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It was recently shown that the use of Coulomb logarithms appropriate for bremsstrahlung radiation (rather than transport processes) along with corrections for the Langdon effect and ion screening reproduced measurements of collisional absorption in well-characterized underdense plasmas [D. Turnbull et al., Phys. Rev. Lett. 130, 145103 (2023)]. However, it was recognized at the time that the use of the standard absorption-reduction factor from Langdon's seminal paper was inconsistent with the use of Coulomb logarithms that are thermally averaged over a Maxwellian electron-velocity distribution function. A more accurate approach would be to average over the expected super-Gaussian distribution function while accounting for the Gaunt factor's velocity dependence, which somewhat mitigates the Langdon effect; however, at that time, this theory matched the data less well. This conflict is now eliminated with the additional insight that the ionization state of our mid-Z ion species (when present) was lower than had been assumed, as evidenced by the Thomson-scattering data and time-dependent Cretin simulations. We are now able to show that an improved treatment of the Langdon effect provides the best match to data. Otherwise, the prior conclusions remain unchanged. We also show an example of the substantial expected impact to the absorption rate in calculations of indirect-drive hohlraums. [ABSTRACT FROM AUTHOR]

The purpose of this study is to verify the moderating effects of consultant's problem-solving ability on the effect of client advance readiness on consulting satisfaction. The survey subjects were the employees who participated in internal consulting project with external professional consultants and questionnaire method was used. The survey was conducted through e-mail and direct questionnaire responses for about 2 months from February 2017. 500 questionnaire were distributed, and 276 responses were finally used for the analysis. Statistical program SPSS 23.0 was used to analyze the validity and reliability, followed by the moderating regression analysis to verify the hypothesis. The result of this study showed that client's advance readiness for consulting had a significant effect on consulting satisfaction. In addition, consultant's problem-solving ability was confirmed to have a significant moderating effect on the influence of client's advance readiness on consulting satisfaction. This study provides implications for the consultant's role as well as the importance of client's advance readiness for consulting before proceeding the consulting project to improve consulting satisfaction of the company using consulting service. Future studies are required to find out various methods to improve client's advance readiness before consulting project and consultant's problem-solving ability. [ABSTRACT FROM AUTHOR]

X-ray free-electron lasers (XFELs) provide unique opportunities to generate and investigate dense plasmas. The absorption and transmission properties of x-ray photons in dense plasmas are important in characterizing the state of the plasmas. Experimental evidence shows that the transmission of x-ray photons through dense plasmas depends greatly on the incident XFEL intensity. Here, we present a detailed analysis of intensity-dependent x-ray transmission in solid-density aluminum using collisional-radiative population kinetics calculations. Reverse saturable absorption (RSA), i.e., an increase in x-ray absorption with intensity has been observed for photon energies below the K-absorption edge and in the intensity range of 1016–1017 W/cm2 for XFEL photons with 1487 eV. At higher intensities, a transition from RSA to saturable absorption (SA) is predicted; thus, the x-ray absorption decreases with intensity above a threshold value. For XFEL photon energies of 1501 eV and 1515 eV, the transition from RSA to SA occurs at XFEL intensities between 1017–1018 W/cm2. Electron temperatures are predicted to be in the range of 30–50 eV for the given experimental conditions. Detailed population kinetics of the charge states explains the intensity-dependent absorption of x-ray photons and the fast modulation of XFEL pulses for both RSA and SA. [ABSTRACT FROM AUTHOR]

A material capsule system has been developed for irradiation tests of nuclear materials in the core region of the high-flux advanced neutron application reactor (HANARO) and has been actively utilized for the various material irradiation tests requested by numerous users. For an irradiation test in the reactor, nuclear characteristics and irradiation temperature of the capsule parts are essential for the safety analysis of the capsule and for the detailed capsule design. The irradiation temperature and neutron fluence of the specimens are key parameters required by a user to analyze any neutron irradiation damage effects. Based on a basic design of a capsule, the reactivity effect, neutron flux/fluence, and gamma heating of specimens are calculated by the MCNP code. To compare the calculated neutron fluence of the specimens, thermal and fast fluence monitors (F/Ms) are installed in a capsule. After an irradiation, the F/Ms are dismantled and analyzed to obtain a neutron spectrum. The experimental fast neutron fluences (E>1.0\ MeV) derived by using the SAND II code were found to lie within about 20% of the predicted values calculated by the MCNP code. The irradiation temperature of the specimens is analyzed preliminary by using the GENGTC or ANSYS codes based on the basic design of a capsule and gamma heating. During an irradiation test, the temperatures of the specimens in a capsule are measured and monitored by thermocouples. The displacement per atom (DPA) and activation of the irradiated specimens are also evaluated by using the SPECTER and ORIGEN2 codes, respectively, at HANARO. [ABSTRACT FROM PUBLISHER]

