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11.
A method of dry grinding muscovite based on the use of knife-mills is reported. It was possible to produce mica with a particle size below 100 and 45 μm. After grinding, the samples were submitted to sonication treatment, which promoted delamination of the material. The particle size distribution shows that sonicated mica has more particles in the size range 10-50 μm than does non-sonicated mica have.This also indicates a decrease in the average particle size. Characterization of the treated muscovite by scanning electron microscopy revealed a highly delaminated material with a plate-like structure. The products were characterized by chemical analysis and X-ray diffraction, too. This mica has already been used for the synthesis of pearlescent pigments.  相似文献   
12.
Diverse microorganisms form complex microbial communities and usually exist in biofilm communities in both natural environments and engineered systems such as a wastewater treatment process. However, the conventional approach to investigate microbial ecology has not contributed to the understanding and clarification of the structure and function of biofilm communities. Some effective methods have been developed to investigate phylogenetic affiliations, metabolic activities and genetic activities in biofilm communities at the single-cell level. These techniques have been contributing to a better understanding of the spatial organization of biofilm communities and activities in engineered systems. However, further effort is needed to set out the general rules governing community development in biofilm communities and to advance the process performance of engineered systems. This review describes advances and limitations in methodology, particularly focusing on fluorescence in situ hybridization (FISH) and related techniques and the application of these methods to nitrifying biofilms in wastewater treatment processes.  相似文献   
13.
To develop hydrogenated amorphous carbon (a-C:H) as a biocompatible coating, a-C:H was studied in terms of its protein adsorption during the initial process of cell adsorption. A multilayer surface plasmon resonance (SPR) device consisting of an a-C:H layer on Au was built in the Kretschmann configuration to detect protein adsorption on an a-C:H film surface. From the dependence of reflectivity on the laser incident angle, SPR angle was determined to the incident angle in which the light intensity was reduced drastically. The proteins considered were lysozyme (Lyz) and fibrinogen (Fib). The SPR angle increased from 58.09 to 58.69° upon the adsorption of Lyz when the nonadsorbed Lyz was removed after introduction of 20 μM Lyz-containing solution. Upon the adsorption of Fib, the SPR angle increased from 60.95 to 61.76° when the nonadsorbed Fib were removed after the introduction of 0.4 μM Fib-containing solution. The shift in the SPR angle was small for both cases. Obtained results suggested that the number of adsorbed Lyz was higher than that of adsorbed Fib.  相似文献   
14.
The physiological roles of polyphosphates (polyP) recently found in arthropod mitochondria remain obscure. Here, the relationship between the mitochondrial membrane exopolyphosphatase (PPX) and the energy metabolism of hard tick Rhipicephalus microplus embryos are investigated. Mitochondrial respiration was activated by adenosine diphosphate using polyP as the only source of inorganic phosphate (P(i)) and this activation was much greater using polyP(3) than polyP(15). After mitochondrial subfractionation, most of the PPX activity was recovered in the membrane fraction and its kinetic analysis revealed that the affinity for polyP(3) was 10 times stronger than that for polyP(15). Membrane PPX activity was also increased in the presence of the respiratory substrate pyruvic acid and after addition of the protonophore carbonyl cyanide-p-trifluoromethoxyphenylhydrazone. Furthermore, these stimulatory effects disappeared upon addition of the cytochrome oxidase inhibitor potassium cyanide and the activity was completely inhibited by 20 μg/mL heparin. The activity was either increased or decreased by 50% upon addition of dithiothreitol or hydrogen peroxide, respectively, suggesting redox regulation. These results indicate a PPX activity that is regulated during mitochondrial respiration and that plays a role in adenosine-5'-triphosphate synthesis in hard tick embryos.  相似文献   
15.
Amorphous indium-gallium-zinc-oxide (a-IGZO) films were deposited by dc magnetron sputtering with H2O introduction and how the H2O partial pressure (PH2O) during the deposition affects the electrical properties of the films was investigated in detail. Resistivity of the a-IGZO films increased dramatically to over 2 × 105 Ωcm with increasing PH2O to 2.7 × 10− 2 Pa while the hydrogen concentration in the films increased to 2.0 × 1021 cm− 3. TFTs using a-IGZO channels deposited under PH2O at 1.6-8.6 × 10− 2 Pa exhibited a field-effect mobility of 1.4-3.0 cm2/Vs, subthreshold swing of 1.0-1.6 V/decade and on-off current ratio of 3.9 × 107-1.0 × 108.  相似文献   
16.
