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1.
本文设计合成了两种以聚吡唑硼酸盐、吡唑为配体的铜配合物Cu2[ μ-pz]2[HB(pz)3]2(1)和Cu[B(pz)4]2(2)(pz:吡唑(C3H4N2))。运用元素分析、红外光谱对配合物进行了表征,并用X-ray衍射测定了它们的晶体结构。非等温热分解动力学研究表明:配合物1的热分解反应分两步,配合物2的热分解反应一步进行。通过计算,配合物1热分解的第一步反应的可能机理为成核与生长,n=1/4;第二步反应的可能机理为化学反应。其非等温动力学方程分别为:dα/dT=A/β e-E/RT·1/4(1-α)[-ln(1-α)]-3和dα/dT=A/β e-E/RT·(1-α)2。分解反应的表观活化能分别是520.37 kJ·mol-1和149.65 kJ·mol-1;指前因子lnA分别是118.06 s-1和28.10 s-1。配合物2热分解的可能机理为化学反应。其非等温动力学方程为:dα/dT=A/β e-E/RT·(1-α)2。分解反应的表观活化能是111.41 kJ·mol-1;指前因子lnA是21.20 s-1。  相似文献   

2.
合成了高氯酸镨和咪唑(C3H4N2), DL-α-丙氨酸(C3H7NO2)混配配合物晶体. 经傅立叶变换红外光谱、化学分析和元素分析确定其组成为[Pr(C3H7NO2)2(C3H4N2)(H2O)](ClO4)3. 使用具有恒温环境的溶解-反应量热计, 以2.0 mol•L-1 HCl为量热溶剂, 在T=(298.150±0.001) K时测定出化学反应PrCl3•6H2O(s)+2C3H7NO2(s)+C3H4N2(s)+3NaClO4(s)=[Pr(C3H7NO2)2(C3H4N2)(H2O)](ClO4)3(s)+3NaCl(s)+5H2O(1)的标准摩尔反应焓为ΔrHmө=(39.26±0.11) kJ•mol-1. 根据盖斯定律, 计算出配合物的标准摩尔生成焓为ΔfHmө{[Pr(C3H7NO2)2(C3H4N2)(H2O)](ClO4)3(s), 298.150 K}=(-2424.2±3.3) kJ•mol-1. 采用TG-DTG技术研究了配合物在流动高纯氮气(99.99%)气氛中的非等温热分解动力学, 运用微分法(Achar-Brindley-sharp和Kissinger法)和积分法(Satava-Sestak和Coats-Redfern法)对非等温动力学数据进行分析, 求得分解反应的表观活化能E=108.9 kJ•mol-1, 动力学方程式为dα/dt=2(5.90×108/3)(1-α)[-ln(1-α)]-1exp(-108.9×103/RT).  相似文献   

3.
合成了高氯酸镨和咪唑(C3H4N2), DL-α-丙氨酸(C3H7NO2)混配配合物晶体. 经傅立叶变换红外光谱、化学分析和元素分析确定其组成为[Pr(C3H7NO2)2(C3H4N2)(H2O)](ClO4)3. 使用具有恒温环境的溶解-反应量热计, 以2.0 mol•L-1 HCl为量热溶剂, 在T=(298.150±0.001) K时测定出化学反应PrCl3•6H2O(s)+2C3H7NO2(s)+C3H4N2(s)+3NaClO4(s)=[Pr(C3H7NO2)2(C3H4N2)(H2O)](ClO4)3(s)+3NaCl(s)+5H2O(1)的标准摩尔反应焓为ΔrHmө=(39.26±0.11) kJ•mol-1. 根据盖斯定律, 计算出配合物的标准摩尔生成焓为ΔfHmө{[Pr(C3H7NO2)2(C3H4N2)(H2O)](ClO4)3(s), 298.150 K}=(-2424.2±3.3) kJ•mol-1. 采用TG-DTG技术研究了配合物在流动高纯氮气(99.99%)气氛中的非等温热分解动力学, 运用微分法(Achar-Brindley-sharp和Kissinger法)和积分法(Satava-Sestak和Coats-Redfern法)对非等温动力学数据进行分析, 求得分解反应的表观活化能E=108.9 kJ•mol-1, 动力学方程式为dα/dt=2(5.90×108/3)(1-α)[-ln(1-α)]-1exp(-108.9×103/RT).  相似文献   

