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Influence of Excitation Frequency on Slosh-Induced Impact Pressures of Liquefied Natural Gas Tanks

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Journal of Shanghai Jiaotong university(science) 2011年第1期16卷 124-128页

作者：蔡忠华王德禹李喆 state key {2. of Ocean Engineering Shanghai Jiaotong University

Liquid sloshing phenomena in No.2.tank of 140 km 3 liquefied natural gas (LNG) carriers have been studied numerically and *** scale of the model tank was selected as 1/*** and pitch motions were *** measuring impact pressures,seventeen pressure sensors were installed on the tank model.A large number of excitation frequencies and filling heights were *** experimental results showed that when the frequency of tank motion is close to the natural frequency of fluid inside the tank,large impact pressures may be *** frequencies and maximum impact pressures of different filling height were *** all the experimental situations,the maximum impact pressure always occurs at the place near 70% height of tank where should be especially concerned.A computational fluid dynamics (CFD) model was developed to simulate the sloshing in the *** model was based on the Reynolds-averaged Navier-Stokes (RANS) equations,with a standard κ-ε turbulence *** volume of fluid (VOF) method was used to predict free surface *** mesh technique was used to update the volume *** for pressure time histories and peak pressures were compared to experimental *** agreement was observed.

关键词： sloshing liquefied natural gas (LNG) tanks impact pressure numerical simulation

Hierarchical Homochiral Assembly of Polyhedral Cage-Type Nanoclusters

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CCS Chemistry 2024年第10期6卷 2537-2548页

作者： Cheng-Long Deng Bao-Liang Han Ze-Yu Liu zhong-hua Pan Jiao He Yu-Long Li Zhi-Lin Yang Geng-Geng Luo Chen-Ho Tung Di Sun Lan-Sun Zheng key laboratory of Environmentally Friendly Function Materials Ministry of EducationCollege of Materials Science and EngineeringHuaqiao UniversityXiamen 361021 School of Chemistry and Chemical Engineering State Key Laboratory of Crystal MaterialsShandong UniversityJi’nan 250100 College of Physical science and technology Xiamen UniversityXiamen 361005 College of Chemistry and Environmental Engineering Sichuan University of Science and EngineeringZigong 643000 state key {2. for Physical Chemistry of Solid Surfaces Department of ChemistryCollege of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005

Hierarchical chiral self-assembly is of profound significance for biomolecules for their biological ***-precise metal nanoclusters(NCs)offer better opportunities to construct hierarchical ***,achieving hierarchical homochiral assembly of nanocrystals protected by achiral ligands has proven to be a formidable task,with existing examples primarily limited to heterochiral *** we put forward a hierarchical assembly strategy towards precisely fabricating highly ordered homochiral ***,clusterin-nanocage type copper-hydride NCs act as synthons,of which entity is featured with a hexagonal close-packed Cu_(9)kernel embedded in a C_(3)-symmetric trigonal-prismatic metallacage,leading to a chiral core-shell primary structure with either P or M *** four homochiral NCs combined with guests through synergistic noncovalent interactions spontaneously organize into a supramolecular tetrahedral secondary structure within a unit ***,these nanoscopic supramolecular motifs pack into tertiary hierarchical superlattice of chiral cubic crystalline ***,the crystalline material shows excellent robustness,and fascinating blueexcitable near-infrared thermally activated delayed fluorescence *** work not only exhibits that nanocage-type NCs can be smart as proteins to translate chiral primary structure into tertiary chiral hierarchical complexity,but also provides new insights into structure-to-superstructure,enabling bottom-up creation of higher-level hierarchical homochiral superlattice structures.

关键词： polyhydrido copper nanoclusters chiral polyhedral metallacage hierarchical homochiral assembly thermally activated delayed fluorescence

A COMBINED MEASUREMENT SYSTEM FOR UV/V IN SITU SPECTROELECTROCHEMICAL STUDY

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Chinese Chemical Letters 1991年第4期2卷 309-312页

作者： Jin LUO zhong hua LIN Zhao Wu TIAN ({2. key laboratory for Physical Chemistry of the Solid Surface,Xiamen university,Xiamen,361005)

A microcomputer-based UV/V in situ spectroelectrochemical measurement system has been *** paper presents a description of the experimental details regarding the methods and equipment.

