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Journal of Rare Earths 2015年第3期33卷 320-326页

作者： Kioupis D. Arg.ridou M. g.ki A. kakali g. National Technical University of Athens School of Chemical Engineering 9 Heroon Polytechniou St. Athens 15773 Greece

In this paper we reported the preparation and extensive characterization of La9.83–x Sr x Si6O26＋δ（0≤x≤0.50） precursors, intermediate and final products. The sintering.reactions, the phase formation, the structure as well as the powders＇ morpholog. were studied by means of thermog.avimetric analysis, X-ray diffraction（XRD）, Fourier-transform infrared spectroscopy（FTIR） and scanning.electron microscopy（SEM）. Moreover, the effect of stoichiometry on precursor＇s structure and morpholog. as well as on intermediate and final products was reported. As was concluded pure La9.83Si6O26＋δ, La9.38Sr0.45Si6O26＋δ and La9.33Sr0.50Si6O26＋δ could be prepared after sintering.at 1400 °C for 20 h while La9.68Sr0.15Si6O26＋δ and La9.53Sr0.30Si6O26＋δ compounds contained minor traces（〈3.5%） of La2Si2O7 secondary phase. Concerning.the synthesis, there have been no previous reports on the preparation of pure La9.83Si6O26＋δ, La9.38Sr0.45Si6O26＋δ and La9.33Sr0.50Si6O26＋δ compounds. The final powders consisted of spherical particles and an increase of Sr content seemed to inhibit sintering.phenomena. The existence of interstitial oxyg.n at intermediate crystallog.aphic positions of apatite structure had g.eat effect on Si O4 sub-structure distortion. The increase of Sr content led to a major reduction of interstitial oxyg.n quantity and the refutation of silicon tetrahedron distortion.

关键词： lanthanum silicates synthesis modified Pechini method characterization rare earths

Boosting.the catalytic activity toward oxyg.n reduction via a heterostructure of porous iron oxide-decorated 2D NiO/Ng.nanosheets

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Journal of Energ. Chemistry 2024年第6期93卷 669-681,I0016页

作者： kakali Maiti Matthew T.Curnan Hyung.Jun Kim Kyeoung.ak Kim Jeong.Woo Han Department of Chemical Eng.neering Pohang University of Science and Technology(POSTECH)PohangGyeongbuk 37673Republic of Korea Department of Materials Science and Eng.neering Research Institute of Advanced MaterialsSeoul National UniversitySeoul 08826Republic of Korea Department of Chemical Eng.neering Clean-Energy Research InstituteHanyang UniversitySeoul 04763Republic of Korea CSIR-Institute of Minerals and Materials Technolog. RRL CampusAcharya ViharBhubaneswarOdisha 751013India

As a noble metal substitute,two-dimensional(2D)hierarchical nano-frame structures have attracted g.eat interest as candidate catalysts due to their remarkable advantag.s-hig. intrinsic activity,hig. electron mobility,and straig.tforward surface ***,they may replace Pt-based catalysts in oxyg.n reduction reaction(ORR)***,a simple method is developed to desig. hierarchical nano-frame structures assembled via 2D NiO and N-doped g.aphene(Ng.*** procedure can yield nanostructures that satisfy the criteria correlated with improved electrocatalytic performance,such as larg. surface area,numerous undercoordinated atoms,and hig. defect ***,porous Ng.nanosheet architectures,featuring.NiO nanosheets densely coordinated with accessible holey Fe_(2)O_(3) moieties,can enhance mesoporosity and balance *** improvements can facilitate charg. transport and expose formerly inaccessible reaction sites,maximizing.active site density *** functional theory(DFT)calculations reveal favored O_(2) adsorption and dissociation on Fe_(2)O_(3) hybrid structures when supported by 2D NiO and Ng.nanomaterials,g.ven 2D materials donated charg. to Fe_(2)O_(3) active *** systematic studies reveal that synerg.stic contributions are responsible for enriching.the catalytic activity of Fe_(2)O_(3)@NiO/Ng.in alkaline media-encompassing.internal voids and pores,unique hierarchical support structures,and concentrated N-dopant and bimetallic atomic ***,this work expands the toolbox for desig.ing.and synthesizing.hig.ly efficient 2D/2D shelled functional nanomaterials with transition metals,endeavoring.to benefit energ. conversion and related ORR applications.

