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由LED七彩莲花灯的变色同步机制受大功率电磁炉低频传导干扰的案例为出发点,首先介绍莲花灯的基本原理及其变色同步机制,然后对出现的问题进行原因分析,最后运用低通滤波器抑制电磁炉的低频传导干扰,实现七彩莲花灯稳定的变色同步。 相似文献
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甲醇和甲醛往往同时存在,为了能同时检测它们,采用变色酸光度法对甲醇、甲醛的检测进行了探讨性实验。先用变色酸比色法直接测定甲醛,然后在酸性条件下用高锰酸钾将甲醇氧化成甲醛后再与变色酸反应进行测定,这时的测定值为甲醇与甲醛之总量,扣除甲醛之量后就得到甲醇量。甲醛的最低检出浓度为2mg/L,测定上限为20mg/L,方法的精密度和准确度也比较好。 相似文献
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用变色酸法测定废水中的甲醇 总被引:5,自引:0,他引:5
目前西南油气田一些监测站尚不具备用甲醇分析气相色谱法的相应能力,因此通过比色定量分析实验,用变色酸法测定废水中甲醇。研究结果表明:标准溶液在570 nm处吸光度最大;对甲醇含量为8 μg/mL的标准溶液,显色剂最佳用量为0.5 mL。按照实验方法配制标准系列,测定、统计、回归出甲醇标准曲线。该方法对甲醇的最低检出浓度为0.080 mg/L。加标回收结果表明,该方法的准确度和精密度均较好,由此确定了用变色酸法测定废水中甲醇的最佳反应条件。 相似文献
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本文针对PVC塑料型材老化现象,从引起PVC塑料型材老化的基本观点、人工老化试验、不同地区气候老化影响、老化导致变色的影响因素等方面进行了讨论,提出了解决PVC塑料型材老化现象意见. 相似文献
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本文针对PVC塑料型材老化现象,从引起PVC塑料型材老化的基本观点、人工老化试验、不同地区气候老化影响、老化导致变色的影响因素等方面进行了讨论,提出了解决PVC塑料型材老化现象意见. 相似文献
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通过对膨润土的羟基铝改性实验大大提高了膨润土对染料废水的处理效率。实验结果表明:改性膨润土对变色酸有很好的去除效果,对H酸有较好的去除效果,对T酸处理效果一般,对吐氏酸几乎没有效果。 相似文献
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为研究在严酷环境下涂层对钢结构的防护性能,本文通过对应用于钢结构外表面、内表面以及钢支架的涂层进行了1年的现场暴露试验以及2000h的模拟加速腐蚀试验,积累了涂层在钢结构的老化数据,获取了涂层的腐蚀等级评级。结果表明:现场暴露1年后,载荷尚未产生明显的影响,所有涂层均未出现失光、变色、粉化、开裂、起泡等老化现象;经过2000h盐雾试验后,涂层表面形貌未发生明显变化,涂层未出现起泡、开裂和出锈等现象,表明涂层具有良好抗盐雾和水汽的渗透能力;经过2000h紫外老化试验后,涂层均未出现严重的老化现象,但都出现了不同程度的变色和粉化现象。 相似文献
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城镇化是推动我国经济社会发展的重要动力,在高速发展的同时,带来大量污染排放,威胁乡村环境质量与可持续发展。在对乡村生态环境问题剖析的基础上,从战略、实施、方式等层面探索解决思路,围绕科学规划、发展方式、基础建设、管理机制、宣传教育等方面分析关键点,加强乡村环境保护,保障城镇化建设健康发展,为促进农村农业持续发展提供持久动力。 相似文献
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Trametes versicolor decolorized 2000 mg L(-1) of the mono-azo substituted naphthalenic dye Amaranth with no dye sorption observed visually. The changes in the toxicity were assessed over a period of 30 d for the dye-treated viable culture, control (no dye added), and a boiled culture treated with dye, using the Microtox Acute Toxicity assay. Before dye addition, the culture filtrate had some toxicity, which increased after the dye addition. The toxicity of the dye-treated culture decreased during the treatment. The loss of toxicity occurred at the same time, with the loss of color suggesting that detoxification is associated with decoloration. The change in pH was due to natural metabolic processes and had a small effect on detoxification. Because the toxicity of the treatment was similar to that of the control at the end of the treatment, the effluent seems to be safe for release into the environment, potentially rendering this treatment suitable for industrial application. 相似文献
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泵站树状给水管网流量具有随机性,而这种随机性变化会直接影响管网的建设费用和动力费用.针对这-特点,应用随机规划原理,建立泵站树状给水管网机会约束模型,编写基于随机模拟的遗传算法程序求解该模型.机会约束模型能较客观地反映该管网的实际工况,使优化设计结果更符合实际. 相似文献
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Günay Kocasoy 《Environmental management》1989,13(4):469-475
The increase in the number of tourists visiting a coast is desired by most of the countries for economic reasons. However, this increase in tourism may cause pollution of the sea. This can be only avoided by proper planning and by predicting the carrying capacity of the coast in terms of sea pollution. This is especially important for developing countries where part of the wastewater is discharged without any treatment into the sea.In the present study the beaches were classified according to their use — and consequently the amount of waste discharged into the sea — into four groups: (1) coasts that are used only for swimming and recreational purposes; (2) coasts used simultaneously for dwelling, swimming, and recreational purposes; (3) coasts along which only dwellings exist; and (4) natural and man-made harbors, i.e., coasts used as shelters. During the survey,40,320 observations were made between December 1985 and February 1988 to determine the effect of the number of tourists on seawater quality. The results obtained were analyzed by a multilinear regression program to obtain an empirical equation giving the extent of the sea pollution in terms of coliform concentration as a function of population density and some other environmental factors.The equations derived in this study enable the determination of the carrying capacity of a beach in terms of pollution as well as the expected degree of pollution corresponding to a given population density. Furthermore, it allows the prediction of the extra carrying capacity that can be obtained by improving the waste-disposal conditions. 相似文献
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阐释了信息产业专门化街区的内涵,结合对合肥市黄山路信息产业专门化街区构成要素的分类及其邻近度的分析,分别从空间结构演化、景观演化、功能演化三方面阐述了合肥市黄山路由"电子一条街"向"信息产业专门化街区"的总体演化阶段,探讨了信息产业专门化街区的未来发展趋势。 相似文献
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