Sample records for efficient shell strut

  1. Compression Dispersion Efficiency of Recycled Aggregate Concrete Struts At Different Load Concentration Ratios

    Dr. Rakesh Kumar, Dr.P.K Mehta,Devbrat Singh, Anup Kumar Pandey, Sarvesh Kumar


    Full Text Available Infrastructure development activities in India have increased many folds in recent times. This has resulted in increase in the demand of construction materials like cement, coarse aggregate, fine aggregate etc. Huge quantities of concrete wastes are produced due to demolition of old structures. If recycled aggregate from this waste is used for construction purpose, it will not only make the structures economical and eco-friendly butwill also solve the problem of waste disposal.Recycling old waste concrete by crushing and grading into coarse aggregates for use in new structural concrete is drawing the attention of engineers, environmentalists and researchers since last three decades. In this paper, an attempt has been made to study the compression dispersion behaviour of struts of natural coarse aggregate (NCA and recycle coarse aggregate (RCA at different load concentration ratio and aspect ratio. For the study, struts of 450 mm height and 75mm thickness with varying widths starting from 75mm to 450mm, using NCA and RCA concrete, were cast. The testing of struts was carriedout on loading frame of capacity 500 kN. The struts were tested to failure under in-plane compressive load applied through symmetrically placed steel plate (75×75×10 mm at top andbottom of the struts.

  2. Efficient stock piling of 40mm shells

    J. N. Nanda


    Full Text Available A problem was posed as to discuss efficient stock-piling of 40mm shells. There is, in fact no data from which emergency requirements can be deduced. A figure has been quoted by Army authorities that E rounds per month are required during an emergency. The size of the emergency stock pile will depend upon the difference of the normal peace time production, and also on the time taken for the crash programme of emergency production to come into fulfillment. In addition the delivery time from factories to the stock piles is also kept in view.

  3. Enhanced efficiency of a fluorescing nanoparticle with a silver shell

    Choy, Wallace C H; Chen Xuewen [Department of Electrical and Electronic Engineering, University of Hong Kong, Pokfulam Road (Hong Kong); He Sailing [Centre for Optical and Electromagnetic Research, Zhejiang University, Zhijingang campus, Hangzhou 310058 (China)], E-mail:


    Spontaneous emission (SE) rate and the fluorescence efficiency of a bare fluorescing nanoparticle (NP) and the NP with a silver nanoshell are analyzed rigorously by using a classical electromagnetic approach with the consideration of the nonlocal effect of the silver nano-shell. The dependences of the SE rate and the fluorescence efficiency on the core-shell structure are carefully studied and the physical interpretations of the results are addressed. The results show that the SE rate of a bare NP is much slower than that in the infinite medium by almost an order of magnitude and consequently the fluorescence efficiency is usually low. However, by encapsulating the NP with a silver shell, highly efficient fluorescence can be achieved as a result of a large Purcell enhancement and high out-coupling efficiency (OQE) for a well-designed core-shell structure. We also show that a higher SE rate may not offer a larger fluorescence efficiency since the fluorescence efficiency not only depends on the internal quantum yield but also the OQE.

  4. Jakarta Struts Pocket Reference

    Cavaness, Chuck


    Web tier frameworks have soared in popularity over the past year or so due to the increasing complexity of Java itself, and the need to get more work done with fewer resources. Developers who used to spend hours and hours writing low-level features can use a well-written framework to build the presentation tier so they start coding the "good stuff" sooner--the business logic at the core of the program. The Jakarta Struts Framework is one of the most popular presentation frameworks for building web applications with Java Servlet and JavaServer Pages (JSP) technologies. If you work with the St

  5. Computational simulation of multi-strut central lobed injection of hydrogen in a scramjet combustor

    Gautam Choubey


    Full Text Available Multi-strut injection is an approach to increase the overall performance of Scramjet while reducing the risk of thermal choking in a supersonic combustor. Hence computational simulation of Scramjet combustor at Mach 2.5 through multiple central lobed struts (three struts have been presented and discussed in the present research article. The geometry and model used here is slight modification of the DLR (German Aerospace Center scramjet model. Present results show that the presence of three struts injector improves the performance of scramjet combustor as compared to single strut injector. The combustion efficiency is also found to be highest in case of three strut fuel injection system. In order to validate the results, the numerical data for single strut injection is compared with experimental result which is taken from the literature.

  6. Efficient Finite Element Methods for Transient Analysis of Shells.


    Triangular Shell Element with Improved Membrane Interpolation," Communications in Applied Numerical Methods , in press 1985. Results of this work Applied Numerical Methods , to appear. G.R. Cowper, G.M. Lindberg and M.D. Olson (1970), "A Shallow Shell Finite Element of Triangular Shape," Int. J

  7. Efficient Finite Element Methods for Transient Nonlinear Analysis of Shells.


    governing equations for a beam based on shallow shell theory and the variational formulations which pertain in this context to displacement, hybrid, and...functions, respectively. Because the curvature is treated by shallow - shell theory , cf. Eqs. (1), all terms were integrated over the straight x-axis. Only

  8. Fuel/Air Mixing Characteristics of Strut Injections for Scramjet Combustor Applications (Postprint)


    regions, and drag will be increased, as suggested by Povinelli .26 Both the total pressure recovery and mixing efficiency for the forward-swept strut are...Experimental Study of Cavity-Strut Combustion in Supersonic Flow,” AIAA Paper 2007-5394, 2007. 26. Povinelli , L.A., “Aerodynamic Drag and Fuel Spreading

  9. 基于Struts 2的Web应用开发研究%Research on Web Application Development Based on Struts 2

    聂常红; 唐远强


    介绍Struts框架的体系结构,详细描述Struts 2的工作原理,并以登录模块开发为例,阐述Struts 2框架在Web应用开发中的具体应用,讨论Struts 2框架对中文乱码的处理以及对敏感JSP页面的保护访问。实践证明,使用Struts 2框架后,可极大地简化Web 应用系统的开发和部署,可快速高效地开发出企业级Web 应用程序,在系统可扩展性、可维护性和安全性等软件质量方面也有极大的提高。%Introduces the system structure of Struts framework, describes Struts 2 principle of work in details, and takes login module development as an example, expounds the Struts 2 framework in Web application development in the specific application. Discusses the Struts 2 framework processing of Chinese garbled and handling of sensitive to the protection of the JSP page visit. Practice has proved that, using the Struts 2 framework can simplify the Web application system development and deployment greatly, and it can develop the enterprise Web applications quickly and efficiently, meantime, the system which has been developed by using Struts 2 framework can also greatly improve the software quality, such as scalability, maintainability and security and so on.

  10. An Exploratory Study of Critical Factors Affecting the Efficiency of Sorting Techniques (Shell, Heap and Treap)

    Folorunso, Olusegun; Salako, Oluwatimilehin


    The efficiency of sorting techniques has a significant impact on the overall efficiency of a program. The efficiency of Shell, Heap and Treap sorting techniques in terms of both running time and memory usage was studied, experiments conducted and results subjected to factor analysis by SPSS. The study revealed the main factor affecting these sorting techniques was time taken to sort.

  11. Apache Struts MVC框架研究

    阚文第; 吴元杰; 祁明龙


    本文介绍了Web项目开发中应广泛用中的MVC设计模式,以及基于MVC的struts MVC.首先介绍了为什么使用MVC,然后深入探讨了struts MVC框架,以及struts与当前其他框架的比较,演示了struts MVC的工程实现.

  12. Amphiphilic core-shell nanoparticles containing dense polyethyleneimine shells for efficient delivery of microRNA to Kupffer cells.

    Liu, Zuojin; Niu, Dechao; Zhang, Junyong; Zhang, Wenfeng; Yao, Yuan; Li, Pei; Gong, Jianping


    Efficient and targeted delivery approach to transfer exogenous genes into macrophages is still a great challenge. Current gene delivery methods often result in low cellular uptake efficiency in vivo in some types of cells, especially for the Kupffer cells (KCs). In this article, we demonstrate that amphiphilic core-shell nanoparticles (NPs) consisting of well-defined hydrophobic poly(methyl methacrylate) (PMMA) cores and branched polyethyleneimine (PEI) shells (denoted as PEI@PMMA NPs) are efficient nanocarriers to deliver microRNA (miRNA)-loaded plasmid to the KCs. Average hydrodynamic diameter of PEI@ PMMA NPs was 279 nm with a narrow size distribution. The NPs also possessed positive surface charges up to +30 mV in water, thus enabling effective condensation of negatively charged plasmid DNA. Gel electrophoresis assay showed that the resultant PEI@PMMA NPs were able to completely condense miRNA plasmid at a weight ratio of 25:1 (N/P ratio equal to 45:1). The Cell Counting Kit-8 assay and flow cytometry results showed that the PEI@PMMA/miRNA NPs displayed low cytotoxicity and cell apoptosis activity against the KCs. The maximum cell transfection efficiency reached 34.7% after 48 hours, which is much higher than that obtained by using the commercial Lipofectamine™ 2000 (1.7%). Bio-transmission electron microscope observation revealed that the PEI@PMMA NPs were mainly distributed in the cytoplasm of the KCs. Furthermore, when compared to the control groups, the protein expression of target nuclear factor κB P65 was considerably inhibited (P<0.05) both in vitro and in vivo. These results demonstrate that the PEI@PMMA NPs with a unique amphiphilic core-shell nanostructure are promising nanocarriers for delivering miRNA plasmid to KCs.

  13. Amphiphilic core shell nanoparticles containing dense polyethyleneimine shells for efficient delivery of microRNA to Kupffer cells

    Liu Z


    Full Text Available Zuojin Liu,1,* Dechao Niu,2,3,* Junyong Zhang,1 Wenfeng Zhang,1 Yuan Yao,2 Pei Li,2 Jianping Gong1 1Department of Hepatobiliary Surgery, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, 2Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, 3Lab of Low-Dimensional Materials Chemistry, School of Materials Science and Engineering, East China University of Science and Technology, Shanghai, People’s Republic of China *These authors contributed equally to this work Abstract: Efficient and targeted delivery approach to transfer exogenous genes into macrophages is still a great challenge. Current gene delivery methods often result in low cellular uptake efficiency in vivo in some types of cells, especially for the Kupffer cells (KCs. In this article, we demonstrate that amphiphilic core–shell nanoparticles (NPs consisting of well-defined hydrophobic poly(methyl methacrylate (PMMA cores and branched polyethyleneimine (PEI shells (denoted as PEI@PMMA NPs are efficient nanocarriers to deliver microRNA (miRNA-loaded plasmid to the KCs. Average hydrodynamic diameter of PEI@PMMA NPs was 279 nm with a narrow size distribution. The NPs also possessed positive surface charges up to +30 mV in water, thus enabling effective condensation of negatively charged plasmid DNA. Gel electrophoresis assay showed that the resultant PEI@PMMA NPs were able to completely condense miRNA plasmid at a weight ratio of 25:1 (N/P ratio equal to 45:1. The Cell Counting Kit-8 assay and flow cytometry results showed that the PEI@PMMA/miRNA NPs displayed low cytotoxicity and cell apoptosis activity against the KCs. The maximum cell transfection efficiency reached 34.7% after 48 hours, which is much higher than that obtained by using the commercial Lipofectamine™ 2000 (1.7%. Bio-transmission electron microscope observation revealed that the PEI@PMMA NPs were mainly distributed in

  14. Core/shell quantum dot based luminescent solar concentrators with reduced reabsorption and enhanced efficiency.

    Coropceanu, Igor; Bawendi, Moungi G


    CdSe/CdS core/shell quantum dots (QDs) have been optimized toward luminescent solar concentration (LSC) applications. Systematically increasing the shell thickness continuously reduced reabsorption up to a factor of 45 for the thickest QDs studied (with ca. 14 monolayers of CdS) compared to the initial CdSe cores. Moreover, an improved synthetic method was developed that retains a high-fluorescence quantum yield, even for particles with the thickest shell volume, for which a quantum yield of 86% was measured in solution. These high quantum yield thick shell quantum dots were embedded in a polymer matrix, yielding highly transparent composites to serve as prototype LSCs, which exhibited an optical efficiency as high as 48%. A Monte Carlo simulation was developed to model LSC performance and to identify the major loss channels for LSCs incorporating the materials developed. The results of the simulation are in excellent agreement with the experimental data.

  15. Shell

    Harper, Catherine


    Susie MacMurray's Shell installation manifests in Pallant House Gallery, Chichester, like some pulsing exotica, a heavily-textured wall-paper, darkly decorative, heavily luxurious, broodingly present, with more than a hint of the uncanny or the gothic. A remarkable undertaking by an artist of significance, this work's life-span will be just one year, and then it will disappear, leaving no physical trace, but undoubtedly contributing in a much less tangible way to an already rich layering of n...

  16. Simulation and Experiment Research of Aerodynamic Performance of Small Axial Fans with Struts

    CHU Wei; LIN Peifeng; ZHANG Li; JIN Yingzi; WANG Yanping; Heuy Dong Kim; Toshiaki Setoguchi


    Interaction between rotor and struts has great effect on the performance of small axial fan systems.The small axial fan systems are selected as the studied objects in this paper,and four square struts are downstream of the rotor.The cross section of the struts is changed to the cylindrical shapes for the investigation:one is in the same hydranlic diameter as the square struts and another one is in the same cross section as the square struts.Influence of the shape of the struts on the static pressure characteristics,the internal flow and the sound emission of the small axial fans are studied.Standard K-ε turbulence model and SIMPLE algorithm are applied in the calculation of the steady fluid field,and the curves of the pressure rising against the flow rate are obtained,which demonstrates that the simulation results are in nice consistence with the experimental data.The steady calculation results are set as the initial field in the unsteady calculation.Large eddy simulation and PISO algorithm are used in the transient calculation,and the Ffowcs Wtlliams-Hawkings model is introduced to predict the sound level at the eight monitoring points.The research results show that:the static pressure coefficients of the fan with cylindrical struts increase by about 25% compared to the fan with square struts,and the efficiencies increase by about 28.6%.The research provides a theoretical guide for shape optimization and noise reduction of small axial fan with struts.

  17. Viscoelastic struts for vibration mitigation of FORTE

    Maly, Joseph R.; Butler, Thomas A.


    FORTE is a small satellite being developed by Los Alamos National Laboratory (LANL) and Sandia National Laboratories Albuquerque (SNLA). It will be placed into orbit via a Pegasus launch in 1996. Testing a full-scale engineering model of the structure using the proto- qualification, system-level vibration spectrum indicated that acceleration levels caused by structural resonances exceed component levels to which certain sensitive components had previously been qualified. Viscoelastic struts were designed to reduce response levels associated with these resonances by increasing the level of damping in key structural modes of the spacecraft. Four identical shear-lap struts were fabricated and installed between the two primary equipment decks. The struts were designed using a system finite element model (FEM) of the spacecraft, a component FEM of the strut, and measured viscoelastic properties. Direct complex stiffness testing was performed to characterize the frequency-dependent behavior of the struts, and these measured properties (shear modulus and loss factor) were used to represent the struts in the spacecraft model. System-level tests were repeated with the struts installed and the response power spectral densities at critical component locations were reduced by as much as 10 dB in the frequency range of interest.

  18. Si/PEDOT:PSS core/shell nanowire arrays for efficient hybrid solar cells.

    Lu, Wenhui; Wang, Chengwei; Yue, Wei; Chen, Liwei


    A solution filling and drying method has been demonstrated to fabricate Si/PEDOT:PSS core/shell nanowire arrays for hybrid solar cells. The hybrid core/shell nanowire arrays show excellent broadband anti-reflection, and resulting hybrid solar cells absorb about 88% of AM 1.5G photons in the 300-1100 nm range. The power conversion efficiency (PCE) of the hybrid solar cell reaches 6.35%, and is primarily limited by direct and indirect interfacial recombination of charge carriers.

  19. Highly efficient photocatalytic performance of graphene-ZnO quasi-shell-core composite material.

    Bu, Yuyu; Chen, Zhuoyuan; Li, Weibing; Hou, Baorong


    In the present paper, the graphene-ZnO composite with quasi-shell-core structure was successfully prepared using a one-step wet chemical method. The photocatalytic Rhodamine B degradation property and the photoelectrochemical performance of the graphene-ZnO quasi-shell-core composite are dependent on the amount of graphene oxide that is added. When the amount of graphene oxide added is 10 mg, the graphene-ZnO quasi-shell-core composite possesses the optimal photocatalytic degradation efficiency and the best photoelectrochemical performance. An efficient interfacial electric field is established on the interface between the graphene and ZnO, which significantly improves the separation efficiency of the photogenerated electron-hole pairs and thus dramatically increases its photoelectrochemical performance. In addition to the excellent photocatalytic and photoelectrochemical properties, the electron migration ability of the grephene-ZnO quasi-shell-core composite is significantly enhanced due to the graphene coating on ZnO surface; therefore, this material has great potential for application as a substrate material to accept electrons in dye solar cell and in narrow bandgap semiconductor quantum dot sensitized solar cells.




    Full Text Available The article presents the results of study the shell for energy-efficient environmental low-rise residential building, corresponding to the criteria of sustainable development in construction. Purpose. The purpose of the presented research is providing a study of parameters for shell of energy-efficient environmental low-rise buildings. Methodology. Research is carried out on the basis of an improved method for calculating the thermal characteristics of the external walling, as well as physical heat transfer simulation. Conclusion.The ratio between the thickness of external walling and the proportion of heat loss through them was determined, and also the heat loss through thermal "bridges" was studied. Originality. The limits for the optimum thickness of the external walling of ecological materials was analyzed, and it was offered solution for minimization of heat loss through the nodes of shell. Practical value.Recommendations are worked out on constructing of thermal shell at planning of energy-efficient low-rise residential buildings.

  1. An efficient finite element with layerwise mechanics for smart piezoelectric composite and sandwich shallow shells

    Yasin, M. Yaqoob; Kapuria, S.


    In this work, we present a new efficient four-node finite element for shallow multilayered piezoelectric shells, considering layerwise mechanics and electromechanical coupling. The laminate mechanics is based on the zigzag theory that has only seven kinematic degrees of freedom per node. The normal deformation of the piezoelectric layers under the electric field is accounted for without introducing any additional deflection variables. A consistent quadratic variation of the electric potential across the piezoelectric layers with the provision of satisfying the equipotential condition of electroded surfaces is adopted. The performance of the new element is demonstrated for the static response under mechanical and electric potential loads, and for free vibration response of smart shells under different boundary conditions. The predictions are found to be very close to the three dimensional piezoelasticity solutions for hybrid shells made of not only single-material composite substrates, but also sandwich substrates with a soft core for which the equivalent single layer (ESL) theories perform very badly.

  2. An efficient hybrid / mixed element for geometrically nonlinear analysis of plate and shell structures

    Duan, M.


    In this paper, a geometrically nonlinear hybrid/mixed curved quadrilateral shell element (HMSHEL4N) with four nodes is developed based on the modified Hellinger/Reissner variational principles. The performance of element is investigated and tested using some benchmark problems. A number of numerical examples of plate and shell nonlinear deflection problems are included. The results are compared with theoretical solutions and other numerical results. It is shown that HMSHEL4N does not possess spurious zero energy modes and any locking phenomenon, and is convergent and insensitive to the distorted mesh. A good agreement of the results with theoretical solutions, and better performance compared with displacement finite element method, are observed. It is seen that an efficient shell element based on stress and displacement field assumptions in solution and time is obtained.

  3. Metal oxide core shell nanostructures as building blocks for efficient light emission (SISGR)

    Chang, Jane P [Univ. of California, Los Angeles, CA (United States); Dorman, James [Univ. of California, Los Angeles, CA (United States); Cheung, Cyrus [Univ. of California, Los Angeles, CA (United States)


    The objective of this research is to synthesize core-shell nano-structured metal oxide materials and investigate their structural, electronic and optical properties to understand the microscopic pathways governing the energy conversion process, thereby controlling and improving their efficiency. Specifically, the goal is to use a single metal oxide core-shell nanostructure and a single excitation source to generate photons with long emission lifetime over the entire visible spectrum and when controlled at the right ratio, generating white light. In order to achieve this goal, we need to control the energy transfer between light emitting elements, which dictates the control of their interatomic spacing and spatial distribution. We developed an economical wet chemical process to form the nanostructured core and to control the thickness and composition of the shell layers. With the help from using DOE funded synchrotron radiation facility, we delineated the growth mechanism of the nano-structured core and the shell layers, thereby enhancing our understanding of structure-property relation in these materials. Using the upconversion luminescence and the lifetime measurements as effective feedback to materials sysnthes is and integration, we demonstrated improved luminescence lifetimes of the core-shell nano-structures and quantified the optimal core-multi-shell structure with optimum shell thickness and composition. We developed a rare-earths co-doped LaPO4 core-multishell structure in order to produce a single white light source. It was decided that the mutli-shell method would produce the largest increase in luminescence efficiency while limiting any energy transfer that may occur between the dopant ions. All samples resulted in emission spectra within the accepted range of white light generation based on the converted CIE color coordinates. The white light obtained varied between warm and cool white depending on the layering architecture, allowing for the

  4. New Active Organic Substance in Oyster Shell Capable of Scavenging Oxygen Free Radicals with High Efficiency

    MA Jian-hua


    A light purple organic active substance capable of scavenging hydroxyl radical·OH with a high efficiency was extracted from Oyster shell at an extraction rate of 2.49%.It was found for the first time that this active substance may scavenge ·OH with the efficiency far higher than that of vitamin C.This active substance may scavenge also superoxide radical(O2-·)although the scavenging efficiency is far lower than that of vitamin C.Infrared spectrometry and routine chemical analysis primarily reveal that this active substance belongs to glycoprotein.

  5. Decomposition approach to model smart suspension struts

    Song, Xubin


    Model and simulation study is the starting point for engineering design and development, especially for developing vehicle control systems. This paper presents a methodology to build models for application of smart struts for vehicle suspension control development. The modeling approach is based on decomposition of the testing data. Per the strut functions, the data is dissected according to both control and physical variables. Then the data sets are characterized to represent different aspects of the strut working behaviors. Next different mathematical equations can be built and optimized to best fit the corresponding data sets, respectively. In this way, the model optimization can be facilitated in comparison to a traditional approach to find out a global optimum set of model parameters for a complicated nonlinear model from a series of testing data. Finally, two struts are introduced as examples for this modeling study: magneto-rheological (MR) dampers and compressible fluid (CF) based struts. The model validation shows that this methodology can truly capture macro-behaviors of these struts.

  6. The Adsorption Efficiency of Chemically Prepared Activated Carbon from Cola Nut Shells by on Methylene Blue

    Julius Ndi Nsami; Joseph Ketcha Mbadcam


    The adsorption of methylene blue from aqueous solution onto activated carbon prepared from cola nut shell has been investigated under batch mode. The influence of major parameters governing the efficiency of the process such as, solution pH, sorbent dose, initial concentration, and contact time on the removal process was investigated. The time-dependent experimental studies showed that the adsorption quantity of methylene blue increases with initial concentration and decreasing adsorbent dosa...

  7. Efficient synthetic access to thermo-responsive core/shell nanoparticles

    Dine, Enaam Jamal Al; Ferjaoui, Zied; Roques-Carmes, Thibault; Schjen, Aleksandra; Meftah, Abdelaziz; Hamieh, Tayssir; Toufaily, Joumana; Schneider, Raphaël; Gaffet, Eric; Alem, Halima


    Core/shell nanostructures based on silica, fluorescent ZnO quantum dots (QDs) and superparamagnetic Fe3O4 nanoparticles (NPs) were prepared and fully characterized by the combination of different techniques and the physical properties of the nanostructures were studied. We demonstrate the efficiency of the atom transfer radical polymerization with activators regenerated by electron transfer process to graft (co-)polymers of different structures and polarity at the surface of metal oxide NPs. The influence of the polymer chain configuration on the optical properties of the ZnO/polymer core/shell QDs was enlightened. Concerning the magnetic properties of the Fe3O4/polymer nanostructures, only the amount of the grafted polymer plays a role on the saturation magnetization of the NPs and no influence of the aggregation was evidenced. The simple and fast process described in this work is efficient for the grafting of copolymers from surfaces and the derived NPs display the combination of the physical properties of the core and the macromolecular behavior of the shell.

  8. A New Estimation of Mass Accumulation Efficiency in Helium Shell Flashes toward Type Ia Supernova Explosions

    Kato, M


    We have calculated the mass accumulation efficiency during helium shell flashes to examine whether or not a carbon-oxygen white dwarf (C+O WD) grows up to the Chandrasekhar mass limit to ignite a Type Ia supernova explosion. It has been frequently argued that luminous super-soft X-ray sources and symbiotic stars are progenitors of SNe Ia. In such systems, a C+O WD accretes hydrogen-rich matter from a companion and burns hydrogen steadily on its surface. The WD develops a helium layer underneath the hydrogen-rich envelope and undergoes periodic helium shell flashes. Using OPAL opacity, we have reanalyzed a full cycle of helium shell flashes on a 1.3 M_ødot C+O WD and confirmed that the helium envelope of the WD expands to blow a strong wind. A part of the accumulated matter is lost by the wind. The mass accumulation efficiency is estimated as \\eta_{He} = -0.175 (\\log accretion rate \\dot M is in units of M_ødot yr^{-1}. In relatively high mass accretion rates as expected in recent SN Ia progenitor models, the...

  9. Variable volume combustor with aerodynamic support struts

    Ostebee, Heath Michael; Johnson, Thomas Edward; Stewart, Jason Thurman; Keener, Christopher Paul


    The present application provides a combustor for use with a gas turbine engine. The combustor may include a number of micro-mixer fuel nozzles and a fuel injection system for providing a flow of fuel to the micro-mixer fuel nozzles. The fuel injection system may include a number of support struts supporting the fuel nozzles and providing the flow of fuel therethrough. The support struts may include an aerodynamic contoured shape so as to distribute evenly a flow of air to the micro-mixer fuel nozzles.

  10. Solution-processed core-shell nanowires for efficient photovoltaic cells.

    Tang, Jinyao; Huo, Ziyang; Brittman, Sarah; Gao, Hanwei; Yang, Peidong


    Semiconductor nanowires are promising for photovoltaic applications, but, so far, nanowire-based solar cells have had lower efficiencies than planar cells made from the same materials, even allowing for the generally lower light absorption of nanowires. It is not clear, therefore, if the benefits of the nanowire structure, including better charge collection and transport and the possibility of enhanced absorption through light trapping, can outweigh the reductions in performance caused by recombination at the surface of the nanowires and at p-n junctions. Here, we fabricate core-shell nanowire solar cells with open-circuit voltage and fill factor values superior to those reported for equivalent planar cells, and an energy conversion efficiency of ∼5.4%, which is comparable to that of equivalent planar cells despite low light absorption levels. The device is made using a low-temperature solution-based cation exchange reaction that creates a heteroepitaxial junction between a single-crystalline CdS core and single-crystalline Cu2S shell. We integrate multiple cells on single nanowires in both series and parallel configurations for high output voltages and currents, respectively. The ability to produce efficient nanowire-based solar cells with a solution-based process and Earth-abundant elements could significantly reduce fabrication costs relative to existing high-temperature bulk material approaches.

  11. Influence of SiO2 shell thickness on power conversion efficiency in plasmonic polymer solar cells with Au nanorod@SiO2 core-shell structures

    Zhang, Ran; Zhou, Yongfang; Peng, Ling; Li, Xue; Chen, Shufen; Feng, Xiaomiao; Guan, Yuqiao; Huang, Wei


    Locating core-shell metal nanoparticles into a photoactive layer or at the interface of photoactive layer/hole extraction layer is beneficial for fully employing surface plasmon energy, thus enhancing power conversion efficiency (PCE) in plasmonic organic photovoltaic devices (OPVs). Herein, we first investigated the influence of silica shell thickness in Au nanorods (NRs)@SiO2 core-shell structures on OPV performances by inserting them into poly(3,4-ethylenedioxythiophene):poly(4-styrenesulfonate) and thieno[3,4-b]thiophene/benzodithiophene (PTB7) interface, and amazedly found that a 2–3 nm silica shell onto Au NRs induces a highest short-circuit current density of 21.2 mA cm‑2 and PCE of 9.55%. This is primarily due to an extremely strong local field and a much slower attenuation of localized surface plasmon resonance around ultrathin silica-coated Au NRs, with which the field intensity remains a high value in the active layer, thus sufficiently improves the absorption of PTB7. Our work provides a clear design concept on precise control of the shell of metal nanoparticles to realize high performances in plasmonic OPVs.

  12. Template-Engaged Solid-State Synthesis of Barium Magnesium Silicate Yolk@Shell Particles and Their High Photoluminescence Efficiency.

    Chen, Xuncai; Kim, Woo-Sik


    This study presents a new synthetic method for fabricating yolk@shell-structured barium magnesium silicate (BMS) particles through a template-engaged solid-state reaction. First, as the core template, (BaMg)CO3 spherical particles were prepared based on the coprecipitation of Ba(2+) and Mg(2+) . These core particles were then uniformly shelled with silica (SiO2 ) by using CTAB as the structure-directing template to form (BaMg)CO3 @SiO2 particles with a core@shell structure. The (BaMg)CO3 @SiO2 particles were then converted to yolk@shell barium magnesium silicate (BMS) particles by an interfacial solid-state reaction between the (BaMg)CO3 (core) and the SiO2 (shell) at 750 °C. During this interfacial solid-state reaction, Kirkendall diffusion contributed to the formation of yolk@shell BMS particles. Thus, the synthetic temperature for the (BaMg)SiO4 :Eu(3+) phosphor is significantly reduced from 1200 °C with the conventional method to 750 °C with the proposed method. In addition, the photoluminescence intensity of the yolk@shell (BaMg)SiO4 :Eu(3+) phosphor was found to be 9.8 times higher than that of the conventional (BaMg)SiO4 :Eu(3+) phosphor. The higher absorption of excitation light by the structure of the yolk@shell phosphor is induced by multiple light-reflection and -scattering events in the interstitial void between the yolk and the shell. When preparing the yolk@shell (BaMg)SiO4 :Eu(3+) phosphor, a hydrogen environment for the solid-state reaction results in higher photoluminescence efficiency than nitrogen and air environments. The proposed synthetic method can be easily extended to the synthesis of other yolk@shell multicomponent metal silicates.

  13. Force-State Characterization of Struts Using Pinned Joints

    Brook D. Ferney


    Full Text Available As part of a research effort to study the microgravity dynamics of a truss with pinned joints, a single strut with a single clevis-tang pinned joint was characterized. Experimental data was collected using a force-state mapping technique. The strut was subjected to axial dynamic loads and the response of the strut was measured. The force-state map aids visualization of the strut dynamics. Finite element modeling of the response was explored. An example is presented that uses a method of manual determination of the finite element model parameters. The finite element model results correspond well with the measured strut response.

  14. Application of the OA system based on Struts + Spring + Hibernate%Struts+Spring+Hibernate在OA系统开发中的应用

    卢凯霞; 程耕国


    介绍了Struts,Hibernate和Spring三个开源框架及它们对MVC设计模式的实现,通过分析各个开源架构关键技术的基本特征,阐述了如何更好地将三者整合起来构建一个结构清晰、低藕合度、易于扩展的J2EE分层架构.最后给出了该架构在OA系统开发中的应用实例,在实践中体现出MVC设计模式与Struts+ Spring+ Hibernate架构的高效和结构清晰的优点,同时也为开发管理信息系统提供了理论指导.%This paper introduces the Struts,Hibermate and Spring,three open sources of MVC framework and their realization of design patterns. By analyzing the basic characteristics of key technologies of the various open-source framework, it expounds how to integrate the three structures to construct a clear, low degree of lotus, easy to expand J2EE layered structure. Finally it gives application examples of the structure in OA system development. In practice the advantages of efficiency and clarity in MVC design patterns and Struts + Spring + Hibernate architecture are realized. And also for the development of management information system it provides theoretical guidance.

  15. High quality ZnO–TiO{sub 2} core–shell nanowires for efficient ultraviolet sensing

    Shao, Dali, E-mail: [Department of Electrical, Computer and Systems Engineering, Rensselaer Polytechnic Institute, Troy, NY 12180 (United States); Sun, Hongtao; Xin, Guoqing; Lian, Jie [Department of Mechanical, Aerospace and Nuclear Engineering, Rensselaer Polytechnic Institute, Troy, NY 12180 (United States); Sawyer, Shayla [Department of Electrical, Computer and Systems Engineering, Rensselaer Polytechnic Institute, Troy, NY 12180 (United States)


    Graphical abstract: - Highlights: • High quality ZnO–TiO{sub 2} core–shell nanowires were grown using hydrothermal process followed by atomic layer deposition method. • The ZnO–TiO{sub 2} core–shell nanowires demonstrated high photoresponsivity (495 A/W at 373 nm). • High photocurrent to dark current ratio (2.3 × 10{sup 4}) has been achieved. - Abstract: High quality ZnO–TiO{sub 2} core–shell nanowires (NWs) have been fabricated via a facile two-step method: growth of ZnO nanowires by hydrothermal synthesis and then coating of highly uniform TiO{sub 2} shell using atomic layer deposition (ALD) technique. The ultraviolet (UV) emission intensity of the ZnO–TiO{sub 2} core–shell NWs is largely quenched due to an efficient electron–hole separation that reduces the band-to-band recombinations. To the contrary, the absorption of the ZnO–TiO{sub 2} core–shell NWs in both UV and visible region is enhanced, which is attributed to the antireflection properties of the TiO{sub 2} shell. An UV photodetector fabricated from the ZnO–TiO{sub 2} core–shell NWs showed a maximum photoresponsivity as high as 495 A/W at 373 nm under −10 V, which is ∼8 times higher than that of the photodetector fabricated from bare ZnO NWs. In addition, the transient response of the ZnO–TiO{sub 2} core–shell NWs is improved by 6 times as compared to that of the bare ZnO NWs. The results presented in this work suggest that ZnO–TiO{sub 2} core–shell NWs may be promising for various optoelectronics applications including: UV photodetectors, optical switches, optical fibers and solar cells.

  16. Double-Shelled Nanocages with Cobalt Hydroxide Inner Shell and Layered Double Hydroxides Outer Shell as High-Efficiency Polysulfide Mediator for Lithium-Sulfur Batteries.

    Zhang, Jintao; Hu, Han; Li, Zhen; Lou, Xiong Wen David


    Lithium-sulfur (Li-S) batteries have been considered as a promising candidate for next-generation electrochemical energy-storage technologies because of their overwhelming advantages in energy density. Suppression of the polysulfide dissolution while maintaining a high sulfur utilization is the main challenge for Li-S batteries. Here, we have designed and synthesized double-shelled nanocages with two shells of cobalt hydroxide and layered double hydroxides (CH@LDH) as a conceptually new sulfur host for Li-S batteries. Specifically, the hollow CH@LDH polyhedra with complex shell structures not only maximize the advantages of hollow nanostructures for encapsulating a high content of sulfur (75 wt %), but also provide sufficient self-functionalized surfaces for chemically bonding with polysulfides to suppress their outward dissolution. When evaluated as cathode material for Li-S batteries, the CH@LDH/S composite shows a significantly improved electrochemical performance.

  17. Compositional arrangement of rod/shell nanoparticles: an approach to provide efficient plasmon waveguides

    Ahmadivand, A.; Golmohammadi, S.


    In this work, we investigated the optical properties of a novel compositional configuration of gold nanorod and silver nanoshell which is embedded in a SiO2 substance. The proper geometrical sizes for compositional rod/shell arrangement have been obtained based on the position and peak of plasmon resonance at λ ˜1550 nm. Adjusting the plasmon resonance position at declared spectrum helps us to provide an arrangement which shows high efficiency and minimum losses. The influence of destructive components such as internal damping and scattering on the rod/shell combination is demonstrated by corresponding diagrams. Moreover, we proposed a nano-array based on examined configuration and the quality of light transmission along the array is studied. We figured out and depicted optical properties of the array such as transmission loss factors, group velocities, transmitted power, transmission quality, and two-dimensional snapshots of surface plasmons (SPs) coupling between nanoparticles arrangements under transverse and longitudinal modes excitations. Ultimately, it is shown that the suggested nanostructure based on studied nanoparticles configuration has a potential to utilize in designing nanophotonic devices such as splitters, couplers, and routers. Finite-difference time-domain method (FDTD) as a major simulation model has been employed to study the features of the waveguide.

  18. Core-shell gold J-aggregate nanoparticles for highly efficient strong coupling applications

    Djoumessi Lekeufack, Diane; Brioude, Arnaud; Coleman, Anthony W.; Miele, Philippe; Bellessa, Joel; De Zeng, Li; Stadelmann, Pierre


    We have developed a straightforward synthetic route to prepare core-shell systems based on gold nanoparticles (NPs) surrounded with J-aggregates molecules. This synthesis allows the direct and efficient coating, at room temperature, of pretreated citrate-stabilized gold NPs with 5, 5', 6, 6'-tetrachloro-1-1'-diethyl-3, 3'-di (4-sulfobutyl)-benzimidazolocarbocyanine (TDBC), without supplementary adding of salts and bases during the synthesis. As the size of gold particle is tunable, the precise optimization of the strong coupling between the electronic transitions of organic components (TDBC) and the plasmon modes of the gold NPs is achieved corresponding to a Rabi energy of 220 meV, a value not yet obtained in such a system.

  19. Production Efficiency of Cocoon Shell of Silkworm, Bombyx mori L. (Bombycidae: Lepidoptera, as an Index for Evaluating the Nutritive Value of Mulberry, Morus sp. (Moraceae, Varieties

    Jalaja Suresh Kumar


    Full Text Available The nutritional efficiency of mulberry leaves consumed by silkworms, Bombyx mori L., is usually evaluated in terms of the proportion of cocoon shell weight to the amount of food ingested. The production efficiency of cocoon shell is generally used to identify the superiority of a mulberry variety for silkworm rearing. In this study the production efficiency of cocoon shell was used as an index for evaluating the nutritive value of different mulberry varieties of India. Among the varieties, V-1, having highest production efficiency of cocoon shell with less amount of food ingested and highest digestibility, is regarded as the best suitable variety with nutritive values ideal for silkworm rearing.

  20. An Algorithm for Constructing 3D Struts

    George W. Hart


    A simple robust "strut algorithm" is presented which, when given a graph embedded in 3D space, thickens its edges into solid struts. Various applications, crystallographic and sculptural, are shown in which smooth high-genus forms are the output. A toolbox of algorithmic techniques allow for a variety of novel, visually engaging forms that express a mathematical aesthetic. In sculptural examples, hyperbolic tessellations in the Poincare plane are transformed in several ways to three-dimensional networks of edges embodied within a plausibly organic organization. By the use of different transformations and adjustable parameters in the algorithms, a variety of attractive forms result. The techniques produce watertight boundary representations that can be built with solid freeform fabrication equipment. The final physical output satisfies the "coolness criterion," that passers by will pick them up and say "Wow, that's cool!"

  1. A Preliminary Investigation of Wastewater Treatment Efficiency and Economic Cost of Subsurface Flow Oyster-Shell-Bedded Constructed Wetland Systems

    Chia-Chuan Hsu


    Full Text Available We conducted a preliminary investigation of wastewater treatment efficiency and economic cost of the oyster-shell-bedded constructed wetlands (CWs compared to the conventional gravel-bedded CW based on field monitoring data of water quality and numerical modeling. Four study subsurface (SSF CWs were built to receive wastewater from Taipei, Taiwan. Among these sites, two are vertical wetlands, filled with bagged- (VA and scattered- (VB oyster shells, and the other two horizontal wetlands were filled with scattered-oyster shells (HA and gravels (HB. The BOD, NO3−, DO and SS treatment efficiency of VA and VB were higher than HA and HB. However, VA was determined as the best option of CW design due to its highest cost-effectiveness in term of BOD removal (only 6.56 US$/kg as compared to VB, HA and HB (10.88–25.01 US$/kg. The results confirmed that oyster shells were an effective adsorption medium in CWs. Hydraulic design and arrangement of oyster shells could be important in determining their treatment efficiency and cost-effectiveness. A dynamic model was developed to simulate substance transmissions in different treatment processes in the CWS using AQUASIM 2.1 based on the water quality data. Feasible ranges of biomedical parameters involved were determined for characterizing the importance of different biochemical treatment processes in SSF CWs. Future work will involve extending the experimental period to confirm the treatment efficiency of the oyster-shell-bedded CW systems in long-term operation and provide more field data for the simulated model instead of the literature values.

  2. Soft Proton Scattering Efficiency Measurements on X-Ray Mirror Shells

    Diebold, S; Perinati, E; Santangelo, A; Freyberg, M; Friedrich, P; Jochum, J


    In-orbit experience has shown that soft protons are funneled more efficiently through focusing Wolter-type optics of X-ray observatories than simulations predicted. These protons can degrade the performance of solid-state X-ray detectors and contribute to the instrumental background. Since laboratory measurements of the scattering process are rare, an experiment for grazing angles has been set up at the accelerator facility of the University of T\\"ubingen. Systematic measurements at incidence angles ranging from 0.3{\\deg} to 1.2{\\deg} with proton energies around 250 keV, 500 keV, and 1 MeV have been carried out. Parts of spare mirror shells of the eROSITA (extended ROentgen Survey with an Imaging Telescope Array) instrument have been used as scattering targets. This publication comprises a detailed description of the setup, the calibration and normalization methods, and the scattering efficiency and energy loss results. A comparison of the results with a theoretical scattering description and with simulations...

  3. Redefining the Septal L-Strut to Prevent Collapse

    Ha, Dong-Heon; Kim, Sung Won; Cho, Dong-Woo


    During septorhinoplasty, septal cartilage is frequently resected for various purposes but the L-strut is preserved. Numerous materials are inserted into the nasal dorsum during dorsal augmenation rhinoplasty without considering nasal structural safety. This study used a finite element method (FEM) to redefine the septal L-strut, to prevent collapse as pressure moved from the rhinion to the supratip breakpoint on the nasal dorsum and as the contact percentage between the caudal L-strut and the maxillary crest changed. We designed a 1-cm-wide L-strut model based on computed tomography data. At least 45% of the width of the L-strut in the inferior portion of the caudal strut must be preserved during septoplasty to stabilize the septum. In augmentation rhinoplasty, the caudal L-strut must either be preserved perfectly or reinforced to prevent collapse or distortion of the L-strut. The dorsal augmentation material must be fixed in an augmentation pocket to prevent movement of graft material toward the supratip breakpoint, which can disrupt the L-strut. We conducted a numerical analysis using a FEM to predict tissue/organ behavior and to help clinicians understand the reasons for target tissue/organ collapse and deformation. PMID:27073993

  4. Sensitization enhancement of europium in ZnSe/ZnS core/shell quantum dots induced by efficient energy transfer.

    Liu, Ni; Xu, Ling; Wang, Hongyu; Xu, Jun; Su, Weining; Ma, Zhongyuan; Chen, Kunji


    Eu-doped ZnSe:/ZnS quantum dots (formed as ZnSe:Eu/ZnS QDs) were successfully synthesized by a two-step wet chemical method: nucleation doping and epitaxial shell growing. The sensitization characteristics of Eu-doped ZnSe and ZnSe/ZnS core/shell QD are studied in detail using photoluminescence (PL), PL excitation spectra (PLE) and time-resolved PL spectroscopy. The emission intensity of Eu ions is enhanced and that of ZnSe QDs is decreased, implying that energy was transferred from the excited ZnSe host materials (the donor) to the doped Eu ions (the acceptor). PLE reveals that the ZnSe QDs act as an antenna for the sensitization of Eu ions through an energy transfer process. The dynamics of ZnSe:Eu/ZnS core/shell quantum dots with different shell thicknesses and doping concentrations are studied via PL spectra and fluorescence lifetime spectra. The maximum phosphorescence efficiency is obtained when the doping concentration of Eu is approximately 6% and the sample showed strong white light under ultraviolet lamp illumination. By surface modification with ZnS shell layer, the intensity of Eu-related PL emission is increased approximately three times compared with that of pure ZnSe:Eu QDs. The emission intensity and wavelength of ZnSe:Eu/ZnS core/shell quantum dots can be modulated by different shell thickness and doping concentration. The results provide a valuable insight into the doping control for practical applications in laser, light-emitting diodes and in the field of biotechnology. Copyright © 2014 John Wiley & Sons, Ltd.

  5. 40% Efficiency enhancement in solar cells using ZnO nanorods as shell prepared via novel hydrothermal synthesis

    Ebadi, Mohammad; Zarghami, Zabihullah; Motevalli, Kourosh


    Herein, rod-like ZnO nanostructures were synthesized via a novel hydrothermal route using Zn(OAc)2, ethylenediamine and hydrazine as a new set of starting reagents. The as-synthesized products were characterized by techniques including XRD, EDS, SEM, XPS, Pl and FTIR. The prepared ZnO nanostructures were utilized as shell on TiO2 film in DSSCs. Effect of precursor type, morphology and thickness of ZnO shell (number of electrophoresis cycle) on solar cells efficiency were well studied. Our results showed that ethylenediamine has crucial effect on morphology of synthesized ZnO nanostructures and using ZnO nanostructures leads to an increase in DSSCs efficiency compared to bare TiO2 from 4.66 to 7.13% ( 40% improvement). Moreover, highest amount of solar cell efficiency (7.13%) was obtained by using ZnO nanorods with two cycle of electrophoresis for deposition.

  6. 基于Struts2和Ajax的企业级Web应用开发%Development of enterprise Web application based on Struts2 and Ajax

    甘文丽; 刘为超


    In view of problems of low data transmission efficiency and response speed and bad user experience between client and server in traditional development of enterprise Web application, the paper proposed a development scheme of enterprise Web application based on Struts2 + jQuery Ajax, and the scheme was applied to development of small and medium-scaled coal enterprise customer relationship management system. It introduced whole framework and implementation of main function modules of the system in details. The actual application showed that the scheme of Struts2+jQuery Ajax can effectively improve development efficiency and maintainability and scalability of customer relationship management system, and greatly improves response speed of Web application program and effect of user experience.%针对传统的企业级Web应用开发中客户端与服务器端之间存在数据传输效率和响应速度低、用户体验差的问题,提出了一种基于Struts2 +jQuery Ajax的企业级Web应用开发方案,并将该方案运用到中小型煤炭企业客户关系管理系统的开发中;详细介绍了该系统的整体架构及主要功能模块的实现.实际应用表明,Struts2 +jQuery Ajax这种方案可以有效提高客户关系管理系统的开发效率及其可维护性和可扩展性,并且极大提升了Web应用程序的响应速度及用户体验效果.

  7. The Adsorption Efficiency of Chemically Prepared Activated Carbon from Cola Nut Shells by on Methylene Blue

    Julius Ndi Nsami


    Full Text Available The adsorption of methylene blue from aqueous solution onto activated carbon prepared from cola nut shell has been investigated under batch mode. The influence of major parameters governing the efficiency of the process such as, solution pH, sorbent dose, initial concentration, and contact time on the removal process was investigated. The time-dependent experimental studies showed that the adsorption quantity of methylene blue increases with initial concentration and decreasing adsorbent dosage. The equilibrium time of 180 min was observed and maximum adsorption was favoured at pH 3.5. The dye removal using 0.1 g of adsorbent was more than 90%. This dosage (0.1 g was considered as the optimum dosage to remove methylene blue from aqueous solutions. The equilibrium adsorption data were analyzed by the Freundlich, Langmuir adsorption isotherm models. The kinetics of methylene blue solution was discussed by pseudo-first-order, pseudo-second-order, and Elovich models. The adsorption process follows the Elovich rate kinetic model, having a correlation coefficient in the range between 0.9811 and 1.

  8. High-efficient production of SiC/SiO2 core-shell nanowires for effective microwave absorption

    Zhong, Bo


    In the current report, we have demonstrated that the high-efficient production of SiC/SiO2 core-shell nanowires can be achieved through the introduction of trace of water vapor during the chemical vapor deposition process. The yield of the SiC/SiO2 core-shell nanowires is dramatically improved due to the introduction of water vapor. The SiC/SiO2 core-shell nanowires exhibit an excellent microwave absorption property in the frequency range of 2.0–18.0GHz with a very low weight percentage of 0.50wt.% in the absorbers. A minimum reflection loss value of −32.72dB (>99.99% attenuation) at 13.84GHz has been observed with the absorber thickness of 3.0mm. Moreover, the SiC/SiO2 core-shell nanowires based absorber can reach an effective absorption bandwidth (<−10dB) of 5.32GHz with the absorber thickness of 3.5mm. Furthermore, a possible absorption mechanism is also proposed in detail for such effective attenuation of microwave which can be attributed to the dielectric loss and magnetic loss of SiC/SiO2 core-shell nanowires.

  9. A Catenated Strut in a Catenated Metal–Organic Framework

    Li, Qiaowei; Sue, C.-H.; Basu, S.; Shveyd, A. K.; Zhang, Wenyu; Barin, G.; Fang, Lei; Sarjeant, A. A.; Stoddart, J. F.; Yaghi, Omar M


    Mechanically interlocked molecules (MIMs), in the form of donor–acceptor [2]catenane-containing struts of exceptional length, have been incorporated into a three-dimensional catenated metal–organic framework (MOF) at precise locations and with uniform relative orientations. Catenation is expressed simultaneously within the struts and the framework.

  10. Reversible Interactions of Proteins with Mixed Shell Polymeric Micelles: Tuning the Surface Hydrophobic/Hydrophilic Balance toward Efficient Artificial Chaperones.

    Wang, Jianzu; Song, Yiqing; Sun, Pingchuan; An, Yingli; Zhang, Zhenkun; Shi, Linqi


    Molecular chaperones can elegantly fine-tune its hydrophobic/hydrophilic balance to assist a broad spectrum of nascent polypeptide chains to fold properly. Such precious property is difficult to be achieved by chaperone mimicking materials due to limited control of their surface characteristics that dictate interactions with unfolded protein intermediates. Mixed shell polymeric micelles (MSPMs), which consist of two kinds of dissimilar polymeric chains in the micellar shell, offer a convenient way to fine-tune surface properties of polymeric nanoparticles. In the current work, we have fabricated ca. 30 kinds of MSPMs with finely tunable hydrophilic/hydrophobic surface properties. We investigated the respective roles of thermosensitive and hydrophilic polymeric chains in the thermodenaturation protection of proteins down to the molecular structure. Although the three kinds of thermosensitive polymers investigated herein can form collapsed hydrophobic domains on the micellar surface, we found distinct capability to capture and release unfolded protein intermediates, due to their respective affinity for proteins. Meanwhile, in terms of the hydrophilic polymeric chains in the micellar shell, poly(ethylene glycol) (PEG) excels in assisting unfolded protein intermediates to refold properly via interacting with the refolding intermediates, resulting in enhanced chaperone efficiency. However, another hydrophilic polymer-poly(2-methacryloyloxyethyl phosphorylcholine) (PMPC) severely deteriorates the chaperone efficiency of MSPMs, due to its protein-resistant properties. Judicious combination of thermosensitive and hydrophilic chains in the micellar shell lead to MSPM-based artificial chaperones with optimal efficacy.

  11. Experimental investigation of unsteady fan flow interaction with downstream struts

    Ng, W. F.; Obrien, W. F.; Olsen, T. L.


    In the present study of the unsteady pressure field produced on fan rotor blades by interaction with downstream struts, a single stage, low speed axial-flow fan was instrumented with blade-mounted high frequency pressure transducers. In addition, stationary pressure problems were used to map out the flowfield. Fluctuating pressure measurements are presented for blade midspan and 85-percent span on both the suction and pressure surfaces of the rotor blades at several positions of the downstream struts, and for two different flow coefficients. The strut is found to produce an effect on the unsteady pressure field on the rotor blades; this effect exceeds that due to the stator at design rotor-stator-strut spacing, but it rapidly declines as the struts are moved downstream.

  12. Flow field characteristics analysis and combustion modes classification for a strut/cavity dual-mode combustor

    Zhang, Chenlin; Chang, Juntao; Zhang, Yuanshi; Wang, Youyin; Bao, Wen


    Experimental and numerical study of a strut/cavity dual-mode combustor has been conducted in this paper. Under different fuel equivalence ratio and allocation proportion conditions, the pressure distribution and flow field structure of combustor show distinct characteristics. For strut fuel injecting at a low equivalence ratio, the luminosity images show that combustion zone distributes in the shear layer behind the strut. The wall fuel injecting before strut would change the starting point of pressure rising. Based on the flow field structure, the dual-mode combustor operation process is classified into three combustion modes, including scramjet mode, weak ramjet mode and strong ramjet mode. Because of a strong interaction of the shock wave with the boundary layer, weak ramjet mode has a stronger isolator compression effect and higher combustion efficiency than scramjet mode. With heat release increasing, the thermal throat formation is an indication of the strong ramjet mode, which has a subsonic gap in the isolator. Further, by judging the pressure from dominant pressure sensor before the strut, the three different combustion modes could be classified. Comparing the specific impulse of combustor, it has an obvious distinction in the different combustion modes.

  13. Hybrid carbon nanoparticles modified core-shell silica: a high efficiency carbon-based phase for hydrophilic interaction liquid chromatography.

    Ibrahim, Mohammed E A; Wahab, M Farooq; Lucy, Charles A


    Hydrophilic interaction liquid chromatography (HILIC) is a fast growing separation technique for hydrophilic and polar analytes. In this work, we combine the unique selectivity of carbon surfaces with the high efficiency of core-shell silica. First, 5 μm core-shell silica is electrostatically coated with 105 nm cationic latex bearing quaternary ammonium groups. Then 50 nm anionic carbon nanoparticles are anchored onto the surface of the latex coated core-shell silica particles to produce a hybrid carbon-silica phase. The hybrid phase shows different selectivity than ten previously classified HILIC column chemistries and 36 stationary phases. The hybrid HILIC phase has shape selectivity for positional isomeric pairs (phthalic/isophthalic and 1-naphthoic/2-naphthoic acids). Fast and high efficiency HILIC separations of biologically important carboxylates, phenols and pharmaceuticals are reported with efficiencies up to 85,000 plates m(-1). Reduced plate height of 1.9 (95,000 plates m(-1)) can be achieved. The hybrid phase is stable for at least 3 months of usage and storage under typical HILIC eluents.

  14. Au@Ag core-shell nanocubes for efficient plasmonic light scattering effect in low bandgap organic solar cells.

    Baek, Se-Woong; Park, Garam; Noh, Jonghyeon; Cho, Changsoon; Lee, Chun-Ho; Seo, Min-Kyo; Song, Hyunjoon; Lee, Jung-Yong


    In this report, we propose a metal-metal core-shell nanocube (NC) as an advanced plasmonic material for highly efficient organic solar cells (OSCs). We covered an Au core with a thin Ag shell as a scattering enhancer to build Au@Ag NCs, which showed stronger scattering efficiency than Au nanoparticles (AuNPs) throughout the visible range. Highly efficient plasmonic organic solar cells were fabricated by embedding Au@Ag NCs into an anodic buffer layer, poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS), and the power conversion efficiency was enhanced to 6.3% from 5.3% in poly[N-9-hepta-decanyl-2,7-carbazole-alt-5,5-(4,7-di-2-thienyl-2,1,3-benzothiadiazole)] (PCDTBT):[6,6]-phenyl C71-butyric acid methyl ester (PC70BM) based OSCs and 9.2% from 7.9% in polythieno[3,4-b]thiophene/benzodithiophene (PTB7):PC70BM based OSCs. The Au@Ag NC plasmonic PCDTBT:PC70BM-based organic solar cells showed 2.2-fold higher external quantum efficiency enhancement compared to AuNPs devices at a wavelength of 450-700 nm due to the amplified plasmonic scattering effect. Finally, we proved the strongly enhanced plasmonic scattering efficiency of Au@Ag NCs embedded in organic solar cells via theoretical calculations and detailed optical measurements.

  15. Facile synthesis of yolk-shell magnetic mesoporous carbon microspheres for efficient enrichment of low abundance peptides

    Wan, Hao; Qin, Hongqiang; Xiong, Zhichao; Zhang, Weibing; Zou, Hanfa


    Magnetic mesoporous carbon microspheres with a yolk-shell structure (YSMMCS) have been prepared via a new in situ carbon source strategy. The material was fabricated by two shells coated onto the Fe3O4 particles; the inner dense and thick silica shell could protect the magnetic core from harsh acidic solvents as well as induce the void between the core and the outer shell for the yolk-shell structure, while the outer organosilica shell was used as the template and carbon source for in situ preparation of a carbon shell with mesoporous structure. A C18-alkyl chain was incorporated in situ as the carbon precursor efficiently, avoiding the conventional infiltration step, which was very difficult to manipulate and time-consuming with the possibility of losing the carbon precursor. The resulting yolk-shell magnetic mesoporous carbon microspheres exhibited a high surface area (273.15 m2 g-1), a large pore volume (0.31 cm3 g-1), and a strong magnetic response (a saturation magnetization value of 34.57 emu g-1). As a result of the void between the core and the outer shell and the π-π stacking effect, adsorption capacity reached 191.64 mg g-1 by using Rhodamine B as a standard analyte, indicating the great potential application of the material as drug carriers. Owing to the inherent hydrophobicity and high surface area, the composite material showed better performance in the enrichment of peptides than a magnetic mesoporous silica material (Fe2O3@nSiO2@mSiO2). According to the LC-MS/MS results, about 51 and 29 nonredundant peptides were identified from tryptic digests of 5 nM BSA. Additionally, taking advantage of the mesoporous structure and strong magnetic response, the material was utilized to selectively extract low abundance endogenous peptides from human serum in the presence of high abundance proteins. Based on the LC-MS/MS results, 962 endogenous peptides were obtained by 2.5 mg YSMMCS relative to 539 endogenous peptides by 5 mg Fe2O3@nSiO2@mSiO2, confirming the

  16. Mass retention efficiency and i-process nucleosynthesis in He-shell flash evolution of rapidly accreting white dwarfs

    Denissenkov, Pavel; Battino, Umberto; Ritter, Christian; Pignatari, Marco; Jones, Samuel; Paxton, Bill


    Based on stellar evolution simulations, we demonstrate that rapidly accreting white dwarfs (RAWDs) in close binary systems, like those considered in the single-degenerate progenitor channel of type Ia supernovae, experience recurrent and very strong He-shell flashes in the stable H-burning accretion regime. The He-shell flashes result in the expansion and, utimately, ejection of the newly-accreted material via super-Eddington luminosity winds or Roche-lobe overflow. The white dwarf models do not retain any significant amount of the accreted mass, with a He retention efficiency of < 10% depending on mass and convective boundary mixing assumptions. This makes the evolutionary path of such systems to supernova Ia explosion highly unlikely. Instead, we have discovered that such binary systems are an astrophysical site for the intermediate neutron-capture process. In each of the He-shell flashes H-rich material enters the He-shell flash convection zone. 1D stellar evolution simulations of RAWDs show the H-inges...

  17. A Parametric Survey of Hydrofoil Strut Flutter


    Hydrodynamics - Subcavitating, Supercavitating, Ventilation 20 ABSTRACT (Cfmttnv* on ravaraa aide It n9C9»*mry mnd Identity by blaeb nufttoerj z^tt n...approximately 12 in. and lengths of 4 to 5 ft. The struts differed primarily in profile (blunt base, blunt leading edge, or streamlined) and in stiffness (a...CM VIH •H "V. u o u M 01 CM J VJ VH tfl u ■»>» a u *^, 4J y c >U 3 d 01 at 0) » T3 4J UH a MH IM o Ŕ to o a> 4J 0) * X O 4) c a c c •rl i o c 1

  18. Strut Deformation in CFRP-Strengthened Reinforced Concrete Deep Beams

    Mohammad Panjehpour


    Full Text Available Strut-and-tie model (STM method evolved as one of the most useful designs for shear critical structures and discontinuity regions (D-regions. It provides widespread applications in the design of deep beams as recommended by many codes. The estimation of bottle-shaped strut dimensions, as a main constituent of STM, is essential in design calculations. The application of carbon fibre reinforced polymer (CFRP as lightweight material with high tensile strength for strengthening D-regions is currently on the increase. However, the CFRP-strengthening of deep beam complicates the dimensions estimation of bottle-shaped strut. Therefore, this research aimed to investigate the effect of CFRP-strengthening on the deformation of RC strut in the design of deep beams. Two groups of specimens comprising six unstrengthened and six CFRP-strengthened RC deep beams with the shear span to the effective depth ratios (a/d of 0.75, 1.00, 1.25, 1.50, 1.75, and 2.00 were constructed in this research. These beams were tested under four-point bending configuration. The deformation of struts was experimentally evaluated using the values of strain along and perpendicular to the strut centreline. The evaluation was made by the comparisons between unstrengthened and CFRP-strengthened struts regarding the widening and shortening. The key variables were a/d ratio and applied load level.

  19. Impact damage in small diameter graphite/epoxy composite struts

    Chen, G.-S.; Bidinger, G. M.; Cho, S.; Lou, M. C.


    An investigation was performed to study impact induced damage in small-diameter struts made of a composite material with a brittle matrix system. The major focus is on characterizing the impact behavior associated with the barely visible damage. An experimental procedure including ultrasonic inspection, instrumented impact testing, and delamination buckling and residual strength measurements is presented. From the ultrasonic inspection, it is found that for the strut specimens under investigation, the impact energy level for barely visible damage threshold is above that of the internal damage threshold. A 60- to 65-percent reduction in compressive strength was typical for struts subjected to the barely visible impact damage threshold.

  20. Long range node-strut analysis of trabecular bone microarchitecture

    Schmah, Tanya; Marwan, Norbert; Thomsen, Jesper Skovhus


    of the trabecular bone network. METHODS: Similar in some ways to the topological node-strut analysis introduced by Garrahan et al. [J. Microsc. 142, 341-349 (1986)], our method is distinguished by an emphasis on long-range trabecular connectivity. Thus, while the topological classification of a pixel (after...... skeletonization) as a node, strut, or terminus, can be determined from the 3 × 3 neighborhood of that pixel, our method, which does not involve skeletonization, takes into account a much larger neighborhood. In addition, rather than giving a discrete classification of each pixel as a node, strut, or terminus, our...

  1. Efficient and accurate local single reference correlation methods for high-spin open-shell molecules using pair natural orbitals

    Hansen, Andreas; Liakos, Dimitrios G.; Neese, Frank


    A production level implementation of the high-spin open-shell (spin unrestricted) single reference coupled pair, quadratic configuration interaction and coupled cluster methods with up to doubly excited determinants in the framework of the local pair natural orbital (LPNO) concept is reported. This work is an extension of the closed-shell LPNO methods developed earlier [F. Neese, F. Wennmohs, and A. Hansen, J. Chem. Phys. 130, 114108 (2009), 10.1063/1.3086717; F. Neese, A. Hansen, and D. G. Liakos, J. Chem. Phys. 131, 064103 (2009), 10.1063/1.3173827]. The internal space is spanned by localized orbitals, while the external space for each electron pair is represented by a truncated PNO expansion. The laborious integral transformation associated with the large number of PNOs becomes feasible through the extensive use of density fitting (resolution of the identity (RI)) techniques. Technical complications arising for the open-shell case and the use of quasi-restricted orbitals for the construction of the reference determinant are discussed in detail. As in the closed-shell case, only three cutoff parameters control the average number of PNOs per electron pair, the size of the significant pair list, and the number of contributing auxiliary basis functions per PNO. The chosen threshold default values ensure robustness and the results of the parent canonical methods are reproduced to high accuracy. Comprehensive numerical tests on absolute and relative energies as well as timings consistently show that the outstanding performance of the LPNO methods carries over to the open-shell case with minor modifications. Finally, hyperfine couplings calculated with the variational LPNO-CEPA/1 method, for which a well-defined expectation value type density exists, indicate the great potential of the LPNO approach for the efficient calculation of molecular properties.

  2. Richtmyer-Meshkov Instability Induced Mixing Enhancement in the Scramjet Combustor with a Central Strut

    Qingchun Yang


    Full Text Available Experimental and numerical study of Richtmyer-Meshkov instability (RMI induced mixing enhancement has been conducted in a liquid-fueled scramjet engine with a central strut. To generate the RMI in the scramjet engine, transverse high temperature jets are employed downstream the strut injector. Compared to the transverse ordinary temperature jet, the jet penetration into the supersonic airstream of high temperature jet increases by 60%. The numerical results indicate that the RMI phenomenon markedly enhances the mixing efficiency (up to 43%, which is necessary to initiate the chemical reactions. Ground experiments were carried out in the combustor, which verify the numerical method from the perspective of wall pressures of the combustor. In particular, the experiment results indicate that the RMI can benefit flame-holding due to the mixing enhancement.

