WorldWideScience

Sample records for vm vl sol

  1. Congenital Cataract in Gpr161vl/vl Mice Is Modified by Proximal Chromosome 15

    Science.gov (United States)

    Li, Bo I.; Ababon, Myka R.; Matteson, Paul G.; Lin, Yong; Nanda, Vikas; Millonig, James H.

    2017-01-01

    The morphology and severity of human congenital cataract varies even among individuals with the same mutation, suggesting that genetic background modifies phenotypic penetrance. The spontaneous mouse mutant, vacuolated lens (vl), arose on the C3H/HeSnJ background. The mutation disrupts secondary lens fiber development by E16.5, leading to full penetrance of congenital cataract. The vl locus was mapped to a frameshift deletion in the orphan G protein-coupled receptor, Gpr161, which is expressed in differentiating lens fiber cells. When Gpr161vl/vl C3H mice are crossed to MOLF/EiJ mice an unexpected rescue of cataract is observed, suggesting that MOLF modifiers affect cataract penetrance. Subsequent QTL analysis mapped three modifiers (Modvl3-5: Modifier of vl) and in this study we characterized Modvl4 (Chr15; LOD = 4.4). A Modvl4MOLF congenic was generated and is sufficient to rescue congenital cataract and the lens fiber defect at E16.5. Additional phenotypic analysis on three subcongenic lines narrowed down the interval from 55 to 15Mb. In total only 18 protein-coding genes and 2 micro-RNAs are in this region. Fifteen of the 20 genes show detectable expression in the E16.5 eye. Subsequent expression studies in Gpr161vl/vl and subcongenic E16.5 eyes, bioinformatics analysis of C3H/MOLF polymorphisms, and the biological relevancy of the genes in the interval identified three genes (Cdh6, Ank and Trio) that likely contribute to the rescue of the lens phenotype. These studies demonstrate that modification of the Gpr161vl/vl cataract phenotype is likely due to genetic variants in at least one of three closely linked candidate genes on proximal Chr15. PMID:28135291

  2. Android Virtual Machine (VM) Setup on Linux

    Science.gov (United States)

    2014-12-01

    Machine (VM) Setup on Linux Ken F Yu Computational and Information Sciences Directorate, ARL...Virtual Machine (VM) Setup on Linux 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Ken F Yu 5d. PROJECT NUMBER

  3. Status and Roadmap of CernVM

    Science.gov (United States)

    Berzano, D.; Blomer, J.; Buncic, P.; Charalampidis, I.; Ganis, G.; Meusel, R.

    2015-12-01

    Cloud resources nowadays contribute an essential share of resources for computing in high-energy physics. Such resources can be either provided by private or public IaaS clouds (e.g. OpenStack, Amazon EC2, Google Compute Engine) or by volunteers computers (e.g. LHC@Home 2.0). In any case, experiments need to prepare a virtual machine image that provides the execution environment for the physics application at hand. The CernVM virtual machine since version 3 is a minimal and versatile virtual machine image capable of booting different operating systems. The virtual machine image is less than 20 megabyte in size. The actual operating system is delivered on demand by the CernVM File System. CernVM 3 has matured from a prototype to a production environment. It is used, for instance, to run LHC applications in the cloud, to tune event generators using a network of volunteer computers, and as a container for the historic Scientific Linux 5 and Scientific Linux 4 based software environments in the course of long-term data preservation efforts of the ALICE, CMS, and ALEPH experiments. We present experience and lessons learned from the use of CernVM at scale. We also provide an outlook on the upcoming developments. These developments include adding support for Scientific Linux 7, the use of container virtualization, such as provided by Docker, and the streamlining of virtual machine contextualization towards the cloud-init industry standard.

  4. Improved prediction of antibody VL-VH orientation.

    Science.gov (United States)

    Marze, Nicholas A; Lyskov, Sergey; Gray, Jeffrey J

    2016-10-01

    Antibodies are important immune molecules with high commercial value and therapeutic interest because of their ability to bind diverse antigens. Computational prediction of antibody structure can quickly reveal valuable information about the nature of these antigen-binding interactions, but only if the models are of sufficient quality. To achieve high model quality during complementarity-determining region (CDR) structural prediction, one must account for the VL-VH orientation. We developed a novel four-metric VL-VH orientation coordinate frame. Additionally, we extended the CDR grafting protocol in RosettaAntibody with a new method that diversifies VL-VH orientation by using 10 VL-VH orientation templates rather than a single one. We tested the multiple-template grafting protocol on two datasets of known antibody crystal structures. During the template-grafting phase, the new protocol improved the fraction of accurate VL-VH orientation predictions from only 26% (12/46) to 72% (33/46) of targets. After the full RosettaAntibody protocol, including CDR H3 remodeling and VL-VH re-orientation, the new protocol produced more candidate structures with accurate VL-VH orientation than the standard protocol in 43/46 targets (93%). The improved ability to predict VL-VH orientation will bolster predictions of other parts of the paratope, including the conformation of CDR H3, a grand challenge of antibody homology modeling.

  5. Creep Resistance of VM12 Steel

    OpenAIRE

    Zieliński A.; Golański G.; Dobrzański J.; Sroka M.

    2016-01-01

    This article presents selected material characteristics of VM12 steel used for elements of boilers with super- and ultra-critical steam parameters. In particular, abridged and long-term creep tests with and without elongation measurement during testing and investigations of microstructural changes due to long-term impact of temperature and stress were carried out. The practical aspect of the use of creep test results in forecasting the durability of materials operating under creep conditions ...

  6. Admission Control of VL in AFDX Under HRT Constraints

    Institute of Scientific and Technical Information of China (English)

    ZHOU Qiang; QU Zhenliang; LIN Hengqing

    2011-01-01

    Avionics full duplex switched ethernet (AFDX) is a switched interconnection technology developed to provide reliable data exchange with strong data transmission time guarantees in internal communication of the spacecraft or aircraft. Virtual link (VL) is an important concept of AFDX to meet quality of service (QoS) requirements in terms of end-to-end message deadlines. A VL admission control algorithm in AFDX network under hard real-time (HRT) constraints is studied. Based on the scheduling principle of AFDX protocol, a packet scheduling scheme under HRT constraints is proposed, and after that an efficient VL admission control algorithm is presented. Analytical proof that the algorithm can effectively determine whether VL should be admitted is given. Finally simulative examples are presented to promote the conclusion.

  7. Creep Resistance of VM12 Steel

    Directory of Open Access Journals (Sweden)

    Zieliński A.

    2016-09-01

    Full Text Available This article presents selected material characteristics of VM12 steel used for elements of boilers with super- and ultra-critical steam parameters. In particular, abridged and long-term creep tests with and without elongation measurement during testing and investigations of microstructural changes due to long-term impact of temperature and stress were carried out. The practical aspect of the use of creep test results in forecasting the durability of materials operating under creep conditions was presented. The characteristics of steels with regard to creep tests developed in this paper are used in assessment of changes in functional properties of the material of elements operating under creep conditions.

  8. ABangle: characterising the VH-VL orientation in antibodies.

    Science.gov (United States)

    Dunbar, J; Fuchs, A; Shi, J; Deane, C M

    2013-10-01

    The binding site of an antibody is formed between the two variable domains, VH and VL, of its antigen binding fragment (Fab). Understanding how VH and VL orientate with respect to one another is important both for studying the mechanisms of antigen specificity and affinity and improving antibody modelling, docking and engineering. Different VH-VL orientations are commonly described using relative measures such as root-mean-square deviation. Recently, the orientation has also been characterised using the absolute measure of a VH-VL packing angle. However, a single angle cannot fully describe all modes of orientation. Here, we present a method which fully characterises VH-VL orientation in a consistent and absolute sense using five angles (HL, HC1, LC1, HC2 and LC2) and a distance (dc). Additionally, we provide a computational tool, ABangle, to allow the VH-VL orientation for any antibody to be automatically calculated and compared with all other known structures. We compare previous studies and show how the modes of orientation being identified relate to movements of different angles. Thus, we are able to explain why different studies identify different structural clusters and different residues as important. Given this result, we then identify those positions and their residue identities which influence each of the angular measures of orientation. Finally, by analysing VH-VL orientation in bound and unbound forms, we find that antibodies specific for protein antigens are significantly more flexible in their unbound form than antibodies specific for hapten antigens. ABangle is freely available at http://opig.stats.ox.ac.uk/webapps/abangle.

  9. Secure VM for Monitoring Industrial Process Controllers

    Energy Technology Data Exchange (ETDEWEB)

    Dasgupta, Dipankar [ORNL; Ali, Mohammad Hassan [University of Memphis; Abercrombie, Robert K [ORNL; Schlicher, Bob G [ORNL; Sheldon, Frederick T [ORNL; Carvalho, Marco [Institute of Human and Machine Cognition

    2011-01-01

    In this paper, we examine the biological immune system as an autonomic system for self-protection, which has evolved over millions of years probably through extensive redesigning, testing, tuning and optimization process. The powerful information processing capabilities of the immune system, such as feature extraction, pattern recognition, learning, memory, and its distributive nature provide rich metaphors for its artificial counterpart. Our study focuses on building an autonomic defense system, using some immunological metaphors for information gathering, analyzing, decision making and launching threat and attack responses. In order to detection Stuxnet like malware, we propose to include a secure VM (or dedicated host) to the SCADA Network to monitor behavior and all software updates. This on-going research effort is not to mimic the nature but to explore and learn valuable lessons useful for self-adaptive cyber defense systems.

  10. THE DYNAMICS AND TRACTION ENERGY METRICS LOCOMOTIVE VL40

    Directory of Open Access Journals (Sweden)

    S. V. Pylypenko

    2008-03-01

    Full Text Available In the article the results of dynamic running and traction-energy tests of the electric locomotive VL40U are presented. In accordance with the test results a conclusion about the suitability of electric locomotive of such a type for operation with trains containing up to 15 passenger coaches inclusive is made.

  11. Moving to a total VM environment

    Energy Technology Data Exchange (ETDEWEB)

    Johnston, T.Y.

    1981-08-11

    The Stanford Linear Accelerator Center is a single purpose laboratory operated by Stanford University for the Department of Energy. Its mission is to do research in High Energy (particle) physics. This research involves the use of large and complex electronic detectors. Each of these detectors is a multi-million dollar device. A part of each detector is a computer for process control and data logging. Most detectors at SLAC now use VAX 11/780s for this purpose. Most detectors record digital data via this process control computer. Consequently, physics today is not bounded by the cost of analog to digital conversion as it was in the past, and the physicist is able to run larger experiments than were feasible a decade ago. Today a medium sized experiment will produce several hundred full reels of 6250 BPI tape whereas a large experiment is a couple of thousand reels. The raw data must first be transformed into physics events using data transformation programs. The physicists then use subsets of the data to understand what went on. The subset may be anywhere from a few megabytes to 5 or 6 gigabytes of data (30 or 40 full reels of tape). This searching would be best solved interactively (if computers and I/0 devices were fast enough). Instead what we find are very dynamic batch programs that are generally changed every run. The result is that on any day there are probably around 50 to 100 physicists interacting with a half dozen different experiments who are causing us to mount around 750 to 1000 tapes a day. This has been the style of computing for the last decade. Our going to VM is part of our effort to change this style of computing and to make physics computing more effective.

  12. Enabling μCernVM for the Interactive Use Case

    CERN Document Server

    Nicolaou, Vasilis

    2013-01-01

    The $\\mu$CernVM will be the successor of the CernVM as a new appliance to help with accessing LHC for data analysis and development. CernVM has a web appliance agent that facilitates user interaction with the virtual machine and reduces the need for executing shell commands or installing graphical applications for displaying basic information such as memory usage or performing simple tasks such as updating the operating system. The updates are done differently in the $\\mu$CernVM than mainstream Linux distributions. Its filesystem is a composition of a read-only layer that exists in the network and a read/write layer that is initilised on first boot and keeps the user changes afterwards. Thus, means are provided to avoid loss of user data and system instabilities when the operating system is updated by fetching a new read-only layer.

  13. CernVM: Minimal maintenance approach to virtualization

    Science.gov (United States)

    Buncic, Predrag; Aguado-Sanchez, Carlos; Blomer, Jakob; Harutyunyan, Artem

    2011-12-01

    CernVM is a virtual software appliance designed to support the development cycle and provide a runtime environment for the LHC experiments. It consists of three key components that differentiate it from more traditional virtual machines: a minimal Linux Operating System (OS), a specially tuned file system designed to deliver application software on demand, and contextualization tools that provide a means to easily customize and configure CernVM instances for different tasks and user communities. In this contribution we briefly describe the most important use cases for virtualization in High Energy Physics (HEP), CernVM key components and discuss how end-to-end systems corresponding to these use cases can be realized using CernVM.

  14. Workload-aware VM Scheduling on Multicore Systems

    Directory of Open Access Journals (Sweden)

    Insoon Jo

    2011-11-01

    Full Text Available In virtualized environments, performance interference between virtual machines (VMs is a key challenge. In order to mitigate resource contention, an efficient VM scheduling is positively necessary.In this paper, we propose a workload-aware VM scheduler on multi-core systems, which finds a systemwide mapping of VMs to physical cores. Our work aims not only at minimizing the number of used hosts,but at maximizing the system throughput. To achieve the first goal, our scheduler dynamically adjusts a set of used hosts. To achieve the second goal, it maps each VM on a physical core where the physical core and its host most sufficiently meet the resource requirements of the VM. Evaluation demonstrates that our scheduling ensures efficient use of data center resources.

  15. Savannah River VM--Intellect application support documentation

    Energy Technology Data Exchange (ETDEWEB)

    Carter, L.S.

    1988-09-23

    This document details the underlying support programming and structures that support the INTELLECT and KBMS products at the Savannah River Facility. The target audience for this document includes INTELLECT System Administrators, INTELLECT programmers and developers, and VM Systems Programmers.

  16. Porting of $\\mu$CernVM to AArch64

    CERN Document Server

    Scheffler, Felix

    2016-01-01

    $\\mu$CernVM is a virtual appliance that contains a stripped-down Linux OS connecting to a CernVM-Filesystem (CVMFS) repository that resides on a dedicated web server. In contrast to “usual” VMs, anything that is needed from this repository is only downloaded on demand, aggressively cached and eventually released again. Currently, $\\mu$CernVM is only distributed for x86-64. Recently, ARM (market leader in mobile computing) has started to enter the server market, which is still dominated by x86-64 infrastructure. However, in terms of performance/watt, AArch64 (latest ARM 64bit architecture) is a promising alternative. Facing millions of jobs to compute every day, it is thus desirable to have an HEP virtualisation solution for AArch64. In this project, $\\mu$CernVM was successfully ported to AArch64. Native and virtualised runtime performance was evaluated using ROOT6 and CMS benchmarks. It was found that VM performance is inferior to host performance across all tests. Respective numbers greatly vary between...

  17. Expedition sol

    DEFF Research Database (Denmark)

    Jacobsen, Aase Roland

    2006-01-01

    Tag på expedition sol rundt i museet. Er der nogen, der har taget en bid af solen? Hvorfor bliver der solformørkelse? Kan vi undvære Solen?......Tag på expedition sol rundt i museet. Er der nogen, der har taget en bid af solen? Hvorfor bliver der solformørkelse? Kan vi undvære Solen?...

  18. Optimization of CernVM early boot process

    CERN Document Server

    Mazdin, Petra

    2015-01-01

    CernVM virtual machine is a Linux based virtual appliance optimized for High Energy Physics experiments. It is used for cloud computing, volunteer computing, and software development by the four large LHC experiments. The goal of this project is proling and optimizing the boot process of the CernVM. A key part was the development of a performance profiler for shell scripts as an extension to the popular BusyBox open source UNIX tool suite. Based on the measurements, costly shell code was replaced by more efficient, custom C programs. The results are compared to the original ones and successful optimization is proven.

  19. Analysis and prediction of VH/VL packing in antibodies.

    Science.gov (United States)

    Abhinandan, K R; Martin, Andrew C R

    2010-09-01

    The packing of V(H) and V(L) domains in antibodies can vary, influencing the topography of the antigen-combining site. However, until recently, this has largely been ignored in modelling antibody structure. We present an analysis of the degree of variability observed in known structures together with a machine-learning approach to predict the packing angle. A neural network was trained on sets of interface residues and a genetic algorithm designed to perform 'feature selection' to define which sets of interface residues could be used most successfully to perform the prediction. While this training procedure was very computationally intensive, prediction is performed in a matter of seconds. Thus, not only do we provide a rapid method for predicting the packing angle, but also we define a set of residues that may be important in antibody humanization in order to obtain the correct binding site topography.

  20. Prediction of VH-VL domain orientation for antibody variable domain modeling.

    Science.gov (United States)

    Bujotzek, Alexander; Dunbar, James; Lipsmeier, Florian; Schäfer, Wolfgang; Antes, Iris; Deane, Charlotte M; Georges, Guy

    2015-04-01

    The antigen-binding site of antibodies forms at the interface of their two variable domains, VH and VL, making VH-VL domain orientation a factor that codetermines antibody specificity and affinity. Preserving VH-VL domain orientation in the process of antibody engineering is important in order to retain the original antibody properties, and predicting the correct VH-VL orientation has also been recognized as an important factor in antibody homology modeling. In this article, we present a fast sequence-based predictor that predicts VH-VL domain orientation with Q(2) values ranging from 0.54 to 0.73 on the evaluation set. We describe VH-VL orientation in terms of the six absolute ABangle parameters that have recently been proposed as a means to separate the different degrees of freedom of VH-VL domain orientation. In order to assess the impact of adjusting VH-VL orientation according to our predictions, we use the set of antibody structures of the recently published Antibody Modeling Assessment (AMA) II study. In comparison to the original AMAII homology models, we find an improvement in the accuracy of VH-VL orientation modeling, which also translates into an improvement in the average root-mean-square deviation with regard to the crystal structures.

  1. PEMILIHAN DAN MIGRASI VM MENGGUNAKAN MCDM UNTUK PENINGKATAN KINERJA LAYANAN PADA CLOUD COMPUTING

    Directory of Open Access Journals (Sweden)

    Abdullah Fadil

    2016-08-01

    Full Text Available Komputasi awan atau cloud computing merupakan lingkungan yang heterogen dan terdistribusi, tersusun atas gugusan jaringan server dengan berbagai kapasitas sumber daya komputasi yang berbeda-beda guna menopang model layanan yang ada di atasnya. Virtual machine (VM dijadikan sebagai representasi dari ketersediaan sumber daya komputasi dinamis yang dapat dialokasikan dan direalokasikan sesuai dengan permintaan. Mekanisme live migration VM di antara server fisik yang terdapat di dalam data center cloud digunakan untuk mencapai konsolidasi dan memaksimalkan utilisasi VM. Pada prosedur konsoidasi vm, pemilihan dan penempatan VM sering kali menggunakan kriteria tunggal dan statis. Dalam penelitian ini diusulkan pemilihan dan penempatan VM menggunakan multi-criteria decision making (MCDM pada prosedur konsolidasi VM dinamis di lingkungan cloud data center guna meningkatkan layanan cloud computing. Pendekatan praktis digunakan dalam mengembangkan lingkungan cloud computing berbasis OpenStack Cloud dengan mengintegrasikan VM selection dan VM Placement pada prosedur konsolidasi VM menggunakan OpenStack-Neat. Hasil penelitian menunjukkan bahwa metode pemilihan dan penempatan VM melalui live migration mampu menggantikan kerugian yang disebabkan oleh down-times sebesar 11,994 detik dari waktu responnya. Peningkatan response times terjadi sebesar 6 ms ketika terjadi proses live migration VM dari host asal ke host tujuan. Response times rata-rata setiap vm yang tersebar pada compute node setelah terjadi proses live migration sebesar 67 ms yang menunjukkan keseimbangan beban pada sistem cloud computing.

  2. Experimental results on V-M type pulse tube refrigerator

    Science.gov (United States)

    Dai, Wei; Matsubara, Yoichi; Kobayashi, Hisayasu

    2002-06-01

    This article mainly introduces experimental results on a new type pulse tube refrigerator named as V-M type pulse tube refrigerator. The main difference from Stirling type or G-M type pulse tube refrigerator is that thermal compressor similar to that of a V-M cryocooler is used instead of mechanical compressor. By using temperature difference between room temperature and liquid nitrogen, pressure wave with high to low pressure ratio around 1.2 is obtained. This pressure wave is used to generate cooling effect at the cold end. With a 20 K pre-cooler, this machine reaches lowest temperature 5.25 K by using helium 4 at 0.77 Hz, 19 bar charge pressure. DC flow plays an important role in our system. It not only influences the final obtainable lowest temperature, but also is used to increase cold end cool-down speed. Total volume of the V-M type pulse tube refrigerator is around 3.3 l. However, dead volume inside rotor housing occupies about 2.8 l and can be much reduced.

  3. Data of evolutionary structure change: 1VL8A-2UVDD [Confc[Archive

    Lifescience Database Archive (English)

    Full Text Available 1VL8A-2UVDD 1VL8 2UVD A D FDLRGRVALVTGGSRGLGFGIAQGLAEAGCSVVVASRN-...ne>ALA CA 330 SER CA 279 2UVD D 2UVDD VNYAGNEQKAN EEE H...0431976318 2.622323989868164 1 2UV...D D 2UVDD EIKKL-GSDA

  4. Data of evolutionary structure change: 1VL8B-2UVDB [Confc[Archive

    Lifescience Database Archive (English)

    Full Text Available 1VL8B-2UVDB 1VL8 2UVD B B VFDLRGRVALVTGGSRGLGFGIAQGLAEAGCSVVVASRN...>GLU CA 241 ALA CA 324 SER CA 282 2UV...D B 2UVDB VNYAGNEQKAN 2.647510051727295 1 2UV...D B 2UVDB EIKKL-GSDAI

  5. EFFICIENT VM LOAD BALANCING ALGORITHM FOR A CLOUD COMPUTING ENVIRONMENT

    Directory of Open Access Journals (Sweden)

    Jasmin James

    2012-09-01

    Full Text Available Cloud computing is a fast growing area in computing research and industry today. With the advancement of the Cloud, there are new possibilities opening up on how applications can be built and how different services can be offered to the end user through Virtualization, on the internet. There are the cloud service providers who provide large scaled computing infrastructure defined on usage, and provide the infrastructure services in a very flexiblemanner which the users can scale up or down at will. The establishment of an effective load balancing algorithm and how to use Cloud computing resources efficiently for effective and efficient cloud computing is one of the Cloud computing service providers’ultimate goals. In this paper firstly analysis of different Virtual Machine (VM load balancing algorithms is done. Secondly, a new VM load balancing algorithm has been proposed and implemented for an IaaS framework in Simulated cloud computing environment; i.e. ‘Weighted Active Monitoring Load Balancing Algorithm’ using CloudSimtools, for the Datacenter to effectively load balance requests between the available virtual machines assigning a weight, in order to achieve better performance parameters such as response time and Data processing time.

  6. Toxicity and medical countermeasure studies on the organophosphorus nerve agents VM and VX.

    Science.gov (United States)

    Rice, Helen; Dalton, Christopher H; Price, Matthew E; Graham, Stuart J; Green, A Christopher; Jenner, John; Groombridge, Helen J; Timperley, Christopher M

    2015-04-08

    To support the effort to eliminate the Syrian Arab Republic chemical weapons stockpile safely, there was a requirement to provide scientific advice based on experimentally derived information on both toxicity and medical countermeasures (MedCM) in the event of exposure to VM, VX or VM-VX mixtures. Complementary in vitro and in vivo studies were undertaken to inform that advice. The penetration rate of neat VM was not significantly different from that of neat VX, through either guinea pig or pig skin in vitro. The presence of VX did not affect the penetration rate of VM in mixtures of various proportions. A lethal dose of VM was approximately twice that of VX in guinea pigs poisoned via the percutaneous route. There was no interaction in mixed agent solutions which altered the in vivo toxicity of the agents. Percutaneous poisoning by VM responded to treatment with standard MedCM, although complete protection was not achieved.

  7. Experience on QA in the CernVM File System

    CERN Document Server

    CERN. Geneva; MEUSEL, Rene

    2015-01-01

    The CernVM-File System (CVMFS) delivers experiment software installations to thousands of globally distributed nodes in the WLCG and beyond. In recent years it became a mission-critical component for offline data processing of the LHC experiments and many other collaborations. From a software engineering perspective, CVMFS is a medium-sized C++ system-level project. Following the growth of the project, we introduced a number of measures to improve the code quality, testability, and maintainability. In particular, we found very useful code reviews through github pull requests and automated unit- and integration testing. We are also transitioning to a test-driven development for new features and bug fixes. These processes are supported by a number of tools, such as Google Test, Jenkins, Docker, and others. We would like to share our experience on problems we encountered and on which processes and tools worked well for us.

  8. Performance Tests of CMSSW on the CernVM

    Science.gov (United States)

    Petek, Marko; Gowdy, Stephen

    2012-12-01

    The CERN Virtual Machine (CernVM) Software Appliance is a project developed in CERN with the goal of allowing the execution of the experiment's software on different operating systems in an easy way for the users. To achieve this it makes use of Virtual Machine images consisting of a JEOS (Just Enough Operating System) Linux image, bundled with CVMFS, a distributed file system for software. This image can then be run with a proper virtualizer on most of the platforms available. It also aggressively caches data on the local user's machine so that it can operate disconnected from the network. CMS wanted to compare the performance of the CMS Software running in the virtualized environment with the same software running on a native Linux box. To answer this wish, a series of tests were made on a controlled environment during 2010-2011. This work presents the results of those tests.

  9. 3-D-eChem VM: Cheminformatics Research Infrastructure in a Downloadable Virtual Machine

    OpenAIRE

    Verhoeven, Stefan; Vass, Marton; de Esch, Iwan; Leurs, Rob; Lusher, Scott; Vriend, Gerrrit; Ritschel, Tina; de Graaf, Chris; McGuire, Ross

    2016-01-01

    3D-e-Chem VM is a freely available Virtual Machine (VM) encompassing tools, databases & workflows, including new resources developed for ligand binding site comparisons and GPCR research. The VM contains a fully functional cheminformatics infrastructure consisting of a chemistry enabled relational database system (PostgreSQL + RDKit) with a data analytics workflow tool (KNIME) and additional cheminformatics capabilities. Tools, workflows and reference data sets are made available. The wid...

  10. Investigating the role of the ventromedial prefrontal cortex (vmPFC in the assessment of brands

    Directory of Open Access Journals (Sweden)

    Jose Paulo eSantos

    2011-06-01

    Full Text Available The ventromedial prefrontal cortex (vmPFC is believed to be important in everyday preference judgments, processing emotions during decision-making. However, there is still controversy in the literature regarding the participation of the vmPFC. To further elucidate the contribution of the vmPFC in brand preference, we designed a functional magnetic resonance imaging (fMRI study where 18 subjects assessed positive, indifferent and fictitious brands. Also, both the period during and after the decision process were analyzed, hoping to unravel temporally the role of the vmPFC, using modeled and model-free fMRI analysis. Considering together the period before and after decision-making, there was activation of the vmPFC when comparing positive with indifferent or fictitious brands. However, when the decision-making period was separated from the moment after the response, and especially for positive brands, the vmPFC was more active after the choice than during the decision process itself, challenging some of the existing literature. The results of the present study support the notion that the vmPFC may be unimportant in the decision stage of brand preference, questioning theories that postulate that the vmPFC is in the origin of such a choice. Further studies are needed to investigate in detail why the vmPFC seems to be involved in brand preference only after the decision process.

  11. Antibody VH and VL recombination using phage and ribosome display technologies reveals distinct structural routes to affinity improvements with VH-VL interface residues providing important structural diversity.

    Science.gov (United States)

    Groves, Maria A T; Amanuel, Lily; Campbell, Jamie I; Rees, D Gareth; Sridharan, Sudharsan; Finch, Donna K; Lowe, David C; Vaughan, Tristan J

    2014-01-01

    In vitro selection technologies are an important means of affinity maturing antibodies to generate the optimal therapeutic profile for a particular disease target. Here, we describe the isolation of a parent antibody, KENB061 using phage display and solution phase selections with soluble biotinylated human IL-1R1. KENB061 was affinity matured using phage display and targeted mutagenesis of VH and VL CDR3 using NNS randomization. Affinity matured VHCDR3 and VLCDR3 library blocks were recombined and selected using phage and ribosome display protocol. A direct comparison of the phage and ribosome display antibodies generated was made to determine their functional characteristics.In our analyses, we observed distinct differences in the pattern of beneficial mutations in antibodies derived from phage and ribosome display selections, and discovered the lead antibody Jedi067 had a ~3700-fold improvement in KD over the parent KENB061. We constructed a homology model of the Fv region of Jedi067 to map the specific positions where mutations occurred in the CDR3 loops. For VL CDR3, positions 94 to 97 carry greater diversity in the ribosome display variants compared with the phage display. The positions 95a, 95b and 96 of VLCDR3 form part of the interface with VH in this model. The model shows that positions 96, 98, 100e, 100f, 100 g, 100h, 100i and 101 of the VHCDR3 include residues at the VH and VL interface. Importantly, Leu96 and Tyr98 are conserved at the interface positions in both phage and ribosome display indicating their importance in maintaining the VH-VL interface. For antibodies derived from ribosome display, there is significant diversity at residues 100a to 100f of the VH CDR3 compared with phage display. A unique deletion of isoleucine at position 102 of the lead candidate, Jedi067, also occurs in the VHCDR3.As anticipated, recombining the mutations via ribosome display led to a greater structural diversity, particularly in the heavy chain CDR3, which in turn

  12. Vlček Seminars” About the System Approaches at CTU in Prague

    Directory of Open Access Journals (Sweden)

    Veronika Vlčková

    2016-12-01

    Full Text Available In the academic year 2015-2016 at CTU in Prague, Faculty of Transportation Sciences carried out in a more traditional "Vlček seminars", which take place intermittently since 1999. The purpose of the seminars is to look for new, innovative impulses, systems approach to problem solving, organize knowledges and insights on systems engineering tools and objectives and possible areas of their application. The methodological basis is constructive theory of systems, presented by prof. Jaroslav Vlček.

  13. Isolated T Wave Inversion in Lead aVL: An ECG Survey and a Case Report

    Directory of Open Access Journals (Sweden)

    Getaw Worku Hassen

    2015-01-01

    Full Text Available Background. Computerized electrocardiogram (ECG analysis has been of tremendous help for noncardiologists, but can we rely on it? The importance of ST depression and T wave inversions in lead aVL has not been emphasized and not well recognized across all specialties. Objective. This study’s goal was to analyze if there is a discrepancy of interpretation by physicians from different specialties and a computer-generated ECG reading in regard to a TWI in lead aVL. Methods. In this multidisciplinary prospective study, a single ECG with isolated TWI in lead aVL that was interpreted by the computer as normal was given to all participants to interpret in writing. The readings by all physicians were compared by level of education and by specialty to one another and to the computer interpretation. Results. A total of 191 physicians participated in the study. Of the 191 physicians 48 (25.1% identified and 143 (74.9% did not identify the isolated TWI in lead aVL. Conclusion. Our study demonstrated that 74.9% did not recognize the abnormality. New and subtle ECG findings should be emphasized in their training so as not to miss significant findings that could cause morbidity and mortality.

  14. Estimation of under-reported visceral Leishmaniasis (Vl cases in Bihar: a Bayesian approach

    Directory of Open Access Journals (Sweden)

    A Ranjan

    2013-12-01

    Full Text Available Background: Visceral leishmaniasis (VL is a major health problem in the state of Bihar and adjoining areas in India. In absence of any active surveillance mechanism for the disease, there seems to be gross under-reporting of VL cases. Objective: The objective of this study was to estimate extent of under-reporting of VL cases in Bihar using pooled analysis of published papers. Method: We calculated the pooled common ratio (RRMH based on three studies and combined it with a prior distribution of ratio using inverse-variance weighting method. Bayesian method was used to estimate the posterior distribution of the “under-reporting factor” (ratio of unreported to reported cases. Results: The posterior distribution of ratio of unreported to reported cases yielded a mean of 3.558, with 95% posterior limits of 2.81 and 4.50. Conclusion: Bayesian approach gives evidence to the fact that the total number of VL cases in the state may be nearly more than three times that of currently reported figures. 

  15. VL51ES (Generation 6 Li-Ion Cell for Satellites

    Directory of Open Access Journals (Sweden)

    Defer M.

    2017-01-01

    Full Text Available This paper presents the design of Saft’s VL51ES (Generation 6 Li-Ion cell, the main challenges in the course of the development, the main BOL characteristics and performances achieved during the development program. Finally, it also describes how this cell fits in Saft’s battery range and the benefits of it.

  16. Toxicity and medical countermeasure studies on the organophosphorus nerve agents VM and VX

    OpenAIRE

    Rice, Helen; Dalton, Christopher H.; Price, Matthew E.; Stuart J Graham; Green, A. Christopher; Jenner, John; Groombridge, Helen J.; Timperley, Christopher M.

    2015-01-01

    To support the effort to eliminate the Syrian Arab Republic chemical weapons stockpile safely, there was a requirement to provide scientific advice based on experimentally derived information on both toxicity and medical countermeasures (MedCM) in the event of exposure to VM, VX or VM–VX mixtures. Complementary in vitro and in vivo studies were undertaken to inform that advice. The penetration rate of neat VM was not significantly different from that of neat VX, through either guinea pig or p...

  17. Tau Leptonic Decay τ→lVlVτ in Littlest Higgs Model*

    Institute of Scientific and Technical Information of China (English)

    YUEChong-Xing; WANGWei

    2004-01-01

    We consider the T leptonic decay τ→lVlVτ in the framework of the littlest Higgs (LH) model and calculate the corrections of new particles to this decay. We find that the contributions of the charged scalars can be safely ignored and the LH model is in perfect agreement with the universality of the couplings of the SU gauge bosons to the leptonic charged currents. The corrections of the LH model to the T leptonic decay τ→lVlVτ are not sensitive to the parameter c, but depend strongly on the parameters f and x. The precision measured data about the T leptonic decay demand that the parameter f approximately equal 3.5 TeV and x > 0.1, while agree with the general expectation based on other phenomenological explorations.

  18. Effectiveness Study of Paromomycin IM Injection (PMIM for the Treatment of Visceral Leishmaniasis (VL in Bangladesh.

    Directory of Open Access Journals (Sweden)

    Kazi M Jamil

    Full Text Available This study was conducted in Bangladeshi patients in an outpatient setting to support registration of Paromomycin Intramuscular Injection (PMIM as a low-cost treatment option in Bangladesh.This Phase IIIb, open-label, multi-center, single-arm trial assessed the efficacy and safety of PMIM administered at 11 mg/kg (paromomycin base intramuscularly once daily for 21 consecutive days to children and adults with VL in a rural outpatient setting in Bangladesh. Patients ≥5 and ≤55 years were eligible if they had signs and symptoms of VL (intermittent fever, weight loss/decreased appetite, and enlarged spleen, positive rK39 test, and were living in VL-endemic areas. Compliance was the percentage of enrolled patients who received 21 daily injections over no more than 22 days. Efficacy was evaluated by initial clinical response, defined as resolution of fever and reduction of splenomegaly at end of treatment, and final clinical response, defined as the absence of new clinical signs and symptoms of VL 6 months after end of treatment. Safety was assessed by evaluation of adverse events.A total of 120 subjects (49% pediatric were enrolled. Treatment compliance was 98.3%. Initial clinical response in the Intent-to-Treat population was 98.3%, and final clinical response 6 months after end of treatment was 94.2%. Of the 119 subjects who received ≥1 dose of PMIM, 28.6% reported at least one adverse event. Injection site pain was the most commonly reported adverse event. Reversible renal impairment and/or hearing loss were reported in 2 subjects.PMIM was an effective and safe treatment for VL in Bangladesh. The short treatment duration and lower cost of PMIM compared with other treatment options may make this drug a preferred treatment to be investigated as part of a combination therapy regimen. This study supports the registration of PMIM for use in government health facilities in Bangladesh.ClinicalTrials.gov identifier: NCT01328457.

  19. SolNet

    DEFF Research Database (Denmark)

    Jordan, Ulrike; Vajen, Klaus; Bales, Chris;

    2014-01-01

    SolNet, founded in 2006, is the first coordinated International PhD education program on Solar Thermal Engineering. The SolNet network is coordinated by the Institute of Thermal Engineering at Kassel University, Germany. The network offers PhD courses on solar heating and cooling, conference...

  20. Properties and Microstructure of Laser Welded VM12-SHC Steel Pipes Joints

    Directory of Open Access Journals (Sweden)

    Skrzypczyk A.

    2016-06-01

    Full Text Available Paper presents results of microstructure and tests of welded joints of new generation VM12-SHC martensitic steel using high power CO2 laser (LBW method with bifocal welding head. VM12-SHC is dedicated to energetic installation material, designed to replace currently used. High content of chromium and others alloying elements improve its resistance and strength characteristic. Use of VM12-SHC steel for production of the superheaters, heating chambers and walls in steam boilers resulted in various weldability researches. In article are presented results of destructive and non-destructive tests. For destructive: static bending and Vickers hardness tests, and for non-destructive: VT, RT, UT, micro and macroscopic tests were performed.

  1. Correlation of VEGF and COX-2 Expression with VM in Malignant Melanomas

    Institute of Scientific and Technical Information of China (English)

    BaocunSun; ShiwuZhang; XiulanZhao; YanxueLiu; ChunshengNi; DanfangZhang; HongQi; ZhiyongLiu; XishanHao

    2004-01-01

    OBJECTIVE To investigate the relationship between vascular epithelial growth factor (VEGF) and cyclooxygenase-2 (COX-2) in melanomas and the expressive difference of VEGF and COX-2 between melanomas with and without vasculogenic mimicry(VM).METHODS Sixty cases of malignant melanomas emoeaaea In paraffin were studied. The tumors were divided into a high-grade malignant group and a low-grade malignant group based on their tumor type, atypia and survival time of the patient. Then tissue microarrays were produced from these paraffin-embedded tumor tissues which were stained for VEGF, COX-2 and PAS. The difference in expression between VEGF and COX-2 in the malignant melanomas was compared using a grid-count. In addition, the tumors were also divided into mimicry and non-mimicry groups based on their PAS staining. Then the differences between the PAS positive and negative areas of the 2 groups were compared.RESULTS In malignant melanomas with VM, VEGF and COX-2 expression was less in tumors in which VM was absent, but VEGF, COX-2 expression in high-grade malignant melanomas was higher than that in low-grade grade malignant melanomas. Expression of VEGF was correlated with COX-2 expression.CONCLUSION VM exists in some high-grade malignant melanomas. The differences and relations between VEGF and COX-2 showed that some high-grade malignant melanomas possess a unique molecular-mechanism of tumor metastasis and blood supply.

  2. HotpathVM: An Effective JIT for Resource-constrained Devices

    DEFF Research Database (Denmark)

    Gal, Andreas; Franz, Michael; Probst, Christian

    2006-01-01

    We present a just-in-time compiler for a Java VM that is small enough to fit on resource-constrained devices, yet surprisingly effective. Our system dynamically identifies traces of frequently executed bytecode instructions (which may span several basic blocks across several methods) and compiles...... benchmarks show a speedup that in some cases rivals heavy-weight just-in-time compilers....

  3. 3D-e-Chem-VM: Structural Cheminformatics Research Infrastructure in a Freely Available Virtual Machine.

    Science.gov (United States)

    McGuire, Ross; Verhoeven, Stefan; Vass, Márton; Vriend, Gerrit; de Esch, Iwan J P; Lusher, Scott J; Leurs, Rob; Ridder, Lars; Kooistra, Albert J; Ritschel, Tina; de Graaf, Chris

    2017-02-14

    3D-e-Chem-VM is an open source, freely available Virtual Machine ( http://3d-e-chem.github.io/3D-e-Chem-VM/ ) that integrates cheminformatics and bioinformatics tools for the analysis of protein-ligand interaction data. 3D-e-Chem-VM consists of software libraries, and database and workflow tools that can analyze and combine small molecule and protein structural information in a graphical programming environment. New chemical and biological data analytics tools and workflows have been developed for the efficient exploitation of structural and pharmacological protein-ligand interaction data from proteomewide databases (e.g., ChEMBLdb and PDB), as well as customized information systems focused on, e.g., G protein-coupled receptors (GPCRdb) and protein kinases (KLIFS). The integrated structural cheminformatics research infrastructure compiled in the 3D-e-Chem-VM enables the design of new approaches in virtual ligand screening (Chemdb4VS), ligand-based metabolism prediction (SyGMa), and structure-based protein binding site comparison and bioisosteric replacement for ligand design (KRIPOdb).

  4. Overhead-Aware-Best-Fit (OABF) Resource Allocation Algorithm for Minimizing VM Launching Overhead

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Hao [IIT; Garzoglio, Gabriele [Fermilab; Ren, Shangping [IIT, Chicago; Timm, Steven [Fermilab; Noh, Seo Young [KISTI, Daejeon

    2014-11-11

    FermiCloud is a private cloud developed in Fermi National Accelerator Laboratory to provide elastic and on-demand resources for different scientific research experiments. The design goal of the FermiCloud is to automatically allocate resources for different scientific applications so that the QoS required by these applications is met and the operational cost of the FermiCloud is minimized. Our earlier research shows that VM launching overhead has large variations. If such variations are not taken into consideration when making resource allocation decisions, it may lead to poor performance and resource waste. In this paper, we show how we may use an VM launching overhead reference model to minimize VM launching overhead. In particular, we first present a training algorithm that automatically tunes a given refer- ence model to accurately reflect FermiCloud environment. Based on the tuned reference model for virtual machine launching overhead, we develop an overhead-aware-best-fit resource allocation algorithm that decides where and when to allocate resources so that the average virtual machine launching overhead is minimized. The experimental results indicate that the developed overhead-aware-best-fit resource allocation algorithm can significantly improved the VM launching time when large number of VMs are simultaneously launched.

  5. 3D-e-Chem-VM: Structural Cheminformatics Research Infrastructure in a Freely Available Virtual Machine

    Science.gov (United States)

    2017-01-01

    3D-e-Chem-VM is an open source, freely available Virtual Machine (http://3d-e-chem.github.io/3D-e-Chem-VM/) that integrates cheminformatics and bioinformatics tools for the analysis of protein–ligand interaction data. 3D-e-Chem-VM consists of software libraries, and database and workflow tools that can analyze and combine small molecule and protein structural information in a graphical programming environment. New chemical and biological data analytics tools and workflows have been developed for the efficient exploitation of structural and pharmacological protein–ligand interaction data from proteomewide databases (e.g., ChEMBLdb and PDB), as well as customized information systems focused on, e.g., G protein-coupled receptors (GPCRdb) and protein kinases (KLIFS). The integrated structural cheminformatics research infrastructure compiled in the 3D-e-Chem-VM enables the design of new approaches in virtual ligand screening (Chemdb4VS), ligand-based metabolism prediction (SyGMa), and structure-based protein binding site comparison and bioisosteric replacement for ligand design (KRIPOdb). PMID:28125221

  6. A Study on L-Asparaginase of Nocardia levis MK-VL_113

    Directory of Open Access Journals (Sweden)

    Alapati Kavitha

    2012-01-01

    Full Text Available An enzyme-based drug, L-asparaginase, was produced by Nocardia levis MK-VL_113 isolated from laterite soils of Guntur region. Cultural parameters affecting the production of L-asparaginase by the strain were optimized. Maximal yields of L-asparaginase were recorded from 3-day-old culture grown in modified asparagine-glycerol salts broth with initial pH 7.0 at temperature 30∘C. Glycerol (2% and yeast extract (1.5% served as good carbon and nitrogen sources for L-asparaginase production, respectively. Cell-disrupting agents like EDTA slightly enhanced the productivity of L-asparaginase. Ours is the first paper on the production of L-asparaginase by N. levis.

  7. Construction and characterization of VL-VH tail-parallel genetically engineered antibodies against staphylococcal enterotoxins.

    Science.gov (United States)

    He, Xianzhi; Zhang, Lei; Liu, Pengchong; Liu, Li; Deng, Hui; Huang, Jinhai

    2015-03-01

    Staphylococcal enterotoxins (SEs) produced by Staphylococcus aureus have increasingly given rise to human health and food safety. Genetically engineered small molecular antibody is a useful tool in immuno-detection and treatment for clinical illness caused by SEs. In this study, we constructed the V(L)-V(H) tail-parallel genetically engineered antibody against SEs by using the repertoire of rearranged germ-line immunoglobulin variable region genes. Total RNA were extracted from six hybridoma cell lines that stably express anti-SEs antibodies. The variable region genes of light chain (V(L)) and heavy chain (V(H)) were cloned by reverse transcription PCR, and their classical murine antibody structure and functional V(D)J gene rearrangement were analyzed. To construct the eukaryotic V(H)-V(L) tail-parallel co-expression vectors based on the "5'-V(H)-ivs-IRES-V(L)-3'" mode, the ivs-IRES fragment and V(L) genes were spliced by two-step overlap extension PCR, and then, the recombined gene fragment and V(H) genes were inserted into the pcDNA3.1(+) expression vector sequentially. And then the constructed eukaryotic expression clones termed as p2C2HILO and p5C12HILO were transfected into baby hamster kidney 21 cell line, respectively. Two clonal cell lines stably expressing V(L)-V(H) tail-parallel antibodies against SEs were obtained, and the antibodies that expressed intracytoplasma were evaluated by enzyme-linked immunosorbent assay, immunofluorescence assay, and flow cytometry. SEs can stimulate the expression of some chemokines and chemokine receptors in porcine IPEC-J2 cells; mRNA transcription level of four chemokines and chemokine receptors can be blocked by the recombinant SE antibody prepared in this study. Our results showed that it is possible to get functional V(L)-V(H) tail-parallel genetically engineered antibodies in same vector using eukaryotic expression system.

  8. Puerta del Sol, Madrid

    DEFF Research Database (Denmark)

    Reeh, Henrik

    2012-01-01

    Professor Eric Corijn (Vrije Universiteit Brussel) og hans virke som dynamisk urbanist blev sat i scene, da 4Cities-masterprogrammet (4Cities.eu) underviste i Madrid midt under bosættelsen på pladsen Puerta del Sol i maj 2011. Artiklen tematiserer forbindelsen mellem det sociale og rumlige liv på...

  9. STUDIES OF SPONDYLOARTHRITIS IN RUSSIA: FROM V.M. BEKHTEREV TO OUR DAYS

    Directory of Open Access Journals (Sweden)

    A. А. Godzenko

    2016-01-01

    Full Text Available The paper briefly describes the history of spondyloarthritis  studies from the works of the outstanding Russian neurologist V.M. Bekhterev up to the present time. Special emphasis is laid on the results of the representatives of the scientific school of Professor E.R. Agababova, an organizer of the first laboratory of spondyloarthritis  in Russia. The major areas of the investigations that are currently under way in Russia are shown.

  10. Experimental study of one-stage VM cryocooler operating below 8 K

    Science.gov (United States)

    Pan, Changzhao; Zhang, Tong; Zhou, Yuan; Wang, Junjie

    2015-12-01

    The Vuilleumier (VM) refrigerator, known as heat driven refrigerator, is one kind of closed-cycle Stirling type regenerative refrigerator. The VM refrigerator with power being supplied by liquid nitrogen was proposed by Hogen and developed by Zhou, which shows great potential for development below 10 K. This paper describes the experimental development of a VM cryocooler operating below 8 K, which was achieved by using liquid nitrogen as a heat sink of middle cavity. The regenerator was optimized by using a part of metallic magnetic regenerator material Er3Ni to replace the lead sphere and a no-load temperature of 7.8 K was obtained. Then all the lead spheres were replaced by Er0.6Pr0.4 material and a no-load temperature of 7.35 K was obtained, which is the lowest temperature for this kind of refrigerator reported so far. The cooling power at 10 K is about 500 mW with a pressure ratio near 1.6 and a charge pressure of 1.8 MPa. Especially, the magnetic material Er0.6Pr0.4 was found to be a potential substitution for the conventional lead.

  11. A novel coupled VM-PT cryocooler operating at liquid helium temperature

    Science.gov (United States)

    Pan, Changzhao; Zhang, Tong; Zhou, Yuan; Wang, Junjie

    2016-07-01

    This paper presents experimental results on a novel two-stage gas-coupled VM-PT cryocooler, which is a one-stage VM cooler coupled a pulse tube cooler. In order to reach temperatures below the critical point of helium-4, a one-stage coaxial pulse tube cryocooler was gas-coupled on the cold end of the former VM cryocooler. The low temperature inertance tube and room temperature gas reservoir were used as phase shifters. The influence of room temperature double-inlet was first investigated, and the results showed that it added excessive heat loss. Then the inertance tube, regenerator and the length of the pulse tube were researched experimentally. Especially, the DC flow, whose function is similar to the double-orifice, was experimentally studied, and shown to contribute about 0.2 K for the no-load temperature. The minimum no-load temperature of 4.4 K was obtained with a pressure ratio near 1.5, working frequency of 2.2 Hz, and average pressure of 1.73 MPa.

  12. Energy Efficient Security Preserving VM Live Migration In Data Centers For Cloud Computing

    Directory of Open Access Journals (Sweden)

    Korir Sammy

    2012-03-01

    Full Text Available Virtualization is an innovation that has widely been utilized in modern data centers for cloud computing to realize energy-efficient operations of servers. Virtual machine (VM migration brings multiple benefits such as resource distribution and energy aware consolidation. Server consolidation achieves energy efficiency by enabling multiple instances of operating systems to run simultaneously on a single machine. With virtualization, it is possible to consolidate severs through VM live migration. However, migration of virtual machines brings extra energy consumption and serious security concerns that derail full adoption of this technology. In this paper, we propose a secure energy-aware provisioning of cloud computing resources on consolidated and virtualized platforms. Energy efficiency is achieved through just-right dynamic Round-Robin provisioning mechanism and the ability to power down sub-systems of a host system that are not required by VMs mapped to it. We further propose solutions to security challenges faced during VM live migration. We validate our approach by conducting a set of rigorous performance evaluation study using CloudSim toolkit. The experimental results show that our approach achieves reduced energy consumption in data centers while not compromising on security.

  13. Hypocretin-2 saporin lesions of the ventrolateral periaquaductal gray (vlPAG increase REM sleep in hypocretin knockout mice.

    Directory of Open Access Journals (Sweden)

    Satvinder Kaur

    Full Text Available Ten years ago the sleep disorder narcolepsy was linked to the neuropeptide hypocretin (HCRT, also known as orexin. This disorder is characterized by excessive day time sleepiness, inappropriate triggering of rapid-eye movement (REM sleep and cataplexy, which is a sudden loss of muscle tone during waking. It is still not known how HCRT regulates REM sleep or muscle tone since HCRT neurons are localized only in the lateral hypothalamus while REM sleep and muscle atonia are generated from the brainstem. To identify a potential neuronal circuit, the neurotoxin hypocretin-2-saporin (HCRT2-SAP was used to lesion neurons in the ventral lateral periaquaductal gray (vlPAG. The first experiment utilized hypocretin knock-out (HCRT-ko mice with the expectation that deletion of both HCRT and its target neurons would exacerbate narcoleptic symptoms. Indeed, HCRT-ko mice (n = 8 given the neurotoxin HCRT2-SAP (16.5 ng/23nl/sec each side in the vlPAG had levels of REM sleep and sleep fragmentation that were considerably higher compared to HCRT-ko given saline (+39%; n = 7 or wildtype mice (+177%; n = 9. However, cataplexy attacks did not increase, nor were levels of wake or non-REM sleep changed. Experiment 2 determined the effects in mice where HCRT was present but the downstream target neurons in the vlPAG were deleted by the neurotoxin. This experiment utilized an FVB-transgenic strain of mice where eGFP identifies GABA neurons. We verified this and also determined that eGFP neurons were immunopositive for the HCRT-2 receptor. vlPAG lesions in these mice increased REM sleep (+79% versus saline controls and it was significantly correlated (r = 0.89 with loss of eGFP neurons. These results identify the vlPAG as one site that loses its inhibitory control over REM sleep, but does not cause cataplexy, as a result of hypocretin deficiency.

  14. Reconstruction of large maxillary defect with the use of vastus lateralis (VL free flap. Case report

    Directory of Open Access Journals (Sweden)

    Nikolaos Papadogeorgakis, Vlasios Oktseloglou, Eleni Pappa, Petros Spyriounis

    2010-08-01

    Full Text Available Large defects of the maxilla, following ablative surgery, significantly affect functions such as chewing, swallowing, speech and also the aesthetics. Reconstruction of soft tissues and bone defects can be achieved, either with the use of an obturator, or with free flaps. In the literature there is no sufficient evidence on the primacy of the one or the other method. The choice depends on the judgment, the experience and the ability of the surgical team. In recent years, the use of anterolateral thigh (ALTfree flap for reconstruction of large defects of the maxillary region, has gained a lot of popularity. The vastuslateralis free flap (VL is a variation of ALT. VL’s advantages include long pedicle, easier harvesting, and fewer anatomical variations. We present a case of a 75 year old male with recurrent squamous cell carcinoma of the medial canthal region, invading the maxillary bone, the medial wall and the floor of the orbit. The patient underwent a total maxillectomy, orbital exenteration, and reconstruction with vastus lateralis free flap.

  15. Purification and biological evaluation of the metabolites produced by Streptomyces sp. TK-VL_333.

    Science.gov (United States)

    Kavitha, Alapati; Prabhakar, Peddikotla; Vijayalakshmi, Muvva; Venkateswarlu, Yenamandra

    2010-06-01

    An Actinobacterium strain isolated from laterite soils of the Guntur region was identified as Streptomyces sp. TK-VL_333 by 16S rRNA analysis. Cultural, morphological and physiological characteristics of the strain were recorded. The secondary metabolites produced by the strain cultured on galactose-tyrosine broth were extracted and concentrated followed by defatting of the crude extract with cyclohexane to afford polar and non-polar residues. Purification of the two residues by column chromatography led to isolation of five polar and one non-polar fraction. Bioactivity- guided fractions were rechromatographed on a silica gel column to obtain four compounds, namely 1H-indole-3-carboxylic acid, 2,3-dihydroxy-5-(hydroxymethyl) benzaldehyde, 4-(4-hydroxyphenoxy) butan-2-one and acetic acid-2-hydroxy-6-(3-oxo-butyl)-phenyl ester from three active polar fractions and 8-methyl decanoic acid from one non-polar fraction. The structure of the compounds was elucidated on the basis of FT-IR, mass and NMR spectroscopy. The antimicrobial activity of the bioactive compounds produced by the strain was tested against the bacteria and fungi and expressed in terms of minimum inhibitory concentration. Antifungal activity of indole-3-carboxylic acid was further evaluated under in vitro and in vivo conditions. This is the first report of 2,3-dihydroxy-5-(hydroxymethyl) benzaldehyde, 4-(4-hydroxyphenoxy) butan-2-one, acetic acid-2-hydroxy-6-(3-oxo-butyl)-phenyl ester and 8-methyl decanoic acid from the genus Streptomyces.

  16. An assessment of the ICE6G_C(VM5a) glacial isostatic adjustment model

    Science.gov (United States)

    Purcell, A.; Tregoning, P.; Dehecq, A.

    2016-05-01

    The recent release of the next-generation global ice history model, ICE6G_C(VM5a), is likely to be of interest to a wide range of disciplines including oceanography (sea level studies), space gravity (mass balance studies), glaciology, and, of course, geodynamics (Earth rheology studies). In this paper we make an assessment of some aspects of the ICE6G_C(VM5a) model and show that the published present-day radial uplift rates are too high along the eastern side of the Antarctic Peninsula (by ˜8.6 mm/yr) and beneath the Ross Ice Shelf (by ˜5 mm/yr). Furthermore, the published spherical harmonic coefficients—which are meant to represent the dimensionless present-day changes due to glacial isostatic adjustment (GIA)—contain excessive power for degree ≥90, do not agree with physical expectations and do not represent accurately the ICE6G_C(VM5a) model. We show that the excessive power in the high-degree terms produces erroneous uplift rates when the empirical relationship of Purcell et al. (2011) is applied, but when correct Stokes coefficients are used, the empirical relationship produces excellent agreement with the fully rigorous computation of the radial velocity field, subject to the caveats first noted by Purcell et al. (2011). Using the Australian National University (ANU) groups CALSEA software package, we recompute the present-day GIA signal for the ice thickness history and Earth rheology used by Peltier et al. (2015) and provide dimensionless Stokes coefficients that can be used to correct satellite altimetry observations for GIA over oceans and by the space gravity community to separate GIA and present-day mass balance change signals. We denote the new data sets as ICE6G_ANU.

  17. Using XRootD to provide caches for CernVM-FS

    CERN Document Server

    Domenighini, Matteo

    2017-01-01

    CernVM-FS recently added the possibility of using plugin for cache management. In order to investigate the capabilities and limits of such possibility, an XRootD plugin was written and benchmarked; as a byproduct, a POSIX plugin was also generated. The tests revealed that the plugin interface introduces no signicant performance over- head; moreover, the XRootD plugin performance was discovered to be worse than the ones of the built-in cache manager and the POSIX plugin. Further test of the XRootD component revealed that its per- formance is dependent on the server disk speed.

  18. Security in the CernVM File System and the Frontier Distributed Database Caching System

    CERN Document Server

    Dykstra, David

    2014-01-01

    Both the CernVM File System (CVMFS) and the Frontier Distributed Database Caching System (Frontier) distribute centrally updated data worldwide for LHC experiments using http proxy caches. Neither system provides privacy or access control on reading the data, but both control access to updates of the data and can guarantee the integrity of the data transferred to clients over the internet. CVMFS has since its early days required digital signatures and secure hashes on all distributed data, and recently both CVMFS and Frontier have added X509-based integrity checking. In this paper we detail and compare the security models of CVMFS and Frontier.

  19. Security in the CernVM File System and the Frontier Distributed Database Caching System

    Energy Technology Data Exchange (ETDEWEB)

    Dykstra, D.; Blomer, J. [CERN

    2014-01-01

    Both the CernVM File System (CVMFS) and the Frontier Distributed Database Caching System (Frontier) distribute centrally updated data worldwide for LHC experiments using http proxy caches. Neither system provides privacy or access control on reading the data, but both control access to updates of the data and can guarantee the authenticity and integrity of the data transferred to clients over the internet. CVMFS has since its early days required digital signatures and secure hashes on all distributed data, and recently Frontier has added X.509-based authenticity and integrity checking. In this paper we detail and compare the security models of CVMFS and Frontier.

  20. Dynamic virtual AliEn Grid sites on Nimbus with CernVM

    Science.gov (United States)

    Harutyunyan, A.; Buncic, P.; Freeman, T.; Keahey, K.

    2010-04-01

    We describe the work on enabling one click deployment of Grid sites of AliEn Grid framework on the Nimbus 'science cloud' at the University of Chicago. The integration of computing resources of the cloud with the resource pool of AliEn Grid is achieved by leveraging two mechanisms: the Nimbus Context Broker developed at Argonne National Laboratory and the University of Chicago, and CernVM - a baseline virtual software appliance for LHC experiments developed at CERN. Two approaches of dynamic virtual AliEn Grid site deployment are presented.

  1. Dynamic virtual AliEn Grid sites on Nimbus with CernVM

    Energy Technology Data Exchange (ETDEWEB)

    Harutyunyan, A [Armenian e-Science Foundation, Yerevan (Armenia); Buncic, P [CERN, Geneva (Switzerland); Freeman, T; Keahey, K, E-mail: hartem@mail.yerphi.a, E-mail: Predrag.Buncic@cern.c, E-mail: tfreeman@mcs.anl.go, E-mail: keahey@mcs.anl.go [University of Chicago, Chicago IL (United States)

    2010-04-01

    We describe the work on enabling one click deployment of Grid sites of AliEn Grid framework on the Nimbus 'science cloud' at the University of Chicago. The integration of computing resources of the cloud with the resource pool of AliEn Grid is achieved by leveraging two mechanisms: the Nimbus Context Broker developed at Argonne National Laboratory and the University of Chicago, and CernVM - a baseline virtual software appliance for LHC experiments developed at CERN. Two approaches of dynamic virtual AliEn Grid site deployment are presented.

  2. Physical metallurgy: Scientific school of the Academician V.M. Schastlivtsev

    Science.gov (United States)

    Tabatchikova, T. I.

    2016-04-01

    This paper is to honor Academician Vadim Mikhailovich Schastlivtsev, a prominent scientist in the field of metal physics and materials science. The article comprises an analysis of the topical issues of the physical metallurgy of the early 21st century and of the contribution of V.M. Schastlivtsev and of his school to the science of phase and structural transformations in steels. In 2015, Vadim Mikhailovich celebrates his 80th birthday, and this paper is timed to this honorable date. The list of his main publications is given in it.

  3. Generation and antitumor effects of an engineered and energized fusion protein VL-LDP-AE composed of single-domain antibody and lidamycin

    Institute of Scientific and Technical Information of China (English)

    MIAO QingFang; SHANG BoYang; OUYANG ZhiGang; LIU XiaoYun; ZHEN YongSu

    2007-01-01

    Type Ⅳ collagenase plays a pivotal role in invasion, metastasis and angiogenesis of tumor. Single domain antibodies are attractive as tumor-targeting vehicle because of their much smaller size compared with antibody molecules produced by conventional methods. Lidamycin (LDM) is a potent enediyne-containing antitumor antibiotic. In this study an engineered and energized fusion protein VL-LDP-AE composed of lidamycin and VL domain of mAb 3G11 directed against type Ⅳ collagenase was prepared using a novel two-step method. First a VL-LDP fusion protein was constructed by DNA recombination. Secondly VL-LDP-AE was obtained by molecular reconstitution. In MTT assay,VL-LDP-AE showed potent cytotoxicity to HT-1080 cells and KB cells with IC50 values of 8.55×10-12 and 1.70×10-11 mol/L, respectively. VL-LDP-AE showed antiangiogenic activity in chick chrorioallantoic membrane (CAM) assay and tube formation assay. In in vivo experiments, VL-LDP-AE was proved to be more effective than free LDM against the growth of subcutaneously transplanted hepatoma 22 in mice.Drugs were given intravenously on day 3 and 10 after tumor transplantation. Compared in terms of maximal tolerated doses, VL-LDP-AE at 0.25 mg/kg suppressed the tumor growth by 89.5%, LDM at 0.05mg/kg by 69.9%, and mitomycin at 1 mg/kg by 35%. Having a molecular weight of 25.2 kDa, VL-LDP-AE was much smaller than other reported antibody-based drugs. The results suggested that VL-LDP-AE would be a promising candidate for tumor targeting therapy. And the 2-step approach could serve as a new technology platform for making a series of highly potent engineered antibody-based drugs for a variety of cancers.

  4. Generation and antitumor effects of an engineered and energized fusion protein VL-LDP-AE composed of single-domain antibody and lidamycin

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Type IV collagenase plays a pivotal role in invasion, metastasis and angiogenesis of tumor. Single domain antibodies are attractive as tumor-targeting vehicle because of their much smaller size com-pared with antibody molecules produced by conventional methods. Lidamycin (LDM) is a potent enediyne-containing antitumor antibiotic. In this study an engineered and energized fusion protein VL-LDP-AE composed of lidamycin and VL domain of mAb 3G11 directed against type IV collagenase was prepared using a novel two-step method. First a VL-LDP fusion protein was constructed by DNA recombination. Secondly VL-LDP-AE was obtained by molecular reconstitution. In MTT assay, VL-LDP-AE showed potent cytotoxicity to HT-1080 cells and KB cells with IC50 values of 8.55×10-12 and 1.70×10-11 mol/L, respectively. VL-LDP-AE showed antiangiogenic activity in chick chrorioallantoic membrane (CAM) assay and tube formation assay. In in vivo experiments, VL-LDP-AE was proved to be more effective than free LDM against the growth of subcutaneously transplanted hepatoma 22 in mice. Drugs were given intravenously on day 3 and 10 after tumor transplantation. Compared in terms of maximal tolerated doses, VL-LDP-AE at 0.25 mg/kg suppressed the tumor growth by 89.5%, LDM at 0.05 mg/kg by 69.9%, and mitomycin at 1 mg/kg by 35%. Having a molecular weight of 25.2 kDa, VL-LDP-AE was much smaller than other reported antibody-based drugs. The results suggested that VL-LDP-AE would be a promising candidate for tumor targeting therapy. And the 2-step approach could serve as a new technology platform for making a series of highly potent engineered antibody-based drugs for a variety of cancers.

  5. Radio Brightness Temperatures and Angular Dimensions of Recently Predicted Vl-Bi Small-Scale Structures

    Science.gov (United States)

    Opher, R.

    1990-11-01

    RESUMEN. Muestro que analisis recientes publicados de fuentes de radio galacticas y extragalacticas predicen estructuras en pequera escala en fuentes de radio extendidas, remanentes de supernova, vientos protoestelares, nubes moleculares, distorsiones del fondo de 3 K, enanas blancas magnetizadas, estrellas de tipo tardio y el Sol. Discuto las temperatu- ras de brillo de radio de estas estructuras y sus ditnensiones. Muestro que estas estructuras son detectables con las sensibilidades actuales de VLBI (o en el futuro cercano). ABSTRACT. I show that recently published analysis of galactic and extragalactic radio sources make predictions of small-scale structures in extended radio sources, supernovae remnants, protostellar winds, molecu- lar clouds, distortions of the 3 K background, magnetized white dwarf binaries, late-type stars and the sun. I discuss the radio brightness temperatures of these structures and their dimensions. I show that these structures are detectable with present (or near future) VLBI sensitivities. : RADIO SOURCES-EXTENDED

  6. Telltale Animation (Sol 8)

    Science.gov (United States)

    2008-01-01

    This animation of the NASA's Phoenix Mars Lander's telltale was made from five images taken by Phoenix's Stereo Surface Imager (SSI) just after 1:10 PM local Mars time on the eighth Martian day of the mission, or Sol 8 (June 2, 2008). The images were taken with a blue filter (450 nanometer, R6) that focuses at items on the deck rather than the workspace or horizon. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  7. Telltale Animation (Sol 9)

    Science.gov (United States)

    2008-01-01

    This animation of the NASA's Phoenix Mars Lander's telltale was made from five images taken by Phoenix's Stereo Surface Imager (SSI) just after 4:37 PM local Mars time on the ninth Martian day of the mission, or Sol 9 (June 3, 2008). The images were taken with a blue filter (450 nanometer, R6) that focuses at items on the deck rather than the workspace or horizon. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  8. Telltale Animation (Sol 8)

    Science.gov (United States)

    2008-01-01

    This animation of the NASA's Phoenix Mars Lander's telltale was made from five images taken by Phoenix's Stereo Surface Imager (SSI) just after 1:10 PM local Mars time on the eighth Martian day of the mission, or Sol 8 (June 2, 2008). The images were taken with a blue filter (450 nanometer, R6) that focuses at items on the deck rather than the workspace or horizon. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  9. A fully synthetic human Fab antibody library based on fixed VH/VL framework pairings with favorable biophysical properties.

