nitrogen-free meaning in English
无氮的
Examples
- In nitrogen - free medium , the logarithmic phase of the strain w12 was about 13 - 48 h . in logarithmic period its doubling time was 2 - 4 h in nitrogen - free medium , 0 . 9 - lh when enough nk
在无氮培养基上该菌在13h后进入对数生长期，并持续至48 52h ，这期间其生长代时为2 - 4h ，有氮培养基上为0 . 9 - 1h 。 - For analytical weighing . smooth surface is ideal for transferring weighed material . clean , dust - free sheets . paper is lightweight , yet strong enough to support analytical size samples . nitrogen - free
可用于分析装配能够称量，极光滑的表面易于转移称量物品，称量纸洁净的无尘，质地很轻，但有足够的强度可以拿起所称量的物品。 - Effects of diverse environmental factors on the growth rate ( od4oo ) and nitrogenase activity ( ara ) of the strain w12 hi nitrogen - free culture were investigated in our experiments . the results implied that the strain w12 could easily adapt to different cultural conditions : it could use various carbon sources ( especially glucose , sucrose , malic acid , mannitol ) , propagate quickly and fix nitrogen at a temperature range of 15 ? to 40 ? and at 25 - 35 ? for optimum , at a ph range of 4 to 8 . 5 , at a saline concentration range of 0 . 01 % to 1 . 5 % ; low nlv " concentration had little effect on its nitrogenase activity . ara could also be detected when it grow in the culture media with 5mmol / l ntv "
W12菌株对环境因子的适应性研究：无氮培养条件下，测定温度、碳源、酸碱度、渗透压对w12生长及固氮能力的影响，结果表明，在15 - 40下均能生长并表达固氮酶活性，其最适生长及固氮的温度为25 - 35 ；能利用葡萄糖、蔗糖、苹果酸、甘露醇等多种碳源生长并固氮，当培养基中同时存在蔗糖和苹果酸时，细菌生长和固氮活性最强；在偏酸和偏碱的条件下( ph4 . 5 - 8 . 5 )均能保持较强的生长势和较高的固氮酶活性，并能通过调节自身代谢平衡并适应环境的酸、碱性变化，使培养液趋于中性：能耐受较高的渗透压，培养液中卜、 5 naci浓度对其生长和固氮酶活性影响不大，当naci浓度升至2时，菌株的生长势及固氮酶活性才有所下降：低浓度的铰对其固氮酶活性影响不大，在0 - In this study , 5 rhizosphere soil samples of wheat , maize , ryegrasses and willow tree were collected from campus of china agricultural university and beijing chaoyangqu , respectively . a total of 29 isolates were selectively obtained from these rhizosphere soli samples based on their growth on nitrogen - free medium and their resistance to 100 for 10 - 15 min
本文在中国农业大学科学园区采集了小麦和玉米的根际土，从北京市朝阳区洼里分别选择不同环境采集2个黑麦草根际土壤样品和1个柳树根部的土壤样品，分别从这5个土壤样品中分离固氮的芽孢杆菌。