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A mobile radon calibration system was developed with a high-sensitivity radon detector, a movable calibration chamber, and a 226Ra solid source at the Korea Research Institute of Standards and Science (KRISS). The high-sensitivity radon detector was based on electrostatic collection mechanism. The volume of the calibration chamber was (1003.8 ± 6.0) L. The mobile radon calibration system was calibrated with 222Rn CRM from the radon primary system at KRISS. The sensitivities were established to be (231.8 ± 16.1) cpm/(kBq/m3) for 218Po and (254.9 ± 17.8) cpm/(kBq/m3) for 214Po, respectively (k = 2).

In this study, oil degrading bacteria discovered from fish living near the oil ports at Karachi in Pakistan were characterized. The bacteria isolated from skin, gills, and gut in fish could consume crude oil as a source of carbon and energy. Total 36 isolates were tested using Nutrient Agar (NA) and MSA media with different crude oil concentrations (0.2%, 0.5%, 0.7%, 1%, 2%, and 5%) and 4 out of 36 isolates (two Gram positive and two Gram negative bacteria) were selected for further identification. 16S rRNA gene sequencing revealed that the isolates are related to Bacillus velezensis, Bacillus flexus, Pseudomonas brenneri and Pseudomonas azotoforman. Oil degrading potential of these bacteria was characterized by GC-MS analysis of degradation of oil components in crude oil as well as engine oil. We found that one (2, 6, 10, 14-Tetramethylpentadecane) out of 42 components in the crude oil was fully eliminated and the other oil components were reduced. In addition, 26 out of 42 oil components in the engine oil, were fully eliminated and the rest were amended. Taken together, these studies identify that B. velezensis, B. flexus, P. brenneri and P. azotoforman have high oil degrading potential, which may be useful for degradation of oil pollutants and other commercial applications.

It is important to understand what genetic risk factors lead to hypertension and how genotype-specific dietary and lifestyle modification can mitigate the risk of developing hypertension. The ATP2B1 rs17249754 gene, which encodes a calcium pump expressed in vascular smooth muscle was identified as having variants that conferred higher or lower risk of hypertension-with the major allele carriers being increased at risk. However, the effects of dietary intakes on risk of hypertension among carriers of the different alleles have not been fully elucidated. Therefore, we evaluated ATP2B1 rs17249754 and its interaction with dietary intakes of sodium (Na), potassium (K) and calcium (Ca) on the risk of developing hypertension using the Ansan/Ansung (n=8842) and City-Rural (n=5512) cohorts from the Korean Genome and Epidemiology Study. Carriers of the major allele of ATP2B1 rs17249754 were at greater risk of developing hypertension and high Na intake and low Ca increased the risk more in major allele than among minor allele carriers. High potassium intake was more protective against hypertension in the subjects expressing minor alleles and a low Na/K intake ratio was the most consistently beneficial to the subjects expressing the minor allele. When controlling for Na and K, low Ca intake was associated with a substantially higher risk for high systolic blood pressure in the major allele carriers compared with minor allele, suggesting good calcium status is especially important for the major allele carriers. In conclusion, people with the major allele of ATP2B1 rs17249754 are susceptible to hypertension especially in low intake of Ca and high ratio of Na and K.

Observations of galaxies and primordial radiation suggest that the Universe is made mostly of non-luminous dark matter. Several types of new fundamental particles have been proposed as candidates for dark matter such as weakly interacting massive particles (WIMPs) but no definitive signal has been seen despite concerted efforts by many collaborations. One exception is the much-debated claim by the DAMA collaboration of a statistically significant annual modulation in the event rate of their experiment with a period and phase consistent with that expected from WIMP dark matter. Several groups have been working to develop experiments with the aim of reproducing DAMA's results using the same target medium. Here we report results from the initial operation of the COSINE-100 experiment. COSINE-100 uses sodium iodide as the target medium-the same medium as DAMA-and is designed to carry out a model-independent test of DAMA's claim. Initial data based on the first 59.5 days indicate that there is no excess of events over the expected background, confirming that DAMA's annual modulation signal is in severe tension with results from other experiments under the assumption of dark matter having spin independent interactions and the Standard Halo Model. COSINE-100 is now taking data to study the presence of dark matter-induced annual modulation in the event rate of the sodium iodide detectors., 26 pages, 9 figures

