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Microsystems & Nanoengineering 2021年第6期7卷 45-70页

作者： Jens Ducrée School of Physical Sciences Dublin City UniversityDublinIreland

Current,application-driven trends towards larger-scale integration(LSI)of microfluidic systems for comprehensive assay automation and multiplexing pose significant technological and economical challenges to *** virtue of their intrinsic capability for powerful sample preparation,centrifugal systems have attracted significant interest in academia and business since the early *** review models common,rotationally controlled valving schemes at the heart of such“Lab-on-a-Disc”(LoaD)platforms to predict critical spin rates and reliability of flow control which mainly depend on geometries,location and liquid volumes to be processed,and their experimental *** absence of larger-scale manufacturing facilities during product development,the method presented here facilitates efficient simulation tools for virtual prototyping and characterization and algorithmic design optimization according to key performance *** virtual in silico approach thus significantly accelerates,de-risks and lowers costs along the critical advancement from idea,layout,fluidic testing,bioanalytical validation,and scale-up to commercial mass manufacture.

关键词： centrifugal advancement modeling

New DySrAlO_4 Compound Synthesis and Formation Process Correlations for LnSrAlO_4(Ln=Nd,Gd,Dy) Series

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Acta Metallurgica Sinica(english Letters) 2016年第5期29卷 450-456页

作者： e.A.Tugova New Inorganic Materials Laboratory Ioffe Institute

For the first time, DySrA104 of K2NiF4-type structure was synthesized. The parameters of DySrA104 ele- mentary unit cell are determined as follows： a = 0.368 （4） nm, c = 1.229 （2） nm, V = 0.166 （4） nm3. The research of the complex aluminates ZnSrA104 （Ln = Nd, Gd, Dy） solid-state process demonstrated the change of the formation mecha- nism among LnSrA104 （Ln = Nd, Gd, Dy） series from DySrA104 oxide. The performed analysis provided a possibility to realize why chemists couldn＇t get DySrA104 for a long period of time.

关键词： Rare earths Oxide materials K2NiF4-type structure Solid-state reactions Phase formation

Multi-revolution low-thrust trajectory optimization using symplectic methods

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Science China(Technological Sciences) 2020年第3期63卷 506-519页

作者： e ZhiBo GUZZeTTI Davide School of Aerospace engineering Tsinghua UniversityBeijing 100084China Department of Aerospace engineering Auburn UniversityAuburn AL 36849USA

Optimization of low-thrust trajectories that involve a larger number of orbit revolutions is considered as a challenging *** paper describes a high-precision symplectic method and optimization techniques to solve the minimum-energy low-thrust multi-revolution orbit transfer problem. First, the optimal orbit transfer problem is posed as a constrained nonlinear optimal control problem. Then, the constrained nonlinear optimal control problem is converted into an equivalent linear quadratic form near a reference solution. The reference solution is updated iteratively by solving a sequence of linear-quadratic optimal control sub-problems, until convergence. each sub-problem is solved via a symplectic method in discrete form. To facilitate the convergence of the algorithm, the spacecraft dynamics are expressed via modified equinoctial elements. Interpolating the non-singular equinoctial orbital elements and the spacecraft mass between the initial point and end point is proven beneficial to accelerate the convergence process. Numerical examples reveal that the proposed method displays high accuracy and efficiency.

关键词： low-thrust trajectory optimization symplectic method multi-revolution transfers

Blast injury risks to humans within a military trench

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Defence Technology（防务技术） 2024年第10期40卷 91-104页

作者： Idan e.edri National Building Research Institute Technion-Israel Institute of TechnologyTechnion CityHaifa 32000Israel

In land warfare,trenches serve as vital defensive fortifications,offering protection to soldiers while engaging in ***,despite their protective function,soldiers often sustain injuries within these *** lack of corresponding blast data alongside empirical injury reports presents a significant knowledge gap,particularly concerning the blast pressures propagating within trench spaces following nearby *** absence hinders the correlation between blast parameters,trench geometry,and reported injury cases,limiting our understanding of blast-related risks within *** paper addresses the critical aspect of blast propagation within trench systems,essential for evaluating potential blast injury risks to individuals within these *** advanced computational fluid dynamics(CFD)simulations,the study comprehensively investigates blast injury risks resulting from explosions near military *** a sophisticated computational model,the research analyzes the dynamic blast effects within trenches,considering both geometrical parameters and blast characteristics influenced by explosive weight and scaled *** numerical simulations yield valuable insights into the impact of these parameters on blast injury risks,particularly focusing on eardrum rupture,lung injury,and traumatic brain injury levels within the *** findings elucidate distinct patterns of high-risk zones,highlighting unique characteristics of internal explosions due to confinement and venting dynamics along the *** study underscores the significance of detailed numerical modeling in assessing blast injury risks and provides a novel knowledge base for understanding risks associated with explosives detonating near military *** insights gained contribute to enhancing safety measures in both military and civilian contexts exposed to blast events near trench structures.

