Is platinum-loaded titania the best material for dye-sensitized hydrogen evolution under visible light?

A dye-sensitized photocatalyst combining Pt-loaded TiO_(2) and Ru(Ⅱ)tris-diimine sensitizer(RuP)was constructed and its activity for photochemical hydrogen evolution was compared with that of Pt-intercalated HCa_(2)Nb_(3)O_(10) nanosheets.When the sacrificial donor ethylenediaminetetraacetic acid(EDTA)disodium salt dihydrate was used,RuP/Pt/TiO_(2) showed higher activity than RuP/Pt/HCa_(2)Nb_(3)O_(10).In contrast,when NaI(a reversible electron donor)was used,RuP/Pt/TiO_(2) showed little activity due to back electron transfer to the electron acceptor(I_(3)-),which was gener-ated as the oxidation product of I-.By modification with anionic polymers(sodium poly(styrenesulfonate)or sodium polymethacrylate)that could inhibit the scavenging of conduction band electrons by I_(3)-,the H_(2) production activity from aqueous NaI was improved,but it did not exceed that of RuP/Pt/HCa_(2)Nb_(3)O_(10).Transient absorption measurements showed that the rate of semiconductor-to-dye back electron transfer was slower in the case of TiO_(2) than HCa_(2)Nb_(3)O_(10),but the electron transfer reaction to I3-was much faster.These results indicate that Pt/TiO_(2) is useful for reactions with sacrificial reductants(e.g.,EDTA),where the back electron transfer reaction to the more reducible product can be neglected.However,more careful design of the catalyst will be nec-essary when a reversible electron donor is employed.

柴油—甲醇—水复合乳化燃料的试验研究

本文介绍了一种适合于柴油 -甲醇 -水复合乳化的新型乳化剂的制取方法 ,分析了该种乳化剂的乳化机理 ,探讨了用CR - 2型乳化装置配制柴油 -甲醇 -水复合乳液的工艺 ,并在柴油机台架上进行了试验研究。

用水/燃料乳化系统降低废气排放

一种称为Harrier柴油清洁器(HDC)的新式排放控制装置最近投放世界市场。据HDC AG公司在瑞士Monchaltorf的欧洲办事处的工程师讲,该公司设计的清洁器大大地降低了柴油机的微粒子CO和NOx的排放量。HDC AG)是Harrier公司的一个子公司,Harrier公司的总部在美国科罗拉多州丹佛市。

Rapidly determining fuel pollution level of aviation lubricating oil 50-1-4Φby mid-infrared spectrometry

A series of aviation lubrication oil 50-1-4φ samples were prepared with different RP-3 content, and then these sam- ples were analyzed by Fourier transform mid-infrared spectrometer （FTIR）. The infrared region of 805--755 cm-1 was selected as quantitative area for determining fuel pollution level of aviation lubrication oil. Finally, correlation of the testing peak area and the fuel pollution level of corresponding samples were analyzed, and the regression equation was proposed. The results show that determining jet fuel pollution level of aviation lubricating oil by FTIR is feasible and reliable.

Electricity Generation Using Membrane-less Microbial Fuel Cell during Wastewater Treatment

An upflow mode membrane-less microbial fuel cell （ML-MFC） was designed for wastewater treatment. Granular graphite electrodes, which are flexible in size, were adopted in the ML-MFC. Microbes present in anaerobic activated sludge were used as the biocatalyst and artificial wastewater was tested as substrate. During the electrochemically active microbe enrichment stage, a stable power output of 536 mW.m-3 with reference to the anode volume was generated by the ML-MFC running in batch mode. The voltage output decreased from 203 mV to about 190 mV after the ML-MFC was changed from batch mode to normally continuous mode, indicating that planktonic electrochemically active bacterial strains in the ML-MFC may be carried away along with the effluent. Cyclic voltammograms showed that the attached microbes possessed higher bioelectrochemical activity than the planktonic microbes. Forced aeration to the cathode benefited the electricity generation obviously. Higher feeding rate and longer electrode distance both increased the electricity generation. The coulombic yield was not more than 20% throughout the study, which is lower than that of MFCs with membrane. It is proposed that dissolved oxygen diffused from the cathode to the anode may consume part of the substrate.