In J-PARC heavy-ion project, we aim at studies of QCD phase structures and hadron properties in high baryon density close to the neutron star core. We have developed a heavy-ion acceleration scheme with a new linac and a new booster with existing two synchrotrons with the goal beam rate of about 10 11 Hz. We have also designed a large acceptance spectrometer based on a toroidal magnet. We have evaluated the spectrometer performance, and demonstrated reconstructing dielectron and dimuon spectra with full detector simulations. Finally, we designed a hypernuclear spectrometer which can utilize the full intensity ion beams.

Liquid scintillator is widely used in various fields. This paper proposes a new base material, a mixture of alcohol and water for liquid scintillator and introduces photo image analysis to investigate electron beam irradiation on the new alcohol-based liquid scintillator. A possibility of using alcohol as a new detection solution in particle detector is briefly described. Alcohol has good solubility for fluor, is biodegradable and has low toxicity. The development of an alcohol-based liquid scintillator was investigated and some physical and optical properties of the alcohol-based liquid scintillator were measured. The energy exchange process that the absorption spectrum overlaps with the emission spectrum was seen in our alcohol-based liquid scintillator. To date, there have been no R&D studies elsewhere for use of alcohol-based liquid scintillator in particle detectors. As an application, we introduce a new measurement technique where range measurements were achieved after irradiating an alcohol-based liquid scintillator with electron beam energies of 6–12 MeV. By analyzing the range images taken by digital camera, or even mobile phone camera, it was possible to find out the fluor component dissolved in the alcohol-based liquid scintillator. This method has sufficient potential as it enables us to estimate wavelengths in the visible region without using an expensive spectrophotometer. These results can be used in medical imaging applications for the treatment of tumors or cancers where irradiation by electron beams takes place. Furthermore, alcohol-based LS could be used in future, next generation particle detectors.

A key comparison has been made between the absorbed dose to water standards of the KRISS, Korea and the BIPM in accelerator photon beams. The results show the standards to be in agreement within the expanded uncertainty (k = 2) of the comparison of 12 parts in 103. The results are analysed and presented in terms of degrees of equivalence, suitable for entry in the BIPM key comparison database. Main text To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCRI, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

The Korea Research Institute of Standards and Science (KRISS) participated, in 2015, in an international Key Comparison (KC) of gaseous radon-222 activity named CCRI (II) -K2.Rn-222 to confirm international equivalence of KRISS-established gaseous radon-222 measurement standards. LNHB acted as KC pilot laboratory. This paper describes the KC measurement procedure followed at KRISS using the defined solid angle counting method together with auxiliary relative measurement methods and presents the results.

The Rare Isotope Science Project (RISP) is launched in Korea to build the IF and ISOL facilities. Current status of RISP is introduced.

Preliminary injunctions (PIs) are important in litigation in many settings, including antitrust, copyright, patent, trademark, employment and labor relations, and contracts. The filing of a PI and the court's ruling generate information that can impact settlement. We find that some plaintiffs request a PI to signal bounds on their damages in order to elicit better settlement offers. As a result, the parties are more likely to come to an out-of-court agreement permitting the disputed activity, compared to when a PI is motivated solely by defensive reasons to avert immediate damages during trial. Although the grant of a PI reduces ex post incentives for potential litigants to settle, this is more than offset by an increase in settlement upon a denial. Thus, ex ante, learning leads to more settlement. Nevertheless, the anticipation of learning and increased chances of settlement do not affect the initial filing decision. The Author 2012. Published by Oxford University Press on behalf of Yale University. All rights reserved. For Permissions, please email: journals.permissions@oup.com, Oxford University Press.