关键词： Trench Blast Injury risk eardrum rupture Lung injury Traumatic brain injury

A comprehensive study for mass attenuation coefficients of different parts of the human body through Monte Carlo methods

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Nuclear Science and Techniques 2016年第3期27卷 31-39页

作者： e.e.ermis F.B.Pilicer e.Pilicer C.Celiktas Physics Department Faculty of ScienceEge University Physics Department Faculty of Arts and ScienceUludag University

The gamma-ray mass attenuation coefficients of blood,bone,lung,eye lens,adipose,tissue,muscle,brain and skin were calculated at different energies(60,80,150,400,500,600,1000,1250,1500,and 2000 keV) by various theoretical methods such as FLUKA,GeANT4 Monte Carlo(MC) methods and XCOM program in this *** coefficients were also compared with the National Institute of Standards and Technology(NIST) *** results were highly in accordance with each other and NIST *** results showed that FLUKA was quite convenient in comparison to GeANT4 in the calculation of the mass attenuation coefficients of the used human body samples for low-energy photons(60,80,and 150 keV) when compared with the NIST values.

关键词：质量衰减系数蒙特卡洛方法 Geant4 部位 NIST 美国国家标准能量计算眼晶状体

Photoluminescence properties of eu3+-doped MgAl2O4 nanoparticles in various surrounding media

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Journal of Rare earths 2019年第8期37卷 806-811,I0001页

作者： I.e.Kolesnikov e.V.Golyeva e.V.Borisov e.Yu Kolesnikov e.Lahderanta A.V.Kurochkin M.D.Mikhailov St.Petersburg State University St.PetersburgRussia Lappeenranta University of Technology LUT LappeenrantaFinland Peter the Great St.Petersburg Polytechnic University St.PetersburgRussia Scientific and Technological Institute of Optical Material Science VNTs S.I.Vavilov State Optical InstituteSt.PetersburgRussia Volga State University of Technology Yoshkar-OlaRussia

eu3+-doped MgAl2O4 nanoparticles were prepared by modified Pechini method.X-ray diffraction analysis shows pure tetragonal spinel phase without any *** average size of synthesized nanoparticles was determined to be about 50-60 nm using scanning electron microscopy and static light scattering *** and excitation spectra as well as lifetimes of MgAl2O4:eu3+ nanophosphors were explored in surrounding media with different refractive *** medium does not affect luminescence bands position,whereas 5D0 lifetime monotonically decreases along with increase of medium refractive *** of surrounding media on radiative and nonradiative decay rates,which were calculated using 4f-4f intensity theory,was studied and *** factor of prepared nanoparticles is defined using both radiative and observed lifetimes.

关键词： eu3+ Nanoparticles Filling factor Luminescence Lifetime Rare earths

Protection of Patients and the environment Through Optimization of Radiological Safety in Kinshasa Hospitals in the DRC: Proposals for Pedagogical and Didactic Remediation in the Learning Process at Higher and University Levels for the Optimization and Sustainability of Radiation Protection

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Journal of Biosciences and Medicines 2025年第1期13卷 132-144页

作者： Minga Barthelemy Bope Kwete Pembi Francy Pembi Luwaya Ndombasi Blanchard Ipende Lansikub Jean Sokomoy Nankwa Joséphine Mukadi Mukadi Jules Thomas Babena Bal’nsong Timothée Kapia Patrice Milambo Binkedi Ngoma Richard Mbiango Mabanza Francine Mayunga Ndakama Célestin Omombo Ngongo Timothée Nkwadi Katolo Adolphe Ngongo Mulemba Tchite Aya Nkole Benjamin Kafinga Luzolo emery Masandi Milondo Alphonse Community Health Higher Institute of Medical Technology Kinshasa Democratic Republic of the Congo Department of Occupational Hygiene Safety and Environmental Management Higher Institute of Medical Technology Kinshasa Democratic Republic of the Congo Department of Occupational Hygiene Safety and Environmental Management Higher Institute of Health Sciences of the Red Cross Kinshasa Democratic Republic of the Congo Faculty of Pedagogy and Didactics of Disciplines National Pedagogical University Kinshasa Democratic Republic of the Congo

The purpose of this research was to propose pedagogical and didactic strategies for teaching radiation protection at higher education and university levels, with the aim of optimizing radiological safety in the Democratic Republic of Congo (DRC). This was done after evaluating the implementation of protective measures against the harmful effects of X-rays in conventional radiology in Kinshasa hospitals. To achieve this, we conducted a survey in 23 Kinshasa hospitals with a sample of 400 health professionals, including 100 radiologists, to assess the level of implementation of radiation protection principles in order to propose pedagogical and didactic remediation in initial training where necessary. In addition to interviewing the respondents, we collected radiophysical parameters to evaluate the degree of irradiation in pediatric and adult radiology services in Kinshasa hospitals. After analyzing the data, the following results were recorded: the surveyed health personnel reported that more than 40% of requested radiology examinations are not justified. eleven services were found to be highly irradiating in pediatrics (48%) and two radiology services in adults (9%). Finally, all surveyed radiologist health personnel in Kinshasa do not know how to evaluate the degree of irradiation in their services. In light of these results, we proposed pedagogical and didactic remediation in radiation protection teaching during initial training to enable future health professionals to demonstrate competencies for optimizing radiological safety.

