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Mechanical property of artificial methane hydrate under triaxial compression

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Journal of Natural Gas Chemistry 2010年第3期19卷 246-250页

作者： Yongchen song Feng yu Yanghui li Weiguo liu Jiafei Zhao Key Laboratory of Ocean Energy Utilization and Energy Conservation of Ministry of Education Dalian University of Technology Dalian 116024 Liaoning China

Methane production from hydrate reservoir may induce seabed slide and deformation of the hydrate-bearing *** research on mechanical properties of methane hydrate is considered to be important for developing an efficient methane exploitation *** this paper,a triaxial test system containing a pressure crystal device was developed with the conditions to stabilize the hydrate.A series of triaxial shear tests were carried out on artificial methane hydrate *** addition,mechanical characteristics of methane hydrate were studied with the strain rates of 0.1 and 1.0 mm/min,respectively,under the conditions of different temperatures（T =-5,-10,and-20 ℃） and confining pressures（P = 0,5,10,15,and 20 MPa）.The preliminary results show that when the confining pressure was less than 10 MPa,the increase of confining pressure leaded to the enhancement of shear ***,the decreasing temperature and the increasing strain rate both caused the increase in shear strength.

关键词： triaxial mechanical properties confining pressure temperature strain rate

Resynchronization and remultiplexing for transcoding to H.264/AVC

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第Z1期7卷 76-81页

作者： ZHOU Jin XIONG Hong-kai song li yu song-yu Institute of Image Communication and Information Processing Shanghai Jiao Tong University Shanghai 200030 China Institute of Image Communication and Information Processing Shanghai Jiao Tong University Shanghai 200030 China Institute of Image Communication and Information Processing Shanghai Jiao Tong University Shanghai 200030 China Institute of Image Communication and Information Processing Shanghai Jiao Tong University Shanghai 200030 China

H.264/MPEG-4 AVC standard appears highly competitive due to its high efficiency, flexibility and error resilience. In order to maintain universal multimedia access, statistical multiplexing, or adaptive video content delivery, etc., it induces an immense demand for converting a large volume of existing multimedia content from other formats into the H.264/AVC format and vice versa. In this work, we study the remultiplexing and resynchronization issue within system coding after transcoding, aiming to sustain the management and time information destroyed in transcoding and enable synchronized decoding of decoder buffers over a wide range of retrieval or receipt conditions. Given the common intention of multiplexing and synchronization mechanism in system coding of different standards, this paper takes the most widely used MPEG-2 transport stream (TS) as an example, and presents a software system and the key technologies to solve the time stamp mapping and relevant buffer management. The solution reuses previous information contained in the input streams to remultiplex and resynchronize the output information with the regulatory coding and composition structure. Experimental results showed that our solutions efficiently preserve the performance in multimedia presentation.

关键词： Transport stream (TS), Remultiplex, Time stamp, Transcoding, H.264/AVC

Diterpenoid Alkaloids from the Aerial Parts of Aconitum flavum Hand.-Mazz

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Natural Products and Bioprospecting 2021年第4期11卷 421-429页

作者： Na Zhang Fan Xia song-yu li Yin Nian li-Xin Wei Gang Xu State Key Laboratory of Phytochemistry and Plant Resources in West China and yunnan Key Laboratory of Natural Medicinal Chemistry Kunming Institute of BotanyChinese Academy of SciencesKunming 650201China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Tibetan Medicine Research and Qinghai Provincial Key Laboratory of Tibetan Medicine Pharmacology and Safety Evaluation Northwest Institute of Plateau BiologyChinese Academy of SciencesXiningQinghaiChina

Sixteen diterpenoid alkaloids(DAs),including six aconitine-type alkaloids(5 and 9−13),seven 7,17-seco-aconitine-type alkaloids(1−4,6−8),two napelline-type alkaloids(14 and 15)as well as one veatchine-type alkaloid(16),were isolated from the aerial parts of Aconitum flavum Hand.-*** which,flavumolines A−D(1−4)were four new ones,and flavu-moline E(5)was reported as natural compound for the first *** chemical structures were elucidated by the analysis of extensive spectroscopic *** inhibitory activities of these isolates on Cav3.1 low voltage-gated Ca^(2+)channel,NO production in LPS-activated RAW264.7cells,five human tumor cell lines,as well as acetylcholinesterase(AChE)were tested.

关键词： Aconitum flavum Hand.-Mazz Diterpenoid alkaloids Bioactivity

Isoprenylated Flavonoids as Cav3.1 Low Voltage-Gated Ca^(2+)Channel Inhibitors from Salvia digitaloides

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Natural Products and Bioprospecting 2021年第6期11卷 671-678页

作者： Jian-Jun Zhao song-yu li Fan Xia Ya-li Hu Yin Nian Gang Xu State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of Sciencesand Yunnan Key Laboratory of Natural Medicinal ChemistryKunming 650201People’s Republic of China University of Chinese Academy of Sciences Beijing 100049People’s Republic of China

Saldigones A-C(1,3,4),three new isoprenylated flavonoids with diverse flavanone,pterocarpan,and isoflavanone architec-tures,were characterized from the roots of Salvia digitaloides,together with a known isoprenylated flavanone(2).Notably,it’s the first report of isoprenylated flavonoids from Salvia *** structures of these isolates were elucidated by extensive spectroscopic *** of the compounds were evaluated for their activities on Cav3.1 low voltage-gated Ca^(2+)channel(LVGCC),of which 2 strongly and dose-dependently inhibited Cav3.1 peak current.

