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Short Cycle Structure of Graphs on Surfaces (1)-the Uniqueness Theorems

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Acta Mathematicae Applicatae Sinica 2008年第4期24卷 677-680页

作者： Han Ren mo deng Department of Mathematics East China Normal University Shanghai 200062 China

In this paper we investigate cycle base structures of a （weighted） graph and show that much information of short cycles is contained in a MCB （minimum cycle base）. After setting up a Hall type theorem for base-transformation, we give a sufficient and necessary condition for a cycle base to be a MCB. Further more, we show that the structure of MCB in a （weighted） graph is unique. In the case of nonnegative weight, every pair of MCB have the same number of k-cycles for each integer k ≥ 3. The property is also true for those having longest length （although much work has been down in evaluating MCB, little is known for those having longest length）.

关键词： Cycle base facial cycle graph embedding

Learning to synthesize:robust phase retrieval at low photon counts

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Light(Science & Applications) 2020年第1期9卷 1657-1672页

作者： mo deng Shuai Li Alexandre Goy Iksung Kang George Barbastathis Department of Electrical Engineering and Computer Science Massachusetts Institute of TechnologyCambridgeMA 02139USA Sensebrain Technology Limited LLC 2550 N 1st StreetSuite 300San JoseCA 95131USA Omnisens SA Riond Bosson 31110 MorgesVDSwitzerland Department of Mechanical Engineering Massachusetts Institute of TechnologyCambridgeMA 02139USA Singapore-MIT Alliance for Research and Technology(SMART)Centre Singapore 117543Singapore

The quality of inverse problem solutions obtained through deep learning is limited by the nature of the priors learned from examples presented during the training *** in the case of quantitative phase retrieval,spatial frequencies that are underrepresented in the training database,most often at the high band,tend to be suppressed in the *** hoc solutions have been proposed,such as pre-amplifying the high spatial frequencies in the examples;however,while that strategy improves the resolution,it also leads to high-frequency artefacts,as well as low-frequency distortions in the ***,we present a new approach that learns separately how to handle the two frequency bands,low and high,and learns how to synthesize these two bands into full-band *** show that this“learning to synthesize”(LS)method yields phase reconstructions of high spatial resolution and without artefacts and that it is resilient to high-noise conditions,e.g.,in the case of very low photon *** addition to the problem of quantitative phase retrieval,the LS method is applicable,in principle,to any inverse problem where the forward operator treats different frequency bands unevenly,i.e.,is ill-posed.

关键词： synthesize bands phase

Synthesis of novel biodegradable poly(ethylene glycol) analogue:Water-soluble aliphatic polyester with pendant oligo(ethylene glycol) chains

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Chinese Chemical Letters 2009年第12期20卷 1502-1505页

作者： Lei Feng Jian Yuan Hao Cheng Dong Xiong Xian mo deng Chengdu Institute of Organic Chemistry Chinese Academy of Sciences P.O. Box 415 Chengdu 610041 China School of Microeletronics and Solid State Electronics University of Electronic Science and Technology of China Chengdu 610054 China Graduate School of Chinese Academy of Sciences Beijing 100039 China

A novel poly（ethylene glycol）（PEG） analogue composed of aliphatic polyester backbone and pendant oligo（ethylene glycol） short chains is reported. The PEG analogue is a copolymer synthesized by ring-opening alternating copolymerization of succinic anhydride with 2-（（2-（2-metho xyethoxy）ethoxy）methyl）oxirane. The structure of the copolymer was confirmed by ^1H NMR spectrum. The effects of the monomer feed ratio on the copolymerization were studied and the polymerization mechanism was given. The PEG analogue disclosed is water-soluble and expected to have promising applications in biomedical fields as a substitute of PEG due to the existence of degradable ester bond in the backbone.

