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Chinese Journal of Structural Chemistry 2011年第1期30卷 111-119页

作者： SAHN Onur bykgngr orhan ALbAyrAK igdem ODAbASOGLU Mustafa Department of Physics Faculty of Arts and SciencesOndokuz Mayls University Department of Science Education Sinop University Chemistry Programme Pamukkale University 20159 Denizli

The isomeric structures of（E）-1-[4-（2-hydroxy-5-methoxybenzylideneamino）-phenyl] ethanone（I） and（E）-1-[4-（2-hydroxy-4-methoxybenzylideneamino） phenyl]ethanone（Ⅱ） ,both C16H15NO3,have been determined using X-ray diffraction techniques and characterized by Ir,and their molecular structures have also been optimized at the b3LyP/6-31G（d,p） level using density functional theory（DFT） . The energetic behaviors of the title compounds in solvent media have been examined using b3LyP method with the 6-31G（d,p） basis set by applying the polarizable continuum model（PCM） . The total energies of the title compounds decrease with the increasing polarity of the solvent. In addition,DFT calculations of the title compounds＇ molecular electrostatic potentials（MEP） were performed at the b3LyP/6-31G（d,p） level of theory. X-ray study shows that the title compounds both have strong intramolecular O-H…N hydrogen bonds. The molecules of Ⅰ are linked into a one-dimensional framework structure by C-H…π interactions,while in Ⅱ,intermolecular π···π interactions result in the formation of infinite chains running along the [010].

关键词： crystal structure Schiff base DFT molecular electrostatic potential

4-Amino-3-(p-chlorophenyl)-5-(p-methoxybenzyl)-4H-1,2,4-triazole:X-ray and DFT-calculated Structures

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Chinese Journal of Structural Chemistry 2011年第5期30卷 731-737页

作者： SAHIN Onur KANTAr Cihan bEKIrCAN Olcay SASMAZ Selami büyükgüngr orhan Department of Physics Faculty of Arts and SciencesOndokuz Mayls University Department of Chemistry Rize University Karadeniz Teknik University

The title compound, 4-amino-3-（p-chlorophenyl）-5-（p-methoxybenzyl）-4H-1,2,4- triazole I , C16H15ClN4O）, has been determined using X-ray diffraction techniques and the molecular structure has also been optimized at the b3LyP/6-31 G（d, p） level using density functional theory （DFT）. The triazole ring exhibits dihedral angles of 41.61（15）o and 80.73（11）o with the phenyl rings. The molecules are linked principally by N–H…N hydrogen bonds involving the amino NH2 group and a triazole N atom, forming C（5） chains which are further linked to give a two-dimensional network of molecules. The N–H…N hydrogen bonding is supported by C–H…N hydrogen bond and C–H…π interaction. Intermolecular N–H…N and C–H…N hydrogen bonds produce r22（9）, r44（10） and r44（20） rings.

关键词： crystal structure chlorophenyl triazole hydrogen bonds

Synthesis, Crystal and Molecular Structure and biological Activity of Dimethyl Trans-3-(2-bromophenyl)-2-methylisoxazolidine-4,5-dicarboxylate

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Chinese Journal of Structural Chemistry 2012年第9期31卷 1251-1262页

作者： yÜKSEKTEPE Çigdem ÖZKAN Hamdi yAVUZ Serkan yANMAZ Volkan DISLI Ali bÜyÜkgÜngÖr orhan Department of Physics Faculty of ScienceCankiri Karatekin University Department of Chemistry Faculty of ScienceCankiri Karatekin University Department of Chemistry Faculty of Arts and SciencesGazi University Department of Physics Faculty of Arts and SciencesOndokuz Mayis University

The compound of dimethyl trans-3-（2-bromophenyl）-2-methylisoxazolidine-4,5-dicarboxylate has been synthesized and characterized by Ir, 1H-NMr, 13C-NMr, 2D-NMr （COSy, NOESy, HMQC, HMbC） and UV-vis. spectroscopy techniques and single-crystal X-ray diffraction （XrD）. The biological activities of the title compound have been investigated in detail. The new compound crystallizes in monoclinic, space group C2/c with a = 26.9263（10）, b = 7.0970（2）, c = 19.8554（7）？, and β = 126.630（2）. In addition to the single crystal structure, the molecular geometry, vibrational frequencies, chemical shifts, molecular electrostatic potential and frontier molecular orbital analysis of the title compound in the ground state have been calculated by Density Functional Theory （DFT） method.

