Lasing cavities and ultra-fast switch based on self-collimation of photonic crystal

Energy Technology Data Exchange (ETDEWEB)

Zhao Deyin; Zhou Chuanhong; Gong Qian; Jiang Xunya [State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai 200050 (China)], E-mail: xyjiang@mit.edu

2008-06-07

The lasing cavities and ultra-fast switch based on the self-collimation (SC) of photonic crystal have been studied in this work. Some special properties of these devices are demonstrated, such as the higher quality factors and concise integration of the lasing cavities, the tolerance of the non-parallel reflectors in Fabry-Perot cavities. With nonlinearity, the ultra-fast switch can also be realized around the SC frequency. All these functional devices are designed based on the strong beam confinement of SC.

Design of large aperture 500 MHz 5-cell superconducting cavity

International Nuclear Information System (INIS)

Wei Yelong; Feng Ziqiang; Lu Changwang; Yu Haibo; Liu Jianfei; Hou Hongtao; Ma Zhenyu; Mao Dongqing

2012-01-01

With the potential application of Energy Recovery Linac (ERL), the superconducting (SC) cavities were developed to deliver much higher current than before. Nowadays, the current of the international SC accelerator designed has already exceeded 100 mA. This paper presents the design of a new 500 MHz 5-cell SC cavity (SINAP 5-cell cavity), in which the parameters r/Q= 515.5 Ω of the fundamental mode and the geometry factor G=275.8 are under an acceptable Radio Frequency (RF) field level. (B peak /E acc =4.31 mT/MV/m and E peak /E acc =2.48). This design employs a larger beam pipe to propagate the Higher Order Modes (HOMs) out of the cavity and increases the damping efficiently for the dangerous HOMs. By simulation technique, it has been found that almost all the dangerous HOMs (including TE 111 , TM 110 , and TM 011 ) can be propagated into the beam pipe and are absorbed by ferrite absorbers, when the beam pile is enlarged. Finally, the loss factor for the new 5-cell cavity is also calculated. (authors)

Quasiparticle Level Alignment for Photocatalytic Interfaces.

Science.gov (United States)

Migani, Annapaoala; Mowbray, Duncan J; Zhao, Jin; Petek, Hrvoje; Rubio, Angel

2014-05-13

Electronic level alignment at the interface between an adsorbed molecular layer and a semiconducting substrate determines the activity and efficiency of many photocatalytic materials. Standard density functional theory (DFT)-based methods have proven unable to provide a quantitative description of this level alignment. This requires a proper treatment of the anisotropic screening, necessitating the use of quasiparticle (QP) techniques. However, the computational complexity of QP algorithms has meant a quantitative description of interfacial levels has remained elusive. We provide a systematic study of a prototypical interface, bare and methanol-covered rutile TiO2(110) surfaces, to determine the type of many-body theory required to obtain an accurate description of the level alignment. This is accomplished via a direct comparison with metastable impact electron spectroscopy (MIES), ultraviolet photoelectron spectroscopy (UPS), and two-photon photoemission (2PP) spectroscopy. We consider GGA DFT, hybrid DFT, and G0W0, scQPGW1, scQPGW0, and scQPGW QP calculations. Our results demonstrate that G0W0, or our recently introduced scQPGW1 approach, are required to obtain the correct alignment of both the highest occupied and lowest unoccupied interfacial molecular levels (HOMO/LUMO). These calculations set a new standard in the interpretation of electronic structure probe experiments of complex organic molecule/semiconductor interfaces.

Development of a fast piezo-based frequency tuner for superconducting CH cavities

International Nuclear Information System (INIS)

Amberg, Michael

2015-01-01

In this thesis, a fast piezo-based frequency tuner for current and prospective superconducting (sc) CH-cavities has been developed. The novel tuning concept differs fundamentally from conventional tuning systems for superconducting cavities. So called dynamic bellow tuners are welded into the resonator to act against slow and fast frequency variations during operation. Because of their adjustable length it is possible to specifically influence the capacitance and therefore the resonance frequency of the cavity. To change the length of the dynamic bellow tuners the frequency tuner drive, which consists of a slow tuning device controlled by a stepper motor and a fast piezo-based tuning system, is mounted to the helium vessel of the cavity. To validate the whole tuning concept a frequency tuner drive prototype was built in the workshop of the Institute for Applied Physics (IAP) of Frankfurt University. First successful room temperature measurements show that the developed frequency tuning system is an excellent and promising candidate to fulfill the requirements of slow and fast frequency tuning of sc CH-cavities during operation. Furthermore, several coupled structural and electromagnetic simulations of the sc 325 MHz CH-cavity as well as the sc 217 MHz CH-cavity have been performed with the simulation softwares ANSYS Workbench and CST MicroWave Studio, respectively. With these simulations it was possible to reduce the required frequency range and thus the mechanical stroke of the dynamic bellow tuners on the one hand, and on the other hand the mechanical stability of the particular CH-cavity was investigated to avoid plastic deformations due to limiting external effects. To verify the accuracy of the coupled simulations the structural mechanical behaviour and the resulting frequency variations of the sc CH-cavities dependent on the external influences were measured at room temperature as well as at cryogenic temperatures around 4.2 K. The measurement results of both

Low- to medium-β cavities for heavy ion acceleration

Science.gov (United States)

Facco, Alberto

2017-02-01

Acceleration of low- and medium-β heavy ions by means of superconducting (SC) linear accelerators (linacs) was made possible by the development, during four decades, of a particular class of cavities characterized by low operation frequency, several different shapes and different electromagnetic modes of operation. Their performance, initially rather poor in operating accelerators, have steadily increased along with the technological progress and nowadays the gap with the high-β, elliptical cavities is close to be filled. Initially confined to a very small number of applications, this family of cavities evolved in many directions becoming one of the most widespread in linacs. Nowadays it is present in the majority of superconducting radio-frequency ion linac projects worldwide. An overview of low- and medium-β SC cavities for heavy ions, focused on their recent evolution and achievements, will be given.

A High Current Proton Linac with 352 MHz SC Cavities

CERN Document Server

Pagani, C; Pierini, P

1996-01-01

A proposal for a 10-120 mA proton linac employing superconducting beta-graded, CERN type, four cell cavities at 352 MHz is presented. The high energy part (100 MeV-1 GeV) of the machine is split in three beta-graded sections, and transverse focusing is provided via a periodic doublet array. All the parameters, like power in the couplers and accelerating fields in the cavities, are within the state of the art, achieved in operating machines. A first stage of operation at 30 mA beam current is proposed, while the upgrade of the machine to 120 mA operation can be obtained increasing the number of klystrons and couplers per cavity. The additional coupler ports, up to four, will be integrated in the cavity design. Preliminary calculations indicate that beam transport is feasible, given the wide aperture of the 352 MHz structures. A capital cost of less than 100 M$ at 10 mA, reaching up to 280 M$ for the 120 mA extension, has been estimated for the superconducting high energy section (100 MeV-1 GeV). The high effic...

Magnetic alignment of SWCNTs decorated with Fe3O4 to enhance mechanical properties of SC-15 epoxy

Directory of Open Access Journals (Sweden)

O. Malkina

2013-04-01

Full Text Available We report significant improvement in mechanical properties of SC-15 epoxy when reinforced with decorated nanotubes and cured in a modest magnetic field. The chemical synthesis and field curing process is a low cost and relatively easy technique to impose strong magnetic anisotropy into the system without the need of a superconducting magnet. SWCNT(COOHs were decorated with Fe3O4 nanoparticles through a sonochemical oxidation process and then dispersed into SC-15 epoxy at 0.5 wt% loading. The admixture was cured for 6 hours in a magnetic field of 10 kOe followed by an additional 24 hours of post curing at room temperature. Control samples were prepared in a similar manner but without the application of the magnetic field. Mechanical tests performed on field-cured samples indicated that tensile strength and modulus increased by 62% and 40%. Most importantly, modulus of toughness, fracture strain, and modulus of resilience improved by 346%, 165%% and 170%, respectively. Such enhancement in mechanical properties was attributed to changes in polymer morphology, partial alignment of nanotubes in the field direction, and sliding at the polymer-nanotube interface. Detailed characterization of the system with XRD, TEM, DMA, and Magnetometry are described in the paper.

CLIC crab cavity design optimisation for maximum luminosity

Energy Technology Data Exchange (ETDEWEB)

Dexter, A.C., E-mail: a.dexter@lancaster.ac.uk [Lancaster University, Lancaster, LA1 4YR (United Kingdom); Cockcroft Institute, Daresbury, Warrington, WA4 4AD (United Kingdom); Burt, G.; Ambattu, P.K. [Lancaster University, Lancaster, LA1 4YR (United Kingdom); Cockcroft Institute, Daresbury, Warrington, WA4 4AD (United Kingdom); Dolgashev, V. [SLAC, Menlo Park, CA 94025 (United States); Jones, R. [University of Manchester, Manchester, M13 9PL (United Kingdom)

2011-11-21

The bunch size and crossing angle planned for CERN's compact linear collider CLIC dictate that crab cavities on opposing linacs will be needed to rotate bunches of particles into alignment at the interaction point if the desired luminosity is to be achieved. Wakefield effects, RF phase errors between crab cavities on opposing linacs and unpredictable beam loading can each act to reduce luminosity below that anticipated for bunches colliding in perfect alignment. Unlike acceleration cavities, which are normally optimised for gradient, crab cavities must be optimised primarily for luminosity. Accepting the crab cavity technology choice of a 12 GHz, normal conducting, travelling wave structure as explained in the text, this paper develops an analytical approach to optimise cell number and iris diameter.

Application of International Linear Collider superconducting cavities for acceleration of protons

Directory of Open Access Journals (Sweden)

P. N. Ostroumov

2007-12-01

Full Text Available Beam acceleration in the International Linear Collider (ILC will be provided by 9-cell 1300 MHz superconducting (SC cavities. The cavities are designed for effective acceleration of charged particles moving with the speed of light and are operated on π-mode to provide a maximum accelerating gradient. A significant research and development effort has been devoted to develop ILC SC technology and its rf system which resulted in excellent performance of ILC cavities. Therefore, the proposed 8-GeV proton driver in Fermilab is based on ILC cavities above ∼1.2  GeV. The efficiency of proton beam acceleration by ILC cavities drops fast for lower velocities and it was proposed to develop squeezed ILC-type (S-ILC cavities operating at 1300 MHz and designed for β_{G}=0.81, geometrical beta, to accelerate protons or H^{-} from ∼420  MeV to 1.2 GeV. This paper discusses the possibility of avoiding the development of new β_{G}=0.81 cavities by operating ILC cavities on 8/9π-mode of standing wave oscillations.

Development of manufacturing methods using hydroforming for superconducting cavities

International Nuclear Information System (INIS)

Ohara, K.; Shibuya, J.; Ota, T.; Takaishi, K.; Onishi, Y.; Saito, K.; Fujino, T.; Inoue, H.

2000-01-01

To obtain a higher field gradient, the profile of half-cell cavities must correspond with the optimized shape obtained by calculation. SC cavities are fabricated from sheet material by deep drawing of cavity half-cells and electron beam welding. A fabrication technique without the need of welding would substantially reduce fabrication costs and eliminate defects caused by the welding process. In this study, hydroforming was performed on Cu pipes instead of Nb ones to obtain seamless cavities. After this experiment, the inner profiles of cavities were measured by a coordinate measuring machine and evaluated. (author)

Development of manufacturing methods using hydroforming for superconducting cavities

Energy Technology Data Exchange (ETDEWEB)

Ohara, K.; Shibuya, J.; Ota, T.; Takaishi, K.; Onishi, Y. [Toshiba Corp., Yokohama, Kanagawa (Japan); Saito, K.; Fujino, T.; Inoue, H. [High Energy Accelerator Research Organization, Tsukuba, Ibaraki (Japan)

2000-02-01

To obtain a higher field gradient, the profile of half-cell cavities must correspond with the optimized shape obtained by calculation. SC cavities are fabricated from sheet material by deep drawing of cavity half-cells and electron beam welding. A fabrication technique without the need of welding would substantially reduce fabrication costs and eliminate defects caused by the welding process. In this study, hydroforming was performed on Cu pipes instead of Nb ones to obtain seamless cavities. After this experiment, the inner profiles of cavities were measured by a coordinate measuring machine and evaluated. (author)

The influence of chemical treatments on the superconducting properties of technical niobium materials and their effect on the performance of superconducting radio frequency cavities

International Nuclear Information System (INIS)

Roy, S B; Sahni, V C; Myneni, G R

2009-01-01

We present the results of a study of superconducting response in the niobium materials used in the fabrication of high accelerating gradient (>25 MV m -1 ) superconducting radio frequency (SC-RF) cavities. These results clearly show that the typical surface chemical treatment deployed during the fabrication of SC-RF cavities affects the superconducting properties of pure niobium materials. Such SC-RF cavities operating at 2 K are often found to show anomalous RF losses, causing either a strong degradation of the quality factor or a thermal breakdown for cavity magnetic fields between 1 and 1.5 kOe. The results of our study suggest a correlation between the field for the first flux-line penetration in these chemically treated technical niobium materials and the reported onset field of anomalous losses in the SC-RF cavities.

The influence of chemical treatments on the superconducting properties of technical niobium materials and their effect on the performance of superconducting radio frequency cavities

Science.gov (United States)

Roy, S. B.; Myneni, G. R.; Sahni, V. C.

2009-10-01

We present the results of a study of superconducting response in the niobium materials used in the fabrication of high accelerating gradient (>25 MV m-1) superconducting radio frequency (SC-RF) cavities. These results clearly show that the typical surface chemical treatment deployed during the fabrication of SC-RF cavities affects the superconducting properties of pure niobium materials. Such SC-RF cavities operating at 2 K are often found to show anomalous RF losses, causing either a strong degradation of the quality factor or a thermal breakdown for cavity magnetic fields between 1 and 1.5 kOe. The results of our study suggest a correlation between the field for the first flux-line penetration in these chemically treated technical niobium materials and the reported onset field of anomalous losses in the SC-RF cavities.

Crab cavities for linear colliders

CERN Document Server

Burt, G; Carter, R; Dexter, A; Tahir, I; Beard, C; Dykes, M; Goudket, P; Kalinin, A; Ma, L; McIntosh, P; Shulte, D; Jones, Roger M; Bellantoni, L; Chase, B; Church, M; Khabouline, T; Latina, A; Adolphsen, C; Li, Z; Seryi, Andrei; Xiao, L

2008-01-01

Crab cavities have been proposed for a wide number of accelerators and interest in crab cavities has recently increased after the successful operation of a pair of crab cavities in KEK-B. In particular crab cavities are required for both the ILC and CLIC linear colliders for bunch alignment. Consideration of bunch structure and size constraints favour a 3.9 GHz superconducting, multi-cell cavity as the solution for ILC, whilst bunch structure and beam-loading considerations suggest an X-band copper travelling wave structure for CLIC. These two cavity solutions are very different in design but share complex design issues. Phase stabilisation, beam loading, wakefields and mode damping are fundamental issues for these crab cavities. Requirements and potential design solutions will be discussed for both colliders.

Superconducting Radio-Frequency Cavities for Low-Beta Particle Accelerators

Science.gov (United States)

Kelly, Michael

2012-01-01

High-power proton and ion linac projects based on superconducting accelerating cavities are driving a worldwide effort to develop and build superconducting cavities for beta < 1. Laboratories and institutions building quarter-wave, halfwave and single- or multi-spoke cavities continue to advance the state of the art for this class of cavities, and the common notion that low-beta SRF cavities fill a need in niche applications and have low performance is clearly no longer valid. This article reviews recent developments and results for SC cavity performance for cavities with beta up to approximately 0.5. The considerable ongoing effort on reduced beta elliptical cell cavities is not discussed. An overview of associated subsystems required to operate low-beta cavities, including rf power couplers and fast and slow tuners, is presented.

Progress in diagnostic techniques for SC [superconducting] cavities

International Nuclear Information System (INIS)

Reece, C.E.

1988-01-01

Despite the very real progress that has been made, the routine performance of superconducting cavities still falls far short of both the theoretical expectations and the performance of afew exceptional examples. It is the task of systematically applied diagnostic techniques to reveal additional information concerning the response of superconducting surfaces to applied RF fields. In this paper we will direct our attention to discussions of recent developments in diagnostic techniqeus, such as thermometry in superfluid helium, and scanning laser acoustic microscopy. 18 refs., 12 figs

Gain-assisted broadband ring cavity enhanced spectroscopy

Science.gov (United States)

Selim, Mahmoud A.; Adib, George A.; Sabry, Yasser M.; Khalil, Diaa

2017-02-01

Incoherent broadband cavity enhanced spectroscopy can significantly increase the effective path length of light-matter interaction to detect weak absorption lines over broad spectral range, for instance to detect gases in confined environments. Broadband cavity enhancement can be based on the decay time or the intensity drop technique. Decay time measurement is based on using tunable laser source that is expensive and suffers from long scan time. Intensity dependent measurement is usually reported based on broadband source using Fabry-Perot cavity, enabling short measurement time but suffers from the alignment tolerance of the cavity and the cavity insertion loss. In this work we overcome these challenges by using an alignment-free ring cavity made of an optical fiber loop and a directional coupler, while having a gain medium pumped below the lasing threshold to improve the finesse and reduce the insertion loss. Acetylene (C2H2) gas absorption is measured around 1535 nm wavelength using a semiconductor optical amplifier (SOA) gain medium. The system is analyzed for different ring resonator forward coupling coefficient and loses, including the 3-cm long gas cell insertion loss and fiber connector losses used in the experimental verification. The experimental results are obtained for a coupler ratio of 90/10 and a fiber length of 4 m. The broadband source is the amplified spontaneous emission of another SOA and the output is measured using a 70pm-resolution optical spectrum analyzer. The absorption depth and the effective interaction length are improved about an order of magnitude compared to the direct absorption of the gas cell. The presented technique provides an engineering method to improve the finesse and, consequently the effective length, while relaxing the technological constraints on the high reflectivity mirrors and free-space cavity alignment.

Superconducting cavities for beauty factories

International Nuclear Information System (INIS)

Lengeler, H.

1992-01-01

The possibilities and merits of superconducting accelerating cavities for Beauty-factories are considered. There exist already large sc systems of size and frequency comparable to the ones needed for Beauty-factories. Their status and operation experience is discussed. A comparison of normal conducting and superconducting systems is done for two typical Beauty-factory rings

Results of SC proton cavity tests (B = 1 and B = 0.65)

CERN Document Server

Peauger, F et al

2013-01-01

The two superconducting cavities were carefully designed for challenging performance. They were fabricated in industry with intermediate tests and specialized processing in CEA and CNRS. The results are promising, except for a degradation of the field flatness of the low velocity cavity, after electron-beam welding. This might reduce the accelerating gradient. Due to delays in manufacturing, the final performance tests will be carried out in the coming months.

Time resolved super continuum Cavity Ring-Down Spectroscopy for multicomponent gas detection

International Nuclear Information System (INIS)

Nakaema, Walter Morinobu

2010-01-01

In this work, we present a variation of the technique CRDS (Cavity Ring-Down Spectroscopy) to obtain simultaneously a multicomponent absorption spectrum in a broad visible range. This new approach uses the Supercontinuum (SC) spectrum (resulting from irradiation of nonlinear media by femtosecond lasers, or simply generated by compact sources) as a light source to illuminate the cavity. In this context it is described the features of the modules assembling a MC-SC-CRDS (Multicomponent Supercontinuum Cavity Ring-Down Spectroscopy): a set of high reflectivity mirrors, the resonant cavity and the detection system. Some problems related to the multimode excitation, stray light, effective use of the dynamic range of the detector, the poor resolution of the instrument to resolve narrow absorption lines are issued. We present the absorption spectra of H 2 O (polyads 4υ, 4υ + δ) and O 2 (spin-forbidden b-X branch) measured simultaneously by this technique in the visible range and a comparison with the absorption lines based on HITRAN database is made to demonstrate the functionality of this method. (author)

Compact intra-cavity pumped low-threshold passively Q-switched Ho:Sc2SiO5 laser by a LD-pumped Tm:YAP laser at room temperature

Science.gov (United States)

Yang, Xiao-tao; Xie, Wen-qiang; Liu, Long; Li, Lin-jun

2017-08-01

A compact intra-cavity pumped low-threshold passively Q-switched (PQS) Ho:Sc2SiO5 (Ho:SSO) laser is reported for the first time. The Tm:YAlO3 (Tm:YAP) crystal and the Ho:SSO crystal are placed in the same laser cavity. A laser diode with a central wavelength of 793 nm is used to realize the output of the Ho:SSO laser. Both the continuous wave (CW) and PQS operation are investigated. A Cr2+:ZnSe is used as the saturable absorber in the PQS Ho:SSO laser. For the CW mode, the laser threshold is only 750 mW, which is 980 mW in the PQS mode. A maximum pulse energy of 699 µJ is primarily obtained, corresponding to the pulse width of 96 ns. The maximum repetition frequency is 1.46 kHz. The maximum pulse peak power can be calculated to be 7.28 kW. The beam quality factor M 2 is calculated to be 1.4 with the maximum output power.

Industrial production of SC RF accelerating cavities at CERCA. Latest results

International Nuclear Information System (INIS)

Boutes, J.L.; Maccioni, P.

1996-01-01

CERCA is one of the most experienced companies throughout the world for the manufacture of superconducting RF accelerating devices. The latest results obtained during the past 2 years on CERCA's superconducting cavities are presented. (K.A.)

Figure 1. Prediction of ScHP1 transmembrane domains I to XIV. (http ...

Indian Academy of Sciences (India)

Figure 2. Comparison of the ScHP1 amino acid sequence with H. +. -PPase from other species. The conserved domains GGG,. DVGADLVGKVE, DNVGDNVGD, EYYT and GNTTAA were found in the sequence alignment (shown in red boxes).

Primary beam-loading tests on DC-SC photoinjector at Peking University

International Nuclear Information System (INIS)

Hao Jiankui; Lu Xiangyang; Ding, Yuantao; Quan Shengwen; Huang Senlin; Zhao Kui; Zhang Baocheng; Wang Lifang; Lin Lin; Jiao Fei; Wang Guimei; Xie Datao; Zhu Feng; Xiao Binping; Xiang Rong; Chen Jia'er

2006-01-01

The DC-SC photoinjector is a compact electron gun integrating a DC pierce gun with a 1.3 GHz 1+1/2 cell superconducting cavity. A test facility of the DC-SC photoinjector had been installed in Peking University and beam-loading tests at 4.4 K have been finished. To date the gradient of 6 MV/m has been achieved. The maximum energy gain is 1.1 MeV at 4.4 K. With average beam current of 270 μA, the measured rms emittance is about 5 mm mrad at the beam energy of 500 keV. In this paper some of the experimental results are summarized

Anticrab cavities for the removal of spurious vertical bunch rotations caused by crab cavities

Directory of Open Access Journals (Sweden)

G. Burt

2008-09-01

Full Text Available Many particle accelerators are proposing the use of crab cavities to correct for accelerator crossing angles or for the production of short bunches in light sources. These cavities produce a rotation to the bunch in a well-defined polarization plane. If the plane of the rotation does not align with the horizontal axis of the accelerator, the bunch will receive a small amount of spurious vertical bunch rotation. For accelerators with small vertical beam sizes and large beam-beam effects, this can cause significant unwanted effects. In this paper we propose the use of a 2nd smaller crab cavity in the vertical plane in order to cancel this effect and investigate its use in numerical simulations.

Overview of electrical axis measurement in TESLA-type cavities

International Nuclear Information System (INIS)

Labanc, Anton

2007-01-01

The cells of TESLA cavities are mechanically aligned and tuned before the cavities are installed into the cryomodule. The alignment minimizes unwanted interaction of the accelerated beam with the transverse electric field component and the magnetic field of the accelerating TM 010 -π mode. It also reduces an interaction with higher order modes. The tuning equalizes field amplitudes of the accelerating mode in all cells. Until now, the eccentricity (misalignment) of cells is measured mechanically with residual misalignment after tuning up to 0.4 mm. Unfortunately the mechanical measurement is only weakly related to the electromagnetic fields inside a cavity, both for the accelerating and higher order modes. For improvement of the precision a new method of electromagnetic field mapping inside a cavity, based on small perturbation theory was developed. This method can be applied to modes which do not propagate through the beam pipes. In the setup built for the axis measurement a metallic needle is used as field perturbing object. Conducted tests confirmed high precision of 0.1 mm. Tests on the copper model for which it is possible to excite all of considered modes and on several niobium cavities were performed. In this paper an overview of measurement method, equipment and first results are reported. (orig.)

Study of a spoke cavity for low-beta applications

International Nuclear Information System (INIS)

Olry, G.; Biarrotte, J.L.; Saugnac, H.; Lesrel, J.

2003-01-01

Since a few years, intensive studies have been developed on SC cavities (for instance, spoke-type or reentrant cavities) for their use as accelerating structures in the low energy part of high power proton or ions accelerators (typically from 5 to 100 MeV). Within the framework of the EURISOL (EURopean Isotope Separation On-Line) and XADS (eXperimental Accelerator Driven System) European accelerators projects, IPN Orsay decided to plan a R and D program on low-beta spoke-type cavities. In the major part of this paper, we report on the optimization of the geometry of a β=0.35, 2 gap spoke cavity, aiming at achieving good electromagnetic parameters (i.e. lowest E pk /E acc and B pk /E acc ). A mechanical study is also presented, as well as a preliminary design of a proton spoke Linac (12-85 MeV) composed of β=0.18 and β=0.35, 2 gap cavities. (author)

Dynamics of a broad-area diode laser with lateral-mode-selected long-cavity feedback

DEFF Research Database (Denmark)

Chi, Mingjun; Petersen, Paul Michael

2014-01-01

The temporal dynamics of a broad-area diode laser with lateral-mode-selected long-cavity feedback is studied experimentally. Different dynamics are observed when different lateral modes are selected. When the feedback mirror is aligned perfectly and high-order modes are selected, in most....... When the feedback mirror is aligned non-perfectly, pulse-package oscillation is observed, for the first time to our knowledge, in a diode laser with long-cavity feedback....... of the cases, the output of the laser shows a periodic oscillation corresponding to a single roundtrip external-cavity loop, but the dynamic behavior disappears in some case; when the zero-order lateral-mode is selected, periodic oscillation corresponding to a double roundtrip external-cavity loop is observed...

Metal cutting by radiation from a CO2 laser with a self-filtering cavity

International Nuclear Information System (INIS)

Malikov, A G; Orishich, Anatolii M; Shulyat'ev, Viktor B

2009-01-01

The possibility of quality cutting by radiation from a CO 2 laser with an unstable self-filtering cavity (SFC) is experimentally investigated. The SFC provides the product of the divergence angle by the beam radius close to that for lower modes in a stable cavity (SC), however, at a higher radiation power, which favours faster cutting. In the far-field zone, the SFC beam has a diffraction structure with side maxima, which is usually considered as a negative factor in laser cutting. 25-mm-thick steel slabs have been cut. The comparison of the obtained results with known data on SC lasers shows that the principal characteristics of the cut (the width, edge roughness, specific expenditure of energy) are close in these lasers. A conclusion is made that at the chosen cavity parameters, the specific spatial structure of the SFC laser beam has no significant effect on the cut characteristics. (laser technologies)

Bistability of Cavity Magnon Polaritons

Science.gov (United States)

Wang, Yi-Pu; Zhang, Guo-Qiang; Zhang, Dengke; Li, Tie-Fu; Hu, C.-M.; You, J. Q.

2018-01-01

We report the first observation of the magnon-polariton bistability in a cavity magnonics system consisting of cavity photons strongly interacting with the magnons in a small yttrium iron garnet (YIG) sphere. The bistable behaviors emerged as sharp frequency switchings of the cavity magnon polaritons (CMPs) and related to the transition between states with large and small numbers of polaritons. In our experiment, we align, respectively, the [100] and [110] crystallographic axes of the YIG sphere parallel to the static magnetic field and find very different bistable behaviors (e.g., clockwise and counter-clockwise hysteresis loops) in these two cases. The experimental results are well fitted and explained as being due to the Kerr nonlinearity with either a positive or negative coefficient. Moreover, when the magnetic field is tuned away from the anticrossing point of CMPs, we observe simultaneous bistability of both magnons and cavity photons by applying a drive field on the lower branch.

Mechanical design and fabrication of power feed cavity test setup

International Nuclear Information System (INIS)

Ghodke, S.R.; Dhavle, A.S.; Sharma, Vijay; Sarkar, Shreya; Kumar, Mahendra; Nayak, Susanta; Barnwal, Rajesh; Jayaprakash, D.; Mondal, J.; Nimje, V.T.; Mittal, K.C.; Gantayet, L.M.

2013-01-01

Power feed cavity set up consists of nine number of accelerating cavity and eight numbers of coupling cavity for testing of power feed cavity with coupling flange for 2856 MHz S band standing wave coupled cavity linac. When we are assembling the cavity and applying the pressure, its resonance frequency changes with applied pressure/load. After some critical pressure/load frequency change becomes negligible or zero. This set up will be used to find out assembly performance of power feed cavity and its coupler. Top four cavity or eight half cells as well as bottom four cavity or eight half cells will be brazed separately. Power feed cavity will be sandwiched between this two brazed cavity assemblies. This paper discuss about linear motion bush, linear motion rod, load cell, hydraulic actuator, power pack, stepper motor PLC control, jig boring, alignment, tolerances and assembly procedure for this test setup. (author)

Progress on SCRF cavity manufacturing activities at RRCAT

International Nuclear Information System (INIS)

Puntambekar, A.; Dwivedi, J.; Mundra, G.; Srivastava, P.; Joshi, S.C.; Gupta, P.D.

2015-01-01

The work on development of SCRF cavities and associated technologies is ongoing at RRCAT to support its upcoming projects involving SC LINAC. RRCAT is also a member of Indian Institution Fermilab Collaboration (IIFC) working on development of SCRF cavities and associated technologies. Subsequent to 1.3 GHz single cell SCRF cavities, a 650 MHz single cell, a 1.3 GHz five cell and a 1.3 GHz nine cell SCRF cavities have been fabricated. These were tested for their mechanical, vacuum and RF qualifications at RRCAT for pre qualifications. The 1.3 GHz five cell SCRF cavity and 650 MHz single cell SCRF cavity has been processed and successfully tested at Fermi lab under IIFC. The 1.3 GHz five-cell cavity has achieved E acc of 20.3 MV/m at 2 K and 42 MV/m at 1.5-1.7 K with Q o of 2 x 10 10 . The 650 MHz single cell cavity has achieved the E acc > 19.3 MV/m with Q> 4x 10 10 at 2K. A 15 kW Electron Beam Welding (EBW) Machine has also been installed and commissioned at RRCAT as part of special infrastructure for development of SCRF cavities. One each 1.3 GHz and 650 MHz single cell SCRF cavities have also been fabricated using this EBW facility. Present focus of work is towards development of 650 MHz (β=0.92) multi-cell SCRF cavities. This paper will present the various technology development efforts on SCRF cavity fabrication, cavity test results and future plans. (author)

Modified 3½-Cell SC Cavity Made of Large Grain Niobium for the FZD SRF Photoinjector

CERN Document Server

Murcek, P; Michel, P; Moeller, K; Arnold, A; Teichert, J; Xiang, R; Freitag, M; Kneisel, P

2010-01-01

An SRF photoinjector has been successfully tested in FZD under the collaboration of BESSY, DESY, FZD, and MBI. In order to improve the gun cavity quality and thus reach a higher gradient, a new 3+1/2 superconducting cavity is being fabricated in cooperation with JLab. The modified cavity is made of large grain niobium, composed of one filter choke, one special designed half-cell (gun-cell) and three TESLA cavities. In this paper, the main updates of the new cavity design will be explained in detail. The deformation of the filter choke and the gun-cell, which is caused by pressure fluctuation in the He-line and also by the effect of the Lorentz force, will be minimized by stiffening between the filter choke and the gun-cell. Meanwhile, the cathode hole in the choke and gun-cell is enlarged for better rinsing. To simplify assembly, the NbTi pick-up will be welded directly on the wall of filter choke.

A 100-m Fabry–Pérot Cavity with Automatic Alignment Controls for Long-Term Observations of Earth’s Strain

Directory of Open Access Journals (Sweden)

Akiteru Takamori

2014-08-01

Full Text Available We have developed and built a highly accurate laser strainmeter for geophysical observations. It features the precise length measurement of a 100-m optical cavity with reference to a stable quantum standard. Unlike conventional laser strainmeters based on simple Michelson interferometers that require uninterrupted fringe counting to track the evolution of ground deformations, this instrument is able to determine the absolute length of a cavity at any given time. The instrument offers advantage in covering a variety of geophysical events, ranging from instantaneous earthquakes to crustal deformations associated with tectonic strain changes that persist over time. An automatic alignment control and an autonomous relocking system have been developed to realize stable performance and maximize observation times. It was installed in a deep underground site at the Kamioka mine in Japan, and an effective resolution of 2 × (10−8 − 10−7 m was achieved. The regular tidal deformations and co-seismic strain changes were in good agreement with those from a theoretical model and a co-located conventional laser strainmeter. Only the new instrument was able to record large strain steps caused by a nearby large earthquake because of its capability of absolute length determination.

The HIE-ISOLDE alignment and monitoring system software and test mock up

CERN Document Server

Kautzmann, G; Kadi, Y; Leclercq, Y; Waniorek, S; Williams, L

2012-01-01

For the HIE Isolde project a superconducting linac will be built at CERN in the Isolde facility area. The linac will be based on the creation and installation of 2 high- β and 4 low- β cryomodules containing respectively 5 high-β superconducting cavities and 1 superconducting solenoid for the two first ones, 6 low-β superconducting cavities and 2 superconducting solenoids for the four other ones. An alignment and monitoring system of the RF cavities and solenoids placed inside the cryomodules is needed to reach the optimum linac working conditions. The alignment system is based on opto-electronics, optics and precise mechanical instrumentation. The geometrical frame configuration, the data acquisition and the 3D adjustment will be managed using a dedicated software application. In parallel to the software development, an alignment system test mock-up has been built for software validation and dimensional tests. This paper will present the software concept and the development status, and then will describe...

The optimized advanced demonstrator for the SC CW heavy ion linac at GSI

Energy Technology Data Exchange (ETDEWEB)

Schwarz, Malte; Basten, Markus; Busch, Marco; Dziuba, Florian; Podlech, Holger; Ratzinger, Ulrich; Tiede, Rudolf [Institut fuer Angewandte Physik, Goethe-Universitaet Frankfurt am Main (Germany); Gettmann, Viktor; Heilmann, Manuel [GSI Helmholtzzentrum, Darmstadt (Germany); Barth, Winfried; Mickat, Sascha [GSI Helmholtzzentrum, Darmstadt (Germany); HIM, Helmholtzinstitut, Mainz (Germany); Miski-Oglu, Maksym [HIM, Helmholtzinstitut, Mainz (Germany); Aulenbacher, Kurt [KPH, Johannes Gutenberg Universitaet, Mainz (Germany)

2016-07-01

For future experiments with heavy ions at the coulomb barrier within the SHE research project a multi-stage R and D program of GSI, HIM and IAP is currently under progress. It aims at developing a superconducting (sc) continuous wave (cw) LINAC with multiple CH-cavities as key components. As intermediate step towards the whole LINAC, the Optimized Advanced Demonstrator is proposed. Consisting of short CH-cavities and cryostats, it could provide several advantages regarding velocity acceptance, higher tolerance with respect to frequency and field deviation, easier mounting, handling and maintenance as well as a more robust longitudinal beam dynamic. The beam dynamics concept is based on EQUUS (Equidistant Multigap Structure) constant-beta cavities. The corresponding simulations for the proposed next extension stage - the Optimized Advanced Demonstrator - will be presented.

DC-SC Photoinjector with Low Emittance at Peking University

CERN Document Server

Xiang Rong; Hao, J; Huang, Senlin; Lu Xiang Yang; Quan, Shengwen; Zhang, Baocheng; Zhao, Kui

2005-01-01

High average power Free Electron Lasers require the high quality electron beams with the low emittance and the sub-picosecond bunches. The design of DC-SC photoinjector, directly combining a DC photoinjector with an SRF cavity, can produce high average current beam with moderate bunch charge and high duty factor. Because of the DC gun, the emittance increases quickly at the beginning, so a carefully design is needed to control that. In this paper, the simulation of an upgraded design has been done to lower the normalized emittance below 1.5mm·mrad. The photoinjector consists of a DC gap and a 2+1/2-cell SRF cavity, and it is designed to produce 4.2 MeV electron beams at 100pC bunch charge and 81.25MHz repetition rate (8 mA average current).

An Alignment of J-PARC Linac

CERN Document Server

Morishita, Takatoshi; Hasegawa, Kazuo; Ikegami, Masanori; Ito, Takashi; Kubota, Chikashi; Naito, Fujio; Takasaki, Eiichi; Tanaka, Hirokazu; Ueno, Akira; Yoshino, Kazuo

2005-01-01

J-PARC linear accelerator components are now being installed in the accelerator tunnel, whose total length is more than 400 m including the beam transport line to RCS (Rapid Cycling Synchrotron). A precise alignment of accelerator components is essential for a high quality beam acceleration. In this paper, planned alignment schemes for the installation of linac components, the fine alignment before beam acceleration, and watching the long term motion of the building are described. Guide points are placed on the floor, which acts as a reference for the initial alignment at the installation and also as a relay point for the long surveying network linking at the fine alignment. For a straight line alignment, the wire position sensor is placed on the offset position with respect to the beam center by a target holder, then a single wire can cover the accelerator cavities and the focusing magnets at the DTL-SDTL section (120m). The hydrostatic levering system (HLS) is used for watching the floor elevation (changes)...

SC*994C>T causes the Sc(null) phenotype in Pacific Islanders and successful transfusion of Sc3+ blood to a patient with anti-Sc3.

Science.gov (United States)

Reid, Marion E; Hue-Roye, Kim; Velliquette, Randall W; Larimore, Kathleen; Moscarelli, Sue; Ohswaldt, Nicolas; Lomas-Francis, Christine

2013-01-01

Antigens in the SC blood group system are expressed by the human erythrocyte membrane-associated protein (ERMAP).Two molecular bases have been reported for the Sc,un phenotype:SC*307del2 and SC*994C>T. We report our investigation of the molecular background of five Sc,n1 individuals from the Pacific Islands and describe the successful transfusion of Sc3+ blood to a patient with anti-Sc3 in her plasma. SC (ERMAP) exons 2,3, and 12 and their flanking intronic regions were analyzed. TheSC*994C>T change introduces a restriction enzyme cleavage site for Tsp45I, and polymerase chain reaction (PCR) products from exon 12 were subjected to this PCR-restriction fragment length polymorphism (RFLP) assay. The five samples had the variant SC*994T/T. One sample, from a first cousin of one Marshallese proband, was heterozygous for SC*1514C/T (in the 3' untranslated region); the other four samples were SC*1514C/C(consensus sequence). Samples from white donors (n = 100) and African American donors (n = 99) were tested using the Tsp45IPCR-RFLP assay; all gave a banding pattern that was consistent with the SC*994C/C consensus sequence. In all five samples,our analyses showed homozygosity for the nonsense nucleotide change SC*994C>Tin an allele carrying the nucleotide associated with SLd. Further investigation determined that one of the probands reported previously with the SC*994C>T change was from the Marshall Islands (which form part of the Micronesian Pacific Islands) and the other was from an unspecified location within the large collection of Pacific Islands. Taken together, the five known probands with the SC*994C>T silencing nucleotide change were from the Pacific Islands.

Sc-W-Si and Sc-W-Ge ternary systems

International Nuclear Information System (INIS)

Kotur, B.Ya.; Voznyak, O.M.; Bodak, O.I.

1989-01-01

Phase equilibria in Sc-W-Si and Sc-W-Ge ternary systems are investigated at 1070 K. Sc 2+x W 3-x Si 4 ternary compound (0≤x≤1) is determined, its crystal structure (Ce 2 Sc 3 Si 4 structural type), as well as, change of elementary cell parameters and microhardness within homogeneity range are determined. Regularities of component interaction within Sc-M-Si(Ge) (M-Cr, Mo, W) ternary system are determined. Ternary systems with Mo and W are more closer to each other according to the phase equilibria character, than to ternary systems with Cr

Slot-coupled CW standing wave accelerating cavity

Energy Technology Data Exchange (ETDEWEB)

Wang, Shaoheng; Rimmer, Robert; Wang, Haipeng

2017-05-16

A slot-coupled CW standing wave multi-cell accelerating cavity. To achieve high efficiency graded beta acceleration, each cell in the multi-cell cavity may include different cell lengths. Alternatively, to achieve high efficiency with acceleration for particles with beta equal to 1, each cell in the multi-cell cavity may include the same cell design. Coupling between the cells is achieved with a plurality of axially aligned kidney-shaped slots on the wall between cells. The slot-coupling method makes the design very compact. The shape of the cell, including the slots and the cone, are optimized to maximize the power efficiency and minimize the peak power density on the surface. The slots are non-resonant, thereby enabling shorter slots and less power loss.

Design and Prototype Progress toward a Superconducting Crab Cavity Cryomodule for the APS

International Nuclear Information System (INIS)

Wang, Haipeng; Cheng, Guangfeng; Ciovati, Gianluigi; Henry, James; Kneisel, Peter; Rimmer, Robert; Slack, Gary; Turlington, Larry; waldschmidt, Geoff; Nassiri, Alireza

2010-01-01

A squashed, elliptical supercondconducting (SC) cavity with waveguide dampers on the beam pipes has currently been chosen as the baseline design for the Short Pulse X-ray (SPX) project at the Advanced Photon Source (APS). An alternate cavity design, with a waveguide damper located directly on the cavity cell for improved damping characteristics, has also been designed and cold-tested with promising results. In either case, eight cavities would be operated CW in a single cryomodule at 2K to produce an electron bunch chirp of 4MV at a frequency of 2.815 GHz. Detailed analysis of multipactoring (MP), Lorentz force detuning (LFD), and the thermal properties of the baseline design has led to an engineering specification of the basic parameters of the cryomodule.

Foreshock-like density cavity in the outflow region of magnetotail reconnection

Directory of Open Access Journals (Sweden)

C. L. Cai

2009-08-01

Full Text Available During Cluster spacecraft crossing of the magnetotail, a novel density depleted cavity in association with magnetic compressions in the outflow region of reconnection was observed. It contains intense reflected field-aligned particles, which are produced by a generation mechanism similar to that of the terrestrial foreshock, and hence manifests a foreshock-like morphology. In this cavity, reflected field-aligned proton beams were observed and simultaneously the feature of magnetic-mirror loss-cone proton distributions were found. Magnetic field fluctuations, especially quasi-monochromatic oscillations, were recorded. Both the leading egde and the ULF wave boundary of the ion foreshock are identified from the time sequence of proton and magnetic field observations. Just upstream of the leading egde of the ion foreshock, reflected field-aligned electrons were detected, whose distribution has a narrow bump-on-tail pattern. However, close to the shock front, reflected electrons with a broad bump-on-tail pattern was measured. These two different manifestations of reflected electrons reveal the differences in their microscopic physics of the reflecting process. Moreover, a part of incident ions was further accelerated in the cavity due to trans-time magnetic pumping which provides another possible mechanism in the multi-step acceleration processes in reconnection.

A novel micromachined shadow mask system with self-alignment and gap control capability

International Nuclear Information System (INIS)

Hong, Jung Moo; Zou Jun

2008-01-01

We present a novel micromachined shadow mask system, which is capable of accurate self-alignment and mask-substrate gap control. The shadow mask system consists of a silicon shadow mask and a silicon carrier wafer with pyramidal cavities fabricated with bulk micromachining. Self-alignment and gap control of the shadow mask and the fabrication substrate can readily be achieved by using matching pairs of pyramidal cavities and steel spheres placed between. The layer-to-layer alignment accuracy of the new shadow mask system has been experimentally characterized and verified using both optical and atomic force microscopic measurements. As an application of this new shadow mask system, an organic thin-film transistor (OTFT) using pentacene as the semiconductor layer has been successfully fabricated and tested

Beam position diagnostics with higher order modes in third harmonic superconducting accelerating cavities

International Nuclear Information System (INIS)

Zhang, Pei

2013-02-01

Higher order modes (HOM) are electromagnetic resonant fields. They can be excited by an electron beam entering an accelerating cavity, and constitute a component of the wakefield. This wakefield has the potential to dilute the beam quality and, in the worst case, result in a beam-break-up instability. It is therefore important to ensure that these fields are well suppressed by extracting energy through special couplers. In addition, the effect of the transverse wakefield can be reduced by aligning the beam on the cavity axis. This is due to their strength depending on the transverse offset of the excitation beam. For suitably small offsets the dominant components of the transverse wakefield are dipole modes, with a linear dependence on the transverse offset of the excitation bunch. This fact enables the transverse beam position inside the cavity to be determined by measuring the dipole modes extracted from the couplers, similar to a cavity beam position monitor (BPM), but requires no additional vacuum instrumentation. At the FLASH facility in DESY, 1.3 GHz (known as TESLA) and 3.9 GHz (third harmonic) cavities are installed. Wakefields in 3.9 GHz cavities are significantly larger than in the 1.3 GHz cavities. It is therefore important to mitigate the adverse effects of HOMs to the beam by aligning the beam on the electric axis of the cavities. This alignment requires an accurate beam position diagnostics inside the 3.9 GHz cavities. It is this aspect that is focused on in this thesis. Although the principle of beam diagnostics with HOM has been demonstrated on 1.3 GHz cavities, the realization in 3.9 GHz cavities is considerably more challenging. This is due to the dense HOM spectrum and the relatively strong coupling of most HOMs amongst the four cavities in the third harmonic cryo-module. A comprehensive series of simulations and HOM spectra measurements have been performed in order to study the modal band structure of the 3.9 GHz cavities. The dependencies of

Beam position diagnostics with higher order modes in third harmonic superconducting accelerating cavities

Energy Technology Data Exchange (ETDEWEB)

Zhang, Pei

2013-02-15

Higher order modes (HOM) are electromagnetic resonant fields. They can be excited by an electron beam entering an accelerating cavity, and constitute a component of the wakefield. This wakefield has the potential to dilute the beam quality and, in the worst case, result in a beam-break-up instability. It is therefore important to ensure that these fields are well suppressed by extracting energy through special couplers. In addition, the effect of the transverse wakefield can be reduced by aligning the beam on the cavity axis. This is due to their strength depending on the transverse offset of the excitation beam. For suitably small offsets the dominant components of the transverse wakefield are dipole modes, with a linear dependence on the transverse offset of the excitation bunch. This fact enables the transverse beam position inside the cavity to be determined by measuring the dipole modes extracted from the couplers, similar to a cavity beam position monitor (BPM), but requires no additional vacuum instrumentation. At the FLASH facility in DESY, 1.3 GHz (known as TESLA) and 3.9 GHz (third harmonic) cavities are installed. Wakefields in 3.9 GHz cavities are significantly larger than in the 1.3 GHz cavities. It is therefore important to mitigate the adverse effects of HOMs to the beam by aligning the beam on the electric axis of the cavities. This alignment requires an accurate beam position diagnostics inside the 3.9 GHz cavities. It is this aspect that is focused on in this thesis. Although the principle of beam diagnostics with HOM has been demonstrated on 1.3 GHz cavities, the realization in 3.9 GHz cavities is considerably more challenging. This is due to the dense HOM spectrum and the relatively strong coupling of most HOMs amongst the four cavities in the third harmonic cryo-module. A comprehensive series of simulations and HOM spectra measurements have been performed in order to study the modal band structure of the 3.9 GHz cavities. The dependencies of

Fermilab linac upgrade side coupled cavity temperature control system

International Nuclear Information System (INIS)

Crisp, J.; Satti, J.

1991-05-01

Each cavity section has a temperature control system which maintains the resonant frequency by exploiting the 17.8 ppm/degree C frequency sensitivity of the copper cavities. Each accelerating cell has a cooling tube brazed azimuthally to the outside surface. Alternate supply and return connection to the water manifolds reduce temperature gradients and maintain physical alignment of the cavity string. Special tubing with spiral inner fins and large flow rate are used to reduce the film coefficient. Temperature is controlled by mixing chilled water with the water circulating between the cavity and the cooling skid located outside the radiation enclosure. Chilled water flow is regulated with a valve controlled by a local microcomputer. The temperature loop set point will be obtained from a slower loop which corrects the phase error between the cavity section and the rf drive during normal beam loaded conditions. Time constants associated with thermal gradients induced in the cavity with the rf power require programming it to the nominal 7.1 MW level over a 1 minute interval to limit the reverse power. 4 refs., 4 figs

Structure and bonding of ScCN and ScNC: Ground and low-lying states

International Nuclear Information System (INIS)

Kalemos, Apostolos; Metropoulos, Aristophanes; Mavridis, Aristides

2012-01-01

Graphical abstract: The experimentally unknown systems ScCN and ScNC have been studied through single reference CISD and CCSD(T) methods. A total of 20 = 10 (ScCN) + 10 (ScNC) states were examined. All states are quite ionic whereas ScNC(X ∼3 Δ) is stabler than ScCN(X ∼3 Δ) by ∼5 kcal/mol. Display Omitted Highlights: ► We have studied through ab initio methods the polytopic system Sc[CN]. ► A series of low lying states for both isomeric forms have been examined. ► Around equilibrium the system displays a pronounced Sc + [CN] − ionic character. - Abstract: We have studied the experimentally unknown Sc[CN] molecular system in both its isomeric forms, scandium cyanide (ScCN) and isocyanide (ScNC), through ab initio computations. We report energetics, geometries, harmonic frequencies, and dipole moments for the first 20 Sc[CN] states correlating diabatically to Sc + ( 3 D, 1 D, 3 F) + CN − (X 1 Σ + ). Both isomers have a pronounced ionic character around equilibrium due to the high electron affinity of the CN group and the low ionization energy of the Sc atom. According to our calculations the ScNC isomer (X ∼3 Δ) is stabler than the ScCN(X ∼3 Δ) by ∼5 kcal/mol.

Intra-pulse Cavity Enhanced Measurements of Carbon Monoxide in a Rapid Compression Machine

KAUST Repository

Nasir, Ehson Fawad

2018-05-07

A laser absorption sensor for carbon monoxide concentration was developed for combustion studies in a rapid compression machine using a pulsed quantum cascade laser near 4.89 μm. Cavity enhancement reduced minimum detection limit down to 2.4 ppm at combustion relevant conditions. Off-axis alignment and rapid intra-pulse down-chirp resulted in effective suppression of cavity noise.

Coupler Development and Gap Field Analysis for the 352 MHz Superconducting CH-Cavity

CERN Document Server

Liebermann, H; Ratzinger, U; Sauer, A C

2004-01-01

The cross-bar H-type (CH) cavity is a multi-gap drift tube structure based on the H-210 mode currently under development at IAP Frankfurt and in collaboration with GSI. Numerical simulations and rf model measurements showed that the CH-type cavity is an excellent candidate to realize s.c. multi-cell structures ranging from the RFQ exit energy up to the injection energy into elliptical multi-cell cavities. The reasonable frequency range is from about 150 MHz up to 800 MHz. A 19-cell, β=0.1, 352 MHz, bulk niobium prototype cavity is under development at the ACCEL-Company, Bergisch-Gladbach. This paper will present detailed MicroWave Studio simulations and measurements for the coupler development of the 352 MHz superconducting CH cavity. It will describe possibilities for coupling into the superconducting CH-Cavity. The development of the coupler is supported by measurement on a room temperature CH-copper model. We will present the first results of the measurements of different couplers, e.g. capacitiv...

Niobium Coatings for the HIE-ISOLDE QWR Superconducting Accelerating Cavities

CERN Document Server

Jecklin, N; Delaup, B; Ferreira, L; Mondino, I; Sublet, A; Therasse, M; Venturini Desolaro, W

2013-01-01

The HIE-ISOLDE (High Intensity and Energy at ISOLDE) project is the upgrade of the existing ISOLDE (Isotope Separator On Line DEvice) facility at CERN, which is dedicated to the production of a large variety of radioactive ion beams for nuclear physics experiments. A new linear accelerator made of 20 ȕ=10.3% and 12 ȕ=6.3% quarter-wave resonators (QWR) superconducting (SC) accelerating cavities at 101 MHz will be built, and in a first phase two cryomodules of 5 high-ȕ cavities each are scheduled to accelerate first beams in 2015. The cavities are made of a copper substrate, with a sputter-coated superconductive niobium (Nb) layer, operated at 4.5 K with an accelerating field of 6 MV/m at 10W Radio-Frequency (RF) losses (Q=4.5· 108). In this paper we will discuss the baseline surface treatment and coating procedure which allows obtaining the required performance, as well as the steps undertaken in order to prepare series production of the required number of cavities guaranteeing their quality and functional...

Sc-45 nuclear magnetic resonance analysis of precipitation in dilute Al-Sc alloys

NARCIS (Netherlands)

Celotto, S; Bastow, TJ

Nuclear magnetic resonance (NMR) with Sc-45 is used to determine the solid solubility of scandium in aluminium and to follow the precipitation of Al3Sc during the ageing of an Al-0.06 at.% Sc alloy via the two fully resolved peaks, corresponding to Sc in the solid solution Al matrix and to Sc in the

Crystal structure and phase stability of AlSc in the near-equiatomic Al–Sc alloy

Energy Technology Data Exchange (ETDEWEB)

Li, Juan; Huang, Li; Liang, Yongfeng [State Key Laboratory for Advanced Metals and Materials, University of Science and Technology Beijing, 30 Xueyuan Road, Beijing 100083 (China); Ye, Feng, E-mail: yefeng@skl.ustb.edu.cn [State Key Laboratory for Advanced Metals and Materials, University of Science and Technology Beijing, 30 Xueyuan Road, Beijing 100083 (China); Lin, Junpin [State Key Laboratory for Advanced Metals and Materials, University of Science and Technology Beijing, 30 Xueyuan Road, Beijing 100083 (China); Shang, Shunli; Liu, Zikui [Department of Materials Science and Engineering, The Pennsylvania State University, University Park, PA 16802 (United States)

2015-01-05

Highlights: • Two lattice structures of equiatomic Al–Sc compounds are confirmed. • Al–Sc phase at Sc 50 at.% has a space group of Pbam. • Al–Sc phase at Sc 55 at.% has a space group of B2. • B2 AlSc is a metastable phase with Sc 50 at.%. • Lattice transition between two compounds is proposed under local thermal stress. - Abstract: Intermetallic compound AlSc is found in the equiatomic Al–Sc binary alloy. The present work indicates that the orthorhombic AlSc with the Au{sub 2}CuZn-type structure can be formed at 50 at.% Sc, while the CsCl-type (B2) AlSc will be formed at 55 at.% Sc. After annealing at 1100 °C, some orthorhombic AlSc grains transit to the B2 structure, and the annealing at lower temperatures leads to the disappearance of B2 phase, indicating that the B2 AlSc is also a metastable phase in the alloy at lower Sc content (<50 at.%). First-principle calculations at 0 K reveal that the orthorhombic AlSc is more stable than the B2 AlSc with the energy difference between them being 5.4 meV/atom. The fast transition between these two phases, which cannot be interpreted by the mechanism of atomic diffusion, was tentatively analyzed by the volume change based on the calculated atomic positions of these two phases.

46 CFR 7.70 - Folly Island, SC to Hilton Head Island, SC.

Science.gov (United States)

2010-10-01

... 46 Shipping 1 2010-10-01 2010-10-01 false Folly Island, SC to Hilton Head Island, SC. 7.70 Section... BOUNDARY LINES Atlantic Coast § 7.70 Folly Island, SC to Hilton Head Island, SC. (a) A line drawn from the...′ W. (Port Royal Sound Lighted Whistle Buoy “2PR”); thence to the easternmost extremity of Hilton Head...

