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81.
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83.
The nonionic surfactant properties of ethoxylated azo dyes, such as cloud point and surface tension have been investigated.
The synthesized ethoxylated azo dyes could dye polyester fabric without any special pre-treatment. When the average number
of ethylene oxide (EO) in the ethoxylated azo dye reached 6, its fixation could exceed 90% from the thermosol dyeing process.
The average degree of condensation of ethylene glycol in the chain was interrelated with the dyeing results and did not affect
on the maximum absorption wavelength (λmax) of the polyoxyethylene dye. When the average length of polyoxyethylene chain decreased,
the molecular weight of dyes became smaller and the fixation of dyes was improved. 相似文献
84.
Ivermectin, the antiparasitic drug from the macrocyclic lactones class raises attention due to its high efficiency against nematodes and arthropods and very specific toxic and side effects that it may produce in host. Dominant clinical symptoms of adverse effects and toxicity of ivermectin in animals are tremor, ataxia, CNS depression and coma which often results in mortality. In our study increasing intravenous doses of ivermectin, (6 or more times higher than therapeutic dose: 1.25, 2.5, 3.75, 5.0, 6.25 and 7.5 mg/kg), caused dose-dependent disturbance of motor coordination in treated rats. The median effective dose (ED50) that was able to impair the rota-rod performance in rats treated 3 min before testing was 2.52 mg/kg. This effect weakens over time, while in the rats treated 60 min before the rota-rod test, ED50 of ivermectin was 4.21 mg/kg. Whereas, all tested doses of ivermectin did not cause any other clinical symptoms of toxicity. Ivermectin has no effect on the contractions of isolated diaphragm caused by the EFS, which effectively blocked mecamylamine (100 μM) and pancuronium (1 and 2 μM). Effect on motor coordination is the first detectable clinical symptom of ivermectin toxicity and apparently is a result of its central effects. 相似文献
85.
江西省可持续发展动态分析 总被引:1,自引:0,他引:1
基于生态足迹理论, 提出了生态压力指数、生态占用指数和生态经济协调指数3 个概念, 并构建了可持续发展评价模型。利用该模型对江西省1990~2007 年的生态安全、消费水平、生态与经济协调发展状况进行定量研究, 结果表明: 江西省的生态压力指数从1990 年的1.56 增高到2007 年的1.96, 17 年间生态压力指数提高25.64%, 生态环境始终处于很不安全状态(2 级); 生态占用指数从1990 年的0.79 逐年提高到2007 年的0.88, 始终属于较贫穷状态(2 级); 生态经济协调指数从1990 年的0.50 逐年降低到2007 年的0.45, 始终处于很差等级(1 级); 可持续发展指数从1990 年的0.19 逐渐降低到2007 年的0.13, 始终处于很差等级(1 级)。 相似文献
86.
山地果园索道张紧调节自动控制装置的设计 总被引:7,自引:6,他引:1
为进一步提高山地果园中果品农资运输的安全性和可靠性,解决传统索道张紧调节依赖于人力或机械的方法受到使用强度限制,无法对索道运行过程中驱动链张紧进行实时检测,导致张紧调节具有滞后性、自适应不强等问题,该文设计了一种山地果园索道张紧调节自动控制装置,张紧调节采用PID控制算法,可适用于不同负载条件下,实时检测驱动链张紧力变化调整索道驱动链张紧程度。试验结果表明:索道运行过程中,张紧控制系统工作在无控制和PID控制条件下,驱动链分别承受的张紧力均值变化范围为:653.5944~763.4059 N和508.1988~568.7609 N,能有效地实现驱动链张紧自动调节,控制系统最大跟踪误差为104 N,平均误差为13.6417 N。 相似文献
87.
该文就非接触高频反射式涡流传感器用作带锯条非接触检测的电路理论和工作原理进行了分析,介绍了该仪器用于修锯行业作适张度、背弧度检测的优点. 相似文献
88.
89.
The ring spinning process has been used to produce fine and high quality staple fibre yarns. The stability of the rotating
yarn loop (i.e. balloon) between the yarn-guide and the traveller-ring is crucial to the success and economics of this process.
Balloon control rings are used to contain the yarn-loop, by reducing the yarn tension and decreasing the balloon flutter instability.
Flutter instability here refers to the uncontrolled changes in a ballooning yarn under dynamic forces, including the air drag.
Due to the significant variation in the length and radius of the balloon during the bobbin filling process, the optimal location
for the balloon control ring is not easily determined. In order to address this difficulty, this study investigates the variation
in the radius of a free balloon and examines the effect of balloon control rings of various diameters at different locations
on yarn tension and balloon flutter stability. The results indicate that the maximum radius of a free balloon and its corresponding
position depend not only on the yarn-length to balloon-height ratio, but also on yarn type and count. A control ring of suitable
radius and position can significantly reduce yarn tension and decrease flutter instability of free single-loop balloons. While
the balloon control rings are usually fixed to, and move in sinc with, the ring frame, results reported in this study suggest
that theoretically, a balloon control ring that always remains approximately half way between the yarn-guide and the ring
rail during spinning can lead to significant reduction in yarn tension. 相似文献
90.
Bola型表面活性剂磺化脱氢松香酸二钠盐的表面化学性质 总被引:1,自引:0,他引:1
以脱氢松香酸为原料,经磺化、中和反应合成了一种非对称Bola型表面活性剂磺化脱氢松香酸二钠盐(DSDA),利用FT-IR、1H NMR及MS对目标产物结构进行确证,采用表面张力法确定了DSDA在303.0K、pH值为10.5时的临界胶束浓度(CMC),考察了其在不同NaCl浓度(0~0.50mol/L)下的表面活性.结果表明,DSDA溶液表面张力-浓度曲线出现了一个转折点;一定温度下,随着NaCl浓度的增大,DSDA溶液CMC从25mmol/L降至3.83mmol/L,表面极限吸附量(Г∞)下降,最低表面张力(γCMC)基本不受影响. 相似文献