Conditional transfer of emission rights. Not a good idea

International Nuclear Information System (INIS)

Van Engelen, Th.C.J.A.

2004-01-01

The Dutch government embraces the idea that trading of emission allowances is a useful way of reducing the emission of harmful gasses. In the current plans to amend the Environmental Management Act, however, the legislator has chosen for a system where allowances may only be transferred in accordance with strict conditions. These conditions do not provide a legal framework for an efficient emission allowances trading market. As a result, Dutch industry will potentially be placed in an unfavourable position. The legislator, it is suggested, should opt for fully transferable allowances. It is crucial that an efficient international market for trading in allowances is established. This means that it should be possible to trade these allowances easily, without excessive legal restrictions. The aim of the legislator is to prevent extreme situations in this market. While its concerns are valid, however, the legislator has missed the mark by choosing a system whereby transfer of allowances is subject to excessive conditions. The legal consequence of not fulfilling one or more of the conditions during the sale is that the allowance will not be legally transferred, and the seller will remain the proprietor of the allowance, without either the seller or the buyer being aware of the situation. It is clear that this would be an unworkable situation as it would not be possible from a practical angle to simply and quickly check previous transactions. Overall, this would result in high transactions costs, which in turn would be a barrier to an efficient market. In summary, an efficient market in emission allowances seems to be an illusion if the transfer of allowances are subject to such conditions as are presently envisaged by the law. It is suggested that the legislator can reach its goals by dropping the conditions for transfers and by supervising the transactions through administrative and criminal procedures instead. This will not affect the owners-hip of emission allowances

Ideal heat transfer conditions for tubular solar receivers with different design constraints

Science.gov (United States)

Kim, Jin-Soo; Potter, Daniel; Gardner, Wilson; Too, Yen Chean Soo; Padilla, Ricardo Vasquez

2017-06-01

The optimum heat transfer condition for a tubular type solar receiver was investigated for various receiver pipe size, heat transfer fluid, and design requirement and constraint(s). Heat transfer of a single plain receiver pipe exposed to concentrated solar energy was modelled along the flow path of the heat transfer fluid. Three different working fluids, molten salt, sodium, and supercritical carbon dioxide (sCO2) were considered in the case studies with different design conditions. The optimized ideal heat transfer condition was identified through fast iterative heat transfer calculations solving for all relevant radiation, conduction and convection heat transfers throughout the entire discretized tubular receiver. The ideal condition giving the best performance was obtained by finding the highest acceptable solar energy flux optimally distributed to meet different constraint(s), such as maximum allowable material temperature of receiver, maximum allowable film temperature of heat transfer fluid, and maximum allowable stress of receiver pipe material. The level of fluid side turbulence (represented by pressure drop in this study) was also optimized to give the highest net power production. As the outcome of the study gives information on the most ideal heat transfer condition, it can be used as a useful guideline for optimal design of a real receiver and solar field in a combined manner. The ideal heat transfer condition is especially important for high temperature tubular receivers (e.g. for supplying heat to high efficiency Brayton cycle turbines) where the system design and performance is tightly constrained by the receiver pipe material strength.

Transient heat transfer into superfluid helium under confined conditions

International Nuclear Information System (INIS)

Filippov, Yu.P.; Miklyaev, V.M.; Sergeev, I.A.

1988-01-01

Transient thermal processes at solid-HeII interface at input of step pulse of heat load was investigated. Particular attention is given to the study of influence of geometry of experimental specimen upon the heat transfer dynamics. Abrupt breakdown of highly efficient transfer modes caused by the developmet of superfluid turbulence under confined condition is revealed, and accompanying temperature shift is registered. Some characteristic parameters are selected, their dependence on experimental conditions is established

Match properties of heat transfer and coupled heat and mass transfer processes in air-conditioning system

International Nuclear Information System (INIS)

Zhang Tao; Liu Xiaohua; Zhang Lun; Jiang Yi

2012-01-01

Highlights: ► Investigates match properties of heat or mass transfer processes in HVAC system. ► Losses are caused by limited transfer ability, flow and parameter mismatching. ► Condition of flow matching is the same heat capacity of the fluids. ► Parameter matching is only reached along the saturation line in air–water system. ► Analytical solutions of heat and mass transfer resistance are derived. - Abstract: Sensible heat exchangers and coupled heat and mass transfer devices between humid air and water/desiccant are commonly used devices in air-conditioning systems. This paper focuses on the match properties of sensible heat transfer processes and coupled heat and mass transfer processes in an effort to understand the reasons for performance limitations in order to optimize system performance. Limited heat transfer capability and flow mismatching resulted in heat resistance of the sensible heat transfer process. Losses occurred during the heat and mass transfer processes due to limited transfer capability, flow mismatching, and parameter mismatching. Flow matching was achieved when the heat capacities of the fluids were identical, and parameter matching could only be reached along the saturation line in air–water systems or the iso-concentration line in air–desiccant systems. Analytical solutions of heat transfer resistance and mass transfer resistance were then derived. The heat and mass transfer process close to the saturation line is recommended, and heating sprayed water resulted in better humidification performance than heating inlet air in the air humidifier.

Conditional Income Transfers in Latin America: Palliatives for poverty?

Directory of Open Access Journals (Sweden)

Gepherson Macêdo Espínola

2018-02-01

Full Text Available This text discusses the implementation of conditional income transfer programs in Latin America as a strategy to confront poverty in the region. It synthetically contextualizes Latin American development over time, using statistical data to reveal not only the high levels of poverty, but also educational and health conditions. These programs, as a rule, seek to alleviate and overcome poverty through monetary disbursements and fulfillment of health and educational agendas that, in thesis, increase the human capital of the poor and allow overcoming poverty in the long term. It concludes that despite the benefits for the families, the conditional income transfer programs of Latin America, on their own, are still not capable of confronting the structural poverty that marks the region, and are promoting palliatives for the poor living conditions, without overcoming them.

Surface modification of nanodiamond through metal free atom transfer radical polymerization

Energy Technology Data Exchange (ETDEWEB)

Zeng, Guangjian; Liu, Meiying; Shi, Kexin; Heng, Chunning; Mao, Liucheng; Wan, Qing; Huang, Hongye [Department of Chemistry, Nanchang University, 999 Xuefu Avenue, Nanchang 330031 (China); Deng, Fengjie, E-mail: fengjiedeng@aliyun.com [Department of Chemistry, Nanchang University, 999 Xuefu Avenue, Nanchang 330031 (China); Zhang, Xiaoyong, E-mail: xiaoyongzhang1980@gmail.com [Department of Chemistry, Nanchang University, 999 Xuefu Avenue, Nanchang 330031 (China); Wei, Yen, E-mail: weiyen@tsinghua.edu.cn [Department of Chemistry and the Tsinghua Center for Frontier Polymer Research, Tsinghua University, Beijing, 100084 (China)

2016-12-30

Highlights: • Surface modification of ND with water soluble and biocompatible polymers. • Functionalized ND through metal free surface initiated ATRP. • The metal free surface initiated ATRP is rather simple and effective. • The ND-poly(MPC) showed high dispersibility and desirable biocompatibility. - Abstract: Surface modification of nanodiamond (ND) with poly(2-methacryloyloxyethyl phosphorylcholine) [poly(MPC)] has been achieved by using metal free surface initiated atom transfer radical polymerization (SI-ATRP). The ATRP initiator was first immobilized on the surface of ND through direct esterification reaction between hydroxyl group of ND and 2-bromoisobutyryl bromide. The initiator could be employed to obtain ND-poly(MPC) nanocomposites through SI-ATRP using an organic catalyst. The final functional materials were characterized by {sup 1}H nuclear magnetic resonance, transmission electron microscopy, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy and thermo gravimetric analysis in detailed. All of these characterization results demonstrated that ND-poly(MPC) have been successfully obtained via metal free photo-initiated SI-ATRP. The ND-poly(MPC) nanocomposites shown enhanced dispersibility in various solvents as well as excellent biocompatibility. As compared with traditional ATRP, the metal free ATRP is rather simple and effective. More importantly, this preparation method avoided the negative influence of metal catalysts. Therefore, the method described in this work should be a promising strategy for fabrication of polymeric nanocomposites with great potential for different applications especially in biomedical fields.

Surface modification of nanodiamond through metal free atom transfer radical polymerization

International Nuclear Information System (INIS)

Zeng, Guangjian; Liu, Meiying; Shi, Kexin; Heng, Chunning; Mao, Liucheng; Wan, Qing; Huang, Hongye; Deng, Fengjie; Zhang, Xiaoyong; Wei, Yen

2016-01-01

Highlights: • Surface modification of ND with water soluble and biocompatible polymers. • Functionalized ND through metal free surface initiated ATRP. • The metal free surface initiated ATRP is rather simple and effective. • The ND-poly(MPC) showed high dispersibility and desirable biocompatibility. - Abstract: Surface modification of nanodiamond (ND) with poly(2-methacryloyloxyethyl phosphorylcholine) [poly(MPC)] has been achieved by using metal free surface initiated atom transfer radical polymerization (SI-ATRP). The ATRP initiator was first immobilized on the surface of ND through direct esterification reaction between hydroxyl group of ND and 2-bromoisobutyryl bromide. The initiator could be employed to obtain ND-poly(MPC) nanocomposites through SI-ATRP using an organic catalyst. The final functional materials were characterized by 1 H nuclear magnetic resonance, transmission electron microscopy, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy and thermo gravimetric analysis in detailed. All of these characterization results demonstrated that ND-poly(MPC) have been successfully obtained via metal free photo-initiated SI-ATRP. The ND-poly(MPC) nanocomposites shown enhanced dispersibility in various solvents as well as excellent biocompatibility. As compared with traditional ATRP, the metal free ATRP is rather simple and effective. More importantly, this preparation method avoided the negative influence of metal catalysts. Therefore, the method described in this work should be a promising strategy for fabrication of polymeric nanocomposites with great potential for different applications especially in biomedical fields.

Influence of microscale surface modification on impinging flow heat transfer performance

NARCIS (Netherlands)

Taha, T.J.; Lefferts, Leonardus; van der Meer, Theodorus H.

2016-01-01

An experimental approach has been used to investigate the influence of a thin layer of carbon nanotubes (CNTs) on the convective heat transfer performance under impinging flow conditions. A successful synthesis of CNT layers was achieved using a thermal catalytic vapor deposition process (TCVD) on

Boiling heat transfer and dryout in helically coiled tubes under different pressure conditions

International Nuclear Information System (INIS)

Chung, Young-Jong; Bae, Kyoo-Hwan; Kim, Keung Koo; Lee, Won-Jae

2014-01-01

Highlights: • Heat transfer characteristics and dryout for helically coiled tube are performed. • A boiling heat transfer tends to increase with a pressure increase. • Dryout occurs at high quality test conditions investigated. • Steiner–Taborek’s correlation is predicted well based on the experimental results. - Abstract: A helically coiled once-through steam generator has been used widely during the past several decades for small nuclear power reactors. The heat transfer characteristics and dryout conditions are important to optimal design a helically coiled steam generator. Various experiments with the helically coiled tubes are performed to investigate the heat transfer characteristics and occurrence condition of a dryout. For the investigated experimental conditions, Steiner–Taborek’s correlation is predicted reasonably based on the experimental results. The pressure effect is important for the boiling heat transfer correlation. A boiling heat transfer tends to increase with a pressure increase. However, it is not affected by the pressure change at a low power and low mass flow rate. Dryout occurs at high quality test conditions investigated because a liquid film on the wall exists owing to a centrifugal force of the helical coil

Effect of Reaction Conditions on the Surface Modification of Cellulose Nanofibrils with Aminopropyl Triethoxysilane

Directory of Open Access Journals (Sweden)

Eduardo Robles

2018-04-01

Full Text Available Nine different surface modifications of cellulose nanofibrils (CNF with 3-aminopropyl triethoxysilane (ATS by using three different solvent systems (water, ethanol, and a mixture of both were investigated. The effect of reaction conditions, such as silane to cellulose ratio and solvent type were evaluated to determine their contribution to the extent of the silane modification. Nanofibril properties were evaluated by infrared spectroscopy, powder X-ray diffraction, surface free energy, thermogravimetry, 13C and 29Si nuclear magnetic resonance, and electronic microscopy. The influence of the solvent in the solvolysis of the silane was reflected in the presence or absence of ethoxy groups in the silane. On the other hand, whereas the surface modification was increased directly proportionally to silane ratio on the reaction, the aggregation of nanofibrils was also increased, which can play a negative role in certain applications. The increment of silane modification also had substantial repercussions on the crystallinity of the nanofibrils by the addition of amorphous components to the crystalline unit; moreover, silane surface modifications enhanced the hydrophobic character of the nanofibrils.

Optimizing viral and non-viral gene transfer methods for genetic modification of porcine mesenchymal stem cells

DEFF Research Database (Denmark)

Stiehler, Maik; Duch, Mogens; Mygind, Tina

2006-01-01

INTRODUCTION: Mesenchymal stem cells (MSCs) provide an excellent source of pluripotent progenitor cells for tissue-engineering applications due to their proliferation capacity and differentiation potential. Genetic modification of MSCs with genes encoding tissue-specific growth factors...... viral and non-viral ex vivo gene delivery systems with respect to gene transfer efficiency, maintenance of transgene expression, and safety issues using primary porcine MSCs as target cells. MATERIALS AND METHODS: MSCs were purified from bone marrow aspirates from the proximal tibiae of four 3-month......-old Danish landrace pigs by Ficoll step gradient separation and polystyrene adherence technique. Vectors expressing enhanced green fluorescent protein (eGFP) and human bone morphogenetic protein-2 (BMP-2) were transferred to the cells by different non-viral methods and by use of recombinant adeno...

Experimental determination of the heat transfer coefficient in shell-and-tube condensers using the Wilson plot method

Directory of Open Access Journals (Sweden)

Havlik Jan

2017-01-01

Full Text Available This article deals with the experimental determination of heat transfer coefficients. The calculation of heat transfer coefficients constitutes a crucial issue in design and sizing of heat exchangers. The Wilson plot method and its modifications based on measured experimental data utilization provide an appropriate tool for the analysis of convection heat transfer processes and the determination of convection coefficients in complex cases. A modification of the Wilson plot method for shell-and-tube condensers is proposed. The original Wilson plot method considers a constant value of thermal resistance on the condensation side. The heat transfer coefficient on the cooling side is determined based on the change in thermal resistance for different conditions (fluid velocity and temperature. The modification is based on the validation of the Nusselt theory for calculating the heat transfer coefficient on the condensation side. A change of thermal resistance on the condensation side is expected and the value is part of the calculation. It is possible to improve the determination accuracy of the criterion equation for calculation of the heat transfer coefficient using the proposed modification. The criterion equation proposed by this modification for the tested shell-and-tube condenser achieves good agreement with the experimental results and also with commonly used theoretical methods.

Core-debris quenching-heat-transfer rates under top- and bottom-reflood conditions

International Nuclear Information System (INIS)

Ginsberg, T.; Tutu, N.; Klages, J.; Schwarz, C.E.; Sanborn, Y.

1983-02-01

This paper presents recent experimental data for the quench-heat-transfer characteristics of superheated packed beds of spheres which were cooled, in separate experiments, by top- and bottom-flooding modes. Experiments were carried out with beds of 3-mm steel spheres of 330-mm height. The initial bed temperature was 810 K. The observed heat-transfer rates are strongly dependent on the mode of water injection. The results suggest that top-flood bed quench heat transfer is limited by the rate at which water can penetrate the bed under two-phase countercurrent-flow conditions. With bottom-reflood the heat-transfer rate is an order-of-magnitude greater than under top-flood conditions and appears to be limited by particle-to-fluid film boiling heat transfer

Making Conditional Cash Transfer Programs More Efficient : Designing for Maximum Effect of the Conditionality

OpenAIRE

de Janvry, Alain; Sadoulet, Elisabeth

2006-01-01

Conditional cash transfer programs are now used extensively to encourage poor parents to increase investments in their children's human capital. These programs can be large and expensive, motivating a quest for greater efficiency through increased impact of the programs' imposed conditions on human capital formation. This requires designing the programs' targeting and calibration rules spe...

Geometrical modification transfer between specific meshes of each coupled physical codes. Application to the Jules Horowitz research reactor experimental devices

International Nuclear Information System (INIS)

Duplex, B.

2011-01-01

The CEA develops and uses scientific software, called physical codes, in various physical disciplines to optimize installation and experimentation costs. During a study, several physical phenomena interact, so a code coupling and some data exchanges between different physical codes are required. Each physical code computes on a particular geometry, usually represented by a mesh composed of thousands to millions of elements. This PhD Thesis focuses on the geometrical modification transfer between specific meshes of each coupled physical code. First, it presents a physical code coupling method where deformations are computed by one of these codes. Next, it discusses the establishment of a model, common to different physical codes, grouping all the shared data. Finally, it covers the deformation transfers between meshes of the same geometry or adjacent geometries. Geometrical modifications are discrete data because they are based on a mesh. In order to permit every code to access deformations and to transfer them, a continuous representation is computed. Two functions are developed, one with a global support, and the other with a local support. Both functions combine a simplification method and a radial basis function network. A whole use case is dedicated to the Jules Horowitz reactor. The effect of differential dilatations on experimental device cooling is studied. (author) [fr

Plasma transferred arc surface modification of atmospheric plasma sprayed ceramic coatings

Energy Technology Data Exchange (ETDEWEB)

Ulutan, Mustafa; Kilicay, Koray; Kaya, Esad; Bayar, Ismail [Dept. of Mechanical Engineering, Eskisehir Osmangazi University, Eskisehir (Turkmenistan)

2016-08-15

In this study, a 90MnCrV8 steel surface was coated with aluminum oxide and chromium oxide powders through the Atmospheric plasma spray (APS) and Plasma transferred arc (PTA) methods. The effects of PTA surface melting on the microstructure, hardness, and wear behavior were investigated. The microstructures of plasma-sprayed and modified layers were characterized by Optical microscopy (OM), Scanning electron microscopy (SEM) and Energy dispersive X-ray spectroscopy (EDS). The dry-sliding wear properties of the samples were determined through the ball-on-disk wear test method. Voids, cracks, and nonhomogeneous regions were observed in the microstructure of the APS ceramic-coated surface. These microstructure defects were eliminated by the PTA welding process. The microhardness of the samples was increased. Significant reductions in wear rate were observed after the PTA surface modification. The wear resistance of ceramic coatings increased 7 to 12 times compared to that of the substrate material.

Heat transfer enhancement using 2MHz ultrasound.

Science.gov (United States)

Bulliard-Sauret, Odin; Ferrouillat, Sebastien; Vignal, Laure; Memponteil, Alain; Gondrexon, Nicolas

2017-11-01

The present work focuses on possible heat transfer enhancement from a heating plate towards tap water in forced convection by means of 2MHz ultrasound. The thermal approach allows to observe the increase of local convective heat transfer coefficients in the presence of ultrasound and to deduce a correlation between ultrasound power and Nusselt number. Heat transfer coefficient under ultrasound remains constant while heat transfer coefficient under silent conditions increases with Reynolds number from 900 up to 5000. Therefore, heat transfer enhancement factor ranges from 25% up to 90% for the same energy conditions (supplied ultrasonic power=110W and supplied thermal power=450W). In the same time cavitational activity due to 2MHz ultrasound emission was characterized from mechanical and chemical viewpoints without significant results. At least, Particle Image Velocimetry (PIV) measurements have been performed in order to investigate hydrodynamic modifications due to the presence of 2MHz ultrasound. It was therefore possible to propose a better understanding of heat transfer enhancement mechanism with high frequency ultrasound. Copyright © 2017 Elsevier B.V. All rights reserved.

Improving safety margins for control room habitability, through heating/ventilation/air conditioning modifications

International Nuclear Information System (INIS)

Beach, D.R.; Fillingim, W.; Bell, G.; Eurich, R.G.

1989-01-01

The Fort Calhoun power station began operation in September 1973. Since that time, modifications to the plant have required the addition of a substantial number of electrical and control components in the control room, which has resulted in an increased heat load in this area. Additionally, NUREG-0737, Item III.D.3.4, imposed requirements on the ventilating system related to protection of personnel from the effects of toxic and radioactive gas releases, which were not considered in the original design. Omaha Public Power District (OPPD) has recently undertaken a major modification to the Fort Calhoun station control room ventilating system to improve the safety margins for control room habitability. The goals of the modification were to achieve adequate cooling capacity with fully redundant equipment, improve habitability under accident conditions, and eliminate several potential problems related to steam line break and equipment qualification. Additionally, the scope of the project grew as design problems emerged

Modification of a recuperator construction with CFD methods

Directory of Open Access Journals (Sweden)

Ludwig Wojciech

2017-12-01

Full Text Available The purpose of the work was initial modification of the construction of a commercially produced heat exchanger – recuperator with CFD (computational fluid dynamics methods, based on designs and process parameters which were provided. Uniformity of gas distribution in the space between the tubes of the apparatus as well as the pressure drop in it were taken as modification criteria. Uniformity of the gas velocity field between the tubes of the heat exchanger should cause equalization of the local individual heat transfer coefficient values and temperature value. Changes of the apparatus construction which do not worsen work conditions of the equipment, but cause savings of constructional materials (elimination or shortening some parts of the apparatus were taken into consideration.

7 CFR 765.401 - Conditions for transfer of real estate and chattel security.

Science.gov (United States)

2010-01-01

... 7 Agriculture 7 2010-01-01 2010-01-01 false Conditions for transfer of real estate and chattel security. 765.401 Section 765.401 Agriculture Regulations of the Department of Agriculture (Continued) FARM... Security and Assumption of Debt § 765.401 Conditions for transfer of real estate and chattel security. (a...

Lunar Cube Transfer Trajectory Options

Science.gov (United States)

Folta, David; Dichmann, Donald James; Clark, Pamela E.; Haapala, Amanda; Howell, Kathleen

2015-01-01

Numerous Earth-Moon trajectory and lunar orbit options are available for Cubesat missions. Given the limited Cubesat injection infrastructure, transfer trajectories are contingent upon the modification of an initial condition of the injected or deployed orbit. Additionally, these transfers can be restricted by the selection or designs of Cubesat subsystems such as propulsion or communication. Nonetheless, many trajectory options can b e considered which have a wide range of transfer duration, fuel requirements, and final destinations. Our investigation of potential trajectories highlights several options including deployment from low Earth orbit (LEO) geostationary transfer orbits (GTO) and higher energy direct lunar transfer and the use of longer duration Earth-Moon dynamical systems. For missions with an intended lunar orbit, much of the design process is spent optimizing a ballistic capture while other science locations such as Sun-Earth libration or heliocentric orbits may simply require a reduced Delta-V imparted at a convenient location along the trajectory.

Experimental research on single-phase heat transfer characteristics in a vertical circular tube under marine conditions

International Nuclear Information System (INIS)

Du Sijia; Zhang Hong; Jia Baoshan

2011-01-01

Experiments have been conducted to study the heat transfer characteristics of single-phase forced circulation when the test tube was under different marine conditions. The experiments measured the wall temperature of test tube to calculate the heat transfer coefficients at different circumferential places. When the test tube was under inclined conditions, the heat transfer coefficient increased at downside and decreased at upside of test tube because of buoyancy effect. When the test tube was under rolling conditions, the heat transfer coefficients fluctuated with the rolling motions, and the Coriolis force dominated the heat transfer fluctuation during the rolling motion. CFD method was used to simulate the heat transfer phenomena under marine conditions, and the results were accord to the experimental phenomena. (authors)

An Efficient Topology for Wireless Power Transfer over a Wide Range of Loading Conditions

Directory of Open Access Journals (Sweden)

Tianqing Li

2018-01-01

Full Text Available Although an inductive power transfer (IPT system can transfer power efficiently in full-load conditions, its efficiency obviously decreases in light-load conditions. To solve this problem, based on a two-coil IPT system with a series-series compensation topology, a single-ended primary-inductor converter is introduced at the secondary side. By adjusting the set effective value of the current in the primary coil, the converter input voltage changes to maintain the equivalent input resistance of the converter in an optimal condition. The system can then transfer the power efficiently with the wide load conditions. Moreover, the system operates at a constant resonance frequency with a high power factor. Both the simulation and experimentation of a prototype with a 10 W IPT system demonstrate the effectiveness of the proposed topology for wireless power transfer.

Heat transfer in intermediate heat exchanger under low flow rate conditions

International Nuclear Information System (INIS)

Mochizuki, H.

2008-01-01

The present paper describes the heat transfer in intermediate heat exchangers (IHXs) of liquid metal cooled fast reactors when flow rate is low such as a natural circulation condition. Although empirical correlations of heat transfer coefficients for IHX were derived using test data at the fast reactor 'Monju' and 'Joyo' and also at the 50 MW steam generator facility, the heat transfer coefficient was very low compared to the well known correlation for liquid metals proposed by Seban-Shimazaki. The heat conduction in IHX was discussed as a possible cause of the low Nusselt number. As a result, the heat conduction is not significant under the natural circulation condition, and the heat conduction term in the energy equation can be neglected in the one-dimensional plant dynamics calculation. (authors)

Fuel conditioning facility zone-to-zone transfer administrative controls

International Nuclear Information System (INIS)

Pope, C. L.

2000-01-01

The administrative controls associated with transferring containers from one criticality hazard control zone to another in the Argonne National Laboratory (ANL) Fuel Conditioning Facility (FCF) are described. FCF, located at the ANL-West site near Idaho Falls, Idaho, is used to remotely process spent sodium bonded metallic fuel for disposition. The process involves nearly forty widely varying material forms and types, over fifty specific use container types, and over thirty distinct zones where work activities occur. During 1999, over five thousand transfers from one zone to another were conducted. Limits are placed on mass, material form and type, and container types for each zone. Ml material and containers are tracked using the Mass Tracking System (MTG). The MTG uses an Oracle database and numerous applications to manage the database. The database stores information specific to the process, including material composition and mass, container identification number and mass, transfer history, and the operators involved in each transfer. The process is controlled using written procedures which specify the zone, containers, and material involved in a task. Transferring a container from one zone to another is called a zone-to-zone transfer (ZZT). ZZTs consist of four distinct phases, select, request, identify, and completion

Abstracts of international symposium on heat and mass transfer under plasma conditions

International Nuclear Information System (INIS)

1994-01-01

The international symposium on heat and mass transfer under plasma conditions was held on 4-8 July 1994 in Cesme, Izmir, Turkey. The spesialists discussed heat and mass transfer in the field of plasma processing at the meeting. More than 70 papers were presented in the meeting

Abstracts of international symposium on heat and mass transfer under plasma conditions

Energy Technology Data Exchange (ETDEWEB)

NONE

1994-12-31

The international symposium on heat and mass transfer under plasma conditions was held on 4-8 July 1994 in Cesme, Izmir, Turkey. The spesialists discussed heat and mass transfer in the field of plasma processing at the meeting. More than 70 papers were presented in the meeting.

The CANDU 9 fuel transfer system

International Nuclear Information System (INIS)

Keszthelyi, Z.G.; Morikawa, D.T.

1996-01-01

The CANDU 9 fuel transfer system is based on the CANDU 6 and the Ontario Hydro Darlington NGD designs, modified to suit the CANDU 9 requirements. The CANDU 9 new fuel transfer system is very similar to the CANDU 6, with modifications to allow new fuel loading from outside containment, similar to Darlington. The CANDU 9 irradiated fuel transfer system is based on the Darlington irradiated fuel transfer system, with modifications to meet the more stringent containment requirements, improve performance, and match station layout. (author). 2 refs., 6 figs

The CANDU 9 fuel transfer system

Energy Technology Data Exchange (ETDEWEB)

Keszthelyi, Z G [Canadian General Electric Co. Ltd., Peterborough, ON (Canada); Morikawa, D T [Atomic Energy of Canada Ltd., Mississauga, ON (Canada)

1997-12-31

The CANDU 9 fuel transfer system is based on the CANDU 6 and the Ontario Hydro Darlington NGD designs, modified to suit the CANDU 9 requirements. The CANDU 9 new fuel transfer system is very similar to the CANDU 6, with modifications to allow new fuel loading from outside containment, similar to Darlington. The CANDU 9 irradiated fuel transfer system is based on the Darlington irradiated fuel transfer system, with modifications to meet the more stringent containment requirements, improve performance, and match station layout. (author). 2 refs., 6 figs.

Surface modification of nanodiamond through metal free atom transfer radical polymerization

Science.gov (United States)

Zeng, Guangjian; Liu, Meiying; Shi, Kexin; Heng, Chunning; Mao, Liucheng; Wan, Qing; Huang, Hongye; Deng, Fengjie; Zhang, Xiaoyong; Wei, Yen

2016-12-01

Surface modification of nanodiamond (ND) with poly(2-methacryloyloxyethyl phosphorylcholine) [poly(MPC)] has been achieved by using metal free surface initiated atom transfer radical polymerization (SI-ATRP). The ATRP initiator was first immobilized on the surface of ND through direct esterification reaction between hydroxyl group of ND and 2-bromoisobutyryl bromide. The initiator could be employed to obtain ND-poly(MPC) nanocomposites through SI-ATRP using an organic catalyst. The final functional materials were characterized by 1H nuclear magnetic resonance, transmission electron microscopy, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy and thermo gravimetric analysis in detailed. All of these characterization results demonstrated that ND-poly(MPC) have been successfully obtained via metal free photo-initiated SI-ATRP. The ND-poly(MPC) nanocomposites shown enhanced dispersibility in various solvents as well as excellent biocompatibility. As compared with traditional ATRP, the metal free ATRP is rather simple and effective. More importantly, this preparation method avoided the negative influence of metal catalysts. Therefore, the method described in this work should be a promising strategy for fabrication of polymeric nanocomposites with great potential for different applications especially in biomedical fields.

Biomimetic surface modification of polypropylene by surface chain transfer reaction based on mussel-inspired adhesion technology and thiol chemistry

Energy Technology Data Exchange (ETDEWEB)

Niu, Zhijun; Zhao, Yang; Sun, Wei; Shi, Suqing, E-mail: shisq@nwu.edu.cn; Gong, Yongkuan

2016-11-15

Highlights: • Biomimetic surface modification of PP was successfully conducted by integrating mussel-inspired technology, thiol chemistry and cell outer membranes-like structures. • The resultant biomimetic surface exhibits good interface and surface stability. • The obvious suppression of protein adsorption and platelet adhesion is also achieved. • The residue thoil groups on the surface could be further functionalized. - Abstract: Biomimetic surface modification of polypropylene (PP) is conducted by surface chain transfer reaction based on the mussel-inspired versatile adhesion technology and thiol chemistry, using 2-methacryloyloxyethylphosphorylcholine (MPC) as a hydrophilic monomer mimicking the cell outer membrane structure and 2,2-azobisisobutyronitrile (AIBN) as initiator in ethanol. A layer of polydopamine (PDA) is firstly deposited onto PP surface, which not only offers good interfacial adhesion with PP, but also supplies secondary reaction sites (-NH{sub 2}) to covalently anchor thiol groups onto PP surface. Then the radical chain transfer to surface-bonded thiol groups and surface re-initiated polymerization of MPC lead to the formation of a thin layer of polymer brush (PMPC) with cell outer membrane mimetic structure on PP surface. X-ray photoelectron spectrophotometer (XPS), atomic force microscopy (AFM) and water contact angle measurements are used to characterize the PP surfaces before and after modification. The protein adsorption and platelet adhesion experiments are also employed to evaluate the interactions of PP surface with biomolecules. The results show that PMPC is successfully grafted onto PP surface. In comparison with bare PP, the resultant PP-PMPC surface exhibits greatly improved protein and platelet resistance performance, which is the contribution of both increased surface hydrophilicity and zwitterionic structure. More importantly, the residue thiol groups on PP-PMPC surface create a new pathway to further functionalize such

Biomimetic surface modification of polypropylene by surface chain transfer reaction based on mussel-inspired adhesion technology and thiol chemistry

International Nuclear Information System (INIS)

Niu, Zhijun; Zhao, Yang; Sun, Wei; Shi, Suqing; Gong, Yongkuan

2016-01-01

Highlights: • Biomimetic surface modification of PP was successfully conducted by integrating mussel-inspired technology, thiol chemistry and cell outer membranes-like structures. • The resultant biomimetic surface exhibits good interface and surface stability. • The obvious suppression of protein adsorption and platelet adhesion is also achieved. • The residue thoil groups on the surface could be further functionalized. - Abstract: Biomimetic surface modification of polypropylene (PP) is conducted by surface chain transfer reaction based on the mussel-inspired versatile adhesion technology and thiol chemistry, using 2-methacryloyloxyethylphosphorylcholine (MPC) as a hydrophilic monomer mimicking the cell outer membrane structure and 2,2-azobisisobutyronitrile (AIBN) as initiator in ethanol. A layer of polydopamine (PDA) is firstly deposited onto PP surface, which not only offers good interfacial adhesion with PP, but also supplies secondary reaction sites (-NH 2 ) to covalently anchor thiol groups onto PP surface. Then the radical chain transfer to surface-bonded thiol groups and surface re-initiated polymerization of MPC lead to the formation of a thin layer of polymer brush (PMPC) with cell outer membrane mimetic structure on PP surface. X-ray photoelectron spectrophotometer (XPS), atomic force microscopy (AFM) and water contact angle measurements are used to characterize the PP surfaces before and after modification. The protein adsorption and platelet adhesion experiments are also employed to evaluate the interactions of PP surface with biomolecules. The results show that PMPC is successfully grafted onto PP surface. In comparison with bare PP, the resultant PP-PMPC surface exhibits greatly improved protein and platelet resistance performance, which is the contribution of both increased surface hydrophilicity and zwitterionic structure. More importantly, the residue thiol groups on PP-PMPC surface create a new pathway to further functionalize such

Asymmetrical transfer effects of cognitive bias modification: Modifying attention to threat influences interpretation of emotional ambiguity, but not vice versa

OpenAIRE

Bowler, J.O.; Hoppitt, L.; Illingworth, J.; Dalgleish, T.; Ononaiye, M.; Perez-Olivas, G.; Mackintosh, B.

2017-01-01

Background and objectives: It is well established that attention bias and interpretation bias each have a key role in the development and continuation of anxiety. How the biases may interact with one another in anxiety is, however, poorly understood. Using cognitive bias modification techniques, the present study examined whether training a more positive interpretation bias or attention bias resulted in transfer of effects to the untrained cognitive domain. Differences in anxiety reactivity t...

A simple heat transfer model for a heat flux plate under transient conditions

International Nuclear Information System (INIS)

Ryan, L.; Dale, J.D.

1985-01-01

Heat flux plates are used for measuring rates of heat transfer through surfaces under steady state and transient conditions. Their usual construction is to have a resistive layer bounded by thermopiles and an exterior layer for protection. If properly designed and constructed a linear relationship between the thermopile generated voltage and heat flux results and calibration under steady state conditions is straight forward. Under transient conditions however the voltage output from a heat flux plate cannot instantaneously follow the heat flux because of the thermal capacitance of the plate and the resulting time lag. In order to properly interpret the output of a heat flux plate used under transient conditions a simple heat transfer model was constructed and tested. (author)

PLUGGING AND UNPLUGGING OF WASTE TRANSFER PIPELINES

International Nuclear Information System (INIS)

Ebadian, M.A.

1999-01-01

This project, which began in FY97, involves both the flow loop research on plugging and unplugging of waste transfer pipelines, and the large-scale industrial equipment test of plugging locating and unplugging technologies. In FY98, the related work was performed under the project name ''Mixing, Settling, and Pipe Unplugging of Waste Transfer Lines.'' The mixing, settling, and pipeline plugging and unplugging are critical to the design and maintenance of a waste transfer pipeline system, especially for the High-Level Waste (HLW) pipeline transfer. The major objective of this work is to recreate pipeline plugging conditions for equipment testing of plug locating and removal and to provide systematic operating data for modification of equipment design and enhancement of performance of waste transfer lines used at DOE sites. As the waste tank clean-out and decommissioning program becomes active at the DOE sites, there is an increasing potential that the waste slurry transfer lines will become plugged and unable to transport waste slurry from one tank to another or from the mixing tank to processing facilities. Transfer systems may potentially become plugged if the solids concentration of the material being transferred increases beyond the capability of the prime mover or if upstream mixing is inadequately performed. Plugging can occur due to the solids' settling in either the mixing tank, the pumping system, or the transfer lines. In order to enhance and optimize the slurry's removal and transfer, refined and reliable data on the mixing, sampling, and pipe unplugging systems must be obtained based on both laboratory-scale and simulated in-situ operating conditions

Pregnancy Rates After Compulsatory One and Conditional Two Embriyo Transfer

Directory of Open Access Journals (Sweden)

Seyhan Gümüşlü

2013-06-01

Full Text Available Objective: To predict our pregnancy rates after compulsatory one and conditional two embriyo transfer (ET number. Design: Retrospective Analysis Materiyal and Methods: One or two embryo transferred 362 patient were analyzed between March 2010 and September 2011. Results: Our clinical pregnancy rate was 31% and implantation rate was 25%. Our pregnancy rates after one or two ET were 30 and 32 % respectively ( P>0.05. We transferred embryos at second, third day or blastocyst stage. Pregnancy rates were 19, 30 and 48 % respectively (p< 0.001, implantation rates were 14.5, 23.5 and 42.4 % respectively ( P< 0.001. Our freezing rate was 39.5 %. Not to have freezing quality embrios or to have increased the the pregnancy rate from 21% to %45 significantly. When one embriyo transfered 95 % single and 5 % twins observed. When two embryos were transfered 81% single,17% twin and 2 % triplets observed. Conclusion: Pregnancy rates for one or two ET were statistically similar. If embryo quality allows us to culture up to blastocyt stage pregnancy rates were statistically increased. New Turkish ET policy resulted 95 % to 81 % single gestational sacs according to 1 or 2 ET at Gazi University IVF center.

Conditional Cash Transfer against Child Labor: Indonesia Program Keluarga Harapan

Science.gov (United States)

Lee, Kye Woo; Hwang, Miae

2016-01-01

This study aims to analyze whether subsidies provided by the Indonesian conditional cash transfer against child labor program (Program Keluarga Harapan: PKH) were sufficient for children to stop working and go back to schooling. Ex-post evaluations of the program found that it did not improve children's enrollment rate and reduce child labor…

76 FR 51878 - Modifications of Certain Derivative Contracts; Correction

Science.gov (United States)

2011-08-19

...) * * * (1) Both the party transferring or assigning its rights and obligations under the derivative contract... Modifications of Certain Derivative Contracts; Correction AGENCY: Internal Revenue Service (IRS), Treasury... temporary regulations (TD 9538) that address when a transfer or assignment of certain derivative contracts...

Modifications in agricultural and animal breeding current operations to reduce the contamination of food chains

International Nuclear Information System (INIS)

Maubert, Henry; Renard, Philippe

1997-01-01

After a nuclear accident it is compulsory to reduce as much as possible the population exposure to radioactive aerosols deposed upon soils and different surfaces. The radio-agronomic countermeasures are protection directives applicable to the agricultural system and agro-alimentary chain which enable to implement this commandment. Their intrinsic and cumulated efficiency, the conditions and preoccupations of implementation are now better recognized especially now by their large scale application after the Chernobyl accident. As modifications in the current agricultural operation two procedures are mentioned: the rehabilitation techniques and the utilization of adjuvants. Concerning modifications in the current animal breeding methodology in the specific conditions of animal production and restricted pasturage there are discussed methods of diminishing the metabolic transfer to milk and meat and removing radioactivity by proper and simpler agro-alimentary processing and culinary preparations

Influence of the boundary conditions on heat and mass transfer in spacer-filled channels

Science.gov (United States)

Ciofalo, M.; La Cerva, M. F.; Di Liberto, M.; Tamburini, A.

2017-11-01

The purpose of this study is to discuss some problems which arise in heat or mass transfer in complex channels, with special reference to the spacer-filled channels adopted in membrane processes. Among the issues addressed are the consistent definition of local and mean heat or mass transfer coefficients; the influence of the wall boundary conditions; the influence of one-side versus two-side heat/mass transfer. Most of the results discussed were obtained by finite volume CFD simulations concerning heat transfer in Membrane Distillation or mass transfer in Electrodialysis and Reverse Electrodialysis, but many of the conclusions apply also to different processes involving geometrically complex channels

Heat transfer study under supercritical pressure conditions

International Nuclear Information System (INIS)

Yamashita, Tohru; Yoshida, Suguru; Mori, Hideo; Morooka, Shinichi; Komita, Hideo; Nishida, Kouji

2003-01-01

Experiments were performed on heat transfer and pressure drop of a supercritical pressure fluid flowing upward in a uniformly heated vertical tube of a small diameter, using HCFC22 as a test fluid. Following results were obtained. (1) Characteristics of the heat transfer are similar to those for the tubes of large diameter. (2) The effect of tube diameter on the heat transfer was seen for a 'normal heat transfer, but not for a 'deteriorated' heat transfer. (3) The limit heat flux for the occurrence of deterioration in heat transfer becomes larger with smaller diameter tube. (4) The Watts and Chou correlation has the best prediction performance for the present data in the 'normal' heat transfer region. (5) Frictional pressure drop becomes smaller than that for an isothermal flow in the region near the pseudocritical point, and this reduction was more remarkable for the deteriorated' heat transfer. (author)

A study on gap heat transfer of LWR fuel rods under reactivity initiated accident conditions

International Nuclear Information System (INIS)

Fujishiro, Toshio

1984-03-01

Gap heat transfer between fuel pellet and cladding have a large influence on the LWR fuel behaviors under reactivity initiated accident (RIA) conditions. The objective of the present study is to investigate the effects of gap heat transfer on RIA fuel behaviors based on the results of the gap-gas parameter tests in NSRR and on their analysis with NSR-77 code. Through this study, transient variations of gap heat transfer, the effects of the gap heat transfer on fuel thermal behaviors and on fuel failure, effects of pellet-cladding sticking by eutectic formation, and the effects of cladding collapse under high external pressure have been clearified. The studies have also been performed on the applicability and its limit of modified Ross and Stoute equation which is extensively utilized to evaluate the gap heat transfer coefficient in the present fuel behavior codes. The method to evaluate the gap conductance to the conditions beyond the applicability limit of the Ross and Stoute equation has also been proposed. (author)

Materials surface modification by plasma bombardment under simultaneous erosion and redeposition conditions

International Nuclear Information System (INIS)

Hirooka, Y.; Goebel, D.M.; Conn, R.W.

1986-07-01

The first in-depth investigation of surface modification of materials by continuous, high-flux argon plasma bombardment under simultaneous erosion and redeposition conditions have been carried out for copper and 304 stainless steel using the PISCES facility. The plasma bombardment conditions are: incident ion flux range from 10 17 to 10 19 ions sec -1 cm -2 , total ion fluence is controlled between 10 19 and 10 22 ions cm -2 , electron temperature range from 5 to 15 eV, and plasma density range from 10 11 to 10 13 cm -3 . The incident ion energy is 100 eV. The sample temperature is between 300 and 700K. Under redeposition dominated conditions, the material erosion rate due to the plasma bombardment is significantly smaller (by a factor up to 10) than that can be expected from the classical ion beam sputtering yield data. It is found that surface morphologies of redeposited materials strongly depend on the plasma bombardment condition. The effect of impurities on surface morphology is elucidated in detail. First-order modelings are implemented to interpret the reduced erosion rate and the surface evolution. Also, fusion related surface properties of redeposited materials such as hydrogen reemission and plasma driven permeation have been characterized

An acyltransferase gene that putatively functions in anthocyanin modification was horizontally transferred from Fabaceae into the genus Cuscuta

Directory of Open Access Journals (Sweden)

Ting Sun

2016-06-01

Full Text Available Horizontal gene transfer (HGT refers to the flow of genetic materials to non-offspring, and occasionally HGT in plants can improve the adaptation of organisms in new niches due to expanded metabolic capability. Anthocyanins are an important group of water-soluble red, purple, or blue secondary metabolites, whose diversity results from modification after the main skeleton biosynthesis. Cuscuta is a stem holoparasitic genus, whose members form direct connection with hosts to withdraw water, nutrients, and macromolecules. Such intimate association is thought to increase the frequency of HGT. By transcriptome screening for foreign genes in Cuscuta australis, we discovered that one gene encoding a putative anthocyanin acyltransferase gene of the BAHD family, which is likely to be involved in anthocyanin modification, was acquired by C. australis from Fabaceae through HGT. The anthocyanin acyltransferase-like (AT-like gene was confirmed to be present in the genome assembly of C. australis and the transcriptomes of Cuscuta pentagona. The higher transcriptional level in old stems is consistent with its putative function in secondary metabolism by stabilizing anthocyanin at neutral pH and thus HGT of this AT-like gene may have improved biotic and abiotic resistance of Cuscuta.

On the transfer matrix of the supersymmetric eight-vertex model. I. Periodic boundary conditions

Science.gov (United States)

Hagendorf, Christian; Liénardy, Jean

2018-03-01

The square-lattice eight-vertex model with vertex weights a, b, c, d obeying the relation (a^2+ab)(b^2+ab) = (c^2+ab)(d^2+ab) and periodic boundary conditions is considered. It is shown that the transfer matrix of the model for L  =  2n  +  1 vertical lines and periodic boundary conditions along the horizontal direction possesses the doubly degenerate eigenvalue \\Thetan = (a+b){\\hspace{0pt}}2n+1 . This proves a conjecture by Stroganov from 2001. The proof uses the supersymmetry of a related XYZ spin-chain Hamiltonian. The eigenstates of the transfer matrix corresponding to \\Thetan are shown to be the ground states of the spin-chain Hamiltonian. Moreover, for positive vertex weights \\Thetan is the largest eigenvalue of the transfer matrix.

CRISPR-Cas and Restriction-Modification Act Additively against Conjugative Antibiotic Resistance Plasmid Transfer in Enterococcus faecalis.

Science.gov (United States)

Price, Valerie J; Huo, Wenwen; Sharifi, Ardalan; Palmer, Kelli L

2016-01-01

Enterococcus faecalis is an opportunistic pathogen and a leading cause of nosocomial infections. Conjugative pheromone-responsive plasmids are narrow-host-range mobile genetic elements (MGEs) that are rapid disseminators of antibiotic resistance in the faecalis species. Clustered regularly interspaced short palindromic repeat (CRISPR)-Cas and restriction-modification confer acquired and innate immunity, respectively, against MGE acquisition in bacteria. Most multidrug-resistant E. faecalis isolates lack CRISPR-Cas and possess an orphan locus lacking cas genes, CRISPR2, that is of unknown function. Little is known about restriction-modification defense in E. faecalis. Here, we explore the hypothesis that multidrug-resistant E. faecalis strains are immunocompromised. We assessed MGE acquisition by E. faecalis T11, a strain closely related to the multidrug-resistant hospital isolate V583 but which lacks the ~620 kb of horizontally acquired genome content that characterizes V583. T11 possesses the E. faecalis CRISPR3-cas locus and a predicted restriction-modification system, neither of which occurs in V583. We demonstrate that CRISPR-Cas and restriction-modification together confer a 4-log reduction in acquisition of the pheromone-responsive plasmid pAM714 in biofilm matings. Additionally, we show that the orphan CRISPR2 locus is functional for genome defense against another pheromone-responsive plasmid, pCF10, only in the presence of cas9 derived from the E. faecalis CRISPR1-cas locus, which most multidrug-resistant E. faecalis isolates lack. Overall, our work demonstrated that the loss of only two loci led to a dramatic reduction in genome defense against a clinically relevant MGE, highlighting the critical importance of the E. faecalis accessory genome in modulating horizontal gene transfer. Our results rationalize the development of antimicrobial strategies that capitalize upon the immunocompromised status of multidrug-resistant E. faecalis. IMPORTANCE

Tubing modifications for countercurrent chromatography (CCC): Stationary phase retention and separation efficiency.

Science.gov (United States)

Englert, Michael; Vetter, Walter

2015-07-16

Countercurrent chromatography (CCC) is a separation technique in which two immiscible liquid phases are used for the preparative purification of synthetic and natural products. In CCC the number of repetitive mixing and de-mixing processes, the retention of the stationary phase and the mass transfer between the liquid phases are significant parameters that influence the resolution and separation efficiency. Limited mass transfer is the main reason for peak broadening and a low number of theoretical plates along with impaired peak resolution in CCC. Hence, technical improvements with regard to column design and tubing modifications is an important aspect to enhance mixing and mass transfer. In this study we constructed a crimping tool which allowed us to make reproducible, semi-automated modifications of conventional round-shaped tubing. Six crimped tubing modifications were prepared, mounted onto multilayer coils which were subsequently installed in the CCC system. The stationary phase retention of the tubing modifications were compared to the conventional system with unmodified tubing in a hydrophobic, an intermediate and a hydrophilic two-phase solvent system. Generally, the tubing modifications provided higher capabilities to retain the stationary phase depending on the solvent system and flow rates. In the intermediate solvent system the separation efficiency was evaluated with a mixture of six alkyl p-hydroxybenzoates. The peak resolution could be increased up to 50% with one of the tubing modifications compared to the unmodified tubing. Using the most convincing tubing modification at fixed values for the stationary phase retention, a reasonable comparison to the unmodified tubing was achieved. The peak width could be reduced up to 49% and a strong positive impact at increased flow rates regarding peak resolution and theoretical plate number was observed compared to unmodified tubing. It could be concluded that the tubing modification enhanced the interphase

Permit application modifications

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-11-01

This document contains the Permit Application Modifications for the Y-12 Industrial Landfill V site on the Oak Ridge Reservation. These modifications include the assessment of stability of the proposed Landfill V under static and loading conditions. Analyses performed include the general slope stability, veneer stability of the bottom liner and cover system, and a liquefaction potential assessment of the foundation soils.

Permit application modifications

International Nuclear Information System (INIS)

1995-11-01

This document contains the Permit Application Modifications for the Y-12 Industrial Landfill V site on the Oak Ridge Reservation. These modifications include the assessment of stability of the proposed Landfill V under static and loading conditions. Analyses performed include the general slope stability, veneer stability of the bottom liner and cover system, and a liquefaction potential assessment of the foundation soils

Deciphering the Translation Initiation Factor 5A Modification Pathway in Halophilic Archaea

Directory of Open Access Journals (Sweden)

Laurence Prunetti

2016-01-01

Full Text Available Translation initiation factor 5A (IF5A is essential and highly conserved in Eukarya (eIF5A and Archaea (aIF5A. The activity of IF5A requires hypusine, a posttranslational modification synthesized in Eukarya from the polyamine precursor spermidine. Intracellular polyamine analyses revealed that agmatine and cadaverine were the main polyamines produced in Haloferax volcanii in minimal medium, raising the question of how hypusine is synthesized in this halophilic Archaea. Metabolic reconstruction led to a tentative picture of polyamine metabolism and aIF5A modification in Hfx. volcanii that was experimentally tested. Analysis of aIF5A from Hfx. volcanii by LC-MS/MS revealed it was exclusively deoxyhypusinylated. Genetic studies confirmed the role of the predicted arginine decarboxylase gene (HVO_1958 in agmatine synthesis. The agmatinase-like gene (HVO_2299 was found to be essential, consistent with a role in aIF5A modification predicted by physical clustering evidence. Recombinant deoxyhypusine synthase (DHS from S. cerevisiae was shown to transfer 4-aminobutyl moiety from spermidine to aIF5A from Hfx. volcanii in vitro. However, at least under conditions tested, this transfer was not observed with the Hfx. volcanii DHS. Furthermore, the growth of Hfx. volcanii was not inhibited by the classical DHS inhibitor GC7. We propose a model of deoxyhypusine synthesis in Hfx. volcanii that differs from the canonical eukaryotic pathway, paving the way for further studies.

Influences of buoyancy and thermal boundary conditions on heat transfer with naturally-induced flow

International Nuclear Information System (INIS)

Jackson, J.D.; Li, J.

2002-01-01

A fundamental study is reported of heat transfer from a vertical heated tube to air which is induced naturally upwards through it by the action of buoyancy. Measurements of local heat transfer coefficient were made using a specially designed computer-controlled power supply and measurement system for conditions of uniform wall temperature and uniform wall heat flux. The effectiveness of heat transfer proved to be much lower than for conditions of forced convection. It was found that the results could be correlated satisfactorily when presented in terms of dimensionless parameters similar to those used for free convection heat transfer from vertical surfaces provided that the heat transfer coefficients were evaluated using local fluid bulk temperature calculated utilising the measured values of flow rate induced through the system. Additional experiments were performed' with pumped flow. These covered the entire mixed convection region. It was found that the data for naturally-induced flow mapped onto the pumped flow data when presented in terms of Nusselt number ratio (mixed to forced) and buoyancy parameter. Computational simulations of the experiments were performed using an advanced computer code which incorporated a buoyancy-influenced, variable property, developing wall shear flow formulation and a low Reynolds number k-ε turbulence model. These reproduced observed behaviour quite well. (author)

Grouping subjects based on conditioning criteria reveals differences in acquisition rates and in strength of conditioning-specific reflex modification.

Science.gov (United States)

Smith-Bell, Carrie A; Schreurs, Bernard G

2017-11-01

Averaging behavioral data such as the nictitating membrane response (NMR) across subjects can conceal important individual and group differences. Analyses were conducted of NMR data from rabbits that were grouped based on the point during NMR conditioning when subjects produced 8 conditioned responses (CR) in a set of 10 trials. This resulted in five groups (Early Day 1, Late Day 1, Early Day 2, Late Day 2, Early Day 3) in which group differences in CR acquisition rates were found. Percent (%) CRs were not found to increase monotonically and between-session differences in % CR were found. Conditioning-specific reflex modification (CRM) of the NMR is a type of enhanced reflexive responding of the NMR that is detected when the unconditioned stimulus (US) is presented in the absence of the conditioned stimulus (CS) following paired classical conditioning. CRM occurred in some subjects in all five groups. Subjects from both the group that was fastest and the group that was slowest to reach the learning criterion had unconditioned response (UR) topographies following NMR conditioning that strongly resembled the CR-UR response sequence elicited during NMR conditioning. This finding was most pronounced when the US duration used to assess CRM was equivalent to that used during NMR conditioning, further evidence to support the hypothesis that CRM is a CR that has generalized from the CS to the US. While grouping data based on conditioning criteria did not facilitate identifying individuals more predisposed to exhibiting CRM, strong CRM only occurred in the groups that reached the conditioning criterion the fastest. Copyright © 2017 Elsevier Inc. All rights reserved.

State of the art on the heat transfer experiments under supercritical pressure condition

International Nuclear Information System (INIS)

Kim, Hwan Yeol; Song, Chul Hwa

2003-07-01

The SCWR(Super-Critical Water cooled Reactor) is one of the six reactor candidates selected in the Gen-IV project which aims at the development of new reactors with enhanced economy and safety. The SCWR is considered to be a feasible concept of new nuclear power plant if the existing technologies developed in fossil fuel fired plant and LWR technologies together with additional research on several disciplines such as materials, water chemistry and safety. As KAERI takes part in the GIF(Generation IV Forum) for the Gen-IV project, domestic concerns about the SCWR have been recently increased. In order to establish a foundation for the development of SCWR, efforts should be concentrated on the conceptual design of systems and the associated key experiments as well. Heat transfer experiments, among others, under supercritical condition are required for the proper prediction of thermal hydraulic phenomena, which are essential for the thermal hydraulic designs of reactor core. Nevertheless, the experiments have not been performed in Korea yet. This report deals with fundamental surveys on the heat transfer experiments under supercritical conditions, which are required for the understanding of heat transfer characteristics for the thermal hydraulic designs of supercritical reactor core. Investigations on the physical properties of water and CO 2 showed that the physical properties such as density, specific heat, viscosity and thermal conductivity are significantly changed near the pseudo-critical points. The state of the art on the heat transfer characteristics in relation with heat transfer deterioration and heat transfer coefficient is briefly described. In addition, previous experiments with supercritical water as well as supercritical CO 2 and Freon used for an alternating fluid are presented

State of the art on the heat transfer experiments under supercritical pressure condition

Energy Technology Data Exchange (ETDEWEB)

Kim, Hwan Yeol; Song, Chul Hwa

2003-07-01

The SCWR(Super-Critical Water cooled Reactor) is one of the six reactor candidates selected in the Gen-IV project which aims at the development of new reactors with enhanced economy and safety. The SCWR is considered to be a feasible concept of new nuclear power plant if the existing technologies developed in fossil fuel fired plant and LWR technologies together with additional research on several disciplines such as materials, water chemistry and safety. As KAERI takes part in the GIF(Generation IV Forum) for the Gen-IV project, domestic concerns about the SCWR have been recently increased. In order to establish a foundation for the development of SCWR, efforts should be concentrated on the conceptual design of systems and the associated key experiments as well. Heat transfer experiments, among others, under supercritical condition are required for the proper prediction of thermal hydraulic phenomena, which are essential for the thermal hydraulic designs of reactor core. Nevertheless, the experiments have not been performed in Korea yet. This report deals with fundamental surveys on the heat transfer experiments under supercritical conditions, which are required for the understanding of heat transfer characteristics for the thermal hydraulic designs of supercritical reactor core. Investigations on the physical properties of water and CO{sub 2} showed that the physical properties such as density, specific heat, viscosity and thermal conductivity are significantly changed near the pseudo-critical points. The state of the art on the heat transfer characteristics in relation with heat transfer deterioration and heat transfer coefficient is briefly described. In addition, previous experiments with supercritical water as well as supercritical CO{sub 2} and Freon used for an alternating fluid are presented.

Dimensional analysis of boiling heat transfer burnout conditions

International Nuclear Information System (INIS)

El-Mitwally, E.S.; Raafat, N.M.; Darwish, M.A.

1979-01-01

The first criteria in boiling water systems design, such as boiling water reactors, is that no burnout in the core is allowed to exist under any conditions of the reactor operation either during steady state operation or during any of the several postulated accidental transients, such as sudden interruption of coolant flow in the reactor core (due to pump failure or blockage of fuel channel). The aim of the present work is to obtain a correlation for the critical heat flux based on a theoretical study where the mechanism of burn out and the related hydrodynamic and heat transfer equations are considered. 8 refs

Natural printed silk substrate circuit fabricated via surface modification using one step thermal transfer and reduction graphene oxide

Science.gov (United States)

Cao, Jiliang; Huang, Zhan; Wang, Chaoxia

2018-05-01

Graphene conductive silk substrate is a preferred material because of its biocompatibility, flexibility and comfort. A flexible natural printed silk substrate circuit was fabricated by one step transfer of graphene oxide (GO) paste from transfer paper to the surface of silk fabric and reduction of the GO to reduced graphene oxide (RGO) using a simple hot press treatment. The GO paste was obtained through ultrasonic stirring exfoliation under low temperature, and presented excellent printing rheological properties at high concentration. The silk fabric was obtained a surface electric resistance as low as 12.15 KΩ cm-1, in the concentration of GO 50 g L-1 and hot press at 220 °C for 120 s. Though the whiteness and strength decreased with the increasing of hot press temperature and time slowly, the electric conductivity of RGO surface modification silk substrate improved obviously. The surface electric resistance of RGO/silk fabrics increased from 12.15 KΩ cm-1 to 18.05 KΩ cm-1, 28.54 KΩ cm-1 and 32.53 KΩ cm-1 after 10, 20 and 30 washing cycles, respectively. The results showed that the printed silk substrate circuit has excellent washability. This process requires no chemical reductant, and the reduction efficiency and reduction degree of GO is high. This time-effective and environmentally-friendly one step thermal transfer and reduction graphene oxide onto natural silk substrate method can be easily used to production of reduced graphene oxide (RGO) based flexible printed circuit.

Heavy ion induced DNA transfer in biological cells

International Nuclear Information System (INIS)

Vilaithong, T.; Yu, L.D.; Apavatjrut, P.; Phanchaisri, B.; Sangyuenyongpipat, S.; Anuntalabhochai, S.; Brown, I.G.

