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Metallurgical performance evaluation of space-weathered Chang’e-5 lunar soil

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International Journal of minerals,Metallurgy and materials 2024年第6期31卷 1241-1248页

作者： Chen Li Wenhui ma Yang Li Kuixian Wei Center for Lunar and Planetary Sciences Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China Faculty of Metallurgical and Energy Engineering Kunming University of Science and TechnologyKunming 650093China

Space metallurgy is an interdisciplinary field that combines planetary space science and metallurgical *** involves systematic and theoretical engineering technology for utilizing planetary resources in ***,space metallurgy on the Moon is challenging because the lunar surface has experienced space weathering due to the lack of atmosphere and magnetic field,making the mi-crostructure of lunar soil differ from that of minerals on the *** this study,scanning electron microscopy and transmission electron microscopy analyses were performed on Chang’e-5 powder lunar soil *** microstructural characteristics of the lunar soil may drastically change its metallurgical *** main special structure of lunar soil minerals include the nanophase iron formed by the impact of micrometeorites,the amorphous layer caused by solar wind injection,and radiation tracks modified by high-energy particle rays inside mineral *** nanophase iron presents a wide distribution,which may have a great impact on the electromagnetic prop-erties of lunar *** ions injected by solar wind may promote the hydrogen reduction *** widely distributed amorph-ous layer and impact glass can promote the melting and diffusion process of lunar ***,although high-energy events on the lun-ar surface transform the lunar soil,they also increase the chemical activity of the lunar *** is a property that earth samples and tradi-tional simulated lunar soil *** application of space metallurgy requires comprehensive consideration of the unique physical and chemical properties of lunar soil.

关键词： space metallurgy Chang’e-5 lunar soil space weathering metallurgical performance

Accurate Analysis of Multi-Mode Interferometric optical Fiber Sensor

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Photonic Sensors 2024年第1期14卷 48-58页

作者： Lijun LI Congying JIA Qian ma Tianzong XU College of Electronic and Information Engineering Shandong University of Science and TechnologyQingdao 266590.China State Key Laboratory of Mining Disaster Prevention and Control Co-Founded by Shandong Province and the Ministry of Science and Technology Qingdao 266590China

In view of the problem that the sensing characteristics of the multi-mode interferometric fiber sensors cannot be accurately analyzed,an analysis method based on the fast Fourier transform(FFT)and inverse fast Fourier transform(IFFT)is proposed and demonstrated theoretically and *** suitabilities of the rectangular window function with the narrow main lobe(high spectrum resolution)and low side lobe(high main mode energy leakage)and the Hanning window function with the wide main lobe(low spectrum resolution)and high side lobe(high energy concentration)in this kind of sensor analysis are discussed,*** method can not only realize the sensing performance analysis of the various modes,but also overcome the inconsistency of the different interference wavelength(dip)sensing characteristics in the conventional analysis *** the same time,this method is also beneficial to solve the repetitive problem of such sensors.

关键词： Window function FFT optical fiber interferometric sensor analysis method

Diagnostic performance of dynamic contrast-enhanced magnetic resonance imaging parameters and serum tumor markers in rectal carcinoma prognosis

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World Journal of Gastrointestinal oncology 2024年第5期16卷 1796-1807页

作者： Ren-Qi Mu Jun-Wei Lv Cai-Yun ma Xiao-Hui ma Dong Xing Hou-Sheng ma Department of Radiology Yantai Mountain HospitalYantai 264001Shandong ProvinceChina Department of Radiology Yantai Yuhuangding HospitalYantai 264000Shandong ProvinceChina Department of Gynaecology Yantai Yuhuangding HospitalYantai 264000Shandong ProvinceChina The First Clinical Medical College Xinjiang Medical UniversityUrumqi 830011Xinjiang Uygur Autonomous RegionChina

BACKGRoUND Rectal carcinoma(RC),one of the most common malignancies globally,presents an increasing incidence and mortality year by year,especially among young people,which seriously affects the prognosis and quality of life of *** present,dynamic contrast-enhanced magnetic resonance imaging(DCE-MRI)parameters and serum carbohydrate antigen 19-9(CA19-9)and CA125 Levels have been used in clinical practice to evaluate the T stage and differentiation of ***,the accuracy of these evaluation modalities still needs further *** study explores the application and value of these methods in evaluating the T stage and differentiation degree of *** To analyze the diagnostic performance of DCE-MRI parameters combined with serum tumor markers(TMs)in assessing pathological processes and prognosis of RC *** A retrospective analysis was performed on 104 RC patients treated at Yantai Yuhuangding Hospital from may 2018 to January *** were categorized into stages T1,T2,T3,and T4,depending on their T stage and differentiation *** addition,they were assigned to low(L group)and moderate-high differentiation(M+H group)groups based on their differentiation *** levels of DCE-MRI parameters and serum CA19-9 and CA125 in different groups of patients were *** addition,the value of DCE-MRI parameters[volume transfer constant(Ktrans),rate constant(Kep),and extravascular extracellular volume fraction(Ve)in assessing the differentiation and T staging of RC patients was ***,the usefulness of DCE-MRI parameters combined with serum CA19-9 and CA125 Levels in the evaluation of RC differentiation and T staging was *** Ktrans,Ve,CA19-9 and CA125 were higher in the high-stage group and L group than in the low-stage group and M+H Group,respectively(Pof the Ktran and Ve parameters were 0.638 and 0.694 in the diagnosis of high and low stages,respectively,and 0.672 and 0

