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行星科学研究中热发射光谱的实验测量与定标方法

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空间科学学报 2024年第2期44卷 270-286页

作者：杨亚洲 MILLIKeN Ralph e BRAMBLe Michael s PATTeRsON William R 邹永廖刘洋中国科学院国家空间科学中心空间天气学国家重点实验室北京100190 布朗大学地球环境与行星科学学院普罗维登斯02912

准确的物质组成信息是解译行星体形成与演化历史的关键,可见–近红外遥感光谱探测一直是获取行星表面成分的主要技术手段.在热红外谱段光谱特征更为丰富,因此随着探测技术的发展,其在行星探测中得到越来越多的应用.尤其是在目前已经实... 详细信息

准确的物质组成信息是解译行星体形成与演化历史的关键,可见–近红外遥感光谱探测一直是获取行星表面成分的主要技术手段.在热红外谱段光谱特征更为丰富,因此随着探测技术的发展,其在行星探测中得到越来越多的应用.尤其是在目前已经实施与立项的国内外小行星探测任务中,都将热发射光谱仪作为核心载荷之一.为了更好地对将来获取的热发射光谱数据进行解译,建立科学合理的数据处理与定标方案是必不可少的.本文对用于行星科学研究的热发射光谱测量装置的设计、测量及数据处理方法进行了系统分析.针对低温、真空条件下热发射测量过程中样品辐射信号与仪器辐射信号难以分离的问题,提出并论证了基于傅里叶变换红外光谱仪原始测量信号–干涉图的数据处理方法.该方法可以更为有效地分离出样品实际辐射信号,从而获得更为准确的发射率光谱数据.研究结果可为国内相关热发射测量装置的设计与搭建以及未来天问二号等探测数据的处理与科学解译提供参考.

关键词：行星探测热发射光谱实验室测量定标

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On B(5,20)2-Groups

Algebra Colloquium 2024年第3期31卷 429-440页

作者： e.A.Alhassan Y.L.Tan Y.Li school of Mathematical sciences Jiangsu UniversityZhenjiangJiangsu 212013China Department of Mathematics Brock UniversitySt.CatharinesOntario L2S 3A1Canada

A finite group G is said to be a B(n,k)group if for any n-element subset[a_(1),…,a_(n)]of G,|{a_(i)a_(j)|1≤i,j≤n}|≤*** is of interest to characterize the structure of B(n,k)groups for n(n+1)/2≤k≤n^(2)-*** B(5,k)groups for 15≤k≤19 have been investigated by several *** this paper,we give a complete characterization of B(5,20)2-groups by showing there are five classes of such groups which are nontrivial and nonabelian.

关键词： B(n,k)groups small squaring property central extension GAP

study of the Physical and Mechanical Properties of Titanium in Volume by the MeAM Method

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Modeling and Numerical simulation of Material science 2024年第1期14卷 58-68页

作者： Yahnn J. Mighensle Mimboui Alain s. Dzabana Honguelet Timothée Nsongo Faculty of science and Technology Marien Ngouabi University Brazzaville Congo Research Group on Physical and Chemical Properties of Materials Brazzaville Congo Association Alpha sciences Beta Technologies Brazzaville Congo Geological and Mining Research Centre Brazzaville Congo

In this work we present the results of our study on the physical and mechanical properties of titanium in volume. The work consisted in determining its physical and mechanical properties under different crystallographic structures (HCP, FCC, BCC and sC) using the Modified embedded Atom Method (MeAM) and the MeAM potential of titanium. We used the LAMMPs calculation code, based on classical molecular dynamics, to determine the most stable structure of titanium, which is the hexagonal compact structure (HCP) with crystal parameters a = 2.952 Å and c = 4.821 Å and a cohesion energy of -4.87 eV. This structure is seconded by the cubic centred structure (BCC) with a lattice parameter a = 3.274 Å and a cohesive energy of -4.84 eV. It was shown that titanium can crystallise into a third structure which is the face-centred cubic (FCC) structure with a lattice parameter a = 4.143 Å and a cohesive energy of -4.82 eV. The results obtained in this study were compared with the theoretical results and showed considerable agreement.

