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Nature and timing of a prehistoric giant landslide on the eastern margin of the Tibetan Plateau

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Journal of Mountain Science 2020年第6期17卷 1438-1451页

作者： ZHAO Xun WANG Yun-sheng WANG Shi-yuan ZHAO Bo ZENG Lu LIU Yu feng qian-qian State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of TechnologyChengdu 610059China Sichuan Earthquake Agency Chengdu 610041China Key Laboratory of Mountain Hazards and Earth Surface Processes Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu 610041China

Studying the characteristics of a prehistoric giant landslide and ascertaining its relationship with palaeo-seismic events could provide useful information on the role of regional tectonic activities in hillslope ***,a giant palaeoseismic landslide(GPSL),namely,the Luanshibao(LSB)landslide,located on the eastern margin of the Qinghai-Tibet Plateau,was investigated to ascertain its characteristics and occurrence *** relationship between occurrence age and palaeoseismic episodes was also discussed by using 14 C dating on the adjacent active faults,including the regional Yidun-Litang-Dewu(YD-LT-DW)fault zone,which crossed the LSB *** dating of multiple samples acquired from palaeo-seismic trenches revealed that at least 5 palaeo-seismic episodes had occurred in the vicinity of the LSB landslide over the last 5000 *** occurrence age of the LSB landslide(3635±387 a BP)coincides with palaeo-seismic episode I,and the LSB landslide is convincingly inferred to have been triggered during episode I,which reached a seismic intensity(Chinese scale)of at least degree VII near the LSB landslide during *** timing of a second reactivation phase coincides with palaeo-seismic episode IV,which occurred at 2100-2200 a *** study could provide reference for studying the regional palaeoseismic activities and palaeo landslide evolution near the Litang area.

关键词： Prehistoric landslide Active fault zone Palaeo-seismic episode Dating

Mechanistic insights into stepwise activation of malachite for enhancing surface reactivity and flotation performance

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International Journal of Minerals,Metallurgy and Materials 2024年第10期31卷 2159-2172页

作者： Qicheng feng Wanming Lu Han Wang qian Zhang State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization Faculty of Land Resource EngineeringKunming University of Science and TechnologyKunming 650093China Yunnan Key Laboratory of Green Separation and Enrichment of Strategic Mineral Resources Kunming University of Science and TechnologyKunming 650093China

Malachite is a common copper oxide mineral that is often enriched using the sulfidization-xanthate flotation ***,the direct sulfidization method cannot yield copper concentrate ***,a new sulfidization flotation process was developed to promote the efficient recovery of *** this study,Cu^(2+) was used as an activator to interact with the sample surface and increase its reaction sites,thereby strengthening the mineral sulfidization process and *** to single copper ion activation,the flota-tion effect of malachite significantly increased after stepwise Cu^(2+) *** potential,X-ray photoelectron spectroscopy(XPS),time-of-flight secondary ion mass spectroscopy(ToF-SIMS),scanning electron microscopy and energy dispersive spectrometry(SEM-EDS),and atomic force microscopy(AFM)analysis results indicated that the adsorption of S species was significantly enhanced on the mineral surface due to the increase in active Cu sites after Cu^(2+) stepwise ***,the proportion of active Cu-S spe-cies also increased,further improving the reaction between the sample surface and subsequent ***-transform infrared spec-troscopy(FT-IR)and contact angle tests implied that the xanthate species were easily and stably adsorbed onto the mineral surface after Cu^(2+) stepwise activation,thereby improving the hydrophobicity of the mineral ***,the copper sites on the malachite sur-face after Cu^(2+) stepwise activation promote the reactivity of the mineral surface and enhance sulfidization flotation of malachite.

关键词： malachite copper ions stepwise activation flotation mechanism enhanced sulfidization

Remote copper-catalyzed enantioselective substitution of yne-thiophene carbonates

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Science China Chemistry 2024年第4期67卷 1175-1180页

作者： Hao-Dong qian Xiang Li Tingrui Yin Wei-feng qian Chunhui Zhao Cuiju Zhu Hao Xu CCNU-uOttawa Joint Research Centre Key Laboratory of Pesticides&Chemical Biology of Ministry of EducationInternational Joint Research Center for Intelligent Biosensing Technology and HealthCollege of ChemistryCentral China Normal UniversityWuhan 430079China

Here,we describe a strategy for the copper-catalyzed asymmetric heteroarylation of yne-thiophene carbonates with indoles via remote *** key to the success of this strategy lies in the design of the alkynyl group at the ortho-position of the heterocycle thiophene,enabling the formation of a triarylmethane moiety via very remote ***,the concept of remote copper-catalyzed asymmetric transformation extends not only to yne-allylic esters but also to yne-aryl *** reaction readily provides a diverse array of chiral triarylmethanes with high efficiency,enantioselectivity,and excellent functional group ***,facile follow-up transformations underscore their potential utility in the synthesis of various enantioenriched building *** mechanistic studies support the plausibility of the remote substitution pathway.

