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1.
基于密度泛函理论B3LYP/6-311++G(d,p)方法,对(BCO)5与3d过渡金属离子Fe2+,Co2+,Ni2+形成的夹层配合物进行了稳定性与结构方面的计算研究.计算结果表明,与Cp-具有等瓣相似性的(BCO)5-可以形成类似于二茂化合物的夹层配合物.[(BCO)5]2M(M=Fe,co,Ni)的结合能小于相应Cp2M的结合能.对[(BCO)5]2Fe的电子结构进行了详细的分析,发现其前线轨道与Cp2Fe有着较大的不同.通过电子结构分析,很好地解释了为什么[(BCO)5]2Co的对称性是C2v,为什么[(BCO)5]2Ni是一个具有理想D5d对称性的三重态结构;三种标题化合物的结合能顺序为[(BCO)5]2Fe>[(BCO)5]2Co>[(BCO)5]2Ni.并给出了这一稳定性顺序的原因.  相似文献   

2.
采用机械合金化方法制备了Fe i Si,Fe Co Si三元系合金,利用X射线衍射仪研究了合金化过程中的相变行为.结果表明,Fe40Ni40Si20经36h球磨可形成αFe(bcc)和γFe(fcc)两相混合固溶体,继续球磨,过饱和α相逐渐分解并向γ相转化,72h后可得单相γFe过饱和固溶体.Fe40Co40Si20经36h可得αFe过饱和固溶体,继续球磨未发现新相生成.  相似文献   

3.
Because of the potential carcinogenic effects and difficult degradation of azo dyes, their degradation has been a longstanding problem. The degradation of azo dye Direct Blue 6(DB6) using ball-milled(BM) high-entropy alloy(HEA) powders was characterized in this work. Newly designed AlFeMnTiM(M = Cr, Co, Ni) HEAs synthesized by mechanical alloying(MA) showed excellent performance in the degradation of azo dye DB6. The degradation efficiency of AlFeMnTiCr is approximately 19 times greater than that of the widely used commercial Fe–Si–B amorphous alloy ribbons and more than 100 times greater than that of the widely used commercial zero-valent iron(ZVI) powders. The galvanic-cell effect and the unique crystal structure are responsible for the good degradation performance of the BM HEAs. This study indicates that BM HEAs are attractive, valuable, and promising environmental catalysts for wastewater contaminated by azo dyes.  相似文献   

4.
Because of the potential carcinogenic effects and difficult degradation of azo dyes, their degradation has been a longstanding problem. The degradation of azo dye Direct Blue 6(DB6) using ball-milled(BM) high-entropy alloy(HEA) powders was characterized in this work. Newly designed AlFeMnTiM(M = Cr, Co, Ni) HEAs synthesized by mechanical alloying(MA) showed excellent performance in the degradation of azo dye DB6. The degradation efficiency of AlFeMnTiCr is approximately 19 times greater than that of the widely used commercial Fe–Si–B amorphous alloy ribbons and more than 100 times greater than that of the widely used commercial zero-valent iron(ZVI) powders. The galvanic-cell effect and the unique crystal structure are responsible for the good degradation performance of the BM HEAs. This study indicates that BM HEAs are attractive, valuable, and promising environmental catalysts for wastewater contaminated by azo dyes.  相似文献   

5.
合成了[N-(2-脱氧-β-D-吡喃葡糖-2-水杨醛胺)]M(Ⅱ)单核金属配合物(M=Cu,Zn,Co,Ni),使用分光光度法研究了该单核的在CTAB胶束溶液中催化PNPP水解反应动力学,用单核配合物金属胶束的三元复合动力学模型对实验结果进行了讨论。实验结果表明:这类配合物在CTAB胶束溶液中形成金属胶束后,催化水解的能力明显增强,在中性或偏碱性环境中对PNPP的水解具有很好的催化活性,且金属配合物催化水解的速率常数其大小顺序为Zn(Ⅱ),Cu(Ⅱ),Co(Ⅱ),Ni(Ⅱ)。  相似文献   

6.
The effects of partial substitution of La by Ce and Ni by Al, Fe, or Co in LaNi_5-based alloys on hydrogen storage performance were systematically studied. All samples were prepared using vacuum arc melting in an argon atmosphere. The results showed that for LaNi_(5-x)M_x(M = Al, Fe, or Co) alloys, the lattice constants and unit cell volumes increased with an increasing amount of Al and Fe. On the other hand, these parameters decreased upon partial substitution of La by Ce. In addition, the lattice constant remained almost constant in the La_(0.6)Ce_(0.4)Ni_(5–x)Cox alloys regardless of the value of x(x = 0.3, 0.6, or 0.9), as Ce might enhance the homogeneity of the CaCu_5-type phase in Co-containing alloys. The hydrogen storage properties of the alloys were investigated using pressure, composition, and temperature isotherms. The experimental results showed that the plateau pressure decreased with an increasing content of Al, Fe, or Co, but it increased with Ce addition. Furthermore, the plateau pressures of all Co-containing alloys were almost identical upon substitution with Ce. Finally, the enthalpy(ΔH) and entropy(ΔS) values for all alloys were calculated using van't Hoff plots. The relationship between the lattice parameters and enthalpy changes for hydrogenation will be discussed.  相似文献   

7.
纳米金属酞菁MPc(M=Fe,Co,Ni,Cu和Zn)的合成与表征   总被引:1,自引:0,他引:1  
采用溶剂热方法以邻苯二甲腈为原料、乙二醇为溶剂在反应釜中合成了各种形貌的Fe,Co,Ni,Cu和Zn纳米金属酞菁化合物,并对它们进行了电子扫描电镜、XRD、红外光谱及紫外-可见光谱表征.结果表明,产品纯度高,产率大,形貌独特.  相似文献   

