[{"data":1,"prerenderedAt":73},["ShallowReactive",2],{"q-fire-110-1-fire-science-014":3},{"subject":4,"subjectSlug":5,"subjectKicker":6,"subjectShort":7,"question":8,"related":27,"sameNumber":52,"hasEssay":26},"火災學概要","fire-science","火災學 · Fire Science","火災學",{"id":9,"webId":10,"year":11,"session":12,"subject":4,"number":13,"stem":14,"options":15,"answer":20,"answerNote":21,"images":22,"imagesPending":23,"lawTimestamp":11,"explanation":24,"explanationDeep":25,"freq":12,"indexable":26},"fire-110-1-火災學概要-014","fire-110-1-fire-science-014",110,1,14,"自然發火性物質中的原棉，主要是因為下列何種熱之蓄積而發火？",{"A":16,"B":17,"C":18,"D":19},"分解熱","氧化熱","吸著熱","發酵熱","B",null,[],false,"本題考點：自然發火（自燃）的四種蓄熱型態，以及原棉屬於其中何者。\n【正解理由】自然發火的成因依發熱來源分為氧化熱、分解熱、吸著熱與發酵熱四型。原棉為纖維素纖維，纖維表面積極大且常含微量油脂，堆積打包後與空氣接觸緩慢氧化並持續放熱，內部散熱不良而蓄熱升溫，終至達到發火點，屬氧化熱型自然發火，故選 B。\n【逐項排除】\n(A) 分解熱型指物質自身分子不安定而自行分解放熱，代表物為硝化纖維素、賽璐珞、硝化甘油，機制不需外來氧，與原棉不同。\n(B) 氧化熱型的代表物正是原棉、乾性油浸漬的破布、煤、橡膠屑與金屬粉末，皆藉與空氣中氧的緩慢氧化蓄熱，敘述正確。\n(C) 吸著熱型指多孔材料吸附水蒸氣或氣體時放熱，代表物為活性碳與木炭，原棉的吸濕放熱量不足以構成主要發火機制。\n(D) 發酵熱型來自微生物代謝產熱，代表物為堆肥、廄肥、乾草與稻稈，原棉經加工除雜，並非以微生物發酵為主因。\n【記憶點】原棉、乾性油、煤看氧化熱；賽璐珞看分解熱；活性碳看吸著熱；堆肥看發酵熱。","自然發火成立需要兩個條件同時滿足：發熱速率大於散熱速率，且蓄熱環境使溫度得以持續累積。前者取決於物質的反應性與比表面積，後者取決於堆積形狀、堆高、通風與保溫程度。這也是為什麼同一批原棉散置時安然無事，一旦大量打包堆疊、中心散熱路徑變長，就可能自行升溫發火。熱爆炸理論中的 Semenov 模型與 Frank-Kamenetskii 模型即在描述此一發熱與散熱曲線的臨界關係，臨界堆積尺寸隨環境溫度上升而縮小。\n四型的代表物值得整理成表：氧化熱型為原棉、乾性油與其浸漬物、煤、鐵粉、橡膠屑；分解熱型為硝化纖維素、賽璐珞、硝化甘油；吸著熱型為活性碳、木炭、矽膠；發酵熱型為堆肥、乾草、廄肥、稻稈；另有聚合熱型，如苯乙烯等單體因聚合放熱而失控。\n氧化熱型中最典型的推手是乾性油。油脂的碘價愈高代表不飽和雙鍵愈多，愈易與氧結合放熱，亞麻仁油碘價約 175 以上屬乾性油，浸過亞麻仁油的抹布堆置在通風不良處而起火的案例，是教科書標準範例；棉纖維本身雖以纖維素為主，但其巨大的比表面積與夾帶的油脂、加工助劑，使氧化放熱得以在堆體中心累積。\n防範原理與考點相互呼應：控制堆置高度與堆間距離以增加散熱面、維持庫房通風降低環境溫度、管制含水率避免同時誘發微生物發酵、含油纖維廢料另以密閉金屬容器收存隔絕空氣。延伸考法常見於問「下列何者屬分解熱自燃」「乾性油自燃與碘價的關係」「堆積高度對自燃臨界的影響」，判準一律回到發熱來源與散熱條件這兩支。",true,[28,32,36,40,44,48],{"webId":29,"stem":30,"number":31,"year":11,"session":12},"fire-110-1-fire-science-013","有一開口面積為 10.0 m2，開口高度為 1.44 m 之居室，當其發生火災而形成通風控制燃燒時，根據 P. H. Thomas 之研究結果，則燃燒速度為多少 kg\u002Fmin？",13,{"webId":33,"stem":34,"number":35,"year":11,"session":12},"fire-110-1-fire-science-015","下列有關液化天然氣（LNG）與液化石油氣（LPG）之比較，何者正確？",15,{"webId":37,"stem":38,"number":39,"year":11,"session":12},"fire-110-1-fire-science-012","根據 NFPA265 對閃燃現象（flashover）之定義，下列敘述何者錯誤？",12,{"webId":41,"stem":42,"number":43,"year":11,"session":12},"fire-110-1-fire-science-016","市面上販售的 ABC 乾粉滅火器內充填的乾粉滅火藥劑主要成分為：",16,{"webId":45,"stem":46,"number":47,"year":11,"session":12},"fire-110-1-fire-science-011","輻射熱是造成木造建築物延燒原因之一，下列何者正確？",11,{"webId":49,"stem":50,"number":51,"year":11,"session":12},"fire-110-1-fire-science-017","下列惰性氣體類海龍替代滅火藥劑中，何者的比重小於 1？",17,[53,57,61,65,69],{"webId":54,"year":55,"stem":56,"number":13},"fire-111-1-fire-science-014",111,"普通木造建築物旁欲蓋 9 公尺高之建築物，其延燒係數為 3 級（係數為 0.15），其防火間隔應保持多少公尺？",{"webId":58,"year":59,"stem":60,"number":13},"fire-109-1-fire-science-014",109,"火場溫度隨燃燒時間而逐漸升高，其空氣亦漸膨脹，空氣由外界流入該起火房間，同時熱煙霧也會從該起火房間流出。若忽略燃燒分解過程而產生之質量流率，建築物內部空氣溫度為 25℃，起火房間溫度為 800℃，流入起火房間之空氣體積流量為 1 m3\u002Fs，則流出起火房間之熱煙霧體積流量約為若干？",{"webId":62,"year":63,"stem":64,"number":13},"fire-108-1-fire-science-014",108,"依 Thomas 閃燃公式（Thomas Flashover Correlation），有關室內火災發生閃燃所需最小釋熱率，下列敘述何者錯誤？",{"webId":66,"year":67,"stem":68,"number":13},"fire-107-1-fire-science-014",107,"我國在 106 年實施 A1、A2、A3 新式火災認定方式，下列有關 A2 火災認定之敘述，何者錯誤？",{"webId":70,"year":71,"stem":72,"number":13},"fire-106-1-fire-science-014",106,"在乙炔氣瓶內加入丙酮以溶解乙炔氣，主要是防止那一種爆炸？",1785123162364]