Clinical effects research of the excision of pterygium combined with limbal epithelial autograft with conjunctival grafting on recurrent pterygium

AIM: To observe the clinical effects of the excision of pterygium combined with limbal epithelial autograft with conjunctival grafting on recurrent pterygium. <p>METHODS: Totally 84 patients(84 eyes)with first recurrent pterygium were allocated two groups: excision pterygium with limbal epithelial autograft with conjunctival(group A, 43 cases with 43 eyes)and excision of pterygium with conjunctival autograft(group B, 41 cases with 41 eyes), the post-operative follow-up period of 12 months, we analyzed the repair time of epithelium, tear break-up time(1 month and 3 months), Schirmer l test(1 month and 3 months), corneal fluorescence staining test(1 month and 3 months), and recurrent rate. <p>RESULTS: The group A had a shorter repair time of epithelium and lower recurrent rate, compared with the group B, which had statistically significant difference(<i>P</i><0.05), but there was no statistically significant difference in the tear break-up time, corneal fluorescence staining test and the Schirmer l test in 1 month and 3 months between the two groups(<i>P</i>>0.05). <p>CONCLUSION:Limbal epithelial autograft with conjunctival transplantation is a convenient, safe, effective method for the treatment of recurrent pterygium

The structural evolution of thin multi-walled carbon nanotubes during isothermal annealing

ArticleCARBON. 45(2): 274-280 (2007)journal articl

Characterization of magnetic properties of Sr2CuWO6 and Sr2CuMoO6

In this work we examine the low-temperature magnetic properties of the two double-perovskite compounds Sr2CuWO6 and Sr2CuMoO6 using magnetic susceptibility, muon spin rotation and relaxation, and neutron powder diffraction measurements. Additionally, the most relevant spin exchange interaction constants are derived from ab initio electronic structure calculations, aided by x-ray absorption spectroscopy. The compounds exhibit quasi-two-dimensional magnetic properties, with broad maxima at Tmax = 83 and 95 K for Sr2CuWO6 and Sr2CuMoO6, respectively. However, three-dimensional long-range order takes place below TN = 24(1) and 28(2) K for Sr2CuWO6 and Sr2CuMoO6, respectively. Our results show that the low-dimensional magnetic correlations are mainly due to the significant next-nearest-neighbor interactions in the ab plane of the double-perovskite structure, whereas three-dimensional long-range magnetic order is caused by weaker next-nearest-neighbor interactions along the c axis. Next-nearest-neighbor interactions are also slightly frustrated by weaker nearest-neighbor interactions within the ab plane. Based on these results we predict the low-temperature magnetic structure in these compounds to be type-II antiferromagnetic order of the double-perovskite lattice.Peer reviewe

Removal of entrapped iron compounds from isothermally treated catalytic chemical vapor deposition derived multi-walled carbon nanotubes

ArticleCARBON. 46(3): 391-396(2008)journal articl

Superconductivity Induced by Site-Selective Arsenic Doping in Mo5_5Si3_3

Arsenic doping in silicides has been much less studied compared with phosphorus. In this study, superconductivity is successfully induced by As doping in Mo$_5$Si$_3$. The superconducting transition temperature ($T_c$) reaches 7.7 K, which is higher than those in previously known W$_5$Si$_3$-type superconductors. Mo$_5$Si$_2$As is a type-II BCS superconductor with upper and lower critical fields of 6.65 T and 22.4 mT, respectively. In addition, As atoms are found to selectively take the 8$h$ sites in Mo$_5$Si$_2$As. The emergence of superconductivity is possibly due to the shift of Fermi level as a consequence of As doping, as revealed by the specific heat measurements and first-principles calculations. Our work provides not only another example of As doping, but also a practical strategy to achieve superconductivity in silicides through Fermi level engineering.Comment: Supporting Information available at the corresponding DO