    Science.gov (United States)

    Tiller, Thomas; Schuster, Ingrid; Deppe, Dorothée; Siegers, Katja; Strohner, Ralf; Herrmann, Tanja; Berenguer, Marion; Poujol, Dominique; Stehle, Jennifer; Stark, Yvonne; Heßling, Martin; Daubert, Daniela; Felderer, Karin; Kaden, Stefan; Kölln, Johanna; Enzelberger, Markus; Urlinger, Stefanie

    2013-01-01

    This report describes the design, generation and testing of Ylanthia, a fully synthetic human Fab antibody library with 1.3E+11 clones. Ylanthia comprises 36 fixed immunoglobulin (Ig) variable heavy (VH)/variable light (VL) chain pairs, which cover a broad range of canonical complementarity-determining region (CDR) structures. The variable Ig heavy and Ig light (VH/VL) chain pairs were selected for biophysical characteristics favorable to manufacturing and development. The selection process included multiple parameters, e.g., assessment of protein expression yield, thermal stability and aggregation propensity in fragment antigen binding (Fab) and IgG1 formats, and relative Fab display rate on phage. The framework regions are fixed and the diversified CDRs were designed based on a systematic analysis of a large set of rearranged human antibody sequences. Care was taken to minimize the occurrence of potential posttranslational modification sites within the CDRs. Phage selection was performed against various antigens and unique antibodies with excellent biophysical properties were isolated. Our results confirm that quality can be built into an antibody library by prudent selection of unmodified, fully human VH/VL pairs as scaffolds.

  10. VMCast: A VM-Assisted Stability Enhancing Solution for Tree-Based Overlay Multicast.

    Science.gov (United States)

    Gu, Weidong; Zhang, Xinchang; Gong, Bin; Zhang, Wei; Wang, Lu

    2015-01-01

    Tree-based overlay multicast is an effective group communication method for media streaming applications. However, a group member's departure causes all of its descendants to be disconnected from the multicast tree for some time, which results in poor performance. The above problem is difficult to be addressed because overlay multicast tree is intrinsically instable. In this paper, we proposed a novel stability enhancing solution, VMCast, for tree-based overlay multicast. This solution uses two types of on-demand cloud virtual machines (VMs), i.e., multicast VMs (MVMs) and compensation VMs (CVMs). MVMs are used to disseminate the multicast data, whereas CVMs are used to offer streaming compensation. The used VMs in the same cloud datacenter constitute a VM cluster. Each VM cluster is responsible for a service domain (VMSD), and each group member belongs to a specific VMSD. The data source delivers the multicast data to MVMs through a reliable path, and MVMs further disseminate the data to group members along domain overlay multicast trees. The above approach structurally improves the stability of the overlay multicast tree. We further utilized CVM-based streaming compensation to enhance the stability of the data distribution in the VMSDs. VMCast can be used as an extension to existing tree-based overlay multicast solutions, to provide better services for media streaming applications. We applied VMCast to two application instances (i.e., HMTP and HCcast). The results show that it can obviously enhance the stability of the data distribution.

  11. CernVM WebAPI - Controlling Virtual Machines from the Web

    Science.gov (United States)

    Charalampidis, I.; Berzano, D.; Blomer, J.; Buncic, P.; Ganis, G.; Meusel, R.; Segal, B.

    2015-12-01

    Lately, there is a trend in scientific projects to look for computing resources in the volunteering community. In addition, to reduce the development effort required to port the scientific software stack to all the known platforms, the use of Virtual Machines (VMs)u is becoming increasingly popular. Unfortunately their use further complicates the software installation and operation, restricting the volunteer audience to sufficiently expert people. CernVM WebAPI is a software solution addressing this specific case in a way that opens wide new application opportunities. It offers a very simple API for setting-up, controlling and interfacing with a VM instance in the users computer, while in the same time offloading the user from all the burden of downloading, installing and configuring the hypervisor. WebAPI comes with a lightweight javascript library that guides the user through the application installation process. Malicious usage is prohibited by offering a per-domain PKI validation mechanism. In this contribution we will overview this new technology, discuss its security features and examine some test cases where it is already in use.

  12. VMCast: A VM-Assisted Stability Enhancing Solution for Tree-Based Overlay Multicast.

    Directory of Open Access Journals (Sweden)

    Weidong Gu

    Full Text Available Tree-based overlay multicast is an effective group communication method for media streaming applications. However, a group member's departure causes all of its descendants to be disconnected from the multicast tree for some time, which results in poor performance. The above problem is difficult to be addressed because overlay multicast tree is intrinsically instable. In this paper, we proposed a novel stability enhancing solution, VMCast, for tree-based overlay multicast. This solution uses two types of on-demand cloud virtual machines (VMs, i.e., multicast VMs (MVMs and compensation VMs (CVMs. MVMs are used to disseminate the multicast data, whereas CVMs are used to offer streaming compensation. The used VMs in the same cloud datacenter constitute a VM cluster. Each VM cluster is responsible for a service domain (VMSD, and each group member belongs to a specific VMSD. The data source delivers the multicast data to MVMs through a reliable path, and MVMs further disseminate the data to group members along domain overlay multicast trees. The above approach structurally improves the stability of the overlay multicast tree. We further utilized CVM-based streaming compensation to enhance the stability of the data distribution in the VMSDs. VMCast can be used as an extension to existing tree-based overlay multicast solutions, to provide better services for media streaming applications. We applied VMCast to two application instances (i.e., HMTP and HCcast. The results show that it can obviously enhance the stability of the data distribution.

  13. Workload-Aware and CPU Frequency Scaling for Optimal Energy Consumption in VM Allocation

    Directory of Open Access Journals (Sweden)

    Zhen Liu

    2014-01-01

    Full Text Available In the problem of VMs consolidation for cloud energy saving, different workloads will ask for different resources. Thus, considering workload characteristic, the VM placement solution will be more reasonable. In the real world, different workload works in a varied CPU utilization during its work time according to its task characteristics. That means energy consumption related to both the CPU utilization and CPU frequency. Therefore, only using the model of CPU frequency to evaluate energy consumption is insufficient. This paper theoretically verified that there will be a CPU frequency best suit for a certain CPU utilization in order to obtain the minimum energy consumption. According to this deduction, we put forward a heuristic CPU frequency scaling algorithm VP-FS (virtual machine placement with frequency scaling. In order to carry the experiments, we realized three typical greedy algorithms for VMs placement and simulate three groups of VM tasks. Our efforts show that different workloads will affect VMs allocation results. Each group of workload has its most suitable algorithm when considering the minimum used physical machines. And because of the CPU frequency scaling, VP-FS has the best results on the total energy consumption compared with the other three algorithms under any of the three groups of workloads.

  14. Nanocrystal/sol-gel nanocomposites

    Science.gov (United States)

    Petruska, Melissa A.; Klimov, Victor L.

    2007-06-05

    The present invention is directed to solid composites including colloidal nanocrystals within a sol-gel host or matrix and to processes of forming such solid composites. The present invention is further directed to alcohol soluble colloidal nanocrystals useful in formation of sol-gel based solid composites.

  15. On Use of the Variable Zagreb vM2 Index in QSPR: Boiling Points of Benzenoid Hydrocarbons

    Directory of Open Access Journals (Sweden)

    Albin Jurić

    2004-12-01

    Full Text Available The variable Zagreb vM2 index is introduced and applied to the structure-boiling point modeling of benzenoid hydrocarbons. The linear model obtained (thestandard error of estimate for the fit model Sfit=6.8 oC is much better than thecorresponding model based on the original Zagreb M2 index (Sfit=16.4 oC. Surprisingly,the model based on the variable vertex-connectivity index (Sfit=6.8 oC is comparable tothe model based on vM2 index. A comparative study with models based on the vertex-connectivity index, edge-connectivity index and several distance indices favours modelsbased on the variable Zagreb vM2 index and variable vertex-connectivity index.However, the multivariate regression with two-, three- and four-descriptors givesimproved models, the best being the model with four-descriptors (but vM2 index is notamong them with Sfit=5 oC, though the four-descriptor model contaning vM2 index isonly slightly inferior (Sfit=5.3 oC.

  16. 国外名机VM-1448功放检证

    Institute of Scientific and Technical Information of China (English)

    徐柏华

    2007-01-01

    美国的Voiceof Music Corporation(音乐之声)推出的VM-1448型多功能功率放大器,可供Phono、Toner、Tape与AOX多种音乐系统的信号进行高保真的放大。该功放由6AQ5组成双声道功率放大器,输出功率为10W×2。现经日本音响大师进行检证,表明该功放性能卓越,功能齐全,保真度高、声音动听悦耳,是一款专门用于室内播放音乐的优质功放。

  17. sol-gel

    Directory of Open Access Journals (Sweden)

    Humberto A. Monreal

    2005-01-01

    Full Text Available En este trabajo sintetizamos nanocilindros de dióxido de titanio de 30 a 400 nm por medio de ADN del plásmido pBR322 de 4,362 pares de bases y el uso de isopropóxido de titanio como precursor por medio del proceso sol-gel. Los geles resultantes fueron calcinados y los polvos caracterizados por medio de Microscopio Electrónico de Barrido (MEB, Espectroscopía de Energía Dispersiva, Microscopio Electrónico de Transmisión (MET y Difracción de Rayos X. Los resultados muestran que la síntesis in vitro de nanorods en presencia de ADN, puede ser activada. Muchas otras moléculas sintéticas pueden producirse por medio del uso de sistemas orgánicos, es así como reportamos la síntesis de híbridos hechos de ácidos nucleicos en materiales inorgánicos que pueden tener diversas aplicaciones en sistemas catalíticos, biomateriales y materiales nanoestructurados.

  18. Research and Implementation of Software Used for the Remote Control for VM700T Video Measuring Instrument

    Directory of Open Access Journals (Sweden)

    Song Wenjie

    2015-01-01

    Full Text Available In this paper, the measurement software which can be used to realize remote control of the VM700T video measuring instrument is introduced. The authors can operate VM700T by a virtual panel on the client computer, select the results that the measuring equipment displayed to transmit it, and then display the image on the VM700T virtual panel in real time. The system does have some practical values and play an important role in distance learning. The functions that the system realized mainly includes four aspects: the real-time transmission of message based on the socket technology, the serial connection between server PC and VM700T measuring equipment, the image acquisition based on VFW technology and JPEG compression and decompression, and the network transmission of image files. The actual network transmission test is shown that the data acquisition method of this thesis is flexible and convenient, and the system is of extraordinary stability. It can display the measurement results in real time and basically realize the requirements of remote control. In the content, this paper includes a summary of principle, the detailed introduction of the system realization process and some related technology.

  19. The potential of value management (VM) to improve the consideration of energy efficiency within pre-construction

    Science.gov (United States)

    Tahir, Mohamad Zamhari; Nawi, Mohd Nasrun Mohd; Rajemi, Mohamad Farizal

    2016-08-01

    Energy demand and consumption in buildings will rise rapidly in the near future because of several social economics factors and this situation occurs not only in developed countries but also in developing countries such as Malaysia. There is demand towards building with energy efficiency features at this time, however most of the current buildings types are still being constructed with conventional designs, thus contribute to inefficient of energy consumption during the operation stage of the building. This paper presents the concept and the application of Value Management (VM) approach and its potential to improve consideration of energy efficiency within pre-construction process. Based on the relevant literatures, VM has provides an efficient and effective delivery system to fulfill the objectives and client's requirements. Generally in this paper, VM is discussed and scrutinized with reference to previous studies to see how these concepts contribute to better optimize the energy consumption in a building by seeking the best value energy efficiency through the design and construction process. This paper will not draw any conclusion but rather a preliminary research to propose the most energy efficiency measures to reliably accomplish a function that will meet the client's needs, desires and expectations. For further research in future, simple quantitative industry survey and VM workshops will be conducted to validate and further improve the research.

  20. VM-ADCP measured upper ocean currents in the southeastern Arabian Sea and Equatorial Indian Ocean during December, 2000

    Digital Repository Service at National Institute of Oceanography (India)

    Murty, V.S.N.; Suryanarayana, A.; Somayajulu, Y.K.; Raikar, V.; Tilvi, V.

    The Vessel-Mounted Acoustic Doppler Current Profiler (VM-ADCP) measured currents in the upper 200 m along the cruise track covering the southeastern Arabian Sea and the Eastern Equatorial Indian Ocean during northern winter monsoon (10-31 December...

  1. VH and VL Domains of Polyspecific IgM and Monospecific IgG Antibodies Contribute Differentially to Antigen Recognition and Virus Neutralization Functions.

    Science.gov (United States)

    Pasman, Y; Kaushik, A K

    2016-07-01

    We analysed contributions of variable heavy (FdVH ) and variable light (FdVL ) domains in comparison to scFv (FdVH +FdVL ) of naturally occurring polyspecific bovine IgM with an exceptionally long CDR3H and an induced monospecific bovine herpes virus-1 (BoHV-1) neutralizing IgG1 antibody in the context of to antigen-binding site and antibody function. Various recombinant FdVH , FdVL and scFv were constructed and expressed in Pichia pastoris from the bovine IgM and IgG1 antibody encoding cDNA. The scFv1H12 showed polyspecific antigen binding similar to parent IgM antibody, though subtle differences, for example, higher thyroglobulin recognition. Such differences reflect influence of the constant region on the antigen-binding site configuration. Unlike, variable light domain FdVL 1H12, the variable heavy domain FdVH 1H12 alone recognized multiple antigens that differed from the recognition pattern of scFv1H12 (FdVH +FdVL ) and the parent IgM antibody. Nonetheless, role of FdVL 1H12 in providing structural support to FdVH in antigen recognition is noted, apart from its intrinsic antigen recognition ability. Surface plasmon resonance analysis revealed low to moderate affinity of scFv1H12 to IgG antigen. By contrast, the individual FdVH 073 and FdVL 074, originating from induced BoHV-1 neutralizing IgG1 antibody, recognized target epitope on BoHV-1 weakly when compared to FdVH +FdVL (scFv3-18L). Interestingly, both the FdVH and FdVL domains of induced IgG antibody are required to achieve BoHV-1 neutralization. To conclude, there exist subtle functional differences in the contribution of FdVH and FdVL to antigen-binding site generation of polyspecific IgM and monospecific IgG antibodies relevant to antigen recognition and virus neutralization functions.

  2. Diagnostic Value of Electrocardiographic T Wave Inversion in Lead aVL in Diagnosing Coronary Artery Disease in Patients with Chronic Stable Angina

    Directory of Open Access Journals (Sweden)

    Hatem L. Farhan

    2010-04-01

    Full Text Available Objectives: The clinical value of T wave inversion in lead aVL in diagnosing coronary artery disease (CAD remains unclear. This study aims to investigate the correlation between aVL T wave inversion and CAD in patients with chronic stable angina.Methods: Electrocardiograms (ECGs of 257 consecutive patients undergoing coronary angiography were analyzed. All patients had chronic stable angina. All patients with secondary T wave inversion had been excluded (66 patients. The remaining 191 patients constituted the study population. Detailed ECG interpretation and coronary angiographic findings were conducted by experienced cardiologists.Results: T wave inversion in aVL was identified in 89 ECGs (46.8% with definite ischemic Q-ST-T changes in different leads in 97 ECGs (50.8%. Stand alone aVL T wave inversion was found in 27 ECGs (14.1% while ischemic changes in other leads with normal aVL were identified in 36 ECGs (18.8%. The incidence of CAD was 86.3%. Single, two- and multi-vessel CAD were found in 38.8%, 28.5% and 32.7% of cases respectively. The prevalence of left main, left anterior descending, left circumflex and right coronary arteries were 4.7%, 61.2%, 29.3% and 44.5%, respectively. T wave inversion in aVL was found to be the only ECG variable significantly predicting mid segment left anterior descending artery (LAD lesions (Odds Ratio 2.93, 95% Confidence Interval 1.59-5.37, p=0.001.Conclusion: This study provides new information relating to T wave inversion in lead aVL to mid segment LAD lesions. Implication of this simple finding may help in bedside diagnosis of CAD typically mid LAD lesions. However, further studies are needed to corroborate this finding.

  3. [The toxicity of massive dosis of VM26 (4-demethyl-epipodophyllotoxin-beta-D-thenylidene glucoside). A contribution to the therapy of advanced ovarian cancer (author's transl)].

    Science.gov (United States)

    Jankowski, R P; Vahrson, H

    1977-12-09

    19 patients with advanced ovarian cancer (FIGO-stages IIb-IV) were treated by ultra-high doses of VM26 partly according to positive oncobiograms during Multiple-drug-stoss-therapy. The toxic reactions and the cytostatic effect were investigated. The range of 57,9% remissions and the moderate toxicity suggest a specific application of VM26 in advanced ovarian cancer.

  4. Advanced neuroblastoma: improved response rate using a multiagent regimen (OPEC) including sequential cisplatin and VM-26.

    Science.gov (United States)

    Shafford, E A; Rogers, D W; Pritchard, J

    1984-07-01

    Forty-two children, all over one year of age, were given vincristine, cyclophosphamide, and sequentially timed cisplatin and VM-26 (OPEC) or OPEC and doxorubicin (OPEC-D) as initial treatment for newly diagnosed stage III or IV neuroblastoma. Good partial response was achieved in 31 patients (74%) overall and in 28 (78%) of 36 patients whose treatment adhered to the chemotherapy protocol, compared with a 65% response rate achieved in a previous series of children treated with pulsed cyclophosphamide and vincristine with or without doxorubicin. Only six patients, including two of the six children whose treatment did not adhere to protocol, failed to respond, but there were five early deaths from treatment-related complications. Tumor response to OPEC, which was the less toxic of the two regimens, was at least as good as tumor response to OPEC-D. Cisplatin-induced morbidity was clinically significant in only one patient and was avoided in others by careful monitoring of glomerular filtration rate and hearing. Other centers should test the efficacy of OPEC or equivalent regimens in the treatment of advanced neuroblastoma.

  5. Optimal bandwidth-aware VM allocation for Infrastructure-as-a-Service

    CERN Document Server

    Dutta, Debojyoti; Post, Ian; Shinde, Rajendra

    2012-01-01

    Infrastructure-as-a-Service (IaaS) providers need to offer richer services to be competitive while optimizing their resource usage to keep costs down. Richer service offerings include new resource request models involving bandwidth guarantees between virtual machines (VMs). Thus we consider the following problem: given a VM request graph (where nodes are VMs and edges represent virtual network connectivity between the VMs) and a real data center topology, find an allocation of VMs to servers that satisfies the bandwidth guarantees for every virtual network edge---which maps to a path in the physical network---and minimizes congestion of the network. Previous work has shown that for arbitrary networks and requests, finding the optimal embedding satisfying bandwidth requests is $\\mathcal{NP}$-hard. However, in most data center architectures, the routing protocols employed are based on a spanning tree of the physical network. In this paper, we prove that the problem remains $\\mathcal{NP}$-hard even when the phys...

  6. THE DEFORMATION EFFECT OF VM SLIDER MULTI COMPLEX MACHINE SERIES ON PRECISION MACHINING

    Directory of Open Access Journals (Sweden)

    Berezhnoy S. B.

    2015-09-01

    Full Text Available The article is devoted to the problems of increasing the economic growth of the Russian Federation, the development of high-tech knowledge-intensive manufacturing industries on the basis of a fundamentally new technological order, new unmanned technologies. The measures to improve the accuracy of manufacturing of complex and large-sized parts. Currently, the technical level of many sectors of the economy is largely determined by the level of production of means of production. The basis of these means is the machine tool industry. On the basis of machine tool development we handle a comprehensive mechanization and automation of production processes in industry, construction, agriculture, transport and other industries. We completed a comprehensive analysis of the errors affecting the manufacturing precision parts. The activities for improving the accuracy of manufacture based on VM 32 multi-machine complex series were proposed. We made the analysis of the cutting forces influence and the cross-sectional shape of the slide on its deformation for various types of processing. We determined the optimal shape of the cross section of the slider to increase stiffness and reduce deformation of the slide in metal cutting

  7. Cytocompatibility of Highly Dispersed Nano Hydroxyapatite Sol

    Institute of Scientific and Technical Information of China (English)

    MAOXuan; WUPei-zhu; TANGShun-qing; YANYan-ling; DAIYun

    2004-01-01

    Nano hydroxyapatite (HA) crystals were prepared and dispersed in water to form HA sol by simple methods. The cytotoxicity of the sols were tested by MTT assay and lymphocytotoxicity test. Results show that the average secondary particle size of the sol containing uncalcined HA crystals is around 750 nm, within micrograde; while the sol of calcined HA contains over 88% nanoparticles with the size between 65~86 nm, in which nano HA crystals are highly dispersed. Both the HA sols have no toxicity on the proliferation of 3T3 cells and lymphocytes. It demonstrates that the nano sol is safe for the application of drug delivery.

  8. Sol-gel derived sorbents

    Science.gov (United States)

    Sigman, Michael E.; Dindal, Amy B.

    2003-11-11

    Described is a method for producing copolymerized sol-gel derived sorbent particles for the production of copolymerized sol-gel derived sorbent material. The method for producing copolymerized sol-gel derived sorbent particles comprises adding a basic solution to an aqueous metal alkoxide mixture for a pH.ltoreq.8 to hydrolyze the metal alkoxides. Then, allowing the mixture to react at room temperature for a precalculated period of time for the mixture to undergo an increased in viscosity to obtain a desired pore size and surface area. The copolymerized mixture is then added to an immiscible, nonpolar solvent that has been heated to a sufficient temperature wherein the copolymerized mixture forms a solid upon the addition. The solid is recovered from the mixture, and is ready for use in an active sampling trap or activated for use in a passive sampling trap.

  9. Sol-gel electrochromic device

    OpenAIRE

    1994-01-01

    All solid state electrochromic devices have potential applications in architectural and automotive fields to regulate the transmission and reflection of radiant energy. We present the optical and electrochemical characteristics of two solid state windows having the configuration glass/ITO/TiO2-CeO2/TiO2/TiO2-CeO2/ITO/glass and glass/ITO/WOa/TiO2/TiO2-CeO2/ITO/glass where the three internal layers have been prepared by sol gel methods. The preparation of the individual sols and some physical p...

  10. Space-geodetic and water level gauge constraints on continental uplift and tilting over North America: regional convergence of the ICE-6G_C (VM5a/VM6) models

    Science.gov (United States)

    Roy, Keven; Peltier, W. R.

    2017-08-01

    We present a series of analyses of the regional convergence of the iterative methodology that has been developed for use in the construction of global models of the glacial isostatic adjustment process. Our specific focus is upon the North American component of such models which embodied the largest concentration of grounded land ice at the Last Glacial Maximum. We show that, although the introduction of the VM6 viscosity structure helps the global ICE-6G_C (VM5a) model to improve the fit to relative sea level data from the region of forebulge collapse along the U.S. East coast, it also leads to a significant misfit to the totality of the available space-geodetic observations, which the original ICE-6G_C (VM5a) model was able to fit with high accuracy. This raises the issue of the convergence of the iterative methodology being employed in the process of model construction. We demonstrate through detailed further analysis that a fully converged solution which reconciles all available data from the continent, including additional data on the time dependent de-levelling of the Great Lakes region, is obtained through modest further modifications of both the viscosity structure of the model and the North American component of the surface mass loading history.

  11. Accelerated purification of colloidal silica sols

    Science.gov (United States)

    Bahnsen, E. B.; Garofalini, S.; Pechman, A.

    1979-01-01

    Accelerated purification process for colloidal sols using heat/deionization scheme, sharply reduces waiting time between deionization cycles from several months to a few days. Process produces same high purity silica sols as conventional methods.

  12. Puesto remisión de V. sol puesto a sol puesto, de.

    OpenAIRE

    2011-01-01

    [ES] Definición del término Puesto remisión de V. sol puesto a sol puesto, de. en el diccionario Dicter. [EN] Definition of the word Puesto remisión de V. sol puesto a sol puesto, de. in the dictionary Dicter.

  13. Spirit Drive Animation, Sols 365 to 390

    Science.gov (United States)

    2005-01-01

    This animation is built from images taken by the navigation camera on NASA's Mars Exploration Rover Spirit from the rover's 365th martian day, or sol (Jan. 11, 2005), through sol 390 (Feb. 6, 2005). During this period, Spirit covered about 80 meters (262 feet) in its climb toward 'Cumberland Ridge' in the 'Columbia Hills.' The sequence includes images from all of the sols on which Spirit drove during this period: sols 365, 366, 371, 381, 382, 386, 388 and 390.

  14. Postglacial Rebound Model ICE-6G_C (VM5a) Constrained by Geodetic and Geologic Observations

    Science.gov (United States)

    Peltier, W. R.; Argus, D. F.; Drummond, R.

    2014-12-01

    We fit the revised global model of glacial isostatic adjustment ICE-6G_C (VM5a) to all available data, consisting of several hundred GPS uplift rates, a similar number of 14C dated relative sea level histories, and 62 geologic estimates of changes in Antarctic ice thickness. The mantle viscosity profile, VM5a is a simple multi-layer fit to prior model VM2 of Peltier (1996, Science). However, the revised deglaciation history, ICE-6G (VM5a), differs significantly from previous models in the Toronto series. (1) In North America, GPS observations of vertical uplift of Earth's surface from the Canadian Base Network require the thickness of the Laurentide ice sheet at Last Glacial Maximum to be significantly revised. At Last Glacial Maximum the new model ICE-6G_C in this region, relative to ICE-5G, roughly 50 percent thicker east of Hudson Bay (in and northern Quebec and Labrador region) and roughly 30 percent thinner west of Hudson Bay (in Manitoba, Saskatchewan, and the Northwest Territories).the net change in mass, however, is small. We find that rates of gravity change determined by GRACE when corrected for the predictions of ICE-6G_C (VM5a) are significantly smaller than residuals determined on the basis of earlier models. (2) In Antarctica, we fit GPS uplift rates, geologic estimates of changes in ice thickness, and geologic constraints on the timing of ice loss. The resulting deglaciation history also differs significantly from prior models. The contribution of Antarctic ice loss to global sea level rise since Last Glacial Maximum in ICE-6G_C is 13.6 meters, less than in ICE-5G (17.5 m), but significantly larger than in both the W12A model of Whitehouse et al. [2012] (8 m) and the IJ05 R02 model of Ivins et al. [2013] (7.5 m). In ICE-6G_C rapid ice loss occurs in Antarctica from 11.5 to 8 thousands years ago, with a rapid onset at 11.5 ka thereby contributing significantly to Meltwater Pulse 1B. In ICE-6G_C (VM5a), viscous uplift of Antarctica is increasing

  15. Fluid queues driven by an M / M / 1 / N queue

    Directory of Open Access Journals (Sweden)

    Lenin R. B.

    2000-01-01

    Full Text Available In this paper, we consider fluid queue models with infinite buffer capacity which receives and releases fluid at variable rates in such a way that the net input rate of fluid into the buffer (which is negative when fluid is flowing out of the buffer is uniquely determined by the number of customers in an M / M / 1 / N queue model (that is, the fluid queue is driven by this Markovian queue with constant arrival and service rates. We use some interesting identities of tridiagonal determinants to find analytically the eigenvalues of the underlying tridiagonal matrix and hence the distribution function of the buffer occupancy. For specific cases, we verify the results available in the literature.

  16. Fast-Solving Quasi-Optimal LS-S$³$VM Based on an Extended Candidate Set.

    Science.gov (United States)

    Ma, Yuefeng; Liang, Xun; Kwok, James T; Li, Jianping; Zhou, Xiaoping; Zhang, Haiyan

    2017-02-14

    The semisupervised least squares support vector machine (LS-S³VM) is an important enhancement of least squares support vector machines in semisupervised learning. Given that most data collected from the real world are without labels, semisupervised approaches are more applicable than standard supervised approaches. Although a few training methods for LS-S³VM exist, the problem of deriving the optimal decision hyperplane efficiently and effectually has not been solved. In this paper, a fully weighted model of LS-S³VM is proposed, and a simple integer programming (IP) model is introduced through an equivalent transformation to solve the model. Based on the distances between the unlabeled data and the decision hyperplane, a new indicator is designed to represent the possibility that the label of an unlabeled datum should be reversed in each iteration during training. Using the indicator, we construct an extended candidate set consisting of the indices of unlabeled data with high possibilities, which integrates more information from unlabeled data. Our algorithm is degenerated into a special scenario of the previous algorithm when the extended candidate set is reduced into a set with only one element. Two strategies are utilized to determine the descent directions based on the extended candidate set. Furthermore, we developed a novel method for locating a good starting point based on the properties of the equivalent IP model. Combined with the extended candidate set and the carefully computed starting point, a fast algorithm to solve LS-S³VM quasi-optimally is proposed. The choice of quasi-optimal solutions results in low computational cost and avoidance of overfitting. Experiments show that our algorithm equipped with the two designed strategies is more effective than other algorithms in at least one of the following three aspects: 1) computational complexity; 2) generalization ability; and 3) flexibility. However, our algorithm and other algorithms have similar

  17. Sol-Gel Derived Hafnia Coatings

    Science.gov (United States)

    Feldman, Jay D.; Stackpoole, Mairead; Blum, Yigal; Sacks, Michael; Ellerby, Don; Johnson, Sylvia M.; Venkatapathy, Ethiras (Technical Monitor)

    2002-01-01

    Sol-gel derived hafnia coatings are being developed to provide an oxidation protection layer on ultra-high temperature ceramics for potential use in turbine engines (ultra-efficient engine technology being developed by NASA). Coatings using hafnia sol hafnia filler particles will be discussed along with sol synthesis and characterization.

  18. Molecular cloning and characterization of Vigna mungo processing enzyme 1 (VmPE-1), an asparaginyl endopeptidase possibly involved in post-translational processing of a vacuolar cysteine endopeptidase (SH-EP).

    Science.gov (United States)

    Okamoto, T; Minamikawa, T

    1999-01-01

    Asparaginyl endopeptidase is a cysteine endopeptidase that has strict substrate specificity toward the carboxy side of asparagine residues. Vigna mungo processing enzyme 1, termed VmPE-1, occurs in the cotyledons of germinated seeds of V. mungo, and is possibly involved in the post-translational processing of a vacuolar cysteine endopeptidase, designated SH-EP, which degrades seed storage protein. VmPE-1 also showed a substrate specificity to asparagine residues, and its enzymatic activity was inhibited by NEM but not E-64. In addition, purified VmPE-1 had a potential to process the recombinant SH-EP precursor to its intermediate in vitro. cDNA clones for VmPE-1 and its homologue, named VmPE-1A, were identified and sequenced, and their expressions in the cotyledons of V. mungo seedlings and other organs were investigated. VmPE-1 mRNA and SH-EP mRNA were expressed in germinated seeds at the same stage of germination although the enzymatic activity of VmPE-1 rose prior to that of SH-EP. The level of VmPE-1A mRNA continued increasing as germination proceeded. In roots, stems and leaves of fully grown plants, and in hypocotyls, VmPE-1 and VmPE-1A were little expressed. We discuss possible functions of VmPE-1 and VmPE-1A in the cotyledons of germinated seeds.

  19. Engineering the CernVM-Filesystem as a High Bandwidth Distributed Filesystem for Auxiliary Physics Data

    Science.gov (United States)

    Dykstra, D.; Bockelman, B.; Blomer, J.; Herner, K.; Levshina, T.; Slyz, M.

    2015-12-01

    A common use pattern in the computing models of particle physics experiments is running many distributed applications that read from a shared set of data files. We refer to this data is auxiliary data, to distinguish it from (a) event data from the detector (which tends to be different for every job), and (b) conditions data about the detector (which tends to be the same for each job in a batch of jobs). Relatively speaking, conditions data also tends to be relatively small per job where both event data and auxiliary data are larger per job. Unlike event data, auxiliary data comes from a limited working set of shared files. Since there is spatial locality of the auxiliary data access, the use case appears to be identical to that of the CernVM- Filesystem (CVMFS). However, we show that distributing auxiliary data through CVMFS causes the existing CVMFS infrastructure to perform poorly. We utilize a CVMFS client feature called "alien cache" to cache data on existing local high-bandwidth data servers that were engineered for storing event data. This cache is shared between the worker nodes at a site and replaces caching CVMFS files on both the worker node local disks and on the site's local squids. We have tested this alien cache with the dCache NFSv4.1 interface, Lustre, and the Hadoop Distributed File System (HDFS) FUSE interface, and measured performance. In addition, we use high-bandwidth data servers at central sites to perform the CVMFS Stratum 1 function instead of the low-bandwidth web servers deployed for the CVMFS software distribution function. We have tested this using the dCache HTTP interface. As a result, we have a design for an end-to-end high-bandwidth distributed caching read-only filesystem, using existing client software already widely deployed to grid worker nodes and existing file servers already widely installed at grid sites. Files are published in a central place and are soon available on demand throughout the grid and cached locally on the

  20. Engineering the CernVM-Filesystem as a High Bandwidth Distributed Filesystem for Auxiliary Physics Data

    Energy Technology Data Exchange (ETDEWEB)

    Dykstra, D. [Fermilab; Bockelman, B. [Nebraska U.; Blomer, J. [CERN; Herner, K. [Fermilab; Levshina, T. [Fermilab; Slyz, M. [Fermilab

    2015-12-23

    A common use pattern in the computing models of particle physics experiments is running many distributed applications that read from a shared set of data files. We refer to this data is auxiliary data, to distinguish it from (a) event data from the detector (which tends to be different for every job), and (b) conditions data about the detector (which tends to be the same for each job in a batch of jobs). Relatively speaking, conditions data also tends to be relatively small per job where both event data and auxiliary data are larger per job. Unlike event data, auxiliary data comes from a limited working set of shared files. Since there is spatial locality of the auxiliary data access, the use case appears to be identical to that of the CernVM- Filesystem (CVMFS). However, we show that distributing auxiliary data through CVMFS causes the existing CVMFS infrastructure to perform poorly. We utilize a CVMFS client feature called 'alien cache' to cache data on existing local high-bandwidth data servers that were engineered for storing event data. This cache is shared between the worker nodes at a site and replaces caching CVMFS files on both the worker node local disks and on the site's local squids. We have tested this alien cache with the dCache NFSv4.1 interface, Lustre, and the Hadoop Distributed File System (HDFS) FUSE interface, and measured performance. In addition, we use high-bandwidth data servers at central sites to perform the CVMFS Stratum 1 function instead of the low-bandwidth web servers deployed for the CVMFS software distribution function. We have tested this using the dCache HTTP interface. As a result, we have a design for an end-to-end high-bandwidth distributed caching read-only filesystem, using existing client software already widely deployed to grid worker nodes and existing file servers already widely installed at grid sites. Files are published in a central place and are soon available on demand throughout the grid and cached

  1. Type specimens of taxa of Artemisia L. (Asteraceae from Siberia and the Far East kept in the Herbarium of V.L. Komarov Botanical Insitute

    Directory of Open Access Journals (Sweden)

    A. A. Korobkov

    2015-04-01

    Full Text Available Typification of 97 Artemisia (Asteraceae taxa from Siberia and the Far East kept in the Herbarium of V.L. Komarov Botanical Institute was carried out. Holotypes for 39 taxa, lectotypes for 48 taxa, 28 syntypes and 4 isotypes are given.

  2. Increased oxidative stress and toxicity in ADH and CYP2E1 overexpressing human hepatoma VL-17A cells exposed to high glucose.

    Science.gov (United States)

    Chandrasekaran, Karthikeyan; Swaminathan, Kavitha; Kumar, S Mathan; Clemens, Dahn L; Dey, Aparajita

    2012-05-01

    High glucose mediated oxidative stress and cell death is a well documented phenomenon. Using VL-17A cells which are HepG2 cells over-expressing alcohol dehydrogenase (ADH) and cytochrome P450 2E1 (CYP2E1) and control HepG2 cells, the association of ADH and CYP2E1 with high glucose mediated oxidative stress and toxicity in liver cells was investigated. Cell viability was measured and apoptosis or necrosis was determined through caspase-3 activity, Annexin V-propidium iodide staining and detecting decreases in mitochondrial membrane potential. Reactive oxygen species, lipid peroxidation and the formation of advanced glycated-end products were assessed. The levels of several antioxidants which included glutathione, glutathione peroxidase, catalase and superoxide dismutase were altered in high glucose treated VL-17A cells. Greater toxicity was observed in VL-17A cells exposed to high glucose when compared to HepG2 cells. Oxidative stress parameters were greatly increased in high glucose exposed VL-17A cells and apoptotic cell death was observed. Inhibition of CYP2E1 or caspase 3 or addition of the antioxidant trolox led to significant decreases in high glucose mediated oxidative stress and toxicity. Thus, the over-expression of ADH and CYP2E1 in liver cells is associated with increased high glucose mediated oxidative stress and toxicity.

  3. VM600汽轮机监视仪表的功能分析和应用%Functional Analysis and Application of the VM600 Turbine Supervisory Instrumentation

    Institute of Scientific and Technical Information of China (English)

    刘海燕

    2009-01-01

    分析了印度雅幕娜电厂汽轮机监视系统所采用的瑞士VM600仪表的功能和基本构成、组态与配置,并简单说明了使用情况.系统的配置是合适的,在机组运行期间,系统能正确反映汽轮机的运行参数,未出现信号异常.

  4. Sol-gel derived ceramics

    OpenAIRE

    1990-01-01

    The synthesis of ceramic raw materials has become an important factor in ceramic technologies. The increasing demands to the performance of ceramic compounds has caused increased activities for the preparation of tailor-made raw materials. Amongst a variety of new syntheses like flame pyrolysis, reactive spray drying, plasma or laser assisted techniques, the sol-gel process plays an important and increasing role. The process describes the building up of an inorganic (in general an oxide) netw...

  5. The Sol-Gel Process

    OpenAIRE

    Khalid Suliman Aboodh

    2015-01-01

    Abstract An increasingly important application of liquid jets is the disintegration of the jet to form droplets of liquid containing nuclear fuel. These droplets are then dried and sintered to form ceramic micro spheres for use in fuel elements in nuclear reactors. The total operations required to form the droplets convert them to solids and fire them to ceramic bodies comprise what are known as Sol-Gel processes Reference 13.

  6. Antitumor activity of the two epipodophyllotoxin derivatives VP-16 and VM-26 in preclinical systems: a comparison of in vitro and in vivo drug evaluation

    DEFF Research Database (Denmark)

    Jensen, P B; Roed, H; Skovsgaard, T

    1990-01-01

    The epipodophyllotoxines VP-16 and VM-26 are chemically closely related. VM-26 has been found to be considerably more potent than VP-16 in vitro in a number of investigations. Although the drugs have been known for greater than 20 years, they have not been compared at clearly defined equitoxic do......-resistance between the two drugs suggests that they have an identical antineoplastic spectrum. VM-26 was more potent than VP-16 in vitro; however, this was not correlated to a therapeutic advantage for VM-26 over VP-16 in vivo.......The epipodophyllotoxines VP-16 and VM-26 are chemically closely related. VM-26 has been found to be considerably more potent than VP-16 in vitro in a number of investigations. Although the drugs have been known for greater than 20 years, they have not been compared at clearly defined equitoxic...... doses on an optimal schedule in vivo and it has not been clarified as to whether a therapeutic difference exists between them. A prolonged schedule is optimal for both drugs; accordingly we determined the toxicity in mice using a 5-day schedule. The dose killing 10% of the mice (LD10) was 9.4 mg...

  7. Metal-silica sol-gel materials

    Science.gov (United States)

    Stiegman, Albert E. (Inventor)

    2002-01-01

    The present invention relates to a single phase metal-silica sol-gel glass formed by the co-condensation of a transition metal with silicon atoms where the metal atoms are uniformly distributed within the sol-gel glass as individual metal centers. Any transition metal may be used in the sol-gel glasses. The present invention also relates to sensor materials where the sensor material is formed using the single phase metal-silica sol-gel glasses. The sensor materials may be in the form of a thin film or may be attached to an optical fiber. The present invention also relates to a method of sensing chemicals using the chemical sensors by monitoring the chromatic change of the metal-silica sol-gel glass when the chemical binds to the sensor. The present invention also relates to oxidation catalysts where a metal-silica sol-gel glass catalyzes the reaction. The present invention also relates to a method of performing oxidation reactions using the metal-silica sol-gel glasses. The present invention also relates to organopolymer metal-silica sol-gel composites where the pores of the metal-silica sol-gel glasses are filled with an organic polymer polymerized by the sol-gel glass.

  8. [Russian oxygen generation system "Elektron-VM": hydrogen content in electrolytically produced oxygen for breathing by International Space Station crews].

    Science.gov (United States)

    Proshkin, V Yu; Kurmazenko, E A

    2014-01-01

    The article presents the particulars of hydrogen content in electrolysis oxygen produced aboard the ISS Russian segment by oxygen generator "Elektron-VM" (SGK) for crew breathing. Hydrogen content was estimated as in the course of SGK operation in the ISS RS, so during the ground life tests. According to the investigation of hydrogen sources, the primary path of H2 appearance in oxygen is its diffusion through the porous diaphragm separating the electrolytic-cell cathode and anode chambers. Effectiveness of hydrogen oxidation in the SGK reheating unit was evaluated.

  9. Pyrroloquinoline Quinone-Dependent Cytochrome Reduction in Polyvinyl Alcohol-Degrading Pseudomonas sp. Strain VM15C

    OpenAIRE

    1989-01-01

    A polyvinyl alcohol (PVA) oxidase-deficient mutant of Pseudomonas sp. strain VM15C, strain ND1, was shown to possess PVA dehydrogenase, in which pyrroloquinoline quinone (PQQ) functions as a coenzyme. The mutant grew on PVA and required PQQ for utilization of PVA as an essential growth factor. Incubation of the membrane fraction of the mutant with PVA caused cytochrome reduction of the fraction. Furthermore, it was found that in spite of the presence of PVA oxidase, the membrane fraction of s...

  10. Effects of Temperature and Humidity Factors on the Pathogenicity of Verticillium lecanii VL17 to Trialeurodes vaporariorum Westwood%温湿度对蜡蚧轮枝菌VL17菌株侵染温室白粉虱的毒力影响

    Institute of Scientific and Technical Information of China (English)

    纪明山; 辛鑫; 王艳辉; 王瑞雪

    2010-01-01

    测定了蜡蚧轮枝菌VL17菌株在不同温湿度条件下对温室白粉虱的致病力.结果表明:在15~35℃的温度范围内,VL17菌株对温室白粉虱2龄若虫均有致病力,若虫死亡率随着温度升高而增加.在25℃温度条件下,采用1.8×107个/mL孢子悬浮液处理,温室白粉虱2龄若虫第7天死亡率达100%.湿度越大,蜡蚧轮枝菌VL17菌株对温室白粉虱的致病力越强.

  11. Hybrid sol-gel optical materials

    Science.gov (United States)

    Zeigler, John M.

    1992-01-01

    Hybrid sol-gel materials comprise silicate sols cross-linked with linear polysilane, polygermane, or poly(silane-germane). The sol-gel materials are useful as optical identifiers in tagging and verification applications and, in a different aspect, as stable, visible light transparent non-linear optical materials. Methyl or phenyl silicones, polyaryl sulfides, polyaryl ethers, and rubbery polysilanes may be used in addition to the linear polysilane. The linear polymers cross-link with the sol to form a matrix having high optical transparency, resistance to thermooxidative aging, adherence to a variety of substrates, brittleness, and a resistance to cracking during thermal cycling.

  12. SOL - SIZING AND OPTIMIZATION LANGUAGE COMPILER

    Science.gov (United States)

    Scotti, S. J.

    1994-01-01

    SOL is a computer language which is geared to solving design problems. SOL includes the mathematical modeling and logical capabilities of a computer language like FORTRAN but also includes the additional power of non-linear mathematical programming methods (i.e. numerical optimization) at the language level (as opposed to the subroutine level). The language-level use of optimization has several advantages over the traditional, subroutine-calling method of using an optimizer: first, the optimization problem is described in a concise and clear manner which closely parallels the mathematical description of optimization; second, a seamless interface is automatically established between the optimizer subroutines and the mathematical model of the system being optimized; third, the results of an optimization (objective, design variables, constraints, termination criteria, and some or all of the optimization history) are output in a form directly related to the optimization description; and finally, automatic error checking and recovery from an ill-defined system model or optimization description is facilitated by the language-level specification of the optimization problem. Thus, SOL enables rapid generation of models and solutions for optimum design problems with greater confidence that the problem is posed correctly. The SOL compiler takes SOL-language statements and generates the equivalent FORTRAN code and system calls. Because of this approach, the modeling capabilities of SOL are extended by the ability to incorporate existing FORTRAN code into a SOL program. In addition, SOL has a powerful MACRO capability. The MACRO capability of the SOL compiler effectively gives the user the ability to extend the SOL language and can be used to develop easy-to-use shorthand methods of generating complex models and solution strategies. The SOL compiler provides syntactic and semantic error-checking, error recovery, and detailed reports containing cross-references to show where

  13. Optimizing VM allocation and data placement for data-intensive applications in cloud using ACO metaheuristic algorithm

    Directory of Open Access Journals (Sweden)

    T.P. Shabeera

    2017-04-01

    Full Text Available Nowadays data-intensive applications for processing big data are being hosted in the cloud. Since the cloud environment provides virtualized resources for computation, and data-intensive applications require communication between the computing nodes, the placement of Virtual Machines (VMs and location of data affect the overall computation time. Majority of the research work reported in the current literature consider the selection of physical nodes for placing data and VMs as independent problems. This paper proposes an approach which considers VM placement and data placement hand in hand. The primary objective is to reduce cross network traffic and bandwidth usage, by placing required number of VMs and data in Physical Machines (PMs which are physically closer. The VM and data placement problem (referred as MinDistVMDataPlacement problem is defined in this paper and has been proved to be NP- Hard. This paper presents and evaluates a metaheuristic algorithm based on Ant Colony Optimization (ACO, which selects a set of adjacent PMs for placing data and VMs. Data is distributed in the physical storage devices of the selected PMs. According to the processing capacity of each PM, a set of VMs are placed on these PMs to process data stored in them. We use simulation to evaluate our algorithm. The results show that the proposed algorithm selects PMs in close proximity and the jobs executed in the VMs allocated by the proposed scheme outperforms other allocation schemes.

  14. A VL-linker-VH Orientation Dependent Single Chain Variable Antibody Fragment Against Rabies Virus G Protein with Enhanced Neutralizing Potency in vivo.

    Science.gov (United States)

    Cheng, Yue; Li, Zhuang; Xi, Hualong; Gu, Tiejun; Yuan, Ruosen; Chen, Xiaoxu; Jiang, Chunlai; Kong, Wei; Wu, Yongge

    2016-01-01

    Lethal rabies can be prevented effectively by post-exposure prophylactic (PEP) with rabies immunoglobulin (RIG). Single-chain variable fragment (scFv), which is composed of a variable heavy chain (VH) and variable light chain (VL) connected by a peptide linker, may be developed as alternative to RIG for neutralizing rabies virus (RV). However, our previously constructed scFv (FV57S) with the (NH2) VH-linker-VL (COOH) orientation showed a lower neutralizing potency than its parent RIG. This orientation may inhibit FV57S from refolding into an intact and correct conformation. Therefore, the RFV57S protein with a VL-linker-VH orientation was constructed based on FV57S. A HIS tag was incorporated to aid in purification and detection of RFV57S and FV57S. However, abilities of RFV57S and FV57S to bind with the anti-HIS tag mAb were different. Therefore, a novel direct ELISA was established by utilizing a biotin-labeled truncated glycoprotein of RV. Although with similar stability and in vitro neutralizing potency as FV57S, RFV57S showed enhanced binding ability, affinity and in vivo protective efficacy against lethal dose of RV. Our studies support the feasibility of developing a scFv with reversed orientation and provide a novel method for evaluating the binding ability, stability and affinity of engineered antibodies recognizing linear epitope.

  15. Block Gas Sol Unit in Haderslev

    DEFF Research Database (Denmark)

    Vejen, Niels Kristian

    2000-01-01

    Investigation of a SDHW system based on a Block Gas Sol Unit from Baxi A/S installed by a consumer i Haderslev, Denmark.......Investigation of a SDHW system based on a Block Gas Sol Unit from Baxi A/S installed by a consumer i Haderslev, Denmark....

  16. Pharmacokinetic and pharmacodynamic properties of SOL1

    DEFF Research Database (Denmark)

    Nelissen, J; Lemkens, P; Sann, H;

    2012-01-01

    The pharmacological profile of the novel putative neutral endopeptidase (NEP) and endothelin converting enzyme (ECE) inhibitor SOL1 was examined.......The pharmacological profile of the novel putative neutral endopeptidase (NEP) and endothelin converting enzyme (ECE) inhibitor SOL1 was examined....

  17. Determination of loss of tension in old green line that joining the furnaces VM1 e Panela1; Determinacao da queda de tensao na antiga linha verde de alimentaco dos fornos VM1 e Panela1

    Energy Technology Data Exchange (ETDEWEB)

    Panunzio, Paulo Armando; Magalhaes Sobrinho, Pedro [UNESP, Guaratingueta, SP (Brazil); Manfrin, Antonio Carlos [Villares Metals S.A., SP(Brazil). Unidade Sumare

    2009-11-01

    The objective of this work is to demonstrate the gains obtained with electrical energy, due to replacement of electric cables of air called 'power of the green line to arc furnaces VM1 and panel 1 of Villares Metals - Unit Sumare' by underground cables. We can mention other gains in safety, maintenance, environment and quality of power, but will not be measured. This substitution was motivated due to the existing line to the limit of its useful life, with restrictions to increase the load (expansion) and stops unwanted maintenance. It is emphasized that this determination is the only power loss due to ohmic resistance of bare aluminum conductor used in the old line (green). The economy demonstrated in this study is R$ 3,313.21 and 16.339752 MWh even if it is significantly reduced because there is a spare in MWh, which can be used within the company in which extensions are necessary. (author)

  18. Sol-gel composite material characteristics caused by different dielectric constant sol-gel phases

    Science.gov (United States)

    Kimoto, Keisuke; Matsumoto, Makoto; Kaneko, Tsukasa; Kobayashi, Makiko

    2016-07-01

    Ultrasonic transducers prepared by a sol-gel composite method have been investigated in the field of nondestructive testing (NDT). Sol-gel composite materials could be ideal piezoelectric materials for ultrasonic transducer applications in the NDT field, and a new sol-gel composite with desirable characteristics has been developed. Three kinds of sol-gel composite materials composed of different dielectric constant sol-gel phases, Pb(Zr,Ti)O3 (PZT), Bi4Ti3O12 (BiT), and BaTiO3 (BT), and the same piezoelectric powder phase, PbTiO3 (PT), were fabricated and their properties were compared quantitatively. As a result, the PT/BT, sol-gel composite with the highest dielectric constant sol-gel phase showed the highest d 33 and signal strength. In addition, only PT/BT was successfully poled by room-temperature corona poling with reasonable signal strength.

  19. Permanent Habitats in Earth-Sol/Mars-Sol Orbit Positions

    Science.gov (United States)

    Greenspon, J.

    Project Outpost is a manned Earth-Sol/Mars-Sol platform that enables permanent occupation in deep space. In order to develop the program elements for this complex mission, Project Outpost will rely primarily on existing/nearterm technology and hardware for the construction of its components. For the purposes of this study, four mission requirements are considered: 1. Outpost - Man's 1st purpose-produced effort of space engineering, in which astructure is developed/constructed in an environment completely alien to currentpractices for EVA guidelines. 2. Newton - a concept study developed at StarGate Research, for the development ofa modified Hohmann personnel orbital transport operating between Earth andMars. Newton would serve as the primary crew delivery apparatus throughrepeatable transfer scheduling for all Earth-Lpoint-Mars activities. Thispermanent "transit system" would establish the foundations for Solar systemcolonization. 3. Cruis - a concept study developed at StarGate Research, for the development of amodified Hohmann cargo orbital transport operating between Earth and Mars.Cruis would serve as the primary equipment delivery apparatus throughrepeatable transfer scheduling for all Earth-Lpoint-Mars activities. Thispermanent "transit system" would establish the foundations for Solar systemcolonization, and 4. Ares/Diana - a more conventional space platform configuration for Lunar andMars orbit is included as a construction baseline. The operations of these assetsare supported, and used for the support, of the outpost. Outpost would be constructed over a 27-year period of launch opportunities into Earth-Sol or Mars-Sol Lagrange orbit (E-S/M-S L1, 4 or 5). The outpost consists of an operations core with a self-contained power generation ability, a docking and maintenance structure, a Scientific Research complex and a Habitation Section. After achieving initial activation, the core will provide the support and energy required to operate the outpost in a 365

  20. Glacial Isostatic Adjustment with ICE-6G{_}C (VM5a) and Laterally Heterogeneous Mantle Viscosity

    Science.gov (United States)

    Li, Tanghua; Wu, Patrick; Steffen, Holger

    2017-04-01

    Recently, Peltier et al. (2015) introduced the ICE-6GC (VM5a) ice-earth model pair, which has successfully explained many observations of Glacial Isostatic Adjustment (GIA) simultaneously. However, their earth model used (VM5a) to infer the ice history (ICE-6G_C) is laterally homogeneous with viscosity profile varying in the radial direction only. Since surface geology and seismic tomography clearly indicates that the Earth's material properties also vary in the lateral direction, laterally heterogeneity must be included in GIA models. This can be achieved by using the Coupled-Laplace-Finite-Element method (Wu 2004) to model GIA in a spherical, self-gravitating, compressible viscoelastic Earth with linear rheology and lateral heterogeneity. In fact, Wu et al (2013) have used such model with GIA observations (e.g. global relative sea level data, GRACE data with recent hydrology contributions removed and GPS crustal uplift rates) to study the thermal contribution to lateral heterogeneity in the mantle. Their lateral viscosity perturbations are inferred from the seismic shear wave tomography model S20A (Ekstrom & Dziewonski 1998) by applying a scaling law, which includes both the effect of anharmonicity and anelasticity. The thermal contribution to seismic tomography, which is represented by the beta factor in the scaling relationship, is searched in the upper and lower mantle, for the best combination that gives the best fit between GIA predictions and observations. However, their study is based on ICE-4G only, and the new ice-earth model pair may give other best beta value combinations in the upper and lower mantle. Here, we follow the work of Wu et al (2013) but use the new ICE-6GC ice model instead. The higher resolution seismic tomography model by Bunge & Grand (2000) substitutes S20A. Earth model VM5a is used as the reference background viscosity model. The full viscosity model is obtained by superposing the background model with the lateral viscosity

  1. Drosophila vitelline membrane assembly: A critical role for an evolutionarily conserved cysteine in the “VM domain” of sV23

    OpenAIRE

    Wu, T; Manogaran, A.L; Beauchamp, J.M.; Waring, G L

    2010-01-01

    The vitelline membrane (VM), the oocyte proximal layer of the Drosophila eggshell, contains four major proteins (VMPs) that possess a highly conserved “VM domain” which includes three precisely spaced, evolutionarily conserved, cysteines (CX7CX8C). Focusing on sV23, this study showed that the three cysteines are not functionally equivalent. While substitution mutations at the first (C123S) or third (C140S) cysteines were tolerated, females with a substitution at the second position (C131S) we...

  2. La compaction des sols agricoles en Wallonie

    OpenAIRE

    Destain, Marie-France

    2014-01-01

    Dans nos pays industrialisés, l’agriculture fait appel à des machines de plus en plus lourdes. Lorsque des charges élevées sont appliquées sur des sols sensibles, une compaction du sol peut se produire conduisant à des diminutions de rendements suite aux difficultés que rencontrent les racines pour prélever l’eau et les nutriments et à la perturbation de l’activité de la pédofaune. Au niveau environnemental, du fait de la compaction, l’infiltration de l’eau dans le sol est réduite, princip...

  3. Applications of sol gel ceramic coatings

    Energy Technology Data Exchange (ETDEWEB)

    Barrow, D. [Datec Coating Corp., Kingston, Ont. (Canada)

    1996-12-31

    The sol gel method is a chemical technique in which polycrystalline ceramic films are fabricated from a solution of organometallic precursors. The technique is attractive for many industrial applications because it is a simple (films are processed in air), flexible (can be used to coat complex geometries) and cost effective (does not require expensive equipment) process. In addition, dense, high quality coatings can be achieved at much lower temperatures than is generally required for sintering bulk ceramics. In this paper the conventional sol gel method and the new datec process are reviewed and potential applications of sol gel coatings in automotive, aerospace, petrochemical, nuclear and electronic industries are discussed. (orig.)

  4. Sol-gel deposited electrochromic coatings

    Energy Technology Data Exchange (ETDEWEB)

    Ozer, N.; Lampert, C.M.

    1995-06-01

    Electrochromic devices have increasing application in display devices, switchable mirrors and smart windows. A variety of vacuum deposition technologies have been used to make electrochromic devices. The sol- gel process offers an alternative approach to the synthesis of optical quality and low cost electrochromic device layers. This study summarizes the developments in sol-gel deposited electrochromic films. The sol-gel process involves the formation of oxide networks upon hydrolysis-condensation of alkoxide precursors. In this study we cover the sol-gel deposited oxides of WO[sub 3], V[sub 2]O[sub 5], TiO[sub 2], Nb[sub 2]O[sub 5], and NiO[sub x].

  5. Sol-gel antireflective coating on plastics

    Science.gov (United States)

    Ashley, Carol S.; Reed, Scott T.

    1990-01-01

    An antireflection film made from a reliquified sol-gel hydrolyzation, condensation polymeric reaction product of a silicon, alkoxides and/or metal alkoxides, or mixtures thereof. The film is particularly useful for coating plastics.

  6. Non-Toxic Metabolic Management of Metastatic Cancer in VM Mice: Novel Combination of Ketogenic Diet, Ketone Supplementation, and Hyperbaric Oxygen Therapy.

    Science.gov (United States)

    Poff, A M; Ward, N; Seyfried, T N; Arnold, P; D'Agostino, D P

    2015-01-01

    The Warburg effect and tumor hypoxia underlie a unique cancer metabolic phenotype characterized by glucose dependency and aerobic fermentation. We previously showed that two non-toxic metabolic therapies - the ketogenic diet with concurrent hyperbaric oxygen (KD+HBOT) and dietary ketone supplementation - could increase survival time in the VM-M3 mouse model of metastatic cancer. We hypothesized that combining these therapies could provide an even greater therapeutic benefit in this model. Mice receiving the combination therapy demonstrated a marked reduction in tumor growth rate and metastatic spread, and lived twice as long as control animals. To further understand the effects of these metabolic therapies, we characterized the effects of high glucose (control), low glucose (LG), ketone supplementation (βHB), hyperbaric oxygen (HBOT), or combination therapy (LG+βHB+HBOT) on VM-M3 cells. Individually and combined, these metabolic therapies significantly decreased VM-M3 cell proliferation and viability. HBOT, alone or in combination with LG and βHB, increased ROS production in VM-M3 cells. This study strongly supports further investigation into this metabolic therapy as a potential non-toxic treatment for late-stage metastatic cancers.

  7. Unique properties of the classical bovine spongiform encephalopathy strain and its emergence from H-type bovine spongiform encephalopathy substantiated by VM transmission studies.

    Science.gov (United States)

    Bencsik, Anna; Leboidre, Mikael; Debeer, Sabine; Aufauvre, Claire; Baron, Thierry

    2013-03-01

    In addition to classical bovine spongiform encephalopathy (C-BSE), which is recognized as being at the origin of the human variant form of Creutzfeldt-Jakob disease, 2 rare phenotypes of BSE (H-type BSE [H-BSE] and L-type BSE [L-BSE]) were identified in 2004. H-type BSE and L-BSE are considered to be sporadic forms of prion disease in cattle because they differ from C-BSE with respect to incubation period, vacuolar pathology in the brain, and biochemical properties of the protease-resistant prion protein (PrP) in natural hosts and in some mouse models that have been tested. Recently, we showed that H-BSE transmitted to C57Bl/6 mice resulted in a dissociation of the phenotypic features, that is, some mice showed an H-BSE phenotype, whereas others had a C-BSE phenotype. Here, these 2 phenotypes were further studied in VM mice and compared with cattle C-BSE, H-BSE, and L-BSE. Serial passages from the C-BSE-like phenotype on VM mice retained similarities with C-BSE. Moreover, our results indicate that strains 301V and 301C derived from C-BSE transmitted to VM and C57Bl/6 mice, respectively, are fundamentally the same strain. These VM transmission studies confirm the unique properties of the C-BSE strain and support the emergence of a strain that resembles C-BSE from H-BSE.

  8. Non-Toxic Metabolic Management of Metastatic Cancer in VM Mice: Novel Combination of Ketogenic Diet, Ketone Supplementation, and Hyperbaric Oxygen Therapy.

    Directory of Open Access Journals (Sweden)

    A M Poff

    Full Text Available The Warburg effect and tumor hypoxia underlie a unique cancer metabolic phenotype characterized by glucose dependency and aerobic fermentation. We previously showed that two non-toxic metabolic therapies - the ketogenic diet with concurrent hyperbaric oxygen (KD+HBOT and dietary ketone supplementation - could increase survival time in the VM-M3 mouse model of metastatic cancer. We hypothesized that combining these therapies could provide an even greater therapeutic benefit in this model. Mice receiving the combination therapy demonstrated a marked reduction in tumor growth rate and metastatic spread, and lived twice as long as control animals. To further understand the effects of these metabolic therapies, we characterized the effects of high glucose (control, low glucose (LG, ketone supplementation (βHB, hyperbaric oxygen (HBOT, or combination therapy (LG+βHB+HBOT on VM-M3 cells. Individually and combined, these metabolic therapies significantly decreased VM-M3 cell proliferation and viability. HBOT, alone or in combination with LG and βHB, increased ROS production in VM-M3 cells. This study strongly supports further investigation into this metabolic therapy as a potential non-toxic treatment for late-stage metastatic cancers.

  9. NMDA antagonist, but not nNOS inhibitor, requires AMPA receptors in the ventromedial prefrontal cortex (vmPFC) to induce antidepressant-like effects

    DEFF Research Database (Denmark)

    Pereira, V. S.; Wegener, Gregers; Joca, S. R.

    2013-01-01

    Depressed individuals and stressed animals show enhanced levels of glutamate and neuronal nitric oxide synthase (nNOS) activity in limbic structures, including the vmPFC. Systemic administration of glutamatergic NMDA receptor antagonists or inhibitors of nitric oxide (NO) synthesis induces antide...

  10. A snapshot of the Chinese SOL Project

    Institute of Scientific and Technical Information of China (English)

    Changbao Li; Jinfeng Shi; Shouhong Sun; Jianjun Chen; Xiaohua Yang; Chen Lu; Mingsheng Chen; Zhukuan Cheng; Hongqing Ling; Ying Wang; Yongbiao Xue; Jiuhai Zhao; Chuanyou Li; Hongling Jiang; Yu Geng; Yuanyuan Dai; Huajie Fan; Dongfen Zhang; Jinfeng Chen; Fei Lu

    2008-01-01

    In 2003, the International Solanaceae Project (SOL) was initiated by an international consortium of ten countries including Korea, China, the United Kingdom, India, the Netherlands, France, Japan, Spain, Italy and the United States. The first major effort of the SOL aimed to produce a DNA sequence map for euchromatin regions of 12 chromosomes of tomato (Solanum lycopersicum) before 2010. Here we present an update on Chinese effort for sequencing the euchromatin region of chromosome 3.

  11. Sol-gel method for encapsulating molecules

    Science.gov (United States)

    Brinker, C. Jeffrey; Ashley, Carol S.; Bhatia, Rimple; Singh, Anup K.

    2002-01-01

    A method for encapsulating organic molecules, and in particular, biomolecules using sol-gel chemistry. A silica sol is prepared from an aqueous alkali metal silicate solution, such as a mixture of silicon dioxide and sodium or potassium oxide in water. The pH is adjusted to a suitably low value to stabilize the sol by minimizing the rate of siloxane condensation, thereby allowing storage stability of the sol prior to gelation. The organic molecules, generally in solution, is then added with the organic molecules being encapsulated in the sol matrix. After aging, either a thin film can be prepared or a gel can be formed with the encapsulated molecules. Depending upon the acid used, pH, and other processing conditions, the gelation time can be from one minute up to several days. In the method of the present invention, no alcohols are generated as by-products during the sol-gel and encapsulation steps. The organic molecules can be added at any desired pH value, where the pH value is generally chosen to achieve the desired reactivity of the organic molecules. The method of the present invention thereby presents a sufficiently mild encapsulation method to retain a significant portion of the activity of the biomolecules, compared with the activity of the biomolecules in free solution.

  12. Altered catalytic activity of and DNA cleavage by DNA topoisomerase II from human leukemic cells selected for resistance to VM-26.

    Science.gov (United States)

    Danks, M K; Schmidt, C A; Cirtain, M C; Suttle, D P; Beck, W T

    1988-11-29

    The simultaneous development of resistance to the cytotoxic effects of several classes of natural product anticancer drugs, after exposure to only one of these agents, is referred to as multiple drug resistance (MDR). At least two distinct mechanisms for MDR have been postulated: that associated with P-glycoprotein and that thought to be due to an alteration in DNA topoisomerase II activity (at-MDR). We describe studies with two sublines of human leukemic CCRF-CEM cells approximately 50-fold resistant (CEM/VM-1) and approximately 140-fold resistant (CEM/VM-1-5) to VM-26, a drug known to interfere with DNA topoisomerase II activity. Each of these lines is cross-resistant to other drugs known to affect topoisomerase II but not cross-resistant to vinblastine, an inhibitor of mitotic spindle formation. We found little difference in the amount of immunoreactive DNA topoisomerase II in 1.0 M NaCl nuclear extracts of the two resistant and parental cell lines. However, topoisomerase II in nuclear extracts of the resistant sublines is altered in both catalytic activity (unknotting) of and DNA cleavage by this enzyme. Also, the rate at which catenation occurs is 20-30-fold slower with the CEM/VM-1-5 preparations. The effect of VM-26 on both strand passing and DNA cleavage is inversely related to the degree of primary resistance of each cell line. Our data support the hypothesis that at-MDR is due to an alteration in topoisomerase II or in a factor modulating its activity.

