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Strangeness to increase the density of finite nuclear systems in constraining the high-density nuclear equation of state

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Nuclear Science and Techniques 2017年第12期28卷 244-247页

作者： Wei-Zhou Jiang rong-yong yang Si-Na Wei Department of Physics Southeast UniversityNanjing 211189China

As the high-density nuclear equation of state(EOS) is not very well constrained, we suggest that the structural properties from the finite systems can be used to extract a more accurate constraint. By including the strangeness degrees of freedom, the hyperon or anti-kaon, the finite systems can then have a rather high-density core which is relevant to the nuclear EOS at high densities directly. It is found that the density dependence of the symmetry energy is sensitive to the properties of multi-K hypernuclei, while the high-density EOS of symmetric matter correlates sensitively to the properties of kaonic nuclei.

关键词： Nuclear equation of state Relativistic meanfield theory Strangeness

Characteristics of Titanocene Catalyst Supported on Palygorskite for Ethylene Polymerization

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Chinese Chemical Letters 2006年第5期17卷 653-656页

作者： Xiao Wei YAN Jing Dai WANG Yi Bing SHAN yong rong yang Department of Chemical Engineering Zhejiang University Hangzhou 310027

A series of heterogeneous catalysts with Cp2TiCl2 supported on palygorskite were prepared and evaluated by ethylene slurry polymerizations. The so-called direct supported catalyst, for which the pretreatment of palygorskite with MAO or Al（i-Bu）3 was not necessary, gave the highest activity among these supported catalysts and could be more robust than homogeneous Cp2TiCl2. With the direct supported catalyst, no significant activity loss was observed under low Al/Ti molar ratios （Al/Ti=300） and the decay of polymerization rate was slower when compared to the other supported catalysts. It was found that the surface Lewis acidity of palygorskite after thermal treatment played an important role in activation of metallocene compound and resulted in high catalyst activity.

关键词： Playgorskite supported catalyst ethylene polymerization Lewis acidity.

Determination of particle size distribution by multi-scale analysis of acoustic emission signals in gas-solid fluidized bed

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第4期12卷 260-267页

作者： Cong-jing REN Jing-dai WANG Di SONG Bin-bo JIANG Zu-wei LIAO yong-rong yang State Key Laboratory of Chemical Engineering Department of Chemical and Biochemical Engineering Zhejiang University Hangzhou 310027 China

Particle size distribution(PSD) is an important parameter in the process of fluidization,and it always plays a crucial role in a gas-solid fluidized system.A PSD model for on-line PSD determination based on acoustic emission(AE) measurement was developed according to the mechanism of particle collision with the inner wall of the cylinder and multi-scale wavelet decomposition *** PSD model illuminates the quantitative relationship between the energy percentage of AE signals for different scales and the PSD,which indicates the feasibility of the application of the PSD *** were undertaken both in lab and plant gas-solid fluidized setup with polyethylene particles,and the parameters of the PSD model were calibrated and *** experimental conditions and results proved that the PSD model was suitable for on-line measurement and was sufficiently sensible and *** agglomeration,the PSD model also showed exact serviceability on detecting the onset of agglomeration by abnormal PSD,and the result agreed with that from the radiation ***,AE measurement was found to be a reliable and credible means for understanding the PSD information that affects the behavior of a system,which can provide valuable guidance for practical applications.

关键词： Particle size distribution(PSD) Acoustic emission(AE) Fluidized bed Multi-scale Agglomeration

Self-diffusion coefficients of organic solvents in linear and branched high density polyethylene particles measured by PFG NMR

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Chinese Chemical Letters 2008年第1期19卷 110-114页

作者： Xiao Wei Yan Xiao Hong Ren Siegfried Stap Jing Dai Wang yong rong yang Department of Chemical Engineering Zhejiang University Hangzhou 310027 China FG Technische Physik ll/Polymerphysik Fakultat fiir Mathematik und Naturwissenschaften Technische Universitiit Ilmenau Postfach 100565 D-98684 Ilmenau Germany Institut fiir Technische Chemie und Makromolekulare Chemie RWTH Aachen University Worringerweg 1 D-52056 Aachen Germany

