The mass generation in the Standard Model of Particles Physics relies on a spontaneous symmetry breaking mechanism. Its implementation is recalled, along with its constraints, both theoretical (Naturalness, Stability, Triviality, Unitarity) and experimental (limits of direct and indirect searches, prospects). Calculation techniques for observables evaluation in Perturbative Field Theory are described, particularly Helicity Amplitude method, which is given in details: fermions and vector bosons, massless and massive. Monte-Carlo integration, and structure functions approximations (which allows non-perturbative calculations) are also detailed. With these tools, a process giving to Physics beyond the Standard Model is studied: it leads to an experimental prediction for the LEP collision ring, taking the classical background into account. Technical aspects of a future photon linear collider are reviewed. The production of heavy vector bosons, either the classical Z for ...
We make a comparison of the predicted effective weak mixing angle, the Z-on resonance asymmetries and the W-boson mass to the LEP and SLD data at their present status. We find that the predicted MSSM values for the effective weak mixing angle are in agreement with the LEP+SLD average value for a ``heavy'' SUSY breaking scale while we observe an agreement with SLD data in the case of a ``light'' SUSY breaking scale. The resulting values for the W-boson mass and for the electron left-right asymmetries are compatible with CDF,UA2,DO and LEP data respectively. Unexpectedly we find that the supersymmetric QCD contributions to the Z-observables tend to vanish everywhere in the M1/2-M0 plane. Furthermore, values of M1/2 which are greater than 500 GeV are favoured by the MSSM if one considers the current experimental value for the strong coupling.
The thesis deals with measurement of the mass of the Wboson at LEP2, based on the direct reconstruction of its decay products in the hadronic channel. A set of procedures necessary for the extraction of the W mass from the experimental data collected with the DELPHI detector in 1997 was developed (search of optimal variables for the event selection, development of a special method of kinematical reconstruction). The measured value of the mass was interpreted in the framework of the Standard Model, allowing to constrain the mass of the Higgs boson. A substantial part of the work is devoted to systematic effects due to the interactions between the hadronic decay products of the Wbosons (colour reconnection and Bose-Einstein correlations), which may significantly influence the measurement of their mass. (author) 53 refs., 104 figs., 33 tabs.
We present methods to measure the beam polarizations and the luminosity of [gamma][gamma] colliders at TeV energy scale. The beam polarizations of a [gamma][gamma] collider can easily be monitored by comparing the numbers of events of the processes [gamma][gamma] [yields] l[sup +]l[sup -] and [gamma][gamma] [yields] W[sup +] W[sup -], where l means e or [mu]. The luminosity of a [gamma][gamma] collider is also measurable by the event rate of Wboson pair productions and the light lepton pair productions. (orig.)
We discuss the recent excess seen by the CDF Collaboration in the dijet invariant mass distribution produced in association with a $W$ boson. We analyze the possibility of such a signal within the context of a $U(1)_X$ Stueckelberg extension of the Standard Model where the new gauge boson couples only to quarks. In addition to the analysis of the $Wjj$ anomaly we also discuss the production of $Zjj$ and $\\gamma jj$ at the Tevatron. The analysis is then extended to the Large Hadron Collider with $\\sqrt{s}=7 {\\rm TeV}$ and predictions for the dijet signals are made.
The energy spectra of energetic confined alpha particles are being measured using the pellet charge exchange method [R. K. Fisher, J. S. Leffler, A. M. Howald, and P. B. Parks, Fusion Technol. 13, 536 (1988)]. The technique uses the dense ablation cloud surrounding an injected impurity pellet to neutralize a fraction of the incident alpha particles, allowing them to escape from the plasma where their energy spectrum can be measured using a neutral particle analyzer. The signal calculations given in the above-mentioned reference disregarded the effects of the alpha particles' helical Larmor orbits, which causes the alphas to make multiple passes through the cloud. Other effects such as electron ionization by plasma and ablation cloud electrons and the effect of the charge state composition of the cloud, were also neglected. This report considers these issues, reformulates the signal level calculation, and uses a Monte-Carlo approach to calculate ...
Linear properties of ion temperature gradient (ITG) modes in helical systems are studied. The real frequency, growth rate, and eigenfunction are obtained for both stable and unstable cases by solving a kinetic integral equation with proper analytic continuation performed in the complex frequency plane. Based on the model magnetic configuration for toroidal helical systems like the Large Helical Device (LHD), dependences of the ITG mode properties on various plasma equilibrium parameters are investigated. Particularly, relative effects of {nabla}B-curvature drifts driven by the toroidicity and by the helical ripples are examined in order to compare the ITG modes in helical systems with those in tokamaks. (author)
Associated production of a baryonic Z' boson with the Wboson can account for the excess in Wjj production observed by the CDF collaboration at the Tevatron. We analyze other possible channels of this Z' at the Tevatron and at the LHC, including \\gamma Z' and Z Z' with the Z' -> jj. We show that the chances of confirming this baryonic Z' is better at the Tevatron than at the LHC because of the faster growing backgrounds at the LHC. Unfortunately the current systematic uncertainties of the order of 10% cannot yield any significant excess in both \\gamma Z' and Z Z' channels at the Tevatron and also at the LHC. Nevertheless the search using the b\\bar b decay mode of Z' is much more feasible at the LHC, provided that the branching ratio B(Z' -> b\\bar b) > 0.1. In particular, the W Z' -> l \
We propose central exclusive production of a charged Higgs boson in association with a Wboson as a possible signature of certain types of extended Higgs sectors. We calculate the cross section and find that the rate at the LHC could be large enough to allow observation in some models with two Higgs doublets, where the charged Higgs and at least one of the neutral scalars can be light enough. We use the two-Higgs doublet model as a prototype and consider two distinct regions of parameter space, but we also briefly discuss the prospects for the next-to-minimal supersymmetric standard model, where the charged Higgs may very well be quite light.
Precise measurements of the top quark decay properties at hadron colliders offer interesting new possibilities of testing the standard model. At the same time, recent intriguing experimental results concerning CP violation in the B_d and B_s systems have stimulated many studies of physics beyond the standard model. We investigate anomalous t W d_j interactions as a possible source of new effects in B_{d,s} - bar B_{d,s} oscillations within a model independent approach based on the assumptions of Minimal Flavor Violation. After matching our effective operators onto the low-energy effective Lagrangian describing B_{d,s} meson mixing and evolving it down to the B-mass scale, we extract the preferred ranges of the anomalous t W d_j interactions at the weak scale. These values are then compared to previously considered constraints coming from the rare radiative B --> X_s gamma decay. Finally, we reconsider the associated effects in the t --> b W decays and find that the W ...
To study the three-dimensional (3D) magnetic field topology and its long-term evolution associated with the X3.4 flare of 2006 December 13, we investigate the coronal relative magnetic helicity in the flaring active region (AR) NOAA 10930 during the time period of December 8-14. The coronal helicity is calculated based on the 3D nonlinear force-free magnetic fields reconstructed by the weighted optimization method of Wiegelmann, and is compared with the amount of helicity injected through the photospheric surface of the AR. The helicity injection is determined from the magnetic helicity flux density proposed by Pariat et al. using Solar and Heliospheric Observatory/Michelson Doppler Imager magnetograms. The major findings of this study are the following. (1) The time profile of the coronal helicity shows a good correlation with that of the ...
It has been suggested for quality assurance purposes that linac output variations for helical tomotherapy (HT) be within ±2% of the long-term average. Due to cancellation of systematic...Full Text Available
Since the beam width on the helical tomotherapy machine produced by TomoTherapy, Inc. is typically a few centimeters in the longitudinal direction (into the bore), the optimizer must choose...Full Text Available
Experimental investigation of heat transfer and friction factor characteristics of circular tube fitted with full-length helical screw element of different twist ratio, and helical screw inserts with spacer length 100, 200, 300 and 400mm have been studied with uniform heat flux under laminar flow condition. The experimental data obtained are verified with those obtained from plain tube published data. The effect of spacer length on heat transfer augmentation and friction factor, and the effect of twist ratio on heat transfer augmentation and friction factor have been presented separately. The decrease in Nusselt number for the helical twist with spacer length is within 10% for each subsequent 100mm increase in spacer length. The decrease in friction factor is nearly two times lower than the full length helical twist at low Reynolds number, and four times lower than the full length ...
Purpose:To investigate the clinical usage of dose verification of Helical Tomotherapy plans by using 2D-array ion chambers, and to develop an efficient way to validate the dose delivered...Full Text Available
This design manual contains descriptions of design procedures and operating experience to date, including results obtained, for secondary flow pollution control devices. Two types of combined sewer overflow regulators are described: the swirl and the helical bend regulator/separa...
BackgroundTo compare the differences in dose-volume data among coplanar intensity modulated radiotherapy (IMRT), noncoplanar IMRT, and helical tomotherapy (HT) among patients with...Full Text Available
Purpose: Reverse helical cone-beam computed tomography (CBCT) is a scanning configuration for potential applications in image-guided radiation therapy in which an accurate anatomic image...Full Text Available
In this paper, we show how to calculate analytically the one-loop helicity amplitudes for the process $q\\bar{q} rightarrow t\\bar{t}$ induced by KK gluon, using the spinor-helicity formalism. A minimal set of Feynman rules which are uniquely fixed by gauge invariance and the color representation of the KK gluon are derived and used in the calculation. Our results can be applied to a variety of models containing a massive color octet vector boson.
Helical dipole magnets are required in a project for the Relativistic Heavy Ion Collider (RHIC) to control and preserve the beam polarization in order to allow the collision of polarized proton beams. Specifications are for low current superconducting magnets with a 100 mm coil aperture and a 4 Tesla field in which the field rotates 360 degrees over a distance of 2.4 meters. A magnet meeting the requirements has been developed that uses a small diameter cable wound into helical grooves machined into a thick-walled aluminum cylinder.
Experiments are performed to investigate the single-phase flow and flow-boiling heat transfer augmentation in 3D internally finned and micro-finned helical tubes. The tests for single-phase flow heat transfer augmentation are carried out in helical tubes with a curvature of 0.0663 and a length of 1.15 m, and the examined range of the Reynolds number varies from 1000 to 8500. Within the applied range of Reynolds number, compared with the smooth helical tube, the average heat transfer augmentation ratio for the two finned tubes is 71% and 103%, but associated with a flow resistance increase of 90% and 140%, respectively. A higher fin height gives a higher heat transfer rate and a larger friction flow resistance. The tests for flow-boiling heat transfer are carried out in 3D internally micro-finned helical tube with a curvature of 0.0605 and a length of 0.668 m. Compared with that in the smooth ...
The possibility of controlling the radial electric field of toroidal plasmas by injecting high energy electrons along the reversible loss cone orbit of the helical magnetic traps is investigated. It is well known that the radial electric field plays an important role in the confinement improvement scenario especially in the low collisional regime under the physics picture of neoclassical theory. For this purpose, it is made clear that the most suitable particles are transit particles, which show a transition from helically trapped orbits to blocked ones. It is also found that a parallel AC electric field launched from outside assists this transition and makes it possible for particles to penetrate deeply into the plasma. In addition we clarify that the viscosity of the plasma coupled with the helical field configuration provide a bifurcation of plasma states and its stable solution results in confinement improvement. ...
The purpose of this study is to explain the unplanned longitudinal dose modulations that appear in helical tomotherapy (HT) dose distributions in the presence of irregular patient breathing....Full Text Available
Since the elucidation of the structure of double helical DNA, the construction of small molecules that recognize and react at specific DNA sites has been an area of considerable interest. In...Full Text Available
This thesis presents the work achieved to instrument the ATLAS software framework, ATHENA, with a library of tools and utensils for the physics analysis as well as the extraction of the jet energy scale using physics events (in-situ calibration). The software part presents the various components of the ATHENA framework which handles the simulated and reconstructed data flow as well as the different stages of this process, before and during the data taking. The building of a library of tools easing the reconstruction of physics objects, their association with Monte-Carlo particles and their API is then explained. The need for common language and collaboration-wide utensils is emphasised as it allows to share the workload of validating these tools and to get reproducible physics results. The analysis part deals with the implementation of a light jet energy scale calibration algorithm within the C++ framework. This calibration algorithm makes use of W ...
This document deals with the couplings between the Wboson and Z and gamma particles. WWZ and WW{gamma} vertex are predicted by the electroweak theory based on the symmetry group SU(2){sub L}*U(1){sub Y}, their existence is confirmed by the measurement of the production cross-section of W pairs at LEP. The effective values of the couplings are modified by the introduction of standard model particle loops at the vertex level, the impact on the coupling value is assessed to reach 10{sup -3}. These loops can also include beyond-the-standard-model particles, their impact is in the magnitude order of 10{sup -3} for most models. The fully description of these loops requires the values of 14 complex parameters whose measurement will give information about the existence of new particles. Nevertheless the number of events at LEP is not sufficient to measure all the parameters simultaneously. As a consequence the analysis is limited to the 3 most ...
We report a pH-dependent conformational transition in short, defined homopolymeric deoxyadenosines (dA15) from a single helical structure with stacked nucleobases at neutral pH to a double-helical,...Full Text Available
The non-natural pyrido[2,3-d]pyrimidine nucleoside F, which pairs preferentially with guanine (G) and adenine (A) within double-helical DNA, recognizes with high selectivity AT base pairs within triple-helical...Full Text Available
The reduction of four-vector and electromagnetic fields produced by spin-1 tachyons has been derived in terms of standard helicity representations of inhomogeneous Lorentz group, and the conditions for these superluminal electromagnetic fields to satisfy the Maxwell's field equations have been derived. 16 refs.
Helical tomotherapy presented many unique dosimetric challenges and solutions during the initial commissioning process, and some of them are presented. The dose calculation algorithm is convolution/superposition based. This requires that the energy fluence spectrum and magnitude be quantified. The methodology for doing so is described. Aspects of the energy fluence characterization that are unique to tomotherapy are highlighted. Many beam characteristics can be measured automatically by an included megavoltage computed tomography imaging system. This greatly improves data collection efficiency.
The contents of this report covers: (1) development of optimal geometries for crowned helical gears; (2) a method for their generation; (3) tooth contact analysis (TCA) computer programs for the analysis of meshing and bearing contact of the crowned helical gears; and (4) modelling and simulation of gear shaft deflection. The developed method for synthesis was used to determine the optimal geometry for a crowned helical pinion surface and was directed to localize the bearing contact and guarantee favorable shape and a low level of transmission errors. Two new methods for generation of the crowned helical pinion surface are proposed. One is based on the application of a tool with a surface of revolution that slightly deviates from a regular cone surface. The tool can be used as a grinding wheel or as a shaver. The other is based on a crowning pinion tooth surface with predesigned transmission errors. The ...
A helical cooling channel (HCC) has been proposed to quickly reduce the six-dimensional phase space of muon beams for muon colliders, neutrino factories, and intense muon sources. The HCC is composed of a series of RF cavities filled with dense hydrogen gas that acts as the energy absorber for ionization cooling and suppresses RF breakdown in the cavities. Magnetic solenoidal, helical dipole, and helical quadrupole coils outside of the RF cavities provide the focusing and dispersion needed for the emittance exchange for the beam as it follows a helical equilibrium orbit down the HCC. In the work presented here, two Monte Carlo programs have been developed to simulate a HCC to compare with the analytic predictions and to begin the process of optimizing practical designs that could be built in the near future. We discuss the programs, the comparisons with the analytical theory, and the prospects for a HCC ...
Helically coiled tubes of steam generators (SG) in FBR are boundaries between sodium and water/steam. Therefore, to assure the integrity of tubes, it is necessary to inspect the tubes nondestructively for in service or after a sodium-water reaction accident. In order to make it possible to conduct in-service inspection of SG tubes, we have studied on eddy current probes and probe inserting methods. As for the probe inserting method, IHI designed a fluid driving type which consists of a model probe and signal cable with float balls and driven by air pressure force. Presented in this paper is the authors' report, which describes the fluid driving type as an effective method to insert an eddy current probe into helically coiled tubes. The outline of the test results is as follows: 1. It was possible to insert the probe into 65 meter length helically coiled tubes. 2. We could detected, as anticipated, a defect (outer ...
Objective: To investigate the feasibility of low-dose single-slice helical CT in pulmonary CT scan and evaluate the clinical application. Methods: Thirteen cases were selected out of 132 cases, in which low-dose (50mAs) single-slice helical CT scan of chest was performed. This set of cases included 7 cases of multiple metastatic nodules; 3 of solitary pulmonary, nodule; and 3 of pulmonary patchy lesions. Regular dose (170mAs) CT scan was also performed on all those patients. The regular dose and low dose CT scan were compared on sensitivity of detecting the lesions; the performance in demonstrating the details of the abnormalities; and the capability of revealing the segmental bronchi as well. Results: The same number and size of the pulmonary nodules were revealed with scan modalities loaded with different doses. No significant difference in demonstrating the details of the nodules and the segmental bronchi was found between both modalities ...
The purpose of this work is to investigate the possible role of Helical CT defecography in pelvic floor disorders by comparing the results of the investigations with those of conventional defecography. The series analyzed consisted of 90 patients, namely 62 women and 28 men, ranging in age 24-82 years. They were all submitted to conventional defecography, and 18 questionable cases were also studied with Helical CT defecography. The conventional examination was performed during the 4 standard phases of resting, squeezing, Valsalva and straining; it is used a remote-control unit. The parameters for Helical CT defecography were: 5 mm beam collimation, pitch 2, 120 KV, 250 m As and 18-20 degrees gantry inclination to acquire coronal images of the pelvic floor. The rectal ampulla was distended with a bolus of 300 mL nonionic iodinated contrast agent (dilution: 3g/cc). The patient wore a napkin and was seated on the table, except ...
The exclusive electroproduction of ?0 mesons was studied with the HERMES spectrometer at the DESY laboratory by scattering 27.6 GeV positron and electron beams off a transversely polarized hydrogen target. Spin density matrix elements for this process were determined from the measured production- and decay-angle distributions of the produced ?0 mesons. These matrix elements embody information on helicity transfer and the validity of s-channel helicity conservation in the case of a transversely polarized target. From the spin density matrix elements, the leading-twist term in the single-spin asymmetry was calculated separately for longitudinally and transversely polarized ?0 mesons. Neglecting s-channel helicity changing matrix elements, results for the former can be compared to calculations based on generalized parton distributions, which are sensitive to the contribution of the total angular momentum of the quarks to the ...
The heat transfer a characteristics and friction factor in the horizontal double pipes of flat tubes with full length helical screw element of different twist ratio and helical screw inserts with different spacer length are investigated. Cold and hot water are used as working fluid in tube side and shell side respectively. The experiments covered a range of Reynolds numbers 5.7x102Re1.31x103. The effect of spacer length on the heat transfer augmentation and friction factor and the effect of twist ratio on heat transfer augmentation and friction factor have been presented separately. The study shows that, the Nusslet number (Nu) and friction factor (f) decrease with the increase of S or Y for flat tube. The comparison between the data of present plain circular with that of previous plain ci...
The purpose of this study was to compare 2 adaptive radiotherapy strategies with helical tomotherapy. A patient having mesothelioma with mediastinal nodes was treated using helical tomotherapy with pretreatment megavoltage CT (MVCT) imaging. Gross tumor volumes (GTVs) were outlined on every MVCT study. Two alternatives for adapting the treatment were investigated: (1) keeping the prescribed dose to the targets while reducing the dose to the OARs and (2) escalating the target dose while maintaining the original level of healthy tissue sparing. Intensity modulated radiotherapy (step-and-shoot IMRT) and 3D conformal radiotherapy (3DCRT) plans for the patient were generated and compared. The primary lesion and nodal mass regressed by 16.2% and 32.5%, respectively. Adapted GTVs and reduced plan...
Two Brucella fractions, the murein-linked fraction PI and the murein-free fraction SF, behave as in vitro adjuvants for primary anti-sheep erythrocyte responses: added to Mishell and Dutton-type cultures...Full Text Available
DEXD/H-box RNA helicases couple ATP hydrolysis to RNA remodeling by an unknown mechanism. We used x-ray crystallography and biochemical analysis of the human DEXD/H-box...Full Text Available
A protein evolution strategy is described by which double-stranded DNA fragments encoding defined E. coli protein secondary structural elements (α-helices, β-strands...Full Text Available
Roles of bumpy field on collisionless particle confinement in helical-axis heliotrons are investigated with the model magnetic field and particle orbit calculations in the Boozer coordinates. The mod-B{sub min} contours can be shifted in the major radius direction with the control of the bumpy field, where B{sub min} is the minimum value of |B| in the toroidal direction within one field period. The area of closed mod-B{sub min} contours is a useful measure to evaluate global collisionless particle confinement as long as the mod-B{sub min} contours connect toroidally. Negative value of ratio between the bumpy and the helicity components contributes to obtain the largest area of closed mod-B{sub min} contours for finite ratio between the toroidicity and the helicity components. The radial variation of the bumpy field attributes to realize a toroidally localized mod-B{sub min} structure, which is significantly effective to ...
A parallel bundle of transmembrane (TM) alpha-helices surrounding a central pore is present in several classes of ion channel, including the nicotinic acetylcholine receptor (nAChR). We have modeled...Full Text Available
BackgroundTo evaluate the performance of three different advanced treatment techniques on a group of complex paediatric cancer cases.MethodsCT...Full Text Available
To confirm that Mycobacterium tuberculosis chaperonin 10 (Cpn10) is secreted outside the live bacillus, infected macrophages were examined by electron microscopy. This revealed that...Full Text Available
The term ``dynamo'' means different things to the laboratory fusion plasma and astrophysical plasma communities. To alleviate the resulting confusion and to facilitate interdisciplinary progress, we pinpoint conceptual differences and similarities between laboratory plasma dynamos and astrophysical dynamos. We can divide dynamos into three types: 1. magnetically dominated helical dynamos which sustain a large scale magnetic field against resistive decay and drive the magnetic geometry toward the lowest energy state, 2. flow-driven helical dynamos which amplify or sustain large scale magnetic fields in an otherwise turbulent flow, and 3. flow-driven nonhelical dynamos which amplify fields on scales at or below the driving turbulence. We discuss how all three types occur in astrophysics whereas plasma confinement device dynamos are of the first type. Type 3 dynamos requires no magnetic or kinetic helicity of any kind. ...
ObjectiveThe aim of this study was to evaluate the utility of volume-rendered helical computerized tomography (CT) angiography focusing tracheostomy tube and innominate artery for...Full Text Available
This document presented the results of a full-scale pile load tests conducted on helix pile foundations supporting power transmission towers in northern Manitoba. The site conditions were described along with pile installation and the performance of the foundations. The pile load tests were carried out in 2 different soil conditions, notably soft to firm clays and stiff high plastic clays with silt varves. The performance of the helix pile foundations were examined under axial compressive and axial tension (uplift) loading conditions. The results of the compressive load tests were presented in the form of load settlement curves while the results of the uplift load tests were presented in the form of load displacement curves. Both types of load tests in soft or stiff clays showed the suitability of helical pile foundations for power transmission lines in northern Manitoba. The cylindrical shear failure mechanism controlled the behaviour of ...
The present report addresses several aspects of the free electron laser (FEL) and accelerator, including their features, potentials, mechanisms, beams emitted from undulator, FEL produced by helical mangnetic field, major problems with FEL, etc. In FEL, relativistic electron beams interact with an electromagnetic field with periodically changing intensity to produce coherent electromagnetic waves with variable wavelength. The capability of varying its wavelength represents the greatest advantage over conventional lasers. Any periodic magnetic field can serve as a wiggler. A wiggler can be used both in an amplifier and oscillator. A periodic magnetic field used may be either of a parallel type or of a helical type. The polarization of emitted beams depends on the shape of the magnet regardless of whether its field is parallel or helical. An equation is derived in the report which expresses the wavelength of an ...
SummaryDnaA initiates chromosomal replication in E. coli at a well regulated time in the cell-cycle. To determine how the spatial distribution of DnaA is related...Full Text Available
The primary mode of transmission of Helicobacter pylori, a human pathogen carried by more than half the population worldwide, is still unresolved. Some epidemiological data suggest...Full Text Available
Three-dimensional magnetohydrodynamic simulations are executed in a full toroidal geometry to clarify the physical mechanisms of the Internal Reconnection Event (IRE), which is observed in the spherical tokamak experiments. The simulation results reproduce several main properties of IRE. Comparison between the numerical results and experimental observation indicates fairly good agreements regarding nonlinear behavior, such as appearance of localized helical distortion, appearance of characteristic conical shape in the pressure profile during thermal quench, and subsequent appearance of the m=2/n=1 type helical distortion of the torus. (author)
By applying the mass, momentum, and angular momentum conservation laws and the maximum flow rate principle to swirling, effectively inviscid, incompressible flows in a circular tube with a sudden expansion and the direct-flow and reversed-flow Borda mouthpieces the dependence of the flow rate coefficient and mechanical energy losses on the radius ratio and nondimensional circulation is obtained. Several calculating approaches with potential and helical motion are introduced and investigated. In the case of helical motion, as the swirl decreases the axial core of the flow is found to close with a sudden change of the flow parameters.
Toroidal Alfven eigenmodes (TAE) destabilized by the pressure gradient of energetic alpha particles may expel the alpha particles before thermalization. TAE is important for tokamaks, and for helical systems (stellarators) as well. In CHS (compact helical system) TAE localized in the plasma core are destabilized when the plasma current is induced by co-injection of neutral beams. The observed TAE exhibits a ballooning nature. The internal structure of TAE was measured with a soft X-ray detector. The soft X-ray fluctuations level for TAE is too low to obtain the radial profiles of fluctuation intensities. (Tanaka, M.)
Abstract The creation of chirality on Earth and the development of chiral life have been discussed in this highlight. Convincing evidence for the introduction of chirality on Earth is still fragmentary. We believe that by a combination of chiral crystallization and formation of helical polymers with preferred chiral conformational structure is the key to this question. This concept of macromolecular asymmetry has inspired ideas and resulted in possible rules for how chiral life as we know it, could have been introduced. These investigations needed the understanding of the requirements for chiral crystallization, for the stereochemistry of the initial formation of helical polymers, the measurements of optical activity of solids and their coordination with the fundamentals of chirality. Spac...
Background: High-resolution computed tomography is the image procedure of choice in the evaluation of interstitial lung disease. Multidetector-row computed tomography provides the possibility of simultaneous reconstruction of thin and thick slices from the same raw data, acquired from one single series. Thus, it may be tempting to exclude the step-and-shoot series. Purpose: To compare high-resolution computed tomography (HRCT step-and-shoot) from single-slice CT (SSCT) and 16-channel multidetector CT (MDCT) in terms of visibility and motion artifacts, and to investigate whether thin images reconstructed from helical MDCT are equal to or better than conventional HRCT by SSCT in terms of visibility and motion artifacts. Material and Methods: 20 patients underwent HRCT step-and-shoot by SSCT (SSCT step-and-shoot) and MDCT (MDCT step-and-shoot), and a helical MDCT acquisition (MDCT helical). Images from four anatomical levels ...
Inherent to helical tomotherapy is a dose variation pattern that manifests as a 'ripple' (peak-to-trough relative to the average). This ripple is the result of helical beam junctioning, completely unique to helical tomotherapy. Pitch is defined as in helical CT, the couch travel distance for a complete gantry rotation relative to the axial beam width at the axis of rotation. Without scattering or beam divergence, an analytical posing of the problem as a simple integral predicts minima near a pitch of 1/n where n is an integer. A convolution-superposition dose calculator (TomoTherapy, Inc.) included all the physics needed to explore the ripple magnitude versus pitch and beam width. The results of the dose calculator and some benchmark measurements demonstrate that the ripple has sharp minima near p=0.86(1/n). The 0.86 factor is empirical and caused by a beam junctioning of the off-axis dose profiles ...
It is clarified that the so-caned 'helicity conservation law' is never the conservation equation of the helicity K itself', but is merely 'the time change rate equation of K', which is passively and resultantly determined by the mutually independent volume and surface integral terms. It is shown that since the total helicity K can never be conserved in the real experimental systems, the conjecture of the total helicity invariance is not physically available to real magnetized plasmas in an exact sense. The well-known relaxation theory by Dr. J. B. Taylor is clarified to be neither the variational principle nor the energy principle, but be merely a mathematical calculation, using the variational calculus in order to find the minimum magnetic energy solution from the set of solutions having the same value of K. With the use of auto-correlations for physical ...
Biosynthesis of hemoglobin and some of its electrophoretic fractions in red cells of peripheral blood and spleen of irradiated (650 R) rats has been studied. Hemoglobin synthesis is found to be most drastically inhibited in the first and second fractions on the first and eighth days after irradiation and in the fifth and sixth fractions on the eighth day (less expressed). The synthesis is restored on the twelfth day, the process under study proceeding more slowly in the above-mentioned fractions than in others. In the course of radiation sickness, the biosynthesis of certain hemoglobin fractions varies differently in the hemoglobin-synthesizing cells of peripheral blood than in the cells of spleenic erythroid series.
BackgroundThe use of fractionated stereotactic radiotherapy (fsrt) has evolved with technical advances in noninvasive immobilization, radiation delivery, and image guidance....Full Text Available
The heat transfer a characteristics and friction factor in the horizontal double pipes of flat tubes with full length helical screw element of different twist ratio and helical screw inserts with different spacer length are investigated. Cold and hot water are used as working fluid in tube side and shell side respectively. The experiments covered a range of Reynolds numbers 5.7 x 10{sup 2} {<=} Re {<=} 1.31 x 10{sup 3}. The effect of spacer length on the heat transfer augmentation and friction factor and the effect of twist ratio on heat transfer augmentation and friction factor have been presented separately. The study shows that, the Nusslet number (Nu) and friction factor (f) decrease with the increase of S or Y for flat tube. The comparison between the data of present plain circular with that of previous plain circular tube showed a good agreement between them but the data of present plain flat tube showed a higher in heat ...
The great advantage of the helical ionization cooling channel (HCC) is its compact structure that enables the fast cooling of muon beam 6-dimensional phase space. This compact aspect requires a high average RF gradient, with few places that do not have cavities. Also, the muon beam is diffuse and requires an RF system with large transverse and longitudinal acceptance. A traveling wave system can address these requirements. First, the number of RF power coupling ports can be significantly reduced compared with our previous pillbox concept. Secondly, by adding a nose on the cell iris, the presence of thin metal foils traversed by the muons can possibly be avoided. We show simulations of the cooling performance of a traveling wave RF system in a HCC, including cavity geometries with inter-cell RF power couplers needed for power propagation.
The physics of density limit phenomena in toroidal helical plasmas based on an analytic point model of toroidal plasmas is discussed. The combined mechanism of the transport and radiation loss of energy is analyzed, and the achievable density is derived. A scaling law of the density limit is discussed. The dependence of the critical density on the heating power, magnetic field, plasma size and safety factor in the case of L-mode energy confinement is explained. The dynamic evolution of the plasma energy and radiation loss is discussed. Assuming a simple model of density evolution, of a sudden loss of density if the temperature becomes lower than critical value, then a limit cycle oscillation is shown to occur. A condition that divides the limit cycle oscillation and the complete radiation collapse is discussed. This model seems to explain the density limit oscillation that has been observed on the W7-AS stellarator. (author)
Measurements of smoke and NO emissions from a direct-injection diesel engine have shown that they are indeed influenced by inlet port design, even though the swirl numbers for the ports may be identical. The swirl numbers of the three ports used (tangential port, helical port and helical port with masked valve) were measured on a steady-state test rig using a paddle-wheel anemometer and impulse swirl meter. Flow measurements were carried out under motoring conditions with a constant-temperature, hot-wire anemometer. Is was possible to find a correlation between flow data and exhaust data as far as the in-cylinder air motion over a certain time interval is concerned.
Active contrast material extravasation can be recognized with conventional CT scanners, though it has been considered a rare finding. Helical CT seems to increase the detection rate and especially to boost the radiologist's confidence in this diagnosis. Though active bleeding is defined in severely-injured subjects requiring urgent intervention and may be associated with findings of hypovolaemic shock, it should not be considered itself as a negative prognostic factor. Contrast extravasation is due to ongoing hemorrhage and its detection is critical for urged treatment. Accurate anatomical location permits to choose surgical management or transcatheter embolization and thus decreases time consumption for precis e bleeding site identification.
This is a report of extraction and identification of 1-O-alkyl glycerol present in the dried leaves of Bauhinia scandens. Fifty percent aqueous ethanolic extract of the plant at room temperature was fractionated over petroleum ether and diethyl ether. The diethyl ether soluble fraction showed positive bioactivity in Brine Shrimp bioassay. Isolation and purification of the active principle was subsequently done from diethyl ether fraction. The diethyl ether fraction was separated into acidic and neutral part. The acid free fraction was screened to be positive in Brine Shrimp bioassay. The NMR spectra (in CDCl3) indicated the probability of its lipoidal nature. The total lipid fraction was resolved into neutral, glyco, and phospho-lipids by column chromatography. Only the neutral fraction sh...
In the framework of the equivalence theorem the one-loop helicity amplitudes and cross section for the double Higgs production process {gamma}{gamma}{yields}HH are calculated. It is shown that the cross section is measurable at TeV {gamma}{gamma} colliders and is marginally sensitive to the triple-Higgs variation. (orig.).
In the framework of the equivalence theorem the one-loop helicity amplitudes and cross section for the double Higgs production process #gamma##gamma##->#HH are calculated. It is shown that the cross section is measurable at TeV #gamma##gamma# colliders and is marginally sensitive to the triple-Higgs variation. (orig.).
The emission of Cerenkov radiation by tachyons has been examined by using the reduced expansions of superluminal electromagnetic fields in terms of standard helicity representation of Poincare group. It has been shown that the tachyons emit Cerenkov radiation through their coupling only with subluminal electromagnetic fields and that a charged tachyon can emit Cerenkov radiation only in the media in which it travels with a velocity lower than that of light while in the usual medium in which its velocity is more than that of light, it will never emit Cerenkov radiation.
Lorentz invariant theory of second quantization of superluminal electromagnetic fields has been constructed in purely group theoretical manner by using the reduced expansion of four-vector fields for imaginary mass system in terms of standard helicity representations of Poincare group. It has been shown that the usual relationship of spin and statistics need not be inverted for Lorentz invariance of the theory of spin-1 tachyons. 15 refs.
Lorentz invariant theory of second quantization of superluminal electromagnetic fields has been constructed in purely group theoretical manner by using the reduced expansion of four-vector fields for imaginary mass system in terms of standard helicity representations of Poincare group. It has been shown that the usual relationship of spin and statistics need not be inverted for Lorentz invariance of the theory of spin-1 tachyons. (author).
The polarization characteristics of spontaneous radiation from relativistic electrons moving through helical and planar wiggler fields are evaluated for imperfect beam injection. Maximum coherent gain in free-electron laser systems are seen to occur in optical fields having these polarization characteristics rather than those of the wiggler magnets. Coupling coefficients for an electron beam skewed at an angle to the optical mode are presented.
