1.设x)在(-∞,+∞)内可导,且对任意x1,x2,x1>x2时,都有fx1)>fx2),则 (a)对任意x,f(x)>0(b)对任意xf\(x)≤0 (c)函数f(一x)单调增加 (d)函数f(一x)单调增加

1. 1 Promotion of exports from developing countries to the European Union(EUand other industrialized countries-al n overview Supplying safe and high quality foods is more important than ever, as importers of food products demand safe food in compliance with strict hvgiene rules Quality improvement, however, is a continuous process The present concems in quality with respect to insects, extraneous matter, moisture, ash, micro-organisms insects, mites, mycotoxin, pesticide residues, heavy metals, non permitted colors, animal excreta, etc. will be

4.1 Staff training programme including records 4.1.1 All employees should be informed in writing of their legal obligations and the company's policy on personal hygiene prior to commencing work, with periodic updates as necessary. It is recommended that a standard induction course explaining the relevant legislation is designed and used by all QA managers for new staff

1写出苯甲醛与下列试剂反应的主要产物。 (1). (CH,CO)/ NaAc. A Ho (2). NaC, /NH,) (3). CHNO, /HO (4).CH3CHO/稀OH (5).CCOCH3OH△(6)浓OH

一、影响传热膜系数的因素 1、流体流动状态 层流:忽略自然对流时,层流底层=r湍流:主要热阻在层流层,Re↑,边界层减薄,a(注意管件、内构件影响,Re层2000?)

例题用板式塔实现如下分离任务 已知:惰性气流量为V(kmol/h),溶质初始含量 摩尔比Y1=0.1,溶剂流量为L(kmol/h),新鲜 溶剂中溶质含量摩尔比X2=0(纯溶剂)操作温 度和压力下的平衡关系为Y=0.5X.假定V=L 要求:尾气中溶质A含量Y2≤0.01. 试求:(1)溶剂出口浓度X1

1、单相半波可控整流电路对电感负载供电,L=20mH,U2=100,求当a=0°和60°时的负载电 流I,并画出ud与波形。 2、图1为具有变压器中心抽头的单相全波可控整流电路,问该变压器还有直流磁化问题吗?试 说明: ①晶闸管承受的最大正反向电压为22U2 ②当负载为电阻和电感时,其输出电压和电流的波形与单相全控时相同

一、单项选择题(在下列每小题四个备选答案中选出一个正确答案,并将其字母标号填入“答卷”纸上相应题号的括号中。每小题1分,共20分) 1.在音节zi、ji、zhi中,i、一i(前)、i(后)是 A.一个音位的不同变体 B.两个音位,i是一个音位,一i(前)、一i(后)是一个音位 C.两个音位,i和一i(前)是一个音位,一i(后)是一个音位 D.三个音位

8.1 INTRODUCTION The purpose of this chapter and Chap. 9 is to develop shock-wave theory, thus giving us the means to calculate the changes in the flow properties across a wave.本章和第九章的目的是推导激波理论,因而得出计算通过激波的流动特性变化量的公式

1重组DNA技术与基因工程的基本概念 A重组DNA技术的基本定义 B基因工程的基本定义 C重组DNA技术与基因工程的基本用途 D基因工程的基本形式