关键词： MeAM Potential LAMMPs Code Molecular Dynamics elastic Constants Modules Ovito

Highly Defective Dark TiO_(2) Modified with Pt: effects of Precursor Nature and Preparation Method on Photocatalytic Properties

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Transactions of Tianjin University 2024年第2期30卷 198-209页

作者： e.D.Fakhrutdinova O.A.Reutova T.A.Bugrova I.Yu.Ovsyuk L.s.Kibis O.A.stonkus D.B.Vasilchenko O.V.Vodyankina V.A.svetlychnyi National Research Tomsk state University TomskRussia 634050 Novosibirsk state University NovosibirskRussia 630090 Boreskov Institute of Catalysis NovosibirskRussia 630090 Nikolaev Institute of Inorganic Chemistry NovosibirskRussia 630090

The study focused on the modification with platinum of dark defective titania obtained via pulsed laser ablation. Both the method of Pt introduction and the nature of the Pt precursor were varied. All samples exhibited similar phase compositions, specific surface areas, and Pt contents. High-resolution transmission electron microscopy coupled with pulsed CO adsorption revealed increased dispersity when photoreduction and the hydroxonitrate complex (Me _(4) N) _(2) [Pt _(2) (OH) _(2) (NO _(3) ) _(8) ] were used. The sample featured a high content of single-atom species and subnano-sized Pt clusters. The X-ray photoelectron spectroscopy results showed that the photoreduction method facilitated the appearance of a larger number of Pt ^(2+) states, which appeared owing to the strong metal-support interaction (sMsI) eff ect of the transfer of electron density from the electron-saturated defects on the TiO _(2) surface to Pt ^(4+) . In the hydrogen evolution reaction, samples with a significant fraction of the Pt ^(2+) ionic component, capable of generating short-lived Pt^(0) single-atom sites under irradiation due to the sMsI eff ect, exhibited the highest photocatalytic activity. The 0.5Pt(C)/TiO_(2) -Ph sample exhibited the highest hydrogen yield with a quantum efficiency of 0.53, retaining its activity even after 8 h of operation.

关键词： Dark(black)TiO_(2) Pulsed laser ablation Platinum reduction method Precursor type Photocatalysis Hydrogen evolution reaction

New record of the feather star Palaeocomatella hiwia(echinodermata:Crinoidea:Comatulida)from Zhenbei seamount in south China sea:new insights into the taxonomic position of Palaeocomatella

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Journal of Oceanology and Limnology 2024年第1期42卷 244-251页

作者： shao’e sUN Zijie MeI Zhongli sHA Jing WANG Nansheng CHeN Department of Marine Organism Taxonomy and Phylogeny Institute of OceanologyChinese Academy of SciencesQingdao 266071China CAs Key Laboratory of Marine ecology and environmental sciences Institute of OceanologyChinese Academy of SciencesQingdao 266071China Laoshan Laboratory Qingdao 266237China shandong Province Key Laboratory of experimental Marine Biology Institute of OceanologyChinese Academy of SciencesQingdao 266071China Center for Ocean Mega-science Chinese Academy of SciencesQingdao 266071China University of Chinese Academy of sciences Beijing 100049China

One specimen belonging to the family Comatellinae was collected from the Zhenbei seamount(332.5–478.2 m)in the south China sea in July *** on the morphological characters,the specimen was identified as Palaeocomatella hiwia McKnight,*** is first recorded from China sea and redescribed in *** specimen differs from the original description from New Zealand for never showing syzygy at br4+5 or br5+6 on interior and br1+2 on exterior ***,it is much conform to the redescription to specimens from Indonesia,with only differences in position of the second syzygy and distalmost pinnule *** is deposited in the Institute of Oceanology,Chinese Academy of *** analyses based on the mitochondrial c oxidase subunit I(COI)and 16s rRNA genes indicated that *** was nested within the tribe Phanogeniini and clustered with Aphanocomaster ***,*** showed same morphological features in terms of mouth placement,comb location,and number of comb teeth rows as other genera of ***,we suggest that the genus Palaeocomatella should be put in the tribe Phanogeniini.

