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1.
Hydroliquefaction of low-sulfur Australian coals (Wandoan and Yallourn) was studied using iron carbonyl complexes as catalyst. The addition of Fe(CO)5 (2.8 wt% Fe of coal) increased coal conversion from 48.6 to 85.2% for Wandoan coal, and from 36.7 to 69.7% for Yallourn coal in 1-methylnaphthalene at 425°C under an initial hydrogen pressure of 50 kg cm?2. When molecular sulfur was added to iron carbonyls (Fe(CO)5, Fe2(CO)9 and Fe3(CO)12), higher coal converions ( > 92%) and higher oil yields (>46%) were obtained, along with an increase in the amount of hydrogen transferred to coal from the gas phase (0.2 to 2.8%, d.a.f. coal basis). In the liquefaction studies using a hydrogen donor solvent, tetralin, Fe(CO)5S catalyst increased the amount of hydrogen absorbed from the gaseous phase and decreased the amount of naphthalene dehydrogenated from tetralin. The direct hydrogen transfer reaction from molecular hydrogen to coal fragment radicals seems to be a major reaction pathway. Organic sulfur compounds, dimethyldisulfide and benzothiophene, and inorganic FeS2 and NiS were found to be good sulfur sources to Fe(CO)5. From X-ray diffraction analyses of liquefaction residues, it is concluded that Fe(CO)5 was converted into pyrrhotite (Fe1?xS) when sulfur was present, but into Fe3O4 in the absence of sulfur.  相似文献   
2.
LMR-UV (“low molecular weight resist for uv lithography”), a naphthoquinone-diazide sulfonic acid ester of a novolak resin, is a negative working resist. The mechanism of insolubilization of LMR-UV is based on the facts that the naphthoquinone-diazide moiety is decomposed to indenecarboxylic acid (polar compound) by photolysis upon UV irradiation and that the irradiated resist film insolubilizes in a non-polar developer. LMR-UV reliably forms 0.6 μm lines and spaces over a reflective substrate with steps by using a g-line stepper having a 0.35 NA lens. 0.6 μm-wide aluminum patterns over topography are obtained by use of g-line exposure and reactive ion etching. By use of an i-line aligner (NA = 0.42), LMR-UV resolves 0.25 μm space patterns with overhang profiles. The profiles are due to the large absorption coefficient of 3.8 μm?1. 0.3 μm wide aluminum patterns are formed by i-line exposure and lift-off metallization.  相似文献   
3.
The shape of interfaces formed by the contact of two liquid phases, immiscible with each other, and a gaseous phase can be predicted on the condition that the tension to work at each interface is known with a sufficient accuracy. In general, interfacial tension data available are not so accurate, however, as to be useful as they are in predicting the shape of interfaces, particularly when the spreading coefficient of either liquid (liquid 1) on the other (liquid 2) has a negative value of a small magnitude. Presented in this note is a simple method to rectify the interfacial tension data, with the aid of a measurement of the radius of a lens of liquid 1 of a known volume placed on the horizontal surface of liquid 2, and thereby make them usable for predicting interfacial geometries. The method is tested by applying it to benzene/water and n-pentane/water systems.  相似文献   
4.
Electrocodeposition of Sm and Co on a Cu substrate was investigated in a molten LiCl-KCl-SmCl3 (0.5 mol.%)-CoCl2 (0.1 mol.%) system at 723 K. Phase of the deposited Sm-Co alloys could be controlled by electrolysis potential. SmCo3 was formed on a Cu substrate by potentiostatic electrolysis in the potential range of 0.20-0.90 V (vs. Li+/Li). Sm2Co17 was obtained in the potential range of 0.90-1.50 V.  相似文献   
5.
The proportion of non-conforming items has been traditionally utilised as an evaluation criterion for quality of items. However, the proportion of non-conforming items is not necessarily useful as a proper evaluation criterion for controlling high-quality manufacturing in recent years. Accordingly, in order to achieve further quality improvement and innovation, more careful quality evaluation has been required newly. Then, a concept of quality loss in the Taguchi methods has been devised as a severe criterion of quality evaluation. Hereby, a variable single sampling plan having desired operating characteristics (OCs) indexed by quality loss has been proposed in the area of statistical quality control. By the way, the most economical sampling inspection in the average sample number (ASN) is the sequential sampling plan based on the Wald’s sequential probability ratio test. Then, from the viewpoint of cost reduction, we discuss a variable sequential sampling plan having desired OC indexed by quality loss with the aim of expansion of the utility of variable sampling plan for quality loss. As the result, the design procedure of the sequential sampling plan for satisfying some required design conditions indexed by quality loss is provided. In addition, the effectiveness of the proposed sequential sampling plan is verified through some numerical examples.  相似文献   
6.
