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The earliest evidence for a microblade adaptation in the remote,high altitude regions of the Tibetan Plateau

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Science China Earth Sciences 2024年第5期67卷 1561-1573页

作者： Yingshuai JIN Xiaoling ZHANg Shejiang wa.g Junyi gE Wei HE wa DA Yunyao TAN ziyi YANg Christopher MORgAN Xing gAO Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of SciencesBeijing 100044China University of the Chinese Academy of Sciences Beijing 100049China Cultural Relics Conservation Institute of the Xizang Autonomous Region Lhasa 850000China Nagqu Culture and Tourism Bureau Nagqu 852000China University of Nevada Reno 89557USA

Microblade assemblages are among the most common prehistoric archaeological materials found on the Tibetan Plateau(TP)and are thought to indicate large scale migration to and settlement of the *** microblade sites,however,have been systematically excavated,especially in the remotest,highest-elevation regions of the *** timing of the large-scale arrival,spread,and permanent settlement of people on the TP therefore remains *** this paper,we report on a recently excavated site,Locality 3 of the Nwya Devu Site(ND3),located at 4600 meters above sea level(masl),near the shore of Ngoin Lake,on the interior *** analyses reveal a fairly typical microblade technological orientation and two types of microblade cores:wedge-shaped and semi-conical,which are similar to those found throughout North *** Optically Stimulated Luminescence(OSL)dating and AMS^(14)C dating,the age of ND3 ranges from 11 to 10 *** date range indicates ND3 is the oldest microblade site yet recorded in the remote,high-elevation regions of the TP and thus provides important information about when and how hunter-gatherers using microblades began exploiting the higher altitudes of the *** together,studies at ND3 and throughout the TP suggest that a microblade adaptation is associated with the first prolonged human occupation of the plateau and that microblades played a significant role in mediating the risks and facilitating the mobility necessary to permanently inhabit the TP.

关键词： The interior of Tibetan Plateau Nwya Devu locality 3 Microblade Early Holocene High altitude adaption

Strengthening and control of second-phase particle precipitation in ferritic/austenitic/martensitic heat-resistant alloys:a review

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Journal of Iron and Steel Research International 2024年第1期31卷 3-23页

作者： Xue-cheng Peng Han-jie guo Xin-fang Zhang Yi-wa Luo Ye Sun Jing guo Rong-guang Yang Xiao-dan Zheng School of Metallurgical and Ecological Engineering University of Science and Technology Beijing(USTB)Beijing100083China Beijing Key Laboratory of Special Melting and Preparation of High-End Metal Materials University of Science and Technology Beijing(USTB)Beijing100083China Beijing Shougang gitane New MATERIALS Co. Ltd.Beijing102206China

Heat-resistant alloys with excellent mechanical properties are widely used in various fields,and further improvement in their properties is essential to meet the requirements in new-generation advanced supercritical boilers,nuclear reactors,superheaters,and other new materials *** effectively enhance the comprehensive performance of heat-resistant alloys,second-phase particle strengthening has been widely studied,and in the face of different service envi-ronments of advanced heat-resistant steels,the selection of suitable second-phase particles is essential to maximize the performance of these *** this end,three major types of reinforcing phases in heat-resistant alloys such as carbides,rare earth oxides,and intermetallic compounds are summarized.A comparative analysis of the precipitation behavior of the reinforcing phases with different types as well as the risks and means of controlling their use in service,is *** parameters for the application of various types of second-phase particles in heat-resistant alloys are provided to support the design and preparation of new ultrahigh-performance heat-resistant alloys.

关键词： Heat-resistant alloy Second-phase particle Carbide Rare earth oxide Intermetallic compound Strengthening

Deuterium distribution and behavior of blisters in pre-damaged and undamaged tungsten

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Tungsten 2024年第3期6卷 647-656页

作者： Cong Li Xiao-wa wa.g Ran-Ran Su Xuan-Xin Hu Shu-guang Wei Han-Jun Tu Li-Qun Shi Hong-Liang Zhang Key Laboratory of Nuclear Physics and Ion-Beam Application Institute of Modern Physics Fudan University School of Mechanical Engineering Shanghai Jiao Tong University Department of Materials Science and Engineering University of Wisconsin