关键词： UV A COMBINED MEASUREMENT SYSTEM FOR UV/V IN SITU SPECTROELECTROCHEMICAL STUDY

Overexpression of the transcription factor Sp8 induces ectopic motor neurons in the p3 domain of chick spinal cord

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Overexpression of the transcription factor Sp8 induces ectop...

中国神经科学学会第九届全国学术会议暨第五次会员代表大会

作者： Xiaosu LI~1,Chao LIN~1,Sijing SONG~2.Zhengang YANG~(1,*) 1 Institutes of Brain science and state {2. laboratory of Medical Neurobiology,Fudan university,Shanghai 2.0032. china 2.College of Life science and technology,hua zhong Agricultural university,wuhan 436700,{12.

＜正＞During the period of neurogenesis in the spinal cord,particular types of neurons are generated from specific progenitor cells located in different dorsoventral（DV） regions of the ventricular *** graded morphogens along the DV axis of the neural tube confer positional information to the progenitor *** achieve through induction or inhibition of a set of transcription factors expression in a concentration dependent *** combinatorial expression of distinct transcription factors,the DV axis of the neural tube can be divided into multiple domains and cross-repressive interactions between complementary pairs of transcription factors further refine and sharpen the boundaries between adjacent *** action of these transcription factors directs different progenitor populations to generate particular subtypes of ***8 is a zinc finger transcription factors belonging to specificity protein（Sp） family and expression of Sp8 in the basal plate of spinal cord has been *** there is no study addressing the function role of Sp8 during spinal cord *** the present study,we first confirmed Sp8 expression in the spinal cord using *** neurogenesis in the spinal cord,Sp8 expression shares the same ventral limit with O1ig2.and is complementary to Nkx2.2.O1ig2. domain and Nkx2.2. domain are neighboring with each other,and give rise to Isll+ motor neurons and Siml+ V3 interneurons respectively. When mouse Sp8 was overexpressed in the chick spinal cord using either retrovirus or in ovo electroporation,we found that ectopic motor neurons were induced in the Nkx2.2. p3 ***,Nkx2.2.expression was cellautonomously repressed by Sp8 *** suggests that Sp8 participates in patterning the ventral spinal cord.

关键词： Sp8 motor neuron Nkx2.2 dorsoventral patterning spinal cord

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HCCI汽油机混合燃烧及放热率计算模型

天津大学学报 2009年第11期42卷 997-1005页

作者：侯圣智谢辉陈韬胡顺堂赵华天津大学内燃机燃烧学国家重点实验室天津300072 天津大学内燃机研究所天津300072

火花辅助点火HCCI燃烧,是介于纯均质压燃着火燃烧以及传统火花点火燃烧这2.燃烧模式之间的一种特殊的燃烧模式.为此,在全可变气门机构HCCI单缸试验发动机上,研究了火花辅助点火SI-HCCI燃烧模式过渡过程的燃烧特征.通过对火花辅助点火对... 详细信息

火花辅助点火HCCI燃烧,是介于纯均质压燃着火燃烧以及传统火花点火燃烧这2.燃烧模式之间的一种特殊的燃烧模式.为此,在全可变气门机构HCCI单缸试验发动机上,研究了火花辅助点火SI-HCCI燃烧模式过渡过程的燃烧特征.通过对火花辅助点火对HCCI燃烧及混合燃烧影响规律的系统分析,提出了产生混合燃烧必须满足的温度条件,建立了由SI向HCCI切换的判断条件计算函数;结合SI函数、HCCI函数和切换条件函数,构建了能够描述混合燃烧过程的燃烧放热率计算模型,为SI-HCCI模式过渡控制策略研究提供了理论依据和技术手段.

