Chlorotoluene Benzyl chloride Of this group only benzyl chloride is not an aryl halide; its halogen is not attached to the aromatic ring but to an sp-hybridized carbon. Benzyl chloride has the weakest carbon-halogen bond, its measured carbon-chlorine bond dissociation energy being only 293 kJ/mol (70 kcal/mol). Homolytic cleavage of this bond produces a resonance-stabilized benzyl radical

he major classes of organic compounds common to living systems are lipids, pro- teins, nucleic acids, and carbohydrates. Carbohydrates are very familiar to us- we call many of them\sugars.\ They make up a substantial portion of the food we eat and provide most of the energy that keeps the human engine running. Carbohy- drates are structural components of the walls of plant cells and the wood of trees. Genetic

Interactions within a package system refer to the exchange of mass and energy between the packaged food, the packaging material and the external environment. Food-packaging interactions can be defined as an interplay between food, packaging, and the environment, which produces an effect on the food, and/or package (Hotchkiss, 1997). Mass transfer processes in packaging systems are normally referred to as permeation, migration and absorption(fig8.1). Permeation is the process resulting from two basic mechanisms

Let vs=100 cos a t V in the circuit shown in Fig. 9-12.(a) Find the equivalent parallel RLC circuit and then determine resonant frequency @r, Q, and v(t).(b) Find i, (t),i2(t), and i3(t) (c)Calculate the average power loss in the 10 kQ2 resistor and the maximum energy stored in the inductor

In the chapter we shall introduce some two-terminal element which have properties, which are quite different than those of the resistor. These elements are the inductor and capacitor. The inductor and capacitor are passive elements, which are capable of storing and delivering finite amounts of energy

When initial energy is present in a circuit, the Laplace transform method may be used to obtain the complete response. The first is the more fundamental, for it involves writing the differential equations for the network and then taking the Laplace transform of those equations

Ohm's law states that voltage across many types of conducting materials is directly proportional to the current flowing through the material. U= Ri or R= i R--resis tance()( linear resistor) The resistor is a passive element that cannot deliver power or store energy

一、将下列专业术语译成汉语(每个1分,共10分) 1. agroecology 2. ecosystem 3. energy flow 4. food chain

6.1 An Introduction to Enzymes 191 H20 in the presence of oxygen is a highly exergonic 6.2 How Enzymes Work 193 process, releasing free energy that we can use to think an I 6.3 Enzyme Kinetics as an Approach to Understanding main on the shelf for years without any obvious con-

In this lecture, we will derive expressions for the angular momentum and kinetic energy of a 3D rigid body. We shall see that this introduces the concept of the Inertia Tensor. Angular Momentum We start form the expression of the angular momentum of a system of particles about the center of mass