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International Journal of Minerals,Metallurgy and Materials 2024年第10期31卷 2233-2243页

作者： Guonan Ma Shize Zhu Dong Wang Peng Xue bolüXiao Zongyi Ma Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Centre of Excellence for Advanced Materials Dongguan 523808China

A high-zinc composite,12vol%SiC/Al-13.3 Zn-3.27 Mg-1.07Cu(wt%),with an ultra-high-strength of 781 MPa was success-fully fabricated through a powder metallurgy method,followed by an extrusion *** effects of solid-solution and aging heat treat-ments on the microstructure and mechanical properties of the composite were extensively *** with a single-stage sol-id-solution treatment,a two-stage solid-solution treatment(470℃/1 h+480℃/1 h)exhibited a more effective solid-solution strengthen-ing owing to the higher degree of solid-solution and a more uniform *** to the aging hardness curves of the com-posite,the optimized aging parameter(100℃/22 h)was *** the aging temperature and time resulted in finer and more uniform nanoscale precipitates but only yielded a marginal increase in tensile *** fractography analysis revealed that intergranu-lar cracking and interface debonding were the main fracture mechanisms in the ultra-high-strength SiC/Al-Zn-Mg-Cu *** regions,such as the SiC/Al interface containing numerous compounds and the precipitate-free zones at the high-angle grain boundaries,were identified as significant factors limiting the strength enhancement of the *** compounds,including MgO,MgZn2,and Cu5Zn8,reduced the interfacial bonding strength,leading to interfacial debonding.

关键词： metal matrix composites heat treatment interfacial reaction mechanical properties fracture mechanism

Interdigitated terahertz metamaterial sensors:design with the dielectric perturbation theory

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Photonics research 2024年第6期12卷 1115-1128页

作者： LEI CAO FANQI MENG ESrAÖZDEMIr YANNIK LOTH MErLE rICHTEr ANNA KATHArINA WIGGEr MAIrA BEATrIZ PÉrEZ SOSA ALAA JABBAr JUMAAH SHIHAB AL-DAFFAIE PETEr HArING bolÍVAr HArTMUT G.rOSKOS State Key Laboratory of Advanced Electromagnetic Technology Huazhong University of Science and TechnologyWuhan 430074China Physikalisches Institut Johann Wolfgang Goethe-UniversitätFrankfurt am MainGermany University of Siegen Institute for High Frequency and Quantum ElectronicsSiegenGermany Department of Electrical Engineering Eindhoven University of Technology5612 AE EindhovenThe Netherlands

Designing terahertz sensors for highly sensitive detection of nanoscale thin films and a few biomolecules poses a substantial challenge but is crucial for unlocking their full potential in scientific research and advanced *** work presents a strategy for optimizing metamaterial sensors in detecting small quantities of dielectric *** amount of frequency shift depends on intrinsic properties(electric field distribution,Q-factor,and mode volume)of the bare cavity as well as the overlap volume of its high-electric-field zone(s)and the *** by the simplified dielectric perturbation theory,interdigitated electric split-ring resonators(ID-eSrrs)are devised to significantly enhance the detection sensitivity compared with eSrrs without interdigitated ***-eSrr’s fin-gers redistribute the electric field,creating strongly localized enhancements,which boost analyte *** periodic change of the inherent antiphase electric field reduces radiation loss,leading to a higher *** with ID-eSrr sensors operating at around 300 GHz demonstrate a remarkable 33.5 GHz frequency shift upon depositing a 150 nm SiO_(2)layer as an analyte simulant,with a figure of merit improvement of over 50 times compared with structures without interdigitated *** rational design offers a promising avenue for highly sensitive detection of thin films and trace biomolecules.

关键词： dielectric perturbation theory

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基于光学相机的光流-相机定标融合定位算法

北京邮电大学学报 2024年第1期47卷 100-105,119页

作者：苑振博白勃罗柳君张晓薇尚韬西安电子科技大学通信工程学院西安710071

为了解决光流算法在相机大转角情况下定位误差过大和相机定标定位算法在LED数量不足的情况下无法定位的问题,提出将相机定标定位算法和光流算法进行卡尔曼滤波融合的光流-相机定标融合定位算法。首先,采用相机定标定位算法进行室内定位... 详细信息