2004-01-01

Low-energy ion beam bombardment of biological materials for genetic modification purposes has experienced rapid growth in the last decade, particularly for the direct DNA transfer into living organisms including both plants and bacteria. Attempts have been made to understand the mechanisms involved in ion-bombardment-induced direct gene transfer into biological cells. Here we summarize the present status of the application of low-energy ions for genetic modification of living sample materials

Reaction of electron-transfer flavoprotein with electron-transfer flavoprotein-ubiquinone oxidoreductase

International Nuclear Information System (INIS)

Beckmann, J.D.; Frerman, F.E.

1985-01-01

The oxidative half-reaction of electron-transfer flavoprotein (ETF), electron transfer from ETF to electron-transfer flavoprotein-ubiquinone oxidoreductase (ETF-QO), is dependent on complementary surface charges on the two proteins. ETF is the positively charged member of the redox pair. The evidence is based on the pH and ionic strength dependencies of the comproportionation of oxidized ETF and ETF hydroquinone catalyzed by ETF-QO and on the effects of chemical modification of ETF on the comproportionation reaction. Acetylation of one and five epsilon-amino groups of lysyl residues results in 3- and 13-fold increases, respectively, in the K/sub m/ of ETF-QO for ETF but no change in V/sub max/. Amidination, which maintains positive charge at modified loci, has no effect on steady-state kinetic constants. These chemical modifications have no effect on the equilibrium constant for equilibration of ETF redox states. The K/sub m/ of ETF-QO for ETF is pH dependent above pH 8.5, suggesting titration of lysyl residues. The ionic strength dependence of TN/KmETF for the reaction follows the limiting Bronsted equation. The ETF-QO-catalyzed comproportionation reaction exhibits a primary deuterium isotope effect in D 2 O, perhaps indicating the participation of solvent water in the electron-transfer reaction

Chain-end modification of living anionic polybutadiene with diphenylethylenes and styrenes

NARCIS (Netherlands)

Donkers, E.H.D.; Willemse, R.X.E.; Klumperman, B.

2005-01-01

The first step in the transformation of poly(butadienyl)lithium into a macromolecular atom transfer radical polymerization initiator or reversible addition-fragmentation chain transfer agent is the modification of the anionic chain end into a suitable leaving/reinitiating group. We have investigated

Liquid metal heat transfer in heat exchangers under low flow rate conditions

International Nuclear Information System (INIS)

Mochizuki, Hiroyasu

2015-01-01

The present paper describes the liquid metal heat transfer in heat exchangers under low flow rate conditions. Measured data from some experiments indicate that heat transfer coefficients of liquid metals at very low Péclet number are much lower than what are predicted by the well-known empirical relations. The cause of this phenomenon was not fully understood for many years. In the present study, one countercurrent-type heat exchanger is analyzed using three, separated countercurrent heat exchanger models: one is a heat exchanger model in the tube bank region, while the upper and lower plena are modeled as two heat exchangers with a single heat transfer tube. In all three heat exchangers, the same empirical correlation is used in the heat transfer calculation on the tube and the shell sides. The Nusselt number, as a function of the Péclet number, calculated from measured temperature and flow rate data in a 50 MW experimental facility was correctly reproduced by the calculation result, when the calculated result is processed in the same way as the experiment. Finally, it is clarified that the deviation is a superficial phenomenon which is caused by the heat transfer in the plena of the heat exchanger. (author)

Coherently Enhanced Wireless Power Transfer

Science.gov (United States)

Krasnok, Alex; Baranov, Denis G.; Generalov, Andrey; Li, Sergey; Alù, Andrea

2018-04-01

Extraction of electromagnetic energy by an antenna from impinging external radiation is at the basis of wireless communications and wireless power transfer (WPT). The maximum of transferred energy is ensured when the antenna is conjugately matched, i.e., when it is resonant and it has an equal coupling with free space and its load. This condition, however, can be easily affected by changes in the environment, preventing optimal operation of a WPT system. Here, we introduce the concept of coherently enhanced WPT that allows us to bypass this difficulty and achieve dynamic control of power transfer. The approach relies on coherent excitation of the waveguide connected to the antenna load with a backward propagating signal of specific amplitude and phase. This signal creates a suitable interference pattern at the load resulting in a modification of the local wave impedance, which in turn enables conjugate matching and a largely increased amount of extracted energy. We develop a simple theoretical model describing this concept, demonstrate it with full-wave numerical simulations for the canonical example of a dipole antenna, and verify experimentally in both near-field and far-field regimes.

The Influence of Conditional Cash Transfers on Eligible Children and Their Siblings

Science.gov (United States)

Lincove, Jane Arnold; Parker, Adam

2016-01-01

Conditional cash transfers (CCTs) are used to reduce poverty while incentivizing investments in children. Targeting CCTs to certain groups of children can improve efficiency, but positive effects on eligible children may be offset by reductions in investments for ineligible siblings. Using data from Nicaragua, we estimate program effects on…

A mathematical model for localized corrosion in steam generator crevices under heat transfer conditions

International Nuclear Information System (INIS)

Engelhardt, G.; Urquidi-Macdonald, M.; Sikora, J.; Macdonald, D.D.

1995-01-01

A predictive and self-consistent mathematical model has been developed to describe the localized corrosion in steam generators. The model recognizes that the internal and external environment are coupled by the need to conserve charge in the system. Thus, solution of Laplace's equation for the external environment (outside the crevice) provides the boundary condition for the electric potential at the crevice mouth, which is needed for solving the system of mass transfer equations for the internal environment (inside the crevice). Mass transfer by diffusion, ion migration, and convection was considered. Heat and momentum transfer equations are solved simultaneously, with the mass balance equation for each species and the condition of electroneutrality inside the cavity being considered. The model takes into account the porosity and tortuosity in the corrosion product deposit in the crevice. The homogeneous chemical reactions (hydrolysis of the products of the anodic reaction and the autoprotolysis of water) are included in the model. The model, in this preliminary form predicts the solution chemistry, potential drop, and temperature distribution inside the crevice. An order of magnitude estimate of the crevice corrosion rate also obtained. At this point, the model predicts only the steady state solution, but it is recognized that a steady state may not exist under normal conditions

Research on mass transfer and actual performance of the membrane regeneration air-conditioning system

International Nuclear Information System (INIS)

Li, Xiu-Wei; Zhang, Xiao-Song; Chen, Qing

2015-01-01

Highlights: • Experimental research has been made on the membrane air-conditioning system. • We develop mass transfer models for the membrane regeneration process. • The paper exposes the actual performance of the system. • Increase of membrane pairs improves the performance. - Abstract: Absorption air-conditioning system has great advantages in energy conservation and environmental protection. To improve the performance of the traditional system, the membrane regeneration absorption system was proposed. Its COP could approach 6 by regenerating absorbent solution with the ion exchange membranes. However, the theoretical conclusion has not been supported by the experiment. This paper presents the experimental research of the membrane regeneration process. It has investigated the mass transfer process, energy efficiency and actual performance under different working conditions. Based on that, a mass transfer model has been developed and the influences of some key parameters have been exposed. It found the regeneration performance is mainly influenced by the current intensity. The calculation results with the model agree well the experimental data. The actual efficiency was lower than 50%, caused by energy loss in heat and electrochemical reactions. The actual COP is between 1 and 3, lower current intensity and more membrane pairs could improve it.

A test facility for heat transfer, pressure drop and stability studies under supercritical conditions

International Nuclear Information System (INIS)

Sharma, Manish; Pilkhwal, D.S.; Jana, S.S.; Vijayan, P.K.

2013-02-01

Supercritical water (SCW) exhibits excellent heat transfer characteristics and high volumetric expansion coefficient (hence high mass flow rates in natural circulation systems) near pseudo-critical temperature. SCW is being considered as a coolant in some advanced nuclear reactor designs on account of its potential to offer high thermal efficiency, compact size, elimination of steam generator, separator and dryer, making it economically competitive. The elimination of phase change results in elimination of the Critical Heat Flux (CHF) phenomenon. Cooling a reactor at full power with natural instead of forced circulation is generally considered as enhancement of passive safety. In view of this, it is essential to study natural circulation, heat transfer and pressure drop characteristics of supercritical fluids. Carbon-dioxide can be considered to be a good simulant of water for natural circulation at supercritical conditions since the density and viscosity variation of carbon-dioxide follows a parallel curve as that of water at supercritical conditions. Hence, a supercritical pressure natural circulation loop (SPNCL) has been set up in Hall-7, BARC to investigate the heat transfer, pressure drop and stability characteristics of supercritical carbon-dioxide under natural circulation conditions. The details of the experimental facility are presented in this report. (author)

Development of surface wettability characteristics for enhancing pool boiling heat transfer

International Nuclear Information System (INIS)

Kim, Moo Hwan; Jo, Hang Jin

2010-05-01

For several centuries, many boiling experiments have been conducted. Based on literature survey, the characteristic of heating surface in boiling condition played as an important role which mainly influenced to boiling performance. Among many surface factor, the fact that wettability effect is significant to not only the enhancement of critical heat flux(CHF) but also the nucleate boiling heat transfer is also supported by other kinds of boiling experiments. In this regard, the excellent boiling performance (a high CHF and heat transfer performance) in pool boiling could be achieved through some favorable surface modification which satisfies the optimized wettability condition. To find the optimized boiling condition, we design the special heaters to examine how two materials, which have different wettability (e.g. hydrophilic and hydrophobic), affect the boiling phenomena. The special heaters have hydrophobic dots on hydrophilic surface. The contact angle of hydrophobic surface is 120 .deg. to water at the room temperature. The contact angle of hydrophilic surface is 60 .deg. at same conditions. To conduct the experiment with new surface condition, we developed new fabrication method and design the pool boiling experimental apparatus. Through this facility, we can the higher CHF on pattern surface than that on hydrophobic surface, and the higher boiling heat transfer performance on pattern surface than that on hydrophilic surface. Based on this experimental results, we concluded that we proposed new heating surface condition and surface fabrication method to realize the best boiling condition by modified heating surface condition

Development of Surface Modification Techniques for Enhanced Safety of Light Water Reactors: Recent Progress and Future Direction at THLAB

Energy Technology Data Exchange (ETDEWEB)

Seo, Gwang Hyeok; Jeong, Ui Ju; Son, Hong Hyun; Jeun, Gyoo Dong; Kim, Sung Joong [Hanyang University, Daejeon (Korea, Republic of)

2016-05-15

They concluded that the CHF enhancement in nanofluid boiling was mainly affected by the surface characteristics of the developed layer. Furthermore, an introduction of surface modification can be utilized to secure the safety of nuclear reactor systems. At many components of the reactor systems, energetic boiling heat transfer occurs, and potential thermal attack to the systems is expected under normal or accident environments. In particular, during a reactor operation, fission energy is deposited in the fuel assemblies in a core. Also, under severe conditions, failure of a reactor vessel may occur by high temperature molten materials. In this article, we introduce the surface modification techniques and recent achievements. After a brief description of each deposition mechanism, an assessment of thermal margin for both the technologies is discussed based on pool boiling experiments conducted at THLAB. Moreover, in the latter part of each chapter, experimental facilities for applied heat transfer tests to consider reactor environments are presented.

Railcar waste transfer system hydrostatic test

International Nuclear Information System (INIS)

Ellingson, S.D.

1997-01-01

Recent modifications have been performed on the T-Plant Railcar Waste Transfer System, This Acceptance Test Procedure (ATP) has been prepared to demonstrate that identified piping welds and mechanical connections incorporated during the modification are of high integrity and are acceptable for service. This will be achieved by implementation of a hydrostatic leak test

The effect of cooling conditions on convective heat transfer and flow in a steam-cooled ribbed duct

International Nuclear Information System (INIS)

Shui, Linqi; Gao, Jianmin; Shi, Xiaojun; Liu, Jiazeng; Xu, Liang

2014-01-01

This work presents a numerical and experimental investigation on the heat transfer and turbulent flow of cooling steam in a rectangular duct with 90 .deg. ribs and studies the effect of cooling conditions on the heat transfer augmentation of steam. In the calculation, the variation range of Reynolds is from 10,000 to 190,000, the inlet temperature varies from 300 .deg. C to 500 .deg. C and the outlet pressure is from 0.5MPa to 6MPa. The aforementioned wide ranges of flow parameters cover the actual operating condition of coolant used in the gas turbine blades. The computations are carried with four turbulence models (the standard k-ε, the renormalized group (RNG) k-ε, the Launder-Reece-Rodi (LRR) and the Speziale-Sarkar-Gatski (SSG) turbulence models). The comparison of numerical and experimental results reveals that the SSG turbulence model is suitable for steam flow in the ribbed duct. Therefore, adopting the conjugate calculation technique, further study on the steam heat transfer and flow characteristics is performed with SSG turbulence model. The results show that the variation of cooling condition strongly impacts the forced convection heat transfer of steam in the ribbed duct. The cooling supply condition of a relative low temperature and medium pressure could bring a considerable advantage on steam thermal enhancement. In addition, comparing the heat transfer level between steam flow and air flow, the performance advantage of using steam is also influenced by the cooling supply condition. Changing Reynolds number has little effect on the performance superiority of steam cooling. Increasing pressure would strengthen the advantage, but increasing temperature gives an opposite result.

The effect of cooling conditions on convective heat transfer and flow in a steam-cooled ribbed duct

Energy Technology Data Exchange (ETDEWEB)

Shui, Linqi; Gao, Jianmin; Shi, Xiaojun; Liu, Jiazeng; Xu, Liang [Xi' an Jiaotong University, Xi' an (China)

2014-01-15

This work presents a numerical and experimental investigation on the heat transfer and turbulent flow of cooling steam in a rectangular duct with 90 .deg. ribs and studies the effect of cooling conditions on the heat transfer augmentation of steam. In the calculation, the variation range of Reynolds is from 10,000 to 190,000, the inlet temperature varies from 300 .deg. C to 500 .deg. C and the outlet pressure is from 0.5MPa to 6MPa. The aforementioned wide ranges of flow parameters cover the actual operating condition of coolant used in the gas turbine blades. The computations are carried with four turbulence models (the standard k-ε, the renormalized group (RNG) k-ε, the Launder-Reece-Rodi (LRR) and the Speziale-Sarkar-Gatski (SSG) turbulence models). The comparison of numerical and experimental results reveals that the SSG turbulence model is suitable for steam flow in the ribbed duct. Therefore, adopting the conjugate calculation technique, further study on the steam heat transfer and flow characteristics is performed with SSG turbulence model. The results show that the variation of cooling condition strongly impacts the forced convection heat transfer of steam in the ribbed duct. The cooling supply condition of a relative low temperature and medium pressure could bring a considerable advantage on steam thermal enhancement. In addition, comparing the heat transfer level between steam flow and air flow, the performance advantage of using steam is also influenced by the cooling supply condition. Changing Reynolds number has little effect on the performance superiority of steam cooling. Increasing pressure would strengthen the advantage, but increasing temperature gives an opposite result.

Calculations of combined radiation and convection heat transfer in rod bundles under emergency cooling conditions

International Nuclear Information System (INIS)

Sun, K.H.; Gonzalez-Santalo, J.M.; Tien, C.L.

1976-01-01

A model has been developed to calculate the heat transfer coefficients from the fuel rods to the steam-droplet mixture typical of Boiling Water Reactors under Emergency Core Cooling System (ECCS) operation conditions during a postulated loss-of-coolant accident. The model includes the heat transfer by convection to the vapor, the radiation from the surfaces to both the water droplets and the vapor, and the effects of droplet evaporation. The combined convection and radiation heat transfer coefficient can be evaluated with respect to the characteristic droplet size. Calculations of the heat transfer coefficient based on the droplet sizes obtained from the existing literature are consistent with those determined empirically from the Full-Length-Emergency-Cooling-Heat-Transfer (FLECHT) program. The present model can also be used to assess the effects of geometrical distortions (or deviations from nominal dimensions) on the heat transfer to the cooling medium in a rod bundle

Comments on contingency management and conditional cash transfers.

Science.gov (United States)

Higgins, Stephen T

2010-10-01

This essay discusses research on incentive-based interventions to promote healthy behavior change, contingency management (CM) and conditional cash transfers (CCT). The overarching point of the essay is that CM and CCT are often treated as distinct areas of inquiry when at their core they represent a common approach. Some potential bi-directional benefits of recognizing this commonality are discussed. Distinct intellectual traditions probably account for the separate paths of CM and CCT to date, with the former being rooted in behavioral psychology and the latter in microeconomics. It is concluded that the emerging field of behavioral economics, which is informed by and integrates principles of each of those disciplines, may provide the proper conceptual framework for integrating CM and CCT.

A Question of Control? Examining the Role of Control Conditions in Experimental Psychopathology using the Example of Cognitive Bias Modification Research.

Science.gov (United States)

Blackwell, Simon E; Woud, Marcella L; MacLeod, Colin

2017-10-26

While control conditions are vitally important in research, selecting the optimal control condition can be challenging. Problems are likely to arise when the choice of control condition is not tightly guided by the specific question that a given study aims to address. Such problems have become increasingly apparent in experimental psychopathology research investigating the experimental modification of cognitive biases, particularly as the focus of this research has shifted from theoretical questions concerning mechanistic aspects of the association between cognitive bias and emotional vulnerability, to questions that instead concern the clinical efficacy of 'cognitive bias modification' (CBM) procedures. We discuss the kinds of control conditions that have typically been employed in CBM research, illustrating how difficulties can arise when changes in the types of research questions asked are not accompanied by changes in the control conditions employed. Crucially, claims made on the basis of comparing active and control conditions within CBM studies should be restricted to those conclusions allowed by the specific control condition employed. CBM studies aiming to establish clinical utility are likely to require quite different control conditions from CBM studies aiming to illuminate mechanisms. Further, conclusions concerning the clinical utility of CBM interventions cannot necessarily be drawn from studies in which the control condition has been chosen to answer questions concerning mechanisms. Appreciating the need to appropriately alter control conditions in the transition from basic mechanisms-focussed investigations to applied clinical research could greatly facilitate the translational process.

Accommodating for plant modifications

International Nuclear Information System (INIS)

Weirich, P.H.

1977-01-01

Modification to a nuclear power plant may have different causes: 1) new instructions by the authorities; 2) changes of the marginal conditions on the construction site; 3) progress in the technological development. - Examples from different plants are supposed to demonstrate how such changes influence the planning or the construction and how they are integrated in the process of preparation. A distinction can be made between modifications before the completion of the submission of the order, during the phase of preparatory planning and during the construction phase. Of great importance are especially modifications made after the beginning of the construction works, since, in general, there is little scope for technical modifications and since consequences for the time schedule are to be expected. (orig.) [de

Do Conditional Cash Transfers for Schooling Generate Lasting Benefits? A Five-Year Followup of PROGRESA/Oportunidades

Science.gov (United States)

Behrman, Jere R.; Parker, Susan W.; Todd, Petra E.

2011-01-01

Conditional cash transfer (CCT) programs link public transfers to human capital investment in hopes of alleviating current poverty and reducing its intergenerational transmission. However, little is known about their long-term impacts. This paper evaluates longer-run impacts on schooling and work of the best-known CCT program, Mexico's…

Conditions that allow for effective transfer of membrane proteins onto nitrocellulose membrane in Western blots.

Science.gov (United States)

Abeyrathne, Priyanka D; Lam, Joseph S

2007-04-01

A major hurdle in characterizing bacterial membrane proteins by Western blotting is the ineffectiveness of transferring these proteins from sodium dodecyl sulfate -- polyacrylamide gel electrophoresis (SDS-PAGE) gel onto nitrocellulose membrane, using standard Western blot buffers and electrophoretic conditions. In this study, we compared a number of modified Western blotting buffers and arrived at a composition designated as the SDS-PAGE-Urea Lysis buffer. The use of this buffer and specific conditions allowed the reproducible transfer of highly hydrophobic bacterial membrane proteins with 2-12 transmembrane-spanning segments as well as soluble proteins onto nitrocellulose membranes. This method should be broadly applicable for immunochemical studies of other membrane proteins.

Measurement of subcooled boiling pressure drop and local heat transfer coefficient in horizontal tube under LPLF conditions

International Nuclear Information System (INIS)

Baburajan, P.K.; Bisht, G.S.; Gupta, S.K.; Prabhu, S.V.

2013-01-01

Highlights: ► Measured subcooled boiling pressure drop and local heat transfer coefficient in horizontal tubes. ► Infra-red thermal imaging is used for wall temperature measurement. ► Developed correlations for pressure drop and local heat transfer coefficient. -- Abstract: Horizontal flow is commonly encountered in boiler tubes, refrigerating equipments and nuclear reactor fuel channels of pressurized heavy water reactors (PHWR). Study of horizontal flow under low pressure and low flow (LPLF) conditions is important in understanding the nuclear core behavior during situations like LOCA (loss of coolant accidents). In the present work, local heat transfer coefficient and pressure drop are measured in a horizontal tube under LPLF conditions of subcooled boiling. Geometrical parameters covered in this study are diameter (5.5 mm, 7.5 mm and 9.5 mm) and length (550 mm, 750 mm and 1000 mm). The operating parameters varied are mass flux (450–935 kg/m 2 s) and inlet subcooling (29 °C, 50 °C and 70 °C). Infra-red thermography is used for the measurement of local wall temperature to estimate the heat transfer coefficient in single phase and two phase flows with water as the working medium at atmospheric pressure. Correlation for single phase diabatic pressure drop ratio (diabatic to adiabatic) as a function of viscosity ratio (wall temperature to fluid temperature) is presented. Correlation for pressure drop under subcooled boiling conditions as a function of Boiling number (Bo) and Jakob number (Ja) is obtained. Correlation for single phase heat transfer coefficient in the thermal developing region is presented as a function of Reynolds number (Re), Prandtl number (Pr) and z/d (ratio of axial length of the test section to diameter). Correlation for two phase heat transfer coefficient under subcooled boiling condition is developed as a function of boiling number (Bo), Jakob number (Ja) and Prandtl number (Pr)

Improving conditions for transferring family enterprises in Estonia. Pereettevõtte üleandmise võimalustest Eestis

Directory of Open Access Journals (Sweden)

Maret Güldenkoh

2014-12-01

Full Text Available Family enterprise is a business entity that belongs to the family. In Estonia the concept of family business, family entrepreneur, or family enterprise has not been defined in legislation. The concepts of business and enterprise have been defined in several pieces of law with some dissensions in their interpretations, however. Differences in legal definitions become obvious when transferring a business. The aim of the article is to assess the legislative conditions of family enterprises in Estonia. Family enterprises can be transferred either by way of transferring the holding status or by transferring the enterprise. Holding can be transferred in companies; a sole proprietor should transfer the business entity either as a whole or transfer the business entity into a company to have a holding there. Family businesses operating as sole proprietors may incur tax liability by transferring the family enterprise. The paper outlines special features of transferring enterprises, including family enterprises in Estonia. Business transfers have been few and there is no unambiguous practice in this sphere. Transfer of family enterprises is identified with transfer of enterprises; differences arise when family business has been registered as a sole proprietor. The paper provides a brief description of the differences in transferring enterprises, including family enterprises in Estonia. A purpose was to evaluate the legal environment of transferring family enterprises. In Estonia guidelines should be formulated for transferring the business of a self-employed family member and legal regulations should be introduced to avoid ill-intentioned transfer of enterprises.

Feed tank transfer requirements

Energy Technology Data Exchange (ETDEWEB)

Freeman-Pollard, J.R.

1998-09-16

This document presents a definition of tank turnover. Also, DOE and PC responsibilities; TWRS DST permitting requirements; TWRS Authorization Basis (AB) requirements; TWRS AP Tank Farm operational requirements; unreviewed safety question (USQ) requirements are presented for two cases (i.e., tank modifications occurring before tank turnover and tank modification occurring after tank turnover). Finally, records and reporting requirements, and documentation which will require revision in support of transferring a DST in AP Tank Farm to a privatization contractor are presented.

Feed tank transfer requirements

International Nuclear Information System (INIS)

Freeman-Pollard, J.R.

1998-01-01

This document presents a definition of tank turnover. Also, DOE and PC responsibilities; TWRS DST permitting requirements; TWRS Authorization Basis (AB) requirements; TWRS AP Tank Farm operational requirements; unreviewed safety question (USQ) requirements are presented for two cases (i.e., tank modifications occurring before tank turnover and tank modification occurring after tank turnover). Finally, records and reporting requirements, and documentation which will require revision in support of transferring a DST in AP Tank Farm to a privatization contractor are presented

Effects of partial slip boundary condition and radiation on the heat and mass transfer of MHD-nanofluid flow

Science.gov (United States)

Abd Elazem, Nader Y.; Ebaid, Abdelhalim

2017-12-01

In this paper, the effect of partial slip boundary condition on the heat and mass transfer of the Cu-water and Ag-water nanofluids over a stretching sheet in the presence of magnetic field and radiation. Such partial slip boundary condition has attracted much attention due to its wide applications in industry and chemical engineering. The flow is basically governing by a system of partial differential equations which are reduced to a system of ordinary differential equations. This system has been exactly solved, where exact analytical expression has been obtained for the fluid velocity in terms of exponential function, while the temperature distribution, and the nanoparticles concentration are expressed in terms of the generalized incomplete gamma function. In addition, explicit formulae are also derived from the rates of heat transfer and mass transfer. The effects of the permanent parameters on the skin friction, heat transfer coefficient, rate of mass transfer, velocity, the temperature profile, and concentration profile have been discussed through tables and graphs.

In vitro base modification of Escherichia coli glutamate 2 transfer-RNA and phenylalanine transfer-RNA gene transcripts

International Nuclear Information System (INIS)

Shahan, M.N.

1989-01-01

Plasmids were constructed that contain an E. Coli tRNA 2 Glu or tRNA Phe gene in a system transcribable by T7 or SP6 RNA polymerase. Selectively 32 P-labeled transcripts of these plasmids were used to study tRNA base modification in vitro in crude extracts by nearest neighbor analysis. The synthesis of 5-methyl-aminomethyl-2-thiouridine (mnm 5 s 2 U) was studied. Complete synthesis of mnm 5 s 2 2U is not observed. Instead, 2-thiouridine (s 2 U) is synthesized. Synthesis requires ATP, cysteine, Mg + , and monovalent cation concentrations below 50 mM. The reaction has a pH optimum above 7.0. Sulfide ion will substitute for cysteine in the reaction but sulfate, sulfite, methionine, homocysteine, and β-mercaptopyruvate will not. Extracts from E. coli strains carrying either the asuE or asuF mutations have reduced s 2 U synthetic activity which supports in vivo evidence that the wild type genes are involved in 2-thiolation of uridine. The enzyme is shown to be unstable both upon storage at -80 degree C and during the modification reaction. A method was developed to study the synthesis of any one of four pseudouridines ψ found at different positions of the tRNA cloverleaf. Synthesis of ψ is observed at three of the four positions-positions 32, 39, and 55. The asuC mutation is shown to affect ψ synthesis only at position 39 confirming that it is an allele of hisT and that the hisT mutations do not affect ψ synthesis at position 32 in E. coli. Synthesis of ψ32, ψ39, and ψ55 does not require any prior modification. Synthesis of dihydrouridine, 7-methylguanosine, and 3(3-amino-3-carboxypropyl)uridine is also observed. Synthesis of 2-methyladenosine and ψ 13 is not seen. Removal of part of the aminoacyl stem reduces synthesis of all modifications examined by 3' fold or more

Review and proposal for heat transfer predictions at supercritical water conditions using existing correlations and experiments

Energy Technology Data Exchange (ETDEWEB)

Jaeger, Wadim, E-mail: wadim.jaeger@kit.edu [Karlsruhe Institute of Technology, Institute for Neutron Physics and Reactor Technology, DE-76344 Eggenstein-Leopoldshafen (Germany); Sanchez Espinoza, Victor Hugo [Karlsruhe Institute of Technology, Institute for Neutron Physics and Reactor Technology, DE-76344 Eggenstein-Leopoldshafen (Germany); Hurtado, Antonio [Technical University of Dresden, Institute of Power Engineering, DE-01062 Dresden (Germany)

2011-06-15

Highlights: > Implementation of heat transfer correlations for supercritical water into TRACE. > Simulation of several heat transfer experiments with modified TRACE version. > Most correlations are not able to reproduce the experimental results. > Bishop, Sandberg and Tong correlation is most suitable for TRACE applications. - Abstract: This paper summarizes the activities of the TRACE code validation at the Institute for Neutron Physics and Reactor Technology related to supercritical water conditions. In particular, the providing of the thermo physical properties and its appropriate use in the wall-to-fluid heat transfer models in the frame of the TRACE code is the object of this investigation. In a first step, the thermo physical properties of the original TRACE code were modified in order to account for supercritical conditions. In a second step, existing Nusselt correlations were reviewed and implemented into TRACE and available experiments were simulated to identify the most suitable Nusselt correlation(s).

Conditional transfer of emission rights. Not a good idea; Voorwaardelijke overdraagbaarheid emissierechten. Geen goede gedachte

Energy Technology Data Exchange (ETDEWEB)

Van Engelen, Th.C.J.A. [Clifford Chance LLP, Amsterdam (Netherlands)

2004-02-01

The Dutch government embraces the idea that trading of emission allowances is a useful way of reducing the emission of harmful gasses. In the current plans to amend the Environmental Management Act, however, the legislator has chosen for a system where allowances may only be transferred in accordance with strict conditions. These conditions do not provide a legal framework for an efficient emission allowances trading market. As a result, Dutch industry will potentially be placed in an unfavourable position. The legislator, it is suggested, should opt for fully transferable allowances. It is crucial that an efficient international market for trading in allowances is established. This means that it should be possible to trade these allowances easily, without excessive legal restrictions. The aim of the legislator is to prevent extreme situations in this market. While its concerns are valid, however, the legislator has missed the mark by choosing a system whereby transfer of allowances is subject to excessive conditions. The legal consequence of not fulfilling one or more of the conditions during the sale is that the allowance will not be legally transferred, and the seller will remain the proprietor of the allowance, without either the seller or the buyer being aware of the situation. It is clear that this would be an unworkable situation as it would not be possible from a practical angle to simply and quickly check previous transactions. Overall, this would result in high transactions costs, which in turn would be a barrier to an efficient market. In summary, an efficient market in emission allowances seems to be an illusion if the transfer of allowances are subject to such conditions as are presently envisaged by the law. It is suggested that the legislator can reach its goals by dropping the conditions for transfers and by supervising the transactions through administrative and criminal procedures instead. This will not affect the owners-hip of emission allowances

Gaussian variable neighborhood search for the file transfer scheduling problem

Directory of Open Access Journals (Sweden)

Dražić Zorica

2016-01-01

Full Text Available This paper presents new modifications of Variable Neighborhood Search approach for solving the file transfer scheduling problem. To obtain better solutions in a small neighborhood of a current solution, we implement two new local search procedures. As Gaussian Variable Neighborhood Search showed promising results when solving continuous optimization problems, its implementation in solving the discrete file transfer scheduling problem is also presented. In order to apply this continuous optimization method to solve the discrete problem, mapping of uncountable set of feasible solutions into a finite set is performed. Both local search modifications gave better results for the large size instances, as well as better average performance for medium and large size instances. One local search modification achieved significant acceleration of the algorithm. The numerical experiments showed that the results obtained by Gaussian modifications are comparable with the results obtained by standard VNS based algorithms, developed for combinatorial optimization. In some cases Gaussian modifications gave even better results. [Projekat Ministarstava nauke Republike Srbije, br. 174010

Numerical Simulation of Transient Moisture Transfer into an Electronic Enclosure

DEFF Research Database (Denmark)

Shojaee Nasirabadi, Parizad; Jabbaribehnam, Mirmasoud; Hattel, Jesper Henri

2016-01-01

Electronic systems are sometimes exposed to harsh environmental conditions of temperature and humidity. Moisturetransfer into electronic enclosures and condensation can cause several problems such as corrosion and alteration in thermalstresses. It is therefore essential to study the local climate...... inside the enclosures to be able to protect the electronic systems.In this work, moisture transfer into a typical electronic enclosure is numerically studied using CFD. In order to reduce theCPU-time and make a way for subsequent factorial design analysis, a simplifying modification is applied in which...

76 FR 43892 - Modifications of Certain Derivative Contracts

Science.gov (United States)

2011-07-22

... obligations under the derivative contract and the party to which the rights and obligations are transferred or... assigning its rights and obligations under the contract and the party to which the rights and obligations... Modifications of Certain Derivative Contracts AGENCY: Internal Revenue Service (IRS), Treasury. ACTION: Final...

Tungsten-based nanomaterials (WO{sub 3} & Bi{sub 2}WO{sub 6}): Modifications related to charge carrier transfer mechanisms and photocatalytic applications

Energy Technology Data Exchange (ETDEWEB)

Girish Kumar, S., E-mail: girichem@yahoo.co.in; Koteswara Rao, K.S.R., E-mail: raoksrk@gmail.com

2015-11-15

Graphical abstract: - Highlights: • Photocatalytic applications of WO{sub 3} and Bi{sub 2}WO{sub 6} based nanomaterial are reviewed. • Modifications to improve their performance are highlighted. • Charge carrier generation–separation–recombination is discussed. • Challenges and future prospects in this area are addressed. - Abstract: Heterogeneous photocatalysis is an ideal green energy technology for the purification of wastewater. Although titania dominates as the reference photocatalyst, its wide band gap is a bottleneck for extended utility. Thus, search for non-TiO{sub 2} based nanomaterials has become an active area of research in recent years. In this regard, visible light absorbing polycrystalline WO{sub 3} (2.4–2.8 eV) and Bi{sub 2}WO{sub 6} (2.8 eV) with versatile structure-electronic properties has gained considerable interest to promote the photocatalytic reactions. These materials are also explored in selective functional group transformation in organic reactions, because of low reduction and oxidation potential of WO{sub 3} CB and Bi{sub 2}WO{sub 6} VB, respectively. In this focused review, various strategies such as foreign ion doping, noble metal deposition and heterostructuring with other semiconductors designed for efficient photocatalysis is discussed. These modifications not only extend the optical response to longer wavelengths, but also prolong the life-time of the charge carriers and strengthen the photocatalyst stability. The changes in the surface-bulk properties and the charge carrier transfer dynamics associated with each modification correlating to the high activity are emphasized. The presence of oxidizing agents, surface modification with Cu{sup 2+} ions and synthesis of exposed facets to promote the degradation rate is highlighted. In depth study on these nanomaterials is likely to sustain interest in wastewater remediation and envisaged to signify in various green energy applications.

New York City's First Conditional Cash Transfer Program: What Worked, What Didn't

Science.gov (United States)

Riccio, James; Miller, Cynthia

2016-01-01

This report summarizes the findings of a long-term evaluation of Opportunity NYC--Family Rewards, an experimental, privately funded, conditional cash transfer (CCT) program to help families break the cycle of poverty. Family Rewards was the first comprehensive CCT program in a developed country. Launched in 2007 by New York City's Center for…

Modification and validation of the natural heat convection and subcooled void formation models in the code PARET

International Nuclear Information System (INIS)

Hainoun, A.; Alhabit, F.; Ghazi, N.

2008-01-01

Two new modifications have been included in the current PARET code that is widely applied in the dynamic and safety analysis of research reactors. A new model was implemented for the simulation of void formation in the subcooled boiling regime, the other modification dealt with the implementation of a new approach to improve the prediction of heat transfer coefficient under natural circulation condition. The modified code was successfully validated using adequate single effect tests covering the physical phenomena of interest for both natural circulation and subcooled void formation at low pressure and low heat flux. The validation results indicate significant improvement of the code compared to the default version. Additionally, to simplify the code application an interactive user interface was developed enabling pre and post-processing of the code predictions. (author)

Review and proposal for heat transfer predictions at supercritical water conditions using existing correlations and experiments

International Nuclear Information System (INIS)

Jaeger, Wadim; Sanchez Espinoza, Victor Hugo; Hurtado, Antonio

2011-01-01

Highlights: → Implementation of heat transfer correlations for supercritical water into TRACE. → Simulation of several heat transfer experiments with modified TRACE version. → Most correlations are not able to reproduce the experimental results. → Bishop, Sandberg and Tong correlation is most suitable for TRACE applications. - Abstract: This paper summarizes the activities of the TRACE code validation at the Institute for Neutron Physics and Reactor Technology related to supercritical water conditions. In particular, the providing of the thermo physical properties and its appropriate use in the wall-to-fluid heat transfer models in the frame of the TRACE code is the object of this investigation. In a first step, the thermo physical properties of the original TRACE code were modified in order to account for supercritical conditions. In a second step, existing Nusselt correlations were reviewed and implemented into TRACE and available experiments were simulated to identify the most suitable Nusselt correlation(s).

Conditional cash transfers and social welfare. A look into two Latin American case studies

Directory of Open Access Journals (Sweden)

Alexia Delclaux Gaytán de Ayala

2015-12-01

Full Text Available This paper analyses the role of conditional cash transfers (CCT in improving social indicators during the past decade in Brazil and Peru. Barely two decades after the appearance of the first programmes, CCTs – cash transfers to families living in poverty or extreme poverty conditioned to school attendance and compulsory medical visits for children – are now one of the main policy tools in the fight against poverty in dozens of developing countries. More specifically, this paper examines the link between the CCT programme in each of these two countries – the giant Bolsa Familia in Brazil, the pioneer and largest program of this type in the world, and Juntos in Peru, smaller in terms of size and relevance, but practically identical in its design – and the evolution of social indicators relative to poverty, education and health.

Transfer phenomena in p-PbTe monocrystals grown under zero-g conditions

International Nuclear Information System (INIS)

Regel', L.L.; Rakhmatov, O.I.; Red'ko, N.A.; Parfen'ev, R.V.; AN SSSR, Leningrad. Fiziko-Tekhnicheskij Inst.)

1984-01-01

The purpose of the study is comparative investigation of low-temperature phenomena of charge and heat transfer in p-PbTe monocrystals grown by the method of oriented crystallization under zero-g conditions as well as under terrestrial conditions at identical technological regimes. Investigation of thermal conductivity a strong magnetic field permits to separate lattice and electron thermal conductivity components, the latter constituting 6% of total thermal conductivity. Therefore the predominant contribution to kappa(T) is made by the lattice thermal conductivity which turned to be close by value for both samples. This points to identical character of structural perfection of p-PbTe investigated monocrystals

Heat Transfer Enhancement of the Air-Cooling Tower with Rotating Wind Deflectors under Crosswind Conditions

OpenAIRE

Xueping Du; Dongtai Han; Qiangmin Zhu

2018-01-01

To investigate the effect of wind deflectors on air flow and heat transfer performance of an air-cooling tower under crosswind conditions, an experimental system based on a surface condenser aluminum exchanger-type indirect air-cooling tower is established at a 1:100 proportional reduction. A 3-D computational fluid dynamics simulation model is built to study the air flow and temperature fields. The air flow rate into the cooling tower and the heat transfer rate of the radiators are used to e...

Condition monitoring of steam generator by estimating the overall heat transfer coefficient

International Nuclear Information System (INIS)

Furusawa, Hiroaki; Gofuku, Akio

2013-01-01

This study develops a technique for monitoring in on-line the state of the steam generator of the fast-breeder reactor (FBR) “Monju”. Because the FBR uses liquid sodium as coolant, it is necessary to handle liquid sodium with caution due to its chemical characteristics. The steam generator generates steam by the heat of secondary sodium coolant. The sodium-water reaction may happen if a pinhole or crack occurs at the thin metal tube wall that separates the secondary sodium coolant and water/steam. Therefore, it is very important to detect an anomaly of the wall of heat transfer tubes at an early stage. This study aims at developing an on-line condition monitoring technique of the steam generator by estimating overall heat transfer coefficient from process signals. This paper describes simplified mathematical models of superheater and evaporator to estimate the overall heat transfer coefficient and a technique to diagnose the state of the steam generator. The applicability of the technique is confirmed by several estimations using simulated process signals with artificial noises. The results of the estimations show that the developed technique can detect the occurrence of an anomaly. (author)

Heat and mass transfer boundary conditions at the surface of a heated sessile droplet

Science.gov (United States)

Ljung, Anna-Lena; Lundström, T. Staffan

2017-12-01

This work numerically investigates how the boundary conditions of a heated sessile water droplet should be defined in order to include effects of both ambient and internal flow. Significance of water vapor, Marangoni convection, separate simulations of the external and internal flow, and influence of contact angle throughout drying is studied. The quasi-steady simulations are carried out with Computational Fluid Dynamics and conduction, natural convection and Marangoni convection are accounted for inside the droplet. For the studied conditions, a noticeable effect of buoyancy due to evaporation is observed. Hence, the inclusion of moisture increases the maximum velocities in the external flow. Marangoni convection will, in its turn, increase the velocity within the droplet with up to three orders of magnitude. Results furthermore show that the internal and ambient flow can be simulated separately for the conditions studied, and the accuracy is improved if the internal temperature gradient is low, e.g. if Marangoni convection is present. Simultaneous simulations of the domains are however preferred at high plate temperatures if both internal and external flows are dominated by buoyancy and natural convection. The importance of a spatially resolved heat and mass transfer boundary condition is, in its turn, increased if the internal velocity is small or if there is a large variation of the transfer coefficients at the surface. Finally, the results indicate that when the internal convective heat transport is small, a rather constant evaporation rate may be obtained throughout the drying at certain conditions.

Heat Transfer Enhancement of the Air-Cooling Tower with Rotating Wind Deflectors under Crosswind Conditions

Directory of Open Access Journals (Sweden)

Xueping Du

2018-04-01

Full Text Available To investigate the effect of wind deflectors on air flow and heat transfer performance of an air-cooling tower under crosswind conditions, an experimental system based on a surface condenser aluminum exchanger-type indirect air-cooling tower is established at a 1:100 proportional reduction. A 3-D computational fluid dynamics simulation model is built to study the air flow and temperature fields. The air flow rate into the cooling tower and the heat transfer rate of the radiators are used to evaluate cooling performance. Rotating wind deflectors are adopted to reduce the influence of crosswind on the cooling tower performance. The effects of the rotating wind deflectors on the thermal-hydraulic characteristics of the air-cooling tower under different environmental crosswind speeds are studied. Results indicate that the wind direction in the tower reverses as the rotating speed of the wind deflectors increases. The thermal performance of an air-cooling tower under crosswind conditions can be improved by using rotating wind deflectors. The heat transfer rate of a cooling tower with eight wind deflectors begins to increase when the rotating speed exceeds 2 r/min.

Multiple determinants of transfer of evaluative function after conditioning with free-operant schedules of reinforcement.

Science.gov (United States)

Dack, Charlotte; Reed, Phil; McHugh, Louise

2010-11-01

The aim of the four present experiments was to explore how different schedules of reinforcement influence schedule-induced behavior, their impact on evaluative ratings given to conditioned stimuli associated with each schedule through evaluative conditioning, and the transfer of these evaluations through derived stimulus networks. Experiment 1 compared two contrasting response reinforcement rules (variable ratio [VR], variable interval [VI]). Experiment 2 varied the response to reinforcement rule between two schedules but equated the outcome to response rate (differential reinforcement of high rate [DRH] vs. VR). Experiment 3 compared molar and molecular aspects of contingencies of reinforcement (tandem VIVR vs. tandem VRVI). Finally, Experiment 4 employed schedules that induced low rates of responding to determine whether, under these circumstances, responses were more sensitive to the molecular aspects of a schedule (differential reinforcement of low rate [DRL] vs. VI). The findings suggest that the transfer of evaluative functions is determined mainly by differences in response rate between the schedules and the molar aspects of the schedules. However, when neither schedule was based on a strong response reinforcement rule, the transfer of evaluative judgments came under the control of the molecular aspects of the schedule.

Enzymatic modification of starch

DEFF Research Database (Denmark)

Jensen, Susanne Langgård

In the food industry approaches for using bioengineering are investigated as alternatives to conventional chemical and physical starch modification techniques in development of starches with specific properties. Enzyme-assisted post-harvest modification is an interesting approach to this, since...... it is considered a clean and energy saving technology. This thesis aimed to investigate the effect of using reaction conditions, simulating an industrial process, for enzymatic treatment of starch with branching enzyme (BE) from Rhodothermus obamensis. Thus treatements were conducted at 70°C using very high...... substrate concentration (30-40% dry matter (DM)) and high enzyme activity (750-2250 BE units (BEU)/g sample). Starches from various botanical sources, representing a broad range of properties, were used as substrates. The effects of the used conditions on the BE-reaction were evaluated by characterization...

Modification in fuel processing of Mitsubishi Nuclear Fuel's Tokai Works

International Nuclear Information System (INIS)

1976-01-01

Results of the study by the Committee for Examination of Fuel Safety, reported to the AEC of Japan, are presented, concerning safety of the modifications of Tokai Works, Mitsubishi Nuclear Fuel Co., Ltd. Safety has been confirmed thereof. The modifications covered are the following: storage facility of nuclear fuel in increase, analytical facility in transfer, fuel assemblage equipment in addition, incineration facility of combustible solid wastes in installation, experimental facility of uranium recovery in installation, and warehouse in installation. (Mori, K.)

MODIFICATION OF SURFACE KONDENSITSIONNYH AEROSOLS WELDING AND METALLURGICHESKIH PRODUCTIONS

Directory of Open Access Journals (Sweden)

A. A. Ennan

2016-04-01

Full Text Available Chemical modification of surface kondensitsionnyh aerosols (KA which formation when heat treatment metals (process of weld, foundry processes with application chlorosilanes are suggested. Adsorbtion vapor of water on modification powders KA decreases and changes in varies from modifier and conditions modification are setted.

Modification of working conditions based on ergo THK reducing workload, muscle tension, and fatigue of rice milling workers in J village

Science.gov (United States)

Ruliati, L. P.; Adiputra, N.; Sutjana, I. D. P.; Sutajaya, I. M.

2017-11-01

Rice mill is one of the businesses in informal sector. From the rice milling process, ergonomic problems arise when employees work with bent position that done repeatedly to lift grain sacks to be transferred to peeler machine. This situation will affect the comfort of work, thus increasing the workload, muscle tension, and fatigue. The consequence will certainly affect the health and productivity of workers. In this study introduces ergo Tri Hita Karana (ergo THK) as an ergonomics intervention model which solves ergonomics problems of the cultural aspects of THK. The study aim is to determine the modification of working conditions based Ergo THK to reduce workload, muscle tension and fatigue. This research uses Randomized Pretest and Posttest Control Group Design experimental design. The subjects were 30 male rice mill workers with an age range of 16 until 56 years, and then divided into 15 subjects in the control group and 15 subjects in the treatment group. The results showed that the average posttest workloads in the control group are 136.950 more less 0.297 and in the treatment group are 107.60 more less 0.396. Significance analysis showed that after the two groups done their activities, the average workload significantly different p less than 0.005. The amount of reduction in the workload between the two groups was 21.43 percent. In muscle tension posttest showed that the mean score of the muscle tension in the control group was 62.67 more less 7.31 and the treatment group was 20.96 more less 2.96. Significance analysis showed that both groups mean muscle-tension results were significantly different p less than 0.005. The amount of reduction in tension between the control group and the treatment group while working was 66.55 percent. At fatigue posttest showed that the mean score of fatigue in the control group was 76.40 more less 13.51 and the treatment group was 55.53 more less 9.51. Significant analysis showed that the mean fatigue of both groups

Anatomic and physiological modifications in seedlings of Coffea arabica cultivar Siriema under drought conditions

Directory of Open Access Journals (Sweden)

Emanuelle Ferreira Melo

2014-02-01

Full Text Available Due to the weather changes prognostic for the coming years, the understanding of water deficit and physiological responses of plants to drought becomes an important requirement in order to develop technologies such as mechanisms to assist plants to cope with longer drought periods, which will be essential to maintenance of Brazilian and worldwide production. This study aimed to evaluate ecophysiological and anatomical aspects as well as the nitrate reductase activity in Siriema coffee seedlings subjected to four treatments: Daily irrigated, non-irrigated, re-irrigated 24 hours and re-irrigated 48 hours after different stress periods. Non-irrigation promoted a reduction in leaf water potential being accented from the ninth day of evaluation onwards. Re-irrigation promoted a partial recovery of the plant water potential. Non-irrigated plants showed an increase in stomatal resistance and reduction of transpiration and nitrate reductase activity. In the roots, there was a decrease in nitrate reductase activity under water stress. Leaf anatomical modifications were significant only for the adaxial surface epidermis and palisade parenchyma thickness, this latter characteristic being higher in control plants. Stomatal density and polar and equatorial diameter ratios showed the highest values in plants under water stress. In the roots, differences only in the cortex thickness being bigger in the non-irrigated treatment could be observed. Therefore, Siriema coffee plants under water stress show physiological, biochemical and anatomical modifications that contribute to the tolerance of this genotype to these conditions.

Numerical simulation of transient moisture transfer into an electronic enclosure

Energy Technology Data Exchange (ETDEWEB)

Nasirabadi, P. Shojaee; Jabbari, M.; Hattel, J. H. [Process Modelling Group, Department of Mechanical Engineering, Technical University of Denmark, Nils Koppels Allé, 2800 Kgs. Lyngby (Denmark)

2016-06-08

Electronic systems are sometimes exposed to harsh environmental conditions of temperature and humidity. Moisture transfer into electronic enclosures and condensation can cause several problems such as corrosion and alteration in thermal stresses. It is therefore essential to study the local climate inside the enclosures to be able to protect the electronic systems. In this work, moisture transfer into a typical electronic enclosure is numerically studied using CFD. In order to reduce the CPU-time and make a way for subsequent factorial design analysis, a simplifying modification is applied in which the real 3D geometry is approximated by a 2D axial symmetry one. The results for 2D and 3D models were compared in order to calibrate the 2D representation. Furthermore, simulation results were compared with experimental data and good agreement was found.

Numerical simulation of transient moisture transfer into an electronic enclosure

International Nuclear Information System (INIS)

Nasirabadi, P. Shojaee; Jabbari, M.; Hattel, J. H.

2016-01-01

Electronic systems are sometimes exposed to harsh environmental conditions of temperature and humidity. Moisture transfer into electronic enclosures and condensation can cause several problems such as corrosion and alteration in thermal stresses. It is therefore essential to study the local climate inside the enclosures to be able to protect the electronic systems. In this work, moisture transfer into a typical electronic enclosure is numerically studied using CFD. In order to reduce the CPU-time and make a way for subsequent factorial design analysis, a simplifying modification is applied in which the real 3D geometry is approximated by a 2D axial symmetry one. The results for 2D and 3D models were compared in order to calibrate the 2D representation. Furthermore, simulation results were compared with experimental data and good agreement was found.

Optimizing pentacene thin-film transistor performance: Temperature and surface condition induced layer growth modification.

Science.gov (United States)

Lassnig, R; Hollerer, M; Striedinger, B; Fian, A; Stadlober, B; Winkler, A

2015-11-01

In this work we present in situ electrical and surface analytical, as well as ex situ atomic force microscopy (AFM) studies on temperature and surface condition induced pentacene layer growth modifications, leading to the selection of optimized deposition conditions and entailing performance improvements. We prepared p ++ -silicon/silicon dioxide bottom-gate, gold bottom-contact transistor samples and evaluated the pentacene layer growth for three different surface conditions (sputtered, sputtered + carbon and unsputtered + carbon) at sample temperatures during deposition of 200 K, 300 K and 350 K. The AFM investigations focused on the gold contacts, the silicon dioxide channel region and the highly critical transition area. Evaluations of coverage dependent saturation mobilities, threshold voltages and corresponding AFM analysis were able to confirm that the first 3-4 full monolayers contribute to the majority of charge transport within the channel region. At high temperatures and on sputtered surfaces uniform layer formation in the contact-channel transition area is limited by dewetting, leading to the formation of trenches and the partial development of double layer islands within the channel region instead of full wetting layers. By combining the advantages of an initial high temperature deposition (well-ordered islands in the channel) and a subsequent low temperature deposition (continuous film formation for low contact resistance) we were able to prepare very thin (8 ML) pentacene transistors of comparably high mobility.

Development of experimental data bank on heat transfer crisis under stationary conditions

International Nuclear Information System (INIS)

Koshtyalek, Ya.

1982-01-01

The development of an experimental data bank on heat transfer orisis under stationary conditions is discussed. The work is being carried out under the auspices of CMEA in compliance with the resolution of CMEA countries experts meetinq in January 1981 held in Moscow. The data bank is supposed to be formed as a sequential set of available experimental data on the regimes with heat-transfer crisis, recorded on a standard magnetic tape for ES or IBM comuter family. All operations with the bank are to be performed via the computer. Recommendations are given to what the record structure should be used and an example of a code is suggested for a user to extract data from the bank in accordance with various criteria. At the present time parameters of more than 12000 experimental regimes are prepared for the bank and some 3000 more are being processed [ru

Performance analyses of helical coil heat exchangers. The effect of external coil surface modification on heat exchanger effectiveness

Science.gov (United States)

Andrzejczyk, Rafał; Muszyński, Tomasz

2016-12-01

The shell and coil heat exchangers are commonly used in heating, ventilation, nuclear industry, process plant, heat recovery and air conditioning systems. This type of recuperators benefits from simple construction, the low value of pressure drops and high heat transfer. In helical coil, centrifugal force is acting on the moving fluid due to the curvature of the tube results in the development. It has been long recognized that the heat transfer in the helical tube is much better than in the straight ones because of the occurrence of secondary flow in planes normal to the main flow inside the helical structure. Helical tubes show good performance in heat transfer enhancement, while the uniform curvature of spiral structure is inconvenient in pipe installation in heat exchangers. Authors have presented their own construction of shell and tube heat exchanger with intensified heat transfer. The purpose of this article is to assess the influence of the surface modification over the performance coefficient and effectiveness. The experiments have been performed for the steady-state heat transfer. Experimental data points were gathered for both laminar and turbulent flow, both for co current- and countercurrent flow arrangement. To find optimal heat transfer intensification on the shell-side authors applied the number of transfer units analysis.

Controlling resonance energy transfer in nanostructure emitters by positioning near a mirror

Science.gov (United States)

Weeraddana, Dilusha; Premaratne, Malin; Gunapala, Sarath D.; Andrews, David L.

2017-08-01

The ability to control light-matter interactions in quantum objects opens up many avenues for new applications. We look at this issue within a fully quantized framework using a fundamental theory to describe mirror-assisted resonance energy transfer (RET) in nanostructures. The process of RET communicates electronic excitation between suitably disposed donor and acceptor particles in close proximity, activated by the initial excitation of the donor. Here, we demonstrate that the energy transfer rate can be significantly controlled by careful positioning of the RET emitters near a mirror. The results deliver equations that elicit new insights into the associated modification of virtual photon behavior, based on the quantum nature of light. In particular, our results indicate that energy transfer efficiency in nanostructures can be explicitly expedited or suppressed by a suitably positioned neighboring mirror, depending on the relative spacing and the dimensionality of the nanostructure. Interestingly, the resonance energy transfer between emitters is observed to "switch off" abruptly under suitable conditions of the RET system. This allows one to quantitatively control RET systems in a new way.

Microcomputer based program for predicting heat transfer under reactor accident conditions. Volume I

International Nuclear Information System (INIS)

Cheng, S.C.; Groeneveld, D.C.; Leung, L.K.H.; Wong, Y.L.; Nguyen, C.

1987-07-01

A microcomputer based program called Heat Transfer Prediction Software (HTPS) has been developed. It calculates the heat transfer for the tube and bundle geometries for steady state and transient conditions. This program is capable of providing the best estimated of the hot pin temperatures during slow transients for 37- and 28-element CANDU type fuel bundles. The program is designed for an IBM-PC AT/XT (or IBM-PC compatible computer) equipped with a Math Co-processor. The following input parameters are required: pressure, mass flux, hydraulic diameter, and quality. For the steady state case, the critical heat flux (CHF), the critical heat flux temperature, the minimum film boiling temperature, and the minimum film boiling heat flux are the primary outputs. With either the surface heat flux or wall temperature specified, the program determines the heat transfer regime and calculates the surface heat flux, wall temperatures and heat transfer coefficient. For the slow transient case, the pressure, mass flux, quality, and volumetric heat generation rate are the time dependent input parameters required to calculate the hot pin sheath temperatures and surface heat fluxes. A simple routine for generating properties has been developed for light water to support the above program. It contains correlations that have been verified for pressures ranging from 0.6kPa to 30 MPa, and temperatures up to 1100 degrees Celcius. The thermodynamic and transport properties that can be generated from this routine are: density, specific volume, enthalpy, specific heat capacity, conductivity, viscosity, surface tension and Prandtl number for saturated liquid, saturated vapour, subcooled liquid for superheated vapour. A software for predicting flow regime has also been developed. It determines the flow pattern at specific flow conditions, and provides a correction factor for calculating the CHF during partially stratified horizontal flow. The technical bases for the program and its

Microcomputer based program for predicting heat transfer under reactor accident conditions. Volume II

International Nuclear Information System (INIS)

Cheng, S.C.; Groeneveld, D.C.; Leung, L.K.H.; Wong, Y.L.; Nguyen, C.

1987-07-01

A microcomputer based program called Heat Transfer Prediction Software (HTPS) has been developed. It calculates the heat transfer for tube and bundle geometries for steady state and transient conditions. This program is capable of providing the best estimated of the hot pin temperatures during slow transients for 37- and 28-element CANDU type fuel bundles. The program is designed for an IBM-PC AT/XT (or IBM-PC compatible computer) equipped with a Math Co-processor. The following input parameters are required: pressure, mass flux, hydraulic diameter, and quality. For the steady state case, the critical heat flux (CHF), the critical heat flux temperature, the minimum film boiling temperature, and the minimum film boiling heat flux are the primary outputs. With either the surface heat flux or wall temperature specified, the program determines the heat transfer regime and calculates the surface heat flux, wall temperature and heat transfer coefficient. For the slow transient case, the pressure, mass flux, quality, and volumetric heat generation rate are the time dependent input parameters are required to calculate the hot pin sheath temperatures and surface heat fluxes. A simple routine for generating properties has been developed for light water to support the above program. It contains correlations that have been verified for pressures ranging from 0.6kPa to 30 MPa, and temperatures up to 1100 degrees Celcius. The thermodynamic and transport properties that can be generated from this routine are: density, specific volume, enthalpy, specific heat capacity, conductivity, viscosity, surface tension and Prandtle number for saturated liquid, saturated vapour, subcooled liquid of superheated vapour. A software for predicting flow regime has also been developed. It determines the flow pattern at specific flow conditions, and provides a correction factor for calculating the CHF during partially stratified horizontal flow. The technical bases for the program and its structure

Genetic modification of adeno-associated viral vector type 2 capsid enhances gene transfer efficiency in polarized human airway epithelial cells.

Science.gov (United States)

White, April F; Mazur, Marina; Sorscher, Eric J; Zinn, Kurt R; Ponnazhagan, Selvarangan

2008-12-01

Cystic fibrosis (CF) is a common genetic disease characterized by defects in the expression of the CF transmembrane conductance regulator (CFTR) gene. Gene therapy offers better hope for the treatment of CF. Adeno-associated viral (AAV) vectors are capable of stable expression with low immunogenicity. Despite their potential in CF gene therapy, gene transfer efficiency by AAV is limited because of pathophysiological barriers in these patients. Although a few AAV serotypes have shown better transduction compared with the AAV2-based vectors, gene transfer efficiency in human airway epithelium has still not reached therapeutic levels. To engineer better AAV vectors for enhanced gene delivery in human airway epithelium, we developed and characterized mutant AAV vectors by genetic capsid modification, modeling the well-characterized AAV2 serotype. We genetically incorporated putative high-affinity peptide ligands to human airway epithelium on the GH loop region of AAV2 capsid protein. Six independent mutant AAV were constructed, containing peptide ligands previously reported to bind with high affinity for known and unknown receptors on human airway epithelial cells. The vectors were tested on nonairway cells and nonpolarized and polarized human airway epithelial cells for enhanced infectivity. One of the mutant vectors, with the peptide sequence THALWHT, not only showed the highest transduction in undifferentiated human airway epithelial cells but also indicated significant transduction in polarized cells. Interestingly, this modified vector was also able to infect cells independently of the heparan sulfate proteoglycan receptor. Incorporation of this ligand on other AAV serotypes, which have shown improved gene transfer efficiency in the human airway epithelium, may enhance the application of AAV vectors in CF gene therapy.

