章學(xué)來(lái)，王迎輝，紀(jì) 珺，劉俊名，李玉洋, 韓興超，徐笑鋒，周孫希，劉 璐，劉 升

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山梨酸鉀/氯化鉀復(fù)合相變材料制備及熱物性分析

章學(xué)來(lái)1，王迎輝1，紀(jì) 珺1，劉俊名2，李玉洋1, 韓興超1，徐笑鋒1，周孫希1，劉 璐1，劉 升3

(1. 上海海事大學(xué)蓄冷技術(shù)研究所，上海 201306；2. 中建安裝工程有限公司，南京 210000 3. 北京市農(nóng)林科學(xué)院蔬菜研究中心，北京 100097)

為開(kāi)發(fā)出高效、性能穩(wěn)定的微凍保鮮用相變蓄冷劑，保證運(yùn)輸中肉制品等農(nóng)產(chǎn)品的品質(zhì)，以山梨酸鉀水溶液為主基液，探究添加氯化鉀后相變蓄冷材料的熱物性及熱循環(huán)穩(wěn)定性。對(duì)比30 g/L山梨酸鉀溶液，當(dāng)再添加氯化鉀濃度為5 g/L時(shí)，相變溫度為-2.8 ℃，潛熱為254.6 J/g，熱導(dǎo)率為1.012 W/(m·K)，熱擴(kuò)散率為1.01 mm2/s。添加氯化鉀對(duì)相變溫度和潛熱幾乎沒(méi)有影響；溶液的熱導(dǎo)率提高了23.32 %；熱擴(kuò)散率提高了151.37%。經(jīng)200次凍融循環(huán)后，未添加氯化鉀的相變?nèi)芤撼霈F(xiàn)了-5.3 ℃的過(guò)冷度，含氯化鉀的相變?nèi)芤簺](méi)有過(guò)冷度，氯化鉀在山梨酸鉀相變過(guò)程中體現(xiàn)出了其良好的成核作用，使得該復(fù)合相變蓄冷劑具有優(yōu)異的熱穩(wěn)定性。試驗(yàn)表明，山梨酸鉀/氯化鉀復(fù)合相變蓄冷劑適合于農(nóng)產(chǎn)品的微凍保鮮用。

冷藏；相變材料；熱力學(xué)性質(zhì)；穩(wěn)定性

0 引 言

農(nóng)產(chǎn)品是食品冷鏈物流中的主要銷(xiāo)售對(duì)象，由于產(chǎn)品本身的特性，極易出現(xiàn)損害和腐爛，造成嚴(yán)重的損失[1]。隨著生活水平的提高，人們對(duì)于肉制品、果蔬等微凍保鮮的質(zhì)量需求增加，為迎合社會(huì)發(fā)展趨勢(shì)，在農(nóng)產(chǎn)品最先一公里和最后一公里中開(kāi)發(fā)出更高效的冷發(fā)電和儲(chǔ)存技術(shù)尤為關(guān)鍵。相變材料在吸放熱時(shí)的相變潛熱可以對(duì)能量進(jìn)行高效地儲(chǔ)存，這使得其在食品冷藏保鮮[2-5]、溫室應(yīng)用[6-8]、疫苗低溫儲(chǔ)運(yùn)[9-11]等系統(tǒng)中得到廣泛的研究與應(yīng)用。相變材料作為儲(chǔ)能技術(shù)的重中之重，國(guó)內(nèi)外學(xué)者對(duì)此展開(kāi)了大量的研究，集中于有機(jī)復(fù)合[12-15]、無(wú)機(jī)復(fù)合[16-17]、有機(jī)–無(wú)機(jī)復(fù)合相變材料的研究[18-19]等。一些鹽溶液由于其較大的潛熱以及合適的相變溫度，被廣泛應(yīng)用為蓄冷材料[20-21]，但由于部分材料過(guò)冷度較大且易于相分離、熱穩(wěn)定性差，成為鹽溶液作為理想相變蓄冷材料的主要棘手問(wèn)題[22]。

