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A new method for precise optical measurements of the sub-micron height of levitation of droplet clusters

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Particuology 2024年第4期87卷 173-178页

作者： Alexander A.Fedorets eduard E.Kolmakov Leonid A.Dombrovsky University of Tyumen 6 Volodarskogo StTyumen625003Russia Engineering Faculty Ariel UniversityP0.B.3407000ArielIsrael Joint Institute for High Temperatures 17A Krasnokazarmennaya StMoscow111116Russia

Droplet clusters levitating over the locally heated water surface are considered a very promising phe-nomenon of microfluidics for the potential use of the droplets as unique microreactors for microbio-logical experiments.A new optical method is suggested for precise measurements of the sub-micron levitation height of single *** method is based on the analysis of variable colors of the inter-ference halo around the *** the first time,it is possible to measure the extremely low downward velocity of droplets,which grow due to steam *** velocity was found to be 5-8 nm/*** height of the levitation of various droplets just before their coalescence with a layer of water was also *** measurements might be used for the verification of sophisticated models for the droplet levitation to be developed for a very thin layer of humid air under the droplet when the Knudsen effect should be taken into account.

关键词： Precise measurements Interferometric method Droplet cluster Levitation height

Double-check in Lizard Age Estimation:Use of Phalanx Bone and Keratin Claw Sheath Lamellas

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Asian Herpetological Research 2024年第1期15卷 59-61页

作者： eduard GALOYAN Natalia SOPILKO Anna KOVALYEVA Anna CHAMKINA A.N.Severtsov Institute of Ecology and Evolution Moscow 119071Russia Lomonosov Moscow State University Leninskie Gori 1Moscow 119991Russia

Dear Editor,The problem of age estimation in amphibians and reptiles with annual fluctuations of growth pattern has been considered to be mostly solved since the skeletochronological method was introduced(Kleinenberg and Smirina,1969).This method is based on counting the number of lines of arrested growth(LAGs)—cyclical growth marks that are usually formed annually and characterized by different optical aspects within the tubular bones.

关键词： estimation method usual

High temperature oxidation of inoculated high Si/SiMo ductile cast irons in air and combustion atmospheres

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China Foundry 2024年第5期21卷 555-562页

作者： Iuliana Stan Mihai Chisamera Robert Lascu Codrut Cariga eduard Stefan Stelian Stan Denisa Anca Iulian Riposan National University of Science and Technology POLITEHNICA Bucharest Materials Science and Engineering Faculty313 Splaiul IndependenteiSector 6060042 BucharestRomania

The present work aims to investigate the effect of heating temperature(400,600 and 800°C)and inoculating elements(Ca,Ca-Ba,Ca-RE)on oxidation behavior of ductile irons containing 5.25%Si and 4.8%Si-2.3%Mo in dry air and combustion gas containing water vapour(natural gas burning).The oxidation is influenced by the gas atmosphere type,the iron alloying system,and the inoculating elements depending on the heating *** weight gain increases from 0.001%-0.1%(400°C)to 0.05%-0.70%(600°C)and up to 0.10%-2.15%(800°C).No particular effects of the considered influencing factors are found when heating at 400°C,while at 600°C,mainly the oxidation gas atmosphere type shows a visible *** the highest heating temperature of 800°C,a limited increase of the weight gain is found for dry air atmosphere(up to 0.25%),but it drastically increases for combustion atmospheres(0.65%-2.15%).The water vapour presence in the combustion atmosphere is an important oxidising factor at 600-800°*** alloying system appears to influence the oxidation behavior mainly at a heating temperature of 800°C in the combustion atmosphere,as evidenced by the lower weight gain in 5.25%silicon cast *** effects of inoculating elements increase with the heating temperature,with Ca and Ba-FeSi inoculation generally showing better *** inoculated with CaRE-FeSi exhibit a higher degree of *** results are in good relationship with the previous reported data:Ca-Ba-inoculation system appears to be better than simple Ca for improving the graphite parameters,while RE-bearing inoculant negatively affects the compactness degree of graphite particles in high-Si ductile *** the lower compactness degree is typical for graphite nodules in high-Si ductile irons,which negatively affects the oxidation resistance,it is necessary to employ specific metallurgical treatments to improve nodule ***,in particular,is a potential method to achieve this improvement.

