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Frontiers of Environmental Science & Engineering 2020年第5期14卷 15-23页

作者： Wenlu Li john d.Fortner department of Chemical and Environmental Engineering Yale UniversityNew HavenCT 06520USA

Over the past few decades,engineered,(super)paramagnetic nanoparticles have drawn extensive research attention for a broad range of applications based on their tunable size and shape,surface chemistries,and magnetic *** review summaries our recent work on the synthesis,surface modification,and environmental application of(super)paramagnetic *** utilizing high-temperature thermo-decomposition methods,first,we have broadly demonstrated the synthesis of highly monodispersed,(super)paramagnetic nanoparticles,via the pyrolysis of metal carboxylate salts in an organic *** uniform magnetic nanoparticles with various size,composition,and shape can be precisely tuned by controlled reaction parameters,such as the initial precursors,heating rate,final reaction temperature,reaction time,and the *** materials can be further rendered water stable via functionalization with surface mono/bi-layer coating structure using a series of tunable ionic/non-ionic ***,we have demonstrated platform potential of these materials for heavy metal ions sensing,sorption,and separation from the aqueous phase.

关键词： Superparamagnetic nanoparticles Surface functionalization Environmental sensing Heavy metal ion sorption

C1C2 Wiring and Posttraumatic Atlantoaxial dislocation: An Effective and Cheap Surgical Procedure in a developing Country

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Surgical Science 2024年第5期15卷 357-370页

作者： Ibrahim dao Massimiliano Visocchi Salah Sow john Jabang Ousmane Ouattara Astride Somda Abdoulaye Sanou Elie dibloni Nassoum Arsène Tossou Narcisse Ouedraogo Frédéric Bako Massadiami Soulama Malick diallo Patrick Wendpouiré Hamed dakouré department of Neurosurgery University Hospital Souro Sanou Nazi Boni University Bobo Dioulasso Burkina Faso High Institute of Health Sciences Nazi Boni University Bobo Dioulasso Burkina Faso Military Hospital Colonel Major Tanguet Ouattara Bobo Dioulasso Burkina Faso Institute of Neurosurgery Craniovertebral Junction Surgery Unit School of Medicine Catholic University Rome Italy department of Radiology and Medical Imaging University Hospital Yalgado Ouedraogo Joseph Ki-Zerbo University Ouagadougou Burkina Faso department of Neurosurgery (Unit) Edward Francis Small Teaching Hospital Banjul Gambia department of Neurosurgery University Hospital Yalgado Ouedraogo Joseph Ki-Zerbo University Ouagadougou Burkina Faso department of Neurosurgery Military Hospital Capitaine Halassane Coulibaly Ouagadougou Burkina Faso department of Orthopedic Surgery University Hospital Souro Sanou Nazi Boni University Bobo Dioulasso Burkina Faso

Objectives: Atlantoaxial dislocation remains a rare and serious condition with a high preoperative and postoperative morbidity and mortality. Its successful surgical management is still challenging and gratifying for neurosurgeons. Several technics have been described such as wiring, trans articular screwing, C1C2 screwing with plate and screw introduced by Goel et al., and modified by insertion of polyaxially screw and rod many years later by Harms. Unavailability and expensiveness of upper cervical spine instrumentation device led us to C1C2 Wiring resulting in a good outcome. Finally, a quadriplegic patient with a more comfortable financial condition had ordered devices from abroad and benefit for Goel and Harms screwing technique and improved dramatically from ASIA A to ASIA E. Material and methods: This is a retrospective study of patients managed in our department by a same neurosurgeon from January 2019 to April 2024. Results: We defined 6 men and 1 woman with an average age of 33 years. Unrestrained driver in a rollover motor vehicle accident was most common. Only one patient was neurologically intact on admission. Neurovegetative disorders were noticed in one patient. dislocation was associated to a fracture of the dens in two patients. Three patients have been successfully operated with remarkable outcome, mostly from ASIA A to E. Conclusion: C1C2 dislocation is a serious condition and C1C2 Wiring represents an effective and cheaper technic. Therefore, this technic should deserve consideration above all in low incomes countries when screwing devices are not available. Seatbelt should be demanded for motor vehicle drivers and passengers.

