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Science china Chemistry 2024年第2期67卷 576-586页

作者： Xiao-Bao Wu Jun-Xiu Shi Yi-Ming Ou Hua-jie Jiang Yi-Jun fang Qi-Ming Wang Quan Gao jie Yu department of Applied Chemistry Anhui Province Engineering Laboratory for Green Pesticide Development and ApplicationAnhui Province Key Laboratory of Crop Integrated Pest ManagementAnhui Agricultural UniversityHefei230036China

A privileged strategy has been developed for the precise construction of enantioenriched azaspiro polycyclic *** diverse azaspiro polycycles bearing multiple contiguous stereocenters are obtained with excellent results(up to 99:1 e.r.,>95:5 d.r.) via sequential enantioselective four-component Ugi reactions/post-Ugi transformations with substrates containing prerequisite functional groups in the presence of anionic stereogenic-at-cobalt(Ⅲ) complexes.

关键词： asymmetric catalysis post-Ugi transformation anionic stereogenic-at-cobalt(Ⅲ)complex azaspiro polycyclic scaffold one-pot synthesis

SIMPLE OCKHAM ALGEBRAS

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Chinese Annals of Mathematics,Series B 1996年第2期17卷 213-218页

作者： fang jie department of Mathematics, Zhongshan university, {3. 510271, china. department of Mathematics Zhongshan University Guangzhou 510271 China

An algeber L is said to be simple, if its congruence lattice Con L reduces to the 2-elementchain {ω,v}. This paper describes the structure of finite simple Ockham algebras.

关键词： Ockham algebra Simple algebra Congruence lattic 2-element chain

Effect of electrical parameters and slag system on macrostructure of electroslag ingot

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china Foundry 2024年第1期21卷 44-50页

作者： Bing-jie Wang Yu Wang Meng-jun Wang Lei Zhao Li-zhong Chang Xiao-fang Shi School of Metallurgy engineering Anhui University of TechnologyMa'anshan 243002AnhuiChina

To investigate the influence of electric parameters and slag system on the solidification quality of electroslag ingot during electroslag remelting,different power supply modes,current strengths and remelting slag systems were used to conduct electroslag remelting experiments on 3.4L austenitic stainless steel,and the macrostructure of electroslag ingots was *** results indicate that the depth of the metal pool decreases with the reduction of remelting frequency in the low frequency power supply *** effects of different power supply modes,such as low-frequency,direct current straight polarity(DCSP),and direct current reverse polarity(DCRP),on reducing the depth of the metal pool increase in that *** reducing the remelting current strength in the same power supply mode,the depth of metal pool is *** compared to the binary slag system of 70%CaF2+3.%Al2O3.the ternary slag system of 60%CaF2+20%Al2O3.20%CaO is more effective in reducing the depth of the metal pool during *** the 60%CaF2+20%Al2O3.20%CaO ternary slag system results in a shallower and flatter metal pool,with columnar crystal growth occurring closer to the axial *** effect is observed for both low frequency and direct current(DC)power supply modes.

关键词： electroslag remelting frequency slag system solidification quality

Experimental study on wax deposition of highly paraffinic oil in intermittent gas-oil flow in pipelines

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Petroleum Science 2024年第3期21卷 2080-2088页

作者： Chuan-Shuo Wang Qian-Li Ma Xiao-fang Lv jie Zhang Yang Liu Shi-Dong Zhou Jiangsu Key Laboratory of Oil and Gas Storage and Transportation Technology Changzhou UniversityChangzhou213164JiangsuPR China Hade Oil and Gas Development department Tarim Oilfield BranchKorla841000XinjiangPR China