有機(jī)鹽溶液[23-25]克服了有機(jī)物的低熱導(dǎo)率和較小潛熱、無(wú)機(jī)材料過(guò)冷度大和相分離的缺點(diǎn)。紀(jì)珺等[26]通過(guò)試驗(yàn)測(cè)試知質(zhì)量分?jǐn)?shù)29.4 %的甲酸鈉水溶液相變溫度為-16℃，潛熱250.4 J/g，熱導(dǎo)率為0.938 W/m·K，遠(yuǎn)高于有機(jī)酸類(lèi)相變材料，且經(jīng)過(guò)多次循環(huán)試驗(yàn)后確定有機(jī)鹽的熔融和結(jié)晶性能良好。應(yīng)鐵進(jìn)等[27]通過(guò)調(diào)節(jié)甘氨酸濃度，得到相變溫度及潛熱可調(diào)的系列有機(jī)物水溶液相變蓄冷劑，且無(wú)明顯過(guò)冷和相分離現(xiàn)象。

有機(jī)鹽山梨酸鉀（C5H7COOK）是一種廣泛而有效的防腐劑[28]，易溶于水，密封狀態(tài)下穩(wěn)定且不易分解，有很強(qiáng)的抑制腐敗菌和霉菌作用，且價(jià)格低廉易得。但是作為相變蓄冷材料，C5H7COOK卻少有涉及。氯化鉀（KCl）作為常用的低溫蓄冷材料之一，作為相變溫度調(diào)節(jié)劑的使用研究居多[29-31]。本文將以目前食品冷鏈物流研究領(lǐng)域有限的介于水溫冷藏區(qū)的-2~-3℃為目標(biāo)溫度，采用有機(jī)物和無(wú)機(jī)物復(fù)合，以C5H7COOK、KCl和H2O構(gòu)成的三元復(fù)合物作為復(fù)合相變蓄冷劑，通過(guò)調(diào)整配比，研制一種相變溫度（Onset溫度）在-2~-3℃的蓄冷劑，并通過(guò)一系列試驗(yàn)探究該復(fù)合相變材料的熱物性及熱穩(wěn)定性，旨在為農(nóng)產(chǎn)品的水溫冷藏儲(chǔ)運(yùn)技術(shù)的深入研究和應(yīng)用提供參考。

1 材料和方法

1.1 試劑與儀器

C5H7COOK、KCl，均為AR分析純；山梨酸鉀是國(guó)際糧農(nóng)組織和衛(wèi)生組織推薦的高效安全的防腐保鮮劑，廣泛應(yīng)用于食品、飲料、農(nóng)藥等行業(yè)，有效地解決了蓄冷劑在長(zhǎng)期使用下存在的細(xì)菌滋生問(wèn)題。

試驗(yàn)儀器主要有：電子分析天平（精度0.1 mg）；安捷倫溫度時(shí)間采集儀；T型熱電偶（精度± 0.01 ℃）；數(shù)顯磁力恒溫?cái)嚢杵?；差示掃描量熱儀DSC200 F3（溫度精度0.1 ℃，熱焓精度0.1 %，量熱靈敏度0.1W）；熱常數(shù)分析儀Hot Disk TPS 2500S型（誤差2%）；熱成像儀FLIR（熱靈敏度< 0.05℃，測(cè)溫準(zhǔn)確度1.0 ℃）；低溫恒溫槽；高低溫交變?cè)囼?yàn)箱YSGJW-100C型。

1.2 試驗(yàn)方法

1.2.1 C5H7COOK的濃度優(yōu)選

本文選擇C5H7COOK水溶液作為主儲(chǔ)能劑，利用高精度電子天平稱(chēng)取不同質(zhì)量的山梨酸鉀，配制50 mL C5H7COOK濃度分別為10、20、30、40、50、60 g/L的水溶液，并將其分別放在磁力攪拌器上加熱至30℃，并用磁性粒子攪拌30 min使其混合均勻。通過(guò)C5H7COOK溶液的步冷曲線(xiàn)確定試驗(yàn)蓄冷工況，通過(guò)DSC曲線(xiàn)圖確定滿(mǎn)足水溫冷藏區(qū)溫度要求的濃度。

1）步冷試驗(yàn)：根據(jù)試驗(yàn)要求，搭建的試驗(yàn)平臺(tái)如圖1所示，量取50 mL充分混合的復(fù)合相變材料置于100 mL燒杯中放入-30℃的低溫恒溫槽中，將T型熱電偶插入燒杯后做好密封處理。按3 s的時(shí)間間隔記錄樣品溫度變化，并根據(jù)溫度與時(shí)間關(guān)系，繪制步冷曲線(xiàn)。

