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1.
The structure and rheological properties of binary blends of polycarbonate (PC) and polystyrene (PS) were investigated using various PS samples with different molecular weights, namely PS1k (Mw = 1,000), PS53k (Mw = 53,000), and PS240k (Mw = 240,000). The blends with PS53k and PS240k show phase-separated structures, whereas the blend with PS1k is miscible. The shear viscosity decreases greatly on addition of PS53k and PS240k, especially at high shear rates, which would be a great advantage at processing operations. Because the nonlinear response occurs in the small strain region for multilayered films of PC and PS240k, the origin of the significant viscosity drop for the phase-separated system is interfacial slippage at the phase boundary.  相似文献   
2.
The effect of xylan propionate (XylPr) as a novel biomass‐derived nucleating agent on the poly(lactide) sterecomplex was investigated. Addition of XylPr to an enantiomeric blend of poly(l ‐lactide) (PLLA) and poly(d ‐lactide) (PDLA) was performed in either the solution state or molten state. The solution blend of PLLA/PDLA with XylPr was prepared by mixing equal volumes of 1 wt% XylPr/PLLA and 1 wt% XylPr/PDLA solutions in chloroform and precipitating in methanol. The solution blend with XylPr showed shorter half‐time crystallization than the solution blend without XylPr in isothermal crystallization between 80 and 140 °C, although homocrystallization occurred. Enhanced stereocomplex crystallization in the solution blend with XylPr was observed at 180 °C, where no crystallization occurred in the solution blend without XylPr. Addition of XylPr to PLLA/PDLA blend in the molten state was performed at 240 °C. Thereafter, the melt blend of PLLA/PDLA with or without XylPr was either quenched in iced water or isothermally crystallized directly from the melt. Isothermal crystallization of the melt‐quenched blend with XylPr gave a similar result to the solution blend with XylPr. In contrast, the melt‐crystallized blend with XylPr formed only stereocomplex crystals after crystallization above 140 °C. Furthermore, the melt‐crystallized blend with XylPr showed a higher crystallinity index and melting temperature than the melt‐crystallized blend without XylPr. This shows that XylPr promotes stereocomplex crystallization only when the blend of PLLA/PDLA with XylPr is directly crystallized from the molten state just after blending. © 2016 Society of Chemical Industry  相似文献   
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For the development of micro- and nano-technology, it has been strongly desired to understand thermo-fluid phenomena inside or around micro- and nano-devices. An optical measurement technique based on the absorption and the emission of photons by molecules is useful for experimental analyses of thermo-fluid phenomena of micro and nanoflows. The pressure-sensitive paint (PSP) technique is a potential diagnostic tool for pressure measurements of micro/nano gas flows because it works as a so-called “molecular sensor”. However, the micro-scale measurement of PSP has been limited by the aggregation of the luminescent molecules and their thick film due to the use of a polymer binder. In our previous work, we adopted the Langmuir–Blodgett (LB) technique to fabricate pressure-sensitive molecular film (PSMF) with ordered molecular assemblies, and investigated properties of PSMF. In this study, a novel approach to enhance the luminescent intensity of PSMF is proposed, and the pressure distribution in a micro-nozzle is successfully measured by using PSMF. Moreover, we compared the pressure distribution measured by PSMF with that numerically analyzed by the direct simulation monte carlo (DSMC) method, showing good agreement with each other.  相似文献   
5.
A case of bilateral hypernephroma treated by right heminephrectomy in situ and "benchwork" excision of two tumors from the left kidney followed by autotransplantation is presented. Follow-up examination has demonstrated good renal function with no evidence of tumor recurrence or metastasis. This case illustrates the feasibility of benchwork operation and its application to renal tumors, particularly when these tumors are bilateral and preservation of renal tissue is imperative. Long-term follow-up of patients managed by this technique is mandatory.  相似文献   
6.
Mechanisms of hydrogen sulfide removal with steel making slag   总被引:1,自引:0,他引:1  
In the present study, we experimentally investigated the removal of hydrogen sulfide using steel-making slag (SMS) and clarified the mechanism of hydrogen sulfide removal with the SMS. The results proved that SMS is able to remove hydrogen sulfide dissolved in water, and the maximum removal amount of hydrogen sulfide per unit weight of the SMS for 8 days was estimated to be 37.5 mg S/g. The removal processes of hydrogen sulfide were not only adsorption onto the SMS, but oxidation and precipitation as sulfur. The chemical forms of sulfide adsorbed onto the SMS were estimated to be sulfur and manganese sulfide in the ratio of 81% and 19%, respectively. It is demonstrated here that the SMS is a promising material to remediate organically enriched coastal sediments in terms of removal of hydrogen sulfide. Furthermore, using SMS is expected to contribute to development of a recycling-oriented society.  相似文献   
7.