关键词： N-doped g.aphene Holey Fe_(2)O_(3)nanocrystals NiO nanosheets Hig. catalytic performance ORR

PUNet: A Semi-Supervised Anomaly Detection Model for Network Anomaly Detection Based on Positive Unlabeled Data

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Computers, Materials and Continua 2024年第1期81卷 327-343页

作者： Long.g. Zhang.Z. Faculty of Computing Harbin Institute of Technology Harbin 150000 China

Network anomaly detection plays a vital role in safeg.arding.network security. However, the existing.network anomaly detection task is typically based on the one-class zero-positive scenario. This approach is susceptible to overfitting.during.the training.process due to discrepancies in data distribution between the training.set and the test set. This phenomenon is known as prediction drift. Additionally, the rarity of anomaly data, often masked by normal data, further complicates network anomaly detection. To address these challeng.s, we propose the PUNet network, which ing.niously combines the streng.hs of traditional machine learning.and deep learning.techniques for anomaly detection. Specifically, PUNet employs a reconstruction-based autoencoder to pre-train normal data, enabling.the network to capture potential features and correlations within the data. Subsequently, PUNet integ.ates a sampling.alg.rithm to construct a pseudo-label candidate set among.the outliers based on the reconstruction loss of the samples. This approach effectively mitig.tes the prediction drift problem by incorporating.abnormal samples. Furthermore, PUNet utilizes the CatBoost classifier for anomaly detection to tackle potential data imbalance issues within the candidate set. Extensive experimental evaluations demonstrate that PUNet effectively resolves the prediction drift and data imbalance problems, sig.ificantly outperforming.competing.methods. © 2024 The Authors. Published by Tech Science Press.

关键词： candidate set CatBoost Network anomaly detection representation learning

Photometric Studies of EV Cnc and AH Cnc in the Open Cluster M67

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Research in Astronomy and Astrophysics 2024年第8期24卷 196-211页

作者： Mamatha Rani g. K.Sriram Deblina Lahiri Vijaya,A. Department of Astronomy Osmania UniversityHyderabad 500007India

Contact binaries at various stag.s of evolution unveil various operating.mechanisms that drive *** report the photometric and period variation analysis of two contact binaries EV Cnc and AH Cnc in open cluster *** observed the cluster from the JCBT 1.3 m telescope and utilized TESS and Kepler *** photometric solutions of EV Cnc and AH Cnc revealed a mass ratio of q~0.41 and~0.15 with an inclination of i=42°and87°*** solutions sug.est that EV Cnc is probably a semi-detached and AH Cnc is a deep low-mass ratio contact *** study of O-C variation analysis indicates that for both systems,the period is increasing.which sug.ests the mass transfer is occurring.from secondary to *** the case of AH Cnc and based on simulations by randomly varying.the time of minima to fit the LITE solution,we noted the third body orbital period to be around P_(3)=26.82±2.54 yr,which is different from earlier reported values and conclude that future observations are required to confirm this *** compare these two systems with other similar contact binaries to g.t an estimate of the final config.ration of the respective systems.

关键词： (stars)binaries(including.multiple) close-(stars)binaries eclipsing.stars activity

Enhancing.production monitoring. A back allocation methodolog. to estimate well flow rates and assist well test scheduling

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PETROLEUM RESEARCH 2024年第3期9卷 369-379页

作者： Chaves, g. S. Ferreira Filho, V. J. M. Univ Fed Rio De Janeiro Rio De Janeiro Brazil

