State-selective charge exchange cross sections in collisions of highly-charged sulfur ions with helium and molecular hydrogen

The state-selective cross section data are useful for understanding and modeling the x-ray emission in celestial observations.In the present work,using the cold target recoil ion momentum spectroscopy,for the first time we investigated the state-selective single electron capture processes for S^(q+)–He and H_(2)(q=11–15)collision systems at an impact energy of q×20 keV and obtained the relative state-selective cross sections.The results indicate that only a few principal quantum states of the projectile energy level are populated in a single electron capture process.In particular,the increase of the projectile charge state leads to the population of the states with higher principal quantum numbers.It is also shown that the experimental averaged n-shell populations are reproduced well by the over-barrier model.The database is openly available in Science Data Bank at 10.57760/sciencedb.j00113.00091.

Study on Catalytic Wet Oxidation of H_2S into Sulfur on Fe/Cu Catalyst

A wet catalytic oxidation at room temperature was investigated with solution containing ferric, ferrous and cupric ions for H2S removal. The experiments were carried out in a two step process, and the results obtained show that the removal efficiency of H2S can always reach 100% in a 300 mm scrubbing column with four sieve plates, and the regeneration of ferric ions in 200 mm bubble column can match the consumed ferric species in absorption. Removal of H2S, production of elemental sulfur and regeneration of ferric, cupric ions can all be accomplished at the same time. No raw material is consumed except O2 in flue gas or air, the process has no secondary pollution and no problem of catalyst degradation and congestion.

ACID RECOVERY FROM WASTE SULFURIC ACID BY DIFFUSION DIALYSIS

In the process of sulfuric acid production from pyrite, there is a lot of waste acid produced in fume washing with dilute acid. Acid recovery from this sort of waste sulfuric acid by diffusion dialysis is studied in the paper. The mass transfer dialysis coefficient of sulfuric acid of the membrane AFX is measured, the effect of the flowrate of the feed and ratio of feed to water is investigated, and the two kinds of membrane (AFX and S203) are compared. The results show that diffusion dialysis process can separate the metal cation from sulfuric acid effectively, but it is difficult to separate non cation impurities as As - and F -. The contrast tests of the two membranes show that the dialysis mass transfer coefficient of the membrane AFX is larger, while capacity of the removing impurities of membrane S203 is somewhat better.

Determination of Some Heavy-metal-ions Using a Sulfur Ion Modified BZ Oscillating System

A highly sensitive method is developed for the determination of trace amounts of some heavy metal ions in aqueous solution based on the classical Belousov-Zhabotinskii （BZ） oscillating chemical system. Introducing of S^2- ion makes the new oscillating system Ce（SO4）2 - KBrO3 - CH2（COOH）2 - Na2S - H2SO4 have to a high sensitivity for some heavy metal ions such as Ag^＋, Pb^2＋, Hg^2＋, Cd^2＋, Cu^2＋and Bi^3＋ with detection limits down to 10^-12 mol·L^- 1

Simultaneous Determination of Halogen Compounds and Sulfur Oxides in Flue Gas by Ion Chromatography

Ion chromatography （IC） is a suitable analytical method for the determination of anions. As analytical methods for the halogen compounds in flue gas, those of bromine compound, fluorine compound, chlorine （Cl2） and hydrogen chloride （HCI） are listed in JIS. However, IC has not been adopted in JIS except for HCI and C12. Because the carbon dioxide in flue gas is absorbed in a 0.1 M sodium hydroxide solution as an absorber, it is interfered with the measurement of F^- and Cl^- ions. This paper describes the development of the pretreatment equipment for the flue gas analysis by IC, and its applications to real flue gas analysis. The F^-, Cl^-, Br^- and SO4^2- in the absorbing solution can be clearly separated by IC using the pretreatment equipment. The halogen compounds and sulfur oxides in flue gas can be simultaneously determined by IC.