  13. En-clave de Sol

    Directory of Open Access Journals (Sweden)

    Louis Manfield

    2011-12-01

    Full Text Available Ha pasado más de medio año desde que tuviera lugar el estallido reivindicativo del 16-M y las sucesivas explosiones en las que derivó este movimiento asambleario. Ninguno de los que asistieron a la manifestación del domingo, 15 de mayo, podía imaginarse que estaban pisando el centro de lo que iba a ser el escenario de la protesta colectiva más mediática de este país. Pero la Acampada ha sido algo más que el material de relleno para los medios de (desinformación y trend topic en redes sociales. Para los que nos dedicamos, en este caso, a la sociología, SOL se nos presenta como un juguete. Un sofisticado artefacto (su compleja y espesa red organizativa así lo atestiguan para poner a prueba, in situ y participando, la plasticidad y elasticidad social de la creatividad contestataria que ha convertido a un movimiento definido como indignado en un modelo autónomo de organización horizontal. Una cámara del tiempo donde el corto, el medio y largo plazo se entrecruzan con el corto, medio y largo alcance. Una ventana desde la que observar y anticipar el cambio que ya se está produciendo en el seno de la sociedad.

  14. A New Resources Provisioning Method Based on QoS Differentiation and VM Resizing in IaaS

    Directory of Open Access Journals (Sweden)

    Rongdong Hu

    2015-01-01

    Full Text Available In order to improve the host energy efficiency in IaaS, we proposed an adaptive host resource provisioning method, CoST, which is based on QoS differentiation and VM resizing. The control model can adaptively adjust control parameters according to real time application performance, in order to cope with changes in load. CoST takes advantage of the fact that different types of applications have different sensitivity degrees to performance and cost. It places two different types of VMs on the same host and dynamically adjusts their sizes based on the load forecasting and QoS feedback. It not only guarantees the performance defined in SLA, but also keeps the host running in energy-efficient state. Real Google cluster trace and host power data are used to evaluate the proposed method. Experimental results show that CoST can provide performance-sensitive application with a steady QoS and simultaneously speed up the overall processing of performance-tolerant application by 20~66%. The host energy efficiency is significantly improved by 7~23%.

  15. PROOF as a Service on the Cloud: a Virtual Analysis Facility based on the CernVM ecosystem

    CERN Document Server

    Berzano, Dario; Buncic, Predrag; Charalampidis, Ioannis; Ganis, Gerardo; Lestaris, Georgios; Meusel, René

    2014-01-01

    PROOF, the Parallel ROOT Facility, is a ROOT-based framework which enables interactive parallelism for event-based tasks on a cluster of computing nodes. Although PROOF can be used simply from within a ROOT session with no additional requirements, deploying and configuring a PROOF cluster used to be not as straightforward. Recently great efforts have been spent to make the provisioning of generic PROOF analysis facilities with zero configuration, with the added advantages of positively affecting both stability and scalability, making the deployment operations feasible even for the end user. Since a growing amount of large-scale computing resources are nowadays made available by Cloud providers in a virtualized form, we have developed the Virtual PROOF-based Analysis Facility: a cluster appliance combining the solid CernVM ecosystem and PoD (PROOF on Demand), ready to be deployed on the Cloud and leveraging some peculiar Cloud features such as elasticity. We will show how this approach is effective both for sy...

  16. DEPENDENCE OF THE SLIDER DEFORMATION AND MACHINING PRECISION ON THE MULTIPURPOSE MACHINE-TOOL COMPLEX OF VM SERIES

    Directory of Open Access Journals (Sweden)

    Berezhnoy S. B.

    2016-04-01

    Full Text Available The article is devoted to the development of high-tech metal-working industry, as well as to the use of unmanned technology. We recommended measures to improve the accuracy and quality of manufacturing of complex and large workpieces weighing up to 100 tons. To date, the technical level of many economy sectors is largely determined by the level of the production means. Based on the engineering development there is an overall automation and mechanization of production and industry processes, construction, agriculture, transport and other industries. We analyzed forms of slide sections, of errors affecting the accuracy of the workpieces manufacturing. We made simulation of the cutting forces and sliders deformations. Solved measures increase manufacturing accuracy based on multi-purpose machine tool systems of VM series. We held the analysis of the dependence of cutting forces, a slider form on its strain in different types of processing. We obtained a graph of cutting force and precision manufacturing. We defined the optimal shape of the slider cross section to increase the rigidity and reduce the slide deformation in metal cutting

  17. The SOL width and the MHD interchange instability in tokamaks

    Energy Technology Data Exchange (ETDEWEB)

    Kerner, W. [Commission of the European Communities, Abingdon (United Kingdom). JET Joint Undertaking; Pogutse, O. [Kurchatov institute, Moscow (Russian Federation)

    1994-07-01

    Instabilities in the SOL plasma can strongly influence the SOL plasma behaviour and in particular the SOL width. The SOL stability analysis shows that there exists a critical ratio of the thermal energy and the magnetic energy. If the SOL beta is greater than this critical value, the magnetic field cannot prevent the plasma displacement and a strong MHD instability in the SOL occurs. In the opposite case only slower resistive instabilities can develop. A theoretical investigation of the SOL plasma stability is presented for JET single-null and double-null divertor configurations. The dependence of the stability threshold on the SOL beta and on the sheath resistance is established. Applying a simple mixing length argument gives the scaling of the SOL width. 5 refs., 2 figs.

  18. Interference of Quorum Sensing by Delftia sp. VM4 Depends on the Activity of a Novel N-Acylhomoserine Lactone-Acylase.

    Directory of Open Access Journals (Sweden)

    Vimal B Maisuria

    Full Text Available Turf soil bacterial isolate Delftia sp. VM4 can degrade exogenous N-acyl homoserine lactone (AHL, hence it effectively attenuates the virulence of bacterial soft rot pathogen Pectobacterium carotovorum subsp. carotovorum strain BR1 (Pcc BR1 as a consequence of quorum sensing inhibition.Isolated Delftia sp. VM4 can grow in minimal medium supplemented with AHL as a sole source of carbon and energy. It also possesses the ability to degrade various AHL molecules in a short time interval. Delftia sp. VM4 suppresses AHL accumulation and the production of virulence determinant enzymes by Pcc BR1 without interference of the growth during co-culture cultivation. The quorum quenching activity was lost after the treatment with trypsin and proteinase K. The protein with quorum quenching activity was purified by three step process. Matrix assisted laser desorption/ionization-time of flight (MALDI-TOF and Mass spectrometry (MS/MS analysis revealed that the AHL degrading enzyme (82 kDa demonstrates homology with the NCBI database hypothetical protein (Daci_4366 of D. acidovorans SPH-1. The purified AHL acylase of Delftia sp. VM4 demonstrated optimum activity at 20-40°C and pH 6.2 as well as AHL acylase type mode of action. It possesses similarity with an α/β-hydrolase fold protein, which makes it unique among the known AHL acylases with domains of the N-terminal nucleophile (Ntn-hydrolase superfamily. In addition, the kinetic and thermodynamic parameters for hydrolysis of the different AHL substrates by purified AHL-acylase were estimated. Here we present the studies that investigate the mode of action and kinetics of AHL-degradation by purified AHL acylase from Delftia sp. VM4.We characterized an AHL-inactivating enzyme from Delftia sp. VM4, identified as AHL acylase showing distinctive similarity with α/β-hydrolase fold protein, described its biochemical and thermodynamic properties for the first time and revealed its potential application as an anti

  19. Digging Movie from Phoenix's Sol 18

    Science.gov (United States)

    2008-01-01

    The Surface Stereo Imager on NASA's Phoenix Mars Lander recorded the images combined into this movie of the lander's Robotic Arm enlarging and combining the two trenches informally named 'Dodo' (left) and 'Goldilocks.' The 21 images in this sequence were taken over a period of about 2 hours during Phoenix's Sol 18 (June 13, 2008), or the 18th Martian day since landing. The main purpose of the Sol 18 dig was to dig deeper for learning the depth of a hard underlying layer. A bright layer, possibly ice, was increasingly exposed as the digging progressed. Further digging and scraping in the combined Dodo-Goldilocks trench was planned for subsequent sols. The combined trench is about 20 centimeters (about 8 inches) wide. The depth at the end of the Sol 18 digging is 5 to 6 centimeters (about 2 inches). The Goldilocks trench was the source of soil samples 'Baby Bear' and 'Mama Bear,' which were collected on earlier sols and delivered to instruments on the lander deck. The Dodo trench was originally dug for practice in collecting and depositing soil samples. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  20. La compaction des sols forestiers en Wallonie

    OpenAIRE

    Destain, Marie-France

    2014-01-01

    Dans nos pays industrialisés, l’exploitation forestière fait appel à des machines de plus en plus lourdes pour assurer la vidange des coupes et le débardage des grumes. Lorsque des charges élevées sont appliquées sur des sols sensibles, une compaction du sol peut se produire entraînant une réduction de porosité, avec des conséquences néfastes sur la vitalité des peuplements. Au niveau environnemental, du fait de la compaction, l’infiltration de l’eau dans le sol est réduite, principalement...

  1. Facile and Controlled Synthesis of Silica Sol Nanospheres Through a Modified Sol-Gel Process

    Institute of Scientific and Technical Information of China (English)

    LI Jie; CHEN Lianxi; ZHANG Zhongming; JIAO Caibin

    2014-01-01

    An effective and reproducible preparation of silica sol nanospheres via a modified sol-gel process has been described. Monodisperse and stable silica sol nanospheres with uniformsize were successfully obtained through the optimized synthesis in which the mixture of tetraethyl orthosilicate (TEOS) and ethanol was followed by the addition of water and ammonium hydroxide (NH3) separately, and the size of silica sol spheres was strictly controlled in the range of 25-119 nm with a narrow size distribution by fine adjustment of several reaction parameters. Results showed that in the presence of low concentration of TEOS, spheres size rose first and reached maximum when H2O concentration was up to 66 g/L. However, the diameter of silica sol spheres decreased above 66 g/L of H2O concentration. Furthermore, it was also found that the size and size distribution of silica sol nanospheres were affected by NH3 concentration. As NH3 concentration increased from 15 to 35 g/L, the diameter declined from 83 to 64 nm. Nevertheless, higher NH3 concentration would result in relatively broad size distribution, and gelation occurred when NH3 concentration reached 44 g/L. In addition, the effect of the different feed rates of NH3 on the size growth of silica sol nanospheres was also discussed.

  2. Non-Toxic Metabolic Management of Metastatic Cancer in VM Mice: Novel Combination of Ketogenic Diet, Ketone Supplementation, and Hyperbaric Oxygen Therapy

    OpenAIRE

    2015-01-01

    The Warburg effect and tumor hypoxia underlie a unique cancer metabolic phenotype characterized by glucose dependency and aerobic fermentation. We previously showed that two non-toxic metabolic therapies - the ketogenic diet with concurrent hyperbaric oxygen (KD+HBOT) and dietary ketone supplementation - could increase survival time in the VM-M3 mouse model of metastatic cancer. We hypothesized that combining these therapies could provide an even greater therapeutic benefit in this model. Mic...

  3. The purpose of this study is to determine the clinical usefulness of Valsalva maneuver (VM) to evaluate piriform-fossae lesions on helical CT

    Energy Technology Data Exchange (ETDEWEB)

    Yamamoto, Shoji; Yasuda, Shigeo; Kimura, Shinjiro; Ito, Hisao [Chiba Univ. (Japan). Hospital; Fujimoto, Hajime; Nasu, Katsuhiro; Motoori, Ken

    1997-07-01

    Forty-four patients who were suspected hypopharyngeal carcinoma underwent both conventional CT under quiet breath holding and helical CT under Valsalva maneuver (VMCT). All patients successfully performed Valsalva maneuver during image acquisition. Normal piriform fossae were dilated well under VM. Five fossae involved by hypopharyngeal carcinoma were poorly dilated on VMCT. In conclusion VMCT is a supportive method to evaluate piriform fossae. If piriform fossae lesions were suspected on conventional CT, VMCT should be performed. (author)

  4. Ventral medial prefrontal cortex (vmPFC) as a target of the dorsolateral prefrontal modulation by transcranial direct current stimulation (tDCS) in drug addiction.

    Science.gov (United States)

    Nakamura-Palacios, Ester Miyuki; Lopes, Isabela Bittencourt Coutinho; Souza, Rodolpho Albuquerque; Klauss, Jaisa; Batista, Edson Kruger; Conti, Catarine Lima; Moscon, Janine Andrade; de Souza, Rodrigo Stênio Moll

    2016-10-01

    Here, we report some electrophysiologic and imaging effects of the transcranial direct current stimulation (tDCS) over the dorsolateral prefrontal cortex (dlPFC) in drug addiction, notably in alcohol and crack-cocaine dependence. The low resolution electromagnetic tomography (LORETA) analysis obtained through event-related potentials (ERPs) under drug-related cues, more specifically in its P3 segment (300-500 ms) in both, alcoholics and crack-cocaine users, showed that the ventral medial prefrontal cortex (vmPFC) was the brain area with the largest change towards increasing activation under drug-related cues in those subjects that kept abstinence during and after the treatment with bilateral tDCS (2 mA, 35 cm(2), cathodal left and anodal right) over dlPFC, applied repetitively (five daily sessions). In an additional study in crack-cocaine, which showed craving decreases after repetitive bilateral tDCS, we examined data originating from diffusion tensor imaging (DTI), and we found increased DTI parameters in the left connection between vmPFC and nucleus accumbens (NAcc), such as the number of voxels, fractional anisotropy (FA) and apparent diffusion coefficient (ADC), in tDCS-treated crack-cocaine users when compared to the sham-tDCS group. This increasing of DTI parameters was significantly correlated with craving decreasing after the repetitive tDCS. The vmPFC relates to the control of drug seeking, possibly by extinguishing this behavior. In our studies, the bilateral dlPFC tDCS reduced relapses and craving to the drug use, and increased the vmPFC activation under drug cues, which may be of a great importance in the control of drug use in drug addiction.

  5. Sol-gel processing of ceramics

    OpenAIRE

    Schmidt, Helmut K.

    1991-01-01

    The sol-gel process can be considered as an interesting method for the synthesis of tailor-made ceramic raw materials. Two points of view are of special interest: powder synthesis and the processing of ultrafine raw materials. In the case of powder synthesis, high quality and multicomponent powders can be synthesized by control of surface chemistry and agglomerate-free subµm powder can be obtained. The preparation of tailor-made sols offers the possibility of powder-free processing of coating...

  6. Sol-gel synthesis of lithium aluminate

    Energy Technology Data Exchange (ETDEWEB)

    Valenzuela, M.A. [Inst. Politecnico Nacional, Mexico City (Mexico); Jimenez-Becerril, J. [Inst. Nacional de Investigaciones Nucleares, Mexico City (Mexico). Dept. de Quimica]|[Univ. Autonoma Metropolitana, Iztapalapa (Mexico). Dept. de Quimica; Bulbulian, S. [Inst. Nacional de Investigaciones Nucleares, Mexico City (Mexico). Dept. de Quimica; Lara, V.H. [Univ. Autonoma Metropolitana, Iztapalapa (Mexico). Dept. de Quimica

    1996-02-01

    LiAlO{sub 2} was prepared by two sol-gel methods using simultaneous hydrolysis of the reagents: aluminum sec-butoxide/lithium methoxide and aluminum sec-butoxide/LiOH. The resulting ceramic powders were compared with those prepared by two conventional methods (i.e., solid-state fusion and peroxide). The sol-gel method provided powders with a very high {gamma}-LiAlO{sub 2} content after calcining at temperatures as low as 700 C when LiOH was used. The solids were characterized by AAS, DTA, TGA, XRD, and SEM.

  7. Collisionality dependent transport in TCV SOL plasmas

    DEFF Research Database (Denmark)

    Garcia, Odd Erik; Pitts, R.A.; Horacek, J.

    2007-01-01

    Results are presented from probe measurements in the low field side scrape-off layer (SOL) region of TCV during plasma current scan experiments. It is shown that with decreasing plasma current the radial particle density profile becomes broader and the fluctuation levels and turbulence driven...... radial particle flux increase. In the far SOL the fluctuations exhibit a high degree of statistical similarity and the particle density and flux at the wall radius scale inversely with the plasma current. Together with previous TCV density scan experiments, this indicates that plasma fluctuations...

  8. Berpikir Pseudo Penalaran Kovariasi dalam Mengkonstruksi Grafik Fungsi Kejadian Dinamik: Sebuah Analisis Berdasarkan Kerangka Kerja VL2P dan Implikasinya pada Pembelajaran Matematika

    Directory of Open Access Journals (Sweden)

    Subanji Subanji

    2016-02-01

    Full Text Available This article discusses the thinking process of pseudo covariational reasoning in constructing graphs of dynamic events. The reasoning is examined using the VL2P framework (Vinner, Lithner, Leron, and Pape. The thinking process of one student taking Calculus II course was analysed, followed with interviews, revealing that at the low level, the pseudo covariational reasoning was close to Vinner’s pseudo analytic; that higher level of reasoning was equal to Lithner’s Establish Experience; that the reasoning was dominantly affected by the first process of Leron’s Dual Process Theory; and that it took place when direct translation was involved consistent with Pape’s Direct Translation Approach. These suggest that process view be emphasized in mathematics teaching and learning.

  9. Forced recombination of psi-modified murine leukaemia virus-based vectors with murine leukaemia-like and VL30 murine endogenous retroviruses

    DEFF Research Database (Denmark)

    Mikkelsen, J G; Lund, Anders Henrik; Duch, M;

    1999-01-01

    -impaired Akv-MLV-derived vectors, we here examine putative genetic interactions between vector RNAs and copackaged endogenous retroviral RNAs of the murine leukaemia virus (MLV) and VL30 retroelement families. We show (i) that MLV recombination is not blocked by nonhomology within the 5' untranslated region...... harbouring the supposed RNA dimer-forming cis -elements and (ii) that copackaged retroviral RNAs can recombine despite pronounced sequence dissimilarity at the cross-over site(s) and within parts of the genome involved in RNA dimerization, encapsidation and strand transferring during reverse transcription....... We note that recombination-based rescue of primer binding site knock-out retroviral vectors may constitute a sensitive assay to register putative genetic interactions involving endogenous retroviral RNAs present in cells of various species....

  10. What does the simulation system SOL/PC do?

    Directory of Open Access Journals (Sweden)

    G. Magariu

    1993-06-01

    Full Text Available The simulation system SOL/PC is presented. It is intended for researching and projecting complex weakly formalized systems. SOL/PC provides models description, checking and editing, executing experiments with models and analyzing the experiments results.

  11. Électrolytes-gels pour piles au lithium système PVdF-HFP/SiO2/VL-LiTFSI

    Science.gov (United States)

    Caillon-Caravanier, M.; Claude-Montigny, B.; Lemordant, D.; Bosser, G.

    2002-04-01

    Les électrolytes-gels étudiés sont constitués du copolymère poly (fluorure de vinylidène-hexafluoropropylène) (PVdF-HFP) contenant où non de la silice et ayant absorbé un électrolyte liquide obtenu par dissolution du (trifluorométhyl sulfone) imidure de lithium (LiTFSI) dans la gamma-valérolactone (VL) ou dans le mélange VL:EC (90:10 en moles) (EC:carbonate d'éthylène). L'influence du pourcentage en sel de lithium dans l'électrolyte liquide, de la proportion de silice dans le copolymère sec et de la température sur la capacité d'absorption est étudiée. L'évolution de la conductivité en fonction de la composition de l'électrolyte-gel et de la température ainsi que l'étude de la solvatation de l'ion Li^+ par spectroscopie RAMAN ont permis de proposer un modèle de conductivité ionique pour ces matériaux. Après avoir déterminé le domaine d'électroactivité des gels, l'évolution des spectres d'impédance à l'interface Li / gel est interprétée par le modèle “couche polymère solide" (SPL).

  12. Synthesis of Zirconia Powder in Zirconia Aqueous Sol

    Institute of Scientific and Technical Information of China (English)

    LIMao-qiang

    1994-01-01

    Spherical zirconia particles formed by coagulation of colloidal particles in zirconia aqueous sol followed by calcination.The zirconia sol was prepared from zirconium oxychloride aqueous solution by adjusting its pH value.The coag-ulation resulted from addition of preopanol in the sol the coagulation mechanism was discussed based on collicd theory.

  13. Primaria. Secuencias Sol Tierra Luna. 1

    OpenAIRE

    Martínez Torregrosa, Joaquín

    2013-01-01

    Se trata de una secuencia problematizada de actividades sobre la trayectoria del Sol, para alumnos de 6 a 8 años. Forma parte de una serie de secuencias sobre "La Tierra en el Universo" para la etapa primaria. Su finalidad es ser probada en las aulas para recibir retroalimentación para su mejora.

  14. Sol-Gel Synthesis Of Aluminoborosilicate Powders

    Science.gov (United States)

    Bull, Jeffrey; Leiser, Daniel; Selvaduray, Guna

    1992-01-01

    Application of sol-gel process to synthesis of aluminoborosilicate powders shows potential for control of microstructures of materials. Development of materials having enhanced processing characteristics prove advantageous in extending high-temperature endurance of fibrous refractory composite insulation made from ceramic fibers.

  15. SOL width and intermittent fluctuations in KSTAR

    CERN Document Server

    Garcia, O E; Theodorsen, A; Bak, J -G; Hong, S -H; Kim, H -S; Pitts, R A

    2016-01-01

    Radial profiles of the ion saturation current and its fluctuation statistics are presented from probe measurements in L-mode, neutral beam heated plasmas at the outboard mid-plane region of KSTAR. The familiar two-layer structure, seen elsewhere in tokamak L-mode discharges, with a steep near-SOL profile and a broad far-SOL profile, is observed. The profile scale length in the far-SOL increases drastically with line-averaged density, thereby enhancing plasma interactions with the main chamber walls. Time series from the far-SOL region are characterised by large-amplitude bursts attributed to the radial motion of blob-like plasma filaments. Analysis of a data time series of several seconds duration under stationary plasma conditions reveals the statistical properties of these fluctuations, including the rate of level crossings and the average duration of periods spent above a given threshold level. This is shown to be in excellent agreement with predictions of a stochastic model, giving novel predictions of pl...

  16. SOL: INNOVACIÓN ON-LINE

    Directory of Open Access Journals (Sweden)

    Rubén Faúndez

    2007-11-01

    Full Text Available Las aplicaciones de simulación tienden a ser cada vez más cercanas a usuarios e industrias. Sin embargo, muchas de ellas no poseen ni la capacidad ni el conocimiento como para desarrollar internamente sus modelos de simulación. Por este motivo, y como una forma de apoyar la toma de decisiones basándose en modelos de simulación, se presenta la plataforma SOL (Simulación On Line. La metodología completa de trabajo, así como la interacción entre SOL, Empresa y Asesor, son presentadas. Su base de datos, los niveles de usuarios, sus funcionalidades, y la creación automatizada de información grafica y visual, también son explicadas. En el caso de aplicación, el uso de SOL para apoyar la toma de decisiones en una operación de movimiento de material, permite a los tomadores de decisión acceder a análisis robustos basados en información extraída de los modelos de simulación. SOL, al almacenar información, funcionar vía web, generar análisis automatizados y crear visualizaciones, permite cumplir con las expectativas de los usuarios respecto a una solución integral en simulación.

  17. One step antiglare sol-gel coating for screens by sol-gel techniques

    OpenAIRE

    Schelle, Christian; Mennig, Martin; Krug, Herbert; Jonschker, Gerhard; Schmidt, Helmut K.

    1997-01-01

    Anti-reflection coatings on glass substrates were prepared by the application of sol-gel coatings of silica containing crystalline tin oxide particles. The sol was coated on commercially available float glass by dip-coating and spin-coating techniques. Increasing the surface roughness of the float glass (factor of 50) by a particulate coating material resulted in anti-reflection effects comparable to frosted glass. Haze and clarity, which are a measure for the contrast and definition of an op...

  18. Constraining models of postglacial rebound using space geodesy: a detailed assessment of model ICE-5G (VM2) and its relatives

    Science.gov (United States)

    Argus, Donald F.; Peltier, W. Richard

    2010-05-01

    Using global positioning system, very long baseline interferometry, satellite laser ranging and Doppler Orbitography and Radiopositioning Integrated by Satellite observations, including the Canadian Base Network and Fennoscandian BIFROST array, we constrain, in models of postglacial rebound, the thickness of the ice sheets as a function of position and time and the viscosity of the mantle as a function of depth. We test model ICE-5G VM2 T90 Rot, which well fits many hundred Holocene relative sea level histories in North America, Europe and worldwide. ICE-5G is the deglaciation history having more ice in western Canada than ICE-4G; VM2 is the mantle viscosity profile having a mean upper mantle viscosity of 0.5 × 1021Pas and a mean uppermost-lower mantle viscosity of 1.6 × 1021Pas T90 is an elastic lithosphere thickness of 90 km; and Rot designates that the model includes (rotational feedback) Earth's response to the wander of the North Pole of Earth's spin axis towards Canada at a speed of ~1° Myr-1. The vertical observations in North America show that, relative to ICE-5G, the Laurentide ice sheet at last glacial maximum (LGM) at ~26 ka was (1) much thinner in southern Manitoba, (2) thinner near Yellowknife (Northwest Territories), (3) thicker in eastern and southern Quebec and (4) thicker along the northern British Columbia-Alberta border, or that ice was unloaded from these areas later (thicker) or earlier (thinner) than in ICE-5G. The data indicate that the western Laurentide ice sheet was intermediate in mass between ICE-5G and ICE-4G. The vertical observations and GRACE gravity data together suggest that the western Laurentide ice sheet was nearly as massive as that in ICE-5G but distributed more broadly across northwestern Canada. VM2 poorly fits the horizontal observations in North America, predicting places along the margins of the Laurentide ice sheet to be moving laterally away from the ice centre at 2 mm yr-1 in ICE-4G and 3 mm yr-1 in ICE-5G, in

  19. Performance evaluation of the General Electric eXplore CT 120 micro-CT using the vmCT phantom

    Energy Technology Data Exchange (ETDEWEB)

    Bahri, M.A., E-mail: M.Bahri@ulg.ac.be [ULg-Liege University, Cyclotron Research Centre, Liege, Bat. 30, Allee du 6 aout, 8 (Belgium); Warnock, G.; Plenevaux, A. [ULg-Liege University, Cyclotron Research Centre, Liege, Bat. 30, Allee du 6 aout, 8 (Belgium); Choquet, P.; Constantinesco, A. [Biophysique et Medecine Nucleaire, Hopitaux universitaires de Strasbourg, Strasbourg (France); Salmon, E.; Luxen, A. [ULg-Liege University, Cyclotron Research Centre, Liege, Bat. 30, Allee du 6 aout, 8 (Belgium); Seret, A. [ULg-Liege University, Cyclotron Research Centre, Liege, Bat. 30, Allee du 6 aout, 8 (Belgium); ULg-Liege University, Experimental Medical Imaging, Liege (Belgium)

    2011-08-21

    The eXplore CT 120 is the latest generation micro-CT from General Electric. It is equipped with a high-power tube and a flat-panel detector. It allows high resolution and high contrast fast CT scanning of small animals. The aim of this study was to compare the performance of the eXplore CT 120 with that of the eXplore Ultra, its predecessor for which the methodology using the vmCT phantom has already been described . The phantom was imaged using typical a rat (fast scan or F) or mouse (in vivo bone scan or H) scanning protocols. With the slanted edge method, a 10% modulation transfer function (MTF) was observed at 4.4 (F) and 3.9-4.4 (H) mm{sup -1} corresponding to 114 {mu}m resolution. A fairly larger MTF was obtained by the coil method with the MTF for the thinnest coil (3.3 mm{sup -1}) equal to 0.32 (F) and 0.34 (H). The geometric accuracy was better than 0.3%. There was a highly linear (R{sup 2}>0.999) relationship between measured and expected CT numbers for both the CT number accuracy and linearity sections of the phantom. A cupping effect was clearly seen on the uniform slices and the uniformity-to-noise ratio ranged from 0.52 (F) to 0.89 (H). The air CT number depended on the amount of polycarbonate surrounding the area where it was measured; a difference as high as approximately 200 HU was observed. This hindered the calibration of this scanner in HU. This is likely due to the absence of corrections for beam hardening and scatter in the reconstruction software. However in view of the high linearity of the system, the implementation of these corrections would allow a good quality calibration of the scanner in HU. In conclusion, the eXplore CT 120 achieved a better spatial resolution than the eXplore Ultra (based on previously reported specifications) and future software developments will include beam hardening and scatter corrections that will make the new generation CT scanner even more promising.

  20. ARC-VM: An architecture real options complexity-based valuation methodology for military systems-of-systems acquisitions

    Science.gov (United States)

    Domercant, Jean Charles

    The combination of today's national security environment and mandated acquisition policies makes it necessary for military systems to interoperate with each other to greater degrees. This growing interdependency results in complex Systems-of-Systems (SoS) that only continue to grow in complexity to meet evolving capability needs. Thus, timely and affordable acquisition becomes more difficult, especially in the face of mounting budgetary pressures. To counter this, architecting principles must be applied to SoS design. The research objective is to develop an Architecture Real Options Complexity-Based Valuation Methodology (ARC-VM) suitable for acquisition-level decision making, where there is a stated desire for more informed tradeoffs between cost, schedule, and performance during the early phases of design. First, a framework is introduced to measure architecture complexity as it directly relates to military SoS. Development of the framework draws upon a diverse set of disciplines, including Complexity Science, software architecting, measurement theory, and utility theory. Next, a Real Options based valuation strategy is developed using techniques established for financial stock options that have recently been adapted for use in business and engineering decisions. The derived complexity measure provides architects with an objective measure of complexity that focuses on relevant complex system attributes. These attributes are related to the organization and distribution of SoS functionality and the sharing and processing of resources. The use of Real Options provides the necessary conceptual and visual framework to quantifiably and traceably combine measured architecture complexity, time-valued performance levels, as well as programmatic risks and uncertainties. An example suppression of enemy air defenses (SEAD) capability demonstrates the development and usefulness of the resulting architecture complexity & Real Options based valuation methodology. Different

  1. Sol-gel layers for ceramic microsystems application

    Science.gov (United States)

    Czok, Mateusz; Golonka, Leszek

    2016-11-01

    This paper describes research on sol-gel solutions preparation process. Utilize of a sol-gel layers in the LTCC technology for reduction of surface roughness and influence on the ceramics properties is examined and described. The influence of sol-gel layer on possible sedimentation of dyes or biological substances in channels, mixers or chambers of ceramic microfluidic structures was investigated. Moreover, properties of sol-gel coated surfaces have been precisely examined and described. Finally, positive results of conducted experiments made it possible to design and manufacture a simple microfluidic ceramic structure, with embedded protective layer of sol-gel, for fluorescence measurements.

  2. Effect of sol size on nanofiltration performance of a sol-gel derived microporous zirconia membrane

    Institute of Scientific and Technical Information of China (English)

    Guizhi Zhu; Qian Jiang; Hong Qi; Nanping Xu

    2015-01-01

    This paper reports the effect of sol size on nanofiltration performances of sol–gel derived microporous zirconia membranes. Microstructure, pure water flux, molecular weight cut-off (MWCO) and salt retention of zirconia membranes derived from zirconia sols with different sizes were characterized. Thermal evolution, phase compo-sition, microstructure and chemical stability of unsupported zirconia membranes (powder) were determined by thermogravimetric and differential thermal analysis, X-ray diffraction, nitrogen adsorption–desorption and static solubility measurements. Results show that nanofiltration performance of zirconia membranes is highly depen-dent on sol size. The sol with an average size of 3.8 nm, which is smaller than the pore size of theγ-Al2O3 support (pore size:5–6 nm), forms a discontinuous zirconia separation layer because of excessive penetration of sol into the support. This zirconia membrane displays a MWCO value towards polyethylene glycol higher than 4000 Da. A smooth and defect-free zirconia membrane with a MWCO value of 1195 Da (pore size:1.75 nm) and relative high retention rates towards MgCl2 (76%) and CaCl2 (64%) was successfully fabricated by dip-coating the sol with an appropriate size of 8.6 nm. Zirconia sol with an average size of 12 nm exhibits colloidal nature and forms a zirconia membrane with a MWCO value of 2332 Da (pore size:2.47 nm). This promising microporous zirconia membrane presents sufficiently high chemical stability in a wide pH range of 1–12.

  3. Simultaneous measurement of tabun, sarin, soman, cyclosarin, VR, VX, and VM adducts to tyrosine in blood products by isotope dilution UHPLC-MS/MS.

    Science.gov (United States)

    Crow, Brian S; Pantazides, Brooke G; Quiñones-González, Jennifer; Garton, Joshua W; Carter, Melissa D; Perez, Jonas W; Watson, Caroline M; Tomcik, Dennis J; Crenshaw, Michael D; Brewer, Bobby N; Riches, James R; Stubbs, Sarah J; Read, Robert W; Evans, Ronald A; Thomas, Jerry D; Blake, Thomas A; Johnson, Rudolph C

    2014-10-21

    This work describes a new specific, sensitive, and rapid stable isotope dilution method for the simultaneous detection of the organophosphorus nerve agents (OPNAs) tabun (GA), sarin (GB), soman (GD), cyclosarin (GF), VR, VX, and VM adducts to tyrosine (Tyr). Serum, plasma, and lysed whole blood samples (50 μL) were prepared by protein precipitation followed by digestion with Pronase. Specific Tyr adducts were isolated from the digest by a single solid phase extraction (SPE) step, and the analytes were separated by reversed-phase ultra high performance liquid chromatography (UHPLC) gradient elution in less than 2 min. Detection was performed on a triple quadrupole tandem mass spectrometer using time-triggered selected reaction monitoring (SRM) in positive electrospray ionization (ESI) mode. The calibration range was characterized from 0.100-50.0 ng/mL for GB- and VR-Tyr and 0.250-50.0 ng/mL for GA-, GD-, GF-, and VX/VM-Tyr (R(2) ≥ 0.995). Inter- and intra-assay precision had coefficients of variation of ≤17 and ≤10%, respectively, and the measured concentration accuracies of spiked samples were within 15% of the targeted value for multiple spiking levels. The limit of detection was calculated to be 0.097, 0.027, 0.018, 0.074, 0.023, and 0.083 ng/mL for GA-, GB-, GD-, GF-, VR-, and VX/VM-Tyr, respectively. A convenience set of 96 serum samples with no known nerve agent exposure was screened and revealed no baseline values or potential interferences. This method provides a simple and highly specific diagnostic tool that may extend the time postevent that a confirmation of nerve agent exposure can be made with confidence.

  4. View Ahead After Spirit's Sol 1861 Drive

    Science.gov (United States)

    2009-01-01

    NASA's Mars Exploration Rover Spirit used its navigation camera to take the images combined into this 210-degree view of the rover's surroundings during the 1,861st to 1,863rd Martian days, or sols, of Spirit's surface mission (March 28 to 30, 2009). The center of the scene is toward the south-southwest. East is on the left. West-northwest is on the right. The rover had driven 22.7 meters (74 feet) southwestward on Sol 1861 before beginning to take the frames in this view. The drive brought Spirit past the northwestern corner of Home Plate. In this view, the western edge of Home Plate is on the portion of the horizon farthest to the left. A mound in middle distance near the center of the view is called 'Tsiolkovsky' and is about 40 meters (about 130 feet) from the rover's position. This view is presented as a cylindrical projection with geometric seam correction.

  5. Phoenix Robotic Arm's Workspace After 90 Sols

    Science.gov (United States)

    2008-01-01

    During the first 90 Martian days, or sols, after its May 25, 2008, landing on an arctic plain of Mars, NASA's Phoenix Mars Lander dug several trenches in the workspace reachable with the lander's robotic arm. The lander's Surface Stereo Imager camera recorded this view of the workspace on Sol 90, early afternoon local Mars time (overnight Aug. 25 to Aug. 26, 2008). The shadow of the the camera itself, atop its mast, is just left of the center of the image and roughly a third of a meter (one foot) wide. The workspace is on the north side of the lander. The trench just to the right of center is called 'Neverland.' The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  6. Stabilizer-free nanosized gold sols.

    Science.gov (United States)

    Andreescu, Daniel; Sau, Tapan Kumar; Goia, Dan V

    2006-06-15

    The paper describes a convenient, rapid, and reproducible method for the synthesis of stable dispersions of uniform gold nanoparticles at ambient temperatures by mixing aqueous solutions of tetrachloroauric acid and iso-ascorbic acid. The influence of the experimental conditions on the size of the gold particles and the stability of the final sols was monitored by dynamic light scattering and UV-vis spectrophotometry. It was found that the size of the resulting nanoparticles is affected by the concentration and the pH of gold solution, while the stability of the electrostatically stabilized final sols is strongly dependent on the excess of reductant in the system, the ionic strength, and the temperature of the precipitation. Since the preparation process does not require the addition of a dispersing agent, the surface of the resulting gold nanoparticles can be easily functionalized to make them suitable for applications in medicine, biology, and catalysis.

  7. Opportunity's Surroundings After Sol 1820 Drive

    Science.gov (United States)

    2009-01-01

    NASA's Mars Exploration Rover Opportunity used its navigation camera to take the images combined into this full-circle view of the rover's surroundings during the 1,820th to 1,822nd Martian days, or sols, of Opportunity's surface mission (March 7 to 9, 2009). South is at the center; north at both ends. The rover had driven 20.6 meters toward the northwest on Sol 1820 before beginning to take the frames in this view. Tracks from that drive recede southwestward. For scale, the distance between the parallel wheel tracks is about 1 meter (about 40 inches). The terrain in this portion of Mars' Meridiani Planum region includes dark-toned sand ripples and small exposures of lighter-toned bedrock. This view is presented as a cylindrical projection with geometric seam correction.

  8. Opportunity's View on Sols 1803 and 1804

    Science.gov (United States)

    2009-01-01

    NASA's Mars Exploration Rover Opportunity used its navigation camera to take the images combined into this full-circle view of the rover's surroundings during the 1,803rd and 1,804th Martian days, or sols, of Opportunity's surface mission (Feb. 18 and 19, 2009). South is at the center; north at both ends. The rover had driven 55 meters on Sol 1803 before beginning to take the frames in this view. Tracks from that drive recede northward. For scale, the distance between the parallel wheel tracks is about 1 meter (about 40 inches). The terrain in this portion of Mars' Meridiani Planum region includes dark-toned sand ripples and lighter-toned bedrock. This view is presented as a cylindrical projection with geometric seam correction.

  9. View Ahead After Spirit's Sol 1861 Drive

    Science.gov (United States)

    2009-01-01

    NASA's Mars Exploration Rover Spirit used its navigation camera to take the images combined into this 210-degree view of the rover's surroundings during the 1,861st to 1,863rd Martian days, or sols, of Spirit's surface mission (March 28 to 30, 2009). The center of the scene is toward the south-southwest. East is on the left. West-northwest is on the right. The rover had driven 22.7 meters (74 feet) southwestward on Sol 1861 before beginning to take the frames in this view. The drive brought Spirit past the northwestern corner of Home Plate. In this view, the western edge of Home Plate is on the portion of the horizon farthest to the left. A mound in middle distance near the center of the view is called 'Tsiolkovsky' and is about 40 meters (about 130 feet) from the rover's position. This view is presented as a cylindrical projection with geometric seam correction.

  10. Ring-Resonator/Sol-Gel Interferometric Immunosensor

    Science.gov (United States)

    Bearman, Gregory; Cohen, David

    2007-01-01

    A proposed biosensing system would be based on a combination of (1) a sensing volume containing antibodies immobilized in a sol-gel matrix and (2) an optical interferometer having a ring resonator configuration. The antibodies would be specific to an antigen species that one seeks to detect. In the ring resonator of the proposed system, light would make multiple passes through the sensing volume, affording greater interaction length and, hence, greater antibody- detection sensitivity.

  11. Intramural optical mapping of V(m) and Ca(i)2+ during long-duration ventricular fibrillation in canine hearts.

    Science.gov (United States)

    Kong, Wei; Ideker, Raymond E; Fast, Vladimir G

    2012-03-15

    Intramural gradients of intracellular Ca(2+) (Ca(i)(2+)) Ca(i)(2+) handling, Ca(i)(2+) oscillations, and Ca(i)(2+) transient (CaT) alternans may be important in long-duration ventricular fibrillation (LDVF). However, previous studies of Ca(i)(2+) handling have been limited to recordings from the heart surface during short-duration ventricular fibrillation. To examine whether abnormalities of intramural Ca(i)(2+) handling contribute to LDVF, we measured membrane voltage (V(m)) and Ca(i)(2+) during pacing and LDVF in six perfused canine hearts using five eight-fiber optrodes. Measurements were grouped into epicardial, midwall, and endocardial layers. We found that during pacing at 350-ms cycle length, CaT duration was slightly longer (by ≃10%) in endocardial layers than in epicardial layers, whereas action potential duration (APD) exhibited no difference. Rapid pacing at 150-ms cycle length caused alternans in both APD (APD-ALT) and CaT amplitude (CaA-ALT) without significant transmural differences. For 93% of optrode recordings, CaA-ALT was transmurally concordant, whereas APD-ALT was either concordant (36%) or discordant (54%), suggesting that APD-ALT was not caused by CaA-ALT. During LDVF, V(m) and Ca(i)(2+) progressively desynchronized when not every action potential was followed by a CaT. Such desynchronization developed faster in the epicardium than in the other layers. In addition, CaT duration strongly increased (by ∼240% at 5 min of LDVF), whereas APD shortened (by ∼17%). CaT rises always followed V(m) upstrokes during pacing and LDVF. In conclusion, the fact that V(m) upstrokes always preceded CaTs indicates that spontaneous Ca(i)(2+) oscillations in the working myocardium were not likely the reason for LDVF maintenance. Strong V(m)-Ca(i)(2+) desynchronization and the occurrence of long CaTs during LDVF indicate severely impaired Ca(i)(2+) handling and may potentially contribute to LDVF maintenance.

  12. Alkali cold gelation of whey proteins. Part I: sol-gel-sol(-gel) transitions.

    Science.gov (United States)

    Mercadé-Prieto, Ruben; Gunasekaran, Sundaram

    2009-05-19

    The cold gelation of preheated whey protein isolate (WPI) solutions at alkaline conditions (pH>10) has been studied to better understand the effect of NaOH in the formation and destruction of whey protein aggregates and gels. Oscillatory rheology has been used to follow the gelation process, resulting in novel and different gelation profiles with the gelation pH. At low alkaline pH, typical sol-gel transitions are observed, as in many other biopolymers. At pH>11.5, the system gels quickly, after approximately 300 s, followed by a slow degelation step that transforms the gel to a viscous solution. Finally, there is a second gelation step. This results in a surprising sol-gel-sol-gel transition in time at constant gelation conditions. At very high pH (>12.5), the degelation step is very severe, and the second gelation step is not observed, resulting in a sol-gel-sol transition. The first quick gelation step is related to the quick swelling of the WPI aggregates in alkali, as observed from light scattering, which enables the formation of new noncovalent interactions to form a gel network. These interactions are argued to be destroyed in the subsequent degelation step. Disulfide cross-linking is observed only in the second gelation step, not in the first step.

  13. Restricted VH/VL usage and limited mutations in gluten-specific IgA of coeliac disease lesion plasma cells.

    Science.gov (United States)

    Steinsbø, Øyvind; Henry Dunand, Carole J; Huang, Min; Mesin, Luka; Salgado-Ferrer, Marlene; Lundin, Knut E A; Jahnsen, Jørgen; Wilson, Patrick C; Sollid, Ludvig M

    2014-06-09

    Coeliac disease (CD), an enteropathy caused by cereal gluten ingestion, is characterized by CD4(+) T cells recognizing deamidated gluten and by antibodies reactive to gluten or the self-antigen transglutaminase 2 (TG2). TG2-specific immunoglobulin A (IgA) of plasma cells (PCs) from CD lesions have limited somatic hypermutation (SHM). Here we report that gluten-specific IgA of lesion-resident PCs share this feature. Monoclonal antibodies were expression cloned from single PCs of patients either isolated from cultures with reactivity to complex deamidated gluten antigen or by sorting with gluten peptide tetramers. Typically, the antibodies bind gluten peptides related to T-cell epitopes and many have higher reactivity to deamidated peptides. There is restricted VH and VL combination and usage among the antibodies. Limited SHM suggests that a common factor governs the mutation level in PCs producing TG2- and gluten-specific IgA. The antibodies have potential use for diagnosis of CD and for detection of gluten.

  14. Epoxy Sol-Gel Hybrid Thermosets

    Directory of Open Access Journals (Sweden)

    Angels Serra

    2016-02-01

    Full Text Available Sol-gel methodologies are advantageous in the preparation of hybrid materials in front of the conventional addition of nanoparticles, because of the fine dispersion of the inorganic phase that can be reached in epoxy matrices. In addition, the use of organoalkoxysilanes as coupling agents allows covalent linkage between organic and inorganic phases, which is the key point in the improvement of mechanical properties. The sol-gel process involves hydrolysis and condensation reactions under mild conditions, starting from hydrolysable metal alkoxides, generally alkoxy silanes. Using the sol-gel procedure, the viscosity of the formulation is maintained, which is an important issue in coating applications, whereas the transparency of the polymer matrix is also maintained. However, only the proper combination of the chemistries and functionalities of both organic and inorganic structures leads to thermosets with the desired characteristics. The adequate preparation of hybrid epoxy thermosets enables their improvement in characteristics such as mechanical properties (modulus, hardness, scratch resistance, thermal and flame resistance, corrosion and antimicrobial protection, and even optical performance among others.

  15. Sol-Gel Manufactured Energetic Materials

    Science.gov (United States)

    Simpson, Randall L.; Lee, Ronald S.; Tillotson, Thomas M.; Hrubesh, Lawrence W.; Swansiger, Rosalind W.; Fox, Glenn A.

    2005-05-17

    Sol-gel chemistry is used for the preparation of energetic materials (explosives, propellants and pyrotechnics) with improved homogeneity, and/or which can be cast to near-net shape, and/or made into precision molding powders. The sol-gel method is a synthetic chemical process where reactive monomers are mixed into a solution, polymerization occurs leading to a highly cross-linked three dimensional solid network resulting in a gel. The energetic materials can be incorporated during the formation of the solution or during the gel stage of the process. The composition, pore, and primary particle sizes, gel time, surface areas, and density may be tailored and controlled by the solution chemistry. The gel is then dried using supercritical extraction to produce a highly porous low density aerogel or by controlled slow evaporation to produce a xerogel. Applying stress during the extraction phase can result in high density materials. Thus, the sol-gel method can be used for precision detonator explosive manufacturing as well as producing precision explosives, propellants, and pyrotechnics, along with high power composite energetic materials.

  16. Platinum states in citrate sols by EXAFS.

    Science.gov (United States)

    Lin, Chia-Shiang; Khan, Maksudur R; Lin, Shawn D

    2005-07-01

    Platinum sols have been prepared by citrate reduction in the temperature range of 343-363 K. The Pt state in the solution was examined by EXAFS (extended X-ray absorption fine-structure spectroscopy). It did not show any PtPt bonding, a characteristic for reduced Pt sols. EXAFS model fitting further proved the presence of PtO with 4 oxygen neighbors, which suggests a tetraplanar coordination configuration. The possibility of neighboring Pt sharing oxygen ligand or the formation of PtO(x) is rejected by EXAFS model fitting. Citrate was found to be the most likely ligand to orient its oxygen end toward a charged Pt center. Thus we have revealed that the citrate treatment at this temperature range was clearly insufficient to reduce H2PtCl(6(aq)). Neither an extended period of reaction time nor an excess citrate reduced the Pt precursor. It is therefore highly recommended that the citrate sols should be carefully prepared and used.

  17. SOL Width Scaling in the MAST Tokamak

    Science.gov (United States)

    Ahn, Joon-Wook; Counsell, Glenn; Connor, Jack; Kirk, Andrew

    2002-11-01

    Target heat loads are determined in large part by the upstream SOL heat flux width, Δ_h. Considerable effort has been made in the past to develop analytical and empirical scalings for Δh to allow reliable estimates to be made for the next-step device. The development of scalings for a large spherical tokamak (ST) such as MAST is particularly important both for development of the ST concept and for improving the robustness of scalings derived for conventional tokamaks. A first such scaling has been developed in MAST DND plasmas. The scaling was developed by flux-mapping data from the target Langmuir probe arrays to the mid-plane and fitting to key upstream parameters such as P_SOL, bar ne and q_95. In order to minimise the effects of co-linearity, dedicated campaigns were undertaken to explore the widest possible range of each parameter while keeping the remainder as fixed as possible. Initial results indicate a weak inverse dependence on P_SOL and approximately linear dependence on bar n_e. Scalings derived from consideration of theoretical edge transport models and integration with data from conventional devices is under way. The established scaling laws could be used for the extrapolations to the future machine such as Spherical Tokamak Power Plant (STPP). This work is jointly funded by Euratom and UK Department of Trade and Industry. J-W. Ahn would like to recognise the support of a grant from the British Foreign & Commonwealth Office.

  18. Sol-gel processing to form doped sol-gel monoliths inside hollow core optical fiber and sol-gel core fiber devices made thereby

    Science.gov (United States)

    Shaw, Harry C. (Inventor); Ott, Melanie N. (Inventor); Manuel, Michele V. (Inventor)

    2002-01-01

    A process of fabricating a fiber device includes providing a hollow core fiber, and forming a sol-gel material inside the hollow core fiber. The hollow core fiber is preferably an optical fiber, and the sol-gel material is doped with a dopant. Devices made in this manner includes a wide variety of sensors.

  19. Ionogel Electrolytes through Sol-Gel Processing

    Science.gov (United States)

    Horowitz, Ariel I.

    Electrical energy needs have intensified due to the ubiquity of personal electronics, the decarbonization of energy services through electrification, and the use of intermittent renewable energy sources. Despite developments in mechanical and thermal methods, electrochemical technologies are the most convenient and effective means of storing electrical energy. These technologies include both electrochemical cells, commonly called batteries, and electrochemical double-layer capacitors, or "supercapacitors", which store energy electrostatically. Both device types require an ion-conducting electrolyte. Current devices use solutions of complex salts in organic solvents, leading to both toxicity and flammability concerns. These drawbacks can be avoided by replacing conventional electrolytes with room-temperature molten salts, known as ionic liquids (ILs). ILs are non-volatile, non-flammable, and offer high conductivity and good electrochemical stability. Device mass can be reduced by combining ILs with a solid scaffold material to form an "ionogel," further improving performance metrics. In this work, sol-gel chemistry is explored as a means of forming ionogel electrolytes. Sol-gel chemistry is a solution-based, industrially-relevant, well-studied technique by which solids such as silica can be formed in situ. Previous works used a simple acid-catalyzed sol-gel reaction to create brittle, glassy ionogels. Here, both the range of products that can be accomplished through sol-gel processing and the understanding of interactions between ILs and the sol-gel reaction network are greatly expanded. This work introduces novel ionogel materials, including soft and compliant silica-supported ionogels and PDMS-supported ionogels. The impacts of the reactive formulation, IL identity, and casting time are detailed. It is demonstrated that variations in formulation can lead to rapid gelation and open pore structures in the silica scaffold or slow gelation and more dense silica

  20. Sol-gel synthesis of hydroxyapatite; Sintese de hidroxiapatita via sol-gel

    Energy Technology Data Exchange (ETDEWEB)

    Zupanski, M.D.; Lucena, M.P.P.; Bergmann, C.P., E-mail: michelledunin@yahoo.com.b [Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS (Brazil)

    2010-07-01

    Hydroxyapatite (HAp) has been established as the calcium phosphate based compound with most applications in the biological field. Among the numerous techniques for synthesis of HAp, the sol-gel processing route affords great control over purity and formed phases using low processing temperatures. In addition, the sol-gel approach offers an option for homogeneous HAp coating on metal substrates, as well as the ability to generate nanocrystalline powders. In this work, the sol-gel synthesis of HAp was investigated employing triethyl phosphate and calcium nitrate tetrahydrate as phosphorous and calcium precursors, respectively. The aging effect on phase composition and powder morphology of the final product was studied in terms of temperature and aging time. The powders were studied by using X-ray diffraction, Fourier transform infrared spectroscopy, particle size distribution by laser diffraction and scanning electron microscopy. (author)

  1. Organically modified sols as pseudostationary phases for microchip electrophoresis.

    Science.gov (United States)

    Pumera, Martin; Wang, Joseph; Grushka, Eli; Lev, Ovadia

    2007-04-30

    We demonstrate that the selectivity of microchip electrophoresis separations is greatly improved by the presence of organically modified silica (Ormosil) sols in the run buffer. A negatively-charged N-(trimethoxysilylpropyl)ethylenediamine triacetic-acid (TETT)-based sol is used for improving the selectivity between nitroaromatic explosives and a methyltrimethoxysilane (MTMOS)-based sol is employed for enhancing the microchip separation of environmental pollutants, aminophenols. These sols are added to the run buffer and act as pseudostationary phases. Their presence in the run buffer changes the apparent mobility of studied solutes, and leads to a higher resolution. The observed mobilities changes reflect the interactions between the Ormosil sols and the solutes. Relevant experimental variables have been characterized and optimized. The diverse chemistry of Ormosil sols should be extremely useful for tailoring the selectivity of a wide range of electrophoresis microchip separations.

  2. Externally applied electric fields up to 1.6 × 10(5) V/m do not affect the homogeneous nucleation of ice in supercooled water.

    Science.gov (United States)

    Stan, Claudiu A; Tang, Sindy K Y; Bishop, Kyle J M; Whitesides, George M

    2011-02-10

    The freezing of water can initiate at electrically conducting electrodes kept at a high electric potential or at charged electrically insulating surfaces. The microscopic mechanisms of these phenomena are unknown, but they must involve interactions between water molecules and electric fields. This paper investigates the effect of uniform electric fields on the homogeneous nucleation of ice in supercooled water. Electric fields were applied across drops of water immersed in a perfluorinated liquid using a parallel-plate capacitor; the drops traveled in a microchannel and were supercooled until they froze due to the homogeneous nucleation of ice. The distribution of freezing temperatures of drops depended on the rate of nucleation of ice, and the sensitivity of measurements allowed detection of changes by a factor of 1.5 in the rate of nucleation. Sinusoidal alternation of the electric field at frequencies from 3 to 100 kHz prevented free ions present in water from screening the electric field in the bulk of drops. Uniform electric fields in water with amplitudes up to (1.6 ± 0.4) × 10(5) V/m neither enhanced nor suppressed the homogeneous nucleation of ice. Estimations based on thermodynamic models suggest that fields in the range of 10(7)-10(8) V/m might cause an observable increase in the rate of nucleation.

  3. Inhibition of BCL-2 leads to increased apoptosis and delayed neuronal differentiation in human ReNcell VM cells in vitro.

    Science.gov (United States)

    Fröhlich, Michael; Jaeger, Alexandra; Weiss, Dieter G; Kriehuber, Ralf

    2016-02-01

    BCL-2 is a multifunctional protein involved in the regulation of apoptosis, cell cycle progression and neural developmental processes. Its function in the latter process is not well understood and needs further elucidation. Therefore, we characterized the protein expression kinetics of BCL-2 and associated regulatory proteins of the intrinsic apoptosis pathway during the process of neuronal differentiation in ReNcell VM cells with and without functional inhibition of BCL-2 by its competitive ligand HA14-1. Inhibition of BCL-2 caused a diminished BCL-2 expression and higher levels of cleaved BAX, activated Caspase-3 and cleaved PARP, all pro-apoptotic markers, when compared with untreated differentiating cells. In parallel, flow cytometric analysis of HA14-1-treated cells revealed a delayed differentiation into HuC/D+ neuronal cells when compared to untreated differentiating cells. In conclusion, BCL-2 possess a protective function in fully differentiated ReNcell VM cells. We propose that the pro-survival signaling of BCL-2 is closely connected with its stimulatory effects on neurogenesis of human neural progenitor cells.

  4. Examples of Sol-Solitons in the Pseudo-Riemannian case

    CERN Document Server

    Onda, Kensuke

    2011-01-01

    This paper provides a study of sol-solitons in the pseudo-Riemannian case. In the Riemannian case, all nontrivial homogeneous sol-soliton are expanding sol-solitons. In this paper, we obtain steady sol-solitons and shrinking sol-solitons in the Lorentzian setting.

  5. Progress on sol-gel sphere-pac development

    Energy Technology Data Exchange (ETDEWEB)

    Suchomel, R R

    1978-01-01

    The ORNL sol-gel program is reviewed briefly. Advantages of the sol-gel sphere-pac are listed. Three sizes of microspheres are being used; the two largest sized fractions are blended and then loaded into the fuel rod, followed by packing of the smallest microspheres into void spaces using a low-energy vibrator. Sol-gel sphere-pac also appears attractive for breeder reactor fuel fabrication. (DLC)

  6. Sol-gel processing with inorganic metal salt precursors

    Science.gov (United States)

    Hu, Zhong-Cheng

    2004-10-19

    Methods for sol-gel processing that generally involve mixing together an inorganic metal salt, water, and a water miscible alcohol or other organic solvent, at room temperature with a macromolecular dispersant material, such as hydroxypropyl cellulose (HPC) added. The resulting homogenous solution is incubated at a desired temperature and time to result in a desired product. The methods enable production of high quality sols and gels at lower temperatures than standard methods. The methods enable production of nanosize sols from inorganic metal salts. The methods offer sol-gel processing from inorganic metal salts.

  7. Method of making ionic liquid mediated sol-gel sorbents

    Energy Technology Data Exchange (ETDEWEB)

    Malik, Abdul; Shearrow, Anne M.

    2017-01-31

    Ionic liquid (IL)-mediated sol-gel hybrid organic-inorganic materials present enormous potential for effective use in analytical microextraction. One obstacle to materializing this prospect arises from high viscosity of ILs significantly slowing down sol-gel reactions. A method was developed which provides phosphonium-based, pyridinium-based, and imidazolium-based IL-mediated advanced sol-gel organic-inorganic hybrid materials for capillary microextraction. Scanning electron microscopy results demonstrate that ILs can serve as porogenic agents in sol-gel reactions. IL-mediated sol-gel coatings prepared with silanol-terminated polymers provided up to 28 times higher extractions compared to analogous sol-gel coatings prepared without any IL in the sol solution. This study shows that IL-generated porous morphology alone is not enough to provide effective extraction media: careful choice of the organic polymer and the precursor with close sol-gel reactivity must be made to ensure effective chemical bonding of the organic polymer to the created sol-gel material to be able to provide the desired sorbent characteristics.

  8. Effect of sol-age on the surface and optical properties of sol-gel derived mesoporous zirconia thin films

    Directory of Open Access Journals (Sweden)

    Manish Kumar

    2011-06-01

    Full Text Available Mesoporous ZrO2 thin films have been deposited by a modified sol-gel dip coating technique using HCl as catalyst. Effects of sol-age on the surface and on the optical properties are studied. Transmission electron micrographs of the films reveal the pore dimensions in mesoporous regime. A strong correlation in surface topography with sol-age has been observed where increase in sol-age induces a systematic enhancement in the value of root mean square roughness of the films. Optical study shows that deposited films have high transmittance and an enhancement of 5.6 times in porosity in films prepared with sol-age of 10 days with respect to that of 1 day. Band gap estimation by Tauc's plots of films is observed to 5.74 eV, which shows invariance with the sol-age.

  9. Fundamental characteristics of the expressed immunoglobulin VH and VL repertoire in different canine breeds in comparison with those of humans and mice.

    Science.gov (United States)

    Steiniger, Sebastian C J; Dunkle, William E; Bammert, Gary F; Wilson, Thomas L; Krishnan, Abhiram; Dunham, Steven A; Ippolito, Gregory C; Bainbridge, Graeme

    2014-05-01

    Complementarity determining regions (CDR) are responsible for binding antigen and provide substantial diversity to the antibody repertoire, with VH CDR3 of the immunoglobulin variable heavy (VH) domain playing a dominant role. In this study, we examined 1200 unique canine VH and 500 unique variable light (VL) sequences of large and small canine breeds derived from peripheral B cells. Unlike the human and murine repertoire, the canine repertoire is heavily dominated by the Canis lupus familiaris IGHV1 subgroup, evolutionarily closest to the human IGHV3 subgroup. Our studies clearly show that the productive canine repertoire of all analyzed breeds shows similarities to both human and mouse; however, there are distinct differences in terms of VH CDR3 length and amino acid paratope composition. In comparison with the human and murine antibody repertoire, canine VH CDR3 regions are shorter in length than the human counterparts, but longer than the murine VH CDR3. Similar to corresponding human and mouse VH CDR3, the amino acids at the base of the VH CDR3 loop are strictly conserved. For identical CDR positions, there were significant changes in chemical paratope composition. Similar to human and mouse repertoires, the neutral amino acids tyrosine, glycine and serine dominate the canine VH CDR3 interval (comprising 35%) although the interval is nonetheless relatively depleted of tyrosine when compared to human and mouse. Furthermore, canine VH CDR3 displays an overrepresentation of the neutral amino acid threonine and the negatively charged aspartic acid while proline content is similar to that in the human repertoire. In general, the canine repertoire shows a bias towards small, negatively charged amino acids. Overall, this analysis suggests that functional canine therapeutic antibodies can be obtained from human and mouse sequences by methods of speciation and affinity maturation.

  10. sol y playa: el caso de Tenerife

    Directory of Open Access Journals (Sweden)

    Ricardo J. Díaz Armas

    2008-01-01

    Full Text Available El turismo del vino tiene una concepción distinta en un destino masivo de sol y playa. En este caso el enoturismo convive con ese modelo turístico y es un producto complementario que favorece la diversificación en la oferta actual. El turismo del vino puede complementar la ya existente oferta turística, con lo que las regiones, turísticas y a la vez viníferas, podrían apoyarse en las experiencias y conocimiento del vino por parte del visitante y utilizarlas como hecho diferencial competitivo frente a otros destinos de sol y playa que no poseen esta particularidad. Con ello además se favorecerá el lanzamiento del producto turístico del vino, pues la demanda latente ya esta en las zonas turísticas que rodean el área vinícola. En este sentido, una vez que se descubren las motivaciones para acudir al destino Tenerife, se localiza un mercado sensible a la ruta del vino Tacoronte-Acentejo en el asentamiento turístico del Puerto de la Cruz (una de las principales zonas turísticas de Tenerife. Así, tras conocer los beneficios buscados por el visitante del Puerto de la Cruz, se ha contrastado la existencia de dos segmentos latentes que pueden ser atraídos hacia la oferta actual de la ruta del vino en Tacoronte-Acentejo, al verificar que persiguen, además del clima y el sol y playa (principales motivaciones para viajar al destino Tenerife, otros beneficios que son susceptibles de ser ofertados por la ruta del vino.

  11. Thermal properties of wool fabric treated by phosphorus-doped silica sols through sol-gel method

    Directory of Open Access Journals (Sweden)

    Zhang Wei

    2014-01-01

    Full Text Available Wool fabric was treated with silica sol and phosphorus doped silica sol by sol-gel method in order to improve its thermal properties and flame retardance. The thermal stability, combustion behavior, and smoke suppression of the control and finished wool fabric were analyzed using thermogravimetric analysis, limited oxygen index, micro combustion calorimeter, and smoke chamber. The results showed that wool fabric treated by phosphorus doped silica sol had excellent thermal properties and flame retardance with higher final char residue and LOI value. Furthermore, heat release rate and smoke density results indicated the safety performance of the treated wool fabric on fire.

  12. Sol-gel overganger for microsilica

    OpenAIRE

    2003-01-01

    Oppgaven er en grunnleggende undersøkelse av sol-gel overganger i vandige dispersjoner av Microsilica. Den er delt i tre deler: 1) undersøkelse av Microsilica kolloid- og overflateegenskaper 2) identifisering av parametere som er av størst betydning for gelingsforløpet i Microsilica slurryer og 3) en nærmere undersøkelse av mulige mekanismer for gelingen. Prøven av Microsilica som ble benyttet i forsøkene var en relativt ren kvalitet med et SiO2 -innhold på 97,3 vekt%. P...

  13. Preparation and characterization of nano hydroxyapatite sol

    Institute of Scientific and Technical Information of China (English)

    王友法; 闫玉华; 任卫; 曹献英; 李世普

    2004-01-01

    Nano hydroxyapatite has special biological effects when it interacts with cells. The method of preparation of nano hydroxyapatite crystals in water and the stability of hydroxyapatite sol are reported. Nanometer sized hydroxyapatite crystals were synthesized by precipitation with monocalcium phosphate and calcium hydroxide. The size of the crystals is 30 - 50 nm as determined by laser light scattering and transmission electron microscopy (TEM). The shape of the crystals particles is either sphere or rod-shaped. Beijing Synchrotron Radiation Facility (BSRF) micro-probe X-ray fluorescence analysis and TEM analysis reveal that hydroxyapatite crystals can pass human liver cancer cell membrane in the form of particles.

  14. Preparation of counterion stabilized concentrated silver sols.

    Science.gov (United States)

    LaPlante, Sylas; Halaciuga, Ionel; Goia, Dan V

    2011-07-01

    A strategy for obtaining stable concentrated silver dispersions without dedicated stabilizing agents is presented. This approach consists of rapidly mixing aqueous solutions of silver salicylate and ascorbic acid. By using salicylate as Ag(+) counterion, it is possible to prepare stable sols with metal concentrations up to two orders of magnitude higher than with silver nitrate. The stabilizing effect of the counterion is the result of a decreased ionic strength due to salicylate protonation and its adsorption on the surface of silver. Both effects increase the range of the electrostatic repulsive forces by expanding the electrical double layer. Copyright © 2011 Elsevier Inc. All rights reserved.

