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371.
Fanuel A. Demas Ahmed Hassanali Esther N. Mwangi Edna C. Kunjeku Audrey R. Mabveni 《Journal of chemical ecology》2000,26(4):1079-1093
The response of mated naive Ixodiphagus hookeri females to cattle and Amblyomma variegatum nymphal odors was tested in a Y-tube olfactometer. I. hookeri females were attracted to cattle urine, dung, and odors from tick-free feeding sites of A. variegatum nymphs on cattle, e.g., dewlaps, front heels, and hind heels. Tick-free scrotal odors did not attract the parasitoids. Furthermore, odors from off-host unfed and fed A. variegatum nymphs did not attract the parasitoids, despite an increase in the number of the nymphs to amplify any odor signal. A blend of odors from feeding on-host nymphs and cattle scrota attracted the parasitoids. In T-tube bioassays, I. hookeri females were attracted to hexane washes and fecal extracts of A. variegatum nymphs. 相似文献
372.
Synthesis and characterization of poly(2,5‐didecyl‐1,4‐phenylene vinylene), poly(2,5‐didecyloxy‐1,4‐phenylene vinylene), and their alternating copolymer
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Crystal A. Young Sairoong Saowsupa Audrey Hammack Andrew A. Tangonan Piched Anuragudom Huiping Jia Andrew C. Jamison Sukon Panichphant Bruce E. Gnade T. Randall Lee 《应用聚合物科学杂志》2014,131(23)
The preparation of dialkyl‐substituted poly(2,5‐didecyl‐1,4‐phenylene vinylene) ( PDDPV ) by the Horner‐Emmons polycondensation is described. Its performance in an organic light‐emitting diode (OLED) device architecture is compared with devices prepared from the analogous dialkoxy‐substituted poly(2,5‐didecyloxy‐1,4‐phenylene vinylene) ( PDOPV ) and the corresponding alkyl‐alkoxy‐substituted alternating copolymer. Additionally, the structure, stability, electrochemical, and optical properties of the PPVs were characterized by gel permeation chromatography, thermogravimetric analysis, NMR spectroscopy, cyclic voltammetry, UV‐Visible spectroscopy, and fluorescence spectroscopy. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 41162. 相似文献
373.
Nitrate and nitrite concentrations were determined for sweet basil and scallions over 24 h to determine if time of sampling or harvest impacts concentrations in raw vegetables. Also, nitrate and nitrite concentrations were determined separately for various edible parts of these plants. Basil had significant changes in nitrate and nitrite concentrations over a 24 h period. Nitrate was correlated to changes in light intensity with a 3 h lag time. The highest nitrate concentrations in basil (2777 ppm) occurred around 3 h after the light intensity peaked and had low values (165–574 ppm) during the dark period. The scallion nitrate and nitrite concentrations were always low but nitrate showed a peak a few hours before sunrise. Nitrate and nitrite concentrations in some raw vegetables may be reduced by harvesting at the best time of day for each type of plant. Nitrate concentrations were different in the edible plant parts tested. 相似文献
374.
Howard A. Blair Jagan Chidella Fred Dushin Audrey Ferry Polar Humenn 《Annals of Mathematics and Artificial Intelligence》1997,21(2-4):153-186
We show how to regard covered logic programs as cellular automata. Covered logic programs are ones for which every variable
occurring in the body of a given clause also occurs in the head of the same clause. We generalize the class of register machine
programs to permit negative literals and characterize the members of this class of programs as n-state 2-dimensional cellular
automata. We show how monadic covered programs, the class of which is computationally universal, can be regarded as 1-dimensional
cellular automata. We show how to continuously (and differentiably) deform 1-dimensional cellular automata from one to another
and understand the arrangement of these cellular automata in a separable Hilbert space over the real numbers. The embedding
of the cellular automata of fixed radius r is a linear mapping into R2
2r+1 in which a cellular automaton's transition function is the attractor of a state-governed iterated function system of affine
contraction mappings. The class of covered monadic programs having a particular fixed point has a uniform arrangement in an
affine subspace of the Hilbert space l2. Furthermore, these programs are construable as almost everywhere continuous functions from the unit interval {x | 0 ≤ x
≤ 1} to the real numbers R. As one consequence, in particular, we can define a variety of natural metrics on the class of
these programs. Moreover, for each program in this class, the set of initial segments of the program's fixed points, with
respect to an ordering induced by the program's dependency relation, is a regular set.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
375.
Stewart Anita L.; Sherbourne Cathy D.; Wells Kenneth B.; Burnam M. Audrey; Rogers William H.; Hays Ron D.; Ware John E. Jr. 《Canadian Metallurgical Quarterly》1993,61(5):849
Differences in the functioning and well-being of adult patients with current or past depressive disorder who visited clinicians of different specialties in HMOs, solo practices, or large multispecialty group practices were examined. For patients in different systems, there were no significant differences in functioning and well-being across 12 domains tested. Patients of mental health specialists had worse mental health and more limitations in social activities, whereas patients of medical clinicians had worse physical functioning, more pain, more physical/psychophysiologic symptoms, and worse health perceptions. Thus, each system of care had depressed patients with a similar functioning and well-being "burden," but specialty sectors had patients with slightly different functioning and well-being profiles, probably reflecting patient selection of type of provider. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
376.
