The CeTi 2O 6, which is formed above 1300 ℃ by ceramic method, was obtained at 700 ℃ using sol gel synthesis method. XRD analysis shows that there is 8% deficient of Ce in the structure. The chemical formula is C...The CeTi 2O 6, which is formed above 1300 ℃ by ceramic method, was obtained at 700 ℃ using sol gel synthesis method. XRD analysis shows that there is 8% deficient of Ce in the structure. The chemical formula is Ce 0.92 Ti 2O 5.84 , which has a monoclinic structure with space group of C 2/ m . Its cell parameters are a =0.9811(8) nm, b =0.3726(3) nm, c =0.6831(6) nm, and β =118.84°. After being treated at 1300 ℃ for 3 h, the system keeps stable but the deficient disappears, while the chemical formula change to the normal CeTi 2O 6, and the cell parameters are a =0.9813(3) nm, b =0.3752(4) nm, c =0.6883(5) nm, β =119.05°. The key to synthesis the precursors of CeTi 2O 6 is that Ti 4+ and Ce 3+ ions must reach the atomistic distributing state and prevent the oxidation of Ce 3+ during sol gel process.展开更多
The catalytic epoxidation of olefin was investigated on two copper complex-modified molybdenum oxides with a 3D supramolecular structure, [Cu(bipy)]4[Mo15O47].2H2O (1) and [Cu1(bix)][(Cu1bix) (δ-MoVl8O26)0....The catalytic epoxidation of olefin was investigated on two copper complex-modified molybdenum oxides with a 3D supramolecular structure, [Cu(bipy)]4[Mo15O47].2H2O (1) and [Cu1(bix)][(Cu1bix) (δ-MoVl8O26)0.5] (2) (bipy = 4,4'-bipyridine, bix = 1,4-bis(imidazole-1-ylmethyl)benzene). Both compounds were catalytically active and stable for the epoxidation of cyclooctene, 1-octene, and styrene with tert-butyl hydroperoxide (t-BuOOH) as oxidant. The excellent catalytic performance was attributed to the presence of stable coordination bonds between the molybdenum oxide and copper complex, which resulted in the formation of easily accessible Mo species with high electropositivity. In addition, the copper complex also acted as an active site for the activation of t-BuOOH, thus im- proving these copper complex-modified polyoxometalates.展开更多
The kinetics of ternary complex formation involving Cu(5-X-1, 10-phen) and threonine (CuAL, A=5-X-1, 10-phen; L=threonine or represented by O-N; X=NO_2, Cl, H, CH_3) has been studied by temperature-jump and stopped-fl...The kinetics of ternary complex formation involving Cu(5-X-1, 10-phen) and threonine (CuAL, A=5-X-1, 10-phen; L=threonine or represented by O-N; X=NO_2, Cl, H, CH_3) has been studied by temperature-jump and stopped-flow methods. The formation rate constants, k_f(M^(-1).s^(-1)), for the complexation reaction, CuA + LCuAL, are as follows; X=NO_2, 8.68×10~8; X=Cl, 7.13×10~8; X=H, 6.12×10~8; X=CH_3, 5.42×10~8. The rate constants for zwitterion attack are nil within experimental error. It has been found that a linear free energy relationship exists between the stability(logK_(CuAL)^(CuA) of the complexes CuAL and log kf as follows: IogK_(CuAL)^(CuA)=0.13 + 0.83 logk_f, r=0.99. It suggested that the formation rate governed the stability of the ternary complexes. The rates of formation of the ternary complexes increased with decreasing electron-donating property of the substituents. A linear relationship was found to exist as expressed by the following equation: log(k_f^R/k_F^O) = 0.097σ, r=0.96. A mechanism involves a rapid equilibrium between CuA and L followed by a slow ring closure of L.展开更多
