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Palladium-Catalyzed One-Step Synthesis of Stereodefined Difunctionalized Glycals

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CCS Chemistry 2023年第3期5卷 741-749页

作者： Xiao-Ping Gong Yuke Li Hong-Chao Liu Zhe Zhang Zhi-Jie Niu Ya-Nan Ding Yang An Xi Chen Yan-Chong Huang rui-qiang jiao Xue-Yuan Liu Yong-Min Liang State Key Laboratory of Applied Organic Chemistry Lanzhou UniversityLanzhou 730000 Department of Chemistry Centre for Scientific Modeling and ComputationChinese University of Hong KongShatinHong Kong 999077

Efficiently modifying glycals by directly introducing functional groups into their double bonds is a longstanding ***,the strategy of introducing two different functional groups into 1-iodoglycals to obtain modified glycals in one step through palladium catalysis was reported for the first time,and the modified glycals contained stereodefined tetrasubstituted *** this method,various difunctionalized glycals that were difficult to form by other routes were synthesized in moderate to good *** experiments and density functional theory calculations show that the palladium catalyst played dual roles in this transformation,namely,inducing nucleophilic substitution and catalyzing Suzuki *** reaction intermediate was isolated and confirmed by X-ray crystallographic ***,the gram-scale synthesis and facile deprotection of the target compound enhances the practicality of this strategy.

关键词： palladium catalysis glycals tetrasubstitute olefins difunctionalization stereodefined threecomponent

Recovery of iron from copper tailings via low-temperature direct reduction and magnetic separation: process optimization and mineralogical study

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International Journal of Minerals,Metallurgy and Materials 2017年第9期24卷 974-982页

作者： rui-min jiao Peng Xing Cheng-yan Wang Bao-zhong Ma Yong-qiang Chen School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China

Currently, the majority of copper tailings are not effectively developed. Worldwide, large amounts of copper tailings generated from copper production are continuously dumped, posing a potential environmental threat. Herein, the recovery of iron from copper tailings via low-temperature direct reduction and magnetic separation was conducted; process optimization was carried out, and the corresponding mineralogy was investigated. The reduction time, reduction temperature, reducing agent (coal), calcium chloride additive, grinding time, and magnetic field intensity were examined for process optimization. Mineralogical analyses of the sample, reduced pellets, and magnetic concentrate under various conditions were performed by X-ray diffraction, optical microscopy, and scanning electron microscopy-energy-dispersive X-ray spectrometry to elucidate the iron reduction and growth mechanisms. The results indicated that the optimum parameters of iron recovery include a reduction temperature of 1150A degrees C, a reduction time of 120 min, a coal dosage of 25%, a calcium chloride dosage of 2.5%, a magnetic field intensity of 100 mT, and a grinding time of 1 min. Under these conditions, the iron grade in the magnetic concentrate was greater than 90%, with an iron recovery ratio greater than 95%.

关键词： copper tailings iron direct reduction magnetic separation recovery process optimization

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新质生产力的唯物史观意蕴

长江师范学院学报 2025年第1期41卷 25-33页

作者：周杰焦玉瑞上海财经大学马克思主义学院上海200433

新质生产力是唯物史观中国化时代化的术语表达,是马克思主义生产力理论与中国发展实际相结合的理论结晶,这也要求我们立足唯物史观来深刻理解生产力的时代内涵。新质生产力的形成和发展丰富、拓展了生产力、生产关系的内涵,彰显了社会... 详细信息

新质生产力是唯物史观中国化时代化的术语表达,是马克思主义生产力理论与中国发展实际相结合的理论结晶,这也要求我们立足唯物史观来深刻理解生产力的时代内涵。新质生产力的形成和发展丰富、拓展了生产力、生产关系的内涵,彰显了社会存在和社会意识的辩证统一,是中国共产党人发挥历史主动精神准确识别社会发展方位,应对社会发展问题的新思路,更是摆脱全球发展困境、把握历史大势的新创见。在新质生产力的构成要素中,生产力的历史性、科技异化的现实性和绿色发展的指向性决定了科技创新是新质生产力的核心要素,是对马克思“生产力中也包括科学”命题的现实发展。新质生产力将人的自由全面发展作为目标归宿,而人的自由全面发展又为新质生产力进一步发展提供智力支持,这充分彰显了中国特色社会主义的制度优势,也为中国式现代化建设提供了强大支撑。

关键词：新质生产力唯物史观人的自由全面发展社会存在社会意识

Electrodeposition of rare refractory metals in low-temperature ionic liquids

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Rare Metals 2024年第10期43卷 4921-4933页

作者： Lin-Lin Wang Han-Dong jiao rui Yuan Le-Yang Li Man-Peng Lin rui-Yang Sun Jiu-San Xiao Shu-qiang jiao Institute of Advanced Structure Technology Beijing Institute of TechnologyBeijing 100081China State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China

