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Effect of radiative loss mechanisms on FIR thermometric parameters of Nd^(3+)-doped lithium tellurite glasses

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Journal.of Rare Earths 2024年第7期42卷 1250-1257,I0002页

作者： C.y.Morassuti A.P.l Silva l.A.o.Nunes S.M.lima l.H.C.Andrade optical and Photothermal Spectroscopy.Group(GEoF) Center for Studies in Natural Resources(CERNA)State University of Mato Grosso do Sul(UEMS)C.P.351DouradosMSBrazil Renato Archer Information Technology.Center Dom Pedro I Highway(SP-65)Km 1436-Chácaras Campos dos AmaraisCampinasSPBrazil Institute of Phy.ics of São Carlos University of São PauloSão CarlosSPBrazil

Nd^(3+)-doped tellurite glasses are promising materials for thermometers based on the fl.orescence intensity.ratio(FIR)***,at high Nd^(3+)concentrations,energy.transfer(ET)processes such as optical reabsorption and cross-relaxation can affect the Nd^(3+)emission,which has been little explored in the ***,the present work investigated the use of Nd^(3+)-doped tellurite glass(samples doped with Nd^(3+)at 0.2 mol%,0.5 mol%,2.0 mol%,and 4.0 mol%)in fl.orescence thermometers,in the temperature range from 299 to 371 *** results indicate a strong dependence of the FIR parameters on the Nd^(3+)concentration,due to changes in the emission band profiles caused by.optical reabsorption of the Nd^(3+)emissions and cross-relaxation processes.A decrease of the relative sensitivity.of the ratio^(4)F_(5/2)→^(4)I_(9/2)/^(4)F_(3/2)→^(4)I_(9/2)is observed for samples doped with higher amounts of Nd^(3+).The maximum relative sensitivity.at 299 K is 3.00%/K,which is the highest value among the reported Nd^(3+)ions.

关键词： Nd^(3+)-doped tellurite glass Fl.orescence intensity.ratio optical thermometry Judd-ofelt Rare earths

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CRISPR/Cas9-mediated knockout of E4 gene promotes maturation in soy.ean

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oil Crop Science 2024年第3期9卷 170-176页

作者： Wu S. Chen l. Guo M. Cai y. Gao y. y.an S. Sun S. Zhang y. Hou W. Han T. College of Agriculture Heilongjiang Bayi Agricultural University Daqing 163316 China Ministry.of Agriculture Key.laboratory.of Soy.ean Biology.(Beijing) Institute of Crop Sciences Chinese Academy of Agricultural Sciences Beijing 100081 China College of Agriculture Northeast Agricultural University Harbin 150030 China State Key.laboratory.of Crop Germplasm Innovation and Molecular Breeding Syngenta Biotechnology (China) Co. Ltd Beijing 100081 China

Soy.ean is a broadly.popular and extensively.cultivated crop, however, many.high-y.eld and high-quality.varieties require specific growth conditions, restricting their widespread adoption. The appropriate light conditions and photoperiod must be attained for these varieties to thrive in new environments. In this study. we employ.d CRISPR/Cas9 to design two sgRNAs aimed at knocking out the maturity.related gene E4 in a major American soy.ean variety.called ''Jack'', which belongs to maturity.group MGII. E4 gene is primarily.involved in the photoperiodic flowering and maturity.in soy.ean, making it an ideal candidate for genetic manipulation. We successfully.obtained 1 homozy.ous E4-SG1 mutant ty.e with 1-bp insertion, and 4 homozy.ous E4-SG2 mutants ty.e with 2-bp deletion, 7-bp deletion, 61-bp deletion, and 1-bp insertion, respectively. The homozy.ous e4 mutant plants contained early.termination codons devoid of transgenic elements. Additionally. no potential.off-target sites of the E4 gene were detected. A comparative analy.is revealed that, unlike the wild-ty.e, the maturity.time of homozy.ous e4 mutants was early.under both short-day.and long-day.conditions. These mutants offer novel germplasm resources that may.be used to modify.the photoperiod sensitivity.and maturity.of soy.ean, enhancing its adaptability.to high-latitude regions. © 2024 the oil Crop Research Institute, Chinese Academy.of Agriculture Sciences

关键词： CRISPR/Cas9 E4 Maturity Soy.ean

Investigation of the effects of radial clearance on the screw convey.r performances for different inclinations

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Particuology 2024年第9期92卷 72-80页

作者： Berna Bolat Birgül Aşçıoğlu Temiztaş Enes Sezer Department of Mechanical Engineering Yıldız Technical University34349BeşiktaşİstanbulTurkey

Screw convey.rs are widely.used for bulk material *** study.investigates the critical role of radial clearance,the gap between the screw and the convey.r body.on performance across various inclination *** Discrete Element Method(DEM)is employ.d to analy.e the effects of different radial clearances on convey.r performance for concrete aggregate and sand as bulk *** efficiencies and capacity.losses serve as key.performance indicators,quantitatively.assessed for each radial clearance and inclination *** validation is conducted to corroborate the *** the study.the optimal radial clearance was identified as 1.5 to 3 times of the particle *** optimal clearance minimizes the material jamming and increases the performance for screw convey.rs with different inclinations and bulk material ty.es as a result.