In order to improve the quality of sinter produced by Baiyunebo iron ore concentrate,the effects of compound silicate gangue containing kalium and natrium on formation of complex calcium ferrite were studied using min...In order to improve the quality of sinter produced by Baiyunebo iron ore concentrate,the effects of compound silicate gangue containing kalium and natrium on formation of complex calcium ferrite were studied using mini-sintering test device,optical microscope(OM) analysis and scanning electron microscope(SEM)/energy dispersive X-ray spectroscopy(EDX) analysis.The results show that with the increasing of K2O and Na2O content in sintering samples,K2O and Na2O highly enriched in the glassy phases,the contents of complex calcium ferrite and hematite in sinter decreased and the porosity increased;the mineral microstructure exhibited large cavities and thin framework and became inhomogeneous.The compound silicate gangue containing kalium and natrium significantly inhibited the generation of complex calcium ferrite(SFCA).When the content of K2O and Na2O was higher in samples,a part of K2O and Na2O entered into complex calcium ferrite,which caused the fine grains of SFCA with acicular and columnar to agglomerate into coarse grains,and its bonding effect to iron oxides reduced.The content of K2O and Na2O in sinter had effects on quantity,composition and morphology of complex calcium ferrite.展开更多
The formability of complex flourides has been studied by chemical bond parameter-pattern recognition method. In a multi-dimensional space spanned by ionic radius, ionic polarizability, electronegativity and ionic char...The formability of complex flourides has been studied by chemical bond parameter-pattern recognition method. In a multi-dimensional space spanned by ionic radius, ionic polarizability, electronegativity and ionic charge of the metal elements, the binary complex flouride-forming systems and binary flouride systems without complex flouride formation distribute in different regions with a clear-cut boundary. The mathematical models obtained are useful for new complex flouride predicton.展开更多
The structure of addition compound Cu(phen)3(PMoxdH)(CO4)2 was establish ed by means of X-ray crystallography,where PMoxdH is N,N-Bi(2-pyridyl-methyl)-oxamide,in which six nitrogen atoms of the three 1,10,-phen-anthro...The structure of addition compound Cu(phen)3(PMoxdH)(CO4)2 was establish ed by means of X-ray crystallography,where PMoxdH is N,N-Bi(2-pyridyl-methyl)-oxamide,in which six nitrogen atoms of the three 1,10,-phen-anthroline bind to the copper ion and the oxygen atom of PMoxdH is uncoordinated.展开更多
In this study,the electronic transition properties and structural analysis of the metal complexes(Ni(Ⅱ),Co(Ⅱ),Cu(Ⅱ)and Mn(Ⅱ))of three different polymer ligands were performed by using XRF and X-ray diffraction(XRD...In this study,the electronic transition properties and structural analysis of the metal complexes(Ni(Ⅱ),Co(Ⅱ),Cu(Ⅱ)and Mn(Ⅱ))of three different polymer ligands were performed by using XRF and X-ray diffraction(XRD)techniques,respectively.The structural analysis of the polymers and their complexes were performed by XRD technique and some of the polymers were found to be in the face-centred cubic(fcc)structure.In addition,the values of the present K X-ray intensity ratios are significantly greater than the values reported in literature.展开更多
In this study, the amounts of odorous carbonyl compounds (OCCs) including acetaldehyde (Acet-A), propionaldehyde (Pron-A), butylaldehyde (Buty-A), iso-valeric aldehyde (Iso-Vale-A) and n-valeric aldehyde (N...In this study, the amounts of odorous carbonyl compounds (OCCs) including acetaldehyde (Acet-A), propionaldehyde (Pron-A), butylaldehyde (Buty-A), iso-valeric aldehyde (Iso-Vale-A) and n-valeric aldehyde (N-Vale-A) emitted from a fishery industrial complex near the exhibition facilities of "Expo 2012 Yeosu Korea" were measured. Acet-A was found to be the most abundant OCC, and the total concentrations of the OCCs were the highest