Recent advances in one-dimensional nanostructures for energy electrocatalysis

Catalysts play decisive roles in determining the energy conversion efficiencies of energy devices.Up to now,various types of nanostructured materials have been studied as advanced electrocatalysts.This review highlights the application of one‐dimensional(1D)metal electrocatalysts in energy conversion,focusing on two important reaction systems-direct methanol fuel cells and water splitting.In this review,we first give a broad introduction of electrochemical energy conversion.In the second section,we summarize the recent significant advances in the area of 1D metal nanostructured electrocatalysts for the electrochemical reactions involved in fuel cells and water splitting systems,including the oxygen reduction reaction,methanol oxidation reaction,hydrogen evolution reaction,and oxygen evolution reaction.Finally,based on the current studies on 1D nanostructures for energy electrocatalysis,we present a brief outlook on the research trend in 1D nanoelectrocatalysts for the two clean electrochemical energy conversion systems mentioned above.

La_(1-x)Ca_xMn_(1-y)Al_yO_3 perovskites as efficient catalysts for two-step thermochemical water splitting in conjunction with exceptional hydrogen yields

Solar‐driven thermochemical water splitting represents one efficient route to the generation of H2as a clean and renewable fuel.Due to their outstanding catalytic abilities and promising solar fuel production capacities,perovskite‐type redox catalysts have attracted significant attention in this regard.In the present study,the perovskite series La1‐xCaxMn1‐yAlyO3(x,y=0.2,0.4,0.6,or0.8)was fabricated using a modified Pechini method and comprehensively investigated to determine the applicability of these materials to solar H2production via two‐step thermochemical water splitting.The thermochemical redox behaviors of these perovskites were optimized by doping at either the A(Ca)or B(Al)sites over a broad range of substitution values,from0.2to0.8.Through this doping,a highly efficient perovskite(La0.6Ca0.4Mn0.6Al0.4O3)was developed,which yielded a remarkable H2production rate of429μmol/g during two‐step thermochemical H2O splitting,going between1400and1000°C.Moreover,the performance of the optimized perovskite was found to be eight times higher than that of the benchmark catalyst CeO2under the same experimental conditions.Furthermore,these perovskites also showed impressive catalytic stability during two‐step thermochemical cycling tests.These newly developed La1‐xCaxMn1‐yAlyO3redox catalysts appear to have great potential for future practical applications in thermochemical solar fuel production.

Effect of water on extractive desulfurization of fuel oils using ionic liquids： A COSMO-RS and experimental study

When evaluating ionic liquids （ILs） for extractive desulfurization （EDS） of fuel oils, the inevitable presence of water in the system may have a significant and in many cases strongly negative effect. However, few studies have considered this particular issue and a promoted water effect on EDS is scarcely reported. In this work, COSMO-RS was firstly employed to calculate the capacity and selectivity for EDS of various IL/H20 mixtures, which cover different IL characters and a wide water concentration range. Experiments were then conducted with a representative IL [C4MIM]IH2P04], whose stable and even promoted extraction performance with a small amount of water was suggested by COSMO-RS. Through analyses of the desulfurization ratio, the cross- solubility and the water content in the desulfurized fuel, the promoted effect of water within a certain range （〈 10 wt%） was experimentally demonstrated. Moreover, such effect of water was explained combining the viscosity, the solvent-solute interactions and the COSMO-RS based analysis.

Multi-Physics Modeling Assisted Design of Non-Coking Anode for Planar Solid Oxide Fuel Cell Fueled by Low Steam Methane

Internal reformation of low steam methane fuel is highly beneficial for improving the energy efficiency and reducing the system complexity and cost of solid oxide fuel cells(SOFCs).However,anode coking for the Ni-based anode should be prevented before the technology becomes a reality.A multi-physics fully coupled model is employed to simulate the operations of SOFCs fueled by low steam methane.The multi-physics model produces I-V relations that are in excellent agreement with the experimental results.The multi-physics model and the experimental non-coking current density deduced kinetic carbon activity criterion are used to examine the effect of operating parameters and the anode diffusion barrier layer on the propensity of carbon deposition.The interplays among the fuel utilization ratio,current generation,thickness of the barrier layer and the cell operating voltage are revealed.It is demonstrated that a barrier layer of 400μm thickness is an optimal and safe anode design to achieve high power density and non-coking operations.The anode structure design can be very useful for the development of high efficiency and low cost SOFC technology.

