null ①零，零的 ②无效的，无价值的 ③类光[的]†
null 零的；零
数据库 数据库管理系统及其实现技术 释文 null 空值
- cyanobacteria
- cyanobacteria bloom
- cyanobacterial toxins
- cyanobacterium
- cyano bonded phase
- cyano-bonded phase
- cyanocobalamin
- cyano complex of iron
- cyanoethylation
- cyanoethylene
- cyanogen
- cyanogen band
- cyanogen halide
- cyanogenic glycoside
- cyanogenic glycosides
- cyanogen line
- cyanogen poisoning
- cyanogen radical
- cyanohydrin
- cyanometer
- cyanomethylation
- cyanometric titration
- cyanometry
- cyanophycean starch
- cyanophycin