  15. MIPAS temperature from the stratosphere to the lower thermosphere: comparison of version vM21 with ACE-FTS, MLS, OSIRIS, SABER, SOFIE and lidar measurements

    Directory of Open Access Journals (Sweden)

    M. García-Comas

    2014-07-01

    Full Text Available We present vM21 MIPAS temperatures from the lower stratosphere to the lower thermosphere, which cover all optimized resolution measurements performed by MIPAS in the Middle Atmosphere, Upper Atmosphere and NoctiLucent Cloud modes during its lifetime. i.e., from January 2005 to March 2012. The main upgrades with respect to the previous version of MIPAS temperatures (vM11 are the update of the spectroscopic database, the use of a different climatology of atomic oxygen and carbon dioxide, and the improvement of important technical aspects of the retrieval setup (temperature gradient along the line of sight and offset regularizations, apodization accuracy. Additionally, an updated version of ESA calibrated L1b spectra (5.02/5.06 is used. The vM21 temperatures correct the main systematic errors of the previous version because they on average provide a 1–2 K warmer stratopause and middle mesosphere, and a 6–10 K colder mesopause (except in high latitude summers and lower thermosphere. These lead to a remarkable improvement of MIPAS comparisons with ACE-FTS, MLS, OSIRIS, SABER, SOFIE and the two Rayleigh lidars at Mauna Loa and Table Mountain, that, with few specific exceptions, typically exhibit differences smaller than 1 K below 50 km and than 2 K at 50–80 km in spring, autumn, winter at all latitudes, and summer at low to mid-latitudes. Differences in the high latitude summers are typically smaller than 1 K below 50 km, smaller than 2 K at 50–65 km and 5 K at 65–80 km. Differences with the other instruments in the mid-mesosphere are generally negative. MIPAS mesopause is within 4 K of the other instruments measurements, except in the high latitude summers, where it is within 5–10 K of the other instruments, being warmer than SABER, MLS and OSIRIS and colder than ACE-FTS and SOFIE. The agreement in the lower thermosphere is typically better than 5 K, except for high latitudes during spring and summer, where MIPAS usually exhibits larger

  16. Stability engineering of anti-EGFR scFv antibodies by rational design of a lambda-to-kappa swap of the VL framework using a structure-guided approach.

    Science.gov (United States)

    Lehmann, Andreas; Wixted, Josephine H F; Shapovalov, Maxim V; Roder, Heinrich; Dunbrack, Roland L; Robinson, Matthew K

    2015-01-01

    Phage-display technology facilitates rapid selection of antigen-specific single-chain variable fragment (scFv) antibodies from large recombinant libraries. ScFv antibodies, composed of a VH and VL domain, are readily engineered into multimeric formats for the development of diagnostics and targeted therapies. However, the recombinant nature of the selection strategy can result in VH and VL domains with sub-optimal biophysical properties, such as reduced thermodynamic stability and enhanced aggregation propensity, which lead to poor production and limited application. We found that the C10 anti-epidermal growth factor receptor (EGFR) scFv, and its affinity mutant, P2224, exhibit weak production from E. coli. Interestingly, these scFv contain a fusion of lambda3 and lambda1 V-region (LV3 and LV1) genes, most likely the result of a PCR aberration during library construction. To enhance the biophysical properties of these scFvs, we utilized a structure-based approach to replace and redesign the pre-existing framework of the VL domain to one that best pairs with the existing VH. We describe a method to exchange lambda sequences with a more stable kappa3 framework (KV3) within the VL domain that incorporates the original lambda DE-loop. The resulting scFvs, C10KV3_LV1DE and P2224KV3_LV1DE, are more thermodynamically stable and easier to produce from bacterial culture. Additionally, C10KV3_LV1DE and P2224KV3_LV1DE retain binding affinity to EGFR, suggesting that such a dramatic framework swap does not significantly affect scFv binding. We provide here a novel strategy for redesigning the light chain of problematic scFvs to enhance their stability and therapeutic applicability.

  17. Solar sanitary system (SOL-SAN)

    Energy Technology Data Exchange (ETDEWEB)

    Cobb, J.C.

    1996-11-01

    Ordinary composting toilets, because of cooling by evaporation, do not heat the product (humus) hot enough to kill all pathogenic viruses, bacteria, or parasite eggs and cysts. The SOL-SAN system uses direct radiation to pasteurize incoming river water for drinking and also, separately, to pasteurize and dry the humus, and to pasteurize the effluent gray/brown water. Work is in progress on simple fool-proof methods of insuring that the water will not flow out unless it has been pasteurized. Heat exchangers recapture the heat from these very hot pasteurized liquids, thereby warming more in-coming water for washing, which is important for preventing transmission of pathogenic microbes. When pasteurized, the humus and gray/brown water can safely be recycled to fertilize and water the family vegetable garden. Thus no sewer would be needed, and the vegetables or fish would grow well. Widespread use of the SOL-SAN system would save water and nutrients, reduce the prevalence of infectious diseases, improve the nutrition and vitality of the population, and save the large fraction of human food now consumed by parasites.

  18. Sol-gel precursors and products thereof

    Science.gov (United States)

    Warren, Scott C.; DiSalvo, Jr., Francis J.; Weisner, Ulrich B.

    2017-02-14

    The present invention provides a generalizable single-source sol-gel precursor capable of introducing a wide range of functionalities to metal oxides such as silica. The sol-gel precursor facilitates a one-molecule, one-step approach to the synthesis of metal-silica hybrids with combinations of biological, catalytic, magnetic, and optical functionalities. The single-source precursor also provides a flexible route for simultaneously incorporating functional species of many different types. The ligands employed for functionalizing the metal oxides are derived from a library of amino acids, hydroxy acids, or peptides and a silicon alkoxide, allowing many biological functionalities to be built into silica hybrids. The ligands can coordinate with a wide range of metals via a carboxylic acid, thereby allowing direct incorporation of inorganic functionalities from across the periodic table. Using the single-source precursor a wide range of functionalized nanostructures such as monolith structures, mesostructures, multiple metal gradient mesostructures and Stober-type nanoparticles can be synthesized. ##STR00001##

  19. Sol-gel precursors and products thereof

    Energy Technology Data Exchange (ETDEWEB)

    Warren, Scott C.; DiSalvo, Jr., Francis J.; Weisner, Ulrich B.

    2017-02-14

    The present invention provides a generalizable single-source sol-gel precursor capable of introducing a wide range of functionalities to metal oxides such as silica. The sol-gel precursor facilitates a one-molecule, one-step approach to the synthesis of metal-silica hybrids with combinations of biological, catalytic, magnetic, and optical functionalities. The single-source precursor also provides a flexible route for simultaneously incorporating functional species of many different types. The ligands employed for functionalizing the metal oxides are derived from a library of amino acids, hydroxy acids, or peptides and a silicon alkoxide, allowing many biological functionalities to be built into silica hybrids. The ligands can coordinate with a wide range of metals via a carboxylic acid, thereby allowing direct incorporation of inorganic functionalities from across the periodic table. Using the single-source precursor a wide range of functionalized nanostructures such as monolith structures, mesostructures, multiple metal gradient mesostructures and Stober-type nanoparticles can be synthesized. ##STR00001##

  20. Analyses of laser and furnace treated sol-gel coatings

    NARCIS (Netherlands)

    De Hosson, JT; De Haas, M; Sudarshan, TS; Jeandin, M; Khor, KA

    1998-01-01

    Here we explore a new method that allows thin films to be made with almost any composition and degree of porosity by means of a combination of sol-gel and laser technology. Results are presented for furnace and laser treated TEOTI-(tetraethylorthotitanate as sol precursor) coated silicon samples.

  1. Self-Healing Corrosion Protective Sol-Gel Coatings

    NARCIS (Netherlands)

    Abdolah Zadeh, M.

    2016-01-01

    Inspired by the state of the art and the recent advances in the field of self-healing corrosion protective coatings, the thesis entitled “Self-healing corrosion protective sol-gel coatings” addresses novel routes to self-healing corrosion protective sol-gel coatings via extrinsic and intrinsic

  2. Analyses of laser and furnace treated sol-gel coatings

    NARCIS (Netherlands)

    De Hosson, JT; De Haas, M; Sudarshan, TS; Jeandin, M; Khor, KA

    1998-01-01

    Here we explore a new method that allows thin films to be made with almost any composition and degree of porosity by means of a combination of sol-gel and laser technology. Results are presented for furnace and laser treated TEOTI-(tetraethylorthotitanate as sol precursor) coated silicon samples. Fr

  3. Self-Healing Corrosion Protective Sol-Gel Coatings

    NARCIS (Netherlands)

    Abdolah Zadeh, M.

    2016-01-01

    Inspired by the state of the art and the recent advances in the field of self-healing corrosion protective coatings, the thesis entitled “Self-healing corrosion protective sol-gel coatings” addresses novel routes to self-healing corrosion protective sol-gel coatings via extrinsic and intrinsic heali

  4. Application of the docking program SOL for CSAR benchmark.

    Science.gov (United States)

    Sulimov, Alexey V; Kutov, Danil C; Oferkin, Igor V; Katkova, Ekaterina V; Sulimov, Vladimir B

    2013-08-26

    This paper is devoted to results obtained by the docking program SOL and the post-processing program DISCORE at the CSAR benchmark. SOL and DISCORE programs are described. SOL is the original docking program developed on the basis of the genetic algorithm, MMFF94 force field, rigid protein, precalculated energy grid including desolvation in the frame of simplified GB model, vdW, and electrostatic interactions and taking into account the ligand internal strain energy. An important SOL feature is the single- or multi-processor performance for up to hundreds of CPUs. DISCORE improves the binding energy scoring by the local energy optimization of the ligand docked pose and a simple linear regression on the base of available experimental data. The docking program SOL has demonstrated a good ability for correct ligand positioning in the active sites of the tested proteins in most cases of CSAR exercises. SOL and DISCORE have not demonstrated very exciting results on the protein-ligand binding free energy estimation. Nevertheless, for some target proteins, SOL and DISCORE were among the first in prediction of inhibition activity. Ways to improve SOL and DISCORE are discussed.

  5. Biocatalysis with Sol-Gel Encapsulated Acid Phosphatase

    Science.gov (United States)

    Kulkarni, Suhasini; Tran, Vu; Ho, Maggie K.-M.; Phan, Chieu; Chin, Elizabeth; Wemmer, Zeke; Sommerhalter, Monika

    2010-01-01

    This experiment was performed in an upper-level undergraduate biochemistry laboratory course. Students learned how to immobilize an enzyme in a sol-gel matrix and how to perform and evaluate enzyme-activity measurements. The enzyme acid phosphatase (APase) from wheat germ was encapsulated in sol-gel beads that were prepared from the precursor…

  6. Structural evolution of silica sols modified with formamide

    Directory of Open Access Journals (Sweden)

    Lenza R.F.S.

    2001-01-01

    Full Text Available In this work we investigated the influence of formamide on the acid-catalyzed sol-gel process by Fourier transform infrared spectroscopy (FTIR. Three silica sols were studied: Sol catalyzed with nitric acid without formamide, sol catalyzed with nitric acid containing formamide and sol catalyzed with a mixture of nitric acid and hydrofluoric acid and modified with formamide. Following the time evolution of both the Si-(OH stretching vibration at around 950 cm-1 and the Si-O-(Si vibration between 1040 cm-1 and 1200 cm-1 we were able to describe the structural evolution of each sol. The curve of evolution of Si-(OH stretching vibration corresponding to sol A has a simple asymptotic evolution. In the case of formamide containing sol, we observed a two-step structural evolution indicating that for the system containing formamide the polymerization goes through a temporary stabilization of oligomers, which can explain the non-variation of the Si-O(H bond wavenumber for a certain time. Gelation times were of several days for gels without formamide and few hours for gels containing additive. The presence of additive resulted in a highly interconnected gel.

  7. Spectroscopic studies of triethoxysilane sol-gel and coating process.

    Science.gov (United States)

    Li, Ying-Sing; Ba, Abdul

    2008-10-01

    Silica sol-gels have been prepared under different conditions using triethoxysilane (TES) as precursor. The prepared sol-gels have been used to coat aluminum for corrosion protection. Vibrational assignments have been made for most vibration bands of TES, TES sol-gel, TES sol-gel-coated aluminum and xerogel. It has been noticed that air moisture may have helped the hydrolysis of the thin coating films. Xerogels have been obtained from the sol-gel under different temperature conditions and the resulting samples have been characterized by using infrared and Raman spectroscopic methods. IR data indicate that the sol-gel process is incomplete under the ambient conditions although an aqueous condition can have slightly improved the process. Two nonequivalent silicon atoms have been identified from the collected 29Si NMR spectra for the sol-gel, supporting the result derived from the IR data. The frequency of Si-H bending vibration has been found to be more sensitive to the skeletal structure than that of the Si-H stretching vibration. A higher temperature condition could favor the progression of hydrolysis and condensation. A temperature higher than 300 degrees C would cause sample decomposition without seriously damaging the silica network. From infrared intensity measurements and thermo-gravimetric analyses, the fractions of incomplete hydrolysis and condensation species have been estimated to be 4% and 3%, respectively. Electrochemical data have shown that the sol-gel coating significantly improves the corrosion protection properties of aluminum.

  8. Redirecting Specificity of T cells Using the Sleeping Beauty System to Express Chimeric Antigen Receptors by Mix-and-Matching of VL and VH Domains Targeting CD123+ Tumors.

    Science.gov (United States)

    Thokala, Radhika; Olivares, Simon; Mi, Tiejuan; Maiti, Sourindra; Deniger, Drew; Huls, Helen; Torikai, Hiroki; Singh, Harjeet; Champlin, Richard E; Laskowski, Tamara; McNamara, George; Cooper, Laurence J N

    2016-01-01

    Adoptive immunotherapy infusing T cells with engineered specificity for CD19 expressed on B- cell malignancies is generating enthusiasm to extend this approach to other hematological malignancies, such as acute myelogenous leukemia (AML). CD123, or interleukin 3 receptor alpha, is overexpressed on most AML and some lymphoid malignancies, such as acute lymphocytic leukemia (ALL), and has been an effective target for T cells expressing chimeric antigen receptors (CARs). The prototypical CAR encodes a VH and VL from one monoclonal antibody (mAb), coupled to a transmembrane domain and one or more cytoplasmic signaling domains. Previous studies showed that treatment of an experimental AML model with CD123-specific CAR T cells was therapeutic, but at the cost of impaired myelopoiesis, highlighting the need for systems to define the antigen threshold for CAR recognition. Here, we show that CARs can be engineered using VH and VL chains derived from different CD123-specific mAbs to generate a panel of CAR+ T cells. While all CARs exhibited specificity to CD123, one VH and VL combination had reduced lysis of normal hematopoietic stem cells. This CAR's in vivo anti-tumor activity was similar whether signaling occurred via chimeric CD28 or CD137, prolonging survival in both AML and ALL models. Co-expression of inducible caspase 9 eliminated CAR+ T cells. These data help support the use of CD123-specific CARs for treatment of CD123+ hematologic malignancies.

  9. Redirecting Specificity of T cells Using the Sleeping Beauty System to Express Chimeric Antigen Receptors by Mix-and-Matching of VL and VH Domains Targeting CD123+ Tumors

    Science.gov (United States)

    Olivares, Simon; Mi, Tiejuan; Maiti, Sourindra; Deniger, Drew; Huls, Helen; Torikai, Hiroki; Singh, Harjeet; Champlin, Richard E.; Laskowski, Tamara; McNamara, George; Cooper, Laurence J. N.

    2016-01-01

    Adoptive immunotherapy infusing T cells with engineered specificity for CD19 expressed on B- cell malignancies is generating enthusiasm to extend this approach to other hematological malignancies, such as acute myelogenous leukemia (AML). CD123, or interleukin 3 receptor alpha, is overexpressed on most AML and some lymphoid malignancies, such as acute lymphocytic leukemia (ALL), and has been an effective target for T cells expressing chimeric antigen receptors (CARs). The prototypical CAR encodes a VH and VL from one monoclonal antibody (mAb), coupled to a transmembrane domain and one or more cytoplasmic signaling domains. Previous studies showed that treatment of an experimental AML model with CD123-specific CAR T cells was therapeutic, but at the cost of impaired myelopoiesis, highlighting the need for systems to define the antigen threshold for CAR recognition. Here, we show that CARs can be engineered using VH and VL chains derived from different CD123-specific mAbs to generate a panel of CAR+ T cells. While all CARs exhibited specificity to CD123, one VH and VL combination had reduced lysis of normal hematopoietic stem cells. This CAR’s in vivo anti-tumor activity was similar whether signaling occurred via chimeric CD28 or CD137, prolonging survival in both AML and ALL models. Co-expression of inducible caspase 9 eliminated CAR+ T cells. These data help support the use of CD123-specific CARs for treatment of CD123+ hematologic malignancies. PMID:27548616

  10. Applying VM to Evaluate the City Buildings of China%用VM的观点看中国的城市建筑

    Institute of Scientific and Technical Information of China (English)

    李岩; 李素蕾

    2006-01-01

    改革开放以来,中国的各大城市与若干年前相比发生了天翻地覆的变化.贪大、求洋、求新、超越实际经济承受能力的城市建筑正在中国大张旗鼓的上演.目前,我国是一个资源浪费大国,面临严重的能源危机.但还有很多城市在超越经济承受能力的情况下大搞城镇建设.本文用VM(Value Management)的观点分析这一现象.

  11. Optical and electrochemical sol-gel sensors for inorganic species

    Institute of Scientific and Technical Information of China (English)

    Royce; N.DANSBY-SPARKS

    2009-01-01

    The use of sol-gels as a sensing matrix for the development of unique sensing strategies is discussed.Sol-gels offer almost limitless possibilities for sensing substrates due to the variety of physical properties that can be obtained by altering a number of discussed fabrication conditions and techniques.By careful consideration of the sensing requirements,novel detection methods have been developed for a variety of analytes and applications.Here,sol-gels have been used to monitor pH at the extreme ends of the scale([H+] = 1―11 M and [OH-] = 1―10 M) and in mixed solvent/solute systems using dual sensing approaches.The use of ligand-grafted sol-gel monoliths for optical determination of metal ion species is also discussed.The electrochemical determination of Cr(Ⅵ) by electrodeposited sol-gel modified electrodes is also presented.

  12. Optical and electrochemical sol-gel sensors for inorganic species

    Institute of Scientific and Technical Information of China (English)

    Royce N.DANSBY-SPARKS; OUYANG RuiZhuo; XUE ZiLing

    2009-01-01

    The use of sol-gels as a sensing matrix for the development of unique sensing strategies is discussed.Sol-gels offer almost limitless possibilities for sensing substrates due to the variety of physical properties that can be obtained by altering a number of discussed fabrication conditions and techniques.By careful consideration of the sensing requirements,novel detection methods have been developed for a variety of analytes and applications.Here,sol-gels have been used to monitor pH at the extreme ends of the scale ([H~+]=1-11 M and[OH~-]=1-10 M) and in mixed solvent/solute systems using dual sensing approaches.The use of ligand-grafted sol-gel monoliths for optical determination of metal ion species is also discussed.The electrochemical determination of Cr(Ⅵ) by electrodeposited sol-gel modified electrodes is also presented.

  13. APPLICATION OF BORON MODIFIED SILICA SOL ON RETENTION AND DRAINAGE

    Institute of Scientific and Technical Information of China (English)

    JinxiaMa; YuxiuPeng; ZhongzhengLi

    2004-01-01

    In this paper it was studied that these dosage effectsof CPAM, cationic starch,boron modified silica sol(BMS), A12(SO4)3, pH value and electrolyte on theretention and drainage of different microparticulatesystems including CPAM, cationic starch and boronsilica sol. The research results indicated that CPAMhad no good retention when used with boron silicasol. The best retention efficiency was the micropar-ticulate system of CPAM + cationic starch withboron modified silica sol; Secondly was that ofcationic starch with boron modified silica sol; Theworst was that of CPAM with boron modified silicasol. The retention efficiency had no relation with theaddition order between CPAM and cationic starch. Itwas also found that the microparticulate retentionsystem of boron modified silica sol could be used inalum-rosin sizing and in acidity, neutral or alkalinepapermaking conditions. This system also could beused with close circulate water so that it could reducethe water pollution and waste.

  14. Time for a Change; Spirit's View on Sol 1843

    Science.gov (United States)

    2009-01-01

    NASA's Mars Exploration Rover Spirit used its navigation camera to take the images that have been combined into this full-circle view of the rover's surroundings during the 1,843rd Martian day, or sol, of Spirit's surface mission (March 10, 2009). South is in the middle. North is at both ends. The rover had driven 36 centimeters downhill earlier on Sol 1854, but had not been able to get free of ruts in soft material that had become an obstacle to getting around the northeastern corner of the low plateau called 'Home Plate.' The Sol 1854 drive, following two others in the preceding four sols that also achieved little progress in the soft ground, prompted the rover team to switch to a plan of getting around Home Plate counterclockwise, instead of clockwise. The drive direction in subsequent sols was westward past the northern edge of Home Plate. This view is presented as a cylindrical projection with geometric seam correction.

  15. Time for a Change; Spirit's View on Sol 1843

    Science.gov (United States)

    2009-01-01

    NASA's Mars Exploration Rover Spirit used its navigation camera to take the images that have been combined into this full-circle view of the rover's surroundings during the 1,843rd Martian day, or sol, of Spirit's surface mission (March 10, 2009). South is in the middle. North is at both ends. The rover had driven 36 centimeters downhill earlier on Sol 1854, but had not been able to get free of ruts in soft material that had become an obstacle to getting around the northeastern corner of the low plateau called 'Home Plate.' The Sol 1854 drive, following two others in the preceding four sols that also achieved little progress in the soft ground, prompted the rover team to switch to a plan of getting around Home Plate counterclockwise, instead of clockwise. The drive direction in subsequent sols was westward past the northern edge of Home Plate. This view is presented as a cylindrical projection with geometric seam correction.

  16. The Kv1.3 channel blocker Vm24 enhances muscle glucose transporter 4 mobilization but does not reduce body-weight gain in diet-induced obese male rats.

    Science.gov (United States)

    Jaimes-Hoy, Lorraine; Gurrola, Georgina B; Cisneros, Miguel; Joseph-Bravo, Patricia; Possani, Lourival D; Charli, Jean-Louis

    2017-07-15

    Voltage-gated potassium channels 1.3 (Kv1.3) can be targeted to reduce diet-induced obesity and insulin resistance in mice. Since species-specific differences in Kv1.3 expression and pharmacology have been observed, we tested the effect of Vm24, a high-affinity specific blocker of Kv1.3 channels from Vaejovis mexicanus smithi, on body weight (BW), glucose tolerance and insulin resistance in diet-induced obese rats. Young adult male Wistar rats were switched to a high-fat/high-fructose (HFF) diet. Eighteen days later animals were divided in two groups: vehicle and Vm24 group. Subcutaneous injections were applied every other day until sacrifice 2months later. An additional cohort was maintained on standard chow. The HFF diet promoted obesity. Treatment with Vm24 did not alter various metabolic parameters such as food intake, BW gain, visceral white adipose tissue mass, adipocyte diameter, serum glucose, leptin and thyroid hormone concentrations, brown adipose tissue mass or uncoupling protein-1 expression, and insulin tolerance. Vm24 did reduce basal and glucose-stimulated serum insulin concentrations, serum C-peptide concentration, increased QUICKI, and tended to lower HOMA-IR. Vm24 treatment did not change the activation of insulin receptor substrate-1, but enhanced protein-kinase B activation and membrane glucose-transporter 4 (GLUT4) protein levels in skeletal muscle. In conclusion, in male rats, long-term blockade of Kv1.3 channels with Vm24 does not reduce weight gain and visceral adiposity induced by HFF diet; instead, it reduces serum insulin concentration, and enhances GLUT4 mobilization in skeletal muscle. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. Optimal hysteretic control for a B M A P / S M / 1 / N queue with two operation modes

    Directory of Open Access Journals (Sweden)

    Dudin Alexander N.

    1999-01-01

    Full Text Available We consider B M A P / S M / 1 type queueing system with finite buffer of size N . The system has two operation modes, which are characterized by the matrix generating function of B M A P -input, the kernel of the semi-Markovian service process, and utilization cost. An algorithm for determining the optimal hysteresis strategy is presented.

  18. Rover Panorama from Sols 75 & 76

    Science.gov (United States)

    1998-01-01

    This Sojourner rover panorama from Sols 75 and 76 is the only true panorama product (as opposed to the normal 'tiled' full frames) produced by the rover. This panorama ranges from Big Crater on the left (about azimuth 160 degrees), past the Twin Peaks and almost all the way to the north horizon, for a swath of about 200 degrees in azimuth.Mars Pathfinder is the second in NASA's Discovery program of low-cost spacecraft with highly focused science goals. The Jet Propulsion Laboratory, Pasadena, CA, developed and manages the Mars Pathfinder mission for NASA's Office of Space Science, Washington, D.C. JPL is a division of the California Institute of Technology (Caltech).

  19. Phoenix Telltale Movie with Clouds, Sol 103

    Science.gov (United States)

    2008-01-01

    NASA's Phoenix Mars Lander's telltale catches a breeze as clouds move over the landing site on Sol 103 (Sept. 7, 2008), the 103rd Martian day since landing. Phoenix's Surface Stereo Imager took this series of images during daily telltale monitoring around 3 p.m. local solar time and captured the clouds moving over the landing site. Phoenix can measure wind speed and direction by imaging the telltale, which is about about 10 centimeters (4 inches) tall. The telltale was built by the University of Aarhus, Denmark. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  20. Edificio Playa, en la Costa del Sol

    Directory of Open Access Journals (Sweden)

    Cassinello, Fernando

    1964-02-01

    Full Text Available This apartment block has been built on the Costa del Sol, in Almeria, only a few metres from the seashore. It is meant to provide the following facilities. Changing rooms for bathers, and a night club, in the basement. Restaurant and bar on the ground floor. Twelve living apartments on the six standard floor levels; two apartments per storey. Porter's house in the attic. As the foundations are in the sand, and the building is exposed to strong coastal winds, the structural design has, as interesting features, the foundation ribbed slab and the transversal portal frames, which are W shaped on the ground level. This arrangement makes the edifice look lighter and it acquires a more dynamic plasticity.En la Costa del Sol de Almería y a muy pocos metros de la orilla del mar, se ha construido este edificio de apartamentos. Su programa es el siguiente: casetas de baño y sala de fiestas, en sótano; restaurante-bar, en planta baja; doce viviendas, en las seis plantas tipo, con dos viviendas por planta; y vivienda del portero en ático. Cimentado sobre arena y expuesto a los fuertes vientos que azotan la costa, la solución estructural ofrece el interés de su tipo de cimentación por placa nervada, y de sus pórticos transversales que en planta baja adoptan forma de W, con lo que el edificio adquiere un aspecto de mayor ligereza y de dinamismo plástico.

  1. APPLICATION OF BORON MODIFIED SILICA SOL ON RETENTION AND DRAINAGE

    Institute of Scientific and Technical Information of China (English)

    Jinxia Ma; Yuxiu Peng; Zhongzheng Li

    2004-01-01

    In this paper it was studied that these dosage effects of CPAM, cationic starch、boron modified silica sol (BMS), Al2(SO4)3, pH value and electrolyte on the retention and drainage of different microparticulate systems including CPAM, cationic starch and boron silica sol. The research results indicated that CPAM had no good retention when used with boron silica sol. The best retention efficiency was the microparticulate system of CPAM + cationic starch with boron modified silica sol; Secondly was that of cationic starch with boron modified silica sol; The worst was that of CPAM with boron modified silica sol. The retention efficiency had no relation with the addition order between CPAM and cationic starch. It was also found that the microparticulate retention system of boron modified silica sol could be used in alum-rosin sizing and in acidity, neutral or alkaline papermaking conditions. This system also could be used with close circulate water so that it could reduce the water pollution and waste.

  2. Modified silica sol coatings for surface enhancement of leather.

    Science.gov (United States)

    Mahltig, Boris; Vossebein, Lutz; Ehrmann, Andrea; Cheval, Nicolas; Fahmi, Amir

    2012-06-01

    The presented study reports on differently modified silica sols for coating applications on leather. Silica sols are prepared by acidic hydrolysis of tetraethoxysilane and modified by silane compounds with fluorinated and non-fluorinated alkylgroups. In contrast to many earlier investigations regarding sol-gel applications on leather, no acrylic resin is used together with the silica sols when applying on leather. The modified silica particles are supposed to aggregate after application, forming thus a modified silica coating on the leather substrate. Scanning electron microscopy investigation shows that the applied silica coatings do not fill up or close the pores of the leather substrate. However, even if the pores of the leather are not sealed by this sol-gel coating, an improvement of the water repellent and oil repellent properties of the leather substrates are observed. These improved properties of leather by application of modified silica sols can provide the opportunity to develop sol-gel products for leather materials present in daily life.

  3. Sol, Tierra y Luna. Movimientos relativos y sus consecuencias

    Directory of Open Access Journals (Sweden)

    Sebastián Cardenete García

    2011-01-01

    Full Text Available Cuando se pregunta a los estudiantes por la causa de las estaciones suelen responder: "en verano estamos más próximos al Sol y en invierno estamos más lejos del Sol". La persistencia de esta idea y el hecho de su generalización entre los estudiantes y muchos adultos me ha inducido a escribir este artículo, en el cual se trata de explicar, de una forma clara y simple, el motivo de este y otros fenómenos debidos al movimiento de la Luna alrededor de la Tierra y de ésta alrededor del Sol.

  4. Effect of Chelating Agents on the Stability of Nano-TiO2 Sol Particles for Sol-Gel Coating.

    Science.gov (United States)

    Maeng, Wan Young; Yoo, Mi

    2015-11-01

    Agglomeration of sol particles in a titanium alkoxide (tetrabutyl orthotitanate (TBOT), > 97%) solution during the hydrolysis and condensation steps makes the sol solution difficult to use for synthesizing homogeneous sol-gel coating. Here, we have investigated the effect of stabilizing agents (acetic acid and ethyl acetoacetate (EAcAc)) on the agglomeration of Ti alkoxide particles during hydrolysis and condensation in order to determine the optimized conditions for controlling the precipitation of TiO2 particles. The study was conducted at R(AC) ([acetic acid]/[TBOT]) = 0.1-5 and R(EAcAc)([EAcAc]/[TBOT]) = 0.05-0.65. We also studied the effects of a basic catalyst ethanolamine (ETA), water, and HCl on sol stability. The chelating ligands in the precursor sol were analyzed with FT-IR. The coating properties were examined by focused ion beam. The stabilizing agents (acetic acid and EAcAc) significantly influenced the agglomeration and precipitation of TBOT precursor particles during hydrolysis. As R(AC) and R(EAcAc) increased, the agglomeration remarkably decreased. The stability of the sol with acetic acid and EAcAc arises from the coordination of the chelating ligand to TBOT that hinders hydrolysis and condensation. A uniform fine coating (thickness: 30 nm) on stainless steel was obtained by using an optimized sol with R(AC) = 0.5 and R(EAcAc) = 0.65.

  5. MicroRNA-181b提高U87细胞对VM-26的敏感性研究%miR-181b Enhances Sensitivity to Teniposide in Glioma Cell Line U87

    Institute of Scientific and Technical Information of China (English)

    孙衍昶; 郭琤琤; 赛克; 王翦; 王洁; 陈芙蓉; 张宗平; 陈忠平

    2013-01-01

    背景与目的:MicroRNA(miRNA)参与肿瘤发生发展的诸多过程,并参与调节多种抗肿瘤药物的敏感性.本研究探讨恶性胶质瘤中miR-181b对VM-26(teniposide)化疗敏感性的影响.方法:以荧光定量PCR法检测miR-181b在高级别胶质瘤中的表达,并利用CCK-8细胞毒性实验检测高级别胶质瘤患者细胞对VM-26的化疗敏感性;并通过慢病毒感染构建稳定高表达miR-181b的U87/181b细胞及其对照组U87/nc,在荧光显微镜下观察其转染率及荧光定量PCR法检测其中miR-181b的表达;进而利用CCK-8细胞毒性实验检测U87/181b和U87/nc细胞对VM-26的敏感性,利用流式细胞仪检测VM-26作用72小时后U87/181b和U87/nc的凋亡情况.结果:在高级别胶质瘤中,miR-181b的表达与VM-26的敏感性呈正相关(r=-0.691,P< 0.01),也就是miR-181b高表达肿瘤对VM-26的敏感性高.qPCR检测miR-181b在U87/181b (0.699±0.023)的表达显著高于U87/nc(0.019±0.001) (P< 0.05).CCK-8检测结果显示U87/181b [IC50:(1.25±0.12)μg/mL]对VM-26的敏感性显著高于U87/nc[IC50:(6.24±0.88) μg/mL] (P< 0.05).经VM-26处理后U87/181b凋亡率(69.41±0.77)明显高于U87/nc(37.93±2.90)(P< 0.05).结论:在高级别胶质瘤高表达miR-181b的肿瘤对VM-26的敏感性高;在胶质瘤细胞U87中增加miR-181b表达可以提高对VM-26的敏感性.

  6. Sol-gel materials for optofluidics - process and applications

    DEFF Research Database (Denmark)

    Mikkelsen, Morten Bo Lindholm

    2011-01-01

    This Ph.D. thesis is concerned with the use of sol-gel materials in optofluidic applications and the physics of DNA molecules in nanoconfinement. The bottom-up formation of solid material, which is provided by the sol-gel process, enables control of the chemical composition and porosity...... of the material. At early stages of gelation, thin gel coatings can be structured by nanoimprint lithography, and purely inorganic silica materials can be obtained by subsequent thermal annealing. The sol-gel process thus constitutes a unique method for nanofabrication of silica materials of special properties....... In this work, sol-gel silica is introduced as a new material class for the fabrication of lab-on-a-chip devices for DNA analysis. An imprint process with a rigid, non-permeable stamp was developed, which enabled fabrication of micro- and nanofluidic silica channels in a single process step without use of any...

  7. Fast temperature fluctuation measurements in SOL of tokamak TCV

    DEFF Research Database (Denmark)

    Horacek, J.; Nielsen, Anders Henry; Pitts, R.A.

    coupling both across the plasma sheath and in the probe circuit itself. Comparisons are also made between the results from higher frequency sweeping and the standard values derived from a slower sweep to show that the fast measurement is reliable. Considerable effort has been expended in recent years...... to compare the statistical character of turbulence in the SOL particle flux on TCV with results from the 2D fluid electrostatic model ESEL [2][4]. Using results from the fast sweeping, similar comparisons can now be made with the fluctuating Te and will be described in this contribution. We also present...... distribution function, introduced for SOL turbulence in [5]. The fast Te capability also allows the SOL response to Edge Localised Modes (ELMs) to be studied and new results will be presented for the far SOL Te response during Type III ELMs....

  8. Sol-Gel/Hydrothermal Synthesis of Mixed Metal Oxide

    African Journals Online (AJOL)

    Mixed metal oxides of titanium and zinc nanocomposites were prepared through sol-gel method under hydrothermal ... the production of TiO -ZnO nanoparticles use. 2 either titanium ... involved using titanium sulphate and thioacetamide for ...

  9. Application of Vacuum Drying to Silica Sol Ceramic Mold

    Institute of Scientific and Technical Information of China (English)

    Ming ZENG; Xinqiang YUAN; Baoluo SHEN; Yunqiu ZHENG

    2008-01-01

    Silica sol ceramic mold was made at room temperature with JN-30 silica sol, silica powder and NH4Cl. It is found that the harden time of silica sol ceramic mold is only 0.5 to 1.5 h under the amount of NH4CI solution of 7% to 8% with 15% concentration, and less surface cracks occur by using vacuum drying. The proper vacuum drying process parameters: vacuum drying temperature is 80 to 100℃, drying time is 5 h and vacuum is 0.06 to 0.07 MPa. The harden mechanics, vacuum drying mechanics and the reason of less surface cracks of silica sol ceramic mold by vacuum drying were also analyzed in this paper.

  10. Production of continuous mullite fiber via sol-gel processing

    Science.gov (United States)

    Tucker, Dennis S.; Sparks, J. Scott; Esker, David C.

    1990-01-01

    The development of a continuous ceramic fiber which could be used in rocket engine and rocket boosters applications was investigated at the Marshall Space Flight Center. Methods of ceramic fiber production such as melt spinning, chemical vapor deposition, and precursor polymeric fiber decomposition are discussed and compared with sol-gel processing. The production of ceramics via the sol-gel method consists of two steps, hydrolysis and polycondensation, to form the preceramic, followed by consolidation into the glass or ceramic structure. The advantages of the sol-gel method include better homogeneity and purity, lower preparation temperature, and the ability to form unique compositions. The disadvantages are the high cost of raw materials, large shrinkage during drying and firing which can lead to cracks, and long processing times. Preparation procedures for aluminosilicate sol-gel and for continuous mullite fibers are described.

  11. Soluble polymers in sol-gel silica

    Science.gov (United States)

    Beaudry, Christopher Laurent

    In the last few years, the inherent versatility of sol-gel processing has led to a significant research effort on inorganic/organic materials. One method of incorporating an organic phase into sol-gel silica is dissolving an organic polymer in a tetraethylorthosilicate (TEOS) solution, followed by in situ polymerization of silica in the presence of organic polymer. The first part of the study involved the development of a two-step (acid-base) synthesis procedure to allow systematic control of acidity in TEOS solutions. With this procedure, it was possible to increase the pH of the TEOS solution while correlating the acidity and properties. The properties were the gelation time, syneresis rate, drying behavior, and xerogel pore structure, as determined by nitrogen sorption. Furthermore, controlling the acidity was shown to control the silica xerogel pore structure. In the second part of the study, the two-step procedure was used to synthesize silica/poly(ethylene glycol) (PEG), and silica/poly(vinyl acetate) (PVAc) composite materials. The content of organic polymer and the molecular weight were varied. The gelation time, the syneresis rate, the drying behavior, and the pore structure were determined for compositions with 10% PEG (M.W. 2,000), 5, 10, and 15% PEG (M.W. 3,400), and 10 and 25% PVAc (M.W. 83,000). Other compositions and molecular weights of PEG lead to sedimentation. In the PEG compositions, the tendency to phase separate was correlated with the effects of the processing variables on the segregation strength and polymerization rate. The PVAc compositions did not show any visible phase separation during processing, giving the composite xerogels an appearance similar to pure silica. The property differences between gels with PEG and gels with PVAc show the relative strength of the interactions with silica. Both polymers exhibit hydrogen bonding between the phases. In the case of PEG, hydrogen bonding between the ether oxygens of the polymer and silanol

  12. Self-Healing Corrosion Protective Sol-Gel Coatings

    OpenAIRE

    Abdolah Zadeh, M.

    2016-01-01

    Inspired by the state of the art and the recent advances in the field of self-healing corrosion protective coatings, the thesis entitled “Self-healing corrosion protective sol-gel coatings” addresses novel routes to self-healing corrosion protective sol-gel coatings via extrinsic and intrinsic healing approaches. The employed approaches aim at extending the service life of the coating and the underlying substrate by multiple damage closure/sealing and metal surface protection through incorpor...

  13. Chemical Sensors Based on Molecularly Imprinted Sol-Gel Materials

    OpenAIRE

    Dickert, Franz L.; Lieberzeit, Peter A.; Adnan Mujahid

    2010-01-01

    The sol-gel technique is earning the worldwide attention of researchers in the field of material science, due to its versatility in synthesizing inorganic ceramic materials at mild conditions. High purity, homogeneity, controlled porosity, stable temperature and nanoscale structuring are the most remarkable features offered by this method for generating highly sensitive and selective matrices to incorporate analyte molecules. The crafting of sol-gel sensors through molecular imprinting has pu...

  14. Electrochemical and spectroscopic characterization of surface sol-gel processes.

    Science.gov (United States)

    Chen, Xiaohong; Wilson, George S

    2004-09-28

    (3-Mercaptopropyl)trimethoxysilane (MTS) forms a unique film on a platinum substrate by self-assembly and sol-gel cross-linking. The gelating and drying states of the self-assembled MTS sol-gel films were probed by use of electrochemical and spectroscopic methods. The thiol moiety was the only active group within the sol-gel network. Gold nanoparticles were employed to detect the availability of the thiol group and their interaction further indicated the physicochemical states of the sol-gel inner structure. It was found that the thiol groups in the open porous MTS aerogel matrix were accessible to the gold nanoparticles while thiol groups in the compact MTS xerogel network were not accessible to the gold nanoparticles. The characteristics of the sol-gel matrix change with time because of its own irreversible gelating and drying process. The present work provides direct evidence of gold nanoparticle binding with thiol groups within the sol-gel structures and explains the different permeability of "aerogel" and "xerogel" films of MTS on the basis of electrochemical and spectroscopic results. Two endogenous species, hydrogen peroxide and ascorbic acid, were used to test the permeability of the self-assembled sol-gel film in different states. The MTS xerogel film on the platinum electrode was extremely selective against ascorbic acid while maintaining high sensitivity to hydrogen peroxide in contrast to the relatively high permeability of ascorbic acid in the MTS aerogel film. This study showed the potential of the MTS sol-gel film as a nanoporous material in biosensor development.

  15. SolSTUS: Solar Source Thermal Upper Stage

    OpenAIRE

    1994-01-01

    During the past academic year the members of Utah State University's Space Systems Design class have worked on the design of SolSTUS (Solar Source Thermal Upper Stage), a solar propulsion system that could be carried into low earth orbit by small launch vehicles and still carry useful payloads into higher energy orbits or interplanetary missions. To demonstrate the capabilities of the SolSTUS the class worked to meet the requirements of a specific design reference mission. The reference missi...

  16. Composite sol-gel coatings on steel for tribological applications

    OpenAIRE

    Hermange, Kurt

    2016-01-01

    This thesis focuses on the elaboration and the characterization of composite sol-gel coatings “CSG” on austenitic stainless steelAISI 304. The aim of the thesis is to develop the process and to study the mechanical properties and tribological behavior of thecoatings. The first experimental part presents the optimization of the synthesis conditions of a stable alumina sol and the influence of the thermal treatment of the gel on the physic-chemical and thermostructural properties. The studied p...

  17. 基于LabVlEW的FSAE赛车动态性能测试系统%Design of FSAE Race Dynamic Performance Test System Based on LabVIEW

    Institute of Scientific and Technical Information of China (English)

    董瑞佳; 汪国民

    2011-01-01

    介绍了基于图形语言LabVlEW和无线传输的FSAE赛车动态性能测试系统,重点讲解电气和程序控制部分的开发和设计.该系统利用了无线传输系统和计算机串口,可实现FSAE赛车75米直线加速和绕8字等动态性能测试与实时监控,该系统具有较高的测试精度与可靠性.

  18. Primary exploration of the efficiency of VM26 combined with MeCCNU therapy for the low-grade gliomas%VM26联合MeCCNU在人脑低级别胶质瘤治疗中应用的初步探讨

    Institute of Scientific and Technical Information of China (English)

    曹广辉; 谭卫国; 冯鸣; 申昊; 王君祥; 黄煜伦; 周幽心

    2011-01-01

    Objective To explore the efficiency of VM26 combined with MeCCNU therapy for the low-grade gliomas of MCMT-positive after tumor resection and radiotherapy. Methods The clinical data of 22 patients with MCMT-positive who underwent total removal of tumors with enhanced MRI imaging showing no residual tumors from Jan 2005 to Oct 2008 in our department were analyzed retrospectively. Of 22 patients . 10 were diffuse astrocytomas; 3 were oligodendrogliomas;5 were are mixed oligo-astrocytomas and 4 ependymomas. These patients received three-dimensional conformal radiotherapy 2 -4 weeks after surgery with radiation and exposure dose being ( 50~ 55 ) Gy( 6 ~ 7 )weeks. 2 weeks after the end of radiotherapy , these patients underwent VM26 comhined with MeCCNU therapy ( VM26 : 50mg/m2/day , intravenous dripping for 3 days , repeated after 8 weeks for 3 cycles.MeCCNU: 50mg/m2/day, taken orally for 3 days, repeated after 8 weeks for 4 cycles) with MRI scanning regularly. Results Of 22 MCMT-positive grade Ⅱ gliomas,6 cases were positive for both TopoⅡα and Pgp,10 and 2 were only positive for TopoⅡα and Pgp, respectively; and 4 were negative for both TopoⅡα and Pgp. The following up from 2 t0 5 years showed tumors recurred in 6 cases with average time of recurrence being 16. 6 months ,CT or MRI imaging showed no tumor recurrence in 13 ,3 underwent the second surgery due to MRI imaging showing possible tumor recurrence 2 vears after prior surgery. Pathological examination reported suspected recurring tumor was necrotic tissue. In these 22 patients , one vear survival rate of one vear was 100% and two vears was 88.9% . Conclusions VM26 combined with MeCCNU chemotherapy is able to efficaciously inhibit the growth of gliomas ,with little side-effects.safety. It's an therapeutic method for patients with low-grade MGMT-positive gliomas aftert tumor resection and radiotherapy.%目的 探讨人脑胶质瘤手术切除和放疗后O6-甲基鸟嘌呤DNA甲基转移酶(MGMT

  19. Sol-gel-based biosensing applied to medicinal science.

    Science.gov (United States)

    Moreira, Felismina T C; Moreira-Tavares, Ana P; Sales, M Goreti F

    2015-01-01

    Biosensors have opened new horizons in biomedical analysis, by ensuring increased assay speed and flexibility, and allowing point-of-care applications, multi-target analyses, automation and reduced costs of testing. This has been a result of many studies merging nanotechnology with biochemistry over the years, thereby enabling the creation of more suitable environments to biological receptors and their substitution by synthetic analogue materials. Sol-gel chemistry, among other materials, is deeply involved in this process. Sol-gel processing allows the immobilization of organic molecules, biomacromolecules and cells maintaining their properties and activities, permitting their integration into different transduction devices, of electrochemical or optical nature, for single or multiple analyses. Sol-gel also allows to the production of synthetic materials mimicking the activity of natural receptors, while bringing advantages, mostly in terms of cost and stability. Moreover, the biocompatibility of sol-gel materials structures of biological nature allowed the use of these materials in emerging in vivo applications. In this chapter, biosensors for biomedical applications based on sol-gel derived composites are presented, compared and described, along with current emerging applications in vivo, concerning drug delivery or biomaterials. Sol-gel materials are shown as a promising tool for current, emerging and future medical applications.

  20. New Record Five-Wheel Drive, Spirit's Sol 1856

    Science.gov (United States)

    2009-01-01

    NASA's Mars Exploration Rover Spirit used its navigation camera to take the images that have been combined into this stereo, 180-degree view of the rover's surroundings during the 1,856th Martian day, or sol, of Spirit's surface mission (March 23, 2009). The center of the view is toward the west-southwest. The rover had driven 25.82 meters (84.7 feet) west-northwestward earlier on Sol 1856. This is the longest drive on Mars so far by a rover using only five wheels. Spirit lost the use of its right-front wheel in March 2006. Before Sol 1856, the farthest Spirit had covered in a single sol's five-wheel drive was 24.83 meters (81.5 feet), on Sol 1363 (Nov. 3, 2007). The Sol 1856 drive made progress on a route planned for taking Spirit around the western side of the low plateau called 'Home Plate.' A portion of the northwestern edge of Home Plate is prominent in the left quarter of this image, toward the south. This view is presented as a cylindrical projection with geometric seam correction.

  1. Texto e imagen en España de sol a sol de Alfonso Armada

    Directory of Open Access Journals (Sweden)

    Champeau, Geneviève

    2011-06-01

    Full Text Available España de sol a sol (2001 by Alfonso Armada gives an example of the development of the «travel narrative» genre in Spain today. Faced with the «end of travel» (Marc Augé, he proposes a renovation of the perception of the familiar by travelling across Spain and Portugal and by substituting «endotic» (Georges Pérec for exotic.The poetics in the narrative differs greatly from that by travelling writers of «social realism», in the Spain of the sixties. Interpretation replaces information, the poetic image prevails over the referential function of language, and polysemy, omnipresent intertexuality and metatextuality play an important part. The change also affects the links between text and image, which are now more complementary than redundant. Playing with stereotypes, the photography actively contributes to establishing argumentative strategies meant to make the reader-viewer adhere to the message, all while affirming itself as an autonomous aesthetic experience.España de sol a sol (2001 de Alfonso Armada proporciona una muestra de la evolución del género del «libro de viajes» en la España contemporánea. Ante la imposibilidad del viaje (Marc Augé, propone renovar la percepción de lo familiar recorriendo el espacio nacional y sustituyendo el «endotismo» (Georges Pérec al exotismo. La poética del viaje que propone el relato difiere profundamente de la de los escritores viajeros del «realismo social», en la España de los años sesenta, anteponiendo la interpretación a la información, la imagen poética a la función referencial del lenguaje, cultivando la polisemia, una intertextualidad masiva y una reflexión metatextual. Distintos son también los vínculos que se establecen entre texto e imagen, de complementariedad más que de redundancia. La fotografía participa activamente, por la reelaboración de tópicos, del dispositivo argumentativo destinado a favorecer la adhesión del lector-espectador al mensaje y se afirma

  2. Lambing Interval in Jezersko-Solčava and Improved Jezersko-Solčava Breed

    Directory of Open Access Journals (Sweden)

    Andreja Komprej

    2011-12-01

    Full Text Available The effects on lambing interval (LI in Improved Jezersko-Solčava (IJS breed were studied. Due to the reason that IJS breed originates from Jezersko-Solčava (JS breed, both breeds were included into the analysis. The data were obtained from the Republic Data Base for Selection of Small Ruminants, between 1993 and 2008. The analysis included 66,755 lambings from 280 breeders. The statistical model included breed, parity, litter size at previous lambing, month of the previous lambing, year of the previous lambing, breed of the ram, geographical location of the flock, interaction between month of the previous lambing and breed of the ram, interaction between parity and month of the previous lambing, interaction between breed of the ewe and month of the previous lambing, and interaction between breed of the ewe and litter size at previous lambing as fixed effects. Flock and interaction between year of the previous lambing and flock were treated randomly. Month of the previous lambing affects LI, which is gradually shortening from February to August, and prolonging from August to February. The number of live born lambs significantly affected LI. LI between the first and the second parity and between the second and the third parity was longer than between higher parities. From 1993 to 1999, the LI was decreasing, and increasing thereafter. Ewes mated with JS ram had longer lambing interval than ewes mated with IJS ram. Among all observed effects, flock affected LI the most.

  3. Slow Release of Plant Volatiles Using Sol-Gel Dispensers.

    Science.gov (United States)

    Bian, L; Sun, X L; Cai, X M; Chen, Z M

    2014-12-01

    The black citrus aphid, also known as the tea aphid, (Toxoptera aurantii Boyer) attacks economically important crops, including tea (Camellia sinensis (L.) O. Kuntze). In the current study, silica sol-gel formulations were screened to find one that could carry and release C. sinensis plant volatiles to lure black citrus aphids in a greenhouse. The common plant volatile trans-2-hexen-1-al was used as a model molecule to screen for suitable sol-gel formulations. A zNose (Electronic Sensor Technology, Newbury Park, CA) transportable gas chromatograph was used to continuously monitor the volatile emissions. A sol-gel formulation containing tetramethyl orthosilicate and methyltrimethoxysilane in an 8:2 (vol:vol) ratio was selected to develop a slow-release dispenser. The half-life of trans-2-hexen-1-al in the sol-gel dispenser increased slightly with the volume of this compound in the dispenser. Ten different volatiles were tested in the sol-gel dispenser. Alcohols of 6-10 carbons had the longest half-lives (3.01-3.77 d), while esters of 6-12 carbons had the shortest (1.53-2.28 d). Release of these volatiles from the dispensers could not be detected by the zNose after 16 d (cis-3-hexenyl acetate) to 26 d (3,7-dimethylocta-1,6-dien-3-ol). In greenhouse experiments, trans-2-hexen-1-al and cis-3-hexen-1-ol released from the sol-gel dispensers attracted aphids for ≍17 d, and release of these volatiles could not be detected by the zNose after ≍24 d. The sol-gel dispensers performed adequately for the slow release of plant volatiles to trap aphids in the greenhouse.

  4. Nanocrystalline Pentaerythritoltetranitrate using Sol-Gel Process

    Directory of Open Access Journals (Sweden)

    Sanjay Vishwasrao Ingale

    2011-10-01

    Full Text Available The secondary explosives developed with reduced particle size tend to be more insensitive for mechanical stimuli and may release energy with faster rate and gaining more importance nowadays. Therefore, aiming to reduce the particle size of one of the popular explosives, viz., pentaerythritoltetranitrate (PETN to the nanometer range, a method for preparation of nanocrystalline PETN in the silica (SiO2 gel matrix using sol-gel process has been demonstrated. The PETN-SiO2 xerogels were prepared containing PETN content ranging from 50 per cent to 90 per cent (w/w and the xerogels were characterised using different techniques. An exothermic peak at around 185 oC preceded by an endotherm in thermal analysis accompanied with weight loss in the temperature range from 150 oC to 200 oC   for the xerogel confirmed the presence of PETN in xerogel. Infrared spectra of xerogels showed peaks at around 1285 cm-1 and 1700 cm-1 assigned to O-NO2 and C-O bond representing PETN. Small angle x-ray scattering measurements on xerogels indicated that PETN entered in the pores of silica matrix. Transmission electron microscopy revealed that cystalline PETN    with particle size of around 15 nm dispersed in silica xerogel. The specific surface area for the PETN-SiO2 (90:10 xerogels was found to be 75 m2/g.Defence Science Journal, 2011, 61(6, pp.534-539, DOI:http://dx.doi.org/10.14429/dsj.61.594

  5. Analyse af VM-Husene

    DEFF Research Database (Denmark)

    Ryborg Jørgensen, Thomas

    2007-01-01

    Bearbejdet uddrag fra 'Arkitektonisk kvalitet & industrielle byggesystemer' Kunstakademiets Arkitektskole 2007 (CINARK Forskning). Papiret er anvendt i forbindelse med adskillelige arkitekturteoretiske studiekredse....

  6. Review on Sol-Gel Derived Coatings:Process, Techniques and Optical Applications

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Sol-gel process is one of the simplest techniques to manufacture thin films. The quality of the prepared films depends on the parameters of the sol-gel process and the used technique for deposition. A great variety of the sol-gel derived films have been prepared for different applications. We present a review on the sol-gel derived coatings. The description of the process is introduced in details. Different sol-gel deposition techniques are mentioned. The optical applications of the sol-gel derived coatings are reviewed.

  7. Ferrocene Derivative Mediator Bonded Sol-gel Membrane Glucose Biosensor

    Institute of Scientific and Technical Information of China (English)

    XUAN, Guang-Shan; KIM, Moon-Chang; HER, Dae-Sung; LEE, Heung-Lark

    2006-01-01

    The sol-gel derived glucose biosensor was developed, and the sol-gel membrane was organically modified by N-(3-triethoxysilylpropyl)-ferrocenylmethylamine (FcSi) as sol-gel precursor to make electrochemical biosensor.The structure of biosensor was sol-gel/FcSi+Gox/GC type (glucose oxidase, Gox). The ferrocene mediator was chemically immobilized to the silane network, and Gox was entrapped to the sol-gel glass network. Therefore,these structures prevented mediator leakage and retained the enzyme activity. Additionally, pH of electrolyte, temperature effects, and interference of positive substances with biosensor were investigated. And the electrochemical performance of biosensor was studied by amperometry. The results indicated that the linear range, detection limit,and response slope of biosensor was 2.00× 10-4-1.57× 10-3 mol·L-1, 2.0× 10-4 mol·L-1 and 5.06× 105 nA·mol-1 · L, respectively.

  8. Sol-gel applications for ceramic membrane preparation

    Science.gov (United States)

    Erdem, I.

    2017-02-01

    Ceramic membranes possessing superior properties compared to polymeric membranes are more durable under severe working conditions and therefore their service life is longer. The ceramic membranes are composed of some layers. The support is the layer composed of coarser ceramic structure and responsible for mechanical durability under filtration pressure and it is prepared by consolidation of ceramic powders. The top layer is composed of a finer ceramic micro-structure mainly responsible for the separation of components present in the fluid to be filtered and sol-gel method is a versatile tool to prepare such a tailor-made ceramic filtration structure with finer pores. Depending on the type of filtration (e.g. micro-filtration, ultra-filtration, nano-filtration) aiming separation of components with different sizes, sols with different particulate sizes should be prepared and consolidated with varying precursors and preparation conditions. The coating of sol on the support layer and heat treatment application to have a stable ceramic micro-structure are also important steps determining the final properties of the top layer. Sol-gel method with various controllable parameters (e.g. precursor type, sol formation kinetics, heat treatment conditions) is a practical tool for the preparation of top layers of ceramic composite membranes with desired physicochemical properties.

  9. Fast wave power flow along SOL field lines in NSTX

    Science.gov (United States)

    Perkins, R. J.; Bell, R. E.; Diallo, A.; Gerhardt, S.; Hosea, J. C.; Jaworski, M. A.; Leblanc, B. P.; Kramer, G. J.; Phillips, C. K.; Roquemore, L.; Taylor, G.; Wilson, J. R.; Ahn, J.-W.; Gray, T. K.; Green, D. L.; McLean, A.; Maingi, R.; Ryan, P. M.; Jaeger, E. F.; Sabbagh, S.

    2012-10-01

    On NSTX, a major loss of high-harmonic fast wave (HHFW) power can occur along open field lines passing in front of the antenna over the width of the scrape-off layer (SOL). Up to 60% of the RF power can be lost and at least partially deposited in bright spirals on the divertor floor and ceiling [1,2]. The flow of HHFW power from the antenna region to the divertor is mostly aligned along the SOL magnetic field [3], which explains the pattern of heat deposition as measured with infrared (IR) cameras. By tracing field lines from the divertor back to the midplane, the IR data can be used to estimate the profile of HHFW power coupled to SOL field lines. We hypothesize that surface waves are being excited in the SOL, and these results should benchmark advanced simulations of the RF power deposition in the SOL (e.g., [4]). Minimizing this loss is critical optimal high-power long-pulse ICRF heating on ITER while guarding against excessive divertor erosion.[4pt] [1] J.C. Hosea et al., AIP Conf Proceedings 1187 (2009) 105. [0pt] [2] G. Taylor et al., Phys. Plasmas 17 (2010) 056114. [0pt] [3] R.J. Perkins et al., to appear in Phys. Rev. Lett. [0pt] [4] D.L. Green et al., Phys. Rev. Lett. 107 (2011) 145001.

  10. Time for a Change; Spirit's View on Sol 1843 (Vertical)

    Science.gov (United States)

    2009-01-01

    NASA's Mars Exploration Rover Spirit used its navigation camera to take the images that have been combined into this full-circle view of the rover's surroundings during the 1,843rd Martian day, or sol, of Spirit's surface mission (March 10, 2009). South is in the middle. North is at both ends. This view is presented as a vertical projection with geometric seam correction. North is at the top. The rover had driven 36 centimeters downhill earlier on Sol 1854, but had not been able to get free of ruts in soft material that had become an obstacle to getting around the northeastern corner of the low plateau called 'Home Plate.' The Sol 1854 drive, following two others in the preceding four sols that also achieved little progress in the soft ground, prompted the rover team to switch to a plan of getting around Home Plate counterclockwise, instead of clockwise. The drive direction in subsequent sols was westward past the northern edge of Home Plate.

  11. Time for a Change; Spirit's View on Sol 1843 (Polar)

    Science.gov (United States)

    2009-01-01

    NASA's Mars Exploration Rover Spirit used its navigation camera to take the images that have been combined into this full-circle view of the rover's surroundings during the 1,843rd Martian day, or sol, of Spirit's surface mission (March 10, 2009). South is in the middle. North is at both ends. This view is presented as a polar projection with geometric seam correction. North is at the top. The rover had driven 36 centimeters downhill earlier on Sol 1854, but had not been able to get free of ruts in soft material that had become an obstacle to getting around the northeastern corner of the low plateau called 'Home Plate.' The Sol 1854 drive, following two others in the preceding four sols that also achieved little progress in the soft ground, prompted the rover team to switch to a plan of getting around Home Plate counterclockwise, instead of clockwise. The drive direction in subsequent sols was westward past the northern edge of Home Plate.

  12. Time for a Change; Spirit's View on Sol 1843 (Stereo)

    Science.gov (United States)

    2009-01-01

    [figure removed for brevity, see original site] Left-eye view of a color stereo pair for PIA11973 [figure removed for brevity, see original site] Right-eye view of a color stereo pair for PIA11973 NASA's Mars Exploration Rover Spirit used its navigation camera to take the images that have been combined into this stereo, full-circle view of the rover's surroundings during the 1,843rd Martian day, or sol, of Spirit's surface mission (March 10, 2009). South is in the middle. North is at both ends. This view combines images from the left-eye and right-eye sides of the navigation camera. It appears three-dimensional when viewed through red-blue glasses with the red lens on the left. The rover had driven 36 centimeters downhill earlier on Sol 1854, but had not been able to get free of ruts in soft material that had become an obstacle to getting around the northeastern corner of the low plateau called 'Home Plate.' The Sol 1854 drive, following two others in the preceding four sols that also achieved little progress in the soft ground, prompted the rover team to switch to a plan of getting around Home Plate counterclockwise, instead of clockwise. The drive direction in subsequent sols was westward past the northern edge of Home Plate. This view is presented as a cylindrical-perspective projection with geometric seam correction.

  13. Time for a Change; Spirit's View on Sol 1843 (Polar)

    Science.gov (United States)

    2009-01-01

    NASA's Mars Exploration Rover Spirit used its navigation camera to take the images that have been combined into this full-circle view of the rover's surroundings during the 1,843rd Martian day, or sol, of Spirit's surface mission (March 10, 2009). South is in the middle. North is at both ends. This view is presented as a polar projection with geometric seam correction. North is at the top. The rover had driven 36 centimeters downhill earlier on Sol 1854, but had not been able to get free of ruts in soft material that had become an obstacle to getting around the northeastern corner of the low plateau called 'Home Plate.' The Sol 1854 drive, following two others in the preceding four sols that also achieved little progress in the soft ground, prompted the rover team to switch to a plan of getting around Home Plate counterclockwise, instead of clockwise. The drive direction in subsequent sols was westward past the northern edge of Home Plate.

  14. Time for a Change; Spirit's View on Sol 1843 (Stereo)

    Science.gov (United States)

    2009-01-01

    [figure removed for brevity, see original site] Left-eye view of a color stereo pair for PIA11973 [figure removed for brevity, see original site] Right-eye view of a color stereo pair for PIA11973 NASA's Mars Exploration Rover Spirit used its navigation camera to take the images that have been combined into this stereo, full-circle view of the rover's surroundings during the 1,843rd Martian day, or sol, of Spirit's surface mission (March 10, 2009). South is in the middle. North is at both ends. This view combines images from the left-eye and right-eye sides of the navigation camera. It appears three-dimensional when viewed through red-blue glasses with the red lens on the left. The rover had driven 36 centimeters downhill earlier on Sol 1854, but had not been able to get free of ruts in soft material that had become an obstacle to getting around the northeastern corner of the low plateau called 'Home Plate.' The Sol 1854 drive, following two others in the preceding four sols that also achieved little progress in the soft ground, prompted the rover team to switch to a plan of getting around Home Plate counterclockwise, instead of clockwise. The drive direction in subsequent sols was westward past the northern edge of Home Plate. This view is presented as a cylindrical-perspective projection with geometric seam correction.

  15. Time for a Change; Spirit's View on Sol 1843 (Vertical)

    Science.gov (United States)

    2009-01-01

    NASA's Mars Exploration Rover Spirit used its navigation camera to take the images that have been combined into this full-circle view of the rover's surroundings during the 1,843rd Martian day, or sol, of Spirit's surface mission (March 10, 2009). South is in the middle. North is at both ends. This view is presented as a vertical projection with geometric seam correction. North is at the top. The rover had driven 36 centimeters downhill earlier on Sol 1854, but had not been able to get free of ruts in soft material that had become an obstacle to getting around the northeastern corner of the low plateau called 'Home Plate.' The Sol 1854 drive, following two others in the preceding four sols that also achieved little progress in the soft ground, prompted the rover team to switch to a plan of getting around Home Plate counterclockwise, instead of clockwise. The drive direction in subsequent sols was westward past the northern edge of Home Plate.

  16. Sol-gel derived contamination resistant antireflective coatings

    Science.gov (United States)

    Shen, Jun; Liu, Yuan; Wu, Guangming; Zhou, Bin; Zhang, Zhihua; Zhu, Yumei

    2011-02-01

    Silica-based sol-gel antireflective (AR) optical coatings are critical components for high peak power laser systems. It is well known that water vapor and volatile organic compounds in both the laser bay and target bay environments will reduce the antireflective efficiency and laser-damage resistance of the sol-gel AR coating. In this study, alkylation with organosilanes in the vapor state was investigated. Sol-gel AR coatings were vapor-phase treated with hexamethyldisilazane (HMDS) and trimethylchlorosilane (TMCS) at room temperature, and the resulting post-treated sol-gel AR coatings were tested for their resistance to contamination by a series of volatile organic compounds. Contact angle measurements were taken to discern the degree of silanization. After the vapor treatment of sol-gel AR coatings with organosilanes, the spectral performance of the coatings were analyzed by spectrophotometer, both before and after the exposure to volatile organic compounds. It is found that the coatings treated with ammonia and HMDS show a better contamination resistant capability. After being contaminated 70 hours with hexane, the transmittance of the coatings presents no obvious decrease. And the vapor treatment produces an increase in their damage threshold at 1064 nm (10ns pulse width) as compared to untreated control samples.

  17. Absorbability of bulk sol-gel bioactive glasses

    Energy Technology Data Exchange (ETDEWEB)

    Hamadouche, M.; Meunier, A.; Blanchat, C.; Sedel, L. [Paris-7 Univ. (France). Lab. de Recherches Orthopediques; Greenspan, D.C.; Zhong, J.P.; Torre, G.P. la [US Biomaterials Corp., Alachua, FL (United States)

    2001-07-01

    Melt-derived bioactive glasses have been used with success in various clinical applications for over 10 years. Recently, particles of sol-gel derived bioactive glasses with an initial high specific area have exhibited high osteoconductive properties, but also a significant degradability. In this work, we explored the in-vivo bioactivity and degradability of bulk sol-gel derived glasses. Two sol-gel compositions (58S and 77S Bioglass) were used. Bulk 45S5 were used as a control. Both sol-gel derived demonstrated similar osteoconductive properties to 45S% Bioglass. In addition, absorbability was observed for sol-gel derived glasses after 12 weeks of implantation. Total absorption reached 40% after 52 weeks. No degradation could be measured in the case of 45S5 melt derived Bioglass. The degradation process was highly time dependent as demonstrated by regression analysis. New bone formation was found to fill in areas that had been resorbed similar to bone remodeling. New bone was found to fill in areas that had been absorbed, similar to natural bone remodeling. This absorbability can be assumed to be at least partially related to an osteoclastic resorption, as viable osteoclasts-like cells were found directly in contact with the glass surfaces. (orig.)

