Traumatic spinal cord injury often leads to the disintegration of nerve cells and axons,resulting in a substantial accumulation of myelin debris that can persist for years.The abnormal buildup of myelin debris at site...Traumatic spinal cord injury often leads to the disintegration of nerve cells and axons,resulting in a substantial accumulation of myelin debris that can persist for years.The abnormal buildup of myelin debris at sites of injury greatly impedes nerve regeneration,making the clearance of debris within these microenvironments crucial for effective post-spinal cord injury repair.In this review,we comprehensively outline the mechanisms that promote the clearance of myelin debris and myelin metabolism and summarize their roles in spinal cord injury.First,we describe the composition and characteristics of myelin debris and explain its effects on the injury site.Next,we introduce the phagocytic cells involved in myelin debris clearance,including professional phagocytes(macrophages and microglia)and non-professional phagocytes(astrocytes and microvascular endothelial cells),as well as other cells that are also proposed to participate in phagocytosis.Finally,we focus on the pathways and associated targets that enhance myelin debris clearance by phagocytes and promote lipid metabolism following spinal cord injury.Our analysis indicates that myelin debris phagocytosis is not limited to monocyte-derived macrophages,but also involves microglia,astrocytes,and microvascular endothelial cells.By modulating the expression of genes related to phagocytosis and lipid metabolism,it is possible to modulate lipid metabolism disorders and influence inflammatory phenotypes,ultimately affecting the recovery of motor function following spinal cord injury.Additionally,therapies such as targeted mitochondrial transplantation in phagocytic cells,exosome therapy,and repeated trans-spinal magnetic stimulation can effectively enhance the removal of myelin debris,presenting promising potential for future applications.展开更多
All-vanadium flow batteries(VFBs)are one of the most promising large-scale energy storage technologies.Conducting an operando quantitative analysis of the polarizations in VFBs under different conditions is essential ...All-vanadium flow batteries(VFBs)are one of the most promising large-scale energy storage technologies.Conducting an operando quantitative analysis of the polarizations in VFBs under different conditions is essential for developing high power density batteries.Here,we employ an operando decoupling method to quantitatively analyze the polarizations in each electrochemical and chemical reaction of VFBs under different catalytic conditions.Results show that the reduction reaction of V^(3+)presents the largest activation polarization,while the reduction reaction of VO_(2)^(+)primarily contributes to concentration polarizations due to the formation of the intermediate product V_(2)O_(3)^(3+).Additionally,it is found that the widely used electrode catalytic methods,incorporating oxygen functional groups and electrodepositing Bi,not only enhance the reaction kinetics but also exacerbate concentration polarizations simultaneously,especially during the discharge process.Specifically,in the battery with the high oxygen-containing electrodes,the negative side still accounts for the majority of activation loss(75.3%)at 200 mA cm^(-2),but it comes down to 36,9% after catalyzing the negative reactions with bismuth.This work provides an effective way to probe the limiting steps in flow batteries under various working conditions and offers insights for effectively enhancing battery performance for future developments.展开更多
For the uracil-BX3 （X = F, Cl） systems, geometries and binding energies have been calculated by using the Lee-Young-Parr correlation functionals （B3LYP） method of density functional theory （DFT） and the second-o...For the uracil-BX3 （X = F, Cl） systems, geometries and binding energies have been calculated by using the Lee-Young-Parr correlation functionals （B3LYP） method of density functional theory （DFT） and the second-order Moller-Plesset （MP2） method of ab initio at the 6- 311 ＋G^＊ or 6-311 ＋＋G^＊ basis set. Four isomers were found for each system, and then the single-point energy evaluations were performed using the larger basis sets of （6-311 ＋G（2df, p） and aug-cc-pVDZ with DFF method. In the most stable isomer of uracil-BF3 or uracil-BCl3, the boron atom of BX3 （X = F, Cl） connects to the carbonyl oxygen O7 of uracil with a stabilization energy of -46.56 or -31.10 kJ/mol at the B3LYP/6-31 1＋G^＊ level （BSSE corrected）. The analyses for combining interaction between BX3 and uracil with the atom-in-molecule theory （AIM） and natural bond orbital method （NBO） have been performed. The results indicate that all isomers were formed with σ-p type interactions between uracil and BX3, in which the carbonyl oxygen offers its lone pair electrons to the empty p orbital of boron atom and the concomitances of charge transfer from uracil to BX3 occur. Moreover, there exists one or two hydrogen bonds in most isomers of uracil-BX3 system and these hydrogen bonds contribute to the stability of the complex systems. Frequency analysis suggests that the stretching vibration of BX3 undergoes a red shift in complexes. Uracil-BF3 complex is more stable than uracil-BCl3 although the distance of B-O is shorter in the latter. Besides, the conversion mechanisms between different isomers of uracil-BF3 have been obtained.展开更多
A new tetragonal phase of LunSnl0 is obtained from high temperature reaction of the pure elements in a welded tantalum tube. Its crystal structure was established by single-crystal X-ray diffraction. Lu11Sn10 crystall...A new tetragonal phase of LunSnl0 is obtained from high temperature reaction of the pure elements in a welded tantalum tube. Its crystal structure was established by single-crystal X-ray diffraction. Lu11Sn10 crystallizes in the tetragonal space group 14/mmm （No. 139） with a = 11.2953（18）, c = 16.424（4） A, V= 2095.5（7）A3, Z= 4, Mr = 3111.57, Dc = 9.863 g/cm^3, p = 62.897 -1 mm , F（000） = 5124, and the final R = 0.0348 and wR = 0.0894 for 706 observed reflections with 1 〉 2σ（I）. The structure of LullSnl0 may be derived from the HonGel0 structural type. It is isostructural with DyllSn10, featuring a three-dimensional （3D） framework composed of [Sn4] squares and [Sn2] dimers interlinked via Sn-Sn bonds with two types of one-dimensional （1D） tunnels along the c-axis, which are occupied by isolated Sn atoms, [Sn2] dimers and all the Lu atoms Band structure calculation based on density functional theory method indicates that LUllSn10 is metallic.展开更多
A new nickel（Ⅱ） coordination complex [Ni（phen）a].（m-nitrobenzoic acid）2·（H2O） was synthesized by self-assembly of m-nitrobenzoic acid, 1,10-phenanthroline and nickelous perchlorate. It crystallizes in th...A new nickel（Ⅱ） coordination complex [Ni（phen）a].（m-nitrobenzoic acid）2·（H2O） was synthesized by self-assembly of m-nitrobenzoic acid, 1,10-phenanthroline and nickelous perchlorate. It crystallizes in the monoclinic system, space group C2/c, with a = 2.4596（6）, b = 1.2124（3）, c = 1.9824（5） nm, fl = 97.088（5）°, V = 5.866（3） nm3, Dc = 1.474 g/cm3, Z = 4, Mr = 1301.82,μ（MoKa） = 0.417 mm^-1 F（000） = 2688, R = 0.0493 and wR = 0.1025. Structural determination indicates that the nickel（H） ion is coordinated with six nitrogen atoms from three phens, giving a distorted octaheclral coordination geometry. The cyclic voltametric analysis shows that the electron transfer in the electrode reaction is irreversible.展开更多