关键词： remote substitution copper catalyst asymmetric catalysis triaryl methanes

Biomimetic chitin hydrogel via chemical transformation

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Nano Research 2024年第2期17卷 771-777页

作者： Rui-Rui Liu qian-qian Shi Yu-feng Meng Yong Zhou Li-Bo Mao Shu-Hong Yu Division of Nanomaterials&Chemistry Hefei National Research Center for Physical Sciences at the MicroscaleDepartment of ChemistryInstitute of Biomimetic Materials&ChemistryAnhui Engineering Laboratory of Biomimetic MaterialsUniversity of Science and Technology of ChinaHefei 230026China College&Hospital of Stomatology Key Laboratory of Oral Diseases Research of Anhui ProvinceAnhui Medical UniversityHefei 230032China Department of Dental Implantology College&Hospital of StomatologyAnhui Medical UniversityHefei 230032China

Chitin hydrogel has been recognized as a promising material for various biomedical applications because of its biocompatibility and ***,the fabrication of strong chitin hydrogel remains a big challenge because of the insolubility of chitin in many solvents and the reduced chain length of chitin regenerated from *** herein introduce the fabrication of chitin hydrogel with biomimetic structure through the chemical transformation of chitosan,which is a water-soluble deacetylated derivative of *** reacetylation of the amino group in chitosan endows the obtained chitin hydrogel with outstanding resistance to swelling,degradation,extreme temperature and pH conditions,and organic *** chitin hydrogel has excellent mechanical properties while retaining a high water content(more than 95 wt.%).It also shows excellent antifouling performance that it resists the adhesion of proteins,bacteria,blood,and ***,as the initial chitosan solution can be feasibly frozen and templated by ice crystals,the chitin hydrogel structure can be either nacre-like or wood-like depending on the freezing method of the precursory chitosan *** to these anisotropic structures,such chitin hydrogel can exhibit anisotropic mechanics and mass transfer *** current work provides a rational strategy to fabricate chitin hydrogels and paves the way for its practical applications as a superior biomedical material.

关键词： chitin hydrogel biomimetic structure chemical stability mechanical strength antifouling

Curation,nomenclature,and topological classification of receptor-like kinases from 528 plant species for novel domain discovery and functional inference

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Molecular Plant 2024年第4期17卷 658-671页

作者： qian Liu Qiong Fu Yujie Yan qian Jiang Longfei Mao Long Wang feng Yu Heping Zheng State Key Laboratory of Chemo/Biosensing and Chemometrics Hunan University College of BiologyChangshaHunan 410082China Bioinformatics Center Hunan University College of BiologyChangshaHunan 410082China

Receptor-like kinases(RLKs)are the most numerous signal transduction components in plants and play important roles in determining how different plants adapt to their ecological *** on RLKs has focused mainly on a small number of typical RLK members in a few model *** is an urgent need to study the composition,distribution,and evolution of RLKs at the holistic level to increase our understanding of how RLKs assist in the ecological adaptations of different plant *** this study,we collected the genome assemblies of 528 plant species and constructed an RLK *** this dataset,we identified and characterized 524948 RLK family *** member underwent systematic topological classification and was assigned a gene ID based on a unified nomenclature ***,we identified two novel extracellular domains in some RLKs,designated Xiao and *** analysis of the RLK family revealed that the RLCK-XVII and RLCK-XII-2 classes were present exclusively in dicots,suggesting that diversification of RLKs between monocots and dicots may have led to differences in downstream cytoplasmic *** also used an interaction proteome to help empower data mining for inference of new RLK functions from a global perspective,with the ultimate goal of understanding how RLKs shape the adaptation of different plants to the environments/*** assembled RLK dataset,together with annotations and analytical tools,forms an integrated foundation of multiomics data that is publicly accessible via the metaRLK web portal(http://***).

关键词： RLK RLCK domain signaling pathway receptor-protein interactions

Deep Learning based Efficient Edge Slicing for System Cost Minimization in Wireless Networks

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Journal of Communications and Information Networks 2024年第2期9卷 162-175页

作者： Wei Jiang Daquan feng Liping qian Yao Sun College of Information Engineering Zhejiang University of TechnologyHangzhou 310023China Shenzhen Key Laboratory of Digital Creative Technology Guangdong Province Engineering Laboratory for Digital Creative TechnologyCollege of Electronics and Information EngineeringShenzhen UniversityShenzhen 518060China James Watt School of Engineering University of GlasgowG128QQScotlandUK

It is widely recognized that the future wireless networks are able to efficiently slice heterogeneous resources to provide customized services for various use cases. However, it is challenging to meet the diverse requirements of ever-growing applications, especially the stringent requirements of numerous delay-sensitive and/or computation-intensive applications. To tackle this challenge, we should not only consider user admission control to cope with resource limitations, but also make resource management more intelligent and flexible to meet diverse service needs. Taking advantages of mobile edge computing(MEC)and network slicing, in this paper, we propose deep edge slicing(DES),to jointly optimize user admission control and resource scheduling with the aim of minimizing the system cost while guaranteeing multitudinous quality-of-service (QoS) requirements. Specifically, we first apply a deep reinforcement learning approach to select the optimal set of access users with different service requests for maximizing resource *** a deep learning algorithm is employed to predict traffic data for allocating the communication and computing resources to different slices in advance. Finally, we realize the dynamic scheduling of heterogeneous resources by solving the optimization problem of minimizing the system cost. Simulation results demonstrate that DES can greatly reduce the system cost compared to other benchmarks.

