通过各种方法使酶分子的结构发生某些改变,从而改变酶的某些特性和功能的过程称为酶分子修饰酶分子是具有完整的化学结构和空间结构的生物大分子。酶分子的结构决定了酶的性质和功能。 正是酶分子的完整空间结构赋予酶分子以生物催化功能,使酶具有催化效率高、专一性强和作用 条件温和等特点。但是在另一方面,也是酶的分 子结构使酶具有稳定性较差、活性不够高和可能 具有抗原性等弱点 当酶分子的结构发生改变时将会引起酶的性质和功能的改变

所有的生物体在一定的条件下都能产生多种多样的酶。酶在生物体内产生的 过程,称为酶的生物合成。 经过预先设计,通过人工操作控制, 利用细胞(包括微生物、植物细胞和动物细胞)的生命活动,产生人们所需要的酶的过程,称为酶的发酵生产。 酶的发酵生产是现在酶生产的主要方法

Index absorptance HT-54 cylindrical geometry see non-planar geometry absorption HT-57 adiabatic 0-5.0-9 Diesel cycle 2A-4 adiabatic efficiency see efficiency diffusivity ht-22 adiabatic flame temperature 2C-7 dissipation 1C-10 drag HT-24 Biot number HT-30, HT-36 black body HT-56, HT-63 see also

2. B Power Cycles with Two-Phase Media (Vapor Power Cycles) [SB&vw-chapter 3, Chapter ll, Sections 11.1 to 11.7] In this section, we examine cycles that use two-phase media as the working fluid. These can be combined with gas turbine cycles to provide combined cycles which have higher efficiency

1. D: Interpretation of Entropy on the Microscopic Scale- The Connection between Randomness and entropy 1. D I Entropy Change in Mixing of Two ldeal gases Consider an insulated rigid container of gas separated into two halves by a heat conducting partition so the temperature of the gas in each part is the same. One side contains air, the other side another gas, say argon, both regarded as ideal gases. The mass of gas in each side is such

PaRT 1. THE SECOND LAW OF THERMODYNAMICS l.A. Background to the second Law of Thermodynamics AW 23-31(see IAW for detailed VwB&s references); VN Chapters 2, 3, 4 1-A. I Some Properties of engineering Cycles; Work and Efficiency As motivation for the development of the second law, we examine two types of processes that

1. C Applications of the Second Law N-Chapter6;VWB&S-8.1,8.2,8.5,8.6,8.7,8.8,9.6] 1. CI Limitations on the work that Can be supplied by a heat engine The second law enables us to make powerful and general statements concerning the maximum work that can be Q1

1、环境地质学概念(Concept) 是认识“系统环境”的一门综合性学科, 是研究环境科学、地质科学,系统了解地球本身的一门基础科学 。人类只有一个地球,共同的家园。 2、环境地质学学习意义(why study it) 不了解地球的学者不算一个完美的学者,环境地学知识能使其它 学科,在设计施工、决策上站在“地球环境”的高度上考虑问题 3、授课对象(who study it)

一、选择合适的答案,填入空内。只需填入A、B或C (1)功率放大电路的最大输出功率是在输入电压为正弦波时,输出基本不失真情况下,负载上可能获得的最大 A.交流功率 B.直流功率 C.平均功率

一、判断下列说法是否正确,凡对的在括号内打“√”,否则打“×”。 (1)现测得两个共射放大电路空载时的电压放大倍数均为-100,将它们连成两级放大电路,其电压放大倍数应为10000。() (2)阻容耦合多级放大电路各级的Q点相互独立,()它只能放大交流信号。()