Determination of sulfur anions by ion chromatography-postcolumn derivation and UV detection

A novel method for determination of formaldehyde sulfoxylate, sulfite, thiocyanate, and thiosulfate in foodstuffs by ion chromatography separation with postcolumn derivation and UV detection has been developed. All species are separated at Dionex IonPac AG22A and AS22A with mobile phase of a mixture of 4.5 mmol/L sodium carbonate and 0.8 mmol/L sodium bicarbonate at a flow-rate of 1.0 mL/min. The postcolunm derivation solution was 0.24% iodine in 0.2% phosphate acid and the detection wavelength was set at 288 nm. The detection limits （LOD, signal-to-noise ratio of 3） of formaldehyde sulfoxylate, sulfite, thiocyanate, and thiosulfate were 0.004, 0.006, 0.006, and 0.007 mg/L, respectively. Within-day relative standard deviations （RSD, n = 10） of formaldehyde sulfoxylate, sulflte, thiocyanate, and thiosulfate were 3.24%, 3.76%, 2.68%, and 2.07%, respectively. The recoveries of the four anions were in the range of 67.2-116.5%.

Model of Diffusion of Sulfur in Soda-lime-silicate Glass:An Experimental and Comparative Study

The diffusion property of sulfur on the soda-lime-silicate float glass surface was studied by using secondary ion mass spectroscopy（SIMS）.According to the Fick＇s Second Law,two models of diffusion of sulfur on the glass surface were built.When the diffusion of sulfate（S^6＋） is considered uniquely,the concentration-depth profile of sulfur can not be fitted very well,especially on the top surfaces of the air side and tin side of float glass.So the diffusion of sulfide（S^2-） on the profile of sulfur can not be ignored.The concentration-depth profile of sulfur on both sides of glass can be fitted more exactly when both S^6＋ and S^2- are considerd.Based on the above-mentioned fitting results,it is concluded that the diffusion coefficents of S^6＋ and S^2- of tin side are larger than those of the air side.Moreover,the diffusion coefficents are related to the contacted medium.

Effect of Doped Alkali Metal Ions on the SO_(2) Capture Performance of MnO_(2) Desulfurization Materials at Low Temperature

Sulfur dioxide(SO_(2))emissions from diesel exhaust pose a serious threat to the environment and human health.Thus,desulfurization technology and the performance of desulfurization materials must be improved.In this study,MnO_(2) was modified with various alkali metal ions using the impregnation method to enhance its SO_(2) capture performance.The composites were characterized intensively by scanning electron microscopy,energydispersive X-ray spectroscopy,X-ray diffraction spectroscopy,and Brunauer-Emmett-Teller theory.The SO_(2) capture performance of these composites were measured via thermogravimetry,and the effect of doping with alkali metal ions on the SO_(2) capture performance of MnO_(2) was investigated.Results showed that the SO_(2) capture performance of MnO_(2) could be enhanced by doping with alkali metal ions,and the MnO_(2) composite doped with LiOH(2.0 mol/L)had the best SO_(2) capture capacity(124 mgSO_(2)/gMaterial),which was 18%higher than that of pure MnO_(2).Moreover,the type and concentration of alkali metal ions had varying effects on the SO_(2) capture performance of MnO_(2).In our experiment,the SO_(2) capture performance of the MnO_(2) doped with NaOH,LiCl,Na2CO3,K2CO3,and Li2CO3 composites were worse than that of pure MnO_(2).Therefore,the influences of the type and concentration of alkali metal ions to be doped into desulfurization materials must be considered comprehensively.

Sulfur vacancies and heterogeneous interfaces promote high performance sodium storage of bimetallic chalcogenide hollow nanospheres