Effect of lectin (ScLL on fibroblasts stimulated with LPS - an in vitro study

Directory of Open Access Journals (Sweden)

Manuella Verdinelli de Paula REIS

Full Text Available Abstract: The lectin (ScLL extracted from the Synadenium carinatum plant has been evaluated as an immunomodulator in diseases such as asthma, neosporosis and leishmaniasis. However, it has not yet been evaluated in the oral cavity. This study evaluated the effect of ScLL on viability, proliferation and release of IL-10 in human gingival fibroblasts (HGF stimulated with lipopolysaccharide (LPS. HGF were stimulated with LPS 1 µg/ml and treated with ScLL in concentrations of 10, 5 and 2 µg/ml for 1 and 5 h, and evaluated by flow cytometry for viability, apoptosis (initial/advanced and necrosis. The supernatant was collected to detect release of IL-10 by ELISA. The proliferation was assessed with the BrdU assay. Positive control consisted of cells maintained in Dulbecco's Modified Eagles Medium (DMEM, and the negative control, of those kept in tap water. Data were analyzed by ANOVA and Dunnett's test (α = 0.05. No significant difference was found for ScLL concentrations regarding viability or initial and advanced apoptosis (p=0.455. All the groups, including the positive control, had a significantly lower necrosis parameter than negative control at 5 h (p < 0.001. No difference was found for proliferation among the experimental groups (p = 0.832. ScLL at 5 and 2 µg/ml resulted in a lower release of IL-10 than positive and negative controls at 5 h (p = 0.047. The results indicated that ScLL concentrations tested were not cytotoxic, and had no effect on proliferation and release of IL-10 parameters. A thorough understanding of ScLL, regarding its immunomodulatory potential, may open the door to new perspectives for dentistry.

High-resolution clean-sc

NARCIS (Netherlands)

Sijtsma, P.; Snellen, M.

2016-01-01

In this paper a high-resolution extension of CLEAN-SC is proposed: HR-CLEAN-SC. Where CLEAN-SC uses peak sources in “dirty maps” to define so-called source components, HR-CLEAN-SC takes advantage of the fact that source components can likewise be derived from points at some distance from the peak,

Investigation of Accelerated Partial Breast Patient Alignment and Treatment With Helical Tomotherapy Unit

International Nuclear Information System (INIS)

Langen, Katja M.; Buchholz, Daniel J.; Burch, Doug R. C.; Burkavage, Rob C.; Limaye, Arti U.; Meeks, Sanford L.; Kupelian, Patrick A.; Ruchala, Kenneth J.; Haimerl, Jason; Henderson, Doug; Olivera, Gustavo H.

2008-01-01

Purpose: To determine the precision of megavoltage computed tomography (MVCT)-based alignment of the seroma cavity for patients undergoing partial breast irradiation; and to determine whether accelerated partial breast irradiation (APBI) plans can be generated for TomoTherapy deliveries that meet the National Surgical Adjuvant Breast and Bowel Project (NSABP) B-39/Radiation Therapy Oncology Group (RTOG) 0413 protocol guidelines for target coverage and normal tissue dose limitations. Methods and Materials: We obtained 50 MVCT images from 10 patients. An interuser study was designed to assess the alignment precision. Using a standard helical and a fixed beam prototype ('topotherapy') optimizer, two APBI plans for each patient were developed. Results: The precision of the MVCT-based seroma cavity alignment was better than 2 mm if averaged over the patient population. Both treatment techniques could be used to generate acceptable APBI plans for patients that fulfilled the recommended NSABP B-39/RTOG-0413 selection criteria. For plans of comparable treatment time, the conformation of the prescription dose to the target was greater for helical deliveries, while the ipsilateral lung dose was significantly reduced for the topotherapy plans. Conclusions: The inherent volumetric imaging capabilities of a TomoTherapy Hi-Art unit allow for alignment of patients undergoing partial breast irradiation that is determined from the visibility of the seroma cavity on the MVCT image. The precision of the MVCT-based alignment was better than 2 mm (± standard deviation) when averaged over the patient population. Using the NSABP B-39/RTOG-0413 guidelines, acceptable APBI treatment plans can be generated using helical- or topotherapy-based delivery techniques

Quasilinear infiltration from an elliptical cavity

Science.gov (United States)

Kuhlman, Kristopher L.; Warrick, Arthur W.

2008-08-01

We develop analytic solutions to the linearized steady-state Richards equation for head and total flowrate due to an elliptic cylinder cavity with a specified pressure head boundary condition. They are generalizations of the circular cylinder cavity solutions of Philip [Philip JR. Steady infiltration from circular cylindrical cavities. Soil Sci Soc Am J 1984;48:270-8]. The circular and strip sources are limiting cases of the elliptical cylinder solution, derived for both horizontally- and vertically-aligned ellipses. We give approximate rational polynomial expressions for total flowrate from an elliptical cylinder over a range of sizes and shapes. The exact elliptical solution is in terms of Mathieu functions, which themselves are generalizations of and computed from trigonometric and Bessel functions. The required Mathieu functions are computed from a matrix eigenvector problem, a modern approach that is straightforward to implement using available linear algebra libraries. Although less efficient and potentially less accurate than the iterative continued fraction approach, the matrix approach is simpler to understand and implement and is valid over a wider parameter range.

HIE ISOLDE Alignment and monitoring system technical design and project status

CERN Document Server

Gayde, J C; Kautzmann, G; Leclercq, Y; Waniorek, S; Williams, L

2012-01-01

In the frame of the HIE ISOLDE project most of the existing ISOLDE REX line will be replaced by a superconducting linac in order to upgrade the energy and intensity of the REX ISOLDE facility at CERN. Beam-physics simulations show that the optimum linac working conditions are obtained when the main axes of the active components, RF cavities and solenoid placed inside the cryostats, are aligned and permanently monitored on the REX Nominal Beam Line (NBL) within a precision of 0.3 mm for the cavities and 0.15 mm for the solenoids at one sigma level along directions perpendicular to the beam axis. This paper presents the proposed adjustment and alignment system based on opto-electronic sensors, optics and precise mechanic elements which are used, for some of them, in various non-standard environmental conditions such as high vacuum, cryogenic temperatures.

Determination of Sc and Th in ScI3-NaI-ThI4 sample

International Nuclear Information System (INIS)

Yuan Hui; Yang Zhihong

1999-01-01

Determination of Sc and Th in ScI 3 -NaI-ThI 4 sample is studied by X-ray fluorescence and complexometry. The effect of working condition of Sc on X-ray fluorescence spectrometer and different sample-making method on the determination of Sc and Th are studied experimentally. The X-ray fluorescence analysis of determination of Sc and Th is developed by polyester film sample-making technique, the measuring precision of Sc and Th is better than 4%. The effect of acidity and temperature on the determining end point of titration is obvious. The results of different complexometric methods are compared. The precision of Sc and Th is less than 2% by comlexometry, it is fit for the routine analysis of ScI 3 -NaI-ThI 4 sample

Method of increasing power within an optical cavity with long path lengths

Energy Technology Data Exchange (ETDEWEB)

Leen, John Brian; Bramall, Nathan E.

2018-03-13

A cavity-enhanced absorption spectroscopy instrument has an optical cavity with two or more cavity mirrors, one mirror of which having a hole or other aperture for injecting a light beam, and the same or another mirror of which being partially transmissive to allow exit of light to a detector. A spherical-spherical configuration with at least one astigmatic mirror or a spherical-cylindrical configuration where the spherical mirror could also be astigmatic prevents a reentrant condition wherein the injected beam would prematurely exit the cavity through the aperture. This combination substantially increases the number of passes of the injected beam through a sample volume for sensitive detection of chemical species even in less than ideal conditions including low power laser or LED sources, poor mirror reflectivity or detector noise at the wavelengths of interest, or cavity alignment issues such as vibration or temperature and pressure changes.

Preparation and handling of surfaces for superconducting radio frequency cavities

International Nuclear Information System (INIS)

Bloess, D.

1988-01-01

Fortunately, surface treatment for s.c. cavities knows only one simple rule. If one observes this rule strictly one will be successful, if not, one will fail! The rule is CLEANLINESS. This means: clean material (high purity niobium without inclusions), clean (analytical grade) polishing chemicals and solvents, ultraclean (semiconductor grade) rinsing water, ultraclean (class 100) assembly environment. In general, if one applies the same working practice as the semiconductor industry, one will produce surfaces that are less clean than silicon wafers, due to the shape of the cavity (an inner surface is much more difficult to clean than a flat wafer); due to its size and due to the material (niobium is hydrophilic which makes the water with all the dirt in it stick to the surface). 9 references

Suspended polytetrafluoroethylene nanostructure electret film in dual variable cavities for self-powered micro-shock sensing

Science.gov (United States)

Zhu, Jianxiong; Chen, Cong; Guo, Xiaoyu

2018-04-01

We report a suspended polytetrafluoroethylene (PTFE) nanostructure electret film in dual variable cavities for a self-powered micro-shock sensing application. The prototype contained series variable air cavities, a suspended nanostructure PTFE electret film and independent electrode films. The charges on the suspended nanostructure PTFE electret film provided the electrostatic field around the electret film in the series variable air cavities. When the reported device was driven by a micro-shock pressure, the inducted electrostatic charges on both the top and bottom electrodes would vary as the micro-shock pressing or releasing. Experimental results showed that the maximum of a short-circuit current density (J sc ) and an open-circuit voltage (V oc ) reached 3 ± 0.1 nA cm‑2 and 3.6 ± 0.1 V, respectively. It was found that the parameter J sc was more advantageous in identifying stronger shocks (parameter acceleration a bigger than 0.1 m s‑2), whereas the parameter V oc was more sensitive for weaker shocks, such as acceleration a smaller than 0.1 m s‑2. Moreover, finger continuous micro-shock pressure taps application was used to demonstrate the mechanical energy conversion performance with 4.5 ± 0.2 V open-circuit voltages. The research on the nanostructure electret PTFE film in series dual variable air cavities not only gave us a fresh idea about the principle and design of the shocking sensor, but also provided an easy fabrication and a low cost shocking sensor for the Internet of Things (IoT) systems.

Process of DC-SC photoinjector

International Nuclear Information System (INIS)

Xiang Rong; Zhao Kui; Quan Shengwen; Ding Yuantao; Zhang Baocheng; Lu Xiangyang; Lin Lin; Wang Lifang; Chen Jiaer

2004-01-01

The DC-SC photoinjector at Beijing University is designed to provide an electron beam of average current 1 mA with the energy of 2-3 MeV and normalized rms transverse emittance of 3πmm-mrad at an 81.25 MHz repetition rate. The test facility has been completely installed in our lab. In this paper some of the ongoing experimental activities are summarized. First results from the cold test of superconducting cavity have been presented. According to the results, authors have improved the main coupler to repress the multipacting. The beam test of 100 μA on the DC gun has been done, photocathode preparation chamber can produce Cs 2 Te cathodes, and the laser system can provide laser pulse with 266 nm wavelength. The time synchronization between laser and RF power has been achieved by a timing stabilizer. A new method using 'due image pattern' of Cherenkov radiation will be commissioned to measure beam emittance. The next step is under way, to prepare all the equipment for the beam tests. (authors)

33 CFR 80.712 - Morris Island, SC to Hilton Head Island, SC.

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Morris Island, SC to Hilton Head..., SC to Hilton Head Island, SC. (a) A line drawn from the easternmost tip of Folley Island to the... easternmost extremity of Hilton Head at latitude 32°13.0′ N. longitude 80°40.1′ W. [CGD 77-118a, 42 FR 35784...

Toxicity, tissue distribution and excretion of 46ScCl3 and 46Sc-EDTA in mice

International Nuclear Information System (INIS)

Lachine, E.E.; Noujaim, A.A.; Ediss, C.; Wiebe, L.I.

1976-01-01

The acute toxicity, differential distribution in tissue, and elimination of ScCl 3 , 46 ScCl 3 , Sc-EDTA and 46 Sc-EDTA, in mice, has been investigated. The LD 50 sup(24hr) doses for ScCl 3 were 440 and 24 mg kg -1 respectively after intraperitioneal and intravenous injection, and 720 and 108 mg kg -1 respectively for Sc-EDTA. 46 ScCl 3 was extensively deposited in the liver and the spleen. 46 Sc-EDTA was rapidly taken up by the kidney with subsequent elimation via the urine. While-body desaturation kinetics for 46 Sc-EDTA were found to fit a three compartmental model. The fast elimination phase (T1/2 = 12.75 min; K = 0.05540 min -1 ) accounted for 74.6% of the dose; the intermediate phase (T1/2 = 40.2 min; K = 0.01722 min -1 ) for 21.8%, and the slow (T1/2 = 5351 min; K = 0.00013 min -1 ) for 3.6% of the dose. (author)

Magnetic moment of {sup 48}Sc

Energy Technology Data Exchange (ETDEWEB)

Ohtsubo, T., E-mail: tohtsubo@np.gs.niigata-u.ac.jp; Kawamura, Y.; Ohya, S. [Niigata University, Department of Physics (Japan); Izumikawa, T. [Niigata University, Radioisotope Center (Japan); Nishimura, K. [Toyama University, Faculty of Engineering (Japan); Muto, S. [Neutron Science Laboratory, KEK (Japan); Shinozuka, T. [Tohoku University, Cyclotron and Radioisotope Center (Japan)

2007-11-15

Nuclear magnetic resonances were measured for {sup 48}Sc and {sup 44m}Sc oriented at 8 mK in an Fe host metal. The magnetic hyperfine splitting frequencies at an external magnetic field of 0.2 T were determined to be 63.22(11) MHz and 64.81(1) MHz for {sup 48}Sc and {sup 44m}Sc, respectively. With the known magnetic moment of {mu}({sup 44m}Sc)=+3.88 (1) {mu}{sub N}, the magnetic moment of {sup 48}Sc is deduced as {mu}({sup 44}Sc)=+3.785(12) {mu}{sub N}. The measured magnetic moment of {sup 48}Sc is discussed in terms of the shell model using the effective interactions.

Suppression of multipacting in high power RF couplers operating with superconducting cavities

Energy Technology Data Exchange (ETDEWEB)

Ostroumov, P.N., E-mail: ostroumov@frib.msu.edu [Facility for Rare Isotope Beams (FRIB), Michigan State University, East Lansing, MI 48824 (United States); Kazakov, S. [Fermi National Accelerator Laboratory, Batavia, IL 60510 (United States); Morris, D.; Larter, T.; Plastun, A.S.; Popielarski, J.; Wei, J.; Xu, T. [Facility for Rare Isotope Beams (FRIB), Michigan State University, East Lansing, MI 48824 (United States)

2017-06-01

Capacitive input couplers based on a 50 Ω coaxial transmission line are frequently used to transmit RF power to superconducting (SC) resonators operating in CW mode. It is well known that coaxial transmission lines are prone to multipacting phenomenon in a wide range of RF power level and operating frequency. The Facility for Rare Isotope Beams (FRIB) being constructed at Michigan State University includes two types of quarter wave SC resonators (QWR) operating at 80.5 MHz and two types of half wave SC resonators (HWR) operating at 322 MHz. As was reported in ref. [1] a capacitive input coupler used with HWRs was experiencing strong multipacting that resulted in a long conditioning time prior the cavity testing at design levels of accelerating fields. We have developed an insert into 50 Ω coaxial transmission line that provides opportunity to bias the RF coupler antenna and protect the amplifier from the bias potential in the case of breakdown in DC isolation. Two of such devices have been built and are currently used for the off-line testing of 8 HWRs installed in the cryomodule.

Topotactic oxidation pathway of ScTiO3 and high-temperature structure evolution of ScTiO3.5 and Sc4Ti3O12-type phases.

Science.gov (United States)

Shafi, Shahid P; Hernden, Bradley C; Cranswick, Lachlan M D; Hansen, Thomas C; Bieringer, Mario

2012-02-06

The novel oxide defect fluorite phase ScTiO(3.5) is formed during the topotactic oxidation of ScTiO(3) bixbyite. We report the oxidation pathway of ScTiO(3) and structure evolution of ScTiO(3.5), Sc(4)Ti(3)O(12), and related scandium-deficient phases as well as high-temperature phase transitions between room temperature and 1300 °Cusing in-situ X-ray diffraction. We provide the first detailed powder neutron diffraction study for ScTiO(3). ScTiO(3) crystallizes in the cubic bixbyite structure in space group Ia3 (206) with a = 9.7099(4) Å. The topotactic oxidation product ScTiO(3.5) crystallizes in an oxide defect fluorite structure in space group Fm3m (225) with a = 4.89199(5) Å. Thermogravimetric and differential thermal analysis experiments combined with in-situ X-ray powder diffraction studies illustrate a complex sequence of a topotactic oxidation pathway, phase segregation, and ion ordering at high temperatures. The optimized bulk synthesis for phase pure ScTiO(3.5) is presented. In contrast to the vanadium-based defect fluorite phases AVO(3.5+x) (A = Sc, In) the novel titanium analogue ScTiO(3.5) is stable over a wide temperature range. Above 950 °C ScTiO(3.5) undergoes decomposition with the final products being Sc(4)Ti(3)O(12) and TiO(2). Simultaneous Rietveld refinements against powder X-ray and neutron diffraction data showed that Sc(4)Ti(3)O(12) also exists in the defect fluorite structure in space group Fm3m (225) with a = 4.90077(4) Å. Sc(4)Ti(3)O(12) undergoes partial reduction in CO/Ar atmosphere to form Sc(4)Ti(3)O(11.69(2)).

CERN: SC-33

Energy Technology Data Exchange (ETDEWEB)

Anon.

1991-06-15

On 22 April a forward-looking CERN also looked back for a day, when the 'SC-33' event reviewed the achievements of CERN's first machine, the 600 MeV SynchroCyclotron (SC), which closed down on 17 December after 33 years of valiant service.

CERN: SC-33

International Nuclear Information System (INIS)

Anon.

1991-01-01

On 22 April a forward-looking CERN also looked back for a day, when the 'SC-33' event reviewed the achievements of CERN's first machine, the 600 MeV SynchroCyclotron (SC), which closed down on 17 December after 33 years of valiant service

S-C Mylonites

NARCIS (Netherlands)

Lister, G.S.; Snoke, A.W.

1984-01-01

Two types of foliations are commonly developed in mylonites and mylonitic rocks: (a) S-surfaces related to the accumulation of finite strain and (b) C-surfaces related to displacement discontinuities or zones of relatively high shear strain. There are two types of S-C mylonites. Type I S-C

Cavity Control and Cooling of Nanoparticles in High Vacuum

Science.gov (United States)

Millen, James

2016-05-01

Levitated systems are a fascinating addition to the world of optically-controlled mechanical resonators. It is predicted that nanoparticles can be cooled to their c.o.m. ground state via the interaction with an optical cavity. By freeing the oscillator from clamping forces dissipation and decoherence is greatly reduced, leading to the potential to produce long-lived, macroscopically spread, mechanical quantum states, allowing tests of collapse models and any mass limit of quantum physics. Reaching the low pressures required to cavity-cool to the ground state has proved challenging. Our approach is to cavity cool a beam of nanoparticles in high vacuum. We can cool the c.o.m. motion of nanospheres, and control the rotation of nanorods, with the potential to produce cold, aligned nanostructures. Looking forward, we will utilize novel microcavities to enhance optomechanical cooling, preparing particles in a coherent beam ideally suited to ultra-high mass interferometry at 107 a.m.u.

Determination of 46Sc in water

International Nuclear Information System (INIS)

Huo Bijun; Ji Zhaogang; Wang Juying

1985-01-01

Analytical procedures for the determination of 46 Sc in water is presented. 46 Sc in water is concentrated with Fe(OH) 3 ; Then 46 Sc is extracted with TBP and purified by precipitating it with Amygdalic Acid. Finally the precipitate is ignited into Sc 2 O 3 under 800 deg C and β-activity is counted. In this method chemical reeovery for Sc was (90.8 +- 2.8)% and radiochemical recovery for 46 Sc was (89.8 +- 3.8)%. Purification factors for some of the relevant Radionuclides ranged from 10 3 to 10 5

The effect of Sc additions on the microstructure and age hardening behaviour of as cast Al–Sc alloys

International Nuclear Information System (INIS)

Costa, S.; Puga, H.; Barbosa, J.; Pinto, A.M.P.

2012-01-01

Highlights: ► The Sc effect on the microstructure and ageing behaviour of Al–Sc alloys is studied. ► Cast into copper mould allows the elimination of solution heat treatment. ► Directly aged as cast alloys exhibits higher hardness and precipitation kinetics. ► Sc addition and optimised ageing result in an increase in Al–Sc mechanical properties. -- Abstract: The grain refinement effect and the ageing behaviour of Al–0.5 wt.% Sc, Al–0.7 wt.% Sc, and Al–1 wt.% Sc alloys are studied on the basis of optic microscopy (OM), scanning electron microscopy (SEM), X-ray diffraction (XRD) observations and hardness measurements. In Al–Sc alloys the higher grain refinement is observed for Sc contents greater than 0.5 wt.% accompanied by a notorious morphology modification, from coarse columnar grains to a fine perfect equiaxed structure. The as cast structures are characterised by a rich supersaturated solid solution in Sc, that promotes a great age hardening response at 250 °C and 300 °C. The age hardening curves also demonstrate a low overageing kinetics for all the alloys. Although the higher Sc content in solid solution for the alloys with 0.7 and 1 wt.% Sc, the age hardening response of all the Al–Sc alloys remains similar. The direct age hardening response of the as cast Al–0.5 wt.% Sc is shown to be greater than the solutionised and age hardened alloy.

Development of a movable plunger tuner for the high-power RF cavity for the PEP-II B-factory

International Nuclear Information System (INIS)

Schwarz, H.D.; Fant, K.; Judkins, J.G.

1997-05-01

A 10 cm diameter by 5 cm travel plunger tuner was developed for the PEP-II RF copper cavity system. The single cell cavity including the tuner is designed to operate up to 150 kW of dissipated RF power are specially placed 8.5 cm away from the inside wall of the cavity to avoid fundamental and higher order mode resonances. The spring fingers are made of dispersion-strengthened copper to accommodate relatively high heating. The design, alignment, testing and performance of the tuner is described

Superconducting RF Cavities Past, Present and Future

CERN Document Server

Chiaveri, Enrico

2003-01-01

In the last two decades many laboratories around the world, notably Argonne (ANL), TJNAF (formerly CEBAF), CERN, DESY and KEK, decided to develop the technology of superconducting (SC) accelerating cavities. The aim was either to increase the accelerator energy or to save electrical consumption or both. This technology has been used extensively in the operating machines showing good performances and strong reliability. At present, the technology using bulk niobium (Nb) or Nb coated on copper (Cu) is mature enough to be applied for many different applications, such as synchrotron light sources and spallation neutron drivers. Results, R&D work and future projects will be presented with emphasis on application to linear accelerators.

Solid-State NMR Spectroscopy Proves the Presence of Penta-coordinated Sc Sites in MIL-100(Sc).

Science.gov (United States)

Giovine, Raynald; Volkringer, Christophe; Ashbrook, Sharon E; Trébosc, Julien; McKay, David; Loiseau, Thierry; Amoureux, Jean-Paul; Lafon, Olivier; Pourpoint, Frédérique

2017-07-18

Advanced solid-state NMR methods and first-principles calculations demonstrate for the first time the formation of penta-coordinated scandium sites. These coordinatively unsaturated sites were shown during the thermal activation of scandium-based metal-organic frameworks (MOFs). A 45 Sc NMR experiment allows their specific observation in activated Sc 3 BTB 2 (H 3 BTB=1,3,5-tris(4-carboxyphenyl)benzene) and MIL-100(Sc) MOFs. The assignment of the ScO 5 groups is supported by the DFT calculations of NMR parameters. The presence of ScO 5 Lewis acid sites in MIL-100(Sc) explains furthermore its catalytic activity. The first NMR experiment to probe 13 C- 45 Sc distances is also introduced. This advanced solid-state NMR pulse sequence allows the demonstration of the shrinkage of the MIL-100(Sc) network when the activation temperature is raised. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Infectivity-associated PrP(Sc) and disease duration-associated PrP(Sc) of mouse BSE prions.

Science.gov (United States)

Miyazawa, Kohtaro; Okada, Hiroyuki; Masujin, Kentaro; Iwamaru, Yoshifumi; Yokoyama, Takashi

2015-01-01

Disease-related prion protein (PrP(Sc)), which is a structural isoform of the host-encoded cellular prion protein, is thought to be a causative agent of transmissible spongiform encephalopathies. However, the specific role of PrP(Sc) in prion pathogenesis and its relationship to infectivity remain controversial. A time-course study of prion-affected mice was conducted, which showed that the prion infectivity was not simply proportional to the amount of PrP(Sc) in the brain. Centrifugation (20,000 ×g) of the brain homogenate showed that most of the PrP(Sc) was precipitated into the pellet, and the supernatant contained only a slight amount of PrP(Sc). Interestingly, mice inoculated with the obtained supernatant showed incubation periods that were approximately 15 d longer than those of mice inoculated with the crude homogenate even though both inocula contained almost the same infectivity. Our results suggest that a small population of fine PrP(Sc) may be responsible for prion infectivity and that large, aggregated PrP(Sc) may contribute to determining prion disease duration.

First heavy ion beam tests with a superconducting multigap CH cavity

Science.gov (United States)

Barth, W.; Aulenbacher, K.; Basten, M.; Busch, M.; Dziuba, F.; Gettmann, V.; Heilmann, M.; Kürzeder, T.; Miski-Oglu, M.; Podlech, H.; Rubin, A.; Schnase, A.; Schwarz, M.; Yaramyshev, S.

2018-02-01

Very compact accelerating-focusing structures, as well as short focusing periods, high accelerating gradients and short drift spaces are strongly required for superconducting (sc) accelerator sections operating at low and medium energies for continuous wave (cw) heavy ion beams. To keep the GSI-super heavy element (SHE) program competitive on a high level and even beyond, a standalone sc cw linac (Helmholtz linear accelerator) in combination with the GSI high charge state injector (HLI), upgraded for cw operation, is envisaged. Recently the first linac section (financed by Helmholtz Institute Mainz (HIM) and GSI) as a demonstration of the capability of 217 MHz multigap crossbar H-mode structures (CH) has been commissioned and extensively tested with heavy ion beam from the HLI. The demonstrator setup reached acceleration of heavy ions up to the design beam energy. The required acceleration gain was achieved with heavy ion beams even above the design mass to charge ratio at high beam intensity and full beam transmission. This paper presents systematic beam measurements with varying rf amplitudes and phases of the CH cavity, as well as phase space measurements for heavy ion beams with different mass to charge ratio. The worldwide first and successful beam test with a superconducting multigap CH cavity is a milestone of the R&D work of HIM and GSI in collaboration with IAP in preparation of the HELIAC project and other cw-ion beam applications.

OXBench: A benchmark for evaluation of protein multiple sequence alignment accuracy

Directory of Open Access Journals (Sweden)

Searle Stephen MJ

2003-10-01

Full Text Available Abstract Background The alignment of two or more protein sequences provides a powerful guide in the prediction of the protein structure and in identifying key functional residues, however, the utility of any prediction is completely dependent on the accuracy of the alignment. In this paper we describe a suite of reference alignments derived from the comparison of protein three-dimensional structures together with evaluation measures and software that allow automatically generated alignments to be benchmarked. We test the OXBench benchmark suite on alignments generated by the AMPS multiple alignment method, then apply the suite to compare eight different multiple alignment algorithms. The benchmark shows the current state-of-the art for alignment accuracy and provides a baseline against which new alignment algorithms may be judged. Results The simple hierarchical multiple alignment algorithm, AMPS, performed as well as or better than more modern methods such as CLUSTALW once the PAM250 pair-score matrix was replaced by a BLOSUM series matrix. AMPS gave an accuracy in Structurally Conserved Regions (SCRs of 89.9% over a set of 672 alignments. The T-COFFEE method on a data set of families with http://www.compbio.dundee.ac.uk. Conclusions The OXBench suite of reference alignments, evaluation software and results database provide a convenient method to assess progress in sequence alignment techniques. Evaluation measures that were dependent on comparison to a reference alignment were found to give good discrimination between methods. The STAMP Sc Score which is independent of a reference alignment also gave good discrimination. Application of OXBench in this paper shows that with the exception of T-COFFEE, the majority of the improvement in alignment accuracy seen since 1985 stems from improved pair-score matrices rather than algorithmic refinements. The maximum theoretical alignment accuracy obtained by pooling results over all methods was 94

SC tuning fork

CERN Document Server

The tuning fork used to modulate the radiofrequency system of the synchro cyclotron (SC) from 1957 to 1973. This piece is an unused spare part. The SC was the 1st accelerator built at CERN. It operated from August 1957 until it was closed down at the end of 1990. In the SC the magnetic field did not change with time, and the particles were accelerated in successive pulses by a radiofrequency voltage of some 20kV which varied in frequency as they spiraled outwards towards the extraction radius. The frequency varied from 30MHz to about 17Mz in each pulse. The tuning fork vibrated at 55MHz in vacuum in an enclosure which formed a variable capacitor in the tuning circuit of the RF system, allowing the RF to vary over the appropriate range to accelerate protons from the centre of the macine up to 600Mev at extraction radius. In operation the tips of the tuning fork blade had an amplitude of movement of over 1 cm. The SC accelerator underwent extensive improvements from 1973 to 1975, including the installation of a...

Measurement for commercial exposives with SC-DSC test. Sangyoyo bakuhayaku no SC-DSC sokutei

Energy Technology Data Exchange (ETDEWEB)

Yabashi, H.; Wada, Y.; Hwang, D.; Akutsu, Y.; Tamura, M.; Yoshida, T. (The University of Tokyo, Tokyo (Japan). Faculty of Engineering); Matsuzawa, T. (Nippon Kayaku Co. Ltd., Tokyo (Japan))

1991-08-30

The sealed cell differential scanning calorimetry (SC-DSC) was sintroduced of commercial blasting explosives. As a series of testing the commercial blasting explosives in performance, an SC-DSC test was made to compare the critical detonability line with that resulting therefrom. From the result of SC-DSC measurement, the critical dilution rate was estimated of commercial blasting explosives to become without detonating propagation. As a result, all the explosives with exception of ANFO one were assumed to have a possibility of detonating propagation so that the ANFO explosive was known to be material, unable to exactly evaluate the detonability by the SC-DSC test. The explosion heat, then calculated by the REITP2 in order to assume how the reaction proceeded in the DSC cell, was compared with the reaction heat measured by the SC-DSC test. As a result, the calculated value was known to be almost equal to or slightly larger than the measured one. 15 refs., 4 figs., 2 tabs.

Alignment for new Subaru ring

International Nuclear Information System (INIS)

Zhang, Ch.; Matsui, S.; Hashimoto, S.

1999-01-01

The New SUBARU is a synchrotron light source being constructed at the SPring-8 site. The main facility is a 1.5 GeV electron storage ring that provides light beam in the region from VUV to soft X-ray using SPring-8's 1 GeV linac as an injector. The ring, with a circumference of about 119 meters, is composed of six bending cells. Each bending cell has two normal dipoles of 34 degree and one inverse dipole of -8 degree. The ring has six straight sections: two very long straight sections for a 11-m long undulator and an optical klystron, four short straight sections for a 2.3-m undulator, a super-conducting wiggler, rf cavity and injection, etc. The magnets of the storage ring are composed of 12 dipoles (BMs), 6 invert dipoles (BIs), 56 quadrupoles and 44 sextupoles, etc. For the magnet alignment, positions of the dipoles (the BMs and BIs) are determined by network survey method. The multipoles, which are mounted on girders between the dipoles, are aligned with a laser-CCD camera system. This article presents the methodology used to position the different components and particularly to assure the precise alignment of the multipoles. (authors)

Measuring the Dispersion in Laser Cavity Mirrors using White-Light Interferometry

Science.gov (United States)

2008-03-01

mirrors. Two AlGaInP (aluminum gallium indium phosphide ) diode lasers are aligned such that one is polarized vertically while one is polarized...linear crystals, where the index of refraction depends on beam intensity. Short pulses with high peak intensities are well 14 suited to induce the...MEASURING THE DISPERSION OF LASER CAVITY MIRRORS USING WHITE-LIGHT INTERFEROMETRY THESIS Allison S

HIE-Isolde: Commissioning and first results of the Mathilde system monitoring the positions of cavities and solenoids inside cryomodules

CERN Document Server

Kautzmann, Guillaume; Klumb, Francis; CERN. Geneva. ATS Department

2016-01-01

The new superconducting HIE-ISOLDE Linac replaced most of pre-existing REX ISOLDE facility at CERN. This upgrade involves the design, construction, installation and commissioning of 4 high-β cryomodules. Each high-β cryomodule houses five superconducting cavities and one superconducting solenoid. Beam-physics simulations show that the optimum linac working conditions are obtained when the main axes of the active components, located inside the cryostats, are aligned and permanently monitored on the REX Nominal Beam Line (NBL) within a precision of 0.3 mm for the cavities and 0.15 mm for the solenoids at one sigma level along directions perpendicular to the beam axis. The Monitoring and Alignment Tracking for HIE-ISOLDE (MATHILDE) system has been developed to fulfil the alignment and monitoring needs for components exposed to non-standard environmental conditions such as high vacuum or cryogenic temperatures. MATHILDE is based on opto-electronic sensors (HBCAM) observing, through high quality viewports, spher...

The Resilient Schools Consortium (RiSC): Linking Climate Literacy, Resilience Thinking and Service Learning

Science.gov (United States)

Branco, B. F.; Fano, E.; Adams, J.; Shon, L.; Zimmermann, A.; Sioux, H.; Gillis, A.

2017-12-01

Public schools and youth voices are largely absent from climate resilience planning and projects in New York City. Additionally, research shows that U.S. science teachers' understanding of climate science is lacking, hence there is not only an urgent need to train and support teachers on both the science and pedagogy of climate change, but to link climate literacy, resilience thinking and service learning in K-12 education. However, research on participation of students and teachers in authentic, civic-oriented experiences points to increased engagement and learning outcomes in science. The Resilient Schools Consortium (RiSC) Project will address all these needs through an afterschool program in six coastal Brooklyn schools that engages teachers and urban youth (grades 6-12), in school and community climate resilience assessment and project design. The RiSC climate curriculum, co-designed by New York City school teachers with Brooklyn College, the National Wildlife Federation, New York Sea Grant and the Science and Resilience Institute at Jamaica Bay, will begin by helping students to understand the difference between climate and weather. The curriculum makes extensive use of existing resources such as NOAA's Digital Coast and the Coastal Resilience Mapping Portal. Through a series of four modules over two school years, the six RiSC teams will; 1. explore and understand the human-induced drivers of climate change and, particularly, the significant climate and extreme weather related risks to their schools and surrounding communities; 2. complete a climate vulnerability assessment within the school and the community that is aligned to OneNYC - the city's resilience planning document; 3. design and execute a school-based resilience project; and 4. propose resilience guidelines for NYC Department of Education schools. At the end of each school year, the six RiSC teams will convene a RiSC summit with city officials and resilience practitioners to share ideas and

α-ScVSe2O8, β-ScVSe2O8, and ScVTe2O8: new quaternary mixed metal oxides composed of only second-order Jahn-Teller distortive cations.

Science.gov (United States)

Kim, Yeong Hun; Lee, Dong Woo; Ok, Kang Min

2013-10-07

Three new quaternary scandium vanadium selenium/tellurium oxides, α-ScVSe2O8, β-ScVSe2O8, and ScVTe2O8 have been synthesized through hydrothermal and standard solid-state reactions. Although all three reported materials are stoichiometrically similar, they exhibit different crystal structures: α-ScVSe2O8 has a three-dimensional framework structure consisting of ScO6, VO6, and SeO3 groups. β-ScVSe2O8 reveals another three-dimensional framework composed of ScO7, VO5, and SeO3 polyhedra. ScVTe2O8 shows a layered structure with ScO6, VO4, and TeO4 polyhedra. Interestingly, the constituent cations, that is, Sc(3+), V(5+), Se(4+), and Te(4+) are all in a distorted coordination environment attributable to second-order Jahn-Teller (SOJT) effects. Complete characterizations including infrared spectroscopy, elemental analyses, thermal analyses, dipole moment calculation, and the magnitudes of out-of-center distortions for the compounds are reported. Transformation reactions suggest that α-ScVSe2O8 may change to β-ScVSe2O8, and then to Sc2(SeO3)3·H2O under hydrothermal conditions.

Status of the mechanical design of the 650 MHz cavities for Project X

Energy Technology Data Exchange (ETDEWEB)

Barbanotti, S.; Grimm, C.; Champion, M.; Foley, M.; Ginsburg, C.M.; Gonin, I.; Peterson, T.; Ristori, L.; Yakovlev, V.; /Fermilab

2011-03-01

In the high-energy section of the Project X Linac, acceleration of H{sup -} ions takes place in superconducting cavities operating at 650 MHz. Two families of five-cell elliptical cavities are planned: beta = 0.61 and beta = 0.9. A specific feature of the Project X Linac is low beam loading, and thus, low bandwidth and higher sensitivity to microphonics. Efforts to optimize the mechanical design of the cavities to improve their mechanical stability in response to the helium bath pressure fluctuations will be presented. These efforts take into account constraints such as cost and ease of fabrication. Also discussed will be the overall design status of the cavities and their helium jackets. The proposed design of the 3 GeV Project X superconducting (SC) Linac employs 650 MHz five-cell elliptical cavities to accelerate 1.0 mA of average H-beam current in the 160-3000 MeV energy range. The 650 MHz region of the Linac is divided into two sections with two different geometric phase velocity factors: beta = 0.61 to cover the 160-520 MeV range and beta = 0.9 to cover the 520-3000 MeV range. Approximately 40 beta = 0.61 and 150 beta = 0.9 cavities are currently planned for the project. An R&D program is in progress at FNAL, in collaboration with TJNAF and India, to develop the 650 MHz cavities for the proposed Linac design. This R&D program includes the design and fabrication of several beta = 0.61 and beta = 0.9 single-cell prototypes for evaluation prior to production of the five-cell cavities. FNAL has contracted AES to fabricate the beta = 0.9 prototypes, while TJNAF is building beta = 0.61 prototypes of their own design. In the remainder of this paper we will restrict our discussion to the five-cell beta = 0.9 cavities.

Beam position diagnostics with higher order modes in third harmonic superconducting accelerating cavities

CERN Document Server

Zhang, P; Baboi, Nicoleta

2012-01-01

Higher order modes (HOM) are electromagnetic resonant fields. They can be excited by an electron beam entering an accelerating cavity, and constitute a component of the wakefield. This wakefield has the potential to dilute the beam quality and, in the worst case, result in a beam-break-up instability. It is therefore important to ensure that these fields are well suppressed by extracting energy through special couplers. In addition, the effect of the transverse wakefield can be reduced by aligning the beam on the cavity axis. This is due to their strength depending on the transverse offset of the excitation beam. For suitably small offsets the dominant components of the transverse wakefield are dipole modes, with a linear dependence on the transverse offset of the excitation bunch. This fact enables the transverse beam position inside the cavity to be determined by measuring the dipole modes extracted from the couplers, similar to a cavity beam position monitor (BPM), but requires no additional vacuum instrum...

Continuous-wave optically pumped green perovskite vertical-cavity surface-emitter

KAUST Repository

Alias, Mohd Sharizal

2017-09-11

We report an optically pumped green perovskite vertical-cavity surface-emitter operating in continuous-wave (CW) with a power density threshold of ~89 kW/cm2. The device has an active region of CH3NH3PbBr3 embedded in a dielectric microcavity; this feat was achieved with a combination of optimal spectral alignment of the optical cavity modes with the perovskite optical gain, an adequate Q-factor of the microcavity, adequate thermal stability, and improved material quality with a smooth, passivated, and annealed thin active layer. Our results signify a way towards efficient CW perovskite emitter operation and electrical injection using low-cost fabrication methods for addressing monolithic optoelectronic integration and lasing in the green gap.

Two anionically derivatized scandium oxoselenates(IV): ScF[SeO3] and Sc2O2[SeO3

Science.gov (United States)

Greiner, Stefan; Chou, Sheng-Chun; Schleid, Thomas

2017-02-01

Scandium fluoride oxoselenate(IV) ScF[SeO3] and scandium oxide oxoselenate(IV) Sc2O2[SeO3] could be synthesized through solid-state reactions. ScF[SeO3] was obtained phase-pure, by reacting mixtures of Sc2O3, ScF3 and SeO2 (molar ratio: 1:1:3) together with CsBr as fluxing agent in corundum crucibles embedded into evacuated glassy silica ampoules after firing at 700 °C for seven days. Sc2O2[SeO3] first emerged as by-product during the attempts to synthesize ScCl[SeO3] following aforementioned synthesis route and could later be reproduced from appropriate Sc2O3/SeO3 mixtures. ScF[SeO3] crystallizes monoclinically in space group P21/m with a=406.43(2), b =661.09(4), c=632.35(4) pm, β=93.298(3)° and Z=2. Sc2O2[SeO3] also crystallizes in the monoclinic system, but in space group P21/n with a=786.02(6), b=527.98(4), c=1086.11(8) pm, β=108.672(3)° for Z=4. The crystal structures of both compounds are strongly influenced by the stereochemically active lone pairs of the ψ1-tetrahedral [SeO3]2- anions. They also show partial structures, where the derivatizing F- or O2- anions play an important role. For ScF[SeO3] chains of the composition 2+∞ 1[FS c 2 / 2 ] form from connected [FSc2]5+ dumbbells, while [OSc3]7+ pyramids and [OSc4]10+ tetrahedra units are condensed to layers according to 2+ ∞ 2[O2Sc2 ] in Sc2O2[SeO3].

Compensation of native donor doping in ScN: Carrier concentration control and p-type ScN

Science.gov (United States)

Saha, Bivas; Garbrecht, Magnus; Perez-Taborda, Jaime A.; Fawey, Mohammed H.; Koh, Yee Rui; Shakouri, Ali; Martin-Gonzalez, Marisol; Hultman, Lars; Sands, Timothy D.

2017-06-01

Scandium nitride (ScN) is an emerging indirect bandgap rocksalt semiconductor that has attracted significant attention in recent years for its potential applications in thermoelectric energy conversion devices, as a semiconducting component in epitaxial metal/semiconductor superlattices and as a substrate material for high quality GaN growth. Due to the presence of oxygen impurities and native defects such as nitrogen vacancies, sputter-deposited ScN thin-films are highly degenerate n-type semiconductors with carrier concentrations in the (1-6) × 1020 cm-3 range. In this letter, we show that magnesium nitride (MgxNy) acts as an efficient hole dopant in ScN and reduces the n-type carrier concentration, turning ScN into a p-type semiconductor at high doping levels. Employing a combination of high-resolution X-ray diffraction, transmission electron microscopy, and room temperature optical and temperature dependent electrical measurements, we demonstrate that p-type Sc1-xMgxN thin-film alloys (a) are substitutional solid solutions without MgxNy precipitation, phase segregation, or secondary phase formation within the studied compositional region, (b) exhibit a maximum hole-concentration of 2.2 × 1020 cm-3 and a hole mobility of 21 cm2/Vs, (c) do not show any defect states inside the direct gap of ScN, thus retaining their basic electronic structure, and (d) exhibit alloy scattering dominating hole conduction at high temperatures. These results demonstrate MgxNy doped p-type ScN and compare well with our previous reports on p-type ScN with manganese nitride (MnxNy) doping.

Investigation of Sc(3) state in nonaqueous solutions by the 45Sc NMR method of high permission

International Nuclear Information System (INIS)

Buslaev, Yu.A.; Kirakosyan, G.A.; Tarasov, V.P.

1980-01-01

The ScCl 3 + CH 3 CN and ScCl 3 + KNCS + CH 3 CN solutions have been studied by a high-resolution NMR 45 Sc method. It has been estimated that in acetonitrile solutions, with competing ligands of Cl - and NCS - being available, hexacoordination Sc(3) complexes of various compositions are formed, and solvent molecules also take part in formation of the coordination sphere of scandium. Chemical shifts in NMR 45 Sc signals depend linearly on the number of chlor- or NCS - ions bound to scandium(3). This made it possible to determine the value of chemical shifts in signals of all 28 potential complexes formed in a system with three competing ligands

Novel methods in track-based alignment to correct for time-dependent distortions of the ATLAS Inner Detector

CERN Document Server

Estrada Pastor, Oscar; The ATLAS collaboration

2017-01-01

ATLAS is a multipurpose experiment at the LHC proton-proton collider. Its physics goals require high resolution, unbiased measurement of all charged particle kinematic parameters. These critically depend on the layout and performance of the tracking system and the quality of its offline alignment. For the LHC Run II, the system has been upgraded with the installation of a new pixel layer, the Insertable B-layer (IBL). Offline track alignment of the ATLAS tracking system has to deal with about 700,000 degrees of freedom (DoF) defining its geometrical parameters, representing a considerable numerical challenge in terms of both CPU time and precision. An outline of the track based alignment approach and its implementation within the ATLAS software will be presented. Special attention will be paid to describe the techniques allowing to pinpoint and eliminate track parameters biases due to alignment. During Run-II, ATLAS Inner Detector Alignment framework has been adapted and upgraded to correct very short time sc...

Development of standardized radioactive 46Sc solution

International Nuclear Information System (INIS)

Du Hongshan; Jia Zhang; Yu Yiguang; Sun Naiyao

1988-01-01

A method of preparation of standardized radioactive 46 Sc solution is developed. The separation of 46 Sc, the composition of 46 Sc solution and its stability, and radioactivity measurement of 46 Sc are systematically studied. The results obtained in the study and in the applications in many laboratories have shown that our method is effective and reliable

Hierarchical creep cavity formation in an ultramylonite and implications for phase mixing

Science.gov (United States)

Gilgannon, James; Fusseis, Florian; Menegon, Luca; Regenauer-Lieb, Klaus; Buckman, Jim

2017-12-01

Establishing models for the formation of well-mixed polyphase domains in ultramylonites is difficult because the effects of large strains and thermo-hydro-chemo-mechanical feedbacks can obscure the transient phenomena that may be responsible for domain production. We use scanning electron microscopy and nanotomography to offer critical insights into how the microstructure of a highly deformed quartzo-feldspathic ultramylonite evolved. The dispersal of monomineralic quartz domains in the ultramylonite is interpreted to be the result of the emergence of synkinematic pores, called creep cavities. The cavities can be considered the product of two distinct mechanisms that formed hierarchically: Zener-Stroh cracking and viscous grain-boundary sliding. In initially thick and coherent quartz ribbons deforming by grain-size-insensitive creep, cavities were generated by the Zener-Stroh mechanism on grain boundaries aligned with the YZ plane of finite strain. The opening of creep cavities promoted the ingress of fluids to sites of low stress. The local addition of a fluid lowered the adhesion and cohesion of grain boundaries and promoted viscous grain-boundary sliding. With the increased contribution of viscous grain-boundary sliding, a second population of cavities formed to accommodate strain incompatibilities. Ultimately, the emergence of creep cavities is interpreted to be responsible for the transition of quartz domains from a grain-size-insensitive to a grain-size-sensitive rheology.

Knowledge insufficient: the management of haemoglobin SC disease.

Science.gov (United States)

Pecker, Lydia H; Schaefer, Beverly A; Luchtman-Jones, Lori

2017-02-01

Although haemoglobin SC (HbSC) accounts for 30% of sickle cell disease (SCD) in the United States and United Kingdom, evidence-based guidelines for genotype specific management are lacking. The unique pathology of HbSC disease is complex, characterized by erythrocyte dehydration, intracellular sickling and increased blood viscosity. The evaluation and treatment of patients with HbSC is largely inferred from studies of SCD consisting mostly of haemoglobin SS (HbSS) patients. These studies are underpowered to allow definitive conclusions about HbSC. We review the pathophysiology of HbSC disease, including known and potential differences between HbSS and HbSC, and highlight knowledge gaps in HbSC disease management. Clinical and translational research is needed to develop targeted treatments and to validate management recommendations for efficacy, safety and impact on quality of life for people with HbSC. © 2016 John Wiley & Sons Ltd.

SC-FDMA for mobile communications

CERN Document Server

Abd El-Samie, Fathi E

2013-01-01

SC-FDMA for Mobile Communications examines Single-Carrier Frequency Division Multiple Access (SC-FDMA). Explaining this rapidly evolving system for mobile communications, it describes its advantages and limitations and outlines possible solutions for addressing its current limitations. The book explores the emerging trend of cooperative communication with SC-FDMA and how it can improve the physical layer security. It considers the design of distributed coding schemes and protocols for wireless relay networks where users cooperate to send their data to the destination. Supplying you with the re

Precipitation in cold-rolled Al-Sc-Zr and Al-Mn-Sc-Zr alloys prepared by powder metallurgy

KAUST Repository

Vlach, Martin

2013-12-01

The effects of cold-rolling on thermal, mechanical and electrical properties, microstructure and recrystallization behaviour of the AlScZr and AlMnScZr alloys prepared by powder metallurgy were studied. The powder was produced by atomising in argon with 1% oxygen and then consolidated by hot extrusion at 350 C. The electrical resistometry and microhardness together with differential scanning calorimetry measurements were compared with microstructure development observed by transmission and scanning electron microscopy, X-ray diffraction and electron backscatter diffraction. Fine (sub)grain structure developed and fine coherent Al3Sc and/or Al3(Sc,Zr) particles precipitated during extrusion at 350 C in the alloys studied. Additional precipitation of the Al3Sc and/or Al3(Sc,Zr) particles and/or their coarsening was slightly facilitated by the previous cold rolling. The presence of Sc,Zr-containing particles has a significant antirecrystallization effect that prevents recrystallization at temperatures minimally up to 420 C. The precipitation of the Al6Mn- and/or Al 6(Mn,Fe) particles of a size ~ 1.0 μm at subgrain boundaries has also an essential antirecrystallization effect and totally suppresses recrystallization during 32 h long annealing at 550 C. The texture development of the alloys seems to be affected by high solid solution strengthening by Mn. The precipitation of the Mn-containing alloy is highly enhanced by a cold rolling. The apparent activation energy of the Al3Sc particles formation and/or coarsening and that of the Al6Mn and/or Al 6(Mn,Fe) particle precipitation in the powder and in the compacted alloys were determined. The cold deformation has no effect on the apparent activation energy values of the Al3Sc-phase and the Al 6Mn-phase precipitation. © 2013 Elsevier Inc.

Precipitation in cold-rolled Al-Sc-Zr and Al-Mn-Sc-Zr alloys prepared by powder metallurgy

KAUST Repository

Vlach, Martin; Stulí ková , Ivana; Smola, Bohumil; Kekule, Tomá š; Kudrnová , Hana; Daniš, Stanislav; Gemma, Ryota; Očená šek, Vladivoj; Má lek, Jaroslav; Tanprayoon, Dhritti; Neubert, Volkmar

2013-01-01

The effects of cold-rolling on thermal, mechanical and electrical properties, microstructure and recrystallization behaviour of the AlScZr and AlMnScZr alloys prepared by powder metallurgy were studied. The powder was produced by atomising in argon with 1% oxygen and then consolidated by hot extrusion at 350 C. The electrical resistometry and microhardness together with differential scanning calorimetry measurements were compared with microstructure development observed by transmission and scanning electron microscopy, X-ray diffraction and electron backscatter diffraction. Fine (sub)grain structure developed and fine coherent Al3Sc and/or Al3(Sc,Zr) particles precipitated during extrusion at 350 C in the alloys studied. Additional precipitation of the Al3Sc and/or Al3(Sc,Zr) particles and/or their coarsening was slightly facilitated by the previous cold rolling. The presence of Sc,Zr-containing particles has a significant antirecrystallization effect that prevents recrystallization at temperatures minimally up to 420 C. The precipitation of the Al6Mn- and/or Al 6(Mn,Fe) particles of a size ~ 1.0 μm at subgrain boundaries has also an essential antirecrystallization effect and totally suppresses recrystallization during 32 h long annealing at 550 C. The texture development of the alloys seems to be affected by high solid solution strengthening by Mn. The precipitation of the Mn-containing alloy is highly enhanced by a cold rolling. The apparent activation energy of the Al3Sc particles formation and/or coarsening and that of the Al6Mn and/or Al 6(Mn,Fe) particle precipitation in the powder and in the compacted alloys were determined. The cold deformation has no effect on the apparent activation energy values of the Al3Sc-phase and the Al 6Mn-phase precipitation. © 2013 Elsevier Inc.

Band structure of the quaternary Heusler alloys ScMnFeSn and ScFeCoAl

Science.gov (United States)

Shanthi, N.; Teja, Y. N.; Shaji, Shephine M.; Hosamani, Shashikala; Divya, H. S.

2018-04-01

In our quest for materials with specific applications, a theoretical study plays an important role in predicting the properties of compounds. Heusler alloys or compounds are the most studied in this context. More recently, a lot of quaternary Heusler compounds are investigated for potential applications in fields like Spintronics. We report here our preliminary study of the alloys ScMnFeSn and ScFeCoAl, using the ab-initio linear muffin-tin orbital method within the atomic sphere approximation (LMTO-ASA). The alloy ScMnFeSn shows perfect half-metallicity, namely, one of the spins shows a metallic behaviour and the other spin shows semi-conducting behaviour. Such materials find application in devices such as the spin-transfer torque random access memory (STT-MRAM). In addition, the alloy ScMnFeSn is found to have an integral magnetic moment of 4 µB, as predicted by the Slater-Pauling rule. The alloy ScFeCoAl does not show half-metallicity.

On losses caused in RF cavities by longitudinal electric fields

International Nuclear Information System (INIS)

Halbritter, J.

1976-02-01

Rf modes with large longitudinal electric fields (div E vector unequal to 0) at the cavity wall systematically show worse rf properties than modes with div E vector identical with 0; e.g. enlarged rf residual losses. While magnetic residual losses R sub(res) proportional f 2 are due to uncharged inhomogeneities in the oxide coating the metal, the electric residual losses R sub(orthogonal) occur via charged states in the oxide: the recharging of those states by tunnel exchange causes excitation across the energy gap of the superconductor yielding residual losses at high rf field strengths. The interaction of E sub(orthogonal) with the charges generate (longitudinal) phonons showing up as contribution to R sub(orthogonal). The resulting R sub(orthogonal) increases with E sub(orthogonal) and is nearly independent of frequency f, indicating the importance of R sub(orthogonal) for low frequency sc cavities, especially at high field strengths. In addition R sub(orthogonal) can account for the observed large residual losses of strip line modes in narrow junctions and joints between superconductors. (orig.) [de

Performance of a reentrant cavity beam position monitor

Directory of Open Access Journals (Sweden)

Claire Simon

2008-08-01

Full Text Available The beam-based alignment and feedback systems, essential operations for the future colliders, require high resolution beam position monitors (BPMs. In the framework of the European CARE/SRF program, a reentrant cavity BPM with its associated electronics was developed by the CEA/DSM/Irfu in collaboration with DESY. The design, the fabrication, and the beam test of this monitor are detailed within this paper. This BPM is designed to be inserted in a cryomodule, work at cryogenic temperature in a clean environment. It has achieved a resolution better than 10  μm and has the possibility to perform bunch to bunch measurements for the x-ray free electron laser (X-FEL and the International Linear Collider (ILC. Its other features are a small size of the rf cavity, a large aperture (78 mm, and an excellent linearity. A first prototype of a reentrant cavity BPM was installed in the free electron laser in Hamburg (FLASH, at Deutsches Elektronen-Synchrotron (DESY and demonstrated its operation at cryogenic temperature inside a cryomodule. The second, installed, also, in the FLASH linac to be tested with beam, measured a resolution of approximately 4  μm over a dynamic range ±5  mm in single bunch.

Performance of a reentrant cavity beam position monitor

International Nuclear Information System (INIS)

Simon, C.; Luong, M.; Chel, S.; Napoly, O.; Novo, J.; Roudier, D.; Rouviere, N.; Baboi, N.; Mildner, N.; Nolle, D.

2008-01-01

The beam-based alignment and feedback systems, essential operations for the future colliders, require high resolution beam position monitors (BPMs). In the framework of the European CARE/SRF program, a reentrant cavity BPM with its associated electronics was developed by the CEA/DSM/Irfu in collaboration with DESY. The design, the fabrication, and the beam test of this monitor are detailed within this paper. This BPM is designed to be inserted in a cryo-module, work at cryogenic temperature in a clean environment. It has achieved a resolution better than 10 μm and has the possibility to perform bunch to bunch measurements for the X-ray free electron laser (X-FEL) and the International Linear Collider (ILC). Its other features are a small size of the rf cavity, a large aperture (78 mm), and an excellent linearity. A first prototype of a reentrant cavity BPM was installed in the free electron laser in Hamburg (FLASH), at Deutsches Elektronen-Synchrotron (DESY) and demonstrated its operation at cryogenic temperature inside a cryo-module. The second, installed, also, in the FLASH linac to be tested with beam, measured a resolution of approximately 4 μm over a dynamic range ± 5 mm in single bunch. (authors)

Performance of a reentrant cavity beam position monitor

Science.gov (United States)

Simon, Claire; Luong, Michel; Chel, Stéphane; Napoly, Olivier; Novo, Jorge; Roudier, Dominique; Rouvière, Nelly; Baboi, Nicoleta; Mildner, Nils; Nölle, Dirk

2008-08-01

The beam-based alignment and feedback systems, essential operations for the future colliders, require high resolution beam position monitors (BPMs). In the framework of the European CARE/SRF program, a reentrant cavity BPM with its associated electronics was developed by the CEA/DSM/Irfu in collaboration with DESY. The design, the fabrication, and the beam test of this monitor are detailed within this paper. This BPM is designed to be inserted in a cryomodule, work at cryogenic temperature in a clean environment. It has achieved a resolution better than 10μm and has the possibility to perform bunch to bunch measurements for the x-ray free electron laser (X-FEL) and the International Linear Collider (ILC). Its other features are a small size of the rf cavity, a large aperture (78 mm), and an excellent linearity. A first prototype of a reentrant cavity BPM was installed in the free electron laser in Hamburg (FLASH), at Deutsches Elektronen-Synchrotron (DESY) and demonstrated its operation at cryogenic temperature inside a cryomodule. The second, installed, also, in the FLASH linac to be tested with beam, measured a resolution of approximately 4μm over a dynamic range ±5mm in single bunch.