圖1 步冷試驗(yàn)裝置圖

2）DSC測(cè)試：稱(chēng)量5~10 mg樣品放置在鋁制坩堝中心部分，壓機(jī)密封后放入儀器。為了消除試樣的熱歷史，對(duì)樣品在-30℃（溫度下限）與20℃（溫度上限）之間以20 ℃/min的速率降升溫2次即可。在溫度降至-30℃時(shí)恒溫3 min確保材料完全凝固后，以5 ℃/min的速率升溫至20℃。在得到的DSC融解曲線(xiàn)中，吸熱峰的最大斜率與基線(xiàn)相交得到的溫度即為相變溫度（Onset溫度），雖然Onset溫度不是起始融解溫度，但是Onset溫度之后才開(kāi)始大量吸熱，所以考察Onset溫度更符合實(shí)際意義[32]。

1.2.2 C5H7COOK/KCl制備與性能測(cè)試

向30 g/L C5H7COOK溶液中分別添加不同質(zhì)量的KCl，制備的KCl濃度分別為3、5、7、10和20 g/L的復(fù)合相變蓄冷劑，使用磁力恒溫?cái)嚢杵鲗⑵浠旌暇鶆?。通過(guò)DSC試驗(yàn)結(jié)果得到滿(mǎn)足條件的C5H7COOK/KCl最佳配比，通過(guò)測(cè)量其熱導(dǎo)率、蓄冷特性以及熱循環(huán)穩(wěn)定性分析C5H7COOK/KCl復(fù)合相變材料熱性能。

熱物性測(cè)試：采用熱常數(shù)分析儀測(cè)量材料的熱導(dǎo)率、熱擴(kuò)散率、比熱。儀器預(yù)熱30 min，為防止空氣對(duì)流影響試驗(yàn)結(jié)果，測(cè)量過(guò)程中將熱導(dǎo)率測(cè)量探頭C5465插入復(fù)合相變材料中并放置在密閉箱中，環(huán)境溫度維持在20 ℃。

熱循環(huán)穩(wěn)定性測(cè)試：為了準(zhǔn)確模擬夏季蓄冷材料的使用工況，用燒杯量取30 mL復(fù)合相變材料，密封處理后放入溫度段設(shè)置為-20~40 ℃的高低溫交變?cè)囼?yàn)箱內(nèi)，循環(huán)周期為90 min。完成200次凍融循環(huán)后，對(duì)比溶液循環(huán)前后的熱性能變化。

2 結(jié)果與分析

2.1 C5H7COOK的濃度優(yōu)選

2.1.1 不同蓄冷工況下過(guò)冷度研究

過(guò)冷度作為相變材料的重要特性，蓄冷工況對(duì)相變材料的過(guò)冷度以及蓄冷時(shí)間有很大的影響。C5H7COOK水溶液步冷試驗(yàn)結(jié)果如圖2所示，在-10℃的蓄冷環(huán)境下，濃度分別為10、20、30、40、50、60 g/L的C5H7COOK水溶液均存在著較大的過(guò)冷度，分別為7.754、7.333、6.23、4.411、6.276、6.067 ℃。在-20℃的蓄冷環(huán)境下，只有濃度為10 g/L的C5H7COOK溶液存在1.427 ℃的過(guò)冷，其余濃度的過(guò)冷度已經(jīng)消除，且相變蓄冷時(shí)間明顯縮短。在-30℃的蓄冷環(huán)境下，不同濃度的C5H7COOK溶液均無(wú)過(guò)冷現(xiàn)象。

圖2 不同蓄冷工況對(duì)山梨酸鉀水溶液過(guò)冷度的影響

出現(xiàn)該情況的原因可能是隨著蓄冷環(huán)境溫度的降低，促成C5H7COOK溶液在相變階段產(chǎn)生二次成核現(xiàn)象，該過(guò)程中成核基體的存在，可以大大降低成核位壘，使得成核在較小的過(guò)冷度下即可進(jìn)行?？紤]到耗能以及排除過(guò)冷度的影響因素，本文選擇-20℃為蓄冷工況進(jìn)行以下試驗(yàn)。

2.1.2 DSC測(cè)試

相變溫度和潛熱對(duì)蓄冷材料的應(yīng)用起到了關(guān)鍵性作用。山梨酸鉀水溶液的DSC(differencial scanning calorimentry)試驗(yàn)結(jié)果如圖3、圖4所示。

圖3 不同濃度山梨酸鉀水溶液的DSC曲線(xiàn)

