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《少年科学》2007,(10)
Butterflies Butterflies are insects with big wings.They have six legs and three main body parts.The three main body parts of a butterfly are the head,the thorax and the abdomen.Butterflies also have wings.They use their colourful wings to fly and to attract mates.Butterflies have 相似文献
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When buying a house, you must be sure to have it checked for termites (白蚁). A termite is much like an ant in its communal habits, although physically the two insects are different.Like those of ants, termite colonies(群 相似文献
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Audio Video coding Standard (AVS) is the latest audio and video coding standard of China. AVS Part 7 (also known as A VS-M) targets mobility applications where error concealment is of great importance. This paper first briefly introduces the general concept of error concealment. Then two error concealment schemes are proposed and implemented on AVS-M decoder under different test conditions. Simulation results of the schemes and suggestions on how to use these tools are also provided. 相似文献
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Insulin is one of the most extensively studied protein hormones, and its structure and function have been elucidated in many vertebrate species, ranging from human to fish. Insulin-like peptides (ILPs) also have been found and characterized in different invertebrates, including nematodes, mollusks and insects. However, insect ILPs turned out to be a structurally diverse group encoded by large multi-gene families that are expressed in the brain and other tissues and serve functions different from vertebrate insulin. Recent physiological and genetic studies have revealed that, in different insect species, the conserved insulin signaling pathway plays a key role in the regulation of a variety of fundamental processes, such as metabolism, growth, reproduction and aging. Here, the structures, distributions, conserved signaling pathways, and physiological functions of insect ILPs are reviewed in detail. 相似文献
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A Most people around the world are right-handed.This also seems to be true in history.In 1799,scientists studied works of art made at different times from 1500 B.C.to the 1950s.Most of the people shown in these works are right-handed,so the scientists 相似文献
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INTRODUCTION Epoxide hydrolases (EHs) play a key role in the transformation and metabolism of xenobiotics in bio-systems (Armstrong, 1987). The enzymes are found ubiquitously in various organisms, including mammals, plants, insects and microorganisms, etc. (Argiriadi et al., 1999). In the human body, EHs are found in organs such as the liver, lung, heart, brain, breast tissue, kidneys, and are associated with various diseases, including emphysema, pregnancy-induced hypertension, acute r… 相似文献
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《少年科学》2007,(Z1)
Bats are the only mammals that can fly.They are warm-blooded,furry animals that suckle their young.Bats are flying mammals,but they do not have feathers like birds.They have wings of skin that stretch from their fingers to their feet.Many bats eat insects which they hunt at night.These bats make sounds that bounce off objects.Bats use the echoes 相似文献
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If A and B are two sets,A is said to be a subsetof B if and only if every element of A is also anelement of B.The subset relation is indicated by thesymbolismAB(or BA)which is read“A is a subset of B”or“A is includedin B”or“B includes A”.It is clear from the definition that every set A isa subset of itself.It is important to know that theempty setis the subset of any set A:A.(Wewill explain it in the logic part)Two sets A and B are said to be equal if and 相似文献
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Most people around the world are right-handed.This also seems to be true in history.In 1799,scientists studied works of art made at different times from 1500 B.C.to the 1950s.Most of the people shown in these works are right-handed,so the scientists guessed that right-handedness has always been common through history. 相似文献
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As is known to all, Virginia Woolf's concern with feminist thematics are dominant in A Room Of One's Own (1929), however, her another short story —— "the Mark on the wall"also best presents us a woman's world at the beginning of 20th Century. 相似文献
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《少年科学》2007,(9)
What is an Insect Insects are small animals with six legs and three body parts. Insects have three main body parts.These three parts are the head, the thorax and the abdomen.All insects have two antennae.They use their antennae for touch,taste and smell.Insects don't have bones. They have a hard shell that protects their bodies.This hard shell is called exoskeleton. 相似文献
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A range of ferrocenyl sulfides are synthesized and screened. Among them 1-α-methysulphoferrocenyl ethyl acetate and 1-α-methysulphoferrocenyl alcohol are found to be unexpected catalysts, which is first reported mediating in sulfur ylide epoxidation reactions, furnishing a novel approach for highly stereoselective synthesis of oxiranes with 98%-100% trans-isomer. The protocol also has excellent yield, convenient workup and recycled starting material. The reason of high trars-selectivity is due to the bulky ferrocenyl sulfide group, which stabilizes the intermediates and determines the trans priority. A possible catalytic mechanism is also proposed. 相似文献
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A Doll’s House and Macbeth obviously belong to different categories in content. However, the two heroines in these two plays, Nora Helmer and Lady Macbeth, demonstrate similar feminist qualities. By staging an overall contrastive analysis on the personality and tragic life of two protagonists from the perspective of feminism, it is founded that both of them are victims oppressed by the patriarchal system and they all have feminine consciousness against this system. Nevertheless, their distinctive complex personalities and different story settings make the reasons for their rebellion differ in many ways and they end up with different endings. 相似文献
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Lions have been called the kings of the anim al world.These anim als can be found wild in Africa and India.Lions in A frica can go withoutwaterforup to one m onth,so they have no trouble during dry tim es. W ithout question,lions are also one of the m ost popularanim als to see in zoos.A lm ostevery zoo around the world has a few lions. It is very easy for people to tell m ale and fem ale lions apart.Lions are the only kind ofcatthatshow this strong difference between m ales and fem ales.A … 相似文献
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Part One Ⅰ.TEXT COMPREHENSION There are 20 statements in this part.Some of them are true(T),and some are false(F),according tothe texts you have learned.Write T or F in the following brackets.(20 points,1 point for each)1.After Rip Van Winkle had slept in the valley for anight,he found he had become a citizen of the United States.( )2.The Wrong House and New Applications are two stories With surprising endings.( )3.In Lady in the Dark,the old lady refused to give up her jewels because they told the past of her life.( )4.Helen Keller thought it would be a good thing for a small Child to be stricken blind and deaf for a few days.( ) 相似文献
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丁红艳 《语数外学习(初中版七年级)》2011,(11):44-46
A Hi,boys and girls.Have a look at Zig Zag’s Clothes Shop.We have black and blue hats for $15.The blue sweater is $33 and the red sweater is $30.The yellow shorts are also $30 and the green shorts are on sale for $25! 相似文献