Status report on CERN activities aiming at the production of sputter-coated copper superconducting RF cavities for LEP

International Nuclear Information System (INIS)

Benvenuti, C.; Bloess, D.; Chiaveri, E.; Hilleret, N.; Minestrini, M.; Weingarten, W.

1990-01-01

To upgrade LEP energy above 55 GeV, the first step will consist in installing 32 SC cavities of 352 MHz frequency at Point 2 of the machine. This operation will be carried out in steps and should be completed by the end of 1991. It has been decided that 8 of the 32 cavities will be Nb coated copper cavities, the crucial part of which (i.e. the cavity proper) will be manufactured and coated at CERN. For the time being, 4 of these 8 cavities have been prepared. They present Q 0 values at low field of about 10 10 , while at the specified operating field of 5 MV/m their Q 0 range between 5 and 7 x 10 9 . In order to carry out assembly, coating and rinsing of cavities in better (i.e. cleaner) conditions, an experimental hall is being prepared, which will become operational after summer 1989, such as to be used for the manufacturing of the second batch of 4 coated cavities. In parallel with this main activity, some work is also being devoted to the study of coatings of higher T c materials, namely NbTiN. Due to the higher T c , these new coatings should present a lower BCS RF resistivity, a necessary condition to obtain higher Q 0 values. The first cavity coated so far with NbTiN (a single cell cavity of 500 MHz frequency) gave encouraging results, which however are not better than what was obtained with a Nb film. (author)

The colours of Hubble Sc galaxy nuclei

International Nuclear Information System (INIS)

Iskudaryan, S.G.

1975-01-01

The colorimetric data on the nuclei of the Sc galaxies are given. Comparison of the following parameters: color of a nucleus, integral color of a galaxy, Byurakan class, and spectral type of normal spirals gives the possibility to conclude: (1) The colors of the nuclei of the Sc galaxies have a high dispersion in its values. In all Byurakan classes the galaxies with intensely red and blue nuclei occur; (2) Some Sc galaxies exhibit a discrepancy between the spectral and morphological types. The results of colorimetry of nuclei indicate that almost all such Sc galaxies have intensely red nuclei which, naturally, provide for these late spectral types. It can be assumed that the intensely red color of the nuclei of such Sc galaxies is a result of a new type of activity of these nuclei; and (3) some Sc galaxies show the characteristics of the Markarian objects

The measurement of the optical cavity length for the infrared free electron laser

International Nuclear Information System (INIS)

Curtis, C.J.; Dahlberg, J.C.; Oren, W.A.; Tremblay, K.J.

1999-01-01

One of the final tasks involved in the alignment of the newly constructed Free Electron Laser at the Thomas Jefferson National Accelerator Facility was to accurately measure the length between two mirrors which make up the optical cavity. This presentation examines the survey techniques and equipment assembled in order to complete these measurements, together with the possible sources of error, and the accuracy achieved. (authors)

Anion photoelectron spectroscopy of germanium and tin clusters containing a transition- or lanthanide-metal atom; MGe(n)- (n = 8-20) and MSn(n)- (n = 15-17) (M = Sc-V, Y-Nb, and Lu-Ta).

Science.gov (United States)

Atobe, Junko; Koyasu, Kiichirou; Furuse, Shunsuke; Nakajima, Atsushi

2012-07-14

The electronic properties of germanium and tin clusters containing a transition- or lanthanide-metal atom from group 3, 4, or 5, MGe(n) (M = Sc, Ti, V, Y, Zr, Nb, Lu, Hf, and Ta) and MSn(n) (M = Sc, Ti, Y. Zr, and Hf), were investigated by anion photoelectron spectroscopy at 213 nm. In the case of the group 3 elements Sc, Y, and Lu, the threshold energy of electron detachment of MGe(n)(-) exhibits local maxima at n = 10 and 16, while in the case of the group 4 elements Ti, Zr, and Hf, it exhibits a local minimum only at n = 16, associated with the presence of a small bump in the spectrum. A similar behavior is observed for MSn(n)(-) around n = 16, and these electronic characteristics of MGe(n) and MSn(n) are closely related to those of MSi(n). Compared to MSi(n), however, the larger cavity size of a Ge(n) cage allows metal atom encapsulation at a smaller size n. A cooperative effect between the electronic and geometric structures of clusters with a large cavity of Ge(16) or Sn(16) is discussed together with the results of experiments that probe their geometric stability via their reactivity to H(2)O adsorption.

Stability study of the higher order mode beam position monitors at the Accelerating cavities at FLASH

CERN Document Server

Shi, L; Jones., R M

2014-01-01

erating cavities at FLASH linac, DESY, are equipped with electronics for beam position monitoring, which are based on HOM signals from special couplers. These monitors provide the beam position without additional vacuum components and at low cost. Moreover, they can be used to align the beam in the cavities to reduce the HOM effects on the beam. However, the HOMBPM (Higher Order Mode based Beam Position Monitor) shows an instability problem over time. In this paper, we will present the status of studies on this issue. Several methods are utilized to calibrate the HOMBPMs. These methods include DLR (Direct Linear Regression), and SVD (Singular Value Decomposition). We found that SVD generally is more suitable for HOMBPM calibration. We focus on the HOMBPMs at 1.3 GHz cavities. Techniques developed here are applicable to 3.9 ...

Saccharomyces cerevisiae Differential Functionalization of Presumed ScALT1 and ScALT2 Alanine Transaminases Has Been Driven by Diversification of Pyridoxal Phosphate Interactions

Directory of Open Access Journals (Sweden)

Erendira Rojas-Ortega

2018-05-01

Full Text Available Saccharomyces cerevisiae arose from an interspecies hybridization (allopolyploidiza-tion, followed by Whole Genome Duplication. Diversification analysis of ScAlt1/ScAlt2 indicated that while ScAlt1 is an alanine transaminase, ScAlt2 lost this activity, constituting an example in which one of the members of the gene pair lacks the apparent ancestral physiological role. This paper analyzes structural organization and pyridoxal phosphate (PLP binding properties of ScAlt1 and ScAlt2 indicating functional diversification could have determined loss of ScAlt2 alanine transaminase activity and thus its role in alanine metabolism. It was found that ScAlt1 and ScAlt2 are dimeric enzymes harboring 67% identity and intact conservation of the catalytic residues, with very similar structures. However, tertiary structure analysis indicated that ScAlt2 has a more open conformation than that of ScAlt1 so that under physiological conditions, while PLP interaction with ScAlt1 allows the formation of two tautomeric PLP isomers (enolimine and ketoenamine ScAlt2 preferentially forms the ketoenamine PLP tautomer, indicating a modified polarity of the active sites which affect the interaction of PLP with these proteins, that could result in lack of alanine transaminase activity in ScAlt2. The fact that ScAlt2 forms a catalytically active Schiff base with PLP and its position in an independent clade in “sensu strictu” yeasts suggests this protein has a yet undiscovered physiological function.

Saccharomyces cerevisiae Differential Functionalization of Presumed ScALT1 and ScALT2 Alanine Transaminases Has Been Driven by Diversification of Pyridoxal Phosphate Interactions

Science.gov (United States)

Rojas-Ortega, Erendira; Aguirre-López, Beatriz; Reyes-Vivas, Horacio; González-Andrade, Martín; Campero-Basaldúa, Jose C.; Pardo, Juan P.; González, Alicia

2018-01-01

Saccharomyces cerevisiae arose from an interspecies hybridization (allopolyploidiza-tion), followed by Whole Genome Duplication. Diversification analysis of ScAlt1/ScAlt2 indicated that while ScAlt1 is an alanine transaminase, ScAlt2 lost this activity, constituting an example in which one of the members of the gene pair lacks the apparent ancestral physiological role. This paper analyzes structural organization and pyridoxal phosphate (PLP) binding properties of ScAlt1 and ScAlt2 indicating functional diversification could have determined loss of ScAlt2 alanine transaminase activity and thus its role in alanine metabolism. It was found that ScAlt1 and ScAlt2 are dimeric enzymes harboring 67% identity and intact conservation of the catalytic residues, with very similar structures. However, tertiary structure analysis indicated that ScAlt2 has a more open conformation than that of ScAlt1 so that under physiological conditions, while PLP interaction with ScAlt1 allows the formation of two tautomeric PLP isomers (enolimine and ketoenamine) ScAlt2 preferentially forms the ketoenamine PLP tautomer, indicating a modified polarity of the active sites which affect the interaction of PLP with these proteins, that could result in lack of alanine transaminase activity in ScAlt2. The fact that ScAlt2 forms a catalytically active Schiff base with PLP and its position in an independent clade in “sensu strictu” yeasts suggests this protein has a yet undiscovered physiological function. PMID:29867852

The ternary systems Sc-Sm(Dy)-Si at 870 K

International Nuclear Information System (INIS)

Kotur, B.Ya.; Mokra, I.Ya.; Toporinskij, A.Ya.

1991-01-01

Isothermal cross sections of the ternary systems Sc-Sm-Si and Sc-Dy-Si at 870 K have been plotted. Investigation of scandium and disprosium in ternary systems have been examined by X-ray diffraction and microstructure analysis. Besides literary data on binary systems Sc-Si, Sm-Si, Dy-Si have been used. Formation of limited (Sc-Sm-Si, Sc-Dy-Si) and continuous (Sc-Dy-Si) solid solutions based on bisilicides of Sc and Sm(Dy) is discovered. Two and five ternary compounds in Sc-Sm-Si and Sc-Dy-Si systems have been determined and their crystal structure has been established. When investigating of Sc-(rare earth element)-Si ternary systems and should take into account the specific interaction of scandium and samarium with REE

Construction and characterization of external cavity diode lasers for atomic physics.

Science.gov (United States)

Hardman, Kyle S; Bennetts, Shayne; Debs, John E; Kuhn, Carlos C N; McDonald, Gordon D; Robins, Nick

2014-04-24

Since their development in the late 1980s, cheap, reliable external cavity diode lasers (ECDLs) have replaced complex and expensive traditional dye and Titanium Sapphire lasers as the workhorse laser of atomic physics labs. Their versatility and prolific use throughout atomic physics in applications such as absorption spectroscopy and laser cooling makes it imperative for incoming students to gain a firm practical understanding of these lasers. This publication builds upon the seminal work by Wieman, updating components, and providing a video tutorial. The setup, frequency locking and performance characterization of an ECDL will be described. Discussion of component selection and proper mounting of both diodes and gratings, the factors affecting mode selection within the cavity, proper alignment for optimal external feedback, optics setup for coarse and fine frequency sensitive measurements, a brief overview of laser locking techniques, and laser linewidth measurements are included.

Hydride vapor phase epitaxy growth of GaN, InGaN, ScN, and ScAIN

NARCIS (Netherlands)

Bohnen, T.

2010-01-01

Chemical vapor deposition (CVD); hydride vapor phase epitaxy (HVPE); gallium nitride (GaN); indium gallium nitride (InGaN); scandium nitride (ScN); scandium aluminum nitride (ScAlN); semiconductors; thin films; nanowires; III nitrides; crystal growth - We studied the HVPE growth of different III

Activities on cryostats and SRF cavities at the I.P.N. Orsay laboratory

International Nuclear Information System (INIS)

Buelher, S.; Caruette, A.; Fouaidy, M.; Junquera, T.

1993-01-01

The main effort of the SRF community at Orsay during the last five years was concentrated on the MACSE project (study, construction, assembly and test of 3 cryostats), participation to the TESLA project and R and D activities in close collaboration with the Saclay SRF group. 3 major topics are outlined and briefly discussed: cryogenics, scanning surface thermometers for diagnostics on SRF cavities and thermal behaviour analysis of HOM couplers. The main results obtained in this frame since the 5th SC workshop at Hamburg in 1991 are presented. (authors) 12 refs., 17 figs., 6 tabs

Ultimate internal pressure capacity assessment of SC structure

International Nuclear Information System (INIS)

Park, Hyungkui; Choi, Inkil

2013-01-01

An SC structure applied to a containment building can be quite effective. However, an SC structure cannot be applied to a containment building, because its internal pressure resistance performance has not been verified. The containment building, which undergoes ultimate internal pressure, resists the internal pressure through a pre-stress tendon. It is hard to apply a tendon to an SC structure because of its structural characteristics. Therefore, the internal pressure resistance performance of the SC structure itself should be ensured to apply it to a structure with internal pressure resistance. In this study, the suitability of an SC structure as a substitution for the tendon of a pressure resistant structure was evaluated. A containment structure model was used in this study, because it was representative structures that resistance of ultimate internal pressure be required. In this study, a nonlinear analysis was performed to evaluate and compare the behaviors of tendon model and SC structure model. By comparing the internal pressure-displacement according to the structure type, the stability of SC structure model was assessed

Ab-initio studies of the Sc adsorption and the ScN thin film formation on the GaN(000-1)-(2 × 2) surface

International Nuclear Information System (INIS)

Guerrero-Sánchez, J.; Sánchez-Ochoa, F.; Cocoletzi, Gregorio H.; Rivas-Silva, J.F.; Takeuchi, Noboru

2013-01-01

First principles total energy calculations have been performed to investigate the initial stages of the Sc adsorption and ScN thin film formation on the GaN(000-1)-(2 × 2) surface. Studies are done within the periodic density functional theory as implemented in the PWscf code of the Quantum ESPRESSO package. The Sc adsorption at high symmetry sites results in the bridge site as the most stable structure. When a Sc monolayer is deposited above the surface the T4 site results as the most stable geometry. The Sc migration into the first Ga monolayer induces the Ga displaced ad-atom to be adsorbed at the T4-2 site. A ScN bilayer may be obtained under the Ga monolayer. Finally a ScN bilayer may be formed in the wurtzite phase above the surface. The formation energy plots show that in the moderate Ga-rich conditions we obtain the formation of a ScN bilayer under the gallium monolayer. However at N-rich conditions the formation of ScN bilayer above the surface is the most favorable structure. We report the density of states to explain the electronic structure of the most favorable geometries. - Highlights: • Studies of the initial stages in the formation of Sc and ScN structures on GaN • In the adsorption of Sc on the GaN the Br site is the most favorable geometry. • When a Sc replaces a Ga of the first monolayer the displaced Ga occupies a T4-2 site. • For Ga-rich conditions there is formation of ScN under the Ga monolayer. • In N-rich conditions there is formation of ScN in the wurtzite phase

Implementation of the environment management system within SC Aedificia Carpati S.A

Energy Technology Data Exchange (ETDEWEB)

Tanislav, A.; Rizea, D. [S.C Aedificia Carpati S.A, Bucharest (Romania)

2000-07-01

The implementation process followed by S.C Aedificia Carpati S.A for the Environment Management System (EMS) was explained. It took into account the requirements of sustainable development and environmental protection. Established in 1992, the company is active in the fields of monument restoration and the production of aluminium furnishings, marble, stone, wood processing, pre-cast concrete and concrete production. The implementation of EMS was based on aspects of: (1) human, physical and financial resources, (2) EMS alignment and integration, (3) consciousness and motivation of the environment protection, (4)knowledge, skills and training, (5) operational management, (6) preparation and reaction to critical situations, and (7) practical aspects regarding EMS within the company. The company practices wastes recycling of marble, plywood floors, walls and other demolition partitions and light concrete.

Alignment sensing and control in advanced LIGO

International Nuclear Information System (INIS)

Barsotti, L; Evans, M; Fritschel, P

2010-01-01

The advanced LIGO detectors are currently in their final design stage, and the installation phase will start at the end of 2010: they will have about 10 times better sensitivity than initial LIGO, with a sensitive band ranging from 10 Hz to 10 kHz. As compared with previous LIGO detectors, there will be increased complexity in the optical configuration, improved seismic isolation system and significantly higher power circulating in the arm cavities. In the new detectors, the control of the angular orientation of the mirrors will be particularly challenging. The advanced LIGO (aLIGO) mirrors need to have a residual angular motion of the order of 1 nrad RMS in order to achieve high sensitivity. In the high power regime, the torque induced by radiation pressure effects will be comparable with the restoring torque of the mirror suspension, such that we must think of the opto-mechanical response, instead of just the mechanical response. These modifications have to be considered in order to design the control strategy for keeping the mirrors well aligned. Moreover, to meet the sensitivity target the alignment control noise coupled to the gravitational-wave channel must be well below 6x10 -18 m/√Hz at 10 Hz. We developed a model of the alignment sensing and control scheme of aLIGO which takes into account radiation pressure effects and meets the noise target.

A Compact Microwave Microfluidic Sensor Using a Re-Entrant Cavity.

Science.gov (United States)

Hamzah, Hayder; Abduljabar, Ali; Lees, Jonathan; Porch, Adrian

2018-03-19

A miniaturized 2.4 GHz re-entrant cavity has been designed, manufactured and tested as a sensor for microfluidic compositional analysis. It has been fully evaluated experimentally with water and common solvents, namely methanol, ethanol, and chloroform, with excellent agreement with the expected behaviour predicted by the Debye model. The sensor's performance has also been assessed for analysis of segmented flow using water and oil. The samples' interaction with the electric field in the gap region has been maximized by aligning the sample tube parallel to the electric field in this region, and the small width of the gap (typically 1 mm) result in a highly localised complex permittivity measurement. The re-entrant cavity has simple mechanical geometry, small size, high quality factor, and due to the high concentration of electric field in the gap region, a very small mode volume. These factors combine to result in a highly sensitive, compact sensor for both pure liquids and liquid mixtures in capillary or microfluidic environments.

Performance of a high resolution cavity beam position monitor system

Science.gov (United States)

Walston, Sean; Boogert, Stewart; Chung, Carl; Fitsos, Pete; Frisch, Joe; Gronberg, Jeff; Hayano, Hitoshi; Honda, Yosuke; Kolomensky, Yury; Lyapin, Alexey; Malton, Stephen; May, Justin; McCormick, Douglas; Meller, Robert; Miller, David; Orimoto, Toyoko; Ross, Marc; Slater, Mark; Smith, Steve; Smith, Tonee; Terunuma, Nobuhiro; Thomson, Mark; Urakawa, Junji; Vogel, Vladimir; Ward, David; White, Glen

2007-07-01

It has been estimated that an RF cavity Beam Position Monitor (BPM) could provide a position measurement resolution of less than 1 nm. We have developed a high resolution cavity BPM and associated electronics. A triplet comprised of these BPMs was installed in the extraction line of the Accelerator Test Facility (ATF) at the High Energy Accelerator Research Organization (KEK) for testing with its ultra-low emittance beam. The three BPMs were each rigidly mounted inside an alignment frame on six variable-length struts which could be used to move the BPMs in position and angle. We have developed novel methods for extracting the position and tilt information from the BPM signals including a robust calibration algorithm which is immune to beam jitter. To date, we have demonstrated a position resolution of 15.6 nm and a tilt resolution of 2.1 μrad over a dynamic range of approximately ±20 μm.

Energy Levels and Radiative Rates for Transitions in F-like Sc XIII and Ne-like Sc XII and Y XXX

Science.gov (United States)

Aggarwal, Kanti

2018-05-01

Energy levels, radiative rates and lifetimes are reported for F-like Sc~XIII and Ne-like Sc~XII and Y~XXX for which the general-purpose relativistic atomic structure package ({\\sc grasp}) has been adopted. For all three ions limited data exist in the literature but comparisons have been made wherever possible to assess the accuracy of the calculations. In the present work the lowest 102, 125 and 139 levels have been considered for the respective ions. Additionally, calculations have also been performed with the flexible atomic code ({\\sc fac}) to (particularly) confirm the accuracy of energy levels.

Axisymmetric particle-in-cell simulations of diamagnetic-cavity formation in vacuum

International Nuclear Information System (INIS)

Gisler, G.

1989-01-01

Axisymmetric simulations of the expansion of a hot plasma suddenly introduced into a vacuum containing a weak magnetic field were performed using an electromagnetic particle-in-cell code. Both uniform and gradient fields have been used, with the simulation axis along the principle field direction. The formation of a diamagnetic cavity requires an initial plasma β > 1; as the expansion proceeds, β diminishes, and the field eventually recovers. The maximum spatial extent of the cavity and its duration can be obtained from simple dynamical considerations. Field-aligned ion acceleration behind the electron front is observed in all field geometries and strengths. In the case of expansion into a divergent field, the plasma is found to move down the field gradient by ambipolar diffusion. These simulations are relevant to active release experiments in the Earth's magnetosphere, to pellet ablation experiments, and to the naturally occurring diamagnetic bubbles observed at the Earth's foreshock

Construction and Characterization of External Cavity Diode Lasers for Atomic Physics

Science.gov (United States)

Hardman, Kyle S.; Bennetts, Shayne; Debs, John E.; Kuhn, Carlos C. N.; McDonald, Gordon D.; Robins, Nick

2014-01-01

Since their development in the late 1980s, cheap, reliable external cavity diode lasers (ECDLs) have replaced complex and expensive traditional dye and Titanium Sapphire lasers as the workhorse laser of atomic physics labs1,2. Their versatility and prolific use throughout atomic physics in applications such as absorption spectroscopy and laser cooling1,2 makes it imperative for incoming students to gain a firm practical understanding of these lasers. This publication builds upon the seminal work by Wieman3, updating components, and providing a video tutorial. The setup, frequency locking and performance characterization of an ECDL will be described. Discussion of component selection and proper mounting of both diodes and gratings, the factors affecting mode selection within the cavity, proper alignment for optimal external feedback, optics setup for coarse and fine frequency sensitive measurements, a brief overview of laser locking techniques, and laser linewidth measurements are included. PMID:24796259

Cyclotron production of {sup 44}Sc for clinical application

Energy Technology Data Exchange (ETDEWEB)

Krajewski, S.; Bilewicz, A. [Institute of Nuclear Chemistry and Technology, Warsaw (Poland); Cydzik, I. [Institute of Nuclear Chemistry and Technology, Warsaw (Poland); European Commission Joint Research Center, Ispra (Italy). Inst. for Health and Consumer Protection; Warsaw Univ. (Poland). Heavy Ion Lab.; Abbas, K. [European Commission Joint Research Center, Ispra (Italy). Institute for Transuranium Elements; Bulgheroni, A.; Simonelli, F.; Holzwarth, U. [European Commission Joint Research Center, Ispra (Italy). Inst. for Health and Consumer Protection

2013-08-01

{sup 44} is a promising {beta}{sup +}-emitter for molecular imaging with intermediate half-life of 4 h. Due to the chemical similarity of Sc{sup 3+} to the Lu{sup 3+} and Y{sup 3+} cations, {sup 44}Sc-DOTA bioconjugates are expected to demonstrate similar properties in vivo as the {sup 177}Lu- and {sup 90}Y-bioconjugates, what is important in planning the radionuclide therapy. {sup 44}Sc can be obtained from the {sup 44}Ti/{sup 44}Sc generator. An alternative method for {sup 44}Sc production can be the irradiation of {sup 44}Ca target at small cyclotrons. The aim of our work was to optimize the parameters of {sup 44}CaCO{sub 3} irradiation and to develop a simple procedure for {sup 44}Sc separation from the calcium target. For optimization study, {sup 44}CaCO{sub 3} targets were irradiated by protons in the energy range of 5.6-17.5 MeV with 9 MeV being found to be the best energy for {sup 44}Ca irradiations. A simple and fast separation procedure of {sup 44}Sc from calcium target was developed using chelating resin Chelex 100. DOTATATE conjugate was successfully radiolabelled with high yield at elevated temperature using the produced {sup 44}Sc. While {sup 44}CaCO{sub 3} is relatively expensive, the cost of {sup 44}Sc-DOTATATE production can be reduced by target recovery. Due to low proton energy required to produce GBq activity level of {sup 44}Sc, the availability of {sup 44}Sc radioisotope could be enhanced to open new opportunities for applications in medical imaging. (orig.)

Radiation Protection Section (SC/SL/RP)

CERN Document Server

2006-01-01

We should like to inform you that the Radiation Protection Section (SC/SL/RP) located on the Prévessin site has moved from Building 865 (ground floor) to new premises in Wing A of Building 892 (second floor). Telephone numbers remain the same. SC/SL/RP section

Superconducting Super Collider Laboratory coupled-cavity linac mechanical design

International Nuclear Information System (INIS)

Starling, W.J.; Cain, T.

1992-01-01

A collaboration between the Superconducting Super Collider Laboratory (SSCL) and the Los Alamos National Laboratory (LANL) for the engineering and mechanical design of the SSCL Coupled-Cavity Linac (CCL) has yielded an innovative example of the well known side coupled-cavity type of linear accelerator. The SSCL CCL accelerates an H - beam from 70 MeV to 600 MeV with an rf cavity structure consisting of eight tanks in each of nine modules for a total length of about 112 meters. Magnetically-coupled bridge couplers transfer power from tank to tank within a module. A single rf power input is located at the center bridge coupler of each module. The bridge couplers permit placement along the beam line of combined function focusing/steering electromagnets and diagnostic pods for beam instrumentation. Each tank and bridge coupler is rf frequency stabilized, nominally to 1,283 MHz, by water pumped through integral water passages. Air isolation grooves surround the water passages at each braze joint so that water-to-vacuum interfaces are avoided. Each tank is supported by adjustable spherical bearing rod end struts to permit alignment and accommodate thermal expansion and contraction of the rf structure. Tank struts, electromagnet/diagnostic pod support frames, vacuum manifolds and utilities are all mounted to a girder-and-leg support stand running the full length of the CCL. (Author) tab., fig

Bright single photon source based on self-aligned quantum dot–cavity systems

DEFF Research Database (Denmark)

Maier, Sebastian; Gold, Peter; Forchel, Alfred

2014-01-01

We report on a quasi-planar quantum-dot-based single-photon source that shows an unprecedented high extraction efficiency of 42% without complex photonic resonator geometries or post-growth nanofabrication. This very high efficiency originates from the coupling of the photons emitted by a quantum...... dot to a Gaussian shaped nanohill defect that naturally arises during epitaxial growth in a self-aligned manner. We investigate the morphology of these defects and characterize the photonic operation mechanism. Our results show that these naturally arising coupled quantum dot-defects provide a new...... avenue for efficient (up to 42% demonstrated) and pure (g2(0) value of 0.023) single-photon emission....

Cyclotron production of {sup 43}Sc for PET imaging

Energy Technology Data Exchange (ETDEWEB)

Walczak, Rafał [Institute of Nuclear Chemistry and Technology, Dorodna 16, 03-195 Warsaw (Poland); Krajewski, Seweryn [Synektik S.A., Research and Development Center, Warsaw (Poland); Szkliniarz, Katarzyna [Department of Nuclear Physics, University of Silesia, Katowice (Poland); Sitarz, Mateusz [Heavy Ion Laboratory, University of Warsaw, Warsaw (Poland); Abbas, Kamel [Nuclear Security Unit, Joint Research Centre, Institute for Transuranium Elements, European Commission, Ispra (Italy); Choiński, Jarosław; Jakubowski, Andrzej; Jastrzębski, Jerzy [Heavy Ion Laboratory, University of Warsaw, Warsaw (Poland); Majkowska, Agnieszka [Institute of Nuclear Chemistry and Technology, Dorodna 16, 03-195 Warsaw (Poland); Simonelli, Federica [Nuclear Decommissioning Unit, Joint Research Centre, Ispra Site Management Directorate, European Commission, Ispra (Italy); Stolarz, Anna; Trzcińska, Agnieszka [Heavy Ion Laboratory, University of Warsaw, Warsaw (Poland); Zipper, Wiktor [Department of Nuclear Physics, University of Silesia, Katowice (Poland); Bilewicz, Aleksander [Institute of Nuclear Chemistry and Technology, Dorodna 16, 03-195 Warsaw (Poland)

2015-12-04

Recently, significant interest in {sup 44}Sc as a tracer for positron emission tomography (PET) imaging has been observed. Unfortunately, the co-emission by {sup 44}Sc of high-energy γ rays (E{sub γ} = 1157, 1499 keV) causes a dangerous increase of the radiation dose to the patients and clinical staff. However, it is possible to produce another radionuclide of scandium—{sup 43}Sc—having properties similar to {sup 44}Sc but is characterized by much lower energy of the concurrent gamma emissions. This work presents the production route of {sup 43}Sc by α irradiation of natural calcium, its separation and purification processes, and the labeling of [DOTA,Tyr3] octreotate (DOTATATE) bioconjugate. Natural CaCO{sub 3} and enriched [{sup 40}Ca]CaCO{sub 3} were irradiated with alpha particles for 1 h in an energy range of 14.8–30 MeV at a beam current of 0.5 or 0.25 μA. In order to find the optimum method for the separation of {sup 43}Sc from irradiated calcium targets, three processes previously developed for {sup 44}Sc were tested. Radiolabeling experiments were performed with DOTATATE radiobioconjugate, and the stability of the obtained {sup 43}Sc-DOTATATE was tested in human serum. Studies of {sup nat}CaCO{sub 3} target irradiation by alpha particles show that the optimum alpha particle energies are in the range of 24–27 MeV, giving 102 MBq/μA/h of {sup 43}Sc radioactivity which creates the opportunity to produce several GBq of {sup 43}Sc. The separation experiments performed indicate that, as with {sup 44}Sc, due to the simplicity of the operations and because of the chemical purity of the {sup 43}Sc obtained, the best separation process is when UTEVA resin is used. The DOTATATE conjugate was labeled by the obtained {sup 43}Sc with a yield >98 % at elevated temperature. Tens of GBq activities of {sup 43}Sc of high radionuclidic purity can be obtainable for clinical applications by irradiation of natural calcium with an alpha beam.

Surface temperature measurements on superconducting cavities in superfluid helium

International Nuclear Information System (INIS)

Fouaidy, T.; Junquera, T.; Caruette, A.

1991-01-01

Two thermometry systems have been developed: a scanning thermometer system routinely used for the 1.5 GHz monocell cavity studies and a fixed thermometer array used to investigate spatial surface resistance distribution on various SC removable endplates of a cylindrical TE011mode cavity. Thermometers used in these systems are thermally insulated from the surrounding HeII bath by an epoxy housing ('epoxy'thermometers). Accurate calibration of the fixed thermometers was conducted by using different test cells and the experimental results were compared to model calculations performed with a finite element computational code. Measured thermometer efficiency and linearity are in good agreement with numerical results. Some typical temperature maps of different Nb samples obtained with the TE011 array (40 epoxy thermometers) are discussed. On the basis of numerical modelling results, a new type of thermometer with an improved efficiency has been designed. The thermal insulation against Helium II has been drastically improved by placing the sensitive part of the thermometer in a small vacuum jacket ('vacuum' thermometers). Two main goals have been reached with the first prototypes: improved efficiency by a factor of 2.5 - 3, and a bath temperature dependence of the thermal response in good agreement with the expected Kapitza conductance behaviour. Fitting experimental results with numerical modelling data, allow us to estimate the Kapitza conductance. The obtained values are in good agreement with the previous results reported by several authors using a different measurement method. The 'vacuum' thermometers are currently used on the TE011 mode cavity with Nb and NbTiN plates and the first results are presented

Spinning cylinder experiments SC-I and SC-II: A review of results and analyses provided to the FALSIRE project

International Nuclear Information System (INIS)

Morland, E.; Sherry, A.H.

1993-01-01

A series of six large-scale experiments have been carried out at AEA Technology using the Spinning Cylinder test facility. Results from two of those experiments (SC-I and SC-II) have been provided to Project FALSIRE and are reviewed in this paper. The Spinning Cylinder tests were carried out using hollow cylinders of 1.4m outer diameter, 0.2m wall thickness and 1.3m length, containing full-length axial defects and fabricated from a modified A508 Class 3 steel. The first Spinning Cylinder test (SC-I) was an investigation of stable ductile growth induced via mechanical (primary) loading and under conditions of contained yielding. Mechanical loading was provided in the hoop direction by rotating the cylinder about its major axis within an enclosed oven. The second test (SC-II) investigated stable ductile growth under severe thermal shock (secondary) loading again under conditions of contained yielding. In this case thermal shock was produced by spraying cold water on the inside surface of the heated cylinder whilst it was rotating. For each experiment, results are presented in terms of a number of variables, eg. crack growth, temperature, stress, strain and applied K and J. In addition, an overview of the analyses of the FALSIRE Phase-1 report is also presented with respect to test SC-I and SC-II. 4 refs., 14 figs., 13 tabs

Effective single chain antibody (scFv) concentrations in vivo via adenoviral vector mediated expression of secretory scFv

NARCIS (Netherlands)

Arafat, WO; Gomez-Navarro, J; Buchsbaum, DJ; Xiang, J; Casado, E; Barker, SD; Mahasreshti, PJ; Haisma, HJ; Barnes, MN; Siegal, GP; Alvarez, RD; Hemminki, A; Nettelbeck, DM; Curiel, DT

Single chain antibodies (scFv) represent powerful interventional agents for the achievement of targeted therapeutics. The practical utility of these agents have been limited, however, by difficulties related to production of recombinant scFv and the achievement of effective and sustained levels of

Hemoglobin C, S-C, and E Diseases

Science.gov (United States)

... quickly than others, resulting in chronic anemia. Hemoglobin C disease Hemoglobin C disease occurs mostly in blacks. ... a common complication of hemoglobin C disease. Hemoglobin S-C disease Hemoglobin S-C disease occurs in people who ...

Integrated fiber-mirror ion trap for strong ion-cavity coupling

International Nuclear Information System (INIS)

Brandstätter, B.; Schüppert, K.; Casabone, B.; Friebe, K.; Stute, A.; Northup, T. E.; McClung, A.; Schmidt, P. O.; Deutsch, C.; Reichel, J.; Blatt, R.

2013-01-01

We present and characterize fiber mirrors and a miniaturized ion-trap design developed to integrate a fiber-based Fabry-Perot cavity (FFPC) with a linear Paul trap for use in cavity-QED experiments with trapped ions. Our fiber-mirror fabrication process not only enables the construction of FFPCs with small mode volumes, but also allows us to minimize the influence of the dielectric fiber mirrors on the trapped-ion pseudopotential. We discuss the effect of clipping losses for long FFPCs and the effect of angular and lateral displacements on the coupling efficiencies between cavity and fiber. Optical profilometry allows us to determine the radii of curvature and ellipticities of the fiber mirrors. From finesse measurements, we infer a single-atom cooperativity of up to 12 for FFPCs longer than 200 μm in length; comparison to cavities constructed with reference substrate mirrors produced in the same coating run indicates that our FFPCs have similar scattering losses. We characterize the birefringence of our fiber mirrors, finding that careful fiber-mirror selection enables us to construct FFPCs with degenerate polarization modes. As FFPCs are novel devices, we describe procedures developed for handling, aligning, and cleaning them. We discuss experiments to anneal fiber mirrors and explore the influence of the atmosphere under which annealing occurs on coating losses, finding that annealing under vacuum increases the losses for our reference substrate mirrors. X-ray photoelectron spectroscopy measurements indicate that these losses may be attributable to oxygen depletion in the mirror coating. Special design considerations enable us to introduce a FFPC into a trapped ion setup. Our unique linear Paul trap design provides clearance for such a cavity and is miniaturized to shield trapped ions from the dielectric fiber mirrors. We numerically calculate the trap potential in the absence of fibers. In the experiment additional electrodes can be used to compensate

Alignment of Duke free electron laser storage ring and optical beam delivery system

International Nuclear Information System (INIS)

Emamian, M.; Hower, N.

1999-01-01

Duke Free Electron Laser Laboratory (DFELL) hosts a 1.1 GeV electron beam storage ring facility which is capable of generating beams in the range of nearly monochromatic gamma rays to high peak power infra red (IR) laser. In this report specifications and procedures for alignment of OK-4 /Duke storage ring FEL wiggler and optical cavity mirrors will be discussed. The OK-4 FEL lasing has demonstrated a series of world record in the last few years. In August of this year the OK-4 FEL successfully commissioned to laser at 193.7 nm. Also in this article, alignment of the γ-ray and UV optical beam delivery system that is currently in progress will be described. (authors)

A Novel Manufacturing Process for Compact, Low-Weight and Flexible Ultra-Wideband Cavity Backed Textile Antennas

Directory of Open Access Journals (Sweden)

Dries Van Baelen

2018-01-01

Full Text Available A novel manufacturing procedure for the fabrication of ultra-wideband cavity-backed substrate integrated waveguide antennas on textile substrates is proposed. The antenna cavity is constructed using a single laser-cut electrotextile patch, which is folded around the substrate. Electrotextile slabs protruding from the laser-cut patch are then vertically folded and glued to form the antenna cavity instead of rigid metal tubelets to implement the vertical cavity walls. This approach drastically improves mechanical flexibility, decreases the antenna weight to slightly more than 1 g and significantly reduces alignment errors. As a proof of concept, a cavity-backed substrate integrated waveguide antenna is designed and realized for ultra-wideband operation in the [5.15–5.85] GHz band. Antenna performance is validated in free space as well as in two on body measurement scenarios. Furthermore, the antenna’s figures of merit are characterized when the prototype is bent at different curvature radii, as commonly encountered during deployment on the human body. Also the effect of humidity content on antenna performance is studied. In all scenarios, the realized antenna covers the entire operating frequency band, meanwhile retaining a stable radiation pattern with a broadside gain above 5 dBi, and a radiation efficiency of at least 70%.

Status on RF superconductivity at the institute for high energy physics

International Nuclear Information System (INIS)

Sevryukova, L.M.

2003-01-01

The development of SC cavities started at the Institute for High Energy Physics in September 1980 when the group of technology and study of SC cavities of the Research Institute of Nuclear Physics at Tomsk Polytechnic Institute moved there. At first the group worked at the Linear Accelerator Division, then later, in March 1993 the Federate Problem Laboratory for Technology and Study of the superconducting cavities of the Russian Atomic Ministry was founded at IHEP. The main goal of the SC cavity investigation is to study and develop the suppression methods for emission effects and conditions for thermomagnetic breakdown creation to increase the accelerating fields at SC cavities; also developing the experimental equipment to answer this goal. In this report the following items are enlightened in short: 1. Study and development of methods to suppress emission effects in SC cavities; 2. Study and development of methods to increase the threshold of the thermomagnetic breakdown. 3. Study of new materials and technologies. 4. SVAAP (SC accelerator for the applied purposes) project development. (author)

INCREASING OF THE EXPRESSION OF RECOMBINANT scFv-ANTIBODIES EFFICIENCY

Directory of Open Access Journals (Sweden)

O.V. Galkin

2017-10-01

Full Text Available Obtaining single-chain variable fragments (scFv of recombinant antibodies in E. coli cells is often associated with numerous problems causing low yields or inactive conformation of the product. The aim of this work was to study the influence of staphylococcal protein A fragment fused with scFv antibodies (SpA-tag on the efficiency of expression of final product. Examination of scFv antibodies of different origin and specificity has shown that in similar expression systems fused scFv is synthesized in much higher quantities than free scFv. Furthermore, the scFv antibodies in fused form retained their antigen-binding properties and the SpA fragment the ability to bind other immunoglobulins. Thus, the proposed strategy can be considered effective in improving the efficiency of scFv-antibodies production in E. coli cells.

Aligning the unalignable: bacteriophage whole genome alignments.

Science.gov (United States)

Bérard, Sèverine; Chateau, Annie; Pompidor, Nicolas; Guertin, Paul; Bergeron, Anne; Swenson, Krister M

2016-01-13

In recent years, many studies focused on the description and comparison of large sets of related bacteriophage genomes. Due to the peculiar mosaic structure of these genomes, few informative approaches for comparing whole genomes exist: dot plots diagrams give a mostly qualitative assessment of the similarity/dissimilarity between two or more genomes, and clustering techniques are used to classify genomes. Multiple alignments are conspicuously absent from this scene. Indeed, whole genome aligners interpret lack of similarity between sequences as an indication of rearrangements, insertions, or losses. This behavior makes them ill-prepared to align bacteriophage genomes, where even closely related strains can accomplish the same biological function with highly dissimilar sequences. In this paper, we propose a multiple alignment strategy that exploits functional collinearity shared by related strains of bacteriophages, and uses partial orders to capture mosaicism of sets of genomes. As classical alignments do, the computed alignments can be used to predict that genes have the same biological function, even in the absence of detectable similarity. The Alpha aligner implements these ideas in visual interactive displays, and is used to compute several examples of alignments of Staphylococcus aureus and Mycobacterium bacteriophages, involving up to 29 genomes. Using these datasets, we prove that Alpha alignments are at least as good as those computed by standard aligners. Comparison with the progressive Mauve aligner - which implements a partial order strategy, but whose alignments are linearized - shows a greatly improved interactive graphic display, while avoiding misalignments. Multiple alignments of whole bacteriophage genomes work, and will become an important conceptual and visual tool in comparative genomics of sets of related strains. A python implementation of Alpha, along with installation instructions for Ubuntu and OSX, is available on bitbucket (https://bitbucket.org/thekswenson/alpha).

Effects of self-calibration of intrinsic alignment on cosmological parameter constraints from future cosmic shear surveys

International Nuclear Information System (INIS)

Yao, Ji; Ishak, Mustapha; Lin, Weikang; Troxel, Michael

2017-01-01

Intrinsic alignments (IA) of galaxies have been recognized as one of the most serious contaminants to weak lensing. These systematics need to be isolated and mitigated in order for ongoing and future lensing surveys to reach their full potential. The IA self-calibration (SC) method was shown in previous studies to be able to reduce the GI contamination by up to a factor of 10 for the 2-point and 3-point correlations. The SC method does not require the assumption of an IA model in its working and can extract the GI signal from the same photo-z survey offering the possibility to test and understand structure formation scenarios and their relationship to IA models. In this paper, we study the effects of the IA SC mitigation method on the precision and accuracy of cosmological parameter constraints from future cosmic shear surveys LSST, WFIRST and Euclid. We perform analytical and numerical calculations to estimate the loss of precision and the residual bias in the best fit cosmological parameters after the self-calibration is performed. We take into account uncertainties from photometric redshifts and the galaxy bias. We find that the confidence contours are slightly inflated from applying the SC method itself while a significant increase is due to the inclusion of the photo-z uncertainties. The bias of cosmological parameters is reduced from several-σ, when IA is not corrected for, to below 1-σ after SC is applied. These numbers are comparable to those resulting from applying the method of marginalizing over IA model parameters despite the fact that the two methods operate very differently. We conclude that implementing the SC for these future cosmic-shear surveys will not only allow one to efficiently mitigate the GI contaminant but also help to understand their modeling and link to structure formation.

Effects of self-calibration of intrinsic alignment on cosmological parameter constraints from future cosmic shear surveys

Energy Technology Data Exchange (ETDEWEB)

Yao, Ji; Ishak, Mustapha; Lin, Weikang [Department of Physics, The University of Texas at Dallas, Dallas, TX 75080 (United States); Troxel, Michael, E-mail: jxy131230@utdallas.edu, E-mail: mxi054000@utdallas.edu, E-mail: wxl123830@utdallas.edu, E-mail: michael.a.troxel@gmail.com [Department of Physics, Ohio State University, Columbus, OH 43210 (United States)

2017-10-01

Intrinsic alignments (IA) of galaxies have been recognized as one of the most serious contaminants to weak lensing. These systematics need to be isolated and mitigated in order for ongoing and future lensing surveys to reach their full potential. The IA self-calibration (SC) method was shown in previous studies to be able to reduce the GI contamination by up to a factor of 10 for the 2-point and 3-point correlations. The SC method does not require the assumption of an IA model in its working and can extract the GI signal from the same photo-z survey offering the possibility to test and understand structure formation scenarios and their relationship to IA models. In this paper, we study the effects of the IA SC mitigation method on the precision and accuracy of cosmological parameter constraints from future cosmic shear surveys LSST, WFIRST and Euclid. We perform analytical and numerical calculations to estimate the loss of precision and the residual bias in the best fit cosmological parameters after the self-calibration is performed. We take into account uncertainties from photometric redshifts and the galaxy bias. We find that the confidence contours are slightly inflated from applying the SC method itself while a significant increase is due to the inclusion of the photo-z uncertainties. The bias of cosmological parameters is reduced from several-σ, when IA is not corrected for, to below 1-σ after SC is applied. These numbers are comparable to those resulting from applying the method of marginalizing over IA model parameters despite the fact that the two methods operate very differently. We conclude that implementing the SC for these future cosmic-shear surveys will not only allow one to efficiently mitigate the GI contaminant but also help to understand their modeling and link to structure formation.

A Many-Atom Cavity QED System with Homogeneous Atom-Cavity Coupling

OpenAIRE

Lee, Jongmin; Vrijsen, Geert; Teper, Igor; Hosten, Onur; Kasevich, Mark A.

2013-01-01

We demonstrate a many-atom-cavity system with a high-finesse dual-wavelength standing wave cavity in which all participating rubidium atoms are nearly identically coupled to a 780-nm cavity mode. This homogeneous coupling is enforced by a one-dimensional optical lattice formed by the field of a 1560-nm cavity mode.

High performance electronics for alignment regulation on the CLIC 30GHz modules

International Nuclear Information System (INIS)

Carrica, D.; Coosemans, W.; Pittin, R.

1999-01-01

CERN is studying a linear collider (CLIC) to obtain electron-positron collisions with centre-of-mass energies in the TeV range. To demonstrate the feasibility of CLIC, a test facility (CTF2) is being constructed. CTF2 consists of 4 identical modules, each 1.4 m long module consists of 2 linac with a girder and a doublet or a triplet quadrupole. Girders are elements that support mechanically the cavities of the accelerator while the main objective of the quadrupole is to focus particle beams. The alignment system has 2 principal utilities. The first is to pre-align the elements to make the beam pass through the aperture and produce signals in beam position monitors. In respect to these signals the girders and the quadrupoles are moved for making the definitive alignment. The second utility is to maintain the elements in this position. The alignment control system of CTF2 must regulate the position of the girders and quadrupoles with a precision < 10 μm. In fact an accuracy of 1 μ has been obtained on CTF2. Thanks to its flexibility and its simplicity, the system is expected to adapt easily to CLIC even if it means to control modules that involve up to a maximum of 384 motors and 896 sensors

Segmented trapped vortex cavity

Science.gov (United States)

Grammel, Jr., Leonard Paul (Inventor); Pennekamp, David Lance (Inventor); Winslow, Jr., Ralph Henry (Inventor)

2010-01-01

An annular trapped vortex cavity assembly segment comprising includes a cavity forward wall, a cavity aft wall, and a cavity radially outer wall there between defining a cavity segment therein. A cavity opening extends between the forward and aft walls at a radially inner end of the assembly segment. Radially spaced apart pluralities of air injection first and second holes extend through the forward and aft walls respectively. The segment may include first and second expansion joint features at distal first and second ends respectively of the segment. The segment may include a forward subcomponent including the cavity forward wall attached to an aft subcomponent including the cavity aft wall. The forward and aft subcomponents include forward and aft portions of the cavity radially outer wall respectively. A ring of the segments may be circumferentially disposed about an axis to form an annular segmented vortex cavity assembly.

A Compact Microwave Microfluidic Sensor Using a Re-Entrant Cavity

Directory of Open Access Journals (Sweden)

Hayder Hamzah

2018-03-01

Full Text Available A miniaturized 2.4 GHz re-entrant cavity has been designed, manufactured and tested as a sensor for microfluidic compositional analysis. It has been fully evaluated experimentally with water and common solvents, namely methanol, ethanol, and chloroform, with excellent agreement with the expected behaviour predicted by the Debye model. The sensor’s performance has also been assessed for analysis of segmented flow using water and oil. The samples’ interaction with the electric field in the gap region has been maximized by aligning the sample tube parallel to the electric field in this region, and the small width of the gap (typically 1 mm result in a highly localised complex permittivity measurement. The re-entrant cavity has simple mechanical geometry, small size, high quality factor, and due to the high concentration of electric field in the gap region, a very small mode volume. These factors combine to result in a highly sensitive, compact sensor for both pure liquids and liquid mixtures in capillary or microfluidic environments.

PET imaging of 64Cu-DOTA-scFv-anti-PSMA lipid nanoparticles (LNPs): Enhanced tumor targeting over anti-PSMA scFv or untargeted LNPs

International Nuclear Information System (INIS)

Wong, Patty; Li, Lin; Chea, Junie; Delgado, Melissa K.; Crow, Desiree; Poku, Erasmus; Szpikowska, Barbara; Bowles, Nicole; Channappa, Divya; Colcher, David; Wong, Jeffrey Y.C.; Shively, John E.; Yazaki, Paul J.

2017-01-01

Introduction: Single chain (scFv) antibodies are ideal targeting ligands due to their modular structure, high antigen specificity and affinity. These monovalent ligands display rapid tumor targeting but have limitations due to their fast urinary clearance. Methods: An anti-prostate membrane antigen (PSMA) scFv with a site-specific cysteine was expressed and evaluated in a prostate cancer xenograft model by Cu-64 PET imaging. To enhance tumor accumulation, the scFv-cys was conjugated to the co-polymer DSPE-PEG-maleimide that spontaneously assembled into a homogeneous multivalent lipid nanoparticle (LNP). Results: The targeted LNP exhibited a 2-fold increase in tumor uptake compared to the scFv alone using two different thiol ester chemistries. The anti-PSMA scFv-LNP exhibited a 1.6 fold increase in tumor targeting over the untargeted LNP. Conclusions: The targeted anti-PSMA scFv-LNP showed enhanced tumor accumulation over the scFv alone or the untargeted DOTA-micelle providing evidence for the development of this system for drug delivery. Advances in knowledge and implications for patient care: Anti-tumor scFv antibody fragments have not achieved their therapeutic potential due to their fast blood clearance. Conjugation to an LNP enables multivalency to the tumor antigen as well as increased molecular size for chemotherapy drug delivery.

A Further Study of the Products of Sc and Dioxygen Reactions

Science.gov (United States)

Bauschlicher, Charles W., Jr.; Zhou, Mingfei; Andrews, Lester; Johnson, J. R. Tobias; Panas, Itai; Snis, Anders; Roos, Bjoern O.; Arnold, James O. (Technical Monitor)

1999-01-01

The products of the reaction of Sc and dioxygen have been reinvestigated. By adding the electron-trapping molecule CC14, additional information about the IR spectra has been obtained, as well as the observation of new bands. New ab initio calculations are also performed on possible products of the Sc plus O2 reaction. The previously observed band at 722.5 per cm is assigned as the b2 mode of ScO2(-). Bands arising from ScO(+), Sc(O2)(+), and(O2)ScO are also assigned. We are still unable to assign any bands to OScO. The problems associated with the computational study of ScO2 are discussed.

Synthesis and Isolation of the Titanium-Scandium Endohedral Fullerenes-Sc2 TiC@Ih -C80 , Sc2 TiC@D5h -C80 and Sc2 TiC2 @Ih -C80 : Metal Size Tuning of the Ti(IV) /Ti(III) Redox Potentials.

Science.gov (United States)

Junghans, Katrin; Ghiassi, Kamran B; Samoylova, Nataliya A; Deng, Qingming; Rosenkranz, Marco; Olmstead, Marilyn M; Balch, Alan L; Popov, Alexey A

2016-09-05

The formation of endohedral metallofullerenes (EMFs) in an electric arc is reported for the mixed-metal Sc-Ti system utilizing methane as a reactive gas. Comparison of these results with those from the Sc/CH4 and Ti/CH4 systems as well as syntheses without methane revealed a strong mutual influence of all key components on the product distribution. Whereas a methane atmosphere alone suppresses the formation of empty cage fullerenes, the Ti/CH4 system forms mainly empty cage fullerenes. In contrast, the main fullerene products in the Sc/CH4 system are Sc4 C2 @C80 (the most abundant EMF from this synthesis), Sc3 C2 @C80 , isomers of Sc2 C2 @C82 , and the family Sc2 C2 n (2 n=74, 76, 82, 86, 90, etc.), as well as Sc3 CH@C80 . The Sc-Ti/CH4 system produces the mixed-metal Sc2 TiC@C2 n (2 n=68, 78, 80) and Sc2 TiC2 @C2 n (2 n=80) clusterfullerene families. The molecular structures of the new, transition-metal-containing endohedral fullerenes, Sc2 TiC@Ih -C80 , Sc2 TiC@D5h -C80 , and Sc2 TiC2 @Ih -C80 , were characterized by NMR spectroscopy. The structure of Sc2 TiC@Ih -C80 was also determined by single-crystal X-ray diffraction, which demonstrated the presence of a short Ti=C double bond. Both Sc2 TiC- and Sc2 TiC2 -containing clusterfullerenes have Ti-localized LUMOs. Encapsulation of the redox-active Ti ion inside the fullerene cage enables analysis of the cluster-cage strain in the endohedral fullerenes through electrochemical measurements. © 2016 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.

Implosion of the small cavity and large cavity cannonball targets

International Nuclear Information System (INIS)

Nishihara, Katsunobu; Yamanaka, Chiyoe.

1984-01-01

Recent results of cannonball target implosion research are briefly reviewed with theoretical predictions for GEKKO XII experiments. The cannonball targets are classified into two types according to the cavity size ; small cavity and large cavity. The compression mechanisms of the two types are discussed. (author)

Efficient Characterization of Protein Cavities within Molecular Simulation Trajectories: trj_cavity.

Science.gov (United States)

Paramo, Teresa; East, Alexandra; Garzón, Diana; Ulmschneider, Martin B; Bond, Peter J

2014-05-13

Protein cavities and tunnels are critical in determining phenomena such as ligand binding, molecular transport, and enzyme catalysis. Molecular dynamics (MD) simulations enable the exploration of the flexibility and conformational plasticity of protein cavities, extending the information available from static experimental structures relevant to, for example, drug design. Here, we present a new tool (trj_cavity) implemented within the GROMACS ( www.gromacs.org ) framework for the rapid identification and characterization of cavities detected within MD trajectories. trj_cavity is optimized for usability and computational efficiency and is applicable to the time-dependent analysis of any cavity topology, and optional specialized descriptors can be used to characterize, for example, protein channels. Its novel grid-based algorithm performs an efficient neighbor search whose calculation time is linear with system size, and a comparison of performance with other widely used cavity analysis programs reveals an orders-of-magnitude improvement in the computational cost. To demonstrate its potential for revealing novel mechanistic insights, trj_cavity has been used to analyze long-time scale simulation trajectories for three diverse protein cavity systems. This has helped to reveal, respectively, the lipid binding mechanism in the deep hydrophobic cavity of a soluble mite-allergen protein, Der p 2; a means for shuttling carbohydrates between the surface-exposed substrate-binding and catalytic pockets of a multidomain, membrane-proximal pullulanase, PulA; and the structural basis for selectivity in the transmembrane pore of a voltage-gated sodium channel (NavMs), embedded within a lipid bilayer environment. trj_cavity is available for download under an open-source license ( http://sourceforge.net/projects/trjcavity ). A simplified, GROMACS-independent version may also be compiled.