关键词： deep learning mobile edge computing user admission control resource scheduling

Artificial intelligence-assisted design of new chemical materials: a perspective

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Science China(Information Sciences) 2024年第8期67卷 334-336页

作者： feng qian Wenli DU Weimin ZHONG Yang TANG Jingyi LU Key Laboratory of Smart Manufacturing in Energy Chemical Process Ministry of EducationEast China University of Science and Technology

New chemical materials are a fresh category of substances created through chemical reactions or by refining existing materials through secondary processes. By using creative methods, advanced technologies, innovative techniques, and state-of-the-art equipment, these materials(e.g., high-end polyolefin, nano materials) [1] are carefully designed and developed to showcase outstanding performance and unique capabilities beyond what traditional chemical materials can offer [2].

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Efflcient machining of a complex blisk channel using a disc cutter

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Chinese Journal of Aeronautics 2024年第1期37卷 414-437页

作者： Xiangyu LI Zhaoyu LI Dong HE Junxue REN qian feng Kai TANG Department of Mechanical and Aerospace Engineering Hong Kong University of Science and TechnologyHong Kong 999077China Key Laboratory of High Performance Manufacturing for Aero Engine(Northwestern Polytechnical University) Ministry of Industry and Information TechnologyXi’an 710072China Xi’an Sanhang Power Technology Co. LtdXi’an 710000China HKUST Shenzhen-Hong Kong Collaborative Innovation Research Institute FutianShenzhen 518057China HKUST Shenzhen Research Institute Shenzhen 518057China

For rough machining of a complex narrow cavity,e.g.,a complex blisk channel on an aero-engine,the typically used cutting tools are the slender cylindrical cutter and conical ***,as neither of the two is particularly suited for rough machining,wherein the main purpose is to remove a large volume as quickly as possible,the machining efficiency is low,especially when the part materials are of hard-to-cut types(e.g.,Titanium-alloy)for which it often takes days to rough machine a ***,disc machining provides a new and efficient roughing solution,since a disc cutter with a large radius enables a much larger cutting speed and thus a larger material removal ***,due to the large radius of the disc cutter,its potential collision with narrow and twisted channels becomes a serious *** this paper,we propose a novel twophase approach for efficiently machining a complex narrow cavity workpiece using a disc-shaped cutter,i.e.,3+2-axis disc-slotting of the channel by multiple layers(rough machining)+five-axis disc-milling of the freeform channel side surfaces(semi-finish machining).Both simulation and physical cutting experiments are conducted to assess the effectiveness and advantages of the proposed *** experimental results show that,with respect to a same cusp-height threshold on the channel side surfaces,the total machining time of the tested part by the proposed method is about only 36%of that by the conventional approach of plunging-milling(for roughing)plus milling by a slender cylindrical cutter(for semi-finishing).

关键词： Blisk channel CNC machining Disc cutter Roughing efficiency Tool path planning

The Adjustment Analysis Method of the Active Surface Antenna Based on Convolutional Neural Network

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Research in Astronomy and Astrophysics 2024年第6期24卷 294-306页

作者： You Ban Shang Shi Na Wang qian Xu Shufei feng School of Mechanical Engineering Xinjiang UniversityUrumqi 830017China Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China School of Mechanical Engineering Dongguan University of TechnologyDongguan 523808China

Active surface technique is one of the key technologies to ensure the reflector accuracy of the millimeter/submillimeter wave large reflector *** antenna is complex,large-scale,and high-precision equipment,and its active surfaces are affected by various factors that are difficult to comprehensively deal *** this paper,based on the advantage of the deep learning method that can be improved through data learning,we propose the active adjustment value analysis method of large reflector antenna based on deep *** method constructs a neural network model for antenna active adjustment analysis in view of the fact that a large reflector antenna consists of multiple panels spliced *** on the constraint that a single actuator has to support multiple panels(usually 4),an autonomously learned neural network emphasis layer module is designed to enhance the adaptability of the active adjustment neural network *** classical 8-meter antenna is used as a case study,the actuators have a mean adjustment error of 0.00252 mm,and the corresponding antenna surface error is0.00523 *** active adjustment result shows the effectiveness of the method in this paper.

关键词： techniques:radar astronomy telescopes methods:analytical methods:numerical