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楼主
发表于: 2007-11-26 13:04
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精选阅读词汇笔记（三） 精选阅读词汇笔记（三）
-------------------------------------------------------------------------------- P7 The elements other than hydrogen and helium exist in such small quantities that it is accurate to say that the universe is somewhat more than 25 percent helium by weight and somewhat less than 75 percent hydrogen. Astronomers have measured the abundance of helium throughout our galaxy and in other galaxies as well. Helium has been found in old stars, in relatively young ones, in interstellar gas, and in the distant objects known as quasars. Helium nuclei have also been found to be constituents of cosmic rays that fall on the earth (cosmic "rays"are not really a form of radiation; they consist of rapidly moving particles of numerous different kinds). It doesn't seem to make very much difference where the helium is found. Its relative abundance never seems to vary much. In some places, there may be slightly more of it: in others, slightly less, but the ratio of helium to hydrogen nuclei always remains about the same. Helium is created in stars. In fact, nuclear reactions that convert hydrogen to helium are responsible for most of the energy that stars produce. However, the amount of helium that could have been produced in this manner can be calculated, and it turns out to be no more than a few percent. The universe has not existed long enough for this figure to be significantly greater. Consequently, if the universe is somewhat more than 25 percent helium now, then it must have been about 25 percent helium at a time near the beginning. However, when the universe was less than one minute old, no helium could have existed. Calculations indicate that before this time temperatures were too high and particles of matter were moving around much too rapidly. It was only after the one- minute point that helium could exist. By this time, the universe had cooled sufficiently that neutrons and protons could stick together. But the nuclear reactions that led to the formation of helium went on for only a relatively short time. By the time the universe was a few minutes old, helium production had effectively ceased. -------------------------------------------------------------------------------- elements : n. 原理,基础 helium : n. 氦 quantity : n. 量,数量,总数 accurate : a. 正确的,精确的 abundance : n. 丰富,充足,大量 galaxy : n. 银河,星系,一群显赫的人物 relatively : ad. 相对地 interstellar : a. 星际的 quasar : n. 恒星状球体,半星球体,类星球体 nuclei : n. nucleus 的复数形nucleus : n. 核心,核子,原子核,中坚 constituent : n. 成分,选民,构成物;a. 构成的,组织的,有选举权的 radiation : n. 放射线 consist : vi. 组成,存在,一致 particle : n. 粒子,点,极小量 ratio : n. 比,比率 convert : n. 皈依者,改变宗教者;vt. 使改变信仰,转换,兑换,倒置;vi. 皈依 responsible : a. 有责任的,负责的,责任重大的,可靠的 manner : n. 样子,礼貌,风格 significant : a. 重要的,有效的,有含义的,暗示的,非偶然的 consequently : ad. 结果 indicate : vt. 指出,显示,象征,指示 particle : n. 粒子,点,极小量 sufficient : a. 充分的,足够的 neutron : n. 中子 proton : n. 质子 stick : n. 棍,棒,刺,茎,枯枝,条状物;vt. 插于,刺入,钉住,使停止,伸出,粘贴;vi. 粘住,停留,坚持,陷住,伸出 effectively : ad. 有效地,有力地,实际上 cease : n. 停止;vi. vt. 