[en] Fatigue crack growth tests were carried out using CT specimen under the conditions of stress ratio R=0.1, 0.3, 0.5 for imported maraging steel(VAR), domestic maraging steel(ESR) and AISI4337-V steel. The near-threshold values, stable crack growth chracteristics and the behavior of crack closure were investigated. In the region of near-threshold fatigue crack growth, ΔKth decrease sharply from stress ratio R=0.1 to R=0.3 gradually over stress ratio R=0.3. Constant m increase and constants C decrease under increasing stress ratio respectively. And the gradient of fatigue crack growth rate decrease in the order of AISI 4337-V steel, ERS and VAR in the region of stable fatigue crack growth. If fatigue crack growth rate are evaluated by using ΔKeff which are calculated at the crack closure point, da/dN fits with one stright line independently of stress ratio. And the effective stress intensity factor range ratio U is the function of only Kmax.(Author)

[en] Through research facility stable operational management of RI-Biomics Center area academic-industrial support, authentication of state laboratory management, balanced regional development through tours and public relations, provide reliable data and phase establishment, general public receptivity growth and to support the smooth work of the national nuclear long-term business and other contract research project leads to advancement of national radiation induced fusion technology (RT) industry. 'Nuclear Advanced Technology Research Center' connect its business by RI-Biomics technical information provided for the purpose of issue papers, Watch Report, WCI Newsletter and distributed brochures. We provided the information, data, and technology solving the difficulties relationship of the small businesses and academic-industrial. Educational RI-Biomics technology theory and internship training was provided to the student intern for the practical skills and professional competency. For the purpose of stable operation of analysis instrumentation was performed the work, such as the writing of SOP. Plans to take the next GLP certified led

[en] The antidepressant desipramine (DMI) and its principal metabolite 2-hydroxydesipramine (HDMI) have been radiolabeled with ¹¹C for PET studies. The normethyl precursors of DMI and HDMI were synthesized from iminodibenzyl in 35% and 11% overall yield, respectively. Direct methylation of the normethyl precursor with [¹¹C]CH₃I, followed by HPLC purification, provided [¹¹C]DMI and [¹¹]HDMI in 18-30% and 15-23% decay-corrected radiochemical yields, respectively, in a 45 min synthesis time from end of bombardment. The specific activities of the two radiotracers were >1459 Ci/mmol at the end of synthesis. [¹¹C]DMI and [¹¹C]HDMI have potential utility as PET radiotracers for the norepinephrine transporter

[en] This paper aims to obtain the optimal composite slender beam design for a rotor blade. The cross-sectional dimensions are considered as design variables. The objective is to optimize the box beam to attain a target matrix of stiffness values and maximum elastic coupling. The optimization process is performed using a genetic algorithm (GA), associated with a variational asymptotic method for the structural analysis. The stiffness control of arbitrary, complex section under some design condition is performed in composite beam where the geometrically nonlinear characteristic of the structure is considered. The objective function is defined as the weight, strength and fatigue life. The laminate thicknesses are to be determined optimally by defining a design index comprising a weighted average of the objective functions and determining the minimum.

[en] This study investigates the fatigue characteristics of SM 490 A material specimens for the railway vehicle due to the welding type. The more stress ratio decreases, the more strength of fillet welded specimen decreases. At specially, when the stress ratio of TN(Plate with transverse fillet welded rib) specimens decreases 0.5, 0.1, and -0.1, the fatigue limit decreases uniformly. The strength of TN is higher than it of NCN in the compare of fillet welding type, but the strength of NCN(Non load-carrying cruciform fillet welded joint) is higher than it of CN(Load-carrying cruciform fillet welded joint), which these specimens have the rib in the both side. We analysis the strains on the weld positions of the TN specimens during the fatigue test for the investigation of crack initiation and crack growth. In the theses results, we could find the fatigue crack initiation point and time

[en] In₂O₃ has a direct band gap with energy of 3.6 eV and is expected to be used in microelectronics devices such as solar cells, organic light-emitting diodes, flat-panel displays, and gas sensors. To fabricate an indium-oxide nano-particle, we deposited thin indium films with thickness of 5, 10, and 15 nm on Si substrates by using a thermal evaporator, and we spin-coated polyamic acid (PAA) on the indium films. They were cured at 400 .deg. C for 1 hour in a rapid thermal annealing system under a N₂ atmosphere. An electrical characterization of the indium-oxide nano-particles was carried out by using capacitance-voltage (C-V) measurement. This system shows a potential for device application such as a nano-floating gate memories.

[en] A mono-layer of quantum dots (QDs) was fabricated in polyimide matrix by chemical reaction between polyamic acid and metal thin film. This method has advantages of simple fabrication steps and diversity of material choice. Fe₂O₃ and ZnO QDs were embedded in a polyimide matrix, and their electrical charging effects were measured. From the magnetization analysis, the Fe₂O₃ particles not to have much of a γ-Fe₂O₃ crystal structure. From the magnetic force microscope (MFM) image of a single particle under a static magnetic filed, this fabrication method is thought to be able to produce only low-density magnetic QDs and the almost magnetic property the nonreacted Fe metal. Though only low-density magnetic particles are formed, the MFM image showed single γ-Fe₂O₃.

[en] Microlens is known for optical component that has a great deal of applications in the field of communication, medical equipment, multi media equipment, electronic equipment and so on. Thermal reflow method using photoresist, etching method using laser pulse, dry etching method, the glass surface treatment method using CO_2 gas laser have been known as manufacture methods of microlens. In this paper, we fabricated the arrays of microlenses from droplets using dispenser system. UV curable optical adhesive is transparent in the optical region with the transmittance of over 99% in the wavelength range from 350nm to 1300nm and it has a viscosity of 1900cP and it is possible to perform a spin coating process on surface of semiconductor with is. After the exposure by UV it does not be removed in the acetone although it is dissolve in the acetone in the general state. In the dispenser system we can do a fine control of the dispensing amount of the given glue using the control of the dispensing pressure and time. In this research, we fabricated UV curable optical adhesive microlens arrays using the dispenser system. We characterized the microlens array with measurement of a radius of curvature and a focal length of the microlens with a physical and optical method. As one application of the our method, we consider the integration of microlens on a light emitting diode

[en] If the electron distribution has anisotropy, the emissions from such plasma have some degree of polarization. To study the anisotropy of the electron distribution of laser produced plasmas, a polarization-resolved spectrometer was constructed and used to measure the degree of the polarization of emission from laser produced A1 plasmas. The laser was focused on the target surface and the diameter of the laser spot on the target surface was about 0.26 Mn. So the power density on the target surface was about 5 GW/cm². Using dichroic polarizer in front of the entrance slit of the spectrometer or placing a calcite crystal in front of the entrance slit of a Czerny-Turner spectrometer, the polarization of the spectrum is resolved. the focal length of the Czerny-Turner spectrometer is 1 m with a measured spectral resolution of 0.46 nm at 365 nm.

[en] CrMo alloy steel was nitrided using two types of processing methods, ion-nitriding processing and nitrocarburizing. Both processes were conducted for a duration of 30 min. To compare the surface hardness of the alloys created by the different processes , microhardness tests were conducted, and fatigue tests of each material were performed by a cantilever rotary bending fatigue test machine (Yamamoto, YRB 200) in the very high cycle regime (N > 10⁷cycle). Fractography of the fractured surfaces was conducted by scanning electron microscopy - to observe the fracture mechanisms of very high cycle fatigue and the effect of the nitriding process on the fatigue characteristics