  3. Atomically thin Pt shells on Au nanoparticle cores: facile synthesis and efficient synergetic catalysis

    Engelbrekt, Christian; Seselj, Nedjeljko; Poreddy, Raju


    We present a facile synthesis protocol for atomically thin platinum (Pt) shells on top of gold (Au) nanoparticles (NPs) (Au@PtNPs) in one pot under mild conditions. The Au@PtNPs exhibited remarkable stability (> 2 years) at room temperature. The synthesis, bimetallic nanostructures and catalytic...... clearly show that the active surface is dominated by Pt with a specific surface area above 45 m2 per gram of Pt. Interactions with the Au core increase the activity of the Pt shell by up to 55% and improve catalytic selectivity compared to pure Pt. The Au@Pt NPs show exciting catalytic activity...

  4. Axially connected nanowire core-shell p-n junctions: a composite structure for high-efficiency solar cells.

    Wang, Sijia; Yan, Xin; Zhang, Xia; Li, Junshuai; Ren, Xiaomin


    A composite nanostructure for high-efficiency solar cells that axially connects nanowire core-shell p-n junctions is proposed. By axially connecting the p-n junctions in one nanowire, the solar spectrum is separated and absorbed in the top and bottom cells with respect to the wavelength. The unique structure of nanowire p-n junctions enables substantial light absorption along the nanowire and efficient radial carrier separation and collection. A coupled three-dimensional optoelectronic simulation is used to evaluate the performance of the structure. With an excellent current matching, a promising efficiency of 19.9% can be achieved at a low filling ratio of 0.283 (the density of the nanowire array), which is much higher than the tandem axial p-n junctions.

  5. Au@polymer core-shell nanoparticles for simultaneously enhancing efficiency and ambient stability of organic optoelectronic devices.

    Kim, Taesu; Kang, Hyunbum; Jeong, Seonju; Kang, Dong Jin; Lee, Changyeon; Lee, Chun-Ho; Seo, Min-Kyo; Lee, Jung-Yong; Kim, Bumjoon J


    In this paper, we report and discuss our successful synthesis of monodispersed, polystyrene-coated gold core-shell nanoparticles (Au@PS NPs) for use in highly efficient, air-stable, organic light-emitting diodes (OLEDs) and organic photovoltaics (OPVs). These core-shell NPs retain the dual functions of (1) the plasmonic effect of the Au core and (2) the stability and solvent resistance of the cross-linked PS shell. The monodispersed Au@PS NPs were incorporated into a poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) film that was located between the ITO substrate and the emitting layer (or active layer) in the devices. The incorporation of the Au@PS NPs provided remarkable improvements in the performances of both OLEDs and OPVs, which benefitted from the plasmonic effect of the Au@PS NPs. The OLED device with the Au@PS NPs achieved an enhancement of the current efficiency that was 42% greater than that of the control device. In addition, the power conversion efficiency was increased from 7.6% to 8.4% in PTB7:PC71BM-based OPVs when the Au@PS NPs were embedded. Direct evidence of the plasmonic effect on optical enhancement of the device was provided by near-field scanning optical microscopy measurements. More importantly, the Au@PS NPs induced a remarkable and simultaneous improvement in the stabilities of the OLED and OPV devices by reducing the acidic and hygroscopic properties of the PEDOT:PSS layer.

  6. Effects of diffusion coefficients and struts apposition using numerical simulations for drug eluting coronary stents.

    Mongrain, Rosaire; Faik, Isam; Leask, Richard L; Rodés-Cabau, Josep; Larose, Eric; Bertrand, Olivier F


    In the context of drug eluting stent, we present two-dimensional numerical models of mass transport of the drug in the wall and in the lumen to study the effect of the drug diffusion coefficients in the three principal media (blood, vascular wall, and polymer coating treated as a three-compartment problem) and the impact of different strut apposition configurations (fully embedded, half embedded, and not embedded). The different conditions were analyzed in terms of their consequence on the drug concentration distribution in the arterial wall. We apply the concept of the therapeutic window to the targeted vascular wall region and derive simple metrics to assess the efficiency of the various stent configurations. Although most of the drug is dispersed in the lumen, variations in the blood flow rate within the physiological range of coronary blood flow and the diffusivity of the drug molecule in the blood were shown to have a negligible effect on the amount of drug in the wall. Our results reveal that the amount of drug cumulated in the wall depends essentially on the relative values of the diffusion coefficients in the polymer coating and in the wall. Concerning the strut apposition, it is shown that the fully embedded strut configuration would provide a better concentration distribution.

  7. High-efficiency CdTe/CdS core/shell nanocrystals in water enabled by photo-induced colloidal hetero-epitaxy of CdS shelling at room temperature

    Hakimeh Zare[1; Maziar Marandi[2; Somayeh Fardindoost[1; Vijay Kumar Sharma[3,4; Aydan Yeltik[3; Omid Akhavan[1,5; Hilmi Volkan Demir[3,4; Nima Taghavinia[1,5


    We report high-efficiency CdTe/CdS core/shell nanocrystals synthesized in water by epitaxially growing CdS shells on aqueous CdTe cores at room temperature, enabled by the controlled release of S species under low-intensity ultraviolet (UV) light illumination. The resulting photo-induced dissociation of S2O2- ions conveniently triggers the formation of critical two-dimensional CdS epitaxy on the CdTe surface at room temperature, as opposed to initiating the growth of individual CdS core-only nanocrystals. This controlled colloidal hetero-epitaxy leads to a substantial increase in the photoluminescence (PL) quantum yield (QY) of the shelled nanocrystals in water (reaching 64%). With a systematic set of studies, the maximum PL QY is found to be almost independent of the illuminating UV intensity, while the shell formation kinetics required for reaching the maximum QY linearly depends on the illuminating UV intensity. A stability study of the QD films in air at various temperatures shows highly improved thermal stability of the shelled QDs (up to 120 ℃ in ambient air). These results indicate that the proposed aqueous CdTe/CdS core/shell nanocrystals hold great promise for applications requiring efficiency and stability.

  8. Synthesis of LiFePO4@carbon nanotube core-shell nanowires with a high-energy efficient method for superior lithium ion battery cathodes

    Wang, Guiling; Ma, Zhipeng; Shao, Guangjie; Kong, Lingxue; Gao, Weimin


    A high-energy efficient method is developed for the synthesis of LiFePO4@CNT core-shell nanowire structures. The method consists of two steps: liquid deposition approach to prepare FePO4@CNT core-shell nanowires and solvothermal lithiation to obtain the LiFePO4@CNT core-shell nanowires at a low temperature. The solution phase method can be easily scaled up for commercial application. The performance of the materials produced by this method is evaluated in Li ion batteries. The one-dimensional LiFePO4@CNT nanowires offer a stable and efficient backbone for electron transport. The LiFePO4@CNT core-shell nanowires exhibit a high capacity of 132.8 mAh g-1 at a rate of 0.2C, as well as high rate capability (64.4 mAh g-1 at 20C) for Li ion storage.

  9. 基于Struts2+jQuery+JSON实现Ajax数据显示%Implementation of Ajax Data Display Based on Struts2+jQuery+JSON



    Through asynchronous interaction technology, Ajax enchances the transmission efficiency and the speed of response between the server and the client side based on the B/S application. Introduces how to bring about the Ajax function by utilizing the intergerated framework of Struts2 and jQuery as well as JSON data format., the development of Web system change easier, more efficient. Through the example of data display expound the realization process.%Ajax通过异步交互技术,提高在B/S模式下服务器与客户端之间的传输效率和响应速度。通过整合Struts2框架、jQuery框架以及JSON数据格式,介绍如何实现Ajax功能,使Web系统开发变得更容易、更有效率,并通过数据显示实例讲解了实现过程。

  10. Experimental investigation on combustion performance of cavity-strut injection of supercritical kerosene in supersonic model combustor

    Sun, Ming-bo; Zhong, Zhan; Liang, Jian-han; Wang, Hong-bo


    Supersonic combustion with cavity-strut injection of supercritical kerosene in a model scramjet engine was experimentally investigated in Mach 2.92 facility with the stagnation temperatures of approximately 1430 K. Static pressure distribution in the axial direction was determined using pressure transducers installed along the centerline of the model combustor top walls. High speed imaging camera was used to capture flame luminosity and combustion region distribution. Multi-cavities were used to and stabilize the combustion in the supersonic combustor. Intrusive injection by thin struts was used to enhance the fuel-air mixing. Supercritical kerosene at temperatures of approximately 780 K and various pressures was prepared using a heat exchanger driven by the hot gas from a pre-burner and injected at equivalence ratios of approximately 1.0. In the experiments, combustor performances with different strut injection schemes were investigated and compared to direct wall injection scheme based on the measured static pressure distributions, the specific thrust increments and the images obtained by high-speed imaging camera. The experimental results showed that the injection by thin struts could obtain an enhanced mixing in the field but could not acquire a steady flame when mixing field cannot well match cavity separation region. There is no significant difference on performance between different schemes since the unsteady intermittent and oscillating flame leads to no actual combustion efficiency improvement.

  11. Platinum-tin oxide core-shell catalysts for efficient electro-oxidation of ethanol.

    Du, Wenxin; Yang, Guangxing; Wong, Emily; Deskins, N Aaron; Frenkel, Anatoly I; Su, Dong; Teng, Xiaowei


    Platinum-tin (Pt/Sn) binary nanoparticles are active electrocatalysts for the ethanol oxidation reaction (EOR), but inactive for splitting the C-C bond of ethanol to CO2. Here we studied detailed structure properties of Pt/Sn catalysts for the EOR, especially CO2 generation in situ using a CO2 microelectrode. We found that composition and crystalline structure of the tin element played important roles in the CO2 generation: non-alloyed Pt46-(SnO2)54 core-shell particles demonstrated a strong capability for C-C bond breaking of ethanol than pure Pt and intermetallic Pt/Sn, showing 4.1 times higher CO2 peak partial pressure generated from EOR than commercial Pt/C.

  12. Highly efficient biosensors by using well-ordered ZnO/ZnS core/shell nanotube arrays.

    Tarish, Samar; Xu, Yang; Wang, Zhijie; Mate, Faten; Al-Haddad, Ahmed; Wang, Wenxin; Lei, Yong


    We have studied the fabrication of highly efficient glucose sensors using well-ordered heterogeneous ZnO/ZnS core/shell nanotube arrays (CSNAs). The modified electrodes exhibit a superior electrochemical response towards ferrocyanide/ferricyanide and in glucose sensing. Further, the fabricated glucose biosensor exhibited good performance over an acceptable linear range from 2.39 × 10(-5) to 2.66 × 10(-4) mM, with a sensitivity of 188.34 mA mM(-1) cm(-2), which is higher than that of the ZnO nanotube array counterpart. A low limit of detection was realized (24 μM), which is good compared with electrodes based on conventional structures. In addition, the enhanced direct electrochemistry of glucose oxidase indicates the fast electron transfer of ZnO/ZnS CSNA electrodes, with a heterogeneous electron transfer rate constant (K s) of 1.69 s(-1). The fast electron transfer is attributed to the high conductivity of the modified electrodes. The presented ZnS shell can facilitate the construction of future sensors and enhance the ZnO surface in a biological environment.

  13. Highly efficient biosensors by using well-ordered ZnO/ZnS core/shell nanotube arrays

    Tarish, Samar; Xu, Yang; Wang, Zhijie; Mate, Faten; Al-Haddad, Ahmed; Wang, Wenxin; Lei, Yong


    We have studied the fabrication of highly efficient glucose sensors using well-ordered heterogeneous ZnO/ZnS core/shell nanotube arrays (CSNAs). The modified electrodes exhibit a superior electrochemical response towards ferrocyanide/ferricyanide and in glucose sensing. Further, the fabricated glucose biosensor exhibited good performance over an acceptable linear range from 2.39 × 10‑5 to 2.66 × 10‑4 mM, with a sensitivity of 188.34 mA mM‑1 cm‑2, which is higher than that of the ZnO nanotube array counterpart. A low limit of detection was realized (24 μM), which is good compared with electrodes based on conventional structures. In addition, the enhanced direct electrochemistry of glucose oxidase indicates the fast electron transfer of ZnO/ZnS CSNA electrodes, with a heterogeneous electron transfer rate constant (K s) of 1.69 s‑1. The fast electron transfer is attributed to the high conductivity of the modified electrodes. The presented ZnS shell can facilitate the construction of future sensors and enhance the ZnO surface in a biological environment.

  14. Highly efficient near-infrared light-emitting diodes by using type-II CdTe/CdSe core/shell quantum dots as a phosphor.

    Shen, Huaibin; Zheng, Ying; Wang, Hongzhe; Xu, Weiwei; Qian, Lei; Yang, Yixing; Titov, Alexandre; Hyvonen, Jake; Li, Lin Song


    In this paper, we present an innovative method for the synthesis of CdTe/CdSe type-II core/shell structure quantum dots (QDs) using 'greener' chemicals. The PL of CdTe/CdSe type-II core/shell structure QDs ranges from 600 to 820 nm, and the as-synthesized core/shell structures show narrow size distributions and stable and high quantum yields (50–75%). Highly efficient near-infrared light-emitting diodes (LEDs) have been demonstrated by employing the CdTe/CdSe type-II core/shell QDs as emitters. The devices fabricated based on these type-II core/shell QDs show color-saturated near-infrared emission from the QD layers, a low turn-on voltage of 1.55 V, an external quantum efficiency (EQE) of 1.59%, and a current density and maximum radiant emittance of 2.1 × 10(3) mA cm−2 and 17.7 mW cm−2 at 8 V; it is the first report to use type-II core/shell QDs as near-infrared emitters and these results may offer a practicable platform for the realization of near-infrared QD-based light-emitting diodes, night-vision-readable displays, and friend/foe identification system.


    André Liebscher


    Full Text Available Open cell foams are formed by an interconnected network of struts whose thickness varies locally. These variations were shown to have an impact on the elastic and thermal properties of the foam. In this paper we quantify the local strut thickness by means of micro computed tomography (µCT imaging. We introduce a skeletonization based topological decomposition of the foam structure into its vertices and struts. This allows to estimate the thickness of individual strut segments by the Euclidean distance transform, where an appropriate correction for struts with nonspherical cross-sectional shape is applied. Conflating these estimates based on the strut lengths results in a strut thickness profile for the entire foam. Polynomial models for the strut thickness profile are investigated by means of a regression analysis.

  16. Effect of shear and magnetic field on the heat-transfer efficiency of convection in rotating spherical shells

    Yadav, Rakesh K; Christensen, Ulrich R; Duarte, Lucia; Reiners, Ansgar


    We study rotating thermal convection in spherical shells as prototype for flow in the cores of terrestrial planets, gas planets or in stars. We base our analysis on a set of about 450 direct numerical simulations of the (magneto)hydrodynamic equations under the Boussinesq approximation. The Ekman number ranges from $10^{-3}$ to $10^{-6}$. Four sets of simulations are considered: non-magnetic simulations and dynamo simulations with either free-slip or no-slip flow boundary conditions. The non-magnetic setup with free-slip boundaries generates the strongest zonal flows. Both non-magnetic simulations with no-slip flow boundary conditions and self-consistent dynamos with free-slip boundaries have drastically reduced zonal-flows. Suppression of shear leads to a substantial gain in heat-transfer efficiency, increasing by a factor of 3 in some cases. Such efficiency enhancement occurs as long as the convection is significantly influenced by rotation. At higher convective driving the heat-transfer efficiency trends t...

  17. An upconversion NaYF4:Yb3+,Er3+/TiO2 core-shell nanoparticle photoelectrode for improved efficiencies of dye-sensitized solar cells

    Zhang, Jun; Shen, Haiou; Guo, Wei; Wang, Shunhao; Zhu, Chuntao; Xue, Fang; Hou, Jinfeng; Su, Haiquan; Yuan, Zhuobin


    Novel upconversion NaYF4:Yb3+,Er3+/TiO2 core-shell nanoparticles (NPs) are synthesized and used to prepare the photoelectrode (PE) of dye-sensitized solar cells (DSSCs). The morphology, structure, photoluminescence characterization of the NaYF4:Yb3+,Er3+/TiO2 core-shell NPs and the photoelectric performance, alternating current impedance spectroscopy of DSSCs are characterized using transmission electron microscopy, X-ray diffraction, upconversion luminescence (UCL) spectrofluorimetry and electrochemistry. Compared with the pure TiO2 PE or the NaYF4:Yb3+,Er3+ upconversion NPs and TiO2 simply mixed prepared PE as the volume ratio of the core-shell structure, the DSSCs with the upconversion core-shell PE show a greater photovoltaic efficiency. The energy conversion efficiency of the DSSCs with a NaYF4:Yb3+,Er3+/TiO2 PE is 23.1% higher than with a pure TiO2 PE and 99.1% higher than with a mixed PE using the same conditions. This enhancement is due to the UCL core extending the spectral response range of DSSCs to the infrared region and their particular shell structure, retaining its semiconductor character. This method represents a novel approach to increase the efficiencies of DSSCs.

  18. Long range node-strut analysis of trabecular bone microarchitecture

    Schmah, T; Thomsen, J S; Saparin, P


    Purpose: We present a new morphometric measure of trabecular bone microarchitecture, called mean node strength (NdStr), which is part of a newly developed approach called long range node-strut analysis. Our general aim is to describe and quantify the apparent "latticelike" microarchitecture of the trabecular bone network. Methods: Similar in some ways to the topological node-strut analysis introduced by Garrahan et al. [J. Microsc. 142, 341-349 (1986)], our method is distinguished by an emphasis on long-range trabecular connectivity. Thus, while the topological classification of a pixel (after skeletonization) as a node, strut, or terminus, can be determined from the 3x3 neighborhood of that pixel, our method, which does not involve skeletonization, takes into account a much larger neighborhood. In addition, rather than giving a discrete classification of each pixel as a node, strut, or terminus, our method produces a continuous variable, node strength. The node strength is averaged over a region of interest ...

  19. Long range node-strut analysis of trabecular bone microarchitecture

    Schmah, Tanya; Marwan, Norbert; Thomsen, Jesper Skovhus


    PURPOSE: We present a new morphometric measure of trabecular bone microarchitecture, called mean node strength (NdStr), which is part of a newly developed approach called long range node-strut analysis. Our general aim is to describe and quantify the apparent "latticelike" microarchitecture of th...

  20. Designing Struts for the Low-Fidelity Orion Cockpit Mockup

    Lucienne, Runa A.


    The objective of the project was to design and construct nine struts to be installed in the low-fidelity Orion cockpit mockup (Rev F; located at NASA s Johnson Space Center in Houston, TX) as simplified representations of the existing flight designed struts designed by engineers at Lockheed Martin (the primary contractor of the Orion). The project design included: researching the existing flight designs, brainstorming design upgrades, developing three unrelated three-dimensional (3D) strut designs using Pro/Engineer Wildfire 3.0, choosing the best fit design, locating materials and their sources, implementing the chosen design, and making design modifications. The project resulted in making simple modifications to the existing struts used in the last Orion cockpit mockup. The project is relevant to NASA, because upgrades to the low-fidelity Orion cockpit mockup progresses NASA s goals of developing and testing a new spacecraft, conducting the spacecraft's first crewed mission by 2015, returning to the moon by 2020, and exploring Mars and other planets in the future.

  1. Aerodynamic Theory and Tests of Strut Forms-II

    Smith, R H


    This report presents the second of two studies under the same title. In this part five theoretical struts are developed from distributed sources and sinks and constructed for pressure and resistance tests in a wind tunnel. The surface pressures for symmetrical inviscid flow are computed for each strut from theory and compared with those found by experiment. The theoretical and experimental pressures are found to agree quantitatively near the bow, only qualitatively over the suction range, the experimental suctions being uniformly a little low, and not at all near the stern. This study is the strut sequel to Fuhrmann's research on airship forms, the one being a study in two dimensions, the other in three. A comparison of results indicates that the agreement between theory and experiment is somewhat better for bodies of revolution than for cylinders when both are shaped for slight resistance. The consistent deficiency of the experimental suctions which is found in the case of struts was not found in the case of airships, for which the experimental suctions were sometimes above sometimes below their theoretical values.

  2. Pd-Ir Core-Shell Nanocubes: A Type of Highly Efficient and Versatile Peroxidase Mimic.

    Xia, Xiaohu; Zhang, Jingtuo; Lu, Ning; Kim, Moon J; Ghale, Kushal; Xu, Ye; McKenzie, Erin; Liu, Jiabin; Ye, Haihang


    Peroxidase mimics with dimensions on the nanoscale have received great interest as emerging artificial enzymes for biomedicine and environmental protection. While a variety of peroxidase mimics have been actively developed recently, limited progress has been made toward improving their catalytic efficiency. In this study, we report a type of highly efficient peroxidase mimic that was engineered by depositing Ir atoms as ultrathin skins (a few atomic layers) on Pd nanocubes (i.e., Pd-Ir cubes). The Pd-Ir cubes exhibited significantly enhanced efficiency, with catalytic constants more than 20- and 400-fold higher than those of the initial Pd cubes and horseradish peroxidase (HRP), respectively. As a proof-of-concept demonstration, the Pd-Ir cubes were applied to the colorimetric enzyme-linked immunosorbent assay (ELISA) of human prostate surface antigen (PSA) with a detection limit of 0.67 pg/mL, which is ∼110-fold lower than that of the conventional HRP-based ELISA using the same set of antibodies and the same procedure.

  3. Influence of photo-luminescent CdSe/CdS core shell quantum dots in solar cell efficiency

    Lopez-Delgado, R.; Zhou, Y.; Zazueta-Raynaud, A.; Zhao, H.; Pelayo, J. E.; Vomiero, A.; Álvarez-Ramos, M. E.; Rosei, F.; Ayon, A.


    We report the synthesis and characterization of CdSe/CdS core-shell quantum dots (CdSe/CdS-QDs) that exhibit absorption in the UV range of the solar spectrum and emit photons with wavelengths centered around 625 nm, a wavelength that is well suited for silicon absorption and electron-hole pair generation. We also report the fabrication and characterization of single crystal silicon (c-Si) solar cells with and without the aforementioned photo luminescent, down-shifting CdSe/CdS- QDs. The incorporation of these nanostructures triggered improvements in the performance of the devices, particularly in the open circuit voltage (Voc) and short circuit current density (Jsc) for which the measured values showed an increase from 543 to 546 mV and from 32.5 to 37.0 mA/cm2, respectively. The combined effect of the improved values led to an increment in the power conversion efficiency (PCE) from 12.01 to 13.54%. This increase represents a 12.7% improvement in the PCE of the fabricated devices. The effort described herein is considered a good fit to the generalized trend to improve the efficiency of solar cells with mass-compatible techniques that could serve to promote their widespread utilization.

  4. Utilization of Pine Nut Shell derived carbon as an efficient alternate for the sequestration of phthalates from aqueous system

    Umair A. Qureshi


    Full Text Available This study highlights the importance of a cheap bio waste; Pine Nut Shell (PNS, from which a carbon is synthesized that can efficiently remove toxic phthalates from an aqueous system. PNS derived carbon shows high affinity toward phthalates in descending order along with adsorption capacity i.e., dibutyl phthalate (DBP 5.65 mg/g > diallyl phthalate (DAP 3.64 mg/g > diethyl phthalate (DEP and 2.87 mg/g > dimethyl phthalate (DMP 2.48 mg/g. Different characterization techniques such as FTIR, elemental analysis, point of zero electric charge (PZC, SEM, EDX and BET were employed to investigate the binding sites and surface area of the adsorbent. Adsorption experiments were performed both in batch and column modes. Equilibrium studies showed that the Langmuir isotherm fits best to experimental data. Kinetically, adsorption phenomena obeyed pseudo second order. Furthermore, thermodynamic results expressed the exothermic nature of adsorption on the basis of negative value of enthalpy change. Column sorption method was also adapted to check the feasibility of the adsorption process through the investigation of flow rate, breakthrough curve and pre-concentration factor which is found to be 13 for DMP and DEP and 16 for DAP and DBP. Methanol was found to be best solvent for the recovery of phthalates. Application in real water samples also showed good efficiency of PNS derived carbon for the removal of phthalates.


    Durmuş TÜRKMEN


    Full Text Available The experiment was carried out to investigate the phenomenon of buckling using simple struts. These results were then compared with the theoretical predictions. Three steel struts of different length were used in the experiment; one of them had fix/pinned-end all the others had pin/pin-end joint. The applied load was placed at different eccentricities for each strut. Six aluminium pin-end struts of varying length were also tested. The measured critical load for each strut was compared against the corresponding Euler and Southwell predictions. For a steel strut, it would be expected that buckling would be symmetrical for left and right eccentricities. However, this was not the case due to imperfections in the struts. The struts buckled with half sine-wave and if one end of the strut was fixed the effective length was reduced and the critical load was increased. In the case of the aluminium struts, due to plastic behaviour in the deformation it was much harder to find the critical load. For steel struts both Euler and Southwell predictions were close to initial estimates of critical load.

  6. Efficient protection and transfection of small interfering RNA by cationic shell-crosslinked knedel-like nanoparticles.

    Shen, Yuefei; Fang, Huafeng; Zhang, Ke; Shrestha, Ritu; Wooley, Karen L; Taylor, John-Stephen A


    Despite the great potential of small interfering RNA (siRNA) as a therapeutic agent, progress in this area has been hampered by a lack of efficient biocompatible transfection agents. Recently, cationic shell-crosslinked knedel-like nanoparticles (cSCKs) were found to possess lower cytotoxicity and better transfection ability for phosphorothioate ODNs and plasmid DNA than the commonly used cationic lipid-based agent Lipofectamine. To determine the usefulness of cSCKs for siRNA transfection, a small library of cSCKs with varying percentage of primary and tertiary amines was assessed for its ability to bind to siRNA, inhibit siRNA degradation in human serum, and to transfect HeLa and mouse macrophage cell lines. The silencing efficiency in HeLa cells was greatest with the cSCK with 100% primary amines (pa100) as determined by their viability following transfection with cytotoxic and non-cytotoxic siRNAs. cSCK-pa100 showed greater silencing efficiency than Lipofectamine 2000 in the HeLa cells, as well in 293T and human bronchial epithelial (HEK) cells, but was comparable in human bronchial epithelial (BEAS-2B) cells and human mammary epithelial (MCF10a) cells. cSCK-pa100 also showed greater silencing of iNOS expression than Lipofectamine 2000 in a mouse macrophage cell line, and provided greater protection from serum degradation, demonstrating its potential usefulness as an siRNA transfection agent. The siRNA silencing of iNOS at lower concentrations of siRNA could be enhanced by complexation with the fusogenic GALA peptide, which was shown to enhance endosomal escape following uptake.

  7. Synthesis of core-shell heterostructured Cu/Cu2O nanowires monitored by in situ XRD as efficient visible-light photocatalysts

    Chen, Wei


    Core-shell heterostructured Cu/Cu2O nanowires with a high aspect ratio were synthesized from Cu foam using a novel oxidation/reduction process. In situ XRD was used as an efficient tool to acquire phase transformation details during the temperature-programmed oxidation of Cu foam and the subsequent reduction process. Based on knowledge of the crucial phase transformation, optimal synthesis conditions for producing high-quality CuO and core-shell Cu/Cu2O nanowires were determined. In favor of efficient charge separation induced by the special core-shell heterostructure and the advanced three-dimensional spatial configuration, Cu/Cu2O nanowires exhibited superior visible-light activity in the degradation of methylene blue. The present study illustrates a novel strategy for fabricating efficiently core-shell heterostructured nanowires and provides the potential for developing their applications in electronic devices, for environmental remediation and in solar energy utilization fields. This journal is © The Royal Society of Chemistry.

  8. Pd@Pt Core–Shell Nanoparticles with Branched Dandelion-like Morphology as Highly Efficient Catalysts for Olefin Reduction

    A facile synthesis based on the addition of ascorbic acid to a mixture of Na2PdCl4, K2PtCl6, and Pluronic P123 results in highly branched core–shell nanoparticles (NPs) with a micro–mesoporous dandelion-like morphology comprising Pd core and Pt shell. The slow reduction kinetics ...

  9. Pd@Pt Core–Shell Nanoparticles with Branched Dandelion-like Morphology as Highly Efficient Catalysts for Olefin Reduction

    A facile synthesis based on the addition of ascorbic acid to a mixture of Na2PdCl4, K2PtCl6, and Pluronic P123 results in highly branched core–shell nanoparticles (NPs) with a micro–mesoporous dandelion-like morphology comprising Pd core and Pt shell. The slow reduction kinetics ...

  10. A comparison of knee-ankle-foot orthoses with either metal struts or an adjustable posterior strut in hemiplegic stroke patients.

    Maeshima, Shinichiro; Okazaki, Hideto; Okamoto, Sayaka; Mizuno, Shiho; Asano, Naoki; Maeda, Hirofumi; Masaki, Mitsuko; Matsuo, Hiroshi; Tsunoda, Tetsuya; Sonoda, Shigeru


    We investigated differences in factors affecting judgments regarding the creation of new adjustable posterior strut knee-ankle-foot orthoses (APS-KAFO) and knee-ankle-foot orthoses with metal struts (traditional KAFO) for hemiplegic stroke patients for whom KAFO were created in rehabilitation wards. Subjects were 50 patients with hemiplegia due to new-onset stroke (cerebral infarction: n = 25, cerebral hemorrhage: n = 25) who were prescribed KAFO. Patient ages ranged from 36 to 90 years, and the mean duration from stroke onset to hospitalization was 28.8 ± 13.8 days. Neurologic symptoms, cognitive function, activities of daily living, duration from hospitalization to orthosis creation, hospitalization duration, walking ability at discharge, outcome after discharge, and so forth were compared. Fourteen patients were prescribed APS-KAFO, and 36 were prescribed traditional KAFO. Those prescribed APS-KAFO had somewhat milder neurologic symptoms and cognitive dysfunction and a shorter hospitalization duration than those prescribed traditional KAFO. Patients prescribed APS-KAFO also had a higher score and efficiency on functional independence measure at admission and discharge. Walking independence at discharge was seen in 8 of the 14 patients for whom APS-KAFO were created and 8 of the 36 patients for whom traditional KAFO were created. APS-KAFO was chosen for patients with a high level of activity in the ward and with a higher likelihood of acquiring walking ability using APS-AFO at discharge, whereas traditional KAFO tended to be chosen for patients with relatively severe symptoms who were not expected to acquire practical walking ability. Copyright © 2015 National Stroke Association. Published by Elsevier Inc. All rights reserved.

  11. Technical Textiles to Strut Their Stuff


    Will geotextiles soon be successfully creating fertile soil from arid desert landscapes? Will creative forms in mobility make it possible for even more people to be transported efficiently in the near future? Will textiles a few years from now be able to open up new habitats for humanity on distant planets? Will textiles be made safe against a spark that might sparkle into a conflagration in high-rise cities? The answers to these and many other exciting questions relating to visionary textiles production are all being researched in the field of technical textiles.

  12. Efficiency Enhanced Colloidal Mn-Doped Type II Core/Shell ZnSe/CdS Quantum Dot Sensitized Hybrid Solar Cells

    A. Jamshidi


    Full Text Available Colloidal Mn-doped ZnSe/CdS core/shell quantum dots (QDs are synthesized for the first time and employed as a strategy to boost the power conversion efficiency of quantum dot sensitized solar cells. By using Mn-doping as a band gap engineering tool for core/shell QDs an effective improvement of absorption spectra could be obtained. The mid-states generated by a proper Mn content alleviate carrier separation and enhance the electron injection rate, thus facilitating electron transport to the TiO2 substrate. It is demonstrated that a device constructed with 0.25% Mn-doped ZnSe/CdS leads to an enhancement of the electron injection rate and power conversion efficiency by 4 times and 1.3, respectively.

  13. An efficient room temperature core-shell AgPd@MOF catalyst for hydrogen production from formic acid

    Ke, Fei; Wang, Luhuan; Zhu, Junfa


    Novel core-shell AgPd@MIL-100(Fe) NPs were fabricated by a facile one-pot method. Significantly, the as-prepared core-shell NPs exhibit much higher catalytic activity than the pure AgPd NPs toward hydrogen production from formic acid without using any additive at room temperature.Novel core-shell AgPd@MIL-100(Fe) NPs were fabricated by a facile one-pot method. Significantly, the as-prepared core-shell NPs exhibit much higher catalytic activity than the pure AgPd NPs toward hydrogen production from formic acid without using any additive at room temperature. Electronic supplementary information (ESI) available. See DOI: 10.1039/c4nr07582j

  14. Facile synthesis of highly efficient one-dimensional plasmonic photocatalysts through Ag@Cu₂O core-shell heteronanowires.

    Xiong, Jinyan; Li, Zhen; Chen, Jun; Zhang, Shanqing; Wang, Lianzhou; Dou, Shixue


    A novel class of one-dimensional (1D) plasmonic Ag@Cu2O core-shell heteronanowires have been synthesized at room temperature for photocatalysis application. The morphology, size, crystal structure and composition of the products were investigated by XRD, SEM, TEM, XPS, and UV-vis instruments. It was found the reaction time and the amount of Ag nanowires play crucial roles in the formation of well-defined 1D Ag@Cu2O core-shell heteronanowires. The resultant 1D Ag@Cu2O NWs exhibit much higher photocatalytic activity toward degradation of organic contaminants than Ag@Cu2O core-shell nanoparticles or pure Cu2O nanospheres under solar light irradiation. The drastic enhancement in photocatalytic activity could be attributed to the surface plasmon resonance and the electron sink effect of the Ag NW cores, and the unique 1D core-shell nanostructure.

  15. Excited states of large open-shell molecules: an efficient, general, and spin-adapted approach based on a restricted open-shell ground state wave function.

    Roemelt, Michael; Neese, Frank


    A spin-adapted configuration interaction with singles method that is based on a restricted open-shell reference function (ROCIS) with general total spin S is presented. All excited configuration state functions (CSFs) are generated with the aid of a spin-free second quantization formalism that only leads to CSFs within the first order interacting space. By virtue of the CSF construction, the formalism involves higher than singly excited determinants but not higher than singly excited configurations. Matrix elements between CSFs are evaluated on the basis of commutator relationships using a symbolic algebra program. The final equations were, however, hand-coded in order to maximize performance. The method can be applied to fairly large systems with more than 100 atoms in reasonable wall-clock times and also parallelizes well. Test calculations demonstrate that the approach is far superior to UHF-based configuration interaction with single excitations but necessarily falls somewhat short of quantitative accuracy due to the lack of dynamic correlation contributions. In order to implicitly account for dynamic correlation in a crude way, the program optionally allows for the use of Kohn-Sham orbitals in combination with a modest downscaling of two-electron integrals (DFT/ROCIS). All two-electron integrals of Kohn-Sham orbitals that appear in the Hamiltonian matrix are reduced by a total of three scaling parameters that are suitable for a wide range of molecules. Test calculations on open-shell organic radicals as well as transition metal complexes demonstrate the wide applicability of the method and its ability to calculate the electronic spectra of large molecular systems.

  16. Carbon-shell-decorated p-semiconductor PbMoO4 nanocrystals for efficient and stable photocathode of photoelectrochemical water reduction

    Wang, Ligang; Tang, Hanqin; Tian, Yang


    Photoelectrochemical (PEC) water splitting using semiconductors is a promising method for the future scalable production of renewable hydrogen fuels. The critical issues in PEC water splitting include the development of the photoelectrode materials with high efficiency and long-term stability, especially for p-type semiconductor photocathodes. Herein, we report the use of citric acid (CA) pyrolysis to prepare carbon-shell-decorated PbMoO4 (C@PbMoO4) nanocrystals via a simple solvothermal method. Different carbon shell thicknesses below 10 nm were generated by varying the amount of CA in the precursor solution. In contrast, without using CA, bare PbMoO4 nanocrystals were obtained. The PEC experiments showed that 2-nm carbon shell could preferably improve the water splitting performance of PbMoO4: the photocurrent density of 2-nm C@PbMoO4 is nearly 2-fold high as that of bare PbMoO4 at 0 V versus reversible hydrogen electrode (RHE). The surface charge transfer efficiency of 2-nm C@PbMoO4 in the PEC process was tested to increase from 83% to 90.4%, the charge separation efficiency enhanced 56%, and the PEC stability also greatly increased compared to those of the bare PbMoO4 nanocrystals. This strategy could be applied to other p-type semiconducting photocathodes for low-cost solar-fuel-generation devices.

  17. Sequestering Potential of Peach Nut Shells as an Efficient Sorbent for Sequestering Some Toxic Metal Ions from Aqueous Waste: A Kinetic and Thermodynamic Study

    Muhammad Ashraf Shaheen


    Full Text Available The peach nut shells potential as a low cost biosorbent for separation of certain metal ions from aqueous media was investigated. The effects of different parameters such as pH, shaking speed, initial metal ions concentration and their contact time with adsorbent on sorption efficiency of biosorbent was investigated to optimize the parameters for maximum sorption. The FT–IR spectroscopy and TGA were used to characterize the biosorbent. A significant increase in sorption was noted with rise in pH of metal ions solution and maximum sorption was observed at pH 6. The isothermal data was fitted to Langmuir, Dubinin–Radushkevich (D–R, Freundlich isotherms and equilibrium process was best fitted to Langmuir isotherm. The removal efficiency of chemically activated samples was found to be ~35 to 45% greater than raw sample. The results showed that peach nut shell was an effective biosorbent for the remediation of the contaminated water with lead (II, Nickle (II and Chromium (III ions. Being low cost material, PNS has a potential to be exploited in waste water treatment technologies. This study shows that activated PNS exhibited appreciable sorption for Pb, Cr and Ni metals ions (97%, 95% and 94% respectively from aqueous solution even at very low concentration of sorbent. The chemical and thermal activation of peach nut shells enhances the removal efficiency for all the metal ions and from the reported data; it was found that the adsorption ability of Pb ions was greater than nickel and chromium.

  18. One-step synthesis of novel PANI-Fe3O4@ZnO core-shell microspheres: An efficient photocatalyst under visible light irradiation

    Zhang, Xiaoyuan; Wu, Jianning; Meng, Guihua; Guo, Xuhong; Liu, Chang; Liu, Zhiyong


    For the first time, novel multifunctional superparamagnetic PANI-Fe3O4@ZnO core-shell composite photocatalysts with different PANI: ZnO ratios were synthesized by Pickering emulsion route in one step in the presence of ZnO nanoparticles. PANI-Fe3O4@ZnO core-shell microspheres consist of PANI core which embedded with Fe3O4-OA (oleic acid modified Fe3O4) nanoparticles and tunable ZnO shell thickness. The resulting samples were thoroughly studied by using X-ray diffraction (XRD), X-ray photoelectron spectra (XPS), transmission electron microscopy (TEM), scanning electron microscope (SEM) and energy dispersive X-ray spectroscopy (EDS). The catalytic activity of the as-prepared PANI-Fe3O4@ZnO core-shell microspheres is investigated by the degradation of MB under visible light irradiation. As expected, the as prepared PANI-Fe3O4@ZnO photocatalysts exhibit highly enhanced photocatalytic activities in the degradation of MB under visible light irradiation owing to fast separation of photo-generated electron-hole pairs. Significantly, the PANI-Fe3O4@ZnO catalysts can be separated from the reaction media by applying an external magnet, and can be reused for seven cycles without change in stability and degradation efficiency.

  19. High-efficiency and mechano-/photo- bi-catalysis of piezoelectric-ZnO@ photoelectric-TiO2 core-shell nanofibers for dye decomposition.

    You, Huilin; Wu, Zheng; Jia, Yanmin; Xu, Xiaoli; Xia, Yuntao; Han, Zichen; Wang, Yu


    A mechano-/photo- bi-catalyst of piezoelectric-ZnO@photoelectric-TiO2 core-shell nanofibers was hydrothermally synthesized for Methyl Orange (10 mg L(-1)) decomposition. The mechano-/photo- bi-catalysis in ZnO@TiO2 is superior to mechano- or photo-catalysis in decomposing Methyl Orange, which is mainly attributed to the synergy effect of the piezoelectric-ZnO core's mechano-catalysis and the thin photoelectric TiO2 shell's photo-catalysis. The heterostructure of the piezoelectric-ZnO@photoelectric-TiO2 core-shell interface, being helpful to reduce electron-hole pair recombination and to separate the piezoelectrically-/photoelectric ally- induced electrons and holes, may also make a great contribution to the enhanced catalysis performance. The mechano-/photo-bi-catalysis in ZnO@TiO2 core-shell nanofibers possesses the advantages of high efficiency, non-toxicity and tractability and is potential in utilizing mechanical/solar energy to deal with dye wastewater. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Enhanced DSSCs efficiency via Cooperate co-absorbance (CdS QDs) and plasmonic core-shell nanoparticle (Ag@PVP)

    Amiri, Omid; Salavati-Niasari, Masoud; Bagheri, Samira; Yousefi, Amin Termeh


    This paper describes cooperate the co-absorbance (CdS QDs) and the plasmonic core-shell nanoparticles (Ag@PVP) of dye synthesized solar cells in which CdS QDs and Ag@PVP are incorporated into the TiO2 layer. Cooperative nanoparticles show superior behavior on enhancing light absorption in comparison with reference cells. Cooperated DSSC exhibits the best performance with the power conversion efficiency of 7.64% which is superior to that of the free–modified DSSC with the PCE of 5%. Detailed studies offer an effective approach to enhance the efficiency of dye synthesized solar cells.

  1. Simulation study of 3–5 keV x-ray conversion efficiency from Ar K-shell vs. Ag L-shell targets on the National Ignition Facility laser

    Kemp, G. E., E-mail:; Colvin, J. D.; Fournier, K. B.; May, M. J.; Barrios, M. A.; Patel, M. V.; Scott, H. A.; Marinak, M. M. [Lawrence Livermore National Laboratory, Livermore, California 94550-9698 (United States)


    Tailored, high-flux, multi-keV x-ray sources are desirable for studying x-ray interactions with matter for various civilian, space and military applications. For this study, we focus on designing an efficient laser-driven non-local thermodynamic equilibrium 3–5 keV x-ray source from photon-energy-matched Ar K-shell and Ag L-shell targets at sub-critical densities (∼n{sub c}/10) to ensure supersonic, volumetric laser heating with minimal losses to kinetic energy, thermal x rays and laser-plasma instabilities. Using HYDRA, a multi-dimensional, arbitrary Lagrangian-Eulerian, radiation-hydrodynamics code, we performed a parameter study by varying initial target density and laser parameters for each material using conditions readily achievable on the National Ignition Facility (NIF) laser. We employ a model, benchmarked against Kr data collected on the NIF, that uses flux-limited Lee-More thermal conductivity and multi-group implicit Monte-Carlo photonics with non-local thermodynamic equilibrium, detailed super-configuration accounting opacities from CRETIN, an atomic-kinetics code. While the highest power laser configurations produced the largest x-ray yields, we report that the peak simulated laser to 3–5 keV x-ray conversion efficiencies of 17.7% and 36.4% for Ar and Ag, respectively, occurred at lower powers between ∼100–150 TW. For identical initial target densities and laser illumination, the Ag L-shell is observed to have ≳10× higher emissivity per ion per deposited laser energy than the Ar K-shell. Although such low-density Ag targets have not yet been demonstrated, simulations of targets fabricated using atomic layer deposition of Ag on silica aerogels (∼20% by atomic fraction) suggest similar performance to atomically pure metal foams and that either fabrication technique may be worth pursuing for an efficient 3–5 keV x-ray source on NIF.

  2. Flow Characteristics Near to Stent Strut Configurations on Femoropopliteal Artery

    Paisal, Muhammad Sufyan Amir; Fadhil Syed Adnan, Syed; Taib, Ishkrizat; Ismail, Al Emran; Kamil Abdullah, Mohammad; Nordin, Normayati; Seri, Suzairin Md; Darlis, Nofrizalidris


    Femoropopiteal artery stenting is a common procedure suggested by medical expert especially for patient who is diagnosed with severe stenosis. Many researchers reported that the growth of stenosis is significantly related to the geometry of stent strut configuration. The different shapes of stent geometry are presenting the different flow pattern and re-circulation in stented femoropopliteal artery. The blood flow characteristics near to the stent geometry are predicted for the possibility of thrombosis and atherosclerosis to be formed as well as increase the growth of stenosis. Thus, this study aims to determine the flow characteristic near to stent strut configuration based on different hemodynamic parameters. Three dimensional models of stent and simplified femoropopliteal artery are modelled using computer aided design (CAD) software. Three different models of stent shapes; hexagon, circle and rectangle are simulated using computational fluid dynamic (CFD) method. Then, parametric study is implemented to predict the performance of stent due to hemodynamic differences. The hemodynamic parameters considered are pressure, velocity, low wall shear stress (WSSlow) and wall shear stress (WSS). From the observation, flow re-circulation has been formed for all simulated stent models which the proximal region shown the severe vortices. However, rectangular shape of stent strut (Type P3) shows the lowest WSSlow and the highest WSS between the range of 4 dyne/cm2 and 70 dyne/cm2. Stent Type P3 also shows the best hemodynamic stent performance as compare to others. In conclusion, Type P3 has a favourable result in hemodynamic stent performance that predicted less probability of thrombosis and atherosclerosis to be formed as well as reduces the growth of restenosis.

  3. Impact of structural properties on the internal quantum efficiency of InGaN - GaN core-shell nanorods

    Schimpke, Tilman [Osram Opto Semiconductors GmbH, Regensburg (Germany); Walter Schottky Institut, Technische Universitaet Muenchen, Garching (Germany); Mandl, Martin; Lugauer, Hans-Juergen; Strassburg, Martin [Osram Opto Semiconductors GmbH, Regensburg (Germany); Schuster, Fabian; Koblmueller, Gregor; Stutzmann, Martin [Walter Schottky Institut, Technische Universitaet Muenchen, Garching (Germany); Furthmeier, Stephan; Bougeard, Dominique; Reiger, Elisabeth; Korn, Tobias; Schueller, Christian [Institut fuer Exp. und Angew. Physik, Universitaet Regensburg (Germany)


    Core-shell III-nitride nanorods (NRs) have been proposed to solve a major issue in solid-state lighting, the so-called efficiency droop, by significantly increasing the active layer area scaling with the aspect ratio. However, the reported internal quantum efficiencies (IQE) in such core-shell structures are behind best planar LEDs. To study the processes limiting the IQE, position-controlled GaN/InGaN core-shell NRs were grown by MOVPE with diameters between 300 nm and 1.5 μm and aspect ratios of >5. The recombination processes in the InGaN quantum wells were investigated by temperature-dependent and time-resolved PL measurements. In addition, microscopic resolution was applied to correlate the structural properties obtained by SEM and Raman spectroscopy with optical properties. E.g., a double peak emission observed in micro-PL could be related to the semi-polar and non-polar facets of the InGaN quantum wells, respectively. The IQE values were deduced by temperature-dependent and time-resolved PL measurements.

  4. 利用Struts2框架和jQuery框架实现AJAX的开发%Implementation of the Development of AJAX Based on the Structure of Struts2 and jQuery



    Through asynchronous interaction technology, AJAX enchances the transmission efficiency and the speed of response between the server and the client side based on the B/S application. Introduces how to bring about the AJAX function based on Web applicatio%AJAX通过异步交互技术,提高在B/S模式下服务器与客户端之间的传输效率和响应速度。通过整合Struts2框架和jQuery框架,介绍如何实现Web应用程序下的NAx功能。

  5. Efficient Room-Temperature Methane Activation by the Closed-Shell, Metal-Free Cluster [OSiOH](+) : A Novel Mechanistic Variant.

    Sun, Xiaoyan; Zhou, Shaodong; Schlangen, Maria; Schwarz, Helmut


    The closed-shell cluster ion [OSiOH](+) is generated in the gas phase and its reactivity towards the thermal activation of CH4 has been examined using Fourier transform-ion cyclotron resonance (FT-ICR) mass spectrometry in conjunction with state-of-the-art quantum chemical calculations. Quite unexpectedly at room temperature, [OSiOH](+) efficiently mediates C-H bond activation, giving rise to [SiOH](+) and [SiOCH3 ](+) with the concomitant formation of methanol and water, respectively. Mechanistic aspects for this unprecedented reactivity pattern are presented, and the properties of the [OSiOH](+) /CH4 couple are compared with those of the closed-shell systems [OCOH](+) /CH4 and [MgOH](+) /CH4 ; the last two couples exhibit an entirely different reactivity scenario. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Effect of compressive force on aeroelastic stability of a strut-braced wing

    Sulaeman, Erwin


    Recent investigations of a strut-braced wing (SBW) aircraft show that, at high positive load factors, a large tensile force in the strut leads to a considerable compressive axial force in the inner wing, resulting in a reduced bending stiffness and even buckling of the wing. Studying the influence of this compressive force on the structural response of SBW is thus of paramount importance in the early stage of SBW design. The purpose of the this research is to investigate the effect of compressive force on aeroelastic stability of the SBW using efficient structural finite element and aerodynamic lifting surface methods. A procedure is developed to generate wing stiffness distribution for detailed and simplified wing models and to include the compressive force effect in the SBW aeroelastic analysis. A sensitivity study is performed to generate response surface equations for the wing flutter speed as functions of several design variables. These aeroelastic procedures and response surface equations provide a valuable tool and trend data to study the unconventional nature of SBW. In order to estimate the effect of the compressive force, the inner part of the wing structure is modeled as a beam-column. A structural finite element method is developed based on an analytical stiffness matrix formulation of a non-uniform beam element with arbitrary polynomial variations in the cross section. By using this formulation, the number of elements to model the wing structure can be reduced without degrading the accuracy. The unsteady aerodynamic prediction is based on a discrete element lifting surface method. The present formulation improves the accuracy of existing lifting surface methods by implementing a more rigorous treatment on the aerodynamic kernel integration. The singularity of the kernel function is isolated by implementing an exact expansion series to solve an incomplete cylindrical function problem. A hybrid doublet lattice/doublet point scheme is devised to reduce

  7. 78 FR 3356 - Airworthiness Directives; Various Aircraft Equipped With Wing Lift Struts


    ... Directives; Various Aircraft Equipped With Wing Lift Struts AGENCY: Federal Aviation Administration (FAA... airworthiness directive (AD) that applies to certain aircraft equipped with wing lift struts. The existing AD... Joint Aircraft System Component (JASC)/Air Transport Association (ATA) of America Code 57, Wings....

  8. 78 FR 79599 - Airworthiness Directives; Various Aircraft Equipped With Wing Lift Struts


    ... 99-01-05 R1] RIN 2120-AA64 Airworthiness Directives; Various Aircraft Equipped With Wing Lift Struts... aircraft equipped with wing lift struts. The list of affected airplanes in the Applicability section is incorrect. Several Piper Aircraft, Inc. Model PA-18 airplanes were inadvertently omitted from the final...

  9. 78 FR 73997 - Airworthiness Directives; Various Aircraft Equipped with Wing Lift Struts


    .... SUMMARY: We are revising Airworthiness Directive (AD) 99-01-05 for certain aircraft equipped with wing... unseal a sealed wing lift strut should be coordinated with the Atlanta Aircraft Certification Office (ACO...)(2) of this AD that occurs later, remove the wing lift struts following Piper Aircraft...

  10. Intrapericardial migration of dislodged sternal struts as late complication of open pectus excavatum repairs

    Haverich Axel


    Full Text Available Abstract We present a case of sternal steel strut dislodgement and migration in a patient undergoing Ravitch repair for pectus excavatum (PE 37 years ago. Broken struts perforated the right ventricle and right ventricular outflow tract (RVOT and additionally migrated into the left upper lobar bronchus. Dislodged sternal struts represent rare complications after surgical repair of patients suffering from pectus excavatum. Reviewing the literature, only five cases of intrapericardial migration of dislodged sternal struts or wires have been reported so far. In our case, the first strut was removed from the airways through a left antero-lateral thoracotomy. Using cardiopulmonary bypass, a second strut was removed via ventriculotomy. These life-threatening sequelae underscore the importance of postoperative follow-up and early removal of osteosynthetic materials used in open PE repair. Accurate preoperative localization of migrated materials and availability of CPB support are crucial for successful surgical removal. Introduction The migration of dislodged sternal steel struts or wires into the pericardium and cardiac cavities is a rare but life-threatening complication of open pectus excavatum (PE repair 1. Removal of these materials poses a challenge for cardiothoracic surgeons. Herein, the authors report a case of migration of dislodged steel struts through the right ventricle and right ventricular outflow tract (RVOT into the left upper lobar bronchus in a patient who underwent Ravitch repair 37 years ago.

  11. Strut thickness effect on restenosis of Multi-Link and Tri-Star stenting

    Honin Kanaya


    @@ Background Increased thrombegenicity and smooth muscle cell proliferative response induced by the metal struts compromise the advantages of coronary stenting. Adnan Kastrati et al. reported in the ISAR-STEREO trial that a reduced strut thickness of coronary stent is associated with improved follow up angiographic and clincal results.

  12. Tip Graft and Columellar Strut Using Dorsal Osseocartilaginous Hump

    Mehdi Bakhshaee


    Full Text Available Background: Although, different grafts are used for nasal tipplasty in cases with under projected or ill defined tip, the selectionof a graft material, which provides sufficient amount oftissue with least donor site morbidity and low recipient sitecomplication is challenging. The objectives of the presentstudy were to examine the usefulness of cartilaginous dorsumas a proper material for tip graft, and to introduce the cartilaginousdorsum as an acceptable material for columellar strut.Methods: Fifty six (18 males and 38 females patients wereoperated for augmentation tip plasty and hump reduction from2004 to 2008. The tailored cartilaginous or ostecartilaginousdorsum was used as a tip graft or columellar strut in 35 and 21cases, respectively. The cartilaginous framework was exposedusing open or close rhinoplasty approach in 41 and 15 cases,respectively. The patients were followed for 12- 36 months.Cosmetic outcomes and patients' satisfaction were obtainedusing qualitative measures.Results: The percentage of patients with very improved, improved,unchanged or unacceptable aesthetic outcome were39.29%, 50%, 3.57% and 7.14%, respectively. Moreover, thepercentages of very satisfied, satisfied, indifferent and unsatisfiedpatients were 66%, 18%, 9%, and 7%, respectively.Conclusion: The procedure provides a well-defined nasal tipwith no evidence of bifidity, angularity, or cartilage graft visibilityand displacement. The use of dorsal osteocartilaginousgraft offers outstanding advantages including ease of harvest,mould, fix, and low resorption.

  13. Mechanical behavior of a shelter system based on cable-strut structures

    Jian-guo CAI; Ya ZHOU; Jian FENG; Yi-xiang XU


    A shelter system based on cable-strut structures,consisting of compressive struts and high-tensile elements,is described in this paper.The deployment of the shelter is achieved by tightening inclined cables.Lower cables are used to terminate the deployment.The state of self-stress of the cable-strut structures in the fully deployed configuration is given,and the minimum strut length and the maximum load design of the shelter are discussed.The mechanical behavior of the system was studied under symmetrical and asymmetrical load cases.The results show that the shelter in the deployed configuration satisfies the ultimate limit and the serviceability limit state conditions.Finally,the stability of the cable-strut system is investigated,considering the effect of imperfections on the buckling of the shelter.We conclude that the influence of imperfections based on the consistent imperfection mode method is not significant.

  14. Influence of strut cross-section of stents on local hemodynamics in stented arteries

    Jiang, Yongfei; Zhang, Jun; Zhao, Wanhua


    Stenting is a very effective treatment for stenotic vascular diseases, but vascular geometries altered by stent implantation may lead to flow disturbances which play an important role in the initiation and progression of restenosis, especially in the near wall in stented arterial regions. So stent designs have become one of the indispensable factors needed to be considered for reducing the flow disturbances. In this paper, the structural designs of strut cross-section are considered as an aspect of stent designs to be studied in details. Six virtual stents with different strut cross-section are designed for deployments in the same ideal arterial model. Computational fluid dynamics (CFD) methods are performed to study how the shape and the aspect ratio (AR) of strut cross-section modified the local hemodynamics in the stented segments. The results indicate that stents with different strut cross-sections have different influence on the hemodynamics. Stents with streamlined cross-sectional struts for circular arc or elliptical arc can significantly enhance wall shear stress (WSS) in the stented segments, and reduce the flow disturbances around stent struts. The performances of stents with streamlined cross-sectional struts are better than that of stents with non-streamlined cross-sectional struts for rectangle. The results also show that stents with a larger AR cross-section are more conductive to improve the blood flow. The present study provides an understanding of the flow physics in the vicinity of stent struts and indicates that the shape and AR of strut cross-section ought to be considered as important factors to minimize flow disturbance in stent designs.

  15. Nanosized yolk-shell Fe3O4@Zr(OH)x spheres for efficient removal of Pb(II) from aqueous solution.

    Pan, Shunlong; Li, Jiansheng; Wan, Gaojie; Liu, Chao; Fan, Wenhong; Wang, Lianjun


    In this work, Fe3O4@Zr(OH)x yolk-shell nanospheres (YSNs) were synthesized via a two-step process and further examined as adsorbents for the removal of Pb(II). To understand the hollow structure on the adsorption properties of Pb(II), another adsorbent without hollow cavities, i.e., Fe3O4@SiO2@Zr(OH)x core-shell nanospheres (CSNs), was also prepared for comparison. The adsorption results showed that Fe3O4@Zr(OH)x YSNs exhibited 41.6% higher Pb(II) adsorption capacity as compared to that of Fe3O4@SiO2@Zr(OH)x CSNs. The isotherm was well fitted to Langmuir adsorption model with qmax value of 310.8 mg/g after normalized by the weight of Zr in Fe3O4@Zr(OH)x YSNs. Scanning transmission electron microscopy (STEM) mapping results revealed that the existence of cavities between Fe3O4 cores and Zr(OH)x shells is responsible for the improved adsorption performance. XPS analysis indicated the surface hydroxyl groups played a key role in the Pb(II) adsorption. The removal efficiency of Pb(II) was maintained above 90% in five consecutive adsorption-desorption cycles.

  16. Dye-sensitized Pt@TiO2 core–shell nanostructures for the efficient photocatalytic generation of hydrogen

    Jun Fang


    Full Text Available Pt@TiO2 core–shell nanostructures were prepared through a hydrothermal method. The dye-sensitization of these Pt@TiO2 core–shell structures allows for a high photocatalytic activity for the generation of hydrogen from proton reduction under visible-light irradiation. When the dyes and TiO2 were co-excited through the combination of two irradiation beams with different wavelengths, a synergic effect was observed, which led to a greatly enhanced H2 generation yield. This is attributed to the rational spatial distribution of the three components (dye, TiO2, Pt, and the vectored transport of photogenerated electrons from the dye to the Pt particles via the TiO2 particle bridge.

  17. The important role of surface ligand on CdSe/CdS core/shell nanocrystals in affecting the efficiency of H2 photogeneration from water

    Wang, Ping; Zhang, Jie; He, Haili; Xu, Xiaolong; Jin, Yongdong


    The use of colloidal semiconductor nanocrystals (NCs), especially those with a core/shell structure, for photocatalytic hydrogen (H2) production from water is currently one of the hottest research fields. Although the ligand on the semiconductor NC surface is crucial to the optical and optoelectronic properties of the NC, the study of the ligand effect on the photocatalytic activity of H2 generation is rarely reported. Herein, we employ nearly monodispersed CdSe/CdS core/shell NCs as a model photocatalytic system, and three kinds of ligands with different numbers of functional thiol groups (i.e., poly(acrylic acid), 3-mercaptopropionic acid and 2,3-dimercaptosuccinic acid) are selected as the ligands to investigate the effect of ligand on the efficiency of H2 photogeneration. The results show that the H2 photogeneration efficiency is highly dependent on the surface ligand of the NCs, and it increases with the increase of the number of the functional thiol groups in the ligand, and correspondingly, the photoluminescence intensity and average fluorescence lifetime, which are measured by steady state and time-resolved fluorescence measurements, are decreased. The surface trap-related charge separation efficiency, which is mediated by surface coating with different ligands, is supposed to cause the distinct ligand-dependent performance in the H2 evolution.The use of colloidal semiconductor nanocrystals (NCs), especially those with a core/shell structure, for photocatalytic hydrogen (H2) production from water is currently one of the hottest research fields. Although the ligand on the semiconductor NC surface is crucial to the optical and optoelectronic properties of the NC, the study of the ligand effect on the photocatalytic activity of H2 generation is rarely reported. Herein, we employ nearly monodispersed CdSe/CdS core/shell NCs as a model photocatalytic system, and three kinds of ligands with different numbers of functional thiol groups (i.e., poly(acrylic acid), 3

  18. Effects of nozzle-strut integrated design concepton on the subsonic turbine stage flowfield

    Liu, Jun; Du, Qiang; Liu, Guang; Wang, Pei; Zhu, Junqiang


    In order to shorten aero-engine axial length, substituting the traditional long chord thick strut design accompanied with the traditional low pressure(LP) stage nozzle, LP turbine is integrated with intermediate turbine duct (ITD). In the current paper, five vanes of the first stage LP turbine nozzle is replaced with loaded struts for supporting the engine shaft, and providing oil pipes circumferentially which fulfilled the areo-engine structure requirement. However, their bulky geometric size represents a more effective obstacle to flow from high pressure (HP) turbine rotor. These five struts give obvious influence for not only the LP turbine nozzle but also the flowfield within the ITD, and hence cause higher loss. Numerical investigation has been undertaken to observe the influence of the Nozzle-Strut integrated design concept on the flowfield within the ITD and the nearby nozzle blades. According to the computational results, three main conclusions are finally obtained. Firstly, a noticeable low speed area is formed near the strut's leading edge, which is no doubt caused by the potential flow effects. Secondly, more severe radial migration of boundary layer flow adjacent to the strut's pressure side have been found near the nozzle's trailing edge. Such boundary layer migration is obvious, especially close to the shroud domain. Meanwhile, radial pressure gradient aggravates this phenomenon. Thirdly, velocity distribution along the strut's pressure side on nozzle's suction surface differs, which means loading variation of the nozzle. And it will no doubt cause nonuniform flowfield faced by the downstream rotor blade.

  19. Application of linear and non-linear methods for modeling removal efficiency of textile dyes from aqueous solutions using magnetic Fe3O4 impregnated onto walnut shell

    Ashrafi, Motahare; Arab Chamjangali, Mansour; Bagherian, Ghadamali; Goudarzi, Nasser


    The performance of the Nano-magnetite Fe3O4 impregnated onto walnut shell (Fe3O4-WNS), which possessed the adsorption features of walnut shell and the magnetic property of Fe3O4, was investigated for the elimination of the methyl violet and Rhodamine 6G from contaminated aqueous solutions. The effects of different experimental variables on the removal efficiency of the cited dyes were examined. Then these variables were used as the inputs to generate linear and non-linear models such as the multiple linear regression, random forest, and artificial neural network to predict the removal efficiency of these dye species at different experimental conditions. The validation studies of these models were performed using the test set, which was not present in the modeling procedure. It was found that ANN had a higher ability to predict the adsorption process under different experimental conditions, and could be applied for the development of an automated dye wastewater removal plant. Also the maximum adsorption capacity (qmax) indicated that the qmax value for Fe3O4-WNS for removal of cationic dyes was comparable or better than that for some reported adsorbents. Also it should be cited that exhausted Fe3O4-WNS was regenerated using dishwashing liquid, and reused for removal of the cited dye species from aqueous solutions.

  20. Engineering of Radioiodine-Labeled Gold Core-Shell Nanoparticles As Efficient Nuclear Medicine Imaging Agents for Trafficking of Dendritic Cells.

