Nepheline solid solutions having high thermal expansion coefficients ranging from 1.2 to 1.8×10−5°C−1 were prepared from the systems NaAlSiO4-LiAlSiO4 and NaAlSi4-KAlSiO4. The thermal expansion coefficient decreased by substituting Li+ for Na+, and increased by substituting K+ for Na+. By forming a series of the nepheline solid solutions in a single ceramic body, a functionally gradient material with respect
to thermal expansion was prepared. The thermal expansion coefficient should gradually vary with position according to the
composition x in Na1−x MxAlSiCO4 (M=Li and K). 相似文献
Experimental studies have been carried out on triggering characteristics of the SF6 discharge gap switch by use of XeCl excimer laser (wavelength = 308 nm). First, laser irradiation characteristics are studied on a pure SF6 in the pressure range of p = 160 ~ 3,800 torr. Using a lens of f (focal length) = 133 mm, the laser is irradiated into the gas, where the energy absorption is studied. If the laser is injected into the gas with the energy above a certain threshold for the breakdown, the rate of energy absorption is found to be ~ 17 percent of the incident energy at p > 760 torr. Injecting the laser into the SF6-filled gap switch (gap length = 7 mm, p = 760 torr), we have studied the triggering characteristics. Excellent triggering characteristics were obtained; delay time for the discharge ~ 20 ns, and the jitter ~ 260 ps when the gap voltage is operated at 99 percent of the self-breakdown voltage. In addition, the triggering characteristics are studied by changing the focusing point axially. It is found that both the delay time and the jitter decrease when the focusing point tends to approach the high-voltage electrodes. 相似文献
In two-thirds of patients with splenic lymphoma with villous lymphocytes (SLVL) a small amount of M-protein can be detected in association with the presence of plasma cells in the peripheral blood (PB) and/or bone marrow (BM). However, it is not known whether lymphoma cells and plasma cells originate from the same clone. In this report we describe a case of SLVL which was characterized by the presence of marked monoclonal gammopathy (IgG-kappa 90 g/l) and increased plasma cells in the BM. In an attempt to elucidate the origin of lymphoma cells and plasma cells, we performed morphological, cytogenetic and molecular studies on PB mononuclear cells (PBMNC) without plasma cells and BMMNC containing 10% plasma cells from this patient. Immunofluorescence showed that lymphoma cells and plasma cells were positive for cytoplasmic gamma heavy and kappa light chains. Well-developed endoplasmic reticulum was observed in the cytoplasmic organelles of PBMNC using an electron microscope. The mean IgG concentration in the 3 d supernatant cultures of PBMNC was 374 +/- 24 microg/l. More than 50% PBMNC differentiated into plasmacytoid cells in 6 d of liquid culture with IL-3 and IL-6. Analysis by two-colour FISH revealed that karyotypic abnormalities of monosomy X and trisomy 17 existed simultaneously in both lymphoma cells and plasma cells. JH gene rearranged bands from PBMNC and BMMNC by Southern blot hybridization were identical, whereas DNAs from PBMNC failed to hybridize with the Cmu probe. These observations strongly suggest that lymphoma cells and plasma cells originate from the same clone, and that plasma cells, as well as lymphoma cells, which have undergone class switch recombination, could produce IgG type M-protein in this case. 相似文献
Lately, the use of fibre reinforced thermoplastics (FRTP) has increased due to its increased mouldability compared to thermosetting FRP material.
FRTP includes stampable sheet, short and long fibre reinforced thermoplastic pellets, continuous fibre reinforced thermoplastics sheets, etc. The long fibre reinforced thermoplastic (LFRTP) pellet has better mechanical properties than short fibre reinforced pellets and better mouldability than stampable sheet. At present, injection moulding method is mainly used for moulding LFRTP pellets because of its high productivity.
However, the long fibre of LFRTP pellets, whose length is the same as pellet length, is degraded during processing if conventional injection moulding machines are used, and as a result, the mechanical properties are not improved as expected in many cases. Therefore, a new moulding process is required to make good use of LFRTP pellets.
For this study, a transfer moulding apparatus was designed and built to minimize fibre degradation of the moulded parts.
Firstly, the LFRTP pellets with fibre lengths of 3, 6, 9, 12.7 and 17 mm were prepared in order to clarify the difference of mechanical properties due to fibre length. The fibre ratio was 30% in weight for all cases and the same polypropylene was used. They were moulded to the shape of the test specimens. Tensile, bending and Izod impact strengths were measured by using these test specimens. Secondly, LFRTP pellets were moulded to the shape of test specimens by the transfer moulding apparatus and conventional injection moulding machine, and then mechanical properties were measured. At the same time, short fibre pellets were moulded to the smae shape of test specimens by the injection moulding machine, and mechanical properties were compared with those of LFRTP pellets.
