Adsorptive separation holds important prospect for the challenging recovery of C_(2)H_(6) and C_(3)H_(8) from natural gas and the separation efficiency is primarily determined by a high-performance adsorbent.In this w...Adsorptive separation holds important prospect for the challenging recovery of C_(2)H_(6) and C_(3)H_(8) from natural gas and the separation efficiency is primarily determined by a high-performance adsorbent.In this work,we reported the synthesis of a novel porous organic polymer,FOSU-POP-1 for the separation of CH_(4)/C_(2)H_(6)/C_(3)H_(8).The FOSU-POP-1 was synthesized from tetrakis(4-azidophenyl)methane and 1,3,5-triethynylbenzene via click reaction with a Brunauer-Emmett-Teller(BET)surface area of 1038 m^(2)·g^(-1).Exhibiting stronger affinity towards C_(3)H_(8) and C_(2)H_(6) than CH_(4),2.85 mmol·g^(-1) for C_(3)H_(8) and 2.14 mmol·g^(-1) for C_(2)H_(6) were achieved on the FOSU-POP-1 at 0.1 MPa,298 K,with an ideal adsorbed solution theory selectivity of 227 for C_(3)H_(8)/CH_(4).The breakthrough experiment confirmed the good dynamic separation performance and recyclability of FOSU-POP-1 for CH_(4)/C_(2)H_(6)/C_(3)H_(8) ternary mixture.The density functional theory calculation further revealed that the N atom in triazole ring interacted strongly with the C_(3)H_(8) and C_(2)H_(6).This work highlighted the promising capability of FOSU-POP-1 for efficiently separating CH_(4)/C_(2)H_(6)/C_(3)H_(8) mixture.展开更多
Heterostructured photocatalysts provide an effective way to achieve enhanced photocatalytic performances through efficient charge separation.Although both wide-and narrow-band-gap photocatalysts have been widely inves...Heterostructured photocatalysts provide an effective way to achieve enhanced photocatalytic performances through efficient charge separation.Although both wide-and narrow-band-gap photocatalysts have been widely investigated,the charge separation and transfer mechanism at the contacting interface of the two has not been fully revealed.Here,a novel SrTiO3/BiOI(STB)heterostructured photocatalyst was successfully fabricated by using a facile method.The heterostructure in the photocatalyst extends the photoabsorption to the visible light range,and thus,high photocatalytic NO removal performance can be achieved under visible light irradiation.A combination of experimental and theoretical evidences indicated that the photogenerated electrons from the BiOI semiconductor can directly transfer to the SrTiO3 surface through a preformed electron delivery channel.Enhanced electron transfer was expected between the SrTiO3 and BiOI surfaces under light irradiation,and leads to efficient ROS generation and thus a high NO conversion rate.Moreover,in situ diffused reflectance infrared Fourier transform spectroscopy revealed that STB can better inhibit the accumulation of the toxic intermediate NO2 and catalyze the NO oxidation more effectively.This work presents a new insight into the mechanism of the interfacial charge separation in heterostructures and provides a simple strategy to promote the photocatalytic technology for efficient and safe air purification.展开更多
In this work,a simple method was carried out to successfully fabricate superoleophilic and superhydrophobic N-dodecyltrimethoxysilane@tungsten trioxide coated copper mesh.The as-fabricated copper mesh displayed promin...In this work,a simple method was carried out to successfully fabricate superoleophilic and superhydrophobic N-dodecyltrimethoxysilane@tungsten trioxide coated copper mesh.The as-fabricated copper mesh displayed prominent superoleophilicity and superhydrophobicity with a huge water contact angle about 154.39°and oil contact angle near 0°Moreover,the coated copper mesh showed high separation efficiency approximately 99.3%,and huge water flux about 9962.3 L·h^-1·m-2,which could be used to separate various organic solvents/water mixtures.Furthermore,the coated copper mesh showed favorable stability that the separation efficiency remained above 90%after 10 separation cycles.Benefiting from the excellent photocatalytic degradation ability of tungsten trioxide,the coated copper mesh possessed the self-cleaning capacity.Therefore,the mesh contaminated with lubricating oil could regain superhydrophobic property,and this property of self-cleaning permitted that the fabricated copper mesh could be repeatedly used for oil and water separation.展开更多
Measurements of zero-degree breakup fragment energy distribution fromthe Coulomb-Explosions of 1.50965 MeV HD+ ion inicro-cluster beam are reported.Mean value of the internuclear separation of HD+ is found to be 0.125...Measurements of zero-degree breakup fragment energy distribution fromthe Coulomb-Explosions of 1.50965 MeV HD+ ion inicro-cluster beam are reported.Mean value of the internuclear separation of HD+ is found to be 0.12510.003 urn. Aset of high-resolution experimental arrangement and improvement of the Van-de-Graaffaccelerator are described briefly.展开更多
Fluoride removal by traditional precipitation generates huge amounts of a water-rich sludge with low quality, which has no commercial or industrial value. The present study evaluated the feasibility of recovering fluo...Fluoride removal by traditional precipitation generates huge amounts of a water-rich sludge with low quality, which has no commercial or industrial value. The present study evaluated the feasibility of recovering fluoride as low water content cryolite from industrial fluoride-containing wastewater. A novel pilot-scale reaction-separation integrated reactor was designed. The results showed that the seed retention time in the reactor was prolonged to strengthen the induced crystallization process. The particle size of cryolite increased with increasing seed retention time, which decreased the water content. The recovery rate of cryolite was above 75% under an influent fluoride concentration of 3500 mg/L, a reaction temperature of 50°C, and an influent flow of 40 L/hr. The cryolite products that precipitated from the reactor were small in volume, large in particle size, low in water content, high in crystal purity, and recyclable.展开更多