Transition metal sulfides have high theoretical capacities and are considered as potential anode materials for sodium-ion batteries.However,due to low inherent conductivity and significant volume expansion,the electrochemical performance is greatly limited.In this study,a nickel/manganese sulfide material(Ni_(0.96)S_(x)/MnS_(y)-NC)with adjustable sulfur vacancies and heterogeneous hollow spheres was prepared using a simple method.The introduction of a concentration-adjustable sulfur vacancy enables the generation of a heterogeneous interface between bimetallic sulfide and sulfur vacancies.This interface collectively creates an internal electric field,improving the mobility of electrons and ions,increasing the number of electrochemically active sites,and further optimizing the performance of Na~+storage.The direction of electron flow is confirmed by Density functional theory(DFT)calculations.The hollow nano-spherical material provides a buffer for expansion,facilitating rapid transfer kinetics.Our innovative discovery involves the interaction between the ether-based electrolyte and copper foil,leading to the formation of Cu_9S_5,which grafts the active material and copper current collector,reinforcing mechanical supporting.This results in a new heterostructure of Cu_9S_5 with Ni_(0.96)S_(x)/MnS_(y),contributing to the stabilization of structural integrity for long-cycle performance.Therefore,Ni_(0.96)S_(x)/MnS_(y)-NC exhibits excellent electrochemical properties following our modification route.Regarding stability performance,Ni0_(.96)S_(x)/MnS_(y)-NC demonstrates an average decay rate of 0.00944%after 10,000 cycles at an extremely high current density of 10000 mA g^(-1),A full cell with a high capacity of 304.2 mA h g^(-1)was also successfully assembled by using Na_(3)V_(2)(PO_(4))_(3)/C as the cathode.This study explores a novel strategy for interface/vacancy co-modification in the fabrication of high-performance sodium-ion batteries electrode.

Insights on advanced g‐C_(3)N_(4)in energy storage:Applications,challenges,and future

Graphitic carbon nitride(g‐C_(3)N_(4))is a highly recognized two‐dimensional semiconductor material known for its exceptional chemical and physical stability,environmental friendliness,and pollution‐free advantages.These remarkable properties have sparked extensive research in the field of energy storage.This review paper presents the latest advances in the utilization of g‐C_(3)N_(4)in various energy storage technologies,including lithium‐ion batteries,lithium‐sulfur batteries,sodium‐ion batteries,potassium‐ion batteries,and supercapacitors.One of the key strengths of g‐C_(3)N_(4)lies in its simple preparation process along with the ease of optimizing its material structure.It possesses abundant amino and Lewis basic groups,as well as a high density of nitrogen,enabling efficient charge transfer and electrolyte solution penetration.Moreover,the graphite‐like layered structure and the presence of largeπbonds in g‐C_(3)N_(4)contribute to its versatility in preparing multifunctional materials with different dimensions,element and group doping,and conjugated systems.These characteristics open up possibilities for expanding its application in energy storage devices.This article comprehensively reviews the research progress on g‐C_(3)N_(4)in energy storage and highlights its potential for future applications in this field.By exploring the advantages and unique features of g‐C_(3)N_(4),this paper provides valuable insights into harnessing the full potential of this material for energy storage applications.

Nanostructured energy materials for electrochemical energy conversion and storage: A review

Nanostructured materials have received tremendous interest due to their unique mechanical/electrical properties and overall behavior contributed by the complex synergy of bulk and interfacial properties for efficient and effective energy conversion and storage. The booming development of nanotechnology affords emerging but effective tools in designing advanced energy material. We reviewed the significant progress and dominated nanostructured energy materials in electrochemical energy conversion and storage devices, including lithium ion batteries, lithium-sulfur batteries, lithium-oxygen batteries, lithium metal batteries, and supercapacitors. The use of nanostructured electrocatalyst for effective electrocatalysis in oxygen reduction and oxygen evolution reactions for fuel cells and metal-air batteries was also included. The challenges in the undesirable side reactions between electrolytes and electrode due to high electrode/electrolyte contact area, low volumetric energy density of electrode owing to low tap density, and uniform production of complex energy materials in working devices should be overcome to fully demonstrate the advanced energy nanostructures for electrochemical energy conversion and storage. The energy chemistry at the interfaces of nanostructured electrode/electrolyte is highly expected to guide the rational design and full demonstration of energy materials in a working device. (C) 2016 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. and Science Press. All rights reserved.