    Lee, Sang Bong; Lee, Sang-Woo; Jeong, Shin Young; Yoon, GhilSuk; Cho, Sung Jin; Kim, Sang Kyoon; Lee, In-Kyu; Ahn, Byeong-Cheol; Lee, Jaetae; Jeon, Yong Hyun


    The development of highly sensitive, stable, and biocompatible imaging agents allowing visualization of dendritic cell (DC) migration is one of the essential factors for effective DC-based immunotherapy. Here, we used a novel and efficient synthesis approach to develop radioiodine-124-labeled tannic acid gold core-shell nanoparticles ((124)I-TA-Au@AuNPs) for DC labeling and in vivo tracking of their migration using positron emission tomography (PET). (124)I-TA-Au@AuNPs were produced within 40 min in high yield via straightforward tannic acid-mediated radiolabeling chemistry and incorporation of Au shell, which resulted in high radio-sensitivity and excellent chemical stability of nanoparticles in DCs and living mice. (124)I-TA-Au@AuNPs demonstrated good DC labeling efficiency and did not affect cell biological functions, including proliferation and phenotype marker expression. Importantly, (124)I-TA-Au@AuNPs in an extremely low amount (0.1 mg/kg) were successfully applied to track the migration of DCs to lymphoid organs (draining lymph nodes) in mice.

  1. A non-covalent "click chemistry" strategy to efficiently coat highly porous MOF nanoparticles with a stable polymeric shell.

    Aykaç, Ahmet; Noiray, Magali; Malanga, Milo; Agostoni, Valentina; Casas-Solvas, Juan Manuel; Fenyvesi, Éva; Gref, Ruxandra; Vargas-Berenguel, Antonio


    Metal-organic framework nanoparticles (nanoMOFs) are biodegradable highly porous materials with a remarkable ability to load therapeutic agents with a wide range of physico-chemical properties. Engineering the nanoMOFs surface may provide nanoparticles with higher stability, controlled release, and targeting abilities. Designing postsynthetic, non-covalent self-assembling shells for nanoMOFs is especially appealing due to their simplicity, versatility, absence of toxic byproducts and minimum impact on the original host-guest ability. In this study, several β-cyclodextrin-based monomers and polymers appended with mannose or rhodamine were randomly phosphorylated, and tested as self-assembling coating building blocks for iron trimesate MIL-100(Fe) nanoMOFs. The shell formation and stability were studied by isothermal titration calorimetry (ITC), spectrofluorometry and confocal imaging. The effect of the coating on tritium-labeled AZT-PT drug release was estimated by scintillation counting. Shell formation was conveniently achieved by soaking the nanoparticles in self-assembling agent aqueous solutions. The grafted phosphate moieties enabled a firm anchorage of the coating to the nanoMOFs. Coating stability was directly related to the density of grafted phosphate groups, and did not alter nanoMOFs morphology or drug release kinetics. An easy, fast and reproducible non-covalent functionalization of MIL-100(Fe) nanoMOFs surface based on the interaction between phosphate groups appended to β-cyclodextrin derivatives and iron(III) atoms is presented. This study proved that discrete and polymeric phosphate β-cyclodextrin derivatives can conform non-covalent shells on iron(III)-based nanoMOFs. The flexibility of the β-cyclodextrin to be decorated with different motifs open the way towards nanoMOFs modifications for drug delivery, catalysis, separation, imaging and sensing. This article is part of a Special Issue entitled "Recent Advances in Bionanomaterials" Guest

  2. 一种struts2整合hibernate的方案



    Hibernate是一个非常优秀的ORM框架,允许开发人员使用面向对象的方式进行教据库访问.Struts2是JAVA EE应用的MVC层解决方案,主要提供系统的控制器支持.文章介绍了Hilbernate框架与struts2的概念、作用,提出了一种Struts2整合Hibernate的方案.

  3. Optical antenna gain. III - The effect of secondary element support struts on transmitter gain

    Klein, B. J.; Degnan, J. J.


    The effect of a secondary-element spider support structure on optical antenna transmitter gain is analyzed. An expression describing the influence of the struts on the axial gain, in both the near and far fields, is derived as a function of the number of struts and their width. It is found that, for typical systems, the struts degrade the on-axis gain by less than 0.4 dB, and the first side-lobe level is not increased significantly. Contour plots have also been included to show the symmetry of the far-field distributions for three- and four-support members.

  4. Optical antenna gain. 3: The effect of secondary element support struts on transmitter gain.

    Klein, B J; Degnan, J J


    The effect of a secondary element spider support structure on optical antenna transmitter gain is analyzed. An expression describing the influence of the struts on the axial gain, in both the near and far fields, is derived as a function of the number of struts and their width. It is found that, for typical systems, the struts degrade the on-axis gain by less than 0.4 dB, and the first side-lobe level is not increased significantly. Contour plots have also been included to show the symmetry of the far-field distributions for three and four support members.

  5. Fabrication of hierarchical core-shell polydopamine@MgAl-LDHs composites for the efficient enrichment of radionuclides

    Zhu, Kairuo; Lu, Songhua; Gao, Yang; Zhang, Rui; Tan, Xiaoli; Chen, Changlun


    Novel hierarchical core/shell structured polydopamine@MgAl-layered double hydroxides (PDA@MgAl-LDHs) composites involving MgAl-layered double hydroxide shells and PDA cores were fabricated thought one-pot coprecipitation assembly and methodically characterized by X-ray diffraction, Fourier transformed infrared spectroscopy, scanning/transmission electron microscopy, selected area electron diffraction, elemental mapping, thermogravimetric analysis and X-ray photoelectron spectroscopy technologies. U(VI) and Eu(III) sorption experiments showed that the PDA@MgAl-LDHs exhibited higher sorption ability with a maximum sorption capacity of 142.86 and 76.02 mg/g at 298 K and pH 4.5, respectively. More importantly, according to XPS analyses, U(VI) and Eu(III) were sorbed on PDA@MgAl-LDHs via oxygen-containing functional groups, and the chemical affinity of U(VI) by oxygen-containing functional groups is higher than that of Eu(III). These observations show great expectations in the enrichment of radionuclides from aquatic environments by PDA@MgAl-LDHs.

  6. Ternary Nanoparticles with a Sheddable Shell Efficiently Deliver MicroRNA-34a against CD44-Positive Melanoma.

    Fan, Minmin; Zeng, Ye; Ruan, Huitong; Zhang, Zhirong; Gong, Tao; Sun, Xun


    PEGylation can stabilize drug delivery systems for cancer therapy by creating repulsive interactions with biological components in vivo. While these interactions reduce nonspecific adsorption of drug-loaded particles onto nontarget surfaces, they also inhibit internalization of particles into target cells. To circumvent this so-called "PEG-dilemma", we have developed nanoparticles with a PEG coating that is shed after arrival in target tissue. Positively charged polycation nanoparticles were assembled with microRNA-34a via electrostatic interactions and then coated again via electrostatic interactions with an anionic PEG derivative that separates from the nanoparticle in the acidic tumor microenvironment. The resulting ternary nanoparticles with a sheddable shell have nearly neutral surface charge, which markedly reduces nonspecific adsorption. Shedding the PEG coat enhanced nanoparticle uptake into CD44-positive melanoma cells and promoted microRNA-34a release, which down-regulated CD44 expression and thereby inhibited tumor growth. We conclude that nanocarriers with a sheddable shell show promise for cancer therapy.

  7. Efficient noble-metal-free γ-Fe₂O₃@NiO core-shell nanostructured photocatalysts for water oxidation.

    Du, Xiaoqiang; Wei, Jie; Zhao, Jinli; Han, Ruixin; Ding, Yong


    Flowerlike noble-metal-free γ-Fe2O3@NiO core-shell hierarchical nanostructures have been fabricated and examined as a catalyst in the photocatalytic oxidation of water with [Ru(bpy)3](ClO4)2 as a photosensitizer and Na2S2O8 as a sacrificial electron acceptor. An apparent TOF of 0.29 μmols(-1) m(-2) and oxygen yield of 51% were obtained with γ-Fe2O3@NiO. The γ-Fe2O3@NiO core-shell hierarchical nanostructures could be easily separated from the reaction solution whilst maintaining excellent water-oxidation activity in the fourth and fifth runs. The surface conditions of γ-Fe2O3@NiO also remained unchanged after the photocatalytic reaction, as confirmed by X-ray photoelectron spectroscopy (XPS). © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Ultrathin CoS2 shells anchored on Co3O4 nanoneedles for efficient hydrogen evolution electrocatalysis

    Li, Tongtong; Niu, Kaili; Yang, Minghe; Shrestha, Nabeen K.; Gao, Zhida; Song, Yan-Yan


    Designing new earth-abundant and low-cost catalysts toward the hydrogen evolution reaction (HER) plays a key role in realization of hydrogen economy. In this study, we demonstrate that excellent HER activity is achieved with core-shell Co3O4@CoS2 nanoneedle arrays synthesized by an instantaneous thermal treatment of nanoneedle precursor in H2S atmosphere. The Co3O4@CoS2 structures thus obtained exhibit the current density of 100 mA cm-2 at a remarkably small overpotential of 210 mV with a small Tafel slope of 45.8 mV decade-1 in an acidic medium. The outstanding HER performance is achieved particularly from the unique core-shell nanostructure which offers enough electric conductivity and abundant active sites at the grain boundaries and stacking misalignments between two neighbouring cobalt nanostructures. This instantaneous thermal treatment strategy is compatible with the traditional long-time sulfur vapor to prepare transition metal chalcogenides with significant hydrogen evolution reaction activities.

  9. Evaluation of Kerosene Fuelled Scramjet Combustor using a Combination of Cooled and Uncooled Struts

    C. Chandrasekhar


    Full Text Available The scramjet combustor a vital component of scramjet engine has been designed by employing fuel injection struts. Several experimental studies have been carried out to evaluate the propulsive performance and structural integrity of the in-stream fuel injection struts in the connect-pipe test facility. As the mission objective of hypersonic demonstrator is to flight test the scramjet engine for 20 s duration, in-stream fuel injection struts which are designed as heat sink devices encounter hostile flow field conditions especially in terms of high thermal and high convective loads in the scramjet combustor. To circumvent these adverse conditions, materials like Niobium C-103 and W-Ni-Fe alloys have been used for the construction of struts and a number of tests have been carried out to evaluate the survivability of the in-stream fuel injection struts in the scramjet combustor. The results thus obtained show that the erosion of leading edges of the Stage-II fuel injection struts in the initial phase and subsequently puncturing of the fuel injection manifold after 10-12 s of the test are noticed, while the other stages of the struts are found to be intact. This deteriorating leading edges of Stage-II struts with respect to time, affect the overall propulsive performance of the combustor. To mitigate this situation, Stage-II struts have been designed as cooled structure and other Stages of struts are designed as un-cooled structure. Material of construction of struts used is Nimonic C-263 alloy. This paper highlights the results of the static test of the scramjet combustor, which has been carried out at a combustor entry Mach number of 2.0, total temperature of 2000 K, with an overall kerosene fuel equivalence ratio of 1.0 and for the supersonic combustion duration of 20 s. Low back pressure has been created at the exit of the scramjet combustor using ejector system to avoid flow separation.Visual inspection of the fuel injection struts after the test

  10. Highly efficient anode catalyst with a Ni@PdPt core–shell nanostructure for methanol electrooxidation in alkaline media

    Pei-shu Yu; Chun-tao Liu; Bo Feng; Jia-feng Wan; Li Li; Chun-yu Du


    To enhance the electrocatalytic activity of anode catalysts used in alkaline-media direct methanol fuel cells (DMFCs), a Ni@PdPt electrocatalyst was successfully prepared using a three-phase-transfer method. The Ni@PdPt electrocatalyst was characterized by X-ray dif-fraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), and high-resolution TEM (HRTEM) techniques. The experimental results indicate that the average particle size of the core–shell-structured Ni@PdPt electrocatalyst is approxi-mately 5.6 nm. The Ni@PdPt electrocatalyst exhibits a catalytic activity 3.36 times greater than that of PdPt alloys for methanol oxidation in alkaline media. The developed Ni@PdPt electrocatalyst offers a promising alternative as a highly electrocatalytically active anode catalyst for alkaline DMFCs.

  11. The strut-and-tie models in reinforced concrete structures analysed by a numerical technique

    V. S. Almeida

    Full Text Available The strut-and-tie models are appropriate to design and to detail certain types of structural elements in reinforced concrete and in regions of stress concentrations, called "D" regions. This is a good model representation of the structural behavior and mechanism. The numerical techniques presented herein are used to identify stress regions which represent the strut-and-tie elements and to quantify their respective efforts. Elastic linear plane problems are analyzed using strut-and-tie models by coupling the classical evolutionary structural optimization, ESO, and a new variant called SESO - Smoothing ESO, for finite element formulation. The SESO method is based on the procedure of gradual reduction of stiffness contribution of the inefficient elements at lower stress until it no longer has any influence. Optimal topologies of strut-and-tie models are presented in several instances with good settings comparing with other pioneer works allowing the design of reinforcement for structural elements.

  12. Highly efficient, long life, reusable and robust photosynthetic hybrid core-shell beads for the sustainable production of high value compounds.

    Desmet, Jonathan; Meunier, Christophe; Danloy, Emeric; Duprez, Marie-Eve; Lox, Frédéric; Thomas, Diane; Hantson, Anne-Lise; Crine, Michel; Toye, Dominique; Rooke, Joanna; Su, Bao-Lian


    An efficient one-step process to synthesize highly porous (Ca-alginate-SiO2-polycation) shell: (Na-alginate-SiO2) core hybrid beads for cell encapsulation, yielding a reusable long-life photosynthetically active material for a sustainable manufacture of high-value metabolites is presented. Bead formation is based on crosslinking of an alginate biopolymer and mineralisation of silicic acid in combination with a coacervation process between a polycation and the silica sol, forming a semi-permeable external membrane. The excellent mechanical strength and durability of the monodispersed beads and the control of their porosity and textural properties is achieved by tailoring the silica and alginate loading, polycation concentration and incubation time during coacervation. This process has led to the formation of a remarkably robust hybrid material that confers exceptional protection to live cells against sheer stresses and contamination in a diverse range of applications. Dunaliella tertiolecta encapsulated within this hybrid core-shell system display high photosynthetic activity over a long duration (>1 year). This sustainable biotechnology could find use in high value chemical harvests and biofuel cells to photosynthetic solar cells (energy transformation, electricity production, water splitting technologies). Furthermore the material can be engineered into various forms from spheres to variable thickness films, broadening its potential applications. Copyright © 2015 Elsevier Inc. All rights reserved.

  13. Fabrication of Au@Ag core/shell nanoparticles decorated TiO2 hollow structure for efficient light-harvesting in dye-sensitized solar cells.

    Yun, Juyoung; Hwang, Sun Hye; Jang, Jyongsik


    Improving the light-harvesting properties of photoanodes is promising way to enhance the power conversion efficiency (PCE) of dye-sensitized solar cells (DSSCs). We synthesized Au@Ag core/shell nanoparticles decorated TiO2 hollow nanoparticles (Au@Ag/TiO2 HNPs) via sol-gel reaction and chemical deposition. The Au@Ag/TiO2 HNPs exhibited multifunctions from Au@Ag core/shell NPs (Au@Ag CSNPs) and TiO2 hollow nanoparticles (TiO2 HNPs). These Au@Ag CSNPs exhibited strong and broadened localized surface plasmon resonance (LSPR), together with a large specific surface area of 129 m(2) g(-1), light scattering effect, and facile oxidation-reduction reaction of electrolyte from TiO2 HNPs, which resulted in enhancement of the light harvesting. The optimum PCE of η = 9.7% was achieved for the DSSCs using photoanode materials based on TiO2 HNPs containing Au@Ag/TiO2 HNPs (0.2 wt % Au@Ag CSNPs with respect to TiO2 HNPs), which outperformed by 24% enhancement that of conventional photoanodes formed using P25 (η = 7.8%).

  14. Geometry of Prismatic Tensegrity Constructions Composed of Three and Four-strut Cells

    Olejníková Tatiana


    Full Text Available In the paper there is described geometry of double layer tensegrity constructions composed of prismatic cells with rhombic configuration of three or four strut bases so-called prismatic Tensegrity constructions. There are described bi-dimensional assemblies creating double layer grids of three or four-strut cells with a node-on-node junction. The grids can be planar, of one or two curvature constructions.

  15. The medical orbital strut in the prevention of postdecompression dystopia in dysthyroid ophthalmopathy.

    Goldberg, R A; Shorr, N; Cohen, M S


    Ocular dystopia with inferomedial displacement of the globe is an unusual but well-recognized complication of bony orbital decompression. It is caused by displacement of the muscle cone and orbital connective tissue system into the maxillary and ethmoidal sinuses. We illustrate a surgical variation of bony orbital decompression leaving intact a strut of bone at the maxillary-ethmoid junction. This bony strut reduces inferomedial displacement of the muscle cone and provides a medial supporting "ledge" in cases requiring late orbital reconstruction.

  16. Strut Supported Bell XS-2 in 7 x 10 Foot Tunnel


    The strut system used conventionally into the 1940s to support models in large wind tunnels disturbed airflow so much that many test results were questionable, especially at higher Mach numbers. In this photo from August 1946, a strut-supported model of the Bell XS-2 is being tested in the 7x10 Foot Tunnel. Photograph published in Engineer in Charge: A History of the Langley Aeronautical Laboratory, 1917-1958 by James R. Hansen. Page 313.

  17. One-step synthesis of magnetite core/zirconia shell nanocomposite for high efficiency removal of phosphate from water

    Wang, Zhe; Xing, Mingchao; Fang, Wenkan; Wu, Deyi, E-mail:


    Graphical abstract: - Highlights: • Magnetite core/zirconia shell nanocomposite was prepared by one-step method. • Fe/Zr molar ratio of 4/1 allowed high magnetization and high adsorption capacity. • The nanocomposite had good selectivity towards phosphate. • Ligand exchange was the adsorption mechanism of phosphate. • Desorption of adsorbed phosphate could be achieved by NaOH treatment. - Abstract: A self-assembled magnetite core/zirconia shell (Fe{sub 3}O{sub 4}@ZrO{sub 2}) nanoparticle material was fabricated by the one-step co-precipitation method to capture phosphate from water. Fe{sub 3}O{sub 4}@ZrO{sub 2} with different Fe/Zr molar ratios were obtained and characterized by XRD, TEM, BET surface area and magnetization. It was shown that, with the decreasing of Fe/Zr molar ratio, magnetization decreased whereas surface area and adsorption capacity of phosphate increased. Fe{sub 3}O{sub 4}@ZrO{sub 2} with the ratio of higher than 4:1 had satisfactory magnetization property (>23.65 emu/g), enabling rapid magnetic separation from water and recycle of the spent adsorbent. The Langmuir adsorption capacity of Fe{sub 3}O{sub 4}@ZrO{sub 2} reached 27.93–69.44 mg/g, and the adsorption was fast (90% of phosphate removal within 20 min). The adsorption decreases with increasing pH, and higher ionic strength caused slight increase in adsorption at pH > about 5.5. The presence of chloride, nitrate and sulfate anions did not bring about significant changes in adsorption. As a result, Fe{sub 3}O{sub 4}@ZrO{sub 2} performed well to remove phosphate from real wastewater. These results were interpreted by the ligand exchange mechanism, i.e., the direct coordination of phosphate onto zirconium by replacement of hydroxyl groups. Results suggested that phosphate reacted mainly with surface hydroxyl groups but diffusion into interior of zirconia phase also contributed to adsorption. The adsorbed phosphate could be desorbed with a NaOH treatment and the regenerated Fe

  18. 基于Struts2框架的网站信息内容管理平台的设计与实现%Design and Implementation of Website Content Management System Based on Struts2



    Struts2是一个可扩展的Java EE Web框架,它继承Struts1和WebWork两个框架的优点,该框架主要负责Web页面端的控制,并将页面层与业务层分离.本文在对Struts2框架研究的基础上,阐述该框架在网站信息内容管理系统开发中的具体应用.%Struts2 is an extendable Java EE Web framework. It inherits the advantages of Struts 1 and Web Work. Struts2 is re-sponsible for the control of Web pages and separates the page layer and the business layer. Based on the research on Stnits2 tech-nology, this paper describes the design and implementation of website content management system by struts2 framework.

  19. C@SiNW/TiO2 core-shell nanoarrays with sandwiched carbon passivation layer as high efficiency photoelectrode for water splitting.

    Devarapalli, Rami Reddy; Debgupta, Joyashish; Pillai, Vijayamohanan K; Shelke, Manjusha V


    One-dimensional heterostructure nanoarrays are efficiently promising as high performance electrodes for photo electrochemical (PEC) water splitting applications, wherein it is highly desirable for the electrode to have a broad light absorption, efficient charge separation and redox properties as well as defect free surface with high area suitable for fast interfacial charge transfer. We present highly active and unique photoelectrode for solar H2 production, consisting of silicon nanowires (SiNWs)/TiO2 core-shell structures. SiNWs are passivated to reduce defect sites and protected against oxidation in air or water by forming very thin carbon layer sandwiched between SiNW and TiO2 surfaces. This carbon layer decreases recombination rates and also enhances the interfacial charge transfer between the silicon and TiO2. A systematic investigation of the role of SiNW length and TiO2 thickness on photocurrent reveals enhanced photocurrent density up to 5.97 mA/cm(2) at 1.0 V vs.NHE by using C@SiNW/TiO2 nanoarrays with photo electrochemical efficiency of 1.17%.

  20. One-step synthesis of magnetite core/zirconia shell nanocomposite for high efficiency removal of phosphate from water

    Wang, Zhe; Xing, Mingchao; Fang, Wenkan; Wu, Deyi


    A self-assembled magnetite core/zirconia shell (Fe3O4@ZrO2) nanoparticle material was fabricated by the one-step co-precipitation method to capture phosphate from water. Fe3O4@ZrO2 with different Fe/Zr molar ratios were obtained and characterized by XRD, TEM, BET surface area and magnetization. It was shown that, with the decreasing of Fe/Zr molar ratio, magnetization decreased whereas surface area and adsorption capacity of phosphate increased. Fe3O4@ZrO2 with the ratio of higher than 4:1 had satisfactory magnetization property (>23.65 emu/g), enabling rapid magnetic separation from water and recycle of the spent adsorbent. The Langmuir adsorption capacity of Fe3O4@ZrO2 reached 27.93-69.44 mg/g, and the adsorption was fast (90% of phosphate removal within 20 min). The adsorption decreases with increasing pH, and higher ionic strength caused slight increase in adsorption at pH > about 5.5. The presence of chloride, nitrate and sulfate anions did not bring about significant changes in adsorption. As a result, Fe3O4@ZrO2 performed well to remove phosphate from real wastewater. These results were interpreted by the ligand exchange mechanism, i.e., the direct coordination of phosphate onto zirconium by replacement of hydroxyl groups. Results suggested that phosphate reacted mainly with surface hydroxyl groups but diffusion into interior of zirconia phase also contributed to adsorption. The adsorbed phosphate could be desorbed with a NaOH treatment and the regenerated Fe3O4@ZrO2 could be repeatedly used.

  1. Design aids for stiffened composite shells with cutouts

    Sahoo, Sarmila


    This book focuses on the free vibrations of graphite-epoxy laminated composite stiffened shells with cutout both in terms of the natural frequencies and mode shapes. The dynamic analysis of shell structures, which may have complex geometry and arbitrary loading and boundary conditions, is solved efficiently by the finite element method, even including cutouts in shells. The results may be readily used by practicing engineers dealing with stiffened composite shells with cutouts. Several shell forms viz. cylindrical shell, hypar shell, conoidal shell, spherical shell, saddle shell, hyperbolic paraboloidal shell and elliptic paraboloidal shell are considered in the book. The dynamic characteristics of stiffened composite shells with cutout are described in terms of the natural frequency and mode shapes. The size of the cutouts and their positions with respect to the shell centre are varied for different edge constraints of cross-ply and angle-ply laminated composite shells. The effects of these parametric variat...

  2. One-pot aqueous-phase synthesis of ultra-small CdSe/CdS/CdZnS core-shell-shell quantum dots with high-luminescent efficiency and good stability

    Zhan Hongju; Zhou Peijiang, E-mail:; Pan Keliang; He Ting; He Xuan; Zhou Chuanyun; He Yuning [Wuhan University, School of Resource and Environmental Science, Hubei Biomass-Resource Chemistry and Environmental Biotechnology Key Laboratory (China)


    We describe the preparation and structural characterization of ultra-small water-dispersible CdSe semiconductor nanocrystal quantum dots (QDs), which are covered by a double-shell structure from CdS and CdZnS through a one-pot microwave-assisted synthesis technique. Because of the radial increase of the respective valence- and conduction-band offsets, the resulting core-shell-shell CdSe/CdS/CdZnS QDs are well electronically passivated, which endows them with high-fluorescence quantum yield of 90 % and high crystallinity, as was investigated by optical characterization, X-ray diffraction, high-resolution transmission electron microscopy, and X-ray photoelectron spectroscopy. Also, due to the stepwise adjustment of the lattice parameters in the radial direction, the obtained QDs display remarkable photostability, acid stability, and oxidation stability both in the aqueous solutions and the intracellular environment. The cytotoxicity experiment further substantiates the good biocompatibility of the core-shell-shell particles, though the size of the obtained QDs was very small (about 3.2 nm). This implied that the CdSe/CdS/CdZnS core-shell-shell QDs can be used as a promising candidate for fluorescent QDs-based biological applications.


    CHEN Xin; YAO Yan; LU Chuan-jing; CHEN Ying; CAOJia-yi


    To apply the measurements of model experiment in water tunnel to the actual sailing condition,it is necessary to know accurately the strut effect and its rule.In the present work,the corresponding interferences of one-side strut and two-side strut on the natural cavitating flows around a submerged vehicle in water tunnel were investigated numerically,using the homogeneous equilibrium two-phase model coupled with a natural cavitation model.The numerical simulation results show that the strut types have distinct effects on the hydrodynamic properties.For the same given upstream velocity and downstream pressure,the existence of the strut leads to an increment of natural cavitation number,reduces the low-pressure region and depresses the pressure on the vehicle surface near the sides of strut.In the case of given cavitaiton number,the influences of the two-side strut on the drag and lift coefficients are both enhanced along with the increment of attack angle,however the influence of the one-side strut gradually gets stronger on the drag coefficient but weaker on the lift coefficient contrarily.In addition,based on the present numerical results,a correction method by introducing the sigmoidal logistic function is proposed to eliminate the interference from the foil-shaped strut.

  4. Cell Area and Strut Distribution Changes of Bent Coronary Stents: A Finite Element Analysis

    ZHAO Yang; WU Wei; YANG Da-zhi; QI Min


    Coronary stents are metal coils or mesh tubes delivered to blocked vessels through catheters, which are expanded by balloons to reopen and scaffold target vessels. Recently,special drugs are carried by stents (drug-eluting stents) to further reduce in-stent restenosis rate after stenting procedure. However,continual study on biomechanical characteristics of stents is necessary for better interactions between stents and tissue, or to provide a more suitable drug loading platform for drug-eluting stents. The purpose of this paper is to show how finite element methods can be used to study cell area and strut distribution changes of bent coronary stents. A same bending deformation was applied to two commercial coronary stent models by a rigid curved vessel. Results show that the stent design influenced the changes of cell area and strut distribution under bending situation. The stent with links had more cell area changes at outer curvature, and the stent with peak-peak (><) strut design could have strut contact and overlapping at inner curvature. In conclusion, this finite element method can be used to study and compare cell area and strut distribution changes of bent stents,and to provide a convenient tool for designers in testing and improving biomechanical characteristics of new stents.

  5. Beam Shear Design According to Eurocode 2 - Limitations for the Concrete Strut Inclinations

    Hagsten, Lars German; Hestbech, Lars; Fisker, Jakob


    The beam shear design method adopted in Eurocode 2 is based on a lower bound plastic solution. This method is combined with limitations on the concrete strut inclination, θ. These limitations are introduced to ensure acceptable crack width in the SLS. 7 full scale beams have been tested and are p......The beam shear design method adopted in Eurocode 2 is based on a lower bound plastic solution. This method is combined with limitations on the concrete strut inclination, θ. These limitations are introduced to ensure acceptable crack width in the SLS. 7 full scale beams have been tested...... and are presented. These beams are all designed to fail in shear and the shear reinforcement is designed for different values of the concrete strut inclinations (cot θ varies from 1.5 to 3.4). These tests indicate a clear connection between the values of the concrete strut inclinations and crack width in the SLS....... In cases where larger crack widths (w > 0.4 mm) can be accepted, larger values of the concrete strut inclinations can be chosen. This will lead to less shear reinforcements. The results are also compared with analytical analysis based on energy methods. At the SLS the beams are expected to be cracked...

  6. The stress-strain behavior of coronary stent struts is size dependent.

    Murphy, B P; Savage, P; McHugh, P E; Quinn, D F


    Coronary stents are used to re-establish the vascular lumen and flow conditions within the coronary arteries; the typical thickness of a stent strut is 100 microm, and average grain sizes of approximately 25 microm exist in stainless steel stents. The purpose of this study is to investigate the effect of strut size on the stress strain behavior of 316 L stainless steel. Other materials have shown a size dependence at the micron size scale; however, at present there are no studies that show a material property size dependence in coronary stents. Electropolished stainless steel stent struts within the size range of 60-500 microm were tensile tested. The results showed that within the size range of coronary stent struts a size dependent stress-strain relationship is required to describe the material. Finite element models of the final phase of fracture, i.e., void growth models, explained partially the reason for this size effect. This study demonstrated that a size based stress-strain relationship must be used to describe the tensile behavior material of 316 L stainless steel at the size scale of coronary stent struts.

  7. Refinement of Strut-and-Tie Model for Reinforced Concrete Deep Beams.

    Mohammad Panjehpour

    Full Text Available Deep beams are commonly used in tall buildings, offshore structures, and foundations. According to many codes and standards, strut-and-tie model (STM is recommended as a rational approach for deep beam analyses. This research focuses on the STM recommended by ACI 318-11 and AASHTO LRFD and uses experimental results to modify the strut effectiveness factor in STM for reinforced concrete (RC deep beams. This study aims to refine STM through the strut effectiveness factor and increase result accuracy. Six RC deep beams with different shear span to effective-depth ratios (a/d of 0.75, 1.00, 1.25, 1.50, 1.75, and 2.00 were experimentally tested under a four-point bending set-up. The ultimate shear strength of deep beams obtained from non-linear finite element modeling and STM recommended by ACI 318-11 as well as AASHTO LRFD (2012 were compared with the experimental results. An empirical equation was proposed to modify the principal tensile strain value in the bottle-shaped strut of deep beams. The equation of the strut effectiveness factor from AASHTTO LRFD was then modified through the aforementioned empirical equation. An investigation on the failure mode and crack propagation in RC deep beams subjected to load was also conducted.

  8. L-Shaped Columellar Strut in East Asian Nasal Tip Plasty

    Eun-Sang Dhong


    Full Text Available Background Nasal tip support is an essential consideration for rhinoplasty in East Asians.There are many techniques to improve tip projection, and among them, the columellar strut isthe most popular technique. However, the conventional design is less supportive for rotatingthe tip. The amount of harvestable septal cartilage is relatively small in East Asians. For anoptimal outcome, we propose an L-shaped design for applying the columellar strut.Methods To evaluate the anthropometric outcomes, the change in nasal tip projection andthe columella-labial angle were analyzed by comparing preoperative and postoperative photographs.The anthropometric study group consisted of 25 patients who underwent the sameoperative technique of an L-shaped strut graft using septal cartilage and were followed upfor more than 9 months.Results There were statistically significant differences between the preoperative and postoperativevalues in the nasal tip projection ratio and columella-labial angle. We did not observeany complications directly related to the L-shaped columellar strut in the anthropometricstudy group.Conclusions The L-shaped columellar strut has advantages not only in the controlling of tipprojection and rotation, but in that it needs a smaller amount of cartilage compared to theconventional septal extension graft. It can therefore be an alternative technique for nasal tipplasty when there is an insufficient amount of harvestable septal cartilage.

  9. Intravascular optical coherence tomography light scattering artifacts: merry-go-rounding, blooming, and ghost struts

    Mancuso, J. Jacob; Halaney, David L.; Elahi, Sahar; Ho, Derek; Wang, Tianyi; Ouyang, Yongjian; Dijkstra, Jouke; Milner, Thomas E.; Feldman, Marc D.


    We sought to elucidate the mechanisms underlying two common intravascular optical coherence tomography (IV-OCT) artifacts that occur when imaging metallic stents: "merry-go-rounding" (MGR), which is an increase in strut arc length (SAL), and "blooming," which is an increase in the strut reflection thickness (blooming thickness). Due to uncontrollable variables that occur in vivo, we performed an in vitro assessment of MGR and blooming in stented vessel phantoms. Using Xience V and Driver stents, we examined the effects of catheter offset, intimal strut coverage, and residual blood on SAL and blooming thickness in IV-OCT images. Catheter offset and strut coverage both caused minor MGR, while the greatest MGR effect resulted from light scattering by residual blood in the vessel lumen, with 1% hematocrit (Hct) causing a more than fourfold increase in SAL compared with saline (pResidual blood also resulted in blooming, with blooming thickness more than doubling when imaged in 0.5% Hct compared with saline (presidual blood in the imaging field, is the predominant cause of MGR. Light scattering also results in blooming, and a newly described artifact, three-dimensional-MGR, which results in "ghost struts" in B-scans.

  10. Four shells atomic model to computer the counting efficiency of electron-capture nuclides; Modelo de cuatro capas para calcular la eficiencia de deteccion en nucleidos que se desintegran por captura electronica pura

    Grau Malonda, A.; Fernandez Martinez, A.


    The present paper develops a four-shells atomic model in order to obtain the efficiency of detection in liquid scintillation courting, Mathematical expressions are given to calculate the probabilities of the 229 different atomic rearrangements so as the corresponding effective energies. This new model will permit the study of the influence of the different parameters upon the counting efficiency for nuclides of high atomic number. (Author) 7 refs.

  11. In situ fabrication of a perfect Pd/ZnO@ZIF-8 core-shell microsphere as an efficient catalyst by a ZnO support-induced ZIF-8 growth strategy

    Lin, Lu; Zhang, Tong; Liu, Haiou; Qiu, Jieshan; Zhang, Xiongfu


    Controllable encapsulation of nanoparticles with metal organic frameworks (MOFs) has been an efficient way to impart the unique chemical and physical properties of the nanoparticles to metal organic frameworks and create new types of multifunctional MOF core-shell materials with enhanced properties. Here, a novel ZnO support-induced encapsulation strategy is reported to efficiently fabricate a Pd/ZnO@ZIF-8 core-shell catalyst, with Pd/ZnO as the core and ZIF-8 as the shell. The novel synthesis procedure involves first loading Pd nanoparticles onto the surface of the ZnO microsphere to form a Pd/ZnO core and then coating the core with a layer of defect-free ZIF-8 shell via ZnO-induced in situ ZIF-8 growth to obtain the Pd/ZnO@ZIF-8 core-shell catalyst. It was crucial that the ZIF-8 was in situ formed from the ZnO core in an ethanol solution only containing 2-methylimidazole under mild conditions. This strategy allowed for the growth of ZIF-8 right on the surface of Pd/ZnO via the reaction between ZnO and the 2-methylimidazole ligands, and thus avoided the random deposition of ZIF-8 crystals on the Pd/ZnO core as in the case of the conventional ZIF-8 synthesis solution. Furthermore, use of ethanol as the solvent also favored achievement of the well-defined Pd/ZnO@ZIF-8 structure, since the ethanol solution of 2-methylimidazole was able to keep the balance between ZnO dissolution and ZIF-8 formation. The as-prepared Pd/ZnO@ZIF-8 core-shell microsphere as an efficient catalyst displayed excellent performance in terms of size-selectivity, stability and anti-poisoning in the liquid hydrogenations of alkenes.

  12. Finite element modeling of shell shape in the freshwater turtle Pseudemys concinna reveals a trade-off between mechanical strength and hydrodynamic efficiency.

    Rivera, Gabriel; Stayton, C Tristan


    Aquatic species can experience different selective pressures on morphology in different flow regimes. Species inhabiting lotic regimes often adapt to these conditions by evolving low-drag (i.e., streamlined) morphologies that reduce the likelihood of dislodgment or displacement. However, hydrodynamic factors are not the only selective pressures influencing organismal morphology and shapes well suited to flow conditions may compromise performance in other roles. We investigated the possibility of morphological trade-offs in the turtle Pseudemys concinna. Individuals living in lotic environments have flatter, more streamlined shells than those living in lentic environments; however, this flatter shape may also make the shells less capable of resisting predator-induced loads. We tested the idea that "lotic" shell shapes are weaker than "lentic" shell shapes, concomitantly examining effects of sex. Geometric morphometric data were used to transform an existing finite element shell model into a series of models corresponding to the shapes of individual turtles. Models were assigned identical material properties and loaded under identical conditions, and the stresses produced by a series of eight loads were extracted to describe the strength of the shells. "Lotic" shell shapes produced significantly higher stresses than "lentic" shell shapes, indicating that the former is weaker than the latter. Females had significantly stronger shell shapes than males, although these differences were less consistent than differences between flow regimes. We conclude that, despite the potential for many-to-one mapping of shell shape onto strength, P. concinna experiences a trade-off in shell shape between hydrodynamic and mechanical performance. This trade-off may be evident in many other turtle species or any other aquatic species that also depend on a shell for defense. However, evolution of body size may provide an avenue of escape from this trade-off in some cases, as changes in


    Putu Ratna Suryantini


    Full Text Available Abstract: Research on the seismic response of in-filled frame structure has been done with in-filled frame model as full and partial shell elements. The wall is considered active until the maximum load on the full shell models, while the partial shell model using the gradual load with the strength of the wall is considered inactive if the stress of the wall exceeded the wall strength The 4 storey hotel building with full wall in x-direction and wall with opening in y-direction were modeled in SAP 2000 as 3D infilled-frame using full and partial shell element. In Mxy models, both wall were included in the model, while in My models, only the wall in y-direction included. Therefore, 4 models were obtained, there are full shell model MxyShPn and MyShPn and partial shell model MyShPar and MyShPar. In addition, 2 diagonal strut models MxyS and MyS  and an open frame model MOF were made as comparison. Prior to model 3D structure, validation models were created using test result condited by other as reference. For that purphose 5 2D models were created there are open frame model MOF, single strut model MST, multiple strut model MSG, full shell model MShPn and  partial shell model MShPar. From validation models, it is apparent that the MxyShPar model mimic the behavior of tested structure better than the other models. From the 3D models analysis result show that the displacement in x-direction of MxyShPn, MxyShPar, MxyS were 89%, 85%, 84% smaller than those of MOF, respectively inclusion of wall in the models, also reduce the internal forces and reduse the natural period of the sctructure.

  14. 基于Struts2的网上书城系统的设计与实现%Design and Implementation of Online Bookstore Based on Struts2

    魏榴花; 王辉


    Online bookstore system based on Struts2 is a Web software project designed from a excellent Struts2 framework. Firstly the reason for online bookstore system’s existence is interpreted in this paper, then Struts2 framework and MVC design pattern is simply introduced here, afterwards design of functional module、structural design and Entity-Relationship diagram. Fi⁃nally processes of implementing online bookstore based on Struts2 are stated form multi-aspects such as validation framework、in⁃ternationalization implementation、filter allocation and so on.%基于Struts2的网上书城系统是基于Struts2优秀框架设计出来的Web软件项目。该文首先讲述了网上书城系统存在的必要性,接着简要的介绍了Struts2框架和MVC设计模式,然后阐述了整个系统的功能模块设计、系统的架构设计和系统的E-R图。最后从校验框架、实现国际化、过滤器的配置等多方面来阐述用Struts2实现网上书城系统的详细过程。

  15. Struts+EJB框架技术在Web开发中的应用



    在Java EE平台体系中,关于Web开发的技术框架有很多种组合.本文首先简单介绍了Struts与EJB技术的各自特点;然后以Struts+EJB整合为例,详细介绍了整合之后的系统架构以及设计与实现的技术约束,并简单介绍了Struts+EJB整合的特点.通过这篇文章,可以了解到使用Struts+EJB进行Web系统开发,不仅可以构造一个健壮、稳定、易扩展、易维护的B/S架构的应用系统,而且可以大大提高了Web应用开发的效率.

  16. Hearing Gain with Tailor-made Polyethylene Strut in Total Stapedectomy

    Kanthong Thongyai


    Full Text Available Objective: To study audiometric changes after total stapedectomy with tailor-made polyethylene strut. Methods: A retrospective analysis of preoperative and postoperative hearing results. One hundred and ninety- eight patients underwent total stapedectomy during 2009-2014. Stapedectomy was performed with tailor-made polyethylene strut prosthesis on vein or perichondrium graft over oval window. Changes of preoperative and postoperative pure tone average (PTA were calculated from 4 frequencies after stapedectomy. Results: Ninety percent success rate in the air-bone gap closure within 10 dB after stapedectomy. Conclusion: Tailor-made polyethylene strut prosthesis is a cheap and cost-effective prosthesis, which is an alternative option for surgeons instead of the commercial prosthesis.

  17. Track-position and vibration control simulation for strut of the Stewart platform

    Zhao-dong XU; Chen-hui WENG


    Vibrations inherently generated by on-board disturbance sources degrade the performance of the instruments in an on-orbit spacecraft, which have stringent accuracy requirements.The Stewart platform enables both track-positioning and vibration control.The strut of the Stewart platform is designed as a piezoelectric (PZT) element in series with a voice coil motor (VCM) element and a viscoelastic element.The track-positioning system uses a VCM as the main positioning control driver and a PZT as the positioning compensator.The vibration control system uses the characteristics of struts including active and passive control elements to attenuate the vibration.Simulation results indicate that the Stewart platform with the designed struts has good performance in tracking and vibration attenuation with different interference waves.

  18. Multi-Shell Shell Model for Heavy Nuclei

    Sun, Yang; Wu, Cheng-Li


    Performing a shell model calculation for heavy nuclei has been a long-standing problem in nuclear physics. Here we propose one possible solution. The central idea of this proposal is to take the advantages of two existing models, the Projected Shell Model (PSM) and the Fermion Dynamical Symmetry Model (FDSM), to construct a multi-shell shell model. The PSM is an efficient method of coupling quasi-particle excitations to the high-spin rotational motion, whereas the FDSM contains a successful t...

  19. Microstructure and homogeneity of distribution of mineralised struts determine callus strength

    M Mehta


    Full Text Available Non-invasive assessment of fracture healing, both in clinical and animal studies, has gained favour as surrogate measure to estimate regain of mechanical function. Micro-computed tomography (µCT parameters such as fracture callus volume and mineralisation have been used to estimate callus mechanical competence. However, no in-depth information has been reported on microstructural parameters in estimating callus mechanical competence. The goal of this study is to use differently conditioned mice exhibiting good and impaired fracture healing outcomes and investigate the relationship between µCT imaging parameters (volume, mineralisation, and microstructure that best estimate the callus strength and stiffness as it develops over time. A total of 99 mice with femoral fracture and intramedullary stabilisation were divided into four groups according to conditioning: wild type, NF1 knock-out, RAG1 knock-out and macrophage depleted. Animals were sacrificed at 14, 21, 28 or 35 days and µCT parameters and torsional stiffness and strength were assessed post-sacrifice. Using linear regression for all groups and time points together, torsional stiffness could be estimated with strut thickness, strut number and strut homogeneity (R2 = 0.546, p < 0.0001; torsional strength could be estimated using bone mineral density, strut thickness and strut homogeneity (R2 = 0.568, p < 0.0001. Differently conditioned mice that result in different fracture healing outcomes have been shown to result in varying structural, material and volumetric µCT parameters which can be used to estimate regain of bone strength. This study is the first to demonstrate that microstructure and strut homogeneity influence callus stiffness and strength.

  20. 基于Struts+Spring+Hibernate的高校学生管理系统的设计与实现%Design and implement of university student management system based on Struts+Spring+Hibernate

    张烨; 王伯槐


    The Student Management System plays the most important role in the student management affairs in university.We have explored the theory and technologies of student management systems. Based on the analysis of the system requirements the actual of school, B/S development modules and layer structures were employed in implementing the system.The system was classified into representation layer,WEB layer,logic layer (business logic interface and business logic implementation class),data layer by utilizing Java EE framework technology struts+spring+hibernate),we have implemented the corresponding functions of student management system and conducted relevant tests. The results indicated that the system's feasibility and effectiveness achieved the desired goals. Its applications in realities have reduced the workload of the managers and improved the efficiencies.%在高校的日常工作中,学生管理系统占有举足轻重的地位.通过对学生管理系统相关理论技术进行深入研究,充分系统需求分析的基础上,结合学校的实际情况,采用B/S开发模式的多层体系方法,应用轻量级的Java EE框架技术(Struts+Spring+Hibernate),将系统划分为表示层、业务逻辑层、数据持久层,详细设计并实现了学生管理系统的相应功能,并进行了相关测试.测试结果表明系统的可行性和有效性达到了预期的目标,其应用能有效减少管理者的工作量、提高学生管理的工作效率.

  1. Ignition and Flame Stabilization of a Strut-Jet RBCC Combustor with Small Rocket Exhaust

    Jichao Hu; Juntao Chang; Wen Bao


    A Rocket Based Combined Cycle combustor model is tested at a ground direct connected rig to investigate the flame holding characteristics with a small rocket exhaust using liquid kerosene. The total temperature and the Mach number of the vitiated air flow, at exit of the nozzle are 1505 K and 2.6, respectively. The rocket base is embedded in a fuel injecting strut and mounted in the center of the combustor. The wall of the combustor is flush, without any reward step or cavity, so the strut-je...

  2. System structural test results - Six PODS III supports. [Passive Orbital Disconnect Struts

    Parmley, Richard T.; Kittel, Peter


    Passive orbital disconnect struts can potentially reduce the support conductance a factor of 10 over state-of-the-art tension band nondisconnect supports and cut helium dewar weights in half for the same lifetime. A series of thermal and structural tests were performed to verify that this performance improvement is real. Structural tests on a PODS-III support system (consisting of six struts) is reported here. The results show the predicted performance improvements can be achieved and the PODS-III supports are ready for flight applications. For large tankage systems requiring higher side load capability, a PODS-IV version is currently being developed.

  3. Polylactide bioabsorbable struts for chest wall reconstruction in a pediatric patient.

    Makarawo, Tafadzwa P; Reynolds, Richard A; Cullen, Marc L


    Chest wall reconstruction after pediatric tumor resection is challenging. Children have unique characteristics related to growth and prosthetic material for reconstruction must be chosen carefully. Poly-L-Lactide (PLA), a bioabsorbable prosthetic material, has been used in the plate form for reconstruction after tumor resection in children. Recently developed PLA struts have been successfully used to reconstruct pediatric chest wall deformities. This is the first description of the use of PLA rib struts to reconstruct chest wall defects after a pediatric chest wall tumor resection. Copyright © 2015 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

  4. Influence of Ring Stiffeners on a Steel Cylindrical Shell

    D. Lemák


    Full Text Available Shell structures are usually formed from concrete, steel and nowadays also from many others materials. Steel is typically used in the structures of chimneys, reservoirs, silos, pipelines, etc. Unlike concrete shells, steel shells are regularly stiffened with the help of longitudinal and/or ring stiffeners.The authors of this paper investigated steel cylindrical shells and their stiffening with the use of ring stiffeners. The more complete the stiffening, the more closely the shell will act to beam theory, and the calculations will be much easier. However, this would make realization of the structure more expensive and more laborious. The target of the study is to find the limits of ring stiffeners for cylindrical shells. Adequate stiffeners will eliminate semi-bending action of the shells in such way that the shell structures can be analyzed with the use of numerical models of the struts (e.g., by beam theory without significant divergences from reality. Recommendations are made for the design of ring stiffeners, especially for the distances between stiffeners and for their bending stiffness. 

  5. Effects of brown fish meal replacement with fermented soybean meal on growth performance, feed efficiency and enzyme activities of Chinese soft-shelled turtle, Pelodiscus sinensis

    Zou, Yurong; Ai, Qinghui; Mai, Kangsen; Zhang, Wenbing; Zhang, Yanjiao; Xu, Wei


    A 120-day feeding experiment was conducted to investigate the effects of partial replacement of brown fish meal (BFM) by fermented soybean meal (FSBM) in diets of Chinese soft-shelled turtle ( Pelodiscus sinensis). The turtles (initial mean body weight, (115.52 ± 1.05) g) were fed with three experimental diets, in which 0%, 4.72% and 9.44% BFM protein was replaced by 0%, 3% and 6% FSBM, respectively. Results showed that the feeding rate (FR), specific growth rate (SGR) and feed efficiency ratio (FER) of turtles fed with the diet containing 3% FSBM were not significantly different from the control group (0% FSBM) ( P > 0.05). However, FR, SGR and FER of turtles fed with the diet containing 6% FSBM were significantly lower than those of the control group ( P 0.05). However, the uric acid concentration in turtles fed with the diet containing 3% or 6% FSBM was significantly lower than that in the control group ( P 0.05). The results suggested that FSBM could replace 4.72% BFM protein in turtle diets without exerting adverse effects on turtle growth, feed utilization and measured immune parameters.

  6. 基于 Struts+Spring的动态概率选课系统设计%Design of Dynamic Probability Course Selection System Based on Struts+Spring

    周洁; 杨静


    To analyze the problems of the current institute. NET platform course selection system: the current course selection system uses the algorithms of the first come the first service, a large number of students to select courses will make the server load increase, the result will lead to denial service. Analyzing stratified volunteer, based on neural network characteristics and college course selection system its own characteristics, a dynamic real-time probabilistic algorithm solving a class selection lottery fairness issues is proposed. The course selection system platform uses J2EE Struts framework and Spring technolosy, which uses the structure of MVC not only to achieve the function module and the display module separation, but also to increase application scalability, portability and reusability of components. Object-oriented analysis with UML and modeling ideas optimizes the elective systern, enhances the efficiency of system operation, and achieves good elective management functions.%分析当前学院的.NET平台的选修课系统存在的问题:选课系统采用先到先服务的算法,当学生大量选课时会导致服务器负载加重,产生拒绝服务的现象.在分析多志愿分级处理算法、基于神经网络选课系统的特点和学院自身特点的基础上,提出以动态概率实时抽签算法解决学生选课公平性问题,选课系统采用J2EE平台的Struts框架和Spring技术,这种MVC系统结构的采用不仅实现功能模块和显示模块的分离,同时它还提高应用系统的可扩展性、可移植性和组件的可复用性.采用UML面向对象分析与建模的思想,实现本校选课系统的优化,提升系统运行的效率,并实现良好的选课管理的功能.

  7. Optical coherence tomography at follow-up after percutaneous coronary intervention: relationship between procedural dissections, stent strut malapposition and stent healing

    Radu, Maria; Jørgensen, Erik; Kelbæk, Henning;


    To analyse the relationship between strut apposition as visualised with optical coherence tomography (OCT) at follow-up and clinical and procedural characteristics at stent implantation, and to examine the relationship between strut apposition and stent healing.......To analyse the relationship between strut apposition as visualised with optical coherence tomography (OCT) at follow-up and clinical and procedural characteristics at stent implantation, and to examine the relationship between strut apposition and stent healing....

  8. Dynamic characteristics and performance evaluation for the part strut failure of the vibration isolation platform on satellites

    Zhang, Yao; Sheng, Chao; Guo, Zixi; Wang, Youyi; Li, Wenbo


    The dynamic characteristics and performance evaluation for the part strut failure of the vibration isolation platform are presented in this paper. The first step provides and mathematically describes two types of strut failure: fractured and stuck. Secondly, the dynamic model of the vibration isolation platform, which considers the part strut failure, is established using the Newton-Euler method and a constraint equation to evaluate its dynamic characteristics and performance. Then, with reasonable assumptions, the dynamic model of the satellite, which has a vibration isolation platform and vibration sources (such as control moment gyros) of three working situations (without and with two types of strut failure), is simplified to analyse the frequency domain characteristic and coupling characteristic with the attitude control system. Finally, a numerical simulation is used to study the effect of the vibration isolation platform with part strut failure on the attitude control and stabilization, and the attitude control performance is evaluated.

  9. 基于Web项目开发中的Struts2技术探讨%Struts2 Technology Based on the Web Project Development




  10. Application Research of Java Web Based on Struts2 and Hibernate Framework%基于Struts2与Hibernate框架的Java Web应用研究

    欧阳宏基; 葛萌


    传统Java Web开发存在着分层不明确、系统耦合度高、业务逻辑与JDBC混为一体等缺点,针对上述问题提出集成Struts2与Hibernate框架进行Web开发的方案.按照分层开发的思想降低层与层之间的耦合度,利用Struts2完成系统的控制逻辑,利用DAO模式封装Hibernate完成业务实体对象与数据库表的ORM映射.将该方案应用于实验室管理系统的开发,详细描述了系统实现的主要过程与若干关键技术.通过实践表明:集成Struts2与Hibernate框架的Web应用具备开发的高效性、复用性和可扩展性.

  11. Analysis of reinforced concrete shells with transverse shear forces

    Schulz, Mauro


    This research investigates the simultaneous effect of in-plane and transverse loads in reinforced concrete shells. The infinitesimal shell element is divided into layers (with triaxial behavior) that are analyzed according to the smeared rotating crack approach. The set of internals forces includes the derivatives of the in-plane components. The corresponding generalized strains are determined using an extension of the equivalent section method, valid for shells. The formulation yields through-the-thickness distributions of stresses and strains and the spatial orientation of the concrete struts. Although some simplifications are necessary to establish a practical first-order approximation, higher-order solutions could be developed. Despite the fact that constitutive matrices are not symmetric, because of the tension-softening formulation, the equilibrium and compatibility conditions are satisfied, the stiffness derivatives are explicitly calculated and the algorithms show good convergence. The formulation pre...

  12. Euler Strut: A Mechanical Analogy for Dynamics in the Vicinity of a Critical Point

    Bobnar, Jaka; Susman, Katarina; Parsegian, V. Adrian; Rand, Peter R.; Cepic, Mojca; Podgornik, Rudolf


    An anchored elastic filament (Euler strut) under an external point load applied to its free end is a simple model for a second-order phase transition. In the static case, a load greater than the critical load causes a Euler buckling instability, leading to a change in the filament's shape. The analysis of filament dynamics with an external point…

  13. Development of an experimental method to determine the axial rigidity of a strut-node joint

    Brewer, W. V.; Shih, Hui-Ru


    The following are presented: the experimental procedure and the results that have been performed to determine the axial rigidity of the strut-node joint; and the method for modifying a simple testing machine to make it capable of performing more accurate tests over a specific load range and able to accept larger test assemblies.

  14. Euler Strut: A Mechanical Analogy for Dynamics in the Vicinity of a Critical Point

    Bobnar, Jaka; Susman, Katarina; Parsegian, V. Adrian; Rand, Peter R.; Cepic, Mojca; Podgornik, Rudolf


    An anchored elastic filament (Euler strut) under an external point load applied to its free end is a simple model for a second-order phase transition. In the static case, a load greater than the critical load causes a Euler buckling instability, leading to a change in the filament's shape. The analysis of filament dynamics with an external point…

  15. Microscale diffusion measurements and simulation of a scaffold with a permeable strut.

    Lee, Seung Youl; Lee, Byung Ryong; Lee, Jongwan; Kim, Seongjun; Kim, Jung Kyung; Jeong, Young Hun; Jin, Songwan


    Electrospun nanofibrous structures provide good performance to scaffolds in tissue engineering. We measured the local diffusion coefficients of 3-kDa FITC-dextran in line patterns of electrospun nanofibrous structures fabricated by the direct-write electrospinning (DWES) technique using the fluorescence recovery after photobleaching (FRAP) method. No significant differences were detected between DWES line patterns fabricated with polymer supplied at flow rates of 0.1 and 0.5 mL/h. The oxygen diffusion coefficients of samples were estimated to be ~92%-94% of the oxygen diffusion coefficient in water based on the measured diffusion coefficient of 3-kDa FITC-dextran. We also simulated cell growth and distribution within spatially patterned scaffolds with struts consisting of either oxygen-permeable or non-permeable material. The permeable strut scaffolds exhibited enhanced cell growth. Saturated depths at which cells could grow to confluence were 15% deeper for the permeable strut scaffolds than for the non-permeable strut scaffold.

  16. Modeling of size dependent failure in cardiovascular stent struts under tension and bending.

    Harewood, F J; McHugh, P E


    Cardiovascular stents are cylindrical mesh-like metallic structures that are used to treat atherosclerosis. The thickness of stent struts are typically in the range of 50-150 microm. At this microscopic size scale, the tensile failure strain has been shown to be size dependent. Micromechanically representative computational models have captured this size effect in tension. In this paper polycrystalline models incorporating material fracture are used to investigate size effects for realistic stent strut geometries and loading modes. The specific loading a stent undergoes during deployment is uniquely captured and the implications for stent design are considered. Fracture analysis is also performed, identifying trends in terms of strut thickness and loading type. The results show, in addition to the size effect in tension, further size effects in different loading conditions. The results of the loading analyses are combined to produce a tension and bending failure graph. This design safety diagram is presented as a tool to predict failure of stent struts. This study is particularly significant given the current interest in producing smaller stents.

  17. Microscale Diffusion Measurements and Simulation of a Scaffold with a Permeable Strut

    Songwan Jin


    Full Text Available Electrospun nanofibrous structures provide good performance to scaffolds in tissue engineering. We measured the local diffusion coefficients of 3-kDa FITC-dextran in line patterns of electrospun nanofibrous structures fabricated by the direct-write electrospinning (DWES technique using the fluorescence recovery after photobleaching (FRAP method. No significant differences were detected between DWES line patterns fabricated with polymer supplied at flow rates of 0.1 and 0.5 mL/h. The oxygen diffusion coefficients of samples were estimated to be ~92%–94% of the oxygen diffusion coefficient in water based on the measured diffusion coefficient of 3-kDa FITC-dextran. We also simulated cell growth and distribution within spatially patterned scaffolds with struts consisting of either oxygen-permeable or non-permeable material. The permeable strut scaffolds exhibited enhanced cell growth. Saturated depths at which cells could grow to confluence were 15% deeper for the permeable strut scaffolds than for the non-permeable strut scaffold.

  18. Struts Analysis and Its Application Research%Struts分析及其应用研究

    吴寅斐; 何钦铭; 吴大瑞



  19. Shell supports

    Almegaard, Henrik


    A new statical and conceptual model for membrane shell structures - the stringer system - has been found. The principle was first published at the IASS conference in Copenhagen (OHL91), and later the theory has been further developed (ALMO3)(ALMO4). From the analysis of the stringer model it can...... be concluded that all membrane shells can be described by a limited number of basic configurations of which quite a few have free edges....

  20. Fibular Strut Graft Augmentation for Open Reduction and Internal Fixation of Proximal Humerus Fractures

    Saltzman, Bryan M.; Erickson, Brandon J.; Harris, Joshua D.; Gupta, Anil K.; Mighell, Mark; Romeo, Anthony A.


    Background: Proximal humerus fractures are common problems plaguing the elderly population. Purpose: The purposes of this study were to determine the outcomes of fibular strut allografts in treatment of proximal humerus fractures with open reduction internal fixation (ORIF) and to present the authors’ preferred surgical technique. The hypothesis was that the use of fibular strut allografts in treating proximal humerus fractures with ORIF will provide low reoperation rates with acceptable outcomes. Study Design: Systematic review; Level of evidence, 4. Methods: A systematic review was registered with PROSPERO and performed with PRISMA (Preferred Reporting Items for Systematic reviews and Meta-Analyses) guidelines using 3 publicly available free databases. Therapeutic clinical outcome investigations reporting arthroscopic elbow outcomes with levels of evidence 1 through 4 were eligible for inclusion. All study, subject, and surgical technique demographics were analyzed and compared between continents and countries. Statistics were calculated using Student t tests, 1-way analysis of variance, chi-square tests, and 2-proportion Z tests. Results: Four studies met the inclusion criteria. While there is great heterogeneity existing in the literature surrounding use of a fibular strut allograft as an adjunct to ORIF of proximal humerus fractures, current evidence shows a humeral head screw penetration rate of 3.7% with acceptable functional outcome scores, with a reoperation rate of 4.4% at a weighted mean 80.78 weeks (1.55 years) of postoperative follow-up. Conclusion: There is great heterogeneity that exists in the literature surrounding the use of a fibular strut allograft as an adjunct to ORIF of proximal humerus fractures. Current evidence shows a screw penetration rate of 3.7% with acceptable functional outcome scores, demonstrating fibular strut allograft is a viable option for treating proximal humerus fractures. PMID:27504463

  1. Percutaneous Extraction of Embolized Intracardiac Inferior Vena Cava Filter Struts Using Fused Intracardiac Ultrasound and Electroanatomic Mapping.

    Hannawa, Kevin K; Good, Eric D; Haft, Jonathan W; Williams, David M


    This report describes the percutaneous extraction of embolized intracardiac inferior vena cava (IVC) filter struts using fluoroscopy and fused intracardiac echocardiography and three-dimensional electroanatomic mapping. Six patients with indwelling IVC filters placed at outside institutions 5 months to 14 years previously presented with cross-sectional imaging of the chest demonstrating fractured IVC filter struts embolized to the myocardial free wall (four patients) or interventricular septum (two patients). All embolized filter struts were successfully retrieved, and open heart surgery was avoided. Copyright © 2015 SIR. Published by Elsevier Inc. All rights reserved.

  2. Multi-Shell Shell Model for Heavy Nuclei

    Sun, Y; Sun, Yang; Wu, Cheng-Li


    Performing a shell model calculation for heavy nuclei has been a long-standing problem in nuclear physics. Here we propose one possible solution. The central idea of this proposal is to take the advantages of two existing models, the Projected Shell Model (PSM) and the Fermion Dynamical Symmetry Model (FDSM), to construct a multi-shell shell model. The PSM is an efficient method of coupling quasi-particle excitations to the high-spin rotational motion, whereas the FDSM contains a successful truncation scheme for the low-spin collective modes from the spherical to the well-deformed region. The new shell model is expected to describe simultaneously the single-particle and the low-lying collective excitations of all known types, yet keeping the model space tractable even for the heaviest nuclear systems.

  3. A new near-linear scaling, efficient and accurate, open-shell domain-based local pair natural orbital coupled cluster singles and doubles theory.

    Saitow, Masaaki; Becker, Ute; Riplinger, Christoph; Valeev, Edward F; Neese, Frank


    The Coupled-Cluster expansion, truncated after single and double excitations (CCSD), provides accurate and reliable molecular electronic wave functions and energies for many molecular systems around their equilibrium geometries. However, the high computational cost, which is well-known to scale as O(N(6)) with system size N, has limited its practical application to small systems consisting of not more than approximately 20-30 atoms. To overcome these limitations, low-order scaling approximations to CCSD have been intensively investigated over the past few years. In our previous work, we have shown that by combining the pair natural orbital (PNO) approach and the concept of orbital domains it is possible to achieve fully linear scaling CC implementations (DLPNO-CCSD and DLPNO-CCSD(T)) that recover around 99.9% of the total correlation energy [C. Riplinger et al., J. Chem. Phys. 144, 024109 (2016)]. The production level implementations of the DLPNO-CCSD and DLPNO-CCSD(T) methods were shown to be applicable to realistic systems composed of a few hundred atoms in a routine, black-box fashion on relatively modest hardware. In 2011, a reduced-scaling CCSD approach for high-spin open-shell unrestricted Hartree-Fock reference wave functions was proposed (UHF-LPNO-CCSD) [A. Hansen et al., J. Chem. Phys. 135, 214102 (2011)]. After a few years of experience with this method, a few shortcomings of UHF-LPNO-CCSD were noticed that required a redesign of the method, which is the subject of this paper. To this end, we employ the high-spin open-shell variant of the N-electron valence perturbation theory formalism to define the initial guess wave function, and consequently also the open-shell PNOs. The new PNO ansatz properly converges to the closed-shell limit since all truncations and approximations have been made in strict analogy to the closed-shell case. Furthermore, given the fact that the formalism uses a single set of orbitals, only a single PNO integral transformation is

  4. 圆形燃烧室支板火箭超燃冲压发动机数值模拟%Numerical simulation of strut-rocket scramjet with circular combustor

    秦飞; 何国强; 刘佩进; 李鹏飞


    For increasing the ability of ignition and flame holding of large scale scramjet, the strut-rocket scramjet is developed, which consists of main strut in isolator, strut rocket and circular combustor. The numerical simulation including multi-steps chemical mechanisms was developed to investigate the reactive flow characteristics for liquid hydrocarbon supersonic combustion in circular combustor strut-rocket scramjet which is combined with pylons and cavity. It is indicated that the combination of strut-rocket and pylons is the paramount mechanism for flame holding. The results show that the strut-rocket scramjet can provide robust ignition and combustion efficiency and wide operability for ambient liquid hydrocarbon fuel in large scale combnstor.%为了提高大尺寸超燃冲压发动机的掺混燃烧和火焰稳定能力,提出了以中心主支板和支板火箭进行点火和火焰稳定的超燃冲压发动机基本结构,采用轴对称的圆形燃烧室以及小支板和凹腔等混合增强方式,通过包含多步简化动力学的数值模拟方法,研究了支板、凹腔结构与圆形燃烧室的不同匹配关系.结果表明,隔离段中心主支板能有效提高燃料与空气的掺混度,支板火箭的富燃高温羽流在不同状态下均能实现可靠点火;圆形燃烧室结合多组小支板和凹腔能进一步增强燃料混合和高效燃烧.利用支板火箭与轴对称圆形燃烧室相结合能在较短燃烧室内实现高效燃烧,为将来开展大尺寸超燃冲压发动机燃烧技术研究奠定基础.