The aim of the RENO (Reactor Experiment for Neutrino Oscillation) is to measure the smallest neutrino mixing angle, θ 13 . The RENO detector consists of four concentric cylindrical layers: the target, γ - catcher , buffer and veto. Acrylic is used for the target and γ - catcher vessels, both of which contain liquid scintillator. Acrylic was chosen because it has good transmittance in the wavelength range of 400 – 430 nm and also does not react with liquid-scintillating solvents. In order to reduce systematic uncertainties, the target volume should be identical to a level of less than 0.1% between the near and far detectors. Furthermore, the acrylic vessel should not have any leaks. In this paper, we investigate the optical properties, design and construction of the acrylic vessels used in the RENO detector.

It is critical that the risk of lymph node metastasis (LNM) is evaluated for determining the suitability of endoscopic resection for T1 colorectal cancer (CRC). Reported risk factors for LNM in completely resected T1 CRC are deep submucosal invasion, grade 3, angiolymphatic invasion, and budding. The aim of the present study was to identify the histopathologic factors associated with LNM in T1 CRC.The study involved 435 patients with T1 CRC treated by endoscopic or surgical resection between January 2001 and April 2010 at the National Cancer Center, Korea. The 435 patients were classified into two groups - those undergoing surgical resection (n = 324) and those undergoing endoscopic resection (n = 111). In the surgically resected group, details regarding depth of submucosal invasion, angiolymphatic invasion, tumor grade, budding, and background adenoma (BGA) were evaluated with respect to presence or absence of LNM. In the endoscopically resected group, the results of follow-ups and additional salvage surgeries were studied.In the surgically resected group, LNM was detected in 42 patients (13.0 %). Grade 3, angiolymphatic invasion, budding, and the absence of BGA were identified as factors associated with LNM in univariate and multivariate analyses (P0.05). Among the 50 patients in the endoscopically resected group with high risk, three were diagnosed as being LNM-positive during the follow-up period. There was no LNM in the endoscopically resected group with low risk.Grade 3, angiolymphatic invasion, budding, and the absence of BGA are the risk factors that predict LNM in patients with T1 CRC. In cases where endoscopically resected T1 CRC has no risk factor, cautious follow-up could be recommended. However, if the tumor has any risk factor, additional surgical resection should be considered.

We suggest using spatial processing of the wave field with the aid of the double (in source and observer coordinates) weighted Fourier transform (DWFT) to suppress amplitude fluctuations (amplitude scintillations) during wave propagation in a randomly inhomogeneous medium. We examine the influence of sizes of receiving and transmitting antenna systems on the efficiency of the spatial processing in suppressing scintillations for both weak and strong intensity fluctuations. We demonstrate that the efficiency of the suppression of amplitude fluctuations by the inverse DWFT depends on the excess of sizes of fan beam projections of receiving and transmitting antenna systems over the Fresnel radius in a region with irregularities.

A modified fully thermally coupled distillation column is proposed, with utilization of the existing distillation columns of the conventional system, and its control scheme is suggested here. The proposed distillation system is applied to a benzene-toluene-xylene (BTX) separation process, of which the system design and control performance evaluation are conducted using the HYSYS software. The performance of the suggested 3 × 3 control is examined in the set-point tracking of product specification and the regulation for the changes of feed flow and composition. The pairings of three proportional-integral control loops are the reflux flow and the specification of overhead product, the prefractionator vapor flow and that of the side product, and the vapor boil-up rate and that of the bottom product. The multi-variable controllability using various indices is investigated for the proposed control scheme, and the controllability is compared with that of the cross-pairing between the control loops of the side and bottom products.

The first-order ionospheric error is reduced in the dual-frequency Global Navigation Satellite Systems (GNSS). In this paper, the possibility of eliminating ionospheric higher-order errors in the multifrequency GNSS is explored. Since the second-order error associated with the geomagnetic field effect on the refractive index can be eliminated in dual-frequency measurements, we explore the possibility of eliminating third-order errors in triple-frequency GNSS in view of phase scintillations. A connection between the possibility of improving the multifrequency GNSS accuracy and diffraction effects in radio signal propagation through the randomly inhomogeneous ionosphere is shown. The numerical simulation has revealed that the systematic, residual ionospheric error is considerably reduced when we pass on from dual-frequency to triple-frequency measurements. The change in the residual error variance during such a transition depends however on the relationship between the inner scale of the turbulent spectrum of ionospheric irregularities and the Fresnel radius. Given the inner scale larger than the Fresnel radius, not only the systematic error, but also the standard deviation reduces when we pass on from dual-frequency to triple-frequency measurements. Otherwise, when the Fresnel radius exceeds the inner scale, the variance increases with increasing number of frequencies in use.

