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171.
本文通过引用国家的相关规定,结合公文写作的教学实践,对公文标题的准确拟写进行探讨,对进一步规范公文标题具有一定的指导意义。 相似文献
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标题化合物可在微波辐射下以良好的产率经一锅法合成,为2-氨基-4H-吡哺类化合物的制备提供了一种快速便捷的有效方法。 相似文献
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提出了一种无人机载光电吊舱在高误码率信道条件下操控指令传输策略。该传输策略通过连续重传机制保证了操控指令传输的可靠性,并依靠序号标记机制避免了重复响应。在误码率为0.01的情况下,操控指令数据包长度由20字节减少到10字节,可以将丢包率由0.85减小为0.65,正确接收一个数据包平均所需要的最少传输次数由8次大幅减少到3次。采用该传输策略保证了光电吊舱对操控指令的正确接收,降低了操控延迟,避免了重复响应。 相似文献
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An aminophenol ligand, N,N,N'-tri(2-hydroxy-5-methylbenzyl)-l,2-ethanediamine, was prepared through the Marmich reaction, and structurally characterized by NMR, IR, MS and single-crystal X-ray diffract... 相似文献
176.
A new coordination polymer, namely [Ca(HOABDC)]n(1, H3 OABDC = 5-oxyacetateisophthalic acid), has been synthesized through hydrothermal reactions of Ca(NO3)2 and H3 OABDC. The title compound crystallizes in monoclinic, space group P21/c with a = 4.3043(2), b = 21.4959(11), c = 10.7450(6) A, β = 91.411(5)o, V = 993.88(9)A3, C10H6O7 Ca, Mr = 278.23, Z = 4, Dc = 1.859 g/cm3, F(000) = 560, μ = 0.659 mm-1, the final R = 0.0328 and wR = 0.0670 for 1469 observed reflections(I 2A(I)). Single-crystal X-ray structural analysis reveals that compound 1 features 1D Ca(Ⅱ)-carboxylate chain-shaped subunits, which are further connected together via HOABDC2- ligands into a 3D(6,6)-connected nia-type hybrid framework. Moreover, the luminescent property and thermal stability of 1 were also investigated. 相似文献
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Coumarin derivative 3-bromo-7-methyloxy-4-methylcoumarin(C11H9BrO3) was synthesized and characterized by FT-IR,1H NMR spectra,and thermal analysis.The crystal structure was determined by X-ray single-crystal diffraction.The title compound crystallizes in the mono-clinic system,space group P21/n,with a = 7.770(16),b = 12.501(3),c = 10.627(2),β = 98.46(3)°,Mr = 269.09,V = 1021.0(4) 3,Z = 4,Dc = 1.751 g/cm3,μ = 4.008 mm-1,F(000) = 536,R = 0.0650 and wR = 0.1463.The optimization of the title compound was obtained by quantum chemical method at the SVWN5/6-31G** level.In the structure,the measured angles of the crystal structure are similar to those calculated,while the measured bond lengths are shorter than the calculated values due to the crystal field which functions to the molecule.The title compound also shows good fluorescent behaviors and good linear relationship with the equal concentration gradient in methanol. 相似文献
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《化学分析计量》2014,(4):7
<正>1报道范围分析测试技术,计量行业的法规、政策、标准,标准物质的研制及应用,分析、计量仪器的新产品、新技术、新方法,仪器检定、使用、维修经验,相关专业管理技术、文献综述、专题讲座、专题评论、发展动态及相关信息等。2投稿要求(1)文章重点突出,条理清楚,语句通顺,文字简练,数据可靠,结论恰当,避免重复、繁琐,不用口语、俗语等。全文包括图表在内字数一般在5 000~10 000字为宜。(2)题名应准确、简洁、鲜明,一般不超过20个汉字。作者单位包括全称、所在地、邮编。若作者出自多个单位,应按作者标注的顺序分别列出,在各自单位名称前加"1."",2."",3."。 相似文献
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Malik Aman Ullah Muhammad Adeel Muhammad Nawaz Tahir Muhammad Raza Shah Irfan Ullah 《结构化学》2014,(1):90-96
The title compounds 3-(3,5-bis(trifluoromethyl)phenyl)quinoline (1) and 3-(4- fluoro-3-methylphenyl)quinoline (2) were synthesized through Suzuki-Miyaura Cross coupling reaction of 3-bromoquinoloine with aryl boronic acids. The title compounds were characterized by single-crystal X-ray diffraction, 1H NMR, 13C NMR, El-MS, elemental analysis and IR. The crystals of 3-(3,5-bis(trifluoromethyl)phenyl)quinoline (C17H9F6N, Mr = 341.25) belongs to the monoclinic system, space group P21n, a = 12.3072(13), b = 4.9378(6), c = 24.493(2) A, V= 1473.1(3) A3, Z = 4, Dc = 1.539 Mg m-3, 2 - 0.71073A, μ = 0.144 mm^-1, F(000) = 688, the final R = 0.0715 and wR = 0.1873 for 1875 obserwed reflections with I 〉 2σ(I) and the crystal of 3-(4-fluoro-3- methylphenyl)quinoline (C16H12FN, Mr= 237.27) belongs to the orthorhombic system, space group Pca21, a = 23.794(2), b = 3.9094(3), c = 25.669(2) A, V = 2387.7(4) A3, Z = 8, D, = 1.320 Mg m-3, 2 = 0.71073 A, μ = 0.088 mm-1, F(000) = 992, the final R = 0.0534 and wR = 0.1188 for 2270 observed reflections with I 〉 2σ(I). 相似文献
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A new thiosemicarbazone compound derived from 1-phenyl-3-methyl-4-(2-thenoyl) pyrazolone-5 (HPMTP) and thiosemicarbazide has been synthesized and characterized by IR, H- NMR, MS, elemental analysis, UV and single-crystal X-ray diffraction. The compound crystallizes in monoclinic system, Cc space group with a = 7.5925(8), b = 20.263(2), c = 11.4669(13) A, r= 107.825(8)°, V = 1679.5(3) A3, Z = 4, R = 0.0316 and wR = 0.0687. The results of antibacterial activity test against Escherichia coli and Bacillus subtilis indicate that the compound possesses the same antibacterial activity as the contrast (Norfloxacin). Theoretical study of the forming mechanism to the title compound at the RHF/6-31G(d) level shows that there are two steps. The distal amino group of thiosemicarbazide is added to the 4-carbonyl group of HPMTP which forms TM. Then a dehydration reaction occurs in TM and generates a stable product PC. 相似文献