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Geology and Geochemistry of K-feldspar Veins in Lamprophyre at the Zhenyuan Gold Deposit,Yunnan,Southwest China:Implications for Gold Mineralization

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Acta Geologica Sinica(English Edition) 2024年第1期98卷 104-116页

作者： ZHANG Huichao CHAI Peng ZHANG Hongrui Zhou Limin hou Zengqian Key Laboratory of Submarine Geosciences Second Institute of OceanographyMinistry of Natural ResourcesHangzhou 310012China Institute of Geology Chinese Academy of Geological SciencesBeijing 100037China Key Laboratory of Marine Hazards Forecasting Ministry of Natural ResourcesHohai UniversityNanjing 210024China National Research Center for Geoanalysis Beijing 100037China

Lamprophyres typically appear in hydrothermal gold *** relationship between lamprophyres and gold deposits is investigated *** researchers suggest that the emplacement of lamprophyres triggers gold mineralization,whereas others hypothesize that the formation of lamprophyres increases the fertility of mantle sources and ore-forming fluids.K-feldspar veins,with ages between those of lamprophyres and gold deposits,appear in lamprophyres in ***,K-feldspar veins are ideal for investigating the relationship between lamprophyres and gold *** in K-feldspar veins has lower Mg#,Ni,and Cr contents and higher TiO2,Li,Ba,Sr,Sc,Zr,Nb,and Cs contents than phlogopite in *** in-situ Sr isotopic values of apatites(0.7063–0.7066)in K-feldspar veins are within the range for apatites(0.7064–0.7078)from *** large-ion lithophile element concentrations and low Nb and Ta concentrations in phlogopite from lamprophyres,in addition to high(87Sr/86Sr)i values of apatite(0.7064–0.7078),indicate that the magma parental to these phlogopite and apatite crystals is derived from an enriched *** veins are genetically correlated with lamprophyres,whereas sulfide mineral assemblage and trace element compositions of pyrite in K-feldspar veins suggest that K-feldspar veins in lamprophyres are not directly related to gold mineralization of the Zhenyuan deposit.

关键词： lamprophyre K-feldspar vein apatite Sr isotope gold Zhenyuan deposit Yunnan

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Modeling and Performance Analysis of UAV-Aided Millimeter Wave Cellular Networks with Stochastic Geometry

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China Communications 2024年第6期21卷 146-162页

作者： Li Junruo Wang Yuanjie Cui Qimei hou Yanzhao Tao Xiaofeng National Engineering Laboratory for Mobile Network Technologies Beijing University of Posts and TelecommunicationsBeijing 100876China National Computer Network Emergency Response Technical Team/Coordination Center of China(CNCERT/CC) Beijing 100029China Department of Broadband Communication Peng Cheng LaboratoryShenzhen 518055China

UAV-aided cellular networks,millimeter wave(mm-wave) communications and multi-antenna techniques are viewed as promising components of the solution for beyond-5G(B5G) and even 6G *** leveraging the power of stochastic geometry,this paper aims at providing an effective framework for modeling and analyzing a UAV-aided heterogeneous cellular network,where the terrestrial base stations(TBSs) and the UAV base stations(UBSs) coexist,and the UBSs are provided with mm-wave and multi-antenna *** modeling the TBSs as a PPP and the UBSs as a Matern hard-core point process of type Ⅱ(MPH-Ⅱ),approximated but accurate analytical results for the average rate of the typical user of both tiers are derived through an approximation method based on the mean interference-to-signal ratio(MISR) *** influence of some relevant parameters is discussed in detail,and some insights into the network deployment and optimization are *** results show that some trade-offs are worthy of being considered,such as the antenna array size,the altitude of the UAVs and the power control factor of the UBSs.

关键词： average rate downlink millimeter wave point process theory SIR stochastic geometry UAVaided cellular networks

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Porous high-entropy rare-earth phosphate(REPO_(4),RE=La,Sm,Eu,Ce,Pr and Gd)ceramics with excellent thermal insulation performance via pore structure tailoring

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International Journal of Minerals,Metallurgy and Materials 2024年第7期31卷 1651-1658页

作者： Peixiong Zhang Enhui Wang Jingjing Liu Tao Yang Hailong Wang Xinmei hou Institute for Carbon Neutrality University of Science and Technology BeijingBeijing 100083China Liaoning Academy of Materials Shenyang 110000China Technical Support Center for Prevention and Control of Disastrous Accidents in Metal Smelting University of Science and Technology BeijingBeijing 100083China School of Materials Science Engineering Zhengzhou UniversityZhengzhou 450001China

