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11.
Three North Dakota lignites with almost the same percentage carbon have been used to determine the relation between chemical structure and reactivity to hydrogenation. Average structural indices of the lignites were estimated using the pyridine-soluble products after alcohol-alkali treatment, the structural indices obtained at various reaction times being extrapolated to zero reaction time. Hydrogenation was influenced by the average structure, with the lignite having higher aromaticity, higher molecular weight of the pyridine extract from the alcohol-alkali reaction product, larger aromatic ring size and lower content of aliphatic structure, showing a smaller degree of conversion.  相似文献   
12.
The cellulose binding domain (CBD) of cellulosome-integrating protein A from Clostridium thermocellum NBRC 103400 was genetically fused to FMN-dependent NADH-azoreductase (AZR) and glucose 1-dehydrogenase (GDH) from Bacillus subtilis. The fusion enzymes, AZR-CBD and CBD-GDH, were expressed in Escherichia coli Rosetta-gami B (DE3). The enzymes were purified from cell-free extracts, and the specific activity of AZR-CBD was 15.1 U/mg and that of CBD-GDH was 22.6 U/mg. AZR-CBD and CBD-GDH bound strongly to 0.5 % swollen cellulose at approximately 95 and 98 % of the initial protein amounts, respectively. After immobilization onto the swollen cellulose, AZR-CBD and CBD-GDH retained their catalytic activity. Both enzymes bound weakly to 0.5 % microcrystalline cellulose, but the addition of a high concentration of microcrystalline cellulose (10 %) improved the binding rate of both enzymes. A reactor for flow injection analysis was filled with microcrystalline cellulose-immobilized AZR-CBD and CBD-GDH. This flow injection analysis system was successfully applied for the determination of glucose, and a linear calibration curve was observed in the range of approximately 0.16–2.5 mM glucose, with a correlation coefficient, r, of 0.998.  相似文献   
13.
The arc welding has been used in various welding methods because it is inexpensive and high in strength after welding. However, it is a problem that accidents such as collapse of the bridge occur because of the welding defects. The welding of low cost and high productivity is required without the welding defects. The pulsed TIG welding is inexpensive and capable of high‐quality welding. The electromagnetic force contributing to penetration changes because the transient response of arc temperature and iron vapor generated from anode occurs. However, the analysis of pulsed TIG welding with metal vapor has been elucidated only metal vapor concentration near anode with transient phenomenon and heat flux. Thus, the theoretical elucidation of penetration depth with control factor has not been researched. In this paper, the contribution of metal vapor mass at the periphery part of pulsed arc to the electromagnetic force in the weld pool is elucidated. As a result, the iron vapor mass at periphery part decreased with increasing the frequency. The iron vapor was stagnated at axial center within one cycle. The electromagnetic force to the penetration depth direction in weld pool increased at axial center. Therefore, the metal vapor mass at periphery part plays an important role for the electromagnetic force increment at axial center.  相似文献   
14.
ABSTRACT

Absorbed-dose estimation is essential for evaluation of the radiation tolerance of minor-actinide-separation processes. We propose a dose-evaluation method based on radiation permeability, with comparisons of heterogeneous structures seen in the solvent-extraction process, such as emulsions forming in the mixture of the organic and aqueous phases. A demonstration of radiation-energy-transfer simulation is performed with a focus on the minor-actinide-recovery process from high-level liquid waste with the aid of the Monte Carlo radiation-transport code PHITS. The simulation results indicate that the dose absorbed by the extraction solvent from alpha radiation depends upon the emulsion structure, and that from beta and gamma radiation depends upon the mixer-settler-apparatus size. Non-negligible contributions of well-permeable gamma rays were indicated in terms of the plant operation of the minor-actinide-separation process.  相似文献   
15.
Fanor Mondragon  Koji Ouchi 《Fuel》1984,63(7):973-977
Model compound studies were carried out to elucidate the reaction mechanisms taking place during the liquefaction of coal with the hydrogen produced from the reaction of zinc and water. In compounds of the type Ph-(CH2)n-Ph the splitting of the aliphatic bridge was easier with higher n values. Ether type compounds such as diphenylether were unreactive although the C-O bond in dibenzylether was easily cleaved. Condensed ring aromatic compounds gave low conversion with hydrogenation being facilitated by an increase in ring number. Phenolic compounds such as phenol did not react well, but the reactivity increased with increase in aromatic ring size. The cleavage of the aliphatic bridge was accelerated by the OH group, for example, in the case of 4-hydroxydiphenylmethane bond scission was about 15 times higher than that of diphenylmethane. Heterocyclic compounds were unreactive.  相似文献   
16.