关键词： Salvia digitaloides Isoprenylated flavonoid Cav3.1 low voltage-gated Ca^(2+)channel(LVGCC)

Blind　Equalization　Based　on　Evolution　Strategies

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通信学报 1997年第3期18卷 60-64页

作者： song yu Zhang Xianda li Yanda (Dept Automation,Tsinghua University, Beijing 100084)

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ＢｌｉｎｄＥｑｕａｌｉｚａｔｉｏｎＢａｓｅｄｏｎＥｖｏｌｕｔｉｏｎＳｔｒａｔｅｇｉｅｓＳｏｎｇＹｕＺｈａｎｇＸｉａｎｄａＬｉＹａｎｄａ（ＤｅｐｔＡｕｔｏｍａｔｉｏｎ，ＴｓｉｎｇｈｕａＵｎｉｖｅｒｓｉｔｙ，Ｂｅｉｊｉｎｇ１０００８４）ＡｂｓｔｒａｃｔＣ...

关键词：盲道均衡数字通信码间干扰

Precise gradient separation of nanoparticles using reduced graphene oxide-polyoxomolybdate membranes

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Science China Chemistry 2025年第1期68卷 209-216页

作者： Yixin Yang Wanlei Zhao Ruoxuan Zheng Hongqiang li Wei Chen yu-Fei song State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology Quzhou Institute for Innovation in Resource Chemical Engineering

The purification and size sieving of nanoparticles （NPs） represents a significant scientific ***,the r GO-polyoxometalates (POMs=PMo12,Mo132and Mo368) membranes were fabricated successfully via a simple and scalable POMsassisted in-situ photoreduction *** the mass ratio of r GO to PMo12was 1:30,the resultant r GO-PMo12membranes with highly ordered and uniform nanochannels of 1.0 nm can be obtained,which showed an accurate carbon quantum dots（CQDs） separation with a cut-off size approximately 1.0 *** increase of the size of the interlayered POMs from PMo12（1.0 nm）,{Mo132}（2.9 nm） to{Mo368}（3.8 nm）,the resultant r GO-PMo12,r GO-Mo132and r GO-Mo368exhibited precise gradient separation of CQDs and Au nanoparticles by size exclusion *** results pave a promising way to construct new twodimensional （2D） membranes for highly efficient size-selective separation.

关键词： reduced graphene oxide polyoxometalates membranes gradient separation nanoparticles

Research and development of message service based on JMS

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通讯和计算机（中英文版） 2007年第5期4卷 47-51,61页

作者： song yu Wang li-li School of Computer Science and Technology North China Electric Power University Baodin 071003 China

Research on Substation Equipment Configuration Based on Object-Oriented Database

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通讯和计算机（中英文版） 2011年第8期8卷 615-618页

作者： yu song Dandan li School of Control and Computer Engineering North China Electric Power University Baoding 071003 China

Multilevel analysis of the central-peripheral-target organ pathway:contributing to recovery after peripheral nerve injury

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Neural Regeneration Research 2025年第10期20卷 2807-2822页

作者： Xizi song Ruixin li Xiaolei Chu Qi li Ruihua li Qingwen li Kai-yu Tong Xiaosong Gu Dong Ming Academy of Medical Engineering and Translational Medicine Tianjin UniversityTianjinChina Haihe Laboratory of Brain-Machine Interface and Human-Machine Fusion TianjinChina Department of Rehabilitation Tianjin University Tianjin HospitalTianjinChina Department of Hand Microsurgery Tianjin University Tianjin HospitalTianjinChina School of Exercise and Health Tianjin University of SportTianjinChina Department of Biomedical Engineering the Chinese University of Hong KongHong Kong Special Administrative RegionChina

Peripheral nerve injury is a common neurological condition that often leads to severe functional limitations and *** on the pathogenesis of peripheral nerve injury has focused on pathological changes at individual injury sites,neglecting multilevel pathological analysis of the overall nervous system and target *** has led to restrictions on current therapeutic *** this paper,we first summarize the potential mechanisms of peripheral nerve injury from a holistic perspective,covering the central nervous system,peripheral nervous system,and target *** peripheral nerve injury,the cortical plasticity of the brain is altered due to damage to and regeneration of peripheral nerves;changes such as neuronal apoptosis and axonal demyelination occur in the spinal *** nerve will undergo axonal regeneration,activation of Schwann cells,inflammatory response,and vascular system regeneration at the injury *** damage to target organs can occur,including skeletal muscle atrophy and sensory receptor *** then provide a brief review of the research advances in therapeutic approaches to peripheral nerve *** main current treatments are conducted passively and include physical factor rehabilitation,pharmacological treatments,cell-based therapies,and physical ***,most treatments only partially address the problem and cannot complete the systematic recovery of the entire central nervous system-peripheral nervous system-target organ ***,we should further explore multilevel treatment options that produce effective,long-lasting results,perhaps requiring a combination of passive(traditional)and active(novel)treatment methods to stimulate rehabilitation at the central-peripheral-target organ levels to achieve better functional recovery.

关键词： central nervous system central peripheral target organ multilevel pathological analysis nerve regeneration peripheral nerve injury peripheral nervous system target organs therapeutic approach