圖4 不同濃度的山梨酸鉀水溶液相變溫度及潛熱

由圖3的DSC曲線(xiàn)可知，該復(fù)合溶液相溶性較好，且隨著其濃度的增加，相變起始點(diǎn)逐漸向左偏移，曲線(xiàn)所圍成的面積也在逐漸減?。挥蓤D4更加直觀地表達(dá)了隨著山梨酸鉀水溶液濃度的增加相變溫度及潛熱逐漸減小。這是由于山梨酸鉀水溶液中，水的相變潛熱較大，隨著山梨酸鉀濃度的增加，水的占比減小，其潛熱值也逐漸減小。

在濃度為10 ~60 g/L范圍內(nèi)，山梨酸鉀水溶液的相變潛熱由307.9減小至197.7 J/g。為了篩選出符合水溫冷藏區(qū)所要求的溫度-2~-3 ℃，濃度為30、40 g/L的山梨酸鉀水溶液相變溫度都在該范圍內(nèi)，選擇潛熱稍高的30 g/L山梨酸鉀水溶液作為復(fù)合相變材料主基液，其Onset溫度為-2.5 ℃，潛熱為256.2 J/g；且在-20 ℃蓄冷工況下，由步冷曲線(xiàn)知山梨酸鉀溶液在該濃度下無(wú)過(guò)冷。

2.2 C5H7COOK/KCl儲(chǔ)能劑復(fù)配

2.2.1 C5H7COOK/KCl最佳配比

C5H7COOK/KCl復(fù)合相變材料的DSC測(cè)試結(jié)果如圖5所示。當(dāng)KCl濃度為3和5 g/L時(shí)，復(fù)合相變材料DSC曲線(xiàn)只有1個(gè)峰，C5H7COOK與KCl的相溶性較好；當(dāng)KCl濃度為7 g/L時(shí)，DSC曲線(xiàn)開(kāi)始出現(xiàn)2個(gè)峰，山梨酸鉀水溶液不能再溶解更多的KCl，在相變過(guò)程中開(kāi)始發(fā)生相分離，隨著KCl濃度的增加，2個(gè)峰值越加明顯。當(dāng)KCl濃度為5 g/L時(shí)，Onset溫度為-2.8 ℃，潛熱為254.6 J/g；對(duì)比未添加KCl前，相變溫度降低了-0.3 ℃，潛熱降低了1.6 J/g，該變化符合濃度配比的線(xiàn)性關(guān)系，說(shuō)明山梨酸鉀和KCl沒(méi)有發(fā)生化學(xué)反應(yīng)。綜上，較少量的KCl對(duì)山梨酸鉀水溶液的相變溫度及潛熱影響不大。因此，選擇山梨酸鉀、氯化鉀水溶液濃度分別為30、5 g/L作為復(fù)配材料的最佳濃度配比。

圖5 30 g·L-1山梨酸鉀復(fù)配不同濃度KCl的DSC曲線(xiàn)

2.2.2 C5H7COOK/KCl熱性能

對(duì)最佳配比的C5H7COOK/KCl溶液在-20℃的蓄冷工況下進(jìn)行步冷曲線(xiàn)的測(cè)試結(jié)果如圖6所示，添加KCl后，溶液的Onset溫度稍有降低，符合DSC測(cè)試結(jié)果。C5H7COOK/KCl溶液的熱導(dǎo)率、熱擴(kuò)散率和比熱由熱常數(shù)分析儀Hot Disk測(cè)量結(jié)果如表1所示。

圖6 -20℃蓄冷工況下有無(wú)添加KCl的蓄冷劑步冷曲線(xiàn)對(duì)比

以30 g/L C5H7COOK為主基液的相變蓄冷劑，內(nèi)含5 g/L KCl的溶液熱導(dǎo)率為1.012 W/(m·K)，增大了23.32%；比熱容為1.002 MJ/(m3·K)，降低了50.95%，結(jié)合步冷曲線(xiàn)可知，比熱越小，降低相同的溫度釋放的熱量越少，越易降溫；由/()，熱導(dǎo)率增大，比熱減小，則熱擴(kuò)散率增大。由表1知，添加5 g/L 濃度KCl的C5H7COOK水溶液的熱擴(kuò)散率為1.01 mm2/s，較未添加KCl增大了151.37%。從物體溫度變化的角度看，熱擴(kuò)散率越大，表示物體內(nèi)部溫度變化傳播得越快速。圖7所示的6張熱成像圖是每隔3 s拍攝，從圖中可以明顯地看出添加少量KCl的相變?nèi)芤涸谙嗤沫h(huán)境溫度下明顯釋冷更快，該現(xiàn)象也進(jìn)一步驗(yàn)證了Hot Disk試驗(yàn)結(jié)果的準(zhǔn)確性。

