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Corrosion Resistance of Valve Steels in combustion Gases from Gasoline and Propane-Butane

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Journal of Mechanics engineering and Automation 2013年第10期3卷 656-659页

作者： Zbigniew Jurasz Krzysztof Adamaszek Materials Testing Department BOSMAL Automotive Research & Development Institute Ltd. Bielsko-Biala 43-300 Poland

The corrosion resistances of widely used X33CrNiMnN23-8, X50CrMnNiNbN21-9, X53CrMnNiN20-8 and X55CrMnNiN20-8 high-alloyed austenite valves steels in combustion engines have been compared. The comparison was performed on the basis of results of kinetic corrosion of the test steels in combustion gases from gasoline with 5% ethanol additive （v/v） and the combustion gases from propane-butane. The corrosion test was performed gravimetrically under thermal shock conditions by heating samples of the test steels from room temperature up to 1,173 K in exhaust gases from a combustion engine, and holding them at this temperature for 2 h and then cooling at room temperature for about 25 min. Then the same thermal shock was repeated and after every 10 to 20 such cycles the mass of the specimens was measured. This experiment simulated the working conditions of a highly thermal loaded exhaust valve in a spark ignited engine. The analysis performed shows that the corrosion resistances of X33CrNiMnN23-8 and X50CrMnNiNbN21-9 valve steels in an environment of combustion gases from propane-butane and in gases from gasoline with 5% ethanol additive （v/v） are comparable, whereas the corrosion resistance of X53CrMnNiN20-8 and X55CrMnNiN20-8 valve steels in an environment of combustion gases from propane-butane is slightly worse than in gases from gasoline with 5% ethanol additive （v/v）.

关键词： Valve steels combustion gases corrosion resistance

Development Tendency Study of Hybrid Electric Vehicle Transmission Considering an Optimized Energy Management Strategy

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Development Tendency Study of Hybrid Electric Vehicle Transm...

2018中国汽车工程学会年会

作者： SHI Tianze ZHAO Fuquan HAO Han LIU Zongwei Tsinghua Automotive Strategy Research institute State Keylaboratory of Automotive Safety and EnergyTsinghua University

Energy conservation and emission reduction have become increasingly significant for automobiles due to the severity of the current energy situation and Hybrid Electric Vehicle（HEV） technology is one of the most promising *** this paper,the total efficiency of HEV powertrain is *** improve the total efficiency,the engine should be regulated to work in high efficiency area,and drive the wheel *** on this,a Direct Drive Area（DDA） energy management strategy is *** typical HEV models are built to compare the fuel consumption using DDA and rule based ***,the function of transmission system in HEV considering DDA is *** transmission in HEV should regulate the engine to work in high efficiency area as much as possible,which is rather different with those in internal combustion engine *** functional change may lead transmission systems to have less gears with optimal *** this conjecture is verified,the manufacturing cost of HEV could be largely reduced.

关键词： HEV transmission energy management engine

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缸内直喷射流点火汽油机的燃烧优化

汽车工程 2021年第11期43卷 1631-1637,1644页

作者：赵自庆齐运亮田宁张翼刘聪姚毅王志清华大学车辆与运载学院北京100084 California institute of Technology PasadenaCA 91125USA 东风汽车技术中心武汉430058

射流点火有助于实现稀燃,提升发动机热效率。本文中在一台多缸汽油机上安装了射流点火器,开展了基于喷射策略的射流点火燃烧优化。首先,在原机以普通火花点火运行的高效范围内确定了最低油耗工况点;然后,基于选定的工况,对比研究了单次... 详细信息

射流点火有助于实现稀燃,提升发动机热效率。本文中在一台多缸汽油机上安装了射流点火器,开展了基于喷射策略的射流点火燃烧优化。首先,在原机以普通火花点火运行的高效范围内确定了最低油耗工况点;然后,基于选定的工况,对比研究了单次喷射和两次喷射策略对射流点火的油耗影响,优化了两次喷射的关键参数;最后,进一步对比了采用不同喷射策略、不同点火方式的发动机燃烧及排放特性。结果表明:相比于火花点火,射流点火可以使原机油耗降低,尤其是采用进气冲程两次喷射的策略时,最低油耗率较原机在相同工况下降低4 g·(kW·h)^(-1);射流点火与火花点火的CO和THC排放基本相当,但NOx排放上升;相较单次喷射策略,使用两次喷射策略可降低NOx排放。

