Study on the Relationships between Utilization Ratios and Conversion Rates of Nitrogen,Phosphorus and Potassium for Maize

This paper studied the relationships between utilization ratios and conversion rates of nitrogen,phosphorus and potassium for maize by data mining method based on data of"3414 fertilizer field trials"of maize by published papers from national soil testing and recommendation since 2005.The results and conclusions were as follows:①the conceptual model of fertilizer utilization ratio of maize for plot was that,Y N≈a+b×optimum yield,Y P≈a+b×optimum yield-c×optimum nitrogen application amount-d×optimum potassium application amount,Y K≈a-b×optimum nitrogen application amount-c×temperature in growth season-d×rainfall in growth season,respectively.②Fertilizer utilization ratio and nutrient conversion rate had 4 kinds of relationships.No significant relationships:22,of which 16 were soil nutrients and 5 were environmental factors,the results showed that soil nutrients and environmental factors had little effect on nutrient conversion rate and fertilizer utilization ratio;consistent significant relationships:14,illustrating that conversion rate and utilization ratio of maize were consistent in most cases,and it was because that maize was planted for a long term,and its fertilizer absorption law was basically stable;contrary significant relationships:0,illustrating that there was no reverse relationship between conversion rate and utilization ratio of maize;complementary significant relationships:18,the cause of the complementary phenomenon was that the fertilizer utilization ratio was the measuring index of fertilizer efficiency in one season,while the nutrient conversion rate was the measuring index of fertilizer efficiency in more seasons.It showed that the fertilizer utilization ratio was significantly correlated,or the nutrient conversion rate was significantly correlated.

Study on the Relationships between Utilization Ratios and Conversion Rates of Nitrogen,Phosphorus and Potassium for Wheat

This paper studied the relationships between utilization ratios and conversion rates of nitrogen,phosphorus and potassium for wheat by data mining method based on data of"3414 fertilizer field trials"of wheat by published papers from national soil testing and recommendation since 2005.The results and conclusions were as follows:①the conceptual model of fertilizer utilization ratio of wheat for plot was that,Y N≈a+b×optimum nitrogen application amount+c×optimum fertilizer amount of K+d×rainfall in growth season,Y P≈a+b×optimum fertilizer amount of K+c×rainfall in growth season,Y K≈a+b×temperature in growth season+c×rainfall in growth season-d×optimum yield-e×optimum nitrogen application amount,respectively.②Fertilizer utilization ratio and nutrient conversion rate had 4 kinds of relationships.No significant relationships:13,of which 8 were soil nutrients,the results showed that soil nutrients had little effect on nutrient conversion rate and fertilizer utilization ratio;consistent significant relationships:4,they were all nitrogen and phosphorus,explaining the importance of nitrogen and phosphorus;contrary significant relationships:6,they were all nitrogen and phosphorus,illustrating that phosphorus and nitrogen had inhibitory effect;complementary significant relationships:31,the cause of the complementary phenomenon was that the fertilizer utilization ratio was the measuring index of fertilizer efficiency in one season,while the nutrient conversion rate was the measuring index of fertilizer efficiency in more seasons.It showed that the fertilizer utilization rate was significantly correlated,or the nutrient conversion rate was significantly correlated.

Study on the Relationship between Utilization Ratios and Conversion Rates of Nitrogen,Phosphorus and Potassium for Rice

