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1.
许正  刘军 《化学研究与应用》2002,14(2):157-159,140
本文在对O1(^1△g)最佳气相传输温度计算的分析基础上,从防止O1(^1△g)在经过渡段的淬来,气流温度对氧碘混合程度和对氧碘化学反应效率的影响三个方面进行了讨论,指出了获得最佳O1(^1△g)气相传输温度的途径。同时还讨论了实现激光器低温运行提高出光功率的可行性。  相似文献   

2.
聚1—甲基—2—吡咯烷酮修饰碘因子化学传感器的研究   总被引:2,自引:0,他引:2  
《分析测试学报》1997,16(4):69-71
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3.
The absolute O2 (1Δ)concentration measurement performed for a singlet oxygen generator(SOG)by using the infrared radiation-calorimetry method is reported with a detailed discussion of its principle and related technique. The influence of O2 (1Δ)gas temperature variation is considered and the corresponding correction has been made,which is neglected by the previous researchers and may cause a significant error in the case of measurement for the large O2 (1Δ)flowrate. Furthermore,an automatically balanced Wheatstone bridge circuit,which is necessary for O2 (1Δ)detection on the SOG of short operation period,is designed and tested by measuring the heat capacity of oxygen. The final error analyses give out a total relative error of ±16% for the O2 (1Δ)concentration,which mainly arises from the measurements of infrared radiation,pressure and temperature at the optical cell.  相似文献   

4.
王乃兴 《合成化学》2001,9(4):350-351
Fullerene[60]在光的作用下可以诱导产生单线态氧(^1O2),C60H36是一个富电子化合物,在室温下,单线态氧可以氧化C60H36,使透明的C60H36溶液(甲苯和已烷作溶剂)在短时间内变混浊,结果产生氧化产物C60H36-x(x=1-18)。  相似文献   

5.
采用质量损失法、碘量滴定法和正电子湮没寿命谱研究了 La_2NiO_(4+δ)透氧膜的非化学计量,并表征了该材料的氧渗透性能,探讨了 La_2NiO_(4+δ)的非化学计量缺陷与氧渗透性能之间的关系。研究结果表明, La_2NiO_(4+δ)的氧渗透通量随δ的增大而增大。  相似文献   

6.
用密度泛函理论(DFT)的B3-LYP方法和原子簇模型研究了碘和修饰银(110)表面对甲醇吸附的影响。结果表明,甲醇分子在干净的银表面吸附很弱甚至不吸附,但在氧或碘修饰过的银表面上,由于预吸附导致吸附能的增加而变得容易吸附。并进一步采用目前较新的映像电荷模型计算验证了在甲醇部分氧化制甲醛反应中氧或碘对银催化剂表面修饰的本质是电荷修饰这一推论,为实验中如何筛选修饰提供了良好的判据。  相似文献   

7.
以AlCl3 为络合物配体, 研究Sm2O3Eu2O3Gd2O3 的分离特性。结果表明, 其传输能力为:Sm ≈Gd> Eu, 氯化物主要在980 ~1100 K 沉积。不同温区的最大分离系数分别为: βEu/Sm;1200 K= 1-70 ,βEu/Gd;1300 K= 1-88 , βSm/Gd;1300 K = 1-24 , β′Sm/Eu;850 ~880 K= 2-76 , β′Gd/Eu;880~900 K = 2-83 , β′Gd/Sm;800 K=1-12 , 高于传统的湿法分离系数。  相似文献   