Emergency transfer tube closure and process for sealing transfer tube under emergency conditions

International Nuclear Information System (INIS)

Hardin, R.T. Jr.; Marshall, J.R.

1987-01-01

In a nuclear fuel reactor well that includes a transfer tube projecting outwardly from wall thereof, the transfer tube is described having a first closure assembly. The transfer tube has a circumferential flange extending outwardly laterally therefrom, an emergency transfer tube closure therefor comprising; a pair of elongated, vertically-extending U-shaped guides, one U-shaped guide disposed laterally on each side of the transfer tube, each of the U-shaped guides comprising a base and laterally extending flanges thereon, the U-shaped guides having their open ends facing each other, a closure plate, having a surface facing the circumferential flange greater in area than the area circumscribed by the outer circumference of the circumferential flange, vertically disposed the U-shaped guides, the closure plate normally being disposed in a vertical plane just slightly in front of the vertical plane of the circumferential flange, two pairs of rollers, one pair of which is rotatably mounted on each side of the closure plate adjacent the U-shaped guides, riding on the inner portion of each of the flanges of each of the U-shaped guides. Each of the U-shaped guides is provided with a pair of spatially disposed openings on a flange thereof adjacent the wall of the nuclear fuel reactor well, each of the pairs of openings being disposed on each of the U-shaped guides a distance equal to the distance between the center lines of the corresponding pair of rollers riding within the U-shaped guides, each of the openings being sufficiently large to receive a corresponding roller of the pairs of rollers in the U-shaped guides. The openings is shaped on the flanges of the U-shaped guides so that when the pairs of rollers are disposed therein, the face of the closure plate will be in sealing engagement with the circumferential flange of the transfer tube

Heat transfer augmentation in a tube using nanofluids under constant heat flux boundary condition: A review

International Nuclear Information System (INIS)

Singh, Vinay; Gupta, Munish

2016-01-01

Highlights: • Reviews heat transfer augmentation of nanofluids in a tube with constant heat flux. • Recent advances in hybrid nanofluids are reviewed. • Identifies and compares significant results. • Scope of future research in this area is discussed. - Abstract: In the last few decades, research on nanofluids has increased rapidly. Traditional heat transfer fluids with order of nanometer sized particles (1–100 nm) suspended in them are termed as nanofluids. Nanofluids have been proved as better heat transfer fluids despite of various contradictions in results by different research groups. The aim of this article is to review and summarize the recent experimental and theoretical studies on convective heat transfer in heat exchangers using constant heat flux boundary condition. The use of different types of nanoparticles with different base fluids by different research groups has been presented and compared. Further an overview of experimental results about heat transfer abilities of hybrid nanofluids from available literature sources is also presented. Finally, the challenges and future directions in which research can be further progress are discussed.

Disrupting astrocyte–neuron lactate transfer persistently reduces conditioned responses to cocaine

KAUST Repository

Boury-Jamot, B

2015-10-27

A central problem in the treatment of drug addiction is the high risk of relapse often precipitated by drug-associated cues. The transfer of glycogen-derived lactate from astrocytes to neurons is required for long-term memory. Whereas blockade of drug memory reconsolidation represents a potential therapeutic strategy, the role of astrocyte–neuron lactate transport in long-term conditioning has received little attention. By infusing an inhibitor of glycogen phosphorylase into the basolateral amygdala of rats, we report that disruption of astrocyte-derived lactate not only transiently impaired the acquisition of a cocaine-induced conditioned place preference but also persistently disrupted an established conditioning. The drug memory was rescued by L-Lactate co-administration through a mechanism requiring the synaptic plasticity-related transcription factor Zif268 and extracellular signal-regulated kinase (ERK) signalling pathway but not the brain-derived neurotrophic factor (Bdnf). The long-term amnesia induced by glycogenolysis inhibition and the concomitant decreased expression of phospho-ERK were both restored with L-Lactate co-administration. These findings reveal a critical role for astrocyte-derived lactate in positive memory formation and highlight a novel amygdala-dependent reconsolidation process, whose disruption may offer a novel therapeutic target to reduce the long-lasting conditioned responses to cocaine.

Disrupting astrocyte–neuron lactate transfer persistently reduces conditioned responses to cocaine

KAUST Repository

Boury-Jamot, B; Carrard, A; Martin, J L; Halfon, O; Magistretti, Pierre J.; Boutrel, B

2015-01-01

A central problem in the treatment of drug addiction is the high risk of relapse often precipitated by drug-associated cues. The transfer of glycogen-derived lactate from astrocytes to neurons is required for long-term memory. Whereas blockade of drug memory reconsolidation represents a potential therapeutic strategy, the role of astrocyte–neuron lactate transport in long-term conditioning has received little attention. By infusing an inhibitor of glycogen phosphorylase into the basolateral amygdala of rats, we report that disruption of astrocyte-derived lactate not only transiently impaired the acquisition of a cocaine-induced conditioned place preference but also persistently disrupted an established conditioning. The drug memory was rescued by L-Lactate co-administration through a mechanism requiring the synaptic plasticity-related transcription factor Zif268 and extracellular signal-regulated kinase (ERK) signalling pathway but not the brain-derived neurotrophic factor (Bdnf). The long-term amnesia induced by glycogenolysis inhibition and the concomitant decreased expression of phospho-ERK were both restored with L-Lactate co-administration. These findings reveal a critical role for astrocyte-derived lactate in positive memory formation and highlight a novel amygdala-dependent reconsolidation process, whose disruption may offer a novel therapeutic target to reduce the long-lasting conditioned responses to cocaine.

Host Specificity of Salmonella typhimurium Deoxyribonucleic Acid Restriction and Modification

Science.gov (United States)

Slocum, Harvey; Boyer, Herbert W.

1973-01-01

The restriction and modification genes of Salmonella typhimurium which lie near the thr locus were transferred to a restrictionless mutant of Escherichia coli. These genes were found to be allelic to the E. coli K, B, and A restriction and modification genes. E. coli recombinants with the restriction and modification host specificity of S. typhimurium restricted phage λ that had been modified by each of the seven known host specificities of E. coli at efficiency of plating levels of about 10−2. Phage λ modified with the S. typhimurium host specificity was restricted by six of the seven E. coli host specificities but not by the RII (fi− R-factor controlled) host specificity. It is proposed that the restriction and modification enzymes of this S. typhimurium host specificity have two substrates, one of which is a substrate for the RII host specificity enzymes. PMID:4570605

Climate policy in developing countries and conditional transfers

International Nuclear Information System (INIS)

Ruebbelke, Dirk T.G.

2006-01-01

This paper analyzes the role international transfers may play in international climate policy in consideration of the policy's ancillary benefits, such as air quality improvements. Ancillary benefits are especially important in many developing countries, while climate protection benefits or primary benefits play a minor role on the political agenda of these countries. In contrast, industrialized countries have a strong interest in combating climate change. These often neglected asymmetries between the developing and industrialized world affect the impacts of transfers. Interestingly, as we will show, the cost differentials between different environmental technologies among countries are the crucial prerequisite for the functioning of a transfer scheme and not the cost differentials in the execution of climate policy. This result has been overlooked by standard pure public good approaches

A matheuristic for transfer synchronization through integrated timetabling and vehicle scheduling

NARCIS (Netherlands)

Roberti, R.

2018-01-01

Long transfer times often add unnecessary inconvenience to journeys in public transport systems. Synchronizing relevant arrival and departure times through small timetable modifications could reduce excess transfer times, but may also directly affect the operational costs, as the timetable defines

Heat transfer characteristics of horizontal steam generators under natural circulation conditions

International Nuclear Information System (INIS)

Hyvaerinen, J.

1996-01-01

This paper deals with the heat transfer characteristics of horizontal steam generators, particularly under natural circulation (decay heat removal) conditions on the primary side. Special emphasis is on the inherent features of horizontal steam generator behaviour. A mathematical model of the horizontal steam generator primary side is developed and qualitative results are obtained analytically. A computer code, called HSG, is developed to solve the model numerically, and its predictions are compared with experimental data. The code is employed to obtain for VVER 440 steam generators quantitative results concerning the dependence of primary-to-secondary heat transfer efficiency on the primary side flow rate, temperature and secondary level. It turns out that the depletion of the secondary inventory leads to an inherent limitation of the decay energy removal in VVER steam generators. The limitation arises as a consequence of the steam generator tube bundle geometry. As an example, it is shown that the grace period associated with pressurizer safety valve opening during a station black-out is 2 1/2-3 hours instead of the 5-6 hours reported in several earlier studies. (However, the change in core heat-up timing is much less-about 1 h at most.) The heat transfer limitation explains the fact that, in the Greifswald VVER 440 station black-out accident in 1975, the steam generators never boiled dry. In addition, the stability of single-phase natural circulation is discussed and insights on the modelling of horizontal steam generators with general-purpose thermal-hydraulic system codes are also presented. (orig.)

Disparity modifications and the emotional effects of stereoscopic images

Science.gov (United States)

Kawai, Takashi; Atsuta, Daiki; Tomiyama, Yuya; Kim, Sanghyun; Morikawa, Hiroyuki; Mitsuya, Reiko; Häkkinen, Jukka

2014-03-01

This paper describes a study that focuses on disparity changes in emotional scenes of stereoscopic (3D) images, in which an examination of the effects on pleasant and arousal was carried out by adding binocular disparity to 2D images that evoke specific emotions, and applying disparity modification based on the disparity analysis of famous 3D movies. From the results of the experiment, for pleasant, a significant difference was found only for the main effect of the emotions. On the other hand, for arousal, there was a trend of increasing the evaluation values in the order 2D condition, 3D condition and 3D condition applied the disparity modification for happiness, surprise, and fear. This suggests the possibility that binocular disparity and the modification affect arousal.

Analysis of heat transfer under high heat flux nucleate boiling conditions

Energy Technology Data Exchange (ETDEWEB)

Liu, Y.; Dinh, N. [3145 Burlington Laboratories, Raleigh, NC (United States)

2016-07-15

Analysis was performed for a heater infrared thermometric imaging temperature data obtained from high heat flux pool boiling and liquid film boiling experiments BETA. With the OpenFOAM solver, heat flux distribution towards the coolant was obtained by solving transient heat conduction of heater substrate given the heater surface temperature data as boundary condition. The so-obtained heat flux data was used to validate them against the state-of-art wall boiling model developed by D. R. Shaver (2015) with the assumption of micro-layer hydrodynamics. Good agreement was found between the model prediction and data for conditions away from the critical heat flux (CHF). However, the data indicate a different heat transfer pattern under CHF, which is not captured by the current model. Experimental data strengthen the notion of burnout caused by the irreversible hot spot due to failure of rewetting. The observation forms a basis for a detailed modeling of micro-layer hydrodynamics under high heat flux.

Analysis of heat transfer under high heat flux nucleate boiling conditions

International Nuclear Information System (INIS)

Liu, Y.; Dinh, N.

2016-01-01

Analysis was performed for a heater infrared thermometric imaging temperature data obtained from high heat flux pool boiling and liquid film boiling experiments BETA. With the OpenFOAM solver, heat flux distribution towards the coolant was obtained by solving transient heat conduction of heater substrate given the heater surface temperature data as boundary condition. The so-obtained heat flux data was used to validate them against the state-of-art wall boiling model developed by D. R. Shaver (2015) with the assumption of micro-layer hydrodynamics. Good agreement was found between the model prediction and data for conditions away from the critical heat flux (CHF). However, the data indicate a different heat transfer pattern under CHF, which is not captured by the current model. Experimental data strengthen the notion of burnout caused by the irreversible hot spot due to failure of rewetting. The observation forms a basis for a detailed modeling of micro-layer hydrodynamics under high heat flux.

Recent advances on the posttranslational modifications of EXTs and their roles in plant cell walls

DEFF Research Database (Denmark)

Velasquez, Melina; Salter, Juan Salgado; Dorosz, Javier Gloazzo

2012-01-01

The genetic set up and the enzymes that define the O-glycosylation sites and transfer the activated sugars to cell wall glycoprotein Extensins (EXTs) have remained unknown for a long time. We are now beginning to see the emerging components of the molecular machinery that assembles these complex O......-glycoproteins on the plant cell wall. Genes conferring the posttranslational modifications, i.e., proline hydroxylation and subsequent O-glycosylation, of the EXTs have been recently identified. In this review we summarize the enzymes that define the O-glycosylation sites on the O-glycoproteins, i.e., the prolyl 4......-hydroxylases (P4Hs), the glycosyltransferases that transfer arabinose units (named arabinosyltransferases, AraTs), and the one responsible for transferring a single galactose (galactosyltransferase, GalT) on the protein EXT backbones. We discuss the effects of posttranslational modifications on the structure...

The Effect of Co-Designing on Educational Transfer between Cultures.

Science.gov (United States)

Davila, Juan Ruben; Keirns, Johanna L.

1994-01-01

Describes the role that values, and value conflicts, play in transfer of educational program effectiveness between United States and Mexico. It proposes that transfer without significant modification and interpretation to fit local world views and practices is generally dysfunctional, and offers codesigning as a strategy to obviate traditional…

Particle Distribution Modification by Low Amplitude Modes

International Nuclear Information System (INIS)

White, R.B.; Gorelenkov, N.; Heidbrink, W.W.; Van Zeeland, M.A.

2009-01-01

Modification of a high energy particle distribution by a spectrum of low amplitude modes is investigated using a guiding center code. Only through resonance are modes effective in modifying the distribution. Diagnostics are used to illustrate the mode-particle interaction and to find which effects are relevant in producing significant resonance, including kinetic Poincare plots and plots showing those orbits with time averaged mode-particle energy transfer. Effects of pitch angle scattering and drag are studied, as well as plasma rotation and time dependence of the equilibrium and mode frequencies. A specific example of changes observed in a DIII-D deuterium beam distribution in the presence of low amplitude experimentally validated Toroidal Alfven (TAE) eigenmodes and Reversed Shear Alfven (RSAE) eigenmodes is examined in detail. Comparison with experimental data shows that multiple low amplitude modes can account for significant modification of high energy beam particle distributions. It is found that there is a stochastic threshold for beam profile modification, and that the experimental amplitudes are only slightly above this threshold.

A digital computer simulation and study of a direct-energy-transfer power-conditioning system

Science.gov (United States)

Burns, W. W., III; Owen, H. A., Jr.; Wilson, T. G.; Rodriguez, G. E.; Paulkovich, J.

1975-01-01

An investigation of the behavior of the power-conditioning system as a whole is a necessity to ensure the integrity of the aggregate system in the case of space applications. An approach for conducting such an investigation is considered. A description is given of the application of a general digital analog simulator program to the study of an aggregate power-conditioning system which is being developed for use on the International Ultraviolet Explorer spacecraft. The function of the direct energy transfer system studied involves a coupling of a solar array through a main distribution bus to the spacecraft electrical loads.

Analysis of several hazardous conditions for large transfer and back-dilution sequences in Tank 241-SY-101

International Nuclear Information System (INIS)

CW Stewart; LA Mahoney; WB Barton

2000-01-01

The first transfer of 89 kgal of waste and back-dilution of 61 kgal of water in Hanford Tank 241-SY-101 was accomplished December 18--20, 1999. Limits were placed on the transfer and back-dilution volumes because of concerns about potential gas release, crust sinking, and degradation of mixer pump performance. Additional transfers and back-dilutions are being planned that will bring the total to 500 kgal, which should dissolve a large fraction of the solids in the tank and dilute it well beyond the point where significant gas retention can occur. This report provides the technical bases for removing the limits on transfer and back-dilution volume by evaluating the potential consequences of several postulated hazardous conditions in view of the results of the first campaign and results of additional analyses of waste behavior

Analysis of several hazardous conditions for large transfer and back-dilution sequences in Tank 241-SY-101

Energy Technology Data Exchange (ETDEWEB)

CW Stewart; LA Mahoney; WB Barton

2000-01-28

The first transfer of 89 kgal of waste and back-dilution of 61 kgal of water in Hanford Tank 241-SY-101 was accomplished December 18--20, 1999. Limits were placed on the transfer and back-dilution volumes because of concerns about potential gas release, crust sinking, and degradation of mixer pump performance. Additional transfers and back-dilutions are being planned that will bring the total to 500 kgal, which should dissolve a large fraction of the solids in the tank and dilute it well beyond the point where significant gas retention can occur. This report provides the technical bases for removing the limits on transfer and back-dilution volume by evaluating the potential consequences of several postulated hazardous conditions in view of the results of the first campaign and results of additional analyses of waste behavior.

Characterization of organo-modified bentonite sorbents: The effect of modification conditions on adsorption performance

International Nuclear Information System (INIS)

Parolo, María E.; Pettinari, Gisela R.; Musso, Telma B.; Sánchez-Izquierdo, María P.; Fernández, Laura G.

2014-01-01

Graphical abstract: - Highlights: • Modification of clay was evaluated by two methods for removing an organic substance. • Surfactant cations and organosilanes were intercalated into the interlayer space. • The hydrophobic surface of adsorbents increased the retention of organic substances. • Clay grafted with vinyltrimethoxysilane showed the highest adsorption for aniline. - Abstract: The organic modification of a natural bentonite was evaluated using two methods: exchanging the interlayer cations by hexadecyltrimethylammonium (HDTMA) and grafting with vinyltrimethoxysilane (VTMS) and γ-methacryloyloxy propyl trimethoxysilane (TMSPMA) on montmorillonite surface. The physicochemical characterization of all materials was made by X-ray diffraction (XRD), IR spectroscopy, thermogravimetric analysis (TGA) and Brunauer–Emmett–Teller (BET) surface area techniques. HDTMA cations and organosilanes were intercalated into the interlayer space of montmorillonite, as deduced from the increase of the basal spacing. IR spectroscopy, TGA and BET area give evidence of successful organic modification. The studies show a decrease in the IR absorption band intensity at 3465 cm −1 with surfactant modification, and also a decrease of mass loss due to adsorbed water observed in two samples: the organoclay and functionalized bentonites, which are evidences of a lower interlayer hydrophilicity. The efficiency of aniline removal onto natural bentonite, organobentonite and functionalized bentonites from aqueous solutions was evaluated. Aniline sorption on natural bentonite was studied using batch experiments, XRD and IR spectroscopy. The hydrophobic surface of organobentonite and functionalized bentonites increased the retention capacity for nonionic organic substances such as aniline on bentonites. The sorption properties of modified bentonite, through different modification methods, enhanced the potential industrial applications of bentonites in water decontamination

Aerodynamics, heat and mass transfer in steam-aerosol turbulent flows in containment

Energy Technology Data Exchange (ETDEWEB)

Nigmatulin, B.I.; Pershukov, V.A.; Ris, V.V. [Research & Engineering Centre of Nuclear Plants Safety, Moscow (Russian Federation)] [and others

1995-09-01

In this report an analysis of aerodynamic and heat transfer processes at the blowdown of gas-dispersed mixture into the containment volume is presented. A few models for description of the volume averaged and local characteristics are analyzed. The mathematical model for description of the local characteristics of the turbulent gas-dispersed flows was developed. The calculation of aerodynamic, heat and mass transfer characteristics was based on the Navier-Stokes, energy and gas mass fractions conservation equations. For calculation of dynamics and deposition of the aerosols the original diffusion-inertia model is developed. The pulsating characteristics of the gaseous phase were calculated on the base (k-{xi}) model of turbulence with modification to account thermogravitational force action and influence of particle mass loading. The appropriate boundary conditions using the {open_quotes}near-wall function{close_quotes} approach was obtained. Testing of the mathematical models and boundary conditions has shown a good agreement between computation and data of comparison. The described mathematical models were applied to two- and three dimensional calculations of the turbulent flow in containment at the various stages of the accident.

Artificial Metalloenzymes through Chemical Modification of Engineered Host Proteins

KAUST Repository

Zernickel, Anna

2014-10-01

With a few exceptions, all organisms are restricted to the 20 canonical amino acids for ribosomal protein biosynthesis. Addition of new amino acids to the genetic code can introduce novel functionalities to proteins, broadening the diversity of biochemical as well as chemical reactions and providing new tools to study protein structure, reactivity, dynamics and protein-protein-interactions. The site directed in vivo incorporation developed by P. G. SCHULTZ and coworkers, using an archeal orthogonal tRNA/aaRS (aminoacyl-tRNA synthase) pair, allows site-specifically insertion of a synthetic unnatural amino acid (UAA) by reprogramming the amber TAG stop codon. A variety of over 80 different UAAs can be introduced by this technique. However by now a very limited number can form kinetically stable bonds to late transition metals. This thesis aims to develop new catalytically active unnatural amino acids or strategies for a posttranslational modification of site-specific amino acids in order to achieve highly enantioselective metallorganic enzyme hybrids (MOEH). As a requirement a stable protein host has to be established, surviving the conditions for incorporation, posttranslational modification and the final catalytic reactions. mTFP* a fluorescent protein was genetically modified by excluding any exposed Cys, His and Met forming a variant mTFP*, which fulfills the required specifications. Posttranslational chemical modification of mTFP* allow the introduction of single site metal chelating moieties. For modification on exposed cysteines different maleiimid containing ligand structures were synthesized. In order to perform copper catalyzed click reactions, suitable unnatural amino acids (para-azido-(L)-phenylalanine, para-ethynyl-(L)-phenylalanine) were synthesized and a non-cytotoxic protocol was established. The triazole ring formed during this reaction may contribute as a moderate σ-donor/π-acceptor ligand to the metal binding site. Since the cell limits the

Two Dimensional CFD Analyses on the Heat Transfer for a Supercritical Pressure CO{sub 2}

Energy Technology Data Exchange (ETDEWEB)

Cho, Bong Hyun; Kim, Young In; Bae, Yoon Yeong [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

2005-07-01

The Supercritical Water Cooled Reactor(SCWR) operates in a pressure around 25MPa and temperature of 293{approx}510 .deg. C. In order to study the heat transfer behaviors and good comparisons between the various fluids, a heat transfer test loop(SPHINX) using CO{sub 2} has been constructed in KAERI as a part of international research program, I-NERI. At a supercritical pressure, the heat transfer coefficient is much larger than that estimated from the Dittus-Boelter correlation for a relatively large flow rate with moderate wall heat flux conditions. This phenomenon was explained by the rapid variations of the physical properties near the wall with the temperature. On the contrary, the heat transfer becomes worse when the bulk fluid enthalpy is below the pseudo-critical enthalpy under a low flow rate with large heat flux conditions. This phenomenon is called 'deteriorated heat transfer', and which is explained as the modification of the shear stress distribution across the tube to a buoyancy and/or acceleration in a low density layer near the wall, with the consequence of a turbulence. The upward vertical flow of CO{sub 2} through a uniformly heated tube of 4.4 mm in diameter and 3m long(heated length is 2.1m) was investigated numerically using the CFD code, FLUENT. Through the numerical simulations, we have attempted to obtain a physically meaningful insight into the heat transfer mechanisms at a supercritical pressure.

Sensitive analysis and modifications to reflood-related constitutive models of RELAP5

International Nuclear Information System (INIS)

Li Dong; Liu Xiaojing; Yang Yanhua

2014-01-01

Previous system code calculation reveals that the cladding temperature is underestimated and quench front appears too early during reflood process. To find out the parameters shows important effect on the results, sensitive analysis is performed on parameters of constitutive physical models. Based on the phenomenological and theoretical analysis, four parameters are selected: wall to vapor film boiling heat transfer coefficient, wall to liquid film boiling heat transfer coefficient, dry wall interfacial friction coefficient and minimum droplet diameter. In order to improve the reflood simulation ability of RELAP5 code, the film boiling heat transfer model and dry wall interfacial friction model which are corresponding models of those influential parameters are studied. Modifications have been made and installed into RELAP5 code. Six tests of FEBA are simulated by RELAP5 to study the predictability of reflood-related physical models. A dispersed flow film boiling heat transfer (DFFB) model is applied when void fraction is above 0.9. And a factor is multiplied to the post-CHF drag coefficient to fit the experiment better. Finally, the six FEBA tests are calculated again so as to assess the modifications. Better results are obtained which prove the advantage of the modified models. (author)

Geochemical Data for Upper Mineral Creek, Colorado, Under Existing Ambient Conditions and During an Experimental pH Modification, August 2005

Science.gov (United States)

Runkel, Robert L.; Kimball, Briant A.; Steiger, Judy I.; Walton-Day, Katherine

2009-01-01

Mineral Creek, an acid mine drainage stream in south-western Colorado, was the subject of a water-quality study that employed a paired synoptic approach. Under the paired synoptic approach, two synoptic sampling campaigns were conducted on the same study reach. The initial synoptic campaign, conducted August 22, 2005, documented stream-water quality under existing ambient conditions. A second synoptic campaign, conducted August 24, 2005, documented stream-water quality during a pH-modification experiment that elevated the pH of Mineral Creek. The experimental pH modification was designed to determine the potential reductions in dissolved constituent concentrations that would result from the implementation of an active treatment system for acid mine drainage. During both synoptic sampling campaigns, a solution containing lithium bromide was injected continuously to allow for the calculation of streamflow using the tracer-dilution method. Synoptic water-quality samples were collected from 30 stream sites and 11 inflow locations along the 2-kilometer study reach. Data from the study provide spatial profiles of pH, concentration, and streamflow under both existing and experimentally-altered conditions. This report presents the data obtained August 21-24, 2005, as well as the methods used for sample collection and data analysis.

Modification of the perturbative QCD towards confinement

International Nuclear Information System (INIS)

Arodz, H.

1981-01-01

Modification of the low momentum behaviour of the perturbative SU(2) gauge theory is proposed. The modification is closely related (although not equivalent) to a nonstandard choice of boundary condition for the Euclidean 2-point gluonic Green function. In the resulting theory already single graphs lead to the confining potential between heavy, static quarks, V(r) = ar 2 for r → infinity. (author)

Barley lipid transfer protein, LTP1, contains a new type of lipid-like post-translational modification

DEFF Research Database (Denmark)

Lindorff-Larsen, Kresten; Lerche, Mathilde H.; Poulsen, Flemming Martin

2001-01-01

in which an aspartic acid in LTP1 is bound to the modification through what most likely is an ester bond. The chemical structure of the modification has been characterized by means of two-dimensional homo- and heteronuclear nuclear magnetic resonance spectroscopy as well as mass spectrometry and is found...

The computational nature of memory modification.

Science.gov (United States)

Gershman, Samuel J; Monfils, Marie-H; Norman, Kenneth A; Niv, Yael

2017-03-15

Retrieving a memory can modify its influence on subsequent behavior. We develop a computational theory of memory modification, according to which modification of a memory trace occurs through classical associative learning, but which memory trace is eligible for modification depends on a structure learning mechanism that discovers the units of association by segmenting the stream of experience into statistically distinct clusters (latent causes). New memories are formed when the structure learning mechanism infers that a new latent cause underlies current sensory observations. By the same token, old memories are modified when old and new sensory observations are inferred to have been generated by the same latent cause. We derive this framework from probabilistic principles, and present a computational implementation. Simulations demonstrate that our model can reproduce the major experimental findings from studies of memory modification in the Pavlovian conditioning literature.

Heat transfer to water at supercritical pressures in a circular and square annular flow geometry

International Nuclear Information System (INIS)

Licht, Jeremy; Anderson, Mark; Corradini, Michael

2008-01-01

A supercritical water heat transfer facility has been built at the University of Wisconsin to study heat transfer in a circular and square annular flow channel. Operating conditions included mass velocities of 350-1425 kg/m 2 s, heat fluxes up to 1.0 MW/m 2 , and bulk inlet temperatures up to 400 o C; all at a pressure of 25 MPa. The accuracy and validity of selected heat transfer correlations and buoyancy criterion were compared with heat transfer measurements. Jackson's Nusselt correlation was able to best predict the test data, capturing 86% of the data within 25%. Watts Nusselt correlation showed a similar trend but under predicted measurements by 10% relative to Jackson's. Comparison of experimental results with results of previous investigators has shown general agreement with high mass velocity data. Low mass velocity data have provided some insight into the difficulty in applying these Nusselt correlations to a region of deteriorated heat transfer. Geometrical differences in heat transfer were seen when deterioration was present. Jackson's buoyancy criterion predicted the onset of deterioration while modifications were applied to Seo's Froude number based criterion

Measurements of Sheath Temperature Profiles in Bruce LVRF Bundles Under Post-Dryout Heat Transfer Conditions in Freon

International Nuclear Information System (INIS)

Guo, Y.; Bullock, D.E.; Pioro, I.L.; Martin, J.

2006-01-01

An experimental program has been completed to study the behaviour of sheath wall temperatures in the Bruce Power Station Low Void Reactivity Fuel (shortened hereafter to Bruce LVRF) bundles under post-dryout (PDO) heat-transfer conditions. The experiment was conducted with an electrically heated simulator of a string of nine Bruce LVRF bundles, installed in the MR-3 Freon heat transfer loop at the Chalk River Laboratories (CRL), Atomic Energy of Canada Limited (AECL). The loop used Freon R-134a as a coolant to simulate typical flow conditions in CANDU R nuclear power stations. The simulator had an axially uniform heat flux profile. Two radial heat flux profiles were tested: a fresh Bruce LVRF profile and a fresh natural uranium (NU) profile. For a given set of flow conditions, the channel power was set above the critical power to achieve dryout, while heater-element wall temperatures were recorded at various overpower levels using sliding thermocouples. The maximum experimental overpower achieved was 64%. For the conditions tested, the results showed that initial dryout occurred at an inner-ring element at low flows and an outer-ring element facing internal subchannels at high flows. Dry-patches (regions of dryout) spread with increasing channel power; maximum wall temperatures were observed at the downstream end of the simulator, and immediately upstream of the mid-bundle spacer plane. In general, maximum wall temperatures were observed at the outer-ring elements facing the internal subchannels. The maximum water-equivalent temperature obtained in the test, at an overpower level of 64%, was significantly below the acceptable maximum temperature, indicating that the integrity of the Bruce LVRF will be maintained at PDO conditions. Therefore, the Bruce LVRF exhibits good PDO heat transfer performance. (authors)

Numerical investigation on the convective heat transfer in a spiral coil with radiant heating

Directory of Open Access Journals (Sweden)

Đorđević Milan Lj.

2016-01-01

Full Text Available The objective of this study was to numerically investigate the heat transfer in spiral coil tube in the laminar, transitional, and turbulent flow regimes. The Archimedean spiral coil was exposed to radiant heating and should represent heat absorber of parabolic dish solar concentrator. Specific boundary conditions represent the uniqueness of this study, since the heat flux upon the tube external surfaces varies not only in the circumferential direction, but also in the axial direction. The curvature ratio of spiral coil varies from 0.029 at the flow inlet to 0.234 at the flow outlet, while the heat transfer fluid is water. The 3-D steady-state transport equations were solved using the Reynolds stress turbulence model. Results showed that secondary flows strongly affect the flow and that the heat transfer is strongly asymmetric, with higher values near the outer wall of spiral. Although overall turbulence levels were lower than in a straight pipe, heat transfer rates were larger due to the curvature-induced modifications of the mean flow and temperature fields. [Projekat Ministarstva nauke Republike Srbije, br. 42006

Evidence of eligibility manipulation for conditional cash transfer programs

Directory of Open Access Journals (Sweden)

Sergio Firpo

2014-09-01

Full Text Available This paper assesses whether eligibility for conditional cash transfer programs has been manipulated, as well as the impact of this phenomenon on time allocation within households. To perform this analysis, we use data from the 2006 PNAD (Brazilian national household survey and investigate the eligibility manipulation for the Bolsa Família (Family Stipend program during this time period. The program assists families with a monthly per capita income of around R$120.00 (US$60.00. By applying the tests developed by McCrary (2008, we find suggestive evidence that individuals manipulate their income by voluntarily reducing their labor supply in order to become eligible to the program. Moreover, the reduction in labor supply is greater among women, especially single or divorced mothers. This evidence raises some concern about the unintended consequences related to the eligibility criteria utilized by Bolsa Família, as well as the program's impact on individuals living in extreme poverty.

Characterization of organo-modified bentonite sorbents: The effect of modification conditions on adsorption performance

Energy Technology Data Exchange (ETDEWEB)

Parolo, María E., E-mail: maria.parolo@fain.uncoma.edu.ar [Instituto de Investigación y Desarrollo en Ingeniería de Procesos, Biotecnología y Energías Alternativas (PROBIEN), Facultad de Ingeniería, Universidad Nacional del Comahue, Neuquén 8300 (Argentina); Pettinari, Gisela R. [Instituto de Investigación y Desarrollo en Ingeniería de Procesos, Biotecnología y Energías Alternativas (PROBIEN), Facultad de Ingeniería, Universidad Nacional del Comahue, Neuquén 8300 (Argentina); Musso, Telma B. [Instituto de Investigación y Desarrollo en Ingeniería de Procesos, Biotecnología y Energías Alternativas (PROBIEN), Facultad de Ingeniería, Universidad Nacional del Comahue, Neuquén 8300 (Argentina); CONICET, Consejo Nacional de Investigaciones Científicas y Técnicas, Buenos Aires (Argentina); Sánchez-Izquierdo, María P.; Fernández, Laura G. [Facultad de Ingeniería, Universidad Nacional del Comahue, Neuquén 8300 (Argentina)

2014-11-30

Graphical abstract: - Highlights: • Modification of clay was evaluated by two methods for removing an organic substance. • Surfactant cations and organosilanes were intercalated into the interlayer space. • The hydrophobic surface of adsorbents increased the retention of organic substances. • Clay grafted with vinyltrimethoxysilane showed the highest adsorption for aniline. - Abstract: The organic modification of a natural bentonite was evaluated using two methods: exchanging the interlayer cations by hexadecyltrimethylammonium (HDTMA) and grafting with vinyltrimethoxysilane (VTMS) and γ-methacryloyloxy propyl trimethoxysilane (TMSPMA) on montmorillonite surface. The physicochemical characterization of all materials was made by X-ray diffraction (XRD), IR spectroscopy, thermogravimetric analysis (TGA) and Brunauer–Emmett–Teller (BET) surface area techniques. HDTMA cations and organosilanes were intercalated into the interlayer space of montmorillonite, as deduced from the increase of the basal spacing. IR spectroscopy, TGA and BET area give evidence of successful organic modification. The studies show a decrease in the IR absorption band intensity at 3465 cm{sup −1} with surfactant modification, and also a decrease of mass loss due to adsorbed water observed in two samples: the organoclay and functionalized bentonites, which are evidences of a lower interlayer hydrophilicity. The efficiency of aniline removal onto natural bentonite, organobentonite and functionalized bentonites from aqueous solutions was evaluated. Aniline sorption on natural bentonite was studied using batch experiments, XRD and IR spectroscopy. The hydrophobic surface of organobentonite and functionalized bentonites increased the retention capacity for nonionic organic substances such as aniline on bentonites. The sorption properties of modified bentonite, through different modification methods, enhanced the potential industrial applications of bentonites in water decontamination.

Effects of a Modified Conditional Cash Transfer Program in Two American Cities: Findings from Family Rewards 2.0

Science.gov (United States)

Miller, Cynthia; Miller, Rhiannon; Verma, Nandita; Dechausay, Nadine; Yang, Edith; Rudd, Timothy; Rodriguez, Jonathan; Honig, Sylvie

2016-01-01

Family Rewards was an innovative approach to poverty reduction in the United States that was modeled on the conditional cash transfer (CCT) programs common in lower- and middle-income countries. The program offered cash assistance to low-income families, provided that they met certain conditions related to family health care, children's education,…

Characterization of organo-modified bentonite sorbents: The effect of modification conditions on adsorption performance

Science.gov (United States)

Parolo, María E.; Pettinari, Gisela R.; Musso, Telma B.; Sánchez-Izquierdo, María P.; Fernández, Laura G.

2014-11-01

The organic modification of a natural bentonite was evaluated using two methods: exchanging the interlayer cations by hexadecyltrimethylammonium (HDTMA) and grafting with vinyltrimethoxysilane (VTMS) and γ-methacryloyloxy propyl trimethoxysilane (TMSPMA) on montmorillonite surface. The physicochemical characterization of all materials was made by X-ray diffraction (XRD), IR spectroscopy, thermogravimetric analysis (TGA) and Brunauer-Emmett-Teller (BET) surface area techniques. HDTMA cations and organosilanes were intercalated into the interlayer space of montmorillonite, as deduced from the increase of the basal spacing. IR spectroscopy, TGA and BET area give evidence of successful organic modification. The studies show a decrease in the IR absorption band intensity at 3465 cm-1 with surfactant modification, and also a decrease of mass loss due to adsorbed water observed in two samples: the organoclay and functionalized bentonites, which are evidences of a lower interlayer hydrophilicity. The efficiency of aniline removal onto natural bentonite, organobentonite and functionalized bentonites from aqueous solutions was evaluated. Aniline sorption on natural bentonite was studied using batch experiments, XRD and IR spectroscopy. The hydrophobic surface of organobentonite and functionalized bentonites increased the retention capacity for nonionic organic substances such as aniline on bentonites. The sorption properties of modified bentonite, through different modification methods, enhanced the potential industrial applications of bentonites in water decontamination.

Efficient reanalysis of structures by a direct modification method. [local stiffness modifications of large structures

Science.gov (United States)

Raibstein, A. I.; Kalev, I.; Pipano, A.

1976-01-01

A procedure for the local stiffness modifications of large structures is described. It enables structural modifications without an a priori definition of the changes in the original structure and without loss of efficiency due to multiple loading conditions. The solution procedure, implemented in NASTRAN, involved the decomposed stiffness matrix and the displacement vectors of the original structure. It solves the modified structure exactly, irrespective of the magnitude of the stiffness changes. In order to investigate the efficiency of the present procedure and to test its applicability within a design environment, several real and large structures were solved. The results of the efficiency studies indicate that the break-even point of the procedure varies between 8% and 60% stiffness modifications, depending upon the structure's characteristics and the options employed.

Simulation of the steady-state energy transfer in rigid bodies, with convective-radiative boundary conditions, employing a minimum principle

International Nuclear Information System (INIS)

Gama, R.M.S. da.

1992-08-01

The energy transfer phenomenon in a rigid and opaque body that exchanges energy, with the environment, by convection and by diffuse thermal radiation is studied. The considered phenomenon is described by a partial differential equation, subjected to (nonlinear) boundary conditions. A minimum principle, suitable for a large class of energy transfer problems is presented. Some particular cases are simulated. (author)

Where does the money go? Assessing the expenditure and income effects of the Philippines' Conditional Cash Transfer Program

OpenAIRE

Stella Luz A. Quimbo; Joseph J. Capuno; Aleli D. Kraft; Rhea Molato; Carlos Tan, Jr.

2015-01-01

Evaluation studies on conditional cash transfers (CCT) in the Philippines found small if not insignificantly different from zero effects on household consumption. We use propensity score matching to examine how recipients made use of the money they received, taking into account possible changes in recipient behavior. We find evidence of crowding in - CCT households receive higher transfers from other domestic sources as a positive spillover from becoming CCT beneficiaries Poor CCT households ...

Field calibration and modification of scs design equation for predicting length of border under local conditions

International Nuclear Information System (INIS)

Choudhary, M.R.; Mustafa, U.S.

2009-01-01

Field tests were conducted to calibrate the existing SCS design equation in determining field border length using field data of different field lengths during 2nd and 3rd irrigations under local conditions. A single ring infiltrometer was used to estimate the water movement into and through the irrigated soil profile and in estimating the coefficients of Kostiakov infiltration function. Measurements of the unit discharge and time of advance were carried out during different irrigations on wheat irrigated fields having clay loam soil. The collected field data were used to calibrate the existing SCS design equation developed by USDA for testing its validity under local field conditions. SCS equation was modified further to improve its applicability. Results from the study revealed that the Kostiakov model over predicted the coefficients, which in turn overestimated the water advance length for boarder in the selected field using existing SCS design equation. However, the calibrated SCS design equation after parametric modification produced more satisfactory results encouraging the scientists to make its use at larger scale. (author)

New Findings on New York City's Conditional Cash Transfer Program. Fast Focus. No. 18-2013

Science.gov (United States)

Riccio, James A.

2013-01-01

The Earned Income Tax Credit (EITC) and Temporary Assistance for Needy Families (TANF) are long-standing policies that link cash assistance to low-income families to work effort. A new policy being tested in New York City adopts this "conditional cash transfer" principle and extends it to a broader set of family efforts to build their…

To transfer or not to transfer? Kinematics and laterality quotient predict interlimb transfer of motor learning.

Science.gov (United States)

Lefumat, Hannah Z; Vercher, Jean-Louis; Miall, R Chris; Cole, Jonathan; Buloup, Frank; Bringoux, Lionel; Bourdin, Christophe; Sarlegna, Fabrice R

2015-11-01

Humans can remarkably adapt their motor behavior to novel environmental conditions, yet it remains unclear which factors enable us to transfer what we have learned with one limb to the other. Here we tested the hypothesis that interlimb transfer of sensorimotor adaptation is determined by environmental conditions but also by individual characteristics. We specifically examined the adaptation of unconstrained reaching movements to a novel Coriolis, velocity-dependent force field. Right-handed subjects sat at the center of a rotating platform and performed forward reaching movements with the upper limb toward flashed visual targets in prerotation, per-rotation (i.e., adaptation), and postrotation tests. Here only the dominant arm was used during adaptation and interlimb transfer was assessed by comparing performance of the nondominant arm before and after dominant-arm adaptation. Vision and no-vision conditions did not significantly influence interlimb transfer of trajectory adaptation, which on average was significant but limited. We uncovered a substantial heterogeneity of interlimb transfer across subjects and found that interlimb transfer can be qualitatively and quantitatively predicted for each healthy young individual. A classifier showed that in our study, interlimb transfer could be predicted based on the subject's task performance, most notably motor variability during learning, and his or her laterality quotient. Positive correlations suggested that variability of motor performance and lateralization of arm movement control facilitate interlimb transfer. We further show that these individual characteristics can predict the presence and the magnitude of interlimb transfer of left-handers. Overall, this study suggests that individual characteristics shape the way the nervous system can generalize motor learning. Copyright © 2015 the American Physiological Society.

The Impact of Conditional Cash Transfer on Toilet Use in eThekwini, South Africa

Directory of Open Access Journals (Sweden)

Elizabeth Tilley

2016-10-01

Full Text Available In the developing world, having access to a toilet does not necessarily imply use: infrequent or non-use limits the desired health outcomes of improved sanitation. We examine the sanitation situation in a rural part of South Africa where recipients of novel, waterless “urine-diverting dry toilets” are not regularly using them. In order to determine if small, conditional cash transfers (CCT could motivate families to use their toilets more, we paid for urine via different incentive-based interventions: two were based on volumetric pricing and the third was a flat-rate payment (irrespective of volume. A flat-rate payment (approx. €1 resulted in the highest rates of regular (weekly participation at 59%. The low volumetric payment (approx. €0.05/L led to regular participation rates of only 12% and no increase in toilet use. The high volumetric payment (approx. €0.1/L resulted in lower rates of regular participation (35%, but increased the average urine production per household per day by 74%. As a first example of conditional cash transfers being used in the sanitation sector, we show that they are an accepted and effective tool for increasing toilet use, while putting small cash payments in the hands of poor, largely unemployed populations in rural South Africa.

Subcritical Water Hydrolysis of Peptides: Amino Acid Side-Chain Modifications

Science.gov (United States)

Powell, Thomas; Bowra, Steve; Cooper, Helen J.

2017-09-01

Previously we have shown that subcritical water may be used as an alternative to enzymatic digestion in the proteolysis of proteins for bottom-up proteomics. Subcritical water hydrolysis of proteins was shown to result in protein sequence coverages greater than or equal to that obtained following digestion with trypsin; however, the percentage of peptide spectral matches for the samples treated with trypsin were consistently greater than for those treated with subcritical water. This observation suggests that in addition to cleavage of the peptide bond, subcritical water treatment results in other hydrolysis products, possibly due to modifications of amino acid side chains. Here, a model peptide comprising all common amino acid residues (VQSIKCADFLHYMENPTWGR) and two further model peptides (VCFQYMDRGDR and VQSIKADFLHYENPTWGR) were treated with subcritical water with the aim of probing any induced amino acid side-chain modifications. The hydrolysis products were analyzed by direct infusion electrospray tandem mass spectrometry, either collision-induced dissociation or electron transfer dissociation, and liquid chromatography collision-induced dissociation tandem mass spectrometry. The results show preferential oxidation of cysteine to sulfinic and sulfonic acid, and oxidation of methionine. In the absence of cysteine and methionine, oxidation of tryptophan was observed. In addition, water loss from aspartic acid and C-terminal amidation were observed in harsher subcritical water conditions. [Figure not available: see fulltext.

Conditions for Lorentz-invariant superluminal information transfer without signaling

Science.gov (United States)

Grössing, G.; Fussy, S.; Mesa Pascasio, J.; Schwabl, H.

2016-03-01

We understand emergent quantum mechanics in the sense that quantum mechanics describes processes of physical emergence relating an assumed sub-quantum physics to macroscopic boundary conditions. The latter can be shown to entail top-down causation, in addition to usual bottom-up scenarios. With this example it is demonstrated that definitions of “realism” in the literature are simply too restrictive. A prevailing manner to define realism in quantum mechanics is in terms of pre-determination independent of the measurement. With our counter-example, which actually is ubiquitous in emergent, or self-organizing, systems, we argue for realism without pre-determination. We refer to earlier results of our group showing how the guiding equation of the de Broglie-Bohm interpretation can be derived from a theory with classical ingredients only. Essentially, this corresponds to a “quantum mechanics without wave functions” in ordinary 3-space, albeit with nonlocal correlations. This, then, leads to the central question of how to deal with the nonlocality problem in a relativistic setting. We here show that a basic argument discussing the allegedly paradox time ordering of events in EPR-type two-particle experiments falls short of taking into account the contextuality of the experimental setup. Consequently, we then discuss under which circumstances (i.e. physical premises) superluminal information transfer (but not signaling) may be compatible with a Lorentz-invariant theory. Finally, we argue that the impossibility of superluminal signaling - despite the presence of superluminal information transfer - is not the result of some sort of conspiracy (á la “Nature likes to hide”), but the consequence of the impossibility to exactly reproduce in repeated experimental runs a state's preparation, or of the no-cloning theorem, respectively.

Conditions for Lorentz-invariant superluminal information transfer without signaling

International Nuclear Information System (INIS)

Grössing, G; Fussy, S; Pascasio, J Mesa; Schwabl, H

2016-01-01

We understand emergent quantum mechanics in the sense that quantum mechanics describes processes of physical emergence relating an assumed sub-quantum physics to macroscopic boundary conditions. The latter can be shown to entail top-down causation, in addition to usual bottom-up scenarios. With this example it is demonstrated that definitions of “realism” in the literature are simply too restrictive. A prevailing manner to define realism in quantum mechanics is in terms of pre-determination independent of the measurement. With our counter-example, which actually is ubiquitous in emergent, or self-organizing, systems, we argue for realism without pre-determination. We refer to earlier results of our group showing how the guiding equation of the de Broglie-Bohm interpretation can be derived from a theory with classical ingredients only. Essentially, this corresponds to a “quantum mechanics without wave functions” in ordinary 3-space, albeit with nonlocal correlations. This, then, leads to the central question of how to deal with the nonlocality problem in a relativistic setting. We here show that a basic argument discussing the allegedly paradox time ordering of events in EPR-type two-particle experiments falls short of taking into account the contextuality of the experimental setup. Consequently, we then discuss under which circumstances (i.e. physical premises) superluminal information transfer (but not signaling) may be compatible with a Lorentz-invariant theory. Finally, we argue that the impossibility of superluminal signaling - despite the presence of superluminal information transfer - is not the result of some sort of conspiracy (á la “Nature likes to hide”), but the consequence of the impossibility to exactly reproduce in repeated experimental runs a state's preparation, or of the no-cloning theorem, respectively. (paper)

Modification of cadmium pigments for colouring of polyolefins

International Nuclear Information System (INIS)

Kalinskaya, T.V.; Livshits, I.M.

1976-01-01

Modification conditions are studied of cadmium pigments, obtained by different methods, aliphatic acids(C 5 , C 8 and C 17 ). It is found, that cadmium pigments can adsorb acids with the number of atoms of carbon not less than 8. Stearic acid adsorption on lemon cadmium pigment taken as an example has shown the efficiency of pigment modification influence on its dispersancy in non-polar medium. Modification of yellow cadmium pigments of stearic acid makes possible to obtain pigment output forms ensuring a good particle distribution during polyolefine colouring

Learning Together: How Families Responded to Education Incentives in New York City's Conditional Cash Transfer Program

Science.gov (United States)

Greenberg, David; Dechausay, Nadine; Fraker, Carolyn

2011-01-01

In 2007, New York City's Center for Economic Opportunity launched Opportunity NYC-Family Rewards, an experimental, privately funded, conditional cash transfer (CCT) program to help families break the cycle of poverty. Family Rewards provided payments to low-income families in six of the city's poorest communities for achieving specific goals…

Educational Impacts and Cost-Effectiveness of Conditional Cash Transfer Programs in Developing Countries: A Meta-Analysis

Science.gov (United States)

García, Sandra; Saavedra, Juan E.

2017-01-01

We meta-analyze for impact and cost-effectiveness 94 studies from 47 conditional cash transfer programs in low- and middle-income countries worldwide, focusing on educational outcomes that include enrollment, attendance, dropout, and school completion. To conceptually guide and interpret the empirical findings of our meta-analysis, we present a…

The computational nature of memory modification

Science.gov (United States)

Gershman, Samuel J; Monfils, Marie-H; Norman, Kenneth A; Niv, Yael

2017-01-01

Retrieving a memory can modify its influence on subsequent behavior. We develop a computational theory of memory modification, according to which modification of a memory trace occurs through classical associative learning, but which memory trace is eligible for modification depends on a structure learning mechanism that discovers the units of association by segmenting the stream of experience into statistically distinct clusters (latent causes). New memories are formed when the structure learning mechanism infers that a new latent cause underlies current sensory observations. By the same token, old memories are modified when old and new sensory observations are inferred to have been generated by the same latent cause. We derive this framework from probabilistic principles, and present a computational implementation. Simulations demonstrate that our model can reproduce the major experimental findings from studies of memory modification in the Pavlovian conditioning literature. DOI: http://dx.doi.org/10.7554/eLife.23763.001 PMID:28294944

Anode modification with formic acid: A simple and effective method to improve the power generation of microbial fuel cells

Energy Technology Data Exchange (ETDEWEB)

Liu, Weifeng; Cheng, Shaoan, E-mail: shaoancheng@zju.edu.cn; Guo, Jian

2014-11-30

Highlights: • Carbon cloth anode is modified with formic acid by a simple and reliable approach. • The modification significantly enhances the power output of microbial fuel cells. • The modified anode surface favors the bacterial attachment and growth on anode. • The electron transfer rate of anode is promoted. - Abstract: The physicochemical properties of anode material directly affect the anodic biofilm formation and electron transfer, thus are critical for the power generation of microbial fuel cells (MFCs). In this work, carbon cloth anode was modified with formic acid to enhance the power production of MFCs. Formic acid modification of anode increased the maximum power density of a single-chamber air-cathode MFC by 38.1% (from 611.5 ± 6 mW/m{sup 2} to 877.9 ± 5 mW/m{sup 2}). The modification generated a cleaner electrode surface and a reduced content of oxygen and nitrogen groups on the anode. The surface changes facilitated bacterial growth on the anode and resulted in an optimized microbial community. Thus, the electron transfer rate on the modified anodes was enhanced remarkably, contributing to a higher power output of MFCs. Anode modification with formic acid could be an effective and simple method for improving the power generation of MFCs. The modification method holds a huge potential for large scale applications and is valuable for the scale-up and commercialization of microbial fuel cells.

Tyrosine Sulfation as a Protein Post-Translational Modification

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Yuh-Shyong Yang

2015-01-01

Full Text Available Integration of inorganic sulfate into biological molecules plays an important role in biological systems and is directly involved in the instigation of diseases. Protein tyrosine sulfation (PTS is a common post-translational modification that was first reported in the literature fifty years ago. However, the significance of PTS under physiological conditions and its link to diseases have just begun to be appreciated in recent years. PTS is catalyzed by tyrosylprotein sulfotransferase (TPST through transfer of an activated sulfate from 3'-phosphoadenosine-5'-phosphosulfate to tyrosine in a variety of proteins and peptides. Currently, only a small fraction of sulfated proteins is known and the understanding of the biological sulfation mechanisms is still in progress. In this review, we give an introductory and selective brief review of PTS and then summarize the basic biochemical information including the activity and the preparation of TPST, methods for the determination of PTS, and kinetics and reaction mechanism of TPST. This information is fundamental for the further exploration of the function of PTS that induces protein-protein interactions and the subsequent biochemical and physiological reactions.

Effect of the Modification of the Start-Up Sequence on the Thermal Stresses for a Microgas Turbine

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Oscar Tenango-Pirin

2016-01-01

Full Text Available Microgas turbines (MGT are an alternative for small-scale energy production; however, their small size becomes a drawback since it enhances the heat transfer among their components. Moreover, heat transfer drives to temperature gradients which become higher during transient cycles like start-up. The influence of different start-up curves on temperature and thermal stresses of a microgas turbine was investigated. Stationary and rotational blades of the turbine were numerically simulated using CFD and FEM commercial codes. Conjugated heat transfer cases were solved for obtaining heat transfer from fluid toward the blades. Changes of temperature gradients within the blades during the start-ups were calculated under transient state with boundary conditions according to each curve to assess accurate thermal stresses calculations. Results showed that the modification of the start-up curves had an impact on the thermal stresses levels and on the time when highest stresses appeared on each component. Furthermore, zones highly stressed were located near the constraints of blades where thermal strains are restricted. It was also found that the curve that had a warming period at the beginning of the start-up allowed reducing the peaks of stresses making it more feasible and safer for the turbine start-up operation.

Determination of maximum power transfer conditions of bimorph piezoelectric energy harvesters

KAUST Repository

Ahmad, Mahmoud Al

2012-07-23

In this paper, a method to find the maximum power transfer conditions in bimorph piezoelectric-based harvesters is proposed. Explicitly, we derive a closed form expression that relates the load resistance to the mechanical parameters describing the bimorph based on the electromechanical, single degree of freedom, analogy. Further, by taking into account the intrinsic capacitance of the piezoelectric harvester, a more descriptive expression of the resonant frequency in piezoelectric bimorphs was derived. In interest of impartiality, we apply the proposed philosophy on previously published experimental results and compare it with other reported hypotheses. It was found that the proposed method was able to predict the actual optimum load resistance more accurately than other methods reported in the literature. © 2012 American Institute of Physics.

Combinations of chromosome transfer and genome editing for the development of cell/animal models of human disease and humanized animal models.

Science.gov (United States)

Uno, Narumi; Abe, Satoshi; Oshimura, Mitsuo; Kazuki, Yasuhiro

2018-02-01

Chromosome transfer technology, including chromosome modification, enables the introduction of Mb-sized or multiple genes to desired cells or animals. This technology has allowed innovative developments to be made for models of human disease and humanized animals, including Down syndrome model mice and humanized transchromosomic (Tc) immunoglobulin mice. Genome editing techniques are developing rapidly, and permit modifications such as gene knockout and knockin to be performed in various cell lines and animals. This review summarizes chromosome transfer-related technologies and the combined technologies of chromosome transfer and genome editing mainly for the production of cell/animal models of human disease and humanized animal models. Specifically, these include: (1) chromosome modification with genome editing in Chinese hamster ovary cells and mouse A9 cells for efficient transfer to desired cell types; (2) single-nucleotide polymorphism modification in humanized Tc mice with genome editing; and (3) generation of a disease model of Down syndrome-associated hematopoiesis abnormalities by the transfer of human chromosome 21 to normal human embryonic stem cells and the induction of mutation(s) in the endogenous gene(s) with genome editing. These combinations of chromosome transfer and genome editing open up new avenues for drug development and therapy as well as for basic research.

Heat and Mass Transfer in a High-Porous Low-Temperature Thermal Insulation in Real Operating Conditions

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Polovnikov Vyacheslav Yu.

2015-01-01

Full Text Available The results of numerical simulation of heat and mass transfer in a high-porous low-temperature insulation in conditions of insulation freezing, a moisture migration to the front of phase transition and a condensation forming on an outer contour of interaction were obtained. Values of heat leakage were established.

Can Social Protection Weaken Clientelism? Considering Conditional Cash Transfers as Political Reform in the Philippines

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Arun Ranga Swamy

2016-01-01

Full Text Available Since poverty is often believed to be a root cause of clientelism, government policies to reduce poverty should also help to reduce clientelism. However, scholars studying clientelism are more likely to view social policy as a potential resource for clientelist politicians. This article examines this paradox in the Philippine context by offering a general framework to identify when social welfare policies are likely to reduce clientelism, and by applying this framework to the Philippines, focusing on the Pantawid Pamilyang Pilipino conditional cash transfer programme, or Pantawid. I argue that the policies that are most likely to undercut clientelism are universal social protection policies that provide poor families with security, although these are the least acceptable to middle-class taxpayers. This is exemplified by the Philippines, which has tended to introduce social policies that increase the scope for clientelism by making discretionary allocation more likely, rather than policies that offer income security to the poor. The Pantawid programme attempts to overcome these problems by introducing a centralised targeting mechanism to identify beneficiaries and by guaranteeing the benefit to all eligible families, but like all conditional cash transfer programs falls short of guaranteed and universal social protection.

Corrosion of heat exchanger materials under heat transfer conditions

International Nuclear Information System (INIS)

Tapping, R.L.; Lavoie, P.A.; Disney, D.J.

1987-01-01

Severe pitting has occurred in moderator heat exchangers tubed with Incoloy-800 in Pickering Nuclear Generating Station. The pitting originated on the cooling side (outside) of the tubes and perforation occurred in less than two years. It was known from corrosion testing at CRNL that Incoloy-800 was not susceptible to pitting in Lake Ontario water under isothermal conditions. Corrosion testing with heat transfer across the tube wall was carried out, and it was noted that severe pitting could occur under deposits formed on the tubes in silty Lake Ontario water. Subsequent testing, carried out in co-operation with Ontario Hydro Research Division, investigated the pitting resistance of other candidate tubing alloys: Incoloy-825, 904 L stainless steel, AL-6X, Inconel-625, 70:30 Cu:Ni, titanium, Sanicro-30 and Sanicro-28 1 . Of these, only titanium and Sanicro-28 have not suffered some degree of pitting attack in silt-containing Lake Ontario Water. In the absence of silt, and hence deposits, no pitting took place on any of the alloys tested

Designed Surface Residue Substitutions in [NiFe] Hydrogenase that Improve Electron Transfer Characteristics

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Isaac T. Yonemoto

2015-01-01

Full Text Available Photobiological hydrogen production is an attractive, carbon-neutral means to convert solar energy to hydrogen. We build on previous research improving the Alteromonas macleodii “Deep Ecotype” [NiFe] hydrogenase, and report progress towards creating an artificial electron transfer pathway to supply the hydrogenase with electrons necessary for hydrogen production. Ferredoxin is the first soluble electron transfer mediator to receive high-energy electrons from photosystem I, and bears an electron with sufficient potential to efficiently reduce protons. Thus, we engineered a hydrogenase-ferredoxin fusion that also contained several other modifications. In addition to the C-terminal ferredoxin fusion, we truncated the C-terminus of the hydrogenase small subunit, identified as the available terminus closer to the electron transfer region. We also neutralized an anionic patch surrounding the interface Fe-S cluster to improve transfer kinetics with the negatively charged ferredoxin. Initial screening showed the enzyme tolerated both truncation and charge neutralization on the small subunit ferredoxin-binding face. While the enzyme activity was relatively unchanged using the substrate methyl viologen, we observed a marked improvement from both the ferredoxin fusion and surface modification using only dithionite as an electron donor. Combining ferredoxin fusion and surface charge modification showed progressively improved activity in an in vitro assay with purified enzyme.