A neural oscillator with a double-chain structure is one of the central pattern generator models used to simulate and understand rhythmic movements in living organisms. However, it is difficult to reproduce desired rhythmic signals by tuning an enormous number of parameters of neural oscillators. In this study, we propose an automatic tuning method consisting of two parts. The first involves tuning rules for both the time constants and the amplitude of the oscillatory outputs based on theoretical analyses of the relationship between parameters and outputs of the neural oscillators. The second involves an evolutionary tuning method with a two-step genetic algorithm (GA), consisting of a global GA and a local GA, for tuning parameters such as neural connection weights that have no exact tuning rule. Using numerical experiments, we confirmed that the proposed tuning method could successfully tune all parameters and generate sinusoidal waves. The tuning performance of the proposed method was less affected by factors such as the number of excitatory oscillators or the desired outputs. Furthermore, the proposed method was applied to the parameter-tuning problem of some types of artificial and biological wave reproduction and yielded optimal parameter values that generated complex rhythmic signals in Caenorhabditis elegans without trial and error.  相似文献   
7.
A novel chromatographic separation technique using a tertiary pyridine type resin has been applied to the partitioning of the trivalent actinides (An) and lanthanides (Ln) and several successful results have been shown. In an alcoholic hydrochloric acid system, the trivalent An were clearly separated from the Ln, while no such group separation was achieved in an alcoholic nitric acid system. On the other hand, the nitric acid system was more effective for the intragroup (i.e. individual) separation of the trivalent An and the Ln than the hydrochloric acid system. On the basis of these results, a novel concept for the partitioning of the trivalent An and Ln using the present separation technique and its flowchart have been proposed with its advantages and disadvantages.  相似文献   
8.
Flower-shaped crystals with diameters of 100–200 μm consisting of LaBGeO5 (LBGO) single crystals similar to petals were observed in the interior of transparent LBGO surface-crystallized glasses. Each flower-shaped crystal was radially grown from the surface of the included bubbles. A more intense second-harmonic generation was observed from the LBGO crystallized glasses with the flower-shaped LBGO single crystals compared to the samples without such crystals based on the Maker fringe technique and second-harmonic (SH) generation microscopy. The SH intensity for the flower-shaped LBGO single crystals monotonically decreased with increasing temperature up to 350 °C, less than the Curie temperature reported so far (530 °C). It is considered that the internal compressive stress induced by the difference in the thermal expansion between the LBGO single crystal and the corresponding glass affect the ferroelectric property of the flower-shaped LBGO single crystals in glass.  相似文献   
9.
Mucopolysaccharidoses (MPSs) constitute a heterogeneous group of lysosomal storage disorders characterized by the lysosomal accumulation of glycosaminoglycans (GAGs). Although lysosomal dysfunction is mainly affected, several cellular organelles such as mitochondria, endoplasmic reticulum, Golgi apparatus, and their related process are also impaired, leading to the activation of pathophysiological cascades. While supplying missing enzymes is the mainstream for the treatment of MPS, including enzyme replacement therapy (ERT), hematopoietic stem cell transplantation (HSCT), or gene therapy (GT), the use of modulators available to restore affected organelles for recovering cell homeostasis may be a simultaneous approach. This review summarizes the current knowledge about the cellular consequences of the lysosomal GAGs accumulation and discusses the use of potential modulators that can reestablish normal cell function beyond ERT-, HSCT-, or GT-based alternatives.  相似文献   
10.
MAGIC抛光方法及其研究进展   总被引:1,自引:0,他引:1  
MAGIC(MAGnetic Intelligent Compounds)是由包含磁性颗粒和磨粒的磁性流体固化形成的新型抛光材料。MAGIC中磁性颗粒形成的特殊排列可使磨粒均匀分布,因而MAGIC抛光可高效地获得小粗糙度的表面;另外,MAGIC可浇铸成形,故可用于复杂型面及狭小内表面的机械化抛光。简要介绍了MAGIC磨石的组成、制作方法、抛光效果以及目前的研究进展情况。  相似文献   
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