Interface and energy band manipulation of Bi2O3-Bi2S3 electrode enabling advanced magnesium-ion storage

Rechargeable magnesium-ion(Mg-ion)batteries have attracted wide attention for energy storage.However,magnesium anode is still limited by the irreversible Mg plating/stripping procedure.Herein,a well-designed binary Bi_(2)O_(3)-Bi_(2)S_(3)(BO-BS)heterostructure is fulfilled by virtue of the cooperative interface and energy band engineering targeted fast Mg-ion storage.The built-in electronic field resulting from the asymmetrical electron distribution at the interface of electron-rich S center at Bi_(2)S_(3) side and electron-poor O center at Bi_(2)O_(3) side effectively accelerates the electrochemical reaction kinetics in the Mg-ion battery system.Moreover,the as-designed heterogenous interface also benefits to maintaining the electrode integrity.With these advantages,the BO-BS electrode displays a remarkable capacity of 150.36 mAh g^(−1) at 0.67 A g^(-1) and a superior cycling stability.This investigation would offer novel insights into the rational design of functional heterogenous electrode materials targeted the fast reaction kinetics for energy storage systems.

Interface electron collaborative migration of Co–Co3O4/carbon dots:Boosting the hydrolytic dehydrogenation of ammonia borane

Ammonia borane(AB)is an excellent candidate for the chemical storage of hydrogen.However,its practical utilization for hydrogen production is hindered by the need for expensive noble-metal-based catalysts.Herein,we report Co-Co3O4 nanoparticles(NPs)facilely deposited on carbon dots(CDs)as a highly efficient,robust,and noble-metal-free catalyst for the hydrolysis of AB.The incorporation of the multiinterfaces between Co,Co3O4 NPs,and CDs endows this hybrid material with excellent catalytic activity(rB=6816 mLH2 min^-1 gCo^-1)exceeding that of previous non-noble-metal NP systems and even that of some noble-metal NP systems.A further mechanistic study suggests that these interfacial interactions can affect the electronic structures of interfacial atoms and provide abundant adsorption sites for AB and water molecules,resulting in a low energy barrier for the activation of reactive molecules and thus substantial improvement of the catalytic rate.

Enhancing catalytic toluene oxidation over MnO2@Co3O4 by constructing a coupled interface

Herein,a bottom-down design is presented to successfully fabricate ZIF-derived Co3O4,grown in situ on a one-dimensional(1D)α-MnO2 material,denoted as α-MnO2@Co3O4.The synergistic effect derived from the coupled interface constructed betweenα-MnO2 and Co3O4 is responsible for the enhanced catalytic activity.The resultantα-MnO2@Co3O4 catalyst exhibits excellent catalytic activity at a T90%(temperature required to achieve a toluene conversion of 90%)of approximately 229℃,which is 47 and 28℃ lower than those of the pureα-MnO2 nanowire and Co3O4-b obtained via pyrolysis of ZIF-67,respectively.This activity is attributed to the increase in the number of surface-adsorbed oxygen species,which accelerate the oxygen mobility and enhance the redox pairs of Mn^4+/Mn^3+ and Co^2+/Co^3+.Moreover,the result of in situ diffuse reflectance infrared Fourier transform spectroscopy suggests that the gaseous oxygen could be more easily activated to adsorbed oxygen species on the surface of α-MnO2@Co3O4 than on that of α-MnO2.The catalytic reaction route of toluene oxidation over theα-MnO2@Co3O4 catalyst is as follows:toluene→benzoate species→alkanes containing oxygen functional group→CO2 and H2O.In addition,the α-MnO2@Co3O4 catalyst shows excellent stability and good water resistance for toluene oxidation.Furthermore,the preparation method can be extended to other 1D MnO2 materials.A new strategy for the development of high-performance catalysts of practical significance is provided.

