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The band structures and band gap energies, Eg, of passive films formed on titanium (Ti) in simulated bioliquids, Hanks’ solution (Hanks) and saline, were evaluated. Ti was polarized at 0, −0.1, and −0.2 VAg/AgCl, Ef, for 1 h. After polarization, the surfaces were characterized using X-ray photoelectron spectroscopy, and the photoelectrochemical responses were evaluated. The current change during photoirradiation was recorded as a photocurrent transient at each measuring potential, Em, and by changing the wavelength of the incident light. Passive films consisted of a very thin TiO2 layer containing small amounts of Ti2O3 and TiO, hydroxyl groups, and water. During polarization in Hanks, calcium and phosphate ions were incorporated or formed calcium phosphate but not in saline. Calcium phosphate and hydroxyl groups influenced the band structure. Eg was graded in Hanks but constant in saline, independent of Ef and Em. The passive film on Ti behaved as an n-type semiconductor containing two layers: an inner oxide layer with a large Eg and an outer hydroxide layer with a small Eg. In Hanks, Eg was 3.3–3.4 eV in the inner oxide layer and 2.9 eV in the outer hydroxide layer. In saline, Eg was 3.3 eV in the inner layer and 2.7 eV in the outer layer. Calcium phosphate and hydroxyl groups influenced the band structure of the passive film. The Eg of the outermost surface was smaller than that of TiO2 ceramics, which is probably one of the principles of the excellent biocompatibility of Ti among metals.

The band structures and band gap energies, Eg, of passive films formed on titanium (Ti) in simulated bioliquids, Hanks’ solution (Hanks) and saline, were evaluated. Ti was polarized at 0, −0.1, and −0.2 VAg/AgCl, Ef, for 1 h. After polarization, the surfaces were characterized using X-ray photoelectron spectroscopy, and the photoelectrochemical responses were evaluated. The current change during photoirradiation was recorded as a photocurrent transient at each measuring potential, Em, and by changing the wavelength of the incident light. Passive films consisted of a very thin TiO2 layer containing small amounts of Ti2O3 and TiO, hydroxyl groups, and water. During polarization in Hanks, calcium and phosphate ions were incorporated or formed calcium phosphate but not in saline. Calcium phosphate and hydroxyl groups influenced the band structure. Eg was graded in Hanks but constant in saline, independent of Ef and Em. The passive film on Ti behaved as an n-type semiconductor containing two layers: an inner oxide layer with a large Eg and an outer hydroxide layer with a small Eg. In Hanks, Eg was 3.3–3.4 eV in the inner oxide layer and 2.9 eV in the outer hydroxide layer. In saline, Eg was 3.3 eV in the inner layer and 2.7 eV in the outer layer. Calcium phosphate and hydroxyl groups influenced the band structure of the passive film. The Eg of the outermost surface was smaller than that of TiO2 ceramics, which is probably one of the principles of the excellent biocompatibility of Ti among metals.

Koichiro Watanabe,1 Shinji Fujimoto,2 Tatsuro Marumoto,2 Tadayuki Kitagawa,3 Kazuyuki Ishida,3 Tadashi Nakajima,2 Yoshiya Moriguchi,4 Keita Fujikawa,2 Takeshi Inoue5 1Department of Neuropsychiatry, Kyorin University School of Medicine, Tokyo, Japan; 2Japan Medical Office, Takeda Pharmaceutical Co., Ltd, Tokyo, Japan; 3Takeda Development Center – Japan, Takeda Pharmaceutical Co., Ltd, Osaka, Japan; 4Medical Affairs, Lundbeck Japan K.K., Tokyo, Japan; 5Department of Psychiatry, Tokyo Medical University, Tokyo, JapanCorrespondence: Koichiro Watanabe, Department of Neuropsychiatry, Kyorin University School of Medicine, 6-20-2 Shinkawa, Mitaka, Tokyo, 181-8611, Japan, Tel +81-422-47-5511, Fax +81-422-45-4697, Email koichiro@tke.att.ne.jpAim: Anhedonia in major depressive disorder may be resistant to first-line antidepressants. We examined the effect of vortioxetine, a multimodal antidepressant, on anhedonia-like symptoms in Japanese patients with major depressive disorder.Methods: This was a post hoc analysis of an 8-week, randomized, double-blind, placebo-controlled, phase 3 study of vortioxetine (10 mg or 20 mg) in Japanese patients aged 20– 75 years with recurrent major depressive disorder and a Montgomery–Åsberg Depression Rating Scale (MADRS) total score of at least 26. The primary outcome was the mean change from baseline to week 8 in anhedonia-like symptoms as measured by MADRS anhedonia factor score, composed of: Q1, apparent sadness; Q2, reported sadness; Q6, concentration; Q7, lassitude; and Q8, inability to feel. Mean change in MADRS total score and anhedonia factor score were compared among treatment groups, with data categorized by median baseline anhedonia factor score (0– 17 or ≥ 18).Results: Data were available for 489 patients. The least-squares mean difference in MADRS anhedonia factor score change from baseline to week 8 versus placebo was − 1.34 for vortioxetine 10 mg (P = 0.0300) and − 1.77 for vortioxetine 20 mg (P = 0.0044). The leas

