不同水氮供应对菜地土壤硝态氮累积的影响

通过田间小区和土柱模拟试验相结合的方法研究了不同水氮供应对菜地土壤硝态氮淋溶的影响，结果表明，在田间小区和土柱模拟试验中，硝态氮在1m土层内出现一个累积峰，并且随着灌水量的增加累积峰逐渐下移；在相同灌水量下，随着氮肥施用量增加两个试验1m土壤中硝态氮储量均增多。在田间小区试验中，当施氮量低于270kg/hm^2时，相同的施氮量下，150、250、350mm^3个水平灌水量下1m土体内硝态氮储量多少为250mm〉150mm〉350mm，当施氮量超过270k加m^2时，土体内硝态氮累积量随着灌水量的增加而减少。在土柱模拟试验中，在相同的施氮量下，1m土体硝态氮的储量随着灌水量的增加而增加。     

基于种养结合的畜禽养殖环境承载力研究*——以舒兰市为例

[目的]种养结合有利于促进农作物秸秆和畜禽粪便的资源化利用,进而减少农业面源污染,促进农业绿色发展,当前确定区域种养的匹配问题是发展种养结合的关键。[方法]文章根据农田氮养分平衡理论,基于农作物秸秆和畜禽粪便就地就近利用的原则,结合种植和养殖业年度统计数据,利用修正的氮养分平衡法估算舒兰市畜禽养殖环境承载力,并分析全市各乡镇的种养平衡状况。[结果]2015年舒兰市单位农用地面积的实际畜禽养殖量为17.3头/hm~2(猪当量),理论估算出的单位农用地面积畜禽养殖环境承载力为14.6头/hm~2(猪当量),实际畜禽养殖量已经超出畜禽养殖环境承载力的上限;在17个乡镇中,有8个乡镇的实际养殖量还没有达到畜禽环境承载力的上限;如果考虑到畜禽粪便加工成有机肥可销往外地的情况,当全市有20%的畜禽粪便加工成有机肥,就能实现全市的种养平衡。[结论]在将来县域发展种养结合过程中,通过发展有机肥产业是缓解实际畜禽养殖量超出畜禽养殖环境承载力上限的可行办法,同时,应加强各乡镇的种养匹配的量化估算,科学规划各乡镇种植与养殖结构使之实现种养平衡,减少因种养不匹配带来的环境承载力负荷过大的问题。研究结果为舒兰市养殖业的可持续发展提供科学指导,为"南畜北移"战略的实施提供参考依据,对推动县域农业绿色发展具有一定的启示意义。     

Nitrogen fixation during decomposition of sugarcane (Saccharum officinarum) is an important contribution to nutrient supply in traditional dryland agricultural systems of Hawai'i

Nitrogen (N) is unique among essential elements required for life, in that it must be fixed from the vast atmospheric reservoir before most organisms can use it. Prior to industrial nitrogen fixation, many agricultural systems were limited in their productivity by N. What sustained N in the ancient Hawaiian dryland (rain-fed) agricultural systems that lacked legumes or other known significant N inputs? N-fixation during sugarcane (Saccharum officinarum) growth and litter decomposition was examined in settings representing pre-European Hawaiian agriculture. We did not detect associative N-fixation during the growth of five Hawaiian sugarcane cultivars. In contrast, N-fixation during the decomposition of leaf and stalk material was important. We found that the depth of the mulch layer significantly affected N-fixation levels during decomposition; values of N-fixation in different depths of senesced leaf litter ranged from 0.69 to 1.36?gN/kg of litter integrated over the lifetime of decomposition. Compared to senesced leaf litter, N-fixation during decomposition of non-senesced leaf litter was ～77% and stalk material ～140% per unit mass. Peak rates of N fixation occurred between 200 and 400 days of decomposition, and ranged from 1.37 to 3.27?gN/kg/yr. Our empirical results were extrapolated to represent the traditional Hawaiian cropping system; we calculated N-fixation inputs of 4.8–39.0 kgN/ha/yr, with fixed N adding 17–40% of the amount of N added through litter. Findings indicate that significant N may be introduced into natural cropping systems through mulching practices and that small changes in practices greatly alter the total inputs. The use of mulch was likely an important source of N in pre-industrial settings and may be used in contemporary systems to reduce nitrogen fertilizer requirements.     

影响己内酰胺废水处理效果的因素及控制措施

通过对己内酰胺生产废水治理操作中出现的问题进行分析,总结出影响延时序批式生物氧化硝化反应器(ENSBR)对该种废水处理效果的主要因素是pH值、氨氮污泥负荷、水质突变等,并提出及时监测水质、掌握运行状态、正确调整操作等控制措施。     

Three-Stage Combustion of Solid Fuel: Practical Experience of Boiler Updating

The experience of design and realization of three-stage combustion of solid fuel in the furnaces of acting boilers with a steam rate of 200 tons/h by different methods with allowance for the special features of the furnace burners is described. The efficiency of suppression of nitrogen oxides under forced deviations from the optimum conditions of organization of the process (due to the design, assembly, or financial limitations of the updating) is investigated. The emission of nitrogen oxides is decreased by 40 – 50% without using auxiliary fuel for obtaining a reduction medium.     

窑泥沟人工湿地应用研究及新构思

以云南省澄江县污染最为严重的窑泥沟为研究对象,从植物、填料和工艺流程等方面,分析和研究了复合型人工湿地对污染物的去除情况,尤其是在不同季节进水浓度变化较大时氮磷的去除情况,并由此找出了存在的一些问题,提出了解决的构思。     

Technical solutions for a modernized TPE-216M boiler in a highly efficient unit

A design is presented for a modernized lignite-fired TPE-216M boiler for a highly efficient 225-MW power-generating unit, which can be installed at the Kharanorskaya state area power plant (Station No. 3). The boiler has a guaranteed gross efficiency of 92.5%, and satisfies modern ecological requirements: NO_x concentration of less then 300 mg/m³ in the flue gases, owing to the high gross efficiency of the unit, which is no less than 40%, NO_x emissions computed per 1 kW · h are reduced additionally by 10%, and the same applies to CO₂ emissions. The temperature of the steam is raised from 545 to 565°C. A low-pressure water economizer, which is included in the heat diagram of the unit, is installed to lower the temperature of the exiting gases. __________ Translated from élektricheskie Stantsii, No. 6, pp. 8–13, June, 2006.     

氧化沟的脱氮除磷工艺应用评述

介绍了国内典型的A2/C氧化沟、奥贝尔氧化沟和DE氧化沟的工作原理及其特点,总结各自的结构及工艺对脱氮除磷效果的影响。最后指出,生物除磷脱氮技术的发展和提高氧化沟中微生物活性是氧化沟未来发展的重要推动力;今后要进一步提高研究氧化沟设备性能和监控技术,减少占地面积和工程造价。     

IGCC系统低NOx排放方法的比较和分析

氮气回注、燃料湿化饱和是整体煤气化联合循环系统（IGCC）中降低燃机NOx排放的2种重要方法，针对200MW级IGCC系统设计，对IGCC系统中2种低氮燃烧方式进行计算和分析，从技术指标和经济性的角度阐述了2种方案的优缺点，并给出合理化建议。     

从废旧锌锰电池中回收汞和铵的工艺研究

针对废旧锌锰电池中汞分散存在,给回收处理废旧锌锰电池工作完全回收汞所带来的麻烦,本研究利用汞和铵的性质特点,找到了从废旧锌锰电池中集中回收汞和铵的工艺条件,为废旧锌锰电池的资源化,防止二次污染创造了有利条件.