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Tree-ring δ^(15)N of Qinghai spruce in the central Qilian Mountains of China:Is pre-treatment of wood samples necessary?

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Journal of Arid Land 2022年第6期14卷 673-690页

作者： WANG ziyi LIU Xiaohong WANG Keyi ZENG Xiaomin ZHANG Yu ge Wensen KANG Huhu LU Qiangqiang School of geography and Tourism Shaanxi Normal UniversityXi'an 710119China State Key Laboratory of Cryospheric Science Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China Qilian Mountain National Park Research Center(Qinghai) Xining 810008China School of Earth System Science Tianjin UniversityTianjin 300072China

A knowledge of the tree-ring stable nitrogen isotope ratio(δ^(15)N)can deepen our understanding of forest ecosystem dynamics by indicating the long-term availability,cycling and sources of nitrogen(N).However,the radial mobility of N blurs the interannual variations in the long-term N *** studies of the chemical extraction of tree rings before analysis had produced inconsistent results and it is still unclear whether it is necessary to pre-treat wood samples from specific tree species to remove soluble N compounds before determining theδ^(15)N *** compared the effects of pre-treatment with organic solvents and hot ultrapure water on the N concentration andδ^(15)N of tree rings from endemic Qinghai spruce(Picea crassifolia)growing in the interior of the central Qilian Mountains,China,during the last 60 *** assessed the effects of different preparation protocols on the removal of the labile N compounds and investigated the need to pre-treat wood samples before determining theδ^(15)N values of tree *** trends of the tree-ring N concentration were consistently observed in both the extracted and unextracted wood *** total N removed by extraction with organic solvents was about 17.60%,with a significantly higher amount in the sapwood section(P<0.01).Theδ^(15)N values of tree rings decreased consistently from 1960 to 2019 in both the extracted and unextracted wood *** with organic solvents increased theδ^(15)N values markedly by about 5.2‰and reduced the variations in theδ^(15)N ***,extraction with hot ultrapure water had little effect,with only a slight decrease in theδ^(15)N values of about 0.5‰.Our results showed that the radial pattern in the inter-ring movement of N in Qinghai spruce was not minimized by extraction with either organic solvents or hot ultrapure *** is unnecessary to conduct hot ultrapure water extraction for the wood samples from Qinghai spruce because of its negligible effect on t

关键词： tree rings stable nitrogen isotope ratio(δ^(15)N) nitrogen concentration solvent-extracted wood water-extracted wood wood pre-treatment Qinghai spruce Qilian Mountains

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Beamforming Optimization for RIS-Aided SWIPT in Cell-Free MIMO Networks

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China Communications 2021年第9期18卷 175-191页

作者： ziyi Yang Yu Zhang School of Information and Electronics Beijing Institute of TechnologyBeijing 100086China

Reconfigurable intelligent surface(RIS)is a promising technology that utilizes massive low-cost elements to reflect incident signals to desired *** this paper,we consider a RIS-aided cell free multiple-input multiple-output(MIMO)network that composed of multiple access points(APs),multiple RISs,multiple information receivers(IRs),and multiple energy receivers(ERs).Under the maximum transmit power constraints of the APs and the minimum total energy harvesting power constraints of the ERs,we aim to maximize the weighted sum-rate(WSR)by jointly optimizing the beamforming matrices and the passive RIS reflection ***,the formulated problem is nonconvex and very challenging to ***,we propose an alternating optimization algorithm to obtain a suboptimal ***,the proposed algorithm decomposes the original optimization problem into three subproblems that can be efficiently *** overcome the nonconvexity of the subproblems,a successive convex approximation(SCA)based algorithm is proposed to tackle the energy harvesting ***,an alternating direction method of multipliers(ADMM)based algorithm is proposed to optimize the constant modulus constrained RIS reflecting ***,simulations are conducted to demonstrate the performance advantages of the proposed algorithms.