Stress corrosion cracking (SCC) of pure copper in bentonite clay was examined using a slow strain rate test (SSRT). Bentonite was swollen with pure water or aqueous solutions containing NH₃ of 5 and 10 mM. Thick corrosion films and particulate deposits were formed on the copper surface after the SSRT. Typical tarnish rupture-type SCC occurred on pure copper in swollen bentonite with and without NH₃. The crack propagation rate was enhanced by NH₃. It is confirmed that a thick oxide layer was formed on copper during plastic deformation, resulting in tarnish crack-type SCC. Many particulate deposits observed on the surface were formed due to the rapid dissolution of Cu²⁺ ions to form porous CuO at local deformed sites, regardless of the SCC occurrence.

Takeshi Inoue,1 Shinji Fujimoto,2 Tatsuro Marumoto,2 Tadayuki Kitagawa,3 Kazuyuki Ishida,3 Tadashi Nakajima,2 Yoshiya Moriguchi,4 Keita Fujikawa,2 Koichiro Watanabe5 1Department of Psychiatry, Tokyo Medical University, Tokyo, Japan; 2Japan Medical Office, Takeda Pharmaceutical Co., Ltd, Tokyo, Japan; 3Takeda Development Center – Japan, Takeda Pharmaceutical Co., Ltd, Osaka, Japan; 4Medical Affairs, Lundbeck Japan K.K., Tokyo, Japan; 5Department of Neuropsychiatry, Kyorin University School of Medicine, Tokyo, JapanCorrespondence: Takeshi InoueDepartment of Psychiatry, Tokyo Medical University, 6‐7‐1 Nishishinjuku, Shinjuku‐ku, Tokyo, 160‐0023, JapanTel +81-3-3342-6111 (ext. 5754)Fax +81-3-3340-4499Email tinoue@tokyo-med.ac.jpAim: Antidepressants, including selective serotonin reuptake inhibitors, often elicit a poor response in patients with major depressive disorder (MDD) with significant anxiety symptoms. This study investigated the effects of the multimodal antidepressant vortioxetine in patients with MDD and associated anxiety.Methods: This was a post hoc analysis of data from an 8-week, randomized, double-blind, placebo-controlled, Phase 3 study of vortioxetine (10 mg or 20 mg) in Japanese patients aged 20– 75 years with recurrent MDD and a Montgomery–Åsberg Depression Rating Scale (MADRS) score of at least 26. Changes from baseline to week 8 in MADRS total score and Hamilton Depression Rating Scale (HAM-D) anxiety/somatization factor score were assessed in patients with anxious depression (HAM-D anxiety/somatization factor score ≥ 7) and without anxious depression.Results: Data were available for 489 patients. In patients with anxious depression, the least-squares (LS) mean difference (95% confidence interval [CI]) versus placebo in change in MADRS total score was − 3.44 (− 6.10, − 0.77) for vortioxetine 10 mg and − 4.51 (− 7.15, − 1.87) for vortioxetine 20 mg. In patients with non-anxious depression, the LS mean difference (95% CI)