The concentration and chemical speciation of heavy metals including REEs （rare earth elements）, Th （thorium） and U （uranium） in domestic sludge and electroplating sludge were investigated, and those of the domes...The concentration and chemical speciation of heavy metals including REEs （rare earth elements）, Th （thorium） and U （uranium） in domestic sludge and electroplating sludge were investigated, and those of the domestic sludge were compared with those of natural soil. Removal of heavy metals in electroplating sludge was studied with bio-surfactants （saponin and sophorolipid） by batch and column experiments. The results suggested that heavy metals have greater concentrations and exist as more relatively unstable fraction in sludge than those in Natural soil. Nonionic saponin is more efficient than sophorolipid for the removal of heavy metals from the electroplating sludge, and mainly reacts with carbonate state （i.e., F3） and Fe-Mn oxide state （i.e., F5） fractions. The recovery efficiency of heavy metals in leachates from the electroplate sludge was attained 88%-97%. Saponin can be reused and be a promising and cost-effective material for the removal of heavy metals in sludge.展开更多
Single-atom photocatalysts(SAPCs)have attracted great interests due to their remarkable atom utilization efficiency,excellent activity,and selectivity,yet no application in synchronous biorefinery and water splitting....Single-atom photocatalysts(SAPCs)have attracted great interests due to their remarkable atom utilization efficiency,excellent activity,and selectivity,yet no application in synchronous biorefinery and water splitting.Here,efficient SAPCs based on atomically dispersed Zn atoms on carbon nitride(named Zn-mCN)were produced.Experiments verified that Zn-mCN has widened adsorption range of visible-light and lowered ability of electron-hole recombination,leading to excellent photocatalytic redox activity for synchronous biorefinery and water splitting to co-produce lactic acid(selectivity up to 91.0%)and hydrogen(-15898.8μmolg^(-1)h^(-1)).This system has excellent universality for small-molecule monosaccharides and macromolecular xylan.Poisoning experiments showed that h^(+),1O2,·O_(2)-and·OH can promote the simultaneous production of lactic acid and hydrogen.This work realized full utilization of whole redox reaction and provided a novel strategy for efficient and concomitant production of hydrogen and value-added chemicals from biomass-derived feedstocks aqueous solutions.展开更多
Alcohol oxidation is a widely used green chemical reaction.The reaction process produces flammable and explosive hydrogen,so the design of the reactor must meet stringent safety requirements.Based on the limited exper...Alcohol oxidation is a widely used green chemical reaction.The reaction process produces flammable and explosive hydrogen,so the design of the reactor must meet stringent safety requirements.Based on the limited experimental data,utilizing the traditional numerical method of computational fluid dynamics(CFD)to simulate the gas-liquid two-phase flow reactor can mitigate the risk of danger under varying working conditions.However,the calculation process is highly time-consuming.Therefore,by integrating process simulation,computational fluid dynamics,and deep learning technologies,an intelligent hybrid chemical model based on machine learning was proposed to expedite CFD calculations,enhance the prediction of flow fields,conversion rates,and concentrations inside the reactor,and offer insights for designing and optimizing the reactor for the alcohol oxidation system.The results show that the hybrid model based on the long and short-term memory neural network achieves 99.8%accuracy in conversion rate prediction and 99.9%accuracy in product concentration prediction.Through validation,the hybrid model is accelerated by about 360 times compared with instrumental analysis in conversion rate prediction and about 45 times compared with CFD calculation in concentration distribution prediction.This hybrid model can quickly predict the conversion rate and product concentration distribution in the gas-liquid two-phase flow reactor and provide a model reference for fast prediction and accurate control in the actual chemical production process.展开更多
Developing high-performance narrow-bandgap (NBG) perovskite solar cells based on tin-lead (Sn-Pb) perovskite is critical for the advancement of all-perovskite tandem solar cells. However, the limitations of the device...Developing high-performance narrow-bandgap (NBG) perovskite solar cells based on tin-lead (Sn-Pb) perovskite is critical for the advancement of all-perovskite tandem solar cells. However, the limitations of the device current density and efficiency are magnified by the issues concerning poor carrier transport caused by a substantial number of defects in thick NBG films. This problem is further exacerbated by the quality of film crystallization, which is associated with the rapid and uncontrolled crystallization of Sn-rich perovskite chemistry using the antisolvent approach. We regulate the crystallization of Sn-contained perovskite with a mild gas-quench approach to fabricate a highly crystal-oriented and well-arranged NBG perovskite absorber. This strategy effectively boosts electron transport and light absorption of the NBG perovskite. Consequently, the average power conversion efficiency (PCE) of the NBG perovskite solar cells increases from 19.50% to 21.18%, with the best device achieving an excellent PCE of 21.84%. Furthermore, when combined with a wide-bandgap perovskite subcell to form an all-perovskite tandem solar cell, a PCE of 25.23% is achieved. After being stored in the glovebox for 1000 h, the unencapsulated device maintains over 90% of its initial PCE, demonstrating long-term stability and durability. This work presents a promising approach for developing high-efficiency NBG perovskite solar cells.展开更多
The poor electrical conductivity of metal-organic frameworks(MOFs)limits their electrocatalytic performance in the oxygen evolution reaction(OER).In this study,a Py@Co-MOF composite material based on pyrene(Py)molecul...The poor electrical conductivity of metal-organic frameworks(MOFs)limits their electrocatalytic performance in the oxygen evolution reaction(OER).In this study,a Py@Co-MOF composite material based on pyrene(Py)molecules and{[Co2(BINDI)(DMA)_(2)]·DMA}_(n)(Co-MOF,H4BINDI=N,N'-bis(5-isophthalic acid)naphthalenediimide,DMA=N,N-dimethylacetamide)was synthesized via a one-pot method,leveragingπ-πinteractions between pyrene and Co-MOF to modulate electrical conductivity.Results demonstrate that the Py@Co-MOF catalyst exhibited significantly enhanced OER performance compared to pure Co-MOF or pyrene-based electrodes,achieving an overpotential of 246 mV at a current density of 10 mA·cm^(-2) along with excellent stability.Density functional theory(DFT)calculations reveal that the formation of O*in the second step is the rate-determining step(RDS)during the OER process on Co-MOF,with an energy barrier of 0.85 eV due to the weak adsorption affinity of the OH*intermediate for Co sites.CCDC:2419276.展开更多