  18. Structural evolution and stability of sol-gel biocatalysts

    Energy Technology Data Exchange (ETDEWEB)

    Rodgers, L.E. [School of Biotechnology and Biomolecular Sciences, University of New South Wales, NSW 2052 (Australia)]. E-mail: ler@ansto.gov.au; Knott, R.B. [Australian Nuclear Science and Technology Organisation, PMB 1, Menai, NSW 2234 (Australia); Holden, P.J. [Australian Nuclear Science and Technology Organisation, PMB 1, Menai, NSW 2234 (Australia); Pike, K.J. [Australian Nuclear Science and Technology Organisation, PMB 1, Menai, NSW 2234 (Australia); Hanna, J.V. [Australian Nuclear Science and Technology Organisation, PMB 1, Menai, NSW 2234 (Australia); Foster, L.J.R. [School of Biotechnology and Biomolecular Sciences, University of New South Wales, NSW 2052 (Australia); Bartlett, J.R. [Australian Nuclear Science and Technology Organisation, PMB 1, Menai, NSW 2234 (Australia)

    2006-11-15

    Immobilisation strategies for catalytic enzymes are important as they allow recovery and reuse of the biocatalysts. In this work, sol-gel matrices have been used to immobilise Candida antarctica lipase B (CALB), a commonly used industrial enzyme. The sol-gel bioencapsulate is produced through fluoride-catalysed hydrolysis of mixtures of tetramethylorthosilicate (TMOS) and methyltrimethoxysilane (MTMS) in the presence of CALB, yielding materials with controlled pore sizes and surface chemistries. Sol-gel matrices prolong the catalytic life and enhance the activity of CALB, although the molecular basis for this effect has yet to be elucidated due to the limitations of analytical techniques applied to date. Small angle neutron scattering (SANS) allows such multi-component systems to be characterised through contrast matching. In the sol-gel bioencapsulate system at the contrast match point for silica, residual scattering intensity is due to the CALB and density fluctuations in the matrix. A SANS contrast variation series found the match point for the silica matrix, both with and without enzyme present, to be around 35%. The model presented here proposes a mechanism for the interaction between CALB and the surrounding sol-gel matrix, and the observed improvement in enzyme activity and matrix strength. Essentially, the inclusion of CALB modulates silicate speciation during evolution of the inorganic network, leading to associated variations in SANS contrast. The SANS protocol developed here may be applied more generally to other encapsulated enzyme sys0010te.

  19. miR-27a-3p suppresses tumor metastasis and VM by down-regulating VE-cadherin expression and inhibiting EMT: an essential role for Twist-1 in HCC

    Science.gov (United States)

    Zhao, Nan; Sun, Huizhi; Sun, Baocun; Zhu, Dongwang; Zhao, Xiulan; Wang, Yong; Gu, Qiang; Dong, Xueyi; Liu, Fang; Zhang, Yanhui; Li, Xiao

    2016-01-01

    Twist-1 and miRNAs have been reported to be associated with tumor metastasis and angiogenesis. However, the relationship between Twist-1 and miRNAs and the function of miRNAs remain largely undefined. We aimed to reveal the Twist-1-related miRNA expression profile and to determine whether Twist-1 functions in tumor metastasis and vasculogenic mimicry (VM) by regulating miRNA expression in hepatocellular carcinoma (HCC). Results showed that the expression of miR-27a-3p was consistently down-regulated in HCC cell lines and tissue samples displaying high expression of Twist-1. Both loss- and gain-of-function assays revealed suppressive effects of miR-27a-3p. Low miR-27a-3p expression was significantly associated with early metastasis in HCC. Subsequent investigations revealed that miR-27a-3p mediated the inhibition of epithelial–mesenchymal transition (EMT). Additional experiments showed that VE-cadherin is a direct target of miR-27a-3p and further demonstrated the critical role of miR-27a-3p in suppressing tumor metastasis and VM. Conclusions: Twist-1 up-regulation in HepG2 cells resulted in the differential expression of 18 miRNAs. Among them, miR-27a-3p deregulation contributed to VM and metastasis. The miR-27a-3p-mediated down-regulation of VE-cadherin and inhibition of EMT may be essential for Twist-1 to induce tumor metastasis and VM. Our findings highlight the importance of miR-27a-3p and suggest a promising new strategy for anti-HCC therapy. PMID:26980408

  20. Optical detection of parasitic protozoa in sol-gel matrices

    Science.gov (United States)

    Livage, Jacques; Barreau, J. Y.; Da Costa, J. M.; Desportes, I.

    1994-10-01

    Whole cell parasitic protozoa have been entrapped within sol-gel porous silica matrices. Stationary phase promastigote cells of Leishmania donovani infantum are mixed with a silica sol before gelation occurs. They remain trapped within the growing oxide network and their cellular organization appears to be well preserved. Moreover protozoa retain their antigenic properties in the porous gel. They are still able to detect parasite specific antibodies in serum samples from infected patients via an enzyme linked immunosorbent assay (ELISA). Antigen- antibody associations occurring in the gel are optically detected via the reactions of a peroxidase conjugate with ortho-phenylenediamine leading to the formation of a yellow coloration. A clear-cut difference in optical density is measured between positive and negative sera. Such an entrapment of antigenic species into porous sol-gel matrices avoids the main problems due to non specific binding and could be advantageously used in diagnostic kits.

  1. Sol-gel derived coatings for the conservation of steel

    Directory of Open Access Journals (Sweden)

    Erika Kiele

    2015-06-01

    Full Text Available In this paper, sol-gel processing route has been applied and investigated for the conservation of steel. Nanosilica coatings on steel surface have been prepared using tetraethylorthosilicate (TEOS as a starting material. The methyl-modified silica sols were obtained by mixing of 3 mas.% SiO2 sol solution with hexamethyldisilozane (HMDS. The surface of steel was coated by dip-coating technique. In order to compare the characteristics of coatings, the steel substrates were also coated with commercial polymers Paraloid B67, Cosmolloid H80 and Antik Patina. The surface morphology changes of the uncoated and coated specimens before and after photochemical ageing were investigated by scanning electron microscopy and atomic force microscopy. The structure of the prepared coatings was also investigated by FTIR spectroscopy. The hydrophobicity of surfaces was evaluated by contact angle measurements. Potentiodynamic measurements were obtained in order to compare corrosion parameters of the coatings.

  2. Chemical Sensors Based on Molecularly Imprinted Sol-Gel Materials

    Directory of Open Access Journals (Sweden)

    Franz L. Dickert

    2010-03-01

    Full Text Available The sol-gel technique is earning the worldwide attention of researchers in the field of material science, due to its versatility in synthesizing inorganic ceramic materials at mild conditions. High purity, homogeneity, controlled porosity, stable temperature and nanoscale structuring are the most remarkable features offered by this method for generating highly sensitive and selective matrices to incorporate analyte molecules. The crafting of sol-gel sensors through molecular imprinting has put great influence on the development of innovative chemical sensors, which can be seen from the growing number of publications in this field. The review provides a brief overview of sol-gel sensor applications, and discusses the contribution of molecular imprinting in exploring the new world of sensors.

  3. The effect of sol aging time on Structural and Optical properties of sol gel ZnO doped Al

    Science.gov (United States)

    El Hallani, G.; Fazouan, N.; Liba, A.; Khuili, M.

    2016-10-01

    Currently the doped or undoped ZnO semiconductor is of great importance in the field of electronic and optoelectronic devices such as transparent conductors and optical windows of solar cells based on silicon. ZnO thin films are produced by several techniques such as sol-gel method which is a chemical technique usually dependent on solution conditions. However, the sol gel aging time is an important parameter, which can have a significant impact on the properties of thin films. In this work we studied the effect of aging times (0h, 24h, 48h, 72h, 1 week) of the precursor solution on the structural and optical properties of ZnO doped Al (3 at.%). Thin films prepared by spin coating on glass substrates were investigated. The X-ray diffraction (XRD) analysis shows that the ZnO doped Al (3 at.%) exhibit the hexagonal wurtzite structure with a preferential orientation along [002] direction. The shift of (002) peaks towards higher diffraction angles is observed with sol aging time and also, a variation of crystallite sizes and thickness of thin films are shown with increasing sol aging time. All films present an average optical transmittance around 90% in the visible range with some interference fringes indicating a relative smoothness of films. We note an increasing in transmittance level with sol aging time from 0h to 48h. We can conclude that the aging times of the precursor solution influences the structural and optical properties of studied thin films.

  4. New Record Five-Wheel Drive, Spirit's Sol 1856 (Stereo)

    Science.gov (United States)

    2009-01-01

    [figure removed for brevity, see original site] Left-eye view of a color stereo pair for PIA11962 [figure removed for brevity, see original site] Right-eye view of a color stereo pair for PIA11962 NASA's Mars Exploration Rover Spirit used its navigation camera to take the images that have been combined into this stereo, 180-degree view of the rover's surroundings during the 1,856th Martian day, or sol, of Spirit's surface mission (March 23, 2009). The center of the view is toward the west-southwest. This view combines images from the left-eye and right-eye sides of the navigation camera. It appears three-dimensional when viewed through red-blue glasses with the red lens on the left. The rover had driven 25.82 meters (84.7 feet) west-northwestward earlier on Sol 1856. This is the longest drive on Mars so far by a rover using only five wheels. Spirit lost the use of its right-front wheel in March 2006. Before Sol 1856, the farthest Spirit had covered in a single sol's five-wheel drive was 24.83 meters (81.5 feet), on Sol 1363 (Nov. 3, 2007). The Sol 1856 drive made progress on a route planned for taking Spirit around the western side of the low plateau called 'Home Plate.' A portion of the northwestern edge of Home Plate is prominent in the left quarter of this image, toward the south. This view is presented as a cylindrical-perspective projection with geometric seam correction.

  5. Optical Sensors for Biomolecules Using Nanoporous Sol-Gel Materials

    Science.gov (United States)

    Fang, Jonathan; Zhou, Jing C.; Lan, Esther H.; Dunn, Bruce; Gillman, Patricia L.; Smith, Scott M.

    2004-01-01

    An important consideration for space missions to Mars is the ability to detect biosignatures. Solid-state sensing elements for optical detection of biological entities are possible using sol-gel based biologically active materials. We have used these materials as optical sensing elements in a variety of bioassays, including immunoassays and enzyme assays. By immobilizing an appropriate biomolecule in the sol-gel sensing element, we have successfully detected analytes such as amino acids and hormones. In the case of the amino acid glutamate, the enzyme glutamate dehydrogenase was the immobilized molecule, whereas in the case of the hormone cortisol, an anti-cortisol antibody was immobilized in the sensing element. In this previous work with immobilized enzymes and antibodies, excellent sensitivity and specificity were demonstrated in a variety of formats including bulk materials, thin films and fibers. We believe that the sol-gel approach is an attractive platform for bioastronautics sensing applications because of the ability to detect a wide range of entities such as amino acids, fatty acids, hopanes, porphyrins, etc. The sol-gel approach produces an optically transparent 3D silica matrix that forms around the biomolecule of interest, thus stabilizing its structure and functionality while allowing for optical detection. This encapsulation process protects the biomolecule and leads to a more "rugged" sensor. The nanoporous structure of the sol-gel matrix allows diffusion of small target molecules but keeps larger, biomolecules immobilized in the pores. We are currently developing these biologically active sol-gel materials into small portable devices for on-orbit cortisol detection

  6. Meteor Search by Spirit, Sol 668

    Science.gov (United States)

    2005-01-01

    [figure removed for brevity, see original site] Annotated Meteor Search by Spirit, Sol 668 The panoramic cameras on NASA's Mars Exploration Rovers are about as sensitive as the human eye at night. The cameras can see the same bright stars that we can see from Earth, and the same patterns of constellations dot the night sky. Scientists on the rover team have been taking images of some of these bright stars as part of several different projects. One project is designed to try to capture 'shooting stars,' or meteors, in the martian night sky. 'Meteoroids' are small pieces of comets and asteroids that travel through space and eventually run into a planet. On Earth, we can sometimes see meteoroids become brilliant, long 'meteors' streaking across the night sky as they burn up from the friction in our atmosphere. Some of these meteors survive their fiery flight and land on the surface (or in the ocean) where, if found, they are called 'meteorites.' The same thing happens in the martian atmosphere, and Spirit even accidentally discovered a meteor while attempting to obtain images of Earth in the pre-dawn sky back in March, 2004 (see http://marsrovers.jpl.nasa.gov/gallery/press/spirit/20040311a.html, and Selsis et al. (2005) Nature, vol 435, p. 581). On Earth, some meteors come in 'storms' or 'showers' at predictable times of the year, like the famous Perseid meteor shower in August or the Leonid meteor shower in November. These 'storms' happen when Earth passes through the same parts of space where comets sometimes pass. The meteors we see at these times are from leftover debris that was shed off of these comets. The same kind of thing is predicted for Mars, as well. Inspired by calculations about Martian meteor storms by meteor scientists from the University of Western Ontario in Canada and the Centre de Recherche en Astrophysique de Lyon in France, and also aided by other meteor research colleagues from NASA's Marshall Space Flight Center, scientists on the rover team

  7. Sol-gel derived oxides and mixed oxides catalysts with narrow mesoporous distribution

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    A novel sol-gel process for preparing oxides and mixed oxides sols from precipitation and peptization process is reported in this article. Inorganic salts are used as raw materials in this study. It is found that the amount of acid has great influence on the stability and particle diameter distribution of the precursor sols. Ultrasonic treatment is used to prepare alumina sol at room temperature. The result of 27Al NMR shows that there exist Al137+ species in the sol. By controlling the sol particles with narrow particle diameter distribution, alumina, titania and silica-alumina (SA) materials with narrow mesoporous distribution are formed by regular packing of sol particles during gelation without using any templates. The results also show that the structure and particle diameter distribution of precursor sol determine the final materials' texture.

  8. The SOL-2/Neto auxiliary protein modulates the function of AMPA-subtype ionotropic glutamate receptors.

    Science.gov (United States)

    Wang, Rui; Mellem, Jerry E; Jensen, Michael; Brockie, Penelope J; Walker, Craig S; Hoerndli, Frédéric J; Hauth, Linda; Madsen, David M; Maricq, Andres V

    2012-09-06

    The neurotransmitter glutamate mediates excitatory synaptic transmission by gating ionotropic glutamate receptors (iGluRs). AMPA receptors (AMPARs), a subtype of iGluR, are strongly implicated in synaptic plasticity, learning, and memory. We previously discovered two classes of AMPAR auxiliary proteins in C. elegans that modify receptor kinetics and thus change synaptic transmission. Here, we have identified another auxiliary protein, SOL-2, a CUB-domain protein that associates with both the related auxiliary subunit SOL-1 and with the GLR-1 AMPAR. In sol-2 mutants, behaviors dependent on glutamatergic transmission are disrupted, GLR-1-mediated currents are diminished, and GLR-1 desensitization and pharmacology are modified. Remarkably, a secreted variant of SOL-1 delivered in trans can rescue sol-1 mutants, and this rescue depends on in cis expression of SOL-2. Finally, we demonstrate that SOL-1 and SOL-2 have an ongoing role in the adult nervous system to control AMPAR-mediated currents.

  9. Identification, expression, and immuno-reactivity of Sol i 2 & Sol i 4 venom proteins of queen red imported fire ants, Solenopsis invicta Buren (Hymenoptera: Formicidae).

    Science.gov (United States)

    Lockwood, Stephanie A; Haghipour-Peasley, Jilla; Hoffman, Donald R; Deslippe, Richard J

    2012-10-01

    We report on two low-molecular weight proteins that are stored in the venom of queen red imported fire ants (Solenopsis invicta). Translated amino acid sequences identified one protein to have 74.8% identity with the Sol i 2w worker allergen, and the other protein was found to have 96/97% identity with Sol i 4.01w/4.02w worker allergens. Both Sol i 2 and Sol i 4 queen and worker proteins were expressed using pEXP1-DEST vector in SHuffle™ T7 Express lysY Escherichia coli. Proteins were expressed at significant concentrations, as opposed to the μg/ml amounts by our previous expression methods, enabling further study of these proteins. Sol i 2q protein bound weakly to human IgE, sera pooled from allergic patients, whereas Sol i 2w, Sol i 4.01w, and Sol i 4q proteins bound strongly. Despite Sol i 2w and Sol i 2q proteins having 74.8% identity, the queen protein is less immuno-reactive than the worker allergen. This finding is consistent with allergic individuals being less sensitive to queen than worker venom. Copyright © 2012 Elsevier Ltd. All rights reserved.

  10. Synthesis of phthalocyanine doped sol-gel materials

    Science.gov (United States)

    Dunn, Bruce

    1993-01-01

    The synthesis of sol-gel silica materials doped with three different types of metallophthalocyanines has been studied. Homogeneous materials of good optical quality were prepared and the first optical limiting measurements of dyes in sol-gel hosts were carried out. The properties of these solid state limiters are similar to limiters based on phthalocyanine (Pc) in solution. Sol-gel silica materials containing copper, tin and germanium phthalocyanines were investigated. The initial step in all cases was to prepare silica sols by the sonogel method using tetramethoxy silane (TMOS), HCl and distilled water. Thereafter, the synthesis depended upon the specific Pc and its solubility characteristics. Copper phthalocyanine tetrasulfonic acid tetra sodium salt (CuPc4S) is soluble in water and various doping levels (1 x 10 (exp -4) M to 1 x 10 (exp -5) M) were added to the sol. The group IV Pc's, SnPc(OSi(n-hexyl)3)2 and GePc(OSi(n-hexyl)3)2, are insoluble in water and the process was changed accordingly. In these cases, the compounds were dissolved in THF and then added to the sol. The Pc concentration in the sol was 2 x 10(exp -5)M. The samples were then aged and dried in the standard method of making xerogel monoliths. Comparative nanosecond optical limiting experiments were performed on silica xerogels that were doped with the different metallophthalocyanines. The ratio of the net excited state absorption cross section (sigma(sub e)) to the ground state cross section (sigma(sub g)) is an important figure of merit that is used to characterize these materials. By this standard the SnPc sample exhibits the best limiting for the Pc doped sol-gel materials. Its cross section ratio of 19 compares favorably with the value of 22 that was measured in toluene. The GePc materials appear to not be as useful as those containing SnPc. The GePc doped solids exhibit a higher onset energy (2.5 mj and lower cross section ratio, 7. The CuPc4S sol-gel material has a still lower cross

  11. Sol-gel based oxidation catalyst and coating system using same

    Science.gov (United States)

    Watkins, Anthony N. (Inventor); Leighty, Bradley D. (Inventor); Oglesby, Donald M. (Inventor); Patry, JoAnne L. (Inventor); Schryer, Jacqueline L. (Inventor)

    2010-01-01

    An oxidation catalyst system is formed by particles of an oxidation catalyst dispersed in a porous sol-gel binder. The oxidation catalyst system can be applied by brush or spray painting while the sol-gel binder is in its sol state.

  12. Update History of This Database - eSOL | LSDB Archive [Life Science Database Archive metadata

    Lifescience Database Archive (English)

    Full Text Available switchLanguage; BLAST Search Image Search Home About Archive Update History Data ...List Contact us eSOL Update History of This Database Date Update contents 2016/05/30 eSOL English archive si...ription Download License Update History of This Database Site Policy | Contact Us Update History of This Database - eSOL | LSDB Archive ...

  13. Preparation and antioxidant capacity of element selenium nanoparticles sol-gel compounds.

    Science.gov (United States)

    Bai, Yan; Qin, Biyin; Zhou, Yanhui; Wang, Yudong; Wang, Zi; Zheng, Wenjie

    2011-06-01

    This paper reported the preparation and antioxidant capacities of element selenium nanoparticles (nanoSe(0))-ascorbic acid (Vc) sol and nanSe(0)/Vc/selenocystine (SeCys) sol-gel compounds. NanoSe(0)-Vc sol was prepared by reduction of selenious dioxide (SeO2) with Vc. In the nanoSe(0)-Vc sol, highly concentrated Vc was also used as a modifier to modulate the diameter of Se(0) nanoparticles in the liquid phase. Then excellent nanoSe(0) sol-gel compounds were obtained by adding SeCys into the nanoSe(0)-Vc sol. The structure of the nanoSe(0)/Vc/SeCys sol-gel compounds was defined, which was constructed via C-Se, Se-H and O=C-Se valences and by interaction between SeCys and Vc via peptide bonds, esterification and dehydration. The antioxidant capacities of the nanoSe(0)-Vc sol and the nanoSe(0)Vc/SeCys sol-gel compounds were estimated by oxygen radical absorption capacity (ORAC) assay. The nanoSe(0)/Vc/SeCys sol-gel compounds possessed a strong antioxidant capacity due to forming the perfect three-dimensional (3D) frameworks structure. The results suggested that the nanoSe(0)-Vc sol and the nanoSe(0)Vc/SeCys sol-gel compounds might be potential medicine, especially antioxidant.

  14. Structure of hybrid organic-inorganic sols for the preparation of hydrothermally stable membranes

    NARCIS (Netherlands)

    Castricum, H.L.; Sah, A.; Geenevasen, J.A.J.; Kreiter, R.; Blank, D.H.A.; Vente, J.F.; ten Elshof, J.E.

    2008-01-01

    A procedure for the preparation of hybrid sols for the synthesis of organic-inorganic microporous materials and thin film membranes is reported. We describe silane reactivity and sol structure for acid-catalysed colloidal sols from mixtures of either tetraethylorthosilicate (TEOS) and methyltriethox

  15. The effect of plasma fluctuations on parallel transport parameters in the SOL

    DEFF Research Database (Denmark)

    Havlíčková, E.; Fundamenski, W.; Naulin, Volker

    2011-01-01

    in the scrape-off layer (SOL) taking into account these fluctuations is presented. Plasma transport in the SOL along the magnetic field between two targets is calculated by a one-dimensional fluid code in order to estimate the response to transient conditions along the SOL and the attention is given...

  16. Protein interactions with nanoporous sol-gel derived bioactive glasses.

    Science.gov (United States)

    Lin, Sen; Van den Bergh, Wouter; Baker, Simon; Jones, Julian R

    2011-10-01

    Sol-gel derived bioactive glasses are excellent candidates for bone regenerative implant materials as they bond with bone, stimulate bone growth and degrade in the body. Their interactions with proteins are critical to understanding their performance after implantation. This study focuses on the interactions between fibrinogen and sol-gel glass particles of the 70S30C (70 mol.% SiO(2), 30 mol.% CaO composition). Sol-gel silica and melt-derived Bioglass® were also used for comparison. Fibrinogen penetration into the nanoporous glasses was observed by live tracking the fluorescent-labelled fibrinogen with confocal microscopy. The effect of pore size on protein penetration was investigated. Nanoporous networks with modal pore diameters larger than 6 nm were accessible to fibrinogen. When the modal nanopore diameter was decreased to 2 nm or less, the penetration of fibrinogen was inhibited. The surface properties of the glasses, which can be modulated by media pH, glass composition and final stabilisation temperature in the sol-gel process, have effects on fibrinogen adsorption via long-range Coulombic forces before the adsorption and via short-range interactions such as hydrogen bonding after the adsorption.

  17. Sol-gel matrices for direct colorimetric detection of analytes

    Science.gov (United States)

    Charych, Deborah H.; Sasaki, Darryl; Yamanaka, Stacey

    2000-01-01

    The present invention relates to methods and compositions for the direct detection of analytes using color changes that occur in immobilized biopolymeric material in response to selective binding of analytes to their surface. In particular, the present invention provides methods and compositions related to the encapsulation of biopolymeric material into metal oxide glass using the sol-gel method.

  18. Stoichiometric hydroxyapatite obtained by precipitation and sol gel processes

    OpenAIRE

    C. Guzmán Vázquez; C. Piña Barba; N. Munguía

    2005-01-01

    Three methods for obtaining hydroxiapatite (HA) are described. HA is a very interesting ceramic because of its many medical applications. The first two precipitation methods start from calcium and phosphorous compounds, whereas the third method is a sol-gel process that uses alcoxides. The products were characterized and compared. The observed differences are important for practical applications.

  19. ARSENIC REMOVAL USING SOL-GEL SYNTHESIZED TITANIUM DIOXIDE NANOPARTICLES

    Science.gov (United States)

    In this study, the effectiveness of TiO2 nanoparticles in arsenic adsorption was examined. TiO2 particles (LS) were synthesized via sol-gel techniques and characterized for their crystallinity, surface area and pore volume. Batch adsorption studies were perf...

  20. Process of forming a sol-gel/metal hydride composite

    Science.gov (United States)

    Congdon, James W.

    2009-03-17

    An external gelation process is described which produces granules of metal hydride particles contained within a sol-gel matrix. The resulting granules are dimensionally stable and are useful for applications such as hydrogen separation and hydrogen purification. An additional coating technique for strengthening the granules is also provided.

  1. Kombinerede sol/varmepumpeanlæg i praksis

    DEFF Research Database (Denmark)

    Andersen, Elsa; Furbo, Simon

    2010-01-01

    I rapporten analyseres målinger fra kombinerede sol/varmepumpeanlæg i praksis. Anlæggene er installeret af Nordic Energy Group og målingerne er ligeledes foretaget af Nordic Energy Group. Analysen viser at energiforbruget og energiprisen kan reduceres betragteligt ved at installere et kombianlæg i...

  2. Photolithography fabrication of sol-gel ridge waveguides

    Science.gov (United States)

    Sara, Rahmani; Touam, Tahar; Blanchetiere, Chantal; Saddiki, Z.; Saravanamuttu, Kalaichelvi; Du, Xin M.; Chrostowski, Jacek; Andrews, Mark P.; Najafi, S. Iraj

    1998-07-01

    We report on fabrication of ridge waveguides in UV-light sensitive glass sol-gel thin films, deposited on silicon substrate, using a simple photolithography process. The single-layer films are prepared at low temperature and deep UV-light (DUV) is employed to make the waveguides. The effect of fabrication parameters on waveguide shape is investigated.

  3. Linking the Virginia SOL Assessments to NWEA MAP Tests

    Science.gov (United States)

    Northwest Evaluation Association, 2016

    2016-01-01

    Northwest Evaluation Association™ (NWEA™) is committed to providing partners with useful tools to help make inferences from the Measures of Academic Progress® (MAP®) interim assessment scores. Recently, NWEA completed a concordance study to connect the scales of the Virginia Standards of Learning (SOL) reading and math tests with those of the MAP…

  4. PROPRIETES DU SOL ET DOMESTICATION DE Lippia multiflora ...

    African Journals Online (AJOL)

    AISA

    C'est une plante héliophile qui s'accommode bien sur sols pauvres, moyennement acides .... (Hp) et la masse foliaire (Mfe). Analyse des donnees .... profondeur ( cm) no m b re de ra c in e s. Lomo-sud. Yaakro. Anikro. Abidjan. Yamoussoukro.

  5. Iron Oxide Silica Derived from Sol-Gel Synthesis

    Directory of Open Access Journals (Sweden)

    João Carlos Diniz da Costa

    2011-02-01

    Full Text Available In this work we investigate the effect of iron oxide embedded in silica matrices as a function of Fe/Si molar ratio and sol pH. To achieve homogeneous dispersion of iron oxide particles, iron nitrate nonahydrate was dissolved in hydrogen peroxide and was mixed with tetraethyl orthosilicate and ethanol in a sol-gel synthesis method. Increasing the calcination temperature led to a reduction in surface area, although the average pore radius remained almost constant at about 10 Å, independent of the Fe/Si molar ratio or sol pH. Hence, the densification of the matrix was accompanied by similar reduction in pore volume. However, calcination at 700 °C resulted in samples with similar surface area though the iron oxide content increased from 5% to 50% Fe/Si molar ratio. As metal oxide particles have lower surface area than polymeric silica structures, these results strongly suggest that the iron oxides opposed the silica structure collapse. The effect of sol pH was found to be less significant than the Fe/Si molar ratio in the formation of molecular sieve structures derived from iron oxide silica.

  6. Sol-gel based alumina powders with catalytic applications

    Science.gov (United States)

    Crişan, Maria; Zaharescu, Maria; Kumari, Valluri Durga; Subrahmanyam, Machiraju; Crişan, Dorel; Drăgan, Nicolae; Răileanu, Mălina; Jitianu, Mihaela; Rusu, Adriana; Sadanandam, Gullapelli; Krishna Reddy, Jakkidi

    2011-10-01

    The sol-gel process provides a new approach to the preparation of oxide materials and offers many advantages for making catalysts. Since homogeneous mixing can be achieved at the molecular scale, the chemical reactivity of the oxide surface can be greatly enhanced; thus powders with high surface area and optimized pore size distribution can be obtained at low temperatures. In the present work NiO/Al 2O 3 sol-gel catalysts were obtained by simultaneous gelation of aluminium isopropoxide and nickel nitrate. A comparative study with pure sol-gel alumina was also realized. By physical-structural studies the changes induced by the introduction of the Ni precursor, before and after aluminium alkoxide hydrolysis were highlighted. The introduction of Ni at the beginning of the reaction favors γ-Al 2O 3 crystallization. When Ni is added at the end of reaction, it delays the alumina crystallization and induces the disorder of the lattice. The obtained Ni doped sol-gel derived alumina has been used as catalyst in the finished form for glycerol reforming to generate H 2 for fuel cell applications. Some evaluation results of Ni-doped alumina combined with TiO 2 in photocatalytic glycerol reforming reaction have been included.

  7. "What D'ya Mean, Project SOL-FA?"

    Science.gov (United States)

    Hardman, Olga S.

    1981-01-01

    Since 1977, Project Sol-fa, funded with an ESEA Title IV-C grant has provided Harrison County primary teachers with inservice training in the Kodaly method of music education. This article provides information on program funding, costs, and accomplishments. Evaluation forms and the inservice syllabus are appended. (SJL)

  8. Neutron detector based on lithiated sol-gel glass

    CERN Document Server

    Wallace, S; Miller, L F; Dai, S

    2002-01-01

    A neutron detector technology is demonstrated based on sup 6 Li/ sup 1 sup 0 B doped sol-gel glass. The detector is a sol-gel glass film coated silicon surface barrier detector (SBD). The ionized charged particles from (n, alpha) reactions in the sol-gel film enter the SBD and are counted. Data showing that gamma-ray pulse amplitudes interfere with identifying charged particles that exit the film layer with energies below the gamma-ray energy is presented. Experiments were performed showing the effect of sup 1 sup 3 sup 7 Cs and sup 6 sup 0 Co gamma rays on the SBD detector. The reaction product energies of the triton and alpha particles from sup 6 Li are significantly greater than the energies of the Compton electrons from high-energy gamma rays, allowing the measurement of neutrons in a high gamma background. The sol-gel radiation detection technology may be applicable to the characterization of transuranic waste, spent nuclear fuel and to the monitoring of stored plutonium.

  9. Recent progress towards a quantitative description of filamentary SOL transport

    DEFF Research Database (Denmark)

    Carralero, D.; Siccinio, M.; Komm, M.

    2017-01-01

    A summary of recent results on filamentary transport, mostly obtained with the ASDEX-Upgrade tokamak (AUG), is presented and discussed in an attempt to produce a coherent picture of scrape-off layer (SOL) filamentary transport. A clear correlation is found between L-mode density shoulder formatio...

  10. Safe and Environmentally Acceptable Sol-gel Derived Pyrophoric Pyrotechnics

    Energy Technology Data Exchange (ETDEWEB)

    Simspon, R L; Satcher, J H; Gash, A

    2004-06-10

    It was demonstrated that highly porous sol-gel derived iron (III) oxide materials could be reduced to sub-micron-sized metallic iron by heating the materials to intermediate temperatures in a hydrogen atmosphere. Through a large number of experiments complete reduction of the sol-gel based materials was realized with a variety of hydrogen-based atmospheres (25-100% H{sub 2} in Ar, N{sub 2}, CO{sub 2}, or CO) at intermediate temperatures (350 C to 700 C). All of the resulting sol-gel-derived metallic iron powders were ignitable by thermal methods, however none were pyrophoric. For comparison several types of commercial micron sized iron oxides Fe2O3, and NANOCAT were also reduced under identical conditions. All resulting materials were characterized by thermal gravimetric analysis (TGA), differential thermal analysis (DTA), powder X-ray diffraction (PXRD), as well as scanning and transmission electron microscopies (SEM and TEM). In addition, the reduction of the iron oxide materials was monitored by TGA. In general the sol-gel materials were more rapidly reduced to metallic iron and the resulting iron powders had smaller particle sizes and were more easily oxidized than the metallic powders derived from the micron sized materials. The lack of pyrophoricity of the smaller fine metallic powders was unexpected and may in part be due to impurities in the materials that create a passivation layer on the iron. Several recommendations for future study directions on this project are detailed.

  11. Synthesis of organic-inorganic hybrid sols with nano silica particles and organoalkoxysilanes for transparent and high-thermal-resistance coating films using sol-gel reaction.

    Science.gov (United States)

    Na, Moonkyong; Park, Hoyyul; Ahn, Myeongsang; Lee, Hyeonhwa; Chung, Ildoo

    2010-10-01

    Organic-inorganic hybrid sols were synthesized from nano silica particles dispersed in water and from organoalkoxysilanes, using the sol-gel reaction. This work focuses on the effects of the three multifunctional organoalkoxysilanes dimethyldimethoxysilane (DMDMS), methyltrimethoxysilane (MTMS), and tetramethoxysilane (TMOS) to form a transparent and high-thermal-resistance coating film. The stability of the hybrid sol was evaluated as a function of the reaction time for 10 d through the variation of the viscosity. The viscosity of the silica/DMDMS and silica/MTMS sol was slightly increased for 10 d. The multifunctional organoalkoxysilanes formed dense silica networks through hydrolysis and condensation reaction, which enhanced the thermal resistance of the coating films. No thermal degradation of the silica/DMDMS sample occurred up to 600 degrees C, and none of the silica/MTMS and silica/TMOS samples occurred either up to 700 degrees C. The organic-inorganic hybrid sols were coated on the glass substrate using a spin-coating procedure. The organic-inorganic hybrid sols formed flat coating films without cracks. The transmittance of the hybrid sol coating films using MTMS and DMDMS was shown to be over 90%. The transmittance of the silica/TMOS sol coating film reacted for 10 d abruptly decreased due to faster gelation. The silica/DMDMS and silica/MTMS hybrid sols formed smooth coating films while the surface roughness of the silica/TMOS coating film markedly increased when the hybrid sol reacted for 10 d. The increase of the surface roughness of the silica/TMOS coating film can be attributed to the degradation of the stability of the hybrid sol and to the loss of transmittance of the coating film. It was confirmed in this study that the use of organic-inorganic hybrid sol can yield transparent and high-thermal-resistance coating films.

  12. Low-Temperature Preparation and Properties of High Activity Anatase TiO2 Aqueous Sols

    Science.gov (United States)

    Liu, Qingju; Na, Wei; Zhu, Zhongqi; Zhang, Jin

    2011-06-01

    Anatase TiO2 aqueous sols were prepared below 70 °C by sol method. The influences of preparing conditions on the crystal structures and stability of the sols were investigated with X-ray diffraction (XRD) and Zeta potential. The photocatalytic activities of the anatase TiO2 aqueous sols were characterized by degradation of methyl orange and methylene blue under ultraviolet light, fluorescent light and sunlight. The sols demonstrate higher photocatalytic activity than that of Degussa P25-TiO2.

  13. Investigation of SOL parameters and divertor particle flux from electric probe measurements in KSTAR

    Energy Technology Data Exchange (ETDEWEB)

    Bak, J.G., E-mail: jgbak@nfri.re.kr [National Fusion Research Institute, Daejeon (Korea, Republic of); Kim, H.S. [National Fusion Research Institute, Daejeon (Korea, Republic of); Bae, M.K. [Hanyang University, Seoul (Korea, Republic of); Juhn, J.W.; Seo, D.C.; Bang, E.N. [National Fusion Research Institute, Daejeon (Korea, Republic of); Shim, S.B. [Pusan National University, Pusan (Korea, Republic of); Chung, K.S. [Hanyang University, Seoul (Korea, Republic of); Lee, H.J. [Pusan National University, Pusan (Korea, Republic of); Hong, S.H. [National Fusion Research Institute, Daejeon (Korea, Republic of)

    2015-08-15

    The upstream scrape-off layer (SOL) profiles and downstream particle fluxes are measured with a fast reciprocating Langmuir probe assembly (FRLPA) at the outboard mid-plane and a fixed edge Langmuir probe array (ELPA) at divertor region, respectively in the KSTAR. It is found that the SOL has a two-layer structure in the outboard wall-limited (OWL) ohmic and L-mode: a near SOL (∼5 mm zone) with a narrow feature and a far SOL with a broader profile. The near SOL width evaluated from the SOL profiles in the OWL plasmas is comparable to the scaling for the L-mode divertor plasmas in the JET and AUG. In the SOL profiles and the divertor particle flux profile during the ELMy H-modes, the characteristic e-folding lengths of electron temperature, plasma density and particle flux during an ELM phase are about two times larger than ones at the inter ELM.

  14. [Studies on nano-particle sols of hydroxyaptite and titanium dioxide for haemo-compatibility].

    Science.gov (United States)

    Chen, Xiao; Feng, Lingyun; Peng, Renxiu; Cao, Xianying

    2002-06-01

    A biological evaluation is conducted for two types of nano-particle sols, hydroxyaptite(HAP) and titanium dioxide(TiO2). The results show that HAP sol significnatly prolongs the bleeding time and coagulation time of mice as well as the prothrombin time(PT) and partial thromboplastin time(PTT) of rats while TiO2 sol exhibits no such effects. Neither HAP sol nor TiO2 sol instigated in-vitro hemolysis of rabbit erythrocyte. However, both of the materials caused in-vitro aggregation of rabbit erythrocytes. The reason underlying the different results as to the two types of material is their specific stabilizer, heparin for HAP sol and PVC for TiO2 sol. We came to the conclusion that a biologically inert stablizer has no less significance than the nano-particle's very own nature in a nano-material's application prospect.

  15. INKJET PRINTING OF ALUMOOXIDE SOL FOR DEPOSITION OF ANTIREFLECTING COATINGS

    Directory of Open Access Journals (Sweden)

    E. A. Eremeeva

    2017-01-01

    Full Text Available Subject of Research. This work describes for the first time the formation of antireflective coating on the base of boehmite phase of AlOOH with low refractive index (1.35 by inkjet printing on the nonporous substrate. This method gives the possibility to increase the contrast of colorful interfering images by 32% obtaining by inkjet printing of titanium dioxide sol. The usage of this technology enables to obtain patterns with wide viewing angle and makes them highly stable. Methods. Traditional sol-gel method with peptizing agents and heating for 90oC was applied for sol synthesis. Then the mixture was under sonic treatment for the obtaining of viscous sol. The viscosity was determined by Brookfield HA/HB viscometer, and the surface tension by Kyowa DY-700 tensiometer. Aluminum oxide ink was deposited on polished slides (26×76 mm2, Paul Marienfeld, Germany, over titanium oxide layer. To print titania ink, we use a desktop office printer Canon Pixma IP 2840 and Dimatix DMP-2831. The thickness of an inkjet AlOOH layer after drying in the air and removal of the solvents did not exceed 150 nm with an RI not less than 1.35 in the entire visible range. Results. The stable colloidal ink was obtained for the first time on the base of aluminum oxide matrix with neutral pH. The rheology was regulated by controlling parameters of sol-gel method in the system of aqueous titanium dioxide sol and by adding ethanol that affects the charge of double electrical layer of disperse phase. The controllable coalesce of drops enables to apply antireflection coating within the thickness accuracy of 10 nm. The morphology of particles and the topology of printed structures were analyzed by optical, scanning electron and atomic-force microscopes. Practical Relevance. We have proposed the approach to obtain colorful, interference patterns using two types of high refractive inks with different refractive indexes. The inkjet printing method opens new opportunities for

  16. Germinación, microinjertación y cultivo de callos in vitro de Vasconcellea stipulata V.M. Badillo y Vasconcellea pubescens A.DC

    OpenAIRE

    2016-01-01

    En varias poblaciones rurales de regiones andinas y centroamericanas se utilizan con fines etnomédicos las hojas, el látex y el fruto de las plantas de la familia Caricaceae cuyo miembro más representativo es la papaya (Carica papaya L.), la cual produce la fuente comercial más importante de la enzima proteolítica papaína. El presente trabajo estudia las especies Vasconcellea stipulata V.M. Badillo y Vasconcellea pubescens A.DC que pertenecen al género Vasconcellea, miembros de la familia Car...

  17. Luminescent hybrid porphyrinosilica obtained by sol gel chemistry

    Directory of Open Access Journals (Sweden)

    Neri Cláudio Roberto

    2003-01-01

    Full Text Available The sol-gel process is a methodology used to obtain organic-inorganic hybrid solids, which open new possibilities in the field of material science. The sol-gel technique offers a low temperature attractive approach for introducing organic molecules into amorphous materials. In order to introduce tetrakis (2-hydroxy-5-nitrophenylporphyrin covalently bounded to a silicate matrix, the inorganic precursor 3-isocyanatopropyltriethoxysilane was added (molar ratio 2:1 to the porphyrin solution in anhydrous dimethylformamide and triethylamine. The isolated porphyrin and the hybrid porphyrinosilica have excitation maximum centred at 400 nm and 424 nm, respectively and the emission spectra for both materials has bands centred at 650 nm and 713 nm. The formation of hybrid matrix was investigated by FTIR.

  18. Tough ceramic coatings: Carbon nanotube reinforced silica sol-gel

    Energy Technology Data Exchange (ETDEWEB)

    Lopez, A.J., E-mail: antoniojulio.lopez@urjc.es [Dept. de Ciencia e Ingenieria de Materiales, ESCET, Universidad Rey Juan Carlos, C/Tulipan s/n, Mostoles 28933, Madrid (Spain); Rico, A.; Rodriguez, J.; Rams, J. [Dept. de Ciencia e Ingenieria de Materiales, ESCET, Universidad Rey Juan Carlos, C/Tulipan s/n, Mostoles 28933, Madrid (Spain)

    2010-08-15

    Silica coatings reinforced with carbon nanotubes were produced via sol-gel route using two mixing techniques of the sol-gel precursors, mechanical and ultrasonic mixing, and dip-coating as deposition process on magnesium alloy substrates. Effective incorporation and distribution of 0.1 wt.% of carbon nanotubes in the amorphous silica matrix of the coatings were achieved using both techniques. Fabrication procedure determines the morphological aspects of the coating. Only mechanical mixing process produced coatings dense and free of defects. Nanoindentation technique was used to examine the influence of the fabrication process in the mechanical features of the final coatings, i.e. indentation fracture toughness, Young's modulus and hardness. A maximum toughening effect of about 24% was achieved in silica coatings reinforced with carbon nanotubes produced by the mechanical mixing route. Scanning electron microscopy investigation revealed that the toughening of these reinforced coatings was mainly due to bridging effect of the reinforcement.

  19. Dust Devil in Spirit's View Ahead on Sol 1854

    Science.gov (United States)

    2009-01-01

    NASA's Mars Exploration Rover Spirit used its navigation camera to take the images that have been combined into this stereo, 180-degree view of the rover's surroundings during the 1,854th Martian day, or sol, of Spirit's surface mission (March 21, 2009). The rover had driven 13.79 meters (45 feet) westward earlier on Sol 1854. West is at the center, where a dust devil is visible in the distance. North on the right, where Husband Hill dominates the horizon; Spirit was on top of Husband Hill in September and October 2005. South is on the left, where lighter-toned rock lines the edge of the low plateau called 'Home Plate.' This view is presented as a cylindrical projection with geometric seam correction.

  20. Sol-Gel Synthesized Adsorbents for Metal Separation

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    A series of organo-ceramic adsorbents have been synthesized by a sol-gel processing technique for metal ion extraction. These adsorbents generally have significantly high metal uptake capacities, good physical-chemical stabilities, and well-designed pore geometries compared to other pre-existing metalchelating ceramic-based adsorbents. This work describes the synthesis and evaluation of pyrazole and calix[4]arene crown adsorbents for selective separation of platinum, palladium, and gold and cesium ions,respectively, from solutions. These materials exhibit mesoporous properties with high surface areas and pore volumes. The sol-gel synthesis starting with precursor silanes and titania results in gel particles of desired pore characteristics and high capacity and stability. Characterization studies, such as adsorption isotherms, breakthrough curves for fixed bed operation, and material stability, show promising results for applications to metal sepation.

  1. Tunable Optical Properties of Metal Nanoparticle Sol-Gel Composites

    Science.gov (United States)

    Smith, David D.; Snow, Lanee A.; Sibille, Laurent; Ignont, Erica

    2001-01-01

    We demonstrate that the linear and non-linear optical properties of sol-gels containing metal nanoparticles are highly tunable with porosity. Moreover, we extend the technique of immersion spectroscopy to inhomogeneous hosts, such as aerogels, and determine rigorous bounds for the average fractional composition of each component, i.e., the porosity of the aerogel, or equivalently, for these materials, the catalytic dispersion. Sol-gels containing noble metal nanoparticles were fabricated and a significant blue-shift in the surface plasmon resonance (SPR) was observed upon formation of an aerogel, as a result of the decrease in the dielectric constant of the matrix upon supercritical extraction of the solvent. However, as a result of chemical interface damping and aggregation this blue-shift does not strictly obey standard effective medium theories. Mitigation of these complications is achieved by avoiding the use of alcohol and by annealing the samples in a reducing atmosphere.

  2. Nanostructured energetic materials using sol-gel methodologies

    Energy Technology Data Exchange (ETDEWEB)

    Tillotson, T M; Simpson, R L; Hrubesh, L W; Gash, A E; Thomas, I M; Poco, J F

    2000-09-27

    The fundamental differences between energetic composites and energetic materials made from a monomolecular approach are the energy density attainable and the energy release rates. For the past 4 years, we have been exploiting sol-gel chemistry as a route to process energetic materials on a microstructural scale. At the last ISA conference, we described four specific sol-gel approaches to fabricating energetic materials and presented our early work and results on two methods - solution crystallization and powder addition. Here, we detail our work on a third approach, energetic nanocomposites. Synthesis of thermitic types of energetic nanocomposites are presented using transition and main group metal-oxide skeletons. Results on characterization of structure and performance will also be given.

  3. Nanostructured Energetci Matreials with sol-gel Chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Gash, A; Satcher, J; Simpson, R; Clapsaddle, B

    2003-11-18

    The utilization of nanomaterials in the synthesis and processing of energetic materials (i.e., pyrotechnics, explosives, and propellants) is a relatively new area of science and technology. Previous energetic nanomaterials have displayed new and potentially beneficial properties, relative to their conventional analogs. Unfortunately some of the energetic nanomaterials are difficult and or expensive to produce. At LLNL we are studying the application of sol-gel chemical methodology to the synthesis of energetic nanomaterials components and their formulation into energetic nanocomposites. Here sol-gel synthesis and formulation techniques are used to prepare Fe{sub 2}O{sub 3}/Al pyrotechnic nanocomposites. The preliminary characterization of their thermal properties and the degree of mixing between fuel and oxidizer phases is contrasted with that of a conventional pyrotechnic mixture.

  4. Sol-gel multicapillary columns for gas-solid chromatography.

    Science.gov (United States)

    Sidelnikov, Vladimir N; Patrushev, Yuri V; Belov, Yuri P

    2006-01-06

    In this work, we report the method for the preparation of multicapillary columns (MCCs) for gas-solid chromatography. The porous layer adsorbent is formed on capillary walls by the hydrolysis of aluminum alkoxide in the presence of polypropylene glycol (PPG) and HCl. Porosity and selectivity of the adsorbent depend on reaction conditions and the concentration of PPG. Sol-gel MCCs are well suited for high-speed chromatographic analysis of light hydrocarbons by gas-solid chromatography. Nine-component mixtures of C1-C4 hydrocarbons are separated within 8-12 s. The efficiency of 25-30 cm long alumina sol-gel MCCs consisting of approximately 1400 capillaries of 40 microm diameter is up to 2500-3000 theoretical plates.

  5. Opportunity's View on Sols 1803 and 1804 (Polar)

    Science.gov (United States)

    2009-01-01

    NASA's Mars Exploration Rover Opportunity used its navigation camera to take the images combined into this full-circle view of the rover's surroundings during the 1,803rd and 1,804th Martian days, or sols, of Opportunity's surface mission (Feb. 18 and 19, 2009). South is at the center; north at both ends. The rover had driven 55 meters on Sol 1803 before beginning to take the frames in this view. Tracks from that drive recede northward. For scale, the distance between the parallel wheel tracks is about 1 meter (about 40 inches). The terrain in this portion of Mars' Meridiani Planum region includes dark-toned sand ripples and lighter-toned bedrock. This view is presented as a polar projection with geometric seam correction.

  6. Opportunity's View on Sols 1803 and 1804 (Vertical)

    Science.gov (United States)

    2009-01-01

    NASA's Mars Exploration Rover Opportunity used its navigation camera to take the images combined into this full-circle view of the rover's surroundings during the 1,803rd and 1,804th Martian days, or sols, of Opportunity's surface mission (Feb. 18 and 19, 2009). South is at the center; north at both ends. The rover had driven 55 meters on Sol 1803 before beginning to take the frames in this view. Tracks from that drive recede northward. For scale, the distance between the parallel wheel tracks is about 1 meter (about 40 inches). The terrain in this portion of Mars' Meridiani Planum region includes dark-toned sand ripples and lighter-toned bedrock. This view is presented as a vertical projection with geometric seam correction.

  7. Mars climatology from Viking 1 after 20 sols

    Science.gov (United States)

    Hess, S. L.; Henry, R. M.; Greene, G. C.; Leovy, C. B.; Tillman, J. E.; Ryan, J. A.; Chamberlain, T. E.; Cole, H. L.; Dutton, R. G.; Simon, W. E.

    1976-01-01

    Results from the meteorology instruments on the Viking 1 lander are presented for the first 20 sols of operation. The daily patterns of temperature, wind, and pressure have been highly consistent during the period. Hence, these have been assembled into 20-sol composistes and analyzed harmonically. Maximum temperature was 241.8 K and minimum was 187.2 K. The composite wind vector has a mean diurnal magnitude of 2.4 meters per second with prevailing wind from the south and counterclockwise diurnal rotation. Pressure exhibits diurnal and semidiurnal oscillations. The diurnal is ascribed to a combination of effects, and the semidiurnal appears to be the solar semidiurnal tide. Similarities to earth are discussed. A major finding is a continual secular decrease in diurnal mean pressure. This is ascribed to carbon dioxide deposition at the south polar cap.

  8. Profiles and fluctuations in edge and SOL turbulence

    DEFF Research Database (Denmark)

    Naulin, Volker; Xu, G.; Vianello, N.

    2012-01-01

    The time and space averaged profiles of temperature, particle density, and momentum are in the scrape off layer determined by the intermittent transport generated at the edge shear layer. The distinction between profiles and fluctuations becomes arbitrary for situations where the transport...... propagating structures and parallel transport sets up the observed profiles and how intermittency influences edge conditions. The filamentary blob structures also transport and generate currents in the SOL, which can be investigated by means of local magnetic diagnostics. Finally, the ratio of ion to electron...... temperature in the SOL is an important measure for the influence of finite larmor radius effects on the propagation properties of blobs. Numerical investigations indicate that these effects can lead to an increased self confinement and radial reach of these structures. © 2012 WILEY-VCH Verlag GmbH & Co. KGa...

  9. Tribological investigations of sol-gel ceramic films

    Institute of Scientific and Technical Information of China (English)

    张文光; 王成焘; 刘维民

    2002-01-01

    Tribological properties of the TiO2, doped TiO2, AI2O3 and SiO2 thin films prepared by different sol-gel processes are reported. The results indicate that doping deteriorates the wear resistance of TiO2; organic modifier can improve the tribological property of AI2O3 significantly; and the SiO2 film prepared from inorganic salt sodium silicate registers much better wear resistance than that from ethyl orthosilicate.

  10. Mini-SOL Språka och Lek

    DEFF Research Database (Denmark)

    Bylander, Helle Iben

    Ju tidigare man börjar med en medveten språklig stimulering, desto bättre är det. I denna praktiska handbok finns pedagogiska tips och lekar för de allra yngsta barnen (0–3 år). Boken är sprängfull av roliga aktiviteter som alla stimulerar språkutvecklingen. Mini-SOL följer de språkliga områdena ...

  11. Sol-Gel Thin Films for Plasmonic Gas Sensors

    Directory of Open Access Journals (Sweden)

    Enrico Della Gaspera

    2015-07-01

    Full Text Available Plasmonic gas sensors are optical sensors that use localized surface plasmons or extended surface plasmons as transducing platform. Surface plasmons are very sensitive to dielectric variations of the environment or to electron exchange, and these effects have been exploited for the realization of sensitive gas sensors. In this paper, we review our research work of the last few years on the synthesis and the gas sensing properties of sol-gel based nanomaterials for plasmonic sensors.

  12. Tribological investigations of sol-gel ceramic films

    Institute of Scientific and Technical Information of China (English)

    张文光; 刘维民; 王成焘

    2002-01-01

    Tribological properties of the TiO2, doped TiO2, Al2O3 and SiO2 thin films prepared by different sol-gel processes are reported. The results indicate that doping deteriorates the wear resistance of TiO2; organic modifier can improve the tribological property of Al2O3 significantly; and the SiO2 film prepared from inorganic salt sodium silicate registers much better wear resistance than that from ethyl orthosilicate.

  13. COMPARISON OF SOL-GEL SILICATE COATINGS ON Ti SUBSTRATE

    OpenAIRE

    2012-01-01

    The objective of the submitted work was to prepare and to characterize two types of silicate coatings prepared by the sol-gel method using the dip-coating technique on a titanium substrate. Efforts have been made to use mechanical properties of bio-inert titanium and bioactive properties of a silicate layer enriched with an admixture of compounds identified below. The first group consisted of silicate coatings containing silver, brushite and monetite. The other group of silicate coatings cont...

  14. Flow behaviour of gellan sol with selected cations.

    Science.gov (United States)

    Sharma, Shipra; Bhattacharya, Suvendu

    2015-02-01

    An understanding of the flow behaviour of the sols before gel formation is important for developing nutrient enriched gels. The influence of cations like CaCl2 (0.05 and 0.1 %, w/w) and FeSO4 (0.05 and 0.1 %, w/w) on the rheological properties of 1 % gellan sol (w/w) prior to gelling was investigated. The apparent viscosity, reported at a shear-rate of 100 s(-1), indicated that the gellan dispersion without any cation possessed lower values compared to other samples containing different cations. The Cross model provided the best fit (0.97 ≤ r ≤ 0.99, p ≤ 0.01) compared to moderate fitting to power law model (0.94 ≤ r ≤ 0.98). Among the different Cross model parameters, the zero-shear viscosity (ηo) increased with the addition of CaCl2 and FeSO4, and with an increase in their concentrations. Zero-shear viscosity values were 0.46 Pas for gellan sol, 0.79 Pas for gellan with 0.05 % (w/w) CaCl2, 1.41 Pas for gellan with 0.1 % CaCl2, 3.85 Pas for gellan with 0.05 % FeSO4 and 4.33 Pas for gellan with 0.1 % FeSO4. An increase in cation concentration from 0.05 to 0.10 % (w/w) marginally increased the relaxation time (λ) values indicating the development of more solid characteristics in the sol.

  15. Non-hydrolytic sol-gel routes to heterogeneous catalysts

    OpenAIRE

    Debecker, Damien P.; Mutin, P. Hubert

    2012-01-01

    Oxides and mixed oxides have a tremendous importance in the field of heterogeneous catalysis, serving either as catalysts or as supports for active species. The performance of a catalyst depends directly on its composition, texture, structure and surface properties, which have to be precisely controlled and adapted to each application. In this context, the sol-gel process is a unique tool for the preparation and understanding of catalytic materials, owing to its exceptional versatility. In th...

  16. Opportunity Self-Portrait, Sols 322-323

    Science.gov (United States)

    2005-01-01

    NASA's Mars Exploration Rover Opportunity used its panoramic camera to take the images combined into this mosaic view of the rover. The downward-looking view omits the mast on which the camera is mounted. It shows Opportunity's solar panels to be relatively dust-free. The images were taken through the camera's 600-, 530- and 480-nanometer filters during Opportunity's 322nd and 323rd martian days, or sols (Dec. 19 and 20, 2004).

  17. Spirit Self-Portrait, Sols 329-330

    Science.gov (United States)

    2005-01-01

    NASA's Mars Exploration Rover Spirit used its panoramic camera to take the images combined into this mosaic view of the rover. The downward-looking view omits the mast on which the camera is mounted. It shows dust accumulation on Spirit's solar panels. The images were taken through the camera's 600-, 530- and 480-nanometer filters during Spirit's 329th and 330th martian days, or sols (Dec. 7 and 8, 2004).

  18. Mécanique des sols et des roches

    CERN Document Server

    Vullier, Laurent; Zhao, Jian

    2016-01-01

    La mécanique des sols et la mécanique des roches sont des disciplines généralement traitées séparément dans la littérature. Pour la première fois, un traité réunit ces deux spécialités, en intégrant également les connaissances en lien avec les écoulements souterrains et les transferts thermiques. A la fois théorique et pratique, cet ouvrage propose tout d'abord une description détaillée de la nature et de la composition des sols et des roches, puis s'attache à la modélisation de problèmes aux conditions limites et présente les essais permettant de caractériser les sols et les roches, tant d'un point de vue mécanique qu'hydraulique et thermique. La problématique des sols non saturés et des écoulements multiphasiques est également abordée. Une attention particulière est portée aux lois de comportement mécanique et à la détermination de leurs paramètres par des essais in situ et en laboratoire, et l'ouvrage offre également une présentation détaillée des systèmes de classi...

  19. Sol-Gel Synthesis of Non-Silica Monolithic Materials

    Directory of Open Access Journals (Sweden)

    Bartłomiej Gaweł

    2010-04-01

    Full Text Available Monolithic materials have become very popular because of various applications, especially within chromatography and catalysis. Large surface areas and multimodal porosities are great advantages for these applications. New sol-gel preparation methods utilizing phase separation or nanocasting have opened the possibility for preparing materials of other oxides than silica. In this review, we present different synthesis methods for inorganic, non-silica monolithic materials. Some examples of application of the materials are also included.

  20. Bioactive behaviour of sol-gel derived antibacterial bioactive glass

    Energy Technology Data Exchange (ETDEWEB)

    Bellantone, M.; Hench, L.L. [Imperial Coll. of Science, Technology and Medicine, London (United Kingdom). Dept. of Materials

    2001-07-01

    A new four-component bioactive glass containing Ag{sub 2}O was produced via the sol-gel process. This system releases Ag{sup +} which is a powerful antibacterial agent. The work reported herein is a comparative study of the bioactivity levels of conventional bioactive glass and of the new antibacterial glass. On the basis of XRD patterns, FTIR spectra, and ICP data, the bioactive behaviour of the two biomaterials is nearly equivalent. (orig.)

  1. Alumina Coating on Carbon Fibers by Sol-Gel Method

    OpenAIRE

    2006-01-01

    Alumina precursor film was coated on carbon fibers by a sol-gel method using aluminum alkoxide solution. The optimum coating condition for the concentration of alumina alkoxide and silane coupling agent was determined to uniformly coat alumina precursor on carbon fibers. Alumina precursor converted to alumina ceramics by heating at 750℃. SEM and EPMA showed that alumina ceramics was uniformly coated on carbon fibers. The thickness of alumina layer increased with increasing coating times. The ...

  2. Preparation and bioactivity of sol-gel macroporous bioactive glass

    Institute of Scientific and Technical Information of China (English)

    Zhihua Zhou; Jianming Ruan; Jianpeng Zou; Zhongcheng Zhou

    2008-01-01

    Bioactive glass is well known for its ability of bone regeneration, and sol-gel bioactive glass has many advantages com-pared with melt-derived bioactive glass. 3-D scaffold prepared by the sol-gel method is a promising substrate material for bone tissue engineering and large-scale bone repair. Porous sol-gel glass in the CaO-SiO2-P2O5 system with macropores larger than 100 μm was prepared by the addition of stearic acid as a pore former. The diameter of the pore created by the pore former varied from 100 to 300μm. The formation of a hydroxyapatite layer on the glass was analyzed by studying the surface of the porous glass by scanning elec-tron microscopy, energy dispersive spectroscopy, X-ray diffraction, and Raman spectra after they had been immersed in simulated body fluid (SBF) for some time, and the porous glass shows good bioactivity.

  3. The Influence of Microgravity on Silica Sol-Gel Formation

    Science.gov (United States)

    Sibille, L.; Smith, D. D.; Cronise, R.; Hunt, A. J.; Wolfe, D. B.; Snow, L. A.; Oldenberg, S.; Halas, N.; Rose, M. Franklin (Technical Monitor)

    2000-01-01

    We discuss space-flight experiments involving the growth of silica particles and gels. The effect of microgravity on the growth of silica particles via the sol-gel route is profound. In four different recipes spanning a large range of the parameter space that typically produces silica nanoparticles in unit-gravity, low-density gel structures were instead formed in microgravity. The particles that did form were generally smaller and more polydisperse than those grown on the ground. These observations suggest that microgravity reduces the particle growth rate, allowing unincorporated species to form aggregates and ultimately gel. Hence microgravity favors the formation of more rarefied structures, providing a bias towards diffusion-limited cluster-cluster aggregation. These results further suggest that in unit gravity, fluid flows and sedimentation can significantly perturb sol-gel substructures prior to gelation and these deleterious perturbations may be "frozen" into the resulting microstructure. Hence, sol-gel pores may be expected to be smaller, more uniform, and less rough when formed in microgravity.

  4. Magnetization of microorganism cells by sol-gel method

    Institute of Scientific and Technical Information of China (English)

    CHEN Bo; ZHAN TianZhuo; LIAN ZhiYang; ZHANG DeYuan

    2008-01-01

    Microorganism cells could be used as templates during fabrication of magnetic or conductive microstructures in different standard shapes.In this paper,feasibility of magnetizing microorganism cells by sol-gel method,which is to coat cells of Spirulina (a type of natural micro-helical microorganism) with the ferrite (a kind of magnetic material),was discussed and investigated.Then the cell form,compo-nents and the phase structure were observed and analyzed using various tools including optical microscopy,scanning electron microscopy (SEM),energy dis-persive X-ray detector (EDX),transmission electron microscopy (TEM),and X-ray diffraction analysis (XRD).Results showed that spirulina cells could be coated with ferrite after the sol-gel process,with the shape of natural helixes well kept,that the components of different sampling points on the surface layer were consistent and the thickness of layer was uniform,and that the type of the surface ferrite layer formed was cubic Fe304.It was also observed that there were nano-parUcles yielded in the cells and certain deposit on the walls between cells.The kinetics of the cell magnetization technology by sol-gel was also discussed.

  5. Sol-gel Technology and Advanced Electrochemical Energy Storage Materials

    Science.gov (United States)

    Chu, Chung-tse; Zheng, Haixing

    1996-01-01

    Advanced materials play an important role in the development of electrochemical energy devices such as batteries, fuel cells, and electrochemical capacitors. The sol-gel process is a versatile solution for use in the fabrication of ceramic materials with tailored stoichiometry, microstructure, and properties. This processing technique is particularly useful in producing porous materials with high surface area and low density, two of the most desirable characteristics for electrode materials. In addition,the porous surface of gels can be modified chemically to create tailored surface properties, and inorganic/organic micro-composites can be prepared for improved material performance device fabrication. Applications of several sol-gel derived electrode materials in different energy storage devices are illustrated in this paper. V2O5 gels are shown to be a promising cathode material for solid state lithium batteries. Carbon aerogels, amorphous RuO2 gels and sol-gel derived hafnium compounds have been studied as electrode materials for high energy density and high power density electrochemical capacitors.

  6. Magnetization of microorganism cells by sol-gel method

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Microorganism cells could be used as templates during fabrication of magnetic or conductive microstructures in different standard shapes. In this paper, feasibility of magnetizing microorganism cells by sol-gel method, which is to coat cells of Spirulina (a type of natural micro-helical microorganism) with the ferrite (a kind of magnetic material), was discussed and investigated. Then the cell form, components and the phase structure were observed and analyzed using various tools including optical microscopy, scanning electron microscopy (SEM), energy dispersive X-ray detector (EDX), transmission electron microscopy (TEM), and X-ray diffraction analysis (XRD). Results showed that spirulina cells could be coated with ferrite after the sol-gel process, with the shape of natural helixes well kept, that the components of different sampling points on the surface layer were consistent and the thickness of layer was uniform, and that the type of the surface ferrite layer formed was cubic Fe3O4. It was also observed that there were nano-particles yielded in the cells and certain deposit on the walls between cells. The kinetics of the cell magnetization technology by sol-gel was also discussed.

  7. Spirit's View Beside 'Home Plate' on Sol 1823

    Science.gov (United States)

    2009-01-01

    NASA's Mars Exploration Rover Spirit used its navigation camera to take the images that have been combined into this 180-degree view of the rover's surroundings during the 1,823rd Martian day, or sol, of Spirit's surface mission (Feb. 17, 2009). The center of the view is toward the south-southwest. The rover had driven 7 meters (23 feet) eastward earlier on Sol 1823, part of maneuvering to get Spirit into a favorable position for climbing onto the low plateau called 'Home Plate.' However, after two driving attempts with negligible progress during the following three sols, the rover team changed its strategy for getting to destinations south of Home Plate. The team decided to drive Spirit at least partway around Home Plate, instead of ascending the northern edge and taking a shorter route across the top of the plateau. Layered rocks forming part of the northern edge of Home Plate can be seen near the center of the image. Rover wheel tracks are visible at the lower edge. This view is presented as a cylindrical projection with geometric seam correction.

  8. Bright Soil Churned by Spirit's Sol 1861 Drive

    Science.gov (United States)

    2009-01-01

    NASA's Mars Exploration Rover Spirit drove 22.7 meters (74 feet) toward the southwest on the 1,861st Martian day, or sol, of Spirit's mission on Mars (March 28, 2009). After the drive, the rover took this image with its front hazard-avoidance camera, looking back at the tracks from the drive. As usual since losing the use of its right-front wheel in 2006, Spirit drove backwards. The immobile right-front wheel churned up a long stripe of bright soil during this drive. Where Spirit has found such bright soil in the past, subsequent analysis of the composition found concentrations of sulfur or silica that testified to past action of water at the site. When members of the rover team saw the large quantity of bright soil exposed by the Sol 1861 drive, they quickly laid plans to investigate the composition with Spirit's alpha particle X-ray spectrometer. The Sol 1861 drive took the rover past the northwest corner of the low plateau called 'Home Plate,' making progress on a route around the western side of Home Plate. The edge of Home Plate forms the horizon on the right side of this image. Husband Hill is on the horizon on the left side. For scale, the parallel rover wheel tracks are about 1 meter (40 inches) apart. The rover's hazard-avoidance cameras take 'fisheye' wide-angle images.

