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Understanding fundamental interactions of elementary particles is a long sought goal of nuclear physics study. Nuclear theorists recently estimated about 4000 nuclei are still unknown and their structures and reaction mechanisms need to be studied by both experiment and theory. The nuclear properties are also important to find the origin of elements in the Universe. The Center for Exotic Nuclear Studies (CENS) at the Institute for Basic Science was founded to address such fundamental problems in astrophysics and nuclear physics. In this paper, the latest research activities at CENS is highlighted and the status of experimental device developments performed by the center is reported.

A long-standing question in nuclear physics is whether chargeless nuclear systems can exist. To our knowledge, only neutron stars represent near-pure neutron systems, where neutrons are squeezed together by the gravitational force to very high densities. The experimental search for isolated multi-neutron systems has been an ongoing quest for several decades1, with a particular focus on the four-neutron system called the tetraneutron, resulting in only a few indications of its existence so far2–4, leaving the tetraneutron an elusive nuclear system for six decades. Here we report on the observation of a resonance-like structure near threshold in the four-neutron system that is consistent with a quasi-bound tetraneutron state existing for a very short time. The measured energy and width of this state provide a key benchmark for our understanding of the nuclear force. The use of an experimental approach based on a knockout reaction at large momentum transfer with a radioactive high-energy 8He beam was key.

Exotic nuclei are characterized by having a number of neutrons (or protons) in excess relative to stable nuclei. Their shell structure, which represents single-particle motion in a nucleus1,2, may vary due to nuclear force and excess neutrons3–6, in a phenomenon called shell evolution7. This effect could be counterbalanced by collective modes causing deformations of the nuclear surface8. Here, we study the interplay between shell evolution and shape deformation by focusing on the magnetic moment of an isomeric state of the neutron-rich nucleus 75Cu. We measure the magnetic moment using highly spin-controlled rare-isotope beams and achieve large spin alignment via a two-step reaction scheme9that incorporates an angular-momentum-selecting nucleon removal. By combining our experiments with numerical simulations of many-fermion correlations, we find that the low-lying states in 75Cu are, to a large extent, of single-particle nature on top of a correlated 74Ni core. We elucidate the crucial role of shell evolution even in the presence of the collective mode, and within the same framework we consider whether and how the double magicity of the 78Ni nucleus is restored, which is also of keen interest from the perspective of nucleosynthesis in explosive stellar processes.

In this work, we study the InP-InGaAs single photon avalanche diodes with multiple InGaAs quantum wells in the multiplication region for quantum information and communication. The compositions of InGaAs quantum wells are adjusted to give transition wavelength of 1.55. Simulation results show that three orders of magnitude improvement of dark count probability and an order of magnitude improvement of single photon quantum efficiency are expected with the adaption of multiple quantum-wells in the multiplication region. The improvement dark count probability is due to the difference of ionization coefficients for electrons and holes caused by the large difference between the conduction and valence band edge of multiple quantum-well layers inserted in the multiplication layer.

Objective:The local delivery of antimicrobials is attractive for a number of reasons. Chitosan, a biodegradable polysaccharide sponge material, has been proposed as medium to deliver antibiotics directly to wounds. In this report we evaluate the safety and practicality of antimicrobial delivery via chitosan sponge.Method:We present the clinical course and systemic absorption characteristics of three cases of people with diabetic foot wounds treated with antibiotic soaked chitosan sponge (Sentrex BioSponge, Bionova Medical, Germantown, TN). The antibiotic sponge was made by reconstituting 1.2g tobramycin or 100mg doxycycline in 10–15ml saline and saturating the sponge with the solution. The sponge was then applied to the wounds. Serum levels of each respective antibiotic were evaluated after application. Additional in vitrostudies were conducted evaluating elution of antibiotics from the chitosan sponge at established minimum inhibitory concentrations (MIC) for Staphylococcus aureusover 28 days.Results:No patient experienced adverse local or systemic effects due to the sponge treatment. The measured serum levels applied antibiotics remained far less than established minimums after intravenous therapy. Each patient required further treatment, however local infection or contamination resolved during the course of their hospital stay after the chitosan/antibiotic application.Conclusion:The use of antibiotic-impregnated chitosan sponges appears a safe and effective mechanism of local delivery of antimicrobials in wounds. Future studies and clinical trials are ongoing to confirm these results and to guide clinical applications.