停止,终了 -------------------------------------------------------------------------------- P8 Are organically grown foods the best food choices?The advantages claimed for such foods over conventionally grown and marketed food products are now being debated. Advocates of organic foods ----- a term whose meaning varies greatly --- frequently proclaim that such products are safer and more nutritious than others. The growing interest of consumers in the safety and nutritional quality of the typical North American diet is a welcome development. However, much of this interest has been sparked by sweeping claims that the food supply is unsafe or inadequate in meeting nutritional needs. Although most of these claims are not supported by scientific evidence, the preponderance of written material advancing such claims makes it difficult for the general public to separate fact from fiction. As a result, claims that eating a diet consisting entirely of organically grown foods prevents or cures disease or provides other benefits to health have become widely publicized and form the basis for folklore. Almost daily the public is besieged by claims for "no-aging" diets, new vitamins, and other wonder foods. There are numerous unsubstantiated reports that natural vitamins are superior to synthetic ones, that fertilized eggs are nutritionally superior to unfertilized eggs, that untreated grains are better than fumigated grains, and the like. One thing that most organically grown food products seem to have in common is that they cost more than conventionally grown foods. But in many cases consumers are mislead if they believe organic foods can maintain health and provide better nutritional quality than conventionally grown foods. So there is real cause for concern if consumers, particularly those with limited incomes,distrust the regular food supply and buy only expensive organic foods instead. -------------------------------------------------------------------------------- organically : ad. 有机性地,器官上地,有组织地 choice : n. 选择,精选品,选择权;a. 精选的,挑三拣四的,可选的 advantage : n. 优点,便利,好处,优势;vt. 有助于 claim : n. 要求,要求权,断定,权利;vt. 要求,请求,主张;vi. 提出要求,主张,断言 conventionally : ad. 照惯例,照常套,照老例 debate : n. 辩论,讨论;vi. vt. 争论,辩论 advocate : n. 提倡者,拥护者;vt. 主张,提倡 frequently : ad. 时常,屡次,经常地 proclaim : vt. 宣布,公告,宣言,表明,赞扬 nutritious : a. 有营养成分的,营养的 consumer : n. 消费者 quality : n. 品质,特质,才能,质量;a. 优质的;n. 品质 typical : a. 典型的,象征性的 diet : n. 日常饮食,议会;vt. 照规定饮食;vi. 忌食 spark : n. 火花,火星,闪光,情郎,花花公子,活力,电信技师,朝气,瞬间放电;vi. 闪烁,闪光,发火花,求婚;vt. 发动,鼓舞,使有朝气,求婚 unsafe : a. 不安全的,不安稳的,危险的 inadequate : a. 不充分的,不适当的 evidence : n. 证据,迹象 preponderance : n. 重量的优势,优势,优越 separate : n. 分开,抽印本;a. 分开的,各别的,单独的,分隔的,灵魂的;vi. 分开,隔开,分居;vt. 使分离,使分开,区分,使分居 fiction : n. 小说,虚构的故事,法律的拟制 consist : vi. 组成,存在,一致 prevent : vt. vi. 预防,防止,避免,阻止,妨碍 cure : n. 治疗,治愈,治疗法,怪人;vt. 治疗,改正,使硫化,加工,腌制;vi. 受治疗,被加工处理,被硫化 disease : n. 疾病,弊病 benefit : n. 利益;vt. 有益于;vi. 受益 publicize : vt. 宣传,公布,广告 basis : n. 基础,主要成分 folklore : n. 民俗学,民间风俗,民间传说 besiege : vt. 围攻,包围 aging : n. 老化,陈化 vitamin : n. 维他命,维生素 wonder : n. 奇迹,惊奇,惊愕;vt. 惊奇,想知道;vi. 惊讶,怀疑 numerous : a. 很多的,数目众多的,多数的 unsubstantiated : a. 未经证实的,不能肯定的 superior : n. 长者,高手,上级;a. 上好的,出众的,高傲的 synthetic : n. 合成物质;a. 综合性的,人造的 fertilize : vt. 施肥,使丰饶,使受精 nutritional : adj. 某 种食物的营养价值 untreated : adj. 未处理的,未处治的 grain : n. 谷粒,颗粒,谷类,纹理,本质;vt. vi. (使)成谷粒 fumigate : vt. 熏制 conventionally : ad. 照惯例,照常套,照老例 mislead : vt. 误导 believe : vt. vi. 相信 organic : a. 器官的,有机的,组织的,根本的 concern : n. 关心,忧虑;vt. 与...有关,使担心,挂虑 limited : a. 有限制的,有限的,少的;n. 高级快车 distrust : n. 