The corrosion behaviour of chromium in hydrogen chloride gas and gas mixtures of hydrogen chloride and oxygen at high temperatures

A kinetic investigation of the CrHClO₂ system at 1 atm was carried out varying the oxygen content from 0 to 75 vol% at 400–800°C by the thermogravimetric method in stagnant gases and by measurements of weight loss and weight of sublimates after corrosion tests in flowing gases. In hydrogen chloride gas the corrosion rate is determined by the rates of formation and evaporation of a CrCl₂ scale: the scale was protective, to some extent, up to 600°C, but rapidly evaporated at still higher temperatures. The addition of oxygen led to suppression of corrosion loss up to about 500°C but to catastrophic corrosion at higher temperatures. The scale formed in the gas mixtures consisted mainly of Cr₂O₃ but vigorous vaporization of CrCl₂ and water occurred at the higher temperatures due to oxy-chlorination.     

基于μpd78F9222的无刷电机控制系统的实现

采用NEC微处理器μpd78F9222作为主控芯片,设计了具有价格和功能优势的无刷电机控制系统,可以应用于电动自行车的电机控制系统.该系统可替代目前大多采用的专用集成电路的设计方案,具有控制的实时性强、稳定性好,电路简单、性价比高等特点,目前已进入试生产阶段,具有良好市场前景.     

Fabrication of high‐quality two‐dimensional photonic crystals based on porous alumina

We fabricated porous alumina templates with a well‐ordered pore array by a pre‐triggered anodization method. The arrangement of pores in the fabricated templates was set by a Ni‐dot stamper. The structure of the templates was analyzed by field emission scanning electron microscopy (FESEM), two‐dimensional Fourier transformation of FESEM images and optical means. It was found that the porous alumina templates have a high‐quality, extended, two‐dimensional hexagonal lattice, which can be used in the fabrication of two‐dimensional magnetophotonic crystals (2D‐MPCs). © 2007 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

X-ray diffraction study of the effect of annealing temperature on the phase and structural states of Fe79Zr10N11 films produced by magnetron sputtering

Fe₇₉Zr₁₀N₁₁ films 0.7 μm thick deposited on glass substrates have been produced by rf reactive magnetron sputtering. The films are a soft magnetic material, which can exhibit a combination of a high saturation inductance and a low coercive force and, therefore, shows promise as magnetic recording cores for the high-density magnetic recording. The results of X-ray diffraction studies of the phase and structural states of the films and the effect of annealing on these states are considered.     

EXAFS characterization of bimetallic Pt–Pd/SiO2–Al2O3 catalysts for hydrogenation of aromatics in diesel fuel

Bimetallic Pt–Pd/SiO₂–Al₂O₃ catalysts exhibited much higher activities in aromatic hydrogenation of distillates than monometallic Pt/SiO₂–Al₂O₃ and Pd/SiO₂–Al₂O₃ catalysts. The studies of extended X‐ray absorption fine structure (EXAFS) indicated that there was an interaction between Pt and Pd in the Pt–Pd/ SiO₂–Al₂O₃ catalyst. Furthermore, from the EXAFS, it was assumed that the active metal particle on the Pt–Pd/SiO₂–Al₂O₃ catalysts is composed of the “Pd dispersed on Pt particle” structure. Regarding both the activities of aromatic hydrogenation and the EXAFS results, it was concluded that the Pd species dispersed on Pt particles were responsible for the high activity of the bimetallic Pt–Pd/SiO₂–Al₂O₃ catalysts. This revised version was published online in July 2006 with corrections to the Cover Date.     

Enzymatic synthesis of structured lipid containing arachidonic and palmitic acids

Human milk fat contains 20–25% palmitic acid, and about 70% of the fatty acid is esterified to the 2-position of triglycerides. It was also reported that arachidonic acid (AA) accelerated the growth of preterm infants. Thus, we attempted the synthesis of 1,3-arachidonoyl-2-palmitoyl-glycerol by acidolysis of tripalmitin with AA using 1,3-specific Rhizopus delemar lipase. When a mixture of 10 g tripalmitin/AA (1∶5, w/w) and 0.7 g immobilized Rhizopus lipase was incubated at 40°C for 24 h with stirring, the AA content in glycerides reached 59 mol%. The immobilized lipase could be used five times without a decrease in the extent of acidolysis. Glycerides were extracted from the reaction mixture with n-hexane, and regiospecific analysis was performed. As a result, the AA contents at the 1,3- and 2-positions were 56.9 and 3.2 mol%, respectively. It was therefore confirmed that the fatty acids at the 1,3-positions of triglyceride were exchanged for AA. High-performance liquid chromatography showed that the contents of triarachidonin, 1,3-arachidonoyl-2-palmitoyl-glycerol, and 1(3)-arachidonoyl-2,3(1)-palmitoyl-glycerol were 7.3, 75.9, and 12.4 wt%, respectively.     