To analyze the enhancement patterns and morphology of peripheral cholangiocar-cinomas (CCs), as seen on three-phase helical CT. Three-phase helical CT scans of 25 cases of 24 patients with pathologically-proven CCs were retrospectively reviewed. After intravenous administration of contrast media, scans of the hepatic arterial phase (HAP) were obtained at 30 seconds, of the portal venous phase (PVP) at 70 seconds, and of the delayed phase (DP) at 3 minutes. Linear, dense, marginal enhancement was seen in 17 CCs (68%), mainly on HAP images (64%) while thick, band-like, peripheral enhancement was seen in 18 (72%), on either PVP (52%) or DP (44%). Internal enhancement was observed in 23 CCs (92%) on PVP (68%) and/or DP (88%), and 19 CCs (76%) among them showed incomplete enhancement of stippled and/or septated patterns. Most (76%) were seen throughout all three phases to be hypoattenuating, as compared to the surrounding parenchyma. On HAP, ...
The evaluate the signs of aortic intramural hematoma with helical CT and the diagnostic role of this technique in patients with this condition. It was reviewed the CT findings of 396 patients submitted to emergency examinations for suspected aortic dissection from 1995 to 1999. Only 18 patients (6 women and 12 men) had CT signs of aortic intramural hematoma. Helical CT studies were carried out with the following parameters: slice thickness 10 mm, reconstruction index 10, feed 1.5 mm, conventional algorithm with minimum values of 130 kV and 125mA. All patients were examined with dynamic contrast-enhanced CT, before and after a power injection of 130 mL ionic contrast material. It was studied: hematoma localization and longitudinal extension; thickness and density of aortic wall; presence and location of intimal calcifications; integrity of intimal wall; hemo mediastinum and/or hemo thorax. Aortic wall thickening appeared as a high density ...
This contribution deals with identification of fractional-order dynamical systems. System identification, which refers to estimation of process parameters, is a necessity in control theory. Real processes are usually of fractional order as opposed to the ideal integral order models. A simple and elegant scheme of estimating the parameters for such a fractional order process is proposed. This method employs fractional calculus theory to find equations relating the parameters that are to be estimated, and then estimates the process parameters after solving the simultaneous equations. The said simultaneous equations are generated and updated using particle swarm optimization (PSO) technique, the fitness function being the sum of squared deviations from the actual set of observations. The data used for the calculations are intentionally corrupted to simulate real-life conditions. Results show that the ...
In proteomics, one-dimensional (1D) SDS-PAGE is widely used for protein fractionation prior to mass spectrometric analysis to enhance dynamic range of analysis and to improve identification...Full Text Available
A new analysis is presented which links real volume fractions, relaxation rates, and intracompartmental exchange rates directly with apparent volume fractions and relaxation rates obtained from biexponential...Full Text Available
The results of a search for fractionally charged particles produced in e/sup +/e/sup -/ annihilation at 29 GeV/c/sup 2/ are discussed. Results from cosmic-ray searches for fractionally charged particles, tachyons, and massive particles using the same detector are also presented.
The effects of homologous plasma HDL and VHDL fractions on established atherosclerotic lesions were studied in cholesterol-fed rabbits. Atherosclerosis was induced by feeding the animals a 0.5% cholesterol-rich...Full Text Available
The soluble subcellular fraction of a chlB mutant contains an inactive precursor form of the molybdoenzyme nitrate reductase, which can be activated by the addition to the soluble fraction of protein...Full Text Available
Experiments were conducted to determine the dose response of rat bladder urothelium to a range of different single and fractionated intravesicular doses of the carcinogen, N-methyl-N-nitrosourea (MNU)....Full Text Available
The structural properties of brain extracellular space (ECS) are summarised by the tortuosity (λ) and the volume fraction (α). To determine if these two parameters were independent,...Full Text Available
BACKGROUND: Accurate estimation of left ventricular ejection fraction (LVEF) has assumed great significance in the era of automatic implantable cardioverter defibrillators (AICDs), and a low EF may...Full Text Available
The finest particle size fractions ({le} 25 {mu}m) in four fly ash samples from fluidised bed combustion of three biomass based fuels and a municipal solid waste fuel were size separated using a centrifugal SPLITT fractionation cell. The ashes were separated into different size fractions and the cadmium concentration, partition and speciation in each separated fraction were then investigated in relation to their possible leaching. The fractionation was evaluated by environmental scanning electron microscopy, which also provided indications of the associations between Cd and other main elements on the particles through the use of X-ray fluorescence mapping. The total concentration of Cd in each fraction was determined by AAS analysis which showed different dependence on the ash particle size in the case of biomass or waste fuels. In addition, the speciation of Cd ...
When a certain void fraction value is reached in the two-phase flow regime, a problem occurs in the COBRA-EN code. This problem was observed in the drift-flux model option and interrupts code execution. Two solutions are proposed to solve the problem.
Hexane extract of licorice (Glycyrrhiza glabra L.) roots was obtained and investigated. Hydrocarbons, sterol ethers, triacylglycerides, free fatty acids, and free sterols were identified. The extract contains 70% neutral and 30% polar lipids. It is established that the lipid fraction of licorice roots is more effective than the analogous fraction of rosehip oil in stimulating the reparative regeneration of skin. In addition, this fraction also exhibits pronounced antiinflammatory and antiulcer effects, while being virtually nontoxic. Based on these results, the lipid fraction of licorice roots can be recommended as a parent substance for creating effective preparations in various medicinal forms.
System identification is a necessity in control theory. Classical control theory usually considers processes with integer order transfer functions. Real processes are usually of fractional order as opposed to the ideal integral order models. A simple and elegant scheme is presented for approximation of such a real world fractional order process by an ideal integral order model. A population of integral order process models is generated and updated by PSO technique, the fitness function being the sum of squared deviations from the set of observations obtained from the actual fractional order process. Results show that the proposed scheme offers a high degree of accuracy.
In this note, we derive from Anstee's fractional $(g,f)$-factor theorem a similar characterization for the property of all fractional $(g,f)$-factors. Let $afractional $[a, b]$-factors if the minimum degree is at least $\\delta(G)\\geq \\frac{1}{4a}((a+b-1)^2+4b)$ and every pair of non-adjacent vertices has cardinality of the neighborhood union at least $bn/(a + b)$. This lower bounds are sharp.
This report contains a set of nomographs which can be used to estimate the average annual solar fraction for solar space and water heating at a large number of DOD facilities. The solar fraction estimated from the nomograph is in close agreement with F-Chart 3.0 and allows for variation of the following parameters: annual load, collector area, collector transmittance-absorptance coefficient, and collector overall loss coefficient.
A set of nomographs is presented which can be used to estimate the average annual solar fraction for solar space and water heating at a large number of DOD facilities. The solar fraction estimated from the nomograph is in close agreement with F-Chart 3.0 and allows for variation of the following parameters: annual load, collector area, collector transmittance-absorptance coefficient, and collector overall loss coefficient.
A set of nomographs is provided which can be used to estimate the average annual solar fraction for solar space and water heating at a large number of DOD facilities. The solar fraction estimated from the nomograph is in close agreement with F-Chart 3.0 and allows for variation of the following parameters: annual load, collector area, collector transmittance-absorption coefficient, and collector overall loss coefficient.
The production of X-ray radiation with a high degree of circular polarization constitutes an important goal at XFEL facilities. A simple scheme to obtain circular polarization control with crossed undulators has been proposed so far. In its simplest configuration the crossed undulators consist of pair of short planar undulators in crossed position separated by an electromagnetic phase shifter. An advantage of this configuration is a fast helicity switching. A drawback is that a high degree of circular polarization (over 90%) can only be achieved for lengths of the insertion devices significantly shorter than the gain length, i.e. at output power significantly lower than the saturation power level. The obvious and technically possible extension considered in this paper, is to use a setup with two or more crossed undulators separated by phase shifters. This cascade crossed undulator scheme is distinguished, in performance, by a fast helicity ...
Experiments were conducted to confirm the isotropic spatial resolution of multislice CT with a 0.5 mm slice thickness. Isotropic spatial resolution means that the spatial resolution in the transaxial plane (X-Y plane) and that in the longitudinal direction (Z direction) are equivalent. To obtain point spread function (PSF) values in the X-Y-Z directions, three-dimensional voxel data were obtained by helical scanning of a bead phantom. The modulation transfer function (MTF) values were then obtained by three-dimensional Fourier transform of the PSF. Evaluation of the spatial resolution in the X-Y-Z directions by the MTF values showed that the spatial resolution in the Z direction does not depend on the reconstruction kernel used. It was also found that the spatial resolution in the Z direction, as compared with that in the X-Y plane, is superior with the standard kernel for the abdomen and is inferior with the high-definition kernel for the ears/bones. By performing ...
Using the ammonia (NH3) plasma generated by a helical antenna surrounded by two magnetic coils, the transition of the discharge mode from low-density plasma to high-density one was observed. At the transition, the emission intensities from the H atoms and NH radicals especially increased in the optical emission spectroscopy, while the intensities of the other emission lines also increased abruptly. The nitridation of gallium arsenide (GaAs) surface was performed using the high-density NH3 plasma, and the properties of the nitrided surface layer were compared with those nitrided by high-density N2 plasma using the same apparatus. From the spectroscopic ellipsometry measurements, the thickness of the nitrided layer was estimated to be 16-18 nm, while that by N2 was 3-4 nm. From the Ga 3d spectra, the contamination with oxygen in the nitridation layer by NH3 plasma was less than that by N2 plasma.
Pfirsch-Schlueter (P-S) current is an inherent property of a finite pressure toroidal equilibrium of tokamak and stellarator. However, it was pointed out recently (V.D. Pustovitov, Nuclear Fusion 36 (1996) 583) that the P-S current would be suppressed completely if the external vertical field could be adjusted to satisfy the condition {omega}=<{omega}> in an l=3 stellarator. Here {omega}=<B tilde{sup 2}>/B{sub 0}{sup 2}-2{epsilon} cos{theta}, l is a pole number, |B tilde| the vacuum helical magnetic field, B{sub 0} the toroidal field, {epsilon} the inverse aspect ratio, {theta} the poloidal angle and <...> denotes the average over the toroidal angle. An example of such a stellarator equilibrium is presented in this paper. For this stellarator equilibrium, behavior of rotational transform and Boozer magnetic spectrum is clarified when the pressure is increased. Both formation of helical magnetic axis and ...
An automatic loading roller for transmitting torque in traction drive devices in manipulator arm joints includes a two-part camming device having a first cam portion rotatable in place on a shaft by an input torque and a second cam portion coaxially rotatable and translatable having a rotating drive surface thereon for engaging the driven surface of an output roller with a resultant force proportional to the torque transmitted. Complementary helical grooves in the respective cam portions interconnected through ball bearings interacting with those grooves effect the rotation and translation of the second cam portion in response to rotation of the first. 14 figs.
This patent describes an automatic loading roller for transmitting torque in traction drive devices in manipulator arm joints includes a two-part camming device having a first cam portion rotatable in place on a shaft by an input torque and a second cam portion coaxially rotatable and translatable having a rotating drive surface thereon for engaging the driven surface of an output roller with a resultant force proportional to the torque transmitted. Complementary helical grooves on the respective cam portions interconnected through ball bearings interacting with those grooves effect the rotation and translation of the second cam portion in response to rotation of the first.
The tube bundle arrangement is suitable as reheating section of a steam generator in combination with a gas-cooled reactor. For any high-temperature section with a straightline type tube bundle, there is one inlet and one outlet collecting main; these two are arranged one opposite to the other and diametrically to the tube bundle. There are a number of lines from the inlet collecting main to the outlet collecting main; these lines are arranged axially one on top of the other and run around the tube bundle helically several times. (GL) 891 GL/GL 892 MB.
Purpose of this work is to investigate the role of Helical CT and the usefulness of three-dimensional (3D) imaging for pre-operative planning and follow-up of reconstructive maxillofacial surgery with alloplastic material in neoplastic disease involving this region. From 1996 to 1999 eleven patients were examined with Helical CT and 3D images for planning of maxillofacial plastic and reconstructive surgery for advanced cancer of this anatomically complex region. A 3D-modulated titanium mesh (100%) or micro nets was used to rebuild the anterior surface of maxillary bone and the orbital floor. The mesh was cut to the appropriate size and shape and curved where necessary. Within the residual sinusal cavity a siliconed filling was used surmounting an acrylic prosthesis with dental arch to rebuild the palate. A rehydrated bovine pericardium was affixed and moduled on the borders in two cases only. Three-dimensionally reconstructed CT images were ...
The emission of Cerenkov radiation by tachyons has been examined by using the reduced expansions of superluminal electromagnetic fields in terms of standard helicity representation of Poincare group. It has been shown that the tachyons emit Cerenkov radiation through their coupling only with subluminal electromagnetic fields and that a charged tachyon can emit Cerenkov radiation only in the media in which it travels with a velocity lower than that of light while in the usual medium in which its velocity is more than that of light, it will never emit Cerenkov radiation. (author).
An algorithm is proposed which treats the ECH generated potential in a self-consistent way, by extending the Monte-Carlo Fokker-Planck method used by Murakami [S. Murakami et al., Proc. 17th IAEA Fusion Energy Conference, Yokohama, 1998 (International Atomic Energy Agency, Vienna, in press), paper CN-69/TH2/1]. The additional physics is expected to influence the transport of both thermal and suprathermal electrons in a helical toroidal system. (author)
The purpose of this paper is to report the personal experience with helical CT evaluation of hepatocellular carcinoma treated with various percutaneous interventional procedures. From December 1996 to September 1998 it were examined with helical CT 41 patients (73 nodules in all) with hepatocellular carcinoma treated with percutaneous ablation therapies: conventional ethanol injection in 18 subjects (31 nodules), one-shot ethanol injection 3 (8 nodules), radiofrequency thermal ablation in 16 (25 nodules), and combined chemo embolization and ethanol injection in 4 (9 nodules). CT performed was 4-27 days after the last session, acquiring biphasic volumetric images in 14 patients and triphasic volumetric images in 27. A second treatment with subsequent CT study was performed for 28 lesions; 15 underwent 3 serial studies and 6 underwent 4 studies. Compared with pretreatment findings, the diameter was unchanged in 62% of the nodules and increased in ...
The main purpose of this work is to report the personal experience with addition of contrast-enhanced multiphase helical CT to unenhanced CT (Lipiodol CT) in the evaluation of patients with hepatocellular carcinoma treated with chemoembolization and to analyze the present role of oily agent CT. It has been retrospectively reviewed the examinations of 42 consecutive patients submitted to globla chemoembolization over a 2-year period. CT was performed 18-30 days after the treatment. The Lipiodol CT study was carried out with volume acquisitions. It has been considered as nodules all well-defined areas with dense oily agent uptake; uptake itself was classified as: 0=absent, I=lower tha 10% of the tumor volume; II=lower than 50%, III=50%, IV=homogeneous. Contrast-enhanced helical CT was performed with the 2-phase technique in 28 patients and with the 3-phase technique in 14; it has been considered as nodules all well-defined and relatively ...
By means of a global mode analysis of ideal MHD modes for Mercier-unstable equilibria in a planar axis L=2/M=10 heliotron/torsatron system with an inherently large Shafranov shift, the conjecture from local mode analysis for Mercier-unstable equilibria given in [N. Nakajima, Phys. Plasmas 3, 4556 (1996)] has been confirmed and the properties of pressure-driven modes, namely, ballooning modes and interchange modes, inherent to such three-dimensional systems have been clarified. The change of the local magnetic shear due to the Shafranov shift, which is related to toroidicity, reduces the field line bending stabilizing effects on ballooning modes. According to the degree of the reduction of the local magnetic shear by the Shafranov shift, the Mercier-unstable equilibria are categorized into toroidicity-dominant (strong reduction) and helicity-dominant (weak reduction) Mercier-unstable equilibria. Since the local magnetic curvature due to helicity ...
Several fast neutral pressure gauges have been installed on NSTX [National Spherical Torus Experiment] to measure the vessel and divertor pressure during inductive and coaxial helicity injected (CHI) plasma operations. Modified, PDX [Poloidal Divertor Experiment]-type Penning gauges have been installed on the upper and lower divertors. Neutral pressure measurements during plasma operations from these and from two shielded fast Micro ion gauges at different toroidal locations on the vessel mid-plane are described. A new unshielded ion gauge, referred to as the In-vessel Neutral Pressure (INP) gauge is under development.
In several recent papers on entanglement in relativistic quantum systems and relativistic Bell's inequalities, relativistic Bell-type two-particle states have been constructed in analogy to nonrelativistic states. These constructions do not have the form suggested by relativistic invariance of the dynamics. Two relativistic formulations of Bell-type states are shown for massive particles, one using the standard Wigner spin basis and one using the helicity basis. The construction hinges on the use of Clebsch-Gordan coefficients of the Poincare group to reduce the direct product of two unitary irreducible representations (UIRs) into a direct sum of UIRs.
We present an application that automatically writes the Helas library corresponding to the Feynman rules of any Lagrangian, renormalizable or not, in quantum field theory. The code, written in Python, takes the Universal FeynRules Output as an input and produces the complete set of routines (wave-functions and amplitudes) that are needed for the computation of Feynman diagrams at leading as well as at higher orders. The representation is language independent and outputs in Fortran, C++, Python are currently available. A few key sample applications implemented in the MadGraph5 framework are presented.
The magnetic structure of the cubic compound CeAl{sub 2} is incommensurate and double-k. The moments on the two Ce sites describe two elliptical helices of opposed chiralities and lie in the (11-bar0) plane, with their Fourier components m{sup k} close to the [111] direction. Recent symmetry considerations, including for the first time the inversion center of the crystal, have reduced the number of parameters of this structure and have underlined the existence of a phase difference between the projections m{sub x}{sup k}, m{sub y}{sup k} and m{sub z}{sup k} of m{sup k}. Up to now, although many neutron investigations have been carried out on CeAl{sub 2} single crystals, no set of magnetic intensities was available which was large and good enough to check whether this phase difference exists or not. We have measured such a set of data, taking great care of the instrumental resolution in order to avoid unwanted contributions to the intensities from other domains. As ...
The magnetic structure of the cubic compound CeAl_2 is incommensurate and double-k. The moments on the two Ce sites describe two elliptical helices of opposed chiralities and lie in the (11-bar0) plane, with their Fourier components m"k close to the [111] direction. Recent symmetry considerations, including for the first time the inversion center of the crystal, have reduced the number of parameters of this structure and have underlined the existence of a phase difference between the projections m_x"k, m_y"k and m_z"k of m"k. Up to now, although many neutron investigations have been carried out on CeAl_2 single crystals, no set of magnetic intensities was available which was large and good enough to check whether this phase difference exists or not. We have measured such a set of data, taking great care of the instrumental resolution in order to avoid unwanted contributions to the intensities from other domains. As the magnetic form factor of the #GAMMA#_7 ground ...
Objective: To investigate the value ofMSCT in observing the direct findings of hilar cholangiocarcinoma1Methods Multislice helical CT studies were performed on the upper abdomen in 19 consecutive patientswith painless jaundice1 Precontrast and dynamic contrast enhanced (25 s phase and 60 s phase) scanswere conducted, and 3D imageswere reconstructed using enhanced raw data in 15 cases1 The direct CT findings of hilar cholangiocarcinoma were studied by three radiologists respectively in a 32scale strategy1 The morphological features and extension of bile duct involvement by hilar cholangiocarcinoma were analyzed1 All the 19 caseswere pathologically p roved as hilar cholangiocarcinoma by surgery (15 cases) and ERCP ( 4 cases) 1 Results The direct findings and extension of hilar cholangiocarcinoma could be demonstrated in 14 out of 15 3D reconstruction images, 8 out of 19 in 25 s phase, and 7 out of 19 in 60 s phase of contrast enhancement scans, respectively ( P < ...
Acute thoracic aortic injuries account for up to 10-20% of fatalities in high-speed deceleration road accidents and have an estimated immediate fatality rate of 80-90%. Untreated survivors to acute trauma (10-20%) have a dismal prognosis: 30% of them die within 6 hours, 40-50% die within 24 hours, and 90% within 4 months. It was investigated the diagnostic accuracy of Helical Computed Tomography (Helical CT) in acute traumatic injuries of the thoracic aorta, and the role of this technique in the diagnostic management of trauma patients with a strong suspicion of aortic rupture. It was compared retrospectively the chest Helical CT findings of 256 trauma patients examined June 1995 through August 1999. Chest Helical CT examinations were performed according to trauma score, to associated traumatic lesions and to plain chest radiographic findings. All the examinations were performed with no intravenous ...
DOI: http://dx.doi.org/10.1103/PhysRevC.78.045209 The helicity amplitudes of the electroexcitation of the Roper resonance are extracted for 1.7 < Q2 < 4.5 GeV2 from recent high precision JLab-CLAS cross section and longitudinally polarized beam asymmetry data for pi+ electroproduction on protons at W=1.15-1.69 GeV. The analysis is made using two approaches, dispersion relations and a unitary isobar model, which give consistent results. It is found that the transverse helicity amplitude A_{1/2} for the gamma* p -> N(1440)P11 transition, which is large and negative at Q2=0, becomes large and positive at Q2 ~ 2 GeV2, and then drops slowly with Q2. The longitudinal helicity amplitude S_{1/2}, which was previously found from CLAS ep -> eppi0,enpi+ data to be large and positive at Q2=0.4,0.65 GeV2, drops with Q2. Available model predictions for gamma* p -> N(1440)P11 allow us to conclude that these ...
Aim of this retrospective study was to assess the capability of contrast-enhanced helical computerised tomography (CT) in sigmoid diverticulitis, especially relative to selection of the appropriate treatment. The findings of 41 patients were reviewed from 1998 to 1999 June. Contrast-enhanced helical CT is the imaging modality of choice in assessing mild or severe acute diverticulitis because it provides useful information for appropriate treatment planning in the emergency setting. This technique is most useful in questionable cases and in patients with suspected severe diverticulitis where a choice must be made between different treatment options. [Italian] Scopo di questo studio retrospettivo e' illustrare i molteplici aspetti radiologici della flogosi diverticolare sigmoidea con tomografia computerizzata (TC) spirale, con specifico riguardo alle implicazioni terapeutiche che scaturiscono dall'analisi e dal confronto dei ...
Natural bone consists of hard nanostructured hydroxyapatite (HA) in a nanostructured protein-based soft hydrogel template (ie, mostly collagen). For this reason, nanostructured HA has been an intriguing coating material on traditionally used titanium for improving orthopedic applications. In addition, helical rosette nanotubes (HRNs), newly developed materials which form through the self-assembly process of DNA base pair building blocks in body solutions, are soft nanotubes with a helical architecture that mimics natural collagen. Thus, the objective of this in vitro study was for the first time to combine the promising attributes of HRNs and nanocrystalline HA on titanium and assess osteoblast (bone-forming cell) functions. Different sizes of nanocrystalline HA were synthesized in this study through a wet chemical precipitation process following either hydrothermal treatment or sintering. Transmission electron microscopy images showed that ...
New measuring methods are developed and are tested with the small reactor simulator MIDAS (Mini Dodewaard ASsembly). The purpose of this work is to be able to measure accurately as many different properties of the flow as possible in the coming bigger simulator SIDAS (Simulated Dodewaard ASsembly). In SIDAS the flow around a fuel assembly of the Dutch Dodewaard reactor will be simulated. An extensive evaluation of the gamma detection system showed that the detection system could be simplified strongly. The simplified system is used to measure the radial and axial distribution of the void fraction in the core of MIDAS for three different operating conditions. Two new measuring methods have been developed and tested. A method to estimate the probability density of the void fraction in time. Due to the nonlinear relation between transmission and void fraction the determined average value of the void ...
Radiographic images generated by the real-time neutron radiography system (RTNR) are analyzed by customized image processing software of the determination of instantaneous void fraction distribution. The cross-sectional averaged axial void fraction profiles and the two-dimensional void fraction profiles are determined simultaneously for each image. Various flow regimes are generated to determine if the RTNR system can accurately predict the void distribution in the radial, axial, and temporal coordinates. The results show the RTNR system correctly determines the void fraction distribution for each flow regime; however, accuracy decreases with decreasing void fraction. For net water thicknesses > 1.0 cm, the accuracy decreases with increasing water thickness due to the extreme sensitivity of thermal neutron interactions with light water. Heavy water is a more suitable fluid than ...
The purpose of this work is to investigate the possible role of Helical CT defecography in pelvic floor disorders by comparing the results of the investigations with those of conventional defecography. The series analyzed consisted of 90 patients, namely 62 women and 28 men, ranging in age 24-82 years. They were all submitted to conventional defecography, and 18 questionable cases were also studied with Helical CT defecography. The conventional examination was performed during the 4 standard phases of resting, squeezing, Valsalva and straining; it is used a remote-control unit. The parameters for Helical CT defecography were: 5 mm beam collimation, pitch 2, 120 KV, 250 m As and 18-20 degrees gantry inclination to acquire coronal images of the pelvic floor. The rectal ampulla was distended with a bolus of 300 mL nonionic iodinated contrast agent (dilution: 3g/cc). The patient wore a napkin and was seated on the table, except ...
Full text.Sediments are the ultimate sink of trace elements. The total metal analysis may only give information concerning possible enrichment of metals. The analysis of metal partitioning in the different chemical components of sediments (exchangeable, carbonate, easily reducible, moderately reducible, organic and residual); give a detailed information on the way in which these metals are bound to sediments, their mobilization capacity and their ability to affect water quality under different environmental conditions. The studied river basin is dominated by limestone formation, the enrichment of metals in the carbonate sediment fraction is a high probability. The objective of the study was to determine the percentage of the total metal content (Fe, Mn, Zn, Cu and Pb) in the six chemical fractions of the bed load sediments of Nahr-Ibrahim river during the dry season and verify the role of carbonate for metal sediment deposition. Bed load ...
A state of the art review of two-phase void fraction models in smooth horizontal tubes is provided and a probabilistic two-phase flow regime map void fraction model is developed for refrigerants under condensation, adiabatic, and evaporation conditions in smooth, horizontal tubes. Time fraction information from a generalized probabilistic two-phase flow map is used to provide a physically based weighting of void fraction models for different flow regimes. The present model and void fraction models in the literature are compared to data from multiple sources including R11, R12, R134a, R22, R410A refrigerants, 4.26-9.58 mm diameter tubes, mass fluxes from 70 to 900 kg/m{sup 2} s, and a full quality range. The present model has a mean absolute deviation of 3.5% when compared to the collected database. (author)
We compared the values of the myocardial thickness and the left ventricle diameters measured with MRI and echocardiography. The ejection fraction was compared in MRI and ventriculography. 34 patients with different heart dysfunctions were examined with MRI (FISP 2D sequence). 26 of them were also studied by echocardiography and 20 by biplane cine-ventriculography. The enddiastolic thicknesses of the left ventricular postero-lateral wall and of the septum interventriculare were measured on short axis images. An ellipsoidal modell was used for volume calculation and ejection fraction. Correlation of MRI values of thickness and ejection fraction with echocardiographi and angiographi showed r>0,8. As known for 1.56 T Imagers, the myocardial thickness in MRI was underestimated compared to echocardiography (1.4 mm#+-#1.7). The ejection fraction was underevaluated compared to ventriculography ...
Maytenus ilicifolia Mart. ex Reissek is traditionally used in Brazil for treatment of gastric ulcers. Here we report the phytochemical investigation of an ethanol extract of M. ilicifolia leaves (EEMIL) aiming at the isolation of constituents which were used as chemical markers to monitor an activity-guided fractionation of a lyophilized aqueous extract of M. ilicifolia leaves (LAEMIL). From EEMIL, four flavonoids were isolated, namely the tri-flavonoid glycosides mauritianin (1), trifolin, (2) hyperin (4), and epi-catechin (5). Fractionation of LAEMIL led to 5 fractions which afforded the tetra-glycoside kaempferol derivative (3), and galactitol (6). LAEMIL and its fractions were evaluated in rats for their effects on gastric secretion volume and pH. HPLC (High Performance Liquid Chromatography) analysis revealed that only fractions containing the tri- and tetra-flavonoid ...
Tar sand bitumen is petroleum-based ultra-heavy oil, and has a great amount of reserve like coal. However, there are still a lot of problems for its highly effective utilization. This paper discusses whether the light components in bitumen show independent behavior during the thermal cracking of heavy components, or not. Solvent effect and reaction mechanism during the thermal cracking are also derived from the change of their chemical structures. Athabasca tar sand bitumen was separated into light and heavy fractions by vacuum distillation based on D-1660 of ASTM. Mixtures of the both fractions at various ratios were used as samples. Negative effect of the light fraction on cracking of the heavy fraction was observed with dealkylation and paraffin formation Polymerization of the dealkylated light fraction to the heavy fraction was suggested due to lack of ...
The refrigerant two-phase flows in a distributor and a simulated plate heat exchanger with a single passage used in a compression-type refrigerator were visualized by real-time neutron radiography. For a distributor, the liquid fraction in the each tube was measured by some image processing method. On the other hand, for a plate heat exchanger, the two-dimensional distribution of void fraction was measured quantitatively by the umbra method. As a result, it was shown that the dynamic behaviors of refrigerant at the inlet of the section strongly affected on the performance, that is, a distribution performance of a distributor and a liquid distribution in a plate heat exchanger. (author)
A few industry-derived and conventional building materials have above acceptable radioactivity. An examination of some materials presently used, or with a potential for use, has shown that in phosphogypsum, fly ash, zircon kyanite tailings, red mud and brickmaking clay, the radium equivalent activities of the finer fractions (<53 #mu#) are higher than those of the larger fractions. Consequently, the radioactivity of these materials could be reduced by dry-sieving and discarding the fines. In blast furnace slag and dissociated zircon, no such reduction would occur since the radioactivity is evenly distributed in all sized fractions.
Particle Swarm Optimization technique offers optimal or suboptimal solution to multidimensional rough objective functions. In this paper, this optimization technique is used for designing fractional order PID controllers that give better performance than their integer order counterparts. Controller synthesis is based on required peak overshoot and rise time specifications. The characteristic equation is minimized to obtain an optimum set of controller parameters. Results show that this design method can effectively tune the parameters of the fractional order controller.
A real-time two-dimensional void fraction distribution measurement of gas-liquid two-phase flow was carried out by real-time neutron radiography and real-time image processing. The JRR-3M real-time thermal neutron radiography system and a Musashi dynamic image processing system were used. Image processing methods to calculate two-dimensional and cross-sectional void fraction distributions were proposed. The void fraction distribution was calculated by non-linear processing of the neutron radiography image and displayed by pseudo-color in real-time. A simple gas-liquid two-phase flow induced by injecting gas through needles at the bottom of water pool in a rectangular vessel was tested. (orig.).
The Proportional-Integral-Derivative Controller is widely used in industries for process control applications. Fractional-order PID controllers are known to outperform their integer-order counterparts. In this paper, we propose a new technique of fractional-order PID controller synthesis based on peak overshoot and rise-time specifications. Our approach is to construct an objective function, the optimization of which yields a possible solution to the design problem. This objective function is optimized using two popular bio-inspired stochastic search algorithms, namely Particle Swarm Optimization and Differential Evolution. With the help of a suitable example, the superiority of the designed fractional-order PID controller to an integer-order PID controller is affirmed and a comparative study of the efficacy of the two above algorithms in solving the optimization problem is also presented.
The first space photographs were obtained from V-2 rockets fired upwards from the ..... Some fraction of the incoming solar radiation is reflected towards a sensor ...
Pore Fraction in Yttrium-Barium-Copper-Oxide and. Other Polycrystalline. Materials ...... Properties of Yttrium Ceramic. Sov. J. LowTemp.Phys. 14:395-402 . ...
A high pressure piezometer is described with which pVT-measurements on solutions of gases in liquids like oils can be performed at pressures and temperatures up to 2000 bar and 440 K, respectively. The present investigations deal mainly with the system squalaneCO/sub 2/ at different mole fractions, but also with squalaneN/sub 2/. The high accuracy of the measurements reveals a pronounced structure of the pV-curves in dependence on temperature and mole fraction. At larger mole fractions is the unequivocal assignment of the phases ambiguous, and the representation of the experimental data in terms of an equation of state not possible for the whole pressure and temperature range. However, for solutions with lower mole fractions could be determined the saturation pressures and the isothermal compressibility in the unsaturated region. Furthermore, the molar excess volumes of the mixture have been calculated ...
A process and apparatus for the production of coke, asphalt and jet fuel m a feed of fossil fuels containing volatile carbon compounds therein is disclosed. The process includes the steps of pyrolyzing the feed in an entrained bed pyrolyzing means, separating the volatile pyrolysis products from the solid pyrolysis products removing at least one coke from the solid pyrolysis products, fractionating the volatile pyrolysis products to produce an overhead stream and a bottom stream which is useful as asphalt for road pavement, condensing the overhead stream to produce a condensed liquid fraction and a noncondensable, gaseous fraction, and removing water from the condensed liquid fraction to produce a jet fuel-containing product. The disclosed apparatus is useful for practicing the foregoing process. the process provides a useful method of mass producing and jet fuels from materials such as coal, oil shale ...
We study dipolar bosons in a 1D optical lattice and identify a region in parameter space---strong coupling but relatively weak on-site repulsion---hosting a series of stable CDW states whose low-energy excitations, built from "fractional domain walls", are remarkably similar to those of non-abelian fractional quantum Hall states. Here, a conventional domain wall between translated CDW's may split by inserting strings of degenerate, but inequivalent, CDW states. Outside these insulating regions, we find numerous supersolids as well as a superfluid regime. The mentioned phases should be accessible experimentally, and in particular, the fractional domain walls can be created in the ground state using single-site addressing, i.e. by locally changing the chemical potential.
PurposeTo determine the dosimetric impact of inter-fraction anatomical movements in prostate cancer patients receiving proton therapy.Full Text Available
Diffusion in the extracellular space (ECS) of the brain is constrained by the volume fraction and the tortuosity and a modified diffusion equation represents the transport behavior of many molecules...Full Text Available
Background:To determine nutrient requirements by the carbon oxidation techniques, it is necessary to know the fraction of carbon dioxide produced during the oxidative...Full Text Available
Determination of the radiocarbon (14C) content of airborne particulate matter yields insight into the proportion of the carbonaceous material derived from fossil and contemporary carbon sources. Daily samples of PM2.5 were collected by high-volume sampler at an urban background site in Birmingham, UK, and the fraction of 14C in both the total carbon, and in the organic and elemental carbon fractions, determined by two-stage combustion to CO2, graphitisation and quantification by accelerator mass spectrometry. OC and EC content was also determined by Sunset Analyzer. The mean fraction contemporary TC in the PM2.5 samples was 0.50 (range 0.27-0.66, n=26). There was no seasonality to the data, but there was a positive trend between fraction contemporary TC and magnitude of SOC/TC ratio and fo...
The concentration of apolipoproteins was measured by quantitative immunoelectrophoresis in rat serum, in the lipoprotein-free ultracentrifugal fraction (density greater than 1.21) of serum, and in renal...Full Text Available
The challenges of lung cancer radiotherapy are intra/inter-fraction tumor/organ anatomy/motion changes and the need to spare surrounding critical structures. Evolving radiotherapy technologies, such...Full Text Available
Radio-frequency catheter ablation (RFCA) of the distal pulmonary veins is increasingly being used to treat recurrent or refractory atrial fibrillation that doesn't respond to pharmacologic therapy or cardioversion. Successful RFCA of atrial al fibrillation depends on the pre-procedural understanding of the complex anatomy of the distal pulmonary veins and the left atrium. Aim of this parer is to describe the technical main features that characterise the multidetector helical computed tomography in the evaluation of this anatomic region before and after RFCA procedure. The 3D post-processing techniques useful for pre-RFCA planning are straightforward.