  5. 基于Spring+Struts+Hibernate的Web项目设计与研究%Design and Research of the Web Project based on Spring+Struts+Hibernate Framework

    毕好昌; 李心科



  6. Ruby on Rails与Struts+Hibernate架构之比较分析%Compare and Analysis between Ruby on Rails and Struts+Hibernate Frame



    Ruby on Rails是一个基于Ruby语言构建的全新Web应用程序架构,为Web应用程序开发提供了一种极其快捷的途径,正在和已经引起业界相当的兴趣.在给出了Ruby on Rails与轻量级J2EE架构Struts+Hibernate关键特性的基础上,从前端控制器、动作和模型,持久性框架三个方面对两种架构进行了比较.

  7. Evaluation of the effect of stent strut profile on shear stress distribution using statistical moments

    Mongrain Rosaire


    Full Text Available Abstract Background In-stent restenosis rates have been closely linked to the wall shear stress distribution within a stented arterial segment, which in turn is a function of stent design. Unfortunately, evaluation of hemodynamic performance can only be evaluated with long term clinical trials. In this work we introduce a set of metrics, based on statistical moments, that can be used to evaluate the hemodynamic performance of a stent in a standardized way. They are presented in the context of a 2D flow study, which analyzes the impact of different strut profiles on the wall shear stress distribution for stented coronary arteries. Results It was shown that the proposed metrics have the ability to evaluate hemodynamic performance quantitatively and compare it to a common standard. In the context of the simulations presented here, they show that stent's strut profile significantly affect the shear stress distribution along the arterial wall. They also demonstrates that more streamlined profiles exhibit better hemodynamic performance than the standard square and circular profiles. The proposed metrics can be used to compare results from different research groups, and provide an improved method of quantifying hemodynamic performance in comparison to traditional techniques. Conclusion The strut shape found in the latest generations of stents are commonly dictated by manufacturing limitations. This research shows, however, that strut design can play a fundamental role in the improvement of the hemodynamic performance of stents. Present results show that up to 96% of the area between struts is exposed to wall shear stress levels above the critical value for the onset of restenosis when a tear-drop strut profile is used, while the analogous value for a square profile is 19.4%. The conclusions drawn from the non-dimensional metrics introduced in this work show good agreement with an ordinary analysis of the wall shear stress distribution based on the

  8. Effect of core quantum-dot size on power-conversion-efficiency for silicon solar-cells implementing energy-down-shift using CdSe/ZnS core/shell quantum dots.

    Baek, Seung-Wook; Shim, Jae-Hyoung; Seung, Hyun-Min; Lee, Gon-Sub; Hong, Jin-Pyo; Lee, Kwang-Sup; Park, Jea-Gun


    Silicon solar cells mainly absorb visible light, although the sun emits ultraviolet (UV), visible, and infrared light. Because the surface reflectance of a textured surface with SiNX film on a silicon solar cell in the UV wavelength region (250-450 nm) is higher than ∼27%, silicon solar-cells cannot effectively convert UV light into photo-voltaic power. We implemented the concept of energy-down-shift using CdSe/ZnS core/shell quantum-dots (QDs) on p-type silicon solar-cells to absorb more UV light. CdSe/ZnS core/shell QDs demonstrated clear evidence of energy-down-shift, which absorbed UV light and emitted green-light photoluminescence signals at a wavelength of 542 nm. The implementation of 0.2 wt% (8.8 nm QDs layer) green-light emitting CdSe/ZnS core/shell QDs reduced the surface reflectance of the textured surface with SiNX film on a silicon solar-cell from 27% to 15% and enhanced the external quantum efficiency (EQE) of silicon solar-cells to around 30% in the UV wavelength region, thereby enhancing the power conversion efficiency (PCE) for p-type silicon solar-cells by 5.5%.

  9. Mixed-PtPd-shell PtPdCu nanoparticle nanotubes templated from copper nanowires as efficient and highly durable electrocatalysts

    Li, Hui-Hui; Cui, Chun-Hua; Zhao, Shuo; Yao, Hong-Bin; Gao, Min-Rui; Fan, Feng-Jia; Yu, Shu-Hong [National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, Anhui 230026 (China); Div. of Nanomaterials and Chemistry, Heifei National Lab. for Physical, Sciences at Microscale (China)


    The controlled synthesis of mixed-PtPd-shell PtPdCu-alloy nanoparticle nanotubes (ANNTs) is demonstrated by galvanic displacement with partially sacrificial copper-nanowire templates, and following the electrochemical leaching of the non-noble metal Cu in the acidic electrolyte. These core-shell catalysts significantly reduce the amount of expensive Pt and highly improve the electrocatalytic activity and durability through their modified electronic structure, atomic distribution, and 1D structure property. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  10. A study of high-altitude manned research aircraft employing strut-braced wings of high-aspect-ratio

    Smith, P. M.; Deyoung, J.; Lovell, W. A.; Price, J. E.; Washburn, G. F.


    The effect of increased wing aspect ratio of subsonic aircraft on configurations with and without strut bracing. Results indicate that an optimum cantilever configuration, with a wing aspect ratio of approximately 26, has a 19% improvement in cruise range when compared to a baseline concept with a wing aspect ratio of approximately 10. An optimum strut braced configuration, with a wing aspect ratio of approximately 28, has a 31% improvment in cruise range when compared to the same baseline concept. This improvement is mainly due to the estimated reduction in wing weight resulting from use of lifting struts. All configurations assume the same mission payload and fuel. The drag characteristics of the wings are enhanced with the use of laminar flow airfoils. A method for determining the extent of attainable natural laminar flow, and methods for preliminary structural design and for aerodynamic analysis of wings lifting struts are presented.

  11. Numerical Investigation on Hydrogen-Fueled Scramjet Combustor with Parallel Strut Fuel Injector at a Flight Mach Number of 6

    Krishna Pandey


    Full Text Available A numerical analysis of the inlet-combustor interaction and flow structure through a scramjet engine at a flight Mach number M = 6 with parallel injection (Strut with circular inlet is presented in the present research article. Three different angles of attack (α=-4°, α=0°, α=4° have been studied for parallel injection. The scramjet configuration used here is a modified version of DLR scramjet model. Fuel is injected at supersonic speed (M=2 through a parallel strut injector. For parallel injection, the shape of the strut is chosen in a way to produce strong stream wise vorticity and thus to enhance the hydrogen/air mixing inside the combustor. These numerical simulations are aimed to study the flow structure, supersonic mixing, and combustion phenomena for the three different types of geometries along with circular shaped strut configuration.

  12. Investigations on the Influence of the In-Stream Pylon and Strut on the Performance of a Scramjet Combustor

    Hao Ouyang


    Full Text Available The influence of the in-stream pylon and strut on the performance of scramjet combustor was experimentally and numerically investigated. The experiments were conducted with a direct-connect supersonic model combustor equipped with multiple cavities. The entrance parameter of combustor corresponds to scramjet flight Mach number 4.0 with a total temperature of 947 K. The research results show that, compared with the scramjet combustor without pylon and strut, the wall pressure and the thrust of the scramjet increase due to the improvement of mixing and combustion effect due to the pylon and strut. The total pressure loss caused by the strut is considerable whereas pylon influence is slight.

  13. Design and Implementation Freshmen Based on of Registration System for Struts Framework%基于Struts框架的迎新系统的设计与实现



    在数字化校园建设过程中,充分考虑高等学校发展中出现的大校区、多校区的趋势问题,通过分析传统方式下迎新工作的业务流程,提出基于Struts Web技术的网络数字迎新系统的方案,并就系统在校园阳光教育体系工程中的作用做出分析,达到实时反馈迎新数据,提升高校迎新工作的效率,逐步实现无纸化迎新的目的。%In the process of digital campus construction, big campus and multi-campus trends in the development of colleges and universities are sufficiently considered, through the analysis of workflow of the traditional way of registration system for freshmen, the scheme of digital registration network system program based on the Struts Web technology is proposed, the role of the scheme in the campus s t education system engineering is analyzed, the realtime data for freshmen registration are responded to promote work efficiency for freshmen registration of colleges and universities, and the purpose of the paperless office is gradually achieved.

  14. Efficiency

    I.P. van Staveren (Irene)


    textabstractThe dominant economic theory, neoclassical economics, employs a single economic evaluative criterion: efficiency. Moreover, it assigns this criterion a very specific meaning. Other – heterodox – schools of thought in economics tend to use more open concepts of efficiency, related to comm

  15. The Transport of Mass, Energy, and Entropy in Cryogenic Support Struts for Engineering Design

    Elchert, J. P.


    Engineers working to understand and reduce cryogenic boil-off must solve a. variety of transport problems. An important class of nonlinear problems involves the thermal and mechanical design of cryogenic struts. These classic problems are scattered about the literature and typically require too many resources to obtain. So, to save time for practicing engineers, the author presents this essay. Herein, a variety of new, old, and revisited analytical and finite difference solutions of the thermal problem are covered in this essay, along with commentary on approach and assumptions, This includes a few thermal radiation and conduction combined mode solution with a discussion on insulation, optimum emissivity, and geometrical phenomenon. Solutions to cooling and heat interception problems are also presented, including a discussion of the entropy generation. And the literature on the combined mechanical and thermal design of cryogenic support struts is reviewed with an introduction to the associated numerical methods.

  16. Active strut placement using integer programming for the CSI Revolutionary Model

    Padula, Sharon L.; Sandridge, Chris A.


    A method for determining the most effective locations for active struts on large space structures is developed and tested on the NASA CSI Evolutionary Model. Depending on the choice of weighting factors, the method can be used to maximize the maximum modal damping ratio or decay rate, or to maximize a mission-oriented measure of performance. Placement of 8, 16, and 32 active struts out of 1507 candidate truss elements is demonstrated. Preliminary estimates of damping enhancement are reported pending refined structural models and dynamic test results. The method can handle complicated FEM models wih a large number of truss elements and many target modes. It can treat each mode equally or it can emphasize the importance of selected modes. The method can eliminate some combinations of actuator locations based on topological constraints.

  17. The Transport of Mass, Energy, and Entropy in Cryogenic Support Struts for Engineering Design

    Elchert, J. P.


    Engineers working to understand and reduce cryogenic boil-off must solve a variety of transport problems. An important class of nonlinear problems involves the thermal and mechanical design of cryogenic struts. These classic problems are scattered about the literature and typically require too many resources to obtain. So, to save time for practicing engineers, the author presents this essay. Herein, a variety of new, old, and revisited analytical and finite difference solutions of the thermal problem are covered in this essay, along with commentary on approach and assumptions. This includes a few thermal radiation and conduction combined mode solutions with a discussion on insulation, optimum emissivity, and geometrical phenomenon. Solutions to cooling and heat interception problems are also presented, including a discussion of the entropy generation. The literature on the combined mechanical and thermal design of cryogenic support struts is reviewed with an introduction to the associated numerical methods.

  18. Extraction of a migrated coil from the Enterprise stent strut using a Solitaire AB stent.

    Ge, Huijian; Jin, Hengwei; Li, Youxiang; Lv, Xianli


    A 56-year-old woman was admitted to stent-assisted coiling for a 2-mm A1 aneurysm of the left anterior cerebral artery and a left 3-mm internal carotid artery aneurysm. While coiling the A1 aneurysm, the first 2 mm × 20 mm coil migrated through the 4.5 mm × 37 mm Enterprise stent struts, lodging at the distal anterior cerebral artery. A 4 mm × 15 mm Solitaire AB stent was used successfully in this case to remove the displaced coil. The A1 aneurysm was re-treated with a 2 mm × 40 mm coil after placement of the Enterprise stent, and the ophthalmic ICA aneurysm was also coiled through the stent struts. The patient was neurologically intact after treatment. © The Author(s) 2016.

  19. Potential flow evaluation of the interference effect of strut-through-appendage-tip model mounting technique and reduction of the effect using blowing and suction

    Mellish, Robert W.; Coder, David W.


    A parametric study based on incompressible, irrotational flow theory was conducted to evaluate the effect of strut support interference on the flow field about a model. The use of suction and blowing to correct the support interference is also investigated. Two struts were considered for numerical analysis, a small chord strut of constant cross section and a large chord strut of varying cross section, both attached to the tip of a model submarine sail. For the present study the SS N21 class and SSN 688 class sail geometries are utilized. To assess the level of strut interference, the presence fields on the surface of the sail and a flat representation of the hull were evaluated as follows. The flow field was computed for the model geometry without a strut attached (baseline configuration) and the results are compared with identical calculations for the model-strut combination. The calculated results are presented graphically as contour plots of the pressure coefficient (Cp). Contour plots of delta p (the difference between baseline ad sail-strut results) are utilized to identify regions of principal strut interference. Finally, suction and blowing was applied to minimize strut interference in areas considered important to hull boundary layer and sail flow that would affect wake measurements.

  20. Fabrication of Hierarchical Layer-by-Layer Assembled Diamond-based Core-Shell Nanocomposites as Highly Efficient Dye Absorbents for Wastewater Treatment

    Zhao, Xinna; Ma, Kai; Jiao, Tifeng; Xing, Ruirui; Ma, Xilong; Hu, Jie; Huang, Hao; Zhang, Lexin; Yan, Xuehai


    The effective chemical modification and self-assembly of diamond-based hierarchical composite materials are of key importance for a broad range of diamond applications. Herein, we report the preparation of novel core-shell diamond-based nanocomposites for dye adsorption toward wastewater treatment through a layer-by-layer (LbL) assembled strategy. The synthesis of the reported composites began with the carboxyl functionalization of microdiamond by the chemical modification of diamond@graphene oxide composite through the oxidation of diamond@graphite. The carboxyl-terminated microdiamond was then alternatively immersed in the aqueous solution of amine-containing polyethylenimine and carboxyl-containing poly acrylic acid, which led to the formation of adsorption layer on diamond surface. Alternating (self-limiting) immersions in the solutions of the amine-containing and carboxyl-containing polymers were continued until the desired number of shell layers were formed around the microdiamond. The obtained core-shell nanocomposites were successfully synthesized and characterized by morphological and spectral techniques, demonstrating higher surface areas and mesoporous structures for good dye adsorption capacities than nonporous solid diamond particles. The LbL-assembled core-shell nanocomposites thus obtained demonstrated great adsorption capacity by using two model dyes as pollutants for wastewater treatment. Therefore, the present work on LbL-assembled diamond-based composites provides new alternatives for developing diamond hybrids as well as nanomaterials towards wastewater treatment applications.

  1. 基于Struts2的运动员信息管理输入校验%Input validation on athletes information management based on Struts2



    Enrollment music class students,so the college needs more music equipments.The college always faces challenge of the comprehensive information management for music equipments.This paper conducted data integrity design based on the database design on accounting treatment system for music equipment management.Entity integrity was achieved by the primary key,and it designed primary key of three tables and described the syntax when created primary key;referentialted foreign key; user-defined integrity was achieved by designing the corresponding constraint for relevant fields.%基本Struts2校验框架研究输入校验,为系统开发提供支持。首先,通过图形描述了Struts2校验框架运行流程;然后,基于SQL Server数据库管理系统设计了运动员信息表的逻辑结构;最后,对运动员信息表的字段进行归类,设计了7种校验器的程序代码。本文的研究内容具有思路清晰、方法科学等特点。

  2. Web application with MVC mechanism realized by Struts%Struts实现MVC机制的Web应用

    王霓虹; 李金凤


    介绍了Struts,它是使用servlet和JavaServer Pages技术的一种Model-View-Controller实现.Struts为Java Web应用提供了现成的通用框架,可以大大提高Web应用的开发速度.同时通过一个例子来介绍用Struts实现MVC机制的Web应用.

  3. Lordosis restoration after Smith-Petersen osteotomies and interbody strut placement: a radiographic study in cadavers.

    Lee, Michael J; Wiater, Brett; Bransford, Richard J; Bellabarba, Carlo; Chapman, Jens R


    Six human lumbar cadaveric specimens evaluated after sequential steps in restoration of lumbar lordosis. To determine the effect of Smith-Petersen osteotomies (SPO) with concurrent interbody strut placement on lordosis in the lumbar spine. The importance of restoration of lumbar lordosis is well recognized. SPO have been suggested to yield roughly 10° of lordosis per level, whereas pedicle subtraction osteotomies have been shown to result in over 30° of lordosis restoration. Though the pedicle subtraction osteotomy can achieve greater degrees of lordosis, there is considerable surgical morbidity associated. We hypothesize that SPO with an interbody strut placed within the disc space will result significantly greater lordosis than SPO alone. Lateral radiographs of 6 human lumbar specimens were obtained after 3 interventions as follows: (1) lumbar spine without osteotomy in maximal extension, (2) after SPO at L2, L3, and L4 and held in maximal extension with pedicle screw fixation, and (3) after SPO at L2, L3, and L4 with interbody cage placement in L2-L3, L3-L4, and L4-L5 held in maximal extension with pedicle screw fixation. The mean lordosis in the intact specimens was 7.03° (standard deviation [SD], 2.21°). The mean lordosis after SPO was 11.05° (SD, 1.05°). The mean lordosis after SPO and interbody strut placement was 15.72° (SD, 3.19°). The difference in lordosis in the osteotomized specimens with and without interbody strut was significantly (P lordosis, significantly greater than that of SPO alone.

  4. Computational Analysis of Geometric Effects on Strut Induced Mixing in a Scramjet Combustor


    NASA also aided in the understanding of how VULCAN worked. Thanks to my advisor, Dr. Robert Greendyke, and the rest of the AFIT faculty for imparting...Magre, A. Bresson , F. Grisch, M. Orain, and M. Kodera, “Exper- imental study of strut injectors in a supersonic combustor using oh-plif,” AIAA Paper...OF RESPONSIBLE PERSON Dr. Robert Greendyke Associate Professor a. REPORT U b. ABSTRACT U c. THIS PAGE U 19b. TELEPHONE NUMBER (Include

  5. Finite Element Modeling of Deployment, and Foam Rigidization of Struts and Quarter Scale Shooting Star Experiment

    Leigh, Larry, Jr.


    Inflated cylindrical struts constructed of kapton polyimide film and rigidized with foam have considerable practical application and potential for use as components of inflatable concentrator assemblies, antenna structures and space power systems, Because of their importance, it is of great interest to characterize the dynamic behavior of these components and structures both experimentally and analytically. It is very helpful to take a building-block approach to modeling and understanding inflatable assemblies by first investigating in detail the behavior of the components such as the struts. The foam material used for rigidization of such cylinders has varying modulus, which is a function of different factors, such as density of the foam. Thus, the primary motivation of the tests and analytical modeling efforts was to determine and understand the response of foam-rigidized cylinders for different densities, sizes, and construction methods, In recent years, inflatable structures have been the subject of renewed interest for space applications such as communications antennae, solar thermal propulsion, and space solar power. A major advantage of using inflatable structures in space is that they are extremely lightweight. This makes inflatables a perfect match for solar thermal propulsion because of the low thrust levels available. An obvious second advantage is on-orbit deployability and subsequent space savings in launch configuration. It can be seen that inflatable cylindrical struts and torus are critical components of structural assemblies. In view of this importance, structural dynamic and static behaviors of typical rigidized polyimide struts are investigated in this paper. The paper will focus on the finite element models that were used to model the behavior of the complete solar collector structure, and the results that they provided, as compared to test data.

  6. Strut fracture in the new Bjørk-Shiley mitral valve prosthesis.

    Brubakk, O; Simonsen, S; Källman, L; Fredriksen, A


    The case of a patient with the new type Bjørk-Shiley aortic and mitral valve prosthesis is described. Three months after implant she suffered acute heart failure and died. Post-mortem examination revealed a fractured outlet strut in the mitral valve prosthesis with dislocation of the disc. The fracture was regarded as due to excessive brittleness caused by demonstrated deposition of chromium-tungsten-carbide.

  7. Equivalent Strut Method for the Modelling of Masonry Infill Walls in the Nonlinear Static Analysis of Buildings

    Adukadukam, A.; Sengupta, A. K.


    In the seismic analysis of a framed building with masonry infill walls, it is necessary to model the effect of the walls on the lateral stiffness, strength and ductility of the building. The equivalent strut method is convenient for modelling the walls in a large building. However, an appropriate axial load versus deformation relationship for the strut is required in a nonlinear static method of seismic analysis, such as the pushover analysis. The present study proposes a nonlinear axial hinge property for the strut, with suitable performance levels. First, the equivalent strut method and the suitability of two approaches available in the literature for modelling the properties of the struts, are briefly discussed. Next, the nonlinear axial load versus deformation relationship is developed based on experimental data compiled from the literature. The parabolic-plastic relationship is idealized as a tri-linear axial hinge property, so that it can be incorporated in commercial software for undertaking pushover analysis. Next, the use of the hinge property is demonstrated in the pushover analyses of two framed reinforced concrete buildings. The pushover curves based on the proposed hinge property shows improved modelling of the inelastic drifts of the buildings. Although the modelling of a wall using a single strut has limitations, the proposed methodology is practical for a pushover analysis of a building.

  8. Influence of strut inertia on the vibrations in initially symmetric Gough-Stewart Platforms-an analytical study

    Afzali-Far, Behrouz; Andersson, Anette; Nilsson, Kristina; Lidström, Per


    Consideration of strut inertia can have significant influence on the modal behavior of a Gough-Stewart Platform (GSP). However, in the literature, the strut inertia has not yet been taken into account in its vibration study with a parametric approach. In this paper, we present a fully parametric approach to formulate the damped vibrations of GSPs taking into account the strut masses and moments of inertia for symmetric configurations. For the first time, a combined 6×6 equivalent inertia matrix (mass matrix), including both the inertia properties of the platform and the struts, is formulated parametrically. Subsequently, the eigenvectors and the damped eigenfrequencies are also parametrically developed in the Cartesian space. Furthermore, the conditions for the decoupled vibrations and the effect of strut inertia on these conditions are analytically investigated. With the aid of a reference GSP, the influence of the strut inertia on its modal behavior is systematically investigated. Accordingly, it is concluded that the parametric equations established in this paper can be directly employed in the analysis, optimization and control of GSPs in any application.

  9. Early outcomes of proximal humerus fracture fixation with locking plate and intramedullary fibular strut graft.

    Tan, Edwin; Lie, Denny; Wong, M K


    Proximal humerus fractures are commonly encountered in elderly patients. Surgical treatment demonstrates high complication rates, including varus construct collapse and screw cutout. In this study, the authors evaluate the clinical outcome of locking plate fixation with intramedullary fibular strut graft augmentation as a primary surgical treatment in the prevention of early collapse and screw cutout. A total of 9 patients were evaluated. Surgery was performed for displaced proximal humerus fractures between April and December 2011. Patients were either class 2, 3, or 4, according to Neer classification. Mean patient age was 75.4 years. Preoperative and immediate, 6-week, and 3-month postoperative radiographs were evaluated. Head-shaft angles were measured to assess for varus collapse and displacement. Range of motion, complication rates, and functional recovery were also evaluated. Patients underwent open reduction and internal fixation with placement of an intramedullary fibular strut graft. Fixation was achieved with a Philos plate (Synthes, Oberdorf, Switzerland). Reduction and fixation were evaluated with radiographs. Passive exercises and range of motion were allowed immediately postoperatively, and all patients achieved active abduction and forward flexion 6 weeks postoperatively. Shoulder radiographs taken 12 weeks postoperatively revealed no loss of reduction or screw cutout. The introduction of the locking plate has improved outcomes. The addition of an intramedullary strut graft has shown improved preliminary results. Maintained reduction was observed in all 9 patients in the early postoperative period, and good functional motion was achieved. No incidence of screw cutout was recorded.

  10. Design and analysis of supporting structure with smart struts for active vibration isolation

    Kim, Byeongil; Washington, Gregory N.; Singh, Rajendra


    This research investigates a supporting structure with smart struts under a vibratory load. In the case of most rotorcraft, structure-borne noise and vibration transmitted from the gearbox contains multiple spectral elements and higher frequencies, which include gear mesh frequencies and their side bands. In order to manage this issue, significant research have been devoted to active smart struts which have tunable stiffness such that a higher level of attenuation is possible. However, present techniques on active control are restricted mostly to the control of single or multiple sinusoids and thus these are not applicable to manage modulated and multi-spectral signals. Therefore, enhanced control algorithms are required in order to achieve simultaneous attenuation of gear mesh frequencies and their side bands. Proposed algorithms employing two nonlinear methods and one model-based technique are examined in this study. Their performance is verified by comparing with conventional algorithms. Moreover, these algorithms are implemented to exhibit whether they are feasible to narrowband or broadband control through experiments with a single smart strut. Novel methodologies are expected to be applied to several active vibration and noise control practices such as vehicles and other engineering structures.

  11. Autogenous tibial strut grafts used in severe kyphoscoliosis:surgical policies and preliminary results

    CHEN Hui; QIU Yong; WANG Bin; YU Yang; ZHU Ze-zhang ZHU Li-hua


    Background Surgery for severe kyphoscoliosis is frequently unsatisfying because of loss of correction, high rate of pseudarthrosis and neurological complications.Several authors reported that the anterior fusion with strut grafts might improve the surgical outcome.This article describes and assesses the surgical strategies and the application of autogenous tibial strut in the treatment of severe kyphoscoliosis.Results The mean preoperative and postoperative kyphosis was 82°and 52°respectively, and the mean scoliosis was 84°and 44°respectively.Complications included pseudarthrosis (2 cases, one with graft fracture and the other with hook displacement), posterior elements fractures (4), pleura penetrations (3, in the plastic surgery of the thoracic cage), dura tear (2), exudative pleuritis (2, in the anterior surgery), and tibia fracture of the harvesting site (1).The mean loss of correction in coronal and sagittal plane was 6° and 7° respectively.Except for 1 case, the patients with incomplete paraplegia showed improvements to varying extents.Conclusion Autogenous tibial strut can provide excellent support to the kyphoscoliotic spine: it reduces pseudarthrodic rate, loss of correction and complications of graft harvest, it also prevents the occurrence of neurological impairment.

  12. One-step synthesis of novel PANI–Fe{sub 3}O{sub 4}@ZnO core–shell microspheres: An efficient photocatalyst under visible light irradiation

    Zhang, Xiaoyuan [School of Chemistry and Chemical Engineering, Shihezi University, Shihezi 832003, Xinjiang (China); Wu, Jianning; Meng, Guihua; Guo, Xuhong [School of Chemistry and Chemical Engineering, Shihezi University, Shihezi 832003, Xinjiang (China); Key Laboratory for Green Processing of Chemical Engineering of Xinjiang Bingtuan, Engineering Research Center of Materials-Oriented Chemical Engineering of Xinjiang Bingtuan, Shihezi 832003, Xinjiang (China); Key Laboratory of Materials-Oriented Chemical Engineering of Xinjiang Uygur Autonomous Region, Engineering Research Center of Materials-Oriented Chemical Engineering of Xinjiang Bingtuan, Shihezi 832003, Xinjiang (China); Liu, Chang [School of Chemistry and Chemical Engineering, Shihezi University, Shihezi 832003, Xinjiang (China); Liu, Zhiyong, E-mail: [School of Chemistry and Chemical Engineering, Shihezi University, Shihezi 832003, Xinjiang (China); Key Laboratory for Green Processing of Chemical Engineering of Xinjiang Bingtuan, Engineering Research Center of Materials-Oriented Chemical Engineering of Xinjiang Bingtuan, Shihezi 832003, Xinjiang (China); Key Laboratory of Materials-Oriented Chemical Engineering of Xinjiang Uygur Autonomous Region, Engineering Research Center of Materials-Oriented Chemical Engineering of Xinjiang Bingtuan, Shihezi 832003, Xinjiang (China)


    Graphical abstract: PANI–Fe{sub 3}O{sub 4}@ZnO core–shell composite with ZnO shell and PANI core, Fe{sub 3}O{sub 4}-OA was embedded in PANI, has enhanced photocatalytic activity under visible light irradiation and can be separated using an external magnet. - Highlights: • PANI–Fe{sub 3}O{sub 4}@ZnO composite are prepared by one-step for the first time. • The catalysts can be separated by applying an external magnet. • The composite displayed a high photocatalytic activity toward MB. - Abstract: For the first time, novel multifunctional superparamagnetic PANI–Fe{sub 3}O{sub 4}@ZnO core–shell composite photocatalysts with different PANI: ZnO ratios were synthesized by Pickering emulsion route in one step in the presence of ZnO nanoparticles. PANI–Fe{sub 3}O{sub 4}@ZnO core–shell microspheres consist of PANI core which embedded with Fe{sub 3}O{sub 4}-OA (oleic acid modified Fe{sub 3}O{sub 4}) nanoparticles and tunable ZnO shell thickness. The resulting samples were thoroughly studied by using X-ray diffraction (XRD), X-ray photoelectron spectra (XPS), transmission electron microscopy (TEM), scanning electron microscope (SEM) and energy dispersive X-ray spectroscopy (EDS). The catalytic activity of the as-prepared PANI–Fe{sub 3}O{sub 4}@ZnO core–shell microspheres is investigated by the degradation of MB under visible light irradiation. As expected, the as prepared PANI–Fe{sub 3}O{sub 4}@ZnO photocatalysts exhibit highly enhanced photocatalytic activities in the degradation of MB under visible light irradiation owing to fast separation of photo-generated electron-hole pairs. Significantly, the PANI–Fe{sub 3}O{sub 4}@ZnO catalysts can be separated from the reaction media by applying an external magnet, and can be reused for seven cycles without change in stability and degradation efficiency.

  13. 管壳式换热器布管对换热效率的影响%Effect of tube distribution on the heat-exchanging efficiency of Shell-and-Tube Heat Exchanger

    甘树坤; 崔丽; 谢毛毛; 吕雪飞


    The heat-exchanging efficiency is usually improved by the split-range tube distribution in the design of Shell-and-Tube Heat Exchanger.The ratios between each tube range have great influence on the heat-exchanging efficiency of heat exchanger.The result that the heat-exchanging efficiency of non-uniform distributing tube is higher than that of uniform distributing tube is proved by theoretical formula.%在管壳式换热器设计中,通常通过分程来提高换热效率,但在分程布管时,各管程的布管比例,对换热器的换热效率有较大的影响,本文通过推导证明了非均匀布管比均匀布管换热效率高的结论.

  14. Fe3O4@ZnO core-shell nanocomposites for efficient and repetitive removal of low density lipoprotein in plasma and on blood vessel

    Huang, Xiao; Lu, Juan; Yue, Danyang; Fan, Yijuan; Yi, Caixia; Wang, Xiaoying; Zhang, Mengxue; Pan, Jun


    Low density lipoprotein (LDL)-apheresis therapy, which directly removes LDL from plasma by LDL-adsorbents in vitro is found to be clinically effective and safe to lower the LDL content in blood to prevent cardiovascular disease. Thus, developing excellent LDL adsorbents are becoming more and more attractive. Herein, functional Fe3O4@ZnO core-shell nanocomposites have been synthesized by a facile and eco-friendly two-step method. Not only do they possess high LDL adsorption (in PBS/plasma as well as on blood vessels) and favorable magnetic targeting ability but they can also be reused conveniently, which offer the Fe3O4@ZnO core-shell nanocomposites significant potential in the removal of LDL in vitro and in vivo.

  15. NiSe@NiOOH Core-Shell Hyacinth-like Nanostructures on Nickel Foam Synthesized by in Situ Electrochemical Oxidation as an Efficient Electrocatalyst for the Oxygen Evolution Reaction.

    Li, Xiao; Han, Guan-Qun; Liu, Yan-Ru; Dong, Bin; Hu, Wen-Hui; Shang, Xiao; Chai, Yong-Ming; Liu, Chen-Guang


    NiSe@NiOOH core-shell hyacinth-like nanostructures supported on nickel foam (NF) have been successfully synthesized by a facile solvothermal selenization and subsequent in situ electrochemical oxidation (ISEO). First, the unique NiSe/NF nanopillar arrays were prepared in N,N-dimethylformamide (DMF) as a precursor template that can provide a large surface area, excellent conductivity, and robust support. Next, amorphous NiOOH covering the surface of NiSe nanopillars was fabricated by ISEO, as confirmed by XPS andEDX spectroscopy. SEM images revealed the hyacinth-like morphology of NiSe@NiOOH/NF with NiOOH as the shell and NiSe as the core. The electrochemical performance of NiSe@NiOOH/NF for the oxygen evolution reaction (OER) was investigated. NiSe@NiOOH/NF demonstrates an obviously enhanced OER activity with much lower overpotential of 332 mV at 50 mA cm(-2) compared to other Ni-based electrocatalysts. The low charge-transfer resistance (Rct), large electrochemical double-layer capacitance (Cdl) of electrochemically active surface areas (ECSAs), and excellent long-term stability of NiSe@NiOOH/NF confirm the enhancement of its electrochemical performance for the OER, which can be ascribed to the large amount of active sites derived from the amorphous NiOOH shell and the good conductivity and stability derived from the NiSe core. In addition, the synergistic effect between the NiSe core and NiOOH shell could serve for a highly efficient OER electrocatalyst.

  16. Green synthesis of the reduced graphene oxide-CuI quasi-shell-core nanocomposite: A highly efficient and stable solar-light-induced catalyst for organic dye degradation in water

    Choi, Jiha; Reddy, D. Amaranatha; Islam, M. Jahurul; Seo, Bora; Joo, Sang Hoon; Kim, Tae Kyu


    Surfactant-free, reduced graphene oxide (RGO)-CuI quasi-shell-core nanocomposites were successfully synthesized using ultra-sonication assisted chemical method at room temperature. The morphologies, structures and optical properties of the CuI and CuI-RGO nanocomposites were characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Fourier-transformed infrared spectroscopy (FTIR), UV-visible absorption spectroscopy, and photoluminescence (PL) spectroscopy. Morphological and structural analyses indicated that the CuI-RGO core-shell nanocomposites comprise single-crystalline face-centered cubic phase CuI nanostructures, coated with a thin RGO quasi-shell. Photocatalysis experiments revealed that the as-synthesized CuI-RGO nanocomposites exhibit remarkably enhanced photocatalytic activities and stabilities for photo degradation of Rhodamine-B (RhB) organic dye under simulated solar light irradiation. The photo degradation ability is strongly affected by the concentration of RGO in the nanocomposites; the highest photodegradation rate was obtained at a graphene loading content of 2 mg mL-1 nanocomposite. The remarkable photocatalytic performance of the CuI-RGO nanocomposites mainly originates from their unique adsorption and electron-accepting and electron-transporting properties of RGO. The present work provides a novel green synthetic route to producing CuI-RGO nanocomposites without toxic solvents or reducing agents, thereby providing highly efficient and stable solar light-induced RGO-CuI quasi-shell-core nanocomposites for organic dye photo degradation in water.

  17. One-Step Conversion from Core-Shell Metal-Organic Framework Materials to Cobalt and Nitrogen Codoped Carbon Nanopolyhedra with Hierarchically Porous Structure for Highly Efficient Oxygen Reduction.

    Hu, Zhaowen; Zhang, Zhengping; Li, Zhilin; Dou, Meiling; Wang, Feng


    Rational design of porous structure is an effective way to fabricate the nonprecious metal electrocatalysts (NPMCs) toward oxygen reduction reaction (ORR) with high activity comparable or even superior to Pt-based electrocatalysts. Herein, we demonstrate a facile synthetic route to fabricate cobalt and nitrogen codoped carbon nanopolyhedra with hierarchically porous structure (Co,N-HCNP) by one-step carbonization of core-shell structured ZIF-8@ZIF-67 crystals. The resultant Co,N-HCNP electrocatalyst possesses a unique hierarchically micro/mesoporous structure with internal micropores and external mesopores, of which sufficient exposure and accessibility of ORR active sites can be achieved due to the large specific surface area and efficient transport pathway. More importantly, the existence of ZIF-8 core in the core-shell structured ZIF-8@ZIF-67 can promote the homogeneous pyrolysis of ZIF-67 shell, leading to a uniform distribution of Co-Nx active sites for Co,N-HCNP. As a result, the well-designed Co,N-HCNP electrocatalyst exhibits remarkable ORR activity with a high onset potential comparable to the commercial Pt/C, a half-wave potential of 0.855 V (9 mV more positive than that of Pt/C), and a kinetic current density of 63.84 mA cm(-2) at 0.8 V (2.3-fold enhancement compared with that of Pt/C) in alkaline electrolyte. Furthermore, the Co,N-HCNP electrocatalyst also presents outstanding electrochemical durability and methanol tolerance in comparison with Pt/C. The unique hierarchically porous structure of Co,N-HCNP achieved in this work provides a new insight into the design and synthesis of nanoarchitecture with targeted pore structure and opens a new avenue for the synthesis of highly efficient NPMCs for ORR.

  18. Pressure Shell Approach to Integrated Environmental Protection

    Kennedy, Kriss J.


    The next generation of exploration mission human systems will require environmental protection such as radiation protection that is effective and efficient. In order to continue human exploration, habitat systems will require special shells to protect astronauts from hostile environments. The Pressure Shell Approach to integrated environmental (radiation) protection is a multi-layer shell that can be used for multifunctional environmental protection. Self-healing, self-repairing nano technologies and sensors are incorporated into the shell. This shell consists of multiple layers that can be tailored for specific environmental protection needs. Mainly, this innovation focuses on protecting crew from exposure to micrometeorites, thermal, solar flares, and galactic cosmic ray (GCR) radiation. The Pressure Shell Approach consists of a micrometeoroid and secondary ejecta protection layer; a thin, composite shell placed in between two layers that is non-structural; an open cavity layer that can be filled with water, regolith, or polyethylene foam; a thicker composite shell that is a structural load bearing that is placed between two layers; and a bladder coating on the interior composite shell. This multi-layer shell creates an effective radiation protection system. Most of its layers can be designed with the materials necessary for specific environments. In situ materials such as water or regolith can be added to the shell design for supplemental radiation protection.

  19. The energy-down-shift effect of Cd(0.5)Zn(0.5)S-ZnS core-shell quantum dots on power-conversion-efficiency enhancement in silicon solar cells.

    Baek, Seung-Wook; Shim, Jae-Hyoung; Park, Jea-Gun


    We found that Cd0.5Zn0.5S-ZnS core (4.2 nm in diameter)-shell (1.2 nm in thickness) quantum dots (QDs) demonstrated a typical energy-down-shift (2.76-4.96 → 2.81 eV), which absorb ultra-violet (UV) light (250-450 nm in wavelength) and emit blue visible light (∼442 nm in wavelength). They showed the quantum yield of ∼80% and their coating on the SiNX film textured p-type silicon solar-cells enhanced the external-quantum-efficiency (EQE) of ∼30% at 300-450 nm in wavelength, thereby enhancing the short-circuit-current-density (JSC) of ∼2.23 mA cm(-2) and the power-conversion-efficiency (PCE) of ∼1.08% (relatively ∼6.04% increase compared with the reference without QDs for p-type silicon solar-cells). In particular, the PCE peaked at a specific coating thickness of the Cd0.5Zn0.5S-ZnS core-shell QD layer; i.e., the 1.08% PCE enhancement at the 8.8 nm thick QD layer.

  20. Experimental study of cone-struts and cavity flameholders in a kerosene-fueled round scramjet combustor

    Zhang, Dongqing; Song, Wenyan


    Experimental investigations of liquid kerosene ignition and flameholding in a round supersonic combustor are presented. Three kinds of flameholders, a cone-struts structure, a cavity and the combination of the both, are studied for the kerosene ignition and flameholding. Results show that ignition and flameholding cannot be achieved by using the sole cone-struts flameholder, although flames are observed at the combustor outlet. The ignition and flameholding are achieved in a narrow range of equivalence ratios by using the cavity flameholder. This range is widened by employing the combination of the cone-struts and the cavity flameholders. It is observed that the back pressure disrupts the isolator entrance flow slightly by using the larger cone-struts (CR = 0.261). However, it does not happen when the smaller cone-struts (CR = 0.221) is employed. Then a characteristic air mass flow rate in the round combustor is redefined to calculate a modified Damkohler number that correlates the nonpremixed flame stability limits. The correlations are in good agreements with the experimental results.

  1. Influence of processing conditions on strut structure and compressive properties of cellular lattice structures fabricated by selective laser melting

    Qiu, Chunlei, E-mail: [School of Metallurgy and Materials, University of Birmingham, Edgbaston, Birmingham B15 2TT (United Kingdom); Yue, Sheng [School of Materials, University of Manchester, Manchester M13 9PL (United Kingdom); Research Complex at Harwell, Rutherford Appleton Laboratory, Didcot, Oxfordshire OX11 0FA (United Kingdom); Adkins, Nicholas J.E.; Ward, Mark; Hassanin, Hany [School of Metallurgy and Materials, University of Birmingham, Edgbaston, Birmingham B15 2TT (United Kingdom); Lee, Peter D., E-mail: [School of Materials, University of Manchester, Manchester M13 9PL (United Kingdom); Research Complex at Harwell, Rutherford Appleton Laboratory, Didcot, Oxfordshire OX11 0FA (United Kingdom); Withers, Philip J., E-mail: [School of Materials, University of Manchester, Manchester M13 9PL (United Kingdom); Research Complex at Harwell, Rutherford Appleton Laboratory, Didcot, Oxfordshire OX11 0FA (United Kingdom); Attallah, Moataz M., E-mail: [School of Metallurgy and Materials, University of Birmingham, Edgbaston, Birmingham B15 2TT (United Kingdom)


    AlSi10Mg cellular lattice structures have been fabricated by selective laser melting (SLM) using a range of laser scanning speeds and powers. The as-fabricated strut size, morphology and internal porosity were investigated using optical microscopy (OM), scanning electron microscopy (SEM) and X-ray microtomography (micro-CT) and correlated to the compressive properties of the structure. Strut diameter was found to increase monotonically with laser power while the porosity was largest at intermediate powers. Laser scanning speed was found to thicken the struts only at slow rates while the porosity was largest at intermediate speeds. High speed imaging showed the melt pool to be larger at high laser powers. Further the melt pool shape was found to vary cyclically over time, steadily growing before becoming increasingly instable and irregularly shaped before abruptly falling in size due to splashing of molten materials and the process repeating. Upon compressive loading, lattice deformation was homogeneous prior to the peak stress before falling sharply due to the creation of a (one strut wide) shear band at around 45° to the compression axis. The specific yield strength expressed as the yield stress/(yield stress of the aluminium × relative density) is not independent of processing conditions, suggesting that further improvements in properties can be achieved by process optimisation. Lattice struts failed near nodes by a mixture of ductile and brittle fracture.

  2. A randomized optical coherence tomography study of coronary stent strut coverage and luminal protrusion with rapamycin-eluting stents.

    Moore, Philip; Barlis, Peter; Spiro, Jonathan; Ghimire, Gopal; Roughton, Michael; Di Mario, Carlo; Wallis, William; Ilsley, Charles; Mitchell, Andrew; Mason, Mark; Kharbanda, Rajesh; Vincent, Peter; Sherwin, Spencer; Dalby, Miles


    We used optical coherence tomography, which has a resolution of Translumina, Hechingen, Germany) to examine neointimal thickness, stent strut coverage, and protrusion at 90 days. Twenty-four patients (n = 12 for each group) underwent stent deployment and invasive follow-up at 90 days with optical coherence tomography. The primary end point was binary stent strut coverage. Coprimary end points were neointimal thickness and stent strut luminal protrusion. No patient had angiographic restenosis. For polymer-coated and nonpolymer rapamycin-eluting stents, respectively, mean (SD), neointimal thickness was 77.2 (25.6) microm versus 191.2 (86.7) mum (p 10% of struts being uncovered. High-resolution imaging allowed development of the concept of the protrusion index, and >25% of struts protruded into the vessel lumen with the polymer-coated rapamycin-eluting stent compared with <5% with the nonpolymer rapamycin-eluting stent. These findings may have important implications for the risk of stent thrombosis and, therefore, future stent design. (An optical coherence tomography study to determine stent coverage in polymer coated versus bare metal rapamycin eluting stents. ORCA 1, from the Optimal Revascularization of the Coronary Arteries group; ISRCTN42475919).

  3. High Light Absorption and Charge Separation Efficiency at Low Applied Voltage from Sb-Doped SnO2/BiVO4 Core/Shell Nanorod-Array Photoanodes.

    Zhou, Lite; Zhao, Chenqi; Giri, Binod; Allen, Patrick; Xu, Xiaowei; Joshi, Hrushikesh; Fan, Yangyang; Titova, Lyubov V; Rao, Pratap M


    BiVO4 has become the top-performing semiconductor among photoanodes for photoelectrochemical water oxidation. However, BiVO4 photoanodes are still limited to a fraction of the theoretically possible photocurrent at low applied voltages because of modest charge transport properties and a trade-off between light absorption and charge separation efficiencies. Here, we investigate photoanodes composed of thin layers of BiVO4 coated onto Sb-doped SnO2 (Sb:SnO2) nanorod-arrays (Sb:SnO2/BiVO4 NRAs) and demonstrate a high value for the product of light absorption and charge separation efficiencies (ηabs × ηsep) of ∼51% at an applied voltage of 0.6 V versus the reversible hydrogen electrode, as determined by integration of the quantum efficiency over the standard AM 1.5G spectrum. To the best of our knowledge, this is one of the highest ηabs × ηsep efficiencies achieved to date at this voltage for nanowire-core/BiVO4-shell photoanodes. Moreover, although WO3 has recently been extensively studied as a core nanowire material for core/shell BiVO4 photoanodes, the Sb:SnO2/BiVO4 NRAs generate larger photocurrents, especially at low applied voltages. In addition, we present control experiments on planar Sb:SnO2/BiVO4 and WO3/BiVO4 heterojunctions, which indicate that Sb:SnO2 is more favorable as a core material. These results indicate that integration of Sb:SnO2 nanorod cores with other successful strategies such as doping and coating with oxygen evolution catalysts can move the performance of BiVO4 and related semiconductors closer to their theoretical potential.

  4. Methods for Controlling the Sideforce on Surface-Piercing Hydrofoil Struts


    When Dos Enfred) UNCLASIFIED ..LAIVIlITY CLASSIFICATION OF TMIS PAGE(Whon bae Entered)- -xigificantly- improved, strut-- wesitance -to. ventilation...Office of thie David W. Taylor Naval Ship R& D Center is considering the design of a large, ocean-going hydrofoil ship (HOC) with the following...length 5 - 7 m max turn rate 5 - 6 deg/s (c.f. PHM, TUCUMdCARI, 8 deg/s, 12 deg/s, respectively) design -speed 50 knots It is envisioned that turns will

  5. Influence of pore and strut shape on open cell metal foam bulk properties

    Kumar, Prashant; Hugo, Jean-Michel; Topin, Frederic; Vicente, Jerome


    The thermo-physical behavior of open-celled metal foams depends on their microscopic structure. An ideal periodic isotropic structure of tetrakaidecahedron shape i.e. Kelvin cell is studied. We have proposed an analytical model in order to obtain geometrical parameters correctly as they have substantial influence on thermal and hydraulic phenomena, where strut geometry is of prime importance. Various relationships between different geometrical parameters and porosities are presented. Consequently, empirical correlations are proposed to determine permeability and inertia coefficient using Ergun like model for computing pressure drop.

  6. Ruby on Rails与Struts+Hibernate架构之比较分析



    Ruby on Rails是一个基于Ruby语言构建的全新Web应用程序架构,为Web应用程序开发提供了一种极其快捷的途径,正在和已经引起业界相当的兴趣.在给出了Ruby on Rails与轻量级J2EE架构Struts+Hibernate关键特性的基础上,从前端控制器、动作和模型,持久性框架三个方面对两种架构进行了比较.

  7. Smart core-shell microgel support for acetyl coenzyme A synthetase: a step toward efficient synthesis of polyketide-based drugs.

    Dubey, Nidhi C; Tripathi, Bijay P; Stamm, Manfred; Ionov, Leonid


    The flexibility in tuning the structure and charge properties of PNIPAm microgels during their synthesis makes them a suitable choice for various biological applications. Two-step free radical polymerization, a common method employed for synthesis of core-shell microgel has been well adopted to obtain cationic poly(N-isopropylacrylamide-aminoethyl methacrylate) (PNIPAm-AEMA) shell and PNIPAm core. Scanning electron microscopy (SEM), dynamic light scattering (DLS), zeta potential, and ninhydrin assay suggests nearly monodispersed particles of cationic nature. Amino groups on the microgel provides suitable attachment point for covalent immobilization of acetyl coenzyme A synthetase (Acs) via 1-ethyl-3-(3-N,N- dimethylaminopropyl) carbodiimide (EDC) chemistry. On immobilization, 61.55% of initial activity of Acs has been retained, while Michaelis-Menten kinetics of the immobilized Acs indicates identical K(m) (Michaelis constant) but decrease in the V(max) (maximum substrate conversion rate) compared to free enzyme. Immobilized Acs shows an improvement in activity at wide temperature and pH range and also demonstrates good thermal, storage, and operational stability. The Acs-microgel bioconjugate has been successfully reused for four consecutive operation cycles with more than 50% initial activity.

  8. NIF Double Shell outer-shell experiments

    Merritt, E. C.; Montgomery, D. S.; Kline, J. L.; Daughton, W. S.; Wilson, D. C.; Dodd, E. S.; Renner, D. B.; Cardenas, T.; Batha, S. H.


    At the core of the Double Shell concept is the kinetic energy transfer from the outer shell to the inner shell via collision. This collision sets both the implosion shape of the inner shell, from imprinting of the shape of the outer shell, as well as the maximum energy available to compress the DT fuel. Therefore, it is crucial to be able to control the time-dependent shape of the outer shell, such that the outer shell is nominally round at the collision time. We present the experiment results from our sub-scale ( 1 MJ) NIF outer-shell only shape tuning campaign, where we vary shape by changing a turn-on time delay between the same pulse shape on the inner and outer cone beams. This type of shape tuning is unique to this platform and only possible since the Double Shell design uses a single-shock drive (4.5 ns reverse ramp pulse). The outer-shell only targets used a 5.75 mm diameter standard near-vacuum NIF hohlraum with 0.032 mg/cc He gas fill, and a Be capsule with 0.4% uniform Cu dopant, with 242 um thick ablator. We also present results from a third outer-shell only shot used to measure shell trajectory, which is critical in determining the shell impact time. This work conducted under the auspices of the U.S. DOE by LANL under contract DE-AC52-06NA25396.

  9. Research and Implementation of Web Application of Struts+Hibernate Framework Based on MVC Pattern%基于MVC模式的Struts+Hibernate框架的Web应用研究与实现

    刘贤金; 王光琼


    Struts+Hibernate使得Web框架具有良好的扩展性和动态灵活性.简介Struts框架各组件实现功能和Hibernate框架,通过一个Web资金管理系统实例,从系统分析设计、Struts组件设计、Hibernate ORM数据库映射设计等方面论述基于MVC模式的Struts+Hibernate框架的Web应用系统的实现方法.

  10. Develop Web application with MVC mechanism realized by Struts%Struts实现MVC机制的Web应用

    王霓虹; 李金凤


    Struts是使用servlet和JavaServer Pages技术的一种Model-View-Controller实现.Struts为Java Web应用提供了现成的通用框架,可以大大提高Web应用的开发速度.同时通过一个例子来介绍用Struts实现MVC机制的Web应用.%Struts is a kind of Model-View-Controller realization using servlet and JavaServer Pa- ges technology. Struts has provided the ready - made and general - purpose framework for Web applica- tion, it can enhance the development speed of Web application. Finally, an example based on Struts tech- nology is given.

  11. Biological effect of microengineered grooved stents on strut healing: a randomised OCT-based comparative study in humans

    Vesga, Boris; Hernandez, Hector; Higuera, Sergio; Gasior, Pawel; Echeveri, Dario; Delgado, Juan A; Dager, Antonio; Arana, Camilo; Simonton, Charles; Maehara, Akiko; Palmaz, Julio; Granada, Juan F


    Objective To evaluate the biological effect of microengineered stent grooves (MSG) on early strut healing in humans by performing optical coherence tomography (OCT) analysis 3 weeks following the implantation. Background In the experimental setting, MSG accelerate endothelial cell migration and reduce neointimal proliferation compared with bare metal stent (BMS). Methods A total of 37 patients undergoing percutaneous coronary intervention with de novo coronary lesions were randomly assigned to either MSG (n=19) or an identical BMS controls (n=18). All patients underwent OCT imaging at 3 weeks. A total of 7959 struts were included in the final analysis. Results At 3 weeks following stent implantation, almost all struts analysed (~97%) had evidence of tissue coverage. The percentage of partially covered struts was comparable between both groups. However, the percentage of fully embedded struts was higher in the BMS group (81.22%, 49.75–95.52) compared with the MSG group (74.21%, 58.85–86.38). The stent-level analysis demonstrated reduction in neointimal formation (neointimal hyperplasia area and volume reduction of ~14% and ~19%, respectively) in the MSG versus the BMS group. In the strut-level analysis, an even greater reduction (~22% in neointimal thickness) was seen in the MSG group. Layered neointimal was present in ~6% of the OCT frames in the BMS group while it was not present in the MSG group. Conclusions MSG induced a more homogeneous and predictable pattern of surface healing in the early stages following stent implantation. The biological effect of MSG on stent healing has the potential to improve the safety profile of current generation drug-eluting stents. Classifications BMS, OCT, clinical trials. PMID:28674616

  12. Passive Orbital Disconnect Strut (PODS 3), structural and thermal test program

    Parmley, R. T.


    A test program is undertaken to verify that the lifetime of a shuttle launchable dewar can be increased by using passive orbital disconnect struts (PODS). A detailed design is performed on the cold end (PODS-III) portion of the strut. Structural analysis of the thin-wall fiberglass tube allows selection of the optimum winding angle and tube dimensions. Structural tests on the thin-wall fiberglass tube measure both the tension and compression modulus at ambient and LN2 temperatures, the radial deflection versus side load, and the ultimate compression strength of the tube at LN2 temperature. The thermal expansion of the fiberglass tube plus Invar is also measured down to 78 K. The axial gap at the wedge portion of the stem is set based on these data. The PODS-III test article parts are fabricated and assembled using a detailed assembly procedure. The thermal conductants in the orbital configuration was measured for body temperatures between 5 and 40 K. This temperature range covers the predicted ground hold and orbit temperatures for vapor-cooled supports. The test results are then compared with heat leak values predicted before the test began. Side load, axial compression load, and tension load tests conclude the test program.

  13. Ignition and Flame Stabilization of a Strut-Jet RBCC Combustor with Small Rocket Exhaust

    Jichao Hu


    Full Text Available A Rocket Based Combined Cycle combustor model is tested at a ground direct connected rig to investigate the flame holding characteristics with a small rocket exhaust using liquid kerosene. The total temperature and the Mach number of the vitiated air flow, at exit of the nozzle are 1505 K and 2.6, respectively. The rocket base is embedded in a fuel injecting strut and mounted in the center of the combustor. The wall of the combustor is flush, without any reward step or cavity, so the strut-jet is used to make sure of the flame stabilization of the second combustion. Mass flow rate of the kerosene and oxygen injected into the rocket is set to be a small value, below 10% of the total fuel when the equivalence ratio of the second combustion is 1. The experiment has generated two different kinds of rocket exhaust: fuel rich and pure oxygen. Experiment result has shown that, with a relative small total mass flow rate of the rocket, the fuel rich rocket plume is not suitable for ignition and flame stabilization, while an oxygen plume condition is suitable. Then the paper conducts a series of experiments to investigate the combustion characteristics under this oxygen pilot method and found that the flame stabilization characteristics are different at different combustion modes.

  14. Three-Dimensional Printing of Hollow-Struts-Packed Bioceramic Scaffolds for Bone Regeneration.

    Luo, Yongxiang; Zhai, Dong; Huan, Zhiguang; Zhu, Haibo; Xia, Lunguo; Chang, Jiang; Wu, Chengtie


    Three-dimensional printing technologies have shown distinct advantages to create porous scaffolds with designed macropores for application in bone tissue engineering. However, until now, 3D-printed bioceramic scaffolds only possessing a single type of macropore have been reported. Generally, those scaffolds with a single type of macropore have relatively low porosity and pore surfaces, limited delivery of oxygen and nutrition to surviving cells, and new bone tissue formation in the center of the scaffolds. Therefore, in this work, we present a useful and facile method for preparing hollow-struts-packed (HSP) bioceramic scaffolds with designed macropores and multioriented hollow channels via a modified coaxial 3D printing strategy. The prepared HSP scaffolds combined high porosity and surface area with impressive mechanical strength. The unique hollow-struts structures of bioceramic scaffolds significantly improved cell attachment and proliferation and further promoted formation of new bone tissue in the center of the scaffolds, indicating that HSP ceramic scaffolds can be used for regeneration of large bone defects. In addition, the strategy can be used to prepare other HSP ceramic scaffolds, indicating a universal application for tissue engineering, mechanical engineering, catalysis, and environmental materials.

  15. Ignition and flame stabilization of a strut-jet RBCC combustor with small rocket exhaust.

    Hu, Jichao; Chang, Juntao; Bao, Wen


    A Rocket Based Combined Cycle combustor model is tested at a ground direct connected rig to investigate the flame holding characteristics with a small rocket exhaust using liquid kerosene. The total temperature and the Mach number of the vitiated air flow, at exit of the nozzle are 1505 K and 2.6, respectively. The rocket base is embedded in a fuel injecting strut and mounted in the center of the combustor. The wall of the combustor is flush, without any reward step or cavity, so the strut-jet is used to make sure of the flame stabilization of the second combustion. Mass flow rate of the kerosene and oxygen injected into the rocket is set to be a small value, below 10% of the total fuel when the equivalence ratio of the second combustion is 1. The experiment has generated two different kinds of rocket exhaust: fuel rich and pure oxygen. Experiment result has shown that, with a relative small total mass flow rate of the rocket, the fuel rich rocket plume is not suitable for ignition and flame stabilization, while an oxygen plume condition is suitable. Then the paper conducts a series of experiments to investigate the combustion characteristics under this oxygen pilot method and found that the flame stabilization characteristics are different at different combustion modes.

  16. Suitability of carbon fiber-reinforced polyetheretherketone cages for use as anterior struts following corpectomy.

    Heary, Robert F; Parvathreddy, Naresh K; Qayumi, Zainab S; Ali, Naiim S; Agarwal, Nitin


    OBJECTIVE Fibular allograft remains a widely used strut for corpectomy surgeries. The amount of graft material that can be packed into an allograft strut has not been quantified. Cages are an alternative to fibular allograft for fusion surgeries. The authors of this study assessed the suitability of carbon fiber-reinforced polyetheretherketone (CFRP) cages for anterior corpectomy surgeries. They further explored the parameters known to affect fusion rates in clinical practice. METHODS Six fibular allografts were tested at standard lengths. Three sets of carbon fiber cages (Bengal, DePuy Spine), each with a different footprint size but the same lengths, were tested. The allografts and cages were wrapped in adhesive, fluid-tight transparent barriers and filled with oil. The volume and weight of the oil instilled as well as the implant footprints were measured. The fibular allografts and cages were tested at 20-, 40-, and 50-mm lengths. Two investigators independently performed all measurements 5 times. Five CFRP cubes (1 × 1 × 1 cm) were tested under pure compression, and load versus displacement curves were plotted to determine the modulus of elasticity. RESULTS Significantly more oil fit in the CFRP cages than in the fibular allografts (p Carbon fiber-reinforced polyetheretherketone cages can accommodate much more graft material than can fibular allografts. In clinical practice, the ability to deliver greater amounts of graft material following a corpectomy may improve fusion rates.

  17. Towards high efficiency air-processed near-infrared responsive photovoltaics: bulk heterojunction solar cells based on PbS/CdS core-shell quantum dots and TiO2 nanorod arrays.

    Gonfa, Belete Atomsa; Kim, Mee Rahn; Delegan, Nazar; Tavares, Ana C; Izquierdo, Ricardo; Wu, Nianqiang; El Khakani, My Ali; Ma, Dongling


    Near infrared (NIR) PbS quantum dots (QDs) have attracted significant research interest in solar cell applications as they offer several advantages, such as tunable band gaps, capability of absorbing NIR photons, low cost solution processability and high potential for multiple exciton generation. Nonetheless, reports on solar cells based on NIR PbS/CdS core-shell QDs, which are in general more stable and better passivated than PbS QDs and thus more promising for solar cell applications, remain very rare. Herein we report high efficiency bulk heterojunction QD solar cells involving hydrothermally grown TiO2 nanorod arrays and PbS/CdS core-shell QDs processed in air (except for a device thermal annealing step) with a photoresponse extended to wavelengths >1200 nm and with a power conversion efficiency (PCE) as high as 4.43%. This efficiency was achieved by introducing a thin, sputter-deposited, uniform TiO2 seed layer to improve the interface between the TiO2 nanorod arrays and the front electrode, by optimizing TiO2 nanorod length and by conducting QD annealing treatment to enhance charge carrier transport. It was found that the effect of the seed layer became more obvious when the TiO2 nanorods were longer. Although photocurrent did not change much, both open circuit voltage and fill factor clearly changed with TiO2 nanorod length. This was mainly attributed to the variation of charge transport and recombination processes, as evidenced by series and shunt resistance studies. The optimal PCE was obtained at the nanorod length of ∼450 nm. Annealing is shown to further increase the PCE by ∼18%, because of the improvement of charge carrier transport in the devices as evidenced by considerably increased photocurrent. Our results clearly demonstrate the potential of the PbS/CdS core-shell QDs for the achievement of high PCE, solution processable and NIR responsive QD solar cells.

  18. The shell coal gasification process

    Koenders, L.O.M.; Zuideveld, P.O. [Shell Internationale Petroleum Maatschappij B.V., The Hague (Netherlands)


    Future Integrated Coal Gasification Combined Cycle (ICGCC) power plants will have superior environmental performance and efficiency. The Shell Coal Gasification Process (SCGP) is a clean coal technology, which can convert a wide range of coals into clean syngas for high efficiency electricity generation in an ICGCC plant. SCGP flexibility has been demonstrated for high-rank bituminous coals to low rank lignites and petroleum coke, and the process is well suited for combined cycle power generation, resulting in efficiencies of 42 to 46% (LHV), depending on choice of coal and gas turbine efficiency. In the Netherlands, a 250 MWe coal gasification combined cycle plant based on Shell technology has been built by Demkolec, a development partnership of the Dutch Electricity Generating Board (N.V. Sep). The construction of the unit was completed end 1993 and is now followed by start-up and a 3 year demonstration period, after that the plant will be part of the Dutch electricity generating system.

  19. Core/Shell NaGdF4:Nd3+/NaGdF4 Nanocrystals with Efficient Near-Infrared to Near-Infrared Downconversion Photoluminescence for Bioimaging Applications

    Chen, Guanying; Ohulchanskyy, Tymish Y.; Liu, Sha; Law, Wing-Cheung; Wu, Fang; Swihart, Mark T.; Ågren, Hans; Prasad, Paras N.