Aerophilic Triphase Interface Tuned by Carbon Dots Driving Durable and Flexible Rechargeable Zn‑Air Batteries

Efficient bifunctional catalysts for oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)are vital for rechargeable Zn-air batteries(ZABs).Herein,an oxygen-respirable sponge-like Co@C–O–Cs catalyst with oxygen-rich active sites was designed and constructed for both ORR and OER by a facile carbon dot-assisted strategy.The aerophilic triphase interface of Co@C–O–Cs cathode efficiently boosts oxygen diffusion and transfer.The theoretical calculations and experimental studies revealed that the Co–C–COC active sites can redistribute the local charge density and lower the reaction energy barrier.The Co@C–O–Cs catalyst displays superior bifunctional catalytic activities with a half-wave potential of 0.82 V for ORR and an ultralow overpotential of 294 mV at 10 mA cm^(−2) for OER.Moreover,it can drive the liquid ZABs with high peak power density(106.4 mW cm^(−2)),specific capacity(720.7 mAh g^(−1)),outstanding long-term cycle stability(over 750 cycles at 10 mA cm^(−2)),and exhibits excellent feasibility in flexible all-solid-state ZABs.These findings provide new insights into the rational design of efficient bifunctional oxygen catalysts in rechargeable metal-air batteries.

Study on Interface between Sub-micron Particles and Matrix in Al_2O_3p/Al Composites

The microstructural characteristic of 1070AI matrix composites reinforced by 0.15 祄 AI2O3 particles whose volume fraction was 40% was investigated by TEM and HREM. The results showed that the interface between the matrix and reinforcements was clean and bonded well, without any interfacial reaction products. There were some preferential crystallographic orientation relationships between Al matrix and AI2O3 particle because of the lattice imperfection on the surface of Al2O3 particles.

THE SiO_(2)H_(2)O INTERFACE AND EFFECTS ON QUARTZ ACTIVATION IN FLOTATION SYSTEM

The correlation between surface complexation at the SiO_(2)H_(2)O interface and quartz notation behavior was studied.Computer assisted calculations,using the programs SOLGASWATER,were adapted in order to con-struct distribution diagrams of surface speciation in the SiO_(2)-metal ion-H^(+) system in aqueous solutions.Equilib-rium constants for both surface and solution reactions were introduced in the composition matrix.Surface complexation,surface charge as well as notation results were compared and a good agreement was obtained.Furthermore,flotation mechanisms of quartz activation by common metal ions like Ca^(2+),Mg^(2+),Fe^(2+) are quantitatively discussed based on the surface reaction equilibrium constants.

The Film-forming Behavior on the Interface between Air and Hydrosol of Fe_2O_3 Nanoparticles

The film forming behavior on the interface between air and hydrosol of Fe2O3 nanoparticles was investigated by the surface pressure-time isotherms, the surface pressure-trough area isotherms, Brewster angle microscopy and transmission electron microscopy. It is found that the freshly prepared hydrosol of Fe2O3 nanoparticles is not stable. The surface pressure increases with the aging time and finally approaches a constant, and the smaller the concentration is, the smaller the surface pressure is stabilized at and the shorter the time the hydrosol reaching stable needs. The surface pressure also increases with compression until collapsed, and the longer the hydrosol is aged, the higher the collapsing pressure is. A uniform and compact film composed of nanoparticles with an average diameter of about 2-3 nm on the air-hydrosol interface is observed by Brewster angle microscope and transmission electron microscope.

Interface states in Al_2O_3/AlGaN/GaN metal-oxide-semiconductor structure by frequency dependent conductance technique

Frequency dependent conductance measurements are implemented to investigate the interface states in Al2O3/A1GaN/GaN metal-oxide-semiconductor （MOS） structures. Two types of device structures, namely, the recessed gate structure （RGS） and the normal gate structure （NGS）, are studied in the experiment. Interface trap parameters includ-ing trap density Dit, trap time constant ιit, and trap state energy ET in both devices have been determined. Furthermore, the obtained results demonstrate that the gate recess process can induce extra traps with shallower energy levels at the Al2O3/AlGaN interface due to the damage on the surface of the AlGaN barrier layer resulting from reactive ion etching （RIE）.

