平面编织复合材料细观力学分析的一个双向直波纹模型

作为对平面编织复合材料弹性质预测的单向直波纹模型的改进，本文提出一个双向的，在经线和纬线方向上均衡的直波纹模型，它更为符合编织复合材料微结构特点。采用这个新模型和经典层板理论，通过对模型上，下表面的两种极限约束条件，予测了平面编织复合材料层板弹性常数的界限。结果表明，这个模型所予测的值更为准确，合理。     

在中医院校开设《元素医学》选修课教学的实践与效果

在高等院校中特别是医药院校开设元素与健康教学更具有内涵及深远意义。为促进微量元素与人体健康研究，培养具有渊博知识和高素质人材，有利于国民经济建设，有利于医疗保健事业，有利于振兴祖国医学事业的发展。广西中医学院，在广西高校率先开设《元素医学》选修课教学，采用多媒体软件教学方法，深受广大师生的欢迎。     

Crystal Structure and Characterization of a Dye with Two-photon Pumped Frequency-upconverted Lasing Properties

ＩｎｔｒｏｄｕｃｔｉｏｎＯｖｅｒｔｈｅ ｐａｓｔｓｅｖｅｒａｌｙｅａｒｓ,ｏｒｇａｎｉｃｍｏｌｅｃｕｌｅｓｅｘｈｉｂｉｔｉｎｇａｓｉｇｎｉｆｉｃａｎｔｔｗｏ ｐｈｏｔｏｎａｂｓｏｒｂａｎｃｅａｎｄｓｕｂｓｅｑｕｅｎｔｕｐ ｃｏｎｖｅｒｔｅｄｆｌｕｏｒｅｓｃｅｎｃｅｈａｖｅａｒｏｕｓｅｄａｎｉｎｔｅｎｓｅｉｎｔｅｒｅｓｔｄｕｅｔｏａｗｉｄｅｖａｒｉｅｔｙｏｆａｐｐｌｉｃａｔｉｏｎｉｎ ｃｌｕｄｉｎｇｔｗｏ ｐｈｏｔｏｎｕｐ ｃｏｎｖｅｒｔｅｄｌａｓｉｎｇ[1] ,ｔｗｏ ｐｈｏ ｔｏｎｏｐｔｉｃａｌｐｏｗｅｒｌ…     

流动注射化学发光法测定头孢他啶

在碱性条件下,头孢他啶对金纳米粒子催化高锰酸钾氧化鲁米诺化学发光体系的发光强度具有明显的增敏作用,基于此建立了一种测定头孢他啶的化学发光方法.在优化实验条件下,用该法测定头孢他啶的线性范围为3.0×10-5～5.0×10-2 g/L,检出限为1.0×10-5 g/L,相对标准偏差为2.0%(ρ=4.0×10-3 g/L...     

磷钨酸改性蒙脱土-离子液体修饰电极上百草枯的电化学行为及测定

该文制备了磷钨酸改性蒙脱土-离子液体修饰电极(PTA-MMT-[BMIM]PF6/GCE),用红外光谱对PTA-MMT和[BMIM]PF6进行了表征.通过对比改性前后电极的交流阻抗图,发现PQ在PTA-MMT-[BMIM]PF6/GCE上电荷转移的电阻最小.研究了百草枯(PQ)在该修饰电极上的循环伏安行为.结果表明,在...     

多组分磷脂巨囊泡的相结构和胆固醇对微畴成长的影响

巨囊泡作为细胞的简化模型,其相分离与出芽动力学规律已引起许多领域科学家的关注.本实验采用DPPC/DOPC/Chol的三组分形成的巨囊泡作为模型,借助荧光显微镜观察该三组分体系侧向分离的相结构图,并对微畴的成长过程作了系统的观察研究和理论分析.实验发现:从高温的均相区域淬灭到低温的分相区域,膜表面发生侧向分离形成微畴.体系内胆固醇的掺入量的多少会影响磷脂膜的相结构和膜内微畴的成长,固定DOPC/DPPC为1:1的前提下,微畴尺寸随着胆固醇掺入量的增加而变大.     

