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Two new phenolic compounds from Ardisia gigantifolia

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Chinese Chemical Letters 2008年第6期19卷 693-695页

作者： Zhu Yang ping Wen nai Li Wang Xin Sheng Yao College of Traditional Chinese Materia Medica Shenyang Pharmaceutical University Shenyang 110016 China Shenzhen Key Laboratory for New Drugs Research of Traditional Chinese Medicines Research Institute of Tsinghua University Shenzhen 518057 China

Two new compounds were isolated from the 60% ethanol extract of the dried rhizome of Ardisia gigantifolia Stapf. The structures were elucidated on the basis of spectroscopic methods as （＋）-5-（1,2-dihydroxypentyl）... 详细信息

关键词： Ardisia gigantifolia Stapf Phenolic compounds 5-(1,2-Dihydroxypentyl)benzene-1,3-diol

Crystallization,Mechanical,Thermal and Rheological Properties of Polypropylene Composites Reinforced by Magnesium Oxysulfate Whisker

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Chinese Journal of Polymer Science 2017年第5期35卷 659-671页

作者： Li Dang Xue-ying nai Xin Liu Dong-hai Zhu Ya-ping Dong 李武 Key Laboratory of Salt Lake Resources Chemistry Qinghai Institute of Salt LakesChinese Academy of Sciences Key Laboratory of Comprehensive and Highly Efficient Utilization of Salt Lake Resources Qinghai Institute of Salt Lakes Chinese Academy of Sciences University of Chinese Academy of Sciences

Polypropylene （PP） composites containing magnesium oxysulfate whisker （MOSw） or lauric acid （LA） modified MOSw （LAMOSw） were prepared via melt mixing in a torque rheometer. The heterogeneous nucleating effect of LAMOSw was clearly observed in polarized light microscopy （PLM） pictures with the presence of an abundance of small spherulites. MOSw exhibited no nucleation effect and formed a few spherulites with large size. Compared with PP/MOSw composites, PP/LAMOSw exhibited better impact strength, tensile strength and nominal strain at break, ascribing to three possible reasons：（i） more β-crystal PP formed, （ii） better dispersity of LAMOSw in PP matrix and （iii） the plasticizing effect of LA. The results of dynamic mechanical thermal analysis （DMTA） indicated that brittleness of the PP matrix at low temperature was improved by the addition of LAMOSw, while the interracial interactions between MOSw and PP matrix were actually weakened by LA, as evidenced by the higher tan8 values over the entire range of test temperatures. In terms of the rheological properties of the composites, both the η＊ and G＇ at low frequencies increase with the addition of MOSw or LAMOSw, indicating that the PP matrix was transformed from liquid-like to solid-like. However, a network of whiskers did not form because no plateau was found in the G＇ at low frequencies. With low filler content, LAMOSw produced a stronger solid-like behavior than MOSw mainly due to the better dispersion of the LAMOSw in PP matrix. However, for highly-filled composites, the η＊ of PP/LAMOSw at low frequencies was smaller than that of PP/MOSw composite, since the particle- particle contact effect played a major role.

关键词： PP/MOSw composites Crystallization Thermal properties Mechanical properties Rheological properties

Some interesting properties of black hydrogen-treated TiO2 nanowires and their potential application in solar energy conversion

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Science China Chemistry 2015年第12期58卷 1810-1815页

作者： ping yu Jinzhong Zhang Department of Chemical Engineering Shenyang University of Chemical Technology Department of Chemistry and Biochemistry University of California

Hydrogen treatment has been proposed as a simple and effective strategy to enhance the performance of Ti O2 nanostructures for applications such as photocatalysis and photoelectrochemical(PEC) water splitting. While some studies have suggested that the black color can be ascribed to surface disorder, other reports have suggested that it is caused by the "oxygen vacancy" states associated with Ti3+ within the bandgap of the Ti O2. The chemical nature and potential use of the bandgap states responsible for the black color of increased visible absorption is not yet well understood and subject of strong interest. Here we briefly review current understanding of the possible mechanisms behind the black color of hydrogen-treated Ti O2 nanowires and its relevance to photocatalysis and solar water splitting for hydrogen generation. One important conclusion to date is that while hydrogen treatment enhances photocurrent of Ti O2 with UV excitation, no noticeable photocurrent can be detected with visible light, which seems to be due to the very short lifetimes of the bandgap oxygen vacancy states arising from hydrogen treatment.