8.
A detailed theoretical study of the potential energy surface of poorly understood ion-molecule reaction of NH(2)(-) and O(2) (a(1)Δ(g)) is explored at the density functional theory B3LYP/6-311++G(d,p), ab initio of QCISD/6-311++G(d,p) and CCSD(T)/6-311++G(3df, 2pd) (single-point) theoretical levels for the first time. It is shown that there are six total possible products from P(1) to P(6) on the singlet potential energy surface. Among these, the charge-transfer product P(1) (NH(2) + O(2)(-)) is the most favorable product with predominant abundances, whereas P(4) (NO(-) + H(2)O) and P(2) (HNO + OH(-)) may be the second and third feasible products followed by the almost neglectable P(3) (NO(2)(-) + H(2)), while P(5) (c-NO(2)(-) + H(2)) and P(6) (ONO(-) + H(2)) will not be observed due to their either high barriers or being secondary products. The present theoretical study points out that besides P(1) (NH(2) + O(2)(-)) and P(2) (HNO + OH(-)), P(4) (NO(-) + H(2)O) should be also observed, which is different from the previous experiment study by Anthony Midey et al. in 2008. In addition, almost all of the reaction pathways to products are exothermic and the reaction rate should be very fast since the reaction barriers are very low except for P(5) (c-NO(2)(-) + H(2)) which is in agreement with the measured total reaction rate constant k = 9.0 × 10(-10) cm(3)s(-1) at 300 K in the experiment study. It is expected that the present theoretical study may be helpful for the understanding of the reaction mechanism related to NHX(-), NX(2)(-), PHX(-), and PX(2)(-) (X = H, F, and Cl).  相似文献   

9.
用密度泛函理论(DFT)的B3-LYP方法和原子簇模型研究了碘和修饰银(110)表面对甲醇吸附的影响。结果表明,甲醇分子在干净的银表面吸附很弱甚至不吸附,但在氧或碘修饰过的银表面上,由于预吸附导致吸附能的增加而变得容易吸附。并进一步采用目前较新的映像电荷模型计算验证了在甲醇部分氧化制甲醛反应中氧或碘对银催化剂表面修饰的本质是电荷修饰这一推论,为实验中如何筛选修饰提供了良好的判据。  相似文献   

10.
Laboratory measurements are reported of the rate coefficient for collisional removal of O(2)(X(3)Σ(g)(-), υ = 1) by O((3)P), and the rate coefficients for removal of O(2)(a(1)Δ(g), υ = 1) by O(2), CO(2), and O((3)P). A two-laser method is employed, in which the pulsed output of the first laser at 285 nm photolyzes ozone to produce oxygen atoms and O(2)(a(1)Δ(g), υ = 1), and the output of the second laser detects O(2)(a(1)Δ(g), υ = 1) via resonance-enhanced multiphoton ionization. The kinetics of O(2)(X(3)Σ(g)(-), υ = 1) + O((3)P) relaxation is inferred from the temporal evolution of O(2)(a(1)Δ(g), υ = 1), an approach enabled by the rapid collision-induced equilibration of the O(2)(X(3)Σ(g)(-), υ = 1) and O(2)(a(1)Δ(g), υ = 1) populations in the system. The measured O(2)(X(3)Σ(g)(-), υ = 1) + O((3)P) rate coefficient is (2.9 ± 0.6) × 10(-12) cm(3) s(-1) at 295 K and (3.4 ± 0.6) × 10(-12) cm(3) s(-1) at 240 K. These values are consistent with the previously reported result of (3.2 ± 1.0) × 10(-12) cm(3) s(-1), which was obtained at 315 K using a different experimental approach [K. S. Kalogerakis, R. A. Copeland, and T. G. Slanger, J. Chem. Phys. 123, 194303 (2005)]. For removal of O(2)(a(1)Δ(g), υ = 1) by O((3)P), the upper limits for the rate coefficient are 4 × 10(-13) cm(3) s(-1) at 295 K and 6 × 10(-13) cm(3) s(-1) at 240 K. The rate coefficient for removal of O(2)(a(1)Δ(g), υ = 1) by O(2) is (5.6 ± 0.6) × 10(-11) cm(3) s(-1) at 295 K and (5.9 ± 0.5) × 10(-11) cm(3) s(-1) at 240 K. The O(2)(a(1)Δ(g), υ = 1) + CO(2) rate coefficient is (1.5 ± 0.2) × 10(-14) cm(3) s(-1) at 295 K and (1.2 ± 0.1) × 10(-14) cm(3) s(-1) at 240 K. The implications of the measured rate coefficients for modeling of atmospheric emissions are discussed.  相似文献   

11.
The emission spectra of BiO has been first obtained by studying the reaction: Bi+O_2(~1△_g)in the atomic-beam apparatus. 22 new bands has been obtained from the emission spectra of BiO (A ~2Π_g) which are attributed to the collisional energy transfer process of BiO(X,v)+O_2(b ~1Σ_g~+). The O_2(b ~1Σ_g~+) is produced by the following process: O_2(~1△_g)+O_2(~1△_g)→O_2(b ~1Σ_g~+)+O_2(X ~3Σ_g~-).  相似文献   