Tungsten(W),as a plasma-facing material,is subjected to high fluence plasma,resulting in both radiation damage and deuterium(D) *** study explores the blistering behavior and D supersaturated layers in both pre-damaged and undamaged W *** achieve a uniform damage profile similar to neutron irradiation,carbon(C) ions with multiple energies and angles were *** samples were further irradiated with low-energy D ions under two fluences at temperatures from ～380 to 640 *** various experimental techniques,we found that pre-damaged W samples can effectively suppress the formation of blistering and lower the threshold temperature at which the surface remains free of *** also observed the prominent D supersaturated peaks within the depth of 20 nm in both pre-damaged and undamaged ***,a close correlation between blistering and the D supersaturation was *** results suggest that neutron irradiation in the fusion reactors could increase the critical D concentration for blistering,while a greater depth of damage facilitated the inward diffusion of D,thereby reducing the D concentration gradient and alleviating surface blistering.

关键词： Tungsten Deuterium Supersaturated layer Blister Ion irradiation Pre-damage

Supramolecular Manipulation of Intracellular Acidic Vesicles to Improve Cellular Self-Repair and Self-Defense

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CCS Chemistry 2024年第6期6卷 1487-1498页

作者： ziyi wa.g Chen Sun Yu Dong Yuan-Fu Ding Chen Zhao Ian wa Ho Jiahong Lu Ruibing wa.g State Key Laboratory of Quality Research in Chinese Medicine Institute of Chinese Medical SciencesUniversity of MacaoTaipaMacao 999078China

Lysosomes are the“cell stomach”that digests various species including macromolecules and pathogens for self-repair and self-defense upon fusion with endosomes,autophagosomes,and ***,artificially manipulating intracellular vesicles could potentially promote lysosome-mediated intracellular digestion for disease prevention and ***,a supramolecular strategy to efficiently tether and fuse acidic vesicles(i.e.,lysosomes,late endosomes,autolysosomes,and phagosomes)has been developed for the first time to enhance the digestion of cellular wastes and foreign matter,including pathogens.A linear polyethylene glycol(PEg)derivative dually tagged with morpholine(MOR)and adamantane(ADA)on the opposite side,namely,MOR-PEg-ADA,was designed to target intracellular acidic vesicles via MOR and to decorate their surfaces with ***,the addition of cucurbit[7]uril(CB[7])grafted hyaluronic acid(HA)induced supramolecular tethering and fusion of acidic vesicles via strong host-guest interactions between CB[7]of CB[7]-HA and ADA residing on the surface of acidic *** a proof-ofconcept,the overall cellular metabolism,including endogenous autophagy and the exogenous endocytosis and phagocytosis,was effectively upregulated,demonstrating that supramolecular regulation of the dynamics of intracellular acidic vesicles may promote the lysosome’s digestion to significantly improve cellular self-repair and self-defense.

关键词： supramolecular chemistry organelle regulation intracellular acidic vesicles lysosomes selfdefense self-repair

Insights into photocatalytic mechanism over a novel Cu_(2)WS_(4)/MoS_(2) S-scheme heterojunction

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Rare Metals 2024年第7期43卷 3118-3133页

作者： Wei Zhao Ji-Hui Cao Jun-Jie Liao Yun Liu Xiao-Jun Zeng Jun-Yu Shen Xue-Kun Hong Yang guo He-Hua Zeng Ya-zi Liu School of Materials Engineering Jiangsu Key Laboratory of Advanced Functional MaterialsSchool of Electronic and Information EngineeringChangshu Institute of TechnologyChangshu215500China School of Chemistry and Chemical Engineering Changji UniversityChangji 831100China State Environmental Protection Key Laboratory of Soil Environmental Management and Pollution Control Ministry of Ecology and EnvironmentNanjing Institute of Environmental SciencesNanjing 210023China School of Environment Jiangsu Engineering Lab of Water and Soil Eco-RemediationNanjing Normal UniversityNanjing 210023China Department of Chemical Engineering Curtin UniversityPerthWA6845Australia