The involvement of the nicotinamide adenine dinucleotide (NAD+) salvage pathway in cancer cell survival is poorly understood. Here we show that the NAD+salvage pathway modulates cancer cell survival through the rarely mutated tumour suppressor p73. Our data show that pharmacological inhibition or knockdown of nicotinamide phosphoribosyltransferase (NAMPT), a rate-limiting enzyme in the NAD+salvage pathway, enhances autophagy and decreases survival of cancer cells in a p53-independent manner. Such NAMPT inhibition stabilizes p73 independently of p53 through increased acetylation and decreased ubiquitination, resulting in enhanced autophagy and cell death. These effects of NAMPT inhibition can be effectively reversed using nicotinamide mononucleotide (NMN), the enzymatic product of NAMPT. Similarly, knockdown of p73 also decreases NAMPT inhibition-induced autophagy and cell death, whereas overexpression of p73 alone enhances these effects. We show that the breast cancer cell lines (MCF-7, MDA-MB-231 and MDA-MB-468) harbour significantly higher levels of NAMPT and lower levels of p73 than does the normal cell line (MCF-10A), and that NAMPT inhibition is cytotoxic exclusively to the cancer cells. Furthermore, data from 176 breast cancer patients demonstrate that higher levels of NAMPT and lower levels of p73 correlate with poorer patient survival, and that high-grade tumours have significantly higher NAMPT/p73 mRNA ratios. Therefore, the inverse relationship between NAMPT and p73 demonstrable in vitrois also reflected from the clinical data. Taken together, our studies reveal a new NAMPT-p73 nexus that likely has important implications for cancer diagnosis, prognosis and treatment.

Reovirus is a naturally oncolytic virus that preferentially replicates in Ras-transformed cells and is currently undergoing clinical trials as a cancer therapeutic. Ras transformation promotes reovirus oncolysis by enhancing virion disassembly during entry, viral progeny production, and virus release through apoptosis; however, the mechanism behind the latter is not well understood. Here, we show that reovirus alters the intracellular location of oncogenic Ras to induce apoptosis of H-RasV12-transformed fibroblasts. Reovirus infection decreases Ras palmitoylation levels and causes accumulation of Ras in the Golgi through Golgi fragmentation. With the Golgi being the site of Ras palmitoylation, treatment of target cells with the palmitoylation inhibitor, 2-bromopalmitate (2BP), prompts a greater accumulation of H-RasV12 in the Golgi, and a dose-dependent increase in progeny virus release and subsequent spread. Conversely, tethering H-RasV12 to the plasma membrane (thereby preventing its movement to the Golgi) allows for efficient virus production, but results in basal levels of reovirus-induced cell death. Analysis of Ras downstream signaling reveals that cells expressing cycling H-RasV12 have elevated levels of phosphorylated JNK (c-Jun N-terminal kinase), and that Ras retained at the Golgi body by 2BP increases activation of the MEKK1/MKK4/JNK signaling pathway to promote cell death. Collectively, our data suggest that reovirus induces Golgi fragmentation of target cells, and the subsequent accumulation of oncogenic Ras in the Golgi body initiates apoptotic signaling events required for virus release and spread.

An elliptic cylindrical omnidirectional light absorber forming a pseudo-optical black hole is studied both analytically and numerically. The conditions for permittivity tensors to trap optical rays are obtained from semiclassical analysis of the ray optic Hamiltonian. The dispersive finite-difference time-domain method is used to study the performance of these light-absorbing structures numerically. It is found that the permittivity of the structure in the form (1/sinh^u u)≥(a/r)^n traps the light ray efficiently into the elliptic absorber for n≥2, where u is the radial elliptic coordinate and a is the focal distance.