Transfer and concentration factors in laboratory and environmental conditions

International Nuclear Information System (INIS)

Paschoa, A.S.; Amaral, E.C.S.

1993-01-01

Environmental transfer factors, as well as concentration and accumulation factors, have been increasingly used in environmental dosimetric models. These models are often the basis for decision-making processes concerning radiological protection. However, the uncertainties associated with measured and default values of transfer and concentration factors are usually not taken into account in the decision making processes. In addition, laboratory-based values for these factors do not necessarily agree with site-specific and species-specific transfer and concentration factors. Soil-to-plant transfer factors and water-to-aquatic-organisms concentration factors are not only time and concentration-dependent, but also species-and site-specific environment-dependent. These uncertainties and dependencies may make the decision-making process, based on models, quite a difficult exercise. The current work examines, as an example, the time-dependent variations in the accumulation of 226 Ra in zooplankton in a laboratory experiment as compared with the concentration factor measured in a natural environment. In addition, the work reviews differences in 228 Ra and 226 Ra concentration factors for several plant families measured in a highly radioactive environment. (author). 9 refs, 3 figs, 3 tabs

Heat transfer and critical heat flux in a asymmetrically heated tube helicoidal flow

International Nuclear Information System (INIS)

Boscary, J.

1995-10-01

The design of plasma facing components is crucial for plasma performance in next fusion reactors. These elements will be submitted to very high heat flux. They will be actively water-cooled by swirl tubes in the subcooled boiling regime. High heat flux experiments were conducted in order to analyse the heat transfer and to evaluate the critical heat flux. Water-cooled mock-ups were one-side heated by an electron beam gun for different thermal-hydraulic conditions. The critical heat flux was detected by an original method based on the isotherm modification on the heated surface. The wall heat transfer law including forced convection and subcooled boiling regimes was established. Numerical calculations of the material heat transfer conduction allowed the non-homogeneous distribution of the wall temperature and of the wall heat flux to be evaluated. The critical heat flux value was defined as the wall maximum heat flux. A critical heat flux model based on the liquid sublayer dryout under a vapor blanket was established. A good agreement with test results was found. (author). 198 refs., 126 figs., 21 tabs

Reliably measuring the condition of mineral-based transfer fluids using a permittivity sensor – practical application to thermal fluid heat transfer

Directory of Open Access Journals (Sweden)

Christopher Ian Wright

2015-09-01

Full Text Available This article describes a series of experiments to assess the performance and suitability of a permittivity sensor in the area of heat transfer. The permittivity sensor measures condition index and temperature of a fluid. A series of 5 experiments was conducted. They assessed the reproducibility of the sensor using both clean and dirty fluid samples, and showed the sensor had good reproducibility based on calculations of coefficients of variation. The sensor also detected water contamination, assessed from construction of a stimulus-response curve to step-wise increases in water and from real-life samples where water content was reported to be out of specification. Further experiments tested the association between condition index and both water content and fluid cleanliness in a real-life setting. Results demonstrated the sensor that condition index reflected changes in fluid water and cleanliness and was therefore a measure of fluid condition. The implication of these findings is that the sensor can be used to make rapid and reliable assessments of fluid condition using only small samples (i.e., <50 ml. The sensor may be of benefit to customers that need to make a lot of regular samples over a large processing site, such as concentrated solar power plants.

Conditional Lyapunov exponents and transfer entropy in coupled bursting neurons under excitation and coupling mismatch

Science.gov (United States)

Soriano, Diogo C.; Santos, Odair V. dos; Suyama, Ricardo; Fazanaro, Filipe I.; Attux, Romis

2018-03-01

This work has a twofold aim: (a) to analyze an alternative approach for computing the conditional Lyapunov exponent (λcmax) aiming to evaluate the synchronization stability between nonlinear oscillators without solving the classical variational equations for the synchronization error dynamical system. In this first framework, an analytic reference value for λcmax is also provided in the context of Duffing master-slave scenario and precisely evaluated by the proposed numerical approach; (b) to apply this technique to the study of synchronization stability in chaotic Hindmarsh-Rose (HR) neuronal models under uni- and bi-directional resistive coupling and different excitation bias, which also considered the root mean square synchronization error, information theoretic measures and asymmetric transfer entropy in order to offer a better insight of the synchronization phenomenon. In particular, statistical and information theoretical measures were able to capture similarity increase between the neuronal oscillators just after a critical coupling value in accordance to the largest conditional Lyapunov exponent behavior. On the other hand, transfer entropy was able to detect neuronal emitter influence even in a weak coupling condition, i.e. under the increase of conditional Lyapunov exponent and apparently desynchronization tendency. In the performed set of numerical simulations, the synchronization measures were also evaluated for a two-dimensional parameter space defined by the neuronal coupling (emitter to a receiver neuron) and the (receiver) excitation current. Such analysis is repeated for different feedback couplings as well for different (emitter) excitation currents, revealing interesting characteristics of the attained synchronization region and conditions that facilitate the emergence of the synchronous behavior. These results provide a more detailed numerical insight of the underlying behavior of a HR in the excitation and coupling space, being in accordance

POSTRANSLATIONAL MODIFICATIONS OF P53: UPSTREAM SIGNALING PATHWAYS.

Energy Technology Data Exchange (ETDEWEB)

ANDERSON,C.W.APPELLA,E.

2003-10-23

The p53 tumor suppressor is a tetrameric transcription factor that is posttranslational modified at >20 different sites by phosphorylation, acetylation, or sumoylation in response to various cellular stress conditions. Specific posttranslational modifications, or groups of modifications, that result from the activation of different stress-induced signaling pathways are thought to modulate p53 activity to regulate cell fate by inducing cell cycle arrest, apoptosis, or cellular senescence. Here we review recent progress in characterizing the upstream signaling pathways whose activation in response to various genotoxic and non-genotoxic stresses result in p53 posttranslational modifications.

Energy transfer in Anabaena variabilis filaments adapted to nitrogen-depleted and nitrogen-enriched conditions studied by time-resolved fluorescence.

Science.gov (United States)

Onishi, Aya; Aikawa, Shimpei; Kondo, Akihiko; Akimoto, Seiji

2017-09-01

Nitrogen is among the most important nutritious elements for photosynthetic organisms such as plants, algae, and cyanobacteria. Therefore, nitrogen depletion severely compromises the growth, development, and photosynthesis of these organisms. To preserve their integrity under nitrogen-depleted conditions, filamentous nitrogen-fixing cyanobacteria reduce atmospheric nitrogen to ammonia, and self-adapt by regulating their light-harvesting and excitation energy-transfer processes. To investigate the changes in the primary processes of photosynthesis, we measured the steady-state absorption and fluorescence spectra and time-resolved fluorescence spectra (TRFS) of whole filaments of the nitrogen-fixing cyanobacterium Anabaena variabilis at 77 K. The filaments were grown in standard and nitrogen-free media for 6 months. The TRFS were measured with a picosecond time-correlated single photon counting system. Despite the phycobilisome degradation, the energy-transfer paths within phycobilisome and from phycobilisome to both photosystems were maintained. However, the energy transfer from photosystem II to photosystem I was suppressed and a specific red chlorophyll band appeared under the nitrogen-depleted condition.

Analysis of heat transfer regulation and modification employing intermittently emplaced porous cavities

International Nuclear Information System (INIS)

Vafai, K.; Huang, P.C.

1994-01-01

The present work forms a fundamental investigation on the effects of using intermittently porous cavities for regulating and modifying the flow and temperature fields and therefore changing the skin friction and heat transfer characteristics of an external surface. A general flow model that accounts for the effects of the impermeable boundary and inertial effects is used to describe the flow inside the porous region. Solutions of the problem have been carried out using a finite-difference method through the use of a stream function-vorticity transformation. Various interesting characteristics of the flow and temperature fields in the composite layer are analyzed and discussed in detail. The effects of various governing dimensionless parameters, such as the Darcy number, Reynolds number, Prandtl number, the inertia parameter as well as the effects of pertinent geometric parameters are thoroughly explored. Furthermore, the interactive effects of the embedded porous substrates on skin friction and heat transfer characteristics of an external surface are analyzed. The configuration analyzed in this work provides an innovative approach in altering the frictional and heat transfer characteristics of an external surface. 27 refs., 12 figs., 1 tab

Situation Selection and Modification for Emotion Regulation in Younger and Older Adults.

Science.gov (United States)

Livingstone, Kimberly M; Isaacowitz, Derek M

2015-11-01

This research investigated age differences in use and effectiveness of situation selection and situation modification for emotion regulation. Socioemotional selectivity theory suggests stronger emotional well-being goals in older age; emotion regulation may support this goal. Younger and older adults assigned to an emotion regulation or "just view" condition first freely chose to engage with negative, neutral, or positive material (situation selection), then chose to view or skip negative and positive material (situation modification), rating affect after each experience. In both tasks, older adults in both goal conditions demonstrated pro-hedonic emotion regulation, spending less time with negative material compared to younger adults. Younger adults in the regulate condition also engaged in pro-hedonic situation selection, but not modification. Whereas situation selection was related to affect, modification of negative material was not. This research supports more frequent pro-hedonic motivation in older age, as well as age differences in use of early-stage emotion regulation.

Restriction-modification systems in Mycoplasma spp

Directory of Open Access Journals (Sweden)

Marcelo Brocchi

2007-01-01

Full Text Available Restriction and Modification (R-M systems are present in all Mycoplasma species sequenced so far. The presence of these genes poses barriers to gene transfer and could protect the cell against phage infections. The number and types of R-M genes between different Mycoplasma species are variable, which is characteristic of a polymorphism. The majority of the CDSs code for Type III R-M systems and particularly for methyltransferase enzymes, which suggests that functions other than the protection against the invasion of heterologous DNA may exist. A possible function of these enzymes could be the protection against the invasion of other but similar R-M systems. In Mycoplasma hyopneumoniae strain J, three of the putative methyltransferase genes were clustered in a region forming a genomic island. Many R-M CDSs were mapped in the vicinity of transposable elements suggesting an association between these genes and reinforcing the idea of R-M systems as mobile selfish DNA. Also, many R-M genes present repeats within their coding sequences, indicating that their expression is under the control of phase variation mechanisms. Altogether, these data suggest that R-M systems are a remarkable characteristic of Mycoplasma species and are probably involved in the adaptation of these bacteria to different environmental conditions.

The simulation calculation of acoustics energy transfer through the material structure

Directory of Open Access Journals (Sweden)

Zvolenský Peter

2016-01-01

Full Text Available The paper deals with the modification of the rail passenger coach floor design aimed at improvement of sound reduction index. Refurbishing was performed by using a new acoustic material with a filamentary microstructure. The materials proposed in research were compared by simulation calculation of acoustic energy transfer trough porous microstructure of filamentary material, and the effect of material porosity on sound reduction index and sound absorption coefficient were observed. This proposed filamentary material can be used in the railway bed structure, too. High degree of noise absorbing, resistance to climate conditions, low specific mass, enable to choose a system of low anti-noise barriers having similar properties as standard high anti-noise walls..

Heat exchanger network retrofit optimization involving heat transfer enhancement

International Nuclear Information System (INIS)

Wang Yufei; Smith, Robin; Kim, Jin-Kuk

2012-01-01

Heat exchanger network retrofit plays an important role in energy saving in process industry. Many design methods for the retrofit of heat exchanger networks have been proposed during the last three decades. Conventional retrofit methods rely heavily on topology modifications which often result in a long retrofit duration and high initial costs. Moreover, the addition of extra surface area to the heat exchanger can prove difficult due to topology, safety and downtime constraints. Both of these problems can be avoided through the use of heat transfer enhancement in heat exchanger network retrofit. This paper presents a novel design approach to solve heat exchanger network retrofit problems based on heat transfer enhancement. An optimisation method based on simulated annealing has been developed to find the appropriate heat exchangers to be enhanced and to calculate the level of enhancement required. The physical insight of enhanced exchangers is also analysed. The new methodology allows several possible retrofit strategies using different retrofit methods be determined. Comparison of these retrofit strategies demonstrates that retrofit modification duration and payback time are reduced when heat transfer enhancement is utilised. Heat transfer enhancement can be also used as a substitute for increased heat exchanger network surface area to reduce retrofit investment costs.

Measuring of heat transfer coefficient

DEFF Research Database (Denmark)

Henningsen, Poul; Lindegren, Maria

Subtask 3.4 Measuring of heat transfer coefficient Subtask 3.4.1 Design and setting up of tests to measure heat transfer coefficient Objective: Complementary testing methods together with the relevant experimental equipment are to be designed by the two partners involved in order to measure...... the heat transfer coefficient for a wide range of interface conditions in hot and warm forging processes. Subtask 3.4.2 Measurement of heat transfer coefficient The objective of subtask 3.4.2 is to determine heat transfer values for different interface conditions reflecting those typically operating in hot...

CONDITIONS FOR TECHNOLOGY TRANSFER IN THE AGRICULTURE OF CONGO REPUBLIC*

Directory of Open Access Journals (Sweden)

Katarzyna Andrzejczak

2017-03-01

Full Text Available The majority of the population in Sub-Saharan Africa is employed in agriculture. Nevertheless, the productivity of the sector is relatively low in comparison with other regions of the world. Based on convergence theory, technology transfer can enhance growth. However, the effective transfer of technology requires a certain absorption capacity from the recipient. Based on the qualitative research on cassava production in Congo Brazzaville, we identified key factors that influence the transfer process. These factors have been divided into four key areas: market, institutions, technology, and social capability. Cassava production value chain in Ignie region served as a case study for the evaluation of technology transfer absorptive capacity in Congo agriculture. We learned that the lack of agro-technical education, shortages in infrastructure, unavailability of business services, and market structure are among the main barriers of the intensification of technology use in agriculture.

A novel post-translational modification in nerve terminals: O-linked N-acetylglucosamine phosphorylation

DEFF Research Database (Denmark)

Graham, Mark E; Thaysen-Andersen, Morten; Bache, Nicolai

2011-01-01

Protein phosphorylation and glycosylation are the most common post-translational modifications observed in biology, frequently on the same protein. Assembly protein AP180 is a synapse-specific phosphoprotein and O-linked beta-N-acetylglucosamine (O-GlcNAc) modified glycoprotein. AP180 is involved......NAc-P to a Thr residue was confirmed by electron transfer dissociation MS. A second AP180 tryptic peptide was also glycosyl phosphorylated, but the site of modification was not assigned. Sequence similarities suggest there may be a common motif within AP180 involving glycosyl phosphorylation and dual flanking...... phosphorylation sites within 4 amino acid residues. This novel type of protein glycosyl phosphorylation adds a new signaling mechanism to the regulation of neurotransmission and more complexity to the study of O-GlcNAc modification....

Modelling 3H and 14C transfer to farm animals and their products under steady state conditions

International Nuclear Information System (INIS)

Galeriu, D.; Melintescu, A.; Beresford, N.A.; Crout, N.M.J.; Peterson, R.; Takeda, H.

2007-01-01

The radionuclides 14 C and 3 H may both be released from nuclear facilities. These radionuclides are unusual, in that they are isotopes of macro-elements which form the basis of animal tissues, feed and, in the case of 3 H, water. There are few published values describing the transfer of 3 H and 14 C from feed to animal derived food products under steady state conditions. Approaches are described which enable the prediction of 14 C and 3 H transfer parameter values from readily available information on the stable H or C concentration of animal feeds, tissues and milk, water turnover rates, and feed intakes and digestibilities. We recommend that the concentration ratio between feed and animal product activity concentrations be used as it is less variable than the transfer coefficient (ratio between radionuclide activity concentration in animal milk or tissue to the daily intake of a radionuclide)

Numerical analysis of fractional MHD Maxwell fluid with the effects of convection heat transfer condition and viscous dissipation

Directory of Open Access Journals (Sweden)

Yu Bai

2017-12-01

Full Text Available This paper investigates the incompressible fractional MHD Maxwell fluid due to a power function accelerating plate with the first order slip, and the numerical analysis on the flow and heat transfer of fractional Maxwell fluid has been done. Moreover the deformation motion of fluid micelle is simply analyzed. Nonlinear velocity equation are formulated with multi-term time fractional derivatives in the boundary layer governing equations, and convective heat transfer boundary condition and viscous dissipation are both taken into consideration. A newly finite difference scheme with L1-algorithm of governing equations are constructed, whose convergence is confirmed by the comparison with analytical solution. Numerical solutions for velocity and temperature show the effects of pertinent parameters on flow and heat transfer of fractional Maxwell fluid. It reveals that the fractional derivative weakens the effects of motion and heat conduction. The larger the Nusselt number is, the greater the heat transfer capacity of fluid becomes, and the temperature gradient at the wall becomes more significantly. The lower Reynolds number enhances the viscosity of the fluid because it is the ratio of the viscous force and the inertia force, which resists the flow and heat transfer.

Numerical analysis of fractional MHD Maxwell fluid with the effects of convection heat transfer condition and viscous dissipation

Science.gov (United States)

Bai, Yu; Jiang, Yuehua; Liu, Fawang; Zhang, Yan

2017-12-01

This paper investigates the incompressible fractional MHD Maxwell fluid due to a power function accelerating plate with the first order slip, and the numerical analysis on the flow and heat transfer of fractional Maxwell fluid has been done. Moreover the deformation motion of fluid micelle is simply analyzed. Nonlinear velocity equation are formulated with multi-term time fractional derivatives in the boundary layer governing equations, and convective heat transfer boundary condition and viscous dissipation are both taken into consideration. A newly finite difference scheme with L1-algorithm of governing equations are constructed, whose convergence is confirmed by the comparison with analytical solution. Numerical solutions for velocity and temperature show the effects of pertinent parameters on flow and heat transfer of fractional Maxwell fluid. It reveals that the fractional derivative weakens the effects of motion and heat conduction. The larger the Nusselt number is, the greater the heat transfer capacity of fluid becomes, and the temperature gradient at the wall becomes more significantly. The lower Reynolds number enhances the viscosity of the fluid because it is the ratio of the viscous force and the inertia force, which resists the flow and heat transfer.

Improvement of the RELAP5 subcooled boiling model for low pressure conditions

International Nuclear Information System (INIS)

Koncar, B.; Mavko, B.

2000-01-01

The RELAP5/MOD3.2.2 Gamma code was assessed against low pressure subcooled boiling experiments performed by Zeitoun and Shoukri [1] in a vertical annulus. The predictions of subcooled boiling bubbly flow showed that the present version of the RELAP5 code underestimates the void fraction growth along the tube. To improve the void fraction prediction at low pressure conditions a set of model changes is proposed, which includes modifications of bubbly-slug transition criterion, drift-flux model, interphase heat transfer coefficient and wall evaporation modeling. The improved experiment predictions with the modified RELAP5 code are presented and analysed. (author)

Identification of histone modifications in biomedical text for supporting epigenomic research.

Science.gov (United States)

Kolárik, Corinna; Klinger, Roman; Hofmann-Apitius, Martin

2009-01-30

Posttranslational modifications of histones influence the structure of chromatine and in such a way take part in the regulation of gene expression. Certain histone modification patterns, distributed over the genome, are connected to cell as well as tissue differentiation and to the adaption of organisms to their environment. Abnormal changes instead influence the development of disease states like cancer. The regulation mechanisms for modifying histones and its functionalities are the subject of epigenomics investigation and are still not completely understood. Text provides a rich resource of knowledge on epigenomics and modifications of histones in particular. It contains information about experimental studies, the conditions used, and results. To our knowledge, no approach has been published so far for identifying histone modifications in text. We have developed an approach for identifying histone modifications in biomedical literature with Conditional Random Fields (CRF) and for resolving the recognized histone modification term variants by term standardization. For the term identification F1 measures of 0.84 by 10-fold cross-validation on the training corpus and 0.81 on an independent test corpus have been obtained. The standardization enabled the correct transformation of 96% of the terms from training and 98% from test the corpus. Due to the lack of terminologies exhaustively covering specific histone modification types, we developed a histone modification term hierarchy for use in a semantic text retrieval system. The developed approach highly improves the retrieval of articles describing histone modifications. Since text contains context information about performed studies and experiments, the identification of histone modifications is the basis for supporting literature-based knowledge discovery and hypothesis generation to accelerate epigenomic research.

Investigation of Advanced Counterrotation Blade Configuration Concepts for High Speed Turboprop Systems. Task 8: Cooling Flow/heat Transfer Analysis User's Manual

Science.gov (United States)

Hall, Edward J.; Topp, David A.; Heidegger, Nathan J.; Delaney, Robert A.

1994-01-01

The focus of this task was to validate the ADPAC code for heat transfer calculations. To accomplish this goal, the ADPAC code was modified to allow for a Cartesian coordinate system capability and to add boundary conditions to handle spanwise periodicity and transpiration boundaries. This user's manual describes how to use the ADPAC code as developed in Task 5, NAS3-25270, including the modifications made to date in Tasks 7 and 8, NAS3-25270.

A fluid-solid coupling simulation method for convection heat transfer coefficient considering the under-vehicle condition

Science.gov (United States)

Tian, C.; Weng, J.; Liu, Y.

2017-11-01

The convection heat transfer coefficient is one of the evaluation indexes of the brake disc performance. The method used in this paper to calculate the convection heat transfer coefficient is a fluid-solid coupling simulation method, because the calculation results through the empirical formula method have great differences. The model, including a brake disc, a car body, a bogie and flow field, was built, meshed and simulated in the software FLUENT. The calculation models were K-epsilon Standard model and Energy model. The working condition of the brake disc was considered. The coefficient of various parts can be obtained through the method in this paper. The simulation result shows that, under 160 km/h speed, the radiating ribs have the maximum convection heat transfer coefficient and the value is 129.6W/(m2·K), the average coefficient of the whole disc is 100.4W/(m2·K), the windward of ribs is positive-pressure area and the leeward of ribs is negative-pressure area, the maximum pressure is 2663.53Pa.

PRAGMATIC TRANSFER IN REQUEST REALIZATIONS

Directory of Open Access Journals (Sweden)

Indawan Syahri

2007-01-01

Full Text Available This study investigates the pragmatic transfer in English request realizations made by EFL learners, i.e. the proficient learners. The subjects were students of an English Study Program who obtained TOEFL-like scores of at least 450. The data were collected by means of DCT-questionnaires and Role-plays. The results show that the subjects realize requests in the form of external modifications more frequently. Most of them embed their requests with supportive moves dominantly. They enfold the acts with the moves before, after or in both positions. Of the three positions, they mostly insert the moves initial position, i.e., through inductive patterns. This is due to pragmatic transfer.

Flow instability research on steam generator with straight double-walled heat transfer tube for FBR. Pressure drop under high pressure condition

International Nuclear Information System (INIS)

Liu, Wei; Tamai, Hidesada; Yoshida, Hiroyuki; Takase, Kazuyuki; Hayafune, Hiroki; Futagami, Satoshi; Kisohara, Naoyuki

2008-01-01

For the Steam Generator (SG) with straight double-walled heat transfer tube that used in sodium cooled Faster Breeder Reactor, flow instability is one of the most important items need researching. As the first step of the research, thermal hydraulics experiments were performed under high pressure condition in JAEA with using a straight tube. Pressure drop, heat transfer coefficients and void fraction data were derived. This paper evaluates the pressure drop data with TRAC-BF1 code. The Pffan's correlation for single phase flow and the Martinelli-Nelson's two-phase flow multiplier are found can be well predicted the present pressure drop data under high pressure condition. (author)

Wealth differentials in the impact of conditional and unconditional cash transfers on education: findings from a community-randomised controlled trial in Zimbabwe.

Science.gov (United States)

Fenton, Rory; Nyamukapa, Constance; Gregson, Simon; Robertson, Laura; Mushati, Phyllis; Thomas, Ranjeeta; Eaton, Jeffrey W

2016-12-01

We investigated (1) how household wealth affected the relationship between conditional cash transfers (CCT) and unconditional cash transfers (UCT) and school attendance, (2) whether CCT and UCT affected educational outcomes (repeating a year of school), (3) if baseline school attendance and transfer conditions affected how much of the transfers participants spent on education and (4) if CCT or UCT reduced child labour in recipient households. Data were analysed from a cluster-randomized controlled trial of CCT and UCT in 4043 households from 2009 to 2010. Recipient households received $18 dollars per month plus $4 per child. CCT were conditioned on above 80% school attendance, a full vaccination record and a birth certificate. In the poorest quintile, the odds ratio of above 80% school attendance at follow-up for those with below 80% school attendance at baseline was 1.06 (p = .67) for UCT vs. CCT. UCT recipients reported spending slightly more (46.1% (45.4-46.7)) of the transfer on school expenses than did CCT recipients (44.8% (44.1-45.5)). Amongst those with baseline school attendance of below 80%, there was no statistically significant difference between CCT and UCT participants in the proportion of the transfer spent on school expenses (p = .63). Amongst those with above 80% baseline school attendance, CCT participants spent 3.5% less (p = .001) on school expenses than UCT participants. UCT participants were no less likely than those in the control group to repeat a grade of school. CCT participants had .69 (.60-.79) lower odds vs. control of repeating the previous school grade. Children in CCT recipient households spent an average of .31 fewer hours in paid work than those in the control group (p control arm (p = .06).

Genetic modification of hematopoietic stem cells with nonviral systems: past progress and future prospects.

Science.gov (United States)

Papapetrou, E P; Zoumbos, N C; Athanassiadou, A

2005-10-01

Serious unwanted complications provoked by retroviral gene transfer into hematopoietic stem cells (HSCs) have recently raised the need for the development and assessment of alternative gene transfer vectors. Within this context, nonviral gene transfer systems are attracting increasing interest. Their main advantages include low cost, ease of handling and large-scale production, large packaging capacity and, most importantly, biosafety. While nonviral gene transfer into HSCs has been restricted in the past by poor transfection efficiency and transient maintenance, in recent years, biotechnological developments are converting nonviral transfer into a realistic approach for genetic modification of cells of hematopoietic origin. Herein we provide an overview of past accomplishments in the field of nonviral gene transfer into hematopoietic progenitor/stem cells and we point at future challenges. We argue that episomally maintained self-replicating vectors combined with physical methods of delivery show the greatest promise among nonviral gene transfer strategies for the treatment of disorders of the hematopoietic system.

Heat transfer and critical heat flux in a spiral flow in an asymmetrical heated tube

International Nuclear Information System (INIS)

Boscary, J.; Association Euratom-CEA, Centre d'Etudes Nucleaires de Cadarache, 13 - Saint-Paul-lez-Durance

1997-03-01

The design of plasma facing components is crucial for plasma performance in next fusion reactors. These elements will be submitted to very high heat flux. They will be actively water-cooled by swirl tubes in the subcooled boiling regime. High heat flux experiments were conducted in order to analyse the heat transfer and to evaluate the critical heat flux. Water-cooled mock-ups were one-side heated by an electron beam gun for different thermal-hydraulic conditions. The critical heat flux was detected by an original method based on the isotherm modification on the heated surface. The wall heat transfer law including forced convection and subcooled boiling regimes was established. Numerical calculations of the material heat transfer conduction allowed the non-homogeneous distribution of the wall temperature and of the wall heat flux to be evaluated. The critical heat flux value was defined as the wall maximum heat flux. A critical heat flux model based on the liquid sublayer dryout under a vapor blanket was established. A good agreement with test results was found. (author)

Transfer of radionuclides to vegetable and other crops grown on land reclaimed from the sea

International Nuclear Information System (INIS)

Green, N.; Wilkins, B.T.

1995-01-01

An area of reclaimed land on the Lancashire coast has been used to grow a wide range of crops to provide data on transfer parameters of radionuclides in foodchains when the activity is almost entirely of marine origin. Activity concentrations in the foodstuffs were low and not of radiological significance. However, meaningful results could be obtained if large sample sizes were employed. This paper sets out the methodology applied to a substantial field investigation of transfer to vegetable crops. The large sample sizes could be accommodated adequately with only minor modifications to established analytical procedures. The results of the study are discussed briefly. Since the growing conditions were virtually identical for each crop, comparisons of transfer factors between the different crops should therefore be valid. For some radionuclides, notably 239,240 Pu, 241 Am and 99 Tc, the work has added significantly to the data that are presently available. For most of the radionuclides studied, uptake by crops could be adequately predicted using the parameter values currently used in generic assessments, but for 99 Tc, lower values would be more appropriate

Analytical Solution of Heat Conduction for Hollow Cylinders with Time-Dependent Boundary Condition and Time-Dependent Heat Transfer Coefficient

Directory of Open Access Journals (Sweden)

Te-Wen Tu

2015-01-01

Full Text Available An analytical solution for the heat transfer in hollow cylinders with time-dependent boundary condition and time-dependent heat transfer coefficient at different surfaces is developed for the first time. The methodology is an extension of the shifting function method. By dividing the Biot function into a constant plus a function and introducing two specially chosen shifting functions, the system is transformed into a partial differential equation with homogenous boundary conditions only. The transformed system is thus solved by series expansion theorem. Limiting cases of the solution are studied and numerical results are compared with those in the literature. The convergence rate of the present solution is fast and the analytical solution is simple and accurate. Also, the influence of physical parameters on the temperature distribution of a hollow cylinder along the radial direction is investigated.

Cluster transfer form factor and intercluster relative motion in the orthogonality-condition model

International Nuclear Information System (INIS)

Lovas, R.G.; Pal, K.F.

1984-01-01

The orthogonality-condition model (OCM), as an approximation method for calculating the overlap and potential overlap functions involved in the form factor of transfer reactions, is tested against microscopic cluster calculations for the 7 Li=α+t system. The OCM overlap and potential overlap turned out to depend strongly on the OCM potential although the potentials are chosen so as to produce the same asymptotic phase. Excellent approximations to microscopic overlaps and potential overlaps are, however, obtained by optimizing the OCM potential so that the OCM may reproduce the microscopic energy surface. This way the dependence on the OCM potential is traced back to the underlying nucleon-nucleon force. (author)

RELAP5/MOD2 code modifications to obtain better predictions for the once-through steam generator

International Nuclear Information System (INIS)

Blanchat, T.; Hassan, Y.

1989-01-01

The steam generator is a major component in pressurized water reactors. Predicting the response of a steam generator during both steady-state and transient conditions is essential in studying the thermal-hydraulic behavior of a nuclear reactor coolant system. Therefore, many analytical and experimental efforts have been performed to investigate the thermal-hydraulic behavior of the steam generators during operational and accident transients. The objective of this study is to predict the behavior of the secondary side of the once-through steam generator (OTSG) using the RELAP5/MOD2 computer code. Steady-state conditions were predicted with the current version of the RELAP5/MOD2 code and compared with experimental plant data. The code predictions consistently underpredict the degree of superheat. A new interface friction model has been implemented in a modified version of RELAP5/MOD2. This modification, along with changes to the flow regime transition criteria and the heat transfer correlations, correctly predicts the degree of superheat and matches plant data

Surface modification and electrochemical behaviour of undoped nanodiamonds

International Nuclear Information System (INIS)

Zang Jianbing; Wang Yanhui; Bian Linyan; Zhang Jinhui; Meng Fanwei; Zhao Yuling; Ren Shubin; Qu Xuanhui

2012-01-01

Surface modifications of undoped nanodiamond (ND) particles were carried out through different annealing treatments. The methods of Fourier transform infrared spectroscopy, Raman spectroscopy, and transmission electron microscopy were used to characterize the ND surface before and after the annealing process. The electrochemical properties of the modified ND powders in aqueous solution were investigated with Fe(CN) 6 3−/4− as a redox probe. When the annealing temperature was below 850 °C, vacuum annealing removed parts of the oxygen-containing surface functionalities from the ND surface and produced more sp 2 carbon atoms in the shell. The charge transfer of the Fe(CN) 6 3−/4− redox couple decreased with increasing annealing temperature. Re-annealing in air restored the original surface conditions: few sp 2 -bonded carbon atoms and similar surface functionalities, and thus the electrochemical activity. When ND was annealed in vacuum at 900–1100 °C, more serious graphitization produced a continuous fullerenic shell wrapped around a diamond core, which had a high conductivity and electrochemical activity. This provides a novel nanoparticle with high conductivity and high stability for electrochemical applications.

A matheuristic for transfer synchronization through integrated timetabling and vehicle scheduling

DEFF Research Database (Denmark)

Fonseca, João Paiva; van der Hurk, Evelien; Roberti, Roberto

2018-01-01

Long transfer times often add unnecessary inconvenience to journeys in public transport systems. Synchronizing relevant arrival and departure times through small timetable modifications could reduce excess transfer times, but may also directly affect the operational costs, as the timetable defines...... the set of feasible vehicle schedules. Therefore better results in terms of passenger service, operational costs, or both, could be obtained by solving these problems simultaneously....

Operating test report for project W-417, T-plant steam removal upgrade, waste transfer portion

International Nuclear Information System (INIS)

Myers, N.K.

1997-01-01

This Operating Test Report (OTR) documents the performance results of the Operating Test Procedure HNF-SD-W417-OTP-001 that provides steps to test the waste transfer system installed in the 221-T Canyon under project W-417. Recent modifications have been performed on the T Plant Rail Car Waste Transfer System. This Operating Test Procedure (OTP) will document the satisfactory operation of the 221-T Rail Car Waste Transfer System modified by project W-417. Project W-417 installed a pump in Tank 5-7 to replace the steam jets used for transferring liquid waste. This testing is required to verify that operational requirements of the modified transfer system have been met. Figure 2 and 3 shows the new and existing system to be tested. The scope of this testing includes the submersible air driven pump operation in Tank 5-7, liquid waste transfer operation from Tank 5-7 to rail car (HO-IOH-3663 or HO-IOH-3664), associated line flushing, and the operation of the flow meter. This testing is designed to demonstrate the satisfactory operation-of the transfer line at normal operating conditions and proper functioning of instruments. Favorable results will support continued use of this system for liquid waste transfer. The Functional Design Criteria for this system requires a transfer flow rate of 40 gallons per minute (GPM). To establish these conditions the pump will be supplied up to 90 psi air pressure from the existing air system routed in the canyon. An air regulator valve will regulate the air pressure. Tank capacity and operating ranges are the following: Tank No. Capacity (gal) Operating Range (gal) 5-7 10,046 0 8040 (80%) Rail car (HO-IOH-3663 HO-IOH-3664) 097219,157 Existing Tank level instrumentation, rail car level detection, and pressure indicators will be utilized for acceptance/rejection Criteria. The flow meter will be verified for accuracy against the Tank 5-7 level indicator. The level indicator is accurate to within 2.2 %. This will be for information only

Effect of carbon nanofiber surface morphology on convective heat transfer from cylindrical surface: Synthesis, characterization and heat transfer measurement

NARCIS (Netherlands)

Taha, T.J.; Mojet, Barbara; Lefferts, Leonardus; van der Meer, Theodorus H.

2016-01-01

In this work, heat transfer surface modification is made by layers of carbon nanofiber (CNF) on a 50 μm nickel wire using Thermal chemical vapor deposition process (TCVD). Three different CNF layer morphologies are made, at 500 °C, 600 °C and 700 °C, to investigate the influence of morphology on

RNA polymerase II transcriptional fidelity control and its functional interplay with DNA modifications

Science.gov (United States)

Xu, Liang; Wang, Wei; Chong, Jenny; Shin, Ji Hyun; Xu, Jun; Wang, Dong

2016-01-01

Accurate genetic information transfer is essential for life. As a key enzyme involved in the first step of gene expression, RNA polymerase II (Pol II) must maintain high transcriptional fidelity while it reads along DNA template and synthesizes RNA transcript in a stepwise manner during transcription elongation. DNA lesions or modifications may lead to significant changes in transcriptional fidelity or transcription elongation dynamics. In this review, we will summarize recent progress towards understanding the molecular basis of RNA Pol II transcriptional fidelity control and impacts of DNA lesions and modifications on Pol II transcription elongation. PMID:26392149

Heat Transfer Analysis and Modification of Thermal Probe for Gas-Solid Measurement

Directory of Open Access Journals (Sweden)

Hong Zhang

2016-01-01

Full Text Available The presented work aims to measure the gas-solid two-phase mass flow-rate in pneumatic conveyor, and a novel modified thermal probe is applied. A new analysis of the local heat transfer coefficients of thermal probe is presented, while traditional investigations focus on global coefficients. Thermal simulations are performed in Fluent 6.2 and temperature distributions of the probe are presented. The results indicate that the probe has obviously stable and unstable heat transfer areas. Based on understanding of probe characteristics, a modified probe structure is designed, which makes the probe output signal more stable and widens the measuring range. The experiments are carried out in a special designed laboratory scale pneumatic conveyor, and the modified probe shows an unambiguous improvement of the performance compared with the traditional one.

Configuration management of plant modifications for nuclear power plants

International Nuclear Information System (INIS)

Ritsch, W.J.

1987-01-01

Due to the increasing complexity of nuclear power plant operation, regulatory pressure, and the large numbers of people required to operate and support the stations, the control of plant modifications at these plants needs to be expanded and improved. The aerospace and defense industries, as well as the owners or operators of large energy projects have established configuration management programs (CMPs) to control plant design changes. These programs are composed of well-defined functions for identifying, evaluating, recording, tracking, issuing, and documenting the established baseline conditions, as well as required changes to these baseline conditions. The purpose of this paper is to describe a recommended CMP for plant modifications consisting of a computerized data base installed on the utility's computer to provide a central storage of plant design and operations data necessary to control the following activities as they are affected by plant design changes: training; record management; operations; maintenance; health physics; planning/scheduling; procurement/inventory control; outage management (including modifications); and emergency response

Heat transfer

International Nuclear Information System (INIS)

Saad, M.A.

1985-01-01

Heat transfer takes place between material systems as a result of a temperature difference. The transmission process involves energy conversions governed by the first and second laws of thermodynamics. The heat transfer proceeds from a high-temperature region to a low-temperature region, and because of the finite thermal potential, there is an increase in entropy. Thermodynamics, however, is concerned with equilibrium states, which includes thermal equilibrium, irrespective of the time necessary to attain these equilibrium states. But heat transfer is a result of thermal nonequilibrium conditions, therefore, the laws of thermodynamics alone cannot describe completely the heat transfer process. In practice, most engineering problems are concerned with the rate of heat transfer rather than the quantity of heat being transferred. Resort then is directed to the particular laws governing the transfer of heat. There are three distinct modes of heat transfer: conduction, convection, and radiation. Although these modes are discussed separately, all three types may occur simultaneously

A new correlation for convective heat transfer coefficient of water–alumina nanofluid in a square array subchannel under PWR condition

Energy Technology Data Exchange (ETDEWEB)

Shamim, Jubair A. [Department of Nuclear Engineering, Seoul National University, Seoul 08826 (Korea, Republic of); Department of Mechanical Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan); Bhowmik, Palash K. [Department of Nuclear Engineering, Seoul National University, Seoul 08826 (Korea, Republic of); Department of Nuclear Engineering, Missouri University of Science and Technology, 1201 N. State St., Rolla, MO 65409 (United States); Xiangyi, Chen [Department of Nuclear Engineering, Seoul National University, Seoul 08826 (Korea, Republic of); Suh, Kune Y., E-mail: kysuh@snu.ac.kr [Department of Nuclear Engineering, Seoul National University, Seoul 08826 (Korea, Republic of)

2016-11-15

Highlights: • Thermo-hydrodynamic properties of water–Al{sub 2}O{sub 3} nanofluid at PWR condition is analyzed. • Details of CFD simulation and validation procedure is outlined. • Augmented heat transfer capacity of nanofluid is governed by larger pumping power. • A new correlation for nanofluid Nusselt number in subchannel geometry is proposed. - Abstract: The computational fluid dynamic (CFD) simulation is performed to determine on the thermo- and hydrodynamic performance of the water–alumina (Al{sub 2}O{sub 3}) nanofluid in a square array subchannel featuring pitch-to-diameter ratios of 1.25 and 1.35. Two fundamental aspects of thermal hydraulics, viz. heat transfer and pressure drop, are assessed under typical pressurized water reactor (PWR) conditions at various flow rates (3 × 10{sup 5} ⩽ Re ⩽ 6 × 10{sup 5}) using pure water and differing concentrations of water–alumina nanofluid (0.5–3.0 vol.%) as coolant. Numerical results are compared against predictions made by conventional single-phase convective heat transfer and pressure loss correlations for fully developed turbulent flow. It is observed that addition of tiny nanoparticles in PWR coolant can give rise to the convective heat transfer coefficient at the expense of larger pressure drop. Nevertheless, a modified correlation as a function of nanoparticle volume fraction is proposed to estimate nanofluid Nusselt number more precisely in square array subchannel.

A new correlation for convective heat transfer coefficient of water–alumina nanofluid in a square array subchannel under PWR condition

International Nuclear Information System (INIS)

Shamim, Jubair A.; Bhowmik, Palash K.; Xiangyi, Chen; Suh, Kune Y.

2016-01-01

Highlights: • Thermo-hydrodynamic properties of water–Al_2O_3 nanofluid at PWR condition is analyzed. • Details of CFD simulation and validation procedure is outlined. • Augmented heat transfer capacity of nanofluid is governed by larger pumping power. • A new correlation for nanofluid Nusselt number in subchannel geometry is proposed. - Abstract: The computational fluid dynamic (CFD) simulation is performed to determine on the thermo- and hydrodynamic performance of the water–alumina (Al_2O_3) nanofluid in a square array subchannel featuring pitch-to-diameter ratios of 1.25 and 1.35. Two fundamental aspects of thermal hydraulics, viz. heat transfer and pressure drop, are assessed under typical pressurized water reactor (PWR) conditions at various flow rates (3 × 10"5 ⩽ Re ⩽ 6 × 10"5) using pure water and differing concentrations of water–alumina nanofluid (0.5–3.0 vol.%) as coolant. Numerical results are compared against predictions made by conventional single-phase convective heat transfer and pressure loss correlations for fully developed turbulent flow. It is observed that addition of tiny nanoparticles in PWR coolant can give rise to the convective heat transfer coefficient at the expense of larger pressure drop. Nevertheless, a modified correlation as a function of nanoparticle volume fraction is proposed to estimate nanofluid Nusselt number more precisely in square array subchannel.

The effects of drying conditions on moisture transfer and quality of pomegranate fruit leather (pestil

Directory of Open Access Journals (Sweden)

Fatih Mehmet Yılmaz

2017-01-01

Full Text Available Vacuum, cabinet and open air drying of pomegranate fruit leather were carried out at various drying conditions to monitor the drying kinetics together with bionutrient degradation of the product. Drying curves exhibited first order drying kinetics and effective moisture diffusivity values varied between 3.1 × 10−9 and 52.6 × 10−9 m2/s. The temperature dependence of the effective moisture diffusivity was satisfactorily described by an Arrhenius-type relationship. Drying conditions, product thickness and operation temperature had various effects on drying rate and final quality of the product. In terms of drying kinetics and final quality of product, vacuum drying had higher drying rate with higher conservation of phenolic, anthocyanin and ascorbic acid that is connected to faster drying condition and oxygen deficient medium. Anthocyanin content was significantly affected by drying method, drying temperature and product thickness. Scatter plot using principle component analysis enabled better understanding of moisture transfer rate and anthocyanin change under various drying conditions.

Adaptive Control for Linear Uncertain Systems with Unmodeled Dynamics Revisited via Optimal Control Modification

Science.gov (United States)

Nguyen, Nhan

2013-01-01

This paper presents the optimal control modification for linear uncertain plants. The Lyapunov analysis shows that the modification parameter has a limiting value depending on the nature of the uncertainty. The optimal control modification exhibits a linear asymptotic property that enables it to be analyzed in a linear time invariant framework for linear uncertain plants. The linear asymptotic property shows that the closed-loop plants in the limit possess a scaled input-output mapping. Using this property, we can derive an analytical closed-loop transfer function in the limit as the adaptive gain tends to infinity. The paper revisits the Rohrs counterexample problem that illustrates the nature of non-robustness of model-reference adaptive control in the presence of unmodeled dynamics. An analytical approach is developed to compute exactly the modification parameter for the optimal control modification that stabilizes the plant in the Rohrs counterexample. The linear asymptotic property is also used to address output feedback adaptive control for non-minimum phase plants with a relative degree 1.

Lack of glyphosate resistance gene transfer from Roundup Ready soybean to Bradyrhizobium japonicum under field and laboratory conditions.

Science.gov (United States)

Isaza, Laura Arango; Opelt, Katja; Wagner, Tobias; Mattes, Elke; Bieber, Evi; Hatley, Elwood O; Roth, Greg; Sanjuán, Juan; Fischer, Hans-Martin; Sandermann, Heinrich; Hartmann, Anton; Ernst, Dieter

2011-01-01

A field study was conducted at the Russell E. Larson Agricultural Research Center to determine the effect of transgenic glyphosate-resistant soybean in combination with herbicide (Roundup) application on its endosymbiont Bradyrhizobium japonicum. DNA of bacteroids from isolated nodules was analysed for the presence of the transgenic 5-enolpyruvylshikimate-3-phosphate synthase (CP4-EPSPS) DNA sequence using polymerase chain reaction (PCR). To further assess the likelihood that the EPSPS gene may be transferred from the Roundup Ready (RR) soybean to B. japonicum, we have examined the natural transformation efficiency of B. japonicum strain 110spc4. Analyses of nodules showed the presence of the transgenic EPSPS DNA sequence. In bacteroids that were isolated from nodules of transgenic soybean plants and then cultivated in the presence of glyphosate this sequence could not be detected. This indicates that no stable horizontal gene transfer (HGT) of the EPSPS gene had occurred under field conditions. Under laboratory conditions, no natural transformation was detected in B. japonicum strain 110spc4 in the presence of various amounts of recombinant plasmid DNA. Our results indicate that no natural competence state exists in B. japonicum 110spc4. Results from field and laboratory studies indicate the lack of functional transfer of the CP4-EPSPS gene from glyphosate-tolerant soybean treated with glyphosate to root-associated B. japonicum.

Adaptive Reactive Power Control of PV Power Plants for Improved Power Transfer Capability under Ultra-Weak Grid Conditions

DEFF Research Database (Denmark)

Yang, Dongsheng; Wang, Xiongfei; Liu, Fangcheng

2018-01-01

with the unity power factor. Then, considering the reactive power compensation from PV inverters, the minimum SCR in respect to Power Factor (PF) is derived, and the optimized coordination of the active and reactive power is exploited. It is revealed that the power transfer capability of PV power plant under...... of a 200 MW PV power plant demonstrate that the proposed method can ensure the rated power transfer of PV power plant with the SCR of 1.25, provided that the PV inverters are operated with the minimal PF=0.9.......This paper analyzes the power transfer limitation of the PV power plant under the ultra-weak grid condition, i.e., when the Short-Circuit Ratio (SCR) is close to 1. It explicitly identifies that a minimum SCR of 2 is required for the PV power plant to deliver the rated active power when operating...

Effects of packaging and heat transfer kinetics on drug-product stability during storage under uncontrolled temperature conditions.

Science.gov (United States)

Nakamura, Toru; Yamaji, Takayuki; Takayama, Kozo

2013-05-01

To predict the stability of pharmaceutical preparations under uncontrolled temperature conditions accurately, a method to compute the average reaction rate constant taking into account the heat transfer from the atmosphere to the product was developed. The average reaction rate constants computed with taken into consideration heat transfer (κ(re) ) were then compared with those computed without taking heat transfer into consideration (κ(in) ). The apparent thermal diffusivity (κ(a) ) exerted some influence on the average reaction rate constant ratio (R, R = κ(re) /κ(in) ). In the regions where the κ(a) was large (above 1 h(-1) ) or very small, the value of R was close to 1. On the contrary, in the middle region (0.001-1 h(-1) ), the value of R was less than 1.The κ(a) of the central part of a large-size container and that of the central part of a paper case of 10 bottles of liquid medicine (100 mL) fell within this middle region. On the basis of the above-mentioned considerations, heat transfer may need to be taken into consideration to enable a more accurate prediction of the stability of actual pharmaceutical preparations under nonisothermal atmospheres. Copyright © 2013 Wiley Periodicals, Inc.

Surface Modifications in Adhesion and Wetting

Science.gov (United States)

Longley, Jonathan

Advances in surface modification are changing the world. Changing surface properties of bulk materials with nanometer scale coatings enables inventions ranging from the familiar non-stick frying pan to advanced composite aircraft. Nanometer or monolayer coatings used to modify a surface affect the macro-scale properties of a system; for example, composite adhesive joints between the fuselage and internal frame of Boeing's 787 Dreamliner play a vital role in the structural stability of the aircraft. This dissertation focuses on a collection of surface modification techniques that are used in the areas of adhesion and wetting. Adhesive joints are rapidly replacing the familiar bolt and rivet assemblies used by the aerospace and automotive industries. This transition is fueled by the incorporation of composite materials into aircraft and high performance road vehicles. Adhesive joints have several advantages over the traditional rivet, including, significant weight reduction and efficient stress transfer between bonded materials. As fuel costs continue to rise, the weight reduction is accelerating this transition. Traditional surface pretreatments designed to improve the adhesion of polymeric materials to metallic surfaces are extremely toxic. Replacement adhesive technologies must be compatible with the environment without sacrificing adhesive performance. Silane-coupling agents have emerged as ideal surface modifications for improving composite joint strength. As these coatings are generally applied as very thin layers (coatings using the buckling instability formed between two materials of a large elastic mismatch. The elastic modulus is found to effectively predict the joint strength of an epoxy/aluminum joint that has been reinforced with silane coupling agents. This buckling technique is extended to investigate the effects of chemical composition on the elastic modulus. Finally, the effect of macro-scale roughness on silane-reinforced joints is investigated

Learning Together: How Families Responded to Education Incentives in New York City's Conditional Cash Transfer Program. Executive Summary

Science.gov (United States)

Greenberg, David; Dechausay, Nadine; Fraker, Carolyn

2011-01-01

In 2007, New York City's Center for Economic Opportunity launched Opportunity NYC-Family Rewards, an experimental, privately funded, conditional cash transfer (CCT) program to help families break the cycle of poverty. Family Rewards provided payments to low-income families in six of the city's poorest communities for achieving specific goals…

Model validation of GAMMA code with heat transfer experiment for KO TBM in ITER

International Nuclear Information System (INIS)

Yum, Soo Been; Lee, Eo Hwak; Lee, Dong Won; Park, Goon Cherl

2013-01-01

Highlights: ► In this study, helium supplying system was constructed. ► Preparation for heat transfer experiment in KO TBM condition using helium supplying system was progressed. ► To get more applicable results, test matrix was made to cover the condition for KO TBM. ► Using CFD code; CFX 11, validation and modification for system code GAMMA was performed. -- Abstract: By considering the requirements for a DEMO-relevant blanket concept, Korea (KO) has proposed a He cooled molten lithium (HCML) test blanket module (TBM) for testing in ITER. A performance analysis for the thermal–hydraulics and a safety analysis for the KO TBM have been carried out using a commercial CFD code, ANSYS-CFX, and a system code, GAMMA (GAs multicomponent mixture analysis), which was developed by the gas cooled reactor in Korea. To verify the codes, a preliminary study was performed by Lee using a single TBM first wall (FW) mock-up made from the same material as the KO TBM, ferritic martensitic steel, using a 6 MPa nitrogen gas loop. The test was performed at pressures of 1.1, 1.9 and 2.9 MPa, and under various ranges of flow rate from 0.0105 to 0.0407 kg/s with a constant wall temperature condition. In the present study, a thermal–hydraulic test was performed with the newly constructed helium supplying system, in which the design pressure and temperature were 9 MPa and 500 °C, respectively. In the experiment, the same mock-up was used, and the test was performed under the conditions of 3 MPa pressure, 30 °C inlet temperature and 70 m/s helium velocity, which are almost same conditions of the KO TBM FW. One side of the mock-up was heated with a constant heat flux of 0.3–0.5 MW/m 2 using a graphite heating system, KoHLT-2 (Korea heat load test facility-2). Because the comparison result between CFX 11 and GAMMA showed a difference tendency, the modification of heat transfer correlation included in GAMMA was performed. And the modified GAMMA showed the strong parity with CFX

Visible Light-Induced Metal Free Surface Initiated Atom Transfer Radical Polymerization of Methyl Methacrylate on SBA-15

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Liang Ma

2017-02-01

Full Text Available Surface-initiated atom transfer radical polymerization (SI-ATRP is one of the most versatile techniques to modify the surface properties of materials. Recent developed metal-free SI-ATRP makes such techniques more widely applicable. Herein photo-induced metal-free SI-ATRP of methacrylates, such as methyl methacrylate, N-isopropanyl acrylamide, and N,N-dimethylaminoethyl methacrylate, on the surface of SBA-15 was reported to fabricate organic-inorganic hybrid materials. A SBA-15-based polymeric composite with an adjustable graft ratio was obtained. The structure evolution during the SI-ATRP modification of SBA-15 was monitored and verified by FT-IR, XPS, TGA, BET, and TEM. The obtained polymeric composite showed enhanced adsorption ability for the model compound toluene in aqueous conditions. This procedure provides a low-cost, readily available, and easy modification method to synthesize polymeric composites without the contamination of metal.

An attempt to target anxiety sensitivity via cognitive bias modification.

Science.gov (United States)

Clerkin, Elise M; Beard, Courtney; Fisher, Christopher R; Schofield, Casey A

2015-01-01

Our goals in the present study were to test an adaptation of a Cognitive Bias Modification program to reduce anxiety sensitivity, and to evaluate the causal relationships between interpretation bias of physiological cues, anxiety sensitivity, and anxiety and avoidance associated with interoceptive exposures. Participants with elevated anxiety sensitivity who endorsed having a panic attack or limited symptom attack were randomly assigned to either an Interpretation Modification Program (IMP; n = 33) or a Control (n = 32) condition. During interpretation modification training (via the Word Sentence Association Paradigm), participants read short sentences describing ambiguous panic-relevant physiological and cognitive symptoms and were trained to endorse benign interpretations and reject threatening interpretations associated with these cues. Compared to the Control condition, IMP training successfully increased endorsements of benign interpretations and decreased endorsements of threatening interpretations at visit 2. Although self-reported anxiety sensitivity decreased from pre-selection to visit 1 and from visit 1 to visit 2, the reduction was not larger for the experimental versus control condition. Further, participants in IMP (vs. Control) training did not experience less anxiety and avoidance associated with interoceptive exposures. In fact, there was some evidence that those in the Control condition experienced less avoidance following training. Potential explanations for the null findings, including problems with the benign panic-relevant stimuli and limitations with the control condition, are discussed.

An attempt to target anxiety sensitivity via cognitive bias modification.

Directory of Open Access Journals (Sweden)

Elise M Clerkin

Full Text Available Our goals in the present study were to test an adaptation of a Cognitive Bias Modification program to reduce anxiety sensitivity, and to evaluate the causal relationships between interpretation bias of physiological cues, anxiety sensitivity, and anxiety and avoidance associated with interoceptive exposures. Participants with elevated anxiety sensitivity who endorsed having a panic attack or limited symptom attack were randomly assigned to either an Interpretation Modification Program (IMP; n = 33 or a Control (n = 32 condition. During interpretation modification training (via the Word Sentence Association Paradigm, participants read short sentences describing ambiguous panic-relevant physiological and cognitive symptoms and were trained to endorse benign interpretations and reject threatening interpretations associated with these cues. Compared to the Control condition, IMP training successfully increased endorsements of benign interpretations and decreased endorsements of threatening interpretations at visit 2. Although self-reported anxiety sensitivity decreased from pre-selection to visit 1 and from visit 1 to visit 2, the reduction was not larger for the experimental versus control condition. Further, participants in IMP (vs. Control training did not experience less anxiety and avoidance associated with interoceptive exposures. In fact, there was some evidence that those in the Control condition experienced less avoidance following training. Potential explanations for the null findings, including problems with the benign panic-relevant stimuli and limitations with the control condition, are discussed.

DNS, LES and RANS of turbulent heat transfer in boundary layer with suddenly changing wall thermal conditions

International Nuclear Information System (INIS)

Hattori, Hirofumi; Yamada, Shohei; Tanaka, Masahiro; Houra, Tomoya; Nagano, Yasutaka

2013-01-01

Highlights: • We study the turbulent boundary layer with heat transfer by DNS. • Turbulent boundary layers with suddenly changing wall thermal conditions are observed. • The detailed turbulent statistics and structures in turbulent thermal boundary layer are discussed. • Turbulence models in LES and RANS are evaluated using DNS results. • LES and RANS are almost in good agreement with DNS results. -- Abstract: The objectives of this study are to investigate a thermal field in a turbulent boundary layer with suddenly changing wall thermal conditions by means of direct numerical simulation (DNS), and to evaluate predictions of a turbulence model in such a thermal field, in which DNS of spatially developing boundary layers with heat transfer can be conducted using the generation of turbulent inflow data as a method. In this study, two types of wall thermal condition are investigated using DNS and predicted by large eddy simulation (LES) and Reynolds-averaged Navier–Stokes equation simulation (RANS). In the first case, the velocity boundary layer only develops in the entrance of simulation, and the flat plate is heated from the halfway point, i.e., the adiabatic wall condition is adopted in the entrance, and the entrance region of thermal field in turbulence is simulated. Then, the thermal boundary layer develops along a constant temperature wall followed by adiabatic wall. In the second case, velocity and thermal boundary layers simultaneously develop, and the wall thermal condition is changed from a constant temperature to an adiabatic wall in the downstream region. DNS results clearly show the statistics and structure of turbulent heat transfer in a constant temperature wall followed by an adiabatic wall. In the first case, the entrance region of thermal field in turbulence can be also observed. Thus, both the development and the entrance regions in thermal fields can be explored, and the effects upstream of the thermal field on the adiabatic region are

Can conditional cash transfers improve the uptake of nutrition interventions and household food security? Evidence from Odisha's Mamata scheme.

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Kalyani Raghunathan

Full Text Available There is considerable global evidence on the effectiveness of cash transfers in improving health and nutrition outcomes; however, the evidence from South Asia, particularly India, is limited. In the context of India where more than a third of children are undernourished, and where there is considerable under-utilization of health and nutrition interventions, it is opportune to investigate the impact of cash transfer programs on the use of interventions. We study one conditional cash transfer program, Mamata scheme, implemented in the state of Odisha, in India that targeted pregnant and lactating women. Using survey data on 1161 households from three districts in the state of Odisha, we examine the effect of the scheme on eight outcomes: 1 pregnancy registration; 2 receipt of antenatal services; 3 receipt of iron and folic acid (IFA tablets; 4 exposure to counseling during pregnancy; 5 exposure to postnatal counseling; 6 exclusive breastfeeding; 7 full immunization; and 8 household food security. We conduct regression analyses and correct for endogeneity using nearest-neighbor matching and inverse-probability weighting models. We find that the receipt of payments from the Mamata scheme is associated with a 5 percentage point (pp increase in the likelihood of receiving antenatal services, a 10 pp increase in the likelihood of receiving IFA tablets, and a decline of 0.84 on the Household Food Insecurity Access Scale. These results provide the first quantitative estimates of effects associated with the Mamata scheme, which can inform the design of government policies related to conditional cash transfers.

