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为研究青岛市西海岸新区近年来土地利用状况,本文利用2013年和2018年Landsat 8影像数据,采用监督分类方法提取土地利用信息,根据土地利用转移矩阵以及动态度、变化幅度等方法来分析西海岸新区的土地使用变化情况.结果表明:2013年~2018年,西海岸新区土地利用/覆被变化明显,表现为:在数量上,建设用地迅速扩张,增加74.36 km2,林地变化幅度在各类土地利用类型中最大,达到298.63%,耕地和水域变化速度相对较慢,其他用地则呈现出减少的态势;在空间尺度上,土地利用状况以老黄岛最为活跃;从土地利用转移结果上,各土地利用类型之间有相互的转移,其他用地的转化最为突出;总体而言,城市化、产业结构调整政策的引导以及人类活动等方面的因素共同推动了西海岸新区土地利用状况的变化. 相似文献
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1 INTRODUCTION Equations of state (EOS), especially, cubic equa-tions of state are frequently used in modeling phase equi-librium for chemical process of designing. Among cubic equations of state, SRK[1] equation of state and PR[2] equation of state are the most commonly used. These two equations of state are similar in form. They are also similar in the correction factor of parameter a. When phase equilibria of mixtures were calculated, equations of state must be combining with mixing… 相似文献
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Based on results of saturated vapor pressures of pure substances calculated by SRK equation of state,the factor α in attractive pressure term was modified. Vapor-liquid equilibria of mixtures were calculated by original and modified SRK equation of state combined with MHV1 mixing rule and UNIFAC model, respectively. For 1447 saturated pressure points of 37 substance including alkanes; organics containing chlorine, fluorine, and oxygen; inorganic gases and water, the original SRK equation of state predicted pressure with an average deviation of 2.521% and modified one 1.673%. Binary vapor-liquid equilibria of alcohols containing mixtures and water containing mixtures also indicated that the SRK equation of state with the modified α had a better precision than that with the original one. 相似文献
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依据酸性催化剂表面吸附态物种分子产生红外信号的机理,采用原位漫反射红外光谱技术对甲醇制烯烃反应中不同反应时间与床层位置的SAPO-34催化剂积炭行为进行研究。结果表明,反应时间与床层位置的变化对SAPO-34催化剂积炭数量和物种有显著影响。反应时间延长导致SAPO-34催化剂积炭量增加,且积炭成分中重组分稠环芳烃比例上升,积炭速率逐渐加快。积炭量随床层位置自上而下逐渐减少,失活催化剂笼中烷基芳香烃类积炭通过环化和脱氢逐渐转变为多环芳香烃类。 相似文献
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Mathematica软件在化工热力学教学中的应用 总被引:1,自引:0,他引:1
化工热力学以公式多,计算复杂成为化工专业难教难学的课程之一。本文介绍Mathematica在状态方程参数确定、体积根的求解、相平衡计算等教学过程中的应用。该软件可使复杂、抽象的化工热力学计算过程具体化,将传统教学中不适合课堂教学的内容引入课堂中。利用Mathematica进行化工热力学教学可成为Power Point等多媒体教学的一种补充方式。 相似文献
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在M催化剂组分中引入甲基环己基二甲氧基硅烷作为给电子体制备了新型高活性气相聚乙烯GM催化剂,通过BET和SEM等方法对GM催化剂进行了表征;采用淤浆聚合的方法评价了GM催化剂的活性,考察了GM催化剂的动力学行为,并在Unipol工艺气相聚乙烯装置上进行了工业试验。试验结果表明,在冷凝态操作模式下GM催化剂的活性达5000~6000g/g,聚乙烯产品的堆密度达0.40g/cm~3,比M催化剂的活性提高近一倍,聚乙烯产品的堆密度提高近25%。GM催化剂的氢调敏感性优于M催化剂,共聚性能与M催化剂相当。工业试验过程中装置运行稳定,各项操作参数均能满足工艺要求,得到的聚乙烯产品为优级品。 相似文献
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对华北油田钻井废水的13项污染物特征进行了分析,结果表明:Cd、Ni、Cr6+ 、Cu、Mn、COD、色度和pH值不同程度超出GB 8978─1996《污水综合排放标准》的限值要求,污染样品占总样品的比例分别为17.34%,3.47%,5.20%,5.20%,13.87%,34.10%,54.34%和18.50%;Cd、COD、色度和pH值是主要污染因子,在钻井废水的管理和无害化处理中要尤其关注。5个采油分厂都存在Cd、Mn、色度和pH值的污染情况; 采油四厂钻井废水的污染项目最多,污染率高。相关性分析结果表明:污水的污染程度随井深呈加重趋势;各污染因子中,Ni、Cr、Cr6+、Cu、Mn、色度和COD具有同源性;废水的色度主要由水中溶解的金属组分引起,有机污染物也是导致色度高的重要因素。 相似文献
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Based on results of saturated vapor pressures of pure substances calculated by SRK equation of state, the factor a in attractive pressure term was modified. Vapor-liquid equilibria of mixtures were calculated by original and modified SRK equation of state combined with MHV1 mixing rule and UNIFAC model, respectively. For 1447 saturated pressure points of 37 substance including alkanes; organics containing chlorine, fluorine, and oxygen; inorganic gases and water, the original SRK equation of state predicted pressure with an average deviation of 2.521% and modified one 1.673%. Binary vapor-liquid equilibria of alcohols containing mixtures and water containing mixtures also indicated that the SRK equation of state with the modified a had a better precision than that with the original one. 相似文献