英国基尔大学化学Assignment代写:单位和稀释

计算化学溶液的浓度是所有化学学生必须在他们的研究早期发展的基本技能。什么是注意力?浓度是指溶解在溶剂中的溶质的量。我们通常认为溶质是添加到溶剂中的固体(例如,将食盐添加到水中),但溶质可以很容易地存在于另一相中。例如,如果我们向水中加入少量乙醇,则乙醇是溶质,水是溶剂。如果我们在较大量的乙醇中加入少量水,那么水可能是溶质!一旦确定溶液中的溶质和溶剂,就可以确定其浓度。浓度可以用几种不同的方式表示,使用质量百分比组成,体积百分比,摩尔分数,摩尔浓度,摩尔浓度或当量浓度。在制备液体溶液时最常使用的体积百分比或体积/体积百分比。体积百分比定义为:v / v%= [(溶质体积)/(溶液体积)]×100%注意体积百分比是相对于溶液体积而不是溶剂体积。例如,葡萄酒约为12%v / v乙醇。这意味着每100毫升葡萄酒中含有12毫升乙醇。重要的是要实现液体和气体体积不一定是添加剂。如果你混合12毫升乙醇和100毫升葡萄酒,你会得到少于112毫升的溶液。作为另一个例子,可以通过取700ml异丙醇并加入足够的水以获得1000ml溶液(其不是300ml)来制备70%v / v摩擦醇。 英国基尔大学化学Assignment代写:单位和稀释 Calculating the concentration of a chemical solution is a basic skill all students of chemistry must develop early in their studies. What is concentration? Concentration refers to the amount of solute that is dissolved in a solvent. We normally think of a solute as a solid that is added to a solvent (e.g., adding table salt to water), but the solute could just as easily exist in another phase. For example, if we add a small amount of ethanol to water, then the ethanol is the solute and the water is the solvent. If we add a smaller amount of water to a larger amount of ethanol, then the water could be the solute! Once you have identified the solute and solvent in a solution, you are ready to determine its concentration. Concentration may be expressed several different ways, using percent composition by mass, volume percent, mole fraction, molarity, molality, or normality. Volume...
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英国赫瑞瓦特大学化学Essay代写:元素99或Es

Einsteinium最初是在1952年第一次氢弹爆炸,常春藤迈克核试验的后果中发现的。 加州大学伯克利分校的Albert Ghiorso和他的团队与Los Alamos和Argonne国家实验室一起检测并合成了Es-252,它具有6.6 MeV能量的特征α衰变。 美国团队开玩笑地将元素99命名为“pandamonium”,因为常春藤迈克测试代号为Project Panda,但他们正式提出的名称是“einsteinium”,元素符号为E. IUPAC批准了这个名称,但是符号为Es。 美国团队与斯德哥尔摩诺贝尔物理研究所的瑞典团队竞争,发现99和100元素并将其命名。 常春藤迈克测试已被分类。 美国团队于1954年公布了结果,测试结果于1955年解密。瑞典团队于1953年和1954年公布了结果。 英国赫瑞瓦特大学化学Essay代写:元素99或Es Einsteinium was first identified in the fallout from the first hydrogen bomb explosion in 1952, the Ivy Mike nuclear test. Albert Ghiorso and his team at the University of California at Berkeley, together with Los Alamos and Argonne National Laboratories, detected and later synthesized Es-252, which exhibits a characteristic alpha decay with an energy of 6.6 MeV. The American team jokingly named element 99 "pandamonium" because the Ivy Mike test had been codenamed Project Panda, but the name they officially proposed was " einsteinium", with element symbol E. The IUPAC approved the name but went with the symbol Es. The American team competed with a Swedish team at the Nobel Institute for Physics in Stockholm for credit discovering elements 99 and 100 and naming them. The Ivy Mike test had been classified. The American team published results in 1954, with the test results declassified in 1955. The Swedish team published...
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英国伦敦国王学院Assignment代写:X射线定义和属性

