1、. Many of these are very specialized, but the preponderance of paper making has been from soft wood and cotton or rags, with the bulk being wood-based.Paper from WoodD） In order to make wood into paper it needs to be broken down into fine strands. Firstly by powerful machinery and then boiled with s
2、trong alkalies such as caustic soda, until a fine pulp of cellulose fibers is produced. It is from this pulp that the final product is made, relying on the bonding together of the cellulose into layers. That, in a very small nutshell, is the essence of paper making from wood. However, the reality is
3、 rather more complicated. In order to give us our white paper and card, the makers will add bleach and other materials such as china clay and additional chemicals.E） A further problem with wood is that it contains a material that is not cellulose. Something called lignin. This is essential for the t
4、ree since it holds the cellulose fibres together, but if it is incorporated into the manufactured paper it presents archivists with a problem. Lignin eventually breaks down and releases acid products into the paper. This will weaken the bond between the cellulose fibers and the paper will become bri
5、ttle and look rather brown and careworn. We have all seen this in old newspapers and cheap paperback books. It has been estimated that most paper back books will have a life of not greater than fifty years. Not what we need for our archives.F） Since the lignin can be removed from the paper pulp duri
6、ng manufacture, the obvious question is why is it left in the paper? The answer lies in the fact that lignin makes up a considerable part of the tree. By leaving the lignin in the pulp a papermaker can increase his paper yield from a tree to some 95%. Removing it means a yield of only 35%. It is cle
7、arly uneconomic to remove the lignin for many paper and card applications.G） It also means, of course, that lignin-free paper is going to be more expensive, but that is nevertheless what the archivist must look for in his supplies. There is no point whatsoever in carefully placing our valuable artif
8、acts in paper or card that is going to hasten their demise. Acid is particularly harmful to photographic materials, causing them to fade and is some cases simply vanish!H） So, how do we tell a piece of suitable paper or card from one that is unsuitable? You cannot do it by simply looking, and rather
9、 disappointingly, you cannot always rely on the label. Acid-free might be true inasmuch as a test on the paper may indicate that it is a neutral material at this time. But lignin can take years before it starts the inevitable process of breaking down, and in the right conditions it will speed up eno
10、rmously.I） Added to this, as I have indicated earlier, paper may also contain other materials added during manufacture such as bleach, china clay, chemical whiteners and size. This looks like a bleak picture, and it would be but for the fact that there are suppliers who will guarantee the material t
11、hat they sell. If you want to be absolutely sure that you are storing in, or printing on, the correct material then this is probably the only way.J） Incidentally, acids can migrate from material to material. Lining old shoe boxes with good quality acid-free paper will do little to guard the contents
12、. The acid will get there in the end.Paper from RagK） Paper is also commonly made from cotton and rag waste. This has the advantage of being lignin-free, but because there is much less cotton and rag than trees, it also tends to be much more expensive than wood pulp paper. You will still need to pur
13、chase from a reliable source though, since even rag paper and card can contain undesirable additives.L） A reliable source for quality rag papers is a recognized art stockiest. Many water color artists insist on using only fine quality rag paper and board.M） The main lesson to learn from this informa
14、tion is that you cannot rely on purchasing archival materials from the high street. The only safe solution is to purchase from specialist suppliers. It may cost rather more, but in the end you will know that your important and valuable data and images have the best home possible.1. The corn-flake pa
15、cket is cheaper than high grade card.2. There are a lot of materials which can be used for making paper, but the superiority ones are soft wood, cotton and rags.3. During the whole manufacturing process, the final product is made from a pulp of cellulose fibres.4. In order to make white paper and ca