The electrochemical conversion of carbon dioxide into valuable products is pivotal for maintaining the global carbon cycle and mitigating global warming.This review explores the advancements in electrochemical CO_(2) ...The electrochemical conversion of carbon dioxide into valuable products is pivotal for maintaining the global carbon cycle and mitigating global warming.This review explores the advancements in electrochemical CO_(2) conversion,particularly focusing on producing methanol,ethanol,and n-propanol using various catalysts such as metals,metal oxides,metal alloys,and metal organic frameworks.Additionally,it covers the photoelectrochemical(PEC)conversion of CO_(2) into alcohols.The primary objective is to identify efficient electrocatalysts for ethanol,methanol,and n-propanol production,prioritizing selectivity,stability,Faradaic efficiency(FE),and current density.Notable catalysts include PtxZn nanoalloys,which exhibit an FE of~81.4% for methanol production,and trimetallic Pt/Pb/Zn nanoalloys,aimed at reducing Pt costs while enhancing catalyst stability and durability.Metal oxide catalysts like thin film Cu_(2)O/CuO on nickel foam and Cu_(2)O/ZnO achieve FE values of~38% and~16.6% for methanol production,respectively.Copper-based metal-organic frameworks,such as Cu@Cu_(2)O,demonstrate an FE of~45% for methanol production.Similarly,Ag_(0.14)/Cu_(0.86) and Cu-Zn alloys exhibit FEs of~63% and~46.6%,respectively,for ethanol production.Notably,n-propanol production via Pd–Cu alloy and graphene/ZnO/Cu_(2)O yields FEs of~13.7% and~23%,respectively.Furthermore,the review discusses recent advancements in PEC reactor design,photoelectrodes,reaction mechanisms,and catalyst durability.By evaluating the efficiency of these devices in liquid fuel production,the review addresses challenges and prospects in CO_(2) conversion for obtaining various valuable products.展开更多
A new 3D Ag（I） coordination polymer, [Ag8（btc）2（bpp）2]n（1, H4btc = biphenyl- 2,2ˊ,4,4ˊ-tetracarboxylic acid, bpp = 1,2-bis（4-pyridyl）propane）, has been hydrothermally synthesi- zed and characterized by sin...A new 3D Ag（I） coordination polymer, [Ag8（btc）2（bpp）2]n（1, H4btc = biphenyl- 2,2ˊ,4,4ˊ-tetracarboxylic acid, bpp = 1,2-bis（4-pyridyl）propane）, has been hydrothermally synthesi- zed and characterized by single-crystal X-ray diffraction analysis, elemental analysis and IR spectroscopy. Complex 1 crystallizes in the triclinic system, space group P1 with a = 13.4899（8）, b = 13.4928（8）, c = 16.4575（10） , α = 102.7640（10）, β = 108.8100（10）, γ = 101.4940（10）°, V = 2644.1（3） 3, Z = 2, Dc = 2.401 Mg·m-3, μ = 2.978 mm-1, F（000） = 1840, the final R = 0.0481 and wR = 0.0955 for 6794 observed reflections with I 〉 2σ（I）. Complex 1 features a 3D framework formed by Ag（I）-carboxylate chains containing [Ag16（COO）16] secondary building block. Furthermore, thermal stability and electrochemical property of 1 are also investigated in detail.展开更多
In this paper, gas chromatography-mass spectrometry （GS-MS） was used to build the standard fingerprint of volatile oil from Rosa multiflora Thunb. from 12 different habitats. Fourteen components in the volatile oil ...In this paper, gas chromatography-mass spectrometry （GS-MS） was used to build the standard fingerprint of volatile oil from Rosa multiflora Thunb. from 12 different habitats. Fourteen components in the volatile oil were identified as the indicator components ofR. multiflora, of which one was selected as the standard. The GC analysis conditions used for fingerprinting afford a very good separating effect. The similarity of the 12 volatile oils from R. multiflora Thunb. was more than 0.84, and the precision, stability and repeatability of the fingerprints were quite good. It could be concluded that the fingerprints can be used as the standard and as a quality control method for medicinal materials from R. multiflora Thunb..展开更多
In order to investigate the isotopic and chemical characteristics of lagoon waters in Niigata Prefecture in recent years, oxygen and hydrogen stable isotope ratios （i.e., 8180 and 6D）, the concentrations of DOC （di...In order to investigate the isotopic and chemical characteristics of lagoon waters in Niigata Prefecture in recent years, oxygen and hydrogen stable isotope ratios （i.e., 8180 and 6D）, the concentrations of DOC （dissolved organic carbon）, DO （dissolved oxygen） and pH, etc. in water samples of Sakata and Toyanogata were measured. Samples were generally taken monthly at the fixed sampling points from these lagoons. Consequently, the following matters have been mainly clarified： （1） ~D value of water samples in Sakata was generally larger than that in Toyanogata similarly to the case of ~180, though remarkable large difference among samples was not found; （2） the pH value of lagoon water samples is almost 6.5-8.5 （which is generally larger than that of river water）, and pH at the spot of SI （downstream point of Lower Lagoon （Shitakata）） is remarkably high （9.0-9.5）; （3） Lagoon water has the chemical characteristics contrasting to groundwater with a focus on river water from the viewpoint of pH （acidity or alkalinity） and DO. These matters can be closely related to the biological activity such as photosynthesis due to aquatic plant and phytoplankton and the activity of Crustacea plankton etc. in lagoon.展开更多
A two-component waterborne polyurethane(2K-WPU) was prepared by mixing water-soluble acrylic resin and hexamethylene diisocyanate biuret, and then diluted for phase inversion with water. Compared with water-soluble ac...A two-component waterborne polyurethane(2K-WPU) was prepared by mixing water-soluble acrylic resin and hexamethylene diisocyanate biuret, and then diluted for phase inversion with water. Compared with water-soluble acrylic resin, the phase inversion of 2K-WPU occurs at lower water content. It is indicated by TEM that 2K-WPU parti-cles show a core-shell structure, in which HDI biuret is encapsulated by hydrophilic acrylic resin. 2K-WPU emulsion with HDI biuret has larger particle size and narrower distribution index, while for 2K-WPU emulsion with HDI iso-cyanurate, the latex not only has large particle size, but also has two-peak distribution. FTIR shows that the reaction be-tween HDI biuret and acrylic resin can complete in 12h. In addition, studies on effect of composition of acrylic resin on performance of 2K-WPU show that narrowing the polar difference between water-soluble acrylic resin and HDI biuret and improving the miscibility of two components are the key to prepare the transparent and high gloss films with high crosslinking density.展开更多
Metal‐organic framework MIL‐100(Fe)and g‐C3N4 heterojunctions(MG‐x,x=5%,10%,20%,and 30%,x is the mass fraction of MIL‐100(Fe)in the hybrids)were facilely fabricated through ball‐milling and annealing,and charact...Metal‐organic framework MIL‐100(Fe)and g‐C3N4 heterojunctions(MG‐x,x=5%,10%,20%,and 30%,x is the mass fraction of MIL‐100(Fe)in the hybrids)were facilely fabricated through ball‐milling and annealing,and characterized by powder X‐ray diffraction,Fourier transform infrared spectroscopy,thermogravimetric analysis,transmission electron microscopy,UV‐visible diffuse‐reflectance spectrometry,and photoluminescence emission spectrometry.The photocatalytic activities of the series of MG‐x heterojunctions toward Cr(VI)reduction and diclofenac sodium degradation were tested upon irradiation with simulated sunlight.The influence of different organic compounds(ethanol,citric acid,oxalic acid,and diclofenac sodium)as hole scavengers and the pH values(2,3,4,6,and 8)on the photocatalytic activities of the series of MG‐x heterojunctions was investigated.MG‐20%showed superior photocatalytic Cr(VI)reduction and diclofenac sodium degradation performance than did the individual MIL‐100(Fe)and g‐C3N4 because of the improved separation of photoinduced electron‐hole charges,which was clarified via photoluminescence emission and electrochemical data.Moreover,the MG‐x exhibited good reusability and stability after several runs.展开更多
