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Effect of hydrogen bonding and hydrophobic interaction on the formation of supramolecular hydrogels formed by L-phenylalanine derivative hydrogelator

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Chinese Chemical Letters 2007年第8期18卷 1001-1004页

作者： Xin jian fu Shu qin Cao Ning Xia Wang Sheng Zu Zhang Hong wang Ya jiang Yang Department of Chemistry Huazhong University of Science and Technology Wuhan 430074 China

A new hydrogelator, pyridinium bromide salt of N-6-bromohexanoyl-L-phenylamino octadecane, was synthesized. Supramolecular hydrogels can be formed through the self-assembly of this hydrogelator in water. In this work, D2O was used instead of H2O as solvent for FT-IR measurement due to the fact that it is impossible to obtain useful Fr-IR information on the hydrogen bonding in water. The investigation of PT-IR and steady-state fluorescence indicated that the driving forces for the self-assembly were mainly hydrogen bonding and hydrophobic interaction. Based on the data of XRD and molecular modeling, the possible mechanism of the formation of hydrogelator aggregates was proposed.

关键词： t-Phenylalanine derivatives Hydrogelator Supramolecular hydrogels

An approach for IC engine coolant energy recovery based on low-temperature organic Rankine cycle

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Journal of Central South University 2015年第2期22卷 727-734页

作者：付建勤刘敬平徐政欣邓帮林刘琦 Research Center for Advanced Powertrain Technology Hunan University

To promote the fuel utilization efficiency of IC engine, an approach was proposed for IC engine coolant energy recovery based on low-temperature organic Rankine cycle(ORC). The ORC system uses IC engine coolant as heat source, and it is coupled to the IC engine cooling system. After various kinds of organic working media were compared, R124 was selected as the ORC working medium. According to IC engine operating conditions and coolant energy characteristics, the major parameters of ORC system were preliminary designed. Then, the effects of various parameters on cycle performance and recovery potential of coolant energy were analyzed via cycle process calculation. The results indicate that cycle efficiency is mainly influenced by the working pressure of ORC, while the maximum working pressure is limited by IC engine coolant temperature. At the same working pressure, cycle efficiency is hardly affected by both the mass flow rate and temperature of working medium. When the bottom cycle working pressure arrives at the maximum allowable value of 1.6 MPa, the fuel utilization efficiency of IC engine could be improved by 12.1%.All these demonstrate that this low-temperature ORC is a useful energy-saving technology for IC engine.

关键词： IC engine waste heat recovery organic Rankine cycle cycle efficiency coolant energy

新一代连续带钢真空镀膜技术的发展现状与展望

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钢铁 2007年第4期42卷 1-4页

作者：杨立红张健傅建钦崔健上海宝钢股份有限公司研究院上海201900

介绍了新一代连续带钢镀膜技术——真空镀膜的工艺特点及应用现状。热蒸发喷射、磁控溅射、电子束蒸发和等离子增强型电子束蒸发是目前最接近工业化的连续带钢真空镀膜工艺,并在多家钢铁公司的真空镀膜中试线上得到了应用。其工艺特点... 详细信息

介绍了新一代连续带钢镀膜技术——真空镀膜的工艺特点及应用现状。热蒸发喷射、磁控溅射、电子束蒸发和等离子增强型电子束蒸发是目前最接近工业化的连续带钢真空镀膜工艺,并在多家钢铁公司的真空镀膜中试线上得到了应用。其工艺特点是环保、良好的薄膜综合性能和可沉积材料的多样性及工艺组合的多样性,其镀层系统主要包括现有产品表面改性、极端环境应用镀层、环保高效的中间层系统以及新型多功能薄膜和复合薄膜。该技术目前正在走向工业化。工业化应用面临的主要问题是产品和市场定位问题。

关键词：带钢真空镀膜工艺工业化多功能镀层

Quantum public-key crypto via EPR pairs

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 58-63页

作者： Xiang-Qun fu Hong-Wei Li jian-Hong Shi Tan Li Wan-Su Bao Henan Key Laboratory of Quantum Information and Cryptography Information Engineering University Synergetic Innovation Center of Quantum Information and Quantum Physics University of Science and Technology of China