Energy Levels, wavelengths and hyperfine structure measurements of Sc II

Science.gov (United States)

Hala, Fnu; Nave, Gillian

2018-01-01

Lines of singly ionized Scandium (Sc II) along with other Iron group elements have been observed [1] in the region surrounding the massive star Eta Carinae [2,3] called the strontium filament (SrF). The last extensive analysis of Sc II was the four-decade old work of Johansson & Litzen [4], using low-resolution grating spectroscopy. To update and extend the Sc II spectra, we have made observation of Sc/Ar, Sc/Ne and Sc/Ge/Ar hollow cathode emission spectrum on the NIST high resolution FT700 UV/Vis and 2 m UV/Vis/IR Fourier transform spectrometers (FTS). More than 850 Sc II lines have been measured in the wavelength range of 187 nm to 3.2 μm. connecting a total of 152 energy levels. The present work also focuses to resolve hyperfine structure (HFS) in Sc II lines. We aim to obtain accurate transition wavelengths, improved energy levels and HFS constants of Sc II. The latest results from work in progress will be presented.Reference[1] Hartman H, Gull T, Johansson S and Smith N 2004 Astron. Astrophys. 419 215[2] Smith N, Morse J A and Gull T R 2004 Astrophys. J. 605 405[3] Davidson K and Humphreys R M 1997 Annu. Rev. Astron. Astrophys. 35[4] Johansson S and Litzén U 1980 Phys. Scr. 22 49

Sc-Decorated WS_2 Nanoribbons as Hydrogen Storage Media

International Nuclear Information System (INIS)

Xu Bin; Wang Yu-Sheng; Zhang Jing; Song Na-Hong; Li Meng; Yi Lin

2016-01-01

The hydrogen storage behavior of Sc-decorated WS_2 monolayer and WS_2 nanoribbons is systematically studied by using first principles calculations based on the density functional theory. The present results indicate that an Sc-decorated WS_2 monolayer is not suitable for storing hydrogen due to the weak interaction between the monolayer WS_2 sheet and the Sc atoms. It is found that both the hybridization mechanism and the Coulomb attraction make the Sc atoms stably adsorb on the edges of WS_2 nanoribbons without clustering. The 2Sc/WS_2 NRs system can adsorb at most eight H_2 molecules with average adsorption energy of 0.20 eV/H_2. The results show that the desorption of H_2 is possible by lowering the pressure or by increasing the temperature. (paper)

CORRELATION BETWEEN SEED TESTS AND FIELD EMERGENCE OF TWO MAIZE HYBRIDS (SC704 AND SC500)

OpenAIRE

A.A. ALILOO; B. SHOKATI

2011-01-01

Early emergence and stand establishment of maize (Zea mays L.) are considered to be the most important yield-contributing factors. The influence of seed vigor on these factors is vital. Therefore, five laboratory tests and field experiment were conducted on basis of a randomized complete block design (RCBD) with five replications in 2011, to evaluate the correlation among the seed vigor tests and field emergence of two maize hybrids (SC704 and SC500). In laboratory tests, differences between ...

Depletion of Arabidopsis SC35 and SC35-like serine/arginine-rich proteins affects the transcription and splicing of a subset of genes.

Science.gov (United States)

Yan, Qingqing; Xia, Xi; Sun, Zhenfei; Fang, Yuda

2017-03-01

Serine/arginine-rich (SR) proteins are important splicing factors which play significant roles in spliceosome assembly and splicing regulation. However, little is known regarding their biological functions in plants. Here, we analyzed the phenotypes of mutants upon depleting different subfamilies of Arabidopsis SR proteins. We found that loss of the functions of SC35 and SC35-like (SCL) proteins cause pleiotropic changes in plant morphology and development, including serrated leaves, late flowering, shorter roots and abnormal silique phyllotaxy. Using RNA-seq, we found that SC35 and SCL proteins play roles in the pre-mRNA splicing. Motif analysis revealed that SC35 and SCL proteins preferentially bind to a specific RNA sequence containing the AGAAGA motif. In addition, the transcriptions of a subset of genes are affected by the deletion of SC35 and SCL proteins which interact with NRPB4, a specific subunit of RNA polymerase II. The splicing of FLOWERING LOCUS C (FLC) intron1 and transcription of FLC were significantly regulated by SC35 and SCL proteins to control Arabidopsis flowering. Therefore, our findings provide mechanistic insight into the functions of plant SC35 and SCL proteins in the regulation of splicing and transcription in a direct or indirect manner to maintain the proper expression of genes and development.

Superconducting accelerating structures for very low velocity ion beams

Directory of Open Access Journals (Sweden)

J. Xu

2008-03-01

Full Text Available This paper presents designs for four types of very-low-velocity superconducting (SC accelerating cavity capable of providing several MV of accelerating potential per cavity, and suitable for particle velocities in the range 0.006cavities have been widely applied to cw acceleration of ion beams. SC linacs can be formed as an array of independently phased cavities, enabling a variable velocity profile to maximize the output energy for each of a number of different ion species. Several laboratories in the U.S. and Europe are planning exotic beam facilities based on SC linacs. The cavity designs presented here are intended for the front end of such linacs, particularly for the postacceleration of rare isotopes of low charge state. Several types of SC cavities have been developed recently to cover particle velocities above 0.06c. Superconducting four-gap quarter-wave resonators for velocities 0.008<β=v/c<0.05 were developed about two decades ago and have been successfully operated at the ATLAS SC linac at Argonne National Laboratory. Since that time, progress in simulation tools, cavity fabrication, and processing have increased SC cavity gradients by a factor of 3–4. This paper applies these tools to optimize the design of a four-gap quarter-wave resonator for exotic beam facilities and other low-velocity applications.

DiSC-OPAL

DEFF Research Database (Denmark)

Kemal, Mohammed Seifu; Pedersen, Rasmus; Iov, Florin

2017-01-01

of such systems. The simulation tool should be able to model Electrical Grid and flexible assets with different time scales and resolution levels fulfilling specific functionalities. In this paper DiSC-OPAL, an OPAL-RT compatible toolbox library for modelling of assets is presented. The library is suitable...

New indides Sc{sub 6}Co{sub 2.18}In{sub 0.82}, Sc{sub 10}Ni{sub 9}In{sub 19.44} and ScCu{sub 4}In-synthesis, structure, and crystal chemistry

Energy Technology Data Exchange (ETDEWEB)

Zaremba, R.I.; Rodewald, U. Ch.; Poettgen, R. [Inst. fuer Anorganische und Analytische Chemie, Westfaelische Wilhelms-Univ. Muenster (Germany); Kalychak, Y.M.; Zaremba, V.I. [Inorganic Chemistry Dept., Ivan Franko National Univ. of Lviv, Lviv (Ukraine)

2006-08-15

New indides Sc{sub 6}Co{sub 2.18}In{sub 0.82}, Sc{sub 10}Ni{sub 9}In{sub 19.44} and ScCu{sub 4}In have been synthesized from the elements by arc-melting. Single crystals were grown by special annealing modes. The thee indides were investigated via X-ray powder and single crystal diffraction: Ho{sub 6}Co{sub 2}Ga type, Immm, a = 886.7(3), b = 878.0(2), c = 932.1(3) pm, wR2 = 0.0517, 711 F{sup 2} values, 35 variables for Sc{sub 6}Co{sub 2.18}In{sub 0.82}, Ho{sub 10}Ni{sub 9}In{sub 20} type, P4/nmm, a = 1287.5(2), c = 884.7(1) pm, wR2 = 0.0642, 1221 F{sup 2} values, 63 variables for Sc{sub 10}Ni{sub 9}In{sub 19.44}, and MgCu{sub 4}Sn type, anti F 43m, a = 704.03(7) pm, wR2 = 0.0267, 101 F{sup 2} values, and 7 variables for ScCu{sub 4}In. The scandium rich indide Sc{sub 6}Co{sub 2.18}In{sub 0.82} contains two Co{sub 2} dumb-bells at Co-Co distances of 221 and 230 pm. Each cobalt atom within these dumb-bells has a tricapped trigonal prismatic coordination. The In1 site has a distorted cube-like coordination by scandium and shows a mixed occupancy (36%) with cobalt. The In2 atoms have distorted icosahedral scandium coordination. As a consequence of the small size of the scandium atoms, the In4 site in Sc{sub 10}Ni{sub 9}In{sub 19.44} shows defects and was furthermore refined with a split model leading to a new distorted variant within the family of Ho{sub 10}Ni{sub 9}In{sub 20} compounds. ScCu{sub 4}In is an ordered version of the cubic Laves phase with scandium and indium atoms in the CN16 voids of the copper substructure. The Cu-Cu distances within the three-dimensional network of corner-sharing tetrahedra are 248.6 and 249.2 pm. The crystal chemical peculiarities of these three indide structures are briefly discussed. (orig.)

PET Imaging of 64Cu-DOTA-scFv-Anti-PSMA Lipid Nanoparticles (LNPs): Enhanced Tumor Targeting over Anti-PSMA scFv or Untargeted LNPs

Science.gov (United States)

Wong, Patty; Li, Lin; Chea, Junie; Delgado, Melissa K.; Crow, Desiree; Poku, Erasmus; Szpikowska, Barbara; Bowles, Nicole; Channappa, Divya; Colcher, David; Wong, Jeffrey Y.C.; Shively, John E.; Yazaki, Paul J.

2017-01-01

Introduction Single chain (scFv) antibodies are ideal targeting ligands due to their modular structure, high antigen specificity and affinity. These monovalent ligands display rapid tumor targeting but have limitations due to their fast urinary clearance. Methods An anti-prostate membrane antigen (PSMA) scFv with a site-specific cysteine was expressed and evaluated in a prostate cancer xenograft model by Cu-64 PET imaging. To enhance tumor accumulation, the scFv-cys was conjugated to the co-polymer DSPE-PEG-maleimide that spontaneously assembled into a homogeneous multivalent lipid nanoparticle (LNP). Results The targeted LNP exhibited a 2-fold increase in tumor uptake compared to the scFv alone using two different thiol ester chemistries. The anti-PSMA scFv-LNP exhibited a 1.6 fold increase in tumor targeting over the untargeted LNP. Conclusions The targeted anti-PSMA scFv-LNP showed enhanced tumor accumulation over the scFv alone or the untargeted DOTA-micelle providing evidence for the development of this system for drug delivery. Advances in Knowledge and implications for patient care Anti-tumor scFv antibody fragments have not achieved their therapeutic potential due to their fast blood clearance. Conjugation to a LNP enables multivalency to the tumor antigen as well as increased molecular size for chemotherapy drug delivery. PMID:28126683

Molecular and functional characterization of peptidoglycan-recognition protein SC2 (PGRP-SC2) from Nile tilapia (Oreochromis niloticus) involved in the immune response to Streptococcus agalactiae.

Science.gov (United States)

Gan, Zhen; Chen, Shannan; Hou, Jing; Huo, Huijun; Zhang, Xiaolin; Ruan, Baiye; Laghari, Zubair Ahmed; Li, Li; Lu, Yishan; Nie, Pin

2016-07-01

PGRP-SC2, the member of PGRP family, plays an important role in regulation of innate immune response. In this paper, a PGRP-SC2 gene of Nile tilapia, Oreochromis niloticus (designated as On-PGRP-SC2) was cloned and its expression pattern under the infection of Streptococcus agalactiae was investigated. Sequence analysis showed main structural features required for amidase activity were detected in the deduced amino acid sequence of On-PGRP-SC2. In healthy tilapia, the On-PGRP-SC2 transcripts could be detected in all the examined tissues, with the most abundant expression in the muscle. When infected with S. agalactiae, there was a clear time-dependent expression pattern of On-PGRP-SC2 in the spleen, head kidney and brain. The assays for the amidase activity suggested that recombinant On-PGRP-SC2 protein had a Zn(2+)-dependent PGN-degrading activity. Moreover, our works showed that recombinant On-PGRP-SC2 protein could significantly reduce bacterial load in target organs attacked by S. agalactiae. These findings indicated that On-PGRP-SC2 may play important roles in the immune response to S. agalactiae in Nile tilapia. Copyright © 2016 Elsevier Ltd. All rights reserved.

Red-cockaded woodpecker nest-cavity selection: relationships with cavity age and resin production

Science.gov (United States)

Richard N. Conner; Daniel Saenz; D. Craig Rudolph; William G. Ross; David L. Kulhavy

1998-01-01

The authors evaluated selection of nest sites by male red-cockaded woodpeckers (Picoides borealis) in Texas relative to the age of the cavity when only cavities excavated by the woodpeckers were available and when both naturally excavated cavities and artificial cavities were available. They also evaluated nest-cavity selection relative to the ability of naturally...

Development of SC structure modularization in Nuclear Power Plant

International Nuclear Information System (INIS)

Mun, Taeyoup

2008-01-01

New Focus on NPP are Rising Concerns on Global Warming, Potential energy crisis (geo-political), Improved reliability and safety of nuclear power plant, Advent of Generation 3+ NPP technology and Economical Energy Resource. New NPPs are 6 units in Korea and 23 in Asia being built, 32 units being planned in China by 2020 (150 by 2050), 10 units being planned in US by 2020 and IAEA expects $200 billions on NPP construction next 25 years (up to 30% of total world energy). □ SC(Steel Plate Concrete) structure · Steel Plate is used as a Structural Element instead of Reinforcing Bars in RC · SC structure consists of Steel Plate with Headed Studs. Connected by Tie-bars - The Primary Purpose of Tie-bars is to Stiffen and Hold Together the Plates during Construction Process - Headed Studs are Welded to the Inside of Steel Plate for composite action □ Benefits of SC Structure · Shorten Construction Duration for Re bar, Forming and Scaffolding Works · Minimize Site Labors · Improve the Construction Quality · Enable Construction Sites to be kept Clean □ SC Modularization · Fit for Modular Construction for Structural Features · Fit for Modular Construction for Structural Features · Inattentively Effective for Integrated Modules · Pre-fabrication, Pre-assembly and Modularization □ Project Overview · Project Name: Development of SC structure for Modularization in NPP · Project Type: Electric Power Industry R and D (Ministry of Knowledge Economy) · Duration: Sep. 2005 ∼ Aug. 2008 (36 Months) · Research Team and Scopes - Project Management: Korea Hydro and Nuclear Power Company (KHNP) - Development of Code and Standards for SC Structure: Korea Society of Steel Construction (KSSC) Korea Electric Power Research Institute (KEPRI) - Development of SC Structural Analysis and Design: Korea Power Engineering Company (KOPEC) - Development of Construction Techniques for SC Modularization: KHNP, Korea Institute of Nuclear Safety(KINS), KOPEC □ Performance

Dental cavities

Science.gov (United States)

... this page: //medlineplus.gov/ency/article/001055.htm Dental cavities To use the sharing features on this page, please enable JavaScript. Dental cavities are holes (or structural damage) in the ...

Pascal-SC a computer language for scientific computation

CERN Document Server

Bohlender, Gerd; von Gudenberg, Jürgen Wolff; Rheinboldt, Werner; Siewiorek, Daniel

1987-01-01

Perspectives in Computing, Vol. 17: Pascal-SC: A Computer Language for Scientific Computation focuses on the application of Pascal-SC, a programming language developed as an extension of standard Pascal, in scientific computation. The publication first elaborates on the introduction to Pascal-SC, a review of standard Pascal, and real floating-point arithmetic. Discussions focus on optimal scalar product, standard functions, real expressions, program structure, simple extensions, real floating-point arithmetic, vector and matrix arithmetic, and dynamic arrays. The text then examines functions a

Thermodynamic modeling of the Sc-Zn system coupled with first-principles calculation

Directory of Open Access Journals (Sweden)

Tang C.

2012-01-01

Full Text Available The Sc-Zn system has been critically reviewed and assessed by means of CALPHAD (CALculation of PHAse Diagram approach. By means of first-principles calculation, the enthalpies of formation at 0 K for the ScZn, ScZn2, Sc17Zn58, Sc3Zn17 and ScZn12 have been computed with the desire to assist thermodynamic modeling. A set of self-consistent thermodynamic parameters for the Sc-Zn system is then obtained. The calculated phase diagram and thermodynamic properties agree well with the experimental data and first-principles calculations, respectively.

Superconducting TESLA cavities

Directory of Open Access Journals (Sweden)

B. Aune

2000-09-01

Full Text Available The conceptional design of the proposed linear electron-positron collider TESLA is based on 9-cell 1.3 GHz superconducting niobium cavities with an accelerating gradient of E_{acc}≥25 MV/m at a quality factor Q_{0}≥5×10^{9}. The design goal for the cavities of the TESLA Test Facility (TTF linac was set to the more moderate value of E_{acc}≥15 MV/m. In a first series of 27 industrially produced TTF cavities the average gradient at Q_{0}=5×10^{9} was measured to be 20.1±6.2 MV/m, excluding a few cavities suffering from serious fabrication or material defects. In the second production of 24 TTF cavities, additional quality control measures were introduced, in particular, an eddy-current scan to eliminate niobium sheets with foreign material inclusions and stringent prescriptions for carrying out the electron-beam welds. The average gradient of these cavities at Q_{0}=5×10^{9} amounts to 25.0±3.2 MV/m with the exception of one cavity suffering from a weld defect. Hence only a moderate improvement in production and preparation techniques will be needed to meet the ambitious TESLA goal with an adequate safety margin. In this paper we present a detailed description of the design, fabrication, and preparation of the TESLA Test Facility cavities and their associated components and report on cavity performance in test cryostats and with electron beam in the TTF linac. The ongoing research and development towards higher gradients is briefly addressed.

AlignMe—a membrane protein sequence alignment web server

Science.gov (United States)

Stamm, Marcus; Staritzbichler, René; Khafizov, Kamil; Forrest, Lucy R.

2014-01-01

We present a web server for pair-wise alignment of membrane protein sequences, using the program AlignMe. The server makes available two operational modes of AlignMe: (i) sequence to sequence alignment, taking two sequences in fasta format as input, combining information about each sequence from multiple sources and producing a pair-wise alignment (PW mode); and (ii) alignment of two multiple sequence alignments to create family-averaged hydropathy profile alignments (HP mode). For the PW sequence alignment mode, four different optimized parameter sets are provided, each suited to pairs of sequences with a specific similarity level. These settings utilize different types of inputs: (position-specific) substitution matrices, secondary structure predictions and transmembrane propensities from transmembrane predictions or hydrophobicity scales. In the second (HP) mode, each input multiple sequence alignment is converted into a hydrophobicity profile averaged over the provided set of sequence homologs; the two profiles are then aligned. The HP mode enables qualitative comparison of transmembrane topologies (and therefore potentially of 3D folds) of two membrane proteins, which can be useful if the proteins have low sequence similarity. In summary, the AlignMe web server provides user-friendly access to a set of tools for analysis and comparison of membrane protein sequences. Access is available at http://www.bioinfo.mpg.de/AlignMe PMID:24753425

Using the etalon effect for in situ balancing of the Advanced Virgo arm cavities

International Nuclear Information System (INIS)

Hild, S; Freise, A; Chelkowski, S; Mantovani, M; Degallaix, J; Schilling, R

2009-01-01

Several large-scale interferometric gravitational-wave detectors use resonant arm cavities to enhance the light power in the interferometer arms. These cavities are based on different optical designs: One design uses wedged input mirrors to create additional optical pick-off ports for deriving control signals. The second design employs input mirrors without wedge and thus offers the possibility of using the etalon effect inside the input mirrors for tuning the finesse of the arm cavities. In this paper, we introduce a concept of maximum flexibility that combines both of these options, by featuring wedges at the input mirrors and using the etalon effect instead in the end mirrors. We present a design for the arm cavities of Advanced Virgo. The paper focusses on evaluating the influence of etalon imperfections onto the overall Advanced Virgo performance. We use numerical simulations to derive requirements for the manufacturing accuracy of an end mirror etalon for Advanced Virgo. Furthermore, we give analytical approximations for the achievable tuning range of an imperfect etalon depending on the curvature and orientation mismatch of the two etalon surfaces. We evaluate the displacement noise originating from temperature driven optical phase noise of the etalon. In addition the influence of the etalon effect onto other Advanced Virgo subsystems such as the alignment sensing and control is analysed.

X-ray quantum optics with Moessbauer nuclei in thin-film cavities

Energy Technology Data Exchange (ETDEWEB)

Heeg, Kilian Peter

2014-12-09

In this thesis thin-film cavities with embedded Moessbauer nuclei probed by near-resonant X-ray light are studied from a quantum optical perspective. A theoretical framework is developed and compact expressions for the observables are derived for the linear excitation regime, which is encountered in current experiments. Even advanced cavity layouts can be modeled in excellent agreement with the results of previous experiments and semi-classical approaches. In the absence of magnetic hyperfine splitting, the spectral response of the system is found to be formed by tunable Fano profiles. An experimental implementation of this line shape control allows to extract spectroscopic signatures with high precision and to reconstruct the phase of the nuclear transition in good agreement with the theoretical predictions. The alignment of medium magnetization and polarization control of the X-rays enable to engineer advanced quantum optical level schemes, in which vacuum induced coherence effects are predicted and successfully demonstrated in an experiment. Furthermore, it is shown that group velocity control for x-ray pulses can be achieved in the cavity. A scheme for its observation is proposed and then employed to experimentally confirm sub-luminal X-ray propagation. Finally, non-linear effects, which could become accessible with future light sources, are explored and a non-linear line shape control mechanism is discussed.

Lifetime and g-factor measurements in 44Sc

International Nuclear Information System (INIS)

Chevallier, A.; Chavallier, J.; Gross, J.L.; Haas, B.; Schulz, N.; Styczen, J.; Toulemonde, M.

1975-01-01

The lifetimes of the 235 keV, 2 - state and 350 keV, 4 + state in 44 Sc have been measured via the 44 Ca(p, n) 44 Sc reaction with a pulsed proton beam. The time integral perturbed angular distribution technique with an external field was used to measure the precession angles of the 2 - and 4 + states populated by the 30 Si( 16 O, pnγ) 44 Sc reaction. The following values for the mean-lives and g-factors were obtained: π(2 - ) = 8.83(33) ns, g(2 - ) = 0.30(13) and π(4 + ) = 4.52(27)ns, g(4 + ) = 0.90(12). The results for the 2 - state support a rotational description of the negative parity states in 44 Sc. The magnetic moment of the 4 + state is compared to shell model predictions. (orig.) [de

Linear beam dynamics and ampere class superconducting RF cavities at RHIC

Science.gov (United States)

Calaga, Rama R.

The Relativistic Heavy Ion Collider (RHIC) is a hadron collider designed to collide a range of ions from protons to gold. RHIC operations began in 2000 and has successfully completed five physics runs with several species including gold, deuteron, copper, and polarized protons. Linear optics and coupling are fundamental issues affecting the collider performance. Measurement and correction of optics and coupling are important to maximize the luminosity and sustain stable operation. A numerical approach, first developed at SLAC, was implemented to measure linear optics from coherent betatron oscillations generated by ac dipoles and recorded at multiple beam position monitors (BPMs) distributed around the collider. The approach is extended to a fully coupled 2D case and equivalence relationships between Hamiltonian and matrix formalisms are derived. Detailed measurements of the transverse coupling terms are carried out at RHIC and correction strategies are applied to compensate coupling both locally and globally. A statistical approach to determine BPM reliability and performance over the past three runs and future improvements also discussed. Aiming at a ten-fold increase in the average heavy-ion luminosity, electron cooling is the enabling technology for the next luminosity upgrade (RHIC II). Cooling gold ion beams at 100 GeV/nucleon requires an electron beam of approximately 54 MeV and a high average current in the range of 50-200 mA. All existing e-Coolers are based on low energy DC accelerators. The only viable option to generate high current, high energy, low emittance CW electron beam is through a superconducting energy-recovery linac (SC-ERL). In this option, an electron beam from a superconducting injector gun is accelerated using a high gradient (˜ 20 MV/m) superconducting RF (SRF) cavity. The electrons are returned back to the cavity with a 180° phase shift to recover the energy back into the cavity before being dumped. A design and development of a half

Electronic structure and local distortions in epitaxial ScGaN films

International Nuclear Information System (INIS)

Knoll, S M; Zhang, S; Rovezzi, M; Joyce, T B; Moram, M A

2014-01-01

High energy resolution fluorescence-detected x-ray absorption spectroscopy and density functional theory calculations were used to investigate the local bonding and electronic structure of Sc in epitaxial wurtzite-structure Sc x Ga 1−x N films with x ≤ 0.059. Sc atoms are found to substitute for Ga atoms, accompanied by a local distortion involving an increase in the internal lattice parameter u around the Sc atoms. The local bonding and electronic structure at Sc are not affected strongly by the strain state or the defect microstructure of the films. These data are consistent with theoretical predictions regarding the electronic structure of dilute Sc x Ga 1−x N alloys. (paper)

GraphAlignment: Bayesian pairwise alignment of biological networks

Directory of Open Access Journals (Sweden)

Kolář Michal

2012-11-01

Full Text Available Abstract Background With increased experimental availability and accuracy of bio-molecular networks, tools for their comparative and evolutionary analysis are needed. A key component for such studies is the alignment of networks. Results We introduce the Bioconductor package GraphAlignment for pairwise alignment of bio-molecular networks. The alignment incorporates information both from network vertices and network edges and is based on an explicit evolutionary model, allowing inference of all scoring parameters directly from empirical data. We compare the performance of our algorithm to an alternative algorithm, Græmlin 2.0. On simulated data, GraphAlignment outperforms Græmlin 2.0 in several benchmarks except for computational complexity. When there is little or no noise in the data, GraphAlignment is slower than Græmlin 2.0. It is faster than Græmlin 2.0 when processing noisy data containing spurious vertex associations. Its typical case complexity grows approximately as O(N2.6. On empirical bacterial protein-protein interaction networks (PIN and gene co-expression networks, GraphAlignment outperforms Græmlin 2.0 with respect to coverage and specificity, albeit by a small margin. On large eukaryotic PIN, Græmlin 2.0 outperforms GraphAlignment. Conclusions The GraphAlignment algorithm is robust to spurious vertex associations, correctly resolves paralogs, and shows very good performance in identification of homologous vertices defined by high vertex and/or interaction similarity. The simplicity and generality of GraphAlignment edge scoring makes the algorithm an appropriate choice for global alignment of networks.

Cavity quantum electrodynamics

International Nuclear Information System (INIS)

Walther, Herbert; Varcoe, Benjamin T H; Englert, Berthold-Georg; Becker, Thomas

2006-01-01

This paper reviews the work on cavity quantum electrodynamics of free atoms. In recent years, cavity experiments have also been conducted on a variety of solid-state systems resulting in many interesting applications, of which microlasers, photon bandgap structures and quantum dot structures in cavities are outstanding examples. Although these phenomena and systems are very interesting, discussion is limited here to free atoms and mostly single atoms because these systems exhibit clean quantum phenomena and are not disturbed by a variety of other effects. At the centre of our review is the work on the one-atom maser, but we also give a survey of the entire field, using free atoms in order to show the large variety of problems dealt with. The cavity interaction can be separated into two main regimes: the weak coupling in cavity or cavity-like structures with low quality factors Q and the strong coupling when high-Q cavities are involved. The weak coupling leads to modification of spontaneous transitions and level shifts, whereas the strong coupling enables one to observe a periodic exchange of photons between atoms and the radiation field. In this case, atoms and photons are entangled, this being the basis for a variety of phenomena observed, some of them leading to interesting applications in quantum information processing. The cavity experiments with free atoms reached a new domain with the advent of experiments in the visible spectral region. A review on recent achievements in this area is also given

Effects of hydroxyurea treatment for patients with hemoglobin SC disease.

Science.gov (United States)

Luchtman-Jones, Lori; Pressel, Sara; Hilliard, Lee; Brown, R Clark; Smith, Mary G; Thompson, Alexis A; Lee, Margaret T; Rothman, Jennifer; Rogers, Zora R; Owen, William; Imran, Hamayun; Thornburg, Courtney; Kwiatkowski, Janet L; Aygun, Banu; Nelson, Stephen; Roberts, Carla; Gauger, Cynthia; Piccone, Connie; Kalfa, Theodosia; Alvarez, Ofelia; Hassell, Kathryn; Davis, Barry R; Ware, Russell E

2016-02-01

Although hemoglobin SC (HbSC) disease is usually considered less severe than sickle cell anemia (SCA), which includes HbSS and HbS/β(0) -thalassemia genotypes, many patients with HbSC experience severe disease complications, including vaso-occlusive pain, acute chest syndrome, avascular necrosis, retinopathy, and poor quality of life. Fully 20 years after the clinical and laboratory efficacy of hydroxyurea was proven in adult SCA patients, the safety and utility of hydroxyurea treatment for HbSC patients remain unclear. Recent NHLBI evidence-based guidelines highlight this as a critical knowledge gap, noting HbSC accounts for ∼30% of sickle cell patients within the United States. To date, only 5 publications have reported short-term, incomplete, or conflicting laboratory and clinical outcomes of hydroxyurea treatment in a total of 71 adults and children with HbSC. We now report on a cohort of 133 adult and pediatric HbSC patients who received hydroxyurea, typically for recurrent vaso-occlusive pain. Hydroxyurea treatment was associated with a stable hemoglobin concentration; increased fetal hemoglobin (HbF) and mean corpuscular volume (MCV); and reduced white blood cell count (WBC), absolute neutrophil count (ANC), and absolute reticulocyte count (ARC). Reversible cytopenias occurred in 22% of patients, primarily neutropenia and thrombocytopenia. Painful events were reduced with hydroxyurea, more in patients >15 years old. These multicenter data support the safety and potentially salutary effects of hydroxyurea treatment for HbSC disease; however, a multicenter, placebo-controlled, Phase 3 clinical trial is needed to determine if hydroxyurea therapy has efficacy for patients with HbSC disease. © 2015 Wiley Periodicals, Inc.

Design of SC walls and slabs for impulsive loading

Energy Technology Data Exchange (ETDEWEB)

Varma, Amit H. [Purdue Univ., West Lafayette, IN (United States)

2015-11-11

Reinforced concrete (RC) structures have historically been the preferred choice for blast resistant structures because of their mass and the ductility provided by steel reinforcement. Steel-plate composite (SC) walls are a viable alternative to RC for protecting the infrastructure against explosive threats. SC structures consist of two steel faceplates with a plain concrete core between them. The steel faceplates are anchored to the concrete using stud anchors and connected to each other using tie bars. SC structures provide mass from the concrete infill and ductility from the continuous external steel faceplates. This dissertation presents findings and recommendations from experimental and analytical investigations of the performance of SC walls subjected to far-field blast loads.

LOCAL COLLISION SIMULATION OF AN SC WALL USING ENERGY ABSORBING STEEL

Directory of Open Access Journals (Sweden)

CHUL-HUN CHUNG

2013-08-01

Full Text Available This study evaluates the local damage of a turbine in an auxiliary building of a nuclear power plant due to an external impact by using the LS-DYNA finite element program. The wall of the auxiliary building is SC structure and the material of the SC wall plate is high manganese steel, which has superior ductility and energy absorbance compared to the ordinary steel used for other SC wall plates. The effects of the material of the wall, collision speed, and angle on the magnitude of the local damage were evaluated by local collision analysis. The analysis revealed that the SC wall made of manganese steel had significantly less damage than the SC wall made of ordinary steel. In conclusion, an SC wall made of manganese steel can have higher effective resistance than an SC wall made of ordinary steel against the local collision of an airplane engine or against a turbine impact.

Local Collision Simulation of an SC Wall Using Energy Absorbing Steel

Energy Technology Data Exchange (ETDEWEB)

Chung, Chulhun; Choi, Hyun; Park, Jaegyun [Dankook Univ., Yongin (Korea, Republic of)

2013-08-15

This study evaluates the local damage of a turbine in an auxiliary building of a nuclear power plant due to an external impact by using the LS-DYNA finite element program. The wall of the auxiliary building is SC structure and the material of the SC wall plate is high manganese steel, which has superior ductility and energy absorbance compared to the ordinary steel used for other SC wall plates. The effects of the material of the wall, collision speed, and angle on the magnitude of the local damage were evaluated by local collision analysis. The analysis revealed that the SC wall made of manganese steel had significantly less damage than the SC wall made of ordinary steel. In conclusion, an SC wall made of manganese steel can have higher effective resistance than an SC wall made of ordinary steel against the local collision of an airplane engine or against a turbine impact.

Atomic bonding and mechanical properties of Al-Mg-Zr-Sc alloy

Institute of Scientific and Technical Information of China (English)

高英俊; 班冬梅; 韩永剑; 钟夏平; 刘慧

2004-01-01

The valence electron structures of Al-Mg alloy with minor Sc and Zr were calculated according to the empirical electron theory(EET) in solid. The results show that because of the strong interaction of Al atom with Zr and Sc atom in melting during solidification, the Al3 Sc and Al3 (Sc1-xZrx) particles which act as heterogeneous nuclear are firstly crystallized in alloy to make grains refine. In progress of solidification, the Al-Sc, Al-Zr-Sc segregation regions are formed in solid solution matrix of Al-Mg alloy owing to the strong interaction of Al atom with Zr, Scatoms in bulk of alloy, so in the following homogenization treatment, the finer dispersed Al3 Sc and Al3 (Sc1-x Zrx) second-particles which are coherence with the matrix are precipitated in the segregation region. These finer second particles with the strong Al-Zr, Al-Sc covalent bonds can strengthen the covalent bonds in matrix of the alloy, and also enhance the hardness and strength of Al-Mg alloy. Those finer second-particles precipitated in interface of sub-grains can also strengthen the covalence bonds there, and effectively hinder the interface of sub-grains from migrating and restrain the sub-grains from growing, and cause better thermal stability of Al-Mg alloy.

MUON DETECTORS: ALIGNMENT

CERN Multimedia

G.Gomez.

Since June of 2009, the muon alignment group has focused on providing new alignment constants and on finalizing the hardware alignment reconstruction. Alignment constants for DTs and CSCs were provided for CRAFT09 data reprocessing. For DT chambers, the track-based alignment was repeated using CRAFT09 cosmic ray muons and validated using segment extrapolation and split cosmic tools. One difference with respect to the previous alignment is that only five degrees of freedom were aligned, leaving the rotation around the local x-axis to be better determined by the hardware system. Similarly, DT chambers poorly aligned by tracks (due to limited statistics) were aligned by a combination of photogrammetry and hardware-based alignment. For the CSC chambers, the hardware system provided alignment in global z and rotations about local x. Entire muon endcap rings were further corrected in the transverse plane (global x and y) by the track-based alignment. Single chamber track-based alignment suffers from poor statistic...

Thermal conditions within tree cavities in ponderosa pine (Pinus ponderosa) forests: potential implications for cavity users

Science.gov (United States)

Vierling, Kerri T.; Lorenz, Teresa J.; Cunningham, Patrick; Potterf, Kelsi

2017-11-01

Tree cavities provide critical roosting and breeding sites for multiple species, and thermal environments in these cavities are important to understand. Our objectives were to (1) describe thermal characteristics in cavities between June 3 and August 9, 2014, and (2) investigate the environmental factors that influence cavity temperatures. We placed iButtons in 84 different cavities in ponderosa pine (Pinus ponderosa) forests in central Washington, and took hourly measurements for at least 8 days in each cavity. Temperatures above 40 °C are generally lethal to developing avian embryos, and 18% of the cavities had internal temperatures of ≥ 40 °C for at least 1 h of each day. We modeled daily maximum cavity temperature, the amplitude of daily cavity temperatures, and the difference between the mean internal cavity and mean ambient temperatures as a function of several environmental variables. These variables included canopy cover, tree diameter at cavity height, cavity volume, entrance area, the hardness of the cavity body, the hardness of the cavity sill (which is the wood below the cavity entrance which forms the barrier between the cavity and the external environment), and sill width. Ambient temperature had the largest effect size for maximum cavity temperature and amplitude. Larger trees with harder sills may provide more thermally stable cavity environments, and decayed sills were positively associated with maximum cavity temperatures. Summer temperatures are projected to increase in this region, and additional research is needed to determine how the thermal environments of cavities will influence species occupancy, breeding, and survival.

Improved reactor cavity

International Nuclear Information System (INIS)

Katz, L.R.; Demarchais, W.E.

1984-01-01

A reactor pressure vessel disposed in a cavity has coolant inlet or outlet pipes extending through passages in the cavity walls and welded to pressure nozzles. The cavity wall has means for directing fluid away from a break at a weld away from the pressure vessel, and means for inhibiting flow of fluid toward the vessel. (author)

Conceptual Design of the Superconducting Proton Linac Short Cryo-module

CERN Document Server

Bourcey, N; Capatina, O; Azevedo, P; Montesinos, E; Parma, V; Renaglia, T; Vande Craen, A; Williams, L R; Weingarten, W; Rousselot, S; Duthil, P; Duchesne, P; Reynet, D; Dambre, P

2012-01-01

The Superconducting Proton Linac (SPL) is an R&amp;amp;D effort conducted by CERN in partnership with other international laboratories, aimed at developing key technologies for the construction of a multi-megawatt proton linac based on state-of-the-art Superconducting Radio Frequency technology, which would serve as a driver for new physics facilities such as neutrinos and radioactive ion beams. Amongst the main objectives of this effort, are the development of 704 MHz bulk niobium b=1 elliptical cavities, operating at 2 K and providing an accelerating field of 25 MV/m, and testing of a string of cavities integrated in a machine-type cryo-module. In an initial phase only four out of the eight cavities of an SPL cryo-module will be tested in a ½ length cryo-module developed for this purpose, and therefore called the Short Cryo-module. This paper presents the conceptual design of the SC, highlighting its innovative principles in terms of cavity supporting and alignment, and describes the integratio...

Microstructure evolution of the 1469 Al–Cu–Li–Sc alloy during homogenization

Energy Technology Data Exchange (ETDEWEB)

Jia, Min, E-mail: jm_lushan@163.com; Zheng, Ziqiao, E-mail: csu1469@163.com; Gong, Zhu, E-mail: start123gz@163.com

2014-11-25

Highlights: • The formation of the W phase (AlCuSc) was found in the 1469 Al-Cu–Li–Sc alloy. • The W phase formed during the homogenization process. • We model the formation process of the W phase. • The formation of the W phase consumes lots of Cu and Sc atoms. - Abstract: The present work aims to clarify the formation of the W phase (AlCuSc) and its formation time in the high Cu content alloy with Sc addition. The microstructure evolution during the two-step homogenization annealing process was investigated in the 1469 Al–Cu–Li–Sc alloy. No evidences of the Al{sub 3}Sc phase and the W phase were found in the solidification structure. The arrays of the W phases were found to form after homogenization. The AlCu phases with traces of Sc that formed during solidification suppose to be the precursor of the W phases, and then transform into the W phases by consuming the Sc atoms that fixed in the supersaturate solid solution. The formation of the W phase inhibits the precipitation of the Al{sub 3}Sc phase. A corresponding model of the W phase formation mechanism is proposed.

Optimization of the Geometric Beta for the SSR2 Cavities of the Project X

International Nuclear Information System (INIS)

Solyak, N.; Vostrikov, A.; Yakovlev, V.P.; Awida, M.H.; Berrutti, P.; Gonin, I.V.

2012-01-01

Project X based on the 3 GeV CW superconducting Linac and is currently in the R and D phase. The CW SC Linac starts from a low-energy SCRF section (2.1 - 165 MeV) containing three different types of resonators. HWR f = 162.5 MHz (2.1 - 11 MeV) having beta= 0.11, SSR1 f = 325 MHz (11 - 35 MeV) having beta = 0.21. In this paper we present the analysis that lead to the final design of SSR2 f = 325 MHz cavity (35 - 165 MeV). We present the results of optimization of the geometric beta and the comparison between single, double and triple spoke resonators used in Project X frontend. A β optimization has been carried out for the last spoke cavity section of Project X front end. The optimization process of β opt for a single spoke resonator family SSR2 shown that β opt = 0.47 looks better than the previous choice, which is β opt = 0.4. This change can save some cavities and provide the same final energy for this section, 160 MeV. Single double and triple spoke resonator performances have been compared. The best option is the single spoke resonator SSR2 because the NTTF of a multi-spoke resonator is much narrower than a single one. In the energy range considered (40-160 MeV) the most efficient resonator is the single spoke one.

Magnetic Compton scattering study of Laves phase ZrFe2 and Sc doped ZrFe2: Experiment and Green function based relativistic calculations

Science.gov (United States)

Bhatt, Samir; Mund, H. S.; Kumar, Kishor; Bapna, Komal; Dashora, Alpa; Itou, M.; Sakurai, Y.; Ahuja, B. L.

2018-05-01

Spin momentum densities of ferromagnetic ZrFe2 and Zr0.8Sc0.2Fe2 have been measured using magnetic Compton scattering with 182.65 keV circularly polarized synchrotron radiations. Site specific spin moments, which are responsible for the formation of total spin moment, have been deduced from Compton line shapes. At room temperature, the computed spin moment of ZrFe2 is found to be slightly higher than that of Sc doped ZrFe2 which is in consensus with the magnetization data. To compare the experimental data, we have also computed magnetic Compton profiles (MCPs), total and partial spin projected density of states (DOS) and the site specific spin moments using spin-polarized relativistic Korringa-Kohn-Rostoker method. It is observed that the spin moment at Fe site is aligned antiparallel to that of Zr site in both ZrFe2 and Zr0.8Sc0.2Fe2. The MCP results when compared with vibrating sample magnetometer based magnetization data, show a very small contribution of orbital moment in the formation of total magnetic moments in both the compounds. The DOS of ferromagnetic ground state of ZrFe2 and Zr0.8Sc0.2Fe2 are interpreted on the basis of a covalent magnetic model beyond the Stoner rigid band model. It appears that on alloying between a magnetic and a non-magnetic partner (with low valence), a polarization develops on the non-magnetic atom which is anti-parallel to that of the magnetic atom.

Development of SC structure modularization in Nuclear Power Plant

Energy Technology Data Exchange (ETDEWEB)

Mun, Taeyoup [Korea Hydro and Nuclear Power Co., Ltd., Seoul (Korea, Republic of)

2008-04-15

New Focus on NPP are Rising Concerns on Global Warming, Potential energy crisis (geo-political), Improved reliability and safety of nuclear power plant, Advent of Generation 3+ NPP technology and Economical Energy Resource. New NPPs are 6 units in Korea and 23 in Asia being built, 32 units being planned in China by 2020 (150 by 2050), 10 units being planned in US by 2020 and IAEA expects $200 billions on NPP construction next 25 years (up to 30% of total world energy). {open_square} SC(Steel Plate Concrete) structure {center_dot} Steel Plate is used as a Structural Element instead of Reinforcing Bars in RC {center_dot} SC structure consists of Steel Plate with Headed Studs. Connected by Tie-bars - The Primary Purpose of Tie-bars is to Stiffen and Hold Together the Plates during Construction Process - Headed Studs are Welded to the Inside of Steel Plate for composite action {open_square} Benefits of SC Structure {center_dot} Shorten Construction Duration for Re bar, Forming and Scaffolding Works {center_dot} Minimize Site Labors {center_dot} Improve the Construction Quality {center_dot} Enable Construction Sites to be kept Clean {open_square} SC Modularization {center_dot} Fit for Modular Construction for Structural Features {center_dot} Fit for Modular Construction for Structural Features {center_dot} Inattentively Effective for Integrated Modules {center_dot} Pre-fabrication, Pre-assembly and Modularization {open_square} Project Overview {center_dot} Project Name: Development of SC structure for Modularization in NPP {center_dot} Project Type: Electric Power Industry R and D (Ministry of Knowledge Economy) {center_dot} Duration: Sep. 2005 {approx} Aug. 2008 (36 Months) {center_dot} Research Team and Scopes - Project Management: Korea Hydro and Nuclear Power Company (KHNP) - Development of Code and Standards for SC Structure: Korea Society of Steel Construction (KSSC) Korea Electric Power Research Institute (KEPRI) - Development of SC Structural Analysis and Design

Lightweight hydrogen-storage material Mg0.65Sc0.35D2 studied with 2H and 2H–{45Sc} MAS NMR exchange spectroscopy

NARCIS (Netherlands)

Srinivasan, S.; Magusin, P.C.M.M.

2011-01-01

Using double-quantum 2H MAS NMR with 45Sc recoupling and Bloch–Siegert compensated 2H–{45Sc} TRAPDOR we have identified the overlapping NMR signals of deuterium with and without scandium neighbors in Mg0.65Sc0.35D2, a candidate lightweight material for hydrogen storage. At room temperature we also

accelerating cavity

CERN Multimedia

On the inside of the cavity there is a layer of niobium. Operating at 4.2 degrees above absolute zero, the niobium is superconducting and carries an accelerating field of 6 million volts per metre with negligible losses. Each cavity has a surface of 6 m2. The niobium layer is only 1.2 microns thick, ten times thinner than a hair. Such a large area had never been coated to such a high accuracy. A speck of dust could ruin the performance of the whole cavity so the work had to be done in an extremely clean environment.

Role of cell death in the propagation of PrP(Sc) in immune cells.

Science.gov (United States)

Takahashi, Kenichi; Inoshima, Yasuo; Ishiguro, Naotaka

2015-03-01

A number of studies have suggested that macrophages, dendritic cells, and follicular dendritic cells play an important role in the propagation of PrP(Sc). Both accumulation and proteolysis of PrP(Sc) have been demonstrated in peripheral macrophages. Macrophages may act as reservoirs for PrP(Sc) particles if the cells die during transient PrP(Sc) propagation. However, whether cell death plays a role in PrP(Sc) propagation in macrophages remains unclear. In this study, we investigated the possibility of propagation and transmission of PrP(Sc) between dead immune cells and living neural cells. We found that under specific conditions, transient PrP(Sc) propagation occurs in dead cells, indicating that interaction between PrP(C) and PrP(Sc) on plasma membrane lipid rafts might be important for PrP(Sc) propagation. Co-culturing of killed donor PrP(Sc)-infected macrophages with recipient N2a-3 neuroblastoma cells accelerated PrP(Sc) transmission. Our results suggest that cell death may play an important role in PrP(Sc) propagation, whereas transient PrP(Sc) propagation in macrophages has little effect on PrP(Sc) transmission.

CERN Technical Training 2004: New Short Courses (SC) on Microsoft Outlook

CERN Multimedia

Monique Duval

2004-01-01

The CERN Technical Training programme is now proposing a new format for courses on Microsoft Outlook. Three two-hours Short Courses (SC) will cover basic and advanced functionalities of the recommended mail client for email at CERN. Each module can be followed independently. The next scheduled sessions will take place as follows: Outlook (SC I): E-mail. Next session: 22.10.2004 (9h00-11h00) Outlook (SC II): Calendar, Tasks and Notes. Next session: 22.10.2004 (14h00-16h00) Outlook (SC III): Meetings and Delegation. Next session: 9.11.2004 (14h00-16h00) In particular, SC I will cover how to open, create and send email, work with attachments, use stationery, organise mail, and work with the address book, SC II will show how to work with the calendar, tasks and notes, and SC III will cover how to organise and manage meetings, work with meeting requests, share tasks, and use email and calendar delegation. The number of participants to each session is limited to 8. The instructor is English-French bilingual, and...

Long bunch trains measured using a prototype cavity beam position monitor for the Compact Linear Collider

Directory of Open Access Journals (Sweden)

F. J. Cullinan

2015-11-01

Full Text Available The Compact Linear Collider (CLIC requires beam position monitors (BPMs with 50 nm spatial resolution for alignment of the beam line elements in the main linac and beam delivery system. Furthermore, the BPMs must be able to make multiple independent measurements within a single 156 ns long bunch train. A prototype cavity BPM for CLIC has been manufactured and tested on the probe beam line at the 3rd CLIC Test Facility (CTF3 at CERN. The transverse beam position is determined from the electromagnetic resonant modes excited by the beam in the two cavities of the pickup, the position cavity and the reference cavity. The mode that is measured in each cavity resonates at 15 GHz and has a loaded quality factor that is below 200. Analytical expressions for the amplitude, phase and total energy of signals from long trains of bunches have been derived and the main conclusions are discussed. The results of the beam tests are presented. The variable gain of the receiver electronics has been characterized using beam excited signals and the form of the signals for different beam pulse lengths with the 2/3  ns bunch spacing has been observed. The sensitivity of the reference cavity signal to charge and the horizontal position signal to beam offset have been measured and are compared with theoretical predictions based on laboratory measurements of the BPM pickup and the form of the resonant cavity modes as determined by numerical simulation. Finally, the BPM was calibrated so that the beam position jitter at the BPM location could be measured. It is expected that the beam jitter scales linearly with the beam size and so the results are compared to predicted values for the latter.

Long bunch trains measured using a prototype cavity beam position monitor for the Compact Linear Collider

Science.gov (United States)

Cullinan, F. J.; Boogert, S. T.; Farabolini, W.; Lefevre, T.; Lunin, A.; Lyapin, A.; Søby, L.; Towler, J.; Wendt, M.

2015-11-01

The Compact Linear Collider (CLIC) requires beam position monitors (BPMs) with 50 nm spatial resolution for alignment of the beam line elements in the main linac and beam delivery system. Furthermore, the BPMs must be able to make multiple independent measurements within a single 156 ns long bunch train. A prototype cavity BPM for CLIC has been manufactured and tested on the probe beam line at the 3rd CLIC Test Facility (CTF3) at CERN. The transverse beam position is determined from the electromagnetic resonant modes excited by the beam in the two cavities of the pickup, the position cavity and the reference cavity. The mode that is measured in each cavity resonates at 15 GHz and has a loaded quality factor that is below 200. Analytical expressions for the amplitude, phase and total energy of signals from long trains of bunches have been derived and the main conclusions are discussed. The results of the beam tests are presented. The variable gain of the receiver electronics has been characterized using beam excited signals and the form of the signals for different beam pulse lengths with the 2 /3 ns bunch spacing has been observed. The sensitivity of the reference cavity signal to charge and the horizontal position signal to beam offset have been measured and are compared with theoretical predictions based on laboratory measurements of the BPM pickup and the form of the resonant cavity modes as determined by numerical simulation. Finally, the BPM was calibrated so that the beam position jitter at the BPM location could be measured. It is expected that the beam jitter scales linearly with the beam size and so the results are compared to predicted values for the latter.

Formatt: Correcting protein multiple structural alignments by incorporating sequence alignment

Directory of Open Access Journals (Sweden)

Daniels Noah M

2012-10-01

Full Text Available Abstract Background The quality of multiple protein structure alignments are usually computed and assessed based on geometric functions of the coordinates of the backbone atoms from the protein chains. These purely geometric methods do not utilize directly protein sequence similarity, and in fact, determining the proper way to incorporate sequence similarity measures into the construction and assessment of protein multiple structure alignments has proved surprisingly difficult. Results We present Formatt, a multiple structure alignment based on the Matt purely geometric multiple structure alignment program, that also takes into account sequence similarity when constructing alignments. We show that Formatt outperforms Matt and other popular structure alignment programs on the popular HOMSTRAD benchmark. For the SABMark twilight zone benchmark set that captures more remote homology, Formatt and Matt outperform other programs; depending on choice of embedded sequence aligner, Formatt produces either better sequence and structural alignments with a smaller core size than Matt, or similarly sized alignments with better sequence similarity, for a small cost in average RMSD. Conclusions Considering sequence information as well as purely geometric information seems to improve quality of multiple structure alignments, though defining what constitutes the best alignment when sequence and structural measures would suggest different alignments remains a difficult open question.

Frequency-feedback cavity enhanced spectrometer

Science.gov (United States)

Hovde, David Christian; Gomez, Anthony

2015-08-18

A spectrometer comprising an optical cavity, a light source capable of producing light at one or more wavelengths transmitted by the cavity and with the light directed at the cavity, a detector and optics positioned to collect light transmitted by the cavity, feedback electronics causing oscillation of amplitude of the optical signal on the detector at a frequency that depends on cavity losses, and a sensor measuring the oscillation frequency to determine the cavity losses.

Experimental Results from a Microwave Cavity Beam Position Monitor

International Nuclear Information System (INIS)

Balakin, V.; Bazhan, A.; Lunev, P.; Solyak, N.; Vogel, V.; Zhogolev, P.; Lisitsyn, A.; Yakimenko, V.

1999-01-01

Future Linear Colliders have hard requirements for the beam transverse position stability in the accelerator. A beam Position Monitor (BPM) with the resolution better than 0.1 micron in the single bunch regime is needed to control the stability of the beam position along the linac. Proposed BPM is based on the measurement of the asymmetrical mode excited by single bunch in the cavity. Four stages of signal processing (space-, time-, frequency- and phase-filtering providing the required signal-to-noise ratio) are used to obtain extremely high resolution. The measurement set-up was designed by BINP and installed at ATF/BNL to test experimentally this concept. The set-up includes three two-coordinates BPM's at the frequency of 13.566 GHz, and reference intensity/phase cavity. BPM's were mounted on support table. The two-coordinates movers allow to move and align BPM's along the straight line, using the signals from the beam. The position of each monitor is controlled by the sensors with the accuracy 0.03 micron. The information from three monitors allows to exclude angle and position jitter of the beam and measure BPM resolution. In the experiments the resolution of about 0.15 micron for 0.25 nC beam intensity was obtained, that is close to the value required

Electrochemical Characterization of Ni/(Sc)YSZ Electrodes

DEFF Research Database (Denmark)

Ramos, Tania; Thydén, Karl Tor Sune; Mogensen, Mogens Bjerg

2010-01-01

Investigations of Ni/(Sc)YSZ cermets for solid oxide cells (SOCs) were performed by electrochemical impedance spectroscopy (EIS), under varying experimental conditions and upon redox cycling, using three different designs of symmetric cells. The deconvolution and fitting of the obtained impedance...... parameters. Initial degradation results for both Ni/ScYSZ and Ni/YSZ based anodes under very high steam content are also reported. ©2010 COPYRIGHT ECS - The Electrochemical Society...

One-Step Partially Purified Lipases (ScLipA and ScLipB from Schizophyllum commune UTARA1 Obtained via Solid State Fermentation and Their Applications

Directory of Open Access Journals (Sweden)

Yew Chee Kam

2017-12-01

Full Text Available Lipases with unique characteristics are of value in industrial applications, especially those targeting cost-effectiveness and less downstream processes. The aims of this research were to: (i optimize the fermentation parameters via solid state fermentation (SSF; and (ii study the performance in hydrolysis and esterification processes of the one-step partially purified Schizophyllum commune UTARA1 lipases. Lipase was produced by cultivating S. commune UTARA1 on sugarcane bagasse (SB with used cooking oil (UCO via SSF and its production was optimized using Design-Expert® 7.0.0. Fractions 30% (ScLipA and 70% (ScLipB which contained high lipase activity were obtained by stepwise (NH42SO4 precipitation. Crude fish oil, coconut oil and butter were used to investigate the lipase hydrolysis capabilities by a free glycerol assay. Results showed that ScLipA has affinities for long, medium and short chain triglycerides, as all the oils investigated were degraded, whereas ScLipB has affinities for long chain triglycerides as it only degrades crude fish oil. During esterification, ScLipA was able to synthesize trilaurin and triacetin. Conversely, ScLipB was specific towards the formation of 2-mono-olein and triacetin. From the results obtained, it was determined that ScLipA and ScLipB are sn-2 regioselective lipases. Hence, the one-step partial purification strategy proved to be feasible for partial purification of S. commune UTARA1 lipases that has potential use in industrial applications.

Segmentation of multiple heart cavities in 3-D transesophageal ultrasound images.

