查询词典 chemical energy

DESIGN: A 2-y longitudinal study to examine whether components of energy metabolism are predictors of body fat gain was conducted in 114 preadolescent African American and white children aged 9-11 y by measuring total daily energy expenditure on the basis of doubly labeled water, resting metabolic rate, the thermic effect of food, energy expended in physical activity, and substrate oxidation after a meal.

设计：研究对象为114个青春期前的非裔美国小孩和白人小孩，年龄为9-11岁。通过用双标水法测定每日热能消耗总量、测定静息代谢率、食物的产热效应、体力活动能量消耗及餐后的底物氧化，进行一个2年的纵向调查，检测能量代谢的组成是否能够预测体内脂肪增加。

The energy of the excited wave is almost proportional to the energy of the primary wave, and increases slowly with initial energy of the secondary wave growing up, too.

生成波的能量几乎正比于主波的能量，也随次波的能量增大而增大。

In this topic, the dynamic analysis methods for piezoelectric vibrator are studied systematically based on the theoretical model, FEM numerical experimentation and FEM governing equation for given compound-mode vibrator, and some valuable conclusions are obtained. The main work accomplished is summarized as follows: 1.Elaborate the main modeling methods for piezoelectric vibrator and the significance and necessity to study the dynamic characteristics of piezoelectric vibrator which emphasize the urgency of this paper. 2.Take the bending deformation induced by piezoelectric ceramic as example, the energy transfer mechanism of electric energy to mechanical energy are analyzed; the motion and force transfer mechanism are analyzed for the longitudinal-bending vibrator. 3.Based on mode assumption and Hamilton principle, the coupling model of piezoelectric vibrator of linear USM is built; moreover, the equivalent circuit model is obtained and a coupling equation represents the relation between electric parameters and mechanical parameters is derived which provides foundation to match the vibrator and driving circuit. 4.Combine the constitutive equation of piezoelectric ceramic with elastic-dynamical equation, geometric equation in force field and the Maxwell equation in electric field and the corresponding boundary condition equation, the FEM control equation for piezoelectric vibrator of USM to solve dynamic electro-mechanical coupling field is established by employing the principle of virtual displacement. The equation lays the foundation to study the non-linear constitutive equation of piezoelectric ceramic driven by high-power. 5.Define the dynamic indexes of characteristic of vibrator and carry out variable parameters simulation by calculating the model parameters and the electric characteristics of vibrator are simulated according to the equivalent circuit model. By numerical experimentation, the working mode of vibration of vibrator and the shock excitation results of the working frequency band which provides the mode frequency to realize bimodal are analyzed. Detailed calculation of the electro-mechanical coupling field parameters is made by programming the FEM control equation.

本课题从理论模型、有限元数值试验、有限元控制模型等方面以复合振动模式振子为例对超声电机压电振子的动力学特性及其分析方法进行了全面系统地研究，得出了许多有价值的结论，主要概括如下： 1、阐述了目前针对超声电机压电振子的主要建模方法，对压电振子动态特性的研究意义和必要性进行了论述，突出了本文研究内容的迫切性； 2、以压电陶瓷诱发弹性体发生弯曲变形为例，分析了压电陶瓷通过诱发应变来实现机电能量转换的机理；对基于纵弯模式的压电振子的运动及动力传递机理进行了分析； 3、基于模态假定，利用分析动力学的Hamilton原理，建立了面向直线超声电机压电振子的机电耦合动力学模型，并据此建立了压电振子的等效电路模型，导出了电参量与动力学特性参量的耦合方程，为压电振子与驱动电路的匹配提供了依据； 4、从压电陶瓷的本构方程出发，综合力场的弹性动力学方程、几何方程、电场的麦克斯韦方程以及相应的边界条件方程，采用虚位移原理，建立了压电振子动态问题机电耦合场求解的有限元控制方程，为研究其大功率驱动下的非线性本构模型奠定了基础； 5、界定压电振子的动力学特性指标，对压电振子的机电耦合动力学模型参数进行计算及变参数仿真；依据等效电路模型，对压电振子的电学特性进行了仿真分析；通过有限元数值实验，对压电振子工作模态附近的模态振型及工作频率附近的频段进行了激振效果分析，找出了实现模态简并的激振频率；利用有限元控制方程，通过编程计算，对压电振子的力电耦合场参数进行了详细计算，得出了一些有价值的结论。

It is found that energy density of static sphere symmetry of gravitational field is negative in the sphere coordinates and their energy density is positive definite in the Cartesian coordinates. This result shows that Einstien-Tolman expression of the energy-momentum pseudo tensor in the Cartesian coordinates have reasonable property.

在球坐标系和直角坐标系下我们用Einstien-Tolman表述计算球对称静态引力场的能量密度，发现在球坐标系下能量密度为负，而在直角坐标系下能量密度为正；这样的结果显示了Einstien-Tolman表述在直角坐标系下有其合理性。

If harnessed, latent energy in biomass, wind and solar energy sources could quintuple energy available to Third World villages.

如果可以的话，生物质能，风能，太阳能中存在的潜在能量能够提供给第三世界5倍的能源。

The triangular shape distributions would cause two-peaked energy distribution near the threshold energy, which must affect the group transfer matrix. The rectangular shape make the too large, that may lead to a negative neutron KERMA (kinetic energy release in materials) factor.

这些简单的近似描述，将导致产生散射矩阵的"双峰"现象，或使平均次级中子能量过大而产生负KERMA(kinetic energy release in materials)因子。

Cosmic space-energy and cosmic gravitation pair is such coincidence, the spatial measurement of stable relative time-space cosmic energy is the 1/3 spatial measurement of cosmic time-space, the spatial curvature of stable relative time-space cosmic energy is the 2/3 spatial measurement of cosmic time-space.

宇宙空间能与宇宙引力的匹配是那样的吻合，宇宙能量的稳定相对时空的宇称为宇宙时空宇称的1/3，空间的曲率为宇宙时空宇称的2/3。

The stable structure of mass base__ the particle of photon most afterwards reach the verge of relative macrocosm, combine the relative space-energy of self, again come to do the quantum of stable spatial measurement radiate reach the relative vacuum of spatial curvature is 1/3 index of change level, return in the dark energy of cosmic energy, by the stable speed of (9/4)×107 m /s come to do random shift, later on again at random relatively gather.

基础质量的稳定结构--光微粒子最终到达相对的宏观世界的边沿，携带自己的相对空间能，再次成为稳定宇称量子辐射到更平直的空间的曲率指数为1/3的相对真空中去，回到宇宙能量的暗能量行列，以(9/4)×107m/s 的稳定速度成随机地移动，以后再随机地相对聚结。

This web site provides information about library, REPP introduction, energy policy, energy efficiency, renewable energy, etc.

本网站提供了图书馆、工程介绍、能源政策、能源效率、以及可再生能源信息等。

REPP's mission is to accelerate the use of renewable energy by providing credible information, insightful policy analysis, and innovative strategies amid changing energy markets and mounting environmental needs by researching, publishing, and disseminating information, creating policy tools, and hosting highly active, on-line, renewable energy discussion groups.

美国"可再生能源政策计划"始于1995年，任务是通过提供确切的信息、战略、政策分析，促进可再生能源的推广使用，保护环境。

You can do some assertiveness training.

你可以进行一些自信训练。

We were well on the path to making a rear-wheel-drive global platform," says Mays."

我们正致力于建立一个后轮驱动的平台，"Mays这样说道。"