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101.
David L. Brandon Thomas A. McKeon Stephanie A. Patfield Qiulian Kong Xiaohua He 《Journal of the American Oil Chemists' Society》2016,93(3):359-363
To facilitate the analysis of castor (Ricinus communis L.) seed fractions and germplasm for ricin content, we investigated the use of enzyme‐linked immunosorbent assay (ELISA) methods to differentiate between ricin toxin and the related Ricinus communis agglutinin (RCA). Both proteins are based on a heterodimeric AB structure, with a common A chain. RCA comprises two dimers of A and B chains. Both proteins are found in the meal remaining after castor oil extraction and impede the commercial production of castor seed in the USA. We identified pairs of monoclonal antibodies (mAbs) that could distinguish between the structurally related proteins that share a common A chain. Antibody specificity was determined by ELISA and checked by immunoblotting. We found that mAb–mAb pairs afforded quantification of each castor protein, and that a mAb paired with a commercial polyclonal antibody provided detection of both with comparable sensitivity. 相似文献
102.
Remendable polymers via reversible Diels–Alder cycloaddition of anthracene‐containing copolymers with fullerenes 下载免费PDF全文
Julia Kötteritzsch Robert Geitner Johannes Ahner Marcus Abend Stefan Zechel Jürgen Vitz Stephanie Hoeppener Benjamin Dietzek Michael Schmitt Jürgen Popp Ulrich S. Schubert Martin D. Hager 《应用聚合物科学杂志》2018,135(10)
Poly(lauryl methacrylate)s with anthracene moieties in the side chain were converted with C60‐fullerene and phenyl‐C61‐butyric acid methyl ester (PCBM), resulting in new remendable (self‐healing) polymeric materials. The utilization of differently substituted anthracene monomers enabled the tuning of the reactivity and the resulting mechanical properties. Copolymers with different contents of the anthracene moieties were synthesized and characterized using size exclusion chromatography, 1H nuclear magnetic resonance (NMR) spectroscopy as well as differential scanning calorimetry (DSC). 1H NMR spectroscopic studies were utilized in order to investigate the reversibility of the Diels–Alder reaction between copolymers with C60‐fullerene and PCBM, respectively, in solution. In order to investigate the conversion of the polymers with C60‐fullerene and PCBM in bulk, additionally, DSC, nanoindentation, rheology, atomic force microscopy (AFM), 3D microscopy, simultaneous thermal analysis (STA) and FT‐Raman investigations were performed. The fullerene‐containing copolymers could be healed in a temperature range of 40–80 °C. Consequently, a new generation of low temperature remendable polymers could be established. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 45916. 相似文献
103.
Cover Feature: Characterisation of the Carboxypeptidase G2 Catalytic Site and Design of New Inhibitors for Cancer Therapy (ChemBioChem 18/2018) 下载免费PDF全文
104.
Stimulus responsive surfactants based on dendritic glycerol azobenzene conjugates were used to solubilize and debundle single-walled carbon nanotubes in aqueous media. Their debundling property as well as their reaggregation behavior upon irradiation with light was examined and light triggered reversible bundling and precipitation are shown. 相似文献
105.
Venkataraman H Beer SB Bergen LA Essen Nv Geerke DP Vermeulen NP Commandeur JN 《Chembiochem : a European journal of chemical biology》2012,13(4):520-523
Inversion of stereoselectivity: screening of a minimal mutant library revealed a cytochrome P450?BM3 variant M01?A82W?S72I capable of producing 16?α-OH-testosterone. Remarkably, a single active site mutation S72I in M01?A82W inverted the stereoselectivity of hydroxylation from 16?β to 16?α. Introduction of S72I mutation in another 16?β-OH-selective variant M11?V87I, also resulted in similar inversion of stereoselectivity. 相似文献
106.