    We have synthesized core/shell NaGdF4:Nd3+/NaGdF4 nanocrystals with an average size of 15 nm and exceptionally high photoluminescence (PL) quantum yield. When excited at 740 nm, the nanocrystals manifest spectrally distinguished, near infrared to near infrared (NIR-to-NIR) downconversion PL peaked at ~900, ~1050, and ~1300 nm. The absolute quantum yield of NIR-to-NIR PL reached 40% for core-shell nanoparticles dispersed in hexane. Time-resolved PL measurements revealed that this high quantum yield was achieved through suppression of nonradiative recombination originating from surface states and cross relaxations between dopants. NaGdF4:Nd3+/NaGdF4 nanocrystals, synthesized in organic media, were further converted to be water-dispersible by eliminating the capping ligand of oleic acid. NIR-to-NIR PL bioimaging was demonstrated both in vitro and in vivo through visualization of the NIR-to-NIR PL at ~900 nm under incoherent lamp light excitation. The fact that both excitation and the PL of these nanocrystals are in the biological window of optical transparency, combined with their high quantum efficiency, spectral sharpness and photostability, makes these nanocrystals extremely promising as optical biomaging probes. PMID:22401578

  20. Shell Analysis Manual


    loading (e. g. shallow shell theory , Geckeler’s approximation for symmetrically loaded shells, etc.) Although the Shear Deformation and Specialized...interest. Included are the Reissner-Meissner equations, Geckeler’s approximations, shallow - shell theory , Donnell’s theory, and others. A. General Shells of

  1. 基于JSP和Struts2的Web新闻发布系统的设计与开发%Design and Development the Web News Release System Based on JSP and Struts2



    With the rapid development of the Internet, various kinds of news information resources through the database integration, unified management, focus on the release, has become the development direction of news and information release platform. This paper introduces the design of a Java Web development technology, using Struts2 Web framework of general news currently popular developed by the release system. Mainly introduces the functional structure, database design, project news publishing system required Struts2 framework classes and the specific method of database model class.%随着互联网的飞速发展,各种新闻信息资源通过数据库的集成,进行统一管理、集中发布,已成为新闻信息发布平台的发展方向。文章设计了一个基于Java Web开发技术,运用目前受欢迎的Web框架Struts 2所开发的通用新闻发布系统,重点介绍了新闻发布系统的功能结构、数据库设计、项目所需Struts 2框架类以及数据库模型类的具体方法。

  2. Research on Development of Web Applications Based on Struts and Hibernate Framework%基于Struts+Hibernate框架的Web应用开发

    李征; 于建武; 刘镇



  3. Improving way of boiler efficient of shell boiler%提高锅壳燃气锅炉热效率的途径



    Shell boiler is widely adopted recently due to its tight seal performance,accompanied with strict environment pollutant emission standard.Gas fueled boiler has a higher exit flue gas temper-ature(higher than 180 ℃),which lost a lot of energy.This paper,take WNS gas fueled boiler for instance,presents a technique of pre-heater and water vapor condenser to recover this thermal en-ergy.%随着国家对环境保护要求的重视,锅壳燃气锅炉以其环保性能突出的优点被广泛地应用。但是,目前燃气锅炉排烟温度普遍偏高(一般在180℃以上),造成很大的能源浪费已成为亟待解决的问题。本文对提高 WNS 型燃气锅炉利用冷凝器和预热器降低排烟温度,提高热效率作了初步探讨。

  4. Plasmonic enhancement of the optical absorption and catalytic efficiency of BiVO₄ photoanodes decorated with Ag@SiO₂ core-shell nanoparticles.

    Abdi, Fatwa F; Dabirian, Ali; Dam, Bernard; van de Krol, Roel


    Recent progress in the development of bismuth vanadate (BiVO4) photoanodes has firmly established it as a promising material for solar water splitting applications. Performance limitations due to intrinsically poor catalytic activity and slow electron transport have been successfully addressed through the application of water oxidation co-catalysts and novel doping strategies. The next bottleneck to tackle is the modest optical absorption in BiVO4, particularly close to its absorption edge of 2.4 eV. Here, we explore the modification of the BiVO4 surface with Ag@SiO2 core-shell plasmonic nanoparticles. A photocurrent enhancement by a factor of ~2.5 is found under 1 sun illumination (AM1.5). We show that this enhancement consists of two contributions: optical absorption and catalysis. The optical absorption enhancement is induced by the excitation of localized surface plasmon resonances in the Ag nanoparticles, and agrees well with our full-field electromagnetic simulations. Far-field effects (scattering) are found to be dominant, with a smaller contribution from near-field plasmonic enhancement. In addition, a significant catalytic enhancement is observed, which is tentatively attributed to the electrocatalytic activity of the Ag@SiO2 nanoparticles.

  5. Modification of strut effectiveness factor for reinforced concrete deep beams strengthened with CFRP laminates

    Panjehpour, M.


    Full Text Available This paper proposes a method to modify the strut effectiveness factor in the strut-and-tie model for CFRP-strengthened reinforced concrete deep beams. Two groups of deep beams comprising six ordinary reinforced concrete deep beams and six CFRP-strengthened reinforced concrete deep beams were experimentally tested under the four-point bending configuration. The shear span-to-effective depth ratio of the beams in each group was 0.75, 1.00, 1.25, 1.50, 1.75, and 2.00. The theoretical principal tensile strain in CFRP-strengthened struts was modified based on a proposed empirical relationship, based on two ratios: the experimental to the theoretical value of principal tensile strain and the shear span-to-effective depth of deep beams.En este trabajo se propone un método en el que se modifica el factor de eficacia que se aplica a las bielas en el modelo de bielas y tirantes para vigas de canto de hormigón reforzadas con laminados CFRP (polímero reforzado con fibras de carbono. Mediante el ensayo a cuatro puntos se determina la resistencia a flexotracción de doce vigas de canto divididas en dos grupos de seis, las del primer grupo de hormigón armado normal y las del segundo de hormigón reforzado con laminados de CFRP. En ambos grupos cada una de las seis vigas se caracteriza por una relación luz de cortante-canto útil distinta, con valores utilizados de: 0.75, 1.00, 1.25, 1.50, 1.75, y 2.00. El valor teórico de la deformación principal por tracción de la biela reforzada con CFRP se modifica de acuerdo con la relación empírica propuesta en este trabajo. Esta se establece a partir de otras dos: la relación entre los valores experimental y teórico de la deformación por tracción principal y la relación luz de cortante-canto útil de las vigas de canto.

  6. Ultra-thin strut cobalt chromium bare metal stent usage in a complex real-world setting. (SOLSTICE Registry)

    Suttorp, M. J.; Stella, P. R.; Dens, J.; McKenzie, J. M.; Park, K. S.; Frambach, P.


    Aim To report clinical follow-up at 6 months after implantation of the ultra-thin strut cobalt chromiumSolarFlex stent in a real-world setting. Methods and results Patients (n=240) with single or multiple vessel coronary artery disease undergoing percutaneous coronary intervention (PCI) at four site

  7. Automated stent strut coverage and apposition analysis of in-vivo intra coronary optical coherence tomography images

    Ughi, Giovanni J.; Adriaenssens, Tom; Onsea, Kevin; Kayaert, Peter; Dubois, Christophe; Coosemans, Mark; Sinnaeve, Peter; Desmet, Walter; D'hooge, Jan


    Several studies have proven that intra-vascular OCT is an appropriate imaging modality able to evaluate stent strut apposition and coverage in coronary arteries. Currently image processing is performed manually resulting in a very time consuming and labor intensive procedure. We propose an algorithm for fully automatic individual stent strut apposition and coverage analysis in coronary arteries. The vessel lumen and stent strut are automatically detected and segmented through analysis of the intensity profiles of the A-scan lines. From these data, apposition and coverage can then be estimated automatically. The algorithm was validated using manual measurement (performed by two trained cardiologists) as a reference. 108 images were taken at random from in-vivo pullbacks from 9 different patient presenting 'real-life' situations (i.e. blood residual, small luminal objects and artifacts). High Pearson's correlation coefficients were found (R = 0.96 - 0.95) between the automated and manual measurements while Bland-Altman statistics showed no significant bias with good limits of agreement. As such, it was shown that the presented algorithm provides a robust and a fast tool to automatically estimate apposition and coverage of stent struts in in-vivo pullbacks. This will be important for the integration of this technology in clinical routine and large clinical trials.

  8. Ultimate Load Capacity and Behavior of Thin-Walled Curved-Steel Square Struts, Subjected to Compressive Load

    S.Mohammad Reza Mortazavi


    Full Text Available There have been some experimental tests on hollow curved-steel struts with thin-walled square sections, in order to investigate their general behavior, particularly their capacity for bearing differing loads. One set of square tubes are cold-formed into segments of circular arcs with curvature radii, equal to 4000 mm. Different lengths of curved struts are fabricated so as to cover a practical range of slenderness ratios. The struts tests were pin-ended and had slenderness ratios, based on the straight length between ends ranging from 31-126. The cold-forming operation induces initial inelastic behavior and associated residual stresses. There is, therefore, an interaction among material effects, such as the strain hardening capacity, the Bauschinger effect, strain aging, and residual stresses, together with the significant geometrical effect of the initial curvature, caused by the cold-forming operation. Eventually the results from three series of tests, which are taken on fully-aged and stress-relief-annealed square curved struts, are compared. The variations in load carrying response are discussed.

  9. Automated detection of vessel lumen and stent struts in intravascular optical coherence tomography to evaluate stent apposition and neointimal coverage

    Nam, Hyeong Soo; Kim, Chang-Soo; Yoo, Hongki, E-mail:, E-mail: [Department of Biomedical Engineering, Hanyang University, Seoul 04763 (Korea, Republic of); Lee, Jae Joong; Song, Joon Woo; Kim, Jin Won, E-mail:, E-mail: [Division of Interventional Cardiology, Cardiovascular Center, Korea University Guro Hospital, Seoul 08308 (Korea, Republic of)


    Purpose: Intravascular optical coherence tomography (IV-OCT) is a high-resolution imaging method used to visualize the microstructure of arterial walls in vivo. IV-OCT enables the clinician to clearly observe and accurately measure stent apposition and neointimal coverage of coronary stents, which are associated with side effects such as in-stent thrombosis. In this study, the authors present an algorithm for quantifying stent apposition and neointimal coverage by automatically detecting lumen contours and stent struts in IV-OCT images. Methods: The algorithm utilizes OCT intensity images and their first and second gradient images along the axial direction to detect lumen contours and stent strut candidates. These stent strut candidates are classified into true and false stent struts based on their features, using an artificial neural network with one hidden layer and ten nodes. After segmentation, either the protrusion distance (PD) or neointimal thickness (NT) for each strut is measured automatically. In randomly selected image sets covering a large variety of clinical scenarios, the results of the algorithm were compared to those of manual segmentation by IV-OCT readers. Results: Stent strut detection showed a 96.5% positive predictive value and a 92.9% true positive rate. In addition, case-by-case validation also showed comparable accuracy for most cases. High correlation coefficients (R > 0.99) were observed for PD and NT between the algorithmic and the manual results, showing little bias (0.20 and 0.46 μm, respectively) and a narrow range of limits of agreement (36 and 54 μm, respectively). In addition, the algorithm worked well in various clinical scenarios and even in cases with a low level of stent malapposition and neointimal coverage. Conclusions: The presented automatic algorithm enables robust and fast detection of lumen contours and stent struts and provides quantitative measurements of PD and NT. In addition, the algorithm was validated using

  10. MVC Design Pattern for the multi framework distributed applications using XML, spring and struts framework

    Praveen Gupta,


    Full Text Available The model view controller (MVC is a fundamental design pattern for the separation between user interface logic and business logic. Since applications are very large in size these days and the MVC designpattern can weak the coupling among the different application tiers of application. this paper presents a web application framework based on MVC in J2EE platform, and extends it with XML so that the framework is more flexible, expansible and easy to maintain. This is a multi tier system including presentation layer, business layer, data persistence layer and database layer. This separate codes, and improve maintainability and reusability of the application. In this paper, we implemented MVC using spring and struts framework. Our research study show that applying multiple framework to design theapplications using MVC concepts makes applications easier compare to a single framework.

  11. Highly efficient perovskite solar cells based on a nanostructured WO3-TiO2 core-shell electron transporting material

    Mahmood, Khalid


    Until recently, only mesoporous TiO2 and ZnO were successfully demonstrated as electron transport layers (ETL) alongside the reports of ZrO2 and Al2O3 as scaffold materials in organometal halide perovskite solar cells, largely owing to ease of processing and to high power conversion efficiency. In this article, we explore tungsten trioxide (WO3)-based nanostructured and porous ETL materials directly grown hydrothermally with different morphologies such as nanoparticles, nanorods and nanosheet arrays. The nanostructure morphology strongly influences the photocurrent and efficiency in organometal halide perovskite solar cells. We find that the perovskite solar cells based on WO3 nanosheet arrays yield significantly enhanced photovoltaic performance as compared to nanoparticles and nanorod arrays due to good perovskite absorber infiltration in the porous scaffold and more rapid carrier transport. We further demonstrate that treating the WO3 nanostructures with an aqueous solution of TiCl4 reduces charge recombination at the perovskite/WO3 interface, resulting in the highest power conversion efficiency of 11.24% for devices based on WO3 nanosheet arrays. The successful demonstration of alternative ETL materials and nanostructures based on WO3 will open up new opportunities in the development of highly efficient perovskite solar cells. This journal is © The Royal Society of Chemistry 2015.

  12. Long-term results of anterior cervical corpectomy and fusion with nano-hydroxyapatite/polyamide 66 strut for cervical spondylotic myelopathy

    Zhang, Yuan; Deng, Xu; Jiang, Dianming; Luo, Xiaoji; Tang, Ke; Zhao, Zenghui; Zhong, Weiyang; Lei, Tao; Quan, Zhengxue


    To assess the long-term clinical and radiographic outcomes of anterior cervical corpectomy and fusion (ACCF) with a neotype nano-hydroxyapatite/polyamide 66 (n-HA/PA66) strut in the treatment of cervical spondylotic myelopathy (CSM). Fifty patients with CSM who underwent 1- or 2-level ACCF with n-HA/PA66 struts were retrospectively investigated. With a mean follow-up of 79.6 months, the overall mean JOA score, VAS and cervical alignment were improved significantly. At last follow-up, the fusion rate was 98%, and the subsidence rate of the n-HA/PA66 strut was 8%. The “radiolucent gap” at the interface between the n-HA/PA66 strut and the vertebra was further noted to evaluate the osteoconductivity and osseointegration of the strut, and the incidence of it was 62% at the last follow-up. Three patients suffered symptomatic adjacent segment degeneration (ASD). No significant difference was detected in the outcomes between 1- and 2-level corpectomy at follow-ups. In conclusion, the satisfactory outcomes in this study indicated that the n-HA/PA66 strut was an effective graft for cervical reconstruction. Moreover, the osteoconductivity and osseointegration of the strut is still need to be optimized for future clinical application owing to the notably presence of “radiolucent gap” in present study.

  13. Free fibular strut graft in neglected femoral neck fractures in adult

    Azam Md Quamar


    Full Text Available Background: Neglected femoral neck fracture in adults still poses a formidable challenge. Existing treatment options varies from osteotomy (with or without graft to osteosynthesis using various implants and grafting techniques (muscle pedicle, vascularized, and nonvascularized fibula. The aim of this study was to assess outcome of nonvascularized fibular strut graft and cancellous screw fixation in neglected femoral neck fractures in the younger age group. Materials and Methods: Medical records of 32 patients of neglected femoral neck fracture, in the age group of 22-45 years (mean 37.8 years, operated between May 1994 to December 2001, were retrospectively reviewed. After the application of inclusion and exclusion criteria, 28 patients having three years minimum follow-up (mean 4.6 years were included. Delay between injury and operation varied from four weeks to 42 weeks (mean 16.4 weeks. Closed reduction was achieved in 17 patients; open reduction through Watson-Jones anterolateral approach was performed in the remaining 15 patients in whom closed reduction failed. The fracture was transfixed with three parallel guide wires. Appropriate sized cannulated lag screw (7 mm was then inserted in two of the wires. Selection of the third guide wire for fibula depended on the space available in both anteroposterior and lateral view. Results: Satisfactory bony union was obtained in 25 patients, of whom in four cases, the union occurred in 10-20° (mean 15° of varus. Nonunion occurred in three patients (9.37%, and aseptic necrosis occurred in another six patients (18.75%. Of the 25 patients where union was achieved, five patients showed excellent results; 14 good and six had poor functional result, as evaluated using modified Anglen criteria. Conclusion: Nonvascularized fibular strut graft along with cancellous screws provides a dependable and technically less-demanding alternative procedure for neglected femoral neck fractures in young adults. Fibula

  14. Multiple shells in IRC+10216: shell properties

    Mauron, N.; Huggins, P. J.


    We report on the properties of the multiple shells in the circumstellar envelope of IRC+10216, using deep optical imaging, including data from the Hubble Space Telescope. The intensity profiles confirm the presence of thin ( ~ 0farcs5 -3'' ec), limb-brightened shells in the envelope, seen in stellar and ambient Galactic light scattered by dust. The shells are spaced at irregular intervals of ~ 5'' ec-20'' ec, corresponding to time scales of 200-800 yr, although intervals as short as ~ 1'' ec (40 yr) are seen close to the star. The location of the main shells shows a good correlation with high-resolution, molecular line maps of the inner envelope, indicating that the dust and gas are well coupled. The shell/intershell density contrast is typically ~ 3, and we find that the shells form the dominant mass component of the circumstellar envelope. The shells exhibit important evolutionary effects: the thickness increases with increasing radius, with an effective dispersion velocity of 0.7 km s-1 and there is evidence for shell interactions. Despite the presence of bipolar structure close to the star, the global shell pattern favors a roughly isotropic, episodic mass loss mechanism, with a range of time scales. Based on observations made with the Canada-France-Hawaii telescope, operated by CNRS, NRCC and UH, and on dearchived observations made with the NASA/ESA Hubble Space Telescope, operated by AURA Inc., under NASA contract NAS5-26555

  15. Au/SiO2/QD core/shell/shell nanostructures with plasmonic-enhanced photoluminescence

    Yang, Ping; Kawasaki, Kazunori; Ando, Masanori; Murase, Norio


    A sol-gel method has been developed to fabricate Au/SiO2/quantum dot (QD) core-shell-shell nanostructures with plasmonic-enhanced photoluminescence (PL). Au nanoparticle (NP) was homogeneously coated with a SiO2 shell with adjusted thickness through a Stöber synthesis. When the toluene solution of hydrophobic CdSe/ZnS QDs was mixed with partially hydrolyzed 3-aminopropyltrimethoxysilane (APS) sol, the ligands on the QDs were replaced by a thin functional SiO2 layer because the amino group in partially hydrolyzed APS has strong binding interaction with the QDs. Partially hydrolyzed APS plays an important role as a thin functional layer for the transfers of QDs to water phase and the subsequent connection to aqueous SiO2-coated Au NPs. Although Au NPs were demonstrated as efficient PL quenchers when the SiO2 shell on the Au NPs is thin (less than 5 nm), we found that precise control of the spacing between the Au NP core and the QD shell resulted in QDs with an enhancement of 30 % of PL efficiency. The Au/SiO2/QD core/shell/shell nanostructures also reveal strong surface plasmon scattering, which makes the Au/SiO/QD core-shell-shell nanostructures an excellent dual-modality imaging probe. This technology can serve as a general route for encapsulating a variety of discrete nanomaterials because monodispersed nanostructures often have a similar surface chemistry.

  16. Fabrication of Pd Nanoparticles Embedded C@Fe3O4 Core-Shell Hybrid Nanospheres: An Efficient Catalyst for Cyanation in Aryl Halides.

    Suresh Kumar, Basuvaraj; Amali, Arlin Jose; Pitchumani, Kasi


    Isolated chemical reactors were fabricated by integrating catalytically active sites (Pd) with magnetic functionality (Fe3O4) along with carbon while preserving the constituents functional properties to realize the structure-property relationship of Pd by comparing the catalytic activity of spherical Pd NPs with cubical Pd NPs for cyanation in aryl halides using K4[Fe(CN)6] as a green cyanating agent to yield corresponding nitriles. The superior catalytic reactivity of the cubical Pd NPs is attributed to the larger number of {100} surface facets. The TEM images of reused catalyst shows the change in structure from cubical to spherical nanoparticles, attributed to the efficient leaching susceptibility of Pd {100} surface facets. The cubical Pd NPs on carbon@Fe3O4 is attractive in view of its high catalytic efficiency, easy synthesis, magnetic separability, environmental friendliness, high stability, gram scale applicability, and reusability.

  17. Fast and efficient removal of silver (I) from aqueous solutions using aloe vera shell ash supported Ni0.5Zn0.5Fe2O4 magnetic nanoparticles



    Silver (I) was removed from aqueous environment by aloe vera shell ash supported Ni0.5Zn0.5Fe2O4 magnetic nanoparticles. The adsorbent was characterized by several methods including X-ray diffraction (XRD), scanning electron microscopy (SEM), BET isotherm, vibrating sample magnetometer (VSM) and Fourier transform infrared spectroscopy (FT-IR). To determine the absorption of silver (I) by this adsorbent, different pH values (2−7), adsorbent dose (0.01−0.5 g), concentrations of Ag+(50, 100, 200, 300, 500, 700 and 1000 mg/L) and exposure time (5−100 min) were experimented. The highest removal efficiency of Ag+was achieved under optimum condition (30 min and pH=5). The optimum adsorbent dose was 0.20 g (in 50 mL of 100 mg/L Ag+ solution), which achieved a removal efficiency of 98.3%. The maximum monolayer adsorption capacity based on the Langmuir isotherm is 243.90 mg/g. Characterization results revealed that specific surface area and porous volume were 814.23 m2/g and 0.726 cm3/g, respectively. The experimental data were fitted well with the Langmuir and Freundlich isotherm models. Synthesized adsorbent has desired surface area and adsorptive capacity for silver (I) adsorption in aquatic environment.

  18. Removal of silver nanoparticles by mussel-inspired Fe3O4@ polydopamine core-shell microspheres and its use as efficient catalyst for methylene blue reduction

    Maoling Wu; Yinying Li; Rui Yue; Xiaodan Zhang; Yuming Huang


    The removal of silver nanoparticles (AgNPs) from water is highly needed because of their increasing use and potential risk to the environment due to their toxic effects. Catalysis over AgNPs has received significant attention because of their highly catalytic performance. However, their use in practical applications is limited due to high cost and limited resources. Here, we present for the first time that the mussel-inspired Fe3O4@polydopamine (Fe3O4@PDA) nanocomposite can be used for effici...

  19. Paraboloid Shell As Footing

    Al Ansari, Mohammed S.


    A simplified method for the design of paraboloid shell footing base on the displacement of the shell's crown where the column axial load is transferred to the footing has been developed. A case study was presented to demonstrate the use of the proposed method and to illustrate its capabilities. The results of the proposed method confirm the ability of the shell model in determining accurate and practical results for the design of paraboloid shell footing. Base on the analytical results of thi...

  20. Orthotropic rotation-free thin shell elements

    Munglani, Gautam; Wittel, Falk K; Herrmann, Hans J


    A method to simulate orthotropic behaviour in thin shell finite elements is proposed. The approach is based on the transformation of shape function derivatives, resulting in a new orthogonal basis aligned to a specified preferred direction for all elements. This transformation is carried out solely in the undeformed state leaving minimal additional impact on the computational effort expended to simulate orthotropic materials compared to isotropic, resulting in a straightforward and highly efficient implementation. This method is implemented for rotation-free triangular shells using the finite element framework built on the Kirchhoff--Love theory employing subdivision surfaces. The accuracy of this approach is demonstrated using the deformation of a pinched hemispherical shell (with a 18{\\deg} hole) standard benchmark. To showcase the efficiency of this implementation, the wrinkling of orthotropic sheets under shear displacement is analyzed. It is found that orthotropic subdivision shells are able to capture t...


    Wei Fayuan; Li Shiqi; Zhong Yifang; Huang Yuying


    The dynamic behaviors of rotating shells coupled with liquid are shown. The shell under consideration has arbitrary boundary conditions and a complex shape. A modified boundary element method and finite strip technique are used to improve the computing efficiency and to guarantee the continuity conditions on the liquid-shell interaction plane. The effects of various parameters such as shell's thickness and liquid depth are investigated. Dynamic simulations are applied to several typical shell-liquid systems, and the natural frequencies, mode shapes and response of vibration are calculated numerically.

  2. The Numerical Simulation Analysis on Heat Transfer Efficiency Influence Factors of Shell and Tube Heat Exchanger%管壳式换热器传热效率影响因素及数值模拟分析∗

    王庆锋; 庞鑫; 赵双


    多数管壳式换热器基于传统的经验设计方法,换热器质量大且能耗高。鉴于此,采用Fluent仿真模拟的方法,研究了换热管类型、折流板间距、折流板切率变化与换热器对流传热系数的关系,并用HTFS工程软件进行了模型验证。研究结果表明,采用特型管(如波节管和波纹管等)代替光管,可以增强管内流体扰动,提高湍流程度,增大管程对流传热系数,但同时也增大了压降;折流板间距越大,壳程对流传热系数越小,压降也越小,当折流板间距为330 mm时,换热器最高效,此时换热器在较小的压降下可以获得较大的对流传热系数;折流板切率越大,压降越小,当管束错流流速与折流窗口流速相等时,壳程对流传热系数最大,折流板切率35%为最优值,换热器效率最高。最后提出了管壳式换热器优化设计方法,将优化设计的换热器用于某化肥厂氮氢气压缩机级间冷却,同等热负荷条件下换热面积减小了21�37%。研究结果为换热器的结构参数优化提供了依据。%Most of shell and tube heat exchanger design based on traditional experiences have the issues of high weight and high energy consumption�The effects of heat transfer tube types, baffle spacing, and baffle plate cut rate on the heat exchanger convective heat transfer coefficient have been studied by suing fluent simulation method�The model is validated by HTFS engineering software�The results showed that the alternative special⁃shaped tube for the smooth tube, like the corrugated tube and bellows, could enhance fluid disturbances and the turbu⁃lence level, increase the tube convective heat transfer coefficient, but also increases the pressure drop�Increase the baffle plate spacing will decrease the shell side convective heat transfer coefficient and the pressure drop�The heat exchanger is the most efficient when the baffle plate

  3. Efficient C-O and C-N bond forming cross-coupling reactions catalyzed by core-shell structured Cu/Cu2O nanowires

    Elshewy, Ahmed M.


    Oxygen and Nitrogen containing compounds are of utmost importance due to their interesting and diverse biological activities. The construction of the C-O and C–N bonds is of significance as it opens avenues for the introduction of ether and amine linkages in organic molecules. Despite significant advancements in this field, the construction of C-O and C–N bonds is still a major challenge for organic chemists, due to the involvement of harsh reaction conditions or the use of expensive catalysts or ligands in many cases. Thus, it is a challenge to develop alternative, milder, cheaper and more reproducible methodologies for the construction of these types of bonds. Herein, we introduce a new efficient ligand free catalytic system for C-O and C-N bond formation reactions.

  4. Yolk–shell Fe3O4@SiO2@PMO: amphiphilic magnetic nanocomposites as an adsorbent and a catalyst with high efficiency and recyclability

    Dai, Jinyu


    This study describes the preparation of a multifunctional adsorptive catalyst by the incorporation of ligand groups within the channels of magnetic amphiphilic nanocomposites and attached with Pd nanoparticles. It was clearly demonstrated that Pd2+ was adsorbed by ligand-functionalized materials in water, and then Pd2+ was coordinated with ligand groups. Finally, the Pd nanoparticles were produced via an in situ reduction of Pd2+ by ligand groups through a simple hydrothermal process. Moreover, amphiphilic nanomaterials are viewed as excellent collectors of hydrophobic contaminants in water. The immobilized catalytic active sites with ligand-functionalized nanocomposites were allowed for maximal exposure to the reactants with minimal leaching of the Pd nanoparticles. The unique amphiphilic nanocomposites enabled selective oxidation of alcohols to proceed efficiently in water under aerobic conditions. Moreover, this nanocomposite catalyst could be completely recovered using an external magnet due to the superparamagnetic behavior of Fe3O4 and can be recycled with sustained selectivity and activity.

  5. Removal of silver nanoparticles by mussel-inspired Fe3O4@ polydopamine core-shell microspheres and its use as efficient catalyst for methylene blue reduction

    Wu, Maoling; Li, Yinying; Yue, Rui; Zhang, Xiaodan; Huang, Yuming


    The removal of silver nanoparticles (AgNPs) from water is highly needed because of their increasing use and potential risk to the environment due to their toxic effects. Catalysis over AgNPs has received significant attention because of their highly catalytic performance. However, their use in practical applications is limited due to high cost and limited resources. Here, we present for the first time that the mussel-inspired Fe3O4@polydopamine (Fe3O4@PDA) nanocomposite can be used for efficient removal and recovery of AgNPs. Adsorption of AgNPs over Fe3O4@PDA was confirmed by TEM, FT-IR, XRD, TGA and magnetic property. The adsorption efficiency of AgNPs by Fe3O4@PDA was investigated as a function of pH, contact time, ionic strength and concentration of AgNPs. The kinetic data were well fitted to a pseudo-second order kinetic model. The isotherm data were well described by Langmuir model with a maximum adsorption capacity of 169.5 mg/g, which was higher than those by other adsorbents. Notably, the obtained AgNPs-Fe3O4@PDA exhibited highly catalytic activity for methylene blue reduction by NaBH4 with a rate constant of 1.44 × 10‑3/s, which was much higher than those by other AgNPs catalysts. The AgNPs-Fe3O4@PDA promised good recyclability for at least 8 cycles and acid resistant with good stability.

  6. Removal of silver nanoparticles by mussel-inspired Fe3O4@ polydopamine core-shell microspheres and its use as efficient catalyst for methylene blue reduction

    Wu, Maoling; Li, Yinying; Yue, Rui; Zhang, Xiaodan; Huang, Yuming


    The removal of silver nanoparticles (AgNPs) from water is highly needed because of their increasing use and potential risk to the environment due to their toxic effects. Catalysis over AgNPs has received significant attention because of their highly catalytic performance. However, their use in practical applications is limited due to high cost and limited resources. Here, we present for the first time that the mussel-inspired Fe3O4@polydopamine (Fe3O4@PDA) nanocomposite can be used for efficient removal and recovery of AgNPs. Adsorption of AgNPs over Fe3O4@PDA was confirmed by TEM, FT-IR, XRD, TGA and magnetic property. The adsorption efficiency of AgNPs by Fe3O4@PDA was investigated as a function of pH, contact time, ionic strength and concentration of AgNPs. The kinetic data were well fitted to a pseudo-second order kinetic model. The isotherm data were well described by Langmuir model with a maximum adsorption capacity of 169.5 mg/g, which was higher than those by other adsorbents. Notably, the obtained AgNPs-Fe3O4@PDA exhibited highly catalytic activity for methylene blue reduction by NaBH4 with a rate constant of 1.44 × 10−3/s, which was much higher than those by other AgNPs catalysts. The AgNPs-Fe3O4@PDA promised good recyclability for at least 8 cycles and acid resistant with good stability. PMID:28202922

  7. Numerical optimization on supersonic combustor using ethylene with strut and cavity combination%乙烯超燃燃烧室支板/凹腔结构组合数值优化

    王应洋; 李旭昌; 吴振亚; 杨发煜


    The numerical simulation based on the finite volume method of combustor with an ethylene equivalence ratio of 0.6 was carried out to investigate the flow field characteristics of supersonic combustor patterns with alternating-wedge strut. The impacts of different arrangements for injectors, different numbers of alternating-wedge structures of strut and different upswept angles on mix-ing efficiency and total pressure loss were considered. The result shows that more injectors will lead to better mixing effect of air with fuel, whereas too many injectors will reduce the penetration depth and lead to the lapping of fuel plume area which goes against the mixing efficiency. More alternating-wedge structures lead to stronger stream wise vortices, but the mixing efficiency of farther region is not ideal and high mixing efficiency can be obtained near the cavity by four rears. To some degree, the bigger the upswept angle is, the higher the mixing efficiency will be and tapered rear strut is also in favor of enhancing the mixing effect, however both of them will result in more total pressure loss.%为探索带交错尾部支板的超燃燃烧室流场特性,运用有限体积法对乙烯喷注当量比0.6的燃烧室进行了数值模拟. 对比喷孔不同布置方式,支板尾部交错结构不同数目、不同翘角对混合效率、总压损失的影响. 研究发现,喷孔数目越多,对燃料与空气充分混合越有利,但过多喷孔会降低穿透深度,且导致可燃混合区重叠,不利于掺混增强;交错结构数目越多,产生的流向涡涡量强度越大,但远场混合效率并不理想,当支板交错结构数目等于4时,在凹腔附近能取得较大掺混效率;在一定范围内,支板翘角越大,掺混效果越好,交错结构掠形尾部也有利于掺混增强,但均会导致更大的总压损失.

  8. Comparative analysis of the influence between Hiper Strut and Macpherson suspension on vehicle handling stability%Hiper Strut 悬架与 Macpherson 悬架对整车操稳的影响对比分析

    秦玉英; 孙明浩; 王金; 侯志国; 桂军


    Hiper Strut suspension is an improved Macpherson suspension .To comparative the influence between them on vehicle handling stability ,a Hiper Strut front suspension for a domestic SUV was designed according to a Macpherson suspension which was used as a front suspension for the same SUV .Two SUV models with different front suspensions but same vehicle parameters were established based on Adams/Car.The result of simulation tests shows that Hiper Strut suspension is better than Macpherson suspension on vehicle handling stability .%Hiper Strut悬架是由Macpherson悬架改进而来,为比较两者对整车操纵稳定性的影响,根据一款国产运动型多用途汽车( Sport Utility Vehicle ,SUV)的Macpherson前悬架,设计出适用于该车的Hiper Strut前悬架,保持整车参数不变,利用Adams/Car软件分别建立原型车和改型车的整车模型,通过仿真试验,分析对比两种悬架在整车操纵稳定性上的表现。试验结果表明,Hiper Strut悬架综合性能优于Macpherson悬架。

  9. 基于Struts-Hibernate构架的数字化教学评估档案管理系统%Digitized archives management system for teaching evaluation based on struts-hibernate architecture

    郭广军; 徐章法; 羊四清


    给出了基于Struts-Hibernate的Java EE整合架构,剖析了Struts-Hibernate整合原理和关键技术.根据本科教学评估指标体系,设计并实现了一个跨平台的数字化教学评估档案管理系统(DAMS4TE).该系统实现了数字化教学评估档案的上传、下栽、修改、删除,查询和分类等管理功能.Struts-Hibernate架构降低了系统的耦合度,提高了系统的可移值性、可扩展性和安全性,在可扩展的企业级应用开发中有很好的前景.实验结果表明,DAMS4TE规范了教学评估档案建设,提高了工作效率.

  10. Structural FEM analysis of the strut-to-fuselage joint of a two-seat composite aircraft

    Vargas-Rojas, Erik, E-mail:; Camarena-Arellano, Diego, E-mail:; Hernández-Moreno, Hilario, E-mail: [IPN, ESIME Ticomán, Av. Ticomán 600, Col. San José Ticomán 07340 (Mexico)


    An analysis of a strut-to-fuselage joint is realized in order to evaluate the zones with a high probability of failure by means of a safety factor. The whole section is analyzed using the Finite Element Method (FEM) so as to estimate static resistance behavior, therefore it is necessary a numerical mock-up of the section, the mechanical properties of the Carbon-Epoxy (C-Ep) material, and to evaluate the applied loads. Results of the analysis show that the zones with higher probability of failure are found around the wing strut and the fuselage joint, with a safety factor lower than expected in comparison with the average safety factor used on aircrafts built mostly with metals.

  11. Ununited fracture neck of femur treated with closed reduction and internal fixation with cancellous screw and fibular strut graft

    Singh Daria


    Full Text Available Background: Ununited fracture neck of femur in young adults has been tackled in various ways. Methods: Twenty five patients of ununited fracture neck of femur in age group 21-55 years were treated by closed reduction, cancellous screw fixation and fibular strut graft and followed up for 2-6 years. Time gap between injury and operation was 6 weeks to 58 weeks. Five cases were previously fixed with various fixation devices. Results: Osseous union was achieved in 24 cases with average time of 18.16 weeks. Main complication encountered in follow-up was avascular necrosis of femoral head, others were joint stiffness and shortening. Functional end results were good to excellent in 24 cases. Conclusion: Closed reduction with internal fixation by cancellous screw and fibular strut grafting is easy and useful procedure.

  12. Multibody dynamics modelling and system identification of a quarter-car test rig with McPherson strut suspension

    Sandu, Corina; Andersen, Erik R.; Southward, Steve


    In this paper, we develop a multibody dynamics model of a quarter-car test-rig equipped with a McPherson strut suspension and we apply a system identification technique on it. Constrained equations of motion in the Lagrange multiplier form are derived and employed to characterise the dynamic behaviour of the test rig modelled once as a linear system and once as a non-linear system. The system of differential algebraic equations is integrated using a Hilber-Hughes-Taylor integrator. The responses of both models (linear and non-linear) to a given displacement input are obtained and compared with the experimental response recorded using the physical quarter-car test rig equipped with a McPherson strut suspension. The system identification is performed for control purposes. The results, as well as the performance and area of applicability of the test rig models derived, are discussed.

  13. Structural FEM analysis of the strut-to-fuselage joint of a two-seat composite aircraft

    Vargas-Rojas, Erik; Camarena-Arellano, Diego; Hernández-Moreno, Hilario


    An analysis of a strut-to-fuselage joint is realized in order to evaluate the zones with a high probability of failure by means of a safety factor. The whole section is analyzed using the Finite Element Method (FEM) so as to estimate static resistance behavior, therefore it is necessary a numerical mock-up of the section, the mechanical properties of the Carbon-Epoxy (C-Ep) material, and to evaluate the applied loads. Results of the analysis show that the zones with higher probability of failure are found around the wing strut and the fuselage joint, with a safety factor lower than expected in comparison with the average safety factor used on aircrafts built mostly with metals.

  14. Fractured inferior vena cava filter strut presenting as a penetrating foreign body in the right ventricle: report of a case.

    Kumar, S Prathap; Mahtabifard, Ali; Young, J Nilas


    Migration of a fractured strut of an inferior vena cava (IVC) filter to the heart is a rare complication. We report the case of a 40-year-old woman who had this complication eight months after infrarenal IVC filter placement. She presented with chest pain. The broken arm of the IVC filter had migrated to the heart and penetrated the free wall of the right ventricle. It was removed successfully by cardiac surgery without the aid of cardiopulmonary bypass.

  15. Highly efficient and recyclable triple-shelled Ag@Fe3O4@SiO2@TiO2 photocatalysts for degradation of organic pollutants and reduction of hexavalent chromium ions

    Su, Jianwei; Zhang, Yunxia; Xu, Sichao; Wang, Shuan; Ding, Hualin; Pan, Shusheng; Wang, Guozhong; Li, Guanghai; Zhao, Huijun


    Herein, we demonstrate the design and fabrication of the well-defined triple-shelled Ag@Fe3O4@SiO2@TiO2 nanospheres with burr-shaped hierarchical structures, in which the multiple distinct functional components are integrated wonderfully into a single nanostructure. In comparison with commercial TiO2 (P25), pure TiO2 microspheres, Fe3O4@SiO2@TiO2 and annealed Ag@Fe3O4@SiO2@TiO2 nanocomposites, the as-obtained amorphous triple-shelled Ag@Fe3O4@SiO2@TiO2 hierarchical nanospheres exhibit a markedly enhanced visible light or sunlight photocatalytic activity towards the photodegradation of methylene blue and photoreduction of hexavalent chromium ions in wastewater. The outstanding photocatalytic activities of the plasmonic photocatalyst are mainly due to the enhanced light harvesting, reduced transport paths for both mass and charge transport, reduced recombination probability of photogenerated electrons/holes, near field electromagnetic enhancement and efficient scattering from the plasmonic nanostructure, increased surface-to-volume ratio and active sites in three dimensional (3D) hierarchical porous nanostructures, and improved photo/chemical stability. More importantly, the hierarchical nanostructured Ag@Fe3O4@SiO2@TiO2 photocatalysts could be easily collected and separated by applying an external magnetic field and reused at least five times without any appreciable reduction in photocatalytic efficiency. The enhanced photocatalytic activity and excellent chemical stability, in combination with the magnetic recyclability, make these multifunctional nanostructures promising candidates to remediate aquatic contaminants and meet the demands of future environmental issues.Herein, we demonstrate the design and fabrication of the well-defined triple-shelled Ag@Fe3O4@SiO2@TiO2 nanospheres with burr-shaped hierarchical structures, in which the multiple distinct functional components are integrated wonderfully into a single nanostructure. In comparison with commercial TiO2

  16. Efficiently Enhancing Visible Light Photocatalytic Activity of Faceted TiO2 Nanocrystals by Synergistic Effects of Core-Shell Structured Au@CdS Nanoparticles and Their Selective Deposition.

    Tong, Ruifeng; Liu, Chang; Xu, Zhenkai; Kuang, Qin; Xie, Zhaoxiong; Zheng, Lansun


    Integrating wide bandgap semiconductor photocatalysts with visible-light-active inorganic nanoparticles (such as Au and CdS) as sensitizers is one of the most efficient methods to improve their photocatalytic activity in the visible light region. However, as for all such composite photocatalysts, a rational design and precise control over their architecture is often required to achieve optimal performance. Herein, a new TiO2-based ternary composite photocatalyst with superior visible light activity was designed and synthesized. In this composite photocatalyst, the location of the visible light sensitizers was engineered according to the intrinsic facet-induced effect of well-faceted TiO2 nanocrystals on the spatial separation of photogenerated carriers. Experimentally, core-shell structured Au@CdS nanoparticles acting as visible light sensitizers were selectively deposited onto photoreductive {101} facets of well-faceted anatase TiO2 nanocrystals through a two-step in situ photodeposition route. Because the combination of Au@CdS and specific {101} facets of TiO2 nanocrystals facilitates the transport of charges photogenerated under visible light irradiation, this well-designed ternary composite photocatalyst exhibited superior activity in visible-light-driven photocatalytic H2 evolution, as expected.

  17. A novel quasi-zero-stiffness strut and its applications in six-degree-of-freedom vibration isolation platform

    Zhou, Jiaxi; Xiao, Qingyu; Xu, Daolin; Ouyang, Huajiang; Li, Yingli


    Generally, existing isolators with quasi-zero stiffness (QZS) are designed for mitigating transmission of vertical translational excitations, but vibration isolation in multiple directions is much more desirable and useful. The major contribution of this paper is extending the QZS vibration isolation method from one degree of freedom (DOF) to all six DOFs, by using a novel QZS strut to construct a 6-DOF QZS vibration isolation platform. Firstly, the design concept of the QZS strut is proposed, and then a pyramidal 3-QZS-strut isolator is assembled. Finally, a 6-DOF QZS platform is achieved by using such isolators as supporting mounts. The equations of motion of this platform are established, and solved by the Harmonic Balance method to obtain amplitude-frequency relationships. Moreover, the performance of vibration isolation is evaluated in terms of force/moment transmissibility. Compared with the linear counterpart, the 6-DOF QZS platform has broader bandwidth of vibration isolation starting from lower frequency, and possesses higher effectiveness in low-frequency range, most importantly, in all six DOFs.

  18. A 2-collinear-DoF strut with embedded negative-resistance electromagnetic shunt dampers for spacecraft micro-vibration

    Stabile, Alessandro; Aglietti, Guglielmo S.; Richardson, Guy; Smet, Geert


    Micro-vibration on board a spacecraft is an important issue that affects payloads requiring high pointing accuracy. Although isolators have been extensively studied and implemented to tackle this issue, their application is far from being ideal due to the several drawbacks that they present, such as limited low-frequency attenuation for passive systems or high power consumption and reliability issues for active systems. In the present study, a novel 2-collinear-DoF strut with embedded electromagnetic shunt dampers (EMSD) is modelled, analysed and the concept is physically tested. The combination of high-inductance components and negative-resistance circuits is used in the two shunt circuits to improve the EMSD micro-vibration mitigation and to achieve an overall strut damping performance that is characterised by the elimination of the resonance peaks and a remarkable FRF final decay rate of ‑80 dB dec–1. The EMSD operates without requiring any control algorithm and can be comfortably integrated on a satellite due to the low power required, the simplified electronics and the small mass. This work demonstrates, both analytically and experimentally, that the proposed strut is capable of producing better isolation performance than other well-established damping solutions over the whole temperature range of interest.

  19. A simple expression for the normal spectral emittance of open-cell foams composed of optically thick and smooth struts

    Guévelou, Simon; Rousseau, Benoit; Domingues, Gilberto; Vicente, Jérôme


    A set of 96 open-cell foams with growing porosities (0.35-0.95) and growing pore nominal diameters (0.4-2.6 mm) was artificially generated to firmly connect their normal spectral emittances to their textural features. This work is strictly focused on foams that are composed of opaque struts with optically smooth surfaces. To compute the normal spectral emittances, a Monte Carlo Ray Tracing code was carefully used through an indirect method based on Kirchhoff's laws. The Monte Carlo Ray Tracing code considers the complex refractive index of the solid phase constituting the struts foams. Particular attention is therefore paid to performing the calculation with absorption indices (0.5-8) that preserve the opacity of each strut. From a thorough analysis of the ray transport within all the foams, where the Representative Elementary Volumes used for computing the homogenized radiative properties were known beforehand, a general and simple law is established that connects the normal spectral emittance, on the one hand, and the open porosity and the complex index of refraction, on the other hand. In the field of the thermal conversion of solar energy, for example, the new law gives relevant insight on the radiative performance of highly porous foams that are virtually coated with materials that are known for possessing an undeniable spectral selectivity when they are shaped as dense samples.

  20. Photocatalytic activity of Ag/ZnO core–shell nanoparticles with shell thickness as controlling parameter under green environment

    Rajbongshi, Himanshu; Bhattacharjee, Suparna; Datta, Pranayee


    Plasmonic Ag/ZnO core–shell nanoparticles have been synthesized via a simple two-step wet chemical method for application in Photocatalysis. The morphology, size, crystal structure, composition and optical properties of the nanoparticles are investigated by x-ray diffraction, transmission electron microscopy (TEM), FTIR spectroscopy, ultraviolet–visible (UV–Vis) absorption spectroscopy and photoluminescence (PL) spectroscopy. The shell thicknesses are varied by varying the concentration of zinc nitrate hexa-hydrate and triethanolamine. The ZnO shell coating over Ag core enhances the charge separation, whereas the larger shell thickness and increased refractive index of surrounding medium cause red shifts of surface Plasmon resonance (SPR) peak of Ag core. The photoluminescence (PL) spectra of Ag/ZnO core–shell show that the larger shell thickness quenches the near band edge UV emission of ZnO. The electrochemical impedance spectra (EIS) i.e. Nyquist plots also confirm the higher charge transfer efficiency of the Ag/ZnO core–shell nanoparticles. The Photocatalytic activities of Ag/ZnO core–shell nanoparticles are investigated by the degradation of methylene blue (MB) dye under direct sunlight irradiation. Compared to pure ZnO nanoparticles (NPs), Ag/ZnO core–shell NPs display efficient sunlight plasmonic photocatalytic activity because of the influence of SPR of Ag core and the electron sink effect. The photocatalytic activity of Ag/ZnO core–shell NPs is found to be enhanced with increase in shell thickness.

  1. Hysteresis of mode transition in a dual-struts based scramjet

    Yan, Zhang; Shaohua, Zhu; Bing, Chen; Xu, Xu


    Tests and numerical simulations were performed to investigate the combustion performance of a dual-staged scramjet combustor. High enthalpy vitiated inflow at a total temperature of 1231 K was supplied using a hydrogen-combustion heater. The inlet Mach number was 2.0. Liquid kerosene was injected into the combustor using the dual crossed struts. Three-dimensional Reynolds averaged reacting flow was solved using a two-equation k-ω SST turbulence model to calculate the effect of turbulent stress, and a partial-premixed flamelet model to model the effects of turbulence-chemistry interactions. The discrete phase model was utilized to simulate the fuel atomization and vaporization. For simplicity, the n-decane was chosen as the surrogate fuel with a reaction mechanism of 40 species and 141 steps. The predicted wall pressure profiles at three fuel injection schemes basically captured the axial varying trend of the experimental data. With the downstream equivalence ratio held constant, the upstream equivalence ratio was numerically increased from 0.1 to 0.4 until a steady combustion was obtained. Subsequently, the upstream equivalence ratio was decreased from 0.4 to 0.1 once again. Two ramjet modes with different wall pressure profiles and corresponding flow structures were captured under the identical upstream equivalence ratio of 0.1, illustrating an obvious hysteresis phenomenon. The mechanism of this hysteresis was explained by the transition hysteresis of the pre-combustion shock train in the isolator.

  2. Analysis of the deflection of a strut-type lattice girder truss

    M.N. Kirsanov


    Full Text Available The analytical dependence of the deflection of a statically determinate plane elastic truss with a uniform loading of the upper zone has been found. Forces in rods were determined using the joint isolation method. A system of equilibrium equations has been compiled in matrix form. Midspan deflection has been calculated based on the Maxwell-Mohr formula. All character conversion has been executed in the Maple computer algebra system. The method of induction on the number of panels in the truss was used. Recurrent equations for general members of the sequences of coefficients were obtained and solved using the genfunc operators package from the Maple system. The dependencies of the forces in the rods of the truss and of its deflection on the number of panels are non-monotonic, which is generally characteristic of lattice struts. We have also shown that for an odd number of panels the truss is instantaneously variable. The distribution of possible nodal velocities is given for this case.

  3. Ventilation Inception and Washout, Scaling, and Effects on Hydrodynamic Performance of a Surface Piercing Strut

    Harwood, Casey; Young, Yin Lu; Ceccio, Steven


    High-lift devices that operate at or near a fluid free surface (such as surface-piercing or shallowly-submerged propellers and hydrofoils) are prone to a multiphase flow phenomenon called ventilation, wherein non-condensable gas is entrained in the low-pressure flow, forming a cavity around the body and dramatically altering the global hydrodynamic forces. Experiments are being conducted at the University of Michigan's towing tank using a canonical surface-piercing strut to investigate atmospheric ventilation. The goals of the work are (i) to gain an understanding of the dominant physics in fully wetted, partially ventilated, and fully ventilated flow regimes, (ii) to quantify the effects of governing dimensionless parameters on the transition between flow regimes, and (iii) to develop scaling relations for the transition between flow regimes. Using theoretical arguments and flow visualization techniques, new criteria are developed for classifying flow regimes and transition mechanisms. Unsteady transition mechanisms are described and mapped as functions of the governing non-dimensional parameters. A theoretical scaling relationship is developed for ventilation washout, which is shown to adequately capture the experimentally-observed washout boundary. This material is based upon work supported by the National Science Foundation Graduate Student Research Fellowship under Grant No. DGE 1256260. Support also comes from the Naval Engineering Education Center (Award No. N65540-10-C-003).

  4. Core-shell silicon nanowire solar cells.

    Adachi, M M; Anantram, M P; Karim, K S


    Silicon nanowires can enhance broadband optical absorption and reduce radial carrier collection distances in solar cell devices. Arrays of disordered nanowires grown by vapor-liquid-solid method are attractive because they can be grown on low-cost substrates such as glass, and are large area compatible. Here, we experimentally demonstrate that an array of disordered silicon nanowires surrounded by a thin transparent conductive oxide has both low diffuse and specular reflection with total values as low as nanowire facilitates enhancement in external quantum efficiency using two different active shell materials: amorphous silicon and nanocrystalline silicon. As a result, the core-shell nanowire device exhibits a short-circuit current enhancement of 15% with an amorphous Si shell and 26% with a nanocrystalline Si shell compared to their corresponding planar devices.

  5. Spiral Shell Collection


    In 1988 Zheng Haigen, a seaman with the Towboat Company of the Shanghai Salvage Bureau, began collecting spiral shells. Today he has more than 600 in his collection. The most valuable are the rare parrot shell and a shell whose spirals wind counter-clockwise. In 1991 a miniature conch with a diameter of 0.31 millimeters that he found buried in tons of sand made the Guinness Book of World Records.

  6. Off-Shell Tachyons

    Tang, Yi-Lei


    The idea that the new particles invented in some models beyond the standard model can appear only inside the loops is attractive. In this paper, we fill these loops with off-shell tachyons, leading to a solution of the zero results of the loop diagrams involving the off-shell non-tachyonic particles. We also calculate the Passarino-Veltman $A_0^o$ and $B_0^o$ of the off-shell tachyons.

  7. Shell-like structures

    Altenbach, Holm


    In this volume, scientists and researchers from industry discuss the new trends in simulation and computing shell-like structures. The focus is put on the following problems: new theories (based on two-dimensional field equations but describing non-classical effects), new constitutive equations (for materials like sandwiches, foams, etc. and which can be combined with the two-dimensional shell equations), complex structures (folded, branching and/or self intersecting shell structures, etc.) and shell-like structures on different scales (for example: nano-tubes) or very thin structures (similar

  8. Impact of Implantation Technique and Plaque Morphology on Strut Embedment and Scaffold Expansion of Polylactide Bioresorbable Scaffold - Insights From ABSORB Japan Trial.

    Sotomi, Yohei; Onuma, Yoshinobu; Dijkstra, Jouke; Eggermont, Jeroen; Liu, Shengnan; Tenekecioglu, Erhan; Zeng, Yaping; Asano, Taku; de Winter, Robbert J; Popma, Jeffrey J; Kozuma, Ken; Tanabe, Kengo; Serruys, Patrick W; Kimura, Takeshi


    The optimal implantation technique for the bioresorbable scaffold (Absorb, Abbott Vascular) is still a matter of debate. The purpose of the present study was to evaluate the effect of implantation technique on strut embedment and scaffold expansion.Methods and Results:Strut embedment depth and scaffold expansion index assessed by optical coherence tomography (OCT) (minimum scaffold area/reference vessel area) were evaluated in the ABSORB Japan trial (OCT subgroup: 87 lesions) with respect to implantation technique using either quantitative coronary angiography (QCA) or OCT. Strut embedment was assessed at the strut level (n=667), while scaffold expansion was assessed at the lesion level (n=81). The mean embedment depth was 63±59 µm. Balloon sizing and inflation pressure had no direct effect on strut embedment. Plaque morphology affected strut embedment [nonatherosclerotic (58.9±54.3 µm), fibroatheroma (73.3±59.6 µm), fibrous plaque (59.7±51.1 µm), and fibrocalcific plaque (-3.1±61.6 µm, negative value means malapposition), P <0.001]. The balloon-artery ratio positively correlated with the expansion index. This relationship was stronger when the OCT-derived reference vessel diameter (RVD) was used as a reference for balloon selection rather than the QCA-derived one [predilatation (Pearson correlation r: QCA: 0.167 vs. OCT: 0.552), postdilatation (QCA: 0.316 vs. OCT: 0.717)]. Underlying plaque morphology influenced strut embedment, whereas implantation technique had no direct effect on it. Optimal balloon sizing based on OCT-derived RVD might be recommended. However, the safety of such a strategy should be investigated in a prospective trial. (Circ J 2016; 80: 2317-2326).

  9. Core-shell microspheres with porous nanostructured shells for liquid chromatography.

    Ahmed, Adham; Skinley, Kevin; Herodotou, Stephanie; Zhang, Haifei


    The development of new stationary phase has been the key aspect for fast and efficient high-performance liquid chromatography separation with relatively low backpressure. Core-shell particles, with a solid core and porous shell, have been extensively investigated and commercially manufactured in the last decade. The excellent performance of core-shell particles columns has been recorded for a wide range of analytes, covering small and large molecules, neutral and ionic (acidic and basic), biomolecules, and metabolites. In this review, we firstly introduce the advance and advantages of core-shell particles (or more widely known as superficially porous particles) against non-porous particles and fully porous particles. This is followed by the detailed description of various methods used to fabricate core-shell particles. We then discuss the applications of common silica core-shell particles (mostly commercially manufactured), spheres-on-sphere particles, and core-shell particles with a non-silica shell. This review concludes with a summary and perspective on the development of stationary phase materials for high-performance liquid chromatography applications. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  10. Optimised photocatalytic hydrogen production using core–shell AuPd promoters with controlled shell thickness

    Jones, Wilm; Su, Ren; Wells, Peter


    on photocatalytic performance remains unclear. Here we report the synthesis of core–shell structured AuPd NPs with the controlled deposition of one and two monolayers (ML) equivalent of Pd onto Au NPs by colloidal and photodeposition methods. We have determined the shell composition and thickness......The development of efficient photocatalytic routines for producing hydrogen is of great importance as society moves away from energy sources derived from fossil fuels. Recent studies have identified that the addition of metal nanoparticles to TiO2 greatly enhances the photocatalytic performance...... of these materials towards the reforming of alcohols for hydrogen production. The core–shell structured Au–Pd bimetallic nanoparticle supported on TiO2 has being of interest as it exhibited extremely high quantum efficiencies for hydrogen production. However, the effect of shell composition and thickness...

  11. Concave Pd-Pt Core-Shell Nanocrystals with Ultrathin Pt Shell Feature and Enhanced Catalytic Performance.

    Zhang, Ying; Bu, Lingzheng; Jiang, Kezhu; Guo, Shaojun; Huang, Xiaoqing


    One-pot creation of unique concave Pd-Pt core-shell polyhedra has been developed for the first time using an efficient approach. Due to the concave feature and ultrathin Pt shell, the created Pd-Pt core-shell polyhedra exhibit enhanced catalytic performance in both the electrooxidation of methanol and hydrogenation of nitrobenzene, as compared with commercial Pt black and Pd black catalysts. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Limit-point buckling analyses using solid, shell and elements

    Killpack, Marc; Abed-Meraim, Farid [CNRS, Metz Cedex (France)


    In this paper, the recently-developed solid-shell element SHB8PS is used for the analysis of a representative set of popular limit-point buckling benchmark problems. For this purpose, the element has been implemented in Abaqus/Standard finite element software and the modified Riks method was employed as an efficient path-following strategy. For the benchmark problems tested, the new element shows better performance compared to solid elements and often performs as well as state-of-the-art shell elements. In contrast to shell elements, it allows for the accurate prescription of boundary conditions as applied to the actual edges of the structure.

  13. Rigid-strut-containing crown ethers and [2]catenanes for incorporation into metal-organic frameworks.

    Zhao, Yan-Li; Liu, Lihua; Zhang, Wenyu; Sue, Chi-Hau; Li, Qiaowei; Miljanić, Ognjen S; Yaghi, Omar M; Stoddart, J Fraser


    To introduce crown ethers into the struts of metal-organic frameworks (MOFs), general approaches have been developed for the syntheses of dicarboxylic acid dibenzo[30]crown-10 (DB30C10DA), dicarboxylic acid di-2,3-naphtho[30]crown-10 (DN30C10DA), dicarboxylic acid bisparaphenylene[34]crown-10 (BPP34C10DA), and dicarboxylic acid 1,5-naphthoparaphenylene[36]crown-10 (NPP36C10DA). These novel crown ethers not only retain the characteristics of their parent crown ethers since they can 1) bind cationic guests and 2) serve as templates for making mechanically interlocked molecules (MIMs), such as catenanes and rotaxanes, but they also present coordination sites to connect with secondary building units (SBUs) in MOFs. The binding behavior of BPP34C10DA with 1,1'-dimethyl-4,4'-bipyridinium bis(hexafluorophosphate) (DMBP2.PF(6)) has been investigated by means of UV/Vis, fluorescence, and NMR spectroscopic techniques. The crystal superstructure of the complex DMBP2.PF(6) subset BPP34C10DA was determined by X-ray crystallography. The NPP36C10DA-based [2]catenane (H(2)NPP36C10DC-CAT4.PF(6)) and the BPP34C10DA-based [2]catenane (H(2)BPP34C10DC-CAT4.PF(6)) were prepared in DMF at room temperature by the template-directed clipping reactions of the planarly chiral NPP36C10DA and BPP34C10DA with 1,1'-[1,4-phenylenebis(methylene)]di-4,4'-bipyridin-1-ium bis(hexafluorophosphate) and 1,4-bis(bromomethyl)benzene, respectively. The crystal structure of the dimethyl ester (BPP34C10DE-CAT4.PF(6)) of the [2]catenane H(2)BPP34C10DC-CAT4.PF(6) was investigated by X-ray crystallography, which revealed racemic R and S isomers with planar chirality present in the crystal in a 1:1 ratio. These crown ether based struts serve as excellent organic ligands to bind with transition metal ions in the construction of MOFs: the crown ethers BPP34C10DA and NPP36C10DA in the presence of Zn(NO(3))(2)4.H(2)O afforded the MOF-1001 and MOF-1002 frameworks, respectively. The crystal structures of MOF-1001 and

  14. 基于Struts架构的网上书店系统的研究与设计%Research and Design of Online Bookstore System Based on Struts Framework



    With the development of Internet technology,the open source framework Struts provide new developing platform for Web ap-plication system,the application system used the platform has high execution efficiency and strong extensibility. System based on work-flow,adopting Struts technology,using the Web application layer,completed the construction of online bookstore shopping platform,reali-zing the business logic and the background management,involving the user management,news management,books management,order management,membership management,traffic statistics analysis,search and other functions. The design of the system gives full play to the advantages of the Struts framework,realizes low coupling of multi-layer development,reusing of design and code,improving the soft-ware maintainability,scalability and speed of development. System development to a certain extent,improves the sales efficiency and ef-fective management of the bookstore,easy to buy books for customers.%随着Internet技术的发展,Struts开源框架为Web应用系统提供全新的开发平台,利用该平台开发的应用系统执行效率高、扩展性强。系统以工作流为核心,采用Struts技术,利用Web应用的分层,完成了网上书店购物平台的构建,实现前台业务逻辑与后台管理,包括用户管理、新闻管理、书籍管理、订单管理、会员资料管理、流量统计分析、搜索等功能。系统的设计充分发挥了Struts框架的优势,实现多层开发的低耦合、设计和代码的重用,提高了软件可维护性、可扩展性和开发速度。系统的开发在一定程度上提高了书店的销售效率及有效管理,方便用户购买书籍。

  15. Microstructural and optical properties of CdSe/CdS/ZnS core-shell-shell quantum dots.

    Lee, Dea Uk; Kim, Dae Hun; Choi, Dong Hyuk; Kim, Sang Wook; Lee, Hong Seok; Yoo, Keon-Ho; Kim, Tae Whan


    CdSe/CdS/ZnS core-shell-shell quantum dots (QDs) were synthesized by using a solution process. High-resolution transmission electron microscopy images and energy dispersive spectroscopy profiles confirmed that stoichiometric CdSe/CdS/ZnS core-shell-shell QDs were formed. Ultraviolet-visible absorption and photoluminescence (PL) spectra of CdSe/CdS/ZnS core-shell-shell QDs showed the dominant excitonic transitions from the ground electronic subband to the ground hole subband (1S(e)-1S(3/2)(h)). The PL mechanism is suggested; the carriers generated by the exciting high-energy photons in the shell region are relaxed to the band-edge states of the core region and recombined to emit lower-energy photons. The activation energy of the carriers confined in the CdSe/CdS/ZnS core-shell-shell QDs, as obtained from temperature-dependent PL spectra, was 200 meV. The quantum efficiency of the CdSe/CdS/ZnS core-shell-shell QDs at 300 K was estimated to be approximately 57%.

  16. Stents Eluting 6-Mercaptopurine Reduce Neointima Formation and Inflammation while Enhancing Strut Coverage in Rabbits.

    Matthijs S Ruiter

    Full Text Available The introduction of drug-eluting stents (DES has dramatically reduced restenosis rates compared with bare metal stents, but in-stent thrombosis remains a safety concern, necessitating prolonged dual anti-platelet therapy. The drug 6-Mercaptopurine (6-MP has been shown to have beneficial effects in a cell-specific fashion on smooth muscle cells (SMC, endothelial cells and macrophages. We generated and analyzed a novel bioresorbable polymer coated DES, releasing 6-MP into the vessel wall, to reduce restenosis by inhibiting SMC proliferation and decreasing inflammation, without negatively affecting endothelialization of the stent surface.Stents spray-coated with a bioresorbable polymer containing 0, 30 or 300 μg 6-MP were implanted in the iliac arteries of 17 male New Zealand White rabbits. Animals were euthanized for stent harvest 1 week after implantation for evaluation of cellular stent coverage and after 4 weeks for morphometric analyses of the lesions.Four weeks after implantation, the high dose of 6-MP attenuated restenosis with 16% compared to controls. Reduced neointima formation could at least partly be explained by an almost 2-fold induction of the cell cycle inhibiting kinase p27Kip1. Additionally, inflammation score, the quantification of RAM11-positive cells in the vessel wall, was significantly reduced in the high dose group with 23% compared to the control group. Evaluation with scanning electron microscopy showed 6-MP did not inhibit strut coverage 1 week after implantation.We demonstrate that novel stents coated with a bioresorbable polymer coating eluting 6-MP inhibit restenosis and attenuate inflammation, while stimulating endothelial coverage. The 6-MP-eluting stents demonstrate that inhibition of restenosis without leaving uncovered metal is feasible, bringing stents without risk of late thrombosis one step closer to the patient.