4.
[La(CH2ClCOO)2(NO3)(phen)(H2O)]n的合成和晶体结构   总被引:5,自引:0,他引:5  
合成了混合阴离子配合物[La(CH2ClCOO)2(NO3)(phen)(H2O)]n。配合物经元素分析、IR、DTA-TG和UV等表征。用X射线单晶结构分析解析了标题配合物的晶体结构,三斜,空间群P1,晶胞参数为a=10.533(2)?,b=13.136(3)?,c=7.776(1)?,α=96.59(1)°,β=95.76(1)°,γ=108.42(2)°,V=1003.3(3)?3,Z=2,Dc=1.940 g/cm3, F(000)=572, μ(Mo Kα)=24.36 cm-1。  相似文献   

5.
合成了2个新的希土冠醚配合物Ln(NO3)3·C26H38N2O4(Ln=La、Ce; C26H38N2O4=1, 7, 10, 16-四氧-4,13-二氮杂-N,N′-二苄基环十八烷)。通过元素分析,红外光谱,拉曼光谱及其 1H核磁共振谱进行表征。用四圆衍射仪测定了La(NO3)3·C26H38N2O4·CH3CN的晶体结构。晶体属三斜晶系,P1空间群,晶胞参数:a=1.2869(4) nm, b=1.5868(6) nm, c=0.9147(2) nm; α=101.89(2)°, β=105.38(2)°, γ=71.96(3)°; Z=2。dcald.=1.58 g·cm-3, μ(Mo)=13.25 cm-1。中心镧离子与冠醚配体中的4个氧原子和2个氮原子配位,3个硝酸根中的6个氧原子也与La3+配位,形成配位数为12的配合物。  相似文献   

6.
在无水乙醇中, 使低水合氯化稀土 (RE = Ho, Er, Tm, Yb, Lu) 与吡咯烷二硫代氨基甲酸铵 (APDC)和1,10-菲咯啉 (o–phen•H2O) 反应, 制得其三元固态配合物. 用化学分析和元素分析确定它的组成为RE(C5H8NS2)3(C12H8N2) (RE = Ho, Er, Tm, Yb, Lu). IR光谱说明RE3+ 分别与3个PDC的6个硫原子双齿配位, 同时与o–phen的2个氮原子双齿配位, 配位数为8. 用精密转动弹热量计测定了它们的恒容燃烧热△cU分别为(-16788.46 ± 7.74), (-15434.53 ± 8.28), (-15287.80 ± 7.31), (-15200.50 ± 7.22)和(-15254.34 ± 6.61) kJ•mol-1; 并计算了它们的标准摩尔燃烧焓△cHmθ和标准摩尔生成焓△fHmθ分别为( -16803.95 ± 7.74), (-15450.02 ± 8.28), (-15303.29 ± 9.28), (-15215.99 ± 7.22), (-15269.83 ± 6.61) kJ • mol-1和 (-1115.42 ± 8.94), (-2477.80 ± 9.15), (-2619.95 ± 10.44), (-2670.17 ± 8.22), (-2650.06 ± 8.49) kJ•mol-1.  相似文献   

7.
通过溶剂热法合成了2种三维微孔锌金属有机框架材料,其分子式为[Zn3(DBA)(OH)(1,10-phen)2]n(1)和{[Zn2(HDBA)(4,4''-bipy)1.5]·H2O}n(2)(H5DBA=3,5-二(2'',4''-对羧基苯基)苯甲酸;1,10-phen=1,10-菲咯啉;4,4''-bipy=4,4''-联吡啶)。结构分析表明,配合物1为三核锌基金属单元的三维微孔骨架,配合物2为双核锌基的微孔结构。与2相比,配合物1在水中具有较强的发光性能,可作为检测Fe3+、Cr2O72-和丙酮分子的发光传感器,具有较高的选择性和灵敏度。  相似文献   

