Nitrogen and water are major factors for maintaining crop yield, getting better economic return.
氮素和水分是维持水稻高产和获得较高经济效益的主要因素。
An outdoor pot experiment was conducted to elucidate nitrogen dynamic characteristics in surface water of paddy soil with straw return with landfill.
采用盆栽试验方法研究了秸秆填埋对水稻土表层水三氮动态变化的影响。
It is equipped with asphalt return tube, anti-puffing pressure vent valve, anti-aging overhead nitrogen valve, thermometer, volumeter and output asphalt rapid discharge valve and coupling.
配备沥青溢流管、防冒液呼吸阀、防老化顶置充氮阀、温度计、容量计和输出沥青的快速卸料阀及接耦。
The effects of the return sludge ratio and the return mixed liquid ratio on the removal of nitrogen and phosphorus were studied in the modified A2/O process.
重点介绍了坂雪岗污水处理厂的复合改良A2/O工艺的运行方式及除磷效果，并分析了实际运行中存在的问题及工程设计时的注意事项。
The effects of the return sludge ratio and the return mixed liquid ratio on the removal of nitrogen and phosphorus were studied in the modified A2/O process.
重点介绍了坂雪岗污水处理厂的复合改良A2/O工艺的运行方式及除磷效果，并分析了实际运行中存在的问题及工程设计时的注意事项。
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