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61.
CCl2(A1B1)被O2及取代甲烷类分子猝灭的动力学研究 总被引:2,自引:0,他引:2
对CCl4/Ar混合气体放电产生CCl2自由基,再用541.52nm激光将电子基态CCl2激发到激发态A^1B1(0,4,0)振动态k=0能级上,通过检测 激发态CCl2时间分辨荧光信号,测得室温下CCl2(A^1B1)被O2,CF4,CF2Cl,CH3NO2,CH2Br2等分子猝灭的实验结果,用改进的三能级模型分析处理实验数据,获得态分辨速常数KA和Ka值,并对实验结果进行了讨论。 相似文献
62.
TheBeckInannrearrangement,theacid-mediatedisomerizationofoximestoamides,wasfirstdiscoveredinl886l.Asoneoftheoldestandmostfamiliartransformationsinorganicchemistry,ithasbeenwidelystudiedandagreatvarietyofmethodstoconductthistfansformationhavebeenreported'.However,mostofthesemethodswerecarriedoutbyusingalargeamountofsolventswithlongreactiontime.Whatismore,thepriorpreparationofthecorrespondingketoximesisusuallyrequired,whichmakestheseprocessesinconvenientandlessattractive.Bytakingadvantageofboth… 相似文献
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65.
Pt3Co核-Pt壳型纳米粒子的制备及磁性 总被引:1,自引:1,他引:1
Pt3Co alloy nanoparticles were prepared by the reduction of H2PtCl6 and Co(OOCCH3)2 using NaBH4 as a reducing agent. The Pt3Co core-Pt shell nanoparticles (Pt3Co@Pt) were synthesized using hydrogen absorption reduction and characterized by plasma-atomic emission spectrometry (ICP), transmission electron microscopy (TEM), X-ray diffraction (XRD) and SQUID magnetometer. The results show that average size of Pt3Co@Pt nanoparticles is 3.6 nm with a standard deviation of 0.9 nm. Heating Pt3Co nanoparticles in air at 700 ℃ for 1 h, Co in Pt3Co nanoparticles was oxidized to Co3O4 and CoO; while no oxidation tendency was detected for Pt3Co@Pt nanoparticles. The crystallize structure of Pt3Co@Pt changed from the face centered cube (fcc) to the face centered tetragonal (fct) after the heating treatment. The coercivity of the heated Pt3Co@Pt reached to 276 Oe at room temperature. 相似文献
66.
研究了MMA-St在氧化还原引发剂KPS-CuSO_4-Na_2SO_3存在下的快速无皂乳液聚合.当[MMA]=0.51mol/L、[St]=0.49 mol/L、70℃对,在[KPS]=2.77×10~(-3)mol/L、[CuSO_4]=1.50×10~(-5)mol/L、[Na_2SO_3]=2.77×10~(-3) mol/L条件下反应100min,转化率大于90%;讨论了胶乳的分子量及其分布;求出了聚合反应活化能E_a=81.6 kJ/mol和聚合反应速率常数k_p=321.9 L/mol·s. 相似文献
67.
The influence of additives such as sodium salicylate and sodium chloride on the water solubilization capacity of AOT in n-pentanol solutions has been investigated. The water solubilization capacity is enhanced by sodium salicylate and decreased by sodium chloride. The percolation behavior of the water/AOT/n-pentanol system is studied by modifying the water concentration and temperature. No percolation threshold induced by water or temperature is detected either in the absence or in the presence of additives. The values of ln sigma have a linear correlation with temperature in the range of 5-40 degrees C. The activation energy is also estimated and discussed. 相似文献
68.
Yuming Dong Yuqiang Ding Weifu Dong Cheng Yang Xuefeng Liu Ye Fan Jing Wang Qingwei Pan 《大学化学》1986,35(10):71-76
Based on the development prospect of cosmetics industry, the advantage of light industry characteristic and the foundation of applied chemistry in Jiangnan University, a systematic upgrading of applied chemistry was carried out through "emerging engineering education (3E)" project "upgrade and practice of chemistry-related majors of local and/or trade university responding to the social developments" supported by the Ministry of Education. On the basis of investigation and analysis, the orientation and training goal of applied chemistry were updated first, and then the curriculum system was determined and the curriculum construction is strengthened, so as to achieve more distinctive characteristics, more solid foundation and more comprehensive quality. In view of the new requirements of the 3E for talent training, some practices have been formed in the aspects of multi-disciplinary integration, multi-angle coordination and close integration to industry. Contributing the development of cosmetics industry and seizing the commanding point of science and technology from the perspective of talent training, will play a unique role in human social progress. 相似文献
69.
3-(2-羟基苯基)-5-苯基-6-乙氧羰基-2-环己烯酮的合成与晶体结构 总被引:3,自引:0,他引:3
合成了3-(2-羟基苯基)-5-苯基-6-乙氧羰基-2-环己烯酮.通过元素分析、红外光谱、紫外光谱、核磁共振氢谱和质谱对其组成和结构进行了表征.利用X射线衍射分析方法测定了它的晶体结构.该化合物的晶体属单斜晶系,空间群P21/c,a=1.41946(17)nm,b=0.58445(7)nm,c=2.1756(3)nm,β=104.795(2)°,V=1.7450(4)nm3,Z=4,Dc=1.280 g·cm-3,F(000)=712,μ=0.088mm-1,R1[I>2σ(I)]=0.0627,wR2[I>2σ(I)]=0.1484.晶体结构测定结果表明化合物分子中的环己烯部分为半椅式构象,分子间通过氢键形成具有16元环的二聚体. 相似文献
70.
The enzymatic nitration of phenol and m-cresol catalyzed by horseradish peroxidase was studied in the presence of H2O2 and NaNO2. The results showed that the nitration products of phenol were 2-nitro and 4-nitrophenols. There was also a small amount of by-products of hydroquinone and catechol. The influences of various reaction parameters, including pH, organic solvent type, and concentrations of NaNO2 and H2O2, on the nitration products were investigated. The yields of 4-nitrophenol and 2-nitrophenol were 14% and 12%, respectively. The nitration products of m-cresol were 4-nitro-m-cresol and 6-nitro-m-cresol, and the yields of 4-nitro-m-cresol and 6-nitro-m-cresol were 19% and 30%, respectively. 相似文献