Takeshi Inoue,1 Shinji Fujimoto,2 Tatsuro Marumoto,2 Tadayuki Kitagawa,3 Kazuyuki Ishida,3 Tadashi Nakajima,2 Yoshiya Moriguchi,4 Keita Fujikawa,2 Koichiro Watanabe5 1Department of Psychiatry, Tokyo Medical University, Tokyo, Japan; 2Japan Medical Office, Takeda Pharmaceutical Co., Ltd, Tokyo, Japan; 3Takeda Development Center – Japan, Takeda Pharmaceutical Co., Ltd, Osaka, Japan; 4Medical Affairs, Lundbeck Japan K.K., Tokyo, Japan; 5Department of Neuropsychiatry, Kyorin University School of Medicine, Tokyo, JapanCorrespondence: Takeshi InoueDepartment of Psychiatry, Tokyo Medical University, 6‐7‐1 Nishishinjuku, Shinjuku‐ku, Tokyo, 160‐0023, JapanTel +81-3-3342-6111 (ext. 5754)Fax +81-3-3340-4499Email tinoue@tokyo-med.ac.jpAim: Several weeks of treatment with an antidepressive agent may be required before efficacy is demonstrated in patients with major depressive disorder. This study investigated the predictive value of early partial improvement with vortioxetine for treatment response and remission.Methods: This was a post hoc analysis of an 8-week, randomized, double-blind, placebo-controlled, Phase 3 study of vortioxetine (10 mg or 20 mg) in Japanese patients aged 20– 75 years with recurrent major depressive disorder and a Montgomery–Åsberg Depression Rating Scale (MADRS) score of at least 26. The key outcomes were the predictive value of early partial improvement (reduction in MADRS total score of ≥ 20% from baseline to week 2) with vortioxetine for MADRS response (≥ 50% decrease in score from baseline) and remission (decrease in score to ≤ 10) at week 8.Results: Relevant data were available for 478 patients; 62/158 patients receiving placebo, 71/162 receiving vortioxetine 10 mg, and 66/158 receiving vortioxetine 20 mg were early improvers. Early improvers receiving vortioxetine (10 mg or 20 mg) were more likely than non-early improvers to achieve a week 8 response (71.2– 73.2% vs 29.7– 38.0%) or remission (50.7– 51.5% vs 17.4– 18.7

The present work aimed to investigate the pretreatment of oil palm mesocarp fiber (OPMF) in subcritical H2O-CO2 at a temperature range from 150–200 °C and 20–180 min with CO2 pressure from 3–5 MPa. The pretreated solids and liquids from this process were separated by filtration and characterized. Xylooligosaccharides (XOs), sugar monomers, acids, furans and phenols in the pretreated liquids were analyzed by using HPLC. XOs with a degree of polymerization X2–X4 comprising xylobiose, xylotriose, xylotetraose were analyzed by using HPAEC-PAD. Enzymatic hydrolysis was performed on cellulose-rich pretreated solids to observe xylose and glucose production. An optimal condition for XOs production was achieved at 180 °C, 60 min, 3 MPa and the highest XOs obtained was 81.60 mg/g which corresponded to 36.59% of XOs yield from total xylan of OPMF. The highest xylose and glucose yields obtained from pretreated solids were 29.96% and 84.65%, respectively at cellulase loading of 10 FPU/g-substrate.

The present work aimed to investigate the pretreatment of oil palm mesocarp fiber (OPMF) in subcritical H2O-CO2 at a temperature range from 150–200 °C and 20–180 min with CO2 pressure from 3–5 MPa. The pretreated solids and liquids from this process were separated by filtration and characterized. Xylooligosaccharides (XOs), sugar monomers, acids, furans and phenols in the pretreated liquids were analyzed by using HPLC. XOs with a degree of polymerization X2–X4 comprising xylobiose, xylotriose, xylotetraose were analyzed by using HPAEC-PAD. Enzymatic hydrolysis was performed on cellulose-rich pretreated solids to observe xylose and glucose production. An optimal condition for XOs production was achieved at 180 °C, 60 min, 3 MPa and the highest XOs obtained was 81.60 mg/g which corresponded to 36.59% of XOs yield from total xylan of OPMF. The highest xylose and glucose yields obtained from pretreated solids were 29.96% and 84.65%, respectively at cellulase loading of 10 FPU/g-substrate.

Oil palm mesocarp fiber was subjected to hydrothermal pretreatment under isothermal and non-isothermal conditions. The pretreated slurries were separated by filtration, pretreated liquids and solids were characterized. An enzymatic digestibility study was performed for both pretreated slurries and solids to understand the effect of soluble inhibitors generated during the pretreatment process. The highest glucose yield obtained from pretreated slurries was 70.1%, and gradually decreased with higher pretreatment severities. The highest glucose yield obtained in pretreated solids was 100%, after pretreatment at 210 °C for 20 min. In order to study the inhibitory effects of compounds generated during pretreatment with cellulase, technical grade solutions that mimic the pretreated liquid were prepared and their effect on Acremonium cellulase activity was monitored using Avicel. Xylo-oligomers and tannic acid were identified as powerful inhibitors of Acremonium cellulase, and the lowest hydrolysis rate of Avicel of 0.18 g/g-glucose released/L/h was obtained from tannic acid.

