20060708舊文

In addition to use in the lab, ethanol is a popular fuel alternative and gasoline additive. Because it is flammable, ethanol can be prohibitively expensive to ship, so it may make sense to distill your own. Anyone can have a still, but be advised you may need to get a permit in order to make ethanol.

Difficulty: Easy

Time Required: 3 - 10 days, sometimes longer

Here's How:

If you are starting with whole corn, you first need to convert the cornstarch into sugar by 'sprouting' the corn. Place the corn in a container, cover it with warm water, and drape a cloth over the container to prevent contamination and conserve heat. Ideally, the container will have a slowly draining hole at the bottom. Add warm water from time to time as the liquid level falls. Maintain the setup ~3 days or until the corn has sprouts about 2 inches long.

Allow the sprouted corn to dry. Then grind it into meal. Alternatively, start with cornmeal. Other grains can be prepared in much the same way (e.g. rye mash).

Mash or mush is made by adding boiling water to the corn meal. The mash is kept warm to start the fermentation process. Yeast is added, if available (half pound yeast per 50 gallons of mash, for example), and sugar (variable recipe). With yeast, fermentation takes about 3 days. Without yeast, fermentation could require more than 10 days. The mash is ready to 'run' once it stops bubbling. The mash has been converted into carbonic acid and alcohol. It is called 'wash' or 'beer' or 'sour mash'.

The wash is placed into a cooker, which has a lid that is pasted shut, so that it has a seal which can be blown off should internal pressure become too great. At the top of the cooker, there is a copper pipe, or 'arm' that projects to one side and tapers down from a 4-5 inch diameter to the same diameter as the 'worm' (1 to 1-1/4 inch). The 'worm' could be made by taking a 20 ft length of copper tubing, filling it with sand and stopping the ends, and then coiling it around a fence post.

The sand prevents the tubing from kinking while being coiled. Once the worm is formed, the sand is flushed out of the tube. The worm is placed in a barrel and sealed to the end of the arm. The barrel is kept full of cold, running water, to condense the alcohol. Water runs in the top of the barrel and out an opening at the bottom. A fire is maintained under the cooker to vaporize the alcohol in the wash.

The ethanol vaporizes at 173°F, which is the target temperature for the mixture. The spirit will rise to the top of the cooker, enter the arm, and will be cooled to the condensation point in the worm. The resulting liquid is collected at the end of the worm, traditionally into glass jars. This fluid will be translucent, and about the color of dark beer.

The very first liquid contains volatile oil contaminants in addition to alcohol. After that, liquid is collected. The containers of liquid collected from over the wash are called 'singlings'. Liquid collected toward the end of this run is called 'low wine'. Low wine can be collected and returned to the still to be cooked again. The initial collections are higher proof than those collected as the distillation progresses.

The singlings tend to have impurities and require double-distillation, so once the low wine has been run to the point where a tablespoon or so thrown on a flame won't burn (too low proof), the heat is removed from the still and the cooker is cleaned out. The liquid remaining in the still, the 'backings' or 'slop', can be recovered and poured over new grain (and sugar, water, and possibly malt) in a mash barrel for future distillations. Discard mash after no more than eight uses.

The singlings are poured into the cooker and the still is returned to operation. The initial collections can approach pure alcohol (200 proof), with the end collections, using the flash test on the flame, at about 10 proof.

The desired proof depends on the application. The highest proof usually obtained from a still is 190 proof. For using alcohol as a fuel alternative, for example, addition purification with a sieve may be required to obtain 200 proof ethanol.

是非無判斷題是雅思閱讀考試的經典題型，雖然今年的題量相對減少，但是仍是復習備考時應關注的題型。

首先應該注意看清是TRUE還是YES, 本篇是TRUE/ FALSE/ NOT GIVEN

解題步驟：

1. 速讀問題的句子，找出考點詞（容易有問題的部分）。考點詞：比較級，最高級，數據（時間），程度副詞，特殊形容詞，絕對化的詞（only, most, each, any, every, the same as等）

2. 排除考點詞，在余下的詞中找定位詞，去原文定位。

3. 重點考察考點詞是否有提及，是否正確。

TRUE的原則是同義替換，至少有一組近義詞。

FALSE是題目和原文截然相反，不可共存，通常有至少一組反義詞。

NOT GIVEN原文未提及，不做任何推斷，尤其多考察題目的主語等名詞在原文是否有提及。

劍5 Test3 Passage1

Summary;

Multiple Choice

食物對非洲M地學生的影響，教育與食物的關系。提供食物給M地的學校后，其入學率與學生的考試通過率均提高了，而且還促進了孩子們的智力發育。

20100710舊文

Heading題型做題步驟：

1. 讀題目要求，注意是將heading前的序號寫在答題卡上。

2. 劃去Example項，在Lists of headings中將例子的標題劃去，同時將對應段落在文章中劃去，以免做題時重復找。

3. 在給出的標題中劃出關鍵詞，以名詞為主。

4. 讀文章段落，主要讀段首和段尾，找出主題句。

5. 將段落主題句和標題相比較，選出答案。

注意事項：

1. 在找主題句的時候，段首不一定是段落的第一句，很多時候，尤其是第二段及以后的段落，第一句往往是對上一段的概括，第二句第三句才是主題句。

2. 如果本段有however, but等轉折詞匯以及also, although等，主題句即作者的中心在其后面。

3. 如果某段中重復出現標題中的某個關鍵詞，也可以判定此段的標題即是含有這個關鍵詞的標題。

Yes/No/Not Given;

Matching

講澳大利亞的博物館NGV, 先講了一下1968年的時候博物館什么樣子，接著講了現在的那個博物館什么樣子。

Matching題分為一方是特殊定位詞的配對，分類題，段落配標題，段落細節信息定位。一方是特殊定位詞的配對主要有人名配觀點，時間配事件，地點配事件。這種題目在做的時候要注意以下幾點：

1. 審題，讀Instruction。一般來說，都會有You may use any letter more than once. 遇到這行字時，提醒考生一般本題中肯定會有一個字母用兩次的，而且只有一個字母會重復。

2. 迅速瀏覽人名，在文章中圈出人名。

3. 通讀配對另一方，劃出關鍵詞。

在文章中圈出的人名旁找相應信息與關鍵詞進行匹配。

一方不是特殊定位詞時，需要將配對雙方都要通讀，并劃出核心詞匯，以名詞為主。同時這類題目要放在本篇文章的最后做。