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Ionic liquid catalyzed solvent-free synthesis of chalcone and its derivatives under mild conditions

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Chinese Journal of Chemical Engineering 2021年第5期34卷 160-166页

作者： Qiu Zhao Gang Wang Fuxia liao Yifan sha Fei Xu Chunshan li Zengxi li Yijun cao School of Chemical Engineering and Energy Zhengzhou UniversityZhengzhou 450001China Key Laboratory of Green Process and Engineering State Key Laboratory of Multiphase Complex SystemsBeijing Key Laboratory of Ionic Liquids Clean ProcessInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China School of Chemical Sciences University of Chinese Academy of SciencesBeijing 100049China

An ionic liquid(IL)catalyzed solvent-free process was developed for the direct synthesis of chalcone and its derivatives by using substituted acetophenones and benzaldehydes via aldol reaction under mild conditions.A series of acidic and basic ILs were selected and *** influences of cations and reaction conditions on product yield and selectivity were systematically ***[Bmim]OH was identified as the optimal IL,with the highest yield and selectivity reaching up to 96.7% and 100%,respectively.A reaction mechanism-based kinetic model was established and regressed with experimental data,revealing the β-Hydroxylketone dehydrolysis with activation barrier of 37.8 kJ·mol^(-1) was observed as the ratecontrolling step.

关键词： Ionic liquid Chalcone Aldol reaction Kinetic model

Near infrared emissions from both high efficient quantum cutting (173%) and nearly-pure-color upconversion in NaY(WO_(4))_(2):Er^(3+)/Yb^(3+) with thermal management capability for silicon-based solar cells

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light(Science & Applications) 2024年第1期13卷 113-126页

作者： Duan Gao Baojiu chen Xuezhu sha Yuhang Zhang Xin chen li Wang Xizhen Zhang Jinsu Zhang Yongze cao Yichao Wang Lei li Xiangping li Sai Xu Hongquan Yu lihong cheng School of Science Dalian Maritime UniversityDalian 116026 LiaoningChina

Raising photoelectric conversion efficiency and enhancing heat management are two critical concerns for siliconbased solar *** this work,efficient Yb^(3+) infrared emissions from both quantum cutting and upconversion were demonstrated by adjusting Er^(3+) and Yb^(3+) concentrations,and thermo-manage-applicable temperature sensing based on the luminescence intensity ratio of two super-low thermal quenching levels was discovered in an Er^(3+)/Yb^(3+) codoped tungstate *** quantum cutting mechanism was clearly decrypted as a two-step energy transfer process from Er^(3+) to Yb^(3+).The two-step energy transfer efficiencies,the radiative and nonradiative transition rates of all interested 4 f levels of Er^(3+) in NaY(WO_(4))_(2) were confirmed in the framework of Föster-Dexter theory,Judd-Ofelt theory,and energy gap law,and based on these obtained efficiencies and rates the quantum cutting efficiency was furthermore determined to be as high as 173%in NaY(WO_(4))_(2):5 mol%Er^(3+)/50 mol%Yb^(3+) *** and nearly pure infrared upconversion emission of Yb3+under 1550 nm excitation was achieved in Er^(3+)/Yb^(3+)co-doped NaY(WO_(4))_(2) by adjusting Yb^(3+) doping *** Yb^(3+) induced infrared upconversion emission enhancement was attributed to the efficient energy transfer ^(4)I_(11/2)(Er^(3+))+^(2)F_(7/2)(Yb^(3+))→^(4)I_(15/2)(Er^(3+))+^(2)F_(5/2)(Yb^(3+))and large nonradiative relaxation rate of ^(4)I_(9/2).Analysis on the temperature sensing indicated that the NaY(WO_(4))_(2):Er^(3+)/Yb^(3+)serves well the solar cells as thermos-managing ***,it was confirmed that the fluorescence thermal quenching of ^(2)H_(11/2)/^(4)S_(3/2) was caused by the nonradiative relaxation of ^(4)S_(3/2).All the obtained results suggest that NaY(WO_(4))_(2):Er^(3+)/Yb^(3+) is an excellent material for silicon-based solar cells to improve photoelectric conversion efficiency and thermal management.

