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991.
R. G. Bistline Jr. W. R. Noble J. K. Weil W. M. Linfield 《Journal of the American Oil Chemists' Society》1972,49(1):63-69
Blends of soap with small amounts of lime soap dispersing agents are efficient detergents in hard water and require little
or no tripolyphosphate builder. Lime soap dispersing agents examined include sulfated ethoxylated fatty alcohols, sulfated
N-(2-hydroxyethyl) fatty amides, methyl esters of α-sulfo fatty acids, 2-sulfoethyl fatty acid esters and N-methyl-N-(2-sulfoethyl)
fatty amides as well as nonionics derived from tallow alcohols. Detergency evaluations were carried out with three commercial
soiled cotton cloths as well as by a laboratory multi-wash technique. Formulations containing 80% soap, 10% lime soap dispersing
agent and 10% builder gave optimum detergency values. Builder effectiveness was rated tripolyphosphate>silicate (1:1.6)> metasilicate
= citrate = oxydiacetate = nitrilotriacetate>carbonate≫sulfate. The detergency of soap-lime soap dispersed combinations compared
favorably with a standard brand household heavy duty granular detergent in 50, 150 and 300 ppm hardness water on three soiled
cloths.
Presented at the AOCS Meeting, Atlantic City, October 1971.
East. Market. Nutr. Res. Div., ARS, USDA. 相似文献
992.
R. G. Bistline Jr. W. R. Noble W. M. Linfield 《Journal of the American Oil Chemists' Society》1976,53(2):64-68
Surface active amphoteric derivatives were prepared from alkylbenzenesulfonyl chlorides. Industrial detergent alkylates, as
well as benzene and pure 1-phenylalkanes whose side chains ranged from C1 to C12, were used as starting materials in this study of chemical structure-physical property relationships. The alkylbenzenes were
first converted into the corresponding alkylbenzenesulfonyl chlorides with chlorosulfonic acid, and the sulfonyl chlorides
were further treated with N,N-dimethyl-1,3-diaminopropane or N,N-bis-(2-hydroxyethyl)-1,3-diaminopropane. The reaction products
were quaternized with propanesultone to produce amphoteric surfactants in high yields. The N,N-dimethyl herivatives of pure
phenylalkanes were white crystalline powders, whereas the N,N-bis-(2-hydroxyethyl) derivatives were light , lime soap dispersing
requirement, surface tension, wetting ability, and calcium ion stability were determined. The commercial detergent alkylate
derivatives showed good detergency by themselves as well as in formulations with soap or with soap and silicate builder. Good
lime soap dispersing properties were observed with compounds possessing a side chain of at least 4 carbon atoms.
Presented at the AOCS Fall Meeting, Philadelphia, September 1974. 相似文献
993.
This study aimed to investigate whether different personality variables were associated with shift work tolerance, and whether these potential associations were moderated by various types of shift work. The sample comprised 1505 nurses who worked either two or three rotating shifts. Personality traits were measured in terms of morningness, flexibility, languidity and hardiness. Morningness reflects the tendency to be alert relatively early in the morning and sleepy relatively early in the evening. Flexibility denotes the ability to both work and sleep at odd times of the day, while languidity concerns the tendency to become tired/sleepy when cutting down on sleep. Hardiness relates to resilience to stressful life events. The dependent variables in this study comprised of measures of insomnia, sleepiness, depression and anxiety. Hierarchical regression analyses, which controlled for demographic variables and work load, revealed that Morningness was significantly and negatively related to insomnia. The Morningness by Shift type interaction was overall significant for depressive symptoms. Morningness was near significantly associated with lower levels of depressive symptoms in three-shift workers, but unrelated to depressive symptoms in two-shift workers. Flexibility was associated with higher levels of depressive symptoms. Flexibility by Shift type interaction was significant for insomnia, indicating that flexibility was negatively associated with insomnia for three-shift workers and unrelated with insomnia for two-shift workers. Languidity was associated with higher levels of sleepiness, depressive and anxiety symptoms. Hardiness was associated with lower levels of all four dependent variables. 相似文献
994.
Joachim Müller Sven Simon Uwe Motschmann Josef Schüle Karl-Heinz Glassmeier Gavin J. Pringle 《Computer Physics Communications》2011,182(4):946-966
The interaction between magnetized space plasmas and obstacles like comets, asteroids or planets is determined by a variety of physical processes that occur simultaneously on significantly different length and time scales. Frequently the dynamics of individual ions play a key role for the shape of the interaction region: strong velocity shear between light and heavy plasma constituents, non-Maxwellian particle distributions due to pick up and asymmetries in the magnetic field topology are crucial in determining this type of interaction. Covering these processes is beyond the scope of any Magnetohydrodynamic (MHD) model. In order to account for these effects we have developed a new adaptive hybrid code A.I.K.E.F. (Adaptive Ion-Kinetic Electron-Fluid). The code operates on Cartesian meshes that can adapt to the physical structures in both, space and time. To the authors' knowledge, there is no other adaptive hybrid simulation code in space plasma physics to the present day. Adaptivity is implemented by means of Hybrid-Block-AMR, that is individual octs are refined rather than entire blocks, where an oct is one eighth of a block. In order to account for a reasonable number of particles in each cell, particles are refined via splitting and merging. Both procedures conserve mass, momentum and kinetic energy. The code is implemented in C++ and efficiently parallelized for distributed systems by means of the Message Passing Interface (MPI). In order to demonstrate the validity of our newly developed code we have applied it to a series of fundamental test scenarios. On the one hand we demonstrate that the dispersion relation as well as the propagation characteristics of MHD and whistler mode waves are quantitatively reproduced by our simulation code. Wave propagation remains unaffected when traveling through regions that include different refinement levels. On the other hand we verify that the results obtained on high resolution uniform meshes are identical to the results from adaptive simulations that use coarse base meshes but include various levels of refinement. A remarkable speedup could be observed: the adaptive simulations required 71 times less CPU-hours than the uniform mesh simulations. Finally, we present a first series of global, three-dimensional simulations for the interaction of Mercury with the solar wind and a real time study of Titan's plasma interaction during a magnetosheath excursion. 相似文献
995.
