries.展开更多
Manganese(Mn)doped cadmium sulphide(Cd S)nanoparticles were synthesized using a chemical method.It was possible to decrease Cd S:Mn particle size by increasing Mn concentration.Investigation techniques such as ultravi...Manganese(Mn)doped cadmium sulphide(Cd S)nanoparticles were synthesized using a chemical method.It was possible to decrease Cd S:Mn particle size by increasing Mn concentration.Investigation techniques such as ultraviolet-visible(UV-Vis)absorption spectroscopy and photoluminescence(PL)spectroscopy were used to determine optical properties of Cd S:Mn nanoparticles.Size quantization effect was observed in UV-Vis absorption spectra.Quantum efficiency for luminescence or the internal magnetic field strength was increased by doping Cd S nanoparticles with Mn element.Orange emission was observed at wavelength~630 nm due to ^(4)T_1→^(6)A_1 transition.Isolated Mn~(2+)ions arranged in tetrahedral coordination are mainly responsible for luminescence.Luminescence quenching and the effect of Mn doping on hyperfine interactions in the case of Cd S nanoparticles were also discussed.The corresponding weight percentage of Mn element actually incorporated in doping process was determined by atomic absorption spectroscopy(AAS).Crystallinity was checked and the average size of nanoparticles was estimated using the X-ray diffraction(XRD)technique.Cd S:Mn nanoparticles show ferromagnetism at room temperature.Transmission electron microscopy(TEM)images show spherical clusters of various sizes and selected area electron diffraction(SAED)patterns show the polycrystalline nature of the clusters.The electronic states of diluted magnetic semiconductors(DMS)ofⅡ-Ⅵgroup Cd S nanoparticles give them great potential for applications due to quantum confinement.In this study,experimental results and discussions on these aspects have been given.展开更多
Rechargeable Al batteries(RAB)are promising candidates for safe and environmentally sustainable battery systems with low-cost investments.However,the currently used aluminum chloridebased electrolytes present a signif...Rechargeable Al batteries(RAB)are promising candidates for safe and environmentally sustainable battery systems with low-cost investments.However,the currently used aluminum chloridebased electrolytes present a significant challenge to commercialization due to their corrosive nature.Here,we report for the first time,a novel electrolyte combination for RAB based on aluminum trifluoromethanesulfonate(Al(OTf)_(3))with tetrabutylammonium chloride(TBAC)additive in diglyme.The presence of a mere 0.1 M of TBAC in the Al(OTf)_(3) electrolyte generates the charge carrying electrochemical species,which forms the basis of reaction at the electrodes.TBAC reduces the charge transfer resistance and the surface activation energy at the anode surface and also augments the dissociation of Al(OTf)_(3) to generate the solid electrolyte interphase components.Our electrolyte’s superiority directly translates into reduced anodic overpotential for cells that ran for 1300 cycles in Al plating/stripping tests,the longest cycling life reported to date.This unique combination of salt and additive is non-corrosive,exhibits a high flash point and is cheaper than traditionally reported RAB electrolyte combinations,which makes it commercially promising.Through this report,we address a major roadblock in the commercialization of RAB and inspire equivalent electrolyte fabrication approaches for other metal anode batteries.展开更多
BTEX contaminants in groundwater seriously impact the ecological environment and human health that has become one of the urgent problems needed to be solved.Due to its low density,low solubility and strong volatility,...BTEX contaminants in groundwater seriously impact the ecological environment and human health that has become one of the urgent problems needed to be solved.Due to its low density,low solubility and strong volatility,BTEX in groundwater usually form non-aqueous phase liquid(NAPL) contaminants and exist in three phases:gas,aqueous and oil phase.Air sparging(AS) is an in situ treatment technology展开更多
