什么是低位放顶煤液压支架？低位放顶煤液压支架的结构特点有哪些？
参考答案：
放煤口设在掩护梁下部，使用两部运输机，其后部输送机直接放在底板上火支架底座后方的托板上，通过放煤板进行放煤的支架称低位放顶煤液压支架，又叫插板式放顶煤液压支架。
结构特点：
（1）架型为支撑掩护式双输送机放顶煤液压支架，四连杆机构布置在前后排立柱之间，可承受顶板的水平分力。
（2）顶梁前端铰接前梁，其上有外伸式缩梁；顶梁上有一个100X120mm、倾角为65°的窗口，平时封闭，可用于煤不易冒落时进行打眼，人工强制房顶或注水处理火情，顶梁下部设有喷水装置。
（3）掩护梁又称尾梁，只与顶梁后部铰接，不与底座相连；它受尾梁千斤顶控制，可以上下摆动30°角，以松动顶煤；其下部有液压控制的伸缩式放顶煤插板，可控制煤的排放和大块煤的破碎。
（4）底座为整体刚性底座，后部铰接有托板，用以铺设后部输送机，以适应底板的起伏。
（5）顶梁和掩护梁都设有侧护板，用于架间密封盒调架。
| The first and most important agents of socialization are the people who care for infants. In the earliest months, messages from nurturers constitute the child’s basic understanding of the world around it. This is the infant’s first introduction to the language that shapes perception and elicits emotion. Another powerful source of information and socialization is the friendship of peers. Peers are equals that one can deal with on the same level as oneself, whereas parents are superiors. The heavy emotional overlay of family relationships makes some kinds of learning difficult. Much formal socialization is placed in the hands of professionals. Teachers from kindergarten on are specifically designated agents of socialization. Ideally, a teacher is one who has both knowledge and the skills to present it. During the course of teaching their subjects, classroom instructors provide role models and attempt to convey the excitement of learning itself. In earlier times, parents, friends and teachers would comprise the list of primary childhood socializers. Children’s books, comics and magazines might also have been mentioned as sources of information on norms and role models. Today one must add three powerful indirect or nonpersonal socialization agents: radio, movies and television. Many people learn about politics, form a vision of well-being, and develop attitudes towards others from what they see on the screen and hear through the speakers. |
Which of the following statements is NOT true
A．Language shapes an infant’s perception.
B．Language elicits an infant’s emotions.
C．Language forms an infant’s cultural awareness.
D．Language forms an infant’s basic understanding.