关键词： cell-free networks SWIPT Reconfigurable intelligent surface SCA ADMM

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晚明灾疫应对中的基层政府运作——对万历十五年至十七年徽州府的考察

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古代文明（中英文） 2025年第1期19卷 128-141,M0007页

作者：葛俊超安徽师范大学历史学院安徽芜湖241000

地方政府的灾疫应对为观察基层治理结构的特殊案例。审视万历十五年至十七年南直隶徽州府灾疫:储备缺失与仓政废弛造成灾害破坏的持续释放,进而引发基层秩序紊乱。围绕资源的配置和获取,该府及所辖诸县积极与上级部门及周边地区政府进... 详细信息

地方政府的灾疫应对为观察基层治理结构的特殊案例。审视万历十五年至十七年南直隶徽州府灾疫:储备缺失与仓政废弛造成灾害破坏的持续释放,进而引发基层秩序紊乱。围绕资源的配置和获取,该府及所辖诸县积极与上级部门及周边地区政府进行互动。在自救无力、他救无望时,该府转而对域内社会力量进行全面动员,直接引导了基层社会的自我修复。该府的灾疫应对行为说明,在明朝晚期,基层政府仍在社会治理中扮演了主要角色。从灾疫处置视角切入基层社会,有助于走出“士绅社会”的定式思维,进一步丰富对帝制中国基层治理结构的认识。

关键词：晚明灾疫基层政府万历徽州

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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 WANG 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

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Homologous CoS2 interface with directed electron transfer and strong chloridion repulsion for efficient seawater oxidation

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Science China Chemistry 2025年

作者： Yuan Tian Jiang-Bo Chen Jie Ying ge Tian Yu-Xuan Xiao Yi Lu Si-Ming Wu Wei geng Ling Shen Xiao-Yu Yang State Key Laboratory of Advanced Technology for Materials Synthesis and Processing and School of Materials Science and Engineering and Shenzhen Research Institute & Laoshan Laboratory Wuhan University of Technology School of Chemical Engineering and Technology Sun Yat-Sen University National Energy Key Laboratory for New Hydrogen-Ammonia Energy Technologies Foshan Xianhu Laboratory

Seawater electrolysis is a highly promising method to produce high energy density hydrogen,especially in dry areas that have scarce freshwater ***,application of seawater electrolysis is confronted by two major problems associated with catalysts employed for the anodic oxygen evolution reaction （OER） including the competitive hypochlorite evolution reaction（HCER） and strong chloridion （Cl–） triggered *** studies aimed at overcoming these problems,a facile method has been developed to synthesize a homologous CoS2heterojunction as an OER *** to a difference in work functions at the interface and increased electron density,this material has directed electron transfer and strong chloridion repulsion properties,*** have shown that CoS2achieves low overpotentials of 289 and 322 mV at 10 mA cm-2current density in respective alkaline （1 M KOH） and alkaline simulated seawater ***,the outstanding stability of CoS2is reflected in a negligible decline in activity during promotion of the OER for 100 *** of density functional theory calculations reveal that the homologous CoS2heterojunction promotes directed electron transport for optimizing adsorption/desorption of reactive species and heightens the Cl-adsorption energy for strongly repulsing Cl-,phenomena that enhance OER performance in alkaline simulated seawater.

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Conditional Coverage Estimation for High-Quality Prediction Intervals

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Journal of Systems Science and Systems Engineering 2023年第3期32卷 289-319页

作者： ziyi Huang Henry Lam Haofeng Zhang School of Engineering and Applied Science Columbia UniversityNew YorkNY 10027USA

Deep learning has been recently studied to generate high-quality prediction intervals(PIs)for uncertainty quantification in regression tasks,including recent applications in simulation *** high-quality criterion requires PIs to be as narrow as possible,whilst maintaining a pre-specified level of data(marginal)***,most existing works for high-quality PIs lack accurate information on conditional coverage,which may cause unreliable predictions if it is significantly smaller than the marginal *** address this problem,we propose an end-to-end framework which could output high-quality PIs and simultaneously provide their conditional coverage *** doing so,we design a new loss function that is both easy-to-implement and theoretically justified via an exponential concentration *** evaluation on real-world benchmark datasets and synthetic examples shows that our approach not only achieves competitive results on high-quality PIs in terms of average PI width,but also accurately estimates conditional coverage information that is useful in assessing model uncertainty.

