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Chen  Chao-Yue  Qiao  Yu  Zhang  Lei  Wang  Xin  Yang  Ting-Hai 《Research on Chemical Intermediates》2020,46(9):4079-4089
Research on Chemical Intermediates - When synthesizing cyclohexane-annulated pyrazolones from a cyclohexonedicarboxylate derivative with phenylhydrazine under the catalysis of sulfuric acid in the...  相似文献   
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本文报道了一个新的有机膦酸铜化合物:Cu(O3PC6H4COOH)(1).该化合物具有新型层状结构,由扭曲平面结构的{CuO4}共边形成的二核单元通过{CPO3}四面体连接起来,形成一个含有4-,8-,和14-元环的无机层.苯甲酸基团通过中等强度的氢键连接起来.并填充在层与层之间.磁性表征显示铜离子之间存在反铁磁性相互作用.化合物1的晶体属单斜晶系,C2/c空间群.  相似文献   
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庄韦  魏玮  杨廷海  孙小强 《光谱实验室》2011,28(6):2878-2881
以甲醛溶液、尿素、亚磷酸三甲酯为原料合成了N,N'-二甲基磷酰基脲,确定了最适加料方式、投料比例、反应温度及反应时间等条件.并通过红外光谱,1H NMR等对该化合物进行结构鉴定.在热重分析中该化合物显示出优异的热稳定性和较好的成炭性,可作为阻燃剂使用.  相似文献   
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1-乙基-4-氧-7-甲基-1,8-萘啶-3-羧酸的合成   总被引:1,自引:0,他引:1  
乙基氧甲基萘啶羧酸;缩合反应;成环反应;乙基化反应;水解反应;光谱特征  相似文献   
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An improved synthesis for 4,4-dimethylxanthotoxol 2,3,4,6-tetra-O-acetyl-β-D-glucoside (1) starting from resorcinol was developed. Crystallographic analysis of glucoside 1 indicated that the dihedral angles between the mean planes of the tricyclic ring system of adjacent molecules was 54.820(22)° probably due to the steric hindrance caused by the bulky O-glucoside moiety, which prevents the molecules from packing via π···π stacking between the tricyclic cores. The antifungal screening data revealed that glucoside 1 had higher inhibition than its parent compound 4,4-dimethylxanthotoxol and azoxystrobin against Rhizoctonia solani, Pyricularia grisea, and Alternaria alternate Japanese pear pathotype, with the inhibitory rates of 75.4, 65.7 and 70.1%, respectively, at the 50?µg/mL concentration.  相似文献   
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用1,4,7,10,13-五氮十五烷(cpad)作为端基配体,合成了2个同构化合物[{Ni(cpad)}3M(CN)6]2[M(CN)6](ClO4)3·6H2O (M=Cr3+,1;Fe3+,2),其中[M(CN)6]3-通过氰基桥联配位,4个[Ni(cpad)]2+阳离子形成四核簇[{Ni(cpad)}3M(CN)6]3+,游离的[M(CN)6]3-和ClO4-为平衡阴离子。晶体参数如下:1,三方晶系,P3c1空间群,a=1.5144 1(18) nm,c=3.080 7(6) nm,V=6.118 9(15) nm3,Z=2;2,三方晶系,P3c1空间群,a=1.4976 2(17) nm,c=3.087 8(5) nm,V=5.997 6(14) nm3,Z=2。变温磁化率显示在四核簇内氰基桥联的金属离子之间存在铁磁相互作用。  相似文献   
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Reactions of lanthanide nitrate, oxalate sodium and 2-pyridylmethylphosphonic acid (2-pmpH2) under hydrothermal conditions result in five new lanthanide oxalatophosphonates with two types of structures. Compounds [Ln4(ox)5(2-pmpH)2(H2O)7]·5H2O [Ln3+=Gd (1), Tb (2), Dy (3); ox2−=C2O42−] exhibit a double layer structure, made up of net-like {Ln4(ox)5}n layers containing Ln10(ox)10 rings which are connected by 2-pmpH. While compounds [Ln4(ox)5(2-pmpH)2(H2O)6]·6H2O [Ln3+=Ho (4), Yb (5)] display a three-dimensional framework structure in which the {Ln4(ox)5}n layers are cross-linked by 2-pmpH. The solid state luminescent and magnetic properties are investigated.  相似文献   
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A series of Bi3+-doped YAG:Ce3+, Mn2+ ceramics was synthesized successfully by gel-casting method and structurally characterized by XRD and SEM. The doping effect and related mechanism of Bi3+ upon the luminescent property were studied. It can be assigned to the energy transfer of multipolar interaction from Bi3+ to Ce3+, leading to the improvement of emission intensity about 58% for 0.0001 Bi3+ and 0.05 Mn2+ doping. In addition, the emission is significantly red-shifted with the peak at 590 nm for the Y2.9939 Ce0.006 Bi0.0001 Al4.96 Mn0.02 Si0.02 O12 ceramic specimen with in-line transmittance 81.6% at 1100 nm. The LED module assembled from Y2.9939 Ce0.006 Bi0.0001 Al4.96 Mn0.02 Si0.02 O12 ceramic owns correlated color temperature(CCT) of 3960 K and luminous efficiency(LE) of 92 lm/W, implying that doping Bi3+ shows a good sensitization effect in the YAG:Ce3+, Mn2+ ceramic system and further serving as an attracting phosphor candidates for warm WLEDs applications.  相似文献   
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我国青少年“笑气”滥用问题日趋严峻,引发社会关注。介绍了“笑气”的简要历史、制备方法、结构与性质、重要应用、滥用原因及危害等,期望引导青少年全面了解“笑气”,科学使用“笑气”,提早构筑起心理防线,自觉抵制“笑气”滥用。  相似文献   
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