Pathologically confirmed microscopic extrathyroidal extension (ETE) is often identified after hemithyroidectomy in patients with papillary thyroid microcarcinoma (PTMC). Without the presence of microscopic ETE, these patients would be optimal candidates for hemithyroidectomy. The present study aimed at evaluating the clinical impact of microscopic ETE on the recurrence of PTMC treated with hemithyroidectomy. We compared the clinicopathological characteristics and 5-year outcomes for 262 PTMC patients without ETE and 86 with microscopic ETE who were treated with hemithyroidectomy between January 2004 and December 2010. The mean tumour size was larger (0.67 vs. 0.54 cm, p< 0.001) and the proportion of tumours measuring =0.5 cm was higher (84.9 vs. 66.8 %, p= 0.001) in patients with microscopic ETE as compared with patients without ETE. Occult multifocal disease was more frequent in patients with microscopic ETE than in those without ETE (14.0 vs. 6.5 %, p= 0.030). However, the recurrence rate was not different between the two groups during the mean 55.8-month follow-up period. In addition, univariate and multivariate analyses revealed no meaningful association between recurrence and microscopic ETE in patients with PTMC treated with hemithyroidectomy. Although microscopic ETE was associated with large tumour size and multifocal disease, its clinical impact on disease recurrence was not significant in PTMC patients treated with hemithyroidectomy. Therefore, microscopic ETE identified after hemithyroidectomy would not be an absolute indication for completion thyroidectomy in patients with PTMC.

Using the Deutsch model of closed timelike curves,- we show that a universal doner can be constructed that when acting on a completely arbitrary qubit state, exceeds the no-cloning bound for fidelity. Since the no-cloning theorem has played a central role in the development of quantum information science, it is clear that the existence of closed timelike curves that behave according to Deutsch's model would radically change the rules for quantum information technology. Nevertheless, we show that this type of cloning does not violate no-signaling criteria. [ABSTRACT FROM AUTHOR]

A measurement system is presented for evaluating the characteristics of both sides of an LED wafer usingelectroluminescence (EL). Integrating spheres (IS), photodiodes, pico-ammeters, spectrometers were installed in the frontand rear sides to measure optical characteristics with minimum EL loss. A probe was connected to a source meter with athin wire and attached using a transparent fixture in the front IS. The EL characteristics in a measuring point were peakwavelength, FWHM (full width at half maximum), forward current, forward voltage and reverse current. EL images werecreated by combining the motion of a stage and the EL characteristics. The correlation between the EL and the chip-leveltests and the repeatability test showed that the dual measurement is useful for LED manufacturing. Our patents wereapplied to install the probe and create the EL image.

Sausages with different fat contents (16 or 29%) were purchased from local stores, vacuum-packaged in oxygen-impermeable bags, and irradiated at 0 or 5 kGy using a linear accelerator. The changes in quality attributes of irradiated sausages were determined during storage at 4°C. The 2-thiobarbituric acid-reactive substance values of sausages were not affected by fat content but were increased after irradiation (5 kGy). Storage for 60 d increased the 2-thiobarbituric acid-reactive substance values of nonirradiated sausages (P< 0.05) but had no effect on irradiated sausages. The numbers of volatile compounds and the amounts of total volatiles were increased by irradiation in both the high-fat (29% fat) and low-fat (16% fat) sausages. Dimethyl sulfide was detected only in irradiated sausages, regardless of fat content (P< 0.05), but it disappeared after 60 d of storage. Pentane and 1-heptene were detected only in irradiated samples after 60 d of storage. Low-fat sausages had greater L* values, but had lesser a* and b* values than high-fat sausages. Irradiation and storage had little effect on either the exterior or interior color (L*, a*, and b* values) of sausages. Fat content had no effect on the sensory variables of sausages, regardless of irradiation and storage. However, irradiated sausages had significantly stronger off-odors and off-flavors than nonirradiated sausages regardless of fat content (P< 0.05). This indicated that fat content in sausages had a minimal effect on the quality of irradiated sausages during storage.

