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A Facile Synthesis of 3-Oxo-7αH-eudesma-4-ene-9β, 12-diol

2011 Chinese Control and Decision Conference（CCDC）

作者： gang chen and ming yu are with college of automation,chongqing university,chongqing 400044

The coordination and synchronization problems of networked passive systems with directed communication topologies are discussed in this *** with previous work in the context of passivity-based control,the development in this paper is for more general directed communication *** is shown that when the communication topologies are strongly connected,the output synchronization can be achieved for the networked passive *** realistic communication delays and actuator saturation are also *** achieved results are used to synchronize the networked Lagrangian *** examples are included to demonstrate the effectiveness of the proposed algorithms.

关键词： Synchronization Networked passive systems Distributed control

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Chinese Chemical Letters 1998年第7期9卷 625-627页

作者： Li Jun LIU Yong gang chen Zhao ming XIONG Jiang LI gang ZHOUand yu Lin Li(National Laboratory of Applied Organic Chemistry and Institute of Organic Chemistry, Lanzhou university, Lanzhou 730000)(Ningxia Medical college, Yinchuan 750001) Lanzhou Univ Natl Lab Appl Organ Chem Lanzhou 730000 Peoples R China Lanzhou Univ Inst Organ Chem Lanzhou 730000 Peoples R China Ningxia Med Coll Yinchuan 750001 Peoples R China

A facile ndxture of the C-11 isomeric 3 - oxo-7αH-eudes ma-4-en- 9β, 1 2-diol has been achieved ffom oxycarvone. The C-11 configuration of natural product is established through comparison of IHNMR spectra between ... 详细信息

关键词： Synthesis Sesquiterpenoid 3-oxo-7αH-eudesma-4-en-9β 12-diol oxycarvone

Intelligent geochemical interpretation of mass chromatograms:Based on convolution neural network

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Petroleum Science 2024年第2期21卷 752-764页

作者： Kai-ming Su Jun-gang Lu Jian yu Zi-Xing Lu Shi-Jia chen Hubei Key Laboratory of Petroleum Geochemistry and Environment Wuhan430100HubeiChina college of Resources and Environment Yangtze UniversityWuhan430100HubeiChina School of Geoscience and Technology Southwest Petroleum UniversityChengdu610500SichuanChina Changqing Oilfield Company PetroChinaXi'an710021ShaanxiChina

Gas chromatography-mass spectrometry(GC-MS)is an extremely important analytical technique that is widely used in organic *** is the only approach to capture biomarker features of organic matter and provides the key evidence for oil-source correlation and thermal maturity ***,the conventional way of processing and interpreting the mass chromatogram is both timeconsuming and labor-intensive,which increases the research cost and restrains extensive applications of this *** overcome this limitation,a correlation model is developed based on the convolution neural network(CNN)to link the mass chromatogram and biomarker features of samples from the Triassic Yanchang Formation,Ordos Basin,*** this way,the mass chromatogram can be automatically *** research first performs dimensionality reduction for 15 biomarker parameters via the factor analysis and then quantifies the biomarker features using two indexes(*** and PMI)that represent the organic matter thermal maturity and parent material type,***,training,interpretation,and validation are performed multiple times using different CNN models to optimize the model structure and hyper-parameter setting,with the mass chromatogram used as the input and the obtained MI and PMI values for supervision(label).The optimized model presents high accuracy in automatically interpreting the mass chromatogram,with R2values typically above 0.85 and0.80 for the thermal maturity and parent material interpretation results,*** significance of this research is twofold:(i)developing an efficient technique for geochemical research;(ii)more importantly,demonstrating the potential of artificial intelligence in organic geochemistry and providing vital references for future related studies.

关键词： Organic geochemistry Biomarker Mass chromatographic analysis Automated interpretation Convolution neural network Machine learning

Synthesis of (+)-5α-Hydroxy-β-selinene and (-)-5β-Hydroxy-β-selinene

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Chinese Chemical Letters 1998年第7期9卷 629-630页

作者： Zhao ming XIONG gang ZHOU Yong gang chen and yu Lin LI(National Laboratory of Applied organic Chemistry and Institute of Organic Chemistry,Lanzhou university, Lanzhou 730000) Lanzhou Univ Natl Lab Appl Organ Chem Lanzhou 730000 Peoples R China Lanzhou Univ Inst Organ Chem Lanzhou 730000 Peoples R China

A facile and efficient synthesis of (+)-5α-hydroxy -β-selinene 1 and (-)-5β-hydroxy-β-selinene 2 starting from (+)-dihydrocarvone 3 has been described.