8.
武望婷  胡怀明  王尧宇  史启祯 《化学学报》2005,63(22):2032-2036
在水-乙醇混合体系中, 以2-羰基丙酸水杨酰腙(C10H10N2O4)、2,2-联吡啶(C10H8N2, 简写bipy)与Eu(NO3)3•4H2O反应, 首次培养出黄色单晶[Eu(C10H9N2O4)(C10H8N2O4)(H2O)3]•0.5bipy•3H2O. 该晶体属三斜晶系, 空间群为P-1, 晶胞参数a=0.93392(16) nm, b=1.3100(2) nm, c=1.3895(2) nm, α=97.205(3)°, β=105.411(2)°, γ=106.364(2)°, V=15.35(2) nm3, Z=2, μ=2.118 mm-1, Dc=1.686 Mg/m3, F(000)=786, R=0.0116, wR=0.0507, GOF=0.995. 晶体测试结果表明, 该单晶结构为铕的9配位配合物, 两个2-羰基丙酸水杨酰腙分别以负一价和负二价酮式和三个水分子同时参与配位; 每个2-羰基丙酸水杨酰腙中的羧基氧、酰胺基中的羰基氧和C=N中的氮与Eu3+配位, 形成两个共边的稳定五元环, 另三个配位原子则分别来自三个水分子中的氧原子, 该配合物在空间呈扭曲的单帽四方反棱柱, 而在不对称单位中还有游离的一个2,2-联吡啶分子和三个水分子, 这些游离分子与配位分子之间存在大量分子内和分子间氢键, 整个分子在空间呈三维网状结构. 发光性能测试表明该配合物具有很好的荧光性质.  相似文献   

9.
齐斌  晁余涛 《化学学报》2007,65(19):2117-2123
在6-311+G(2d,2p)水平下, 采用密度泛函理论(DFT)的B3LYP方法, 研究了Criegee 自由基CH2O2与H2O的反应. 结果表明反应存在三个通道: CH2O2+H2O®HOCH2OOH (R1); CH2O2+H2O®HCO+OH+H2O (R2); CH2O2+H2O®HCHO+H2O2 (R3), 各通道的势垒高度分别为43.35, 85.30和125.85 kJ/mol. 298 K下主反应通道(R1)的经典过渡态理论(TST)与变分过渡态理论(CVT)的速率常数kTSTkCVT均为2.47×10-17 cm3•molecule-1•s-1, 而经小曲率隧道效应模型(SCT)校正后的速率常数kCVT/SCT 5.22×10-17 cm3•molecule-1•s-1. 另外, 还给出了200~2000 K 温度范围内拟合得到的速率常数随温度变化的三参数Arrhenius方程.  相似文献   

10.
钌可以促使炔烃通过亚乙烯基钌卡宾金属配合物或钌金属杂环配合物的形式发生碳-碳偶联反应, 它的化学性质很大程度上取决于配体的电子和立体特征. 普通环戊二烯基钌配合物可以促使炔烃三聚生成苯环衍生物或使两分子炔烃和一分子含C=X键(X = C, O, S, N等)的不饱和底物发生环加成反应得到杂环化合物. 含桥联碳硼烷–环戊二烯基配体的钌乙腈配合物[η5:σ-Me2C(C5H4)(C2B10H10)]Ru(NCCH3)2 (1)表现出与环戊二烯基钌不同的反应性质. 例如, 配合物1与三甲基硅基取代的端炔或中间炔反应可生成含有单或双亚乙烯基有机钌卡宾配合物; 与末端芳炔则通过三分子炔和桥联配体中的环戊二烯基发生加成反应得到含有独特三环结构的有机钌配合物. 以上结果表明, 配体的位阻效应和炔烃的种类都可以影响产物的类型. 本文进一步研究了此钌乙腈配合物1与烷基或芳基取代的中间炔及中间二炔的反应. 配合物1与3-己炔或二苯乙炔在甲苯中于 80 ℃反应可以生成对空气和水稳定的η4-钌-环丁二烯配合物[η5: σ-Me2C(C5H4)(C2B10H10)]Ru(η4-C4Et4) (2) 或 [η5:σ-Me2C(C5H4)(C2B10H10)]Ru(η4-C4Ph4) (3), 此反应相信是通过一个钌杂环戊三烯中间体进行的. 由于这个中间体既不能在反应中被分离到也不能在核磁反应中被监测到, 我们接下来尝试了1和1,6-二炔的反应. 在 1与2,7-壬二炔或3,8-十一碳二炔的反应中成功分离到钌杂环戊三烯配合物[η5: σ-Me2C(C5H4)(C2B10H10)]Ru[=C2- (Me)2C2(CH2)3] (4) 或 [η5: σ-Me2C(C5H4)(C2B10H10)]Ru[=C2(Et)2C2(CH2)3] (5). 化合物4与5 在甲苯回流温度仍然稳定. 由于位阻效应, 它们也不与苯乙炔、3-己炔、苯基异氰酸酯、二硫化碳以及叔丁基异腈反应. 以上新化合物通过了核磁和元素分析表征, 其中化合物2和4的结构得到了单晶X射线衍射确定. 在化合物2的晶体结构中, 钌原子通过η5-键与环戊二烯基配位, σ-键与硼笼相连, 以及η4-键与环丁二烯配位, 形成一个平面三角形结构. 在化合物4的晶体结构中, 钌原子通过η5-键与环戊二烯基配位, σ-键与硼笼相连, 以及与两个碳卡宾原子配位, 形成一个扭曲四面体构型. 钌与碳卡宾原子之间的键长显示其为Ru=C双键. 在以上实验结果基础上我们提出了1与炔烃反应生成2和3的反应机理: 钌-乙腈配合物通过与炔烃的配体交换反应得到钌-二炔配合物, 进一步氧化偶联得到钌杂环戊三烯中间体, 还原消除反应得到最终产物?钌-环丁二烯配合物. 在1与二炔的反应中, 4和5中的并环结构可以阻止还原消除反应, 从而起到稳定钌杂环戊三烯中间体的作用. 上述实验结果表明, 桥联碳硼烷配体和底物(炔烃)的空间位阻效应都对反应有很大的影响.  相似文献   