Volatile organic compounds(VOCs),methane,carbon monoxide,soot,automotive exhaust,and nitrogen oxides are harmful to the atmosphere and human health.It is urgent to strictly control their emissions.Heterogeneous cataly...Volatile organic compounds(VOCs),methane,carbon monoxide,soot,automotive exhaust,and nitrogen oxides are harmful to the atmosphere and human health.It is urgent to strictly control their emissions.Heterogeneous catalysis is an effective pathway for the removal of these pollutants,and the critical issue is the development of novel and high-performance catalysts.In this review,we briefly summarize the preparation methods,physicochemical properties,catalytic activities,and related reaction mechanisms for the above pollutants removal of the rare earth oxides,mixed rare earth oxide,rare earth oxidesupported noble metal,and mixed rare earth oxide-supported noble metal catalysts that have been investigated by our group and other researchers.It was found that catalytic performance was associated with the factors,such as specific surface area,pore structure,particle size and dispersion,adsorbed oxygen species concentration,reducibility,reactant activation ability or interaction between metal nanoparticles and support.Furthermore,we also envision the development trend of such a topic in future work.展开更多
The separation of gas molecules with similar physicochemical properties is of high importance but practically entails a substantial energy penalty in chemical industry. Meanwhile, clean energy gases such as H_2 and CH...The separation of gas molecules with similar physicochemical properties is of high importance but practically entails a substantial energy penalty in chemical industry. Meanwhile, clean energy gases such as H_2 and CH_4 are considered as promising candidates for the replacement of traditional fossil fuels. However, the technologies for the storage of these gases are still immature. In addition, the release of anthropogenic toxic gases into the atmosphere is a worldwide threat of growing concern. Both in academia and industry, considerable research efforts have been devoted to developing advanced porous materials for the effective and energy-efficient separation, storage, or capture of the related gases. In contrast to conventional inorganic porous materials such as zeolites and activated carbons, metal–organic frameworks(MOFs) are considered as a type of promising materials for gas separation and storage. In this contribution, we review the recent research advance of MOFs in some relevant applications, including CO_2 capture, O_2 purification, separation of light hydrocarbons, separation of noble gases, storage of gases(CH_4,H_2, and C_2 H_2) for energy, and removal of some gaseous air pollutants(NH_3, NO_2, and SO_2). Finally, an outlook regarding the challenges of the future research of MOFs in these directions is given.展开更多
A reliable ultrasound-assisted extraction （UAE） method combined with HPLC-UV for quantification of eight active alkaloids in fruits of Macleaya cordata （Willd） R. Br. was developed. The optimization conditions of ...A reliable ultrasound-assisted extraction （UAE） method combined with HPLC-UV for quantification of eight active alkaloids in fruits of Macleaya cordata （Willd） R. Br. was developed. The optimization conditions of UAE were obtained by using Box-Behnken design of response surface methodology. Chromatography was carried out using a Kromasil C18 column by gradient elution with 0.1% phosphoric acid aqueous solution for HPLC-UV. All calibration curves showed good linear correlation coefficients （R^2〉0.999 6） and recoveries （from 97.3% to 104.9%） were acceptable. 1,1-diphenyl-2-picrylhydrazyl （DPPH） method was employed to test the antioxidant activity of the extract from the samples. The proposed method was successfully applied to quantifying eight components in nine samples of M.cordata, and significant variations of alkaloid contents and antioxidant aetivity of the samples from different habitats were demonstrated. It presents a powerful proof for the selection of the best sources to extract eight kinds of alkaloids.展开更多
The nV‐MCM‐41 catalysts were prepared by one‐step hydrothermal synthesis and applied to the oxidative dehydrogenation of propane（ODHP） in the presence of CO2. Several state‐of‐the‐art char‐acterization method...The nV‐MCM‐41 catalysts were prepared by one‐step hydrothermal synthesis and applied to the oxidative dehydrogenation of propane（ODHP） in the presence of CO2. Several state‐of‐the‐art char‐acterization methods were performed to explore the correlation between catalytic performance and the physicochemical characterizations of the catalysts. Because moderate amounts of V species were introduced into the framework of MCM‐41, the catalyst maintained a large specific surface area, a highly ordered mesoporous structure, and highly dispersed V active sites（monomeric and dimeric V oxide species）, while the high‐vanadium‐doping catalysts caused an enhancement in the number of acidic sites and V2O5 crystallites. The ODHP reaction showed that the 6.8 V‐MCM‐41（V content 6.8 wt%） catalyst exhibits high activity and stability, and the C3H8/CO2 molar ratio（1：4） was suitable. The promoting effect of CO2 on the oxidative dehydrogenation of ODHP was demonstrated as the reaction coupling mechanism and ＂lattice oxygen＂ mechanism.展开更多
基金supported by the National Natural Science Foundation of China,Nos.82271411(to RG),51803072(to WL)the International Cooperative Project of Talent Cultivation“Xinghai Project”at the China-Japan Union Hospital of Jilin University,No.XHLH202404(to WL)+1 种基金the Science and Technology Development Plan of Jilin Province,No.YDZJ202201ZYTS038(to WL)Jilin Provincial Finance Program,No.2022SCZ10(to WL)。
文摘Traumatic spinal cord injury often leads to the disintegration of nerve cells and axons,resulting in a substantial accumulation of myelin debris that can persist for years.The abnormal buildup of myelin debris at sites of injury greatly impedes nerve regeneration,making the clearance of debris within these microenvironments crucial for effective post-spinal cord injury repair.In this review,we comprehensively outline the mechanisms that promote the clearance of myelin debris and myelin metabolism and summarize their roles in spinal cord injury.First,we describe the composition and characteristics of myelin debris and explain its effects on the injury site.Next,we introduce the phagocytic cells involved in myelin debris clearance,including professional phagocytes(macrophages and microglia)and non-professional phagocytes(astrocytes and microvascular endothelial cells),as well as other cells that are also proposed to participate in phagocytosis.Finally,we focus on the pathways and associated targets that enhance myelin debris clearance by phagocytes and promote lipid metabolism following spinal cord injury.Our analysis indicates that myelin debris phagocytosis is not limited to monocyte-derived macrophages,but also involves microglia,astrocytes,and microvascular endothelial cells.By modulating the expression of genes related to phagocytosis and lipid metabolism,it is possible to modulate lipid metabolism disorders and influence inflammatory phenotypes,ultimately affecting the recovery of motor function following spinal cord injury.Additionally,therapies such as targeted mitochondrial transplantation in phagocytic cells,exosome therapy,and repeated trans-spinal magnetic stimulation can effectively enhance the removal of myelin debris,presenting promising potential for future applications.