关键词： ductile iron spheroidal graphite Si/SiMo oxidation air/combustion atmospheres FeSiCaMgRE treatment Ca,Ca-Ba,Ca-RE inoculation structure characteristics

Resection and reconstruction in high-grade pancreatic head injuries

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World Journal of Gastrointestinal Surgery 2024年第5期16卷 1467-1469页

作者： Jake Krige eduard Jonas Andrew John Nicol Pradeep Harkson Navsaria HPB Surgery University of Cape Town Health Sciences FacultyCape Town 7925Western CapeSouth Africa Trauma Center Department of SurgeryGroote Schuur HospitalCape Town 7925Western CapeSouth Africa Department of Surgery Trauma CenterGroote Schuur HospCape Town 7925Western CapeSouth Africa

This study by Chui et al adds further important evidence in the treatment of highgrade pancreatic injuries and endorses the concept of the model of pancreatic trauma care designed to optimize treatment,minimize morbidity and enhance survival in patients with complex pancreatic *** the authors have demonstrated favorable outcomes based on their limited experience of 5 patients who underwent a pancreaticoduodenectomy(PD),including 2 patients who were“unstable”and did not have damage control surgery(DCS),we would caution against the general recommendations promoting index PD without DCS in“unstable”grade 5 pancreatic head injuries.

关键词： Pancreas Injury Surgery Pancreaticoduodenectomy

Revisiting the LQR Problem of Singular Systems

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IEEE/CAA Journal of Automatica Sinica 2024年第11期11卷 2236-2252页

作者： Komeil Nosrati Juri Belikov Aleksei Tepljakov eduard Petlenkov IEEE the Department of Computer Systems Tallinn University of Technology the Department of Software Science Tallinn University of Technology

In the development of linear quadratic regulator(LQR) algorithms, the Riccati equation approach offers two important characteristics——it is recursive and readily meets the existence condition. However, these attributes are applicable only to transformed singular systems, and the efficiency of the regulator may be undermined if constraints are violated in nonsingular versions. To address this gap, we introduce a direct approach to the LQR problem for linear singular systems, avoiding the need for any transformations and eliminating the need for regularity assumptions. To achieve this goal, we begin by formulating a quadratic cost function to derive the LQR algorithm through a penalized and weighted regression framework and then connect it to a constrained minimization problem using the Bellman's criterion. Then, we employ a dynamic programming strategy in a backward approach within a finite horizon to develop an LQR algorithm for the original system. To accomplish this, we address the stability and convergence analysis under the reachability and observability assumptions of a hypothetical system constructed by the pencil of augmented matrices and connected using the Hamiltonian diagonalization technique.

关键词： DC motor optimal control penalized weighted regression power system quadratic regulator singular system

40-meter-long REBCO tapes with critical current over 4,000 A/12 mm at 4.2 K and 13 T by advanced MOCVD

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Superconductivity 2024年第1期9卷 29-34页

作者： Mahesh Paidpilli Chirag Goel Bhabesh Sarangi Siwei Chen eduard Galstyan Jan Jaroszynski Griffin Bradford Dmytro Abraimov Venkat Selvamanickam Department of Mechanical Engineering Advanced Manufacturing InstituteTexas Center for SuperconductivityUniversity of HoustonHoustonTexasUSA AMPeers LLC HoustonTexasUSA National High Magnetic Field Laboratory TallahasseeFloridaUSA

