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Installing hydrogen bonds as a general strategy to control viscosity sensitivity of molecular rotor fluorophores Special Collection:Aggregation-Induced Processes and Functions

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Aggregate 2024年第1期5卷 367-376页

作者： Baoxing Shen Lihua Liu Yubo Huang Jichun Wu Huan Feng Yu Liu He Huang Xin Zhang Department of Chemistry Research Center for Industries of the FutureWestlake UniversityHangzhouChina Westlake Laboratory of Life Sciences and Biomedicine HangzhouChina School of Food Science and Pharmaceutical Engineering Nanjing Normal UniversityNanjingChina CAS Key Laboratory of Separation Science for Analytical Chemistry Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalianChina

Molecular rotor-based fluorophores(RBFs)activate fluorescence upon increase of micro-viscosity,thus bearing a broad application promise in many fields.However,it remains a challenge to control how fluorescence of RBFs responds to viscosity changes.Herein,we demonstrate that the formation and regulation of intramolecular hydrogen bonds in the excited state of RBFs could modulate their rotational barrier,leading to a rational control of how their fluorescence can be activated by micro-viscosity.Based on this strategy,a series of RBFs were developed based on 4-hydroxybenzylidene-imidazolinone(HBI)that span a wide range of viscosity sensitivity.Combined with the AggTag method that we previously reported,the varying viscosity sensitivity and emission spectra of these probes enabled a dualcolor imaging strategy that detects both protein oligomers and aggregates during the multistep aggregation process of proteins in live cells.In summary,our work indicates that installing intracellular excited state hydrogen bonds to RBFs allows for a rational control of rotational barrier,thus allow for a fine tune of their viscosity sensitivity.Beyond RBFs,we envision similar strategies can be applied to control the fluorogenic behavior of a large group of fluorophores whose emission is dependent on excited state rotational motion,including aggregation-induced emission fluorophores.

关键词： fluorescent probe intramolecular hydrogen bond protein aggregation rotor-based fluorophores viscosity sensitivity

Physical and Chemical Properties of Horns Sheaths Particles for the Manufacture of Composite Materials

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Journal of Materials Science and Chemical Engineering 2024年第5期12卷 1-9页

作者： Tawe Laynde Zakari Yaou Karga Tapsia Lionel Konai Noel Danwe Raidandi Department of Wood Construction University Institute for Wood Technology University of Yaounde 1 Yaounde Cameroon Department of Industrial and Mechanical Engineering National Advance School of Engineering University of Yaounde 1 Yaounde Cameroon Department of Mechanical Petroleum and Gas Engineering National Advance School of Mines and Petroleum Industries University of Maroua Maroua Cameroon

Salvaged cow horns from slaughterhouses have been transformed into fine particles for a physical characterization that has led us to determine the humidity rate (2.34% ± 0.054%), the actual density situated between 0.586 g/cm3 and 0.732 g/cm3, the swelling rate (12%), and one chemical characterization that permitted us to determine the rate of dry matters (97.05%), of mineral matters (2.5%), of protein matters (94.52%). From these weak values, it can easily be seen that cow horn case doesn’t absorb much water and improve the mechanical characteristics of the composite;the high rate of protein shows that keratin which is the structural molecule favors its gripping as reinforcing element in the manufacturing of composite materials.

关键词： Horns Fibers Polymer Loads Physical Properties Chemical Composition

Physicochemical and Thermal Properties of Some Key Tropical Sawdust Woods for Energy Production

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Journal of Sustainable Bioenergy Systems 2024年第1期14卷 1-22页

作者： Davy Fiwa Kaoke Yann Le Brech Emmanuel Talla Anthony Dufour Patrick Mountapmbeme Kouotou Department of Chemical Engineering School of Chemical Engineering and Mineral Industries University of Ngaoundere Ngaoundere Cameroon National Advanced School of Engineering of Maroua University of Maroua Maroua Cameroon Laboratory of Reactions and Process Engineering University of Lorraine-France Nancy France Higher Institute of Agriculture Wood Water and Environment University of Ebolowa Ebolowa Cameroon

