检索结果-南通市图书馆

American Journal of Analytical Chemistry 2012年第10期3卷 683-692页

作者： Tetsuo Inui Atsuko kosuge Atsushi Ohbuchi kazuhiro Fujita Yuya Koike Masaru Kitano Toshihiro Nakamura Department of Applied Chemistry Meiji University Kawasaki Japan

A direct analysis method combining an iminodiacetate extraction disk (IED) with graphite furnace atomic absorption spectrometry was developed for the determination of Co, Ni, Cu, Cd, Sn, Pb, and Bi at sub-ppb levels in water. A 100 mL water sample was adjusted to pH 5.6 with nitric acid and a 1 mol?L–1 ammonium acetate solution, and then passed through an IED (diameter, 47 mm;effective filtering diameter, 35 mm) at a flow rate of 80 - 100 mL?min–1 to preconcentrate seven analytes. The IED was dried at 100?C for 20 min in an electric oven, and 110 - 145 small disks, each 2 mm in diameter, were punched out from the IED. A small disk was introduced into the graphite furnace and atomized according to a heating program. For Cd, Sn, Pb, and Bi measurements, Pd was used as a chemical modifier to enhance the absorbances. Calibration was performed using aqueous standard solutions. The detection limits, corresponding to three times the standard deviation (n = 5) of the blank values, were 0.092 μg·L–1 for Co, 0.12 μg·L–1 for Ni, 0.40 μg·L–1 for Cu, 0.077 μg·L–1 for Cd, 0.92 μg·L–1 for Sn, 0.61 μg·L–1 for Pb, and 0.80 μg·L–1 for Bi with an enrichment factor of 140 using a 100-mL water sample. A spike test for the seven analytes in tap water, rainwater, river water, and mineral drinking water showed quantitative recoveries (93% - 108%).

关键词： Water Sample Heavy Metal Preconcentration Iminodiacetate Extraction Disk Direct Introduction Technique Graphite Furnace Atomic Absorption Spectrometry

Aluminum Electroplating on AZ31 Magnesium Alloy with Acetic Anhydride Pretreatment

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Metallurgica Sinica(English Letters) 2022年第12期35卷 1996-2006页

作者： Zelei Zhang Atsushi Kitada kazuhiro Fukami Kuniaki Murase Department of Materials Science and Engineering Kyoto UniversityKyoto 606-8501Japan Department of Chemical System Engineering The University of TokyoTokyo 113-8656Japan

Magnesium(Mg)alloys for metal electroplating require a surface pretreatment,i.e.,the removal of the spontaneously oxidized surface layer(MgO,Mg(OH)_(2),andMgCO_(3)).However,the use of highly toxic and/or corrosive acids in conventional pretreatment processes has become an *** this study,a facile and less toxic pretreatment is demonstrated and applied in aluminum(Al)*** immersion of the AZ31 Mg alloy into acetic anhydride(Ac_(2)O)removed the spontaneously oxidized surface layer and formed a thin but stable magnesium acetate(Mg(OAc)_(2))layer that protects the metal substrate from further *** Al electroplating bath is a concentrated diglyme(G2)-AlCl_(3)organic solution that can readily dissolve Mg(OAc)_(2)to enable direct plating onto a metal *** as-deposited Al layer has a compact and crack-free morphology that improves the corrosion resistance and hardness(2.7 GPa).Owing to the lack of an interfacial oxidized layer,heat treatment led to the successful diff usion of Mg and Al atoms,which increased the hardness to 4.4 *** Ac_(2)O pretreatment of Mg alloys enables the successful Al electroplating and subsequent heat treatment.

关键词： Magnesium alloy Surface modifi cation Electrodeposition Hardness Corrosion resistance

Annealing,solvation,and mirror-plating effects in phosphonium chloroaluminate ionic liquids

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Nano Research 2023年第2期16卷 3348-3357页