关键词： black Ti O2 photoelectrochemical water splitting Ti O2 nanowires hydrogen treatment oxygen vacancy

Tracking Control for a Cushion Robot Based on Fuzzy Path Planning With Safe Angular Velocity

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IEEE/CAA Journal of Automatica Sinica 2017年第4期4卷 610-619页

作者： ping Sun Zhuang yu School of Information Science and Engineering Shenyang University of TechnologyShenyang 110870China

This study proposes a new nonlinear tracking control method with safe angular velocity constraints for a cushion robot. A fuzzy path planning algorithm is investigated and a realtime desired motion path of obstacle avoidance is obtained. The angular velocity is constrained by the controller, so the planned path guarantees the safety of users. According to Lyapunov theory, the controller is designed to maintain stability in terms of solutions of linear matrix inequalities and the controller's performance with safe angular velocity constraints is *** simulation and experiment results confirm the effectiveness of the proposed method and verify that the angular velocity of the cushion robot provided safe motion with obstacle avoidance.

关键词： Cushion robot path planning safe angular velocity tracking control

Global trends and hotspots of type 2 diabetes in children and adolescents:A bibliometric study and visualization analysis

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World Journal of Diabetes 2025年第1期16卷 140-168页

作者： Fang-Shuo Zhang Hai-Jing Li Xue yu Yi-ping Song Yan-Feng Ren Xuan-Zhu Qian Jia-Li Liu Wen-Xun Li Yi-Ran Huang Kuo Gao School of Acupuncture-Moxibustion and Tuina Beijing University of Chinese MedicineBeijing 100029China School of Traditional Chinese Medicine Beijing University of Chinese MedicineBeijing 100029China

BACKGROUND Epidemiological surveys indicate an increasing incidence of type 2 diabetes mellitus(T2DM)among children and adolescents *** to rapid disease progression,severe long-term cardiorenal complications,a lack of effective treatment strategies,and substantial socioeconomic burdens,it has become an urgent public health issue that requires management and *** T2DM differs from adult *** a significant increase in our understanding of youth-onset T2DM over the past two decades,the related review and evidence-based content remain *** To visualize the hotspots and trends in pediatric and adolescent T2DM research and to forecast their future research *** This study utilized the terms“children”,“adolescents”,and“type 2 diabetes”,retrieving relevant articles published between 1983 and 2023 from three citation databases within the Web of Science Core Collection(SCI,SSCI,ESCI).Utilizing CiteSpace and VoSviewer software,we analyze and visually represent the annual output of literature,countries involved,and participating *** allows us to predict trends in this research *** analysis encompasses co-cited authors,journal overlays,citation overlays,time-zone views,keyword analysis,and reference analysis,*** A total of 9210 articles were included,and the annual publication volume in this field showed a steady growth *** United States had the highest number of publications and the highest *** United States also had the most research institutions and the strongest research *** global hot journals were primarily diabetes professional journals but also included journals related to nutrition,endocrinology,and *** analysis showed that research related to endothelial dysfunction,exposure risk,cardiac metabolic risk,changes in gut microbiota,the impact on comorbidities and outcomes,etc.,were emerging *** have maintained their popularity in this field,sugges

关键词： Child Adolescent Type 2 diabetes mellitus Bibliometrics Knowledge mapping Visualization CiteSpace VOSviewer

Zn-air batteries for electric vehicles

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Tungsten 2024年第1期6卷 164-173页

