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71.
72.
碘冉酸阴离子桥联双核铜(Ⅱ)配合物的合成与磁性孟祥军寇会忠邹国彰廖代正姜宗慧*王耕霖(南开大学化学系天津300071)关键词碘冉酸,Cu(Ⅱ),双核配合物,合成,磁性1996-08-20收稿,1996-11-18修回国家自然科学基金资助项目随着生物无... 相似文献
73.
Regular Semigroups with Quasi-Ideal Orthodox Transversals 总被引:1,自引:0,他引:1
Xiangjun Kong 《Semigroup Forum》2007,74(2):247-258
We give some simple algebraic conditions on the coefficients of a boundary value problem for a differential equations of Ventcel
type, depending on a spectral parameter, which guarantee the existence, uniqueness of a solution and coerciveness estimate,
for a spectral parameter lying in some sector. 相似文献
74.
在发光层中插入无发光中心的ZnS薄膜,研究了新结构器件发光层中发光中心周围的广的分布与发光中心在薄膜中位置的关系,确定在SiO2/ZnS:Tb界面附近区域的发光中心周围有较多的F,远离该界面区域的发光中心周围的F-离子较少,前一区域的发光中心的发光亮度较低,后一区域的发光中心的发光亮度较高,并拟合出前一区域的厚度为18nm. 相似文献
75.
通过热重分析测定TC60/C70混合物的明显升华起始温度约为600℃.在高真空(10(-3)Pa)中加热C60/C70混合物使其升华,在KBr晶体上形成薄膜,对不同升华条件下所得薄膜的傅里叶变换红外光谱(FTIR)进行比较,得出了薄膜成分变化规律.发现600℃加热混合物足够长时间,能去除混合物中低碳素富勒烯杂质,再恒温700℃升华混合物,薄膜主要由C60组成. 相似文献
76.
77.
建立了夸克胶子等离子体中胶子的经典输运方程, 并讨论了它与胶子的量子输运方程以及它与夸克的经典输运方程之间的关系. 相似文献
78.
Uniform-sized molecularly imprinted polymer for metsulfuron-methyl by one-step swelling and polymerization method 总被引:1,自引:0,他引:1
Uniform-sized molecularly imprinted polymer (MIP) beads for metsulfuron-methyl (MSM) were firstly prepared by one-step swelling and polymerization method using 4-vinylpyridine (4-VPY) and ethylene glycol dimethacrylate (EDMA) as functional monomer and cross-linker, respectively. The preparation was optimized by varying the ratio of MSM to 4-VPY. The chromatographic behaviors of MSM and other structurally related sulfonylureas (SUs) on the resultant MIP column were evaluated. The imprinted polymer revealed specific affinity to the template and the fair resolution of SUs was also obtained. Furthermore, the uniform-sized MSM-MIP was used as the solid phase extraction (SPE) material to enrich MSM in real water samples before reversed-phase HPLC (RP-HPLC) analysis. The recovery of MSM from 100 mL of drinking water at a 50 ng/L spike level was 99.59% with R.S.D. of 1.13%. The detection limit was about 6.0 ng/L of MSM when enriching a 100 mL water sample. 相似文献
79.
80.
Separation in micellar electrokinetic chromatography is influenced by many factors. The separation of 9 pesticides was optimized using orthogonal array designs (OADs), five relevant factors were investigated: type and concentration of surfactant, concentration of buffer, pH and concentration of urea modifier. In the first experiment, five factors were examined at two levels using an OA16(215) matrix, by which the effect of each factor was estimated using individual contributions as response function, based on the results of the first experiment, three more important factors were chosen for further optimization using OA9(34) matrix to locate the exact levels for each variable. Finally, 9 pesticides achieved baseline-separation within 15 min. 相似文献