12.
13.
研究了1-甲基-2-吡咯烷酮在玻碳(GC)电极表面聚合的条件,测试了I--聚1-甲基-2-吡咯烷酮化学传感器的电化学性能。所制电极检测I-响应线性范围24×10-4~01mol/L,检测下限为10×10-4mol/L,电极的重现性及稳定性都较好,重复测定7次相对标准偏差为071%,可连续使用25天。Cl-、Br-、NO-3、SO2-4等阴离子对测定干扰较小  相似文献   

14.
李其明  李芳 《化学研究》2010,21(4):72-75
建立了钙钛矿材料中金属离子的碘滴定分析方法,并通过该方法对BaCe0.1CoxFe0.9-xO3-δ和BaZr0.1CoxFe0.9-xO3-δ钙钛矿透氧膜材料中钴铁离子价态进行了测定.研究表明,随着钴含量的增加,钴铁离子的平均价态呈下降趋势,这意味着氧空位浓度也在随之增加.对比发现在相同掺杂比例时(x),BaCe0.1CoxFe0.9-xO3-δ体系中钴铁离子的平均价态要低于BaZr0.1CoxFe0.9-xO3-δ系列中钴铁离子的平均价态,因此BaCe0.1CoxFe0.9-xO3-δ系列比BaZr0.1CoxFe0.9-xO3-δ系列拥有更多氧空位数.  相似文献   

15.
采用较新的半经验分子轨道方法Austin Model 1(简称AM1方法), 辅以Berny梯度优化方法, 对单线态氧(~1O_2)与咪唑的1,2-环加成反应,进行了理论研究。计算获得实验尚未检测到的4,5-二氧环丁烷(4,5-dioxetane)的结构, 并在反应势能面上找到单重态双自由基中间体及通过该中间体的两步反应的过渡态。通过对过渡态的结构特征、虚振动方向以及对反应过程的电荷分布情况、轨道相互作用等的分析, 说明该反应是经由单重态双自由基中间体的分步反应。两步反应的活化势垒分别为39.2 kJ·mol~(-1)和150.5 kJ·mol~(-1)。  相似文献   

16.
用 XPS 法和碘量法分析了 YBCO 超导体及有关化合物。结果表明 YBCO 超导体碘量滴定反应中的“两电子氧化剂”不是 Cu~(3+)离子,而可能是O_2~(2-)(或 O~(1-))种类的氧离子。  相似文献   

17.
用266nm激光光解CHBr3产生CH自由基, 利用精密控温仪控制反应温度, 测定CH(A→X)荧光的时间分辨信号, 测量了290K至653K范围内CH(A)被乙醇、丙醇、丁醇猝灭的速率常数, 利用修正的碰撞配合物模型, 定性解释了在多极吸引势与活化势垒的双重影响下, 猝灭截面与温度间的关系。  相似文献   

18.
张智 《应用化学》1987,(4):84-85
本文系统地研究了SnO2系和γ-Fe2O3元件在变温过程中与H2O(g)、O2(g)和还原性气体相互作用的规律。结果表明:Al2O3、MgO、Pd、Pt和Sb2O3均对元件的体电阻均有调制作用。Al2O3是以微粒状存在于元件内,它为元件提供了活化中心,提高了元件的灵敏度。而γ-Fe2O3具有超微细结构。  相似文献   

19.
胶束增稳室温磷光法中化学除氧技术的研究   总被引:6,自引:2,他引:4  
魏雁声  张苏社 《分析化学》1990,18(3):228-232
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20.
调节硫酸氧钒与盐酸羟胺溶液至pH~4制得的题目晶体属空间群P2_1/n,晶胞参数a=8.201,b=8.597,c=9.947A,β=93.00°,Z=4.结构解出精修后R因子为0.069.结果表明,不对称单位中二个羟胺根以侧接态与VO~(3+)配位,另一羟胺取端接态以O占据V的第五赤道配位位置,配位水处于氧钒基强键反位,Cl~-则在配阳离子界外以平衡电荷,晶体对的化学式确证为[(VO~(3+))(NH_2O~_)_2(NH_3O)(H_2O)][Cl~-]  相似文献   

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