Pulsed field gradient nuclear magnetic resonance （PFG NMR） has been performed to study the diffusion of organic solvents into semicrystalline polyethylene particles. Self-diffusion coefficients in different domains of the sample can be extracted through a bi- exponential fit to the echo intensity attenuation, which allows the precise determination of the tortuosity of the polyethylene particles. Further exploration comes from the measurements with branched polyethylene particles and it was found that the diffusion in polymer phase contributed significantly to the slow component of the exponential decay curve. 2007 Jing Dai Wang. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： Self-diffusion coefficients Pulsed field gradient NMR Tortuosity Polyethylene particle

Preparation of Aryloxy-aluminoxanes and Their Use as Activators in the Bis(imino)pyridyl Iron-catalyzed Oligomerization of Ethylene

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Chinese Journal of Polymer Science 2018年第11期36卷 1207-1207,1208-1216页

作者： Wei Zhang Bin-Bo Jiang Jian Ye Zu-Wei Liao Zheng-Liang Huang Jing-Dai Wang yong-rong yang Zhejiang Provincial Key Laboratory of Advanced Chemical Engineering Manufacture Technology State Key Laboratory of Chemical Engineering College of Chemical and Biological Engineering Zhejiang University

In this study, a series of aryloxy-aluminoxanes originated directly from the hydrolysis of reaction products of A1Me3 and phenols were synthesized, which could serve as effective polymer-retarding activators for the iron-catalyzed ethylene oligomerization. The molar ratios of [PhOH]/[AlMe3] and [H2O]/[Al] during the preparation were explored and their impacts on the oligomerization activity and product distribution were discussed. To obtain the effective activators with good polymer-retarding effect and relatively high activity, the optimized conditions were proposed to be [PhOH]/[AlMe3] = 0.5 and [H2O]/[Al] = 0.7. Various aluminoxanes with different [-OH] sources confirmed the importance of using phenols in preparing the effective polymer-retarding activators. By utilizing these aryloxy-aluminoxanes, the mass fraction of polymers in the total products could be reduced to lower than 1.0 wt%, which is much lower than that of the MAO-activated systems （〉 30 wt%）. This is a potential benefit for the industrial application of the iron-catalyzed oligomerization process.

关键词： Ethylene oligomerization Bis(imino)pyridyl iron catalysts Aryloxy-aluminoxanes Phenols Trimethylaluminum hydrolysis

Improved Biodegradation of 1,2,4-Trichlorobenzene by Adapted Microorganisms in Agricultural Soil and in Soil Suspension Cultures

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Pedosphere 2011年第4期21卷 423-431页

作者： SONG yang WANG Fang F. O. KENGARA BIAN yong-rong yang Xing-Lun LIU Cui-Ying JIANG Xin State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 (China) Department of Chemistry Maseno University Maseno 40105 (Kenya)

Inoculating soil with an adapted microbial community is a more effective bioaugmentation approach than inoculation with pure strains in ***,information on the potential of different inocula from sites with varying contamination levels and pollution histories in soil remediation is *** objective of the study was to investigate the potential of adapted microorganisms in soil inocula,with different contamination levels and pollution histories,to degrade 1,2,4-trichlorobenzene (1,2,4-TCB).Three different soils from chlorobenzene-contaminated sites were inoculated into agricultural soils and soil suspension cultures spiked with 1,2,*** results showed that 36.52% of the initially applied 1,2,4-TCB was present in the non-inoculated soil,whereas about 19.00% of 1,2,4-TCB was present in the agricultural soils inoculated with contaminated soils after 28 days of *** soils inoculated with adapted microbial biomass (in the soil inocula) showed higher respiration and lower 1,2,4-TCB volatilization than the non-inoculated soils,suggesting the existence of 1,2,4-TCB adapted degraders in the contaminated soils used for *** was further confirmed in the contaminated soil suspension cultures that the concentration of inorganic chloride ions increased continuously over the entire experimental *** contamination of the inocula led not only to higher degradation potential but also to higher residue ***,even inocula of low-level contamination were effective in enhancing the degradation of 1,2,***,applying adapted microorganisms in the form of soil inocula,especially with lower contamination levels,could be an effective and environment-friendly strategy for soil remediation.