Amine Barkallah Johana Mörée Jose Sanchez Stephanie Druon Bocquet Jean Rivenc 《American Institute of Chemical Engineers》2009,55(2):294-311
Experimental and theoretical approaches based on a mathematical model, have been developed to study the evolution of environmental parameters (temperature, total pressure, relative humidity, and water vapor partial pressure) inside a housing of an electronic device with a window containing a macroporous membrane. The model was based on the coupling of mass and heat transfer taking into account the effects of polarization of concentration in boundary layers. Membranes have been characterized by mercury porosimetry, liquid entry pressure measurements, scanning electron microscopy, and gas permeation. Once the model was experimentally validated, it was applied to investigate the influence of membranes on heat and mass transfer and to study the impact of the boundary layers on the global mass transport. The results demonstrated the importance of the membrane choice and dimensions to get the best temperature regulation and avoid water condensation inside an automotive electronic control unit (ECU). © 2008 American Institute of Chemical Engineers AIChE J, 2009 相似文献
107.
Christian Müller Dr. Maria Antonia Gomez‐Zurita Frau Dr. Dario Ballinari Dr. Sonia Colombo Dr. Alessandro Bitto Dr. Enzo Martegani Prof. Cristina Airoldi Dr. Anske Stephanie van Neuren Dr. Matthias Stein Dr. Jörg Weiser Dr. Carlo Battistini Dr. Francesco Peri Prof. 《ChemMedChem》2009,4(4):524-528
A panel of new potential Ras ligands was generated by decorating a tricyclic levoglucosenone‐derived scaffold with aromatic moieties. Some members of the panel show in vitro inhibitory activity toward the nucleotide exchange process on Ras and are toxic to some human cancer cell lines.
108.
In biological systems, it is expected that gene expression levels generally will correlate with temporally varying physiological and biological needs, and that gene expression levels could regulate biological capabilities. In moth species, male response to female sex pheromones often is affected by moth age and mating status. Odorant receptors (ORs) expressed in neurons within male antennae are critical for detecting the female pheromones. Therefore, we hypothesized that the expression level of these receptor proteins would be affected by age and mating status of male moths. We examined expression levels of two OR genes that are preferentially expressed in the male antennae of Heliothis virescens (HvOR13 and HvOR15) and Heliothis subflexa (HsOR13 and HsOR15). Antennae were dissected from virgin males at 2 h, 1 d, 2 d, 4 d, and 8 d. We also dissected antennae from 4-d-old mated males. We found that age had no effect on expression levels of either OR in either species, except for a small difference in HsOR15 expression between 2 h and 8-d-old virgin males. Furthermore, we found no effect of mating status on expression level of these ORs in either species. We discuss these findings in relationship to studies of age and mating status effects on male electrophysiological and behavioral response to female pheromones, and contrast our results to studies on the effects of age and mating status on gene expression of pheromone receptor proteins and pheromone binding proteins in other moths. 相似文献
109.
Ramón Morales Chabrand Hyun-Jung Kim Cheng Zhang Charles E. Glatz Stephanie Jung 《Journal of the American Oil Chemists' Society》2008,85(4):383-390
Characterization and destabilization of the emulsion formed during aqueous extraction of oil from soybean flour were investigated.
This emulsion was collected as a cream layer and was subjected to various single and combined treatments, including thermal
treatments and enzymatic treatments, aimed at recovery of free oil. The soybean oil emulsion formed during the aqueous extraction
processing of full fat flour contains high molecular weight glycinin and β-conglycinin proteins and smaller oleosin proteins,
which form a multilayer interface. Heat treatment alone did not modify the free oil recovery but freeze–thaw treatment increased
the oil yield from 3 to 22%. After enzymatic treatment of the emulsion, its mean droplet size changed from 5 to 14 μm and
the oil recovery increased to 23%. This increase could be attributed to the removal (due to enzymatic hydrolysis) of large
molecular weight polypeptides from the emulsion interface, resulting in partial emulsion destabilization. When enzymatic treatment
was followed by a freeze–thaw step, the oil recovery increased to 46%. This result can be attributed to the thinner interfacial
membrane after enzymatic hydrolysis, partial coalescence during freeze–thaw, and coalescence during centrifugation. Despite
the reduction in emulsion stability achieved, additional demulsification approaches need to be pursued to obtain an acceptably
high conversion to free oil. 相似文献
110.
<正>关于双组分纤维纺丝技术的第一批专利发表于20世纪40年代早期。从20世纪60年代中期开始,聚合物业界倾向于采用聚合物共混和混合物以改进材料的性能。双组分纤维由两种聚合物成分组成,它们彼此并列或互相缠绕。双组分纤维纺丝可 相似文献