关键词： Uncertainty quantification prediction intervals conditional coverage neural networks calibrationerror

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创意写作的概念、原理及建制化发展——创意本体论创意写作学的基本主张及其建制实践

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当代文坛 2025年第1期 110-117页

作者：葛红兵马兵上海大学中国创意写作研究院

创意写作是一种创造性精神活动,以文字表达为实现形式,它遵循普遍的创意和表达规律,通过文化创意产业和事业来实现社会价值,助力“文化强国”和“创意国家”建设,依此而形成三大原理和创意生成叙事论、创意生成抒情论。中文创意写作学... 详细信息

创意写作是一种创造性精神活动,以文字表达为实现形式,它遵循普遍的创意和表达规律,通过文化创意产业和事业来实现社会价值,助力“文化强国”和“创意国家”建设,依此而形成三大原理和创意生成叙事论、创意生成抒情论。中文创意写作学的发展进入建制化时期,需要在基本概念和三大原理指引下,理论联系实际,平衡传承与创新、改革与接续的关系,自觉地承担中文学科改革者、探索者的角色,从培养目标、培养内容、培养方法等各个方面,改革中文学科旧制,走新建制主义之路。中文创意写作学科的工作者需要与种种错误的见解和窄化的庸见作斗争,突破传统中国汉语言文学学科的陈腐陋见。

关键词：创意写作叙事叙事生成-转换语法生成叙事转换叙事

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Advanced Functional Electromagnetic Shielding Materials:A Review Based on Micro‑Nano Structure Interface Control of Biomass Cell Walls

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Nano-Micro Letters 2025年第1期17卷 98-134页

作者： Yang Shi Mingjun Wu Shengbo ge Jianzhang Li Anoud Saud Alshammari Jing Luo Mohammed A.Amin Hua Qiu Jinxuan Jiang Yazeed M.Asiri Runzhou Huang Hua Hou Zeinhom M.El‑Bahy Zhanhu Guo Chong Jia Kaimeng Xu Xiangmeng Chen Co‑Innovation Center of Efficient Processing and Utilization of Forest Resources College of Materials Science and EngineeringNanjing Forestry UniversityNanjing 210037People’s Republic of China State Key Laboratory of Efficient Production of Forest Resourced Beijing Forestry UniversityQinghua East Road 35Haidian DistrictBeijing 100083People’s Republic of China Department of Physics Faculty of Sciences‑ArarNorthern Border UniversityArar 91431Saudi Arabia Department of Chemistry College of ScienceTaif UniversityP.O.Box 1109921944 TaifSaudi Arabia Shaanxi Key Laboratory of Macromolecular Science and Technology School of Chemistry and Chemical EngineeringNorthwestern Polytechnical UniversityXi’anShaanxi 710072People’s Republic of China Integrated Composites Lab Department of Mechanical and Construction EngineeringNorthumbria UniversityNewcastle Upon Tyne NE18STUK College of Materials Science and Engineering Taiyuan University of Science and TechnologyTaiyuan 030024People’s Republic of China Department of Chemistry Faculty of ScienceAl-Azhar UniversityNasr CityCairo 11884Egypt Yunnan Provincial Key Laboratory of Wood Adhesives and Glued Products International Joint Research Center for Biomass MaterialsSouthwest Forestry UniversityKunming 650224People’s Republic of China School of Science Henan Agricultural UniversityZhengzhou 450002People’s Republic of China

Research efforts on electromagnetic interference(EMI)shielding materials have begun to converge on green and sustainable biomass *** materials offer numerous advantages such as being lightweight,porous,and *** to their porous nature,interfacial compatibility,and electrical conductivity,biomass materials hold significant potential as EMI shielding *** concerted efforts on the EMI shielding of biomass materials have been reported,this research area is still relatively new compared to traditional EMI shielding *** particular,a more comprehensive study and summary of the factors influencing biomass EMI shielding materials including the pore structure adjustment,preparation process,and micro-control would be *** preparation methods and characteristics of wood,bamboo,cellulose and lignin in EMI shielding field are critically discussed in this paper,and similar biomass EMI materials are summarized and *** composite methods and fillers of various biomass materials were *** paper also highlights the mechanism of EMI shielding as well as existing prospects and challenges for development trends in this field.

