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991.
Recent theorizing in moral psychology extends rationalist models by calling attention to social and cultural influences (J. Haidt, 2001). Six studies using adolescents, university students, and adults measured the associations among the self-importance of moral identity, moral cognitions, and behavior. The psychometric properties of the measure were assessed through an examination of the underlying factor structure (Study 1) and convergent, nomological, and discriminant validity analyses (Studies 2 and 3). The predictive validity of the instrument was assessed by examinations of the relationships among the self-importance of moral identity, various psychological outcomes, and behavior (Studies 4, 5, and 6). The results are discussed in terms of models of moral behavior, social identity measurement, and the need to consider moral self-conceptions in explaining moral conduct. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
992.
A planar cable-direct-driven robot (CDDR) architecture is introduced with only translational freedoms. The motivation behind this work is to improve the serious cable interference problem with existing CDDRs and to avoid configurations where negative cable tensions are required to exert general forces on the environment and during dynamic motions. These problems generally arise for rotational CDDR motions. Thus, we propose a class of purely translational CDDRs; of course, these are not general but may only perform tasks where no rotational motion or resistance of moments is required at the end-effector. This article includes kinematics and statics modeling, determination of the statics workspace (the space wherein all possible Cartesian forces may be exerted with only positive cable tensions), plus a dynamics model and simulated control for planar translational CDDRs. Examples are presented to demonstrate simulated control including feedback linearization of the 4-cable CDDR (with two degrees of actuation redundancy) performing a Cartesian task. We introduce an on-line dynamic minimum torque estimation algorithm to ensure all cable tensions remain positive for all motion; otherwise slack cables result from the CDDR dynamics and control is lost. 相似文献
993.
Nahm Roh Joo Ho Young Kim Jin Taek Chung Sang II Choi 《Journal of Mechanical Science and Technology》2002,16(9):1112-1120
Numerical investigations on air staging and fuel staging were carried out with a newly designed coaxial cyclone combustor,
which uses the method of two stage coal combustion composed of pre-combustor and main combustor. The pre-combustor with a
high air/fuel ratio is designed to supply gas at high temperature to the main combustor. To avoid local high temperature region
in this process, secondary air is injected in the downstream. Together with the burned gas supplied from the pre-combustor
and the preheated air directly injected into main combustor, coals supplied through the main burner react rapidly at a low
air/fuel ratio. Strong swirling motion of cyclone combustor keeps the wall temperature high, which makes slagging combustion
possible. Alaska, US coal is used for calculations. Predictions were made for various coal flow rates in the main combustor
for fuel staging and for the various flow rate of secondary air in the pre-combustor for air staging. In-scattering angles
are also chosen as a variable to increase residence times of coal particles. Temperature fields and particle trajectories
for various conditions are described. Predicted temperature variations at the wall of the combustor are compared with corresponding
experimental data and show a similar trend. The in-scattering angle of 20° is recommended to increase the combustion efficiency
in the main chamber. 相似文献
994.
Ray Sterling John Carmody Walter H. Rockenstein II 《Tunnelling and Underground Space Technology incorporating Trenchless Technology Research》1992,7(2)
Life safety concerns related to fires and explosions are critical design issues for large subsurface facilities. This paper reviews these issues and discusses them in terms of existing life safety codes. The authors apply principles of layout and physical design for life safety to the development of large mined space facilities in the City of Minneapolis. Also discusses is a case study of life safety standards for a large underground building under consideration at the University of Minnesota. 相似文献
995.