Objective:The objective of the present study was to develop floating microspheres of Cefpodoxime Proxetil in order to achieve an extended retention in the upper GIT,which may result in enhanced absorption and there by...Objective:The objective of the present study was to develop floating microspheres of Cefpodoxime Proxetil in order to achieve an extended retention in the upper GIT,which may result in enhanced absorption and there by improved bioavailability.Methods:The microspheres were prepared by non - aqueous solvent evaporation method using polymers such as Hydroxyl Propyl Methyl Cellulose（HPMC K15M）,Ethyl Cellulose（EC） in different ratios,and Cefpodoxime Proxetil contain in each formulation.In vitro drug release were performed by USP apparatus type I andthe microspheres were characterized by calculating percentage yield,particle size analysis, buoyancy percentage,drug entrapment efficiencyand in vitro drug release studies.Results:The result showed microspheres yield were 50.50%-72.21%,particle size were distributed between75-600μm,drug entrapment efficiency were 14.1%-28.2%,buoyancy percentage were 70.10%-88.25%.Conclusion: Cefpodoxime Proxetil floating microspheres,at the lower polymer to drug ratio,there was a significant drug release. The better drug release profile was seen with FA<sub>2</sub> with ratio of drug polymer（1:2）.展开更多
The complete analytical procedure using coulometric titration to determine dissolved inorganic carbon (DIC) in seawater consists of studying the setup of the coulometric titration, the solution composition of the coul...The complete analytical procedure using coulometric titration to determine dissolved inorganic carbon (DIC) in seawater consists of studying the setup of the coulometric titration, the solution composition of the coulometer cell. conrrectly judging the titration end-point, and establishing(and evaluating the accuracy of) the DIC determination system.展开更多
Non-aqueous extraction(NAE)of bitumen from oil sands has been gaining great attention from both the industry and academia as an alternative to the water-based extraction.A fine solids removal step is important for a N...Non-aqueous extraction(NAE)of bitumen from oil sands has been gaining great attention from both the industry and academia as an alternative to the water-based extraction.A fine solids removal step is important for a NAE process in order to obtain high-quality bitumen product,which,however,remains a great challenge to reduce the fine solids content to the desired level.Here,we introduce a strategy of destabilizing the bitumen-coated silica particles in toluene with the addition of water and biomolecules extracted from Cyamopsiste tragonolobuosr L.Taup.,i.e.,high molecular weight guar gum(HGG)and low molecular weight guar gum(LGG),respectively.By virtue of sedimentation tests and focused beam reflectance measurement analysis,we demonstrate that the introduced water droplets modified with these biomolecules can facilitate the settling of the solid particles in toluene although the underlying mechanisms differ between these two biomolecule cases.Specifically,in the case of LGG,the added water droplets with the interfacial amphiphilic LGG can strengthen the attachment of solid particles from bulk toluene to the LGG surface.This research work provides useful insight into the development of effective approaches for destabilization and removal of bitumen-coated fine solids from NAE bitumen.展开更多
基金supported by Natural Science Foundation of Shanghai (20ZR1400300)Textile Vision Applied Basic Research Project (J202005)National Key Research & Development Program of China (2017YFB0309600)。
文摘The development of pollution-free dyeing technology, including anhydrous dyeing and non-aqueous dyeing technologies, has always been an important way and research hot in energy conservation and emission reduction. Designing new structural dye molecules is the key to water-saving dyeing processes.Herein, three reactive dyes were designed and synthesized, which contained large planar multiconjugated systems and multi-reactive groups. The designed reactive dyes are expected to have high affinity and high fixations in non-aqueous or small bath dyeing processes. The reactive dyes were applied in the decamethylcyclopentasiloxane(DMCS) reverse micelle dyeing for cotton fabric. High exhaustion rate of 99.35%, 98.10% and 98.80%, and fixation rate of 95.15%, 96.34% and 94.40% for three dyes, R1,R2 and R3, could be respectively obtained. The dyes can be fully utilized and had excellent dyeing performance, fastness and levelling properties under the revere micelle dyeing. The cotton fabric is like an oil-water separator in the dyeing process, where the dye micelles rapidly absorb and permeate into the cotton fibers. DMCS circulates around the fabric to transfer mass and energy. After dyeing, the solvent can be separated quickly and reused. The new reactive dyes containing large planar and multi-conjugated systems have potential application in green and sustainable dyeing technology with less wastewater and higher utilization.