Corrosion behavior of various steels in black liquor recovery boiler environment

It is important to examine characteristics of ash in order to understand the high temperature corrosion behavior of steels in the black liquor recovery boiler (BLRB) environment. The ash collected from the corroded superheater tubes was mainly composed of alkali-sulfates, alkali-chlorides and alkali-carbonates. The mole ratio of Na/K in the ash from BLRB ranged from 3 to 17. The concentration of sulfates varied over a range from 50 to 90 wt%, and chlorides from 0.1 to 10 wt%. On the base of these results, the corrosion behavior of various steels and the effect of alloying elements on the corrosion behavior of stainless steels in the BLRB environment were studied. From the results, Cr, Mn and Mo were significantly beneficial elements. N and Ni were also beneficial above 600 °C while C was an extremely harmful element. Subsequently, a new corrosion resistant stainless steel was selected as the material for the superheater in the BLRB.     

A Covalent Inhibitor for Glutathione S-Transferase Pi (GSTP1-1) in Human Cells

Glutathione S-transferase π (GSTP_1-1) is overexpressed in many types of cancer and is involved in drug resistance. Therefore, GSTP_1-1 is an important target in cancer therapy, and many GST inhibitors have been reported. We had previously developed an irreversible inhibitor, GS-ESF, as an effective GST inhibitor; however, its cellular permeability was too low for it to be used in inhibiting intracellular GST. We have now developed new irreversible inhibitors by introducing sulfonyl fluoride (SF) into chloronitrobenzene (CNB). The mechanism of action was revealed to be that CNBSF first reacts with glutathione (GSH) through an aromatic substitution in the cell, then the sulfonyl group on the GSH conjugate with CNBSF reacts with Tyr108 of GST to form a sulfonyl ester bond. Our new inhibitor irreversible inhibited GSTP_1-1 both in vitro and in cellulo with a long duration of action.     

L/N-Type Calcium Channel Blocker Cilnidipine Added to Renin-Angiotensin Inhibition Improves Ambulatory Blood Pressure Profile and Suppresses Cardiac Hypertrophy in Hypertension with Chronic Kidney Disease

Ambulatory blood pressure (BP) and heart rate (HR) profile are proposed to be related to renal deterioration and cardiovascular complication in hypertension and chronic kidney disease (CKD). In this study, we examined the beneficial effects cilnidipine, a unique L/N-type calcium channel blocker (CCB), in addition to renin-angiotensin system inhibitors, on ambulatory BP and HR profile, as well as cardiorenal function in hypertensive CKD patients. Forty-five patients were randomly assigned to the cilnidipine replacement group (n = 21) or the control CCBs group (n = 24) during a 24-week active treatment period. Although clinical BP values were similar in the cilnidipine and control CCBs groups after the treatment period, the results of ambulatory BP monitoring showed that the 24-h and daytime systolic BP levels in the cilnidipine group were significantly lower compared with the control group after the study. Furthermore, the left ventricular mass index (LVMI) was significantly decreased in the cilnidipine group compared to the control group after the study (LVMI, 135.3 ± 26.4 versus 181.2 ± 88.4, p = 0.031), with a significant difference in the changes in the LVMI between the cilnidipine and control groups (change in LVMI, −12.4 ± 23.7 versus 26.2 ± 64.4, p = 0.007). These results indicate that cilnidipine is beneficial for the suppression of pathological cardiac remodeling, at least partly, via a superior improving effect on ambulatory BP profile compared with control CCBs in hypertensive CKD patients.     

Effect of native microflora on the growth kinetics of salmonella enteritidis strain 04-137 in raw ground chicken

Effects of native microflora (NM) on growth kinetics of Salmonella Enteritidis strain 04-137 were studied in raw ground chicken. First, samples of ground chicken with high and low levels of NM (10(7.1) and 10(4.9) CFU/g, respectively) were spiked with Salmonella at doses ranging from 10(1) to 10(4) CFU/g. The growth kinetics, including the rate constant of growth, r, and the lag period, were similar, but the maximum cell level, N(max), was higher at higher initial Salmonella doses for both NM levels. Second, samples of ground chicken with high and low NM levels (10(6.8) and 10(4.7) CFU/g, respectively) were spiked with Salmonella and then stored at various constant temperatures ranging from 8 to 32°C. Both N(max) and r for Salmonella were higher at higher temperatures for both NM levels. Although r for total bacteria, which consisted of NM and Salmonella, was also higher at higher temperatures, N(max) was constant at all temperatures for both NM levels. Further, Salmonella growth was compared among samples of ground chicken with high and low NM levels and samples of sterilized chicken. Salmonella growth, characterized by both N(max) and r, was highest in sterilized chicken, followed by chicken with the low NM level. Our growth model successfully described and analyzed the growth of Salmonella and total bacteria in chicken at constant temperatures; using the data obtained, the model also successfully predicted the growth of Salmonella and total bacteria in chicken stored at dynamic temperatures. Our study clarified the effects that different doses of NM in ground chicken had on the growth kinetics of the Salmonella strain and demonstrated the usability of the growth model for foods with NM.