关键词： Rectal carcinoma Volume transfer constant Rate constant Extravascular extracellular volume fraction Serum carbohydrate antigen 19-9 Serum carbohydrate antigen 125

Key points and visible part fusion attention network for occluded pedestrian detection in traffic environments

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optoelectronics Letters 2024年第7期20卷 430-436页

作者： LIU Peiyu ma Yixuan School of Software Engineering Beijing Jiaotong University

Aiming at the problem of low detection accuracy of occluded pedestrian in traffic environments,this paper proposes a key points and visible part fusion network for occluded pedestrian *** proposed algorithm constructs two attention modules by introducing human key points and the bounding box of visible parts respectively,which suppresses the occluded parts in the channel features and spatial features of pedestrian features *** results on CityPersons and Caltech datasets demonstrate the effectiveness of the proposed *** missing rate(MR) is reduced to 40.78 on the Heavy subset of the CityPersons dataset and surpasses many outstanding methods.

关键词： A

3D simulation of image-defined complex internal features using the numerical manifold method

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Science China(Technological Sciences) 2024年第4期67卷 1023-1039页

作者： WU Jie ma GuoWei School of Civil and Transportation Engineering Hebei University of TechnologyTianjin 300401China Tianjin Key Laboratory for Prefabricated Building and Intelligent Construction Tianjin 300401China

The numerical simulation of internal features,such as inclusions and voids,is important to analyze their impact on the performance of composite ***,the complex geometries of internal features and the induced continuous-discontinuous(C-D)deformation fields are challenges to their numerical *** this study,a 3D approach using a simple mesh to simulate irregular internal geometries is developed for the first *** the help of a developed voxel crack model,image models that are efficient when recording complex geometries are directly imported into the *** reconstructions,which are usually labor-intensive,are excluded from this ***,using image models as the geometric input,image processing techniques are applied to detect material interfaces and develop contact ***,the C-D deformations of the complex internal features are directly calculated based on the numerical manifold *** accuracy and convergence of the developed3D approach are examined based on multiple *** 3D C-D simulation of sandstones with naturally formed complex microfeatures demonstrates the capability of the developed approach.

关键词： 3D continuous-discontinuous simulation image-based simulation complex internal features numerical manifold method voxel crack model structured mesh

Unravelling the nature of the active species as well as the Mn doping effect over gamma-Al_(2)o_(3) catalyst for eliminating AsH_(3) and PH_(3)

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Journal of Environmental Sciences 2024年第2期136卷 213-225页

作者： Bowen Xu Jiaxin Qu Xueqian Wang Langlang Wang Yu Pu Ping Ning Yibing Xie Yixing ma Qiang ma Faculty of Environmental Science and Engineering Kunming University of Science and TechnologyKunming 650500China School of Architecture and Civil Engineering Chengdu UniversityChengdu 610106China

To investigate the enhancing effect of Mn on the performance of simultaneous catalytic oxidation of AsH_(3)and PH_(3)by Cuo-Al_(2)o_(3)in a reducing atmosphere under micro-oxygen conditions,Cu-Mn modifiedγ-Al_(2)o_(3)catalysts were *** characteristics of the catalysts showed that Mn reduced the crystallinity of the active Cuo component,increased the number of oxygen vacancies and acidic sites on the catalyst surface,enhanced the mobility of surface oxygen,and the interaction between copper and manganese promoted the redox cycling ability of the catalysts and improved their oxidation performance,which increased the conversion frequency(ToF)by 2.54×10^(-2)to 3.07×10^(-2)sec^(-1).on the other hand,the introduction of Mn reduced the production of phosphate and As_(2)o_(3)on the catalyst surface by30.96%and 44.9%,which reduced the coverage and inerting of the active sites by phosphate and As_(2)o_(3),resulting in an 8 hr(6 hr)improvement in the stability of PH_(3)(AsH_(3))removal.