in the summer. However, due to vehicular exhaust and photochemical reactions, the concentrations of some of the OCCs presented their highest levels in the fall. A significant correlation between Acet-A and Buty-A was found at the major fishery facilities (r = 0.816, p = 1.87E-15, n = 60) and at the border areas (r = 0.809, p = 3.40E-12, n = 48) of this fishery industrial complex. The concentrations of OCCs at the border areas were not worse than those at the urban areas in other places, indicating that the concentrations of ambient OCCs at the border areas were not greatly influenced by manmade activities.展开更多
Crystal structure of nickel(II) complex with a new 14 membered tetraazamacrocyclic ligand 5,12-diphenyl-7,14-dimethyl-1,4,8,11-tetraazacyclotetradecane-N’,N-diacetic acid,Ni[N<sub>4</sub>C<sub>10&...Crystal structure of nickel(II) complex with a new 14 membered tetraazamacrocyclic ligand 5,12-diphenyl-7,14-dimethyl-1,4,8,11-tetraazacyclotetradecane-N’,N-diacetic acid,Ni[N<sub>4</sub>C<sub>10</sub>(CH<sub>2</sub>COO)<sub>2</sub>(C<sub>6</sub>H<sub>5</sub>)<sub>2</sub>]·2H<sub>2</sub>O, M<sub>r</sub>= 589. 38 is reported.It crystallizes in monoclinic P2<sub>1</sub>/c space group with a=12.949(6),b=16.373(3),c=14.232(16),β=98.68(6)°,V=2982.9(7),Z=4,D<sub>c</sub>=1.312 gcm-3,μ=6.953 cm-1,F(000)=1256.0.Finally,the structure was refined to R=0.080,R<sub>w</sub>=0.065 for 2952 reflections.The central nickel ion of the complex forms an octahedron with four nitrogen atoms of the macrocycle and two oxygen atoms of the appended carboxylate groups.Two phenyl planes of the ligand are almost parallel to each other.展开更多
Interaction between chiral diols BDPDD, DMBDPD and BINOL with prochiral compounds was examined and some new supramolecular complexes were prepared. It was found that these chiral hosts could include prochiral vips,...Interaction between chiral diols BDPDD, DMBDPD and BINOL with prochiral compounds was examined and some new supramolecular complexes were prepared. It was found that these chiral hosts could include prochiral vips, a, b-unsaturated compounds or piper- azinedione derivatives to give inclusion crystals in different molar ratio. Formations of these supramolecular complexes were characterized by the data of IR and 1H NMR spectra.展开更多
Layered compound zirconium bis(monohydrogenphosphate)(alpha-ZrP) intercalated with rare earth complex Eu(DBM)(3)phen was prepared. The pre-intercalation of p-methoxyaniline into alpha-ZrP makes the interlayer separati...Layered compound zirconium bis(monohydrogenphosphate)(alpha-ZrP) intercalated with rare earth complex Eu(DBM)(3)phen was prepared. The pre-intercalation of p-methoxyaniline into alpha-ZrP makes the interlayer separation large enough to exchange PMA with europium complex, thus, the luminescent assembly was prepared. This was confirmed by X-ray diffraction, UV-visible spectra and elemental analysis. The fluorescence spectra and lifetime of the assembly were also presented.展开更多
Some new Schiff bases were synthesized by the condensation of equimolar quantities of salicylaldehyde and 2-amino-5-phenylazo-pyridine or its derivatives in dry benzene(1):Metal complexes of the type ML_2and M'L_3...Some new Schiff bases were synthesized by the condensation of equimolar quantities of salicylaldehyde and 2-amino-5-phenylazo-pyridine or its derivatives in dry benzene(1):Metal complexes of the type ML_2and M'L_3 where M=Cu^(2+),Co^(2+),Ni^(2+),Mn^(2+)Pd^(2+),M'=Fe^(3+)and L=different newly synthesized monobasic Schiff bases were prepared in absolute ethanolic medium(2)and characterized by elementary analysis,conductance measurements,infrared spectra,electronic spectra,magnetic moments studies.展开更多
