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Slim Salhi Jihen Mahfoudh Souhir Abid Leonard‐Ionut Atanase Marcel Popa Christelle Delaite 《Polymer International》2020,69(11):1161-1168
A series of random polyesteramides (PEAs) with a range of molar composition from 90/10 to 50/50 were synthesized by direct melt polycondensation of ε‐caprolactone and l ‐alanine. Their structure was fully characterized by Fourier transform IR and NMR spectroscopy. The resulting copolymers are completely amorphous with the exception of PEA‐90/10 which possesses a semicrystalline structure. These PEAs present increasing glass transition temperatures at increasing l ‐alanine contents and exhibit fairly good thermal stability with 10% mass loss temperatures reaching 315 °C. © 2020 Society of Industrial Chemistry 相似文献
3.
Lingfeng Zhou Zhipeng Zeng Michael P. Brady Donovan N. Leonard Harry M. Meyer Yukinori Yamamoto Wenyuan Li Greg Collins Xingbo Liu 《International Journal of Hydrogen Energy》2021,46(41):21619-21633
The chromium (Cr) evaporation behavior of several different types of iron (Fe)-based AFA alloys and benchmark Cr2O3-forming Fe-based 310 and Ni-based 625 alloys was investigated for 500 h exposures at 800 °C to 900 °C in air with 10% H2O. The Cr evaporation rates from alumina-forming austenitic (AFA) alloys were ~5 to 35 times lower than that of the Cr2O3-forming alloys depending on alloy and temperature. The Cr evaporation behavior was correlated with extensive characterization of the chemistry and microstructure of the oxide scales, which also revealed a degree of quartz tube Si contamination during the test. Long-term oxidation kinetics were also assessed at 800 to 1000 °C for up to 10,000 h in air with 10% H2O to provide further guidance for SOFC BOP component alloy selection. 相似文献
4.
William Leonard Scott C. Hutchings Robyn D. Warner Zhongxiang Fang 《International Journal of Food Science & Technology》2019,54(5):1849-1857
The effects of incorporating lupin flour on the physicochemical and sensory characteristics of beef sausages were explored. Lupin (Lupinus angustifolius) flour was roasted, then hydrated to match the moisture content of beef meat. The beef sausage samples were manufactured for six treatments by replacing beef with hydrated lupin flour from 0% to 36% (w/w). Proximate analysis revealed that carbohydrate (dietary fibre) level was increased from 9.62% to 19.31%, whereas fat content was decreased from 11.62% to 7.91%. Inclusion of lupin flour increased the meat emulsion stability (fluid released decreased from 9.35% to 1.53%) and decreased cooking loss from 22.70% to 14.30%. Softer texture and greater adhesiveness were observed in lupin-incorporated formulations. Sensory evaluation indicated no significant difference between control and 12% lupin-enriched beef sausage formulation in appearance, aroma, flavour and overall liking, suggesting lupin flour can be added to beef sausage at this level without compromising consumer acceptance. 相似文献
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Leonard Jeff Harris Kruti Patel Michael Martin 《International journal of molecular sciences》2020,21(22)
The most common type of non-Hodgkin lymphoma in adults is diffuse large B-cell (DLBCL). There is a historical unmet need for more effective therapies in the 2nd and 3rd line setting. Emerging immunochemotherapies have shown activity in small studies of heavily pre-treated patients with prolonged remissions achieved in some patients. Anti-CD19 CAR (chimeric antigen receptor) T cells are potentially curative in the 3rd line and beyond setting and are under investigation in earlier lines of therapy. Antibody-drug conjugates (ADC’s) such as polatuzumab vedotin targeting the pan-B-cell marker CD79b has proven effectiveness in multiply-relapsed DLBCL patients. Tafasitamab (MOR208) is an anti-CD19 monoclonal antibody producing prolonged remissions when combined with Lenalidomide (LEN) in patients who were not candidates for salvage chemotherapy or autologous stem cell transplant. Selinexor, an oral, small-molecule selective inhibitor of XPO1-mediated nuclear export (SINE), demonstrated prolonged activity against heavily-pretreated DLBCL without cumulative toxicity and is being investigated as part of an oral, chemotherapy-free regimen for relapsed aggressive lymphoma. This article reviews current strategies and novel therapies for relapsed/refractory DLBCL. 相似文献
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Leonard B. Richardson Dennis T. Burton Ronald M. Block Ann M. Stavola 《Water research》1983,17(2):205-213
Adult white perch (Morone americana), acclimated to 15°C, were exposed to a series of ozone-produced oxidant (OPO) concentrations for 96 h using continuous flow bioassay techniques. Toxicity data were analyzed using both response surface modeling and standard probit regression. White perch were also exposed to a series of near and sublethal OPO concentrations, selected from the acute toxicity study, for 96 h and then placed in clean non-ozonated water for 14 days. Blood pH, hematocrit and gill histopathology were analyzed during exposure at 24, 48 and 96 h and after 4 and 14 days in the recovery period. Blood pH and hematocrit levels were analyzed statistically using standard ANOVA and multiple range tests. Histopathological effects were examined using both light microscopy and scanning electron microscopy. The 24-, 48- and 96-h LC30's were 0.38, 0.26 and 0.20 mg OPO l−1, respectively. Blood pH was significantly reduced at concentrations 0.15 mg OPO l−1 but not at 0.10 mg l−1 or lower concentrations. Hematocrit significantly increased at concentrations 0.10 mg OPO l−1. Histopathological examination revealed minimal effects on gill tissue at 0.01 mg OPO l−1, moderate epithelial sloughing and heavy mucus production at 0.05 mg OPO l−1 and extreme tissue damage at concentrations 0.10 mg l−1. Results from both the acute toxicity and the exposure and recovery study were compared with the effects of chlorine-produced oxidants (CPO) obtained from the literature. Both OPO and CPO appear to have similar effects on adult white perch. 相似文献
10.
Robert H. Scanlan Leonard J. Fortier 《Journal of Wind Engineering & Industrial Aerodynamics》1982,9(3):207-236
Time histories of the fluctuating wind pressure differential across the shell of a full-scale cooling tower were measured in 1974 by Princeton University personnel. Data were recorded around a single level, at the throat, at a height of ~100 m. A set of simultaneous three-minute records from these data is examined statistically in the present paper. The methods employed include spectral and correlation analyses, plus parametric time-series characterization of the data.Aside from its direct engineering interest as an aid in defining dynamic wind-loading conditions, the fluctuating flow activity around the tower throat may be interpreted as a fair example of turbulent flow about a rough circular cylinder at a Reynolds number approaching 108. This aspect is emphasized in the present paper. In this situation the relation of the spectrum of the incident wind to pressure spectra about the cylindrical section may be of interest in connection with theories of the deformation of turbulence by bluff bodies. Further, the spatial distribution of the “parsimonious” parameters obtained from an autoregressive time-series analysis of the data reveals strong correlations with clearly identifiable flow phenomena around the perimeter, such as key points of the pressure distribution, flow separation, etc.The study, although limited to a single wind record, sixteen peripherally spaced pressure records, and only three minutes of selected time-history data, develops a coherent picture of a turbulent flow phenomenon at high Reynolds number. 相似文献