  17. Monte Carlo Investigation on the Effect of Heterogeneities on Strut Adjusted Volume Implant (SAVI) Dosimetry

    Koontz, Craig

    Breast cancer is the most prevalent cancer for women with more than 225,000 new cases diagnosed in the United States in 2012 (ACS, 2012). With the high prevalence, comes an increased emphasis on researching new techniques to treat this disease. Accelerated partial breast irradiation (APBI) has been used as an alternative to whole breast irradiation (WBI) in order to treat occult disease after lumpectomy. Similar recurrence rates have been found using ABPI after lumpectomy as with mastectomy alone, but with the added benefit of improved cosmetic and psychological results. Intracavitary brachytherapy devices have been used to deliver the APBI prescription. However, inability to produce asymmetric dose distributions in order to avoid overdosing skin and chest wall has been an issue with these devices. Multi-lumen devices were introduced to overcome this problem. Of these, the Strut-Adjusted Volume Implant (SAVI) has demonstrated the greatest ability to produce an asymmetric dose distribution, which would have greater ability to avoid skin and chest wall dose, and thus allow more women to receive this type of treatment. However, SAVI treatments come with inherent heterogeneities including variable backscatter due to the proximity to the tissue-air and tissue-lung interfaces and variable contents within the cavity created by the SAVI. The dose calculation protocol based on TG-43 does not account for heterogeneities and thus will not produce accurate dosimetry; however Acuros, a model-based dose calculation algorithm manufactured by Varian Medical Systems, claims to accurately account for heterogeneities. Monte Carlo simulation can calculate the dosimetry with high accuracy. In this thesis, a model of the SAVI will be created for Monte Carlo, specifically using MCNP code, in order to explore the affects of heterogeneities on the dose distribution. This data will be compared to TG-43 and Acuros calculated dosimetry to explore their accuracy.

  18. Characteristics of cobalt removal by crab shell particles

    Lee, MooYeal; Kajiuchi, Toshio [Department of International Development, Tokyi Institute of Technology, Tokyo (Korea, Republic of); Kang, Hyun Ah; Yang, Ji Won [Department of Chemical Engineering, Korea Advanced Institute of Science and Technology, Taejon (Korea, Republic of)


    The characteristics of cobalt removal by raw crab shell particles was investigated. The removal efficiency of cobalt was dependent on contact time, solution pH, crab shell dose and ionic strength. Approximately 99% of the cobalt was removed within 6 hour after contact with crab shell particles. The removal efficiency was slightly affected by initial solution pH over 5.0 and the final solution pH changed to 10 spontaneously. In addition, optimum pH range of cobalt removal was broaden by the effect of crab shell addition. Maximum uptake of cobalt was 510 mg Co/g crab shell at initial pH 5.0. The removal efficiency was affected slightly by ionic strength up to 2.0 M of NaCl. From the results of scanning electron microscopy (SEM) and energy dispersive spectrometer (EDS), the removal of cobalt by crab shell was mainly through the dissolution of CaCO{sub 3} followed by precipitation of Co(OH){sub 2} and CoCO{sub 3} and then the precipitates were adsorbed to the chitin on the surface of crab shell particles. Compared to the results with activated carbon column, the addition of crab shell to activated carbon column increased the removal efficiency dramatically.(author)

  19. Infection rate in mandibular angle fractures treated with a 2.0-mm 8-hole curved strut plate.

    Bui, Peter; Demian, Nagi; Beetar, Patrick


    The aim of this study was to determine the rate of postoperative infection and the efficacy of removing teeth in the line of mandibular angle fractures treated with 2.0-mm 8-hole titanium curved strut plates. Our understanding is that this method of repair is currently being used only in a few centers in the United States. A retrospective review of mandibular angle fractures treated with a 2.0-mm 8-hole strut plate during a 4-year period. Postoperative antibiotics were given for 1 week. Follow-up appointments were 4 weeks or longer. A nonchewing diet was instructed for 6 weeks. Data for all selected patients include the information such as age, gender, etiology of injuries, medical history, concurrent injuries, nerve deficits, pre- and postoperative antibiotic administration, postop infection, a presence or absence of teeth in the line of fractures, and whether these teeth were removed. Four patients (4 of 49 or 8.2%) developed infections. Two of those patients had a tooth in the line of a fracture that was retained (2 of 14 or 14%). The third had a tooth in the line of a fracture that was extracted (1 of 18 or 5.6%). The fourth patient was 1 of the 17 patients who did not have teeth in the line of fracture and developed infection (1 of 17 or 5.9%). None of the patients developed failed hardware, malunion, nonunion, malocclusion, or iatrogenic nerve injury. The use of a 2.0-mm 8-hole strut plate is associated with a low infection rate (8.2%). The infection rate for those mandibular angle fractures with teeth in the line of fracture retained was 14% compared with 5.6% for those fractures with the teeth in the line of fracture extracted.

  20. Error modeling, sensitivity analysis and assembly process of a class of 3-DOF parallel kinematic machines with parallelogram struts


    This paper presents an error modeling methodology that enables the tolerance design, assembly and kinematic calibration of a class of 3-DOF parallel kinematic machines with parallelogram struts to be integrated into a unified framework. The error mapping function is formulated to identify the source errors affecting the uncompensable pose error. The sensitivity analysis in the sense of statistics is also carried out to investigate the influences of source errors on the pose accuracy. An assembly process that can effectively minimize the uncompensable pose error is proposed as one of the results of this investigation.

  1. Penetration of Günther Tulip filter struts through an introducer sheath: case report and safety concerns.

    Contractor, Sohail G; Merkulov, Alex; Bhatti, Waseem; Lee, Michael; Gardner, Kim


    The authors present a patient who had a Günther-Tulip inferior vena cava filter placed under fluoroscopic guidance. The filter struts were seen to penetrate through the introducer sheath at deployment. This was believed to be secondary to a kink in the sheath at the site of venous entry and was due to the patient's nuchal obesity as well as his inability to turn his head to the opposite side. The introducer sheath was then placed through a long reinforced metal sheath through which the filter was then placed without complication.

  2. Struts技术在网站开发中的应用%Application of Struts Technology in Website Development



    Struts technology is JSP technology to develop website using the framework of technology, is a MVC implementation. Unified program structure style, automatic requested data to be filled into the object, and to simplify the interface code.%Struts技术是JSP技术开发网站时使用的框架技术.是MVC模式的实现.统一程序结构风格,自动将请求的数据填充到对象,并简化界面代码.

  3. Design & Performances of Coconut De-Shelling Machine

    Mr. Ketan K.Tonpe


    Full Text Available The traditional method used in India, for the separation of copra and shell from partially-dried split coconuts, is labour intensive. To overcome this problem, a power operated coconut de-shelling machine was designed and developed. A coconut de-shelling machine comprising of cutter with belt drive. Performances test analysis conducted show that the machine de-shelled the fruits without nut breakage and also that its average de-shelling efficiency and capacity are 90% and 195 coconut per hour. All materials used in the fabrication of this machine are of standard specification and locally sourced. The estimated cost of producing one unit of the machine is twenty five thousand six hundred (Rs.25, 600. The machine also eliminated dependency on the epileptic public electric power supply in our rural areas which constitutes the major obstacle in the use of other mechanized coconut de-shelling equipment in the rural area.

  4. UHPFRC in large span shell structures

    Ter Maten, R.N.; Grunewald, S.; Walraven, J.C.


    Ultra-High Performance Fibre-Reinforced Concrete (UHPFRC) is an innovative concrete type with a high compressive strength and a far more durable character compared to conventional concrete. UHPFRC can be applied in structures with aesthetic appearance and high material efficiency. Shell structures a

  5. 基于Struts+Hibernate+Spring的整合架构及其在Web开发中的应用%Application in Web Development Use Based on Struts+Hibernate+Spring Integrated Framework

    田秀彦; 李忠; 罗士美; 邓力强


    Struts、Hibernate和Spring是当今企业开发中用到的比较新的技术.Struts 是Apache软件组织提供的一项开放源码项目,它为Java Web应用提供了模型-视图-控制器(Model-View- Controller,简称MVC)框架,尤其适用于开发大型可扩展的Web应用.Hibernate是目前在JAVA界使用非常广泛的ORMapping的一种实现 ,可以实现关系型数据库和对象之间的映射.Spring是为了解决企业应用开发的复杂性而创建的轻量级的框架.本文介绍了三种技术的框架结构和特点,并且通过一个具体的例子说明了Struts+Hibernate+Spring整合架构在Web开发中的使用.

  6. Cu₂-xSe@mSiO₂-PEG core-shell nanoparticles: a low-toxic and efficient difunctional nanoplatform for chemo-photothermal therapy under near infrared light radiation with a safe power density.

    Liu, Xijian; Wang, Qian; Li, Chun; Zou, Rujia; Li, Bo; Song, Guosheng; Xu, Kaibing; Zheng, Yun; Hu, Junqing


    A low-toxic difunctional nanoplatform integrating both photothermal therapy and chemotherapy for killing cancer cells using Cu₂-xSe@mSiO₂-PEG core-shell nanoparticles is reported. Silica coating and further PEG modification improve the hydrophilicity and biocompatibility of copper selenide nanoparticles. As-prepared Cu₂-xSe@mSiO₂-PEG nanoparticles not only display strong near infrared (NIR) region absorption and good photothermal effect, but also exhibit excellent biocompatibility. The mesoporous silica shell is provided as the carrier for loading the anticancer drug, doxorubicin (DOX). Moreover, the release of DOX from Cu₂-xSe@mSiO₂-PEG core-shell nanoparticles can be triggered by pH and NIR light, resulting in a synergistic effect for killing cancer cells. Importantly, the combination of photothermal therapy and chemotherapy driven by NIR radiation with safe power density significantly improves the therapeutic efficacy, and demonstrates better therapeutic effects for cancer treatment than individual therapy.

  7. Test Program for High Efficiency Gas Turbine Exhaust Diffuser

    Norris, Thomas R.


    This research relates to improving the efficiency of flow in a turbine exhaust, and thus, that of the turbine and power plant. The Phase I SBIR project demonstrated the technical viability of “strutlets” to control stalls on a model diffuser strut. Strutlets are a novel flow-improving vane concept intended to improve the efficiency of flow in turbine exhausts. Strutlets can help reduce turbine back pressure, and incrementally improve turbine efficiency, increase power, and reduce greenhouse gas emmission. The long-term goal is a 0.5 percent improvement of each item, averaged over the US gas turbine fleet. The strutlets were tested in a physical scale model of a gas turbine exhaust diffuser. The test flow passage is a straight, annular diffuser with three sets of struts. At the end of Phase 1, the ability of strutlets to keep flow attached to struts was demonstrated, but the strutlet drag was too high for a net efficiency advantage. An independently sponsored followup project did develop a highly-modified low-drag strutlet. In combination with other flow improving vanes, complicance to the stated goals was demonstrated for for simple cycle power plants, and to most of the goals for combined cycle power plants using this particular exhaust geometry. Importantly, low frequency diffuser noise was reduced by 5 dB or more, compared to the baseline. Appolicability to other diffuser geometries is yet to be demonstrated.

  8. 基于Struts和Hibernate的Web应用开发%Web Application Development Based on Struts and Hibernate

    王海涛; 贾宗璞


    Model realization of Struts have some problems, such as complex JDBC connecting to database, high coupling between layers and difficult code maintenance, et al. Aiming at these problems, this paper presents a Web application development scheme based on Struts and Hibernate. It really achieves the loose coupling between layers and easy maintenance, reduces the difficulty of development of business model.Through part of development codes and running window of student management system, it explains the process of integration and proves the feasibility of integrated solutions.%Struts框架在模型部分的实现存在JDBC连接数据库复杂、层间高耦合和难维护等问题.为此,提出一种整合Struts和Hibernate的Web应用开发方案,可实现层间的松散耦合和易维护,降低业务模型开发难度.通过学生管理系统开发实例的部分代码和运行界面说明该方案的整合应用过程,并验证其可行性.

  9. Wireless energy transfer between anisotropic metamaterials shells

    Diaz-Rubio, Ana; Sanchez-Dehesa, Jose


    The behavior of strongly coupled Radial Photonic Crystals shells is investigated as a potential alternative to transfer electromagnetic energy wirelessly. These sub-wavelength resonant microstructures, which are based on anisotropic metamaterials, can produce efficient coupling phenomena due to their high quality factor. A configuration of selected constitutive parameters (permittivity and permeability) is analyzed in terms of its resonant characteristics. The coupling to loss ratio between two coupled resonators is calculated as a function of distance, the maximum (in excess of 300) is obtained when the shells are separated by three times their radius. Under practical conditions an 83% of maximum power transfer has been also estimated.

  10. Elastic platonic shells.

    Yong, Ee Hou; Nelson, David R; Mahadevan, L


    On microscopic scales, the crystallinity of flexible tethered or cross-linked membranes determines their mechanical response. We show that by controlling the type, number, and distribution of defects on a spherical elastic shell, it is possible to direct the morphology of these structures. Our numerical simulations show that by deflating a crystalline shell with defects, we can create elastic shell analogs of the classical platonic solids. These morphologies arise via a sharp buckling transition from the sphere which is strongly hysteretic in loading or unloading. We construct a minimal Landau theory for the transition using quadratic and cubic invariants of the spherical harmonic modes. Our approach suggests methods to engineer shape into soft spherical shells using a frozen defect topology.

  11. Dynamic Analysis of Shells

    Charles R. Steele


    Full Text Available Shell structures are indispensable in virtually every industry. However, in the design, analysis, fabrication, and maintenance of such structures, there are many pitfalls leading to various forms of disaster. The experience gained by engineers over some 200 years of disasters and brushes with disaster is expressed in the extensive archival literature, national codes, and procedural documentation found in larger companies. However, the advantage of the richness in the behavior of shells is that the way is always open for innovation. In this survey, we present a broad overview of the dynamic response of shell structures. The intention is to provide an understanding of the basic themes behind the detailed codes and stimulate, not restrict, positive innovation. Such understanding is also crucial for the correct computation of shell structures by any computer code. The physics dictates that the thin shell structure offers a challenge for analysis and computation. Shell response can be generally categorized by states of extension, inextensional bending, edge bending, and edge transverse shear. Simple estimates for the magnitudes of stress, deformation, and resonance in the extensional and inextensional states are provided by ring response. Several shell examples demonstrate the different states and combinations. For excitation frequency above the extensional resonance, such as in impact and acoustic excitation, a fine mesh is needed over the entire shell surface. For this range, modal and implicit methods are of limited value. The example of a sphere impacting a rigid surface shows that plastic unloading occurs continuously. Thus, there are no short cuts; the complete material behavior must be included.

  12. Shape-changing shell-like structures.

    Pagitz, M; Bold, J


    Plants such as Dionaea muscipula (Venus Flytrap) can change the shape of their shell-like leaves by actively altering the cell pressures. These leaves are hydraulic actuators that do not require any complex controls and that possess an energy efficiency that is unmatched by natural or artificial muscles (Huber et al 1997 Proc. R. Soc. A 453 2185-205). We extend our previous work (Pagitz et al 2012 Bioinspir. Biomim. 7 016007) on pressure-actuated cellular structures by introducing a concept for shape-changing shell-like structures that can significantly alter their Gaussian curvature. The potential of this concept is demonstrated by a hemispherical shell that can reversibly change the sign of its Gaussian curvature. Furthermore, it is shown that a snap-through behaviour, similar to the one known from Dionaea muscipula, can be achieved by lowering the pressure in a single layer of cells.

  13. Multi-Shell Hollow Nanogels with Responsive Shell Permeability.

    Schmid, Andreas J; Dubbert, Janine; Rudov, Andrey A; Pedersen, Jan Skov; Lindner, Peter; Karg, Matthias; Potemkin, Igor I; Richtering, Walter


    We report on hollow shell-shell nanogels with two polymer shells that have different volume phase transition temperatures. By means of small angle neutron scattering (SANS) employing contrast variation and molecular dynamics (MD) simulations we show that hollow shell-shell nanocontainers are ideal systems for controlled drug delivery: The temperature responsive swelling of the inner shell controls the uptake and release, while the thermoresponsive swelling of the outer shell controls the size of the void and the colloidal stability. At temperatures between 32 °C shell. Computer simulations showed, that temperature induced switching of the permeability of the inner shell allows for the encapsulation in and release of molecules from the cavity.

  14. Hollow Pollen Shells to Enhance Drug Delivery

    Alberto Diego-Taboada


    Full Text Available Pollen grain and spore shells are natural microcapsules designed to protect the genetic material of the plant from external damage. The shell is made up of two layers, the inner layer (intine, made largely of cellulose, and the outer layer (exine, composed mainly of sporopollenin. The relative proportion of each varies according to the plant species. The structure of sporopollenin has not been fully characterised but different studies suggest the presence of conjugated phenols, which provide antioxidant properties to the microcapsule and UV (ultraviolet protection to the material inside it. These microcapsule shells have many advantageous properties, such as homogeneity in size, resilience to both alkalis and acids, and the ability to withstand temperatures up to 250 °C. These hollow microcapsules have the ability to encapsulate and release actives in a controlled manner. Their mucoadhesion to intestinal tissues may contribute to the extended contact of the sporopollenin with the intestinal mucosa leading to an increased efficiency of delivery of nutraceuticals and drugs. The hollow microcapsules can be filled with a solution of the active or active in a liquid form by simply mixing both together, and in some cases operating a vacuum. The active payload can be released in the human body depending on pressure on the microcapsule, solubility and/or pH factors. Active release can be controlled by adding a coating on the shell, or co-encapsulation with the active inside the shell.

  15. Cu2-xSe@mSiO2-PEG core-shell nanoparticles: a low-toxic and efficient difunctional nanoplatform for chemo-photothermal therapy under near infrared light radiation with a safe power density

    Liu, Xijian; Wang, Qian; Li, Chun; Zou, Rujia; Li, Bo; Song, Guosheng; Xu, Kaibing; Zheng, Yun; Hu, Junqing


    A low-toxic difunctional nanoplatform integrating both photothermal therapy and chemotherapy for killing cancer cells using Cu2-xSe@mSiO2-PEG core-shell nanoparticles is reported. Silica coating and further PEG modification improve the hydrophilicity and biocompatibility of copper selenide nanoparticles. As-prepared Cu2-xSe@mSiO2-PEG nanoparticles not only display strong near infrared (NIR) region absorption and good photothermal effect, but also exhibit excellent biocompatibility. The mesoporous silica shell is provided as the carrier for loading the anticancer drug, doxorubicin (DOX). Moreover, the release of DOX from Cu2-xSe@mSiO2-PEG core-shell nanoparticles can be triggered by pH and NIR light, resulting in a synergistic effect for killing cancer cells. Importantly, the combination of photothermal therapy and chemotherapy driven by NIR radiation with safe power density significantly improves the therapeutic efficacy, and demonstrates better therapeutic effects for cancer treatment than individual therapy.A low-toxic difunctional nanoplatform integrating both photothermal therapy and chemotherapy for killing cancer cells using Cu2-xSe@mSiO2-PEG core-shell nanoparticles is reported. Silica coating and further PEG modification improve the hydrophilicity and biocompatibility of copper selenide nanoparticles. As-prepared Cu2-xSe@mSiO2-PEG nanoparticles not only display strong near infrared (NIR) region absorption and good photothermal effect, but also exhibit excellent biocompatibility. The mesoporous silica shell is provided as the carrier for loading the anticancer drug, doxorubicin (DOX). Moreover, the release of DOX from Cu2-xSe@mSiO2-PEG core-shell nanoparticles can be triggered by pH and NIR light, resulting in a synergistic effect for killing cancer cells. Importantly, the combination of photothermal therapy and chemotherapy driven by NIR radiation with safe power density significantly improves the therapeutic efficacy, and demonstrates better therapeutic

  16. An 8-Node Shell Element for Nonlinear Analysis of Shells Using the Refined Combination of Membrane and Shear Interpolation Functions

    Woo-Young Jung


    Full Text Available An improved 8-node shell finite element applicable for the geometrically linear and nonlinear analyses of plates and shells is presented. Based on previous first-order shear deformation theory, the finite element model is further improved by the combined use of assumed natural strains and different sets of collocation points for the interpolation of the different strain components. The influence of the shell element with various conditions such as locations, number of enhanced membranes, and shear interpolation is also identified. By using assumed natural strain method with proper interpolation functions, the present shell element generates neither membrane nor shear locking behavior even when full integration is used in the formulation. Furthermore, to characterize the efficiency of these modifications of the 8-node shell finite elements, numerical studies are carried out for the geometrically linear and non-linear analysis of plates and shells. In comparison to some other shell elements, numerical examples for the methodology indicate that the modified element described locking-free behavior and better performance. More specifically, the numerical examples of annular plate presented herein show good validity, efficiency, and accuracy to the developed nonlinear shell element.

  17. Design and Realization of Information Communication Platform System Based on Struts+Spring+Hibernate Framework%基于Struts+Spring+Hibernate框架的信息交流平台的设计与实现



    以开发信息交流平台系统为背景,对基于MVC模式的Struts框架、Hibernate的ORM机制和对持久对象持久化的管理以及Spring IOC(控制反转)技术进行了探讨,整合这三种框架:表现层使用Struts;业务层使用Spring;持久层使用Hibernate进行系统的开发.此外,结合具体的实例对系统的实现作了详细的说明,验证了实现方法的可行性.

  18. Research and Development of the Injection Mould Quotation System Based on Spring+Struts+Hibernate%基于Spring+Struts+Hibernate注塑模具报价系统的研发

    黄志明; 王天擎



  19. Research and implementation of MVC pattern in J2EE project with struts%在J2EE项目中使用Struts 对 MVC模式的研究与实现

    黄丹霞; 杨璐; 崔永普



  20. Clinical Characteristics and Prognosis of Peri-strut Low-intensity Area Detected by Optical Coherence Tomography

    De-Wei Wu; Meng-Yue Yu; Hai-Yang Gao; Zhe He; Jing Yao; Cheng Ding; Bo Xu


    Background: Peri-strut low-intensity area (PLIA) is a typical image pattern ofneointima detected by optical coherence tomography (OCT) after stent implantation.However, few studies evaluated the predictors and prognosis of the PLIA;therefore, we aimed to explore the genesis and prognosis of PLIA detected by OCT in this study.Methods: Patients presenting neointimal hyperplasia documented by OCT reexamination after percutaneous coronary intervention were prospectively included from 2009 to 2011.Peri-strut intensity was analyzed and classified into two patterns: Low-intensity and high-intensity.Clinical characteristics were analyzed to assess their contribution to peri-strut intensity patterns.Follow-up were performed in patients who did not receive revascularization during OCT reexamination, and the prognosis of the patients was evaluated.Results: There were 128 patients underwent OCT reexamination after stent implantation included in the study.PLIA was detected in 22 (17.2%) patients.The incidence of PLIA was positively correlated with serum triglyceride (odds ratio [OR]: 2.11, 95% confidence interval [CI]: 1.14-3.90, P =0.017), low-density lipoprotein (OR: 2.61, 95% CI: 1.22-5.66, P =0.015), history of cerebrovascular disease (OR: 101.11, 95% CI: 6.54-1562.13, P < 0.001), and initial clinical presentation of acute coronary syndrome (ACS, OR: 18.77, 95% CI: 2.73-128.83, P =0.003) while negatively correlated with stent implantation time (OR: 0.57, 95% CI: 0.33-0.98, P =0.043).The median follow-up was longer than 3.8 years.Major adverse cardiovascular events (MACEs) occurred in 7 (7.3%) patients while showed no correlation with PLIA.A total of 17 (17.7%) patients experienced unstable angina (UA) and showed significant correlation with PLIA (hazard ratio: 6.16, 95% CI: 1.25-30.33, P =0.025).Conclusions: PLIA detected by OCT was positively correlated with higher serum lipid level, history of cerebrovascular disease and initial presentation of ACS

  1. Analysis and Research on Using Struts Framework to Develop Web Application%Struts框架在Web开发中的应用

    吕凯; 李绍杰; 王莹莹


    Struts is a framework that is used to develop a Web application, it uses MVC (Model-View-Controller) design to achieve a separation between good user interface and business logic. Pointing this problem, this text analyzes the Struts framework with regard to the technical points and describes the profiles, form validation, and other characteristics, solves the Struts problems when developing Web, finally adopting an example to describe the frame of Struts.%Struts是一个用于开发Web应用程序的框架,它采用MVC(Model-View-Controller)的设计思想,很好的实现了业务逻辑和用户界面的分离.针对这一思想,该文对Struts框架所涉及的技术要点进行了分析,并对配置文件、表单验证等特性进行了详细的描述,解决了在Web开发中所涉及的Struts难点问题,最后通过一个实例对Struts框架的结构进行说明.

  2. Comparison of Single Ti6Al4V Struts Made Using Selective Laser Melting and Electron Beam Melting Subject to Part Orientation

    Volker Weißmann


    Full Text Available The use of additive manufacturing technologies to produce lightweight or functional structures is widespread. Especially Ti6Al4V plays an important role in this development field and parts are manufactured and analyzed with the aim to characterize the mechanical properties of open-porous structures and to generate scaffolds with properties specific to their intended application. An SLM and an EBM process were used respectively to fabricate the Ti6Al4V single struts. For mechanical characterization, uniaxial compression tests and hardness measurements were conducted. Furthermore, the struts were manufactured in different orientations for the determination of the mechanical properties. Roughness measurements and a microscopic characterization of the struts were also carried out. Some parts were characterized following heat treatment (hot isostatic pressing. A functional correlation was found between the compressive strength and the slenderness ratio (λ as well as the equivalent diameter (d and the height (L of EBM and SLM parts. Hardness investigations revealed considerable differences related to the microstructure. An influence of heat treatment as well as of orientation could be determined. In this work, we demonstrate the influence of the fabrication quality of single struts, the roughness and the microstructure on mechanical properties as a function of orientation.

  3. An investigation of the formation and propagation of horseshoe vortices in a strut-boundary layer interaction, and their effect on inlet distortion

    Conway, Matthew J.

    The formation and propagation of a horseshoe vortex system forming as a result of strut-boundary layer interaction is studied to determine its effect on stagnation pressure distortion in an axisymmetric supersonic inlet geometry. The effects of strut leading edge radius, pressure gradients, and curvature of the inlet walls on the vortex system are studied parametrically by performing a CFD simulation of strut-boundary layer interaction in a simplified duct geometry with flow conditions representative of the subsonic diffuser of a supersonic inlet. Leading edge fairings are studied to determine what parameters are most important for the control of the horseshoe vortex system and the reduction of stagnation pressure distortion at the fan. A fairing is designed for struts an axisymmetric, supersonic, mixed-compression inlet which reduces circumferential distortion intensity by 48% at cruise condition with 3 degrees angle of attack. Solutions are obtained to the steady state Reynolds averaged Navier-Stokes equations using WIND, a finite-difference solver developed by NASA Glenn and the USAF Arnold Engineering Development Center. The Spalart-Allmaras one equation turbulence model is used to model eddy viscosity.

  4. From shell logs to shell scripts

    Jacobs, Nico; Blockeel, Hendrik


    Analysing the use of a Unix command shell is one of the classic applications in the domain of adaptive user interfaces and user modelling. Instead of trying to predict the next command from a history of commands, we automatically produce scripts that automate frequent tasks. For this we use an ILP association rule learner. We show how to speedup the learning task by dividing it into smaller tasks, and the need for a preprocessing phase to detect frequent subsequences in the data. We illustrat...

  5. BOWOOSS: bionic optimized wood shells with sustainability

    Pohl, Göran


    In architecture, shell construction is used for the most efficient, large spatial structures. Until now the use of wood rather played a marginal role, implementing those examples of architecture, although this material offers manifold advantages, especially against the background of accelerating shortage of resources and increasing requirements concerning the energy balance. Regarding the implementation of shells, nature offers a wide range of suggestions. The focus of the examinations is on the shells of marine plankton, especially of diatoms, whose richness in species promises the discovery of entirely new construction principles. The project is targeting at transferring advantageous features of these organisms on industrial produced, modular wood shell structures. Currently a transfer of these structures in CAD - models is taking place, helping to perform stress analysis by computational methods. Micro as well as macro structures are the subject of diverse consideration, allowing to draw the necessary conclusions for an architectural design. The insights of these tests are the basis for the development of physical models on different scales, which are used to verify the different approaches. Another important aim which is promoted in the project is to enhance the competitiveness of timber construction. Downsizing of the prefabricated structural elements leads to considerable lower transportation costs as abnormal loads can be avoided as far as possible and means of transportation can be loaded with higher efficiency so that an important contribution to the sustainability in the field of architecture can also be made.

  6. NiCo2O4@La0.8Sr0.2MnO3 core-shell structured nanorods as efficient electrocatalyst for Lisbnd O2 battery with enhanced performances

    Luo, Yong; Lu, Fanliang; Jin, Chao; Wang, Yarong; Yang, Ruizhi; Yang, Chenghao


    La1-xSrxMnO3 perovskite oxides are promising electrocatalysts for Lisbnd O2 batteries because of their excellent intrinsic catalytic activity for oxygen reduction reaction (ORR). However, the relatively inert catalytic activity for oxygen evolution reaction (OER) suppresses their practical applications in Lisbnd O2 battery. Here, nanoscale NiCo2O4 (NCO) layer with high OER catalytic activity has been homogenously incorporated into the surface of La0.8Sr0.2MnO3 (LSM) nanorods to form a core-shell structure. In this typical structure, the ORR mainly occurred on the LSM core, while the OER mainly occurred on the nanoscale NCO shell, and structure damage of catalysts coming from gas evolution can be greatly avoided. The synergy of high catalytic activity and core-shell structure results in the Lisbnd O2 battery with good rate capability and excellent cycle stability, which sustains 80 cycles without capacity attenuation at a high current density of 200 mA g-1.

  7. Multifunctional Fe₃O₄@nSiO₂@mSiO₂-Fe core-shell microspheres for highly efficient removal of 1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane (DDT) from aqueous media.

    Tian, Hua; Liu, Feng; He, Junhui


    A novel multifunctional microsphere with an iron oxide-improved mesoporous silica shell and a Fe3O4@SiO2 core has been successfully prepared by a hydrothermal method and impregnation process. The resulting Fe3O4@nSiO2@mSiO2-Fe core-shell microspheres are utilized as a catalyst for the removal of 1,1,1-trichloro-2,2-bis(4-chlorophenyl) ethane (DDT) and its derivatives, i.e., 1,1-dichloro-2,2-bis(4-chlorophenyl) ethane (DDD) and 1,1-dichloro-2,2-bis(4-chlorophenyl) ethylene (DDE). The results indicated that the iron oxide nanoparticles were well dispersed on the mesoporous silica shell of Fe3O4@nSiO2@mSiO2. DDT, DDD and DDE could be quickly and effectively removed from aqueous media in 60 min, and completely dechlorinated at 350°C by Fe3O4@nSiO2@mSiO2-Fe. More importantly, the Fe3O4@nSiO2@mSiO2-Fe microspheres were superparamagnetic and could be separated and collected easily and rapidly using a magnet. Copyright © 2014 Elsevier Inc. All rights reserved.

  8. Research and application of business logic reuse based on Struts%基于Struts框架的业务逻辑复用的研究与应用

    安慧斌; 耿祥义


    Struts is a kind of mature Web development framework based on MVC pattern. It reasoiiably separates the view. the business logic and the control logic ,which and make the development process become easy and clear. But when programmers use Struts to program , it has to program the whole system from A to Z every time for a particular field business logic. Especially to the module which has the same function or independent structure,it don't reuse very well. This paper analyzes process of Struts, using software reuse technology put forward a compositive scheme of specific areas business module and Struts framework. and realize the double reuse of the architecture and the business logic on Struts.%Struts是基于MVC模式的一种成熟的Web开发框架,它合理地将表示逻辑、业务逻辑和控制逻辑分离,使得开发过程变得简洁清晰.但是程序员运用Struts开发程序时,对于某一个具体领域业务逻辑代码每次都要从头编写,特别是功能相同、结构独立的模块得不到很好的复用.本文通过分析Struts的处理流程并运用软件复用技术提出了特定领域的业务模块与Struts框架的集成方案,实现Struts框架在架构和业务的双重复用.

  9. Lead behavior in abalone shell

    Hirao, Yoshimitsu; Matsumoto, Akikazu; Yamakawa, Hiroshi; Maeda, Masaru; Kimura, Kan


    In order to gain information about the behavior of heavy metals in biological assimilation processes in a marine food chain and to investigate the possibility that lead pollution in a marine environment can be estimated by measurement of a small number of key materials from such a food chain, muscle and shell were analyzed from abalone ( Haliotis) from a shallow water locality in a Japanese coastal region. Lead concentrations in muscle were about 26 ppb for abalone of approximately 3 years old and decreased systematically with increasing age of animals sampled, to about 3.3 ppb for a specimen approximately 8 years old. Lead concentrations in shell material gradually decreased also, from 150 ppb to 82 ppb in the oldest specimen. The decrease of concentration in tissues with increasing age indicates that a mechanism for exclusion of lead during tissue growth becomes more efficient with age. Along the food chain in which abalone is the final stage, lead was enriched at the first stage, from seawater to algae, by a factor of 100. Lead was diminished at all subsequent stages of the chain. Tissue of artificially cultured abalone had four times higher lead values compared to abalone grown in natural conditions, and this appears to reflect the fact that lead concentration was three times higher in seawater in the cultured environment.

  10. Sensational spherical shells

    Lee, M. C.; Kendall, J. M., Jr.; Bahrami, P. A.; Wang, T. G.


    Fluid-dynamic and capillary forces can be used to form nearly perfect, very small spherical shells when a liquid that can solidify is passed through an annular die to form an annular jet. Gravity and certain properties of even the most ideal materials, however, can cause slight asymmetries. The primary objective of the present work is the control of this shell formation process in earth laboratories rather than space microgravity, through the development of facilities and methods that minimize the deleterious effects of gravity, aerodynamic drag, and uncontrolled cooling. The spherical shells thus produced can be used in insulation, recyclable filter materials, fire retardants, explosives, heat transport slurries, shock-absorbing armor, and solid rocket motors.

  11. Fabrication of diamond shells

    Hamza, Alex V.; Biener, Juergen; Wild, Christoph; Woerner, Eckhard


    A novel method for fabricating diamond shells is introduced. The fabrication of such shells is a multi-step process, which involves diamond chemical vapor deposition on predetermined mandrels followed by polishing, microfabrication of holes, and removal of the mandrel by an etch process. The resultant shells of the present invention can be configured with a surface roughness at the nanometer level (e.g., on the order of down to about 10 nm RMS) on a mm length scale, and exhibit excellent hardness/strength, and good transparency in the both the infra-red and visible. Specifically, a novel process is disclosed herein, which allows coating of spherical substrates with optical-quality diamond films or nanocrystalline diamond films.

  12. MVC-based Research of Struts Architecture%基于MVC的Struts框架的研究与探讨




  13. 某减震器压杆稳定性探究%A shock absorber strut bar stability inquiry

    康水库; 刘勇


    目前某矿用车减震器杆件容易出现弯曲变形,且变形方向带有不确定性和弯曲变形的位置基本相同等特征的质量问题,经分析与压杆稳定失稳状态表现形式吻合,所以对减震器进行压杆稳定性探究,并给出减震器选型的几点校核意见。%Currently a mine car shock absorber rods prone to bending deformation, and the deformation direction with uncertainty and bending position substantially the same characteristics of quality problems, the analysis Buckling instability and state forms consistent, so shock absorber strut stability were explored, and give a few comments check damper selection.

  14. Retention Models on Core-Shell Columns.

    Jandera, Pavel; Hájek, Tomáš; Růžičková, Marie


    A thin, active shell layer on core-shell columns provides high efficiency in HPLC at moderately high pressures. We revisited three models of mobile phase effects on retention for core-shell columns in mixed aqueous-organic mobile phases: linear solvent strength and Snyder-Soczewiński two-parameter models and a three-parameter model. For some compounds, two-parameter models show minor deviations from linearity due to neglect of possible minor retention in pure weak solvent, which is compensated for in the three-parameter model, which does not explicitly assume either the adsorption or the partition retention mechanism in normal- or reversed-phase systems. The model retention equation can be formulated as a function of solute retention factors of nonionic compounds in pure organic solvent and in pure water (or aqueous buffer) and of the volume fraction of an either aqueous or organic solvent component in a two-component mobile phase. With core-shell columns, the impervious solid core does not participate in the retention process. Hence, the thermodynamic retention factors, defined as the ratio of the mass of the analyte mass contained in the stationary phase to its mass in the mobile phase in the column, should not include the particle core volume. The values of the thermodynamic factors are lower than the retention factors determined using a convention including the inert core in the stationary phase. However, both conventions produce correct results if consistently used to predict the effects of changing mobile phase composition on retention. We compared three types of core-shell columns with C18-, phenyl-hexyl-, and biphenyl-bonded phases. The core-shell columns with phenyl-hexyl- and biphenyl-bonded ligands provided lower errors in two-parameter model predictions for alkylbenzenes, phenolic acids, and flavonoid compounds in comparison with C18-bonded ligands.

  15. Simulation for double shell pinch

    Wang Gang-Hua; Hu Xi-Jing; Sun Cheng-Wei


    Basic shock phenomena are presented in a composite pinch, a hybrid of the Z-pinch. The successive transfer of current within the plasma structure is demonstrated by our calculations. Properties of the shock wave are described.The current distribution between the two shells after the outer shell hitting the inner shell is also discussed.

  16. Temporal structures in shell models

    Okkels, F.


    The intermittent dynamics of the turbulent Gledzer, Ohkitani, and Yamada shell-model is completely characterized by a single type of burstlike structure, which moves through the shells like a front. This temporal structure is described by the dynamics of the instantaneous configuration of the shell...

  17. Recent Advances in Shell Evolution with Shell-Model Calculations

    Utsuno, Yutaka; Tsunoda, Yusuke; Shimizu, Noritaka; Honma, Michio; Togashi, Tomoaki; Mizusaki, Takahiro


    Shell evolution in exotic nuclei is investigated with large-scale shell-model calculations. After presenting that the central and tensor forces produce distinctive ways of shell evolution, we show several recent results: (i) evolution of single-particle-like levels in antimony and cupper isotopes, (ii) shape coexistence in nickel isotopes understood in terms of configuration-dependent shell structure, and (iii) prediction of the evolution of the recently established $N=34$ magic number towards smaller proton numbers. In any case, large-scale shell-model calculations play indispensable roles in describing the interplay between single-particle character and correlation.

  18. Novel Extrapolation Method in the Monte Carlo Shell Model

    Shimizu, Noritaka; Mizusaki, Takahiro; Otsuka, Takaharu; Abe, Takashi; Honma, Michio


    We propose an extrapolation method utilizing energy variance in the Monte Carlo shell model in order to estimate the energy eigenvalue and observables accurately. We derive a formula for the energy variance with deformed Slater determinants, which enables us to calculate the energy variance efficiently. The feasibility of the method is demonstrated for the full $pf$-shell calculation of $^{56}$Ni, and the applicability of the method to a system beyond current limit of exact diagonalization is shown for the $pf$+$g_{9/2}$-shell calculation of $^{64}$Ge.

  19. Synthesis and microwave absorption properties of yolk-shell microspheres with magnetic iron oxide cores and hierarchical copper silicate shells.

    Liu, Jiwei; Cheng, Jin; Che, Renchao; Xu, Junjie; Liu, Mengmei; Liu, Zhengwang


    Yolk-shell microspheres with magnetic Fe3O4 cores and hierarchical copper silicate shells have been successfully synthesized by combining the versatile sol-gel process and hydrothermal reaction. Various yolk-shell microspheres with different core size and shell thickness can be readily synthesized by varying the experimental conditions. Compared to pure Fe3O4, the as-synthesized yolk-shell microspheres exhibit significantly enhanced microwave absorption properties in terms of both the maximum reflection loss value and the absorption bandwidth. The maximum reflection loss value of these yolk-shell microspheres can reach -23.5 dB at 7 GHz with a thickness of 2 mm, and the absorption bandwidths with reflection loss lower than -10 dB are up to 10.4 GHz. Owing to the large specific surface area, high porosity, and synergistic effect of both the magnetic Fe3O4 cores and hierarchical copper silicate shells, these unique yolk-shell microspheres may have the potential as high-efficient absorbers for microwave absorption applications.

  20. Synergetic effect of organic cores and inorganic shells for core/shell structured composite abrasives for chemical mechanical planarization

    Chen, Yang, E-mail: [School of Materials Science and Engineering, Changzhou University, Changzhou, Jiangsu 213164 (China); Li, Zhina [School of Materials Science and Engineering, Changzhou University, Changzhou, Jiangsu 213164 (China); Miao, Naiming [School of Mechanical Engineering, Changzhou University, Changzhou, Jiangsu 213016 (China)


    Highlights: • The damage-free polishing mechanism of core/shell composite abrasive was explored. • The organic core is help to decrease surface roughness and mechanical damages. • The inorganic shell is in favor of improving material removal rate. • The enhanced CMP behavior is due to the synergistic effect between core and shell. - Abstract: Core/shell structured organic/inorganic composite microspheres has an important potential application in efficient and damage-free chemical mechanical planarization/polishing (CMP) as a kind of novel abrasive due to its uniform non-rigid mechanical property. However, the synergistic effect of material removal between organic cores and inorganic shells of composite abrasives is ambiguous. In this work, oxide-CMP performances of various slurries, containing polystyrene (PS) spheres, solid abrasives (SiO{sub 2} or CeO{sub 2}), mixed abrasives ((PS + SiO{sub 2}) or (PS + CeO{sub 2})), core/shell composites (PS/SiO{sub 2} or PS/CeO{sub 2}), were investigated by atomic force microscopy. Experiment results indicated that the surfaces polished by composite abrasives exhibited lower surface roughness, fewer scratches as well as lower topographical variations than those by other type of abrasives. The core/shell structure of composite abrasives plays an important role in improving CMP behavior. Moreover, the organic cores are mainly beneficial to decrease surface roughness and mechanical damages, and the inorganic shells are in favor of improving material removal rate.

  1. Shell thickness matters! Energy transfer and rectification study of Au/ZnO core/shell nanoparticles.

    Haldar, Krishna Kanta; Sen, Tapasi


    In the present study we report the influence of shell thickness on fluorescence resonance energy transfer between Au/ZnO core-shell nanoparticles and Rhodamine 6G dye by steady-state and time-resolved spectroscopy and rectification behaviours. Au/ZnO core-shell nanoparticles with different shell thickness were synthesized in aqueous solution by chemically depositing zinc oxide on gold nanoparticles surface. A pronounced effect on the photoluminescence (PL) intensity and shortening of the decay time of the dye in presence of Au/ZnO core-shell nanoparticles is observed. The calculated energy transfer efficiencies from dye to Au/ZnO are 62.5%, 79.2%, 53.6% and 46.7% for 1.5nm, 3nm, 5nm and 8nm thickness of shell, respectively. Using FRET process, the calculated distances (r) are 117.8, 113.2Å 129.9Å and 136.7Å for 1.5nm, 3nm, 5nm and 8nm thick Au/ZnO core-shell nanoparticles, respectively. The distances (d) between the donor and acceptor are 71.0, 57.8, 76.2 and 81.6Å for 1.5nm, 3nm, 5nm and 8nm thick core-shell Au/ZnO nanoparticles, respectively, using the efficiency of surface energy transfer (SET). The current-voltage (I-V) curve of hybrid Au/ZnO clearly exhibits a rectifying nature and represents the n-type Schottky diode characteristics with a typical turn-on voltage of between 0.6 and 1.3V. It was found that the rectifying ratio increases from 20 to 90 with decreasing the thickness of the shell from 5nm to 3nm and with shell thickness of 8nm, electrical transport through the core-shell is similar to what is observed with pure ZnO samples nanoparticles. The results indicated that the Au/ZnO core-shell nanoparticles with an average shell thickness of 3nm exhibited the maximum energy transfer efficiencies (79.2%) and rectification (rectifying ratio 90).

  2. 7 CFR 51.2002 - Split shell.


    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Split shell. 51.2002 Section 51.2002 Agriculture... Standards for Grades of Filberts in the Shell 1 Definitions § 51.2002 Split shell. Split shell means a shell... of the shell, measured in the direction of the crack....

  3. Safety studies conducted on pecan shell fiber, a food ingredient produced from ground pecan shells

    Laurie Dolan


    Full Text Available Use of pecan shell fiber in human food is presently limited, but could increase pending demonstration of safety. In a 91-day rat study, pecan shell fiber was administered at dietary concentrations of 0 (control, 50 000, 100 000 or 150 000 ppm. There was no effect of the ingredient on body weight of males or females or food consumption of females. Statistically significant increases in food consumption were observed throughout the study in 100 000 and 150 000 ppm males, resulting in intermittent decreases in food efficiency (150 000 ppm males only that were not biologically relevant. All animals survived and no adverse clinical signs or functional changes were attributable to the test material. There were no toxicologically relevant changes in hematology, clinical chemistry or urinalysis parameters or organ weights in rats ingesting pecan shell fiber. Any macroscopic or microscopic findings were incidental, of normal variation and/or of minimal magnitude for test substance association. Pecan shell fiber was non-mutagenic in a bacterial reverse mutation test and non-clastogenic in a mouse peripheral blood micronucleus test. Based on these results, pecan shell fiber has an oral subchronic (13-week no observable adverse effect level (NOAEL of 150 000 ppm in rats and is not genotoxic at the doses analyzed.

  4. Locomotor function of forelimb protractor and retractor muscles of dogs: evidence of strut-like behavior at the shoulder.

    Carrier, David R; Deban, Stephen M; Fischbein, Timna


    The limbs of running mammals are thought to function as inverted struts. When mammals run at constant speed, the ground reaction force vector appears to be directed near the point of rotation of the limb on the body such that there is little or no moment at the joint. If this is true, little or no external work is done at the proximal joints during constant-speed running. This possibility has important implications to the energetics of running and to the coupling of lung ventilation to the locomotor cycle. To test if the forelimb functions as an inverted strut at the shoulder during constant-speed running and to characterize the locomotor function of extrinsic muscles of the forelimb, we monitored changes in the recruitment of six muscles that span the shoulder (the m. pectoralis superficialis descendens, m. pectoralis profundus, m. latissimus dorsi, m. omotransversarius, m. cleidobrachialis and m. trapezius) to controlled manipulations of locomotor forces and moments in trotting dogs (Canis lupus familiaris Linnaeus 1753). Muscle activity was monitored while the dogs trotted at moderate speed (approximately 2 m s(-1)) on a motorized treadmill. Locomotor forces were modified by (1) adding mass to the trunk, (2) inclining the treadmill so that the dogs ran up- and downhill (3) adding mass to the wrists or (4) applying horizontally directed force to the trunk through a leash. When the dogs trotted at constant speed on a level treadmill, the primary protractor muscles of the forelimb exhibited activity during the last part of the ipsilateral support phase and the beginning of swing phase, a pattern that is consistent with the initiation of swing phase but not with active protraction of the limb during the beginning of support phase. Results of the force manipulations were also consistent with the protractor muscles initiating swing phase and contributing to active braking via production of a protractor moment on the forelimb when the dogs decelerate. A similar

  5. Blended Isogeometric Shells


    possibilities that heretofore have not been investigated, namely, “rigid bodies” [7]. Another need for the use of these techniques is in multi-patch NURBS meshes... techniques is completely satisfactory in all cases. Even if they can be used successfully in certain situations they can give rise to reduced critical...condition which is violated at the patch boundaries. The C0 boundaries between patches behave like piano hinges for thin shell formulations, and

  6. Off-Shell Supersymmetry

    Ho, Chiu Man; Okada, Nobuchika


    Supersymmetry does not dictate the way we should quantize the fields in the supermultiplets, and so we have the freedom to quantize the Standard Model (SM) particles and their superpartners differently. We propose a generalized quantization scheme under which a particle can only appear off-shell, while its contributions to quantum corrections are exactly the same as those in the usual quantum field theory. We apply this quantization scheme solely to the sparticles in the $R$-parity preserving...

  7. Synthesis and characterization of Silica/polyvinyl imidazole/H2PO4-core-shell nanoparticles as recyclable adsorbent for efficient scavenging of Sm(III) and Dy(III) from water.

    Ettehadi Gargari, Jafar; Sid Kalal, Hossein; Shakeri, Alireza; Khanchi, Alireza


    In this study, we used Silica/polyvinyl imidazole core-shell nanoparticles impregnated with sodium dihydrogen phosphate (SiO2/PVI/H2PO4(-) NPs) for adsorption of samarium and dysprosium ions from aqueous solutions. The effects of the pH, adsorbent dose, contact time, and initial concentration of the adsorbate on the Core-shell nanoparticles adsorption capacity have been studied. The pH value for maximum removal of Sm (III) and Dy (III) on the core-shell nanoparticles surface were found to be 4. The saturated capacity of SiO2/PVI/H2PO4(-) NPs was up to 160mg.g(-1) and 150mg.g(-1)at 25°C for Sm (III) and Dy (III) ions respectively. The obtained uptake data were analyzed by the Langmuir and Freundlich equations using a linearized correlation coefficient at room temperature. The Freundlich isotherm was found to fit well with the equilibrium data. The adsorption kinetics could be modeled by a pseudo-second-order rate expression. Thermodynamic investigation revealed the adsorption process of the studied ions is entropy driven. Furthermore, the performance of regeneration and reutilization were studied. The adsorbed Sm (III) and Dy (III) can be desorbed by 0.5mol/L HCl, with the desorption percentage of 90% for Sm (III) and Dy (III). After five adsorption-desorption cycles, the adsorption capacity shows a slight decrease (about 15%), implying that the SiO2/PVI/H2PO4(-) NPs can be used as an effective adsorbent for the removal and recovery of Sm(III) and Dy(III) from aqueous solution. The colloid stability of the SiO2/PVI/H2PO4(-) NPs was investigated by dynamic light scattering measurements. The SiO2/PVI/H2PO4(-) NPs are stable in adsorption media after five adsorption - desorption cycles. The high stability of SiO2/PVI/H2PO4(-) NPs can be attributed to steric stabilization by polyvinyl imidazole adsorbed on SiO2 nanoparticle surfaces. Copyright © 2017 Elsevier Inc. All rights reserved.

  8. Association of Skin Thickness With Alar Base Reduction in Patients Undergoing Lateral Crural Repositioning and Strut Grafting.

    Ilhan, A Emre; Sozen, Tevfik; Caypinar Eser, Basak; Cengiz, Betul


    Knowing the operation plan is important for rhinoplasty surgeons to prevent unpredictable results. To investigate the frequency of alar base resection in patients with different skin thickness who underwent lateral crural repositioning and lateral crural strut graft and to evaluate the results in the context of the current literature. This retrospective case series study included 621 patients who underwent primary open septorhinoplasty by the same surgeon between January 1, 2012, and June 30, 2015. From the surgical notes, operation type (lateral crural repositioning [LCrep] with lateral crural strut grafting [LCSG] and with or without alar base resection) and skin type were recorded. Study participants' skin types were determined intraoperatively and divided into 3 groups: (1) thick skin (the tip definition was limited by skin thickness and subcutaneous tissue), (2) thin skin (the tip cartilage was visible and could be observed despite overlying soft tissue and skin), and (3) normal skin (the tip cartilage during the procedure had no effect on the tip definition). Of the 621 patients in the study, 95 (15.3%) were men and 526 (84.7%) were women. Lateral crural repositioning with LCSG was performed in 319 surgical procedures (51.4%), and alar base reduction was performed in 329 (53.0%). The rate of alar base resection differed significantly on the basis of whether LCrep with LCSG was performed (odds ratio [OR], 1.82; 95% CI, 1.32-2.50; P alar base resection associated with LCrep with LCSG (OR, 2.034; 95% CI, 0.912-4.539; P = .08). In patients with thick skin, a significant difference in the frequency of alar base resection was associated with the application of LCrep with LCSG (OR, 1.995; 95% CI, 1.228-3.241; P = .005). In patients with normal skin, LCrep with LCSG had no significant association with the frequency of alar base resection (OR, 1.557; 95% CI, 0.930-2.607; P = .09). The necessity of alar base reduction after LCrep with LCSG is greater in

  9. Combined use of extensively porous coated femoral components with onlay cortical strut allografts in revision of Vancouver B2 and B3 periprosthetic femoral fractures

    WU Hao-bo; YAN Shi-gui; WU Li-dong; HE Rong-xin; WANG Xiang-hua; DAI Xue-song


    Background Periprosthetic femoral fractures following total hip arthroplasty are getting more prevalent.The aim of this study was to evaluate the clinical results of combined use of uncemented extensively porous coated femoral components with onlay cortical strut allografts in revision of Vancouver type B2 and B3 periprosthetic femoral fractures.Methods Thirteen hips after total hip arthroplasty in 13 patients who suffered a Vancouver B2 or B3 periprosthetic fracture were treated with an uncemented extensively porous coated femoral component combined with onlay cortical strut allografts.Each patient was assigned a Harris hip score,and a visual analog scale(VAS)score for pain and satisfaction.Radiographs were examined for component stability,fracture site and allograft-host union and allograft reconstruction.Results At an average of 5.3-year follow-up,no patient required repeat revision.The average Harris hip score was(71.8±6.3)points,the pain VAS score was(16.6±4.3)points,and the patient satisfaction VAS score was(81.5±5.7)points.Radiographic examination showed no detectable loosening of the prostheses,and 12 cases were presented fixation by osseointegration and the other one was stable fibrous ingrown fixation.All fractures united for(5.2±1.4)months in average.And all onlay strut allografts united to host bone for about(11.5±2.6)months.Conclusions Combined use of uncemented,long stemmed,extensively porous coated implant with cortical onlay strut allografts can achieve good clinic results and high rate of union for both fracture site and allograft-host bone junction.This technique could be used routinely to augment fixation and healing of Vancouver B2 and B3 periprosthetic fractures.

  10. Energy Migration Upconversion in Ce(III)-Doped Heterogeneous Core-Shell-Shell Nanoparticles.

    Chen, Xian; Jin, Limin; Sun, Tianying; Kong, Wei; Yu, Siu Fung; Wang, Feng


    One major challenge in upconversion research is to develop new materials and structures to expand the emission spectrum. Herein, a heterogeneous core-shell-shell nanostructure of NaYbF4 :Gd/Tm@NaGdF4 @CaF2 :Ce is developed to realize efficient photon upconversion in Ce(3+) ions through a Gd-mediated energy migration process. The design takes advantage of CaF2 host that reduces the 4f-5d excitation frequency of Ce(3+) to match the emission line of Gd(3+) . Meanwhile, CaF2 is isostructural with NaGdF4 and can form a continuous crystalline lattice with the core layer. As a result, effective Yb(3+) → Tm(3+) → Gd(3+) → Ce(3+) energy transfer can be established in a single nanoparticle. This effect enables efficient ultraviolet emission of Ce(3+) following near infrared excitation into the core layer. The Ce(3+) upconversion emission achieved in the core-shell-shell nanoparticles features broad bandwidth and long lifetime, which offers exciting opportunities of realizing tunable lasing emissions in the ultraviolet spectral region. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. 基于MVC设计模式的Struts框架的设计与实现%The Design and Implementation of Struts Framework Based on MVC Design Pattern

    冯艳茹; 苏文芝


    Struts框架是MVC设计模式的实现,通过在Web页面中使用J2EE中规范的标签,实现页面表示层和事务数据层的分离,增加了耦合性,提高了代码的可重用性。最后,以一个使用 Struts框架构建的Web应用程序为例,来说明Struts框架如何实现MVC设计模式的。%The Struts framework is a realization of MVC design pattern, By using J2ee tags in web pages,the expression layer and logic data layer of the pages were separated to increase the coupling, increase the code reusability.finally, In a Struts framework using the Web application as an example, to illustrate how the Struts framework to realize MVC design pattern.

  12. Shell model calculations of 109Sb in the sdgh shell

    Dikmen, E.; Novoselsky, A.; Vallieres, M.


    The energy spectra of the antimony isotope 109Sb in the sdgh shell are calculated in the nuclear shell model approach by using the CD-Bonn nucleon-nucleon interaction. The modified Drexel University parallel shell model code (DUPSM) was used for the calculations with maximum Hamiltonian dimension of 762 253 of 5.14% sparsity. The energy levels are compared to the recent experimental results. The calculations were done on the Cyborg Parallel Cluster System at Drexel University.

  13. Preparation of n-tetradecane-containing microcapsules with different shell materials by phase separation method

    Yang, Rui [Department of Chemical Engineering, Tsinghua University, Beijing (China); Zhang, Yan; Zhang, Qingwu [Department of Chemical Engineering, China University of Mining and Technology, Beijing (China); Wang, Xin; Zhang, Yinping [Department of Building Science, Tsinghua University, Beijing (China)


    Microcapsules for thermal energy storage and heat-transfer enhancement have attracted great attention. Microencapsulation of n-tetradecane with different shell materials was carried out by phase separation method in this paper. Acrylonitrile-styrene copolymer (AS), acrylonitrile-styrene-butadiene copolymer (ABS) and polycarbonate (PC) were used as the shell materials. The structures, morphologies and the thermal capacities of the microcapsules were characterized using Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and differential scanning calorimetry (DSC). The ternary phase diagrams showed the potential encapsulation capabilities of the three shell materials. The effects of the shell/core ratio and the molecular weight of the shell material on the encapsulation efficiency and the thermal capacity of the microcapsules were also discussed. Microcapsules with melting enthalpy > 100 J/g, encapsulation efficiency 66-75%, particle size<1 {mu}m were obtained for all three shell materials. (author)

  14. Multi Objective Robust Active Vibration Control for Flexure Jointed Struts of Stewart Platforms via H∞ and μ Synthesis

    Liu Lei; Wang Benli


    Active vibration control is needed for future space telescopes, space laser communication and other precision sensitive payloads which require ultra-quiet environments. A Stewart platform based hybrid isolator with 6 hybrid struts is the effective system for ac- tive/passive vibration isolation over 5-250 Hz band. Using an identification transfer matrix of the Stewart platform, the coupling analysis of six channels is provided. A dynamics model is derived, and the rigid mode is removed to keep the signal of pointing control. Multi objective robust H∞ and μ synthesis strategies, based on singular values and structured singular values respectively, are presented, which simultaneously satisfy the low frequency pointing and high frequency disturbance rejection requirements and take account of the model uncertainty, parametric uncertainty and sensor noise. Then, by performing robust stability test, it is shown that the two controllers are robust to the uncertainties, the robust stability margin of H∞ controller is less than that of μ controller, but the order of μ controller is higher than that of H∞ controller, so the balanced controller reduction is provided. Additionally, the μ controller is compared with a PI controller. The time domain simulation of the μ controller indicates that the two robust control strategies are effective for keeping the pointing command and isolating the harmonic and stochastic disturbances.

  15. Thermal investigation of an internally cooled strut injector for scramjet application at moderate and hot gas conditions

    Dröske, Nils C.; Förster, Felix J.; Weigand, Bernhard; von Wolfersdorf, Jens


    In this paper, we present a combined experimental and numerical approach to assess the thermal loads and the cooling mechanism of an internally cooled strut injector for a supersonic combustion ramjet. Infrared measurements of the injector surface are conducted at a moderate external flow temperature. In addition, the main flow field is investigated with the LITA technique. Main features of the cooling mechanism are identified based on experimental data. However, a full evaluation can only be obtained using a complex, conjugate CFD simulation, which couples the external and internal flow fields to the heat conduction inside the injector body. Furthermore, numerical simulations are also presented for hot gas conditions corresponding to combustion experiments. Both hydrogen, which would be used as fuel for flight tests, and air are considered as coolants. While the main features of the cooling mechanism will be shown to remain unchanged, the combustor wall temperature is found to have a significant influence on the cooling. This emphasizes the importance and the usefulness of such complex conjugate numerical simulations.

  16. Multi-shell effective interactions

    Tsunoda, Naofumi; Hjorth-Jensen, Morten; Otsuka, Takaharu


    Background: Effective interactions, either derived from microscopic theories or based on fitting selected properties of nuclei in specific mass regions, are widely used inputs to shell-model studies of nuclei. Until recently, most shell-model calculations have been confined to a single oscillator shell. Recent interest in nuclei away from the stability line, requires however larger shell-model spaces. Since the derivation of microscopic effective interactions has been limited to degenerate model spaces, there are both conceptual and practical limits to present shell-model calculations that utilize such interactions. Purpose: The aim of this work is to present a novel microscopic method to calculate effective interactions for the nuclear shell model. Its main difference from existing theories is that it can be applied not only to degenerate model spaces but also to non-degenerate model spaces. Methods: The formalism is presented in the form of many-body perturbation theory based on the recently developed Exten...

  17. Shell Biorefinery: Dream or Reality?

    Chen, Xi; Yang, Huiying; Yan, Ning


    Shell biorefinery, referring to the fractionation of crustacean shells into their major components and the transformation of each component into value-added chemicals and materials, has attracted growing attention in recent years. Since the large quantities of waste shells remain underexploited, their valorization can potentially bring both ecological and economic benefits. This Review provides an overview of the current status of shell biorefinery. It first describes the structural features of crustacean shells, including their composition and their interactions. Then, various fractionation methods for the shells are introduced. The last section is dedicated to the valorization of chitin and its derivatives for chemicals, porous carbon materials and functional polymers. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Wrinkling of Pressurized Elastic Shells

    Vella, Dominic


    We study the formation of localized structures formed by the point loading of an internally pressurized elastic shell. While unpressurized shells (such as a ping-pong ball) buckle into polygonal structures, we show that pressurized shells are subject to a wrinkling instability. We study wrinkling in depth, presenting scaling laws for the critical indentation at which wrinkling occurs and the number of wrinkles formed in terms of the internal pressurization and material properties of the shell. These results are validated by numerical simulations. We show that the evolution of the wrinkle length with increasing indentation can be understood for highly pressurized shells from membrane theory. These results suggest that the position and number of wrinkles may be used in combination to give simple methods for the estimation of the mechanical properties of highly pressurized shells. © 2011 American Physical Society.

  19. Catalytic Polymer Multilayer Shell Motors for Separation of Organics.

    Lin, Zhihua; Wu, Zhiguang; Lin, Xiankun; He, Qiang


    A catalytic polymer multilayer shell motor has been developed, which effects fast motion-based separation of charged organics in water. The shell motors are fabricated by sputtering platinum onto the exposed surface of silica templates embedded in Parafilm, followed by layer-by-layer assembly of polyelectrolyte multilayers to the templates. The catalytic shell motors display high bubble propulsion with speeds of up to 260 μm s(-1) (13 body lengths per second). Moreover, the polyelectrolyte multilayers assembled at high pH (pH>9.0) adsorb approximately 89% of dye molecules from water, owing to the electrostatic interaction between the positively charged polymers and the anionic dye molecules, and subsequently release them at neutral pH in a microfluidic device. The efficient propulsion coupled with the effective adsorption behavior of the catalytic shell motors in a microfluidic device results in accelerated separation of organics in water and thus holds considerable promise for water analysis.

  20. A Comparative Study of Cellulose Agricultural Wastes (Almond Shell, Pistachio Shell, Walnut Shell, Tea Waste And Orange Peel for Adsorption of Violet B Dye from Aqueous Solutions

    Saeedeh Hashemian


    Full Text Available Adsorption of violet B azo dye from aqueous solutions was studied by different cellulose agriculturalwaste materials (almond shell (AS, pistachio shell (PS, walnut shell (WS, Tea waste (TW and orange peel (OP. Cellulose agricultural waste sorbents characterized by FTIR and SEM methods. The effects of different parameters such as contact time, pH, adsorbent dosage and initial dye concentration were studied.Maximum removal of dye was obtained at contact time of 90 min and pH 11.The adsorption of violet B was fitted by pseudo-second-order kinetic model.The Langmuir isotherm model was better fitted than Freundlichmodel. The results showed that the adsorption efficiency of violet B by cellulose agricultural waste materials is as followed: Almond shell > Orange peel > Pistachio shell > Tea waste> Walnut shell.The maximum adsorption capacity was obtained 96, 82, 71.4, 55.5 and 48.7 mg g−1 for AS, OP, PS, TW and WS, respectively.