We report results of measurements and analysis of the heat capacity of MnSi. The measurements included data collection at a magnetic field of 4T, which suppresses strongly the longitudinal spin fluctuations and the phase transition. To analyze the experimental data, calculations of the phonon spectrum and phonon density of states in MnSi were performed. Inelastic neutron scattering with a polycrystalline sample of MnSi was used to validate the computational results. The combination of the experimental and theoretical data turned out to be decisive in revealing some hidden features of the thermal excitations in MnSi. In particular, the analysis of the available data led conclusively to the existence of a negative contribution to the heat capacity and entropy in MnSi at T>Tc, implying that a specific spin ordering process did occur in the paramagnet phase of MnSi.
The authors search Z{prime} bosons in dielectron events produced in p{bar p} collisions at {radical}s = 1.96 TeV, using a 0.45 fb{sup -1} dataset accumulated with the CDF II detector at the Fermilab Tevatron. To identify the Z{prime} {yields} e{sup +}e{sup -} signal, both the dielectron invariant mass distribution and the angular distribution of the electron pair are used. No evidence of a signal is found, and 95% confidence level lower limits are set on the Z{prime} mass for several models. Limits are also placed on the mass and gauge coupling of a generic Z{prime}, as well as on the contact interaction mass scales for different helicity structure scenarios.
We present the effects of heavy CP-even (H) and CP-odd (A) Higgs bosons on the production cross section of the process {gamma}{gamma}{yields}tt at the energy around the mass poles of the Higgs bosons. It is found that interference between H and A with small mass gap, as well as the ones between Higgs bosons and continuum, contributes to the cross section, if the photon beams are polarized and if we observe the helicity of the top quarks. It is demonstrated in the framework of the minimal supersymmetric extension of the standard model that the H and A contributions can be sizable at future {gamma}{gamma} colliders for small values of tan {beta}. The methods to measure the CP-parity of the Higgs boson are also presented. The statistical significance of detecting the Higgs signals and measuring the Higgs CP-parity is evaluated. (orig.)
We present the effects of heavy CP-even (H) and CP-odd (A) Higgs bosons on the production cross section of the process #gamma##gamma##->#tt at the energy around the mass poles of the Higgs bosons. It is found that interference between H and A with small mass gap, as well as the ones between Higgs bosons and continuum, contributes to the cross section, if the photon beams are polarized and if we observe the helicity of the top quarks. It is demonstrated in the framework of the minimal supersymmetric extension of the standard model that the H and A contributions can be sizable at future #gamma##gamma# colliders for small values of tan #beta#. The methods to measure the CP-parity of the Higgs boson are also presented. The statistical significance of detecting the Higgs signals and measuring the Higgs CP-parity is evaluated. (orig.)
The positive-energy unitary irreducible representations of the q-deformed conformal algebra #delta#C_q = U_q(su(2,2)) are obtained by appropriate deformation of the classical ones. When the deformation parameter q is N -th root of unity, all these unitary representations become finite-dimensional. For his case we discuss in some detail the massless representations, which are also irreducible representations of the q-deformed Poincare subalgebra of #delta#C_q. Generically, their dimensions are smaller than the corresponding finite-dimensional non-unitary representation of su(2,2), except when N = 2 modul h + 1, where h is the helicity of the representations. The latter cases include the fundamental representations with h = #+-#1/2. (author). 10 refs.
We have observed EUV spectra from the Large Helical Device (LHD) at the National Institute for Fusion Science (NIFS). We measured spectra of impurity ions; carbon, iron, xenon, tin and tungsten ions. In some cases, the plasma evolution was stable and a steady discharge was obtained, but sometimes the plasma underwent radiation collapse and rapid cooling. For carbon and iron spectra, we studied plasma diagnostics by intensity ratios of spectral lines. For other spectra of higher Z element, xenon, tin and tungsten, we studied mainly on line identifications comparing with theoretical calculations and experimental data. Related atomic data for these researches will be also discussed. (author)
We show that the recently measured asymmetry in helicity-angle spectra of the #LAMBDA#-hyperons, produced in the reaction pp#->#K"+#LAMBDA#p reaction, and the energy dependence of the total pp#->#K"+#LAMBDA#p cross-section can be explained consistently by the same #LAMBDA#p final-state interaction. Assuming that there is no final-state interaction in the #SIGMA#"0 p channel, as suggested by the available data for the reaction pp#->#K"+#SIGMA#"0p, we can also reproduce the energy dependence of the #LAMBDA#/#SIGMA#"0 production ratio and, in particular, the rather large ratio observed near the reaction thresholds. The nominal ratio of the #LAMBDA# and #SIGMA#"0 production amplitudes squared, i.e. when disregarding the final-state interaction, turns out to be about 3, which is in line with hyperon production data from proton and nuclear targets available at high energies. (orig.)
Electrostatic separation has already proved to be an effective means for the recycling of granular plastics from industrial wastes. The aim of the present work was to optimize the operation of a novel device that could ensure effective triboelectric charging of such materials prior to their selective sorting in a high-intensity electric field. The experiments were performed on two sorts of mm-size granular materials Acrylonitrile Butadiene Styrene and High Impact Polystyrene, originating from the processing of waste electric and electronic equipment. The samples were introduced in a Polyvinyl Chloride cylinder, where a co-axial propeller entrained the plastic granules into a helical motion that favored their triboelectric charging by combining the mechanical and aerodynamical effects. The ...
Since the elucidation of the structure of double helical DNA, the construction of small molecules that recognize and react at specific DNA sites has been an area of considerable interest. In particular, the study of transition metal complexes that bind DNA with specificity has been a burgeoning field. This growth has been due in large part to the useful properties of metal complexes, which possess a wide array of photophysical properties and allow for the modular assembly of an ensemble of recognition elements. Here we review recent experiments in our laboratory aimed at the design and study of octahedral metal complexes that bind DNA non-covalently and target reactions to specific sites. Emphasis is placed both on the variety of methods employed to confer site-specificity and upon the many applications for these complexes. Particular attention is given to the family of complexes recently designed that target single base mismatches in duplex DNA through ...
Since the elucidation of the structure of double helical DNA, the construction of small molecules that recognize and react at specific DNA sites has been an area of considerable interest. In particular, the study of transition metal complexes that bind DNA with specificity has been a burgeoning field. This growth has been due in large part to the useful properties of metal complexes, which possess a wide array of photophysical attributes and allow for the modular assembly of an ensemble of recognition elements. Here we review recent experiments in our laboratory aimed at the design and study of octahedral metal complexes that bind DNA non-covalently and target reactions to specific sites. Emphasis is placed both on the variety of methods employed to confer site-specificity and upon the many applications for these complexes. Particular attention is given to the family of complexes recently designed that target single base mismatches in duplex DNA through ...
We present a systematic study of the magnetization, Hall effect and specific heat on single crystals of Mn{sub 4}Si{sub 7}. Curie-Weiss law is observed above 43 K. At low-temperature moments order in an anisotropic helical state and are aligned above 1 T. We observe an anomalous Hall effect in both {rho}{sub H} vs. B and in R{sub H} vs. T curves and a field dependence of the low T specific heat due to spin fluctuations. The magnetic moments (p{sub eff} and p{sub sat}) are the lowest reported for similar itinerant magnetic systems, this suggests that Mn{sub 4}Si{sub 7} is a good candidate to observe critical quantum fluctuations expected for a marginal Fermi liquid.
A comparative study on the interaction of (PEG-co-P(FA/SC)-co-PEG) triblock copolymer with bovine and human insulins was carried out using isothermal titration calorimetry (ITC), circular dichroism (CD), and fluorescence spectroscopy. ITC data show that the copolymer has a low affinity for both proteins, with an association constant of about 7?9?103?M ?1. Results also show that binding is enthalpically driven, and disfavored by conformational entropy. CD spectroscopy studies reveal a small increase in the helical content and a decrease in ?-structure as well as random coil in both proteins. Acrylamide quenching experiments display reduced accessibility of tyrosines, while intrinsic fluorescence spectra show lower tyrosine emission. Furthermore, thermal unfolding experiments, studied by far...
SMART (System-Integrated Modular Advanced Reactor) is a first-of-the-kind integral reactor with 330 MW thermal power under active development by Korea Atomic Energy Research Institute (KAERI) for power generation and seawater desalination. SMART employs various design features that are not typically found in other nuclear power plants. Examples include a unique passive residual heat removal system (PRHRS), and enclosure of a pressurizer, eight helical steam generators, and eight canned reactor coolant pumps inside the reactor pressure vessel. This paper presents risk insights on the SMART reactor gained during the development of a regulatory PSA model by Korea Institute of Nuclear Safety (KINS)
This Letter reports the first experimental results from the world's first distributed optical-klystron (DOK) free-electron laser (FEL), the DOK-1 FEL, at Duke University. The DOK-1 FEL is a hybrid system, comprised of four wigglers: two horizontal and two helical. With the DOK-1 FEL, we have obtained the highest FEL gain among all storage ring based FELs at 47.8% (#+-#2.7%) per pass. We have also demonstrated that the FEL gain can be enhanced by increasing electron bunching using wigglers with a different polarization. Furthermore, we have realized controlled polarization switches of the FEL beam by a nonoptical means through the manipulation of a buncher magnet.
It is shown that a gun similar to that in the SSPX could demonstrate the high fields required for Pulsed Spheromak reactors merely by prolonging the pulse. Important considerations are choosing the voltage to exceed ohmic losses; designing the gun to avoid wasteful short-circuiting of current within the gun; and the injection efficiency factor, f, determined by the ''sag'' in the profile of {lambda} = {mu}{sub o}j/B. Typically f = 0.75 in experiments, giving an overall efficiency > 50 % if short-circuiting is avoided. Theoretical transport models agree qualitatively with the need for a finite gradient in h to pump in helicity by current-driven tearing modes and suggest that pressure-driven resistive modes would not compete with current-driven modes during a buildup to ohmic ignition.
Initial ICRF heating experiment in the LHD was carried out in 1998. One pair of the movable loop antennas was used and the coupling resistance was around one ohm for the low density ECH plasma. The loading characteristics were consistent with the fast wave excitation. By applying the ICRF heating of 300 kW to the ECH target plasma, the diamagnetic energy was increased from 13 kJ to 26 kJ. The heating performance was decided by hydrogen mixture rate on puffing gas. Efficient electron heating was observed at the higher hydrogen gas ratio. These results can be explained by the one dimensional wave analysis calculation on slab plasma model. (J.P.N.)
The effect of weak dissipation on drift orbits has been investigated making use of a simple mapping model in a helical magnetic field. It is found that, after many mapping iterations, any orbit tends to an attractor forming a vortex line even with very small dissipation. The convergence is faster for larger dissipation, i.e., the number of iteration N to converge within a certain distance from the attractor is inversely proportional to the amount of the dissipation. Although the behavior of orbits completely change, the basic stability characteristics of the system does not change, i.e, the coordinate of the attractors are determined by the stable fixed points in the area preserving system because the dissipation is very small. Since wide range of orbits are concentrated around the attractors after many toroidal circulations, a pinch effect is created by a small dissipation. Application of this pinch effect to fusion plasmas is discussed. (author)
Improved separation of heavier material from a dispersoid of gas and heavier material entrained therein is taught by the method of this invention which advantageously uses apparatus embodied in an inertial separator having rotary partition means comprising wall members dividing a housing into a plurality of axially-extending through passages arranged in parallel. Simultaneously with the helical transit of a moving stream of the dispersoid through the parallel arrangement of axially-extending through passages at a constant angular velocity, the heavier material is driven radially to the collecting surfaces of the rotational wall members where it is collected while the wall members are rotating at the same angular velocity as the moving stream. The plurality of wall members not only provides an increased area of collecting surfaces but the positioning of each of the wall members according to the teaching of this invention also results in a shortened time-of-flight to ...
Unitarity cuts are widely used in analytic computation of loop amplitudes in gauge theories such as QCD. We expand upon the technique introduced in hep-ph/0503132 to carry out any finite unitarity cut integral. This technique naturally separates the contributions of bubble, triangle and box integrals in one-loop amplitudes and is not constrained to any particular helicity configurations. Loop momentum integration is reduced to a sequence of algebraic operations. We discuss the extraction of the residues at higher-order poles. Additionally, we offer concise algebraic formulas for expressing coefficients of three-mass triangle integrals. As an application, we compute all remaining coefficients of bubble and triangle integrals for nonsupersymmetric six-gluon amplitudes.
The high temperature abrasive wear resistant of the composites with different Al{sub 2}O{sub 3} volume fractions, particle coating and size were investigated and the failure action of composites under different conditions at high temperature was analyzed. The results showed that the high temperature abrasive wear resistant of composite with Ni coating and wide size and 39% volume fraction of particle is the best among all composites examined. (orig.)
The results of the investigations show that magnetic treatment is a quite practical and effective method of intensifying certain technological processes in the coking industry. Magnetic treatment was utilized for improving the production of ammonium sulfate, refining of the naphthalene fraction, removal of sludge from wash oil in the benzol division, and the treatment of tar before fractionation. 2 references, 3 tables.
If 4-day-old dark-grown zucchini squash seedlings (Cucurbita pepo L. cv. Black Beauty) are exposed briefly to red light, subsequent cell fractionation yields about 40% of the total...Full Text Available
Using data collected with the BESII detector at $e^{+}e^{-}$ storage ring Beijing Electron Positron Collider, the measurements of relative branching fractions for seven Cabibbo suppressed hadronic weak decays $D^0 \\to K^- K^+$, $\\pi^+ \\pi^-$, $K^- K^+ \\pi^+ \\pi^-$ and $\\pi^+ \\pi^+ \\pi^- \\pi^-$, $D^+ \\to \\bar{K^0} K^+$, $K^- K^+ \\pi^+$ and $\\pi^- \\pi^+ \\pi^+$ are presented.
Nearly all chemical processes fractionate17O and 18O in a mass-dependent way relative to 16O, a major exception being the formation of ozone from diatomic oxygen in...Full Text Available
For the determination of the elemental composition of insoluble endogenous fractions from gastrointestinal tract by SRXRF (XRF experimental beam line, VEPP-3, INP SU RAS, Novosibirsk), an analytical method was developed for producing epithelial tissue in vivo. The metrological characteristics were determined using a number of international biological standards.
In normal subjects, apolipoprotein E (apo E) is present on very low density lipoproteins (VLDL) (fraction I) and on particles of a size intermediate between VLDL and low density lipoproteins (LDL) (fraction...Full Text Available
A design concept is presented for an in-bundle gamma densitometer system for measurement of subchannel average fluid density and void fraction in rod or tube bundles. This report describes (1) the application of the design concept to the Thermal-Hydraulic Test Facility (THTF) electrically heated rod bundle; and (2) results from tests conducted in the THTF.
Four solutions of the Cauchy problem for Mathieu?s equation away from parametric resonance domains are analytically constructed using an asymptotic averaging method in the fourth approximation. Three solutions occur near fractional parameter values at which slow combination phases exist. The fourth solution occurs in the absence of slow phases away from parametric resonance domains and the fractional parameter values.
A Real-Time Neutron Radiography (RTNR) system and a high speed X-ray Computed Tomography (X-CT) system are used to determine the flow regime, the instantaneous cross-sectional averaged void fraction, and the time averaged void fraction in a vertical annulus flow channel. A standard optical video system is also used to observe the flow regime. The annulus flow channel is operated as a bubble column and measurements are obtained for gas flow rates form 0.0 to 30.0 l/min. The flow regimes observed by all three measurement systems via image analysis shows that the results agree well with each other. Both the RTNR and the X-CT systems show that the time averaged and cross-sectional averaged void fraction increases with increasing superficial gas velocity. Time and cross-sectional averaged void fractions determined by the RTNR system agree within 4% with those determined by the high speed X-ray CT technique. ...
A Real-Time Neutron Radiography (RTNR) system and a high speed X-ray Computed Tomography (X-CT) system are used to determine the flow regime, the instantaneous cross-sectional averaged void fraction, and the time averaged void fraction in a vertical annulus flow channel. A standard optical video system is also used to observe the flow regime. The annulus flow channel is operated as a bubble column and measurements are obtained for gas flow rates form 0.0 to 30.0 l/min. The flow regimes observed by all three measurement systems via image analysis shows that the results agree well with each other. Both the RTNR and the X-CT systems show that the time averaged and cross-sectional averaged void fraction increases with increasing superficial gas velocity. Time and cross-sectional averaged void fractions determined by the RTNR system agree within 4% with those determined by the high speed X-ray CT technique. ...
Two experiments were conducted to evaluate the effect of compost addition to soil on fractionation and bioavailability of Cu, Mn, and Zn to four crops. Soils growing Swiss chard (Beta vulgaris var. cicla L.) and basil (Ocimum basilicum L.) were amended (by volume) with 0, 20, 40, and 60% Source-Separated Municipal Solid Waste (SS-MSW) compost, and dill (Anethum graveolens L.) and peppermint (Mentha X piperita L.) were amended with 0, 20, 40, and 60% of high-Cu manure compost (by volume). The SS-MSW compost applications increased the concentration of Cu and Zn in all fractions, increased Mn in acid extractable (ACID), iron and manganese oxides (FeMnOX), and organic matter (OM) fractions, but decreased slightly exchangeable-Mn. Addition of 60% high-Cu manure compost to the soil increased Cu EXCH, ACID, FeMnOX, and OM fractions, but decreased EXCH-Mn, and did not change EXCH-Zn. Addition of both composts ...
The relative roles of glomerular filtration, tubular reabsorption and tubular secretion in lead handling were evaluated using renal clearance technique, stop-flow analysis, and renal lead accumulation. In addition, the effect of altering acid-base status on renal handling of Pb was determined. Clearance of ultrafilterable lead was measured in anesthetized dogs during infusion of "2"0"3Pb with small doses of carrier Pb(0.5 to 50 #mu#g/kg/h). Filterable lead concentration was estimated by in vitro ultrafiltration of non-anticoagulated plasma. Fractional excretion of Pb was calculated using creatinine clearance to estimate glomerular filtration rate. Dogs in acute metabolic acidosis had the lowest fractional excretion of ultrafilterable Pb (< 0.1); those in alkalosis had high fractional Pb excretion (0.75 to 2.5) while normal dogs were intermediate (0.1 to .4). The fractional excretion of Pb during ...
A Real-Time Neutron Radiography (RTNR) system is used to determine two-phase flow parameters for a horizontal co-current two-phase flow channel with a CANDU-type 37 rod bundle. Image processing techniques are applied to visualize the two-phase flow, and to determine flow regime, cross-sectional averaged void fraction, time averaged void fraction, and void distribution. The experimentally determined flow regime map disagrees with existing flow regime models developed for the CANDU-type rod bundles. A new flow regime is observed and designated Large Amplitude Stratified Wavy flow. The results show that the LASW flow regime may be due to a combination of undeveloped flow phenomena, boundary conditions, and circumferential cross flow occurring in the bundle. The rods in the bundle may act as a dampener to the vertical flow and hinders the development of the wave into plug or slug flow by changing the momentum of the fluid in the circumferential ...
A real-time neutron radiography (RTNR) system is used to determine two-phase flow parameters for a horizontal co-current two-phase flow channel with a cylindrical 37 rod bundle. Image processing techniques are applied to visualize the two-phase flow, and to determine flow regime, cross-sectional averaged void fraction, time averaged void fraction, and void distribution. The experimentally determined flow regime map disagrees with existing flow regime models developed for the cylindrical rod bundles. A new flow regime is observed and designated large amplitude stratified wavy (LASW) flow. The results show that the LASW flow regime may be due to a combination of undeveloped flow phenomena, boundary conditions, and circumferential cross flow occuring in the bundle. The rods in the bundle may act as a dampener to the vertical flow component and hinders the development of the wave into plug or slug flow by changing the momentum of the fluid in the ...
A Real-Time Neutron Radiography (RTNR) system is used to determine two-phase flow parameters for a horizontal co-current two-phase flow channel with a CANDU-type 37 rod bundle. Image processing techniques are applied to visualize the two-phase flow, and to determine flow regime, cross-sectional averaged void fraction, time averaged void fraction, and void distribution. The experimentally determined flow regime map disagrees with existing flow regime models developed for the CANDU-type rod bundles. A new flow regime is observed and designated Large Amplitude Stratified Wavy flow. The results show that the LASW flow regime may be due to a combination of undeveloped flow phenomena, boundary conditions, and circumferential cross flow occurring in the bundle. The rods in the bundle may act as a dampener to the vertical flow and hinders the development of the wave into plug or slug flow by changing the momentum of the fluid in the circumferential ...
In searching modulators of immunity and hematopoiesis among natural products, being used as foods, six herbs exhibited lymphocyte proliferation in vitro, and six exhibited augmentation of hematopoietic cell growth. The combined treatments showed synergistic effects of lymphocyte proliferation and of hematopoietic cell growth. On the other hand, we found four effective oriental medicinal prescriptions, used as energy tonic or blood-building decoctions, for survival and regeneration of hematopoietic cells and for protection of stem cells of intestinal crypt in irradiated mice. On the basis of these results, extracts from combinations of herbs were made in expectation of higher effects in the three respects. In immuno modulation activity by the two combinations of herbs was confirmed in mice. In culture of bone narrow cells, growth improvement of non-adherent precursor and induction of cytokine expression by herb mixture extracts were observed. In evaluation of ...
A Real-Time Neutron Radiography (RTNR) system and a high speed X-ray Computed tomography (X-CT) system are compared for measurement of two-phase flow. Each system is used to determine the flow regime, and the void fraction distribution in a vertical annulus flow channel. A standard optical video system is also used to observe the flow regime. The annulus flow channel is operated as a bubble column and measurements obtained for gas flow rates from 0.0 to 30.01/min. The flow regimes observed by all three measurement systems through image analysis shows that the two-dimensional void fraction distribution can be obtained. The X-CT system is shown to have a superior temporal resolution capable of resolving the void fraction distribution in an (r,{theta}) plane in 33.0 ms. Void fraction distribution for bubbly flow and slug flow is determined.
A Real-Time Neutron Radiography (RTNR) system and a high speed X-ray Computed tomography (X-CT) system are compared for measurement of two-phase flow. Each system is used to determine the flow regime, and the void fraction distribution in a vertical annulus flow channel. A standard optical video system is also used to observe the flow regime. The annulus flow channel is operated as a bubble column and measurements obtained for gas flow rates from 0.0 to 30.01/min. The flow regimes observed by all three measurement systems through image analysis shows that the two-dimensional void fraction distribution can be obtained. The X-CT system is shown to have a superior temporal resolution capable of resolving the void fraction distribution in an (r,#theta#) plane in 33.0 ms. Void fraction distribution for bubbly flow and slug flow is determined.
A stable isotope mass-balance of dissolved inorganic carbon during a blue-green algae bloom in a softwater lake demonstrates that at low partial pressure of carbon dioxide there must be a large net negative carbon isotope fractionation between atmospheric CO/sub 2/ and the CO/sub 2/ absorbed by lake water at pH = 9.5. Chemical enhancement of CO/sub 2/ invasion at high pH by the reaction CO/sub 2/ + OH/sup -/ ..-->.. HCO/sub 3//sup -/ at large apparent film thicknesses may result in carbon isotope fractionation approaching that for a hydroxide solution. This phenomenon, coupled with a decrease in the photosynthetic fractionation, forced the surface water of a softwater lake to achieve increasingly negative delta /sup 13/C values during an algal bloom, which is in the opposite sense to the trend that results from photosynthesis under less extreme conditions. This and other similar systems must operate under non-equilibrium ...
The usefulness of helical CT early phase images optimized by the SmartPrep method for evaluation of wall invasion by colorectal cancer was investigated. Between August 1997 and September 1998, CT was performed to evaluate the primary tumor and local extension in 10 consecutive patients with colorectal cancer confirmed by barium enema- and/or colonoscopy. Early-phase images were acquired by using SmartPrep application software. This method allows the optimal scan delay time to be obtained by continuous monitoring of increases in CT values after injection of contrast medium. Sections of the surgical specimens, close to the same plane as the CT images, and of the same slice thickness, were analyzed histopathologically. All 10 cancers, regardless of size, showed strong enhancement on the early-phase images (81.4-112 HU, mean: 95.1 HU). The strongly enhanced image areas on CT corresponded to the primary cancer areas on histopathological specimens. A low-density zone was ...
The purpose of this study was to evaluate time management and workflow for multidetector-row helical CT (MDCT). Time for patient and data handling of at total of 580 patients were evaluated at two different time periods (December 1999, August 2000), each for the following baseline measurements: (a) change of clothes/instruction; (b) patient placement on the CT table/i.v. catheter; (c) CT planning and programming; (d) CT data acquisition; (e) CT data reconstruction; (f) CT data storage/printing. All imaging was performed on a Somatom Volume Zoom (Siemens, Erlangen, Germany). Time measurements summarized for different CT protocols revealed the following: (a) 5:01 min (#+-#2.06 min); (b) 4:36 min (#+-#2.43 min); (c) 4:11 min (#+-#2.55 min); (d) 0:43 min (#+-#0.15 min); (e) 6:59 min (#+-#2.39 min); (f) 09:51 min (#+-#3.51 min). Planning and programming was most time-consuming for CT angiography, whereas chest and abdominal CT needed only 3:26 and 3:30 min, ...
Active contrast material extravasation can be recognized with conventional CT scanners, though it has been considered a rare finding. Helical CT seems to increase the detection rate and especially to boost the radiologist's confidence in this diagnosis. Though active bleeding is defined in severely-injured subjects requiring urgent intervention and may be associated with findings of hypovolaemic shock, it should not be considered itself as a negative prognostic factor. Contrast extravasation is due to ongoing hemorrhage and its detection is critical for urged treatment. Accurate anatomical location permits to choose surgical management or transcatheter embolization and thus decreases time consumption for precis e bleeding site identification. [Italian] Lo stravaso attivo del mdc e' rilevabile anche con appropriate apparecchiature TC tradizionali, sebbene sia stato considerato raro. La TC sprirale sembra aumentare la frequanza del riconoscimento e ...
The purpose of this study is to investigate the feasibility of visualization and void fraction measurement of air-water two-phase flow in a small diameter tube (I.D.: 4.08 mm) by using the real-time neutron radiography and image processing techniques. Video images of two-phase flow were taken by using the real-time neutron radiography system (thermal neutron radiography facility No.2) installed at the Japan Research Reactor 3M of the Japan Atomic Energy Research Institute. The shape of bubbles and its moving behavior were clearly observed from the video images. The image corrections for dark current, shading, field intensity fluctuation and electrical system drift were examined in order to measure the void fraction from the video images. Though, generally speaking, the effect of the scattered neutron could not be ignored for quantification of the images taken by the neutron radiography, the scattered neutron could not affect the final results ...
The purpose of this study is to investigate the feasibility of visualization and void fraction measurement of air-water two-phase flow in a small diameter tube (inner diameter; 4.08mm) by using the real-time neutron radiography and image processing techniques. Video images of two-phase flow were taken by using the real-time neutron radiography system (thermal neutron radiography facility No.2) installed at the Japan Research Reactor 3 M of the Japan Atomic Energy Research Institute. The shape of bubbles and its moving behavior were clearly observed from the video images. The image corrections for dark current, shading, field intensity fluctuation and electrical system drift were examined in order to measure the void fraction from the video images. Though, generally speaking, the effect of the scattered neutron could not be ignored for quantification of the images taken by the neutron radiography, the scattered neutron could not affect the final ...
The purpose of this study is to investigate the feasibility of visualization and void fraction measurement of air-water two-phase flow in a small diameter tube (I.D.: 4.08 mm) by using the real-time neutron radiography and image processing techniques. Video images of two-phase flow were taken by using the real-time neutron radiography system (thermal neutron radiography facility No.2) installed at the Japan Research Reactor 3M of the Japan Atomic Energy Research Institute. The shape of bubbles and its moving behavior were clearly observed from the video images. The image corrections for dark current, shading, field intensity fluctuation and electrical system drift were examined in order to measure the void fraction from the video images. Though, generally speaking, the effect of the scattered neutron could not be ignored for quantification of the images taken by the neutron radiography, the scattered neutron could not affect the final results ...
Real-time neutron radiography has been used to study the dynamic behavior of two-phase flow and measure vapor fractions in a steam-water duct at atmospheric pressure. This unique experimental technique offers one the opportunity to observe and record on videotape now Patterns and transient behavior of two-phase flow inside opaque containers without perturbing the environment. The neutron radiographic technique is non-intrusive and requires no special transparent window region. Data are recorded simultaneously over a large area of interest. Image processing of the video data can be employed to measure bubble velocities and time-averaged and Instantaneous vapor fractions.
This paper describes a series of tests investigating two-phase flow regimes in a transparent model of a PWR hot leg. Test conditions were selected to cover a wide range of gas and liquid superficial velocities (.01 m/s 2 m/s) were also performed for comparison with semi-analytical predictions. Results include average void fractions, flow rates, and visual characterizations of the two-phase flow phenomena. Results show generally good agreement with Taitel and Duckler flow regime map and Zuber-Findlay correlation for average void fraction in vertical pipes. Results also indicate that flow regimes and collapsed liquid level (void fraction) are more strongly dependent on air flow rate (air superficial velocity) than water flow rate (water superficial velocity).
Molar excess volumes have been determined by means of a vibrating-tube densimeter for binary liquid mixtures of cycloalkanones (cyclopentanone and cyclohexanone) + cyclohexane, + benzene, and + tetrachloromethane. The V/sup E/ data are reported over the complete mole fraction range at 288.15, 298.15, and 308.15{Kappa}. The obtained excess volumes are positive for mixtures of cyclopentanone with cyclohexane and are negative for mixtures of the cycloalkanones with benzene and tetrachloromethane; for the system cyclohexanone-cyclohexane the V/sup E/ values are positive for a wide range of mole fraction, but at very low cyclohexane mole fraction an inversion of the sign of V/sup E/ is observed. The data show that in the considered range of temperature the values of the temperature coefficient ({partial derivative}V/sup E//{partial derivative}T) are negative for mixtures of the cycloalkanones with benzene and are almost zero for ...
The state of prooxidant-antioxidant homeostasis in Guinea pigs exposed to whole-body fractionated X-irradiation (5 fractions of 0.2 Gy at a 24 hr interval, up to total dose of 1.0 Gy, at a dose rate of 0.425 R/min) and a possibility of its disturbance correction with the complex of vitamins C, E and P was studied. Accumulation of primary and secondary lipid peroxidation products, decrease of the ascorbic acid content, increase of the content of its oxidized forms (dehydroascorbic acid and diketogulonic acid) in radiosensitive and radioresistant organs were found. Antioxidant complex administration reduced the disturbances of prooxidant-antioxidant homeostasis, but did not provide complete normalization.
Simple, one-zone models for inhomogeneous chemical evolution of the Galactic halo are used to predict the number fraction of zero-metallicity, Population III stars, which currently is empirically estimated at < 4e-4. These analytic models minimize the number of free parameters, highlighting the most fundamental constraints on halo evolution. There are disagreements of at least an order of magnitude between observations and predictions in limiting cases for both homogeneous Simple Model and Simple Inhomogeneous Model (SIM). Hence, this demonstrates a quantitative, unambiguous discrepancy in the observed and expected fraction of Population III stars. We explore how the metallicity distribution of the parent enrichment events f(z_0) drives the SIM and predictions for the Population III fraction. The SIM shows that the previously-identified "high halo" and "low halo" populations are consistent with a continuous evolutionary ...
Two rapidly solidified powders with compositions Al-6.7 wt.% Fe-5.9 wt.% Ce and Al-6.2 wt.% Fe-5.9 wt.% Ce-1.63 wt.% Si were separated into -32 [mu]m and +32 to -63 [mu]m size fractions. Powders from both size fractions were extruded at 500 C. For comparison purposes, extrusion at a lower temperature of 400 C was also performed. In this investigation, tensile property evaluation indicated that processing of finer size fractions at high temperature offers no advantages in terms of the tensile properties but is advantageous in terms of improving the fracture toughness of alloy B. These observations underline the importance of the stability of powder microstructure during thermomechanical processing for the development of optimum mechanical properties. (orig.)
The environmental behavior of antibiotics has attracted great research attention. However, their sorption mechanisms in soils/sediments are still unknown. Comparison of the sorption properties between the widely-studied hydrophobic organic contaminants (HOCs) and antibiotics may provide valuable insight to antibiotic sorption mechanisms. Thus, in this study batch experiments for pyrene (PYR), bisphenol A (BPA), and sulfamethoxazole (SMX) sorption were conducted on a sediment sample and its separated fractions. Our results showed the high sorption of PYR on black carbon and organic matter. Although high sorption of SMX was observed for both separated organic fractions (humic acids) and inorganic mineral particles, the original sediment particles showed relatively low sorption. Competitive s...
Depending on the soil environment, selenium (Se) can exist as several species differing greatly in bioavailability. Characterization of soil Se reserves is thus necessary in assessing the nutritional supply of this essential element. In low-Se areas, Se fertilization is an option for securing adequate Se nutrition. Fertilization is, however, challenged by the unknown fate of the residual Se. In this study, we aimed to clarify the Se status of selenate-fertilized field soils by fractionating soil Se into five pools: salt-soluble (KCl), adsorbed (KH2PO4/K2HPO4), organically associated (NaOH), elemental (Na2SO3) and recalcitrant Se (NaOCl). Changes induced in these fractions by repeated application of low selenate doses were examined by comparing samples collected from the same locations in 1...
All measurements were made with the NBS high-pressure photoionization mass spectrometer. The fractional of C/sub 5/H/sub 10//sup +/ions in a cyclopentane-cyclohexane mixture were determined as a function of pressure in order to define the fraction of the ions which did charge exchange with cyclohexane; i.e. the fraction which remained cyclic after ionization. The data for mixtures of various compositions (2.5 to 10% cyclohexane) are summarized for measurements performed at 10.62 eV: (a) 292K, > 96% cyclic; 347 K, greater than or equal to 94% cyclic; 386 K, 84 +- 4% cyclic; and 412 K, 78 +- 6% cyclic; entropy, enthalpy, and activation energy were determined; 10.49 eV was obtained as the ionization potential of cyclopentane. 1 figure.
Protein kinase C activity has been identified in the rat brown adipocyte. About 60% of this activity is found in the cytosolic fraction under basal conditions, and 12-O-tetradecanoylphorbol 13-acetate (TPA) causes a rapid shift from the cytosol to the particulate fraction. Norepinephrine and phenylephrine causes a similar redistribution that can be blocked by prazosin but not by alprenolol. {alpha}{sub 1}-Adrenergic agonists cause three- to fivefold stimulation of type 2 iodothyronine 5{prime}-deiodinase activity in brown adipocytes. TPA has no effect on basal deiodinase activity and reduces the response of the enzyme to {alpha}{sub 1}-adrenergic agonists. These results suggest that the translocation of protein kinase C from cytosol to particulate fraction is not sufficient to increase deiodinase activity but can modulate the {alpha}{sub 1}-adrenergic agonist-mediated responses in these cells.
The factors influencing premixed burning and the importance of premixed burning on the exhaust emissions from a small high-speed direct-injection diesel engine were investigated. The characteristics of premixed and diffusion burning were examined using a single-zone heat-release analysis. The mass of fuel burned in premixed combustion was found to be linearly related to the product of engine speed and ignition-delay time and to be essentially independent of the total amount of fuel injected. Accordingly, the premixed-burned fraction increased with increasing engine speed, with decreasing fuel-air ratio and with retarding injection timing. The hydrocarbon emissions did not correlate well with the premixed-burned fraction. In contrast, the oxides of nitrogen emissions were found to increase with decreasing premixed-burned fraction, indicating that diffusion burning, and not premixed burning, is the primary source of oxides of ...