作者： nai-Qi Meng yu-Xin Fan Jing-Sheng Cai State Key Laboratory of Molecular Engineering of Polymers Department of Macromolecular ScienceFudan UniversityShanghai 200438China College of Energy Soochow Institute for Energy and Materials InnovationS(SIEMIS)Key Laboratory of Advanced Carbon Materials and Wearable Energy Technologies of Jiangsu Province Soochow UniversitySuzhou 215006China Institute of New Energy for Vehicles School of Materials Science and EngineeringTongji UniversityShanghai 201804China

The increasingly serious environmental challenges have gradually aroused people's interest in electric *** the last decade,governments and automakers have collaborated on the manufacturing of electric vehicles with high ***-edge battery technologies are pivotal for the performance of electric ***-air batteries are considered as potential power batteries for electric vehicles due to their high ***-air battery researches can be classified into three categories:primary batteries,mechanically rechargeable batteries,and chemically rechargeable *** majority of current studies aim at developing and improving chemically rechargeable and mechanically rechargeable Zn-air *** have tried to use catalytic materials design and device design for Zn-air batteries to make it possible for their applications in electric *** review will highlight the state-of-the-art in primary batteries,mechanically rechargeable batteries,and chemically rechargeable batteries,revealing the prospects of Zn-air batteries for electric vehicles.

关键词： Energy storage Electric vehicles Bifunctional oxygen catalysts Mechanically rechargeable Zn-air batteries Chemically rechargeable Zn-air batteries

Syntheses, Structures, Electrochemistry and Magnetic Properties of Two Trinuclear Cyanide-bridged Clusters Based on Tricyanometalate Building Block

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Chinese Journal of Structural Chemistry 2019年第2期38卷 273-283,168页

作者： WANG An-ping DONG Da-Peng ZHAO Hai-Yan yu nai-Sen LI Zheng-Hua School of Physics and Materials Engineering Dalian Minzu University

The reaction of tricyanometallate precursor, Bu_4N[Fe(Tp)(CN)_3] and(Bu_4N)[(pzTp)Fe(CN)_3](Tp = tris(pyrazolyl)hydroborate, pzTp = tetrakis(pyrazolyl)borate) with Ni(ClO_4).26 H_2O in the presence of the monodentate N-methylimidazole ligand afforded two new cyano-bridged heterobimetallic {Fe2 Ni} trinuclear clusters, {[Fe(Tp)(CN)_3]_2[Ni(Mim)_4]}·8 H_2O(1) and {[Fe(pzTp)(CN)_3]_2[Ni(Mim)_4]}·2 CH_3OH·2H_2O(2). The molecular structure was determined by single-crystal X-ray diffraction. In the two compounds, the FeIII ions were coordinated by three cyanide carbon atoms and three nitrogen atoms of Tp(or pzTp) anions, whereas, the NiII ions were surrounded by two cyanide nitrogen atoms and four nitrogen atoms from four monodentate N-methylimidazole ligands, and they were bridged by tricyanometalate building block to form similar {Fe2Ni} trinuclear clusters. Cyclic voltammetry(CV) measurements indicated that compound 1 exhibited two quasireversible iron-centered reduction processes at –0.71 and –0.17 V and one quasireversible nickel-centered oxidation process at 0.92 V, while compound 2 showed two quasireversible iron-centered reduction processes at –0.66 and –0.09 V and one quasireversible nickel-centered oxidation process at 0.88 V. Magnetic measurements showed that compounds 1 and 2 exhibited strong intrachain ferromagnetic interaction between the low-spin Fe~Ⅲ(S = 1/2) and high-spin Ni~Ⅱ(S = 1) ions.