Science.gov (United States)

Haak, Alexander; Vegas-Sánchez-Ferrero, Gonzalo; Mulder, Harriët W; Ren, Ben; Kirişli, Hortense A; Metz, Coert; van Burken, Gerard; van Stralen, Marijn; Pluim, Josien P W; van der Steen, Antonius F W; van Walsum, Theo; Bosch, Johannes G

2015-06-01

Three-dimensional transesophageal echocardiography (TEE) is an excellent modality for real-time visualization of the heart and monitoring of interventions. To improve the usability of 3-D TEE for intervention monitoring and catheter guidance, automated segmentation is desired. However, 3-D TEE segmentation is still a challenging task due to the complex anatomy with multiple cavities, the limited TEE field of view, and typical ultrasound artifacts. We propose to segment all cavities within the TEE view with a multi-cavity active shape model (ASM) in conjunction with a tissue/blood classification based on a gamma mixture model (GMM). 3-D TEE image data of twenty patients were acquired with a Philips X7-2t matrix TEE probe. Tissue probability maps were estimated by a two-class (blood/tissue) GMM. A statistical shape model containing the left ventricle, right ventricle, left atrium, right atrium, and aorta was derived from computed tomography angiography (CTA) segmentations by principal component analysis. ASMs of the whole heart and individual cavities were generated and consecutively fitted to tissue probability maps. First, an average whole-heart model was aligned with the 3-D TEE based on three manually indicated anatomical landmarks. Second, pose and shape of the whole-heart ASM were fitted by a weighted update scheme excluding parts outside of the image sector. Third, pose and shape of ASM for individual heart cavities were initialized by the previous whole heart ASM and updated in a regularized manner to fit the tissue probability maps. The ASM segmentations were validated against manual outlines by two observers and CTA derived segmentations. Dice coefficients and point-to-surface distances were used to determine segmentation accuracy. ASM segmentations were successful in 19 of 20 cases. The median Dice coefficient for all successful segmentations versus the average observer ranged from 90% to 71% compared with an inter-observer range of 95% to 84%. The

Baculovirus display of single chain antibody (scFv using a novel signal peptide

Directory of Open Access Journals (Sweden)

Gonzalez Gaëlle

2010-11-01

Full Text Available Abstract Background Cells permissive to virus can become refractory to viral replication upon intracellular expression of single chain fragment variable (scFv antibodies directed towards viral structural or regulatory proteins, or virus-coded enzymes. For example, an intrabody derived from MH-SVM33, a monoclonal antibody against a conserved C-terminal epitope of the HIV-1 matrix protein (MAp17, was found to exert an inhibitory effect on HIV-1 replication. Results Two versions of MH-SVM33-derived scFv were constructed in recombinant baculoviruses (BVs and expressed in BV-infected Sf9 cells, N-myristoylation-competent scFvG2/p17 and N-myristoylation-incompetent scFvE2/p17 protein, both carrying a C-terminal HA tag. ScFvG2/p17 expression resulted in an insoluble, membrane-associated protein, whereas scFvE2/p17 was recovered in both soluble and membrane-incorporated forms. When coexpressed with the HIV-1 Pr55Gag precursor, scFvG2/p17 and scFvE2/p17 did not show any detectable negative effect on virus-like particle (VLP assembly and egress, and both failed to be encapsidated in VLP. However, soluble scFvE2/p17 isolated from Sf9 cell lysates was capable of binding to its specific antigen, in the form of a synthetic p17 peptide or as Gag polyprotein-embedded epitope. Significant amounts of scFvE2/p17 were released in the extracellular medium of BV-infected cells in high-molecular weight, pelletable form. This particulate form corresponded to BV particles displaying scFvE2/p17 molecules, inserted into the BV envelope via the scFv N-terminal region. The BV-displayed scFvE2/p17 molecules were found to be immunologically functional, as they reacted with the C-terminal epitope of MAp17. Fusion of the N-terminal 18 amino acid residues from the scFvE2/p17 sequence (N18E2 to another scFv recognizing CD147 (scFv-M6-1B9 conferred the property of BV-display to the resulting chimeric scFv-N18E2/M6. Conclusion Expression of scFvE2/p17 in insect cells using a BV

IEC SC15E: Report on liaison activities of CIGRÉ-SC15

DEFF Research Database (Denmark)

Henriksen, Mogens

2000-01-01

WG’s activities under CIGRÉ SC15:WG 15.01 - Fluid impregnated systems.WG 15.02 - Dielectric Liquids.WG 15.03 - Gas Insulation.WG 15.04 - Outdoor Insulation.WG 15.05 - Capacitors.WG 15.07 - Solid Insulating Materials for Rotating Machines.WG 15/33.08 - Insulation Monitoring and Life Estimation. WG...

MUON DETECTORS: ALIGNMENT

CERN Multimedia

G.Gomez

2010-01-01

The main developments in muon alignment since March 2010 have been the production, approval and deployment of alignment constants for the ICHEP data reprocessing. In the barrel, a new geometry, combining information from both hardware and track-based alignment systems, has been developed for the first time. The hardware alignment provides an initial DT geometry, which is then anchored as a rigid solid, using the link alignment system, to a reference frame common to the tracker. The “GlobalPositionRecords” for both the Tracker and Muon systems are being used for the first time, and the initial tracker-muon relative positioning, based on the link alignment, yields good results within the photogrammetry uncertainties of the Tracker and alignment ring positions. For the first time, the optical and track-based alignments show good agreement between them; the optical alignment being refined by the track-based alignment. The resulting geometry is the most complete to date, aligning all 250 DTs, ...

Superconducting accelerating structures for very low velocity ion beams

Energy Technology Data Exchange (ETDEWEB)

Xu, J.; Shepard, K.W.; Ostroumov, P.N.; Fuerst, J.D.; Waldschmidt, G.; /Argonne; Gonin, I.V.; /Fermilab

2008-01-01

This paper presents designs for four types of very-low-velocity superconducting accelerating cavity capable of providing several MV of accelerating potential per cavity, and suitable for particle velocities in the range 0.006 < v/c < 0.06. Superconducting TEM-class cavities have been widely applied to CW acceleration of ion beams. SC linacs can be formed as an array of independently-phased cavities, enabling a variable velocity profile to maximize the output energy for each of a number of different ion species. Several laboratories in the US and Europe are planning exotic beam facilities based on SC linacs. The cavity designs presented here are intended for the front-end of such linacs, particularly for the post-acceleration of rare isotopes of low charge state. Several types of SC cavities have been developed recently to cover particle velocities above 0.06c. Superconducting four-gap quarter-wave resonators for velocities 0.008 < {beta} = v/c < 0.05 were developed about two decades ago and have been successfully operated at the ATLAS SC linac at Argonne National Laboratory. Since that time, progress in simulation tools, cavity fabrication and processing have increased SC cavity gradients by a factor of 3-4. This paper applies these tools to optimize the design of a four-gap quarter-wave resonator for exotic beam facilities and other low-velocity applications.

Laser photoelectron spectrometry of Sc- and Y-

International Nuclear Information System (INIS)

Feigerle, C.S.; Herman, Z.; Lineberger, W.C.

1981-01-01

The photoelectron spectra of Sc - and Y - have been obtained in a crossed ion- and laser-beam experiment. Analysis of the Sc - spectrum yields two bound terms of 3d4s 2 4p configuration ( 1 D 0 and 3 D 0 ), with EA(Sc) = 0.189 +- 0.020 eV and an excited-state binding energy of 0.042 +- 0.020 eV. Similarly, the (4d5s 2 5p) 1 D 0 ground state of Y - is bound by 0.308 +- 0.012 eV and a (4d5s 2 5p) 3 D 0 excited term is bound by 0.165 +- 0.025 eV. With the determination of the bound electronic configuration of Sc - as 3d4s 2 4p, the order of filling of electron shells of the first transition series negative ions is found to be 4s 2 ep, 3d4s 2 4p, the order of filling of electron shells of the first transition series negative ions is found to be 4s 2 4p, 3d4s 2 4p, followed by 3dsup(k) 4s 2 (k = 3, 4, ..., 10). (orig.)

The SC gets ready for visitors

CERN Multimedia

Antonella Del Rosso

2012-01-01

Hall 300, which houses the Synchrocyclotron (SC), CERN’s first accelerator, is getting ready to host a brand-new exhibition. The site will be one of the stops on the new visit itineraries that will be inaugurated for the 2013 CERN Open Day.   The Synchrocyclotron through the years. Just as it did in the late 1950s, when the accelerator was first installed, the gigantic red structure of the Synchrocyclotron's magnet occupies a large part of the 300-square-metre hall. “We have completed the first phase of the project that will give the SC a new lease of life,” says Marco Silari, the project leader and a member of CERN’s Radiation Protection Group. “We have removed all the equipment that was not an integral part of the accelerator. The hall is now ready for the civil-engineering work that will precede the installation of the exhibition.” The SC was witness to a big part of the history of CERN. The accelerator produced ...

Beam orbit control in TESLA superconducting cavities from dipole mode measurements

International Nuclear Information System (INIS)

Paparella, R.

2006-09-01

the last chapter. A time domain HOM data acquisition setup has been conceived at SLAC and fabricated with the additional help of DESY and Cea. The beam has been moved by pairs of correctors for each transverse plane by using a system capable of monitoring simultaneously one dipole mode from all 40 cavities at TTF. HOM signals have been used for beam position monitoring and alignment, and cavity relative misalignments in the cold modules has been measured. The results of this study, prove the benefit and the usefulness of using dipole modes as beam position monitor and to provide a cross-check of the mechanical measurements. (author)

Fabrication of mm-wave undulator cavities using deep x-ray lithography

International Nuclear Information System (INIS)

Song, J.; Feinerman, A.; Kang, Y.; Kustom, R.; Lai, B.; Nassiri, A.; White, V.; Well, G.M.

1996-01-01

The possibility of fabricating mm-wave radio frequency cavities (100 endash 300 GHz) using deep x-ray lithography (DXRL) is being investigated. The fabrication process includes manufacture of precision x-ray masks, exposure of positive resist by x-ray through the mask, resist development, and electroforming of the final microstructure. Highly precise, two-dimensional features can be machined onto wafers using DXRL. Major challenges are: fabrication of the wafers into three-dimensional rf structures; alignment and overlay accuracy of structures; adhesion of the PMMA on the copper substrate; and selection of a developer to obtain high resolution. Rectangular cavity geometry is best suited to this fabrication technique. A 30- or 84-cell 108-GHz mm-wave structure can serve as an electromagnetic undulator. A mm-wave undulator, which will be discussed later, may have special features compared to the conventional undulator. First harmonic undulator radiation at 5.2 keV would be possible using the Advanced Photon Source (APS) linac system, which provides a low-emittance electron beam by using an rf thermionic gun with an energy as high as 750 MeV. More detailed rf simulation, heat extraction analysis, beam dynamics using a mm-wave structure, and measurements on 10x larger scale models can be found in these proceedings [Y.W. Kang et al., open-quote open-quote Design and Construction of Planar mm-wave Accelerating Cavity Structures close-quote close-quote] copyright 1996 American Institute of Physics

Experimental investigation of cavity flows

Energy Technology Data Exchange (ETDEWEB)

Loeland, Tore

1998-12-31

This thesis uses LDV (Laser Doppler Velocimetry), PIV (Particle Image Velocimetry) and Laser Sheet flow Visualisation to study flow inside three different cavity configurations. For sloping cavities, the vortex structure inside the cavities is found to depend upon the flow direction past the cavity. The shape of the downstream corner is a key factor in destroying the boundary layer flow entering the cavity. The experimental results agree well with numerical simulations of the same geometrical configurations. The results of the investigations are used to find the influence of the cavity flow on the accuracy of the ultrasonic flowmeter. A method to compensate for the cavity velocities is suggested. It is found that the relative deviation caused by the cavity velocities depend linearly on the pipe flow. It appears that the flow inside the cavities should not be neglected as done in the draft for the ISO technical report on ultrasonic flowmeters. 58 refs., 147 figs., 2 tabs.

Experimental investigation of cavity flows

Energy Technology Data Exchange (ETDEWEB)

Loeland, Tore

1999-12-31

This thesis uses LDV (Laser Doppler Velocimetry), PIV (Particle Image Velocimetry) and Laser Sheet flow Visualisation to study flow inside three different cavity configurations. For sloping cavities, the vortex structure inside the cavities is found to depend upon the flow direction past the cavity. The shape of the downstream corner is a key factor in destroying the boundary layer flow entering the cavity. The experimental results agree well with numerical simulations of the same geometrical configurations. The results of the investigations are used to find the influence of the cavity flow on the accuracy of the ultrasonic flowmeter. A method to compensate for the cavity velocities is suggested. It is found that the relative deviation caused by the cavity velocities depend linearly on the pipe flow. It appears that the flow inside the cavities should not be neglected as done in the draft for the ISO technical report on ultrasonic flowmeters. 58 refs., 147 figs., 2 tabs.

Early 500 MHz prototype LEP RF Cavity with superposed storage cavity

CERN Multimedia

CERN PhotoLab

1981-01-01

The principle of transferring the RF power back and forth between the accelerating cavity and a side-coupled storage cavity was demonstrated with this 500 MHz prototype. In LEP, the accelerating frequency was 352.2 MHz, and accelerating and storage cavities were consequently larger. See also 8002294, 8006061, 8407619X, and Annual Reports 1980, p.115; 1981, p.95; 1985, vol.I, p.13.

CERN Technical Training 2004: New Short Courses (SC) on Microsoft Outlook

CERN Multimedia

Monique Duval

2004-01-01

The CERN Technical Training programme is now proposing a new format for courses on Microsoft Outlook. Three two-hours Short Courses (SC) will cover basic and advanced functionalities of the recommended mail client for email at CERN. Each module can be followed independently. The next scheduled sessions will take place as follows: Outlook (SC I): E-mail. Next session: 31.8.2004 (9h00-11h00) Outlook (SC II): Calendar, Tasks and Notes. Next session: 31.8.2004 (14h00-16h00) Outlook (SC III): Meetings and Delegation. Next session: 7.9.2004 (14h00-16h00) In particular, SC I will cover how to open, create and send email, work with attachments, use stationery, organise mail, and work with the address book, SC II will show how to work with the calendar, tasks and notes, and SC III will cover how to organise and manage meetings, work with meeting requests, share tasks, and use email and calendar delegation. The number of participants to each session is limited to 8. The instructor is English-French bilingual, and she...

Aldehyde dehydrogenase 1 is a marker for normal and malignant human colonic stem cells (SC) and tracks SC overpopulation during colon tumorigenesis.

Science.gov (United States)

Huang, Emina H; Hynes, Mark J; Zhang, Tao; Ginestier, Christophe; Dontu, Gabriela; Appelman, Henry; Fields, Jeremy Z; Wicha, Max S; Boman, Bruce M

2009-04-15

Although the concept that cancers originate from stem cells (SC) is becoming scientifically accepted, mechanisms by which SC contribute to tumor initiation and progression are largely unknown. For colorectal cancer (CRC), investigation of this problem has been hindered by a paucity of specific markers for identification and isolation of SC from normal and malignant colon. Accordingly, aldehyde dehydrogenase 1 (ALDH1) was investigated as a possible marker for identifying colonic SC and for tracking them during cancer progression. Immunostaining showed that ALDH1(+) cells are sparse and limited to the normal crypt bottom, where SCs reside. During progression from normal epithelium to mutant (APC) epithelium to adenoma, ALDH1(+) cells increased in number and became distributed farther up the crypt. CD133(+) and CD44(+) cells, which are more numerous and broadly distributed in normal crypts, showed similar changes during tumorigenesis. Flow cytometric isolation of cancer cells based on enzymatic activity of ALDH (Aldefluor assay) and implantation of these cells in nonobese diabetic-severe combined immunodeficient mice (a) generated xenograft tumors (Aldefluor(-) cells did not), (b) generated them after implanting as few as 25 cells, and (c) generated them dose dependently. Further isolation of cancer cells using a second marker (CD44(+) or CD133(+) serially) only modestly increased enrichment based on tumor-initiating ability. Thus, ALDH1 seems to be a specific marker for identifying, isolating, and tracking human colonic SC during CRC development. These findings also support our original hypothesis, derived previously from mathematical modeling of crypt dynamics, that progressive colonic SC overpopulation occurs during colon tumorigenesis and drives CRC development.

SPS RF Accelerating Cavity

CERN Multimedia

1979-01-01

This picture shows one of the 2 new cavities installed in 1978-1979. The main RF-system of the SPS comprises four cavities: two of 20 m length and two of 16.5 m length. They are all installed in one long straight section (LSS 3). These cavities are of the travelling-wave type operating at a centre frequency of 200.2 MHz. They are wideband, filling time about 700 ns and untuned. The power amplifiers, using tetrodes are installed in a surface building 200 m from the cavities. Initially only two cavities were installed, a third cavity was installed in 1978 and a forth one in 1979. The number of power amplifiers was also increased: to the first 2 MW plant a second 2 MW plant was added and by end 1979 there were 8 500 kW units combined in pairs to feed each of the 4 cavities with up to about 1 MW RF power, resulting in a total accelerating voltage of about 8 MV. See also 7412016X, 7412017X, 7411048X

Polymorphous GdScO3 as high permittivity dielectric

International Nuclear Information System (INIS)

Schäfer, A.; Rahmanizadeh, K.; Bihlmayer, G.; Luysberg, M.; Wendt, F.; Besmehn, A.; Fox, A.

2015-01-01

Four different polymorphs of GdScO 3 are assessed theoretically and experimentally with respect to their suitability as a dielectric. The calculations carried out by density functional theory reveal lattice constants, band gaps and the energies of formation of three crystal phases. Experimentally all three crystal phases and the amorphous phase can be realized as thin films by pulsed laser deposition using various growth templates. Their respective crystal structures are confirmed by X-ray diffraction and transmission electron microscopy reflecting the calculated lattice constants. X-ray photoelectron spectroscopy unveils the band gaps of the different polymorphs of GdScO 3 which are above 5 eV for all films demonstrating good insulating properties. From capacitance voltage measurements, high permittivities of up to 27 for hexagonal GdScO 3 are deduced. - Highlights: • Different epitaxial polymorph phases of GdScO 3 were grown by pulsed laser deposition. • The cubic phase of GdScO 3 is reported for the first time. • All phases are proven to be useful for the use in silicon based and III–V based microelectronic devices.

Piezoelectric coefficients and spontaneous polarization of ScAlN

International Nuclear Information System (INIS)

Caro, Miguel A; Laurila, Tomi; Zhang, Siyuan; Moram, Michelle A; Riekkinen, Tommi; Ylilammi, Markku; Molarius, Jyrki; Lopez-Acevedo, Olga

2015-01-01

We present a computational study of spontaneous polarization and piezoelectricity in Sc x Al 1−x N alloys in the compositional range from x = 0 to x = 0.5, obtained in the context of density functional theory and the Berry-phase theory of electric polarization using large periodic supercells. We report composition-dependent values of piezoelectric coefficients e ij , piezoelectric moduli d ij and elastic constants C ij . The theoretical findings are complemented with experimental measurement of e 33 for a series of sputtered ScAlN films carried out with a piezoelectric resonator. The rapid increase with Sc content of the piezoelectric response reported in previous studies is confirmed for the available data. A detailed description of the full methodology required to calculate the piezoelectric properties of ScAlN, with application to other complex alloys, is presented. In particular, we find that the large amount of internal strain present in ScAlN and its intricate relation with electric polarization make configurational sampling and the use of large supercells at different compositions necessary in order to accurately derive the piezoelectric response of the material. (paper)

The SC15 protein of Schizophyllum commune mediates formation of aerial hyphae and attachment in the absence of the SC3 hydrophobin

NARCIS (Netherlands)

Lugones, L G; de Jong, J F; de Vries, O M H; Jalving, R; Dijksterhuis, J; Wösten, H A B

Disruption of the SC3 gene in the basidiomycete Schizophyllum commune affected not only formation of aerial hyphae but also attachment to hydrophobic surfaces. However, these processes were not completely abolished, indicating involvement of other molecules. We here show that the SC15 protein

FRACTIONAL RECRYSTALLIZATION KINETICS IN DIRECTLY COLD ROLLED Al-Mg, Al-Mg-Sc AND Al-Mg-Sc-Zr ALLOY

Directory of Open Access Journals (Sweden)

M. S. Kaiser

2014-12-01

Full Text Available The evaluation of texture as a function of recrystallization has been characterized for directly cold rolled Al-6Mg, Al-6Mg-0.4Sc and Al-6Mg-0.4Sc-0.2Zr alloys. Samples were annealed isothermally at 400 °C for 1 to 240 minutes to allow recrystallization. Recrystallization kinetics of the alloys is analyzed from the micro-hardness variation. Isothermally annealed samples of aluminum alloys were also studied using JMAK type analysis to see if there exists any correlation between the methods. Recrystallization fraction behavior between two methods the scandium added alloys show the higher variation due to precipitation hardening and higher recrystallization behavior. The scandium and zirconium as a combined shows the more variation due to formation of Al3(Sc, Zr precipitate. From the microstructure it is also observed that the base Al-Mg alloy attained almost fully re-crystallized state after annealing at 400 °C for 60 minutes

Creep properties and precipitate evolution in Al-Li alloys microalloyed with Sc and Yb

Energy Technology Data Exchange (ETDEWEB)

Krug, Matthew E. [Department of Materials Science and Engineering, Northwestern University, 2220 Campus Drive, Evanston, IL 60208 (United States); Seidman, David N. [Department of Materials Science and Engineering, Northwestern University, 2220 Campus Drive, Evanston, IL 60208 (United States); Northwestern Center for Atom Probe Tomography, Northwestern University, 2220 Campus Drive, Evanston, IL 60208 (United States); Dunand, David C., E-mail: dunand@northwestern.edu [Department of Materials Science and Engineering, Northwestern University, 2220 Campus Drive, Evanston, IL 60208 (United States)

2012-07-30

Highlights: Black-Right-Pointing-Pointer We examine the creep behavior of Al-alloys with Li and rare earth element additions. Black-Right-Pointing-Pointer These alloys exhibit threshold stresses below which no measurable creep occurs. Black-Right-Pointing-Pointer Larger precipitate size and lattice parameter mismatch increase creep resistance. Black-Right-Pointing-Pointer A simple parameter describes the threshold stress behavior in ternary Al-Sc-X alloys. Black-Right-Pointing-Pointer The findings are explained by a recent model of dislocation-precipitate interactions. - Abstract: A dilute Al-Sc alloy (Al-0.12 Sc, at.%, Al-Sc), its counterpart with a Li addition (Al-2.9 Li-0.11 Sc, at.%, Al-Li-Sc), as well as a quaternary alloy (Al-5.53 Li-0.048 Sc-0.009 Yb, at.%, Al-Li-Sc-Yb) were isothermally aged at 325 Degree-Sign C, and in some cases isochronally aged to 450 Degree-Sign C. As the {alpha} Prime -Al{sub 3}(Li,Sc) and Al{sub 3}(Li,Sc,Yb) precipitates, with L1{sub 2} structure, coarsen in the two Li-containing alloys, their Li and Yb concentrations decrease and their Sc concentration increases. A significant interfacial excess of Li also segregates at the {alpha}-Al matrix/{alpha} Prime -Al{sub 3}Sc(Li,Sc,Yb) precipitate interface: 5.99 {+-} 0.05 atoms nm{sup -2} in Al-Li-Sc and 13.2 {+-} 0.4 atoms nm{sup -2} in Al-Li-Sc-Yb after aging isochronally to 450 Degree-Sign C. During compression creep at 300 Degree-Sign C, the aged alloys exhibit threshold stresses between 8 and 22 MPa. A recent threshold stress model based on elastic interactions between dislocations and precipitates predicts correctly that Li additions in the Al-Li-Sc alloy reduce the threshold stress, while Yb in the Al-Li-Sc-Yb alloy increases it. The model is also in agreement with the threshold stresses of all Al-Sc-X alloys published to date.

SPS accelerating cavity

CERN Multimedia

CERN PhotoLab

1976-01-01

The SPS started up with 2 accelerating cavities (each consisting of 5 tank sections) in LSS3. They have a 200 MHz travelling wave structure (see 7411032 and 7802190) and 750 kW of power is fed to each of the cavities from a 1 MW tetrode power amplifier, located in a surface building above, via a coaxial transmission line. Clemens Zettler, builder of the SPS RF system, is standing at the side of one of the cavities. In 1978 and 1979 another 2 cavities were added and entered service in 1980. These were part of the intensity improvement programme and served well for the new role of the SPS as proton-antiproton collider. See also 7411032, 8011289, 8104138, 8302397.

Local Impact Simulation of SC Wall Structures using Aircraft Engine Projectile

International Nuclear Information System (INIS)

Chung, Chulhun; Lee, Jungwhee; Lee, Hanjoo; Jung, Raeyoung; Hyun, Changhun

2013-01-01

SC wall structure developed for nuclear power plant buildings consists of plain concrete and two steel plates on both surface of the concrete, while RC structure consists of re bar and concrete. SC structure has higher scabbing resistance than RC structure due to the action of steel plate on the rear side of impact. Therefore SC structure is known as more effective structure from the viewpoint of aircraft crash than RC structure. However, most of the recent researches and experiments about local impact damage deal with RC structures, and the effect of re bar and steel plate is not considered reasonably. Although Walter et al. and Make-work et al. suggested a formula for evaluating perforation depth of steel plate covered RC walls, most of the previous researches about SC structure are focused on perforation and scabbing due to the impact of hard projectile, rather than soft projectile such as an aircraft. In this research a soft projectile, i. e. aircraft engine, is utilized for impact simulation of RC and SC walls. To evaluate local damage of SC wall structures, parametric study with the variables of wall thickness and steel ratio of the cover plate is performed, and the results are compared with those of RC structures. Since scabbing was prevented by the steel plates, penetration mode of damage was observed in SC walls while scabbing damage was occurred in RC walls. It is confirmed that the rear steel plate not only contains concrete debris, but also reduces the internal damage of the concrete walls. Penetration depth of SC walls did not largely vary due to the increasing steel ratio, and similar results to RC walls were observed when the wall thickness is larger than a certain value since the impact resistance of SC wall is mainly governed by the thickness of concrete part. Therefore, it is expected that similar level of impact resistance to RC structure can be produced with the minimum thickness of steel plates of SC structure. According to these results, SC

Radiolabeling of DOTATOC with the long-lived positron emitter {sup 44}Sc

Energy Technology Data Exchange (ETDEWEB)

Pruszynski, Marek; Majkowska-Pilip, Agnieszka [Centre of Radiochemistry and Nuclear Chemistry, Institute of Nuclear Chemistry and Technology, Dorodna 16, 03-195 Warszawa (Poland); Loktionova, Natalia S.; Eppard, Elisabeth [Institute of Nuclear Chemistry, Johannes Gutenberg-University of Mainz, Fritz-Strassmann-Weg 2, D-55128 Mainz (Germany); Roesch, Frank, E-mail: frank.roesch@uni-mainz.de [Institute of Nuclear Chemistry, Johannes Gutenberg-University of Mainz, Fritz-Strassmann-Weg 2, D-55128 Mainz (Germany)

2012-06-15

The positron-emitting radionuclide {sup 44}Sc with a half-life of 3.97 h and a {beta}{sup +} branching of 94.3% is of potential interest for clinical PET. As so far it is available from a {sup 44}Ti/{sup 44}Sc generator in Mainz, where long-lived {sup 44}Ti decays to no-carrier-added (nca) {sup 44}Sc. The {sup 44}Sc is a trivalent metal cation and should be suitable for complexation with many well established bifunctional chelators conjugated to peptides or other molecular targeting vectors. Thus, the aim of this work was to investigate the potential of {sup 44}Sc for labeling of DOTA-conjugated peptides. DOTA-D-Phe{sup 1}-Tyr{sup 3}-octreotide (DOTATOC) was used as a model molecule to study and optimize labeling procedure. Reaction parameters such as buffer conditions, concentration of peptide, pH range, reaction temperature and time were optimized. Addition of 21 nmol of DOTATOC to {sup 44}Sc in ammonium acetate buffer pH 4.0 provided labeling yields >98% within 25 min of heating in an oil-bath at 95 Degree-Sign C. This time can be reduced to 3 min only by applying microwave supported heating. {sup 44}Sc-DOTATOC was found to be stable in 0.9% NaCl, PBS pH 7.4, fetal calf and human serums, and also in the presence of competing metal cations (Fe{sup 3+}, Ca{sup 2+}, Cu{sup 2+}, Mg{sup 2+}), as well as other ligand competitors, like EDTA and DTPA, even after almost 25 h incubation at 37 Degree-Sign C. Present study shows that nca {sup 44}Sc forms stable complexes with the macrocyclic ligand DOTA and that {sup 44}Sc-DOTATOC and analog targeting vectors may be synthesized for further preclinical and clinical investigations. - Highlights: Black-Right-Pointing-Pointer Labeling of somatostatin analouges with positron emitter {sup 44}Sc was tested. Black-Right-Pointing-Pointer DOTATOC was labeled with {sup 44}Sc isotope. Black-Right-Pointing-Pointer Optimal conditions for {sup 44}Sc-DOTATOC synthesis were found. Black-Right-Pointing-Pointer Stability of {sup 44}Sc

Effect of finite cavity width on flow oscillation in a low-Mach-number cavity flow

Energy Technology Data Exchange (ETDEWEB)

Zhang, Ke; Naguib, Ahmed M. [Michigan State University, East Lansing, MI (United States)

2011-11-15

The current study is focused on examining the effect of the cavity width and side walls on the self-sustained oscillation in a low Mach number cavity flow with a turbulent boundary layer at separation. An axisymmetric cavity geometry is employed in order to provide a reference condition that is free from any side-wall influence, which is not possible to obtain with a rectangular cavity. The cavity could then be partially filled to form finite-width geometry. The unsteady surface pressure is measured using microphone arrays that are deployed on the cavity floor along the streamwise direction and on the downstream wall along the azimuthal direction. In addition, velocity measurements using two-component Laser Doppler Anemometer are performed simultaneously with the array measurements in different azimuthal planes. The compiled data sets are used to investigate the evolution of the coherent structures generating the pressure oscillation in the cavity using linear stochastic estimation of the velocity field based on the wall-pressure signature on the cavity end wall. The results lead to the discovery of pronounced harmonic pressure oscillations near the cavity's side walls. These oscillations, which are absent in the axisymmetric cavity, are linked to the establishment of a secondary mean streamwise circulating flow pattern near the side walls and the interaction of this secondary flow with the shear layer above the cavity. (orig.)

The LHC superconducting cavities

CERN Document Server

Boussard, Daniel; Häbel, E; Kindermann, H P; Losito, R; Marque, S; Rödel, V; Stirbet, M

1999-01-01

The LHC RF system, which must handle high intensity (0.5 A d.c.) beams, makes use of superconducting single-cell cavities, best suited to minimizing the effects of periodic transient beam loading. There will be eight cavities per beam, each capable of delivering 2 MV (5 MV/m accelerating field) at 400 MHz. The cavities themselves are now being manufactured by industry, using niobium-on-copper technology which gives full satisfaction at LEP. A cavity unit includes a helium tank (4.5 K operating temperature) built around a cavity cell, RF and HOM couplers and a mechanical tuner, all housed in a modular cryostat. Four-unit modules are ultimately foreseen for the LHC (two per beam), while at present a prototype version with two complete units is being extensively tested. In addition to a detailed description of the cavity and its ancillary equipment, the first test results of the prototype will be reported.

Portable broadband cavity-enhanced spectrometer utilizing Kalman filtering: application to real-time, in situ monitoring of glyoxal and nitrogen dioxide.

Science.gov (United States)

Fang, Bo; Zhao, Weixiong; Xu, Xuezhe; Zhou, Jiacheng; Ma, Xiao; Wang, Shuo; Zhang, Weijun; Venables, Dean S; Chen, Weidong

2017-10-30

This article describes the development and field application of a portable broadband cavity enhanced spectrometer (BBCES) operating in the spectral range of 440-480 nm for sensitive, real-time, in situ measurement of ambient glyoxal (CHOCHO) and nitrogen dioxide (NO 2 ). The instrument utilized a custom cage system in which the same SMA collimators were used in the transmitter and receiver units for coupling the LED light into the cavity and collecting the light transmitted through the cavity. This configuration realised a compact and stable optical system that could be easily aligned. The dimensions and mass of the optical layer were 676 × 74 × 86 mm 3 and 4.5 kg, respectively. The cavity base length was about 42 cm. The mirror reflectivity at λ = 460 nm was determined to be 0.9998, giving an effective absorption pathlength of 2.26 km. The demonstrated measurement precisions (1σ) over 60 s were 28 and 50 pptv for CHOCHO and NO 2 and the respective accuracies were 5% and 4%. By applying a Kalman adaptive filter to the retrieved concentrations, the measurement precisions of CHOCHO and NO 2 were improved to 8 pptv and 40 pptv in 21 s.

MUON DETECTORS: ALIGNMENT

CERN Multimedia

G.Gomez

2010-01-01

Most of the work in muon alignment since December 2009 has focused on the geometry reconstruction from the optical systems and improvements in the internal alignment of the DT chambers. The barrel optical alignment system has progressively evolved from reconstruction of single active planes to super-planes (December 09) to a new, full barrel reconstruction. Initial validation studies comparing this full barrel alignment at 0T with photogrammetry provide promising results. In addition, the method has been applied to CRAFT09 data, and the resulting alignment at 3.8T yields residuals from tracks (extrapolated from the tracker) which look smooth, suggesting a good internal barrel alignment with a small overall offset with respect to the tracker. This is a significant improvement, which should allow the optical system to provide a start-up alignment for 2010. The end-cap optical alignment has made considerable progress in the analysis of transfer line data. The next set of alignment constants for CSCs will there...

Gadolinium scandium germanide, Gd2Sc3Ge4

Directory of Open Access Journals (Sweden)

Sumohan Misra

2009-04-01

Full Text Available Gd2Sc3Ge4 adopts the orthorhombic Pu5Rh4-type structure. The crystal structure contains six sites in the asymmetric unit: two sites are statistically occupied by rare-earth atoms with Gd:Sc ratios of 0.967 (4:0.033 (4 and 0.031 (3:0.969 (3, one site (.m. symmetry is occupied by Sc atoms, and three distinct sites (two of which with .m. symmetry are occupied by Ge atoms. The rare-earth atoms form two-dimensional slabs with Ge atoms occupying the trigonal-prismatic voids.

Cavity-enhanced spectroscopies

CERN Document Server

van Zee, Roger

2003-01-01

""Cavity-Enhanced Spectroscopy"" discusses the use of optical resonators and lasers to make sensitive spectroscopic measurements. This volume is written by the researcchers who pioneered these methods. The book reviews both the theory and practice behind these spectroscopic tools and discusses the scientific discoveries uncovered by these techniques. It begins with a chapter on the use of optical resonators for frequency stabilization of lasers, which is followed by in-depth chapters discussing cavity ring-down spectroscopy, frequency-modulated, cavity-enhanced spectroscopy, intracavity spectr

Hydroforming of elliptical cavities

Science.gov (United States)

Singer, W.; Singer, X.; Jelezov, I.; Kneisel, P.

2015-02-01

Activities of the past several years in developing the technique of forming seamless (weldless) cavity cells by hydroforming are summarized. An overview of the technique developed at DESY for the fabrication of single cells and multicells of the TESLA cavity shape is given and the major rf results are presented. The forming is performed by expanding a seamless tube with internal water pressure while simultaneously swaging it axially. Prior to the expansion the tube is necked at the iris area and at the ends. Tube radii and axial displacements are computer controlled during the forming process in accordance with results of finite element method simulations for necking and expansion using the experimentally obtained strain-stress relationship of tube material. In cooperation with industry different methods of niobium seamless tube production have been explored. The most appropriate and successful method is a combination of spinning or deep drawing with flow forming. Several single-cell niobium cavities of the 1.3 GHz TESLA shape were produced by hydroforming. They reached accelerating gradients Eacc up to 35 MV /m after buffered chemical polishing (BCP) and up to 42 MV /m after electropolishing (EP). More recent work concentrated on fabrication and testing of multicell and nine-cell cavities. Several seamless two- and three-cell units were explored. Accelerating gradients Eacc of 30 - 35 MV /m were measured after BCP and Eacc up to 40 MV /m were reached after EP. Nine-cell niobium cavities combining three three-cell units were completed at the company E. Zanon. These cavities reached accelerating gradients of Eacc=30 - 35 MV /m . One cavity is successfully integrated in an XFEL cryomodule and is used in the operation of the FLASH linear accelerator at DESY. Additionally the fabrication of bimetallic single-cell and multicell NbCu cavities by hydroforming was successfully developed. Several NbCu clad single-cell and double-cell cavities of the TESLA shape have been

Cavity Processing and Preparation of 650 MHz Elliptical Cell Cavities for PIP-II

Energy Technology Data Exchange (ETDEWEB)

Rowe, Allan [Fermilab; Chandrasekaran, Saravan Kumar [Fermilab; Grassellino, Anna [Fermilab; Melnychuk, Oleksandr [Fermilab; Merio, Margherita [Fermilab; Reid, Thomas [Argonne (main); Sergatskov, Dmitri [Fermilab

2017-05-01

The PIP-II project at Fermilab requires fifteen 650 MHz SRF cryomodules as part of the 800 MeV LINAC that will provide a high intensity proton beam to the Fermilab neutrino program. A total of fifty-seven high-performance SRF cavities will populate the cryomodules and will operate in both pulsed and continuous wave modes. These cavities will be processed and prepared for performance testing utilizing adapted cavity processing infrastructure already in place at Fermilab and Argonne. The processing recipes implemented for these structures will incorporate state-of-the art processing and cleaning techniques developed for 1.3 GHz SRF cavities for the ILC, XFEL, and LCLS-II projects. This paper describes the details of the processing recipes and associated chemistry, heat treatment, and cleanroom processes at the Fermilab and Argonne cavity processing facilities. This paper also presents single and multi-cell cavity test results with quality factors above 5·10¹⁰ and accelerating gradients above 30 MV/m.

Monitor of SC beam profiles

CERN Document Server

CERN PhotoLab

1977-01-01

A high-resolution secondary emission grid for the measurement of SC beam profiles. Modern techniques of metal-ceramic bonding, developed for micro-electronics, have been used in its construction. (See Annual Report 1977 p. 105 Fig. 12.)

Performance Analysis of OFDM 60GHz System and SC-FDE 60GHz System

Directory of Open Access Journals (Sweden)

Han Xueyan

2016-01-01

Full Text Available In this paper, the performance of 60GHz wireless communication system with SC and OFDM is studied, the models of OFDM 60GHz system and SC 60GHz frequency domain equalization (SC-FDE system are established, and the bit error rate (BER performance of OFDM 60GHz system and SC-FDE 60GHz system in 802.15.3c channels is compared. The simulation results show that SC-FDE 60GHz system has a slight advantage over OFDM system in line-of-sight (LOS channels, while OFDM 60GHz system has a slight advantage over SC-FDE system in non-line-of-sight (NLOS channels. For 60GHz system, OFDM 60GHz system has a slight advantage over SC-FDE system in overcoming multipath fading, but the performance of both is close whether in the LOS or NLOS case.

Gallium-containing Heusler phases ScRh{sub 2}Ga, ScPd{sub 2}Ga, TmRh{sub 2}Ga and LuRh{sub 2}Ga. Magnetic and solid state NMR-spectroscopic characterization

Energy Technology Data Exchange (ETDEWEB)

Heletta, Lukas; Seidel, Stefan; Poettgen, Rainer [Muenster Univ. (Germany). Inst. fuer Anorganische und Analytische Chemie; Benndorf, Christopher [Leipzig Univ. (Germany). Inst. fuer Mineralogie, Kristallographie und Materialwissenschaften; Eckert, Hellmut [Muenster Univ. (Germany). Inst. fuer Physikalische Chemie; Sao Paulo Univ., Sao Carlos (Brazil). Inst. of Physics

2017-10-01

The gallium-containing Heusler phases ScRh{sub 2}Ga, ScPd{sub 2}Ga, TmRh{sub 2}Ga and LuRh{sub 2}Ga have been synthesized by arc-melting of the elements followed by different annealing sequences to improve phase purity. The samples have been studied by powder X-ray diffraction. The structures of Lu{sub 0.97}Rh{sub 2}Ga{sub 1.03} (Fm3m, a=632.94(5) pm, wR2=0.0590, 46 F{sup 2} values, seven variables) and Sc{sub 0.88}Rh{sub 2}Ga{sub 1.12} (a=618.91(4) pm, wR2=0.0284, 44 F{sup 2} values, six variables) have been refined from single crystal X-ray diffractometer data. Both gallides show structural disorder through Lu/Ga and Sc/Ga mixing. Temperature dependent magnetic susceptibility measurements showed Pauli paramagnetism for ScRh{sub 2}Ga, ScPd{sub 2}Ga, and LuRh{sub 2}Ga and Curie-Weiss paramagnetism for TmRh{sub 2}Ga. {sup 45}Sc and {sup 71}Ga solid state MAS NMR spectroscopic investigations of the Sc containing compounds confirmed the site mixing effects typically observed for Heusler phases. The data indicate that the effect of mixed Sc/Ga occupancy is significantly stronger in ScRh{sub 2}Ga than in ScPd{sub 2}Ga.

Formation of coronal cavities

International Nuclear Information System (INIS)

An, C.H.; Suess, S.T.; Tandberg-Hanssen, E.; Steinolfson, R.S.

1986-01-01

A theoretical study of the formation of a coronal cavity and its relation to a quiescent prominence is presented. It is argued that the formation of a cavity is initiated by the condensation of plasma which is trapped by the coronal magnetic field in a closed streamer and which then flows down to the chromosphere along the field lines due to lack of stable magnetic support against gravity. The existence of a coronal cavity depends on the coronal magnetic field strength; with low strength, the plasma density is not high enough for condensation to occur. Furthermore, we suggest that prominence and cavity material is supplied from the chromospheric level. Whether a coronal cavity and a prominence coexist depends on the magnetic field configuration; a prominence requires stable magnetic support

PEMODELAN KONDUKTIVITAS ION DALAM STRUKTUR Li2Sc3(PO43 (Modeling Ionic Conductivity in Li2Sc3(PO43 Structure

Directory of Open Access Journals (Sweden)

Akram La Kilo

2011-11-01

Full Text Available ABSTRAK Fasa Li2Sc3(PO43 merupakan material konduktor superionik yang dapat diaplikasikan sebagai baterai yang dapat diisi ulang (rechargeable. Ion Li+ dalam struktur Li2Sc3(PO4 dapat mengalami migrasi dari posisi terisi ke posisi kosong. Penelitian ini telah memodelkan migrasi ion Li+ dalam struktur Li2Sc3(PO4 dengan menggunakan metode bond valence sum (BVS. Metode ini dapat memprediksi bilangan oksidasi suatu atom berdasarkan jarak dengan atom-atom tetangga. Source code berbasis BVS yang digunakan adalah JUMPITER yang mensimulasi efek gaya listrik eksternal yang bertindak pada ion litium sehingga nilai BVS litium dapat dipetakan terhadap jarak. Hasil simulasi menunjukkan bahwa konduksi ion Li+ dapat terjadi pada arah [010], [101], dan [120]. Namun, lintasan konduksi ion Li+ lebih mudah terjadi pada arah [120] atau bidang ab dengan nilai maksimum BVS adalah 0,982. ABSTRACT g-phase of Li2Sc3(PO43 is a lithium super ionic conductor which can be applied as a rechargeable lithium battery. Lithium ions of g-Li2Sc3(PO43 can migrate from occupied site to vacant site. In this research, simulation of Li+ ions migration in the structure of g-Li2Sc3(PO43 carried out using bond valence sum (BVS to predict the oxidation state of Li+ion based on the distance of the ion to neighboring atoms. BVS-based code used JUMPITER to simulate the effect of external electrical force acting on the lithium ions to produce the lithium BVS value which can be mapped to the distance. The simulation results shows that Li+ ion conduction can be occurred on [010], [101], and [120] directions. However, the Li ion conduction pathway occur more easily in the direction of [120] or ab plane with the BVS maximum value is 0.982.

File list: Unc.PSC.50.AllAg.EpiSC [Chip-atlas[Archive

Lifescience Database Archive (English)

Full Text Available Unc.PSC.50.AllAg.EpiSC mm9 Unclassified Pluripotent stem cell EpiSC SRX1074917,SRX1...074905,SRX1074908 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Unc.PSC.50.AllAg.EpiSC.bed ...

File list: Unc.PSC.05.AllAg.EpiSC [Chip-atlas[Archive

Lifescience Database Archive (English)

Full Text Available Unc.PSC.05.AllAg.EpiSC mm9 Unclassified Pluripotent stem cell EpiSC SRX1074917,SRX1...074908,SRX1074905 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Unc.PSC.05.AllAg.EpiSC.bed ...

File list: Unc.PSC.20.AllAg.EpiSC [Chip-atlas[Archive

Lifescience Database Archive (English)

Full Text Available Unc.PSC.20.AllAg.EpiSC mm9 Unclassified Pluripotent stem cell EpiSC SRX1074917,SRX1...074908,SRX1074905 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Unc.PSC.20.AllAg.EpiSC.bed ...

The Superconducting TESLA Cavities

CERN Document Server

Aune, B.; Bloess, D.; Bonin, B.; Bosotti, A.; Champion, M.; Crawford, C.; Deppe, G.; Dwersteg, B.; Edwards, D.A.; Edwards, H.T.; Ferrario, M.; Fouaidy, M.; Gall, P-D.; Gamp, A.; Gössel, A.; Graber, J.; Hubert, D.; Hüning, M.; Juillard, M.; Junquera, T.; Kaiser, H.; Kreps, G.; Kuchnir, M.; Lange, R.; Leenen, M.; Liepe, M.; Lilje, L.; Matheisen, A.; Möller, W-D.; Mosnier, A.; Padamsee, H.; Pagani, C.; Pekeler, M.; Peters, H-B.; Peters, O.; Proch, D.; Rehlich, K.; Reschke, D.; Safa, H.; Schilcher, T.; Schmüser, P.; Sekutowicz, J.; Simrock, S.; Singer, W.; Tigner, M.; Trines, D.; Twarowski, K.; Weichert, G.; Weisend, J.; Wojtkiewicz, J.; Wolff, S.; Zapfe, K.

2000-01-01

The conceptional design of the proposed linear electron-positron colliderTESLA is based on 9-cell 1.3 GHz superconducting niobium cavities with anaccelerating gradient of Eacc >= 25 MV/m at a quality factor Q0 > 5E+9. Thedesign goal for the cavities of the TESLA Test Facility (TTF) linac was set tothe more moderate value of Eacc >= 15 MV/m. In a first series of 27industrially produced TTF cavities the average gradient at Q0 = 5E+9 wasmeasured to be 20.1 +- 6.2 MV/m, excluding a few cavities suffering fromserious fabrication or material defects. In the second production of 24 TTFcavities additional quality control measures were introduced, in particular aneddy-current scan to eliminate niobium sheets with foreign material inclusionsand stringent prescriptions for carrying out the electron-beam welds. Theaverage gradient of these cavities at Q0 = 5E+9 amounts to 25.0 +- 3.2 MV/mwith the exception of one cavity suffering from a weld defect. Hence only amoderate improvement in production and preparation technique...

Sensing Characteristics of A Precision Aligner Using Moire Gratings for Precision Alignment System

Institute of Scientific and Technical Information of China (English)

ZHOU Lizhong; Hideo Furuhashi; Yoshiyuki Uchida

2001-01-01

Sensing characteristics of a precision aligner using moire gratings for precision alignment sysem has been investigated. A differential moire alignment system and a modified alignment system were used. The influence of the setting accuracy of the gap length and inclination of gratings on the alignment accuracy has been studied experimentally and theoretically. Setting accuracy of the gap length less than 2.5μm is required in modified moire alignment. There is no influence of the gap length on the alignment accuracy in the differential alignment system. The inclination affects alignment accuracies in both differential and modified moire alignment systems.

MUON DETECTORS: ALIGNMENT

CERN Multimedia

Z. Szillasi and G. Gomez.

2013-01-01

When CMS is opened up, major components of the Link and Barrel Alignment systems will be removed. This operation, besides allowing for maintenance of the detector underneath, is needed for making interventions that will reinforce the alignment measurements and make the operation of the alignment system more reliable. For that purpose and also for their general maintenance and recalibration, the alignment components will be transferred to the Alignment Lab situated in the ISR area. For the track-based alignment, attention is focused on the determination of systematic uncertainties, which have become dominant, since now there is a large statistics of muon tracks. This will allow for an improved Monte Carlo misalignment scenario and updated alignment position errors, crucial for high-momentum muon analysis such as Z′ searches.

Triangular Alignment (TAME). A Tensor-based Approach for Higher-order Network Alignment

Energy Technology Data Exchange (ETDEWEB)

Mohammadi, Shahin [Purdue Univ., West Lafayette, IN (United States); Gleich, David F. [Purdue Univ., West Lafayette, IN (United States); Kolda, Tamara G. [Sandia National Laboratories (SNL-CA), Livermore, CA (United States); Grama, Ananth [Purdue Univ., West Lafayette, IN (United States)

2015-11-01

Network alignment is an important tool with extensive applications in comparative interactomics. Traditional approaches aim to simultaneously maximize the number of conserved edges and the underlying similarity of aligned entities. We propose a novel formulation of the network alignment problem that extends topological similarity to higher-order structures and provide a new objective function that maximizes the number of aligned substructures. This objective function corresponds to an integer programming problem, which is NP-hard. Consequently, we approximate this objective function as a surrogate function whose maximization results in a tensor eigenvalue problem. Based on this formulation, we present an algorithm called Triangular AlignMEnt (TAME), which attempts to maximize the number of aligned triangles across networks. We focus on alignment of triangles because of their enrichment in complex networks; however, our formulation and resulting algorithms can be applied to general motifs. Using a case study on the NAPABench dataset, we show that TAME is capable of producing alignments with up to 99% accuracy in terms of aligned nodes. We further evaluate our method by aligning yeast and human interactomes. Our results indicate that TAME outperforms the state-of-art alignment methods both in terms of biological and topological quality of the alignments.

Phase relationship in AL-Cu-Sc alloys at 450-500 deg C

International Nuclear Information System (INIS)

Kharakterova, M.L.

1991-01-01

Al-Cu-Sc alloys containing up to 40% Cu and up to 6% Sc at 450 deg C and 500 deg C are studied using light microscopy, X-ray-spectral microanalysis, X-ray diffraction analysis, scanning electron microscopy, measurement of microhardness and electric resistance. It is determined, that in equilibrium with aluminium solid solution under the given temperature ther are Al 3 Sc, CuAl 2 phases of the respective binary systems and W (ScCu 6.6-4 Al 5.4-8 ) ternary phase. Isothermal cross sections of Al-Cu-Sc system at 450 and 500 deg C are plotted. Microhardness of equilibrium phases is measured. Combined solubility of copper and scandium in aluminium is determined

Effect of Sc addition on microstructure and mechanical properties of 1460 alloy

Directory of Open Access Journals (Sweden)

Juan Ma

2014-02-01

Full Text Available The effect of minor addition of Sc on microstructure, age hardening behavior, tensile properties and fracture morphology of 1460 alloy have been studied. It is found that Sc content increase from 0.11 wt% to 0.22 wt% is favorable for grain refinement in as-cast alloy but results in a coarsening of Cu-rich particles. The alloy with 0.11 wt% Sc exhibits enhanced mechanical properties and age hardening effect. Transmission electron microscopy (TEM investigations on the alloy with 0.11 wt% Sc have suggested that a large amount of Al3(Sc, Zr particles precipitated at the earlier aging may inhibit recrystallization effectively.

A high gradient test of a single-cell superconducting radio frequency cavity with a feedback waveguide

Science.gov (United States)

Kostin, Roman; Avrakhov, Pavel; Kanareykin, Alexei; Solyak, Nikolay; Yakovlev, Vyacheslav; Kazakov, Sergey; Wu, Genfa; Khabiboulline, Timergali; Rowe, Allan; Rathke, John

2015-09-01

The most severe problem of the international linear collider (ILC-type) is its high cost, resulting in part from the enormous length of the collider. This length is determined mainly by the achievable accelerating gradient in the RF system of the collider. In current technology, the maximum acceleration gradient in superconducting (SC) structures is determined mainly by the value of the surface RF magnetic field. In order to increase the gradient, a superconducting traveling wave accelerating (STWA) structure is suggested. Utilization of STWA structure with small phase advance per cell for future high energy linear colliders such as ILCs may provide an accelerating gradient 1.2-1.4 times larger [1] than a standing wave structure. However, STWA structure requires a feedback waveguide for power redirecting from the end of the structure back to the front end of accelerating structure. Recent tests of a 1.3 GHz model of a single-cell cavity with waveguide feedback demonstrated an accelerating gradient comparable to the gradient of a single-cell ILC-type cavity from the same manufacturer [2]. In the present paper, high gradient test results are presented.

MUON DETECTORS: ALIGNMENT

CERN Multimedia

G. Gomez and J. Pivarski

2011-01-01

Alignment efforts in the first few months of 2011 have shifted away from providing alignment constants (now a well established procedure) and focussed on some critical remaining issues. The single most important task left was to understand the systematic differences observed between the track-based (TB) and hardware-based (HW) barrel alignments: a systematic difference in r-φ and in z, which grew as a function of z, and which amounted to ~4-5 mm differences going from one end of the barrel to the other. This difference is now understood to be caused by the tracker alignment. The systematic differences disappear when the track-based barrel alignment is performed using the new “twist-free” tracker alignment. This removes the largest remaining source of systematic uncertainty. Since the barrel alignment is based on hardware, it does not suffer from the tracker twist. However, untwisting the tracker causes endcap disks (which are aligned ...

MUON DETECTORS: ALIGNMENT

CERN Multimedia

Gervasio Gomez

The main progress of the muon alignment group since March has been in the refinement of both the track-based alignment for the DTs and the hardware-based alignment for the CSCs. For DT track-based alignment, there has been significant improvement in the internal alignment of the superlayers inside the DTs. In particular, the distance between superlayers is now corrected, eliminating the residual dependence on track impact angles, and good agreement is found between survey and track-based corrections. The new internal geometry has been approved to be included in the forthcoming reprocessing of CRAFT samples. The alignment of DTs with respect to the tracker using global tracks has also improved significantly, since the algorithms use the latest B-field mapping, better run selection criteria, optimized momentum cuts, and an alignment is now obtained for all six degrees of freedom (three spatial coordinates and three rotations) of the aligned DTs. This work is ongoing and at a stage where we are trying to unders...

Hydroforming of elliptical cavities

Directory of Open Access Journals (Sweden)

W. Singer

2015-02-01

Full Text Available Activities of the past several years in developing the technique of forming seamless (weldless cavity cells by hydroforming are summarized. An overview of the technique developed at DESY for the fabrication of single cells and multicells of the TESLA cavity shape is given and the major rf results are presented. The forming is performed by expanding a seamless tube with internal water pressure while simultaneously swaging it axially. Prior to the expansion the tube is necked at the iris area and at the ends. Tube radii and axial displacements are computer controlled during the forming process in accordance with results of finite element method simulations for necking and expansion using the experimentally obtained strain-stress relationship of tube material. In cooperation with industry different methods of niobium seamless tube production have been explored. The most appropriate and successful method is a combination of spinning or deep drawing with flow forming. Several single-cell niobium cavities of the 1.3 GHz TESLA shape were produced by hydroforming. They reached accelerating gradients E_{acc} up to 35  MV/m after buffered chemical polishing (BCP and up to 42  MV/m after electropolishing (EP. More recent work concentrated on fabrication and testing of multicell and nine-cell cavities. Several seamless two- and three-cell units were explored. Accelerating gradients E_{acc} of 30–35  MV/m were measured after BCP and E_{acc} up to 40  MV/m were reached after EP. Nine-cell niobium cavities combining three three-cell units were completed at the company E. Zanon. These cavities reached accelerating gradients of E_{acc}=30–35  MV/m. One cavity is successfully integrated in an XFEL cryomodule and is used in the operation of the FLASH linear accelerator at DESY. Additionally the fabrication of bimetallic single-cell and multicell NbCu cavities by hydroforming was successfully developed. Several NbCu clad single-cell and

Mathematical models of some geomagnetic storms with SC

International Nuclear Information System (INIS)

Ivanova, P.K.

1990-01-01

Regressive equations for H horizontal component of three geomagnetic storms with Sc:0.1.03.82, 24.01.74 and 23.03.69 -are calculated using step-by-step regression analysis. These equations relate H with parameters of solar wind and interplanetary magnetic field. Nonlinear, square, logarithmic and trigonometric dependences are considered, as well. Most essential parameters, which contribute mostly into Sc, are determined from multiplicity (46 factors) of independent parameters

Radiation protection Group (SC/RP) desperately seeking...

CERN Document Server

A. Hervé, Y. Donjoux / SC

2006-01-01

We are trying to trace two transit permits (passavants), which constitute the customs clearance documentation for two 'AD6'portable radiation detectors. The two permits (No. 1308 and No. 1309) were sent in the same internal mail envelope towards the middle of March 2006 but never reached their final destination. After weeks of searching in vain, we are now appealing for your help. If you have these two permits in your possession, please get in touch with us. Many thanks in advance. A.HERVE - SC/RP- ( 163168 / 70927) Y.DONJOUX - SC/RP - (160105 / 73171)

[Roberts-SC phocomelia syndrome].

Science.gov (United States)

Musfeld, D A; Bühler, E M; Heinzl, S

2001-01-01

The Roberts-SC phocomelia syndrome is a rare autosomal recessive inherited disorder clinically manifested by tetraphocomelia, pre- and postnatal growth retardation, and craniofacial abnormalities (skull, eyes, lip, and palate), accompanied at times by centromer puffing and splitting, renal abnormalities, heart defect, clitoral or penile enlargement, and bilateral corneal opacities. Mental retardation is common in surviving patients.