X射线或X射线是电磁波谱的一部分,波长比可见光波长(频率高)。 X射线波长范围为0.01至10纳米,或频率范围为3×1016Hz至3×1019Hz。这使得X射线波长介于紫外光和伽马射线之间。 X射线和伽马射线之间的区别可以基于波长或基于辐射源。有时x射线被认为是电子发射的辐射,而伽马射线是由原子核发射的。德国科学家WilhelmRöntgen是第一个研究X射线的人(1895年),尽管他不是第一个观察X射线的人。观察到的X射线是从大约1875年发明的克鲁克斯管发出的。伦琴称光“X射线”表明它是以前未知的类型。有时,辐射被称为Röntgen或伦琴辐射,仅次于科学家。接受的拼写包括X射线,X射线,X射线和X射线(和辐射)。术语x射线还用于指代使用x射线形成的射线照相图像以及用于产生图像的方法。 英国伦敦国王学院Assignment代写:X射线定义和属性 X-rays or x-radiation are part of the electromagnetic spectrum with shorter wavelengths (higher frequency) than visible light. X-radiation wavelength ranges from 0.01 to 10 nanometers, or frequencies from 3×1016 Hz to 3×1019 Hz. This puts the x-ray wavelength between ultraviolet light and gamma rays. The distinction between x-ray and gamma rays may be based on wavelength or on radiation source. Sometimes x-radiation is considered to be radiation emitted by electrons, while gamma radiation is emitted by the atomic nucleus. German scientist Wilhelm Röntgen was the first to study x-rays (1895), although he was not the first person to observe them. X-rays had been observed emanating from Crookes tubes, which were invented circa 1875. Röntgen called the light "X-radiation" to indicate it was a previously unknown type. Sometimes the radiation is called Röntgen or Roentgen radiation, after the scientist. Accepted spellings include x rays, x-rays, xrays, and X rays (and radiation). The term x-ray is also used to refer...
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英国埃塞克斯大学Essay代写:有机硅

有机硅是一种合成聚合物,一种由较小的重复化学单元制成的材料,称为单体,以长链结合在一起。有机硅由硅 - 氧主链组成,“侧链”由与硅原子连接的氢和/或烃基组成。由于其主链不含碳,因此有机硅被认为是无机聚合物,其不同于许多有机聚合物,其主链由碳制成。硅氧烷主链中的硅 - 氧键是高度稳定的,比许多其他聚合物中存在的碳 - 碳键更强地结合在一起。因此,与常规的有机聚合物相比,硅氧烷更耐热。有机硅的侧链使聚合物具有疏水性,使其可用于可能需要排斥水的应用。侧链(通常由甲基组成)也使硅氧烷难以与其他化学物质反应并防止其粘附到许多表面上。可以通过改变附着在硅氧主链上的化学基团来调节这些性质。 英国埃塞克斯大学Essay代写:有机硅 Silicones are a type of synthetic polymer, a material made of smaller, repeating chemical units called monomers that are bonded together in long chains. Silicone consists of a silicon-oxygen backbone, with “sidechains” consisting of hydrogen and/or hydrocarbon groups attached to the silicon atoms. Because its backbone does not contain carbon, silicone is considered an inorganic polymer, which differs from the many organic polymers whose backbones are made of carbon. The silicon-oxygen bonds in the silicone backbone are highly stable, binding together more strongly than the carbon-carbon bonds present in many other polymers. Thus, silicone tends to be more resistant to heat than conventional, organic polymers. Silicone’s sidechains render the polymer hydrophobic, making it useful for applications that may require repelling water. The sidechains, which most commonly consist of methyl groups, also make it difficult for silicone to react with other chemicals and prevents it from sticking to many surfaces. These properties can be tuned...
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英国伯明翰大学Essay代写:什么是晶体管?

要了解晶体管的工作原理,您必须了解半导体如何对电位做出反应。一些半导体将是n型或负极,这意味着材料中的自由电子从负电极(例如,它所连接的电池)向正电极漂移。其他半导体将是p型,在这种情况下,电子填充原子电子壳中的“空穴”,这意味着它表现得好像正粒子从正电极移动到负电极。该类型由特定半导体材料的原子结构决定。现在,考虑一个npn晶体管。晶体管的每一端是n型半导体材料,并且它们之间是p型半导体材料。如果您将这样的设备插入电池,您将看到晶体管是如何工作的:连接到电池负极端的n型区域有助于将电子推进到中间的p型区域。连接到电池正极端的n型区域有助于减缓从p型区域出来的电子。中心的p型区域都有。通过改变每个区域的电位,您可以极大地影响晶体管上电子流的速率。 英国伯明翰大学Essay代写:什么是晶体管? To understand how a transistor works, you have to understand how semiconductors react to an electric potential. Some semiconductors will be n-type, or negative, which means that free electrons in the material drift from a negative electrode (of, say, a battery it's connected to) toward the positive. Other semiconductors will be p-type, in which case the electrons fill "holes" in the atomic electron shells, meaning that it behaves as if a positive particle is moving from the positive electrode to the negative electrode. The type is determined by the atomic structure of the specific semiconductor material.Now, consider an npn transistor. Each end of the transistor is an n-type semiconductor material and between them is a p-type semiconductor material. If you picture such a device plugged into a battery, you'll see how the transistor works: the n-type region attached to the negative end of the battery helps propel electrons into the middle p-type region. the n-type region attached to the positive...
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英国巴斯大学Assignment代写:古希腊物理学史

