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水稻根系生长对不同氮形态响应的动态变化

土壤 2007年第5期39卷 766-771页

作者：赵学强施卫明土壤与农业可持续发展国家重点实验室(中国科学院南京土壤研究所) 中国科学院研究生院北京100049

土壤养分供应变异很大,植物根系生长对这种养分变异的响应非常敏感。为了探索水稻根系生长对N素供应响应的动态变化规律以及这种适应性变化与水稻N效率之间的关系,采用水培方法,以两个苗期不同N效率水稻品种桂单4号和南光为研究材料,比... 详细信息

土壤养分供应变异很大,植物根系生长对这种养分变异的响应非常敏感。为了探索水稻根系生长对N素供应响应的动态变化规律以及这种适应性变化与水稻N效率之间的关系,采用水培方法,以两个苗期不同N效率水稻品种桂单4号和南光为研究材料,比较了不同铵硝比、不同浓度NH_4^+、不同浓度NO_3^-和不同浓度NH_4NO_3对水稻根系构型参数的影响。结果表明:NH_4^+和NH_4NO_3供应显著降低了总根长、总根表面积和总根体积,且有增加平均根直径的趋势;而no3-供应在0~1mmol/L浓度范围内,增加了总根长、总根表面积和总根体积,降低了平均根直径,但当NO_3^-供应超过1mmol/L后,NO_3^-却有降低总根长、总根表面积和总根体积的趋势,对平均根直径没有明显影响。苗期N高效基因型桂单4号总根长和总根表面积在各种N素营养条件下均显著高于N低效基因型南光。上述结果表明,NH_4^+和NH_4NO_3都抑制了水稻根系生长,而NO_3^-为低浓度诱导、高浓度抑制根系生长,根长和根表面积,对提高水稻N效率贡献较大。

关键词： NH4+ no3- 根系水稻基因型

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NO_3^-光催化脱色染料废水的研究

工业水处理 2011年第2期31卷 58-60页

作者：李建章冯发美钟俊波曾俊四川理工学院化学与制药工程学院绿色催化四川省高校重点实验室四川自贡643000

染料工业废水在排放前必须加以处理。光催化在染料废水处理方面显示了巨大的应用优势。研究试验在no3-存在下用紫外灯照射对甲基橙溶液进行光催化脱色。结果表明:随着no3-含量的逐渐增加,甲基橙脱色率逐渐增加,在实验范围内没有出现no3... 详细信息

染料工业废水在排放前必须加以处理。光催化在染料废水处理方面显示了巨大的应用优势。研究试验在no3-存在下用紫外灯照射对甲基橙溶液进行光催化脱色。结果表明:随着no3-含量的逐渐增加,甲基橙脱色率逐渐增加,在实验范围内没有出现no3-加入量的最佳值;甲基橙在酸性条件下的脱色率高于碱性条件下的脱色率;当甲基橙质量浓度≤25mg/L时,光催化脱色反应为准一级反应;利用含no3-废水在日光下对实际染料废水的脱色效果好,可以达到以废治废的目的。

关键词： no3- 光催化脱色甲基橙染料废水

离子色谱法测定腊肠中NO_2^-和NO_3^-含量

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食品科学 2010年第6期31卷 213-215页

作者：冯顺卿李明珠劳锦花中山大学水产品安全教育部重点实验室中山大学测试中心广东广州510275 中山大学生命科学学院生物化学系广东广州510275 中山大学药学院广东广州510006

研究腊肠中的NO2-和no3-的离子色谱-电导检测测定方法。样品用超纯水超声波辅助提取,除去脂肪、蛋白质和大量的Cl-干扰后,用离子色谱进行测定。采用IonPac AS9-HC(4mm×250mm)分析柱以及相应的保护柱IonPac AG9-HC(4mm×50mm),以9.0mmol... 详细信息

研究腊肠中的NO2-和no3-的离子色谱-电导检测测定方法。样品用超纯水超声波辅助提取,除去脂肪、蛋白质和大量的Cl-干扰后,用离子色谱进行测定。采用IonPac AS9-HC(4mm×250mm)分析柱以及相应的保护柱IonPac AG9-HC(4mm×50mm),以9.0mmol/LNa2CO3溶液为淋洗液。NO2-和no3-的质量浓度与其峰面积具有很好的线性和重复性,其检出限分别为0.5、1.0mg/kg。

关键词：离子色谱腊肠 NO2- no3-

大气PM_(2.5)在线监测仪对SO_4^(2-)、NO_3^-和NH_4^+的测定评价

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环境化学 2012年第11期31卷 1808-1815页

作者：袁超王韬高晓梅聂玮雷国强徐政王文兴山东大学环境研究院济南250100 香港理工大学土木及环境工程系香港特区政府环境保护署

通过两套大气细颗粒物(PM2.5)水溶性离子在线监测仪与蜂巢式固气分离器膜采样系统作对比,评估了在线监测仪器对主要水溶性组分SO24-、no3-和NH4+的测定结果.美国URG公司生产的在线连续监测分析系统(AIM URG-9000B)对NH4+和no3-的监测结... 详细信息