Karli Lipinski Matthew J. McKay Fahmida Afrose Dr. Ashley N. Martfeld Prof. Roger E. Koeppe II Dr. Denise V. Greathouse 《Chembiochem : a European journal of chemical biology》2019,20(21):2784-2792
Membrane proteins are essential for many cell processes yet are more difficult to investigate than soluble proteins. Charged residues often contribute significantly to membrane protein function. Model peptides such as GWALP23 (acetyl-GGALW5LAL8LALALAL16ALW19LAGA-amide) can be used to characterize the influence of specific residues on transmembrane protein domains. We have substituted R8 and R16 in GWALP23 in place of L8 and L16, equidistant from the peptide center, and incorporated specific 2H-labeled alanine residues within the central sequence for detection by solid-state 2H NMR spectroscopy. The resulting pattern of [2H]Ala quadrupolar splitting (Δνq) magnitudes indicates the core helix for R8,16GWALP23 is significantly tilted to give a similar transmembrane orientation in thinner bilayers with either saturated C12:0 or C14:0 acyl chains (1,2-dilauroyl-sn-glycero-3-phosphocholine (DLPC) or 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC)) or unsaturated C16:1 Δ9 cis acyl chains. In bilayers of 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC; C18:1 Δ9 cis) multiple orientations are indicated, whereas in longer, unsaturated 1,2-dieicosenoyl-sn-glycero-3-phosphocholine (DEiPC; C20:1 Δ11 cis) bilayers, the R8,16GWALP23 helix adopts primarily a surface orientation. The inclusion of 10–20 mol % cholesterol in DOPC bilayers drives more of the R8,16GWALP23 helix population to the membrane surface, thereby allowing both charged arginines access to the interfacial lipid head groups. The results suggest that hydrophobic thickness and cholesterol content are more important than lipid saturation for the arginine peptide dynamics and helix orientation in lipid membranes. 相似文献
996.
Perfluorodecanoic acid (PFDA) is a peroxisome proliferator that causes a dose-dependent (20–80 mg/kg) increase in hepatic
triacylglycerol and cholesteryl ester levels in the rat. We hypothesized that PFDA may cause an increase in thede novo synthesis of fatty acids and cholesterol in this species, which would explain observed effects. The incorporation of3H2O into tissue lipids was examined 7 days after rats received vehicle or 20 or 80 mg/kg of PFDA. PFDA treatment decreased the
rate of synthesis of cholesterol and fatty acids in the liver and in epididymal fat pad. At a PFDA dose (20 mg/kg) that decreasedde novo synthesis of fatty acids and cholesterol, there was no effect on the concentration of fatty acids and cholesterol in the
liver, epididymal fat pads, and plasma. We conclude that PFDA induced fatty liver is due to either a decrease in the oxidation
of fatty acids in the liver, or an impairment of triacylglycerol catabolism and/or export from the liver, and is not the result
of an increase inde novo synthesis of fatty acids and cholesterol. 相似文献
997.
998.
Summary Effects of IPN (Interpenetrating Polymer Network) structures on the nonlinear optical properties of the polymers were studied. The IPN's were prepared using simultaneous polymerization, spin coating and post curing. The second order nonlinear optical properties of polymer films were evaluated by Maker-fringe experiment using the facilities in IBM research center at Almaden. The noncentrosymmetric structure for second order optical nonlinearity was obtained by applying an electric field using corona poling. The d33 values of epoxy,semi-IPN(50/50) and acrylic resin were 12.2 pm/V, 4.2 pm/V and 0.9 pm/V respectively. Semi-IPN had good stability after initial decay. 相似文献
999.
A multi-scale, dynamic, two-dimensional, heterogeneous model for catalytic steam methane reforming (SMR) is developed. The model, derived from first principles, accounts for diffusional limitations for both mass and energy within large industrial-scale catalyst particles. The diffusional limitations have been incorporated, not by the conventional method of computing the effectiveness factor, but by accounting for the transfer of species as a function of the concentration and temperature gradients existing between the gas phase and catalyst surface along the reactor length. The model has been validated with available industrial steady-state data from literature. The model was then used to study the dynamic behaviour of key variables and the effects of feed disturbances on catalyst core and tube wall temperatures. 相似文献
1000.
The authors studied the action of lithium ions on the responses of rat dorsal root ganglion neurons and frog spinal motoneurons evoked by monoamine agonists using the microelectrode technique. Lithium ions reversibly inhibit the depolarizing responses of spinal sensory neurons and motoneurons evoked by activation of muscarinic choline-, alpha 1-adreno-, and 5-hydroxytryptamine2 receptors, but enhance the hyperpolarizing neuronal responses evoked by activation of 5-hidroxytryptamine1A receptors. 相似文献