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Chinese Chemical Letters 2010年第8期21卷 931-934页

作者： hong sheng li yi qun li Department of Chemistry Jinan UniversityGuangzhou 510632China

In the presence of diethyl 1,4-dihydro-2,6-dimethylpyridine-3,5-dicarboxylate（DHP） and a catalytic amount of potassium iodide,severalα-halo ketones were easily reduced to the corresponding ketones in acetone *** procedure presented here showed several merits such as short reaction time,practical experimental and isolated procedure,and excellent yields of products.

关键词： Dehalogenation α-Halo ketones Hantzsch ester 1 4-Dihydro-2 6-dimethylpyridine-3 5-dicarboxylate Potassium iodide

Optimal investment with transaction costs based on exponential utility function:a parabolic double obstacle problem

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Applied Mathematics(A Journal of Chinese Universities) 2011年第4期26卷 483-492页

作者： BAO qun-fang YANG Jing-yang SUN Chao li sheng-hong Department of Mathematics Zhejiang University Hangzhou 310027 China Jingdezhen Ceramic Institute Jiangxi 333403 China

This paper concerns optimal investment problem with proportional transaction costs and finite time horizon based on exponential utility function. Using a partial differential equation approach, we reveal that the problem is equivalent to a parabolic double obstacle problem involving two free boundaries that correspond to the optimal buying and selling policies. Numerical examples are obtained by the binomial method.

关键词： Optimal investment transaction costs double obstacle problem stochastic control exponential utility function.

A Generalized Semi-Holographic Universe

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Chinese Physics Letters 2013年第8期30卷 220-224页

作者： li Hui ZHANG hong-sheng ZHANG yi Department of Physics Yantai University30 Qingquan RoadYantai 264005 Shanghai United Center for Astrophysics(SUCA) Shanghai Normal University100 Guilin RoadShanghai 200234 College of Mathematics and Physics Chongqing University of Posts and TelecommunicationsChongqing 400065 State Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190 High Energy Physics Division Argonne National LaboratoryLemontIL 60439USA

We study the semi-holographic idea in the context of decaying dark *** energy flow between dark energy and the compensating dark matter is thermodynamically generalized to involve a particle number variable dark component with non-zero chemical *** is found that,unlike the original semi-holographic model,no cosmological constant is needed for a dynamical evolution of the universe.A transient phantom phase appears while a non-trivial dark energy-dark matter scaling solution stays at a later time,which evades the big-rip and helps to resolve the coincidence *** reasonable parameters,the deceleration parameter is well consistent with current *** original semi-holographic model is extended and it also suggests that the concordance model may be reconstructed from the semi-holographic idea.

关键词： potential problem holographic

Modeling study on the flow patterns of gas–liquid flow for fast decarburization during the RH process

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International Journal of Minerals,Metallurgy and Materials 2018年第2期25卷 153-163页

作者： yi-hong li Yan-ping Bao Rui Wang li-feng Ma Jian-sheng liu Collaborative Innovation Centre of Taiyuan Heavy Machinery Equipment and School of Materials Science and Engineering Taiyuan University of Science and Technology State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing School of Materials Science and Engineering North University of China

A water model and a high-speed video camera were utilized in the 300-t RH equipment to study the effect of steel flow patterns in a vacuum chamber on fast decarburization and a superior flow-pattern map was obtained during the practical RH process. There are three flow patterns with different bubbling characteristics and steel surface states in the vacuum chamber： boiling pattern（BP）, transition pattern（TP）, and wave pattern（WP）. The effect of the liquid-steel level and the residence time of the steel in the chamber on flow patterns and decarburization reaction were investigated, respectively. The liquid-steel level significantly affected the flow-pattern transition from BP to WP, and the residence time and reaction area were crucial to evaluate the whole decarburization process rather than the circulation flow rate and mixing time. A superior flow-pattern map during the practical RH process showed that the steel flow pattern changed from BP to TP quickly, and then remained as TP until the end of decarburization.

关键词： modeling study flow pattern vacuum chamber residence time decarburization RH process

Hydrothermal-sedimentary dolomite—A case from the Middle Permian in eastern Junggar Basin,China

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Journal of Palaeogeography 2020年第4期9卷 415-437页

作者： Shuai Zhang yi-qun liu hong li Xin Jiao Ding-Wu Zhou State Key Laboratory of Continental Dynamics Northwest UniversityXi'an 710069Shaanxi ProvinceChina Department of Geology Northwest UniversityXi'an 710069Shaanxi ProvinceChina Key Laboratory of Alpine Ecology Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