【目的】解决现有地形复杂度误差评价方法主观性强、缺少误差解析式的问题。【方法】利用误差传播定律推导了局部高差、局部标准差、局部褶皱度和局部全曲率的中误差表达式,依据复合地形因子误差传递规律构建了复合地形复杂度指标(compo...【目的】解决现有地形复杂度误差评价方法主观性强、缺少误差解析式的问题。【方法】利用误差传播定律推导了局部高差、局部标准差、局部褶皱度和局部全曲率的中误差表达式,依据复合地形因子误差传递规律构建了复合地形复杂度指标(compound terrain complexity index,CTCI)提取的误差估计模型(error estimation model for CTCI,CEEM)。通过模拟数字高程模型(digital elevation model,DEM)试验验证了该模型的有效性,并采用三个不同地貌区域的实体DEM进行CEEM泛化试验。【结果】在不同噪声影响下,CEEM平均误差、均方差、残差和平均绝对百分比误差最大值分别为-2.1×10^(-3)、7.99×10^(-6)、8.4×10^(-3)和22.8%,决定系数均在0.961以上,CEEM整体误差微小;不同地貌类型的地形复杂度提取误差存在差异,试验统计结果表明误差由大到小依次为高山、中山、丘陵。【结论】CEEM能定量化描述地形复杂度的提取误差,可为不同复杂地形地貌区域提取复合地形复杂度指标提供参考。展开更多
<span style="font-family:Verdana;">Coordination compounds of 3-hydroxy-2-methyl-4</span><i><span style="font-family:Verdana;">H</span></i><span style="fo...<span style="font-family:Verdana;">Coordination compounds of 3-hydroxy-2-methyl-4</span><i><span style="font-family:Verdana;">H</span></i><span style="font-family:Verdana;">-pyran-4-one with </span><span style="font-family:Verdana;">iron(III), cobat(III) and chromium(III) were synthesized with M:L (1:2)</span><span style="font-family:Verdana;">. Mixed ligand coordination compounds of 3-hydroxy-2-methyl-4</span><i><span style="font-family:Verdana;">H</span></i><span style="font-family:Verdana;">-pyran-4-one and 1,2-diaminocyclohexane using the same metal ions were also synthesized </span><b><span style="font-family:Verdana;">M:L1</span></b><span style="font-family:Verdana;">:</span><b><span style="font-family:Verdana;">L2</span></b><span style="font-family:Verdana;"> (1:1:1) where </span><b><span style="font-family:Verdana;">L1</span></b><span style="font-family:Verdana;"> is 3-hydroxy-2-methyl-4</span><i><span style="font-family:Verdana;">H</span></i><span style="font-family:Verdana;">-pyran-4-one and </span><b><span style="font-family:Verdana;">L2</span></b><span style="font-family:Verdana;"> is 1,2-diaminocyclohexane. The coordination compounds obtained were characterized using electronic and infrared spectral analyses, magnetic susceptibility and percentage metal analysis. They were also evaluated for their cytotoxic and antioxidant activities. The result obtained suggested that octahedral geometry was obtained for all the compounds, as a result of additional two molecules of the solvent coordinated to the metal ions. Both the primary and secondary ligands coordinated in a bidentate fashion. The synthesized compounds exhibited moderate cytotoxicity, although none was as active as the standard. The cobalt(III) mixed ligand complex elicited the highest activity. The synthesized compounds all exhibited good to moderate antioxidant activity.</span>展开更多
针对复杂电磁环境下雷达复合干扰识别困难和网络模型复杂度高的问题,将多标签分类与改进的ShuffleNet V2相结合,提出一种轻量化的多标签ShuffleNet(multi-labeling ShuffleNet, ML-SNet)雷达复合干扰识别算法。首先,使用轻量化的Shuffle...针对复杂电磁环境下雷达复合干扰识别困难和网络模型复杂度高的问题,将多标签分类与改进的ShuffleNet V2相结合,提出一种轻量化的多标签ShuffleNet(multi-labeling ShuffleNet, ML-SNet)雷达复合干扰识别算法。首先,使用轻量化的ShuffleNet V2作为主干网络,引入SimAM(similarity-based attention module)注意力机制,提高网络特征提取能力。其次,使用漏斗激活线性整流函数(funnel activation rectified linear unit, FReLU)代替线性整流单元(rectified linear unit, ReLU)激活函数,减少特征图的信息损失。最后,使用多标签分类算法对网络输出进行分类,得到识别结果。实验结果表明,在干噪比范围为-10~10 dB的情况下,所提算法对15类雷达复合干扰的平均识别率为97.9%。与其他网络相比,所提算法具有较低的计算复杂度,而且识别性能表现最佳。展开更多
