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塌陷(xian)(xian)溫(wen)(wen)度(du)(du)(du)(du)(du)(Collapse temperature, Tc)也叫崩解(jie)溫(wen)(wen)度(du)(du)(du)(du)(du)，是(shi)指凍(dong)干時(shi)，干燥層溫(wen)(wen)度(du)(du)(du)(du)(du)上升到(dao)一(yi)定數值時(shi)，物(wu)料中(zhong)的冰晶消失(shi)，原先為冰晶所占據(ju)的空間成(cheng)為空穴，因此凍(dong)干層呈多孔蜂窩(wo)狀海綿體(ti)結(jie)構(gou)(gou)。此結(jie)構(gou)(gou)與溫(wen)(wen)度(du)(du)(du)(du)(du)有關(guan)。當蜂窩(wo)狀結(jie)構(gou)(gou)體(ti)的固(gu)體(ti)基質溫(wen)(wen)度(du)(du)(du)(du)(du)較高時(shi)，物(wu)料剛性降低。當溫(wen)(wen)度(du)(du)(du)(du)(du)達到(dao)某一(yi)臨(lin)界(jie)(jie)值時(shi)，固(gu)體(ti)基質的剛性不足以維持蜂窩(wo)狀結(jie)構(gou)(gou)，空穴的固(gu)形物(wu)基質壁將(jiang)發(fa)生(sheng)塌陷(xian)(xian)，原先蒸(zheng)汽擴散的通道被封閉，此臨(lin)界(jie)(jie)溫(wen)(wen)度(du)(du)(du)(du)(du)稱為凍(dong)干物(wu)料的崩潰溫(wen)(wen)度(du)(du)(du)(du)(du)或塌陷(xian)(xian)溫(wen)(wen)度(du)(du)(du)(du)(du)。（簡化(hua)版含義(yi)：在(zai)凍(dong)干升華階段(duan)，隨著溫(wen)(wen)度(du)(du)(du)(du)(du)上升，物(wu)料失(shi)去剛性，開始變粘，發(fa)生(sheng)類似塌方的崩解(jie)、熔化(hua)或產生(sheng)發(fa)泡現象時(shi)的溫(wen)(wen)度(du)(du)(du)(du)(du)。）

  塌(ta)(ta)陷(xian)溫度與凍(dong)(dong)(dong)干(gan)(gan)(gan)制品(pin)的品(pin)質關系(xi)：凍(dong)(dong)(dong)干(gan)(gan)(gan)過程中(zhong)發(fa)(fa)生(sheng)(sheng)塌(ta)(ta)陷(xian)會嚴(yan)重影響(xiang)凍(dong)(dong)(dong)干(gan)(gan)(gan)制品(pin)品(pin)質，因此需要(yao)在物料凍(dong)(dong)(dong)干(gan)(gan)(gan)過程中(zhong)防止塌(ta)(ta)陷(xian)的發(fa)(fa)生(sheng)(sheng)，塌(ta)(ta)陷(xian)主要(yao)與產品(pin)工藝和(he)物料本身性(xing)質有關。不同的凍(dong)(dong)(dong)干(gan)(gan)(gan)參數會對塌(ta)(ta)陷(xian)發(fa)(fa)生(sheng)(sheng)產生(sheng)(sheng)影響(xiang)。

  塌陷溫(wen)(wen)(wen)度也受物(wu)料(liao)本身的(de)(de)物(wu)理性質影響，有(you)的(de)(de)物(wu)料(liao)崩解溫(wen)(wen)(wen)度高于共晶(jing)(jing)點(dian)溫(wen)(wen)(wen)度，進行凍(dong)(dong)干(gan)操作時(shi)要控制產(chan)品溫(wen)(wen)(wen)度低于共晶(jing)(jing)點(dian)溫(wen)(wen)(wen)度;有(you)的(de)(de)物(wu)料(liao)的(de)(de)崩解溫(wen)(wen)(wen)度低于共晶(jing)(jing)點(dian)溫(wen)(wen)(wen)度，進行凍(dong)(dong)干(gan)操作時(shi)應以密切關注(zhu)崩解溫(wen)(wen)(wen)度。目前，塌陷溫(wen)(wen)(wen)度測量(liang)比較困(kun)難，需要借助專門的(de)(de)測試儀器才能進行測量(liang)。