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881.
The Mg-S-I thermochemical water-splitting cycle, consisting of: (i) redox reaction of sulfur dioxide and iodine with magnesium oxide in aqueous phase; (ii) hydrolysis of magnesium iodide; (iii) thermal decomposition of magnesium sulfate; and (iv) thermal dissociation of hydrogen iodide, was studied. Based on the fundamental studies on each of the constituent reactions, the whole cycle was demonstrated on a laboratory scale by constructing an apparatus and by the repeated operations of chemical reactions and circulation of reactants through purely thermochemical processes below 1000°C. Electric furnaces and quartz glass reactors were used. With satisfactory performance of the system, 38 times of cycle operations were successfully repeated with roughly constant production of 0.3 liter of H2 and 0.15 liter of O2 per cycle. The time requirement for one cycle operation was about 1 h, where all the chemical reactions proceeded and all the reactants were circulated. 相似文献
882.
Since the first discovery of fullerenes in 1985, the insertion of one or more atoms into a hollow fullerene cage has been attempted. Furthermore, synthesis and extraction of metallofullerene, La@C(n), were reported in 1991. Recent successful isolation and purification of metallofullerenes have facilitated the investigation of their chemical properties. This mini-review presents a summary of the recent progress of chemical functionalization and supramolecular chemistry of M@C(82). Selective functionalization and successful structural analysis of derivatives have revealed their chemical features arising from endohedral metal doping. 相似文献
883.
Isao?TsuyumotoEmail author Yuichiro?Miura Masato?Nirei Shota?Ikurumi Takenori?Kumagai 《Journal of Materials Science》2011,46(16):5371-5377
Mixture of starch and amorphous sodium polyborate (SPB) is found to show high flame retardancy, when its aqueous solution
is deposited and dried on organic polymer materials such as polyethylene terephthalate (PET) nonwoven, rigid polyurethane
(RPU) foam, and polypropylene (PP) nonwoven. The PET nonwoven (10 mm thickness) and the RPU foam (10 mm thickness) coated
with the mixture endure the premixed flame of butane gas burner with length of 100 mm for more than 12 min. The PP nonwoven
(0.7 mm thickness) endures the nonpremixed flame with length of 65 mm in the 45 degrees Meckel burner test for more than 2 min.
The backside temperatures in the both tests remain below 130 °C. The thermal analyses and the SEM observation indicate the
mechanism that the SPB foam promotes the carbonization of starch and that the carbonized layer together with the SPB foam
insulate inside from oxygen and heat. 相似文献
884.
Lysine methyl ester (LME), which was generated in situ by the reaction of lysine methyl ester dihydrochloride and triethylamine in dimethyl sulfoxide (DMSO), was prepolymerized with 4,4′‐bismaleimidodiphenylmethane (BMI) at 80°C for 2 h in DMSO. Then, the formed prepolymer was precipitated in water. The obtained LME/BMI prepolymers with molar ratios of 2:2, 2:3, and 2:4 were compression‐molded at a final temperature of 230°C for 2 h to produce cured lysine methyl ester/4,4′‐bismaleimidodiphenylmethane resins (cLBs; cLB22, cLB23, and cLB24, respectively). Fourier transform infrared (FTIR) analyses revealed that the Michael addition reaction of amino groups to the C?C bonds of the maleimide group occurred in addition to the homopolymerization of the maleimide group. The glass‐transition temperature (Tg) and 5% weight loss temperature (T5) of the cured resin increased with increasing BMI feed content, and cLB24 showed the highest Tg (343°C) and T5 (389°C). The flexural strengths (131–150 MPa) and moduli (3.0–3.6 GPa) of the cLBs were comparable to those of the conventionally cured resins of BMI and 4,4′‐diaminodiphenylmethane. Field emission scanning electron microscopy analysis revealed that there was no phase separation for all of the cured resins. Although cLB23 and cLB24 were not biodegradable, cLB22 had a biodegradability of 8.5% after 30 days in an aerobic aqueous medium containing activated sludge. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40379. 相似文献
885.
Females of the lichen moth, Miltochrista calamina (Arctiidae, Lithosiinae), were previously shown to produce 5-methylheptadecan-7-ol (1) as a sex pheromone. In field tests, males were attracted only by the (5R,7R)-isomer of the four stereoisomers that were prepared by separation from two mixtures of diastereoisomers. A new route to (5R,7R)-1 starting from (S)-propylene oxide was developed utilizing the SN2 reaction of an optically active secondary tosylate and the Jacobsen hydrolytic kinetic resolution of an epoxide intermediate as key steps. Enantioselective HPLC analysis of the product and the antipode synthesized from (R)-propylene oxide confirmed their high enantiomeric excess (> 99 %). Using this stereospecific synthesis, six analogues with the same configuration as (5R,7R)-1 but with different alkyl chain(s) connected to the stereogenic centers were prepared in order to obtain GC/MS data and to examine the ability of M. calamina males to discriminate between them. The mass spectra of the synthetic analogues revealed characteristic fragment ions derived by cleavage around the methyl group in addition to that at the hydroxyl group. In field trapping tests, five out of the six compounds were attractive to male M. calamina moths, indicating that the males distinguished the configurations of methyl and hydroxyl groups but were less able to perceive differences in the lengths of the two alkyl chains in the pheromone. 相似文献
886.