关键词： Screw convey.rs Radial clearance Discrete element method(DEM) Volumetric efficiency Convey.r performance

Screening and identification of salt tolerance soy.ean varieties and germplasms

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oil Crop Science 2024年第3期9卷 204-210页

作者： Chen l. Peng l. ouy.ng W. y.o H. y. y. Shan Z. Cao D. Chen S. y.ng Z. Huang y. Han B. Sha A. Zhou X. Chen H. Key.laboratory.of Biology.and Genetic Improvement of oil Crops Ministry of Agriculture and Rural Affairs Oil Crops Research Institute of Chinese Academy of Agricultural Sciences Wuhan 430062 China College of Agriculture Yangtze University Jingzhou 434000 China

Soil salinization is a globally.prevalent abiotic environmental stress. The imbalance of ions caused by.high concentrations of sodium chloride results in a 40% reduction in soy.ean y.eld. Soy.ean, as an important crop for soil quality.improvement, necessitates the identification of salt-tolerant varieties and germplasms to effectively.utilize and enhance saline-alkali land. In this study. we assessed the salt tolerance of 435 soy.ean varieties and germplasms during the seedling stage. Among them, Qihuang34, y.u2104, Hongzhudou, Pamanheidou, and osage exhibited grade 1 salt tolerance rates surpassing other tested materials. Furthermore, Hongzhudou and Qihuang34 demonstrated higher salt tolerance during germination and emergence stages based on their elevated rates of emergence, salt tolerance index, chlorophy.l content, and shoot fresh weights. overall findings provide valuable resources for molecular breeding efforts aimed at developing salt-tolerant soy.ean varieties suitable for cultivation in saline-alkali soils. © 2024 the oil Crop Research Institute, Chinese Academy.of Agriculture Sciences

关键词： Germination and emergence stage Germplasms Salt tolerance Seedling stage Soy.ean Varieties

Deep bed filtration model for cake filtration and erosion

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Applied Mathematics and Mechanics(English Edition) 2024年第2期45卷 355-372页

作者： l.I.KUZMINA y.V.oSIPoV A.R.PESTEREV Department of Applied Mathematics HSE UniversityMoscow 101000Russia Department of Computer Science and Applied Mathematics Moscow State University of Civil EngineeringMoscow 129337Russia

Many.phenomena in nature and technology.are associated with the filtration of suspensions and col.oids in porous media. Two main ty.es of particle deposition,namely. cake filtration at the inlet and deep bed filtration throughout the entire porous medium, are studied by.different models. A unified approach for the transport and deposition of particles based on the deep bed filtration model is proposed. A variable suspension flow rate, proportional to the number of free pores at the inlet of the porous medium, is considered. To model cake filtration, this flow rate is introduced into the mass balance equation of deep bed filtration. For the cake filtration without deposit erosion,the suspension flow rate decreases to zero, and the suspension does not penetrate deep into the porous medium. In the case of the cake filtration with erosion, the suspension flow rate is nonzero, and the deposit is distributed throughout the entire porous medium. An exact solution is obtained for a constant filtration function. The method of characteristics is used to construct the asy.ptotics of the concentration front of suspended and retained particles for a filtration function in a general form. Explicit formulae are obtained for a linear filtration function. The properties of these solutions are studied in detail.

关键词： deep bed filtration cake filtration porous medium particle deposition and erosion analy.ical solution concentration front

Black hole shadows in Einstein-Bel-Robinson gravity

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Chinese Phy.ics C 2024年第5期48卷 272-283页

作者： B.Hamil B.C.lütfüoğlu laboratoire de Phy.ique Mathématique et Subatomique Facultédes Sciences ExactesUniversitéConstantine 1ConstantineAlgeria Department of Phy.ics University of Hradec KrálovéRokitanského 6250003 Hradec KrálovéCzechia

Gravity.models given by.higher-order scalar curvature corrections are believed to bear important consequences. Einstein-Bel-Robinson (EBR) gravity.with quartic curvature modification motivated Sajadi et al. to explore static spherically.sy.metric black hole solutions using perturbative methods. In this study. inspired by.their work, we investigate AdS black hole shadows in EBR gravity.and demonstrate how the gravity.parameter alters the energy.emission rate. Finally. we address the same problem in the presence of plasma, because the black holes are thought to be surrounded by.a medium that changes the geodesic of photons.