Abstract: A dispersive full-wave finite-difference time-domain (FDTD) model is used to calculate the performance of elliptic cylindrical cloaking devices. The permittivity and the permeability tensors for the cloaking structure are derived by using an effective medium approach in general relativity. The elliptic cylindrical invisibility devices are found to show imperfect cloaking, and the cloaking performance is found to depend on the polarization of the incident waves, the direction of the propagation of those waves, the semi-focal distances and the loss tangents of the meta-material. When the semi-focal distance of the elliptic cylinder decreases, the performance of the cloaking becomes very good, with neither noticeable scatterings nor field penetrations. For a larger semi-focal distance, only the TM wave with a specific propagation direction shows good cloaking performance. Realistic cloaking materials with loss still show a cloak that is working, but attenuated back-scattering waves exist.

To prevent oxidative quality changes, a few selected antioxidants, ascorbic acid, or an ascorbic acid plus α-tocopherol combination were electrostatically sprayed on the surface of ground beef patties. Color, metmyoglobin, oxidation-reduction potential, lipid oxidation, and volatiles of the samples were determined during the 8 d of aerobic storage. Spraying of ascorbic acid at 500 mg/kg was the most effective in controlling discoloration of ground beef. Spraying of ascorbic acid at 500 mg/kg was also effective in reducing 2-thiobarbituric acid-reactive substances and volatile aldehydes such as hexanal and heptanal related to lipid oxidation. Spraying of phenolic antioxidants such as tocopherol, sesamol, or rosemary oleoresin showed significant (P< 0.05) antioxidant effects, but had no effects (P< 0.05) in stabilizing the color of ground beef. Sesamol at 100 mg/kg showed the most potent antioxidant activities among the antioxidants, and its antioxidant effect was as strong as that of 500 mg/kg of ascorbic acid. It was concluded that electrostatic spray of ascorbic acid on the surface of ground beef at 500 mg/kg was an efficient and economical way to prevent both lipid oxidation and color changes in ground beef.

The objective of this paper is to manufacture a thermal management mould with three different materials and conformal cooling channels using a laser-aided direct metal tooling process to obtain both rapid and uniform cooling characteristics. The geometry of the thermal management mould is decomposed into three parts, including a moulding part consisting of P21 injection tool steel, a mid-layer consisting of Monel 400 material, and a base part consisting of Ampcoloy 940 material, according to the functionality of each part. The base part is designed as a heat sink and the midlayer is adopted to reduce the thermal stress in the joined regions. In this paper, the features of the design and a rapid tooling process for the thermal management mould as well as the characteristics of the mould are discussed. Several injection-moulding experiments are performed to investigate the practical applicability of the fabricated mould and the effects of the cooling time on the quality of the moulded product. The results of the experiments show that the cooling time of the thermal management mould can be shortened to 3 s. Through comparison of the product from the thermal management mould with that of a previously designed mould, it is shown that the designed mould can improve both the cycle time and the quality of the product.

This study investigates the effects of stoichiometry, humidity, cell temperature, and pressure on the performance and the flooding of the proton exchange membrane fuel cell. Values of stoichiometry are 1.5, 2.0, and 2.5 at cell temperatures of 50, 55, and 60 °C, respectively. This study shows that the dimensionless flooding value (FV) is a function of the stoichiometry, humidity, temperature, and pressure. The FV is calculated by using the measured values of temperature, humidity, pressure, and flowrate of the cathode. The effect of the dimensionless number on the flooding of the cathode in the proton exchange membrane fuel cell is analysed in this study. The effects of air stoichiometry, cell temperature, and air humidity are also discussed in this article.

