吶喊為挪威畫家愛德華·孟克的作品,其呼喊的「怪異」樣貌形象非常鮮明。902Please respect copyright.PENANAt60e1J6iut902Please respect copyright.PENANAgKo33t2nPX
902Please respect copyright.PENANACiD5vI4Cyr
他本人在1893至1916年畫出多個版本,而其中一幅展示在孟克美術館(Munch Museum)的版本因多處黃色地方出現變白及脫落跡象關係(圖1的數字標記區域),自2006年起已甚少公開示人。902Please respect copyright.PENANASmv9DasqVK
902Please respect copyright.PENANAuV9d2kpcWa
作品現時正處於光線陰淡、攝氏18度、相對濕度約50%的環境備受保護。902Please respect copyright.PENANAuvrYMdsZeS
902Please respect copyright.PENANAuAsXTiqO3Y
902Please respect copyright.PENANAOdMAAU9qUc
(圖2)為了解箇中顏料變色及脫落的機制,有科學家對吶喊作品作出深入研究,並在近日發表文章講述得出的結果(Ref1)。902Please respect copyright.PENANACTXZIoCPQ4902Please respect copyright.PENANAGC3iy6hkce
902Please respect copyright.PENANAukhQAVQHNt
Cadmium sulfide,為該時期常用作為黃色顏料的化學物。902Please respect copyright.PENANAUjUgdhBigP
902Please respect copyright.PENANARVyVwiTmrw
同期的文森·梵谷 (Vincent van Gogh)、詹姆斯・恩索 (James Ensor)和亨利·馬諦斯(Henri Matisse)均有利用這種化學物所製成的顏料,而相關的作品亦有出現黃色顏料變白的現象。902Please respect copyright.PENANAGFry5in7EC
902Please respect copyright.PENANA75WJR8FzzI
該時期主要有兩種方式製作Cadmium sulfide,分別為Dry及Wet Method。902Please respect copyright.PENANAM7oFWcIx6W
902Please respect copyright.PENANAt4J8J2Fnab
Dry Method為以300°C至600°C及零氧氣的方式,加上大量硫元素(Sulphur)調配Cadmium sulfide的方式,得出的成品相對上較為純正。902Please respect copyright.PENANASeJoN8ZMLO
902Please respect copyright.PENANAKPrXuYZSX1
Wet Method為將不同的化學物混合在一起(如圖中所示),再以沉澱的方式獲取固體Cadmium sulfide。902Please respect copyright.PENANAvm59PHLu1G
基於當時技術相對上不太先進,最終的產品會含有較多雜質及副產品。902Please respect copyright.PENANA8g5cOmQmSM
902Please respect copyright.PENANAf3CzMuQQCs
(圖3)科學家在文中嘗試挖取微量的吶喊畫碎粒,再利用各種技術檢測畫中的化學物成份。902Please respect copyright.PENANA7S0MpAIfoC902Please respect copyright.PENANAqYDtMZxLlK
902Please respect copyright.PENANAI1GPwQqwyG
圖3中間的圖片,其紅點代表黃色顏料Cadmium sulfide的存在。902Please respect copyright.PENANAHLLtskoT9p
902Please respect copyright.PENANAdlj6rBgC2b
下方的圖片,其三種顏色的出現分別代表Wet Method的副產物。902Please respect copyright.PENANAq2PhdT4FP8
902Please respect copyright.PENANAdZUYIlPQZU
紅點:Cd(OH)Cl902Please respect copyright.PENANAFCKaflwkly
綠點:CdSO4902Please respect copyright.PENANA3jNu5t1WbK
藍點:CdCO3902Please respect copyright.PENANAK0OkC9MBmd
902Please respect copyright.PENANAkBjk7uCnOv
這三種副產物,在長久而來的知識中已被確認是顏料變色及脫落的兇手,與吶喊作品所出現的現象不謀而合。902Please respect copyright.PENANAuLqkngDLnl
902Please respect copyright.PENANAudIjIgUC0h
(圖4)為進一步了解顏料變色的現象,他們找來了吶喊畫同期帶有黃色顏料的作品(他們已7914數字命名樣本)。902Please respect copyright.PENANAhr65ZeaVpL902Please respect copyright.PENANAEOuXOUuFxg
902Please respect copyright.PENANAoSTPuUuNQv