This paper studied the relationships between utilization ratios and conversion rates of nitrogen,phosphorus and potassium for rice by data mining method based on data of"3414 fertilizer field trials"of rice by published papers from national soil testing and recommendation since 2005.The results and conclusions were as follows:①the conceptual model of fertilizer utilization ratio of rice for plot was that,Y N≈a+b×optimum yield+c×optimum fertilizer amount of K,Y P≈a+b×optimum yield,Y K≈a respectively.②Fertilizer utilization ratio and nutrient conversion rate had 4 kinds of relationships:①no significant relationships:25,of which 14 were soil nutrients and 9 were environmental factors,the results showed that soil nutrients and environmental factors had little effect on nutrient yield ratio and fertilizer utilization ratio;②consistent significant relationships:2,one was that yield ratio and utilization ratio of N were positively correlated with the optimum production,explaining the importance of N for production,the other was that yield ratio and utilization ratio of P had a significantly positive correlation with conversion rate and utilization ratio of N,illustrating that nitrogen and phosphorus had mutual promotion;③contrary significant relationships:5,these showed as negative correlations of fertilizer utilization ratio and positive correlation of nutrient conversion ratio;④complementary significant relationships:22,the cause of the complementary phenomenon was that the fertilizer utilization ratio was the index of fertilizer efficiency in one season,while the nutrient conversion rate was the index of fertilizer efficiency in more seasons,which showed that the fertilizer utilization rate was significantly correlated,or the nutrient conversion rate was significantly correlated.

热电池FeS_(2)-CoS_(2)复合正极材料利用率的影响因素

采用高能球磨和磁悬浮筛分法制备了不同粒径的FeS_(2)-CoS_(2)复合正极材料,并通过单体电池放电试验研究了LiB/LiCl-LiBr-KBr/FeS_(2)-CoS_(2)热电池中正极材料粒径、正负极质量比和放电温度对正极材料利用率的影响。结果表明:在450℃条件下,当FeS_(2)粒径为7.85~59.12μm时,正极材料利用率随FeS_(2)粒径的减小而增大;当FeS_(2)粒径为3.30~7.85μm时,正极材料利用率随FeS_(2)粒径的减小而减小。FeS_(2)(7.85μm)-CoS_(2)(8.06μm)复合正极单体电池的放电性能最佳,截止电压1.5 V时,其放电比容量为342.4 mA·h·g^(-1),正极材料利用率为48.8%。随着单体电池工作时间的延长,其放电比容量随正负极质量比的减小而增大,在正负极质量比为1.67时,450℃条件下的FeS_(2)-CoS_(2)复合正极单体电池的放电比容量高于400℃和500℃,截止电压1.5 V时,其放电比容量为389.2 mA·h·g-1,正极材料利用率高达55.5%。

特长跨海公路隧道竖井组协同风量与防排烟设计研究

青岛第二海底隧道首创性地在两管隧道排烟道上纵向间隔设置联络烟道,将南北线烟道联通,以提高通风效率。因此,亟须明确不同竖井组协同风量对联络烟道风量的影响规律,确定最佳的南北线风量配比和两线竖井风量配比。对比不同风量配比对联络烟道风速、利用率的影响,结果表明,南北线风量配比的变化对联络烟道风速的影响较小,但能一定程度上缓解南北两线隧道因两侧风量相同而相互抽吸导致的隧道中心位置风速过低的情况。两线的风量配比对联络烟道风速有较大影响,当两线竖井风量配比由5∶5逐渐变化到2∶8时,联络烟道中间排烟道平均风速由0.89 m/s提升到1.18 m/s,提升幅度约为32.58%,联络烟道利用率由41.18%提升到54.75%,推荐使用不均衡的两线竖井风量配比模式,两线竖井风量配比为2∶8时具有最高的联络烟道利用率。并采用缩尺寸模型试验,验证了该风量配比设计的合理性。

提高湖羊圈养空间利用率的建模方案优化设计

为提高湖羊圈养的空间利用率,采用分期分批连续方式安排交配,根据交配期、怀孕期、哺乳期、休整期、育肥期等5个阶段的期长、容量、流转倍率等参数值,建立各期羊栏需求数的计算模型。针对养殖场现有的羊栏规格,经试算搜索得到其羊只的最佳流转速度,由此编制具体的生产方案,使得年化出栏羊只数量达到最大。继而针对5项不确定因素,构建参数重新选定的计算公式,并在合理范围内,调整哺乳期和空怀期时长,得到多种备选方案,再通过分层次计算比较各方案的期望损失,确定最优方案。