关键词： new record Palaeocomatella hiwia McKnight 1977 south China sea phylogenetic relationship taxonomy

Potential of Bamboo species Guadua trinii and Guadua angustifolia for Nanocellulose Production

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Journal of Renewable Materials 2024年第9期12卷 1541-1555页

作者： Agatha e.R.Prado Gárate Fernando e.Felissia María Cristina Area Teresa suirezs María evangelina Vallejos Círculo de Investigación del Bambú Universidad Nacional Agraria La Molina(UNALM)Lima15026Perú Instituto de Materiales de Misiones(IMAM) Universidad Nacional de Misiones(UNaM)Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET)Facultad de Ciencias ExactasQuímicas y Naturales(FCEQYN)Programa de Celulosa y Papel(PROCyP)Posadas3300Argentina Instituto de Materiales de Misiones(IMAM) Universidad Nacional de Misiones(UNaM)Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET)Facultad de Ciencias Forestales(FCF)Eldorado3380Argentina

Non-traditional lignocellulosic materials are a significant resource for producing high-value products,including *** work studied the nanocellulose obtention from chemical pulps of the two fast-growing bamboo species,Guadua trinii,and Guadua *** pulps were produced by soda-anthraquinone(s)pulping from both autohydrolysis-pretreated(H)and unpretreated bamboo ***-pretreated(sHP)and unpretreated soda-anthraquinone(AQ)(sP)pulps were characterized by yield,Kappa number,alpha,beta,and gamma cellulose,degree of polymerization,water retention value,and *** nanocellulose was produced by a sequential chemical oxidation treatment(2,2,6,6-tetramethylpiperidine-1-oxyl,TeMPO reagent)and mechanical *** was characterized by carboxylic group content and *** results revealed that autohydrolysis pretreatment resulted in a higher hemicelluloses extraction in *** contrast,the pulping yield of unpretreated samples was higher for ***,and the soda-AQ pulps from this species exhibited better delignification than the autohydrolysis-pretreated *** crystallinity index values of the obtained pulps were high(>80%),and the alpha-cellulose contents were *** viscosities of the aqueous nanocellulose suspensions were higher for the nanocellulose solutions obtained from the unpretreated soda-AQ ***,nanocellulose from *** unpretreated soda-AQ pulps had a higher rate of carboxylic *** results of this work are significant in assessing the potential of both bamboo species as a source of high-value products within the biorefinery framework because the viscosities of the aqueous nanocellulose suspensions depend on the size and shape of *** has significant importance for industrial unit operations and potential applications.

关键词： Natural fiber Guadua angustifolia Guadua trinii soda-anthraquinone pulp nanocellulose

Highly selective and eco-friendly dihydroisoquinoline synthesis via Cu/Co synergistic catalysis in Cu NPs@MOFs catalyst under mild conditions

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science China Chemistry 2024年第5期67卷 1561-1568页

作者： Peng-Fei Guo Ze-Long Liang Yue-e Jiao Hang Xu Bin Zhao Key Laboratory of Advanced energy Material Chemistry Renewable Energy Conversion and Storage CenterDepartment of ChemistryNankai UniversityTianjin 300071China

