2种菊科植物总黄酮的抗氧化活性研究

采用有机溶剂提取2种菊科植物总黄酮。测定了黄酮提取液的还原力、抗氧化能力。结果表明:还原力强弱为Vc>小甘菊>少花粉苞菊。2种植物对自由基的抑制能力为:DPPH>O_2~-·>·OH,但是抑制油脂过氧化值的能力要低于V_c。     

响应面试验优化紫薯皮色素提取工艺及其稳定性分析

通过Box-Behnken试验设计和响应面分析法,对紫薯皮色素的提取条件进行了优化,并且研究了各种物理及化学因素对紫薯皮色素稳定性的影响。结果,得出最佳提取条件为：酸醇体积比1∶1（0.5%柠檬酸酸化）、料液比1∶60（g/mL）、提取温度50 ℃、提取时间20 min。在此优化方案条件下,理论吸光度预测值为0.843,实际吸光度为0.838。紫薯皮色素的稳定性研究结果显示：日光暴晒条件下光稳定性比较差,自然光和避光条件下,稳定性良好;4～60 ℃的温度范围内具有非常好的热稳定性;紫薯皮色素在含有K＋、Ca2＋、Na＋、Zn2＋等金属离子的溶液中表现比较稳定的状态,在含有Mg2＋、Cu2＋、Mn2＋、Fe3＋等金属离子的溶液中产生沉淀;酸性条件有利于紫薯皮色素的稳定性,而碱性条件不利于紫薯皮色素的稳定性;最大安全使用范围内,紫薯皮色素稳定性几乎不会受到苯甲酸、山梨酸等一系列常用食品添加剂溶液的影响,可作为食品着色剂。     

Effect of Vehicle and Drug Concentration on transdermal delivery of Dihydroergotamine using excised Animal Skin

Dihydroergotamine (DHE) is widely used in the treatment, of migraine as I.M. injection of 1.0 mg/ml. Absorption of DHE averaged 23% when taken orally and the drug is subjected to extensive first-pass effect. The physicochemical and pharmacokinetic characteristics of DHE such as small dose, low M.W. and extensive hepatic metabolism, suggests that this drug is a possible candidate for trans-dermal delivery.

The purpose of this study was to investigate the effect of vehicle and dose variation on the percutaneous absorption of DHE. In-vitro diffusion studies were conducted utilizing improved Franz diffusion cells. The rabbit skin obtained from the dorsal area was employed as a barrier membrane.     

Sympathetic activity and blood pressure in normotensive and hypertensive patients undergoing ophthalmic surgery under electrostimulation anaesthesia (author's transl)

Plasma adrenaline, noradrenaline, blood pressure and heart rate were determined in 10 normotensive and 10 hypertensive patients undergoing ophthalmic surgery under electrostimulation anaesthesia. Venous blood samples for the determination of the catecholamines by a spectrofluorometric method were taken 30 min after premedication and 45 min after surgical incision. The catecholamine concentrations showed no significant differences neither by comparing the normotensive patients with the hypertensive patients nor by comparing the values during operation with them after premedication in each group. However, in the hypertensive patients blood pressure showed a higher increase during operation than in the normotensive patients.     

Acidochromicity of a low‐molecular‐weight pyrimidine‐based copolymer

A new type of low‐molecular‐weight polypyrimidine in a π‐conjugated main chain was prepared by a Grignard reaction between 2‐amino‐4,6‐dichloropyrimidine and 1,4‐dibromo‐2,5‐didodecyloxybenzene in the presence of [1,2‐Bis(diphenylphosphino) ethane]dichloronickel(II). The structure of the copolymer was fully elucidated by Fourier transform infrared spectroscopy, ¹H‐NMR, and elemental analysis. The copolymer had good solubility in common organic solvents. The copolymer displayed a bathochromic shift when protonated with an organic or inorganic acid in chloroform or tetrahydrofuran. The copolymer depicted facile p‐doping and good electron‐transporting electrochemical properties in a 1M H₂SO₄ aqueous solution. The copolymer showed a narrow polydispersity of 1.04. Thermogravimetric analysis showed that the copolymer had a certain thermal stability with no decomposition at a temperature of 250°C under N₂. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 41174.     

Role of thiosulfate in susceptibility of AISI 316L austenitic stainless steels to pitting corrosion in 3.5% sodium chloride solutions

The susceptibility of AISI (American iron and steel institute) 316L austenitic stainless steel alloy to pitting corrosion was assessed in 3.5% chloride solutions containing various concentration of thiosulfate ions, a main sulfide oxidant product, spanning across values of 0.001, 0.005, 0.01, 0.05 and 0.1 M, at temperatures of 23, 50 and 80°C. The potentiodynamic scan results indicated that low thiosulfate concentrations promote the chloride attack and the aggressiveness of thiosulfate species depends on the chloride to thiosulfate ratio and the test temperature. Increasing temperature apparently promotes the ionic activity of Cl^– and S₂O₃^2– The thiosulfate to chloride ratio plays an essential role in pitting the intensity of the AISI 316L stainless steel alloy and was found to be dependent on the test temperature.     

玻璃光波导元件检测氯仿蒸汽的研究

利用旋转甩涂法在钾离子交换玻璃光波导表面上固定甲基绿/聚乙烯醇薄膜，成功地检测氯仿蒸汽。实验结果表明，该元件对氯仿蒸汽有良好的响应，其线性响应范围为10×10^-3-90×10^-3（R=0.98674）。该元件具有响应恢复速度快、可逆性好、成本低和易制备等特点。     

A Water Management Support System for Amman Zarqa Basin in Jordan

A Water Management Support System for Amman Zarqa Basin in Jordan has been developed. The water management support system employs the Water Evaluation and Planning system (WEAP). The water resources and demands in the basin were modeled as a network of supply and demand nodes connected by links. The model was calibrated for the year 2005 data and then validated for the year 2006 data. Validation results showed good agreement between calculated and measured inflows to wastewater treatment plants in the basin. The model was run for the year 2005 data as well as for four scenarios for the year 2025 which are Business As Usual (BAU) scenario, Advanced Wastewater Treatment (AWWT) scenario, the Red Sea, Dead Sea Channel (RSDSC) scenario and the optimistic scenario. The BAU scenario assumes that water use trends for the year 2025 follows predictable trends, the implementation of the disi project and the Wehda dam are main components of the BAU scenario. The AWWT scenario assumes that the effluent of As Samra wastewater treatment plant is treated to a level where it can be used for unrestricted irrigation within the basin and in the highlands. The main component of the RSDSC scenario is the implementation of the RSDSC project. The optimistic scenario combines both the AWWT scenario and the RSDSC scenario. The AWWT scenario, the RSDSC scenario, and the optimistic scenario are child scenarios of the BAU scenario. The results showed that neither domestic demand nor agricultural demand is met for the year 2005. The results also showed that domestic and industrial demands can be satisfied for all the considered scenarios by proper management of the available resources. However, agricultural demand can’t be satisfied for the business as usual scenario.