Internet-delivered attention bias modification training in individuals with social anxiety disorder - a double blind randomized controlled trial

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Carlbring Per

2012-06-01

Full Text Available Abstract Background Computerized cognitive bias modification for social anxiety disorder has in several well conducted trials shown great promise with as many as 72% no longer fulfilling diagnostic criteria after a 4 week training program. To test if the same program can be transferred from a clinical setting to an internet delivered home based treatment the authors conducted a randomized, double-blind placebo-controlled trial. Methods After a diagnostic interview 79 participants were randomized to one of two attention training programs using a probe detection task. In the active condition the participant was trained to direct attention away from threat, whereas in the placebo condition the probe appeared with equal frequency in the position of the threatening and neutral faces. Results Results were analyzed on an intention-to-treat basis, including all randomized participants. Immediate and 4-month follow-up results revealed a significant time effect on all measured dimensions (social anxiety scales, general anxiety and depression levels, quality of life. However, there were no time x group interactions. The lack of differences in the two groups was also mirrored by the infinitesimal between group effect size both at post test and at 4-month follow-up. Conclusion We conclude that computerized attention bias modification may need to be altered before dissemination for the Internet. Trial registration ISRCTN01715124

Highly Efficient Catalytic Synthesis of α-Amino Acids under Phase-Transfer Conditions with a Novel Catalyst/Substrate Pair

NARCIS (Netherlands)

Belokon, Yuri N.; Kochetkov, Konstantin A.; Churkina, Tatiana D.; Ikonnikov, Nikolai S.; Larionov, Oleg V.; Harutyunyan, Syuzanna R.; Vyskočil, Štepán; North, Michael; Kagan, Henri B.

2001-01-01

A facile and fast enantioselective synthesis of α-amino acids with high ee values was achieved by the asymmetric alkylation of the glycine derivative under phase-transfer conditions with (R)- or (S)-2-amino-2'-hydroxy-1,1'-binaphthyl (NOBIN). The ee value of the catalyst can be as little as 40 %

Immuno-Northern Blotting: Detection of RNA Modifications by Using Antibodies against Modified Nucleosides.

Directory of Open Access Journals (Sweden)

Eikan Mishima

Full Text Available The biological roles of RNA modifications are still largely not understood. Thus, developing a method for detecting RNA modifications is important for further clarification. We developed a method for detecting RNA modifications called immuno-northern blotting (INB analysis and herein introduce its various capabilities. This method involves the separation of RNAs using either polyacrylamide or agarose gel electrophoresis, followed by transfer onto a nylon membrane and subsequent immunoblotting using antibodies against modified nucleosides for the detection of specific modifications. We confirmed that INB with the antibodies for 1-methyladenosine (m1A, N6-methyladenosine (m6A, pseudouridine, and 5-methylcytidine (m5C showed different modifications in a variety of RNAs from various species and organelles. INB with the anti-m5C antibody revealed that the antibody cross-reacted with another modification on DNA, suggesting the application of this method for characterization of the antibody for modified nucleosides. Additionally, using INB with the antibody for m1A, which is a highly specific modification in eukaryotic tRNA, we detected tRNA-derived fragments known as tiRNAs under the cellular stress response, suggesting the application for tracking target RNA containing specific modifications. INB with the anti-m6A antibody confirmed the demethylation of m6A by the specific demethylases fat mass and obesity-associated protein (FTO and ALKBH5, suggesting its application for quantifying target modifications in separated RNAs. Furthermore, INB demonstrated that the knockdown of FTO and ALKBH5 increased the m6A modification in small RNAs as well as in mRNA. The INB method has high specificity, sensitivity, and quantitative capability, and it can be employed with conventional experimental apparatus. Therefore, this method would be useful for research on RNA modifications and metabolism.

Immuno-Northern Blotting: Detection of RNA Modifications by Using Antibodies against Modified Nucleosides.

Science.gov (United States)

Mishima, Eikan; Jinno, Daisuke; Akiyama, Yasutoshi; Itoh, Kunihiko; Nankumo, Shinnosuke; Shima, Hisato; Kikuchi, Koichi; Takeuchi, Yoichi; Elkordy, Alaa; Suzuki, Takehiro; Niizuma, Kuniyasu; Ito, Sadayoshi; Tomioka, Yoshihisa; Abe, Takaaki

2015-01-01

The biological roles of RNA modifications are still largely not understood. Thus, developing a method for detecting RNA modifications is important for further clarification. We developed a method for detecting RNA modifications called immuno-northern blotting (INB) analysis and herein introduce its various capabilities. This method involves the separation of RNAs using either polyacrylamide or agarose gel electrophoresis, followed by transfer onto a nylon membrane and subsequent immunoblotting using antibodies against modified nucleosides for the detection of specific modifications. We confirmed that INB with the antibodies for 1-methyladenosine (m1A), N6-methyladenosine (m6A), pseudouridine, and 5-methylcytidine (m5C) showed different modifications in a variety of RNAs from various species and organelles. INB with the anti-m5C antibody revealed that the antibody cross-reacted with another modification on DNA, suggesting the application of this method for characterization of the antibody for modified nucleosides. Additionally, using INB with the antibody for m1A, which is a highly specific modification in eukaryotic tRNA, we detected tRNA-derived fragments known as tiRNAs under the cellular stress response, suggesting the application for tracking target RNA containing specific modifications. INB with the anti-m6A antibody confirmed the demethylation of m6A by the specific demethylases fat mass and obesity-associated protein (FTO) and ALKBH5, suggesting its application for quantifying target modifications in separated RNAs. Furthermore, INB demonstrated that the knockdown of FTO and ALKBH5 increased the m6A modification in small RNAs as well as in mRNA. The INB method has high specificity, sensitivity, and quantitative capability, and it can be employed with conventional experimental apparatus. Therefore, this method would be useful for research on RNA modifications and metabolism.

Accuracy Improvement of Discharge Measurement with Modification of Distance Made Good Heading

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Jongkook Lee

2016-01-01

Full Text Available Remote control boats equipped with an Acoustic Doppler Current Profiler (ADCP are widely accepted and have been welcomed by many hydrologists for water discharge, velocity profile, and bathymetry measurements. The advantages of this technique include high productivity, fast measurements, operator safety, and high accuracy. However, there are concerns about controlling and operating a remote boat to achieve measurement goals, especially during extreme events such as floods. When performing river discharge measurements, the main error source stems from the boat path. Due to the rapid flow in a flood condition, the boat path is not regular and this can cause errors in discharge measurements. Therefore, improvement of discharge measurements requires modification of boat path. As a result, the measurement errors in flood flow conditions are 12.3–21.8% before the modification of boat path, but 1.2–3.7% after the DMG modification of boat path. And it is considered that the modified discharges are very close to the observed discharge in the flood flow conditions. In this study, through the distance made good (DMG modification of the boat path, a comprehensive discharge measurement with high accuracy can be achieved.

Temperature condition in decreasing heat transfer zone for NPP steam generators

International Nuclear Information System (INIS)

Kudryavtsev, I.S.; Paskar', B.L.; Sudakov, A.V.

1985-01-01

An experimental set-up is described and the results of temperature pulsation investigation are presented for coil steam generating channel surfaces of the NPP helium and sodium cooled HTGR. The investigations are carried out at the heat flux density of 350-900 kW/m 3 , the mass rate of 350-2000 kg/(m 2 Xs), the pressUre of 15 MPa. Temperature pulsations occur due to instability of heat transfer in the near-wall region. The results show that the critical region of burnout has a local character. Pulsation dependences on operating conditions are given. The required resource for the steam generating channel may be provided by chosing the ratio of heat flux to the mass rate, the ratio being equal to 0.5 kJ/kg for the channel with the internal diameter of 19 mm, made of the 12Kh2M steel, the wall thickness of 3 mm. In this case the maximum span of temperature pulsations doesn't exceed 25-30 K

Effect of tooth profile modification on wear in internal gears

Science.gov (United States)

Tunalioglu, M. S.; Tuc, B.

2018-05-01

Internal gears are often used in the automotive industry when two gears are required to rotate in the same direction. Tooth shapes, slippage speeds at the beginning and end of meshing are different according to the external gears. Manufacturing of internal gears is more difficult than external gears. Thus, it is necessary to determine the working conditions and wear behavior of internal gears carefully. The profile modification method in terms of strength and surface tension of the gear mechanism are performed in order to increase the load-carrying capability. In this study, profile modification method was performed in the internal gears to reduce the wear on the teeth. For this purpose, the wear of the internal gears was theoretically investigated by adapting the Archard wear equation to the internal gears. Closed circuit power circulation system was designed and manufactured to experimentally investigate the wear in internal gears. With this system, wear tests of gears made of St 50 material without profile modification and different profile modifications were made and the results were compared. Experimental study was performed in the same loading and cycle time conditions to validate the theoretical results and it was seen that the results are compatible. According to the experimental results, it is seen that in the internal gears, when profile modification done the wear is decreased in the teeth tip region.

Cloning Endangered Felids by Interspecies Somatic Cell Nuclear Transfer.

Science.gov (United States)

Gómez, Martha C; Pope, C Earle

2015-01-01

In 2003, the first wild felid was produced by interspecies somatic cell nuclear transfer. Since then other wild felid clone offspring have been produced by using the same technique with minor modifications. This chapter describes detailed protocols used in our laboratory for (1) the isolation, culture, and preparation of fibroblast cells as donor nucleus, and (2) embryo reconstruction with domestic cat enucleated oocytes to produce cloned embryos that develop to the blastocyst stage in vitro and, after transfer into synchronized recipients, establish successful pregnancies.

Monovalent cations transfer through isolated human amnion: a new pharmacological model

Energy Technology Data Exchange (ETDEWEB)

Bara, M.; Guiet-Bara, A.; Durlach, J.

1985-04-01

Transfer of monovalent cations through the isolated human amnion consists of different factors: paracellular, coupling, ATPase dependent cellular transfer, leak cellular transfer. Understanding this transfer permits testing of the action of various substances. Physiological substances (Mg, taurine) increase ionic transfer and there is a vicarious effect between Mg and taurine. The tocolytic agents MgSO/sub 4/ and ethanol do not exhibit a good effect on the transfer: decrease with ethanol; equality between entry and exit fluxes with MgSO/sub 4/. On the other hand, amphotericin B increases mother-to-fetus transfer. Polluting metals (Pb, Cd, Hg, As) dramatically reduce exchanges and almost completely inhibit amnion permeability. Ingestion of ethanol also exhibits a dramatic effect on the exchange between mother and fetus through the amnion. Study of ionic transfer in vitro can be considered a pharmacological model to investigate the modifications of mother-fetus exchanges by various substances.

Multidimensional Quantum Mechanical Modeling of Electron Transfer and Electronic Coherence in Plant Cryptochromes: The Role of Initial Bath Conditions.

Science.gov (United States)

Mendive-Tapia, David; Mangaud, Etienne; Firmino, Thiago; de la Lande, Aurélien; Desouter-Lecomte, Michèle; Meyer, Hans-Dieter; Gatti, Fabien

2018-01-11

A multidimensional quantum mechanical protocol is used to describe the photoinduced electron transfer and electronic coherence in plant cryptochromes without any semiempirical, e.g., experimentally obtained, parameters. Starting from a two-level spin-boson Hamiltonian we look at the effect that the initial photoinduced nuclear bath distribution has on an intermediate step of this biological electron transfer cascade for two idealized cases. The first assumes a slow equilibration of the nuclear bath with respect to the previous electron transfer step that leads to an ultrafast decay with little temperature dependence; while the second assumes a prior fast bath equilibration on the donor potential energy surface leading to a much slower decay, which contrarily displays a high temperature dependence and a better agreement with previous theoretical and experimental results. Beyond Marcus and semiclassical pictures these results unravel the strong impact that the presence or not of equilibrium initial conditions has on the electronic population and coherence dynamics at the quantum dynamics level in this and conceivably in other biological electron transfer cascades.

Effect of conditional cash transfer on choice and utilization of contraceptives among newly married couples in Satara district

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Asha K Pratinidhi

2014-01-01

Full Text Available Context: Satara district of western Maharashtra is in late expanding phase of demographic cycle. Postponement of first pregnancy with the use of reversible contraceptives is the need of the hour. Since 2007, Satara district is implementing a conditional cash transfer scheme second honeymoon package (SHP. Objectives: The objectives of this study are: (1 To find out the effect of conditional cash transfer on choice and utilization of contraceptives among participants of SHP. (2 To identify various barriers to the use of contraceptives. Materials and Methods: This was an evaluation study of a community based interventional program. Cases were the participants of SHP program while the controls were the couples residing in the same village as that of participants and married in the same year. Enquiries were made about their knowledge of contraceptives, reasons of postponement, choice of contraceptives, problems faced while using them, perceived benefits of participation, reasons for non-participation and non-use of contraceptives, etc. Results: This study has found out that 24.8% controls and 57.6% participant couples were having knowledge of contraception before their marriage. Amongst the participants of the scheme and controls, male condom was the most popular method used by 80.8% participants, followed by oral pills by 9.22% couples. Contraception prevalence rate among control couples was 17.6%, while that in participants was 91.8%. Resistance from family members, side-effects and failure of contraceptives were some of the barriers to their use. Conclusions: Conditional cash transfer has encouraged the use of contraceptives in acceptors of SHP. By participating in SHP and postponing first pregnancy 15.8% could complete their education, job/career betterment achieved by 16.4% and 19.3% adored marital pleasure.

Radiation modification of materials

International Nuclear Information System (INIS)

Pikaev, A.K.

1987-01-01

Industrial and radiation chemical processes of material modification based on cross-linking of polymers as a result of radiation are considered. Among them are production of cables and rods with irradiated modified insulation, production of hardened and thermo-shrinkaging polymer products (films, tubes, fashioned products), production of radiation cross-linked polyethylene foam, technology of radiation vulcanization of elastomers. Attention is paid to radiation plants on the basis of γ-sources and electron acceleratos as well as to radiation conditions

Influence of various aspects of low Reynolds number k-ε turbulence models on predicting in-tube buoyancy affected heat transfer to supercritical pressure fluids

International Nuclear Information System (INIS)

Zhao, Chen-Ru; Zhang, Zhen; Jiang, Pei-Xue; Bo, Han-Liang

2017-01-01

Highlights: • Understanding of the mechanism of buoyancy effect on supercritical heat transfer. • Turbulence related parameters in upward and downward flows were compared. • Turbulent Prandtl number affected the prediction insignificantly. • Buoyancy production was insignificant compared with shear production. • Damping function had the greatest effect and is a priority for further modification. - Abstract: Heat transfer to supercritical pressure fluids was modeled for normal and buoyancy affected conditions using several low Reynolds number k-ε models, including the Launder and Sharma, Myong and Kasagi, and Abe, Kondoh and Nagano, with the predictions compared with experimental data. All three turbulence models accurately predicted the cases without heat transfer deterioration, but failed to accurately predict the cases with heat transfer deterioration although the general trends were captured, indicating that further improvements and modifications are needed for the low Reynolds number k-ε turbulence models to better predict buoyancy deteriorated heat transfer. Further investigations studied the influence of various aspects of the low Reynolds number k-ε turbulence models, including the turbulent Prandtl number, the buoyancy production of turbulent kinetic energy, and the damping function to provide guidelines for model development to more precisely predict buoyancy affected heat transfer. The results show that the turbulent Prandtl number and the buoyancy production of turbulent kinetic energy have little influence on the predictions for cases in this study, while new damping functions with carefully selected control parameters are needed in the low Reynolds number k-ε turbulence models to correctly predict the buoyancy effect for heat transfer simulations in various applications such as supercritical pressure steam generators (SPSGs) in the high temperature gas cooled reactor (HTR) and the supercritical pressure water reactor (SCWR).

Influence of various aspects of low Reynolds number k-ε turbulence models on predicting in-tube buoyancy affected heat transfer to supercritical pressure fluids

Energy Technology Data Exchange (ETDEWEB)

Zhao, Chen-Ru; Zhang, Zhen [Institute of Nuclear and New Energy Technology of Tsinghua University, Advanced Nuclear Energy Technology Cooperation Innovation Centre, Key Laboratory of Advanced Nuclear Engineering and Safety, Ministry of Education, Beijing 100084 (China); Jiang, Pei-Xue, E-mail: jiangpx@tsinghua.edu.cn [Beijing Key Laboratory of CO_2 Utilization and Reduction Technology/Key Laboratory for Thermal Science and Power Engineering of Ministry of Education, Department of Thermal Engineering, Tsinghua University, Beijing 100084 (China); Bo, Han-Liang [Institute of Nuclear and New Energy Technology of Tsinghua University, Advanced Nuclear Energy Technology Cooperation Innovation Centre, Key Laboratory of Advanced Nuclear Engineering and Safety, Ministry of Education, Beijing 100084 (China)

2017-03-15

Highlights: • Understanding of the mechanism of buoyancy effect on supercritical heat transfer. • Turbulence related parameters in upward and downward flows were compared. • Turbulent Prandtl number affected the prediction insignificantly. • Buoyancy production was insignificant compared with shear production. • Damping function had the greatest effect and is a priority for further modification. - Abstract: Heat transfer to supercritical pressure fluids was modeled for normal and buoyancy affected conditions using several low Reynolds number k-ε models, including the Launder and Sharma, Myong and Kasagi, and Abe, Kondoh and Nagano, with the predictions compared with experimental data. All three turbulence models accurately predicted the cases without heat transfer deterioration, but failed to accurately predict the cases with heat transfer deterioration although the general trends were captured, indicating that further improvements and modifications are needed for the low Reynolds number k-ε turbulence models to better predict buoyancy deteriorated heat transfer. Further investigations studied the influence of various aspects of the low Reynolds number k-ε turbulence models, including the turbulent Prandtl number, the buoyancy production of turbulent kinetic energy, and the damping function to provide guidelines for model development to more precisely predict buoyancy affected heat transfer. The results show that the turbulent Prandtl number and the buoyancy production of turbulent kinetic energy have little influence on the predictions for cases in this study, while new damping functions with carefully selected control parameters are needed in the low Reynolds number k-ε turbulence models to correctly predict the buoyancy effect for heat transfer simulations in various applications such as supercritical pressure steam generators (SPSGs) in the high temperature gas cooled reactor (HTR) and the supercritical pressure water reactor (SCWR).

[Testing of the effect of classic conditioning stimuli in human experiment by means of the transfer of control paradigm].

Science.gov (United States)

Wolter, J

1999-01-01

Pavlovian conditioning in animals is often evaluated by means of transfer of control experiments. With human subjects, however, only very few studies have been conducted and the outcomes were often not in accordance with theoretical explanations based on studies with animals. A theoretical framework is presented that tries to integrate the results of the human conditioning paradigm and the animal conditioning paradigm as well, with reference to the well-known Yerkes-Dodson law. The experimental study with human subjects (N = 24) confirmed the predictions out of this framework, when a procedure similar to animal research is applied.

Basic heat transfer

CERN Document Server

Bacon, D H

2013-01-01

Basic Heat Transfer aims to help readers use a computer to solve heat transfer problems and to promote greater understanding by changing data values and observing the effects, which are necessary in design and optimization calculations.The book is concerned with applications including insulation and heating in buildings and pipes, temperature distributions in solids for steady state and transient conditions, the determination of surface heat transfer coefficients for convection in various situations, radiation heat transfer in grey body problems, the use of finned surfaces, and simple heat exc

Phospholipid transfer from vesicles to high density lipoproteins, catalyzed by human plasma phospholipid transfer protein

International Nuclear Information System (INIS)

Sweeny, S.A.

1985-01-01

Human plasma phospholipid transfer protein (PLTP) catalyzes the mass transfer of phosphatidylcholine (PC). Partial purification of PLTP yielded proteins with apparent M/sub r/ = 59,000 and 40,000 by SDS-PAGE. PLTP activity was measured by transfer of [ 14 C]L-α-dipalmitoyl PC from egg-PC vesicles to HDL. Activity was enhanced at low pH (4.5) upon addition of β-mercaptoethanol while Ca +2 and Na + had no effect. E/sub act/ for facilitated PC transfer was 18.2 +/- 2 kcal/mol. The donor specificity of PLTP was examined using vesicles containing egg-PC plus cholesterol or sphingomyelin. The fluidity of the donor membrane (measured by fluorescence polarization of diphenylhexatriene) correlated strongly with a decrease in PLTP activity. Phosphatidic acid did not affect activity. Increase in vesicle size reduced activity. The acceptor specificity of PLTP was examined using chemically modified HDL. PLTP activity increased up to 1.7-fold with an initial increase in negative charge and then decreased upon extensive modification. A mechanism is proposed where PLTP binds to vesicls and enhances the diffusion of PC into the medium where it is adsorbed by HDL

Conditional Monte Carlo sampling to find branching architectures of polymers from radical polymerizations with transfer to polymer and recombination termination

NARCIS (Netherlands)

Iedema, P.D.; Wulkow, M.; Hoefsloot, H.C.J.

2007-01-01

A model is developed that predicts branching architectures of polymers from radical polymerization with transfer to polymer and termination by disproportionation and recombination, in a continuously stirred tank reactor (CSTR). It is a so-called conditional Monte Carlo (MC) method generating

Heat transfer in an evaporation-condensation system in simulated weightlessness conditions

Science.gov (United States)

Bologa, M. K.; Grosu, F. P.; Kozhevnikov, I. V.; Motorin, O. V.; Polikarpov, A. A.

2017-10-01

The process of heat transfer in an evaporation-condensation system (ECS) at circulation of dielectric liquid in a closed thermoelectrohydrodynamic (TEHD) loop consisting of an evaporator, a condenser and electrohydrodynamic (EHD) pump for pumping of heat carrier, is considered. Previously, the authors studied the dependence of heat transfer on the angle of rotation of TEHD loop in a vertical plane. The report contains the results of studies of heat transfer at electrohydrodynamic pumping of the heat carrier (8% solution of acetone in Freon 113) in the condenser area by means of EHD pump of “cone-cone” type. All elements of the ECS are arranged in a horizontal plane and the heat transfer from the heater to the condenser without EHD pumping is impossible. A pulsating heat carrier flow mode, depending on the heat input and the voltage applied to the pump, takes place at EHD pumping. As the input power is decreasing the frequency of the coolant pulsations as well as the departure diameter and number of vapour bubbles are also decreasing. At some critical heat input the pulsations disappear and the transition from turbulent mode to the laminar one takes place causing the decrease of the heat transfer coefficient. The increase of the pumping flow rate by raising the voltage applied to the EHD pump, results in a partial suppression of boiling. The maximum intensification of heat transfer is reached at pulsation frequency of 1.25 Hz. The maximum heat flow from the heater was 4.2·104 W/m2. Graphical representation and the physical interpretation of the results, which reflect the essence of the process, are given.

Controlled Environment Specimen Transfer

DEFF Research Database (Denmark)

Damsgaard, Christian Danvad; Zandbergen, Henny W.; Hansen, Thomas Willum

2014-01-01

an environmental transmission electron microscope to an in situ X-ray diffractometer through a dedicated transmission electron microscope specimen transfer holder, capable of sealing the specimen in a gaseous environment at elevated temperatures. Two catalyst material systems have been investigated; Cu/ZnO/Al2O3...... transferred in a reactive environment to the environmental transmission electron microscope where further analysis on the local scale were conducted. The Co/Al2O3 catalyst was reduced in the environmental microscope and successfully kept reduced outside the microscope in a reactive environment. The in situ......Specimen transfer under controlled environment conditions, such as temperature, pressure, and gas composition, is necessary to conduct successive complementary in situ characterization of materials sensitive to ambient conditions. The in situ transfer concept is introduced by linking...

A Kantian argument against comparatively advantageous genetic modification.

Science.gov (United States)

Jensen, David

2011-08-01

The genetic modification of children is becoming a more likely possibility given our rapid progress in medical technologies. I argue, from a broadly Kantian point of view, that at least one kind of such modification-modification by a parent for the sake of a child's comparative advantage-is not rationally justified. To argue this, I first characterize a necessary condition on reasons and rational justification: what is a reason for an agent to do an action in one set of circumstances must be a reason for any in those circumstances to do the action. I then show that comparatively advantageous genetic modification violates this principle since a child's "getting ahead" through genetic modification cannot be rationally justified unless other children also could receive the modification, thus rendering the advantage useless. Finally, I consider the major objection to this it seems to disallow all cases of a parent's helping a child get ahead, something that parents normally engage in with their children. I argue that typical practices of developing a comparative advantage in a child, as well as practices of societal competition in general, do not conflict because they involve circumstances that mitigate the universal character of reasons. Many ordinary cases of competitive advantage that we think of as unjust, in fact, can be explained by my argument.

Do multiple body modifications alter pain threshold?

Science.gov (United States)

Yamamotová, A; Hrabák, P; Hříbek, P; Rokyta, R

2017-12-30

In recent years, epidemiological data has shown an increasing number of young people who deliberately self-injure. There have also been parallel increases in the number of people with tattoos and those who voluntarily undergo painful procedures associated with piercing, scarification, and tattooing. People with self-injury behaviors often say that they do not feel the pain. However, there is no information regarding pain perception in those that visit tattoo parlors and piercing studios compared to those who don't. The aim of this study was to compare nociceptive sensitivity in four groups of subjects (n=105, mean age 26 years, 48 women and 57 men) with different motivations to experience pain (i.e., with and without multiple body modifications) in two different situations; (1) in controlled, emotionally neutral conditions, and (2) at a "Hell Party" (HP), an event organized by a piercing and tattoo parlor, with a main event featuring a public demonstration of painful techniques (burn scars, hanging on hooks, etc.). Pain thresholds of the fingers of the hand were measured using a thermal stimulator and mechanical algometer. In HP participants, information about alcohol intake, self-harming behavior, and psychiatric history were used in the analysis as intervening variables. Individuals with body modifications as well as without body modifications had higher thermal pain thresholds at Hell Party, compared to thresholds measured at control neutral conditions. No such differences were found relative to mechanical pain thresholds. Increased pain threshold in all HP participants, irrespectively of body modification, cannot be simply explained by a decrease in the sensory component of pain; instead, we found that the environment significantly influenced the cognitive and affective component of pain.

Modification of surfaces and surface layers by non equilibrium processes

International Nuclear Information System (INIS)

Beamson, G.; Brennan, W.J.; Clark, D.T.; Howard, J.

1988-01-01

Plasmas are examples of non-equilibrium phenomena which are being used increasingly for the synthesis and modification of materials impossible by conventional routes. This paper introduces methods available by describing the construction and characteristics of some equipment used for the production of different types of plasmas and other non-equilibrium phenomena. This includes high energy ion beams. The special features, advantages and disadvantages of the techniques will be described. There are a multitude of potential application relevant to electronic, metallic, ceramic, and polymeric materials. However, scale-up from the laboratory to production equipment depends on establishing a better understanding of both the physics and chemistry of plasma as well as plasma-solid interactions. Examples are given of how such an understanding can be gained. The chemical analysis of polymer surfaces undergoing modification by inert gas, hydrogen or oxygen plasmas is shown to give physical information regarding the relative roles of diffusion of active species, and direct and radiative energy transfer from the plasma. Surface modification by plasma depositing a new material onto an existing substrate is discussed with particular reference to the deposition of amorphous carbon films. Applications of the unique properties of these films are outlined together with our current understanding of these properties based on chemical and physical methods of analysis of both the films and the plasmas producing them. Finally, surface modification by ion beams is briefly illustrated using examples from the electronics and metals industries where the modification has had a largely physical rather than chemical effect on the starting material. (orig.)

Assessing the representativeness of durability tests for wood pellets by DEM Simulation - Comparing conditions in a durability test with transfer chutes

Science.gov (United States)

Mahajan, Aditya; Dafnomilis, Ioannis; Hancock, Victoria; Lodewijks, Gabriel; Schott, Dingena

2017-06-01

Dust generation when handling wood pellets is related to the durability of the product, in other words the wear rate of particles subject to forces. During transport, storage and handling wood pellets undergo different forces when interacting with different pieces of equipment. This paper assesses the representativeness of the tumbling can test in relation to transfer chutes, by comparing forces acting on wood pellets in durability tests and in transfer chutes using DEM. The study also incorporates effects such as shape and size variations. The results showed that the tumbling can test underestimates compressive and tangential forces. Since the tested material is subject to milder conditions than in reality, it can be concluded that this test is not representative for the conditions in the supply chain of wood pellets.

The Au-S bond in biomolecular adsorption and electrochemical electron transfer

DEFF Research Database (Denmark)

Ford, M. J.; Hush, N. S.; Marcuccio, S.

Interfacial electrochemical electron transfer (ET) of redox metalloproteins is long established. For the proteins to retain full ET or enzyme activity, modification of the electrode surfaces, such as goldsurfaces by self-assembled molecular monolayers (SAMs), is nearly always required, where pure...

Coupled radiative transfer equation and diffusion approximation model for photon migration in turbid medium with low-scattering and non-scattering regions

International Nuclear Information System (INIS)

Tarvainen, Tanja; Vauhkonen, Marko; Kolehmainen, Ville; Arridge, Simon R; Kaipio, Jari P

2005-01-01

In this paper, a coupled radiative transfer equation and diffusion approximation model is extended for light propagation in turbid medium with low-scattering and non-scattering regions. The light propagation is modelled with the radiative transfer equation in sub-domains in which the assumptions of the diffusion approximation are not valid. The diffusion approximation is used elsewhere in the domain. The two equations are coupled through their boundary conditions and they are solved simultaneously using the finite element method. The streamline diffusion modification is used to avoid the ray-effect problem in the finite element solution of the radiative transfer equation. The proposed method is tested with simulations. The results of the coupled model are compared with the finite element solutions of the radiative transfer equation and the diffusion approximation and with results of Monte Carlo simulation. The results show that the coupled model can be used to describe photon migration in turbid medium with low-scattering and non-scattering regions more accurately than the conventional diffusion model

The transfer of radionuclides in the terrestrial environments. Recent research results in monsoon tropical condition of Vietnam

International Nuclear Information System (INIS)

Binh, Nguyen Thanh; Y, Truong; Sieu, Le Nhu; Ngo, Nguyen Trong; Phuc, Nguyen Van; Huong, Mai Thi; Quang, Nguyen Hao; Nhan, Dang Duc

2003-01-01

The data on Radionuclide transfer parameters in the environments, which are used in radioecological models, are very necessary for setting release limits of radioactive effluent and assessing the radiation dose to Man related to the releases of radionuclides from nuclear facilities. They strongly depend on climatic, geographic, environmental and pedological conditions. For temperate environments, they are abundant and have been established fairly well. Meanwhile the literature data are still scare and dispersal for Tropical and Sub-tropical zones. Besides, the improvement of Environmental Transfer Models and Parameters is an important problem so that they may be adapted for Southeast Asian countries including Japan as environmental conditions and foodstuffs in this Region are significantly different from those in Europe and North America. The paper presents measurements results of the dry deposition velocities of atmospheric aerosols carrying 7 Be, 137 Cs radionuclides and measurements results of soil to plant transfer factors (TF) for 60 Co, 65 Zn, 85 ASr and 134 Cs resulted from the out door radiotracer experiments with large pots. The selected soil types (Podzolic, Ferralitic, Ferralic Acrisols, Eutric Fluvisols and Orthi-thionic Fluvisols soil) and the plants (rice, black bean, cabbage, lettuce, tomato, cucumber, carrot, white radish, potato) used for the research are the most common in Vietnam. The measured Vg values (cm/s) are in the range of 0.01 - 1.84 for 7 Be and 1.95 - 49.77 for 137 Cs. An analysis of the associated meteorological parameters showed some correlations between 7 Be Vg with humidity and 137 Cs Vg with wind velocity. More than 400 TF (edible part) values were determined and their dependences on some soil parameters have been shown. (author)

The role of community sports coaches in creating optimal social conditions for life skill development and transferability - a salutogenic perspective

NARCIS (Netherlands)

Super, S.; Verkooijen, K.T.; Koelen, M.A.

2018-01-01

Sport is widely recognised as having the potential to enhance the personal development of socially vulnerable youth, yet there is very limited knowledge on how community sports coaches can create optimal social conditions for life skill development and transferability. We adopt a salutogenic

ASPECTS REGARDING THE SHARE TRANSFER

Directory of Open Access Journals (Sweden)

Cristina Cojocaru

2015-11-01

Full Text Available Throughout its content, the memorandum of association, even in the case of a limited liability company, stipulates the contribution of each shareholder to the share capital while the share capital is divided into shares, corresponding to the contribution of each shareholder to the share capital. The limited liability company is established in consideration of the people who set it up and as such, the share transfer is subject to certain conditions provided by law. Therefore, the law sets out strict conditions for share transfer in the case the transfer is done to one or more shareholders, but especially if the transfer is done to people outside the company, or following the inheritance. If the transfer is done to a shareholder, such is possible provided that this transfer has not been prohibited by the act of incorporation itself. Instead, the transfer to people outside the company cannot be done without the cons ent of shareholders representing at least three quarters of the capital. In case of share transfer by succession, the law allows it provided that this transfer is permitted within the memorandum of association .

Etikken bag kunstig selektion og genmodifikation af planter: The Ethics of Artificial Selection and Genetic Modification of Plants

OpenAIRE

Armstrong, Freya; Børgesen, Lasse Faber; Gierløff, Anders Pihl; Justesen, Louise; Niemeier, Sebastian; Sandgaard, Monica; Steensgaard, Ida Mathilde

2013-01-01

Artificial selection and genetic modification are both methods which are used to maximize crop profit. The recent years’ development in the genetic engineering sector has made it possible to transfer a specific trait from one organism to another. The development has caused a widespread ethical debate on the subject. This study examines two different cases based on genetic modification and artificial selection of plants respectively. The aim of this study is to determine, which ethics particip...

Guidance on the Implementation of Modifications to Mitigate Beyond Design Basis Accidents

Energy Technology Data Exchange (ETDEWEB)

Dermarkar, F.; Marczak, J.; O’Neill, M., E-mail: fred.dermarkar@opg.com [Ontario Power Generation, Pickering, Ontario (Canada)

2014-10-15

Following the events at Fukushima, Canadian Nuclear Power Plants (NPP) procured equipment and initiated modifications to improve response capability for Beyond Design Basis Accidents (BDBA). These changes were not typical of other design modifications to the nuclear power plants and reinforced the need for additional guidance for modifications to address BDBA. This paper describes the guidance that was developed to guide the design, procurement, installation, operation, and maintenance of equipment and modifications to mitigate BDBAs. The guidance developed prescribes a graded approach based on a categorization of the nature of the modification. Four categories of modifications are introduced, with the distinction being the degree of interface with existing design basis systems, structures and components (SSCs). This has resulted in a cost-effective means of implementing additional capability to mitigate BDBA conditions, and yet ensure the design basis capability of SSCs is maintained. (author)

Modification of the Riemann problem and the application for the boundary conditions in computational fluid dynamics

Directory of Open Access Journals (Sweden)

Kyncl Martin

2017-01-01

cases. Moreover, using such construction, the local conservation laws are not violated. Algorithms for the solution of the modified Riemann problems were coded and used within our own developed code for the solution of the compressible gas flow (the Euler, the Navier-Stokes, and the RANS equations. Numerical examples show superior behaviour of the suggested boundary conditions. Constructed boundary conditions are robust and accelerate the convergence of the method. The original result of our work is the analysis of various modifications of the Riemann problem and its applications.

Conditioned Stimuli’s Role in Relapse: Pre-Clinical Research on Pavlovian Instrumental Transfer

Science.gov (United States)

Lamb, R.J.; Schindler, W.; Pinkston, Jonathan W.

2016-01-01

Rationale and Objective Pavlovian learning is central to many theories of addiction. In these theories, stimuli paired with drug ingestion become Conditioned Stimuli (CS) and subsequently elicit drug-seeking and -taking. However in most relevant studies, Pavlovian and instrumental learning are confounded. This confound may be avoided in Pavlovian-Instrumental-Transfer (PIT) procedures. In PIT, Pavlovian and instrumental learning are established separately, and then combined. In order to better understand the role of CSs in addiction, we review the relevant studies using PIT. Findings We identified seven articles examining PIT effects of ethanol- or cocaine-paired CSs. Under at least one condition six of these articles reported CS-elicited increases in responding previously maintained by drug. However, the only study using the optimal control condition failed to find a CS-elicited increase. Two studies examining CS specificity found the CS also increased responding maintained by a different reinforcer. Two studies examined if CSs elicit increases in actual drug-taking. Both failed to find CS-elicited increases, i.e., no study shows CS-elicited increases in actual drug-taking. Further, CS-elicited increases in extinguished responding are short-lived. Conclusions These findings are not entirely consistent with Pavlovian learning playing a central role in addiction. However, design issues can explain most of these inconsistencies. Studies without these design issues are needed. Additionally, existing theories hypothesize drug-paired CSs increase drug-taking by increasing motivation, by eliciting conditioned responses that make drug-seeking more probable, or by a combination of these. Work distinguishing between these mechanisms would also be useful. PMID:26800688

Nucleate Boiling Heat Transfer Studied Under Reduced-Gravity Conditions

Science.gov (United States)

Chao, David F.; Hasan, Mohammad M.

2000-01-01

Boiling is known to be a very efficient mode of heat transfer, and as such, it is employed in component cooling and in various energy-conversion systems. In space, boiling heat transfer may be used in thermal management, fluid handling and control, power systems, and on-orbit storage and supply systems for cryogenic propellants and life-support fluids. Recent interest in the exploration of Mars and other planets and in the concept of in situ resource utilization on the Martian and Lunar surfaces highlights the need to understand how gravity levels varying from the Earth's gravity to microgravity (1g = or > g/g(sub e) = or > 10(exp -6)g) affect boiling heat transfer. Because of the complex nature of the boiling process, no generalized prediction or procedure has been developed to describe the boiling heat transfer coefficient, particularly at reduced gravity levels. Recently, Professor Vijay K. Dhir of the University of California at Los Angeles proposed a novel building-block approach to investigate the boiling phenomena in low-gravity to microgravity environments. This approach experimentally investigates the complete process of bubble inception, growth, and departure for single bubbles formed at a well-defined and controllable nucleation site. Principal investigator Professor Vijay K. Dhir, with support from researchers from the NASA Glenn Research Center at Lewis Field, is performing a series of pool boiling experiments in the low-gravity environments of the KC 135 microgravity aircraft s parabolic flight to investigate the inception, growth, departure, and merger of bubbles from single- and multiple-nucleation sites as a function of the wall superheat and the liquid subcooling. Silicon wafers with single and multiple cavities of known characteristics are being used as test surfaces. Water and PF5060 (an inert liquid) were chosen as test liquids so that the role of surface wettability and the magnitude of the effect of interfacial tension on boiling in reduced

Preliminary Heat Transfer Studies for the Double Shell Tanks (DST) Transfer Piping

International Nuclear Information System (INIS)

HECHT, S.L.

2000-01-01

Heat transfer studies were made to determine the thermal characteristics of double-shell tank transfer piping under both transient and steady-state conditions. A number of design and operation options were evaluated for this piping system which is in its early design phase

Covalent modification of graphene and graphite using diazonium chemistry: tunable grafting and nanomanipulation.

Science.gov (United States)

Greenwood, John; Phan, Thanh Hai; Fujita, Yasuhiko; Li, Zhi; Ivasenko, Oleksandr; Vanderlinden, Willem; Van Gorp, Hans; Frederickx, Wout; Lu, Gang; Tahara, Kazukuni; Tobe, Yoshito; Uji-I, Hiroshi; Mertens, Stijn F L; De Feyter, Steven

2015-05-26

We shine light on the covalent modification of graphite and graphene substrates using diazonium chemistry under ambient conditions. We report on the nature of the chemical modification of these graphitic substrates, the relation between molecular structure and film morphology, and the impact of the covalent modification on the properties of the substrates, as revealed by local microscopy and spectroscopy techniques and electrochemistry. By careful selection of the reagents and optimizing reaction conditions, a high density of covalently grafted molecules is obtained, a result that is demonstrated in an unprecedented way by scanning tunneling microscopy (STM) under ambient conditions. With nanomanipulation, i.e., nanoshaving using STM, surface structuring and functionalization at the nanoscale is achieved. This manipulation leads to the removal of the covalently anchored molecules, regenerating pristine sp(2) hybridized graphene or graphite patches, as proven by space-resolved Raman microscopy and molecular self-assembly studies.

Pore channel surface modification for enhancing anti-fouling membrane distillation

Science.gov (United States)

Qiu, Haoran; Peng, Yuelian; Ge, Lei; Villacorta Hernandez, Byron; Zhu, Zhonghua

2018-06-01

Membrane surface modification by forming a functional layer is an effective way to improve the anti-fouling properties of membranes; however, the additional layer and the potential blockage of bulk pores may increase the mass transfer resistance and reduce the permeability. In this study, we applied a novel method of preparing anti-fouling membranes for membrane distillation by dispersing graphene oxide (GO) on the channel surface of polyvinylidene fluoride membranes. The surface morphology and properties were characterized by scanning electron microscopy, atomic force microscope, and Fourier transform infrared spectrometry. Compared to the membrane surface modification by nanoparticles (e.g. SiO2), GO was mainly located on the pore surface of the membrane bulk, rather than being formed as an individual layer onto the membrane surface. The performance was evaluated via a direct-contact membrane distillation process with anionic and cationic surfactants as the foulants, separately. Compared to the pristine PVDF membrane, the anti-fouling behavior and distillate flux of the GO-modified membranes were improved, especially when using the anionic surfactant as the foulant. The enhanced anti-fouling performance can be attributed to the oxygen containing functional groups in GO and the healing of the membrane pore defects. This method may provide an effective route to manipulate membrane pore surface properties for anti-fouling separation without increasing mass transfer resistance.

Mathematical Simulation of the Process of Aerobic Treatment of Wastewater under Conditions of Diffusion and Mass Transfer Perturbations

Science.gov (United States)

Bomba, A. Ya.; Safonik, A. P.

2018-03-01

A mathematical model of the process of aerobic treatment of wastewater has been refined. It takes into account the interaction of bacteria, as well as of organic and biologically nonoxidizing substances under conditions of diffusion and mass transfer perturbations. An algorithm of the solution of the corresponding nonlinear perturbed problem of convection-diffusion-mass transfer type has been constructed, with a computer experiment carried out based on it. The influence of the concentration of oxygen and of activated sludge on the quality of treatment is shown. Within the framework of the model suggested, a possibility of automated control of the process of deposition of impurities in a biological filter depending on the initial parameters of the water medium is suggested.

Mathematical Simulation of the Process of Aerobic Treatment of Wastewater under Conditions of Diffusion and Mass Transfer Perturbations

Science.gov (United States)

Bomba, A. Ya.; Safonik, A. P.

2018-05-01

A mathematical model of the process of aerobic treatment of wastewater has been refined. It takes into account the interaction of bacteria, as well as of organic and biologically nonoxidizing substances under conditions of diffusion and mass transfer perturbations. An algorithm of the solution of the corresponding nonlinear perturbed problem of convection-diffusion-mass transfer type has been constructed, with a computer experiment carried out based on it. The influence of the concentration of oxygen and of activated sludge on the quality of treatment is shown. Within the framework of the model suggested, a possibility of automated control of the process of deposition of impurities in a biological filter depending on the initial parameters of the water medium is suggested.

Effects of calcium, potassium, rubidium and various fertilizers on radiocaesium transfers in field and experimental conditions

International Nuclear Information System (INIS)

Mitchell, N.G.; Coughtrey, P.J.; Kirton, J.A.

1990-01-01

To provide a basis for estimating the effectiveness of various treatments in reducing radiocaesium transfer to vegetation and grazing animals in upland ecosystems, studies have been undertaken to determine interactions between radiocaesium transfer and that of analogous elements (e.g. Rb, K) and the effects of various inorganic fertilizers (lime, NPK at different rates). Laboratory results demonstrated Rb and K (at equivalent ionic concentrations) tended to reduce radiocaesium concentrations in vegetation. These effects were highly dependent on the particular combination of plant species and soil conditions. Field investigations showed that potassium reduced radiocaesium concentrations in vegetation only very slightly. Though statistically significant, this effect was insufficient a basis to recommend the use of potassium treatments to ameliorate the effects of deposited radiocaesium. Studies at sites with a known history of land management prior to, or after, the Chernobyl accident show the effect of liming, ancient drainage, and application of organic and inorganic fertilizers. (author)

Characterizing the Range of Extracellular Protein Post-Translational Modifications in a Cellulose-Degrading Bacteria Using a Multiple Proteolyic Digestion/Peptide Fragmentation Approach

Energy Technology Data Exchange (ETDEWEB)

Dykstra, Andrew B [ORNL; Rodriguez, Jr., Miguel [ORNL; Raman, Babu [Dow Chemical Company, The; Cook, Kelsey [ORNL; Hettich, Robert {Bob} L [ORNL

2013-01-01

Post-translational modifications (PTMs) are known to play a significant role in many biological functions. The focus of this study is to characterize the post-translational modifications of the cellulosome protein complex used by the bacterium Clostridium thermocellum to better understand how this protein machine is tuned for enzymatic cellulose solubilization. To enhance comprehensive characterization, the extracellular cellulosome proteins were analyzed using multiple proteolytic digests (trypsin, Lys-C, Glu-C) and multiple fragmentation techniques (collisionally-activated dissociation, electron transfer dissociation, decision tree). As expected, peptide and protein identifications were increased by utilizing alternate proteases and fragmentation methods, in addition to the increase in protein sequence coverage. The complementarity of these experiments also allowed for a global exploration of PTMs associated with the cellulosome based upon a set of defined PTMs that included methylation, oxidation, acetylation, phosphorylation, and signal peptide cleavage. In these experiments, 85 modified peptides corresponding to 28 cellulosome proteins were identified. Many of these modifications were located in active cellulolytic or structural domains of the cellulosome proteins, suggesting a level of possible regulatory control of protein function in various cellulotyic conditions. The use of multiple enzymes and fragmentation technologies allowed for independent verification of PTMs in different experiments, thus leading to increased confidence in PTM identifications.

Surface Modification of Nanoporous 1,2-Polybutadiene by Atom Transfer Radical Polymerization or Click Chemistry

DEFF Research Database (Denmark)

Guo, Fengxiao; Jankova Atanasova, Katja; Schulte, Lars

2010-01-01

ATRP-grafting of hydrophilic polyacrylates and click of MPEG, the originally hydrophobic samples transformed into hydrophilic nanoporous materials. The successful modification was confirmed by infrared spectroscopy, contact angle measurements and measurements of spontaneous water uptake, while...... the morphology was investigated by small-angle X-ray scattering and transmission electron microscopy....

Examining the Costs and Benefits of Family Rewards 2.0: A Conditional Cash Transfer Program in Two American Cities

Science.gov (United States)

Rudd, Timothy; Rodriguez, Jonathan; Greenberg, David

2016-01-01

Family Rewards was an innovative approach to poverty reduction in the United States that was modelled on the conditional cash transfer (CCT) programs common in lower- and middle-income countries. The program offered cash assistance to poor families to reduce immediate hardship, provided they met certain criteria related to family health care,…

Using Incentives to Change How Teenagers Spend Their Time: The Effects of New York City's Conditional Cash Transfer Program

Science.gov (United States)

Morris, Pamela; Aber, J. Lawrence; Wolf, Sharon; Berg, Juliette

2012-01-01

This report presents the results of an innovative study designed to provide a more detailed understanding of how parents and their teenage children were affected by the Opportunity NYC-Family Rewards program, a comprehensive conditional cash transfer program. The three-year program, launched by the Center for Economic Opportunity in the Mayor's…

Polymeric film application for phase change heat transfer

Science.gov (United States)

Bart, Hans-Jörg; Dreiser, Christian

2018-06-01

The paper gives a concise review on polymer film heat exchangers (PFHX) with a focus on polyether ether ketone (PEEK) foil as heat transfer element, mechanically supported by a grid structure. In order to promote PFHX applications, heat transfer performance and wetting behavior are studied in detail. Surface modifications to improve wetting are discussed and correlations are presented for critical Reynolds numbers to sustain a stable liquid film. Scaling phenomena related to surface properties and easily adaptable cleaning-in-place (CIP) procedures are further content. The contribution of the foil thickness and material selection on thermal performance is quantified and a correlation for enhanced aqueous film heat transfer for the grid supported PFHX is given. The basic research results and the design criteria enable early stage material selection and conceptual apparatus design.

Polymeric film application for phase change heat transfer

Science.gov (United States)

Bart, Hans-Jörg; Dreiser, Christian

2018-01-01

The paper gives a concise review on polymer film heat exchangers (PFHX) with a focus on polyether ether ketone (PEEK) foil as heat transfer element, mechanically supported by a grid structure. In order to promote PFHX applications, heat transfer performance and wetting behavior are studied in detail. Surface modifications to improve wetting are discussed and correlations are presented for critical Reynolds numbers to sustain a stable liquid film. Scaling phenomena related to surface properties and easily adaptable cleaning-in-place (CIP) procedures are further content. The contribution of the foil thickness and material selection on thermal performance is quantified and a correlation for enhanced aqueous film heat transfer for the grid supported PFHX is given. The basic research results and the design criteria enable early stage material selection and conceptual apparatus design.

Laser surface modification of PEEK

Energy Technology Data Exchange (ETDEWEB)

Riveiro, A., E-mail: ariveiro@uvigo.es [Applied Physics Department, University of Vigo ETSII, Lagoas-Marcosende, 9, Vigo 36310 (Spain); Centro Universitario de la Defensa, Escuela Naval Militar, Plaza de Espana 2, 36920 Marin (Spain); Soto, R.; Comesana, R.; Boutinguiza, M.; Val, J. del; Quintero, F.; Lusquinos, F.; Pou, J. [Applied Physics Department, University of Vigo ETSII, Lagoas-Marcosende, 9, Vigo 36310 (Spain)

2012-09-15

Highlights: Black-Right-Pointing-Pointer Role of laser irradiation wavelength on the surface modification of PEEK (polyether-ether-ketone) was investigated. Black-Right-Pointing-Pointer Adequate processing conditions to improve wettability, roughness, and cell adhesion characteristics are determined. Black-Right-Pointing-Pointer A design of experiments (DOE) methodology was performed. Black-Right-Pointing-Pointer UV (355 nm) radiation is the most promising laser radiation for improving the adhesive surface properties of PEEK. - Abstract: Polyether-ether-ketone (PEEK) is a synthetic thermoplastic polymer with excellent mechanical and chemical properties, which make it attractive for the field of reconstructive surgery. Nevertheless, this material has a poor interfacial biocompatibility due to its large chemical stability which induces poor adhesive bonding properties. The possibilities of enhancing the PEEK adhesive properties by laser treatments have been explored in the past. This paper presents a systematic approach to discern the role of laser irradiation wavelength on the surface modification of PEEK under three laser wavelengths ({lambda} = 1064, 532, and 355 nm) with the aim to determine the most adequate processing conditions to increase the roughness and wettability, the main parameters affecting cell adhesion characteristics of implants. Overall results show that the ultraviolet ({lambda} = 355 nm) laser radiation is the most suitable one to enhance surface wettability of PEEK.

Modification of an impulse-factoring orbital transfer technique to account for orbit determination and maneuver execution errors

Science.gov (United States)

Kibler, J. F.; Green, R. N.; Young, G. R.; Kelly, M. G.

1974-01-01

A method has previously been developed to satisfy terminal rendezvous and intermediate timing constraints for planetary missions involving orbital operations. The method uses impulse factoring in which a two-impulse transfer is divided into three or four impulses which add one or two intermediate orbits. The periods of the intermediate orbits and the number of revolutions in each orbit are varied to satisfy timing constraints. Techniques are developed to retarget the orbital transfer in the presence of orbit-determination and maneuver-execution errors. Sample results indicate that the nominal transfer can be retargeted with little change in either the magnitude (Delta V) or location of the individual impulses. Additonally, the total Delta V required for the retargeted transfer is little different from that required for the nominal transfer. A digital computer program developed to implement the techniques is described.

Shock modification and chemistry and planetary geologic processes

International Nuclear Information System (INIS)

Boslough, M.S.

1991-01-01

This paper brings the rapid advances on shock processing of materials to the attention of Earth scientists, and to put these advances in the context of planetary geologic processes. Most of the recent research in this area has been directed at materials modification an synthesis, and the information gained has direct relevance to shock effects in nature. Research on various types of shock modification and chemistry in both naturally and experimentally shocked rocks and minerals is reviewed, and where appropriate their significance to planetary processes is indicated. As a case study, the surface of Mars is suggested as a place where conditions are optimal for shock processing to be a dominant factor. The various mechanisms of shock modification, activation, synthesis and decomposition are all proposed as major contributors to the evolution of chemical, mineralogical, and physical properties of the Martian regolith

Modification of Jute Fibers with Polystyrene via Atom Transfer Radical Polymerization

DEFF Research Database (Denmark)

Plackett, David; Jankova, Katja Atanassova; Egsgaard, Helge

2005-01-01

Atom transfer radical polymerization (ATRP) was investigated as a method of covalently bonding polystyrene to jute (Corchorus capsularis) and as a possible approach to fiber composites with enhanced properties. Jute fibers were modified with a brominated initiator and subsequently ATRP modified...... to attach polystyrene and then examined using SEM, DSC, TGA, FTIR, XPS, elemental analysis, and Py-GC-MS. These techniques confirmed that polystyrene had been covalently bound to the fibers and consequently ATRP-modified jute fiber mats were used to prepare hot-pressed polystyrene composites. Composite...

Modification of GNPS environment radiation monitoring network system

International Nuclear Information System (INIS)

Jiang Lili; Cao Chunsheng

1999-01-01

GNPS Environment Radiation Continuous Monitoring System (KRS), the only real time on-line system of site radiation monitoring, was put into service in 1993 prior to the first loading the the plant. It is revealed through several years of operation that this system has some deficiencies such as inadequate real time monitoring means, no figure and diagram display function on the central computer, high failures, frequent failure warning signals, thus making the availability of the system at a low level. In recent years, with the rapid development of computer network technology and increasingly strict requirements on the NPP environment protection raised by the government and public, KRS modification had become necessary and urgent. In 1996, GNPS carried out modification work on the measuring geometry condition of γ radiation monitoring sub-station and lightening protection. To enhance the functions of real time monitoring and data auto-processing, further modification of the system was made in 1998, including the update of the software and hardware of KRS central processor, set-up of system computer local network and database. In this way, the system availability and monitoring quality are greatly improved and effective monitoring and analysis means are provided for gaseous release during normal operation and under accident condition

From Olive Fruits to Olive Oil: Phenolic Compound Transfer in Six Different Olive Cultivars Grown under the Same Agronomical Conditions.

Science.gov (United States)

Talhaoui, Nassima; Gómez-Caravaca, Ana María; León, Lorenzo; De la Rosa, Raúl; Fernández-Gutiérrez, Alberto; Segura-Carretero, Antonio

2016-03-04

Phenolic compounds are responsible of the nutritional and sensory quality of extra-virgin olive oil (EVOO). The composition of phenolic compounds in EVOO is related to the initial content of phenolic compounds in the olive-fruit tissues and the activity of enzymes acting on these compounds during the industrial process to produce the oil. In this work, the phenolic composition was studied in six major cultivars grown in the same orchard under the same agronomical and environmental conditions in an effort to test the effects of cultivars on phenolic composition in fruits and oils as well as on transfer between matrices. The phenolic fractions were identified and quantified using high-performance liquid chromatography-diode array detector-time-of-flight-mass spectrometry. A total of 33 phenolic compounds were determined in the fruit samples and a total of 20 compounds in their corresponding oils. Qualitative and quantitative differences in phenolic composition were found among cultivars in both matrices, as well as regarding the transfer rate of phenolic compounds from fruits to oil. The results also varied according to the different phenolic groups evaluated, with secoiridoids registering the highest transfer rates from fruits to oils. Moreover, wide-ranging differences have been noticed between cultivars for the transfer rates of secoiridoids (4.36%-65.63% of total transfer rate) and for flavonoids (0.18%-0.67% of total transfer rate). 'Picual' was the cultivar that transferred secoiridoids to oil at the highest rate, whereas 'Changlot Real' was the cultivar that transferred flavonoids at the highest rates instead. Principal-component analysis confirmed a strong genetic effect on the basis of the phenolic profile both in the olive fruits and in the oils.

Surface-Initiated Graft Atom Transfer Radical Polymerization of Methyl Methacrylate from Chitin Nanofiber Macroinitiator under Dispersion Conditions

Directory of Open Access Journals (Sweden)

Ryo Endo

2015-08-01

Full Text Available Surface-initiated graft atom transfer radical polymerization (ATRP of methyl methacrylate (MMA from self-assembled chitin nanofibers (CNFs was performed under dispersion conditions. Self-assembled CNFs were initially prepared by regeneration from a chitin ion gel with 1-allyl-3-methylimidazolium bromide using methanol; the product was then converted into the chitin nanofiber macroinitiator by reaction with α-bromoisobutyryl bromide in a dispersion containing N,N-dimethylformamide. Surface-initiated graft ATRP of MMA from the initiating sites on the CNFs was subsequently carried out under dispersion conditions, followed by filtration to obtain the CNF-graft-polyMMA film. Analysis of the product confirmed the occurrence of the graft ATRP on the surface of the CNFs.

Modification of poly(styrene-block-butadiene-block-styrene) [SBS] with phosphorus containing fire retardants

DEFF Research Database (Denmark)

Chernyy, Sergey; Ullah, Saif; Jomaas, Grunde

2015-01-01

An elaborate survey of the chemical modification methods for endowing highly flammable SBS with increased fire resistant properties by means of chemical modification of the polymer backbone with phosphorus containing fire retardant species is presented. Optimal conditions for free radical addition...

A new setup for the investigation of swift heavy ion induced particle emission and surface modifications

Energy Technology Data Exchange (ETDEWEB)

Meinerzhagen, F.; Breuer, L.; Bukowska, H.; Herder, M.; Schleberger, M.; Wucher, A. [Fakultät für Physik, Universität Duisburg-Essen and Cenide, 47057 Duisburg (Germany); Bender, M.; Severin, D. [GSI Helmholtzzentrum für Schwerionenforschung GmbH, 64291 Darmstadt (Germany); Lebius, H. [CIMAP (CEA-CNRS-ENSICAEN-UCN), 14070 Caen Cedex 5 (France)

2016-01-15

The irradiation with fast ions with kinetic energies of >10 MeV leads to the deposition of a high amount of energy along their trajectory (up to several ten keV/nm). The energy is mainly transferred to the electronic subsystem and induces different secondary processes of excitations, which result in significant material modifications. A new setup to study these ion induced effects on surfaces will be described in this paper. The setup combines a variable irradiation chamber with different techniques of surface characterizations like scanning probe microscopy, time-of-flight secondary ion, and neutral mass spectrometry, as well as low energy electron diffraction under ultra high vacuum conditions, and is mounted at a beamline of the universal linear accelerator (UNILAC) of the GSI facility in Darmstadt, Germany. Here, samples can be irradiated with high-energy ions with a total kinetic energy up to several GeVs under different angles of incidence. Our setup enables the preparation and in situ analysis of different types of sample systems ranging from metals to insulators. Time-of-flight secondary ion mass spectrometry enables us to study the chemical composition of the surface, while scanning probe microscopy allows a detailed view into the local electrical and morphological conditions of the sample surface down to atomic scales. With the new setup, particle emission during irradiation as well as persistent modifications of the surface after irradiation can thus be studied. We present first data obtained with the new setup, including a novel measuring protocol for time-of-flight mass spectrometry with the GSI UNILAC accelerator.

