Controlled chemical co-precipitation and solid phase synthesis,microstructure and photoluminescence of La3PO7:Eu3+ phosphors

Eu³⁺-doped oxy-phosphate (La₃PO₇:Eu³⁺) with monoclinic phase has been synthesized via solid phase and co-precipitation methods. The products present various regular morphologies after high temperature thermal treatment, such as bulk with holes, leaf-like flake, nano-rod and so on. All the phosphors exhibit the characteristic fluorescence of Eu ion, the electric dipole transition ⁵D₀→⁷F₂ of Eu³⁺ ions is dominant indicating that the sites of Eu³⁺ ions in La₃PO₇ have no the inversion center. Furthermore, the intensity of ⁵D₀→⁷F₂ increases due to the introducing of surfactant and increasing of the calcination temperature.     

纳米碳管负载铂的修饰电极对H2O2的测定

采用嵌入修饰法制得了碳纳米管负载铂修饰的浸蜡石墨电极,结果发现该修饰电极对H2O2的氧化还原都有良好的电催化性能。但对H2O2的还原有更好的催化性能。H2O2的浓度在2.5×10-6~1×10-4mol/L范围内呈现良好的线性关系;检出限为1.26×10-6mol/L。     

Studies on Zero Point of Charge and Permanent Charge Density of Mg-Fe Hydrotalcite-like Compounds

The theoretical analysis on the zero point of charge (ZPC) and charge density of colloidal particle possessing permanent charges indicates that ZPC determined directly by means of potentiometric titration (PT) should be zero point of net charge (ZPNC) and the permanent charge density (σ_P) can be obtained from the adsorption amount of H⁺ and OH^-(Γ_OH--Γ_H+) at ZPNC. ZPNC does not change with the electrolyte concentration while the zero point of variable charge (ZPVC) changes with the electrolyte concentration. When σ_P is zero, ZPNC equals to ZPVC, and only under this condition is ZPC measured directly by PT equal to ZPVC. The relationship between ZPNC, ZNVC, σ_P, the variable charge density (σ_V)5 or the total net surface charge density (σ_T) with pH or electrolyte concentration is derived.     

Role of TiO2 Nanotube on Improvement of Performance of Hybrid Photovoltaic Devices

The performance of TiO₂ nanotubes in bulk heterojunction of poly (2-methoxy-5-(2'-ethylhexyloxy)-1, 4-phenylenevinylene) (MEH-PPV)/TiO₂ nanotubes is investigated. The transport properties are studied by using the time-of-flight technique (TOF). The carrier mobilities of both holes and electrons are not improved for the MEH-PPV:TiO₂ composites compared with the pristine MEH-PPV. However, photoluminescence under the influence of the electric field indicates that the dissociation of excitons in the MEH-PPV:TiO₂ composites, which is facilitated by photoinduced charge transfer, only requires a smaller electric field.     

Open Superstring Star as a Continuous Moyal Product with B Field

In this paper, we recast the matter part of the open superstring star in the present ofa constant B field. Byusing a different coordinate representation the matter part of the open superstring star is identified with the continuousMoyal product of functions of anti-commuting variables. Fortunately we find it does not depend on the value of the Bfield.     

Chemical Potential Dependence of Dressed-Quark Propagator

A method for obtaining the low chemical potential dependence of the dressed quark propagator from an effective quark-quark interaction model is developed. Of particular interest here is to give a generalrecipe to find without arbitrariness the solution representing the “Wigner“ phase at non-zero chemical potential for the purpose of studying QCD phase structure.     

Nonlinear Dependence of Response Rateon Intensity in Doped KNSBN Crystals

l.IntroductionThephotorefractiveresponserateisacritica1issuebecauseitdirectlydeterminestheprocessingsPeedofphotorefractivedevices[1]-TherelationshipbetweentheresPonserateandthelightintensitycanprovideusefuIinformationaboutthedefectlevels,theprocessofchargeCarriersexcited,transportedaMdtrapPed["'].Conventionalsing]elevelmod-e1s[4jpredictthatthephotorefractiveresponserateislinearlydePendentonthelightinten-sity.However,experimentaldatashowedthatthephotorefractiveresponserateofsomecrystalsvarie…     

α－甲基丙烯酸2，3－环氧丙基酯的选择性阴离子聚合

通过对α－甲基丙烯酸２，３－环氧丙基酯双键的选择性阴离子聚合的研究发现：在较低温度下（＜－４０℃），聚合中的副反应主要发生在引发阶段，以引发剂与单体中环氧基的副反应为主；当温度较高时（＞－２０℃），则易出现交联现象而难以进行双键的选择性聚合。ＧＰＣ、１ＨＮＭＲ及ＦＴＩＲ鉴定表明，在较低温度下用１，１′二苯基己基锂作引发剂可合成每个重复单元上均定量带有的环氧基的单分散（　＜１．１０）官能性聚合物，该聚合物易溶于多种溶剂。     

二元外代数的Z_n-Galois覆盖代数的Hochschild(上)同调群

设Λ是特征不整除n的域k上的二元外代数,■是Λ的Zn-Galois覆盖代数.首先构造了■的极小投射双模分解,并由此清晰地计算了■的各阶Hochschild同调和上同调群的维数;并且在域的特征为零时,计算了■的循环同调群的维数.     