关键词： Synthesis Sesquiterpenoid 5α-hydroxy-β-selinene 5β-hydroxy-β-selinene dihydrocarvone

A Facile Synthesis of 6β-Hydroxy-7α(H)-eudesma-4-en-3-one

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Chinese Chemical Letters 1998年第9期9卷 817-818页

作者： gang ZHOU Zhao ming XIONG Yong gang chen yu Lin LI (National Laboratory of Applied Organic Chemistry and Institute of Organic Chemistry,Lanzhou university, Lanzhou 730000) Lanzhou Univ Inst Organ Chem Lanzhou 730000 Peoples R China Lanzhou Univ Natl Lab Appl Organ Chem Lanzhou 730000 Peoples R China

A stereoselective total synthesis of 6β-hydroxy-7α(H)-eudesma-4-en-3- 1startingfrom (+)-dihydrocarvone 7 has been described.

关键词： synthesis sesquiterpene 6β-Hydroxy-7α(H)-eudesm-4-en-3-one sihydrocarvone

A Light-Weight Opportunistic Forwarding Protocol with Optimized Preamble Length for Low-Duty-Cycle Wireless Sensor Networks

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Journal of Computer Science & Technology 2017年第1期32卷 168-180页

作者： Hai-ming chen Li Cui gang Zhou Institute of Computing Technology Chinese Academy of Sciences Beijing 100190 China Department of Computer Science College of William and Mary Williamsburg VA 23185 U.S.A.

In wireless sensor networks, sensed information is expected to be reliably and timely delivered to a sink in an ad-hoc way. However, it is challenging to achieve this goal because of the highly dynamic topology induced from asynchronous duty cycles and temporally and spatially varying link quality among nodes. Currently some opportunistic forwarding protocols have been proposed to address the challenge. However, they involve complicated mechanisms to determine the best forwarder at each hop, which incurs heavy overheads for the resource-constrained nodes. In this paper, we propose a light-weight opportunistic forwarding （LWOF） scheme. Different from other recently proposed opportunistic forwarding schemes, LWOF employs neither historical network information nor a contention process to select a forwarder prior to data transmissions. It confines forwarding candidates to an optimized area, and takes advantage of the preamble in low-power-listening （LPL） MAC protocols and dual-channel communication to forward a packet to a unique downstream node towards the sink with a high probability, without making a forwarding decision prior to data transmission. Under LWOF, we optimize LPL MAC protocol to have a shortened preamble （LWMAC）, based on a theoretical analysis on the relationship among preamble length, delivery probability at each hop, node density and sleep duration. Simulation results show that LWOF, along with LWMAC, can achieve relatively good performance in terms of delivery reliability and latency, as a receiver-based opportunistic forwarding protocol, while reducing energy consumption per packet by at least twice.

关键词： wireless sensor network low duty cycle low power listening opportunistic forwarding

Immunological tolerance of human hepatocyte xenograft induced by adenovirus vector-mediated CTLA4Ig gene transfer

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Hepatobiliary & Pancreatic Diseases International 2012年第2期11卷 148-153页

作者： Yao-Kai chen,Xiao-Cong Liu,Jun-gang Li,Guo-Dong Liu,Yan Guo,Ling cheng and yu-ming Wang Institute of Infectious Diseases, Southwest Hospital, Third Military Medical university, chongqing 400038, China and Department of Digestive Diseases, General Hospital of chengdu Military Command, chengdu 610083, China [a] Institute of Infectious Diseases Southwest Hospital Third Military Medical University Chongqing 400038 China [b] Department of Digestive Diseases General Hospital of Chengdu Military Command Chengdu 610083 China

