图的倍图与补倍图

计算机科学数据库的关系中遇到了可归为倍图或补倍图的参数和哈密顿圈的问题．对简单图C，如果V（D（G））：V（G）∪V（G′）E（D（G））=E（C）∪E（C″）U{vivj′｜vi∈V（G），Vj′∈V（G′）且vivj∈E（G））那么，称D（C）是C的倍图，如果V（D（G））=V（C）∪V（G′），E（D（C））：E（C）∪E（G′）∪{vivj′}vi∈V（G），vj′∈V（G’）and vivj∈（G）），称D（C）是G的补倍图，这里G′是G的拷贝．本文研究了D（G）和D的色数，边色数，欧拉性，哈密顿性和提出了D（G） 的边色数是D（G）的最大度等公开问题．     

Synthesis and separation of mellitic acid and graphite oxide colloid through electrochemical oxidation of graphite in deionized water

Electrochemical oxidation of graphite anode in deionized water at galvanostatic mode is investigated. It is found that mellitic acid and graphite oxide colloid (>20 nm) are coexisted as main products, as identified by XRD and TEM, FTIR and XPS. They can be separated successfully through several procedures. A few amounts of graphene and graphene rolls are also appeared as co-products.     

CR超导二极铁导线的3D有限元失超模拟

利用FEM软件ANSYS对德国GSI的FAIR项目的超导二极铁的超导线进行了失超模拟.该模拟形象地给出导线的失超过程,通过APDL编程可以得到失超传播速度,失超时导体的端电压随时间的变化.文章还进一步研究了导线的最小失超传播区域MPZ,失超段初始温度和电流对失超传播速度的影响.     

基于纳米金Core-satellites等离子体耦合增强效应的汞离子光纤传感器的研究

以DNA杂交双链为联接, 构建纳米金颗粒Core-satellites结构并激发等离子体耦合增强效应,利用Hg2+可与DNA中胸腺嘧啶T形成T-Hg2+-T特异性结构,研制了用于检测水中Hg2+的局域等离子体共振(LSPR)光纤传感器.待测溶液中的Hg2+能够引起富含T的DNA单链折叠,抑制DNA杂交反应,降低等离子体耦合强度,改变LSPR谐振波长.通过检测谐振波长红移变化,实现对Hg2+浓度的定量检测.本方法检测Hg2+的线性范围为5~150 nmol/L, 检出限为3.4 nmol/L (3σ). Zn2+、Mg2+、Pb2+等重金属离子对Hg2+检测无明显干扰作用.实际水样中Hg2+加样回收率为94.2%~105.4%,相对标准偏差<4.8%.     

气相色谱法检测食品工业用大孔吸附树脂有机残留量

采用气相色谱法,建立了同时检测食品工业用大孔吸附树脂中的苯、1,2-二氯乙烷、甲苯、邻二甲苯、间二甲苯、对二甲苯、氯苯、苯乙烯、二乙烯苯、丙烯腈、甲基丙烯酸甲酯等11种有机残留物的方法。色谱柱为DB-WAX毛细柱,检测器为氢火焰离子化检测器,该方法的专属性强,在所考察的浓度范围内线性相关系数均在0.99以上,最低检出限为0.002～0.008μg/mL,样品加标回收率为72.4～104.7%,稳定性、精密度和重现性的RSD分别为1.68～5.26%、1.57～6.83%、2.91～9.62%。本方法具有简便易行、准确、稳定、快速等特点。     

凤仙花植株不同部位微量元素含量的比较分析

The samples of pueraria lobata ohwi were digested by HNO3 + HClO4 .contents of the next trace elements Fe,Zn,Cu,Mn,Ca,Mg,Co,Cr,Ni,Cd,Pb and Al in the bloom,base,stem,and leaf of Impatiens balsamina have been determined by Flame Atomic Absorption method.The result show that the recovery is about 97.5%-103.2%,and the RSD<2.7%,with good accuracy and precision.The order of the content of the trace elements of high to low is as follows:leaf>stem>bloom>base.The importance of essential trace elements Zn,Fe,Mn,Cu for human each has a higher content.In addition,toxic trace elements such as lead,arsenic and cadmium are also found.     

原子吸收光谱法测定苦藠中微量元素的含量

苦藠别名小野蒜是食用地下鳞茎及嫩茎叶的野生蔬菜,属药食同源的百合科多年生草本植物.有温中散结,宽胸通阳,祛湿止痢作用~([1,2]).在食疗方面有:(1)降脂作用,且性味辛温,能温阳散结,可用来治疗高胆固醇和高血脂症.(2)降低血压的奇妙作用,常食有通阳气、宽胸的效果.     

Microfluidic System for Synthesis of Trigonal Selenium Nanowires

<正>A microfluidic system was developed for the synthesis of trigonal selenium(t-Se) nanowires,which was composed of a glass microchip coupled with a poly(methyl methacrylate)(PMMA) microchip.In the glass microchip, amorphous selenium(a-Se) colloid was prepared by reducing selenious acid with an excess amount of hydrazine at a temperature of 100℃.In the coupled PMMA microchip,a-Se was transformed into more stable t-Se seeds via sonication at room temperature.The residence time of the reactants in both microchips was optimized by varying the dimension and length of the microchannel each.The t-Se nanowires were formed by anisotropic growth of selenium crystallite during sonication and aging under the assistance ofβ-cyclodextrin(β-CD).Various stages of the nanowires' growth were investigated.The as-synthesized products were characterized by powder X-Ray diffraction(XRD),Raman spectroscopy,scanning electron microscopy(SEM),transmission electron microscopy(TEM) and selected-area electron diffraction(SAED).     

聚γ-(2-脲基噻唑)丙基甲基硅氧烷金属配合物的制备及磁学性能研究

合成了一种新的γ-(2-脲基噻唑)丙基甲基二乙氧基硅烷单体及聚硅氧烷聚合物,采用溶胶-凝胶法制备了聚硅氧烷的铜、镍金属离子的配合物,利用红外光谱、核磁共振氢谱及质谱等手段表证了其结构.并分析和讨论了它们的磁学性能.此类金属配合物在低温区,磁化率倒数与温度的关系不服从居里-外斯定律,存在着铁磁耦合,是一类有机铁磁体.另外,发现在含噻唑基团的硅氧烷链中引入5倍当量的二甲基硅氧烷链节,其居里-外斯温度增大了近2倍.     

CdTe量子点荧光法测定阳离子表面活性剂

合成了巯基乙酸(TGA)保护的水溶性发光CdTe量子点,并考察了此探针在阳离子表面活性剂十六烷基三甲基溴化铵(CTMAB)中的发光行为。根据观察到的发光猝灭效应,建立了一种简单的测定阳离子表面活性剂的方法。考察了CdTe量子点的浓度、体系酸度、反应时间及共存物质等对测定的影响。在最佳条件下,CdTe量子点发光强度与CTMAB的浓度分别在6×10-7~9.0×10-6mol/L和1.2×10-5~3.8×10-5mol/L范围内分段成线性关系。该方法用于水样的阳离子表面活性剂的测定,回收率为97%~102%。