Closely arranged CdSe and Zn doped CdSe vertical nanorod bundles were grown directly on FTO coated glass by using electrodeposition method. Structural analysis by XRD showed the hexagonal phase without any precipitates related to Zn. FE-SEM image showed end capped vertically aligned nanorods arranged closely. From the UV-vis transmittance spectra, band gap energy was found to vary between 1.94 and 1.98 eV due to the incorporation of Zn. Solar cell paramet- ers were obtained by assembling photoelectrochemical cells using CdSe and CdSe:Zn photoanodes, Pt cathode and polysulfide (1M Na2S + 1M S + 1M NaOH) electrolyte. The efficiency was found to increase from 0.16 to 0.22 upon Zn doping. Electrochemical impedance spectra (EIS) indicate that the charge-transfer resistance on the FTO/CdSe/polysul- fide interface was greater than on FTO/CdSe:Zn/polysulfide. Cyclic voltammetry results also indicate that the FTO/ CdSe:Zn/polysulfide showed higher activity towards polysulfide redox reaction than that of FTO/CdSe/polysulfide.

The second-order Rytov approximation has been used to determine ionospheric corrections for the phase path up to third order. We show the transition of the derived expressions to previous results obtained within the ray approximation using the second-order approximation of perturbation theory by solving the eikonal equation. The resulting equation for the phase path is used to determine the residual ionospheric first-, second- and third-order errors of a dual-frequency navigation system, with diffraction effects taken into account. Formulas are derived for the biases and variances of these errors, and these formulas are analyzed and modeled for a turbulent ionosphere. The modeling results show that the third-order error that is determined by random irregularities can be dominant in the residual errors. In particular, the role of random irregularities is enhanced for small elevation angles. Furthermore, in the case of small angles the role of diffraction effects increases. It is pointed out that a need to ...

We propose an efficient algorithm to calculate the radar cross section of electrically large and complex targets using a shooting and bouncing rays method. The proposed method, which is based on an angular division algorithm, reduces the number of initial rays and operations for each intersection test, and accelerates the ray tracing without loss of accuracy. Numerical results show the accuracy and efficiency of the proposed method.

This paper introduces a fast and efficient algorithm to calculate the radar cross section of complex targets using shooting and bouncing rays. The method combines a multiresolution grid division algorithm, with an algorithm that divides space using an octree structure. Applying the two division algorithms simultaneously, accelerates computation speed in ray tracing without reducing accuracy. Numerical results show the accuracy and efficiency of the proposed method.

With the growing interest in DC power transmission/distribution, the interest in the DC circuit breaker is also growing. The objectives of this paper are to propose a new type of inverse current injecting HVDC circuit breaker suitable for the multi-terminal network and to compare the result with the previous research. In addition, this paper uses the prototype produced to verify its feasibility through the current interruption test. The proposed DC circuit breaker provides ultra-fast interruption speed, and, while using a smaller capacitor, has higher interruption margin than that of the classical DC circuit breakers.

Development of tungsten brazing technology for the upgraded KSTAR divertor was launched in early 2013. ITER grade tungsten block was brazed on the CuCrZr alloy in vacuum at 980 °C for 30 minutes using silver free brazing alloy. A OFHC-copper was used as an interlayer between tungsten and the CuCuZr. The brazing alloy is a 0.05 mm thickness of plate of which component is a Ni-Cu-Mn. It is found that the optimal surface roughness on tungsten is about 6 µm Rs and the optimal loading on mock-up is about 20 kPa. Ultrasonic test, shear strength test, tensile strength test, and bend strength test were carried out to check the strength between tungsten and substrate material. And the joint conditions were analysed by scanning electron microscopy. Tungsten brazed mock-ups with a cooling tube were tested at the electron beam facility, KoHLT-EB in KAERI. The high heat flux test was performed for tungsten brazed mock-ups under heat flux of about 5 MW/m2 with more than 2,000 cycles. All the tungsten brazed mock-ups met the requirements and there was no delamination or failure at the bonding joints.

