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。961Please respect copyright.PENANALUz1z8JcGe961Please respect copyright.PENANAikGJQaZ8Ig
961Please respect copyright.PENANAdlAHJ9vaFJ
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。961Please respect copyright.PENANAuPfSCyXN5V
961Please respect copyright.PENANAVlIs83i98X
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。961Please respect copyright.PENANAvMr0tUXYut
961Please respect copyright.PENANADODEUpj1f7
961Please respect copyright.PENANAoLPnO1J2vo
(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)。961Please respect copyright.PENANA1uuUsZO6eq961Please respect copyright.PENANAE3qzGEMaPb
961Please respect copyright.PENANA9XPwL1lMqc
Cadmium sulfide,為該時期常用作為黃色顏料的化學物。961Please respect copyright.PENANAM6EtGJqqLO
961Please respect copyright.PENANAg66STx8qIU
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。961Please respect copyright.PENANANfbtOJLRoj
961Please respect copyright.PENANA2p4ddrBPYi
該時期主要有兩種方式製作Cadmium sulfide,分別為Dry及Wet Method。961Please respect copyright.PENANAhxNSeqNA22
961Please respect copyright.PENANAAXfqZD8C6d
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。961Please respect copyright.PENANAEDdLb3AXwu
961Please respect copyright.PENANA8uLlalaNRL
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。961Please respect copyright.PENANAA7WvYvWBQY
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。961Please respect copyright.PENANAwb7IOynGKX
961Please respect copyright.PENANAU0sjYGqXBA
(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。961Please respect copyright.PENANA5ZBeeqNv2d961Please respect copyright.PENANAcjrGGYn1rj
961Please respect copyright.PENANANibtf4NVbs
圖3中間的圖片,其紅點代表黃色顏料Cadmium sulfide的存在。961Please respect copyright.PENANAxXp2Ocr69v
961Please respect copyright.PENANARss6ly9kXo
下方的圖片,其三種顏色的出現分別代表Wet Method的副產物。961Please respect copyright.PENANANslF3vuo3M
961Please respect copyright.PENANAVvLU6ziuEf
紅點:Cd(OH)Cl961Please respect copyright.PENANADrCsA7Js3z
綠點:CdSO4961Please respect copyright.PENANAyLu3J0vGmG
藍點:CdCO3961Please respect copyright.PENANAWjnQvkOOFQ
961Please respect copyright.PENANAMsHPt4jX3c
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。961Please respect copyright.PENANAk6tvT27AYK
961Please respect copyright.PENANAmBQN01lKRN
(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)。961Please respect copyright.PENANAtMqcRJThQi961Please respect copyright.PENANACXAj6haZH6
961Please respect copyright.PENANAFMfRSiXhgA
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)。961Please respect copyright.PENANA1SLPASOtxy
961Please respect copyright.PENANACHfnPjERbi
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。961Please respect copyright.PENANAfbR10pY7HD
961Please respect copyright.PENANAtNuCWfhFJa
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。961Please respect copyright.PENANAkawe4IQORK
961Please respect copyright.PENANAjs13CG50tB
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。961Please respect copyright.PENANALLZMa67IKZ
961Please respect copyright.PENANA9K6tOKUpd8
961Please respect copyright.PENANA0TtpdDeAOr
(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。961Please respect copyright.PENANA0JKWQpA5XJ961Please respect copyright.PENANAthDe1hzndl
961Please respect copyright.PENANAB6hhS5Ypgk
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)。961Please respect copyright.PENANAYZ9TAbdJXU
961Please respect copyright.PENANAFBEixIanEk
(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。961Please respect copyright.PENANA2C74lhBoeH
961Please respect copyright.PENANAp36BWfOLIT
961Please respect copyright.PENANAuYz0SusHNp
(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。961Please respect copyright.PENANAvdzAgYLpaQ961Please respect copyright.PENANAnZvFOM3tGa
961Please respect copyright.PENANAoCLU3hTvcr
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。961Please respect copyright.PENANAjQjftycpfR
961Please respect copyright.PENANAZUBcrnKByw
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。961Please respect copyright.PENANAuoQt9lNzFK
961Please respect copyright.PENANAqN4nNm5TPX
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/toc961Please respect copyright.PENANAzWdZHdMUV2
961Please respect copyright.PENANA2e5h3idX8h
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。961Please respect copyright.PENANApFX3WHcCvw
961Please respect copyright.PENANAJWzc25oXTk
Link:961Please respect copyright.PENANAg8AEqXeSIg
https://www.penana.com/user/27349/%E8%96%AF%E4%BB%94%E8%81%9E%E8%8C%B1%E8%8E%89/portfolio961Please respect copyright.PENANA4oo3iNPtRH
961Please respect copyright.PENANAXLZGZcCfoI
961Please respect copyright.PENANApwneqYNT3K
有興趣接收科學資訊的話,歡迎follow IG: potatopigtongue。961Please respect copyright.PENANAfHQo7kJ70L
961Please respect copyright.PENANAFqh00Tr0lz
Ref1:https://advances.sciencemag.org/content/6/20/eaay3514961Please respect copyright.PENANA1Dk5OunCiG