基金supported by the Guangdong Major Project of Basic and Applied Basic Research(2023B0303000002)the National Natural Science Foundation of China(No.52206089)+3 种基金the Guangdong Basic and Applied Basic Research Foundation(2024A1515010288,2023B1515120005)the Natural Science Foundation of Shenzhen(JCYJ20230807093315033)the Shenzhen Engineering Research Center,Southern University of Science and Technology(No.XMHT20230208003)high level of special funds(G03034K001)。
文摘All-vanadium flow batteries(VFBs)are one of the most promising large-scale energy storage technologies.Conducting an operando quantitative analysis of the polarizations in VFBs under different conditions is essential for developing high power density batteries.Here,we employ an operando decoupling method to quantitatively analyze the polarizations in each electrochemical and chemical reaction of VFBs under different catalytic conditions.Results show that the reduction reaction of V^(3+)presents the largest activation polarization,while the reduction reaction of VO_(2)^(+)primarily contributes to concentration polarizations due to the formation of the intermediate product V_(2)O_(3)^(3+).Additionally,it is found that the widely used electrode catalytic methods,incorporating oxygen functional groups and electrodepositing Bi,not only enhance the reaction kinetics but also exacerbate concentration polarizations simultaneously,especially during the discharge process.Specifically,in the battery with the high oxygen-containing electrodes,the negative side still accounts for the majority of activation loss(75.3%)at 200 mA cm^(-2),but it comes down to 36,9% after catalyzing the negative reactions with bismuth.This work provides an effective way to probe the limiting steps in flow batteries under various working conditions and offers insights for effectively enhancing battery performance for future developments.
基金This work was supported by the National Natural Science Foundation of China (No. 20171031)
文摘For the uracil-BX3 （X = F, Cl） systems, geometries and binding energies have been calculated by using the Lee-Young-Parr correlation functionals （B3LYP） method of density functional theory （DFT） and the second-order Moller-Plesset （MP2） method of ab initio at the 6- 311 ＋G^＊ or 6-311 ＋＋G^＊ basis set. Four isomers were found for each system, and then the single-point energy evaluations were performed using the larger basis sets of （6-311 ＋G（2df, p） and aug-cc-pVDZ with DFF method. In the most stable isomer of uracil-BF3 or uracil-BCl3, the boron atom of BX3 （X = F, Cl） connects to the carbonyl oxygen O7 of uracil with a stabilization energy of -46.56 or -31.10 kJ/mol at the B3LYP/6-31 1＋G^＊ level （BSSE corrected）. The analyses for combining interaction between BX3 and uracil with the atom-in-molecule theory （AIM） and natural bond orbital method （NBO） have been performed. The results indicate that all isomers were formed with σ-p type interactions between uracil and BX3, in which the carbonyl oxygen offers its lone pair electrons to the empty p orbital of boron atom and the concomitances of charge transfer from uracil to BX3 occur. Moreover, there exists one or two hydrogen bonds in most isomers of uracil-BX3 system and these hydrogen bonds contribute to the stability of the complex systems. Frequency analysis suggests that the stretching vibration of BX3 undergoes a red shift in complexes. Uracil-BF3 complex is more stable than uracil-BCl3 although the distance of B-O is shorter in the latter. Besides, the conversion mechanisms between different isomers of uracil-BF3 have been obtained.
基金Supported by the National Natural Science Foundation of China (No. 21101075 and 21201081)the research foundation for excellent young and middle-aged scientists of Shandong Province (No. BS2011CL009 and BS2012CL008)+2 种基金the Science & Research Program foundation of high education of Shandong Province (No. J11LB52)the Rehearsal National Foundation of Jining University (Nos. 2011YYJJ06 and 2011YYJJ07)the Youths Science Foundation of Jining University (No. 2011QNKJ07)
文摘A new tetragonal phase of LunSnl0 is obtained from high temperature reaction of the pure elements in a welded tantalum tube. Its crystal structure was established by single-crystal X-ray diffraction. Lu11Sn10 crystallizes in the tetragonal space group 14/mmm （No. 139） with a = 11.2953（18）, c = 16.424（4） A, V= 2095.5（7）A3, Z= 4, Mr = 3111.57, Dc = 9.863 g/cm^3, p = 62.897 -1 mm , F（000） = 5124, and the final R = 0.0348 and wR = 0.0894 for 706 observed reflections with 1 〉 2σ（I）. The structure of LullSnl0 may be derived from the HonGel0 structural type. It is isostructural with DyllSn10, featuring a three-dimensional （3D） framework composed of [Sn4] squares and [Sn2] dimers interlinked via Sn-Sn bonds with two types of one-dimensional （1D） tunnels along the c-axis, which are occupied by isolated Sn atoms, [Sn2] dimers and all the Lu atoms Band structure calculation based on density functional theory method indicates that LUllSn10 is metallic.