  1. The notes on thin shells

    Iofa, Mikhail Z


    Geometry of the spacetime with a spherical shell embedded in it is studied in two coordinate systems - in Kodama-Schwarzschild coordinates and in Gaussian normal coordinates. We consider transformations between the coordinate systems as in the 4D spacetime so as at the surface $\\S$ swept in the spacetime by the spherical shell. Extrinsic curvatures of the surface swept by the shell are calculated in both coordinate systems. Applications to the Israel junction conditions are discussed.

  2. Shell effects in nuclear magnetization

    Kondratyev, V.N.; Maruyama, Toshiki; Chiba, Satoshi [Advanced Science Research Center, Japan Atomic Energy Research Institute, Tokai, Ibaraki (Japan)


    The magnetization of nuclei in strong magnetic fields associated with magnetars' is considered within the shell model. It is demonstrated that the magnetic field gives rise to a phase-shift of the shell-oscillations in nuclear masses shifting significantly the nuclear magic numbers of the iron region towards smaller mass numbers. Shell-effects are found to result in anomalies of the nuclear magnetization. Such anomalies resemble the behavior associated with a phase transition. (author)

  3. Dual role of circulating endothelial progenitor cells in stent struts endothelialisation and neointimal regrowth: A substudy of the IN-PACT CORO trial

    De Maria, Giovanni Luigi [Institute of Cardiology, Catholic University of the Sacred Heart, Rome (Italy); Porto, Italo, E-mail: [Institute of Cardiology, Catholic University of the Sacred Heart, Rome (Italy); Interventional Cardiology Unit, San Donato Hospital, Arezzo (Italy); Burzotta, Francesco; Brancati, Marta Francesca; Trani, Carlo; Pirozzolo, Giancarlo; Leone, Antonio Maria; Niccoli, Giampaolo [Institute of Cardiology, Catholic University of the Sacred Heart, Rome (Italy); Prati, Francesco [Department of Interventional Cardiology, San Giovanni Hospital, Rome (Italy); Crea, Filippo [Institute of Cardiology, Catholic University of the Sacred Heart, Rome (Italy)


    Background: Endothelialisation is a crucial event after percutaneous coronary intervention (PCI). Endothelial progenitor cells (EPCs) are bone marrow derived elements with reparative properties. We aimed to assess the relationship between circulating EPC levels and stent neointimal hyperplasia (NIH) using frequency domain optical coherence tomography (FD-OCT). Methods: Patients undergoing elective PCI to native vessels and randomised to bare metal stent (BMS) alone versus BMS plus drug coated balloon (DCB) were included. At six months, angiographic follow-up and FD-OCT were performed to measure percentage neointimal hyperplasia volume obstruction (%NIHV), and percentage of uncovered stent struts (%US). Venous blood samples were obtained before the procedure and at six months to detect CD34+CD45dimKDR + EPC levels. Results: Twenty patients were enrolled. A significant relationship was observed between baseline EPC levels and %NIHV (R: 0.63, p: 0.03) and %US (R: − 0.56, p: 0.01) at follow-up. Both EPC levels and DCB use were independently related to %NIHV (β: 0.55; p < 0.001 and β: − 0.51; p: 0.001, respectively), while only EPC levels were independently associated to %US (β: − 0.52; p: 0.01). Higher %NIHV (p: 0.004) and lower %US (p: 0.005) were observed in patients with stable or increasing EPC level. Conclusion: Our study shows a relationship between EPC levels and stent strut coverage, supporting a dual role for these cells in favouring stent endothelialisation but also NIH growth. - Highlights: • Substudy of IN-PACT CORO trial comparing, by adoption of optical coherence tomography, the amount of neointimal growth and stent struts coverage at six months of follow up, in elective patients randomised to conventional PCI with bare metal stent implantation (BMS group) or to stent implantation with pre or postdilation with a drug coated balloon (BMS + DCB group) • Lower neointimal regrowth observed in BMS + DCB group • First in vivo demonstration that

  4. Variable Geometry Aircraft Wing Supported by Struts And/Or Trusses

    Melton, John E. (Inventor); Dudley, Michael R. (Inventor)


    The present invention provides an aircraft having variable airframe geometry for accommodating efficient flight. The aircraft includes an elongated fuselage, an oblique wing pivotally connected with said fuselage, a wing pivoting mechanism connected with said oblique wing and said fuselage, and a brace operably connected between said oblique wing and said fuselage. The present invention also provides an aircraft having an elongated fuselage, an oblique wing pivotally connected with said fuselage, a wing pivoting mechanism connected with said oblique wing and said fuselage, a propulsion system pivotally connected with said oblique wing, and a brace operably connected between said propulsion system and said fuselage.

  5. Plate shell structures of glass

    Bagger, Anne

    to their curved shape. A plate shell structure maintains a high stiffness-to-weight ratio, while facilitating the use of plane structural elements. The study focuses on using laminated glass panes for the load bearing facets. Various methods of generating a plate shell geometry are suggested. Together with Ghent......, such as facet size, imperfections, and connection characteristics. The critical load is compared to that of a similar, but smoothly curved, shell structure. Based on the investigations throughout the study, a set of guidelines for the structural design of plate shells of glass is proposed....

  6. 7 CFR 51.2289 - Shell.


    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Shell. 51.2289 Section 51.2289 Agriculture Regulations... Standards for Shelled English Walnuts (Juglans Regia) Definitions § 51.2289 Shell. Shell means the outer shell and/or the woody partition from between the halves of the kernel, and any fragments of either....

  7. A study on an efficient prediction of welding deformation for T-joint laser welding of sandwich panel Part II : Proposal of a method to use shell element model

    Kim Jae Woong


    Full Text Available I-core sandwich panel that has been used more widely is assembled using high power CO₂laser welding. Kim et al. (2013 proposed a circular cone type heat source model for the T-joint laser welding between face plate and core. It can cover the negative defocus which is commonly adopted in T-joint laser welding to provide deeper penetration. In part I, a volumetric heat source model is proposed and it is verified thorough a comparison of melting zone on the cross section with experiment results. The proposed model can be used for heat transfer analysis and thermal elasto-plastic analysis to predict welding deformation that occurs during laser welding. In terms of computational time, since the thermal elasto-plastic analysis using 3D solid elements is quite time consuming, shell element model with multi-layers have been employed instead. However, the conventional layered approach is not appropriate for the application of heat load at T-Joint. This paper, Part II, suggests a new method to arrange different number of layers for face plate and core in order to impose heat load only to the face plate.

  8. A study on an efficient prediction of welding deformation for T-joint laser welding of sandwich panel Part II : Proposal of a method to use shell element model

    Kim, Jae Woong; Jang, Beom Seon; Kang, Sung Wook


    I-core sandwich panel that has been used more widely is assembled using high power CO-laser welding. Kim et al. (2013) proposed a circular cone type heat source model for the T-joint laser welding between face plate and core. It can cover the negative defocus which is commonly adopted in T-joint laser welding to provide deeper penetration. In part I, a volumetric heat source model is proposed and it is verified thorough a comparison of melting zone on the cross section with experiment results. The proposed model can be used for heat transfer analysis and thermal elasto-plastic analysis to predict welding deformation that occurs during laser welding. In terms of computational time, since the thermal elasto-plastic analysis using 3D solid elements is quite time consuming, shell element model with multi-layers have been employed instead. However, the conventional layered approach is not appropriate for the application of heat load at T-Joint. This paper, Part II, suggests a new method to arrange different number of layers for face plate and core in order to impose heat load only to the face plate.

  9. Comparative study on thermal performance of natural draft cooling towers with finned shells

    Goodarzi, Mohsen [Bu-Ali Sina Univ., Hamedan (Iran, Islamic Republic of). Dept. of Mechanical Engineering


    The cooling efficiency of natural draft cooling towers under crosswind condition should be improved. In the present research work three different externally finned shells were considered for a typical natural draft cooling tower to investigate the cooling improvement. They were numerically simulated under normal and crosswind conditions. Numerical results show that twisting four fin plates over the tower shell along the 45 peripheral angle, could improve the cooling efficiency up to 6.5 %. Because of the periodic shape of the fin plates, the cooling efficiency of the cooling tower with finned shell is less sensitive to the change of wind.

  10. Biomechanics of turtle shells: how whole shells fail in compression.

    Magwene, Paul M; Socha, John J


    Turtle shells are a form of armor that provides varying degrees of protection against predation. Although this function of the shell as armor is widely appreciated, the mechanical limits of protection and the modes of failure when subjected to breaking stresses have not been well explored. We studied the mechanical properties of whole shells and of isolated bony tissues and sutures in four species of turtles (Trachemys scripta, Malaclemys terrapin, Chrysemys picta, and Terrapene carolina) using a combination of structural and mechanical tests. Structural properties were evaluated by subjecting whole shells to compressive and point loads in order to quantify maximum load, work to failure, and relative shell deformations. The mechanical properties of bone and sutures from the plastral region of the shell were evaluated using three-point bending experiments. Analysis of whole shell structural properties suggests that small shells undergo relatively greater deformations before failure than do large shells and similar amounts of energy are required to induce failure under both point and compressive loads. Location of failures occurred far more often at sulci than at sutures (representing the margins of the epidermal scutes and the underlying bones, respectively), suggesting that the small grooves in the bone created by the sulci introduce zones of weakness in the shell. Values for bending strength, ultimate bending strain, Young's modulus, and energy absorption, calculated from the three-point bending data, indicate that sutures are relatively weaker than the surrounding bone, but are able to absorb similar amounts of energy due to higher ultimate strain values. Copyright © 2012 Wiley Periodicals, Inc.

  11. Sensitized solar cells with colloidal PbS-CdS core-shell quantum dots

    Lai, Lai-Hung; Protesescu, Loredana; Kovalenko, Maksym V.; Loi, Maria A.


    We report on the fabrication of PbS-CdS (core-shell) quantum dot (QD)-sensitized solar cells by direct adsorption of core-shell QDs on mesoporous TiO2 followed by 3-mercaptopropionic acid ligand exchange. PbS-CdS QD-sensitized solar cells show 4 times higher efficiency with respect to solar cells se

  12. Shell-side dispersion coefficients in a rectangular cross-flow hollow fibre membrane module

    Dindore, V. Y.; Cents, A. H. G.; Brilman, D. W. F.; Versteeg, G. F.


    Membrane processes utilizing hollow fibre membrane modules are gaining increased interest in many industrial applications. However, these modules suffer from shell-side maldistribution and bypassing which results in a loss in efficiency. The shell-side mass transfer performance of these membrane mod

  13. Shell-side dispersion coefficients in a rectangular cross-flow hollow fibre membrane module

    Dindore, V. Y.; Cents, A. H. G.; Brilman, D. W. F.; Versteeg, G. F.


    Membrane processes utilizing hollow fibre membrane modules are gaining increased interest in many industrial applications. However, these modules suffer from shell-side maldistribution and bypassing which results in a loss in efficiency. The shell-side mass transfer performance of these membrane

  14. Sensitized solar cells with colloidal PbS-CdS core-shell quantum dots

    Lai, Lai-Hung; Protesescu, Loredana; Kovalenko, Maksym V.; Loi, Maria A.


    We report on the fabrication of PbS-CdS (core-shell) quantum dot (QD)-sensitized solar cells by direct adsorption of core-shell QDs on mesoporous TiO2 followed by 3-mercaptopropionic acid ligand exchange. PbS-CdS QD-sensitized solar cells show 4 times higher efficiency with respect to solar cells

  15. Shell Trumpets from Western Mexico

    Robert Novella


    Full Text Available Marine shells have been used as musical instruments in almost all parts of the world (Izikowitz 1935, including Mesoamerica, where large univalves, also called conch shells in the literature, had a utilitarian function as trumpets. Their use is well documented in most cultural areas of Mesoamerica, as in Western Mexico, through their various occurrences in archaeological contexts and museums collections.

  16. Shell model and spectroscopic factors

    Poves, P. [Madrid Univ. Autonoma and IFT, UAM/CSIC, E-28049 (Spain)


    In these lectures, I introduce the notion of spectroscopic factor in the shell model context. A brief review is given of the present status of the large scale applications of the Interacting Shell Model. The spectroscopic factors and the spectroscopic strength are discussed for nuclei in the vicinity of magic closures and for deformed nuclei. (author)

  17. Controlled Isotropic and Anisotropic Shell Growth in β-NaLnF4 Nanocrystals Induced by Precursor Injection Rate.

    Fischer, Stefan; Swabeck, Joseph K; Alivisatos, A Paul


    Precise morphology and composition control is vital for designing multifunctional lanthanide-doped core/shell nanocrystals. Herein, we report controlled isotropic and anisotropic shell growth techniques in hexagonal sodium rare-earth tetrafluoride (β-NaLnF4) nanocrystals by exploiting the kinetics of the shell growth. A drastic change of the shell morphology was observed by changing the injection rate of the shell precursors while keeping all other reaction conditions constant. We obtained isotropic shell growth for fast sequential injection and a preferred growth of the shell layers along the crystal's c-axis [001] for slow dropwise injection. Using this slow shell growth technique, we have grown rod-like shells around different almost spherical core nanocrystals. Bright and efficient upconversion was measured for both isotropic and rod-like shells around β-NaYF4 nanocrystals doped with Yb(3+)/Er(3+) and Yb(3+)/Tm(3+). Photoluminescence upconversion quantum yield and lifetime measurements reveal the high quality of the core/shell nanocrystal. Furthermore, multishell rod-like nanostructures have been prepared with optically active cores and tips separated by an inert intermediate shell layer. The controlled anisotropic shell growth allows the design of new core/multishell nanostructures and enables independent investigations of the chemistry and physics of different nanocrystal facets.

  18. Numerical Studies on the Performance of Scramjet Combustor with Alternating Wedge-Shaped Strut Injector

    Choubey, Gautam; Pandey, K. M.


    Numerical analysis of the supersonic combustion and flow structure through a scramjet engine at Mach 7 with alternating wedge fuel injection and with three angle of attack (α=-3°, α=0°, α=3°) have been studied in the present research article. The configuration used here is slight modification of the Rabadan et al. scramjet model. Steady two dimensional (2D) Reynolds-averaged Navier-Stokes (RANS) simulation and Shear stress transport (SST) based on k-ω turbulent model is used to predict the shock structure and combustion phenomenon inside the scramjet combustor. All the simulations are done by using Ansys 14-Fluent code. The combustion model used here is the combination of eddy dissipation and finite rate chemistry models since this model avoids Arrhenius calculations in which reaction rates are controlled by turbulence. Present results show that the geometry with negative angle of attack (α=-3°) have lowest ignition delay and it improves the performance of scramjet combustor as compared to geometry with α=0°, α=3°. The combustion phenomena and efficiency is also found to be stronger and highest in case of α=-3°.

  19. Biomineralisation in Mollusc shells

    Dauphin, Y.; Cuif, J. P.; Salomé, M.; Williams, C. T.


    The main components of Mollusc shells are carbonate minerals: calcite and aragonite. ACC is present in larval stages. Calcite and aragonite can be secreted simultaneously by the mantle. Despite the small number of varieties, the arrangement of the mineral components is diverse, and dependant upon the taxonomy. They are also associated with organic components much more diverse, the diversity of which reflects the large taxonomic diversity. From TGA analyses, the organic content (water included) is high (>5% in some layers). The biomineralisation process is not a passive precipitation process, but is strongly controlled by the organism. The biological-genetic control is shown by the constancy of the arrangement of the layers, the mineralogy and the microstructure in a given species. Microstructural units (i.e. tablets, prisms etc.) have shapes that do not occur in non-biogenic counterparts. Nacreous tablets, for example, are flattened on their crystallographic c axis, which is normally the axis of maximum growth rate for non-biogenic aragonite. Morever, their inner structure is species-specific: the arrangements of nacreous tablets in Gastropoda - Cephalopoda, and in Bivalvia differ, and the inner arrangement of the nacreous tablets is different in ectocochlear and endocochlear Cephalopoda. The organic-mineral ratios also differ in the various layers of a shell. Differences in chemical composition also demonstrates the biological-genetic control: for example, aragonite has a low Sr content unknown in non-biogenic samples; two aragonitic layers in a shell have different Sr and Mg contents, S is higher in calcitic layers. Decalcification releases soluble (SOM) and insoluble (IOM) organic components. Insoluble components form the main part of the intercrystalline membranes, and contain proteins, polysaccharides and lipids. Soluble phases are present within the crystals and the intercrystalline membranes. These phases are composed of more or less glycosylated proteins

  20. Multistage process for the production of bioethanol from almond shell.

    Kacem, Imen; Koubaa, Mohamed; Maktouf, Sameh; Chaari, Fatma; Najar, Taha; Chaabouni, Moncef; Ettis, Nadia; Ellouz Chaabouni, Semia


    This work describes the feasibility of using almond shell as feedstock for bioethanol production. A pre-treatment step was carried out using 4% NaOH for 60min at 121°C followed by 1% sulfuric acid for 60min at 121°C. Enzymatic saccharification of the pre-treated almond shell was performed using Penicillium occitanis enzymes. The process was optimized using a hybrid design with four parameters including the incubation time, temperature, enzyme loads, and polyethylene glycol (PEG) concentration. The optimum hydrolysis conditions led to a sugar yield of 13.5%. A detoxification step of the enzymatic hydrolysate was carried out at pH 5 using 1U/ml of laccase enzyme produced by Polyporus ciliatus. Fermenting efficiency of the hydrolysates was greatly improved by laccase treatment, increasing the ethanol yield from 30% to 84%. These results demonstrated the efficiency of using almond shell as a promising source for bioethanol production.

  1. Computational investigation of longitudinal diffusion, eddy dispersion, and trans-particle mass transfer in bulk, random packings of core-shell particles with varied shell thickness and shell diffusion coefficient.

    Daneyko, Anton; Hlushkou, Dzmitry; Baranau, Vasili; Khirevich, Siarhei; Seidel-Morgenstern, Andreas; Tallarek, Ulrich


    In recent years, chromatographic columns packed with core-shell particles have been widely used for efficient and fast separations at comparatively low operating pressure. However, the influence of the porous shell properties on the mass transfer kinetics in core-shell packings is still not fully understood. We report on results obtained with a modeling approach to simulate three-dimensional advective-diffusive transport in bulk random packings of monosized core-shell particles, covering a range of reduced mobile phase flow velocities from 0.5 up to 1000. The impact of the effective diffusivity of analyte molecules in the porous shell and the shell thickness on the resulting plate height was investigated. An extension of Giddings' theory of coupled eddy dispersion to account for retention of analyte molecules due to stagnant regions in porous shells with zero mobile phase flow velocity is presented. The plate height equation involving a modified eddy dispersion term excellently describes simulated data obtained for particle-packings with varied shell thickness and shell diffusion coefficient. It is confirmed that the model of trans-particle mass transfer resistance of core-shell particles by Kaczmarski and Guiochon [42] is applicable up to a constant factor. We analyze individual contributions to the plate height from different mass transfer mechanisms in dependence of the shell parameters. The simulations demonstrate that a reduction of plate height in packings of core-shell relative to fully porous particles arises mainly due to reduced trans-particle mass transfer resistance and transchannel eddy dispersion. Copyright © 2015 Elsevier B.V. All rights reserved.

  2. Plate shell structures of glass

    Bagger, Anne

    . This modelling technique is used to model a plate shell structure with a span of 11.5 meters in the FE software \\textsc{Abaqus}. The structure is analyzed with six different connection details with varying stiffness characteristics, to investigate the influence of these characteristics on the structural effects...... University, a script has been developed for an automated generation of a given plate shell geometry and a corresponding finite element (FE) model. A suitable FE modelling technique is proposed, suggesting a relatively simple method of modelling the connection detail's stiffness characteristics....... Based on these investigations, and FE analysis of other plate shell models, the structural behaviour is described. Possible methods of estimating the stresses in a given plate shell structure are proposed. The non-linear behaviour of a plate shell structure is investigated for varying parameters...

  3. Effects of the microbubble shell physicochemical properties on ultrasound-mediated drug delivery to the brain.

    Wu, Shih-Ying; Chen, Cherry C; Tung, Yao-Sheng; Olumolade, Oluyemi O; Konofagou, Elisa E


    Lipid-shelled microbubbles have been used in ultrasound-mediated drug delivery. The physicochemical properties of the microbubble shell could affect the delivery efficiency since they determine the microbubble mechanical properties, circulation persistence, and dissolution behavior during cavitation. Therefore, the aim of this study was to investigate the shell effects on drug delivery efficiency in the brain via blood-brain barrier (BBB) opening in vivo using monodisperse microbubbles with different phospholipid shell components. The physicochemical properties of the monolayer were varied by using phospholipids with different hydrophobic chain lengths (C16, C18, and C24). The dependence on the molecular size and acoustic energy (both pressure and pulse length) were investigated. Our results showed that a relatively small increase in the microbubble shell rigidity resulted in a significant increase in the delivery of 40-kDa dextran, especially at higher pressures. Smaller (3kDa) dextran did not show significant difference in the delivery amount, suggesting that the observed shell effect was molecular size-dependent. In studying the impact of acoustic energy on the shell effects, it was found that they occurred most significantly at pressures causing microbubble destruction (450kPa and 600kPa); by increasing the pulse length to deliver the 40-kDa dextran, the difference between C16 and C18 disappeared while C24 still achieved the highest delivery efficiency. These indicated that the acoustic energy could be used to modulate the shell effects. The acoustic cavitation emission revealed the physical mechanisms associated with different shells. Overall, lipid-shelled microbubbles with long hydrophobic chain length could achieve high delivery efficiency for larger molecules especially with high acoustic energy. Our study, for the first time, offered evidence directly linking the microbubble monolayer shell with their efficacy for drug delivery in vivo.

  4. Semiconducting, Magnetic or Superconducting Nanoparticles encapsulated in Carbon Shells by RAPET method.

    Aharon Gedanken


    Full Text Available An efficient, solvent-free, environmentally friendly, RAPET (Reactions under Autogenic Pressure at Elevated Temperaturesynthetic approach is discussed for the fabrication of core-shell nanostructures. The semiconducting, magnetic orsuperconducting nanoparticles are encapsulated in a carbon shell. RAPET is a one-step, thermal decomposition reaction ofchemical compound (s followed by the formation of core-shell nanoparticles in a closed stainless steel reactor. Therepresentative examples are discussed, where a variety of nanomaterials are trapped in situ in a carbon shell that offersfascinating properties.

  5. Composite shell spacecraft seat

    Barackman, Victor J. (Inventor); Pulley, John K. (Inventor); Simon, Xavier D. (Inventor); McKee, Sandra D. (Inventor)


    A two-part seat (10) providing full body support that is specific for each crew member (30) on an individual basis. The two-part construction for the seat (10) can accommodate many sizes and shapes for crewmembers (30) because it is reconfigurable and therefore reusable for subsequent flights. The first component of the two-part seat construction is a composite shell (12) that surrounds the crewmember's entire body and is generically fitted to their general size in height and weight. The second component of the two-part seat (10) is a cushion (20) that conforms exactly to the specific crewmember's entire body and gives total body support in more complex environment.

  6. Association between shell morphology of micro-land snails (genus Plectostoma and their predator’s predatory behaviour

    Thor-Seng Liew


    Full Text Available Predator–prey interactions are among the main ecological interactions that shape the diversity of biological form. In many cases, the evolution of the mollusc shell form is presumably driven by predation. However, the adaptive significance of several uncommon, yet striking, shell traits of land snails are still poorly known. These include the distorted coiled “tuba” and the protruded radial ribs that can be found in micro-landsnails of the genus Plectostoma. Here, we experimentally tested whether these shell traits may act as defensive adaptations against predators. We characterised and quantified the possible anti-predation behaviour and shell traits of Plectostoma snails both in terms of their properties and efficiencies in defending against the Atopos slug predatory strategies, namely, shell-apertural entry and shell-drilling. The results showed that Atopos slugs would first attack the snail by shell-apertural entry, and, should this fail, shift to the energetically more costly shell-drilling strategy. We found that the shell tuba of Plectostoma snails is an effective defensive trait against shell-apertural entry attack. None of the snail traits, such as resting behaviour, shell thickness, shell tuba shape, shell rib density and intensity can fully protect the snail from the slug’s shell-drilling attack. However, these traits could increase the predation costs to the slug. Further analysis on the shell traits revealed that the lack of effectiveness in these anti-predation shell traits may be caused by a functional trade-off between shell traits under selection of two different predatory strategies.

  7. Determination of the Optimal Shell Thickness for Self-Catalyzed GaAs/AlGaAs Core-Shell Nanowires on Silicon.

    Songmuang, R; Giang, Le Thuy Thanh; Bleuse, J; Den Hertog, M; Niquet, Y M; Dang, Le Si; Mariette, H


    We present a set of experimental results showing a combination of various effects, that is, surface recombination velocity, surface charge traps, strain, and structural defects, that govern the carrier dynamics of self-catalyzed GaAs/AlGaAs core-shell nanowires (NWs) grown on a Si(111) substrate by molecular beam epitaxy. Time-resolved photoluminescence of NW ensemble and spatially resolved cathodoluminescence of single NWs reveal that emission intensity, decay time, and carrier diffusion length of the GaAs NW core strongly depend on the AlGaAs shell thickness but in a nonmonotonic fashion. Although 7 nm AlGaAs shell can efficiently suppress the surface recombination velocity of the GaAs NW core, the influence of the surface charge traps and the strain between the core and the shell that redshift the luminescence of the GaAs NW core remain observable in the whole range of the shell thickness. In addition, the band bending effect induced by the surface charge traps can alter the scattering of the excess carriers inside the GaAs NW core at the core/shell interface. If the AlGaAs shell thickness is larger than 50 nm, the luminescence efficiency of the GaAs NW cores deteriorates, ascribed to defect formation inside the AlGaAs shell evidenced by transmission electron microscopy.

  8. Synthesis and characterization of ZnSe:Fe/ZnSe core/shell nanocrystals

    Yang, Lin; Zhu, Jianguo, E-mail:; Xiao, Dingquan


    High-quality ZnSe:Fe/ZnSe core/shell nanocrystals were prepared via a hydrothermal microemulsion technique. Effective surface passivation of monodisperse ZnSe:Fe nanocrystals is achieved by overcoating them with a ZnSe shell. The samples were characterized by means of XRD, EDX, TEM, PSD, XPS, photoluminescence, and Raman spectrum. The results show that the as-synthesized nanocrystals are cubic zinc blende ZnSe structure with high purity and the average particle size of ZnSe:Fe/ZnSe core/shell nanocrystal is larger than that of ZnSe:Fe core. The growth of ZnSe shell causes a small red shift in PL spectra, and then the PL quantum yield (QY) increases from 16% before shell growth to the maximum of 37% after increasing shell thickness up to 1.2 monolayers (ML). Moreover, both transverse optic (TO) and longitudinal optic (LO) phonon modes of ZnSe are shifted toward lower frequency as compared with the reported ones. -- Highlights: • ZnSe:Fe/ZnSe core/shell QDs were prepared by a hydrothermal microemulsion method. • ZnSe shell efficiently passivates surface defects by serving as a physical barrier. • The particle size and PL properties can be turned with the growth of ZnSe shell. • The luminescence efficiency and stability of QDs could be improved in this manner.

  9. Core-size-dependent catalytic properties of bimetallic Au/Ag core-shell nanoparticles.

    Haldar, Krishna Kanta; Kundu, Simanta; Patra, Amitava


    Bimetallic core-shell nanoparticles have recently emerged as a new class of functional materials because of their potential applications in catalysis, surface enhanced Raman scattering (SERS) substrate and photonics etc. Here, we have synthesized Au/Ag bimetallic core-shell nanoparticles with varying the core diameter. The red-shifting of the both plasmonic peaks of Ag and Au confirms the core-shell structure of the nanoparticles. Transmission electron microscopy (TEM) analysis, line scan EDS measurement and UV-vis study confirm the formation of core-shell nanoparticles. We have examined the catalytic activity of these core-shell nanostructures in the reaction between 4-nitrophenol (4-NP) and NaBH4 to form 4-aminophenol (4-AP) and the efficiency of the catalytic reaction is found to be increased with increasing the core size of Au/Ag core-shell nanocrystals. The catalytic efficiency varies from 41.8 to 96.5% with varying core size from 10 to 100 nm of Au/Ag core-shell nanoparticles, and the Au100/Ag bimetallic core-shell nanoparticle is found to be 12-fold more active than that of the pure Au nanoparticles with 100 nm diameter. Thus, the catalytic properties of the metal nanoparticles are significantly enhanced because of the Au/Ag core-shell structure, and the rate is dependent on the size of the core of the nanoparticles.

  10. Design of Gas-phase Synthesis of Core-Shell Particles by Computational Fluid - Aerosol Dynamics.

    Buesser, B; Pratsinis, S E


    Core-shell particles preserve the bulk properties (e.g. magnetic, optical) of the core while its surface is modified by a shell material. Continuous aerosol coating of core TiO2 nanoparticles with nanothin silicon dioxide shells by jet injection of hexamethyldisiloxane precursor vapor downstream of titania particle formation is elucidated by combining computational fluid and aerosol dynamics. The effect of inlet coating vapor concentration and mixing intensity on product shell thickness distribution is presented. Rapid mixing of the core aerosol with the shell precursor vapor facilitates efficient synthesis of hermetically coated core-shell nanoparticles. The predicted extent of hermetic coating shells is compared to the measured photocatalytic oxidation of isopropanol by such particles as hermetic SiO2 shells prevent the photocatalytic activity of titania. Finally the performance of a simpler, plug-flow coating model is assessed by comparisons to the present detailed CFD model in terms of coating efficiency and silica average shell thickness and texture.

  11. Study on modal characteristics of perforated shell using effective Young's modulus

    Jhung, Myung Jo, E-mail: [Korea Institute of Nuclear Safety, 19 Guseong-dong, Yuseong-gu, Daejeon 305-338 (Korea, Republic of); Yu, Seon Oh [Korea Institute of Nuclear Safety, 19 Guseong-dong, Yuseong-gu, Daejeon 305-338 (Korea, Republic of)


    Research highlights: > The effective Young's modulus of perforated shell is proposed for modal analysis. > The penetration pattern is almost negligible for effective elastic constants. > The frequency of perforated shell decreases significantly due to the hole effect. - Abstract: For the perforated cylindrical shell submerged in fluid, it is almost impossible to develop a finite element model due to the necessity of the fine meshing of the shell and the fluid at the same time. This necessitates the use of solid shell with effective material properties. Unfortunately the effective elastic constants are not found in any references even though the ASME code is suggesting those for perforated plate. Therefore in this study the effective material properties of perforated shell are suggested by performing several finite element analyses with respect to the ligament efficiencies.

  12. Synthesis and Near-infrared Luminescent Properties of NaGdF4:Nd3+@NaGdF4 Core/Shell Nanocrystals with Different Shell Thickness.

    Li, Xinke; You, Fangtian; Peng, Hongshang; Huang, Shihua


    The near-infrared to near-infrared (NIR-to-NIR) photoluminescence of nanocrystals has outstanding advantages in biological imaging. NaGdF4:Nd3+ core nanocrystals and NaGdF4:Nd3+@NaGdF4 core/shell nanocrystals with different shell thicknesses were synthesized by a simple solvothermal method. The obtained nanocrystals were characterized by transmission electron microscopy (TEM) and X-ray diffraction (XRD) analysis. The phase of all nanocrystals is hexagonal. NaGdF4:Nd3+ core nanocrystals have an average size of 6 nm. By controlling core-shell ratio for 1:2 and 1:3, we obtained NaGdF4:Nd3+@NaGdF4 core/shell nanocrystals with average sizes of 10 nm and 11 nm, respectively. When excited at 808 nm, strong NIR emission was observed. The emission peaks at -860 nm, -1060 nm and -1330 nm correspond to the transitions from the 4F3/2 state to the 4I9/2, 4I1/2 and 4I13/2 state of Nd3+ ions, respectively. The emission intensity of NaGdF4:Nd3+@NaGdF4 core/shell nanocrystals is stronger than that of the core. The intensity increases with the increase of shell thickness. The shell improves the luminous efficiency by reducing surface defects. The decay time of Nd3+ emission in NaGdF4:Nd3+@NaGdF4 core/shell nanocrystal is longer than that in NaGdF4:Nd3+ core, indicating that the shell isolates effectively the emitting ions (Nd3+) from the quenching defects. With the increase of shell thickness, the decay time becomes longer. Within a certain range of shell thickness, thicker shell can protect the emitting Nd3+ ions on the surface of core nanocrystals more effectively.

  13. Amphiphilic antioxidants from "cashew nut shell liquid" (CNSL) waste.

    Amorati, Riccardo; Attanasi, Orazio A; Favi, Gianfranco; Menichetti, Stefano; Pedulli, Gian Franco; Viglianisi, Caterina


    Hydrogenated cardanol and cardols, contained in industrial grade cardanol oil and obtained by distillation of the raw "cashew nut shell liquid" (CNSL), are easily transformed into efficient 4-thiaflavane antioxidants bearing a long alkyl chain on A ring and a catechol group on B ring.

  14. Biosorption of divalent Pb, Cd and Zn on aragonite and calcite mollusk shells

    Du Yang; Lian Fei [Key Laboratory of Pollution Process and Environmental Criteria, Ministry of Education, Tianjin Key Laboratory of Urban Ecology Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai University, Tianjin 300071 (China); Zhu Lingyan, E-mail: [Key Laboratory of Pollution Process and Environmental Criteria, Ministry of Education, Tianjin Key Laboratory of Urban Ecology Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai University, Tianjin 300071 (China)


    The potential of using mollusk shell powder in aragonite (razor clam shells, RCS) and calcite phase (oyster shells, OS) to remove Pb{sup 2+}, Cd{sup 2+} and Zn{sup 2+} from contaminated water was investigated. Both biogenic sorbents displayed very high sorption capacities for the three metals except for Cd on OS. XRD, SEM and XPS results demonstrated that surface precipitation leading to crystal growth took place during sorption. Calcite OS displayed a remarkably higher sorption capacity to Pb than aragonite RCS, while the opposite was observed for Cd. However, both sorbents displayed similar sorption capacities to Zn. These could be due to the different extent of matching in crystal lattice between the metal bearing precipitate and the substrates. The initial pH of the solution, sorbent's dosage and grain size affected the removal efficiency of the heavy meals significantly, while the organic matter in mollusk shells affected the removal efficiency to a lesser extent. - Highlights: > Mollusk shells display high removal efficiency to heavy metals in contaminated water. > Surface precipitation leading to crystal growth takes place during the sorption. > Crystal structure similarity between precipitates and substrates affects the sorption. > pH, sorbent dosage and grain size of adsorbent affects the removal efficiency. > Organic matter in mollusk shells affects the removal efficiency to a less extent. - Mollusk shells display high sorption ability to heavy metals and crystal structure similarity between precipitates and substrates affects the sorption.

  15. 基于Struts的Web应用安全问题研究%The Study of Security Issues in Struts-Based Web Applications

    彭剑; 朱小平


    对基于Struts框架的web应用的安全问题进行了分析和研究,通过扩展Servlet类和Struts Tag类建立了一种不影响系统性能、适应性广且能同时对web资源进行页面级和属性级安全控制的模型.在实现中,运用了Filter接口、TextTag类、web.xml配置文件和自定义的SecurityHelper接口.





  17. Evaluation of size effect on shear strength of reinforced concrete deep beams using refined strut-and-tie model

    G Appa Rao; R Sundaresan


    This paper reports on development of size-dependent shear strength expression for reinforced concrete deep beams using refined strut-and-tie model. The generic form of the size effect law has been retained considering the merits of Siao’s model and modified Bazant’s size effect law using the large experimental data base reported in the literature. The proposed equation for predicting the shear strength of deep beams incorporates the compressive strength of concrete, ratios of the longitudinal and the web reinforcement, shear span-to-depth ratio and the effective depth.

  18. A Common Web information System Integrated Design Based on Struts%基于Struts的通用Web信息系统集成设计

    张骏; 徐波丰



  19. MicroShell Minimalist Shell for Xilinx Microprocessors

    Werne, Thomas A.


    MicroShell is a lightweight shell environment for engineers and software developers working with embedded microprocessors in Xilinx FPGAs. (MicroShell has also been successfully ported to run on ARM Cortex-M1 microprocessors in Actel ProASIC3 FPGAs, but without project-integration support.) Micro Shell decreases the time spent performing initial tests of field-programmable gate array (FPGA) designs, simplifies running customizable one-time-only experiments, and provides a familiar-feeling command-line interface. The program comes with a collection of useful functions and enables the designer to add an unlimited number of custom commands, which are callable from the command-line. The commands are parameterizable (using the C-based command-line parameter idiom), so the designer can use one function to exercise hardware with different values. Also, since many hardware peripherals instantiated in FPGAs have reasonably simple register-mapped I/O interfaces, the engineer can edit and view hardware parameter settings at any time without stopping the processor. MicroShell comes with a set of support scripts that interface seamlessly with Xilinx's EDK tool. Adding an instance of MicroShell to a project is as simple as marking a check box in a library configuration dialog box and specifying a software project directory. The support scripts then examine the hardware design, build design-specific functions, conditionally include processor-specific functions, and complete the compilation process. For code-size constrained designs, most of the stock functionality can be excluded from the compiled library. When all of the configurable options are removed from the binary, MicroShell has an unoptimized memory footprint of about 4.8 kB and a size-optimized footprint of about 2.3 kB. Since MicroShell allows unfettered access to all processor-accessible memory locations, it is possible to perform live patching on a running system. This can be useful, for instance, if a bug is

  20. (Plasmonic Metal Core)/(Semiconductor Shell) Nanostructures

    Fang, Caihong

    Over the past several years, integration of metal nanocrystals that can support localized surface plasmon has been demonstrated as one of the most promising methods to the improvement of the light-harvesting efficiency of semiconductors. Ag and Au nanocrystals have been extensively hybridized with semiconductors by either deposition or anchoring. However, metal nanocrystals tend to aggregate, reshape, detach, or grow into large nanocrystals, leading to a loss of the unique properties seen in the original nanocrystals. Fortunately, core/shell nanostructures, circumventing the aforementioned problems, have been demonstrated to exhibit superior photoactivities. To further improve the light-harvesting applications of (plasmonic metal core)/(semiconductor shell) nanostructures, it is vital to understand the plasmonic and structural evolutions during the preparation processes, design novel hybrid nanostructures, and improve their light-harvesting performances. In this thesis, I therefore studied the plasmonic and structural evolutions during the formation of (Ag core)/(Ag2S shell) nanostructures. Moreover, I also prepared (noble metal core)/(TiO2 shell) nanostructures and investigated their plasmonic properties and photon-harvesting applications. Clear understanding of the sulfidation process can enable fine control of the plasmonic properties as well as the structural composition of Ag/Ag 2S nanomaterials. Therefore, I investigated the plasmonic and structural variations during the sulfidation process of Ag nanocubes both experimentally and numerically. The sulfidation reactions were carried out at both the ensemble and single-particle levels. Electrodynamic simulations were also employed to study the variations of the plasmonic properties and plasmon modes. Both experiment and simulation results revealed that sulfidation initiates at the vertices of Ag nanocubes. Ag nanocubes are then gradually truncated and each nanocube becomes a nanosphere eventually. The cubic

  1. Efficient morphological reconstruction: a downhill filter

    Robinson, Kevin; Whelan, Paul F.


    The Downhill filter is an elegant and efficient single pass reconstruction algorithm which demonstrates fast and consistent performance. It operates through a controlled process of region growing by ordered aggregation of surface pixels onto an expanding shell


    Degtyarev G. V.


    Full Text Available The method of estimation of bearing strength of braces and struts of farms of coverage of hothouses is presented in the article. The deep analysis of the question of bearing strength appeared in the light of mass erection of hothouses, especially in the South Federal district, the construction of which had been bought in the countries of Near East. However, simple transfer of the constructions of hothouses made in foreign countries can not be considered as rational on the territory of the Russian Federation. The constructions of hothouses in most do not maintain exploitation even in one winter, when the considerable snow loadings are, and wind as well. The necessity of bringing of clarity for the folded situation became more obvious. Conducted successive static, dynamic and seismic analyses, executed upon the normative documents and due to the norms of supplier operating on the territory of the Russian Federation, in attachment to the real sections of bearings structural elements, allowed to expose the stated below percents of the use of the examined elements of constructions. Supporting braces of farms of coverage: on the norms of the Russian Federation, on the first maximum state percent of the use – 999 %; there is a percent of the use on the second maximum state – 999 %; on the norms of the Russian Federation taking into account loadings of supplier, on the first maximum state percent of the use – 999 %; there is a percent of the use on the second maximum state – 999 %; Stretched braces of farms of coverage: on the norms of the Russian Federation, on the first maximum state percent of the use – 64,2%; there is a percent of the use on the second maximum state – 721,8 %; on the norms of the Russian Federation taking into account loadings of supplier, on the first maximum state percent of the use – 25,8 %; there is a percent of the use on the second maximum state – 721,8%. Analysis presented allows establishing that at the load

  3. Ion Structure Near a Core-Shell Dielectric Nanoparticle

    Ma, Manman; Gan, Zecheng; Xu, Zhenli


    A generalized image charge formulation is proposed for the Green's function of a core-shell dielectric nanoparticle for which theoretical and simulation investigations are rarely reported due to the difficulty of resolving the dielectric heterogeneity. Based on the formulation, an efficient and accurate algorithm is developed for calculating electrostatic polarization charges of mobile ions, allowing us to study related physical systems using the Monte Carlo algorithm. The computer simulations show that a fine-tuning of the shell thickness or the ion-interface correlation strength can greatly alter electric double-layer structures and capacitances, owing to the complicated interplay between dielectric boundary effects and ion-interface correlations.

  4. Core–shell quantum dots: Properties and applications

    Vasudevan, D., E-mail: [Electrodics and electrocatalysis division, CSIR-CECRI, Karaikudi 630006 (India); Gaddam, Rohit Ranganathan [Amity Institute of Nanotechnology, Amity University, Noida 201301 (India); Trinchi, Adrian; Cole, Ivan [CSIRO Materials Science and Engineering, Clayton South MDC, 3169 (Australia)


    Fluorescent quantum dots (QDs) are semiconducting nanocrystals (NCs) that find numerous applications in areas, such as bio labelling, sensors, lasers, light emitting diodes and medicine. Core–shell quantum dots were developed to improve the photoluminescence efficiency of single quantum dots. Capping their surface with organic ligands as well as their extraction into aqueous media enables their use in sensing applications. The current review highlights the importance and applications of core shell quantum dots as well as their surface modifications and applications in the field of medicine and as sensors for chemical and biochemical analysis.

  5. Pro Windows PowerShell

    Deshev, Hristo


    Targeted at professionals who handle a lot of repetitive tasks, this title serves as not only a tutorial, but also a reference. It shows how PowerShell can help professionals script most system administration tasks and reduce their burden.

  6. Instant Windows PowerShell

    Menon, Vinith


    Get to grips with a new technology, understand what it is and what it can do for you, and then get to work with the most important features and tasks. A practical, hands-on tutorial approach that explores the concepts of PowerShell in a friendly manner, taking an adhoc approach to each topic.If you are an administrator who is new to PowerShell or are looking to get a good grounding in these new features, this book is ideal for you. It's assumed that you will have some experience in PowerShell and Windows Server, as well being familiar with the PowerShell command-line.

  7. Patterning of the turtle shell.

    Moustakas-Verho, Jacqueline E; Cebra-Thomas, Judith; Gilbert, Scott F


    Interest in the origin and evolution of the turtle shell has resulted in a most unlikely clade becoming an important research group for investigating morphological diversity in developmental biology. Many turtles generate a two-component shell that nearly surrounds the body in a bony exoskeleton. The ectoderm covering the shell produces epidermal scutes that form a phylogenetically stable pattern. In some lineages, the bones of the shell and their ectodermal covering become reduced or lost, and this is generally associated with different ecological habits. The similarity and diversity of turtles allows research into how changes in development create evolutionary novelty, interacting modules, and adaptive physiology and anatomy. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Rotating thin-shell wormhole

    Ovgun, A.


    We construct a rotating thin-shell wormhole using a Myers-Perry black hole in five dimensions, using the Darmois-Israel junction conditions. The stability of the wormhole is analyzed under perturbations. We find that exotic matter is required at the throat of the wormhole to keep it stable. Our analysis shows that stability of the rotating thin-shell wormhole is possible if suitable parameter values are chosen.

  9. 40 Years of Shell Scenarios



    Shell has been using scenario planning for four decades. During that time these scenarios have helped the company and governments across the world to make better strategic choices. Scenarios provide lenses that help see future prospects more clearly, make richer judgments and be more sensitive to uncertainties. Discover how the Shell Scenarios team has helped guide decision makers at major moments in history and get a peek at the team future focus, including the intricate relationship between energy, water and food.

  10. Rotating Thin-Shell Wormhole

    Ovgun, A


    In this article, we construct rotating thin shell wormhole using a Myers-Perry black hole in five dimensions. The stability of the wormhole is analyzed under perturbations follows from the Darmois-Israel junction conditions. We find that it required exotic matter at the throat to keep throat of wormhole stable. Our analysis shows that the stability of the rotating thin-shell wormhole is available with choosing suitable values of parameters.

  11. Stellar Populations of Shell Galaxies

    Carlsten, S; Zenteno, A


    We present a study of the inner (out to $\\sim$1 R$_{\\mathrm{eff}}$) stellar populations of 9 shell galaxies. We derive stellar population parameters from long slit spectra by both analyzing the Lick indices of the galaxies and by fitting Single Stellar Population model spectra to the full galaxy spectra. The results from the two methods agree reasonably well. Many of the shell galaxies in our sample appear to have lower central $\\mathrm{Mg}_{2}$ index values than non-shell galaxies of the same central velocity dispersion, which is likely due to a past interaction event. Our shell galaxy sample shows a relation between central metallicity and velocity dispersion that is consistent with previous samples of non-shell galaxies. Analyzing the metallicity gradients in our sample, we find an average metallicity gradient of -0.16$\\pm$0.10 dex per decade in radius. We compare this with formation models to constrain the merging history of shell galaxies. We argue that our galaxies likely have undergone major mergers in...

  12. Hiper Strut新型悬架对整车操纵稳定性的影响评价%Influence of Hiper Strut Suspension on Vehicle Handling Stability

    孙明浩; 侯志国; 桂军


    为研究Hiper Strut(High Performance Strut)新型悬架对整车操纵稳定性的影响,将一款国产SUV所使用的麦弗逊前悬架替换为适用于该车的Hiper Strut前悬架.利用Adams/Car建立使用Hiper Strut前悬架的整车仿真模型,并进行相关操纵稳定性仿真试验.仿真结果表明,使用该新型悬架的整车在操纵稳定性评价中得分较高,说明Hiper Strut悬架的结构设计有助于提高整车操纵稳定性.所建模型及仿真分析对Hiper Strut新型悬架的深入研究和推广应用具有一定的实际参考价值.

  13. Axial stent strut angle influences wall shear stress after stent implantation: analysis using 3D computational fluid dynamics models of stent foreshortening

    Warltier David C


    Full Text Available Abstract Introduction The success of vascular stents in the restoration of blood flow is limited by restenosis. Recent data generated from computational fluid dynamics (CFD models suggest that the vascular geometry created by an implanted stent causes local alterations in wall shear stress (WSS that are associated with neointimal hyperplasia (NH. Foreshortening is a potential limitation of stent design that may affect stent performance and the rate of restenosis. The angle created between axially aligned stent struts and the principal direction of blood flow varies with the degree to which the stent foreshortens after implantation. Methods In the current investigation, we tested the hypothesis that stent foreshortening adversely influences the distribution of WSS and WSS gradients using time-dependent 3D CFD simulations of normal arteries based on canine coronary artery measurements of diameter and blood flow. WSS and WSS gradients were calculated using conventional techniques in ideal (16 mm and progressively foreshortened (14 and 12 mm stented computational vessels. Results Stent foreshortening increased the intrastrut area of the luminal surface exposed to low WSS and elevated spatial WSS gradients. Progressive degrees of stent foreshortening were also associated with strut misalignment relative to the direction of blood flow as indicated by analysis of near-wall velocity vectors. Conclusion The current results suggest that foreshortening may predispose the stented vessel to a higher risk of neointimal hyperplasia.

  14. Isogeometric shell formulation based on a classical shell model

    Niemi, Antti


    This paper constitutes the first steps in our work concerning isogeometric shell analysis. An isogeometric shell model of the Reissner-Mindlin type is introduced and a study of its accuracy in the classical pinched cylinder benchmark problem presented. In contrast to earlier works [1,2,3,4], the formulation is based on a shell model where the displacement, strain and stress fields are defined in terms of a curvilinear coordinate system arising from the NURBS description of the shell middle surface. The isogeometric shell formulation is implemented using the PetIGA and igakit software packages developed by the authors. The igakit package is a Python package used to generate NURBS representations of geometries that can be utilised by the PetIGA finite element framework. The latter utilises data structures and routines of the portable, extensible toolkit for scientific computation (PETSc), [5,6]. The current shell implementation is valid for static, linear problems only, but the software package is well suited for future extensions to geometrically and materially nonlinear regime as well as to dynamic problems. The accuracy of the approach in the pinched cylinder benchmark problem and present comparisons against the h-version of the finite element method with bilinear elements. Quadratic, cubic and quartic NURBS discretizations are compared against the isoparametric bilinear discretization introduced in [7]. The results show that the quadratic and cubic NURBS approximations exhibit notably slower convergence under uniform mesh refinement as the thickness decreases but the quartic approximation converges relatively quickly within the standard variational framework. The authors future work is concerned with building an isogeometric finite element method for modelling nonlinear structural response of thin-walled shells undergoing large rigid-body motions. The aim is to use the model in a aeroelastic framework for the simulation of flapping wings.

  15. Strutting Her Stuff


    Hip-hop granny rolls back the years to prove that with passion,anything is possible Who says hip hop belongs to the teenagers? In China,more and more seniors are choosing this trendy dance style as a way to keep fit,rather than the more serene move- ments of taiji or ballroom dancing in the parks. Wu Ying is one of them.The 71-year- old Wu is the founder of a granny hip-hop dance team in Beijing,whose participants are in their 60s.Wu is the oldest in the team.In their loose modern outfits and hair wrapped in bandanas,these old ladies are

  16. Cocoa shells for heavy metal removal from acidic solutions.

    Meunier, N; Laroulandie, J; Blais, J F; Tyagi, R D


    The development of economic and efficient processes for the removal of heavy metals present in acidic effluents from industrial sources or decontamination technologies has become a priority. The purpose of this work was to study the efficiency with which cocoa shells remove heavy metals from acidic solutions (pH 2) and to investigate how the composition of these solutions influences heavy metal uptake efficiency. Adsorption tests were conducted in agitated flasks with single-metal solutions (0.25 mM Al, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb and Zn), multi-metal solution (comprised of 0.25 mM of each of the cations above) and an effluent obtained from chemical leaching of metal-contaminated soil, in the presence of different cocoa shell concentrations (5-40 g/l). Results from the single-metal solution assays indicated that the fixation capacity of heavy metals by cocoa shells followed a specific order: Pb>Cr>Cd=Cu=Fe>Zn=Co>Mn=Ni=Al. Cocoa shells are particularly efficient in the removal of lead from very acidic solutions (q(max)=6.2 mg Pb/g, pH(i)=2.0 and T=22 degrees C). The presence of other metals and cations in solution did not seem to affect the recovery of lead. It was also observed that the maximum metal uptake was reached in less than 2 h. This research has also demonstrated that the removal of metals caused a decline in solution proton concentration (pH increase) and release of calcium, magnesium, potassium and sodium from the cocoa shells.

  17. Controllable core-shell-type resin for solid-phase peptide synthesis.

    Cho, Hong-Jun; Lee, Tae-Kyung; Kim, Jung Won; Lee, Sang-Myung; Lee, Yoon-Sik


    A simple, mild, and inexpensive biphasic functionalization approach is attempted for preparing an ideal core-shell-type resin. The core-shell-type architecture was constructed by coupling Fmoc-OSu to the amino groups on the shell layer of an aminomethyl polystyrene (AM PS) resin. The shell layer thickness of the resin could be easily controlled under mild conditions, which was characterized by confocal laser scanning microscopy (CLSM). The efficiency of core-shell-type resin for solid-phase peptide synthesis (SPPS) was demonstrated by the synthesis of various peptides and compared with commercially available noncore-shell-type resins such as AM PS and poly(ethylene glycol)-based resins. The core-shell-type resin provided effective performance during the synthesis of hydrophobic peptide sequences, a disulfide-bridged cyclic peptide, and a difficult PNA sequence. Furthermore, a highly aggregative peptide fragment, MoPrP 105-125, was synthesized more efficiently on the core-shell-type resin under microwave conditions than AM PS and ChemMatrix resins.

  18. Rapid and Efficient One-Pot Synthesis of 3,4-Dihydroquinoxalin-2-Amine Derivatives Catalyzed by Co3O4@SiO2 Core-Shell Nanoparticles Under Ultrasound Irradiation.

    Ghasemzadeh, Mohammad Ali; Mirhosseini-Eshkevari, Boshra; Abdollahi-Basir, Mohammad Hossein


    In this research, a general synthetic method for the synthesis of 3,4- dihydroquinoxalin-2-amine derivatives was developed using Co3O4@SiO2 nanoparticles under ultrasonic irradiation. Firstly by a simple and green process, Co3O4;@SiO2 nanoparticles were prepared via sonication, and then these nanoparticles were used as an efficient catalyst for the synthesis of 3,4- dihydroquinoxalin-2-amines via three-component reactions of ophenylenediamines (OPDA), diverse ketones and various isocyanides in ethanol under ultrasound irradiation. The combinatorial synthesis was attained for this procedure with applying ultrasound irradiation while making use of ethanol as green ambient. The present approach offers several advantages such as high yields, environmentally benign, simple work-up, excellent yield of products and short reaction times. The nanomagnetic catalyst could be readily recovered using a simple external magnet and reused several times without any significant loss in activity. The catalyst was fully characterized by FT-IR, FE-SEM, XRD, EDX, VSM and TEM analysis.



    Under certain conditions, the dynamic equatioins of membrane shells and the dynamic equations of flexural shells are obtained from dynamic equations of Koiter shells by the method of asymptotic analysis.

  20. Critical velocity of sandwich cylindrical shell under moving internal pressure


    Critical velocity of an infinite long sandwich shell under moving internal pres-sure is studied using the sandwich shell theory and elastodynamics theory. Propagation of axisymmetric free harmonic waves in the sandwich shell is studied using the sandwich shell theory by considering compressibility and transverse shear deformation of the core, and transverse shear deformation of face sheets. Based on the elastodynamics theory, displacement components expanded by Legendre polynomials, and position-dependent elastic constants and densities are introduced into the equations of motion. Critical ve-locity is the minimum phase velocity on the desperation relation curve obtained by using the two methods. Numerical examples and the finite element (FE) simulations are pre-sented. The results show that the two critical velocities agree well with each other, and two desperation relation curves agree well with each other when the wave number κ is relatively small. However, two limit phase velocities approach to the shear wave velocities of the face sheet and the core respectively when k limits to infinite. The two methods are efficient in the investigation of wave propagation in a sandwich cylindrical shell when κ is relatively small. The critical velocity predicted in the FE simulations agrees with theoretical prediction.

  1. Experimental Damage Identification of a Model Reticulated Shell

    Jing Xu


    Full Text Available The damage identification of a reticulated shell is a challenging task, facing various difficulties, such as the large number of degrees of freedom (DOFs, the phenomenon of modal localization and transition, and low modeling accuracy. Based on structural vibration responses, the damage identification of a reticulated shell was studied. At first, the auto-regressive (AR time series model was established based on the acceleration responses of the reticulated shell. According to the changes in the coefficients of the AR model between the damaged conditions and the undamaged condition, the damage of the reticulated shell can be detected. In addition, the damage sensitive factors were determined based on the coefficients of the AR model. With the damage sensitive factors as the inputs and the damage positions as the outputs, back-propagation neural networks (BPNNs were then established and were trained using the Levenberg–Marquardt algorithm (L–M algorithm. The locations of the damages can be predicted by the back-propagation neural networks. At last, according to the experimental scheme of single-point excitation and multi-point responses, the impact experiments on a K6 shell model with a scale of 1/10 were conducted. The experimental results verified the efficiency of the proposed damage identification method based on the AR time series model and back-propagation neural networks. The proposed damage identification method can ensure the safety of the practical engineering to some extent.

  2. Stress and vibraton analyses of anisotropic shells of revolution

    Noor, Ahmed K.; Peters, Jeanne M.


    An efficient computational strategy is presented for reducing the cost of the stress and free vibration analyses of laminated anisotropic shells of revolution. The analytical formulation is based on a form of the Sanders-Budiansky shell theory including the effects of both the transverse shear deformation and the laminated anisotropic material response. The fundamental unknowns consist of the eight strain components, the eight stress resultants and the five generalized displacements of the shell. Each of the shell variables is expressed in terms of trigonometric functions (Fourier series) in the circumferential co-ordinate, and a three-field mixed finite element model is used for the discretization in the meridional direction. The shell response associated with a range of Fourier harmonics is approximated by a linear combination of a few global approximation vectors, which are generated at a particular value of the Fourier harmonic, within that range. The full equations of the finite element model are solved for only a single Fourier harmonic, and the response corresponding to the other Fourier harmonics is generated using a reduced system of equations with considerably fewer degrees of freedom.

  3. Magnetic nanohybrids loaded with bimetal core-shell-shell nanorods for bacteria capture, separation, and near-infrared photothermal treatment.

    Hu, Bo; Wang, Ning; Han, Lu; Chen, Ming-Li; Wang, Jian-Hua


    A novel antimicrobial nanohybrid based on near-infrared (NIR) photothermal conversion is designed for bacteria capture, separation, and sterilization (killing). Positively charged magnetic reduced graphene oxide with modification by polyethylenimine (rGO-Fe3 O4 -PEI) is prepared and then loaded with core-shell-shell Au-Ag-Au nanorods to construct the nanohybrid rGO-Fe3 O4 -Au-Ag-Au. NIR laser irradiation melts the outer Au shell and exposes the inner Ag shell, which facilitates controlled release of the silver shell. The nanohybrids combine physical photothermal sterilization as a result of the outer Au shell with the antibacterial effect of the inner Ag shell. In addition, the nanohybrid exhibits high heat conductivity because of the rGO and rapid magnetic-separation capability that is attributable to Fe3 O4 . The nanohybrid provides a significant improvement of bactericidal efficiency with respect to bare Au-Ag-Au nanorods and facilitates the isolation of bacteria from sample matrixes. A concentration of 25 μg mL(-1) of nanohybrid causes 100 % capture and separation of Escherichia coli O157:H7 (1×10(8) cfu mL(-1) ) from an aqueous medium in 10 min. In addition, it causes a 22 °C temperature rise for the surrounding solution under NIR irradiation (785 nm, 50 mW cm(-2) ) for 10 min. With magnetic separation, 30 μg mL(-1) of nanohybrid results in a 100 % killing rate for E. coli O157:H7 cells. The facile bacteria separation and photothermal sterilization is potentially feasible for environmental and/or clinical treatment.

  4. The Ag shell thickness effect of Au@Ag@SiO2 core-shell nanoparticles on the optoelectronic performance of dye sensitized solar cells.

    Wang, Yang; Zhai, Jin; Song, Yanlin; He, Ling


    To tailor the Au@Ag@SiO2 LSPR effect by varying the Ag shell thickness, the Au@Ag@SiO2 core-ultra-thin shell nanoparticles are fabricated and introduced into DSSC for improving light harvesting and decreasing the recombination of photo-carriers. The Au@Ag@SiO2 electrode exhibits a photo-conversion efficiency of 23.42% (486.7 nm, 10 mW cm(-2)).

  5. Compare ultrasound-mediated heating and cavitation between flowing polymer- and lipid-shelled microbubbles during focused ultrasound exposures.

    Zhang, Siyuan; Zong, Yujin; Wan, Mingxi; Yu, Xiaojun; Fu, Quanyou; Ding, Ting; Zhou, Fanyu; Wang, Supin


    This paper compares the efficiency of flowing polymer- and lipid-shelled microbubbles (MBs) in the heating and cavitation during focused ultrasound exposures. Temperature and cavitation activity were simultaneously measured as the two types of shelled MBs and saline flowing through a 3 mm diameter vessel in the phantom with varying flow velocities (0-20 cm/s) at different acoustic power levels (0.6-20 W) with each exposure for 5 s. Temperature and cavitation for the lipid-shelled MBs were higher than those for the polymer-shelled MBs. Temperature rise decreased with increasing flow velocities for the two types of shelled MBs and saline at acoustic power 1.5 W. At acoustic power 11.1 W, temperature rise increased with increasing flow velocities for the lipid-shelled MBs. For the polymer-shelled MBs, the temperature rise increased with increasing flow velocities from 3-15 cm/s and decreased at 20 cm/s. Cavitation increased with increasing flow velocity for the two shelled MBs and there were no significant changes of cavitation with increasing flow velocities for saline. These results suggested that lipid-shelled MBs may have a greater efficiency than polymer-shelled MBs in heating and cavitation during focused ultrasound exposures.

  6. Dependences of optical properties of spherical two-layered nanoparticles on parameters of gold core and material shell

    Pustovalov, V. K.; Astafyeva, L. G.; Zharov, V. P.


    Modeling of nonlinear dependences of optical properties of spherical two-layered gold core and some material shell nanoparticles (NPs) placed in water on parameters of core and shell was carried out on the basis of the extended Mie theory. Efficiency cross-sections of absorption, scattering and extinction of radiation with wavelength 532 nm by core-shell NPs in the ranges of core radii r00=5-40 nm and of relative NP radii r1/r00=1-8 were calculated (r1-radius of two-layered nanoparticle). Shell materials were used with optical indexes in the ranges of refraction n1=0.2-1.5 and absorption k1=0-3.5 for the presentation of optical properties of wide classes of shell materials (including dielectrics, metals, polymers, vapor shell around gold core). Results show nonlinear dependences of optical properties of two-layered NPs on optical indexes of shell material, core r00 and relative NP r1/r00 radii. Regions with sharp decrease and increase of absorption, scattering and extinction efficiency cross-sections with changing of core and shell parameters were investigated. These dependences should be taken into account for applications of two-layered NPs in laser nanomedicine and optical diagnostics of tissues. The results can be used for experimental investigation of shell formation on NP core and optical determination of geometrical parameters of core and shell of two-layered NPs.

  7. Black hole entropy off-shell vs on-shell

    Frolov, V P; Zelnikov, A I


    Different methods of calculation of quantum corrections to the thermodynamical characteristics of a black hole are discussed and compared. The relation between on-shell and off-shell approaches is established. The off-shell methods are used to explicitly demonstrate that the thermodynamical entropy S^{TD} of a black hole, defined by the first thermodynamical law, differs from the statistical-mechanical entropy S^{SM}, determined as S^{SM}=-\\mbox{Tr}(\\hat{\\rho}^H\\ln\\hat{\\rho}^H) for the density matrix \\hat{\\rho}^H of a black hole. It is shown that the observable thermodynamical black hole entropy can be presented in the form S^{TD}=\\pi {\\bar r}_+^2+S^{SM}-S^{SM}_{Rindler}. Here {\\bar r}_+ is the radius of the horizon shifted because of the quantum backreaction effect, and S^{SM}_{Rindler} is the statistical-mechanical entropy calculated in the Rindler space.

  8. Studies on Thin-shells and Thin-shell Wormholes

    Övgün, Ali


    The study of traversable wormholes is very hot topic for the past 30 years. One of the best possible way to make traversable wormhole is using the thin-shells to cut and paste two spacetime which has tunnel from one region of space-time to another, through which a traveler might freely pass in wormhole throat. These geometries need an exotic matter which involves a stress-energy tensor that violates the null energy condition. However, this method can be used to minimize the amount of the exotic matter. The goal of this thesis study is to study on thin-shell and thin-shell wormholes in general relativity in 2+1 and 3+1 dimensions. We also investigate the stability of such objects.