This study attempts to determine changes in carpal canal volume with distraction across the wrist. Uniform longitudinal distraction was maintained with two external fixators on the radial and ulnar aspects of the forearm axis of five cadaver specimens. After CT scanning, volume determinations were made at 5 mm increments beginning at the lunocapitate joint to a point 1.5 cm distal to the middle finger carpometacarpal joint. There was a statistically significant decrease of the mean total carpal canal volume from 0 to 4.54 kg of distraction, with no statistically significant decrease from 0 to 2.27 kg or 2.27 to 4.54 kg. The largest decrease occurred at 15 and 20 mm distal to the proximal edge of the transverse carpal ligament corresponding to the level of the hamate hook. Reduction in mean carpal canal volume was 10.2% and 7.5% at these distances, respectively, from 0 to 4.54 kg of distraction. Progressive distraction across the wrist causes a decrease in total carpal canal volume. [ABSTRACT FROM PUBLISHER]

A core-shell of a carboxylic functional polystyrene (PS-COOH) with gold was prepared by the combination of surface gold-seeding and subsequent shell growth in a gold solution. The PS-COOH cores were prepared by a dispersion polymerization of styrene for seed formation followed by copolymerization of styrene and methacrylic acid. In the preparation of gold shell, PS-COOH cores were initially immersed into gold nanoparticles containing solution and continuous gold shell was formed by employing a mixed aqueous solution of Au(OH)3 and NH2OH. The gold nanoparticles impregnated into the PS-COOH cores were used as gold seeds to form continuous gold shells. The characteristics of the PS-COOH/Au core-shells were investigated by SEM, TEM, EDS and XPS. [ABSTRACT FROM AUTHOR]

A dry type conducting polymer actuator PEDOT/NBR/PEDOT is prepared. Nitrile rubber (NBR) containing room temperature ionic liquid, 1-butyl-3-methyl imidazoliumbis (trifluoromethylsulfonyl) imide (BMITFSI), have been utilized as a new type of solid polymer electrolytes. Various types of NBR having different amounts of acylonitrile (ACN), viz. 23, 35, and 40 mol.%, are synthesized in order to examine the effect of polarity of NBR on the actuation behavior. A conducting polymer, poly(3,4-ethylenedioxythiophene) (PEDOT), was synthesized on the surface of the SPEs by using a chemical oxidative polymerization technique. The electrical potential was applied on PEDOT layer which caused volume change to result in actuation behavior. The characteristics of the PEDOT/NBR/PEDOT actuator were carefully examined. [ABSTRACT FROM AUTHOR]

The thin layer of poly(3, 4-ethylenedioxythiophene) (PEDOT) on the PET film was obtained by a vapor-phase polymerization technique using HAuCl4 as an oxidant. The EDOT monomer was easily oxidized by the HAuCl4 oxidant while HAuCl4 was reduced to form metallic Au nanoparticles. The formation of PEDOT/Au composite film was monitored by UV-vis spectra and SEM, and the formation of metallic Au was confirmed by EDAX and XPS. [ABSTRACT FROM AUTHOR]

The fabrication of a dry type conducting polymer actuator is presented using nitrile rubber (NBR) as the base material for the solid polymer electrolyte. A conducting polymer, poly(3,4-ethylenedioxythiophene) (PEDOT), was synthesized on the surface of the NBR by the chemical oxidation polymerization technique, and room temperature ionic liquids (RTIL) based on imidazolium salts, viz. 1-butyl-3-methyl imidazolium X [where X = BF4-, PF6-, (CF3SO2)2N-], were introduced onto the composite film. The effects of the anion size of the ionic liquids on the displacement of the actuator were investigated. The displacement increased with increasing anion-size of the ionic liquids. The cyclic voltammetric responses and the redox switching dynamics of the actuators were studied in different ionic liquids. [ABSTRACT FROM AUTHOR]

A novel Au/PDVB core-shell was prepared by the chemical reduction of a gold-phenanthroline complex on the poly(divinylbenzene) (PDVB) cores (2-5 μm). The PDVB cores were synthesized by precipitation polymerization, and the surface was modified by introducing thiol and sulfonic acid groups. The degree of sulfonation was measured according to its ion exchange capacity (IEC, 5.72 meq/g), and the surface concentration of thiol group was examined by FT-IR spectroscopy. The modified PDVB cores was immersed in a solution of a gold-phenanthroline complex and subsequently reduced to form gold seeds. The effects of the functional groups on the PDVB cores on fabrication of the gold core shell structure were examined. [ABSTRACT FROM AUTHOR]