关键词： Superior Cervical Spine dislocation Fracture Wiring Screwing Neurovegetative disorders

Computational Modeling of dual-Phase Ceramics with Finsler-Geometric Phase Field Mechanics

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Computer Modeling in Engineering & Sciences 2019年第8期120卷 333-350页

作者： john d.Clayton US ARL Impact Physics BranchAberdeen Proving GroundMD21005-5066USA

A theory invoking concepts from differential geometry of generalized Finsler space in conjunction with diffuse interface modeling is described and implemented in finite element(FE)simulations of dual-phase polycrystalline ceramic *** parameters accounting for fracture and other structural transformations,notably partial dislocation slip,twinning,or phase changes,are dimensionless entries of an internal state vector of generalized pseudo-Finsler *** investigated in computations are a boron carbide-titanium diboride(B4C-TiB2)composite and a diamond-silicon carbide(C-SiC)*** mechanisms-in addition to elasticity and cleavage fracture in grains of any phase-include restricted dislocation glide(TiB2 phase),deformation twinning(B4C and-SiC phases),and stress-induced amorphization(B4C phase).The metric tensor of generalized Finsler space is scaled conformally according to dilatation induced by cavitation or other fracture modes and densification induced by phase *** of pure shear consider various morphologies and lattice *** of microstructure on overall strength of each composite are *** B4C-TiB2,minor improvements in shear strength and ductility are observed with an increase in the second phase from 10 to 18%by volume,suggesting that residual stresses or larger-scale crack inhibition may be responsible for toughness gains reported *** diamond-SiC,a composite consisting of diamond crystals encapsulated in a nano-crystalline SiC matrix shows improved strength and ductility relative to a two-phase composite with isolated bulk SiC grains.

关键词： Micromechanics ceramic composites,Finsler space differential geometry phase field finite elements

Optimized CUdA Implementation to Improve the Performance of Bundle Adjustment Algorithm on GPUs

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Journal of Software Engineering and Applications 2024年第4期17卷 172-201页

作者： Pranay R. Kommera Suresh S. Muknahallipatna john E. McInroy department of Electrical Engineering and Computer Science University of Wyoming Laramie Wyoming USA

The 3d reconstruction pipeline uses the Bundle Adjustment algorithm to refine the camera and point parameters. The Bundle Adjustment algorithm is a compute-intensive algorithm, and many researchers have improved its performance by implementing the algorithm on GPUs. In the previous research work, “Improving Accuracy and Computational Burden of Bundle Adjustment Algorithm using GPUs,” the authors demonstrated first the Bundle Adjustment algorithmic performance improvement by reducing the mean square error using an additional radial distorting parameter and explicitly computed analytical derivatives and reducing the computational burden of the Bundle Adjustment algorithm using GPUs. The naïve implementation of the CUdA code, a speedup of 10× for the largest dataset of 13,678 cameras, 4,455,747 points, and 28,975,571 projections was achieved. In this paper, we present the optimization of the Bundle Adjustment algorithm CUdA code on GPUs to achieve higher speedup. We propose a new data memory layout for the parameters in the Bundle Adjustment algorithm, resulting in contiguous memory access. We demonstrate that it improves the memory throughput on the GPUs, thereby improving the overall performance. We also demonstrate an increase in the computational throughput of the algorithm by optimizing the CUdA kernels to utilize the GPU resources effectively. A comparative performance study of explicitly computing an algorithm parameter versus using the Jacobians instead is presented. In the previous work, the Bundle Adjustment algorithm failed to converge for certain datasets due to several block matrices of the cameras in the augmented normal equation, resulting in rank-deficient matrices. In this work, we identify the cameras that cause rank-deficient matrices and preprocess the datasets to ensure the convergence of the BA algorithm. Our optimized CUdA implementation achieves convergence of the Bundle Adjustment algorithm in around 22 seconds for the largest dataset compared

关键词： Scene Reconstruction Bundle Adjustment Levenberg-Marquardt Non-Linear Least Squares Memory Throughput Computational Throughput Contiguous Memory Access CUdA Optimization

Inverse analysis of laboratory data and observations for evaluation of backward erosion piping process

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Journal of Rock Mechanics and Geotechnical Engineering 2020年第5期12卷 1080-1092页

作者： Sige Peng john d.Rice School of Civil Engineering and Transportation South China University of TechnologyGuangzhou510640China department of Civil and Environmental Engineering Utah State UniversityLogan84322UTUSA