通过两套大气细颗粒物(PM2.5)水溶性离子在线监测仪与蜂巢式固气分离器膜采样系统作对比,评估了在线监测仪器对主要水溶性组分SO24-、no3-和NH4+的测定结果.美国URG公司生产的在线连续监测分析系统(AIM URG-9000B)对NH4+和no3-的监测结果较好,但对SO24-的测定结果存在明显高估,其原因是AIM的平板溶蚀器系统无法完全去除大气中高浓度SO2,从而对SO24-的测定结果有干扰.为解决这一问题,进行了一系列实验,结果表明采用两个溶蚀器串联并用5 mmol.L-1H2O2+5 mmol.L-1NaOH混合溶液作吸收液时,高浓度的SO2(甚至达到260μg.m-3)可以被完全吸收而对SO24-的测定结果不产生影响.由荷兰能源研究所(ECN)、Metrohm和Applikon共同研制的在线气体组分及气溶胶监测系统(MARGA,ADI2080)对NH4+和SO24-的监测结果较好,可以满足实验要求;但no3-的测定结果偏高,其准确性需作进一步评估.新型监测仪器在不同大气环境中投入使用前需进行对比测试,以确定其准确性和精确性.

关键词： PM25在线监测系统 AIM MARGA NH4+ no3- SO24-

Atmospheric wet and dry deposition of dissolved inorganic nitrogen to the South China Sea

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Science China Earth Sciences 2020年第9期63卷 1339-1352页

作者： Ying GAO Lifang WANG Xianghui GUO Yi XU Li LUO State Key Laboratory of Marine Environmental Science Xiamen UniversityXiamen 361102China College of Ocean and Earth Sciences Xiamen UniversityXiamen 361102China Fujian Provincial Key Laboratory for Coastal Ecology and Environmental Studies Xiamen UniversityXiamen 361102China Jiangxi Provincial Key Laboratory for Causes and Control of Atmospheric Pollution East China University of TechnologyNanchang 330013China

At the global scale,atmospheric inputs of nitrogen are an important source of the new nitrogen that supports new marine production,especially in oligotrophic open oceans and marginal *** study reports quantities of atmospheric deposition of dissolved inorganic nitrogen(DIN)to the largest marginal sea in the North Pacific(the oligotrophic South China Sea,SCS)based primarily on rainwater sampling in the open northwestern region(Yongxing Island)from 2013 to 2015,and aerosol sampling from the SCS basin in June *** wet and dry deposition of DIN and their potential contributions to productivity were *** volume-weighted mean rainwater concentrations during the wet and dry seasons were 4.9 and 18.1μmol L-1 for N+N(no3-+NO2-),and 5.7 and 4.0μmol L-1 for NH4+,*** concentrations of DIN were lower in the marginal seas than in the open *** aerosol no3-concentration was 1.15±1.18μg m-3 during the wet season,which is slightly lower than reported for the East China Sea and East Sea,but higher than in the Arabian *** wet and dry deposition rates ranged from 0.4-3.9 and 0.4-1.2 mmol m-2 mon-1 for no3-,and 0.2-1.3 and 0.01-0.02 mmol m-2 mon-1 for NH4+,*** annual wet and dry deposition fluxes of DIN were estimated to be 16.8 and 10.1 mmol m-2yr-1,*** to other marginal seas,the SCS receives less atmospheric no3-inputs than the Yellow Sea,East China Sea,East Sea,and northeastern Mediterranean *** total atmospheric DIN deposition may account for 1.8-11.1%of the nitrogen supporting new production and 0.7-1.8%of the nitrogen supporting primary production.

关键词： South China Sea Atmospheric deposition Wet deposition Dry deposition Nitrate no3- Ammonium NH4+

离子色谱法测定有机肥中Cl^-、NO_3^-、SO_4^(2-)、PO_4^(3-)的含量

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分析试验室 2011年第9期30卷 79-81页

作者：吴玉萍夏振远雷丽萍沐雪云南省烟草农业科学研究院玉溪653100

研究了用离子色谱法同时测定有机肥中Cl-、no3-、SO42-、PO43-的含量。对样品前处理的条件进行优化,Cl-、no3-、SO42-、PO43-各成分的检出限分别为0.01、0.05、0.05、0.05 mg/L;平均回收率分别为102.4%、99.1%、106.8%、103.5%。对11个... 详细信息