In South Saharan countries, 85% of the population uses biomass as a primary energy source. Cameroon presents one of the highest biomass energy and sawmills produce important sawdust resources which are not used and are burnt in piles leading to significant air toxic emissions. Therefore, we have to valorize industrially these available sawdusts. This study focuses on the physicochemical and thermochemical analysis of Ayous, Sapelli and Tali sawdust. The proximate and ultimate analysis, particle size, structural composition, as well as heavy metal content and calorific value were determined. In addition, the thermogravimetric mass losses were also estimated. The results showed that high water contents (24% - 41%) were recorded in the raw sawdust, and the thermal treatment reduced these contents from 78% to values in the range of 4% - 9%. The values for ash and volatile matter content were respectively between 0.25% - 0.74% and 68% - 76%. The LHV is higher in Ayous (17.5 MJ/kg) and Sapelli (16.8 MJ/kg) than that of Tali (15.7 MJ/kg). The concentration of heavy metals is very low in each species. Extractives are more present in Tali (16.06%) than in the other sawdusts. Pyrolysis of sawdust shows the typical decomposition of hemicellulose (270˚C - 325˚C), cellulose (325˚C - 400˚C) and lignin (200˚C - 550˚C) with a maximum loss of 75% at 370˚C and the melting point is 320˚C. The results of the sawdust parameters determined in the paper can be valorized to reduce pollutants emissions by developing the efficiency and effectiveness of biomass energy processes and promoting the use of biomass as a sustainable alternative to traditional fossil fuels.

关键词： Wood Sawmills Sawdust Combustion Energy

MULTIAXIAL CREEP-FATIGUE LIFE EVALUATION UNDER PROPORTIONAL LOADING

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Acta Metallurgica Sinica(English Letters) 2004年第4期17卷 355-360页

作者： Y.Noguchi M.Miyahara Corporate Research & Development Laboratories Sumitomo Metal Industries Ltd. Amagasaki Hyogo 660-0891 JapanCorporate Research & Development Laboratories Sumitomo Metal Industries Ltd. Amagasaki Hyogo 660-0891 Japan

A new method was proposed for the multiaxial creep-fatigue life evaluation under proportional loadings. Because this method was derived from the strain range partitioning method with a multiaxiality factor, it was possible to consider the influence of both creep-fatigue interaction and multiaxial stress state on fatigue life. In order to predict the combined axial-torsional fatigue life the damage under combined loading was defined as linear summation of the damages under axial loading and torsional loading. Axial-torsional creep-fatigue tests were carried out using tubular specimens of 316LC austenitic stainless steel and the ferritic rotor steel. This rotor steel was developed for the permanent magnet type eddy current retarder in heavy trucks. Experimentally obtained lives of both steels were well corresponded with the lives predicted by the proposed method. It was found that the proposed method was effective in multiaxial fatigue life evaluation under proportional creep-fatigue loadings.

关键词： multiaxial fatigue creep-fatigue proportional loading life evaluation

Influence of Production Factors on the Physico-Chemical Characteristics of Fermented Cassava Dough and Sensory Evaluation of Attieke

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Food and Nutrition Sciences 2024年第5期15卷 361-376页

作者： Weiléko Hélène Dougba Djedjro Clément Akmel Emmanuel Aya Diane Boudouin Dibi Nogbou Emmanuel Assidjo Laboratory of Industrial Processes for Environmental Synthesis and New Energies Institut National Polytechnique F&#233lix Yamoussoukro C&#244te d&#8217Ivoire Department of Agro-Food and Food industries UFR Agriculture Fisheries Resources and Agro-Industry University of San-Pedro San-Pedro C&#244te d&#8217Ivoire

