呼和浩特祛眼袋大概需要多少钱百姓健康
时间:2018年12月10日 10:30:15

Airplanes stay in the air because of one simple fact:there is no net force on them.And with no net fore,an object at rest stays at rest,and an object in motion stays that way-even if it#39;s in midair 10 km above the earth#39;s surface.Now of course it#39;s not like there aren#39;t forces acting on the airplane;gravity pulls down on the plane itself plus all of the people and baggage inside,and every single air molecule that is shot through the engine or collides with the fuselage or wings pushes on the plane as well.飞机之所以能飞在空中是因为:它们所受合力为零,合力为零时,静止的物体保持静止状态,运动的物体保持亦保持原态,---即使这个物体处在距地面10km高空,也不例外,当然,合力为零不表示飞机不受力的作用,飞机自身以及乘客和行李的总量使其下坠,穿过发动机或者与机身,机翼碰撞的,空气颗粒也会圣飞机产生作用力。But if all of these forces are balanced-in particular,if the air molecules push the plane UP enough to counteract gravity-then the plane stays up.Getting air molecules to push the plane up is he crucial part of flying,and planes do this by making sure the undersides of the wings crash into more air molecules more violently.than the upper sides of the wings.但是如果所有的力是平衡的,---特别是,当空气颗粒对飞机的上推力足以抵消重力作用时,----飞机就能停留在空中了,使空气颗粒产生的推力足以撑飞机是飞行的关键,为此,与机翼表面相比,机翼底面与空气颗粒接触更多,碰撞也更猛烈。When a plane is parked on the ground,air molecules bounce off of the top and bottom of the wings in roughly equal amounts,or with ;equal pressure.;No lift.But in motion,the curved shape of the wings and their slightly inclined angle means that the bottoms smash into more air molecules that before and smash harder into those molecules,so the pressure on the bottom of the wing goes up.当一架飞机停于地面,与机翼上下两面相作用的空气颗数量大致相同,也可以说;压力相当;无上升力,但在起飞时,机翼的曲线形状和少许的倾斜角度,意味着,与静止时相比机翼底部会与更多空气颗粒相碰撞,碰撞程度也更剧烈,因此机翼底部所受压力也会增加。In addition,fewer air molecules now strike the top of the wing and those that do strike it less forcefully,partly because it#39;s being;shielded;by its own forward motion (the way running into the rain keeps your back drier).另外,此时撞击机翼顶部的空气颗粒较少,撞击力也较小,部分原因是飞机受到前进力的;保护;,(就跟冲进雨里时背后依然干燥是一个道理)。And partly because a curving stream of air has lower pressure on the inside of the curve since the molecules get thrown centripetally to the outside.But whatever the reasons,the pressure on the top of the wing goes down.So,low pressure on the top plus high pressure on the bottom,and the plane has lift.另一部分原因在于,弯曲流动的空气对曲线内侧的作用力较小,因为空气颗粒受向心力作用被甩开了,地论如何,机翼顶部的压力减小了,于是,由于顶部压力小而底部压力大,飞机受到上升力作用。And if the pressure/force imbalance is big enough,it can lift the plane up into the air against gravity!Now,all this crashing into air molecules to lift the plane also pushes to slow the plane down-which it would,if not for engines.Engines also push air,in this case,backwards either via a propellor,or a jet,or a jet driving a propellor.当作用力不平衡到一定程度,就可以无视重力托起飞机了,而这些托举起飞机的空气颗粒,也产生了阻碍飞机前进的力,好在发动机的推动力更大,发动机也在推动空气,对飞机而言,是向后推动,无论是螺旋桨发动机,或是喷气式发动机,或者喷气驱动螺旋桨。For various reasons,it turns out that you want to have a really big propellor driven by a really small jet for the most efficient engine.But even in inefficient engines,the spinning fan blades get their horizontal lift,which we call;thrust,;by moving quickly through air with a curved shape and a slightly inclined angle-they#39;re essentially mini-wings.由于种种原因,人们想要拥有,由极小的喷嘴产生极大推动力的,高效发动机,但是哪怕是低效的发动机,旋转的扇叶也会给飞机带来助力,我们称之为;推力;,它们以曲线形状和微妙的倾斜角,在空气中快速转动---相当于小翅膀。And so an airplane is essentially a meta-wing:it flies by moving mini-wings fast enough to push air molecules backwards,which moves the plane forward fast enough that its big wings push air molecules down.Whoa,Wingception.因此飞机本质上就像超级翅膀,它通过快速转动的小翅膀向后推动空气而飞行,极快的前进力给了大机翼,下压空气颗粒的动力,哇哦,翼度空间。 Article/201504/371195