The effects of dietary crude glycerin on growth performance, carcass characteristics, meat quality indices, and tissue histology in growing pigs were determined in a 138-d feeding trial. Crude glycerin utilized in the trial contained 84.51% glycerin, 11.95% water, 2.91% sodium chloride, and 0.32% methanol. Eight days postweaning, 96 pigs (48 barrows and 48 gilts, average BW of 7.9 ± 0.4 kg) were allotted to 24 pens (4 pigs/pen), with sex and BW balanced at the start of the experiment. Dietary treatments were 0, 5, and 10% crude glycerin inclusion in corn-soybean meal-based diets and were randomly assigned to pens. Diets were offered ad libitum in meal form and formulated to be equal in ME, sodium, chloride, and Lys, with other AA balanced on an ideal AA basis. Pigs and feeders were weighed every other week to determine ADG, ADFI, and G:F. At the end of the trial, all pigs were scanned using real-time ultrasound and subsequently slaughtered at a commercial abattoir. Blood samples were collected pretransport and at the time of slaughter for plasma metabolite analysis. In addition, kidney, liver, and eye tissues were collected for subsequent examination for lesions characteristic of methanol toxicity. After an overnight chilling of the carcass, loins were removed for meat quality, sensory evaluation, and fatty acid profile analysis. Pig growth, feed intake, and G:F were not affected by dietary treatment. Dietary treatment did not affect 10th-rib backfat, LM area, percent fat free lean, meat quality, or sensory evaluation. Loin ultimate pH was increased (P= 0.06) in pigs fed the 5 and 10% crude glycerin compared with pigs fed no crude glycerin (5.65 and 5.65 versus 5.57, respectively). Fatty acid profile of the LM was slightly changed by diet with the LM from pigs fed 10% crude glycerin having less linoleic acid (P< 0.01) and more eicosapentaenoic acid (P= 0.02) than pigs fed the 0 or 5% crude glycerin diets. Dietary treatment did not affect blood metabolites or frequency of lesions in the examined tissues. This experiment demonstrated that pigs can be fed up to 10% crude glycerin with no effect on pig performance, carcass composition, meat quality, or lesion scores.

The colorimetric stability upon thermal stress of a series of conjugated polymer supramolecules prepared from 10,12‐docosadiyndioic acid (DCDDA)‐derived diacetylene monomers has been explored. Polydiacetylenes obtained from DCDDA‐bis‐mBzA 3, containing m‐carboxyphenylanilido groups at the both ends of the monomer, were observed to be highly colorimetrically stable upon thermal stimulation. The blue color of a solution containing these polydiacetylene vesicles remains unchanged even when the vesicles were subjected to boiling water. The unusual colorimetric stability is further demonstrated by the observation that blue color persists until vesicles in ethylene glycol are heated to 140 °C. The nature of this unusual thermal stability was elucidated by using polydiacetylene supramolecules, prepared from analogs of DCDDA‐bis‐mBzA 3. The presence of internal amide groups as well as aromatic interactions was found to be essential for the high colorimetric stability of the polydiacetylene supramolecules.

PDA(Polydiacetylene)-supramolecules were successfully immobilized on the surface of Sc2O3/GaN/Sapphire structures for use as selective NH3 gas sensors. The Sc2O3 was epitaxially grown on GaN/Sapphire templates by molecular beam epitaxy (MBE) to replace the non-uniform native Ga2O3. The GaN-based PDA gas sensors showed excellent selectivity for ammonia detection after the end-functional group was modified to respond to this specific gas species. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

In order to develop more user‐viable formats for polydiacetylene (PDA) biosensors, it is necessary to control the biochemical and physical properties of the PDA matrix. In this study, we prepare polydiacetylene liposomes from controlled mixtures of 10,12‐pentacosadiynoic acid (PCDA) and PCDA–MI, a PCDA derivative with a maleimide headgroup. Both the chemical and physical properties of the liposome are easily manipulated by controlling the molar ratio of PCDA to PCDA–MI during liposome preparation. After preparing the liposomes, the activity of the maleimide headgroups increases linearly with the PCDA–MI content for concentrations in the range of 0–30 %. As a result, the antibody‐binding characteristics of the PDA liposomes increase with PCDA–MI content. It is also possible to modulate the physical properties of the liposome. Differential scanning calorimetry measurements show that the phase organization of the liposome is progressively lost with increasing PCDA–MI content. Furthermore, the liposomes show an increased color change in response to temperature that is also dependent on PCDA–MI content, indicating increased membrane fluidity. When PCDA:PCDA–MI liposomes are conjugated with a cell‐specific antibody the response to the antigen induces a color change that is dependent on the PCDA–MI content. Consequently, it is deduced that the increased sensitivity of the liposomes containing higher PCDA‐MI content is due to increased antibody binding and membrane fluidity. From these experiments, we identify the factors controlling the colorimetric properties of the PDA matrix and demonstrate that it is possible to modulate the sensitivity and stability of PDA biosensors by controlling the ratio of constituent monomers.