<span style="font-family:Verdana;">Coordination compounds of 2-amino-3-methylbutanoic acid were synthesized with chromium(III) and oxovanadium(IV) ions. M:L;1:2. Adducts of these complexes using 1,10-p...<span style="font-family:Verdana;">Coordination compounds of 2-amino-3-methylbutanoic acid were synthesized with chromium(III) and oxovanadium(IV) ions. M:L;1:2. Adducts of these complexes using 1,10-phenantroline and ethylenediamine were further synthesized, M:L, (1:2). These compounds were characterized using electronic, infra-red spectrophotometry, magnetic susceptibility measurement and percentage metal analyses. The zones of inhibition and minimum inhibitory concentrations of the compounds against eight microbes were studied. The results obtained indicated an octahedral geometry for the Cr(III) complexes, indicative of additional coordination of two water molecules. On the other hand a square pyramid geometry was obtained for the binary oxovanadium complex and its 1,10-phenantroline adduct. However</span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">,</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> for the oxovanadium ethylenediamine adduct a distorted octahedral geometry was proposed. The result for the antibacterial studies indicated that both mixed ligand complexes of 1,10-phenantroline exhibited good antibacterial activity, and in some cases better activity than the standard, streptomycin.</span></span></span>展开更多
The morphology of ZA-27 alloy reinforced by RE compounds and its wear-resistance were studied. It is found that some nodular second phases appear due to the addition of Si and RE, which can disperse in grain boundari...The morphology of ZA-27 alloy reinforced by RE compounds and its wear-resistance were studied. It is found that some nodular second phases appear due to the addition of Si and RE, which can disperse in grain boundaries or between dendrite crystals so that the alloy has been refined. Energy spectrum analysis of scanning electron microscope shows that the second phases are complex compounds containing RE, Al, Zn and Si. The micro- hardness test indicates that micro-hardness values of the compounds are higher than those of the matrix. The wear-resis tance of ZA-27 alloy reinforced by RE compounds is 4 times as high as that of ZA-27 alloy and also higher than that of ZA-27 alloy containing Si phase. The impact toughness of the alloy containing RE and Si is higher than that of the alloy containing Si.展开更多
文摘The CeTi 2O 6, which is formed above 1300 ℃ by ceramic method, was obtained at 700 ℃ using sol gel synthesis method. XRD analysis shows that there is 8% deficient of Ce in the structure. The chemical formula is Ce 0.92 Ti 2O 5.84 , which has a monoclinic structure with space group of C 2/ m . Its cell parameters are a =0.9811(8) nm, b =0.3726(3) nm, c =0.6831(6) nm, and β =118.84°. After being treated at 1300 ℃ for 3 h, the system keeps stable but the deficient disappears, while the chemical formula change to the normal CeTi 2O 6, and the cell parameters are a =0.9813(3) nm, b =0.3752(4) nm, c =0.6883(5) nm, β =119.05°. The key to synthesis the precursors of CeTi 2O 6 is that Ti 4+ and Ce 3+ ions must reach the atomistic distributing state and prevent the oxidation of Ce 3+ during sol gel process.
基金supported by the National Natural Science Foundation of China(21173100 and 21320102001)~~
文摘The catalytic epoxidation of olefin was investigated on two copper complex-modified molybdenum oxides with a 3D supramolecular structure, [Cu(bipy)]4[Mo15O47].2H2O (1) and [Cu1(bix)][(Cu1bix) (δ-MoVl8O26)0.5] (2) (bipy = 4,4'-bipyridine, bix = 1,4-bis(imidazole-1-ylmethyl)benzene). Both compounds were catalytically active and stable for the epoxidation of cyclooctene, 1-octene, and styrene with tert-butyl hydroperoxide (t-BuOOH) as oxidant. The excellent catalytic performance was attributed to the presence of stable coordination bonds between the molybdenum oxide and copper complex, which resulted in the formation of easily accessible Mo species with high electropositivity. In addition, the copper complex also acted as an active site for the activation of t-BuOOH, thus im- proving these copper complex-modified polyoxometalates.