  9. Spirit's View Beside 'Home Plate' on Sol 1823

    Science.gov (United States)

    2009-01-01

    NASA's Mars Exploration Rover Spirit used its navigation camera to take the images that have been combined into this 180-degree view of the rover's surroundings during the 1,823rd Martian day, or sol, of Spirit's surface mission (Feb. 17, 2009). The center of the view is toward the south-southwest. The rover had driven 7 meters (23 feet) eastward earlier on Sol 1823, part of maneuvering to get Spirit into a favorable position for climbing onto the low plateau called 'Home Plate.' However, after two driving attempts with negligible progress during the following three sols, the rover team changed its strategy for getting to destinations south of Home Plate. The team decided to drive Spirit at least partway around Home Plate, instead of ascending the northern edge and taking a shorter route across the top of the plateau. Layered rocks forming part of the northern edge of Home Plate can be seen near the center of the image. Rover wheel tracks are visible at the lower edge. This view is presented as a cylindrical projection with geometric seam correction.

  10. Dynamics Research on the Gelling Course of Silica Sol

    Institute of Scientific and Technical Information of China (English)

    LUYi-chun; LIZai-geng

    1995-01-01

    Dreipping electrolytes into silica sol ,gelling reaction will occur,The research indicates:this is a complicated physicemistry course,which consists of a pre-reaction and a polymerizaion,The former controls the whole course,and in which electronic layers of the sol's particles be-come more and more thiner,but with incresing of the sol concentration,its control force will be diminished ,till the fast-coagulation ,the gelling couse becomes o-controlled,The latter is an in-finite polymeric chani-reaction.The result of gelatination is to produce a very big plymeric molecule-gel,which involves in all space,includes all water ,and its molecular weight is in-definite big.The researh also indicates:the dy-namic course of the gelling could be described quantitaively by an experience formula:lgt=-nlgc+B,All of the characteristic values have definite physical meaning,Electronic value of the contrary-inos is the biggest influential factor ,the natures of the contrary-ions and the natures of the same-electronic-inos have a few influential forces on the characteristic values,The temperature increasing makes the gelling reaction fast.

  11. Retraction statement: Dynamics of Cytochrome C Oxidase Activity in Acute Ischemic Stroke' by Selaković, V.M., Jovanović, M.D., Mihajlović, R.R. and Radenović, L.L.J.

    Science.gov (United States)

    2016-10-01

    The above article from Acta Neurologica Scandinavica, published online on 7 April 2005 in Wiley Online Library (wileyonlinelibrary.com) and in Volume 111, pp. 329-332, has been retracted by agreement between the journal Editor in Chief, Professor Elinor Ben-Menachem, and John Wiley & Sons Ltd. The article has been retracted because a similar article had previously been published in the Jugoslovenska medicinska biohemija in 2003. The authors presumed that since the journal was no longer existing, they felt the need to re-publish their work in Acta Neuorologica Scandinavica. However, in the consideration of the Journal, this constitutes dual publication. References SelakovićVM, JovanovićMD, MihajlovićR, RadenovićLLJ. Cytochrome c oxidase in patients with acute ischaemic brain disease. Jugoslovenska medicinska biohemija. 2003;22:329-334. SelakovićVM, JovanovićMD, MihajlovićRR, RadenovićLLJ. Dynamics of cytochrome c oxidase activity in acute ischemic stroke. Acta Neurol Scand. 2005;111:329-332.

  12. RELATIONS PLANTE/SOL/CLIMAT Connaître le sol : nouveaux enjeux pour la gestion des territoires ruraux

    Directory of Open Access Journals (Sweden)

    Stengel Pierre

    2000-11-01

    Full Text Available Dans son acception commune, le mot sol désigne de façon souvent indissociable l’espace d’un territoire et la terre qui le recouvre. Cet héritage culturel d’une époque encore proche où l’association territoire-espace rural-agriculture relevait de l’évidence pour notre civilisation suffirait à motiver qu’une analyse actualisée des relations agriculture-territoire s’intéresse au sol comme composante de ces relations. Cependant, l’évolution de l’agriculture durant ces dernières décennies a considérablement atténué sa dépendance au sol, en tant qu’objet physique ou matériau déterminant par ses aptitudes et limitations les systèmes et techniques d’exploitation. Un des objectifs prioritaires du développement du modèle dit productiviste de l’agriculture française dans la deuxième moitié de ce siècle a en effet consisté à surmonter les contraintes que le sol imposait à la production. Il y est très largement parvenu. L’usage massif des intrants, engrais et amendements lui a permis de s’affranchir de la dépendance à l’égard de la « fertilité naturelle » des sols. Par la mécanisation et les opérations d’aménagement, drainage, irrigation, remembrement, les limitations physiques ont été largement surmontées. Ces évolutions ont coïncidé avec une spécialisation des systèmes de culture répondant aux exigences de compétitivité économique, qu’elles ont contribué à rendre possible. La réduction du nombre des espèces cultivées qui en est résultée au niveau des exploitations et de régions entières a également restreint la diversité des réponses adaptatives de l’agriculture aux variations spatiales des caractéristiques du sol. Globalement, le succès de l’intensification a permis à l’agriculture d’oublier le sol et de s’approcher d’une situation idéale quant à l’efficacité quantitative du processus productif qui consiste à le traiter comme un mat

  13. SOCIO-DKMOGRAPHIC AND REPRODUC II VL ...

    African Journals Online (AJOL)

    2002-04-04

    Apr 4, 2002 ... Subjects were recruited after the study had been explained to them and ... date, or, if the patient had an ultrasound scan dating before the sixth week. .... schooling for the subjects with a history of induced-abortion was 8.9 ...

  14. DEPRElVl KlJVVı

    Directory of Open Access Journals (Sweden)

    Hüseyin KASAP

    2003-08-01

    Full Text Available B u ç a l ış nıada , dep rem yükleri al t ı ndaki 4,6, 8 ve 10 katlı perdeli-çerçeveli 3 ayrı tip binanınperde e nkesi t değişinlinin sisteınin kesıne kuvYetidağ ı lı ını na etkisi incelenntiştir.Döşeme kalı n lı ğ ı, döşeme ağırlığı, kiriş a ğ ı r l ığı ,perde a ğırlığ ı duvar a ğır lı ğı ve bunlara b ağlıolarak kolon boyutu ta yi n e dil ıni ş ti r .Kolonboyutlarına bağlı olarak kat ağıı4hkları t ay inedilnıiştir.Hesaplanan kat a ğ ır lı kl a rı ile ta b ankesme kuv,

  15. Photochromic organic-inorganic composite materials prepared by sol-gel processing : properties and potentials

    OpenAIRE

    Hou, Lisong; Mennig, Martin; Schmidt, Helmut K.

    1994-01-01

    The sol-gel method which features a low-temperature wet-chemical process opens vast possibilities to incorporating organic dyes into solid matrices for various optical applications. In this paper we present our experimental results on the sol-gel derived photochromic organic-inorganic composite (ORMOCER) materials follwoing an introductory description of the sol-gel process and a brief review on the state of the art of the photochromic solids prepared using this method. Our photochromic spiro...

  16. Ultraviolet Spectrum of Nanometer Zinc Oxide Prepared by Sol-Gel Process

    Institute of Scientific and Technical Information of China (English)

    Xiaoping Liang; Xiaohui Wang; Shaobo Xin; Yajin Liu

    2006-01-01

    Zinc oxide nanometer powders were prepared by the sol-gel process. The sol and the powders characteristic of absorbing ultraviolet light is detected by the ultraviolet spectrometer. The results indicate the concentration of zinc acetate dihydrate in isopropyl alcohol solution and the final pH value of the aqueous sol have effect on the UV absorption of the sol.The nanometer zinc oxide has strong absorption at 200 nm~360 nm, and over 90% ultraviolet in the range of 200 nm~360 nm wavelength are absorbed. The characteristic of absorbing ultraviolet light of zinc oxide increases as the particle size of zinc oxide decreases.

  17. verve, 29 - 2016. Revista do NU-SOL – Núcleo de Sociabilidade Libertária

    Directory of Open Access Journals (Sweden)

    REA Editor

    2016-07-01

    Full Text Available Revista do NU-SOL – Núcleo de Sociabilidade Libertária Programa de Estudos Pós-Graduados em Ciências Sociais PUC-SP Site: http://www.nu-sol.org/verve/verveview1.php?id=33 contato: nu-sol@nu-sol.org jean genet, salete oliveira, jaime cubero, rafael cid, acácio augusto, léon felipe, thiago rodrigues & gustavo simões, john cage, dossiê emma goldman, flávia lucchesi, edson passetti

  18. Spirit's View Beside 'Home Plate' on Sol 1823 (Stereo)

    Science.gov (United States)

    2009-01-01

    [figure removed for brevity, see original site] Left-eye view of a color stereo pair for PIA11971 [figure removed for brevity, see original site] Right-eye view of a color stereo pair for PIA11971 NASA's Mars Exploration Rover Spirit used its navigation camera to take the images that have been combined into this stereo, 180-degree view of the rover's surroundings during the 1,823rd Martian day, or sol, of Spirit's surface mission (Feb. 17, 2009). This view combines images from the left-eye and right-eye sides of the navigation camera. It appears three-dimensional when viewed through red-blue glasses with the red lens on the left. The center of the view is toward the south-southwest. The rover had driven 7 meters (23 feet) eastward earlier on Sol 1823, part of maneuvering to get Spirit into a favorable position for climbing onto the low plateau called 'Home Plate.' However, after two driving attempts with negligible progress during the following three sols, the rover team changed its strategy for getting to destinations south of Home Plate. The team decided to drive Spirit at least partway around Home Plate, instead of ascending the northern edge and taking a shorter route across the top of the plateau. Layered rocks forming part of the northern edge of Home Plate can be seen near the center of the image. Rover wheel tracks are visible at the lower edge. This view is presented as a cylindrical-perspective projection with geometric seam correction.

  19. Spirit's View Beside 'Home Plate' on Sol 1823 (Stereo)

    Science.gov (United States)

    2009-01-01

    [figure removed for brevity, see original site] Left-eye view of a color stereo pair for PIA11971 [figure removed for brevity, see original site] Right-eye view of a color stereo pair for PIA11971 NASA's Mars Exploration Rover Spirit used its navigation camera to take the images that have been combined into this stereo, 180-degree view of the rover's surroundings during the 1,823rd Martian day, or sol, of Spirit's surface mission (Feb. 17, 2009). This view combines images from the left-eye and right-eye sides of the navigation camera. It appears three-dimensional when viewed through red-blue glasses with the red lens on the left. The center of the view is toward the south-southwest. The rover had driven 7 meters (23 feet) eastward earlier on Sol 1823, part of maneuvering to get Spirit into a favorable position for climbing onto the low plateau called 'Home Plate.' However, after two driving attempts with negligible progress during the following three sols, the rover team changed its strategy for getting to destinations south of Home Plate. The team decided to drive Spirit at least partway around Home Plate, instead of ascending the northern edge and taking a shorter route across the top of the plateau. Layered rocks forming part of the northern edge of Home Plate can be seen near the center of the image. Rover wheel tracks are visible at the lower edge. This view is presented as a cylindrical-perspective projection with geometric seam correction.

  20. Evolution of the SOL plasma background at density shoulder formation

    Energy Technology Data Exchange (ETDEWEB)

    D' Isa, Federico Antonio; Carralero, Daniel; Lunt, Tilmann; Collaboration: ASDEX Upgrade Team

    2016-12-15

    One of the main problems of our age is the ever increasing demand of energy. This prompts the search for new energy sources which should have the advantages of being nearly inexhaustible and usable to produce a predictable amount of energy. A possible solution is to build a reactor based on nuclear fusion. ITER will be the first divertor Tokamak to reach fusion break even and it will pave the way to a commercial use of fusion to produce sustainable and clean energy. One of the biggest obstacles to the construction of a commercial fusion reactor is represented by the heat and particle flux toward the main chamber plasma facing components and the divertor targets. A fusion reactor will likely experience power loads and erosion on the verge of the technical limits of available plasma facing materials. To predict properly the distribution of those fluxes between the divertor and the main chamber, a better understanding of the physics in the open field lines region (called Scrape-off layer or SOL) is required. This thesis, being developed in partnership with the Max-Planck-institut fuer Plasmaphysik (Garching bei Muenchen, DE), is framed in this context. In the SOL of L-mode (low confinement) discharges, qualitatively two kinds of density profiles can be distinguished. The first one is characterized by a strong density gradient in the vicinity of the separatrix, followed by a flat region towards the far SOL. The second profile lacks such a strong gradient and displays an almost linear decay in the whole SOL. The latter kind of density profile is characterized by stronger fluxes toward the first wall with respect to the first kind. This my be a threat for the ITER unlike the divertor targets which are made of tungsten, the first wall will be made beryllium which can suffer damage from sputtering. This work is focused on understanding the physics behind the transition between those two profiles, the so-called density shoulder formation. After the shoulder formation it is

  1. Recubrimientos de hidroxiapatita preparados mediante un proceso sol-gel

    Directory of Open Access Journals (Sweden)

    Peón, E.

    2005-12-01

    Full Text Available Hydroxyapatite coatings (HAp have been obtained starting from precursors of sol-gel type. The coatings previously oxidized were deposited on metal surfaces of a based on iron alloy so-called MA956. The alloys were at high temperatures, in order to improve the adhesion with the hydroxyapatite coatings. The sol-gel coating was obtained applying an aqueous route, using triethyl phosphite and aqueous calcium nitrate, as precursors of phosphorous and calcium, respectively. Different sintering thermal treatments were applied on the resulting gels in order to obtain a homogeneous, adherent and crystalline hydroxyapatite coating. The characterization techniques used for this study were optical microscopy, SEM/EDX, XDR and FTIR. Moreover, the adhesion between the hydroxylapatite coating and the substrate was assessed according to the ASTM D 3359-02 standard test method. The results of this study showed that the best thermal treatment is obtained for a sintering temperature of 550 °C during a time of 72 h.

    Se han preparado nuevos recubrimientos de hidroxiapatita (HAp obtenidos a partir de precursores de tipo sol-gel, depositados sobre sustratos metálicos de una aleación de base hierro denominada MA956, previamente oxidados a elevadas temperaturas, para mejorar la adherencia con los recubrimientos de hidroxiapatita. El recubrimiento sol-gel se obtuvo aplicando una ruta acuosa, utilizando como precursores del fósforo y del calcio trietilfosfito y nitrato cálcico tetrahidratado, respectivamente. Sobre los geles resultantes se aplicaron distintos tratamientos térmicos de sinterización, hasta la obtención de recubrimientos de hidroxiapatita homogéneos, adherentes y cristalinos. Las técnicas de caracterización utilizadas para realizar este estudio han sido microscopía óptica, MBE/EDX, DRX y FTIR. Así mismo, se ha determinado la adherencia entre el substrato y el recubrimiento de hidroxiapatita según la norma ASTM D 3359-02. Los resultados

  2. Modified sol-gel coatings for biotechnological applications

    Energy Technology Data Exchange (ETDEWEB)

    Beganskiene, A [Department of General and Inorganic Chemistry, Vilnius University, Vilnius LT-03225 (Lithuania); Raudonis, R [Department of General and Inorganic Chemistry, Vilnius University, Vilnius LT-03225 (Lithuania); Jokhadar, S Zemljic [Faculty of Medicine, Institute of Biophysics, Lipiceva 2, Ljubljana SI-1000 (Slovenia); Batista, U [Faculty of Medicine, Institute of Biophysics, Lipiceva 2, Ljubljana SI-1000 (Slovenia); Kareiva, A [Department of General and Inorganic Chemistry, Vilnius University, Vilnius LT-03225 (Lithuania)

    2007-12-15

    The modified sol-gel derived silica coatings were prepared and characterized. The amino and methyl groups were introduced onto the colloidal silica. The silica coatings with different wettability properties: coloidal silica (water contact angle 17 deg.), polysiloxane (61 deg.), methyl-modified (158 deg. and 46 deg.) coatings samples were tested for CaCo-2 cells proliferation. Methyl-modified coating (46 deg.) proved to be the best substrate for cell proliferation. CaCo-2 cell proliferation two days post seeding was significantly faster on almost laminine, fibronectin and collagen-1 coated samples compared to corresponding controls.

  3. Synthesis of lithium doped zinc oxide by sol gel

    Science.gov (United States)

    MEZIANE, K.; ELHICHOU, A.; ELHAMIDI, A.; ALMAGGOUSSI, A.; CHHIBA, M.

    2016-10-01

    Li-doped ZnO thin films were prepared by sol-gel method and deposed on glass substrate using spin coating technique. The effects of Li on structural and optical properties were investigated. The X-ray diffraction (XRD) analysis reveals that Li incorporation leads to the great improvement of the crystalline quality of ZnO thin films. Scanning electron microscopy (SEM) images showed that nanowires are aligned nearly perpendicular to the substrate plane and are affected significantly by Li incorporation. The optical transmission of the films was higher than 80% in the visible region. It is found that the optical gap and the refractive index remain practically constant.

  4. Titanium (IV) sol-gel chemistry in varied gravity environments

    Science.gov (United States)

    Hales, Matthew; Martens, Wayde; Steinberg, Theodore

    Sol-gel synthesis in reduced gravity is a relatively new topic in the literature and further inves-tigation is essential to realise its potential and application to other sol-gel systems. The sol-gel technique has been successfully applied to the synthesis of silica systems of varying porosity for many diverse applications [1-5]. It is proposed that current methods for the synthesis of silica sol-gels in reduced gravity may be applied to titanium sol-gel processing in order to enhance desirable physical and chemical characteristics of the final materials. The physical and chemical formation mechanisms for titanium alkoxide based sol-gels, to date, is not fully understood. However, various authors [6-9] have described potential methods to control the hydrolysis and condensation reactions of titanium alkoxides through the use of chemical inhibitors. A preliminary study of the reaction kinetics of titanium alkoxide sol-gel reaction in normal gravity was undertaken in order to determine reactant mixtures suitable for further testing under varied gravity conditions of limited duration. Through the use of 1H Nuclear Magnetic Resonance spectroscopy (NMR) for structural analysis of precursor materials, Ultra-Violet-Visible spectroscopy (UV-VIS) and viscosity measurements, it was demonstrated that not only could the rate of the chemical reaction could be controlled, but directed linear chain growth within the resulting gel structure was achievable through the use of increased inhibitor concentrations. Two unique test systems have been fabricated to study the effects of varied gravity (reduced, normal, high) on the formation of titanium sol-gels. Whilst the first system is to be used in conjunction with the recently commissioned drop tower facility at Queensland University of Technology in Brisbane, Australia to produce reduced gravity conditions. The second system is a centrifuge capable of providing high gravity environments of up to 70 G's for extended periods of time

  5. 虚拟机宿主服务器及其性能收集方法研究%Research of VM-hosted servers and performance collecting methods

    Institute of Scientific and Technical Information of China (English)

    薛青; 张延园

    2009-01-01

    介绍了虚拟化技术的概念和研究范围,接着探讨计算平台虚拟化及高可用等特性,引入虚拟机宿主服务器的概念,指出为了发挥虚拟化技术的特性,对虚拟机宿主服务器进行性能数据收集的必要性,以EsxServer和Xen为性能收集对象,分别探讨性能收集方法.具体方法是针对不同虚拟化产品,相应使用了Linux命令查询解析、虚拟化监视器命令解析及数据管理对象访问.最后以虚拟化产品厂商提供的性能监视数据作为参照,指出了性能收集方法的优劣.%The virtualization technology is introduced including its conception and research range. The computing platform virtualization is discussed later, involving the term VM-hosted servers. Then the necessity is pointed out which emphasized to collect performance information from VM-hosted servers to take advantage of features of virtualization. After that the information gathering methods for Esx Server and Xen are discussed, such as query and analysis by Linux command, analysis by VMM command and data management objects access. According to the data from tools of virtualization products manufactures, the Pros and Cons of these implied methods are analyzed.

  6. Le sol et l’eau, un couple : Connaître et gérer les sols pour préserver l’eau

    OpenAIRE

    Dorfliger, Nathalie; Gascuel Odoux, Chantal

    2014-01-01

    National audience; Le sol joue un rôle majeur dans le cycle de l’eau,assurant le partage entre infiltration et ruissellementavec des conséquences sur la qualité et le tempsde transfert de l’eau. Le sol régule les transferts d’eauentre l’atmosphère, le sous-sol et la surface, et constitueun réservoir pour les écosystèmes terrestres. Intégrer l’étathydrique et les propriétés physiques des sols est importantdans les modèles de gestion de l’eau et de prévisiondes phénomènes de sécheresse et d’ino...

  7. Processing and Characterization of Sol-Gel Cerium Oxide Microspheres

    Energy Technology Data Exchange (ETDEWEB)

    McClure, Zachary D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Padilla Cintron, Cristina [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2016-09-27

    Of interest to space exploration and power generation, Radioisotope Thermoelectric Generators (RTGs) can provide long-term power to remote electronic systems without the need for refueling or replacement. Plutonium-238 (Pu-238) remains one of the more promising materials for thermoelectric power generation due to its high power density, long half-life, and low gamma emissions. Traditional methods for processing Pu-238 include ball milling irregular precipitated powders before pressing and sintering into a dense pellet. The resulting submicron particulates of Pu-238 quickly accumulate and contaminate glove boxes. An alternative and dust-free method for Pu-238 processing is internal gelation via sol-gel techniques. Sol-gel methodology creates monodisperse and uniform microspheres that can be packed and pressed into a pellet. For this study cerium oxide microspheres were produced as a surrogate to Pu-238. The similar electronic orbitals between cerium and plutonium make cerium an ideal choice for non-radioactive work. Before the microspheres can be sintered and pressed they must be washed to remove the processing oil and any unreacted substituents. An investigation was performed on the washing step to find an appropriate wash solution that reduced waste and flammable risk. Cerium oxide microspheres were processed, washed, and characterized to determine the effectiveness of the new wash solution.

  8. Formation of Ultrafine Apatite Fibers by Sol-gel/Electrospinning

    Institute of Scientific and Technical Information of China (English)

    DING Ya-mei; YUAN Xiao-yan; ZHAO Jin; GUO Wan-chun; WANG Xiu-kui

    2007-01-01

    Ultrafine apatite fibers were prepared by electrospinning of sol-gel precursor/poly(vinyl pyrrolidone)(PVP) solutions followed by subsequent calcination. The as-electrospun and calcinated fibers were observed under a scanning electron microscope and an optical polarizing microscope. Results show that the morphology and the diameter of as-electrospun fibers strongly depend on the viscosity and the surface tension of sol-gel precursor/PVP solutions. After calcination, the smooth as-electrospun fibers shrink and the fiber diameter decreases because of the removal of the polymer. The chemical evolution upon the transformation of the precursor from a gel to the final apatite fibers was investigated by thermogravimetric-differential thermal analysis, X-ray diffraction, and Fourier transform infrared spectroscopy. It is thus suggested that the crystalline structure of the calcined fibers is largely influenced by the calcination temperature. After being calcined at 600 ℃, the apatite fibers with a diameter of about 280 nm containing β-tricalcium phosphate were obtained.

  9. Ultrafast Sol-Gel Synthesis of Graphene Aerogel Materials

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Mathew; Hu, Matthew; Manandhar, Sandeep; Sakshaug, Avery; Strong, Adam; Riley, Leah; Pauzauskie, Peter J.

    2015-12-01

    Graphene aerogels derived from graphene-oxide (GO) starting materials recently have been shown to exhibit a combination of high electrical conductivity, chemical stability, and low cost that has enabled a range of electrochemical applications. Standard synthesis protocols for manufacturing graphene aerogels require the use of sol-gel chemical reactions that are maintained at high temperatures for long periods of time ranging from 12 hours to several days. Here we report an ultrafast, acid-catalyzed sol-gel formation process in acetonitrile in which wet GO-loaded gels are realized within 2 hours at temperatures below 45°C. Spectroscopic and electrochemical analysis following supercritical drying and pyrolysis confirms the reduction of the GO in the aerogels to sp2 carbon crystallites with no residual carbon–nitrogen bonds from the acetonitrile or its derivatives. This rapid synthesis enhances the prospects for large-scale manufacturing of graphene aerogels for use in numerous applications including sorbents for environmental toxins, support materials for electrocatalysis, and high-performance electrodes for electrochemical capacitors and solar cells.

  10. Sol-gel based sensor for selective formaldehyde determination.

    Science.gov (United States)

    Bunkoed, Opas; Davis, Frank; Kanatharana, Proespichaya; Thavarungkul, Panote; Higson, Séamus P J

    2010-02-01

    We report the development of transparent sol-gels with entrapped sensitive and selective reagents for the detection of formaldehyde. The sampling method is based on the adsorption of formaldehyde from the air and reaction with beta-diketones (for example acetylacetone) in a sol-gel matrix to produce a yellow product, lutidine, which was detected directly. The proposed method does not require preparation of samples prior to analysis and allows both screening by visual detection and quantitative measurement by simple spectrophotometry. The detection limit of 0.03 ppmv formaldehyde is reported which is lower than the maximum exposure concentrations recommended by both the World Health Organisation (WHO) and the Occupational Safety and Health Administration (OSHA). This sampling method was found to give good reproducibility, the relative standard deviation at 0.2 and 1 ppmv being 6.3% and 4.6%, respectively. Other carbonyl compounds i.e. acetaldehyde, benzaldehyde, acetone and butanone do not interfere with this analytical approach. Results are provided for the determination of formaldehyde in indoor air.

  11. After Rasping by Phoenix in 'Snow White' Trench, Sol 60

    Science.gov (United States)

    2008-01-01

    NASA's Phoenix Mars Lander used the motorized rasp on the back of its robotic arm scoop during the mission's 60th Martian day, or sol, (July 26, 2008) to penetrate a hard layer at the bottom of a trench informally called 'Snow White.' This view, taken by the lander's Surface Stereo Imager and presented in approximately true color, shows the trench later the same sol. Most of the 16 holes left by a four-by-four array of rasp placements are visible in the central area of the image. A total 3 cubic centimeters, or about half a teaspoon, of material was collected in the scoop. Material in the scoop was collected both by the turning rasp, which threw material into the scoop through an opening at the back of the scoop, and by the scoop's front blade, which was run over the rasped area to pick up more shavings. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  12. Novel hybrid sol-gel materials for smart sensor windows

    Science.gov (United States)

    Wencel, Dorota; Higgins, Clare; Guckian, Adrian; McDonagh, Colette; MacCraith, Brian D.

    2005-06-01

    Current sensor trends, such as multianalyte capability, miniaturisation and patternability are important drivers for materials requirements in optical chemical sensors. In particular, issues such as enhanced sensitivity and printablity are key in developing optimised sensor materials for smart windows for bioprocessing applications. This study focuses on combining novel sol-gel-based hybrid matrices with engineered luminescent complexes to produce stable luminescence-based optical sensors with enhanced sensitivity for a range of analytes including oxygen, pH and carbon dioxide. As well as optimising sensor performance, issues such as surface modification of the plastic substrate and compatibility with different deposition techniques were addressed. Hybrid sol-gel matrices were developed using a range of precursors including tetraethoxysilane (TEOS), methyltriethoxysilane (MTEOS), ethyltriethoxysilane (ETEOS), n-propyltriethoxysilane (PTEOS), phenyltriethoxysilane (PhTEOS), and n-octyltriethoxysilane (C8TEOS). Oxygen sensing, based on luminescence quenching of ruthenium phenanthroline complexes, has been realised with each of these hybrid materials. Furthermore, the possibility of immobilising pH-indicators for pH and carbon dioxide sensing has been investigated with some success. In the context of in-situ monitoring of bioprocesses, issues such as humidity interference as well as the chemical robustness of the multianalyte platform, were addressed.

  13. Profiles and fluctuations in Edge and SOL turbulence

    Energy Technology Data Exchange (ETDEWEB)

    Naulin, V.; Madsen, J.; Nielsen, A.H.; Rasmussen, J.J. [Association Euratom DTU, Technical University of Denmark, Roskilde (Denmark); Xu, G. [Chinese Academy of Science, Inst. Plasma Phys, Hefei (China); Vianello, N. [Consorzio RFX, Associazione EURATOM-ENEA sulla Fusione, Padova (Italy); Schrittwieser, R.; Ionita, C.; Maszl, C.; Mehlmann, F. [Innsbruck University, Inst Ion Phys and Applied Phys., Assoc. EURATOM OeAW, Innsbruck (Austria); Yan, N. [Association Euratom DTU, Technical University of Denmark, Roskilde (Denmark); Chinese Academy of Science, Inst. Plasma Phys, Hefei (China)

    2012-06-15

    The time and space averaged profiles of temperature, particle density, and momentum are in the scrape off layer determined by the intermittent transport generated at the edge shear layer. The distinction between profiles and fluctuations becomes arbitrary for situations where the transport is highly intermittent and shows long range correlations. Without this distinction the full range in parameter variability has to be taken into account for simulations, posing extreme demands on the used models. Numerical investigations and experimental results show how the interplay between radially propagating structures and parallel transport sets up the observed profiles and how intermittency influences edge conditions. The filamentary blob structures also transport and generate currents in the SOL, which can be investigated by means of local magnetic diagnostics. Finally, the ratio of ion to electron temperature in the SOL is an important measure for the influence of finite larmor radius effects on the propagation properties of blobs. Numerical investigations indicate that these effects can lead to an increased self confinement and radial reach of these structures (copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  14. Dust Devil in Spirit's View Ahead on Sol 1854 (Stereo)

    Science.gov (United States)

    2009-01-01

    [figure removed for brevity, see original site] Left-eye view of a color stereo pair for PIA11960 [figure removed for brevity, see original site] Right-eye view of a color stereo pair for PIA11960 NASA's Mars Exploration Rover Spirit used its navigation camera to take the images that have been combined into this stereo, 180-degree view of the rover's surroundings during the 1,854th Martian day, or sol, of Spirit's surface mission (March 21, 2009). This view combines images from the left-eye and right-eye sides of the navigation camera. It appears three-dimensional when viewed through red-blue glasses with the red lens on the left. The rover had driven 13.79 meters (45 feet) westward earlier on Sol 1854. West is at the center, where a dust devil is visible in the distance. North on the right, where Husband Hill dominates the horizon; Spirit was on top of Husband Hill in September and October 2005. South is on the left, where lighter-toned rock lines the edge of the low plateau called 'Home Plate.' This view is presented as a cylindrical-perspective projection with geometric seam correction.

  15. View Ahead After Spirit's Sol 1861 Drive (Stereo)

    Science.gov (United States)

    2009-01-01

    [figure removed for brevity, see original site] Left-eye view of a color stereo pair for PIA11977 [figure removed for brevity, see original site] Right-eye view of a color stereo pair for PIA11977 NASA's Mars Exploration Rover Spirit used its navigation camera to take the images combined into this stereo, 210-degree view of the rover's surroundings during the 1,861st to 1,863rd Martian days, or sols, of Spirit's surface mission (March 28 to 30, 2009). This view combines images from the left-eye and right-eye sides of the navigation camera. It appears three-dimensional when viewed through red-blue glasses with the red lens on the left. The center of the scene is toward the south-southwest. East is on the left. West-northwest is on the right. The rover had driven 22.7 meters (74 feet) southwestward on Sol 1861 before beginning to take the frames in this view. The drive brought Spirit past the northwestern corner of Home Plate. In this view, the western edge of Home Plate is on the portion of the horizon farthest to the left. A mound in middle distance near the center of the view is called 'Tsiolkovsky' and is about 40 meters (about 130 feet) from the rover's position. This view is presented as a cylindrical-perspective projection with geometric seam correction.

  16. miSolRNA: A tomato micro RNA relational database

    Directory of Open Access Journals (Sweden)

    Fernie Alisdair R

    2010-11-01

    Full Text Available Abstract Background The economic importance of Solanaceae plant species is well documented and tomato has become a model for functional genomics studies. In plants, important processes are regulated by microRNAs (miRNA. Description We describe here a data base integrating genetic map positions of miRNA-targeted genes, their expression profiles and their relations with quantitative fruit metabolic loci and yield associated traits. miSolRNA provides a metadata source to facilitate the construction of hypothesis aimed at defining physiological modes of action of regulatory process underlying the metabolism of the tomato fruit. Conclusions The MiSolRNA database allows the simple extraction of metadata for the proposal of new hypothesis concerning possible roles of miRNAs in the regulation of tomato fruit metabolism. It permits i to map miRNAs and their predicted target sites both on expressed (SGN-UNIGENES and newly annotated sequences (BAC sequences released, ii to co-locate any predicted miRNA-target interaction with metabolic QTL found in tomato fruits, iii to retrieve expression data of target genes in tomato fruit along their developmental period and iv to design further experiments for unresolved questions in complex trait biology based on the use of genetic materials that have been proven to be a useful tools for map-based cloning experiments in Solanaceae plant species.

  17. Sol-gel derived ceramic electrolyte films on porous substrates

    Energy Technology Data Exchange (ETDEWEB)

    Kueper, Timothy Walter [Univ. of California, Berkeley, CA (United States)

    1992-05-01

    A process for the deposition of sol-gel derived thin films on porous substrates has been developed; such films should be useful for solid oxide fuel cells and related applications. Yttria-stabilized zirconia films have been formed from metal alkoxide starting solutions. Dense films have been deposited on metal substrates and ceramic substrates, both dense and porous, through dip-coating and spin-coating techniques, followed by a heat treatment in air. X-ray diffraction has been used to determine the crystalline phases formed and the extent of reactions with various substrates which may be encountered in gas/gas devices. Surface coatings have been successfully applied to porous substrates through the control of substrate pore size and deposition parameters. Wetting of the substrate pores by the coating solution is discussed, and conditions are defined for which films can be deposited over the pores without filling the interiors of the pores. Shrinkage cracking was encountered in films thicker than a critical value, which depended on the sol-gel process parameters and on the substrate characteristics. Local discontinuities were also observed in films which were thinner than a critical value which depended on the substrate pore size. A theoretical discussion of cracking mechanisms is presented for both types of cracking, and the conditions necessary for successful thin formation are defined. The applicability of these film gas/gas devices is discussed.

  18. Sol - Gel synthesis and characterization of magnesium peroxide nanoparticles

    Science.gov (United States)

    Jaison, J.; Ashok raja, C.; Balakumar, S.; Chan, Y. S.

    2015-04-01

    Magnesium peroxide is an excellent source of oxygen in agriculture applications, for instance it is used in waste management as a material for soil bioremediation to remove contaminants from polluted underground water, biological wastes treatment to break down hydrocarbon, etc. In the present study, sol-gel synthesis of magnesium peroxide (MgO2) nanoparticles is reported. Magnesium peroxide is odourless; fine peroxide which releases oxygen when reacts with water. During the sol-gel synthesis, the magnesium malonate intermediate is formed which was then calcinated to obtain MgO2 nanoparticles. The synthesized nanoparticles were characterized using Thermo gravimetric -Differential Thermal Analysis (TG- DTA), X-Ray Diffraction studies (XRD) and High Resolution Transmission Electron Microscope (HRTEM). Our study provides a clear insight that the formation of magnesium malonate during the synthesis was due to the reaction between magnesium acetate, oxalic acid and ethanol. In our study, we can conclude that the calcination temperature has a strong influence on particle size, morphology, monodispersity and the chemistry of the particles.

  19. Nanostructured Energetic Materials with Sol-Gel Methods

    Energy Technology Data Exchange (ETDEWEB)

    Gash, A; Satcher, J; Simpson, R; Clapsaddle, B

    2003-11-25

    The utilization of sol-gel chemical methodology to prepare nanostructured energetic materials as well as the concepts of nanoenergetics is described. The preparation and characterization of two totally different compositions is detailed. In one example, nanostructured aerogel and xerogel composites of sol-gel iron (III) oxide and ultra fine grained aluminum (UFG Al) are prepared, characterized, and compared to a conventional micron-sized Fe{sub 2}O{sub 3}/Al thermite. The exquisite degree of mixing and intimate nanostructuring of this material is illustrated using transmission and scanning electron microscopies (TEM and SEM). The nanocomposite material has markedly different energy release (burn rate) and thermal properties compared to the conventional composite, results of which will be discussed. Small-scale safety characterization was performed aerogels and xerogels of the nanostructured thermite. The second nanostructured energetic material consists of a nanostructured hydrocarbon resin fuel network with fine ammonium perchlorate (NH{sub 4}ClO{sub 4}) oxidizer present.

  20. The primary electroviscous effect of prolate silica sols.

    Science.gov (United States)

    Rasmusson, Mikael; Allison, Stuart; Wall, Staffan

    2003-04-15

    The intrinsic viscosity and the dynamic mobility of four silica sols have been measured as a function of the ionic strength. It was found that intrinsic viscosity decreased with increasing ionic strength, which we attribute to the primary electroviscous effect. The geometry and the charge of the particles were fitted using experimental viscosity, light scattering, and dynamic mobility data, where the intrinsic viscosity measured at the highest ionic strength for a given sol was used as input data in our analysis. Further, the boundary element (BE) method was used to calculate the primary electroviscous effect and electrophoretic mobility of charged prolate ellipsoids. These calculations were then compared with experimental data, and the primary electroviscous effect was subtracted from the intrinsic viscosity at a given ionic strength, which led to a slightly altered geometry of the particles. This revised geometry was used as input data using the BE method, and the procedure was repeated iteratively until agreement was obtained at high ionic strength. In general, good agreement between theory and experiment was found.

  1. Opportunity's View on Sols 1803 and 1804 (Stereo)

    Science.gov (United States)

    2009-01-01

    [figure removed for brevity, see original site] Left-eye view of a color stereo pair for PIA11812 [figure removed for brevity, see original site] Right-eye view of a color stereo pair for PIA11812 NASA's Mars Exploration Rover Opportunity used its navigation camera to take the images combined into this stereo, full-circle view of the rover's surroundings during the 1,803rd and 1,804th Martian days, or sols, of Opportunity's surface mission (Feb. 18 and 19, 2009). South is at the center; north at both ends. This view combines images from the left-eye and right-eye sides of the navigation camera. It appears three-dimensional when viewed through red-blue glasses with the red lens on the left. The rover had driven 55 meters on Sol 1803 before beginning to take the frames in this view. Tracks from that drive recede northward. For scale, the distance between the parallel wheel tracks is about 1 meter (about 40 inches). The terrain in this portion of Mars' Meridiani Planum region includes dark-toned sand ripples and lighter-toned bedrock. This view is presented as a cylindrical-perspective projection with geometric seam correction.

  2. Sol-gel derived ceramic electrolyte films on porous substrates

    Energy Technology Data Exchange (ETDEWEB)

    Kueper, T.W.

    1992-05-01

    A process for the deposition of sol-gel derived thin films on porous substrates has been developed; such films should be useful for solid oxide fuel cells and related applications. Yttria-stabilized zirconia films have been formed from metal alkoxide starting solutions. Dense films have been deposited on metal substrates and ceramic substrates, both dense and porous, through dip-coating and spin-coating techniques, followed by a heat treatment in air. X-ray diffraction has been used to determine the crystalline phases formed and the extent of reactions with various substrates which may be encountered in gas/gas devices. Surface coatings have been successfully applied to porous substrates through the control of substrate pore size and deposition parameters. Wetting of the substrate pores by the coating solution is discussed, and conditions are defined for which films can be deposited over the pores without filling the interiors of the pores. Shrinkage cracking was encountered in films thicker than a critical value, which depended on the sol-gel process parameters and on the substrate characteristics. Local discontinuities were also observed in films which were thinner than a critical value which depended on the substrate pore size. A theoretical discussion of cracking mechanisms is presented for both types of cracking, and the conditions necessary for successful thin formation are defined. The applicability of these film gas/gas devices is discussed.

  3. Nanostructured energetic materials derived from sol-gel chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Simpson, R L; Tillotson, T M; Hrubesh, L W; Gash, A E

    2000-03-15

    Initiation and detonation properties are dramatically affected by an energetic material's microstructural properties. Sol-gel chemistry allows intimacy of mixing to be controlled and dramatically improved over existing methodologies. One material goal is to create very high power energetic materials which also have high energy densities. Using sol-gel chemistry we have made a nanostructured composite energetic material. Here a solid skeleton of fuel, based on resorcinol-formaldehyde, has nanocrystalline ammonium perchlorate, the oxidizer, trapped within its pores. At optimum stoichiometry it has approximately the energy density of HMX. Transmission electron microscopy indicated no ammonium perchlorate crystallites larger than 20 nm while near-edge soft x-ray absorption microscopy showed that nitrogen was uniformly distributed, at least on the scale of less than 80 nm. Small-angle neutron scattering studies were conducted on the material. Those results were consistent with historical ones for this class of nanostructured materials. The average skeletal primary particle size was on the order of 2.7 nm, while the nanocomposite showed the growth of small 1 nm size crystals of ammonium perchlorate with some clustering to form particles greater than 10 nm.

  4. Aero-sol-gel Reactor for Nano-powder Synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Beaucage, G.; Hyeon-Lee, J.; Kohls, D.J. [University of Cincinnati, Department of Materials Science and Engineering (United States); Pratsinis, S.E. [University of Cincinnati, Department of Chemical Engineering (United States)

    1999-09-15

    This paper discusses a new approach to the synthesis of nano-structured oxides where sol-gel reactions are carried out in aerosol droplets. This aero-sol-gel (ASG) reactor allows for manipulation of the structure, chemical composition and surface area of silica powders through variation of process parameters. ASG powders differ in nanostructure from other continuous process powders such as pyrolytic and solution-route powders. ASG powders contain mesopores (>2-nm) and micropores (<2-nm), the mesopores being responsible for high surface areas measured by nitrogen adsorption using BET theory. Primary particles of close to molecular scale are believed to lead to exceedingly large specific surface areas on the order of 600-m{sup 2}/g. These primary particles aggregate into nanometer scale mass-fractal aggregates that cluster in micron scale agglomerates. Under controlled reaction conditions the powder structure is reproducible as measured by small-angle X-ray scattering, SAXS, analysis. The ASG reactor displays transport effects similar to those previously seen in laminar flame reactors as evidenced by the effect of reactor geometry and reactant concentration on product structure.

  5. Investigation of SOL plasma interaction with graphite PFC

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Sun-Taek, E-mail: limgun2@snu.ac.kr; Kim, Hyun-Su; Jin, Younggil; Lee, Jin Young; Song, Jae-Min; Kim, Gon-Ho, E-mail: ghkim@snu.ac.kr

    2015-08-15

    Morphological changes of graphite plasma facing component (PFC) were investigated with various ion irradiation conditions which may change the sputtering yield and the scrape-off layer (SOL) plasma property. The experiments were carried out by using electron cyclotron resonance deuterium plasma with the conditions of electron density range of 2.5–3.5 × 10{sup 11} cm{sup −3}, electron temperature range of 3.3–4.1 eV, and ion energy range of 17–100 eV. The graphite morphology was changed from plane to conical tip with increasing ion energy and dose. In addition, morphological changes increase the sputtering yield due to the increase of local angle of ion incidence. The inflow of hydrocarbon causes the increase of electron density and the decrease of electron temperature due to its higher dissociation and ionization rates than those of deuterium. This result suggests that the morphological changes of graphite should be considered in the SOL plasma interaction with graphite PFC.

  6. Development of sol-gel formulations for slow release of phermones

    Science.gov (United States)

    A new type of dispenser for slow-release of semiochemicals and sex pheromones was developed based on sol-gel polymers that can be useful in monitoring, mass trapping, and mating disruption in integrated pest management (IPM). Sol-gel matrices exhibit glass characteristics and allow control of the de...

  7. Bactericidal micron-thin sol-gel films prevent pin tract and periprosthetic infection.

    Science.gov (United States)

    Qu, Haibo; Knabe, Christine; Burke, Megan; Radin, Shula; Garino, Jonathan; Schaer, Thomas; Ducheyne, Paul

    2014-08-01

    Orthopedic injuries constitute the majority of wounds sustained by U.S. soldiers in recent conflicts. The risk of infection is considerable with fracture fixation devices. In this pilot study, we examined the use of unique bactericidal micron-thin sol-gel films on fracture fixation devices and their ability to prevent and eradicate infections. External fixation was studied with micron-thin sol-gel coated percutaneous pins releasing triclosan and inserted medially into rabbit tibiae. A total of 11 rabbits received percutaneous pins that were either uncoated or sol-gel/triclosan coated. Internal fracture fixation was also studied using sol-gel coated intramedullary (IM) nails releasing vancomycin in the intramedullary tibiae. Six sheep received IM nails that were coated with a sol-gel film that either contained vancomycin or did not contain vancomycin. All animals were challenged with Staphylococcus aureus around the implant. Animals were euthanized at 1 month postoperative. Rabbits receiving triclosan/sol-gel coated percutaneous pins did not show signs of infection. Uncoated percutaneous pins had a significantly higher infection rate. In the sheep study, there were no radiographic signs of osteomyelitis with vancomycin/sol-gel coated IM nails, in contrast to the observations in the control cohort. Hence, the nanostructured sol-gel controlled release technology offers the promise of a reliable and continuous delivery system of bactericidals from orthopedic devices to prevent and treat infection.

  8. Sol-gel microextraction phases for sample preconcentration in chromatographic analysis.

    Science.gov (United States)

    Segro, Scott S; Tran, Minh Phuong; Kesani, Sheshanka; Alhendal, Abdullah; Turner, Erica B

    2010-10-01

    Sol-gel technology provides a simple and reliable method for solid-phase microextraction (SPME) fiber preparation through in situ creation of surface-bonded organic-inorganic hybrid coatings characterized by enhanced thermal stability and solvent-resistance properties that are important for the coupling of SPME with GC and HPLC, respectively. The sol-gel coating technology has led to the development of an extensive array of sol-gel sorbent coatings for SPME. In this article, sol-gel microextraction coatings are reviewed, with particular attention on their synthesis, characterization, and applications in conjunction with GC and HPLC analyses. In addition, the development of sol-gel-coated stir bars, their inherent advantages, and applications are discussed. Next, the development and applications of sol-gel capillary microextraction (CME) in hyphenation with GC and HPLC is extensively reviewed. The newly emerging germania- and titania-based sol-gel microextraction phases look promising, especially in terms of pH and hot solvent stability. Finally, sol-gel monolithic beds for CME are reviewed. Such monolithic beds are in a position to greatly improve the extracting capabilities and enhanced sensitivity in CME.

  9. Labourer: Globalement plus néfaste sur la vie du sol que les pesticides

    DEFF Research Database (Denmark)

    Hupin, Frédérique; Petersen, Søren O.; Krogh, Paul Henning

    2017-01-01

    Quels sont les impacts de l’application de produits phytosanitaires sur les populations de vers de terre et des autres organismes du sol ? Ces impacts sont-ils simples et directs ? Ou sont-ils influencés par le travail du sol et la fertilisation ? Des recherches menées à l’université d’Aarhus au ...

  10. Radiation hardening in sol-gel derived Er{sup 3+}-doped silica glasses

    Energy Technology Data Exchange (ETDEWEB)

    Hari Babu, B., E-mail: hariphy2012@gmail.com, E-mail: matthieu.lancry@u-psud.fr; León Pichel, Mónica [Laboratoire des Solides Irradiés, UMR CEA-CNRS 7642, Ecole Polytechnique, Université Paris Saclay, 91128 Palaiseau (France); Institut de Chimie Moléculaire et des Matériaux d' Orsay, UMR CNRS-UPSud 8182, Université Paris Sud, 91405 Orsay (France); Ollier, Nadège [Laboratoire des Solides Irradiés, UMR CEA-CNRS 7642, Ecole Polytechnique, Université Paris Saclay, 91128 Palaiseau (France); El Hamzaoui, Hicham; Bigot, Laurent; Savelii, Inna; Bouazaoui, Mohamed [Laboratoire PhLAM (UMR CNRS 8523), IRCICA (USR CNRS 3380), CERLA - FR CNRS 2416, Université Lille 1, Villeneuve d' Ascq Cedex F-59655 (France); Poumellec, Bertrand; Lancry, Matthieu, E-mail: hariphy2012@gmail.com, E-mail: matthieu.lancry@u-psud.fr [Institut de Chimie Moléculaire et des Matériaux d' Orsay, UMR CNRS-UPSud 8182, Université Paris Sud, 91405 Orsay (France); Ibarra, Angel [National Fusion Laboratory, CIEMAT, Avda Complutense 40, 28040 Madrid (Spain)

    2015-09-28

    The aim of the present paper is to report the effect of radiation on the Er{sup 3+}-doped sol-gel silica glasses. A possible application of these sol-gel glasses could be their use in harsh radiation environments. The sol-gel glasses are fabricated by densification of erbium salt-soaked nanoporous silica xerogels through polymeric sol-gel technique. The radiation-induced attenuation of Er{sup 3+}-doped sol-gel silica is found to increase with erbium content. Electron paramagnetic resonance studies reveal the presence of E′{sub δ} point defects. This happens in the sol-gel aluminum-silica glass after an exposure to γ-rays (kGy) and in sol-gel silica glass after an exposure to electrons (MGy). The concentration levels of these point defects are much lower in γ-ray irradiated sol-gel silica glasses. When the samples are co-doped with Al, the exposure to γ-ray radiation causes a possible reduction of the erbium valence from Er{sup 3+} to Er{sup 2+} ions. This process occurs in association with the formation of aluminum oxygen hole centers and different intrinsic point defects.

  11. Synthesis and characterization of polymer-protected rhodium and palladium sols in mixed media.

    Science.gov (United States)

    Jaine, Jacob E; Mucalo, Michael R

    2012-06-01

    A series of polymer-protected rhodium and palladium sols were generated in mixed (organic/aqueous) dispersion media. Protecting polymers used were PAA, PVP, PVA and an oligosaccharide-based protecting agent, arabinogalactan. This is the first systematic study of colloids generated in mixed solvent dispersion media with these protecting agents. The sols were characterized by TEM, UV/Vis spectrophotometry and Photon Correlation Spectroscopy (PCS). In general, the macroscopic stability of the sols depended on the protecting agent/organic cosolvent combination used, with a nonlinear dependence on cosolvent concentration. Observed sol stabilities correlated well with pre-existing hydrodynamic data for the protective polymers, e.g. radius of gyration data. Average particle size and polydispersity of all sols examined decreased as cosolvent concentration increased, with actual cosolvent concentration, protecting agent and reducing agent used influencing the extent of decrease. Sol particle sizes ranged from 0.8 nm to 6.0 nm with sol turbidities decreasing in parallel with the particle sizes. Hydrodynamic sizes (from PCS) tended to reflect the sols' macroscopic stabilities. FTIR studies using adsorbed CO as a spectroscopic surface probe indicated decreases in the ν(CO)(ads) stretching frequency with an increase in cosolvent concentration due to competitive adsorption of CO with the cosolvent molecules on the metal colloid surfaces. Copyright © 2012 Elsevier Inc. All rights reserved.

  12. Luminescent Thin Film of Doped Terbium Complex Obtained by Sol-Gel Method

    Institute of Scientific and Technical Information of China (English)

    刘丰祎; 符连社; 王俊; 李焕荣; 张洪杰

    2003-01-01

    The transparent luminescent thin films of doped terbium complex were obtained by sol-gel method. The result indicates that rare earth carboxylates with poor solubility can be homogeneously doped into sol matrix in situ. The fluorescence spectra show that the thin film material emits the characteristic narrow band emission of Tb3+ under the UV excitation.

  13. Rheological properties of boehmite sols during ageing at room temperature (30 ± 1°C) under closed condition

    Indian Academy of Sciences (India)

    M K Naskar; M Chatterjee; D Ganguli

    2002-04-01

    Boehmite sols were obtained by peptizing boehmite precipitates with glacial acetic acid. The sols were aged at room temperature (30 ± 1°C) under closed condition. Rheological properties of the sols were studied at different ageing times. The sol characteristics were interpreted by measuring their viscosity, areas of hysteresis of the flow curves and yield stress (y). Viscosity and the area of hysteresis of the flow curves increased with increasing ageing time of the sols. A sharp change of yield stress was observed during the ageing period from 15 to 36 days. The change in viscous to elastic nature and the appearance of gel point of the sol was observed by studying their oscillatory flow behaviour, i.e. by measuring loss modulus (''), elastic modulus ('), and loss tangent (tan ) of the sols. Gel point of boehmite sol was found at 36 days of ageing under closed condition at room temperature (30 ± 1°C).

  14. Fabrication of advanced electrochemical energy materials using sol-gel processing techniques

    Science.gov (United States)

    Chu, C. T.; Chu, Jay; Zheng, Haixing

    1995-01-01

    Advanced materials play an important role in electrochemical energy devices such as batteries, fuel cells, and electrochemical capacitors. They are being used as both electrodes and electrolytes. Sol-gel processing is a versatile solution technique used in fabrication of ceramic materials with tailored stoichiometry, microstructure, and properties. The application of sol-gel processing in the fabrication of advanced electrochemical energy materials will be presented. The potentials of sol-gel derived materials for electrochemical energy applications will be discussed along with some examples of successful applications. Sol-gel derived metal oxide electrode materials such as V2O5 cathodes have been demonstrated in solid-slate thin film batteries; solid electrolytes materials such as beta-alumina for advanced secondary batteries had been prepared by the sol-gel technique long time ago; and high surface area transition metal compounds for capacitive energy storage applications can also be synthesized with this method.

  15. Reconstruction of active regular motion in amoeba extract: dynamic cooperation between sol and gel states.

    Science.gov (United States)

    Nishigami, Yukinori; Ichikawa, Masatoshi; Kazama, Toshiya; Kobayashi, Ryo; Shimmen, Teruo; Yoshikawa, Kenichi; Sonobe, Seiji

    2013-01-01

    Amoeboid locomotion is one of the typical modes of biological cell migration. Cytoplasmic sol-gel conversion of an actomyosin system is thought to play an important role in locomotion. However, the mechanisms underlying sol-gel conversion, including trigger, signal, and regulating factors, remain unclear. We developed a novel model system in which an actomyosin fraction moves like an amoeba in a cytoplasmic extract. Rheological study of this model system revealed that the actomyosin fraction exhibits shear banding: the sol-gel state of actomyosin can be regulated by shear rate or mechanical force. Furthermore, study of the living cell indicated that the shear-banding property also causes sol-gel conversion with the same order of magnitude as that of shear rate. Our results suggest that the inherent sol-gel transition property plays an essential role in the self-regulation of autonomous translational motion in amoeba.

  16. Reconstruction of active regular motion in amoeba extract: dynamic cooperation between sol and gel states.

    Directory of Open Access Journals (Sweden)

    Yukinori Nishigami

    Full Text Available Amoeboid locomotion is one of the typical modes of biological cell migration. Cytoplasmic sol-gel conversion of an actomyosin system is thought to play an important role in locomotion. However, the mechanisms underlying sol-gel conversion, including trigger, signal, and regulating factors, remain unclear. We developed a novel model system in which an actomyosin fraction moves like an amoeba in a cytoplasmic extract. Rheological study of this model system revealed that the actomyosin fraction exhibits shear banding: the sol-gel state of actomyosin can be regulated by shear rate or mechanical force. Furthermore, study of the living cell indicated that the shear-banding property also causes sol-gel conversion with the same order of magnitude as that of shear rate. Our results suggest that the inherent sol-gel transition property plays an essential role in the self-regulation of autonomous translational motion in amoeba.

  17. Characterization of Rod-like High-purity Fluorapatite Nanopowders Obtained by Sol-gel Method

    Directory of Open Access Journals (Sweden)

    Nasrin Sasani

    2013-12-01

    Full Text Available high purity fluorapatite (FA with rod-like and spherical-like morphology was synthesized via sol-gel method. Chemical characterization of FA powders was done by XRD and FTIR analyses. Crystallite samples were calculated using Scherer method. Morphology of FA powders was investigated with TEM and SEM images. The results revealed that increasing the time of hydrolysis of phosphate sols significantly decreased the gelation time of FA sols. Also, mixing temperature of P and Ca sols affects the gelation time of samples and increasing pH decreases the gelation time of FA sols. Morphological and chemical characterization of samples showed that the FA powders have high purity and rod-like and spherical-like morphology.

  18. Synthesis of organic-inorganic hybrid sols using trifunctional organoalkoxysilanes for dispersion agents.

    Science.gov (United States)

    Park, Hoyyul; Kang, Dongjun; Ahn, Myeongsang; Lee, Hyeonhwa

    2012-02-01

    We investigated the properties of synthetically produced organic-inorganic hybrid coatings by a sol-gel process. The properties of organic-inorganic hybrid materials arise from the synergism between the properties of the individual components. One of the typical way to synthesize the organic-inorganic hybrid materials is to use silica and silanes. A colloidal silica sol was used as an inorganic material. Methyltrimethoxysilane and phenyltrimethoxysilane were used as the trifunctional organoalkoxysilanes. Hybrid sols of colloidal silica and silanes were synthesized as a function of reaction time and methyltrimethoxysilane/phenyltrimethoxysilane ratio by a sol-gel process. Physical properties of sol solutions such as stability, viscosity, and transmittance were investigated. The surface roughness and surface free energy of the coatings were also measured.

  19. Preparation and stabilization of aluminium trifluoroacetate fluoride sols for optical coatings.

    Science.gov (United States)

    Fritz, C; Scholz, G; Feist, M; Kemnitz, E

    2012-10-07

    For the first time, aluminium fluorides in liquid phase are available for optical applications. By modifying the conditions of the fluorolytic sol-gel synthesis of aluminium fluorides transparent sols with low viscosities were obtained. These sols consist mainly of small oligomeric or cluster units of aluminium fluoride which are not measurable by DLS, WAXS, SAXS and show unusual narrow signals in solid state NMR. Isolated particles with diameters up to five nanometers can be identified by TEM measurements and allow the use of their sols in optical and anti reflecting coatings. The sol particles were modified by trifluoroacetic acid to prevent agglomeration, and as a result, the obtained xerogels can be re-dispersed transparently in organic solvents.

  20. 76 FR 41816 - Notice of Intent To Prepare an Environmental Impact Statement for the Proposed Ocotillo Sol Solar...

    Science.gov (United States)

    2011-07-15

    ... Ocotillo Sol Solar Project, Imperial County, CA; Possible Land Use Plan Amendment; and Notice of... & Electric's (SDG&E) right-of-way (ROW) authorization request for the Ocotillo Sol Solar Energy Facility... related to the Ocotillo Sol Solar Project by any of the following methods: Mail: Noel Ludwig,...

  1. Structure and growth of polymeric niobia-silica mixed-oxide sols for microporous molecular sieving membranes: a SAXS study

    NARCIS (Netherlands)

    Boffa, V.; Castricum, H.L.; Garcia, R.; Schmuhl, R.; Petukhov, A.V.; Blank, D.H.A.; ten Elshof, J.E.

    2009-01-01

    Branched polymeric niobia-silica (NS) mixed-oxide sols with a Nb:Si molar ratio between 0.33 and 0.8 were made by acid-catalyzed sol-gel synthesis and characterized using small-angle X-ray scattering (SAXS) and dynamic light scattering (DLS). The growth rate of NS sols after addition of a niobium al

  2. Influence of precursor ratios on the properties of cotton coated with a sol-gel flame retardant

    CSIR Research Space (South Africa)

    Chapple, Stephen A

    2006-11-01

    Full Text Available and strength), coatings were applied to cotton fabrics using different ratios of sol-gel precursors. The results showed that the ratio of sol-gel precursors influenced fabric stiffness and strength but not flammability. The distribution of the sol-gel flame...

  3. A utilização de materiais obtidos pelo processo de sol-gel na construção de biossensores The utilization of materials obtained by the sol-gel process in biosensors construction

    Directory of Open Access Journals (Sweden)

    Antonio A. S. Alfaya

    2002-09-01

    Full Text Available The use of sol-gel materials to develop new biosensors has received great attention due to its characteristics and versatility of sol-gel process. An overview is presented of the state-of-the-art of electrochemical biosensors employing sol-gel materials. Low-temperature, porous sol-gel ceramics represent a new class for the immobilization of biomolecules. The rational design of sol-gel sensing materials, based on the judicious choice of the starting alkoxide, encapsulated reagents, and preparation conditions, allows tailoring of material properties in a wide range, and offers great potential for the development of electrochemical biosensors.

  4. Conductivity Probe Inserted in Martian Soil, Sol 46

    Science.gov (United States)

    2008-01-01

    This image taken by the Surface Stereo Imager on NASA's Phoenix Mars Lander shows the lander's Thermal and Electrical Conductivity Probe (TECP), at the end of the Robotic Arm, on the 46th Martian day, or sol, of the mission (July 11, 2008). The TECP is inserted at a site called Vestri, which was monitored several times over the course of the mission. The probe's measurements at this site yielded evidence that water was exchanged, daily and seasonally, between the soil and atmosphere. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  5. Polymer sol-gel composite inverse opal structures.

    Science.gov (United States)

    Zhang, Xiaoran; Blanchard, G J

    2015-03-25

    We report on the formation of composite inverse opal structures where the matrix used to form the inverse opal contains both silica, formed using sol-gel chemistry, and poly(ethylene glycol), PEG. We find that the morphology of the inverse opal structure depends on both the amount of PEG incorporated into the matrix and its molecular weight. The extent of organization in the inverse opal structure, which is characterized by scanning electron microscopy and optical reflectance data, is mediated by the chemical bonding interactions between the silica and PEG constituents in the hybrid matrix. Both polymer chain terminus Si-O-C bonding and hydrogen bonding between the polymer backbone oxygens and silanol functionalities can contribute, with the polymer mediating the extent to which Si-O-Si bonds can form within the silica regions of the matrix due to hydrogen-bonding interactions.

  6. Fullerenol-containing Materials Derived by Sol-gel Processing

    Institute of Scientific and Technical Information of China (English)

    Haiping XIA; Zhaoyang JIANG; Jianli ZHANG; Jinhao WANG; Yuepin ZHANG; Qiuhua NIE

    2004-01-01

    Water soluble fullerenols were synthesized and incorporated in SiO2, SiO2-TiO2, GPTMS-SiO2, GPTMS-ATPS inorganic and organic-inorganic materials by sol-gel processes. The maximum concentrations of C60(OH)n and C7o(OH)n in the obtained SiO2 gels were estimated to be about 0.6% and 1.5% in weight, respectively. The characteristics of the UV/visible spectra of fullerenols in H2O and various gels were measured and compared. The thermal stability of fullerenols in gels was investigated with differential thermal analysis (DTA). The results indicate that the absorption features of fullerenols in solid gels are similar to those in H2O and the fullerenols in SiO2 are stable at 400℃. The optical limiting effect of the fullerenols was investigated preliminarily.

  7. Novel Synthesis of Sol-gel Derived Nanosized Mullite Powder

    Institute of Scientific and Technical Information of China (English)

    LIANG Long; LI Jian-bao; LIN Hong; GUO Gang-feng; HE Ming-sheng

    2006-01-01

    Using hydrous aluminum chloride (AlCl3 6H2O) and silicon ethoxide (Si (OC2H5)4) as raw materials, a kind of nano-sized mullite powder was synthesized with the sol-gel process at the medium calcination temperature. The microstructures of the alumina-silica binary aerogel and calcined nano-sized materials were investigated by means of thermogravimetry-differential thermal analysis (TG-DTA), scanning electron microscopy (SEM) and X-ray diffractometer (XRD). The results show that the mullitization of Al2O3-SiO2 in gel starts from about 1 000 ℃ and its formation of mullite takes place in the range of 1 100 ℃-1 250 ℃. The size of the nano-sized mullite powder calcined at 1 250 ℃ is measured to be about 30 nm.

  8. Manufacture of Regularly Shaped Sol-Gel Pellets

    Science.gov (United States)

    Leventis, Nicholas; Johnston, James C.; Kinder, James D.

    2006-01-01

    An extrusion batch process for manufacturing regularly shaped sol-gel pellets has been devised as an improved alternative to a spray process that yields irregularly shaped pellets. The aspect ratio of regularly shaped pellets can be controlled more easily, while regularly shaped pellets pack more efficiently. In the extrusion process, a wet gel is pushed out of a mold and chopped repetitively into short, cylindrical pieces as it emerges from the mold. The pieces are collected and can be either (1) dried at ambient pressure to xerogel, (2) solvent exchanged and dried under ambient pressure to ambigels, or (3) supercritically dried to aerogel. Advantageously, the extruded pellets can be dropped directly in a cross-linking bath, where they develop a conformal polymer coating around the skeletal framework of the wet gel via reaction with the cross linker. These pellets can be dried to mechanically robust X-Aerogel.

  9. Moment scaling at the sol-gel transition

    Energy Technology Data Exchange (ETDEWEB)

    Botet, R. [Paris-11 Univ., 91 - Orsay (France). Lab. de Physique des Solides; Ploszajczak, M. [Grand Accelerateur National d`Ions Lourds, 14 - Caen (France)

    1998-05-06

    Two standard models of sol-gel transition are revisited here from the point of view of their fluctuations in various moments of both the mass-distribution and the gel-mass. Bond-percolation model is an at-equilibrium system and undergoes a static second-order phase transition, while Monte-Carlo Smoluchowski model is an off-equilibrium one and shows a dynamical critical phenomenon. It is shown that the macroscopic quantities can be splitted into the three classes with different scaling properties of their fluctuations, depending on whether they correspond to: (i) non-critical quantities, (ii) critical quantities or to (iii) an order parameter. (author) 15 refs.

  10. True Color of Mars - Pathfinder Sol 39 Sunrise

    Science.gov (United States)

    1999-01-01

    Sunrise, sol 39. This true color, pre-sunrise image (approximately 0530LST) is composed of six images extending 30 o in azimuth and 45 o in elevation and shows the brownish gray predawn sky. A description of the techniques used to generate this color image from IMP data can be found in Maki et al., 1999. Note: a calibrated output device is required accurately reproduce the correct colors.Mars Pathfinder is the second in NASA's Discovery program of low-cost spacecraft with highly focused science goals. The Jet Propulsion Laboratory, Pasadena, CA, developed and manages the Mars Pathfinder mission for NASA's Office of Space Science, Washington, D.C. JPL is an operating division of the California Institute of Technology (Caltech). The IMP was developed by the University of Arizona Lunar and Planetary Laboratory under contract to JPL. Peter Smith is the Principal investigator.

  11. Photochromic gratings in sol gel films containing diazo sulfonamide chromophore

    Science.gov (United States)

    Kucharski, Stanisław; Janik, Ryszard

    2005-09-01

    The photochromic sol-gel hybrid materials were prepared by incorporation of an azo chromophore containing sulfonamide fragment into polysiloxane cross-linked network. The materials were used to form transparent films on glass by spin-coating and/or casting. The reversible change of refraction index of the films on illumination with white light was observed by ellipsometry. The experiments with two beam coupling (TBC) and four wave mixing (4 WM) arrangement with green or blue laser beams as writing beams showed formation of a diffraction grating. The diffraction efficiency of the first order was 0.025-0.038 which yielded refraction index modulation in the range of up to 0.0066.

