以下关于膜技术特点及虚用的说法错误的是:?gggg#g?列关于流程描述正确的是:
A. 纳滤对Na+、Cl-的去除效率高于对Mg2+,Ca2+,S042-的去除效率
B. 反渗透可有效分离1nm以下的无机离子以及小分子
C. 超滤不具备脱盐性能,但可有效去除水中的细菌。病毒、大分子微粒
D. 微滤可分离水体中细菌、粘土微粒
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口底蜂窝织炎的表现为
A. 多有眶下区弥漫性水肿
B. 以下颌角为中心的咬肌区红肿伴明显张口受限
C. 先有牙痛史,继而出现张口受限
D. 多出现颌下三角区的红肿
E. 多出现颌下、口底广泛水肿
最早明确提出“以形写神”为中心的传神论的画家是()。
A. 吴道子
B. 张璨
C. 顾恺之
D. 谢赫
听力原文: Most rain forests lie close to the equator, where the climate is often mild and there are long hours of sunshine. The warmth of the land heats the air above, causing it to rise and tiny drops of water to fall as rain. The rainfall can reach at least 98 inches a year. This wet, warm world with plenty of sunlight is perfect for plants to grow, so the trees grow fast with green leaves all the year round. The trees themselves also have an effect on the climate. They gather water from the soil and pass it out into the air through their leaves. The wet air then forms clouds, which hang over the tree tops like smoke. These clouds protect the forest from the daytime heat and nighttime cold of nearby deserts, keeping temperatures fit for plant growth. Rain forests slightly farther away from the equator remain just as warm, but they have a dry season of three months or more when little rain falls. Tree leaves fall during this dry season and new leaves grow when the wet season or monsoon(rainy season)begins. Thus these areas are known as the "monsoon forest". Another type of rain forest grows on tropical mountains. It is often called the "cloud forest" because clouds often hang over the trees like fog. The rain forest is the ideal place for the growth of many different trees. Most of them depend on animals to eat their fruits and spread their seeds. When the fruits are eaten, the seeds inside them go undamaged through the animals stomachs and are passed out in their droppings. The seeds lying on the forest floor then grow into new trees. Questions 19 to 21 are based on the passage you have just heard. 19. What do we know about the climate of the rain forests near the equator? 20. What can we learn from the passage? 21. Which plays the most important role in the spreading of seeds according to the passage?20.
A. Tree leaves are green all the time in the monsoon forest.
B. There is a dry season in the cloud forest on tropical mountains.
Clouds help the plants in the rain forest near the deserts to grow.
D. The formation of climate in the rain forest has little to do with the trees.
______和______被公认为体系结构的两大类构成部分。