Thermal insulation materials play an increasingly important role in protecting mechanical parts functioning at high *** this study,a new porous high-entropy(La_(1/6)Ce_(1/6)Pr_(1/6)Sm_(1/6)Eu_(1/6)Gd_(1/6))PO_(4)(HE(6RE_(1/6))PO_(4))ceramics was prepared by combining the high-entropy method with the pore-forming agent method and the effect of different starch contents(0–60vol%)on this ceramic properties was systematically *** results show that the porous HE(6RE_(1/6))PO_(4)ceramics with 60vol%starch exhibit the lowest thermal conductivity of 0.061 W·m^(-1)·K^(-1)at room temperature and good pore structure stability with a linear shrinkage of approximately1.67%.Moreover,the effect of large regular spherical pores(>10μm)on its thermal insulation performance was discussed,and an optimal thermal conductivity prediction model was *** superior properties of the prepared porous HE(6RE_(1/6))PO_(4)ceramics allow them to be promising insulation materials in the future.

关键词： porous high-entropy(La_(1/6)Ce_(1/6)Pr_(1/6)Sm_(1/6)Eu_(1/6)Gd_(1/6))PO_(4) ceramics high-entropy strategy pore-forming agent method thermal insulation material thermal conductivity

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空心岩样径向渗流-轴向应力特征与巷道围岩渗透突变机理

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煤炭学报 2022年第3期47卷 1180-1195页

作者：马丹侯文涛张吉雄王佳军李振华杜锋中国矿业大学矿业工程学院江苏徐州221116 中国矿业大学煤炭资源与安全开采国家重点实验室江苏徐州221116 中国矿业大学深部煤炭资源开采教育部重点实验室江苏徐州221116 中南大学资源与安全工程学院湖南长沙410083 河南理工大学能源科学与工程学院河南焦作454000

为了探究承压水下巷道围岩的渗透突变机理,针对空心岩样的渗流-应力特征开展了一系列室内试验和渗透突变表征模型研究。自主研制了一套空心岩样径向渗流-轴向应力试验系统,突破了仅开展轴向渗流的传统试验条件限制,实现了径向渗流及轴... 详细信息

为了探究承压水下巷道围岩的渗透突变机理,针对空心岩样的渗流-应力特征开展了一系列室内试验和渗透突变表征模型研究。自主研制了一套空心岩样径向渗流-轴向应力试验系统,突破了仅开展轴向渗流的传统试验条件限制,实现了径向渗流及轴向应力同步进行。采用该新型试验系统,以孔径(5~20 mm)和水压(0.5~2.5 MPa)为变量开展多组空心红砂岩渗流-应力试验,得到空心岩样径向渗流-轴向应力特征。试验结果表明径向渗流的蚀损作用引起岩样黏聚力、内摩擦角等力学参数衰减,增大水压,渗流的蚀损作用变强,岩样内部裂隙贯通通道形成时间缩短,渗透突变现象提前发生。大孔径岩样对轴向应力敏感度更高,内部结构受径向渗流蚀损作用易破坏,渗透突变发生时间缩短。岩样渗透率在试验过程中存在3种状态:①以孔隙结构为主要渗流介质的孔隙渗流状态;②以局部裂隙结构为主要渗流介质的非稳定渗流状态;③以贯通裂隙结构为主要渗流介质的渗透突变状态。渗透率达到峰值的试样渗流介质为受水压影响产生的贯通裂隙结构,峰值渗透率随水压增大呈线性增长,与孔径没有明显关系。以裂隙体积变化为纽带建立空心岩样渗透突变表征模型,模型计算值与实验结果吻合良好。以屈服应力/应变、峰值应力/应变为临界条件将渗透率演化曲线分为3个阶段:①渗透率微增演化阶段;②渗透率突增演化阶段;③峰后渗透率演化阶段。其中,渗透率突增演化阶段是突水灾害发生的控制环节,需在此之前采取注浆封堵、输水降压等措施预防事故发生。

关键词：渗透突变空心试样径向渗流渗透率演变蚀损作用

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Research on Improved MobileViT Image Tamper Localization Model

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Computers, Materials & Continua 2024年第8期80卷 3173-3192页

作者： Jingtao Sun Fengling Zhang Huanqi Liu Wenyan hou School of Computer Science and Technology Xi’an University of Posts and TelecommunicationsXi’an710121China Shaanxi Key Laboratory of Network Data Analysis and Intelligent Processing Xi’an University of Posts and TelecommunicationsXi’an710121China

