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详细计算了PVC生产精馏系统换热设备的热负荷、循环水量及运行成本,认为通过调整系统的运行温度和压力,精馏装置使用循环水替代7℃水具有可行性,这将有利于突破能耗高的技术瓶颈,最大程度地发挥节能降耗、减污增效的潜能。 相似文献
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Synergistic flame retardant effects of activated carbon and molybdenum oxide in poly(vinyl chloride) 下载免费PDF全文
Mengjiao Zhang Weihong Wu Shaorui He Xue Wang Yunhong Jiao Hongqiang Qu Jianzhong Xu 《Polymer International》2018,67(4):445-452
The synergistic effects of activated carbon (AC) and molybdenum oxide (MoO3) in improving the flame retardancy of poly(vinyl chloride) (PVC) were investigated. The effects of AC, MoO3 and their mixture with a mass ratio of 1:1 on the flame retardancy and smoke suppression properties of PVC were studied using the limiting oxygen index and cone calorimeter tests. It was found that the flame retardancy of the relatively cheaper AC was slightly weaker than that of MoO3. In addition, the incorporation of AC and MoO3 greatly reduced the total heat release and improved smoke suppressant property of PVC composites. When the total content of AC and MoO3 was 10 phr, PVC/AC/MoO3 had the lowest peak heat release rate and peak smoke production rate values of 173.80 kW m?2 and 0.1472 m2 s?1, which represented reductions of 47.3 and 59.9%, respectively, compared with those of PVC. Furthermore, thermogravimetric analysis and gel content tests were used to analyze the flame retardant mechanism of AC and MoO3, with results showing that AC could promote early crosslinking in PVC. Char residue left after heating at 500 °C was analyzed using scanning electron microscopy and Raman spectroscopy, and the results showed that MoO3 produced the most compact char, with the smallest and most organized carbonaceous microstructures. © 2017 Society of Chemical Industry 相似文献
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以改进的Hummers法制备还原氧化石墨烯(RGO),以RGO和碱式硫酸镁晶须(MHSHw)为填料,采用机械球磨法制备RGO/MHSHw/PVC复合粉料,经平板硫化机热压成型得三相复合板材。考察了RGO和MHSHw对复合材料电阻率、阻燃性能及力学性能的影响。结果表明:RGO具有很好的片层结构和导电性;当MHSHw添加量为5%,RGO添加量为1%时,RGO/MHSHw/PVC复合板材的表面电阻率为4×106Ω/square,比纯PVC下降8个数量级,达到了商业抗静电效果,拉伸强度达到最大值17.61 MPa,比纯PVC提高了44.04%,复合板材氧指数>33%,具有阻燃性能,得到力学性能优良兼具有抗静电和阻燃性能的复合材料。 相似文献
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采用低温水等离子体技术,在三通道聚氯乙烯(PVC)膜表面接枝了甲基丙烯氧基苄基二甲基氯化铵(DMAE)单体,增强了膜亲水和抗菌性能。通过红外分析,表明DMAE成功接枝到了PVC膜上,水通量提高两倍,PVC-ir-H2O膜(通过水等离子体处理的膜)对牛血清蛋白(BSA)的吸附能力下降67%,对BSA溶液的通量从7.7提高至40 kg?m-2?h-1,并且对BSA的截留能力不变。通过静态及动态抗菌实验,接枝后的PVC膜(PVC-g-PMAE膜)抗菌率达到100%,膜组件运行中的抗菌率也达到82%以上。在保证细菌截留率100%的同时,其渗透通量提高三倍。该膜表面修饰工程技术能实现膜表面的均一化改性,且绿色环保、操作简便、成本低,改性膜在饮用水处理领域,尤其是家用净水器中展现了很好的应用前景。 相似文献
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Marieke M. Hoog Antink Lisa Röpke Julia Bartels Christian Soltmann Andreas Kunzmann Kurosch Rezwan Stephen Kroll 《Ceramics International》2018,44(14):16561-16571
The growing demand for stony corals as ornamental aquarium animals requires defined aquacultural breeding strategies. For the sexual propagation of corals, material substrates are needed, that attract larvae and support their settlement and development. In this study, five types of highly porous ceramic materials were developed following the example of coral skeleton. The applicability of these settlement substrates was tested using larvae of the stony coral Pocillopora damicornis. Partial sintering of pressed clay pellets, freeze casting of clay and alumina-mullite based slurries and direct foaming of high alkane phase emulsified suspensions (HAPES) using alumina were employed. By the addition of mm-sized spherical polystyrene beads as sacrificial templates during freeze casting (alumina-mullite), superficial pores in the size of the larvae were created. The inorganic substrates featured open porosities between 35% (pressed clay) and 83% (foamed alumina), pore sizes ranging from nm to mm-scale and pore morphologies dominated by interparticle porosity (pressed), lamellar pores (freeze casting) and cellular pore types (direct foaming). The ceramic substrates were incubated in artificial sea water for 3 months to induce necessary biofilm formation and algae growth. Afterwards, individual substrates were exposed to 5 coral larvae, and their settlement behavior was monitored over 14 days. At the end of this period, all ceramic materials were successfully accepted as settlement substrates, with a mean settlement rate of 46.2%, and no significant differences between the substrate types. On samples with large surface superficial pores, a significantly reduced survival of settled larvae (79%) compared to the other porous materials (93–98%) was determined, suggesting a non-ideal surface topography. While alumina foam samples (HAPES) exhibit the most promising results in terms of settlement and survival of larvae, clay-based substrates provide a more economic solution for the sexual propagation of corals in aquaculture. 相似文献
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