On the basis of a numerical model, the temperature and liquid fraction of spray-formed H13 tool steel are calculated as a function of time. Results show that a preheated substrate at the appropriate temperature can lead to very low porosity by increasing the liquid fraction in the deposited steel. The calculated cooling rate can lead to a microstructure consisting of martensite, lower bainite, retained austenite, and proeutectoid carbides in as-spray-formed material. In the temperature range between the solidus and liquidus temperatures, the calculated temperature of the spray-formed material increases with increasing substrate preheat temperature, resulting in a very low porosity by increasing the liquid fraction of the deposited steel. In the temperature region where austenite decomposit...
Fractionation of isotopes of the alkali metals and the alkaline earth metals in ion exchange chromatography of their chlorides was studied. The heavier isotopes of potassium and rubidium were found to be preferentially fractionated into the ion exchanger phase while the lighter isotopes of lithium, magnesium, calcium and strontium were enriched in the exchanger phase. This can be interpreted as a resultant of the relative significance of isotope effect upon dehydration and isotope effect accompanying the phase change of the hydrated metal ion. Found was no evidence of anomalous isotope effect attributable to the odd-even difference in mass number of isotopes. Based on the spectroscopic and solution chemical data (experimental and theoretical), the isotopic reduced partition function ratios of the hydrated alkaline metal ions and stretching force constants of metal ion-hydrating water bonds were estimated. (author).
The effects of five extraction solvents and their mixtures on the yield of metabolites in crude and fractionated extracts of Annona muricata L. leaves were investigated by direct comparison. Extraction media were prepared using simplex centroid mixtures of ethanol, ethyl acetate, dichloromethane, acetone, and chloroform. The effects of the mobile phase solvent strength and the analysis wavelength on the chromatographic separation were also investigated. Solvent mixtures rather than pure solvents were found to be the most efficient extractors for the different fractions. The results indicated that the mobile phase composed of methanol/acetonitrile/water (26:27:47 v/v/v) was most suitable for the basic fraction analysis at 254 nm, whereas the mobile phase composed of methanol/acetonitrile/wa...
Neutron radiography systems are being used for real-time visualization of the dynamic behavior as well as time-averaged measurements of spatial vapor fraction distributions for two phase fluids. The data in the form of video images are typically recorded on videotape at 30 frames per second. Image analysis of he video pictures is used to extract time-dependent or time-averaged data. The determination of the average vapor fraction requires averaging of the logarithm of time-dependent intensity measurements of the neutron beam (gray scale distribution of the image) that passes through the fluid. This could be significantly different than averaging the intensity of the transmitted beam and then taking the logarithm of that term. This difference is termed the dynamic error (error in the time-averaged vapor fractions due to the inherent time-dependence of the measured data) and is separate from the static error (statistical ...
In the past shredder fluff from automobile recycling was discarded in landfills, but shrinking landfill space and the partly hazardous content of the fluff as well as its caloric value, all resulted in efforts to turn this waste problem into an energy resource. In order to produce a fuel, the inorganic compounds have to be removed. Extensive analyses and particle size measurements were made on fluff from various shredder. For optimal separation all particles are reduced to a uniform, relatively small size. In a subsequent combined screening and air classification process, successful separation into organic and inorganic fractions is achieved. The inorganic fraction is treated in a heavy media or an eddy-current separator to recover the valuable metals, while the organic fraction is now suitable for thermal processing, such as fluidized bed gasification and using the resulting carbon as a chemical reagent.
An estimate for the number of ionizing photons per baryon as a function of redshift is computed based on the plausible extrapolation of the observed galaxy UV luminosity function and the latest results on the properties of the escape fraction of ionizing radiation. It is found that, if the escape fraction for low mass galaxies (Mtot<10^{11}Msun) is assumed to be negligibly small, as indicated by numerical simulations, then there are not enough ionizing photons to reionize the universe by z=6 for the cosmology favored by the WMAP 3rd year results, while the WMAP 1st year cosmology is marginally consistent with the reionization requirement. The escape fraction as a function of galaxy mass would have to be constant to within a factor of two for the whole mass range of galaxies for reionization to be possible within the WMAP 3rd year cosmology.
This study investigated the optimum polyphenol extraction conditions for two Nigerian green leafy vegetables, Vernonia amygdalina (VA) and Gongronema latifolium (GL) that are widely used for food and medicinal purposes. Seven different solvents were used to extract the total phenolic contents of the leaves; 100% acetone, 80% acetone, 50% acetone, 100% ethanol, 70% ethanol, 100% methanol and 70% methanol and their total phenolic contents were determined. The results showed that the 80% acetone was significantly (p<0.05) the most effective for polyphenol extraction from the leaves and generally the acetone-containing solvents were more effective than alcohol-containing solvents. The 80% acetone extract was fractionated on a silicic acid-packed column to give two main fractions: acetone elute...
We have recently introduced several important improvements in the measurement of distillation curves for complex fluids. The modifications include a composition-explicit data channel for each distillate fraction (for both qualitative and quantitative analysis) and corrosivity assessment of each distillate fraction. The composition-explicit information is achieved with a new sampling approach that allows precise qualitative as well as quantitative analyses of each fraction, on the fly. We have applied the new method to a variety of fluids, including simple n-alkanes, rocket propellant, gasoline, jet fuels, and a hydrocarbon fluid made corrosive with dissolved hydrogen sulfide. In the current contribution, we present the application of the advanced distillation curve method to two samples of...
We have recently introduced several important improvements in the measurement of distillation curves for complex fluids. This new method is a significant improvement over current approaches, with features including a composition-explicit data channel for each distillate fraction (for both qualitative and quantitative analysis), trace chemical analysis of each distillate fraction, and a corrosivity assessment of each distillate fraction. In the present contribution, we present the application of the advanced distillation curve method to a bio-derived crude oil prepared from swine manure. One motivation behind the work was to precisely measure the distillation curve of the oil derived from swine manure with our advanced distillation apparatus and compare the bio-derived oil to traditional pe...
A Real-Time Neutron Radiography (RTNR) system is developed to determine two-phase flow parameters for a vertical co-current two-phase flow channel with a hexagonal finned bundle. Image processing techniques are applied to visualize the two-phase flow, and procedures for measuring flow regime, cross-sectional averaged void fraction, time averaged void fraction, and void distribution for this complex geometry are discussed. The results show that the experimental flow regime map agrees well with an existing flow regime model for a hexagonal fined bundle. The hexagonal finned bundle is observed to significantly affect the void fraction, void migration, and void fluctuation along the axial flow channel.
A sensitive and rapid method to evaluate toxic and genotoxic properties of drinking water supplied from Lake Trasimeno (Umbria, Central Italy) was worked out analysing bile in Cyprinus carpio exposed for 20d to lake water treated with 3 different disinfectants, sodium hypochlorite (NaClO), chlorine dioxide (ClO2) and peracetic acid (PAA). Fish were sacrificed at 0, 10 and 20d in order to investigate the time course of these endpoints. An aliquot of bile samples was fractionated by adsorption on C18 silica cartridges and the genotoxic potential of whole bile and of bile fractions was evaluated by the single-cell microgel-electrophoresis (comet) assay on human colonic adenocarcinoma cells (Caco-2). Bile (both whole and fractionated) from specimens exposed to the three disinfectants always sh...
System identification refers to estimation of process parameters and is a necessity in control theory. Physical systems usually have varying parameters. For such processes, accurate identification is particularly important. Online identification schemes are also needed for designing adaptive controllers. Real processes are usually of fractional order as opposed to the ideal integral order models. In this paper, we propose a simple and elegant scheme of estimating the parameters for such a fractional order process. A population of process models is generated and updated by particle swarm optimization (PSO) technique, the fitness function being the sum of squared deviations from the actual set of observations. Results show that the proposed scheme offers a high degree of accuracy even when the observations are corrupted to a significant degree. Additional schemes to improve the accuracy still further are also proposed and analyzed.
Statistical design of experiments is widely used among scientists and engineers to understand influential factors in a laboratory or manufacturing process. One of the underlying principles of...Full Text Available
An interfacial shear stress equation in the dispersed-annular two-phase flow regime has been developed, which is based on a three-fluid model consisting of a liquid film on a rod, vapor and entrained liquid associated with a vapor flow. It is an extension of J.G.M. Andersen's procedure that provides a two-fluid interfacial shear stress equation using the drift flux parameters C{sub 0} and V{sub gj}. This interfacial shear stress equation can take into account a phase and velocity distribution through an equivalence between the drift flux parameters and the interfacial shear stress. Using the three-fluid subchannel analysis code TEMPO with the three-fluid interfacial shear stress model the capability of a three-fluid calculation using the drift flux parameters C{sub 0} and V{sub gj} that reproduce a measured void fraction is demonstrated. A comparison was made with advanced X-ray computed tomography (CT) void fraction data within a 4x4 ...
This research aims at elucidating thermal hydraulic phenomena by carrying out their visualization and measurement which are difficult by conventional method, utilizing the excellent properties of real time neutron radiography and showing the usefulness of neutron radiography. The experiments were carried out on the visualization and measurement of liquid metal flow and mixed phase flow and the visualization and diagnosis of mixed phase flow equipment. As the achievement in this fiscal year, the image-processing method for visualizing quantitatively the distribution of void fraction in gas-liquid two-phase flow has been devised, therefore, its method and results are reported. For the analysis of multi-dimensional two-phase flow, in order to prepare the model and determine the constitution equation, the data on the multi-dimensional distribution of void fraction are required. Void fraction is defined. The method of image ...
Subcellular-fractionation techniques were used to characterize the endocytic pathway followed by ricin in rat liver in vivo and tentatively identify the site(s) at which the ricin interchain disulphide...Full Text Available
Particle swarm optimization (PSO) is extensively used for real parameter optimization in diverse fields of study. This paper describes an application of PSO to the problem of designing a fractional-order proportional-integral-derivative (FOPID) controller whose parameters comprise proportionality constant, integral constant, derivative constant, integral order (lambda) and derivative order (delta). The presence of five optimizable parameters makes the task of designing a FOPID controller more challenging than conventional PID controller design. Our design method focuses on minimizing the Integral Time Absolute Error (ITAE) criterion. The digital realization of the deigned system utilizes the Tustin operator-based continued fraction expansion scheme. We carry out a simulation that illustrates the effectiveness of the proposed approach especially for realizing fractional-order plants. This paper also attempts to study the ...
We study the redshift evolution of galaxy pair fractions and merger rates for different types of galaxies using kinematic pairs selected from the DEEP2 Redshift Survey. Parameterizing the evolution of the pair fraction as (1+z)^{m}, we find that the companion rate increases mildly with redshift with m = 0.41+-0.20 for all galaxies with -21 < M_B^{e} < -19. Blue galaxies show slightly faster evolution in the blue companion rate with m = 1.27+-0.35 while red galaxies have had fewer red companions in the past as evidenced by the negative slope m = -0.92+-0.59. We find that at low redshift the pair fraction within the red sequence exceeds that of the blue cloud, indicating a higher merger probability among red galaxies compared to that among the blue galaxies. With further assumptions on the merger time scale and the fraction of pairs that will merge, the galaxy major merger rates for 0.1 < z ...
Norepinephrine stimulates the growth of a range of bacterial species in nutritionally poor SAPI minimal salts medium containing 30% serum. Addition of size-fractionated serum components to SAPI...Full Text Available
BackgroundCaesarean section is one of the most commonly performed operations on women throughout the world. Rates have increased in recent years – about 20–25% in...Full Text Available
BackgroundMicrovascular injury plays a key role in normal tissue radiation responses. Statins, in addition to their lipid-lowering effects, have vasculoprotective...Full Text Available
The separation of bitumens (B) and natural asphalts using a dialysis (D) method is studied. A moderately vulcanized latex of natural rubber, which was subjected to extraction by cold n-hexane prior to use, was used as the material of the membrane for dialysis. With dialysis of bitumen samples dispersed in a small quantity of n-alkane in a Soxhlet apparatus three fractions were acquired: a dialyzate, an undialyzable fraction and asphaltenes (the residue). N-pentane, n-hexane and n-heptane were used as the solvents for dialysis. Samples of oxidized road bitumen, grade AOSI 85/25, bitumens from the process of propane deasphaltization, natural asphalts from Trinidad and Albania and A80 grade bitumens from the oil distillation process were isolated using the dialysis method. The reproducability of the output of the fractions with varying suspensions and productivity of the dialysis, the dependence of the output on the length of ...
Proteins in the ALA-D (delta-aminolaevulinic acid dehydratase) fraction from gel filtration of erythrocyte supernatant (ES) have the highest affinity for lead among erythrocyte constituents in vivo...Full Text Available
OBJECTIVE: To evaluate prospectively the efficacy of a single fraction of high-dose radiotherapy in patients with Kaposi's sarcoma. PATIENTS: Between 1994 and 2004, 47 patients with Kaposi's sarcoma...Full Text Available
Two xyloglucan fractions have been isolated from the cotyledons of resting white-mustard seeds, the first by extraction with hot EDTA, and the second by subsequent extraction with alkali or lithium...Full Text Available
The plasma protein binding of phenytoin was investigated in 100 epileptic patients, using equilibrium dialysis at 37 degrees C. The unbound fractions of phenytoin in plasma formed a skewed distribution,...Full Text Available
The purpose of the present work was to study the pharmacokinetics and the protein binding (free fraction of the drug) of ceftriaxone (CTX) during pregnancy. Nine pregnant women (ages, 20 to 34 years)...Full Text Available
An enriched glucan synthase fraction was obtained from red beet root microsomes by sequential extraction with the detergents 3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonate and digitonin....Full Text Available
Theoretical investigations on the phase change materials (PCMs) used as the heat storage media for box-type solar cookers have been conducted in this study. The selected PCMs are magnesium nitrate hexahydrate, stearic acid, acetamide, acetanilide and erythritol. For a two-dimensional simulation model based on the enthalpy approach, calculations have been made for the melt fraction with conduction only. Different materials such as glass, stainless steel, tin, aluminum mixed, aluminum and copper are used as the heat exchanger container materials in the numerical calculations. The large value of thermal conductivity of heat exchanger container material did not make a significant contribution on the melt fraction except for at very low thermal conductivities. Based on the theoretical results, stearic acid and acetamide are found to be good compatibility with latent heat storage system. It is also found that the initial temperature of PCM does not ...
Transposable elements (TEs) comprise a large fraction of mammalian genomes. A number of these elements are actively jumping in our genomes today. As a consequence, these insertions provide a source...Full Text Available
The fraction of a given area of ground that is covered by hail can be determined by using an airborne infrared thermometer. If the ambient ground temperature and the hail-covered ground temperature are measured with the same thermometer, and the surface o...
Despite the availability of dozens of animal genome sequences, two key questions remain unanswered: First, what fraction of any species' genome confers biological function, and second, are apparent...Full Text Available
Basal segments taken from Old Home and Bartlett pear hardwood cuttings collected at intervals during the rooting period in September were extracted with ethanol and fractionated by paper chromatography...Full Text Available
BackgroundA large fraction of the human genome is attributable to L1 retrotransposon sequences. Not only do L1s themselves make up a significant portion of the genome, but L1-encoded...Full Text Available
The various steps of gas treatment in the Sasol II coal liquefaction plant are discussed: CO/sub 2/ removal, separation of the hydrocarbon fractions and the recirculated hydrogen by low-temperature decomposition, production of pure hydrogen by alternating pressure absorption.
The functional and thermodynamic characteristics of the ubiquinolcytochrome (Cyt) c oxidoreductase in a Cyt b/c1-enriched fraction (defined...Full Text Available
Background:There is a need for simple imaging parameters capable of predicting therapeutic outcome.Methods:This retrospective study analysed 50 patients...Full Text Available
In recent years, Salmonella enteritidis has become an increasingly important public health problem in Italy. In some parts of the country, the fraction of total human salmonella isolates...Full Text Available
The effect of organic (fulvic and humic acids) and inorganic fractions of soil on the sorption and extractability of /sup 239/Pu(IV) as a function of pH was determined by using an equilibrium batch technique. The results indicated that Pu(IV) is strongly sorbed on the inorganic fraction of the soil under soil pH conditions normally encountered in natural environments. Plutonium appeared to form stable complexes or chelates with fulvic and humic acids in the pH range studied (1.3 to 11.7). In mixtures of pure fulvic or humic acids with soil inorganic fractions, extractability of Pu was substantially influenced by organic-inorganic interaction. The influence of the inorganic fractions was most evident in the lower pH ranges, whereas that of the organic materials was most evident in the higher pH ranges, generally above pH 6. Some implications of the results on plutonium movement in soils were discussed.
High-density lipoproteins (HDL) were examined as potential carriers of small peptides in plasma. HDL purified by density gradient centrifugation was delipidated and fractionated by size-exclusion...Full Text Available
A new process for the hydrogenation of coal in the presence of wide-cut coal tar was proposed; it involves cavitation treatment, mixing with catalytic additives, and heating the resulting mixture at an elevated pressure in an atmosphere of hydrogen. The yields of hydrocarbon fractions to 300?C and gas condensate were evaluated.
Quantitative metallography is often used to confirm the proper processing of aerospace metallic materials. A microstructural feature of great importance for titanium alloys processed in the alpha-beta phase field is the volume fraction of primary alpha. S...
BackgroundEchocardiography is widely used in the management of patients with cardiogenic shock (CS). Left ventricular ejection fraction (EF) has been shown to be an independent predictor...Full Text Available
Feb 15, 2008 ... hydrological properties (e.g., hydrometeor budgets, cloud ice/water, transports ... cloud fraction, mass and particle size. In combination, these .... anomaly in the LS is not simply due isentropic movement of water vapor relative ...
The monoterpene fraction of the lemon-scented sweet basil (Ocimum basilicum) cv Sweet Dani consists mostly of citral (a mixture of geranial and neral), with lower levels of geraniol...Full Text Available
The German state of Sachsen is a synonym for brown coal production. The elections to the state parliament will decide the future of this echnology and of climate protection strategies like renewable energy sources. A renewables fraction of 82 percent of renewables-derived electric power may be possible by 2020. (orig.)
The report gives results of an examination, including mutagenic screening, of the chemical composition of residual fuel oils and their column chromatography pre-fractions. A degree of correlation between composition and mutagenicity has been achieved. Radionuclide data has been o...
Based on the assumption that an accelerated proliferation process prevails in tumour cell residues after surgery, the possibility that treatment acceleration would offer a therapeutic advantage in postoperative...Full Text Available
In the past decade in vitro tests have been developed that represent a range of anatomic structure from perfused whole organs to subcellular fractions. To assess the use of in vitro tests for toxicity...Full Text Available
The pattern of biodegradation and the chemical changes occurring in the macromolecular fraction of domestic sludge during autothermal thermophilic aerobic digestion (ATAD) was monitored and characterised...Full Text Available
Drell-Yan pair production is investigated. We reexamine a model where the quark momentum fraction is defined as the ratio of the corresponding light-cone components of the quark and parent nucleon in a naive parton-model approach. It is shown that the results differ from the standard parton model. This is due to unphysical solutions for the momentum fractions within the naive approach which are not present in the standard parton model. In a calculation employing full quark kinematics, i.e., including primordial quark transverse momentum, these solutions also appear. A prescription is given to handle these solutions in order to avoid incorrect results. The impact of these solutions in the full kinematical approach is demonstrated and compared to the modified result.
The processes psi'-->p pbar pi^0 and psi'-->p pbar eta are studied using a sample of 14 million psi' decays collected with the Beijing Spectrometer at the Beijing Electron-Positron Collider. The branching fraction of psi'-->p pbar pi^0 is measured with improved precision as (13.2\\pm 1.0\\pm 1.5)\\times 10^{-5}, and psi'-->p pbar eta is observed for the first time with a branching fraction of (5.8\\pm 1.1\\pm 0.7)\\times 10^{-5}, where the first errors are statistical and the second ones are systematic.
Multiphase flow calculation software and computer-readable media carrying computer executable instructions for calculating liquid and gas phase mass flow rates of high void fraction multiphase flows. The multiphase flow calculation software employs various given, or experimentally determined, parameters in conjunction with a plurality of pressure differentials of a multiphase flow, preferably supplied by a differential pressure flowmeter or the like, to determine liquid and gas phase mass flow rates of the high void fraction multiphase flows. Embodiments of the multiphase flow calculation software are suitable for use in a variety of applications, including real-time management and control of an object system.
Dietary supplements of about 5 g/kg of a number of amino acids increased tissue lead concentrations in newly weaned rats but decreased them in older rats. The retention of both oral and intraperitoneal lead was affected. The uptake of "2"0"3Pb by tissues was reduced when methionine was given in the diet over a period of 5 weeks or when it or ethionine was given by mouth 24 h before the activity was measured. In the liver the fraction of the total activity found in the nuclei and mitochondria was increased by methionine, but in the kidney only the fraction found in nuclei was increased.
Multi-dimensional modelling of two-phase flow requires accurate constitutive relationships for interfacial parameters such as interfacial heat transfer, void fraction distribution, interfacial area, etc. However, existing diagnostic systems for measurement of two-phase flow parameters have difficulty measuring two or three-dimensional void distributions required for determination of interfacial parameters. In this work, a Real-Time Neutron Radiography (RTNR) system is developed for non-intrusive measurement of two-phase flow parameters in nuclear fuel channels at low thermal neutron fluxes (on the order of 10{sup 6}n/cm{sup 2}-s). This advanced radiation technique has the advantage of measuring two-phase flow in 3 1/2 dimensions (x,{integral}dy,t) where the 1/2 dimension refers to an integrated or averaged space dimension. Pipe flow channels, annulus flow channels, MAPLE-type nuclear fuel flow channels, and CANDU-type nuclear fuel flow channels are investigated. ...
Multi-dimensional modelling of two-phase flow requires accurate constitutive relationships for interfacial parameters such as interfacial heat transfer, void fraction distribution, interfacial area, etc. However, existing diagnostic systems for measurement of two-phase flow parameters have difficulty measuring two or three-dimensional void distributions required for determination of interfacial parameters. In this work, a Real-Time Neutron Radiography (RTNR) system is developed for non-intrusive measurement of two-phase flow parameters in nuclear fuel channels at low thermal neutron fluxes (on the order of 10"6n/cm"2-s). This advanced radiation technique has the advantage of measuring two-phase flow in 3 1/2 dimensions (x,#integral#dy,t) where the 1/2 dimension refers to an integrated or averaged space dimension. Pipe flow channels, annulus flow channels, MAPLE-type nuclear fuel flow channels, and CANDU-type nuclear fuel flow channels are investigated. Measurements ...
A preliminary investigation was completed on the characterization and decontamination of coral samples from Johnston Island. These samples were found to contain individual particles (2 to 0.25 mm) of contaminated coral as well as a piece of contaminated magnetic metal. They ranged in activity from about 70 to 811 nCi Am-241. The decontamination methods investigated were froth flotation, ferrite treatment, attrition scrubbing, ultrasonic treatment and dry sieving. Dry sieving, the more effective technique, separated about 42 wt % of the coral into a decontaminated fraction. This fraction (>4 mm) contained about 0.5% of the total activity. 7 refs., 3 tabs.
The identification and characterization of carbonaceous materials (CMs) that control hydrophobic organic chemical (HOC) sorption is essential to predict the fate and transport of HOCs in soils and sediments. The objectives of this paper are to determine the types of CMs that control HOC sorption in the oxidized and reduced zones of a glacially deposited groundwater sediment in central Illinois, with a special emphasis on the roles of kerogen and black carbon. After collection, the sediments were treated to obtain fractions of the sediment samples enriched in different types of CMs (e.g., humic acid, kerogen, black carbon), and selected fractions were subject to quantitative petrographic analysis. The original sediments and their enrichment fractions were evaluated for their ability to sorb trichloroethene (TCE), a common groundwater pollutant. Isotherm results and mass fractions of CM enrichments were ...
Adjuvant-induced arthritis in rats is a chronic inflammatory disease, widely as an animal model for rheumatoid arthritis. In our study the effect of various fractions of dialyzable leukocyte extract (DLE): DLE I-molecular weight below 10 kDa (commercial preparation), DLE II-molecular weight below 5 kDa (suppressor fraction), DLE III-molecular weight 5-10 kDa on rat adjuvant-induced arthritis was studied. The adjuvant arthritic (AA) rats were treated with DLE fractions i.p. in solutions containing an active substance isolated from 12.5 x 10{sup 6} and 6.25 x 10{sup 6} leukocytes from day 1 (adjuvant injected) through day 18, every second day (total 9 times). Various markers in inflammation, immune function and joint destruction were evaluated: hind paw volume, serum hyaluronic acid, serum albumin and biopterin in urine. All these markers showed a significant improvement after using fraction DLE II in ...
Two-phase air-water flows in a microscale fractal-like flow network were experimentally studied and results were compared to predictions from existing macroscale void fraction correlations and flow regime maps. Void fraction was assessed using (1) two-dimensional analysis of high-speed images (direct method) and (2) experimentally determined using gas velocities (indirect method). Fixed downstream-to-upstream length and width ratios of 1.4 and 0.71, respectively, characterize the five-level flow network. Channels were fabricated in a 38 mm diameter silicon disk, 250 {mu}m deep disk with a terminal channel width of 100 {mu}m. A Pyrex top allowed for flow visualization. Superficial air and water velocities through the various branch levels were varied from 0.007 m/s to 1.8 m/s and from 0.05 m/s to 0.42 m/s, respectively. Two-phase flow regime maps were generated for each level of the flow network and are well predicted by the Taitel and Dukler ...
Two-phase air-water flows in a microscale fractal-like flow network were experimentally studied and results were compared to predictions from existing macroscale void fraction correlations and flow regime maps. Void fraction was assessed using (1) two-dimensional analysis of high-speed images (direct method) and (2) experimentally determined using gas velocities (indirect method). Fixed downstream-to-upstream length and width ratios of 1.4 and 0.71, respectively, characterize the five-level flow network. Channels were fabricated in a 38 mm diameter silicon disk, 250 ?m deep disk with a terminal channel width of 100 ?m. A Pyrex top allowed for flow visualization. Superficial air and water velocities through the various branch levels were varied from 0.007 m/s to 1.8 m/s and from 0.05 m/s to 0.42 m/s, respectively. Two-phase flow regime maps were generated for each level of the flow network and are well predicted by the Taitel and Dukler model. ...
The importance of cellular dosimetry in both diagnostic and therapeutic nuclear medicine is becoming increasingly recognized. Experimental range-energy relations for electrons and alpha particles, along with derived geometric reduction factors, are used to calculate cellular absorbed fractions for these radiations. The resulting absorbed fractions are employed to calculate cellular S-values for several radionuclides. Cellular absorbed fractions for monoenergetic electron sources with energies ranging from 0.1 keV to 1 MeV, distributed uniformly in the source region, are calculated for several target {l_arrow} source combinations including cell{l_arrow}cell, cell{l_arrow}cell surface, nucleus{l_arrow}nucleus, nucleus {l_arrow}cytoplasm and nucleus {l_arrow}cell surface. Similar data are also provided for monoenergetic alpha particle sources with energies ranging from 3 to 10 MeV. S-values are also conveniently tabulated for ...
Medicinal plants play a major role in the life of Turkish people and of late medicinal plant usage has increased in many countries. Green plants in general contain mutagenic and carcinogenic substances, but there is little information about the biological activities of herbal medicine. In the present study, therefore, various Turkish medicinal herbs were investigated for their genotoxic potential in the Salmonella typhimurium microsomal activation assay and the alkaline single cell gel electrophoresis (COMET) assay. Extracts from these medicinal herbs and some fractions of these extracts were examined. The species investigated were Arctium minus, Ecballium elatterium, Momordica charantia, Plantago major, Urtica dioica, Viscum album, Salvia triloba, Euphorbia rigida, Stachys lavandulifolia, Acteoside, Abies nordmannia. They are used for various immune disorders and are applied either topically or taken orally as a herbal tea. Of the 19 samples of the extracts and ...
Escherichia coli spheroplast protein y (EcSpy) is a small periplasmic protein that is homologous with CpxP, an inhibitor of the extracytoplasmic stress response. Stress conditions such as spheroplast formation induce the expression of Spy via the Cpx or the Bae two-component systems in E. coli, though the function of Spy is unknown. Here, we report the crystal structure of EcSpy, which reveals a long kinked hairpin-like structure of four ?-helices that form an antiparallel dimer. The dimer contains a curved oval shape with a highly positively charged concave surface that may function as a ligand binding site. Sequence analysis reveals that Spy is highly conserved over the Enterobacteriaceae family. Notably, three conserved regions that contain identical residues and two LTxxQ motifs are placed at the horizontal end of the dimer structure, stabilizing the overall fold. CpxP also contains the conserved sequence motifs and has a predicted secondary structure similar ...
In this issue it has been investigated the yield of Helical CT in the study of lung vessels, the incidence of the angiogram sign and its actual value. July 1997 to December 1998, were studied 30 cases of pulmonary collapse of different origin. It was found 15 cases of passive collapse (10 from pleural effusion, 2 from diaphragmatic compression, 2 from traumatic pneumothorax, and 1 from isthmic aortic aneurysm), 12 cases of obstructive collapse (9 from bronchogenic carcinoma, 1 from mucoid obstruction, 1 from ilar lymphadenopathy, and 1 from mediastinal cancer), 2 cases of adhesive collapse and 1 case of round atelectasis. All the examinations were performed with the Helical technique during nonionic iodinated contrast agent injection (bolus, 300-350 mg/mL); it was used an automatic injector set at 2-3 mL/s. It was studied the images for the angiogram sign, that is hyperdense bands, usually longer than 2 cm, through the collapsed lung, which ...
We have performed multicanonical Monte Carlo simulations of C-peptide of ribonuclease A. It is known by CD and NMR experiments that this peptide has high alpha-helix content in aqueous solution and that the side-chain charges of residues Glu-2$^-$ and His-12$^+$ play an important role in the stability of the alpha-helix. In order to confirm these experimental implications, we have used two analogues of the peptide with charged and neutral side chains of Glu-2 and His-12. Two dielectric functions, distance-dependent and constant, are considered to study the effects of solvent contributions. All the simulations were started from random initial conformations. Various thermodynamic quantities such as average helicity as a function of residue number and average distance between two side chains as a function of temperature are calculated. The results are found to be in accord with the implications of CD and NMR experiments. The lowest-energy conformation obtained has an ...
SMART (System integrated Modular Advanced ReacTor) , is under development at the Korea Atomic Energy Research Institute (KAERI). SMART is an integral type pressurized water reactor which contains a pressurizer, 4 reactor coolant pumps (RCPs), and 8 steam generator cassettes(S/Gs) in a single reactor vessel. This reactor has substantially enhanced its safety with an integral layout of its major components, 4 trains of safety injection system (SIS), and an adoption of 4 trains of passive residual heat removal system (PRHRS) instead of an active auxiliary feedwater system . The thermal power is 330 MWth. During the conceptual design stage, a preliminary PSA was performed. PSA results identified that a steam generator tube rupture (SGTR) is one of the most important initiating events which results in a high core damage frequency. Clear understanding of accident progression with various combinations of the safety systems helps to develop an event tree of SGTR accident in the Level 1 PSA. ...
A process and apparatus for solidifying radioactive waste liquid containing dissolved and/or suspended solids is disclosed. The process includes chemically treating for pH adjustement and precipitation of solids, concentrating solids with a thin-film evaporator to provide liquid concentrate containing about 50% solids, and drying the concentrate with heated mixing apparatus. The heated mixing apparatus includes a heated wall and working means for shearing dried concentrate from internal surfaces and subdividing dry concentrate into dry, powdery particles. The working means includes a rotor and helical means for positively advancing the concentrate and resulting dry particles from inlet to outlet of the mixing apparatus. The dry particles may also be encapsulated in a matrix material. Entrained particles in the vapor stream from the evaporator and mixer are removed in an integral particle separator and the vapor is subsequently condensed and may be recycled upstream ...
Electron cyclotron emission (ECE) can be used to determine the electron temperature profile in magnetized plasmas. The complex structure of the magnetic field configuration in the Large Helical Device (LHD), which has a large shear, complicates the analysis of the ECE spectrum. In a sheared magnetic field the propagation of X and O-mode polarization through the plasma are coupled, causing mode conversion and polarization rotation. Mode scrambling is also caused by wall reflections. In this report, this mode conversion in LHD is numerically analyzed. It was found that at low density mode conversion scrambles the ECE spectra. However, at higher density (n{sub eo} > 1.0{center_dot}10{sup 19} m{sup -3}) the polarization mode is found to rotate with the sheared magnetic field, yielding only a negligible mode conversion. Wall reflections are found to depolarize the ECE spectrum. Notwithstanding the LHD magnetic configuration, it is shown that temperature profiles ...
We show that the recently measured asymmetry in helicity-angle spectra of the {lambda}-hyperons, produced in the reaction pp{yields}K{sup +}{lambda}p reaction, and the energy dependence of the total pp{yields}K{sup +}{lambda}p cross-section can be explained consistently by the same {lambda}p final-state interaction. Assuming that there is no final-state interaction in the {sigma}{sup 0} p channel, as suggested by the available data for the reaction pp{yields}K{sup +}{sigma}{sup 0}p, we can also reproduce the energy dependence of the {lambda}/{sigma}{sup 0} production ratio and, in particular, the rather large ratio observed near the reaction thresholds. The nominal ratio of the {lambda} and {sigma}{sup 0} production amplitudes squared, i.e. when disregarding the final-state interaction, turns out to be about 3, which is in line with hyperon production data from proton and nuclear targets available at high energies. (orig.)
The cell's cytoskeleton, providing the cell with structure and shape, consists of a complex array of structural proteins, including microtubules, microfilaments and intermediate filaments. Intermediate filaments play a crucial role in mechanotransduction and in providing mechanical stability to cells, in particular under large deformation. By utilizing molecular simulation, here we report a nanomechanical analysis of vimentin intermediate filament dimers, the basic building blocks of intermediate filaments. We describe a detailed analysis of the mechanical properties and associated deformation mechanisms, and find that mechanical stretch induces a transition from alpha-helices to beta-sheets, a phenomenon known as alpha-beta transition. A comparison of the Young's modulus predicted from simulation with experimental measurements is provided, and good agreement is found. We present an analysis of structural changes during deformation, domain unfolding patterns, rate ...
We report a new measurement of the exclusive electroproduction reaction {gamma}*p{yields}{pi}{sup 0}p to explore the evolution from soft nonperturbative physics to hard processes via the Q{sup 2} dependence of the magnetic (M{sub 1+}), electric (E{sub 1+}), and scalar (S{sub 1+}) multipoles in the N{yields}{delta} transition. 9000 differential cross section data points cover W from threshold to 1.4 GeV/c{sup 2}, 4{pi} center-of-mass solid angle, and Q{sup 2} from 3 to 6 GeV{sup 2}/c{sup 2}, the highest yet achieved. It is found that the magnetic form factor G{sub M}* decreases with Q{sup 2} more steeply than the proton magnetic form factor, the ratio E{sub 1+}/M{sub 1+} is small and negative, indicating strong helicity nonconservation, and the ratio S{sub 1+}/M{sub 1+} is negative, while its magnitude increases with Q{sup 2}.