关键词： crystal structure cyanide ferromagnetic coupling nickel(Ⅱ)

Improved Information Set Decoding Algorithms over Galois Ring in the Lee Metric

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Journal of Systems Science & Complexity 2023年第3期36卷 1319-1335页

作者： LI yu WANG Li-ping State Key Laboratory of Information Security Institute of Information EngineeringChinese Academy of SciencesBeijing 100093China School of Cyber Security University of Chinese Academy of SciencesBeijing 100049China

The security of most code-based cryptosystems relies on the hardness of the syndrome decoding(SD) *** best solvers of the SD problem are known as information set,decoding(ISD) ***,Weger,et al.(2020) described Stern’s ISD algorithm,s-blocks algorithm and partial Gaussian elimination algorithms in the Lee metric over an integer residue ring Z_(pm),where p is a prime number and m is a positive integer,and analyzed the time *** this paper,the authors apply a binary ISD algorithm in the Hamming metric proposed by May,et al.(2011)to solve the SD problem over the Galois ring GR(p^(m),k) endowed with the Lee metric and provide a detailed complexity *** with Stern’s algorithm over Zpmin the Lee metric,the proposed algorithm has a significant improvement in the time complexity.

关键词： Galois ring information set decoding lee metric syndrome decoding

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Characteristics of inorganic phosphorus fractions and their correlations with soil properties in three non-acidic soils

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Journal of Integrative Agriculture 2022年第12期21卷 3626-3636页

作者： ZHANG nai-yu WANG Qiong ZHAN Xiao-ying WU Qi-hua HUANG Shao-min ZHU ping YANG Xue-yun ZHANG Shu-xiang Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences/National Engineering Laboratory for Improving Quality of Arable LandBeijing 100081P.R.China TERRA Gembloux Agro-Bio TechUniversity of LiegeGembloux 5030Belgium Institute of Environment and Sustainable Development in Agriculture Chinese Academy of Agricultural SciencesBeijing 100081P.R.China Institute of Bioengineering Guangdong Academy of Sciences/Guangdong Modern Agricultural Technology Research and Development CenterGuangzhou 510316P.R.China Institute of Plant Nutrient Agricultural Resources and Environmental SciencesHenan Academy of Agricultural SciencesZhengzhou 450002P.R.China Institute of Agricultural Resources and Environment Jilin Academy of Agricultural SciencesChangchun 130033P.R.China College of Natural Resources and Environment Northwest A&F UniversityYangling 712100P.R.China

Understanding the characteristics and influences of various factors on phosphorus(P)fractions is of significance for promoting the efficiency of soil *** on long-term experiments on black soil,fluvo-aquic soil,and loess soil,which belong to Phaeozems,Cambisols,and Anthrosols in the World Reference Base for Soil Resources(WRB),respectively,five fertilization practices were selected and divided into three groups:no P fertilizer(CK/NK),balanced fertilizer(NPK/NPKS),and manure plus mineral fertilizer(NPKM).Soil inorganic P(Pi)fractions and soil properties were analyzed to investigate the characteristics of the Pi fractions and the relationships between Pi fractions and various soil *** results showed that the proportion of Ca_(10)-P in the sum of total Pi fractions was the highest in the three soils,accounting for 33.5%in black soil,48.8%in fluvo-aquic soil,and 44.8%in loess ***-term fertilization practices resulted in periodic changes in soil Pi accumulation or *** black soil and fluvo-aquic soil,the Pi accumulation was higher in the late period(10–20 years)of fertilization than in the early period(0–10 years)under NPK/NPKS and NPKM,whereas the opposite result was found in loess *** Pi accumulation occurred in all Pi fractions in black soil;mainly in Ca_(8)-P,Fe-P,and Ca_(10)-P in fluvo-aquic soil;and in Ca_(2)-P,Ca_(8)-P,and O-P in loess *** CK/NK,the soil Pi was depleted mainly in the early period in each of the three *** addition to the labile Pi(Ca_(2)-P)and moderately labile Pi(Ca_(8)-P,Fe-P,Al-P),the Ca_(10)-P in black soil and fluvo-aquic soil and O-P in loess soil could also be used by *** analysis showed that soil properties explained more than 90%of the variation in the Pi fractions in each soil,and the explanatory percentages of soil organic matter(SOM)were 43.6%in black soil,74.6%in fluvo-aquic,and 38.2%in loess ***,decisions regarding the application of P fertilizer should consider

关键词： non-acidic soils long-term fertilization phosphorus fractions soil properties organic matter