Oil palm mesocarp fiber was subjected to hydrothermal pretreatment under isothermal and non-isothermal conditions. The pretreated slurries were separated by filtration, pretreated liquids and solids were characterized. An enzymatic digestibility study was performed for both pretreated slurries and solids to understand the effect of soluble inhibitors generated during the pretreatment process. The highest glucose yield obtained from pretreated slurries was 70.1%, and gradually decreased with higher pretreatment severities. The highest glucose yield obtained in pretreated solids was 100%, after pretreatment at 210 °C for 20 min. In order to study the inhibitory effects of compounds generated during pretreatment with cellulase, technical grade solutions that mimic the pretreated liquid were prepared and their effect on Acremonium cellulase activity was monitored using Avicel. Xylo-oligomers and tannic acid were identified as powerful inhibitors of Acremonium cellulase, and the lowest hydrolysis rate of Avicel of 0.18 g/g-glucose released/L/h was obtained from tannic acid.

Combined pretreatment with hot compressed water and wet disk milling was performed with the aim to reduce the natural recalcitrance of oil palm biomass by opening its structure and provide maximal access to cellulase attack. Oil palm empty fruit bunch and oil palm frond fiber were first hydrothermally pretreated at 150-190° C and 10-240 min. Further treatment with wet disk milling resulted in nanofibrillation of fiber which caused the loosening of the tight biomass structure, thus increasing the subsequent enzymatic conversion of cellulose to glucose. The effectiveness of the combined pretreatments was evaluated by chemical composition changes, power consumption, morphological alterations by SEM and the enzymatic digestibility of treated samples. At optimal pretreatment process, approximately 88.5% and 100.0% of total sugar yields were obtained from oil palm empty fruit bunch and oil palm frond fiber samples, which only consumed about 15.1 and 23.5 MJ/kg of biomass, respectively.

Combined pretreatment with hot compressed water and wet disk milling was performed with the aim to reduce the natural recalcitrance of oil palm biomass by opening its structure and provide maximal access to cellulase attack. Oil palm empty fruit bunch and oil palm frond fiber were first hydrothermally pretreated at 150-190° C and 10-240 min. Further treatment with wet disk milling resulted in nanofibrillation of fiber which caused the loosening of the tight biomass structure, thus increasing the subsequent enzymatic conversion of cellulose to glucose. The effectiveness of the combined pretreatments was evaluated by chemical composition changes, power consumption, morphological alterations by SEM and the enzymatic digestibility of treated samples. At optimal pretreatment process, approximately 88.5% and 100.0% of total sugar yields were obtained from oil palm empty fruit bunch and oil palm frond fiber samples, which only consumed about 15.1 and 23.5 MJ/kg of biomass, respectively.

Oil palm biomass, namely empty fruit bunch and frond fiber, were pretreated using a planetary ball mill. Particle sizes and crystallinity index values of the oil palm biomass were significantly reduced with extended ball mill processing time. The treatment efficiency was evaluated by the generation of glucose, xylose, and total sugar conversion yields from the pretreatment process compared to the amount of sugars from raw materials. Glucose and xylose contents were determined using high-performance liquid chromatography. An increasing trend in glucose and xylose yield as well as total sugar conversion yield was observed with decreasing particle size and crystallinity index. Oil palm frond fiber exhibited the best material yields using ball milling pretreatment with generated glucose, xylose, and total sugar conversion yields of 87.0, 81.6, and 85.4 %, respectively. In contrast, oil palm empty fruit bunch afforded glucose and xylose of 70.0 and 82.3 %, respectively. The results obtained in this study showed that ball mill-treated oil palm biomass is a suitable pretreatment method for high conversion of glucose and xylose.

Oil palm biomass, namely empty fruit bunch and frond fiber, were pretreated using a planetary ball mill. Particle sizes and crystallinity index values of the oil palm biomass were significantly reduced with extended ball mill processing time. The treatment efficiency was evaluated by the generation of glucose, xylose, and total sugar conversion yields from the pretreatment process compared to the amount of sugars from raw materials. Glucose and xylose contents were determined using high-performance liquid chromatography. An increasing trend in glucose and xylose yield as well as total sugar conversion yield was observed with decreasing particle size and crystallinity index. Oil palm frond fiber exhibited the best material yields using ball milling pretreatment with generated glucose, xylose, and total sugar conversion yields of 87.0, 81.6, and 85.4 %, respectively. In contrast, oil palm empty fruit bunch afforded glucose and xylose of 70.0 and 82.3 %, respectively. The results obtained in this study showed that ball mill-treated oil palm biomass is a suitable pretreatment method for high conversion of glucose and xylose.