文摘The scenario of geothermal tunnel is commonly observed around the world,and increases with the new constructions in the long and deep tunnels,for example in China.Tunnel insulation is generally divided into active and passive insulation.In passive insulation,it is an effective way to set low thermal con-ductivity materials as the thermal insulation layer as the choice of insulation material mainly depends on the thermal conductivity.Polymer is a kind of material with good geothermal performance,but there are relatively few studies.In this context,the transient plane source(TPS)method was used to measure the thermal conductivity of the developed polymer.Then,the temperature field of the high geothermal tunnel insulated by the non-aqueous reactive polymer layer was simulated.With the parametric analysis results,the suggestions for the tunnel layers were proposed accordingly.It revealed that the thermal conductivity of polymer first increases and then decreases with temperature.There are two rising sec-tions(?40e10?C and 20e90?C),one flat section(10e20?C)and one descending section(>90?C).It is observed the thermal conductivity of polymer increases with increase of the density of insulation layer and the density,and the thermal conductivity decreases when exposed to high temperatures.The temperature of the surrounding rocks increases with increase of the thermal conductivity and the thickness of polymer.Finally,a more economical thickness(5 cm)was proposed.Based on the parametric study,a thermal insulation layer with thermal conductivity less than 0.045 W/(m K),thickness of 5 cm and a density less than 0.12 g/cm 3 is suggested for practice.
基金financial supported by the Natural Science Foundation of China(Grant No.21476224,21406219 and 51361135701)
文摘Flow batteries with high energy density and long cycle life have been pursued to advance the progress of energy storage and grid application. Non-aqueous batteries with wide voltage windows represent a promising technology without the limitation of water electrolysis, but they suffer from low electrolyte concentration and unsatisfactory battery performance. Here, a non-aqueous lithium bromine rechargeable battery is proposed, which is based on Br_2/Br^-and Li^+/Li as active redox pairs, with fast redox kinetics and good stability. The Li/Br battery combines the advantages of high output voltage(~3.1 V),electrolyte concentration(3.0 mol/L), maximum power density(29.1 m W/cm^2) and practical energy density(232.6 Wh/kg). Additionally, the battery displays a columbic efficiency(CE) of 90.0%, a voltage efficiency(VE) of 88.0% and an energy efficiency(EE) of 80.0% at 1.0 m A/cm^2 after continuously running for more than 1000 cycles, which is by far the longest cycle life reported for non-aqueous flow batteries.
基金CAS-DOE Collaborative Project(121421KYSB20170032)DICP funding(ZZBS201707)National Natural Science Foundation of China(21706253)。
文摘The demands for high-performance and low-cost batteries make K-ion batteries(KIBs) considered as promising supplements or alternatives for Li-ion batteries(LIBs). Nevertheless, there are only a small amount of conventional inorganic electrode materials that can be used in KIBs, due to the large radius of K^+ ions. Diff erently, organic electrode materials(OEMs) generally own sufficiently interstitial space and good structure flexibility, which can maintain superior performance in K-ion systems. Therefore, in recent years, more and more investigations have been focused on OEMs for KIBs. This review will comprehensively cover the researches on OEMs in KIBs in order to accelerate the research and development of KIBs. The reaction mechanism, electrochemical behavior, etc., of OEMs will all be summarized in detail and deeply. Emphasis is placed to overview the performance improvement strategies of OEMs and the characteristic superiority of OEMs in KIBs compared with LIBs and Na-ion batteries.
