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Poly[vinylidenefluoride‐co‐(tetrafluoroethylene)] (P(VDF‐TeFE)) exhibited clear spherulitic texture with negative birefringence. The number and growth rates of the spherulites decreased at high crystallization temperature than at low crystallization temperature. Nonetheless, overall larger spherulites were found at high crystallization temperature and the brightness of the spherulites increased very fast at low crystallization temperature, thereafter it seemed as diminution of birefringence. AFM was used to investigate the impact of organo modified nanodiamond(ND) on spherulitic textures, lamellar thickness, and thickness distribution of P(VDF‐TeFE) copolymer. Poly[ethylene‐co‐(tetrafluoroethylene)] (ETFE) also confirmed spherulites structure and the boundaries could be clearly observed. By incorporation of the organo modified nanodiamond (ND) and organo‐modified montmorillonite (MMT) in fluropolymer matrix, it was found that spherulitic texture was seriously disordered and their nanohybrids was found only to have poorly developed spherulite structure. Both of the nanohybrids samples show better crystallization temperature as compared to their neat copolymer samples. Furthermore, the incorporation of nanoparticles decreased the size of the spherulites. POLYM. ENG. SCI., 57:161–171, 2017. © 2016 Society of Plastics Engineers  相似文献   
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Obesity-related metabolic abnormalities, including adipokine imbalance and chronic inflammation, are involved in liver carcinogenesis. Chemerin, a novel adipokine, plays a critical role in adipogenesis, energy metabolism, and inflammation. We evaluated the impact of serum chemerin levels on liver functional reserves in hepatocellular carcinoma (HCC) patients and on the recurrence and prognosis of HCC. This study included 44 patients with any stage of HCC who underwent curative treatment at Gifu Municipal Hospital (Gifu, Japan) between 2006 and 2007. Recurrence-free survival and overall survival were estimated using the Kaplan-Meier method. Serum albumin levels (Pearson’s correlation coefficient; r = 0.3110, p = 0.0399), platelet counts (r = 0.4159, p = 0.0050), and prothrombin times (r = 0.3775, p = 0.0115) were significantly correlated with serum chemerin levels in patients with HCC, and they were inversely correlated with Child-Pugh scores (r = −0.3732, p = 0.0126), serum alanine aminotransferase levels (r = −0.3864, p = 0.0105), and total bilirubin levels (r = −0.4023, p = 0.0068). Among these variables, a multiple comparison test identified that platelet counts and total bilirubin levels were associated with serum chemerin levels (p < 0.0083). No significant correlation was found between serum chemerin levels and recurrence-free survival (p = 0.3691) or overall survival (p = 0.7916). In HCC patients, serum chemerin concentrations were correlated with liver functional reserves and platelet counts, but not with recurrence or prognosis.  相似文献   
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The lithiation of 5,5′‐dibromo‐2,2′‐bithiophene with one equivalent of an alkyllithium such as n‐BuLi or s‐BuLi was studied by varying the residence time in flow microreactors. With a short residence time, the product 2,2′‐bithiophene (3) derived from dilithiation was obtained preferentially and a significant amount of the starting material 5,5′‐dibromo‐2,2′‐bithiophene remained unchanged. An increase in the residence time caused a higher yield of the product 5‐bromo‐2,2′‐bithiophene derived from monolithiation with expense in the yields of 2,2′‐bithiophene and 5,5′‐dibromo‐2,2′‐bithiophene. The lithiation using MeLi gave the product 5‐bromo‐2,2′‐bithiophene preferentially even with a very short residence time.  相似文献   
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It is thought that the adjustment of intraspecific aggression is an essential factor in the development of a social structure. To understand the natural laws for organizing the social structure, we focus on the fighting behavior of crickets, Gryllus bimaculatus, and investigate the neuronal mechanisms to adjust aggressiveness associated with a neuromodulatory biological amine: serotonin (5-HT).In this paper, we present a working theory of a neurophysiological mechanism based on the past biological studies on the 5-HT hypothesis, and a mathematical model of the mechanism. We analyzed this model and concluded that this neurophysiological mechanism makes the forgetting process slower. Next, we fitted our theoretical forgetting curve to an experimental curve and estimated the parameters of our model. These estimated values were in agreement with common belief in biological science.  相似文献   
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Electron-rich, side chain alkynes of an aromatic polyamine were functionalized by a [2+2] cycloaddition, followed by retro-cyclization with the electron-accepting 7,7,8,8-tetracyanoquinodimethane (TCNQ). 1H NMR studies were used to optimize the reaction conditions. Mild heating to >50?°C afforded the postfunctionalized aromatic polyamines with the desired acceptor amounts. The quantitative TCNQ addition was demonstrated by the MALDI-TOF mass spectrum and elemental analysis. Introduction of the cyano-based acceptor moieties into the polymer side chains resulted in unusually strong intermolecular interactions. In addition to the ?ШC?? interactions of the extended acceptor moieties, these intermolecular forces were supposed to improve the thermal stability of the aromatic polymers. Furthermore, the donor?Cacceptor chromophores formed by this postfunctionalization displayed low energy charge-transfer bands and redox activities in both the anodic and cathodic directions. The straightforward postfunctionalization technique using the alkyne?CTCNQ addition is useful for the preparation of narrow band gap polymers in one step.  相似文献   
80.
(The microstructural refinement of cobalt-based alloy (Stellite No. 6) by laser cladding and friction stir processing (FSP) was studied. A nanometer-sized microstructure consisting of fine carbide (particle size: 100–200 nm) and a grain (grain size: 150–250 nm) was successfully fabricated by the FSP on the laser clad cobalt-based alloy. The nanostructured cobalt-based alloy (Stellite No. 6) had an extremely high hardness of about 750 HV.  相似文献   
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