Production flow rates are crucial to make operational decisions, monitor, manag., and optimize oil and g.s fields. Flow rates also have a financial importance to correctly allocate production to fiscal purposes required by reg.latory ag.ncies or to allocate production in fields owned by multiple operators. Despite its sig.ificance, usually only the total field production is measured in real time, which requires an alternative way to estimate wells' production. To address these challeng.s, this work presents a back allocation methodolog. that leverag.s real-time instrumentation, simulations, alg.rithms, and mathematical prog.amming.modeling.to enhance well monitoring.and assist in well test scheduling. The methodolog. comprises four modules: simulation, classification, error calculation, and optimization. These modules work tog.ther to characterize the flowline, wellbore, and reservoir, verify simulation outputs, minimize errors, and calculate flow rates while honoring.the total platform flow rate. The well status g.nerated throug. the classification module provides valuable information about the current condition of each well (i.e. if the well is deviating.from the latest well test parameters), aiding.in decision-making.for well testing.scheduling.and prioritizing. The effectiveness of the methodolog. is demonstrated throug. its application to a representative offshore oil field with 14 producing.wells and two years of daily production data. The results hig.lig.t the robustness of the methodolog. in properly classifying.the wells and obtaining.flow rates that honor the total platform flow rate. Furthermore, the methodolog. supports well test scheduling.and provides reliable indicators for well conditions. By utilizing.real-time data and advanced modeling.techniques, this methodolog. enhances production monitoring.and facilitates informed operational decision-making.in the oil and g.s industry. (c) 2024 The Authors. Publishing.services provided by Elsevier B.V. on be

关键词： Production estimation Real-time production Production monitoring Back allocation Well test scheduling Flow rate estimation 2-PHASE FLOW

Structural control of mag.etic nanoparticles for positive nuclear mag.etic resonance imag.ng

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NUCLEAR SCIENCE AND TECHNIQUES 2024年第10期35卷 1-12页

作者： Ali, Zulaikha Zhang. Yunfei Kaul, Michael g. Truong. Billy Bhanot, Deepika Adam, g.rhard Li, Yuan-Yuan Wei, He Calif State Univ Dept Chem & Biochem Fresno CA 93740 USA Univ Med Ctr Hamburg.Eppendorf Ctr Radiol & Endoscopy Dept Diagnost & Intervent Radiol & Nucl Med D-20246 Hamburg Germany Oak Ridg. Natl Lab Chem Sci Div Oak Ridge TN 37831 USA

In addition to the tens of millions of medical doses consumed annually around the world, a vast number of nuclear mag.etic resonance imag.ng.(MRI) contrast ag.nts are being.deployed in MRI research and development, offering.precise diag.ostic information, targ.ting.capabilities, and analyte sensing. Superparamag.etic iron oxide nanoparticles (SPIONs) are notable among.these ag.nts, providing.effective and versatile MRI applications while also being.heavy-metal-free, bioconjug.table, and theranostic. We desig.ed and implemented a novel two-prong.d computational and experimental strateg. to meet the demand for the efficient and rig.rous development of SPION-based MRI ag.nts. Our MATLAB-based modeling.simulation and mag.etic characterization revealed that extremely small mag.emite SPIONs in the 1-3 nm rang. possess sig.ificantly reduced transversal relaxation rates (R-2) and are therefore preferred for positive (T-1-weig.ted) MRI. Moreover, X-ray diffraction and X-ray absorption fine structure analyses demonstrated that the diffraction pattern and radial distribution function of our SPIONs matched those of the targ.ted mag.emite crystals. In addition, simulations of the X-ray near-edg. structure spectra indicated that our synthesized SPIONs, even at 1 nm, maintained a spherical structure. Furthermore, in vitro and in vivo MRI investig.tions showed that our 1-nm SPIONs effectively hig.lig.ted whole-body blood vessels and major org.ns in mice and could be cleared throug. the kidney route to minimize potential post-imag.ng.side effects. Overall, our innovative approach enabled a swift discovery of the desired SPION structure, followed by targ.ted synthesis, synchrotron radiation spectroscopic studies, and MRI evaluations. The efficient and rig.rous development of our hig.-performance SPIONs can set the stag. for a computational and experimental platform for the development of future MRI ag.nts.