关键词： quantum thermal relaxation

Comparative Analysis of Polysaccharides from Two Ecological Types of Leymus chinensis

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Chemical Research in Chinese Universities 2012年第4期28卷 677-681页

作者： li Jing-jing BI Hong-tao YAN Jl-hong SUN Fang FAN sha-sha cao Gang ZHOU Yi-fa chen Xi-guang College of Marine life Science Ocean University of China Qingdao 266003 P. R. China Key Laboratory of Adaptation and Evolution of Plateau Biota Northwest Institute of Plateau Biology Chinese Academy of Sciences Xining 810008 P. R. China Bee Research Institute Chinese Academy of Agricultural Sciences Beo'ing 100093 P. R. China School of life Sciences Northeast Normal University Changchun 130024 P. R. China

Leymus chinensis（Trin.） Tzvel.,widely distributed at eastern Eurasian steppe and divided into gray-green type and yellow-green type,has different stress resistance to *** the present study,the water-soluble polysaccharides from two ecotypes of *** were analyzed in detail,and the differences between polysaccharides from the two ecotypes of *** in the yield,monosaccharide composition,molecular weight and structure were *** polysaccharides of *** were composed of both neutral and acidic *** neutral polysaccharides contained mannose,glucose,galactose,xylose and arabinose,and mainly consisted of β-1,4-Glcp,α-1,3-Galp and α-1,2-Xylp *** acidic polysaccharides contained mannose,rhamnose,glucuronic acid,galacturonic acid,glucose,galactose,xylose and ***,the yields,monosaccharides contents and the molecular weights of the polysaccharides from the two ecotypes of *** were ***,the resistance type（gray-green type） of *** contained a number of α-1,3-Manp and reducing end of β-Glcp residues,and much more O-methyl groups than normal type（yellow-green type） of *** differences of the polysaccharides of the two ecotypes of *** might be due to the long-term environmental adaptability of plant,and the differences of the polysaccharides might influence the stress resistance of ***.

关键词： Leymus chinensis Polysaccharide Fractionation

DNA vaccines targeting amyloid-βoligomer ameliorate cognitive deficits of aged APP/PS1/tau triple-transgenic mouse models of Alzheimer’s disease

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Neural Regeneration Research 2022年第10期17卷 2305-2310页

作者： sha sha Xiao-Na Xing Tao Wang Ying li Rong-Wei Zhang Xue-li Shen Yun-Peng cao Le Qu Department of Geriatrics the First Affiliated Hospital of China Medical UniversityShenyangLiaoning ProvinceChina Department of Neurology Shenzhen Luohu People’s HospitalThe Third Affiliated Hospital of Shenzhen UniversityShenzhenGuangdong ProvinceChina College of life and Health Sciences Northeastern UniversityShenyangLiaoning ProvinceChina Department of Neurology the First Affiliated Hospital of China Medical UniversityShenyangLiaoning ProvinceChina Department of Dermatology the First Affiliated Hospital of China Medical UniversityShenyangLiaoning ProvinceChina

The amyloid-β(Aβ)oligomer,rather than the Aβmonomer,is considered to be the primary initiator of Alzheimer’s *** was hypothesized that p(Aβ3-10)10-MT,the recombinant Aβ3-10 gene vaccine of the Aβoligomer has the potential to treat Alzheimer’s *** this study,we intramuscularly injected the p(Aβ3-10)10-MT vaccine into the left hindlimb of APP/PS1/tau triple-transgenic mice,which are a model for Alzheimer’s *** results showed that the p(Aβ3-10)10-MT vaccine effectively reduced Aβoligomer levels and plaque deposition in the cerebral cortex and hippocampus,decreased the levels tau protein variants,reduced synaptic loss,protected synaptic function,reduced neuron loss,and ameliorated memory impairment without causing any cerebral ***,this novel DNA vaccine,which is safe and highly effective in mouse models of Alzheimer’s disease,holds a lot of promise for the treatment of Alzheimer’s disease in humans.