关键词： ab initio calculations isoxazolidine spectroscopy X-ray structure determination

Design of a large-scale model for wind tunnel test of a multiadaptive flap concept

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Chinese Journal of Aeronautics 2024年第2期37卷 58-80页

作者： Mürüvvet Sinem SICIM DEMIrCI rosario PECOrA Metin orhan KAyA Aeronautical Engineering Department Istanbul Technical UniversityIstanbulTurkey Industrial Engineering Department University of Naples Federico IINapoliItaly

The design and application of morphing systems are ongoing issues compelling the aviation *** Clean Sky-program represents the most significant aeronautical research ever launched in Europe on advanced technologies for greening next-generation *** primary purpose of the program is to develop new concepts aimed at decreasing the effects of aviation on the environment,increasing reliability,and promoting eco-friendly *** ambitions are pursued through research on enabling technologies fostering noise and gas emissions reduction,mainly by improving aircraft aerodynamic *** the Clean Sky framework,a multimodal morphing flap device was designed based on tight industrial requirements and tailored for large civil aircraft *** flap is deployed in one unique setting,and its cross section is morphed differently in take-off and landing to get the necessary extra lift for the specific flight ***,during the cruise,the tip of the flap is deflected for load control and induced drag *** manufacturing the first flap prototype,a high-speed(Ma=0.3),large-scale test campaign(geometric scale factor 1:3)was deemed necessary to validate the performance improvements brought by this novel system at the aircraft *** the other hand,the geometrical scaling of the flap prototype was considered impracticable due to the unscalability of the embedded mechanisms and actuators for shape ***,a new architecture was conceived for the flap model to comply with the scaled dimensions requirements,withstand the relevant loads expected during the wind tunnel tests and emulate the shape transition capabilities of the true-scale *** strategies were developed to effectively morph the model during wind tunnel tests while ensuring the robustness of each morphed configuration and maintaining adequate stiffness levels to prevent undesirable deviations from the intended aerodynamic ***,

关键词： Morphing structures Smart aircraft Morphing flap Adaptive systems Finger-like ribs Wind tunnel tests Large-scale morphing archi-tectures Variable camber airfoil

Perturbing the Stable Accretion Disk in Kerr and 4D Einstein-Gauss-bonnet Gravities:Comprehensive Analysis of Instabilities and Dynamics

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research in Astronomy and Astrophysics 2024年第8期24卷 1-19页

作者： orhan Donmez College of Engineering and Technology American University of the Middle EastEgaila 54200Kuwait

The study of a disturbed accretion disk holds great significance in the realm of astrophysics,as such events play a crucial role in revealing the nature of disk structure,the release of energy,and the generation of shock ***,they can help explain the causes of X-ray emissions observed in black hole accretion disk *** this paper,we perturb the stable disk formed by spherical accretion around Kerr and Einstein-Gauss-bonnet(EGb)black *** perturbation reveals one-and two-armed spiral shock waves around the black *** find a strong connection between these waves and the black hole spin parameter(a/M)and the EGb coupling constant(α).Specifically,we find that asαincreases in the negative direction,the dynamics of the disk and the waves become more ***,we observe that the angular momentum of the perturbing matter significantly affects mass accretion and the oscillation of the arising shock *** allows us to observe changes in QPO frequencies,particularly,perturbations with angular momentum matching the observed C-type low-frequency QPOs of the GrS 1915+105 ***,we conclude that the possibility of the occurrence of shock waves within the vicinity of GrS 1915+105 is substantial.