Norihisa Koyama,1 Masanori Kouwaki,1 Taihei Tanaka,2 Shigeru Ohki,3 Kazuhiro Iwase,4 Shunichi Terasawa,5 Masanao Miyaji,6 Toshimitsu Iwaki,7 Minoru Kokubo,8 Satoru Kobayashi,9 Haruo Mizuno,10 Shinji Fujimoto,10 Hajime Togari10 1Department of Pediatrics, Toyohashi Municipal Hospital, Toyohashi, 2Department of Pediatrics, Nagoya Daini Red Cross Hospital, Nagoya, 3Department of Pediatrics, Seirei Hamamatsu General Hospital, Hamamatsu, 4Department of Pediatrics, Nagoya City West Medical Center, Nagoya, 5Department of Pediatrics, Ichinomiya Municipal Hospital, Ichinomiya, 6Department of Pediatrics, Shizuoka Saiseikai General Hospital, Shizuoka, 7Department of Pediatrics, Gifu Prefectural Tajimi Hospital, Tajimi, 8Department of Pediatrics, Kainan Hospital Aichi Prefectural Welfare Federation of Agricultural Cooperatives, Yatomi, 9Department of Pediatrics, Seirei Mikatabara General Hospital, Hamamatsu, 10Department of Pediatrics, Neonatology and Congenital Disorders, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan Background: Sudden unpredictable hypotension during the post-transitional period, termed late-onset circulatory dysfunction (LCD) of premature infants, has been reported in low birth-weight infants who overcame major problems during the early neonatal period. We investigated the clinical features of LCD and factors associated with the occurrence of LCD. Methods: A multicenter retrospective case-control study. The clinical records of 1,004 children born at less than 32 weeks of gestation were reviewed. Patients with LCD were compared with age-matched non-LCD controls. Results: Of the 1,004 infants, 73 (7.3%) were diagnosed with LCD, with the incidence differing significantly among institutions (P<0.0001). The median age of diagnosis was 16 days of age (range: 4–50 days) and 29 weeks of postmenstrual age (range: 25–35 weeks). The incidence of LCD was inversely correlated with gestational age at birth, except at 2

オーバーパックの腐食寿命については、これまで、日本の幅広い地質環境条件を想定した実験データや既往研究等に基づいて検討が行われてきた。しかしながら、高pH環境での挙動,ニアフィールド環境条件の時間的な変化に伴う挙動,溶接部の腐食挙動等、長期的な信頼性を向上させるとともに、オーバーパック設計を具体化するうえでの課題がある。このような状況を考慮して、(財)原子力安全研究協会内に国内の金属の腐食科学分野の専門家からなる「オーバーパックの長期安定性に関する調査専門委員会」を設置し、既往の研究成果と安全評価上の考え方について、金属の腐食科学の観点から長期耐食性に関する調査検討を行った。, The corrosion life time of the overpack has been investigated on the basis of experimental data and past research, assuming the ranging geological environment of Japan. However, some subject for the realization of the overpack design, such as the behavior of the overpack under high pH conditions, the behavior of the overpack with change of near-field environmental condition and the corrosion behavior of the welds have still been left. To take into account these conditions, expert committee composed of metal corrosion science experts were established in the Nuclear Safety Research Association and past research outcomes and the theory of safety assessment for long term corrosion resistance were investigated from the view points of metal corrosion science., 著者所属: 日本原子力研究開発機構(JAEA), JAEA-Research 2007-086