16、rd, the makers will add bleach.5. Liguin is essential for the tree but it will make paper easy to break.6. Many paper producers will preserve lignin during manufacture, because leaving the lignin will make more paper from a tree.7. Acid is particularly harmful to photographic materials.8. If the lig
17、nin is removed from the paper, the paper will be more expensive.9. Although free of lignin, paper made from cotton and rag waste can also cost more money than wood pulp paper because there is much less cotton and rag than trees.10. What we can learn from Paper from Rag is that you had better buy arc
18、hival materials from specialist suppliers.文章精要本文主要介绍了我们平常所见所用的纸的复杂性，通过介绍用木头和破布料造纸的过程，使我们对纸的类别、属性有了更深入的了解。1.B根据题干中的信息提示词cornflake packet,high grade card,可定位到文章第二段，该部分最后提到corn-flake packet在制造过程中比高等级的纸（high grade card）便宜.2.C根据题干中的信息提示词soft wood，cotton and rags，可定位到文章第三段最后一句。3.D根据题干中的信息提示词final product，
19、可将答案定位到D段，第二、三句提到最后的产品来源于纤维素纸浆。4.D根据题干中的信息提示词white paper and card，可将答案定位到D段，该部分最后提到为了得到白纸，纸张生产者在制造过程中添加了漂白粉和其他化学物质。5.E根据题干中的信息提示词essential for the tree，可将答案定位到E段，该部分提到木质素是木头的主要组成物，其作用是凝聚纤维素，但它会使纸张变得易碎。6.F根据题干中的信息提示词lignin，可将答案定位到F段，该部分最后提到许多纸张生产者在生产过程中会保留木质素，主要是因为它会增加树木的造纸产量。7.G根据题干中的信息提示词acid，可将答案定
20、位到G段，该部分最后提到酸对相纸的原料尤其不利。8.F根据题干中的信息提示词lignin和paper可定位到文章的F段，因为该段提到，如果在纸张的生产中去除木质素，将会降低树木出产纸张的量，由此可以知道，去除了木质素的纸张价格必定会更加昂贵。9.K根据题干中的信息提示词cotton and rag waste可定位到文章的K段，该部分告诉我们，尽管用棉花和破布料造的纸里没有木质素，但它们要比木制的纸贵很多，这是因为棉花和破布料的数量比树木少得多，由此可以得出答案。10.M根据题干中的信息提示词Paper from Ra9可定位到文章的最后一段，该部分提出最好到专业的供应商那里去买档案材料，由此
21、可以得出答案。长篇阅读2How to Make Attractive and Effective PowerPoint PresentationsA） Microsoft PowerPoint has dramatically changed the way in which academic and business presentations are made. This article outlines few tips on making more effective and attractive PowerPoint presentations.The TextB） Keep the
22、 wording clear and simple. Use active, visual language. Cut unnecessary wordsa good rule of thumb is to cut paragraphs down to sentences, sentences into phrases, and phrases into key words.Limit the number of words and lines per slide. Try the Rule of Five-five words per line, five lines per slide.
23、If too much text appears on one slide, use the AutoFit feature to split it between two slides. Click within the placeholder to display the AutoFit Options button （its symbol is two horizontal lines with arrows above and below）, then click on the button and choose Split Text between Two Slides from t
24、he submenu.C） Font size for titles should be at least 36 to 40, while the text body should not be smaller than 24.Use only two font styles per slideone for the title and the other for the text. Choose two fonts that visually contrast with each other. Garamond Medium Condensed and Impact are good for
25、 titles, while Garamond or Tempus Sans can be used for the text body.D） Embed the fonts in your presentation, if you are not sure whether the fonts used in the presentation are present in the computer that will be used for the presentation. To embed the fonts: （1） On the File menu, click Save As. （2
26、） On the toolbar, click Tools, click Save Options, select the Embed TrueType Fonts check box, and then select Embed characters in use only.E） Use colors sparingly; two to three at most. You may use one color for all the titles and another for the text body. Be consistent from slide to slide. Choose
27、a font color that contrasts well with the background.F） Capitalizing the first letter of each word is good for the title of slides and suggests a more formal situation than having just the first letter of the first word capitalized. In bullet point lines, capitalize the first word and no other words
28、 unless they normally appear capped. Upper and lower case lettering is more readable than all capital letters. Moreover, current styles indicate that using all capital letters means you are shouting. If you have text that is in the wrong case, select the text, and then click Shift+F3 until it change
29、s to the case style that you like. Clicking Shift+F3 toggles the text case between ALL CAPS, lower case, and Initial Capital styles.G） Use bold or italic typeface for emphasis. Avoid underlining, it clutters up the presentation.Dont center bulleted lists or text. It is confusing to read. Left align unless you have a good reason not to. Run “spell check” on your show when finished.The BackgroundH） Keep the background consistent. Simple, light textured backgrounds work well. Complicated textures make the c