文摘The kinetics of ternary complex formation involving Cu(5-X-1, 10-phen) and threonine (CuAL, A=5-X-1, 10-phen; L=threonine or represented by O-N; X=NO_2, Cl, H, CH_3) has been studied by temperature-jump and stopped-flow methods. The formation rate constants, k_f(M^(-1).s^(-1)), for the complexation reaction, CuA + LCuAL, are as follows; X=NO_2, 8.68×10~8; X=Cl, 7.13×10~8; X=H, 6.12×10~8; X=CH_3, 5.42×10~8. The rate constants for zwitterion attack are nil within experimental error. It has been found that a linear free energy relationship exists between the stability(logK_(CuAL)^(CuA) of the complexes CuAL and log kf as follows: IogK_(CuAL)^(CuA)=0.13 + 0.83 logk_f, r=0.99. It suggested that the formation rate governed the stability of the ternary complexes. The rates of formation of the ternary complexes increased with decreasing electron-donating property of the substituents. A linear relationship was found to exist as expressed by the following equation: log(k_f^R/k_F^O) = 0.097σ, r=0.96. A mechanism involves a rapid equilibrium between CuA and L followed by a slow ring closure of L.
基金Item Sponsored by National Natural Science Foundation of China(50944049)
文摘In order to improve the quality of sinter produced by Baiyunebo iron ore concentrate,the effects of compound silicate gangue containing kalium and natrium on formation of complex calcium ferrite were studied using mini-sintering test device,optical microscope(OM) analysis and scanning electron microscope(SEM)/energy dispersive X-ray spectroscopy(EDX) analysis.The results show that with the increasing of K2O and Na2O content in sintering samples,K2O and Na2O highly enriched in the glassy phases,the contents of complex calcium ferrite and hematite in sinter decreased and the porosity increased;the mineral microstructure exhibited large cavities and thin framework and became inhomogeneous.The compound silicate gangue containing kalium and natrium significantly inhibited the generation of complex calcium ferrite(SFCA).When the content of K2O and Na2O was higher in samples,a part of K2O and Na2O entered into complex calcium ferrite,which caused the fine grains of SFCA with acicular and columnar to agglomerate into coarse grains,and its bonding effect to iron oxides reduced.The content of K2O and Na2O in sinter had effects on quantity,composition and morphology of complex calcium ferrite.
文摘The formability of complex flourides has been studied by chemical bond parameter-pattern recognition method. In a multi-dimensional space spanned by ionic radius, ionic polarizability, electronegativity and ionic charge of the metal elements, the binary complex flouride-forming systems and binary flouride systems without complex flouride formation distribute in different regions with a clear-cut boundary. The mathematical models obtained are useful for new complex flouride predicton.
文摘The structure of addition compound Cu(phen)3(PMoxdH)(CO4)2 was establish ed by means of X-ray crystallography,where PMoxdH is N,N-Bi(2-pyridyl-methyl)-oxamide,in which six nitrogen atoms of the three 1,10,-phen-anthroline bind to the copper ion and the oxygen atom of PMoxdH is uncoordinated.
基金Scientific Research Fund of Kahramanmaras Sutcu Imam University,Turkey(2012/3-7YLS)
文摘In this study,the electronic transition properties and structural analysis of the metal complexes(Ni(Ⅱ),Co(Ⅱ),Cu(Ⅱ)and Mn(Ⅱ))of three different polymer ligands were performed by using XRF and X-ray diffraction(XRD)techniques,respectively.The structural analysis of the polymers and their complexes were performed by XRD technique and some of the polymers were found to be in the face-centred cubic(fcc)structure.In addition,the values of the present K X-ray intensity ratios are significantly greater than the values reported in literature.
基金support of this research program from the Jeonnam Green Environment Center (JNGEC),Korea
文摘In this study, the amounts of odorous carbonyl compounds (OCCs) including acetaldehyde (Acet-A), propionaldehyde (Pron-A), butylaldehyde (Buty-A), iso-valeric aldehyde (Iso-Vale-A) and n-valeric aldehyde (N-Vale-A) emitted from a fishery industrial complex near the exhibition facilities of "Expo 2012 Yeosu Korea" were measured. Acet-A was found to be the most abundant OCC, and the total concentrations of the OCCs were the highest in the summer. However, due to vehicular exhaust and photochemical reactions, the concentrations of some of the OCCs presented their highest levels in the fall. A significant correlation between Acet-A and Buty-A was found at the major fishery facilities (r = 0.816, p = 1.87E-15, n = 60) and at the border areas (r = 0.809, p = 3.40E-12, n = 48) of this fishery industrial complex. The concentrations of OCCs at the border areas were not worse than those at the urban areas in other places, indicating that the concentrations of ambient OCCs at the border areas were not greatly influenced by manmade activities.