文摘Unilamellar vesicles from the mixtures of 1:1 sodium 10-undecenoate and trimethyl[2-(10-undecenoyloxy) ethyl]ammonium iodide in the mixed solvents of ethanol and heptane can be formed spontaneously or by sonication. They can ekist in the variation of concentrations and volume ratios of ethanol to heptane. Which indicates to some extent the high capability of vesicle formation in such mixed
文摘Polyoxometalates have been explored as multi-electron active species in both aqueous and non-aqueous redox flow batteries. Although non-aqueous systems in principle offer a wider voltage window for redox flow battery operation, realization of this potential requires a judicious choice of solvent as well as polyoxometalate properties. We demonstrate here the superior performance of N,N-dimethylformamide(DMF)compared to acetonitrile as a solvent for redox flow batteries based on Li3PMo12O40. This compound displays two 1-electron transfers in acetonitrile but can access an extra quasi-reversible 2-electron redox process in DMF. A cell containing 10 mM solution of Li3PMo12O40 in DMF produced a cell voltage of 0.7 V with 2-electron transfers(State of Charge = 60%) and showed a good cyclability. As a means to boost energy density, operation of the redox flow battery at a higher concentration of 0.1 M Li3PMo12O40 produced cells with cell voltage of 0.6 V in acetonitrile and a cell voltage of 1.0 V in DMF;both showed excellent coulombic efficiencies of more than 90% over the course of 30 cycles. Energy density was also increased by employing an asymmetric cell with different polyoxometalates on each side to extend cell voltage.Li6P2W18O62 exhibited 3 quasi-reversible 2-electron transfers in the potential range between-2.05 V and-0.5 V vs. Ag/Ag+. 10 mM Li6P2W18O62/Li3PMo12O40 in DMF produced a cell with cell voltage of 1.3 V involving 4-electron transfers(State of Charge = 50%) with coulombic efficiency of nearly 100% and energy efficiency of nearly 70% throughout the test with more than 20 cycles. These promising results demonstrate proof-of-concept approaches to improving the performance of polyoxometalates in non-aqueous redox flow batteries.
文摘Standard free energies (ΔG0t(i) ) and entropies (ΔS0t(i)) of transfer of some homologous α-amino acids viz. glycine (gly), dl-alanine (ala), dl-α-amino butyric acid (aba) and dl-nor-valine (nor-val) from protic ethylene glycol (EG) to dipolar aprotic N,N-dimethyl formamide (DMF) have been evaluated from solubility measure-ments at five equidistant temperatures i.e from 15 to 350C. The observed ΔG0t(i) and TΔS0t(i) Vs composition profiles are complicated because of the various interaction effects. The chemical effects of the transfer Gibbs energies (ΔG0t.ch(i)) and entropies of transfer (ΔS0t.ch(i)) have been obtained after elimination of cavity effect, estimated by the scaled particle theory and dipole-dipole interaction effects, estimated by the use of Keesom-orientation expression. The chemical contributions of transfer energetics of homologous α-amino acids are guided by the composite effects of increased dispersion interaction, basicity and decreased acidity, hydrogen bonding effects and solvophobic solvation of ethylene glycol and N, N-dimethyl formamide mixed solvent as compared to that of reference solvent (ethylene glycol).
基金supported by the National Natural Science Foundation of China(Nos:51503038 and 51873037).
文摘The exploitation of high performance redox-active substances is critically important for the development of non-aqueous redoxflow batteries.Herein,three tetrathiofulvalene(TTF)derivatives with different substitution groups,namely TTF diethyl ester(TTFDE),TTF tetramethyl ester(TTFTM),and TTF tetraethyl ester(TTFTE),are prepared and their energy storage properties are evaluated.It has been found that the redox potential and solubility of these TTF derivatives in conventional carbonate electrolytes increases with the number of ester groups.The battery with a catholyte of 0.2 mol L^(-1) of TTFTE delivers a specific capacity of more than 10 Ah L^(-1) at the current density of 0.5 C with two discharge voltage platforms locating at as high as 3.85 and 3.60 V vs.Li/Liþ.Its capacity retention can be improved from 2.34 Ah L^(-1) to 3.60 Ah L^(-1) after 100 cycles by the use of an anion exchange membrane to block the crossover of TTF species.The excellent cycling stability of the TIF esters is supported by their well-delocalized electrons,as revealed by the density function theory calculations.Therefore,the introduction of more and larger electron-withdrawing groups is a promising strategy to simultaneously increase the redox-potential and solubility of redox-active ma-terials for non-aqueous redoxflow batteries.