关键词： Aβoligomers cognitive dysfunction DNA vaccine immunotherapy neuron loss plaque deposits synaptic function tau hyperphosphorylation

Parallel decline of CD8+CD38+ lymphocytes and viremia in treated hepatitis B patients

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World Journal of Gastroenterology 2011年第17期17卷 2191-2198页

作者： Wei cao Zhi-Feng qiu Tai-sheng li Department of Infectious Diseases Peking Union Medical College Hospital Peking Union Medical College Chinese Academy of Medical Sciences Beijing 100730 China

AIM:To assess the peripheral T lymphocyte subsets in chronic hepatitis B virus(HBV) infection,and their dynamics in response to adefovir dipivoxil ***:Proportions and absolute counts of peripheral natural killer cells,B cells,CD8+,CD4+,CD8+ CD38+,CD8+CD28+ and CD4+CD28+ T cells were determined using three-color flow cytometry in chronic hepatitis B patients(n = 35),HBV carriers(n = 25) and healthy controls(n = 35).Adefovir dipivoxil was initiated in 17 chronic hepatitis B patients who were regularly followed for 72 wk,during which period the T cell subsets and serum viral load were measured at each follow-up ***:The peripheral CD4+ T cell counts and CD8+ T cell counts decreased in chronic HBV *** chronic hepatitis B patients,proportions of CD8+CD38+ T cells were 62.0% ± 14.7%,much higher than those of HBV carriers and healthy *** the 13 hepatitis B patients who were treated and responded to adefovir dipivoxil,proportions of CD8+CD38+ T cells decreased from 53.9% ± 18.4% pre-therapy to 20.1% ± 11.3% by week 72(P line(HBV DNA fell from 7.31 to 3 log copies/mL).CD8+ T cell counts also underwent an average increase of 218 cells/μL by the end of 72-wk *** those who failed the therapy,the CD8+CD38+ T cell population had more ***:CD8+ T cells abnormally activated in chronic HBV infection can be partially reversed by antiviral ***-associated immune activation may be a crucial part of the pathogenesis and a promising target of treatment.

关键词： Hepatitis B virus Chronic hepatitis B CD8+CD38+ T cell subsets

Photo-induced morphology transition of a multifunctional photochromic bisthienylethene molecule with switchable aggregation-induced emission

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Science China Chemistry 2018年第10期61卷 1301-1306页

作者： sheng Wang Fang Wang chengpeng li Teng li Derong cao Xiang Ma Key Laboratory of Applied Chemistry and School of Chemistry and Chemical Engineering Development Center for New Materials Engineering & Technology in Universities of Guangdong Lingnan Normal University School of Chemistry and Chemical Engineering State Key Laboratory of Luminescent Materials and DevicesSouth China University of Technology Key Laboratory for Advanced Materials and Institute of Fine Chemicals School of Chemistry and Molecular EngineeringEast China University of Science & Technology

A novel multifunctional molecule BTE-CNPH was designed and synthesized by connecting 2-(3′,5′-bis(trifluoromethyl)-biphenyl-4-yl)-2-cyanovinyl group to both side of the bisthienylethene(BTE), which exhibited excellent aggregation-induced emission(AIE) and bistable photochromism. High-contrast(>60) reversible fluorescence switching was achieved in the 1 D nanowires, solid of BTE-CNPH and also in a polymethyl methacrylate(PMMA) film loaded with 1% BTE-CNPH under the alternative irradiation by 365 nm and visible light. Interestingly, the nanowire-like assembly morphology of BTE-CNPH in aqueous tetrahydrofuran(THF) solution of specific concentration was observed to translate into amorphous pieces gradually upon prolonged irradiation by the 365 nm, accompanying with photo-tunable AIE emission.

关键词： photochromism bisthienylethene aggregation-induced emission

MG63 Osteoblast-like Cells Growth Behaviour on Carbon/Carbon Composites with Different Carbon Matrixes

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Chinese Journal of Mechanical Engineering 2011年第2期24卷 303-308页

作者： ZHANG Leilei li Hejun li Kezhi ZHAO Xueni WU Heng cao sheng State Key Laboratory of Solidification Processing Northwestern Polytechnical University Xi ＇an 710072 China

