雪花的奥秘

• 来源期刊: 海外英语
• 年，卷（期）: 2007,（8）
• 页码范围: 81
• 页数: 1页
• 语种: 中文

摘要

THAT NO TWO SNOWFLAKES1 LOOK EXACTLY ALIKE IS FAIRLY COMMON KNOWLEDGE. LESS WELL-KNOWN IS THAT A SNOWFLAKE''''S SHAPE DEPENDS ON THE TEMPERATURE AT WHICH IT FORMS. WHEN THE MERCURY2 HOVERS BETWEEN3-1℃ AND -3℃, SNOWFLAKES CRYSTALLIZE4 AS PLATES AND DENDRITES5. AT ABOUT -5℃, NEEDLES6 AND HOLLOW COLUMNS APPEAR. AT STILL COLDER TEMPERATURES, THE FLAKE DESIGN TEMPERATURES, THE FLAKE DESIGN RETURNS TO DENDRITES AND PLATES. AND WHEN SNOWFLAKES START FORMING INTO COLUMNS AS AROUND -5℃ BUT THEN ENCOUNTER