关键词： accretion-accretion disks-black hole physics-hydrodynamics-shock waves-X-rays binaries

Developmental impacts and toxicological hallmarks of silver nanoparticles across diverse biological models

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Environmental Science and Ecotechnology 2024年第3期19卷 60-79页

作者： yán Wāng yapeng Han De-Xiang Xu Department of Toxicology School of Public Health&Key Laboratory of Environmental Toxicology of Anhui Higher Education InstitutesAnhui Medical UniversityHefei230032China

Silver nanoparticles(AgNPs),revered for their antimicrobial prowess,have become ubiquitous in a range of products,from biomedical equipment to food ***,amidst their rising popularity,concerns loom over their possible detrimental effects on fetal development and subsequent adult *** review delves into the developmental toxicity of AgNPs across diverse models,from aquatic species like zebrafish and catfish to mammalian rodents and in vitro embryonic stem *** focus encompasses the fate of AgNPs in different contexts,elucidating associated hazardous results such as embryotoxicity and adverse pregnancy ***,we scrutinize the enduring adverse impacts on offspring,spanning impaired neurobehavior function,reproductive disorders,cardiopulmonary lesions,and *** hallmarks of developmental harm are identified,encompassing redox imbalances,inflammatory cascades,DNA damage,and mitochondrial ***,we explore potential explanations,linking immunoregulatory dysfunction and disrupted epigenetic modifications to AgNPsinduced developmental *** substantial progress,our understanding of the developmental risks posed by AgNPs remains incomplete,underscoring the urgency of further research in this critical area.

关键词： Silver nanoparticles(AgNPs) Developmental toxicity Maternal exposure Fetal development redox imbalance Mitochondrial dysfunction

Weakly Supervised Object Localization with background Suppression Erasing for Art Authentication and Copyright Protection

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Machine Intelligence research 2024年第1期21卷 89-103页

作者： Chaojie Wu Mingyang Li ying Gao Xinyan Xie Wing W.y.ng Ahmad Musyafa School of Computer Science and Engineering South China University of TechnologyGuangzhou 511442China Guangdong Provincial Key Laboratory of Artificial Intelligence in Medical Image Analysis and Application Guangdong Provincial People's HospitalGuangzhou 510180China

The problem of art forgery and infringement is becoming increasingly prominent,since diverse self-media contents with all kinds of art pieces are released on the Internet every *** art paintings,object detection and localization provide an efficient and ef-fective means of art authentication and copyright ***,the acquisition of a precise detector requires large amounts of ex-pensive pixel-level *** alleviate this,we propose a novel weakly supervised object localization(WSOL)with background su-perposition erasing(bSE),which recognizes objects with inexpensive image-level ***,integrated adversarial erasing(IAE)for vanilla convolutional neural network(CNN)dropouts the most discriminative region by leveraging high-level semantic ***,a background suppression module(bSM)limits the activation area of the IAE to the object region through a self-guidance ***,in the inference phase,we utilize the refined importance map(rIM)of middle features to obtain class-agnostic loc-alization *** experiments are conducted on paintings,CUb-200-2011 and ILSVrC to validate the effectiveness of our bSE.

关键词： Weakly supervised object localization erasing method deep learning computer vision art authentication and copyright protection

Jetting-based bioprinting:process,dispense physics,and applications

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bio-Design and Manufacturing 2024年第5期7卷 771-799页

作者： Wei Long ng Viktor Shkolnikov Singapore Centre for 3D Printing(SC3DP) School of Mechanical and Aerospace EngineeringNanyang Technological University(NTU)Singapore 639798Singapore HP Inc. Palo AltoCA 94304USA

Jetting-based bioprinting facilitates contactless drop-on-demand deposition of subnanoliter droplets at well-defined positions to control the spatial arrangement of cells,growth factors,drugs,and biomaterials in a highly automated layer-by-layer fabrication *** to its immense versatility,jetting-based bioprinting has been used for various applications,including tissue engineering and regenerative medicine,wound healing,and drug development.A lack of in-depth understanding exists in the processes that occur during jetting-based *** review paper will comprehensively discuss the physical considerations for bioinks and printing conditions used in jetting-based *** first present an overview of different jetting-based bioprinting techniques such as inkjet bioprinting,laser-induced forward transfer bioprinting,electrohydrodynamic jet bioprinting,acoustic bioprinting and microvalve ***,we provide an in-depth discussion of various considerations for bioink formulation relating to cell deposition,print chamber design,droplet formation and droplet ***,we highlight recent accomplishments in jetting-based *** present the advantages and challenges of each method,discuss considerations relating to cell viability and protein stability,and conclude by providing insights into future directions of jetting-based bioprinting.