You can stay healthy despite diabetes with these strategies for keeping your blood sugar controlled.遵循下面控制血糖的方法,即使患有糖尿病,也可以保持健康。You Will Need你需要A balanced meal plan平衡的餐饮计划Healthy foods健康的食品Regular eating habits规律的饮食习惯Carbohydrate and sugar contents碳水化合物和糖含量A doctor医生Exercise运动Relaxation techniques放松技巧Non-starchy vegetables (optional)不含淀粉的蔬菜(可选)Sugar-free drinks (optional)不含糖的饮料(可选)Steps步骤Never change your diet without first consulting your physician.要改变饮食习惯,一定要先向医生咨询。STEP 1 Eat healthy1.饮食健康Follow a healthy, balanced meal plan that includes carbohydrates, protein, and fat, as well as vitamins, minerals, and fiber.遵循健康平衡的饮食计划,包含碳水化合物,蛋白质,脂肪,以及维生素,矿物质和纤维在内。Fill up on non-starchy vegetables, such as greens, peppers, broccoli, and green beans.用不含淀粉的蔬菜来充饥,比如绿叶蔬菜,辣椒,西兰花和四季豆。STEP 2 Eat regularly2.饮食规律Don#39;t skip or delay meals. Keep your metabolism running strong and avoid overeating later by enjoying regular meals and snacks.每餐不要省略或延后。享用规律的餐饮和零食,保持有力的新陈代谢,避免稍后暴饮暴食。STEP 3 Count carbs3.计算碳水化合物Count carbohydrates to consistently control the amount of sugar in your bloodstream.计算碳水化合物,坚持控制血液中的糖含量。STEP 4 Don#39;t drink too much sugar4.不要喝太多含糖饮料Be mindful of the carbs and sugar present in drinks, such as regular sodas and juices, and limit your intake of these beverages.警惕饮料中的碳水化合物和糖,比如汽水和果汁,限制这些饮料的摄入量。Carry your own sugar-free drinks when you are away from home. Good choices are bottled water, club soda with lemon or lime slices, sugar-free soft drinks, and unsweetened or artificially sweetened tea.外出的时候自己携带不含糖的饮料。良好的选择包括瓶装水,加柠檬或青柠片的汽水,无糖软饮料,无糖或人工甜味剂的茶。STEP 5 Take your meds5.携带药物Make sure to take medication that your doctor prescribes as directed.一定要随身携带医生开的药物。STEP 6 Get your blood pumping6.锻炼Exercise regularly to keep your blood sugar down and maintain a healthy weight.经常运动,将血糖维持在较低水平,保持健康的体重。STEP 7 De-stress7.放松压力Use relaxation techniques, such as slow, deep breathing and progressive muscle relaxation, to reduce the level of sugar-elevating stress hormones in your blood.使用放松技巧,比如缓慢的深呼吸和渐进性肌肉放松技巧,降低血液中刺激血糖增加的压力荷尔蒙水平。Approximately 22 million people in the U.S., or 8 percent of the population, have diabetes.美国大约2200万人,也就是大约8%的人口患有糖尿病。 /201411/341220

I spend a lot of time thinking about the universe,我花了大量时间来思考宇宙but I never get bored.却从未感到过厌倦After all it#39;s a pretty extraordinary place.毕竟,这是一片非凡的领域This is the cosmos.这就是宇宙And a very large scale.浩瀚无际Each tiny point of light is an entire galaxy.每一个小光点都是一个完整的星系Each a cluster of as many as 400 billion individual stars.每一个星系都拥有多达四千亿颗恒星This view of the universe is only possible只有通过最新的超级计算机due to the latest super computers.才看得到这样的宇宙场景I find it indescribably beautiful.它是如此的星光灿烂Uncountable billions of galaxies forming a vast web数十亿无以计数的星系形成了一张巨网stretching away in all directions.向着四面八方延伸出去What#39;s more, I never get over the fact而且,有一个事实我从未忘怀that within this massive universe那就是,在这广袤无垠的宇宙中lies one perfectly ordinary spiral galaxy.存在着一个极其普通的螺旋星系Inside that galaxy exists a commonplace yellow star.在这个星系中存在着一颗平凡的金色恒星Orbited by eight planets.围绕着它的,是八颗行星On one of those planets lives a species在其中一颗行星上,生存着一个物种that is only just worked out what a remarkable place the universe is.他们刚刚了解到宇宙有多么奇妙Us.这就是我们,人类We#39;ve discovered more about the cosmos我们在上个世纪里对宇宙的探索发现in the last century than in all previous human history.达到了人类历史上前所未有的程度Finally we are solving the basic mysteries终于,我们开始着手破解那些that have perplexed our ancestors for at least 200,000 years.困惑祖先二十多万年的普遍神秘现象What I like above all is最吸引我的莫过于that the facts themselves are both breathtakingly elegant and surprising.事实本身是如此地惊险迷人而又出人意料We are living just as it donates us我们生存在宇宙赠予我们的环境中that the earth and everything around us was made by the stars.地球,以及我们身边的一切都源于恒星Boiling fantasies of hydrogen gas like our sun甚至是构成你睫毛的原子made even the atoms in your eyelashes.都源于同太阳一般,充满氢气的炽热球体We#39;ve worked out that the universe is almost unimaginably ancient.我们计算出宇宙的古老程度几乎无法想象About 14 billion years old.大约存在了140亿年And that it will continue to exist for at least twice that long.而宇宙也还会继续存在至少两个这么久But without a doubt,但无需怀疑the most remarkable fact of all is that the entire enormous universe,最美妙的事实莫过于整个广袤的宇宙all the innumerable galaxies所有无以计数的星系even time and space and the forces of nature themselves,甚至是时间空间,以及自然力量本身simply materialized out of nothing.都源于虚无,终成宇宙 Article/201508/393030

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