研究了用离子色谱法同时测定有机肥中Cl-、no3-、SO42-、PO43-的含量。对样品前处理的条件进行优化,Cl-、no3-、SO42-、PO43-各成分的检出限分别为0.01、0.05、0.05、0.05 mg/L;平均回收率分别为102.4%、99.1%、106.8%、103.5%。对11个实际样品测定的相对标准偏差均在0.01%～9.7%之间;平均相对标准偏差Cl-为2.9%,no3-为2.6%,SO42-为4.8%,PO43-为3.2%。

关键词：离子色谱法 Cl- no3- SO42- PO43- 有机肥

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几种试剂对硝酸根光催化脱色甲基橙的影响

环境工程学报 2009年第5期3卷 854-856页

作者：李建章冯发美蒋维东曾俊黄生田四川理工学院化学系催化研究所自贡643000

以no3-为光催化剂,在紫外灯照射下,对甲基橙溶液进行光催化脱色。结果表明,叔丁醇、甲醇和乙醇对催化脱色反应有抑制作用;KB r和Na2SO4对脱色反应均有促进作用;而且KB r的加入量存在最佳值;Na2SO4的促进作用随Na2SO4的量的增加逐渐增强... 详细信息

以no3-为光催化剂,在紫外灯照射下,对甲基橙溶液进行光催化脱色。结果表明,叔丁醇、甲醇和乙醇对催化脱色反应有抑制作用;KB r和Na2SO4对脱色反应均有促进作用;而且KB r的加入量存在最佳值;Na2SO4的促进作用随Na2SO4的量的增加逐渐增强。Na2CO3的存在对甲基橙的脱色反应没有影响。K2S2O8和no3-之间存在较强的协同作用;K IO3和no3-之间存在相加作用;KB rO3和no3-之间存在拮抗作用。

关键词： no3- 光催化脱色甲基橙染料废水试剂

Dynamic Regulation of Nitrogen and Organic Acid Metabolism of Cherry Tomato Fruit as Affected by Different Nitrogen Forms

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Pedosphere 2012年第1期22卷 67-78页

作者： XU Xin-Juan LI Qing-Yu SONG Xiao-Huid Shen Qi-Rong Dong Cai-Xia College of Resources and Environmental Sciences Nanjing Agricultural UniversityNanjing 210095(China) Henan Institute of Science and Technology Xinxiang 453003(China) State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of SciencesNanjing 210008(China)

Cherry tomatoes （Lycopersicon esculentura Mill., cv. hongyangli） were hydroponically cultivated in a greenhouse to determine the effect of different nitrogen （N） forms on organic acid concentration and the activities of related enzymes involved in nitrogen and organic acid metabolism during cherry tomato fruit development. The results showed that fruit nitrate reductase （NR） activity was much higher following treatment with 100% no3 and 75% no3 ＋ 25% NH＋ than with 100% NH＋ except at maturity. Glutamine synthetase （GS） activity trended downward during fruit development under all three treatments. Plants fed 100% NH＋ had the lowest fruit citrate and malate levels at maturity, with the highest malate concentration at an early stage. The activity of phosphoenolpyruvate carboxylase （PEPC） was found to be in accord with the malate concentration with every N source. Under all three N forms, the citrate synthase （CS） activity peaked one week before the citrate concentration.

关键词： citrate malate NH4+ no3- phosphoenolpyruvate carboxylase

Effects of Nitrate on the Growth of Lateral Root and Nitrogen Absorption in Rice

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Acta Botanica Sinica 2002年第6期44卷 678-683页

作者：王小兵吴平胡彬陈青爽浙江大学生命科学院杭州310029

Lateral root is primary organ for plant to explore and utilize soil nutrient efficiently. The development of lateral roots (LR) is controlled by both genetic factors and nutrient status in environment. To investigate the effects of nitrate (no3-) on rice lateral root growth and nitrogen (N) uptake efficiency under upland condition, three treatments, including root-split culture and whole plant culture in N sufficient and deficient conditions, were used in a vermiculite culture experiment. Root-split treatment showed that the growth of lateral roots was stimulated by localized nitrate supply. However, in whole plant culture, elongation of lateral roots was induced by no3- deficiency. The effects of no3- on rice lateral root growth were genotype-dependent. Similar N concentration, soluble sugar concentration and N content in shoot were observed in both root-split treatment and whole plant culture under no3- sufficient condition, suggesting that the nitrogen requirement for rice normal growth could be satisfied with only half of roots supplied with no3-. In the root-split treatment, N uptake was positively correlated with the average of lateral root length (ALRL) in no3--supplied side, suggesting that the ALRL is important for rice root N uptake in the environment where the nitrogen nutrient is limiting factor. No significant correlation was observed between N uptake and ALRL in whole plant culture under N sufficient condition, which implies that the length of lateral roots may not be the main factor to determine tire rice root N uptake in nutrient-rich zone. Morphological and metabolic evidence in this study provided some prospects for genetic improvement of root system characters to improve the efficiency of nutrient absorption in rice.

关键词： no3- lateral root growth nitrogen absorption root-split treatment rice