As image manipulation technology advances rapidly,the malicious use of image tampering has alarmingly escalated,posing a significant threat to social *** the realm of image tampering localization,accurately localizing limited samples,multiple types,and various sizes of regions remains a multitude of *** issues impede the model’s universality and generalization capability and detrimentally affect its *** tackle these issues,we propose FL-MobileViT-an improved MobileViT model devised for image tampering *** proposed model utilizes a dual-stream architecture that independently processes the RGB and noise domain,and captures richer traces of tampering through dual-stream ***,the model incorporating the Focused Linear Attention mechanism within the lightweight network(MobileViT).This substitution significantly diminishes computational complexity and resolves homogeneity problems associated with traditional Transformer attention mechanisms,enhancing feature extraction diversity and improving the model’s localization *** comprehensively fuse the generated results from both feature extractors,we introduce the ASPP architecture for multi-scale feature *** facilitates a more precise localization of tampered regions of various ***,to bolster the model’s generalization ability,we adopt a contrastive learning method and devise a joint optimization training strategy that leverages fused features and captures the disparities in feature distribution in tampered *** strategy enables the learning of contrastive loss at various stages of the feature extractor and employs it as an additional constraint condition in conjunction with cross-entropy *** a result,overfitting issues are effectively alleviated,and the differentiation between tampered and untampered regions is *** evaluations on five benchmark datasets(IMD-20,CASIA,NIST-16,Columbia and Coverage)validat

关键词： Image tampering localization focused linear attention mechanism MobileViT contrastive loss

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An Approximation Algorithm for the Parallel-Machine Customer Order Scheduling with Delivery Time and Submodular Rejection Penalties

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Journal of the Operations Research Society of China 2024年第2期12卷 495-504页

作者： Hong-Ye Zheng Suo-Gang Gao Wen Liu Bo hou School of Mathematical Sciences Hebei Normal UniversityShijiazhuang 050024HebeiChina

In this paper,we consider the parallel-machine customer order scheduling with delivery time and submodular rejection *** this problem,we are given m dedicated machines in parallel and n customer *** order has a delivery time and consists of m product types and each product type should be manufactured on a dedicated *** order is either rejected,in which case a rejection penalty has to be paid,or accepted and manufactured on the m dedicated *** objective is to find a solution to minimize the sum of the maximum delivery completion time of the accepted orders and the penalty of the rejected orders which is determined by a submodular *** design an LP rounding algorithm with approximation ratio of n+1 for this problem.

关键词： Order scheduling Delivery time-Submodular rejection penalty:Approximationalgorithm

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GmNF-YC4 delays soybean flowering and maturation by directly repressing GmFT2a and GmFT5a expression

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Journal of Integrative Plant Biology 2024年第7期66卷 1370-1384页

作者： Yupeng Cai Li Chen Xiaoqian Liu Weiwei Yao Wensheng hou State Key Laboratory of Crop Gene Resources and Breeding Institute of Crop SciencesChinese Academy of Agricultural SciencesBeijing 100081China Ministry of Agriculture Key Laboratory of Soybean Biology(Beijing) Institute of Crop SciencesChinese Academy of Agricultural SciencesBeijing 100081China

Flowering time and growth period are key agronomic traits which directly affect soybean(Glycine max(L.)Merr.)adaptation to diverse latitudes and farming *** FLOWERING LOCUS T(FT)homologs GmFT2a and GmFT5a integrate multiple flowering regulation pathways and significantly advance flowering and maturity in *** the genes responsible for regulating GmFT2a and GmFT5a will improve our understanding of the molecular mechanisms governing growth period in *** this study,we identified the Nuclear Factor Y-C(NFY-C)protein GmNF-YC4 as a novel flowering suppressor in soybean under long-day(LD)***-YC4 delays flowering and maturation by directly repressing the expression of GmFT2a and *** addition,we found that a strong selective sweep event occurred in the chromosomal region harboring the GmNF-YC4 gene during soybean *** GmNF-YC4Hap3 allele was mainly found in wild soybean(Glycine soja Siebold&Zucc.)and has been eliminated from *** landraces and improved cultivars,which predominantly contain the GmNF-YC4Hap1 ***,the Gmnf-yc4 mutants displayed notably accelerated flowering and maturation under LD *** alleles may prove to be valuable genetic resources for enhancing soybean adaptability to higher latitudes.

