Digital sand timer with artistic design. Time flows and does it stylishly. This digitized hourglass can be used to time anything for up to 60 minutes. It's like having a nice looking visual indicator of how much time is left on your task.* KIDS FRIENDLYTimer visualizes time to kids and lets them feel the time. Without reading or even knowing the numbers one can look at the visualized time flow, feel it and understand how long to wait or whether to hurry up.* STAY NOTIFIEDIt lets you set the alarm sound that will play when the timer is finished. You can choose from 16 unique alarm sounds, melodies and loops. You’ll be notified when your time is up even if you’re using another app or your device is locked. It can also repeat the sound alarm (up to 3 times) at the given interval if it was missed/snoozed.* COLOR YOUR TIMEYou can easily change the timer color to fit your personal lifestyle. There are 5 color themes: turquoise, red, green, amber and pink. Just pick the one you like in the application settings.* UNIVERSAL APPTimer works both on your iPhone/iPod and iPad, contains HD graphics for retina and iPad displays and supports all screen orientations for all devices. [+Retina graphics for iPad 3rd generation]* SEE ALSO: Best TimerBeautifully designed sand timer, stylish kitchen timer, countdown/up and powerful stopwatch All in one creatively combined Best Timer application to suit all your timing needs. Search "Best Timer" on iTunes (http://itunes.apple.com/app/best-timer/id415656570) 洪琮欽 時間倒數 Digital sand timer with artistic design. Time flows and does it stylishly. This digitized hourglass can be used to time anything for up to 60 minutes. It's like having a nice looking visual indicator of how much time is left on your task.* KIDS FRIENDLYTimer visualizes time to kids and lets them feel the time. Without reading or even knowing the numbers one can look at the visualized time flow, feel it and understand how long to wait or whether to hurry up.* STAY NOTIFIEDIt lets you set the alarm sound that will play when the timer is finished. You can choose from 16 unique alarm sounds, melodies and loops. You’ll be notified when your time is up even if you’re using another app or your device is locked. It can also repeat the sound alarm (up to 3 times) at the given interval if it was missed/snoozed.* COLOR YOUR TIMEYou can easily change the timer color to fit your personal lifestyle. There are 5 color themes: turquoise, red, green, amber and pink. Just pick the one you like in the application settings.* UNIVERSAL APPTimer works both on your iPhone/iPod and iPad, contains HD graphics for retina and iPad displays and supports all screen orientations for all devices. [+Retina graphics for iPad 3rd generation]* SEE ALSO: Best TimerBeautifully designed sand timer, stylish kitchen timer, countdown/up and powerful stopwatch All in one creatively combined Best Timer application to suit all your timing needs. Search "Best Timer" on iTunes (http://itunes.apple.com/app/best-timer/id415656570)

李比希發現維勒寄給他的根本不是無機物氰酸銨，而是名為「尿素」的有機物！難道沒有生命力的無機物也有可能合出有機物嗎？或是生命力什麼的根本不存在？讓我們繼續來看看維勒的跨界大實驗！

當時的科學家認為物質分為有機物與無機物，兩者差別在生命力的有無，而且兩者間是無法互相合成的。做無機化學的維勒在貝才利烏斯博士指導下，發表了氰酸銨研究，會後遇到研究有機化學的李比希，跟維勒要了一些氰酸銨，李比希有什麼企圖呢？

馬德堡市長發現原本被靜電吸引的羽毛，在接觸了帶電物體不久後居然會排斥，這個奇怪的現象，讓杜菲與格雷激起了研究靜電的慾望，格雷也在實驗中發現，原來靜電是可以傳遞的。

牛頓透過微積分整合了伽利略與笛卡兒的想法，成為「力學奠定者」，正當牛頓沾沾自喜之時，卻被一個簡單的碰撞問題給卡住了！

電解和陰離子、陽離子與陰極、陽極是什麼？電解是指化合物加到水中之後，電經過化合物水溶液之後，會把化合物分解的過程。陰、陽極是指電極的性質不同，法拉第認為電進入水中的電極稱為陽極，而電離開水的電極稱為陰極。陰、陽離子是指當可以被電解的化合物，在水中會變成帶電的離子狀態。而根據它們所帶的電和性質不同，分成會被陽極吸引的陰離子 ( 帶負電 )，以及被陰極吸引的陽離子 ( 帶正電 ) 兩種離子。

古希臘人認為人看得見東西因為眼睛有內火。學者阿基米德嘗試集結村人眼中的內火對抗羅馬戰船，卻沒有成功。阿基米德回家找辦法，竟找到歐基里德「光學」這本書！阿基米德研究光學後，發現太陽亦會發出火元素。而發出的火元素具有直線前進和反彈的特性，阿基米德要如何運用它對抗羅馬大軍呢？

中世紀的歐洲人普遍認為，電與磁是一樣的，而當時的英國御醫吉爾伯特，針對這件事情提出質疑，並向當時最博學的義大利學者波爾塔展開了一場對決。

顏色世界的奧秘：物體如何呈現色彩？世界上會有各種顏色，是因為白光中包含了多種顏色的光線，而不同物體會選擇性地反射或透射特定顏色的光。這些被反射或透射的光進入我們的眼睛後，就形成了我們所看到的顏色。當白光照射在透明或半透明的物體上（像色片、玻璃），它們的顏色是由「選擇性透射」產生的。這些物體會只讓某些顏色的光通過（透射），吸收其餘的顏色，我們看到的，就是被透射出來的那個顏色。例如：紅色半透明色片會吸收綠光和藍光，只讓紅光通過，所以看起來是紅色的。因此，無論是反射光或透射光，都是因為不同物質對光的選擇性處理，加上我們眼睛對色光的感知能力，才讓這個世界呈現出五彩繽紛的樣貌。

熱傳導是什麼？熱會從溫度較高的地方，傳遞到溫度較低的地方。而熱透過不同溫度物體直接接觸，從高溫處傳到低溫處的方式，稱為熱傳導。傳導是固態物質的主要傳熱方式，不同材質傳遞熱的能力不同，熱傳導效果的比較如下：介質狀態：固態 > 液態 > 氣態材質：金屬 > 非金屬其中，金屬的熱傳導能力大多比非金屬好，因此我們常用金屬製作鍋子、水壺等需要快速導熱的用品。舉例來說，若將兩支分別為金屬與木頭的湯匙插入同樣溫度的熱水中，過一段時間後會發現金屬湯匙的另一端會變熱，而木頭湯匙的另一端幾乎沒感覺，這正是因為金屬熱傳導能力好、木頭熱傳導能力較差的結果。