【核融合究竟快好了沒】
#ITER最新進度 #史上最大拼裝車
▋前行提要
核融合反應指兩個較輕的核種克服彼此之間的庫侖斥力、靠得足夠接近並融合成一顆新核種的過程。融合過程所損失的質量將轉換為龐大的能量(E=MC^2)。氘-氚核融合反應是核融合發電的最佳燃料，其無出其右的能量密度是極為理想的能量來源。數十年來，無數的研究人員和工程師都在探究如何駕馭這股能量。說說能源也曾經介紹過
https://reurl.cc/X69MG0

然而，要在地表上重現太陽內部的反應並非易事。地表上無法產生如太陽般的重力，科學家於是設計了一種能同時裝載燃料、外加強力磁場和升溫的裝置。這就是托卡馬克(Tokamak)，俄語"具有磁線圈的環形裝置"的縮寫。托卡馬克形狀從黎明期的甜甜圈設計，演變成蘋果般的環狀設計或是扭結型甜甜圈。前者代表是國際熱核融合實驗反應爐(International Thermonuclear Experimental Reactor, ITER)，後者代表是德國的Wendelstein 7-X 仿星器(Stellarator)。

一個托卡馬克通常包含以下重要系統組件：真空容器(Vacuum Vessel)、容器內壁護甲(Blanket)、偏濾器(Divertor)、超導磁鐵(Magnets)、低溫恆溫器(Cryostat)和偵測器(Diagnostics)。磁拘束設計會確保氣態燃料激發至電漿態(俗稱點燃(ignition))時漂浮在容器內而不會物理性接觸到容器內壁。而如何以最小能量點燃、維持電漿形狀、輸出能量最大化，則是電漿物理研究的核心議題。儘管高溫電漿的輸出能量已經能大於點燃電漿的所需能量(輸入能量)，但達到實用化階段(輸出能量/輸入能量比例>=10)、且維持足夠長的時間仍是一個瓶頸。這個瓶頸即將由ITER突破。

ITER是個在國際核融合研究協議底下的巨型工程，建成後將會是世界上最大的磁約束電漿物理學實驗爐，爐子位於法國南部的卡達拉舍(Cadarache)附近。ITER的另一個工程目標是驗證大規模發電(無庸置疑的無碳排乾淨能源)的可行性。ITER預計製造超過攝氏10億度的氫電漿體，達成「輸出能量/輸入能量比例>=10」並產出約500 MW的核融合能量。

ITER將向世人證實核融合發電是個務實可行且非常安全的發電裝置，也會替未來世上的核融合電廠製造氚燃料。

▋ITER目前進度
2020年5月25日到27日三日間，約200名的工程團隊安裝了首個低溫恆溫器底座(cryostat base)(如附圖"The bottom cryostat")組件。這個低溫恆溫器底座--整個托卡馬克中單一最大也最重的組件--是底層構造的巨型金屬筒，將會承載反應爐其餘的零組件、諸如真空容器、巨型超導磁鐵和低溫恆溫系統，可說是ITER爐子的蓮花座。團隊會接著安裝低溫恆溫器的底部圓筒、來自南韓的真空容器組件、來自日本的環面磁線圈(toroidal field coils)和熱遮罩。建設團隊正戮力於讓主要組件於2021年底全數到位，以趕上2025年年底的完工期限。

然而就在2019年，COVID-19來襲。由於建造過程中、零組件必須在正確的時間送達施工現場，若強制中止將使佈及全球且數以百計的供應商和供應鏈分崩離析；故高層決定維持原建設步調，同時實施了一系列措施: 保持社交距離、洗手、戴口罩等。也讓約2000名白領員工改為遠端工作、現場員工數則從2500降為700名。