Carl-Hugo Pélisson Claudie Hubert Audrey Denicourt-Nowicki Alain Roucoux 《Topics in Catalysis》2013,56(13-14):1220-1227
Three mono- or tris-hydroxylated quaternary ammonium salts bearing various polar heads were synthesized and investigated as protective agents of rhodium(0) colloidal suspensions. The influence of the hydroxylated polar head on the micellar behaviour, size and morphology of the nanospecies was studied through surface tension measurements, dynamic light scattering and TEM experiments. Finally, the obtained surfactant-stabilized nanocatalysts were compared in the hydrogenation of benzene and its derivatives under very mild conditions (1 bar of H2, 20 °C) and in neat water. 相似文献
377.
Guillaume Schweicher Gabriele D'Avino Michael T. Ruggiero David J. Harkin Katharina Broch Deepak Venkateshvaran Guoming Liu Audrey Richard Christian Ruzi Jeff Armstrong Alan R. Kennedy Kenneth Shankland Kazuo Takimiya Yves H. Geerts J. Axel Zeitler Simone Fratini Henning Sirringhaus 《Advanced materials (Deerfield Beach, Fla.)》2019,31(43)
Molecular vibrations play a critical role in the charge transport properties of weakly van der Waals bonded organic semiconductors. To understand which specific phonon modes contribute most strongly to the electron–phonon coupling and ensuing thermal energetic disorder in some of the most widely studied high‐mobility molecular semiconductors, state‐of‐the‐art quantum mechanical simulations of the vibrational modes and the ensuing electron–phonon coupling constants are combined with experimental measurements of the low‐frequency vibrations using inelastic neutron scattering and terahertz time‐domain spectroscopy. In this way, the long‐axis sliding motion is identified as a “killer” phonon mode, which in some molecules contributes more than 80% to the total thermal disorder. Based on this insight, a way to rationalize mobility trends between different materials and derive important molecular design guidelines for new high‐mobility molecular semiconductors is suggested. 相似文献
378.
Christopher A. Browne Audrey Shih Sujit S. Datta 《Small (Weinheim an der Bergstrasse, Germany)》2020,16(9)
Polymer solutions are frequently used in enhanced oil recovery and groundwater remediation to improve the recovery of trapped nonaqueous fluids. However, applications are limited by an incomplete understanding of the flow in porous media. The tortuous pore structure imposes both shear and extension, which elongates polymers; moreover, the flow is often at large Weissenberg numbers, Wi, at which polymer elasticity in turn strongly alters the flow. This dynamic elongation can even produce flow instabilities with strong spatial and temporal fluctuations despite the low Reynolds number, Re. Unfortunately, macroscopic approaches are limited in their ability to characterize the pore‐scale flow. Thus, understanding how polymer conformations, flow dynamics, and pore geometry together determine these nontrivial flow patterns and impact macroscopic transport remains an outstanding challenge. This review describes how microfluidic tools can shed light on the physics underlying the flow of polymer solutions in porous media at high Wi and low Re. Specifically, microfluidic studies elucidate how steady and unsteady flow behavior depends on pore geometry and solution properties, and how polymer‐induced effects impact nonaqueous fluid recovery. This work thus provides new insights for polymer dynamics, non‐Newtonian fluid mechanics, and applications such as enhanced oil recovery and groundwater remediation. 相似文献
379.
Unpredictability and complexity of social interactions are important challenges for a low functioning autistic child. The
objective of this research is to study how a mobile robot can, by appearing more predictable, appealing and simple than a
human being, facilitate reciprocal interaction such as imitative play. By conducting an exploratory study involving four children,
we found that forms of shared conventions such as imitation of body movements and of familiar actions are higher with two
children paired with a human mediator, compared to two children paired with a robot mediator. However, the two children paired
with the robot mediator demonstrated increased shared attention (visual contact, physical proximity) and imitate facial expressions
(smile) more than the children paired with the human mediator.
相似文献
Henri MercierEmail: |
380.
Isabelle Favier Montserrat Gómez Guillermo Muller David Picurelli Audrey Nowicki Alain Roucoux Jordi Bou 《应用聚合物科学杂志》2007,105(5):2772-2782
Polymers I ‐ X with functionalized main chain were synthesized from commercial polymers containing reactive groups, anhydride (for Gantrez), or carboxylate (for polyacrylates) moieties, to be used as stabilizers of metallic nanoparticles. 1H HRMAS, 13C MAS NMR, IR, and GPC techniques were applied to characterize the new polymers. Metal transition nanoparticles stabilized with these polymers were prepared in organic solvents (Pd and Pt) and also in water/ethanol medium (Rh), under hydrogen atmosphere. TEM analysis revealed the formation of small nanoparticles, in the range ~ 3–20 nm, depending on the solvent, metal precursor, metal concentration, and polymer nature. Preliminary catalytic applications, C? C couplings using palladium and hydrogenations using platinum and rhodium systems in organic and also aqueous medium, were tested. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007 相似文献