“environmental problems”的概念、定义、翻译、参考文献-科学参考

单词	environmental problems
释义	environmental problems Encyclopedia 工学〔基础词条〕释 environmental problems环境问题由于人类活动作用于周围环境所引起的环境质量和自然资源的变化，以及这种变化对人类的生产、生活和健康造成的影响。
随便看	positive quadratic form positive quantity positive ray function positive real axis positive real control positive real function positive real number positive real part positive real system positive recurrent point positive recurrent state positive reinforcement positive relation positive result positive root positive root system positive rotation positive school of criminology positive selection positive self-adjoint operator positive self-regard positive semi-definite positive semi-definite form positive semi definite Hermitian matrix positive semi-definite Hermitian matrix

科学参考收录了854744条科技类词条，基本涵盖了常见科技类参考文献及英语词汇的翻译，是科学学习和研究的有利工具。