The physicochemical properties of a specific ionic liquid(IL)are naturally considered to be constant at a given ***,a series of eutectic melts of trihexyl(tetradecyl)phosphonium chloride([P6,6,6,14]Cl)with aluminum chloride(AlCl3)is an *** viscosity of Al_(2)Cl_(7)−-dominated[P6,6,6,14]Cl–AlCl_(3)ILs(i.e.,AlCl_(3)mole fraction x=0.60–0.67)gradually increased as a function of *** also influenced the ultraviolet–visible spectra,nuclear magnetic resonance spectra,and the glass transition temperature of the *** annealing-induced variations in physicochemical properties were not observed in the AlCl4−-and Cl−-dominated *** particular,the ionic conductivities of the ILs(x=0.60–0.67)were strongly decoupled from their viscosities during *** initio calculations revealed the bending of the long tetradecyl chains in[P6,6,6,14]+coupled with Al_(2)Cl_(7)−,while neither Cl−nor AlCl_(4)−caused *** general,[P6,6,6,14]+-based ILs are recognized as sponge-like structures that consist of nano-scale polar and non-polar *** propose a gradual structurization process in Al_(2)Cl_(7)−-dominated ILs to account for their unusual physicochemical ***,the addition of tetradecane,solvated in the non-polar domains of the ILs,substantially reduced the viscosity of the structured IL with x=*** Al electroplating is possible without a brightener,using the x=0.67 ILs,regardless of annealing or the admixture of tetradecane.

关键词： ionic liquid physicochemical property ab initio calculation electrodeposition

Predicting Tensile Properties of Friction-Stir-Welded 6063 Aluminum with Experimentally Measured Welding Heat Input

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Metallurgica Sinica(English Letters) 2020年第9期33卷 1235-1242页

作者： Tianbo Zhao Yutaka SSato Hiroyuki Kokawa kazuhiro Ito Department of Materials Processing Graduate School of EngineeringTohoku University6-6-02 Aramaki-aza-AobaSendai 980-8579Japan Joining and Welding Research Institute Osaka UniversityMihogaoka11-1IbarakiOsaka 567-0047Japan Shanghai Key Laboratory of Materials Laser Processing and Modification School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China

This work aims to develop a reliable method to predict mechanical properties of friction-stir-welded 6 xxx-series alloys with experimentally measured welding heat input. A calorimetrical method was utilized to experimentally measure the welding heat input in the friction stir welded of aluminum alloy 6063-T5. Good correlations between the input variables, i.e., welding parameters and physical properties of the materials, and the welding heat inputs obtained with experimental measurements were discovered. The welding heat input can be predicted using the empirical equation derived based on these correlations. Moreover, the results suggested that the thermal conductivities of the welded alloys affected the welding heat input significantly. Mechanical properties, including hardness and tensile properties, of friction-stir-welded aluminum alloy 6063 were in good correlation to the heat input obtained with experimental measurement. These correlations were explained by the evolution of the strengthening precipitates during welding. This work proposed a reliable new route to predict these mechanical responses through the estimation of heat input.

关键词： Heat input Friction stir welding Calorimetrical Mechanical properties Hardness

Photophysics and electrochemistry relevant to photocatalytic water splitting involved at solid–electrolyte interfaces

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2017年第2期26卷 259-269页

作者： Tatsuya Shinagawa Zhen Cao Luigi Cavallo kazuhiro Takanabe King Abdullah University of Science and Technology(KAUST) KAUST Catalysis Center and Physical Sciences and Engineering Division(PSE)4700 KAUSTThuwal 23955-6900Saudi Arabia

Direct photon to chemical energy conversion using semiconductor–electrocatalyst–electrolyte interfaces has been extensively investigated for more than a half century. Many studies have focused on screening materials for efficient photocatalysis. Photocatalytic efficiency has been improved during this period but is not sufficient for industrial commercialization. Detailed elucidation on the photocatalytic water splitting process leads to consecutive six reaction steps with the fundamental parameters involved: The photocatalysis is initiated involving photophysics derived from various semiconductor properties(1: photon absorption, 2: exciton separation). The generated charge carriers need to be transferred to surfaces effectively utilizing the interfaces(3: carrier diffusion, 4: carrier transport). Consequently, electrocatalysis finishes the process by producing products on the surface(5: catalytic efficiency, 6: mass transfer of reactants and products). Successful photocatalytic water splitting requires the enhancement of efficiency at each stage. Most critically, a fundamental understanding of the interfacial phenomena is highly desired for establishing 'photocatalysis by design' concepts, where the kinetic bottleneck within a process is identified by further improving the specific properties of photocatalytic materials as opposed to blind material screening. Theoretical modeling using the identified quantitative parameters can effectively predict the theoretically attainable photon-conversion yields. This article provides an overview of the state-of-the-art theoretical understanding of interfacial problems mainly developed in our *** water splitting(especially hydrogen evolution on metal surfaces) was selected as a topic,and the photophysical and electrochemical processes that occur at semiconductor–metal, semiconductor–electrolyte and metal–electrolyte interfaces are discussed.

