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采用激光诱导荧光法测量油膜厚度的研究

内燃机学报 2008年第1期26卷 92-95页

作者：陆霄露邓康耀上海交通大学动力机械与工程教育部重点实验室上海200240

激光诱导荧光(Laser Induced Fluorescence,LIF)技术是一种先进的测量微米级油膜厚度的方法,可用于研究燃油附壁现象。通过标定试验,找到了把荧光信号转化为油膜厚度的方法,同时还分析了背景光以及激光脉冲照射对标定试验的影响。另外,... 详细信息

激光诱导荧光(Laser Induced Fluorescence,LIF)技术是一种先进的测量微米级油膜厚度的方法,可用于研究燃油附壁现象。通过标定试验,找到了把荧光信号转化为油膜厚度的方法,同时还分析了背景光以及激光脉冲照射对标定试验的影响。另外,为了保证喷油器、激光器以及示波器的同步工作,设计了一个控制器。在此基础上对石英平板上的油膜厚度进行了测量,得到了油膜厚度在空间与时间上的分布曲线,验证了采用激光诱导荧光法测量油膜厚度的可行性和有效性。

关键词：激光诱导荧光燃油附壁油膜厚度

Effects of reducing dietary protein on the expression of nutrition sensing genes(amino acid transporters) in weaned piglets

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2015年第6期16卷 496-502页

作者： Li WU Liu-qin HE Zhi-jie CUI Gang LIU kang yao Fei WU Jun LI Tie-jun LI Research Center of Healthy Breeding of Livestock and Poultry Hunan Engineering and Research Center of Animal and Poultry ScienceKey Laboratory of Agro-ecological Processes in Subtropical RegionInstitute of Subtropical AgricultureChinese Academy of Sciences

The effects of crude protein（CP） levels in the diet on the m RNA expression of amino acid（AA） transporters were studied in a 45-d trial. Eighteen piglets with an initial body weight（BW） of 9.57 kg were assigned to three groups（14%, 17%, and 20% CP in the diet） in a completely randomized design（six replicates per treatment）. Diets were supplemented with crystalline AA to achieve equal standardized ileal digestible contents of Lys, Met plus Cys, Thr, and Trp, and were provided ad libitum. After 45 d, all piglets were slaughtered to collect small intestine samples. Compared with the values in the 14% CP group, the expressions of ASCT2, 4F2 hc, and ATB0 m RNA in the jejunum were increased by 23.00%, 12.00%, 6.00% and 48.00%, 47.00%, 56.00% in the 17% and 20% CP groups, respectively. These results indicate that a 14% CP diet supplemented with crystalline AA may not transport enough AA into the body and maintain growth performance of piglets. However, a reduction of dietary 17% CP may reduce the excretion of nitrogen into the environment while supporting the development of piglets. Therefore, the 17% CP level is more suitable than 14% CP level.

关键词： Crude protein Amino acid balance Amino acid transporters

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感兴趣系数图像压缩编码算法

电子与信息学报 2006年第5期28卷 844-847页

作者：邓家先康耀红海南大学信息学院海口570228

根据遥感图像编码的特殊性,提出了一种感兴趣系数编码算法。对于给定码率计算遥感图像小波域系数的熵估计值,从而大致确定正常编码情况下图像编码所截取到的比特平面,在此基础上给出了感兴趣系数确定方案及提升幅度的计算方法。该算法... 详细信息

根据遥感图像编码的特殊性,提出了一种感兴趣系数编码算法。对于给定码率计算遥感图像小波域系数的熵估计值,从而大致确定正常编码情况下图像编码所截取到的比特平面,在此基础上给出了感兴趣系数确定方案及提升幅度的计算方法。该算法与感兴趣区域编码方法不同,不需要在图像域指定感兴趣区域,系数提升幅度也不用提前指定,而且不必对所有子带的系数进行提升。该算法是任意区域的感兴趣区域编码的扩展和补充,但更为灵活、有效。仿真结果表明该算法可以有效保留遥感图像中小目标的信息,但图像总体质量略有下降。

