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快速凝固中局部非平衡溶质截留的分析模型(英文)

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Transactions of Nonferrous Metals society of China 2012年第11期22卷 2749-2755页

作者： s. l. sobolev Institute of Problems of Chemical Physics Academy of Sciences of Russia Chernogolovka Moscow Region 142432 Russia

对二元合金快速凝固过程中的局部非平衡扩散模型(lNDM)进行改进。改进的模型考虑了熔体中溶质浓度和溶质通量流场与局部平衡的偏差。采用双曲函数扩散方程求得了熔体中溶质浓度和通量的准确解。结果表明,对任何固?液界面的动力学,当有... 详细信息

对二元合金快速凝固过程中的局部非平衡扩散模型(lNDM)进行改进。改进的模型考虑了熔体中溶质浓度和溶质通量流场与局部平衡的偏差。采用双曲函数扩散方程求得了熔体中溶质浓度和通量的准确解。结果表明,对任何固?液界面的动力学,当有效扩散系数DblNDM→0和在v→vDb发生完全溶质截留KlNDM(v)→1时,凝固过程将由扩散控制转变为完全的热控制。非扩散凝固和完全溶质截留的临界参数为在溶体中的扩散速度vDb,考察了不同界面动力学途径的溶质截留模型。

关键词：二元合金溶质截留快速凝固局部非平衡扩散双曲扩散方程溶质浓度溶质通量流场

Investigation of the effect of hydrocarbons and monoesters in the gelators’composition on the properties of edible oleogel

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Grain & Oil science and Technology 2024年第2期7卷 96-104页

作者： Yuliya Frolova Roman sobolev Varuzhan sarkisyan Alla Kochetkova Federal Research Centre of Nutrition Biotechnology and Food Safety2/14 Ustyinsky ProyezdMoscow 109240Russia

Natural wax gelators have different compositions of compounds(hydrocarbons,wax esters,free fatty alcohols,and free fatty acids),which results in oleogels with varying properties.To maintain a consistent composition,the individual components can be added to the original wax gelator.The content of hydrocarbons and wax esters greatly affects the structuring process of liquid edible oils with waxes.The aim of this study was to evaluate the possibility of modifying the properties of beeswax as a gelling agent by adding hydrocarbons or monoesters to obtain oleogels with specific properties.Various tests were conducted to assess the changes in the oleogel properties,such as color,microstructure,oil-binding capacity,thermal and textural properties.The research results have shown that the addition of the studied fractions has led to a significant change in all properties of oleogels.The initial size of oleogel crystals(7.29±1.80μm)changed after adding fractions,varying from 5.28μm to 12.58μm with hydrocarbons and from 9.95μm to 30.41μm with wax esters.The addition of 30%–50% hydrocarbons decreased the ability of the oleogels to bind oil and made them less firm compared to samples with 10%-20% hydrocarbons.Adding 10%-20% monoesters increased the firmness of the oleogels,but this indicator decreased when their content was increased to 50%.The obtained data indicate that hydrocarbons and wax esters can be used for targeted correction of the gelling properties of beeswax.

关键词： Oleogel Beeswax Hydrocarbons Wax monoesters Component composition of gelator Textural properties Food

A method to predict rockburst using temporal trend test and its application

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第3期16卷 909-923页

作者： Yarong Xue Zhenlei li Dazhao song Xueqiu He Honglei Wang Chao Zhou Jianqiang Chen Aleksei sobolev school of Civil and Resources Engineering University of Science and Technology BeijingBeijing100083China Zhong-an Academy of safety Engineering Beijing100083China China Energy Group Xinjiang Energy Co. LtdUrumqi830027China Khabarovsk Federal Research Center of the Far Eastern Branch of the Russian Academy of sciences(KhFRC FEB RAs) 51 Turgenev StreetKhabarovsk680000Russia

Rockbursts have become a significant hazard in underground mining,underscoring the need for a robust early warning model to ensure safety management.This study presents a novel approach for rockburst prediction,integrating the Mann-Kendall trend test(MKT)and multi-indices fusion to enable real-time and quantitative assessment of rockburst hazards.The methodology employed in this study involves the development of a comprehensive precursory index library for rockbursts.The MKT is then applied to analyze the real-time trend of each index,with adherence to rockburst characterization laws serving as the warning criterion.By employing a confusion matrix,the warning effectiveness of each index is assessed,enabling index preference determination.Ultimately,the integrated rockburst hazard index Q is derived through data fusion.The results demonstrate that the proposed model achieves a warning effectiveness of 0.563 for Q,surpassing the performance of any individual index.Moreover,the model’s adaptability and scalability are enhanced through periodic updates driven by actual field monitoring data,making it suitable for complex underground working environments.By providing an efficient and accurate basis for decision-making,the proposed model holds great potential for the prevention and control of rockbursts.It offers a valuable tool for enhancing safety measures in underground mining operations.

