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现代化工 2013年第1期33卷 1-4页

作者：杨挺孙小涛中国化工经济技术发展中心北京100723

页岩气作为一种重要的非常规天然气,已成为全球油气资源勘探开发的新热点。笔者从页岩气概况、资源储量、生产现状、技术进展、开发成本等多方面探讨了页岩气开发的技术可行性和经济性,并提出了页岩气开发在水资源消耗和环境污染等方面... 详细信息

页岩气作为一种重要的非常规天然气,已成为全球油气资源勘探开发的新热点。笔者从页岩气概况、资源储量、生产现状、技术进展、开发成本等多方面探讨了页岩气开发的技术可行性和经济性,并提出了页岩气开发在水资源消耗和环境污染等方面存在的问题。

关键词：页岩气储量生产现状技术进展成本环境保护

Effects of e-e Interaction on the CDW of MX Complex

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Chinese Physics Letters 1994年第2期11卷 105-108页

作者： YU Zhigang sun Xin Department of Physics Fudan UniversityShanghai 200433

We have considered the effects of Hubbard repulsion on the charge-density-wave(CDW)state of halogen-bridged mixed-valence transition metal complex(MX complex)within mean field theory(MFT),and taken electron correlation into account by second-order perturbation relative to the mean field *** is seen correlation reduces the dimerization and narrows the band gap further compared with MFT.

关键词： state. narrow perturbation

Robust observer-driven switching stabilization of switched linear systems

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控制理论与应用（英文版） 2013年第1期11卷 69-73页

作者： Jun WU Zhendong sun College of Automation Science and Engineering South China University of Technology

In this work, we study the robust observer-driven switching stabilization problem of switched linear sys- tems. Under the condition that each subsystem is completely observable, with the observer-driven switching law which makes the system exponentially stable for the nominal system, we prove that the overall system is robust against structural/switching perturbations and is input/output to state stable for unstructural perturbations.

关键词： Switched linear systems Observer-driven switching stabilization Robustness

Fluorescent Linear Supramolecular Polymer Based on Host-Guest Interactions

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Chinese Journal of Chemistry 2017年第11期35卷 1669-1672页

作者： Chenxiao Xiong Ruyi sun School of Chemistry and Molecular Engineering East China Normal University Shanghai 200241 China

Construction of supramolecular polymers, in which functional monomer components are held together by non- covalent interactions, is considered as a promising design principle for functional materials. Linear fluorescent su- pramolecular polymer assembled on account of electrostatic attractions based host-guest interaction is synthesized and illustrated here. 1H NMR was involved to ensure the structure of guest and polymer, UV-vis and fluorescent spectra were recorded to be a readout signal to investigate the assemble process of polymer. TEM and AFM meas- urements were carried out to confirm the homogeneous nanometer-sized molecular assembly. It shows the way to be used as remote readout fluorescent functional material in the future.

关键词： supramolecular polymer stimuli responsive molecular machines functional material

Study of High Capacitance Ratios CPW MEMS Shunt Switches

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稀有金属材料与工程 2006年第A03期35卷 548-549页

作者： Jianhai sun Dafu Cui State Key Lab. of Transducer Tech. Institute of Electronics Chinese Academy of Sciences Beijing 100080 China

This paper describes a fixed-fixed beam ohmic switch in series with a fixed capacitor as a replacement for a capacitive *** this switch,a metal plate deposited on the dielectric ensures perfectly contact with the dielectric layer in the down *** area size of the metal plate directly influences the capacitance ratio of the switch,as the area size of the metal cap decreases,the capacitance ratio dramatically rises *** down/up capacitance ratio can exceed 800 times over the conventional designs using the same materials and the equal *** results show that high capacitance ratio of the switches has a large effect on the isolation,and can actually improve the performance of the switches.

关键词： capacitive shunt switch capacitance ratio isolation insertion loss

To be the best in marine sciences

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Journal of Oceanology and Limnology 2020年第4期38卷 897-905页

作者： sun Song WANG Fan Institute of Oceanology Chinese Academy of SciencesQingdao 266071China

Every institute in the world has its own history,culture,and legacy that show its unique *** an oldest,largest,and one of the most advanced institute in marine sciences in China,the Institute of Oceanology,Chinese Academy of Sciences(IOCAS)was established by her founders in 1950 and cherished by her successors ever *** has undertaken her own development roadmap over the last seventy *** people know its history,achievements,and contributions in marine sciences,but few would know the stories behind the *** paper intends to reveal the driven factors pushing the institute forward in the past,present,and future.