11.
The solid-state ternary complex of terbium chloride with L-tyrosine and glycine, [Tb(Tyr)(Gly)3Cl3·3H2O], was synthesized and characterized. Using a solution-reaction isoperibol calorimeter, the enthalpy of reaction for the following reaction, TbCl3·6H2O(s)+Tyr(s)+3Gly(s)=Tb(Tyr)(Gly)3Cl3·3H2O(s)+3H2O(l), was determined to be (5.1±0.6) kJ mol-1. The standard enthalpy of formation of Tb(Tyr)(Gly)3Cl3-3H2O at T=298.15 K has been derived as -(4267.3±2.3) kJ mol-1. The thermal decomposition kinetics of the complex was studied by non-isothermal thermogravimetry in the temperature range of 325-675 K. Two main mass loss stages existed in the process of the decomposition of the complex, the kinetic parameters for the second stage were analyzed by means of differential and integral methods, respectively. Comparing the results of differential and integral methods, mechanism functions of the thermal decomposition reaction for its second stage were proposed. The kinetic equation can be expressed as: d/dt=Aexp(-E/RT)(1-)2. The average values of the apparent activation energy E and pre-exponential factor A were 213.18 kJ mol-1 and 2.51·1020 s-1, respectively.  相似文献   

12.
汪敦佳  方正东  魏先红 《中国化学》2005,23(12):1600-1606
A new polyoxometalate (CPFX·HCl)3H4SiW12O40·10H2O was prepared from ciprofloxacin hydrochloride and H4SiW12O40·nH2O in aqueous solution, and characterized by elemental analysis, IR spectra and DTA-TG-DTG techniques. The IR spectrum confirmed the presence of Keggin structure and the characteristic functional group for ciprofloxacin in the compound. The TG-DTA-DTG curves showed that its thermal decomposition was a four-step process consisting of simultaneous collapse of Keggin type structure. The residue of decomposition was the mixture of WO3 and SiO2, confirmed by X-ray diffraction and IR spectroscopy. The decomposition mechanism and nonisothermal kinetic parameters of the polyoxometalate were obtained from an analysis to the TG-DTG curves by the single scanning methods (the Achar method and Coats-Redfern method) and the multiple scanning methods (the Kissinger method, Flynn-Wall-Ozawa method and Starink method). The results indicate that the kinetic equationswith parameters describing the thermal decomposition reaction are dα/dt=6.65×10^6[3(1-α)^2/3]e^-10495.5/T with E=87.26 kJ/mol and A=6.65×10^6 s^-1 for the second step,dα/dt=7.01×10^9(1-α)e^-18770.7/T with E=156.06 kJ/mol and A=7.01×10^9 s^-1 for the third step,dα/dt=9.77×10^43[(1-α)^2]e^-88980.0/T with E=739.78 kJ/mol and A=9.77×10^43 s^-1 for the fourth step.  相似文献   