Model of Dees and Rotco for the 600 MeV SC

CERN Multimedia

CERN PhotoLab

1978-01-01

The accelerating frequency of the 600 MeV Synchro-Cyclotron (SC) was modulated by the varying capacity of a rotating condenser ("Rotco", the most delicate component of the SC). A 1/5-scale model, dating from the design-period of the SC, was used to study improvements to the SC RF-system, and also the acceleration of ions, first Helium and, at the time of this picture, Carbon. In the middle of the picture is the case containing the Dees. To the left, at the wide end of the cone, a rotco. Reinhold Hohbach is busy with measurements. See also 7805235 (Annual Report 1978, p.110).

Millimeter wave surface resistance of grain-aligned Y1Ba2Cu3O(x) bulk material

International Nuclear Information System (INIS)

Wosik, J.; Kranenburg, R.A.; Wolfe, J.C.; Selvamanickam, V.; Salama, K.

1990-04-01

Measurements are reported of the millimeter-wave surface resistance of grain-aligned YBa2Cu3O(x) bulk material grown by a liquid-phase process. The measurements were performed by replacing the endplate of a TE(011) cylindrical copper cavity with the superconducting sample. Surface resistance was measured for samples with surfaces oriented perpendicular and parallel to the c-axis of the grains. For the parallel configuration, the surface resistance at 77 K and 80 GHz is given. For a very well-aligned sample with a very low density of Y2BaCuO(y) precipitates, measured in the perpendicular configuration, the transition width (10-90 percent) is about 2 K and the surface resistance is derived at 88 K. The effect of microstructure on surface resistance is discussed. 19 refs

First coil for the SC

CERN Multimedia

CERN PhotoLab

1955-01-01

The coils for the SC magnet were stored in the large hangar of the Cointrin Airport (to make sure that they would be available before snow and ice would block the roads and canals from Belgium, where they were built).

Some peculiarities of ScFe2 and ScNi2 interaction with ammonia in the presence of NH4Cl

International Nuclear Information System (INIS)

Shilkin, S.P.; Fokin, V.N.; Fokina, Eh.Eh.; Tarasov, B.P.; Korobkov, I.I.

2000-01-01

Interaction of ScFe 2 and ScNi 2 intermetallic compounds with ammonia in the presence of NH 4 Cl (10 mass % from intermetallide introduced in reaction) as an activator of the process in initial ammonia pressure 0.6-0.8 MPa is investigated. Possibility of preparation of crystalline intermetallide hydrides and amorphous products in highly dispersed state at different temperature are shown. It is established that intermetallides decompose in ammonia medium at ≥ 450 Deg C [ru

Theoretical study of stability and superconductivity of ScHn (n =4 -8 ) at high pressure

Science.gov (United States)

Qian, Shifeng; Sheng, Xiaowei; Yan, Xiaozhen; Chen, Yangmei; Song, Bo

2017-09-01

The synthesis of hydrogen sulfides, with the potential of high-temperature superconductivity, was recently proposed at high Tc = 203 K. It motivated us to employ an ab initio approach for the predictions of crystal structures to find the stable scandium hydrides. In addition to the earlier predicted three stoichiometries of ScH, ScH2, and ScH3, we identify three other metallic stoichiometries of ScH4, ScH6, and ScH8, which show superconductivity at significantly higher temperatures. The phases of ScH4 and ScH6, whose stability does not require extremely high pressures (ZPE), are primarily ionic compounds containing exotic quasimolecular H2 arrangements. The present electron-phonon calculations revealed the superconductive potential of ScH4 and ScH6 with estimated Tc of 98 K and 129 K at 200 GPa and 130 GPa, respectively. The superconductivity of ScHn stems from the large electron-phonon coupling associated with the wagging, bending, and intermediate-frequency modes attributed mainly to the hydrogen atoms.

Methods for production of UNK SC-dipoles magnetic measurements

International Nuclear Information System (INIS)

Smirnov, N.L.

1991-01-01

Many SC-dipoles for UNK will require from the chosen magnetic measurement methods high accuracy and efficiency. The brief of using methods, their possibilities and analysis of their errors are given. The measurements results for a full-scale model of SC-dipole SPDM1 are presented. 5 refs.; 4 figs.; 4 tabs

Study of the hyperfine magnetic field at Ta181 site in the Heusler Co2 Sc Sn, Co2 Sc Ga and Co2 Hf Sn alloys

International Nuclear Information System (INIS)

Attili, R.N.

1992-01-01

The hyperfine magnetic fields acting on 181 Ta nuclei at the Sc and Hf sites have been measured in Heusler alloys Co 2 Sc Sn and Co 2 Sc Ga and Co 2 Hf Sn using the Time Differential Perturbed γ-γ Angular Correlation (TDPAC) technique. The measurements were carried out using an automatic spectrometer consisting of two Ba F 2 detectors and the conventional electronics. The magnitude of hyperfine magnetic field at 181 Ta was measured for all the alloys. The signs of the were determined in the cases of Co 2 Sc Sn and Co 2 Hf Sn alloys by performing the Perturbed Angular Correlation measurements with an external polarizing magnetic field of ≅ 5 k Gauss. The hyperfine magnetic fields obtained are -187,6± 3,3 and 90,0 ± 2,1 kOe measured at 77 K for Co 2 Sc Sn and Co 2 Sc Ga alloys respectively, and -342,4 ± 10,1 kOe measured at the room temperature for Co 2 Hf Sn alloy. These results are discussed and compared with the hyperfine magnetic field systematics in Co-based Heusler alloy. (author)

Level densities and γ strength functions in light Sc and Ti isotopes

International Nuclear Information System (INIS)

Burger, A.; Larsen, A.C.; Syed, N.U.H.; Guttormsen, M.; Nyhus, H.; Siem, S.; Harissopulos, S.; Konstantinopoulos, T.; Lagoyannis, A.; Perdidakis, G.; Spyrou, A.; Kmiecik, M.; Mazurek, K.; Krticka, M.; Loennroth, T.; Norby, M.; Voinov, A.

2010-01-01

We present preliminary results from a measurement of nuclear level densities and the γ-ray strength of light Sc (Sc 43 , Sc 45 ) and Ti (Ti 44 , Ti 45 and Ti 46 ) isotopes using the Oslo Method. The article begins with a presentation of the experimental setup. (authors)

Millimeter wave surface resistance of grain-aligned Y1Ba2Cu3Ox bulk material

International Nuclear Information System (INIS)

Wosik, J.; Kranenburg, R.A.; Wolfe, J.C.; Selvamanickam, V.; Salama, K.

1991-01-01

We report measurements of the millimeter wave surface resistance of grain-aligned YBa 2 Cu 3 O x bulk material grown by a liquid phase process. The measurements were performed by replacing the endplate of a TE 011 cylindrical copper cavity with the superconducting sample. Surface resistance was measured for samples with surfaces oriented perpendicular and parallel to the c-axis of the grains. We show that, for the parallel configuration, the surface resistance at 77 K and 80 GHz is typically near 100 mΩ. For a very well-aligned sample with a very low density of Y 2 BaCuO y precipitates, measured in the perpendicular configuration, the transition width (10%--90%) is about 2 K and the surface resistance is less than 50 mΩ at 88 K. The effect of microstructure on surface resistance is discussed

Tuner Design for PEFP Superconducting RF Cavities

International Nuclear Information System (INIS)

Tang, Yazhe; An, Sun; Zhang, Liping; Cho, Yong Sub

2009-01-01

A superconducting radio frequency (SRF) cavity will be used to accelerate a proton beam after 100 MeV at 700 MHz in a linac of the Proton Engineering Frontier Project (PEFP) and its extended project. In order to control the SRF cavity's operating frequency at a low temperature, a new tuner has been developed for the PEFP SRF cavities. Each PEFP superconducting RF cavity has one tuner to match the cavity resonance frequency with the desired accelerator operating frequency; or to detune a cavity frequency a few bandwidths away from a resonance, so that the beam will not excite the fundamental mode, when the cavity is not being used for an acceleration. The PEFP cavity tuning is achieved by varying the total length of the cavity. The length of the cavity is controlled differentially by tuner acting with respect to the cavity body. The PEFP tuner is attached to the helium vessel and drives the cavity Field Probe (FP) side to change the frequency of the cavity

The data acquisition system (DAS) for the improved CERN SC

CERN Document Server

Beger, H; Fiebig, A; Schroot, H

1975-01-01

A digital data acquisition system (DAS) based on a minicomputer is described which registers the failure sequences in various equipment areas of the CERN synchrocyclotron (henceforward referred to as the SC). The avalanches of failure signals which occur from time to time are tapped from the alarm/security systems, time-resolved to 10 msec and recorded on a printer in order to aid SC failure diagnosis. The mechanisms of the DAS and its relation to the SC equipment are explained in some detail. All programs were constructed at assembler language level for speed and for ease of on-line program maintenance. The alarm sequences recorded have been of considerable help during the running in of the new radiofrequency system. Now that the new SC is operational, the DAS furnishes useful data from several equipment areas to the operators and engineers.

Computation of Normal Conducting and Superconducting Linear Accelerator (LINAC) Availabilities

International Nuclear Information System (INIS)

Haire, M.J.

2000-01-01

A brief study was conducted to roughly estimate the availability of a superconducting (SC) linear accelerator (LINAC) as compared to a normal conducting (NC) one. Potentially, SC radio frequency cavities have substantial reserve capability, which allows them to compensate for failed cavities, thus increasing the availability of the overall LINAC. In the initial SC design, there is a klystron and associated equipment (e.g., power supply) for every cavity of an SC LINAC. On the other hand, a single klystron may service eight cavities in the NC LINAC. This study modeled that portion of the Spallation Neutron Source LINAC (between 200 and 1,000 MeV) that is initially proposed for conversion from NC to SC technology. Equipment common to both designs was not evaluated. Tabular fault-tree calculations and computer-event-driven simulation (EDS) computer computations were performed. The estimated gain in availability when using the SC option ranges from 3 to 13% under certain equipment and conditions and spatial separation requirements. The availability of an NC LINAC is estimated to be 83%. Tabular fault-tree calculations and computer EDS modeling gave the same 83% answer to within one-tenth of a percent for the NC case. Tabular fault-tree calculations of the availability of the SC LINAC (where a klystron and associated equipment drive a single cavity) give 97%, whereas EDS computer calculations give 96%, a disagreement of only 1%. This result may be somewhat fortuitous because of limitations of tabular fault-tree calculations. For example, tabular fault-tree calculations can not handle spatial effects (separation distance between failures), equipment network configurations, and some failure combinations. EDS computer modeling of various equipment configurations were examined. When there is a klystron and associated equipment for every cavity and adjacent cavity, failure can be tolerated and the SC availability was estimated to be 96%. SC availability decreased as

MUON DETECTORS: ALIGNMENT

CERN Multimedia

G. Gomez

Since December, the muon alignment community has focused on analyzing the data recorded so far in order to produce new DT and CSC Alignment Records for the second reprocessing of CRAFT data. Two independent algorithms were developed which align the DT chambers using global tracks, thus providing, for the first time, a relative alignment of the barrel with respect to the tracker. These results are an important ingredient for the second CRAFT reprocessing and allow, for example, a more detailed study of any possible mis-modelling of the magnetic field in the muon spectrometer. Both algorithms are constructed in such a way that the resulting alignment constants are not affected, to first order, by any such mis-modelling. The CSC chambers have not yet been included in this global track-based alignment due to a lack of statistics, since only a few cosmics go through the tracker and the CSCs. A strategy exists to align the CSCs using the barrel as a reference until collision tracks become available. Aligning the ...

MUON DETECTORS: ALIGNMENT

CERN Multimedia

G.Gomez

2011-01-01

The Muon Alignment work now focuses on producing a new track-based alignment with higher track statistics, making systematic studies between the results of the hardware and track-based alignment methods and aligning the barrel using standalone muon tracks. Currently, the muon track reconstruction software uses a hardware-based alignment in the barrel (DT) and a track-based alignment in the endcaps (CSC). An important task is to assess the muon momentum resolution that can be achieved using the current muon alignment, especially for highly energetic muons. For this purpose, cosmic ray muons are used, since the rate of high-energy muons from collisions is very low and the event statistics are still limited. Cosmics have the advantage of higher statistics in the pT region above 100 GeV/c, but they have the disadvantage of having a mostly vertical topology, resulting in a very few global endcap muons. Only the barrel alignment has therefore been tested so far. Cosmic muons traversing CMS from top to bottom are s...

Paracyclophane functionalized with Sc and Li for hydrogen storage

Science.gov (United States)

Sathe, Rohit Y.; Dhilip Kumar, T. J.

2018-01-01

Li and Sc metals functionalized on the delocalized π -electrons of benzene rings in [2,2]paracyclophane structure are studied for hydrogen storage efficiency by using the M06 DFT functional with 6-311G(d,p) basis set. It is found that Sc and Li functionalized [2,2]paracyclophane complexes can hold up to 10 H2 molecules and 8 H2 molecules by Kubas-Niu-Jena interaction and charge polarization mechanism with hydrogen weight percentage of 11.4 and 13.5, respectively. Molecular dynamics simulation at various temperatures showed appreciable thermal stability while the chemical potential calculation at room temperature reveals that Sc functionalized [2,2]paracyclophane system will be a promising hydrogen storage material.

LEP copper accelerating cavities

CERN Multimedia

Laurent Guiraud

1999-01-01

These copper cavities were used to generate the radio frequency electric field that was used to accelerate electrons and positrons around the 27-km Large Electron-Positron (LEP) collider at CERN, which ran from 1989 to 2000. The copper cavities were gradually replaced from 1996 with new superconducting cavities allowing the collision energy to rise from 90 GeV to 200 GeV by mid-1999.

Effects of cavity-cavity interaction on the entanglement dynamics of a generalized double Jaynes-Cummings model

Science.gov (United States)

Pandit, Mahasweta; Das, Sreetama; Singha Roy, Sudipto; Shekhar Dhar, Himadri; Sen, Ujjwal

2018-02-01

We consider a generalized double Jaynes-Cummings model consisting of two isolated two-level atoms, each contained in a lossless cavity that interact with each other through a controlled photon-hopping mechanism. We analytically show that at low values of such a mediated cavity-cavity interaction, the temporal evolution of entanglement between the atoms, under the effects of cavity perturbation, exhibits the well-known phenomenon of entanglement sudden death (ESD). Interestingly, for moderately large interaction values, a complete preclusion of ESD is achieved, irrespective of its value in the initial atomic state. Our results provide a model to sustain entanglement between two atomic qubits, under the adverse effect of cavity induced perturbation, by introducing a non-intrusive inter-cavity photon exchange that can be physically realized through cavity-QED setups in contemporary experiments.

Temperature Structure of a Coronal Cavity

Science.gov (United States)

Kucera, T. A.; Gibson, S. E.; Schmit, D. J.

2011-01-01

we analyze the temperature structure of a coronal cavity observed in Aug. 2007. coronal cavities are long, low-density structures located over filament neutral lines and are often seen as dark elliptical features at the solar limb in white light, EUV and x-rays. when these structures erupt they form the cavity portions of CMEs. It is important to establish the temperature structure of cavities in order to understand the thermodynamics of cavities in relation to their three-dimensional magnetic structure. To analyze the temperature we compare temperature ratios of a series of iron lines observed by the Hinode/EUv Imaging spectrometer (EIS). We also use those lines to constrain a forward model of the emission from the cavity and streamer. The model assumes a coronal streamer with a tunnel-like cavity with elliptical cross-section and a Gaussian variation of height along the tunnel lenth. Temperature and density can be varied as a function of altitude both in the cavity and streamer. The general cavity morphology and the cavity and streamer density have already been modeled using data from STEREO's SECCHI/EUVI and Hinode/EIS (Gibson et al 2010 and Schmit & Gibson 2011).

Toward low-cost affinity reagents: lyophilized yeast-scFv probes specific for pathogen antigens.

Directory of Open Access Journals (Sweden)

Sean A Gray

Full Text Available The generation of affinity reagents, usually monoclonal antibodies, remains a critical bottleneck in biomedical research and diagnostic test development. Recombinant antibody-like proteins such as scFv have yet to replace traditional monoclonal antibodies in antigen detection applications, in large part because of poor performance of scFv in solution. To address this limitation, we have developed assays that use whole yeast cells expressing scFv on their surfaces (yeast-scFv in place of soluble purified scFv or traditional monoclonal antibodies. In this study, a nonimmune library of human scFv displayed on the surfaces of yeast cells was screened for clones that bind to recombinant cyst proteins of Entamoeba histolytica, an enteric pathogen of humans. Selected yeast-scFv clones were stabilized by lyophilization and used in detection assay formats in which the yeast-scFv served as solid support-bound monoclonal antibodies. Specific binding of antigen to the yeast-scFv was detected by staining with rabbit polyclonal antibodies. In flow cytometry-based assays, lyophilized yeast-scFv reagents retained full binding activity and specificity for their cognate antigens after 4 weeks of storage at room temperature in the absence of desiccants or stabilizers. Because flow cytometry is not available to all potential assay users, an immunofluorescence assay was also developed that detects antigen with similar sensitivity and specificity. Antigen-specific whole-cell yeast-scFv reagents can be selected from nonimmune libraries in 2-3 weeks, produced in vast quantities, and packaged in lyophilized form for extended shelf life. Lyophilized yeast-scFv show promise as low cost, renewable alternatives to monoclonal antibodies for diagnosis and research.

Assembly and Regulation of the Membrane Attack Complex Based on Structures of C5b6 and sC5b9

Directory of Open Access Journals (Sweden)

Michael A. Hadders

2012-03-01

Full Text Available Activation of the complement system results in formation of membrane attack complexes (MACs, pores that disrupt lipid bilayers and lyse bacteria and other pathogens. Here, we present the crystal structure of the first assembly intermediate, C5b6, together with a cryo-electron microscopy reconstruction of a soluble, regulated form of the pore, sC5b9. Cleavage of C5 to C5b results in marked conformational changes, distinct from those observed in the homologous C3-to-C3b transition. C6 captures this conformation, which is preserved in the larger sC5b9 assembly. Together with antibody labeling, these structures reveal that complement components associate through sideways alignment of the central MAC-perforin (MACPF domains, resulting in a C5b6-C7-C8β-C8α-C9 arc. Soluble regulatory proteins below the arc indicate a potential dual mechanism in protection from pore formation. These results provide a structural framework for understanding MAC pore formation and regulation, processes important for fighting infections and preventing complement-mediated tissue damage.

Normal Conducting RF Cavity for MICE

International Nuclear Information System (INIS)

Li, D.; DeMello, A.; Virostek, S.; Zisman, M.; Summers, D.

2010-01-01

Normal conducting RF cavities must be used for the cooling section of the international Muon Ionization Cooling Experiment (MICE), currently under construction at Rutherford Appleton Laboratory (RAL) in the UK. Eight 201-MHz cavities are needed for the MICE cooling section; fabrication of the first five cavities is complete. We report the cavity fabrication status including cavity design, fabrication techniques and preliminary low power RF measurements.

Morphologies and growth mechanisms of the eutectic particles in as-cast Al-Mg-Sc alloy; Morphologien und Wachstumsmechanismen eutektischer Partikel in Al-Mg-Sc-Legierung im Gusszustand

Energy Technology Data Exchange (ETDEWEB)

Pan, Dejiang; Zhou, Shi' ang; Li, Heng [Hefei Univ. of Technology (China); Zhang, Zhen; Wu, Yucheng [Laboratories of Nonferrous Metal Material and Processing Engineering of Anhui Province, Hefei (China); Li, Ming [Anhui Jianghuai Automobile Co., Ltd, Hefei (China)

2017-04-15

Primary particles with faceted cubic morphology were produced in as-cast Al-Mg alloy due to the addition of Sc. The cross-section of the particles revealed some eutectic structure composed of multilayer of 'Al{sub 3}Sc + α-Al + Al{sub 3}Sc..'. At the cooling rate of 200 - 300 K/s, Al{sub 3}Sc primary phase nucleated initially on oxides within the melt and developed to a cubic structure with a 'cellular-dendritic' mode of growth. The formation of α-Al structural shells was attributed as a reason for the segregation of Mg-rich lamellar dendrites at later stages. A growth mechanism for multilayer structure was proposed using the results presented.

Real-time trace gas sensor using a multimode diode laser and multiple-line integrated cavity enhanced absorption spectroscopy.

Science.gov (United States)

Karpf, Andreas; Rao, Gottipaty N

2015-07-01

We describe and demonstrate a highly sensitive trace gas sensor based on a simplified design that is capable of measuring sub-ppb concentrations of NO2 in tens of milliseconds. The sensor makes use of a relatively inexpensive Fabry-Perot diode laser to conduct off-axis cavity enhanced spectroscopy. The broad frequency range of a multimode Fabry-Perot diode laser spans a large number of absorption lines, thereby removing the need for a single-frequency tunable laser source. The use of cavity enhanced absorption spectroscopy enhances the sensitivity of the sensor by providing a pathlength on the order of 1 km in a small volume. Off-axis alignment excites a large number of cavity modes simultaneously, thereby reducing the sensor's susceptibility to vibration. Multiple-line integrated absorption spectroscopy (where one integrates the absorption spectra over a large number of rovibronic transitions of the molecular species) further improves the sensitivity of detection. Relatively high laser power (∼400  mW) is used to compensate for the low coupling efficiency of a broad linewidth laser to the optical cavity. The approach was demonstrated using a 407 nm diode laser to detect trace quantities of NO2 in zero air. Sensitivities of 750 ppt, 110 ppt, and 65 ppt were achieved using integration times of 50 ms, 5 s, and 20 s respectively.

Bayesian narrowband interference mitigation in SC-FDMA

KAUST Repository

Ali, Anum; Masood, Mudassir; Al-Ghadhban, Samir; Al-Naffouri, Tareq Y.

2015-01-01

This paper presents a novel narrowband interference (NBI) mitigation scheme for SC-FDMA systems. The proposed scheme exploits the frequency domain sparsity of the unknown NBI signal and adopts a low complexity Bayesian sparse recovery procedure. In practice, however, the sparsity of the NBI is destroyed by a grid mismatch between NBI sources and SC-FDMA system. Towards this end, an accurate grid mismatch model is presented and a sparsifying transform is utilized to restore the sparsity of the unknown signal. Numerical results are presented that depict the suitability of the proposed scheme for NBI mitigation.

Bayesian narrowband interference mitigation in SC-FDMA

KAUST Repository

Ali, Anum

2015-08-12

This paper presents a novel narrowband interference (NBI) mitigation scheme for SC-FDMA systems. The proposed scheme exploits the frequency domain sparsity of the unknown NBI signal and adopts a low complexity Bayesian sparse recovery procedure. In practice, however, the sparsity of the NBI is destroyed by a grid mismatch between NBI sources and SC-FDMA system. Towards this end, an accurate grid mismatch model is presented and a sparsifying transform is utilized to restore the sparsity of the unknown signal. Numerical results are presented that depict the suitability of the proposed scheme for NBI mitigation.

Alignment-Annotator web server: rendering and annotating sequence alignments.

Science.gov (United States)

Gille, Christoph; Fähling, Michael; Weyand, Birgit; Wieland, Thomas; Gille, Andreas

2014-07-01

Alignment-Annotator is a novel web service designed to generate interactive views of annotated nucleotide and amino acid sequence alignments (i) de novo and (ii) embedded in other software. All computations are performed at server side. Interactivity is implemented in HTML5, a language native to web browsers. The alignment is initially displayed using default settings and can be modified with the graphical user interfaces. For example, individual sequences can be reordered or deleted using drag and drop, amino acid color code schemes can be applied and annotations can be added. Annotations can be made manually or imported (BioDAS servers, the UniProt, the Catalytic Site Atlas and the PDB). Some edits take immediate effect while others require server interaction and may take a few seconds to execute. The final alignment document can be downloaded as a zip-archive containing the HTML files. Because of the use of HTML the resulting interactive alignment can be viewed on any platform including Windows, Mac OS X, Linux, Android and iOS in any standard web browser. Importantly, no plugins nor Java are required and therefore Alignment-Anotator represents the first interactive browser-based alignment visualization. http://www.bioinformatics.org/strap/aa/ and http://strap.charite.de/aa/. © The Author(s) 2014. Published by Oxford University Press on behalf of Nucleic Acids Research.

Ternary scandium-rich indides Sc{sub 50}T{sub 13}In{sub 3} and Sc{sub 50}Rh{sub 13}In{sub 3}O{sub y} (T = Rh, Ir; y {approx} 8) - synthesis and crystal structure

Energy Technology Data Exchange (ETDEWEB)

Zaremba, R.; Poettgen, R. [Inst. fuer Anorganische und Analytische Chemie, Univ. Muenster (Germany)

2007-12-15

New intermetallic compounds Sc{sub 50}Rh{sub 13.3}In{sub 2.7} and Sc{sub 50}Ir{sub 13.6}In{sub 2.4} and the suboxides Sc{sub 49.2}Rh{sub 13}In{sub 3.8}O{sub 8.8} and Sc{sub 49.2}Rh{sub 13.7}In{sub 2.8}O{sub 8.0} were synthesized from the elements or with Sc{sub 2}O{sub 3} as an oxygen source, respectively, in sealed tantalum tubes in a water-cooled sample chamber of an induction furnace. They crystallize with a new cubic structure type, space group F m anti 3, a = 1772.5(6) pm, wR2 = 0.032, 1111 F{sup 2} values, 34 variables for Sc{sub 50}Rh{sub 13.3}In{sub 2.7}, a = 1766.5(6) pm, wR2 = 0.041, 745 F{sup 2} values, 34 variables for Sc{sub 50}Ir{sub 13.6}In{sub 2.4}, a = 1764.4(2) pm, wR2 = 0.044, 640 F{sup 2} values, 41 variables for Sc{sub 49.2}Rh{sub 13}In{sub 3.8}O{sub 8.8}, and a = 1761.5(6) pm, wR2 = 0.054, 740 F{sup 2} values, 42 variables for Sc{sub 49.2}Rh{sub 13.7}In{sub 2.8}O{sub 8.0}. The main structural motifs are rhodium-centered indium cubes in an fcc like arrangement in which the octahedral and tetrahedral voids are filled by In2Sc{sub 12} and In1Sc{sub 12} icosahedra, respectively, resembling a Li{sub 3}Bi-like structure. The Rh1 (Ir1) and Sc4 atoms lie between these polyhedral units. The oxygen atoms partially fill Sc{sub 6} octahedra in Sc{sub 49.2}Rh{sub 13}In{sub 3.8}O{sub 8.8} and Sc{sub 49.2}Rh{sub 13.7}In{sub 2.8}O{sub 8.0} with Sc-O distances of 214 - 230 pm. These octahedra are condensed via common edges and faces, encapsulating the In2Sc{sub 12} icosahedra. Due to the high scandium content one observes strong Sc-Sc bonding with Sc-Sc distances ranging from 303 to 362 pm in Sc{sub 49.2}Rh{sub 13}In{sub 3.8}O{sub 8.8}. The shortest distances occur for Sc-Rh (267 - 295 pm). The crystal chemical relationship with the Li{sub 3}Bi-related suboxide Ti{sub 12}Sn{sub 3}O{sub 10} is discussed. (orig.)

Static resistance function for steel-plate composite (SC) walls subject to impactive loading

International Nuclear Information System (INIS)

Bruhl, Jakob C.; Varma, Amit H.; Kim, Joo Min

2015-01-01

Highlights: • An idealized static resistance function for SC walls is proposed. • The influence of design parameters on static resistance is explained. • SDOF models can accurately estimate global response of SC walls to missile impact. - Abstract: Steel-plate composite (SC) walls consist of a plain concrete core reinforced with two steel faceplates on the surfaces. Modules (consisting of steel faceplates, shear connectors and tie-bars) can be shop-fabricated and shipped to the site for erection and concrete casting, which expedites construction schedule and thus economy. SC structures have recently been used in nuclear power plant designs and are being considered for the next generation of small modular reactors. Design for impactive and impulsive loading is an important consideration for SC walls in safety-related nuclear facilities. The authors have previously developed design methods to prevent local failure (perforation) of SC walls due to missile impact. This paper presents the development of static resistance functions for use in single-degree-of-freedom (SDOF) analyses to predict the maximum displacement response of SC walls subjected to missile impact and designed to resist local failure (perforation). The static resistance function for SC walls is developed using results of numerical analyses and parametric studies conducted using benchmarked 3D finite element (FE) models. The influence of various design parameters are discussed and used to develop idealized bilinear resistance functions for SC walls with fixed edges and simply supported edges. Results from dynamic non-linear FE analysis of SC panels subjected to rigid missile impact are compared with the maximum displacements predicted by SDOF analyses using the bilinear resistance function.

Static resistance function for steel-plate composite (SC) walls subject to impactive loading

Energy Technology Data Exchange (ETDEWEB)

Bruhl, Jakob C., E-mail: jbruhl@purdue.edu; Varma, Amit H., E-mail: ahvarma@purdue.edu; Kim, Joo Min, E-mail: kim1493@purdue.edu

2015-12-15

Highlights: • An idealized static resistance function for SC walls is proposed. • The influence of design parameters on static resistance is explained. • SDOF models can accurately estimate global response of SC walls to missile impact. - Abstract: Steel-plate composite (SC) walls consist of a plain concrete core reinforced with two steel faceplates on the surfaces. Modules (consisting of steel faceplates, shear connectors and tie-bars) can be shop-fabricated and shipped to the site for erection and concrete casting, which expedites construction schedule and thus economy. SC structures have recently been used in nuclear power plant designs and are being considered for the next generation of small modular reactors. Design for impactive and impulsive loading is an important consideration for SC walls in safety-related nuclear facilities. The authors have previously developed design methods to prevent local failure (perforation) of SC walls due to missile impact. This paper presents the development of static resistance functions for use in single-degree-of-freedom (SDOF) analyses to predict the maximum displacement response of SC walls subjected to missile impact and designed to resist local failure (perforation). The static resistance function for SC walls is developed using results of numerical analyses and parametric studies conducted using benchmarked 3D finite element (FE) models. The influence of various design parameters are discussed and used to develop idealized bilinear resistance functions for SC walls with fixed edges and simply supported edges. Results from dynamic non-linear FE analysis of SC panels subjected to rigid missile impact are compared with the maximum displacements predicted by SDOF analyses using the bilinear resistance function.

Preliminary design study and problem definition for intense CW superconducting deuteron ion linac for fusion material study

International Nuclear Information System (INIS)

Tanabe, Y.; Kakutani, N.; Ota, T.; Yamaguchi, A.; Takeda, O.; Wachi, Y.; Yamazaki, C.; Morii, Y.

1997-01-01

The advantages of superconducting (SC) cavity have been verified for many electron accelerators and the application of SC cavity to high intensity CW ion linacs is currently being considered. These linacs have been required for neutron irradiation tests of materials, transmutation of nuclear waste and so on. An SC linac consisting of SC cavities, SC quadrupole magnets and cryostats, was preliminarily designed to investigate the feasibility of applying to deuteron machine. Beam dynamics analysis was also carried out by using a modified PARMILA code in order to confirm no beam loss. Since radiation damage of superconductors is especially severe for such a machine, data relating to the damage were surveyed and discussed. Moreover, other major facilities such as cryogenic system, radio frequency amplifier and RF control system were considered. Many problems to be solved were defined but no critical issues were found. In consequence, it became clear that SC linac is very attractive and competitive with a room-temperature linac. (orig.)

Sc-Decorated Porous Graphene for High-Capacity Hydrogen Storage: First-Principles Calculations.

Science.gov (United States)

Chen, Yuhong; Wang, Jing; Yuan, Lihua; Zhang, Meiling; Zhang, Cairong

2017-08-02

The generalized gradient approximation (GGA) function based on density functional theory is adopted to investigate the optimized geometrical structure, electron structure and hydrogen storage performance of Sc modified porous graphene (PG). It is found that the carbon ring center is the most stable adsorbed position for a single Sc atom on PG, and the maximum number of adsorbed H₂ molecules is four with the average adsorption energy of -0.429 eV/H₂. By adding a second Sc atom on the other side of the system, the hydrogen storage capacity of the system can be improved effectively. Two Sc atoms located on opposite sides of the PG carbon ring center hole is the most suitable hydrogen storage structure, and the hydrogen storage capacity reach a maximum 9.09 wt % at the average adsorption energy of -0.296 eV/H₂. The adsorption of H₂ molecules in the PG system is mainly attributed to orbital hybridization among H, Sc, and C atoms, and Coulomb attraction between negatively charged H₂ molecules and positively charged Sc atoms.

Establishment and characterization of Roberts syndrome and SC phocomelia model medaka (Oryzias latipes).

Science.gov (United States)

Morita, Akihiro; Nakahira, Kumiko; Hasegawa, Taeko; Uchida, Kaoru; Taniguchi, Yoshihito; Takeda, Shunichi; Toyoda, Atsushi; Sakaki, Yoshiyuki; Shimada, Atsuko; Takeda, Hiroyuki; Yanagihara, Itaru

2012-06-01

Roberts syndrome and SC phocomelia (RBS/SC) are genetic autosomal recessive syndromes caused by establishment of cohesion 1 homolog 2 ( ESCO 2) mutation. RBS/SC appear to have a variety of clinical features, even with the same mutation of the ESCO2 gene. Here, we established and genetically characterized a medaka model of RBS/SC by reverse genetics. The RBS/SC model was screened from a mutant medaka library produced by the Targeting Induced Local Lesions in Genomes method. The medaka mutant carrying the homozygous mutation at R80S in the conserved region of ESCO2 exhibited clinical variety (i.e. developmental arrest with craniofacial and chromosomal abnormalities and embryonic lethality) as characterized in RBS/SC. Moreover, widespread apoptosis and downregulation of some gene expression, including notch1a, were detected in the R80S mutant. The R80S mutant is the animal model for RBS/SC and a valuable resource that provides the opportunity to extend knowledge of ESCO2. Downregulation of some gene expression in the R80S mutant is an important clue explaining non-correlation between genotype and phenotype in RBS/SC. © 2012 The Authors Development, Growth & Differentiation © 2012 Japanese Society of Developmental Biologists.

MuSC is involved in regulating axonal fasciculation of mouse primary vestibular afferents.

Science.gov (United States)

Kawauchi, Daisuke; Kobayashi, Hiroaki; Sekine-Aizawa, Yoko; Fujita, Shinobu C; Murakami, Fujio

2003-10-01

Regulation of axonal fasciculation plays an important role in the precise patterning of neural circuits. Selective fasciculation contributes to the sorting of different types of axons and prevents the misrouting of axons. However, axons must defasciculate once they reach the target area. To study the regulation of fasciculation, we focused on the primary vestibulo-cerebellar afferents (PVAs), which show a dramatic change from fasciculated axon bundles to defasciculated individual axons at their target region, the cerebellar primordium. To understand how fasciculation and defasciculation are regulated in this system, we investigated the roles of murine SC1-related protein (MuSC), a molecule belonging to the immunoglobulin superfamily. We show: (i) by comparing 1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate (Dil) labelling and anti-MuSC immunohistochemistry, that downregulation of MuSC in PVAs during development is concomitant with the defasciculation of PVA axons; (ii) in a binding assay with cells expressing MuSC, that MuSC has cell-adhesive activity via a homophilic binding mechanism, and this activity is increased by multimerization; and (iii) that MuSC also displays neurite outgrowth-promoting activity in vestibular ganglion cultures. These findings suggest that MuSC is involved in axonal fasciculation and its downregulation may help to initiate the defasciculation of PVAs.

Improved Soluble ScFv ELISA Screening Approach for Antibody Discovery Using Phage Display Technology.

Science.gov (United States)

Tohidkia, Mohammad R; Sepehri, Maryam; Khajeh, Shirin; Barar, Jaleh; Omidi, Yadollah

2017-09-01

Phage display technology (PDT) is a powerful tool for the isolation of recombinant antibody (Ab) fragments. Using PDT, target molecule-specific phage-Ab clones are enriched through the "biopanning" process. The individual specific binders are screened by the monoclonal scFv enzyme-linked immunosorbent assay (ELISA) that may associate with inevitable false-negative results. Thus, in this study, three strategies were investigated for optimization of the scFvs screening using Tomlinson I and J libraries, including (1) optimizing the expression of functional scFvs, (2) improving the sensitivity of ELISA, and (3) preparing different samples containing scFvs. The expression of all scFv Abs was significantly enhanced when scFv clones were cultivated in the terrific broth (TB) medium at the optimum temperature of 30 °C. The protein A-conjugated with horseradish peroxidase (HRP) was found to be a well-suited reagent for the detection of Ag-bound scFvs in comparison with either anti-c-myc Ab or the mixing procedure. Based on our findings, it seems there is no universal media supplement for an improved expression of all scFvs derived from both Tomlinson I and J libraries. We thus propose that expression of scFv fragments in a microplate scale is largely dependent on a variety of parameters, in particular the scFv clones and relevant sequences.

Fabrication of mm-wave undulator cavities using deep x-ray lithography

International Nuclear Information System (INIS)

Song, J.J.; Kang, Y.W.; Kustom, R.L.; Lai, B.; Nassiri, A.; Feinerman, A.D.; White, V.; Well, G.M.

1995-01-01

The possibility of fabricating mm-wave radio frequency cavities (100-300 GHz) using deep x-ray lithography (DXRL) is being investigated. The fabrication process includes manufacture of precision x-ray masks, exposure of positive resist by x-ray through the mask, resist development, and electroforming of the final microstructure. Highly precise, two-dimensional features can be machined onto wafers using DXRL. Major challenges are: fabrication of the wafers into three-dimensional rf structures; alignment and overlay accuracy of structures; adhesion of the PMMA on the copper substrate; and selection of a developer to obtain high resolution. Rectangular cavity geometry is best suited to this fabrication technique. A 30- or 84-cell 108-GHz mm-wave structure can serve as an electromagnetic undulator. A mm-wave undulator, which will be discussed later, may have special features compared to the conventional undulator. First harmonic undulator radiation at 5.2 KeV would be possible using the Advanced Photon Source (APS) linac system, which provides a low-emittance electron beam by using an rf thermionic gun with an energy as high as 750-MeV. More detailed rf simulation, heat extraction analysis, beam dynamics using a mm-wave structure, and measurements on lOx larger scale models can be found in these proceedings

Hollow waveguide cavity ringdown spectroscopy

Science.gov (United States)

Dreyer, Chris (Inventor); Mungas, Greg S. (Inventor)

2012-01-01

Laser light is confined in a hollow waveguide between two highly reflective mirrors. This waveguide cavity is used to conduct Cavity Ringdown Absorption Spectroscopy of loss mechanisms in the cavity including absorption or scattering by gases, liquid, solids, and/or optical elements.

Texture Development and Material Flow Behavior During Refill Friction Stir Spot Welding of AlMgSc

Science.gov (United States)

Shen, Junjun; Lage, Sara B. M.; Suhuddin, Uceu F. H.; Bolfarini, Claudemiro; dos Santos, Jorge F.

2018-01-01

The microstructural evolution during refill friction stir spot welding of an AlMgSc alloy was studied. The primary texture that developed in all regions, with the exception of the weld center, was determined to be 〈110〉 fibers and interpreted as a simple shear texture with the 〈110〉 direction aligned with the shear direction. The material flow is mainly driven by two components: the simple shear acting on the horizontal plane causing an inward-directed spiral flow and the extrusion acting on the vertical plane causing an upward-directed or downward-directed flow. Under such a complex material flow, the weld center, which is subjected to minimal local strain, is the least recrystallized. In addition to the geometric effects of strain and grain subdivision, thermally activated high-angle grain boundary migration, particularly continuous dynamic recrystallization, drives the formation of refined grains in the stirred zone.

Rotary condenser for SC2

CERN Multimedia

1975-01-01

During 1975 the SC2 performance was improved among other things by redesigning some of the elements of the ROTCO (Annual Report 1975, p. 55). The photo shows an interior wiew of the housing of the rotary condenser and of the sixteen sets of shaped stator blades.

Superconducting Radio-Frequency Cavities

Science.gov (United States)

Padamsee, Hasan S.

2014-10-01

Superconducting cavities have been operating routinely in a variety of accelerators with a range of demanding applications. With the success of completed projects, niobium cavities have become an enabling technology, offering upgrade paths for existing facilities and pushing frontier accelerators for nuclear physics, high-energy physics, materials science, and the life sciences. With continued progress in basic understanding of radio-frequency superconductivity, the performance of cavities has steadily improved to approach theoretical capabilities.

Magnetically aligned H I fibers and the rolling hough transform

Energy Technology Data Exchange (ETDEWEB)

Clark, S. E.; Putman, M. E.; Peek, J. E. G. [Department of Astronomy, Columbia University, New York, NY (United States)

2014-07-01

We present observations of a new group of structures in the diffuse Galactic interstellar medium (ISM): slender, linear H I features we dub 'fibers' that extend for many degrees at high Galactic latitude. To characterize and measure the extent and strength of these fibers, we present the Rolling Hough Transform, a new machine vision method for parameterizing the coherent linearity of structures in the image plane. With this powerful new tool we show that the fibers are oriented along the interstellar magnetic field as probed by starlight polarization. We find that these low column density (N{sub H} {sub I}≃5×10{sup 18} cm{sup –2}) fiber features are most likely a component of the local cavity wall, about 100 pc away. The H I data we use to demonstrate this alignment at high latitude are from the Galactic Arecibo L-Band Feed Array H I (GALFA-H I) Survey and the Parkes Galactic All Sky Survey. We find better alignment in the higher resolution GALFA-H I data, where the fibers are more visually evident. This trend continues in our investigation of magnetically aligned linear features in the Riegel-Crutcher H I cold cloud, detected in the Southern Galactic Plane Survey. We propose an application of the RHT for estimating the field strength in such a cloud, based on the Chandrasekhar-Fermi method. We conclude that data-driven, quantitative studies of ISM morphology can be very powerful predictors of underlying physical quantities.

A SURVEY OF CORONAL CAVITY DENSITY PROFILES

International Nuclear Information System (INIS)

Fuller, J.; Gibson, S. E.

2009-01-01

Coronal cavities are common features of the solar corona that appear as darkened regions at the base of coronal helmet streamers in coronagraph images. Their darkened appearance indicates that they are regions of lowered density embedded within the comparatively higher density helmet streamer. Despite interfering projection effects of the surrounding helmet streamer (which we refer to as the cavity rim), Fuller et al. have shown that under certain conditions it is possible to use a Van de Hulst inversion of white-light polarized brightness (pB) data to calculate the electron density of both the cavity and cavity rim plasma. In this article, we apply minor modifications to the methods of Fuller et al. in order to improve the accuracy and versatility of the inversion process, and use the new methods to calculate density profiles for both the cavity and cavity rim in 24 cavity systems. We also examine trends in cavity morphology and how departures from the model geometry affect our density calculations. The density calculations reveal that in all 24 cases the cavity plasma has a flatter density profile than the plasma of the cavity rim, meaning that the cavity has a larger density depletion at low altitudes than it does at high altitudes. We find that the mean cavity density is over four times greater than that of a coronal hole at an altitude of 1.2 R sun and that every cavity in the sample is over twice as dense as a coronal hole at this altitude. Furthermore, we find that different cavity systems near solar maximum span a greater range in density at 1.2 R sun than do cavity systems near solar minimum, with a slight trend toward higher densities for systems nearer to solar maximum. Finally, we found no significant correlation of cavity density properties with cavity height-indeed, cavities show remarkably similar density depletions-except for the two smallest cavities that show significantly greater depletion.

Low-β SC linacs: past, present, and future

International Nuclear Information System (INIS)

Bollinger, L. M.

1998-01-01

This paper is a general review of superconducting low-β technology and applications from its beginning in 1969 into the near-term future. The emphasis is on studies of accelerating resonators and on SC linacs that boost the energy of heavy-ion beams from tandem electrostatic accelerators used for nuclear-physics research. Other topics are positive-ion SC injectors to replace tandems and the need for accelerating structures with β outside of the present proven range, 0.008 < β < 0.2

radiofrequency cavity

CERN Multimedia

1988-01-01

The pulse of a particle accelerator. 128 of these radio frequency cavities were positioned around CERN's 27-kilometre LEP ring to accelerate electrons and positrons. The acceleration was produced by microwave electric oscillations at 352 MHz. The electrons and positrons were grouped into bunches, like beads on a string, and the copper sphere at the top stored the microwave energy between the passage of individual bunches. This made for valuable energy savings as it reduced the heat generated in the cavity.

Millimeter wave surface resistance of grain-aligned Y1Ba2Cu3O(x) bulk material

Science.gov (United States)

Wosik, J.; Kranenburg, R. A.; Wolfe, J. C.; Selvamanickam, V.; Salama, K.

1991-01-01

Measurements of the millimeter wave surface resistance of grain-aligned YBa2Cu3O(x) bulk material grown by a liquid phase process are reported. The measurements were performed by replacing the endplate of a TE011 cylindrical copper cavity with the superconducting sample. Surface resistance was measured for samples with surfaces oriented perpendicular and parallel to the c-axis of the grains. It is shown that, for the parallel configuration, the surface resistance at 77 K and 80 GHz is typically near 100 milliohms. For a very well-aligned sample with a very low density of Y2BaCuO(y) precipitates, measured in the perpendicular configuration, the transition width (10-90 percent) is about 2 K, and the surface resistance is less than 50 milliohms at 88 K. The effect of microstructure on surface resistance is discussed.

RevTrans: multiple alignment of coding DNA from aligned amino acid sequences

DEFF Research Database (Denmark)

Wernersson, Rasmus; Pedersen, Anders Gorm

2003-01-01

The simple fact that proteins are built from 20 amino acids while DNA only contains four different bases, means that the 'signal-to-noise ratio' in protein sequence alignments is much better than in alignments of DNA. Besides this information-theoretical advantage, protein alignments also benefit...... proteins. It is therefore preferable to align coding DNA at the amino acid level and it is for this purpose we have constructed the program RevTrans. RevTrans constructs a multiple DNA alignment by: (i) translating the DNA; (ii) aligning the resulting peptide sequences; and (iii) building a multiple DNA...

Earth-ionosphere cavity

International Nuclear Information System (INIS)

Tran, A.; Polk, C.

1976-01-01

To analyze ELF wave propagation in the earth-ionosphere cavity, a flat earth approximation may be derived from the exact equations, which are applicable to the spherical cavity, by introducing a second-order or Debye approximation for the spherical Hankel functions. In the frequency range 3 to 30 Hz, however, the assumed conditions for the Debye approximation are not satisfied. For this reason an exact evaluation of the spherical Hankel functions is used to study the effects of the flat earth approximation on various propagation and resonance parameters. By comparing the resonance equation for a spherical cavity with its flat earth counterpart and by assuming that the surface impedance Z/sub i/ at the upper cavity boundary is known, the relation between the eigenvalue ν and S/sub v/, the sine of the complex angle of incidence at the lower ionosphere boundary, is established as ν(ν + 1) = (kaS/sub v/) 2 . It is also shown that the approximation ν(ν + 1) approximately equals (ν + 1/2) 2 which was used by some authors is not adequate below 30 Hz. Numerical results for both spherical and planar stratification show that (1) planar stratification is adequate for the computation of the lowest three ELF resonance frequencies to within 0.1 Hz; (2) planar stratification will lead to errors in cavity Q and wave attenuation which increase with frequency; (3) computation of resonance frequencies to within 0.1 Hz requires the extension of the lower boundary of the ionosphere to a height where the ratio of conduction current to displacement current, (sigma/ωepsilon 0 ), is less than 0.3; (4) atmospheric conductivity should be considered down to ground level in computing cavity Q and wave attenuation

Cavity design programs

International Nuclear Information System (INIS)

Nelson, E.M.

1996-01-01

Numerous computer programs are available to help accelerator physicists and engineers model and design accelerator cavities and other microwave components. This article discusses the problems these programs solve and the principles upon which these programs are based. Some examples of how these programs are used in the design of accelerator cavities are also given

SC-HTGR Performance Impact for Arid Sites

International Nuclear Information System (INIS)

Lommers, L.; Geschwindt, J.; Southworth, F.; Shahrokhi, F.

2014-01-01

The SC-HTGR provides high temperature steam which can support industrial process heat applications as well as high efficiency electricity generation. The increased generating efficiency resulting from using high steam temperature provides greater plant output than lower temperature concepts, and it also reduces the fraction of waste heat which must be rejected. This capability is particularly attractive for sites with little or no water for heat rejection. This high temperature capability provides greater flexibility for these sites, and it results in a smaller performance penalty than for lower temperature systems when dry cooling must be used. The performance of the SC-HTGR for a conventional site with wet cooling is discussed first. Then the performance for arid sites is evaluated. Dry cooling performance is evaluated for both moderately arid sites and very hot sites. Offdesign performance of the dry cooling system under extreme conditions is also considered. Finally, operating strategies are explored for sites where some cooling water may be available but only in very limited quantities. Results of these assessments confirm that the higher operating temperatures of the SC-HTGR are very beneficial for arid sites, providing significant advantages for both gross and net power generation. (author)

Partial Cavity Flows at High Reynolds Numbers

Science.gov (United States)

Makiharju, Simo; Elbing, Brian; Wiggins, Andrew; Dowling, David; Perlin, Marc; Ceccio, Steven

2009-11-01

Partial cavity flows created for friction drag reduction were examined on a large-scale. Partial cavities were investigated at Reynolds numbers up to 120 million, and stable cavities with frictional drag reduction of more than 95% were attained at optimal conditions. The model used was a 3 m wide and 12 m long flat plate with a plenum on the bottom. To create the partial cavity, air was injected at the base of an 18 cm backwards-facing step 2.1 m from the leading edge. The geometry at the cavity closure was varied for different flow speeds to optimize the closure of the cavity. Cavity gas flux, thickness, frictional loads, and cavity pressures were measured over a range of flow speeds and air injection fluxes. High-speed video was used extensively to investigate the unsteady three dimensional cavity closure, the overall cavity shape and oscillations.

Technical Training: CERN Technical Training 2004 - New Short Courses (SC) on Microsoft Outlook

CERN Multimedia

Monique Duval

2004-01-01

The CERN Technical Training programme is now proposing a new format for courses on Microsoft Outlook. Three two-hours Short Courses (SC) will cover basic and advanced functionalities of the recommended mail client for email at CERN. Each module can be followed independently. The next scheduled sessions will take place as follows: Outlook (SC I): E-mail. Next session: 31.8.2004 (9h00-11h00) Outlook (SC II): Calendar, Tasks and Notes. Next session: 31.8.2004 (14h00-16h00) Outlook (SC III): Meetings and Delegation. Next session: 7.9.2004 (14h00-16h00) In particular, SC I will cover how to open, create and send email, work with attachments, use stationery, organise mail, and work with the address book, SC II will show how to work with the calendar, tasks and notes, and SC III will cover how to organise and manage meetings, work with meeting requests, share tasks, and use email and calendar delegation. The number of participants to each session is limited to 8. The instructor is English-French bilingual, and s...

TEM observations of crack tip: cavity interactions

International Nuclear Information System (INIS)

Horton, J.A.; Ohr, S.M.; Jesser, W.A.

1981-01-01

Crack tip-cavity interactions have been studied by performing room temperature deformation experiments in a transmission electron microscope on ion-irradiated type 316 stainless steel with small helium containing cavities. Slip dislocations emitted from a crack tip cut, sheared, and thereby elongated cavities without a volume enlargement. As the crack tip approached, a cavity volume enlargement occurred. Instead of the cavities continuing to enlarge until they touch, the walls between the cavities fractured. Fracture surface dimples do not correlate in size or density with these enlarged cavities

Sc-Decorated Porous Graphene for High-Capacity Hydrogen Storage: First-Principles Calculations

Directory of Open Access Journals (Sweden)

Yuhong Chen

2017-08-01

Full Text Available The generalized gradient approximation (GGA function based on density functional theory is adopted to investigate the optimized geometrical structure, electron structure and hydrogen storage performance of Sc modified porous graphene (PG. It is found that the carbon ring center is the most stable adsorbed position for a single Sc atom on PG, and the maximum number of adsorbed H2 molecules is four with the average adsorption energy of −0.429 eV/H2. By adding a second Sc atom on the other side of the system, the hydrogen storage capacity of the system can be improved effectively. Two Sc atoms located on opposite sides of the PG carbon ring center hole is the most suitable hydrogen storage structure, and the hydrogen storage capacity reach a maximum 9.09 wt % at the average adsorption energy of −0.296 eV/H2. The adsorption of H2 molecules in the PG system is mainly attributed to orbital hybridization among H, Sc, and C atoms, and Coulomb attraction between negatively charged H2 molecules and positively charged Sc atoms.

Emission ability of La-Sc-Mo cathode

International Nuclear Information System (INIS)

Yang Jiancan; Nie Zuoren; Xi Xiaoli; Wang Yiman

2004-01-01

In this paper La-Sc-Mo cathode has been prepared and its electron emission ability was measured. This type of cathode shows good electron emission performance that the saturated current density is 6.74 A cm -1 and the work function is about 2.59 eV at 1300 deg. C, which is much lower than thoriated tungsten cathode (Th-W). So it is a potential cathode to replace the Th-W cathode with radioactive pollution. Surface analysis shows that good emission ability due to the 20 nm surplus La layer and the element Sc may do good to the La diffusion to the surface

STRUCTURAL ANALYSIS OF SUPERCONDUCTING ACCELERATOR CAVITIES

International Nuclear Information System (INIS)

Schrage, D.

2000-01-01

The static and dynamic structural behavior of superconducting cavities for various projects was determined by finite element structural analysis. The β = 0.61 cavity shape for the Neutron Science Project was studied in detail and found to meet all design requirements if fabricated from five millimeter thick material with a single annular stiffener. This 600 MHz cavity will have a Lorentz coefficient of minus1.8 Hz/(Mv/meter) 2 and a lowest structural resonance of more than 100 Hz. Cavities at β = 0.48, 0.61, and 0.77 were analyzed for a Neutron Science Project concept which would incorporate 7-cell cavities. The medium and high beta cavities were found to meet all criteria but it was not possible to generate a β = 0.48 cavity with a Lorentz coefficient of less than minus3 Hz/(Mv/meter) 2

Superconducting cavities developments efforts at RRCAT

International Nuclear Information System (INIS)

Puntambekar, A.; Bagre, M.; Dwivedi, J.; Shrivastava, P.; Mundra, G.; Joshi, S.C.; Potukuchi, P.N.

2011-01-01

Superconducting RE cavities are the work-horse for many existing and proposed linear accelerators. Raja Ramanna Centre for Advanced Technology (RRCAT) has initiated a comprehensive R and D program for development of Superconducting RF cavities suitable for high energy accelerator application like SNS and ADS. For the initial phase of technology demonstration several prototype 1.3 GHz single cell-cavities have been developed. The work began with development of prototype single cell cavities in aluminum and copper. This helped in development of cavity manufacturing process, proving various tooling and learning on various mechanical and RF qualification processes. The parts manufacturing was done at RRCAT and Electron beam welding was carried out at Indian industry. These cavities further served during commissioning trials for various cavity processing infrastructure being developed at RRCAT and are also a potential candidate for Niobium thin film deposition R and D. Based on the above experience, few single cell cavities were developed in fine grain niobium. The critical technology of forming and machining of niobium and the intermediate RF qualification were developed at RRCAT. The EB welding of bulk niobium cavities was carried out in collaboration with IUAC, New Delhi at their facility. As a next logical step efforts are now on for development of multicell cavities. The prototype dumbbells and end group made of aluminium, comprising of RF and HOM couplers ports have also been developed, with their LB welding done at Indian industry. In this paper we shall present the development efforts towards manufacturing of 1.3 GHz single cell cavities and their initial processing and qualification. (author)

Effect of cavity disinfectants on antibacterial activity and microtensile bond strength in class I cavity.

Science.gov (United States)

Kim, Bo-Ram; Oh, Man-Hwan; Shin, Dong-Hoon

2017-05-31

This study was performed to compare the antibacterial activities of three cavity disinfectants [chlorhexidine (CHX), NaOCl, urushiol] and to evaluate their effect on the microtensile bond strength of Scotchbond Universal Adhesive (3M-ESPE, St. Paul, MN, USA) in class I cavities. In both experiments, class I cavities were prepared in dentin. After inoculation with Streptococcus mutans, the cavities of control group were rinsed and those of CHX, NaOCl and urushiol groups were treated with each disinfectant. Standardized amounts of dentin chips were collected and number of S. mutans was determined. Following the same cavity treatment, same adhesive was applied in etch-and-rinse mode. Then, microtensile bond strength was evaluated. The number of S. mutans was significantly reduced in the cavities treated with CHX, NaOCl, and urushiol compared with control group (p<0.05). However, there was a significant bond strength reduction in NaOCl group, which showed statistical difference compared to the other groups (p<0.05).

