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Control of diesel soot and NOx emissions with a particulate trap and EGR

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Journal of Environmental Sciences 2005年第2期17卷 245-248页

作者： liurui-xiang GAOXi-yan YANGDe-sheng XUXiao-guang InstituteofInternalComustionEngine DalianUniversityofTechnologyDalian116024China

The exhaust gas recirculation(EGR), coupled with a high-collection efficiency particulate trap to simultaneously control smoke and NOx emissions from diesel engines were studied. This ceramic trap developed previously provided the soot cleaning efficiency of 99%, the regeneration efficiency reaches 80% and the ratio of success reaches 97%, which make EGR used in diesel possible. At the presence of EGR, opening of the regeneration control valve of the trap was over again optimized to compensate for the decrease of the oxygen concentration in the exhaust gas resulted from EGR. The results indicated the cleaning efficiency and regeneration performance of the trap were maintained at the same level except that the back pressure increased faster. A new EGR system was developed, which is based on a wide range oxygen(UEGO) sensor. Experiments were carried out under steady state conditions while maintaining the engine speed at 1600 r/min, setting the engine loads at 0%, 25%, 50%, 75% and 100% respectively. Throughout each test the EGR rate was kept at nine different settings and data were taken with the gas analyzer and UEGO sensor. Then, the EGR rate and engine load maps, which showed the tendencies of NOx, CO and HC emissions from diesel engine, were made using the measured data. Using the maps, the author set up the EGR regulation, the relationship between the optimal amounts of EGR flow and the equivalence ratio,σ, where σ=14.5/AFR.

关键词： particulate trap EGR NOx soot UEGO

Design and Implementation of Hierarchy Cache Using Pagefile

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Wuhan University Journal of Natural Sciences 2004年第6期9卷 890-894页

作者： XIEChang-sheng liurui-fang TANZhi-hu CollegeofComputerScienceandTechnology HuazhongUniversityofScienceandTechnologyWuhan430074HubeiChina

This paper presents a novel hierarchy cache architecture for the purpose of optimizing IO performance. The main idea of the hierarchy cache is to use a few megabytes of RAM and a pagefile to form a two-level cache architecture, The pagefile is equivalent to the cache disk in DCD (Disk Caching Disk). The pagefile outperforms data disks, because data are accessed in different units and different ways. Small writes are collected in the RAM cache first, and data will be transferred to the pagefile in large writes later. When the system is idle, it will destage data from the pagefile to data disks. The performance test results show that the hierarchy cache can improve IO performance dramatically for small writes, and the mail server using the hierarchy cache driver can handle transactions about 2.2 times faster than the normal mail server. The hierarchy cache is implemented as a filter driver, so it's transparent to the current Windows 2000/ Windows XP operating system. Key words hierarchy cache - pagefile - small write - disk caching disk - filter driver CLC number TP 311 Foundation item: Supported by the National Natural Science Foundation of China (60273073)Biography: XIE chang-sheng (1945-), male Professor, research direction: storage system, network storage.

关键词： hierarchy cache pagefile small write disk caching disk filter driver

Properties of radicals created by γ-ray irradiation of silk fabrics

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Nuclear Science and Techniques 2002年第2期13卷 110-114页

作者： liurui－Qin XIELei－Dong 等 ShanghaiInstituteofNuclearResearch TheChineseAcademyofSciencesShanghai201800

The propoerties of radicals fromγ-ray irradiated silk fabrics were studied by electron spin resonance method(ESR).The ESR spectra of silk fabrics irradiated in N2 showed a doublet at room temperature,The doublet became a singlet at g=2.0057 after placing the sample in air for 24 *** can be explained by formation of peroxide *** radical concentration of the irradiated silk fabric and the decay rate of radicals are significantly affected by irradiation *** include the absorbed ***,and water content of the silk fabric ***,no dose rate effect on the radical concentration was *** results are of help in our practice of property modification of silk products by radiation graft copolymerization.

关键词：天然丝 γ射线辐照基特性

Experimental and Simulated Study on the Cylinder Deactivation of Vehicle Gasoline Engine 1

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Repair of left ventricular aneurysm during off-pump coronary artery bypass surgery

2016中国汽车工程学会年会暨展览会

作者： Yu Shuhai Ma Xingxing Ma Zhigang liurui Song Dongxian Technical Center Great Wall Motor Co.Ltd. Hebei Automobile Engineering Technology & Research Center

ISBN: (数字)9789811035272

ISBN: (纸本)9789811035265;9789811098963

Cylinder deactivation performance in vehicle gasoline engine is investigated by experimental and simulated methods,this technology is implemented by adjusting the valve system,and furthermore,a simulated model is built in GT- *** results show that,in cylinder deactivation mode,the overlap degree of naturally aspirated and effective region is highly,it can be considered that the cylinder deactivation engine just operates in naturally aspirated *** 2bar@2000rpm,BSFC of cylinder deactivation is 312.7g/kW · h,the fuel efficiency is improved 12.6% than normal *** the reduced engine speed,fuel effieiceny becomes better,however,with the increment speed,engine NVH characteristic has been deteriorated.