Oil-gas two phase wax deposition is a fairly common and open-ended question in flow assurance of multiphase transportation *** paper investigated the two main aspects of oil-gas two phase wax deposition layer:apparent thickness and crystal structure characteristics.A typical highly paraffinic oil in Bohai Sea,china,was used as the experimental material to investigate the wax deposition thickness in oil-gas two phase under the influence of different oil temperatures,superficial gas/liquid phase velocities and gas-oil ratios by using multiphase flow loop experimental *** as in the classical theory of wax molecular diffusion,it showed that wax deposition thickness of oil-gas two phase increased with increasing oil *** of the impact of different superficial phase velocities found that the actual liquid flow heat transfer and shear stripping was the gas phase dominant mechanisms determining wax deposit *** addition,the crystal structure of the wax deposition layer was characterized with the help of small-angle X-ray scattering(SAXS)for different circumferential positions,flow rates and gas-oil *** bottom deposition layer had a complex crystal structure and high hardness,which were subject to change over flow rate ***,the SAXS results provided evidence that the indirect effect of the actual liquid velocity modified by the gas phase was the main *** study of the effect of gas phase on the wax deposition of oil-gas two phase will help shed light onto the mechanism by which this important process *** findings address a very urgent need in the field of wax deposition of highly paraffinic oil to understand the flow security of oilgas two phase that occurs easily in multiphase field pipelines.

关键词： Oil-gas two phase Highly paraffinic oil Wax deposition SAXS

Superatomic Ag58 nanoclusters incorporating a [MS4@Ag12]2+（M = Mo or W） kernel show aggregation-induced emission

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Chinese Chemical Letters 2024年第10期35卷 478-482页

作者： Jun-jie fang Zheng Liu Yun-Peng Xie Xing Lu State Key Laboratory of Materials Processing and Die & Mould Technology School of Materials Science and Engineering Huazhong University of Science and Technology

In core-shell silver nanoclusters, the control of core structure presents a more formidable challenge compared to that of the shell structure. Here, we report the successful synthesis and characterization of four distinct silver thiolate nanoclusters [MS4@Ag12@Ag46S24（dppb）12]（M = Mo or W）, each incorporating a cup-like [MS4@Ag12]2+kernel. These nanoclusters were meticulously prepared using（NH4）2Mo S4or（NH4）2WS4as both a template and a controlled source of S2-ions. Remarkably, we have observed a unique configuration within these eight-electron superatomic Ag58nanoclusters, where the zerovalent Ag atoms reside exclusively within the inner [MS4@Ag12]2+kernel. This stands in contrast to other superatomic clusters possessing an Ag（0） core. Notably, the introduction of phenyl-containing compounds during the synthesis process induced a transformation in the space group symmetry from C2/c to I 4ˉ. This transformative effect was found to originate from the interplay between adjacent 1,4-bis（diphenylphosphino）butane（dppb） ligands, which facilitated enhanced emission through aggregationinduced intermolecular interactions, specifically C-H···π interactions. Collectively, our findings contribute substantively to the understanding of the intricate relationship between nanocluster structures and their corresponding properties, shedding light on the crucial roles played by templates and diphosphine ligands in this context.

关键词： Superatom Silver nanocluster Template synthesis Photoluminescence Aggregation -induced emission SILVER NANOCLUSTERS OPTICAL-PROPERTIES CLUSTERS THIOLATE NANOPARTICLES TRANSFORMATION CORE

Hydrocarbon Charging and Accumulation Process of the Large Bozhong19-6 Condensate Gas Reservoirs in the Southwestern Bozhong Sub-Basin,Bohai Bay Basin,china

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Journal of Earth Science 2024年第2期35卷 613-630页

作者： Quanyun Miao Changgui Xu fang Hao Minjunshi Xie Qi Wang jie Yin Huayao Zou General Prospecting Institute of china National Administration of Coal Geology Beijing100039China State Key Laboratory of Petroleum Resource and Prospecting China University of PetroleumBeijing102249China Tianjin Branch of china National Offshore Oil Company Ltd. Tianjin300452China School of Geosciences China University of PetroleumQingdao266580China School of Geosciences Yangtze UniversityWuhan430100China

