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1.
Polymers (Basel) ; 14(19)2022 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-36235897

RESUMO

The quantitative relationship between the fraction of UV exposure energy and the retention fraction of tensile strength was investigated on the m-Aramid/p-Aramid blend ratio of spun yarn. An exponential equation to calculate tensile strength from an arbitrary UV exposure energy is evaluated for yarns and fabrics. The spun yarns were exposed to UV light using a xenon-arc weathering meter. The retention fraction of tensile strength decreased exponentially with increasing the fraction of UV exposure energy. Curve fitting of the retention fraction of tensile strength to the fraction of UV exposure energy revealed two groups of degradation coefficients based on the blending ratio of m-Aramid/p-Aramid. The correlation between the degradation coefficients (αy and αf) of spun yarn and fabrics can be linearly regressed. The constant of proportionality in linear regression is considered to be the gap between the structure and the breaking mechanism of the fabric relative to yarn breakage. Based on the correlation between the degradation coefficients of spun yarn and fabrics and a mathematical model of the tensile strength of the spun yarn, the tensile strength of fabrics at a given UV exposure energy can be estimated from the tensile strength of the yarn.

2.
Polymers (Basel) ; 14(16)2022 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-36015496

RESUMO

This study focused on the m-Aramid/p-Aramid blend ratio of the fabrics, clarified the quantitative relationship between UV exposure and strength retention, and developed a mathematical model to calculate tensile strength from an arbitrary amount of UV exposure energy. The results of tensile strength tests before and after UV exposure showed that the decrease in tensile strength due to UV degradation depended on the combination of p-Aramid and m-Aramid blend percentages. Tensile strength for all blend ratios decreased exponentially with UV exposure energy and was within the range of results for fabrics with p-Aramid 100% and m-Aramid 100%. The retention fraction of tensile strength, which represents the tensile strength after UV exposure relative to the initial tensile strength, decreased exponentially with increasing the fraction of UV exposure energy for all fabrics used in this study. Fitting the retention fraction of tensile strength to the fraction of UV exposure energy, two groups of fabrics were classified based on m-Aramid blends of 40% or more and 60% or less. This model can predict the tensile strength of firefighter clothing fabrics that retain high mechanical strength when exposed to UV light and design the strength of firefighter clothing with consideration of degradation over time.

3.
Sci Rep ; 7(1): 15516, 2017 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-29138478

RESUMO

Neutron diffractometry has been a critical tool for clarifying spin structures. In contrast, little attention has been paid to neutron transmission spectroscopy, even though they are different types of the same phenomenon. Soon, it will be possible to measure the wavelength dependence of transmissions easily using accelerator-driven neutron facilities. Therefore, we have started studying the potential of spectroscopy in magnetism, and in this paper, we report the first observation of a magnetic Bragg dip and Bragg edge in the neutron transmission spectra of a typical spin superstructure; clear antiferromagnetic Bragg dips and Bragg edges are found for a single crystal and powder of nickel oxide, respectively. The obtained results show that transmission spectroscopy is a promising tool for measurements under multi-extreme conditions and for the precise analyses of spin structures, not only in MW-class pulsed spallation source facilities but also in compact neutron source facilities.

4.
J Hazard Mater ; 287: 151-61, 2015 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-25644031

RESUMO

To reduce greenhouse gas emissions, which contribute to global warming, production of gasoline blended with ethyl tert-buthyl ether (ETBE) is increasing annually. The flash point of ETBE is higher than that of gasoline, and blending ETBE into gasoline will change the flash point and the vapor pressure. Therefore, it is expected that the fire hazard caused by ETBE-blended gasoline would differ from that caused by normal gasoline. The aim of this study was to acquire the knowledge required for estimating the fire hazard of ETBE-blended gasoline. Supposing that ETBE-blended gasoline was a two-component mixture of gasoline and ETBE, we developed a prediction model that describes the vapor pressure and flash point of ETBE-blended gasoline in an arbitrary ETBE blending ratio. We chose 8-component hydrocarbon mixture as a model gasoline, and defined the relation between molar mass of gasoline and mass loss fraction. We measured the changes in the vapor pressure and flash point of gasoline by blending ETBE and evaporation, and compared the predicted values with the measured values in order to verify the prediction model. The calculated values of vapor pressures and flash points corresponded well to the measured values. Thus, we confirmed that the change in the evaporation characteristics of ETBE-blended gasoline by evaporation could be predicted by the proposed model. Furthermore, the vapor pressure constants of ETBE-blended gasoline were obtained by the model, and then the distillation curves were developed.