A novel efficient Cu_(2)WS_(4)/MoS_(2) step-scheme(S-scheme)heterojunction photocatalyst was constructed for the first time and applied in the removal of environmental *** the as-prepared photocatalysts,the Cu_(2)WS_(4)/MoS_(2)-8%heterojunc tion photoc atalyst demonstrates the optimal photocatalytic performance,with the catalytic oxidation efficiency of tetracycline(TC)and the catalytic reduction efficiency of Cr^(6+)reaching 93.3%and 82.1%,*** excellent catalytic properties of Cu_(2)WS_(4)/MoS_(2) heterojunction photocatalysts are attributed to the effective separation pathways of charges and the presence of S-scheme heterojunctions,together with stronger redox *** is speculated that the photogenerated carrier migration path of the Cu_(2)WS_(4)/MoS_(2) catalyst follows the typical S-scheme photocatalytic mechanism,which is verified by the in-depth experimental study and simulated calculations including the electron paramagnetic resonance(EPR)analysis,free radical quenching experiments,charge density distribution,and simulated built-in electric field formation at the interface,which acts as driving force to promote the separation of photoinduced electrons and ***,the photocatalytic mechanism of S-scheme photogenerated carrier migration for the Cu_(2)WS_(4)/MoS_(2) catalyst is revealed based on the systematic experimental techniques and simulated calculations,accounting for its superior photocatalytic oxidation and reduction *** study provides inspiring implications to develop high-efficient S-scheme photocatalytic systems for versatile applications in solarenergy conversion.

关键词： Cu_(2)WS_(4)/MoS_(2) S-scheme Heterojunction Photocatalysis

Challenges and opportunities in the production of magnesium parts by directed energy deposition processes

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Journal of Magnesium and Alloys 2024年第5期12卷 1663-1686页

作者： gürel Cam Ali günen Iskenderun Technical University Faculty of Engineering and Natural SciencesDepartment of Mechanical Engineering31200 Iskenderun-HatayTurkey Iskenderun Technical University Faculty of Engineering and Natural SciencesDepartment of Metallurgy and Materials Engineering31200 Iskenderun-HatayTurkey

Mg-alloys have gained considerable attention in recent years for their outstanding properties such as lightweight,high specific strength,and corrosion resistance,making them attractive for applications in medical,aerospace,automotive,and other transport ***,their widespread application is hindered by their low formability at room temperature due to limited slip *** Mg-alloys have low mechanical properties due to the presence of casting defects such as porosity and anisotropy in addition to the high *** casting methods benefit from established process optimization techniques for these problems,additive manufacturing methods are increasingly replacing casting methods in Mg alloys as they provide more precise control over the microstructure and allow specific grain orientations,potentially enabling easier optimization of anisotropy properties in certain *** metal additive manufacturing(MAM)technology also results in some manufacturing defects such as inhomogeneous microstructural evolution and porosity and additively manufactured Mg alloy parts exhibit lower properties than the wrought parts,they in general exhibit superior properties than the cast ***,MAM is a promising technique to produce Mg alloy *** energy deposition processes,particularly wire arc directed energy deposition(wa-DED),have emerged as an advantageous additive manufacturing(AM)technique for metallic materials including magnesium alloys,offering advantages such as high deposition rates,improved material efficiency,and reduced production costs compared to subtractive ***,the inherent challenges associated with magnesium,such as its high reactivity and susceptibility to oxidation,pose unique hurdles in the application of this *** review paper delves into the progress made in the application of DED technology to Mg-alloys,its challenges,and ***,the predominant imperfections,notably inhomo

关键词： Additive manufacturing DED processes Arc-DED Wire arc additive manufacturing(waAM) 3-D printing High deposition rate

Cytospora pyri promotes Erwinia amylovora virulence by providing metabolites and hyphae

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Journal of Integrative Agriculture 2024年第9期23卷 3045-3054页

作者： tong Shen Mengdi Ye Yeping Xu Bohan Ding Hongtao Li Li Zhang Jun wa.g Yanli Tian Baishi Hu Youfu Zhao College of Plant Protection/Key Laboratory of Integrated Management of Crop Diseases and Pests Nanjing Agricultural UniversityNanjing 210095China Key Laboratory of Plant Quarantine Pests Monitoring and Control Ministry of Agriculture and Rural AffairsNanjing 210095China Plant Protection and Quarantine Station of Xinjiang Uygur Autonomous Region Urumqi 830001China Xinjiang Key Laboratory of Agricultural Biosafety Institute of Plant ProtectionXinjiang Academy of Agricultural SciencesUrumqi 830013China College of Agriculture Xinjiang Agricultural UniversityUrumqi 830052China Plant Pathology Department Washington State UniversityProsserWA 24106USA