A novel method of controlling the shape memory properties of shape memory polyurethane （SMPU） by addition of micro-phase separation promoters including 1-octadecanol （ODO） and liquid paraffin （LP） is reported. T...A novel method of controlling the shape memory properties of shape memory polyurethane （SMPU） by addition of micro-phase separation promoters including 1-octadecanol （ODO） and liquid paraffin （LP） is reported. The results indicate that the strain recovery temperature and the strain modulus rate （Eg/Er） were increased significantly with addition of small amount of micro-phase separation promoters. Thus it can increase the shape memory fixity rate and other shape memory behaviors of SMPU.展开更多
Uncontrolled dendrite growth,sluggish reaction kinetics,and drastic side reactions on the anodeelectrolyte interface are the main obstacles that restrict the application prospect of aqueous zinc-ion batteries.Traditio...Uncontrolled dendrite growth,sluggish reaction kinetics,and drastic side reactions on the anodeelectrolyte interface are the main obstacles that restrict the application prospect of aqueous zinc-ion batteries.Traditional glass fiber(GF)separator with chemical inertness is almost ineffective in restricting these challenges.Herein,inspired by the ionic enrichment behavior of seaweed plants,a facile biomass species,anionic sodium alginate(SA),is purposely decorated on the commercial GF separator to tackle these issues towards Zn anode.Benefiting from the abundant zincophilic functional groups and superior mechanical strength properties,the as-obtained SA@GF separator could act as ion pump to boost the Zn^(2+)transference number(0.68),reduce the de-solvation energy barrier of hydrated Zn^(2+),and eliminate the undesired concentration polarization effect,which are verified by experimental tests,theoretical calculations,and finite element simulation,respectively.Based on these efficient modulation mechanisms,the SA@GF separator can synchronously achieve well-aligned Zn deposition and the suppression of parasitic side-reactions.Therefore,the Zn‖Zn coin cell integrated with SA@GF separator could yield a prolonged calendar lifespan over 1230 h(1 mA cm^(-2)and 1 mAh cm^(-2)),exhibiting favorable competitiveness with previously reported separator modification strategies.Impressively,the Zn-MnO_(2)full and pouch cell assembled with the SA@GF separator also delivered superior cycling stability and rate performance,further verifying its practical application effect.This work provides a new design philosophy to stabilize the Zn anode from the aspect of separator.展开更多
The roles of reaction inhomogeneity in phase separation of polymer mixtures were described and summarized via two examples:photocross-link of polymer mixtures in the bulk state and photopolymerization of monomer in th...The roles of reaction inhomogeneity in phase separation of polymer mixtures were described and summarized via two examples:photocross-link of polymer mixtures in the bulk state and photopolymerization of monomer in the liquid state. The reaction kinetics,the reaction-induced elastic strain and the phase separation kinetics were monitored respectively by UV-Vis spectroscopy,Mach-Zehnder interferometry and laser-scanning confocal microscopy.It was found that phase separation in the bulk state was strongly inf...展开更多
Simultaneously inducing dual built-in electric fields(EFs)both within a single component and at the heterojunction interface creates a dual-driving force that is crucial for promoting spatial charge separation.This is...Simultaneously inducing dual built-in electric fields(EFs)both within a single component and at the heterojunction interface creates a dual-driving force that is crucial for promoting spatial charge separation.This is particularly significant in challenging coupled systems,such as CO_(2)photoreduction integrated with selective oxidation of toluene to benzaldehyde.However,developing such a system is quite challenging and often requires a precise design and engineering.Herein,we demonstrate a unique Ni-CdS@Ni(OH)_(2)heterojunction synthesized via an in-situ self-assembly method.Comprehensive mechanistic and theoretical investigations reveal that the NiCdS@Ni(OH)_(2)heterojunction induces dual electric fields(EFs):an intrinsic polarized electric-field within the CdS lattice from Ni doping and an interfacial electric-field from the growth of ultrathin nanosheets of Ni(OH)_(2)on NiCdS nanorods,enabling efficient spatial charge separation and enhanced redox potential.As proof of concept,the Ni-CdS@Ni(OH)_(2)heterojunction simultaneously exhibits outstanding bifunctional photocatalytic performance,producing CO at a rate of 427μmol g^(-1)h^(-1)and selectively oxidizing toluene to benzaldehyde at a rate of 1476μmol g^(-1)h^(-1)with a selectivity exceeding 85%.This work offers a promising strategy to optimize the utilization of photogenerated carriers in heterojunction photocatalysts,advancing synergistic photocatalytic redox systems.展开更多
Although photocatalytic water splitting has excellent potential for converting solar energy into chemical energy,the challenging charge separation process and sluggish surface catalytic reactions significantly limit p...Although photocatalytic water splitting has excellent potential for converting solar energy into chemical energy,the challenging charge separation process and sluggish surface catalytic reactions significantly limit progress in solar energy conversion using semiconductor photocatalysts.Herein,we demonstrate a feasible strategy involving the surface assembly of cobalt oxide species(CoO_(x))on a visible-light-responsive Cd_(0.9)Zn_(0.1)S(CZS)photocatalyst to fabricate a hierarchical CZS@CoO_(x) heterostructure.The unique hierarchical structure effectively accelerates the directional transfer of photogenerated charges,reducing charge recombination through the smooth interfacial heterojunction between CZS and CoO_(x),as evidenced by photoluminescence(PL)spectroscopy and various electrochemical characterizations.The surface cobalt species on the CZS material also act as efficient cocatalysts for photocatalytic hydrogen production,with activity even higher than that of noble metals.The well-defined CZS@CoO_(x) heterostructure not only enhances the interfacial separation of photoinduced charges,but also improves surface catalytic reactions.This leads to superior photocatalytic performances,with an apparent quantum efficiency of 20%at 420 nm for visible-light-driven hydrogen generation,which is one of the highest quantum efficiencies measured among noble-metal-free photocatalysts.Our work presents a potential pathway for controlling complex charge separation and catalytic reaction processes in photocatalysis,guiding the practical development of artificial photocatalysts for successful transformation of solar to chemical energy.展开更多
