检索结果-南通市图书馆

Real-world fuel consumption of light-duty passenger vehicles using on-board diagnostic (OBD) systems

在线全文

学校读者我要写书评

暂无评论

Frontiers of Environmental Science & Engineering 2020年第2期14卷 207-216页

作者： xuan Zheng Sheng Lu Liuhanzi yang Min yan Guangyi xu Xiaomeng Wu Lixin Fu Ye Wu College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhen 518060China School of Environment State Key Joint Laboratory of Environment Simulation and Pollution ControlTsinghua UniversityBeijing 100084China International Council on Clean Transportation Beijing 100084China Shenzhen Research Academy of Environmental Sciences Shenzhen 518001China State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex Beijing 100084China

An increasing discrepancy between real-world and type-approval fuel consumption for light-duty passenger vehicles(LDPVs)has been reported by several ***,real-world fuel consumption is measured primarily by a portable emission measurement *** on-board diagnostic(OBD)approach,which is flexible and offers high-resolution data collection,is a promising fuel consumption monitoring *** LDPVs were tested with a laboratory dynamometer based on a type-approval cycle,the New European Driving Cycle(NEDC).Fuel consumption was measured by the OBD and constant-volume sampling system(CVS,a regulatory method)to verify the accuracy of the OBD *** results of the OBD method and the regulatory carbon balance method exhibited a strong linear correlation(e.g.,R^2=0.906-0.977).Compared with the carbon balance results,the fuel consumption results using the OBD were 7.1%±4.3%lower on ***,the real-world fuel consumption of six LDPVs was tested in Beijing using the *** results showed that the normalized NEDC real-world fliel consumption of the tested vehicles was 13%±17%higher than the type-approval-based fuel *** the OBD values are lower than the actual fuel consumption,using a carbon balance method may result in a larger discrepancy between real-word and type-approval ftiel *** means of the operating mode binning and micro trip methods,a strong relationship(R^2=0.984)was established between the average speed and relative fuel *** congested roads(average vehicle speed less than 25 km/h),the fuel consumption of LDPVs is highly sensitive to changes in average speed.

关键词： Fuel consumption Light-duty passenger vehicles On-board diagnostic systems

Analysis of Thermal Behavior for Beam Blank Continuous Casting Mold

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2010年第12期17卷 17-22页

作者： xu Hai-lun WEN Guang-hua SUN Wei WANG Kai-zhong yan Bo College of Materials Science and Engineering Chongqing University Chongqing 400044 China Ma'anshan Iron and Steel Co Ltd Ma'anshan 243003 Anhui China College of Resources and Environmental Science Chongqing University Chongqing 400044 China

Finite element models of steady heat conduction for cross section of beam blank mold were developed by using ABAQUS software. The effect of mold grinding thickness, cooling water velocity, diameter of restrietor rods and water channel design on hot face temperature was analyzed in detail. Attention was focused on the peak temperature and temperature uniformity along hot face. The results showed that the peak temperature of existing mold, about 337.2 ℃, is located in the fillet, and two valleys of hot face temperature are found in flange corner and junction of wide face and narrow face, respectively. Decreasing mold thickness, increasing cooling water velocity and increasing diameter of restrictor rods can all reduce peak temperature and improve temperature uniformity along hot race at the expense of lower overall temperature. Redesigning the water channel can decrease peak temperature and thermal gradient of mold without lowering overall temperature of hot face. In particular, the small hole design can improve temperature uniformity across hot face and obtain the best advantage.

关键词： beam blank continuous casting mold thermal behavior temperature distribution

红杂色沉积建造中铀矿化的特殊岩石矿物特征——以库车坳陷新近系吉迪克组铀矿点为例

在线全文

学校读者我要写书评

暂无评论

岩石矿物学杂志 2024年第5期43卷 1268-1280页

作者：郭强肖菁刘念王强强许强武勇严张磊刘梦魁丁桐核工业北京地质研究院北京100029 核工业二一六大队新疆乌鲁木齐830011

近年来,我国北方砂岩型铀矿勘查在中新生代红杂色沉积建造中不断取得找矿突破,但关于红层中的铀成矿作用机制存在较大争议,成为当前研究的热点。库车坳陷新近纪红层中发育大量铀矿化露头信息,开展相关研究有助于分析红杂色层中铀富集机... 详细信息

近年来,我国北方砂岩型铀矿勘查在中新生代红杂色沉积建造中不断取得找矿突破,但关于红层中的铀成矿作用机制存在较大争议,成为当前研究的热点。库车坳陷新近纪红层中发育大量铀矿化露头信息,开展相关研究有助于分析红杂色层中铀富集机理。通过系统的沉积学、岩石学及矿物学研究对吉迪克组红杂色层铀矿化点进行解剖,发现了较为特殊的铀矿化类型:矿化层产于干旱背景下湖相沉积环境,呈薄层透镜状产于大套红色泥岩中,矿化岩性为灰绿色泥灰岩并发育大量红化硅质团块,矿化具有层控特征并与硅质团块密切相关,硅质团块具有红化微晶石英、萤石、铀石、方解石以及少量自然砷、黄铜矿和重晶石共生矿物组合,与华南花岗岩型硅质脉铀矿化极为相似,显示出深部热液成因特征;综合判断该矿化层具有沉积和热液双重作用,是特殊的热水沉积型铀矿化。这类铀矿化的发现为深部热液携带铀进入沉积盆地发生铀成矿作用带来直接有力证据,丰富了陆相盆地沉积型铀成矿理论。