关键词： cylinder deactivation gasoline engine fuel efficiency torsional fluctuation simulated study

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Chinese Medical Journal 2005年第13期118卷 1072-1075页

作者： YUYang GUCheng-xiong WEIHua liurui CHENChang-cheng FANGYing DepartmentofCardiacSurgery BeijingAnzhenHospitalCapitalUniversityofMedicalScienceBeijing100029China

Background Acute myocardial infarction can result in left ventricularaneurysm, which may in turn cause congestive heart failure, ventricular arrhythmia andthromboembolic events. This study evaluates results achieved with a modified linear closure of leftventricular aneurysms during off-pump coronary artery bypass surgery. Methods From January 2001 toMay 2004, 75 patients were operated on for nonruptured, postinfarctional, left ventricular aneurysmduring off-pump coronary artery bypass surgery. Repair was completed on the beating heart tominimize ischaemia and allow assessment of wall function and viability to guide closure. Allpatients presented with symptoms of angina and congestive heart failure or ventricular *** majority (75% ) of the patients were in NYHA functional class Ⅲ or Ⅳ. Preoperative ejectionfraction was 26% ±9%. The mean left ventricular, end diastolic diameter was (57. 5 ±7. 1) mm. Theventricular preoperative and postoperative performances were compared. χ~2 test and Student' s ttest were used to analyse the outcomes. A P value less than 0. 05 was considered *** Hospital mortality was 1. 3% (1/75). Coronary artery bypass was performed with an average of(3. 3 ±1.2) grafts per patient. At the time of followup, all the patients had no symptoms. Themean NYHA class and ejection fraction increased significantly (P < 0.001 ) . The mean leftventricular, end diastolic diameter decreased significantly (P <0. 001). Conclusions Surgicalclosure of left ventricular aneurysm can be performed during off-pump coronary artery bypass. Theoperation is associated with a low inhospital mortality and morbidity. A postoperative improvementin the early term cardiac functions and symptoms and quality of life was documented, increasing ourexpectations of an increased long-term survival.

关键词： heart aneurysm linear closure coronary artery bypass off-pump

Microcrystallin eStructure and Luminescence of ZnS Thin Films

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Semiconductor Photonics and Technology 2000年第1期6卷 20-22页

作者： WANGYu－jiang liurui－tang DepartmentofPhysics XiamenUniversityXiamen361005CHN DepartmentofPhysics XiamenUniversityXiamen3610

The electroluminescence thin films doped with erbium, fabricated by thermal evaporation with two boats, are analyzed by X-ray diffraction (XRD). The relationship between electroluminescence brightness and microstructure of the thin films is obtained. The results reveal that the large grain size in high index plane of deposited microcrystalline film has an effect on electroluminescence characteristics of the film devices.

关键词： Electroluminescence Thin film Microstructure

鄂尔多斯盆地黄陵地区长6致密砂岩储层特征及控制因素分析

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鄂尔多斯盆地黄陵地区长6致密砂岩储层特征及控制因素分析

作者：刘蕊成都理工大学

学位级别：硕士

黄陵地区位于鄂尔多斯盆地南部,紧邻渭北隆起,油气资源丰富,是多年来的勘探热点。研究区长6油层组具有致密储层的特点:物性差、非均质性强、砂体厚度变化较大、油水关系复杂,是石油地质学家多年来研究的目的层位。本文在石油地质学、沉... 详细信息