文摘Crystal structure of nickel(II) complex with a new 14 membered tetraazamacrocyclic ligand 5,12-diphenyl-7,14-dimethyl-1,4,8,11-tetraazacyclotetradecane-N’,N-diacetic acid,Ni[N<sub>4</sub>C<sub>10</sub>(CH<sub>2</sub>COO)<sub>2</sub>(C<sub>6</sub>H<sub>5</sub>)<sub>2</sub>]·2H<sub>2</sub>O, M<sub>r</sub>= 589. 38 is reported.It crystallizes in monoclinic P2<sub>1</sub>/c space group with a=12.949(6),b=16.373(3),c=14.232(16),β=98.68(6)°,V=2982.9(7),Z=4,D<sub>c</sub>=1.312 gcm-3,μ=6.953 cm-1,F(000)=1256.0.Finally,the structure was refined to R=0.080,R<sub>w</sub>=0.065 for 2952 reflections.The central nickel ion of the complex forms an octahedron with four nitrogen atoms of the macrocycle and two oxygen atoms of the appended carboxylate groups.Two phenyl planes of the ligand are almost parallel to each other.
基金This work was supported by the National Natural Science Foundation of China (Project 29972033) and the Key Science Research Foundation of Hubei Province of China (Project 98IP1305).
文摘Interaction between chiral diols BDPDD, DMBDPD and BINOL with prochiral compounds was examined and some new supramolecular complexes were prepared. It was found that these chiral hosts could include prochiral vips, a, b-unsaturated compounds or piper- azinedione derivatives to give inclusion crystals in different molar ratio. Formations of these supramolecular complexes were characterized by the data of IR and 1H NMR spectra.
文摘Layered compound zirconium bis(monohydrogenphosphate)(alpha-ZrP) intercalated with rare earth complex Eu(DBM)(3)phen was prepared. The pre-intercalation of p-methoxyaniline into alpha-ZrP makes the interlayer separation large enough to exchange PMA with europium complex, thus, the luminescent assembly was prepared. This was confirmed by X-ray diffraction, UV-visible spectra and elemental analysis. The fluorescence spectra and lifetime of the assembly were also presented.
文摘Some new Schiff bases were synthesized by the condensation of equimolar quantities of salicylaldehyde and 2-amino-5-phenylazo-pyridine or its derivatives in dry benzene(1):Metal complexes of the type ML_2and M'L_3 where M=Cu^(2+),Co^(2+),Ni^(2+),Mn^(2+)Pd^(2+),M'=Fe^(3+)and L=different newly synthesized monobasic Schiff bases were prepared in absolute ethanolic medium(2)and characterized by elementary analysis,conductance measurements,infrared spectra,electronic spectra,magnetic moments studies.
文摘【目的】解决现有地形复杂度误差评价方法主观性强、缺少误差解析式的问题。【方法】利用误差传播定律推导了局部高差、局部标准差、局部褶皱度和局部全曲率的中误差表达式,依据复合地形因子误差传递规律构建了复合地形复杂度指标(compound terrain complexity index,CTCI)提取的误差估计模型(error estimation model for CTCI,CEEM)。通过模拟数字高程模型(digital elevation model,DEM)试验验证了该模型的有效性,并采用三个不同地貌区域的实体DEM进行CEEM泛化试验。【结果】在不同噪声影响下,CEEM平均误差、均方差、残差和平均绝对百分比误差最大值分别为-2.1×10^(-3)、7.99×10^(-6)、8.4×10^(-3)和22.8%,决定系数均在0.961以上,CEEM整体误差微小;不同地貌类型的地形复杂度提取误差存在差异,试验统计结果表明误差由大到小依次为高山、中山、丘陵。【结论】CEEM能定量化描述地形复杂度的提取误差,可为不同复杂地形地貌区域提取复合地形复杂度指标提供参考。
文摘<span style="font-family:Verdana;">Coordination compounds of 3-hydroxy-2-methyl-4</span><i><span style="font-family:Verdana;">H</span></i><span style="font-family:Verdana;">-pyran-4-one with </span><span style="font-family:Verdana;">iron(III), cobat(III) and chromium(III) were synthesized with M:L (1:2)</span><span style="font-family:Verdana;">. Mixed ligand coordination compounds of 3-hydroxy-2-methyl-4</span><i><span style="font-family:Verdana;">H</span></i><span style="font-family:Verdana;">-pyran-4-one and 1,2-diaminocyclohexane using the same metal ions were also synthesized </span><b><span style="font-family:Verdana;">M:L1</span></b><span style="font-family:Verdana;">:</span><b><span style="font-family:Verdana;">L2</span></b><span style="font-family:Verdana;"> (1:1:1) where </span><b><span style="font-family:Verdana;">L1</span></b><span style="font-family:Verdana;"> is 3-hydroxy-2-methyl-4</span><i><span style="font-family:Verdana;">H</span></i><span style="font-family:Verdana;">-pyran-4-one and </span><b><span style="font-family:Verdana;">L2</span></b><span style="font-family:Verdana;"> is 1,2-diaminocyclohexane. The coordination compounds obtained were characterized using electronic and infrared spectral analyses, magnetic susceptibility and percentage metal analysis. They were also evaluated for their cytotoxic and antioxidant activities. The result obtained suggested that octahedral geometry was obtained for all the compounds, as a result of additional two molecules of the solvent coordinated to the metal ions. Both the primary and secondary ligands coordinated in a bidentate fashion. The synthesized compounds exhibited moderate cytotoxicity, although none was as active as the standard. The cobalt(III) mixed ligand complex elicited the highest activity. The synthesized compounds all exhibited good to moderate antioxidant activity.</span>
文摘针对复杂电磁环境下雷达复合干扰识别困难和网络模型复杂度高的问题,将多标签分类与改进的ShuffleNet V2相结合,提出一种轻量化的多标签ShuffleNet(multi-labeling ShuffleNet, ML-SNet)雷达复合干扰识别算法。首先,使用轻量化的ShuffleNet V2作为主干网络,引入SimAM(similarity-based attention module)注意力机制,提高网络特征提取能力。其次,使用漏斗激活线性整流函数(funnel activation rectified linear unit, FReLU)代替线性整流单元(rectified linear unit, ReLU)激活函数,减少特征图的信息损失。最后,使用多标签分类算法对网络输出进行分类,得到识别结果。实验结果表明,在干噪比范围为-10~10 dB的情况下,所提算法对15类雷达复合干扰的平均识别率为97.9%。与其他网络相比,所提算法具有较低的计算复杂度,而且识别性能表现最佳。
文摘<span style="font-family:Verdana;">Coordination compounds of 2-amino-3-methylbutanoic acid were synthesized with chromium(III) and oxovanadium(IV) ions. M:L;1:2. Adducts of these complexes using 1,10-phenantroline and ethylenediamine were further synthesized, M:L, (1:2). These compounds were characterized using electronic, infra-red spectrophotometry, magnetic susceptibility measurement and percentage metal analyses. The zones of inhibition and minimum inhibitory concentrations of the compounds against eight microbes were studied. The results obtained indicated an octahedral geometry for the Cr(III) complexes, indicative of additional coordination of two water molecules. On the other hand a square pyramid geometry was obtained for the binary oxovanadium complex and its 1,10-phenantroline adduct. However</span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">,</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> for the oxovanadium ethylenediamine adduct a distorted octahedral geometry was proposed. The result for the antibacterial studies indicated that both mixed ligand complexes of 1,10-phenantroline exhibited good antibacterial activity, and in some cases better activity than the standard, streptomycin.</span></span></span>
基金the Natural Science Foundation of Shanxi Province!991054
文摘The morphology of ZA-27 alloy reinforced by RE compounds and its wear-resistance were studied. It is found that some nodular second phases appear due to the addition of Si and RE, which can disperse in grain boundaries or between dendrite crystals so that the alloy has been refined. Energy spectrum analysis of scanning electron microscope shows that the second phases are complex compounds containing RE, Al, Zn and Si. The micro- hardness test indicates that micro-hardness values of the compounds are higher than those of the matrix. The wear-resis tance of ZA-27 alloy reinforced by RE compounds is 4 times as high as that of ZA-27 alloy and also higher than that of ZA-27 alloy containing Si phase. The impact toughness of the alloy containing RE and Si is higher than that of the alloy containing Si.