Early events of charge separation in reaction centers (RCs) of bacterial photosynthesis are modeled by kinetic equations with time-dependent rate constants. An illustrative case of regular motion along a “slow” coor...Early events of charge separation in reaction centers (RCs) of bacterial photosynthesis are modeled by kinetic equations with time-dependent rate constants. An illustrative case of regular motion along a “slow” coordinates leading to oscillations in the kinetics is examined. Different schemes of charge separation are investigated. A good fitting of experimental kinetics of native Rba. sphaeroides RCs is achieved in the five states model P*1BAHA↔P*2BAHA↔I↔P+HA↔P+BA with two excited states BAHA and BAHA and three charge separated states I, P+HA and P+BA (P is a primary electron donor, bacteriochlorophyll dimer, BA and HA are an electron acceptor, monomeric bacteriochlorophyll and bacteriopheophytin in active A-branch, respectively). In the model only the first excited state is directly populated by optical excitation. The emission of the two excited states is assumed to be at 905 and 940 nm, respectively. The intermediate state I is assumed to absorb at 1020 nm as well as the P+HA state. The model explains the deep oscillations in the kinetics of the stimulated emission and of the absorption. In the simpler schemes without the I state or with only one excited state the accordance with the experiment is achieved at unreal parameter values. A possible nature of the I and BAHA states and a possible incoherent nature of the oscillations are discussed.展开更多
The activities of protactinium were produced by the multi-nucleontransfer reactions in bombardment of the natural uranium with 60 MeV/nucleon 1sOions. A simple, relatively fast radiochemical procedure was used for ext...The activities of protactinium were produced by the multi-nucleontransfer reactions in bombardment of the natural uranium with 60 MeV/nucleon 1sOions. A simple, relatively fast radiochemical procedure was used for extraction sep-aration of protactinium from the uranium and a variety of reaction products using1-phenyl-3-methyl-4-benzoyl-5-pyrazolone and tri-iso-octylamine as extractants. Theγ ray spectrum of the separated protactinium fractions showed that the protactiniumcould be separated from all of the main impurity elements. The decontaminationfactors of the uranium and the main reaction products produced in the reaction aregiven.展开更多
Mutual separation characteristics for binary oxide mixtures Y2O3-Sc2O3, Y2O3-La2O3, Y2O3-Nd2O3 and Y2O3-Sm2O3 using a stepwise selective chlorination-chemical vapor transport（SC-CVT） reaction mediated by vapor compl...Mutual separation characteristics for binary oxide mixtures Y2O3-Sc2O3, Y2O3-La2O3, Y2O3-Nd2O3 and Y2O3-Sm2O3 using a stepwise selective chlorination-chemical vapor transport（SC-CVT） reaction mediated by vapor complexes KLnCl4 were investigated. The total transported yields of the chlorides produced from the oxide mixtures are in the order of NdCl3>SmCl3>LaCl3>YCl3>ScCl3, the main deposition temperature of the chlorides is in the order of ScCl3<YCl3<SmCl3<NdCl3<LaCl3, and the largest separation factor values are 1 100 for Y∶Sc, 14.88 for Y∶La, 9.86 for Y∶Nd and 16.45 for Y∶Sm in the temperature range from 1 000 K to )1 120 K,) while 157.7 for La∶Y, 51.6 for Nd∶Y and 12.4 for Sm∶Y in the temperature range from 1 200 K to 1 300 K, respectively. The results were discussed on the difference of KScCl4, KYCl4 and KLnCl4 and the selective chlorination of binary oxides at 800 K. Furthermore, the separation characteristics of vapor rare earth complex KLnCl4 were studied compared with those of LnAlnCl3n+3.展开更多
A series of mixed, random cylindrical brush copolymers bearing polystyrene（PS） and poly（ε-caprolactone）（PCL） side chains were synthesized via the combination of ring-opening polymerization（ROP） and atom trans...A series of mixed, random cylindrical brush copolymers bearing polystyrene（PS） and poly（ε-caprolactone）（PCL） side chains were synthesized via the combination of ring-opening polymerization（ROP） and atom transfer radical polymerization（ATRP）. These novel cylindrical brush copolymers have been characterized by means of nuclear magnetic resonance（NMR） spectroscopy, gel permeation chromatography（GPC） and differential scanning calorimetry（DSC）. It was found that the mikto-armed cylindrical brush copolymers were microphase-separated in bulks and that the morphologies were dependent on the mass ratios of PS to PCL side chains. One of the cylindrical brush copolymers was employed to incorporate into epoxy thermoset to investigate effect of the mikto-armed cylindrical brush architecture on the reaction-induced microphase separation behavior. Depending on the concentration of the cylindrical brush in epoxy, the thermosets can display the morphologies with the spherical, worm-like and lamellar PS microdomains dispersing in continuous thermosetting matrices.展开更多
