Synthesis and antimicrobial activity of 7-[2-(2-aminothiazol-4-YL) acetamido] cephalosporins

Thesis--University of Tsukuba, D.Sc.(B), no. 29, 1980. 3. 3

The realization of unaccentedness in Korean and Japanese pitch accent systems

In this paper, I discuss how unaccented words are realized in lexical pitch accent varieties of Korean and Japanese, focusing on Daegu/North Gyeongsang Korean. Previous studies such as Kenstowicz & Sohn (1997) and Jun et al. (2006) claim that Daegu Korean lacks an unaccented class. I show that the final-accented class in Daegu Korean proposed by Kenstowicz & Sohn (1997) and Jun et al. (2006) is in fact unaccented, comparing final-accented words in Daegu Korean with unaccented words in Tokyo Japanese in phrasal contexts. Most previous studies examined only the tone interaction between words and clitics to determine the accentedness or unaccentedness of the words, but this study demonstrates that phrasal prosody should also be considered to help identify the accentedness or unaccentedness of words

Evaluation of Performance of Heat Pump using R32 and HFO-mixed Refrigerant by Refrigeration Cycle Simulation and Loss analysis

R32 was selected as the alternative for R410A for mini-split air conditioners/heat pumps in Japan and have already phased out R410A in residential market. Recently several new alternatives for R410A have been proposed in order to achieve more close capacity to R410A and mitigate high discharge temperature issue of R32 as well as to reduce energy consumption. We selected R32 from among the candidates a few years ago; however it is important to continue comparing it to new candidates in search for an even better choice. We carried out the drop-in tests of the new refrigerant R32/R125/R1234yf (67/7/26) by comparing its COP and especially pressure loss to those of R410A, R32/R1234ze(E)(70/30), and R32, using residential mini-split type air conditioner. We conducted the drop-in tests by two types of method, actual measuring and especially simulated calculation. Adjusting compressor suction superheat and the amount of refrigerant charged into the system. Moreover, we measured the performance of the system with changing compressor speed in the wide range by variable frequency drive. Furthermore, we compared electricity consumption at the constant capacities, and analyzed the results precisely by loss analysis. As a result, we found that the COP of R32/R125/R1234yf (67/7/26) is better than R410A in many conditions and it achieves very close capacity to R410A, but COP at the same capacity is not as high as R32. The reason is that pressure losses are increased by adding R125 and R1234yf to R32. It was clarified, comparing losses with R410A, R32/1234ze(70/30), and R32. From the above, we confirmed that R32 is still the best choice at present. However, we will continue searching for a better alternative.

Unaccented and Final-Accented Classes in Lexical Pitch Accent Languages: A Case Study of Gyeongsang Korean

A number of researchers (Kenstowicz & Sohn, 1997; Jun et al., 2006, among others) have claimed that the pitch accent systems of Gyeongsang Korean (specifically North Gyeongsang Korean and South Gyeongsang Korean) lack an unaccented class and instead have a final-accented class. This claim contradicts recent work on the role of accentedness in wh-prosody in Gyeongsang Korean (Hwang 2011) and earlier research on Gyeongsang lexical pitch accent (Ramsey 1978). In this study, I provide additional prosodic evidence to support the claim that Gyeongsang Korean has an unaccented class. I also argue that a final-accented class in Gyeongsang Korean exists, but it is limited to loanwords. This study demonstrates the importance of using more than one diagnostic to identify accent classes in lexical pitch accent language

Performance Evaluation of Heat pump System using R32 and HFO-mixed Refrigerant in High Ambient Temperature.

R32 was selected as the alternative for R410A for mini-split air conditioners/heat pumps and already phased out R410A in residential market in Japan. Recently several new alternatives for R410A have been proposed in order to achieve more close capacity to R410A and mitigate high discharge temperature issue of R32 as well as to reduce energy consumption. We selected R32 from among the candidates a few years ago; however it is important to continue comparing it to new candidates in search for an even better choice. We carried out performance evaluation for the lower GWP refrigerant R32/R125/R1234yf (67/7/26) and R32. We also conducted the experiments in cooling operation at high ambient temperature. As the result, we found that the COP of R32 is superior to the blend because of its latent heat characteristic. In particular, as condensing temperature increases such as at high ambient temperature operation, latent heat of the blend obtains even smaller. Therefore, advantage of R32 in COP becomes more significant at high ambient conditions. From the above, we consider that R32 is still the best refrigerant at present. However, we will continue investigation in search for a better refrigerant