REBa_(2)Cu_(3)O_(7−δ)(REBCO,RE=rare earth)tapes doped with 5%and 15%Zr have been scaled up to lengths more than 40 m in a pilot‐scale advanced metal organic chemical vapor deposition(A‐MOCVD)*** precursor compositions used for the long tapes were guided by a study of the influence of(Ba+dopant)/Cu content on the critical current density(Jc)of 5 and 15 mol.%Hf‐and Zr‐added tapes at 4.2 K and 13 *** 40‐mlong tapes exhibited a critical current(Ic)over 4,000 A/12 mm at 4.2 K and 13 T as well as over 1,400 A/12 mm at 20 K and 20 *** critical current densities of a 40‐m‐long tape doped with 5%Zr at 4.2 K measured at the National High Magnetic Field Laboratory(NHMFL)were>10 MAcm^(−2)and>5 MAcm^(−2)at 14 T and 30 T,respectively,which are over three times those of commercial REBCO *** infield Jc of 5%Zradded 40‐m‐long tapes was similar to those of previously‐reported high‐performance short samples made with 15%Zr or *** results demonstrate the excellent potential of A‐MOCVD for manufacturing high Ic REBCO tapes for use in ultrahigh‐field magnet applications.

关键词： High‐temperature superconductors MOCVD REBCO Critical current

调控铝在ITH沸石骨架中的位置以用于催化甲醇制烯烃

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Chinese Journal of Catalysis 2024年第1期56卷 114-121页

作者：范凯吴勤明刘烁孔海宇王森 eduard Kunkes Trees De Baerdemaeker Andrei-Nicolae Parvulescu Nils Bottke Toshiyuki Yokoi Dirk E.De Vos 孟祥举张维萍肖丰收浙江省应用化学重点实验室浙江大学化学系中国浙江杭州310028 浙江大学化学与生物工程学院中国浙江杭州310028 大连理工大学精细化工国家重点实验室中国辽宁大连116012 中国科学院山西煤炭化学研究所煤转化国家重点实验室中国山西太原030001 巴斯夫股份有限公司德国东京工业大学资源化学研究所日本鲁汶大学表面化学与催化中心比利时

随着低碳烯烃需求量的增加,甲醇制烯烃(MTO)成为由非石油资源制取低碳烯烃的关键技术,其中沸石由于具有可调节的酸度、有序的微孔结构和较好的择型性能而被广泛用作MTO反应催化剂.ITQ-13沸石(ITH拓扑结构)由于其独特的九元环结构在MTO... 详细信息

随着低碳烯烃需求量的增加,甲醇制烯烃(MTO)成为由非石油资源制取低碳烯烃的关键技术,其中沸石由于具有可调节的酸度、有序的微孔结构和较好的择型性能而被广泛用作MTO反应催化剂.ITQ-13沸石(ITH拓扑结构)由于其独特的九元环结构在MTO反应中表现出较好的丙烯选择性和反应寿命,引起了广泛关注.研究表明,分子筛的酸中心分布与MTO反应性能密切相关,因此,研究ITQ-13沸石中铝分布与MTO反应性能的关系,对进一步提升其MTO催化性能具有重要意义.本文分别以与ITH具有共同基本结构单元(双四元环,D4Rs)的LTA沸石(LTA-ITH)和薄水铝石(C-ITH)为铝源,合成了两类铝硅酸盐ITH沸石.X射线衍射、扫描电子显微镜以及氮气吸脱附表征结果表明,这两类分子筛具有相似的片状形貌和微孔性质.氨气程序升温脱附结果表明,具有相近硅铝比的两类ITH沸石具有相近的酸量.进一步采用27Al魔角旋转核磁共振(MAS NMR)、密度泛函理论计算和1-己烯裂解反应对两类ITH分子筛的铝分布进行研究.结果表明,两类分子筛具有不同的铝分布,LTA-ITH中有更多的铝进入ITH的正弦孔道与直孔道,而C-ITH中有更多的铝分布在交叉孔道.当前,研究者普遍认为MTO反应过程遵循双循环烃池机理,ITH交叉孔道由于具有较大的空间,相比于正弦孔道和直孔道,更有利于芳烃循环中间体的产生,从而有利于形成芳烃循环产物(乙烯),而正弦孔道和直孔道却更有利于烯烃循环过程,导致产生更多的丙烯.对两类ITH进行了MTO催化性能测试,结果表明,LTA-ITH比C-ITH表现出更高的丙烯选择性,并且表现出更高的丙烯与乙烯的比率,表明其烯烃循环过程得到加强,这与^(27)Al MAS NMR以及1-己烯裂解反应得到的结论一致,进一步证明ITH分子筛的铝分布得到有效调控.综上,本文阐明了ITH沸石中铝分布与其反应性能的关系,为调整沸石骨架中的Al位点提供一种新策略,为未来制备高效的MTO沸石基催化剂提供参考.