The recovery of heterogeneous catalysts can save costs and avoid secondary pollution,but its separation efficiency and recovery cost are limited by conventional separation methods such as precipitation–flocculation,c...The recovery of heterogeneous catalysts can save costs and avoid secondary pollution,but its separation efficiency and recovery cost are limited by conventional separation methods such as precipitation–flocculation,centrifugation and filtration.In this paper,we found that surface-defective metal sulfides/oxides(WS2,CuS,ZnS,MoS2,CdS,TiO2,MoO2 and ZnO)commonly used in advanced oxidation processes(AOPs)could be magnetically recovered at room temperature and atmospheric pressure by mechanically mixing with Fe3O4.Zeta potential,Raman,X-ray photoelectron spectroscopy(XPS)and electro-spin resonance(ESR)spectra were measured to explore the mechanism of the magnetic separation phenomenon.The exposed active metal sites on the surface of defective metal sulfides/oxides are beneficial for the formation of chemical bonds,which are combined with electrostatic force to be responsible for the magnetic separation.Moreover,other factors affecting the magnetic separation were also investigated,such as the addition of amount of Fe3O4,different solvents and particle sizes.Finally,WS2 was chosen to be applied as a co-catalyst in Fenton reaction,which could be well separated by the magnetic Fe3O4 to achieve the recycle of catalyst in Fenton reaction.Our research provides a general strategy for the recycle of metal sulfides/oxides in the catalytic applications.展开更多
Heterogeneous reactions on the aerosol particle surface in the atmosphere play important roles in air pollution, climate change, and global biogeochemical cycles. However, the reported uptake coefficients of heterogen...Heterogeneous reactions on the aerosol particle surface in the atmosphere play important roles in air pollution, climate change, and global biogeochemical cycles. However, the reported uptake coefficients of heterogeneous reactions usually have large variations and may not be relevant to real atmospheric conditions. One of the major reasons for this is the use of bulk samples in laboratory experiments, while particles in the atmosphere are suspended individually. A number of technologies have been developed recently to study heterogeneous reactions on the surfaces of individual particles. Precise measurements on the reactive surface area, volume, and morphology of individual particles are necessary for calculating the uptake coefficient, quantifying reactants and products, and understanding the reaction mechanism better. In this study, for the first time we used synchrotron radiation X-ray computed tomography（XCT） and micro-Raman spectrometry to measure individual CaCO_3 particle morphology, with sizes ranging from 3.5–6.5 μm. Particle surface area and volume were calculated using a reconstruction method based on software threedimensional（3-D） rendering. The XCT was first validated with high-resolution fieldemission scanning electron microscopy（FE-SEM） to acquire accurate CaCO_3 particle surface area and volume estimates. Our results showed an average difference of only 6.1% in surface area and 3.2% in volume measured either by micro-Raman spectrometry or X-ray tomography. X-ray tomography and FE-SEM can provide more morphological details of individual Ca CO3 particles than micro-Raman spectrometry. This study demonstrated that X-ray computed tomography and micro-Raman spectrometry can precisely measure the surface area, volume, and morphology of an individual particle.展开更多
Herein,a new type of two-dimensional(2D)/2D Ti_(3)C_(2)/TiO_(2) heterojunction was developed for efficient photocatalytic nitrogen reduction reaction(NRR),in which TiO_(2) nanosheets(TiO_(2) Ns)were designed as the ma...Herein,a new type of two-dimensional(2D)/2D Ti_(3)C_(2)/TiO_(2) heterojunction was developed for efficient photocatalytic nitrogen reduction reaction(NRR),in which TiO_(2) nanosheets(TiO_(2) Ns)were designed as the main catalyst,while Ti_(3)C_(2) MXene served as the co-catalyst.Experimental and theoretical results revealed that Ti_(3)C_(2) MXene introduced electron-rich unsaturated Ti sites,serving as highly active sites for both the adsorption and activation of N_(2) on the Ti_(3)C_(2)/TiO_(2) heterojunction.Furthermore,the 2D/2D Ti_(3)C_(2)/TiO_(2) heterostructure greatly promoted the directional separation and transfer of charge carriers,facilitated by the internal electric field.This structural feature enabled the spatial separation of the N_(2) reduction and H2 O oxidation half-reactions on the distinct surfaces of Ti_(3)C_(2)(001)and TiO_(2)(001),con-sequently reducing the reaction energy barrier for each respective process.The synergistic effects arising from the interface and surface interactions within the heterojunction conspicuously improved the photo-catalytic NRR activity.As a result,the optimized Ti_(3)C_(2)/TiO_(2) heterojunction exhibited a high NH_(3) produc-tion rate of 24.4μmol g−1 h−1 in the absence of sacrificial agents,representing a remarkable 12.8-fold increase compared to individual TiO_(2) Ns.This work provides new insights into rational design of high-performance heterogeneous photocatalysts and offers a deeper understanding of the mechanism under-lying surface active sites in the photocatalytic NRR process.展开更多
Microbubbles have been widely used in the chemical industry in recent years due to their unique physical and chemical properties.This article provides an overview of the characteristics and main generation methods of ...Microbubbles have been widely used in the chemical industry in recent years due to their unique physical and chemical properties.This article provides an overview of the characteristics and main generation methods of microbubbles,including physical,chemical,mechanical,and microfluidic tech-niques.It also explores the applications of microbubbles in the chemical industry,such as gas-liquid reaction intensification, gas separation,mineral flotation, and preparation of high-performance poly olefin materials.By analyzing the current research status of microbubble technology,the future development direction of its application in the chemical industry is discussed.展开更多
基金financially supported by the National Natural Science Foundation of China(22208050,22108034)Guangdong Provincial Natural Science Foundation Project(2023A1515012151)Scientific Research Project of Guangdong Provincial Department of Education(2023KTSCX132).