Diagnostic of Flooding and Hysteresis Phenomena for Proton Exchange Membrane Fuel Cell using Cyclo-Voltammogram Simulation

Porous electrodes with three-phase reaction in low temperature fuel cells have attracted much attention by their flooding phenomena. In order to have a better understanding of the flooding phenomena inside electrode, it is important to evaluate various discharge conditions of the flooded electrodes. A model of flooded porous electrode under the influence of potential sweep was developed to evaluate the flooding conditions in-situ. The hysteresis of current density vs. time was observed at high sweep rates （1 O0 mV.sl）. It was not observed at low sweep rate （0.1 mV-s~）. In this study, these characteristics of flooding and hysteresis conditions were found to be markedly dependent on the potential scan rate. These dynamic behaviors are interpreted in terms of water saturation response, velocity of water movement, and evaporation rate of water.

Dual Pressure versus Hybrid Recuperation in an Integrated Solid Oxide Fuel Cell Cycle--Steam Cycle

A SOFC （solid oxide fuel cell） cycle running on natural gas was integrated with a ST （steam turbine） cycle. The fuel is desulfurized and pre-reformed before entering the SOFC. A burner was used to combust the remaining fuel after the SOFC stacks. The off-gases from the burner were used to produce steam in a HRSG （heat recovery steam generator）. The bottoming steam cycle was modeled with two configurations： （1） a simple single pressure level and （2） a dual pressure level with both a reheat and a pre-heater. The SOFC stacks in the present SOFC-ST hybrid cycles were not pressurized. The dual pressure configuration steam cycle combined with SOFC cycle （SOFC-ST） was new and has not been studied previously. In each of the configuration, a hybrid recuperator was used to recovery the remaining energy of the off-gases after the HRSG. Thus, four different plants system setups were compared to each other to reveal the most superior concept with respect to plant efficiency and power. It was found that in order to increase the plant efficiency considerably, it was enough to use a single pressure with a hybrid recuperator instead of a dual pressure Rankine cycle.

An analysis of an ethanol-based, whole-crop refinery system in China

Bio-fuel can be used to help transition from a petroleum-based society to a bio-based society. Ever since the China Development and Reform Commission suspended the approval of crop processing programs, second-generation bio-ethanol research and industrialization processes have attracted significant attention. In 2020, bio-ethanol production is predicted to reach 10 million tons. Currently, there are a few domestic enterprises that have established different scaled pilot or demonstration bases for cellulosic ethanol, which reduce the cost of ethanol by continuously improving pretreatment and hydrolysis techniques. In the next three years, these enterprises will realize large-scale commercial production. Given the practical problems in cellulosic ethanol plant construction and operation(e.g., marketing price variation and difficulties in feedstock collection), this paper began with the concept of a "whole-crop refinery" and presented a solution to the integration of industry and agriculture as well as multi-crop refining. This paper then took the whole-crop refining system of corn as an example and presented an analysis of the logistics, energy flow, and economical efficiency of the system. The results demonstrated that the integrated system could properly reduce the required fixed investments in production equipment,shared utilities, and wastewater treatment facilities, as well as reduction of energy consumption. Although the proposed system has several problems, it brings the long-term goal of large-scale commercial application closer than ever.

Torrefied Pellets as Fuel for Two-Stage Technology of Biomass Conversion into Synthesis Gas

One of the most important properties of the torrefied pellets, along with high calorific value, is their hydrophobicity. Inability to absorb moisture and self-destruct under its influence determine possibility of using of pellets in the pyrolysis reactor. For the technology of two-stage thermal processing of biomass, developed at the Joint Institute for High Temperatures, the amount of synthesis gas which can be obtained from one kilogram of torrefied pellets is also important. A construction of the pilot torrefaction reactor powered by flue gas is shown. The results of experimental investigations of hydrophobicity of torrefied pellets produced by the reactor and quantity of synthesis gas which can be obtained by two-stage thermal processing of the pellets are presented. It is shown that torrefaction allows simplifying the process of conversion of pellets into synthesis gas without significant reduction in the volume of the gas.