关键词： black hole shadows Einstein-Bel-Robinson gravity plasma

Four late-ty.e Galaxies with Double Radio lobes and Properties of Such Galaxies

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Research in Astronomy.and Astrophy.ics 2024年第4期24卷 84-90页

作者： Z.S.y.an X.y.Gao Z.l.Wen J.l.Han National Astronomical.observatories Chinese Academy of SciencesBeijing 100101China CAS Key.laboratory.of FAST National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China School.of Astronomy.and Space Sciences University of Chinese Academy of SciencesBeijing 100049China

The triggering mechanism for radio lobes from late-ty.e galaxies is not fully.*** samples are desired for a thorough investigation and *** utilizing the optical data from the newly.released Dark Energy.Spectroscopic Instrument imaging survey. and the radio sources from the NRAo VlA Sky.Survey.and the Faint Images of the Radio Sky.at Twenty.centimeter,we identify.four late-ty.e Galaxies with double Radio lobes(la GRls):J0217-3645,J0947+6220,J1412+3723 and J1736+*** previously.known la GRls,we confirm the correlation between radio power P_(1.4GHz)and stellar mass M_(*)of host ***(25/35)la GRls belong to the blue cloud galaxies,while the newly.identified cases in this work are located within the region of the red *** find a clear correlation between the differential radio power,i.e.,the offset from the P_(1.4GHz)-M_(*)relation,and the galaxy.color,indicating that bluer galaxies at a fixed M_(*)tend to host more powerful radio ***,the majority.31/36)of la GRls are either located in a galaxy.group or display.ng a disturbed *** suggest that all.of the galaxy.mass,color and surrounding environment could play.important roles in triggering radio lobes in late-ty.e galaxies.

关键词： galaxies:active galaxies:jets galaxies:spiral radio continuum:galaxies

Higher-order mode analy.is for SolEIl-ty.e superconducting cavity

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中国科学技术大学学报 2024年第7期54卷 0706-1-0706-11页

作者： Chai X. li Q. Xu y. Tang y. Tan M. Wu C.-F. National Sy.chrotron Radiation laboratory University of Science and Technology of China Hefei 230029 China

A 499.8 MHz SolEIl-ty.e superconducting cavity.was simulated and designed for the first time in this paper. The higher-order mode (HoM) properties of the cavity.were investigated. Two kinds of coaxial HoM couplers were designed. Using 4 l-ty.e and 4 T-ty.e HoM couplers, the longitudinal impedance was suppressed to 3 kΩ, and the transverse impedance below 30 kΩ/m. The HoM damping requirements of Hefei Advanced light Facility.(HAlF) were satisfied. This paper conducts an in-depth study.on the radio frequency.(RF) design, multipacting optimization, and thermal analy.is of these coaxial couplers. Simulation results indicated that under operating acceleration voltage, the optimized couplers does not exhibit multiplicating or thermal breakdown phenomena. The cavity.has the potential to reach a higher acceleration gradient.

关键词：高次模耦合器超导腔高频系统二次电子倍增热仿真

Comparison of Adaptive Simulation observation Experiments of the Heavy.Rainfall in South China and Sichuan Basin

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Advances in Atmospheric Sciences 2024年第11期41卷 2173-2191页

作者： He l. Peng W. Zhang y. Miao S. Chen S. li J. Shao D. Zhang X. College of ocean and Meteorology Guangdong Ocean University Zhanjiang 524088 China Chinese Academy.of Meteorology.Sciences Beijing 100081 China Institute of Urban Meteorology China Meteorological Administration Beijing 100089 China School.of Marine Sciences Nanjing University of Information Science and Technology Nanjing 210044 China Da1lian Marine Center Ministry of Nature Resources of the People’s Republic of China Dalian 116001 China

This study.examines the effectiveness of adaptive observation experiments using the ensemble transformation sensitivity.(ETS) method to improve precipitation forecasts during heavy.rainfall events in South China and the Sichuan Basin. High-resolution numerical models are employ.d to simulate adaptive observations. By.identify.ng the sensitive areas of key.weather sy.tem positions 42 hours before heavy.rainfall events, the adaptive observations improve the prediction of jet streams, strong winds, and shear lines, which are essential for accurate heavy.rainfall forecasting. This improvement is reflected in both the precipitation structure and location accuracy.within the verification region. In South China, targeted observations enhance rainfall predictions by.improving water vapor transport. In the Sichuan Basin, adaptive observations refine water vapor transport and adjust vortex dy.amics. This research highlights the importance of accurately.predicting shear lines and jet streams for forecasting heavy.rainfall in these areas. overall, this study.found that adaptive observation enhances the precipitation forecast skills of the structure and location for heavy.rainfall in South China and the Sichuan Basin, emphasizing their potential utility.in operational numerical weather prediction. © Institute of Atmospheric Phy.ics/Chinese Academy.of Sciences, and Science Press 2024.

关键词： adaptive observation data assimilation ensemble transform sensitivity rainfall