为了解决光流算法在相机大转角情况下定位误差过大和相机定标定位算法在LED数量不足的情况下无法定位的问题,提出将相机定标定位算法和光流算法进行卡尔曼滤波融合的光流-相机定标融合定位算法。首先,采用相机定标定位算法进行室内定位;其次,引入光流算法补偿相机定标定位算法的计算结果;最后,采用卡尔曼滤波融合2种算法的定位结果。搭建实验平台验证所提算法的定位性能。实验结果表明,所提算法能够解决相机定标定位算法在LED数量不足的情况下无法定位的问题,同时能够克服光流算法在相机大转角情况下定位误差过大的问题,将相机在大转角运动情况下平均定位误差从6.86 cm降低至1.02 cm。

关键词：相机定标定位算法光流算法卡尔曼滤波准确性鲁棒性

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水氮耦合对枸杞冠层结构及产量的影响

节水灌溉 2024年第7期 24-32页

作者：王彦军马波管恩晴杨艳宁夏大学土木与水利工程学院银川750021 宁夏节水灌溉与水资源调控工程技术研究中心银川750021 教育部旱区现代农业水资源高效利用工程研究中心银川750021

为探明水氮耦合对枸杞冠层结构及产量的影响,揭示枸杞冠层结构与蒸散、氮消耗的互馈机制,于2014-2015年以4 a树龄的“宁杞1号”为研究对象,设置4个水平灌溉定额(W1:2277 m^(3)/hm^(2)、W2:2593 m^(3)/hm^(2)、W3:2856 m^(3)/hm^(2)及W4:... 详细信息

为探明水氮耦合对枸杞冠层结构及产量的影响,揭示枸杞冠层结构与蒸散、氮消耗的互馈机制,于2014-2015年以4 a树龄的“宁杞1号”为研究对象,设置4个水平灌溉定额(W1:2277 m^(3)/hm^(2)、W2:2593 m^(3)/hm^(2)、W3:2856 m^(3)/hm^(2)及W4:3160 m^(3)/hm^(2))及3个水平施氮量(2014年N1:501 kg/hm^(2)、N2:668 kg/hm^(2)及N3:860 kg/hm^(2);2015年N1:620 kg/hm^(2)、N2:854 kg/hm^(2)及N3:1092 kg/hm^(2)),对比分析不同水、氮条件对枸杞冠层结构及产量的影响。结果表明:2 a均表明W3N2处理枸杞叶面积指数(LAI)和平均叶倾角(MTA)较大,其中LAI为2.46(2014年)和2.86(2015年),较其他处理(除2015年W2N1外)提高了2.9%~80.1%(2014年)和4.7%~48.9%(2015年),MTA为45°(2014年)和50°(2015年),较其他处理增加了7.1%~40.6%(2014年)和6.4%~28.2%(2015年),该处理透射率(DIFN)在各处理中居中,介于0.25~0.35;2 a试验结果均W3N2处理产量最高,分别为2599.9 kg/hm^(2)(2014)和4621.7 kg/hm^(2)(2015),与其他处理相比提高了42.5%~65.7%(2014)和0.5%~15.9%(2015);蒸散量(ET_(a))随LAI和MTA增加而增加,但LAI超过3时,就会抑制冠层蒸散;LAI趋于3、MTA和DIFN分别介于45°~50°和0.25~0.35时,枸杞碱解氮消耗较大,2014年和2015年分别为883.4 kg/hm^(2)和1001.1 kg/hm^(2)。综合分析,在枸杞理想冠层和最大产量目标下,灌溉定额为2856 m^(3)/hm^(2),4 a树龄施氮量为668 kg/hm^(2),5 a树龄施氮量为854 kg/hm^(2),有利于枸杞冠层结构生长发育且会获得理想的产量,研究结果可为宁夏枸杞水肥管理及冠层结构调整提供理论依据。

关键词：水氮耦合枸杞冠层结构耗水过程产量蒸散量

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Investigation on Superplasticity in SiC_p/2024 Cold rolling Sheet after Heat Treatment

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Journal of Materials Science & Technology 2003年第4期19卷 382-384页

作者： bolüXIAO ZongyiMA JingBI InstituteofMetalresearch ChineseAcademyofSciencesShenyang110016China DepartmentofMetallurgicalEngineering UniversityofMissouriRollaRollaMO65401USA

High strain rate superplastic deformation behavior of powder metallurgy (PM) processed 17 vol. pet SiCp/2024 Al composite sheet after heat treatment was investigated over a range of temperature from 753 to 833 K. At 813 K, a maximum elongation of 259% was discovered at a strain rate of 10-1 s-1. The activation energy was closed to that for lattice diffusion of Al and increased at temperature upon incipient melting temperature. The mechanism of superplastic deformation for present composites was attributed to lattice diffusion controlled grain boundary sliding.