关键词： Rockburst Microseismicity Early warning Mann-Kendall trend test Confusion matrix Multi-indices fusion

In search of a pan-coronavirus vaccine:next-generation vaccine design and immune mechanisms

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Cellular & Molecular Immunology 2024年第2期21卷 103-118页

作者： s.Cankat M.U.Demael l.swadling Division of Infection and Immunity Institute of Immunity and TransplantationUniversity College LondonPears BuildingLondon NW32PPUK

Members of the coronaviridae family are endemic to human populations and have caused several epidemics and pandemics in recent history.In this review,we will discuss the feasibility of and progress toward the ultimate goal of creating a pan-coronavirus vaccine that can protect against infection and disease by all members of the coronavirus family.We will detail the unmet clinical need associated with the continued transmission of sARs-CoV-2,MERs-CoV and the four seasonal coronaviruses(HCoV-OC43,Nl63,HKU1 and 229E)in humans and the potential for future zoonotic coronaviruses.We will highlight how first-generation sARs-CoV-2 vaccines and natural history studies have greatly increased our understanding of effective antiviral immunity to coronaviruses and have informed next-generation vaccine design.We will then consider the ideal properties of a pan-coronavirus vaccine and propose a blueprint for the type of immunity that may offer cross-protection.Finally,we will describe a subset of the diverse technologies and novel approaches being pursued with the goal of developing broadly or universally protective vaccines for coronaviruses.

关键词： Vaccine Coronavirus Cross-reactive immunity Cross-protection Universal

Weighted Probability Density Estimator with Updated Bandwidths

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Journal of systems science & Complexity 2024年第2期37卷 886-906页

作者： WU Yi YU Wei WANG Xuejun PRAKAsA RAO B l s school of Big Data and Artificial Intelligence Chizhou UniversityChizhou 247000China school of Big Data and statistics Anhui UniversityHefei 230601China CR Rao Advanced Institute of Mathematics Statistics and Computer ScienceHyderabad 500046India

In this paper,the authors study a class of weighted version of probability density estimator.It is shown that the weighted estimator contains some existing estimators of probability density,no matter they are recursive or non-recursive.some statistical results including weak consistency,strong consistency,rate of strong consistency,and asymptotic normality are established under some mild conditions.Moreover,the random weighted estimator is also investigated.some numerical simulations and a real data analysis are presented to study the numerical performances of the estimators.

关键词： Asymptotic normality consistency numerical simulation probability density real data analysis updated bandwidths weighted estimator

Effect of radiative loss mechanisms on FIR thermometric parameters of Nd3+-doped lithium tellurite glasses

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Journal of Rare Earths 2024年第7期42卷 1250-1257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) Renato Archer Information Technology Center Institute of Physics of sao Carlos University of S?o Paulo

Nd3+-doped tellurite glasses are promising materials for thermometers based on the fluorescence intensity ratio（FIR） technique.Nevertheless,at high Nd3+concentrations,energy transfer（ET） processes such as optical reabsorption and cross-relaxation can affect the Nd3+emission,which has been little explored in the literature.Therefore,the present work investigated the use of Nd3+-doped tellurite glass(samples doped with Nd3+at 0.2 mol%,0.5 mol%,2.0 mol%,and 4.0 mol%) in fluorescence thermometers,in the temperature range from 299 to 371 K.The results indicate a strong dependence of the FIR parameters on the Nd3+concentration,due to changes in the emission band profiles caused by optical reabsorption of the Nd3+emissions and cross-relaxation processes.A decrease of the relative sensitivity of the ratio4F5/2→4I9/2/4F3/2→4I9/2is observed for samples doped with higher amounts of Nd3+.The maximum relative sensitivity at 299 K is 3.00%/K,which is the highest value among the reported Nd3+ions.