Attieke is an Ivorian semolina which obtained by fermenting, pressing and steaming cassava dough. Attieke production remains a traditional activity carried out by less literate women. However, perceived differences in measurable factors and attieke qualities require an investigation of their influence on the characteristics of the pressed dough and attieke. The aim of this study is to improve the quality of the dough in relation to that of the attieke produced. The experiment was carried out on 4 production factors, namely the type of boiled or braised ferment, the incorporation rate of the ferment between 8 and 10%, the addition of oil from 0.1 to 1% and the fermentation time from 12 to 15 hours applied to the Improved African Cassava (IAC) variety. A complete experiment design of 16 samples of fermented dough and attieke was employed. These samples underwent physic-chemical analyses for the fermented dough and sensory evaluation for the attieke. It was found that, except for titratable acidity, reducing sugar content and ash content, the physico-chemical characteristics of the dough of IAC variety were significantly influenced by all production factors and their interaction. Fermentation time significantly influences 60% of the physico-chemical characteristics of the fermented dough. The type of ferment, the oil addition and the ferment rate have a significant influence at 40% of these characteristics. At the sensory level, color, acidity and grain binding with an explained variance of 34.60% were essential for the appreciation of the attieke samples. Thus, these production factors could be considered for the improvement of the fermented dough and attieke production process.

关键词： Influence Production Fermented Dough Attieke

Metallaphotoredox-Catalyzed Three-Component Couplings for Practical Synthesis of Ureas and Carbamates

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Chinese Journal of Chemistry 2024年第3期42卷 264-270页

作者： Ernest Koranteng Zhen-Cao Shu Yi-Yin Liu Qian Yang Bin Shi Qiang-Xian Wu Fen Tan Liang-Qiu Lu Wen-Jing Xiao Engineering Research Center of Photoenergy Utilization for Pollution Control and Carbon Reduction Ministry of EducationCollege of ChemistryCentral China Normal University152 Luoyu RoadWuhanHubei430079 China Wuhan Youji industries Co. LtdNo.1 2nd Chemical Rd.WuhanHubei430082 China Hubei Key Laboratory of Purification and Application of Plant Anti-cancer Active Ingredients School of Chemistry and Life SciencesHubei University of EducationWuhanHubei430205 China State Key Laboratory for Oxo Synthesis and Selective Oxidation Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhouGansu730000 China School of Chemistry and Chemical Engineering Henan Normal UniversityXinxiangHenan453007 China Wuhan Institute of Photochemistry and Technology WuhanHubei430082 China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai200032 China

Ureas are widely used in drugs,materials and catalysts because of their diamide structure,which can form strong hydrogen bonds.Therefore,it is of great scientific significance to develop efficient and green methods for the synthesis of urea compounds,especially unsymmetrical ureas.Here,we have disclosed novel and highly efficient three-component coupling reactions of organic halides,sodium cyanate and amines enabled by nickel/photoredox dual catalysis for the preparation of unsymmetrical ureas.The reaction features simple and safe operations,broad substrate scopes,and product diversities.It allows the facile synthesis of N-aryl/vinyl ureas from readily available,user-friendly feedstocks under mild conditions(27 examples,36%—98%yields).In addition,this method is further derived to alcohols as nucleophiles to synthesize a series of carbamates(15 examples,40%—95%yields).The mechanism experiment shows that the isocyanate produced by the coupling of halide and sodium cyanate may be the key intermediate in this reaction.

关键词： Cross-coupling Nickel Photoredox catalysis Three-component reaction Ureas Carbamates

Compact Hybrid Subsystem of 16 Channel Optical Demultiplexer, 2x2 Switches, Optical Power Monitors and Control Circuit