3,4-Dihydroisoquinoline(DHIQ)is an important precursor used in the production of drugs for treating cancer,HIV,Alzheimer's disease,*** studies on DHIQ synthesis show low catalytic selectivity due to the susceptible over-oxidation feedstock of1,2,3,4-tetrahydroisoquinoline(THIQ),which often requires alkali ***,it is desirable yet challenging to explore a highly selective and efficient oxydehydrogenation capacity for DHIQ synthesis under eco-friendly reaction ***,a novel framework 1 was synthesized,exhibiting 1D channels with the size of 4.6 A×9.6 A and high solvent/p H/thermal stability.A stable framework allows it to encapsulate Cu nanoparticles(NPs)to form Cu NPs@1-x(x=1,2,3,and 4)with varying loading amounts of Cu NPs at 2.0 wt%,3.0 wt%,4.0 wt%,and 6.0 wt%,*** NPs@1-3 could selectively catalyze the reaction from THIQ to DHIQ with a high selectivity of 98%and a recorded turnover frequency(TOF)of 22.1 h-1under eco-friendly mild *** corresponding catalytic activity can maintain at least five recyclings and can be further applied to gram-scale ***,the efficient preparation of DHIQ catalyzed by Cu NPs@1-3 could be realized even under air ***,the anticancer molecule precursor synthesis of 6,7-dimethoxy-3,4-dihydroisoquinoline was also selectively catalyzed by Cu NPs@*** investigations revealed that high catalytic performance can be attributed to the stable framework and the synergistic catalytic effect of the loaded Cu NPs and Co metal *** importantly,this work represents the first example of MOF catalysts for selectively thermo-catalytic DHIQ synthesis and demonstrates a simple approach to obtain efficient catalysts for selective oxydehydrogenation in the production of unsaturated compounds.

关键词： metal-organic frameworks Cu NPs@MOFs 3 4-dihydroisoquinoline selective oxydehydrogenation synergistic catalysis

enhancing Multicriteria-Based Recommendations by Alleviating scalability and sparsity Issues Using Collaborative Denoising Autoencoder

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Computers, Materials & Continua 2024年第2期78卷 2269-2286页

作者： s.Abinaya K.Uttej Kumar school of Computer science&engineering Vellore Institute of TechnologyChennaiTamilnadu600127India

A Recommender system(Rs)is a crucial part of several firms,particularly those involved in *** conventional Rs,a user may only offer a single rating for an item-that is insufficient to perceive consumer ***,businesses in industries like e-learning and tourism enable customers to rate a product using a variety of factors to comprehend customers’*** the other hand,the collaborative filtering(CF)algorithm utilizing Autoencoder(Ae)is seen to be effective in identifying user-interested ***,the cost of these computations increases nonlinearly as the number of items and users *** triumph over the issues,a novel expanded stacked autoencoder(esAe)with Kernel Fuzzy C-Means Clustering(KFCM)technique is proposed with two *** the first phase of offline,the sparse multicriteria rating matrix is smoothened to a complete matrix by predicting the users’intact rating by the esAe approach and users are clustered using the KFCM *** the next phase of online,the top-N recommendation prediction is made by the esAe approach involving only the most similar user from multiple *** the esAe_KFCM model upgrades the prediction accuracy of 98.2%in Top-N recommendation with a minimized recommendation generation *** experimental check on the Yahoo!Movies(YM)movie dataset and TripAdvisor(TA)travel dataset confirmed that the esAe_KFCM model constantly outperforms conventional Rs algorithms on a variety of assessment measures.

关键词： Recommender systems multicriteria rating collaborative filtering sparsity issue scalability issue stacked-autoencoder Kernel Fuzzy C-Means Clustering

Origins of the problematic e in seIR epidemic models

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Infectious Disease Modelling 2024年第3期9卷 673-679页

作者： Donald s.Burke Distinguished University Professor emeritus of Health science and Policy Department of EpidemiologySchool of Public HealthUniversity of PittsburghUSA

During the COVID-19 pandemic,over one thousand papers were published on“susceptible-exposed-Infectious-Removed”(seIR)epidemic computational *** english word“exposed”in its vernacular and public health usage means a state of having been in contact with an infectious individual,but not necessarily *** contrast,the term“exposed”in seIR modeling usage typically stands for a state of already being infected but not yet being infectious to others,a state more properly termed“latently infected.”In public health language,“exposed”means possibly infected,yet in seIR modeling language,“exposed”means already *** paper retraces the conceptual and mathematical origins of this terminological disconnect and concludes that epidemic modelers should consider using the“sLIR”notational short-hand(L for Latent)instead of seIR.

关键词： seIR model exposed Latent infection History Notation