基金the Foundation of Education Committee of Hunan Province (06C195) the Research Award Fund for Outstanding Young Teachers of Hengyang Normal University (2006)
文摘A new nickel（Ⅱ） coordination complex [Ni（phen）a].（m-nitrobenzoic acid）2·（H2O） was synthesized by self-assembly of m-nitrobenzoic acid, 1,10-phenanthroline and nickelous perchlorate. It crystallizes in the monoclinic system, space group C2/c, with a = 2.4596（6）, b = 1.2124（3）, c = 1.9824（5） nm, fl = 97.088（5）°, V = 5.866（3） nm3, Dc = 1.474 g/cm3, Z = 4, Mr = 1301.82,μ（MoKa） = 0.417 mm^-1 F（000） = 2688, R = 0.0493 and wR = 0.1025. Structural determination indicates that the nickel（H） ion is coordinated with six nitrogen atoms from three phens, giving a distorted octaheclral coordination geometry. The cyclic voltametric analysis shows that the electron transfer in the electrode reaction is irreversible.
文摘The concentration and chemical speciation of heavy metals including REEs （rare earth elements）, Th （thorium） and U （uranium） in domestic sludge and electroplating sludge were investigated, and those of the domestic sludge were compared with those of natural soil. Removal of heavy metals in electroplating sludge was studied with bio-surfactants （saponin and sophorolipid） by batch and column experiments. The results suggested that heavy metals have greater concentrations and exist as more relatively unstable fraction in sludge than those in Natural soil. Nonionic saponin is more efficient than sophorolipid for the removal of heavy metals from the electroplating sludge, and mainly reacts with carbonate state （i.e., F3） and Fe-Mn oxide state （i.e., F5） fractions. The recovery efficiency of heavy metals in leachates from the electroplate sludge was attained 88%-97%. Saponin can be reused and be a promising and cost-effective material for the removal of heavy metals in sludge.
基金supported by the National Natural Science Foundation of China(No.22008018)China Postdoctoral Science Foundation(No.2020M670716)+5 种基金the Natural Science Foundation of Liaoning Province,China(No.2020-MS-272)the Foundation of Guangxi Key Laboratory of Clean Pulp&Papermaking and Pollution Control,College of Light Industry and Food Engineering,Guangxi University(No.2021KF08)Dalian City Outstanding Talent Project(No.2019RD13)the Start-up Fund for Doctoral Research of Dalian Polytechnic University(No.2020–07)the Foundation of State Key Laboratory of Biobased Material and Green Papermaking,Qilu University of Technology,Shandong Academy of Sciences(No.KF201914)the Foundation of Key Laboratory of State Forestry and Grassland Administration for Plant Fiber Functional Materials(No.2020KFJJ06).
文摘Single-atom photocatalysts(SAPCs)have attracted great interests due to their remarkable atom utilization efficiency,excellent activity,and selectivity,yet no application in synchronous biorefinery and water splitting.Here,efficient SAPCs based on atomically dispersed Zn atoms on carbon nitride(named Zn-mCN)were produced.Experiments verified that Zn-mCN has widened adsorption range of visible-light and lowered ability of electron-hole recombination,leading to excellent photocatalytic redox activity for synchronous biorefinery and water splitting to co-produce lactic acid(selectivity up to 91.0%)and hydrogen(-15898.8μmolg^(-1)h^(-1)).This system has excellent universality for small-molecule monosaccharides and macromolecular xylan.Poisoning experiments showed that h^(+),1O2,·O_(2)-and·OH can promote the simultaneous production of lactic acid and hydrogen.This work realized full utilization of whole redox reaction and provided a novel strategy for efficient and concomitant production of hydrogen and value-added chemicals from biomass-derived feedstocks aqueous solutions.
基金the support from the National Natural Science Foundation of China(22478429)the Special Project Fund of Taishan-Scholars(tsqn202408101)+3 种基金the Natural Science Foundation of Shandong Province(ZR2023YQ009)CNPC Innovation Found(2024DQ02-0504)Fundamental Research Funds for the Central Universities,Ocean University of China(202364004)the State Key Laboratory of Heavy Oil Processing(SKLHOP202403003)。
文摘Alcohol oxidation is a widely used green chemical reaction.The reaction process produces flammable and explosive hydrogen,so the design of the reactor must meet stringent safety requirements.Based on the limited experimental data,utilizing the traditional numerical method of computational fluid dynamics(CFD)to simulate the gas-liquid two-phase flow reactor can mitigate the risk of danger under varying working conditions.However,the calculation process is highly time-consuming.Therefore,by integrating process simulation,computational fluid dynamics,and deep learning technologies,an intelligent hybrid chemical model based on machine learning was proposed to expedite CFD calculations,enhance the prediction of flow fields,conversion rates,and concentrations inside the reactor,and offer insights for designing and optimizing the reactor for the alcohol oxidation system.The results show that the hybrid model based on the long and short-term memory neural network achieves 99.8%accuracy in conversion rate prediction and 99.9%accuracy in product concentration prediction.Through validation,the hybrid model is accelerated by about 360 times compared with instrumental analysis in conversion rate prediction and about 45 times compared with CFD calculation in concentration distribution prediction.This hybrid model can quickly predict the conversion rate and product concentration distribution in the gas-liquid two-phase flow reactor and provide a model reference for fast prediction and accurate control in the actual chemical production process.
基金supported by the National Key Research and Development Program of China(Grant No.2020YFB1506400)the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDB43000000)+3 种基金the CAS Project for Young Scientists in Basic Research(YSBR-090)the National Natural Science Foundation of China(Contract Nos.U20A20206,51972300,62274155,and 62304219)support from the Youth Innovation Promotion Association,the Chi-nese Academy of Sciences(No.2020114)Beijing Natural Sci-ence Foundation(Grant No.JQ24029).
文摘Developing high-performance narrow-bandgap (NBG) perovskite solar cells based on tin-lead (Sn-Pb) perovskite is critical for the advancement of all-perovskite tandem solar cells. However, the limitations of the device current density and efficiency are magnified by the issues concerning poor carrier transport caused by a substantial number of defects in thick NBG films. This problem is further exacerbated by the quality of film crystallization, which is associated with the rapid and uncontrolled crystallization of Sn-rich perovskite chemistry using the antisolvent approach. We regulate the crystallization of Sn-contained perovskite with a mild gas-quench approach to fabricate a highly crystal-oriented and well-arranged NBG perovskite absorber. This strategy effectively boosts electron transport and light absorption of the NBG perovskite. Consequently, the average power conversion efficiency (PCE) of the NBG perovskite solar cells increases from 19.50% to 21.18%, with the best device achieving an excellent PCE of 21.84%. Furthermore, when combined with a wide-bandgap perovskite subcell to form an all-perovskite tandem solar cell, a PCE of 25.23% is achieved. After being stored in the glovebox for 1000 h, the unencapsulated device maintains over 90% of its initial PCE, demonstrating long-term stability and durability. This work presents a promising approach for developing high-efficiency NBG perovskite solar cells.