During the process that implant materials are used for bone replacement,the cell responses to implant materials determine the long-term stability of bone *** microstructure of implant materials is considered as a critical factor that influences the cell ***/Carbon composites（C/C composites） are novel implant materials,but there are few reports on the effect of their microstructure,especially the carbon matrixes and holes,on cell *** this paper,C/C composites with different carbon matrixes are prepared by chemical vapor infiltration and pressure impregnation carbonization technique,*** structure of holes is *** cell responses to C/C composites with different carbon matrixes are evaluated with MG63 osteoblast-like *** morphologies of MG63 osteoblast-like cells on the surface of C/C composites,especially in the holes are assessed by scanning electron microscope,and cell proliferation behavior is evaluated by 3-[4,5-dimethylthiozol-2-yl]-2,5-diphenyltetrazolium bromide（MTT） assay. The results show that MG63 osteoblast-like cells have a lamellar morphology with similar sizes and spreading areas as well as the same proliferation behaviors for C/C composites with different carbon *** matrix shows unapparent influence on the cell growth ***,MG63 osteoblast-like cells have various interactions with the holes of C/C *** cells stride over the holes with 6～8μm in size,and connect with each other or grow along the curvature wall of the holes with a size of 30-40μm;the cells present three-dimensional morphologies inside the holes and display circular shapes along the ridge of the *** cell-material interactions are found according to the size and position of the holes,which provides theoretical foundation for the microstructure design of clinical C/C composites.

关键词： Carbon/Carbon composite matrix osteoblast growth behavior microstructure

Geometry of Motion for Video shakiness Detection

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Journal of Computer Science & Technology 2018年第3期33卷 475-486页

作者： Xiao-Qun Wu Hai-sheng li Jian cao Qiang Cai School of Computer and Information Engineering Beijing Technology and Business University Beijing 100048 China Beijing Key Laboratory of Big Data Technology for Food Safety Beijing Technology and Business University Beijing 100048 China

This paper presents a novel algorithm for automatically detecting global shakiness in casual videos. Per-frame amplitude is computed by the geometry of motion, based on the kinematic model defined by inter-frame geometric transformations. Inspired by motion perception, we investigate the just-noticeable amplitude of shaky motion perceived by the human visual system. Then, we use the thresholding contrast strategy on the statistics of per-frame amplitudes to determine the occurrence of perceived shakiness. For testing the detection accuracy, a dataset of video clips is constructed with manual shakiness label as the ground truth. The experiments demonstrate that our algorithm can obtain good detection accuracy that is in concordance with subjective judgement on the videos in the dataset.

关键词： video shakiness kinematic model motion perception

Characteristics of Permafrost along Highway G214 in the Eastern Qinghai-Tibet Plateau

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Journal of Mountain Science 2015年第5期12卷 1135-1144页

作者： sheng Yu cao Yuan-bing li Jing WU Ji-chun chen Ji FENG Zi-liang State Key Laboratory of Frozen Soil Engineering Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences

The characteristics of the permafrost along National Highway No. 214(G214) in Qinghai province(between kilometer markers K310 and K670),including the distribution patterns of permafrost and seasonally frozen ground(SFG), ground ice content and mean annual ground temperature(MAGT), were analyzed using a large quantity of drilling and measured ground temperature data. Three topographic units can be distinguished along the highway: the northern mountains, including Ela Mountain and Longstone Mountain; the medial alluvial plain and the southern Bayan Har *** horizontal distribution patterns of permafrost can be divided into four sections, from north to south: the northern continuous permafrost zone(K310-K460),the island permafrost zone(K460-K560), the southern continuous permafrost zone(K560-K630),and the discontinuous permafrost zone(K630-K670).Vertically, the permafrost lower limits(PLLs) of the discontinuous zone were 4200/4325 m, 4230/4350 m,and 4350/4450 m on the north-facing/south-facing slopes of Ela Mountain, Longstone Mountain and Bayan Har Mountains, respectively. The permafrost was generally warm, with MAGTs between-1.0°C and0°C in the northern continuous permafrost zone,approximately-0.5°C in the island permafrost zone,between-1.5°C and 0°C in the southern continuous permafrost zone, and higher than-0.5°C in the discontinuous permafrost zone. In contrast, the spatial variations in ground ice content were mainly controlled by the local soil water content and *** relationships between the mean annual air temperature(MAAT) and the PLLs indicated that the PLLs varied between-3.3°C and-4.1°C for the northern Ela and Longstone Mountains and between-4.1°C and-4.6°C in the southern Bayan Har Mountains.

关键词： Permafrost characteristics NationalHighway No. 214 (G214) Eastern Qinghai-TibetPlateau Qinghai-Tibet Plateau Temperature