文摘Adsorptive separation holds important prospect for the challenging recovery of C_(2)H_(6) and C_(3)H_(8) from natural gas and the separation efficiency is primarily determined by a high-performance adsorbent.In this work,we reported the synthesis of a novel porous organic polymer,FOSU-POP-1 for the separation of CH_(4)/C_(2)H_(6)/C_(3)H_(8).The FOSU-POP-1 was synthesized from tetrakis(4-azidophenyl)methane and 1,3,5-triethynylbenzene via click reaction with a Brunauer-Emmett-Teller(BET)surface area of 1038 m^(2)·g^(-1).Exhibiting stronger affinity towards C_(3)H_(8) and C_(2)H_(6) than CH_(4),2.85 mmol·g^(-1) for C_(3)H_(8) and 2.14 mmol·g^(-1) for C_(2)H_(6) were achieved on the FOSU-POP-1 at 0.1 MPa,298 K,with an ideal adsorbed solution theory selectivity of 227 for C_(3)H_(8)/CH_(4).The breakthrough experiment confirmed the good dynamic separation performance and recyclability of FOSU-POP-1 for CH_(4)/C_(2)H_(6)/C_(3)H_(8) ternary mixture.The density functional theory calculation further revealed that the N atom in triazole ring interacted strongly with the C_(3)H_(8) and C_(2)H_(6).This work highlighted the promising capability of FOSU-POP-1 for efficiently separating CH_(4)/C_(2)H_(6)/C_(3)H_(8) mixture.
基金supported by the National Natural Science Foundation of China(21822601,21501016,21777011)the National R&D Program of China(2016YFC02047)+1 种基金the Innovative Research Team of Chongqing(CXTDG201602014)the Natural Science Foundation of Chongqing(cstc2017jcyj BX0052)~~
文摘Heterostructured photocatalysts provide an effective way to achieve enhanced photocatalytic performances through efficient charge separation.Although both wide-and narrow-band-gap photocatalysts have been widely investigated,the charge separation and transfer mechanism at the contacting interface of the two has not been fully revealed.Here,a novel SrTiO3/BiOI(STB)heterostructured photocatalyst was successfully fabricated by using a facile method.The heterostructure in the photocatalyst extends the photoabsorption to the visible light range,and thus,high photocatalytic NO removal performance can be achieved under visible light irradiation.A combination of experimental and theoretical evidences indicated that the photogenerated electrons from the BiOI semiconductor can directly transfer to the SrTiO3 surface through a preformed electron delivery channel.Enhanced electron transfer was expected between the SrTiO3 and BiOI surfaces under light irradiation,and leads to efficient ROS generation and thus a high NO conversion rate.Moreover,in situ diffused reflectance infrared Fourier transform spectroscopy revealed that STB can better inhibit the accumulation of the toxic intermediate NO2 and catalyze the NO oxidation more effectively.This work presents a new insight into the mechanism of the interfacial charge separation in heterostructures and provides a simple strategy to promote the photocatalytic technology for efficient and safe air purification.
基金the National Natural Science Foundation of China(No.21776319 and No.21476269).
文摘In this work,a simple method was carried out to successfully fabricate superoleophilic and superhydrophobic N-dodecyltrimethoxysilane@tungsten trioxide coated copper mesh.The as-fabricated copper mesh displayed prominent superoleophilicity and superhydrophobicity with a huge water contact angle about 154.39°and oil contact angle near 0°Moreover,the coated copper mesh showed high separation efficiency approximately 99.3%,and huge water flux about 9962.3 L·h^-1·m-2,which could be used to separate various organic solvents/water mixtures.Furthermore,the coated copper mesh showed favorable stability that the separation efficiency remained above 90%after 10 separation cycles.Benefiting from the excellent photocatalytic degradation ability of tungsten trioxide,the coated copper mesh possessed the self-cleaning capacity.Therefore,the mesh contaminated with lubricating oil could regain superhydrophobic property,and this property of self-cleaning permitted that the fabricated copper mesh could be repeatedly used for oil and water separation.
文摘Measurements of zero-degree breakup fragment energy distribution fromthe Coulomb-Explosions of 1.50965 MeV HD+ ion inicro-cluster beam are reported.Mean value of the internuclear separation of HD+ is found to be 0.12510.003 urn. Aset of high-resolution experimental arrangement and improvement of the Van-de-Graaffaccelerator are described briefly.
基金supported by the Major Science and Technology Program of Hunan(China)(No.2009FJ-1009)
文摘Fluoride removal by traditional precipitation generates huge amounts of a water-rich sludge with low quality, which has no commercial or industrial value. The present study evaluated the feasibility of recovering fluoride as low water content cryolite from industrial fluoride-containing wastewater. A novel pilot-scale reaction-separation integrated reactor was designed. The results showed that the seed retention time in the reactor was prolonged to strengthen the induced crystallization process. The particle size of cryolite increased with increasing seed retention time, which decreased the water content. The recovery rate of cryolite was above 75% under an influent fluoride concentration of 3500 mg/L, a reaction temperature of 50°C, and an influent flow of 40 L/hr. The cryolite products that precipitated from the reactor were small in volume, large in particle size, low in water content, high in crystal purity, and recyclable.