Submicron γ-LiAlO_2 Powder Synthesized from Boehmite

The present study reports a simple,effective and energy-efficient method to prepare γ-LiAlO2 powder as a matrix in a molten carbonate fuel cell(MCFC).In our experiments,aqueous solution based sol-gel technique was used to synthesize γ-LiAlO2.Highly dispersed AlOOH·nH2O and LiOH·H2O aqueous solutions were mixed to form a colloid mixture,which was calcined to synthesize γ-LiAlO2.Thermogravimetric analysis(TGA),X-ray dif-fraction(XRD),and scanning electron microscopy(SEM) were used to study the composition and morphology of the intermediate and final products.The analysis results showed that an intermediate product Li2Al4CO3(OH)12 was produced after the colloid mixture was dried at 80 ℃,and highly purified γ-LiAlO2 powder with fine particle size was resulted from the subsequent calcinations.A single MCFC was assembled with a matrix of the γ-LiAlO2 pow-der.The testing results showed that the matrix performed well in preventing gas leakage.

Dynamics of Lumber Production from Buttressed-Stumps of Logging Residues Using a Fuel Powered Horizontal Mobile Bandsaw Machine

Logging residue can be defined as any form of wood, which under the highest stage of technological development could be used in manufacturing but is left in the forest during logging. Lumber production from logging residues of a previous logging activity by a timber firm was undertaken with the objective of determining the suitability of utilizing buttressed-stumps as raw material for the timber industry. A horizontal mobile bandsaw machine was used to process the buttressed-stumps into lumber. The machine was characterized by a thin-kerr sawing technology （kerf-width 1.6 mm） compared to the conventional bandsaw machines of kerr-widths ranging from 3.0-4.5 mm. Lumber value and volume yields, fuel consumption rate, frequency of tool replacement and lumber production rate were assessed. Results indicated that there is the potential to increase timber production from logging residues by utilizing buttressed-stumps. Lumber value and volume yields of eight timber species investigated in this study ranged from 5%-31% and 34%-54% respectively. Fuel consumption rate which increased with increasing wood density, ranged from 5-14.5 liters/m3 of lumber produced. Frequency of saw replacement increased with increasing wood density. The number of saws required to produce one cubic meter of lumber, ranged from 1 to 7. Lumber production rate ranged from 0.10-0.38 m3/hour, increasing with decreasing wood density.

Research on Advantage and New Use of Korshinsk Peashrub Resources

Korshinsk Peashrub, a kind of excellent shrub resources in our country, is widely distributed in＂Three North＂ areas, namely, northeast, northwest and north China. The adaptability and survival rate of Korshinsk Peashrub are quite high and it has a strong resistance to coldness, drought and barren lands. The ability of branching and regeneration is considerably high, and its branches need to be chopped every four to five years, so the period of chopping for Korshinsk Peashrub is short, and the yield is high. Therefore, the advantages of Korshinsk Peashrub, such as abundant resources, easy to obtain, and high yield, should be made full use of, and the branches during chopping period should be fully utilized. Research on Korshinsk Peashrub resources can not only promote new development of the theory that applies to the specific biomass of Korshinsk Peashrub, but also help re- alizing environment friendly and convenient to use. It has great practical significance. The paper mainly introduces the advantages and research status of Korshinsk Peashrub resources in China. On this topic, new use of Korshinsk Peashrub should be explored, so as to make full use of Korshinsk Peashrub resources, and improve their application value further more.

Electricity generation during wastewater treatment by a microbial fuel cell coupled with constructed wetland

A membrane-less constructed wetland microbial fuel cell （CW-MFC） is constructed and operated under continuous flow with a hydraulic retention time （HRT） of 2 d. Fed with glucose, the CW-MFC generates a stable current density of over 2 A/m3 with a resistor of 1 kΩ and has a chemical oxygen demand （COD） removal efficiency of more than 90% after the startup of 2 to 3 d. A series of systems with the electrode spacings of 10, 20, 30 and 40 cm are compared. It is found that the container with the electrode spacing of 20 cm gains the highest voltage of 560 mV, the highest power density of 0. 149 W/m 3, and the highest Coulombic efficiency of 0.313%. It also has the highest COD removal efficiency of 94. 9%. In addition, the dissolved oxygen （DO） concentrations are observed as the lowest level in the middle of all the CW-MFC reactors. The results show that the more COD is removed, the greater power is generated, and the relatively higher Coulombic efficiency will be achieved. The present study indicates that the CW-MFC process can be used as a cost-effective and environmentally friendly wastewater treatment with simultaneous power generation.