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光学学报 2003年第S1期23卷 259-260页

作者： Kenichiro Takahashi Toshihiko Kishimoto Shintaro Mouri Youichi Hata Hideaki Yusa Mitsuaki Tamura Kazuhito Saito Hisao Maki sumitomo Electric industries Ltd. 1 Taya Sakae Yokohama JapanSumitomo Electric Industries Ltd. 1 Taya Sakae Yokohama JapanSumitomo Electric Industries Ltd. 1 Taya Sakae Yokohama JapanSumitomo Electric Industries Ltd. 1 Taya Sakae Yokohama JapanSumitomo Electric Industries Ltd. 1 Taya Sakae Yokohama JapanSumitomo Electric Industries Ltd. 1 Taya Sakae Yokohama JapanSumitomo Electric Industries Ltd. 1 Taya Sakae Yokohama JapanSumitomo Electric Industries Ltd. 1 Taya Sakae Yokohama Japan

A compact hybrid subsystem of 16channel optical demultiplexer, 2x2 switches, optical power monitors and control circuit board is developed. The subsystem is able to add or drop arbitrary optical channels and monitor t... 详细信息

关键词： of on in have Switches Compact Hybrid Subsystem of 16 Channel Optical Demultiplexer Optical Power Monitors and Control Circuit

Safety Control of a Class of Fully Actuated Systems Subject to Uncertain Actuation Dynamics

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Journal of Systems Science & Complexity 2022年第2期35卷 543-558页

作者： WU Si LIU Tengfei State Key Laboratory of Synthetical Automation for Process industries Northeastern UniversityShenyang 110004China

Safety is an essential requirement for control systems.Typically,controlled mobile robots are subject to safety constraints,to which control laws in typical forms may not be directly applicable.This paper employs barrier function to describe safety constraints,analyzes the interaction between the barrier function and the uncertain actuation dynamics by employing the ideas of interconnected systems,and proposes a quadratic-programming-based integration of the control algorithms subject to the safety constraint for a class of fully actuated systems.

关键词： Dynamic uncertainties fully-actuated systems safety control

Shaping global health promotion:a comprehensive analysis of the 10 Global Conferences on Health Promotion Conferences(1986-2021)Author links open overlay panel

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Global Health Journal 2024年第2期8卷 91-96页

作者： Shiyu Liu Meichen Sun Na Zhang Zhaozhang Sun Xiangyang Tian Liming Li Youfa Wang Global Health Institute School of Public HealthXi'an Jiaotong UniversityXi'anShaanxiChina School of Nursing Health Science CenterXi'an Jiaotong UniversityXi'anShaanxiChina Department of Culture Media and Creative IndustriesKing's College LondonLondonUnited Kingdom Chinese Center for Health Education BeijingChina School of Public Health Peking UniversityBeijingChina

Objective This study analyzed how the 10 Global Conferences on Health Promotion have played a significant role in shaping and promoting a worldwide consensus and actions on health promotion,effectively addressing diverse health challenges that evolved over different periods.Methods The textual analysis method was used in this study and text encoding was conducted to systematically examine the declarations and reports presented by the 10 Global Conferences on Health Promotion held during 1986-2021.We summarized the themes and key achievements,and key vocabulary in the conference declarations was extracted and analyzed to construct the global health promotion consensus and actions.Results The fundamental principles of the conferences are to foster consensus and initiate actions in the realm of health promotion on a global scale.The primary purpose and goal are to promote health from regional to global.Significantly,our findings highlight a transition in the primary actors driving health promotion.It underscores a shift in health promotion from being driven primarily by organizations like the World Health Organization,governments,and international bodies,to a more inclusive approach involving non-governmental organizations and the general public.This development implies that health promotion has evolved into a collective global endeavor,demanding the proactive involvement of various stakeholders,and forging new alliances in public health.Meanwhile,the coronavirus disease 2019(COVID-19)pandemic has further shaped the landscape of health promotion,underscoring the need for intensified focus on areas including disease prevention,health education,and the integration of digital health technologies,and emphasizing the importance of a multidimensional,responsive approach in public health initiatives.Conclusions Sustained collaboration and innovative strategies are pivotal to advancing health promotion globally.Countries,together with public and private entities,should intensify cooperation.Multisectoral collaboration among

关键词： Global conference on health promotion Health promotion Consensus and actions