关键词：图像处理图像压缩感兴趣系数熵估计值比特平面提升

Synthesis of N-methylene phosphonic chitosan(NMPCS)and its potential as gene carder

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Chinese Chemical Letters 2007年第11期18卷 1407-1410页

作者： Dun Wan Zhu Jin Gen Bo Hai Ling Zhang Wen Guang Liu Xi Gang Leng Cun Xian Song Yu Ji Yin Li Ping Song Lan Xia Liu Lin Mei Xiu Lan Li Yang Zhang kang De yao Research Institute of Polymeric Materials Tianjin University Tianjin 300072 China Tianjin Key Laboratory of Biomedical Materials Institute of Biomedical Engineering Chinese Academy of Medical Sciences ＆ Peking Union Medical College Tianjin 300192 China Institute of Orthopedics Tianjin Hospital Tianjin 300211 China

N-Methylene phosphonic chitosan （NMPCS）, an amphiphilic macromolecule with powerful chelating ability of Ca^2＋ ions, was synthesized and characterized. The physicochernical properties of NMPCS and the interactions between NMPCS and plasmid DNA were investigated by FTIR, ^13C NMR, X-ray, agarose gel electrophoresis retardation assay, atomic force microscopy （AFM） and circular dichroism （CD）. The results suggest that at charge ratio 2：1 or above, DNA could be completely entrapped and spherical complexes with mean size of 80-210 nm were formed. Taking HeLa as host cell, luciferase expression mediated by NMPCS improved about 100 times compared to the expression mediated by chitosan.

关键词： Non-viral vector Gene delivery N-Methylene phosphonic chitosan

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柴油机起动倒拖缸内喷雾仿真分析

内燃机工程 2015年第1期36卷 92-99页

作者：彭海勇崔毅邓康耀上海交通大学动力机械与工程教育部重点实验室上海200240

采用三维CFD数值模拟的方法,对试验发动机冷机起动倒拖时的缸内燃油喷射雾化过程进行了仿真计算分析。研究结果表明:在燃油喷雾过程中,由于燃油蒸发吸热,导致缸内温度明显下降,与不喷油时相比下降了32K;缸内喷雾过程出现大量的燃油附壁... 详细信息

采用三维CFD数值模拟的方法,对试验发动机冷机起动倒拖时的缸内燃油喷射雾化过程进行了仿真计算分析。研究结果表明:在燃油喷雾过程中,由于燃油蒸发吸热,导致缸内温度明显下降,与不喷油时相比下降了32K;缸内喷雾过程出现大量的燃油附壁,附壁量占总喷油量的70%左右;喷雾过程结束时形成的混合气浓度场和温度场呈极不均匀的分层分布,浓度较高的区域温度较低,且分布于靠近活塞壁面的薄层,不利于焰前反应的进行。这些因素均对冷起动过程缸内混合气的着火燃烧产生关键性的影响。此外,研究结果还表明,喷油油束速度是冷起动条件下影响缸内油滴蒸发过程的重要因素。

关键词：内燃机柴油机冷起动喷油过程仿真计算

Collaborative optimization of exhaust gas recirculation and Miller cycle of two-stage turbocharged marine diesel engines based on particle swarm optimization

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Journal of Central South University 2022年第7期29卷 2142-2156页

作者： TANG Xu-yang WANG Peng ZHANG Zhong-yuan ZHANG Feng-li SHI Lei DENG kang-yao School of Mechanical Engineering Shanghai Jiao Tong UniversityShanghai 200240China WeiChai Power Co. Ltd.Weifang 261001China