Effect of a Small Current Quark Mass on Dressed Gluon and Quark Propagator

［1］C.D. Roberts and A.G. Williams, Prog. Part. Nucl. Phys.33 (1994) 477, and references therein. ［2］P.C. Tandy, Prog. Part. Nucl. Phys. 39 (1997) 117; R.T.Cahill and S.M. Gunner, Fiz. B7 (1998) 17, and references therein. ［3］R. Alkofer and L. von Smekal, Phys. Rep. 353 (2001)281; C.S. Fischer and R. Alkofer, Phys. Rev. D67 (2003)094020, and references therein. ［4］C.D. Roberts and S.M. Schmidt, Prog. Part. Nucl. Phys.45S1 (2000) 1, and references therein. ［5］P. Maris and C.D. Roberts, Int. J. Mod Phys. E12 (2003)297. ［6］R.T. Cahill and C.D. Roberts, Phys. Rev. D32 (1985)2419; C.D. Roberts, R.T. Cahill, and J. Praschiflca, Ann.Phys. (N. Y.) 188 (1988) 20. ［7］M.R. Frank and T. Meissner, Phys. Rev C57 (1998) 345. ［8］P. Maris, C.D. Roberts, and P.C. Tandy, Phys. Lett.B420 (1998) 267. ［9］M.R. Frank and T. Meissner, Phys. Rev C53 (1996) 2410. ［10］R.T. Cahill and S. Gunner, Phys. Lett. B359 (1995) 281;Mod. Phys. Lett. A10 (1995) 3051. ［11］P. Maris and C.D. Roberts, Phys. Rev C56 (1997) 3369. ［12］C. Burden, C.D. Roberts, and M. Thomson, Phys. Lett.B371 (1996) 163. ［13］C. Burden and D. Liu, Phys. Rev. D55 (1997) 367; M.A.Ivanov, Yu. L. Kalinovskii, P. Maris, and C.D. Roberts,Phys. Lett. B416 (1998) 29; Phys. Rev. C57 (1998) 1991. ［14］A. Bender, D. Blaschke, Y. Kalinovskii, and C.D.Roberts, Phys. Rev. Lett. 77 (1996) 3724. ［15］M.R. Frank, P.C. Tandy, and G. Fai, Phys. Rev. C43(1991) 2808; M.R. Frank and P.C. Tandy, Phys. Rev. C46(1992) 338; C.W. Johnson, G. Fai, and M.R. Frank, Phys.Lett. B386 (1996) 75. ［16］Xiao-Fu L, Yu-Xin Liu, Hong-Shi Zong, and En-Guang Zhao, Phys. Rev. C58 (1998) 1195; Yu-Xin Liu, DongFeng Gao, and Hua Guo, Nucl. Phys. A695 (2001) 353;Yu-Xin Liu, Dong-Feng Gao, and Hua Guo, Phys. Rev.C68 (2003) 035204. ［17］C.D. Roberts and R.T. Cahill, Aust. J. Phys. 40 (1987)499. ［18］M.R. Frank, Phys. Rev. C51 (1995) 987. ［19］T. Meissner and L.S. Kisslinger, Phys. Rev. C59 (1999)986. ［20］Hong-Shi Zong, Xiao-Fu Lu, Jian-Zhong Gu, Chao-Hsi Chang, and En-Guang Zhao, Phys. Rev. C60 (1999)055208; Hong-Shi Zong, Xiao-Fu Lui, Fan Wang, Chao-Hsi Chang, and En-Guang Zhao, Commun. Theor. Phys. (Beijing, China) 34 (2000) 563; Hong-Shi Zong, Yu-Xin Liu,Xiao-Fu Lu, Fan Wang, and En-Guang Zhao, Commun.Theor. Phys. (Beijing, China) 36 (2001) 187; Hong-Shi Zong, Xiang-Song Chen, Fan Wang, Chao-Hsi Chang, and En-Guang Zhao, Phys. Rev. C66 (2002) 015201; HongTing Yang, Hong-Shi Zong, Jia-Lun Ping, and Fan Wang,Phys. Lett. B557 (2003) 33; Hong-Shi Zong, Jia-Lun Ping, Hong-Ting Yang, Xiao-Fu Lu, and Fan Wang, Phys.Rev. D67 (2003) 074004; Hong-Shi Zong, Shi Qi, Wei Chen, Wei-Min Sun, and En-Guang, Zhao, Phys. Lett.B576 (2003) 289; Wei-Min Sun, Hong-Shi Zong, XiangSong Chen, and Fan Wang, Phys. Lett. B569 (2003) 211;Hong-Shi Zong, Xiao-Hua Wu, Feng-Yao Hou, and EnGuang Zhao, Chin. Phys. Lett. 21 (2004) 43; Wei-Min Sun, Hong-Shi Zong, Xiang-Song Chen, and Fan Wang,Int. J. Mod. Phys. A19 (2004 261; Hong-Shi Zong, FengYao Hou, Wei-Min Sun, and Xiao-Hua WU, Commun.Theor. Physics. (Beijng, China) 42 (2004) 581. ［21］P. Maris and P.C. Tandy, Phys. Rev. C60 (1999) 055214.