This paper presents a wheel slip control for the anti-lock brake system (ABS) of a passenger vehicle using a controllable electrorheological (ER) valve pressure modulator. As a first step, the principal design parameters of the ER valve and hydraulic booster are appropriately determined by considering the braking pressure variation during the ABS operation. An electrically controllable pressure modulator is then constructed and its pressure controllability is evaluated empirically. Subsequently, a quarter-car wheel slip model is established and integrated with the governing equation of the pressure modulator. A sliding mode controller to achieve the desired slip rate is then designed and implemented via the hardware-in-the-loop simulation (HILS). Braking control performance and road transition control response are evaluated and presented in the time domain. [ABSTRACT FROM AUTHOR]

The fabrication of dry type conducting polymer actuator was presented. In the preparation of actuator system, nitrile rubber (NBR) was used as a base material of the solid polymer electrolyte. Thin films of NBR (150 ~ 200 µm) were prepared by compression molding process. The conducting polymer, polypyrrole(PPy) was synthesized on the surface of NBR by chemical oxidation polymerization technique, and the room temperature ionic liquid, 1-butyl-3-methylimidazolium bis(trifluoromethyl sulfonyl)imide (BMITFSI) was introduced into the composite film. The cyclic voltammetry responses and the redox switching dynamics of PPy in NBR/ionic liquid solid polymer electrolyte were studied. The displacement of actuator was measured by laser beam. [ABSTRACT FROM AUTHOR]

As a novel candidate of electrorheological (ER) material, core/shell composite particles (PAPMMA) of poly(methyl methacrylate) (PMMA) core and polyaniline (PANI) shell were prepared and adopted as a dispersed phase. PAPMMA particles, obtained by a dispersion polymerization method, were spherical and possessed a monodisperse particle size distribution, in which the PANI shell was introduced on the surface of PMMA via an in-situ polymerization of aniline by adding an oxidant in an aqueous acidic solution. Yield stress of the PAPMMA suspensions under an applied electric field was observed to be increased with a particle size. In addition, monodisperse acrylic microspheres with aniline moiety on the surface were prepared by a seeded emulsion method, and then composite particles possessing chemically bonded PANI shell (PA-PGMA) were prepared via an in-situ polymerization of aniline. Their ER characteristics were also examined. [ABSTRACT FROM AUTHOR]

Carbonyl-iron (CI) based magnetorheological (MR) fluid containing submicron-sized additive particles was prepared. The flow behavior at steady and oscillatory shear modes was investigated by comparing flow properties of CI-mineral oil suspensions without an additive via precise control of magnetic field strength. To enhance the dispersion stability and to examine submicron-sized filler effect for the CI suspensions, organically modified montmorillonite (organoclay) was added to the CI suspensions. In addition, with the precision control of magnetic field strength, we examined the novel features of submicron-sized particle filled CI suspensions, especially under weak magnetic field strengths, in steady shear modes; a temporal decrease of steady shear viscosity in sweeping magnetic field strengths was observed. [ABSTRACT FROM AUTHOR]

In this work, an electrically controllable anti-lock brake system (ABS) for passenger vehicle is developed by utilizing electrorheological (ER) fluid. A pressure modulator which consists of a cylindrical ER valve and the hydraulic booster is constructed in order to achieve sufficient brake pressure variation during ABS operation. The principal design parameters of the modulator are determined by considering ER properties as well as required braking pressure. After investigating pressure controllability of the modulator, a vehicle model which is integrated with the proposed pressure modulator is formulated to design yaw rate controller. A sliding mode controller is designed to obtain desired yaw rate, and the friction forces between roads and wheels are estimated via the estimator. Braking performances of the proposed ABS under various roads are evaluated through the hardware-in-the-loop-simulation (HILS) and the steering stability during braking operation is demonstrated by undertaking split-μ test. [ABSTRACT FROM AUTHOR]

We synthesized multi-walled carbon nanotube(MWNT)/polyaniline(PANI)nanocomposites from an oxidative dispersion polymerization using poly(vinyl alcohol)(PVA)as a polymeric stabilizer. Purified MWNT whose metallic catalysts have been removed in acidic media was applied. The formation of nanocomposites and their morphology were confirmed by both scanning electron microscopy(SEM)and transmission electron microscopy(TEM). Electrorheological properties were further characterized by a rotational rheometer equipped with a high voltage generator. [ABSTRACT FROM AUTHOR]