关键词： Superplasticity Powder metallurgy Metai matrix composites

Digestive and breast cancer patients managed during the first wave of COVID-19 pandemic:Short and middle term outcomes

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World Journal of Methodology 2024年第2期14卷 107-126页

作者： Jacobo Tr.bol Ana Carabias-Orgaz María Carmen Esteban-Velasco Asunción García-Plaza Juan Ignacio González-Munoz Ana Belén Sánchez-Casado Felipe Carlos Parreno-Manchado Marta Eguía-Larrea José Antonio Alcázar-Montero Cirugía General y del Aparato Digestivo Complejo Asistencial Universitario de SalamancaSalamanca 37007SalamancaSpain Cirugía Universidad de SalamancaSalamanca 37007SalamancaSpain Oftalmología Complejo Asistencial Universitario de SalamancaSalamanca 37007SalamancaSpain

BACKGrOUND The first wave of coronavirus disease 2019(COVID-19)pandemic in Spain lasted from middle March to the end of June *** population was subjected to lockdown periods and scheduled surgeries were discontinued or reduced during variable *** our centre,we managed patients previously and newly diagnosed with *** established a strategy based on limiting perioperative social contacts,preoperative screening(symptoms and reverse transcriptionpolymerase chain reaction)and creating separated in-hospital COVID-19-free pathways for non-infected *** also adopted some practice modifications(surgery in different facilities,changes in staff and guidelines,using continuously changing personal protective equipment…),that supposed new *** To analyse cancer patients with a decision for surgery managed during the first wave,focalizing on outcomes and pandemic-related *** We prospectively included adults with a confirmed diagnosis of colorectal,oesophago-gastric,liver-pancreatic or breast cancer with a decision for surgery,regardless of whether they ultimately underwent *** analysed short-term outcomes[30-d postoperative morbimortality and severe acute respiratory syndrome coronavirus 2(SArS-CoV-2)infection]and outcomes after 3 years(adjuvant therapies,oncological events,death,SArS-CoV-2 infection and vaccination).We also investigated modifications to usual *** From 96 included patients,seven didn’t receive treatment that period and four never(3 due to COVID-19).Operated patients:28 colon and 21 rectal cancers;laparoscopy 53.6%/90.0%,mortality 3.57%/0%,major complications 7.04%/25.00%,anastomotic leaks 0%/5.00%,3-years disease-free survival(DFS)82.14%/52.4%and overall survival(OS)78.57%/76.2%.Six liver metastases and six pancreatic cancers:no mortality,one major complication,three grade A/B liver failures,one bile leak;3-year DFS 0%/33.3%and OS 50.0%/33.3%(liver metastases/pancreatic carcinoma).5 g

关键词： COVID-19 SArS-CoV-2 Colon cancer rectal cancer Breast cancer Liver cancer Pancreatic cancer Gastric cancer Oesophageal cancer Surgery

Soil organic matter amendments in date palm groves of the Middle Eastern and North African region:a mini-review

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Journal of Arid Land 2016年第1期8卷 77-92页

作者： rawan MLIH roland bol Wulf AMELUNG Nadhem BrAHIM Institute of Bio-Geoscience Agrosphere Institute (IBG-3) Juelich Research Center Institute of Crop Science and resource Conservation (INrES)/Soil Science and Soil Ecology University of Bonn Faculty of Sciences of Tunis Department of Geology University of Tunis El Manar

Countries in the Middle Eastern and North African (MENA) region are among the most water-scarce regions in the world, and their dryland soils are usually poor in organic carbon content (rize examples of how people in the few oases of the MENA region overcome environmental challenges by sustainably managing economically important date production. On the basis of the limited studies found in the existing literature, this mini-review focuses on the role of traditional soil organic matter amendments beneath the soil surface as a key tool in land restoration. We conclude that soil organic matter amendments can be very successful in restoring soil water and preventing the soil from salinization.