An inverse analysis procedure has been developed to interpret collected pore pressure data and observations during backward erosion piping(BEP)initiation and progression in sandy *** procedure has been applied to laboratory models designed to mimic the initiation and progression of BEP through a constricted vertical *** inverse analysis uses three-dimensional(3d)finite element method(FEM)to successively produce models of the hydraulic head regime surrounding progressive stages of BEP based on observations at the sample surface and pore pressure measurements obtained from the laboratory *** inverse analysis results in a series of 3d contour plots that represent the hydraulic-head regime at each stage of the BEP development,allowing for assessing the development of BEP mechanism as well as calculating the critical hydraulic conditions required for various BEP stages to initiate and *** of the results identified four significant stages of the piping process:(1)loosened zone initiation,(2)channel initiation and progression,(3)riser sand fluidization,and(4)loosened zone *** of the hydraulic head contour plots allows assessment of the critical hydraulic gradients needed to initiate and progress various components of the BEP development.

关键词： Backward erosion piping(BEP) Laboratory modeling Inverse analysis Finite element method(FEM) Soil loosening Critical gradient

Effect of p-d exchange with an itinerant carrier in a GaMnAs quantum dot

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Journal of Semiconductors 2013年第7期34卷 1-6页

作者： d.Lalitha A.john Peter department of Physics GTN College department of Physics Government Arts College

Hydrogenic acceptor binding energy as a function of dot radius in a GaMnAs/Ga_（0.6）Al_（0.4）As quantum dot is calculated including the exchange interaction of Mn alloy content with an itinerant *** are performed by varying its dot radius,for various Mn alloy contents in GaMnAs quantum dot within a single band effective mass approximation using variational *** spin polaronic energy of the acceptor impurity for different Mn^（2＋） is evaluated for different dot radii using a mean field theory in the presence of magnetic field *** magnetization is computed in the influence of magnetic field and the Mn *** effective g-factor of the valence band electron with the inclusion of effects of Mn ion impurities is found in the influence of the magnetic *** exchange coupling constant is calculated for various magnetic field *** results show that the p-d exchange interaction in the GaMnAs/Ga_（0.6）Al_（0.4）As quantum dot has a strong dependence on spatial confinement,effect of magnetic field strength and the Mn alloy *** results are in good agreement with the other investigators.

关键词： quantum dot acceptor diluted magnetic semiconductors

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A Room of His Own

中国翻译 1995年第2期 62-63页

作者： Mary E.potter

Unmistakable noises are coming throughmy bedroom wall. Now a scuffling, now abumping, a long, drawn-out scraping"john, are you moving furniture in there? A-gain?" I call. The wall muffles his "yes" butdoes not filter ... 详细信息

关键词： A Room of His Own

Two-photon polymerization lithography for imaging optics

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International Journal of Extreme Manufacturing 2024年第4期6卷 21-60页

作者： Hao Wang Cheng-Feng Pan Chi Li Kishan S Menghrajani Markus A Schmidt Aoling Li Fu Fan Yu Zhou Wang Zhang Hongtao Wang Parvathi Nair Suseela Nair john You En Chan Tomohiro Mori Yueqiang Hu Guangwei Hu Stefan A Maier Haoran Ren Huigao duan Joel K W Yang College of Mechanical and Vehicle Engineering Hunan UniversityChangsha 410082People's Republic of China Engineering Product development Singapore University of Technology and DesignSingapore 487372Singapore Greater Bay Area Institute for Innovation Hunan UniversityGuangzhou 511300People's Republic of China department of Electrical and Computer Engineering National University of Singapore4 Engineering Drive 3Singapore 117576Singapore School of Physics and Astronomy Faculty of ScienceMonash UniversityMelbourneVictoria 3800Australia Leibniz Institute of Photonic Technology 07745 JenaGermany Abbe Center of Photonics and Faculty of Physics FSU Jena07745 JenaGermany Otto Schott Institute of Material Research FSU Jena07745 JenaGermany Institute of Materials Research and Engineering A*STAR(Agency for Science Technology and Research)Singapore 138634Singapore Industrial Technology Center of Wakayama Prefecture Wakayama 6496261Japan School of Electrical and Electronic Engineering Nanyang Technological UniversitySingapore639798Singapore department of Physics Imperial College LondonLondon SW72AZUnited Kingdom

