医药中间体5-氨基-2,4,6-三碘异酞酸的制备

以间苯二甲酸为原料 ,经硝化、还原与碘化 ,合成非离子含碘造影剂的中间体 5 氨基 2 ,4,6 三碘异酞酸。 (1)硝化反应 ,n(硫酸 )∶n(硝酸钠 )∶n(间苯二甲酸 ) =7 9∶2 2∶1 0 ,温度 70℃下反应 3h ,产率为 86 7% ;(2 )还原反应 ,n(铁粉 )∶n(硝基物 ) =3 0∶1 0 ,回流反应 3h ,产率为78 1% ;(3)碘化反应 ,n(氯化碘 )∶n(氨基物 ) =3 3∶1 0 ,90℃下反应 3h ,碘化反应产率为76 2 %。每步均经改进 ,总收率为 5 1 6 % ,所得产品熔点、UV、IR、1HNMR、13CNMR等数据与文献报道一致     

Computer-Aided Search for 5-Arylideneimidazolone Anticancer Agents Able To Overcome ABCB1-Based Multidrug Resistance

ABCB1 modulation is an interesting strategy in the search for new anticancer agents that can overcome multidrug resistance (MDR). Hence, 17 new 5-arylideneimidazolones containing an amine moiety, as potential ABCB1 inhibitors, were designed, synthesized, and investigated. The series was tested in both parental (PAR) and multidrug-resistant (MDR) ABCB1-overexpressing T-lymphoma cancer cells using cytotoxicity assays. The ABCB1-modulating activity was examined in rhodamine 123 accumulation tests, followed by Pgp-Glo™ Assay to determine the influence of the most active compounds on ATPase activity. Lipophilic properties were assessed both, in silico and experimentally (RP-TLC). Pharmacophore-based molecular modelling toward ABCB1 modulation was performed. The studies allowed the identification of anticancer agents (p-fluorobenzylidene derivatives) more potent than doxorubicin, with highly selective action on MDR T-lymphoma cells (selectivity index >40). Most of the investigated compounds showed ABCB1-modulating action; in particular, two 5-benzyloxybenzylidene derivatives displayed activity nearly as strong as that of tariquidar.     

Effect of dietary selenium on the progression of heart failure in the ageing spontaneously hypertensive rat

Oxidative stress has been directly implicated in hypertension and myocardial remodelling, two pathologies fundamental to the development of chronic heart failure. Selenium (Se) can act directly and indirectly as an antioxidant and a lowered Se status leads to a higher risk of cardiovascular disease. This study examined the role of Se on the development of hypertension and subsequent progression to chronic heart failure in spontaneously hypertensive rats (SHR). Three dietary groups were studied: (i) Se‐free; (ii) normal Se (50 μg Se/kg food); and (iii) high Se (1000 μg Se/kg food). Systolic blood pressure and echocardiography were used to detect cardiac changes in vivo. At study end, cardiac tissues were assayed for glutathione peroxidase activity, thioredoxin reductase activity, and protein carbonyls. The major finding of this study was the high heart failure‐related mortality rate in SHRs fed an Se‐free diet (70%). Normal and high levels of dietary Se resulted in higher survival rates of 78 and 100%, respectively. Furthermore, high dietary Se was clearly associated with lower levels of cardiac oxidative damage and increased antioxidant expression, as well as a reduction in disease severity and mortality in the SHR.     

Dietary krill oil increases docosahexaenoic acid and reduces 2-arachidonoylglycerol but not N-acylethanolamine levels in the brain of obese Zucker rats