关键词： HCCI汽油机混合放热率模式过渡

Research on the navigation method of large-scale differential tail-control improvised guided munitions based on rotational speed constraints

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Defence technology（防务技术） 2024年第8期38卷 155-170页

作者： Ning Liu Wenjiang Zhao Yao Wang Kai Shen zhong Su Wenhao Qi Yuedong Xie Beijing key laboratory of High Dynamic Navigation {2. Beijing Information Science and Technology UniversityBeijing100192China hua an Industry Group Co. Ltd.Qiqihar161006China Integrated Navigation and Intelligent Navigation laboratory Beijing Institute of TechnologyBeijing100081China Beijing Institute of technology Beijing100081China

In the process of launching guided projectile under the conventional system, it is difficult to effectively obtain the precise navigation parameters of the projectile in the high dynamic environment. Aiming at this problem, this paper describes a new system of guided ammunition based on tail spin reduction. After analyzing the mechanism of the ammunition's tail spin reduction, a navigation method of large scale difference tail control simple guided ammunition based on speed constraint is proposed. In this method,the corresponding navigation constraints can be carried out by combining the rotation speed state of the ammunition itself, and the optimal solution of navigation parameters during the flight of the missile can be obtained by Extended Kalman Filter(EKF). Finally, the performance of the proposed method was verified by the simulation environment, and the hardware-in-the-loop simulation test and flight test were carried out to verify the performance of the method in the real environment. The experimental results show that the proposed method can achieve the optimal estimation of navigation parameters for simple guided ammunition with large-scale difference tail control. Under the conditions of simulation test and hardware-in-loop simulation test, the position and velocity errors calculated by the method in this paper converged. Under the condition of flight test, the spatial average error calculated by the method described in this paper is 6.17 m, and the spatial error of the final landing point is 3.50 *** this method, the accurate acquisition of navigation parameters in the process of projectile launching is effectively realized.

关键词： Guided projectiles Tail spin reduction RPM constraints Combined navigation Extended Kalman filter(EKF)

Expression of Basic Fibroblast Growth Factor Results in the Decrease of Myostatin mRNA in Murine C2.12.Myoblasts

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Acta Biochimica et Biophysica Sinica 2006年第10期38卷 697-703页

作者： hua-zhong LIU~(1,2. Qing LI~1 Xing-Yuan YANG~1 Lin LIU~1 Lei LIU~1 Xiao-Rong AN~1* Yong-Fu CHEN~1 1 {2. key laboratory for Agrobiotechnology,College of Biological science,china Agricultural university,Beijing 100094,china 2.Modern Biochemistry Center,Guangdong Ocean university,Zhanjiang 52.088,china statekey{2.forAgrobiotechnology CollegeofBiologicalScienceChinaAgriculturalUniversityBeijing100094China ModernBiochemistryCenter GuangdongOceanUniversityZhanjiang524088China

During the development and regeneration of skeletal muscle,many growth factors,such asbasic fibroblast growth factor (bFGF,FGF-2. and myostatin,have been shown to play regulating *** contributes to promote proliferation and to inhibit differentiation of skeletal muscle,whereas myostatinplays a series of contrasting *** order to elucidate whether the expression of bFGF has any relationshipwith the expression of myostatin in skeletal muscle cells,we constructed a eukaryotic expression vector forthe expression of exogenous bFGF in murine C2.12.*** RT-PCR assays indicated thatwith the increase of the expression of exogenous bFGF gene,the expression of endogenous myostatin genewas suppressed at mRNA level and protein level.

关键词： basic fibroblast growth factor myostatin murine C2.12.myoblast real time RT-PCR

气体介质与脉冲参数对纳秒脉冲放电特性的影响

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燃烧科学与技术 2024年第2期30卷 187-195页

作者：钟郑涛陈韬何邦全赵华天津大学先进内燃动力全国重点实验室天津300072

在定容弹内研究了介质压力、介质成分以及纳秒脉冲电源所控制的4个脉冲参数(脉冲输出电压、脉冲宽度、脉冲次数、脉冲频率)对纳秒脉冲放电过程的影响.结果表明:介质压力上升,首个脉冲和首个击穿脉冲的电极释放电压均上升,高压维持数增加... 详细信息