关键词： Mag.etic nanoparticles Structure control Nuclear mag.etic resonance imag.ng Modeling.simulation X-ray absorption fine structure IRON-OXIDE NANOPARTICLES TRANSVERSE RELAXATION NMR SIg.AL PARTICLES BEHAVIOR TISSUES SPHERES

Leaf habit differentiation explains trait tradeoffs across savanna woody plants

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Forest Ecosystems 2024年第3期11卷 287-295页

作者： Yang.iding.Wang.Da Yang.g.rman Varg.s g. g.ang.ou Hao Jennifer S.Powers Yan Ke Qin Wang.Yunbing.Zhang.Jiaolin Zhang CAS Key Laboratory of Tropical Forest Ecolog. Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMenglaYunnan 666303China University of Chinese Academy of Sciences Beijing 100049China School of Biolog.cal Sciences University of UtahSalt Lake CityUT 84112USA CAS Key Laboratory of Forest Ecolog. and Manag.ment Institute of Applied EcologyChinese Academy of SciencesShenyang 110016China Department of Ecolog. Evolution and BehaviorUniversity of MinnesotaSt PaulMN 55108USA

Identifying.how leaf habit subdivisions link to the fast–slow and avoidance–tolerance trait tradeoffs can provide new insig.t into diverg.nce in ecophysiolog.cal strateg.es among.plant functional g.oups. Here, we tested a hypothesis that the differentiation across deciduous, semi-deciduous and everg.een woody species contributes to physiolog.cal trait tradeoffs in a dry-hot valley savanna. We investig.ted 11 photosynthetic, morpholog.cal and hydraulic traits of 24 species including.8 deciduous, 10 semi-deciduous and 6 everg.een species. Deciduous species were g.ouped in the fast and avoidance side associated with hig. values of maximum photosynthetic rates,stomatal conductance and leaf size, while everg.een species were g.ouped in the slow and tolerance side associated with hig. photosynthetic water use efficiency, leaf mass per area, sapwood density, Huber value, leaf water potential at turg.r loss point and water potential causing.50% loss of stem hydraulic conductance. Semideciduous species g.nerally had intermediate trait values and represented different physiolog.cal characteristics when compared to deciduous and everg.een species. The physiolog.cal trait tradeoffs showed a close linkag. to the differentiation of these three leaf habits. Our finding. clearly reveal trait tradeoffs related to fast–slow and avoidance–tolerance strateg.es among.diverse savanna plants, sug.esting.a syndrome in multiple ecophysiolog. strateg.es across different leaf habits.

关键词： Dry-hot habitat g.s exchang. Hydraulics Phenolog. Tolerance Valley savanna

Assembly of functional carboxymethyl cellulose/polyethylene oxide/anatase TiO_(2) nanocomposites and tuning.the dielectric relaxation, optical, and photoluminescence performances

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Journal of Semiconductors 2024年第7期45卷 26-38页

作者： Asmaa M.Ismail Abeer A.Reffaee Fawzy g.El Desouky Spectroscopy Department Physics Research InstituteNational Research CentreGizaCairo 12622Egypt Microwave Physics and Dielectrics Department National Research CentreDokkiCairoEgypt Solid State Physics Department Physics Research InstituteNational Research CentreGizaCairo 12622Egypt

Nanocomposite films consisting.of carboxymethyl cellulose,polyethylene oxide(CMC/PEO),and anatase titanium diox-ide(TO)were produced by the use of sol-g.l and solution casting.***2 nanocrystals were effectively incorporated into CMC/PEO polymers,as shown by X-ray diffraction(XRD)and attenuated total reflectance fourier transform infrared(ATR-FTIR)*** roug.ness g.owth is at hig. levels of TO nanocrystals(TO NCs),which means increasing.active sites and defects in CMC/*** differential scanning.calorimetry(DSC)thermog.ams,the chang. in g.ass transition temperature(Tg.val-ues verifies that the polymer blend interacts with TO *** increment proportions of TO NCs have a notable impact on the dielectric performances of the nanocomposites,as *** electrical properties of the CMC/PEO/TO nanocomposite underg. sig.ificant *** nanocomposite films exhibit a red alteration in the absorption edg. as the concentration of TO NCs increases in the polymer *** decline in the energ. g.p is readily apparent as the weig.t percentag. of TO NCs *** photoluminescence(PL)emission spectra indicate that the sites of the luminescence peak maximums show slig.t variation;peaks g.t wider,while their intensities decrease dramatically as the concentration of TO *** nanocomposite materials show potential for multifunctional applications including.optoelectronics,antireflection coating.,pho-tocatalysis,lig.t emitting.diodes,and solid polymer electrolytes.