13.
邻苯二胺与5-氯-2-羟基二苯酮、邻香草醛作用合成了一种不对称希夫碱配体C27H21N2O3Cl(H2L)。在正丁醇和甲醇体系中硝酸铀酰与该配体反应合成了一种固体希夫碱配合物[UO2(HL)(NO3)(H2O)]·H2O。通过元素分析、IR、UV、1H NMR、TG-DTG及摩尔电导率分析等手段对合成的配合物进行了表征,用非等温热重法研究了铀(Ⅵ)配合物的热分解反应动力学,推断出第三步热分解的动力学方程为:d α /d t = A · e- E/RT ·3/2[(1- α )-1/3-1]-1,得到了动力学参数E和A。并计算出了活化熵△S¹和活化吉布斯自由能△G¹。  相似文献   

14.
TG-DTG technique and Harcourt-Esson integrated equation were used to study the dehydration process of zinc phosphate tetrahydrate α-Zn3(PO4)2·4H2O nanoparticle and its thermal decomposition kinetics. The results show that there are three stages of dehydration between 300 and 800 K during the thermal decomposition of α-Zn3(PO4)2·4H2O nanoparticle. The first stage is controlled by chemical reaction with an activation energy of 69.48 kJ·mol^-1 and a pre-exponential factor of 1.77×10^6 s^-1. The second is controlled by nucleation and growth with an activation energy of 78.74 kJ·mol^-1 and a pre-exponential factor of 5.86×10^9 s^-1. The third is controlled by nucleation and growth with an activation energy of 141.5 kJ·mol^-1 and a pre-exponential factor of 1.01×10^12 s^-1. The kinetic compensative effects not only exist in Arrhenius equation but also in Harcourt-Esson equation. Activation energy E is dependent on both the decomposition fraction α and temperature T.  相似文献   

15.
The thermal behavior of 4,6‐bis‐(5‐amino‐3‐nitro‐1,2,4‐triazol‐1‐yl)‐5‐nitropyrimidine (BANTNP) was studied under a non‐isothermal condition by DSC, PDSC and TG/DTG methods. The kinetic parameters (Ea and A) of the exothermic decomposition reaction are 304.52 kJ·mol?1 and 1024.47 s?1 at 0.1 MPa, 272.52 kJ·mol?1 and 1021.76 s?1 at 5.0 MPa, respectively. The kinetic equation at 0.1 MPa can be expressed as: dα/dT=1025.3(1?α)3/4exp(?3.8044×104/T)/β The critical temperature of thermal explosion is 588.28 K. The specific heat capacity of BANTNP was determined with a Micro‐DSC method, and the standard molar specific heat capacity is 397.54 J·mol?1·K?1 at 298.15 K. The adiabatic time‐to‐explosion of BANTNP was calculated to be 11.75 s.  相似文献   

16.
The two complexes, [RE(Gly)4(Im)(H2O)](ClO4)3(s)(RE = Eu, Sm), have been synthesized and characterized. The standard molar enthalpies of reaction for the following reactions, RECl3·6H2O(s)+4Gly(s)+Im(s)+3NaClO4(s) = =[RE(Gly)4(Im)(H2O)](ClO4)3(s)+3NaCl(s)+5H2O(l), were determined by solution-reaction colorimetry. The standard molar enthalpies of formation of the two complexes at T = 298.15 K were derived as Δf H mΘ {Eu(Gly)4(Im)(H2O)}(ClO4)3(s)} = = −(3396.6±2.3) kJ mol−1 and Δf H mΘ {Sm(Gly)4(Im)(H2O)}(ClO4)3(s)} = −(3472.7±2.3) kJ mol−1, respectively.  相似文献   