关键词： Fluorescence intensity ratio Judd-Ofelt Nd3+-doped tellurite glass Optical thermometry Rare earths

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砂岩破裂状态声发射梅尔倒谱系数判识方法

煤炭学报 2024年第2期49卷 753-766页

作者：何学秋杨菲李振雷李娜宋大钊王洪磊 sobolev Aleksei RAssKAZOV Igor 北京科技大学土木与资源工程学院北京100083 北京科技大学金属矿山高效开采与安全教育部重点实验室北京100083 俄罗斯科学院远东分院矿业研究院哈巴罗夫斯克680000

岩体结构破裂是严重制约矿山、地铁、隧道等地下空间工程建设及其安全运行的重要因素。实现对岩体结构破裂状态的识别是当下研究的热点与重点之一。为此,开展了不同条件的砂岩加载破坏实验,提取了加载全程的声发射梅尔倒谱系数及其波动... 详细信息

岩体结构破裂是严重制约矿山、地铁、隧道等地下空间工程建设及其安全运行的重要因素。实现对岩体结构破裂状态的识别是当下研究的热点与重点之一。为此,开展了不同条件的砂岩加载破坏实验,提取了加载全程的声发射梅尔倒谱系数及其波动差,研究了系数及其波动差在砂岩受载破坏全程的变化规律,分析了1号系数(一组声发射梅尔倒谱系数包括12个,1号系数指第1个声发射梅尔倒谱系数)及其波动差与砂岩破裂状态的相关性特征,基于此提出了砂岩破裂状态声发射梅尔倒谱系数判识方法,构建了判识准则并进行判识效果检验。结果表明:随载荷增加,1号系数整体上增大,系数及其离散性在破坏阶段显著增大并表现出显著的规律波动性特征;1号系数波动差具有阶段性变化特征,波动差的大小及其起伏变化可表征砂岩的破裂,波动差整体增大及突增的变化可反映砂岩非稳定变形和峰后破坏阶段的宏观破裂,波动差的突增幅度可反映砂岩破裂程度;声发射梅尔倒谱系数及其波动差对砂岩破裂表现出良好的响应特征,该特征受不同加载条件的影响较小,说明声发射梅尔倒谱系数在反映砂岩破裂上具有适用性;1号系数及其波动差与砂岩破裂状态具有较好相关性,该相关性可分为3个阶段,即1号系数及其波动差在砂岩微破裂阶段分布集中,在临近失稳破坏阶段分布范围急剧增大、整体值升高且出现高异常值,在峰后破坏阶段分布范围进一步增大、整体值更高、高异常值更多;利用1号系数的75%位点值和异常值、1号系数波动差的75%位点值和异常值构建了砂岩破裂状态判识准则,采用三分类模型混淆矩阵对判识准则的效果进行了检验,判识准确度和精准度分别为90.43%、94.45%。该成果可为其他种类煤岩的破裂状态识别提供借鉴,为煤岩失稳监测预警提供参考。

关键词：砂岩破裂状态声发射梅尔倒谱系数判识方法

Experimental implementation of phase triplicator gratings in a spatial light modulator

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Chinese Optics letters 2024年第2期22卷 64-69页

作者：高尚 María del Mar sánchez-lópez Ignacio Moreno Instituto de Bioingeniería Universidad Miguel HernándezElche 03202Spain Departamento de Física Aplicada Universidad Miguel HernándezElche 03202Spain Departamento de Ciencia de Materiales Óptica y Tec.Electr´onicaUniversidad Miguel HernándezElche 03202Spain

In this work,we compare different methods for implementing a triplicator,a phase grating that generates three equiintense diffraction orders.The design with optimal efficiency features a continuous phase profile,which cannot be easily reproduced,and is typically affected by quantization.We compare its performance with binary and sinusoidal phase profiles.We also analyze the effect of quantizing the phase levels.Finally,a random approach is adopted to eliminate the additional harmonic orders.In all cases,a liquid-crystal-on-silicon spatial light modulator is employed to experimentally verify and compare the different approaches.

关键词： diffraction gratings phase modulation triplicator spatial light modulators

Four late-type Galaxies with Double Radio lobes and Properties of such Galaxies

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Research in Astronomy and Astrophysics 2024年第4期24卷 84-90页

作者： Z.s.Yuan 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-type galaxies is not fully understood.More samples are desired for a thorough investigation and statistics.By utilizing the optical data from the newly released Dark Energy spectroscopic Instrument imaging surveys 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-type Galaxies with double Radio lobes(la GRls):J0217-3645,J0947+6220,J1412+3723 and J1736+5108.Including previously known la GRls,we confirm the correlation between radio power P_(1.4GHz)and stellar mass M_(*)of host galaxies.Most(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 sequence.We 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 lobes.Furthermore,the majority(31/36)of la GRls are either located in a galaxy group or displaying a disturbed morphology.We suggest that all of the galaxy mass,color and surrounding environment could play important roles in triggering radio lobes in late-type galaxies.

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