关键词： Photocatalysis Interface Water splitting Modeling Electrocatalysis Hydrogen evolution

Clinical analysis of primary anaplastic carcinoma of the small intestine

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2009年第5期15卷 526-530页

作者： Tsutomu Namikawa kazuhiro Hanazaki Department of Surgery Kochi Medical School Kohasu-Okocho Nankoku-City Kochi 783-8505 Japan

Primary anaplastic carcinoma is a rare variant of small intestinal cancer. Most reports of primary anaplastic carcinoma of the small intestine are isolated case reports, therefore the clinicopathological features, therapeutic management, and surgical outcome of this tumor type remain unclear. This review analyzes the available clinical characteristics of primary anaplastic carcinoma of the small intestine and investigates key differences from differentiated adenocarcinoma of the small intestine. A Medline search was performed using the keywords ＇small intestine＇ and ＇anaplastic carcinoma＇ or ＇undifferentiated carcinoma＇. Additional articles were obtained from references within the papers identified by the Medline search. The literature revealed a poor prognosis for patients who underwent surgical resection for anaplastic carcinoma of the small intestine, which gave a 3-year overall survival rate of 10.8% and a median survival time of 5.0 mo. The literature suggests that anaplastic carcinoma~ is markedly more aggressive than differentiated adenocarcinoma of the small intestine. Surgical resection with the aim of complete tumor removal provides the only beneficial therapeutic option for patients with anaplastic carcinoma of the small intestine, because chemotherapy and radiation therapy have no significant effect on the rate of survival. However, despite complete tumor resection, most patients with anaplastic carcinoma of the small intestine are at great risk of disease recurrence. Multicenter clinical trials are expected to provide additional therapeutic strategies and establish the efficacy of multimodality adjuvant therapy. This report also highlights the importance of a systematic diagnostic approach for anaplastic carcinoma of the small intestine.

关键词： Anaplastic carcinoma Small intestinalcancer Small intestinal tumor Operation Prognosis

Clinicopathological features of early gastric cancer with duodenal invasion

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2009年第19期15卷 2309-2313页

作者： Tsutomu Namikawa kazuhiro Hanazaki Department of Surgery Kochi Medical SchoolKohasu-OkochoNankoku-CityKochi 783-8505Japan

The incidence of early gastric cancer （EGC） with duodenal invasion is extremely low, although advanced gastric cancer that arises in the antrum occasionally invades the duodenum. We investigated the clinicopathological features of EGC with duodenal invasion and provided strategies for clinical management.A Medline search was performed using the keyword early gastric cancer＂ and ＂duodenal invasion＇： Additional articles were obtained from references within the papers identified by the Medline search. We revealed that EGC with duodenal invasion was of the superficial spreading type of tumor. Tumors 〉 60 mm in size invaded the duodenum more extensively, and the distance of duodenal invasion from the pyloric ring was further in the elevated type than in the depressed type of *** was no significant difference between the length of duodenal invasion and the histological type of the tumor. Gastric cancer located adjacent to the pyloric ring, even if cancer invasion was confined to the mucosa or submucosa, was more likely to invade the *** present study reveals that the elevated type of EGC is associated with more extensive duodenal invasion when the tumor size is 〉 60 ram, thus highlighting the importance of identification of duodenal invasion in these cases. We also reveal that sufficient duodenal resection with a cancer-free distal surgical margin should be performed in cases of duodenal invasion.