Rare refractory metals(RRMs)play a significant role in fundamental industries,including electronics,chemical industry,machinery,etc.,and future advanced fields,such as aerospace and ***,the traditional production processes of RRMs based on high-temperature thermal reduction cannot meet the requirements of low-energy *** dilemma could be addressed efficiently by using a low-temperature electrodeposition strategy in ionic liquids(ILs).This review summarizes a panoramic view of the latest developments on the electrodeposition of RRMs in ILs after a brief review on the current industrial production methods of *** on this,the electrochemical mechanism occurring at the cathode during the electrodeposition process of RRMs in different electrolytes and under different conditions is thoroughly discussed,because it is crucial for the successful production of pure *** addition,this review not only analyses the main challenges that hinder the industrial application of the electrodeposition of RRMs in ILs,but also proposes corresponding *** hope this review can provide a valuable guidance for the fundamental research and industrial development of lowtemperature electrodeposition of RRMs.

关键词： Rare refractory metals Ionic liquids Electrodeposition Production process

Bioconcentration of polycyclic aromatic hydrocarbons in roots of three mangrove species in Jiulong River Estuary

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Journal of Environmental Sciences 2005年第2期17卷 285-289页

作者： LUZhi-qiang ZHENGWen-jiao MALi SchoolofLifeSciences ResearchCentreforWetlandandEcologicalEngineeringXiamenUniversityXiamen361005China／／EnvironmentalScienceResearchCenterXiamenUniversityXiamen361005China SchoolofLifeSciences ResearchCentreforWetlandandEcologicalEngineeringXiamenUniversityXiamen361005China EnvironmentalScienceResearchCenter XiamenUniversityXiamen361005China

The polycyclic aromatic hydrocarbons(PAHs) concentrations were determined in the root of three mangrove species(Kandelia candel, Avicennia marina and Bruguiera gymnorrhiza) and their growing environment(sediment) in mangrove wetlands of Jiulong River Estuary, Fujian, China. The total PAHs(16 parent PAHs) in mangrove sediments ranged from 193.44 to 270.53 ng/g dw, with a mean value of 231.76±31.78 ng/g dw. Compared with other mangrove and coastal marine sediments, the PAHs concentrations of all the sampling areas in this study were at relatively lower level. The total PAHs(13 parent PAHs) values varied from 30.83 to 62.73 ng/g dw in mangrove roots. Benzo[a]pyrene(five-ring), fluoranthene(four-ring) and pyrene(four-ring) dominated in mangrove sediments. Based on ratios of phenathrene/anthracene, fluoranthene/pyrene and fluoranthene/pyrene + fluoranthene, the main possible sources of surface sediment PAHs were identified as grass, wood or coal combustion for mangrove wetlands of Jiulong River Estuary. Naphthalene(two-ring) and phenathrene(three-ring) were the most abundant compounds in mangrove roots. Sediment-to-vegetation bioconcentration factors(BCF SV s) were calculated and their relationships with PAHs' physico-chemical properties were investigated. The average BCF SV s of PAHs for three mangrove species roots were almost all under the level of 1 except for naphthalene. Good linear relationship between BCF SV values for mangrove roots and PAHs water solubility, octanol-water partitioning coefficients was derived in present study. The solubility and the octanol-water partition coefficient were proved to be good predictors for the accumulation of PAHs in mangrove roots, respectively.

关键词： mangrove PAHs Jiulong River Estuary bioconcentration factors

Constitutive Relation of Yunjialing Anthracite Under Medium Strain Rate

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Journal of China University of Mining and Technology 2007年第1期17卷 126-132页

作者： GAO Wen-jiao SHAN Ren-liang WANG Gong-cheng CHENG rui-qiang Department of Civil Engineering China University of Mining ＆ Technology Beijing 100083 China

By means of the split Hopkinson pressure bar （SHPB） testing system, this paper presents a dynamic constitu- tive relation of anthracite at a strain rate of ε =5-85s^-1. Generally, the dynamic stress-strain curve for this kind of anthracite under uni-axial compression has the following four stages： a non-linear loading stage, a plastic yielding stage, a strain-strengthening stage and an unloading breakage stage. Correspondingly, the initial elastic modulus Eb, the yielding strength σs and the ultimate strength σb increase along with an increasing strain rate. The time-dependent elasticity was identified when we analyzed the mechanical properties of anthracite. Based on characteristics of measured dynamic stress-strain curves and an analysis of existing rock dynamic constitutive models, as well as a preparatory simulation, a new visco-elastic damage model has been introduced in this paper. A linear spring is put parallel to two Maxwell units with different relaxation times to express two distinct plastic flows. The damage D is equal to [Eb- E（εi）]/Eb, where Eb is the beginning modulus and the E（εi） is the slope of a connected line between the origin point and any other point on a tested stress-strain curve. In the new constitutive model, one Maxwell unit with low relaxation time φ is used to describe the response of anthracite to a low strain rate, while the other, with a high relaxation time φ describes the response of anthracite to a high strain rate. Simulated stress-strain curves from the new model are consistent with the measured curves.