Assuntos
Etil-Éteres/química , Gasolina/estatística & dados numéricos , Pentanos/química , Tolueno/química , Volatilização
5.
J Nanosci Nanotechnol ; 12(6): 5016-20, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22905569

RESUMO

Two-dimensional (2-D) magnetic field dependences of Niobium/niobium tunnel junction current Ic were first used in order to measure the magnetic field near the superconducting film. The 2-D magnetic field dependences of superconducting Josephson current Ic through the niobium/niobium tunnel junction can be changed by the external magnetic field. So, we measured the magnetic field using this superconducting tunnel junction fabricated by DC-magnetron apparatus as a magnetic sensor. The 2-D magnetic field dependences of Ic through the junction without and with the Nb thin-film sample were compared. With the Nb thin-film sample, extension of the characteristics in the perpendicular direction Hz to the sample was observed because of the Meissner effect of the superconducting thin-film sample. Moreover, the magnetic field Hz perpendicular to the Nb thin-film sample has been added in the triangle shape as a following sequence: (0)-(1000)-(0)-(2000)-(0)-(3000)-(0)-(4000)-(0)-(5000 A/m)-(0). Significant changes in the measured Ic-H (Hy,Hz) characteristics were observed above the certain value of Hz > 3000 A/m. We consider the shift of the measured Ic-H dependence in the Hz minus direction occurred because of the flux quanta were trapped in the sample superconducting niobium film after the Hz value had been added greater than 3000 A/m.


Assuntos
Condutometria/instrumentação , Membranas Artificiais , Nióbio/química , Radiometria/instrumentação , Semicondutores , Condutividade Elétrica , Desenho de Equipamento , Análise de Falha de Equipamento , Campos Magnéticos
6.
J Nanosci Nanotechnol ; 12(6): 5021-4, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22905570

RESUMO

Perpendicular magnetic field dependences of the Josephson current through tunnel junction were first measured. Niobium/aluminum-oxide/niobium (200/5/150 nm in thickness) superconducting tunnel junctions were fabricated by DC-magnetron apparatus with a load-lock chamber. Josephson current Ic through the superconducting junction is usually changed by the external magnetic field in one direction to check the barrier uniformity. To obtain more information of the barrier uniformity, we have changed the external magnetic field in two directions (Hx and Hy: parallel field to the junction plane) parallel to the junction plane. The shape of Ic-Hx curve and Ic-Hy curve were the Fraunhofer pattern in the Ic-Hx-Hy dependence of the junction with uniform barrier. This Ic-Hx-Hy dependence has no hysteresis. In this study, we have first applied the external magnetic field Hz perpendicular to the junction plane and have obtained Ic-Hz characteristics using three pairs of Helmholtz coils. In the case that the perpendicular field Hz < 2400 A/m, the Ic-Hz characteristics have a little hysteresis. The shape of Ic-Hz characteristics was similar to the Fraunhofer pattern. In the case that the perpendicular field Hz > 2400 A/m, the Ic-Hz characteristics have strong hysteresis. The Josephson current Ic always disappeared in the case that Hz > 7000 A/m. Two recovering methods of this current Ic were (a) alternating Hz field and (b) heating the sample to the room temperature and again cooling to the liquid He temperature.


Assuntos
Nióbio/química , Nióbio/efeitos da radiação , Semicondutores , Campos Eletromagnéticos , Campos Magnéticos
7.
Hematol Rep ; 3(2): e10, 2011 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-22184531

RESUMO

Waldenström's macroglobulinemia (WM)/ lymphoplasmacytic lymphoma (LPL) is an indolent mature B-cell neoplasm. In rare cases of WM/LPL, diffuse large B-cell lymphoma (DLBCL) develops as a result of histologic transformation. In this report, we present a case of DLBCL developing in a patient with WM/LPL. Combination chemotherapy for DLBCL was effective and complete remission was eventually achieved. We attempted to determine the clonal relatedness between WM/LPL and DLBCL in the patient by analyzing complementarity-determining region 3 (CDR3) in the immunoglobulin heavy chain gene. A common CDR3 sequence was found in tumor cells of DLBCL and those of WM/LPL, indicating that tumor cells of DLBCL are clonally identical to those of WM/LPL. Therefore, in the present case, DLBCL is developed from WM/LPL cells by clonal evolution.