Research of Trap and Electron Density Distributions in the Interface of Polyimide/Al2O3 Nanocomposite Films Based on IDC and SAXS

The distributions of traps and electron density in the interfaces between polyimide （PI） matrix and Al2O3 nanoparticles are researched using the isothermal decay current and the small-angle x-ray scattering （SAXS） tests. According to the electron density distribution for quasi two-phase mixture doped by spherical nanoparticles, the electron densities in the interfaces of PI/Al2O3 nanocomposite films are evaluated. The trap level density and carrier mobility in the interface are studied. The experimental results show that the distribution and the change rate of the electron density in the three layers of interface are different, indicating different trap distributions in the interface layers. There is a maximum trap level density in the second layer, where the maximum trap level density for the nanocomposite film doped by 25 wt% is 1.054 × 10^22 eV·m^-3 at 1.324eV, resulting in the carrier mobility reducing. In addition, both the thickness and the electron density of the nanocomposite film interface increase with the addition of the doped Al2O3 contents. Through the study on the trap level distribution in the interface, it is possible to further analyze the insulation mechanism and to improve the performance of nano-dielectric materials.

THE TRANSFER BEHAVIOUR OF SOME CATIONS AT WATER/NITROBENZENE INTERFACE BY SEMIDIFFERENTIAL CYCLIC VOLTAMMETRY

The transfer of Sr^2+ and Ba^2+ ion,facilitated by 18-crown-6 present in the aqueous phase,and of succinylcholine ion at w/nb interface were investigated by semi-differeniial cyclic voltammetry.A good polarographic curve of succinylcholine ion dissolved in water was obtained in the system of 0.01 mol/l LiCl(w)-0.01mol/l TBATPB(nb).The peak current is directly proportional to the concentration of SC^2+ ion.It can be used for the determination of SC and the detection limit is 1.05×10^-5mol/l,The apparent D^m and D^mb have been estimated.The transfer of Sr^2+ and of Ba^2+ at the interface are facilitated by 18-Crown-6 present in the aqueous phase and the peak current is directly proportional to the concentration of 18-Crown-6 in water.This method can be used for the determination of the complexing agent and for the stability constant of the complex formed in the aqueous phase.All the experimental results are in keeping with the theoretical.

虚拟I/O模块在DCS以太网通信接口模块上的实现

为减少硬件模块的重复开发,在保留原DCS软硬件系统架构不变的基础上,在以太网通信接口模块硬件上虚拟不同的I/O模块。虚拟I/O模块与硬点I/O模块具有一致的输入、输出及参数属性,且组态方式和产物格式一致。同一以太网通信模块上可在不同的虚拟I/O槽位上配置不同的虚拟I/O模块,如Modbus TCP虚拟I/O模块和GOOSE虚拟I/O模块,进而在同一硬件实现不同的通信功能。虚拟I/O模块的使用一方面减少了DCS系统硬件模块的种类,简化备品备件,另一方面也提高了通信扩展的灵活性和便利性。

Formation of NiFe_2O_4/Expanded Graphite Nanocomposites with Superior Lithium Storage Properties

A Ni Fe_2O_4/expanded graphite(Ni Fe_2O_4/EG)nanocomposite was prepared via a simple and inexpensive synthesis method. Its lithium storage properties were studied with the goal of applying it as an anode in a lithium-ion battery. The obtained nanocomposite exhibited a good cycle performance, with a capacity of 601 m Ah g^(-1)at a current of 1 A g^(-1)after 800 cycles. This good performance may beattributed to the enhanced electrical conductivity and layered structure of the EG. Its high mechanical strength could postpone the disintegration of the nanocomposite structure,efficiently accommodate volume changes in the Ni Fe_2O_4-based anodes, and alleviate aggregation of Ni Fe_2O_4 nanoparticles.