  12. Multifunctional bioinspired sol-gel coatings for architectural glasses

    Energy Technology Data Exchange (ETDEWEB)

    Cannavale, Alessandro; Fiorito, Francesco; Tortorici, Giovanni [Politecnico di Bari, Dipartimento di Architettura e Urbanistica, Via E. Orabona, 4, 70126, Bari (Italy); Manca, Michele; Cingolani, Roberto; Gigli, Giuseppe [Center for Biomolecular Nanotechnologies (CBN) of the Italian Institute of Technology (IIT), Via Barsanti 1, 73010, Arnesano (LECCE) (Italy)

    2010-05-15

    Although several multinational companies have recently released products incorporating bioinspired functional coatings, their practical integration in building envelopes is still an open issue. High production costs associated to the existing vacuum deposition technologies, as well as the difficulties in extending the number of functions achievable by a single coating, represent to date the main limitations to their diffusion on a large scale. This review summarizes the key topics in the field of functional coatings for architectural glasses, focusing in particular on the potential applications of sol-gel based antireflective and self-cleaning coatings, that have received a tremendous attention in the last years. It provides an overview of the recent research efforts aimed to improve their properties and to extend their range of applicability. The bioinspired principles, upon which such coatings are based, are also described and are related to the chemical and morphological properties of such surfaces. (author)

  13. Bioorganically doped sol-gel materials containing amyloglucosidase activity

    Directory of Open Access Journals (Sweden)

    Vlad-Oros Beatrice

    2006-01-01

    Full Text Available Amyloglucosidase (AMG from Aspergillus niger was encapsulated in various matrices derived from tetraethoxysilane, methyltriethoxysilane, phenyltriethoxysilane and vinyltriacetoxysilane by different methods of immobilization. The immobilized enzyme was prepared by entrapment in two steps, in one-step and entrapment/deposition, respectively. The activities of the immobilized AMG were assayed and compared with that of the native enzyme. The effects of the organosilaneprecursors and their molar ratios, the immobilization method, the inorganic support (white ceramic, red ceramic, purolite, alumina, TiO2, celite, zeolite and enzyme loading upon the immobilized enzyme activity were tested. The efficiency of the sol-gel biocomposites can be improved through combination of the fundamental immobilization techniques and selection of the precursors.

  14. Sol-Gel Glass Holographic Light-Shaping Diffusers

    Science.gov (United States)

    Yu, Kevin; Lee, Kang; Savant, Gajendra; Yin, Khin Swe (Lillian)

    2005-01-01

    Holographic glass light-shaping diffusers (GLSDs) are optical components for use in special-purpose illumination systems (see figure). When properly positioned with respect to lamps and areas to be illuminated, holographic GLSDs efficiently channel light from the lamps onto specified areas with specified distributions of illumination for example, uniform or nearly uniform irradiance can be concentrated with intensity confined to a peak a few degrees wide about normal incidence, over a circular or elliptical area. Holographic light diffusers were developed during the 1990s. The development of the present holographic GLSDs extends the prior development to incorporate sol-gel optical glass. To fabricate a holographic GLSD, one records a hologram on a sol-gel silica film formulated specially for this purpose. The hologram is a quasi-random, micro-sculpted pattern of smoothly varying changes in the index of refraction of the glass. The structures in this pattern act as an array of numerous miniature lenses that refract light passing through the GLSD, such that the transmitted light beam exhibits a precisely tailored energy distribution. In comparison with other light diffusers, holographic GLSDs function with remarkably high efficiency: they typically transmit 90 percent or more of the incident lamp light onto the designated areas. In addition, they can withstand temperatures in excess of 1,000 C. These characteristics make holographic GLSDs attractive for use in diverse lighting applications that involve high temperatures and/or requirements for high transmission efficiency for ultraviolet, visible, and near-infrared light. Examples include projectors, automobile headlights, aircraft landing lights, high-power laser illuminators, and industrial and scientific illuminators.

  15. Mayenite Synthesized Using the Citrate Sol-Gel Method

    Energy Technology Data Exchange (ETDEWEB)

    Ude, Sabina N [ORNL; Rawn, Claudia J [ORNL; Meisner, Roberta A [University of Tennessee (UTK) and Oak Ridge National Laboratory (ORNL); Kirkham, Melanie J [ORNL; Jones, Gregory L. [University of Tennessee, Knoxville (UTK); Payzant, E Andrew [ORNL

    2014-01-01

    A citrate sol-gel method has been used to synthesize mayenite (Ca12Al14O33). X-ray powder diffraction data show that the samples synthesized using the citrate sol-gel method contained CaAl2O4 and CaCO3 along with mayenite when fired ex-situ in air at 800 C but were single phase when fired at 900 C and above. Using high temperature x-ray diffraction, data collected in-situ in air at temperatures of 600 C and below showed only amorphous content; however, data collected at higher temperatures indicated the first phase to crystallize is CaCO3. High temperature x-ray diffraction data collected in 4% H2/96% N2 does not show the presence of CaCO3, and Ca12Al14O33 starts to form around 850 C. In comparison, x-ray powder diffraction data collected ex-situ on samples synthesized using traditional solid-state synthesis shows that single phase was not reached until samples were fired at 1350 C. DTA/TGA data collected either in a nitrogen environment or air on samples synthesized using the citrate gel method suggest the complete decomposition of metastable phases and the formation of mayenite at 900 C, although the phase evolution is very different depending on the environment. Brunauer-Emmett-Teller (BET) measurements showed a slightly higher surface area of 7.4 0.1 m2/g in the citrate gel synthesized samples compared to solid-state synthesized sample with a surface area of 1.61 0.02 m2/g. SEM images show a larger particle size for samples synthesized using the solid-state method compared to those synthesized using the citrate gel method.

  16. COMPARISON OF SOL-GEL SILICATE COATINGS ON Ti SUBSTRATE

    Directory of Open Access Journals (Sweden)

    DIANA HORKAVCOVÁ

    2012-12-01

    Full Text Available The objective of the submitted work was to prepare and to characterize two types of silicate coatings prepared by the sol-gel method using the dip-coating technique on a titanium substrate. Efforts have been made to use mechanical properties of bio-inert titanium and bioactive properties of a silicate layer enriched with an admixture of compounds identified below. The first group consisted of silicate coatings containing silver, brushite and monetite. The other group of silicate coatings contained calcium nitrate and triethyl phosphate. Mechanically and chemically treated titanium substrates were dipped into sols and dried and fired. Silicate coatings from the first group were also chemically treated in 10 mol.l-1 solution of sodium hydroxide. All coatings were measured to determine their adhesive and bioactive properties and furthermore the antibacterial properties were tested in the case of first group. Surfaces of the coated substrates were investigated after the firing and after the individual tests with optical and electron microscopy and X-ray microdiffraction. A tape test demonstrated excellent adhesive property of all coatings to the substrate, classified with degree 5. A static in vitro test demonstrated bioactivity of nearly all the coatings. The basic silicate coating from the first group and one type of coating from the second group were identified as inert. Antibacterial properties of silicate coatings containing silver showed to be different when tested against Escherichia coli bacteria. A complete inhibition of the growth of bacteria under our experimental conditions was observed for the coating containing silver and monetite and a partial inhibition of the growth of bacteria for coatings containing silver and silver in combination with brushite.

  17. Sol-Gel processing of silica nanoparticles and their applications.

    Science.gov (United States)

    Singh, Lok P; Bhattacharyya, Sriman K; Kumar, Rahul; Mishra, Geetika; Sharma, Usha; Singh, Garima; Ahalawat, Saurabh

    2014-11-06

    Recently, silica nanoparticles (SNPs) have drawn widespread attention due to their applications in many emerging areas because of their tailorable morphology. During the last decade, remarkable efforts have been made on the investigations for novel processing methodologies to prepare SNPs, resulting in better control of the size, shape, porosity and significant improvements in the physio-chemical properties. A number of techniques available for preparing SNPs namely, flame spray pyrolysis, chemical vapour deposition, micro-emulsion, ball milling, sol-gel etc. have resulted, a number of publications. Among these, preparation by sol-gel has been the focus of research as the synthesis is straightforward, scalable and controllable. Therefore, this review focuses on the recent progress in the field of synthesis of SNPs exhibiting ordered mesoporous structure, their distribution pattern, morphological attributes and applications. The mesoporous silica nanoparticles (MSNPs) with good dispersion, varying morphology, narrow size distribution and homogeneous porous structure have been successfully prepared using organic and inorganic templates. The soft template assisted synthesis using surfactants for obtaining desirable shapes, pores, morphology and mechanisms proposed has been reviewed. Apart from single template, double and mixed surfactants, electrolytes, polymers etc. as templates have also been intensively discussed. The influence of reaction conditions such as temperature, pH, concentration of reagents, drying techniques, solvents, precursor, aging time etc. have also been deliberated. These MSNPs are suitable for a variety of applications viz., in the drug delivery systems, high performance liquid chromatography (HPLC), biosensors, cosmetics as well as construction materials. The applications of these SNPs have also been briefly summarized. Copyright © 2014 Elsevier B.V. All rights reserved.

  18. Characterization of Ceramic Composite-Membranes Prepared by ORMOSIL Coating Sol

    Institute of Scientific and Technical Information of China (English)

    Goo-Dae Kim; Tae-Bong Kim

    2004-01-01

    Sol-gel methods offer many advantages over conventional slip-casting, including the ability to produce ceramic membranes. They are purer, more homogeneous, more reactive and contain a wider variety of compositions. We produced ormosil sol using sol-gel process under different molecular weight of polymer species [polyethylene glycol (PEG) ] in total system [Tetraethyl ortho silicate(TEOS)-polyethylene glycol (PEG)]. The properties of as-prepared ormosil sol such as,viscosity, gelation time were characterized. Also, the ceramic membrane was prepared by dip-coating with synthetic sol and its micro-structure was observed by scanning electron microscopy. The permeability and rejection efficiency of membrane for oil/water emulsion were evaluated as cross-flow apparatus. The ormosil sol coated Membrane is easily formed by steric effect of polymer and it improves flux efficiency because infiltration into porous support decreased. Its flux efficiency is elevated about 200(1/m2·h) compared with colloidal sol coated membrane at point of five minutes from starting test.

  19. Optical Characterization of Chemically Etched Nanoporous Silicon Embedded in Sol-Gel Matrix

    Directory of Open Access Journals (Sweden)

    A. S. Al Dwayyan

    2012-01-01

    Full Text Available Nanoporous (NPs silicon fabricated by chemical etching process in HF acid was first separated in tetrahydrofuran (THF solvent and then incorporated into SiO2 matrix. The matrix was prepared by sol gel process in which dimethylformamide (DMF was used as drying chemical control additive (DCCA to form crack-free dried sample. We examined the optical properties of NPs in three medium which are solvent, sol, and dried sol gel. Our observations reveal that absorption spectra of NPs silicon in THF are modified with respect to the spectra in sol gel. Significant stability in PL of NPs silicon in the sol gel is observed. Influence of matrix environment on peaks of NPs is also discussed. Surface morphology is characterized by field emission scanning electron microscopy (FESEM which shows that the NPs silicon in THF is similar to the sol gel but becomes aggregation particle to particle. Presence of Si nanoparticles in THF and sol is confirmed by Transmission electron microscopy (TEM. The NPs silicons have mono dispersive and high crystalline nature with spherical shape of around 5 nm in sizes.

  20. A silica sol-gel design strategy for nanostructured metallic materials.

    Science.gov (United States)

    Warren, Scott C; Perkins, Matthew R; Adams, Ashley M; Kamperman, Marleen; Burns, Andrew A; Arora, Hitesh; Herz, Erik; Suteewong, Teeraporn; Sai, Hiroaki; Li, Zihui; Werner, Jörg; Song, Juho; Werner-Zwanziger, Ulrike; Zwanziger, Josef W; Grätzel, Michael; DiSalvo, Francis J; Wiesner, Ulrich

    2012-03-18

    Batteries, fuel cells and solar cells, among many other high-current-density devices, could benefit from the precise meso- to macroscopic structure control afforded by the silica sol-gel process. The porous materials made by silica sol-gel chemistry are typically insulators, however, which has restricted their application. Here we present a simple, yet highly versatile silica sol-gel process built around a multifunctional sol-gel precursor that is derived from the following: amino acids, hydroxy acids or peptides; a silicon alkoxide; and a metal acetate. This approach allows a wide range of biological functionalities and metals--including noble metals--to be combined into a library of sol-gel materials with a high degree of control over composition and structure. We demonstrate that the sol-gel process based on these precursors is compatible with block-copolymer self-assembly, colloidal crystal templating and the Stöber process. As a result of the exceptionally high metal content, these materials can be thermally processed to make porous nanocomposites with metallic percolation networks that have an electrical conductivity of over 1,000 S cm(-1). This improves the electrical conductivity of porous silica sol-gel nanocomposites by three orders of magnitude over existing approaches, opening applications to high-current-density devices.

  1. Formulation and evaluation of antimicrobial activity of Morus alba sol-gel against periodontal pathogens

    Directory of Open Access Journals (Sweden)

    Shilpa Gunjal

    2015-01-01

    Full Text Available Background: Periodontitis has a multifactorial etiology, with primary etiologic agents being pathogenic bacteria that reside in the subgingival area. Recent advances in the field of alternative medicine introduced various herbal products for the treatment of periodontitis. Aim: To assess and compare the antimicrobial activity of Morus alba sol-gel with chlorhexidine sol-gel against ATCC standard strains of Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, and Tannerella forsythia. Materials and Methods: Crude extract of Morus alba leaves was prepared by Soxhlet method by using ethanol as a solvent. Phytochemical screening of the crude extract of M. alba was performed to check the various chemical constituents. M. alba sol-gel and chlorhexidine sol-gel were formulated using Pluronic f127 and Pluronic f108 and compared for their antimicrobial activity. The minimum inhibitory concentration of both the gels was performed using agar well diffusion technique. Results: The minimum inhibitory concentration of M. alba sol-gel and chlorhexidine sol-gel against A. actinomycetemcomitans is 19 and 17 mm, T. forsythia is 12 and 21 mm, and P. gingivalis is 16 and 18 mm, respectively. Conclusion: Both M. alba and chlorhexidine sol-gel exhibited potent antimicrobial activity against periodontal pathogens.

  2. Core-SOL modelling of neon seeded JET discharges with the ITER-like wall

    Energy Technology Data Exchange (ETDEWEB)

    Telesca, G. [Department of Applied Physics, Ghent University (Belgium); EUROfusion Consortium, JET, Culham Science Centre, Abingdon (United Kingdom); Ivanova-Stanik, I.; Zagoerski, R.; Czarnecka, A. [Institute of Plasma Physics and Laser Microfusion, Warsaw (Poland); EUROfusion Consortium, JET, Culham Science Centre, Abingdon (United Kingdom); Brezinsek, S.; Huber, A.; Wiesen, S. [Forschungszentrum Juelich GmbH, Institut fuer Klima- und Energieforschung-Plasmaphysik, Juelich (Germany); EUROfusion Consortium, JET, Culham Science Centre, Abingdon (United Kingdom); Drewelow, P. [Max-Planck-Institut fuer Plasmaphysik, Greifswald (Germany); EUROfusion Consortium, JET, Culham Science Centre, Abingdon (United Kingdom); Giroud, C. [CCFE Culham, Abingdon (United Kingdom); EUROfusion Consortium, JET, Culham Science Centre, Abingdon (United Kingdom); Collaboration: JET EFDA contributors

    2016-08-15

    Five ELMy H-mode Ne seeded JET pulses have been simulated with the self-consistent core-SOL model COREDIV. In this five pulse series only the Ne seeding rate was changed shot by shot, allowing a thorough study of the effect of Ne seeding on the total radiated power and of its distribution between core and SOL tobe made. The increase in the simulations of the Ne seeding rate level above that achieved in experiments shows saturation of the total radiated power at a relatively low radiated-heating power ratio (f{sub rad} = 0.60) and a further increase of the ratio of SOL to core radiation, in agreement with the reduction of W release at high Ne seeding level. In spite of the uncertainties caused by the simplified SOL model of COREDIV (neutral model, absence of ELMs and slab model for the SOL), the increase of the perpendicular transport in the SOL with increasing Ne seeding rate, which allows to reproduce numerically the experimental distribution core-SOL of the radiated power, appears to be of general applicability. (copyright 2016 The Authors. Contributions to Plasma Physics published by Wiley-VCH Verlag GmbH and Co. KGaA Weinheim. This)

  3. Synthesis of polymeric fluorinated sol-gel precursor for fabrication of superhydrophobic coating

    Science.gov (United States)

    Li, Qianqian; Yan, Yuheng; Yu, Miao; Song, Botao; Shi, Suqing; Gong, Yongkuan

    2016-03-01

    A fluorinated polymeric sol-gel precursor (PFT) is synthesized by copolymerization of 2,3,4,5,5,5-hexafluoro-2,4-bis(trifluorinated methyl)pentyl methacrylate (FMA) and 3-methacryloxypropyltrimethoxysilane (TSMA) to replace the expensive long chain fluorinated alkylsilanes. The fluorinated silica sol is prepared by introducing PFT as co-precursor of tetraethyl orthosilicate (TEOS) in the sol-gel process with ammonium hydroxide as catalyst, which is then used to fabricate superhydrophobic coating on glass substrate through a simple dip-coating method. The effects of PFT concentrations on the chemical structure of the formed fluorinated silica, the surface chemical composition, surface morphology, wetting and self-cleaning properties of the resultant fluorinated silica coatings were studied by using X-ray powder diffraction (XRD), Fourier transform infrared spectrometer (FTIR), X-ray photoelectron spectrophotometer (XPS), scanning electron microscopy (SEM) and water contact angle measurements (WCA). The results show that the fluorinated silica sols are successfully obtained. The size and size distribution of the fluorinated silica particles are found greatly dependent on the concentration of PFT, which play a crucial role in the surface morphology of the corresponding fluorinated silica coatings. The suitable PFT concentration added in the sol-gel stage, i.e. for F-sol-1 and F-sol-2, is helpful to achieve both the low surface energy and multi-scaled microstructures, leading to the formation of the superhydrophobic coatings with bio-mimicking self-cleaning property similar to lotus leaves.

  4. 紫杉醇联合替尼泊苷对胃癌BGC-823细胞增殖和凋亡的影响%Effects of taxol and VM-26 on proliferation and apoptosis of gastric cancer cell line BGC-823

    Institute of Scientific and Technical Information of China (English)

    罗执芬; 周云; 刘明月

    2009-01-01

    目的:探讨紫杉醇(Taxol)和替尼泊苷(VM-26)联合应用对胃癌BGC-823细胞的体外抑制和诱导细胞凋亡的作用.方法:采用MTT法测定Taxol单药(0.75、1.50、3.00、6.00、12.00 mg/L),VM-26单药(1.25、2.50、5.00、10.00、20.00mg/L)及联合用药(0.75/1.25,1.5/2.50,3.00/5.00,6.00/10.00,12.00/20.00 mg/L)对BGC-823细胞的生长抑制率,应用流式细胞仪测定0.75 mg/L Taxol、1.25 mg/L VM-26单药及其联合用药作用0,12,24,48 h各时间点的细胞周期和凋亡率.结果:Taxol和VM-26单药及联合用药对BGC-823细胞的生长抑制率随药物的质量浓度的增加而增加.联合用药指数(CI)为1.43.经1.25 mg/L的VM-26和0.75 mg/L Taxol单药及联合用药均可诱导胃癌BGC-823细胞的凋亡,Taxol单药处理后24 h,使G2/M细胞显著增多,S期细胞显著减少;VM-26单药处理后48 h,G1/G0、S期细胞减少,G2/M期细胞显著增加.结论:Taxol与VM-26单药均可抑制胃癌BGC-823细胞的生长,诱导细胞凋亡,联合用药对胃癌BGC-823细胞的生长抑制有拮抗作用.

  5. Crystal structure of Sol I 2: a major allergen from fire ant venom.

    Science.gov (United States)

    Borer, Aline S; Wassmann, Paul; Schmidt, Margit; Hoffman, Donald R; Zhou, Jing-Jiang; Wright, Christine; Schirmer, Tilman; Marković-Housley, Zora

    2012-01-27

    Sol i 2 is a potent allergen from the venom of red imported fire ant, which contains allergens Sol i 1, Sol i 2, Sol i 3, and Sol i 4 that are known to be powerful triggers of anaphylaxis. Sol i 2 causes IgE antibody production in about one-third of individuals stung by fire ants. Baculovirus recombinant dimeric Sol i 2 was crystallized as a native and selenomethionyl-derivatized protein, and its structure has been determined by single-wavelength anomalous dispersion at 2.6 Å resolution. The overall fold of each subunit consists of five helices that enclose a central hydrophobic cavity. The structure is stabilized by three intramolecular disulfide bridges and one intermolecular disulfide bridge. The nearest structural homologue is the sequence-unrelated odorant binding protein and pheromone binding protein LUSH of the fruit fly Drosophila, which may suggest a similar biological function. To test this hypothesis, we measured the reversible binding of various pheromones, plant odorants, and other ligands to Sol i 2 by the changes in N-phenyl-1-naphthylamine fluorescence emission upon binding of ligands that compete with N-phenyl-1-naphthylamine. The highest binding affinity was observed for hydrophobic ligands such as aphid alarm pheromone (E)-β-farnesene, analogs of ant alarm pheromones, and plant volatiles decane, undecane, and β-caryophyllene. Conceivably, Sol i 2 may play a role in capturing and/or transporting small hydrophobic ligands such as pheromones, odors, fatty acids, or short-living hydrophobic primers. Molecular surface analysis, in combination with sequence alignment, can explain the serological cross-reactivity observed between some ant species.

  6. Macroporous Titania Monolith Prepared via Sol-gel Process with Polymer Foam as the Template

    Institute of Scientific and Technical Information of China (English)

    REN, Jian; DU, Zhong-Jie; ZHANG, Chen; LI, Hang-Quan

    2006-01-01

    Macroporous titania monoliths were prepared via sol-gel method using polymer foam as templates. The polymer foam polymerized via concentrated emulsion polymerization was immerged in a solution of titanium(Ⅳ) isopropoxide in 2-propanol, which underwent a sol-gel process. The organic components were subsequently removed by calcination. The effects of various parameters, including the nature of the monomer, the volume fraction of dispersed phase of the concentrated emulsion, and concentration of the sol-gel solution were investigated. The SEM micrographs of the macroporous titania monoliths thus obtained showed that the porous structure of the final material was effectively controllable.

  7. Preparation of selective surfaces of black cobalt by the sol-gel process

    Energy Technology Data Exchange (ETDEWEB)

    Barrera, E.C.; Viveros, T.G.; Morales, U. [Universidad Nacional Autonoma de Mexico, Iztapalapa (Mexico)

    1996-09-01

    Black cobalt, Co{sub 3}O{sub 4}, thin solid coatings on stainless steel and glass substrates have been prepared by the dip coating technique via the sol-gel route using a CoCl{sub 2} precursor. The coatings produced on substrates exhibit a blue to black colours as a function of the film thickness. Sols have been made from a cobalt acetate precursor 0.1 M, and for such conditions, the dip coating process gives 0.08-0.25 {mu}m thick uniform films per dipping, depending on the viscocity of the sol. (Author)

  8. Ultrasound-assisted sol-gel synthesis of ZrO2.

    Science.gov (United States)

    Guel, Marlene Lariza Andrade; Jiménez, Lourdes Díaz; Hernández, Dora Alicia Cortés

    2017-03-01

    Synthesis of tetragonal ZrO2 by both conventional sol-gel and ultrasound-assisted sol-gel methods and using a non-ionic surfactant Tween-20, was performed. A porous microstructure composed of nanometric particles was observed. Tetragonal ZrO2 was obtained using a low heat treatment temperature of powders, 500°C by both methods. A higher crystallinity and a shorter reaction time were observed when ultrasound was used in the sol-gel method due to the cavitation phenomenon.

  9. Decolorization of Methylene Blue with TiO2 Sol via UV Irradiation Photocatalytic Degradation

    OpenAIRE

    2010-01-01

    TiO2 sol was prepared for the degradation of methylene blue (MB) solution under ultraviolet (UV) irradiation. The absorption spectra of MB indicated that the maximum wavelength, 663 nm, almost kept the same. The performance of 92.3% for color removal was reached after 160 min. The particle size of TiO2 sol was about 22.5 nm. X-ray diffraction showed that TiO2 consisted of a single anatase phase. The small size and anatase phase probably resulted in high photocatalytic activity of TiO2 sol. Th...

  10. Radiolytically prepared Ni-Pd sols as catalysts for water photoreduction

    Energy Technology Data Exchange (ETDEWEB)

    Amouyal, E.; Georgopoulos, M.; Delcourt, M.O. (Paris-11 Univ., 91 - Orsay (FR). Lab. de Physico-Chimie des Rayonnements)

    1989-07-01

    Ni-Pd sols containing 10% Pd, prepared via radiolytic reduction, display a catalytic activity notably enhanced, compared to pure nickel sols, towards the water photoreduction to hydrogen. The test system is Ru(bipy){sub 3}{sup 2+}/methylviologen/N-phenylglycine: a favourable pH effect is shown at pH 2.5. Hydrogen evolution rate is not far from the optimal values obtained with platinum sols in acidic medium. These Ni-Pd aggregates are the first example of an aqueous colloid metal catalyst being improved by alloying effect.

  11. Feasibility study of silica sol as the carrier of a hydrophobic drug in aqueous solution using enrofloxacin as the model

    Energy Technology Data Exchange (ETDEWEB)

    Song Meirong, E-mail: smr770505@yahoo.com.cn [College of Sciences, Henan Agricultural University, Zhengzhou 450002 (China); Song Junling [School of Food, Henan Institute of Science and Technology, Xinxiang, 453003 (China); Ning Aimin [College of Sciences, Henan Agricultural University, Zhengzhou 450002 (China); Cui Baoan, E-mail: baoancui@henau.edu.cn [College of Sciences, Henan Agricultural University, Zhengzhou 450002 (China); Cui Shumin; Zhou Yaobing; An Wankai; Dong Xuesong; Zhang Gege [College of Sciences, Henan Agricultural University, Zhengzhou 450002 (China)

    2010-01-01

    The aim of this study was to determine the feasibility of using silica sol to carry a hydrophobic drug in aqueous solution. Enrofloxacin, which was selected as the model drug because it is a broad-spectrum antibiotic drug with poor solubility in water, was adsorbed onto silica sol in aqueous solution during cooling from 60 deg. C to room temperature. The drug-loaded silica sol was characterized by transmission electron microscopy, Fourier transform infrared spectrum, thermal gravimetric analysis and ultraviolet-visible light spectroscopy. The results showed that enrofloxacin was adsorbed by silica sol without degradation at a loading of 15.23 wt.%. In contrast to the rapid release from pure enrofloxacin, the drug-loaded silica sol showed a slower release over a longer time. Kinetics analysis suggested the drug release from silica sol was mainly a diffusion-controlled process. Therefore, silica sol can be used to carry a hydrophobic drug in aqueous solution for controlled drug delivery.

  12. Persistent improved results after adding vincristine and bleomycin to a cyclophosphamide/hydroxorubicin/Vm-26/prednisone combination (CHVmP) in stage III-IV intermediate- and high-grade non-Hodgkin's lymphoma. The EORTC Lymphoma Cooperative Group.

    Science.gov (United States)

    Meerwaldt, J H; Carde, P; Somers, R; Thomas, J; Kluin-Nelemans, J C; Bron, D; Noordijk, E M; Cosset, J M; Bijnens, L; Teodorovic, I; Hagenbeek, A

    1997-01-01

    CHOP has been and still is regarded by many as the 'standard' treatment of advanced non-Hodgkin's lymphoma. In 1980 the EORTC Lymphoma Cooperative Group started a study to evaluate the addition of vincristine and bleomycin to its standard four-drug combination chemotherapy, CHVmP (cyclophosphamide, hydroxorubicin, Vm-26, prednisone). Eligible patients were stage III or IV, intermediate- to high-grade non-Hodgkin's lymphoma (Working Formulation E-I). One-hundred-eighty-nine patients were entered, of whom 140 were eligible and evaluable. A previous report showed an improved response rate and failure-free survival (FFS) and overall survival for the combination CHVmP-VB. At ten years, the outcome still favors the addition of vincristine and bleomycin. The FFS was 34% vs. 23% and the overall survival 34% vs 22%. This difference was mainly due to a difference in CR rate (74% vs. 49%), Relapse-free survival for patients reaching a CR was the same in both arms. When the patients were grouped according to the International Prognostic Factor Index, no statistically significant difference could be observed in favor of one treatment within either group. This trial clearly demonstrates the benefit gained by the addition of vincristine and bleomycin to 'standard' chemotherapy for intermediate and high-grade non-Hodgkin's lymphoma.

  13. Properties of Zn O/Cr thin films prepared by Sol-Gel; Propiedades de peliculas delgadas ZnO/Cr preparadas por Sol-Gel

    Energy Technology Data Exchange (ETDEWEB)

    Tirado G, S.; Olvera A, R., E-mail: tirado@esfm.ipn.mx [IPN, Escuela Superior de Fisica y Matematicas, Edificio 9, Unidad Profesional A. L. M., San Pedro Zacatenco, 07788 Mexico D. F. (Mexico)

    2014-08-15

    Zn O films and those superficially modified with chromium were deposited on substrates of soda-lime glass, using the Sol-Gel process and the repeated immersion method. Starting from dehydrated zinc acetate was prepared a solution to 0.6 M to ambient temperature in 2-methoxyethanol and monoethanolamine (Mea) stirring magnetically. The Sol was prepared with an aging to seven days and was used to grow a films group with thickness to eight immersions. These same films were superficially modified with several depositions of a chromium nitrate Sol dissolved in ethanol to low concentration. The Zn O films were structurally characterized by X-ray diffraction, its chemical composition by energy dispersive X-ray spectroscopy and its morphology by scanning electron microscopy and atomic force microscopy, as well as their optical properties by UV-vis. Of the obtained results are proposed possible applications. (author)

  14. Molecular receptors in metal oxide sol-gel materials prepared via molecular imprinting

    Science.gov (United States)

    Sasaki, Darryl Y.; Brinker, C. Jeffrey; Ashley, Carol S.; Daitch, Charles E.; Shea, Kenneth J.; Rush, Daniel J.

    2000-01-01

    A method is provided for molecularly imprinting the surface of a sol-gel material, by forming a solution comprised of a sol-gel material, a solvent, an imprinting molecule, and a functionalizing siloxane monomer of the form Si(OR).sub.3-n X.sub.n, wherein n is an integer between zero and three and X is a functional group capable of reacting with the imprinting molecule, evaporating the solvent, and removing the imprinting molecule to form the molecularly imprinted metal oxide sol-gel material. The use of metal oxide sol-gels allows the material porosity, pore size, density, surface area, hardness, electrostatic charge, polarity, optical density, and surface hydrophobicity to be tailored and be employed as sensors and in catalytic and separations operations.

  15. Characterization and comparison of PZT powder synthesis by solid state and sol gel methods

    Directory of Open Access Journals (Sweden)

    E Pakizeh

    2012-09-01

    Full Text Available   This paper describes the synthesis of Pb(Zr0.95Ti0.05O3 powder by sol gel and solid state methods. PZT powders were fabricated by solid-state reaction process using metal oxides and in sol gel method salts and organic compounds were employed. The powders were calcined at 700 and 950 oC in sol gel and solid state methods, respectively. The synthesized powders were analyzed by FTIR and XRD. The average crystal grain size of PZT powders determined by X-ray diffraction method using the Scherrer equation, and in sol gel and solid state methods measured 42 and 330 nm, respectively. The optical constants of powders were evaluated and compaed using FTIR transmittance spectroscopy and Kramers-Kronig analysis.

  16. Download - eSOL | LSDB Archive [Life Science Database Archive metadata

    Lifescience Database Archive (English)

    Full Text Available switchLanguage; BLAST Search Image Search Home About Archive Update History Data ...Database Description Download License Update History of This Database Site Policy | Contact Us Download - eSOL | LSDB Archive ...

  17. Sol-Rad Net Flux (L 1.0, 1.5, 2.0)

    Data.gov (United States)

    National Aeronautics and Space Administration — SolRad-Net (Solar Radiation Network) is an established network of ground-based sensors providing high-frequency solar flux measurements in quasi-realtime to the...

  18. Preparation of oxide glasses from metal alkoxides by sol-gel method

    Science.gov (United States)

    Kamiya, K.; Yoko, T.; Sakka, S.

    1987-01-01

    An investigation is carried out on the types of siloxane polymers produced in the course of the hydrolysis of silicon tetraethoxide, as well as the preparation of oxide glasses from metal alkoxides by the sol-gel method.

  19. Amoeba-like self-oscillating polymeric fluids with autonomous sol-gel transition

    Science.gov (United States)

    Onoda, Michika; Ueki, Takeshi; Tamate, Ryota; Shibayama, Mitsuhiro; Yoshida, Ryo

    2017-07-01

    In the field of polymer science, many kinds of polymeric material systems that show a sol-gel transition have been created. However, most systems are unidirectional stimuli-responsive systems that require physical signals such as a change in temperature. Here, we report on the design of a block copolymer solution that undergoes autonomous and periodic sol-gel transition under constant conditions without any on-off switching through external stimuli. The amplitude of this self-oscillation of the viscosity is about 2,000 mPa s. We also demonstrate an intermittent forward motion of a droplet of the polymer solution synchronized with the autonomous sol-gel transition. This polymer solution bears the potential to become the base for a type of slime-like soft robot that can transform its shape kaleidoscopically and move autonomously, which is associated with the living amoeba that moves forward by a repeated sol-gel transition.

  20. Optical pH detector based on LTCC and sol-gel technologies

    Science.gov (United States)

    Tadaszak, R. J.; Łukowiak, A.; Golonka, L. J.

    2013-01-01

    This paper presents an investigation on using sol-gel thin film as a material for sensors application in LTCC (Low Temperature Co-fired Ceramics) technology. This material gives the opportunity to make new, low-cost highly integrated optoelectronic devices. Sensors with optical detection are a significant part of these applications. They can be used for quick and safe diagnostics of some parameters. Authors present a pH detector with the optical detection system made of the LTCC material. The main part of the device is a flow channel with the chamber and sol-gel active material. The silica sol-gel with bromocresol green indicator was used. As the absorbance of sol-gel layer changes with the pH value of a measured medium, the transmitted light power was measured. The pH detector was integrated with the electronic components on the LTCC substrate.

  1. Preparation and Characterization of M-Type Barium Ferrite Fibers via Aqueous Sol-Gel Process

    Institute of Scientific and Technical Information of China (English)

    GONG Cairong; FAN Guoliang; SONG Chonglin; L(U) Gang

    2007-01-01

    BaFe12O19 fibers was prepared via an aqueous sol-gel process using Fe(OH)( HCOO)2 synthesized in laboratory and Ba(CH3COO)2 as the original materials and citrate as the chelate. The rheological behaviour of spinnable sol was characterized on rheometer, and the development of gel fibers to barium ferrite fibers was studied by IR, TG and XRD. Morphology observation of the fibers was given on SEM, and the diameter of the obtained fibers was between 5 and 10 μm corresponding to different additives. The additives affected the surface tension of the precursor sol which had close relation to the microstructure of fibers. Sucrose and hydroxyethylic cellulose could improve the surface tension while diethanolamine and hexadecylamine reduce that of the precursor sol. And using diethanolamine or hexadecylamine as an additive, well-structured BaFe12O19 fibers could be obtained.

  2. Enhanced piezoelectric performance of composite sol-gel thick films evaluated using piezoresponse force microscopy.

    Science.gov (United States)

    Liu, Yuanming; Lam, Kwok Ho; Kirk Shung, K; Li, Jiangyu; Zhou, Qifa

    2013-05-14

    Conventional composite sol-gel method has been modified to enhance the piezoelectric performance of ceramic thick films. Lead zirconate titanate (PZT) and lead magnesium niobate-lead titanate (PMN-PT) thick films were fabricated using the modified sol-gel method for ultrasonic transducer applications. In this work, piezoresponse force microscopy was employed to evaluate the piezoelectric characteristics of PZT and PMN-PT composite sol-gel thick films. The images of the piezoelectric response and the strain-electric field hysteresis loop behavior were measured. The effective piezoelectric coefficient (d33,eff) of the films was determined from the measured loop data. It was found that the effective local piezoelectric coefficient of both PZT and PMN-PT composite films is comparable to that of their bulk ceramics. The promising results suggest that the modified composite sol-gel method is a promising way to prepare the high-quality, crack-free ceramic thick films.

  3. Discrimination of Sol and Gel states in an aging clay suspension

    Science.gov (United States)

    Shayeganfar, F.; Sadegh Movahed, M.; Jafari, G. R.

    2013-09-01

    The dynamical scattered light intensity and multiplicative cascade model was employed to characterize the anisotropic charged colloidal particles suspension during the so-called Sol-Gel transition. Generally we looked for finding a criterion to distinguish the properties of Sol and Gel states systematically. The probability density function (PDF) of the light scattering intensity shows an obvious change with proceeding of the sample aging process (during of gelation state). Our results confirmed that in the so-called Sol state, the value of non-Gaussian parameter, λw2, as a function of time is larger than that of for weak-Gel or in coexistence Sol-Gel state. The number of cascades in the weak-Gel is smaller than the rest of states. In addition, we found out a deviation from Kolmogorov-Obukhov hypothesis concerning the linear dependance of λw2 to the logarithm of scale.

  4. [Use of silver sols as markers for immunoassay on microtiter plates].

    Science.gov (United States)

    Poltavchenko, A G; Karavaev, V S; Tuzikov, F V

    1998-01-01

    Some basic characteristics of silver sols, facilitating their use as possible markers for the enzyme immunoassay on microtitration plates, were studied. Dispersion characteristics of silver sols obtained from AgNO3 solutions with a concentration of 0.005-0.5%, as well as the efficiency of their detection with physical developers on the basis of methol, paraphenylene diamine and amidol, were determined. The aggregative stability of the sol and the protective effect of a number of nonionic detergents, synthetic and biopolymeric, were evaluated. Similar sensitivity at the level of 1 ng/ml was attained in the comparative detection of lgG adsorbed on microtitration plates with the use of immunoperoxidase conjugate and silver immunosols. The possibility of using silver sols in the enzyme immunoassay as an alternative to enzymatic markers was shown.

  5. Foliar application of two silica sols reduced cadmium accumulation in rice grains.

    Science.gov (United States)

    Liu, Chuanping; Li, Fangbai; Luo, Chunling; Liu, Xinming; Wang, Shihua; Liu, Tongxu; Li, Xiangdong

    2009-01-30

    In the present study, pot experiments were conducted to investigate the effects of foliar application of two silica (Si) sols on the alleviation of cadmium (Cd) toxicity in contaminated soil to rice. Results showed that the foliar application of Si sols significantly increased the dry weight of grains (without husk) and shoots in rice grown in Cd contaminated soil, whereas the Cd concentration in the grains and shoots decreased obviously. The total accumulation of Cd in rice grains also decreased with the application of both of the Si sols, but no significant effect was found on the Cd accumulation in the shoots. For the optimal effect, Si-sol-B should be foliar applied at the tillering-stage during rice growth. The mechanism of Si foliar application to alleviate the toxicity and accumulation of Cd in grains of rice may be related to the probable Cd sequestration in the shoot cell walls.

  6. Microstructure Control of Nanoporous Silica Thin Film Prepared by Sol-gel Process

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Nanoporous silica films were prepared by sol-gel process with base, acid and base/acid two-step catalysis.Transmission electron microscope (TEM) and particle size analyzer were used to characterize the microstructure and the particle size distribution of the sols. Scanning electron microscopy (SEM), atomic force microscopy (AFM) and spectroscopic ellipsometer were used to characterize the surface microstructure and the optical properties of the silica films. Stability of the sols during long-term storage was investigated. Moreover,the dispersion relation of the optical constants of the silica films, and the control of the microstructure and properties of the films by changing the catalysis conditions during sol-gel process were also discussed.

  7. Application of polyaniline/sol-gel derived tetraethylorthosilicate films to an amperometric lactate biosensor.

    Science.gov (United States)

    Chaubey, Asha; Pande, K K; Malhotra, B D

    2003-11-01

    The electrochemical entrapment of polyaniline (PANI) onto sol-gel derived tetraethylorthosilicate (TEOS) films deposited onto indium-tin-oxide (ITO) coated glass has been utilized for immobilization of lactate dehydrogenase (LDH). The performance of these sol-gel/PANI/LDH electrodes has been investigated as a function of the lactate concentration, applied potential, pH of the medium and interferents. The amperometric response of the electrodes under optimum conditions exhibited a linear relationship from 1 mM to 4 mM. An attempt has been made to extend the linearity up to 10 mM for lactate by coating an external layer of polyvinyl chloride (PVC) over the sol-gel/PANI/LDH electrodes with a correlation coefficient of 0.89. These sol-gel/PANI/LDH electrodes have a response time of about 60 s, a shelf life of about 8 weeks at 0-4 degrees C and have implications in a lactate biosensor.

  8. Overview Of 100 Sols Of Chemcam Operations At Gale Crater

    Science.gov (United States)

    Maurice, Sylvestre; Wiens, Roger; MSL Science Team

    2013-04-01

    The Curiosity rover carries the ChemCam instrument suite, a Laser-Induced Breakdown Spectroscopy (LIBS) instrument that can analyze the chemical composition of geological samples at distances up to 7 meters from the rover, and a high resolution camera for context imaging (RMI). In the first 100 sols after landing, ChemCam performed 343 single point measurements on approximately 50 different rocks or soil areas, for over 12,000 laser shots. Each time at least two RMI images are acquired before and after the laser shots to visualize the area of investigation and the geological context. LIBS lines are identified using primarily a martian dedicated database; to date, ChemCam has detected unambiguously major elements (Si, Al, Fe, Mg, Ca, Na, K, O), minor/trace elements of interest (Li, Cr, Mn, Rb, Sr, Ba, Ti, S, C, H). These observations allow a qualitative/quantitative assessment of the presence of dust (first few shots), the sample surface composition and chemical heterogeneity with depth. Several techniques have been developed to analyze ChemCam's data: (1) Univariate analysis refers to peak height studies of well-chosen LIBS lines and a training dataset to build calibration curves. Peak ratios K/Si, Na/Si, Al/Si, Fe+Mg/Si, or Mg/Mg+Fe have been calculated from the onboard calibration targets. The technique also applies to minor and trace elements which yield low intensity emission lines, such as Lin, Rb, H, C. (2) Multivariate methods give better results in terms of elemental composition, since they examine simultaneously and statistically several peaks of the same elements. A Partial Least Squares (PLS) regression algorithm is used for rapid major-element abundance determination. (3) Composition trends, clusters and end-members can also be identified using component analysis methods. Independent Component Analysis (ICA) identifies components that are directly related to Chemical elements: Al, Ca, Fe, H, K, Mg, Na, O, Si, Ti, but also mixture like a "soil" component

  9. Durable flame retardant finish for silk fabric using boron hybrid silica sol

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Qiang-hua; Gu, Jiali; Chen, Guo-qiang [National Engineering Laboratory for Modern Silk, Soochow University (China); Xing, Tie-ling, E-mail: xingtieling@suda.edu.cn [National Engineering Laboratory for Modern Silk, Soochow University (China); Jiangsu HuaJia Group (China)

    2016-11-30

    Highlights: • Highly homogeneous boron hybrid silica sol flame retardant system was prepared through sol-gel method. • The silk samples treated and cross-linked by this hybrid sol and BTCA solution showed a higher limiting oxygen index (LOI) more than 31.0% and a better washing durability for more than 30 times washing. • The smoke suppression, combustion performance and thermal stability properties of the treated samples have a significant improvement. - Abstract: A hybrid silica sol was prepared via sol gel method using tetraethoxysilane (TEOS) as a precursor and boric acid (H{sub 3}BO{sub 3}) as flame retardant additive and then applied to silk fabric. In order to endow silk fabric with durable flame retardancy, 1,2,3,4-butanetetracarboxylic acid (BTCA) was used as cross-linking agent for the sake of strong linkage formation between the hybrid silica sol and silk fabric. The FT-IR and XPS analysis demonstrated the Si-O-B formation in the sol system, as well as the linkage between the sol and silk after the treatment. The limiting oxygen index (LOI) and smoke density test indicated good flame retardancy and smoke suppression of the treated silk fabrics. The micro calorimeter combustion (MCC) test and thermo gravimetric (TG) analysis showed that the treated samples had less weight loss in the high temperature and lower heat release rate when burning. The washing durability evaluation results indicated that there was a distinct improvement for the silk samples treated with BTCA even after 30 times washing. In addition, the influence of the processing order of BTCA and silica sol treatment on the limiting oxygen index (LOI) of the finished silk fabric was also investigated. And the results demonstrated that the sample treated with BTCA first and then with the silica sol exhibited better LOI value (32.3%) than that of the sample by the conversed treatment order. Moreover the tensile property of treated samples was nearly unchanged, but the handle of sol treated

  10. Strength of interactions between immobilized dye molecules and sol-gel matrices.

    Science.gov (United States)

    Ismail, Fanya; Schoenleber, Monika; Mansour, Rolan; Bastani, Behnam; Fielden, Peter; Goddard, Nicholas J

    2011-02-21

    In this paper we present a new theory to re-examine the immobilization technique of dye doped sol-gel films, define the strength and types of possible bonds between the immobilized molecule and sol-gel glass, and show that the immobilized molecule is not free inside the pores as was previously thought. Immobilizing three different pH sensitive dyes with different size and functional groups inside the same sol-gel films revealed important information about the nature of the interaction between the doped molecule and the sol-gel matrix. The samples were characterized by means of ultraviolet-visible spectrophotometer (UV-VIS), thermal gravimetric analysis (TGA), mercury porosimetry (MP), nuclear magnetic resonance spectroscopy ((29)Si NMR) and field-emission environmental scanning electron microscopy (ESEM-FEG). It was found that the doped molecule itself has a great effect on the strength and types of the bonds. A number of factors were identified, such as number and types of the functional groups, overall charge, size, pK(a) and number of the silanol groups which surround the immobilized molecule. These results were confirmed by the successful immobilization of bromocresol green (BCG) after a completely polymerized sol-gel was made. The sol-gel consisted of 50% tetraethoxysilane (TEOS) and 50% methyltriethoxysilane (MTEOS) (w/w). Moreover, the effect of the immobilized molecule on the structure of the sol-gel was studied by means of a leaky waveguide (LW) mode for doped films made before and after polymerization of the sol-gel.

  11. The language and learning study (SOL): Study profile and results so far

    OpenAIRE

    Wang Mari Vaage; Synnve Schjølberg

    2014-01-01

    Language development is associated with cognitive, social and behavioral performance. A healthy language development is crucial for everyday functioning both during childhood and in adulthood. Language impairment is considered one of the most common neurodevelopmental impairments in children. The language and learning study (SOL) is a platform for multiple language projects. The main aim of SOL is to provide the best possible knowledge base for understanding causes and developmental trajector...

  12. Making MgO/SiO2 Glasses By The Sol-Gel Process

    Science.gov (United States)

    Bansal, Narottam P.

    1989-01-01

    Silicon dioxide glasses containing 15 mole percent magnesium oxide prepared by sol-gel process. Not made by conventional melting because ingredients immiscible liquids. Synthesis of MgO/SiO2 glass starts with mixing of magnesium nitrate hexahydrate with silicon tetraethoxide, both in alcohol. Water added, and transparent gel forms. Subsequent processing converts gel into glass. Besides producing glasses of new composition at lower processing temperatures, sol-gel method leads to improved homogeneity and higher purity.

  13. CHARACTERIZATION OF BRANCHING POINT DISTRIBUTION IN THE SOL OF IRRADIATED POLYSTYRENE WITH SEC-LALLS

    Institute of Scientific and Technical Information of China (English)

    ZHANG Wanxi; WANG Mouzhi; SUN Jiazhen

    1991-01-01

    In this paper, the change behavior of branching point distribution of irradiated polystyrene in sol has been first studied by the SEC-LALLS method. The experimental results show that branching parameter of the part with lower molecular weight in the sol changes little at the early stage of irradiation and that of the part with the higher molecular weight becomes greater with the increase in radiation dose.

  14. Evolution of microstructure in mixed niobia-hybrid silica thin films from sol-gel precursors.

    Science.gov (United States)

    Besselink, Rogier; Stawski, Tomasz M; Castricum, Hessel L; ten Elshof, Johan E

    2013-08-15

    The evolution of structure in sol-gel derived mixed bridged silsesquioxane-niobium alkoxide sols and drying thin films was monitored in situ by small-angle X-ray scattering. Since sol-gel condensation of metal alkoxides proceeds much faster than that of silicon alkoxides, the incorporation of d-block metal dopants into silica typically leads to formation of densely packed nano-sized metal oxide clusters that we refer as metal oxide building blocks in a silica-based matrix. SAXS was used to study the process of niobia building block formation while drying the sol as a thin film at 40-80°C. The SAXS curves of mixed niobia-hybrid silica sols were dominated by the electron density contrast between sol particles and surrounding solvent. As the solvent evaporated and the sol particles approached each other, a correlation peak emerged. Since TEM microscopy revealed the absence of mesopores, the correlation peak was caused by a heterogeneous system of electron-rich regions and electron poor regions. The regions were assigned to small clusters that are rich in niobium and which are dispersed in a matrix that mainly consisted of hybrid silica. The correlation peak was associated with the typical distances between the electron dense clusters and corresponded with distances in real space of 1-3 nm. A relationship between the prehydrolysis time of the silica precursor and the size of the niobia building blocks was observed. When 1,2-bis(triethoxysilyl)ethane was first hydrolyzed for 30 min before adding niobium penta-ethoxide, the niobia building blocks reached a radius of 0.4 nm. Simultaneous hydrolysis of the two precursors resulted in somewhat larger average building block radii of 0.5-0.6 nm. This study shows that acid-catalyzed sol-gel polymerization of mixed hybrid silica niobium alkoxides can be rationalized and optimized by monitoring the structural evolution using time-resolved SAXS.

  15. determinisme de la stabilite structurale des sols cultives de la zone ...

    African Journals Online (AJOL)

    ACSS

    7 août 2017 ... organiques du sol ont été significativement influencées par les systèmes de culture et corrélées ... maintenir une couverture végétale vivante à la surface de ces sols en vue d'affermir leur état structural. ...... Fruits 30:595-612.

  16. Mixed Pyridine-phenol Boron Complex Encapsulated in Polymer/Silica Hybrid Sol-gel Matrix

    Institute of Scientific and Technical Information of China (English)

    DONG Wei; TANG Jun; WANG Yue

    2008-01-01

    A novel pyridine-phenol boron complex[(dppy)BF]was encapsulated into polymer/silica composite matrix by sol-gel process.UV-Vis absorption spectra show that this process can control the aggregation structure of complex(dppy)BF.The results of photoluminescence of(dppy)BF in sol-gel composite film indicate that both fluorescence intensity and photostability are markedly increased using this method compared with other methods,which increases the practical significance of such composite film.

  17. Durable flame retardant finish for silk fabric using boron hybrid silica sol

    Science.gov (United States)

    Zhang, Qiang-hua; Gu, Jiali; Chen, Guo-qiang; Xing, Tie-ling

    2016-11-01

    A hybrid silica sol was prepared via sol gel method using tetraethoxysilane (TEOS) as a precursor and boric acid (H3BO3) as flame retardant additive and then applied to silk fabric. In order to endow silk fabric with durable flame retardancy, 1,2,3,4-butanetetracarboxylic acid (BTCA) was used as cross-linking agent for the sake of strong linkage formation between the hybrid silica sol and silk fabric. The FT-IR and XPS analysis demonstrated the Si-O-B formation in the sol system, as well as the linkage between the sol and silk after the treatment. The limiting oxygen index (LOI) and smoke density test indicated good flame retardancy and smoke suppression of the treated silk fabrics. The micro calorimeter combustion (MCC) test and thermo gravimetric (TG) analysis showed that the treated samples had less weight loss in the high temperature and lower heat release rate when burning. The washing durability evaluation results indicated that there was a distinct improvement for the silk samples treated with BTCA even after 30 times washing. In addition, the influence of the processing order of BTCA and silica sol treatment on the limiting oxygen index (LOI) of the finished silk fabric was also investigated. And the results demonstrated that the sample treated with BTCA first and then with the silica sol exhibited better LOI value (32.3%) than that of the sample by the conversed treatment order. Moreover the tensile property of treated samples was nearly unchanged, but the handle of sol treated samples obviously decreased.

  18. Pharmacognostical Studies of the Pericarp of Lagonychium farctum (Banks and Sol. Bobr. Growing in Egypt

    Directory of Open Access Journals (Sweden)

    Ashraf N. E. Hamed

    2013-03-01

    Full Text Available Lagonychium farctum (Banks and Sol. Bobr. is an erect prickly trees or shrubs. It belongs to family Leguminosae. It is used in traditional system of medicine as an astringent as well as anti-dysenteric. The present study investigates various standardized parameters such as macroscopic and microscopic characters which could be helpful in authentication of the pericarp of Lagonychium farctum. (Banks & Sol. Bobr

  19. The Research on Tetracthoxysilane(TEOS)and its Application in Sol Gel%正硅酸乙酯(TEOS)的Sol-Gel法应用研究

    Institute of Scientific and Technical Information of China (English)

    廖辉伟

    2004-01-01

    介绍并讨论了正硅酸乙酯及其在Sol-Gel法中的应用研究.各类功能新材料制备与应用研究是目前材料科学领域研究的重点,正硅酸乙酯作为新材料合成常用的前驱体,受到人们的高度关注, 合成制备中常采用Sol-Gel法.

  20. Sol-Gel法制备SiO2膜的研究进展%The Progress of Sol-Gel Derived Silica Membranes

    Institute of Scientific and Technical Information of China (English)

    郭文淼; 金珊

    2003-01-01

    叙述了Sol-Gel法制备SiO2膜的原理以及工艺;举例说明了近些年来SiO2膜的制备进展,讨论了SiO2膜制备过程的影响因素;进而指出了采用Sol-Gel制备SiO2膜存在的问题.为SiO2膜的制备提供参考.

  1. Sol-Gel法制备PZT铁电薄膜新进展%Advances of sol-gel derivation of PZT ferroelectric thin films

    Institute of Scientific and Technical Information of China (English)

    王福平; 姜兆华; 于艳菊; 赵连城

    2001-01-01

    从底电极的选择、过渡层的引入、外延膜的生长、取代阳离子的改性四个方面介绍了Sol-Gel法制备PZT铁电薄膜的研究进展,简述了PZT的Sol-Gel机理研究现状和引起PZT铁电薄膜极化疲劳的原因,分析了Sol-Gel法制备PZT铁电薄膜研究中存在的问题,并提出展望.

  2. Effects of sol aging on resistive switching behaviors of HfO{sub x} resistive memories

    Energy Technology Data Exchange (ETDEWEB)

    Hsu, Chih-Chieh, E-mail: cchsu@yuntech.edu.tw [Graduate School of Engineering Science and Technology, National Yunlin University of Science and Technology, Douliu 64002, Taiwan, ROC (China); Department of Electronic Engineering, National Yunlin University of Science and Technology, Douliu 64002, Taiwan, ROC (China); Graduate School of Electronic Engineering, National Yunlin University of Science and Technology, Douliu 64002, Taiwan, ROC (China); Sun, Jhen-Kai; Tsao, Che-Chang; Chen, Yu-Ting [Graduate School of Electronic Engineering, National Yunlin University of Science and Technology, Douliu 64002, Taiwan, ROC (China)

    2017-03-01

    This work investigates effects of long-term sol-aging time on sol-gel HfO{sub x} resistive random access memories (RRAMs). A nontoxic solvent of ethanol is used to replace toxic 2-methoxyethanol, which is usually used in sol-gel processes. The top electrodes are fabricated by pressing indium balls onto the HfO{sub x} surface rather than by using conventional sputtering or evaporation processes. The maximum process temperature is limited to be 100 ℃. Therefore, influences of plasma and high temperature on HfO{sub x} film can be avoided. Under this circumstance, effects of sol aging time on the HfO{sub x} films can be more clearly studied. The current conduction mechanisms in low and high electric regions of the HfO{sub x} RRAM are found to be dominated by Ohmic conduction and trap-filled space charge limited conduction (TF-SCLC), respectively. When the sol aging time increases, the resistive switching characteristic of the HfO{sub x} layer becomes unstable and the transition voltage from Ohmic conduction to TF-SCLC is also increased. This suggests that an exceedingly long aging time will give a HfO{sub x} film with more defect states. The XPS results are consistent with FTIR analysis and they can further explain the unstable HfO{sub x} resistive switching characteristic induced by sol aging.

  3. Investigation on a Sol-gel Coating Containing Inhibitors on 2024-T3 Aluminum Alloy

    Institute of Scientific and Technical Information of China (English)

    SHI Hong-wei; LIU Fu-chun; HAN En-hou; SUN Ming-cheng

    2006-01-01

    For a long time, chromate incorporated conversion coatings have been drawn special attention in corrosion protection of aircraft-used aluminum alloys. However,ever-increasing environmental pressures requires that non-chromate conversion coatings be developed because of the detrimental carcinogenic effects of the chromate compounds. In recent years, the sol-gel coatings doped with inhibitors were developed to replace chromate conversion coatings, and showed real promise. A sol-gel coating was prepared and its anti-corrosion behavior was investigated using the potentiodynamic scanning (PDS) and the electrochemical impedance spectroscopy (EIS). It is found that the sol-gel coating obtained by the hydrolysis and condensation of 3-glycidoxypropyltrimethoxysilane (GPTMS) and tetramethoxysilane (TMOS) is prone to form defects if cured at the room temperature, whereas if cured at a higher temperature (100 ℃), these flaws can be avoided. Furthermore, it can be seen that addition of anti-foam agents and surfactants will reduce the faults if cured at the room temperature. Effects of the corrosion inhibitors, CeCl3 and mercaptobenzothiazole (MBT), in the sol-gel coatings on 2024-T3 aluminum alloy were also investigated. Results show that the corrosion resistance of the sol-gel coatings containing CeCl3 proves to be better than that of the pure and MBT added sol-gel coatings by the electrochemical methods.

  4. EPR Spectroscopy of Different Sol Concentration Synthesized Nanocrystalline-ZnO Thin Films

    Directory of Open Access Journals (Sweden)

    Manju Arora

    2015-01-01

    Full Text Available Nanocrystalline zinc oxide (nc-ZnO thin films were grown on p-type silicon substrate through spin coating by sol-gel process using different sol concentrations (10 wt.%, 15 wt.%, and 25 wt.%. These films were characterized by high resolution nondestructive X-ray diffraction (XRD, scanning electron microscopy (SEM with energy dispersive X-ray analysis (EDS attachment, and electron paramagnetic resonance (EPR techniques to understand variations in structural, morphological, and oxygen vacancy with respect to sol concentration. The film surface morphology changes from nanowall to nanorods on increasing sol concentration. EPR spectra revealed the systematic variation from ferromagnetic to paramagnetic nature in these nc-ZnO films. The broad EPR resonance signal arising from the strong dipolar-dipolar interactions among impurity defects present in nc-ZnO film deposited from 10 wt.% sol has been observed and a single strong narrow resonance signal pertaining to oxygen vacancies is obtained in 25 wt.% sol derived nc-ZnO film. The concentrations of impurity defects and oxygen vacancies are evaluated from EPR spectra, necessary for efficient optoelectronic devices development.

  5. Effect of Variant Counterions on Stability and Particle Size of Silica Sol

    Institute of Scientific and Technical Information of China (English)

    PAN, Ming-Chu; YANG, Yu-Xiang; YING, Hai-Ping; JIA, Xiang-Chen; CHEN, Ya-Ru; TANG, Yue

    2007-01-01

    The effects of variant counterions with ionic strength of 0.05, 0.10, 0.20 and 0.25 mol·kg-1 on the stability and particle size of silica sols have been studied using the traditional methods of Ubbelohde viscosity measurement, TEM and titration respectively, finding that the stability and particle size of the silica sols are all concerned with the acidic, positively electric properties and the sizes of the counterions, as well as the attraction between the counteri ons and surface silicon hydroxyl groups of the silica sols. The small positively charged counterions lead to the de crease in particle sizes, making the silica sol the most stable. But the larger weakly acidic counterions can restrict the particle sizes of the silica sols and easily make the sols coagulate. It was also found that there existed a linear relationship between log r and log η, which has not ever been reported. The effect of temperature on the stability and particle sizes was also discussed.

  6. Preparation and characterization of conductive and transparent ruthenium dioxide sol-gel films.

    Science.gov (United States)

    Allhusen, John S; Conboy, John C

    2013-11-27

    RuO2 conductive thin films were synthesized using the sol-gel method and deposited onto transparent insulating substrates. The optical transmission, film thickness, surface morphology and composition, resistivity, and spectroelectrochemical performance have been characterized. The optical transmission values of these films ranged from 70 to 89% in the visible region and from 56 to 88% in the infrared region. Resistivity values of the RuO2 sol-gel films varied from 1.02 × 10(-3) to 1.13 Ω cm and are highly dependent on the initial solution concentration of RuO2 in the sol-gel. The RuO2 sol-gel films were used as electrodes for the electrochemical oxidation and reduction of ferrocenemethanol. The electrochemical behavior of our novel RuO2 sol-gel films was compared to that of a standard platinum disk electrode and showed no appreciable differences in the half-wave potential (E1/2). The mechanical and chemical stability of the coatings was tested by physical abrasion and exposure to highly acidic, oxidizing Piranha solution. Repeated exposure to these extreme conditions did not result in any appreciable decline in electrochemical performance. Finally, the use of the novel RuO2 sol-gel conductive and transparent films was demonstrated in a spectroelectrochemistry experiment in which the oxidation and reduction of ferrocenemethanol was monitored via UV-vis spectroscopy as the applied potential was cycled.

  7. Robust aptamer sol-gel solid phase microextraction of very polar adenosine from human plasma.

    Science.gov (United States)

    Mu, Li; Hu, Xiangang; Wen, Jianping; Zhou, Qixing

    2013-03-01

    Conventional solid phase microextraction (SPME) has a limited capacity to extract very polar analytes, such as adenosine. To solve this problem, aptamer conjugating sol-gel methodology was coupled with an SPME fiber. According to the authors' knowledge, this is the first reported use of aptamer SPME. The fiber of aptamer sol-gel SPME with a mesoporous structure has high porosity, large surface area, and small water contact angle. Rather than employing direct entrapment, covalent immobilization was the dominant method of aptamer loading in sol-gel. Aptamer sol-gel fiber captured a specified analyte from among the analog molecules, thereby, exhibiting an excellent selective property. Compared with commercial SPME fibers, this aptamer fiber was suitable for extracting adenosine, presenting an extraction efficiency higher than 20-fold. The values of repeatability and reproducibility expressed by relative standard deviation were low (9.4%). Interestingly, the sol-gel network enhanced the resistance of aptamer SPME to both nuclease and nonspecific proteins. Furthermore, the aptamer sol-gel fiber was applied in human plasma with LOQ 1.5 μg/L, which is an acceptable level. This fiber also demonstrates durability and regeneration over 20-cycles without significant loss of efficiency. Given the various targets (from metal ions to biomacromolecules and cells) of aptamers, this methodology will extend the multi-domain applications of SPME.

  8. Rationale and Design of the Echocardiographic Study of Hispanics / Latinos (ECHO-SOL)

    Science.gov (United States)

    Rodriguez, Carlos J.; Dharod, Ajay; Allison, Matthew A.; Shah, Sanjiv J.; Hurwitz, Barry; Bangdiwala, Shrikant I.; Gonzalez, Franklyn; Kitzman, Dalane; Gillam, Linda; Spevack, Daniel; Dadhania, Rupal; Langdon, Sarah; Kaplan, Robert

    2015-01-01

    Background Information regarding the prevalence and determinants of cardiac structure and function (systolic and diastolic) among the various Hispanic background groups in the United States is limited. Methods and Results The Echocardiographic Study of Latinos (ECHO-SOL) ancillary study recruited 1,824 participants through a stratified-sampling process representative of the population-based Hispanic Communities Health Study – Study of Latinos (HCHS-SOL) across four sites (Bronx, NY; Chicago, Ill; San Diego, Calif; Miami, Fla). The HCHS-SOL baseline cohort did not include an echo exam. ECHO-SOL added the echocardiographic assessment of cardiac structure and function to an array of existing HCHS-SOL baseline clinical, psychosocial, and socioeconomic data and provides sufficient statistical power for comparisons among the Hispanic subgroups. Standard two-dimensional (2D) echocardiography protocol, including M-mode, spectral, color and tissue Doppler study was performed. The main objectives were to: 1) characterize cardiac structure and function and its determinants among Hispanics and Hispanic subgroups; and 2) determine the contributions of specific psychosocial factors (acculturation and familismo) to cardiac structure and function among Hispanics. Conclusion We describe the design, methods and rationale of currently the largest and most comprehensive study of cardiac structure and function exclusively among US Hispanics. ECHO-SOL aims to enhance our understanding of Hispanic cardiovascular health as well as help untangle the relative importance of Hispanic subgroup heterogeneity and sociocultural factors on cardiac structure and function. (Ethn Dis. 2015;25[2]:180–186) PMID:26118146

  9. Preparation and the antibacterial activity of silver-loaded Chitosan-grafted-vanillin sol

    Directory of Open Access Journals (Sweden)

    Jing AN

    2016-08-01

    Full Text Available In order to enhance the antibacterial activity of chitosan and expand its application field, silver nanoparticles are introduced into the matrix, and the grafting modification is carried out. Chitosan grafted vanillin (CS-g-VA is prepared with microwave-radiation method, and silver nitrate is reduced by vanillin, so that silver nanoparticles are separated evenly in CS-g-VA sol, which is Ag/CS-g-VA composite sol. The effects on the preparation of Ag/CS-g-VA composite sol are studied, and the structure and thermal property of the obtained composite sol are characterized by SEM, TEM, FTIR, XRD, UV-vis and TG-DSC. The experiment results show that the optimum conditions for the preparation of Ag/CS-g-VA are as following: Vanillin concentration of 6.0%, CS-g-VA concentration of 4.0%, and silver nitrate concentration of 0.20 mol/L. The inhibition of Ag/CS-g-VA composite sol against Escherichia coli and Bacillus subtilis is investigated through antibacterial tests. The results show that the antibacterial activity of Ag/CS-g-VA composite sol is more efficient than that of single CS materials.