表1 溶液的熱物性測(cè)量數(shù)據(jù)

2.2.3 C5H7COOK/KCl熱穩(wěn)定性

試驗(yàn)樣品經(jīng)過(guò)200次凍融循環(huán)試驗(yàn)后，由DSC的分析軟件獲得C5H7COOK/KCl溶液的相變潛熱、峰溫及相變起始與結(jié)束溫度。如圖8所示，C5H7COOK/KCl溶液相變起始溫度為-2.6 ℃，較循環(huán)前增加了0.2 ℃；潛熱值為236 J/g，較循環(huán)前降低了7.31 %；相變溫度及潛熱經(jīng)過(guò)200次循環(huán)試驗(yàn)后變化不大。

注：圖中A1~A6指未添加氯化鉀的30 g/L山梨酸鉀水溶液、B1~B6指含0.5 g/L氯化鉀的30 g/L山梨酸鉀水溶液

圖8 凍融循環(huán)200次后C5H7COOK/KCl水溶液的DSC曲線(xiàn)

為了進(jìn)一步研究C5H7COOK/KCl水溶液的熱穩(wěn)定性，在-20 ℃的蓄冷工況下凍融循環(huán)200次后C5H7COOK水溶液和C5H7COOK/KCl水溶液的步冷曲線(xiàn)如圖9所示，未添加KCl的復(fù)合相變材料出現(xiàn)了-5.3 ℃的過(guò)冷度，該現(xiàn)象說(shuō)明30 g/L C5H7COOK溶液并不具備良好的熱穩(wěn)定性，而含5 g/L KCl的復(fù)合相變?nèi)芤阂廊粵](méi)有出現(xiàn)過(guò)冷度，對(duì)比循環(huán)試驗(yàn)表明KCl在C5H7COOK溶液相變過(guò)程中起到良好的成核作用，使得該復(fù)合相變蓄冷劑在循環(huán)使用過(guò)程中保持優(yōu)異的熱穩(wěn)定性。

圖9 蓄冷劑凍融循環(huán)試驗(yàn)步冷曲線(xiàn)

3 結(jié) 論

為了尋求微凍保鮮用相變蓄冷劑，試驗(yàn)以山梨酸鉀水溶液為主蓄冷劑，探究了添加少量KCl前后蓄冷劑的熱性能。本文通過(guò)試驗(yàn)研究主要得出結(jié)論如下：

1）不同的蓄冷工況對(duì)山梨酸鉀水溶液的過(guò)冷度影響較大。山梨酸鉀水溶液濃度為30 g/L時(shí)，-20 ℃的蓄冷工況下沒(méi)有過(guò)冷度，此時(shí)相變溫度為-2.5 ℃，潛熱為256.2 J/g；

2）30g/L C5H7COOK溶液內(nèi)含5 g/L KCl時(shí)，該復(fù)合溶液蓄冷性能最佳。此時(shí)C5H7COOK/KCl復(fù)合相變材料相變溫度為-2.8 ℃，潛熱為254.6 J/g，熱導(dǎo)率為1.012 W/(m·K)，提高了23.32%；熱擴(kuò)散率為1.01 mm2/s，提高了151.37%，熱擴(kuò)散率越大，物體內(nèi)部溫度變化傳播得越快速；

3）經(jīng)200次凍融循環(huán)后，C5H7COOK/KCl復(fù)合溶液的相變溫度和潛熱變化不大。在-20℃的蓄冷工況下， KCl在C5H7COOK溶液中起到良好的成核作用，該復(fù)合相變蓄冷劑具有優(yōu)異的熱穩(wěn)定性。

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Preparation and thermal performance analysis of C5H7COOK/KCl composite phase change material

Zhang Xuelai1, Wang Yinghui1, Ji Jun1, Liu Junming2, Li Yuyang1, Han Xingchao1, Xu Xiaofeng1, Zhou Sunxi1, Liu Lu1, Liu Sheng3

(1.,201306;2..,,210000;3,100097,)

