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81.
本文总结了电厂性能计算所面临的实用化问题,在分析的基础上提出相应的解决方案。 相似文献
82.
将常规的数字温度仪与压力计通过串行口和计算机连接,构建基于LabVIEW 8.0测定纯液体蒸发焓的虚拟仪器,实现实验数据的动态采集、实时显示、自动绘制p~T曲线并显示曲线方程、自动数据处理和写成结果报告等。应用结果表明:基于LabVIEW构建的测定纯液体蒸发焓的虚拟仪器,免除人工操作的繁琐和人为误差,测定乙醇和苯蒸发焓的相对误差分别为0.86%、-2.97%,提高了测量结果的准确度,且具有界面友好,操作简便和功能易扩展等诸多优点。 相似文献
83.
A biped walking robot should be able to keep balance even in the presence of disturbing forces.This paper presents a step strategy concept of biped walking robot that is stabilized by using reaction null space method.The called "step strategy" can be modeled by means of the reaction null space method that introduced earlier to tackle dynamic interaction problems of free-floating robots,or moving base robots in general.6-DOF biped robot model simulations are used to confirm the validity. 相似文献
84.
Huimin Yu Deyu Wang Huanyu Jin Pan Wu Xuan Wu Dewei Chu Yi Lu Xiaofei Yang Haolan Xu 《Advanced functional materials》2023,33(24):2214828
Improving interfacial solar evaporation performance is crucial for the practical application of this technology in solar-driven seawater desalination. Lowering evaporation enthalpy is one of the most promising and effective strategies to significantly improve solar evaporation rate. In this study, a new pathway to lower vaporization enthalpy by introducing heterogeneous interactions between hydrophilic hybrid materials and water molecules is developed. 2D MoN1.2 nanosheets are synthesized and integrated with rGO nanosheets to form stacked MoN1.2-rGO heterostructures with massive junction interfaces for interfacial solar evaporation. Molecular dynamics simulation confirms that atomic thick 2D MoN1.2 and rGO in the MoN1.2-rGO heterostructures simultaneously interact with water molecules, while the interactions are remarkably different. These heterogeneous interactions cause an imbalanced water state, which easily breaks the hydrogen bonds between water molecules, leading to dramatically lowered vaporization enthalpy and improved solar evaporation rate (2.6 kg m−2 h−1). This study provides a promising strategy for designing 2D-2D heterostructures to regulate evaporation enthalpy to improve solar evaporate rate for clean water production. 相似文献
85.
《Calphad》2023
RuO4 oxide appears much less stable than RuO2(s) in the Ru–O binary system with a melting point close to room temperature and a certain propensity to vaporize or decompose at low temperatures. Ab initio simulations in the framework of density functional theory (DFT) on RuO4(s) are performed to analyze the cubic and monoclinic structures and to evaluate the heat capacities at low temperatures. Then, a critical evaluation of thermodynamic data from calorimetry and vapor pressure determinations - was carried out coupled with ab-initio calculations to propose new thermodynamic data: the entropy.S° (RuO4, s, cubic, 298K) = 132.7 J·K−1mol−1 and formation enthalpy.ΔfH° (RuO4, s, cubic, 298K) = −252.4 ± 5.5 kJ mol−1. 相似文献
86.
《材料科学技术学报》2019,35(10):2163-2168
CBN/Cu-Sn-Ti (CBN: cubic boron nitride) composites are prepared by active brazing sintering at 1123 K, 1173 K, 1223 K and 1273 K, respectively. The effects of brazing temperature on the wettability, interfacial characteristics, and elemental distribution variations are fully investigated. When the brazing temperature is below 1223 K, completely uncoated and/or partially coated CBN particles with sharp edges can still be observed, and the reaction layer, mainly composed of TiN and TiB2, appears to be thin and uneven. When the brazing temperature is 1223 K, all CBN particles are completely coated, suggesting that adequate wetting has taken place. Besides, as Ti diffuses thoroughly and enriches the interface, the reaction layer, filled primarily by TiN, TiB2 and TiB, becomes thicker (about 1.30 μm), more uniform, stable and continuous. Further increasing the temperature to 1273 K is unnecessary or even harmful as the reaction layer thickness undergoes negligible change yet some tiny micro-cracks appear on the interface, which may likely deteriorate the grinding capability of the final brazing products. 相似文献
87.
88.
Murat Arcak Author vitae 《Automatica》2011,(6):1219-1229
We present a condition that guarantees spatial uniformity for the asymptotic behavior of the solutions of a reaction–diffusion PDE with Neumann boundary conditions. This condition makes use of the Jacobian matrix of the reaction terms and the second Neumann eigenvalue of the Laplacian operator on the given spatial domain, and eliminates the global Lipschitz assumptions commonly used in mathematical biology literature. We then derive numerical procedures that employ linear matrix inequalities to certify this condition, and illustrate these procedures on models of several biochemical reaction networks. Finally, we present an analog of this PDE result for the synchronization of a network of identical ODE models coupled by diffusion terms. From a systems biology perspective, the main contribution of the paper is to blend analytical and numerical tools from nonlinear systems and control theory to derive a relaxed and verifiable condition for spatial uniformity of biological processes. 相似文献
89.
化学混沌与BZ反应的细观元胞自动机模拟 总被引:3,自引:3,他引:0
将所提出的细观元胞自动要应用于化学混沌与BZ反应的计算机模拟,分别制定了8组分和5组分系统中粒子随机运动和反应碰撞的演化规则,建立了Willamowski-Rossler化学混沌与Belousov-Zhalbotinski反应的二维元胞自动机模型,并在计算机上对它们进行了成功地动态模拟。 相似文献
90.
Beth V. Holbrook Thomas R. HrabikDonn K. Branstrator Allen F. Mensinger 《Journal of Great Lakes research》2013
Reaction distances under various light intensities (0-19 uE/m2/s), angles of attack, swimming speeds, and percentage of overall foraging success were measured. Extensive efforts have been invested in restoring lean lake trout (Salvelinus namaycush) populations in the Laurentian Great Lakes, but successful natural recruitment of lake trout continues to be rare outside of Lake Superior and parts of Lake Huron. There is evidence of high mortality during the first several months after eggs hatch in the spring, but little is known about the foraging mechanisms of this age-0 life stage. We developed a foraging model for age-0 lake trout (S. namaycush) in response to amphipods (Hyalella azteca) and mysids (Mysis diluviana) by simulating underwater environmental conditions in the Great Lakes using a temperature-controlled chamber and spectrally matched lighting. Reaction distances under various light intensities (0–19 uE/m2/s), angles of attack, swimming speeds, and percentage of overall foraging success were measured. Intake rates under different light intensities and prey densities were also measured. Age-0 lake trout were non-responsive in the dark, but were equally responsive under all light levels tested. Age-0 lake trout also demonstrated a longer reaction distance in response to moving prey, particularly mysids, which had an escape response that reduced overall foraging success. We determined that prey intake rate (numeric or biomass) could be modeled most accurately as a function of prey density using a Michaelis–Menton equation and that even under low mysid densities (3 individuals/m2), age-0 lake trout could quickly satisfy their energetic demands in a benthic setting. 相似文献