A core/shell particle with a poly(methyl methacrylate) (PMMA) core and a conducting polyaniline (PANI) shell was prepared and used as a dispersed phase for an electrorheological (ER) fluid, which is a suspension of polarizable particles in a non-conducting medium. PMMA particles, which were obtained using the dispersion polymerization method and spherical in shape with a monodisperse size distribution, were used as the core material for three different particle sizes. A PANI shell was introduced to the PMMA particle surface through in situ polymerization of aniline by an oxidant within an aqueous acidic solution, and its thickness was controlled via the amount of aniline monomer. These synthesized particles were dispersed in a silicone oil to prepare an ER fluid. The ER fluid, possessing Newtonian characteristics in the absence of an external electric field, exhibited a viscoelastic solid behavior with a non-vanishing yield stress, which were systematically controlled by the applied electric field strengths. [ABSTRACT FROM AUTHOR]

This paper presents a sliding mode control for a new anti-lock brake system (ABS) of a passenger vehicle using electrorheological (ER) valves. The Bingham model of an ER fluid is empirically obtained as a function of electric fields, and it is incorporated with the dynamic model of ER valves. The design parameters of the ER valves such as electrode gap are appropriately determined by considering braking forces required for a small-sized passenger vehicle. An electrically controllable ABS using the ER valves is then proposed and its governing equations of motion are derived. Subsequently, sliding mode controllers are formulated for wheel slip control as well as yaw rate control. In the formulation of the sliding mode controllers, the friction force which is difficult to measure in real time is estimated via a sliding mode observer associated with the fuzzy algorithm. Computer simulations for braking performance and steering stability under various road conditions are undertaken in order to demonstrate the effectiveness of the proposed ABS. [ABSTRACT FROM AUTHOR]

The electrorheological (ER) fluids exhibit a drastic change in rheological and electrical properties. Among these properties, yield stress is one of the critical evaluation parameters of the performance of ER devices. The published experimental data of yield dependence on the electric field strength and particle volume fraction are inconsistent due to the time dependence of material properties and measuring conditions. In this paper, we present a universal function, descriptive of the normalized yield stress, via scaling of the applied electric field strength. This scaling equation hybridizes both the polarization and conductivity models. Yield stress data for various ER fluids are collapsed onto a single curve for a broad range of electric field strengths, suggesting that the proposed scaling equation is adequate for predicting the ER property. Furthermore, the yield stresses, obtained from two different measuring techniques (static and dynamic methods), were also examined. [ABSTRACT FROM AUTHOR]

Increased expression of VEGF in several types of tumours has been shown to correlate with poor prognosis. We used a replication-deficient adenoviral vector containing antisense VEGF cDNA (Ad5CMV-αVEGF) to down-regulate VEGF expression and increase the efficiency of delivery of the antisense sequence in the human breast cancer cell line MDA231-MB. Transfection of these cells with Ad5CMV-αVEGF in vitro reduced secreted levels of VEGF protein without affecting cell growth. Moreover, injection of the Ad5CMV-αVEGF vector into intramammary xenografts of these cells established in nude mice inhibited tumour growth and reduced the amount of VEGF protein and the density of microvessels in those tumours relative to tumours treated with the control vector Ad5(dl312). Our results showed that antisense VEGF[SUB165] cDNA was efficiently delivered in vivo via an adenoviral vector and that this treatment significantly inhibited the growth of established experimental breast tumours. The Ad5CMV-αVEGF vector may be useful in targeting the tumour vasculature in the treatment of breast cancer. [ABSTRACT FROM AUTHOR]

We report our experimental results on the electrorheological (ER) characteristics of ER fluids consisting of suspensions of semiconducting polyaniline and copolyaniline particles in silicone oil. Ionic sodium diphenylamine sulfonate and nonionic o-ethoxyaniline were introduced to synthesize copolyanilines, i.e. N-substituted copolyaniline and poly (aniline-co-o-ethoxyaniline), respectively. ER fluids using these particles were compared. ER fluids, which contain the ionic copolymer, showed the highest ER performance among polyaniline and its copolymer systems. This result was interpreted in terms of the conductivities of the particles and their dielectric spectra. [ABSTRACT FROM AUTHOR]

Gelation properties of 4 major protein additives were measured with and without salt during various hydration times. As hydration time increased, stress and strain of beef plasma and egg white gradually decreased regardless of salt. Unsalted whey proteins did not form a gel until the hydration time reached 48 h. Stress values of salted beef plasma with no hydration were significantly high. Soy protein isolate did not form a measurable gel at 9% concentration regardless of the presence of salt under rheological instruments, however its denaturation temperature was detected under DSC. Effect of salt on gel color was more pronounced with whey protein concentrate. [ABSTRACT FROM AUTHOR]