Regioselective Synthesis of Amino Substituted Indazolo[2,1‐b]phthalazine‐triones and Pyrazolo[1,2‐b]phthalazine‐2‐carbonitriles Catalyzed by 2‐1′‐Methylimidazolium‐3‐yl‐1‐ethyl Sulfate

The regioselective reactions of luminol with 1,3‐cyclohexanedione (or malononitrile) and aromatic aldehydes catalyzed by 2‐1′‐methylimidazolium‐3‐yl‐1‐ethyl sulfate were developed to synthesize 7‐amino‐3,4‐dihydro‐2H‐indazolo[2,1‐b]phthalazine‐1,6,11(13H)‐triones and 3,9‐diamino‐5,10‐dihydro‐5,10‐dioxo‐1H‐pyrazolo[1,2‐b]phthalazine‐2‐carbonitriles in good to excellent yields in short times.     

指数型谐振管内非线性声场的模拟研究

采用气体动理学方法模拟研究五种不同驱动强度下,=0的圆直热声谐振管和=2 2的指数型热声谐振管内的非线性声场特征。研究发现:指数型管能抑制激波及声饱和现象,但管内会出现尖峰现象。尖峰处的压力波形发生了畸变;它们是非线性的能量传递与各种耗散的竞争过程中产生的不同形态的波特征;当活塞驱动位移幅值400μm时,指数型管内压力振幅增长速度明显下降。     

Ionic liquid‐based microwave‐assisted extraction for the determination of flavonoid glycosides in pigeon pea leaves by high‐performance liquid chromatography‐diode array detector with pentafluorophenyl column

In this study, an ionic liquid‐based microwave‐assisted extraction (ILMAE) followed by high‐performance liquid chromatograph y ‐diode array detector with a pentafluorophenyl column for the extraction and quantification of eight flavonoid glycosides in pigeon pea leaves is described. Compared with conventional extraction methods, ILMAE is a more effective and environment friendly method for the extraction of nature compounds from herbal plants. Nine different types of ionic liquids with different cations and anions were investigated. The results suggested that varying the anion and cation had significant effects on the extraction of flavonoid glycosides, and 1.0 M 1‐butyl‐3‐methylimidazolium bromide ([C4MIM]Br) solution was selected as solvent. In addition, the extraction procedures were also optimized using a series of single‐factor experiments. The optimum parameters were obtained as follows: extraction temperature 60°C, liquid–solid ratio 20:1 mL/g and extraction time 13 min. Moreover, an HPLC method using pentafluorophenyl column was established and validated. Good linearity was observed with the regression coefficients (r²) more than 0.999. The limit of detection (LODs) (S/N = 3) and limit of quantification (LOQs) (S/N = 10) for the components were less than 0.41 and 1.47 μg/mL, respectively. The inter‐ and intraday precisions that were used to evaluate the reproducibility and relative standard deviation (RSD) values were less than 4.57%. The recoveries were between 97.26 and 102.69%. The method was successfully used for the analysis of samples of pigeon pea leaves. In conclusion, the developed ILMAE‐HPLC‐diode array detector using pentafluorophenyl column method can be applied for quality control of pigeon pea leaves and related medicinal products.     

复合外场中磁光材料(BiTm)_3(FeGa)_5O_(12)薄膜畴壁运动特性的研究

通过对 (BiTm) 3 (FeGa) 5O12 膜施工加低频交变磁场 ,匀速率增加的直流磁场和同时对该膜施加这两种磁场 (复合外场 ) ,用照相划线读数方法和通过电荷耦合器件 (CCD) 计算机作数字化处理获得磁畴壁 (DW)的相对百分数。结果表明 :( 1 )复合外场下DW运动规律中存在交互作用项 ;( 2 )低频交变磁场幅值 ( 1 4 0A/m)远低于等效阻力场 ( 1 0 3 A/m)时 ,DW可以运动 ,但不同步 ,频率大于 1Hz时明显滞后 ,( 3 )利用图像转换有利于提高实验结果的分辨率。