儘管如此，歐盟的真空容器組件的運送還是遭受了影響。機構長Bigot表示，目前每天最低開銷是一百萬歐元；他將於下個月和ITER委員會進行遠端視訊會議時就疫情相關事宜進行討論。屆時，他希望委員會會決定：追加預算以維持現步調，或是追加少一點的預算並展延一年。

▋技術困境
高能中子轟擊材料會導致材料劣化，這個特殊現象稱為輻射損傷。若輕水爐(沸水式)運行40年所產生的傷害是1,則商用核融合爐在整個服役週期內所產生的傷害將會是100左右。能抗輻射損傷、具低放射性、便宜又耐用的材料會是下一階段--DEMOnstration Power Station(DEMO,商用示範爐)--的主要挑戰。

ITER里程碑，來自於各個成員國家二三十年來的長期政策支持和各國科研人員的努力工作，ITER的所有技術果實自然也將由成員國間分享。儘管ITER計畫非我國國力能及，但是否該藉此反思一下，我國能源產業和科學研究是否存在任何十年期以上、且確切執行的長期政策呢？ 還是每四年畫個大餅後無疾而終呢？

▋參考資料
ITER官網
https://www.iter.org
Science 訪談報導主要聚焦近期COVID19影響
https://reurl.cc/oLq2RM

————————————————————

下文為上方引用Science Insider訪談ITER計畫的報導翻譯節錄

▋疫情中的ITER
過去兩天，約200名的團隊小心翼翼地吊起冷卻基座(cryostat base)--相當於棒球內野大小、重如巨型檜木的大型鋼鐵圓盤--並放入托卡馬克底座。這個冷卻基座--整個托卡馬克中單一最大也最重的組件--是底層構造的巨型金屬環，將會承載反應爐其餘的零組件、諸如真空容器、巨型超導磁鐵和冷卻系統。建設團隊正戮力於讓主要組件於2021年底全數到位，以趕上2025年年底的完工期限。

ITER有好長一段時間僅止於人們心中的概念設計。ITER最初於80年代被提起，後於2007年在法國正式變成跨國計畫。參與成員包括中國、歐盟、印度、日本、南韓、俄羅斯及美國。該計畫原定於2016年完工，但時程表在2016年時由新任機構長官General Bernard Bigot延後至2025年末(並追加了預算)。

然而在2019年建設進度接近70%時，COVID-19瘟疫來襲。由於建造過程涉及佈及全球且數以百計的供應商；後者被要求將零組件在正確的時間送達施工現場，若強制中止後再開將讓一切分崩離析。是故，和世界其他角落的科研設施不同，上層決定維持原建設步調，約2000名白領員工改為在家遠端工作，而現場員工則從2500降為700名。

[French pastries / 法式甜點] ＃咕咕霍夫 / ＃Kouglof (for English, click “see more”.)

決定去 Colmar 之後，除了訂下拜訪 Christine Ferber 的甜點店、在老城區漫遊，感受小鎮魅力外，想到能夠在當地品嚐到亞爾薩斯特色甜點 —— Kouglof（咕咕霍夫），也讓我興奮不已。

Kouglof 是一款重奶油麵包，由布里歐許麵糰（pâte à brioche）加上用蘭姆酒或櫻桃白蘭地浸漬的葡萄乾製成、還會加上杏仁片。外型有旋轉條紋、內裡中空就是它的特色。在亞爾薩斯，kouglof 是在陶製的模具中烘烤而成。顏色鮮豔、造型可愛、有時外面還有各種裝飾紋樣的模具非常引人注目，是許多人去亞爾薩斯會選購的紀念品。

關於 kouglof 的起源有很多傳說，有一說是由瑪麗安東尼皇后從奧地利帶入法國，更知名的則是東方三賢士在前往伯利恆為耶穌祝壽的途中經過亞爾薩斯的小鎮 Ribeauvillé，為了回報為他們提供落腳處的當地糕點師 Kugel（一說是陶匠），而製作了這個甜點，形狀和賢者們的頭巾相同。而那位愛好美食的前波蘭國王 Stanisław Leszczyński 在法國洛林地區落腳後，發現當地的 kouglof 太乾，而命人將浸在 Malaga 酒中，最後發明了 baba（巴巴）。不論傳說何者為真，kouglof 早在 18 世紀便已經出現在亞爾薩斯，而且深受當地人喜愛。