旧核燃料サイクル開発機構では、「我が国における高レベル放射性廃棄物地層処分の技術的信頼性; 地層処分研究開発第2次取りまとめ」(「第2次取りまとめ」)報告書を国に提出し、日本の幅広い地質環境条件を想定して実験データや既往研究等に基づいてオーバーパックの腐食寿命について検討を行った。しかしながら、高pH環境での挙動,ニアフィールド環境条件の時間的な変化に伴う人工バリアの挙動など長期的な信頼性を向上させるうえでの課題がある。このような状況を考慮して、原子力安全研究協会内に国内の金属の腐食科学分野の専門家からなる「オーバーパックの長期安定性に関する調査専門委員会」を設置し、既往の研究成果と安全評価上の考え方について、人工バリア材の長期安定性,長期耐食性の観点から調査検討を行った。, The Japan Nuclear Cycle Development Institute submitted "Second Progress Report on Research and Development for the Geological Disposal of HLW in Japan" to the Japanese government. This report contains investigations of the corrosion life time of the overpack on the basis of experimental data and past research, assuming the ranging geological environment of Japan. However some subjects, such as the behavior of the overpack under high pH conditions and the behavior of the engineering barrier with change of near-field environmental condition with time for promoting reliability have still been left. To take into account these conditions, expert committee composed of metal corrosion science experts were established in the Nuclear Safety Research Association and past research outcomes and the theory of safety assessment were investigated from the view points of long term stability and corrosion resistance of engineering barrier., 著者所属: 日本原子力研究開発機構(JAEA), JAEA-Research 2006-058

Direct plating of electroless Ni-P layers on Al-Ni alloy films formed on glass substrates was performed using magnetron-sputtered deposition and ion beam-assisted deposition methods. Dissolution of Al from the alloy films occurred in the initial stage of the plating process and resulted in enrichment of Ni on the surface. Since Ni acts as a catalyst for the Ni-P deposition reaction, Ni-P deposition occurs on the alloy surface without zincate pretreatment. In the case of an Al-10Ni alloy film, however, Ni clusters dropped from the Al-Ni alloy surface, and Ni-P particles grew in the plating bath, causing dissipation of chemicals in the bath. Such particles also readhered to the surface, resulting in a nonuniform plating layer. A lower concentration of Ni in an alloy such as an Al-3Ni or Al-1Ni alloy resulted in a rather smooth plating surface. In the case of a neutral plating bath containing a low concentration of P, cone structures were formed in the plating layer. Such structures seem to form at the nucleation sites of Ni deposition in the initial stage of the plating process. ©2003 The Electrochemical Society. All rights reserved.

Direct plating of electroless Ni-P layers on Al-Ni alloy films formed on glass substrates was performed using magnetron-sputtered deposition and ion beam-assisted deposition methods. Dissolution of Al from the alloy films occurred in the initial stage of the plating process and resulted in enrichment of Ni on the surface. Since Ni acts as a catalyst for the Ni-P deposition reaction, Ni-P deposition occurs on the alloy surface without zincate pretreatment. In the case of an Al-10Ni alloy film, however, Ni clusters dropped from the Al-Ni alloy surface, and Ni-P particles grew in the plating bath, causing dissipation of chemicals in the bath. Such particles also readhered to the surface, resulting in a nonuniform plating layer. A lower concentration of Ni in an alloy such as an Al-3Ni or Al-1Ni alloy resulted in a rather smooth plating surface. In the case of a neutral plating bath containing a low concentration of P, cone structures were formed in the plating layer. Such structures seem to form at the nucleation sites of Ni deposition in the initial stage of the plating process. ©2003 The Electrochemical Society. All rights reserved.

The characteristics of double zincate pretreatment of thin Al films deposited on glass plates using magnetron sputtering and ion-beam sputtering were investigated. Traces of Zn deposition and immersion potential as well as surface observations using scanning electron microscopy and atomic force microscopy showed that continuous dissolution of an Al film during the double zincate pretreatment occurred in the case of a magnetron sputter deposited film, resulting in Al film failure from the substrate. On the other hand, the substitution reaction of Al dissolution and Zn deposition occurring on the ion-beam sputter-deposited film ceased during the first and the second zincate treatment processes. The difference between the behaviors of the double zincate treatments for the two kinds of sputter-deposited films is related to the film structure. A magnetron sputter-deposited film has a columnar structure, resulting in higher susceptibility to the dissolution reaction in a concentrated alkaline zincate solution. On the other hand, an ion-beam sputter-deposited film has a fine microcrystalline structure with a low density of defects, resulting in lower susceptibility to the dissolution reaction. ©2001 The Electrochemical Society. All rights reserved.

The characteristics of double zincate pretreatment of thin Al films deposited on glass plates using magnetron sputtering and ion-beam sputtering were investigated. Traces of Zn deposition and immersion potential as well as surface observations using scanning electron microscopy and atomic force microscopy showed that continuous dissolution of an Al film during the double zincate pretreatment occurred in the case of a magnetron sputter deposited film, resulting in Al film failure from the substrate. On the other hand, the substitution reaction of Al dissolution and Zn deposition occurring on the ion-beam sputter-deposited film ceased during the first and the second zincate treatment processes. The difference between the behaviors of the double zincate treatments for the two kinds of sputter-deposited films is related to the film structure. A magnetron sputter-deposited film has a columnar structure, resulting in higher susceptibility to the dissolution reaction in a concentrated alkaline zincate solution. On the other hand, an ion-beam sputter-deposited film has a fine microcrystalline structure with a low density of defects, resulting in lower susceptibility to the dissolution reaction. ©2001 The Electrochemical Society. All rights reserved.

