问题 问答题 简答题

什么是导湿性和导湿温性?

答案

参考答案:

导湿性:干制过程中潮湿食品表面水分受热后首先有液态转化为气态,即水分蒸发,而后,水蒸气从食品表面向周围介质扩散,此时表面湿含量比物料中心的湿含量低,出现水分含量的差异,即存在水分梯度。水分扩散一般总是从高水分处向低水分处扩散,亦即是从内部不断向表面方向移动。这种水分迁移现象称为导湿性。

导湿温性:干燥时,物料表面受热高于它的中心,因而在物料内部会建立一定的温度梯度。温度梯度将促使水分(不论液态或气态)从高温处向低温处转移。这种现象称为导湿温性。导湿温性是在许多因素影响下产生的复杂现象。

完形填空

“Hi! John.” Mary ran towards me with a bright smile, saying, “I’m going to have a dance performance tonight. I hope you’ll come. Here is the ticket. Don’t forget!” Then she    41  in a hurry.
“What? Dance? Is that    42  ?” I asked myself. Mary was not such kind of girl. She was quite common one. I had never seen her wearing colorful clothes. In fact, she really did not know    43   to dress up. What a terrible thing!
“I should go to, I must go to.” I thought.
I arrived at the hall with the ticket, found my seat and sat down. Her performance was the seventh one. I knew I would have a    44   time before her turn, for I had no sense of art,    45   her performance was worth(值得)watching, no matter how long I would wait.
Time went    46  , I tried my best not to fall asleep.
Just then, came the words, “Let’s welcome the next exciting dance – Latin!”
Hearing this, I opened my eyes as large as possible,    47   to lose anything. Wearing a golden and shiny skirt, Mary appeared. She danced with a sweet smile, looking like a pretty butterfly flying … I could    48   believe my eyes.
After all the performance ended, I    49   her at the gate.
“Hi!” She stood in front of me with her crystal(水晶) shoes. “How do you feel?”
“Fantastic!” I answered.
“Ha, ha. I knew it would be.” She could not hide her excitement, laughing    50  a child.
At that time, I realized that every girl has a pair of special shoes which are like the crystal shoes of Cinderella.
小题1:
A.cameB.jumpedC.leftD.moved
小题2:
A.possibleB.luckyC.funnyD.careful
小题3:
A.why B.whereC.whenD.how
小题4:
A.greatB.shortC.hardD.relaxing
小题5:
A.orB.soC.butD.and
小题6:
A.quicklyB.slowlyC.safelyD.easily
小题7:
A.hopingB.fearingC.planningD.hating
小题8:
A.seriouslyB.hardlyC.nearlyD.certainly
小题9:
A.waited forB.looked forC.paid forD.cared for
小题10:
A.asB.likeC.forD.at
多项选择题