Dust Explosion Characteristics of Aluminum, Titanium, Zinc, and Iron-Based Alloy Powders Used in Cold Spray Processing

Compared to conventional thermal spray coating, cold spray processing typically employs finer, smaller-diameter metal powders. Furthermore, cold-sprayed particles exhibit fewer surface oxides than thermally sprayed particles due to the absence of particle melting during spraying. For these reasons, it is important to consider the potential for dust explosions or fires during cold spray processing, for both industrial and R&D applications. This work examined the dust explosion characteristics of metal powders typically used in cold spray coating, for the purpose of preventing dust explosions and fires and thus protecting the health and safety of workers and guarding against property damage. In order to safely make use of the new cold spray technology in industrial settings, it is necessary to manage the risks based on an appropriate assessment of the hazards. However, there have been few research reports focused on such risk management. Therefore, in this study, the dust explosion characteristics of aluminum, titanium, zinc, carbonyl iron, and eutectoid steel containing chromium at 4 wt.% (4 wt.% Cr-eutectoid steel) powders were evaluated according to the standard protocols JIS Z 8818, IEC61241-2-3(1994-09) section 3, and JIS Z 8817. This paper reports our results concerning the dust explosion properties of the above-mentioned metal powders.     

Distribution of the sulfite resistance gene SSU1-R and the variation in its promoter region in wine yeasts

The SSU1-R gene provides high sulfite resistance to the wine yeast Y9-16B. In this study, we examined the distribution of this gene in 61 wine yeasts and 4 laboratory yeasts. We also analyzed the number of repeats of a 76-bp promoter sequence and its relationship to sulfite resistance. We found that the SSU1-R gene was present in 31 of the 61 wine yeasts. Furthermore, we found that the number of repeats in the promoter region of SSU1-R varied from two to six. Using RsaI, which cuts only once in the repeat, we suggested that the repeats all consisted of the 76-bp sequence. Finally, we found that there was a complex relationship between the number of repeats and sulfite resistance.     

Gingival and dermal fibroblasts: their similarities and differences revealed from gene expression

Gene expression profiles in normal human gingival and dermal fibroblasts were investigated using DNA microarrays. Their fundamental characteristics were almost identical, but 5% of their genes were uniquely expressed. These results help us to choose an optimal cell source for effective fibroblast-based cell therapy that is dependent on differential gene expression profiles.     

Beef texture characterization using internationally established texture vocabularies in ISO5492:1992: Differences among four different end-point temperatures in three muscles of Holstein steers

‘Tenderness’ has been an important sensory characteristic for beef, although ‘tenderness’ has not been commonly defined. On the other hand, ISO5492:1992 provides internationally established vocabularies for sensory analysis with simple definition. The aim of this study was texture characterization for three beef muscles cooked to four end-point temperatures using ISO5492:1992 texture terms in Japanese to develop objective sensory evaluation terms for beef texture other than ‘tenderness.’ Longissimus, semitendinosus, and psoas major muscles harvested from three Holstein steers were cooked to 45, 60, 72, and 92 °C end-point temperatures and evaluated by a trained sensory panel. Correspondence analysis indicated that the ‘chewiness’ and ‘hardness’ defined in ISO5492 were distinguished in each muscle. Changes in the ‘chewiness’ and ‘hardness’ qualities during cooking were different from each other. These findings suggest that both ‘chewiness’ and ‘hardness’ as defined in ISO5492:1992 should be evaluated simultaneously to determine the sensory texture of beef.     

Directed evolution by accumulating tailored mutations: thermostabilization of lactate oxidase with less trade-off with catalytic activity

We assumed that adverse effects posed by introducing multiple mutations could be decomposed into those of each of the component mutations and that the risk could be reduced by the accumulation of mutations that were finely tuned for directed improvement of a specific property. We propose here a directed evolution strategy for improving a specific property with less effect on other ones. This strategy is composed of fine-tuning of mutations and their accumulation by our original mutation-assembling method. In this study, we selected lactate oxidase (LOX) as a model enzyme, because its directed evolution had showed a trade-off between thermostability and catalytic activity. Mutation profiling at each of the sites found by error-prone PCR revealed a strong inverse relationship between the two properties. Thermostable mutations with less effect on catalytic activity were selected at each site and accumulated with ideal combinations by our method. The resultant multiple mutants exhibited 5- to 10-fold superior catalytic activity and comparable thermostability with those created by accumulating thermostable mutations, which were not tuned for catalytic activity. This result demonstrates that the accumulation of fine-tuned mutations is an advantageous approach to reduce the risk of adverse effects posed by accumulating multiple mutations.     