Suction blister grafting - Modifications for easy harvesting and grafting

Directory of Open Access Journals (Sweden)

2012-01-01

Full Text Available Suction blister grafting is a simple modality of treatment of patients with resistant and stable vitiligo. But raising the blisters may be time consuming and transferring to the recipient site may be difficult as the graft is ultrathin. By doing some modifications we can make the technique simpler and easier. We can decrease the blister induction time by intradermal injection of saline, exposure to Wood′s lamp, intrablister injection of saline. By these methods we can decrease the blister induction time from 2-3 hrs to 45-90 minutes. After harvesting the graft, it can be transferred to the recipient area by taking the graft on a sterile glass slide, on the gloved finger, rolling the graft over a sterile syringe and then spreading on the recipient area, or taking on the sterile wrapper of paraffin dressing and then placing over the recipient area.

Effects of etchants in the transfer of chemical vapor deposited graphene

Science.gov (United States)

Wang, M.; Yang, E. H.; Vajtai, R.; Kono, J.; Ajayan, P. M.

2018-05-01

The quality of graphene can be strongly modified during the transfer process following chemical vapor deposition (CVD) growth. Here, we transferred CVD-grown graphene from a copper foil to a SiO2/Si substrate using wet etching with four different etchants: HNO3, FeCl3, (NH4)2S2O8, and a commercial copper etchant. We then compared the quality of graphene after the transfer process in terms of surface modifications, pollutions (residues and contaminations), and electrical properties (mobility and density). Our tests and analyses showed that the commercial copper etchant provides the best structural integrity, the least amount of residues, and the smallest doping carrier concentration.

The impact of conditional cash transfers on health outcomes and use of health services in low and middle income countries.

Science.gov (United States)

Lagarde, Mylene; Haines, Andy; Palmer, Natasha

2009-10-07

Conditional cash transfers (CCT) provide monetary transfers to households on the condition that they comply with some pre-defined requirements. CCT programmes have been justified on the grounds that demand-side subsidies are necessary to address inequities in access to health and social services for poor people. In the past decade they have become increasingly popular, particularly in middle income countries in Latin America. To assess the effectiveness of CCT in improving access to care and health outcomes, in particular for poorer populations in low and middle income countries. We searched a wide range of international databases, including the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE and EMBASE, in addition to development studies and economic databases. We also searched the websites and online resources of numerous international agencies, organisations and universities to find relevant grey literature. The original searches were conducted between November 2005 and April 2006. An updated search in MEDLINE was carried out in May 2009. CCT were defined as monetary transfers made to households on the condition that they comply with some pre-determined requirements in relation to health care. Studies had to include an objective measure of at least one of the following outcomes: health care utilisation, health expenditure, health outcomes or equity outcomes. Eligible study designs were: randomised controlled trial, interrupted time series analysis, or controlled before-after study of the impact of health financing policies following criteria used by the Cochrane Effective Practice and Organisation of Care Group. We performed qualitative analysis of the evidence. We included ten papers reporting results from six intervention studies. Overall, design quality and analysis limited the risks of bias. Several CCT programmes provided strong evidence of a positive impact on the use of health services, nutritional status and health outcomes

IMPROVEMENT OF ACCURACY OF RADIATIVE HEAT TRANSFER DIFFERENTIAL APPROXIMATION METHOD FOR MULTI DIMENSIONAL SYSTEMS BY MEANS OF AUTO-ADAPTABLE BOUNDARY CONDITIONS

Directory of Open Access Journals (Sweden)

K. V. Dobrego

2015-01-01

Full Text Available Differential approximation is derived from radiation transfer equation by averaging over the solid angle. It is one of the more effective methods for engineering calculations of radia- tive heat transfer in complex three-dimensional thermal power systems with selective and scattering media. The new method for improvement of accuracy of the differential approximation based on using of auto-adaptable boundary conditions is introduced in the paper. The  efficiency  of  the  named  method  is  proved  for  the  test  2D-systems.  Self-consistent auto-adaptable boundary conditions taking into consideration the nonorthogonal component of the incident to the boundary radiation flux are formulated. It is demonstrated that taking in- to consideration of the non- orthogonal incident flux in multi-dimensional systems, such as furnaces, boilers, combustion chambers improves the accuracy of the radiant flux simulations and to more extend in the zones adjacent to the edges of the chamber.Test simulations utilizing the differential approximation method with traditional boundary conditions, new self-consistent boundary conditions and “precise” discrete ordinates method were performed. The mean square errors of the resulting radiative fluxes calculated along the boundary of rectangular and triangular test areas were decreased 1.5–2 times by using auto- adaptable boundary conditions. Radiation flux gaps in the corner points of non-symmetric sys- tems are revealed by using auto-adaptable boundary conditions which can not be obtained by using the conventional boundary conditions.

Foreign transfers and tropical deforestation : What terms of conditionality?

NARCIS (Netherlands)

van Soest, D; Lensink, R

The international community considers the possibility of using aid as an instrument to improve natural resource conservation in developing countries. By making the amount of transfers dependent on the efforts of the recipient countries to improve conservation, appropriate incentives can be given. We

Guidance on the implementation of modifications to mitigate beyond design basis accidents

Energy Technology Data Exchange (ETDEWEB)

Harris, S.; Marczak, J.; O' Neill, M. [Ontario Power Generation, Pickering, ON (Canada)

2014-07-01

Following the events at Fukushima, Canadian Nuclear Power Plants (NPP) procured equipment and initiated modifications to improve response capability for Beyond Design Basis Accidents (BDBA). These changes were not typical of other design modifications to the nuclear power plants and reinforced the need for additional guidance for modifications to address BDBA. This paper describes the guidance that was developed to guide the design, procurement, installation, operation, and maintenance of equipment and modifications to mitigate BDBAs. The guidance developed prescribes a graded approach based on a categorization of the nature of the modification. Four categories of modifications are introduced, with the distinction being the degree of interface with existing design basis systems, structures and components (SSCs). This has resulted in a cost-effective means of implementing additional capability to mitigate BDBA conditions, and yet ensure the design basis capability of SSCs is maintained. Operating experience with use of the guidance is also discussed. (author)

Guidance on the implementation of modifications to mitigate beyond design basis accidents

International Nuclear Information System (INIS)

Harris, S.; Marczak, J.; O'Neill, M.

2014-01-01

Following the events at Fukushima, Canadian Nuclear Power Plants (NPP) procured equipment and initiated modifications to improve response capability for Beyond Design Basis Accidents (BDBA). These changes were not typical of other design modifications to the nuclear power plants and reinforced the need for additional guidance for modifications to address BDBA. This paper describes the guidance that was developed to guide the design, procurement, installation, operation, and maintenance of equipment and modifications to mitigate BDBAs. The guidance developed prescribes a graded approach based on a categorization of the nature of the modification. Four categories of modifications are introduced, with the distinction being the degree of interface with existing design basis systems, structures and components (SSCs). This has resulted in a cost-effective means of implementing additional capability to mitigate BDBA conditions, and yet ensure the design basis capability of SSCs is maintained. Operating experience with use of the guidance is also discussed. (author)

Reactive modification of polyesters and their blends

Science.gov (United States)

Wan, Chen

2004-12-01

As part of a broader research effort to investigate the chemical modification of polyesters by reactive processing a low molecular weight (MW) unsaturated polyester (UP) and a higher MW saturated polyester, polyethylene terephthalate (PET), alone or blended with polypropylene (PP) were melt processed in a batch mixer and continuous twin screw extruders. Modification was monitored by on-line rheology and the products were characterized primarily by off-line rheology, morphology and thermal analysis. Efforts were made to establish processing/property relationships and provide an insight of the accompanying structural changes. The overall response of the reactively modified systems was found to be strongly dependent on the component characteristics, blend composition, type and concentrations of reactive additives and processing conditions. The work concluded that UP can be effectively modified through reactive melt processing. Its melt viscosity and MW can be increased through chemical reactions between organic peroxides (POX) and chain unsaturation or between MgO and carboxyl/hydroxyl end groups. Reactive blending of PP/UP blends through peroxide modification gave finer and more uniform morphology than unreacted blends and at a given PP/UP weight ratio more thermoplastic elastomers-like rheological behavior. This is due to the continuously decreasing viscosity ratio of PP/UP towards unity by the competing reactions between POX and the blend components and formation of PP-UP copolymers which serve as in-situ compatibilizers to promote better interfacial adhesion. Kinetics of the competing reactions were analyzed through a developed model. In addition to POX concentration and mixing efficiency, rheology and morphology of UP/PP bends were significantly affected by the addition of inorganic and organic coagents. Addition of coagents such as a difunctional maleimide, MgO and/or an anhydride functionalized PP during reactive blending offers effective means for tailoring

From Olive Fruits to Olive Oil: Phenolic Compound Transfer in Six Different Olive Cultivars Grown under the Same Agronomical Conditions

Directory of Open Access Journals (Sweden)

Nassima Talhaoui

2016-03-01

Full Text Available Phenolic compounds are responsible of the nutritional and sensory quality of extra-virgin olive oil (EVOO. The composition of phenolic compounds in EVOO is related to the initial content of phenolic compounds in the olive-fruit tissues and the activity of enzymes acting on these compounds during the industrial process to produce the oil. In this work, the phenolic composition was studied in six major cultivars grown in the same orchard under the same agronomical and environmental conditions in an effort to test the effects of cultivars on phenolic composition in fruits and oils as well as on transfer between matrices. The phenolic fractions were identified and quantified using high-performance liquid chromatography-diode array detector-time-of-flight-mass spectrometry. A total of 33 phenolic compounds were determined in the fruit samples and a total of 20 compounds in their corresponding oils. Qualitative and quantitative differences in phenolic composition were found among cultivars in both matrices, as well as regarding the transfer rate of phenolic compounds from fruits to oil. The results also varied according to the different phenolic groups evaluated, with secoiridoids registering the highest transfer rates from fruits to oils. Moreover, wide-ranging differences have been noticed between cultivars for the transfer rates of secoiridoids (4.36%–65.63% of total transfer rate and for flavonoids (0.18%–0.67% of total transfer rate. ‘Picual’ was the cultivar that transferred secoiridoids to oil at the highest rate, whereas ‘Changlot Real’ was the cultivar that transferred flavonoids at the highest rates instead. Principal-component analysis confirmed a strong genetic effect on the basis of the phenolic profile both in the olive fruits and in the oils.

Analysis of the dual phase lag bio-heat transfer equation with constant and time-dependent heat flux conditions on skin surface

Directory of Open Access Journals (Sweden)

Ziaei Poor Hamed

2016-01-01

Full Text Available This article focuses on temperature response of skin tissue due to time-dependent surface heat fluxes. Analytical solution is constructed for DPL bio-heat transfer equation with constant, periodic and pulse train heat flux conditions on skin surface. Separation of variables and Duhamel’s theorem for a skin tissue as a finite domain are employed. The transient temperature responses for constant and time-dependent boundary conditions are obtained and discussed. The results show that there is major discrepancy between the predicted temperature of parabolic (Pennes bio-heat transfer, hyperbolic (thermal wave and DPL bio-heat transfer models when high heat flux accidents on the skin surface with a short duration or propagation speed of thermal wave is finite. The results illustrate that the DPL model reduces to the hyperbolic model when τT approaches zero and the classic Fourier model when both thermal relaxations approach zero. However for τq = τT the DPL model anticipates different temperature distribution with that predicted by the Pennes model. Such discrepancy is due to the blood perfusion term in energy equation. It is in contrast to results from the literature for pure conduction material, where the DPL model approaches the Fourier heat conduction model when τq = τT . The burn injury is also investigated.

Modification of cellulose with succinic anhydride in TBAA/DMSO mixed solvent under catalyst-free conditions

Science.gov (United States)

Homogeneous modification of cellulose with succinic anhydride was performed in tetrabutylammonium acetate (TBAA)/dimethyl sulfoxide (DMSO) mixed solvent. The molar ratio of succinic anhydride (SA) to free hydroxyl groups in the anhydroglucose units (AGU) and TBAA dosage were investigated as paramete...

Operant Conditioning for Special Educators.

Science.gov (United States)

Pedrini, Bonnie C.; Pedrini, D. T.

The paper briefly explains operant conditioning as it pertains to special educators. Operant conditioning is thought to be an efficient method for modifying student behavior. Using the B. F. Skinner frame of reference, operant conditioning is said to include behavior modification and therapy, programed instruction, and computer assisted and…

Time-resolved energy transfer from single chloride-terminated nanocrystals to graphene

International Nuclear Information System (INIS)

Ajayi, O. A.; Wong, C. W.; Anderson, N. C.; Wolcott, A.; Owen, J. S.; Cotlet, M.; Petrone, N.; Hone, J.; Gu, T.; Gesuele, F.

2014-01-01

We examine the time-resolved resonance energy transfer of excitons from single n-butyl amine-bound, chloride-terminated nanocrystals to two-dimensional graphene through time-correlated single photon counting. The radiative biexponential lifetime kinetics and blinking statistics of the individual surface-modified nanocrystal elucidate the non-radiative decay channels. Blinking modification as well as a 4× reduction in spontaneous emission were observed with the short chloride and n-butylamine ligands, probing the energy transfer pathways for the development of graphene-nanocrystal nanophotonic devices

Time-resolved energy transfer from single chloride-terminated nanocrystals to graphene

Energy Technology Data Exchange (ETDEWEB)

Ajayi, O. A., E-mail: oaa2114@columbia.edu, E-mail: cww2104@columbia.edu; Wong, C. W., E-mail: oaa2114@columbia.edu, E-mail: cww2104@columbia.edu [Optical Nanostructures Laboratory, Center for Integrated Science and Engineering, Solid-State Science and Engineering, Columbia University, New York, New York 10027 (United States); Department of Mechanical Engineering, Columbia University, New York, New York 10027 (United States); Anderson, N. C.; Wolcott, A.; Owen, J. S. [Department of Chemistry, Columbia University, New York, New York 10027 (United States); Cotlet, M. [Brookhaven National Laboratory, Upton, New York, New York 11973 (United States); Petrone, N.; Hone, J. [Department of Mechanical Engineering, Columbia University, New York, New York 10027 (United States); Gu, T.; Gesuele, F. [Optical Nanostructures Laboratory, Center for Integrated Science and Engineering, Solid-State Science and Engineering, Columbia University, New York, New York 10027 (United States)

2014-04-28

We examine the time-resolved resonance energy transfer of excitons from single n-butyl amine-bound, chloride-terminated nanocrystals to two-dimensional graphene through time-correlated single photon counting. The radiative biexponential lifetime kinetics and blinking statistics of the individual surface-modified nanocrystal elucidate the non-radiative decay channels. Blinking modification as well as a 4× reduction in spontaneous emission were observed with the short chloride and n-butylamine ligands, probing the energy transfer pathways for the development of graphene-nanocrystal nanophotonic devices.

Automatic braking system modification for the Advanced Transport Operating Systems (ATOPS) Transportation Systems Research Vehicle (TSRV)

Science.gov (United States)

Coogan, J. J.

1986-01-01

Modifications were designed for the B-737-100 Research Aircraft autobrake system hardware of the Advanced Transport Operating Systems (ATOPS) Program at Langley Research Center. These modifications will allow the on-board flight control computer to control the aircraft deceleration after landing to a continuously variable level for the purpose of executing automatic high speed turn-offs from the runway. A bread board version of the proposed modifications was built and tested in simulated stopping conditions. Test results, for various aircraft weights, turnoff speed, winds, and runway conditions show that the turnoff speeds are achieved generally with errors less than 1 ft/sec.

Mass transfer inside oblate spheroidal solids: modelling and simulation

Directory of Open Access Journals (Sweden)

J. E. F. Carmo

2008-03-01

Full Text Available A numerical solution of the unsteady diffusion equation describing mass transfer inside oblate spheroids, considering a constant diffusion coefficient and the convective boundary condition, is presented. The diffusion equation written in the oblate spheroidal coordinate system was used for a two-dimensional case. The finite-volume method was employed to discretize the basic equation. The linear equation set was solved iteratively using the Gauss-Seidel method. As applications, the effects of the Fourier number, the Biot number and the aspect ratio of the body on the drying rate and moisture content during the process are presented. To validate the methodology, results obtained in this work are compared with analytical results of the moisture content encountered in the literature and good agreement was obtained. The results show that the model is consistent and it may be used to solve cases such as those that include disks and spheres and/or those with variable properties with small modifications.

Lattice Boltzmann simulations of heat transfer in fully developed periodic incompressible flows

Science.gov (United States)

Wang, Zimeng; Shang, Helen; Zhang, Junfeng

2017-06-01

Flow and heat transfer in periodic structures are of great interest for many applications. In this paper, we carefully examine the periodic features of fully developed periodic incompressible thermal flows, and incorporate them in the lattice Boltzmann method (LBM) for flow and heat transfer simulations. Two numerical approaches, the distribution modification (DM) approach and the source term (ST) approach, are proposed; and they can both be used for periodic thermal flows with constant wall temperature (CWT) and surface heat flux boundary conditions. However, the DM approach might be more efficient, especially for CWT systems since the ST approach requires calculations of the streamwise temperature gradient at all lattice nodes. Several example simulations are conducted, including flows through flat and wavy channels and flows through a square array with circular cylinders. Results are compared to analytical solutions, previous studies, and our own LBM calculations using different simulation techniques (i.e., the one-module simulation vs. the two-module simulation, and the DM approach vs. the ST approach) with good agreement. These simple, however, representative simulations demonstrate the accuracy and usefulness of our proposed LBM methods for future thermal periodic flow simulations.

The Role of Community Sports Coaches in Creating Optimal Social Conditions for Life Skill Development and Transferability--A Salutogenic Perspective

Science.gov (United States)

Super, Sabina; Verkooijen, Kirsten; Koelen, Maria

2018-01-01

Sport is widely recognised as having the potential to enhance the personal development of socially vulnerable youth, yet there is very limited knowledge on how community sports coaches can create optimal social conditions for life skill development and transferability. We adopt a salutogenic approach in order to study whether and how community…

14 CFR 431.73 - Continuing accuracy of license application; application for modification of license.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Continuing accuracy of license application; application for modification of license. 431.73 Section 431.73 Aeronautics and Space COMMERCIAL SPACE... Conditions § 431.73 Continuing accuracy of license application; application for modification of license. (a...

Chemical and morphological modifications of single layer graphene submitted to annealing in water vapor

Science.gov (United States)

Rolim, Guilherme Koszeniewski; Corrêa, Silma Alberton; Galves, Lauren Aranha; Lopes, João Marcelo J.; Soares, Gabriel Vieira; Radtke, Cláudio

2018-01-01

Modifications of single layer graphene transferred to SiO2/Si substrates resulting from annealing in water vapor were investigated. Near edge X-ray absorption fine structure spectroscopy evidenced graphene puckering between 400 and 500 °C. Synchrotron radiation based X-ray photoelectron spectroscopy showed variation of sp2 and sp3C bonding configurations specially in this same temperature range. Moreover, oxygen related functionalities are formed as a result of water vapor annealing. Based on these results and complementary Raman and nuclear reaction analysis, one distinguishes three different regimes of water interaction with graphene concerning modifications of the graphene layer. In the low temperature range (200-400 °C), no prominent modification of graphene itself is observed. At higher temperatures (400-500 °C), to accommodate newly formed oxygen functionalities, the flat and continuous sp2 bonding network of graphene is disrupted, giving rise to a puckered layer. For 600 °C and above, shrinking of graphene domains and a higher doping level take place.

Electrophoretic transfer protein zymography.

Science.gov (United States)

Pan, Daniel; Hill, Adam P; Kashou, Anthony; Wilson, Karl A; Tan-Wilson, Anna

2011-04-15

Zymography detects and characterizes proteolytic enzymes by electrophoresis of protease-containing samples into a nonreducing sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) gel containing a copolymerized protein substrate. The usefulness of zymography for molecular weight determination and proteomic analysis is hampered by the fact that some proteases exhibit slower migration through a gel that contains substrate protein. This article introduces electrophoretic transfer protein zymography as one solution to this problem. In this technique, samples containing proteolytic enzymes are first resolved in nonreducing SDS-PAGE on a gel without protein substrate. The proteins in the resolving gel are then electrophoretically transferred to a receiving gel previously prepared with a copolymerized protein substrate. The receiving gel is then developed as a zymogram to visualize clear or lightly stained bands in a dark background. Band intensities are linearly related to the amount of protease, extending the usefulness of the technique so long as conditions for transfer and development of the zymogram are kept constant. Conditions of transfer, such as the pore sizes of resolving and receiving gels and the transfer time relative to the molecular weight of the protease, are explored. Copyright © 2011 Elsevier Inc. All rights reserved.

Evaluation of upward heat flux in ex-vessel molten core heat transfer using MELCOR

International Nuclear Information System (INIS)

Park, S.Y.; Park, J.H.; Kim, S.D.; Kim, D.H.; Kim, H.D.

2000-01-01

The purpose of this study is to share experiences of MELCOR application to resolve the molten corium-concrete interaction (MCCI) issue in the Korea Next Generation Reactor (KNGR). In the evaluation of concrete erosion, the heat transfer modeling from the molten corium internal to the corium pool surface is very important and uncertain. MELCOR employs Kutateladze or Greene's bubble-enhanced heat transfer model for the internal heat transfer. The phenomenological uncertainty is so large that the model provides several model parameters in addition to the phenomenological model for user flexibility. However, the model parameters do not work on Kutateladze correlation at the top of the molten layer. From our experience, a code modification is suggested to match the upward heat flux with the experimental results. In this analysis, minor modification was carried out to calculate heat flux from the top molten layer to corium surface, and efforts were made to find out the best value of the model parameter based on upward heat flux of MACE test M1B. Discussion also includes its application to KNGR. (author)

Behavior modification and pharmacotherapy for separation anxiety in a 2-year-old pointer cross

OpenAIRE

Lem, Michelle

2002-01-01

Separation anxiety is a common behavioral problem in dogs. Treatment is based on developing a behavior modification protocol that gradually desensitizes and counter-conditions the dog to being left alone, by rewarding calm, relaxed behavior. Judicious use of pharmacotherapy can be a useful adjunct to a behavior modification program.

Lysine-Directed Post-translational Modifications of Tau Protein in Alzheimer's Disease and Related Tauopathies

Directory of Open Access Journals (Sweden)

Christiana Kontaxi

2017-08-01

Full Text Available Tau is a microtubule-associated protein responsible mainly for stabilizing the neuronal microtubule network in the brain. Under normal conditions, tau is highly soluble and adopts an “unfolded” conformation. However, it undergoes conformational changes resulting in a less soluble form with weakened microtubule stabilizing properties. Altered tau forms characteristic pathogenic inclusions in Alzheimer's disease and related tauopathies. Although, tau hyperphosphorylation is widely considered to be the major trigger of tau malfunction, tau undergoes several post-translational modifications at lysine residues including acetylation, methylation, ubiquitylation, SUMOylation, and glycation. We are only beginning to define the site-specific impact of each type of lysine modification on tau biology as well as the possible interplay between them, but, like phosphorylation, these modifications are likely to play critical roles in tau's normal and pathobiology. This review summarizes the latest findings focusing on lysine post-translational modifications that occur at both endogenous tau protein and pathological tau forms in AD and other tauopathies. In addition, it highlights the significance of a site-dependent approach of studying tau post-translational modifications under normal and pathological conditions.

Wetting Behavior of Molten AZ61 Magnesium Alloy on Two Different Steel Plates Under the Cold Metal Transfer Condition

Directory of Open Access Journals (Sweden)

ZENG Cheng-zong

2017-04-01

Full Text Available The wetting behavior and interfacial microstructures of molten magnesium AZ61 alloy on the surface of two different Q235 and galvanized steel plates under the condition of cold metal transfer were investigated by using dynamic sessile drop method. The results show that the wetting behavior is closely related to the wire feed speed. Al-Fe intermetallic layer was observed whether the substrate is Q235 steel or galvanized steel, and the formation of Al-Fe intermetallic layer should satisfy the thermodynamic condition of such Mg-Al/Fe system. The wettability of molten AZ61 magnesium alloy is improved with the increase of wire feed speed whether on Q235 steel surface or on galvanized steel surface, good wettability on Q235 steel surface is due to severe interface reaction when wire feed speed increases, good wettability on galvanized steel surface is attributed to the aggravating zinc volatilization. When the wire feed speed is ≤10.5m·min-1, the wettability of Mg alloy on Q235 steel plate is better than on galvanized steel plate. However, Zn vapor will result in instability for metal transfer process.

Elementary heat transfer analysis

CERN Document Server

Whitaker, Stephen; Hartnett, James P

1976-01-01

Elementary Heat Transfer Analysis provides information pertinent to the fundamental aspects of the nature of transient heat conduction. This book presents a thorough understanding of the thermal energy equation and its application to boundary layer flows and confined and unconfined turbulent flows. Organized into nine chapters, this book begins with an overview of the use of heat transfer coefficients in formulating the flux condition at phase interface. This text then explains the specification as well as application of flux boundary conditions. Other chapters consider a derivation of the tra

Evaluation of specific tritium transfer parameters in equilibrium conditions for Cernavoda area

International Nuclear Information System (INIS)

Paunescu, N.; Galeriu, D.; Mocanu, N.; Margineanu, R.

1998-01-01

plants are low, as for an uncontaminated area. The presence of tritium in these samples is due to fallout. Steady-state conditions are achieved for environmental transfer of tritium in absence of local tritium source. Considering the environmental transfer model of Canadian standard, we calculated the transfer parameters for deposition from atmosphere on forage and crops, and the contamination of land and vegetation by spray irrigation water. (authors)

The influence of environmental conditions on lead transfer from spent gunshot to sediments and water: Other routes for Pb poisoning.

Science.gov (United States)

Binkowski, Łukasz J

2017-11-01

Lead (Pb) from spent gunshot and fishing sinkers is recognized as the main source of Pb poisoning among waterfowl. It is also suspected to directly pollute water and sediments, but no appropriate, comprehensive evaluation of this issue has so far been carried out. An experiment on Pb pellets in microcosms (n = 160) with two sediment types (mud and gravel), three water pH values (4, 7 and 9) and two wind levels (wind and windless simulation) was therefore run. Substantial differences in Pb transfer (measured with ICP-OES) between sediment types and pH levels of water were observed. Simulated wind conditions were a significant factor only for some variables and circumstances. The strongest Pb deposit to water and sediments occurred in mud microcosms with water of pH value of 4. Median pellet erosion during the experiment differed little between sediment types. The experiment revealed that Pb transfer from spent gunshot to the environment occurs only in specific environmental conditions. Copyright © 2017 Elsevier Ltd. All rights reserved.

Conditional cash transfer programs and the health and nutrition of Latin American children

Directory of Open Access Journals (Sweden)

Sofia Segura-Pérez

Full Text Available ABSTRACT Objective To 1 describe the benefits, conditions, coverage, funding, goals, governance, and structure of well-established conditional cash transfer programs (CCTs in Latin America and 2 identify their health and nutritional impacts among children under 5 years old. Methods A realist review was conducted. CCTs were included if they met the following inclusion criteria: 1 current national-level program; 2 coverage of at least 50% of the target population; 3 continuous operation at scale for 10+ years; 4 clear description of structure, funding sources, and governance; 5 both health/nutrition- and education-related conditions for participation; and 6 available impact evaluation studies with health, development, and/or nutrition indicators among children under 5 years old. Three CCTs (one each in Brazil, Colombia, and Mexico met the criteria. Results There was consistent evidence that the three CCTs selected for review had positive impacts on child health and nutrition outcomes in their respective countries. In all three countries, the programs were scaled up and positive impacts were documented relatively quickly. All three programs had strong political support and clear and transparent governance structures, including accountability and social participation mechanisms, which might explain their success and sustainability. Conclusions CCTs in Latin America have had a positive impact on child health and nutrition outcomes among the poorest families. A key challenge for the future is to reform these programs to help families move out of not only extreme poverty but all poverty in order to lead healthy and productive lives, as called for in the post-2105 Sustainable Development Goals.

Cumulants of heat transfer across nonlinear quantum systems

Science.gov (United States)

Li, Huanan; Agarwalla, Bijay Kumar; Li, Baowen; Wang, Jian-Sheng

2013-12-01

We consider thermal conduction across a general nonlinear phononic junction. Based on two-time observation protocol and the nonequilibrium Green's function method, heat transfer in steady-state regimes is studied, and practical formulas for the calculation of the cumulant generating function are obtained. As an application, the general formalism is used to study anharmonic effects on fluctuation of steady-state heat transfer across a single-site junction with a quartic nonlinear on-site pinning potential. An explicit nonlinear modification to the cumulant generating function exact up to the first order is given, in which the Gallavotti-Cohen fluctuation symmetry is found still valid. Numerically a self-consistent procedure is introduced, which works well for strong nonlinearity.

Optimization of the southern electrophoretic transfer method

International Nuclear Information System (INIS)

Allison, M.A.; Fujimura, R.K.

1987-01-01

The technique of separating DNA fragments using agarose gel electrophoresis is essential in the analysis of nucleic acids. Further, after the method of transferring specific DNA fragments from those agarose gels to cellulose nitrate membranes was developed in 1975, a method was developed to transfer DNA, RNA, protein and ribonucleoprotein particles from various gels onto diazobenzyloxymethyl (DBM) paper using electrophoresis as well. This paper describes the optimum conditions for quantitative electrophoretic transfer of DNA onto nylon membranes. This method exemplifies the ability to hybridize the membrane more than once with specific RNA probes by providing sufficient retention of the DNA. Furthermore, the intrinsic properties of the nylon membrane allow for an increase in the efficiency and resolution of transfer while using somewhat harsh alkaline conditions. The use of alkaline conditions is of critical importance since we can now denature the DNA during transfer and thus only a short pre-treatment in acid is required for depurination. 9 refs., 7 figs

Experimental Evidence on Transfer Pricing

Directory of Open Access Journals (Sweden)

Tran Quoc H.

2016-06-01

Full Text Available We use incentivized economics experiments to test both the point predictions and comparative static predictions of optimal transfer pricing models, comparing behavior under varying conditions, including wholly versus partially-owned subsidiaries and different tariff and tax rates. As predicted, we find that transfer prices are responsive to relative tax and tariff rates as well as ownership proportions. Additionally, we examine convergence and learning in this setting. While individuals do not choose optimal transfer prices, their choices converge to optimal levels with experience. This paper thus makes two important contributions. First, by comparing behavior with theoretical predictions it provides evidence of whether (and when individuals set transfer prices optimally. Second, by comparing behavior under conditions of full and partial ownership it provides evidence on the impact of policy interventions (like regulating ownership proportions by MNEs on tax revenues.

Assessing the ability of mechanistic volatilization models to simulate soil surface conditions: a study with the Volt'Air model.

Science.gov (United States)

Garcia, L; Bedos, C; Génermont, S; Braud, I; Cellier, P

2011-09-01

Ammonia and pesticide volatilization in the field is a surface phenomenon involving physical and chemical processes that depend on the soil surface temperature and water content. The water transfer, heat transfer and energy budget sub models of volatilization models are adapted from the most commonly accepted formalisms and parameterizations. They are less detailed than the dedicated models describing water and heat transfers and surface status. The aim of this work was to assess the ability of one of the available mechanistic volatilization models, Volt'Air, to accurately describe the pedo-climatic conditions of a soil surface at the required time and space resolution. The assessment involves: (i) a sensitivity analysis, (ii) an evaluation of Volt'Air outputs in the light of outputs from a reference Soil-Vegetation-Atmosphere Transfer model (SiSPAT) and three experimental datasets, and (iii) the study of three tests based on modifications of SiSPAT to establish the potential impact of the simplifying assumptions used in Volt'Air. The analysis confirmed that a 5 mm surface layer was well suited, and that Volt'Air surface temperature correlated well with the experimental measurements as well as with SiSPAT outputs. In terms of liquid water transfers, Volt'Air was overall consistent with SiSPAT, with discrepancies only during major rainfall events and dry weather conditions. The tests enabled us to identify the main source of the discrepancies between Volt'Air and SiSPAT: the lack of gaseous water transfer description in Volt'Air. They also helped to explain why neither Volt'Air nor SiSPAT was able to represent lower values of surface water content: current classical water retention and hydraulic conductivity models are not yet adapted to cases of very dry conditions. Given the outcomes of this study, we discuss to what extent the volatilization models can be improved and the questions they pose for current research in water transfer modeling and parameterization

Modifications to nuclear power plants. Safety guide

International Nuclear Information System (INIS)

2004-01-01

control and that the modified configuration conforms to the approved basis for granting a nuclear power plant operating licence. The main purpose of the recommendations concerning changes of management is to give general guidance on performing those changes in such a way that the safety of the plant is not compromised. This Safety Guide deals with the intended modification of structures, systems and components, operational limits and conditions, procedures and software, and the management systems and tools for the operation of a nuclear power plant. The recommendations made cover the whole modification process, from conception to completion. The justification for undertaking modifications is outside the scope of this Safety Guide. The modification and/or refurbishment of nuclear power plants for the purpose of extending the design lifetime could necessitate many major design modifications and special re-evaluation of plant safety (see Ref. [2]), and is therefore outside the scope of this publication. Section 2 gives guidance on general methods for modifications that could be implemented at nuclear power plants. Section 3 identifies the roles and responsibilities of various organizations involved in the modification process. Sections 4 and 5 give guidance on the different types of modification and their assessment in respect of safety aspects, and Section 4 provides guidelines on subsequent categorization. Section 6 deals with aspects of temporary modifications. Sections 7 and 8 give guidance on implementation of different types of modifications. Sections 9, 10 and 11 give basic recommendations on quality assurance, training and management of documentation. Comprehensive guidance on these matters can be found in the appropriate Safety Guides

Modifications to nuclear power plants. Safety guide

International Nuclear Information System (INIS)

2007-01-01

control and that the modified configuration conforms to the approved basis for granting a nuclear power plant operating licence. The main purpose of the recommendations concerning changes of management is to give general guidance on performing those changes in such a way that the safety of the plant is not compromised. This Safety Guide deals with the intended modification of structures, systems and components, operational limits and conditions, procedures and software, and the management systems and tools for the operation of a nuclear power plant. The recommendations made cover the whole modification process, from conception to completion. The justification for undertaking modifications is outside the scope of this Safety Guide. The modification and/or refurbishment of nuclear power plants for the purpose of extending the design lifetime could necessitate many major design modifications and special re-evaluation of plant safety, and is therefore outside the scope of this publication. Section 2 gives guidance on general methods for modifications that could be implemented at nuclear power plants. Section 3 identifies the roles and responsibilities of various organizations involved in the modification process. Sections 4 and 5 give guidance on the different types of modification and their assessment in respect of safety aspects, and Section 4 provides guidelines on subsequent categorization. Section 6 deals with aspects of temporary modifications. Sections 7 and 8 give guidance on implementation of different types of modifications. Sections 9, 10 and 11 give basic recommendations on quality assurance, training and management of documentation. Comprehensive guidance on these matters can be found in the appropriate Safety Guides

Interface model conditions for a non-equilibrium heat transfer model for conjugate fluid/porous/solid domains

International Nuclear Information System (INIS)

Betchen, L.J.; Straatman, A.G.

2005-01-01

A mathematical and numerical model for the treatment of conjugate fluid flow and heat transfer problems in domains containing pure fluid, porous, and pure solid regions has been developed. The model is general and physically reasoned, and allows for local thermal non-equilibrium in the porous region. The model is developed for implementation on a simple collocated finite volume grid. Of particular novelty are the conditions implemented at the interfaces between porous regions, and those containing a pure solid or pure fluid. The model is validated by simulation of a three-dimensional porous plug problem for which experimental results are available. (author)

Shielding modification and safety review on the nuclear ship 'Mutsu'

International Nuclear Information System (INIS)

Osanai, Masao

1978-01-01

The Japan Atomic Energy Commission (JAEC) called on the Japan Nuclear Ship Development Agency (JNSDA) for shielding modification and safety review on the nuclear ship ''Mutsu'', and JNSDA has conducted the research and development (R and D) to meet the request of JAEC for the above two items. Concerning the shield modification, the following matters are described: the study on the cause of radiation leakage which was concluded to the fast neutron streaming, the conceptual design for this modification, the mock up experiment for shielding utilizing JRR-4, the basic design following on the conceptual design, including the detailed drawings of the modified construction and the shielding analysis using RADHEAT-V3 code, and the relating experiments such as the heat transfer test of the primary shielding structure and the test of strength in stranding. As for the safety review, the survey of the troubles and the technical problems having been experienced in the light water reactor plants of land use, for example, fuel integrity, stress corrosion cracking and the leakage of steam generator tubes, the revision of the design so as to adapt to current safety standards and regulations, for example, in-service inspection, the setting of additional leak detectors in the primary cooling system, the modification of emergeney filters, etc., and the review of the design and construction corresponding to recent R and D works, such as re-evaluation of the core design, cooling capability of natural circulation, thermal stress analysis of main pipings, and the evaluation of ECCS performance are presented . (Nakai, Y.)

Modification of the activity of lymphocytes by xenotransplantation of thyroid gland tissue and by the transfer factor of immune reactivity in the case of radiation-induced hypothyrosis

International Nuclear Information System (INIS)

Goleva, O.G.; Paster, Yi.P.; Lyubchenko, T.A.; Kholodna, L.S.; Paster, Je.U.; Donyich, S.F.; Grodzins'kij, D.M.

1999-01-01

Transplantation of a thyroid tissue is one of the possible methods for the curing of functional disorders of thyroid gland that appear due to the influence of insufficient environmental conditions on organism. By the micro method of lymphocyte blast transformation reaction, the functional activity of Wistar rat's splenocytes is studied. In the case of radiation-induced hypothyrosis before and after xenotransplantation of the organic cell culture of thyroid gland of newborn pigs, the opportunities for correction of immunological disorders with the help of transfer factor preparations are investigated. The transfer factor is a low-molecular weight leukocyte extract (≤ 10kD) with immuno modulating activities. The reducing of self and PHA-stimulated proliferation of rat's splenocytes with [J131]-induced hypothyrosis is found. Bovine and human transfer factor preparations activate the proliferation of splenocytes from animals with hypothyrosis and animals with xenotransplantation

Mercury transfer in a subtropical coastal lagoon food web (SE Gulf of California) under two contrasting climatic conditions.

Science.gov (United States)

Jara-Marini, Martin E; Soto-Jiménez, Martín F; Páez-Osuna, Federico

2012-09-01

Mercury (Hg) transference through an established and defined food web from an urbanized subtropical coastal lagoon (SE Gulf of California) was examined by using carbon and nitrogen stable isotope and Hg analyses. Concentrations of Hg in seawater (0.045-0.078 μg L(-1)), predominantly incorporated to the particulate fraction (60% of total), were lower than those found in highly contaminated coastal areas around the world (0.18-16 μg L(-1)). Although levels of Hg available for the biota (e.g., associated to the reactive and pyrite fractions; 0.11-0.15 μg g(-1)) were within of effects range-low (ER-L, 0.15-0.71 μg g(-1)) these concentrations represented from 46.6 to 67.0% of the total Hg pool that may be transferred through food web. The sequence of bio-accumulation of Hg in studied species was according with their functional guild: tertiary consumer (0.85-1.15 μg g(-1)) > secondary consumers (0.084-0.168 μg g(-1)) > primary consumers (0.014-0.160 μg g(-1)) > primary producers (0.016-0.056 μg g(-1)). Hg concentrations increased for each successive trophic position estimate through δ(15) N isotopic values, although these relationships showed differences between dry and rainy seasons (R(2) = 0.37 and R(2) = 0.39 between δ(15) N vs. Hg in organisms, respectively). We concluded that Hg is being positively transferred (biomagnification factor >1) through the studied food web probably enhanced by the favorable environmental conditions for Hg-methylation (e.g., fine sediments rich in organic matter, and environmental conditions changes of the redox, pH, and temperature) found in this urbanized coastal water, however, the study of processes methlylation and biomagnifcation of Hg need further investigations. Copyright © 2011 Wiley Periodicals, Inc.

Understanding the Transfer Deficit: Contextual Mismatch, Proactive Interference, and Working Memory Affect Toddlers' Video-Based Transfer.

Science.gov (United States)

Choi, Koeun; Kirkorian, Heather L; Pempek, Tiffany A

2017-04-17

Researchers tested the impact of contextual mismatch, proactive interference, and working memory (WM) on toddlers' transfer across contexts. Forty-two toddlers (27-34 months) completed four object-retrieval trials, requiring memory updating on Trials 2-4. Participants watched hiding events on a tablet computer. Search performance was tested using another tablet (match) or a felt board (mismatch). WM was assessed. On earlier search trials, WM predicted transfer in both conditions, and toddlers in the match condition outperformed those in the mismatch condition; however, the benefit of contextual match and WM decreased over trials. Contextual match apparently increased proactive interference on later trials. Findings are interpreted within existing accounts of the transfer deficit, and a combined account is proposed. © 2017 The Authors. Child Development © 2017 Society for Research in Child Development, Inc.

Bias modification training can alter approach bias and chocolate consumption.

Science.gov (United States)

Schumacher, Sophie E; Kemps, Eva; Tiggemann, Marika

2016-01-01

Recent evidence has demonstrated that bias modification training has potential to reduce cognitive biases for attractive targets and affect health behaviours. The present study investigated whether cognitive bias modification training could be applied to reduce approach bias for chocolate and affect subsequent chocolate consumption. A sample of 120 women (18-27 years) were randomly assigned to an approach-chocolate condition or avoid-chocolate condition, in which they were trained to approach or avoid pictorial chocolate stimuli, respectively. Training had the predicted effect on approach bias, such that participants trained to approach chocolate demonstrated an increased approach bias to chocolate stimuli whereas participants trained to avoid such stimuli showed a reduced bias. Further, participants trained to avoid chocolate ate significantly less of a chocolate muffin in a subsequent taste test than participants trained to approach chocolate. Theoretically, results provide support for the dual process model's conceptualisation of consumption as being driven by implicit processes such as approach bias. In practice, approach bias modification may be a useful component of interventions designed to curb the consumption of unhealthy foods. Copyright © 2015 Elsevier Ltd. All rights reserved.

The influence of engine speed and load on the heat transfer between gases and in-cylinder walls at fired and motored conditions of an IDI diesel engine

International Nuclear Information System (INIS)

Sanli, Ali; Ozsezen, Ahmet N.; Kilicaslan, Ibrahim; Canakci, Mustafa

2008-01-01

In this study, the heat transfer characteristics between gases and in-cylinder walls at fired and motored conditions in a diesel engine were investigated by using engine data obtained experimentally. For this investigation, a four-cylinder, indirect injection (IDI) diesel engine was tested under different engine speeds and loads. The heat transfer coefficient was calculated by using Woschni expression correlated for the IDI diesel engines, and also using Annand and Hohenberg expressions. The temperature of in-cylinder gases were determined from a basic model based on the first law of thermodynamics after measuring in-cylinder pressure experimentally. The results show that the heat transfer characteristics of the IDI diesel engine strongly depend on the engine speed and load as a function of crank angle at fired and motored conditions

The influence of engine speed and load on the heat transfer between gases and in-cylinder walls at fired and motored conditions of an IDI diesel engine

Energy Technology Data Exchange (ETDEWEB)

Sanli, Ali; Kilicaslan, Ibrahim [Department of Mechanical Education, Kocaeli University, 41380 Izmit (Turkey); Ozsezen, Ahmet N.; Canakci, Mustafa [Department of Mechanical Education, Kocaeli University, 41380 Izmit (Turkey); Alternative Fuels R and D Center, Kocaeli University, 41040 Izmit (Turkey)

2008-08-15

In this study, the heat transfer characteristics between gases and in-cylinder walls at fired and motored conditions in a diesel engine were investigated by using engine data obtained experimentally. For this investigation, a four-cylinder, indirect injection (IDI) diesel engine was tested under different engine speeds and loads. The heat transfer coefficient was calculated by using Woschni expression correlated for the IDI diesel engines, and also using Annand and Hohenberg expressions. The temperature of in-cylinder gases were determined from a basic model based on the first law of thermodynamics after measuring in-cylinder pressure experimentally. The results show that the heat transfer characteristics of the IDI diesel engine strongly depend on the engine speed and load as a function of crank angle at fired and motored conditions. (author)

The modification of equipotential surfaces in the binary systems due to the pressure of the radiation of its components

International Nuclear Information System (INIS)

Zorec, Juan; Niemela, Virpi

1980-01-01

The modification of the equipotential surfaces of a binary system is studied when the radiation pressure of both components must be taken into account. For suitable values of the radiation parameters, new forms of mass transfer or mass loss may arise [fr

Modification of cellulose with succinic anhydride in TBAA/DMSO mixed solvent under catalyst-free conditions

Science.gov (United States)

Ping-Ping Xin; Yao-Bing Huang; Chung-Yun Hse; Huai N. Cheng; Chaobo Huang; Hui. Pan

2017-01-01

Homogeneous modification of cellulose with succinic anhydride was performed using tetrabutylammonium acetate (TBAA)/dimethyl sulfoxide (DMSO) mixed solvent. The molar ratio of succinic anhydride (SA) to free hydroxyl groups in the anhydroglucose units (AGU), TBAA dosage, reaction temperature, and reaction time were investigated. The highest degree of substitution (DS)...

Use of fundamental condensation heat transfer experiments for the development of a sub-grid liquid jet condensation model

Energy Technology Data Exchange (ETDEWEB)

Buschman, Francis X., E-mail: Francis.Buschman@unnpp.gov; Aumiller, David L.

2017-02-15

Highlights: • Direct contact condensation data on liquid jets up to 1.7 MPa in pure steam and in the presence of noncondensable gas. • Identified a pressure effect on the impact of noncondensables to suppress condensation heat transfer not captured in existing data or correlations. • Pure steam data is used to develop a new correlation for condensation heat transfer on subcooled liquid jets. • Noncondensable data used to develop a modification to the renewal time estimate used in the Young and Bajorek correlation for condensation suppression in the presence of noncondensables. • A jet injection boundary condition, using a sub-grid jet condensation model, is developed for COBRA-IE which provides a more detailed estimate of the condensation rate on the liquid jet and allows the use of jet specific closure relationships. - Abstract: Condensation on liquid jets is an important phenomenon for many different facets of nuclear power plant transients and analyses such as containment spray cooling. An experimental facility constructed at the Pennsylvania State University, the High Pressure Liquid Jet Condensation Heat Transfer facility (HPLJCHT), has been used to perform steady-state condensation heat transfer experiments in which the temperature of the liquid jet is measured at different axial locations allowing the condensation rate to be determined over the jet length. Test data have been obtained in a pure steam environment and with varying concentrations of noncondensable gas. This data extends the available jet condensation data from near atmospheric pressure up to a pressure of 1.7 MPa. An empirical correlation for the liquid side condensation heat transfer coefficient has been developed based on the data obtained in pure steam. The data obtained with noncondensable gas were used to develop a correlation for the renewal time as used in the condensation suppression model developed by Young and Bajorek. This paper describes a new sub-grid liquid jet

Use of fundamental condensation heat transfer experiments for the development of a sub-grid liquid jet condensation model

International Nuclear Information System (INIS)

Buschman, Francis X.; Aumiller, David L.

2017-01-01

Highlights: • Direct contact condensation data on liquid jets up to 1.7 MPa in pure steam and in the presence of noncondensable gas. • Identified a pressure effect on the impact of noncondensables to suppress condensation heat transfer not captured in existing data or correlations. • Pure steam data is used to develop a new correlation for condensation heat transfer on subcooled liquid jets. • Noncondensable data used to develop a modification to the renewal time estimate used in the Young and Bajorek correlation for condensation suppression in the presence of noncondensables. • A jet injection boundary condition, using a sub-grid jet condensation model, is developed for COBRA-IE which provides a more detailed estimate of the condensation rate on the liquid jet and allows the use of jet specific closure relationships. - Abstract: Condensation on liquid jets is an important phenomenon for many different facets of nuclear power plant transients and analyses such as containment spray cooling. An experimental facility constructed at the Pennsylvania State University, the High Pressure Liquid Jet Condensation Heat Transfer facility (HPLJCHT), has been used to perform steady-state condensation heat transfer experiments in which the temperature of the liquid jet is measured at different axial locations allowing the condensation rate to be determined over the jet length. Test data have been obtained in a pure steam environment and with varying concentrations of noncondensable gas. This data extends the available jet condensation data from near atmospheric pressure up to a pressure of 1.7 MPa. An empirical correlation for the liquid side condensation heat transfer coefficient has been developed based on the data obtained in pure steam. The data obtained with noncondensable gas were used to develop a correlation for the renewal time as used in the condensation suppression model developed by Young and Bajorek. This paper describes a new sub-grid liquid jet

Evaluation of SO{sub 2} oxidation and fly ash filtration by an activated carbon fluidized-bed reactor: The effects of acid modification, copper addition and operating condition

Energy Technology Data Exchange (ETDEWEB)

Jui-Yeh Rau; Hui-Hsin Tseng; Bo-Chin Chiang; Ming-Yen Wey; Min-Der Lin [National Chung Hsing University, Taichung (Taiwan). Department of Environmental Engineering

2010-03-15

It is expected that the simultaneous removal of acid gases and particles from flue gas, using a single process and at the same temperature, will become an economical, and thus, desirable option. Accordingly, this study investigates the potential for the utilization of a fluidized-bed adsorbent/catalyst reactor for the simultaneous removal of SO{sub 2} and fly ash from simulated flue gas. The operating conditions for the evaluation include: (1) different pre-treatments of the adsorbent/catalyst, (2) the operating parameters of adsorption/filtration and (3) the effects of simultaneous adsorption/filtration through the fluidized-bed reactor. Based on the experimental data gathered, the Broensted acid sites were formed on the surface of activated carbon (AC) support materials after modification with nitric or sulfuric acid and it acted as anchor. This characteristic accounts for the promotion of the effects of dispersion and adsorption of the adsorbent/catalyst. Moreover, the addition of copper facilitated the oxygen transfer of SO{sub 2} to the carbon matrix. The concentration of SO{sub 2} removed by the fluidized-bed adsorbent/catalyst reactor decreased from 17.9 to 14.2 mg SO{sub 2}/g of adsorbent after exposure to a high concentration of fly ash. Therefore, an acid-pre-treatment of the adsorbent/catalyst is required to hasten the removal of SO{sub 2} in the simulated flue gas. Our result shows that the acidic groups may facilitate the adsorbent/catalyst removal of SO{sub 2} when there exist high concentrations of fly ash in the flue gas. 50 refs., 11 figs., 4 tabs.

Inhibition of crossed-beam energy transfer induced by expansion-velocity fluctuations

Science.gov (United States)

Neuville, C.; Glize, K.; Loiseau, P.; Masson-Laborde, P.-E.; Debayle, A.; Casanova, M.; Baccou, C.; Labaune, C.; Depierreux, S.

2018-04-01

Crossed-beam energy transfer between three laser beams has been experimentally investigated in a flowing plasma. Time-evolution measurements of the amplification of a first beam by a second beam highlighted the inhibition of energy transfer by hydrodynamic modifications of the plasma in the crossing volume due to the propagation of a third beam. According to 3D simulations and an analytical model, it appears that the long-wavelength expansion-velocity fluctuations produced by the propagation of the third beam in the crossing volume are responsible for this mitigation of energy transfer. This effect could be a cause of the over-estimation of the amount of the transferred energy in indirect-drive inertial confinement fusion experiments. Besides, tuning such long-wavelength fluctuations could be a way to completely inhibit CBET at the laser entrance holes of hohlraums.

The experimental modification of sonorous breathing.

OpenAIRE

Josephson, S C; Rosen, R C

1980-01-01

Loud snoring is a noxious habit and potential personal health risk. We are reporting the first experimental study of simple behavioral techniques for the modification of chronic snoring. Twenty-four volunteers participated in a repeated measures, randomized group design over 2 weeks of intervention and one-month follow-up. Treatment groups included a contingent-awakening and breathing retraining (self-control) condition. Both treatment groups were compared to a no-treatment control. Despite c...

Use of Behavior Modification with L. D. Students.

Science.gov (United States)

Belcastro, Frank P.

Reviewed was research on the application of operant conditioning techniques to the modification of the classroom behavior of learning disabled students. The methodology and results of the studies were examined and each study summarized. It was concluded that there was little common interpretation of the term "learning disabilities" and that all of…

Radioactivity transfer to animal products

International Nuclear Information System (INIS)

Coughtrey, P.J.

1990-01-01

Information on the behaviour of strontium, caesium, ruthenium, plutonium and americium in a range of domestic animals is reviewed to form a basis for the specification of time-dependent mathematical models describing uptake, distribution and retention in various domestic animals. Transfer factors relating concentration in animal product to daily radioactivity intake are derived after 100 d continuous intake and at equilibrium. These transfer factors are compared with the available published literature and used as a basis for the derivation of feedingstuff conversion factors relating limiting concentrations in animal feedingstuffs to limiting concentrations in human foodstuffs for application to animals receiving commercial feedingstuffs after a nuclear accident. Recommended transfer factors for animal products in conditions of continuous discharge and models for application to field conditions after a nuclear accident are also presented. Transfer of caesium to animal products is more effective than that for the other elements considered here. Transfer to meat of lamb, fattening pig, and chickens is generally more effective than that for other animals and other products

Electron Transfer and Collision Induced Dissociation of Non-Derivatized and Derivatized Desmosine and Isodesmosine

NARCIS (Netherlands)

Ongay, Sara; Hermans, Jos; Bruins, Andries P.; Nieuwendijk, Adrianus M. C. H.; Overkleeft, Hermen; Bischoff, Rainer

Electron transfer dissociation (ETD) has attracted increasing interest due to its complementarity to collision-induced dissociation (CID). ETD allows the direct localization of labile post-translational modifications, which is of main interest in proteomics where differences and similarities between

An Undergraduate Chemistry Laboratory: Synthesis of Well-Defined Polymers by Low-Catalyst-Concentration ATRP and Postpolymerization Modification to Fluorescent Materials

Science.gov (United States)

Tsarevsky, Nicolay V.; Woodruf, Shannon R.; Wisian-Neilson, Patty J.

2016-01-01

A two-session experiment is designed to introduce undergraduate students to concepts in catalysis, transition metal complexes, polymer synthesis, and postpolymerization modifications. In the first session, students synthesize poly(glycidyl methacrylate) via low-catalyst-concentration atom transfer radical polymerization (ATRP). The…

CFD analysis of flow and heat transfer in Canadian supercritical water reactor bundle

International Nuclear Information System (INIS)

Podila, K.; Rao, Y.F.

2015-01-01

Highlights: • Flow and heat transfer in SCWR fuel bundle design by AECL is studied using CFD. • Bare-rod bundle geometry is tested at 23.5, 25 and 28 MPa using STAR-CCM+ code. • SST k–ω low-Re model was used to study occurrence of heat transfer deterioration. - Abstract: Within the Gen-IV International Forum, AECL is leading the effort in developing a conceptual design for the Canadian SCWR. AECL proposed a new fuel bundle design with two rings of fuel elements placed between central flow tube and the pressure tube. In line with the scope of the conceptual design, the objective of the present CFD work is to aid in developing a bundle heat transfer correlation for the Canadian SCWR fuel bundle design. This paper presents results from an ongoing effort in determining the conditions favorable for occurrence of HTD in the supercritical bundle flows. In the current investigation, bare-rod bundle geometry was tested for the proposed fuel bundle design at 23.5, 25 and 28 MPa using STAR-CCM+ CFD code. Taking advantage of the design symmetry of the fuel bundle, only 1/32 of the computational domain was simulated. The low-Reynolds number modification of SST k–ω turbulence model along with y + < 1 was used in the simulations. For lower mass flow simulations, the increase of inlet temperature and operational pressure was found effective in reducing the occurrence of HTD. For higher mass flow simulations, normal heat transfer behaviour was observed except for the lower pressure range (23.5 MPa)

Application of intensified heat transfer for the retrofit of heat exchanger network

International Nuclear Information System (INIS)

Wang, Yufei; Pan, Ming; Bulatov, Igor; Smith, Robin; Kim, Jin-Kuk

2012-01-01

Highlights: → Novel design approach for the retrofit of HEN based on intensified heat transfer. → Development of a mathematical model to evaluate shell-and-tube heat exchanger performances. → Identification of the most appropriate heat exchangers requiring heat transfer enhancements in the heat exchanger network. -- Abstract: A number of design methods have been proposed for the retrofit of heat exchanger networks (HEN) during the last three decades. Although considerable potential for energy savings can be identified from conventional retrofit approaches, the proposed solutions have rarely been adopted in practice, due to significant topology modifications required and resulting engineering complexities during implementation. The intensification of heat transfer for conventional shell-and-tube heat exchangers can eliminate the difficulties of implementing retrofit in HEN which are commonly restricted by topology, safety and maintenance constraints, and includes high capital costs for replacing equipment and pipelines. This paper presents a novel design approach to solve HEN retrofit problems based on heat transfer enhancement. A mathematical model has been developed to evaluate shell-and-tube heat exchanger performances, with which heat-transfer coefficients and pressure drops for both fluids in tube and shell sides are obtained. The developed models have been compared with the Bell-Delaware, simplified Tinker and Wills-Johnston methods and tested with the HTRI (registered) and HEXTRAN (registered) software packages. This demonstrates that the new model is much simpler but can give reliable results in most cases. For the debottlenecking of HEN, four heuristic rules are proposed to identify the most appropriate heat exchangers requiring heat transfer enhancements in the HEN. The application of this new design approach allows a significant improvement in energy recovery without fundamental structural modifications to the network.

Quasilocal conservation laws in XXZ spin-1/2 chains: Open, periodic and twisted boundary conditions

Directory of Open Access Journals (Sweden)

Tomaž Prosen

2014-09-01

Full Text Available A continuous family of quasilocal exact conservation laws is constructed in the anisotropic Heisenberg (XXZ spin-1/2 chain for periodic (or twisted boundary conditions and for a set of commensurate anisotropies densely covering the entire easy plane interaction regime. All local conserved operators follow from the standard (Hermitian transfer operator in fundamental representation (with auxiliary spin s=1/2, and are all even with respect to a spin flip operation. However, the quasilocal family is generated by differentiation of a non-Hermitian highest weight transfer operator with respect to a complex auxiliary spin representation parameter s and includes also operators of odd parity. For a finite chain with open boundaries the time derivatives of quasilocal operators are not strictly vanishing but result in operators localized near the boundaries of the chain. We show that a simple modification of the non-Hermitian transfer operator results in exactly conserved, but still quasilocal operators for periodic or generally twisted boundary conditions. As an application, we demonstrate that implementing the new exactly conserved operator family for estimating the high-temperature spin Drude weight results, in the thermodynamic limit, in exactly the same lower bound as for almost conserved family and open boundaries. Under the assumption that the bound is saturating (suggested by agreement with previous thermodynamic Bethe ansatz calculations we propose a simple explicit construction of infinite time averages of local operators such as the spin current.

N-terminal modifications of cellular proteins: The enzymes involved, their substrate specificities and biological effects

Science.gov (United States)

Varland, Sylvia; Osberg, Camilla; Arnesen, Thomas

2015-01-01

The vast majority of eukaryotic proteins are N-terminally modified by one or more processing enzymes. Enzymes acting on the very first amino acid of a polypeptide include different peptidases, transferases, and ligases. Methionine aminopeptidases excise the initiator methionine leaving the nascent polypeptide with a newly exposed amino acid that may be further modified. N-terminal acetyl-, methyl-, myristoyl-, and palmitoyltransferases may attach an acetyl, methyl, myristoyl, or palmitoyl group, respectively, to the α-amino group of the target protein N-terminus. With the action of ubiquitin ligases, one or several ubiquitin molecules are transferred, and hence, constitute the N-terminal modification. Modifications at protein N-termini represent an important contribution to proteomic diversity and complexity, and are essential for protein regulation and cellular signaling. Consequently, dysregulation of the N-terminal modifying enzymes is implicated in human diseases. We here review the different protein N-terminal modifications occurring co- or post-translationally with emphasis on the responsible enzymes and their substrate specificities. PMID:25914051

Transfer of skill engendered by complex task training under conditions of variable priority.