Cancer is one of the most common causes of death worldwide. Along with the advances in diagnostic technology achieved through industry–academia partnerships, the survival rate of cancer patients has improved dramatically through treatments that include surgery, radiation therapy, and pharmacotherapy. This has increased the population of cancer “survivors” and made cancer survivorship an important part of life for patients. The senses of taste and smell during swallowing and cachexia play important roles in dysphagia associated with nutritional disorders in cancer patients. Cancerous lesions in the brain can cause dysphagia. Taste and smell disorders that contribute to swallowing can worsen or develop because of pharmacotherapy or radiation therapy; metabolic or central nervous system damage due to cachexia, sarcopenia, or inflammation can also cause dysphagia. As the causes of eating disorders in cancer patients are complex and involve multiple factors, cancer patients require a multifaceted and long-term approach by the medical care team. 相似文献
887.
888.
Hidehiro Nakano Yu Taguchi Yuta Kanamori Akihide Utani Arata Miyauchi Hisao Yamamoto 《IEEJ Transactions on Electrical and Electronic Engineering》2012,7(Z1):S52-S58
In this paper, a simple competitive particle swarm optimizer for finding plural acceptable solutions is proposed. In the proposed algorithm, particles are divided into plural groups corresponding to the required number of solutions. The groups simultaneously search for solutions in their own priority search regions. These regions prevent the different groups from searching for the same solutions. The proposed algorithm can effectively find desired plural acceptable solutions without introducing complex judgments for convergences to each solution and without increasing the number of search iterations. Also, the proposed algorithm can easily control distances between these solutions by adjusting a single additional parameter. Through numerical experiments, the effectiveness of the proposed algorithm is verified. In addition, the proposed algorithm is applied to a problem in wireless sensor networks. It is shown that obtained results can contribute to prolonging lifetime of such networks. © 2012 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献
889.
Asano R Sone Y Ikoma K Hayashi H Nakanishi T Umetsu M Katayose Y Unno M Kudo T Kumagai I 《Protein engineering, design & selection : PEDS》2008,21(10):597-603
We report the utility of in vitro refolding in the preparation of monomorphous hEx3 bispecific diabodies with epidermal growth factor receptor and CD3 retargeting from insoluble aggregates in Escherichia coli. Appropriate interaction between cognate variable heavy and light chains led to the formation of functional hEx3 heterodimers in a diabody format rather than inactive homodimers. The refolded hEx3 was found to exhibit almost the equivalent activity to the hEx3 and single-chain hEx3 (hEx3-scDb) prepared in a mammalian secretion system. We suggest that the preparation of hEx3 from bacterial insoluble material by means of in vitro refolding would be useful for industrial-scale production of the diabody for its potential use in clinical studies. 相似文献
890.
Anyun Zhang Chunmei Chen Etsushu Kuraoka Mikio Kumagai 《Separation and Purification Technology》2008,62(2):407-414
4,4′,(5′)-Di-(tert-butylcyclohexano)-18-crown-6(DtBuCH18C6) is a chelating agent having high selectivity mostly for Sr(II). To significantly reduce its leakage by molecular modification, a macroporous silica-based DtBuCH18C6 polymeric composite (DtDo/SiO2–P) was synthesized. It was performed by impregnating and immobilizing DtBuCH18C6 and 1-dodecanol molecules into the pores of the SiO2–P particles utilizing an advanced vacuum sucking technique. The adsorption of a few fission and non-fission products Sr(II), Ba(II), Cs(I), Ru(III), Mo(VI), Na(I), K(I), Pd(II), La(III), and Y(III) onto DtDo/SiO2–P was investigated. It was done by examining the effects of contact time and the HNO3 concentration in a range of 0.1–5.0 M at 298 K. At the optimum concentration of 2.0 M HNO3, DtDo/SiO2–P exhibited strong adsorption ability and high selectivity for Sr(II) great over all of the tested elements, which showed very weak or almost no adsorption except Ba(II). Meanwhile, It was found that the quantity of total organic carbon (TOC) leaked from DtDo/SiO2–P in 2.0 M HNO3, 187.5 ppm, was lower than 658.4 ppm that leaked from DtBuCH18C6/SiO2–P, which was not modified. This was ascribed to the effective association of DtBuCH18C6 and 1-dodecanol through intermolecular interaction. The reduction of DtBuCH18C6 leakage by molecular modification with 1-dodecanol was achieved. It was of great benefit to application of DtDo/SiO2–P in chromatographic partitioning of Sr(II), one of the main heat generators, from high level liquid waste (HLLW) in reprocessing of nuclear spent fuel in the MAREC (Minor Actinides Recovery from HLLW by Extraction Chromatography) process developed recently. 相似文献