基金National Natural Science Foundation of China(Nos.51671124 and 51474142)State Key Laboratory of Development and Application Technology of Automotive Steel(Baosteel Group).
文摘Three-dimensional investigation of sulfides is required in order to improve the mechanical properties of steel by controlling the sulfides in the steel.A method including its principles and device is introduced for the investigation of threedimensional morphology of sulfides.The method is suitable for gear steel,free cutting steel,non-quenched steel,tempered steel(ws≥0.02 wt.%),etc.The influences of current density,time,and temperature on the exposure degree of sulfide inclusions were investigated by using 16MnCrS5 steel.The best parameters of electrolytic etching of sulfur steel,as found by experimentation,are as follows:current density,37.5-52.5 mA/cm2;time,30-35 min;and temperature,—10 to 0℃.Under these conditions,the three-dimensional morphology of sulfide inclusions in sulfur-bearing steel can be exposed effectively.
基金supported by the National Natural Science Foundation of Chinathe Chimbing Project of the National Committee of ScienceTechnology of China.
文摘Nanocrystalline semiconductors are potentially useful materials due to their novel prop-erties which are markedly different from those of the bulk solids,the most notable one beingquantum confinement.Preparation and application of nanocrystalline Ⅲ-V class of materialssuch as InP have recently attracted much attention.It is difficult to synthesize Ⅲ-V mat-erials by use of the traditional solid-state methods,due to their high synthesis temper-
基金financial support from the National Natural Science Foundation of China(No.51777140)the Fundamental Research Funds for the Central Universities at Tongji University(No.22120180519/22120180308)partly supported by US Army Research Laboratory(No.W911NF-12-R-0011-03)。
文摘The energy density of non-aqueous carbon-based electrochemical capacitors(cEC)is mainly determined by the specific capacitance and operational voltage range.In this study,we propose to construct an unbalanced structure to make full use of stable voltage range for improving energy density.The stable voltage range is firstly carefully explored using cyclic voltammetry.Then an unbalanced carbon-based electrochemical capacitor(ucEC)is constructed with an optimized positive electrode to negative electrode weight ratio and voltage range.Its electrochemical performance is comprehensively investigated,including energy density,power density as well as cycle life.The ucEC is capable to deliver an improved energy density up to 64.9 Wh/kg(1.4 times as high as a general cEC)without sacrificing the power density and cycle life.The electrode properties after cycling are also analyzed,illustrating the change of electrode potential caused by unbalanced structure.The proposed structure demonstrates a great potential for improving the energy density at little cost of electrode design and cell configuration.
基金the National Natural Science Foundation of China(Grant No.20375051)the Excellent Young Teachers Program of Ministry of Education(Grant No.[2002]123)
文摘The electrostatic interaction between additive and analyte is of great importance to non-aqueous cap- illary electrophoresis(NACE)separation.Three tetraalkylammonium bromides and acetonitrile were applied as additives and running solvent respectively.The effect of alkyl chain length and concentra- tion of additive on electrostatic interactions was investigated by the separation of phenols.The sepa- ration ability was found to increase with decreasing alkyl chain length of the additive,and the resolu- tion values were increased with increasing additive concentration.The separation was seriously dete- riorated after a little amount of water was added in the running solution.Furthermore,the electrostatic interaction is strong under the conditions of low electron cloud density,weak steric hindrance and multi-interaction sites.Thus,the separation result can be predicted by theoretical analysis,which is helpful for the separation of other substances in NACE based on electrostatic interaction.
基金support by the National Natural Science Foundation of China(Nos.21202037,21401044)Doctor Fund of Henan University of Technology(No.2013BS066).
文摘A novel[2]pseudorotaxane of cucurbit[6]uril(CB[6])and 1-butyl-3-methyl-imidazolium bromide([C4mim]Br)was synthesized by directly mixing the host and the guest molecules in non-aqueous system.Structural characteri-zations of the[2]pseudorotaxane were carried out by 1D,2D NMR and X-ray crystallography techniques both in solution and in crystal structure.The crystal structure demonstrated that CB[6]and[C4mim]Br formed a complex with the ratio 1∶1,in which one guest[C4mim]Br was included inside the CB[6],while two other[C4mim]Br molecules were free and surrounded the[2]pseudorotaxane as solvent molecules,which could stabilize the crystal structure through hydrogen bonds.Moreover,parallel solvent channels consisting by free[C4mim]Br molecules occupied the pores among the frame of the pseudorotaxanes and formed zigzag lines in the crystal structure.[C4mim]Br can serve as not only the guest reactant but also the solvent in the formation of[2]pseudorotaxane for-mation.