关键词： AsH_(3)-PH_(3)removal oxygen activation Mn doping Stability enhancement

Growth,optical dispersion and magnetic behavior of Dy^(3+) doped yttrium iron garnet crystals

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Journal of Rare Earths 2024年第6期42卷 1110-1117,I0004页

作者： Yating Fang Hui Shen Yudie ma Shijie Liao Shuang Xia Tian Tian Ding Zhou Yunfeng ma Jiayue Xu Institute of Crystal Growth School of Materials Science and EngineeringShanghai Institute of Technology National Engineering Center of Electromagnetic Radiation Control materials School of Electronic Science and EngineeringUniversity of Electronic Science and Technology of China

Y_(3)Fe_(5)o_(12)(YIG)crystals are highly desirable for the fabrication of mid-infrared isolators with the rapid growth of optical communications,although it is rather challenging to grow large size and high-quality single ***^(3+)doping is expected to improve the optical and magneto-optical prope ***,high quality Dy:YIG crystals and the adjustment of Dy^(3+)on the structure and optical behavior of YIG crystal remain unclear,impeding its practical ***,a series of Y_(3-x)Dy_(x)Fe_(5)o_(12)(x=0,0.5,1.0,1.5,3)solid solution crystals was grown by the flux-Bridgman method and single crystals up to 25 mm were *** the introduction of Dy^(3+),lattice parameters are gradually enlarged from 1.2379 nm(YIG)to 1.2420 nm(DyIG).Typical Dy^(3+)absorption peaks are observed around 1070,1265 and 1670 *** refractive index decreases from 2.37(500 nm)to 2.10(2500 nm)for YIG crystal,and it reduces from 2.47(500 nm)to 2.16(2500 nm)for DyIG *** optical bandgaps remain almost unchanged for Dy:YIG *** optical dispersion of the refractive indices was finely fitted by the Wemple and DiDomenico(WDD)and the Sellmeier models,*** the increase of Dy^(3+)content,the saturation magnetization(Ms)decreases significantly from 23.62 emu/g(YIG)to 5.33 emu/g(DyIG).Small coercive field is persisted for this system,endowing small external magnetic *** results provide valuable references for the manipulation of rare earths on the properties of magnetooptical crystals,which is beneficial to the design of high-performance garnet crystals for the application of optical switching and non-reciprocal related devices.

关键词： magneto-optical crystal Yttrium iron garnet Dy^(3+)doping Crystal growth optical dispersion Rare earths

Night warming increases wheat yield by improving pre-anthesis plant growth and post-anthesis grain starch biosynthesis

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Journal of Integrative Agriculture 2024年第2期23卷 536-550页

作者： Yonghui Fan Boya Qin Jinhao Yang Liangliang ma Guoji Cui Wei He Yu Tang Wenjing Zhang Shangyu ma Chuanxi ma Zhenglai Huang College of Agronomy Anhui Agricultural University/Key Laboratory of Wheat Biology and Genetic Improvement in South Yellow&Huai River ValleyMinistry of Agriculture and Rural AffairsHefei 230036China Xianyang Central Station for Agricultural Technology Extension Xianyang 712000China

Global climate change is characterized by asymmetric warming,i.e.,greater temperature increases in winter,spring,and nighttime than in summer,autumn,and *** experiments were conducted using four wheat cultivars,namely‘Yangmai 18’(YM18),‘Sumai 188’(SM188),‘Yannong 19’(YN19),and‘Annong 0711’(AN0711),in the two growing seasons of 2019-2020 and 2020-2021,with passive night warming during different periods in the early growth *** treatments were night warming during the tillering-jointing(NW_(T-J)),jointing-booting(NWJ-B),and booting-anthesis(NWB-A)stages,with ambient temperature(NN)as the *** effects of night warming during different stages on wheat yield formation were investigated by determining the characteristics of dry matter accumulation and translocation,as well as sucrose and starch accumulation in wheat *** wheat yields of all four cultivars were significantly higher in NW_(T-J)than in NN in the 2-year *** yield increases of semi-winter cultivars YN19 and AN0711 were greater than those of spring cultivars YM18 and *** NW_(T-J)increased wheat yield mainly by increasing the 1,000-grain weight and the number of fertile spikelets,and it increased dry matter accumulation in various organs of wheat at the anthesis and maturity stages by increasing the growth rate at the vegetative growth *** flag leaf and spike showed the largest increases in dry matter ***_(T-J)also increased the grain sucrose and starch contents in the early and middle grain-filling stages,promoting yield ***,night warming between the tillering and jointing stages increased the pre-anthesis growth rate,and thus,wheat dry matter production,which contributed to an increase in wheat yield.

关键词： wheat asymmetric warming dry matter accumulation and translocation starch yield

Interfacial tribochemical kinetics: A new perspective on superlubricity of diamond-like carbon films

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Science China(Technological Sciences) 2024年第7期67卷 2050-2052页

作者： CHEN WeiQi ma Tian-Bao State Key Laboratory of Tribology in Advanced Equipment Tsinghua UniversityBeijing 100084China

Friction is considered one of the primary challenges affecting the performance of machine operations and is a significant source of energy loss in industrial applications. About 30%of disposable energy is consumed by ... 详细信息

关键词： kinetics friction operations

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