基金We are grateful to the Natural Science Foundation of Hunan Province(Project no.01JJY33011)for financial support for this work.We also thank Dr.Yuan Li Cai for his assistance.
文摘A novel method of controlling the shape memory properties of shape memory polyurethane （SMPU） by addition of micro-phase separation promoters including 1-octadecanol （ODO） and liquid paraffin （LP） is reported. The results indicate that the strain recovery temperature and the strain modulus rate （Eg/Er） were increased significantly with addition of small amount of micro-phase separation promoters. Thus it can increase the shape memory fixity rate and other shape memory behaviors of SMPU.
基金supported by research grants from the National Natural Science Foundation of China(52173235,22008193,52106110)the Key Research and Development Project of Hainan Province(ZDYF2024SHFZ038)+2 种基金Venture&Innovation Support Program for Chongqing Overseas Returnees(CX2021018)Research Foundation of Chongqing University of Science and Technology(ckrc2021071)Numerical computations were performed on Hefei Advanced Computing Center.
文摘Uncontrolled dendrite growth,sluggish reaction kinetics,and drastic side reactions on the anodeelectrolyte interface are the main obstacles that restrict the application prospect of aqueous zinc-ion batteries.Traditional glass fiber(GF)separator with chemical inertness is almost ineffective in restricting these challenges.Herein,inspired by the ionic enrichment behavior of seaweed plants,a facile biomass species,anionic sodium alginate(SA),is purposely decorated on the commercial GF separator to tackle these issues towards Zn anode.Benefiting from the abundant zincophilic functional groups and superior mechanical strength properties,the as-obtained SA@GF separator could act as ion pump to boost the Zn^(2+)transference number(0.68),reduce the de-solvation energy barrier of hydrated Zn^(2+),and eliminate the undesired concentration polarization effect,which are verified by experimental tests,theoretical calculations,and finite element simulation,respectively.Based on these efficient modulation mechanisms,the SA@GF separator can synchronously achieve well-aligned Zn deposition and the suppression of parasitic side-reactions.Therefore,the Zn‖Zn coin cell integrated with SA@GF separator could yield a prolonged calendar lifespan over 1230 h(1 mA cm^(-2)and 1 mAh cm^(-2)),exhibiting favorable competitiveness with previously reported separator modification strategies.Impressively,the Zn-MnO_(2)full and pouch cell assembled with the SA@GF separator also delivered superior cycling stability and rate performance,further verifying its practical application effect.This work provides a new design philosophy to stabilize the Zn anode from the aspect of separator.
基金supported by the Ministry of Education (MONKASHO),Japan through the Grant-in-Aid on the Priority-Research-Area"Molecular Nanodynamics"and"Soft Matter Physics".The Grant-in-Aid for Scientific Research (No.20350107) is also gratefully acknowledged.
文摘The roles of reaction inhomogeneity in phase separation of polymer mixtures were described and summarized via two examples:photocross-link of polymer mixtures in the bulk state and photopolymerization of monomer in the liquid state. The reaction kinetics,the reaction-induced elastic strain and the phase separation kinetics were monitored respectively by UV-Vis spectroscopy,Mach-Zehnder interferometry and laser-scanning confocal microscopy.It was found that phase separation in the bulk state was strongly inf...
基金The authors sincerely appreciate funding from“Producing Hydrogen in Trentino-H2@TN”(PAT-Trento)through the research grant(SAP 40104237)Researchers Supporting Project number(RSP2025R399)King Saud University,Riyadh,Saudi Arabia.
文摘Simultaneously inducing dual built-in electric fields(EFs)both within a single component and at the heterojunction interface creates a dual-driving force that is crucial for promoting spatial charge separation.This is particularly significant in challenging coupled systems,such as CO_(2)photoreduction integrated with selective oxidation of toluene to benzaldehyde.However,developing such a system is quite challenging and often requires a precise design and engineering.Herein,we demonstrate a unique Ni-CdS@Ni(OH)_(2)heterojunction synthesized via an in-situ self-assembly method.Comprehensive mechanistic and theoretical investigations reveal that the NiCdS@Ni(OH)_(2)heterojunction induces dual electric fields(EFs):an intrinsic polarized electric-field within the CdS lattice from Ni doping and an interfacial electric-field from the growth of ultrathin nanosheets of Ni(OH)_(2)on NiCdS nanorods,enabling efficient spatial charge separation and enhanced redox potential.As proof of concept,the Ni-CdS@Ni(OH)_(2)heterojunction simultaneously exhibits outstanding bifunctional photocatalytic performance,producing CO at a rate of 427μmol g^(-1)h^(-1)and selectively oxidizing toluene to benzaldehyde at a rate of 1476μmol g^(-1)h^(-1)with a selectivity exceeding 85%.This work offers a promising strategy to optimize the utilization of photogenerated carriers in heterojunction photocatalysts,advancing synergistic photocatalytic redox systems.