Guerric le Maire Claire Marsden Flávio Jorge Ponzoni Agnès Bégué Yann Nouvellon 《Remote sensing of environment》2011,115(2):586-2625
The leaf area index (LAI) of fast-growing Eucalyptus plantations is highly dynamic both seasonally and inter-annually, and is spatially variable depending on pedo-climatic conditions. LAI is very important in determining the carbon and water balance of a stand, but is difficult to measure during a complete stand rotation and at large scales. Remote-sensing methods allowing the retrieval of LAI time series with accuracy and precision are therefore necessary. Here, we tested two methods for LAI estimation from MODIS 250m resolution red and near-infrared (NIR) reflectance time series. The first method involved the inversion of a coupled model of leaf reflectance and transmittance (PROSPECT4), soil reflectance (SOILSPECT) and canopy radiative transfer (4SAIL2). Model parameters other than the LAI were either fixed to measured constant values, or allowed to vary seasonally and/or with stand age according to trends observed in field measurements. The LAI was assumed to vary throughout the rotation following a series of alternately increasing and decreasing sigmoid curves. The parameters of each sigmoid curve that allowed the best fit of simulated canopy reflectance to MODIS red and NIR reflectance data were obtained by minimization techniques. The second method was based on a linear relationship between the LAI and values of the GEneralized Soil Adjusted Vegetation Index (GESAVI), which was calibrated using destructive LAI measurements made at two seasons, on Eucalyptus stands of different ages and productivity levels. The ability of each approach to reproduce field-measured LAI values was assessed, and uncertainty on results and parameter sensitivities were examined. Both methods offered a good fit between measured and estimated LAI (R2 = 0.80 and R2 = 0.62 for model inversion and GESAVI-based methods, respectively), but the GESAVI-based method overestimated the LAI at young ages. 相似文献
996.
Concerned with multi-objective reinforcement learning (MORL), this paper presents MOMCTS, an extension of Monte-Carlo Tree Search to multi-objective sequential decision making, embedding two decision rules respectively based on the hypervolume indicator and the Pareto dominance reward. The MOMCTS approaches are firstly compared with the MORL state of the art on two artificial problems, the two-objective Deep Sea Treasure problem and the three-objective Resource Gathering problem. The scalability of MOMCTS is also examined in the context of the NP-hard grid scheduling problem, showing that the MOMCTS performance matches the (non-RL based) state of the art albeit with a higher computational cost. 相似文献
997.
Danièle Fournier-prunaret 《电信纪事》1987,42(5-6):247-254
One studies the bifurcations structure of the endo-morphism of the circle into itself T defined by : \(Tx_n = x_n + \Omega - \frac{K}{{2\pi }}\sin (2\pi x_n )\) (mod. 1) in a part of the parameter plane (K, Ω). One makes appear a mixing between two bifurcations structure : the boxes in files one which appears in dijfeomorphisms of the circle and the box within a box one which appears in one-dimensional endomorphism defined by a polynomial of second or third degree. 相似文献
998.
We investigate the stresses in thin films with sub-millimeter lateral spatial resolution using a dense array of prefabricated cantilever beams prepared by microelectromechanical-system techniques. Stress induced deflection of the cantilever is interrogated by an optical (laser/position sensitive detector) measurement system. Composition spread films are deposited on the cantilever array using a three gun on-axis magnetron cosputtering system. The position dependent composition is inferred using rate calibrations and verified by electron microprobe/energy dispersive spectroscopy. We demonstrate the function of this system using an Fe-Ni-Al composition spread with approximately 1 at. % resolution. This approach allows for measurement of the composition dependence of other electromechanical properties such as the martensitic phase transition temperature of traditional and ferromagnetic shape-memory alloys, as well as the properties of hydrogen storage materials and the magnetic response of magnetostrictive materials. 相似文献
999.
变速器动力学建模的键合图法 总被引:1,自引:0,他引:1
介绍了键合图的基本原理和特点,建立了Audil00变速器的键合图模型,并且推导了该系统的状态方程,说明键合图适用于车辆动力传动系统的部件动力学建模及分析。 相似文献
1000.
Biological objects may be arrested in defined stages of their activity by fast freezing and may then be structurally examined. If the time between the start of activity and freezing is controlled, structural rearrangements due to biological function can be determined. Cryo-electron microscopy shows great potential for the study of such time-dependent phenomena. This study examines the actin polymerization process using cryo-electron microscopy of vitrified specimens. Actin filaments are shown to undergo a structural change during polymerization. In the early stages of the polymerization process (t < 2 min), filaments exhibit a pronounced structural variation and frequently show a central low-density area. In the later stages of the polymerization, F-actin-ADP filaments have a more uniform appearance and rarely display a central low-density area. These findings, analysed on the basis of a previously proposed polymerization model, suggest that polymerization intermediates (F-actin-ATP and more probably F-actin-ADP-Pi) and filaments at steady state (F-actin-ADP) have different structures. To investigate the physiological relevance of these results at the cellular level, the potential of cryo-substitution in preserving the structure of muscular fibre was assessed. Optical diffraction patterns of relaxed and contracted frog cutaneous muscle are similar to the corresponding X-ray diffraction patterns. The resolution of the images extends to about 7 nm. These results show that dynamic study of muscle contraction is possible using cryo-substitution. 相似文献