21 CFR 872.3260 - Cavity varnish.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Cavity varnish. 872.3260 Section 872.3260 Food and... DENTAL DEVICES Prosthetic Devices § 872.3260 Cavity varnish. (a) Identification. Cavity varnish is a device that consists of a compound intended to coat a prepared cavity of a tooth before insertion of...

Color fading of the blue compliance indicator encapsulated in removable clear Invisalign Teen® aligners.

Science.gov (United States)

Schott, Timm Cornelius; Göz, Gernot

2011-03-01

To evaluate the color fading in aqueous solutions of the blue dot wear-compliance indicators of the Invisalign Teen® System outside the oral cavity. The compliance indicators in the Invisalign Teen aligners were tested for color resistance in various aqueous models with no saliva involved. Color fading was observed as a function of time, pH, and temperature while compliance indicators were stored in drinking water or sour soft drinks and in conjunction with the use of cleaning tablets and a dishwasher. The findings of color fading were consistent with the color changes observed when the aligners were being worn by patients. Color fading, notably as observed in connection with acidic soft drinks and cleaning techniques, introduces uncertainty into the assessment of actual patient compliance, as reflected by the fading colors of compliance indicators. Compliance indicators are not immune to simple intentional or unintentional manipulations. Therefore, they can best show an estimate of wear time but cannot be recommended as objective wear-time indicators.

Geometric Model of a Coronal Cavity

Science.gov (United States)

Kucera, Therese A.; Gibson, S. E.; Ratawicki, D.; Dove, J.; deToma, G.; Hao, J.; Hudson, H. S.; Marque, C.; McIntosh, P. S.; Reeves, K. K.;

accelerating cavity from LEP

CERN Multimedia

This is an accelerating cavity from LEP, with a layer of niobium on the inside. Operating at 4.2 degrees above absolute zero, the niobium is superconducting and carries an accelerating field of 6 million volts per metre with negligible losses. Each cavity has a surface of 6 m2. The niobium layer is only 1.2 microns thick, ten times thinner than a hair. Such a large area had never been coated to such a high accuracy. A speck of dust could ruin the performance of the whole cavity so the work had to be done in an extremely clean environment. These challenging requirements pushed European industry to new achievements. 256 of these cavities are now used in LEP to double the energy of the particle beams.

DIMM-SC: a Dirichlet mixture model for clustering droplet-based single cell transcriptomic data.

Science.gov (United States)

Sun, Zhe; Wang, Ting; Deng, Ke; Wang, Xiao-Feng; Lafyatis, Robert; Ding, Ying; Hu, Ming; Chen, Wei

2018-01-01

Single cell transcriptome sequencing (scRNA-Seq) has become a revolutionary tool to study cellular and molecular processes at single cell resolution. Among existing technologies, the recently developed droplet-based platform enables efficient parallel processing of thousands of single cells with direct counting of transcript copies using Unique Molecular Identifier (UMI). Despite the technology advances, statistical methods and computational tools are still lacking for analyzing droplet-based scRNA-Seq data. Particularly, model-based approaches for clustering large-scale single cell transcriptomic data are still under-explored. We developed DIMM-SC, a Dirichlet Mixture Model for clustering droplet-based Single Cell transcriptomic data. This approach explicitly models UMI count data from scRNA-Seq experiments and characterizes variations across different cell clusters via a Dirichlet mixture prior. We performed comprehensive simulations to evaluate DIMM-SC and compared it with existing clustering methods such as K-means, CellTree and Seurat. In addition, we analyzed public scRNA-Seq datasets with known cluster labels and in-house scRNA-Seq datasets from a study of systemic sclerosis with prior biological knowledge to benchmark and validate DIMM-SC. Both simulation studies and real data applications demonstrated that overall, DIMM-SC achieves substantially improved clustering accuracy and much lower clustering variability compared to other existing clustering methods. More importantly, as a model-based approach, DIMM-SC is able to quantify the clustering uncertainty for each single cell, facilitating rigorous statistical inference and biological interpretations, which are typically unavailable from existing clustering methods. DIMM-SC has been implemented in a user-friendly R package with a detailed tutorial available on www.pitt.edu/∼wec47/singlecell.html. wei.chen@chp.edu or hum@ccf.org. Supplementary data are available at Bioinformatics online. © The Author

Fundamental limitations of cavity-assisted atom interferometry

Science.gov (United States)

Dovale-Álvarez, M.; Brown, D. D.; Jones, A. W.; Mow-Lowry, C. M.; Miao, H.; Freise, A.

2017-11-01

Atom interferometers employing optical cavities to enhance the beam splitter pulses promise significant advances in science and technology, notably for future gravitational wave detectors. Long cavities, on the scale of hundreds of meters, have been proposed in experiments aiming to observe gravitational waves with frequencies below 1 Hz, where laser interferometers, such as LIGO, have poor sensitivity. Alternatively, short cavities have also been proposed for enhancing the sensitivity of more portable atom interferometers. We explore the fundamental limitations of two-mirror cavities for atomic beam splitting, and establish upper bounds on the temperature of the atomic ensemble as a function of cavity length and three design parameters: the cavity g factor, the bandwidth, and the optical suppression factor of the first and second order spatial modes. A lower bound to the cavity bandwidth is found which avoids elongation of the interaction time and maximizes power enhancement. An upper limit to cavity length is found for symmetric two-mirror cavities, restricting the practicality of long baseline detectors. For shorter cavities, an upper limit on the beam size was derived from the geometrical stability of the cavity. These findings aim to aid the design of current and future cavity-assisted atom interferometers.

4SC-202 activates ASK1-dependent mitochondrial apoptosis pathway to inhibit hepatocellular carcinoma cells

International Nuclear Information System (INIS)

Fu, Meili; Wan, Fuqiang; Li, Zhengling; Zhang, Fenghua

2016-01-01

The aim of the present study is to investigate the potential anti-hepatocellular carcinoma (HCC) cell activity by 4SC-202, a novel class I HDAC inhibitor (HDACi). The associated signaling mechanisms were also analyzed. We showed that 4SC-202 treatment induced potent cytotoxic and proliferation–inhibitory activities against established HCC cell lines (HepG2, HepB3, SMMC-7721) and patient-derived primary HCC cells. Further, adding 4SC-202 in HCC cells activated mitochondrial apoptosis pathway, which was evidenced by mitochondrial permeability transition pore (mPTP) opening, cytochrome C cytosol release and caspase-3/-9 activation. Inhibition of this apoptosis pathway, by caspase-3/-9 inhibitors, mPTP blockers, or by shRNA-mediated knockdown of cyclophilin-D (Cyp-D, a key component of mPTP), significantly attenuated 4SC-202-induced HCC cell death and apoptosis. Reversely, over-expression of Cyp-D enhanced 4SC-202's sensitivity in HCC cells. Further studies showed that 4SC-202 induced apoptosis signal-regulating kinase 1 (ASK1) activation, causing it translocation to mitochondria and physical association with Cyp-D. This mitochondrial ASK1-Cyp-D complexation appeared required for mediating 4SC-202-induced apoptosis activation. ASK1 stable knockdown by targeted-shRNAs largely inhibited 4SC-202-induced mPTP opening, cytochrome C release, and following HCC cell apoptotic death. Together, we suggest that 4SC-202 activates ASK1-dependent mitochondrial apoptosis pathway to potently inhibit human HCC cells. - Highlights: • 4SC-202 exerts potent anti-proliferative and cytotoxic activity against established/primary HCC cells. • SC-202-induced anti-HCC cell activity relies on caspase-dependent apoptosis activation. • 4SC-202 activates Cyp-D-dependent mitochondrial apoptosis pathway in HCC cells. • 4SC-202 activates ASK1 in HCC cells, causing it translocation to mitochondria. • Mitochondrial ASK1-Cyp-D complexation mediates 4SC-202's activity in HCC cells.

4SC-202 activates ASK1-dependent mitochondrial apoptosis pathway to inhibit hepatocellular carcinoma cells

Energy Technology Data Exchange (ETDEWEB)

Fu, Meili, E-mail: fumeilidrlinyi@tom.com [Department of Infectious Disease, Linyi People' s Hospital, Linyi 276000 (China); Wan, Fuqiang [Department of Head and Neck Surgery, Linyi Tumor Hospital, Linyi 276000 (China); Li, Zhengling [Department of Nursing, Tengzhou Central People' s Hospital, Tengzhou 277500 (China); Zhang, Fenghua [Department of Operating Room, Linyi People' s Hospital, Linyi 276000 (China)

2016-03-04

The aim of the present study is to investigate the potential anti-hepatocellular carcinoma (HCC) cell activity by 4SC-202, a novel class I HDAC inhibitor (HDACi). The associated signaling mechanisms were also analyzed. We showed that 4SC-202 treatment induced potent cytotoxic and proliferation–inhibitory activities against established HCC cell lines (HepG2, HepB3, SMMC-7721) and patient-derived primary HCC cells. Further, adding 4SC-202 in HCC cells activated mitochondrial apoptosis pathway, which was evidenced by mitochondrial permeability transition pore (mPTP) opening, cytochrome C cytosol release and caspase-3/-9 activation. Inhibition of this apoptosis pathway, by caspase-3/-9 inhibitors, mPTP blockers, or by shRNA-mediated knockdown of cyclophilin-D (Cyp-D, a key component of mPTP), significantly attenuated 4SC-202-induced HCC cell death and apoptosis. Reversely, over-expression of Cyp-D enhanced 4SC-202's sensitivity in HCC cells. Further studies showed that 4SC-202 induced apoptosis signal-regulating kinase 1 (ASK1) activation, causing it translocation to mitochondria and physical association with Cyp-D. This mitochondrial ASK1-Cyp-D complexation appeared required for mediating 4SC-202-induced apoptosis activation. ASK1 stable knockdown by targeted-shRNAs largely inhibited 4SC-202-induced mPTP opening, cytochrome C release, and following HCC cell apoptotic death. Together, we suggest that 4SC-202 activates ASK1-dependent mitochondrial apoptosis pathway to potently inhibit human HCC cells. - Highlights: • 4SC-202 exerts potent anti-proliferative and cytotoxic activity against established/primary HCC cells. • SC-202-induced anti-HCC cell activity relies on caspase-dependent apoptosis activation. • 4SC-202 activates Cyp-D-dependent mitochondrial apoptosis pathway in HCC cells. • 4SC-202 activates ASK1 in HCC cells, causing it translocation to mitochondria. • Mitochondrial ASK1-Cyp-D complexation mediates 4SC-202's activity in HCC cells.

Optimization of photonic crystal cavities

DEFF Research Database (Denmark)

Wang, Fengwen; Sigmund, Ole

2017-01-01

We present optimization of photonic crystal cavities. The optimization problem is formulated to maximize the Purcell factor of a photonic crystal cavity. Both topology optimization and air-hole-based shape optimization are utilized for the design process. Numerical results demonstrate...... that the Purcell factor of the photonic crystal cavity can be significantly improved through optimization....

TESLA superconducting RF cavity development

International Nuclear Information System (INIS)

Koepke, K.

1995-01-01

The TESLA collaboration has made steady progress since its first official meeting at Cornell in 1990. The infrastructure necessary to assemble and test superconducting rf cavities has been installed at the TESLA Test Facility (TTF) at DESY. 5-cell, 1.3 GHz cavities have been fabricated and have reached accelerating fields of 25 MV/m. Full sized 9-cell copper cavities of TESLA geometry have been measured to verify the higher order modes present and to evaluate HOM coupling designs. The design of the TESLA 9-cell cavity has been finalized and industry has started delivery. Two prototype 9-cell niobium cavities in their first tests have reached accelerating fields of 10 MV/m and 15 MV/m in a vertical dewar after high peak power (HPP) conditioning. The first 12 m TESLA cryomodule that will house 8 9-cell cavities is scheduled to be delivered in Spring 1995. A design report for the TTF is in progress. The TTF test linac is scheduled to be commissioned in 1996/1997. (orig.)

Thermoelectric performance of functionalized Sc2C MXenes

KAUST Repository

Kumar, S.; Schwingenschlö gl, Udo

2016-01-01

Functionalization of the MXene Sc2C, which has the rare property to realize semiconducting states for various functionalizations including O, F, and OH, is studied with respect to the electronic and thermal behavior. The lowest lattice thermal conductivity is obtained for OH functionalization and an additional 30% decrease can be achieved by confining the phonon mean free path to 100 nm. Despite a relatively low Seebeck coefficient, Sc2C(OH)2 is a candidate for intermediate-temperature thermoelectric applications due to compensation by a high electrical conductivity and very low lattice thermal conductivity.

Thermoelectric performance of functionalized Sc2C MXenes

KAUST Repository

Kumar, S.

2016-07-05

Functionalization of the MXene Sc2C, which has the rare property to realize semiconducting states for various functionalizations including O, F, and OH, is studied with respect to the electronic and thermal behavior. The lowest lattice thermal conductivity is obtained for OH functionalization and an additional 30% decrease can be achieved by confining the phonon mean free path to 100 nm. Despite a relatively low Seebeck coefficient, Sc2C(OH)2 is a candidate for intermediate-temperature thermoelectric applications due to compensation by a high electrical conductivity and very low lattice thermal conductivity.

An economical wireless cavity-nest viewer

Science.gov (United States)

Daniel P. Huebner; Sarah R. Hurteau

2007-01-01

Inspection of cavity nests and nest boxes is often required during studies of cavity-nesting birds, and fiberscopes and pole-mounted video cameras are sometimes used for such inspection. However, the cost of these systems may be prohibitive for some potential users. We describe a user-built, wireless cavity viewer that can be used to access cavities as high as 15 m and...

MUON DETECTORS: ALIGNMENT

CERN Multimedia

S. Szillasi

2013-01-01

The CMS detector has been gradually opened and whenever a wheel became exposed the first operation was the removal of the MABs, the sensor structures of the Hardware Barrel Alignment System. By the last days of June all 36 MABs have arrived at the Alignment Lab at the ISR where, as part of the Alignment Upgrade Project, they are refurbished with new Survey target holders. Their electronic checkout is on the way and finally they will be recalibrated. During LS1 the alignment system will be upgraded in order to allow more precise reconstruction of the MB4 chambers in Sector 10 and Sector 4. This requires new sensor components, so called MiniMABs (pictured below), that have already been assembled and calibrated. Image 6: Calibrated MiniMABs are ready for installation For the track-based alignment, the systematic uncertainties of the algorithm are under scrutiny: this study will enable the production of an improved Monte Carlo misalignment scenario and to update alignment position errors eventually, crucial...

Energy Levels and Radiative Rates for Transitions in F-like Sc XIII and Ne-like Sc XII and Y XXX

Directory of Open Access Journals (Sweden)

Kanti M. Aggarwal

2018-05-01

Full Text Available Energy levels, radiative rates and lifetimes are reported for F-like Sc XIII and Ne-like Sc XII and Y XXX for which the general-purpose relativistic atomic structure package (GRASP has been adopted. For all three ions, limited data exist in the literature but comparisons have been made wherever possible to assess the accuracy of the calculations. In the present work, the lowest 102, 125 and 139 levels have been considered for the respective ions. Additionally, calculations have also been performed with the flexible atomic code (FAC to (particularly confirm the accuracy of energy levels.

Forward Modeling of a Coronal Cavity

Science.gov (United States)

Kucera, T. A.; Gibson, S. E.; Schmit, D. J.

2011-01-01

We apply a forward model of emission from a coronal cavity in an effort to determine the temperature and density distribution in the cavity. Coronal cavities are long, low-density structures located over filament neutral lines and are often seen as dark elliptical features at the solar limb in white light, EUV and X-rays. When these structures erupt they form the cavity portions of CMEs The model consists of a coronal streamer model with a tunnel-like cavity with elliptical cross-section and a Gaussian variation of height along the tunnel length. Temperature and density can be varied as a function of altitude both in the cavity and streamer. We apply this model to a cavity observed in Aug. 2007 by a wide array of instruments including Hinode/EIS, STEREO/EUVI and SOHO/EIT. Studies such as these will ultimately help us understand the the original structures which erupt to become CMEs and ICMES, one of the prime Solar Orbiter objectives.

An ideal scintillator – ZnO:Sc for sub-nanosecond pulsed radiation detection

Energy Technology Data Exchange (ETDEWEB)

Zhang, Kan, E-mail: zhangkan8414@163.com [Northwest Institute of Nuclear Technology, Xi’an 710024 (China); Ouyang, Xiaoping [Northwest Institute of Nuclear Technology, Xi’an 710024 (China); Xi’an Jiaotong University, Xi’an 710049 (China); Song, Zhaohui; Han, Hetong [Northwest Institute of Nuclear Technology, Xi’an 710024 (China); Zuo, Yanbin [China Nonferrous Metal Guilin Research Institute of Geology for Mineral Resource, Guilin 541004 (China); Guan, Xingyin [Northwest Institute of Nuclear Technology, Xi’an 710024 (China); Xi’an Jiaotong University, Xi’an 710049 (China); Tan, Xinjian; Zhang, Zichuan; Liu, Junhong [Northwest Institute of Nuclear Technology, Xi’an 710024 (China)

2014-08-21

ZnO-based scintillators are particularly well suited for use as ultrafast pulsed radiation detectors which have shown broad application prospects in various fields such as the inertial confinement fusion (ICF) diagnosis, the nuclear reaction mechanism, etc. Using the hydro-thermal method, a ZnO single-crystal doped with Scandium (ZnO:Sc) sample was prepared. As a new ZnO-based scintillator, the scintillation characteristics of ZnO:Sc have not been reported previously. In this paper, optical and scintillation characteristics of ZnO:Sc single-crystal were studied. Also a scintillation detector based on ZnO:Sc was designed. Excited by the alpha-particle, the rise time of ZnO:Sc detectors was from 162.5 to 170.7 ps, and the fall time was from 300.4 to 328.8 ps.

An ideal scintillator – ZnO:Sc for sub-nanosecond pulsed radiation detection

International Nuclear Information System (INIS)

Zhang, Kan; Ouyang, Xiaoping; Song, Zhaohui; Han, Hetong; Zuo, Yanbin; Guan, Xingyin; Tan, Xinjian; Zhang, Zichuan; Liu, Junhong

2014-01-01

ZnO-based scintillators are particularly well suited for use as ultrafast pulsed radiation detectors which have shown broad application prospects in various fields such as the inertial confinement fusion (ICF) diagnosis, the nuclear reaction mechanism, etc. Using the hydro-thermal method, a ZnO single-crystal doped with Scandium (ZnO:Sc) sample was prepared. As a new ZnO-based scintillator, the scintillation characteristics of ZnO:Sc have not been reported previously. In this paper, optical and scintillation characteristics of ZnO:Sc single-crystal were studied. Also a scintillation detector based on ZnO:Sc was designed. Excited by the alpha-particle, the rise time of ZnO:Sc detectors was from 162.5 to 170.7 ps, and the fall time was from 300.4 to 328.8 ps

Replication of micro and nano-features on iPP by injection molding with fast cavity surface temperature evolution

DEFF Research Database (Denmark)

Speranzaa, Vito; Liparotia, Sara; Calaon, Matteo

2017-01-01

The production of polymeric components with functional structures in the micrometer and sub-micrometer range is a complex challenge for the injection molding process, since it suffers the use of low cavity surface temperatures that induce the fast formation of a frozen layer, thus preventing...... was sufficient to obtain accurate replication, with adequate surface temperatures. In the case of nano-features, the replication accuracy was affected by the morphology developed on the molding surface, that is aligned along the flow direction with dimensions comparable with the dimension of the nano...

MaxAlign: maximizing usable data in an alignment

DEFF Research Database (Denmark)

Oliveira, Rodrigo Gouveia; Sackett, Peter Wad; Pedersen, Anders Gorm

2007-01-01

Align. In this paper we also introduce a new simple measure of tree similarity, Normalized Symmetric Similarity (NSS) that we consider useful for comparing tree topologies. CONCLUSION: We demonstrate how MaxAlign is helpful in detecting misaligned or defective sequences without requiring manual inspection. We also...

Chronic hypoxia suppresses the CO2 response of solitary complex (SC) neurons from rats.

Science.gov (United States)

Nichols, Nicole L; Wilkinson, Katherine A; Powell, Frank L; Dean, Jay B; Putnam, Robert W

2009-09-30

We studied the effect of chronic hypobaric hypoxia (CHx; 10-11% O(2)) on the response to hypercapnia (15% CO(2)) of individual solitary complex (SC) neurons from adult rats. We simultaneously measured the intracellular pH and firing rate responses to hypercapnia of SC neurons in superfused medullary slices from control and CHx-adapted adult rats using the blind whole cell patch clamp technique and fluorescence imaging microscopy. We found that CHx caused the percentage of SC neurons inhibited by hypercapnia to significantly increase from about 10% up to about 30%, but did not significantly alter the percentage of SC neurons activated by hypercapnia (50% in control vs. 35% in CHx). Further, the magnitudes of the responses of SC neurons from control rats (chemosensitivity index for activated neurons of 166+/-11% and for inhibited neurons of 45+/-15%) were the same in SC neurons from CHx-adapted rats. This plasticity induced in chemosensitive SC neurons by CHx appears to involve intrinsic changes in neuronal properties since they were the same in synaptic blockade medium.

Optically coupled cavities for wavelength switching

Energy Technology Data Exchange (ETDEWEB)

Costazo-Caso, Pablo A; Granieri, Sergio; Siahmakoun, Azad, E-mail: pcostanzo@ing.unlp.edu.ar, E-mail: granieri@rose-hulman.edu, E-mail: siahmako@rose-hulman.edu [Department of Physics and Optical Engineering, Rose-Hulman Institute of Technology, 5500 Wabash Avenue, Terre Haute, IN 47803 (United States)

2011-01-01

An optical bistable device which presents hysteresis behavior is proposed and experimentally demonstrated. The system finds applications in wavelength switching, pulse reshaping and optical bistability. It is based on two optically coupled cavities named master and slave. Each cavity includes a semiconductor optical amplifier (SOA), acting as the gain medium of the laser, and two pair of fiber Bragg gratings (FBG) which define the lasing wavelength (being different in each cavity). Finally, a variable optical coupler (VOC) is employed to couple both cavities. Experimental characterization of the system performance is made analyzing the effects of the coupling coefficient between the two cavities and the driving current in each SOA. The properties of the hysteretic bistable curve and switching can be controlled by adjusting these parameters and the loss in the cavities. By selecting the output wavelength ({lambda}{sub 1} or {lambda}{sub 2}) with an external filter it is possible to choose either the invert or non-invert switched signal. Experiments were developed employing both optical discrete components and a photonic integrated circuit. They show that for 8 m-long cavities the maximum switching frequency is about 500 KHz, and for 4 m-long cavities a minimum rise-time about 21 ns was measured. The switching time can be reduced by shortening the cavity lengths and using photonic integrated circuits.

Radio frequency superconductivity at CERN: a status report

International Nuclear Information System (INIS)

Arnolds-Mayer, G.; Benvenuti, C.; Bernard, P.

1988-01-01

Up to 1984 the efforts in superconducting (s.c.) cavity development at CERN were mainly concentrated on 500 MHz cavities, leading to the test of a 5-cell, 500 MHz cavity at PETRA. The results confirmed that the achievable accelerating fields do not decrease at lower frequencies as strongly as previously suspected. Therefore, it was decided in 1984 to concentrate efforts on 352 MHz cavities. This frequency choice is suggested by the fact that LEP will be equipped at the beginning with 128 Cu cavities at 352 MHz which will bring up energies to 55 GeV/beam [5]. There is an obvious interest to install at a later stage s.c. cavities with the same frequency and to use at maximum the existing installation of radio frequency (r.f.) power sources. With the installed r.f. power of 16 MW, LEP could be upgraded to ∼ 90 GeV by using s.c. cavities. This will require the construction, testing and installation of several hundred of s.c. cavities, therefore arguments of economy and reliability are of outstanding importance. The LEP program asks for many additional items and substantial work has gone into the development, construction and testing of cryostats, main couplers, Higher-Order Mode (HOM) couplers and frequency tuners. Besides the main line based on Nb-cavities another development has been pursued and that is the deposition of a thin niobium layer on copper cavities. Results look very promising but more efforts will be needed to reach the same level of know-how as for Nb cavities. 34 references, 7 figures, 2 tables

Aligning for Innovation - Alignment Strategy to Drive Innovation

Science.gov (United States)

Johnson, Hurel; Teltschik, David; Bussey, Horace, Jr.; Moy, James

2010-01-01

With the sudden need for innovation that will help the country achieve its long-term space exploration objectives, the question of whether NASA is aligned effectively to drive the innovation that it so desperately needs to take space exploration to the next level should be entertained. Authors such as Robert Kaplan and David North have noted that companies that use a formal system for implementing strategy consistently outperform their peers. They have outlined a six-stage management systems model for implementing strategy, which includes the aligning of the organization towards its objectives. This involves the alignment of the organization from the top down. This presentation will explore the impacts of existing U.S. industrial policy on technological innovation; assess the current NASA organizational alignment and its impacts on driving technological innovation; and finally suggest an alternative approach that may drive the innovation needed to take the world to the next level of space exploration, with NASA truly leading the way.

Scheme for the implementation of a universal quantum cloning machine via cavity-assisted atomic collisions in cavity QED

International Nuclear Information System (INIS)

Zou Xubo; Pahlke, K.; Mathis, W.

2003-01-01

We propose a scheme to implement the 1→2 universal quantum cloning machine of Buzek and Hillery [Phys. Rev. A 54, 1844 (1996)] in the context of cavity QED. The scheme requires cavity-assisted collision processes between atoms, which cross through nonresonant cavity fields in the vacuum states. The cavity fields are only virtually excited to face the decoherence problem. That's why the requirements on the cavity quality factor can be loosened

LHC crab-cavity aspects and strategy

International Nuclear Information System (INIS)

Calaga, R.; Tomas, R.; Zimmermann, F.

2010-01-01

The 3rd LHC Crab Cavity workshop (LHC-CC09) took place at CERN in October 2009. It reviewed the current status and identified a clear strategy towards a future crab-cavity implementation. Following the success of crab cavities in KEK-B and the strong potential for luminosity gain and leveling, CERN will pursue crab crossing for the LHC upgrade. We present a summary and outcome of the variousworkshop sessions which have led to the LHC crab-cavity strategy, covering topics like layout, cavity design, integration, machine protection, and a potential validation test in the SPS.

Nuclear reactor cavity streaming shield

International Nuclear Information System (INIS)

Klotz, R.J.; Stephen, D.W.

1978-01-01

The upper portion of a nuclear reactor vessel supported in a concrete reactor cavity has a structure mounted below the top of the vessel between the outer vessel wall and the reactor cavity wall which contains hydrogenous material which will attenuate radiation streaming upward between vessel and the reactor cavity wall while preventing pressure buildup during a loss of coolant accident

Use of antifungal Saponin SC-2 of Solanum chrysotrichum for the ...

African Journals Online (AJOL)

Fungistatic and fungicidal activity of saponin SC-2 on Candida albicans and other Candida species, fluconazole and ketoconazole resistaent strains was demostrated. SC-2-associated ultrastructural alterations in several Candida species were observed. An exploratory clinical, randomized, double-blind, and controlled ...

Offline estimation of decay time for an optical cavity with a low pass filter cavity model.

Science.gov (United States)

Kallapur, Abhijit G; Boyson, Toby K; Petersen, Ian R; Harb, Charles C

2012-08-01

This Letter presents offline estimation results for the decay-time constant for an experimental Fabry-Perot optical cavity for cavity ring-down spectroscopy (CRDS). The cavity dynamics are modeled in terms of a low pass filter (LPF) with unity DC gain. This model is used by an extended Kalman filter (EKF) along with the recorded light intensity at the output of the cavity in order to estimate the decay-time constant. The estimation results using the LPF cavity model are compared to those obtained using the quadrature model for the cavity presented in previous work by Kallapur et al. The estimation process derived using the LPF model comprises two states as opposed to three states in the quadrature model. When considering the EKF, this means propagating two states and a (2×2) covariance matrix using the LPF model, as opposed to propagating three states and a (3×3) covariance matrix using the quadrature model. This gives the former model a computational advantage over the latter and leads to faster execution times for the corresponding EKF. It is shown in this Letter that the LPF model for the cavity with two filter states is computationally more efficient, converges faster, and is hence a more suitable method than the three-state quadrature model presented in previous work for real-time estimation of the decay-time constant for the cavity.

Cost-effective parallel optical interconnection module based on fully passive-alignment process

Science.gov (United States)

Son, Dong Hoon; Heo, Young Soon; Park, Hyoung-Jun; Kang, Hyun Seo; Kim, Sung Chang

2017-11-01

In optical interconnection technology, high-speed and large data transitions with low error rate and cost reduction are key issues for the upcoming 8K media era. The researchers present notable types of optical manufacturing structures of a four-channel parallel optical module by fully passive alignment, which are able to reduce manufacturing time and cost. Each of the components, such as vertical-cavity surface laser/positive-intrinsic negative-photodiode array, microlens array, fiber array, and receiver (RX)/transmitter (TX) integrated circuit, is integrated successfully using flip-chip bonding, die bonding, and passive alignment with a microscope. Clear eye diagrams are obtained by 25.78-Gb/s (for TX) and 25.7-Gb/s (for RX) nonreturn-to-zero signals of pseudorandom binary sequence with a pattern length of 231 to 1. The measured responsivity and minimum sensitivity of the RX are about 0.5 A/W and ≤-6.5 dBm at a bit error rate (BER) of 10-12, respectively. The optical power margin at a BER of 10-12 is 7.5 dB, and cross talk by the adjacent channel is ≤1 dB.

Control rod housing alignment

International Nuclear Information System (INIS)

Dixon, R.C.; Deaver, G.A.; Punches, J.R.; Singleton, G.E.; Erbes, J.G.; Offer, H.P.

1990-01-01

This patent describes a process for measuring the vertical alignment between a hole in a core plate and the top of a corresponding control rod drive housing within a boiling water reactor. It comprises: providing an alignment apparatus. The alignment apparatus including a lower end for fitting to the top of the control rod drive housing; an upper end for fitting to the aperture in the core plate, and a leveling means attached to the alignment apparatus to read out the difference in angularity with respect to gravity, and alignment pin registering means for registering to the alignment pin on the core plate; lowering the alignment device on a depending support through a lattice position in the top guide through the hole in the core plate down into registered contact with the top of the control rod drive housing; registering the upper end to the sides of the hole in the core plate; registering the alignment pin registering means to an alignment pin on the core plate to impart to the alignment device the required angularity; and reading out the angle of the control rod drive housing with respect to the hole in the core plate through the leveling devices whereby the angularity of the top of the control rod drive housing with respect to the hole in the core plate can be determined

MUON DETECTORS: ALIGNMENT

CERN Multimedia

G. Gomez

2012-01-01

  A new muon alignment has been produced for 2012 A+B data reconstruction. It uses the latest Tracker alignment and single-muon data samples to align both DTs and CSCs. Physics validation has been performed and shows a modest improvement in stand-alone muon momentum resolution in the barrel, where the alignment is essentially unchanged from the previous version. The reference-target track-based algorithm using only collision muons is employed for the first time to align the CSCs, and a substantial improvement in resolution is observed in the endcap and overlap regions for stand-alone muons. This new alignment is undergoing the approval process and is expected to be deployed as part of a new global tag in the beginning of December. The pT dependence of the φ-bias in curvature observed in Monte Carlo was traced to a relative vertical misalignment between the Tracker and barrel muon systems. Moving the barrel as a whole to match the Tracker cures this pT dependence, leaving only the &phi...

Design of half-reentrant SRF cavities

International Nuclear Information System (INIS)

Meidlinger, M.; Grimm, T.L.; Hartung, W.

2006-01-01

The shape of a TeSLA inner cell can be improved to lower the peak surface magnetic field at the expense of a higher peak surface electric field by making the cell reentrant. Such a single-cell cavity was designed and tested at Cornell, setting a world record accelerating gradient [V. Shemelin et al., An optimized shape cavity for TESLA: concept and fabrication, 11th Workshop on RF Superconductivity, Travemuende, Germany, September 8-12, 2003; R. Geng, H. Padamsee, Reentrant cavity and first test result, Pushing the Limits of RF Superconductivity Workshop, Argonne National Laboratory, September 22-24, 2004]. However, the disadvantage to a cavity is that liquids become trapped in the reentrant portion when it is vertically hung during high pressure rinsing. While this was overcome for Cornell's single-cell cavity by flipping it several times between high pressure rinse cycles, this may not be feasible for a multi-cell cavity. One solution to this problem is to make the cavity reentrant on only one side, leaving the opposite wall angle at six degrees for fluid drainage. This idea was first presented in 2004 [T.L. Grimm et al., IEEE Transactions on Applied Superconductivity 15(6) (2005) 2393]. Preliminary designs of two new half-reentrant (HR) inner cells have since been completed, one at a high cell-to-cell coupling of 2.1% (high-k cc HR) and the other at 1.5% (low-k cc HR). The parameters of a HR cavity are comparable to a fully reentrant cavity, with the added benefit that a HR cavity can be easily cleaned with current technology

Simulation of beamline alignment operations

International Nuclear Information System (INIS)

Annese, C; Miller, M G.

1999-01-01

The CORBA-based Simulator was a Laboratory Directed Research and Development (LDRD) project that applied simulation techniques to explore critical questions about distributed control systems. The simulator project used a three-prong approach that studied object-oriented distribution tools, computer network modeling, and simulation of key control system scenarios. The National Ignition Facility's (NIF) optical alignment system was modeled to study control system operations. The alignment of NIF's 192 beamlines is a large complex operation involving more than 100 computer systems and 8000 mechanized devices. The alignment process is defined by a detailed set of procedures; however, many of the steps are deterministic. The alignment steps for a poorly aligned component are similar to that of a nearly aligned component; however, additional operations/iterations are required to complete the process. Thus, the same alignment operations will require variable amounts of time to perform depending on the current alignment condition as well as other factors. Simulation of the alignment process is necessary to understand beamline alignment time requirements and how shared resources such as the Output Sensor and Target Alignment Sensor effect alignment efficiency. The simulation has provided alignment time estimates and other results based on documented alignment procedures and alignment experience gained in the laboratory. Computer communication time, mechanical hardware actuation times, image processing algorithm execution times, etc. have been experimentally determined and incorporated into the model. Previous analysis of alignment operations utilized average implementation times for all alignment operations. Resource sharing becomes rather simple to model when only average values are used. The time required to actually implement the many individual alignment operations will be quite dynamic. The simulation model estimates the time to complete an operation using

CAB-Align: A Flexible Protein Structure Alignment Method Based on the Residue-Residue Contact Area.

Directory of Open Access Journals (Sweden)

Genki Terashi

Full Text Available Proteins are flexible, and this flexibility has an essential functional role. Flexibility can be observed in loop regions, rearrangements between secondary structure elements, and conformational changes between entire domains. However, most protein structure alignment methods treat protein structures as rigid bodies. Thus, these methods fail to identify the equivalences of residue pairs in regions with flexibility. In this study, we considered that the evolutionary relationship between proteins corresponds directly to the residue-residue physical contacts rather than the three-dimensional (3D coordinates of proteins. Thus, we developed a new protein structure alignment method, contact area-based alignment (CAB-align, which uses the residue-residue contact area to identify regions of similarity. The main purpose of CAB-align is to identify homologous relationships at the residue level between related protein structures. The CAB-align procedure comprises two main steps: First, a rigid-body alignment method based on local and global 3D structure superposition is employed to generate a sufficient number of initial alignments. Then, iterative dynamic programming is executed to find the optimal alignment. We evaluated the performance and advantages of CAB-align based on four main points: (1 agreement with the gold standard alignment, (2 alignment quality based on an evolutionary relationship without 3D coordinate superposition, (3 consistency of the multiple alignments, and (4 classification agreement with the gold standard classification. Comparisons of CAB-align with other state-of-the-art protein structure alignment methods (TM-align, FATCAT, and DaliLite using our benchmark dataset showed that CAB-align performed robustly in obtaining high-quality alignments and generating consistent multiple alignments with high coverage and accuracy rates, and it performed extremely well when discriminating between homologous and nonhomologous pairs of proteins

CAB-Align: A Flexible Protein Structure Alignment Method Based on the Residue-Residue Contact Area.

Science.gov (United States)

Terashi, Genki; Takeda-Shitaka, Mayuko

2015-01-01

Proteins are flexible, and this flexibility has an essential functional role. Flexibility can be observed in loop regions, rearrangements between secondary structure elements, and conformational changes between entire domains. However, most protein structure alignment methods treat protein structures as rigid bodies. Thus, these methods fail to identify the equivalences of residue pairs in regions with flexibility. In this study, we considered that the evolutionary relationship between proteins corresponds directly to the residue-residue physical contacts rather than the three-dimensional (3D) coordinates of proteins. Thus, we developed a new protein structure alignment method, contact area-based alignment (CAB-align), which uses the residue-residue contact area to identify regions of similarity. The main purpose of CAB-align is to identify homologous relationships at the residue level between related protein structures. The CAB-align procedure comprises two main steps: First, a rigid-body alignment method based on local and global 3D structure superposition is employed to generate a sufficient number of initial alignments. Then, iterative dynamic programming is executed to find the optimal alignment. We evaluated the performance and advantages of CAB-align based on four main points: (1) agreement with the gold standard alignment, (2) alignment quality based on an evolutionary relationship without 3D coordinate superposition, (3) consistency of the multiple alignments, and (4) classification agreement with the gold standard classification. Comparisons of CAB-align with other state-of-the-art protein structure alignment methods (TM-align, FATCAT, and DaliLite) using our benchmark dataset showed that CAB-align performed robustly in obtaining high-quality alignments and generating consistent multiple alignments with high coverage and accuracy rates, and it performed extremely well when discriminating between homologous and nonhomologous pairs of proteins in both

Assembly Test of Elastic Averaging Technique to Improve Mechanical Alignment for Accelerating Structure Assemblies in CLIC

CERN Document Server

Huopana, J

2010-01-01

The CLIC (Compact LInear Collider) is being studied at CERN as a potential multi-TeV e+e- collider [1]. The manufacturing and assembly tolerances for the required RF-components are important for the final efficiency and for the operation of CLIC. The proper function of an accelerating structure is very sensitive to errors in shape and location of the accelerating cavity. This causes considerable issues in the field of mechanical design and manufacturing. Currently the design of the accelerating structures is a disk design. Alternatively it is possible to create the accelerating assembly from quadrants, which favour the mass manufacturing. The functional shape inside of the accelerating structure remains the same and a single assembly uses less parts. The alignment of these quadrants has been previously made kinematic by using steel pins or spheres to align the pieces together. This method proved to be a quite tedious and time consuming method of assembly. To limit the number of different error sources, a meth...

The role of the bimodal distribution of ultra-fine silicon phase and nano-scale V-phase (AlSi2Sc2) on spark plasma sintered hypereutectic Al–Si–Sc alloys

International Nuclear Information System (INIS)

Raghukiran, Nadimpalli; Kumar, Ravi

2016-01-01

Hypereutectic Al–Si and Al–Si–Sc alloys were spark plasma sintered from corresponding gas-atomized powders. The microstructures of the Al–Si and Al–Si–Sc alloys possessed remarkably refined silicon particles in the size range of 0.38–3.5 µm and 0.35–1.16 µm respectively in contrast to the silicon particles of size greater than 100 µm typically found in conventionally cast alloys. All the sintered alloys exhibited significant ductility of as high as 85% compressive strain without failure even with the presence of relatively higher weight fraction of the brittle silicon phase. Moreover, the Al–Si–Sc alloys have shown appreciable improvement in the compressive strength over their binary counterparts due to the presence of intermetallic compound AlSi 2 Sc 2 of size 10–20 nm distributed uniformly in the matrix of those alloys. The dry sliding pin-on-disc wear tests showed improvement in the wear performance of the sintered alloys with increase in silicon content in the alloys. Further, the Al–Si–Sc ternary alloys with relatively lesser silicon content exhibited appreciable improvement in the wear resistance over their binary counterparts. The Al–Si–Sc alloys with bimodal distribution of the strengthening phases consisting of ultra-fine (sub-micron size) silicon particles and the nano-scale AlSi 2 Sc 2 improved the strength and wear properties of the alloys while retaining significant amount of ductility.

BinAligner: a heuristic method to align biological networks.

Science.gov (United States)

Yang, Jialiang; Li, Jun; Grünewald, Stefan; Wan, Xiu-Feng

2013-01-01

The advances in high throughput omics technologies have made it possible to characterize molecular interactions within and across various species. Alignments and comparison of molecular networks across species will help detect orthologs and conserved functional modules and provide insights on the evolutionary relationships of the compared species. However, such analyses are not trivial due to the complexity of network and high computational cost. Here we develop a mixture of global and local algorithm, BinAligner, for network alignments. Based on the hypotheses that the similarity between two vertices across networks would be context dependent and that the information from the edges and the structures of subnetworks can be more informative than vertices alone, two scoring schema, 1-neighborhood subnetwork and graphlet, were introduced to derive the scoring matrices between networks, besides the commonly used scoring scheme from vertices. Then the alignment problem is formulated as an assignment problem, which is solved by the combinatorial optimization algorithm, such as the Hungarian method. The proposed algorithm was applied and validated in aligning the protein-protein interaction network of Kaposi's sarcoma associated herpesvirus (KSHV) and that of varicella zoster virus (VZV). Interestingly, we identified several putative functional orthologous proteins with similar functions but very low sequence similarity between the two viruses. For example, KSHV open reading frame 56 (ORF56) and VZV ORF55 are helicase-primase subunits with sequence identity 14.6%, and KSHV ORF75 and VZV ORF44 are tegument proteins with sequence identity 15.3%. These functional pairs can not be identified if one restricts the alignment into orthologous protein pairs. In addition, BinAligner identified a conserved pathway between two viruses, which consists of 7 orthologous protein pairs and these proteins are connected by conserved links. This pathway might be crucial for virus packing and

Prediction of molecular alignment of nucleic acids in aligned media

International Nuclear Information System (INIS)

Wu Bin; Petersen, Michael; Girard, Frederic; Tessari, Marco; Wijmenga, Sybren S.

2006-01-01

We demonstrate - using the data base of all deposited DNA and RNA structures aligned in Pf1-medium and RDC refined - that for nucleic acids in a Pf1-medium the electrostatic alignment tensor can be predicted reliably and accurately via a simple and fast calculation based on the gyration tensor spanned out by the phosphodiester atoms. The rhombicity is well predicted over its full range from 0 to 0.66, while the alignment tensor orientation is predicted correctly for rhombicities up to ca. 0.4, for larger rhombicities it appears to deviate somewhat more than expected based on structural noise and measurement error. This simple analytical approach is based on the Debye-Huckel approximation for the electrostatic interaction potential, valid at distances sufficiently far away from a poly-ionic charged surface, a condition naturally enforced when the charge of alignment medium and solute are of equal sign, as for nucleic acids in a Pf1-phage medium. For the usual salt strengths and nucleic acid sizes, the Debye-Huckel screening length is smaller than the nucleic acid size, but large enough for the collective of Debye-Huckel spheres to encompass the whole molecule. The molecular alignment is then purely electrostatic, but it's functional form is under these conditions similar to that for steric alignment. The proposed analytical expression allows for very fast calculation of the alignment tensor and hence RDCs from the conformation of the nucleic acid molecule. This information provides opportunities for improved structure determination of nucleic acids, including better assessment of dynamics in (multi-domain) nucleic acids and the possibility to incorporate alignment tensor prediction from shape directly into the structure calculation process. The procedures are incorporated into MATLAB scripts, which are available on request

Magnet measuring equipment of SC2

CERN Multimedia

CERN PhotoLab

1974-01-01

Checking the positioning of the magnet measuring equipment installed between the poles of SC2. The steel structure in front of the magnet is designed to house the rotary condenser and to shield it from the stray magnetic field of the accelerator.

Particle acceleration and wave emissions associated with the formation of auroral cavities and enhancements

International Nuclear Information System (INIS)

Winglee, R.M.; Pritchett, P.L.; Dusenbery, P.B.

1988-01-01

Observations from DE 1 and electrostatic particle simulations are combined in an effort to provide a unified model for (nightside) auroral particle acceleration and wave emissions and their association with plasma cavities and enhancements. The observations show that enhanced electron precipitation during inverted-V events is associated with broadband electrostatic bursts (BEB), increased upward field-aligned currents, and density enhancements. These regions are flanked by return current regions where the density is depleted (i.e., by plasma cavities). Perpendicular acceleration of ambient plasma ions can occur in both upward and return current regions. It is shown through the simulations that these processes are integrally related and are not independent of each other. The free energy for the auroral particle acceleration can be provided by energetic ion beams in the plasma sheet boundary layer with nonzero perpendicular energy. The perpendicular energy allows charge separation between the beam ions and costreaming electrons to occur. The resultant space charge fields accelerate electrons on the same field lines as the costreaming electrons downward toward the ionosphere, without the beam ions actually propagating down to auroral altitudes. Ambient plasma electrons on adjacent field lines are accelerated upward, forming a return current

Phase equilibria in the system Li2O - MoO3 - Sc2O3

International Nuclear Information System (INIS)

Safonov, V.V.; Chaban, N.G.; Porotnikov, N.V.

1984-01-01

Using the methods of DTA and X-ray phase analysis, interaction of components in the system Li 2 O-MoO 3 -Sc 2 O 3 in concentration range, adjacent to the vertex of MoO 3 , has been studied. Projection of the Li 2 MoO 4 -MoO 3 -Sc 2 (MoO 4 ) 3 system liquidus on concentrational triangle of the compositions Li 2 O-MoO 3 -Sc 2 O 3 , which consists of the fields of primary separation of Li 2 MoO 4 , Li 2 Mo 5 O 17 , Li 2 Mo 4 O 13 , MoO 3 , Sc 2 (MoO 4 ) 3 , Li 3 Sc(MoO 4 ) 3 and LiSc(MoO 4 ) 2 , is built

Laser Oscillator Incorporating a Wedged Polarization Rotator and a Porro Prism as Cavity Mirror

Science.gov (United States)

Li, Steven

2011-01-01

A laser cavity was designed and implemented by using a wedged polarization rotator and a Porro prism in order to reduce the parts count, and to improve the laser reliability. In this invention, a z-cut quartz polarization rotator is used to compensate the wavelength retardance introduced by the Porro prism. The polarization rotator rotates the polarization of the linear polarized beam with a designed angle that is independent of the orientation of the rotator. This unique property was used to combine the retardance compensation and a Risley prism to a single optical component: a wedged polarization rotator. This greatly simplifies the laser alignment procedure and reduces the number of the laser optical components.

Optical cavity furnace for semiconductor wafer processing

Science.gov (United States)

Sopori, Bhushan L.

2014-08-05

An optical cavity furnace 10 having multiple optical energy sources 12 associated with an optical cavity 18 of the furnace. The multiple optical energy sources 12 may be lamps or other devices suitable for producing an appropriate level of optical energy. The optical cavity furnace 10 may also include one or more reflectors 14 and one or more walls 16 associated with the optical energy sources 12 such that the reflectors 14 and walls 16 define the optical cavity 18. The walls 16 may have any desired configuration or shape to enhance operation of the furnace as an optical cavity 18. The optical energy sources 12 may be positioned at any location with respect to the reflectors 14 and walls defining the optical cavity. The optical cavity furnace 10 may further include a semiconductor wafer transport system 22 for transporting one or more semiconductor wafers 20 through the optical cavity.

Tuned optical cavity magnetometer

Science.gov (United States)

Okandan, Murat; Schwindt, Peter

2010-11-02

An atomic magnetometer is disclosed which utilizes an optical cavity formed from a grating and a mirror, with a vapor cell containing an alkali metal vapor located inside the optical cavity. Lasers are used to magnetically polarize the alkali metal vapor and to probe the vapor and generate a diffracted laser beam which can be used to sense a magnetic field. Electrostatic actuators can be used in the magnetometer for positioning of the mirror, or for modulation thereof. Another optical cavity can also be formed from the mirror and a second grating for sensing, adjusting, or stabilizing the position of the mirror.

LHCb Data Replication During SC3

CERN Multimedia

Smith, A

2006-01-01

LHCb's participation in LCG's Service Challenge 3 involves testing the bulk data transfer infrastructure developed to allow high bandwidth distribution of data across the grid in accordance with the computing model. To enable reliable bulk replication of data, LHCb's DIRAC system has been integrated with gLite's File Transfer Service middleware component to make use of dedicated network links between LHCb computing centres. DIRAC's Data Management tools previously allowed the replication, registration and deletion of files on the grid. For SC3 supplementary functionality has been added to allow bulk replication of data (using FTS) and efficient mass registration to the LFC replica catalog.Provisional performance results have shown that the system developed can meet the expected data replication rate required by the computing model in 2007. This paper details the experience and results of integration and utilisation of DIRAC with the SC3 transfer machinery.

Mise en scène ja kertova lavastus

OpenAIRE

Bruun, Ida

2013-01-01

Tämä opinnäytetyö tutkii mise en scèneä ja lavastuksen kerronnallista vaikutusta elokuvassa. Työ on toteutettu toiminnallisena ja koostuu kirjallisesta osasta ja teososasta. Teososa on vuonna 2012 ensi-iltansa saanut fiktiivinen lyhytelokuva Varjelus. Toimin elokuvassa lavastajana ja rekvisitöörinä. Kirjallinen osuus alkaa käsittelemällä mise en scènen, eli ’näyttämöllepanon’ määritelmää ja sen syntyä elokuvalliseksi konseptiksi. Työ etenee esittelemään ja tarkastelemaan käsitteen eri vis...

Phonon and thermodynamical properties of CuSc: A DFT study

Science.gov (United States)

Jain, Ekta; Pagare, Gitanjali; Dubey, Shubha; Sanyal, S. P.

2018-05-01

A detailed systematic theoretical investigation of phonon and thermodynamical behavior of CuSc intermetallic compound has been carried out by uing first-principles density functional theory in B2-type (CsCl) crystal structure. Phonon dispersion curve and phonon density of states (PhDOS) are studied which confirm the stability of CuSc intermetallic compound in B2 phase. It is found that PhDOS at high frequencies mostly composed of Sc states. We have also presented some temperature dependent properties such as entropy, free energy, heat capacity, internal energy and thermal displacement, which are computed under PHONON code. The various features of these quantities are discussed in detail. From these results we demonstrate that the particular intermetallic have better ductility and larger thermal expansion.

Original Research: Use of hydroxyurea and phlebotomy in pediatric patients with hemoglobin SC disease

OpenAIRE

Summarell, Carly C Ginter; Sheehan, Vivien A

2016-01-01

Hydroxyurea is an excellent therapeutic agent for the pharmacological induction of HbF in patients with sickle cell disease (SCD). However, all completed clinical trials of hydroxyurea have excluded patients with hemoglobin SC (HbSC) disease. HbSC differs significantly in pathophysiology from HbSS, as HbC does not sickle, but instead causes cellular dehydration which potentiates sickling of HbS. Many severely affected HbSC patients have been placed on hydroxyurea on a case by case basis, but ...

Inter-assemblage facilitation: the functional diversity of cavity-producing beetles drives the size diversity of cavity-nesting bees.

Science.gov (United States)

Sydenham, Markus A K; Häusler, Lise D; Moe, Stein R; Eldegard, Katrine

2016-01-01

Inter-specific interactions are important drivers and maintainers of biodiversity. Compared to trophic and competitive interactions, the role of non-trophic facilitation among species has received less attention. Cavity-nesting bees nest in old beetle borings in dead wood, with restricted diameters corresponding to the body size of the bee species. The aim of this study was to test the hypothesis that the functional diversity of cavity-producing wood boring beetles - in terms of cavity diameters - drives the size diversity of cavity-nesting bees. The invertebrate communities were sampled in 30 sites, located in forested landscapes along an elevational gradient. We regressed the species richness and abundance of cavity nesting bees against the species richness and abundance of wood boring beetles, non-wood boring beetles and elevation. The proportion of cavity nesting bees in bee species assemblage was regressed against the species richness and abundance of wood boring beetles. We also tested the relationships between the size diversity of cavity nesting bees and wood boring beetles. The species richness and abundance of cavity nesting bees increased with the species richness and abundance of wood boring beetles. No such relationship was found for non-wood boring beetles. The abundance of wood boring beetles was also related to an increased proportion of cavity nesting bee individuals. Moreover, the size diversity of cavity-nesting bees increased with the functional diversity of wood boring beetles. Specifically, the mean and dispersion of bee body sizes increased with the functional dispersion of large wood boring beetles. The positive relationships between cavity producing bees and cavity nesting bees suggest that non-trophic facilitative interactions between species assemblages play important roles in organizing bee species assemblages. Considering a community-wide approach may therefore be required if we are to successfully understand and conserve wild bee

Discrete vapour cavity model with improved timing of opening and collapse of cavities

NARCIS (Netherlands)

Bergant, A.; Tijsseling, A.S.; Vítkovský, J.P.; Simpson, A.R.; Lambert, M.F.

2007-01-01

Transient vaporous cavitation occurs in hydraulic piping systems when the liquid pressure falls to the vapour pressure. Cavitation may occur as a localized vapour cavity (large void fraction) or as distributed vaporous cavitation (small void fraction). The discrete vapour cavity model (DVCM) with

First-principles study of the nucleation and stability of ordered precipitates in ternary Al-Sc-Li alloys

International Nuclear Information System (INIS)

Mao, Z.; Chen, W.; Seidman, D.N.; Wolverton, C.

2011-01-01

First-principles density functional calculations are used to study the nucleation and stability of L1 2 -ordered precipitates in Al-Sc-Li alloys. For dilute Al alloys, there are three possible ordered L1 2 precipitates: Al 3 Sc, Al 3 Li and an Al 3 Sc/Al 3 Li core/shell structure. To calculate the nucleation behavior, information about bulk thermodynamics (both static total energies and vibrational free energies), interfacial energetics and coherency strain is required. The study finds the following: (1) the coherency strain energies for forming coherent interfaces between Al/Al 3 Sc, Al/Al 3 Li and Al 3 Sc/Al 3 Li are relatively small, owing to the small atomic size mismatches in these systems; (2) the sublattice site preferences of Sc and Li are calculated, and it is demonstrated that Sc and Li share the same sublattice sites in both Al 3 Sc(L1 2 ) and Al 3 Li(L1 2 ), in agreement with recent experimental results; (3) the calculated solubilities of Sc and Li in α-Al alloys are in good agreement with experimental values and, for Sc, agree well with prior first-principles results; (4) the interfacial energies for Al/Al 3 Sc, Al/Al 3 Li and Al 3 Sc/Al 3 Li for (1 0 0), (1 1 0) and (1 1 1) interfaces are calculated: the values of the Al/Al 3 Sc interfacial energies are significantly larger than those of the Al/Al 3 Li and Al 3 Sc/Al 3 Li interfaces; (5) combining the bulk and interfacial energies yields the nucleation barriers and critical radii for Al 3 Sc and Al 3 Li precipitates; and (6) the energetic stability of the Al 3 Sc/Al 3 Li core/shell structure is compared with individual Al 3 Sc and Al 3 Li nuclei, and the range of precipitate sizes for which the core/shell structure is energetically favored is determined quantitatively.

A new prosthetic alignment device to read and record prosthesis alignment data.

Science.gov (United States)

Pirouzi, Gholamhossein; Abu Osman, Noor Azuan; Ali, Sadeeq; Davoodi Makinejad, Majid

2017-12-01

Prosthetic alignment is an essential process to rehabilitate patients with amputations. This study presents, for the first time, an invented device to read and record prosthesis alignment data. The digital device consists of seven main parts: the trigger, internal shaft, shell, sensor adjustment button, digital display, sliding shell, and tip. The alignment data were read and recorded by the user or a computer to replicate prosthesis adjustment for future use or examine the sequence of changes in alignment and its effect on the posture of the patient. Alignment data were recorded at the anterior/posterior and medial/lateral positions for five patients. Results show the high level of confidence to record alignment data and replicate adjustments. Therefore, the device helps patients readjust their prosthesis by themselves, or prosthetists to perform adjustment for patients and analyze the effects of malalignment.

Conduction cooling systems for linear accelerator cavities

Science.gov (United States)

Kephart, Robert

2017-05-02

A conduction cooling system for linear accelerator cavities. The system conducts heat from the cavities to a refrigeration unit using at least one cavity cooler interconnected with a cooling connector. The cavity cooler and cooling connector are both made from solid material having a very high thermal conductivity of approximately 1.times.10.sup.4 W m.sup.-1 K.sup.-1 at temperatures of approximately 4 degrees K. This allows for very simple and effective conduction of waste heat from the linear accelerator cavities to the cavity cooler, along the cooling connector, and thence to the refrigeration unit.