In the process of handover, strict logistics quality standards and inspection methods are lacking in food logistics enterprises. It makes the “broken chain” and “being not cold” of fresh and perishable low-temperature products become common phenomena during fresh and perishable low-temperature products’ transportation. At present, distribution of fresh food is not effective with the application of modern technology and the implementation of the “first mile” sorting and pre-cooling scheme, and the “l(fā)ast mile” is still dominated by the traditional ways of circulation model represented by “ice pack & plastic foam box”. Meanwhile, the cold storage, of which the main function is cargo-storing, often does not have the ability to sort, flow and process, so it restricts the effective improvement of the cold chain logistics’ service level seriously. It is particularly critical to develop more efficient storage technologies with respect to the “first mile” and the “l(fā)ast mile” of agricultural products. Water temperature refrigerated preservation(range from -2 to -3℃) belongs to the temperature interval of micro-frozen and fresh-keeping, and it is also a concept proposed for meat products, fruits and vegetables, etc. It can not only inhibit the growth of microorganisms effectively, but also keep food nutrients from being lost compared to traditional refrigeration technology. In order to develop a stable and efficient phase change coolants for micro-frozen and fresh-keeping to ensure the quality of agricultural products, such as meat products in transportation, the ternary complex composed of C5H7COOK, KCl and H2O was prepared in this article. Considering that the cold storage condition has a great influence on the supercooling degree and cooling rate, -20℃ was selected firstly as the cooling medium temperature in this article via testing the step cooling characteristics of the PCM under different cold storage conditions; the optimal concentration of main base solution was determined by DSC (Differential Scanning Calorimeter) experiment. Then mixing KCl with it, thermodynamic properties and thermal cycle stability of the composite material were studied by Hot Disk thermal constant analyzer, DSC, Agilent temperature time recorder, low-temperature thermostat bath and other equipment. When KCl was added, under concentration of 5 g/L, into the 3 g/L C5H7COOK solution, DSC results indicated that the onset temperature and latent heat were measured as -2.8℃ and 254.6 J/g, which were reduced by -0.3°C and 1.6 J/g respectively. It was indicated that there was no chemical reaction between C5H7COOK and KCl, since there shows a linear relationship between the change of properties and concentration ratio. The thermal conductivity of C5H7COOK/KCl solution was measured as 1.012 W/m·K with an increase of 23.32 %; the specific heat capacity was 1.002 MJ/m3K with a decrease of 50.95 %, and thermal diffusivity was 1.01 mm2/s with an increase of 151.37 %. From the point of view of temperature, the higher the thermal diffusivity, the faster the propagation of internal temperature variation. Thermal cycling test results revealed that the changes of the phase change temperature and latent heat of the C5H7COOK/KCl composite solution were not obvious after 200 freeze-thaw cycles. Under condition of -20℃ in cold storage, the composite PCM added with KCl showed great nucleation, which made the composite PCM has excellent thermal stability. In conclusion, the prepared C5H7COOK solution containing 5 g/L KCl composite PCM can be acted as a potential material for the refrigeration of agricultural products due to the appropriate and acceptable thermal properties, reliable thermal stability, and high thermal conductivity.

refrigeration; phase change materials; thermodynamic properties; stability

10.11975/j.issn.1002-6819.2018.18.034

TM306

A

1002-6819(2018)-18-0277-07

2018-05-28

2018-08-17

國(guó)家重點(diǎn)研發(fā)項(xiàng)目計(jì)劃（2018YFD0401300）；國(guó)家自然科學(xué)基金（51376115）；上海市科委項(xiàng)目（16040501600）

章學(xué)來(lái)，教授，博導(dǎo)，研究方向?yàn)橄嘧儍?chǔ)能技術(shù)。

Email：xlzhang@shmtu.edu.cn

章學(xué)來(lái)，王迎輝，紀(jì) 珺，劉俊名，李玉洋, 韓興超，徐笑鋒，周孫希，劉 璐，劉 升. 山梨酸鉀/氯化鉀復(fù)合相變材料制備及熱物性分析[J]. 農(nóng)業(yè)工程學(xué)報(bào)，2018，34(18)：277－283. doi：10.11975/j.issn.1002-6819.2018.18.034 http://www.tcsae.org

Zhang Xuelai, Wang Yinghui, Ji Jun, Liu Junming, Li Yuyang, Han Xingchao, Xu Xiaofeng, Zhou Sunxi, Liu Lu, Liu Sheng.Preparation and thermal performance analysis of C5H7COOK/KCl composite phase change material[J]. Transactions of the Chinese Society of Agricultural Engineering (Transactions of the CSAE), 2018, 34(18): 277－283. (in Chinese with English abstract) doi：10.11975/j.issn.1002-6819.2018.18.034 http://www.tcsae.org