For KSTAR divertor, tungsten (W) monoblock has been considered as plasma facing components. W monoblock components consist of three parts; pure W as the plasma facing material, oxygen-free high conductive copper (Cu-OFHC) as the interlayer and CuCrZr alloy as the tube. Finite element analysis (FEA) is performed by using ANSYS WORKBENCH. In this paper, the hydraulic thermo-mechanical analysis is performed to investigate the optimal design parameters and the expected fatigue lifetime under the operating conditions in KSTAR. The design parameters, such as W armour thickness, monoblock side thickness and Cu-OFHC interlayer thickness, were found out by performing the steady state thermo-hydraulic analysis and thermo-mechanical analysis. And then, the equivalent total strains calculated by the mechanical analysis were applied to the experimental fatigue curves for CuCrZr-IG using the optimized W monoblock shape.

This paper investigates the third-order residual range error in the dual-frequency correction of ionospheric effects on satellite navigation. We solve the two-point trajectory problem using the perturbation method to derive second-approximation formulas for the phase path of the wave propagating through an inhomogeneous ionosphere. It is shown that these formulas are consistent with the results derived from applying perturbation theory directly to the eikonal equation. The resulting expression for the phase path is used in calculating the residual range error of dual-frequency global positioning system (GPS) observations, in view of second- and third-order terms. The third-order correction includes not only the quadratic correction of the refractive index but also the correction for ray bending in an inhomogeneous ionosphere. Our calculations took into consideration that the ionosphere has regular large-scale irregularities, as well as smaller-scale random irregularities. Numerical examples show that geomagnetic field effects, which constitute a second-order correction, typically exceed the effects of the quadratic correction and the regular ionospheric inhomogeneity. The contribution from random irregularities can compare with or exceed that made by the second-order correction. Therefore, random ionospheric irregularities can make a significant (sometimes dominant) contribution to the residual range error.

We present first measurements of the pseudorapidity and azimuth $(\eta,\phi)$ bin-size dependence of event-wise mean transverse momentum $ $ fluctuations for Au-Au collisions at $\sqrt{s_{NN}} = 200$ GeV. We invert that dependence to obtain $p_t$ autocorrelations on differences $(\eta_\Delta,\phi_\Delta)$ interpreted to represent velocity/temperature distributions on ($\eta,\phi$). The general form of the autocorrelations suggests that the basic correlation mechanism is parton fragmentation. The autocorrelations vary strongly with collision centrality, which suggests that fragmentation is strongly modified by a dissipative medium in the more central Au-Au collisions relative to peripheral or p-p collisions. \\

A fast method for ray tracing in high-frequency electromagnetic problems is proposed. The proposed method, which is based on adaptive space division using an octree structure, reduces the total CPU time needed to trace each ray while providing the same accuracy as conventional ray-tracing algorithms.

Gold strip bumps for electronic packaging are bonded using the thermosonic process. The Au strip bumps on the chip and substrate are aligned in a crossed configuration, and ultrasound is applied longitudinally on the chip to form a solid state bond between the crossed strip Au bumps. Deformed bump shapes are calculated numerically, and the shear force and fractured surface profile are measured to evaluate the bond quality. The deformed Au bump shape is similar to a saddle, which provides larger contact surface area and greater friction force. The bond strength of crossed strip bumps reaches the yield strength of Au, which is much higher than that previously obtained for bonding between Au bumps and a planar pad.

Research is carried out into scattering of waves by random strong anisotropic inhomogeneities when the inhomogeneities are in the distant zone according to one (transverse) scale and at the same time they are in the near zone according to another (longitudinal) scale. To analyse the formulas of the single scattering the stationary phase method in the longitudinal coordinate integral is used. It is shown that the angle sensitivity of strong anisotropic scattering, unlike weak anisotropic scattering, strongly depends on the longitudinal statistical homogeneity of the medium.