黄陵地区位于鄂尔多斯盆地南部,紧邻渭北隆起,油气资源丰富,是多年来的勘探热点。研究区长6油层组具有致密储层的特点:物性差、非均质性强、砂体厚度变化较大、油水关系复杂,是石油地质学家多年来研究的目的层位。本文在石油地质学、沉积岩石学、储层地质学等多学科交叉的基础上对鄂尔多斯盆地黄陵地区长6油层组的储层特征及控制因素进行探讨,并结合该层位的地层、沉积相和砂体展布特征对储层进行综合评价,进而完成对优势储层的预测工作。经过上述多学科多角度的研究,得出了以下五点成果及认识:1、在对野外露头剖面观察的基础上,进一步进行了岩心观察、铸体薄片观察、钻井剖面的观察及测井资料的分析和解释,确认研究区长6油层组主要发育在以半深湖沉积为背景的重力流沉积环境中,砂质碎屑流、浊流和半深湖泥等为主要发育的沉积微相。2、对黄陵地区长6致密砂岩储层的砂体平面展布图进行分析,得出其在平面上的展布特征,认为砂体的展布方向与沉积微相的展布基本一致,方向大致为北东-南西向,与北东和南西物源方向相符,砂体总体上呈条带状展布,连片性较好,说明沉积相控制了砂体的展布形态,进而决定了储层的构架。3、通过铸体薄片观察、扫描电镜等方式,对收集的岩心数据进行分析,并结合铸体薄片鉴定数据,得出研究区长6储层砂岩以长石岩屑砂岩及岩屑长石砂岩为主;填隙物主要为粘土杂基和碳酸盐胶结物;孔隙类型以粒间孔、长石溶孔和粒间溶孔为主。对压汞数据进行统计分析,认为研究区长6储层有较高的排驱压力、较小的孔隙及喉道半径,并且孔喉的分选性中偏差,孔隙结构不好,则该储层具有低孔、低渗和低产的基本特点。该储层的成岩作用类型主要包括压实作用、胶结作用和溶蚀作用;从岩心物性分析统计数据结果得知,该储层属于低孔隙度致密—近致密储层;通过对研究区长6油层组岩石孔隙结构、孔渗关系进行研究,结合平面特征,认为长6油层组存在较强的非均质性。4、通过对研究区长6储层岩石学特征及物性特征的研究,认为沉积作用和成岩作用共同控制了黄陵地区长6油层组储层的发育,是主要控制因素。沉积相在宏观上控制了储层物性的好坏,决定了储层的构架,该区北东和南西的物源方向决定了砂体的延伸方向。沿物源方向,砂体的连续性及连通性均很好,含油性可观。研究表明,成岩作用中压实作用和胶结作用破坏了储层的孔隙结构,溶蚀作用和绿泥石胶结是建设性成岩作用,增加了储层的孔隙度,使储层具有更好的物性,说明成岩作用决定了储层的质量。该区长6段裂缝发育,裂缝系统的存在使储层具有了更大的储集空间,进而渗透能力增强。5、结合沉积相、砂体厚度、储层物性特征、储层非均质性等研究成果,对长6油层组各油层段进行综合评价,并对优势储层进行预测,认为优势储层主要发育在Ⅰ类优质储层和Ⅱ类较好储层中。

关键词：鄂尔多斯盆地长6油层组储层特征储层控制因素有利区预测

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小型二冲程直喷发动机爆震燃烧特性数值模拟

华中科技大学学报（自然科学版） 2017年第2期45卷 34-39页

作者：贝太学魏民祥刘锐常诚南京航空航天大学能源与动力学院江苏南京210016

为了了解点火参数对小型二冲程直喷发动机爆震燃烧的影响,利用GT-Power和AVL Fire软件对该发动机整机及燃烧室分别建立了仿真模型,选取扭矩、功率等数据验证了模型的正确性,并对发动机在5 000r/min、大负荷工况下的缸内平均压力和温度... 详细信息

为了了解点火参数对小型二冲程直喷发动机爆震燃烧的影响,利用GT-Power和AVL Fire软件对该发动机整机及燃烧室分别建立了仿真模型,选取扭矩、功率等数据验证了模型的正确性,并对发动机在5 000r/min、大负荷工况下的缸内平均压力和温度、放热率、累积放热量以及爆震强度分布等特性进行了研究.结果表明:在点火提前角由15℃A逐渐增加至35℃A的过程中,小型二冲程直喷发动机的扭矩、功率、缸内混合气燃烧放热量、放热率、缸内平均压力和温度的峰值均呈现出逐渐增大的趋势,而且会伴随着爆震强度表征物的浓度增大,二冲程直喷发动机的爆震倾向加强;当异步点火相位由0℃A逐渐增加至5℃A时,二冲程直喷发动机的扭矩、功率呈现出略微减小的趋势,两个火花塞附近由于湍动能增大,加快了火焰传播速度,使得末端混合气低温反应时间变短,爆震强度表征物的浓度逐步减小,二冲程直喷发动机爆震发生的倾向有所减小.

关键词：二冲程发动机缸内直喷数值模拟燃烧爆震点火提前角异步点火相位

智能投顾与最优投资决策——来自地级市层面的经验证据

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湖南大学学报（社会科学版） 2024年第4期38卷 63-74页

作者：邓浏睿谭婕湖南师范大学商学院湖南长沙410081

通过构建智能投顾对投资者的投资决策的影响机制模型,发现智能投顾能有效降低投资者选择投资顾问的财富门槛,提升投资者对投资顾问的需求并增加投资。这也使更多的投资者能够得到投资顾问的服务,从而获得更高的投资回报。实证研究表明,... 详细信息

通过构建智能投顾对投资者的投资决策的影响机制模型,发现智能投顾能有效降低投资者选择投资顾问的财富门槛,提升投资者对投资顾问的需求并增加投资。这也使更多的投资者能够得到投资顾问的服务,从而获得更高的投资回报。实证研究表明,智能投顾的发展能提升投资者对投资顾问的需求,并在投资者的财富水平、金融素养程度和健康状态方面存在显著差异。

关键词：智能投顾投资决策数字金融

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