Effect of nitriding-sulfurizing composite treatment on the tribological behavior of titanium alloys

A composite layer was prepared on the surface of Ti-6Al-4V alloy by nitriding-sulfurizing composite treatment,and its microstructure and phase structure were examined by scanning electron microscopy（SEM） and X-ray diffraction（XRD）,respectively.The tribological performance was measured to investigate its dependence on the nitriding-sulfurizing composite treatment process.The results indicated that the composite layer was mainly comprised of Ti2N,TiN,and TiS2.It was found that the composite layer exhibited superior tribological properties under dry friction and absolute sliding conditions due to the formation of sulfides with self-lubricating function.

Carbon coated ultrasmall anatase TiO_2 nanocrystal anchored on N,S-RGO as high-performance anode for sodium ion batteries

Anatase TiO_2 has been investigated as one of the most promising anode materials for sodium ion batteries(SIBs)with low cost and high theoretical capacity.Herein,a composite material of TiO_2 /N,S-RGO@C with carbon coated ultrasmall anatase TiO_2 anchored on nitrogen and sulfur co-doped RGO matrix was successfully prepared by a rational designed process.The composite structure exhibited ultrasmall crystal size,rich porous structure,homogeneous heteroatoms doping and thin carbon coating,which synergistically resulted in elevated electron and ion transfer.The anode exhibited high rate capacities with good reversibility under high rate cycling.The carbon coating was investigated to be effective to prevent active material falling and lead to long term cycling performance with a high capacity retention of 181 m Ah g^(à1)after 2000cycles at 2 C.Kinetic studies were carried out and the results revealed that the superior performance of the composite material were derived from the decreased charge transfer resistance and elevated ion diffusion.Results suggested that the TiO_2 /N,S-RGO@C composite is a promising anode material for sodium ion batteries.

Applications of Transition Metal(Fe,Co,Ni)-Based Metal–Organic Frameworks and their Derivatives in Batteries and Supercapacitors

Metal–organic frameworks(MOFs),which are generally considered to be crystalline materials comprising metal centers and organic ligands,have attracted growing attention because of their controllable structures and high porosity.MOFs based on transition metals(Fe,Co,Ni)are highly effi cient electrode materials for electrochemical energy storage.In this review,the characteristics of Fe-MOFs,Co-MOFs,Ni-MOFs,and their derivatives are summarized,and the relationships between the structures and performance are unveiled in depth.Additionally,their applications in lithium–ion batteries,lithium–sulfur batteries,and supercapacitors are discussed.This review sheds light on the development of MOFs and their derivatives to realize excellent electrochemical performance.

The design of Co_(3)S_(4)@MXene heterostructure as sulfur host to promote the electrochemical kinetics for reversible magnesium-sulfur batteries

The rechargeable Mg-S batteries are attractive because of their resource abundances of Mg and S,high volumetric energy density,and less dendrite property of Mg anodes.However,the development is barred by the intrinsic low electronic conductivity of S and the discharge products as well as the lack of understanding the hidden electrochemical kinetics.Here,a Co_(3)S_(4)@MXene heterostructure is proposed as effective sulfur host for reversible Mg-S batteries.XPS results and density functional theory(DFT)calculation confirm that the chemical interaction between the decorated Co_(3)S_(4)nanocrystals host and polysulfide intermediates could well absorb and catalyze the polysulfides conversion,thus improve the electrochemical redox kinetics.Meanwhile,the MXene matrix could promote Mg ion diffusion dynamics greatly.As a result,the developed Mg-S batteries using the Co_(3)S_(4)@MXene-S as the cathode material could demonstrate high sulfur utilization with specific capacity of 1220 mAh g^(-1) and retain a capacity of 528 mAh g^(-1) after 100 cycles,together with a satisfactory rate performance even at 2 C.This work shed light on the advanced cathode design for reversible high energy Mg-S batteries.