Visible‐light‐driven nonsacrificial hydrogen evolution by modified carbon nitride photocatalysts

Pt‐loaded graphitic carbon nitride(g‐C_(3)N_(4))is known to be a good photocatalyst for H_(2) evolution under visible light.In most cases,however,sacrificial electron donors such as triethanolamine are required for the water‐splitting operation,and nonsacrificial H_(2) evolution by g‐C_(3)N_(4) remains a challenge.In this work,we investigated the photocatalytic activities of carbon nitride nanosheet(NS‐C_(3)N_(4)),which was prepared by thermal treatment of urea,for nonsacrificial H_(2) evolution using reversible electron donors under visible light(λ>400 nm).Whereas Pt‐loaded NS‐C_(3)N_(4) did not produce H_(2) from aqueous solutions containing I−,Fe^(2+),or[Fe(CN)_(6)]^(4−),modification of the Pt/NS‐C_(3)N_(4) photocatalyst with CrO_(x) led to observable H_(2) evolution.Transmission electron microscopy observations and energy‐dispersive X‐ray spectroscopic analysis suggested that a Pt‐core/CrO_(x)‐shell structure was formed on the NS‐C_(3)N_(4).The CrO_(x)/Pt/NS‐C_(3)N_(4) served as a H_(2)‐evolution photocatalyst for visible‐light‐driven Z‐scheme overall water splitting,in combination with a modified WO_(3) photocatalyst,in the presence of a[Fe(CN)_(6)]^(3−/4−)redox mediator.

Determination of Hydrogen Production from Rich Filtration Combustion with Detailed Kinetics Based CFD Method

Computational fluid dynamics （CFD） combined with detailed chemical kinetics was employed to model the filtration combustion of a mixture of methane/air in a packed bed of uniform 3 mm diameter alumina spherical particles. The standard k-ε turbulence model and a methane oxidation mechanism with 23 species and 39 elemental reactions were used. Various equivalence ratios （1.47, 1.88, 2.12 and 2.35） were studied. The numerical results showed good agreement with the experimental data. For ultra-rich mixtures, the combustion temperature exceeds the adiabatic value by hundreds of centigrade degrees. Syngas （hydrogen and carbon monoxide） can be obtained up to a mole fraction of 23%. The numerical results also showed that the combination of CFD with detailed chemical kinetics gives good performance for modeling the pseudo-homogeneous flames of methane in porous media.

A Study on Conversion of Marine Diesel Engines Using Blended Palm Oil for Inland Waterway Vessels in Vietnam

The climate change and limitation of natural resources becomes main obstacle for the global economical development. So, the Vietnamese Government is very much concerned with reduction of harmful gas discharging from the inland-water way ships. To overcome the problems, there are many counter-measures proposed such as： renovation of machinery and equipment, using re-creative energy and so on. The author＇s idea is to find a suitable method which can be applied on board of the inland-water ships to reduce discharging toxic gas by using blended palm oil as alternative fuel for marine diesel engines. Due to some disadvantages of the bended palm oil in comparison with traditional DO （diesel oil）, such as： low freezing point, high viscosity, low stability of blended fue, therefore somehow, the blended palm oil must be made a ship directly on board. With this idea, the author has designed and made agitate mixing equipment working on-line with fuel supply system of a diesel engine. The mixing equipment, then, has been tested at shore-side laboratory as well as on board ships. The research results showed that the fuel mixture （palm oil-DO） made by this mixing equipment is fully usable to replace traditional DO for marine diesel engines installed on board ships of inland water way in Vietnam. The Vietnamese Government accepted the research results as prerequisite to devise specific and practical action plans to reduce the pollution from the inland water way ships in coming years.