The Bozhong19-6(BZ19-6)condensate gas reservoirs,located in the southwestern Bozhong sub-basin,Bohai Bay Basin,china,were paleo-oil reservoirs in the geological past and have undergone at least three successive hydrocarbon charging *** hydrocarbon migration and accumulation process of“early oil and late gas”has occurred in the current *** the end of the sedimentation of the Guantao Formation(N_(1)g,∼12 Ma),the reservoirs began to fill with first stage low-moderate mature crude *** the late stage of the Lower Minghuazhen Formation(N_(1)ml)(∼6.7 Ma),the reservoirs were largely charged with second stage high mature crude *** the deposition of the upper Minghuazhen Formation(N_(2)m^(u),∼5.1 Ma),the paleo-oil reservoirs were transformed into shallow Neogene reservoirs due to the reactivation of basement *** the late stage of the N_(2)m^(u)to the present day(∼2.8–0 Ma),the reservoirs were rapidly filled by natural gas within a short *** addition,analysis of the formation of the reservoir bitumen and the conspicuous loss of the lower molecular weight n-alkanes in the crude oil reveal that the injection of a large amount of gas in the late stage caused gas flushing of the early charged oil.

关键词： Bohai Bay Basin BZ19-6 condensate gas reservoirs fluid inclusions hydrocarbon charging and accumulation petroleum geology

The role and applications of extracellular vesicles in osteoporosis

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Bone Research 2024年第1期12卷 62-77页

作者： Fei fang jie Yang Jiahe Wang Tiantian Li Erxiang Wang Demao Zhang Xiaoheng Liu Chenchen Zhou Institute of Biomedical Engineering West China School of Basic Medical Sciences&Forensic MedicineSichuan UniversityChengdu 610041China State Key Laboratory of Oral Diseases National Clinical Research Center for Oral DiseasesWest China Hospital of StomatologySichuan UniversityChengdu 610041China

Osteoporosis is a widely observed condition characterized by the systemic deterioration of bone mass and microarchitecture,which increases patient susceptibility to fragile *** intricate mechanisms governing bone homeostasis are substantially impacted by extracellular vesicles(EVs),which play crucial roles in both pathological and physiological *** derived from various sources exert distinct effects on ***,EVs released by osteoblasts,endothelial cells,myocytes,and mesenchymal stem cells contribute to bone formation due to their unique cargo of proteins,miRNAs,and ***,EVs secreted by osteoclasts and immune cells promote bone resorption and inhibit bone ***,the use of EVs as therapeutic modalities or biomaterials for diagnosing and managing osteoporosis is ***,we review the current understanding of the impact of EVs on bone homeostasis,including the classification and biogenesis of EVs and the intricate regulatory mechanisms of EVs in ***,we present an overview of the latest research progress on diagnosing and treating osteoporosis by using ***,we discuss the challenges and prospects of translational research on the use of EVs in osteoporosis.

关键词： osteoporosis homeostasis biomaterials

Förster resonance energy transfer reveals phillygenin and swertiamarin concurrently target AKT on different binding domains to increase the anti-inflammatory effect

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Chinese Chemical Letters 2024年第5期35卷 207-212页

作者： Xiaoyao Ma Jinling Zhang Ge fang He Gao jie Gao Li Fu Yuanyuan Hou Gang Bai State Key Laboratory of Medicinal Chemical Biology College of Pharmacy and Tianjin Key Laboratory of Molecular Drug ResearchNankai UniversityTianjin 300000China College of Life Health Dalian UniversityDalian 116622China Dalian Fusheng Pharmaceutical Co. Ltd.Dalian 116000China