由於起緣於德法邊境的亞爾薩斯，kouglof 有很多種拼寫法，其中一個德文的拼法是「kugelhopf」，kugel 在德文中是「球」之意，而「hopf」是啤酒花「hop」之意（也有一說其實是「hefe」酵母），而過去製作 kouglof 時，是以啤酒酵母將麵糰發酵。

我在 Colmar 時發現當地還有另外一種加了果乾與香料（多半是肉桂）的布里歐許麵包，稱為「langhopf」，是使用長型的麵包模製作。在 Colmar 當地看到的 langhopf 做法多半是烤好之後在外面裹上一層肉桂糖粉，看起來非常特別。可惜因為一個人實在吃不下那麼多麵包，只好留著下次再去品嚐了。

點照片看更多 kouglof 的種類和相關故事！

🔖 延伸閱讀：

和 kouglof 只有一步之遙的巴巴：https://tinyurl.com/yxqubgt5

Kouglof 的中歐親戚 babka：https://tinyurl.com/y3vyj9sq

果醬女王 Christine Ferber 隱藏在 Colmar 附近鄉間小鎮的甜點店：https://tinyurl.com/yypq6jlj

我讀《甜點教父河田勝彥的法國鄉土甜點之旅》：https://tinyurl.com/y6lk34la

*******

If you ask what have I tasted during my trip to Colmar, how could I miss kouglof, one of the most renowned and beloved Alsatian specialties?

Made of the brioche dough with raisins soaked in rum or kirch as well as almond flakes, kouglof is a pastry in between cakes and bread. The high, creased, toroidal pottery kouglof mould, often brightly-coloured and sometimes painted with beautiful motifs, is also a popular souvenir among tourists.

Lots of legends and stories are associated with the origin of kouglof. Some say that the Austrian queen Marie-Antoinette brought it to France while some of the narratives claim that when the Three Magi were on their way to Bethlehem, they made the cake to thank a local pâtissier (or a pottery maker) named Kugel for his hospitality, and the shape of the cake comes from the turban of the Magi. Stanisław Leszczyński, the gourmet Polish king also takes part in transforming this Alsatian delicacy into a great classic of French pastry. When he settled in Lorraine, he found that the local kouglofs were too dried that he asked his pastry chefs to soak the cake into Malaga wine to make it more pleasant to enjoy, and that is how baba is born. No matter what, kouglof has appeared in Alsace before 19th century and is very popular in the region of Alsace.

Many varieties exist with regard to the spelling of kouglof; one of which is "kugelhopf". Kugel means "ball" in german while "hopf" means "hop", indicating where the yeast used to rise the cake in from. Others claim that it could mean "hefe", yeast in German.

When I was in Colmar, I found "langhopf", another local variety of brioche made with dried fruits as well as spices, mostly cinnamon. It is baked in a creased rectangular pan and then coated with cinnamon and sugar. As I have only one stomach, I'll have to save it to my next visit.

Click on the photos and get to know more about kouglof!

🔖 You might also like:

Baba, a kouglof one leveled-up: https://tinyurl.com/yxqubgt5

Babka, a close cousin of kouglof in mid-Europe: https://tinyurl.com/y3vyj9sq

Maison Ferber, the candy house of Christine Ferber, queen of jams: https://tinyurl.com/yypq6jlj

La Belle Histoire de Gâteaux Provinceaux by Katsuhiko Kawada: https://tinyurl.com/y6lk34la

#yingspastryguide #alsace #colmar #paris

GRANDIOSO K1X

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(Source: Esoteric Japan)