关键词： 3D bioprinting biofabrication Jetting-based Dispense physics Machine learning

Changes in Calcareous Nannofossil Assemblages and Paleoenvironmental Interpretation of the Early Miocene Lice Formation, Kahramanmara? basin, Turkey, East Mediterranean

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Acta Geologica Sinica(English Edition) 2024年第4期98卷 1021-1034页

作者： Caner KAyAÖZEr Muazez Esra orhan Uğur TEMİZ yozgat bozok University DivanlıRoadYozgat 66900Turkey

This study investigated the calcareous nannofossil assemblages in detail from the early Miocene aged Lice Formation outcropping in the Kahramanmara? basin. The biostratigraphy of calcareous nannofossils was outlined and paleoenvironmental features determined. In 81 samples taken from three measured sections in the region, 17 calcareous nannofossil genus and 48 nannofossil species were identified. These calcareous nannofossil genus and species identified the Lice Formation as being in the CNM4 nannofossil biozone. The abundance and diversity of early Miocene calcareous nannofossil species varied in the measured sections, with the samples generally moderate-poor, apart from a few samples. The relative abundance of individuals of Cyclicargolithus floridanus, Coccolithus pelagicus, reticulofenestra hagii and Sphenolithus moriformis species, with paleoecological importance identified in the study region, indicate that in early Miocene times, the basin in which the Lice Formation deposited was meso-eutrophic with excess nutrient input, temperate and generally stable shallow marine conditions.

关键词： paleoecology nannofossil burdigalian East Mediterranean

Dysfunction of synaptic endocytic trafficking in Parkinson's disease

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Neural regeneration research 2024年第12期19卷 2649-2660页

作者： Xin yi ng Mian Cao Programme in Neuroscience and behavioural Disorders Duke-NUS Medical SchoolSingaporeSingapore Department of Physiology National University of SingaporeSingaporeSingapore

Parkinson's disease is characterized by the selective degeneration of dopamine neurons in the nigrostriatal pathway and dopamine deficiency in the *** precise reasons behind the specific degeneration of these dopamine neurons remain largely *** investigations have identified over 20 causative PArK genes and 90 genomic risk loci associated with both familial and sporadic Parkinson's ***,several of these genes are linked to the synaptic vesicle recycling process,particularly the clathrinmediated endocytosis *** suggests that impaired synaptic vesicle recycling might represent an early feature of Parkinson's disease,followed by axonal degeneration and the eventual loss of dopamine cell bodies in the midbrain via a"dying back"***,several new animal and cellular models with Parkinson's disease-linked mutations affecting the endocytic pathway have been created and extensively *** models faithfully recapitulate certain Parkinson's disease-like features at the animal,circuit,and cellular levels,and exhibit defects in synaptic membrane trafficking,further supporting the findings from human genetics and clinical *** this review,we will first summarize the cellular and molecular findings from the models of two Parkinson's disease-linked clathrin uncoating proteins:auxilin(DNAJC6/PArK19)and synaptojanin 1(SyNJ1/PArK20).The mouse models carrying these two PArK gene mutations phenocopy each other with specific dopamine terminal pathology and display a potent synergistic ***,we will delve into the involvement of several clathrin-mediated endocytosis-related proteins(GAK,endophilin A1,SAC2/INPP5 F,synaptotagmin-11),identified as Parkinson's disease risk factors through genome-wide association studies,in Parkinson's disease *** will also explore the direct or indirect roles of some common Parkinson's disease-linked proteins(alpha-synuclein(PArK1/4),Parkin(PArK2),and LrrK2(PArK

关键词： autophagy auxilin/PArK19 clathrin-mediated endocytosis dopamine neurons neurodegeneration nigrostriatal pathway Parkinson's disease synaptic vesicle recycling synaptojanin1/PArK20