关键词：射流点火两次喷射直喷汽油机

Influence of an oxygenated additive on emission of an engine fueled with neat biodiesel

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Petroleum Science 2017年第4期14卷 791-797页

作者： Amith Kishore Pandian Dinesh Babu Munuswamy Santhanakrishnan Radhakrishana Ramesh Bapu Bathey Ramakrishnan Beemkumar Nagappan Yuvarajan Devarajans Department of Mechanical engineering Sathyabama UniversityChennaiIndia Department of Mechanical engineering Panimalar Engineering CollegeChennaiIndia Department of Mechanical engineering SRM UniversityKattankulathurChennaiIndia Department of Mechanical engineering Chennai Institute of TechnologyChennaiIndia Department of Mechanical engineering Vel Tech Dr.RR&Dr.SR UniversityChennaiIndia

Biodiesel obtained from mustard seed is found to be a promising alternative for petroleum diesel fuel owing to its similarity in physical and chemical properties. In this work, TiO2nano-fluid which acts as an oxygen buffer during combustion was added to mustard oil biodiesel(MOBD) to study its effect on emission characteristics of MOBD. TiO2nano-fluid can provide high surface energy during the course of combustion and reduces the limitations of neat biodiesel. A four-stroke, multi-cylinder,water-cooled, diesel engine was used in the experiments and was fueled with diesel, neat MOBD and MOBD with TiO2nanoparticles at 100 ppm(MOBDT100), 200 ppm(MOBDT200) and 300 ppm(MOBDT300). Experimental results revealed that the TiO2nanoparticles had positive effect on the emission characteristics of MOBD as it acted as an oxidation buffer. MOBDT300 showed a reduction in HC, CO and smoke emissions as compared to pure *** addition, NOxemissions were also reduced by the catalytic activity of the TiO2nanoparticles which reduce the peak combustion temperature. Therefore, TiO2nano-fluid had a positive effect on reducing the emissions associated with neat biodiesel.

关键词： Emissions Nano-fluid Turbulence

Assessing the readability of online information about jones fracture

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World Journal of Methodology 2023年第5期13卷 439-445页

作者： Khaled Farid Khaled Al-Kharouf Faisal Idrees Khan Greg AJ Robertson Orthopaedic Surgery Portsmouth Hospitals UniversityPortsmouth PO63 LYUnited Kingdom internal Medicine Tunbridge Wells HospitalTunbridge Wells E105NJUnited Kingdom Orthopaedic Surgery Queen Alexandra HospitalPortsmouth PO63LYUnited Kingdom

BACKGROUND Hand in hand with technological advancements,treatment modalities continue to *** the turn of the century,the internet has become the number one source of information for almost every ***,many patients look toward the internet as their primary source of information to learn about their respective medical *** American Medical Association and National institute of Health strongly recommend that online medical information be written at the 6th to 8th-grade level to aid comprehension by patients of all literacy *** To assess the readability of online information regarding Jones *** hypothesis is that the reading level of medical information published on websites far exceeds the recommended reading level of 6th-8th grade as proposed by the American Medical Associate and National institute of *** result of this study can help us formulate improved recommendations for publishing more comprehensible material and,thus,eventually improve patient compliance and clinical *** The exact phrase“Jones fracture”was queried on the three most common search engines,Google,Yahoo!,and Bing,on December 28,*** of December 2022,Google held 84%,Bing held 9%,and Yahoo!held 2%of the worldwide search engine market *** pages uniform resource locator from the first three pages of search results were recorded from each search *** web pages were classified according to academic,physician-sponsored,governmental and non-government organizations(NGO),commercial,and unspecified as per formally defined *** associated with an educational institution or medical organization were classified as *** with products for sale,corporate sponsorship,or advertisements were classified as *** websites or NGOs comprised those that received government subsidies or *** that were independently owned by physicians or physician groups were respectively classed as physi

