Effects of Mn,P, and mo on sulfide stress cracking resistance of high strength low alloy steels

Effects of phosphorus, manganese, and molybdenum on sulfide stress cracking (SSC) resistance were investigated by the constant load SSC test for low alloy steels with tempered martensite struc-ture and yield strength of 690 MPa to 820 MPa. The SSC threshold stress begins to decrease with an increase in yield strength at a certain yield strength (an SSC critical strength). The fraction of inter-granular fracture surface begins to increase with an increase in yield strength at the SSC critical strength, while the fracture mode becomes transgranular below this strength. Furthermore, there ex-ists a relationship between an increase in the fraction of intergranular fracture surface and a decrease in the SSC threshold stress. A decrease in phosphorus and manganese content and an increase in molybdenum content make the SSC critical strength higher. These changes in content of chemical elements, therefore, lead to an increase in the SSC threshold stress due to a decrease in the amount of intergranular fracture surface above the SSC critical strength. Below the SSC critical strength, however, the change of the SSC threshold stress is not observed because the fracture mode remains fully transgranular. The SSC critical strength could be represented as a function of a parameter com-posed of manganese and phosphorus contents.     

Preparation of an activity-inhibiting monoclonal antibody against human placental aromatase cytochrome P450

We produced a murine monoclonal antibody (MAb) to human placental aromatase cytochrome P450. This MAb, designated MAb3-2C2, was selected on its ability to suppress aromatase activity. The specificity of this MAb was assessed by selective immunoprecipitation of 125I-labeled aromatase cytochrome P450 as well as by the identification of a 55-kDa protein, which was enriched and purified by immunoaffinity chromatography on a MAb-coupled Sepharose 4B column. The MAb was able to suppress both human placental and ovarian microsomal aromatase. Species differences of aromatase were recognized by MAb3-2C2 on the basis of differential immunosuppression of aromatase activity. The antibody had no effect on non-aromatase cytochrome P450s. MAb3-2C2 gave negative results with human placental aromatase P450 in the Western blot analysis. The data presented indicate that MAb3-2C2 is specific for aromatase cytochrome P450 and that its epitope is located in a fragile tertiary conformation of the enzyme, thus making it capable of sensitively affecting catalysis.     

Modification of preparation method for polymer inclusion membrane (PIM) to produce hollow fiber PIM

A new preparation method for polymer inclusion membrane (PIM) was developed. The preparation method—called post‐treatment method—is very convenient to prepare a hollow fiber PIM. Using this method, a commercial cellulose triacetate (CTA) hollow fiber membrane can be easily converted into a hollow fiber PIM. Thus, a CTA hollow fiber membrane was allowed to swell in 2‐nitrophenyl‐n‐octyl ether (NPOE) in the presence of chloroform as a solvent for CTA and N,N,N′,N′‐tetraoctyl‐3‐oxapentane diamide (TODGA) as a carrier. After evaporating chloroform, a hollow fiber PIM containing NPOE and TODGA was obtained. The result of the transport experiment of cerium(III) ions using the hollow fiber PIM showed that cerium ions were effectively transported from the feed solution to the strip solution through the hollow fiber PIM, indicating that the hollow fiber PIM was successfully prepared using the post‐treatment method. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 4372–4377, 2006     

Correlation of suppressed linoleic acid metabolism with the hypocholesterolemic action of eritadenine in rats

The dose-dependent effects of dietary eritadenine on the metabolism of linoleic acid and on the plasma cholesterol concentration were investigated to clarify the mechanism of the hypocholesterolemic action of eritadenine in rats. Rats were fed control or eritadenine-supplemented (2 to 20 mg/kg) diets for 14 d. Eritadenine supplementation significantly decreased both the plasma cholesterol concentration and the 20∶4n−6/18∶2n−6 ratio of liver microsomal and plasma phosphatidylcholine (PC) in a dose-dependent manner. Eritadenine was also found to decrease the activity of Δ6 desaturase in liver microsomes; these was significant correlation between the Δ6-desaturase activity and the 20∶4n−6/18∶2n−6 ratio in the PC of liver microsomes (r=0.989, P<0.001) or plasma (r=0.986, P<0.001). Certain plasma PC molecular species, as represented by 16:0-18:2, were increased by eritadenine in a dose-dependent manner, and certain plasma PC molecular species, as represented by 18:0-20:4, were conversely decreased by eritadenine. There was a significant correlation between the plasma total cholesterol concentration and the proportion of the sum of plasma PC molecular species which contain 18:1 or 18:2 in the sn-2 position. These results support the idea that the suppression of linoleic acid metabolism by eritadenine might be associated with the hypocholesterolemic action of eritadenine.     

Catalytic performance and QXAFS analysis of Ni catalysts modified with Pd for oxidative steam reforming of methane

Pd–Ni bimetallic catalysts prepared by co-impregnation and sequential impregnation methods were compared in the catalytic performance in oxidative steam reforming of methane. The sequential impregnation was more effective to the suppression of hot spot formation. According to the structural analysis by in situ quick-scanning X-ray absorption fine structure (QXAFS) during the temperature programmed reduction, the sequential impregnation method gave the bimetallic particles with higher Pd surface composition because of the low possibility of the Pd–Ni bond formation. Higher surface composition of Pd with higher reducibility than Ni is connected to the enhancement of the catalyst reducibility and the suppression of the hot spot formation.     

