Similarity study of ROSA-III and fist large break cuonterpart tests to BWR large break LOCA

A large break test in a recirculation pump suction line with the assumption of LPCI-diesel generator failure was conducted at the ROSA-III test facility of Japan Atomic Energy Research Institute. A counterpart test was also performed at the FIST test facility of General Electric Company. The objective of the tests was to develop common understanding and interpretation of the controlling thermal-hydraulic phenomena during a large break LOCA of a BWR. The fundamental thermal-hydraulic phenomena in the ROSA-III and FIST tests such as the system pressure, mixture level and fuel rod surface temperatures agreed well. The FIST test had more bundle uncovery than that in ROSA-III since lower plenum steam in the FIST test flowed out of the jet pumps when they uncovered allowing more liquid to drain from the bundle. The ROSA-III and FIST tests and a BWR counterpart were analyzed with the RELAP5/MODI (cycle 018) code. The similarity of the ROSA-III and FIST large break tests to a BWR large break LOCA has been confirmed through comparison of calculated results though they are slightly different in details. It is perhaps desirable to reexamine the DNB and interphase drag correlations and the jet pump models usedin the code.     

Considering impacts and requirements for better understanding of environment interactions in home network services

A home network system (HNS) coordinates various networked home appliances to achieve value-added services. If multiple services are executed at the same time, functional conflicts between the home appliances may occur. These are known as feature interactions (FIs) in the HNS. We have previously defined two kinds of FIs: appliance interactions and environment interactions. Environment interaction refers to an indirect conflict of different appliances in the home environment, which is generally more difficult to capture than appliance interaction. Due to a lack of an amount of environmental impacts and requirements to be satisfied, the previous definition missed some obvious environment interactions, or mis-detected many acceptable cases.     

Reflection loss analysis by optical modeling of PV module

As an evaluation method of the photovoltaic (PV) system, it is necessary to clarify loss factor which decreases system efficiency. One of the factors mentioned is the reflection loss that depends on an incident angle. It is believed that the factor is simulated by reflections and transmissions in a module. Using the optical performance of a four-layer encapsulation, a simulation was made on the reflection loss according to Fresnel's law. Further, the incident angle modification factor as the coefficient for evaluating energetic reflection loss was described by a computer program simulation. The result was that the modification factor is between 0.96 and 0.98. Consequently, to obtain the optical property of module materials, the module tilt angle and its latitude location, the simulation could give the evaluation of annual reflection losses by such a factor at various regions.     

Dynamic viscoelastic properties of collagen gels with high mechanical strength

We developed a new method for the preparation of mechanically strong collagen gels by combining successively basic gel formation, followed by 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC) cross-linking and lyophilization. Gels cross-linked three times with this method showed stronger mechanical properties (G′: 3730 ± 2060 Pa, G″: 288 ± 35 Pa) than a conventional gel that was sequentially cross-linked with EDC once (G′: 226 ± 70 Pa, G″: 21 ± 4.4 Pa), but not as strong as the same gel with heating for 30 min at 80 °C (G′: 7010 ± 830 Pa, G″: 288 ± 35 Pa) reported in our previous paper. The conventional collagen gel was cross-linked with EDC once, heated once, and then subjected twice to a lyophilization–gel formation–cross-linking cycle to give three-cycled gel 2. This gel had the strongest mechanical properties (G′: 40,200 ± 18,000 Pa, G″: 3090 ± 1400 Pa, Young's modulus: 0.197 ± 0.069 MPa) of the gels tested. These promising results suggest possible applications of the gels as scaffolds in tissue engineering research.     

A positive type alkaline developable thermally stable and photosensitive polymer based on partially O-methylated poly(2,6-dihydroxy-1,5-naphthylene), an acidolytic de-cross-linker, and a photoacid generator

A positive working and chemically amplified photosensitive polymer based on partially (30%) O-methylated poly(2,6-dihydroxy-1,5-naphthylene) [PMPDHN (30)], 1,3,5-tris[(2-vinyloxy)ethoxy]benzene (TVEB) as an acidolytic de-cross-linker, and a photoacid generator (5-propylsulfonyloxyimino-5H-thiophen-2-ylidene)-(2-methylphenyl)acetonitrile (PTMA) has been developed. Poly(2,6-dihydroxy-1,5-naphthylene) (PDHN) with a number-average molecular weight of 33,000 was prepared by oxidative coupling polymerization of 2,6-dihydroxynaphthalene (2,6-DHN) using di-μ-hydroxo-bis-[(N,N,N′,N′-tetramethylethylenediamine)copper(II)] chloride [CuCl(OH)TMEDA] as the catalyst in 2-methoxyethanol at room temperature. PDHN was converted to PMPDHN by treating with iodomethane. The resist showed a sensitivity of 19.4 mJ cm⁻² and a contrast of 7.5 when it was exposed to 436 nm light, followed by post-baking at 120 °C for 5 min and developing with 2.38 wt% aqueous tetramethylammonium hydroxide (TMAH) solution at 25 °C. A fine positive image featuring 6 μm line and space patterns was obtained on the film exposed to 20 mJ cm⁻² of UV-light at 436 nm by the contact-printed mode. The optically estimated dielectric constants (at 1 MHz) of PMPDHN (30) with and without TVEB and PTMA are 3.03 and 3.01, respectively. The moisture absorption (1.7 wt%) of the resist system based on PMPDHN (30) and TVEB is very low compared to that (4.3%) of the resist system consisting of PDHN and 4,4′-methylenebis[2,6-bis(hydroxymethyl)]phenol (MBHP).     