Pearlescent pigments are one of the most essential materials not only in paints, plastics, and printing inks, but also in cosmetics. Pigments with higher chroma, color purity, and brightness are in high demand all over the world. In this study we developed a high chroma pearlescent pigment for powder foundation. To produce the high chroma pearlescent pigment, we have designed the layer structure of a pearlescent pigment using computer simulation. In the simulation we have considered its layer structure, the complex refractive indices of the layers, and the thickness distribution of a mica substrate that was measured with Atomic Force Microscopy (AFM). The layer thicknesses have been optimized. The feature of this design is that iron oxide having selective light absorption has been adopted as the layer material to enhance certain wavelengths of the reflected light, which is one of the properties of high chroma. Thus, we have found that a mica substrate homogeneously coated with iron oxide which is further coated with colorless titanium dioxide has a high chroma compared to ordinary pearlescent pigments. The designed pigment has been synthesized by developing a novel manufacturing method to achieve a low roughness iron-oxide surface. We believe that this simulation is useful for designing other pearlescent pigments.  相似文献   
8.
Dyeing wastewater collected in Kyoto city, Japan, was investigated for the occurrence of aryl hydrocarbon receptor (AhR) ligands by using an AhR-responsive reporter gene assay. Concentrated extracts of wastewater samples elicited a dose-dependent increase in AhR ligand activity, and several hydrophobic HPLC fractions of the extracts were highly effective in inducing AhR ligand activity. Three potential AhR ligands were isolated from these fractions and identified to be Disperse Red 92, Disperse Yellow 64, and 3'-hydroxybenzo[b]quinophthalone by using HPLC and LC-MS/MS. Disperse Red 92, which has also been detected in the treated effluent from a sewage plant receiving the wastewater, is an anthraquinone disperse dye showing weak AhR binding affinity in the assay. Disperse Yellow 64 and 3'-hydroxybenzo[b]quinophthalone are quinoline disperse dyes capable of activating the AhR at nanomolar concentrations. In particular, Disperse Yellow 64 is a highly potent AhR ligand that was 3 times more effective in inducing AhR ligand activity than beta-naphthoflavone in the assay. Quinoline disperse dyes are suggested to be a new class of xenobiotic AhR ligands which pose a danger to aquatic biota and human health.  相似文献   
9.
A method for reconstructing the three-dimensional coronary arterial tree structure from biplane two-dimensional angiographic images is presented. This method exploits the geometrical mathematics of X-ray imaging and the tracking of leading edges of injected contrast material into each vessel for identification of corresponding points on two images taken from orthogonal views. Accurate spatial position and dimension of each vessel in three-dimensional space can be obtained by this reconstruction procedure. The reconstructed arterial configuration is displayed as a shaded surface model, which can be viewed from various angles. Such three-dimensional vascular information provides accurate and reproducible measurements of vascular morphology and function. Flow measurements are obtained by tracking the leading edge of contrast material down the three-dimensional arterial tree. A quantitative analysis of coronary stenosis based on transverse area narrowing and regional blood flow, including the effect of vasoactive drugs, is described. Reconstruction experiments on actual angiographic images of the human coronary artery yield encouraging results toward a realization of computer-assisted three-dimensional quantitative angiography.  相似文献   
10.
62-year-old woman admitted our hospital with pain of left upper extremity from the left chest and dysphasia. Chest X-ray showed the huge mass shadow in the left lung field. Diabetes mellitus and inflammatory reaction such as high fervor, leukocytosis, CRP and ESR accentuation were recognized. Conservative therapy was done at first, but mass shadow on X-ray increased, and swelling appeared from the neck to the left lateral chest wall. And the same site appeared like subcutaneous emphysema. Computed Tomography showed mass shadow which was enlarged and spread in lung parenchyma and left chest wall with bubble image. Incision and open drainage was performed for the left chest wall but origin bacteria was detected in neither anaerobic nor aerobic culture of pus. Inflammation and mass shadow of left upper lung field have decreased gradually. The patient discharged without bronchoalveolar fistula. Abscess extending from the neck or chest wall with diabetes mellitus is very rare.  相似文献   
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