Shota Hayashida, Masamitsu Takahashi, Hiroshi Deguchi, Hiroaki Tsuchiya, Koushu Hanaki, Masato Yamashita, Shinji Fujimoto, Structure of Corrosion Product Formed on Carbon Steel Covered with NiSO4-Added Resin Coating under Sulfuric Acid Mist Environment Containing Chloride, Materials Transactions, 2021, Volume 62, Issue 6, Pages 781-787, Released on J-STAGE May 25, 2021, Advance online publication May 14, 2021, Online ISSN 1347-5320, Print ISSN 1345-9678, https://doi.org/10.2320/matertrans.C-M2021819.

Miyabe S., Fujinaga Y., Tsuchiya H., et al. TiO₂ nanotubes with customized diameters for local drug delivery systems. Journal of Biomedical Materials Research - Part B Applied Biomaterials 112, e35445 (2024); https://doi.org/10.1002/jbm.b.35445., In this study, we evaluated the drug release behavior of diameter customized TiO₂ nanotube layers fabricated by anodization with various applied voltage sequences: conventional constant applied potentials of 20 V (45 nm) and 60 V (80 nm), a 20/60 V stepped potential (50 nm [two-diameter]), and a 20–60 V swept potential (49 nm [full-tapered]) (values in parentheses indicate the inner tube diameter at the top part of nanotube layers). The structures of the 50 nm (two-diameter) and 49 nm (full-tapered) samples had smaller inner diameters at the top part of nanotube layers than that of the 80 nm sample, while the outer diameters at the bottom part of nanotube layers were almost the same size as the 80 nm sample. The 80 nm sample, which had the largest nanotube diameter and length, exhibited the greatest burst release, followed by the 50 nm (two-diameter), 49 nm (full-tapered), and 45 nm samples. The initial burst released drug amounts and release rates from the 50 nm (two-diameter) and 49 nm (full-tapered) samples were significantly suppressed by the smaller tube top. On the other hand, the largest proportion of the slow released drug amount to the total released drug amount was observed for the 50 nm (two-diameter) sample. Thus, 50 nm (two-diameter) achieved suppressed initial burst release and large storage capacity. Therefore, this study has, for the first time, applied TiO₂ nanotube layers with modulated diameters (two-diameter and full-tapered) to the realization of a localized drug delivery system (LDDS) with customized drug release properties.

Miyabe S., Fujinaga Y., Tsuchiya H., et al. TiO₂ nanotubes with customized diameters for local drug delivery systems. Journal of Biomedical Materials Research - Part B Applied Biomaterials 112, e35445 (2024); https://doi.org/10.1002/jbm.b.35445., In this study, we evaluated the drug release behavior of diameter customized TiO₂ nanotube layers fabricated by anodization with various applied voltage sequences: conventional constant applied potentials of 20 V (45 nm) and 60 V (80 nm), a 20/60 V stepped potential (50 nm [two-diameter]), and a 20–60 V swept potential (49 nm [full-tapered]) (values in parentheses indicate the inner tube diameter at the top part of nanotube layers). The structures of the 50 nm (two-diameter) and 49 nm (full-tapered) samples had smaller inner diameters at the top part of nanotube layers than that of the 80 nm sample, while the outer diameters at the bottom part of nanotube layers were almost the same size as the 80 nm sample. The 80 nm sample, which had the largest nanotube diameter and length, exhibited the greatest burst release, followed by the 50 nm (two-diameter), 49 nm (full-tapered), and 45 nm samples. The initial burst released drug amounts and release rates from the 50 nm (two-diameter) and 49 nm (full-tapered) samples were significantly suppressed by the smaller tube top. On the other hand, the largest proportion of the slow released drug amount to the total released drug amount was observed for the 50 nm (two-diameter) sample. Thus, 50 nm (two-diameter) achieved suppressed initial burst release and large storage capacity. Therefore, this study has, for the first time, applied TiO₂ nanotube layers with modulated diameters (two-diameter and full-tapered) to the realization of a localized drug delivery system (LDDS) with customized drug release properties.