基金This work was supported by the National Natural Science Foundation of China(Nos.51771177,51972141,21621001,21835002)the Jilin Province Science and Technology Development Program,China(No.20190303104SF)+3 种基金the Jilin Province/Jilin University Co-construction Project-Funds for New Materials,China(No.SXGJSF2017-3)the Science and Technology Breakthrough Plan of Henan Province,China(Nos.202102210242,212102210186)the Key Scientific Research Project of Higher Education of Henan Province,China(No.21A150055)the Undergraduate Innovation and Entrepreneurship Training Program of Zhengzhou University of Technology,China(No.201911068020).
文摘The instabilities of the battery including cathode corrosion/passivation,shuttling effect of the redox mediators,Li anode corrosion,and electrolyte decomposition are major barriers toward the practical implementation of lithium-oxygen(Li-O2)batteries.Functional materials offer great potential in high performance Li-O2 batteries owing to their functional tailorability of chemical modification for alleviating side reactions and improving catalysis activity,well-defined properties for discharge products storage,and fast mass and electron transfer paths.In this review,instability problems of non-aqueous Li-O2 batteries and recent studies related to the functional materials in tackling the instability issues from rational cathode construction,inhibition of redox mediators(RMs)shuttling,anode protection and novel electrolyte design are illustrated.Future research directions to overcome the critical issues are also proposed for this promising battery technology.The instability issues and the related strategies with functional materials based on the comprehensive consideration of all battery components proposed in this review provide the systematic,deep understanding and rational design of functional materials for Li-O2 batteries,which is beneficial to achieving the practical Li-O2 batteries.
文摘Manganese(Mn)doped cadmium sulphide(Cd S)nanoparticles were synthesized using a chemical method.It was possible to decrease Cd S:Mn particle size by increasing Mn concentration.Investigation techniques such as ultraviolet-visible(UV-Vis)absorption spectroscopy and photoluminescence(PL)spectroscopy were used to determine optical properties of Cd S:Mn nanoparticles.Size quantization effect was observed in UV-Vis absorption spectra.Quantum efficiency for luminescence or the internal magnetic field strength was increased by doping Cd S nanoparticles with Mn element.Orange emission was observed at wavelength~630 nm due to ^(4)T_1→^(6)A_1 transition.Isolated Mn~(2+)ions arranged in tetrahedral coordination are mainly responsible for luminescence.Luminescence quenching and the effect of Mn doping on hyperfine interactions in the case of Cd S nanoparticles were also discussed.The corresponding weight percentage of Mn element actually incorporated in doping process was determined by atomic absorption spectroscopy(AAS).Crystallinity was checked and the average size of nanoparticles was estimated using the X-ray diffraction(XRD)technique.Cd S:Mn nanoparticles show ferromagnetism at room temperature.Transmission electron microscopy(TEM)images show spherical clusters of various sizes and selected area electron diffraction(SAED)patterns show the polycrystalline nature of the clusters.The electronic states of diluted magnetic semiconductors(DMS)ofⅡ-Ⅵgroup Cd S nanoparticles give them great potential for applications due to quantum confinement.In this study,experimental results and discussions on these aspects have been given.
