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本文介绍了液相烧结法合成陶瓷颜料的原理、方法和优点,为其他高纯度、纳米级无机氧化物的制备和合成提供了借鉴。 相似文献
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Vicia faba L.seedlings were hydroponically cultivated in 0-12 mg/L of extraneous lanthanum(La) for 15 d to investigate ecotoxicological effects and risk assessment of rare earth elements(REEs).The results showed that reactive oxygen species(ROS) production suchas superoxide radical(O2.-) and hydrogen peroxide(H2O2) were overproduced at higher concentrations of La,resulting in oxidatively modified proteins and shoot growth retardation.While,superoxide dismutase(SOD),catalase(CAT),ascorbate peroxidase(APX) and guaiacolperoxidase(GPX) isoenzymes were elevated to some extent to eliminate excess of ROS.HSP70 production and endopeptidase isoenzymeswere also enhanced,which were involved in repairing or degradation of the oxidatively modified proteins due to La.Thus,the antioxidantisoenzymes,endoprotease isoenzymes and HSP70 worked cooperatively to alleviate the La-induced oxidative damage.The significant enhancement of CAT and APX isoenzymes and HSP70 could also be used as early bioindicators of La-polluted solution.The threshold doserange was firstly delimited as 1-2 mg/L of extraneous La,corresponding to 7.34-9.37 μg/g dry weight in the leaves.These results would behelpful to further understand the toxicological effects and possible mechanisms of REE(s) on crop seedlings. 相似文献
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通过降低碳含量以及Cr、V微合金化设计了盘条成分,并结合热模拟试验优化了轧制工艺,成功开发了高强度高韧性预应力钢绞线盘条SWRH72BCr-1。连续冷却转变曲线(动态CCT曲线)和等温转变曲线(动态TTT曲线)模拟结果表明:在1~5℃/s的冷速下冷却生成的组织为珠光体,珠光体的最佳转变温度为575~650℃,且在625℃附近转变时间最短,6 s即可完成转变。盘条试制结果表明:盘条的显微组织主要为索氏体加少量铁素体,抗拉强度大于1200 MPa,断面收缩率大于38%,拉拔时断丝率较低。 相似文献
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邹庄煤矿为宿县矿区新建矿井,32煤层为即将开采煤层,72煤层为下一开采煤层。72煤层受岩浆岩侵蚀严重,且埋深较32煤层深,因此72煤层的瓦斯赋存情况更加复杂。文章系统分析影响瓦斯赋存的因素,采用灰色关联方法,对影响72煤层瓦斯含量的各个因素进行研究,建立了灰色关联模型,并计算出了各项因素的关联度。研究结果表明:影响邹庄煤矿72煤层瓦斯赋存的主要因素为煤的灰分、煤层埋藏深度、地层厚度、挥发分、煤厚与地层厚度比等,利用多元回归的分析方法对邹庄煤矿72煤层的瓦斯含量进行预测,并为其以后的安全开采提供前瞻性预测数据。 相似文献
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螺杆泵采油系统由于其结构简单、节能高效、调参容易、操作安全可靠等优点而被广泛应用。但是测试诊断技术的相对滞后,造成螺杆泵井的工况不能及时诊断和发现,严重影响了螺杆泵举升工艺的应用效果。因此,我们对螺杆泵井工况诊断方法进行了探讨分析,并应用到现场井实际验证,保证了油井正常生产,为螺杆泵采油系统工作参数合理调整提供了科学依据。 相似文献
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