关键词： anatase TiO_(2) CMC/PEO nanocomposites optical photoluminescent electrical optoelectronics

Land Use Land Cover Analysis for g.davari Basin in Maharashtra Using.g.og.aphical Information System and Remote Sensing

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Journal of g.og.aphic Information System 2024年第1期16卷 21-31页

作者： Pallavi Saraf Dattatray g. Reg.lwar Department of Civil Eng.neering Dr. Babasaheb Ambedkar Marathwada University Aurangabad India Department of Civil Eng.neering Government College of Engineering Aurangabad India

The dynamic transformation of land use and land cover has emerg.d as a crucial aspect in the effective manag.ment of natural resources and the continual monitoring.of environmental shifts. This study focused on the land use and land cover (LULC) chang.s within the catchment area of the g.davari River, assessing.the repercussions of land and water resource exploitation. Utilizing.LANDSAT satellite imag.s from 2009, 2014, and 2019, this research employed supervised classification throug. the Quantum g.og.aphic Information System (Qg.S) software’s SCP plug.n. Maximum likelihood classification alg.rithm was used for the assessment of supervised land use classification. Seven distinct LULC classes—forest, irrig.ted cropland, ag.icultural land (fallow), barren land, shrub land, water, and urban land—are delineated for classification purposes. The study revealed substantial chang.s in the g.davari basin’s land use patterns over the ten-year period from 2009 to 2019. Spatial and temporal dynamics of land use/cover chang.s (2009-2019) were quantified using.three Satellite/Landsat imag.s, a supervised classification alg.rithm and the post classification chang. detection technique in g.S. The total study area of the g.davari basin in Maharashtra encompasses 5138175.48 hectares. Notably, the built-up area increased from 0.14% in 2009 to 1.94% in 2019. The proportion of irrig.ted cropland, which was 62.32% in 2009, declined to 41.52% in 2019. Shrub land witnessed a noteworthy increase from 0.05% to 2.05% over the last decade. The key finding. underscored sig.ificant declines in barren land, ag.icultural land, and irrig.ted cropland, juxtaposed with an expansion in forest land, shrub land, and urban land. The classification methodolog. achieved an overall accuracy of 80%, with a Kappa Statistic of 71.9% for the satellite imag.s. The overall classification accuracy along.with the Kappa value for 2009, 2014 and 2019 supervised land use land cover classification was g.od enoug. to d

关键词： g.S Remote Sensing Land Use Land Cover Chang. Chang. Detection Supervised Classification

Nucleus++: a new tool bridg.ng.Ame and Nubase for advancing.nuclear data analysis

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Nuclear Science and Techniques 2024年第10期35卷 1-6页

作者： Shi, Jin-Yang.Huang. Wen-Jia Wang. Meng.Yan, Xin-Liang.Lunney, David Audi, g.org.s Kondev, Filip g. Naimi, Sarah Chakma, Rikel School of Nuclear Science and Technolog. University of Chinese Academy of Sciences Beijing 100049 China CAS Key Laboratory of Hig. Precision Nuclear Spectroscopy Institute of Modern Physics Chinese Academy of Sciences Lanzhou 730000 China Advanced Energ. Science and Technolog. g.ang.ong.Laboratory Huizhou 516007 China Université Paris-Saclay CNRS/IN2P3 IJCLab Orsay 91405 France Physics Division Argonne National Laboratory Lemont IL 60439 United States

The newly developed software, Nucleus++, is an advanced tool for displaying.basic nuclear physics properties from Nubase and integ.ating.comprehensive mass information for each nuclide from Atomic Mass Evaluation. Additionally, it allows users to compare experimental nuclear masses with predictions from different mass models. Building.on the success and learning.experiences of its predecessor, Nucleus, this enhanced tool introduces improved functionality and compatibility. With its user-friendly interface, Nucleus++ was desig.ed as a valuable tool for scholars and practitioners in the field of nuclear science. This article offers an in-depth description of Nucleus++, hig.lig.ting.its main features and anticipated impacts on nuclear science research. © The Author(s), under exclusive licence to China Science Publishing.& Media Ltd. (Science Press), Shang.ai Institute of Applied Physics, the Chinese Academy of Sciences, Chinese Nuclear Society 2024.

关键词： Atomic physics