关键词： Jones fracture Jones fracture treatment Jones fracture management Jones fracture prevention Jones fracture types Jones fracture location

A Review and Comparison on Recent Optimization Methodologies for Diesel engines and Diesel Power Generators

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Journal of Power and Energy engineering 2019年第6期7卷 31-56页

作者： Mohamad Issa Hussein Ibrahim Richard Lepage Adrian Ilinca Laboratory of Wind Energy Research Université du Québec à Rimouski Rimouski Canada Technological institute of Industrial Maintenance Sept-Iles Canada

The electrical instability that frequently distinguishes the isolated networks and depends on diesel generators to supply their energy requirements leads to an operation of the diesel generator in a transient dynamic condition and/or at low loads. In addition, extended operation of the diesel generator at partial load develops the condensation of combustion residues on the engine cylinder walls, which, after a certain time, increases friction, reduces the efficiency of the equipment and increases its fuel consumption. On the other hand, recent regulatory changes have led to ever more stringent and evolving emission standards. Among these, the International Maritime Organization (IMO) and the Environmental Protection Agency (EPA) have implemented emission standards in order to reduce exhaust gas emitted by marine diesel engines. To phase lower emission engines as soon as possible, a Tier system was adopted. This paper presents a literature review of existing technologies available to optimize the energy performance of diesel engines and diesel generators in order to reduce the cost of electricity, to increase the diesel engine efficiency and to decrease their fuel consumption and greenhouse gases (GHG) emissions. The proposed optimization methodologies are based on the application of Pre-treatment, internal treatment and Post-treatment technologies for diesel engines and on the application of mechanical and electrical technologies for diesel power generators (DPGs). The list of references given at the end of the paper should offer aids for students and researchers working in this field.

关键词： Diesel engine Diesel Generator Greenhouse Gas Tier System Energy Efficiency MARPOL Annex VI Isolated Communities Off-Grid

Spatial and Temporal Variability of PM2.5 Chemical Compositions and Characteristics of Pollution Episodes in Guanzhong Plain

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Spatial and Temporal Variability of PM2.5 Chemical Compositi...

Comparative Study of Exhaust Emissions from Diesel and Syngas Powered 3.5 kW Compression Ignition engine with and without Load

第八届全国大气细及超细粒子技术研讨会暨PM_(2.5)源谱交流会

作者： Xinyi Niu Junji Cao Zhenxing Shen Hongmei Xu Ting Zhang Rong Zhang School of Human Settlements and Civil engineering Xi'an Jiaotong University Key Lab of Aerosol Chemistry & Physics Institute of Earth Environment Chinese Academy of Sciences institute of Global Environmental Change Xi'an Jiaotong University Department of Environmental Science and engineering Xi'an Jiaotong University

Particulate matter pollution is a serious environmental problem which influencing air quality,regional and global climates,and humanhealth in *** year of fine aerosol samples(PM) were collected at Guanzhong Plain with six sampling sites in different cities from March2012 to *** 24-h average mass concentration of PM was 134.7μg/m,which was high enough to raise serious concerns over the air quality in Guanzhong *** of the six sites exhibited highest OC and EC values in winter,and EC levels always varied with OC concentrations and the variabilityin OC was *** contributions of secondary species SO,NO and NH in total ions were greatest,and the high concentrations in winter were mainly due to emissions from coalcombustion and biomass *** autumn the haze days were severest in Xi’an city with similar tendency of PMvariations,and it was proved that biomass burning was the main emission source of the regional *** winter pollution episodes,the pollution patterns in Guanzhong Plain are similar which were resulted from strong secondary reactions and coal *** addition,mitigating primary particulate emissions including incomplete combustion of coal andbiomass,engine exhaust,and fugitive dust,reducing the emissionsof secondary aerosol precursors including SO,NO,and NH are both importantfor reducing the environmental,economic and health impacts from PM pollutions.