As there is substantial progress in the KSTAR tokamak engineering, all the major structures and sub-systems are under fabrication and in procurement phase. The vacuum vessel, port, cryostat cylinder, lid, and bellows are being rigorously fabricated in the factory. The lower part of the KSTAR such as cryostat base and gravity support has been almost finished in its fabrication. There are also great progresses and significant results in manufacturing of the superconducting magnet, including four Toroidal Field (TF) coils, lower and upper PF7 coils which are the largest Poloidal Field (PF) coils. The TF00 coil, which has been made for test and back-up of the TF magnet system, was successfully tested in the cool-down and current charging. As the fabrications and procurements of major structures have been actively proceeded, assembly works were also launched from Aug. 2003. More detailed description on these status, results, and plans will be described in this paper.

HANBIT is a magnetic mirror confinement device. Recently, after finishing the first campaign for the basic system development, it started the second campaign for high-temperature plasma confinement physics study in a mirror configuration. Here, we introduce briefly the HANBIT device and report initial physics experiment results on RF-plasma heating and confinement in the simple mirror configuration. It appears that the discharge characteristics of HANBIT are quite different from those in other mirror devices, and an explanation is presented to clarify the difference.

Carcass weight and backfat thickness are two of important elements in determining the carcass trait in pigs and are studied on animal genetics, nutrition, and endocrinology. Growth factors stimulate or inhibit the proliferation and differentiation of various cells. In particular, insulin-like growth factors (IGFs), transforming growth factor (TGF)-β, and epidermal growth factor (EGF) are involved in the growth and maintenance of muscle. Also, dehydroepiandrosterone-sulfate (DHEA-S) and cortisol are known to be related to the obesity and subcutaneous fat depth in pigs. Therefore, this study was performed to relate growth factors (IGFs, TGF-β1, and EGF) and hormones (cortisol and DHEA-S) concentrations at antemortem and postmortem periods to carcass traits including carcass weight and backfat thickness. Blood and m. Longissimus were collected in pigs at antemortem (30 days before slaughter) and postmortem periods. After slaughtered, carcass weight and backfat thickness were measured. Growth factors and hormones in serum and m. Longissimus were measured by radioimmunoassay or enzyme-linked imuunosorbent assay. Before antemortem period, serum IGF-I and -II concentrations were positively correlated with the carcass weight and backfat thickness in gilts, and the concentrations of TGF-β1 and cortisol in barrows show the correlation with only carcass weight. Also, the positive correlations of muscular IGFs and TGF-β1 at postmortem 45 min with the carcass weight and backfat thickness were detected. Consequently, these results suggest that the serum and muscular endocrine factors are involved in the carcass weight and backfat thickness in pigs.

The HANBIT device is a non axi-symmetric mirror being operated as a national users’ facility. Plasmas are routinely produced by ICRF at 3.5 MHz with a slot antenna with gas puffing and the line-int...

Alzheimer's disease (AD) is an irreversible and progressive neurodegenerative disorder. AD is the most common cause of dementia worldwide, and its incidence is increasing in line with population aging. The primary feature of AD is progressive cognitive decline, and severe AD is characterized by reduced communication skills and mobility. However, successful treatment can substantially improve quality of life. Donepezil is an acetylcholinesterase inhibitor approved for use across the full spectrum of mild, moderate, and severe AD. Donepezil has been available at doses of 5 or 10 mg once daily for more than a decade and, more recently, a single high once-daily sustained-release 23-mg dose has been approved for treatment of patients with moderate to severe AD. The rationale for the higher dose formulation was the expected increase in acetylcholinesterase inhibition given the dose-response relationship of donepezil, with the benefits of the higher dose being most apparent in patients with more advanced AD. Donepezil 5 and 10 mg/day have been well studied in mild-to-moderate AD, and a clinical trial has confirmed the benefits of donepezil 23 mg/day in patients with moderate to severe AD, particularly for language and visuospatial ability. This review presents an overview of the evidence for donepezil across the spectrum of AD, with a focus on dose optimization for disease progression.