众所周知,古人对他们的天文学最为有利,因为天文学在今天继续影响着我们。他们经常观察天空,这被认为是地球中心的神圣境界。对于每个人来说,太阳,月亮和星星以规则的方式在天堂中移动是显而易见的,并且不清楚是否有任何有文献记载的古代世界思想家都在质疑这种地心说。无论如何,人类开始在天空中识别星座,并使用黄道十二宫的这些星座来定义日历和季节。数学在中东地区首先发展起来,但确切的起源取决于历史学家所采用的方式。几乎可以肯定的是,数学的起源是用于商业和政府的简单记录保存。埃及在基本几何学的发展方面取得了长足的进步,因为需要在尼罗河年度洪水之后明确界定农业领土。几何学很快就在天文学中找到了应用。 英国巴斯大学Assignment代写:古希腊物理学史 The ancients are known perhaps best for their astronomy, which continues to influence us heavily today. They regularly observed the heavens, which were believed to be a divine realm with the Earth at its center. It was certainly obvious to everyone that the sun, moon, and stars moved across the heaven in a regular pattern, and it's unclear whether any documented thinker of the ancient world thought to question this geocentric viewpoint. Regardless, humans began identifying constellations in the heavens and used these signs of the Zodiac to define calendars and seasons. Mathematics developed first in the Middle East, though the precise origins vary depending upon which historian one talks to. It is almost certain that the origin of mathematics was for simple recordkeeping in commerce and government. Egypt made profound progress in the development of basic geometry, because of the need to clearly define farming territory following the annual flooding of the Nile. Geometry quickly found applications in astronomy,...
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英国利兹大学物理学Essay代写:土耳其物理

如上所述,问题的一部分是火鸡中的明暗肉的不同性质导致达到肌肉蛋白凝固的不同速率。如果你煮得太久,胸肉就凝固了;如果你不长时间煮这种鸟,黑肉仍然坚韧和耐嚼。食品科学作家Harold McGee表示乳房的温度为155-160华氏度(与Roger Highfield指出的整体温度一致),但你想要腿部180度或以上(Highfield没有解决的区别) 。由于你最终希望乳房和腿部温度不同,问题是如何成功实现这一目标。 McGree提出了一种选择,通过使用冰袋来保持鸟的乳房在解冻时比腿部低约20度,这样当它们被放入烤箱时,腿会在烹饪过程中获得“热启动”。 Food Network的Good Eats的Alton Brown曾提出另一种方法来建立不同的加热速率,使用铝箔将热量从乳房反射回来,从而导致腿部加热比乳房更快。他目前在Food Network网站上的烤火鸡食谱不包括这一步,但如果您观看相关视频,则会显示使用铝箔所涉及的步骤。 英国利兹大学物理学Essay代写:土耳其物理 Part of the problem, as described above, is that the different nature of the light and dark meat in a turkey result in different rates to reach the coagulation of the muscle proteins. If you cook it too long, the breast meat has coagulated; if you don't cook the bird long enough, the dark meat is still tough and chewy. Harold McGee, a food science writer, indicates aiming for 155–160 degrees Fahrenheit in the breast (which concurs with the overall temperature indicated by Roger Highfield), but you want 180 degrees or above in the leg (a distinction Highfield does not address). Since you ultimately want the breast and legs to be different temperatures, the question is how to successfully accomplish this. McGree presents one option, by using ice packs to keep the breast of the bird about 20 degrees lower than the legs while thawing, so that the legs get a...
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英国兰卡斯特大学物理学Essay代写:多普勒雷达如何工作?

一种以多种方式使用的发现是多普勒效应,尽管乍一看科学发现似乎相当不切实际。 多普勒效应完全是关于波浪,产生这些波的东西(源),以及接收这些波的东西(观察者)。 它基本上说如果源和观察者相对于彼此移动,那么它们中的两个波的频率将是不同的。 这意味着它是一种科学相对论。 实际上,这个想法已经被用于实际结果的两个主要领域,并且最终都得到了“多普勒雷达”的处理。 从技术上讲,多普勒雷达是警察“雷达枪”用来确定机动车速度的方法。 另一种形式是脉冲多普勒雷达,用于跟踪天气降雨的速度,通常,人们知道在天气报告期间使用的术语。 英国兰卡斯特大学物理学Essay代写:多普勒雷达如何工作? One discovery that is used in a variety of ways is the Doppler effect, even though at first glance the scientific discovery would seem to be rather impractical. The Doppler effect is all about waves, the things that produce those waves (sources), and the things that receive those waves (observers). It basically says that if the source and observer are moving relative to each other, then the frequency of the wave will be different for the two of them. This means that it's a form of scientific relativity. There are actually two main areas where this idea has been leveraged into a practical outcome, and both have ended up with the handle of "Doppler radar." Technically, Doppler radar is what is used by police officer "radar guns" to determine the speed of a motor vehicle. Another form is the Pulse-Doppler radar which is used to track the speed of weather precipitation, and usually, people...
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英国利物浦大学Essay代写:让保罗萨特的故事

