Effects of Growth Rates and Cooling Rates on Defect Generation in Melt-Grown Copper Crystals(Physics)

Single crystals of zone-refined Cu were grown from the melt at growth rates ranging from 0.1 to 29.0 mm/min and with cooling rates of the crystal after growth varying from 0.24 to 45℃/min. It was found that the growth rate had a very important effect on the generation of dislocations and their arrays, but the cooling rate of the crystal after growth had an important effect only when the crystal had been solidified at a rate of 0.1 mm/min

Upper Critical Field of Superconducting Amorphous Alloy Zr_<85>Si_<15>

The upper critical field H_ is measured for the amorphous superconductor Zr_Si_ (T_c=2.70 K, ρ_n=270 μΩ・cm) in the wide temperature range down to 50 mK. The conventional V-H recording in sweeping magnetic field and measurements of the flux flow resistivity defined by the I-V curve at constant field are done in order to clarify the resistive transition of the superconducting mixed-to-normal state in an amorphous superconductor with extreme softness in the flux pinning interaction. The results show the strong suppression of H_ at low temperatures, which is quite different from the upward deviation from the theoretical values H_^* due to the orbital pair breaking effect in the dirty limit, reported for some amorphous alloys. Analysis with the Werthamer-Helfand-Hohenberg theory which takes into account the effects of the orbital pair breaking, spin paramagnetism and spin-orbit interaction gives 1.51≤α≤1.77 and 1.0≤λ_≤1.7, where α is the impurity parameter and λ_ the spin orbit interaction parameter. This is the first implication for the superconductivity in amorphous alloys that the spin paramagnetic effect plays an important role in determining the low temperature H_ and the spin-orbit (spin-flip) scattering enhances H_ moderately. The counterevidence is produced to the previous observation that the upward deviation anomaly (H_>H_^*) is an intrinsic property in amorphous metals with high resitivity

An Upgradable Product Design Method for Improving Performance, CO2 Savings, and Production Cost Reduction: Vacuum Cleaner Case Study

Customers often discard products without considering the environmental load, because of the deterioration of their value even though they are fully functional. An upgradable product design can enhance the product value and stop the entire product replacement and disposal by replacing only the components responsible for the decrease in value. This paper proposes an upgradable product design method for improving product performance, incurring CO2 savings, and production cost reduction while increasing the product value and extending the value lifespan by exchanging components closely related to the deterioration in value. In addition, this paper proposes a method that can specify future product performance, effective upgradable product components, and the effect of the upgrade on other product components. Finally, this paper discusses the applicability of the proposed method by considering the designing of a vacuum cleaner and customer demands such as performance, noise, and energy savings

Optimal Disassembly System Design with Environmental and Economic Parts Selection for CO2 Saving Rate and Recycling Cost

For promoting material circulation by recycling and preventing global warming caused by CO2 emissions simultaneously, it is essential for recycling factories of end-of-life assembly products to economically disassemble and recover the parts/materials with higher CO2 volumes which can save the CO2 emissions comparing to produce the same virgin parts/materials.This paper proposes a disassembly system design with an optimal environmental and economic parts selection which harmonizes a CO2 saving rate and recycling cost using a Life Cycle Inventory (LCI) database. The first stage is to optimize the environmental and economic parts selection by the integer programming with constraint, and the second stage is to carry out the disassembly line balancing for minimizing the number of stations