Poly(vinyl alcohol) (PVA) films embedded with functional polydiacetylene (PDA) are efficiently prepared for color and fluorescence imaging. Intensely blue films are obtained by mixing and drying solutions containing PDA vesicles and PVA. A blue‐to‐red color transition is observed upon heating the polymer films. In addition, selective UV irradiation (through a photomask) of PVA films containing diacetylene monomer results in the generation of micropatterned color (without heating) and both color and fluorescent images (after heating the films at 120 °C for 10 s). Patterned two‐color (blue and red) images in the polymer film are readily obtained by a sequential process of photomasked irradiation, heating, and unmasked irradiation.

Perpendicularly arrayed and size‐controlled nanocylinders have been prepared by simply blending an asymmetric polystyrene‐block‐polyisoprene‐block‐polystyrene triblock copolymer with polystyrene (the minority component) homopolymers of different molecular weights. The preference for perpendicular orientation or hexagonal ordering of the nanocylinders over a large area in the asymmetric block copolymer can be controlled by adjusting the molecular weight of the blended homopolymer, and the perfection of hexagonal ordering of the perpendicular cylinders can be tuned by using a substrate whose surface tension is much different from that of the majority component of the block copolymer. Such highly controlled nanostructured block‐copolymer materials, which have been obtained by a simple method independent of film thickness and interfacial tension between the blocks and the substrates, have wide‐ranging commercial potential, e.g., for use in membranes and nanotemplates with size‐tunable pores, bandgap‐controlled photonic crystals, and other nanotechnological fields demanding a specific nanosize and nanomorphology.

The colorimetric reversibility of polydiacetylene supramolecules, derived from a variety of functionalized diacetylenic lipids, has been subjected to detailed investigation. In an earlier effort, it was shown that polydiacetylene vesicles prepared from PCDA-mBzA 1, bearing terminal m-carboxyphenylamido groups, display complete reversibility upon thermal stimulation [J. Am. Chem. Soc. 2003, 125, 8976]. The origin and nature of reversible thermochromism in these systems have been elucidated in-situ in the current studies by using polydiacetylene supramolecules, prepared from analogues of PCDA-mBzA 1. Issues related to the effects of (1) internal amide groups, (2) headgroup aromatic interactions, (3) lengths of the hydrophobic alkyl chains, and (4) terminal carboxylic groups on the colorimetric reversibility of the polydiacetylene supramolecules have been probed. The results demonstrate that well-developed hydrogen-bonding and aromatic interactions between headgroups are essential for complete recovery of the length of the conjugated π-electron chain following thermal stimulus. The results of this comprehensive investigation allow for the first time the rational design of reversible colorimetric sensors based on polydiacetylene supramolecules.