关键词：库车坳陷新近纪吉迪克组红杂色层硅质团块热液铀矿化

高温热暴露对Ti60钛合金高周疲劳性能的影响

在线全文

学校读者我要写书评

暂无评论

材料热处理学报 2024年第7期45卷 69-78页

作者：张少平郭会明赵子博吴晨田伟钟燕徐建伟曾卫东中国航发四川燃气涡轮研究院四川成都610500 中国科学院金属研究所辽宁沈阳110016 西北工业大学材料学院陕西西安710072

研究了高温热暴露对Ti60钛合金室温旋转弯曲高周疲劳性能的影响,通过分析试样的表面特征和内部组织,阐明了疲劳性能变化的原因。结果表明,600℃×100 h热暴露后合金的室温强度升高、塑性下降,室温旋转弯曲高周疲劳强度由470 MPa提升至54... 详细信息

研究了高温热暴露对Ti60钛合金室温旋转弯曲高周疲劳性能的影响,通过分析试样的表面特征和内部组织,阐明了疲劳性能变化的原因。结果表明,600℃×100 h热暴露后合金的室温强度升高、塑性下降,室温旋转弯曲高周疲劳强度由470 MPa提升至543.3 MPa。疲劳性能的变化是由表面特征和内部组织变化共同引起的,热暴露导致试样表面产生由TiO_(2)及Al_(2)O_(3)组成的氧化膜,表面粗糙度增加、质量变差,对疲劳性能产生不利影响;同时,热暴露致使合金中α_(2)相和硅化物的析出数量增加,且尺寸增加,析出相的变化使得合金强度增加,并进一步提升疲劳强度。综合两方面作用,析出相对旋转弯曲高周疲劳强度的提升强于表面粗糙度增加所产生的不利影响,是疲劳性能提高的主要因素。

关键词： Ti60钛合金热暴露高周疲劳性能析出相表面特征

超临界Lennard-Jones流体结构特性分子动力学研究

在线全文

学校读者我要写书评

暂无评论

物理学报 2020年第7期69卷 1-10页

作者：王艳徐进良李文刘欢华北电力大学低品位能源多相流与传热北京市重点实验室北京102206 华北电力大学电站能量传递转化与系统教育部重点实验室北京102206

研究超临界流体在不同压力和温度的结构特征有助于深刻理解并有效利用超临界流体.本文采用分子动力学方法模拟超临界压力、拟临界温度附近流体的结构及密度波动曲线的排列熵,分析状态参数变化的影响.结果表明,定压下,径向分布函数随温... 详细信息

研究超临界流体在不同压力和温度的结构特征有助于深刻理解并有效利用超临界流体.本文采用分子动力学方法模拟超临界压力、拟临界温度附近流体的结构及密度波动曲线的排列熵,分析状态参数变化的影响.结果表明,定压下,径向分布函数随温度升高,第一峰值位置逐渐向右移动,但右移幅度随着压力偏离临界点距离的增大而减弱,近临界压力时,出现峰值最高点的工况和等温压缩系数的极值点位置一致,压力增大,该现象消失.低压力拟临界点时易出现面积大、相对集中且分布稳定的高/低密度区,无明显嵌套现象.静态结构因子存在一定发散行为,发散的最大值和等温压缩系数极值点所处工况符合.低压力时密度时间序列的波动幅度最大,类周期现象较明显.在分子间势能、等温压缩系数和热运动效应的共同作用下,当压力(P)为1.1倍的临界压力(Pc)时,排列熵在0.99倍的拟临界温度(Tpc)达到最小值,P = 1.3Pc和1.5Pc时,最小排列熵与等温压缩系数的最大值工况点保持一致,压力继续增大,各模拟工况密度和排列熵的波动减弱,流体均匀性增强.

关键词：超临界流体分子动力学结构特征排列熵

Lattice Boltzmann model for combustion and detonation

在线全文

学校读者我要写书评

暂无评论

Frontiers of physics 2013年第1期8卷 94-110页

作者： Bo yan Ai-Guo xu Guang-Cai Zhang yang-Jun Ying Hua Li National Key Laboratory of Computational Physics Institute of Applied Physics and Co~putational Mathe'maties P. O. Box 8009-26 Beijing 100088 China