The Middle Permian Lucaogou Formation in the Jimusar Sag,eastern Junggar Basin,NW China,was deposited in a salt lake within an intracontinental rift basin with intense hydrothermal ***-sedimentary dolomite in the form of three types of dolostones,namely,analcime-feldspar dolostone(AFD),silicic dolostone(SD)and buddingtonite-albite dolostone(BAD),related to syn-sedimentary hydrothermal activity at lake bottom was *** characteristics and formation mechanism of the dolomite were studied based on micron-scale petrographic and isotopic geochemical *** syn-depositional formation of these dolostones was indicated by their rock-mineral features and syn-sedimentary deformation *** dolomite was composed of relatively poorly ordered proto-dolomite crystals with micron-sized spherical or sub-spherical morphology and coexisted with hydrothermal minerals,including analcime,buddingtonite,albite and *** clasts were replaced by the dolomite,indicating high-temperature conditions during *** remarkably low strontium isotopic compositions of the dolostones(87Sr/86Sr with an average of 0.705687)indicated that mantle-derived materials might have involved in the ore-forming *** dolostones had positiveδ13CPDB values(with an average of 6.94‰)and negativeδ18OPDB values(with an average of-8.12‰).Based on theδ18OPDB values,the formation temperatures of the dolomite were at least^25ºC higher than those of the penecontemporaneous dolomite in the Lucaogou Formation in the study *** is concluded that the dolomite precipitated from hydrothermal fluid erupting at the lake *** possible genetic models are *** suggest that the hydrothermal-sedimentary dolomite is an important genetic type,and this study may help increase the awareness of this understudied type of dolomite.

关键词： Dolomite genesis Hydrothermal sedimentary dolomite Permian Lucaogou Formation Jimusar Sag Junggar Basin

A translational study of somatosensory evoked potential time–frequency components in rats,goats,and humans

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Neural Regeneration Research 2021年第11期16卷 2269-2275页

作者： hong-Yan Cui yi-Xin Wu Rong li Guang-sheng li Yong Hu Institute of Biomedical Engineering Chinese Academy of Medical Sciences and Peking Union Medical CollegeTianjinChina Department of Orthopaedics and Traumatology The University of Hong KongHong Kong Special Administrative RegionChina Spinal Division Department of OrthopaedicsAffiliated Hospital of Guangdong Medical UniversityGuangdong ProvinceChina Department of Orthopaedics and Traumatology The University of Hong Kong-Shenzhen HospitalShenzhenGuangdong ProvinceChina

Somatosensory evoked potentials(SEPs)have been widely used to assess neurological function in clinical practice.A good understanding of the association between SEP signals and neurological function is helpful for precise diagnosis of impairment *** studies on SEPs have been reported in animal ***,few studies have reported the relationships between SEP waveforms in animals and those in *** this study,we collected normal SEP waveforms and decomposed them into specific time–frequency components(TFCs).Our results showed three stable TFC distribution regions in intact goats and rats and in *** we induced spinal cord injury in the animal models,a greater number of small TFC distribution regions were observed in the injured goat and rat groups than in the normal ***,there were significant correlations(Plinear relationships between the main SEP TFCs of the human group and those of the goat and rat groups.A stable TFC distribution of SEP components was observed in the human,goat and rat groups,and the TFC distribution modes were similar between the three *** in various animal models in this study could be translated to future clinical studies based on SEP TFC *** studies were approved by the Institutional Review Board of the University of hong Kong/Hospital Authority hong Kong West Cluster(approval *** 05-312 T/975)on December 5,*** experiments were approved by the Committee on the Use of live Animals in Teaching and Research of li Ka Shing Faculty of Medicine of the University of hong Kong(approval *** 2912-12)on January 28,*** experiments were approved by the Animal Ethics Committee of Affiliated Hospital of Guangdong Medical University(approval ***2002132)on March 5,2018.

关键词： animal models chronic compression latency somatosensory evoked potentials spinal cord injury time-frequency analysis time-frequency components translational study

Values of endoscopic ultrasonography for diagnosis and treatment of duodenal protruding lesions

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2008年第4期9卷 329-334页

作者： Guo-qiang XU yi-qun WU li-jun WANG hong-tan CHEN Department of Gastroenterology the First Affiliated Hospital School of Medicine Zhejiang University Hangzhou 310003 China Department of Pathology the First Affiliated Hospital School of Medicine Zhejiang University Hangzhou 310003 China

Objective： The diagnoses of patients with duodenal protruding lesions are difficult when using conventional examinations such as computed tomography （CT） and conventional endoscope etc. Thus, we investigated the clinical value of endoscopic ultrasonography （PUS） with miniature ultrasonic probes on the diagnosis and treatment of duodenal protruding lesions. Methods： Patients with duodenal protruding lesions who were indicated for PUS were examined by PUS with 12-15 MHz miniature ultrasonic probes and double-cavity electronic endoscope. According to diagnosis of PUS, those patients were indicated for biopsy and treatment received biopsy, endoscopic resection or surgical excision. The postoperative histological results were compared with the preoperative diagnosis of PUS. Those patients without endoscopic resection or surgical excision were periodically followed up with PUS. Results： A total of 169 patients with duodenal protruding lesions were examined by PUS, of which 40 were diagnosed with cysts, 36 with inflammatory protruding or polyp, 25 with Brunner＇s gland adenoma, 19 with ectopic pancreas, 17 with gastrointestinal stromal tumor, 12 with extrinsic compression, 12 with minor papilla, 6 with lipoma, 1 with adenocarcinoma and 1 with lymphoma. After PUS examinations, 75 patients received biopsy, endoscopic resection or surgical excision respectively. The postoperative histological results of 70 patients were completely consistent with the preoperative diagnosis of PUS, with 93.33% diagnostic accuracy. The results of follow-up with PUS indicated that duodenal cyst, Brunner＇s gland adenoma, ectopic pancreas, gastrointestinal stromal tumor and lipoma remained unchanged within 1-3 years. No related complications occurred among all patients that received PUS examinations. Conclusion： PUS is an effective and reliable diagnostic method for duodenal protruding lesions.