The purpose of this study was to obtain detailed quantitative information on all cell types in the testis interstitium of Korean ring-necked pheasants and to combine these data with changes in the steroidogenic function of the testis during the breeding and non-breeding seasons. For animals collected during the breeding season, their testis weights, sperm production, serum testosterone levels and leuteinizing hormone (LH)-stimulated testosterone secretion were significantly (p< 0.01) increased compared to the non-breeding season. Testes of the pheasants during the non-breeding season displayed a 98% reduction in testis volume that was associated with a decrease in the absolute volume of seminiferous tubules (98% reduction), tubular lumen (100%), interstitium (90%), blood vessels (84%), lymphatic spaces (97%), Leydig cells (79%), mesenchymal cells (51%) and myoid cells (61%) compared to the breeding season. The numbers of Leydig cells, mesenchymal cells and myoid cells per testis in the breeding season were much higher than in the non-breeding season. Although the mean volume of a Leydig cell was 74% lower in the non-breeding season, the mean volumes of myoid and mesenchymal cells remained unchanged. These results demonstrate that there are striking differences in the testicular structure of the Korean ring-necked pheasant during the breeding and non-breeding seasons. Every structural parameter of the Leydig cell was positively correlated with both testosterone serum levels and LH-stimulated testosterone secretion. The correlation of changes in hormonal status with the morphometric alterations of Leydig cells suggests that the Korean-ring necked pheasant may be used as a model to study structure-function relationships in the avian testis.

A prototype TSV (Tritide Storage Vessel) has been manufactured for the long-term storage of tritium of the WTRF (Wolsong Tritium Removal Facility). A performance test was carried out to demonstrate that the TSV could hold a minimum of 500kCi of tritium. This experiment was conducted by a batch type hydriding reaction. Hydrogen gas equivalent to 50kCi of tritium was reacted with the titanium sponge in a batch reaction. Experimental results for 10 batches show that the TSV has enough capacity to store 500kCi of tritium.

To better understand the effects of interfacial molecular orientation on adhesion to plastics, the interfaces between poly(ethylene terephthalate) (PET) and different silane coupling agents were probed using sum frequency generation (SFG) vibrational spectroscopy. The polymer/air interface was dominated by the ester carbonyl, methylene, and phenyl groups. Upon contacting the PET film with the amino-functional silane 3-aminopropyltrimethoxysilane (ATMS), the ester carbonyl stretch shifted to a lower energy indicating the formation of hydrogen bonds between the polymer surface and the silane molecules. This shift was not observed when silanes that contained no hydrogen bond donors, such as (3-glycidoxypropyl)trimethoxysilane and n-butyltrimethoxysilane, were placed into contact with the PET surface. Further evidence of silane ordering at the interface was observed as vibrational peaks attributed to the C−H stretching of the silane methoxy headgroups dominated the PET/silane spectra. It was determined that the conformation of the ATMS molecules at the interface was such that the amino endgroups were oriented toward the interface while the methoxy headgroups were directed toward the silane bulk.

High-performance thin-film LiCoO2 cathodes were successfully fabricated by aluminum-oxide coating. Both the galvanostatic charge−discharge experiments and the cyclic voltammograms (CVs) showed enhanced electrochemical properties in the Al2O3-coated LiCoO2 films compared to those in the uncoated ones. The improved cycling behaviors in the coated samples are caused by the suppression of cobalt dissolution from the LiCoO2 thin films, with the formation of an aluminum-oxide solid electrolyte residing between the LiCoO2 cathode and liquid electrolyte. Galvanostatic intermittent titration technique (GITT) results clearly showed that the Al2O3-coated samples had higher Li diffusivities than the uncoated ones after 80 cycles. The effect of Al2O3 thickness on the electrochemical properties up to 300 nm was also studied.

Calculations are presented for the ortho- and para-substituted phenol−H2O complexes. A variety of conformers are predicted, and their relative energies are compared. Binding energies of the complexes are computed, and detailed analysis is presented on the effects of substitution on the strength of the hydrogen bonding in the complexes. F- and Cl- (NH2- and OH-) substituted complexes are studied to analyze the effects of electron-withdrawing (electron-donating) groups. In para-substituted complexes, the electrostatic (inductive and resonance) effects influence the binding energies in opposite fashion, depending on whether the hydroxyl group is proton-donating or -accepting. The binding energy of the complex increases (decreases) by the electron-withdrawing substituent when the phenolic OH group is proton-donating (-accepting), and the reverse is true for the electron-donating substituents. For ortho-substituted complexes, direct involvement of the substituting group and the geometry change of the hydrogen bond should be invoked to elucidate the complicated pattern of the binding energy of the complexes. We also suggest that the frequency of the phenolic OH stretching mode of the complex may help elucidate the role of the OH group, determining whether the OH group is proton-donating or -accepting.