Science.gov (United States)

Boot, Walter R; Basak, Chandramallika; Erickson, Kirk I; Neider, Mark; Simons, Daniel J; Fabiani, Monica; Gratton, Gabriele; Voss, Michelle W; Prakash, Ruchika; Lee, HyunKyu; Low, Kathy A; Kramer, Arthur F

2010-11-01

We explored the theoretical underpinnings of a commonly used training strategy by examining issues of training and transfer of skill in the context of a complex video game (Space Fortress, Donchin, 1989). Participants trained using one of two training regimens: Full Emphasis Training (FET) or Variable Priority Training (VPT). Transfer of training was assessed with a large battery of cognitive and psychomotor tasks ranging from basic laboratory paradigms measuring reasoning, memory, and attention to complex real-world simulations. Consistent with previous studies, VPT accelerated learning and maximized task mastery. However, the hypothesis that VPT would result in broader transfer of training received limited support. Rather, transfer was most evident in tasks that were most similar to the Space Fortress game itself. Results are discussed in terms of potential limitations of the VPT approach. Copyright © 2010 Elsevier B.V. All rights reserved.

Effects of Conditional Cash Transfers (CCT in Anti-Poverty Programs. An Empirical Approach with Panel Data for the Mexican Case of PROSPERA-Oportunidades (2002–2012

Directory of Open Access Journals (Sweden)

Odra Angélica Saucedo Delgado

2018-05-01

Full Text Available Conditional Cash Transfer Programs (CCT have been implemented in México and Latin America since the late 1990’s. This type of program focuses on providing social government services by way of direct cash transfers to poor families that are often conditioned to the use of public education and health services. Despite the apparent short-term success of these CCT programs in the Latin American context, there still is much debate about whether CCT programs are effective in alleviating poverty. This paper analyzes the effectiveness of conditional cash transfer programs as a long-term incentive in the use of public services—health and education—among beneficiary families of PROSPERA-Oportunidades in Mexico. The Average Effect of Treatment on the Treated (ATT for the time period 2002–2012 is estimated based on data from the Mexican Family Life Survey (MxFLS using Propensity Score Matching (PSM. The results show that the program’s impact on the use of preventive health and education services by poor families cannot be sustained in the long-term, which puts in doubt the effectiveness of this social protection intervention program in combating poverty in Mexico.

Acidic deposition: State of science and technology. Report 24. Visibility: Existing and historical conditions - causes and effects. Final report

International Nuclear Information System (INIS)

Trijonis, J.C.; Malm, W.C.; Pitchford, M.; White, W.H.; Charlson, R.

1990-10-01

One of the important effects associated with acid precipitation related pollutants is interference with radiation transfer (light transmission) in the atmosphere. An obvious result of such interference is visibility degradation--the impairment of atmospheric clarity or of the ability to perceive form, texture, and color. Climate modification constitutes another, somewhat less obvious, result. The purpose of the NAPAP State of Science/Technology report is to summarize current knowledge regarding these radiation transfer effects. Although the report focuses mainly on visibility issues, it does encompass the emerging field of climate modification. The links between the acid rain problem and radiation transfer effects, although indirect, are quite strong. The principal link is through sulfur dioxide emissions and sulfate aerosols. A secondary link occurs through nitrogen oxide emissions

System for measuring the effect of fouling and corrosion on heat transfer under simulated OTEC conditions. [HTAU and LABTTF codes

Energy Technology Data Exchange (ETDEWEB)

Fetkovich, J.G.

1976-12-01

A complete system designed to measure, with high precision, changes in heat transfer rates due to fouling and corrosion of simulated heat exchanger tubes, at sea and under OTEC conditions is described. All aspects of the system are described in detail, including theory, mechanical design, electronics design, assembly procedures, test and calibration, operating procedures, laboratory results, field results, and data analysis programs.

CFD heat transfer simulation of the human upper respiratory tract for oronasal breathing condition

Directory of Open Access Journals (Sweden)

Kambiz Farahmand

2012-01-01

Full Text Available Injuries due to inhalation of hot gas are commonly encountered when dealing with fire and combustible material, which is harmful and threatens human life. In the literature, various studies have been conducted to investigate heat and mass transfer characteristics in the human respiratory tract (HRT. This study focuses on assessing the injury taking place in the upper human respiratory tract and identifying acute tissue damage, based on level of exposure. A three-dimensional heat transfer simulation is performed using Computational Fluid Dynamics (CFD software to study the temperature profile through the upper HRT consisting of the nasal cavity, oral cavity, trachea, and the first two generations of bronchi. The model developed is for the simultaneous oronasal breathing during the inspiration phase with a high volumetric flow rate of 90 liters/minute and the inspired air temperature of 100 degrees Celsius. The geometric model depicting the upper HRT is generated based on the data available and literature cited. The results of the simulation give the temperature distribution along the center and the surface tissue of the respiratory tract. This temperature distribution will help to assess the level of damage induced in the upper respiratory tract and appropriate treatment for the damage. A comparison of nasal breathing, oral breathing, and oronasal breathing is performed. Temperature distribution can be utilized in the design of the respirator systems where inlet temperature is regulated favoring the human body conditions.

Batch culture of Azotobacter vinelandii under oxygen limitation conditionS

Energy Technology Data Exchange (ETDEWEB)

Camacho Rubio, F.; Martinez Nieto, L.; Fernandez Serrano, M.; Jimenez Moleon, M.C. [Departamento de Ingenieria Quimica, Universidad de Granada, Granada (Spain)

1996-12-01

The batch culture of Azotobacter vinealandii on glucose under nitrogen-fixing conditions, seeking oxygen limitation conditions, has been studied in order to use it as a Biological Test System for the experimental study of oxygen transfer enhancement methods in aerobic fermenters. overall kinetic parameters for exponential growth and for linear growth (under oxygen limitation) have been determined. It was noted an appreciable influence of the oxygen transfer rate on glucose and oxygen uptake, which seems to be due to alginate production, excreted as a nitrogenase protection mechanisms. (Author) 12 refs.

Appetitive Pavlovian-instrumental Transfer: A review.

Science.gov (United States)

Cartoni, Emilio; Balleine, Bernard; Baldassarre, Gianluca

2016-12-01

Reward-related cues are an important part of our daily life as they often influence and guide our actions. This paper reviews one of the experimental paradigms used to study the effects of cues, the Pavlovian to Instrumental Transfer paradigm. In this paradigm, cues associated with rewards through Pavlovian conditioning alter motivation and choice of instrumental actions. The first transfer experiments date back to the 1940s, but only in the last decade has it been fully recognised that there are two types of transfer, specific and general. This paper presents a systematic review of both the neural substrates and the behavioral factors affecting both types of transfer. It also examines the recent application of the paradigm to study the effect of cues on human participants, both in normal and pathological conditions, and the interactions of transfer with drugs of abuse. Finally, the paper analyses the theoretical aspects of transfer to build an overall picture of the phenomenon, from early theories to recent hierarchical accounts. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Cattaneo-Christov on heat and mass transfer of unsteady Eyring Powell dusty nanofluid over sheet with heat and mass flux conditions

Directory of Open Access Journals (Sweden)

Mamatha S. Upadhay

2017-01-01

Full Text Available Heat and mass flux conditions on magnetohydrodynamic unsteady Eyring-Powell dusty nanofluid over a sheet is addressed. The combined effect of Brownian motion and thermophoresis in nanofluid modeling are retained. The Cattaneo-Christov heat flux model is imposed. A set of similarity variables are utilized to form ordinary differential system from the prevailing partial differential equations. The problem of ordinary differential system (ODS is analyzed numerically through Runge-Kutta based shooting method. Graphical results of pertinent parameters on the velocity, temperature and nanoparticle concentration are studied. Skin friction coefficient, local Nusselt and Sherwood number are also addressed with help of graphs and also validated the present solutions with already existing solutions in the form of table. It is found that the thermal relaxation parameter improves the heat transfer rate and minimizes the mass transfer rate. The heat transfer rate is higher in prescribed heat flux (PHF case when compared with prescribed wall temperature (PWT case.

A model technology transfer program for independent operators: Kansas Technology Transfer Model (KTTM)

Energy Technology Data Exchange (ETDEWEB)

Schoeling, L.G.

1993-09-01

This report describes the development and testing of the Kansas Technology Transfer Model (KTTM) which is to be utilized as a regional model for the development of other technology transfer programs for independent operators throughout oil-producing regions in the US. It describes the linkage of the regional model with a proposed national technology transfer plan, an evaluation technique for improving and assessing the model, and the methodology which makes it adaptable on a regional basis. The report also describes management concepts helpful in managing a technology transfer program. The original Tertiary Oil Recovery Project (TORP) activities, upon which the KTTM is based, were developed and tested for Kansas and have proved to be effective in assisting independent operators in utilizing technology. Through joint activities of TORP and the Kansas Geological Survey (KGS), the KTTM was developed and documented for application in other oil-producing regions. During the course of developing this model, twelve documents describing the implementation of the KTTM were developed as deliverables to DOE. These include: (1) a problem identification (PI) manual describing the format and results of six PI workshops conducted in different areas of Kansas, (2) three technology workshop participant manuals on advanced waterflooding, reservoir description, and personal computer applications, (3) three technology workshop instructor manuals which provides instructor material for all three workshops, (4) three technologies were documented as demonstration projects which included reservoir management, permeability modification, and utilization of a liquid-level acoustic measuring device, (5) a bibliography of all literature utilized in the documents, and (6) a document which describes the KTTM.

Structural Modification of Organic Thin-Film Transistors for Photosensor Application

Science.gov (United States)

Jeong, Hyeon Seok; Bae, Jin-Hyuk; Lee, Hyeonju; Ndikumana, Joel; Park, Jaehoon

2018-05-01

We investigated the light response characteristics of bottom-gate/top-contact organic TFTs fabricated using pentacene and polystyrene as an organic semiconductor and a polymeric insulator, respectively. The pentacene TFT with overlaps (50 μm) between the source and gate electrodes as well as between the drain and gate electrodes exhibited negligible hysteresis in its transfer characteristics upon reversal of the gate voltage sweep direction. When the TFTs were structurally modified to produce an underlap structure between the source and gate electrodes, clockwise hysteresis and a drain-current decrease were observed, which were further augmented by increasing the gate underlap (from 30 μm to 50 μm and 70 μm). Herein, these results are explained in terms of space charge formation and accumulation capacitance reduction. Importantly, we found that space charges formed under the source electrode contributed to the drain currents via light irradiation through the underlap region. Under constant bias conditions, the TFTs with gate underlap structures thus exhibited on-state drain current changes in response to light signals. In our study, an optimal photosensitivity exceeding 11 was achieved by the TFT with a 30 μm gate underlap. Consequently, we suggest that gate underlap structure modification is a viable means of implementing light responsiveness in organic TFTs.

Evaluation of proposed panel closure modifications at WIPP

Energy Technology Data Exchange (ETDEWEB)

Allen, Lawrence E.; Silva, Matthew K.; Channell, James K.; Abel, John F.; Morgan, Dudley R.

2001-12-31

A key component in the design of the WIPP repository is the installation of concrete structures as panel seals in the intake and exhaust drifts after a panel has been filled with waste containers. As noted in the EPA final rule, the panel seal closure system is intended to block brine flow between the waste panels at the WIPP. On April 17, 2001, the DOE proposed seven modifications to the EPA concerning the design of the panel closure system. EPA approval of these modifications is necessary since the details of the panel design are specified in EPA’s final rule as a condition for WIPP certification. However, the EPA has not determined whether a rulemaking would be required for these proposed design modifications. On September 4, 2001, the DOE withdrew the request, noting that it would be resubmitted on a future date. The Environmental Evaluation Group (EEG) contracted with two engineers, Dr. John Abel and Dr. Rusty Morgan, to evaluate the proposed modifications. The EEG has accepted the conclusions and recommendations from these two experts: 1) replacement of Salado Mass Concrete with a generic salt-based concrete; 2) replacement of the explosion wall with a construction wall; 3) replacement of freshwater grouting with salt-based grouting; 4) option to allow surface or underground mixing; and 5) option to allow up to one year for completion of closure. The proposed modification to allow local carbonate river rock as aggregate is acceptable pending demonstration that no problems will exist in the resulting concrete. The proposed modification to give the contractor discretion in removal of steel forms is not supported. Instead, several recommendations are made to specifically reduce the number of forms left, thereby reducing potential migration pathways.

Heat transfer and pressure drop of a gasket-sealed plate heat exchanger depending on operating conditions across hot and cold sides

Energy Technology Data Exchange (ETDEWEB)

Ahn, Joon [Kookmin University, Seoul (Korea, Republic of); Kim, Hyouck Ju [Korea Institute of Energy Research, Daejeon (Korea, Republic of)

2016-05-15

In a gas engine based cogeneration system, heat may be recovered from two parts: Jacket water and exhaust gas. The heat from the jacket water is often recovered using a plate-type heat exchanger, and is used for room heating and/or hot water supply applications. Depending on the operating conditions of an engine and heat recovery system, there may be an imbalance in the flow rate and supply pressure between the engine side and the heat-recovery side of the heat exchanger. This imbalance causes deformation of the plate, which affects heat transfer and pressure drop characteristics. In the present study, the heat transfer and pressure drop inside a heat exchanger were investigated under varying hot-side and cold-side operating conditions. Thermal efficiency of the plate heat exchanger decreases up to 30% with an operating engine load of 50%. A correction factor for the pressure drop correlation is proposed to account for the deformation caused by an imbalance between the two sides of a heat exchanger.

Elaboration and modification of the waste zoning plan in basic nuclear installations. ASN Guide Nr 23, Release of the 2016/08/30

International Nuclear Information System (INIS)

2016-01-01

After having recalled the relevant regulatory texts and guides, this guide aims at detailing conditions of elaboration and of modification of the waste zoning plan which is defined in one of these texts, and applies requirements and recommendations of others of them. It first recalls the general doctrine of waste management in basic nuclear installations. It describes how the waste zoning plan and the reference waste zoning map are elaborated and justified, how the relevancy of this plan and this map are confirmed through radiological controls and based on general operation rules and periodic assessments. It also describes how contamination transfers and material activation are prevented, and discusses waste radiological controls to be performed. The next part addressed waste zoning and ways of management for wastes coming from conventional waste areas, and from areas of possible production of nuclear wastes. Issues of waste zoning downgrading or reclassification are then addressed by distinguishing temporary and definitive modifications (in one way or the other). Some peculiar cases are addressed: delimitation of waste zoning at the level of equipments, conventional processing of some wastes, radioactive waste warehousing, outdoor areas of possible production of nuclear wastes

Thermal biology mediates responses of amphibians and reptiles to habitat modification.

Science.gov (United States)

Nowakowski, A Justin; Watling, James I; Thompson, Michelle E; Brusch, George A; Catenazzi, Alessandro; Whitfield, Steven M; Kurz, David J; Suárez-Mayorga, Ángela; Aponte-Gutiérrez, Andrés; Donnelly, Maureen A; Todd, Brian D

2018-03-01

Human activities often replace native forests with warmer, modified habitats that represent novel thermal environments for biodiversity. Reducing biodiversity loss hinges upon identifying which species are most sensitive to the environmental conditions that result from habitat modification. Drawing on case studies and a meta-analysis, we examined whether observed and modelled thermal traits, including heat tolerances, variation in body temperatures, and evaporative water loss, explained variation in sensitivity of ectotherms to habitat modification. Low heat tolerances of lizards and amphibians and high evaporative water loss of amphibians were associated with increased sensitivity to habitat modification, often explaining more variation than non-thermal traits. Heat tolerances alone explained 24-66% (mean = 38%) of the variation in species responses, and these trends were largely consistent across geographic locations and spatial scales. As habitat modification alters local microclimates, the thermal biology of species will likely play a key role in the reassembly of terrestrial communities. © 2018 John Wiley & Sons Ltd/CNRS.

Successful design and application of SNCR parallel to combustion modification

Energy Technology Data Exchange (ETDEWEB)

Zhao, Dongxian; Tang, Leping; Shao, Xiaozhen; Meng, Derun; Li, Hongjian [Tongfang Environment CO., LTD., Beijing (China); Zhou, Wei; Xu, Guang [GE Energy, Anaheim, CA (United States)

2013-07-01

Various De-NOx methods have been recently adopted in China to control NOx emissions including Selective Non-Catalytic Reaction (SNCR) technology. Usually, the design of SNCR system is carried out after the combustion modification technologies, such as low NOx burner (LNB) and over fire air (OFA), have already been installed and in operation. This article discusses how to design the SNCR system parallel to the combustion modification. The SNCR process design consists of three steps: (1) boiler baseline test, (2) computational fluid dynamics simulation (CFD) facilitated design and (3) SNCR system performance predictions and optimizations. The first step is to conduct boiler baseline test to characterize the boiler operating conditions at a load range. The test data can also be used to calibrate the CFD model. The second step is to develop a three-dimensional boiler coal combustion CFD model to simulate the operation of the boilers at both baseline and post combustion modification conditions. The simulation reveals velocity, temperature and combustible distributions in the furnace. The last step is to determine the position and numbers of the injectors for SNCR reagent. The final field tests upon the project completion have shown that the average SNCR De-NOx efficiency has reached 35.1% with the maximum removal efficiency of 45% on full load. The project also couples the SNCR and SCR (Selective Catalytic Reduction) technologies. The combined removal efficiency of combustion modifications, SNCR and SCR is higher than 82%. This paper shows a successful example for retrofitting aged power-generating units with limited space.

Enzyme Technology of Peroxidases: Immobilization, Chemical and Genetic Modification

Science.gov (United States)

Longoria, Adriana; Tinoco, Raunel; Torres, Eduardo

An overview of enzyme technology applied to peroxidases is made. Immobilization on organic, inorganic, and hybrid supports; chemical modification of amino acids and heme group; and genetic modification by site-directed and random mutagenesis are included. Different strategies that were carried out to improve peroxidase performance in terms of stability, selectivity, and catalytic activity are analyzed. Immobilization of peroxidases on inorganic and organic materials enhances the tolerance of peroxidases toward the conditions normally found in many industrial processes, such as the presence of an organic solvent and high temperature. In addition, it is shown that immobilization helps to increase the Total Turnover Number at levels high enough to justify the use of a peroxidase-based biocatalyst in a synthesis process. Chemical modification of peroxidases produces modified enzymes with higher thermostability and wider substrate variability. Finally, through mutagenesis approaches, it is possible to produce modified peroxidases capable of oxidizing nonnatural substrates with high catalytic activity and affinity.

On Nonlinear Inverse Problems of Heat Transfer with Radiation Boundary Conditions: Application to Dehydration of Gypsum Plasterboards Exposed to Fire

OpenAIRE

Belmiloudi, A.; Mahé, F.

2014-01-01

International audience; The paper investigates boundary optimal controls and parameter estimates to the well-posedness nonlinear model of dehydration of thermic problems. We summarize the general formulations for the boundary control for initial-boundary value problem for nonlinear partial differential equations modeling the heat transfer and derive necessary optimality conditions, including the adjoint equation, for the optimal set of parameters minimizing objective functions J. Numerical si...

Inhibition of oxygen-glucose deprivation-induced apoptosis of human adipose-derived stem cells by genetic modification with antiapoptotic protein bcl-2.

Science.gov (United States)

Cui, Ziwei; Shen, Liangyun; Lin, Yue; Wang, Shuqin; Zheng, Dongfeng; Tan, Qian

2014-08-01

Adipose-derived stem cells (ADSCs) have become a promising tool for a wide range of cell-based therapies. However, transplanted ADSCs do not survive well under ischemic conditions. In this study we aimed to inhibit oxygen-glucose deprivation (OGD)-induced apoptosis of human ADSCs by genetic modification with antiapoptotic protein Bcl-2. After isolation and culture, the phenotypes of human ADSCs at passage 3 were analyzed by flow cytometry. Then, genetic modification of ADSCs with Bcl-2 was carried out. Bcl-2 gene transfection was verified by Western blot analysis and multipotent differentiation properties were evaluated in Bcl-2-modified ADSCs (Bcl-2-ADSCs). Apoptosis was evaluated by a TUNEL assay under ischemic conditions induced by OGD. Apoptotic nuclei were also assessed and quantified by Hoechst staining. The cultured ADSCs expressed stem cell-associated markers CD29, CD34, CD44, and CD90, but not fibroblast marker HLA-DR or hematopoietic stem cell marker CD133. The Bcl-2 gene was transferred into ADSCs efficiently, and Bcl-2-ADSCs differentiated into adipocytes, chondrocytes, and osteoblasts. In addition, Bcl-2 overexpression reduced the percentage of apoptotic Bcl-2-ADSCs by 38 % under OGD. Our results indicate that Bcl-2 overexpression through gene transfection inhibits apoptosis of ADSCs under ischemic conditions. This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews, and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies, and Experimental Studies. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

CRISPR-Cas and Restriction-Modification Act Additively against Conjugative Antibiotic Resistance Plasmid Transfer in Enterococcus faecalis

OpenAIRE

Price, Valerie J.; Huo, Wenwen; Sharifi, Ardalan; Palmer, Kelli L.

2016-01-01

ABSTRACT Enterococcus faecalis is an opportunistic pathogen and a leading cause of nosocomial infections. Conjugative pheromone-responsive plasmids are narrow-host-range mobile genetic elements (MGEs) that are rapid disseminators of antibiotic resistance in the faecalis species. Clustered regularly interspaced short palindromic repeat (CRISPR)-Cas and restriction-modification confer acquired and innate immunity, respectively, against MGE acquisition in bacteria. Most multidrug-resistant E.?fa...

Effects of Cognitive Bias Modification Training via Smartphones

Directory of Open Access Journals (Sweden)

Ranming Yang

2017-08-01

Full Text Available Background and Objectives: Negative cognitive biases have been linked to anxiety and mood problems. Accumulated data from laboratory studies show that positive and negative interpretation styles with accompanying changes in mood can be induced through cognitive bias modification (CBM paradigms. Despite the therapeutic potential of positive training effects, few studies have explored training paradigms administered via smartphones. The current study aimed to compare the effectiveness of three different types of training programmes (cognitive bias modification-attention, CBM-A; cognitive bias modification-interpretation, CBM-I; attention and interpretation modification, AIM administered via smart-phones by using a control condition (CC.Methods:Seventy-six undergraduate participants with high social anxiety (Liebowitz Social Anxiety Scale, LSAS ≥ 30 were randomly assigned to four groups: CBM-A (n = 20, CBM-I (n = 20, AIM (n = 16, and CC (n = 20.Results: The results showed that the effects of CBM training, CBM-I training, or AIM training vs. CC for attention yielded no significant differences in dot-probe attention bias scores. The CBM-I group showed significantly less threat interpretation and more benign interpretation than the CC group on interpretation bias scores.Conclusions: The present results supported the feasibility of delivering CBM-I via smartphones, but the effectiveness of CBM-A and AIM training via smartphones was limited.

Mental Health on the Go: Effects of a Gamified Attention Bias Modification Mobile Application in Trait Anxious Adults.

Science.gov (United States)

Dennis, Tracy A; O'Toole, Laura

2014-09-01

Interest in the use of mobile technology to deliver mental health services has grown in light of the economic and practical barriers to treatment. Yet, research on alternative delivery strategies that are more affordable, accessible, and engaging is in its infancy. Attention bias modification training (ABMT), has potential to reduce treatment barriers as a mobile intervention for stress and anxiety, but the degree to which ABMT can be embedded in a mobile gaming format and its potential for transfer of benefits is unknown. The present study examined effects of a gamified ABMT mobile application in highly trait anxious participants ( N = 78). A single session of the active compared to placebo training reduced subjective anxiety and observed stress reactivity. Critically, the long (45 minutes) but not short (25 minutes) active training condition reduced the core cognitive process implicated in ABMT (threat bias) as measured by an untrained, gold-standard protocol.

Engineering Task Plan for Hose-In-Hose Transfer Lines for the Interim Stabilization Program

International Nuclear Information System (INIS)

TORRES, T.D.

2000-01-01

The document is the Engineering Task Plan for the engineering, design services, planning, project integration and management support for the design, modification, installation and testing of an over ground transfer (OGT) system to support the interim stabilization of S/SX and U Tank Farms

Feed/meat transfer factor determination

International Nuclear Information System (INIS)

Hoepfner, U.

1981-01-01

The transfer of cesium from the feed to bovine meat is taken as an example to discuss natural environmental conditions and their effects on the determination of the transfer factor. Criteria for estimating the validity of experimentally determined transfer factors are given and used for a critical evaluation of significant literature data. The evaluation presented in this report is not a merely statistical evaluation of transfer data, indicating one single value as the correct one (sometimes within a certain margin), but rather scans the data available for incertainties and drawbacks of the experimental methods applied, finally stating a range of variation within which transfer factors can be considered to be correct. (orig./DG) [de

Study of heat and mass transfer phenomena in fuel assembly models under accident conditions

International Nuclear Information System (INIS)

Yefanov, A.D.; Kalyakin, C.G.; Loshchinin, V.M.; Pomet'ko, R.S.; Sergeev, V.V.; Shumsky, R.V.

1996-01-01

The majority of the material in support of the thermal - hydraulic safety of WWER core was obtained on single - assembly models containing a relatively small number of elements - heater rods. Upgrading the requirements to the reactor safety leads to the necessity for studying phenomena in channels representing the cross - sectional core dimensions and non - uniform radial power generation. Under such conditions, the contribution of natural convection can be significant in some core zones, including the occurrence of reverse flows and interchannel instability. These phenomena can have an important influence on heat transfer processes. Such influence is especially drastical under accident conditions associated with ceasing the forced circulation over the circuit. A number of urgent reactor safety problems at low operating parameters is related with the computer code verification and certification. One of the important trends in the reactor safety research is concerned with the rod bundle reflooding and verificational calculations of this phenomenon. To assess the water cooled reactor safety, the best fit computer codes are employed, which make it possible to simulate accident and transient operating conditions in a reactor installation. One of the most widely known computer codes is the RELAP5/MOD3 Code. The paper presents the comparison of the results calculated using this computer code with the test data on 4 - rod bundle quenching, which were obtained at the SSCRF-IPPE. Recently, the investigations on the steam - zirconium reaction kinetics have been performed at the SSCFR-IPPE and are being presently performed for the purpose of developing new and verifying available computer codes. (author). 3 refs, 6 figs

Heat transfer studies in waste repository design

International Nuclear Information System (INIS)

Boehm, R.F.; Chen, Y.T.; Izzeldin, A.; Kuharic, W.; Sudan, N.

1994-01-01

The main task of this project is the development of visualization methods in heat transfer through porous media. Experiments have been performed related to the determination of the wavelength that gives equality of the refractive indices of the porous material and the liquid. The work has been accomplished using the calibration setup consisting of a 2-in. long test cell filled with 2-mm diameter soda-lime glass beads. A supplemental task is an unsaturated flow experiment with heat transfer in porous media. For this work the medium of interest in quartz beads. Essentially two-dimensional flows of admitted water are able to be examined. During this quarter, the setup and calibration of the experimental instrumentation was done. Also the modification of the main experimental tank and the inflow system was carried out. Initial testing was done

Effects of nuclear elastic scattering and modifications of ion-electron equilibration power on advanced-fuel burns

International Nuclear Information System (INIS)

Galambos, J.D.

1983-01-01

The effects of Nuclear Elastic Scattering (NES) of fusion products and modifications of the ion-electron equilibration power on D-T and D-based advanced-fuel fusion plasmas are presented here. The processes causing the modifications to the equilibration power included here are: (1) depletion of low-energy electrons by Coulomb collisions with the ions; and (2) magnetic field effects on the energy transfer between the ions and the electrons. Both NES and the equilibration modifications affect the flow of power to the plasma ions, which is an important factor in the analysis of advanced-fuels. A Hot Ion Mode (HIM) analysis was used to investigate the changes in the minimum ignition requirements for Cat-D and D- 3 He plasmas, due to the changes in the allowable T/sub i/T/sub e/ for ignition from NES and equilibration modifications. Both of these effects have the strongest influence on the ignition requirements for high temperature (>50 keV), low beta (<15%) plasmas, where the cyclotron radiation power loss from the electrons (which is particularly sensitive to changes in the electron temperature) is large

Facile surface modification of silicone rubber with zwitterionic polymers for improving blood compatibility

International Nuclear Information System (INIS)

Liu, Pingsheng; Chen, Qiang; Yuan, Bo; Chen, Mengzhou; Wu, Shishan; Lin, Sicong; Shen, Jian

2013-01-01

A facile approach to modify silicone rubber (SR) membrane for improving the blood compatibility was investigated. The hydrophobic SR surface was firstly activated by air plasma, after which an initiator was immobilized on the activated surface for atom transfer radical polymerization (ATRP). Three zwitterionic polymers were then grafted from SR membrane via surface-initiated atom transfer radical polymerization (SI-ATRP). The surface composition, wettability, and morphology of the membranes before and after modification were characterized by X-ray photoelectron spectroscopy (XPS), static water contact angle (WCA) measurement, and atomic force microscopy (AFM). Results showed that zwitterionic polymers were successfully grafted from SR surfaces, which remarkably improved the wettability of the SR surface. The blood compatibility of the membranes was evaluated by protein adsorption and platelet adhesion tests in vitro. As observed, all the zwitterionic polymer modified surfaces have improved resistance to nonspecific protein adsorption and have excellent resistance to platelet adhesion, showing significantly improved blood compatibility. This work should inspire many creative uses of SR based materials for biomedical applications such as vessel, catheter, and microfluidics. Highlights: • Facile surface modification of silicone rubber with functional brushes • Modified SR surfaces have improved resistance to nonspecific protein adsorption. • Modified SR surfaces have excellent resistance to platelet adhesion. • Zwitteironic surface significant improvement in blood compatibility • Could inspire many creative uses of SR based materials for biomedical

Facile surface modification of silicone rubber with zwitterionic polymers for improving blood compatibility

Energy Technology Data Exchange (ETDEWEB)

Liu, Pingsheng [School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093 (China); Chen, Qiang, E-mail: chem100@nju.edu.cn [School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093 (China); High Technology Research Institute of Nanjing University, Changzhou 213164 (China); Yuan, Bo; Chen, Mengzhou; Wu, Shishan; Lin, Sicong [School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093 (China); Shen, Jian, E-mail: shenj1957@yahoo.com.cn [School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093 (China)

2013-10-15

A facile approach to modify silicone rubber (SR) membrane for improving the blood compatibility was investigated. The hydrophobic SR surface was firstly activated by air plasma, after which an initiator was immobilized on the activated surface for atom transfer radical polymerization (ATRP). Three zwitterionic polymers were then grafted from SR membrane via surface-initiated atom transfer radical polymerization (SI-ATRP). The surface composition, wettability, and morphology of the membranes before and after modification were characterized by X-ray photoelectron spectroscopy (XPS), static water contact angle (WCA) measurement, and atomic force microscopy (AFM). Results showed that zwitterionic polymers were successfully grafted from SR surfaces, which remarkably improved the wettability of the SR surface. The blood compatibility of the membranes was evaluated by protein adsorption and platelet adhesion tests in vitro. As observed, all the zwitterionic polymer modified surfaces have improved resistance to nonspecific protein adsorption and have excellent resistance to platelet adhesion, showing significantly improved blood compatibility. This work should inspire many creative uses of SR based materials for biomedical applications such as vessel, catheter, and microfluidics. Highlights: • Facile surface modification of silicone rubber with functional brushes • Modified SR surfaces have improved resistance to nonspecific protein adsorption. • Modified SR surfaces have excellent resistance to platelet adhesion. • Zwitteironic surface significant improvement in blood compatibility • Could inspire many creative uses of SR based materials for biomedical.

Radiation and combined heat transfer in channels

International Nuclear Information System (INIS)

Tamonis, M.

1986-01-01

This book presents numerical methods of calculation of radiative and combined heat transfer in channel flows of radiating as well as nonradiating media. Results obtained in calculations for flow conditions of combustion products from organic fuel products are given and methods used in determining the spectral optical properties of molecular gases are analyzed. The book presents applications of heat transfer in solving problems. Topic covered are as follows: optical properties of molecular gases; transfer equations for combined heat transfer; experimental technique; convective heat transfer in heated gas flows; radiative heat transfer in gaseous media; combined heat transfer; and radiative and combined heat transfer in applied problems

Subcooled boiling heat transfer correlation to calculate the effects of dissolved gas in a liquid

International Nuclear Information System (INIS)

Zarkasi, Amin S.; Chao, W.W.; Kunze, Jay F.

2004-01-01

The water coolant in most operating power reactor systems is kept free of dissolved gas, so as to minimize corrosion. However, in most research reactors, which operate at temperatures below 70 deg. C, and between 1 and 5 atm. pressure, the dissolved gas remains present in the water coolant system during operation. This dissolved gas can have a significant effect during accident conditions (i.e. a LOCA), when the fluid quickly reaches boiling, coincident with flow stagnation and subsequent flow reversal. A benchmark experiment was conducted, with an electrically heated, closed loop channel, modeling a research reactor fuel coolant channels (2 mm thick). The results showed 'boiling (bubble) noise' occurring before wall temperatures reached saturation, and a significant increase (up to 50%) in the heat transfer coefficient in the subcooled boiling region when in the presence of dissolved gas, compared to degassed water. Since power reactors do not involve dissolved gas, the RELAP safety analysis code does not include any provisions for the effect of dissolved gas on heat transfer. In this work, the effects of the dissolved gas are evaluated for inclusion in the RELAP code, including provision for initiating 'nucleate boiling' at a lower temperature, and a provision for enhancing the heat transfer coefficient during the subcooled boiling region. Instead of relying on Chen's correlation alone, a modification of the superposition method of Bjorge was adopted. (author)

L-dependence in the 6Li induced three nucleon transfer excitation function

International Nuclear Information System (INIS)

Kraus, L.; Linck, I.

1980-01-01

The three nucleon transfer reactions induced by 6 Li on 12 C were studied from 5 to 9 MeV/n. The bell-shaped energy variation is used to select cluster states of progressively higher angular momentum. A modification to the Brink semi-classical model equations is proposed in order to reproduce the observed features

Modification of Ti6Al4V surface by diazonium compounds

Science.gov (United States)

Sandomierski, Mariusz; Buchwald, Tomasz; Strzemiecka, Beata; Voelkel, Adam

2018-02-01

Ti6Al4V alloy is the most commonly used in orthopedic industry as an endoprosthesis. Ti6Al4V exhibits good mechanical properties, except the abrasion resistance. Surface modification of Ti6Al4V in order to obtain organic layer, and then the attachment of the polymer, can allow for overcoming this problem. The aim of the work was the modification of Ti6Al4V surface by diazonium compounds: salt or cation generated in situ and examine the influence of the reducing agent - ascorbic acid, and the temperature of reaction on modification process. Moreover, the simulated body fluid was used for the assessment of the organic layer stability on Ti6Al4V surface. The evaluation of the modification was carried out using the following methods: Raman microspectroscopy, scanning electron microscopy and energy-dispersive X-ray spectroscopy. Higher temperature of modification by 4-hydroxymethylbenzenediazonium cation, provides the largest amount of organic layer on the Ti6Al4V alloy. In the case of the Ti6Al4V modified by Variamine Blue B salt, the amount of organic layer is not dependent on the reaction condition. Moreover, the ascorbic acid and the presence of TiO2 does not effect on the modification. The modified surface is completely coated with the organic layer which is stable in simulated body fluid.

Modifications to POISSON

International Nuclear Information System (INIS)

Harwood, L.H.

1981-01-01

At MSU we have used the POISSON family of programs extensively for magnetic field calculations. In the presently super-saturated computer situation, reducing the run time for the program is imperative. Thus, a series of modifications have been made to POISSON to speed up convergence. Two of the modifications aim at having the first guess solution as close as possible to the final solution. The other two aim at increasing the convergence rate. In this discussion, a working knowledge of POISSON is assumed. The amount of new code and expected time saving for each modification is discussed

An Institutional Framework to Explain the University: Industry Technology Transfer in a Public University of Mexico

OpenAIRE

Puerta Sierra, Lizbeth Magdalena; Marín Vargas, Ma. Enselmina; López Torres, Virginia Guadalupe

2017-01-01

In the last years, studies and modifications to the science and technology regulatory framework in Mexico show the increase in the attention to transfer the research results of professors and researchers from higher education institutions, towards the productive sector with the purpose of generating regional, national and international growth and development. This study has conducted to the search of the factors that determine the increase of linkage activities and technology transfer. Based ...

Covalent versus Charge Transfer Modification of Graphene/Carbon-Nanotubes with Vitamin B1: Co/N/S-C Catalyst toward Excellent Oxygen Reduction.

Science.gov (United States)

Vij, Varun; Tiwari, Jitendra N; Kim, Kwang S

2016-06-29

High-performance nonprecious cathodic catalysts for oxygen reduction are highly demanded for low-temperature polymer electrolyte membrane fuel cells (PEMFCs). Here, we report a noble-meta- free, nitrogen and sulfur codoped graphene(G)/carbon-nanotube(CNT) material decorated with Co nanoparticles (NPs), which serve as catalytic sites for excellent oxygen reduction reaction (ORR) in basic and acidic media. Out of the cathodic catalysts synthesized by either covalent (cov) or charge transfer (CT) modification of graphen oxide (GO) with thiamine (Th: Vitamin B1), ThG/CNT/Co-cov shows more promising ORR properties than ThG/CNT/Co-CT. Catalyst ThG/CNT/Co-cov exhibits onset/halfwave potentials of 0.95/0.86 V in 0.1 M KOH and 0.92/0.83 V in 0.1 M HClO4, which are comparable to those of commercial catalyst Pt/C (0.95/0.86 V). As compared to Pt/C, our catalyst shows higher current densities of 6.72 mA cm(-2) in basic medium and 7.08 mA cm(-2) in acidic medium at 0.55 V (vs reversible hydrogen electrode (RHE)). It also exhibits better catalytic stability and methanol tolerance. High catalytic efficiency and stability of ThG/CNT/Co-cov show a promising prospect of materialization of PEMFCs for clean energy production.

Neutralized ion beam modification of cellulose membranes for study of ion charge effect on ion-beam-induced DNA transfer

Science.gov (United States)

Prakrajang, K.; Sangwijit, K.; Anuntalabhochai, S.; Wanichapichart, P.; Yu, L. D.

2012-02-01

Low-energy ion beam biotechnology (IBBT) has recently been rapidly developed worldwide. Ion-beam-induced DNA transfer is one of the important applications of IBBT. However, mechanisms involved in this application are not yet well understood. In this study plasma-neutralized ion beam was applied to investigate ion charge effect on induction of DNA transfer. Argon ion beam at 7.5 keV was neutralized by RF-driven plasma in the beam path and then bombarded cellulose membranes which were used as the mimetic plant cell envelope. Electrical properties such as impedance and capacitance of the membranes were measured after the bombardment. An in vitro experiment on plasmid DNA transfer through the cellulose membrane was followed up. The results showed that the ion charge input played an important role in the impedance and capacitance changes which would affect DNA transfer. Generally speaking, neutral particle beam bombardment of biologic cells was more effective in inducing DNA transfer than charged ion beam bombardment.

Fatty acids, essential oil, and phenolics modifications of black cumin fruit under NaCl stress conditions.

Science.gov (United States)

Bourgou, Soumaya; Bettaieb, Iness; Saidani, Moufida; Marzouk, Brahim

2010-12-08

This research evaluated the effect of saline conditions on fruit yield, fatty acids, and essential oils compositions and phenolics content of black cumin (Nigella sativa). This plant is one of the most commonly found aromatics in the Mediterranean kitchen. Increasing NaCl levels to 60 mM decreased significantly the fruits yield by 58% and the total fatty acids amount by 35%. Fatty acids composition analysis indicated that linoleic acid was the major fatty acid (58.09%) followed by oleic (19.21%) and palmitic (14.77%) acids. Salinity enhanced the linoleic acid percentage but did not affect the unsaturation degree of the fatty acids pool and thus the oil quality. The essential oil yield was 0.39% based on the dry weight and increased to 0.53, 0.56, and 0.72% at 20, 40, and 60 mM NaCl. Salinity results on the modification of the essential oil chemotype from p-cymene in controls to γ-terpinene/p-cymene in salt-stressed plants. The amounts of total phenolics were lower in the treated plants. Salinity decreased mainly the amount of the major class, benzoics acids, by 24, 29, and 44% at 20, 40, and 60 mM NaCl. The results suggest that salt treatment may regulate bioactive compounds production in black cumin fruits, influencing their nutritional and industrial values.

Engineering Task Plan for Hose-In-Hose Transfer Lines for the Interim Stabilization Program

International Nuclear Information System (INIS)

RUNG, M.P.

2000-01-01

This document is the Engineering Task Plan for the engineering, design services, planning, project integration and management support for the design, modification, installation and testing of an over ground transfer (OGT) system to support the interim stabilization of nine tanks in the 241-S/SX Tank Farms

41 CFR 101-39.105-1 - Transfers from discontinued or curtailed fleet management systems.

Science.gov (United States)

2010-07-01

... discontinued or curtailed fleet management systems. 101-39.105-1 Section 101-39.105-1 Public Contracts and... AVIATION, TRANSPORTATION, AND MOTOR VEHICLES 39-INTERAGENCY FLEET MANAGEMENT SYSTEMS 39.1-Establishment, Modification, and Discontinuance of Interagency Fleet Management Systems § 101-39.105-1 Transfers from...

Epigenetic modifications: An important mechanism in diabetic disturbances.

Science.gov (United States)

Rorbach-Dolata, Anna; Kubis, Adriana; Piwowar, Agnieszka

2017-11-29

In the search for explanations of diabetes pathomechanisms, especially the development of its vascular complications (micro- and macrovascular ), although current, good metabolic control of diabetes, attention was drawn to the role of epigenetic inheritance associated with epigenetic modifications of histone proteins and DNA in hyperglycemia conditions. This study showed the significant role of DNA methylation and histone epigenetic modifications (a different nature and a different degree) in the transmission of information that is not connected with gene inheritance but concerns the persistent changes induced by hyperglycemia..Attention was paid to the role of DNA methylation of pancreatic cells in the pathogenesis of type 1 diabetes, but also type 2. The important role of DNA methylation changes in a so-called intrauterine growth restriction (IUGR) as reason of subsequent development of diabetes was particularly emphasized. In the pathogenesis of type 2 diabetes and its complications, especially microvascular complications, the greatest share and importance of epigenetic modifications on mitochondrial DNA metylation are the most important. The multidirectionality Complicaand complexity of epigenetic modifications of histone proteins indicate their importance in the development of diabetic disturbances. An especially important role is attributed to methylation and acetylation of histone proteins, in particular on arginine and lysine, whose changes occur most frequently. Moreover, epigenetic modifications of the enzymes, especially methylases, responsible for these processes are the underlying. It has been indicated that the identification of epigenetic differences within the DNA or histone proteins may be a useful prognostic biomarker of susceptibility to the disease development in the future. Moreover, they may become a potential target for future therapeutic interventions for clinical disorders in diabetes.

Surface modification of malachite with ethanediamine and its effect on sulfidization flotation

Science.gov (United States)

Feng, Qicheng; Zhao, Wenjuan; Wen, Shuming

2018-04-01

Ethanediamine was used to modify the mineral surface of malachite to improve its sulfidization and flotation behavior. The activation mechanism was investigated by adsorption experiments, X-ray photoelectron spectroscopy (XPS) analysis, and zeta potential measurements. Microflotation experiments showed that the flotation recovery of malachite was enhanced after the pretreatment of the mineral particles with ethanediamine prior to the addition of Na2S. Adsorption tests revealed that numerous sulfide ion species in the pulp solution were transferred onto the mineral surface through the formation of more copper sulfide species. This finding was confirmed by the results of the XPS measurements. Ethanediamine modification not only increased the contents of copper sulfide species on the malachite surface but also enhanced the reactivity of the sulfidization products. During sulfidization, Cu(II) species on the mineral surface were reduced into Cu(I) species, and the percentages of S22- and Sn2- relative to the total S increased after modification, resulting in increased surface hydrophobicity. The results of zeta potential measurements showed that the ethanediamine-modified mineral surface adsorbed with more sulfide ion species was advantageous to the attachment of xanthate species, thereby improving malachite floatability. The proposed ethanediamine modification followed by sulfidization xanthate flotation exhibits potential for industrial application.

Evaluation of gap heat transfer model in ELESTRES for CANDU fuel element under normal operating conditions

International Nuclear Information System (INIS)

Lee, Kang Moon; Ohn, Myung Ryong; Im, Hong Sik; Choi, Jong Hoh; Hwang, Soon Taek

1995-01-01

The gap conductance between the fuel and the sheath depends strongly on the gap width and has a significant influence on the amount of initial stored energy. The modified Ross and Stoute gap conductance model in ELESTRES is based on a simplified thermal deformation model for steady-state fuel temperature calculations. A review on a series of experiments reveals that fuel pellets crack, relocate, and are eccentrically positioned within the sheath rather than solid concentric cylinders. In this paper, the two recently-proposed gap conductance models (offset gap model and relocated gap model) are described and are applied to calculate the fuel-sheath gap conductances under experimental conditions and normal operating conditions in CANDU reactors. The good agreement between the experimentally-inferred and calculated gap conductance values demonstrates that the modified Ross and Stoute model was implemented correctly in ELESTRES. The predictions of the modified Ross and Stoute model provide conservative values for gap heat transfer and fuel surface temperature compared to the offset gap and relocated gap models for a limiting power envelope. 13 figs., 3 tabs., 16 refs. (Author)

Transfer of accidentally released radionuclides in agricultural systems (TARRAS)

International Nuclear Information System (INIS)

Cancio, D.; Maubert, Colle; Rauret, G.; Grandison, A.S.

1993-01-01

The aim of this project is to contribute to the reliability of radiological assessment methods and establish a scientific base for the design of post-accident countermeasures. Three main aspects are considered in this project: A simulated accidental source term is used and the behaviour of aerosol deposits containing Sr, Cs and Ag isotopes are followed in some European soil-crop systems; the modification of radionuclide transfer rates through the food chain by well established food processing techniques is studied for Sr, Cs, Co and Ru; the project includes a study on the specific mediterranean diet and transfer data that are compared with currently used generic parameters. Seven contributions of the project for the reporting period are presented. (R.P.) 11 figs., 12 tabs

Human factors in design modifications: panel alternative stop in Almaraz

International Nuclear Information System (INIS)

Roman, Y.; Bote, J.

2015-01-01

Human Factors Engineering has acquired a crucial role in the development of any design modification (DM), where every aspect relative to any interaction with the human user has to be taken into account at any stage thereof. Considering this, during the last years, Almaraz Nuclear Powe Plants has developed a program of Human Factors Engineering in order to reach the internationally recognized standards or systematic collected on NUREG 0711 Human Factors Engineering Program Review Model (NRC). One of the most important projects of this program at Almaraz Nuclear Power Plant has been the implementation of the Alternative Stop Panel and their corresponding Transfer Panels. (Author)

A Chemical-Adsorption Strategy to Enhance the Reaction Kinetics of Lithium-Rich Layered Cathodes via Double-Shell Surface Modification.

Science.gov (United States)

Guo, Lichao; Li, Jiajun; Cao, Tingting; Wang, Huayu; Zhao, Naiqin; He, Fang; Shi, Chunsheng; He, Chunnian; Liu, Enzuo

2016-09-21

Sluggish surface reaction kinetics hinders the power density of Li-ion battery. Thus, various surface modification techniques have been applied to enhance the electronic/ionic transfer kinetics. However, it is challenging to obtain a continuous and uniform surface modification layer on the prime particles with structure integration at the interface. Instead of classic physical-adsorption/deposition techniques, we propose a novel chemical-adsorption strategy to synthesize double-shell modified lithium-rich layered cathodes with enhanced mass transfer kinetics. On the basis of experimental measurement and first-principles calculation, MoO2S2 ions are proved to joint the layered phase via chemical bonding. Specifically, the Mo-O or Mo-S bonds can flexibly rotate to bond with the cations in the layered phase, leading to the good compatibility between the thiomolybdate adsorption layer and layered cathode. Followed by annealing treatment, the lithium-excess-spinel inner shell forms under the thiomolybdate adsorption layer and functions as favorable pathways for lithium and electron. Meanwhile, the nanothick MoO3-x(SO4)x outer shell protects the transition metal from dissolution and restrains electrolyte decomposition. The double-shell modified sample delivers an enhanced discharge capacity almost twice as much as that of the unmodified one at 1 A g(-1) after 100 cycles, demonstrating the superiority of the surface modification based on chemical adsorption.

Effective donor cell fusion conditions for production of cloned dogs by somatic cell nuclear transfer.

Science.gov (United States)

Park, JungEun; Oh, HyunJu; Hong, SoGun; Kim, MinJung; Kim, GeonA; Koo, OkJae; Kang, SungKeun; Jang, Goo; Lee, ByeongChun

2011-03-01

As shown by the birth of the first cloned dog 'Snuppy', a protocol to produce viable cloned dogs has been reported. In order to evaluate optimum fusion conditions for improving dog cloning efficiency, in vivo matured oocytes were reconstructed with adult somatic cells from a female Pekingese using different fusion conditions. Fusion with needle vs chamber methods, and with low vs high pulse strength was compared by evaluating fusion rate and in vivo development of canine cloned embryos. The fusion rates in the high voltage groups were significantly higher than in the low voltage groups regardless of fusion method (83.5 vs 66.1% for the needle fusion method, 67.4 vs 37.9% for the fusion chamber method). After embryo transfer, one each pregnancy was detected after using the needle fusion method with high and low voltage and in the chamber fusion method with high voltage, whereas no pregnancy was detected using the chamber method with low voltage. However, only the pregnancy from the needle fusion method with high voltage was maintained to term and one healthy puppy was delivered. The results of the present study demonstrated that two DC pulses of 3.8 to 4.0 kV/cm for 15 μsec using the needle fusion method were the most effective method for the production of cloned dogs under the conditions of this experiment. Copyright © 2011 Elsevier Inc. All rights reserved.

Impact of acid and oxidative modifications, single or dual, of sorghum starch on biodegradable films.

Science.gov (United States)

Biduski, Bárbara; Silva, Francine Tavares da; Silva, Wyller Max da; Halal, Shanise Lisie de Mello El; Pinto, Vania Zanella; Dias, Alvaro Renato Guerra; Zavareze, Elessandra da Rosa

2017-01-01

The objective of this study was to evaluate the effects of acid and oxidation modifications on sorghum starch, as well as the effect of dual modification of starch on the physical, morphological, mechanical, and barrier properties of biodegradable films. The acid modification was performed with 3% lactic acid and the oxidation was performed with 1.5% active chlorine. For dual modification, the acid modification was performed first, followed by oxidation under the same conditions as above. Both films of the oxidized starches, single and dual, had increased stiffness, providing a higher tensile strength and lower elongation when compared to films based on native and single acid modified starches. However, the dual modification increased the water vapor permeability of the films without changing their solubility. The increase in sorghum starch concentration in the filmogenic solution increased the thickness, water vapor permeability, and elongation of the films. Copyright © 2016. Published by Elsevier Ltd.

Theory of nuclear heavy-ion direct transfer reactions

International Nuclear Information System (INIS)

Crowley, B.J.B.

1979-01-01

We review the distorted-wave approach to direct transfer reactions and draw attention to some of the shortcomings of current theories. We show that a reformulated form of the distorted-wave Born approximation (DWBA) for transfer can lead to important simplifications of the theory, which are valid for nuclear heavy-ion induced reactions at energies > or approx. =MeV/nucleon. In particular, in the semiclassical limit, it leads to a new and simple formula for the transfer t-matrix which includes all the essential physics while offering several important advantages over standard ''full-recoil finite-range'' DWBA. One such advantage is that the new formula is more transparent in that it is amendable to interpretation and analytical manipulation. At high-energy it is shown to reduce to one earlier deduced using eikonal-DWBA. The conditions for the validity of the new theory are discussed in detail. They are shown to be generally well satisfied for small-mass transfer between heavy-ions at energies at or above those particularly favour transfer (> or approx. =10 MeV/nucleon for transfer of valence nucleons). The restriction to small mass is not due to any recoil approximation; in fact, it is only a necessary restriction at certain energies. The theory treats recoil exactly. Consideration of the optimum dynamical conditions for transfer leads to a set of matching conditions. The presence of hitherto neglected absorption, arising from dynamical effects of poor matching, it suggested and qualitatively discussed. Condition under which such absorption may be neglected are derived. Results of numerical calculations are presented showing that the theory is capable of good agreement with standard full-recoil finite-range DWBA, and that it is capable of giving at least as good an account of experimental data for nucleon-transfer between heavy-ions at energies approx.10 MeV/nucleon

Effect of Brazil's conditional cash transfer programme on tuberculosis incidence.

Science.gov (United States)

Nery, J S; Rodrigues, L C; Rasella, D; Aquino, R; Barreira, D; Torrens, A W; Boccia, D; Penna, G O; Penna, M L F; Barreto, M L; Pereira, S M

2017-07-01

To evaluate the impact of the Brazilian cash transfer programme (Bolsa Família Programme, BFP) on tuberculosis (TB) incidence in Brazil from 2004 to 2012. We studied tuberculosis surveillance data using a combination of an ecological multiple-group and time-trend design covering 2458 Brazilian municipalities. The main independent variable was BFP coverage and the outcome was the TB incidence rate. All study variables were obtained from national databases. We used fixed-effects negative binomial models for panel data adjusted for selected covariates and a variable representing time. After controlling for covariates, TB incidence rates were significantly reduced in municipalities with high BFP coverage compared with those with low and intermediate coverage (in a model with a time variable incidence rate ratio = 0.96, 95%CI 0.93-0.99). This was the first evidence of a statistically significant association between the increase in cash transfer programme coverage and a reduction in TB incidence rate. Our findings provide support for social protection interventions for tackling TB worldwide.

Intra-population variation in behavior modification by the acanthocephalan Acanthocephalus dirus: are differences mediated by host condition?

Science.gov (United States)

Caddigan, Sara C; Barkauskas, Rima T; Sparkes, Timothy C

2014-11-01

The acanthocephalan parasite Acanthocephalus dirus infects the freshwater isopod Caecidotea intermedius as an intermediate host before completing its life cycle in a fish. Male C. intermedius infected by A. dirus parasites are less likely to engage in mating behavior than uninfected males but there is a significant intra-population variation in the occurrence of this behavioral change. Previous studies on uninfected isopods have shown that glycogen content is a predictor of male mating behavior and we examined whether the intra-population variation in the mating behavior of infected male C. intermedius could be explained by this relationship. A field-based behavioral experiment was used to quantify intra-population variation in male mating behavior, which showed that 50% of infected males were responsive to females and 50% were not responsive. Biochemical analysis of responsive and non-responsive males revealed that glycogen content was a predictor of the mating behavior for uninfected males but was not a predictor of mating behavior for infected males. For infected males, parasite intensity was a predictor of mating behavior. Males that contained more A. dirus parasites were less likely to undergo modification of mating behavior. We propose that the intra-population variation in the mating behavior of infected C. intermedius identified in nature was not mediated by host condition.

Electrothermal atomisation atomic absorption conditions and matrix modifications for determining antimony, arsenic, bismuth, cadmium, gallium, gold, indium, lead, molybdenum, palladium, platinum, selenium, silver, tellurium, thallium and tin following back-extraction of organic aminohalide extracts

Science.gov (United States)

Clark, J.R.

1986-01-01

A multi-element organic-extraction and back-extraction procedure, that had been developed previously to eliminate matrix interferences in the determination of a large number of trace elements in complex materials such as geological samples, produced organic and aqueous solutions that were complex. Electrothermal atomisation atomic absorption conditions and matrix modifications have been developed for 13 of the extracted elements (Ag, As, Au, Bi, Cd, Ga, In, Pb, Sb, Se, Sn, Te and Tl) that enhance sensitivity, alleviate problems resulting from the complex solutions and produce acceptable precision. Platinum, Pd and Mo can be determined without matrix modification directly on the original unstripped extracts.

Abusive Transfer Pricing and Economic Activity

DEFF Research Database (Denmark)

Nielsen, Søren Bo; Schindler, Dirk; Schjelderup, Guttorm

This paper investigates how concealment costs of transfer pricing and the probability of detection affect transfer pricing and firm behavior. We find that transfer pricing in intermediate production factors does not affect real activity of a multinational firm if the firm’s concealment effort...... its production structure. A policy implication of the paper is that it should be preferable to condition audits on the amount of income shifted rather than on the distortion of the transfer price proper. Another policy finding is that improving the quality of tax law might be superior to higher...

Surface morphological modification of crosslinked hydrophilic co-polymers by nanosecond pulsed laser irradiation

Energy Technology Data Exchange (ETDEWEB)

Primo, Gastón A.; Alvarez Igarzabal, Cecilia I. [IMBIV (CONICET), Departamento de Química Orgánica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Haya de la Torre y Medina Allende, Edificio de Ciencias II, Ciudad Universitaria, Córdoba X5000HUA (Argentina); Pino, Gustavo A.; Ferrero, Juan C. [INFIQC (CONICET), Departamento de Fisicoquímica, Facultad de Ciencias Químicas, and Centro Láser de Ciencias Moleculares, Universidad Nacional de Córdoba, Córdoba X5000IUS (Argentina); Rossa, Maximiliano, E-mail: mrossa@fcq.unc.edu.ar [INFIQC (CONICET), Departamento de Fisicoquímica, Facultad de Ciencias Químicas, and Centro Láser de Ciencias Moleculares, Universidad Nacional de Córdoba, Córdoba X5000IUS (Argentina)

2016-04-30

Graphical abstract: - Highlights: • Laser-induced surface modification of crosslinked hydrophilic co-polymers by ns pulses. • Formation of ablation craters observed under most of the single-pulse experimental conditions. • UV laser foaming of dried hydrogel samples resulting from single- and multiple-pulse experiments. • Threshold values of the incident laser fluence reported for the observed surface modifications. • Lower threshold fluences for acrylate-based, compared to acrylamide-based hydrogels. - Abstract: This work reports an investigation of the surface modifications induced by irradiation with nanosecond laser pulses of ultraviolet and visible wavelengths on crosslinked hydrophilic co-polymeric materials, which have been functionalized with 1-vinylimidazole as a co-monomer. A comparison is made between hydrogels differing in the base co-monomer (N,N-dimethylaminoethyl methacrylate and N-[3-(dimethylamino)propyl] methacrylamide) and in hydration state (both swollen and dried states). Formation of craters is the dominant morphological change observed by ablation in the visible at 532 nm, whereas additional, less aggressive surface modifications, chiefly microfoams and roughness, are developed in the ultraviolet at 266 nm. At both irradiation wavelengths, threshold values of the incident laser fluence for the observation of the various surface modifications are determined under single-pulse laser irradiation conditions. It is shown that multiple-pulse irradiation at 266 nm with a limited number of laser shots can be used alternatively for generating a regular microfoam layer at the surface of dried hydrogels based on N,N-dimethylaminoethyl methacrylate. The observations are rationalized on the basis of currently accepted mechanisms for laser-induced polymer surface modification, with a significant contribution of the laser foaming mechanism. Prospective applications of the laser-foamed hydrogel matrices in biomolecule immobilization are suggested.

