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991.
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Huber Daniel M.; Sauer Eric M.; Mrdjenovich Adam J.; Gugiu P. Cristian 《Canadian Metallurgical Quarterly》2010,4(4):244
Authors of the current study examined the contributions of four factors on the advisory working alliance from counseling psychology advisees' perspectives: (a) anxious attachment orientation, (b) avoidant attachment orientation, (c) frequency of advising meetings, and (d) method of pairing an advisee to a faculty advisor. Participants were 109 counseling psychology doctoral students who were enrolled in American Psychological Association-accredited programs. A mixed model analysis indicated that lower attachment-anxiety scores, lower attachment-avoidance scores, and advisees choosing advisors each contributed to higher advisory working alliance scores. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
993.
Jie Song Adam M. Baker Christopher W. Macosko Randy H. Ewoldt 《American Institute of Chemical Engineers》2013,59(9):3391-3402
It is demonstrated that processing flow affects the kinetics of the interfacial coupling reaction between functional groups that are grafted to polymer chains. At melt temperatures the amine group on the end of nylon 6 chains reacts with maleic anhydride grafted polyethylene (PE‐MA) and forms graft copolymers. Bilayers were made by lamination and coextrusion and adhesion was measured using asymmetric dual cantilever beam (ADCB). The amount of graft copolymer in the interface was quantified by X‐ray photon spectroscopy (XPS). With quiescent lamination, adhesion increased with temperature and the concentration of PE‐MA. The adhesion metric, Gc (critical energy release rate), plotted as a function of Σ (interfacial copolymer density) fell on the same master curve, unifying reaction process, temperature and time. Gc was a linear function of Σ for low‐copolymer coverage and weak adhesion. For relatively high coverage and strong adhesion, Gc scaled with Σ. 2 Coextrusion with compressive flow resulted in a reaction rate strikingly two‐orders of magnitude faster than that without compressive flow. The rate in the noncompressive die was close to quiescent lamination. Even for lamination, when compressive flow was applied normal to the interface, the coupling reaction rate was also greatly accelerated. Several mechanisms are speculated for this remarkable acceleration in polymer chain coupling. © 2013 American Institute of Chemical Engineers AIChE J, 59: 3391–3402, 2013 相似文献
994.
Magdalena Jasińska Jerzy Bałdyga Michael Cooke Adam Kowalski 《Chemical Engineering Research and Design》2013
A new method based on experimental determination of the product distribution of a set of complex test reactions has been introduced and applied to study mass transfer in liquid–liquid systems. The test reactions consist of two parallel reactions, one of them being instantaneous and the second fast relative to mass transfer. Two reactants are transferred from the dispersed, organic phase (phase volume 1% vol) to the continuous aqueous phase, where the third reactant is present. Experiments were carried out in a batch system agitated with either a six-blade paddle impeller or a high-shear rotor–stator LR4 Silverson mixer to disperse drops and increase the mass transfer rate. The product distribution and the drop size distribution were measured using gas chromatography–mass spectroscopy and Malvern MasterSizer, respectively with pH variation recorded during the process. The results show that the focused supply of energy in the Silverson mixer is effective for the short term irreversible drop break-up process producing smaller droplets than the six-blade paddle impeller. However for the long term mass transfer process the paddle impeller is more effective due to more uniform supply of energy and better mixing throughout the tank compared to the more localized mixing of the Silverson. 相似文献
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The insignificant relationship between rewards and actual compliance with information security policies does not make sense. Quite possibly this relationship results from not applying rewards for security compliance. 相似文献
999.
Roksana Markiewicz Adam Klimaszyk Marcin Jarek Micha Taube Patryk Florczak Marek Kempka Zbigniew Fojud Stefan Jurga 《International journal of molecular sciences》2021,22(11)
The application of ionic liquids (ILs) has grown enormously, from their use as simple solvents, catalysts, media in separation science, or electrolytes to that as task-specific, tunable molecular machines with appropriate properties. A thorough understanding of these properties and structure–property relationships is needed to fully exploit their potential, open new directions in IL-based research and, finally, properly implement the appropriate applications. In this work, we investigated the structure–properties relationships of a series of alkyltriethylammonium bis(trifluoromethanesulfonyl)imide [TEA-R][TFSI] ionic liquids in relation to their thermal behavior, structure organization, and self-diffusion coefficients in the bulk state using DSC, FT-IR, SAXS, and NMR diffusometry techniques. The phase transition temperatures were determined, indicating alkyl chain dependency. Fourier-transformed infrared spectroscopy studies revealed the structuration of the ionic liquids along with alkyl chain elongation. SAXS experiments clearly demonstrated the existence of polar/non-polar domains. The alkyl chain length influenced the expansion of the non-polar domains, leading to the expansion between cation heads in polar regions of the structured IL. 1H NMR self-diffusion coefficients indicated that alkyl chain elongation generally caused the lowering of the self-diffusion coefficients. Moreover, we show that the diffusion of anions and cations of ILs is similar, even though they vary in their size. 相似文献
1000.
Jaromir Gumulec Michaela Fojtu Martina Raudenska Marketa Sztalmachova Anna Skotakova Jana Vlachova Sylvie Skalickova Lukas Nejdl Pavel Kopel Lucia Knopfova Vojtech Adam Rene Kizek Marie Stiborova Petr Babula Michal Masarik 《International journal of molecular sciences》2014,15(12):22960-22977
Doxorubicin is an effective chemotherapeutic drug, however, its toxicity is a significant limitation in therapy. Encapsulation of doxorubicin inside liposomes or ferritin cages decreases cardiotoxicity while maintaining anticancer potency. We synthesized novel apoferritin- and liposome-encapsulated forms of doxorubicin (“Apodox” and “lip-8-dox”) and compared its toxicity with doxorubicin and Myocet on prostate cell lines. Three different prostatic cell lines PNT1A, 22Rv1, and LNCaP were chosen. The toxicity of the modified doxorubicin forms was compared to conventional doxorubicin using the MTT assay, real-time cell impedance-based cell growth method (RTCA), and flow cytometry. The efficiency of doxorubicin entrapment was 56% in apoferritin cages and 42% in the liposome carrier. The accuracy of the RTCA system was verified by flow-cytometric analysis of cell viability. The doxorubicin half maximal inhibition concentrations (IC50) were determined as 170.5, 234.0, and 169.0 nM for PNT1A, 22Rv1, and LNCaP, respectively by RTCA. Lip8-dox is less toxic on the non-tumor cell line PNT1A compared to doxorubicin, while still maintaining the toxicity to tumorous cell lines similar to doxorubicin or epirubicin (IC50 = 2076.7 nM for PNT1A vs. 935.3 and 729.0 nM for 22Rv1 and LNCaP). Apodox IC50 was determined as follows: 603.1, 1344.2, and 931.2 nM for PNT1A, 22Rv1, and LNCaP. 相似文献