关键词： Duodenal invasion Early gastric cancer Gastrectomy Superficial spreading type Tumordifferentiation

Relationship between perioperative glycemic control and postoperative infections

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2009年第33期15卷 4122-4125页

作者： kazuhiro Hanazaki Hiromichi Maeda Takehiro Okabayashi Department of Surgery Kochi Medical SchoolKochi University

Perioperative hyperglycemia in critically ill surgery patients increases the risk of postoperative infection (POI), which is a common, and often costly, surgical complication. Hyperglycemia is associated with abnormalities in leukocyte function, including granulocyte adherence, impaired phagocytosis, delayed chemotaxis, and depressed bactericidal capacity. These leukocyte deficiencies are the cause ofinfection and improve with tight glycemic control, which leads to fewer POIs in critically ill surgical patients. Tight glycemic control, such as intensive insulin therapy, has a risk of hypoglycemia. In addition, the optimal targeted blood glucose range to reduce POI remains unknown. Since 2006, we have investigated tight perioperative blood glucose control using a closed-loop artificial endocrine pancreas system, to reduce POI and to avoid hypoglycemia. In this Topic Highlight, we review the relationship between perioperative glycemic control and POI, including the use of the artificial pancreas.

关键词： Glycemic control Surgical site infection Artificial pancreas Insulin therapy Glucose toxicity

Direct ethanol production from rice straw by coculture with two high-performing fungi

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Frontiers of Chemical Science and Engineering 2012年第2期6卷 139-145页

作者： Maki TAKANO kazuhiro HOSHINO Graduate School of Science and Engineering University of Toyama Toyama 930-8555 Japan

To develop efficient and economical direct ethanol production from fine rice straw crashed mechanically, two high-performing fungi, which can secret hyperactive cellulases and/or ferment effectively various sugars, were selected from some strains belong to Mucor circinelloides preserved in our laboratory. The simultaneous saccharification and fermentation （SSF） by coculture with these fungi was investigated. The screening of high- performing fungi resulted in the selection of NBRC 4572 as an ethanol-producing fungus and NBRC 5398 as a cellulase-secreting fungus. The strain 4572 produced ethanol aerobically from glucose and xylose in high yields of 0.420 g/g at 36 h and 0.478 g/g at 60 h, respectively, but secreted fairly low cellulases. On the other hand, the strain 5398 also produced ethanol from glucose in yield of 0.340 g/g though it had a little growth in xylose culture. However, it secreted hyperactive cellulases that are essential for hydrolysis of rice straw in culture and the maximum activities of endo-β-glucanase and β-glucosi- dase were 2.11 U/L and 1.47 U/L, respectively. In SSF of rice straw by coculture with two fungi selected, the ethanol production reached 1.28 g/L after 96 h when the inoculation ratio of the strain 5398 to the strain 4572 was 9.

关键词： Mucor circinelloides ethanol production cellulase secretion SSF coculture rice straw

Chemotherapy for advanced hepatocellular carcinoma in the sorafenib age

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2014年第15期20卷 4151-4159页

作者： Koji Miyahara kazuhiro Nouso Kazuhide Yamamoto Department of Gastroenterology and Hepatology Okayama University Graduate School of MedicineDentistryand Pharmaceutical SciencesOkayama-cityOkayama 700-8558Japan Department of Molecular Hepatology Okayama University Graduate School of MedicineDentistryand Pharmaceutical SciencesOkayama-cityOkayama 700-8558Japan

The kinase inhibitor sorafenib is the only systemic therapy proven to have a positive effect on survival of patients with advanced hepatocellular carcinoma(HCC).After development of sorafenib and its introduction as a therapeutic agent used in the clinic,several critical questions have been *** parameters and biomarkers predicting sorafenib efficacy are the most important issues that need to be *** it is difficult to know the responders in advance using conventional characteristics of patients,there are specific serum cytokines and/or gene amplification in tumor tissues that have been reported to predict efficacy of *** and benefits of continuation of sorafenib beyond radiological progression is another issue to consider because no other standard therapy for advanced HCC as yet *** addition,effectiveness of the expanded application of sorafenib is still controversial,although a few studies have shed some light on combinational treatment with sorafenib for intermediate-stage ***,over 50 relevant drugs have been developed and are currently under *** efficacy of some of these drugs has been extensively examined,but none have demonstrated any superiority over sorafenib,so ***,there are several drugs that have shown efficacy for treatment after sorafenib failure,and these are proceeding to further *** address these issues and questions,we have done extensive literature review and summarize the most current status of therapeutic application of sorafenib.

关键词： Biomarker Molecular targeted therapy Clinical trial Hepatic arterial infusion chemotherapy Hepatocellular carcinoma Sorafenib