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1.
本文用分极化曲线法研究了Pt电极上HPO^2-4阳极氧化的P2O^4-8的动力学与机理,由分解得到的O2和P2O^4-8的极化曲线的Tafel斜率,低极化区两者均为2.303TR/βF;而高极化区两者分别为2.303RT/2βF和2.303RT/βF(其中β≈0.5)。两者的动力学方程分别为低极化区:i(O2)=k1(HOP^2-4)(OH^-)expβψF/RT,i(P2O^4-8)=k1(HP  相似文献   

2.
通过分光光度法测定Sr^2+与FeO^2-4(aq)的平衡浓度,计算出SrFeO4在298K时的K^ ○SP常数和热力学函数ΔH^○f,ΔG^○f,S^○分别为2.02×10^-10,-1067.78kJmol^-1,-936.48kJmol^-51,51.90Jmol^-1.K^-1用SrSO4作参比,对所用方法的可靠性作了验证。  相似文献   

3.
本文推导了3d^4/3d^6离子在D4h对称下^5D、^3L(L=P,D,F,G,H)和^1L(L=S,D,F,G,H)态的哈密顿矩阵元,其中包括晶场、自旋-轨道、自旋-自旋相互作用及Trees'修正。  相似文献   

4.
研究共轭梯度算法的整体收敛性,在放宽了的强Wolfe搜索(18)、(19)下证明了[1]中提出的修正HS共轭梯度算法的收敛性,在充分下降性条件下,βk=maxβHSk,0{}时也具有整体收敛性,同时,βk=max0,βPRk{}时,利用Armijo搜索和Goldstein搜索的共轭梯度法也具有整体收敛性.  相似文献   

5.
本研究首次观察到在水溶液中溶解有Cl^-,NO3^-,F^-,HCO3^-和SO4^-五种阴离子时,只有F^-在浓度高于4.0mg/L时会对声致发光产生影响,当在4.0mg/L ̄2.0mg/L范围内改变F^-的浓度,声致发光强度随F^-浓度的增加而下降,F^-的引入使得空化区域的低温等离子体的形成变为可以控制。  相似文献   

6.
该文是用非限制性Hartree-Fock自洽场分子轨道方法UHF-SCF-MO研究含硝基化合物热解机理的第1报,通过AM1计算求得了反应CH3NO2→CH3+·NO2的过渡态和活化能,给出了热解位能曲线。经零点能校正,计算得活化能为119.53kJ·mol^-1,而以前的限制性Hartree-Fock计算不可能求得该自由基反应的过渡态和活化能。  相似文献   

7.
借助紫外一可见分光光度计测定了Cd^2+(aq)与FeO^2-4(aq)的平衡浓度,计算出CdFeO4在298K时的K^osp常数和热力学函数△H^of,△G^of,S^0分别为9.16*10^-10,-596.81kJ.mol^-1,451.31kJ.mol^-1,15.62J.mol^-1.K^-1。  相似文献   

8.
用与Hennekemper不同的方法研究了(f^k+1)^(k)的值分布,将Hennekemper所得的基本不等式推广至小函数情形,得到了如下定理:设f为超越亚纯函数,F=(f^k+1)^(k),k∈N,ψ为非零的小函数,则T(x,f)≤(1+2k+1/4k^2+2k-1)N(r,1/f)+4k+2/4k^2+2k-1N↑-(r,1/F-ψ)+S(r,f)。  相似文献   

9.
硅基取代环戊二烯基二羰基铁负离子[η^5-RC5H4Fe(CO)2]^-(R=SiMe3,I;Si2Me5,Ⅱ)与铁碘化合物(η^5-C5H5)Fe(CO)2I反应,除得到新的Fe-Fe化合物外,还分离到另两种母体Fe-Fe化合物;桥连化合物(η^5,η^5-C5H4SiM32OSiMe2C5H4)[Fe(CO)2I]2(6)与铁负离子[η^5-C5H5Fe(CO)2]^-(Ⅲ)的反应,仅分离到各  相似文献   

10.
为了探讨无血清培养细胞HICSF的自分泌调控机制,采用RT-PCR技术检测生长因子bFGF,TGFβ1和细胞因子IL-6,IL-8,G-CSF以及细胞因子受体IL-6R和IL-8R在HICSF细胞及其同基因来源的血清培养细胞HIC中的表达状况,同时用^3H-TdR掺入法观察重组IL-6和TGFβ1对这2种细胞生长的影响,以观察癌细胞在有血清和无血清培养条件下部分生长因子和细胞因子的表达及反应性差异  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.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

15.
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   

16.
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   

17.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

18.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

19.
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   

20.
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   

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