8.
本文通过对M、R(I,M)、G(I,M)的局部同调模的研究得到几个定理。  相似文献   

9.
本文用柠檬酸络合法制取了比表面为18.3~31.2m~2/g的LaMO_3(M-Cr,Mn,Fe,Co,Ni)系列化合物。X射线衍射(XRD)鉴定均为单一相钙钛矿型氧化物。LaCrO_3与LaFeO_3物属于正交晶型;LaMnO_3,LaCoO_3和LaNiO_3属三方晶型。在反应温度低于300℃时,一氧化碳氧化反应催化活性次序为:LaMnO_3>LaCoO_3>LaNiO_3>LaFeO_3>LaCrO_3,呈现出LaMO_3晶格氧化合能愈低,催化活性愈好的规律。  相似文献   

10.
柠檬酸络合法制备钙钛矿LaMO3(M=Co,Mn,Fe).对于己烷的完全氧化反应和甲烷完全氧化反应过程的活性进行测试,催化剂的催化活性顺序如下:LaCoO3〉LaMnO3〉LaFeO3,得出了相同的规律性:在氧化过程中,温度在250℃~300℃左右存在游离态的氧;温度高于300℃时,游离态的氧消失.  相似文献   

11.
基于Becker界面能模型,由合金相图和液态合金的过剩热力学数据,计算了M—Cu(M:Fe,Co)包晶合金亚稳液相分离时液相间的界面能。  相似文献   

12.
采用水热方法合成2种均苯三甲酸根配位聚合物{\[Cu2(Hbtc)2(H2O)6]·ppz·H2O}n(1)和{[Co2(btc)2(H2O)6]·(H2ppz)·(H2O)}n(2)(H3btc=均苯三甲酸,
ppz=哌嗪), 通过红外光谱(IR)、 紫外 可见\|近红外吸收光谱(UV-Vis-NIR)、 元素分析和X射线单晶衍射(XRD)对配位聚合物进行表征, 利用表面光电压光谱(SPS)考察配位聚合物的光伏性能, 并将SPS与UV Vis吸收光谱进行关联, 采用半导体能带理论与晶体场理论分析且指认各响应带. 结果表明: 配位聚合物1和2均属于三斜晶系, P-1空间群; 二者具有均苯三甲酸根桥连的1D链状结构, 不对称单元中均包含2个晶体学不等效的M(Ⅱ)离子(M1=Cu,M2=Co); 二者中心金属离子的配位构型不同, 相同有机分子的存在形式不同; 2种配位聚合物在紫外 可见光诱导下均产生光伏响应, 且配位聚合物中心离子的配位环境对光伏响应影响较大.  相似文献   

13.
(e,M)-内射模     
本文引入了(e,M)-内射模的概念.设M是任意一个固定的右R-模.称右R-模X是(e,M)-内射模,如果对任意的基本单同态f:K→M,从K到X的任意同态都能扩张到M.本文给出了(e,M)-内射模的一些性质和刻画.  相似文献   

14.
引进(M,H)临界矩阵的概念,研究由广义对称算子诱导的两非零广义对称张量相等的必要条件和VX∈Mn(C),多项式恒等dHM(AX)=dHM(XA)成立的充要条件,这里H是n次对称群Sn的子群,而dHM表示由群H的酉表示M诱导的矩阵函数.  相似文献   

15.
引入了(s,M)-投射模的概念.设M是任意一个固定的右R-模,称右R-模P是(s,M)-投射模,如果对任意的多余满同态g:M→N,从P到N的任意同态都能提升到M.给出了(s,M)-投射模的一些性质和刻画.  相似文献   

16.
作者合成和表征了双-{N-[2-脱氧-β-D-吡喃葡糖-2-(3-甲酰基水杨酸胺)]}M2(Ⅱ)配合物(M=Cu,Zn,Co);研究了该双核金属配合物在CTAB胶束溶液中催化PNPP水解反应动力学;用双核复合物金属胶束的三元复合动力学模型对实验结果进行了定理处理,结果表明:配合物在CTAB胶束溶液中形成金属胶束后,催化水解的能力明显增强,可使反应速率提高几百倍至二千多倍,金属配合物催化水解的速率常数大小顺序为Cu(Ⅱ),Zn(Ⅱ)和Co(Ⅱ)。  相似文献   

17.
以XPS表征了LaMO3(M=Fe,Co,Ni)晶体表面氧的性质,区分了XPS谱中二种O1s峰.由O吸峰的相对强度获得了LaMO3表面吸附O2性能的变化规律,并得到了O2吸附量(脉冲法)实验结果的映证.CO氧化反应活性测定发现:300℃下,LaMO3活性顺序为LaCoO3>LaNiO3>LaFeO3,与其O2吸附量大小顺序相一致.  相似文献   

18.
作为ojective模的推广,引入了A(X,M) ojective模的概念,并给出了A(X,M) ojective模的等价刻画.  相似文献   

19.
镍氢二次电池的电极材料包含大量镍、钴、稀土等有价金属元素,将其进行回收和资源化利用,对于降低电池生产成本、减少环境污染具有重要意义.使用NaBH4作为还原剂,在不同浓度的KOH溶液中处理废旧镍氢电池正极,实现钴的溶解,从而与氢氧化镍正极材料分离.结果表明,当KOH浓度为11.0mol/L时,所得氢氧化镍样品中钴的含量达到最低值1.84%(质量分数).此外,借助空气氧化和肼还原过程,可将溶解在碱液中的钴转化为可用于镍氢电池正极的Co(OH)_2导电添加剂.  相似文献   

20.
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