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水解動力學

水解動力學的相關文獻在1989年到2022年內(nèi)共計99篇,主要集中在化學、化學工業(yè)、輕工業(yè)、手工業(yè) 等領域,其中期刊論文77篇、會議論文19篇、專利文獻175699篇;相關期刊61種,包括廣東海洋大學學報、中國藥學雜志、農(nóng)業(yè)環(huán)境科學學報等; 相關會議19種,包括第十三屆全國有機分子電化學與工業(yè)學術會議、第四屆中國膜科學與技術報告會、中國化工學會農(nóng)藥專業(yè)委員會第十四屆年會等;水解動力學的相關文獻由301位作者貢獻,包括梁國剛、梁曜華、歐曉明等。

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水解動力學—發(fā)文趨勢圖

水解動力學

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  • 梁國剛
  • 梁曜華
  • 歐曉明
  • 畢葳
  • 裴暉
  • 雷滿香
  • 任競
  • 劉永剛
  • 張毅
  • 王海軍
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    • 石娟; 包鴻慧; 張佩; 張倜培; 周睿
    • 摘要: 目的:評價全蕓豆食品的生理功效,開發(fā)不同花色蕓豆功能性資源。方法:采用體外胃腸模擬消化模型,分析蕓豆消化液總酚、總黃酮和酸性多糖含量、抗氧化活性與α-淀粉酶抑制活性,以及其淀粉水解動力學與葡萄糖擴散性。結(jié)果:總酚、總黃酮和酸性多糖含量、抗氧化能力及α-淀粉酶抑制能力為黑蕓豆>紅蕓豆>白蕓豆(P<0.05)。淀粉水解一級反應動力學速率、快速消化淀粉含量及消化液葡萄糖擴散速率為黑蕓豆<紅蕓豆<白蕓豆(P<0.05),且蕓豆消化液活性組分含量與抗氧化活性呈顯著正相關(P<0.05),與葡萄糖擴散速率呈顯著負相關(P<0.05)。結(jié)論:蕓豆消化液中富含酚類化合物與酸性多糖,具有良好的抗氧化活性與一定的α-淀粉酶抑制活性。
    • 楊曉云; 江騰輝; 黃其亮; 徐漢虹
    • 摘要: [目的]系統(tǒng)研究印楝素在水溶液中的水解.[方法]硅膠柱層析法和半制備液相色譜法分離純化w為44.56%的印楝素原藥中的印楝素A,采用核磁共振儀和高效液相色譜定性、定量測定分離得到的印楝素A,建立一種檢測水樣中印楝素殘留的高效液相色譜方法.[結(jié)果]核磁共振儀和高效液相色譜測得印楝素A的質(zhì)量分數(shù)分別為90.37%和91.82%.當印楝素添加水平為0.1、1.0和5.0 mg·kg-1時,水樣中印楝素的平均回收率為92.53%~94.12%,變異系數(shù)為0.35%~0.84%,最小檢測質(zhì)量濃度為0.012 mg·L-1.印楝素在pH 4.0~6.0的緩沖溶液中穩(wěn)定,當pH大于8.0時,印楝素降解加快,降解半衰期從pH 8.0的14.856 h 降到pH 10.0的0.033 h.在pH 6.0的緩沖溶液中,25、35、45 °C條件下印楝素的降解半衰期分別為24.68、13.69和2.36 d,而在pH 7.0的緩沖溶液中印楝素的降解半衰期分別為9.35、6.51和0.94 d.在pH 2.0的緩沖溶液中分離純化水解產(chǎn)物得到印楝素A內(nèi)酯衍生物.[結(jié)論]印楝素在堿性環(huán)境下極不穩(wěn)定,而在弱酸性環(huán)境中比較穩(wěn)定.溫度對印楝素的降解影響很大,隨著溫度的升高印楝素降解加快.%[Objective] To study hydrolysis of azadirachtin in water systematically.[Method]Azadirachtin A from the 44.56% azadirachtin TC was isolated and purified by silica column chromatography and semi-preparative high performance liquid chromatography (HPLC).The chemical structure and content of isolated azadirachtin A were identified by nulear magnetic resonance (NMR) and HPLC.A method for determining azaditachtin residue in water by HPLC was established.[Result]The mass fractions of azadirachtin A were 90.37% and 91.82% detected by NMR and HPLC respectively.When azadirachtin was added with the concentrations of 0.1, 1.0 and 5.0 mg·kg-1, the average recovery rates of azadirachtin from water samples ranged from 92.53% to 94.12%, the variation coefficients ranged from 0.35% to 0.84%, and the minimum detection limit was 0.012 mg·L-1.Azadirachtin was stable in buffer solutions with pH varying from 4.0 to 6.0.When pH was above 8.0, hydrolysis of azadirachtin was accelerated, and the degradation half-life was 14.856 h at pH 8.0 and declined to 0.033 h at pH 10.0.The degration half-lives of azadirachtin in buffer solutions at pH 6.0 were 24.68, 13.69 and 2.36 d under 25, 35 and 45 °C temperature respectively, while were 9.35, 6.51 and 0.94 d at pH 7.0.A lactone derivative of azadirachtin was obtained by isolating and purifing hydrolysate in buffer solution at pH 2.0.[Conclusion]Azadirachtin is extremely unstable in alkaline environment while relatively stable in weak acid environment.Temperature has a great effect on the degradation of azadirachtin and the degradation accelerates as temperature increases.
