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The earliest evidence f.r 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 f.und 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 theref.re 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 f.irly typical microblade technological orientation and two types of.microblade cores:wedge-shaped and semi-conical,which are similar to those f.und throughout North *** Optically Stimulated Luminescence(OSL)dating and AMS^(14)C dating,the age of.ND3 ranges f.om 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 inf.rmation 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 f.rst prolonged human occupation of.the plateau and that microblades played a signif.cant role in mediating the risks and f.cilitating 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

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Strengthening and control of.second-phase particle precipitation in f.rritic/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-f.ng 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 f.elds,and f.rther improvement in their properties is essential to meet the requirements in new-generation advanced supercritical boilers,nuclear reactors,superheaters,and other new materials *** ef.ectively enhance the comprehensive perf.rmance of.heat-resistant alloys,second-phase particle strengthening has been widely studied,and in the f.ce of.dif.erent service envi-ronments of.advanced heat-resistant steels,the selection of.suitable second-phase particles is essential to maximize the perf.rmance of.these *** this end,three major types of.reinf.rcing 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 reinf.rcing phases with dif.erent types as well as the risks and means of.controlling their use in service,is *** parameters f.r the application of.various types of.second-phase particles in heat-resistant alloys are provided to support the design and preparation of.new ultrahigh-perf.rmance 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-f.cing material,is subjected to high f.uence 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 unif.rm damage prof.le similar to neutron irradiation,carbon(C) ions with multiple energies and angles were *** samples were f.rther irradiated with low-energy D ions under two f.uences at temperatures f.om ～380 to 640 *** various experimental techniques,we f.und that pre-damaged W samples can ef.ectively suppress the f.rmation of.blistering and lower the threshold temperature at which the surf.ce remains f.ee 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 f.sion reactors could increase the critical D concentration f.r blistering,while a greater depth of.damage f.cilitated the inward dif.usion of.D,thereby reducing the D concentration gradient and alleviating surf.ce 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.Def.nse

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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-f. 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 f.r self.repair and self.def.nse upon f.sion with endosomes,autophagosomes,and ***,artif.cially manipulating intracellular vesicles could potentially promote lysosome-mediated intracellular digestion f.r disease prevention and ***,a supramolecular strategy to ef.iciently tether and f.se acidic vesicles(i.e.,lysosomes,late endosomes,autolysosomes,and phagosomes)has been developed f.r the f.rst time to enhance the digestion of.cellular wastes and f.reign 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 surf.ces with ***,the addition of.cucurbit[7]uril(CB[7])graf.ed hyaluronic acid(HA)induced supramolecular tethering and f.sion of.acidic vesicles via strong host-guest interactions between CB[7]of.CB[7]-HA and ADA residing on the surf.ce of.acidic *** a proof.of.oncept,the overall cellular metabolism,including endogenous autophagy and the exogenous endocytosis and phagocytosis,was ef.ectively upregulated,demonstrating that supramolecular regulation of.the dynamics of.intracellular acidic vesicles may promote the lysosome’s digestion to signif.cantly improve cellular self.repair and self.def.nse.

关键词： supramolecular chemistry organelle regulation intracellular acidic vesicles lysosomes self.ef.nse self.repair

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 f.r their outstanding properties such as lightweight,high specif.c strength,and corrosion resistance,making them attractive f.r applications in medical,aerospace,automotive,and other transport ***,their widespread application is hindered by their low f.rmability at room temperature due to limited slip *** Mg-alloys have low mechanical properties due to the presence of.casting def.cts such as porosity and anisotropy in addition to the high *** casting methods benef.t f.om established process optimization techniques f.r these problems,additive manuf.cturing methods are increasingly replacing casting methods in Mg alloys as they provide more precise control over the microstructure and allow specif.c grain orientations,potentially enabling easier optimization of.anisotropy properties in certain *** metal additive manuf.cturing(MAM)technology also results in some manuf.cturing def.cts such as inhomogeneous microstructural evolution and porosity and additively manuf.ctured 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 manuf.cturing(AM)technique f.r metallic materials including magnesium alloys,of.ering advantages such as high deposition rates,improved material ef.iciency,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 imperf.ctions,notably inhomo

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

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Heavy Metal Remediation in AgoèNyivéLandf.ll 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 Baf.i 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 of.en carried out without respect f.r 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 f.om the f.nal Agoè Nyivé landf.ll in Lomé, Togo. Soil samples f.om the f.nal landf.ll were taken f.om the surf.ce and depth at several locations to f.rm a composite sample. The amendment of.the composite sample was carried out with bovine manure on the mock-up in the Laboratory f.r 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 Af.OR 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 landf.ll 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;f.om 78.06% to 14.39% f.r lead, f.om 50% to 11.52% f.r cadmium, f.om 28.89% to almost 0% f.r copper and f.om 91.15% to 80.58% f.r 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 f.nal landf.ll.