关键词： Optimization Radiation Protection Pedagogical and Didactic Remediation Radiological Safety

Three subspecies of Black-tailed Godwit share non-breeding sites in the world's largest river delta

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Avian Research 2025年第01期 1-10页

作者： Delip K.Das Wouter M.G.Vansteelant Bingrun Zhu Shariful Islam Naim Khandakar Marco van der Velde Chris J.Hassell Jesse R.Conklin Pierrick Bocher Jos C.e.W.Hooijmeijer Yvonne I.Verkuil Theunis Piersma Department of Zoology Faculty of Life and Earth Sciences Jagannath University Conservation ecology Group Groningen Institute for Evolutionary Life Sciences University of Groningen Bird eyes Centre for Global Ecological Change at the Faculties of Science & Engineering and Campus Fryslan University of Groningen Theoretical and Computational ecology Institute for Biodiversity and Ecosystem Dynamics University of Amsterdam Hunan Global Messenger Technology Co. Ltd Behavioural & Physiological ecology Groningen Institute for Evolutionary Life Sciences University of Groningen Global Flyway Network Littoral environnement et Sociétés UMR LIeNSs 7266 CNRS La Rochelle University NIOZ Royal Netherlands Institute for Sea Research Department of Coastal Systems

During the non-breeding season(September–April), Black-tailed Godwits(Limosa limosa) are commonly seen in coastal and inland wetlands of the Ganges-Brahmaputra-Meghna Delta in Bangladesh. We hypothesize that the Ganges-Brahmaputra-Meghna Delta, at the overlap between the Central Asian and east Asian–Australasian flyways, may host three subspecies that breed in disjunct areas of temperate and northern Asia: L. l. limosa, L. l. melanuroides, and L. l. bohaii. We used mitochondrial DNA(mt DNA) haplotype network and biometric analysis to determine subspecies in captured individuals, and deployed GPS–GSM transmitters to verify breeding areas of individuals with subspecies assignments. To test for differential habitat preferences, we sampled birds at two ecologically distinct habitats known to host the largest concentrations of non-breeding Black-tailed Godwits in Bangladesh: Nijhum Dweep National Park, a tidal coastal habitat with brackish water on the south-central coast, and Tanguar Haor(‘backmarsh'), a seasonal freshwater floodplain in the north. During the non-breeding seasons of 2021–2022 and 2022–2023, we sampled and measured 93 Black-tailed Godwits, 54 of which were equipped with GPS–GSM transmitters. Our mt DNA haplotype network analysis confirmed the presence of limosa, melanuroides, and bohaii subspecies at the study sites. Thus, indeed, Black-tailed Godwits subspecies, despite having distinct breeding ranges, exhibit(partially) overlapping non-breeding ranges in Asia. The subspecies composition differed significantly between sites, with limosa and bohaii dominating in Tanguar Haor and melanuroides in Nijhum Dweep. Of the 21 individuals that were tracked to their breeding grounds, 18 migrated to the expected breeding range of their respective subspecies. However, one bird with a limosa haplotype migrated to a known breeding area of bohaii, whereas two birds with melanuroides haplotypes migrated to the supposed breeding range of limosa. Therefore, while ecologic

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DNA Dynamics Studied Using the Homogeneous Balance Method

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Chinese Physics Letters 2012年第8期29卷 9-11页

作者： e.M.e.Zayed A.H.Arnous Mathematics Department Faculty of ScienceZagazig UniversityP.O.Box 44519ZagazigEgypt

We employ the homogeneous balance method to construct the traveling waves of the nonlinear vibrational dynamics modeling of *** new explicit forms of traveling waves are *** is shown that this method provides us with a powerful mathematical tool for solving nonlinear evolution equations in mathematical *** and weaknesses of the proposed method are discussed.

关键词： traveling nonlinear method

effect of Magnetic Field on a p-Type δ-Doped GaAs Layer

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Chinese Physics Letters 2010年第7期27卷 233-236页

作者： e. OZTURK Department of Physics Cumhuriyet University Sivas 58140 Turkey

The energy levels of holes in a p-type δ-doped GaAs structure under a magnetic field are theoretically calculated within the framework of the effective mass approximation for a uniform aceeptor distribution. The electronic structure is calculated by solving the Schrodinger and Poisson equations self-consistently. The effect of the magnetic field on the potential profile changes the degree of the confinement and localization, and thus this behavior can be used to study these systems in regions of interest, without the need to grow many different samples. It is found that the heavy-hole subbands contain many more energy states than the light-hole ones; the population of the heavy-hole levels represents approximately 91 % of all the carriers without magnetic field. With increasing magnetic field the total population of the heavy-holes increases and the number of filled states changes.

关键词： Magnetic field energy Fields Computers Political systems