    • 于秀穎; 李紅亮; 朱瑋; 王萬朋; 張琳
    • 摘要: OBJECTIVE To explore the hydrolysis kinetics of capilliposide B and capilliposide C under different temperatures and pH values,and identify the hydrolysis products.METHODS The LC-B and LC-C were quantified by HPLC,then the hydrolysis process was deduced.Samples were taken to investigate the stability of LC-C and LC-B at different time points under the conditions of 30,50,70 °C,and pH 8.0,9.0,10.0,11.0,respectively.The hydrolysis products were identified by mass spectrometry and nuclear magnetic resonance spectroscopy.RESULTS The hydrolysis reaction rates of LC-B and LC-C obeyed first-order kinetics under different pH values and temperatures.And they were related to hydrolysis temperature and pH:at the same temperature,the higher the pH,the faster the hydrolysis rate;at the same pH,the higher the temperature,the faster the hydrolysis rate.The hydrolysis product was capilliposide A.CONCLUSION The study provided an effective method for the preparation of LC-A.%目的 研究細梗香草皂苷B(capilliposide B,LC-B)和細梗香草皂苷C(capilliposide C,LC-C)在不同溫度,pH條件下水解動力學,及水解產(chǎn)物的鑒定.方法 采用高效液相色譜法測定LC-B,LC-C含量,推導出LC-B,LC-C水解過程,恒溫30,50和70°C,pH分別為9.0,10.0,11.0的條件下,不同時間點分別取樣檢測LC-C和LC-B的含量,探討其穩(wěn)定性,并通過質(zhì)譜、核磁共振譜鑒定水解產(chǎn)物.結(jié)果 LC-B,LC-C在不同溫度,pH條件下的水解反應均符合一級動力學.水解速率受水解的溫度和體系pH值的影響:相同的水解溫度,pH越高,水解越快;相同pH,溫度越高水解越迅速.水解產(chǎn)物為細梗香草皂苷A(capilli-poside A,LC-A).結(jié)論 該實驗為LC-A的制備提供一種有效方法.
    • 徐艷; 楊廣存; 李振花; 趙玉軍; 馬新賓
    • 摘要: 針對Amberlyst-15樹脂為催化劑的草酸二乙酯水解過程進行了研究,考察了催化劑用量、水酯比及溫度對反應的影響.結(jié)果表明Amberlyst-15的加入能明顯提高水解速率.草酸二乙酯水解反應為連串反應,草酸單乙酯為中間產(chǎn)物.基于樹脂催化反應特點提出了包含離子交換樹脂催化作用和水解產(chǎn)生的草酸的催化作用在內(nèi)的動力學模型.通過實驗數(shù)據(jù)的回歸獲得動力學參數(shù),模型計算與實驗數(shù)據(jù)的平均相對偏差<0.06,表明該模型適用于草酸二乙酯樹脂催化水解動力學規(guī)律的描述.
    • 吳亞; 李凡; 徐甜莉; 陳剛; 薛丹; 史俊
    • 摘要: 以BrΦnsted酸硼酸作為催化劑高效地合成了固體酯水楊酸苯酯和苯甲酸苯酯,并利用液體法IR研究其水解動力學.通過IR,GC-MS等進行結(jié)構(gòu)表征,并優(yōu)化反應條件:n(羧酸)∶n(苯酚)∶n(硼酸)為1.5∶ 1∶0.2,135°C回流24 h,水楊酸苯酯和苯甲酸苯酯產(chǎn)率分別達86%和61%.利用液體法IR監(jiān)測酯的水解,依據(jù)IR中1 650 cm-1 ~1 800cm-1的特征吸收峰強度變化,獲得不同pH、溫度時固體酯水解動力學.該研究提供一種簡便高效的合成固體酯的方法,并闡明了固體酯水解的影響因素及規(guī)律.