关键词： Guanzhong Plain PM2.5 Chemical compositions Pollution episode

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Journal of Power and Energy engineering 2024年第8期12卷 30-46页

作者： Benson Kariuki Paul Njogu Joseph Kamau Robert Kinyua Sameer Bachani institute of Energy and Environmental Technology Jomo Kenyatta University of Agriculture & Technology Nairobi Kenya Department of Mechanical and Automotive engineering Technical University of Mombasa Mombasa Kenya

Despite diesel engines being highly efficient, with low fuel consumption and reduced carbon dioxide emissions, they emit relatively high levels of particulate matter and oxides of nitrogen (NOx) due to high exhaust gas temperatures. engine emissions show the quality and completeness of combustion. This paper aims to present the results of a study comparing exhaust emissions from a diesel and syngas powered engine. Syngas was produced from co-firing coal and biomass in a gasifier then cleaned, cooled and applied as an alternative fuel in an engine operated from 0 - 100% load. Exhaust-emissions were monitored at this load conditions. The exhaust-temperature was measured using thermocouples and the emission gases were analyzed using Testo 350. The emissions were lower and decreased as the engine load increased, except for sulphur dioxide and NOx. The study shows that levels of carbon monoxide, were higher in a range of 46.5 - 80.2%, while carbon dioxide was 3.3 - 18% higher compared to those from diesel. Hydrocarbon emissions were 480 and 1250 ppm for diesel and syngas respectively. The study reveals that the engine operates optimally at higher loads since hydrocarbons and oxides of carbon are low due to complete combustion at higher temperatures. Exhaust gas temperature was higher in the syngas fuel and increased as the engine load increased in the range of 455.83 - 480.03˚C which influenced the formation of NOx. NOx from diesel was found to be higher, ranging from 32.5 - 40.5%, compared to those from syngas with an engine load of 75%. The study observed that relative to diesel, the emissions of sulfur dioxide at 50% engine load were lower in a range of 23.7 - 57.1%. Emissions of hydrocarbons depended on the degree of substitution of diesel and engine load. The study therefore shows that, relative to diesel, emissions decreased when syngas was used with upgraded syngas from Prosporis juliflora presenting as the best alternative followed by Hyphanae compressa, and last

关键词： Emissions engine Load Temperature Neat-Diesel Syngas

Electrochemical performance of overlithiated Li1＋xNi0.8Co0.2O2： structural and oxidation state studies

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Frontiers of Materials Science 2015年第2期9卷 199-205页

作者： Roshidah RUSDI Norlida KAMARULZAMAN Kelimah ELONG Hashlina RUSDI Azilah ABD-RAHMAN School of Physics and Materials Faculty of Applied Sciences Universiti Teknologi MARA 40450 Shah Alam Selangor Malaysia Centre for Nanomaterials Research Institute of Science Universiti Teknologi MARA 40450 Shah Alam Selangor Malaysia Centre for Foundation Studies in Science University of Malaya 50603 Kuala Lumpur Malaysia School of Chemistry and Environment Faculty of Applied Sciences Universiti Teknologi MARA 40450 Shah Alam Selangor Malaysia

Pure, layered compounds of overlithiated Li1＋xNi0.8Co0.2O2（x = 0.05 and 0.1） were successfully prepared by a modified combustion method. XRD studies showed that cell parameters of the material decreased with increasing the lithium content. SEM revealed that the morphology of particles changed from rounded polyhedral-like crystallites to sharp-edged polyhedral crystals with more doped lithium. EDX showed that the stoichiometries of Ni and Co agrees with calculated synthesized values. Electrochemical studies revealed the overlithiated samples have improved capacities as well as cycling behavior. The sample with x = 0.05 shows the best performance with a specific capacity of 113.29 mA.h.g-1 and the best capacity retention of 92.2% over 10 cycles. XPS results showed that the binding energy of Li ls is decreased for the Li doped samples with the smallest value for the x = 0.05 sample, implying that Li＋ ions can be extracted more easily from Li1.05Ni0.8Co0.2O2 than the other stoichiometries accounting for the improved performance of the material. Considerations of core level XPS peaks for transition metals reveal the existence in several oxidation states. However, the percentage of the＋3 oxidation state of transition metals for the when x = 0.1 is the highest and the availability for charge transition from the ＋3 to＋4 state of the transition metal during deintercalation is more readily available.

关键词： overlithiation LiNio.8Coo.202 interstitial doped Li1.05Ni0.8Co0.2O2 Li1.1Ni0.8Co0.2O2