Functional nucleic acids with the capability of generating fluorescence in response to hybridization events, microenvironment or structural changes are valuable as structural probes and chemical sensors. We now demonstrate the enzyme-assisted preparation of nucleic acids possessing multiple thiazole orange (TO) dyes and their fluorescent behavior, that show a spectral change from the typical monomer emission to the excimer-type red-shifted emission. We found that the fluorescent response and emission wavelength of the TO dyes were dependent on both the state of the DNA structure (single- or double-stranded DNA) and the arrangement of the TO dyes. We showed that the fluorescent behavior of the TO dyes can be applied for the detection of RNA molecules, suggesting that our approach for preparing the fluorescent nucleic acids functionalized with multiple TO dyes could be useful to design a fluorescence bioimaging and detection technique of biomolecules.  相似文献   
17.
To achieve a rational insulation design for transformers, it is important to evaluate dielectric strength against surges actually impinging on equipment on‐site. This paper deals with the breakdown voltage characteristics of an oil gap under nonstandard lightning surge waveforms combined with oscillatory voltages. It is found that the breakdown voltages of the oil gap under nonstandard impulse waveforms are higher than standard lightning impulse voltages. The results can be ascribed to V–t characteristics of the oil gap in short‐time impulse voltage ranges. © 2003 Wiley Periodicals, Inc. Electr Eng Jpn, 146(3): 39–45, 2004; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10229  相似文献   
18.
Surgery has become one of the major treatments for lung cancer, increasing in number as well. Four times more patients undergo operation for lung cancer compared to 20 years age. The 5-years-survival rate of surgically treated patients this past 9 years was 55.2%. Technological advances in imaging and technical progress of diagnosis has lead to accurate staging prior to surgery. Group examination inables us to discover early lung cancer patients. Post operative adjuvant therapy such as LAK immunotherapy is also effective. The progress of extended surgery, surgical techniques such as bronchoplasty is also important. These factors are all responsible for the improvement of the survival rate for surgically treated patients.  相似文献   
19.
Poly(ester carbonate)s with different compositions were synthesized by bulk polycondensation of 1,4:3,6‐dianhydro‐D ‐glucitol with diphenyl sebacate and diphenyl carbonate in the presence of zinc acetate as a catalyst. Most of the poly(ester carbonate)s as well as the corresponding polycarbonate were amorphous, except the poly(ester carbonate) with a small carbonate content and the corresponding polyester, which are semicrystalline. All these poly(ester carbonate)s are soluble in chloroform, pyridine, dimethylformamide, dimethyl sulfoxide, and N,N‐dimethylacetamide. Soil burial degradation tests, biochemical oxygen demand (BOD) measurements in an activated sludge, and enzymatic degradation tests indicated that these poly(ester carbonate)s are potentially biodegradable. The biodegradability was found to be maximum for the poly(ester carbonate)s with carbonate contents of 10–20 mol % and to decrease markedly for the poly(ester carbonate)s with the carbonate content above 50 mol %. The biodegradability of the poly(ester carbonate)s is discussed in terms of the crystallinity, glass transition temperature, and surface hydrophobicity of the polymer films. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 872–880, 2002  相似文献   
20.
Appropriate nutrition is an essential prerequisite for effective improvement of athletic performance, conditioning, recovery from fatigue after exercise, and avoidance of injury. Nutritional supplements containing carbohydrates, proteins, vitamins, and minerals have been widely used in various sporting fields to provide a boost to the recommended daily allowance. In addition, several natural food components have been found to show physiological effects, and some of them are considered to be useful for promoting exercise performance or for prevention of injury. However, these foods should only be used when there is clear scientific evidence and with understanding of the physiological changes caused by exercise. This article describes various "functional foods" that have been reported to be effective for improving exercise performance or health promotion, along with the relevant physiological changes that occur during exercise.  相似文献   
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