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铁路下和公路下等线性构筑物下的采煤技术探讨 被引量:2
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作者 冯殿刚 《科技与企业》 2012年第8期157-157,共1页
建筑物下采煤的防护措施是减小地表移动变形的开采措施,尽可能控制建筑物所在地表的移动变形;对建筑物采取结构措施,增加其抵抗变形能力。线性构筑物是铁路、公路、管线等。这些构筑物因延伸长度大,留设保护煤柱时压煤量大,要采取科学... 建筑物下采煤的防护措施是减小地表移动变形的开采措施,尽可能控制建筑物所在地表的移动变形;对建筑物采取结构措施,增加其抵抗变形能力。线性构筑物是铁路、公路、管线等。这些构筑物因延伸长度大,留设保护煤柱时压煤量大,要采取科学措施实施开采。本文提出了铁路下、公路下等线性构筑物下采煤的开采防护措施。 展开更多
关键词 铁路下 公路下 线性构筑物 采煤
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Synthesis, Growth, and Characterization of a New Thiourea and Bismuth Chloride Complex with Excellent Nonlinear Optical Properties 被引量:1
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作者 Liang Zhang Lina Zhou +2 位作者 Baohong Hou Qiuxiang Yin Chuang Xie 《Transactions of Tianjin University》 EI CAS 2018年第6期532-537,共6页
Crystals of a new organometallic nonlinear optical (NLO) compound, di-ta-chloro-bis[chlorotri(thiourea)bismuth(Ⅲ)]- pentachloro(thiourea)bismuth-ate(Ⅲ) (DCBPB), have been successfully grown from formic a... Crystals of a new organometallic nonlinear optical (NLO) compound, di-ta-chloro-bis[chlorotri(thiourea)bismuth(Ⅲ)]- pentachloro(thiourea)bismuth-ate(Ⅲ) (DCBPB), have been successfully grown from formic acid aqueous solutions of thio-urea and bismuth chloride by a slow evaporation technique. The crystal structure and atomic composition of DCBPB have been confirmed by single crystal X-ray diffraction (SCXRD), Fourier transform infrared spectra, and elemental analysis. The SCXRD results proved that DCBPB crystallizes in triclinic space group P1 with unit cell dimensions of a = 7.0606(2) A, b = 8.8106(4) A, c = 16.3247(8) A, a = 99.242(4)°, fl = 95.309(3)°, )/= 105.856(3)°, and Z= 2. DCBPB crystal exhibits excel-lent transmittance from 500 to 2500 nm and green fluorescence with maximum emission at 508 nm. The thermogravimetric-differential scanning calorimetry (TG-DSC) analysis indicates that a solid-phase reaction took place at 170.1 ℃, whereas the decomposition temperature of the crystal material was 189℃. The NLO property obtained by the Kurtz powder test showed that the second harmonic generation efficiency of DCBPB crystal is two-seventh of KDP crystal. 展开更多
关键词 NLO ORGANOMETALLIC THIOUREA Bismuth chloride TG-DTA
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