首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
外语
The earliest process of making paper was done almost 5,000 years ago in Egypt and the Nile Valley. In those days, paper was made
The earliest process of making paper was done almost 5,000 years ago in Egypt and the Nile Valley. In those days, paper was made
admin
2016-09-21
47
问题
The earliest process of making paper was done almost 5,000 years ago in Egypt and the Nile Valley. In those days, paper was made from strips of the papyrus plant.
Modern paper-making began in China about 2,000 years ago. This process produced paper from cloth, straw, wood or the bark of trees. The raw materials are struck over and over until they become loose. Then they are mixed with water.
After the water has been removed, the flat, thin form remaining is permitted to dry. This becomes a sheet of paper.
Large machines started to be used for making paper near the end of the 16th century. Today, paper-making is a big business. But it is still possible to make paper by hand, since the steps are the same as using big machines.
You should choose paper with small amounts of printing. Old envelopes are good for this reason. Colored paper also can be used, as well as small amounts of newspaper. Small pieces of rags or cloth can be added. These should be cut into pieces about 5 centimeters by 5 centimeters.
Everything is placed in a container, covered with water, and brought to a boil. It is mixed for about 2 hours with some common chemicals and then allowed to cool. Then it is left until most of the water dries up. The substance left, called pulp, can be stored until you are ready to make paper.
When you are ready, the pulp is mixed with water again. Then the pulp is poured into a special box or mold. The mold is made of small squares of wire that hold the shape and thickness of the paper. To help dry the paper, the mold lets the water flow through the small wire squares.
After several more drying steps, the paper is carefully lifted back from the mold. It is now strong enough to be touched.
The paper is smoothed and pressed to remove trapped air. You can use a common electric iron used for pressing clothes.
Whether the paper is strong enough to be touched is determined by _____.
选项
A、how long the pulp is stored
B、how thick the paper is
C、how much water remains
D、what type of chemicals are used
答案
C
解析
倒数第2段提及要经过“多次干燥处理”,才能把纸取出,可见,纸是否足够坚韧以便取出,取决于纸浆中含有的水分的多少,因此,本题应选C。
转载请注明原文地址:https://kaotiyun.com/show/BfY7777K
0
大学英语四级
相关试题推荐
TheNewYearpaintingisaformofancientfolkpaintingthatwasdevelopedtocelebratethetraditionalChineseLunarNewYear.
Aninterpersonalrelationshipisarelativelylong-termassociationbetweentwoormorepeople.Thisassociationmay【B1】______e
A、Checkthetimetable.B、Gototherailwaystationearlier.C、Travelonalatertrain.D、Cancelthetripearlier.C女士说恐怕她们要赶不上三点
Inacompetitiveeconomy,theconsumerusuallyhasthechoiceofseveraldifferentbrandsofthesameproduct.Yetunderneathth
Inacompetitiveeconomy,theconsumerusuallyhasthechoiceofseveraldifferentbrandsofthesameproduct.Yetunderneathth
Weoftenpassonlittlebitsofinformationtoourchildren,notknowingiftheyaretrue,andonlybecausetheywere【B1】_______
A、Speakingwithaproperaccent.B、Wearinganofficialuniform.C、Makingfriendswiththem.D、ShowingthemhisID.D
Schoolshootingsareinthenewsagain.AnOhioteenageropenedfireonfiveclassmates,killingthreestudentsandinjuringtwo
Theygotooneoftheworld’smostprestigiousuniversitiesandpridethemselvesontheirsuperiorintellectbutalmosthalfof
InAmericatherearenumeroustypesofdoctors,fromgeneralpractitioners(从业者)tospecialists.MostpeopleintheU.S.havea"p
随机试题
钎料的熔点应比母材金属的熔点高40~60℃。
不符合渗出液实验室检查结果的()。
患者,女,45岁。失眠2年,经常多梦少寐,入睡迟,易惊醒,平常遇事惊怕,多疑善感。气短头晕,舌淡,脉弦细。治疗除取主穴外。还应加()
9个月小儿,身高80cm,体重15kg,每天户外活动2~3h,近日出现多汗、烦躁、夜惊。查体:枕秃,轻度肋缘外翻。该患儿患佝偻病的可能原因是
患者,女性,65岁,因阵发性胸闷5年,持续胸痛6小时收入院。入院时血压为150/90mmHg,诊断为急性前壁心肌梗死。支持诊断的心电图改变为()
A.促甲状腺素B.绒促性素C.破伤风人免疫球蛋白D.结合雌激素E.重组人促红素在运输中应冷库贮存并避免冻结的药品是
下列各项中,属于《仲裁法》规定的仲裁范围的是()。(2014年)
自2007年2月1日起,各省税务机关可按规定对房地产开发企业土地增值税进行清算。清算以国家有关部门审批的房地产开发项目为单位,对于分期开发的项目,应将各期项目合并为一个单位清算。()
从年画的艺术形式特点上,可以感受到:饱满的构图、鲜明的形象似乎潜藏有盼望大团圆、祈愿丰收和吃饱饭等意思;挺拔的线条,反映出健康、有力的含义;鲜明的色彩,体现出火红喜庆的意思。中国人偏爱红色,它象征太阳、温暖、热闹、吉祥等意思,所以年画上,人们挂红灯笼、穿红
Africa’selephantsaredividedbetweenthesavannahsofeasternandsouthernAfricaandtheforestsofcentralAfrica.Somebiol
最新回复
(
0
)