关键词： Water-soluble PEG analogue 2-((2-(2-Methoxyethoxy)ethoxy)methyl)oxirane Ring-opening alternating copolymerization Polyester

Different crystallinity of poly(d,l-lactide-co-p-dioxanone) copolymers acquired by control of chain microstructure

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Chinese Chemical Letters 2009年第12期20卷 1506-1509页

作者： Hui Zhen Zhao Jian Yuan Hao Cheng Dong Xiong Xian mo deng Chengdu Institute of Organic Chemistry Chinese Academy of Sciences Chengdu 610041 China School of Microeletronics and Solid State Electronics University of Electronic Science and Technology of China Chengdu 610054 China Graduate School of Chinese Academy of Sciences Beijing 100039 China

Poly（d,l-lactide-co-p-dioxanone）（P（LA-co-PDO）） copolymers with different chain microstructures were synthesized by onestep or two-step bulk ring-opening polymerizations of d,l-lactide （LA） and p-dioxanone （PDO） monomers using stannous octoate [Sn（Oct）2]/n-dodecanol as the initiating system. The average sequence lengths of the lactidyl （LLA） and dioxanyl （LpDo） units were calculated from the ^1H NMR spectra. It was found that both LLA and Lpoo values from the two-step syntheses were significantly longer than those from the corresponding one-step syntheses, indicating more blocky structure achieved for the twostep copolymers. Corresponding to this difference in microstructure, the two-step copolymers were semi-crystalline, while the one-step copolymers were completely amorphous. In conclusion, the crystallinity of P（LA-co-PDO） copolymers could be adjusted conveniently to meet specific applications by changing the microstructure of the copolymers via different polymerization routes.

关键词： Poly(d,l-lactide-co-p-dioxanone) Copolymerization Chain microstructure Crystallinity

Nanoscale Pore Characteristics of the Upper Permian Mudrocks from a Transitional Environment in and around Eastern Sichuan Basin, China

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Acta Geologica Sinica(English Edition) 2019年第4期93卷 1025-1046页

作者： CAO Taotao LIU Guangxiang LIU Hu deng mo HAN Yuanhong HUANG Yanran Andrew S.HURSTHOUSE Hunan Provincial Key Laboratory of Shale Gas Resource Utilization Hunan University of Science and TechnologyXiangtanHunan 411201China Department of Geology Hunan University of Science and TechnologyXiangtanHunan 411201China Wuxi Research Institute of Petroleum Geology Petroleum Exploration and Production Research InstituteSINOPECWuxiJiangsu 214126China Sichuan Key Laboratory of Shale Gas Evaluation and Exploration Chengdu 600091China Key Laboratory of Coal Resources Exploration and Comprehensive Utilization Ministry of Land and ResourcesXi’an 710021China School of Science and Sport University of the West of ScotlandPaisley P A12BEUK

Nanoscale pore characteristics of the Upper Permian Longtan transitional mudrocks and their equivalent strata Wujiaping Formation marine mudrocks in and around the eastern Sichuan Basin was investigated using field emission scanning electron microscopy(FE-SEM)and low-pressure N2 adsorption *** results indicate that the Upper Permian mudrock is at a mature stage with total organic carbon(TOC)values ranging between 0.47%and 12.3%.The Longtan mudrocks mainly contain vitrinite,and their mineral composition is primarily *** contrast,the Wujiaping mudrocks are dominated by sapropelinite and solid bitumen,and their mineral compositions are mainly quartz and a notably high amount of *** FE-SEM reveals that clay mineral pores and microcracks are the common pore types in the Longtan *** specific surface area and pore volume depend on the clay content but are negatively correlated with the *** generation of nanometer pores in the Longtan mudrocks is caused by high clay mineral ***,the Wujiaping mudrock mainly contains OM pores,and the pore parameters are positively correlated with the *** OM pore development exhibits remarkable differences in the Longtan and Wujiaping mudrocks,which might be related to their sedimentary facies and maceral *** and inertinite appear as discrete particles in these mudrocks and cannot generate pores during thermal *** often contains many secondary pores,and solid bitumen with large particles,usually with several pores,is not the major contributor to the pore system of the investigated mudrock.