海洋深层水在日本食品生产中的应用概况及展望

在详细介绍了海洋深层水的优良资源特性的基础上,系统介绍了日本在食品、饮料制造、酿酒、制盐及制冰等多方面应用海洋深层水的最新成果,并展望了今后海洋深层水研究开发的前景。     

The importance of Fe loading on the N2O reduction with NH3 over Fe-MFI: Effect of acid site formation on Fe species

Effect of the loading amount of Fe over ion-exchanged Fe-MFI catalysts on the catalytic performance of N₂O reduction with NH₃ was investigated, and the results indicated that the turnover frequency (TOF) was almost constant in the Fe/Al range between 0.05 and 0.40. The activity of N₂O + NH₃ reaction was much lower than that of N₂O + CH₄ reaction over Fe-MFI (Fe/Al = 0.40), and the preadsorption of NH₃ decreased drastically the activity of N₂O + CH₄ reaction. The temperature-programmed desorption (TPD) of NH₃ showed the formation of stronger acid sites on Fe-MFI (Fe/Al = 0.24 and 0.40), and the amount of the acid sites agrees well with the desorption amount O₂ in O₂-TPD in the low temperature range. The acid sites gave a 3610 cm⁻¹ peak (Brønsted acid) in FTIR observation. These results suggest that the acid sites were formed on the bridge oxide ions in binuclear Fe species. Adsorbed NH₃ on the strong acid sites inhibited N₂O dissociation, which can be related to the low activity of N₂O + NH₃ reaction over Fe-MFI with high Fe loading.     

Enhancement of arachidonic acid production by Mortierella alpina 1S-4

The effect of mineral addition on arachidonic acid (AA) production by Mortierella alpina 1S-4 was evaluated. At first, the addition of minerals such as sodium, potassium, calcium, and magnesium was examined in flask cultures, and then the addition of phosphorus with the optimal amounts of the minerals was investigated in a 10-L jar-fermenter. As a result, 1.5% soy flour medium with the addition of 0.3% KH₂PO₄, 0.1% Na₂SO₄, 0.05% CaCl₂·2H₂O, and 0.05% MgCl₂·6H₂O was found to enhance the AA yield 1.7-fold over that without mineral addition. When 1% yeast extract with the above mineral mixture was used, the AA yield was enhanced 1.35-fold over that without minerals. We also verified that an increase in the polar lipid content occurred in the case of only KH₂PO₄ addition, and that the above-mentioned increase in the AA yield was due to the minerals themselves, not a pH buffer effect.     

Corneal Critical Barrier against the Penetration of Dexamethasone and Lomefloxacin Hydrochloride: Evaluation by the Activation Energy for Drug Partition and Diffusion in Cornea

The cornea is a solid barrier against drug permeation. We searched the critical barrier of corneal drug permeation using a hydrophobic drug, dexamethasone (DM), and a hydrophilic drug, lomefloxacin hydrochloride (LFLX). The activation energies for permeability of DM and LFLX across the intact cornea were 88.0 and 42.1 kJ/mol, respectively. Their activation energies for permeability across the cornea without epithelium decreased to 33.1 and 16.6 kJ/mol, respectively. The results show that epithelium is the critical barrier on the cornea against the permeation of a hydrophobic drug of DM as well as a hydrophilic drug of LFLX. The activation energy of partition for DM (66.8 kJ/mol) was approximately 3-fold larger than that of diffusion (21.2 kJ/mol). The results indicate that the partition for the hydrophobic drug of DM to the corneal epithelium is the primary barrier. Thermodynamic evaluation of activation energy for the drug permeation parameters is a good approch to investigate the mechanism of drug permeability.     

Investigation of false-positive reactions for CBH351 maize in screening PCR analysis

Examination for CBH351 maize was conducted by the qualitative polymerase chain reaction (PCR) method in maize grain and maize processed foods obtained in the Tokyo area. The numbers of samples possibly positive in the screening test were 7 of 22 (31.8%) for maize grain samples, 4 of 14 (28.6%) for semi-processed foods, 11 of 30 (36.7%) for canned products, 3 of 30 (10.0%) for maize snacks, 3 of 4 (75%) for tacos and 1 of 3 (33.3%) for tortillas. However, CBH351 maize was not detected in the confirmation test. Therefore, the results of the screening test were false-positive. Since the reaction might have been caused by the base sequences of the 3'-end of primers CaM03-5' and CBH02-3' used in the screening test, a new primer pair was designed. The PCR products obtained with the new primer pair TMC2-5'--TMS2-3' were specific for CBH351 and were not obtained with barley, wheat, rice, RRS, Bt11, or Event176. Thus, the new primer pair shows high specificity. CBH351 maize was detected from samples containing at least 0.05% CBH 351 maize DNA by using this primer pair.