  10. Silica nanoparticle sols 1. Surface chemical characterization and evaluation of the foam generation (foamability).

    Science.gov (United States)

    Blute, Irena; Pugh, Robert J; van de Pas, John; Callaghan, Ian

    2007-09-15

    Surface characterization and foaming studies were carried out with nine industrially manufactured, colloidal silica dispersions with particles sizes from 5-40 nm. All the silica sols produced transient foams with short decay times and the dynamic foam generation (foamability) was found to vary according to the sol type with the greatest foamability occurring for the hydrophobically modified sol and the deionized hydrophilic sol. However, it was found that improved foamability of all the sols could be achieved by changing the pH to within the region of the pH(pzc) which corresponds to the region of lowest hydrophilicity. An increase in pH (and build-up of negative charge) enhances the surface hydrophilicity and caused a decrease in foamability. In addition, for selected hydrophilic sols, it was shown that the foamability (a) increased with decrease in particle size (within the 6-40 nm range) and (b) increased with particle concentration (within the range of 1-15 wt%). Overall, it was concluded that the foamability was primary controlled by hydrophobicity (and hence by pH) and also by the particle concentration, the particle size and the degree of agglomeration.

  11. Thermosensitive periodontal sol of ciprofloxacin hydrochloride and serratiopeptidase: Pharmaceutical and mechanical analysis.

    Science.gov (United States)

    Singh, Kushal Pal; Chhabra, Gulshan; Sharma, Vijay; Pathak, Kamla

    2014-01-01

    The aim of the present work was to explore the development of a dual-controlled release periodontal system of a potent broad spectrum first-generation fluoroquinolone, ciprofloxacin, and the anti-inflammatory enzyme serratiopeptidase (STP). Based on 3(2) full factorial design, thermoreversible periodontal sols capable of controlled dual delivery of ciprofloxacin hydrochloride and STP were designed using pluronic F127 and carbopol 934P as thermosensitive gelling polymers. Sol gel transition characteristics, %cumulative drug release at 48(th) h and exvivo mucoadhesive strength were designated as dependent responses. The sols were mucoadhesive, syringeable, and inverted into gels at simulated periodontal cavity temperature. F9 with optimal drug release was identified as the best formulation. Extra design check point generated using Design Expert software 8.02 (Stat-Ease, USA) validated the experimental design. Textural analysis revealed that the developed sols were syringeable and spreadable enough for periodontal treatment so it can be expected that hardness and compressibility of sols would pose no problem during clinical application. The in vitro release behavior exhibited controlled release of both cipro HCl and STP (>90% release). A dual-controlled release thermoreversible periodontal sol of ciproflaxin and STP was successfully developed. Incorporation of STP as anti-inflammatory agent has the potential of developing a therapeutically efficacious system of cipro HCl for treatment of periodontal inflammatory anaerobic infections.

  12. One-step sol-gel imprint lithography for guided-mode resonance structures.

    Science.gov (United States)

    Huang, Yin; Liu, Longju; Johnson, Michael; C Hillier, Andrew; Lu, Meng

    2016-03-01

    Guided-mode resonance (GMR) structures consisting of sub-wavelength periodic gratings are capable of producing narrow-linewidth optical resonances. This paper describes a sol-gel-based imprint lithography method for the fabrication of submicron 1D and 2D GMR structures. This method utilizes a patterned polydimethylsiloxane (PDMS) mold to fabricate the grating coupler and waveguide for a GMR device using a sol-gel thin film in a single step. An organic-inorganic hybrid sol-gel film was selected as the imprint material because of its relatively high refractive index. The optical responses of several sol-gel GMR devices were characterized, and the experimental results were in good agreement with the results of electromagnetic simulations. The influence of processing parameters was investigated in order to determine how finely the spectral response and resonant wavelength of the GMR devices could be tuned. As an example potential application, refractometric sensing experiments were performed using a 1D sol-gel device. The results demonstrated a refractive index sensitivity of 50 nm/refractive index unit. This one-step fabrication process offers a simple, rapid, and low-cost means of fabricating GMR structures. We anticipate that this method can be valuable in the development of various GMR-based devices as it can readily enable the fabrication of complex shapes and allow the doping of optically active materials into sol-gel thin film.

  13. Investigation of optical properties of anthocyanin doped into sol-gel based matrix

    Science.gov (United States)

    Hashim, Hasrina; Abdul Aziz, Nik Mohd Azmi Nik; Isnin, Aishah

    2012-06-01

    Anthocyanin dye was extracted from petal of Hibiscus rosasinensis (Bunga Raya) and doped into sol-gel based matrix to investigate an effect of pH change on its optical properties. Sol-gel matrix based on Vinyl triethoxysilene (VTES) as a precursor was prepared through Sol-gel process at pH 7. The sol was doped with 0.1% of Anthocyanin and the same amount of dye was also dissolved in ethanol as a comparative sample. Hydrochloric Acid, HCl and Tetramethylammonium Hydroxide, TMAH were used to change the pH value by adding them at various concentrations into each sample. The emission spectra and chemical structures of the samples were measured by Spectrofluorometer and Fourier Transform Infrared (FTIR) respectively. When excited at 410 nm, two emission peaks at about 492 and 574 nm were observed for Anthocyanin in acidic environment both in ethanol and VTES sol. In base environment however, only Anthocyanin dissolved in ethanol produced emission peak with a single peak at about 539 nm. The sensitivity of Anthocyanin dye toward pH changes in VTES open a possibility to use it as sensing element in which sol-gel based matrix are known to have higher mechanical strength and thermal stability.

  14. High resolution equilibrium calculations of pedestal and SOL plasma in tokamaks

    Science.gov (United States)

    Medvedev, S. Yu; Martynov, A. A.; Drozdov, V. V.; Ivanov, A. A.; Poshekhonov, Yu Yu

    2017-02-01

    For integrated modeling of equilibrium, stability and dynamics of the divertor tokamak plasma with scrape-off layer (SOL) high resolution equilibrium calculations are needed. A new version of the CAXE equilibrium code computes the tokamak equilibrium on a numerical grid adaptive to magnetic surfaces both in the plasma region with closed flux surfaces and in the SOL region with open magnetic lines. The plasma profiles can be prescribed independently in each region with nested flux surfaces, and realistic SOL profiles with very short pressure drop off length can be accurately treated. The influence of the finite current density in SOL on the connection length is studied. From the point of view of the MHD equilibrium and stability modeling, self-consistent calculations of diverted tokamak configurations with finite current density at the separatrix require taking into account plasma outside the separatrix. Calculated high resolution equilibria provide an input to new versions of the ideal MHD stability codes treating tokamak plasma with SOL. The study of the influence of the pressure gradient profile in the pedestal plasma inside and outside the separatrix on the pedestal height limit set by external kink-ballooning mode stability is presented. Another possible application of the high resolution pedestal and SOL equilibrium code is a coupling to the SOLPS code with a purpose to increase equilibrium accuracy and support self-consistent plasma flow/equilibrium modeling.

  15. [Sol-gel preparation of ultrathin nano-hydroxyapatite coating and its characterization].

    Science.gov (United States)

    Yang, Jianhua; Guo, Linghong; Li, Hui

    2006-10-01

    Present study used dip-coating techniques to fabricate ultrathin nano-HA coating on titanium in organic sol-gel of Ca (NO3)2. 4H2O and PO(CH3)3 and inorganic sol-gel of Ca (NO3)2. 4H2O and (NH4)2HPO4. Scanning electron microscope (SEM) and grazing-incidence X-ray diffraction (XRD) were used to observe the morphology and distribution of crystallite size (D) and lattice strain (epsilon) of ultrathin nano-HA coating. After heated at 400 degrees C, the apatite structure of coatings on titanium began to appear. At heating temperature of 400 degrees C-600 degrees C, the effect of heating temperature on D and epsilon of both coatings was obvious. Precursor types significantly affected the particle diameters of nano-HA coatings, which were 25-40 nm for organic sol-gel and about 100 nm for inorganic sol. The thickness of ultrathin nano-HA coatings was 2.5 microm for organic sol-gel and 5 microm for inorganic sol and morphology of interfaces between coating and titanium was intact and homogenous.

  16. Effects of sol aging on resistive switching behaviors of HfOx resistive memories

    Science.gov (United States)

    Hsu, Chih-Chieh; Sun, Jhen-Kai; Tsao, Che-Chang; Chen, Yu-Ting

    2017-03-01

    This work investigates effects of long-term sol-aging time on sol-gel HfOx resistive random access memories (RRAMs). A nontoxic solvent of ethanol is used to replace toxic 2-methoxyethanol, which is usually used in sol-gel processes. The top electrodes are fabricated by pressing indium balls onto the HfOx surface rather than by using conventional sputtering or evaporation processes. The maximum process temperature is limited to be 100 ℃. Therefore, influences of plasma and high temperature on HfOx film can be avoided. Under this circumstance, effects of sol aging time on the HfOx films can be more clearly studied. The current conduction mechanisms in low and high electric regions of the HfOx RRAM are found to be dominated by Ohmic conduction and trap-filled space charge limited conduction (TF-SCLC), respectively. When the sol aging time increases, the resistive switching characteristic of the HfOx layer becomes unstable and the transition voltage from Ohmic conduction to TF-SCLC is also increased. This suggests that an exceedingly long aging time will give a HfOx film with more defect states. The XPS results are consistent with FTIR analysis and they can further explain the unstable HfOx resistive switching characteristic induced by sol aging.

  17. Sol-gel derived zinc oxide films alloyed with cobalt and aluminium

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, Mamta [Department of Electronic Science, University of Delhi South Campus, Benito Juarez Road, New Delhi 110 021 (India); Mehra, R.M., E-mail: rammehra2003@yahoo.co [Department of Electronic Science, University of Delhi South Campus, Benito Juarez Road, New Delhi 110 021 (India)

    2010-05-03

    ZnO films codoped with 5 at.% Co and 1 at.% Al were prepared by sol-gel technique on corning glass and silicon substrates with precursor sols of different pH values. The pH was varied from 5.4 to 11 by adding varying amounts of monoethanolamine to the sol. Since pH plays an important role in controlling the properties of films, we discuss in detail the effect of pH value on the structural, morphological and optical properties of the grown films. X-ray diffraction and atomic force microscopy images reveal that the size of crystallites increases with pH of the sol. The variation of pH in the reaction system influences the density of homogeneous nucleation and the crystal growth along the c-axis. High quality Co and Al codoped ZnO films annealed at 600 {sup o}C have been obtained using a sol with pH = 9. These sol-gel derived films find their suitability to be used as dilute magnetic semiconductors.

  18. Solar Flare Measurements with STIX and MiSolFA

    CERN Document Server

    Casadei, Diego

    2014-01-01

    Solar flares are the most powerful events in the solar system and the brightest sources of X-rays, often associated with emission of particles reaching the Earth and causing geomagnetic storms, giving problems to communication, airplanes and even black-outs. X-rays emitted by accelerated electrons are the most direct probe of solar flare phenomena. The Micro Solar-Flare Apparatus (MiSolFA) is a proposed compact X-ray detector which will address the two biggest issues in solar flare modeling. Dynamic range limitations prevent simultaneous spectroscopy with a single instrument of all X-ray emitting regions of a flare. In addition, most X-ray observations so far are inconsistent with the high anisotropy predicted by the models usually adopted for solar flares. Operated at the same time as the STIX instrument of the ESA Solar Orbiter mission, at the next solar maximum (2020), they will have the unique opportunity to look at the same flare from two different directions: Solar Orbiter gets very close to the Sun wit...

  19. Characterization of carbon cryogels synthesized by sol-gel polycondensation

    Directory of Open Access Journals (Sweden)

    BILJANA BABIC

    2005-02-01

    Full Text Available Resorcinol-formaldehyde (RF cryogels were synthesized by the sol-gel polycondensation of resorcinol (R with formaldehyde (F and freeze-drying was carried out with t-butanol. Carbon cryogels were obtained by pyrolyzing RF cryogels in an inert atmosphere. Characterization by nitrogen adsorption showed that the carbon cryogels were micro and mesoporous materials with high specific surface areas (SBET ~ 550 m2/g. Cyclic voltammetry experiments at various scan rates (2 to 200 mV s-1 were performed to study the electrical double-layer charging of carbon cryogel electrodes in 0.5 mol dm-3 HClO4 solution. It has been demonstrated that it is possible to sub-divide the total specific capacitance into the mesoporous and the microporous specific capacitance by analyzing the linear dependence of the charge (q on the reciprocal of the square root of the potential scan rate (v-1/2, and the linear dependence of the reciprocal charge (1/q on the square root of the potential scan rate (v-1/2. The specific capacitance was found to be constant over a wide range of sample weight (12.5 to 50.0 mg and a very promising specific capacitance value of 150 F/g, was found for this material operating in an acidic 0.5 mol dm-3 HClO4 solution at room temperature.

  20. Modeling of far SOL plasma transport in NSTX

    Energy Technology Data Exchange (ETDEWEB)

    Sergei Krasheninnikov; Alexander Pigarov

    2005-11-02

    For better understanding and characterization of non-diffusive transport occurring in the NSTX tokamak edge plasma, we performed extensive simulations of NSTX edge plasmas with the multi-fluid two-dimensional UEDGE code by using realistic model for impurity sputtering sources and hybrid model for anomalous cross-field transport. Our cross-field transport model incorporates the effects of non-diffusive intermittent transport by introducing anomalous convective velocities whose spatial profile is adjusted for each ion charge state to match available experimental data. The research in 2002-2005 financial years was focused on the following areas: (i) development of capabilities for UEDGE simulation of NSTX spectroscopy data (i.e., the 3D real-geometry postprocessor UEDGE tools for comparison between UEDGE and experimental data), (ii) simulation of multi-diagnostic data from NSTX with UEDGE, (iii) study of anomalous cross-field convective transport of impurity ions, (iv) analysis of divertor plasma opacity to resonance radiation, and (v) study the effects of ballooning-like anomalous cross-field transport and spherical-torus magnetic configuration on parallel plasma flows in the SOL.

  1. /dopamine films prepared by sol-gel method

    Science.gov (United States)

    Valverde-Aguilar, G.; Prado-Prone, G.; Vergara-Aragón, P.; Garcia-Macedo, J.; Santiago, Patricia; Rendón, Luis

    2014-09-01

    Dopamine was encapsulated into nanoporous amorphous TiO2 matrix by sol-gel method under atmospheric conditions. A second sample was obtained by the addition of the crown-ether 15C5 in this previous sample. Thin films were spin-coated on glass wafers. No heat treatment was employed in both films. All films were characterized using infrared spectroscopy, high resolution transmission electronic microscopy, X-ray diffraction, optical absorption and scanning electronic microscopy. Despite the films prepared with 15C5 were no calcined, a partial crystallization was identified. Anatase and rutile nanoparticles with sizes of 4-5 nm were obtained. Photoconductivity technique was used to determine the charge transport mechanism on these films. Experimental data were fitted with straight lines at darkness and under illumination wavelengths at 320, 400, and 515 nm. It indicates an ohmic behavior. Photovoltaic and photoconductivity parameters were determined from the current density vs. the applied-electrical-field results. Amorphous film has bigger photovoltaic and photoconductive parameters than the partially crystalline film. Results observed in the present investigation prove that the nanoporous TiO2 matrix can protect the dopamine inhibiting its chemical instability. This fact modifies the optical, physical and electrical properties of the film, and is intensified when 15C5 is added.

  2. Feeding by Actinophrys sol (Protista, Heliozoa): 1 light microscopy.

    Science.gov (United States)

    Patterson, D J; Hausmann, K

    1981-01-01

    The feeding behavior of the heliozoon Actinophrys sol was investigated using the ciliate Colpidium colpoda as food. The ciliate is caught by adhesion to the arms of the heliozoon. Within 20 min the prey is enclosed by a funnel-shaped pseudopodium which progresses over the prey by the action of its differentiated leading edge. Independent Actinophrys cells may fuse together during prey capture and the early stages of prey digestion. After prey ingestion, the ciliate is lysed and the contents of the food vacuole coagulate. Much of the fluid is removed from the food vacuole and, within 4 h of feeding, the food vacuole has condensed around its coagulated contents. As food vacuole condensation occurs, the peripheral region of the heliozoon cell becomes vacuolated. The appearance of the cell and of the food vacuole remain the same for about 12 h, after which time the undigested residues in the food vacuoles are egested, fused masses of cells separate as uninucleate cells and nuclear division may occur. During feeding, the extrusomes are greatly depleted. These bodies are implicated in the processes of food capture and in the production of food vacuole membrane.

  3. Processing, properties, and applications of sol-gel silica optics

    Science.gov (United States)

    Nogues, Jean-Luc R.; LaPaglia, Anthony J.

    1989-12-01

    For many years the market share maintained by U.S. optics manufacturers has been declining continuously caused in part by intense competition principally from countries in the Far East, and in part by the lack of a highly trained cadre of opticians to replace the current generation. This fact could place in jeopardy the defense system of the United States in case of international war. For example, in 1987, optical glass component imports accounted for approximately 50 percent of the Department of Defense (DOD) consumption. GELTECH's sol-gel technology is a new process for making a high quality optical glass and components for commercial and military uses. This technology offers in addition to being a local source of optics, the possibility to create new materials for high-tech optical applications, and the elimination of the major part of grinding and polishing for which the skill moved off-shore. This paper presents a summary of the solgel technology for the manufacture of high quality optical glass and components. Properties of pure silica glass made by solgel process (Type V and Type VI silicas) are given and include: ultraviolet, visible and near infrared spectrophotometry, optical homogeneity and thermal expansion. Many applications such as near net shape casting or Fresnel lens surface replication are discussed. Several potential new applications offered by the solgel technology such as organic-inorganic composites for non linear optics or scintillation detection are also reported in this paper.

  4. Preparation of silica by sol-gel method using formamide

    Directory of Open Access Journals (Sweden)

    R.F.S. Lenza

    2001-07-01

    Full Text Available In this work we obtained microporous and mesoporous silica gels by sol-gel processing. Tetraethylortosilicate (TEOS was used as precursor. Nitric acid and hydrofluoric acid were used as catalysts. In order to study the affect of formamide as drying additive, we used a molar ratio alkoxide/formamide of 1/1. The performance of formamide in obtaining crack-free gels was evaluated through monolithicity measurements. The structural evolution occurring in the interconnected network of the gels during thermal treatment was monitored by Fourier transform infrared spectroscopy (FTIR, shrinkage and density measurements and nitrogen gas sorption. We noted that in the presence of formamide, the Si-O-Si bonds are stronger and belong to a more cross-linked structure. The samples obtained in the presence of formamide have larger pore volume and its pore structure is in the range of mesoporosity. The samples obtained without additive are microporous. Formamide allowed the preparation of crack-free silica gels stabilized at high temperatures.

  5. Synthesis of Titania-Silica Materials by Sol-Gel

    Directory of Open Access Journals (Sweden)

    Rubia F. S. Lenza

    2002-10-01

    Full Text Available In this work TiO2-SiO2 glasses containing as much as 20 mol % of TiO2 were prepared via sol-gel process using titanium and silicon alkoxides, in the presence of chlorine, in the form of titanium tetrachloride or HCl. The gels were heat-treated until 800 °C. X-ray diffraction and Fourier transform infrared spectroscopy were used to understand the structural properties of TiO2-SiO2 oxides calcined at different temperatures and to evaluate the homogeneity of these materials. The degree of the compactness of the silica network is inferred from the frequency of the asymmetric stretching vibrations of Si-O-Si bonds. Formation of Si-O-Ti bridges, as monitored by the intensity of characteristic 945 cm-1 ¾ 960 cm-1 vibration, is particularly prominent if the method of basic two-step prehydrolysis of silicon alkoxide, addition of titanium alkoxide and completion of hydrolysis was used.

  6. Sol-gel derived electrode materials for supercapacitor applications

    Science.gov (United States)

    Lin, Chuan

    1998-12-01

    Electrochemical capacitors have been receiving increasing interest in recent years for use in energy storage systems because of their high energy and power density and long cycle lifes. Possible applications of electrochemical capacitors include high power pulsed lasers, hybrid power system for electric vehicles, etc. In this dissertation, the preparation of electrode materials for use as electrochemical capacitors has been studied using the sol-gel process. The high surface area electrode materials explored in this work include a synthetic carbon xerogel for use in a double-layer capacitor, a cobalt oxide xerogel for use in a pseudocapacitor, and a carbon-ruthenium xerogel composite, which utilizes both double-layer and faradaic capacitances. The preparation conditions of these materials were investigated in detail to maximize the surface area and optimize the pore size so that more energy could be stored while minimizing mass transfer limitations. The microstructures of the materials were also correlated with their performance as electrochemical capacitors to improve their energy and power densities. Finally, an idealistic mathematical model, including both double-layer and faradaic processes, was developed and solved numerically. This model can be used to perform the parametric studies of an electrochemical capacitor so as to gain a better understanding of how the capacitor works and also how to improve cell operations and electrode materials design.

  7. After Attempted Sample Delivery on Sol 60, False Color

    Science.gov (United States)

    2008-01-01

    This view from the Surface Stereo Imager on NASA's Phoenix Mars Lander on the mission's 60th Martian day, or sol, (July 26, 2008) was taken after the lander's scoop sprinkled a soil sample over Thermal and Evolved-Gas Analyzer (TEGA). The upper part of the picture shows the robotic arm scoop parked open-face down above the TEGA after delivery. The TEGA doors farthest to the right were open to receive the sample into one of TEGA's eight ovens. Not enough material reached the oven to allow an analysis to begin. Some of the soil sample can be seen at the bottom of the adjacent pair of doors. This view is presented in false color, which makes the reddish color of the soil-sample material easy to see. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  8. Mesoporous nanocomposite coatings for photonic devices: sol-gel approach

    Science.gov (United States)

    Islam, Shumaila; Bidin, Noriah; Riaz, Saira; Suan, Lau Pik; Naseem, Shahzad; Sanagi, Mohd. Marsin

    2016-10-01

    Thermally stable, optically active inorganic nanocomposites, i.e., aluminum-silicate (AS) and silica-titania (ST), are synthesized via acid-catalyzed low-temperature sol-gel method in order to get stable, crack-free coating material for photonic devices. The samples are characterized by atomic force microscope, field emission scanning electron microscope (FE-SEM), energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Brunauer-Emmett--Teller (BET) surface area, Barrett-Joyner-Halenda (BJH) pore size distribution surface analysis and UV-Vis spectroscopy. Microscopic results show good incorporation of ST and AS particles as composites with grain size within range of 12-17 and 62-109 nm, respectively. EDX analysis substantiated the stoichiometric formation of homogeneous nanocomposites. XRD of the films reveals primary polycrystalline anatase titania phase and mullite phase of ST and AS nanocomposites. FTIR confirms the heterogeneous bond linkage between titania, silica and alumina species. Furthermore, the fabricated samples have mesoporous nature with high surface area, large pore volume and diameter. The tunable refractive index of 1.33-1.35 with high transparency is obtained for synthesized nanocomposites. The experimental findings show that these physically modified and thermally stable alumina- and titania-doped silica-based composite coatings are promising for photonic devices modification.

  9. Hybrid silica-PVA nanofibers via sol-gel electrospinning.

    Science.gov (United States)

    Pirzada, Tahira; Arvidson, Sara A; Saquing, Carl D; Shah, S Sakhawat; Khan, Saad A

    2012-04-03

    We report on the synthesis of poly(vinyl alcohol) (PVA)-silica hybrid nanofibers via sol-gel electrospinning. Silica is synthesized through acid catalysis of a silica precursor (tetraethyl orthosilicate (TEOS) in ethanol-water), and fibers are obtained by electrospinning a mixture of the silica precursor solution and aqueous PVA. A systematic investigation on how the amount of TEOS, the silica-PVA ratio, the aging time of the silica precursor mixture, and the solution rheology influence the fiber morphology is undertaken and reveals a composition window in which defect-free hybrid nanofibers with diameters as small as 150 nm are obtained. When soaked overnight in water, the hybrid fibers remain intact, essentially maintaining their morphology, even though PVA is soluble in water. We believe that mixing of the silica precursor and PVA in solution initiates the participation of the silica precursor in cross-linking of PVA so that its -OH group becomes unavailable for hydrogen bonding with water. FTIR analysis of the hybrids confirms the disappearance of the -OH peak typically shown by PVA, while formation of a bond between PVA and silica is indicated by the Si-O-C peak in the spectra of all the hybrids. The ability to form cross-linked nanofibers of PVA using thermally stable and relatively inert silica could broaden the scope of use of these materials in various technologies.

  10. "Non-hydrolytic" sol-gel synthesis of molybdenum sulfides

    Science.gov (United States)

    Leidich, Saskia; Buechele, Dominique; Lauenstein, Raphael; Kluenker, Martin; Lind, Cora

    2016-10-01

    Non-hydrolytic sol-gel reactions provide a low temperature solution based synthetic approach to solid-state materials. In this paper, reactions between molybdenum chloride and hexamethyldisilthiane in chloroform were explored, which gave access to both MoS2 and Mo2S3 after heat treatment of as-recovered amorphous samples to 600-1000 °C. Interesting morphologies were obtained for MoS2, ranging from fused spherical particles to well-defined nanoplatelets and nanoflakes. Both 2H- and 3R-MoS2 were observed, which formed thin hexagonal and triangular platelets, respectively. The platelets exhibited thicknesses of 10-30 nm, which corresponds to 15-50 MoS2 layers. No attempts to prevent agglomeration were made, however, well separated platelets were observed for many samples. Heating at 1000 °C led to formation of Mo2S3 for samples that showed well-defined MoS2 at lower temperatures, while less crystalline samples had a tendency to retain the MoS2 structure.

  11. Functionalization of ceramic tile surface by sol-gel technique.

    Science.gov (United States)

    Bondioli, F; Taurino, R; Ferrari, A M

    2009-06-15

    The aim of this investigation was the surface functionalization of industrial ceramic tiles by sol-gel technique to improve at the same time the cleanability of unglazed surfaces. This objective was pursued through the design and preparation of nanostructured coating that was deposited on polished unglazed tiles by air-brushing. In particular TiO(2)-SiO(2) binary film with 1, 2 or 5wt% of titania were prepared by using tetraethoxysilane and titania nanoparticles as precursors. The obtained films were characterized by scratch tests to verify the adhesion of the coatings to the polished tiles. To mainly evaluate the effect of the thermal treatment (temperature range 100-600 degrees C) on the photocatalicity of the coatings, the films were studied under UV exposure by contact angle measurements and cleanability test. Particular attention has been paid to preserve the aesthetical aspect of the final product and the obtained hue variation was evaluated by means of UV-visible spectroscopy and colorimetric analysis.

  12. Infrared Spectroscopy Studies on sol-gel prepared alumina Powders

    Directory of Open Access Journals (Sweden)

    Majid JAFAR TAFRESHI

    2015-03-01

    Full Text Available Gamma-alumina fine particles were synthesized by sol-gel process. Aluminum tri-sec-butoxide (ATB, anhydrous ethyl alcohol (EtOH, water (H2O and hydrochloric acid (HCl were used as starting materials. Different samples were synthesized with EtOH/ATB=60/1, HCl/ATB=0.08/1 and H2O/ATB=1/1 ratios and calcined at different temperatures. Molar ratios of H2O/ATB (from 1 to 25 and HCl/ATB (from 0.08 to 0.4 were changed for some other samples, during synthesizing process. The products were characterized by both XRD and FTIR measurements. Studies were carried out on the effect of calcination temperature and change of H2O/ATB and HCl/ATB ratios on structure and processes involved in phase transformations.DOI: http://dx.doi.org/10.5755/j01.ms.21.1.4872

  13. Mechanisms of silk fibroin sol-gel transitions.

    Science.gov (United States)

    Matsumoto, Akira; Chen, Jingsong; Collette, Adam L; Kim, Ung-Jin; Altman, Gregory H; Cebe, Peggy; Kaplan, David L

    2006-11-01

    Silk fibroin sol-gel transitions were studied by monitoring the process under various physicochemical conditions with optical spectroscopy at 550 nm. The secondary structural change of the fibroin from a disordered state in solution to a beta-sheet-rich conformation in the gel state was assessed by FTIR and CD over a range of fibroin concentrations, temperatures, and pH values. The structural changes were correlated to the degree of gelation based on changes in optical density at 550 nm. No detectable changes in the protein secondary structure (FTIR, CD) were found up to about 15% gelation (at 550 nm), indicating that these early stages of gelation are not accompanied by the formation of beta-sheets. Above 15%, the fraction of beta-sheet linearly increased with the degree of gelation. A pH dependency of gelation time was found with correlation to the predominant acidic side chains in the silk. Electrostatic interactions were related to the rate of gelation above neutral pH. The overall independencies of processing parameters including concentration, temperature, and pH on gel formation and protein structure can be related to primary sequence-specific features in the molecular organization of the fibroin protein. These findings clarify aspects of the self-assembly of this unique family of proteins as a route to gain control of material properties, as well as for new insight into the design of synthetic silk-biomimetic polymers with predictable solution and assembly properties.

  14. Sol-Gel Synthesis and Characterization of Nanoparticles

    Directory of Open Access Journals (Sweden)

    S. Ramesh

    2013-01-01

    Full Text Available The nanoparticles have been synthesized by sol-gel technique. X-ray diffraction, scanning electron microscopy, optical absorption spectroscopy, and electron paramagnetic resonance spectroscopy were used to characterize the sample. The X-ray diffraction results indicate the formation of nanocrystalline materials in tetragonal lattice with P42/nnm space group. The identical distribution of elements were confirmed by scanning electron microscopy with energy dispersive X-ray spectrometry and X-ray mapping. Electron paramagnetic resonance lineshapes of the samples are obtained at various (13 K, 77 K, and 300 K temperatures. The isotropic lineshapes of the sample B1 are attributed to dipole-dipole interaction of Ti3+ ions. The incorporation of Al3+ ions into the sample B2–B5 the isotropic nature of the lineshapes are collapsed due to the distraction in crystal field. Optical absorption spectra results reveal the presence of Ag-TiO2 nanoparticles.

  15. FOURNIER'S GANGRENE COMPLICATING VASECTOMY V.M. ...

    African Journals Online (AJOL)

    hi-tech

    2003-09-09

    Sep 9, 2003 ... The possible operational factors for the complications are explored and preventive ..... trauma, malignancy, malnutrition, renal failure, cortisone therapy, lupus ... second one depended on exogenous testosterone for "normal".

  16. Thermodynamic analysis of sol-gel transition of gelatin in terms of water activity in various solutions.

    Science.gov (United States)

    Miyawaki, Osato; Omote, Chiaki; Matsuhira, Keiko

    2015-12-01

    Sol-gel transition of gelatin was analyzed as a multisite stoichiometric reaction of a gelatin molecule with water and solute molecules. The equilibrium sol-gel transition temperature, Tt , was estimated from the average of gelation and melting temperature measured by differential scanning calorimetry. From Tt and the melting enthalpy, ΔHsol , the equilibrium sol-to-gel ratio was estimated by the van't Hoff equation. The reciprocal form of the Wyman-Tanford equation, which describes the sol-to-gel ratio as a function of water activity, was successfully applied to obtain a good linear relationship. From this analysis, the role of water activity on the sol-gel transition of gelatin was clearly explained and the contributions of hydration and solute binding to gelatin molecules were separately discussed in sol-gel transition. The general solution for the free energy for gel-stabilization in various solutions was obtained as a simple function of solute concentration.

  17. A New Method to Study the Sol-gel Transition Process of Organic/Inorganic Hybrid Materials

    Institute of Scientific and Technical Information of China (English)

    GUO Bin; GAO Jian-gang; CHEN Da-zhu; LIU Jian-ping; HE Ping-sheng; ZHANG Qi-jin

    2005-01-01

    The sol-gel transition process of PMMA/SiO2 hybrid materials was first studied by means of the dynamic torsional vibration method. The different stages of the transition can be described by the change of torque. The temperature-dependent measurement of the gel time(tg) gives the possibility to determine the apparent activation energy(Ea) of this transition according to Flory′s gelation theory. The non-equilibrium thermodynamic fluctuation theory was used to predict the transition behavior. The isothermal transition experiments on hybrid sols with different TEOS(tetraethyl orthosilicate) contents were carried out. The results show that the Ea of a hybrid sol is higher than that of a non- hybrid sol of a TEOS-water-ethanol system. The increasing of TEOS content in a hybrid sol has no obvious effect on the Ea value, but it can enhance the sol-gel reaction rate.

  18. In situ gelation properties of a collagen-genipin sol with a potential for the treatment of gastrointestinal ulcers.

    Science.gov (United States)

    Narita, Takefumi; Yunoki, Shunji; Ohyabu, Yoshimi; Yahagi, Naohisa; Uraoka, Toshio

    2016-01-01

    We investigated the potential of collagen-genipin sols as biomaterials for treating artificial ulcers following endoscopic submucosal dissection. Collagen sol viscosity increased with condensation, allowing retention on tilted ulcers before gelation and resulting in collagen gel deposition on whole ulcers. The 1.44% collagen sols containing genipin as a crosslinker retained sol fluidity at 23°C for >20 min, facilitating endoscopic use. Collagen sols formed gel depositions on artificial ulcers in response to body temperature, and high temperature responsiveness of gelation because of increased neutral phosphate buffer concentration allowed for thick gel deposition on tilted ulcers. Finally, histological observations showed infiltration of gels into submucosal layers. Taken together, the present data show that genipin-induced crosslinking significantly improves the mechanical properties of collagen gels even at low genipin concentrations of 0.2-1 mM, warranting the use of in situ gelling collagen-genipin sols for endoscopic treatments of gastrointestinal ulcers.

  19. Silica- and germania-based dual-ligand sol-gel organic-inorganic hybrid sorbents combining superhydrophobicity and π-π interaction. The role of inorganic substrate in sol-gel capillary microextraction.

    Science.gov (United States)

    Seyyal, Emre; Malik, Abdul

    2017-04-29

    Principles of sol-gel chemistry were utilized to create silica- and germania-based dual-ligand surface-bonded sol-gel coatings providing enhanced performance in capillary microextraction (CME) through a combination of ligand superhydrophobicity and π-π interaction. These organic-inorganic hybrid coatings were prepared using sol-gel precursors with bonded perfluorododecyl (PF-C12) and phenethyl (PhE) ligands. Here, the ability of the PF-C12 ligand to provide enhanced hydrophobic interaction was advantageously combined with π-π interaction capability of the PhE moiety to attain the desired sorbent performance in CME. The effect of the inorganic sorbent component on microextraction performance of was explored by comparing microextraction characteristics of silica- and germania-based sol-gel sorbents. The germania-based dual-ligand sol-gel sorbent demonstrated superior CME performance compared to its silica-based counterpart. Thermogravimetric analysis (TGA) of the created silica- and germania-based dual-ligand sol-gel sorbents suggested higher carbon loading on the germania-based sorbent. This might be indicative of more effective condensation of the organic ligand-bearing sol-gel-active chemical species to the germania-based sol-gel network (than to its silica-based counterpart) evolving in the sol solution. The type and concentration of the organic ligands were varied in the sol-gel sorbents to fine-tune extraction selectivity toward different classes of analytes. Specific extraction (SE) values were used for an objective comparison of the prepared sol-gel CME sorbents. The sorbents with higher content of PF-C12 showed remarkable affinity for aliphatic hydrocarbons. Compared to their single-ligand sol-gel counterparts, the dual-ligand sol-gel coatings demonstrated significantly superior CME performance in the extraction of alkylbenzenes, providing up to ∼65.0% higher SE values. The prepared sol-gel CME coatings provided low ng L(-1) limit of detections (LOD

  20. Application of Sol Self-Clean Bonded Al2O3-SiC-C Castable for Iron Runner

    Institute of Scientific and Technical Information of China (English)

    XU Guotao; ZHANG Honglei; CHEN Huasheng; WANG Yue; LI Huaiyuan; XIONG Yafei

    2006-01-01

    The properties and microstructure of sol self-clean bonded Al2O3-SiC-C castable in iron runner were studied, and the relation between the amount of sol selfclean binder and the properties of castable were discussed. It is believed that the addition of sol self-clean binder can improve the compressive strength, but has little effect on the bulk density and the apparent porosity,which enable the castable to be applicable in different conditions.

  1. Modeling of carbon transport in the divertor and SOL of DIII-D during high performance plasma operation

    Science.gov (United States)

    West, W. P.; Porter, G. D.; Evans, T. E.; Stangeby, P.; Brooks, N. H.; Fenstermacher, M. E.; Isler, R. C.; Rognlien, T. D.; Wade, M. R.; Whyte, D. G.; Wolf, N. S.

    2001-03-01

    The UEDGE modeling code has been used to study the effect of varying the carbon yield from the plasma facing surfaces on the core plasma carbon contamination in DIII-D. The model of the lower single-null, ELMing H-mode plasma shows a remarkably weak dependence of the core carbon concentration over an approximate factor of two variation in the source. This weak dependence is in agreement with the analysis of spectroscopic data from DIII-D [1]. Examination of the carbon transport shows a general flow pattern of carbon as follows: (1) parallel flow from the divertors to the near scrape off layer (SOL) near the separatrix, (2) cross field diffusion from the near SOL to the far SOL (near the wall), and (3) parallel flow from the far SOL to the far region of the inner divertor. The carbon flux from the divertors to the near SOL drops as the sputtering rate is reduced. In the far SOL, background plasma parameters adjust in small ways to produce an increasing carbon density with decreasing sputtering yield. This increasing density of carbon in the far SOL is consistent with a reduction in the parallel velocity of carbon ions flowing from the far SOL back to the inner divertor. Since the carbon density near the separatrix is constant as the sputtering yield is reduced, the increasing density in the far SOL reduces the radial gradient and therefore the diffusive radial flow. A balance in the outward radial diffusive flow from the near SOL and the flow from the divertor into the near SOL maintains the carbon density in the near SOL nearly constant, even though the carbon throughput changes.

  2. Entrapment of subtilisin in ceramic sol-gel coating for antifouling applications.

    Science.gov (United States)

    Regina, Viduthalai Rasheedkhan; Søhoel, Helmer; Lokanathan, Arcot Raghupathi; Bischoff, Claus; Kingshott, Peter; Revsbech, Niels Peter; Meyer, Rikke Louise

    2012-11-01

    Enzymes with antifouling properties are of great interest in developing nontoxic antifouling coatings. A bottleneck in developing enzyme-based antifouling coatings is to immobilize the enzyme in a suitable coating matrix without compromising its activity and stability. Entrapment of enzymes in ceramics using the sol-gel method is known to have several advantages over other immobilization methods. The sol-gel method can be used to make robust coatings, and the aim of this study was to explore if sol-gel technology can be used to develop robust coatings harboring active enzymes for antifouling applications. We successfully entrapped a protease, subtilisin (Savinase, Novozymes), in a ceramic coating using a sol-gel method. The sol-gel formulation, when coated on a stainless steel surface, adhered strongly and cured at room temperature in less than 8 h. The resultant coating was smoother and less hydrophobic than stainless steel. Changes in the coating's surface structure, thickness and chemistry indicate that the coating undergoes gradual erosion in aqueous medium, which results in release of subtilisin. Subtilisin activity in the coating increased initially, and then gradually decreased. After 9 months, 13% of the initial enzyme activity remained. Compared to stainless steel, the sol-gel-coated surfaces with active subtilisin were able to reduce bacterial attachment of both Gram positive and Gram negative bacteria by 2 orders of magnitude. Together, our results demonstrate that the sol-gel method is a promising coating technology for entrapping active enzymes, presenting an interesting avenue for enzyme-based antifouling solutions.

  3. Sol-gel preparation of silica and titania thin films

    Science.gov (United States)

    Thoř, Tomáš; Václavík, Jan

    2016-11-01

    Thin films of silicon dioxide (SiO2) and titanium dioxide (TiO2) for application in precision optics prepared via the solgel route are being investigated in this paper. The sol-gel process presents a low cost approach, which is capable of tailoring thin films of various materials in optical grade quality. Both SiO2 and TiO2 are materials well known for their application in the field of anti-reflective and also highly reflective optical coatings. For precision optics purposes, thickness control and high quality of such coatings are of utmost importance. In this work, thin films were deposited on microscope glass slides substrates using the dip-coating technique from a solution based on alkoxide precursors of tetraethyl orthosilicate (TEOS) and titanium isopropoxide (TIP) for SiO2 and TiO2, respectively. As-deposited films were studied using spectroscopic ellipsometry to determine their thickness and refractive index. Using a semi-empirical equation, a relationship between the coating speed and the heat-treated film thickness was described for both SiO2 and TiO2 thin films. This allows us to control the final heat-treated thin film thickness by simply adjusting the coating speed. Furthermore, films' surface was studied using the white-light interferometry. As-prepared films exhibited low surface roughness with the area roughness parameter Sq being on average of 0.799 nm and 0.33 nm for SiO2 and TiO2, respectively.

  4. First results of NSTX-U SOL reflectometer

    Science.gov (United States)

    Lau, Cornwall; Caughman, John; Hosea, Joel; Perkins, Rory; Taylor, Gary; Wilgen, John

    2016-10-01

    The goal of the Oak Ridge National Laboratory (ORNL) scrape-off-layer (SOL) reflectometer is to measure the density profiles and fluctuations in front of the HHFW antenna on NSTX-U to help understand plasma-antenna coupling and RF-edge interactions, such as density profile modifications due to field-aligned power losses and/or parametric decay instabilities. Originally designed for NSTX parameters, the reflectometer has been upgraded to operate at the increased magnetic fields of NSTX-U by using a combination of O-mode cutoffs, and X-mode L and R cutoffs instead of only X-mode R-cutoff. The use of the X-mode L-cutoff, in particular, is necessary to achieve density profile measurements at the expected full magnetic field capability of NSTX-U. Reflectometer electronics and digitization systems were also upgraded to take measurements with a 20 μs time resolution, so as to reduce the effects of turbulence on the density profile measurement. The first results of these reflectometry measurements on NSTX-U will be shown for a range of plasma conditions. Demonstration that the reflectometer can measure the different cutoffs will also be shown. This work was supported at Oak Ridge National Laboratory, managed by UT-Battelle, LLC, for the U.S. Department of Energy under Contract No. DE-AC05-00OR22725, and at the Princeton Plasma Physics Laboratory under DOE Contract No. DE-AC02-09CH11466.

  5. Synthesis and Characterization of Sol-Gel Prepared Silver Nanoparticles

    Science.gov (United States)

    Ahlawat, Dharamvir Singh; Kumari, Rekha; Rachna; Yadav, Indu

    2014-03-01

    Silver nanoparticles (SNPs) have been successfully prepared using sol-gel method by annealing the sample at 550°C for 30 min. The SNPs were not confirmed by X-ray diffraction (XRD) analysis when the annealing temperature was considered at 450°C. They were also not confirmed without calcination of the sample. The physical mechanism of silver clusters formation in the densified silica matrix with respect to thermal treatment has been understood. The presence of silver metal in the silica matrix was confirmed by XRD analysis and TEM image of the samples. The average size of nanoparticles dispersed in silica matrix was determined as 10.2 nm by the XRD technique. The synthesized nanocomposites were also characterized by UV-Visible spectroscopy with a peak in the absorption spectra at around 375 nm. The distribution of particle size has been reported here in the range from 8 nm to 25 nm by TEM observations of the sample prepared at 550°C. The spherically smaller size (≈10 nm) SNPs have reported the surface plasmons resonance (SPR) peak less than or near to 400 nm due to blue-shifting and effect of local refractive index. Without annealing the silica samples the absorption spectra does not show any peak around 375 nm. The FTIR spectroscopy of the three types of samples prepared at different temperatures (room temperature, 450°C and 550°C) has also been reported. This spectra have provided the identification of different chemical groups in the prepared samples. It has been predicted that the size of SNPs by XRD, UV-Visible and TEM results have agreed well with each other. It may be concluded that formation of SNPs is a function of annealing temperature.

  6. Sol concentration effect on ZnO nanofibers photocatalytic activity synthesized by sol–gel dip coating method

    Science.gov (United States)

    Toubane, M.; Tala-Ighil, R.; Bensouici, F.; Bououdina, M.; Souier, M.; Liu, S.; Cai, W.; Iratni, A.

    2017-03-01

    ZnO thin films were deposited onto glass substrate by sol–gel dip coating method. The initial sol concentrations were varied from 0.2 to 0.5 M. Zinc acetate dihydrate, ethanol and Diethanolamine (DEA) were used as staring material, solvent and stabilizer respectively. The evolution of structural, optical properties and methylene blue (MB) photodegradation of the as-deposited films on sol concentration was investigated. Rietveld refinements of x-ray patterns reveal that all the as-prepared thin films have a Zincite-type structure with grain orientation along to c-axis. The strongest sol concentration is favorable for the highest crystallization quality. However, the high preferred orientation factor (POF) occurs for 0.3 M sol concentration. The field emission scanning electron microscopy observations reveals nanofibrous morphology with different lengths. The nanofibers density increases with increasing sols concentrations until forming a flower-like morphology. The EDS analysis confirms the high purity of the as-deposited ZnO films. It is found that all films present good transparency greater than 95% in the visible range; the optical band gap is slightly reduced with the increase in sol concentration. The photocatalytic degradation is enhanced by 90% with the sol concentration. The K app rate reaction increased with increasing sol concentration. The films stability is found to slightly decrease after the third cycle, especially for 0.5 M sol concentration.

  7. Investigation on the polymorphism of Parkin gene V/L380 in Uygur patients with Parkinson disease in%新疆维吾尔族帕金森病患者Parkin基因V/L380多态性研究

    Institute of Scientific and Technical Information of China (English)

    梁晨; 杨新玲; 彭颜晖; 马青平

    2011-01-01

    Objective To investigate the polymorphism of Parkin gene V/L380 in Uygur patients with Parkinson disease (PD) in Xinjiang. Methods The genetic DNA was extracted from 56 Uygur PD patients (PD group) and 82 Uygur healthy controls (normal control group). The exon 10 of Parkin gene was amplified by PCR. Then the restriction endonuclease method was used to detect the genotype and allele frequency of Parkin gene V/L38O. And the results were compared between the two groups. Results The V/L380 CC genotype of Parkin gene was not found out in PD group and normal control group. The rate of Parkin gene V/L380 GG genotype (78. 6% ) and GC genotype (23. 2% ) , and frequency of G allele (89. 3% ) and C allele (10. 7% ) in PD group were compared with which in normal control group (91.5% , 8.5% ; 95. 7% , 4. 3% ) , and the differences between the two groups were statistical significant (all P <0. 05). Conclusion The polymorphism of Parkin gene V/L38O may be associated with genetic susceptibility of Uygur patients with PD in Xinjiang.%目的 研究新疆维吾尔族帕金森病(PD)患者Parkin基因V/L380位点的多态性.方法 提取56例维吾尔族原发性PD患者(PD组)和82例维吾尔族健康对照者(正常对照组)的基因组DNA,采用PCR扩增所需Parkin基因第10外显子基因片段,用限制性内切酶酶切技术检测其Parkin基因V/L380位点的基因型和等位基因频率,并对两组结果进行比较.结果 PD组与正常对照组均未检出Parkin基因V/1380位点CC型.PD组Parkin基因WL380位点GG型比例(78.6%)、GC型比例(23.2%)及G等位基因频率(89.3%)、C等位基因频率(10.7%)与正常对照组(91.5%,8.5%;95.7%,4.3%)比较,差异均有统计学意义(均P<0.05).结论 Parkin基因V/L380多态性可能与新疆维吾尔族PD患者的遗传易感性有关.

  8. Influencia del tiempo de tratamiento de superficie con ácido fluorhídrico de la porcelana VITA VM 13 en la resistencia de unión a cemento de resina frente a fuerzas de tracción: Estudio in vitro Influence of surface treatment time with hydrofluoric acid of VITA VM13 porcelain on tensile bond strength to a luting resin cement: In vitro study

    Directory of Open Access Journals (Sweden)

    JP Guzmán Thoms

    2012-12-01

    Full Text Available Introducción: Los procedimientos restauradores indirectos son comunes en la clínica diaria actual. Se debe tener cuidado especial en la cementación, pues la gran mayoría de los fracasos ocurren en la interfase diente/restauración. Por esto es indispensable un adecuado tratamiento de superficie de la restauración para lograr una adhesión óptima a la superficie dentaria. Materiales y Métodos: Treinta cilindros de porcelana VITA VM 13 con dimensiones de 5 mm de altura y 7 mm de diámetro fueron separadas aleatoriamente en 3 grupos (n=10 de acuerdo con los tratamientos recibidos. Grupo I (control - sin acondicionamiento superficial; Grupo II - grabado con ácido fluorhídrico al 9.6% por 1 minuto; Grupo III - grabado con ácido fluorhídrico al 9.6% por 2 minutos. Estas fueron probadas en cuanto a su resistencia de unión a la tracción en una máquina universal para pruebas (INSTRON modelo 4411, 3M. Los valores, expresados en MPa, fueron analizados estadísticamente a un nivel de significación del 5%, usando el Análisis de la Varianza (ANOVA de un factor. Resultados: En relación con la prueba de resistencia de unión a la tracción, se encontraron los siguientes valores medios para cada grupo: Grupo I (control - x=3.35 MPa; Grupo II - x=4.64 MPa; Grupo III - x=3.80 MPa. Conclusiones: Según los resultados obtenidos, se puede concluir que el tratamiento de superficie con ácido fluorhídrico durante 1 minuto, promueve microrretenciones que aumentan significativamente los valores de resistencia a la tracción, que puede traducirse en un beneficio clínico mayor.Aim: Indirect restorative procedures are common in the current daily practice. Special care must be taken in the cement, as the vast majority of failures occurs at the interface tooth /restoration. Therefore a proper surface treatment of the restoration is essential to achieve optimum adhesion to the tooth surface. Materials and Methods: Thirty porcelain cylinders VITA VM 13 with

  9. GALVANIC CORROSION OF NICKEL ALLOY INCONEL 718 COUPLED WITH VM 80 SS STEEL IN A SIMULATED FORMATION WATER%镍基合金Inconel 718与抗硫油套管钢在模拟气田地层水中的电偶腐蚀

    Institute of Scientific and Technical Information of China (English)

    魏斌; 严密林; 白真权; 冯耀荣

    2007-01-01

    采用电化学方法研究了在模拟罗家寨气田地层水中镍基合金Inconel 718和抗硫管材VM80 SS之间的电偶腐蚀特征和电偶效应.结果表明,Inconel 718和VM80 SS的自腐蚀电位分别为-260 mV和-770 mV,当阴阳极面积比S=0.25,1,4,8时,电偶电位Eg处于-760 mV~-700 mV之间,随S增大,Eg正移,Ig/Aa的初始值、稳态值和平均值均增大;而Ig/Ac的初始值降低,稳态值变化不大.根据混合电位理论计算的VM80SS的电偶腐蚀效应γ随S增大而增大,γ=1.14~4.82.

  10. Synthesis of partial-stabilized cement (PSC) via sol-gel process.

    Science.gov (United States)

    Wang, Wen-Hsi; Lee, Yuan-Ling; Lin, Chun-Pin; Lin, Feng-Huei

    2008-06-15

    The traditional method of preparing partial-stabilized cement (PSC), which is a kind of calcium silicate cement, is through power mixing method. Low reaction efficiency and initial strength limited the application of PSC as a dental root-end filling material. This study provides a one-step sol-gel process for the synthesis of PSC. A complexing ligand is used for tuning down the activity of aluminum sec-butoxide (ASB) in order to avoid possible self-polymerization. After the modification with complex ligand, there is no residue of reactant observed on the analysis of SDT, and bonding between metal atoms is observed in the FTIR spectrum. Each component of PSC is identified using XRD. The hydration product, which is called portlandite, of sol-gel-synthesized PSC is observed after 1 day of hydration, and crystallinity of portlandite increases much faster than that of traditional PSC. The initial strength of sol-gel-synthesized PSC achieves detectable level 24 h earlier than that of traditional PSC; microhardness value of sol-gel-synthesized PSC at 7th day is 2.98 HV, which is much higher than that of traditional PSC (2.05 HV). PSC is successfully synthesized and the initial strength of PSC is improved by this modified sol-gel process.

  11. Wear characteristics of second-phase-reinforced sol-gel corundum abrasives

    Energy Technology Data Exchange (ETDEWEB)

    Mayer, Joachim [Central Facility for Electron Microscopy (GFE), RWTH Aachen University, 52056 Aachen (Germany)]. E-mail: mayer@gfe.rwth-aachen.de; Engelhorn, Robert [Laboratory for Machine Tools and Production Engineering (WZL), RWTH Aachen University, 52056 Aachen (Germany); Bot, Rosemarie [Laboratory for Machine Tools and Production Engineering (WZL), RWTH Aachen University, 52056 Aachen (Germany); Weirich, Thomas [Central Facility for Electron Microscopy (GFE), RWTH Aachen University, 52056 Aachen (Germany); Herwartz, Cleo [Central Facility for Electron Microscopy (GFE), RWTH Aachen University, 52056 Aachen (Germany); Klocke, Fritz [Laboratory for Machine Tools and Production Engineering (WZL), RWTH Aachen University, 52056 Aachen (Germany)

    2006-08-15

    The use of sol-gel technologies makes it possible to manufacture new corundum-based abrasives with superior performance in terms of grinding processes. The aim of the present work is to reveal the detailed wear mechanisms on a nanometre scale and relate them to the particular microstructure of these new materials. A commercial sol-gel corundum (Cubitron 321{sup TM}) was used. In the grinding experiments, wheels consisting of four different mixtures with 0%, 30%, 50% and 100% of sol-gel corundum were used to machine a tool steel (100Cr6V) by plane grinding. Changes to the contact zone were studied after controlled abrasion experiments on hard steel substrates using a pin-on-wheel tribometer, in single grit scratch tests and after tests of resistance to heat shock. Cross-sections through contact areas of a sol-gel grain were prepared using a focused ion beam workstation and investigated using conventional and analytical transmission electron microscopy. The results indicate that the combined effect of controlled propagation of subsurface shear cracks and plastic deformation leads to the formation of flat contact zones. On these contact zones, a nanocrystalline FeO debris layer adheres to the alumina. The results of our investigations were verified in grinding experiments and give insight into the physical reasons of the superior tribological properties of the sol-gel corundum abrasives.

  12. Carbon nanotube-coated solid-phase microextraction metal fiber based on sol-gel technique.

    Science.gov (United States)

    Jiang, Ruifen; Zhu, Fang; Luan, Tiangang; Tong, Yexiang; Liu, Hong; Ouyang, Gangfeng; Pawliszyn, Janusz

    2009-05-29

    A novel carbon nanotube (CNT)-coated solid-phase microextraction fiber was prepared based on sol-gel technique. Commonly used fragile fused silica fiber was replaced with stainless steel wire, which made the fiber unbreakable. An approach was also proposed for batch producing, and good reproducibilities for fiber to fiber and between fibers were achieved. Experiments showed that the sol-gel-CNT fiber exhibited high thermal stability to resist 350 degrees C and excellent solvent durability in methanol and acetonitrile. Compared to commercial polydimethylsiloxane (PDMS) fiber, the sol-gel-CNT fiber represented significantly improved extraction efficiencies for both polar (phenols) and non-polar (benzene, toluene, ethylbenzene, and o-xylene) compounds. Meanwhile, no replacement effect, low carry-over and wide linear range demonstrated that the newly prepared sol-gel-CNT coating has liquid properties, which allow a relatively easy quantification procedure. Moreover, the characterization of the sol-gel-CNT coating was also evaluated with McReynold probe solutes. The results showed that the coating has better affinity for all the five types of solutes compared to commercial 7microm PDMS fiber, which suggested that the coating has the potential to be developed as GC stationary phase.

  13. 3D Monte-Carlo study of toroidally discontinuous limiter SOL configurations of Aditya tokamak

    Science.gov (United States)

    Sahoo, Bibhu Prasad; Sharma, Devendra; Jha, Ratneshwar; Feng, Yühe

    2017-08-01

    The plasma-neutral transport in the scrape-off layer (SOL) region formed by toroidally discontinuous limiters deviates from usual uniform SOL approximations when 3D effects caused by limiter discreteness begin to dominate. In an upgrade version of the Aditya tokamak, originally having a toroidally localized poloidal ring-like limiter, the newer outboard block and inboard belt limiters are expected to have smaller connection lengths and a multiple fold toroidal periodicity. The characteristics of plasma discharges may accordingly vary from the original observations of large diffusivity, and a net improvement and the stability of the discharges are desired. The estimations related to 3D effects in the ring limiter plasma transport are also expected to be modified and are updated by predictive simulations of transport in the new block limiter configuration. A comparison between the ring limiter results and those from new simulations with block limiter SOL shows that for the grids produced using same core plasma equilibrium, the modified SOL plasma flows and flux components have enhanced poloidal periodicity in the block limiter case. These SOL modifications result in a reduced net recycling for the equivalent edge density values. Predictions are also made about the relative level of the diffusive transport and its impact on the factors limiting the operational regime.

  14. Cytotoxicity Property of Nano-TiO2 Sol and Nano-TiO2 Powder

    Directory of Open Access Journals (Sweden)

    Pingting He

    2011-01-01

    Full Text Available A homogeneous and transparent titania (TiO2 sol with nanosized anatase TiO2 particles was prepared by hydrothermal synthesis method. The transmission electron microscope and X-ray diffraction were used to characterize the structure and morphology of particulates in the TiO2 sol and purchased TiO2 powder. The results show that the homogeneous anatase crystalline phase was formed and the size of the spindle-like particle in sol was about 20 nm in width and 150 nm in average length, and the particulates of the purchased powder were globular-like about 50 nm in diameter. In addition, a consistent set of in vitro experimental protocols was used to study the effects of nano-TiO2 sol as prepared and nano-TiO2 powder on mouse peritoneal macrophage. The cytotoxicity tests in vitro indicate that, with the increasing of TiO2 sol concentration contaminated with the cells, the relative proliferation rate of macrophage cells was improved slightly after the cells contaminated for 24 h, but it reduced rapidly after contaminated for 48 h. The purchased nano-TiO2 powder inhibited the growth of the cells obviously as cultivating with macrophage both for 24 h and 48 h.

  15. Dynamics of Methyl Methacrylate Nanoconfined in Silica Sol Glasses Studied by Optical Kerr Effect Spectroscopy

    Science.gov (United States)

    Meng, Dujuan; Xue, Lianjie; Tamas, George; Quitevis, Edward; Simon, Sindee

    2014-03-01

    Nanoconfinement has been found to have an effect on polymerization processes [1,2] and on the glass transition temperature Tg [3]. Here we report studies of the nanoconfinement effect on the dynamics of monomers in the pores of silica sol-gel glass. The samples were prepared under a vacuum and studied by using optical Kerr effect (OKE) spectroscopy. The reorientational dynamics of methyl methacrylate (MMA) confined in silica sol-gel glasses with pore diameters of 32, 41, and 82 Å was studied. The decays of the reorientational correlation function C(t) became longer as the pore size decreased. Based on the analysis of the reorientational correlation functions using a two-state model [4], the nanoconfinement effect is due to the interaction of molecules with the surface of the silica-gel glass. In a study of the effect of nanoconfinement in modified silica sol-gel glasses, which were obtained by refluxing the sol-gel glasses in methanol to give hydrophobic pore surfaces, the decay is faster in the modified silica gel glass than in the unmodified sol-gel glass. This work is supported by NSF Grant CMMI-1235346.

  16. Visible Light Induced Photocatalysis of Cerium Ion Modified Titania Sol and Nanocrystallites

    Institute of Scientific and Technical Information of China (English)

    Yibing XIE; Chunwei YUAN

    2004-01-01

    The cerium ion(Ce4+) doped titania sol and nanocrystallites were prepared by chemical coprecipitation-peptization and hydrothermal synthesis methods, respectively. The X-ray diffraction pattern shows that Ce4+-TiO2 xerogel powder has semicrystalline structure and thermal sintering sample has crystalline structure. Ce4+-TiO2 nanocrystallites are composed of the major anatase phase titania (88.82 wt pct) and a small amount of crystalline cerium titanate.AFM micrograph shows that primary particle size of well-dispersed ultrafine sol particles is below 15 nm in diameter.The particle sizes are 30 nm for xerogel sample and 70 nm for nanocrystallites sample, which is different from the estimated values (2.41 nm and 4.53 nm) by XRD Scherrer's formula. The difference is mainly due to aggregation of nanocrystallites. The experimental results exhibit that photocatalysts of Ce4+-TiO2 sol and nanocrystallites have the ability to photodegrade reactive brilliant red dye (X-3B) under visible light irradiation with the ion-TiO2/VIS/dye system. Moreover, Ce4+ doped titania sol has shown higher efficiency than the nanocrystallites sample in respect of potocatalytic activity. Meanwhile, dye photodegradation mechanisms are proposed to different photocatalytic reaction systems, which are dye photosensitization, ion-dye photosensitization and interband photocatalysis & dye photosensitization with respect to TiO2 nanocrystallites, Ce4+-TiO2 sol and Ce4+-TiO2 nanocrystallites system.

  17. Radiation hardening of sol gel-derived silica fiber preforms through fictive temperature reduction.

    Science.gov (United States)

    Hari Babu, B; Lancry, Matthieu; Ollier, Nadege; El Hamzaoui, Hicham; Bouazaoui, Mohamed; Poumellec, Bertrand

    2016-09-20

    The impact of fictive temperature (Tf) on the evolution of point defects and optical attenuation in non-doped and Er3+-doped sol-gel silica glasses was studied and compared to Suprasil F300 and Infrasil 301 glasses before and after γ-irradiation. To this aim, sol-gel optical fiber preforms have been fabricated by the densification of erbium salt-soaked nanoporous silica xerogels through the polymeric sol-gel technique. These γ-irradiated fiber preforms have been characterized by FTIR, UV-vis-NIR absorption spectroscopy, electron paramagnetic resonance, and photoluminescence measurements. We showed that a decrease in the glass fictive temperature leads to a decrease in the glass disorder and strained bonds. This mainly results in a lower defect generation rate and thus less radiation-induced attenuation in the UV-vis range. Furthermore, it was found that γ-radiation "hardness" is higher in Er3+-doped sol-gel silica compared to un-doped sol-gel silica and standard synthetic silica glasses. The present work demonstrates an effective strategy to improve the radiation resistance of optical fiber preforms and glasses through glass fictive temperature reduction.

  18. The Phenomena of Spreading of Hydrotalcite Sol on A Porous Silica Surface Governed by Marangoni Effect

    Directory of Open Access Journals (Sweden)

    Z. Helwani

    2012-12-01

    Full Text Available Wetting phenomena plays a crucial role in a wide range of technological applications. Spreading of liquids on solids involving phase change is encountered in many areas ranging from biological systems to industrial applications such as coatings, printing, painting and spraying. The fundamental study on wetting of membrane precursors namely hydrotalcite sols on a porous silica surface with different types of precursor material was successfully carried out. Relationship between the contact angle of a hydrotalcite droplet on silica surface and the Marangoni effect was also investigated. The presence of PVA in hydrotalcite sols was found to influence the rheological properties of the sols significantly, resulting in higher viscosity and ultimately leading to lower contact angle on solid surfaces. The degree of hydrotalcite's philicity on a substrate was improved by the addition of PVA solution. In this study, the spreading of a liquid droplet on a solid surface controlled by a surface tension gradient, due to Marangoni effect was found to drive better spreading of the liquid droplet. Marangoni Number, Ma was found to be proportionally related with the surface tension of the sols but inversely proportional to contact angles of the sols. Marangoni forces that decreased the contact angle, promoted spreading of hydrotalcite droplets on the selected glass substrates. Keywords: contact angle, hydrotalcite, marangoni effect, spreading, wetting evolution

  19. EFFECT OF SOL CONCENTRATION AND SUBSTRATE TYPE ON MICROSTRUCTURE FORMATION OF PZT THIN FILMS

    Directory of Open Access Journals (Sweden)

    ĽUBOMÍR MEDVECKÝ

    2011-03-01

    Full Text Available Pb(Zr0.52Ti0.48O3 (PZT sols were prepared by a modified sol-gel route using both solvents - acetic acid and stabilizer solution (n-propanol : 1,2-propanediol in the rate 10 : 1. The sols were deposited by spin-coating onto platinized Al2O3 or SiO2/Si substrates. Results of SEM and XRD analyses confirmed, that the transformation of the amorphous PZT film to perovskite structure happened after sintering at 650°C. The mechanism of microstructure formation has described for morphologicaly different perovskite particle types in 1, 2 and 3-layered PZT thin films with thickness of 200-500 nm on used substrates. Three different PZT film microstructure types in dependence on the applied sol concentration were found. It was found, that the PZT/Pt/Al2O3 film microstructure at 1.0 M sol concentration was composed of two forms of perovskite particles, big rosette and irregular cuboidal particles. Small spherical particles and rosette structure were found in PZT/Pt/Si/SiO2 films.

  20. Preparation and rapid analysis of antibacterial silver, copper and zinc doped sol-gel surfaces.

    Science.gov (United States)

    Jaiswal, Swarna; McHale, Patrick; Duffy, Brendan

    2012-06-01

    The colonisation of clinical and industrial surfaces with microorganisms, including antibiotic-resistant strains, has promoted increased research into the development of effective antibacterial and antifouling coatings. This study describes the preparation of metal nitrate (Ag, Cu, Zn) doped methyltriethoxysilane (MTEOS) coatings and the rapid assessment of their antibacterial activity using polyproylene microtitre plates. Microtitre plate wells were coated with different volumes of liquid sol-gel and cured under various conditions. Curing parameters were analysed by thermogravimetric analysis (TGA) and visual examination. The optimum curing conditions were determined to be 50-70°C using a volume of 200 μl. The coated wells were challenged with Gram-positive and Gram-negative bacterial cultures, including biofilm-forming and antibiotic-resistant strains. The antibacterial activities of the metal doped sol-gel, at equivalent concentrations, were found to have the following order: silver>zinc>copper. The order is due to several factors, including the increased presence of silver nanoparticles at the sol-gel coating surface, as determined by X-ray photoelectron spectroscopy, leading to higher elution rates as measured by inductively coupled plasma atomic emission spectroscopy (ICP-AES). The use of microtitre plates enabled a variety of sol-gel coatings to be screened for their antibacterial activity against a wide range of bacteria in a relatively short time. The broad-spectrum antibacterial activity of the silver doped sol-gel showed its potential for use as a coating for biomaterials.