磷肥有机替代、秸秆还田对棉花养分吸收和磷肥利用效率的影响

为探究磷肥有机替代、秸秆还田对棉花养分吸收、磷肥利用效率及棉花产量的影响,本研究基于国家灰漠土肥力与肥料效益监测站5年田间微区棉花连作定位试验,以7种施肥措施为样本,于2022年棉花成熟期开展棉田土壤田间调查研究。结果表明,磷肥有机替代和秸秆还田均能提升棉株氮磷钾养分吸收,各器官氮素平均含量在1.75~40.90 g·kg^(-1)之间,磷素平均含量在1.46~11.28 g·kg^(-1)之间,钾素平均含量在3.11~25.03 g·kg^(-1)之间。综合肥料投入和养分吸收,50%的磷肥有机替代和秸秆还田最能增强棉株吸氮能力和促进干物质积累,50%的磷肥有机替代对棉株吸磷能力最强且最有利于实现棉花节肥增钾的效果。棉株各器官N:P变化范围为1.20~12.01,磷肥有机替代和秸秆还田使茎、叶、蕾/铃/壳的N∶P明显降低,棉株生物量、籽棉产量随茎、叶、蕾/铃/壳N∶P的降低而增加,本试验棉花生长更倾向于受N、P共同限制。磷肥利用率随有机替代量的增加从12.54%提升到33.04%,土壤磷素盈余量随有机替代量的增加从28.20 kg·hm^(-2)降低到19.66 kg·hm^(-2)。研究表明,在北疆灰漠土棉区采用50%磷肥有机替代,即施磷(P2O5)60.0 kg·hm^(-2)和配施羊粪9 784.8 kg·hm^(-2),对棉花产量、生物量、养分吸收的综合效应最优,值得推广应用。

不同形态氮肥配比对西瓜生长发育及氮肥利用率的影响

为明确不同形态氮肥及配比对西瓜生产性能的影响,为西瓜栽培中氮肥选择提供依据。以陇抗9号为供材,在等氮水平(N200kg/hm^(2))下,设3种形态氮肥(酰胺态氮、硝态氮、铵态氮)和3种硝铵配比(70%硝态氮+30%铵态氮、50%硝态氮+50%铵态氮、30%硝态氮+70%铵态氮)处理,研究了不同施肥处理对西瓜干物质积累、产量、品质及氮素养分积累利用指标的影响。结果表明,单一氮肥种类对西瓜植株干物质积累、产量、氮素养分积累及利用的影响为硝态氮>酰胺态氮>铵态氮;70%硝态氮+30%铵态氮能够维持较好的果实品质,其西瓜产量、经济收益、氮肥利用率和偏生产力最高,与酰胺态氮相比,西瓜产量提高了15.24%、经济收入增加了6056元/hm^(2)、氮肥利用率提高了7.95个百分点、氮肥偏生产力增加了15.24%。综上所述,西瓜生产在施氮200 kg/hm^(2)水平下以70%硝态氮+30%铵态氮的比例投入为佳,适宜在实际生产中应用。

基于煤质特性的京唐高炉喷吹煤结构优化

为优化首钢京唐高炉喷吹煤结构和降低冶炼成本,对京唐高炉喷吹煤粉的煤质特性进行了分析,用煤焦置换比理论公式计算了单种煤的理论置换比,并计算了京唐高炉喷吹煤的煤粉利用率。认为,随着高炉煤比的提高,煤焦置换比逐步降低;通过对配煤结构及高炉操作参数进行优化,京唐三座高炉的煤粉利用率得到进一步提升。1号高炉煤粉利用率达到了97.64%,2号高炉达到了97.58%,3号高炉达到了98.14%,较2022年6月分别提高了3%左右。