拿取畫中碎片後,(圖4左方)他們同樣發現裡頭含有Wet Method的副產物(綠點)。902Please respect copyright.PENANAoOvLc6Rbpn
902Please respect copyright.PENANAVHTl3OwI5t
為了解環境因素對於顏料變色的影響,他們對另一塊畫碎用上90 日相對濕度≥ 95%,攝氏為40°C,無光環境來模仿歲月的摧殘。902Please respect copyright.PENANAnnmpc7Pswu
902Please respect copyright.PENANA4OJaPfAbmX
他們發現得到Wet Method的副產物Cd(OH)Cl(綠點)數量大增且集中在一起,其目測得到黃色顏料變白的現象發生。902Please respect copyright.PENANAM4klQBqd5j
902Please respect copyright.PENANAFYrFKWG4tu
然而,用上用上90 日相對濕度=45%,攝氏為30°C,300W光源直接照射的環境來模仿歲月摧殘的話,則沒有感測得到Wet Method副產物的產生和顏料變色現象發生。902Please respect copyright.PENANAqRvbxq4zMm
902Please respect copyright.PENANAOLWGjYTyRA
902Please respect copyright.PENANAfkzGxvchtM
(圖5)另外,他們亦對愛德華·孟克那時期捐贈予館舍的顏料油作出檢測。902Please respect copyright.PENANAtSKFRgdRWg902Please respect copyright.PENANADWfr2atFrI
902Please respect copyright.PENANAavpuCWKfho
在畫紙塗上顏料油後,已能測量得到有一定程度份量的Wet Method副產物Cd(OH)Cl(左圖綠點)。902Please respect copyright.PENANAPUVwYHuNim
902Please respect copyright.PENANAF5952jcC8H
(右圖)用上90 日相對濕度≥ 95%,攝氏為40°C的方式摧殘後,綠點數量大增且集中在一起。902Please respect copyright.PENANAUthmDve5kk
902Please respect copyright.PENANAkNs4zR7I73
902Please respect copyright.PENANA1DJorwY4a7
(圖6)換句話說,當時期以Wet Method製作的Cadmium sulfide顏料以及愛德華·孟克所使用的顏料油,乃是導致畫中黃色地方出現變白及有脫落跡象的元兇,而其變色的機制主要由相對濕度和溫度而非光線控制。902Please respect copyright.PENANAxGcNgLiIGN902Please respect copyright.PENANACEarjEoxiG
902Please respect copyright.PENANAFyGKZAW1TU
基於這發現,在相對濕度及溫度嚴密的控制下,吶喊他日將來也許會有機會可以再度長期公開示人。902Please respect copyright.PENANA7b2fGDgPiw
902Please respect copyright.PENANAlJ6CbPQEki
如果想我快啲出文的話,請入去Penana網站科普專欄–薯不揀單俾一個like以及Bookmark,這對我非常之重要。902Please respect copyright.PENANAMkpTbuyIpL
902Please respect copyright.PENANAaCYIyGoPGw
Link: https://www.penana.com/story/66244/%E7%A7%91%E6%99%AE%E5%B0%88%E6%AC%84-%E8%96%AF%E4%B8%8D%E6%8F%80%E5%96%AE/toc902Please respect copyright.PENANARUUmU2fV0H
902Please respect copyright.PENANAHr3olO6xsE
同時亦可以在Penana網站裡按「買一嚿/半嚿薯仔」,以課金的方式推動我繼續搜羅資料寫文,多謝。902Please respect copyright.PENANAqrvhB6nrGp
902Please respect copyright.PENANAmpTdebo077
Link:902Please respect copyright.PENANANHF0fDFVA3
https://www.penana.com/user/27349/%E8%96%AF%E4%BB%94%E8%81%9E%E8%8C%B1%E8%8E%89/portfolio902Please respect copyright.PENANAbnpgZZtWiJ
902Please respect copyright.PENANA2sJmIfyS9M
902Please respect copyright.PENANAfQqZxcuMCm
有興趣接收科學資訊的話,歡迎follow IG: potatopigtongue。902Please respect copyright.PENANAmP5DIAqy9L
902Please respect copyright.PENANAY1t12zIUra
Ref1:https://advances.sciencemag.org/content/6/20/eaay3514902Please respect copyright.PENANARMW79pobTK