文摘The poor electrical conductivity of metal-organic frameworks(MOFs)limits their electrocatalytic performance in the oxygen evolution reaction(OER).In this study,a Py@Co-MOF composite material based on pyrene(Py)molecules and{[Co2(BINDI)(DMA)_(2)]·DMA}_(n)(Co-MOF,H4BINDI=N,N'-bis(5-isophthalic acid)naphthalenediimide,DMA=N,N-dimethylacetamide)was synthesized via a one-pot method,leveragingπ-πinteractions between pyrene and Co-MOF to modulate electrical conductivity.Results demonstrate that the Py@Co-MOF catalyst exhibited significantly enhanced OER performance compared to pure Co-MOF or pyrene-based electrodes,achieving an overpotential of 246 mV at a current density of 10 mA·cm^(-2) along with excellent stability.Density functional theory(DFT)calculations reveal that the formation of O*in the second step is the rate-determining step(RDS)during the OER process on Co-MOF,with an energy barrier of 0.85 eV due to the weak adsorption affinity of the OH*intermediate for Co sites.CCDC:2419276.
基金the financial support from National Science Centre Poland(NCN)based on the decision number UMO-2021/43/D/ST5/00824financial support of research project supported by the program“Excellence Initiative-Research University”for the AGH University of Krakow.
文摘The electrochemical conversion of carbon dioxide into valuable products is pivotal for maintaining the global carbon cycle and mitigating global warming.This review explores the advancements in electrochemical CO_(2) conversion,particularly focusing on producing methanol,ethanol,and n-propanol using various catalysts such as metals,metal oxides,metal alloys,and metal organic frameworks.Additionally,it covers the photoelectrochemical(PEC)conversion of CO_(2) into alcohols.The primary objective is to identify efficient electrocatalysts for ethanol,methanol,and n-propanol production,prioritizing selectivity,stability,Faradaic efficiency(FE),and current density.Notable catalysts include PtxZn nanoalloys,which exhibit an FE of~81.4% for methanol production,and trimetallic Pt/Pb/Zn nanoalloys,aimed at reducing Pt costs while enhancing catalyst stability and durability.Metal oxide catalysts like thin film Cu_(2)O/CuO on nickel foam and Cu_(2)O/ZnO achieve FE values of~38% and~16.6% for methanol production,respectively.Copper-based metal-organic frameworks,such as Cu@Cu_(2)O,demonstrate an FE of~45% for methanol production.Similarly,Ag_(0.14)/Cu_(0.86) and Cu-Zn alloys exhibit FEs of~63% and~46.6%,respectively,for ethanol production.Notably,n-propanol production via Pd–Cu alloy and graphene/ZnO/Cu_(2)O yields FEs of~13.7% and~23%,respectively.Furthermore,the review discusses recent advancements in PEC reactor design,photoelectrodes,reaction mechanisms,and catalyst durability.By evaluating the efficiency of these devices in liquid fuel production,the review addresses challenges and prospects in CO_(2) conversion for obtaining various valuable products.
基金supported by the National Natural Science Foundation of China(No.21373178)the Natural Scientific Research Foundation of Shaanxi Provincial Education Office of China(No.13JS124)
文摘A new 3D Ag（I） coordination polymer, [Ag8（btc）2（bpp）2]n（1, H4btc = biphenyl- 2,2ˊ,4,4ˊ-tetracarboxylic acid, bpp = 1,2-bis（4-pyridyl）propane）, has been hydrothermally synthesi- zed and characterized by single-crystal X-ray diffraction analysis, elemental analysis and IR spectroscopy. Complex 1 crystallizes in the triclinic system, space group P1 with a = 13.4899（8）, b = 13.4928（8）, c = 16.4575（10） , α = 102.7640（10）, β = 108.8100（10）, γ = 101.4940（10）°, V = 2644.1（3） 3, Z = 2, Dc = 2.401 Mg·m-3, μ = 2.978 mm-1, F（000） = 1840, the final R = 0.0481 and wR = 0.0955 for 6794 observed reflections with I 〉 2σ（I）. Complex 1 features a 3D framework formed by Ag（I）-carboxylate chains containing [Ag16（COO）16] secondary building block. Furthermore, thermal stability and electrochemical property of 1 are also investigated in detail.
文摘In this paper, gas chromatography-mass spectrometry （GS-MS） was used to build the standard fingerprint of volatile oil from Rosa multiflora Thunb. from 12 different habitats. Fourteen components in the volatile oil were identified as the indicator components ofR. multiflora, of which one was selected as the standard. The GC analysis conditions used for fingerprinting afford a very good separating effect. The similarity of the 12 volatile oils from R. multiflora Thunb. was more than 0.84, and the precision, stability and repeatability of the fingerprints were quite good. It could be concluded that the fingerprints can be used as the standard and as a quality control method for medicinal materials from R. multiflora Thunb..
文摘In order to investigate the isotopic and chemical characteristics of lagoon waters in Niigata Prefecture in recent years, oxygen and hydrogen stable isotope ratios （i.e., 8180 and 6D）, the concentrations of DOC （dissolved organic carbon）, DO （dissolved oxygen） and pH, etc. in water samples of Sakata and Toyanogata were measured. Samples were generally taken monthly at the fixed sampling points from these lagoons. Consequently, the following matters have been mainly clarified： （1） ~D value of water samples in Sakata was generally larger than that in Toyanogata similarly to the case of ~180, though remarkable large difference among samples was not found; （2） the pH value of lagoon water samples is almost 6.5-8.5 （which is generally larger than that of river water）, and pH at the spot of SI （downstream point of Lower Lagoon （Shitakata）） is remarkably high （9.0-9.5）; （3） Lagoon water has the chemical characteristics contrasting to groundwater with a focus on river water from the viewpoint of pH （acidity or alkalinity） and DO. These matters can be closely related to the biological activity such as photosynthesis due to aquatic plant and phytoplankton and the activity of Crustacea plankton etc. in lagoon.
文摘A two-component waterborne polyurethane(2K-WPU) was prepared by mixing water-soluble acrylic resin and hexamethylene diisocyanate biuret, and then diluted for phase inversion with water. Compared with water-soluble acrylic resin, the phase inversion of 2K-WPU occurs at lower water content. It is indicated by TEM that 2K-WPU parti-cles show a core-shell structure, in which HDI biuret is encapsulated by hydrophilic acrylic resin. 2K-WPU emulsion with HDI biuret has larger particle size and narrower distribution index, while for 2K-WPU emulsion with HDI iso-cyanurate, the latex not only has large particle size, but also has two-peak distribution. FTIR shows that the reaction be-tween HDI biuret and acrylic resin can complete in 12h. In addition, studies on effect of composition of acrylic resin on performance of 2K-WPU show that narrowing the polar difference between water-soluble acrylic resin and HDI biuret and improving the miscibility of two components are the key to prepare the transparent and high gloss films with high crosslinking density.