We have researched several new focused ion beam (FIB) micro-fabrication techniques that offer control of feature shape and the ability to accurately define features onto nonplanar substrates. These FIB-based processes are considered useful for prototyping, reverse engineering, and small-lot manufacturing. Ion beam-based techniques have been developed for defining features in miniature, nonplanar substrates. We demonstrate helices in cylindrical substrates having diameters from 100 {micro}m to 3 mm. Ion beam lathe processes sputter-define 10-{micro}m wide features in cylindrical substrates and tubes. For larger substrates, we combine focused ion beam milling with ultra-precision lathe turning techniques to accurately define 25-100 {micro}m features over many meters of path length. In several cases, we combine the feature defining capability of focused ion beam bombardment with additive techniques such as evaporation, sputter deposition and electroplating in order to ...
We performed density functional calculations to examine the effects of solvation, hydrogen bonding, backbone conformation, and the side chain on 15N chemical shielding in proteins. We used N-methylacetamide (NMA) and N-formyl-alanyl-X (with X being one of the 19 naturally occurring amino acids excluding proline) as model systems. In addition, calculations were performed for selected fragments from protein GB3. The conducting polarizable continuum model was employed to include the effect of solvent in the density functional calculations. Our calculations for NMA show that the augmentation of the polarizable continuum model with the explicit water molecules in the first solvation shell has a significant influence on isotropic 15N chemical shift but not as much on the chemical shift anisotropy. The difference in the isotropic chemical shift between the standard ?-sheet and ?-helical conformations ranges from 0.8 to 6.2 ppm depending on the residue type, with the mean ...
In this study, the adoptable essential technologies and reference design concept of the advanced reactor were developed and related basic experiments were performed. (1) Once-through Helical Steam Generator: a performance analysis computer code for heli-coiled steam generator was developed for thermal sizing of steam generator and determination of thermal-hydraulic parameters. (2) Self-pressurizing pressurizer : a performance analysis computer code for cold pressurizer was developed. (3) Control rod drive mechanism for fine control : type and function were surveyed. (4) CHF in passive PWR condition : development of the prediction model bundle CHF by introducing the correction factor from the data base. (5) Passive cooling concepts for concrete containment systems: development of the PCCS heat transfer coefficient. (6) Steam injector concepts: analysis and experiment were conducted. (7) Fluidic diode concepts : analysis and experiment were conducted. (8) Wet thermal ...
This semiannual report for the period October 1983-March 1984 summarizes activities in Sandia National Laboratories' continuing program of coal liquefaction research. The primary goals are to: explore novel catalytic concepts and materials for conversion of coal to liquid fuels; determine the effects of process variables on catalyst deactivation; determine the effects of coal structure and solvent properties on low temperature dissolution; study the kinetics and catalysis of hydrogen transfer reactions; develop an understanding of slurry gelling phenomena; and provide a technical assessment of coal liquefaction processes. During this period, work was performed on: the use of pyrene as a chemical probe of catalyst activity; analysis of catalysts from Wilsonville run 242 using ESCA; atmospheric pressure model compound activity testing of regenerated catalysts from Wilsonville run 242; base displacement experiments with a coal-indole complex; preliminary hydrogenation tests with ...
This quarterly report for the period April through June 1984 summarizes activities in Sandia National Laboratories' continuing program of coal liquefaction research. The primary goals are to: explore novel catalytic concepts and materials for conversion of coal to liquid fuels; determine the effects of process variables on catalyst deactivation; determine the effects of coal structure and solvent properties on low temperature dissolution; study the kinetics and catalysis of hydrogen transfer reactions; develop an understanding of slurry gelling phenomena; and provide a technical assessment of coal liquefaction processes. During this period, work was performed on: analysis of catalyst samples from Wilsonville Run 246; catalyst presulfiding; catalyst activity testing using pyrene as a chemical probe; catalyst deactivation using a high-pressure model compound test reactor; dissolution chemistry of Wyodak coal; slurry gelling utilizing the helical screw ...
Abstract Plant annexins represent a multigene family involved in cellular elongation and development. A cDNA encoding a novel annexin was isolated from a cotton (Gossypium hirsutum) fiber cDNA library and designated-GhAnx1. This gene encodes a 316 amino acid protein with a theoretical molecular mass of 36.06 kDa and a theoretical pI of 6.19. At the amino acid level, it shares high sequence similarity and has evolutionary relationships with annexins from higher plants. The purified recombinant protein expressed in-Escherichia coli-was used to investigate its physicochemical properties. Circular dichroism spectrum analyses showed a positive peak rising to the maximum at 196 nm and a broad negative band rounding 215 nm, suggesting that the GhAnx1 protein was prominently -helical. The fluoresc...
Burner for feeding a solid and a liquid or gaseous fuel to a kiln comprises a central supply pipe for liquid or gas surrounded concentrically by a first pipe providing an annular passage through which primary air is supplied. Concentrically surrounding that pipe is a second pipe providing an annular channel for supply of solid fuel in carrier air stream. The outlet end of the first concentric pipe is closed by a plate fixed mounted at the pipe end and providing multiple nozzles having their axes parallel to the burner axis. The surface of the plate facing the burning zone provides a divergence opening for the central pipe while the inner surface is formed with helical teeth. These are engaged by complementary teeth mounted on the end of the central pipe which is rotatable and biased by springs so that the teeth are in engagement. Rotation of the pipe causes relative axial motion of the teeth to create tangential slots for admission of primary air into the central ...
The E6 oncoproteins of high-risk human papillomaviruses provide important functions not only for malignant transformation but also in the productive viral life cycle. E6 proteins have been shown to bind to a number of cellular factors, but only a limited number of analyses have investigated the effects of these interactions on the viral life cycle. In this study, we investigated the consequences of HPV 31 E6 binding to E6TP1, a putative Rap1 GAP protein. HPV 16 E6 has been shown to bind as well as induce the rapid turnover of E6TP1, and similar effects were observed with HPV 31 E6. Mutation of amino acid 128 in HPV 31 E6 was found to abrogate the ability to bind and degrade E6TP1 but did not alter binding to another ?-helical domain protein, E6AP. When HPV 31 genomes containing mutations a...
No information on steam/water two-phase flow behavior in large diameter pipes (10 inch or larger) at elevated pressures is available in the open literature. However, there are many applications, in the nuclear, chemical and petroleum industries among others where two-phase flows in large diameter pipes at elevated pressures and temperatures are encountered routinely or under accident scenarios. Experimental data on steam-water two-phase flow in a large diameter (20 inch, 50.08 cm I.D.) vertical pipe at elevated pressures and temperatures (2.8 MPa/230 C--6.4 MPa/280 C) have been obtained. Void fraction, two-phase mass flux, phase and velocity distributions as well as pressure drop along the test pipe have been measured using the Ontario Hydro Technologies (OHT) Pump Test Loop. The void fraction distributions were found to be axially symmetric and nearly flat over a wide range of two-phase flow conditions. The two-phase flow regime could be ...
No information on steam/water two-phase flow behavior in large diameter pipes (10 inch or larger) at elevated pressures is available in the open literature. However, there are many applications, in the nuclear, chemical and petroleum industries among others where two-phase flows in large diameter pipes at elevated pressures and temperatures are encountered routinely or under accident scenarios. Experimental data on steam-water two-phase flow in a large diameter (20 inch, 50.08 cm I.D.) vertical pipe at elevated pressures and temperatures (2.8 MPa/230 C--6.4 MPa/280 C) have been obtained. Void fraction, two-phase mass flux, phase and velocity distributions as well as pressure drop along the test pipe have been measured using the Ontario Hydro Technologies (OHT) Pump Test Loop. The void fraction distributions were found to be axially symmetric and nearly flat over a wide range of two-phase flow conditions. The two-phase flow regime could be ...
Background and purpose: In order to investigate the feasibility, toxicity and antitumor efficacy of hyperfractionated radiation therapy, 37 adult patients with incompletely resected supratentorial low-grade glioma were entered into a phase II study. Materials and methods: The radiation therapy dose was 55 Gy in 50 fractions in 25 treatment days over 5 weeks to the tumor plus a 2-cm margin, with an additional 17.6 Gy given in 16 fractions in 8 treatment days over 1.5 weeks to the tumor plus a 1-cm margin, using 1.1 Gy b.i.d. fractionation with a 6 h interfraction interval. The total tumor dose was 72.6 Gy in 66 fractions in 33 treatment days over 6.5 weeks. Results: The median survival time (MST) for all 37 patients has not yet been attained, while 5- and 7-year survival rates were 75% and 69%, respectively. The median time to tumor progression (MTP) has also not yet been attained, while 5- and 7-year ...
We have recently introduced several important improvements in the measurement of distillation curves for complex fluids. The modifications include a composition-explicit data channel for each distillate fraction (for both qualitative and quantitative analysis) and corrosivity assessment of each distillate fraction. The composition-explicit information is achieved with a new sampling approach that allows precise qualitative as well as quantitative analyses of each fraction, on the fly. We have applied the new method to a variety of fluids, including simple n-alkanes, rocket propellant, gasoline, jet fuels, and a hydrocarbon fluid made corrosive with dissolved hydrogen sulfide. In the current contribution, we present the application of the advanced distillation curve method to two samples of crude oil. A primary motivation behind the work is to precisely measure the distillation curves of these oils using our advanced ...
Purpose. We have tested a procedure of focal injection of the contrast medium Lipiodol as a fiducial marker for image-guided boost of the tumor in bladder cancer radiotherapy (RT). In this study, we have evaluated the feasibility and the safety of the method as well as the inter- and intra-fraction shift of the bladder tumor. Materials and methods. Five patients with muscle invasive urinary bladder cancer were included in the study. Lipiodol was injected during flexible cystoscopy into the submucosa of the bladder wall at the periphery of the tumor or the post resection tumor-bed. Cone-beam CT (CBCT) scans were acquired daily throughout the course of RT. Results. Lipiodol demarcation of the bladder tumor was feasible and safe with only a minimum of side effects related to the procedure. The Lipiodol spots were visible on CT and CBCT scans for the duration of the RT course. More than half of all the treatment fractions required a geometric shift ...
The behavior and properties of associated bodies were studied through measurement of surface tension considering acetone-soluble fraction relatively light among various solvent extracts of coal. In experiment, the acetone-soluble fraction was extracted from the substances extracted from Upper Freeport coal as standard specimen using the mixed solvent of carbon disulfide (CS2) and N-methyl-2-pyrrolidinone (NMP), and it was dissolved into NMP after drying. Surface tension was measured by Wilhelmy method. The experimental results are as follows. Equilibrium surface tension is equal to the surface tension of pure solvent in a low concentration range of solution, and decreases with an increase in concentration approaching a fixed value at 0 in log concentration, nearly showing an S curve. Adsorption of species with non-polar aromatic ring of the acetone-soluble fraction on a solution surface probably decreases surface tension. ...
The number and type of stem cells in spleen and bone marrow of mice were determined after exposure to a single dose of 150 R on day 6, to a single dose of 500 R on day 6 or day 9 or to a fractionated dose of 150 R + 350 R on day 6 and 9. The stem cells were assayed on the basis of colony forming units (CFU) in spleen and of incorporation of iododeoxyuridine in spleen and bone marrow of lethally irradiated host mice. During the first month of life, the number of stem cells in non-irradiated mice increases markedly in bone marrow and slightly in spleen. Irradiation causes a long-lasting depression in stem cells, particularly in bone marrow and affecting preferentially erythropoietic precursor cells. Following a dose of only 150 R, the number of CFU in bone marrow is still below control levels 24 days later. An exposure to 500 R fractionated between day 6 and 9 has a markedly greater effect on stem cells in the spleen than the same dose given in a ...
Atrazine and phenanthrene (Phen) sorption by nonhydrolyzable carbon (NHC), black carbon (BC), humic acid (HA) and whole sediment and soil samples was examined. Atrazine sorption isotherms were nearly linear. The single-point organic carbon (OC)-normalized distribution coefficients (K_O_C) of atrazine for the isolated HA1, NHC1 and BC1 from sediment 1 (ST1) were 36, 550, and 1470 times greater than that of ST1, respectively, indicating the importance of sediment organic matter, particularly the condensed fractions (NHC and BC). Similar sorption capacity of atrazine and Phen by NHC but different isotherm nonlinearity indicated different sorption domains due to their different structure and hydrophobicity. The positive relationship between (O + N)/C ratios of NHC and atrazine log K_O_C at low concentration suggests H-bonding interactions. This study shows that sediment is probably a less effective sorbent for atrazine than Phen, implying that atrazine applied in ...
In this paper heavy metal pollution at an abandoned Italian pyrite mine has been investigated by comparing total concentrations and speciation of heavy metals (Fe, Cu, Mn, Zn, Pb and As) in a red mud sample and a river sediment. Acid digestions show that all the investigated heavy metals present larger concentrations in the sediment than in the tailing. A modified Tessier's procedure has been used to discriminate heavy metal bound to organic fraction from those originally present in the mineral sulphide matrix and to detect a possible trend of metal mobilisation from red mud to river sediment. Sequential extractions on bulk and size fractionated samples denote that sediment samples present larger percent concentrations of the investigated heavy metals in the first extractive steps (I-IV) especially in lower dimension size fractionated samples suggesting that heavy metals in the sediment are significantly bound by ...
In this paper heavy metal pollution at an abandoned Italian pyrite mine has been investigated by comparing total concentrations and speciation of heavy metals (Fe, Cu, Mn, Zn, Pb and As) in a red mud sample and a river sediment. Acid digestions show that all the investigated heavy metals present larger concentrations in the sediment than in the tailing. A modified Tessier's procedure has been used to discriminate heavy metal bound to organic fraction from those originally present in the mineral sulphide matrix and to detect a possible trend of metal mobilisation from red mud to river sediment. Sequential extractions on bulk and size fractionated samples denote that sediment samples present larger percent concentrations of the investigated heavy metals in the first extractive steps (I-IV) especially in lower dimension size fractionated samples suggesting that heavy metals in the sediment are significantly bound by ...
A stochastic linear fractional programming (SLFP) approach is developed for supporting sustainable municipal solid waste management under uncertainty. The SLFP method can solve ratio optimization problems associated with random information, where chance-constrained programming is integrated into a linear fractional programming framework. It has advantages in: (1) comparing objectives of two aspects, (2) reflecting system efficiency, (3) dealing with uncertainty expressed as probability distributions, and (4) providing optimal-ratio solutions under different system-reliability conditions. The method is applied to a case study of waste flow allocation within a municipal solid waste (MSW) management system. The obtained solutions are useful for identifying sustainable MSW management schemes with maximized system efficiency under various constraint-violation risks. The results indicate that SLFP can support in-depth analysis of the ...
The effect of adriamycin in combination with radiation on the skin reactions of mouse feet has been examined under a variety of experimental conditions including: (a) hyperthermic treatment of the foot immediately following adriamycin administration, with the former given either just before or just after x irradiation, and (b) fractionated treatments of drug and radiation in a variety of sequences over an 18-day period. In the case of the most severe hyperthermic treatment, no increased radiation reactions were observed in the presence of adriamycin. However, in the case of the less severe hyperthermic treatment a small but significant increase in skin reactions was observed. In the study of fractionated drug and radiation treatments, an enhancement of reaction in those animals receiving combined modality treatment over those receiving radiation alone was seen in those groups where the initiation of drug treatment succeeded the initiation of ...
Empirical birthrate estimates for pulsar binaries depend on the fraction of sky subtended by the pulsar beam: the pulsar beaming fraction. This fraction depends on both the pulsar's opening angle and the misalignment angle between its spin and magnetic axes. Previous estimates use the average value for only two pulsars, i.e. PSRs B1913+16 and B1534+12. We explore how birthrate predictions depend on assumptions about opening angle and alignment, using empirically-motivated distributions to define an effective beaming correction factor, f_{b,eff}. For most known pulsars, we expect f_{b,eff} to be less than 6. We also calculate f_{b,eff} for PSRs J0737-3039A and J1141-6545, applying the currently available constraints for their beam geometry. Our median posterior birthrate predictions for tight PSR-NS binaries, wide PSR-NS binaries, and tight PSR-WD binaries are 89/Myr, 0.84/Myr, and 34/Myr, respectively. For pulsars with spin ...
The effect of irradiation on the tensile properties of oil palm empty fruit bunch (OPEFB) fiber reinforced poly(vinyl chloride)/epoxidized natural rubber (PVC/ENR) blends were studied. The composites were prepared by mixing the fiber and the PVC/ENR blend using HAAKE Rheomixer at 150 deg. C. The composites were then irradiated by using a 3.0 MeV electron beam machine at doses ranging from 0 to 100 kGy in air and room temperature. The tensile strength, Young's modulus, elongation at break and gel fraction of the composites were measured. Comparative studies were also made by using poly(methyl acrylate) grafted OPEFB fiber in the similar blend system. An increase in tensile strength, Young's modulus and gel fraction, with a concurrent reduction in the elongation at break (Eb) of the PVC/ENR/OPEFB composites were observed upon electron beam irradiation. Studies revealed that grafting of the OPEFB fiber with methyl acrylate did ...
A new separation process of saturated fatty acids (lauric acid-myristic acid) using crystallization from an aqueous ethanol solution has been examined. There were two vessels in this separation process: an extraction vessel and a crystallization vessel. The fatty acids in the aqueous phase were first extracted from their organic phase (melt) in the extraction vessel. The fatty acids in the aqueous phase were continuously introduced to the crystallization vessel, and then the fatty acids were crystallized there. The crystals of the fatty acids were collected continuously above the aqueous phase in the crystallization vessel. In this process, the yield and the purity of the crystals over time were measured, and it was found that the purity of lauric acid increased unsteadily up to 0.98 mole fraction of lauric acid with an increase in the yield of the low yield range. The mole fraction of ethanol in the aqueous phase could be significant to ...
A dilute tungsten heavy alloy consisting of 50W-35Ni-15Fe (wt pct) was liquid phase sintered at 1,500 C for times ranging from 30 to 960 minutes. This alloy corresponds to a nominal solid content of 20 vol pct at the sintering temperature. Because of the excess liquid, the alloy densified easily and exhibited extensive liquid-solid separation due to the density difference between the phases. The solid content at the compact bottom ranged from 45 to 70 vol pct over position and time. The microstructure of the settled region was quantified for volume fraction of tungsten, grain size, connectivity, and settled solid angle of repose. These results provide a basis for extending the microstructural parameters to possible microgravity conditions. The grain growth rate constant varies with the inverse 2/3 power of the volume fraction of liquid, possibly reflecting combined coalescence and solution-reprecipitation processes. This ...
A dilute tungsten heavy alloy consisting of 50W-35Ni-15Fe (wt pct) was liquid phase sintered at 1,500 C for times ranging from 30 to 960 minutes. This alloy corresponds to a nominal solid content of 20 vol pct at the sintering temperature. Because of the excess liquid, the alloy densified easily and exhibited extensive liquid-solid separation due to the density difference between the phases. The solid content at the compact bottom ranged from 45 to 70 vol pct over position and time. The microstructure of the settled region was quantified for volume fraction of tungsten, grain size, connectivity, and settled solid angle of repose. These results provide a basis for extending the microstructural parameters to possible microgravity conditions. The grain growth rate constant varies with the inverse 2/3 power of the volume fraction of liquid, possibly reflecting combined coalescence and solution-reprecipitation processes. This ...
An axisymmetric unit cell model based on a regular array of second-phase particles arranged on a BCC lattice is used to study deformation mechanisms of ferrite-pearlite structural steels. Microstructural characteristics of the steels were parameterized by the pearlite volume fraction, the aspect ratio of the pearlite particles, and the neighboring factor, which represents the ratio of interparticle spacing in the longitudinal direction to that in the transverse direction. FE analyses were carried out to investigate the macroscopic and microscopic response of unit cells with morphological features based on idealizations of the microstructures of the actual steels. Tensile properties of each constituent phase were obtained experimentally and used in the analyses. As compared to traditional axisymmetric models, the BCC tell model appears to be able to capture more realistically the behavior of the materials, and it accurately estimates the tensile behavior of the ...
The traditional view that Ly-alpha emission and dust should be mutually exclusive has been questioned more and more often, notably the observations of Ly-alpha emission from ULIRGs seems to counter this view. In this paper we seek to address the reverse question: How large a fraction of Ly-alpha selected galaxies are ULIRGs? Using two samples of 24/25 Ly-alpha emitting galaxies at z = 0.3/2.3 we perform this test, also including results at z = 3.1, and find that whereas the ULIRG fraction at z = 3.1 is very small, it systematically increases towards lower redshifts. There is a hint that this evolution may be quite sudden and that it happens around a redshift of z ~ 2.5. Measuring the infrared luminosities of the Ly-alpha emitters, we find that they are in the normal to ULIRG range in the lower redshift sample, whereas the higher redshift galaxies all have luminosities in the ULIRG category. The Ly-alpha escape fractions for ...
The NiMo sulfide supported on Ketjen Black (KB) was more effective and yielded lighter oil products containing light fractions with their boiling point below 300{degree}C during the two stage liquefaction combining low temperature and high temperature hydrogenation the conventional NiMo/alumina catalyst and FeS2 catalyst. Although the NiMo/alumina yielded increased oil products during the two stage liquefaction, the lighter oil fractions did not increase and the heavier fractions increased mainly. This suggests that the hydrogenation of aromatic rings and successive cleavage of the rings are necessary for producing the light oil, which is derived from the sufficient hydrogenation of aromatic rings using catalysts. For the two stage reaction with NiMo/KB catalyst, it was considered that sufficient hydrogen was directly transferred to coal molecules at the first stage of the low temperature reaction, which promoted the ...
The publication is an economic evaluation of the Bureau of Mines electrolytic process for recovering lead from scrap lead-acid batteries. In this process, scrap batteries are crushed and separated into metal and sludge fractions. The metal fraction is cast as anodes and electro-refined. Lead in the sludge fraction is converted to lead carbonate by reaction with an ammonium carbonate-ammonium bisulfite solution. The lead carbonate is then dissolved in a fluosilicic acid electrolyte from which pure lead metal is electrowon. A cost estimate is presented for a plant capable of processing 10,000 scrap batteries per day. The fixed capital cost for the plant is estimated to be $14 million on a fourth quarter 1984 basis. Operating costs are estimated to be $0.15/lb Pb recovered. Assuming a lead selling price of $0.17/lb, the interest rate of return on investment after taxes is 11 pct. A lead selling price of about $0.21/lb is ...
In the development of the specific mathematical modeling for heavy and ultra heavy petroleum fractions in a molecular distiller is very important the definition of physical and chemical parameters as density and specific heat of the mixture, the enthalpy of vaporization, among others, since they are used in the energy balance. Information on these properties and their variation with temperature are found in the open literature for mixture with few components (simple mixtures). However, for multicomponent solutions consisting of complex mixtures such as oil and its heavy and ultraheavy fractions, available data are few, or are limited to low temperatures. The specific heat is an important property in the energy balance. This property can be measured by Differential Scanning Calorimetry (DSC), which gives results with great sensitivity and accuracy. This paper presents the variation of specific heat with the temperature of ultra-heavy oil ...
The authors describe a cloning strategy for the construction of a human genomic library in yeast artificial chromosomes (YACs) based on complete digestion of high-molecular-weight DNA with the infrequently cutting restriction enzyme MluI. Cloning of MluI fragments in the vector pYAC-RC and one subsequent size fractionation by preparative pulsed-field gel electrophoresis yielded a library with average insert sizes of 600 kb. Ninety-seven percent of the colonies were recombinant. An additional size fractionation of MluI fragments prior to ligation had no significant influence on the size of the YACs. The library currently consists of 5000 clones, which is the equivalent of one human genome. Nineteen percent of the YACs were larger than 1.2 Mb. Since smaller MluI fragments are lost during sizing, they also performed cloning without size fractionation. Only 20% of the colonies were recombinant, probably due to unligated vector ...
Chandra and XMM surveys show that the fraction of obscured AGN decreases rapidly with increasing luminosity. Although this is usually explained by assuming that the covering factor of the central engine is much smaller at luminous QSOs, the exact origin of this effect remains unknown. We perform toy simulations to test whether photo-ionisation of the obscuring screen in the presence of a strong radiation field can reproduce this effect. In particular, we create X-ray spectral simulations using a warm absorber model assuming a range of input column densities and ionization parameters. We fit instead the simulated spectra with a simple cold absorption power-law model that is the standard practice in X-ray surveys. We find that the fraction of absorbed AGN should fall with luminosity as $L^{-0.16\\pm0.03}$ in rough agreement with the observations. Furthermore, this apparent decrease in the obscuring material is consistent with the dependence of ...
The aqueous fraction (AF) of an ethanolic extract from Chrysanthemum indicum was evaluated for analgesic activity in mice using chemical and thermal models of nociception. Given orally, AF at doses of 300 and 600 mg/kg produced significant inhibitions on chemical nociception induced by intraperitoneal acetic acid, subplantar formalin/capsaicin injections and on thermal nociception in the tail-flick test and in the hot plate test. In the pentobarbital sodium-induced sleeping time test and the open-field test, AF neither significantly enhanced the pentobarbital sodium-induced sleeping time nor impaired the motor performance, indicating that the observed analgesic activity was unlikely due to sedation or motor abnormality. In a measurement of core body temperature, AF did not affect temperature within 80 min. Moreover, the effective dose (600 mg/kg) also showed no toxicity within 7 days. These results suggested further that AF produced analgesic activity possibly ...
The refrigerant two-phase flows in a capillary tube and a distributor used in a compression-type refrigerator were visualized by real-time neutron radiography. The thermal neutron radiography system of JRR-3M at the Japan Atomic Energy Research Institute was used. In the visualization experiments of the two-phase flow in the capillary tube of 2 mm I.D., a cooled CCD camera was used, and the axial one-dimensional distributions of void fraction were measured. For the distributor, a high sensitivity video camera with a silicone intensified target tube was used. From the visualized images, the refrigerant behaviors in the distributor were clearly shown, and the liquid fraction in each tube was measured. As a result, it was shown that the refrigerant behaviors in the distributor effected the distributing performance of the refrigerant flow.
Constrained least-squares techniques have been used to produce a well known class of image restoration algorithms. These techniques typically involve minimizing a linear operator on a vector representation of an image, subject to a constraint. For cases where an equality constraint is appropriate the method of Lagrange multipliers can be used to produce a restored image. In this work a fractal textural model, fractional Brownian motion, is used to represent images of interest. Using a variance fractal dimension estimator a non-linear operator, that represents the squared difference between the fractal dimension of the restored image and on a priori value is minimized, subject to the constraint that the norm of the residual between the restored image and available measurement equal the norm of the additive noise.
We present results from a kinetic Monte Carlo simulation of boron transient enhanced diffusion (TED) in silicon. Our approach avoids the use of phenomenological fits to experimental data by using a complete and self-consistent set of values for defect and dopant energetics derived mostly from {ital ab initio} calculations. The results predict that, during annealing of 40 keV B-implanted Si at 800{degree}C, there exists a time window during which all the implanted boron atoms are substitutional. At earlier or later times, the interactions between free silicon self-interstitials and boron atoms drive the growth of boron clusters and result in an inactive boron fraction. The results show that the majority of boron TED takes place during the growth period of interstitial clusters and not during their dissolution. {copyright} {ital 1998 American Institute of Physics.}
We present results from a kinetic Monte Carlo simulation of boron transient enhanced diffusion (TED) in silicon. Our approach avoids the use of phenomenological fits to experimental data by using a complete and self-consistent set of values for defect and dopant energetics derived mostly from ab initio calculations. The results predict that, during annealing of 40 keV B-implanted Si at 800 degree C, there exists a time window during which all the implanted boron atoms are substitutional. At earlier or later times, the interactions between free silicon self-interstitials and boron atoms drive the growth of boron clusters and result in an inactive boron fraction. The results show that the majority of boron TED takes place during the growth period of interstitial clusters and not during their dissolution. copyright 1998 American Institute of Physics.
We address the deviations of the scaling relations of elliptical galaxies from the expectations based on the virial theorem and homology, including the "tilt" of the "fundamental plane" and the steep decline of density with mass. We show that such tilts result from dissipative major mergers once the gas fraction available for dissipation declines with progenitor mass, and derive the scaling properties of the progenitors. We use hydrodynamical simulations to quantify the effects of major mergers with different gas fractions on the structural properties of galaxies. The tilts are driven by the differential shrinkage of the effective stellar radius as a function of dissipation in the merger, while the correlated smaller enhancements in internal velocity and stellar mass keep the slope of the velocity-stellar mass relation near V \\pr M_*^{1/4}. The progenitors match a straightforward model of disc formation in LCDM haloes. Their total to stellar ...
Separation of the bulk soluble chemical salts from the insoluble metal hydroxides and radionuclides is central to the strategy of disposing Hanford tank waste. Sludge washing and caustic leaching have been selected as the primary methods for processing the 230 million L (61,000,000 gal) of Hanford tank waste. These processes are very similar to those selected for processing waste at the West Valley Site in New York and the Savannah River Site in South Carolina. The purpose of sludge washing is to dissolve and remove the soluble salts in the waste. Leaching of the insoluble solids with caustic will be used to dissolve aluminum hydroxide and chromium hydroxide, and convert insoluble bismuth phosphate to soluble phosphate. The waste will be separated into a high-level solids fraction and a liquid fraction that can be disposed of as low-level waste after cesium removal. The washing and leaching operations involve batchwise mixing, settling, and ...
A renewed interest in chemical fractionation of soil organic matter (SOM) originates from the premise that it enables to isolate labile SOM from SOM protected through mineral binding and recalcitrant SOM. Both selective removal of labile non-bound SOM through oxidation or hydrolysis as well as selective removal of minerals and attached SOM are often applied. Molecular-level SOM characterization by means of temperature resolved Pyrolysis-Field Ionization Mass Spectroscopy analysis (Py-FIMS) was used here as an approach to obtain insight into the fate of SOM upon wet chemical treatment with regard to composition and thermal stability. The applied sequential chemical treatment with 6% NaOCl and 10% HF yielded similar sizes in stable SOM fractions between sandy semi-native heathland and cultiv...
This patent describes the producing of a refractory metal wherein a sponge refractory metal is produced as an intermediate product by the use of magnesium with the incidental production of magnesium chloride, and wherein residual magnesium is separated from the magnesium chloride and from refractory metal to a vacuum distillation step which fractionally distills the magnesium, the magnesium chloride, and the metal sub-chlorides; the steps of: recovering fractionally distilled vapors of magnesium chloride and metal sub-chlorides from a sponge refractory metal; separately condensing the vapors as separately recovered; and recycling the separately recovered magnesium at a purity of at least about 96%.
The authors have performed I-123 IMP single- photon emission CT (SPECT) brain imaging on seven mildly demented patients with acquired immunodeficiency syndrome (AIDS) and on seven normal subjects. Pixel-intensity histograms have been analyzed for the fraction of pixels in the lowest quartile of the intensity range. This fraction (F) averaged 17.7% (standard deviation [SD] = 4.3) in the AIDS group and 12.6 (SD = 4.7) in the normal group (P <.05). Regression analysis of neuropsychological testing (NPT) scores vs F yielded a correlation coefficient of.71. The presence or degree of atrophy did not correlate with F or NPT scores.
Dusty primordial disks surrounding young low-mass stars are revealing tracers of stellar and planetary formation. The evolution and lifetime of these disks define the boundary conditions of the mechanisms of planet formation. Stellar companions, however, can significantly change this evolution through their tidal interactions. Stellar evolution and planet formation in binaries have to respond to an environment of truncated, quickly disappearing disks--very different compared to an isolated star environment. In order to investigate details of the influence of binarity on circumstellar disk evolution, we obtained adaptive optics supported near-infrared imaging and spectroscopy of the individual components of 22 low-mass binaries in the well-known Orion Nebula Cluster. Brackett gamma emission, which we detect in several systems, is used as a tracer for the presence of an active accretion disk around each binary component. We find a low fraction of accreting binary ...
Abstract: The recent National Academy of Sciences report on forensic sciences states that the study of fire patterns and debris in arson fires is in need of additional work and eventual standardization. We discuss a recently introduced method that can provide predicted evaporation patterns for ignitable liquids as a function of temperature. The method is a complex fluid analysis protocol, the advanced distillation curve approach, featuring a composition explicit data channel for each distillate fraction (for qualitative, quantitative, and trace analysis), low uncertainty temperature measurements that are thermodynamic state points that can be modeled with an equation of state, consistency with a century of historical data, and an assessment of the energy content of each distillate fraction...
The authors describe a new method which makes it possible to determine the radial distribution of the diffuse component of galactic gamma rays outside the solar circle. They use the observation that a good correlation exists between gamma-ray intensities and total column densities of the local interstellar gas and that the fractional column density of H_2<0.1 HI outside the solar circle. Thus the gamma-ray intensities are shown to be proportional to N(HI). The authors use the kinematics of the HI to determine the distances from which various fractions of the emission originate in the second and third galactic quadrants. Preliminary results of our analysis show that a significant flux of gamma rays originates from distances as large as 18 kpc from the galactic centre. (Auth.).
Theoretical investigations of fatty acids as a phase change material (PCM) for energy storage system have been conducted in this study. The selected fatty acids were capric acid, lauric acid, myristic acid, palmitic acid and stearic acid. For the two-dimensional simulation model based on the enthalpy approach, calculations have been made for the melt fraction with conduction only. Glass, stainless steel, tin, aluminium mixed, aluminium and copper were used as heat exchanger materials in the numerical calculations. Theoretical results show that capric acid was found good compatibility with latent heat storage system. The large value of thermal conductivity of heat exchanger materials did not make significant contribution on the melt fraction. (author)
A model for risk and reliability analysis of complex multifunctional production process systems is presented. The model employs Monte-Carlo and Markov Chain algorithms that uses a weighted index to train and simulate the fuzzy hazard data sets which represents failure outcomes of risk component transient and non-transient systems. Early simulation results shows that hazard rates and the risk of containment loss from typical floating production and storage offloading (FPSO)-Riser system for the risk components in parallel or series increases exponentially with time and decreases as safety ratings fraction increases. The reliability value decreases with time and safety fraction (SFAC) for all fuzzy hazard classifications. The results of the computed mean time before repair (MTBR) show that t...
The petroleum ether fraction (PEF) from the EtOH extract of flowers and buds of Chrysanthemum indicum was evaluated on antinociception in mice using chemical and thermal models of nociception. PEF administered orally at doses of 188 and 376mg/kg produced significant inhibitions on chemical nociception induced by intraperitoneal acetic acid, subplantar formalin or capsaicin injections and on thermal nociception in the tail-flick test and the hot plate test. In the pentobarbital sodium-induced sleep time test and the open-field test, PEF neither enhanced the pentobarbital sodium-induced sleep time nor impaired the motor performance, indicating that the observed antinociception was unrelated to sedation or motor abnormality. In a measurement of core body temperature, PEF did not affect temper...
Samples of Fe78B13Si9 (Metglas 2605 TCA) and Fe77Cr2B16Si5 (Metglas 2605 S3A) were exposed to pulsed excimer laser irradiation at repetition rates of 15, 25 and 50Hz. The occurrence of out-of-plane magnetic anisotropy, changes in the average hyperfine magnetic field and width of the hyperfine field distribution were evidenced by transmission Mossbauer spectroscopy. The variation of the recoilless fraction with laser processing parameters was derived from the simultaneous recording of Mossbauer spectra using a stainless steel etalon as a dual absorber. Conclusions on the onset of long-range magnetic order were formulated.