8.
Int J Hematol ; 93(5): 618-623, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21523339

RESUMO

The correlation between imatinib (IM) trough plasma concentration (Cmin) and clinical response was assessed in patients with chronic-phase chronic myeloid leukemia. The Cmin correlated with neither the achievement of complete cytogenetic response (977 vs. 993 ng/ml, P = 0.48) nor a major molecular response (1,044 vs. 818 ng/ml, P = 0.17). Although this was significantly higher in patients with complete molecular response (CMR) than in those without (1,430 vs. 859 ng/ml, P = 0.04), the difference was not significant in the sub-population treated with a standard dose of IM (400 mg/day). Finally, multivariate analysis showed that the IM standard dose, but not Cmin, was predictive of the achievement of CMR. We thus suggest that, in practical clinics at least, adherence to the standard dose is the most important factor for the achievement of CMR.


Assuntos
Proteínas de Fusão bcr-abl/antagonistas & inibidores , Leucemia Mieloide de Fase Crônica/sangue , Leucemia Mieloide de Fase Crônica/tratamento farmacológico , Piperazinas/farmacocinética , Inibidores de Proteínas Quinases/farmacocinética , Proteínas Tirosina Quinases/antagonistas & inibidores , Pirimidinas/farmacocinética , Idoso , Benzamidas , Estudos Transversais , Análise Citogenética , Relação Dose-Resposta a Droga , Cálculos da Dosagem de Medicamento , Feminino , Proteínas de Fusão bcr-abl/sangue , Proteínas de Fusão bcr-abl/genética , Humanos , Mesilato de Imatinib , Hibridização in Situ Fluorescente , Japão , Leucemia Mieloide de Fase Crônica/patologia , Masculino , Pessoa de Meia-Idade , Piperazinas/administração & dosagem , Inibidores de Proteínas Quinases/administração & dosagem , Proteínas Tirosina Quinases/sangue , Proteínas Tirosina Quinases/genética , Pirimidinas/administração & dosagem , Indução de Remissão/métodos , Estudos Retrospectivos , Resultado do Tratamento
9.
Cancer Genet Cytogenet ; 134(1): 60-4, 2002 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-11996798

RESUMO

We report a case of acute myeloid leukemia with tetrasomy 21 as the sole chromosome abnormality in a constitutionally normal patient. Tetrasomy 21 was observed at presentation, disappeared in remission, but reappeared in recurrence of the disease. Fluorescence in situ hybridization analysis using a probe specific for the AML1 gene showed four distinct signals in 82.4% and three signals in 10.8% of interphase nuclei, although conventional G-banding revealed tetrasomy 21 alone in mosaicism with normal karyotype. Spectral karyotyping further confirmed the presence of extra copies of chromosome 21. Tetrasomy 21 as the only anomaly is relatively rare in patients with hematologic disorders other than Down syndrome, and to our knowledge has been reported previously in only seven cases. In a review of the literature, tetrasomy 21 as the only anomaly may be associated with myeloid disorders, although simultaneous numeric abnormalities other than chromosome 21 have been reported in acute lymphoblastic leukemia with hyperdiploid karyotype.


Assuntos
Aneuploidia , Cromossomos Humanos Par 21/genética , Leucemia Mieloide Aguda/genética , Proteínas Proto-Oncogênicas , Adulto , Subunidade alfa 2 de Fator de Ligação ao Core , Proteínas de Ligação a DNA/genética , Diagnóstico Diferencial , Feminino , Humanos , Hibridização in Situ Fluorescente , Cariotipagem , Leucemia Mieloide Aguda/patologia , Leucemia Mielomonocítica Aguda/genética , Leucemia Mielomonocítica Aguda/patologia , Fatores de Transcrição/genética
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