ABSTRACT: In this study, we focused on the antihypertensive effect of newly fermented salt-free soy sauce (SFS) in spontaneously hypertensive rats (SHRs). A 13-wk oral administration of SFS was performed daily in 8- to 21-wk-old SHRs with a dose of 200 mg/kg of body weight/d. The systolic (SBP) and diastolic (DBP) blood pressures were measured for each week during the experimental period. As a result, a significant (P < 0.01) BP lowering effect was observed from the 5th d to the end of the experiment in the SFS group compared with the control group (ΔSBP21-wk: 27 mmHg, ΔDBP21-wk: 20 mmHg). In contrast to such substantial effect by SFS intake, angiotensin I-converting enzyme activities in blood and local organs as well as pharmaceutical parameters such as serum Na+ or K+ level did not show any significant difference between in both SFS and control groups. Vasoconstriction experiment using thoracic aorta rings from 21-wk SHRs provided an interesting result that the rings from the SFS group evoked a >2-fold higher increase in the angiotensin II-stimulated constrictive response compared with the rings from the control group (P = 0.012), which suggested that the SFS-intake would be effective in possessing a higher vessel tone. Practical Application: In this study, we investigated the antihypertensive effect of newly fermented SFS in SHRs. As a result of 13-wk SFS-administration, we found a significant antihypertensive effect of the SFS. This finding strongly demonstrates that the developed SFS would be greatly beneficial for health and useful for health-related industries.  相似文献   
17.
K. Kanai  Y. Ouchi 《Thin solid films》2009,517(11):3276-17035
Modification of quasi two-dimensional surface electron system on Au(111) with adsorption of long-chain n-alkane molecule n-CH3(CH2)42CH3 (tetratetracontane: TTC) was investigated by angle-resolved photoemission spectroscopy. Significant modification of the energy band structure of the Shockley surface state was induced by the adsorption of TTC monolayer with “flat-on” structure. The energy shift of the Shockley surface state toward the Fermi level reaches about 160 meV at Γ? point (k = 0 Å− 1). The possible origin of the stabilization of the surface electron system with TTC monolayer is discussed.  相似文献   
18.
The structural, electrochemical, and gas phase hydrogen storage properties of predominantly C14 crystalline phase alloys with partial replacement by Co (up to 2.5 at%) are reported. Minor phases, including C15 and cubic TiNi, were found by X-ray diffraction and contributed to the improved hydrogen diffusion through the alloy. The optimal Co-content of between 1.0 and 1.5 at% provides easy activation, high gas phase capacity, and a high discharge capacity. An optimized alloy formula also provided the smallest metallic nickel cluster size embedded in the surface oxide and the largest number of nickel clusters. In sealed cell studies, a Co-content of 1.5% gives the best performance in formation, cycle life, and charge retention, but has worse specific power and low temperature performance than some other compositions. The high-rate dischargeabilities at lower rates were found to be limited by surface reactions, not bulk diffusion.  相似文献   
19.
To understand the adsorption properties of a styrene–divinylbenzene copolymer functionalized with N,N,N-trimethylglycine, AMP03, the adsorption behaviours for platinoid ions (Ru(III), Rh(III) and Pd(II)) were examined. Furthermore, we performed adsorption experiments using sample solutions by adding triethylamine, thiourea and N,N,N-trimethylglycine. Based on the adsorption data obtained in this study, we performed chromatographic experiments. The results indicated that all platinoid ions in the feed solution completely adsorbed on AMP03, and almost 80% of the adsorbed platinoid ions were recovered. These results show that AMP03 has the potential to recover Ru(III), Rh(III) and Pd(II) from high-level liquid waste.  相似文献   
20.
In aging societies, such as that of Japan, there is growing awareness that robotic technology has the potential to help both physical and mental labor. To take an example of mental labor, the robotic technology can contribute as an interface to home electric appliances and a conversation partner with interactive communication. In this case, it is important to recognize the elderly user’s activities for not only watching-over services but also improving the quality of the conversation. We propose a low-throughput recognition method for in-home living activity recognition using only off-the-shelf sensors, namely an accelerometer and a microphone, which are commonly applied in mobile phones. The system can determine whether the user is walking, quiet, or performing a task by acceleration sensing, and then in the latter case, acoustic sensing can be used to classify the nature of the task that the user is performing. We conducted two experiments to confirm the feasibility of the proposed method. As a result of the first experiment, three movement conditions are classified with more than 95?% accuracy by acceleration sensing: walking, quiet, or performing a task. And it classified the nature of the task into brushing teeth, shaving, drying the hair with a hairdryer, flushing the toilet, vacuuming, washing the dishes, and ironing with 75.8?% accuracy by acoustic sensing and improved the accuracy to 85.9?% by training with only the subject’s own data. Moreover, the result of the second experiment shows that it is effective to adopt instance-based recognition which is an additional recognition scheme per each continuous task, according to the assumed application.  相似文献   
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