In this study, we propose a simple approach to accelerate crack initiation in intergranular stress corrosion cracking (IGSCC) of Alloy 600 in a simulated pressurized water reactor (PWR) primary water environment. In addition, we perform three-dimensional crystallographic characterization of the crack initiation by electron backscatter diffraction (EBSD). Initiation of IGSCC of the alloy in the PWR primary environment was realized for a flat tensile specimen in a considerably short time through a slow strain rate test (SSRT). The accelerated initiation was attributed to the asperity of the alloy surface induced by mechano-chemical polishing with colloidal silica suspension before the SSRT was conducted. Following the SSRT, the specimen surfaces were covered with thick oxide films, which prevented EBSD measurements. The sputtering of thick oxide films enabled us to characterize cracks with EBSD, thus yielding important information on IGSCC. Finally, an approach for three-dimensional characterization of crack initiation is discussed.

The band structures and band gap energies, Eg, of passive films formed on titanium (Ti) in simulated bioliquids, Hanks’ solution (Hanks) and saline, were evaluated. Ti was polarized at 0, −0.1, and −0.2 VAg/AgCl, Ef, for 1 h. After polarization, the surfaces were characterized using X-ray photoelectron spectroscopy, and the photoelectrochemical responses were evaluated. The current change during photoirradiation was recorded as a photocurrent transient at each measuring potential, Em, and by changing the wavelength of the incident light. Passive films consisted of a very thin TiO2 layer containing small amounts of Ti2O3 and TiO, hydroxyl groups, and water. During polarization in Hanks, calcium and phosphate ions were incorporated or formed calcium phosphate but not in saline. Calcium phosphate and hydroxyl groups influenced the band structure. Eg was graded in Hanks but constant in saline, independent of Ef and Em. The passive film on Ti behaved as an n-type semiconductor containing two layers: an inner oxide layer with a large Eg and an outer hydroxide layer with a small Eg. In Hanks, Eg was 3.3–3.4 eV in the inner oxide layer and 2.9 eV in the outer hydroxide layer. In saline, Eg was 3.3 eV in the inner layer and 2.7 eV in the outer layer. Calcium phosphate and hydroxyl groups influenced the band structure of the passive film. The Eg of the outermost surface was smaller than that of TiO2 ceramics, which is probably one of the principles of the excellent biocompatibility of Ti among metals.

The band structures and band gap energies, Eg, of passive films formed on titanium (Ti) in simulated bioliquids, Hanks’ solution (Hanks) and saline, were evaluated. Ti was polarized at 0, −0.1, and −0.2 VAg/AgCl, Ef, for 1 h. After polarization, the surfaces were characterized using X-ray photoelectron spectroscopy, and the photoelectrochemical responses were evaluated. The current change during photoirradiation was recorded as a photocurrent transient at each measuring potential, Em, and by changing the wavelength of the incident light. Passive films consisted of a very thin TiO2 layer containing small amounts of Ti2O3 and TiO, hydroxyl groups, and water. During polarization in Hanks, calcium and phosphate ions were incorporated or formed calcium phosphate but not in saline. Calcium phosphate and hydroxyl groups influenced the band structure. Eg was graded in Hanks but constant in saline, independent of Ef and Em. The passive film on Ti behaved as an n-type semiconductor containing two layers: an inner oxide layer with a large Eg and an outer hydroxide layer with a small Eg. In Hanks, Eg was 3.3–3.4 eV in the inner oxide layer and 2.9 eV in the outer hydroxide layer. In saline, Eg was 3.3 eV in the inner layer and 2.7 eV in the outer layer. Calcium phosphate and hydroxyl groups influenced the band structure of the passive film. The Eg of the outermost surface was smaller than that of TiO2 ceramics, which is probably one of the principles of the excellent biocompatibility of Ti among metals.

Stress corrosion cracking (SCC) of pure copper in bentonite clay was examined using a slow strain rate test (SSRT). Bentonite was swollen with pure water or aqueous solutions containing NH₃ of 5 and 10 mM. Thick corrosion films and particulate deposits were formed on the copper surface after the SSRT. Typical tarnish rupture-type SCC occurred on pure copper in swollen bentonite with and without NH₃. The crack propagation rate was enhanced by NH₃. It is confirmed that a thick oxide layer was formed on copper during plastic deformation, resulting in tarnish crack-type SCC. Many particulate deposits observed on the surface were formed due to the rapid dissolution of Cu²⁺ ions to form porous CuO at local deformed sites, regardless of the SCC occurrence.