下列哪些参数能够更好的反映水体污染和自净程度()。
A. P/H指数
B. COD
C. BIP
D. 氧浓度昼夜变化幅度
参考答案:A
采用分段灌注模型是为了()
A.模型美观
B.提高模型强度和降低材料成本
C.提高灌注模型的精确度
D.防止产生体积膨胀
E.防止产生气泡
another; like; area; those; health; there; angry; sound; look; art; more; way Why do so many people around the world love Chinese cooking In China, cooking is an (66) , just like music, dance and painting. However, there is (67) than just one kind of Chinese food. Different areas in China have special (68) of cooking because of the differences in weather and geography. Traditional Chinese doctors believe we need a balance of yin and yang to be (69) Maybe you should eat yang foods, (70) beef when you feel weak or tired. And you should eat yin foods like tofu while you are too stressed out or (71) The Chinese believe people who eat a balanced diet should be healthier than (72) who only eat foods that taste good. (73) is much more to Chinese food than just taste. Behind many dishes are traditions with deep meaning. One Chinese food tradition is to eat long noodles on your birthday as a symbol of long life. (74) traditional food, yuan xiao, suggests that a family will always stay together. On the Spring Festival, people often eat fish, because yu (75) like the word meaning "more than enough". From north to south, east to west, people are sure to find some kind of Chinese food to suit their taste and interest.