一维链状锰配位聚合物的合成、晶体结构及热稳定性研究

A manganese coordination polymer, [Mn(C₇H₂I₃O₂)₂(CH₃OH)₂]_n was synthesized and characterized by the element analysis, IR, TG and single crystal X-ray diffraction structure analysis. The title complex crystallizes in monoclinic system with space group P2₁/c, a=0.461 66(9) nm, b=1.716 6(3) nm, c=1.647 5(3) nm, β=91.84(3)°, and V=1.305 2(4) nm³, Z=2, R=0.026 2, wR=0.063 4. Each manganese(Ⅱ) ion exists in an octahedral geometry with four O atoms from three different triiodobenzoate groups and two O atoms from two methanol molecules. Two adjacent manganese(Ⅱ) atoms are bridged by two triiodobenzoate groups in bis-monodentate mode, constructing a one-dimensional chain structure along a axis, with the adjacent Mn…Mn distance being 0.461 7(5) nm. Moreover, the weak interactions between the iodine atoms lead to a three-dimensional supramolecular network. CCDC: 666558.     

微波等离子体原子发射光谱法测定交联淀粉中磷含量

采用微波等离子体原子发射光谱法,以氩气为工作气体和载气,氧气为屏蔽气,测定了交联淀粉中磷含量.试验表明:测试溶液的酸度应保持在0.03 mol·L-1以下,且预先将样品充分洗涤,除去共存的钠离子.在最佳试验条件下测定了磷的检出限、精密度、加标回收率.结果表明:波长为253.565 nm的分析谱线具有最高的灵敏度;载气和工作气为氩气,流量分别为1.5,0.27 L·min-1时,分析线253.565 nm的强度最高.测得磷的检出限(3S/N)为0.02μg·L-1.此方法测得结果的准确度和精密度与电感耦合等离子体原子发射光谱法相当,而从节能和降低成本方面考虑此方法有更好的应用前景.