Heme peroxidases are a class of multifunctional redox-active proteins found in all organisms. We recently cloned, expressed, and characterized an ascorbate peroxidase from Leishmania major (LmAPX) that was capable of detoxifying hydrogen peroxide. Localization studies using green fluorescent protein fusions revealed that LmAPX was localized within the mitochondria by its N-terminal signal sequence. Subcellular fractionation analysis of the cell homogenate by the Percoll density-gradient method and subsequent Western blot analysis with anti-LmAPX antibody further confirmed the mitochondrial localization of mature LmAPX. Submitochondrial fractionation analysis showed that the mature enzyme (?3.6?kDa shorter than the theoretical value of the whole gene) was present in the intermembrane space ...
Coronary angiography has provided an unrivalled appreciation of coronary anatomy fostering a far greater appreciation of the extent of atherosclerotic disease. However, the subjectivity of coronary angiography at determining the extent of plaque has been exposed with IVUS. Indices of coronary physiology have provided valuable adjunctive information as to the physiological importance of specific lesions. Fractional flow reserve is an established method for evaluating the significance of epicardial stenoses. Fractional flow reserve guided percutaneous coronary intervention is associated with improved outcomes when compared to a conventional angiographic guided strategy, particularly in intermediate lesions. The use of coronary physiology in the cath lab represents a new avenue to guide appro...
Abstract:- An experimental investigation was carried out to evaluate the quality of-taralli-as a function of the type of oil used in their dough formulation. To this end, 4 types of oil (extra virgin olive oil, olive oil, olive-pomace oil, and refined palm oil) were utilized to prepare-taralli-to investigate on the lipid fraction degradation and evaluate the-taralli-acceptability by consumers. The data obtained pointed out that-taralli-manufactured with extra virgin olive oil were significantly more appreciated than those made with refined oils due to their visual appearance and odor. Moreover, with respect to the other kinds of oil, the use of extra virgin olive oil led to significantly lower values (P-< 0.05) of specific absorption at 232 and 270 nm (K232 and K270, respectively) and of t...
Dark Matter annihilation (DMA) may yield an excess of gamma rays and antimatter particles, like antiprotons and positrons, above the background from cosmic ray interactions. The excess of diffuse Galactic Gamma Rays from EGRET shows all the features expected from DMA. The new precise measurements of the antiproton and positron fractions from PAMELA are compared with the EGRET excess. It is shown that the charged particles are strongly dependent on the propagation model used. The usual propagation models with isotropic propagation models are incompatible with the recently observed convection in our Galaxy. Convection leads to an order of magnitude uncertainty in the yield of charged particles from DMA, since even a rather small convection will let drift the charged particles in the halo to outer space. It is shown that such anisotropic propagation models including convection prefer a contribution from DMA for the antiprotons, but the rise in the positron ...
Asphaltenes precipitated from an Arabian Mix vacuum residue were hydrocracked in a batch autoclave at 435 and 460{degree}C for 5-90 min. Experiments without catalyst, with modified red mud and with an industrial Co Mo/Al{sub 2}O{sub 3} catalyst were compared. The products were fractionated into gas, naphtha, oil, asphaltenes and coke. Feed asphaltenes and several product fractions were characterised by elemental analysis, by average molecular mass and by {sup 1}H n.m.r. Due to the hydrogenation activity, both catalysts caused - with similar efficiency - the decrease of coke formation and the increase of quantity and quality of oil. 21 refs., 9 figs., 5 tabs.
We demonstrate experimentally that the route to a jammed state for a set of bi-dispersed frictional disks, subjected to uni-axial compression from a random initial unjammed state, consists of a consolidation state, a fragile jammed state, and finally a rigid jammed state. In the consolidation regime, the pressure on the sides increases very slowly with the packing fraction {phi} and there are no detectable stress chains. In the fragile jammed state, stress chains are visible, the pressure increases exponentially with {phi}, and the fraction of moving disks drops exponentially. Eventually, a final regime where particle displacements are below our resolution and the pressure varies approximately linearly with {phi} is reached. We argue that this scenario is generic for ather mal frictional compressed particles.
Aim: This study was performed: 1) to assess the relationship between blood flow velocity in the internal carotid artery (CBFICA) and pial artery pulsation (cc-TQ) and 2) to evaluate flow-induced changes in pial artery compliance. Methods: Experiments were performed on 10 crossbred male rabbits. Heart rate (HR), blood pressure (BP), left ventricle ejection fraction (LVEF), CBFICA, the systolic-diastolic blood volume fraction in the brain circulation (CBFSDF) and cc-TQ were recorded after glucagon and acetazolamide administration. cc-TQ was measured with near-infrared transillumination back scattering sounding (NIR-T/BSS), LVEF and CBFSDF with gated scintigraphy and BP and CBFICA with electromagnetic pressure and flow transducers, respectively. Doses of drugs were chosen to exert a haemodyna...
Measurements of branching fractions and CP-asymmetries of B^{-} \\rightarrow D^{0}K^{-} modes allow a theoretically-clean extraction of the CKM angle \\gamma. The method proposed by Atwood, Dunietz and Soni (ADS) makes use of a decay chain where color and Cabibbo suppression interfere, which produces large CP-violating asymmetries. The CDF experiment reports the first measurement at a hadron collider of branching fractions and CP-asymmetries of suppressed B^{-} \\rightarrow D^{0}h^{-} signals, where h is \\pi or K. Using 5.0 fb^{-1} of data we found a combined significance exceeding 5\\sigma and we determined the ADS parameters with accuracy comparable with B-factories.
In this paper, we show how to improve and extend the integration by fractional expansion technique (IBFE) by applying it to certain families of scalar massive Feynman diagrams. The strategy is based on combining this method together with the integration by parts technique. In particular, we want to calculate certain Feynman diagrams which have a triangle loop as a subgraph. The main idea is to use the integration by parts technique in this subgraph in order to simplify the topology of the original diagram in which it is immersed, using then, in a second step, the IBFE technique. The result we have obtained, after the application of both techniques, represents a simplification in the complexity of the solution, compared with having used only the IBFE technique.
Extraction of rare earths (La, Ce, Pr, Eu, Gd, Er, Yb) from nitrate solutions by melts of carboxylic acids of the C/sub 17/-C/sub 20/ fraction and stearic acid with paraffin, depending on the temperature (60-90 deg), phase contact time and their volume ratio (O:B from 1:5 up to 1:100), pH of the aqueous phase (2-6), rare earth concentration (10/sup -6/-10/sup -3/ m) is studied. It is shown that in the whole concentration range investigated rare earths are extracted quantitatively into the carboxylic acid melt of C/sub 17/-C/sub 20/ fraction at the equilibrium value of pH>=3.8, while into the melt of 0.1 M stearic acid in paraffin at pH>=4.5.
In this research, the interactive effect of grain and specimen sizes on the flow stress of sheet metal in microforming is investigated via the tensile test of pure copper and numerical modeling. Models based on different assumptions are proposed to analyze the size effect phenomenon. It is found that the flow stress decreases linearly with the decrease of the ratio of specimen to grain sizes. The grain boundary thickness decreases and its volume fraction increases with the decrease of grain size. The variation of grain boundary thickness is not proportional to the variation of grain size. Furthermore, the fraction of grain boundary increases with the strain and the ratio of specimen to grain sizes. Based on the FE simulation, it is found that the simulated flow stress, which is modeled bas...
Measurements of the statistical characteristics of channel wall static pressure fluctuations in parallel one-component boiling flow are reported. The measurements span a wide range of local subcooling and vapor volume fraction, and correspond to flow regimes ranging from highly subcooled bubbly to saturated slug-annular. Vapor volume fraction measurements at the pressure measurement station are also reported in conjunction with visual observation of the flow structure. Variation of static pressure fluctuation intensity and spectral content with local thermal-hydraulic condition is demonstrated. Finally, it is suggested that diagnosis of local two-phase flow regime on the basis of (i) statistical characteristics of the pressure data, and (ii) time trace of pressure signal, may be possible. 15 refs.
Purpose: In this paper, we present an alternative to the originally proposed technique for the delivery of spatially fractionated radiation therapy (GRID) using multi-leaf collimator (MLC) shaped fields. We employ the MLC to deliver various pattern GRID treatments to large solid tumors and dosimetrically characterize the GRID fields. Methods and materials: The GRID fields were created with different open to blocked area ratios and with variable separation between the openings using a MLC. GRID designs were introduced into the Pinnacle3 treatment planning system, and the dose was calculated in a water phantom. Ionization chamber and film measurements using both Kodak EDR2 and Gafchromic EBT film were performed in a SolidWater phantom to determine the relative output of each GRID design as w...
b-carotene, a natural antioxidant, beneficial form human health prospective. In this study we had examined the recovery of b-carotene form mesoporous carbon coated monolith (MCCM) by batch process. Desorption kinetics and isotherm studies were carried out by using n-hexane as an eluent. Isotherm studies showed better applicability of Langmuir model. The first-order two-compartment three-parameter kinetics model as a function of initial loading concentration and reaction temperature was applied. It was observed that b-carotene desorption process is controlled by both rapid and slow desorption. Results showed that the slow desorption fraction increases from 0.8446 to 0.9007 with increase in initial loading concentration from 10.83 to 39.72mg/g while, the slow desorption fraction decreases fr...
The black carbon continuum is composed of a series of carbon-rich components derived from combustion or metamorphism and characterized by contrasting environmental behavior and susceptibility to oxidation. In this work, we present a micro-scale density fractionation method that allows isolating the small quantities of soot-like and graphitic material usually found in natural samples. Organic carbon and {delta}{sup 13}C mass balance calculations were used to quantify the relative contributions of the two fractions to thermally-stable organic matter from a series of aquatic sediments. Varying proportions of soot-like and graphitic material were found in these samples, with large variations in {delta}{sup 13}C signatures suggesting important differences in their origin and/or dynamics in the environment.
The experimental densities, {rho} for binary mixtures of (N-acetylmorpholine + benzene, +toluene, +ethylbenzene, and +mesitylene) have been measured at temperatures from (293.15 to 343.15) K and atmospheric pressure over the whole mole fraction range. From these results, excess molar volumes V{sup E} have been calculated and fitted to the Redlich-Kister polynomial equation. The V{sup E} values are negative over the whole mole fraction range and at all temperatures. Thermal expansion coefficients {alpha}{sub i}, apparent molar volumes V{phi}{sub i}, and partial molar volumes at infinite dilution V{sub i}{sup {infinity}} have been calculated. The variation of these properties with composition and temperature of the binary mixtures are discussed in terms of molecular interactions.
Purpose of this work is to evaluate the effectiveness and role of CT in blunt diaphragmatic injuries by reviewing our 8-year experience. It is reviewed the preoperative CT findings of 35 patients with surgically confirmed diaphragmatic rupture. Surgical repair was performed in the acute setting (within 12 hours of trauma) in 22 cases, and late (8 months-5 years) in 13 cases. Twenty-eight patients (80%) were examined with conventional CT and 7 (20%) with Helical CT. Of the 13 patients examined long after trauma, the left hemi diaphragm was ruptured in 12 cases (with visceral herniation in 4), and the right hemi diaphragm in 1, with no herniation. The diaphragmatic rent was found in the dome (15 cases, 43%), muscolotendinous junction (11 cases, 31%), muscular portion (8 cases, 23%), and at the muscular attachments on the ribs (1 case, 3%). As for the site of diaphragmatic injury, CT never depicted the diaphragmatic rent in the dome and at the muscolotendinous ...
The aim of this study was to evaluate the automated urine test strip analyzer Aution Max AX 4280 which uses strips able to measure 12 urinary parameters. For precision study, we considered glucose, protein, blood, leukocytes, nitrite, and pH and the four first were compared with usual methods: chemical measurement or microscopic examination. Reproducibility of the semi quantitative results was determined as the proportion of results falling into the same concentration range. Within-run reproducibility assessed using urine specimens were between 83% and 96%. Between day on quality controlled materials, it was higher (96%), and leukocytes were shared between two classes 250 and 500 cells/microL. For glucose and proteins, linearity was good and comparison with quantitative methods yielded high correlation. The false negative fraction was low and there was no false positive results. For blood, fraction of false positive was 7.5% for 0.3 mg/L of ...
Real-time neutron radiography is being evaluated for studying the dynamic behavior of two-phase flow and for measuring void fraction in vertical and inclined water ducts. This technique provides a unique means of visualizing the behavior of fluid flow inside thick metal enclosures. An air-water flow system was constructed to simulate vapor conditions encountered in a fluid flow duct. Air was injected into the bottom of the duct at flow rates up to 0.47 {ell}/s (1 ft{sup 3}/min). The water flow rate was varied between 0 and 3.78 {ell}/min (0 to 1 gal/min). The experiments were performed at the Pennsylvania State University nuclear reactor facility using a real-time neutron radiography camera. With a thermal neutron flux on the order of 10{sup 6} n/cm{sup 2}{center_dot}s{sup {minus}1} directed through the thin duct dimension, the dynamic behavior of the air bubbles was clearly visible through 5-cm (2-in.)-thick aluminum support plates placed on both sides of the duct ...
Real-time neutron radiography is being evaluated for studying the dynamic behavior of two phase flow and for measuring void fraction in vertical and inclined water ducts. This technique provides a unique means of visualizing the behavior of fluid flow inside thick metal enclosures. To simulate vapor conditions encountered in a fluid flow duct, an air-water flow system was constructed. Air was injected into the bottom of the duct at flow rates up to 0.47 I/s (1 cfm). The water flow rate was varied between 0--3.78 I/m (0--1 gpm). The experiments were performed at the Pennsylvania State University nuclear reactor facility using a real-time neutron radiography camera. With a thermal neutron flux on the order of 10{sup 6}n/cm{sup 2}/s directed through the thin duct dimension, the dynamic behavior of the air bubbles was clearly visible through 5 cm (2 in.) thick aluminum support plates placed on both sides of the duct wall. Image analysis techniques were employed to ...
Real-time neutron radiography is being evaluated for studying the dynamic behavior of two-phase flow and for measuring void fraction in vertical and inclined water ducts. This technique provides a unique means of visualizing the behavior of fluid flow inside thick metal enclosures. An air-water flow system was constructed to simulate vapor conditions encountered in a fluid flow duct. Air was injected into the bottom of the duct at flow rates up to 0.47 ell/s (1 ft"3/min). The water flow rate was varied between 0 and 3.78 ell/min (0 to 1 gal/min). The experiments were performed at the Pennsylvania State University nuclear reactor facility using a real-time neutron radiography camera. With a thermal neutron flux on the order of 10"6 n/cm"2#centre dot#s"-"1 directed through the thin duct dimension, the dynamic behavior of the air bubbles was clearly visible through 5-cm (2-in.)-thick aluminum support plates placed on both sides of the duct wall. Image analysis ...
New RNAA determinations of Ba, Sr, Zr, U, Re, Pd, Ag, Zn and Se and INAA measurements of Lu are added to published data for 21 other elements in the same suite of ten samples. On the average, 21 refractory elements are not significantly fractionated from one another. The mean of their enrichment factors relative to C1 chondrites is 17.5 +- 0.4, indicating that the high-temperature condensate inclusions represent 5.7 wt% of the total condensable matter. Os, Ir, Ru, Re and most of the W condensed in one or more refractory siderophile element alloys along with small fractions of the Pd, Co, Au and Ag. The bulk of the Eu and Sr condensed in solid solution in melilite. Sc, Zr, Hf, Ta, U and the remaining REE condensed in a phase whose abundance in the inclusions in negatively correlated with that of melilite, either diopside or one or more minor or trace phases, including perovskite. Ba condensed in a different phase, separately from all these ...
Electrophoresis in a sucrose gradient at pH values between 5 and 8 separated housefly DDT [1,1,1-trichloro-2,2-bis-(p-chlorophenyl)ethane] dehydrochlorinase into two major fractions....Full Text Available
The present state of knowledge on the influence of stray radiation on image quality and its physical description and quantification is summarized. Experimental results on the influence of physical parameters on the fraction of scattered radiation and the effect of scatter reduction by air gap technique and secondary radiation grids are committed. Open theoretical and practical problems and the limitations of common methods of scatter reduction are pointed out. (author).
Using the Relativistic Mean Field Theory (RMF) it is shown that different proton fraction which is directly connected with the neutron excess and with the asymmetry of the system affects proto-neutron stars parameters and changes their composition. The obtained form of the equation of state allows to construct the mass-radius relations and shows that the increasing asymmetry creates more compact stars. The inclusion of {delta} meson together with nonlinear vector meson interaction terms and magnetic field make this effect even stronger.
When the vehicle-treated, sham-operated mice underwent heat stress, the fraction survival and core temperature at +4 h of body heating were found to be 5 of 15 and 34.4°C ± 0.3°C,...Full Text Available
The main features are presented of a computer programme for 3-D thermohydraulic and thermodynamic analysis of the PGV-1000 horizontal steam generator used at the Temelin NPP. The programme provides analyses of primary side hydraulics, heat exchange behavior and the steam generator secondary side thermohydraulics and thermodynamics. Given are calculated data on the circulation flow rate, void fraction, heat transfer dynamics and the swelled level. (Z.S.) 9 figs.
This study investigated relationships between molecular weight distributions of unreduced grain proteins and grain, flour, and end-use quality characteristics of soft white winter wheats grown in Oregon. Absorbance area and area % values of protein fractions separated by size exclusion HPLC (SE-HPL...
The recovery of noble metals from the quaternary Mo-Ru-Rh-Pd alloy in the simulated insoluble residue was studied by means of Pb extraction and the recovery yield was found to be more than 90% for Ru, Rh and Pd. The recovery yield of Mo was very small due to the oxidative vaporization in air. The decontamination factor for Ce as a stand-in of Pu was determined to be around 200 for one stage. These results on the recovery yields of noble metals from the quaternary alloy and the decontamination factor for Ce are in good agreement with those for the ternary Mo-Ru-Pd alloy previously reported by the present authors. The mutual separation of noble metal elements recovered in Pb button was examined by means of re-extraction with molten Zn and the dissolution in boiling 3M or 6M nitric acid solution. The dissolution fractions of Pd and Rh recovered in the Pb button in boiling 3M and 6M nitric acid solution for 12 h were about 90 and 30%, respectively, and that of Ru was ...
To evaluate a dose conversion factor from the `Working Level of Month` (WLM) of radon to the absorbed dose (mGy), the quality of radon and its progeny was assessed, and exposures controlled for each deposition region were planed as follows: 1) exposure of radon gas to the entire respiratory tract, 2) exposure of `unattached` fractions to the upper respiratory tract, 3) exposure of `attached` fractions onto ultrafine particles to the deep lung, 4) exposure of `attached` fractions onto fine particles to the lower respiratory tract, 5) exposure of `attached` fractions onto coarse particles to the upper respiratory tract. In this preliminary study, a prototype exposure system of radon and its progeny for small rodents was designed. A whole body exposure chamber with a volume of about 0.5 m{sup 3} was used, which it held 20 rats. The aging and mixing chamber separated by the exposure chamber had a volume of ...
The wavefunction of a positron in ReO is calculated using the augmented-plane-wave method. Due to the loosely-packed structure of ReO_3, the ground-state GAMMA_1 wavefunction exhibits a marked anisotropy particularly around the oxygen ions, and a large fraction of a positron is distributed in the interstitial region. Experimental results of the positron annihilation 2#gamma#-correlations and the positron annihilation rates in ReO_3 are discussed based on the positron wavefunction. (orig.).
Histone H3 mRNAs were found in polyA(+) fractions of total RNA prepared from alfalfa plants, calli and somatic embryos. The sequence analysis of cDNAs revealed the presence of a polyA tail on independent...Full Text Available
The possibility of separation in plasma-mass-separator POMS-E-3 spent nuclear fuel (SNF) in 3 fractions: transuranic elements, and two groups of fission products. New scheme of compact energy-mass analyzer for monitoring the separation process spent nuclear fuel in the POMS-E- 3 offered.
To suppress space charge blowup in an ion beam passing through a photoneutralizer, it is necessary to introduce some background gas. An analysis is presented of the neutralization of a high-energy, >200-keV negative deuterium ion beam, exposed to photodetachment while in the presence of deuterium. With a gas thickness of <0.01 Torr.cm, the neutral fraction in the output beam is found to be about the same as that gotten from the photoneutralizer operating in vacuum. Neutral atom beam injection for plasma heating is discussed.
We study by means of Quantum Monte Carlo simulations based on the Worm Algorithm the low temperature (down to T = 0.05 K) properties of parahydrogen clusters comprising up to 40 molecules. Three different intermolecular interactions are employed: the Silvera-Goldman, the Buck and the Lennard-Jones potential. Despite important discrepancies observed in the numerical estimates of energy and superfluid fraction, the mechanism by which clusters melt at low T is independent of the particular choice of the potential, whose only effect is to alter the temperature scale.
Results are given of numerical simulation of three-dimensional pattern of flow of a two-phase steam-water mixture in the house of a PGV-1000 horizontal steam generator obtained using the BAGIRA best-estimate thermohydrodynamic computer codes. The space distributions of velocities and local void fractions in the steam generator housing for different modes of operation of power-generating unit are calculated and compared with available experimental data.
Results are given of numerical simulation of three-dimensional pattern of flow of a two-phase steam-water mixture in the house of a PGV-1000 horizontal steam generator obtained using the BAGIRA best-estimate thermohydrodynamic computer codes. The space distributions of velocities and local void fractions in the steam generator housing for different modes of operation of power-generating unit are calculated and compared with available experimental data.
Recent nucleosynthesis calculations of Type II supernovae using advanced neutrino transport determine that the early neutrino winds are proton-rich. However, a fraction of the ejecta emitted at the same time is composed of neutron-rich pockets. In this paper we calculate the nucleosynthesis contribution from the neutron-rich pockets in the hot convective bubbles of a core-collapse supernova and show that they do not contribute significantly to the total nucleosynthesis.
Results of calculation of steady thermal-hydraulic characteristics of PVG-440 horizontal steam generator are presented. Steam flows in selected sections are compared to data provided by OKB Gidropress Calculated vapor void fractions are compared to measured ones. (orig.) (3 refs., 3 figs., 8 tabs.).
Results of calculation of steady thermal-hydraulic characteristics of PVG-440 horizontal steam generator are presented. Steam flows in selected sections are compared to data provided by OKB Gidropress Calculated vapor void fractions are compared to measured ones. (orig.) (3 refs., 3 figs., 8 tabs.).
Lead tungstate crystals doped with small fractions of praesodynium or molybdenum have been tested in beams of high-energy electrons. The goal of these tests was to study the effects of such dopants on the capability to separate the signal components deriving from the Cherenkov and scintillation light generated by the beam particles. These studies were carried out in view of the possible application of such crystals in dual-readout calorimeters.
The catalytic performance of alkaline-treated zeolite H-ZSM-5 in the conversion of methanol to gasoline has been studied. After treatment with 0.20M NaOH, the total conversion capacity increased by a factor of 3.3, and the selectivity towards the gasoline fraction increased by a factor of 1.7. Physical characterization indicated the formation of mesopores and improved crystallinity.
This research has two main goals; (1) to quantify mechanisms for radon entry into homes of different types and to determine the fraction of indoor radon attributable to each source and (2) to model and calculate the dose (and therefore alpha particle fluence) to cells in the human and animal tracheobronchial tree that is pertinent to induction of bronchogenic carcinoma from inhaled radon daughters.
DOE`s Office of Environmental Management (EM) is responsible for managing waste and cleaning up contamination at DOE sites across the United States. A substantial fraction of the work performed for EM includes sampling and analysis activities. This paper outlines the Sample Management Programs, achievements to date, and future directions.
The feasibility of using a thermoplastic-powder metallurgy technique for the fabrication of porous niobium rods was investigated. Some early problems were overcome to successfully extrude the polymer coated niobium powder into long lengths. The effects of certain process variables were investigated. Residual porosity and extrusion pressure were found to be regulated by the polymer fraction. The procedures for taking the extruded polystyrene--niobium rods through the heat treatments to the final, tin infiltrated stage are explained.
From the alkalised crude extract of Symphytum cordatum (L.) W.K. roots, pyrrolizidine alkaloids (PAs) were extracted as free tertiary bases and polar N-oxides in a merely one-step liquid-liquid partitioning (LLP) in separation funnel and subsequently pre-fractionated by preparative multiple-development (MD) thin-layer chromatography (TLC) on silica gel plates. In this way three alkaloid fractions of different polarities and retention on silica gel plates were obtained as: the most polar N-oxides of the highest retention, the tertiary bases of medium retention, and diesterified N-oxides of the lowest retention. The former fraction was reduced into free bases by sodium hydrosulfite and purified by LLP on Extrelut-NT3 cartridge. It was further analysed together with the two other fractions by high-performance liquid chromatography (HPLC)-ion-trap mass spectrometry with atmospheric pressure chemical ...
Using 14M $\\psi (2S)$ events collected at BESII, the branching fraction of $\\psi (2S)\\to \\tau ^{+}\\tau ^{-}$ is measured to be $Br_{\\tau \\tau}=(3.10\\pm 0.21\\pm 0.38)\\times 10^{-3}$, where the first error is statistical and the second is systematic.
Loss of organic matter is one of the main forms of soil degradation in Mediterranean agricultural soils, and external sources of organic matter are required to improve soil properties. the two-phase centrifugation system in the olive-oil extraction industry produces a large amount of olive mill waste sludge (TPOMW) which can be used to add organic C to degraded soils. (Author)
One hundred and thirty-seven lung cancer patients (123 non-small-cell lung cancers (NSCLC), 10 small-cell lung cancers (SCLC) and four carcinoid tumours) who underwent surgery in an attempt at complete...Full Text Available
This book presents the papers given at a conference on two-phase flow. Topics considered at the conference included the thermal hydraulics of a feedwater pipe breakage, pressure losses, measurement of void fraction in a rod bundle, laminar filmwise condensation, natural circulation, flow models, bubble dynamics, cavitation, water hammer, and heat transfer augmentation.
This book presents the papers given at a conference on two-phase flow. Topics considered at the conference included the thermal hydraulics of a feedwater pipe breakage, pressure losses, measurement of void fraction in a rod bundle, laminar filmwise condensation, natural circulation, flow models, bubble dynamics, cavitation, water hammer, and heat transfer augmentation.
Six major use pesticides (Atrazine, Dicamba, Isoproturon, Lindane, Paraquat and Trifluralin) with differing physico-chemical properties were evaluated for the significance of 'bound' or non extractable residue formation. Investigations were carried out in purpose-built microcosms where mineralization, volatilisation, 'soil water' extractable and organic solvent extractable residues could be quantified. Extractable residues were defined as those accessible by sequential extraction where the solvent used became increasingly non-polar. Dichloromethane was the 'harshest' solvent used at the end of the sequential extraction procedure. {sup 14}C-labelled volatilised and {sup 14}CO{sub 2} fractions were trapped on exit from the microcosm. The pesticides were categorised into 3 classes based on their behaviour. (i) Type A (Atrazine, Lindane and Trifluralin) in which ring degradation was limited as was the formation of ...
Experimental and evaluated integral parameters derived from nuclear plus interference differential elastic scattering cross sections are presented for all projectile/target combinations of the particles p, d, t, /sup 3/He, and ..cap alpha... The data include reaction rates, average fractional energy losses per collision and per unit path length, and average laboratory scattering cosines. The resulting parameters are of potential use in analysis of charged-particle transport.
The processes of lung growth, injury, and repair are characterized by alterations in fibroblast synthesis and interstitial distribution of extracellular matrix components. Transforming growth factor beta (TGF-beta), which is postulated to play a role in modulating lung repair, alters the distribution of several matrix components such as collagen and fibronectin. We studied the effect of TGF-beta on the synthesis and distribution of the various glycosaminoglycans (GAGs) and whether these effects may explain its role in lung repair. Human diploid lung fibroblasts (IMR-90) were exposed to various concentrations of TGF-beta (0-5 nM) for variable periods of time (0-18 h). Newly synthesized GAGs were labeled with either (3H)glucosamine or (35S)sulfate. Individual GAGs were separated by size exclusion chromatography after serial enzymatic and chemical digestions and quantitated using scintillation counting. There was a dose-dependent increase in total GAG synthesis with maximal levels ...
Counter-current two-phase flows of air-water in narrow rectangular channels with offset-strip fins have been experimentally investigated in a 760 mm long and 100 mm wide test section with 3.0 and 5.0 mm gap widths. The two-phase flow regime, channel-average void fractions and two-phase pressure gradients were studied. Flow regime transition occurred at lower superficial velocities of air than in the channels without fins. In the bubbly and slug flow regimes, elongated bubbles rose along the subchannel formed by fins without lateral movement. The critical void fraction for the bubbly-to-slug transition was about 0.14 for the 3 mm gap channel and 0.2 for the 5 mm gap channel, respectively. Channel-average void fractions in the channels with fins were almost the same as those in the channels without fins. Void fractions increased as the gap width increased, especially at high superficial velocity of air. ...
The conductance in ferromagnetic Ni nano-wire is quantized in units of 2e{sup 2}/h in the absence of magnetic field, while the units switch to e{sup 2}/h in the magnetic field. The fractional units of 0.7e{sup 2}/h and 1.4e{sup 2}/h with and without magnetic field appear under the application of high bias-voltage. The spin polarization and bias-voltage play an important role in the electric conduction.
Effect of two organic chemicals viz., 2,4-dinitrophenyl hydrazone (C_1) and naphthyl ethylene diamine (C_2) was studied by their application alone and together (Csub(1+2) at the rate of 10 ppm by growing wheat on a loamy soil (Typic ustochrept) containing recently immobilized fertilizes N of "1"5N - urea applied at 60, 120 and 180 ppm N to preceding rice under greenhouse conditions of a rice-wheat sequence. The application of C_1 and C_2 alone; and their combined application (Csub(1+2) produced 12, 15 and 18 per cent higher wheat grain yield over no-chemical application i.e. Co (3.50 g/pot). The chemicals also showed their beneficial effect on utilization of recently immobilized fertilizer N, as was evidenced by significantly higher "1"5N recovery values in wheat with C_1, C_2 and Csub(1+2)(2.84, 3.63 and 3.54 per cent, respectively) than that of Co (2.29 per cent). The soil N fractions were affected by chemical application during wheat as total hydrolyzable N, ...
Several steam generator tube rupture accidents have occurred at plants in the past. In this paper the Computational Multi-Fluid Dynamics (CMFD) investigation of the horizontal steam generator thermal-hydraulics during the tube rupture accident is performed. A guillotine of a steam generator U-tube is assumed with choked flow from the primary to the secondary side of the steam generator. We have computed water and steam velocity fields, steam volume fraction distribution on the steam generator secondary (shell) side, as well as the swell level increase. The simulation results are a support to the safety analyses of the steam generator tube rupture accident. Numerical simulation is performed with the multidimensional multi-fluid modelling approach. The two-phase flow around steam generator tubes in the bundle is modelled by the porous media approach. Interfacial mass, momentum and energy transfer are modelled with the closure laws. The governing equations are solved ...
Piper regnellii (Miq.) C. DC. var. pallescens (C. DC.) Yunck (Piperaceae) is a medicinal plant traditionally used in Brazil to treat infectious diseases. The extracts obtained from the leaves of P. regnellii were investigated for their antifungal activities against the yeasts Candida albicans, C. krusei, C. parapsilosis, and C. tropicalis. The EtOAc extract presented gnificant activity against Candida albicans with MIC at 125 {mu}g mL{sup -1}, and a moderate activity against both C. krusei and C. parapsilosis with MIC at 500 {mu}g mL{sup -1}. Candida tropicalis was not inhibited by this extract at concentrations as high as 1000 {mu}g mL{sup -1}. Based on these findings, the EtOAc extract was fractionated by silica gel column chromatography into nine fractions. The hexane and CHCl{sub 3} fractions showed varied levels of antifungal activity against all test yeasts. Further column chromatography separation of the hexane ...
Results of an augmented-plane-wave calculation of the positron lifetime and the angular-correlation curves for aluminum, both in the vacancy-free crystal and in the crystal with a vacancy, are presented. The environment of the vacancy was simulated by a face-centered-cubic supercell with a volume 27 times that of the standard primitive unit cell of the Al lattice. The calculated positron-vacancy binding energy is 3.36 eV at room temperature. The temperature dependences of the trapping potential, the positron-vacancy binding energy, and the positron lifetime both in the Bloch state and in the vacancy-trapped state, associated only with the static thermal expansion of the lattice, have been calculated. It is found that the fractional increase in positron lifetime in the Bloch state is only approx.80% of the fractional increase in the volume of the lattice. The lifetime in the vacancy-trapped state is also found to vary with temperature, showing a ...
We have recently introduced several important improvements in the measurement of distillation curves for complex fluids. This new method is a significant improvement over current approaches, with features including a composition-explicit data channel for each distillate fraction (for both qualitative and quantitative analysis), trace chemical analysis of each distillate fraction, and a corrosivity assessment of each distillate fraction. In the present contribution, we present the application of the advanced distillation curve method to a bio-derived crude oil prepared from swine manure. One motivation behind the work was to precisely measure the distillation curve of the oil derived from swine manure with our advanced distillation apparatus and compare the bio-derived oil to traditional petroleum crude oils. Then, the information content of the bio-derived oil distillation was extended further with the composition-explicit ...
The Project was started August 1, 1992. During these first two months, the Project Management plan was issued and approved during discussions at the Pittsburgh Energy and Technology Centre. Feed materials for the experimental work (with the exception of the second solvent) have been received. The analytical work up of these feed materials has been completed, and autoclave stability tests with the solvent and solvent fraction have been performed and analyzed. The Project is proceeding on schedule.
The Project was started August 1, 1992. During these first two months, the Project Management plan was issued and approved during discussions at the Pittsburgh Energy and Technology Centre. Feed materials for the experimental work (with the exception of the second solvent) have been received. The analytical work up of these feed materials has been completed, and autoclave stability tests with the solvent and solvent fraction have been performed and analyzed. The Project is proceeding on schedule.
This paper mainly considers the asymptotic stability of interval neutral delay-differential systems, which corrects a technical error in the proof given in [Applied Math. Letters, 16(2003) 1063-1068] by a linear fractional transformation of an interconnection matrix with structured real parametric uncertainties. In addition, a new condition, in terms of the structured singular value, is provided to ensure the stability of the interval system. Finally, an example is given to demonstrate the validity of our criteria.
Total and net energies used harvesting 30-cm billets at 8 t/h were 1 and 0.3 kW x h/t, respectively. Harvested crop had 4% leaves, a 70% mass fraction of billets 30-40 cm long, and a 49/sup 0/ angle of repose. A self-unloading forage wagon with beaters and controls metered billets at 1.5 t/h to feed a juice-expression mill.
In the treatment of prostatic cancer using a newly proposed intermittent multiportal therapy (DIMT), acute reactions, change in tumor marker levels, and complications more than 6 months after treatment were evaluated. From June 1989 to September 1990, 26 patients with prostatic cancer (stage A2, 3 patients; B, 9; C, 2; D, 10; recurrence, 2) were treated. Fifteen patients were followed up for more than one year, with a mean period of 11.6 months. The treatment schedule is 52.5 Gy in 16 fractions in 4 weeks for radical treatment, and 30.0 Gy in 8 fractions in 2 weeks for palliative treatment. The 360 degree rotation about the patient was divided into 16 fractions, and 2 opposing fractions were used in one day as parallel opposed portals to treat the target volume. The fractions were serially treated one per day, so that 8 treatment days produced a total dose of distribution similar to ...