We report that entangled pairs of quantum clocks (non-degenerate quantum bits) can be used as a specialized detector for precisely measuring difference of proper-times that each constituent quantum clock experiences. We describe why the proposed scheme would be more precise in the measurement of proper-time difference than a scheme of two-separate-quantum-clocks. We consider possibilities that the proposed scheme can be used in precision test of the relativity theory.

ABSTRACTA TRF (Tritium Removal Facility) will be constructed at Wolsong Nuclear Generating station to remove the tritium from heavy water. Titanium sponge has been selected as suitable material for tritium product immobilization. This paper is a summary of the experimental results conducted for the various properties of the reaction between titanium sponge and hydrogen isotopes. The conditions for activation, hydriding and dehydriding were investigated. The factors such as initial gas pressure and the helium content in the gas stream influencing the hydriding rate of the bed were examined.

ABSTRACTAn overview of the tritium related research and activities presently undertaken in Korea is presented. These activities encompass the Wolsong Tritium Removal Facility (WTRF) in KHNP, isotope separation, storage and biology in KAERI, KEPRI and KAIST. The design status of the WTRF that serves four CANDU reactors is described. It is made up of three parts; liquid phase catalytic exchange (LPCE), cryogenic distillation, and metal hydride storage. Results from the technological R&D of tritium processing for the WTRF and biology are summarized.

The effects of molecular weight and acrylic acid content on the adhesive properties of a series of monodisperse poly(n-butyl acrylate) materials have been investigated. The short-time adhesion, or “tackiness”, of these model pressure-sensitive adhesives was quantified by performing probe-tack experiments. These experiments consist of a bonding phase, where a flat punch is brought into contact with a PnBA layer, and a subsequent debonding phase, where the probe is pulled away from the surface. The debonding process was separated into three distinct deformation mechanisms:  (1) the appearance of cavities throughout the adhesive layer; (2) lateral growth of these cavities within the plane of the adhesive layer; (3) the formation and eventual failure of a fibrillar structure as the adhesive is extended in the direction of the applied tensile load. Cavitation depends primarily on the elastic character of the adhesive, but the lateral cavity growth and extensional mechanisms are strongly affected by the ability of the adhesive to flow during the time scale of the experiment. The nature of these processes was determined by an effective Deborah number, defined as the terminal relaxation time of the polymer multiplied by the initial strain rate imposed during the debonding process.

Fluoro-terminated hyperbranched poly(ether ketone)s (FHBPEKs) with controlled degrees of branching and their linear analogous poly(ether ketone) (LPEK) whose chemical structure and molecular weights were similar to those of FHBPEKs were synthesized and characterized. Depending on the amount of the core molecules, degrees of branching of 0.49 (FHBPEK), 0.62 (FHBPEK−CM01), and 0.67 (FHBPEK−CM02) could be obtained with little variation in the number-average molecular weights of the three FHBPEKs. From the dynamic mechanical analyses, it was investigated that the crossover of the storage modulus G‘(ω) and the loss modulus G‘ ‘(ω) started to disappear at a critical value (> 0.62−0.67) of the degree of branching, indicating a nearly Newtonian or little entanglement flow. The correlation time, τc, was determined from the shear relaxation moduli and the Cole−Davidson equation, which provided a unique means to evaluate the melt processability on the basis of the molecular mobility. Highly branched structure of FHBPEKs predominantly increased the molecular mobility and enhanced the melt processability, realizing the optimum processing temperature lowered by 52−72 °C depending on the degree of branching, compared to that of LPEK. Further insights into the correlation times with the Vogel−Tamman−Fulcher (VTF) equation and the Arrhenius equation provided some novel information about the temperature dependence of the molecular mobility and the activation energy, in conjunction with the processability and the fragility of the FHBPEKs in comparison to the LPEK.