The clinical benefit of combination therapy is significant,but it is not easy to define the mechanism of complexity and *** studies illustrate that phillygenin(Phi)binds in the allosteric inhibit pocket of protein kinase B(AKT),and swertiamarin(Swe)acts on the pleckstrin homology(PH)domain of ***,the combined synergistic effect of relieving the inflammatory response has yet to be *** on high sensitivity,specificity and fast-responsibility fluorescent sensors,the Förster resonance energy transfer(FRET)technique offers a route to provide clear insights into physiological and pathological *** the study,molecular docking,the fluorescent probes of Phi and Swe for FRET were designed and *** analysis shown that Swe and Phi concurrently acted on the PH domain and allosterically inhibited pocket of AKT,*** combination of Swe and Phi significantly increased the heat stability of AKT and decreased protease-induced *** lipopolysaccharides(LPS)-induced mice and cells,the combination arrested AKT activation,nuclear factor kappa-B(NF-κB)phosphorylation,and the expression of tumor necrosis factor-α(TNF-α),interleukin(IL)-6 and *** conclusion,FRET revealed Phi and Swe concurrently targeted AKT on different domains and the combination of Phi and Swe enhanced the anti-inflammatory effect.

关键词： FRET Swertiamarin Phillygenin AKT Anti-inflammation Combinatorial drug

Role of alloying and heat treatment on microstructure and mechanical properties of cast Al-Li alloys:A review

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china Foundry 2024年第5期21卷 445-460页

作者： Guo-hua Wu You-jie Guo fang-zhou Qi Shen Zhang Yi-xiao Wang Xin Tong Liang Zhang School of Materials Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China

Due to the prominent advantages of low density,high elastic modulus,high specific strength and specific stiffness,cast Al-Li alloys are suitable metallic materials for manufacturing complex large-sized components and are ideal structural materials for aerospace,defense and military *** the basis of the microstructural characteristics of cast Al-Li alloys,exploring the role of alloying and micro-alloying can stabilize their dominant position and further expand their application *** this review,the development progress of cast Al-Li alloys was summarized *** to the latest research highlights,the influence of alloying and heat treatment on the microstructure and mechanical properties was systematically *** potential methods to improve the alloy performance were *** response to the practical engineering requirements of cast Al-Li alloys,the scientific challenges and future research directions were discussed and prospected.

关键词： cast Al-Li alloy alloying microstructure mechanical properties heat treatment

Durable K-ion batteries with 100% capacity retention up to 40,000 cycles

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Carbon Energy 2024年第5期6卷 201-212页

作者： Xianlu Lu Zhao Liang Zhi fang Dongdong Zhang Yapeng Zheng Qiao Liu Dingfa Fu jie Teng Weiyou Yang Institute of Micro/Nano Materials and Devices Ningbo University of TechnologyNingboZhejiangChina College of Materials Science and Engineering Hunan UniversityChangshaChina College of Mechanical and Vehicle Engineering Hunan UniversityChangshaChina

Currently,the major challenge in terms of research on K-ion batteries is to ensure that they possess satisfactory cycle stability and specific capacity,especially in terms of the intrinsically sluggish kinetics induced by the large radius of K+***,we explore high-performance K-ion half/full batteries with high rate capability,high specific capacity,and extremely durable cycle stability based on carbon nanosheets with tailored N dopants,which can alleviate the change of volume,increase electronic conductivity,and enhance the K+ion *** as-assembled K-ion half-batteries show an excellent rate capability of 468 mA h g^(−1) at 100 mA g^(−1),which is superior to those of most carbon materials reported to ***,the as-assembled half-cells have an outstanding life span,running 40,000 cycles over 8 months with a specific capacity retention of 100%at a high current density of 2000 mA g^(−1),and the target full cells deliver a high reversible specific capacity of 146 mA h g^(−1) after 2000 cycles over 2 months,with a specific capacity retention of 113.at a high current density of 500 mA g^(−1),both of which are state of the art in the field of K-ion *** study might provide some insights into and potential avenues for exploration of advanced K-ion batteries with durable stability for practical applications.

关键词： carbon nanosheet cycle stability K-ion batteries rate performance specific capacity