Novel ion conductive matrix via dehydrocoupling polymerization of imidazolium-type ionic liquid and lithium 9-borabicyclo[3,3,1]nonane hydride

Summary An ion conductive zwitterionic polymer electrolyte containing borate units was prepared. The polymer was synthesized via dehydrocoupling of lithium 9-borabicyclo[3,3,1]nonane hydride (lithium 9-BBN hydride) with 1,3-dihydroxyethylimidazolium bromide and subsequent anion exchange reaction using lithium bis(trifluoromethylsulfonyl)imide (LiTFSI). The obtained polymer showed the ionic conductivity of 3.4×10^-6 Scm^-1 at 50 °C in spite of relatively high glass transition temperature (-6 °C).     

Assessment of China's climate commitment and non-fossil energy plan towards 2020 using hybrid AIM/CGE model

China made a commitment in Copenhagen to reduce its carbon dioxide emissions per unit of GDP from 40% to 45% compared with the 2005 level by 2020, and is determined to vigorously develop non-fossil fuels. This study analyzes the effects and impacts of policies that could help to achieve China's Copenhagen commitments with a hybrid static CGE model in which the electricity sector is disaggregated into 12 generation technologies. Four scenarios are developed, including the reference scenario A, the reference scenario B and two carbon constraint scenarios. The results show that carbon intensity in terms of GDP will fall by 30.97% between 2005 and 2020 in the reference scenario A, and will be reduced further by 7.97% if China's targeted non-fossil energy development plans can be achieved in the reference scenario B. However, the rest of the 40–45% target must be realized by other measures such as carbon constraint. It is also observed that due to carbon intensity constraints, GDP loss would be from 0.032% to 0.24% compared to the reference scenario B, and CO₂ emission reductions are due mainly to decreases in coal consumption in the electricity sector and manufacturing sector.     

Pretreatment with fine bubbles for effective zinc ion precipitation and removal from zinc electroplating wastewater

Heavy metals such as zinc are widely used in plating plants for the processing of material surfaces; therefore, an adequate wastewater treatment is required afterwards to comply with wastewater regulations. However, the presence of chemicals such as degreasing agents in the wastewater generated from the plating process inhibits the formation of hydroxides, thereby making treatment of wastewater and compliance with the stipulated regulations difficult. Herein, the effects of fine bubbles on oil cleaning and wastewater treatment were investigated for developing an alternative cleaning technology to degreasing agents. The concentration of fine bubbles significantly affected the oil cleaning. The fine bubbles demonstrated remarkable cleaning of highly viscous oil, which was difficult to remove using pure water. The high cleaning effect of fine bubbles on oil was achieved because of the hydrophobic interaction of the bubbles. Furthermore, a decrease in cleaning effect was observed for samples with uneven shapes, which was attributed to the difficulty in penetration of fine bubbles in materials with irregularities. Furthermore, fine bubble cleaning exhibited better efficiency for wastewater treatment than degreaser cleaning. Therefore, fine bubble cleaning is speculated to be an excellent cleaning technology with high oil cleaning effectiveness and improved wastewater treatability.     

Suppressed Hepatic Production of Indoxyl Sulfate Attenuates Cisplatin-Induced Acute Kidney Injury in Sulfotransferase 1a1-Deficient Mice

Endogenous factors involved in the progression of cisplatin nephropathy remain undetermined. Here, we demonstrate the toxico-pathological roles of indoxyl sulfate (IS), a sulfate-conjugated uremic toxin, and sulfotransferase 1A1 (SULT1A1), an enzyme involved in its synthesis, in cisplatin-induced acute kidney injury using Sult1a1-deficient (Sult1a1^-/- KO) mice. With cisplatin administration, severe kidney dysfunction, tissue damage, and apoptosis were attenuated in Sult1a1^-/- (KO) mice. Aryl hydrocarbon receptor (AhR) expression was increased by treatment with cisplatin in mouse kidney tissue. Moreover, the downregulation of antioxidant stress enzymes in wild-type (WT) mice was not observed in Sult1a1^-/- (KO) mice. To investigate the effect of IS on the reactive oxygen species (ROS) levels, HK-2 cells were treated with cisplatin and IS. The ROS levels were significantly increased compared to cisplatin or IS treatment alone. IS-induced increases in ROS were reversed by downregulation of AhR, xanthine oxidase (XO), and NADPH oxidase 4 (NOX4). These findings suggest that SULT1A1 plays toxico-pathological roles in the progression of cisplatin-induced acute kidney injury, while the IS/AhR/ROS axis brings about oxidative stress.