关键词： split Hopkinson pressure bar anthracite constitutive model dynamic properties strain rate

Individual aircraft life monitoring： An engineering approach for fatigue damage evaluation

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Chinese Journal of Aeronautics 2018年第4期31卷 727-739页

作者： rui jiao Xiaofan HE Yuhai LI School of Aeronautic Science and Engineering Beihang University Beijing 100083 China A viation Industry Corporation of China Beijng 100022 China

Individual aircraft life monitoring is required to ensure safety and economy of aircraft structure, and fatigue damage evaluation based on collected operational data of aircraft is an integral part of it. To improve the accuracy and facilitate the application, this paper proposes an engineering approach to evaluate fatigue damage and predict fatigue life for critical structures in fatigue monitoring. In this approach, traditional nominal stress method is applied to back calculate the S-N curve parameters of the realistic structure details based on full-scale fatigue test data. Then the S-N curve and Miner＇s rule are adopted in damage estimation and fatigue life analysis for critical locations under individual load spectra. The relationship between relative small crack length and fatigue life can also be predicted with this approach. Specimens of 7 B04-T74 aluminum alloy and TA15 M titanium alloy are fatigue tested under two types of load spectra, and there is a good agreement between the experimental results and analysis results. Furthermore, the issue concerning scatter factor in individual aircraft damage estimation is also discussed.

关键词： Fatigue damage Fatigue monitoring Fatigue test Scatter factor S-N curve

Smyd1 is essential for myosin expression and sarcomere organization in craniofacial,extraocular,and cardiac muscles

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Journal of Genetics and Genomics 2021年第3期48卷 208-218页

作者： Shuang jiao rui Xu Shaojun Du Department of Biochemistry and Molecular Biology Institute of Marine and Environmental TechnologyUniversity of Maryland School of MedicineBaltimoreMD 21202USA Key Laboratory of Experimental Marine Biology Center for Ocean Mega-ScienceInstitute of OceanologyChinese Academy of SciencesQingdao 266071China School of Life Sciences Shandong University of TechnologyZibo 255049China

Skeletal and cardiac muscles are striated myofibers that contain highly organized sarcomeres for muscle *** studies revealed that Smyd1,a lysine methyltransferase,plays a key role in sarcomere assembly in heart and trunk skeletal ***,Smyd1 expression and function in craniofacial muscles are not ***,we analyze the developmental expression and function of two smyd1 paralogous genes,smyd1 a and smyd1 b,in craniofacial and cardiac muscles of zebrafish *** data show that loss of smyd1a(smyd1a^(mb5))or smyd1b(smyd1b^(sa15678))has no visible effects on myogenic commitment and expression of myod and myosin heavy-chain m RNA transcripts in craniofacial ***,myosin heavy-chain protein accumulation and sarcomere organization are dramatically reduced in smyd1b^(sa15678) single mutant,and almost completely diminish in smyd1a^(mb5);smyd1b^(sa15678) double mutant,but not in smyd1a^(mb5) *** defects are also observed in cardiac muscles of smyd1b^(sa15678) *** craniofacial and cardiac muscle formation is associated with an upregulation of hsp90α1 and unc45b mRNA expression in smyd1b^(sa15678) and smyd1a^(mb5);smyd1b^(sa15678) ***,our studies indicate that Smyd1b,but not Smyd1a,plays a key role in myosin heavy-chain protein expression and sarcomere organization in craniofacial and cardiac *** of smyd1b results in muscle-specific stress response.

关键词： Smyd1 Myosin Sarcomere Craniofacial muscle Cardiac muscle

Environmental control of growth and BChl a expression in an aerobic anoxygenic phototrophic bacterium, Erythrobacter longus (DSMZ6997)

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Acta Oceanologica Sinica 2006年第6期25卷 138-144页

作者： LI qiang jiao Nianzhi PENG Zaiqing State Key Laboratory of Marine Environmental Science Xiamen University Xiamen 361005 China

anoxygenic phototrophic bacteria （AAPB）, which form a unique functional group of heterotrophic bacteria, have the abilit,to utilize light energy. The impact of carbon source and light intensity on the growth and bacteriochlorophyn a （ BChl a） expression of a typical strain of AAPB, Erythrobacter longus strain DSMZ6997 was examined during batch culture and continuous culture. The results showed that the expression of BChl a in DSMZ6997 was regulated by both carbon-source and light conditions, and was stimulated by low availability of carbon but inhibited by light to a certain extent at 300 lx and completely at 1 500 lx. In contrast, cell abundance, and even cell size of this strain, was substantially enhanced under light/dark cycle cultivation conditions over dark conditions, indicating the promotion of growth by light. These results led to the conclusion that utilization of light through BChl a helps AAPB to survive under carbon stress, while light at high intensity is harmful to the synthesis of BChl a in AAPB.

关键词： aerobic anoxygenic phototrophic bacteria ( AAPB) bacteriochlarophyll a ( BChl a) continuous culture