In this paper we present a lattice Boltzmann model for combustion and detonation. In this model the fluid behavior is described by a finite-difference lattice Boltzmann model by Gan et al. [Physica A, 2008, 387: 1721]. The chemical reaction is described by the Lee-Tarver model [Phys. Fluids, 1980, 23: 2362]. The reaction heat is naturally coupled with the flow behavior. Due to the separation of time scales in the chemical and thermodynamic processes, a key technique for a successful simulation is to use the operator-splitting scheme. The new model is verified and validated by well-known benchmark tests. As a specific application of the new model, we studied the simple steady detonation phenomenon. To show the merit of LB model over the traditional ones, we focus on the reaction zone to study the non-equilibrium effects. It is interesting to find that, at the von Neumann peak, the system is nearly in its thermodynamic equilibrium. At the two sides of the von Neumann peak, the system deviates from its equilibrium in opposite directions. In the front of von Neumann peak, due to the strong compression from the reaction product behind the von Neumann peak, the system experiences a sudden deviation from thermodynamic equilibrium. Behind the von Neumann peak, the release of chemical energy results in thermal expansion of the matter within the reaction zone, which drives the system to deviate the thermodynamic equilibrium in the opposite direction. From the deviation from thermodynamic equilibrium, Δ m *, defined in this paper, one can understand more on the macroscopic effects of the system due to the deviation from its thermodynamic equilibrium.

关键词： lattice Boltzmann method Lee-Tarver model viscous detonation deviation from equilibrium

Synthesis of (R)(E)-3,7-Dimethyl-2-octene-1,8-dioic Acid, a Copulation Released Pheromone Component of Azuki Bean Weevil

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chemical Research in Chinese Universities 2002年第4期18卷 397-399页

作者： YU Guang-ao huanG Jin-xia HOU Jun-li Li yan xu Zhang-huang Department of Chemistry Hubei UniversityWuhan 430062P.R.China

Started from 5-hydroxy-2-pentanone, (R)(E)-3,7-dimethyl-2-octene-1,8-dioic acid, callosobruchusic acid, was synthesized via five steps with D-(-)-camphor sultam as the chiral auxiliary. It was of good optical purity a... 详细信息

关键词： Synthesis (R)(E)-3 7-Dimethyl-2-octene-1 8-dioic acid Copulation released pheromone

Enhancing the intrinsic properties of flower-like BiOI by S-doping toward excellent photocatalytic performances

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2022年第23期118卷 190-198页

作者： Jie Xiong Hong-yan Zeng Sheng xu Jin-Feng Peng Fang-Yuan Liu Li-Hui Wang College of Chemical Engineering Xiangtan UniversityXiangtan 411105China School of Mechanical Engineering Xiangtan UniversityXiangtan 411105China

A facile strategy was proposed to fabricate the S-doped flower-like BiOI microspheres(S-BiOI) for boosting the photocatalytic performance of BiOI via engineering the surface oxygen vacancy and exposed {001}crystal *** S-doping generated oxygen vacancies in BiOI lattice structure to create point defects and exposed {001} crystal planes,resulting in a decrease in bandgap and an enhancement in charges separation,which could significantly hasten the photocatalytic *** concentration of CH_(4) N_(2) S was a key factor to promote the Cr(Ⅵ) reduction *** optimized S-BiOI_(1.25) presented a superior Cr(Ⅵ) removal efficiency of 100% for 60 min,which Cr(Ⅵ) reduction rate was 11.3 times higher than the pristine BiOI and still remained 97.5% Cr(Ⅵ) removal after 5 *** calculation confirmed that the bandgap of the S-BiOI was narrowed compared to that of BiOI,but the S-BiOI still remained the intrinsic band structure of the pristine BiOI.

关键词： BiOI Sulfide doping Oxygen vacancy Photocatalyst Optical absorption

河北省石家庄市栾武路坑塘底泥营养物质分布特征及污染评价

在线全文

学校读者我要写书评

暂无评论

河北地质大学学报 2024年第4期47卷 80-88页

作者：孟德佳徐进韩元代克岩徐磊王军强蔡然清华苏州环境创新研究院江苏苏州215000 北京首创生态环保集团股份有限公司北京100044 石家庄首创水汇环境治理有限公司河北石家庄051430

以石家庄栾武路坑塘为研究对象,利用柱状底泥分层采样器采集0~9m坑塘沉积物样品,研究分析总氮(TN)、总磷(TP)、有机质(OM)的空间分布特征,并对沉积物进行污染风险评价,结果表明:沉积物TN含量在1.33~1.91g·kg^(-1),空间分布特征为坑塘南... 详细信息

以石家庄栾武路坑塘为研究对象,利用柱状底泥分层采样器采集0~9m坑塘沉积物样品,研究分析总氮(TN)、总磷(TP)、有机质(OM)的空间分布特征,并对沉积物进行污染风险评价,结果表明:沉积物TN含量在1.33~1.91g·kg^(-1),空间分布特征为坑塘南部>坑塘北部,为Ⅳ级污染程度;总磷含量在202~1190 mg·kg^(-1),空间分布特征为坑塘南部>坑塘北部,总体表现为轻中度污染;沉积物有机质含量在2.59%~5.08%,为尚清洁状态;坑塘沉积物有机质及总氮呈显著正相关但与总磷无相关性,表明沉积物总氮以有机氮为主要形态,总磷以无机磷为主要形态;TOC/TN表明坑塘沉积物中的有机质多来自于陆源污染。

关键词：沉积物氮磷空间分布风险评价