With the long glass fibre reinforced polypropylene, good results of fibre preservation and mechanical properties were obtained by the transfer moulding apparatus which was built for this study. The impact strength was increased remarkably as the fibre length increased, and consequently the preservation of fibre length in the moulded parts was especially effective in improving the impact strength. 相似文献
A 79-year-old male with follicular thyroid carcinoma metastasizing to the lung, bone and lymph nodes was subjected to whole-body scintigraphy using technetium-99m tetrofosmin and 99mTc-sestamibi. Both agents delineated the metastatic lesions and the two image qualities were comparable. We believe that 99mTc-tetrofosmin and 99mTc-sestamibi images may be helpful in localizing metastatic foci and substitute for thallium-201 in the follow-up of patients with differentiated thyroid carcinoma. 相似文献
This paper presents a study on the effect of inhomogeneous compression of gas diffusion layer (GDL) caused by the channel/rib structure of flow-field plate. The experimentally evaluated properties are GDL intrusion into the channel, gas permeability, in-plane and through-plane bulk electric conductivities, and contact resistances at interfaces as a function of compressed thickness of GDL. It was found that the GDL is compressed very little under the channel whereas GDL under the rib is compressed to gasket thickness. The compression of GDL reduces gas permeability and contact resistance, and improves bulk conductivity. Hence, the inhomogeneous compression of GDL may lead into significant local variation of mass and charge transport properties in the GDL. These effects have been ignored in most of the published modeling studies. This contribution, part I, covers the experimental setup and measurement results, and a model which takes the inhomogeneous compression of GDL into account is presented in part II. 相似文献
A two-scale evaluation concept of remediation technologies for a contaminated site was expanded by introducing life cycle costing (LCC) and economic input-output life cycle assessment (EIO-LCA). The expanded evaluation index, the rescue number for soil (RNSOIL) with LCC and EIO-LCA, comprises two scales, such as risk-cost, risk-energy consumption or risk-CO2 emission of a remediation. The effectiveness of RNSOIL with LCC and EIO-LCA was examined in a typical contamination and remediation scenario in which dieldrin contaminated an agricultural field. Remediation was simulated using four technologies: disposal, high temperature thermal desorption, biopile and landfarming. Energy consumption and CO2 emission were determined from a life cycle inventory analysis using monetary-based intensity based on an input-output table. The values of RNSOIL based on risk-cost, risk-energy consumption and risk-CO2 emission were calculated, and then rankings of the candidates were compiled according to RNSOIL values. A comparison between three rankings showed the different ranking orders. The existence of differences in ranking order indicates that the scales would not have reciprocal compatibility for two-scale evaluation and that each scale should be used independently. The RNSOIL with LCA will be helpful in selecting a technology, provided an appropriate scale is determined. 相似文献
Abstract: Peptide mixtures prepared from soybean β‐conglycinin (7S‐peptides) were acylated with saturated fatty acids of different chain length (6C‐18C) in order to improve their antiviral activity against Feline calicivirus (FCV) strain F9 which is a typical norovirus surrogate. Among the fatty acids varieties, it was revealed that 7S‐peptides acylated with myristic and palmitic acids potently inhibited FCV replication. Myristorylation and palmitoylation of 7S‐peptides kept host cells viability at 91.51% and 98.90%, respectively. The infectivity of FCV on Crandell–Reese feline kidney cells was further determined after exposure of initial titer of 106.47 TCID50/mL. Myristoylated and palmitoylated 7S‐peptides significantly (P < 0.006) reduced FCV infectivity as compared to native 7S‐peptides. Native 7S‐peptides showed 25% FCV inhibitory activity while myristoylated and palmitoylated 7S‐peptides exhibited 98.59% and 99.98% reduction in FCV infectivity, respectively. Myristoylated and palmitoylated 7S‐peptides demonstrated higher anti‐FCV activity in a wide range of concentration with complete reduction at 25 μg/mL. Surface hydrophobicity was significantly (P < 0.05) increased after attachment of long hydrocarbon fatty acids to 7S‐peptides as supported by changes in fluorescence intensity. Enzymatic hydrolysis together with acylation will give an insight into surface and physiological functional lipopeptides derived from soy β‐conglycinin. 相似文献
The effect of inhomogeneous compression of GDL on the mass and charge transfer in PEMFC is studied. The model utilizes experimentally evaluated GDL parameters as a function of thickness. The modeling results are compared with a conventional model that excludes the effects. As a result, it is shown that the inhomogeneous compression has a significant effect on the current density distribution because of the varying contact resistance between GDL and electrode. This also implies that there are possible hot spots occurring inside the electrode, and thus inhomogeneous compression can have significant effects on the lifetime and local performance of the cell. According to the achieved results, the inhomogeneous compression of GDL cannot be neglected. 相似文献