Optical imaging systems have greatly extended human visual capabilities,enabling the observation and understanding of diverse *** technologies span a broad spectrum of wavelengths from x-ray to radio frequencies and impact research activities and our daily *** glass lenses are fabricated through a series of complex processes,while polymers offer versatility and ease of ***,modern applications often require complex lens assemblies,driving the need for miniaturization and advanced designs with micro-and nanoscale features to surpass the capabilities of traditional fabrication ***-dimensional(3d)printing,or additive manufacturing,presents a solution to these challenges with benefits of rapid prototyping,customized geometries,and efficient production,particularly suited for miniaturized optical imaging *** 3d printing methods have demonstrated advantages over traditional counterparts,yet challenges remain in achieving nanoscale ***-photon polymerization lithography(TPL),a nanoscale 3d printing technique,enables the fabrication of intricate structures beyond the optical diffraction limit via the nonlinear process of two-photon absorption within liquid *** offers unprecedented abilities,***-free fabrication,micro-and nanoscale capabilities,and rapid prototyping of almost arbitrary complex 3d *** this review,we emphasize the importance of the criteria for optical performance evaluation of imaging devices,discuss material properties relevant to TPL,fabrication techniques,and highlight the application of TPL in optical *** the first panoramic review on this topic,it will equip researchers with foundational knowledge and recent advancements of TPL for imaging optics,promoting a deeper understanding of the *** leveraging on its high-resolution capability,extensive material range,and true 3d processing,alongside advances in materials,fabrication,and design,we en

关键词： two-photon polymerization lithography 3d printing additive manufacturing imaging optics and nanophotonics

A Standard of Excellence

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中国翻译 1995年第3期 61-62页

作者： Mary E. potter

My 14-year-old son, john, and I spotted thecoat simultaneously. It was hanging on a rack ata secondhand clothing store in Northampton,Mass., crammed in with shoddy trench coats andan assortment of sad, woollen overcoats—a roseamong thorns. While the other coats drooped, this onelooked as if it were holding itself up. The thick,black wool of the double-breasted chesterfieldwas soft and unworn, as though it had been pre-served in mothballs for years in dear old

关键词：盖茨比大衣普通名词英国历史美国小说生产厂家曼哈顿纽约市外交家再生

Gas-phase synthesis of Ti_(2)CCl_(2) enables an efficient catalyst for lithiumsulfur batteries

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The Innovation 2024年第1期5卷 33-40页

作者： Maoqiao Xiang Zihan Shen Jie Zheng Miao Song Qiya He Yafeng Yang Jiuyi Zhu Yuqi Geng Fen Yue Qinghua dong Yu Ge Rui Wang Jiake Wei Weiliang Wang Haiming Huang Huigang Zhang Qingshan Zhu Chuanfang john Zhang State Key Laboratory of Multiphase Complex Systems Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China School of Chemical Engineering University of the Chinese Academy of SciencesBeijing 100049China Innovation Academy for Green Manufacture Chinese Academy of SciencesBeijing 100190China China Nuclear Power Engineering Co. Ltd.117 West Third Ring RoadNorth SectionBeijing 100840China College of Materials Science&Engineering Sichuan UniversityChengdu 610065China State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China School of Physics Guangdong Province Key Laboratory of Display Material and TechnologyCenter for Neutron Science and TechnologySun Yat-sen UniversityGuangzhou 510275China Solid State Physics&Material Research Laboratory School of Physics and Materials ScienceGuangzhou UniversityGuangzhou 510006China

MXenes have aroused intensive enthusiasm because of their exotic properties and promising ***,to date,they are usually synthesized by etching *** synthetic technologies provides more opportunities for innovation and may extend unexplored ***,we report a bottom-up gas-phase synthesis of Cl-terminated MXene(Ti_(2)CCl_(2)).The gas-phase synthesis endows Ti_(2)CCl_(2) with unique surface chemistry,high phase purity,and excellent metallic conductivity,which can be used to accelerate polysulfide conversion kinetics and dramatically prolong the cyclability of Li-S ***-depth mechanistic analysis deciphers the origin of the formation of Ti_(2)CCl_(2) and offers a paradigm for tuning MXene chemical vapor *** brief,the gas-phase synthesis transforms the synthesis of MXenes and unlocks the hardly achieved potentials of MXenes.

关键词： synthesis phase lithium