反相高效液相色谱法测定维格列汀

建立反相高效液相色谱法测定维格列汀的含量。采用Venusil MP C18色谱柱（250mm×4.6mm,5μm）,流动相为磷酸盐缓冲溶液(称取20mmol·L^-1磷酸二氢钾,用85%浓磷酸调至pH3.0)-乙腈（88:12,V/V）,检测波长为210nm,流速为1.0mL·min^-1,柱温为25℃。维格列汀在5—500μg·mL^-1范围内与峰面积呈良好的线性关系（r=0.9999）,维格列汀的平均回收率为102.0%,RSD为2.65%。方法准确、简便,适用于维格列汀的定量分析。     

Supramolecular assembly of three d~(10) metal coordination polymers based on the naphthalene-1,8-dicarboxylate ligand:Syntheses,structures and luminescent properties

Three d10 tetranuclear complexes,Cd 4(1,8-nap) 4(2,2′-bipy) 4(H2O) 8·6H2O(1,8-nap=naphthalene-1,8-dicarboxylate and 2,2′bipy=2,2′-bipyridine)(1),Cd4(1,8-nap) 4(2,2′-bipy) 4(H2O) 8·6H2O(2) andZn4(1,8-nap) 4(2,2′-bipy) 4(H2O) 4·2H2O(3),have been synthesized under hydrothermal conditions and characterized by elemental analyses,IR and X-ray diffraction techniques. Complexes 1 and 2 are isomers showing one-dimensional ribbon-like structures connected by O-H···O hydrogen bonds,and the one-dimensional ribbons are ...     

特异材料吸收体的透射线模型与场分析:理想的电磁波浓缩器(英文)

Arising from the proposed Transmission Line(TL) model for ERR and wire structure, a TL model for a metamaterial absorber is proposed. The S-parameters obtained by this TL model demonstrate the same shapes as the simulation. An investigation of the TL model and average absorption power densities shows that the metamaterial absorber does not simply convert the electromagnetic wave into thermal energy, but concentrate the electromagnetic wave into a small space where it is finally absorbed. This suggests that ...     

高效液相色谱-串联质谱法测定动物血浆中罗匹尼罗的浓度

建立高效液相色谱-串联质谱(LC-MS/MS)测定动物血浆中罗匹尼罗浓度的方法。血浆经乙酸乙酯萃取后,以HPLC分离,电喷雾离子化(ESI~+)串联质谱检测。以甲醇-乙腈-0.1‰冰醋酸(36:9:55)为流动相,流速为0.2mL·min~(-1),采用Ultimate XB-C 18柱(150mm×2.1mm,3μm)分离,在三级四极杆串联质谱中经电喷雾电离源(ESI)离子化,以多反应监测(MRM)方式进行检测。盐酸罗匹尼罗、盐酸苯海拉明(内标)的扫描离子对m/Z分别为261→114和m/Z 256→167。LC-MS/MS测定血浆中罗匹尼罗线性范围为0.02—400ng·mL~(-1),范围内线性关系良好(r=0.9998);以3个浓度水平的质量控制样品求得各浓度水平日内、日间精密度(RSD)均小于15.2%。在非临床药代动力学研究中,应用此法测定了受试兔子血浆中罗匹尼罗的浓度。该法灵敏、快速、准确,操作简便,样品处理方便,线性范围宽,该方法检测快速、专一、灵敏,可满足罗匹尼罗临床前药代动力学研究和临床药动学研究的要求。     

微波消解ICP-AES测定黑番茄中的17种微量元素

采用微波消解法对样品进行处理,以电感耦合等离子体-原子发射光谱法(ICP-AES)测定黑番茄中17种微量元素的含量。方法的回收率在93.0%—105.8%之间,相对标准偏差小于2.608%。实验证明,黑番茄含有丰富的对人体有益微量元素,是一种健康食品。     