THE INTERFACIAL BEHAVIORS OF ALUMINUM MATRIX COMPOSITE IN DIFFERENT WELDING METHODS

Non-interlayer liquid phase diffusion welding (China Patent) and laser welding methods for aluminum matrix composite are mainly described in this paper. In the non-interlayer liquid phase diffusion welding, the key processing parameters affecting the strength of joint is welding temperature. When temperature rises beyond solidus temperature, the bonded line vanishes. The strength of joint reaches the maximum and becomes constant when welding temperature is close to liquid phase temperature. Oxide film in the interface is no longer detected by SEM in the welded joint. With this kind of technique, particle reinforced aluminum matrix composite Al2 O3p/6061Al is welded successfully, and the joint strength is about 80% of the strength of composite (as-casted). In the laser welding, results indicate that because of the huge specific surface area of the reinforcement, the interfacial reaction between the matrix and the reinforcement is restrained intensively at certain laser power and pulsed laser beam. The laser pulse frequency directly affects the reinforcement segregation and the reinforcement distribution in the weld, so that the weldability of the composite could be improved by increasing the laser pulse frequency. The maximum strength of the weld can reach 70% of the strength of the parent.

Manipulating interfacial stability of LiNi0.5Co0.3Mn0.2O2 cathode with sulfide electrolyte by nanosized LLTO coating to achieve high-performance all-solid-state lithium batteries

All-solid-state lithium batteries(ASSLBs) based on sulfide solid-state electrolytes and high voltage layered oxide cathode are regarded as one of the most promising candidates for energy storage systems with high energy density and high safety.However,they usually suffer poor cathode/electrolyte interfacial stability,severely limiting their practical applications.In this work,a core-shell cathode with uniformly nanosized Li0.5La0.5TiO3(LLTO) electrolyte coating on LiNi0.5Co0.3Mn0.2O2(NCM532) is designed to improve the cathode/electrolyte interface stability.Nanosized LLTO coating layer not only significantly boosts interfacial migration of lithium ions,but also efficiently alleviates space-charge layer and inhibits the electrochemical decomposition of electrolyte.As a result,the assembled ASSLBs with high mass loading(9 mg cm-2)LLTO coated NCM532(LLTO@NCM532) cathode exhibit high initial capacity(135 mAh g^(-1)) and excellent cycling performance with high capacity retention(80% after 200 cycles) at 0.1 C and 25℃.This nanosized LLTO coating layer design provides a facile and effective strategy for constructing high performance ASSLBs with superior interfacial stability.

Experimental study on thermal and mechanical properties of tailings-based cemented paste backfill with CaCl_(2)·6H_(2)O/expanded vermiculite shape stabilized phase change materials

CaCl_(2)·6H_(2)O/expanded vermiculite shape stabilized phase change materials(CEV)was prepared by atmospheric impregnation method.Using gold mine tailings as aggregate of cemented paste backfill(CPB)material,the CPB with CEV added was prepared,and the specific heat capacity,thermal conductivity,and uniaxial compressive strength(UCS)of CPB with different cement-tailing ratios and CEV addition ratios were tested,the influence of the above variables on the thermal and mechanical properties of CPB was analyzed.The results show that the maximum encapsulation capacity of expanded vermiculite for CaCl_(2)·6H_(2)O is about 60%,and the melting and solidification enthalpies of CEV can reach 98.87 J/g and 97.56 J/g,respectively.For the CPB without CEV,the specific heat capacity,thermal conductivity,and UCS decrease with the decrease of cement-tailing ratio.For the CPB with CEV added,with the increase of CEV addition ratio,the specific heat capacity increases significantly,and the sensible heat storage capacity and latent heat storage capacity can be increased by at least 10.74%and 218.97%respectively after adding 12%CEV.However,the addition of CEV leads to the increase of pores,and the thermal conductivity and UCS both decrease with the increase of CEV addition.When cement-tailing ratio is 1:8 and 6%,9%,and 12%of CEV are added,the 28-days UCS of CPB is less than 1 MPa.Considering the heat storage capacity and cost price of backfill,the recommended proportion scheme of CPB material presents cement-tailing ratio of 1:6 and 12%CEV,and the most recommended heat storage/release temperature cycle range of CPB with added CEV is from 20 to 40℃.This work can provide theoretical basis for the utilization of heat storage backfill in green mines.