In slim 2.5″ HDDs with 5mm or 7mm-height, the mechanical structure has to be simplified and all of the axial dimensions have to be miniaturized. It results in too flexible HDDs which is vulnerable to external force Especially, the rotating hub is so thin and flexible to make contact with stationary sleeve by clamping force. In this paper, we investigated the mechanical contact between the rotating hub and stationary sleeve of a 2.5″ HDD with 5 mm-height at low rotating speed. And we checked upper thrust surface in hub and sleeve after tearing down the FDBs. Circumferential scratch is observed on the upper thrust surface of sleeve and hub due to mechanical contact. Hub deflection due to disc clamping force was identified as a source of mechanical contact between rotating hub and stationary sleeve. To prevent mechanical contact between them, we proposed a robust design of hub and validated the proposed design theoretically and experimentally.

Diblock copolymers consisting of poly(N 5 -hydroxyalkylglutamine) (PHAG) and poly(N-isopropylacrylamide) (PNIPAAm) were prepared by aminolysis with aminoalkanols of the side-chain ester of poly(γ-benzyl L-glutamate) (PLBG) as a part of PBLG-PNIPAAm block copolymers. The molecular weight ratio of the initial PBLG to the resulting PHAG was nearly 0.35. The effect of PNIPAAm on the conformational change of PHAG in PHAG-PNIPAAm block copolymers with temperature was investigated by circular dichroism. Poly[N 5 -(2-hydroxyethyl)-L-glutamine] (PHEG) and the PHEG-PNIPAAm copolymer (GNE) stayed in a randomly coiled conformation whereas poly(N 5 -(3-hydroxypropyl)-L-glutamine] (PHPG), poly(N 5 -(4-hydroxybutyl)-L-glutamine) (PHBG), PHPG-PNIPAAm copolymer (GNP), and PHBG-PNIIPAm copolymer (GNB) underwent conformational transitions with temperature.The conformational change of the PHPG block in GNP copolymer occurred from an α-helix to a random coil after the incorporatoin of PNIPAAm into the copolymer. The thermodynamic parameters of the thermally induced helix-coil transition for PHBG and PHBG-PNIIPAm in aqueous solution were calculated.

To complete basic configuration for the RF heating scenario in Central Cell of the Hanbit mirror device, a RF amplifier system with a power of 100 kW and frequency range of 1.4 – 4.0 MHz, and a hig...

A Thomson scattering system on the Hanbit magnetic mirror device has been installed to measure the electron temperature and density of the plasma in the central cell. The configuration is based on a standard 90° scattering scheme. The optical system consists of a Q-switched Nd:YAG laser, input optics, collection optics, spectrograph optics, detectors, and a data acquisition system. Although the laser beam path is about 50 m long and the background emissions are not low, the electron temperature measurements have been made at a single point on a shot-by-shot basis, in which the stray light was considerably suppressed by using a beam dump, a viewing dump, and baffles. The measured electron temperature is about 50–70 eV in experiments for plasma production and heating by ICRF of 200-kW-rf power using a slot antenna. A description of the installed system and the experimental results are presented.

The first phase of the HANBIT project that started in 1996, is ending this year. The goal of the first phase is to establish a decent experimental facility based on the HANBIT mirror device and to ...

Poly(malonic ester) with two symmetrical azobenzene groups (PDR1) was synthesized, and azo dye-doped polymer (ADP) thin films were prepared using PDR1 and matrix polymers such as PMMA, PC, and PVK. All the ADP thin films were found to be suitable as reversible media for data storage and retrieval. The mechanism of the optical recording was a trans-cis isomerization of the azobenzene units by the irradiation of linearly polarized Ar laser and thermal process.

A frequency modulated interferometer is developed, which uses a 94 GHz Gunn oscillator and a single sideband (SSB) upconverter as a frequency modulator. An SSB upconverter makes it possible to use a heterodyne phase measurement technique with one mm-wave source. In addition, the influence of frequency drift and phase noise of a mm-wave source on the phase measurement can be reduced. In this work, the performance of a SSB upconverter as a frequency modulator is examined. Also, overall performance of the mm-wave interferometer with a SSB upconverter and line density measurement results in a mirror device are described.