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81.
Journal of Thermal Analysis and Calorimetry - It is well known that cement production is not neutral for natural environment among others due to high CO2 emission. Different strategies of... 相似文献
82.
Rose Mary Michell Iwona Blaszczyk‐Lezak Carmen Mijangos Alejandro J. Müller 《Journal of Polymer Science.Polymer Physics》2014,52(18):1179-1194
In this article, a review of recent literature on confined crystallization within nanoporous anodic aluminum oxide (AAO) templates is presented. For almost all infiltrated polymeric materials, crystal orientation within the nanopores is a function of pore diameter. Tc and Tm usually decrease and are a function of pore size. When no pore interconnection remains, the crystallization occur at large supercoolings in heterogeneity free environments. Hence, the nucleation mechanism changes from heterogeneous to surface or homogeneous nucleation. The crystallization kinetics of infiltrated polymers should be close to first order, since in confined environments nucleation is the determining step of the overall crystallization and Avrami indexes (n) of ~1 (or lower in some cases) should be obtained. Examples are provided where these conditions have been met and first order kinetics (n = 1) were measured as opposed to higher orders (n = 3?4) for the same polymer in the bulk. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2014 , 52, 1179–1194 相似文献
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84.
Koltsov Iwona Prześniak-Welenc Marta Wojnarowicz Jacek Rogowska Anna Mizeracki Jan Malysa Maria Kimmel Giora 《Journal of Thermal Analysis and Calorimetry》2018,131(3):2273-2284
Journal of Thermal Analysis and Calorimetry - Industrially relevant nanopowder was synthesised by microwave hydrothermal synthesis to obtain well-controlled composition (ZrO2–AlO(OH) system)... 相似文献
85.
A series of tetrachloride platinum(IV) compounds of the general formulae PtCl4L2, where L = 1,2,4-triazolo[1,5-a]pyrimidine (tp) (1), 5,7-dimethyl-1,2,4-triazolo[1,5-a]pyrimidine (dmtp) (2), 5,7-ditertbutyl-1,2,4-triazolo[1,5-a]pyrimidine (dbtp) (3) and 5-methyl-1,2,4-triazolo[1,5-a]pyrimidin-7(4H)-one (HmtpO) (4) have been prepared and characterized by thermal analysis, 1H, 13C, 15N, 195Pt NMR and IR spectroscopy. Spectral data suggest that the triazolopyrimidines act as a monodentate ligand via the nitrogen atom N(3). The preliminary assessments of antitumor properties of the four complexes were evaluated as in vitro antiproliferative activity against three cell lines: HL-60 human acute promyelocytic leukemia, SW707 rectal adenocarcinoma and HCV29T bladder cancer. PtCl4(dbtp)2 exhibits high cytotoxic activity against all human cell lines, whereas the other complexes are only moderately active. 相似文献
86.
Bald I Dabkowska I Illenberger E Ingólfsson O 《Physical chemistry chemical physics : PCCP》2007,9(23):2983-2990
Low energy electron attachment (DEA) to hexafluoroacetone azine (HFAA) leads to a remarkable energy selective excision of CN(-) within a pronounced resonance located at 1.35 eV. The underlying dissociative electron attachment (DEA) reaction involves multiple bond cleavages and rearrangement within the neutral products. A series of further fragment ions (F(-), CF(3)(-), (CF(3))(2)C(-) and (CF(3))(2)CN(-)) are observed from resonant features above 2 eV and only (CF(3))(2)CN(-) is additionally formed within a narrow resonance below 1 eV. In contrast to CN(-) all the remaining fragment ions can be formed by simple bond cleavages with (CF(3))(2)CN(-) being the result of a symmetric decomposition of the target molecule by cleavage of the (N-N) bond with the excess charge localised on either of the identical fragments. Our ab initio calculations predict an adiabatic electron affinity of HFAA close to 2 eV with the geometry of the relaxed anion considerably distorted with respect to that of the neutral molecule. 相似文献
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88.