关键词： Endoscopic ultrasonography (EUS) Duodenal protruding lesions Diagnosis Follow-up

Modulating ion current rectification generating high energy output in a single glass conical nanopore channel by concentration gradient

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Chinese Chemical Letters 2015年第1期26卷 43-46页

作者： li-Xiang Zhang Yu-Bin Zheng sheng-lin Cai Xiao-hong Cao Yao-qun li Department of Chemistry and the MOE Key Laboratory of Spectrochemical Analysis & Instrumentation College of Chemistry and Chemical Engineering.Xiamen University Shenzhen Haibin Pharmaceutical Co. Ltd.

Inspired by biological systems that have the inherent skill to generate considerable bioelectricity from the salt content in fluids with highly selective ion channels and pumps on cell membranes, herein, a fully abiotic, single glass conical nanopores energy-harvesting is demonstrated. Ion current rectification （ICR） in negatively charged glass conical nanopores is shown to be controlled by the electrolyte concentration gradient depending on the direction of ion diffusion. The degree of ICR is enhanced with the increasing forward concentration difference. An unusual rectification inversion is observed when the concentration gradient is reversely applied. The maximum power output with the individual nanopore approaches 10^4pW. This facile and cost-efficient energy-harvesting system has the potential to power tiny biomedical devices or construct future clean-energy recovery plants.

关键词： Glass conical nanopore channe Ion current rectification Concentration gradient Energy generation

Synthesis and evaluation of nitrate derivatives of colchicine as anticancer agents

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Chinese Chemical Letters 2011年第7期22卷 768-770页

作者： li hong Shen Ya li Da Hai Zhang yi sheng Lai li Jie liu Department of Chemistry Handan College Handan 056005 China Center of Drug Discover China Pharmaceutical University Nanjing 210009 China Hebei yiling Medicine Corporation Ltd. Shijiazhuang 050035 China

To search for more potent antitumor agent, a series of novel nitric oxide-donating colchicine （Col） derivatives （6a-f, 8a and b） were synthesized by coupling nitrates with N-methyl colchiceinamide. Their cytotoxicity against four human cancer cell lines in vitro were evaluated by MTT assay. It was found that many of the derivatives displayed significant activity, particularly, compounds 6c, 8a and 8b showed more potent cytotoxic activities than Col.

关键词： Colchicine N-methyl colchiceinamide Nitrates Cytotoxicity

Synthesis and Properties of Dinuclear Europium(Ⅲ)Complex Containing 2-Benzoylbenzoic Acid

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Chinese Journal of Structural Chemistry 2022年第3期41卷 248-252,I0014页

作者： YANG ying-qun li Chang-hong li Wei YANG Tian-yi Key Laboratory of Functional Metal-organic Compounds of Hunan Province&Key Laboratory of Functional Organometallic Materials of Hunan Province College Hengyang 421008China Department of Chemistry and Materials Science Hengyang Normal UniversityHengyang 421008China School of Materials and Chemical Engineering Hunan Institute of TechnologyHengyang 421002China

A new europium(Ⅲ)complex[Eu2(C_(14)H_(9)O_(3))_(6)(2,2'-bipy)2]·(2,2'-bipy)_(2)has been synthesized with 2-benzoylbenzoic acid and 2,2'-bipyridine as *** data:triclinic,space group P1,with a=13.5251(5),b=13.9453(5),c=15.3582(5)Å,α=76.922(3)º,β=79.740(3)º,γ=64.248(4)º,V=2530.83(18)Å3,Dc=1.496 g/cm3,Z=1,μ(MoKα)=1.305 mm-1,F(000)=1156,the final R=0.0340 and wR=*** Eu(Ⅲ)ion is coordinated by eight atoms to give a distorted square antiprism coordination *** complex exhibits antiferromagnetism in the temperature range of 300~2 K,and two intense fluorescence emission bands arising from the transitions of Eu^(3+):^(5)D_(0)→^(7)F_(1)(595 nm)and^(5)D_(0)→^(7)F_(2)(618 nm),*** addition,the fluorescence sensing properties of the complex in CrO_(4)^(2-)solution were studied.

关键词： europium(Ⅲ)complex crystal structure magnetic and fluorescent properties