To meet increasingly stringent emission standards and lower the brake-specific fuel consumption(BSFC)of marine engines,a collaborative optimization study of exhaust gas recirculation(EGR)and a Miller cycle coupled turbocharging system was carried *** this study,a one-dimensional numerical model of the EGR,Miller cycle,and adjustable two-stage turbocharged engine based on WeiChai 6170 marine diesel engine was *** particle swarm optimization algorithm was used to achieve multi-input and multi-objective comprehensive optimization,and the effects of EGR-coupled Miller regulation and high-pressure turbine bypass regulation on NO_(x)and BSFC were *** results showed that a medium EGR rate-coupled medium Miller degree was better for the comprehensive optimization of NO_(x)and *** medium EGR rate and low turbine bypass rates,NO_(x)and BSFC were relatively balanced and ***,an optimal steady-state control strategy under full loads was *** an increase in loads,the optimized turbine bypass rate and Miller degree gradually *** with the EGRonly system,the optimal system of EGR and Miller cycle coupled turbine bypass reduced NO_(x)by 0.87 g/(kW·h)and BSFC by 17.19 g/(kW·h)at 100%***,the EGR and Miller cycle coupled adjustable two-stage turbocharging achieves NO_(x)and BSFC optimization under full loads.

关键词： exhaust gas recirculation(EGR) Miller cycle NO_(x)emissions adjustable two-stage turbocharging particle swarm optimization

TiC/Ni固液界面异质形核行为的第一性原理分子动力学模拟

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中国有色金属学报 2024年第8期34卷 2673-2683页

作者：王文菲康瑶黄盛星黄昊王旭东姚曼大连理工大学材料科学与工程学院大连116024

本文借助第一性原理分子动力学方法和密度泛函理论,针对四种TiC/Ni固液界面,从原子的异质形核行为与界面的电子性质两方面综合分析,进一步研究TiC促进Ni异质形核的机制。结果表明:TiC(100)、[Ti]-TiC(111)、[C]-TiC(111)基底均可诱导出N... 详细信息

本文借助第一性原理分子动力学方法和密度泛函理论,针对四种TiC/Ni固液界面,从原子的异质形核行为与界面的电子性质两方面综合分析,进一步研究TiC促进Ni异质形核的机制。结果表明:TiC(100)、[Ti]-TiC(111)、[C]-TiC(111)基底均可诱导出Ni的预形核层(Pre-nucleation layer,PNL),且界面PNL的层间及面内有序度排序均为:[Ti]-TiC(111)/Ni>[C]-TiC(111)/Ni>TiC(100)/Ni。[Ti]-TiC(111)与PNL的Ni原子之间的强相互作用及化学键合使得其诱导出的PNL有序度最高。而TiC(110)基底无法诱导液体Ni原子形成预形核层,相较于上述三种基底,其促进Ni原子形核的能力最弱。在降温过程中,液相中剩余的Ni原子通过在TiC(100)、[Ti]-TiC(111)及[C]-TiC(111)基底诱导出的PNL作为过渡层的基础上,随温度的降低在PNL外侧聚集成簇,形成稳定的晶核。

关键词： TiC/Ni固液界面预形核层异质形核第一性原理分子动力学模拟

不同EGR方法对柴油燃料HCCI燃烧影响的探讨

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内燃机学报 2005年第5期23卷 463-468页

作者：石磊邓康耀崔毅刘宇上海交通大学动力机械与工程教育部重点实验室上海200030

研究了内部EGR和外部EGR模式对柴油燃料HCCI燃烧的影响.随着内部EGR率的增大,HCCI燃烧的着火始点提前,在相对较小的负荷下,-40℃A气门重叠期的着火始点比-20℃A气门重叠期的着火始点提前5～7℃A,内部EGR的加热作用大于其对混合气的稀释... 详细信息

研究了内部EGR和外部EGR模式对柴油燃料HCCI燃烧的影响.随着内部EGR率的增大,HCCI燃烧的着火始点提前,在相对较小的负荷下,-40℃A气门重叠期的着火始点比-20℃A气门重叠期的着火始点提前5～7℃A,内部EGR的加热作用大于其对混合气的稀释作用;内部EGR增大有利于均质混合气的形成,使柴油燃料HCCI燃烧的烟度排放减小,但使低NOx排放的负荷范围减小;外部EGR起到了推迟着火始点的作用,是一种有效的扩展运行范围负荷上限的方法.

关键词：柴油机 HCCI 燃烧特性 EGR

High glucose induces upregulation of scavenger receptors and promotes maturation of dendritic cells

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High glucose induces upregulation of scavenger receptors and...