不信任;vt. 不信任 instead : ad. 改为,抵作,更换,替代 -------------------------------------------------------------------------------- P9 Marjorie Rice was an unlikely candidate for the role of mathematical innovator. She had no formal education in mathematics save a single course required for graduation from high school in 1939. Nonetheless, in 1975 she took up a problem that professional mathematicians had twice left for dead , and showed how much life as in it still. The problem was tessellation , or tiling of the plane , involves taking a single closed figure a triangle, for example, or a rectangle and fitting it together with copies of itself so that a plane is covered without any gaps or overlap. A region of this plane would look rather like a jigsaw puzzle whose pieces are all identical. Rice worked primarily with polygons, which consist only of straight lines. More specifically, she worked with convex polygons , in which the line joining any two points on the polygon lies entirely within the polygon itself or on one of its edges(A five-pointed star, for example, does not qualify as a convex polygon.) By the time Rice took up tiling, its basic properties had been established. Obviously, any square can tile the plane, as many kitchen floors have demonstrated. Equilateral triangles are also a fairly clear-cut case. There is one other regular polygon(a polygon whose angles, and sides, are equal) that can tile the plane: the hexagon . This fact was established by the ancient Greeks but had long before been exploited by honeybees in building their honeycombs. And what of irregular polygons? As it turns out any triangle or quadrilateral , no matter how devoid of regularity, will tile the plane. On the other hand, no convex polygon with more than six sides can do so, and the three classes of convex hexagons that can were uncovered by the end of the First World War. So the only real question left by the time Marjorie Rice began her work was which convex pentagons tile the plane. -------------------------------------------------------------------------------- unlikely : a. 不太可能的 candidate : n. 候选人,投考者 mathematical : a. 数学的,精确的 innovator : n. 改革者,刷新者 formal : a. 正式的,形式的,礼仪的;n. 正式的社交活动 be left for dead : 没有办法解决的难题 tessellation : n. 镶嵌装饰,棋盘形布置,镶嵌式铺装 tiling : n. 盖瓦,铺瓷砖,瓦类,花砖 plane : n. 平面,飞机,水准;a. 平的,平面的,平坦的;vt. 将...刨平,刨平;vi. 翱翔,乘飞机旅行,刨 involve : vt. 包括,使陷于,潜心于,包围 rectangle : n. 长方形,矩形 gap : 门隙,缝隙；空隙；火花隙；间距,范围,区间,间隔；裂缝,裂口,缺口；放电器; 使产生裂缝,豁开 overlap : n. 重叠,重复;vt. 重叠,重复;vi. 迭盖 region : n. 区域,地方,地区,范围,区,领域,层 jigsaw : n. 竖锯;vt. 用竖锯锯 piece : n. 块,片,篇,碎片,部分;vt. 修补,修理,结合;vi. 接头 identical : a. 同一的,恒等的,完全相同的 primarily : ad. 主要地,首先地,基本地 polygon : n. 多角形,多边形 straight : n. 直线,直;a. 直的,笔直的,正直的,直接的,整齐的,连续的;ad. 直接地,立即,不断地 convex : a. 中凸的,凸圆的,凸面的;n. 凸状,凸面体,凸透镜 entirely : ad. 完全,全然,一概 properties : 道具 establish : vt. 建立,确立,制定;vi. 移植生长 obvious : a. 明显的,明白的,显然的 demonstrate : vt. 示范,证明;vi. 示威 equilateral : n. 等边形;a. 等边的 clear-cut : a. 轮廓清晰的,明白的,清楚的 hexagon : n. 六角形,六边形 ancient : a. 远古的,旧的 exploit : n. 功绩,勋绩;vt. 开发,利用,开拓,剥削 honeybee : n. 蜜蜂 honeycomb : n. 蜂巢,蜂房,蜂窝;a. 蜂巢的;vt. 开多孔使成蜂巢状;vi. 满是洞孔 quadrilateral : a. 四边形,四边地,四角地 devoid : a. 全无的,缺乏的 uncovered : a. 无遮盖的,未戴帽子的,未保险的 |
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地板
发表于: 2008-12-10 13:10
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