Pacer processing: cavity inventory relationships

International Nuclear Information System (INIS)

Dietz, R.J.; Gritzo, L.A.

1975-09-01

The pacer cavity and its associated primary power loop comprise a recirculating system in which materials are introduced by a series of thermonuclear explosions while debris is continuously removed by radioactive decay, sorption phenomena, and deliberate processing. Safe, reliable, and economical realization of the Pacer concept depends on the removal and control of both noxious and valuable by-products of the fusion reaction. Mathematical relationships are developed that describe the quantities of materials that are introduced into the Pacer cavity by a series of discrete events and are removed continuously by processing and decay. An iterative computer program based on these relationships is developed that allows both the total cavity inventory and the amounts of important individual species to be determined at any time during the lifetime of the cavity in order to establish the effects of the thermonuclear event, the cavity, the flow, and various processing parameters on Pacer design requirements

Design of SC solenoid with high homogeneity

International Nuclear Information System (INIS)

Yang Xiaoliang; Liu Zhong; Luo Min; Luo Guangyao; Kang Qiang; Tan Jie; Wu Wei

2014-01-01

A novel kind of SC (superconducting) solenoid coil is designed to satisfy the homogeneity requirement of the magnetic field. In this paper, we first calculate the current density distribution of the solenoid coil section through the linear programming method. Then a traditional solenoid and a nonrectangular section solenoid are designed to produce a central field up to 7 T with a homogeneity to the greatest extent. After comparison of the two solenoid coils designed in magnet field quality, fabrication cost and other aspects, the new design of the nonrectangular section of a solenoid coil can be realized through improving the techniques of framework fabrication and winding. Finally, the outlook and error analysis of this kind of SC magnet coil are also discussed briefly. (authors)

Continuous-wave cavity ringdown spectroscopy based on the control of cavity reflection.

Science.gov (United States)

Li, Zhixin; Ma, Weiguang; Fu, Xiaofang; Tan, Wei; Zhao, Gang; Dong, Lei; Zhang, Lei; Yin, Wangbao; Jia, Suotang

2013-07-29

A new type of continuous-wave cavity ringdown spectrometer based on the control of cavity reflection for trace gas detection was designed and evaluated. The technique separated the acquisitions of the ringdown event and the trigger signal to optical switch by detecting the cavity reflection and transmission, respectively. A detailed description of the time sequence of the measurement process was presented. In order to avoid the wrong extraction of ringdown time encountered accidentally in fitting procedure, the laser frequency and cavity length were scanned synchronously. Based on the statistical analysis of measured ringdown times, the frequency normalized minimum detectable absorption in the reflection control mode was 1.7 × 10(-9)cm(-1)Hz(-1/2), which was 5.4 times smaller than that in the transmission control mode. However the signal-to-noise ratio of the absorption spectrum was only 3 times improved since the etalon effect existed. Finally, the peak absorption coefficients of the C(2)H(2) transition near 1530.9nm under different pressures showed a good agreement with the theoretical values.

Impregnated cathode coated with tungsten thin film containing Sc2O3

International Nuclear Information System (INIS)

Yamamoto, S.; Taguchi, S.; Watanabe, I.; Kawase, S.

1987-01-01

An impregnated cathode of a novel structure is proposed, fabricated, and evaluated. A thin tungsten film 100--400 nm in thickness containing various amounts of Sc 2 O 3 is coated on a standard impregnated cathode composed of a porous tungsten body in which electron emissive materials are impregnated. The electron emission property measured with a diode configuration is found to be dependent on Sc 2 O 3 content and surface atom distribution. Surface atom distribution is depicted by means of Auger electron spectroscopy. For high electron emission enhancement it is necessary for Sc 2 O 3 content to be 2.5--6.5 wt. % and for a layer of the order of a monolayer in thickness composed of Ba, Sc, and O to develop on the cathode surface

Effects of variable attachment shapes and aligner material on aligner retention.

Science.gov (United States)

Dasy, Hiltrud; Dasy, Andreas; Asatrian, Greg; Rózsa, Noémi; Lee, Hao-Fu; Kwak, Jin Hee

2015-11-01

To evaluate the retention of four types of aligners on a dental arch with various attachments. For this study, three casts were manufactured, two of which contained attachments (ellipsoid and beveled), and one without any attachments to serve as a control. Four types of aligners were thermoformed: Clear-Aligner (CA)-soft, CA-medium, and CA-hard, with various thicknesses, and Essix ACE. Measurements of vertical displacement force during aligner removal were performed with the Gabo Qualimeter Eplexor. Means and standard deviations were next compared between different aligner thicknesses and attachment shapes. CA-soft, CA-medium, and CA-hard did not present a significant increase in retention, except when used in the presence of attachments. Additionally, CA-medium and CA-hard required significantly more force for removal. Essix ACE demonstrated a significant decrease in retention when used with ellipsoid attachments. The force value for Essix ACE removal from the cast with beveled attachments was comparable to that of CA-medium. Forces for aligner removal from the model without attachments showed a linear trend. Essix ACE did not show a continuous increase in retention for each model. Overall, ellipsoid attachments did not present a significant change in retention. In contrast, beveled attachments improved retention. Ellipsoid attachments had no significant influence on the force required for aligner removal and hence on aligner retention. Essix ACE showed significantly less retention than CA-hard on the models with attachments. Furthermore, beveled attachments were observed to increase retention significantly, compared with ellipsoid attachments and when using no attachments.

Design of rf conditioner cavities

International Nuclear Information System (INIS)

Govil, R.; Rimmer, R.A.; Sessler, A.; Kirk, H.G.

1992-06-01

Theoretical studies are made of radio frequency structures which can be used to condition electron beams so as to greatly reduce the stringent emittance requirements for successful lasing in a free-electron laser. The basic strategy of conditioning calls for modulating an electron beam in the transverse dimension, by a periodic focusing channel, while it traverses a series of rf cavities, each operating in a TM 210 mode. In this paper, we analyze the cavities both analytically and numerically (using MAFIA simulations). We find that when cylindrical symmetry is broken the coupling impedance can be greatly enhanced. We present results showing various performance characteristics as a function of cavity parameters, as well as possible designs for conditioning cavities

Cavity QED with single trapped Ca+-ions

International Nuclear Information System (INIS)

Mundt, A.B.

2003-02-01

This thesis reports on the design and setup of a vacuum apparatus allowing the investigation of cavity QED effects with single trapped 40 Ca + ions. The weak coupling of ion and cavity in the 'bad cavity limit' may serve to inter--convert stationary and flying qubits. The ion is confined in a miniaturized Paul trap and cooled via the Doppler effect to the Lamb--Dicke regime. The extent of the atomic wave function is less than 30 nm. The ion is enclosed by a high finesse optical cavity. The technically--involved apparatus allows movement of the trap relative to the cavity and the trapped ion can be placed at any position in the standing wave. By means of a transfer lock the cavity can be resonantly stabilized with the S 1/2 ↔ D 5/2 quadrupole transition at 729 nm (suitable as a qubit) without light at that wavelength being present in the cavity. The coupling of the cavity field to the S 1/2 ↔ D 5/2 quadrupole transition is investigated with various techniques in order to determine the spatial dependence as well as the temporal dynamics. The orthogonal coupling of carrier and first--order sideband transitions at field nodes and antinodes is explored. The coherent interaction of the ion and the cavity field is confirmed by exciting Rabi oscillations with short resonant pulses injected into the cavity. Finally, first experimental steps towards the observation of cavity enhanced spontaneous emission have been taken. (author)

Differential dynamics of splicing factor SC35 during the cell cycle

Indian Academy of Sciences (India)

Fluorescence recovery after photobleaching (FRAP) experiments revealed that the mobility of GFP-SC35 was distinct in different mitotic compartments. Interestingly, the mobility of GFP-SC35 was 3-fold higher in the cytoplasm of metaphase cells compared with interphase speckles, the nucleoplasm or MIGs. Treatment of ...

BOOK REVIEW: Assessing Sc1 for GCSE

Science.gov (United States)

Reynolds, H.

2000-01-01

It is well known that investigations that `fit' the National Curriculum or examination board criteria are few in number. The fair testing emphasis means that pupils all over the country are finding out what affects the rate of a chemical reaction, the rate of photosynthesis or, in the case of Physics, the resistance of a wire. This book focuses on nine of the most common Sc1 investigations and how to prepare for them, manage and assess them. The author, a GCSE examiner, has turned his expertise into a handbook for improving Sc1 performance in the classroom. He has produced a book that would be extremely useful to both newly qualified teachers and experienced teachers. The first aim of the book, however, is to explain the requirements of Sc1. This is done comprehensively with examples of what the jargon means in practice. By breaking down the elements of planning, obtaining evidence, analysing evidence and evaluating, it is easy to see the subtleties of the mark descriptors. At first glance there seems to be little difference between the type of scientific knowledge needed for planning at level 6 and level 8. However, the level 8 statement specifies `detailed' scientific knowledge and understanding, which would mean a student should use equations from physics or symbolic chemical equations to support their arguments. One of the most useful sections in the book details the marking problems that can arise with some investigations. For example, in an investigation into electromagnets it is difficult for students to provide sufficient relevant scientific theory to satisfy the requirements of planning at level 6. One of the problems with Sc1 is that certain requirements, such as graph plotting, are difficult for many students. This book provides exercises that can be given to students to improve those skills. Each of the nine investigations is covered in great detail. Each investigation begins with an introduction detailing the rationale for choosing it, whether students

Voltage control of cavity magnon polariton

Energy Technology Data Exchange (ETDEWEB)

Kaur, S., E-mail: kaurs3@myumanitoba.ca; Rao, J. W.; Gui, Y. S.; Hu, C.-M., E-mail: hu@physics.umanitoba.ca [Department of Physics and Astronomy, University of Manitoba, Winnipeg, Manitoba R3T 2N2 (Canada); Yao, B. M. [Department of Physics and Astronomy, University of Manitoba, Winnipeg, Manitoba R3T 2N2 (Canada); National Laboratory for Infrared Physics, Chinese Academy of Sciences, Shanghai 200083 (China)

2016-07-18

We have experimentally investigated the microwave transmission of the cavity-magnon-polariton (CMP) generated by integrating a low damping magnetic insulator onto a 2D microwave cavity. The high tunability of our planar cavity allows the cavity resonance frequency to be precisely controlled using a DC voltage. By appropriately tuning the voltage and magnetic bias, we can observe the cavity photon magnon coupling and the magnetic coupling between a magnetostatic mode and the generated CMP. The dispersion of the generated CMP was measured by either tuning the magnetic field or the applied voltage. This electrical control of CMP may open up avenues for designing advanced on-chip microwave devices that utilize light-matter interaction.

Cavity pressure history of contained nuclear explosions

Energy Technology Data Exchange (ETDEWEB)

Chapin, C E [Lawrence Radiation Laboratory, University of California, Livermore, CA (United States)

1970-05-01

Knowledge of pressure in cavities created by contained nuclear explosions is useful for estimating the possibility of venting radioactive debris to the atmosphere. Measurements of cavity pressure, or temperature, would be helpful in evaluating the correctness of present code predictions of underground explosions. In instrumenting and interpreting such measurements it is necessary to have good theoretical estimates of cavity pressures. In this paper cavity pressure is estimated at the time when cavity growth is complete. Its subsequent decrease due to heat loss from the cavity to the surrounding media is also predicted. The starting pressure (the pressure at the end of cavity growth) is obtained by adiabatic expansion to the final cavity size of the vaporized rock gas sphere created by the explosion. Estimates of cavity size can be obtained by stress propagation computer codes, such as SOC and TENSOR. However, such estimates require considerable time and effort. In this paper, cavity size is estimated using a scheme involving simple hand calculations. The prediction is complicated by uncertainties in the knowledge of silica water system chemistry and a lack of information concerning possible blowoff of wall material during cavity growth. If wall material blows off, it can significantly change the water content in the cavity, compared to the water content in the ambient media. After cavity growth is complete, the pressure will change because of heat loss to the surrounding media. Heat transfer by convection, radiation and conduction is considered, and its effect on the pressure is calculated. Analysis of cavity heat transfer is made difficult by the complex nature of processes which occur at the wall where melting, vaporization and condensation of the gaseous rock can all occur. Furthermore, the melted wall material could be removed by flowing or dripping to the cavity floor. It could also be removed by expansion of the steam contained in the melt (blowoff) and by

44Sc-DOTA-BN[2-14]NH2 in comparison to 68Ga-DOTA-BN[2-14]NH2 in pre-clinical investigation. Is 44Sc a potential radionuclide for PET?

International Nuclear Information System (INIS)

Koumarianou, E.; Loktionova, N.S.; Fellner, M.; Roesch, F.; Thews, O.; Pawlak, D.; Archimandritis, S.C.; Mikolajczak, R.

2012-01-01

Aim: In the present study we demonstrate the in vitro and in vivo comparison of the 44 Sc and 68 Ga labeled DOTA-BN[2-14]NH 2 . 44 Sc is a positron emitter with a half life of 3.92 h. Hence it could be used for PET imaging with ligands requiring longer observation time than in the case of 68 Ga. Methods: The binding affinity of nat Sc-DOTA-BN[2-14]NH 2 and nat Ga-DOTA-BN[2-14]NH 2 to GRP receptors was studied in competition to [ 125 I-Tyr 4 ]-Bombesin in the human prostate cancer cell line PC-3. A preliminary biodistribution in normal rats was performed, while first microPET images were assessed in male Copenhagen rats bearing the androgen-independent Dunning R-3327-AT-1 prostate cancer tumor. Results: The affinity to GRP receptors in the PC-3 cell line was higher for nat Ga-DOTA-BN[2-14]NH 2 (IC 50 (nM)=0.85±0.06) than that of nat Sc-DOTA-BN[2-14]NH 2 (IC 50 (nM)=6.49±0.13). The internalization rate of 68 Ga labeled DOTA-BN[2-14]NH 2 was slower than that of 44 Sc, but their final internalization percents were comparable. 68 Ga-DOTA-BN[2-14]NH 2 was externalized faster than 44 Sc-DOTA-BN[2-14]NH 2 . The biodistribution of 44 Sc-DOTA-BN[2-14]NH 2 and 68 Ga-DOTA-BN[2-14]NH 2 in normal rats revealed a higher uptake in target organs and tissues of the first one while both excreted mainly through urinary tract. In microPET images both tracers were accumulated in the tumor with similar uptake patterns. Conclusions: Despite the differences in the receptor affinity both the 68 Ga- and the 44 Sc-labeled DOTA-BN[2-14]NH 2 tracers showed comparable distribution and similar time constants of uptake and elimination. Moreover no differences in tumor accumulation (neither in the overall uptake nor in the dynamics) were observed from the microPet imaging. From that perspective the use of either 44 Sc or 68 Ga for detecting tumors with GRP receptors is equivalent. - Highlights: ► In vitro and in vivo evaluation of 44 Sc- and 68 Ga-DOTA-BN[2-14]NH 2 in reference to published

New separation method of no-carrier-added {sup 47}Sc from titanium targets

Energy Technology Data Exchange (ETDEWEB)

Bartos, B.; Majkowska, A.; Kasperek, A.; Krajewski, S.; Bilewicz, A. [Institute of Nuclear Chemistry and Technology, Warszawa (Poland). Nuclear Chemistry and Radiochemistry Center

2012-07-01

Radionuclides with medium energy beta emission and a several day half-life are attractive candidates for radioimmunotherapy. Among the most promising in this category is {sup 47}Sc produced by fast neutron irradiation (E{sub n} > 1 MeV) of titanium target with high energy neutrons in {sup 47}Ti(n,p){sup 47}Sc nuclear reaction. In the previously reported production scheme the dissolution of the TiO{sub 2} target in hot concentrated H{sub 2}SO{sub 4} and evaporation of the resulting solution were the most time-consuming steps. The present paper describes new, simple and efficient production method of {sup 47}Sc, where the slow dissolution of the target is avoided. After irradiation in fast neutron flux {sup 47}TiO{sub 2} and Li{sub 2}{sup 47}TiF{sub 6} targets were dissolved in HF solutions. Next {sup 47}Sc was separated from the target using anion exchange resin Dowex 1 with 0.4 M HF + 0.06 M HNO{sub 3} solution as eluent. The eluted {sup 47}Sc was adsorbed on cation exchange resin and eluted with 0.5 M of ammonium acetate. The 47Sc separation yield in the proposed procedure is about 90% with the separation time less than 2 h. The obtained no-carrier-added {sup 47}Sc was used to label DOTATATE conjugate with 96% labeling yield. (orig.)

Enhanced hardness in epitaxial TiAlScN alloy thin films and rocksalt TiN/(Al,Sc)N superlattices

Energy Technology Data Exchange (ETDEWEB)

Saha, Bivas [School of Materials Engineering, Purdue University, West Lafayette, Indiana 47907 (United States); Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907 (United States); Lawrence, Samantha K.; Bahr, David F. [School of Materials Engineering, Purdue University, West Lafayette, Indiana 47907 (United States); Schroeder, Jeremy L.; Birch, Jens [Thin Film Physics Division, Department of Physics, Chemistry, and Biology (IFM), Linköping University, SE-581 83 Linköping (Sweden); Sands, Timothy D. [School of Materials Engineering, Purdue University, West Lafayette, Indiana 47907 (United States); Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907 (United States); School of Electrical and Computer Engineering, Purdue University, West Lafayette, Indiana 47907 (United States)

2014-10-13

High hardness TiAlN alloys for wear-resistant coatings exhibit limited lifetimes at elevated temperatures due to a cubic-AlN to hexagonal-AlN phase transformation that leads to decreasing hardness. We enhance the hardness (up to 46 GPa) and maximum operating temperature (up to 1050 °C) of TiAlN-based coatings by alloying with scandium nitride to form both an epitaxial TiAlScN alloy film and epitaxial rocksalt TiN/(Al,Sc)N superlattices on MgO substrates. The superlattice hardness increases with decreasing period thickness, which is understood by the Orowan bowing mechanism of the confined layer slip model. These results make them worthy of additional research for industrial coating applications.

Superconducting cavity driving with FPGA controller

Energy Technology Data Exchange (ETDEWEB)

Czarski, T.; Koprek, W.; Pozniak, K.T.; Romaniuk, R.S. [Warsaw Univ. of Technology (Poland); Simrock, S.; Brand, A. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Chase, B.; Carcagno, R.; Cancelo, G. [Fermi National Accelerator Lab., Batavia, IL (United States); Koeth, T.W. [Rutgers - the State Univ. of New Jersey, NJ (United States)

2006-07-01

The digital control of several superconducting cavities for a linear accelerator is presented. The laboratory setup of the CHECHIA cavity and ACC1 module of the VU-FEL TTF in DESY-Hamburg have both been driven by a Field Programmable Gate Array (FPGA) based system. Additionally, a single 9-cell TESLA Superconducting cavity of the FNPL Photo Injector at FERMILAB has been remotely controlled from WUT-ISE laboratory with the support of the DESY team using the same FPGA control system. These experiments focused attention on the general recognition of the cavity features and projected control methods. An electrical model of the resonator was taken as a starting point. Calibration of the signal path is considered key in preparation for the efficient driving of a cavity. Identification of the resonator parameters has been proven to be a successful approach in achieving required performance; i.e. driving on resonance during filling and field stabilization during flattop time while requiring reasonable levels of power consumption. Feed-forward and feedback modes were successfully applied in operating the cavities. Representative results of the experiments are presented for different levels of the cavity field gradient. (orig.)

Superconducting cavity driving with FPGA controller

International Nuclear Information System (INIS)

Czarski, T.; Koprek, W.; Pozniak, K.T.; Romaniuk, R.S.; Simrock, S.; Brand, A.; Chase, B.; Carcagno, R.; Cancelo, G.; Koeth, T.W.

2006-01-01

The digital control of several superconducting cavities for a linear accelerator is presented. The laboratory setup of the CHECHIA cavity and ACC1 module of the VU-FEL TTF in DESY-Hamburg have both been driven by a Field Programmable Gate Array (FPGA) based system. Additionally, a single 9-cell TESLA Superconducting cavity of the FNPL Photo Injector at FERMILAB has been remotely controlled from WUT-ISE laboratory with the support of the DESY team using the same FPGA control system. These experiments focused attention on the general recognition of the cavity features and projected control methods. An electrical model of the resonator was taken as a starting point. Calibration of the signal path is considered key in preparation for the efficient driving of a cavity. Identification of the resonator parameters has been proven to be a successful approach in achieving required performance; i.e. driving on resonance during filling and field stabilization during flattop time while requiring reasonable levels of power consumption. Feed-forward and feedback modes were successfully applied in operating the cavities. Representative results of the experiments are presented for different levels of the cavity field gradient. (orig.)

Martensitic Transformation in a β-Type Mg-Sc Alloy

Science.gov (United States)

Ogawa, Yukiko; Ando, Daisuke; Sutou, Yuji; Somekawa, Hidetoshi; Koike, Junichi

2018-03-01

Recently, we found that a Mg-Sc alloy with a bcc (β) phase exhibits superelasticity and a shape memory effect at low temperature. In this work, we examined the stress-induced and thermally induced martensitic transformation of the β-type Mg-Sc alloy and investigated the crystal structure of the thermally induced martensite phase based on in situ X-ray diffraction (XRD) measurements. The lattice constants of the martensite phase were calculated to be a = 0.3285 nm, b = 0.5544 nm, and c = 0.5223 nm when we assumed that the martensite phase has an orthorhombic structure (Cmcm). Based on the lattice correspondence between a bcc and an orthorhombic structures such as that in the case of β-Ti shape memory alloys, we estimated the transformation strain of the β Mg-Sc alloy. As a result, the transformation strains along the 001, 011, and 111 directions in the β phase were calculated to be + 5.7, + 8.8, and + 3.3%, respectively.

Martensitic Transformation in a β-Type Mg-Sc Alloy

Science.gov (United States)

Ogawa, Yukiko; Ando, Daisuke; Sutou, Yuji; Somekawa, Hidetoshi; Koike, Junichi

2017-12-01

Recently, we found that a Mg-Sc alloy with a bcc (β) phase exhibits superelasticity and a shape memory effect at low temperature. In this work, we examined the stress-induced and thermally induced martensitic transformation of the β-type Mg-Sc alloy and investigated the crystal structure of the thermally induced martensite phase based on in situ X-ray diffraction (XRD) measurements. The lattice constants of the martensite phase were calculated to be a = 0.3285 nm, b = 0.5544 nm, and c = 0.5223 nm when we assumed that the martensite phase has an orthorhombic structure (Cmcm). Based on the lattice correspondence between a bcc and an orthorhombic structures such as that in the case of β-Ti shape memory alloys, we estimated the transformation strain of the β Mg-Sc alloy. As a result, the transformation strains along the 001, 011, and 111 directions in the β phase were calculated to be + 5.7, + 8.8, and + 3.3%, respectively.

The development of the code package PERMAK--3D//SC--1

International Nuclear Information System (INIS)

Bolobov, P. A.; Oleksuk, D. A.

2011-01-01

Code package PERMAK-3D//SC-1 was developed for performing pin-by-pin coupled neutronic and thermal hydraulic calculation of the core fragment of seven fuel assemblies and was designed on the basis of 3D multigroup pin-by-pin code PERMAK-3D and 3D (subchannel) thermal hydraulic code SC-1 The code package predicts axial and radial pin-by-pin power distribution and coolant parameters in stimulated region (enthalpies,, velocities,, void fractions,, boiling and DNBR margins).. The report describes some new steps in code package development. Some PERMAK-3D//SC-1 outcomes of WWER calculations are presented in the report. (Authors)

Assembly of a supercrystal (SC) of the CMS endcap electromagnetic calorimeter

CERN Multimedia

J. Williams et al., RAL

2004-01-01

The first three pictures show the insertion of the first three rows of crystals into the supercrystal SC03 on Jan. 2004 and the completion of the SC endstops. Fig. 4 shows a complete supercrystal and Fig. 5 its components (alveolar, interface plate, housing, optical fibre, insert, crystal and VPT, endstop). A set of 25 inserts is shown in Fig. 6, while Fig. 7 shows housing, interface plates and inserts. Finally, a SC rear view showing the Vacum Phototriode (VPT) wires through the inserts can be seen in Fig. 8. Fig. 9 and 10 show two supercrystals under test on Dee F and R, respectively.

Experimental Study on Temperature Behavior of SC Structures under Pure Bending

International Nuclear Information System (INIS)

Ham, K. W.; Lee, K. J.; Park, D. S.; Jeon, J. H.

2006-01-01

SC(Steel plate Concrete) module method uses steel plate instead of reinforcing bar and mold in existing RC structure. Steel plate modules are fabricated in advance, installed and poured with concrete in construction field, so construction period is remarkably shortened by SC module technique. In case of existence of temperature gap between internal and external structure surface such as spent fuel storage pool, thermal stress is taken place and as a result of it, structural strength is deteriorated. In this study, we designed three test specimens and several tests with or without temperature heating were conducted to evaluate temperature behavior of SC structures under pure bending loading condition

Opto-mechanical design of a buckling cavity in a novel high-performance outside-plant robust field installable single-mode fibre connector

Science.gov (United States)

Ebraert, Evert; Van Erps, Jürgen; Beri, Stefano; Watté, Jan; Thienpont, Hugo

2014-05-01

Fibre-to-the-home (FTTH) networks provide an ideal means to reach the goal the European Union has set to provide 50 % of the households with a broadband connection faster than 100 Mb/s. Deployment of FTTH networks, which is still costly today, could be significantly boosted by novel ferrule-less connectors which don't require highly skilled personnel and allow installation in the field. We propose a ferrule-less connector in which two single-mode fibres (SMFs) are aligned and maintain physical contact by ensuring that at least one fibre is in a buckled state. To this end, we design a cavity in which a fibre can buckle in a controlled way. Using finite element analysis simulations to investigate the shape of the formed buckle for various buckling cavity lengths, we show that it can be accurately approximated by a cosine function. In addition, the optical performance of a buckled SMF is investigated by bending loss calculations and simulations. We show a good agreement between the analytical and the simulated bending loss results for a G.652 fibre at a wavelength of 1550 nm. Buckling cavity lengths smaller than 20 mm should be avoided to keep the optical bending loss due to buckling below 0.1 dB. In this case the cavity height should at least be 2 mm to avoid mechanical confinement of the fibre.

Final Scientific Report: DE-SC0008580

Energy Technology Data Exchange (ETDEWEB)

Seidler, Gerald T. [Univ. of Washington, Seattle, WA (United States)

2017-03-16

We report scientific, technical, and organizational accomplishments under DE-SC0008580. This includes 10 publications, 5 patent or provisional patent applications, beamtime with important results at both LCLS and APS, and new progress in understanding target design for x-ray heating experiments at x-ray heating facilities.

Observed travel times for Multiply-reflected ScS waves from a deep-focus earthquake

Directory of Open Access Journals (Sweden)

A. F. ESPISOSA

1966-06-01

Full Text Available Tlie deep-focus Argentinean earthquake of December 8
1962, generated multiply reflected ScS phases which were recorded very
clearly at stations of the IGY and the TJSC&GS standardized worldwide
networks and at Canadian stations. The data gathered from this earthquake
for the multiply-reflected ScS and sScS were used to construct the
travel times and to extend them to shorter epicentral distances. These
new data brought to light an error in published travel times for the 2(ScS
phase.

Transport of one SC coil through the village of Meyrin

CERN Multimedia

1956-01-01

In 1952, before CERN was officially founded, two accelerator projects were launched: one for an innovative accelerator to operate at an energy level unequalled at the time, the other for a more standard machine, a Synchro-Cyclotron (SC) to operate at 600 MeV. Design work on the SC was started in 1952 and carried out by teams scattered throughout Europe. Once construction began in 1954, CERN had to arrange road transport for the first of what has since been a long series of spectacular component deliveries, such as those of the machine's two magnetic coils each weighing 60 tonnes and measuring 7.2 metres in diameter. Above, one of them is seen passing through the village of Meyrin. The SC was commissioned in 1957 and was operational for 34 years!

Image transmission through a stable paraxial cavity

International Nuclear Information System (INIS)

Gigan, Sylvain; Lopez, Laurent; Treps, Nicolas; Maitre, Agnes; Fabre, Claude

2005-01-01

We study the transmission of a monochromatic 'image' through a paraxial cavity. Using the formalism of self-transform functions, we show that a transverse degenerate cavity transmits the self-transform part of the image, with respect to the field transformation over one round-trip of the cavity. This formalism gives insight into the understanding of the behavior of a transverse degenerate cavity, complementary to the transverse mode picture. An experiment of image transmission through a hemiconfocal cavity shows the interest of this approach

A drought severity climatology for the Carpathian Region using Sc-PDSI

Science.gov (United States)

Antofie, Tiberiu; Naumann, Gustavo; Spinoni, Jonathan; Weynants, Melanie; Szalai, Sandor; Szentimrey, Tamas; Bihari, Zita; Vogt, Jürgen

2013-04-01

Monthly grids of the self-calibrating Palmer Drought Severity Index (Sc-PDSI) have been calculated for the period 1961-2010 for the Carpathian Region (17˚-27˚E, 44˚-50˚N) with a spatial resolution of 0.1˚x 0.1˚. Using the Sc-PDSI and the assumptions of the Palmer Drought Model (PDM), the approximated precipitation required for drought termination (achieved when the Sc-PDSI turns back above -0.5) and amelioration (achieved when the Sc-PDSI value turns back above -2.0) are computed for periods of 1, 3, 6, and 9 months. The Sc-PDSI is based on a modified version of the Palmer Drought Severity Index (PDSI), first introduced by Palmer (1965) with the intent to measure the cumulative departure (related to local normal conditions) of moisture supply and demand. Due to its empirically derived climatic characteristic (K) and duration factors - limited to U.S. climatic conditions - Wells et al. (2004) improved it and transformed the PDSI into the Sc-PDSI, which is more appropriate for spatial comparisons in different climatic regions. The Sc-PDSI is based on the supply-and-demand concept of a complex water budget system based on precipitation and temperature records and also on the soil characteristics at any location. The inputs used in this study are the Available Water Capacity of the soil (AWC) derived from the soil texture (European Soil Database of JRC) with a spatial resolution of 0.1˚x0.1˚, Potential Evapo-Transpiration (PET), and 6 hydrological parameters of the soil water balance: recharge, runoff, loss, and their potential values (used in the calculation of Palmer's constants to define the normal climate for the specific location, i.e. the so called CAFEC). PET has been computed using the 0.1˚x 0.1˚ gridded monthly precipitation and mean temperature for 1961-2010 provided by the CARPATCLIM project in the framework of the construction of a Climate Atlas for the Carpathian Region. The Sc-PDSI focuses on the monthly anomalies of the soil moisture, thus it

L-Arginine ethylester enhances in vitro amplification of PrP(Sc) in macaques with atypical L-type bovine spongiform encephalopathy and enables presymptomatic detection of PrP(Sc) in the bodily fluids.

Science.gov (United States)

Murayama, Y; Ono, F; Shimozaki, N; Shibata, H

2016-02-12

Protease-resistant, misfolded isoforms (PrP(Sc)) of a normal cellular prion protein (PrP(C)) in the bodily fluids, including blood, urine, and saliva, are expected to be useful diagnostic markers of prion diseases, and nonhuman primate models are suited for performing valid diagnostic tests for human Creutzfeldt-Jakob disease (CJD). We developed an effective amplification method for PrP(Sc) derived from macaques infected with the atypical L-type bovine spongiform encephalopathy (L-BSE) prion by using mouse brain homogenate as a substrate in the presence of polyanions and L-arginine ethylester. This method was highly sensitive and detected PrP(Sc) in infected brain homogenate diluted up to 10(10) by sequential amplification. This method in combination with PrP(Sc) precipitation by sodium phosphotungstic acid is capable of amplifying very small amounts of PrP(Sc) contained in the cerebrospinal fluid (CSF), saliva, urine, and plasma of macaques that have been intracerebrally inoculated with the L-BSE prion. Furthermore, PrP(Sc) was detectable in the saliva or urine samples as well as CSF samples obtained at the preclinical phases of the disease. Thus, our novel method may be useful for furthering the understanding of bodily fluid leakage of PrP(Sc) in nonhuman primate models. Copyright © 2016 Elsevier Inc. All rights reserved.

Correlative characterization of primary Al{sub 3}(Sc,Zr) phase in an Al–Zn–Mg based alloy

Energy Technology Data Exchange (ETDEWEB)

Li, J.H., E-mail: jie-hua.li@hotmail.com [Institute of Casting Research, Montanuniversität Leoben, A-8700 Leoben (Austria); Wiessner, M. [Materials Center Leoben Forschung GmbH, A-8700 Leoben (Austria); Albu, M. [Institute for Electron Microscopy and Nanoanalysis, Graz University of Technology, Center for Electron Microscopy (Austria); Wurster, S. [Department of Materials Physics, Montanuniversität Leoben, Erich Schmid Institute of Materials Science of the Austrian Academy of Sciences, A-8700 Leoben (Austria); Sartory, B. [Materials Center Leoben Forschung GmbH, A-8700 Leoben (Austria); Hofer, F. [Institute for Electron Microscopy and Nanoanalysis, Graz University of Technology, Center for Electron Microscopy (Austria); Schumacher, P. [Institute of Casting Research, Montanuniversität Leoben, A-8700 Leoben (Austria); Austrian Foundry Research Institute, A-8700 Leoben (Austria)

2015-04-15

Three-dimensional electron backscatter diffraction, focused ion beam, transmission electron microscopy and energy filtered transmission electron microscopy were employed to investigate the structural information of primary Al{sub 3}(Sc,Zr) phase, i.e. size, shape, element distribution and orientation relationship with the α-Al matrix. It was found that (i) most primary Al{sub 3}(Sc,Zr) phases have a cubic three-dimensional morphology, with a size of about 6–10 μm, (ii) most primary Al{sub 3}(Sc,Zr) phases are located within the α-Al matrix, and exhibit a cube to cube orientation relationship with the α-Al matrix, and (iii) a layer by layer growth was observed within primary Al{sub 3}(Sc,Zr) phases. Al, Cu, Si and Fe are enriched in the α-Al matrix between the layers of cellular eutectic Al{sub 3}(Sc,Zr) phase, while Sc, Ti and Zr are enriched in small Al{sub 3}(Sc,Zr) phases. A peritectic reaction and subsequent eutectic reaction between Al{sub 3}Sc and Al was proposed to interpret the observed layer by layer growth. This paper demonstrates that the presence of impurities (Fe, Si, Cu, Ti) in the diffusion field surrounding the growing Al{sub 3}(Sc,Zr) particle enhances the heterogeneous nucleation of Al{sub 3}(Sc,Zr) phases. - Highlights: • Most fine cubic primary Al{sub 3}(Sc,Zr) phases were observed within the α-Al matrix. • A layer by layer growth within primary Al{sub 3}(Sc,Zr) phase was observed. • A peritectic and subsequent eutectic reaction between Al{sub 3}Sc and Al was proposed. • Impurities in diffusion fields enhance heterogeneous nucleation of Al{sub 3}(Sc,Zr)

Cryostat for TRISTAN superconducting cavity

International Nuclear Information System (INIS)

Mitsunobu, S.; Furuya, T.; Hara, K.

1990-01-01

Superconducting cavities generate rather high heat load of hundreds watts in one cryostat and have high sensitivity for pressure. We adopted usual pool-boiling type cooling for its stable pressure operation. Two 5-cell Nb cavities were installed in one flange type cryostat. Tuning mechanics actuated by a pulse-motor and a Piezo-electric element are set at outside of vacuum end flange. The design and performance of the cryostat for TRISTAN superconducting cavities are described. (author)

MUON DETECTORS: ALIGNMENT

CERN Multimedia

M. Dallavalle

2013-01-01

A new Muon misalignment scenario for 2011 (7 TeV) Monte Carlo re-processing was re-leased. The scenario is based on running of standard track-based reference-target algorithm (exactly as in data) using single-muon simulated sample (with the transverse-momentum spectrum matching data). It used statistics similar to what was used for alignment with 2011 data, starting from an initially misaligned Muon geometry from uncertainties of hardware measurements and using the latest Tracker misalignment geometry. Validation of the scenario (with muons from Z decay and high-pT simulated muons) shows that it describes data well. The study of systematic uncertainties (dominant by now due to huge amount of data collected by CMS and used for muon alignment) is finalised. Realistic alignment position errors are being obtained from the estimated uncertainties and are expected to improve the muon reconstruction performance. Concerning the Hardware Alignment System, the upgrade of the Barrel Alignment is in progress. By now, d...

MUON DETECTORS: ALIGNMENT

CERN Multimedia

G. Gomez

2011-01-01

A new set of muon alignment constants was approved in August. The relative position between muon chambers is essentially unchanged, indicating good detector stability. The main changes concern the global positioning of the barrel and of the endcap rings to match the new Tracker geometry. Detailed studies of the differences between track-based and optical alignment of DTs have proven to be a valuable tool for constraining Tracker alignment weak modes, and this information is now being used as part of the alignment procedure. In addition to the “split-cosmic” analysis used to investigate the muon momentum resolution at high momentum, a new procedure based on reconstructing the invariant mass of di-muons from boosted Zs is under development. Both procedures show an improvement in the momentum precision of Global Muons with respect to Tracker-only Muons. Recent developments in track-based alignment include a better treatment of the tails of residual distributions and accounting for correla...

ORF Alignment: NC_005364 [GENIUS II[Archive

Lifescience Database Archive (English)

Full Text Available ia ligase [Mycoplasma mycoides subsp. mycoides SC ... str. PG1] ref|NP_975979.1| ASPARTATE-AMMONIA LI...nia ligase [Mycoplasma ... mycoides subsp. mycoides SC] emb|CAE77621.1| ... ASPARTATE-AMMONI

Lanthanide-doped NaScF4 nanoprobes: crystal structure, optical spectroscopy and biodetection.

Science.gov (United States)

Ai, Yu; Tu, Datao; Zheng, Wei; Liu, Yongsheng; Kong, Jintao; Hu, Ping; Chen, Zhuo; Huang, Mingdong; Chen, Xueyuan

2013-07-21

Trivalent lanthanide ions (Ln(3+))-doped inorganic nanoparticles (NPs) as potential luminescent bioprobes have been attracting tremendous interest because of their unique upconversion (UC) and downconversion (DC) luminescence properties. NaScF4, as an important host material, has been rarely reported and its crystal structure remains unclear. Herein, based on the single crystal X-ray diffraction, the space group of NaScF4 crystals was determined to be P31 containing multiple sites of Sc(3+) with crystallographic site symmetry of C1, which was verified by high-resolution photoluminescence spectroscopy of Eu(3+) at low temperature (10 K). Furthermore, monodisperse and size-controllable NaScF4:Ln(3+) NPs were synthesized via a facile thermal decomposition method. The biotinylated NaScF4:Er(3+)/Yb(3+) NPs were demonstrated for their applications as a heterogeneous UC luminescence bioprobe to detect avidin with a detection limit of 180 pM. After bioconjugation with amino-terminal fragment (ATF) of urokinase plasminogen activator (uPA), NaScF4:Ln(3+) NPs also exhibited specific recognition of cancer cells overexpressed with uPA receptor (uPAR, an important marker of tumor biology and metastasis), showing great potentials in tumor-targeted bioimaging.

Reduction of the thermal conductivity of the thermoelectric material ScN by Nb alloying

DEFF Research Database (Denmark)

Tureson, Nina; Van Nong, Ngo; Fournier, Daniele

2017-01-01

) orientation. The crystal structure, morphology, thermal conductivity, and thermoelectric and electrical properties were investigated. The ScN reference film exhibited a Seebeck coefficient of −45 μV/K and a power factor of 6 × 10−4 W/m K2 at 750 K. Estimated from room temperature Hall measurements, all...... samples exhibit a high carrier density of the order of 1021 cm−3. Inclusion of heavy transition metals into ScN enables the reduction in thermal conductivity by an increase in phonon scattering. The Nb inserted ScN thin films exhibited a thermal conductivity lower than the value of the ScN reference (10.......5 W m−1 K−1) down to a minimum value of 2.2 Wm−1 K−1. Insertion of Nb into ScN thus resulted in a reduction in thermal conductivity by a factor of ∼5 due to the mass contrast in ScN, which increases the phonon scattering in the material....

Effects of powder flowability on the alignment degree and magnetic properties for NdFeB sintermagnets

Energy Technology Data Exchange (ETDEWEB)

Sun, Y. [School of Physics and Microelectronics, Shandong University, 250100 (China); Gao, R.W. [School of Physics and Microelectronics, Shandong University, 250100 (China)]. E-mail: gaorwbox@sdu.edu.cn; Han, G.B. [School of Physics and Microelectronics, Shandong University, 250100 (China); Bai, G. [School of Physics and Microelectronics, Shandong University, 250100 (China); Liu, T. [School of Physics and Microelectronics, Shandong University, 250100 (China); Wang, B. [School of Physics and Microelectronics, Shandong University, 250100 (China); Yantai Shougang Magnetic Material CO, LTD, 265500 (China)

2006-04-15

The magnetic powders for sintered NdFeB magnets have been prepared by using the strip casting (SC), hydrogen decrepitation (HD) and jet milling (JM) techniques. The effects of powder flowability and addition of a lubricant on the alignment degree and the hard magnetic properties of sintered magnets have been studied. The results show that the main factor affecting powder flowability is the aggregation of magnetic particles for powders in a loose state, but it is the friction between the powder particles for powders that are in a compact state. The addition of a lubricant with suitable dose can slightly prevent the congregating of powders, obviously decrease the friction between the powder particles, improve the powder flowability, and increase the alignment degree, remanence and energy product density of sintered magnets. Mixing a suitable dose of lubricant and adopting rubber isostatic pressing (RIP) with a pulse magnetic field, we have succeeded in producing the sintered NdFeB magnet with high hard magnetic properties of B {sub r}=14.57 KG, {sub j}H {sub c}=14.43 KOe (BH){sub max}=51.3 MGOe.

Reducing beam shaper alignment complexity: diagnostic techniques for alignment and tuning

Science.gov (United States)

Lizotte, Todd E.

2011-10-01

Safe and efficient optical alignment is a critical requirement for industrial laser systems used in a high volume manufacturing environment. Of specific interest is the development of techniques to align beam shaping optics within a beam line; having the ability to instantly verify by a qualitative means that each element is in its proper position as the beam shaper module is being aligned. There is a need to reduce these types of alignment techniques down to a level where even a newbie to optical alignment will be able to complete the task. Couple this alignment need with the fact that most laser system manufacturers ship their products worldwide and the introduction of a new set of variables including cultural and language barriers, makes this a top priority for manufacturers. Tools and methodologies for alignment of complex optical systems need to be able to cross these barriers to ensure the highest degree of up time and reduce the cost of maintenance on the production floor. Customers worldwide, who purchase production laser equipment, understand that the majority of costs to a manufacturing facility is spent on system maintenance and is typically the largest single controllable expenditure in a production plant. This desire to reduce costs is driving the trend these days towards predictive and proactive, not reactive maintenance of laser based optical beam delivery systems [10]. With proper diagnostic tools, laser system developers can develop proactive approaches to reduce system down time, safe guard operational performance and reduce premature or catastrophic optics failures. Obviously analytical data will provide quantifiable performance standards which are more precise than qualitative standards, but each have a role in determining overall optical system performance [10]. This paper will discuss the use of film and fluorescent mirror devices as diagnostic tools for beam shaper module alignment off line or in-situ. The paper will also provide an overview

Tidal alignment of galaxies

Energy Technology Data Exchange (ETDEWEB)

Blazek, Jonathan; Vlah, Zvonimir; Seljak, Uroš

2015-08-01

We develop an analytic model for galaxy intrinsic alignments (IA) based on the theory of tidal alignment. We calculate all relevant nonlinear corrections at one-loop order, including effects from nonlinear density evolution, galaxy biasing, and source density weighting. Contributions from density weighting are found to be particularly important and lead to bias dependence of the IA amplitude, even on large scales. This effect may be responsible for much of the luminosity dependence in IA observations. The increase in IA amplitude for more highly biased galaxies reflects their locations in regions with large tidal fields. We also consider the impact of smoothing the tidal field on halo scales. We compare the performance of this consistent nonlinear model in describing the observed alignment of luminous red galaxies with the linear model as well as the frequently used "nonlinear alignment model," finding a significant improvement on small and intermediate scales. We also show that the cross-correlation between density and IA (the "GI" term) can be effectively separated into source alignment and source clustering, and we accurately model the observed alignment down to the one-halo regime using the tidal field from the fully nonlinear halo-matter cross correlation. Inside the one-halo regime, the average alignment of galaxies with density tracers no longer follows the tidal alignment prediction, likely reflecting nonlinear processes that must be considered when modeling IA on these scales. Finally, we discuss tidal alignment in the context of cosmic shear measurements.

Fast global sequence alignment technique

KAUST Repository

Bonny, Mohamed Talal; Salama, Khaled N.

2011-01-01

fast alignment algorithm, called 'Alignment By Scanning' (ABS), to provide an approximate alignment of two DNA sequences. We compare our algorithm with the wellknown sequence alignment algorithms, the 'GAP' (which is heuristic) and the 'Needleman

Fluid Density and Impact Cavity Formation

Directory of Open Access Journals (Sweden)

Ga-Chun Lin

2018-01-01

Full Text Available Characteristics of the impact cavity formed when a steel ball is dropped into aqueous solutions of densities ranging from 0.98 g·cm-3 to 1.63 g·cm-3 were investigated. A high-speed camera was used to record the formation and collapse of the cavity. The results showed cavity diameter, volume, and pinch-off time are independent of fluid density, on average. There was an unexplained reduction in cavity formation for densities of 1.34 g·cm-3 and 1.45 g·cm-3.

LARGE-SCALE FLOWS IN PROMINENCE CAVITIES

International Nuclear Information System (INIS)

Schmit, D. J.; Gibson, S. E.; Tomczyk, S.; Reeves, K. K.; Sterling, Alphonse C.; Brooks, D. H.; Williams, D. R.; Tripathi, D.

2009-01-01

Regions of rarefied density often form cavities above quiescent prominences. We observed two different cavities with the Coronal Multichannel Polarimeter on 2005 April 21 and with Hinode/EIS on 2008 November 8. Inside both of these cavities, we find coherent velocity structures based on spectral Doppler shifts. These flows have speeds of 5-10 km s -1 , occur over length scales of tens of megameters, and persist for at least 1 hr. Flows in cavities are an example of the nonstatic nature of quiescent structures in the solar atmosphere.

Demountable damped cavity for HOM-damping in ILC superconducting accelerating cavities

Energy Technology Data Exchange (ETDEWEB)

Konomi, T., E-mail: konomi@ims.ac.jp [High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan); Yasuda, F. [University of Tokyo, Bunkyo-ku, Tokyo 113-8654 (Japan); Furuta, F. [Laboratory for Elementary-Particle Physics, Cornell University, Ithaca, NY 14853 (United States); Saito, K. [High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan)

2014-01-11

We have designed a new higher-order-mode (HOM) damper called a demountable damped cavity (DDC) as part of the R and D efforts for the superconducting cavity of the International Linear Collider (ILC). The DDC has two design concepts. The first is an axially symmetrical layout to obtain high damping efficiency. The DDC has a coaxial structure along the beam axis to realize strong coupling with HOMs. HOMs are damped by an RF absorber at the end of the coaxial waveguide and the accelerating mode is reflected by a choke filter mounted at the entrance of the coaxial waveguide. The second design concept is a demountable structure to facilitate cleaning, in order to suppress the Q-slope problem in a high field. A single-cell cavity with the DDC was fabricated to test four performance parameters. The first was frequency matching between the accelerating cavity and the choke filter. Since the bandwidth of the resonance frequency in a superconducting cavity is very narrow, there is a possibility that the accelerating field will leak to the RF absorber because of thermal shrinkage. The design bandwidth of the choke filter is 25 kHz. It was demonstrated that frequency matching adjusted at room temperature could be successfully maintained at 2 K. The second parameter was the performance of the demountable structure. At the joint, the magnetic field is 1/6 of the maximum field in the accelerating cavity. Ultimately, the accelerating field reached 19 MV/m and Q{sub 0} was 1.5×10{sup 10} with a knife-edge shape. The third parameter was field emission and multipacting. Although the choke structure has numerous parallel surfaces that are susceptible to the multipacting problem, it was found that neither field emission nor multipacting presented problems in both an experiment and simulation. The final parameter was the Q values of the HOM. The RF absorber adopted in the system is a Ni–Zn ferrite type. The RF absorber shape was designed based on the measurement data of permittivity

Demountable damped cavity for HOM-damping in ILC superconducting accelerating cavities

International Nuclear Information System (INIS)

Konomi, T.; Yasuda, F.; Furuta, F.; Saito, K.

2014-01-01

We have designed a new higher-order-mode (HOM) damper called a demountable damped cavity (DDC) as part of the R and D efforts for the superconducting cavity of the International Linear Collider (ILC). The DDC has two design concepts. The first is an axially symmetrical layout to obtain high damping efficiency. The DDC has a coaxial structure along the beam axis to realize strong coupling with HOMs. HOMs are damped by an RF absorber at the end of the coaxial waveguide and the accelerating mode is reflected by a choke filter mounted at the entrance of the coaxial waveguide. The second design concept is a demountable structure to facilitate cleaning, in order to suppress the Q-slope problem in a high field. A single-cell cavity with the DDC was fabricated to test four performance parameters. The first was frequency matching between the accelerating cavity and the choke filter. Since the bandwidth of the resonance frequency in a superconducting cavity is very narrow, there is a possibility that the accelerating field will leak to the RF absorber because of thermal shrinkage. The design bandwidth of the choke filter is 25 kHz. It was demonstrated that frequency matching adjusted at room temperature could be successfully maintained at 2 K. The second parameter was the performance of the demountable structure. At the joint, the magnetic field is 1/6 of the maximum field in the accelerating cavity. Ultimately, the accelerating field reached 19 MV/m and Q 0 was 1.5×10 10 with a knife-edge shape. The third parameter was field emission and multipacting. Although the choke structure has numerous parallel surfaces that are susceptible to the multipacting problem, it was found that neither field emission nor multipacting presented problems in both an experiment and simulation. The final parameter was the Q values of the HOM. The RF absorber adopted in the system is a Ni–Zn ferrite type. The RF absorber shape was designed based on the measurement data of permittivity and

Nanometer cavities studied by positron annihilation

International Nuclear Information System (INIS)

Mogensen, O.E.

1992-01-01

Positronium (Ps) is trapped in cavities in insulating solids, and the lifetime of ortho Ps is determined by the size of the cavity. The information on the properties of the cavities obtained by use of the standard slow positron beam and the 'normal' positron annihilation techniques is compared for several selected cases. (author)

Predictions of laminar natural convection in heated cavities

International Nuclear Information System (INIS)

Winters, K.H.

1982-06-01

Several examples of laminar, natural convection in heated cavities are discussed with illustrative calculations. These include convection in a square cavity at high Rayleigh number; in a narrow cavity at moderate aspect ratio; in a rectangular cavity heated from below; in a trapezoidal cavity, and in a rectangular cavity containing a conducting obstruction. The steady equations for the velocity, pressure and temperature are solved in the Boussinesq approximation, using a standard Galerkin formulation of the finite-element method. (author)

Optimizing complex scandium-3,3 benzilidene BIS [4-hydroxycoumarin] with 46Sc radiotracer

International Nuclear Information System (INIS)

Khanza Aktari Dewi; Muhamad Basit Febrian; Duyeh Setiawan

2015-01-01

Coumarin, coumarin derivatives and coumarin complex compounds known to possess biological activities such as anticancer and antiviral. The reaction between the active compound coumarin derivatives with radioisotopes Sc-46 is expected to give a complex that will be marked for further investigation of its biological activity in purpose of drug development based on coumarin. This study aims to determine the optimum conditions in the synthesis of its complex compounds as well as the physico chemical characteristics including physical properties and radiochemical purity of the complex. 3.3 benzilidene bis [4-hydroxycoumarin] ligand has successfully synthesized by reacting 4-hydroxycoumarin with benzaldehyde. Complex solids formed instantly when the solution ScCl 3 labeled by Sc-46 with a pH of 5 is reacted with a ligand solution with a pH of 11 with the optimum ratio of Sc: ligand were 1:2 with optimum labeling percentage of 99,75 ± 0,02%. FTIR analysis of complex compounds and ligands show some shift in absorption due to the formation of complex. Melting point of ligand was 234°C whilst complex compound was not yet melted in maximum range of Fischer-Jons instrument at 300°C. The complex was white reddish coloured and well soluble in DMSO. Radiochemical purity of the complex Sc-(3,3 benzilidene bis [4-hydroxycoumarin]) 2 .2H 2 O was 91.22%. Complex compound of coumarin labeled by Sc-46 has been successfully synthesized and characterized with proposed molecular formula of Sc-(3,3 benzilidene bis [4-hydroxycoumarin]) 2 .2H 2 O. (author)

High Reflectance Nanoscale V/Sc Multilayer for Soft X-ray Water Window Region.

Science.gov (United States)

Huang, Qiushi; Yi, Qiang; Cao, Zhaodong; Qi, Runze; Loch, Rolf A; Jonnard, Philippe; Wu, Meiyi; Giglia, Angelo; Li, Wenbin; Louis, Eric; Bijkerk, Fred; Zhang, Zhong; Wang, Zhanshan

2017-10-10

V/Sc multilayer is experimentally demonstrated for the first time as a high reflectance mirror for the soft X-ray water window region. It primarily works at above the Sc-L edge (λ = 3.11 nm) under near normal incidence while a second peak appears at above the V-L edge (λ = 2.42 nm) under grazing incidence. The V/Sc multilayer fabricated with a d-spacing of 1.59 nm and 30 bilayers has a smaller interface width (σ = 0.27 and 0.32 nm) than the conventional used Cr/Sc (σ = 0.28 and 0.47 nm). For V/Sc multilayer with 30 bilayers, the introduction of B 4 C barrier layers has little improvement on the interface structure. As the number of bilayers increasing to 400, the growth morphology and microstructure of the V/Sc layers evolves with slightly increased crystallization. Nevertheless, the surface roughness remains to be 0.25 nm. A maximum soft X-ray reflectance of 18.4% is measured at λ = 3.129 nm at 9° off-normal incidence using the 400-bilayers V/Sc multilayer. According to the fitted model, an s-polarization reflectance of 5.2% can also be expected at λ = 2.425 nm under 40° incidence. Based on the promising experimental results, further improvement of the reflectance can be achieved by using a more stable deposition system, exploring different interface engineering methods and so on.

An Original Transformer and Switched-Capacitor (T & SC-Based Extension for DC-DC Boost Converter for High-Voltage/Low-Current Renewable Energy Applications: Hardware Implementation of a New T & SC Boost Converter

Directory of Open Access Journals (Sweden)

Sanjeevikumar Padmanaban

2018-03-01

Full Text Available In this article a new Transformer and Switched Capacitor-based Boost Converter (T & SC-BC is proposed for high-voltage/low-current renewable energy applications. The proposed T & SC-BC is an original extension for DC-DC boost converter which is designed by utilizing a transformer and switched capacitor (T & SC. Photovoltaic (PV energy is a fast emergent segment among the renewable energy systems. The proposed T & SC-BC combines the features of the conventional boost converter and T & SC to achieve a high voltage conversion ratio. A Maximum Power Point Tracking (MPPT controller is compulsory and necessary in a PV system to extract maximum power. Thus, a photovoltaic MPPT control mechanism also articulated for the proposed T & SC-BC. The voltage conversion ratio (Vo/Vin of proposed converter is (1 + k/(1 − D where, k is the turns ratio of the transformer and D is the duty cycle (thus, the converter provides 9.26, 13.88, 50/3 voltage conversion ratios at 78.4 duty cycle with k = 1, 2, 2.6, respectively. The conspicuous features of proposed T & SC-BC are: (i a high voltage conversion ratio (Vo/Vin; (ii continuous input current (Iin; (iii single switch topology; (iv single input source; (v low drain to source voltage (VDS rating of control switch; (vi a single inductor and a single untapped transformer are used. Moreover, the proposed T & SC-BC topology was compared with recently addressed DC-DC converters in terms of number of components, cost, voltage conversion ratio, ripples, efficiency and power range. Simulation and experimental results are provided which validate the functionality, design and concept of the proposed approach.

Additive Manufactured Superconducting Cavities