文摘Although photocatalytic water splitting has excellent potential for converting solar energy into chemical energy,the challenging charge separation process and sluggish surface catalytic reactions significantly limit progress in solar energy conversion using semiconductor photocatalysts.Herein,we demonstrate a feasible strategy involving the surface assembly of cobalt oxide species(CoO_(x))on a visible-light-responsive Cd_(0.9)Zn_(0.1)S(CZS)photocatalyst to fabricate a hierarchical CZS@CoO_(x) heterostructure.The unique hierarchical structure effectively accelerates the directional transfer of photogenerated charges,reducing charge recombination through the smooth interfacial heterojunction between CZS and CoO_(x),as evidenced by photoluminescence(PL)spectroscopy and various electrochemical characterizations.The surface cobalt species on the CZS material also act as efficient cocatalysts for photocatalytic hydrogen production,with activity even higher than that of noble metals.The well-defined CZS@CoO_(x) heterostructure not only enhances the interfacial separation of photoinduced charges,but also improves surface catalytic reactions.This leads to superior photocatalytic performances,with an apparent quantum efficiency of 20%at 420 nm for visible-light-driven hydrogen generation,which is one of the highest quantum efficiencies measured among noble-metal-free photocatalysts.Our work presents a potential pathway for controlling complex charge separation and catalytic reaction processes in photocatalysis,guiding the practical development of artificial photocatalysts for successful transformation of solar to chemical energy.
文摘Early events of charge separation in reaction centers (RCs) of bacterial photosynthesis are modeled by kinetic equations with time-dependent rate constants. An illustrative case of regular motion along a “slow” coordinates leading to oscillations in the kinetics is examined. Different schemes of charge separation are investigated. A good fitting of experimental kinetics of native Rba. sphaeroides RCs is achieved in the five states model P*1BAHA↔P*2BAHA↔I↔P+HA↔P+BA with two excited states BAHA and BAHA and three charge separated states I, P+HA and P+BA (P is a primary electron donor, bacteriochlorophyll dimer, BA and HA are an electron acceptor, monomeric bacteriochlorophyll and bacteriopheophytin in active A-branch, respectively). In the model only the first excited state is directly populated by optical excitation. The emission of the two excited states is assumed to be at 905 and 940 nm, respectively. The intermediate state I is assumed to absorb at 1020 nm as well as the P+HA state. The model explains the deep oscillations in the kinetics of the stimulated emission and of the absorption. In the simpler schemes without the I state or with only one excited state the accordance with the experiment is achieved at unreal parameter values. A possible nature of the I and BAHA states and a possible incoherent nature of the oscillations are discussed.
基金Supported by the National Natural Science Foundation of China(10075063),and by the Chinese Academy of Sciences(TK95T-03)
文摘The activities of protactinium were produced by the multi-nucleontransfer reactions in bombardment of the natural uranium with 60 MeV/nucleon 1sOions. A simple, relatively fast radiochemical procedure was used for extraction sep-aration of protactinium from the uranium and a variety of reaction products using1-phenyl-3-methyl-4-benzoyl-5-pyrazolone and tri-iso-octylamine as extractants. Theγ ray spectrum of the separated protactinium fractions showed that the protactiniumcould be separated from all of the main impurity elements. The decontaminationfactors of the uranium and the main reaction products produced in the reaction aregiven.
文摘Mutual separation characteristics for binary oxide mixtures Y2O3-Sc2O3, Y2O3-La2O3, Y2O3-Nd2O3 and Y2O3-Sm2O3 using a stepwise selective chlorination-chemical vapor transport（SC-CVT） reaction mediated by vapor complexes KLnCl4 were investigated. The total transported yields of the chlorides produced from the oxide mixtures are in the order of NdCl3>SmCl3>LaCl3>YCl3>ScCl3, the main deposition temperature of the chlorides is in the order of ScCl3<YCl3<SmCl3<NdCl3<LaCl3, and the largest separation factor values are 1 100 for Y∶Sc, 14.88 for Y∶La, 9.86 for Y∶Nd and 16.45 for Y∶Sm in the temperature range from 1 000 K to )1 120 K,) while 157.7 for La∶Y, 51.6 for Nd∶Y and 12.4 for Sm∶Y in the temperature range from 1 200 K to 1 300 K, respectively. The results were discussed on the difference of KScCl4, KYCl4 and KLnCl4 and the selective chlorination of binary oxides at 800 K. Furthermore, the separation characteristics of vapor rare earth complex KLnCl4 were studied compared with those of LnAlnCl3n+3.
基金financially supported by the National Natural Science Foundation of China(Nos.51133003,21274091 and 21774078)the Shanghai Synchrotron Radiation Facility under the projects(Nos.10sr0260 and 10sr0126)
文摘A series of mixed, random cylindrical brush copolymers bearing polystyrene（PS） and poly（ε-caprolactone）（PCL） side chains were synthesized via the combination of ring-opening polymerization（ROP） and atom transfer radical polymerization（ATRP）. These novel cylindrical brush copolymers have been characterized by means of nuclear magnetic resonance（NMR） spectroscopy, gel permeation chromatography（GPC） and differential scanning calorimetry（DSC）. It was found that the mikto-armed cylindrical brush copolymers were microphase-separated in bulks and that the morphologies were dependent on the mass ratios of PS to PCL side chains. One of the cylindrical brush copolymers was employed to incorporate into epoxy thermoset to investigate effect of the mikto-armed cylindrical brush architecture on the reaction-induced microphase separation behavior. Depending on the concentration of the cylindrical brush in epoxy, the thermosets can display the morphologies with the spherical, worm-like and lamellar PS microdomains dispersing in continuous thermosetting matrices.