基于Cr-O-C钝化层改变多晶Cu表面能和表层位错的脱模力与脱模精度

Cr-O-C钝化层可以提高精密电铸脱模精度,但Cr-O-C钝化层对基底表面的钝化规律和对表层的影响尚未清楚。利用分子动力学方法,在多晶Cu表面沉积离散的Cr、O和C原子,获得不同比例和数量的Cr-O-C钝化层。计算结果表明,不同比例的Cr、O和C原子均可以大幅降低多晶Cu的表面能;随着原子数量的增加,多晶Cu的表面能呈下降趋势;Cr-O-C钝化层增加了多晶Cu表层的位错密度;新增加的位错以Shockley位错为主;在一定沉积原子数量内,位错密度有极值。在多晶Cu表面电沉积不同密度的Cr、O和C原子,通过接触角测试验证了Cr-O-C钝化层降低多晶Cu表面能的结论。电沉积脱模强度和脱模表面粗糙度结果显示,随着沉积原子数的增加,脱模强度和脱模表面粗糙度均降低。研究结果可为利用离散Cr-O-C界面辅助精密电铸脱模提供一种解释。

W/O乳化酸体系稳定性实验研究

从多个角度对柴油-盐酸形成的W/O型乳液体系的稳定性进行实验研究,结果表明:当乳化剂的亲油基中引入双键、长度变短、支链结构增多时,乳化酸体系的稳定性会下降;随着酸内相体积分数的增加,乳化酸粘度随之增加,乳化酸的稳定性增强;在高温条件下,密度调节剂会降低乳化酸的稳定性,与玻尔兹曼理论相悖;乳化酸的稳定性还取决于整个体系分散特性,使用脂肪醇增效剂、增加搅拌速度能减小乳液液滴的平均尺寸,增加乳化酸体系的稳定性。

结合隐式元数据和List IO的并行文件系统

并行文件系统中的文件数据与元数据分离管理和分离存储使得系统复杂性上升,可靠性下降,采用将两种数据结合的隐式的元数据管理与存储则可以避免上述问题,而且可以获得元数据的并行服务能力,将Expand隐式元数据管理的简单可靠及元数据并发服务和PVFS高效的ListI/O非连续数据访问的能力相结合,可以同时获得两者的优点。

基于AT89S52的Profibus-DP从站的设计与实现

自2006年Profibus现场总线成为我国现场总线的国家标准(GB/T20540-2006)以来,Profibus-DP从站的开发已逐渐成为当今工业自动化控制及仪表领域的研究热点。针对该热点讨论了采用AT89S52和协议芯片SPC3设计了Profibus-DP从站,分别从Profi-bus-DP从站的硬件设计、软件设计和组网调试三方面展开较详细的讨论,并进行了组网调试。结果表明,该从站能够稳定可靠地运行,有力地促进了Profibus-DP现场总线的推广应用。

高性能CMOS LVDSI/O接口单元的设计研究

提出了一种适用于笔记本电脑平板显示器接口的高性能CMOSLVDSI/O接口单元 ,着重分析了高性能CMOSLVDSI/O接口单元电路结构及其工作原理 ,基于TSMC的 3.3V 0 .2 5 μmCMOSSPICE模型 ,在Cadence的环境下用Spectre仿真器进行模拟 ,仿真结果充分体现了该LVDSI/O接口单元的高速率。