基金the financial support from Agency for Science, Technology and Research (Central Research Fund Award)
文摘Rechargeable Al batteries(RAB)are promising candidates for safe and environmentally sustainable battery systems with low-cost investments.However,the currently used aluminum chloridebased electrolytes present a significant challenge to commercialization due to their corrosive nature.Here,we report for the first time,a novel electrolyte combination for RAB based on aluminum trifluoromethanesulfonate(Al(OTf)_(3))with tetrabutylammonium chloride(TBAC)additive in diglyme.The presence of a mere 0.1 M of TBAC in the Al(OTf)_(3) electrolyte generates the charge carrying electrochemical species,which forms the basis of reaction at the electrodes.TBAC reduces the charge transfer resistance and the surface activation energy at the anode surface and also augments the dissociation of Al(OTf)_(3) to generate the solid electrolyte interphase components.Our electrolyte’s superiority directly translates into reduced anodic overpotential for cells that ran for 1300 cycles in Al plating/stripping tests,the longest cycling life reported to date.This unique combination of salt and additive is non-corrosive,exhibits a high flash point and is cheaper than traditionally reported RAB electrolyte combinations,which makes it commercially promising.Through this report,we address a major roadblock in the commercialization of RAB and inspire equivalent electrolyte fabrication approaches for other metal anode batteries.
文摘BTEX contaminants in groundwater seriously impact the ecological environment and human health that has become one of the urgent problems needed to be solved.Due to its low density,low solubility and strong volatility,BTEX in groundwater usually form non-aqueous phase liquid(NAPL) contaminants and exist in three phases:gas,aqueous and oil phase.Air sparging(AS) is an in situ treatment technology
文摘Objective:The objective of the present study was to develop floating microspheres of Cefpodoxime Proxetil in order to achieve an extended retention in the upper GIT,which may result in enhanced absorption and there by improved bioavailability.Methods:The microspheres were prepared by non - aqueous solvent evaporation method using polymers such as Hydroxyl Propyl Methyl Cellulose（HPMC K15M）,Ethyl Cellulose（EC） in different ratios,and Cefpodoxime Proxetil contain in each formulation.In vitro drug release were performed by USP apparatus type I andthe microspheres were characterized by calculating percentage yield,particle size analysis, buoyancy percentage,drug entrapment efficiencyand in vitro drug release studies.Results:The result showed microspheres yield were 50.50%-72.21%,particle size were distributed between75-600μm,drug entrapment efficiency were 14.1%-28.2%,buoyancy percentage were 70.10%-88.25%.Conclusion: Cefpodoxime Proxetil floating microspheres,at the lower polymer to drug ratio,there was a significant drug release. The better drug release profile was seen with FA<sub>2</sub> with ratio of drug polymer（1:2）.
文摘The complete analytical procedure using coulometric titration to determine dissolved inorganic carbon (DIC) in seawater consists of studying the setup of the coulometric titration, the solution composition of the coulometer cell. conrrectly judging the titration end-point, and establishing(and evaluating the accuracy of) the DIC determination system.
基金the financial support from Institute for Oil Sands Innovation(IOSI),Imperial Oil,the Natural Sciences and Engineering Research Council of Canada(NSERC)and Alberta Innovates to the research workthe financial support from the Canada Foundation for Innovation(CFI),the Future Energy Systems underthe Canada First Research Excellence Fund and the Canada Research Chairs Program。
文摘Non-aqueous extraction(NAE)of bitumen from oil sands has been gaining great attention from both the industry and academia as an alternative to the water-based extraction.A fine solids removal step is important for a NAE process in order to obtain high-quality bitumen product,which,however,remains a great challenge to reduce the fine solids content to the desired level.Here,we introduce a strategy of destabilizing the bitumen-coated silica particles in toluene with the addition of water and biomolecules extracted from Cyamopsiste tragonolobuosr L.Taup.,i.e.,high molecular weight guar gum(HGG)and low molecular weight guar gum(LGG),respectively.By virtue of sedimentation tests and focused beam reflectance measurement analysis,we demonstrate that the introduced water droplets modified with these biomolecules can facilitate the settling of the solid particles in toluene although the underlying mechanisms differ between these two biomolecule cases.Specifically,in the case of LGG,the added water droplets with the interfacial amphiphilic LGG can strengthen the attachment of solid particles from bulk toluene to the LGG surface.This research work provides useful insight into the development of effective approaches for destabilization and removal of bitumen-coated fine solids from NAE bitumen.