关键词： bioaugmentation chlorobenzenes contaminated soil dechlorination inoculation volatilization

A congenital isolated left ventricular apical diverticulum simulating a tako-tsubo

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Chinese Medical Journal 2011年第2期124卷 315-317页

作者： WANG Mei LI yong-jun yang rong ZHANG Hui Department of Cardiology Second Hospital of Hebei Medical University Shijiazhuang Hebei 050000 China

Left ventricular diverticulum is a rare congenital anomaly of which the incidence was reported to be 0.26%. Diverticula are usually localized near the apex and most often involve the inferior or anterior parietal walls of the left ventricle. In this report, we describe a rare case of congenital isolated left ventricular apical diverticulum, which was tako-tsubo-like in systole, ＂dumbbell-like＂ the whole left ventricle, diagnosed by angiography and magnetic resonance imaging.

关键词： left ventricular diverticulum echocardiography angiograph magnetic resonance imaging

Hole-growth phenomenon during pyrolysis of a cation-exchange resin particle

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2022年第12期23卷 974-987页

作者： Zheng-liang HUANG Yun-bo YU Qi SONG Yao yang Jing-yuan SUN Jing-dai WANG yong-rong yang Zhejiang Provincial Key Laboratory of Advanced Chemical Engineering Manufacture Technology College of Chemical and Biological EngineeringZhejiangUniversityHangzhou 310027China State Key Laboratory of Chemical Engineering College of Chemical and Biological EngineeringZhejiang UniversityHangzhou 310027China

A novel central hole-expansion phenomenon is identified, in which the cation-exchange resin is pyrolyzed in a mixed atmosphere of nitrogen and oxygen at 400–500 ℃. In this reaction, the reaction path is predictable and always starts from the center of the resin particle to form a central hole, then continues and expands around the hole, finally forming a uniformly distributed hole group;the particle surface remains intact. Analysis shows that this formation mode is due to the different reaction paths of sulfonic groups between the surface and interior of the particle, caused by the temperature difference. On the surface, transformation reactions happen at high temperatures(410–500 ℃) to form stable organic sulfur structures, while decomposition occurs inside the particle at a relatively low temperature(<410 ℃) and promotes complete pyrolysis of the copolymer matrix to form holes.

关键词： Non-catalytic gas-solid reaction Cation-exchange resin Pyrolysis Central-hole expansion Temperature difference Transformation

模拟研究气液两相在带缩径管的90°弯管内的流动(英文)

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2017年第3期18卷 212-224页

作者： Dong-fang HU Zheng-liang HUANG Jing-yuan SUN Jing-dai WANG Zu-wei LIAO Bin-bo JIANG Jian yang yong-rong yang State Key Laboratory of Chemical Engineering College of Chemical and Biochemical Engineering Zhejiang University Hangzhou 310027 China Shanghai Key Laboratory of Catalysis Technology for Polyolefins Shanghai 200062 China

目的:90°弯管广泛应用于工业中的流体输送,但是流体在经过弯头时会由于离心力的作用而导致弯头下游管道内出现流体分布不均的现象,从而影响后续的生产过程。本文将实验和计算流体力学(CFD)模拟的方法结合研究缩径管对经过弯头后的流体... 详细信息

目的:90°弯管广泛应用于工业中的流体输送,但是流体在经过弯头时会由于离心力的作用而导致弯头下游管道内出现流体分布不均的现象,从而影响后续的生产过程。本文将实验和计算流体力学(CFD)模拟的方法结合研究缩径管对经过弯头后的流体整流作用并分析原因,以期为缩径管在工业中的应用提供一定的参考。创新点:1.提出在弯头后的管路中增加缩径管来调整流体的方法;2.在冷模实验数据验证模拟结果的正确性的基础上,根据CFD模拟得到的管道内的压力、流体速度、相分布及湍动能分布详细分析了缩径管能起整流作用的原因。方法:1.通过冷模实验所得的压力数据与模拟值进行对比,证明模拟所采用模型的正确性;2.通过对不同流体入口条件模拟结果的比较,找到缩径管的作用规律;3.通过CFD模拟得到管道内的压力、流体速度、相分布及湍动能,分析缩径管的整流原理。结论:1.模拟所采用的模型可较好地反映管道内的流体流动情况;2.缩径管能起到很好的整流效果;3.缩径管可使流体加速,促进流体的快速混合,因此能够使不稳定的流体快速达到稳定状态。

关键词： 90°弯管缩径管 CFD 均匀分布流体力学