With the development of quantum computing technology, quantum public-key cryptography is gradually becoming an alternative to the existing classical public-key cryptography. This paper designs a quantum trapdoor one-way function via EPR pairs and quantum measurements. Based on this, a new quantum public-key cryptosystem is presented, which offers forward security,and can resist the chosen-plaintext attack and chosen-ciphertext attack. Compared with the existing quantum public-key cryptos,eavesdropping can be automatically detected in this new quantum public-key cryptosystem under a necessary condition, which is also detailed in the paper.

关键词： quantum public-key crypto trapdoor one-way function EPR pairs

Bacterial indole-3-propionic acid inhibits macrophage IL-1β production through targeting methionine metabolism

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Science China Life Sciences 2025年

作者： Ziyi Han jian fu Aiyan Gong Wenkai Ren State Key Laboratory of Livestock and Poultry Breeding College of Animal Science South China Agricultural University Animal Disease-resistant Nutrition Key Laboratory of Sichuan Province Sichuan Agricultural University China Institute of Veterinary Drug Control

The gut microbiota plays key roles in host health by shaping the host immune responses through their metabolites, like indole derivatives from tryptophan. However, the direct role of these indole derivatives in macrophage fate decision and the underlying mechanism remains unknown. Here, we found that bacterial indole-3-propionic acid(IPA) downregulates interleukin-1beta(IL-1β) production in M1 macrophages through inhibition of nuclear factor-kappa B(NF-κB) signaling. Mechanistically, IPA binds specifically with methionine adenosyltransferase 2A(MAT2A) to promote S-adenosylmethionine(SAM) synthesis, which facilitates the DNA methylation of ubiquitin-specific peptidase 16(USP16, a deubiquitinase), and in turn promotes Toll-like receptor 4(TLR4) ubiquitination and NF-κB inhibition. furthermore,IPA administration attenuates sepsis in mouse models induced by lipopolysaccharides(LPS), showcasing its potential as a microbial-derived adjunct in alleviating inflammation. Collectively, our findings reveal a newly found microbial metabolite-immune system regulatory pathway mediated by IPA.

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高速柴油机动力及排放性能与运行参数之间的共性规律

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内燃机学报 2014年第3期32卷 223-229页

作者：夏言刘敬平袁志鹏付建勤湖南大学先进动力总成技术研究中心湖南长沙410082 湖南奔腾动力科技有限公司湖南长沙410000

为给新品发动机性能概念设计阶段的参数定义提供优化方向,基于先进发动机性能对标技术,对4台车用高速柴油机稳态工况下的运行参数、性能参数以及排放水平进行了全面的检测.通过对实测数据的二次开发与分析,提炼出影响柴油机动力性的进... 详细信息

为给新品发动机性能概念设计阶段的参数定义提供优化方向,基于先进发动机性能对标技术,对4台车用高速柴油机稳态工况下的运行参数、性能参数以及排放水平进行了全面的检测.通过对实测数据的二次开发与分析,提炼出影响柴油机动力性的进气参数K和影响柴油机源排放的缸内稀释参数L.结果表明:进气参数K与动力性指标的关系,以及缸内稀释参数L与源排放的关系在不同柴油机及同一柴油机不同工况之间有着良好的共性规律.应用分析结果,可针对新品柴油机开发需求,确定各工况下主要运行参数的取值范围.