Purpose: We present an update analysis of the multiinstitutional Ewing's sarcoma study CESS 86. Methods and Materials: From January 1986 through June 1991, 177 patients with localized Ewing's sarcoma of bone, aged 25 years or less, were recruited. Chemotherapy consisted of four 9-week courses of vincristine, actinomycin D, cyclophosphamide, and adriamycin (VACA) in low-risk tumors (extremity tumors =# 100 cm"3). Local therapy was an individual decision in each patient and was either radical surgery (amputation, wide resection) or resection plus postoperative irradiation with 45 Gy or definitive radiotherapy with 60 Gy (45 Gy plus boost). Irradiated patients were randomized concerning the type of fractionation in either conventional fractionation (once daily 1.8-2.0 Gy, break of chemotherapy) or hyperfractionated split-course irradiation simultaneously with the VACA/VAIA chemotherapy (twice daily 1.6 Gy, break of 12 days after 22.4 Gy and 44.8 ...
In laser ablation inductively coupled plasma mass spectrometry (LA-ICPMS), the properties of laser-generated aerosols, such as size and composition, are crucial for matrix-independent quantification. In this study, the aerosol particle morphology and elemental composition generated by two state-of-the-art laser systems (ArF excimer nanosecond-UV laser and Ti:sapphire femtosecond-IR laser) were investigated by electron microscopic techniques. Electrostatic sampling of the aerosols directly onto transmission electron microscopy (TEM) grids allowed us to study the morphology and elemental composition of the aerosols using TEM and TEM-EDX (energy dispersive X-ray spectroscopy) analyses, respectively. The results of the electron microscopic studies were finally compared to the LA-ICPMS signals of the main matrix components. The investigations were carried out for non-conducting materials (glass and zircon), metallic samples (steel and brass) and semiconductors (sulfides). The studies ...
The radionuclide characteristics of light-water-reactor (LWR) spent fuel play key roles in the design and licensing activities for radioactive waste transportation systems, interim storage facilities, and the final repository site. Several areas of analysis require detailed information concerning the time-dependent behavior of radioactive nuclides including (1) neutron/gamma-ray sources for shielding studies, (2) fissile/absorber concentrations for criticality safety determinations, (3) residual decay heat predictions for thermal considerations, and (4) curie and/or radiological toxicity levels for materials assumed to be released into the ground/environment after long periods of time. The crucial nature of the radionuclide predictions over both short and long periods of time has resulted in an increased emphasis on thorough validation for radionuclide generation/depletion codes. Current radionuclide generation/depletion codes have the capability to follow the evolution of some 1600 ...
Some hypo-stoichiometric Zr-based Laves phase alloys were prepared and studied from a viewpoint of discharge capacity for electrochemical application. After careful alloy design of ZrMn{sub 2}-based hydrogen storage alloys through changing their stoichiometry while substituting or adding some alloying elements, the Zr(Mn{sub 0.2}V{sub 0.2}Ni{sub 0.6}){sub 1.8} alloy reveals relatively good properties with regard to hydrogen storage capacity, hydrogen equilibrium pressure and electrochemical discharge capacity. In order to improve the discharge capacity and rate-capability, Zr is partially replaced by Ti. The discharge capacity of Zr{sub 1-x}Ti{sub x}(Mn{sub 0.2}V{sub 0.2}Ni{sub 0.6}){sub 1.8} (x=0.0, 0.2, 0.3, 0.4, 0.6) alloy electrodes at 30 C reaches a maximum value and decreases as the Ti fraction increases. In view of electrochemical and thermodynamic characteristics, the occurrence of a maximal phenomenon of the electrochemical discharge capacity of the alloy ...
An nonlinear analysis of an annular beam propagating through a cylindrical waveguide in the presence of a helical wiggler and an axial guide field is presented. The analysis is based upon the ARACHNE simulation which is a non-wiggler-averaged slow-time-scale simulation code in which the electromagnetic field is represented as a superposition of the TE and TM modes in a vacuum waveguide, and the beam space-charge waves are represented as a superposition of Gould-Trivelpiece modes. The DC self-electric and self-magnetic fields are also included in the model. ARACHNE has been extensively benchmarked against experiments at MIT and NRL in the past with good agreement, but all of these experiments have dealt with solid electron beams and beam voltages in excess of 200 kV. In seeking to reduce the beam voltage requirements we now consider the effect of operation with an annular beam. One advantage to be obtained by using an annular beam is that, for a fixed beam current, ...
We propose that a search for extra-terrestrial life can be approached as a Search for Extra-Terrestrial Homochirality{emdash}SETH. Homochirality is probably a pre-condition for life, so a chiral influence may be required to get life started. We explain how the weak force mediated by the {ital Z}{sup 0} boson gives rise to a small parity-violating energy difference (PVED) between enantiomers, and discuss how the resulting small excess of the more stable enantiomer may be amplified to homochirality. Titan and comets are good places to test for emerging pre-biotic homochirality, while on Mars there may be traces of homochirality as a relic of extinct life. Our calculations of the PVED show that the natural L-amino acids are indeed more stable than their enantiomers, as are several key D-sugars and right-hand helical DNA. Thiosubstituted DNA analogues show particularly large PVEDs. L-quartz is also more stable than D-quartz, and we believe that further crystal counts ...
Eukaryotic genomes encode a zinc finger protein (ZPR1) with tandem ZPR1 domains. In response to growth stimuli, ZPR1 assembles into complexes with eukaryotic translation elongation factor 1A (eEF1A) and the survival motor neurons protein. To gain insight into the structural mechanisms underlying the essential function of ZPR1 in diverse organisms, we determined the crystal structure of a ZPR1 domain tandem and characterized the interaction with eEF1A. The ZPR1 domain consists of an elongation initiation factor 2-like zinc finger and a double-stranded {beta} helix with a helical hairpin insertion. ZPR1 binds preferentially to GDP-bound eEF1A but does not directly influence the kinetics of nucleotide exchange or GTP hydrolysis. However, ZPR1 efficiently displaces the exchange factor eEF1B from preformed nucleotide-free complexes, suggesting that it may function as a negative regulator of eEF1A activation. Structure-based mutational and complementation analyses reveal ...
NMR spectroscopy combined with paramagnetic relaxation agents was used to study the positioning of the 40-residue Alzheimer Amyloid {beta}-peptide A{beta}(1-40) in SDS micelles. 5-Doxyl stearic acid incorporated into the micelle or Mn{sup 2+} ions in the aqueous solvent were used to determine the position of the peptide relative to the micelle geometry. In SDS solvent, the two {alpha}-helices induced in A{beta}(1-40), comprising residues 15-24, and 29-35, respectively, are surrounded by flexible unstructured regions. NMR signals from these unstructured regions are strongly attenuated in the presence of Mn{sup 2+} showing that these regions are positioned mostly outside the micelle. The central helix (residues 15-24) is significantly affected by 5-doxyl stearic acid however somewhat less for residues 16, 20, 22 and 23. This {alpha}-helix therefore resides in the SDS headgroup region with the face with residues 16, 20, 22 and 23 directed away from the hydrophobic ...
Full text: The aim of this study was to determine the accuracy of CT colonography (Virtual colonoscopy; VC) for polyp detection in a community-based screening program of asymptomatic subjects at average-risk of colorectal cancer (CRC). Average-risk subjects of two quintiles (50-54 and 65-69 years) were randomly selected from the electoral roll and invited to participate in a VC-based CRC screening program. After bowel preparation, bowel insufflation with CO_2 and intravenous hyoscine butylbromide (unless contra-indicated), supine and prone scans were acquired with a single array GE CTi helical scanner. Scanning parameters were: collimation 3 or 5mm; pitch 1.5:1 or 2.0:1; reconstructions at 1-2mm; 70mAs (5mm collimation) or 120mAs (3mm collimation). Subjects in whom VC demonstrated a polyp were offered colonoscopy (CY) on the same day. Participation rate in the study has been 25%.To date 176 subjects have undergone VC. 41 of 176 (23%) VCs were positive. CY detected ...
The purpose of this paper is to report the personal experience with helical CT evaluation of hepatocellular carcinoma treated with various percutaneous interventional procedures. From December 1996 to September 1998 it were examined with helical CT 41 patients (73 nodules in all) with hepatocellular carcinoma treated with percutaneous ablation therapies: conventional ethanol injection in 18 subjects (31 nodules), one-shot ethanol injection 3 (8 nodules), radiofrequency thermal ablation in 16 (25 nodules), and combined chemo embolization and ethanol injection in 4 (9 nodules). CT performed was 4-27 days after the last session, acquiring biphasic volumetric images in 14 patients and triphasic volumetric images in 27. A second treatment with subsequent CT study was performed for 28 lesions; 15 underwent 3 serial studies and 6 underwent 4 studies. Compared with pretreatment findings, the diameter was unchanged in 62% of the nodules and increased in ...
The main purpose of this work is to report the personal experience with addition of contrast-enhanced multiphase helical CT to unenhanced CT (Lipiodol CT) in the evaluation of patients with hepatocellular carcinoma treated with chemoembolization and to analyze the present role of oily agent CT. It has been retrospectively reviewed the examinations of 42 consecutive patients submitted to global chemoembolization over a 2-year period. CT was performed 18-30 days after the treatment. The Lipiodol CT study was carried out with volume acquisitions. It has been considered as nodules all well-defined areas with dense oily agent uptake; uptake itself was classified as: 0=absent, I=lower than 10% of the tumor volume; II=lower than 50%, III=50%, IV=homogeneous. Contrast-enhanced helical CT was performed with the 2-phase technique in 28 patients and with the 3-phase technique in 14; it has been considered as nodules all well-defined and relatively ...
In this report, I surveyed physics potential of the {gamma}{gamma} option of a linear e{sup +}e{sup -} collider with the following questions in mind: What new discovery can be expected at a {gamma}{gamma} collider in addition to what will be learned at its 'parent' e{sup +}e{sup -} linear collider? By taking account of the hard energy spectrum and polarization of colliding photons, produced by Compton back-scattering of laser light off incoming e{sup -} beams, we find that a {gamma}{gamma} collider is most powerful when new physics appears in the neutral spin-zero channel at an invariant mass below about 80% of the c.m. energy of the colliding e{sup -}e{sup -} system. If a light Higgs boson exists, its properties can be studied in detail, and if its heavier partners or a heavy Higgs boson exists in the above mass range, they may be discovered at a {gamma}{gamma} collider. CP property of the scalar sector can be explored in detail by making use of linear polarization ...
In this report, I surveyed physics potential of the #gamma##gamma# option of a linear e"+e"- collider with the following questions in mind: What new discovery can be expected at a #gamma##gamma# collider in addition to what will be learned at its 'parent' e"+e"- linear collider? By taking account of the hard energy spectrum and polarization of colliding photons, produced by Compton back-scattering of laser light off incoming e"- beams, we find that a #gamma##gamma# collider is most powerful when new physics appears in the neutral spin-zero channel at an invariant mass below about 80% of the c.m. energy of the colliding e"-e"- system. If a light Higgs boson exists, its properties can be studied in detail, and if its heavier partners or a heavy Higgs boson exists in the above mass range, they may be discovered at a #gamma##gamma# collider. CP property of the scalar sector can be explored in detail by making use of linear polarization of the colliding photons, decay angular correlations ...
Acanthamoeba castellanii myosins IA and IB demonstrate the catalytic properties of a myosin and can support analogues of contractile and motile activity in vitro, but their single, low molecular weight heavy chains, roughly globular shapes, and inabilities to self-assemble into filaments make them structurally atypical myosins. The authors present the complete amino acid sequence of the 128-kDa myosin IB heavy chain, which they deduced from the nucleotide sequence of the gene and which reveals that the polypeptide is a fusion of myosin-like and non-myosin-like sequences. Specifically, the amino-terminal approx. 76 kDa of amino acid sequence is highly similar to the globular head sequences of conventional myosins. By contrast, the remaining approx. 51 kDa of sequence shows no similarity to any portion of conventional myosin sequences, contains regions that are rich in glycine, proline, and alanine residues, and lacks the distinctive sequence characteristics of an ..cap ...
Acanthamoeba castellanii myosins IA and IB demonstrate the catalytic properties of a myosin and can support analogues of contractile and motile activity in vitro, but their single, low molecular weight heavy chains, roughly globular shapes, and inabilities to self-assemble into filaments make them structurally atypical myosins. The authors present the complete amino acid sequence of the 128-kDa myosin IB heavy chain, which they deduced from the nucleotide sequence of the gene and which reveals that the polypeptide is a fusion of myosin-like and non-myosin-like sequences. Specifically, the amino-terminal #approx# 76 kDa of amino acid sequence is highly similar to the globular head sequences of conventional myosins. By contrast, the remaining #approx# 51 kDa of sequence shows no similarity to any portion of conventional myosin sequences, contains regions that are rich in glycine, proline, and alanine residues, and lacks the distinctive sequence characteristics of an ...
We have constructed a Monte Carlo generator (the corresponding FORTRAN code can be obtained from the authors upon request) for lowest-order predictions for the processes {gamma}{gamma}{yields}4f and {gamma}{gamma}{yields}4f{gamma} in the standard model and extensions thereof by an effective {gamma}{gamma}H coupling as well as anomalous triple and quartic gauge-boson couplings. Polarization is fully supported, and a realistic photon beam spectrum can be taken into account. For the processes {gamma}{gamma}{yields}4f all helicity amplitudes are explicitly given in a compact form. The presented numerical results contain, in particular, a survey of cross sections for representative final states and their comparison to results obtained with the program package Whizard/Madgraph. The impact of a realistic beam spectrum on cross sections and distributions is illustrated. Moreover, the size of various contributions to cross sections, such as from weak charged- or ...
We have constructed a Monte Carlo generator (the corresponding FORTRAN code can be obtained from the authors upon request) for lowest-order predictions for the processes #gamma##gamma##->#4f and #gamma##gamma##->#4f#gamma# in the standard model and extensions thereof by an effective #gamma##gamma#H coupling as well as anomalous triple and quartic gauge-boson couplings. Polarization is fully supported, and a realistic photon beam spectrum can be taken into account. For the processes #gamma##gamma##->#4f all helicity amplitudes are explicitly given in a compact form. The presented numerical results contain, in particular, a survey of cross sections for representative final states and their comparison to results obtained with the program package Whizard/Madgraph. The impact of a realistic beam spectrum on cross sections and distributions is illustrated. Moreover, the size of various contributions to cross sections, such as from weak charged- or ...
Recent two major topics of Large Helical Device (LHD) towards fusion relevant conditions, high-density operation and high-ion-temperature operation, are reported. Super dense core plasma was obtained by the combination of repetitive hydrogen ice pellet injection and high power neutral beam injection (NBI) heating. A very peaked density profile with the highest central density of 1.1x1021 m-3 was produced showing that the particle transport was suppressed very well in the plasma core. The spatial density varies as the position of magnetic axis (Rax), and the steepest profile is obtained at Rax=3.95 m. The highest central ion temperature of 5.6 keV was obtained in hydrogen plasma at electron density of 1.6 x 1019 m-3 by NBI, where a peaked ion-temperature profile with internal ion energy transport barrier was observed. The profile of electron temperature did not change much and was broad even when the ion temperature had a peaked profile. The central ion temperature ...
In the future, the demand for energy is predicted to grow and more countries plan to utilize nuclear energy as their source of electric energy. This gives rise to many important issues connected to nuclear energy, such as finding methods that can verify that the spent nuclear fuel has been handled safely and used in ordinary power producing cycles as stated by the operators. Gamma ray spectroscopy is one method used for identification and verification of spent nuclear fuel. In the specific gamma ray spectroscopy method called gamma scanning the gamma radiation from the fission products Cs-137, Cs-134 and Eu-154 are measured in a spent fuel assembly. From the results, conclusions can be drawn about the fuels characteristics. This degree project examines the possibilities of using alternative measuring approaches when using the gamma scanning method. The focus is on examining how to increase the quality of the measured data. How to decrease the measuring time as compared with the present ...
In the future, the demand for energy is predicted to grow and more countries plan to utilize nuclear energy as their source of electric energy. This gives rise to many important issues connected to nuclear energy, such as finding methods that can verify that the spent nuclear fuel has been handled safely and used in ordinary power producing cycles as stated by the operators. Gamma ray spectroscopy is one method used for identification and verification of spent nuclear fuel. In the specific gamma ray spectroscopy method called gamma scanning the gamma radiation from the fission products Cs-137, Cs-134 and Eu-154 are measured in a spent fuel assembly. From the results, conclusions can be drawn about the fuels characteristics. This degree project examines the possibilities of using alternative measuring approaches when using the gamma scanning method. The focus is on examining how to increase the quality of the measured data. How to decrease the measuring time as compared with the present ...
Beach rocks are observed frequently on the tropical and subtropical sandy beaches where they express thin beds dipping seaward at less than 15 degrees. They consist of beach sediments including fossil shells, fragments of corals, diatoms and other biocarbonates, and are well cemented within the inter-tidal zone with calcium carbonate originated in sea water. Therefore, they are not only good indicators which show the past sea level, but also provide good sample material for radiocarbon dating. The locations of beach rocks give us an optimum condition studying a carbon cycle between land and marine environment by analyzing their isotope fractionations. In order to estimate the origin of calcium carbonate which worked as an adhesive when beach rocks were formed and to estimate the formative ages of beach rocks, a total of 330 fossil corals, fossil shells and calcarenite or calcirdite samples were collected from 128 sites of 16 islands consisting of the Nansei ...
A statistical pattern recognition method was applied to the analysis of the signals of crosssectional mean void fraction for discriminating gas-liquid two-phase flow regimes. The analysis and discrimination were carried out based on six key flow patterns : bubble, cap-bubble, plug, froth (F_I and F_I_I), and annular flow. For each flow condition 100 void signals with a recording dimension of 1 second were used and transferred to discrete data, the sampling frequency of which was selected at 100 Hz by comparison between correct recognition rates obtained from different frequencies. The magnitude of the time-averaged void fraction was partly employed supplementary to the pattern recognition method. The boundaries between the six flow regimes were determined corresponding to a correct recognition rate of 80 % and drawn on a superficial gas-liquid velocities diagram. These flow boundaries were also compared with those available in the literature. ...
Viscoelasticity of gel films prepared from solvent-soluble constituents without ash of coal using the mixed solvent of carbon disulfide and N-methyl-2-pyrrolidinone (CS2-NMP) was measured to study the network structure of the constituents. In experiment, Upper Freeport coal and Zao Zhuang coal were used as specimens. Viscoelasticity of various gels with different weight fractions of solvent was measured by creep measurement under a fixed load and stress-strain analysis under variable loads. In the 2nd and 3rd creep measurements, although no large changes in elastic strain and viscoelastic strain were found, viscous strain gradually decreased with an increase in viscosity. In the case of small weight fraction of solvent, small viscous strain and viscoelastic strain were found, while slightly large elastic strain was found. It was thus suggested that this elastic strain is derived from not only physical cross-linked networks by coal-solvent ...
The two-phase flow regime transition in a large diameter (I.D.=200mm) vertical pipe was experimentally investigated using a dual-sensor optical probe. The flow transitions from bubbly to chum without an intermediate slug flow regime as the air flow rate is increased. The transition boundaries developed for bubbly to slug flow in small diameter pipes are compared to the bubbly to chum flow transition of the present experiment. The bubbly to chum transition occurs at a void fraction of about 0.15 compared to 0.25 for bubbly to slug transition in small diameter pipes. The radial distribution of bubble diameter, bubble frequency, bubble velocity and local void fraction were obtained using a dual-sensor optical probe at different flow conditions. The Probability Density Function (PDF) and Cumulative Distribution Function (CDF) of the bubble velocity and size are used to study the flow regime transition in the large diameter pipe. (author)
The two-phase flow regime transition in a large diameter (I.D.=200mm) vertical pipe was experimentally investigated using a dual-sensor optical probe. The flow transitions from bubbly to chum without an intermediate slug flow regime as the air flow rate is increased. The transition boundaries developed for bubbly to slug flow in small diameter pipes are compared to the bubbly to chum flow transition of the present experiment. The bubbly to chum transition occurs at a void fraction of about 0.15 compared to 0.25 for bubbly to slug transition in small diameter pipes. The radial distribution of bubble diameter, bubble frequency, bubble velocity and local void fraction were obtained using a dual-sensor optical probe at different flow conditions. The Probability Density Function (PDF) and Cumulative Distribution Function (CDF) of the bubble velocity and size are used to study the flow regime transition in the large diameter pipe. (author)
Thermal conductivity is an important property that governs the behaviour of leaf compost biofilters used in treating gaseous pollutants. Measurements were carried out for the thermal conductivity (K) of 44 samples of leaf compost, covering wide ranges of the volume fractions of water (#xi#_w), solids (#xi#_s) and air (#xi#_a), at 20 deg. C using an unsteady state thermal probe. The results indicated that the compost thermal conductivity increased with an increase in #xi#_w, with a decrease in #xi#_a, and with an increase in the degree of saturation (defined as the volumetric fraction of water in the total void space). The predictions from the Woodside-Messmer quadratic parallel (QP) model for the thermal conductivity of leaf compost were higher than the experimental values. A simple linear relationship was developed between the thermal conductivity and the degree of saturation, which provided a satisfactory correlation for the data measured in ...
The relative contributions of interstitials and vacancies to diffusion of a dopant A in silicon are specified by the interstitial fraction of diffusivity, f{sub A}. Accurate knowledge of f{sub A} is required for predictive simulations of Si processing during which the point defect population is perturbed, such as transient enhanced diffusion. While experimental determination of f{sub A} is traditionally based on an underdetermined system of equations, we show here that it is actually possible to derive expressions that give meaningful bounds on f{sub A} without any further assumptions but that of local equilibrium. By employing a pair of dopants under the same point-defect perturbance, and by utilizing perturbances very far from equilibrium, we obtain experimentally f{sub Sb}{le}0.012 and f{sub B}{ge}0.98 at temperatures of {approximately}800{degree}C, which are the strictest bounds reported to date. Our results are in agreement with a theoretical expectation that ...
The relative contributions of interstitials and vacancies to diffusion of a dopant A in silicon are specified by the interstitial fraction of diffusivity, f_A. Accurate knowledge of f_A is required for predictive simulations of Si processing during which the point defect population is perturbed, such as transient enhanced diffusion. While experimental determination of f_A is traditionally based on an underdetermined system of equations, we show here that it is actually possible to derive expressions that give meaningful bounds on f_A without any further assumptions but that of local equilibrium. By employing a pair of dopants under the same point-defect perturbance, and by utilizing perturbances very far from equilibrium, we obtain experimentally f_S_b#<=#0.012 and f_B#>=#0.98 at temperatures of #approx#800 degree C, which are the strictest bounds reported to date. Our results are in agreement with a theoretical expectation that a substitutional dopant in Si ...
Purpose: To report outcomes of a single institution study of stereotactic body radiotherapy (SBRT) for unresectable cholangiocarcinoma. The dose-volume dependency of the observed gastrointestinal toxicity is explored. Methods and materials: Twenty-seven patients with unresectable cholangiocarcinoma (n = 26 Klatskin tumours and one intrahepatic cholangiocarcinoma (IHCC)) were treated by linac-based SBRT. The dose schedule was 45 Gy in three fractions prescribed to the isocenter. Results: The median progression-free survival and overall survival were 6.7 and 10.6 months, respectively. With a median follow-up of 5.4 years, 6 patients had severe duodenal/pyloric ulceration and 3 patients developed duodenal stenosis. Duodenal radiation exposure was higher in patients developing moderate to high-grade gastrointestinal toxicity with the difference in mean maximum dose to 1 cm"3 of duodenum reaching statistical significance. A statistically significant association between ...
Sodium nitrate waste has been successfully solidified in two types of polymeric materials: polyethylene, a thermoplastic material, and polyester styrene (PES), a thermosetting material. Waste form property evaluation tests such as ANS 16.1 leaching test and compressive strength measurements were performed on the waste forms containing various amounts of sodium nitrate. A single-screw extruder was employed for incorporating dry waste into polyethylene at its melt temperature of 120/sup 0/C to produce a homogenous mixture. Results of the leaching test for polyethylene waste forms containing 30, 50, 60 and 70 wt% sodium nitrate are presented as cumulative fraction leached and leaching indices ranging from 11 to 7.8. Two PES systems are discussed. The first is for solidification of dry salt wastes and the second is a water extendible system that is compatible with wet waste streams. Leaching data for PES and water extendible PES waste forms containing 30 wt% sodium ...
Both x-ray and optical cone-beam CT (CBCT) scanners are limited by scattered photons that contaminate the primary images. Transparent radiochromic gels and plastics are anticipated to produce less scattering than polymerization gels and hence result in reconstructed dose distributions with greater contrast and dynamic range. Four methods of scatter measurement were investigated to quantify scatter fractions using an in-house optical CBCT scanner. The methods consisted of generating either 'coin' shadows or primary beamlets in transmission images. The four methods generated similar results of 10% scatter fractions in gel transmission images for this particular scanner configuration with both leuco crystal violet and carbon black micelle gels. The scatter contributions were distributed as 5% from micelle gel, 2% from Teflon wall, 2% from refractive index matching liquid and 1% other sources. Applying a uniform background ...
Three dispersants (stearic acid, oleic acid, and poly-(12-hydroxystearic acid)) are compared for their ability to produce low-viscosity suspensions of zirconia in kerosene. Rheological measurements and sediment packing density measurements show that poly(12-hydroxystearic acid) is a better dispersant than stearic acid or oleic acid; this is explained in terms of the longer tail of the poly-(12-hydroxystearic acid) surfactant molecule. The amount of dispersant can be optimized to reduce viscosity and yield point of the suspension, and to eliminate thixotropic hysteresis. The use of a dispersion medium of lower viscosity than the dispersant makes it easy to detect when complete monolayer coverage has been achieved. The loss of pseudoplasticity, brought about by a higher degree of deflocculation, can be recovered by increasing the volume fraction of solids of a suspension and this is beneficial in the plastic forming of ceramics. Rheological measurements showed that ...
We review the progress on experimental studies of the non-$D\\bar D$ decays of the $\\psi(3770)$ resonance. With the world average of the observed cross sections for $D\\bar D$ production measured at 3.773 GeV by the MARK-I, MARK-II, BES and CLEO Collaborations, combined together with the cross section for $\\psi(3770)$ production at its peak as well as initial state radiative correction factor, we find that the non-$D\\bar D$ branching fraction of $\\psi(3770)$ decays is $B[\\psi(3770)\\to {\\rm non}-D\\bar D]=(19.8\\pm 1.8 \\pm 5.6)%$, which is consistent within error with $B[\\psi(3770)\\to {\\rm non}-D\\bar D]=(14.7\\pm 3.2)%$ measured previously by the BES Collaboration. In addition, a global amplitude analysis of the cross sections for $e^+e^- \\to {\\rm LH}$ (LH= light hadron) measured by the CLEO Collaboration shows that the light hadron branching fraction of $\\psi(3770)$ decays can be as large as about 11%. Combing the totally ...
By improving the currently used lactoperoxidase method, we were able to obtain radioiodinated chicken luteinizing hormone (LH) that shows high specific binding and low nonspecific binding to a crude plasma membrane fraction of testicular cells of the domestic fowl and the Japanese quail, and to the ovarian granulosa cells of the Japanese quail. The change we made from the original method consisted of (1) using chicken LH for radioiodination that was not only highly purified but also retained a high receptor binding potency; (2) controlling the level of incorporation of radioiodine into chicken LH molecules by employing a short reaction time and low temperature; and (3) fractionating radioiodinated chicken LH further by gel filtration using high-performance liquid chromatography. Specific radioactivity of the final {sup 125}I-labeled chicken LH preparation was 14 microCi/micrograms. When specific binding was 12-16%, nonspecific binding was as ...
A comprehensive experimental program on pullout tests of steel fibers from cement based matrices is described. A specially designed single fiber pullout apparatus was used to provide a quantitative determination of interfacial properties that are relevant to toughening brittle materials through fiber reinforcement. The parameters investigated included a specially designed high strength cement based matrix called Densified Small Particles system (DSP), a conventional mortar matrix, fiber embedment length, and the fiber volume fraction. The mediums from which the fiber was pulled included a control mortar mix without fibers, a mortar mix with 3, and 6 percent fibers by volume. The results indicate that: (1) the dense DSP matrix has significantly improved interfacial properties as compared to the conventional mortar matrix. (2) Increasing the fiber embedment length and the fiber volume fraction in the cement matrix increase the peak pullout load ...
Cell extracts of the thermophile Clostridium thermohydrosulfuricum catalyzed the phosphorylation by (..gamma..-/sup 32/P)ATP of several endogenous proteins with M/sub r/s between 13,000 and 100,000. Serine and tyrosine were the main acceptors. Distinct substrate proteins were found in the soluble (e.g., proteins p66, p63, and p53 of M/sub r/s 66,000, 63,000, and 53,000, respectively) and particulate (p76 and p30) fractions, both of which contained protein kinase and phosphatase activity. The soluble fraction suppressed the phosphorylation of particulate proteins and contained a protein kinase inhibitor. Phosphorylation of p53 was promoted by 10..mu..M fructose 1,6-bisphosphate or glucose 1,6-bisphosphate and suppressed by hexose monophosphates, whereas p30 and p13 were suppressed by 5 ..mu..M brain (but not spinach) calmodulin. Polyamines, including the odd polyamines characteristic of thermophiles, modulated the labeling of most of the ...
This specialist meeting on Advanced Instrumentation and Measurements Techniques was held in Santa Barbara (USA) in 1997 and attracted some 70 participants in ten technical sessions and a session of the round table discussions, with a total of 41 papers. It was intended to bring together the international experts in multi-phase flow instrumentation, experiment and modeling to review the state-of-the-art of the two-phase flow instrumentation methods and to discuss the relation between modeling needs and instrumentation capabilities. The following topics were included: Modeling needs and future direction for improved constitutive relations, interfacial area transport equation, and multi-dimensional two-fluid model formulation; local instrumentation developments for void fraction, interfacial area, phase velocities, turbulence, entrainment, particle size, thermal non-equilibrium, shear stress, nucleation, condensation and boiling; global instrumentation developments ...
The crystallization dynamics of Nylon 66/Nylon 48 blends, the crystalline/crystalline polymer blend, was analyzed by differential scanning calorimetry (DSC) under isothermal conditions. The equilibrium melting temperature (T{sub m}{sup 0}), crystal growth rate (G) and the nucleation rate (N) depended on both the degree of supercooling ({delta}T) and the blend fraction (phi). The {delta}T/T{sub m}{sup 0} values obtained at the fixed G, which corresponded to the chemical potential different between molecules in the liquid and the crystal states, and the surface free energy parameters evaluated from G and N depended on phi for blends. The results suggested that Nylon 66/Nylon 48 blends are miscible in all blend fractions. The result agrees with the intermolecular interaction parameter ({chi}) obtained from T{sub m}{sup 0} depression. Infrared spectroscopic and X-ray diffraction data indicated that the hydrogen bond became weak and the crystalline ...
Piezoelectric ceramics for acoustic applications have been prepared by mixing the piezoelectric phase Pb{sub 1-1.5x}La{sub x}{open_square}{sub x/2}(Ti{sub 1-y}Zr{sub y})O{sub 3} (PLZT) with variable fractions of Al{sub 2}O{sub 3}. The samples are in form of pellets and polarized at high temperature. After thermal treatment, X-ray diffraction and scanning electron microscopy have been used to determine the phase and morphological modifications. The morphotropic PLZT initial phase disproportionates into modified PLZT and ZrO{sub 2} phases. Using electrical impedance spectroscopy, the resonance frequencies of the composite system have been determined and analyzed. As the Al{sub 2}O{sub 3} volume fractions increase, the resonance frequency and the amplitude of the electrical response both decrease. An interpretation of the role of Al{sub 2}O{sub 3} additions is proposed in terms of phase and microstructure modifications. Using LRC electrical ...
Powders with nominal compositions (in atomic percent) Ti-48Al and Ti-48Al-2Nb-2Cr were prepared by the plasma rotating electrode process (PREP) and gas atomization (GA) techniques. As-solidified and heat-treated (1000degC per 3 h) powder samples were examined by metallography, scanning electron microscopy, X-ray diffraction and transmission electron microscopy. The microstructures of the powders were characterized as a function of atomization technique, alloy content, powder particle size (solidification rate) and thermal history. All of the as-solidified powders were comprised of disordered [alpha], and ordered [alpha][sub 2]-Ti[sub 3]Al and [gamma]-TiAl. For both alloys, a larger volume fraction of [alpha] and [alpha][sub 2] was observed in the PREP powders relative to GA powders of comparable size. Additionally, for both alloys and both atomization techniques, the volume fraction of [alpha][sub 2] was observed to increase with decreasing ...
Meltdown and gasification of waste in an oxygen atmosphere ('2sv' process) is an economically efficient alternative to energetic and thermal utilisation of biomass. Organic pollutants are split at temperatures up to 2000 C in a reducing atmosphere. The process uses elements of the oxygen cupola furnace for melting and gasification of many different waste fractions, e.g. polluted waste wood, household refuse and bulk waste, old tyres, light shredder fractions, sewage sludge, etc. [German] Die Sauerstoff-Schmelz-Vergasung ('2sv') stellt eine wirtschaftliche Alternative zur energetischen Nutzung von Biomassen wie auch zur thermischen Abfallverwertung dar. Organische Schadstoffe werden bei diesem neuen Verfahren bei Temperaturen bis zu 2000 C unter reduzierenden Bedingungen aufgespalten. Das Verfahren nutzt Elemente des Sauerstoff-Kupolofens fuer die Schmelzvergasung und eignet sich fuer zahlreiche Abfallarten ...
The decay modes $\\jpsi\\ar\\gamma\\pi^0, \\gamma\\eta$ and $\\gamma\\etap$ are analyzed using a data sample of 58 million $\\jpsi$ decays collected with the BESII detector at BEPC. The branching fractions are determined to be: $Br(\\jpsi\\ar\\gamma\\pi^0)=(3.13^{+0.65}_{-0.44})\\times10^{-5}$, $Br(\\jpsi\\ar\\gamma\\eta)=(11.23\\pm0.89)\\times10^{-4}$, and $Br(\\jpsi\\ar\\gamma\\etap)=(5.55\\pm0.44)\\times10^{-3}$, where the errors are combined statistical and systematic errors. The ratio of partial widths $\\Gamma(\\jpsi\\ar\\gamma\\etap)/\\Gamma(\\jpsi\\ar\\gamma\\eta)$ is measured to be $4.94\\pm0.40$, and the singlet-octet pseudoscalar mixing angle of $\\eta-\\etap$ system is determined to be $\\theta_{P}=(-22.08\\pm0.81)^{\\circ}$.
