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1.
邻苯二甲酸镍配合物的流变相法合成及热分析   总被引:1,自引:0,他引:1  
用流变相反应法合成了四水邻苯二甲酸镍,用TG、DTG、DSC、红外光谱、质谱研究了它在氮气气氛中的热分解机理.邻苯二甲酸镍在氮气气氛中热分解分为三步:第一步四水邻苯二甲酸镍分解为无水盐;第二步无水盐分解为碳酸盐和有机化合物,生成的有机化合物成分比较复杂,主要成分是邻苯二甲酸酐、9,10-蒽醌等;第三步碳酸盐继续分解生成氧化镍和二氧化碳.  相似文献   

2.
用流变相反应法合成2种苯甲酸铝配合物,通过元素分析,红外光谱,TG、DTG和DTA确定了配合物的组成,用TG、DTG、DTAI、R、XRD、FABMS表征了热分解产物并研究了配合物在氮气气氛中的热分解过程.苯甲酸铝在氮气气氛中的热分解分2步进行:第一步失去水分子成为苯甲酸内盐;第二步苯甲酸内盐分解生成氧化铝和有机化合物,生成的有机化合物成分比较复杂,主要成分是9,10-蒽醌等.  相似文献   

3.
苯甲酸锰的合成及热分解机理研究   总被引:5,自引:0,他引:5  
用半固相反应合成了苯甲酸锰,通过元素分析,X-射线粉末衍射,红外光谱确定它的组成和晶体结构,它属单斜晶系,为层状结构,用DTA和TG研究了它在空气和氮气气氛中的热分解过程,并用红外光谱表征了热分解产物。苯甲酸锰在空气中一步分解生成氧化锰,在氮气中除分解生成氧化锰外,生成的气相凝聚物成分比较复杂,主要成分是二苯甲酮和三苯甲烷等。  相似文献   

4.
用流变相反应法合成了水杨酸锰配合物.通过元素分析、TG确定该配合物的组成为Mn(HSal)2·2.5H2O(HSal=o-OHC6H4COO);XRD确定该配合物为单斜晶系,晶胞参数为a=1.8935(4)nm,b=6.1790(2)nm,c=17.3256(1)nm,β=114.93°,V=1.8382(3)nm3,Z=6,Dcalc=1.775kg/dm3,Dexp=1.769kg/dm3;IR研究表明配合物中羧酸根与Mn2+是以双齿螯合方式配位.样品的热分解实验表明该配合物的热分解机理为Mn(HSal)2·2.5H2O90~160℃Mn(HSal)2180~270℃MnSal+H2Sal;MnSal290~335℃MnO+有机化合物.+2.5H2O;Mn(HSal)2  相似文献   

5.
采用双峰双波长分光光度法,在pH9.0的硼砂缓冲介质中,对5-Br-PADAP与锰(Ⅱ)生成的紫红色络合物进行测定.结果表明:试剂和络合物的最大吸收波长分别为440 nm和570nm,锰(Ⅱ)含量在0~10 mg·L-1范围内符合比尔定律.该法ε=1.79×105L·mol-1·cm-1,比单波长法ε=1.04×105L·mol-1·cm-1提高1.72倍,说明该试剂具有较高的灵敏度,用于测定钢样中微量锰得到满意结果.  相似文献   

6.
溶胶凝胶法制备ZnO薄膜及性质研究   总被引:4,自引:1,他引:4  
以二水醋酸锌为原料,使用溶胶凝胶法在(100)Si衬底上旋转涂敷得到ZnO薄膜.采用傅立叶变换红外光谱和X射线衍射(XRD)分析经N2、空气、O2不同气氛400℃退火ZnO薄膜的成分和结构差异.使用XRD、原子力显微镜和光致发光手段重点研究了N2气氛条件下,ZnO薄膜结构与发光特性随退火温度的变化规律,发现400℃下退火更适于干凝胶薄膜经历结构弛豫,生成具有(002)择优取向、性质优良的纳米晶ZnO薄膜.计算该样品的晶粒尺寸为41.6 nm,晶格常数a=0.325 3 nm,c=0.521 nm,其PL光谱出现495 nm附近强的绿光发射峰,可能源于ZnO纳米晶粒表面缺陷氧空位(Vo).随着退火温度升高,ZnO生成量减少、晶粒体表面积比(S/V)减小共同作用导致绿光峰强度变弱.  相似文献   

7.
合成了新显色剂4-(2-吡啶偶氮)-邻苯二酚(PAPC),并研究该试剂与Co(Ⅱ)、Co(Ⅲ)的显色反应。在pH=10.5缓冲溶液中,该试剂分别与Co(Ⅱ)、Co(Ⅲ)反应都能生成稳定的红色配合物,其最大吸收波长分别为518 nm和514 nm ,表观摩尔吸光系数分别为5.04×10  相似文献   

8.
以丙烯酸(AA)为小单体,异丁烯基聚氧乙烯醚(TPEG)为大单体,过硫酸铵为引发剂,在氮气气氛下发生水溶液低转化率自由基聚合,生成梳状共聚物AA-TPEG。单体的转化率用凝胶色谱(GPC)测定,采用前末端模型的共聚物组成方程的曲线交点法计算单体的竞聚率。结果表明,r1AA=1.54,r′1AA=1.06,r2TPEG=r′2TPEG=0,AA更易发生自聚。  相似文献   

9.
氮气保护下用亚碘酰苯氧化苯酚锰四苯基叶琳C_6H_5OMn(Ⅲ)TPP,合成了标题化合物0=Mn(Ⅳ)TPP.0=Mn(Ⅳ)TPP的可见吸收光谱在428nm和522nm分别有一强的Soret带吸收和弱的肩峰;红外光谱在1050cm~(-1)处有Mn=0的特征吸收.它能氧化苯乙烯、环乙烯和三苯基膀  相似文献   

10.
利用金属有机化合物气相沉积(MOCVD)技术生长了GaInP/(AlxGa1-x)InP多量子阱(MQW)结构材料,对其进行光荧光特性测量,观察到在波长λ=647 8nm和λ=861 6nm处分别存在一个强发光锋和一个弱发光峰.理论计算和实测结果基本一致.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

14.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

15.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

16.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

17.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

18.
For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the  相似文献   

19.
Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of  相似文献   

20.
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with  相似文献   

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