关键词：柴油机运行参数共性规律动力性能排放

LNG发动机低速工况下瞬态燃烧过程试验研究

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湖南大学学报（自然科学版） 2016年第2期43卷 64-69页

作者：付建勤刘敬平阳辉勇徐伟廖诚湖南大学汽车车身先进设计制造国家重点实验室湖南长沙410082 湖南大学先进动力总成技术研究中心湖南长沙410082

对一台增压、液化天然气（LNG）发动机低速工况下的瞬态过程进行连续检测,将实测的瞬态缸压曲线进行二次处理,得出表征缸内燃烧过程的特征参数,在此基础上剖析了诸多瞬态燃烧特征参数的内在联系以及对LNG发动机性能的影响.结果表明,50%... 详细信息

对一台增压、液化天然气（LNG）发动机低速工况下的瞬态过程进行连续检测,将实测的瞬态缸压曲线进行二次处理,得出表征缸内燃烧过程的特征参数,在此基础上剖析了诸多瞬态燃烧特征参数的内在联系以及对LNG发动机性能的影响.结果表明,50%燃烧点位置随循环数变动范围约为5 oCA,其波动主要是由燃烧始点的变化引起的,50%燃烧点和燃烧始点的峰值（或谷值）相互对应;50%燃烧点的峰值对应着最高压力升高率和最高爆发压力的谷值,反之则相反.10%~90%燃烧持续期的变化范围为30~45 oCA,它随循环数上升是导致LNG发动机IMEP和NMEP下降的主要原因之一.燃烧特征参数的波动,主要归咎于燃烧始点的不稳定.实现对燃烧始点的精准控制,是保证LNG发动机在低速高增压瞬态过程具有较好工作稳定性的前提.

关键词：天然气发动机瞬态工况燃烧台架试验

蒸汽辅助涡轮对增压汽油机瞬态响应特性影响的模拟

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湖南大学学报（自然科学版） 2015年第4期42卷 13-18页

作者：付建勤刘敬平陈玉龙邓帮林徐伟湖南大学汽车车身先进设计制造国家重点实验室湖南长沙410082 湖南大学先进动力总成技术研究中心湖南长沙410082

为改善废气涡轮增压汽油机加速工况时的瞬态响应特性,提出了蒸汽辅助涡轮增压的方法.基于一款废气涡轮增压汽油机,采用GT-Power软件分别建立并标定了蒸汽辅助涡轮增压与废气涡轮增压的仿真模型.针对该汽油机的常用转速2000r/min,研究了... 详细信息

为改善废气涡轮增压汽油机加速工况时的瞬态响应特性,提出了蒸汽辅助涡轮增压的方法.基于一款废气涡轮增压汽油机,采用GT-Power软件分别建立并标定了蒸汽辅助涡轮增压与废气涡轮增压的仿真模型.针对该汽油机的常用转速2000r/min,研究了各种蒸汽参数对增压系统及汽油机性能的影响.结果表明,在2000r/min时的加速工况,蒸汽辅助涡轮能使汽油机加速迟滞时间缩短48.0%,加速扭矩提升9.7%.因此,蒸汽辅助涡轮能有效改善增压汽油机的加速性和动力性.

关键词：汽油机涡轮增压余热回收瞬态响应涡轮迟滞

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余热气化甲醇燃料对内燃机性能的影响

湖南大学学报（自然科学版） 2014年第3期41卷 31-36页

作者：付建勤刘敬平邓帮林周峰朱国辉湖南大学先进动力总成技术研究中心湖南长沙410082

提出了采用内燃机废气余热气化甲醇,并将该方案同时应用在自然吸气和增压发动机上.通过将这两种方案与原汽油机进行对比,预测这两种方案对发动机动力性和经济性的改善潜力.结果表明:甲醇蒸汽发动机在外特性下功率较原汽油机最大下降了7.... 详细信息

提出了采用内燃机废气余热气化甲醇,并将该方案同时应用在自然吸气和增压发动机上.通过将这两种方案与原汽油机进行对比,预测这两种方案对发动机动力性和经济性的改善潜力.结果表明:甲醇蒸汽发动机在外特性下功率较原汽油机最大下降了7.1%,热效率最大提高了3.0个百分点;增压后,动力性和经济性较原汽油机和甲醇蒸汽发动机都有较大提高,当增压压力为0.15MPa时热效率较原汽油机最大可提高4.0个百分点,表明余热气化甲醇在内燃机上具有较好的节能潜力.

关键词：内燃机代用燃料甲醇发动机涡轮增压余热回收