方波激发下Er~(3+)上转换红光激发机理的研究

用方波电源驱动808 nm激光二极管(LD)激发Er3+掺杂的亚碲酸盐氟氧化物玻璃,测量4F9/2能级上转换发光的上升和衰减,根据上升的时间常数确定中间能级的寿命,从而确定4F9/2能级粒子数积累的过程。通过建立速率方程模型分析4F9/2能级的上升和衰减特性与中间能级的关系,确定808 nm LD激发下上转换红光的激发机理,同时提供了一种通过上转换发光,用光电倍增管测量红外能级寿命的方法。     

外来物种紫茎泽兰光谱特征

紫茎泽兰是一种有毒的外来物种,对我国经济和环境产生了深远的影响。紫茎泽兰具有分布广、扩散快的特征,使得传统监测手段显得捉襟见肘。文章在分析了紫茎泽兰光谱特征的基础上,尝试建立紫茎泽兰遥感识别模型,旨在挖掘有效的紫茎泽兰空间分布动态监测方法。研究表明:紫茎泽兰光谱曲线在可见光范围内有2个反射峰和1个吸收谷,对应的波长分别为560,730和674 nm。紫茎泽兰在674 nm的吸收深度为0.504 3～1.910 3,吸收宽度为13.778 9～17.2518 nm,中心吸收波段的左右面积呈左偏型,且左边面积与右边面积的比值为1.771 9～2.444 1。紫茎泽兰白色的花使光谱反射率在可见光范围内有一明显的抬升,并导致一阶微分光谱在420 nm产生一个波峰。与其他典型地物的光谱特征对比可知,紫茎泽兰在674 nm的吸收宽度和左右面积比值以及420 nm的一阶导数值是花期紫茎泽兰独有的光谱特征,可作为花期遥感识别与提取紫茎泽兰的重要参数。     

Cu/CuO-Graphene Foam with Laccase-like Activity for Identification of Phenolic Compounds and Detection of Epinephrine

Although great progress has been made in the advancement of nanozymes, most of the studies focus on mimicking peroxidase, oxidase, and catalase, while relatively few studies are used to mimic laccase. However, the use of nanomaterials to mimic laccase activity will have great potential in environmental and industrial catalysis. Herein, Cu/CuO-graphene foam with laccase-like activity was designed for the identification of phenolic compounds and the detection of epinephrine. In a typical experiment, the formation mechanism of Cu/CuO-graphene foam was investigated during the pyrolysis process by thermogravimetric-mass spectrometry. As a laccase mimic, Cu/CuO-graphene foam exhibited excellent catalytic activity with a Michaelis-Menten constant and a maximum initial velocity of 0.17 mmol/L and 0.012 mmol∙L^-1∙s^-1, respectively. Based on this principle, Cu/CuO-graphene foam nanozyme could differentially catalyze phenolic compounds and 4-aminoantipyrine for simultaneous identification of phenolic compounds. Furthermore, a colorimetric sensing platform was fabricated for the quantitative determination of epinephrine, showing linear responses to epinephrine in the range of 3 mg/mL to 20 mg/mL with the detection limit of 0.2 mg/mL. The proposed Cu/CuO-graphene foam nanozyme could be applied for the identification of phenolic compounds and the detection of epinephrine, showing great potential applications for environmental monitoring, biomedical sensing, and food detection fields.     

P-Al/NaX结构和酸碱性位调控对甲苯甲醇侧链烷基化性能影响

采用水热法原位合成了P-Al/NaX催化剂,然后通过浸渍NaOH对其进行酸碱性调控,并探究了它在甲苯甲醇侧链烷基化反应中的催化性能。结合X射线衍射（XRD）、X射线光电子能谱（XPS）、N₂吸附-脱附等表征及催化活性数据发现,原位负载P、Al后,合成的磷铝硅酸盐（Na₁₃Al₂₄Si₁₃P₁₁O₉₆·H₂O）结构展现出较好的甲苯甲醇侧链烷基催化活性;随着NaOH负载量的增加,乙苯和苯乙烯的选择性呈先上升后下降的趋势,当负载质量分数为9%的NaOH时,苯乙烯选择性为45.84%,乙苯和苯乙烯的收率之和达到63.08%。这可能是由于NaOH的负载有利于催化剂表面碱性的提高和酸性的降低,而高的强碱性位和弱酸性位数量有利于甲苯甲醇侧链烷基化反应的进行。