Flow and mass transfer downstream of an orifice under flow accelerated corrosion conditions

International Nuclear Information System (INIS)

Ahmed, Wael H.; Bello, Mufatiu M.; El Nakla, Meamer; Al Sarkhi, Abdelsalam

2012-01-01

Highlights: ► Mass transfer downstream of orifices was numerically and experimentally investigated. ► The surface wear pattern is measured and used to validate the present numerical results. ► The maximum mass transfer coefficient found to occur at approximately 2–3 pipe diameters downstream of the orifice. ► The FAC wear rates were correlated with the turbulence kinetic energy and wall mass transfer in terms of Sherwood number. ► The current study offered very useful information for FAC engineers for better preparation of nuclear plant inspection scope. - Abstract: Local flow parameters play an important role in characterizing flow accelerated corrosion (FAC) downstream of sudden area change in power plant piping systems. Accurate prediction of the highest FAC wear rate locations enables the mitigation of sudden and catastrophic failures, and the improvement of the plant capacity factor. The objective of the present study is to evaluate the effect of the local flow and mass transfer parameters on flow accelerated corrosion downstream of an orifice. In the present study, orifice to pipe diameter ratios of 0.25, 0.5 and 0.74 were investigated numerically by solving the continuity and momentum equations at Reynolds number of Re = 20,000. Laboratory experiments, using test sections made of hydrocal (CaSO 4 ·½H 2 O) were carried out in order to determine the surface wear pattern and validate the present numerical results. The numerical results were compared to the plants data as well as to the present experiments. The maximum mass transfer coefficient found to occur at approximately 2–3 pipe diameters downstream of the orifice. This location was also found to correspond to the location of elevated turbulent kinetic energy generated within the flow separation vortices downstream of the orifice. The FAC wear rates were correlated with the turbulence kinetic energy and wall mass transfer in terms of Sherwood number. The current study found to offer very

Heat transfer between adsorbate and laser-heated hot electrons

International Nuclear Information System (INIS)

Ueba, H; Persson, B N J

2008-01-01

Strong short laser pulses can give rise to a strong increase in the electronic temperature at metal surfaces. Energy transfer from the hot electrons to adsorbed molecules may result in adsorbate reactions, e.g. desorption or diffusion. We point out the limitations of an often used equation to describe the heat transfer process in terms of a friction coupling. We propose a simple theory for the energy transfer between the adsorbate and hot electrons using a newly introduced heat transfer coefficient, which depends on the adsorbate temperature. We calculate the transient adsorbate temperature and the reaction yield for a Morse potential as a function of the laser fluency. The results are compared to those obtained using a conventional heat transfer equation with temperature-independent friction. It is found that our equation of energy (heat) transfer gives a significantly lower adsorbate peak temperature, which results in a large modification of the reaction yield. We also consider the heat transfer between different vibrational modes excited by hot electrons. This mode coupling provides indirect heating of the vibrational temperature in addition to the direct heating by hot electrons. The formula of heat transfer through linear mode-mode coupling of two harmonic oscillators is applied to the recent time-resolved study of carbon monoxide and atomic oxygen hopping on an ultrafast laser-heated Pt(111) surface. It is found that the maximum temperature of the frustrated translation mode can reach high temperatures for hopping, even when direct friction coupling to the hot electrons is not strong enough

Genetic Modification of the Lung Directed Toward Treatment of Human Disease.

Science.gov (United States)

Sondhi, Dolan; Stiles, Katie M; De, Bishnu P; Crystal, Ronald G

2017-01-01

Genetic modification therapy is a promising therapeutic strategy for many diseases of the lung intractable to other treatments. Lung gene therapy has been the subject of numerous preclinical animal experiments and human clinical trials, for targets including genetic diseases such as cystic fibrosis and α1-antitrypsin deficiency, complex disorders such as asthma, allergy, and lung cancer, infections such as respiratory syncytial virus (RSV) and Pseudomonas, as well as pulmonary arterial hypertension, transplant rejection, and lung injury. A variety of viral and non-viral vectors have been employed to overcome the many physical barriers to gene transfer imposed by lung anatomy and natural defenses. Beyond the treatment of lung diseases, the lung has the potential to be used as a metabolic factory for generating proteins for delivery to the circulation for treatment of systemic diseases. Although much has been learned through a myriad of experiments about the development of genetic modification of the lung, more work is still needed to improve the delivery vehicles and to overcome challenges such as entry barriers, persistent expression, specific cell targeting, and circumventing host anti-vector responses.

Biokinetics of cadmium, selenium, and zinc in freshwater alga Scenedesmus obliquus under different phosphorus and nitrogen conditions and metal transfer to Daphnia magna

International Nuclear Information System (INIS)

Yu Riqing; Wang Wenxiong

2004-01-01

The uptake of Cd, Se(IV) and Zn by the freshwater alga Scenedesmus obliquus and the subsequent transfer and release budget in Daphnia magna were investigated under different nutrient additions and cell incubation conditions. An increase in ambient phosphate concentrations from 0.5 μmol l -1 to 50 μmol l -1 significantly increased the intracellular accumulation of Cd (by 18x) and Zn (by 5x), but decreased the accumulation of Se (by 126x) in the alga. The percentage of these metals distributing in the intracellular pool of algae also increased substantially with increasing ambient P concentrations. Nitrate addition from 5.0 to 200 μmol l -1 did not influence the uptake of any of the three metals, although a significant decrease in the intracellular Se distribution was observed. Radiolabeled algae under different nutrient manipulations (semi-continuous culture, starvation, and P-pulse treatments) were used to measure trophic transfer assimilation efficiency (AE) in Daphnia. When the algal cells were grown in a semi-continuous culture, starved for N and P, or were treated with P-pulse, the AEs of Cd and Zn were generally independent of the nutritional conditions, but the Se AE was significantly affected by different P levels. The efflux rate constants, determined during 10 d depuration following 7 days of dietary uptake, decreased significantly for Cd and Zn, but were relatively constant for Se with increasing P concentration. N-addition caused no effect on the metal efflux rate constants. P- or N-additions did not influence the release budget (including molting, neonates, excretion and feces) for all three elements in Daphnia. Our study indicated that phosphate enrichment may substantially increase metal uptake in green alga S. obliquus. Responses of trophic transfer in Daphnia to nutrient enrichment were metal specific. P-enrichment can possibly lead to considerable decrease on Se transfer from algae to zooplankton. - Phosphorous enrichment influences metal uptake

Biokinetics of cadmium, selenium, and zinc in freshwater alga Scenedesmus obliquus under different phosphorus and nitrogen conditions and metal transfer to Daphnia magna

Energy Technology Data Exchange (ETDEWEB)

Yu Riqing; Wang Wenxiong

2004-06-01

The uptake of Cd, Se(IV) and Zn by the freshwater alga Scenedesmus obliquus and the subsequent transfer and release budget in Daphnia magna were investigated under different nutrient additions and cell incubation conditions. An increase in ambient phosphate concentrations from 0.5 {mu}mol l{sup -1} to 50 {mu}mol l{sup -1} significantly increased the intracellular accumulation of Cd (by 18x) and Zn (by 5x), but decreased the accumulation of Se (by 126x) in the alga. The percentage of these metals distributing in the intracellular pool of algae also increased substantially with increasing ambient P concentrations. Nitrate addition from 5.0 to 200 {mu}mol l{sup -1} did not influence the uptake of any of the three metals, although a significant decrease in the intracellular Se distribution was observed. Radiolabeled algae under different nutrient manipulations (semi-continuous culture, starvation, and P-pulse treatments) were used to measure trophic transfer assimilation efficiency (AE) in Daphnia. When the algal cells were grown in a semi-continuous culture, starved for N and P, or were treated with P-pulse, the AEs of Cd and Zn were generally independent of the nutritional conditions, but the Se AE was significantly affected by different P levels. The efflux rate constants, determined during 10 d depuration following 7 days of dietary uptake, decreased significantly for Cd and Zn, but were relatively constant for Se with increasing P concentration. N-addition caused no effect on the metal efflux rate constants. P- or N-additions did not influence the release budget (including molting, neonates, excretion and feces) for all three elements in Daphnia. Our study indicated that phosphate enrichment may substantially increase metal uptake in green alga S. obliquus. Responses of trophic transfer in Daphnia to nutrient enrichment were metal specific. P-enrichment can possibly lead to considerable decrease on Se transfer from algae to zooplankton. - Phosphorous enrichment

Solar sail time-optimal interplanetary transfer trajectory design

International Nuclear Information System (INIS)

Gong Shengpin; Gao Yunfeng; Li Junfeng

2011-01-01

The fuel consumption associated with some interplanetary transfer trajectories using chemical propulsion is not affordable. A solar sail is a method of propulsion that does not consume fuel. Transfer time is one of the most pressing problems of solar sail transfer trajectory design. This paper investigates the time-optimal interplanetary transfer trajectories to a circular orbit of given inclination and radius. The optimal control law is derived from the principle of maximization. An indirect method is used to solve the optimal control problem by selecting values for the initial adjoint variables, which are normalized within a unit sphere. The conditions for the existence of the time-optimal transfer are dependent on the lightness number of the sail and the inclination and radius of the target orbit. A numerical method is used to obtain the boundary values for the time-optimal transfer trajectories. For the cases where no time-optimal transfer trajectories exist, first-order necessary conditions of the optimal control are proposed to obtain feasible solutions. The results show that the transfer time decreases as the minimum distance from the Sun decreases during the transfer duration. For a solar sail with a small lightness number, the transfer time may be evaluated analytically for a three-phase transfer trajectory. The analytical results are compared with previous results and the associated numerical results. The transfer time of the numerical result here is smaller than the transfer time from previous results and is larger than the analytical result.

Experimental analysis of heat transfer within the AP600 containment under postulated accident conditions

International Nuclear Information System (INIS)

Anderson, M.H.; Corradini, M.L.

1998-01-01

The new AP600 reactor designed by Westinghouse uses a passive safety system relying on heat removal by condensation to keep the containment within the design limits of pressure and temperature. Even though some research has been done so far in this regard, there are some uncertainties concerning the behavior of the system under postulated accident conditions. In this paper, steam condensation onto the internal surfaces of the AP600 containment walls has been investigated in two scaled vessels with similar aspect ratios to the actual AP600. The heat transfer degradation in the presence of noncondensable gas has been analyzed for different noncondensable mixtures of air and helium (hydrogen simulant). Molar fractions of noncondensables/steam ranged from (0.4-4.0) and helium concentrations in the noncondensable mixture were 0-50% by volume. In addition, the effects of the bulk temperatures, the mass fraction of noncondensable/steam, the cold wall surface temperature, the pressure, noncondensable composition, and the inclination of the condensing surface were studied. It was found that the heat transfer coefficients ranged from 50 to 800 J s -1 K -1 m -2 with the highest for high wall temperatures at high pressure and low noncondensable molar fractions. The effect of a light gas (helium) in the noncondensable mixture were found to be negligible for concentrations less than approximately 35 molar percent but could result in stratification at higher concentrations. The complete study gives a large and relatively complete data base on condensation within a scaled AP600 containment structure, providing an invaluable set of data against which to validate models. In addition, specific areas requiring further investigation are summarized. (orig.)

Constructing Functional Ionic Membrane Surface by Electrochemically Mediated Atom Transfer Radical Polymerization

Directory of Open Access Journals (Sweden)

Fen Ran

2016-01-01

Full Text Available The sodium polyacrylate (PAANa contained polyethersulfone membrane that was fabricated by preparation of PES-NH2 via nonsolvent phase separation method, the introduction of bromine groups as active sites by grafting α-Bromoisobutyryl bromide, and surface-initiated electrochemically atom transfer radical polymerization (SI-eATRP of sodium acrylate (AANa on the surface of PES membrane. The polymerization could be controlled by reaction condition, such as monomer concentration, electric potential, polymerization time, and modifier concentration. The membrane surface was uniform when the monomer concentration was 0.9 mol/L, the electric potential was −0.12 V, the polymerization time was 8 h, and the modifier concentration was 2 wt.%. The membrane showed excellent hydrophilicity and blood compatibility. The water contact angle decreased from 84° to 68° and activated partial thromboplastin increased from 51 s to 84 s after modification of the membranes.

Effect of daily temperature range on respiratory health in Argentina and its modification by impaired socio-economic conditions and PM_1_0 exposures

International Nuclear Information System (INIS)

Carreras, Hebe; Zanobetti, Antonella; Koutrakis, Petros

2015-01-01

Epidemiological investigations regarding temperature influence on human health have focused on mortality rather than morbidity. In addition, most information comes from developed countries despite the increasing evidence that climate change will have devastating impacts on disadvantaged populations living in developing countries. In the present study, we assessed the impact of daily temperature range on upper and lower respiratory infections in Cordoba, Argentina, and explored the effect modification of socio-economic factors and influence of airborne particles We found that temperature range is a strong risk factor for admissions due to both upper and lower respiratory infections, particularly in elderly individuals, and that these effects are more pronounced in sub-populations with low education level or in poor living conditions. These results indicate that socio-economic factors are strong modifiers of the association between temperature variability and respiratory morbidity, thus they should be considered in risk assessments. - Highlights: • Daily temperature range is a strong risk factor for respiratory infections. • Low education level and poor living conditions are strong modifiers of this relationship. • In Cordoba city higher risk for respiratory infections were observed during summertime. - Daily temperature range is a strong risk factor for respiratory infections, particularly for populations with low educational level or poor living conditions.

Proton-Conducting Sulfonated Ionomers by Chemical Modification and Atom Transfer Radical Polymerization

DEFF Research Database (Denmark)

Nielsen, Mads Møller

The cornerstone in this dissertation is made up by three individual assessments of the diversity in the macromolecular landscape that can be obtained by applying relatively few efficient chemical tools. The intention is to gain deeper knowledge on the chemical tuning of proton exchange membranes...... of hydrocarbon macromolecular architectures, PSU with postsulfonated polystyrene (PS) grafts are investigated. Here, IEC is controlled through the degree of substitution, the graft length and DS. The grafting is performed with atom transfer radical polymerization (ATRP). The third assessment is dedicated...... of control by ATRP and click chemistry enables a wide selection of polymer structures with the handles: degree of substitution (DS), polymerization and sulfonation, and blending....

Mass transfer effects in feeder flow-accelerated corrosion wall thinning

International Nuclear Information System (INIS)

Pietralik, J.

2008-01-01

Flow conditions play a dominant role in Flow-Accelerated Corrosion (FAC) under certain conditions, e.g., in CANDU feeders. While chemistry and materials set the overall potential for FAC, flow conditions determine the local distribution of wall thinning. Recent plant data of feeders and laboratory tests confirms that there is a close relationship between local flow conditions, expressed by mass transfer coefficient, and FAC rate in CANDU feeder bends. The knowledge of local effects can be useful for minimizing the number of inspected components, predicting the location of the highest FAC rate for a given piping component, and determining what components or feeders should be replaced. A similar evaluation applies also to FAC in heat transfer equipment such as heat exchangers and steam generators. The objective of this paper is to examine the relationship between FAC rate and local mass transfer parameters. For FAC where the flow is dominant, the FAC rate is proportional to mass flux of ferrous ions. The mass flux is the product of the mass transfer coefficient and the concentration difference, or degree of saturation. The mass transfer coefficient describes the intensity of the transport of corrosion products (ferrous ions) from the oxide-water interface into the bulk water. Therefore, this parameter can be used for predicting the local distribution of FAC rate in the mass-transfer controlled FAC. The degree of saturation reduces the mass flux, thus reducing the FAC rate. This effect can be significant in long piping, e.g., in outlet feeders. The paper presents plant and laboratory evidence for the relationship between local mass transfer conditions and the FAC rate. It shows correlations for mass transfer coefficient in components that are highly susceptible to FAC and most important flow parameters that affect mass transfer coefficient. The role of surface roughness, wall shear stress, and local turbulence is also discussed. (author)

Proton-coupled electron transfer promotes the reduction of ferrylmyoglobin by uric acid under physiological conditions

DEFF Research Database (Denmark)

de Zawadzki, Andressa; Cardoso, Daniel R.; Skibsted, Leif Horsfelt

2017-01-01

The hypervalent muscle pigment ferrylmyoglobin, MbFe(IV)]O, is not reduced by urate monoanions at physiological conditions despite a strong driving force of around 30 kJ mol1 while for low pH, uric acid was found to reduce protonated ferrylmyoglobin, MbFe(IV)]O,H+, efficiently in a bimolecular...... reaction with k1 ¼ 1.1 0.1 103 L mol1 s1, DH‡ ¼ 66.1 0.1 kJ mol1 and DS‡ ¼ 35.2 0.2 J mol1 K1. For intermediate pH, like for anaerobic muscles and for meat, proton-oupled electron transfer occurs in a transition state, {MbFe(IV)]O/H+/urate}‡, which is concluded to be formed from uric acid and Mb...... in uric acid concentration may serve as an inherent protection against radical formation by ferrylmyoglobin...

Graphene oxide as a catalyst for the diastereoselective transfer hydrogenation in the synthesis of prostaglandin derivatives.

Science.gov (United States)

Coman, Simona M; Podolean, Iunia; Tudorache, Madalina; Cojocaru, Bogdan; Parvulescu, Vasile I; Puche, Marta; Garcia, Hermenegildo

2017-09-14

Modification of GO by organic molecules changes its catalytic activity in the hydrogen transfer from i-propanol to enones, affecting the selectivity to allyl alcohol and diastereoselectivity to the resulting stereoisomers. It is noteworthy the system does not contain metals and is recyclable.

Genetic modification and genetic determinism

Science.gov (United States)

Resnik, David B; Vorhaus, Daniel B

2006-01-01

In this article we examine four objections to the genetic modification of human beings: the freedom argument, the giftedness argument, the authenticity argument, and the uniqueness argument. We then demonstrate that each of these arguments against genetic modification assumes a strong version of genetic determinism. Since these strong deterministic assumptions are false, the arguments against genetic modification, which assume and depend upon these assumptions, are therefore unsound. Serious discussion of the morality of genetic modification, and the development of sound science policy, should be driven by arguments that address the actual consequences of genetic modification for individuals and society, not by ones propped up by false or misleading biological assumptions. PMID:16800884

Genetic modification and genetic determinism

Directory of Open Access Journals (Sweden)

Vorhaus Daniel B

2006-06-01

Full Text Available Abstract In this article we examine four objections to the genetic modification of human beings: the freedom argument, the giftedness argument, the authenticity argument, and the uniqueness argument. We then demonstrate that each of these arguments against genetic modification assumes a strong version of genetic determinism. Since these strong deterministic assumptions are false, the arguments against genetic modification, which assume and depend upon these assumptions, are therefore unsound. Serious discussion of the morality of genetic modification, and the development of sound science policy, should be driven by arguments that address the actual consequences of genetic modification for individuals and society, not by ones propped up by false or misleading biological assumptions.

An evaluation of the quantitative effects on radon gas from the modification of a home heating and air conditioning system

International Nuclear Information System (INIS)

Montague, A.

1991-01-01

The quantitative effects associated with the design, construction, operation, environmental and meteorological conditions on radon gas levels in a typical residential dwelling with a basement, having a measured radon level of approximately 20 pico-curies/liter (pCi/L), are evaluated. After several mechanical and electrical modifications are made on the dwelling's heating system, two different furnace breathing modes are studied. The effect on radon levels in the dwelling are observed as the furnace receives all of its combustion, draft and ventilation air - as the experiment alternates, on a bi-weekly basis - from inside and then outside the dwelling. Radon, barometric pressure, outside temperature, relative humidity, wind-speed and direction are monitored continuously; special household activity in the dwelling is also observed. A novel differential air pressure technique is used to measure inside versus outside house air pressure variations, twice each day, resulting from meteorological conditions, dwelling activity, and the furnace breathing mode. A rigorous statistical analysis is employed that includes sequential linear regression of time-series data, trend corrections to remove variations that contribute to the variance in the data without addition useful information. A novel approach using an electrical analog, to screen out unwanted variations is applied, by utilizing a computer routine to simulate the effect of an electronic RC filter, to achieve the desired analytical discrimination

From Coalgebra to Bialgebra for the Six-Vertex Model: The Star-Triangle Relation as a Necessary Condition for Commuting Transfer Matrices

Directory of Open Access Journals (Sweden)

Jeffrey R. Schmidt

2012-08-01

Full Text Available Using the most elementary methods and considerations, the solution of the star-triangle condition (a2+b2-c2/2ab = ((a’^2+(b’^2-(c’^2/2a’b’ is shown to be a necessary condition for the extension of the operator coalgebra of the six-vertex model to a bialgebra. A portion of the bialgebra acts as a spectrum-generating algebra for the algebraic Bethe ansatz, with which higher-dimensional representations of the bialgebra can be constructed. The star-triangle relation is proved to be necessary for the commutativity of the transfer matrices T(a, b, c and T(a’, b’, c’.

Printing-assisted surface modifications of patterned ultrafiltration membranes

International Nuclear Information System (INIS)

Wardrip, Nathaniel C.; Dsouza, Melissa; Urgun-Demirtas, Meltem; Snyder, Seth W.

2016-01-01

Understanding and restricting microbial surface attachment will enhance wastewater treatment with membranes. We report a maskless lithographic patterning technique for the generation of patterned polymer coatings on ultrafiltration membranes. Polyethylene glycol, zwitterionic, or negatively charged hydrophilic polymer compositions in parallel- or perpendicular-striped patterns with respect to feed flow were evaluated using wastewater. Membrane fouling was dependent on the orientation and chemical composition of the coatings. Modifications reduced alpha diversity in the attached microbial community (Shannon indices decreased from 2.63 to 1.89) which nevertheless increased with filtration time. Sphingomonas species, which condition membrane surfaces and facilitate cellular adhesion, were depleted in all modified membranes. Microbial community structure was significantly different between control, different patterns, and different chemistries. Lastly, this study broadens the tools for surface modification of membranes with polymer coatings and for understanding and optimization of antifouling surfaces.

Surface modification of ceramic and metallic alloy substrates by laser raster-scanning

Science.gov (United States)

Ramos Grez, Jorge Andres

This work describes the feasibility of continuous wave laser-raster scan-processing under controlled atmospheric conditions as employed in three distinct surface modification processes: (a) surface roughness reduction of indirect-Selective Laser Sintered 420 martensitic stainless steel-40 wt. % bronze infiltrated surfaces; (b) Si-Cr-Hf-C coating consolidation over 3D carbon-carbon composites cylinders; (c) dendritic solidification structures of Mar-M 247 confined powder precursor grown from polycrystalline Alloy 718 substrates. A heat transfer model was developed to illustrate that the aspect ratio of the laser scanned pattern and the density of scanning lines play a significant role in determining peak surface temperature, heating and cooling rates and melt resident times. Comprehensive characterization of the surface of the processed specimens was performed using scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), optical metallography, X-ray diffraction (XRD), and, in certain cases, tactile profilometry. In Process (a), it was observed that a 24% to 37% roughness Ra reduction could be accomplished from the as-received value of 2.50+/-0.10 microns for laser energy densities ranging from 350 to 500 J/cm2. In Process (b), complete reactive wetting of carbon-carbon composite cylinders surface was achieved by laser melting a Si-Cr-Hf-C slurry. Coatings showed good thermal stability at 1000°C in argon, and, when tested in air, a percent weight reduction rate of -6.5 wt.%/hr was achieved. A soda-glass overcoat applied over the coated specimens by conventional means revealed a percent weight reduction rate between -1.4 to -2.2 wt.%/hr. Finally, in Process (c), microstructure of the Mar-M 247 single layer deposits, 1 mm in height, grown on Alloy 718 polycrystalline sheets, resulted in a sound metallurgical bond, low porosity, and uniform thickness. Polycrystalline dendrites grew preferentially along the [001] direction from the substrate up to 400

The transferability of hydrological models under nonstationary climatic conditions

Directory of Open Access Journals (Sweden)

C. Z. Li

2012-04-01

Full Text Available This paper investigates issues involved in calibrating hydrological models against observed data when the aim of the modelling is to predict future runoff under different climatic conditions. To achieve this objective, we tested two hydrological models, DWBM and SIMHYD, using data from 30 unimpaired catchments in Australia which had at least 60 yr of daily precipitation, potential evapotranspiration (PET, and streamflow data. Nash-Sutcliffe efficiency (NSE, modified index of agreement (d₁ and water balance error (WBE were used as performance criteria. We used a differential split-sample test to split up the data into 120 sub-periods and 4 different climatic sub-periods in order to assess how well the calibrated model could be transferred different periods. For each catchment, the models were calibrated for one sub-period and validated on the other three. Monte Carlo simulation was used to explore parameter stability compared to historic climatic variability. The chi-square test was used to measure the relationship between the distribution of the parameters and hydroclimatic variability. The results showed that the performance of the two hydrological models differed and depended on the model calibration. We found that if a hydrological model is set up to simulate runoff for a wet climate scenario then it should be calibrated on a wet segment of the historic record, and similarly a dry segment should be used for a dry climate scenario. The Monte Carlo simulation provides an effective and pragmatic approach to explore uncertainty and equifinality in hydrological model parameters. Some parameters of the hydrological models are shown to be significantly more sensitive to the choice of calibration periods. Our findings support the idea that when using conceptual hydrological models to assess future climate change impacts, a differential split-sample test and Monte Carlo simulation should be used to quantify uncertainties due to

Biomaterials modification by ion beam

International Nuclear Information System (INIS)

Zhang Tonghe; Yi Zhongzhen; Zhang Xu; Wu Yuguang

2001-01-01

Ion beam technology is one of best ways for the modification of biomaterials. The results of ion beam modification of biomaterials are given. The method and results of improved biocompatibility are indicated by ion beam technology. The future development of ion beam modification of biomaterials is discussed

Surface modification of protein enhances encapsulation in chitosan nanoparticles

Science.gov (United States)

Koyani, Rina D.; Andrade, Mariana; Quester, Katrin; Gaytán, Paul; Huerta-Saquero, Alejandro; Vazquez-Duhalt, Rafael

2018-04-01

Chitosan nanoparticles have a huge potential as nanocarriers for environmental and biomedical purposes. Protein encapsulation in nano-sized chitosan provides protection against inactivation, proteolysis, and other alterations due to environmental conditions, as well as the possibility to be targeted to specific tissues by ligand functionalization. In this work, we demonstrate that the chemical modification of the protein surface enhances the protein loading in chitosan nanocarriers. Encapsulation of green fluorescent protein and the cytochrome P450 was studied. The increase of electrostatic interactions between the free amino groups of chitosan and the increased number of free carboxylic groups in the protein surface enhance the protein loading, protein retention, and, thus, the enzymatic activity of chitosan nanoparticles. The chemical modification of protein surface with malonic acid moieties reduced drastically the protein isoelectric point increasing the protein interaction with the polycationic biomaterial and chitosan. The chemical modification of protein does not alter the morphology of chitosan nanoparticles that showed an average diameter of 18 nm, spheroidal in shape, and smooth surfaced. The strategy of chemical modification of protein surface, shown here, is a simple and efficient technique to enhance the protein loading in chitosan nanoparticles. This technique could be used for other nanoparticles based on polycationic or polyanionic materials. The increase of protein loading improves, doubtless, the performance of protein-loaded chitosan nanoparticles for biotechnological and biomedical applications.

Heat transfer and critical heat flux in a asymmetrically heated tube helicoidal flow; Transfert thermique et flux critique dans un ecoulement helicoidal en tube chauffe asymetriquement

Energy Technology Data Exchange (ETDEWEB)

Boscary, J

1995-10-01

The design of plasma facing components is crucial for plasma performance in next fusion reactors. These elements will be submitted to very high heat flux. They will be actively water-cooled by swirl tubes in the subcooled boiling regime. High heat flux experiments were conducted in order to analyse the heat transfer and to evaluate the critical heat flux. Water-cooled mock-ups were one-side heated by an electron beam gun for different thermal-hydraulic conditions. The critical heat flux was detected by an original method based on the isotherm modification on the heated surface. The wall heat transfer law including forced convection and subcooled boiling regimes was established. Numerical calculations of the material heat transfer conduction allowed the non-homogeneous distribution of the wall temperature and of the wall heat flux to be evaluated. The critical heat flux value was defined as the wall maximum heat flux. A critical heat flux model based on the liquid sublayer dryout under a vapor blanket was established. A good agreement with test results was found. (author). 198 refs., 126 figs., 21 tabs.

Safety of modifications at nuclear power plants - the role of minor modifications and human and organisational factors

International Nuclear Information System (INIS)

2005-01-01

Operating experience repeatedly shows that changes and modifications at nuclear power plants (NPPs) may lead to safety significant events. At the same time, modifications are necessary to ensure a safe and economic functioning of the NPPs. To ensure safety in all plant configurations it is important that modification processes are given proper attention both by the utilities and the regulators. The operability, maintainability and testability of every modification should be thoroughly assessed from different points of view to ensure that no safety problems are introduced. The OECD/NEA Committee on Safety of Nuclear Installations (CSNI) has recently addressed the issue of modifications by organising a 'Workshop on Modifications at Nuclear Power Plants Operating Experience, Safety Significance and Role of Human Factors'. This workshop was undertaken as a joint effort of the Working Group on Operating Experience (WGOE) and the Special Experts Group on Human and Organisational Factors (SEGHOF), and it was held at the OECD Headquarters in Paris on October 6 to 8, 2003. The initiative to organise the workshop was taken by the WGOE and the SEGHOF based on findings from events and incidents due to modifications at nuclear power plants in the world and weaknesses experienced in modification processes. During the workshop, the WGOE focused on the theme of 'Minor Modifications and their Safety Significance', while the SEGHOF focused on the topic 'Human and Organisational Factors in NPP Modifications'. This report is based on material collected before the workshop, the workshop proceedings, discussions of the group of experts responsible for the arrangement of the workshop, and additional material collected by a consultant. The workshop was preceded by extensive preparations, which included collection of national surveys in response to questionnaires on modifications at the NPPs. Not all of these surveys were available at the workshop, but their findings have now been included

Modification of JRR-2

International Nuclear Information System (INIS)

Miyasaka, Yasuhiko

1978-01-01

This report gives an outline of some of the main modifications carried out around the Reactor Core on the Research Reactor JRR-2, at the Tokai Research Establishment of JAERI. The JRR-2 was shut down in December 1973, to improve it in heavy water leakage from the metal packing between core tank and support ring, corrosion of the lower shielding plug, and fault in the control-rod mechanism. Main modifications were a standing seal weld at the support ring to stop heavy water leakage, replacement of the reactor top shield and improvement of the helium system. The control-rod assemblies and the refueling devices were replaced by the newly designed ones also. In addition to the modification plan, the irradiated air exhaust system was improved to reduce radioactive argon gas release through the stack. Works were completed successfully in September 1975. But a light water leakage occurred at the stand pipe below the light water tank on November 11, 1975, which was repaired in about 4 months. When considering the operation of above 5,000 hours after the modification, however, the quality of the modification work may be said to be quite satisfactory. The present report in which works to the completion are described may be valuable as a record of reactor modification which is a new experience at JAERI. (auth.)

Modification Propagation in Complex Networks

Science.gov (United States)

Mouronte, Mary Luz; Vargas, María Luisa; Moyano, Luis Gregorio; Algarra, Francisco Javier García; Del Pozo, Luis Salvador

To keep up with rapidly changing conditions, business systems and their associated networks are growing increasingly intricate as never before. By doing this, network management and operation costs not only rise, but are difficult even to measure. This fact must be regarded as a major constraint to system optimization initiatives, as well as a setback to derived economic benefits. In this work we introduce a simple model in order to estimate the relative cost associated to modification propagation in complex architectures. Our model can be used to anticipate costs caused by network evolution, as well as for planning and evaluating future architecture development while providing benefit optimization.

75 FR 49536 - Petitions for Modification of Existing Mandatory Safety Standards

Science.gov (United States)

2010-08-13

... wells utilizing the following terms and conditions: 1. District Manager Approval; (a) a safety barrier.... After District Manager approval, the mine operator will then mine within the safety barrier of the well... DEPARTMENT OF LABOR Mine Safety and Health Administration Petitions for Modification of Existing...

Comparison of tubeside condensation and evaporation characteristics of smooth and enhanced heat transfer 1EHT tubes

International Nuclear Information System (INIS)

Kukulka, David J.; Smith, Rick; Li, Wei

2015-01-01

Results are presented here from an experimental investigation that was performed to evaluate the inside condensation and evaporation heat transfer of R410A, R22 and R32 that took place in a 12.7 mm (0.5 in) O.D. horizontal copper tube at low mass fluxes. Tubes considered in this evaluation consisted of a smooth tube (inner diameter 11.43 mm) and a newly developed enhanced surface Vipertex™ 1EHT tube. Heat transfer enhancement is an important factor in obtaining energy efficiency improvements in a variety of heat transfer applications. Utilization of enhanced heat transfer tubes is often utilized in the development of high performance air conditioning and refrigeration systems. Vipertex™ has designed and produced these surfaces through three dimensional material surface modifications which produces flow optimized, enhanced heat transfer tubes that increase heat transfer. Heat transfer enhancement plays an important role in improving energy efficiencies and developing high performance thermal systems. This study details the evaluation of the in-tube evaporation and condensation that takes place in these tubes over a wide range of conditions. The test apparatus utilized included a straight horizontal test section with an active length heated by water circulated in the surrounding annulus. Constant heat flux was maintained and refrigerant quality varied. In-tube evaporation measurements of R22, R32 and R410A are reported for evaporation at 10 °C with mass flow rates in the range of 15–40 kg h"−"1. Single phase measurements are reported for mass flow rates from 15 kg h"−"1 to 80 kg h"−"1. Condensation tests were conducted at a saturation temperature of 47 °C, with an inlet quality of 0.8 and an outlet quality of 0.1. In a comparison to smooth tubes, the average heat transfer coefficients for the Vipertex 1EHT tube exceeded those of a smooth tube. Average evaporation and condensation heat transfer coefficients for R22, R32 and R410A in the 1EHT

Asymmetrical transfer effects of cognitive bias modification: Modifying attention to threat influences interpretation of emotional ambiguity, but not vice versa.

Science.gov (United States)

Bowler, J O; Hoppitt, L; Illingworth, J; Dalgleish, T; Ononaiye, M; Perez-Olivas, G; Mackintosh, B

2017-03-01

It is well established that attention bias and interpretation bias each have a key role in the development and continuation of anxiety. How the biases may interact with one another in anxiety is, however, poorly understood. Using cognitive bias modification techniques, the present study examined whether training a more positive interpretation bias or attention bias resulted in transfer of effects to the untrained cognitive domain. Differences in anxiety reactivity to a real-world stressor were also assessed. Ninety-seven first year undergraduates who had self-reported anxiety were allocated to one of four groups: attention bias training (n = 24), interpretation bias training (n = 26), control task training (n = 25) and no training (n = 22). Training was computer-based and comprised eight sessions over four weeks. Baseline and follow-up measures of attention and interpretation bias, anxiety and depression were taken. A significant reduction in threat-related attention bias and an increase in positive interpretation bias occurred in the attention bias training group. The interpretation bias training group did not exhibit a significant change in attention bias, only interpretation bias. The effect of attention bias training on interpretation bias was significant as compared with the two control groups. There were no effects on self-report measures. The extent to which interpretive training can modify attentional processing remains unclear. Findings support the idea that attentional training might have broad cognitive consequences, impacting downstream on interpretive bias. However, they do not fully support a common mechanism hypothesis, as interpretive training did not impact on attentional bias. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Transferência condicionada de renda e segurança alimentar e nutricional Conditional cash transfer programs and food and nutrition security

Directory of Open Access Journals (Sweden)

Luciene Burlandy

2007-12-01

Full Text Available Este artigo analisa as interações entre programas de transferência condicionada de renda (TCR e a segurança alimentar e nutricional (SAN, a partir de uma revisão da literatura. Considera que a TCR impacta os gastos com alimentação, especialmente quando há dinamismo de mercado e os investimentos com outros bens que afetam o bem- estar nutricional das famílias, incluindo a demanda por educação e cuidados com a saúde. No entanto, o impacto no estado nutricional, especialmente no crescimento infantil, não é inequívoco, pois depende de outras ações que afetam este processo, tais como a disponibilidade de serviços de saúde; educação; saneamento; os custos das famílias para acessá-los; o tempo de implementação dos programas; o valor transferido; o tamanho das famílias, além das regras intrafamiliares de alocação de recursos. De igual modo, cabe analisar o processo de implementação dos programas uma vez que podem afetar (positiva ou negativamente os valores, relações e práticas sociais que contribuem para a conformação da pobreza e da SAN. A integração da TCR com outros programas é essencial para garantir seu impacto na SAN e o atual Conselho Nacional de Segurança Alimentar e Nutricional constitui espaço estratégico para o planejamento integrado de políticas neste campo.This paper analyses the relationship between Conditional Cash Transfer (CCT programs and Food and Nutrition Security (FNS, based on a review of the literature. CCT programs spur outlays on food, particularly in dynamic markets, as well as investments in other goods affecting the nutritional wellbeing of families, including demands for healthcare and education. However, the impact on children's nutritional status and early childhood growth is not clear, as other factors also affect this process, such as: the availability of public services (healthcare; education; sanitation and the costs of accessing them; duration of the programs; transfer

Surface modification by preparation of buffer zone in glow-discharge plasma

International Nuclear Information System (INIS)

Cho, D.L.

1986-01-01

Reactive species, energetic particles, and uv radiation in the plasma created by a glow discharge strongly interact with solid surfaces under the influence of the plasma. As a result of the strong interaction, various physical and chemical reactions, unique and advantageous for the surface modification of solid materials, occur on the solid surfaces. The surface modification is carried out through formation of a thin buffering layer on the solid surface. The preparation of a buffer zone on solid surfaces for surface modification is described. Two kinds of a buffer zone are prepared by plasma polymerization, or simultaneous sputter deposition of electrode material with plasma polymerization: a transitional buffer zone and a graded buffer zone. Important factors for preparation of the buffer zone (pre-conditioning of a substrate surface, thin-film deposition, post-treatment of the film, magnetron discharge, energy input, geometry of a substrate and a plasma) are discussed

Enhancement of heat transfer rate with structural modification of double pipe heat exchanger by changing cylindrical form of tubes into conical form

International Nuclear Information System (INIS)

Hashemian, Mehran; Jafarmadar, Samad; Nasiri, Javid; Sadighi Dizaji, Hamed

2017-01-01

Highlights: • An improved geometry is presented by changing tubes form into conical. • Enhancement of heat transfer rate is investigated. • Frictional characteristics for novel geometry are studied. • For a proper understanding of the subject, the exact physical interpretation is added. • The effect of flow, geometry and thermodynamic parameters is considered. - Abstract: In this paper, cylindrical tubes of a double pipe heat exchanger were changed into the conical tubes as an innovative design which causes improvement of thermal performance of heat exchanger without increment of its weight. Utilization of conical tube instead of cylindrical tube can impress both thermal and frictional characteristics of heat exchanger. Hence, the effect of conical tubes on Nusselt number, friction factor and thermal performance factor are evaluated in present research which was not covered already. Moreover, the effects of hydrodynamic, thermodynamic and geometrical characteristics are analyzed. All said parameters are numerically investigated for nine different combinations of flow direction and conical tubes geometry. The results of simulations of the said configurations are presented to compare the cases from different points of view and determine the most thermally efficient case. The results reveal modified geometry makes 63% increment in Nu number and 54% increment in heat transfer rate at optimum condition.

Structural modifications under reactive atmosphere of cobalt catalysts; Modifications structurales sous atmospheres reactionnelles de catalyseurs a base de cobalt

Energy Technology Data Exchange (ETDEWEB)

Ducreux, O.

1999-11-23

The purpose of this work was to develop in situ methods under reactive dynamic conditions (XRD and Fourier transform infrared spectroscopy) to describe the active phase structure in order to understand Fischer-Tropsch catalyst behaviour and improve the natural gas conversion process performance. Experiments were designed to correlate structural modifications with catalytic results. The effect of ruthenium used as a promoter has also been studied. The impregnation process increases cobalt-support interaction. The presence of ruthenium promoter reduces this effect. Interactions between Co{sub 3}O{sub 4} oxide and support play an important role in the reducibility of cobalt and in the resulting metal structure. This in turn strongly influences the catalytic behaviour. Our results show a close correlation between structure modification and reactivity in the systems studied. Cobalt metal and CO can react to form a carbide Co{sub 2}C under conditions close to those of the Fischer-Tropsch synthesis. This carbide formation seems to be related to a deactivation process. The presence of interstitial carbon formed by dissociation of CO is proposed as a key to understanding the mechanism of the Fischer-Tropsch reaction. A specific catalyst activation treatment was developed to increase the catalytic activity. This work permits correlation of materials structure with their chemical properties and demonstrates the contribution of in situ physico-chemical characterisation methods to describe solids under reactive atmosphere. (author)

Heat transfer tests conducted on full-scale model, to investigate cooling conditions of EL.3 experimental reactor

International Nuclear Information System (INIS)

Raievski, R.; Bousquet, M.; Braudeau, M.; Milliat, M.

1958-01-01

For such high heat flux density as is released in the channels of EL3 reactor (2.10 6 kcal/m 2 h on the hottest point) cooling conditions have proved to be satisfactory, that is free from nucleate boiling. The arrangements provided for these tests and the technique used for measurements (of temperature particularly) are specified. Two fields have been investigated: in the former (forced convection without nucleate boiling) a good agreement is found with Colburn's formula. The influence of the ratio L/D is pointed out. The latter field is of forced convection with beginning of nucleate boiling; there the observed raise of the transfer coefficient has been shown occurring with some delay. (author) [fr

Fusion of GFP to the M.EcoKI DNA methyltransferase produces a new probe of Type I DNA restriction and modification enzymes

International Nuclear Information System (INIS)

Chen, Kai; Roberts, Gareth A.; Stephanou, Augoustinos S.; Cooper, Laurie P.; White, John H.; Dryden, David T.F.

2010-01-01

Research highlights: → Successful fusion of GFP to M.EcoKI DNA methyltransferase. → GFP located at C-terminal of sequence specificity subunit does not later enzyme activity. → FRET confirms structural model of M.EcoKI bound to DNA. -- Abstract: We describe the fusion of enhanced green fluorescent protein to the C-terminus of the HsdS DNA sequence-specificity subunit of the Type I DNA modification methyltransferase M.EcoKI. The fusion expresses well in vivo and assembles with the two HsdM modification subunits. The fusion protein functions as a sequence-specific DNA methyltransferase protecting DNA against digestion by the EcoKI restriction endonuclease. The purified enzyme shows Foerster resonance energy transfer to fluorescently-labelled DNA duplexes containing the target sequence and to fluorescently-labelled ocr protein, a DNA mimic that binds to the M.EcoKI enzyme. Distances determined from the energy transfer experiments corroborate the structural model of M.EcoKI.

Cross-Talk between Dnmt2-Dependent tRNA Methylation and Queuosine Modification

Directory of Open Access Journals (Sweden)

Ann E. Ehrenhofer-Murray

2017-02-01

Full Text Available Enzymes of the Dnmt2 family of methyltransferases have yielded a number of unexpected discoveries. The first surprise came more than ten years ago when it was realized that, rather than being DNA methyltransferases, Dnmt2 enzymes actually are transfer RNA (tRNA methyltransferases for cytosine-5 methylation, foremost C38 (m5C38 of tRNAAsp. The second unanticipated finding was our recent discovery of a nutritional regulation of Dnmt2 in the fission yeast Schizosaccharomyces pombe. Significantly, the presence of the nucleotide queuosine in tRNAAsp strongly stimulates Dnmt2 activity both in vivo and in vitro in S. pombe. Queuine, the respective base, is a hypermodified guanine analog that is synthesized from guanosine-5’-triphosphate (GTP by bacteria. Interestingly, most eukaryotes have queuosine in their tRNA. However, they cannot synthesize it themselves, but rather salvage it from food or from gut microbes. The queuine obtained from these sources comes from the breakdown of tRNAs, where the queuine ultimately was synthesized by bacteria. Queuine thus has been termed a micronutrient. This review summarizes the current knowledge of Dnmt2 methylation and queuosine modification with respect to translation as well as the organismal consequences of the absence of these modifications. Models for the functional cooperation between these modifications and its wider implications are discussed.

On the heat transfer correlation for membrane distillation

International Nuclear Information System (INIS)

Wang, Chi-Chuan

2011-01-01

Research highlights: → Heat transfer coefficients applicable for membrane distillation. → Data reduction for heat transfer coefficient for membrane distillation method. → Uncertainty of permeate side due to large magnitude of membrane resistance. → Increase accuracy of heat transfer coefficient by modified Wilson plot technique. -- Abstract: The present study examines the heat transfer coefficients applicable for membrane distillation. In the available literatures, researchers often adopt some existing correlations and claim the suitability of these correlations to their test data or models. Unfortunately this approach is quite limited and questionable. This is subject to the influences of boundary conditions, geometrical configurations, entry flow conditions, as well as some influences from spacer or support. The simple way is to obtain the heat transfer coefficients from experimentation. However there is no direct experimental data for heat transfer coefficients being reported directly from the measurements. The main reasons are from the uncertainty of permeate side and of the comparatively large magnitude of membrane resistance. Additional minor influence is the effect of mass transfer on the heat transfer performance. In practice, the mass transfer effect is negligible provided the feed side temperature is low. To increase the accuracy of the measured feed side heat transfer coefficient, it is proposed in this study to exploit a modified Wilson plot technique. Through this approach, one can eliminate the uncertainty from permeate side and reduce the uncertainty in membrane to obtain a more reliable heat transfer coefficients at feed side from the experimentation.

DAMPAK TRANSFER FISKAL (CONDITIONAL GRANT TERHADAP PEMBANGUNAN PERTANIAN, KEMISKINAN DAN KETIMPANGAN DI INDONESIA: ANALISIS DATA PANEL

Directory of Open Access Journals (Sweden)

Nor Qomariyah

2017-11-01

Full Text Available Kemiskinan menjadi permasalahan utama bangsa Indonesia, jumlah penduduk miskin sebesar 28.55 juta orang (11. 47%, sementara ketimpangan pendapatan meningkat hingga mencapai 0.41 (BPS, 2013. Penelitian ini bertujuan untuk mengevaluasi dampak Dana Alokasi Khusus (DAK yang berupa conditional grant terhadap pembangunan pertanian, kemiskinan, dan ketimpangan pendapatan. Penelitian ini menggunakan model persamaan simultan dengan data time series tahun 2009-2013 dan data cross section pada 11 provinsi di Indonesia. Metode untuk estimasi parameter menggunakan 2SLS. Hasil simulasi menunjukkan bahwa peningkatan alokasi DAK jalan dan irigasi dapat meningkatkan kinerja fiskal, sektor PDRB pertanian, total PDRB, dan total penyerapan tenaga kerja, tetapi penyerapan tenaga kerja sektor pertanian menurun disebabkan adanya kenaikan upah, menurunkan ketimpangan pendapatan dan mengurangi kemiskinan baik di daerah pedesaan maupun perkotaan. Penelitian ini merekomendasikan bahwa pemerintah pusat hendaknya meningkatkan injeksi dana langsung ke daerah lewat dana alokasi khusus (DAK bidang infrastruktur karena dampaknya efektif menurunkan kemiskinan.THE IMPACT OF FISCAL TRANSFER (CONDITIONAL GRANT ON AGRICULTURAL DEVELOPMENT, POVERTY AND INEQUALITY : PANEL ANALYSIS DATAABSTRACTPoverty is the main problem in Indonesia, the number of the poor is 28.55 million people (11.47%, while income inequality increased until 0.41 (BPS, 2013. The main objective of this study was to evaluate the impact of Special Allocation Fund on agricultural development, poverty, and income inequality. This study uses simultaneous equation models with time series data of 2009-2013 and cross section data of 11 provinces in Indonesia. Method for parameter estimation is 2SLS. The simulation results show that the increased allocation of DAK road and irrigation can increase fiscal performance, the agricultural sector GRDP, total GRDP, but the labour force absorbtion of agricultural decreases because of

Advanced Design Mixer Pump Tank 18 Design Modifications Summary Report

International Nuclear Information System (INIS)

Adkins, B.J.

2002-01-01

The Westinghouse Savannah River Company (WSRC) is preparing to retrieve high level waste (HLW) from Tank 18 in early FY03 to provide feed for the Defense Waste Processing Facility (DWPF) and to support tank closure in FY04. As part of the Tank 18 project, WSRC will install a single Advanced Design Mixer Pump (ADMP) in the center riser of Tank 18 to mobilize, suspend, and mix radioactive sludge in preparation for transfer to Tank 7. The use of a single ADMP is a change to the current baseline of four (4) standard slurry pumps used during previous waste retrieval campaigns. The ADMP was originally conceived by Hanford and supported by SRS to provide a more reliable and maintainable mixer pump for use throughout the DOE complex. The ADMP underwent an extensive test program at SRS between 1998 and 2002 to assess reliability and hydraulic performance. The ADMP ran for approximately 4,200 hours over the four-year period. A detailed tear down and inspection of the pump following the 4,2 00-hour run revealed that the gas mechanical seals and anti-friction bearings would need to be refurbished/replaced prior to deployment in Tank 18. Design modifications were also needed to meet current Authorization Basis safety requirements. This report documents the modifications made to the ADMP in support of Tank 18 deployment. This report meets the requirements of Tanks Focus Area (TFA) Milestone 3591.4-1, ''Issue Report on Modifications Made to the ADMP,'' contained in Technical Task Plan (TTP) SR16WT51, ''WSRC Retrieval and Closure.''

Advances in genetic modification of pluripotent stem cells.

Science.gov (United States)

Fontes, Andrew; Lakshmipathy, Uma

2013-11-15

Genetically engineered stem cells aid in dissecting basic cell function and are valuable tools for drug discovery, in vivo cell tracking, and gene therapy. Gene transfer into pluripotent stem cells has been a challenge due to their intrinsic feature of growing in clusters and hence not amenable to common gene delivery methods. Several advances have been made in the rapid assembly of DNA elements, optimization of culture conditions, and DNA delivery methods. This has lead to the development of viral and non-viral methods for transient or stable modification of cells, albeit with varying efficiencies. Most methods require selection and clonal expansion that demand prolonged culture and are not suited for cells with limited proliferative potential. Choosing the right platform based on preferred length, strength, and context of transgene expression is a critical step. Random integration of the transgene into the genome can be complicated due to silencing or altered regulation of expression due to genomic effects. An alternative to this are site-specific methods that target transgenes followed by screening to identify the genomic loci that support long-term expression with stem cell proliferation and differentiation. A highly precise and accurate editing of the genome driven by homology can be achieved using traditional methods as well as the newer technologies such as zinc finger nuclease, TAL effector nucleases and CRISPR. In this review, we summarize the different genetic engineering methods that have been successfully used to create modified embryonic and induced pluripotent stem cells. © 2013. Published by Elsevier Inc. All rights reserved.

Behavior Modification in Coaching.

Science.gov (United States)

Lynch, Annette Rutt; Stillman, Stephen M.

1979-01-01

An example of behavior modification used in athletic coaching is presented. The case study involves a member of a women's basketball team and details the use of behavior modification for both weight reduction and skill improvement. (JMF)

Defective APETALA2 Genes Lead to Sepal Modification in Brassica Crops

Science.gov (United States)

Zhang, Yanfeng; Huang, Shuhua; Wang, Xuefang; Liu, Jianwei; Guo, Xupeng; Mu, Jianxin; Tian, Jianhua; Wang, Xiaofeng

2018-01-01

Many vegetable and oilseed crops belong to Brassica species. The seed production of these crops is hampered often by abnormal floral organs, especially under the conditions of abiotic conditions. However, the molecular reasons for these abnormal floral organs remains poorly understood. Here, we report a novel pistil-like flower mutant of B. rapa. In the flower of this mutant, the four sepals are modified to one merged carpel that look like a ring in the sepal positions, enveloping some abnormal stamens and a pistil, and resulting in poor seed production. This novel mutant is named sepal-carpel modification (scm). DNA sequencing showed that the BrAP2a gene, the ortholog of Arabidopsis APETALA2 (AP2) that specifies sepal identity, losses the function of in scm mutant due to a 119-bp repeated sequence insertion that resulted in an early transcription termination. BrAP2b, the paralog of BrAP2a featured two single-nucleotide substitutions that cause a single amino acid substitution in the highly conserved acidic serine-rich transcriptional activation domain. Each of the two BrAP2 genes rescues the sepal defective phenotype of the ap2-5 mutant of Arabidopsis. Furthermore, the knockout mutation of the corresponding BnAP2 genes of oilseed rape (B. napus) by CRISPR/Cas9-mediated genome editing system resulted in scm-like phenotype. These results suggest that BrAP2 gene plays a key role in sepal modification. Our finding provides an insight into molecular mechanism underlying morphological modification of floral organs and is useful for genetic manipulation of flower modification and improvement of seed production of Brassica crops. PMID:29616073

Defective APETALA2 Genes Lead to Sepal Modification in Brassica Crops

Directory of Open Access Journals (Sweden)

Yanfeng Zhang

2018-03-01

Full Text Available Many vegetable and oilseed crops belong to Brassica species. The seed production of these crops is hampered often by abnormal floral organs, especially under the conditions of abiotic conditions. However, the molecular reasons for these abnormal floral organs remains poorly understood. Here, we report a novel pistil-like flower mutant of B. rapa. In the flower of this mutant, the four sepals are modified to one merged carpel that look like a ring in the sepal positions, enveloping some abnormal stamens and a pistil, and resulting in poor seed production. This novel mutant is named sepal-carpel modification (scm. DNA sequencing showed that the BrAP2a gene, the ortholog of Arabidopsis APETALA2 (AP2 that specifies sepal identity, losses the function of in scm mutant due to a 119-bp repeated sequence insertion that resulted in an early transcription termination. BrAP2b, the paralog of BrAP2a featured two single-nucleotide substitutions that cause a single amino acid substitution in the highly conserved acidic serine-rich transcriptional activation domain. Each of the two BrAP2 genes rescues the sepal defective phenotype of the ap2-5 mutant of Arabidopsis. Furthermore, the knockout mutation of the corresponding BnAP2 genes of oilseed rape (B. napus by CRISPR/Cas9-mediated genome editing system resulted in scm-like phenotype. These results suggest that BrAP2 gene plays a key role in sepal modification. Our finding provides an insight into molecular mechanism underlying morphological modification of floral organs and is useful for genetic manipulation of flower modification and improvement of seed production of Brassica crops.

Covalent electron transfer chemistry of graphene with diazonium salts.

Science.gov (United States)

Paulus, Geraldine L C; Wang, Qing Hua; Strano, Michael S

2013-01-15

Graphene is an atomically thin, two-dimensional allotrope of carbon with exceptionally high carrier mobilities, thermal conductivity, and mechanical strength. From a chemist's perspective, graphene can be regarded as a large polycyclic aromatic molecule and as a surface without a bulk contribution. Consequently, chemistries typically performed on organic molecules and surfaces have been used as starting points for the chemical functionalization of graphene. The motivations for chemical modification of graphene include changing its doping level, opening an electronic band gap, charge storage, chemical and biological sensing, making new composite materials, and the scale-up of solution-processable graphene. In this Account, we focus on graphene functionalization via electron transfer chemistries, in particular via reactions with aryl diazonium salts. Because electron transfer chemistries depend on the Fermi energy of graphene and the density of states of the reagents, the resulting reaction rate depends on the number of graphene layers, edge states, defects, atomic structure, and the electrostatic environment. We limit our Account to focus on pristine graphene over graphene oxide, because free electrons in the latter are already bound to oxygen-containing functionalities and the resulting chemistries are dominated by localized reactivity and defects. We describe the reaction mechanism of diazonium functionalization of graphene and show that the reaction conditions determine the relative degrees of chemisorption and physisorption, which allows for controlled modulation of the electronic properties of graphene. Finally we discuss different applications for graphene modified by this chemistry, including as an additive in polymer matrices, as biosensors when coupled with cells and biomolecules, and as catalysts when combined with nanoparticles.

Conditional cash transfer impact evaluation: an evaluation of the costa rican secondary education program Avancemos

Directory of Open Access Journals (Sweden)

Catherine Mata

2015-07-01

Full Text Available This paper evaluates the impact of Avancemos, a conditional cash transfer program in Costa Rica. Specifically, this paper measures the impact on student desertion for the first year of the program using a panel created with the Household Surveys for Multiple Purposes for the years 2006 and 2007, elaborated by the National Institute of Statistics and Census. Using econometric tools and quasi-experimental methodologies such as Propensity Score Matching and difference-in-differences, we find a positive impact associated to the program for desertion and reinsertion. Specifically, for between 10 and 16 percent of the students who did not leave high school, it was only due to Avancemos, meaning that without the program they would have abandoned their studies. This is why we can conclude that Avancemos had a positive impact according to its planned objectives of preventing dropouts and ensuring their reinsertion.

Finite element simulation of heat transfer

CERN Document Server

Bergheau, Jean-Michel

2010-01-01

This book introduces the finite element method applied to the resolution of industrial heat transfer problems. Starting from steady conduction, the method is gradually extended to transient regimes, to traditional non-linearities, and to convective phenomena. Coupled problems involving heat transfer are then presented. Three types of couplings are discussed: coupling through boundary conditions (such as radiative heat transfer in cavities), addition of state variables (such as metallurgical phase change), and coupling through partial differential equations (such as electrical phenomena).? A re

14 CFR 1260.69 - Electronic funds transfer payment methods.

Science.gov (United States)

2010-01-01

... Government by electronic funds transfer through the Treasury Fedline Payment System (FEDLINE) or the... 14 Aeronautics and Space 5 2010-01-01 2010-01-01 false Electronic funds transfer payment methods... COOPERATIVE AGREEMENTS General Special Conditions § 1260.69 Electronic funds transfer payment methods...

Surface modification of upconverting nanoparticles by layer-by-layer assembled polyelectrolytes and metal ions.

Science.gov (United States)

Palo, Emilia; Salomäki, Mikko; Lastusaari, Mika

2017-12-15

Modificating and protecting the upconversion luminescence nanoparticles is important for their potential in various applications. In this work we demonstrate successful coating of the nanoparticles by a simple layer-by-layer method using negatively charged polyelectrolytes and neodymium ions. The layer fabrication conditions such as number of the bilayers, solution concentrations and selected polyelectrolytes were studied to find the most suitable conditions for the process. The bilayers were characterized and the presence of the desired components was studied and confirmed by various methods. In addition, the upconversion luminescence of the bilayered nanoparticles was studied to see the effect of the surface modification on the overall intensity. It was observed that with selected deposition concentrations the bilayer successfully shielded the particle resulting in stronger upconversion luminescence. The layer-by-layer method offers multiple possibilities to control the bilayer growth even further and thus gives promises that the use of upconverting nanoparticles in applications could become even easier with less modification steps in the future. Copyright © 2017 Elsevier Inc. All rights reserved.

New surface modification method of bio-titanium alloy by EB polishing

International Nuclear Information System (INIS)

Okada, Akira; Uno, Yoshiyuki; Iio, Atsuo; Fujiwara, Kunihiko; Doi, Kenji

2008-01-01

A new surface modification for bio-titanium alloy products by electron beam (EB) polishing is proposed. In this EB polishing method, high energy density EB can be irradiated without concentrating the beam. Therefore, large-area EB with a maximum diameter of 60 mm can be used for instantaneously melting or evaporating metal surface. Experimental results made it clear that surface characteristics, such as repellency, corrosion resistance and coefficient of friction could be improved simultaneously with the surface smoothing in a few minutes under a proper condition. Therefore, EB polishing method has a possibility of high efficient surface smoothing and surface modification process for bio-titanium alloy. (author)

Fetal muscle gene transfer is not enhanced by an RGD capsid modification to high-capacity adenoviral vectors.

Science.gov (United States)

Bilbao, R; Reay, D P; Hughes, T; Biermann, V; Volpers, C; Goldberg, L; Bergelson, J; Kochanek, S; Clemens, P R

2003-10-01