关键词： nanoscale pore characteristics FE-SEM low-pressure N2 adsorption transitional mudrock Longtan/Wujiaping Formation eastern Sichuan Basin

Research on Formation Mechanism and Forecast Method of Windows of Accumulated and Deeply Buried Shale Gas

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Acta Geologica Sinica(English Edition) 2015年第A01期89卷 233-234页

作者： BAO Yunjie ZHAI Changbo deng mo LV Junxiang Wuxi Research Institute of Petroleum Geology SINOPEC

1 Background The shale at the bottom of Wufeng-Longmaxi Formation is one of the major strata in exploration and exploitation of shales in southeast Sichuan. In the tectonic strong modified regions in the edge and outer places of the basin of southeast Sichuan, the Wufeng-Longmaxi Formation Shale lies in the favorable sedimentary facies of Deep Water-Shallow Water Shelf （Chen Zemin et al, 2013）, developing shale of rock facies with high silicon and high carbon which help the enrichment of shale gas and obtaining the material base for the shale gas to be accumulated into buried treasure.

关键词： SHALE gas GASES -- Absorption & adsorption ISOTHERMAL processes FORECASTING PREDICTION theory OIL fields

Short cycle structures for graphs on surfaces and an open problem of mohar and Thomassen

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Science China Mathematics 2006年第2期49卷 212-224页

作者： REN Han & deng mo Department of Mathematics, East China Normal University, Shanghai 200062, China College of Mathematics & Information Science, Northwest Normal University, Lanzhou 730070, China 1. Department of Mathematics East China Normal University Shanghai 200062 China 2. College of Mathematics & Information Science Northwest Normal University Lanzhou 730070 China

In this paper we investigate cycle base structures of a (weighted) graph and show that much information of short cycles is contained in an MCB (i.e., minimum cycle base). After setting up a Hall type theorem for base-transformation, we give a sufficient and necessary condition for a cycle base to be an MCB. Furthermore, we show that the structure of MCB in a (weighted)graph is unique. The property is also true for those having a longest length (although much work has been down in evaluating MCB, little is known for those having a longest length). We use those methods to find out some unknown properties for short cycles sharing particular properties in (unweighted) graphs. As applications, we determine the structures of short cycles in an embedded graph and show that there exist polynomially bounded algorithms in finding a shortest contractible cycle and a shortest two-sided cycle provided such cycles exist. Those answer an open problem of B. mohar and C. Thomassen.

关键词： cycle base facial cycle graph embedding.

Structures of Facial Cycles and C-bridges of Embedded Graphs with Locally LEW-embedding Properties

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Chinese Quarterly Journal of Mathematics 2008年第4期23卷 475-479页

作者： deng mo REN Han DONG Qian Department of Mathematics East China Normal University Shanghai 200062 China

In this paper, we show that for a locally LEW-embedded 3-connected graph G in orientable surface, the following results hold： 1） Each of such embeddings is minimum genus embedding; 2） The facial cycles are precisely the induced nonseparating cycles which implies the uniqueness of such embeddings; 3） Every overlap graph O（G, C） is a bipartite graph and G has only one C-bridge H such that C U H is nonplanar provided C is a contractible cycle shorter than every noncontractible cycle containing an edge of C. This extends the results of C Thomassen＇s work on LEW-embedded graphs.

关键词： (locally)LEW-embedding C-bridge overlap graph

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一种计算石油包裹体气液比的新方法

新疆石油地质 2016年第2期37卷 236-239页

作者：邓模中国石化石油勘探开发研究院无锡石油地质研究所江苏无锡214126

石油包裹体的气液比是热力学模拟的敏感性参数,应用石油包裹体热力学模拟方法可以获得古油气充注时的压力,通过石油包裹体二维平面分析和三维形态重构,可以获取石油包裹体的气液比。实例研究证明,在一定的石油包裹体形态范围内,通过二... 详细信息

石油包裹体的气液比是热力学模拟的敏感性参数,应用石油包裹体热力学模拟方法可以获得古油气充注时的压力,通过石油包裹体二维平面分析和三维形态重构,可以获取石油包裹体的气液比。实例研究证明,在一定的石油包裹体形态范围内,通过二维平面分析和三维形态重构获取的石油包裹体气液比与共聚焦激光-荧光扫描显微镜所测得的气液比的相对误差可以控制在±10%内。在缺少共聚焦激光-荧光扫描显微镜条件下,石油包裹体二维平面分析和三维形态重构方法比目估测量法能更准确地计算石油包裹体气液比,可以满足石油包裹体捕获压力模拟的精度要求。

关键词：石油包裹体气液比热力学模拟捕获压力