| 1. | Pay special attention to the sign of the answer .
特别注意答案的正负号。 |
| 2. | The positive and negative ions become separated or dissociated .
正负离子彼此分开或解离。 |
| 3. | It is now necessary to introduce a sign convention for radii of curvature .
现在必须介绍曲率半径的正负号规则。 |
| 4. | A molecule where the centers do not coincide is called a polar molecule .
正负电荷中心不重合的分子称为极性分子。 |
| 5. | The chipped area is not between the lugs of adjacent positive and negative plates .
破碎部分不在相邻的正负极耳之间。 |
| 6. | When any two rows or two columns are interchanged, the sign of the determinant is changed .
当任何两行或两列互换时，行列式的正负号改变。 |
| 7. | He did not use negative numbers, which he regarded as contradictory, but introduced a complicated scheme called "correspondence of signs" .
他不使用他认为有矛盾的负数，却引进了一套复杂的图表，称为“正负号的对应”。 |
| 8. | In an aerosol containing equal numbers of charged particles of both signs, the diffusive encounters for oppositely charged particles are more effective than for uncharged particles .
若气溶胶中含有等量正负带电粒子，那么正负带电粒子间的扩散碰撞比非带电粒子更容易实现。 |
| 9. | Rise fall time , positive negative pulse width ,
上升下降时间,正负脉冲宽度, |
| 10. | Positive and negative forces ; move objects psychically
正负力量，隔空移物 |