Evidence suggests that dietary long chain polyunsaturated fatty acids (LCPUFAs), and particularly those belonging to the n-3 family, may influence the brain fatty acid profile and, thereby, the biosynthesis of endocannabinoids in rodents. However, the doses used are usually quite high and not comparable with human intake. Recently, we have shown that relatively low doses of dietary n-3 LCPUFAs (4 weeks), in the form of either fish or krill oil, balanced for EPA and DHA content, and against a control diet with no EPA and DHA and similar contents of oleic, linoleic and α-linolenic acids, lower the concentrations of the endocannabinoids, anandamide (AEA) and 2-arachidonoylglycerol (2-AG), in the visceral adipose tissue, and of AEA in the liver and heart, of obese Zucker rats. This, in turn, is associated with lower levels of arachidonic acid in membrane phospholipids and with amelioration of some metabolic syndrome parameters. We investigated here whether in Zucker rats, under the same conditions, fish and krill oil are also able to influence LCPUFA and endocannabinoid profiles in brain. Only krill oil was able to increase significantly DHA levels in brain phospholipids, with no changes in arachidonic acid. DHA increase was associated with lower levels of 2-AG in the brain, whereas AEA and its congeners, N-palmitoylethanolamine and N-oleoylethanolamine, were unchanged. We conclude that, despite the strong impact of dietary n-3 fatty acid on endocannabinoid levels previously observed in peripheral tissues, in the brain only 2-AG is affected by dietary krill oil, suggesting that the beneficial effect of the latter on the metabolic syndrome is mostly exerted by modifying peripheral endocannabinoids. Nevertheless, possible effects of dietary krill oil in the brain through modification of 2-AG levels deserve further investigation.     

Electrochemical degradation of waters containing O-Toluidine on PbO2 and BDD anodes

Electrochemical oxidation of O-Toluidine (OT) was studied by galvanostatic electrolysis using lead dioxide (PbO₂) and boron-doped diamond (BDD) as anodes. The influence of operating parameters, such as current density, initial concentration of OT and temperature was investigated. Measurements of chemical oxygen demand were used to follow the oxidation. The experimental data indicated that on PbO₂ and BDD anodes, OT oxidation takes place by reaction with electrogenerated hydroxyl radicals and is favoured by low current density and high temperature. Furthermore, BDD anodes offer significant advantages over PbO₂ in terms of current efficiency and oxidation rate.     

间接电解氧化合成邻氯苯甲醛

采用Ｍｎ（Ⅲ）为氧化媒质，以邻氯甲苯为原料，苯做溶剂，在浓硫酸存在下，以甲丁基溴化铵为相转移催化剂，用间接电解氧化的方法合成了邻氯苯甲醛。通过正交实验考察了硫酸浓度、反应温度、反应时间、原料配比４个因素对产品收率的影响。确定最佳反应条件：硫酸浓度８．０ｍｏｌ．Ｌ＾－１，反应温度６３℃，原料配比：邻氯甲苯：「Ｍｎ＾３＋」为５：４，反应时间４ｈ，最高收率达５５％。     

A microdosimetry chamber for low-energy X rays

A wall-less proportional counter designed to measure single event spectra produced by low energy X rays is described. The sensitive volume of the counter and the housing are made entirely of non-metallic materials to minimise distortions in the secondary electron spectrum.     

Acoustic Emission Damage Assessment of Steel/CFRP Bonds for Rehabilitation

The use of adhesively bonded carbon fiber reinforced polymer (CFRP) laminates is increasingly being considered for the rehabilitation of metallic structures. The effective structural monitoring of steel/CFRP adhesive joints is of critical importance to assess the design service performance of the system, which ultimately depends on the bond damage tolerance at the load transfer regions. In the present study laboratory static and fatigue tests were conducted on steel/CFRP skin doubler and double strap joint specimens, which were monitored using the acoustic emission (AE) technique. The characteristics of the AE signals were correlated with the mechanical response of the samples, in order to understand the AE response associated with the accumulation of bond damage. One-dimensional source location was also performed to examine the initiation and the development of the disbond. The results show that AE parameter-based analysis is an effective nondestructive evaluation tool for bond damage detection and area location.     

露天矿倒堆剥离工艺的发展及其应用前景--露天矿倒堆剥离开采方法系列论文之一

露天矿倒堆剥离是一种先进的开采工艺，机械化程度高，开采成本低。对世界范围倒堆剥离用大型拉斗电铲的制造及使用现状进行了统计分析，介绍了拉斗铲的基本作业方式，分析了我国大型煤田采用倒堆剥离方法的有利条件及应用前景。     

基于多目标的半导体生产线满意调度

在分析生产线性能指标的基础上，选择出用于优化的目标，并针对基于单目标的调度策略所存在的局限性，采用满意的概念，根据模糊规则与比较法提出了基于多目标的满意调度，实验表明该调度方法较单目标调度策略有很大的优越性，从而为实现生产线的整体优化提供了解决的途径。