Atrial natriuretic peptide enhances recovery from ischemia/reperfusion-induced renal injury in rats

Recovery from ischemic acute kidney injury requires the replacement of damaged tubular cells. This repair process involves epidermal growth factor (EGF) synthesized in medullary the thick ascending limbs (mTAL) of Henle. Atrial natriuretic peptide (ANP), a hormone synthesized by the cardiac atria, increases glomerular filtration rate and renal medullary blood flow. However, the effects of ANP on renal recovery after I/R-induced renal injury remain unclear. We therefore examined whether human ANP enhances recovery from I/R-induced renal injury by reducing damage to EGF-producing kidney cells in a rat model. Male Wistar rats weighing 200–240 g were observed for 48 h after reperfusion following 45-min renal ischemia. Rats were intravenously administered α-human ANP (α-hANP) at 0.2 μg/kg/min beginning immediately after ischemia and continuing for 2 h after reperfusion. Outer medullary blood flow (OMBF), EGF mRNA, serum blood urea nitrogen (BUN) and creatinine levels as indicators of glomerular function were measured, while urinary N-acetyl β-d-glucosaminidase (NAG) was used as a specific indicator of proximal tubular function. OMBF was increased by α-hANP after reperfusion and maintained significantly higher mRNA level of EGF in the kidney 24 h after reperfusion. I/R-induced increases in serum concentrations of BUN and creatinine and urinary concentrations of NAG were also reduced by α-hANP, with improved histopathological changes, including acute tubular necrosis at 24–48 h after reperfusion. This report is the first to demonstrate that α-hANP accelerates recovery following renal ischemic insult by reducing the damage to EGF-producing kidney cells.     

Incorporation of 2'-deoxy-2'-isonucleoside 5'-triphosphates (iNTPs) into DNA by A- and B-family DNA polymerases with different recognition mechanisms

Recently, α-L-threofuranosyl nucleoside 3'-triphosphates (tNTPs) have been reported to be incorporated into DNA by DNA polymerases. Isonucleosides especially the 2'-deoxy-2'-isonucleosides, would be considered regioisomers of α-L-threofuranosyl nucleosides. Therefore, we investigated the synthesis of 2'-deoxy-2'-isonucleoside 5'-triphosphates (iNTPs) having the four natural nucleobases and their incorporation into primer-template duplexes consisting of oligonucleotides containing natural 2'-deoxyribonucleosides and 2'-deoxy-2'-isonucleosides by using primer-extension reactions. We found that Klenow fragment (exo-; an A-family DNA polymerase) has strict recognition of the shape of nucleoside 5'-triphosphates and Therminator (a B-family DNA polymerase) has strict recognition of the shape of primer-template complexes, especially two base pairs upstream of the primer 3' terminus.     

Synthesis,Crystal and Local Electronic Structures,and Photoluminescence Properties of Red-Emitting CaAlzSiN2+z:Eu2+ with Orthorhombic Structure

Orthorhombic Ca_1−xEu_xAl_zSiN_2+z polycrystalline powders have been synthesized by a solid-state reaction at high temperature in a nitrogen atmosphere. The smaller lattice parameters compared with the single crystal and charge distribution analysis indicate that impure oxygen might be incorporated into the lattice. Ca_1−xEu_xAl_zSiN_2+z shows red emission at about 630 nm due to the transition of 4f⁶5d¹→4f⁷ when excited within 375–450 nm. With an increase in the Eu²⁺ concentration and z, the quantum efficiency of Ca_1−xEu_xAl_zSiN_2+z was significantly decreased due to concentration quenching and high photoionization. First-principle molecular orbital calculations suggest that the overall luminescence of Eu²⁺ may be mainly originated from the small Eu(1) center. CaSiN₂:Eu²⁺ is a potential red conversion phosphor for white LED applications.     

Cyclic voltammetry of lipophilic compounds in oil: Direct determination of lipid peroxide with a carbon past electrode

In preliminary experiments, we demonstrated that a cyclic voltammogram of a lipophilic compound can be conveniently obtained with the past electrode that was made from graphite powder and an oil in which the compound is dissolved. This finding was applied to the direct determination of lipid peroxides. Oxygenation of lipids at 120°C was followed by the cathodic current created by the reduction of the peroxides. The validity of the method was investigated by comparison with conventional methods (peroxide value, thiobarbituric acid, and weight gain). The amount of peroxides in an oil and its cathodic current show a linear relation in the initial stages of peroxidation (ca. 12 h). This electrochemical method was applied successfully to the evaluation of the antioxidant activity of butylated hydroxytoluene in linseed oil.