在定容弹内研究了介质压力、介质成分以及纳秒脉冲电源所控制的4个脉冲参数(脉冲输出电压、脉冲宽度、脉冲次数、脉冲频率)对纳秒脉冲放电过程的影响.结果表明:介质压力上升,首个脉冲和首个击穿脉冲的电极释放电压均上升,高压维持数增加,首个击穿脉冲的放电能量上升.增大脉冲输出电压可以减少高压维持数,但不改变击穿电压.增大脉冲宽度同样不改变击穿电压,但明显提升了首个击穿脉冲的放电能量.改变容弹内介质中CO_(2.的浓度,首个脉冲和首个击穿脉冲的释放电压、放电能量、高压维持数均增加.升高脉冲频率增强了在不同环境条件下脉冲击穿能力,但不影响能量注入总量.在确保击穿的情况下,脉冲次数的增加则能显著增大脉冲注入的能量,增大粒子云团面积,有助于实际点燃过程.

关键词：纳秒脉冲放电等离子体纹影法放电介质

New sustainable polymers with on-demand depolymerization property

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science china Chemistry 2024年第9期67卷 2803-2841页

作者： Yangyang Sun Zesheng An Yanshan Gao Rongrong Hu Ye Liu hua Lu Xiao-Bing Lu Xuan Pang Anjun Qin Yong Shen Youhua Tao Yu-{2. Wang Junpeng Wang Gang Wu Guang-Peng Wu Tie-Qi Xu Xing-Hong Zhang Yuetao Zhang Zhenbiao Zhang Jian-Bo Zhu Miao Hong Zhibo Li state key {2. of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China state key {2. Base of Eco-Chemical Engineering College of Chemical EngineeringQingdao University of Science and TechnologyQingdao266042China state key {2. of Supramolecular Structure and Materials College of ChemistryJilin UniversityChangchun 130012China state key {2. of Luminescent Materials and Devices Guangdong Provincial Key Laboratory of Luminescence from Molecular AggregatesSouth China University of TechnologyGuangzhou 510640China state key {2. of Fine Chemicals Frontiers Science Center for Smart MaterialsDalian University of TechnologyDalian 116024China Beijing National laboratory for Molecular sciences Center for Soft Matter Science and EngineeringKey Laboratory of Polymer Chemistry and Physics of Ministry of EducationCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China key laboratory of Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China The Collaborative Innovation Center for Eco-Friendly and Fire-Safety Polymeric Materials(MoE) National Engineering Laboratory of Eco-Friendly Polymeric Materials(Sichuan)College of ChemistryState Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu 610064China School of Polymer science and Polymer Engineering the University of AkronAkronOH 44325USA MOE key laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and EngineeringZhejiang UniversityHangzhou 310027China state and Local Joint Engineering laboratory for Novel Functional Polymeric Materials Jiangsu Key Laboratory of Advanced Functional Polymer Design and ApplicationSuzhou Key Laboratory of Macromolecular Design and Precision SynthesisCollege of ChemistryChemical Engineering and Materials ScienceSoochow UniversitySuzhou 215123China

To combat the crisis of today's synthetic polymers arising from unsustainable production and disposal,it is essential for the synthetic polymer community to reshape the current polymer industry with sustainable *** an emerging class of sustainable polymers,the development of chemically depolymerizable polymers(CDPs),which can undergo closed-loop depolymerization/repolymerization cycles to reproduce virgin polymers without the loss of properties from recovered monomers,offers an ideal solution to preserve finite natural resources,provides a feasible solution to the end-of-life issue of polymer waste,and thereby establishes a circular materials ***,two grand key challenges have been encountered in the establishment of practically useful CDPs:how to balance polymerization and depolymerization ability and how to unify conflicted depolymerizability and physical ***,this critical review article presents our vision for summarizing feasible strategies to overcome the above two significant challenges and the design principles for constructing an ideal CDP by highlighting selected major progress made in this rapidly expanding field.

关键词： chemically depolymerizable polymers sustainable polymers depolymerization monomer recovery degradation plastics