Using 14M psi(2S) events taken with the BES-II detector, chi_cJ-->K+K-K+K- decays are studied. For the four-kaon final state, the branching fractions are B(chi_c0,1,2 -->K+K-K+K-)=(3.47\\pm 0.22\\pm 0.48)\\times 10^{-3}, (0.68\\pm 0.13\\pm 0.10)\\times 10^{-3}, and (1.88\\pm 0.18\\pm 0.28)\\times 10^{-3}. For the \\phi K+K- final state, the branching fractions, which are measured for the first time, are B(chi_c0,1,2-->\\phi K+K-)=(1.02\\pm 0.22\\pm 0.15)\\times 10^{-3}, (0.44\\pm 0.14\\pm 0.07)\\times 10^{-3}, and (1.46\\pm 0.21\\pm 0.22)\\times 10^{-4}. For the \\phi\\phi final state, B(chi_{c0,2}-->\\phi\\phi)=(0.94\\pm 0.21\\pm 0.14)\\times 10^{-3} and (1.48\\pm 0.26\\pm 0.23)\\times 10^{-3}.
The objective of this work is the measurement of two-phase flow parameters to support development of constitutive relationships for the HANARO/MAPLE type finned fuel using Real-Time Neutron Radiography (RTNR). A single element finned Fuel Element Simulator was used with R134a Freon flow. To observe the effect of a spacer device on void distribution, single pin tests were performed with and without a spacer. By analyzing the RTNR images using image processing, the effects of the spacer on the time-averaged and instantaneous void fraction distributions were studied. For the experimental results without a spacer, the time-averaged local void distribution is radially asymmetric and the degree of void fluctuation increases with a decreasing frequency along the heated channel, where the observed asymmetry may be caused by flow induced vibration. For the experimental results with a spacer, the spacer clearly limits any significant vibration and the local void distribution ...
The objective of this work is the measurement of two-phase flow parameters to support development of constitutive relationships for the HANARO/MAPLE type finned fuel using Real-Time Neutron Radiography (RTNR). A single element finned Fuel Element Simulator was used with R134a Freon flow. To observe the effect of a spacer device on void distribution, single pin tests were performed with and without a spacer. By analyzing the RTNR images using image processing, the effects of the spacer on the time-averaged and instantaneous void fraction distributions were studied. For the experimental results without a spacer, the time-averaged local void distribution is radially asymmetric and the degree of void fluctuation increases with a decreasing frequency along the heated channel, where the observed asymmetry may be caused by flow induced vibration. For the experimental results with a spacer, the spacer clearly limits any significant vibration and the local void distribution ...
Of the many ways of detecting high redshift galaxies, the selection of objects due to their redshifted Ly-alpha emission has become one of the most successful. But what types of galaxies are selected in this way? Until recently, Ly-alpha emitters were understood to be small star-forming galaxies, possible building-blocks of larger galaxies. But with increased number of observations of Ly-alpha emitters at lower redshifts, a new picture emerges. Ly-alpha emitters display strong evolution in their properties from higher to lower redshift. It has previously been shown that the fraction of ultra-luminous infrared galaxies (ULIRGs) among the Ly-alpha emitters increases dramatically between redshift three and two. Here, the fraction of AGN among the LAEs is shown to follow a similar evolutionary path. We argue that Ly-alpha emitters are not a homogeneous class of objects, and that the objects selected with this method reflect the general star forming ...
The present review focuses on the isotropic composition in extra-terrestrial materials. There are many different factors in the variation in isotopic abundance between terrestrial and extra-terrestrial materials. Major factors in unusual isotopic composition are roughly grouped into three categories: factors associated with fractionation of isotopes, nuclear reaction or radioactive disintegration. Fractionation takes place due to differences in mass among various isotopes. There are physical and chemical factors. Physical ones include vaporization and condensation which meteorites may experience during their formation while the chemical ones include chemical reactions and chemical equilibration. There phenomena are mentioned as factors in the variation in isotopic ratio which is associated with nuclear reactions. An important nuclear reaction is the formation of elements that has been occurring continuously in stars since the big bang. The ...
We investigate the possibility of producing the $\\omega\\phi$ threshold enhancement recently observed in the $J\\psi\\to\\gamma X(1812),~X(1812)\\to\\omega\\phi$ at BES by assuming the X(1812) to be a candidate of $(K^{*}\\bar K^{*0})$ molecular state. We evaluate the decay rate of $X(1812)\\to\\eta\\eta', \\eta\\eta, \\omega\\phi, K^+K^-, \\rho^+\\rho^-$, $\\omega\\omega, K^{*+}K^{*-}$ and $\\pi^+\\pi^-$ based on the X(1812) to be a candidate of $(\\ksks)$ molecule. It turns out the X(1812) dominantly decays into $\\eta\\eta'$ and $\\eta\\eta$. These channels are suggested to be the laboratory to test the molecular scenario in experiment. We also evaluate the branching fraction $Br(X\\to\\omega\\phi)\\simeq 4.60%$. However, the X(1812) has small branching fractions to decay into other $VV$ or $PP$ final states, from which it seems to be consistent with the experimental observation. In the molecular scenario, the X(1812) production rate is ...
Gel filtration of human erythrocyte (RBC) lysate incubated with labeled thyroxine (Tu) or triiodothyronine (Tt) revealed co-elution of a major iodothyronine-binding fraction (R-2) and hemoglobin. Solutions of purified human hemoglobin and Tt also showed co-elution of hormone and hemoglobin. Because hematin and protoporphyrin were shown to bind labeled Tt, the oxygen-binding site on hemoglobin was excluded as the site of iodothyronine-hemoglobin interaction. Analysis of hormone binding by heme and globin moieties showed Tt binding to be limited to the heme fraction. Addition of excess unlabeled Tt to hemoglobin or heme incubated with labeled Tt indicated 75% to 90% of hormone binding was poorly dissociable. These observations suggested that the presence of hemoglobin in RBC lysate or in serum could influence the measurement of Tu and Tt by specific radioimmunoassay (RIA). Subsequent studies of the addition to serum of human hemoglobin revealed a ...
For developing coal liquefaction processes, it is an important problem to improve the light oil yield with increased oil yield. It was previously reported that distillate mainly containing lighter fraction can be produced with high oil yield by reducing the iron/sulfur catalyst addition in slurry, by recycling gas in the process operation, by utilizing these effects, and by using heavy oil as recycling solvent. In this study, the maximum distillate yield of Victorian brown coal was investigated through continuous liquefaction using a bench scale unit. In addition, operation conditions for obtaining sufficient oil yield were investigated under the reduced catalyst addition into one-third. Consequently, it was confirmed that the maximum content of lighter fraction in distillate product was obtained with reduced catalyst addition by using heavy oil as recycling solvent, by adopting new catalyst, and by utilizing effects of CLB recycling and gas ...
Hybrid density functionals, which replaces a fraction of a density functional theory exchange with exact Hartree-Fock (HF) exchange, have been used to study the structural, magnetic, and electronic properties of ?-Pu. The fractions of exact Hartree-Fock exchange used were 25%, 40%, and 55%. Compared to the pure PBE functional, the lattice constants expanded with respect to the experimental value when the PBE-HF hybrid functionals were applied. For pure PBE and hybrids functionals with HF exchange amounts of 25% and 40%, the ground state structure was anti-ferromagnetic, while for 55% HF contribution the ground state was non-magnetic. The 5f electrons tend to exhibit slight delocalization or itinerancy for the pure PBE functional and well-defined localization for the hybrid functionals, with the degree of 5f electron localization increasing with the amount of HF exchange. Overall, the performance of the hybrid density functionals do not seem ...
Electron interference in the presence of nonclassical microwaves with frequency {omega}{sub 1} and classical RF radiation with frequency {omega}{sub 2}, is studied. The relative phase factor between the two electron beams is a quantum-mechanical operator, whose expectation value with regard to the density matrix describing the nonclassical microwaves, determines the interference. It is shown that the visibility of the time-averaged intensity is a constant for all irrational values of {omega}{sub 1}/{omega}{sub 2}, and shows peaks (fractional Shapiro steps) at all rational values. These peaks can provide direct experimental evidence of the highly nonlinear processes of frequency conversion from {ital N} photons with frequency {omega}{sub 1}, to {ital M} photons with frequency {omega}{sub 2}. Results for various types of nonclassical microwaves (e.g., coherent states, squeezed states, number eigenstates, etc.) are derived and a comparison with the corresponding ...
The measurement of two-phase flow parameters and development of constitutive relationships for the HANARO/MAPLE type finned fuel using Real-Time Neutron Radiography (RTNR) is discussed in this paper. A single element finned Fuel Element Simulator (FES) was used with R134a Freon as the working fluid. To observe the effect of a spacer device on void distribution, single pin tests were performed with and without a spacer. By analyzing the RTNR images using image processing, the effects of the spacer on the time-averaged and instantaneous void fraction distribution were studied. For the experimental results without a spacer, the time-averaged local void distribution is radially asymmetric and the degree of void fluctuation increases with a decreasing frequency along the heated channel, where the observed asymmetry may be caused by flow induced vibration. For the experimental results with a spacer, the spacer clearly limits any significant vibration and the local void ...
The measurement of two-phase flow parameters for development of constitutive relationships for the HANARO/MAPLE type finned fuel using Real-Time Neutron Radiography (RTNR) is discussed in this paper. A single element finned Fuel Element Simulator (FES) was used with Freon 134a as the working fluid. To observe the effect of a spacer device on void distribution, single pin tests were performed with and without a spacer present. By analyzing the RTNR images using image processing, the effects of the spacer on the time-averaged and instantaneous void fraction distribution were studied. For the experimental results without a spacer, the time-averaged local void distribution is radially asymmetric and the degree of void fluctuation increases with a decreasing frequency along the heated channel, where the observed asymmetry may be caused by flow induced vibration. For the experimental results with a spacer, the spacer clearly limits any significant vibration and the local ...
Use of high plutonia MOX as fuel is contemplated from the point of view of rapid disposition of plutonium and economic power generation. The fuel pellets are subjected to steep thermal gradients #approx# 1700 K drop across a radius of #approx# 2.5mm. This leads to evaporation-condensation of the fuel constituents to cooler regions. Vaporization depends on fuel compositions such as Pu fraction, Oxygen-to-Metal (O/M) ratio and local temperature. Knowledge of vapour chemistry is essential in understanding the fuel behavior. The vaporization behaviour of MOX was analyzed in this work using thermochemical methods. The vapour phase consisted of nine species; O, O_2, Pu, PuO, PuO_2, U, UO, UO_2 and UO_3. Oxygen formed part of the vapour phase along with other species and oxygen potential was not controlled independently. The vapour pressures were estimated at 2000 K as a function of (O/M) for several Pu-fraction. Results for MOX-28%PuO_2 is shown in ...
This report describes results from emissions testing of a prototype diesel engine, developed by Volvo Truck Corporation of Sweden, which uses pilot injection of diesel fuel for compression ignition of alcohol fuel injection for main combustion. In addition to this dual-fuel engine, emission testing was also conducted on a heavy-duty diesel engine of similar design. Both engines were tested over the 1979 13-mode FTP, or shorter versions of this modal test, and over the 1984 Transient FTP as well as an experimental bus cycle. The dual-fuel engine was characterized with methanol, ethanol and ethanol with 30 percent water (wt %). An oxidation catalyst was also used with methanol and ethanol. Emission characterization included regulated emissions (HC, CO, and NOX) along with total particulate, unburned alcohols, individual hydrocarbons, aldehydes, phenols, and odor. The particulate matter was characterized in terms of particle size distribution, sulfate content, C, H, S, metal content, and ...
This work is a retrospective study of 86 patients with squamous cell (51) and basal cell (35) carcinoma of the face. The median age was 67 years. The staging is as following: 31 cases T{sub 1} and T{sub 2}, 55 patients T{sub 3} and T{sub 4}. All patients were considered NO. Electron beam was used in all cases and energy ranged from 5 to 15 MeV depending on the thickness of the tumor. The total tumor dose was 60-70 Gy delivered in 6 weeks. In 7 cases of very old patients the authors have used concentrated irradiation: 3 patients received 21 Gy in one fraction and 4 patients 48 Gy in 8 fractions. 96.8% patients T{sub 1} i T{sub 2} are NED contrary to 56.4% T{sub 3} i T{sub 4}. Cosmetic results were considered as good in 52, fairly good in 7 and bad in 2 patients.
An experimental investigation was conducted to evaluate the effect of three different oxygenated compounds, diglyme, diethyl maleate and dibutyl maleate, on emissions from a Volkswagen 1.9 litre, turbocharged, direct injection diesel engine. Sampling was performed using a mini-dilution tunnel technique to obtain particulate matter and a Fourier transform infrared (FTIR) spectrometer for gaseous emissions. The particulate samples were analysed using thermal analysis and Soxhlet extraction to determine the fraction of volatile and soluble organic material respectively. All three oxygenated compounds were found to be effective at reducing particulate emissions, with the maleate compounds being more effective overall than the diglyme. Analysis of the relative contributions of changes in the soot and soluble organic fraction (SOF) to the reduction of particulate matter indicated that, for diethyl maleate and diglyme, reductions in soot were the ...
Clove (Caryophyllus aromaticus L.) has been used for clinical procedures. Blood constituents labeled with technetium-99m (99mTc) are used in nuclear medicine. The aim of this work was to evaluate the effects of clove extract on the labeling blood constituents with 99mTc and on the morphology of red blood cells. Blood samples were incubated with clove, stannous chloride and 99mTc. Plasma, blood cells, insoluble fractions of plasma and blood cells were separated. The radioactivity was counted and percentage of radioactivity (%ATI) to each blood fraction was calculated. The shape and morphometric parameter (perimeter/area ratio) were evaluated. Clove extract altered significantly (p<0.05) the %ATI of blood constituents and the shape of red blood cells without modifying the perimeter/area ratio. The results indicate that clove extract presents chemical compounds that interfere with the radiolabeling of blood constituents and alter the ...
Hybrid density functionals, which replace a fraction of density functional theory (DFT) exchange with exact Hartree-Fock (HF) exchange, have been used to study the structural, magnetic, and electronic properties of ?-Pu. The fractions of exact Hartree-Fock exchange used were 25%, 40%, and 55%. Compared to the pure PBE functional, the lattice constants expanded with respect to the experimental value when the PBE-HF hybrid functionals were applied. For pure PBE and hybrid functionals with HF exchanges amounts of 25% and 40%, the ground state structure was anti-ferromagnetic, while for 55% HF contribution the ground state was non-magnetic. The 5f electrons tend to exhibit slight delocalization or itinerancy for the pure PBE functional and well-defined localization for the hybrid functionals, with the degree of 5f electron localization increasing with the amount of HF exchange. Overall, the performance of the hybrid density functionals does not ...
Hybrid density functionals, which replace a fraction of density functional theory (DFT) exchange with exact Hartree-Fock (HF) exchange, have been used to study the structural, magnetic, and electronic properties of #delta#-Pu. The fraction of exact Hartree-Fock exchange used were 25%, 40%, and 55%. Compared to the pure PBE functional, the lattice constants expanded with respect to the experimental value when the PBE-HF hybrid functionals were applied. For pure PBE and hybrid functionals with HF exchanges amounts of 25% and 40%, the ground state structure was anti-ferromagnetic, while for 55% HF contribution the ground state was non-magnetic. The 5f electrons tend to exhibit slight delocalization of itinerancy for the pure PBE functional and well-defined localization for the hybrid functionals, with the degree of 5f electron localization increasing with the amount of HF exchange. Overall, the performance of the hybrid density functionals does ...
Inert gas contamination, structure and mechanical properties of consolidated high-Ni alloy powder material were studied to improve its characteristics. In experiment, the chemical composition and fraction of porosity in cross sections of Alloy 625 powder were examined which was produced by Ar gas atomization method impinging supplemental gas jet onto accumulated alloy powder in the bottom of a tank for rapid cooling. The structure and mechanical properties of the alloy rod were also examined which was produced by hot hydrostatic pressing or hot extrusion of the powder filled into a capsule. As a result, although Ar content included in the powder produced by Ar gas atomization method decreased with reduction in grain size, the fine powder less than 22{mu}m still included Ar of nearly 0.5mass-ppm. Obvious correlation was found between the fraction of porosity in powder cross sections and Ar in the powder. Although cavities were detected in the ...
The two-phase annular regime is characterized by a high velocity gas stream flowing through the core of the tube surrounded by a thin, highly agitated liquid film flowing concurrently along the tube wall. Part of the liquid may be entrained as droplets in the gas phase. The specific goals of this study were to measure fully developed rates of interchange and entrained fraction over a wide range of flow variables in the upward configuration of the annular regime, to obtain a more fundamental understanding of liquid interchange phenomena via studies of liquid film characteristics and to develop an improved design correlation for the entrained fraction. Towards this end, air-water experiments were conducted in two vertical pipe lines, 2.54 and 4.20 cm in diameter. Air velocities ranging from 20 to 120 m/s and total liquid flow rates ranging from 10 to 100 g/s were investigated. Two models for the rate of atomization, proposed by Tatterson (1975) ...
Pyrolysis of Greek fir wood samples in a fluidized bed reactor was studied. The experimental conditions selected control the yield of gaseous, liquid and solid products. The factors examined were: pyrolysis temperature, mean particle size, pressure, residence time of volatiles, lignin content of biomass and moisture content. The experiments were performed on the basis of a 12-run Plackett-Burman fractional factorial design. Statistical analysis of the data showed that the pyrolysis temperature is the main factor affecting the distribution of the yields of liquids, their phenolic fraction and gases in the range of experimental conditions tested. Empirical expressions were obtained from linear regression giving the yields of liquids, phenols and gases in terms of temperature. The maximum predicted yields were 56 and 12 wt.% on a moisture-free basis at 520 C and 545 C for liquids and phenols, respectively. The yield of gases increased ...
We describe a method for affinity purification of sequence-specific DNA binding proteins that is fast and effective. Complementary chemically synthesized oligodeoxynucleotides that contain a recognition site for a sequence-specific DNA binding protein are annealed and ligated to give oligomers. This DNA is then covalently coupled to Sepharose CL-2B with cyanogen bromide to yield the affinity resin. A partially purified protein fraction is combined with competitor DNA and subsequently passed through the DNA-Sepharose resin. The desired sequence-specific DNA binding protein is purified because it preferentially binds to the recognition sites in the affinity resin rather than to the nonspecific competitor DNA in solution. For example, a protein fraction that is enriched for transcription factor Sp1 can be further purified 500- to 1000-fold by two sequential affinity chromatography steps to give Sp1 of an estimated 90% homogeneity with 30% yield. ...
This thesis consists of an introduction and five included papers. Of these, four papers are published in international journals and the fifth was submitted for review in April 2000. Emphasis has been placed on both naturally and artificially generated light hydrocarbons in petroleum fluids and their proposed source rocks as well as direct application of light hydrocarbons to oil/source rock correlations. Collectively, these papers describe a strategy for interpreting the source of the light hydrocarbons in original oils and condensates as well as the source of the asphaltene fractions from the reservoir fluids. The influence of maturity on light hydrocarbon composition has also been evaluated. The papers include (1) compositional data on the light hydrocarbons from thermal extracts and kerogen pyrolysates of sediment samples, (2) light hydrocarbon data of oils and condensates as well as the pyrolysis products of the asphaltenes from these fluids, (3) assessment of ...
An analytical study of the ice-formation process associated with heat-conducting plates located perpendicularly to isothermally heated and cooled surfaces with some clearance is presented. It is proposed that the onset conditions, which describe whether the ice-volume fraction in a steady state is greater than or less than that without heat-conducting plates, are defined by the dimensionless distances between the heated/cooled walls and the heat-conducting plates. It is shown that the onset conditions are dependent on the pitch and the thickness of the heat-conducting plates and are less dependent on the thermal conductivity of the plates.
The report gives results of an analysis of the effect of the availability of a flue gas desulfurization system on the ability of an individual power plant to generate electricity at its rated capacity. (The availability of anything is the fraction of time it is capable of service, whether or not it is actually in service.) Also analyzed are its effects on a power generating system (a group of several coal-, oil-, and gas- fired power plants plus nuclear and hydroelectric plants).
This journal article reports a study originally intended to examine the microbial composition of Octopus Spring and nearby vent biofilms. The article compares the lipid profiles of several genera within the Aquificales as well as measurements of the isotopic carbon fractionation associated with autotrophic and heterotrophic growth of Thermocrinis ruber. Results of the study have led to improved understanding of population structure in the Octopus Spring pink streamer community, a hyperthermophilic chemolithotrophic ecosystem in Yellowstone National Park.
The evaluation of radon concentration measurements in newly developing geothermal reservoirs with the objective of determining the ability of measured changes in noncondensible gas components, such as radon, to predict changes in the thermodynamic properties of the reservoir is described. This ability would be especially useful in liquid-dominated resources, where changes in steam fraction are sensitive to changes in reservoir temperature and fluid enthalpy. Radon measurements were made in samples separated by phase at the outlets of a prototype rotary separator turbine. The data were examined in relation to the thermodynamic properties of the geofluids supplied by the test well.
Radioiodinated ..cap alpha..-bungarotoxin, the venom of Bungarus multicinctus, is commonly used for the detection and quantification of nicotinic acetylcholine receptors (nAChR) and anti-nAChR antibodies. A radioiodination method is described which is simple and yields a fully active product which, after fractionation, has a specific activity tenfold higher (900 Ci/mmol) than those routinely used, resulting in enhanced sensitivity of assays and conservation of material, especially muscle extracts.
A method for analyzing the experimental results of coal liquefaction reactions which is applicable to a number of aspects of coal liquefaction research and process control, including rapid selectivity and performance screening for catalysts; correlation of laboratory results with process parameters; and optimization of product yield with plant process conditions is described here. Ternary diagrams of product/by-product distributions for the coal liquefaction using Co/Mo catalysts combined with a hyperbolic relationship for the conversion of various hydrocarbon fractions can be used for catalyst screening. A hydrogen consumption diagram used to provide a more significant selectivity test than the hyperbolic correlation is also included. (BLM)
The intensity of the orthopositronium component and its lifetime have been measured in liquid nitrogen as a function of electric field. While the lifetime remains constant at about 12.5 ns, the fraction of positronium formed is about 20% at zero field and decreases monotonically to an asymptotic value near 6% as the field is raised to 3.2 MV m"-"1. The decrease is roughly exponential with a drop off rate of 2.0 MV m"-"1. The results are a further indication of the importance of Mogensen's spur mechanism in the positronium formation process. (author).
Topological Chern-Simons theory coupled to matter fields is analysed in the framework of Dirac's method of quantising constrained systems in a general class of linear, non-local gauges. We show that in the weak coupling limit gauge invariant operators in the theory transform under an exchange according to a higher dimensional representation of the braid group which is built out of the fundamental representation matrices of the gauge group and thus behave like anyons. We also discover new solutions of the Yang-Baxter equation which emerges as a consistency condition on the structure functions of the operator algebra of the matter fields. (orig.).
The isotopic enrichment of copper ions in a positive column Cu-Nu discharge using optogalvanic excitation is analyzed with a rate equation model With excitation at 510.6 nm, the fraction of the ions belonging to the 63-amu isotope of copper is enriched relative to the neutral abundance. Enrichment as large as 10% is calculated when the initial abundance of the neutral isotope is small (< or =0.1) and the discharge current density is large (> or =75 mA/cm/sup 2/). The degree of enrichment is examined as a function of the initial abundance, discharge current, the rate of charge exchange, and the diameter of the discharge tube.
Non-thermal plasma treatment is a promising technique for the destruction of volatile organic compounds in waste gas. A relatively unexplored technique is the atmospheric negative dc multi-pin-to-plate glow discharge. This paper reports experimental results of allyl alcohol degradation and ozone production in this type of plasma. A new model was developed to describe these processes quantitatively. The model contains a detailed chemical degradation scheme, and describes the physics of the plasma by assuming that the fraction of electrons that takes part in chemical reactions is an exponential function of the reduced field. The model captured the experimental kinetic data to less than 2 ppm standard deviation.
Nano-materials in which a large fraction of atoms resides within a few atomic layers near the surface can be designed to have novel properties by manipulating their surface parameters. We show that the effective elastic constants of nano-porous/cellular materials can be made to exceed those of the parent materials provided the pore surface elastic parameters satisfy certain conditions. These stiff nano-porous materials herald a radical breakthrough in sandwich-type construction.
Nano-materials in which a large fraction of atoms resides within a few atomic layers near the surface can be designed to have novel properties by manipulating their surface parameters. We show that the effective elastic constants of nano-porous/cellular materials can be made to exceed those of the parent materials provided the pore surface elastic parameters satisfy certain conditions. These stiff nano-porous materials herald a radical breakthrough in sandwich-type construction.
NIST radon standards are hermetically sealed polyethylene capsules filled with {sup 226}Ra solution. Recently, four new series of standards with activities 5, 50, 500, and 5000Bq were prepared. The measured emanation fraction agrees with a calculation that accounts for the radon accumulated inside the polyethylene walls of the capsule. Obtained solubility of radon in polyethylene is approximately 45 of the solubility of radon in water. The radon diffusion coefficient in low-density polyethylene is 7.2x10{sup -8}cm{sup 2}/s.
Processes of production and purification (necessary for fabricating fuel elements) of powdery uranium dioxide with particle size up to 1000 #mu#m and more have been studied. Developed is continuous process of UO_2 production with above particle size by converting uranium hexafloride into UO_2 solid particles in fluidized bed while their interaction with water vapor and hydrogen on the uranium dioxide nucleus material. The method allows to conduct continuous selection from the apparatus of UO_2 powder fraction with particle size near 1000 #mu#m without nucleus material additional feed.
Using Southern, dot-blot and 'in situ' hybridization, molecular and cytological localization of repetitive 'Lupinus lueteus' DNA sequence was shown. Under CsCl gradient centrifugation conditions CG-rich satellite fraction appeared. Dot-blot hybridization clearly indicated that 1070bp repetitive element being a member of previously described EcoRI fragments family appeared only in the main band. The use of that DNA fragment as an 'in situ' hybridization signal in the euchromatin area. (author). 26 refs, 3 figs.
An investigation of the solidification behavior was carried out on the directionally solidified single crystal superalloy CMSX 6. The relationship between structure morphology and the process parameters has been experimentally determined and illustrated in a solidification diagram. The metallographic analyses of transverse sections within the solidification interval yield the sequence of phase formation and the evolution of solid fraction. The solidification process and the corresponding structure have been discussed in detail. (orig.)
The stability constant values of Pa(V) with some complexing ligands (chloride, sulfate and oxalate) are graphically determined using solvent extraction data. The organic phase was at constant composition of HTTA in benzene while the aqueous phase was held at constant hydrogen ion concentration and ionic strength of 3. The curve-fitting method was adopted throughout this investigation, giving the following values. The stability constants obtained are used to calculate the distribution of the different Pa (V) species in the corresponding aqueous phase (expressed in mole fraction) as a function of ligand ion concentration.
There is investigated the role of polymer layers on the metal surface of a fine filler in the formation of a PVC system with electrophysical properties. It is shown that a physicochemical polymer modification takes place under the surface active center influence. Thus, the surface layer properties (density and geometrical characteristics) differ from the PVC ones. The correlation between the electrophysical properties of the PVC composite and the surface layer in the range of the fine copper fraction of 0?11.3 vol % at E ? 106 V m?1 and a frequency response of 20?2 ? 105 Hz is determined. An explanation of the investigated relation is presented.
We provide a scenario in which a hidden U(1) gauge boson constitutes dark matter of the Universe and decays into the standard-model particles through a kinetic mixing with an $U(1)_{B-L}$ gauge boson. Interestingly, our model can naturally account for the steep rise in the positron fraction recently reported by PAMELA. Moreover, we find that due to the charge assignment of $U(1)_{B-L}$, only a small amount of antiprotons are produced in the decay, which is also consistent with the PAMELA and other observational data.
Low-dust flue gases can be washed efficiently of SO/sub 2/, and the flue gas heat can be utilized. The residual heat fraction still required by the process is characterized by a temperature of 15/sup 0/K above the temperature of the purified flue gas. Marketable crystalline ammonium sulfate is produced. The high efficiency and low heat consumption are achieved by combining all process stages in a single, fully integrated cycle process free of heat and materials losses. The process is characterized by high efficiency, low investment and operating costs, recovery of thermal energy, and production of an ammonium sulfate fertilizer.
A theory of nonunitary-invertible as well as unitary canonical transformations is formulated in the context of Weyl's phase space representations. Exact solutions of the transformation kernels and the phase space propagators are given for the three fundamental canonical maps as fractional-linear, gauge and contact (point) transformations. Under the nonlinear maps a phase space representation is mapped to another phase space representation thereby extending the standard concept of covariance. This extended covariance allows Dirac-Jordan transformation theory to naturally emerge from the Hilbert space representations in the Weyl quantization.
Recent surveys of supergiants stars in the LMC indicate that the post-main-sequence region of the colour-magnitude diagram is well populated, although numerical evolution of massive stars with normal surface hydrogen indicates to the contrary. Supergiant stars having surface enrichment of helium acquired for example from a previous phase of accretion from a binary companion, however, evolve in a way so that the evolved models and observed data are consistent. We compare the available data with computed evolutionary tracks of massive stars of metallicity relevant to the LMC with and without helium-enriched envelopes and conclude that a large fraction of supergiant stars may occur in binaries. (author).
The production and uses are described for extracellular microbial polysaccharides (generically called emulsans) and for a new class of extracellular microbial protein-associated lipopolysaccharides (collectively called alpha-emulsans) produced by Acinetobacter Sp. ATCC 31012, its mutants or recombinants. Also included are the deproteinized lipopolysaccharides (collectively called apoemulsans) obtained from such emulsans, as well as to the divalent metal, ammonium, and quaternary ammonium salts of such emulsans and apoemulsans. The materials can be used (1) in cleaning oil-contaminated vessels used to transport or store crude oil or petroleum fractions in such a manner that the residual oil may be recovered for fuel value or for refining and (2) in enhanced oil recovery.
A nanoparticle generator based on the principle of electrical discharge (PALAS GFG-1000) was used to produce nanoparticles of different chemical natures. The fractions of electrically neutral particles were then measured by means of a Spectrometre de Mobilite Electrique Circulaire (SMEC, i.e. radial-flow mobility analyzer) for different operating conditions. The experimental results were compared with the theoretical values calculated from the Fuchs extended charge equilibrium model for spherical particles and agglomerates. For the smallest particles (below 20 nm), the deviations observed remain below 10%, and tend towards 20% for larger particles (over 35 nm).
Studies dialysis kinetics of zinc dialkyldithiophosphates, detergent-dispersing agents, alkyl-phenols and base oils. It was established that diffusion kinetics of oil hydrocarbons through membrane of individual compounds and narrow fractions is described by Brinzinger's formula, which is identical to the kinetic reaction formula of the 1st order. It was shown that dialysis can be utilized to determine the content of the ''active substance'' only in sulphonate and alkylsalycilate additives. Increasing temperature from 20 to 40/sup 0/ results in an increased dialysis constant for all studied products by 1.4-1.9 times.
Hydrogenolysis reactions of a mixture of coal liquid and coal liquefaction residue were carried out using red mud - sulfur or Co-Mo/Al{sub 2}O{sub 3} catalyst. The effect of deashing treatment of coal liquefaction residue were also investigated. Notable synergistic effects such as the increase of n-hexane soluble and the decrease of dichloromethane insoluble were observed only with the hydrogenolysis of the basic fraction of coal liquid and nondeashed coal liquefaction residue using red mud-sulfur catalyst. 4 refs., 2 figs., 2 tabs.
Studies have shown that CCl_4 administration to rats inhibits endoplasmic reticulum calcium pump activity and reduces the amount of calcium associated with subsequently isolated microsomal subcellular fractions. This report confirms that exposure of isolated hepatocytes to CCl_4 rapidly produces these effects in isolated parenchymal cells and demonstrates that when isolated hepacytes are exposed to CCl_4 calcium is rapidly released from cells. This release can be detected with a calcium ion-selective electrode when cells are incubated in a medium with low extracellular calcium. Calcium released from an intracellular pool(s) may initiate hepatotoxic changes in liver. (author).
Measurements of carbon metabolism, production and exchange along food webs suggest that large fractions of the organic matter produced on continental shelves must be exported to continental slopes. The annual loss of organic matter from continental shelf ecosystems is far greater than in the open ocean. If part of the loss of nearshore primary production has increased in those coastal zones where anthropogenic inorganic nutrient supplies have been consistently increasing since the industrial revolution, then burial and diagenesis of this material in slope depocentres could represent the missing BMTs of carbon in global CO/sub 2/ budgets.
We use the bulge Sersic index n and bulge-to-total mass ratio (B/T) to explore the fundamental question of how bulges form. We perform two-dimensional bulge-disk-bar decomposition on H-band images of 143 bright, high-mass (M _* #>=# 1.0 x 10"1"0 M _s_u_n) low-to-moderately inclined (i < 70"0) spirals. Our results are as follows. (1) Our H-band bar fraction (#approx#58%) is consistent with that from ellipse fits. (2) 70% of the stellar mass is in disks, 10% in bars, and 20% in bulges. (3) A large fraction (#approx#69%) of bright spirals have B/T#<=# 0.2, and #approx#76% have low n #<=# 2 bulges. These bulges exist in barred and unbarred galaxies across a wide range of Hubble types. (4) About 65% (68%) of bright spirals with n #<=# 2 (B/T #<=# 0.2) bulges host bars, suggesting a possible link between bars and bulges. (5) We compare the results with predictions from a set of #LAMBDA#CDM models. In the models, a high-mass spiral ...
Olive mill effluent (OMW) is an example of a wastewaters containing high concentrations of recalcitrant and toxic compounds which are polyphenolics of different molecular weight. It causes disposal problems because they contain powerful pollutants. Treatment and detoxification of phenolic fraction extracted from olive mill wastewaters as well as a synthetic phenolic mixture was investigated by electro-Fenton method. Results shows that this method is highly efficient in polymerising low molecular mass phenolics and removing a large amount of recalcitrant polyphenolic compounds. This treatment decreased 78% of the toxicity which sustained a good anaerobic post-treatment. (orig.)
The magnetic and electronic properties of non-Fermi liquid UCu{sub 4Pd} depend on annealing conditions. Local structural changes due to this annealing are reported from UL{sub III}- and Pd K-edge x-ray absorption fine-structure measurements. In particular, annealing decreases the fraction of Pd atoms on nominally Cu 16e sites and the U-Cu pair-distance distribution width. This study provides quantitative information on the amount of disorder in UCu{sub 4Pd} and allows an assessment of its possible importance to the observed non-Fermi liquid behavior.
We show that specially designed two-dimensional arrangements of full elastic cylinders embedded in a nonviscous fluid or gas define (in the homogenization limit) a new class of acoustic metamaterials characterized by a dynamical effective mass density that is anisotropic. Here, analytic expressions for the dynamical mass density and the effective sound velocity tensors are derived in the long wavelength limit. Both show an explicit dependence on the lattice filling fraction, the elastic properties of cylinders relative to the background, their positions in the unit cell, and their multiple scattering interactions. Several examples of these metamaterials are reported and discussed.
We iterate Manolescu's unoriented skein exact triangle in knot Floer homology with coefficients in the fraction field of the group ring (Z/2Z)[Z]. The result is a spectral sequence which converges to a stabilized version of delta-graded knot Floer homology. The (E_2,d_2) page of this spectral sequence is an algorithmically computable chain complex expressed in terms of spanning trees, and we show that there are no higher differentials. This gives the first combinatorial spanning tree model for knot Floer homology.