基金supported by the National Natural Science Foundation of China(51578034,51878023)the Great Wall Scholars Training Program Project of Beijing Municipality Universities(CIT&TCD20180323)+3 种基金the Project of Construction of Innovation Teams and Teacher Career Development for Universities and Colleges Under Beijing Municipality(IDHT20170508)the Beijing Talent Project(2017A38)the Fundamental Research Funds for Beijing Universities(X18075/X18076/X18124/X18125/X18276)the Scientific Research Foundation of Beijing University of Civil Engineering and Architecture(KYJJ2017033/KYJJ2017008)~~
文摘Metal‐organic framework MIL‐100(Fe)and g‐C3N4 heterojunctions(MG‐x,x=5%,10%,20%,and 30%,x is the mass fraction of MIL‐100(Fe)in the hybrids)were facilely fabricated through ball‐milling and annealing,and characterized by powder X‐ray diffraction,Fourier transform infrared spectroscopy,thermogravimetric analysis,transmission electron microscopy,UV‐visible diffuse‐reflectance spectrometry,and photoluminescence emission spectrometry.The photocatalytic activities of the series of MG‐x heterojunctions toward Cr(VI)reduction and diclofenac sodium degradation were tested upon irradiation with simulated sunlight.The influence of different organic compounds(ethanol,citric acid,oxalic acid,and diclofenac sodium)as hole scavengers and the pH values(2,3,4,6,and 8)on the photocatalytic activities of the series of MG‐x heterojunctions was investigated.MG‐20%showed superior photocatalytic Cr(VI)reduction and diclofenac sodium degradation performance than did the individual MIL‐100(Fe)and g‐C3N4 because of the improved separation of photoinduced electron‐hole charges,which was clarified via photoluminescence emission and electrochemical data.Moreover,the MG‐x exhibited good reusability and stability after several runs.
基金Project supported by National Natural Science Foundation of China(21677004,21876006,21622701)National Natural Science Committee of China-Liaoning Provincial People’s Government Joint Fund(U1908204)Foundation on the Creative Research Team Construction Promotion Project of Beijing Municipal Institutions(IDHT20190503)。
文摘Volatile organic compounds(VOCs),methane,carbon monoxide,soot,automotive exhaust,and nitrogen oxides are harmful to the atmosphere and human health.It is urgent to strictly control their emissions.Heterogeneous catalysis is an effective pathway for the removal of these pollutants,and the critical issue is the development of novel and high-performance catalysts.In this review,we briefly summarize the preparation methods,physicochemical properties,catalytic activities,and related reaction mechanisms for the above pollutants removal of the rare earth oxides,mixed rare earth oxide,rare earth oxidesupported noble metal,and mixed rare earth oxide-supported noble metal catalysts that have been investigated by our group and other researchers.It was found that catalytic performance was associated with the factors,such as specific surface area,pore structure,particle size and dispersion,adsorbed oxygen species concentration,reducibility,reactant activation ability or interaction between metal nanoparticles and support.Furthermore,we also envision the development trend of such a topic in future work.
基金supported from the Natural Science Foundation of China (Grant Nos. 21771012, 21601008 and 21576006)the National Natural Science Fund for Innovative Research Groups (Grant No. 51621003)the China Postdoctoral Science Foundation (Grant No. 2016M600879)
文摘The separation of gas molecules with similar physicochemical properties is of high importance but practically entails a substantial energy penalty in chemical industry. Meanwhile, clean energy gases such as H_2 and CH_4 are considered as promising candidates for the replacement of traditional fossil fuels. However, the technologies for the storage of these gases are still immature. In addition, the release of anthropogenic toxic gases into the atmosphere is a worldwide threat of growing concern. Both in academia and industry, considerable research efforts have been devoted to developing advanced porous materials for the effective and energy-efficient separation, storage, or capture of the related gases. In contrast to conventional inorganic porous materials such as zeolites and activated carbons, metal–organic frameworks(MOFs) are considered as a type of promising materials for gas separation and storage. In this contribution, we review the recent research advance of MOFs in some relevant applications, including CO_2 capture, O_2 purification, separation of light hydrocarbons, separation of noble gases, storage of gases(CH_4,H_2, and C_2 H_2) for energy, and removal of some gaseous air pollutants(NH_3, NO_2, and SO_2). Finally, an outlook regarding the challenges of the future research of MOFs in these directions is given.
基金Project(20576142) supposed by the National Natural Science Foundation of China Project(2009DFA31270) supported by the International Cooperation Project of Ministry of Science and Technology of China
文摘A reliable ultrasound-assisted extraction （UAE） method combined with HPLC-UV for quantification of eight active alkaloids in fruits of Macleaya cordata （Willd） R. Br. was developed. The optimization conditions of UAE were obtained by using Box-Behnken design of response surface methodology. Chromatography was carried out using a Kromasil C18 column by gradient elution with 0.1% phosphoric acid aqueous solution for HPLC-UV. All calibration curves showed good linear correlation coefficients （R^2〉0.999 6） and recoveries （from 97.3% to 104.9%） were acceptable. 1,1-diphenyl-2-picrylhydrazyl （DPPH） method was employed to test the antioxidant activity of the extract from the samples. The proposed method was successfully applied to quantifying eight components in nine samples of M.cordata, and significant variations of alkaloid contents and antioxidant aetivity of the samples from different habitats were demonstrated. It presents a powerful proof for the selection of the best sources to extract eight kinds of alkaloids.
文摘The nV‐MCM‐41 catalysts were prepared by one‐step hydrothermal synthesis and applied to the oxidative dehydrogenation of propane（ODHP） in the presence of CO2. Several state‐of‐the‐art char‐acterization methods were performed to explore the correlation between catalytic performance and the physicochemical characterizations of the catalysts. Because moderate amounts of V species were introduced into the framework of MCM‐41, the catalyst maintained a large specific surface area, a highly ordered mesoporous structure, and highly dispersed V active sites（monomeric and dimeric V oxide species）, while the high‐vanadium‐doping catalysts caused an enhancement in the number of acidic sites and V2O5 crystallites. The ODHP reaction showed that the 6.8 V‐MCM‐41（V content 6.8 wt%） catalyst exhibits high activity and stability, and the C3H8/CO2 molar ratio（1：4） was suitable. The promoting effect of CO2 on the oxidative dehydrogenation of ODHP was demonstrated as the reaction coupling mechanism and ＂lattice oxygen＂ mechanism.