A series of polyacrylonitrile–dimethylsulfoxide–CuX2 (X=CF3SO3−, Cl−, Br−), films (foils) were prepared by means of the solution cast technique. The thickness of the foils was between 0.04 and 0.09 cm and they contained 70–80 wt.% of the solvent. Conductivities of the solid electrolytes were obtained from impedance measurements. The conductivity increases with the increase of the salt content up to 8 wt.%; at higher concentrations (>8 wt.%) the conductivity is more or less stable, and reaches, in the case of Cu(CF3SO3)2 and CuCl2, the level of ca. 10−3 Ω−1 cm−1 at room temperature. The foils based on the CuBr2 show even higher conductivity, close to 10−2 Ω−1 cm−1 at room temperature, a value comparable to that characteristic for liquid solutions. The temperature variation of the conductivity for all the systems studied is of the Arrhenius type. The activation energy, determined from linear plots lnσ=f(T−1), is of the order ca. 14 kJ mol−1 for the PAN/CuBr2/DMSO and of ca. 21 kJ mol−1 for the PAN/CuCl2/DMSO and the PAN/Cu(CF3SO3)2/DMSO systems. 相似文献
89.
Adam Tracz Jeremiasz Jeszka Iwona Kuciska Jean‐Paul Chapel Gisele Boiteux 《Macromolecular Symposia》2001,169(1):129-135
High density polyethylene (PE) was crystallised from the melt on freshly cleaved surface of highly oriented pyrolitic graphite (HOPG) or mica. Atomic force microscopy (AFM) studies of structure of the polymer surface adjacent to the graphite or mica were performed after peeling of from the substrate. Significant differences of crystalline structure on the interface were found between PE crystallised on graphite and mica. The surface of polyethylene crystallised on graphite shows large areas with regularly arranged rectangular structures. These objects (ca 20‐80 nm big) probably represent the nucleation centres of the lamellar growth. The surface of polyethylene crystallised at mica surface shows some dot‐like structures showing no particular arrangement. 相似文献
90.
Paulina Lewandowska Izabela Szczuka Iwona Bednarz-Misa Berenika M. Szczniak-Siga Katarzyna Neubauer Magdalena Mierzchaa-Pasierb Marek Zawadzki Wojciech Witkiewicz Magorzata Krzystek-Korpacka 《Molecules (Basel, Switzerland)》2021,26(23)
The mechanisms underlying the antineoplastic effects of oxicams have not been fully elucidated. We aimed to assess the effect of classic and novel oxicams on the expression/secretion of macrophage-associated chemokines (RTqPCR/Luminex xMAP) in colorectal adenocarcinoma cells, and on the expression of upstream the non-steroidal anti-inflammatory drug (NSAID)-activated genes NAG1, NFKBIA, MYD88, and RELA, as well as at the chemokine profiling in colorectal tumors. Meloxicam downregulated CCL4 9.9-fold, but otherwise the classic oxicams had a negligible/non-significant effect. Novel analogues with a thiazine ring substituted with arylpiperazine and benzoyl moieties significantly modulated chemokine expression to varying degree, upregulated NAG1 and NFKBIA, and downregulated MYD88. They inhibited CCL3 and CCL4, and their effect on CCL2 and CXCL2 depended on the dose and exposure. The propylene linker between thiazine and piperazine nitrogens and one arylpiperazine fluorine substituent characterized the most effective analogue. Only CCL19 and CXCL2 were not upregulated in tumors, nor was CXCL2 in tumor-adjacent tissue compared to normal mucosa. Compared to adjacent tissue, CCL4 and CXCL2 were upregulated, while CCL2, CCL8, and CCL19 were downregulated in tumors. Tumor CCL2 and CCL7 increased along with advancing T and CCL3, and CCL4 along with the N stage. The introduction of arylpiperazine and benzoyl moieties into the oxicam scaffold yields effective modulators of chemokine expression, which act by upregulating NAG1 and interfering with NF-κB signaling. 相似文献