“墙”的叙述者,Pablo Ibbieta,是国际旅的成员,来自其他国家的志同道合的志愿者,他们前往西班牙帮助那些为了保护西班牙作为共和国而与法国的法西斯主义者作斗争的人。与汤姆和胡安一起,他被佛朗哥的士兵俘虏了。汤姆像巴勃罗一样积极参与斗争;但胡安只是一个年轻人,碰巧是活跃的无政府主义者的兄弟。在第一个场景中,他们以非常简洁的方式进行了采访。虽然他们的审讯人员似乎写下了很多关于他们的信息,但他们几乎一无所知。巴布洛被问及他是否知道当地无政府主义领导人拉蒙格里斯的下落。他说他没有。然后他们被带到一个牢房。晚上8点,一名官员过来告诉他们,他们已经被判处死刑并将于次日早晨被枪杀。当然,他们因即将死亡的知识而度过了压抑的夜晚。胡安因自怜而堕落。一位比利时医生让他们公司让他们的最后时刻变得“不那么困难。”巴勃罗和汤姆努力接受在智力水平上死亡的想法,而他们的身体背叛了他们自然害怕的恐惧。巴勃罗发现自己汗流x背;汤姆无法控制他的膀胱 英国利物浦大学Essay代写:让保罗萨特的故事 The narrator of "The Wall", Pablo Ibbieta, is a member of the International Brigade, progressive-minded volunteers from other countries who went to Spain to help those who were fighting against Franco’s fascists in an effort to preserve Spain as a republic. Along with two others, Tom and Juan, he has been captured by Franco’s soldiers. Tom is active in the struggle, like Pablo; but Juan is just a young man who happens to be the brother of an active anarchist. In the first scene, they are interviewed in a very summary fashion. They are asked virtually nothing, although their interrogators seem to write down a great deal about them. Pablo is asked if he knows the whereabouts of Ramon Gris, a local anarchist leader. He says he does not. They're then taken to a cell. At 8:00 in the evening an officer comes by to tell them, in a perfectly matter of fact manner, that they've been sentenced to...
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英国曼彻斯特大学Essay代写:Simone de Beauvoir

西蒙娜·德·波伏娃于1967年发表了她的短篇小说“女人被毁”。与许多存在主义文学一样,它是以第一人称写成的,故事由莫妮克撰写的一系列日记条目组成,莫妮克是一位中年妇女,她的丈夫是一个勤奋的医生,他的两个长大的女儿不再住在家里。在故事的开头,她刚刚看到她的丈夫去了罗马,他在那里开了一个会议。她计划悠闲地开车回家,享受随意做任何她想做的事情,不受家庭义务的限制。 “我想为自己生活一点点,”她说,经过这么久。“然而,当她听到帽子Colette时,她的一个女儿患了流感,她缩短了她的假期,所以她可以在她的床边这是第一个迹象表明,在花了这么多年致力于其他人后,她会发现她新发现的自由很难享受。回到家里,她发现她的公寓非常空虚,而不是享受她的自由,她只是感到孤独。一天或者所以后来她发现她的丈夫莫里斯一直与诺埃莉有染,这是一个和他一起工作的女人。她很沮丧。 英国曼彻斯特大学Essay代写:Simone de Beauvoir Simone de Beauvoir published her short story, "The Woman Destroyed," in 1967. Like much existentialist literature, it is written in the first person, the story consisting of a series of diary entries written by Monique, a middle-aged woman whose husband is a hard-working doctor and whose two grown up daughters no longer live at home. At the beginning of the story she has just seen her husband off on a flight to Rome where he has a conference. She plans a leisurely drive home and relishes the prospect of being free to do whatever she wants, unconstrained by any family obligations. "I want to live for myself a little," she says, after all this time." However, as soon as she hears hat Colette, one of her daughters has the flu, she cuts her vacation short so she can be by her bedside. This is the first indication that after spending so many years devoted to others she...
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