    • 呂陽成; 王蕊; 張吉松; 靳倩如; 駱廣生
    • 摘要: Synthesizing epichlorohydrin(ECH) from dichloropropanol(DCP) is a complicated reaction due to the partial decomposition of ECH under harsh conditions. A microchemical system can provide a feasible platform for improving this process by conducting a separation once full conversion has been achieved. In this work, referring to a common DCP feed used in industry, the reaction performance of mixed DCP isomers with Na OH in the microchemical system on various time scales was investigated. The operating window for achieving high conversion and selectivity was on a time scale of seconds, while the side reactions normally occurred on a time scale of minutes. Plenty of Cl-ions together with a high temperature were proved to be critical factors for ECH hydrolysis.A kinetic study of alkaline mediated ECH hydrolysis was performed and the requirements for an improved ECH synthesis were proposed by combining quantitative analysis using a simpli fied reaction model with experimental results on the time scale of minutes. Compared with the conventional distillation process, this new strategy for ECH synthesis exploited microchemical system and decoupled the reaction and separation with potentials of higher productivity and better reliability in scaling up.
    • 繆華麗; 劉今強; 李永強; 付承臣; 張玉高
    • 摘要: 采用HPLC研究活性染料/D5懸浮體系染色過程中染料的水解性能,以明確該體系所實現(xiàn)的超低浴比染色環(huán)境是否有效抑制染料水解從而獲得更高固著率的機制.通過模擬D5染色和傳統(tǒng)水浴染色的染料水解環(huán)境,研究了不同環(huán)境下C.I活性紅195在pH值為11、60 ~ 80°C條件下的水解情況.結(jié)果表明:活性染料/D5懸浮體系染色過程中極少水量的染色環(huán)境顯著抑制了染料水解,pH值為11條件下水解90 min,D5介質(zhì)中雙水解染料量相對傳統(tǒng)水浴60°C減小27.8%,70°C減小57.8%,80°C減少51.1%.相同溫度下,傳統(tǒng)水浴中染料的水解速率是D5介質(zhì)中的1.8倍左右.同時,一定量織物的存在可進一步降低D5介質(zhì)染色的模擬水解條件下雙水解染料的量,水解速率常數(shù)也有所降低.%Hydrolysis kinetics of reactive dye in dye/D5 suspending system was investigated using HPLC to see whether the super low bath ratio dyeing realized by this system had effectively inhibited dye hydrolysis and thus obtained a higher fixation ratio.HPLC analysis of dye hydrolysis kinetics was carried out using C.I.Reactive Red 195 under the simulated hydrolysis conditions at pH =11,and temperature 60 ~ 80 °C.The results showed that hydrolysis of dye in dye/D5 suspending system was much lower than that in aqueous system.The amount of complete hydrolyzed dye after 90 min treatment in the dye/D5 suspending system under simulated conditions at pH =11 was reduced by 27.8% at 60 °C,57.8% at 70 °C and 51.1% at 80 °C,respectively,as compared with the conventional aqueous system.And when the temperature was identical,the hydrolysis rate in aqueous system was 1.8 times of that in the dye/D5 system.When hydrolysis performed in the presence of fabric in dye/D5 suspending system,the amount of complete hydrolyzed dye was further reduced,and so did the rate constants.
    • 王專; 謝亞杰; 徐松; 胡萬鵬; 王俊秋; 金梅梅
    • 摘要: 為考察均三嗪和乙烯砜的雙活性基團活性染料的耐堿性,以活性黃176為例,采用反相離子對高效液相色譜法,測定了一系列活性黃176的濃度隨時間、溫度、pH值等變化的實驗數(shù)據(jù),得出了活性黃176在不同條件下的水解關系曲線,并采用準一級反應動力學模型擬合實驗數(shù)據(jù).結(jié)果表明:在酸性介質(zhì)(pH 4.47)中,雙活性基團染料活性黃176會水解,但溫度升高時變化規(guī)律不明顯;在中性介質(zhì)(pH8.07)中,溫度越高染料水解速度越快.并且兩者在溫度一定時染料水解反應基本服從準一級反應(R2>0.982).在堿性介質(zhì)(pH10.3)中,溫度升高活性黃176水解十分劇烈,并幾乎嚴格按照準一級反應進行(R2>0.992).
    • 鄒梅娟; 王晶; 陳洪濤; 盧方正
    • 摘要: 目的考察吲哚美辛5-氟尿嘧啶甲酯(indom ethacin5-fluorouracil-1-ylmethyl ester,IFM)水溶液在不同pH值、不同溫度及在Krebs-Ringer試液中的化學穩(wěn)定性。方法采用經(jīng)典恒溫法測定IFM在不同條件下的降解情況。結(jié)果 IFM在水溶液中的降解速率常數(shù)與溶液pH值和溫度有關。隨著溫度的升高,IFM的降解速度加快;pH值在3.6~5.8內(nèi)穩(wěn)定性較好,pH小于2.0或大于6.8時,隨溫度升高,降解明顯加快。但在室溫和310K條件下較穩(wěn)定。310K下IFM在Krebs-Ringer試液中的降解速率常數(shù)為9.0×10-4h-1。結(jié)論 IFM在水溶液中的降解符合一級反應動力學特點,IFM在水溶液中的降解為酸堿催化反應。
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