Recent advances on flexible electrodes for Na-ion batteries and Li–S batteries

Flexible energy storage devices are essential for emerging flexible electronics. The existing state-of-the-art Li-ion batteries are slowly reaching their limitation in terms of cost and energy density. Hence, flexible Na-ion batteries (SIBs) with abundanee Na resources and Li-S batteries with high energy density become the alternative for the Li-ion batteries in future. This review summarizes the recent advances in the development of flexible electrode materials for SIBs with metallic matrix and carb on aceous matrix such as carb on nano-tubes, carbon nano-fiber, graphene, carbon cloth, carbon fiber cloth, and cotton textiles. Then, the potential prototype flexible full SIBs are discussed. Further, the recent progress in the development of flexible electrode materials for Li-S batteries based on carb on nano-fiber, carb on nano-tubes, graphene, and cotton textiles is reviewed. Moreover, the design strategies of suitable interlayer, separator, electrolyte, and electrodes to prevent the dissolution and shuttle effect of polysulfides in flexible Li-S batteries are provided. Finally some prospective investigation trends towards future research of flexible SIBs and Li-S batteries are also proposed and discussed. The scientific and engineering knowledge gained on flexible SIBs and Li-S batteries provides conceivable development for practical application in near future.

Green Cycle: Sulfate Sorption from Natural Water on Anionic Clay Compound Obtained from Industry Wastewater

In this paper we are describing a green cycle process. The first step was a novel hydrotalcite-like compound (HTLC) synthesized by a co-precipitating method, under standard ambient temperature and pressure, using chemical industry wastewater rich in divalent and trivalent cations, activated by a thermal treatment and finally characterized by scanning electron microscopy (SEM), energy dispersive X-ray fluorescence (EDS) and thermogravimetric analysis (TGA). The second step was a series of batch sorption tests performed with this activated HTLC and untreated underground sulfurous water from the state of Puebla, México. The HTLC calcined at 500°C/3 h exhibited the best sorption ability for ions, demonstrated a decrease of the hardness and sulfate ions to below the regional legal standards for drinking water. Once inactive after being used in water treatment, the sorbed ions were removed by ion exchange in a carbonate-containing solution, resulting in an 80% recycling of the material which upon activation demonstrated a retained capacity for water treatment. This recyclability suggests the exciting possibility of this novel compound as an efficient “green” technology in water treatment processes.

High Density Fluorine Negative-Ion Source Generated by Utilizing Magnetized SF₆

In a magnetized plasma column generated from an electronegative gas, negative-ions accumulate around the plasma column via radial diffusion. In this study, a dc discharge is applied in SF6 gas to produce a plasma column, and the radial density profile of negative-ions is measured by Langmuir probes using the modified Bohm criterion. The gas pressure and discharge current dependences of negative-ion density are also measured. It is found that the negative-ion density of 8.0 × 1017 m-3 is obtained around the plasma column at r = 1.0 cm when SF6 pressure is 0.13 Pa and discharge current is 0.50 A. The negative-ion density has radial gradient, and the electron density is much lower in this region.

Electrochemical process of sulfur in carbon materials from electrode thickness to interlayer

Lots of efforts have been done on different porous carbon materials as cathode for Lithium–sulfur(Li–S)battery. However, seldom researches have been done on the relationship between cathode thickness and electrochemical performance. Our work investigates the relation between electrochemical performance and cathode thickness with typical porous carbon materials. We explain the phenomenon that only a modest cathode thickness can have the most adequate electrochemical reaction trend through the aspect of thermodynamics(chemical potential) so that the best electrochemical performance can be obtained.Besides, interlayer can remit the shuttle effect but hinder the lithium ion diffusion process simultaneously. And we verify the effect of interlayer thickness on the shuttle effect and lithium ion diffusion process.

流动注射法检测枸杞中二氧化硫残留量的方法比较及风险评估

近年来自动化检测设备以及对应方法相继涌现,本研究使用在线蒸馏-流动注射法与国标中酸碱滴定法、离子色谱法对枸杞中二氧化硫残留量进行检测比较。结果表明,三种方法的测定结果并无显著性差异。在线蒸馏-流动注射法RSD在1.5%~2.4%之间,加标回收率在86.1%~92.7%之间,因其具有自动化程度高、检测周期短的优势,更适合大批量样品的快速准确检测。用在线蒸馏-流动注射法对106批次红枸杞中的二氧化硫残留量进行检测分析,并对枸杞中的二氧化硫残留量进行暴露风险评估。结果显示,二氧化硫超标率达21.7%,枸杞中二氧化硫残留尚未对健康构成威胁。