  9. Design and optimization of Ag-dielectric core-shell nanostructures for silicon solar cells

    Feng-Xiang Chen


    Full Text Available Metal-dielectric core-shell nanostructures have been proposed as a light trapping scheme for enhancing the optical absorption of silicon solar cells. As a potential application of such enhanced effects, the scattering efficiencies of three core-shell structures (Ag@SiO2, Ag@TiO2, and Ag@ZrO2 are discussed using the Mie Scattering theory. For compatibility with experiment results, the core diameter and shell thickness are limited to 100 and 30 nm, respectively, and a weighted scattering efficiency is introduced to evaluate the scattering abilities of different nanoparticles under the solar spectrum AM 1.5. The simulated results indicate that the shell material and thickness are two key parameters affecting the weighted scattering efficiency. The SiO2 is found to be an unsuitable shell medium because of its low refractive index. However, using the high refractive index mediumTiO2 in Ag@TiO2 nanoparticles, only the thicker shell (30 nm is more beneficial for light scattering. The ZrO2 is an intermediate refractive index material, so Ag@ZrO2 nanoparticles are the most effective core-shell nanostructures in these silicon solar cells applications.

  10. Multiple Criteria Decision Making: Efficient Outcome Assessments with Evolutionary Optimization

    Kaliszewski, Ignacy; Miroforidis, Janusz

    We propose to derive assessments of outcomes to MCDM problems instead of just outcomes and carry decision making processes with the former. In contrast to earlier works in that direction, which to calculate assessments make use of subsets of the efficient set (shells), here we provide formulas for calculation of assessments based on the use of upper and lower approximations (upper and lower shells) of the efficient set, derived by evolutionary optimization. Hence, by replacing shells, which are to be in general derived by optimization, by pairs of upper and lower shells, exact optimization methods can be eliminated from MCDM.

  11. Shell-model calculations for p-shell hypernuclei

    Millener, D. J.


    The interpretation of hypernuclear gamma-ray data for p-shell hypernuclei in terms of shell-model calculations that include the coupling of Lambda- and Sigma-hypernuclear states is briefly reviewed. Next, Lambda 8Li, Lambda 8Be, and Lambda 9Li are considered, both to exhibit features of Lambda-Sigma coupling and as possible source of observed, but unassigned, hypernuclear gamma rays. Then, the feasibility of measuring the ground-state doublet spacing of Lambda 10Be, which, like Lambda 9Li, co...

  12. Windows PowerShell 20 Bible

    Lee, Thomas; Schill, Mark E; Tanasovski, Tome


    Here's the complete guide to Windows PowerShell 2.0 for administrators and developers Windows PowerShell is Microsoft's next-generation scripting and automation language. This comprehensive volume provides the background that IT administrators and developers need in order to start using PowerShell automation in exciting new ways. It explains what PowerShell is, how to use the language, and specific ways to apply PowerShell in various technologies. Windows PowerShell is Microsoft's standard automation tool and something that every Windows administrator will eventually have to understand; this b

  13. Shell Models of Magnetohydrodynamic Turbulence

    Plunian, Franck; Frick, Peter


    Shell models of hydrodynamic turbulence originated in the seventies. Their main aim was to describe the statistics of homogeneous and isotropic turbulence in spectral space, using a simple set of ordinary differential equations. In the eighties, shell models of magnetohydrodynamic (MHD) turbulence emerged based on the same principles as their hydrodynamic counter-part but also incorporating interactions between magnetic and velocity fields. In recent years, significant improvements have been made such as the inclusion of non-local interactions and appropriate definitions for helicities. Though shell models cannot account for the spatial complexity of MHD turbulence, their dynamics are not over simplified and do reflect those of real MHD turbulence including intermittency or chaotic reversals of large-scale modes. Furthermore, these models use realistic values for dimensionless parameters (high kinetic and magnetic Reynolds numbers, low or high magnetic Prandtl number) allowing extended inertial range and accu...

  14. AI-Based Diagnostic Shell

    R. L. Verma


    Full Text Available This paper datails the design and implementation of an AI-based diagnostic shell. The shell has a user-interface which takes in the complaint and aids the user throughout the consultation. The 'expert knowledge' is acquired and encoded in the form of 'IF-THEN' rules, The control mechanism routes through the rules chaining first backwards to identify a fault and then forwards to confirm it.Explanation facilities have been provided to enable the user query the reason for any question asked, a facility to go back and re-answer any previous question, and a trace and explanation of the path of reasoning.This shell was developed and first used for the diagnosis of a digital exchange. It was then applied for the fault-finding of the moving target indicator used in the radar.

  15. Asymptotic safety goes on shell

    Benedetti, Dario


    It is well known in quantum field theory that the off-shell effective action depends on the gauge choice and field parametrization used in calculating it. Nevertheless, the typical scheme in which the scenario of asymptotically safe gravity is investigated is an off-shell version of the functional renormalization group equation. Working with the Einstein-Hilbert truncation as a test bed, we develop a new scheme for the analysis of asymptotically safe gravity in which the on-shell part of the effective action is singled out and we show that the beta function for the essential coupling has no explicit gauge dependence. In order to reach our goal, we introduce several technical novelties, including a different decomposition of the metric fluctuations, a new implementation of the ghost sector and a new cut-off scheme. We find a nontrivial fixed point, with a value of the cosmological constant that is independent of the gauge-fixing parameters.

  16. Clinical and angiographic outcomes following first-in-man implantation of a novel thin-strut low-profile fixed-wire stent: The Svelte Coronary Stent Integrated Delivery System first-in-man trial

    R. Diletti (Roberto); H.M. Garcia-Garcia (Hector); C.V. Bourantas (Christos); R.J.M. van Geuns (Robert Jan); N.M. van Mieghem (Nicolas); P. Agostoni (Pierfrancesco); T. Muramatsu (Takashi); V. Farooq (Vasim); R. Spencer (Richard); J. de Schepper; M. Pomeranz (Mark); P.R. Stella (Pieter); P.W.J.C. Serruys (Patrick)


    textabstractAims: The Svelte Stent Integrated Delivery System (IDS) is a novel fixed-wire thin-strut cobalt-chromium stent characterised by a very low entry profile. The aim of the present study is to evaluate the safety and the feasibility of the Svelte stent IDS implantation in humans. Methods and

  17. Coordination polymer core/shell structures: Preparation and up/down-conversion luminescence.

    Li, Bingmei; Xu, Hualan; Xiao, Chen; Shuai, Min; Chen, Weimin; Zhong, Shengliang


    Coordination polymer (CP) core-shell nanoparticles with Gd-based CP (GdCP) as core and Eu-based CP (EuCP) as shell have been successfully prepared. Allantoin was employed as the organic building block without the assistance of any template. The composition, size and structure of the core-shell nanospheres were well characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive X-ray (EDX), powder X-ray diffraction (PXRD), Fourier transform infrared spectroscopy (FT-IR), thermo-gravimetric analysis (TG). Results show that the resultant cores are uniform nanospheres with diameter of approximately 45nm, while the diameters of the core-shell nanospheres are increased to approximately 60nm. The core-shell products show enhanced luminescence efficiency than the core under 980nm laser excitation and decreased down-conversion luminescence when excited at 394nm.

  18. Thermosensitive Cu2O-PNIPAM core-shell nanoreactors with tunable photocatalytic activity

    Jia, He; Angioletti-Uberti, Stefano; Henzler, Katja; Ott, Andreas; Lin, Xianzhong; Möser, Jannik; Kochovski, Zdravko; Schnegg, Alexander; Dzubiella, Joachim; Ballauff, Matthias; Lu, Yan


    We report a facile and novel method for the fabrication of Cu2O@PNIPAM core-shell nanoreactors using Cu2O nanocubes as the core. The PNIPAM shell not only effectively protects the Cu2O nanocubes from oxidation, but also improves the colloidal stability of the system. The Cu2O@PNIPAM core-shell microgels can work efficiently as photocatalyst for the decomposition of methyl orange under visible light. A significant enhancement in the catalytic activity has been observed for the core-shell microgels compared with the pure Cu2O nanocubes. Most importantly, the photocatalytic activity of the Cu2O nanocubes can be further tuned by the thermosensitive PNIPAM shell, as rationalized by our recent theory.

  19. Preparation and characterization of antibacterial Au/C core-shell composite

    Gao Yanhong [Department of Chemistry and Institute of Nanochemistry, Jinan University, 601 Huangpudadaoxi Road, Guangzhou 510632, Guangdong (China); Centers for Disease Control and Prevention of Guangdong Province, Guangzhou 510300, Guangdong (China); Zhang Nianchun [Department of Chemistry and Institute of Nanochemistry, Jinan University, 601 Huangpudadaoxi Road, Guangzhou 510632, Guangdong (China); Zhong Yuwen [Centers for Disease Control and Prevention of Guangdong Province, Guangzhou 510300, Guangdong (China); Cai Huaihong [Department of Chemistry and Institute of Nanochemistry, Jinan University, 601 Huangpudadaoxi Road, Guangzhou 510632, Guangdong (China); Liu Yingliang, E-mail: [Department of Chemistry and Institute of Nanochemistry, Jinan University, 601 Huangpudadaoxi Road, Guangzhou 510632, Guangdong (China)


    An environment-friendly oxidation-reduction method was used to prepare Au/C core-shell composite using carbon as core and gold as shell. The chemical structures and morphologies of Au/C core-shell composite and carbon sphere were characterized by X-ray diffraction, transmission electron microscope, energy dispersion X-ray spectrometry (EDS) and X-ray photoelectron spectroscopy (XPS). The antibacterial properties of the Au/C core-shell composite against Escherichia coli (E. coli), Staphylococcus aureus (S. aureus) and Candida albicans (C. albicans) were examined by the disk diffusion assay and minimal inhibition concentration (MIC) methods. In addition, antibacterial ability of Au/C core-shell composite was observed by atomic force microscope. Results demonstrated that gold homogeneously supported on the surface of carbon spheres without aggregation and showed efficient antibacterial abilities.

  20. Magnetic C-C@Fe3O4 double-shelled hollow microspheres via aerosol-based Fe3O4@C-SiO2 core-shell particles.

    Zhu, Yangzhi; Li, Xiangcun; He, Gaohong; Qi, Xinhong


    Magnetic C-C@Fe3O4 hollow microspheres were prepared by using aerosol-based Fe3O4@C-SiO2 core-shell particles as templates. The magnetic double-shelled microspheres efficiently worked as carriers to load Pt nanoparticles, thus making the catalyst recyclable and reusable.

  1. Design and synthesis of highly luminescent near-infrared-emitting water-soluble CdTe/CdSe/ZnS core/shell/shell quantum dots.

    Zhang, Wenjin; Chen, Guanjiao; Wang, Jian; Ye, Bang-Ce; Zhong, Xinhua


    Applications of water-dispersible near-infrared (NIR)-emitting quantum dots (QDs) have been hampered by their instability and low photoluminescence (PL) efficiencies. In this paper, water-soluble highly luminescent NIR-emitting QDs were developed through constructing CdTe/CdSe/ZnS core/shell/shell nanostructure. The CdTe/CdSe type-II structure yields the QDs with NIR emission. By varying the size of CdTe cores and the thickness of the CdSe shell, the emission wavelength of the obtained nanostructure can span from 540 to 825 nm. In addition, the passivation of the ZnS shell with a substantially wide bandgap confines the excitons within the CdTe/CdSe interface and isolates them from the solution environment and consequently improves the stability of the nanostructure, especially in aqueous media. An effective shell-coating route was developed for the preparation of CdTe/CdSe core/shell nanostructures by selecting capping reagents with a strong coordinating capacity and adopting a low temperature for shell deposition. An additional ZnS shell was deposited around the outer layer of CdTe/CdSe QDs to form the core/shell/shell nanostructure through the decomposition of single molecular precursor zinc diethyldithiocarbamate in the crude CdTe/CdSe reaction solution. The water solubilization of the initially oil-soluble CdTe/CdSe/ZnS QDs was achieved through ligand replacement by 3-mercaptopropionic acid. The as-prepared water-soluble CdTe/CdSe/ZnS QDs possess PL quantum yields as high as 84% in aqueous media, which is one of the best results for the luminescent semiconductor nanocrystals.

  2. Prevalence of anisotropic shell growth in rare earth core-shell upconversion nanocrystals.

    Zhang, Chao; Lee, Jim Yang


    Through a series of carefully executed experiments, we discovered the prevalence of anisotropic shell growth in many upconversion NaREF4 systems caused by a combination of factors: selective adsorption of ligands on the core surface due to the core crystal structure, ligand etching, and the lattice mismatch between core and shell components. This could lead to incomplete shell formation in core-shell nanocrystals under certain conditions. Shell growth is always faster in the a and b crystallographic directions than in the c direction. In the case of a larger lattice mismatch between the core and shell, shell growth only occurs in the a and b directions resulting in an oblong core-shell structure. These findings are useful for rationalizing shell-dependent emission properties, understanding the emission mechanisms in complex core-shell nanostructures, and for creating accurate models of core-shell designs for multifunctionality and optimal performance in applications.

  3. Stability of facetted translation shells

    Almegaard, Henrik; Vanggaard, Ole


    This article is discussing the spatial stability i.e. rigidity of double curved shell surfaces under different support conditions. It is based upon a method developed by Henrik Almegaard, as part of the theory concerning the stringer system (ALM04a).......This article is discussing the spatial stability i.e. rigidity of double curved shell surfaces under different support conditions. It is based upon a method developed by Henrik Almegaard, as part of the theory concerning the stringer system (ALM04a)....

  4. Learning Shell scripting with Zsh

    Festari, Gaston


    A step-by-step tutorial that will teach you, through real-world examples, how to configure and use Zsh and its various features. If you are a system administrator, developer, or computer professional involved with UNIX who are looking to improve on their daily tasks involving the UNIX shell, ""Learning Shell Scripting with Zsh"" will be great for you. It's assumed that you have some familiarity with an UNIX command-line interface and feel comfortable with editors such as Emacs or vi.

  5. Design of a stabilizing shell for KTX

    You, Wei [CAS Key Laboratory of Geospace Environment, Department of Modern Physics, University of Science and Technology of China, Hefei 230026 (China); Li, Hong, E-mail: [CAS Key Laboratory of Geospace Environment, Department of Modern Physics, University of Science and Technology of China, Hefei 230026 (China); Tan, Mingsheng; Lu, Mingjian; Wu, Yanqi; Mao, Wenzhe; Bai, Wei; Tu, Cui; Luo, Bing; Li, Zichao; Adil, Yolbarsop; Hu, Jintong [CAS Key Laboratory of Geospace Environment, Department of Modern Physics, University of Science and Technology of China, Hefei 230026 (China); Song, Yuntao; Yang, Qingxi; Zhang, Ping [Institute of Plasma Physics Chinese Academy of Sciences, Hefei 230026 (China); Xie, Jinlin; Lan, Tao; Liu, Adi [CAS Key Laboratory of Geospace Environment, Department of Modern Physics, University of Science and Technology of China, Hefei 230026 (China); Ding, Weixing [CAS Key Laboratory of Geospace Environment, Department of Modern Physics, University of Science and Technology of China, Hefei 230026 (China); Department of Physics and Astronomy, University of California at Los Angeles, Los Angeles, CA 90095 (United States); Xiao, Chijin [CAS Key Laboratory of Geospace Environment, Department of Modern Physics, University of Science and Technology of China, Hefei 230026 (China); Department of Physics and Engineering Physics, University of Saskatchewan, SK S7 N 5N2 (Canada); and others


    The conductive shell in reversed field pinch devices plays an important role in controlling plasma and in suppressing MHD instabilities. The shell in the Keda torus experiment reversed field pinch (KTX-RFP) device includes a 6-mm stainless steel vacuum chamber and a 1.5-mm stabilizing copper shell. This stabilizing shell has both poloidal and toroidal gaps to allow a coupling of electromagnetic energy to the plasma. Nevertheless, any gaps in this shell generate error fields. A 3D electromagnetic field model has been used to study effects of the gap on the shell. Using off-center current filaments instead of the distributed plasma current density, numerical analyses render the induced current distribution on the stabilizing shell and the resultant error field distribution at a specific frequency. From the analyses and comparisons of different configurations for the stabilizing shell, a suitable shell design is chosen consisting of three sections: one primary shell, two poloidal shield shells, and two toroidal shield shells. Moreover, the time evolution of the magnetic field inside and outside the stabilizing shell was obtained for this design and the dependence of the magnetic field penetration time on mode number and location has been investigated.

  6. Microfluidic synthesis of Ag@Cu2O core-shell nanoparticles with enhanced photocatalytic activity.

    Tao, Sha; Yang, Mei; Chen, Huihui; Ren, Mingyue; Chen, Guangwen


    A microfluidic-based method for the continuous synthesis of Ag@Cu2O core-shell nanoparticles (NPs) has been developed. It only took 32s to obtain Ag@Cu2O core-shell NPs, indicating a high efficiency of this microfluidic-based method. Triangular Ag nanoprisms were employed as the cores for the overgrowth of Cu2O through the reduction of Cu(OH)4(2-) with ascorbic acid. The as-synthesized samples were characterized by XRD, TEM, SEM, HAADF-STEM, EDX, HRTEM, UV-vis spectra and N2 adsorption-desorption. The characterization results revealed that the as-synthesized Ag@Cu2O core-shell NPs exhibited a well-defined core-shell nanostructure with a polycrystalline shell, which was composed of numbers of Cu2O domains epitaxially growing on the triangular Ag nanoprism. It was concluded that the synthesis parameters such as the molar ratio of trisodium citrate to AgNO3, H2O2 to AgNO3, NaOH to CuSO4, ascorbic acid to CuSO4 and AgNO3 to CuSO4 had significant effect on the synthesis of Ag@Cu2O core-shell NPs. Moreover, Ag@Cu2O core-shell NPs exhibited superior catalytic activity in comparison with pristine Cu2O NPs towards the visible light-driven degradation of methyl orange. This enhanced photocatalytic activity of Ag@Cu2O core-shell NPs was attributed to the larger BET surface area and improved charge separation efficiency. The trapping experiment indicated that holes and superoxide anion radicals were the major reactive species in the photodegradation of methyl orange over Ag@Cu2O core-shell NPs. In addition, Ag@Cu2O core-shell NPs showed no obvious deactivation in the cyclic test.

  7. The Design and Dynamics Performance Research of Pneumatic Hydraulic Coupled Suspension Strut%气液力耦合的新型悬架减振支柱设计与动力学性能研究

    江浩斌; 李龙晨; 叶燊辰


    Structure, basic working principle, method of damping adjusting and air-chamber volume adjusting for a new type suspension strut consisted of the air spring and the hydraulic shock absorber are introduced in this paper. A gas-liquid coupling dynamic model for the new type suspension strut was established. New front suspension strut of a passenger car was designed, the nonlinear dynamics performance of the strut, main influence factors and gas-liquid mechanical coupling relationship were analyzed by using simulation software. Bench test results indicate that testing results were very close to the simulation results, verifying that the design scheme of the new type suspension strut is feasible and the established gas-liquid coupled model is correct.%介绍了一种空气弹簧力与减振器阻尼力具有耦合关系的新型悬架减振支柱的结构设计方案、工作原理、阻尼调节和空气弹簧气室容积调节方法,建立了新型减振支柱气、液力耦合动力学模型。设计了某乘用车前悬架的新型减振支柱,通过仿真计算分析了该减振支柱的非线性动力学性能、主要影响因素及气液力耦合作用关系。台架试验表明,新型减振支柱作用力的仿真结果与试验结果接近,验证了新型减振支柱设计方案的可行性和气液力耦合动力学模型的正确性。

  8. Head to head comparison of optical coherence tomography, intravascular ultrasound echogenicity and virtual histology for the detection of changes in polymeric struts over time

    Brugaletta, Salvatore; Gomez-Lara, Josep; Bruining, Nico


    To analyse and to compare the changes in the various optical coherence tomography (OCT), echogenicity and intravascular ultrasound virtual histology (VH) of the everolimus-eluting bioresorbable scaffold (ABSORB) degradation parameters during the first 12 months after ABSORB implantation. In the A......To analyse and to compare the changes in the various optical coherence tomography (OCT), echogenicity and intravascular ultrasound virtual histology (VH) of the everolimus-eluting bioresorbable scaffold (ABSORB) degradation parameters during the first 12 months after ABSORB implantation....... In the ABSORB study, changes in the appearance of the ABSORB scaffold were monitored over time using various intracoronary imaging modalities. The scaffold struts exhibited a progressive change in their black core area by OCT, in their ultrasound derived grey level intensity quantified by echogenicity...

  9. An e-Purchasing System Based on Struts and Hibernate%基于Struts和Hibernate的电子申购系统

    李伟镰; 卢建朱


    通过对现代物资申购作业的系统分析,在J2EE的B/S应用架构下,以Struts 作为表现层框架、Hibernate作为数据持久层框架,设计了一个电子申购系统.并利用柔性构件技术、XML数据标准和Java语言实现.该系统效率高、职责明确、反馈快捷、方便,并具有良好的可扩展性、实用性和可维护性.

  10. 基于云平台和struts技术的考场助手%An Examination Room Assistant Based on Cloud Platform and struts Technology

    余丙军; 周继香; 吴肖; 任红瑛


    本文介绍了云计算技术和struts技术,分析了当前考试相关的各个环节可能出现的问题和不足,设计并实现了考场助手系统以解决考场中可能发生的问题,并对该考场助手系统做了详细的介绍。%This paper introduces the technology of cloud computing and struts technology, analyzes the possible problems and deficiencies of the current examination, designs and implements the examination room assistant system to solve the possible problems in the examination room, and introduces the room assistant system in detail.

  11. Method and apparatus for an inflatable shell

    Johnson, Christopher J. (Inventor)


    A method of assembling an inflatable shell of a structure comprises folding a plurality of shell sections about a set of fold lines and integrating the plurality of shell sections together with one another to form the shell. In another embodiment, an inflatable shell comprises a plurality of shell sections, each shell section having two pairs of fold lines for folding into stowage comprising a first gore section having a plurality of first gore panels layered and collectively folded about at a first set of fold lines. Each layer of the first gore panels and second gore panels are configured such that, once the first gore panel and second gore panel are attached to one another at the respective side edges of each panel, the lines of attachment forming a second set of fold lines for the shell section. A system and method for fabricating gore panels is also disclosed.

  12. Statistical mechanics of thin spherical shells

    Kosmrlj, Andrej


    We explore how thermal fluctuations affect the mechanics of thin amorphous spherical shells. In flat membranes with a shear modulus, thermal fluctuations increase the bending rigidity and reduce the in-plane elastic moduli in a scale-dependent fashion. This is still true for spherical shells. However, the additional coupling between the shell curvature, the local in-plane stretching modes and the local out-of-plane undulations, leads to novel phenomena. In spherical shells thermal fluctuations produce a radius-dependent negative effective surface tension, equivalent to applying an inward external pressure. By adapting renormalization group calculations to allow for a spherical background curvature, we show that while small spherical shells are stable, sufficiently large shells are crushed by this thermally generated "pressure". Such shells can be stabilized by an outward osmotic pressure, but the effective shell size grows non-linearly with increasing outward pressure, with the same universal power law expone...

  13. Dual role of circulating endothelial progenitor cells in stent struts endothelialisation and neointimal regrowth: a substudy of the IN-PACT CORO trial.

    De Maria, Giovanni Luigi; Porto, Italo; Burzotta, Francesco; Brancati, Marta Francesca; Trani, Carlo; Pirozzolo, Giancarlo; Leone, Antonio Maria; Niccoli, Giampaolo; Prati, Francesco; Crea, Filippo


    Endothelialisation is a crucial event after percutaneous coronary intervention (PCI). Endothelial progenitor cells (EPCs) are bone marrow derived elements with reparative properties. We aimed to assess the relationship between circulating EPC levels and stent neointimal hyperplasia (NIH) using frequency domain optical coherence tomography (FD-OCT). Patients undergoing elective PCI to native vessels and randomised to bare metal stent (BMS) alone versus BMS plus drug coated balloon (DCB) were included. At six months, angiographic follow-up and FD-OCT were performed to measure percentage neointimal hyperplasia volume obstruction (%NIHV), and percentage of uncovered stent struts (%US). Venous blood samples were obtained before the procedure and at six months to detect CD34+CD45dimKDR+ EPC levels. Twenty patients were enrolled. A significant relationship was observed between baseline EPC levels and %NIHV (R: 0.63, p: 0.03) and %US (R: -0.56, p: 0.01) at follow-up. Both EPC levels and DCB use were independently related to %NIHV (β: 0.55; p < 0.001 and β: -0.51; p: 0.001, respectively), while only EPC levels were independently associated to %US (β: -0.52; p: 0.01). Higher %NIHV (p: 0.004) and lower %US (p: 0.005) were observed in patients with stable or increasing EPC level. Our study shows a relationship between EPC levels and stent strut coverage, supporting a dual role for these cells in favouring stent endothelialisation but also NIH growth. Copyright © 2014 Elsevier Inc. All rights reserved.

  14. Solving the Issue of Restenosis After Stenting of Intracranial Stenoses: Experience with Two Thin-Strut Drug-Eluting Stents (DES)—Taxus Element™ and Resolute Integrity™

    Kurre, Wiebke, E-mail:; Aguilar-Pérez, Marta [Klinikum Stuttgart, Klinik für Diagnostische und Interventionelle Neuroradiologie (Germany); Fischer, Sebastian [Universitätsklinikum Knappschaftskrankenhaus Bochum GmbH, Institut für Diagnostische und Interventionelle Radiologie, Neuroradiologie und Nuklearmedizin (Germany); Arnold, Guy [Klinikverbund Südwest, Klinikum Sindelfingen, Klinik für Neurologie (Germany); Schmid, Elisabeth; Bäzner, Hansjörg [Klinikum Stuttgart, Klinik für Neurologie (Germany); Henkes, Hans [Klinikum Stuttgart, Klinik für Diagnostische und Interventionelle Neuroradiologie (Germany)


    PurposeThin-strut, flexible DES are suitable for intracranial stenting and may improve long-term vessel patency. The purpose of this study was to report our experience with two new-generation DES for the treatment of intracranial atherosclerotic disease.Patients and MethodsWe retrospectively reviewed all patients treated with Taxus Element™ or Resolute Integrity™ stent for an intracranial atherosclerotic stenosis between March 2011 and August 2013. Technical success was defined as the ability to deploy the device at the desired location and reduce the degree of stenosis below 50 %. All procedure-related strokes were recorded. Control angiography was scheduled after 6 weeks, 3, 6, and 12 months and yearly thereafter. A luminal narrowing ≥50 % was regarded as a restenosis. Stroke recurrence in the territory of the treated artery was reported.ResultsIn the defined period we treated 101 patients harboring 117 intracranial stenoses. The procedure was successful in 100 (85.5 %) lesions. Procedure-related strokes occurred in 10 (9.9 %) patients with a permanent morbidity in 3 (3.0 %). Follow-up angiography was available for 83 of 100 (83.0 %) successfully treated lesions with an average of 355 days (IQR 153–482 days). Three (3.6 %) asymptomatic restenoses were detected. All occurred after treatment with Resolute Integrity™, none after Taxus Element™ (p = 0.059). New strokes in the territory of the treated artery were encountered in 2 (2.6 %) occasions.ConclusionThin-strut DES improve long-term patency and reduce the risk of subsequent stroke. Differences between devices may exist. Feasibility is comparable to bare-metal balloon-mounted stents and procedure-related strokes occurred within the expected range.

  15. Shell Global Solutions Ready to Benefit China


    @@ Thanks to rising oil prices, Global oil giant Royal Dutch Shell has made huge profits - $9 billion - last quarter. Yet the oil giant's main profits come from the exploration of crude oil. Shell Global Solution (SGS),a unit of Shell, is also focusing on providing advanced technology to help Shell's petroleum-related industry segments and its third-party customers to deal with the high price of fossil fuel.

  16. Euclidean Approach for Entropy of Black Shells

    S., J Robel Arenas


    We introduce the concept of black shell, consisting on a massive thin spherical shell contracting toward its gravitational radius from the point of view of an external observer far from the shell, in order to effectively model the gravitational collapse. Considering complementary description of entanglement entropy of a black shell and according to Gibbons-Hawking Euclidean approach, we calculate the Bekenstein-Hawking entropy retrieving horizon integral and discarding boundary at infinity.

  17. Shell theorem for spontaneous emission

    Kristensen, Philip Trøst; Mortensen, Jakob Egeberg; Lodahl, Peter;


    and therefore is given exactly by the dipole approximation theory. This surprising result is a spontaneous emission counterpart to the shell theorems of classical mechanics and electrostatics and provides insights into the physics of mesoscopic emitters as well as great simplifications in practical calculations....

  18. Observability inequalities for thin shells

    柴树根; 姚鹏飞


    We consider the exact controllability problem from boundary for thin shells. Under some check-able geometric assumptions on the middle surface, we establish the observability inequalities via the Bochnertechnique for the Dirichlet control and the Neumann control problems. We also give several examples to verifythe geometric assumptions.

  19. Shell morphology of core-shell latexes based on conductive polymers

    Huijs, F.M; Vercauteren, F.F.; de Ruiter, B.; Kalicharan, D; Hadziioannou, G

    Core-shell latexes with a conductive shell can be used to prepare transparent conducting layers. We have focussed on the relation between the conducting polymer content and the shell morphology and on its influence on conductivity. At low polypyrrole (PPy) concentrations the shell has a smooth


    LIU Lijun; ZHANG Zhiyi; HUA Hongxing; ZHANG Yi


    Active constrained layer damping (ACLD) combines the simplicity and reliability of passive damping with the light weight and high efficiency of active actuators to obtain high damping over a wide frequency band. A fluid-filled prismatic shell is set up to investigate the validity and efficiency of ACLD treatments in the case of fluid-structure interaction. By using state subspace identification method, modal parameters of the ACLD system are identified and a state space model is established subsequently for the design of active control laws. Experiments are conducted to the fluid-filled prismatic shell subjected to random and impulse excitation, respectively. For comparison, the shell model without fluid interaction is experimented as well. Experimental results have shown that the ACLD treatments can suppress vibration of the fluid-free and fluid-filled prismatic shell effectively. Under the same control gain, vibration attenuation is almost the same in both cases.

  1. 21 CFR 886.3800 - Scleral shell.


    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Scleral shell. 886.3800 Section 886.3800 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES OPHTHALMIC DEVICES Prosthetic Devices § 886.3800 Scleral shell. (a) Identification. A scleral shell is...

  2. Shell China Promotes Localization of Employees


    @@ Shell China Limited's Executive Chairman Lim Haw Kuang is unquestionably an effective reformer for the Beijing-based company. He localized Shell China Limited's leadership team with Chinese employees going from zero to a majority in three years, and engineered the turnaround of Shell's business in China.

  3. 7 CFR 983.29 - Shelled pistachios.


    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Shelled pistachios. 983.29 Section 983.29 Agriculture... and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE PISTACHIOS GROWN IN CALIFORNIA, ARIZONA, AND NEW MEXICO Definitions § 983.29 Shelled pistachios. Shelled pistachios means...

  4. Shell Expands Polystyrene Joint Venture in China


    @@ Shell China Ltd. and Shell China Holdings BV, both wholly owned subsidiaries and part of the Royal Dutch/Shell Group of Companies, have signed a joint-venture agreement with Jinling Petrochemical Corporation (JPC) on October 17, 1997, in Nanjing, the East China's Jiangsu Province.

  5. Protein profiles of hatchery egg shell membrane

    Background: Eggshells, which consist largely of calcareous outer shell and shell membranes, constitute a significant part of poultry hatchery waste. The shell membranes (ESM) not only contain proteins that originate from egg whites but also from the developing embryos and different contaminants of m...

  6. Effective Finite Elements for Shell Analysis.


    conjunction with a shallow shell theory . It 2 should be noteJ that contrary to the results of earlier investigators [12,19], use of a shallow shell theory in...the inadequacy of the shallow shell theory for the relatively deep element emerging from such a coarse mesh. A considerable improvement is obtained

  7. Stochastic Finite Element Analysis of Plate and Shell Construction


    The response of random plate and shell construction is analyzed with the stochastic finite element method (SFEM). Random material properties and geometric dimensions of construction are involved in this paper. A simplified isoparametric local average model is used to describe the random field. Numerical results of the examples indicate that the approach presented herein is an economical and efficient solution for such an analysis compared with Monte Carlo simulation (MCS).

  8. Vibrations of cantilevered circular cylindrical shells Shallow versus deep shell theory

    Lee, J. K.; Leissa, A. W.; Wang, A. J.


    Free vibrations of cantilevered circular cylindrical shells having rectangular planforms are studied in this paper by means of the Ritz method. The deep shell theory of Novozhilov and Goldenveizer is used and compared with the usual shallow shell theory for a wide range of shell parameters. A thorough convergence study is presented along with comparisons to previously published finite element solutions and experimental results. Accurately computed frequency parameters and mode shapes for various shell configurations are presented. The present paper appears to be the first comprehensive study presenting rigorous comparisons between the two shell theories in dealing with free vibrations of cantilevered cylindrical shells.

  9. Gasification of ‘Loose’ Groundnut Shells in a Throathless Downdraft Gasifier

    Aondoyila Kuhe


    Full Text Available In this paper, gasification potential of biomass residue was investigated using a laboratory scale throatless downdraft gasifier. Experimental results of groundnut shell was gasified in the throatless downdraft gasifier to produce a clean gas with a calorific value of around 5.92 MJ/Nm3 and a combustible fraction of 45% v/v. Low moisture (8.6% and ash content (3.19% are the main advantages of groundnut shells for gasification. It is suggested that gasification of shell waste products is a clean energy alternative to fossil fuels. The product gas can be used efficiently for heating and possible usage in internal combustion engines.

  10. Stochastic estimation of level density in nuclear shell-model calculations

    Shimizu Noritaka


    Full Text Available An estimation method of the nuclear level density stochastically based on nuclear shell-model calculations is introduced. In order to count the number of the eigen-values of the shell-model Hamiltonian matrix, we perform the contour integral of the matrix element of a resolvent. The shifted block Krylov subspace method enables us its efficient computation. Utilizing this method, the contamination of center-of-mass motion is clearly removed.

  11. Modeling of absorption and scattering properties of core -shell nanoparticles for application as nanoantenna in optical domain

    Devi, Jutika; Saikia, Rashmi; Datta, Pranayee


    The present paper describes the study of core-shell nanoparticles for application as nanoantenna in the optical domain. To obtain the absorption and extinction efficiencies as well as the angular distribution of the far field radiation pattern and the resonance wavelengths for these metal-dielectric, dielectric-metal and metal-metal core-shell nanoparticles in optical domain, we have used Finite Element Method based COMSOL Multiphysics Software and Mie Theory. From the comparative study of the extinction efficiencies of core-shell nanoparticles of different materials, it is found that for silica - gold core - shell nanoparticles, the resonant wavelength is greater than that of the gold - silver, silver-gold and gold-silica core - shell nanoparticles and also the radiation pattern of the silica-gold core-shell nanoparticle is the most suitable one from the point of view of directivity. The dielectric functions of the core and shell material as well as of the embedded matrix are extremely important and plays a very major role to tune the directivity and resonance wavelength. Such highly controllable parameters of the dielectric - metal core - shell nanoparticles make them suitable for efficient coupling of optical radiation into nanoscale structures for a broad range of applications in the field of communications.

  12. Pro Bash Programming Scripting the Linux Shell

    Johnson, Chris FA


    The bash shell is a complete programming language, not merely a glue to combine external Linux commands. By taking full advantage of shell internals, shell programs can perform as snappily as utilities written in C or other compiled languages. And you will see how, without assuming Unix lore, you can write professional bash 4.0 programs through standard programming techniques. *Complete bash coverage*Teaches bash as a programming language*Helps you master bash 4.0 features What you'll learn*Use the shell to write new utilities and accomplish most programming tasks.*Use shell parameter expansio

  13. Ultrabright Luminescence from Gold Nanoclusters: Rigidifying the Au(I)-Thiolate Shell.

    Pyo, Kyunglim; Thanthirige, Viraj Dhanushka; Kwak, Kyuju; Pandurangan, Prabhu; Ramakrishna, Guda; Lee, Dongil


    Luminescent nanomaterials have captured the imagination of scientists for a long time and offer great promise for applications in organic/inorganic light-emitting displays, optoelectronics, optical sensors, biomedical imaging, and diagnostics. Atomically precise gold clusters with well-defined core-shell structures present bright prospects to achieve high photoluminescence efficiencies. In this study, gold clusters with a luminescence quantum yield greater than 60% were synthesized based on the Au22(SG)18 cluster, where SG is glutathione, by rigidifying its gold shell with tetraoctylammonium (TOA) cations. Time-resolved and temperature-dependent optical measurements on Au22(SG)18 have shown the presence of high quantum yield visible luminescence below freezing, indicating that shell rigidity enhances the luminescence quantum efficiency. To achieve high rigidity of the gold shell, Au22(SG)18 was bound to bulky TOA that resulted in greater than 60% quantum yield luminescence at room temperature. Optical measurements have confirmed that the rigidity of gold shell was responsible for the luminescence enhancement. This work presents an effective strategy to enhance the photoluminescence efficiencies of gold clusters by rigidifying the Au(I)-thiolate shell.

  14. Shell Model Depiction of Isospin Mixing in sd Shell

    Lam, Yi Hua; Smirnova, Nadya A. [CENBG (CNRS/IN2P3 - Universite Bordeaux 1) Chemin du Solarium, 33175 Gradignan (France); Caurier, Etienne [IPHC, IN2P3-CNRS et Universite Louis Pasteur, 67037 Strasbourg (France)


    We constructed a new empirical isospin-symmetry breaking (ISB) Hamiltonian in the sd(1s{sub 1/2}, 0d{sub 5/2} and 0d{sub 3/2}) shell-model space. In this contribution, we present its application to two important case studies: (i){beta}-delayed proton emission from {sup 22}Al and (ii) isospin-mixing correction to superallowed 0{sup +}{yields}0{sup +}{beta}-decay ft-values.

  15. Removal of Arsenic with Oyster Shell: Experimental Measurements

    Md. Atiqur Rahman, , and


    Full Text Available Oyster shell has tremendous potential as a remediation material for the removal of arsenic from groundwater. A single arsenic removal system was developed with oyster shell for tube well water containing arsenic. The system removes arsenic from water by adsorption through fine oyster shell. Various conditions that affect the adsorption/desorption of arsenic were investigated. Adsorption column methods showed the removal of As(III under the following conditions: initial As concentration, 100 µg /L; oyster shell amount, 6 g; particle size, <355µm ; treatment flow rate, 1.7 mL/min; and pH 6.5. Arsenic concentration of the treated water were below the Bangladesh drinking water standard of 50 µg/L for As. The desorption efficiencies with 2M of KOH after the treatment of groundwater were in the range of 80-83%. A combination of techniques was used to measure the pH, conductivity, cations and anions. The average concentrations of other inorganic constituents of health concern (Na, K, Ca, Mg and Fe in treated water were below their respective WHO guideline for drinking. The present study might provide new avenues to achieve the arsenic concentrations required for drinking water recommended by Bangladesh and the World Health Organization (WHO.

  16. Design rules for core/shell nanowire resonant emitters

    Kim, Da-Som; Kim, Sun-Kyung


    We study design principles to boost the extraction of light from core/shell GaN nanowire optical emitters. A full-vectorial electromagnetic simulation reveals that the extraction efficiency of an emitter within a nanowire cavity depends strongly on its position; the efficiency becomes maximized as the emitter's location approaches the center of the structure. The total extraction of light is sinusoidally modulated by the nanowire diameter, which is directly correlated with optical resonances. The introduction of a conformal dielectric coating on a nanowire leads to a dramatic enhancement in the extraction efficiency, which results from an increase in side emission owing to an optical antenna effect. A simple high-refractive-index dielectric coating approximately doubles the total extraction efficiency of a nanowire LED. These numerical findings will be valuable in providing strategies for high-efficiency nanowire-based optical emitters.

  17. Recent developments in anisotropic heterogeneous shell theory

    Grigorenko, Alexander Ya; Grigorenko, Yaroslav M; Vlaikov, Georgii G


    This volume focuses on the relevant general theory and presents some first applications, namely those based on classical shell theory. After a brief introduction, during which the history and state-of-the-art are discussed, the first chapter presents the mechanics of anisotropic heterogeneous shells, covering all relevant assumptions and the basic relations of 3D elasticity, classical and refined shell models. The second chapter examines the numerical techniques that are used, namely discrete orthogonalization, spline-collocation and Fourier series, while the third highlights applications based on classical theory, in particular, the stress-strain state of shallow shells, non-circular shells, shells of revolution, and free vibrations of conical shells. The book concludes with a summary and an outlook bridging the gap to the second volume.

  18. Turbine blade with spar and shell

    Davies, Daniel O [Palm City, FL; Peterson, Ross H [Loxahatchee, FL


    A turbine blade with a spar and shell construction in which the spar and the shell are both secured within two platform halves. The spar and the shell each include outward extending ledges on the bottom ends that fit within grooves formed on the inner sides of the platform halves to secure the spar and the shell against radial movement when the two platform halves are joined. The shell is also secured to the spar by hooks extending from the shell that slide into grooves formed on the outer surface of the spar. The hooks form a serpentine flow cooling passage between the shell and the spar. The spar includes cooling holes on the lower end in the leading edge region to discharge cooling air supplied through the platform root and into the leading edge cooling channel.

  19. Indentation of Ellipsoidal and Cylindrical Elastic Shells

    Vella, Dominic


    Thin shells are found in nature at scales ranging from viruses to hens\\' eggs; the stiffness of such shells is essential for their function. We present the results of numerical simulations and theoretical analyses for the indentation of ellipsoidal and cylindrical elastic shells, considering both pressurized and unpressurized shells. We provide a theoretical foundation for the experimental findings of Lazarus etal. [following paper, Phys. Rev. Lett. 109, 144301 (2012)PRLTAO0031-9007] and for previous work inferring the turgor pressure of bacteria from measurements of their indentation stiffness; we also identify a new regime at large indentation. We show that the indentation stiffness of convex shells is dominated by either the mean or Gaussian curvature of the shell depending on the pressurization and indentation depth. Our results reveal how geometry rules the rigidity of shells. © 2012 American Physical Society.

  20. Controlled drug release from lung-targeted nanocarriers via chemically mediated shell permeabilisation.

    Chen, Hanpeng; Woods, Arcadia; Forbes, Ben; Jones, Stuart


    Nanocarriers can aid therapeutic agent administration to the lung, but controlling drug delivery from these systems after deposition in the airways can be problematic. The aim of this study was to evaluate if chemically mediated shell permeabilisation could help manipulate the rate and extent of nanocarrier drug release. Rifampicin was loaded into lipid shell (loading efficiency 41.0±11.4%, size 50nm) and polymer shell nanocarriers (loading efficiency 25.9±2.3%, size 250nm). The drug release at pH 7.4 (lung epithelial pH) and 4.2 (macrophage endosomal pH) with and without the chemical permeabilisers (Pluronic L62D - lipid nanocarriers; H(+)- polymer nanocarriers) was then tested. At pH 7.4 the presence of the permeabilisers increased nanocarrier drug release rate (from 3.2μg/h to 6.8μg/h for lipid shell nanocarriers, 2.3μg/h to 3.4μg/h for polymer shell nanocarriers) and drug release extent (from 50% to 80% for lipid shell nanocarriers, from 45% to 76% for polymer shell nanocarriers). These effects were accompanied by lipid nanocarrier distension (from 50 to 240nm) and polymer shell hydrolysis. At pH 4.2 the polymer nanocarriers did not respond to the permeabiliser, but the lipid nanocarrier maintained a robust drug release enhancement response and hence they demonstrated that the manipulation of controlled drug release from lung-targeted nanocarriers was possible through chemically mediated shell permeabilisation.

  1. Intra- and interobserver reliability and intra-catheter reproducibility using frequency domain optical coherence tomography for the evaluation of morphometric stent parameters and qualitative assessment of stent strut coverage

    Antonsen, Lisbeth, E-mail:; Thayssen, Per; Junker, Anders; Veien, Karsten Tange; Hansen, Henrik Steen; Hansen, Knud Nørregaard; Hougaard, Mikkel; Jensen, Lisette Okkels


    Purpose: Frequency-domain optical coherence tomography (FD-OCT) is a high-resolution imaging tool (~ 10–15 μm), which enables near-histological in-vivo images of the coronary vessel wall. The use of the technique is increasing, both for research- and clinical purposes. This study sought to investigate the intra- and interobserver reliability, as well as the intra-catheter reproducibility of quantitative FD-OCT-assessment of morphometric stent parameters and qualitative FD-OCT-evaluation of strut coverage in 10 randomly selected 6-month follow-up Nobori® biolimus-eluting stents (N-BESs). Methods: Ten N-BESs (213 cross sectional areas (CSAs) and 1897 struts) imaged with OCT 6 months post-implantation were randomly selected and analyzed by 2 experienced analysts, and the same 10 N-BESs were analyzed by one of the analysts 3 months later. Further, 2 consecutive pullbacks randomly performed in another 10 N-BESs (219 CSAs and 1860 struts) were independently assessed by one of the analysts. Results: The intraobserver variability with regard to relative difference of mean luminal area and mean stent area at the CSA-level was very low: 0.1% ± 1.4% and 0.5% ± 3.2%. Interobserver variability also proved to be low: − 2.1% ± 3.3% and 2.1% ± 4.6%, and moreover, very restricted intra-catheter variation was observed: 0.02% ± 6.8% and − 0.18% ± 5.2%. The intraobserver-, interobserver- and intra-catheter reliability for the qualitative evaluation of strut coverage was found to be: kappa (κ) = 0.91 (95% confidence interval (CI): 0.88–0.93, p < 0.01), κ = 0.88 (95% CI: 0.85–0.91, p < 0.01), and κ = 0.73 (95% CI: 0.68–0.78, p < 0.01), respectively. Conclusions: FD-OCT is a reproducible and reliable imaging tool for quantitative evaluation of stented coronary segments, and for qualitative assessment of strut coverage. - Highlights: • Frequency-domain optical coherence tomography (FD-OCT) is increasingly adopted in the catherization laboratories. • This

  2. Shell Evolutions and Nuclear Forces

    Sorlin, O


    During the last 30 years, and more specifically during the last 10 years, many experiments have been carried out worldwide using different techniques to study the shell evolution of nuclei far from stability. What seemed not conceivable some decades ago became rather common: all known magic numbers that are present in the valley of stability disappear far from stability and are replaced by new ones at the drip line. By gathering selected experimental results, beautifully consistent pictures emerge, that very likely take root in the properties of the nuclear forces.The present manuscript describes some of these discoveries and proposes an intuitive understanding of these shell evolutions derived from observations. Extrapolations to yet unstudied regions, as where the explosive r-process nucleosynthesis occurs, are proposed. Some remaining challenges and puzzling questions are also addressed.

  3. Glass shell manufacturing in space

    Nolen, R. L.; Downs, R. L.; Ebner, M. A.


    Highly-uniform, hollow glass spheres, which are used for inertial-confinement fusion targets, are formed from metal-organic gel powder feedstock in a drop-tower furnace. The modelling of this gel-to-sphere transformation has consisted of three phases: gel thermochemistry, furnance-to-gel heat transfer, and gravity-driven degradation of the concentricity of the molten shell. The heat transfer from the furnace to the free-falling gel particle was modelled with forced convection. The gel mass, dimensions, and specific heat as well as furnace temperature profile and furnace gas conductivity, were controlled variables. This model has been experimentally verified. In the third phase, a mathematical model was developed to describe the gravity-driven degradation of concentricity in molten glass shells.

  4. Deformed two center shell model

    Gherghescu, R A


    A highly specialized two-center shell model has been developed accounting for the splitting of a deformed parent nucleus into two ellipsoidaly deformed fragments. The potential is based on deformed oscillator wells in direct correspondance with the shape change of the nuclear system. For the first time a potential responsible for the necking part between the fragments is introduced on potential theory basis. As a direct consequence, spin-orbit {\\bf ls} and {\\bf l$^2$} operators are calculated as shape dependent. Level scheme evolution along the fission path for pairs of ellipsoidaly deformed fragments is calculated. The Strutinsky method yields the shell corrections for different mass asymmetries from the superheavy nucleus $^{306}$122 and $^{252}$Cf all along the splitting process.

  5. Stochastic Analysis of Cylindrical Shell

    Grzywiński Maksym


    Full Text Available The paper deals with some chosen aspects of stochastic structural analysis and its application in the engineering practice. The main aim of the study is to apply the generalized stochastic perturbation techniques based on classical Taylor expansion with a single random variable for solution of stochastic problems in structural mechanics. The study is illustrated by numerical results concerning an industrial thin shell structure modeled as a 3-D structure.

  6. Study on the Explicit Formula of the Triangular Flat Shell Element Based on the Analytical Trial Functions for Anisotropy Material

    Xiang-Rong Fu


    Full Text Available This paper presents a novel way to formulate the triangular flat shell element. The basic analytical solutions of membrane and bending plate problem for anisotropy material are studied separately. Combining with the conforming displacement along the sides and hybrid element strategy, the triangular flat shell elements based on the analytical trial functions (ATF for anisotropy material are formulated. By using the explicit integral formulae of the triangular element, the matrices used in proposed shell element are calculated efficiently. The benchmark examples showed the high accuracy and high efficiency.

  7. Asymptotic safety goes on shell

    Benedetti, Dario


    It is well known in quantum field theory that the off-shell effective action depends on the gauge choice and field parametrization used in calculating it. Nevertheless, the typical scheme in which the scenario of asymptotically safe gravity is investigated is an off-shell version of the functional renormalization group equation. Working with the Einstein-Hilbert truncation as a test bed, we develop a new scheme for the analysis of asymptotically safe gravity in which the on-shell part of the effective action is singled out and we show that the beta function for the essential coupling has no explicit gauge-dependence. In order to reach our goal, we introduce several technical novelties, including a different decomposition of the metric fluctuations, a new implementation of the ghost sector, and a new cut-off scheme. We find a non-trivial fixed point, with a value of the cosmological constant which is independent of the gauge-fixing parameters.

  8. Shape-tunable core-shell microparticles.

    Klein, Matthias K; Saenger, Nicolai R; Schuetter, Stefan; Pfleiderer, Patrick; Zumbusch, Andreas


    Colloidal polymer particles are an important class of materials finding use in both everyday and basic research applications. Tailoring their composition, shape, and functionality is of key importance. In this article, we describe a new class of shape-tunable core-shell microparticles. They are composed of a cross-linked polystyrene (PS) core and a poly(methyl methacrylate) (PMMA) shell of varying thickness. In the first step, we prepared highly cross-linked PS cores, which are subsequently transferred into a nonpolar dispersant. They serve as the seed dispersion for a nonaqueous dispersion polymerization to generate the PMMA shell. The shape of the particles can subsequently be manipulated. After the shell growth stage, the spherical PS/PMMA core-shell colloids exhibit an uneven and wrinkled surface. An additional tempering procedure allows for smoothing the surface of the core-shell colloids. This results in polymer core-shell particles with a perfectly spherical shape. In addition to this thermal smoothing of the PMMA shell, we generated a selection of shape-anisotropic core-shell particles using a thermomechanical stretching procedure. Because of the unique constitution, we can selectively interrogate molecular vibrations in the PS core or the PMMA shell of the colloids using nonlinear optical microscopy techniques. This is of great interest because no photobleaching occurs, such that the particles can be tracked in real space over long times.

  9. Analytic Solution to Shell Boundary – Value Problems

    Yu. I. Vinogradov


    Full Text Available Object of research is to find analytical solution to the shell boundary – value problems, i.e. to consider the solution for a class of problems concerning the mechanics of hoop closed shells strain.The objective of work is to create an analytical method to define a stress – strain state of shells under non-axisymmetric loading. Thus, a main goal is to derive the formulas – solutions of the linear ordinary differential equations with variable continuous coefficients.The partial derivative differential equations of mechanics of shells strain by Fourier's method of variables division are reduced to the system of the differential equations with ordinary derivatives. The paper presents the obtained formulas to define solutions of the uniform differential equations and received on their basis formulas to define a particular solution depending on a type of the right parts of the differential equations.The analytical algorithm of the solution of a boundary task uses an approach to transfer the boundary conditions to the randomly chosen point of an interval of changing independent variable through the solution of the canonical matrix ordinary differential equation with the subsequent solution of system of algebraic equations for compatibility of boundary conditions at this point. Efficiency of algorithm is based on the fact that the solution of the ordinary differential equations is defined as the values of Cauchy – Krylova functions, which meet initial arbitrary conditions.The results of researches presented in work are useful to experts in the field of calculus mathematics, dealing with solution of systems of linear ordinary differential equations and creation of effective analytical computing methods to solve shell boundary – value problems.

  10. Shell structure and orbit bifurcations in finite fermion systems

    Magner, A. G., E-mail:; Yatsyshyn, I. S. [National Academy of Sciences of Ukraine, Institute for Nuclear Research (Ukraine); Arita, K. [Nagoya Institute of Technology, Department of Physics (Japan); Brack, M. [University of Regensburg, Institute for Theoretical Physics (Germany)


    We first give an overview of the shell-correction method which was developed by V.M. Strutinsky as a practicable and efficient approximation to the general self-consistent theory of finite fermion systems suggested by A.B. Migdal and collaborators. Then we present in more detail a semiclassical theory of shell effects, also developed by Strutinsky following original ideas of M.C. Gutzwiller. We emphasize, in particular, the influence of orbit bifurcations on shell structure. We first give a short overview of semiclassical trace formulae, which connect the shell oscillations of a quantum system with a sum over periodic orbits of the corresponding classical system, in what is usually called the 'periodic orbit theory'. We then present a case study in which the gross features of a typical double-humped nuclear fission barrier, including the effects of mass asymmetry, can be obtained in terms of the shortest periodic orbits of a cavity model with realistic deformations relevant for nuclear fission. Next we investigate shell structures in a spheroidal cavity model which is integrable and allows for far-going analytical computation. We show, in particular, how period-doubling bifurcations are closely connected to the existence of the so-called 'superdeformed' energy minimum which corresponds to the fission isomer of actinide nuclei. Finally, we present a general class of radial power-law potentials which approximate well the shape of a Woods-Saxon potential in the bound region, give analytical trace formulae for it and discuss various limits (including the harmonic oscillator and the spherical box potentials).

  11. Fast ranking influential nodes in complex networks using a k-shell iteration factor

    Wang, Zhixiao; Zhao, Ya; Xi, Jingke; Du, Changjiang


    Identifying the influential nodes of complex networks is important for optimizing the network structure or efficiently disseminating information through networks. The k-shell method is a widely used node ranking method that has inherent advantages in performance and efficiency. However, the iteration information produced in k-shell decomposition has been neglected in node ranking. This paper presents a fast ranking method to evaluate the influence capability of nodes using a k-shell iteration factor. The experimental results with respect to monotonicity, correctness and efficiency have demonstrated that the proposed method can yield excellent performance on artificial and real world networks. It discriminates the influence capability of nodes more accurately and provides a more reasonable ranking list than previous methods.

  12. Kinetics of Hg(II) adsorption and desorption in calcined mussel shells.

    Peña-Rodríguez, Susana; Fernández-Calviño, David; Nóvoa-Muñoz, Juan Carlos; Arias-Estévez, Manuel; Núñez-Delgado, Avelino; Fernández-Sanjurjo, María José; Alvarez-Rodríguez, Esperanza


    The potential use of calcined mussel shells to purify water contaminated with mercury was evaluated. The Hg(II) adsorption and desorption kinetics were studied in batch-type and stirred-flow chamber experiments. The adsorption/desorption experiments revealed some differences between the batches of shells used. The batch of shells that displayed the greatest capacity to adsorb Hg(II), via a highly irreversible reaction, also contained more Fe and Al than the other batches. The results of the stirred-flow chamber experiments indicated a high degree of irreversibility in the process of Hg(II) adsorption in the mussel shell, and that Hg(II) was rapidly retained. The results of these experiments also revealed that the efficiency of depuration differed depending on the length of time that the system was used: when the system was operated for 55 min, depurating 162 mL of inflowing water g(-1) mussel shell, a 90% reduction in the initial concentration of Hg(II) was obtained; use of the system for 90 min, depurating 265 mL water g(-1) mussel shell, produced a 75% reduction in the initial Hg(II), and use of the system for 162.5 min, depurating 487 mL of water g(-1) mussel shell, resulted in a 50% reduction in the initial Hg(II).

  13. Intra- and interobserver reliability and intra-catheter reproducibility using frequency domain optical coherence tomography for the evaluation of morphometric stent parameters and qualitative assessment of stent strut coverage

    Antonsen, Lisbeth; Thayssen, Per; Junker, Anders;


    to investigate the intra- and interobserver reliability, as well as the intra-catheter reproducibility of quantitative FD-OCT-assessment of morphometric stent parameters and qualitative FD-OCT-evaluation of strut coverage in 10 randomly selected 6-month follow-up Nobori® biolimus-eluting stents (N-BESs). METHODS...... (CI): 0.88-0.93, pquantitative evaluation of stented coronary segments, and for qualitative assessment of strut coverage.......PURPOSE: Frequency-domain optical coherence tomography (FD-OCT) is a high-resolution imaging tool (~10-15μm), which enables near-histological in-vivo images of the coronary vessel wall. The use of the technique is increasing, both for research- and clinical purposes. This study sought...

  14. Enhanced Upconversion Luminescence in Yb3+/Tm3+-Codoped Fluoride Active Core/Active Shell/Inert Shell Nanoparticles through Directed Energy Migration

    Hailong Qiu


    Full Text Available The luminescence efficiency of lanthanide-doped upconversion nanoparticles is of particular importance for their embodiment in biophotonic and photonic applications. Here, we show that the upconversion luminescence of typically used NaYF4:Yb3+30%/Tm3+0.5% nanoparticles can be enhanced by ~240 times through a hierarchical active core/active shell/inert shell (NaYF4:Yb3+30%/Tm3+0.5%/NaYbF4/NaYF4 design, which involves the use of directed energy migration in the second active shell layer. The resulting active core/active shell/inert shell nanoparticles are determined to be about 11 times brighter than that of well-investigated (NaYF4:Yb3+30%/Tm3+0.5%/NaYF4 active core/inert shell nanoparticles when excited at ~980 nm. The strategy for enhanced upconversion in Yb3+/Tm3+-codoped NaYF4 nanoparticles through directed energy migration might have implications for other types of lanthanide-doped upconversion nanoparticles.

  15. Enhanced photocurrent and dynamic response in vertically aligned In₂S₃/Ag core/shell nanorod array photoconductive devices.

    Cansizoglu, Hilal; Cansizoglu, Mehmet F; Watanabe, Fumiya; Karabacak, Tansel


    Enhanced photocurrent values were achieved through a semiconductor-core/metal-shell nanorod array photoconductive device geometry. Vertically aligned indium sulfide (In2S3) nanorods were formed as the core by using glancing angle deposition technique (GLAD). A thin silver (Ag) layer is conformally coated around nanorods as the metallic shell through a high pressure sputter deposition method. This was followed by capping the nanorods with a metallic blanket layer of Ag film by utilizing a new small angle deposition technique combined with GLAD. Radial interface that was formed by the core/shell geometry provided an efficient charge carrier collection by shortening carrier transit times, which led to a superior photocurrent and gain. Thin metal shells around nanorods acted as a passivation layer to decrease surface states that cause prolonged carrier lifetimes and slow recovery of the photocurrent in nanorods. A combination of efficient carrier collection with surface passivation resulted in enhanced photocurrent and dynamic response at the same time in one device structure. In2S3 nanorod devices without the metal shell and with relatively thicker metal shell were also fabricated and characterized for comparison. In2S3 nanorods with thin metal shell showed the highest photosensitivity (photocurrent/dark current) response compared to two other designs. Microstructural, morphological, and electronic properties of the core/shell nanorods were used to explain the results observed.

  16. CdS/ZnS core-shell nanocrystal photosensitizers for visible to UV upconversion.

    Gray, Victor; Xia, Pan; Huang, Zhiyuan; Moses, Emily; Fast, Alexander; Fishman, Dmitry A; Vullev, Valentine I; Abrahamsson, Maria; Moth-Poulsen, Kasper; Lee Tang, Ming


    Herein we report the first example of nanocrystal (NC) sensitized triplet-triplet annihilation based photon upconversion from the visible to ultraviolet (vis-to-UV). Many photocatalyzed reactions, such as water splitting, require UV photons in order to function efficiently. Upconversion is one possible means of extending the usable range of photons into the visible. Vis-to-UV upconversion is achieved with CdS/ZnS core-shell NCs as the sensitizer and 2,5-diphenyloxazole (PPO) as annihilator and emitter. The ZnS shell was crucial in order to achieve any appreciable upconversion. From time resolved photoluminescence and transient absorption measurements we conclude that the ZnS shell affects the NC and triplet energy transfer (TET) from NC to PPO in two distinct ways. Upon ZnS growth the surface traps are passivated thus increasing the TET. The shell, however, also acts as a tunneling barrier for TET, reducing the efficiency. This leads to an optimal shell thickness where the upconversion quantum yield (Φ'UC) is maximized. Here the maximum Φ'UC was determined to be 5.2 ± 0.5% for 4 monolayers of ZnS shell on CdS NCs.

  17. Shell-Controlled Photoluminescence in CdSe/CNT Nanohybrids

    Si Hua-Yan


    Full Text Available Abstract A new type of nanohybrids containing carbon nanotubes (CNTs and CdSe quantum dots (QDs was prepared using an electrostatic self-assembly method. The CdSe QDs were capped by various mercaptocarboxylic acids, including thioglycolic acid (TGA, dihydrolipoic acid (DHLA and mercaptoundecanoic acid (MUA, which provide shell thicknesses of ~5.2, 10.6 and 15.2 Å, respectively. The surface-modified CdSe QDs are then self-assembled onto aridine orange-modified CNTs via electrostatic interaction to give CdSe/CNT nanohybrids. The photoluminescence (PL efficiencies of the obtained nanohybrids increase significantly with the increase of the shell thickness, which is attributed to a distance-dependent photo-induced charge-transfer mechanism. This work demonstrates a simple mean for fine tuning the PL properties of the CdSe/CNT nanohybrids and gains new insights to the photo-induced charge transfer in such nanostructures.

  18. Tuning upconversion through energy migration in core-shell nanoparticles

    Wang, Feng


    Photon upconversion is promising for applications such as biological imaging, data storage or solar cells. Here, we have investigated upconversion processes in a broad range of gadolinium-based nanoparticles of varying composition. We show that by rational design of a core-shell structure with a set of lanthanide ions incorporated into separated layers at precisely defined concentrations, efficient upconversion emission can be realized through gadolinium sublattice-mediated energy migration for a wide range of lanthanide activators without long-lived intermediary energy states. Furthermore, the use of the core-shell structure allows the elimination of deleterious cross-relaxation. This effect enables fine-tuning of upconversion emission through trapping of the migrating energy by the activators. Indeed, the findings described here suggest a general approach to constructing a new class of luminescent materials with tunable upconversion emissions by controlled manipulation of energy transfer within a nanoscopic region. © 2011 Macmillan Publishers Limited. All rights reserved.

  19. Mussel Shell Impaction in the Esophagus

    Sunmin Kim


    Full Text Available Mussels are commonly used in cooking around the world. The mussel shell breaks more easily than other shells, and the edge of the broken mussel shell is sharp. Impaction can ultimately cause erosion, perforation and fistula. Aside from these complications, the pain can be very intense. Therefore, it is essential to verify and remove the shell as soon as possible. In this report we describe the process of diagnosing and treating mussel shell impaction in the esophagus. Physicians can overlook this unusual foreign body impaction due to lack of experience. When physicians encounter a patient with severe chest pain after a meal with mussels, mussel shell impaction should be considered when diagnosing and treating the patient.

  20. Flow past a porous approximate spherical shell

    Srinivasacharya, D.


    In this paper, the creeping flow of an incompressible viscous liquid past a porous approximate spherical shell is considered. The flow in the free fluid region outside the shell and in the cavity region of the shell is governed by the Navier Stokes equation. The flow within the porous annulus region of the shell is governed by Darcy’s Law. The boundary conditions used at the interface are continuity of the normal velocity, continuity of the pressure and Beavers and Joseph slip condition. An exact solution for the problem is obtained. An expression for the drag on the porous approximate spherical shell is obtained. The drag experienced by the shell is evaluated numerically for several values of the parameters governing the flow.