BACKGROUND:Systemic administration of CTLA4Ig has been applied in inducing immunological tolerance of hepatocyte implants,but has potential for systemic immune *** study was designed to induce hepatocyte immunological tolerance by locally expressing CTLA4Ig in an attempt to improve the effectiveness of cell ***:A normal human liver cell line(L02) was transfected with adenovirus vector containing the CTLA4Ig gene(Ad-CTLA4Ig-EGFP) in vitro,and the expression of CTLA4Ig by transfected cells was assessed by fluorescent imaging and immunocytochemical *** cells then were injected into the spleen of Sprague-Dawley rats,the survival of cells was determined by immunohistochemistry,and the immune status was examined through CD4 + and CD69 + T cellcounts and ELISA detection of IL-2 in peripheral ***:L02 cells expressed CTLA4Ig in the cytoplasm for >4 *** L02 cells were observed in the experimental group at 3 and 4 weeks post-transplantation,while none was detected in the control ***,the percentages of CD4 + and CD4 + CD69 + T cells in the CTLA4-transfected group were 24.5% and 45.1%,markedly lower than those in the control group at 4 weeks post-transplantation(P<0.01).Furthermore,the IL-2 level was also lower in the CTLA4transfected group than in the control ***:Adenovirus-mediated CTLA4Ig gene transfer into human hepatocytes has the potential to become an effective method of inducing immunological tolerance in hepatocyte transplantation.

关键词： CTLA4Ig adenovirus vectors hepatocyte transplantation immune tolerance graft rejection

First Total Synthesis of 4,5-Sccoeudesmane-type and Iphionane-type Compounds-Synthesis of 4,5-Dioxo-seco-γ-eudesmol and 5β,11-Dihydroxyiphionan-4-one

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Chinese Chemical Letters 2000年第2期11卷 113-114页

作者： Zhao ming XIONG gang ZHOU Xiao Lei GAO Yong gang chen yu lin LI (National Laboratory of Applied Organic Chemistry and Institute of organic Chemistry, Lanzhou university, Lanzhou 730000) Natl. Lab. of Appl. Organ. Chemistry Institute of Organic Chemistry Lanzhou University Lanzhou 730000 China

4, 5-Secoeudesmane-type and iphionane-type compounds are sesquiterpenes with new carbon skeletons found in natrual sources in recent years.1-6 The co-occurence of 4, 5-secoeudesmanes, iphionanes and eudesmanes as natrual products suggests that 4, 5-secoeudesmanes, iphionanes most likely are generated biogenetically from eudesmanes, and iphionanes are formed biogenetically by aldol reaction of 4, 5-dioxosecoeudesmanes1,4,6,7. The study on the synthesis of this two kind of new sesquiterpenes has not been reported in the literature.

关键词： type First Total Synthesis of 4,5-Sccoeudesmane-type and Iphionane-type Compounds-Synthesis of 4,5-Dioxo-seco eudesmol and 5 Dihydroxyiphionan-4-one

Advances of machining techniques for gradient structures in multi-principal-element alloys

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Rare Metals 2022年第12期41卷 4015-4026页

作者： Bo Li Chun-ming Niu Tian-Long Zhang Gong-yu chen gang Zhang Dong Wang Xiao-Ye Zhou Jia-ming Zhu School of Civil Engineering Shandong UniversityJinan 250061China School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China Department of Materials Science and Engineering College of Science and EngineeringHong Kong Institute for Advanced StudyCity University of Hong KongHong Kong 999077China School of Physics and Optoelectronics Technology Baoji University of Arts and SciencesBaoji 721016China Center of Microstructure Science Frontier Institute of Science and TechnologyXi'an Jiaotong UniversityXi’an 710049China Guangdong Province Key Laboratory of Durability for Marine Civil Engineering School of Civil and Transportation EngineeringShenzhen UniversityShenzhen 518060China

Multi-principal-element alloys(MPEAs)are attracting increasing attentions because of their high strength and ductility,high fracture toughness,excellent corrosion resistance,outstanding thermal-softening resistance and high oxidation ***,gradient structures(GSs)have been shown to be effective in alleviating the strength-ductility trade-off although strength and ductility are mutually exclusive properties for metals,which provides an opportunity for developing highperformance ***,we summarized four processing methods for creating GSs in MPEAs,including rotationally accelerated shot peening(RASP),ultra-precision machining technology(UPMT),cyclic dynamic torsion(CDT),and ultrasonic surface rolling processing(USRP).Principles,advantages,disadvantages,and typical applications of these methods are discussed in this work.

关键词： Gradient structures(GSs) Multi-principalelement alloys(MPEAs) Strength-ductility trade-off Advanced processing technology