关键词：骨架铝分布硅铝ITH分子筛甲醇制烯烃铝核磁

Advances in technology for the laboratory diagnosis of individuals with HIV/AIDS coinfected with Mycobacterium tuberculosis

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Biosafety and Health 2024年第3期6卷 133-142页

作者： Jin Sun Xiaoxu Han Hongxia Yan Xin Zhang Taiyi Jiang Tong Zhang Hao Wu Grigory Kaminskiy Yingmin Ma eduard Karamov Bin Su Beijing Key Laboratory for HIV/AIDS Research Clinical and Research Center for Infectious DiseasesBeijing Youan HospitalCapital Medical UniversityBeijing 100069China State Health Organization Tula Regional Center for Control and Prevention of AIDS and Infectious Diseases Tula 300002Russia Department of Respiratory and Critical Care Medicine Beijing Youan HospitalCapital Medical UniversityBeijing 100069China Gamaleya National Research Centre for Epidemiology and Microbiology of the Ministry of Health of the Russian Federation Moscow 123098Russia

The high morbidity and mortality rate of individuals with human immunodeficiency virus(HIV)/acquired immunodeficiency syndrome(AIDS)coinfected with Mycobacterium tuberculosis(MTB)is a tough challenge for current global tuberculosis prevention and control ***/MTB coinfection is more complex than a single infection,and the interaction between the two diseases aggravates the deterioration caused by the disease,resulting in increased hospitalizations and *** screening and early diagnosis facilitate the timely initiation of anti-tuberculosis treatment in HIV/MTB coinfected individuals,thereby reducing transmission and the incidence of adverse *** date,pathogenic detection has remained the gold standard for diagnosing tuberculosis,but its sensitivity and specificity are greatly affected by the body's immune status,which limits its application in the diagnosis of HIV/MTB ***,immunology and molecular detection technology has developed *** detection technologies,such as interferon-γ release assays,interferon-gamma inducible protein 10,and GeneXpert MTB/RIF assay have overcome the limitations of traditional detection methods,significantly improved the sensitivity and specificity of tuberculosis diagnosis,and brought new hope to the detection of HIV/MTB *** this article,the principle,scope of application,and latest research progress of relevant detection methods are reviewed to provide a reference for the early diagnosis of HIV/MTB coinfection.

关键词： Human immunodeficiency virus(HIV) Mycobacterium tuberculosis(MTB)coinfection Mycobacterium tuberculosis(MTB) Early diagnosis

Investigation of the liquid recycle in the reactor cascade of an industrial scale ebullated bed hydrocracking unit

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Chinese Journal of Chemical Engineering 2019年第2期27卷 298-304页

作者： eduard Manek Juma Haydary Institute of Chemical and Environmental Engineering Faculty of Chemical and Food Technology Slovak University of Technology

One of the commercial means to convert heavy oil residue is hydrocracking in an ebullated bed. The ebullated bed reactor includes a complex gas–liquid–solid backmixed system which attracts the attention of many scientists and research groups. This work is aimed at the calculation of the internal recycle flow rate and understanding its effect on other parameters of the ebullated bed. Measured data were collected from an industrial scale residual hydrocracking unit consisting of a cascade of three ebullated bed reactors. A simplified block model of the ebullated bed reactors was created in Aspen Plus and fed with measured data. For reaction yield calculation, a lumped kinetic model was used. The model was verified by comparing experimental and calculated distillation curves as well as the calculated and measured reactor inlet temperature. Influence of the feed rate on the recycle ratio(recycle to feed flow rate) was estimated. A relation between the recycle flow rate, pump pressure difference and catalyst inventory has been identified. The recycle ratio also affects the temperature gradient along the reactor cascade. Influence of the recycle ratio on the temperature gradient decreased with the cascade member order.

关键词： Residual hydrocracking Ebullated bed reactor Liquid recycle Aspen Plus Simulation