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
Natural flavorings and fragrances are often costly and limited in supply. For example, the vital ingredient in a rose fragrance
Natural flavorings and fragrances are often costly and limited in supply. For example, the vital ingredient in a rose fragrance
admin
2008-01-10
27
问题
Natural flavorings and fragrances are often costly and limited in supply. For example, the vital ingredient in a rose fragrance is extracted from natural rose oil at a cost of thousands of dollars a pound; an identical synthetic substance can be made for 1% of this cost. Since the early twentieth century, success in reproducing these substances has created a new industry that today produces hundreds of artificial flavors and fragrances.
Some natural fragrances are easily synthesized; these include vanillin, the aromatic ingredient in vanilla, and benzaldehyde, the aromatic ingredient in wild cherries. Other fragrances, however, have dozens, even hundreds of components. Only recently has it been possible to separate and identit3, these ingredients by the use of gas chromatography and spectroscopy. Once the chemical identity is known, it is often possible to synthesize them. Nevertheless, some complex substances, such as the aroma of fresh coffee, have still not been duplicated satisfactorily.
Many of the chemical compounds making up these synthetics are identical to those found in nature, and are as harmless or harmful as the natural substances. New products must be tested for safety, and when used in food, must be approved by the U.S. Food and Drug Administration.
The availability of synthetic flavors and fragrances has made possible a large variety of products, from inexpensive beverages to perfumed soap to used cars with applied "new car odor."
According to the passage, all the following are easier to synthesize EXCEPT ______
选项
A、aromatic ingredient in vanilla
B、vanilla
C、aromatic ingredient in wild cherry
D、the flavor of fresh coffee
答案
D
解析
本题可用排除法。见第二段第一句:Some natural fragrances are easily synthesized; these include vanillin,the aromatic ingredient in vanilla,and benzaldehyde,the aromatic ingredient in wild cherries.选项A、B、C的内容均被提及,因此除外的选项只有D,所以D为答案。(本题答案也可用下一题的推断法推出)
转载请注明原文地址:https://kaotiyun.com/show/oP5O777K
本试题收录于:
CATTI三级笔译综合能力题库翻译专业资格(CATTI)分类
0
CATTI三级笔译综合能力
翻译专业资格(CATTI)
相关试题推荐
UniversityGeographyFieldTripExampleTime:nextweek(atwo-daytrip)Destination:theW
CUSTOMERQUOTATIONFORMExampleCountryofdestination:SouthAfricaName:Roy【L1】___
CUSTOMERQUOTATIONFORMExampleCountryofdestination:SouthAfricaName:Roy【L1】___
TheseatofFrance’sNorthAmericanholdingsintheeighteenthcenturywasQuebec,andtheFrenchheritage______dominantthere
TheSpanish(claiming)titleto(allof)NorthAmericaandestablishedthe(oldestcity)intheUnitedStates,St.Augustine,Flo
Managersoftenreceiveconsiderabletrainingintile"technical"aspectsoftheirjobs______verylittleinthe"peoplenanagem
Gourdswere(introduced)towhatisnowthesouthwesternUnitedStatesby(earliest)peoples(who)migratednorth(from)Mesoame
A、TheycharacterizestagesinWright’scareerB、WrightdiedwhiletheywerebeingconstructedC、TheywereWright’searliestbuil
Sinceprehistoricpeoplefirstappliednaturalpigmentstocavewalls,______havepaintedtoexpressthemselves.
WhatnaturalfeaturesofManitoba-doestheprofessordiscuss?Clickontwoanswers.
随机试题
背景某城市图书馆工程项目,结构主体已施工完成,目前进行装饰装修工程的施工,其中门窗子分部工程中有塑料门窗安装、特种门安装、门窗玻璃安装三个分项工程,在上个月的施工中,主要技术经济参数如下表所示。问题施工项目成本控制内容。
电子焊接中一般焊接剂是什么?助焊剂是什么?
下列哪项病史不是慢性盆腔炎的诊断依据
A、人参B、黄芪C、山药D、党参E、白术常用于气虚欲脱,脉微欲绝的危重证候的药物是
护士遵医嘱为患者缓慢静脉推注10%葡萄糖酸钙10ml,推注约4ml时发现有阻力,局部略肿胀,且抽吸无回血。判断可能的原因是
用电设备台数较少,各台设备容量相差悬殊时,宜采用(),一般用于支干线和配电屏(箱)的负荷计算。
保持国际收支的基本平衡,政策走向是()。
关于程序,正确的理解是_______。
二战期间,下列四次战役的时间先后顺序是()①莫斯科战役②诺曼底登陆③不列颠之战④阿拉曼战役
VisualPerspectivePerspectiveinartisthewaythatartistsrepresentthree-dimensionalobjectsonthetwodimensionsoftheir
最新回复
(
0
)