17.
A new unsymmetrical, solid, Schiff base (H2LLi) was synthesized using L-lysine, o-vanillin and salicylaldehyde. An Er(III) complex of this ligand [Er(H2L)(NO3)](NO3)?·?2H2O was prepared and characterized by elemental analysis, IR, UV and molar conductance. The thermal decomposition kinetics of the complex for the second stage was studied under non-isothermal conditions by TG and DTG methods. The kinetic equation may be expressed as, dα/dt?=?A?·?e?E/RT ?·?1/2(1???α)[?ln(1???α)]?1. The kinetic parameters (E,?A), activation entropy S and activation free-energy G were also determined.  相似文献   

18.
Three novel copper(II) complexes, [Cu(Gly‐l ‐Val)(HPBM)(H2O)]·ClO4·H2O ( 1 ), [Cu(Gly‐l ‐Val)(TBZ)(H2O)]·ClO4 ( 2 ) and [Cu(Gly‐l ‐Val)(PBO)(H2O)]·ClO4 ( 3 ) (Gly‐l ‐Val = glycyl‐l ‐valine anion, HPBM = 5‐methyl‐2‐(2′‐pyridyl)benzimidazole, TBZ = 2‐(4′‐thiazolyl)benzimidazole, PBO = 2‐(2′‐pyridyl)benzoxazole), have been prepared and characterized with elemental analyses, conductivity measurements as well as various spectroscopic techniques. The interactions of these copper complexes with calf thymus DNA were explored using UV–visible, fluorescence, circular dichroism, thermal denaturation, viscosity and docking analyses methods. The experimental results showed that all three complexes could bind to DNA via an intercalative mode. Moreover, the cytotoxic effects were evaluated using the MTT method, and the antimicrobial activity of these complexes was tested against Bacillus subtilis, Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa. The results showed that the activities are consistent with their DNA binding abilities, following the order of 1 > 2 > 3 .  相似文献   

19.
2‐(Dinitromethylene)‐1,3‐diazacycloheptane (DNDH) was prepared by the reaction of 1,1‐diamino‐2,2‐dinitroethylene (FOX‐7) with 1,4‐diaminoethane in NMP. Thermal decomposition behavior of DNDH was studied under the non‐isothermal conditions with DSC method, and presents only one intensely exothermic decomposition process. The kinetic equation of the decomposition reaction is dα/dT=1033.88×3α2/3exp(−3.353×105/RT)/β. The critical temperature of thermal explosion is 215.97°C. Specific heat capacity of DNDH was studied with micro‐DSC method and theoretical calculation method, and the molar heat capacity is 215.40 J·mol−1·K−1 at 298.15 K. Adiabatic time‐to‐explosion was calculated to be 92.07 s. DNDH has same thermal stability to FOX‐7.  相似文献   

20.
Thermal decomposition behavior and non‐isothermal decomposition reaction kinetics of nitrate ester plasticized polyether NEPE propellant containing ammonium dinitramide (ADN), which is one of the most important high energetic materials, were investigated by DSC, TG and DTG at 0.1 MPa. The results show that there are four exothermic peaks on DTG curves and four mass loss stages on TG curves at a heating rate of 2.5 K·min?1 under 0.1 MPa, and nitric ester evaporates and decomposes in the first stage, ADN decomposes in the second stage, nitrocellulose and cyclotrimethylenetrinitramine (RDX) decompose in the third stage, and ammonium perchlorate decomposes in the fourth stage. It was also found that the thermal decomposition processes of the NEPE propellant with ADN mainly have two mass loss stages with an increase in the heating rate, that is the result of the decomposition heats of the first two processes overlap each other and the mass content of ammonium perchlorate is very little which is not displayed in the fourth stage at the heating rate of 5, 10, and 20 K·min?1 probably. It was to be found that the exothermal peak temperatures increased with an increase in the heating rate. The reaction mechanism was random nucleation and then growth, and the process can be classified as chemical reaction. The kinetic equations of the main exothermal decomposition reaction can be expressed as: dα/dt=1012.77(3/2)(1?α)[?ln(1?α)]1/3 e?1.723×104/T. The critical temperatures of the thermal explosion (Tbe and Tbp) obtained from the onset temperature (Te) and the peak temperature (Tp) on the condition of β→0 are 461.41 and 458.02 K, respectively. Activation entropy (ΔS), activation enthalpy (ΔH), and Gibbs free energy (ΔG) of the decomposition reaction are ?7.02 J·mol?1·K?1, 126.19 kJ·mol?1, and 129.31 kJ·mol?1, respectively.  相似文献   

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