关键词： mariculture ocean health deep sea Institute of Oceanology,Chinese Academy of Sciences(IOCAS)

Digital computation of linear canonical transform for local spectra with flexible resolution ability

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Science China(Information Sciences) 2019年第4期62卷 206-208页

作者： Yannan sun Bingzhao LI School of Mathematics and Statistics Beijing Institute of Technology Beijing Key Laboratory on MCAACI Beijing Institute of Technology

Dear editor,The linear canonical transform(LCT) is a threeparameter linear integral transform [1]. It has many applications in optical systems, filter design, image watermarking, and other fields [2, 3].Moreover, the ... 详细信息

关键词： LCT flexible Digital computation of linear canonical transform for local spectra with flexible resolution ability

Designing future farmed fishes using genome editing

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Science China(Life Sciences) 2019年第3期62卷 420-422页

作者： yonghua sun Zuoyan Zhu State Key Laboratory of Freshwater Ecology and Biotechnology Institute of Hydrobiology The Innovative Academy of Seed Design Chinese Academy of Sciences College of Advanced Agricultural Sciences University of Chinese Academy of Sciences

Aquaculture,the most rapidly growing food production sector,has exhibited tremendous expansion over the past several decades and it currently accounts for more than half of the global fish production for human *** ensure sustainable aquaculture,it is necessary to breed farmed fish species(strains)with valuable economic traits,such as high production,high quality,disease resistance,and stress *** fish genetic breeding techniques largely rely on key processes including understanding the genetic basis of economically important traits to the generation and selection of favorable genotypes.

关键词： Designing future farmed fishes genome editing

Total Synthesis of Antitumor constituent Howiinol A

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Chinese Chemical Letters 1997年第4期8卷 293-294页

作者： sun, SY Yu, DQ CHINESE ACAD MED SCI INST MAT MEDBEIJING 100050PEOPLES R CHINA BEIJING UNION MED COLL BEIJING 100050PEOPLES R CHINA

Howiinol A, an active antitumor constituent from the root and stem bark of Goniothamus howii Meer. (Annoaceae) has been synthesized in nine steps from alpha - D - glucoheptonic gamma - lactone with an overall yield of... 详细信息

关键词： THF Total Synthesis of Antitumor constituent Howiinol A

Genetic lineage tracing identifies adaptive mechanisms of pancreatic islet β cells in various mouse models of diabetes with distinct age of initiation

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Science China(Life Sciences) 2024年第3期67卷 504-517页

作者： Qi Fu Yu Qian Hemin Jiang Yunqiang He Hao Dai Yang Chen Zhiqing Xia Yucheng Liang Yuncai Zhou Rui Gao Shuai Zheng Hui Lv Min sun Kuanfeng Xu tao Yang Department of Endocrinology the First Affiliated Hospital of Nanjing Medical UniversityNanjing 210029China

During the pathogenesis of type 1 diabetes(T1D) and type 2 diabetes(T2D), pancreatic islets, especially the β cells, face significant challenges. These insulin-producing cells adopt a regeneration strategy to compensate for the shortage of insulin, but the exact mechanism needs to be defined. High-fat diet(HFD) and streptozotocin(STZ) treatment are well-established models to study islet damage in T2D and T1D respectively. Therefore, we applied these two diabetic mouse models, triggered at different ages, to pursue the cell fate transition of isletβ cells. Cre-LoxP systems were used to generate islet cell type-specific(α, β, or δ) green fluorescent protein(GFP)-labeled mice for genetic lineage tracing, thereinto β-cell GFP-labeled mice were tamoxifen induced. Single-cell RNA sequencing(scRNA-seq) was used to investigate the evolutionary trajectories and molecular mechanisms of the GFP-labeled β cells in STZ-treated mice. STZ-induced diabetes caused extensive dedifferentiation of β cells and some of which transdifferentiated into α or δ cells in both youth-and adulthood-initiated mice while this phenomenon was barely observed in HFD models. β cells in HFD mice were expanded via self-replication rather than via transdifferentiation from α or δ cells, in contrast, α or δ cells were induced to transdifferentiate into β cells in STZ-treated mice(both youthand adulthood-initiated). In addition to the re-dedifferentiation of β cells, it is also highly likely that these “α or δ” cells transdifferentiated from pre-existing β cells could also re-trans-differentiate into insulin-producing β cells and be beneficial to islet recovery. The analysis of ScRNA-seq revealed that several pathways including mitochondrial function, chromatin modification, and remodeling are crucial in the dynamic transition of β cells. Our findings shed light on how islet β cells overcome the deficit of insulin and the molecular mechanism of islet recovery in T1D and T2D pathogenesis.

关键词： islet regeneration lineage tracing high fat diet(HFD) streptozotocin(STZ)