关键词： CRISPR/Cas9 early flowering and maturity GmNF-YC4 regional adaptability soybean

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Re-delocalization of localized d-electrons in VO_(2)(R)-VS_(4)hetero-structure enables high performance of rechargeable Mg-ion batteries

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Journal of Magnesium and Alloys 2024年第5期12卷 1830-1840页

作者： Lijiao Zhou Chao Shen Xueyang hou Zhao Fang Ting Jin Keyu Xie School of Materials Science and Engineering Northwestern Polytechnical UniversityXi’an 710072China School of Metallurgical Engineering Xi’an University of Architecture and TechnologyXi’an 710055China

Rechargeable Mg-ion batteries(MIBs)have attracted much more attentions by virtue of the high capacity from the two electrons ***,the reversible Mg^(2+)diffusion in cathode materials is restricted by the strong interactions between the high-polarized bivalent Mg^(2+)ions and anionic ***,we design and propose a hetero-structural VO_(2)(R)-VS_(4)cathode,in which the re-delocalized d-electrons can effectively shield the polarity of Mg^(2+)***,the electrons should spontaneously transfer from VS_(4)to VO_(2)(R)through the interfaces of hetero-structure due to the lower work function value of VS_(4).Furthermore,the internal electrons transfer lead to the electronic injection into VO_(2)(R)from VS_(4)and the partially broken V-V dimers,indicating the presence of lone pair electrons and charge *** from the shield effect of re-delocalized electrons,and the weakened attraction between cations and O/S anions enables more S^(2-)-S_(2)^(2-)redox groups to participate the electrochemical reactions and compensate the double charge of Mg^(2+)***,VO_(2)(R)-VS_(4)hetero-structure exhibits a high specific capacity of 554 mA h g^(-1)at 50 mA g^(-1).It is believed that the charge re-delocalization of cathode extremely boost the Mg^(2+)ions migration for the high-capacity of MIBs.

关键词： Mg-ion batteries Cathode Charge delocalization Electronic structure Heterostructure

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Dual Frequency Transformer for Efficient SDR-to-HDR Translation

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Machine Intelligence Research 2024年第3期21卷 538-548页

作者： Gang Xu Qibin hou Ming-Ming Cheng Tianjin Media Computing Center College of Computer ScienceNankai UniversityTianjin300000China

The SDR-to-HDR translation technique can convert the abundant standard-dynamic-range (SDR) media resources to high-dynamic-range (HDR) ones, which can represent high-contrast scenes, providing more realistic visual experiences. While recent vision Transformers have achieved promising performance in many low-level vision tasks, there are few works attempting to leverage Transformers for SDR-to-HDR translation. In this paper, we are among the first to investigate the performance of Transformers for SDR-to-HDR translation. We find that directly using the self-attention mechanism may involve artifacts in the results due to the inappropriate way to model long-range dependencies between the low-frequency and high-frequency components. Taking this into account, we advance the self-attention mechanism and present a dual frequency attention (DFA), which leverages the self-attention mechanism to separately encode the low-frequency structural information and high-frequency detail information. Based on the proposed DFA, we further design a multi-scale feature fusion network, named dual frequency Transformer (DFT), for efficient SDR-to-HDR translation. Extensive experiments on the HDRTV1K dataset demonstrate that our DFT can achieve better quantitative and qualitative performance than the recent state-of-the-art methods. The code of our DFT is made publicly available at https://***/CS-GangXu/DFT.

关键词： Standard-dynamic-range to high-dynamic-range(SDR-to-HDR)translation Transformer dual frequency attention(DFA) frequency-aware feature decomposition efficient model

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Revealing effect of Al content on oxidation of novel Co-Cr-Nb-W carbide-strengthened superalloy

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Rare Metals 2024年第9期43卷 4521-4534页

作者： Chen Ling Shang-Ping Li Jie hou He-Li Luo Central Iron & Steel Research Institute Beijing GAONA Materials&Technology Co. Ltd.

The high-temperature oxidation behavior of novel Co-Cr-Nb-W carbide-strengthened wear-resistance alloys with different Al contents（1wt%, 2wt% and 3wt%）at 950, 1000 and 1050 °C was thoroughly investigated by scanning electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy and field emission electron probe analyzer. The porous property of Nb C in-situ oxidation products（Nb2O5, Co Nb2O6and Co4Nb2O9） induces a multi-layered oxide scale with micropores and ***-Cr-Nb-W alloy with 1 wt% Al undergoes catastrophic oxidation and spalling above 1000 °C. The outward transportation of Cr and Co is effectively restrained by a continuous Al2O3scale formed around Nb C in-situ oxidation region when Al content reaches 3 wt%. The β-Co Al in Co-Cr-Nb-W alloy with 3 wt% Al has an oxidation priority over eutectic carbides and the alloy matrix which are both enriched with Cr, thereby preventing the formation of Cr-depletion area and improving the self-healing ability of the oxide film. A slight change in Al content has a remarkable influence on the cooperative effect of Al and Cr and multiplies the antioxidant capacity of Co-Cr-Nb-W alloy above 1000 °C.

关键词： High-temperature oxidation behavior Microstructure Oxidation kinetics Superalloy Wear-resistant alloy

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