基金financially supported by the State Key Research Development Program of China (No. 2016YFA0204200the National Natural Science Foundation of China (Nos. 21822603, 21773062, 21577036, 21377038 and 21237003)+1 种基金Shanghai Pujiang Program (No. 17PJD011)the Fundamental Research Funds for the Central Universities (No. 22A201514021)
文摘The recovery of heterogeneous catalysts can save costs and avoid secondary pollution,but its separation efficiency and recovery cost are limited by conventional separation methods such as precipitation–flocculation,centrifugation and filtration.In this paper,we found that surface-defective metal sulfides/oxides(WS2,CuS,ZnS,MoS2,CdS,TiO2,MoO2 and ZnO)commonly used in advanced oxidation processes(AOPs)could be magnetically recovered at room temperature and atmospheric pressure by mechanically mixing with Fe3O4.Zeta potential,Raman,X-ray photoelectron spectroscopy(XPS)and electro-spin resonance(ESR)spectra were measured to explore the mechanism of the magnetic separation phenomenon.The exposed active metal sites on the surface of defective metal sulfides/oxides are beneficial for the formation of chemical bonds,which are combined with electrostatic force to be responsible for the magnetic separation.Moreover,other factors affecting the magnetic separation were also investigated,such as the addition of amount of Fe3O4,different solvents and particle sizes.Finally,WS2 was chosen to be applied as a co-catalyst in Fenton reaction,which could be well separated by the magnetic Fe3O4 to achieve the recycle of catalyst in Fenton reaction.Our research provides a general strategy for the recycle of metal sulfides/oxides in the catalytic applications.
基金supported by the Chinese Ministry of Science and Technology(No.2008AA062503)the National Natural Science Foundation Committee of China(Nos.41421064,20637020)the China Postdoctoral Science Foundation(No.20100470166)
文摘Heterogeneous reactions on the aerosol particle surface in the atmosphere play important roles in air pollution, climate change, and global biogeochemical cycles. However, the reported uptake coefficients of heterogeneous reactions usually have large variations and may not be relevant to real atmospheric conditions. One of the major reasons for this is the use of bulk samples in laboratory experiments, while particles in the atmosphere are suspended individually. A number of technologies have been developed recently to study heterogeneous reactions on the surfaces of individual particles. Precise measurements on the reactive surface area, volume, and morphology of individual particles are necessary for calculating the uptake coefficient, quantifying reactants and products, and understanding the reaction mechanism better. In this study, for the first time we used synchrotron radiation X-ray computed tomography（XCT） and micro-Raman spectrometry to measure individual CaCO_3 particle morphology, with sizes ranging from 3.5–6.5 μm. Particle surface area and volume were calculated using a reconstruction method based on software threedimensional（3-D） rendering. The XCT was first validated with high-resolution fieldemission scanning electron microscopy（FE-SEM） to acquire accurate CaCO_3 particle surface area and volume estimates. Our results showed an average difference of only 6.1% in surface area and 3.2% in volume measured either by micro-Raman spectrometry or X-ray tomography. X-ray tomography and FE-SEM can provide more morphological details of individual Ca CO3 particles than micro-Raman spectrometry. This study demonstrated that X-ray computed tomography and micro-Raman spectrometry can precisely measure the surface area, volume, and morphology of an individual particle.
基金supported by the National Natural Science Foundation of China(No.21773089)the Henan Center for Outstanding Overseas Scientist(No.GZS2024004).
文摘Herein,a new type of two-dimensional(2D)/2D Ti_(3)C_(2)/TiO_(2) heterojunction was developed for efficient photocatalytic nitrogen reduction reaction(NRR),in which TiO_(2) nanosheets(TiO_(2) Ns)were designed as the main catalyst,while Ti_(3)C_(2) MXene served as the co-catalyst.Experimental and theoretical results revealed that Ti_(3)C_(2) MXene introduced electron-rich unsaturated Ti sites,serving as highly active sites for both the adsorption and activation of N_(2) on the Ti_(3)C_(2)/TiO_(2) heterojunction.Furthermore,the 2D/2D Ti_(3)C_(2)/TiO_(2) heterostructure greatly promoted the directional separation and transfer of charge carriers,facilitated by the internal electric field.This structural feature enabled the spatial separation of the N_(2) reduction and H2 O oxidation half-reactions on the distinct surfaces of Ti_(3)C_(2)(001)and TiO_(2)(001),con-sequently reducing the reaction energy barrier for each respective process.The synergistic effects arising from the interface and surface interactions within the heterojunction conspicuously improved the photo-catalytic NRR activity.As a result,the optimized Ti_(3)C_(2)/TiO_(2) heterojunction exhibited a high NH_(3) produc-tion rate of 24.4μmol g−1 h−1 in the absence of sacrificial agents,representing a remarkable 12.8-fold increase compared to individual TiO_(2) Ns.This work provides new insights into rational design of high-performance heterogeneous photocatalysts and offers a deeper understanding of the mechanism under-lying surface active sites in the photocatalytic NRR process.
基金provided by the Key Program of the National Natural Science Foundation of China(22238007)the National Natural Science Foundation of China(22222810,22208289)Young Elite Scientists Sponsorship Program by CAST(2023QNRC001).
文摘Microbubbles have been widely used in the chemical industry in recent years due to their unique physical and chemical properties.This article provides an overview of the characteristics and main generation methods of microbubbles,including physical,chemical,mechanical,and microfluidic tech-niques.It also explores the applications of microbubbles in the chemical industry,such as gas-liquid reaction intensification, gas separation,mineral flotation, and preparation of high-performance poly olefin materials.By analyzing the current research status of microbubble technology,the future development direction of its application in the chemical industry is discussed.