关键词： review Middle Eastern and North African (MENA) drylands organic matter amendments oasis agrosystem date palm production

High responsivity and Ultra-Low Detection Limits in Nonlinear a-Si:H p-i-n Photodiodes Enabled by Photogating

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Photonic Sensors 2023年第4期13卷 27-38页

作者： Andreas BABLICH Maurice MÜLLEr rainer BOrNEMANN Andreas NACHTIGAL Peter HArING bolÍVAr Institute of Graphene-Based Nanotechnology University of SiegenHölderlinstr.357076 SiegenGermany Institute of High Frequency and Quantum Electronics University of SiegenHölderlinstr.357076 SiegenGermany

Photodetectors operating at the wavelength in the visible spectrum are key components in high-performance optoelectronic *** this work,massive nonlinearities in amorphous silicon p-i-n photodiodes enabled by the photogating are presented,resulting in responsivities up to 744 mA/W at blue *** detectors exhibit significant responsivity gains at optical modulation frequencies exceeding MHz and a more than 60-fold enhanced spectral response compared to the non-gated *** detection limits down to 10.4 nW/mm^(2) and mean signal-to-noise ratio enhancements of 8.5dB are demonstrated by illuminating the sensor with an additional 6.6μW/mm^(2) red ***-optical simulations verify photocarrier modulation due to defect-induced field screening to be the origin of such high responsivity *** experimental results validate the theory and enable the development of commercially viable and complementary metal oxide semiconductor(CMOS)compatible high responsivity photodetectors operating in the visible range for low-light level imaging and detection.

关键词： Photogating amorphous silicon a-Si:H nonlinearity photodetector responsivity gain

The Current Status and Future Prospects of Forest Certification in Myanmar

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The Current Status and Future Prospects of Forest Certificat...

作者： Ei Thandar.bol 北京林业大学

学位级别：硕士

Myanmar had been practicing Sustainable Forest Management since1856. Although Myanmar had a long history in Forest Management, Myanmar does not have internationally recognized certification standard, such as FSC or PEFC. To get Forest Certification is the goal of our Sustainable Forest Management. Nowadays Myanmar faces preparation for potential negotiations with the European Union, ASEAN’s agreement and international organizations in the field of sustainable forest management. The main purpose of this study is that to explore about Forest Certification in Myanmar. In this thesis the researcher tries to analyze the level of Myanmar Forest Certification progress, to identify the key elements for the development and implementation of timber legality in Myanmar by using qualitative research methodology. Myanmar has started Timber Certification process in1988and achieved to some extent. However, it needs to go a long way especially to comply with the standards （C＆I） for the forest management certification. The analysis will also deal with the real situation of forest certification in Myanmar and also try to base on the COCs of timber legality tracking system, market functionality, status of C＆I, policy and remedial measure. It is concluded and argued in this thesis it evident that Myanmar is in a pioneer stage of forest certification and moved the topic on the national level. According to the management systems an adaptation of biodiversity conservation practices, rIL, Code of Forest Harvesting, Community Forest Instructions and Timber Legality Assurance System are some major achievements.

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Wear behavior of the raw and pre-smashed carbon nanotubes reinforced 6061Al composites fabricated by powder metallurgy

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Science China(Technological Sciences) 2022年第5期65卷 1149-1159页

作者： LI XiaoNan LIU ZhenYu ZAN YuNing XIAO bolü NI Dingrui WANG QuanZhao WANG Dong MA ZongYi Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang110016China

The raw and pre-smashed(PS)carbon nanotube(CNT)reinforced 6061Al composites(CNT/6061Al)with different CNT contents were respectively fabricated by powder metallurgy *** was found that reducing the CNT cluster size by presmashing processing could sharply reduce the friction coefficient,and significantly improve the density,hardness,and wear resistance of the CNT/6061Al *** the raw-CNT/6061Al composites,the wear rate increased approximately linear trend while the CNT content was over 1 wt.%.The plastic deformation,deep grooves,and serious delamination were presented on the wear *** wear process was gradually transformed from Al-copper base counterpart wear into Al-Al wear for the higher adhesion-binding energy between aluminum and copper base *** for the PS-CNT/6061Al composites,the wear rate gradually decreased as the CNT content increased from 0 to 2 wt.%.This was mainly because the generation of the thinner mechanically mixed layer(MML)and the PS-CNT prevented the direct contact between specimen and copper base counterpart,which effectively inhibited the adhesive *** excessive PS-CNTaddition(~3 wt.%)would weaken the bonding between CNT and 6061Al,and thus the wear resistance of the composite was reduced apparently.

关键词： wear carbon nanotube aluminum matrix composites clustering