关键词： Biomass materials Electromagnetic interference shielding Micro-nano structure interface control Conductivity

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Experimental investigation on uniaxial cyclic plasticity of cast AZ91 magnesium alloy

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Journal of Magnesium and Alloys 2023年第9期11卷 3255-3271页

作者： Yu Lei ziyi Wang Guozheng Kang Applied Mechanics and Structure Safety Key Laboratory of Sichuan Province School of Mechanics and Aerospace EngineeringSouthwest Jiaotong UniversityChengdu 610031China

The uniaxial cyclic plasticity of cast AZ91 magnesium(Mg) alloy was investigated by conducting a series of cyclic straining and stressing tests at room temperature, and a unique cyclic plasticity(especially for ratchetting) and its physical nature were revealed. The experimental results demonstrate that the cast AZ91 Mg alloy behaviors tension-compression symmetry, because the dislocation slipping and twinning occur during both the tensile and compressive deformations;although the cast AZ91 alloy presents a certain pseudo-elastic behavior during unloading due to the detwinning, there is no obvious S-shaped asymmetric hysteresis loop like that of wrought Mg alloy in the cyclic tensile-compressive tests, and an obvious cyclic hardening is observed;moreover, the ratchetting of the cast AZ91 alloy presented in the cyclic stressing tests depends remarkably on the prescribed mean stress and stress amplitude, but slightly changes with the stress rate, and the evolution of responding peak/valley strain greatly differs from that of wrought Mg alloys and stainless steels. This work provides rich experimental data for establishing the constitutive model of cast Mg alloys.

关键词： Cast magnesium alloy Ratchetting Twinning/detwinning Stress level Stress rate

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Continuous high-temperature rapid nanomanufacturing of electrocatalysts

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Nano Research 2025年第1期18卷 225-235页

作者： Xiaoyang Wang ziyi Luo Baihua Cui Ziqi Fu Yanchang Liu Weidi Liu Jia Ding Jianrong Zeng Yanan ChenWenbin Hu School of Materials Science and Engineering Tianjin UniversityTianjin 300350China Australian Institute for Bioengineering and Nanotechnology The University of QueenslandSt.LuciaBrisbane 4072Australia Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China

Encapsulating metal nanoparticles in carbon shells(Metal@C)to enhance catalytic activity and stability has been certified ***,most existing methods for preparing Metal@C are complex,time-consuming,and lack of *** this study,a novel method that couples the high-temperature shock(HTS)with ultrasonic spray pyrolysis is reported,which can realize facile and scalable production of various Metal@C through the pyrolysis of glucose and metal chloride *** proposed HTS ultrasonic spray pyrolysis offers several advantages,including compact size,short reaction time(~120 ms),and uniform *** the Ni@C-40 nanocomposite as an example,the ultrasmall Ni nanoparticles(~10 nm)with thin carbon protective shells(~2 nm)are uniformly dispersed in the carbon matrix and applied for oxygen evolution reaction(OER)in alkaline *** Ni@C-40 optimized by tuning the thickness of carbon shell exhibits significantly enhanced OER activity with low overpotential of 242 mV at 10 mA·cm^(-2) and stability,which is attributed to the optimized interactions between Ni nanoparticles and carbon *** method also shows promise for continuous pyrolysis synthesis of various extreme materials at ultra-high temperatures using alternative electric heating materials.

关键词： ultrasonic spray pyrolysis high-temperature shock carbon shell oxygen evolution reaction Metal@C nanocomposite

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