关键词： Pollution Heavy Metals Soil Sequential Extraction Discharge

Physico-Chemical Characterization of.Wood Ash f.r 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 Baf.i Laboratory waste Management Treatment and Recovery (GTVD) Faculty of Sciences University of Lome Lome Togo

The oil ref.nery of.the f.od 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 ref.nery, without any disposal solution. The aim of.this study is to identif. the physico-chemical properties of.SOPAL’s wood ash f.r 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 f.irly high conductivity (24.10 mS/Cm). Heavy metals identif.ed 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 f.r agronomic uses.

关键词： Industry Wood Ash Heavy Metals Valorization

Comprehensive Overview of.Populus simonii Research in the Recent Years

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Open Journal of.Ecology 2024年第5期14卷 419-434页

作者： Dandan Zhang f.ujiah Nurhasanah Ritonga Tuya Siqin Runxian Song Zicheng Zhang Mingwei Tang Peilin Sun wa.gao Heilongjiang Institute of.Atomic Energy Harbin China graduate School Padjadjaran University Bandung Indonesia Key Laboratory of.Molecular Epigenetics of.the Ministry of.Education Northeast Normal University Changchun China

As an important ecological tree species in northern China, Populus simonii plays a crucial role in maintaining ecological balance and promoting environmental sustainability. The academic community has conducted a series of.in-depth studies on this species, covering key areas such as genomics, survival mechanisms, and genetic breeding. Through the analysis of.the genomic structure and f.nction of.P. simonii, we have not only revealed the molecular basis f.r its adaptation to harsh environments but also identif.ed key genes that promote its growth and resistance to pests and diseases. f.rthermore, exploring the survival mechanisms of.P. simonii has deepened our understanding of.its stress resistance traits, including how it ef.ectively copes with abiotic stresses such as drought, salinization, and heavy metal pollution. In genetic breeding, signif.cant progress has been made through the application of.modern biotechnology, improving the growth rate and wood quality of.P. simonii and enhancing its environmental adaptability and disease resistance. These research f.ndings have not only enriched our knowledge of.the biological characteristics of.P. simonii but also provided a solid scientif.c f.undation f.r its application in ecological restoration, f.restry production, and environmental management.

关键词： Breeding Ecological Restoration genomics Populus simonii Resistance Mechanisms

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玉米野生种基因组研究进展及应用

生物技术通报 2024年第3期40卷 14-24页

作者：胡伊娃陈露浙江大学农业与生物技术学院作物科学研究所杭州310058

气候变化为粮食生产、生态系统的稳定性带来了重要的挑战。在极端气候变化下,发展适应性物种是作物遗传育种的重要目标之一。作为重要的作物之一,玉米在经历强烈的驯化瓶颈之后,已经丢失了大量的遗传多样性,特别是一些与生物和非生物胁... 详细信息

气候变化为粮食生产、生态系统的稳定性带来了重要的挑战。在极端气候变化下,发展适应性物种是作物遗传育种的重要目标之一。作为重要的作物之一,玉米在经历强烈的驯化瓶颈之后,已经丢失了大量的遗传多样性,特别是一些与生物和非生物胁迫相关的位点。在野生种和农家种中寻找玉米驯化过程中丢失的遗传多样性,并将其应用于现代遗传育种中,将为适应性新品种的创制提供新的契机。本文在对大刍草(玉米野生近亲)的发现及分类研究进行介绍之后,进一步总结了大刍草和玉米的性状与基因组差异,并综述了目前基于遗传学、群体遗传学、分子生物学等对大刍草和玉米之间差异遗传机理剖析的进展,多角度表明了大刍草在玉米遗传学研究中的重要性。最后,对未来气候变化下大刍草在玉米育种中的重要性提出了展望。

关键词：气候变化玉米适应性野生种

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