Bacterial-fungal interactions are widespread in *** observed that pear orchards affected by Cytospora pyri(formerly Valsa pyri)were often accompanied with Erwinia ***,the relationship of the two pathogens was *** objective of this study was to determine whether the synergistic effect exists between *** and *** first analyzed the coexistence frequencies of *** and *** in pear *** of the two pathogens,growth,physical interactions,amylovoran production,and expression of genes for amylovoran biosynthesis were *** results showed that *** and *** could coexist on the same lesion and caused much more severe *** also found that *** could physically attach to *** and the expression of amylovoran biosynthesis genes were up-regulated with fungal metabolite *** results indicate that *** and *** can cooperatively interact,which provides *** with an opportunity to promote bacterial dispersal and production of virulence factor in ***.

关键词： pear fire blight Erwinia amylovora Valsa canker amylovoran synergy

Heavy Metal Remediation in AgoèNyivéLandfill Soils: Enhancing Stability through Organic Amendments

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Open Journal of Applied Sciences 2024年第4期14卷 961-975页

作者： Bassaï Magnoudéwa Bodjona Diyakadola Dihéénane Bafai gado Tchangbedji waste Management Treatment and Valorization Laboratory (GTVD) Faculty of Sciences University of Lom&#233 Lom&#233 Togo

The burial of waste in developing countries, which is often carried out without respect for environmental standards, constitutes a risk of contamination of soils and even groundwater given the toxic elements they contain. The objective of this work is to carry out a study of the retention of heavy metals through the contribution of cattle manure to soil samples from the final Agoè Nyivé landfill in Lomé, Togo. Soil samples from the final landfill were taken from the surface and depth at several locations to form a composite sample. The amendment of the composite sample was carried out with bovine manure on the mock-up in the Laboratory for six months. The determination of the total contents of heavy metals by the atomic absorption spectrophotometer (SAA) on the composite sample showed high contents exceeding the thresholds recommended by the AFNOR NF U 44-041 standard. Sequential extraction on these composite samples showed that the mobile portions of lead, cadmium, copper and zinc are respectively estimated at 78.06%, 50%, 28.89% and 91.59%. The bovine manure used to amend the landfill samples presents physicochemical parameters that can contribute to rendering heavy metals immobile in the soil matrix under natural conditions. The addition of manure initially made it possible to increase the values of pH, electrical conductivity, cation exchange capacity and organic matter, which promote the retention of heavy metals. Secondly, the addition of manure made it possible to reduce the mobile portion of the heavy metals studied;from 78.06% to 14.39% for lead, from 50% to 11.52% for cadmium, from 28.89% to almost 0% for copper and from 91.15% to 80.58% for zinc. The use of cattle manure as an amendment on the composite sample was decisive in reducing the mobility of heavy metals in the polluted soils of the final landfill.

关键词： Pollution Heavy Metals Soil Sequential Extraction Discharge

Physico-Chemical Characterization of Wood Ash for Agronomic Purposes

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Journal of Agricultural Chemistry and Environment 2024年第2期13卷 235-250页

作者： Ayi Kévin Ajavon Bassaï Magnoudéwa Bodjona Diyakadola Dihéénane Bafai Laboratory waste Management Treatment and Recovery (GTVD) Faculty of Sciences University of Lome Lome Togo

The oil refinery of the food products company SOPAL, located in the port area of TOgO, produces an average of 200 kg of eucalyptus wood ash per day. This ash is stored in large quantities within the premises of the refinery, without any disposal solution. The aim of this study is to identify the physico-chemical properties of SOPAL’s wood ash for agronomic valorization. Physico-chemical analyses reveal the presence of major and secondary elements such as potassium (15.71 g/kg DM), phosphorus (27.90 g/kg DM), calcium (9.76 g/kg DM), magnesium (0.03 g/kg DM), sodium (1.24 g/kg DM), iron (1.49 g/kg DM) and manganese (7.82 g/kg DM). The pH is alkaline (12.97) with fairly high conductivity (24.10 mS/Cm). Heavy metals identified are cobalt (0.19 mg/kg DM), cadmium (0.10 mg/kg DM), lead (1.14 mg/kg DM), copper (19.77 mg/kg DM) and nickel (12.82 mg/kg DM). The results show that the ash contains considerable amount of major and secondary elements for agronomic uses.

关键词： Industry Wood Ash Heavy Metals Valorization