基于里斯特操作线的新钢2500 m^(3)高炉燃料比的降低

为实现新钢10号高炉的节能降耗,采用绘制Rist操作线的方式,通过实际操作线与理想操作线的对比,计算出煤气利用率和热风温度对焦比的影响,从而指导生产。根据高炉冶炼强度与燃料比的对应关系,确定出最适冶炼强度,并通过逐步扩大风口面积,适当增加风量以达到燃料消耗的最低点;与此同时,逐步增加外围和中间区域的矿石环数,整体扩大焦炭角度,缩小矿石布料平台,并根据煤气分布情况适当扩大矿石批重,发展边缘和中心两股气流。通过优化送风制度和装料制度,高炉煤气利用率提高了1.55%。此外,更换了热风炉预热器以及使用热风炉无扰换炉技术,进一步提高并稳定了风温,热风温度由1184℃上升至1204℃,最终高炉燃料比降至502 kg/t,在同行业处于领先水平。

肥料用量和养分配比对蔬菜生长及土壤肥力的影响

选择深圳市郊区常年连作菜地,采用田间小区试验方法,设置对照、常规施肥、减量施肥10%、优化施肥(减量施肥50%,氮磷钾优化配比)等不同处理,研究不同肥料用量和养分配比条件下减施化肥对蔬菜生长及土壤肥力的影响。试验以叶菜为供试蔬菜,连续种植2茬。结果表明,与不施肥处理相比,施肥显著增加蔬菜产量和氮、磷、钾养分吸收量,肥料增产贡献率为32.3%~37.7%,且化肥减施与常规施肥处理之间肥料贡献率无显著差异。常规施肥模式下蔬菜氮、磷、钾养分利用率分别为13.98%、5.39%、31.95%,优化施肥相比常规施肥显著提高蔬菜磷肥和钾肥利用率1.87倍、26.3%。施肥对土壤pH、有机质含量无明显影响,常规施肥、减量施肥10%提高土壤碱解氮含量12.27%~27.83%、有效磷含量26.49%~44.24%、速效钾含量13.17%~35.30%。与常规施肥相比,优化施肥显著降低土壤有效磷含量19.96%~23.65%、速效钾含量22.29%~23.23%。各处理土壤综合肥力指数为1.34~1.43,均属于II级水平,连续2茬短期施肥管理对土壤肥力指数无显著影响。总体上,常年连作菜地系统优化施肥即化肥减施50%并优化氮磷钾养分投入比例,可在蔬菜产量不降低的情况下维持土壤肥力水平,降低土壤有效磷累积导致的面源污染风险。

邯钢1号高炉中心加焦布料制度应用实践

邯钢1号高炉因受制于原料条件采用中心加焦的布料制度,料制进行了三次大调整,这些调整在一定时期内均实现了对炉内气流进行调节,达到稳定炉况、提高产量和降低燃料比的目的。对三次料制调整过程产生的效果和存在的问题进行了分析,料制调整中应坚持以中心为主,兼顾边缘管理,在基准料制的基础上结合炉况实际进行微调,实现高产低耗的目的。

某高校教学楼空调系统运行能耗数据分析

本文以能效比EER为依据,基于某高校教学楼空调系统的监测平台的历史能耗数据,分析比对了两学年的空调系统运行情况,当教室同时使用率大于0.68,系统末端能耗对能效比产生较大影响。降低末端能耗的前提是满足教室实际耗冷量,通过极大似然估计法估算出不同教室单位面积每小时所需冷量范围,得出其分别在124.2~148.96 W/m^(2)、52.5~96.26 W/m^(2),为后期制定空调系统运行阶段的节能策略提供一定参考。

高寒地区土族特色低能耗建筑集成技术研究与示范项目节能效果分析

应用低能耗建筑技术对于降低建筑领域的能耗和减少碳排放具有显著效果,是实现“双碳”目标的重要途经之一。该研究以高寒地区土族特色的低能耗建筑集成技术研究与示范项目为研究对象,通过优化围护结构设计、采用可再生能源等节能措施,对项目的围护结构和供暖系统进行了性能测试与节能效果评估。利用PKPM-EEP能效评估软件进行计算分析,结果显示该项目的节能效果显著,相对节能率达到22.95%。表明项目采取的低能耗建筑技术措施行之有效,可为今后进一步推广适用于农村地区低能耗建筑技术体系提供参考和技术支撑。

停车需求预测方法研究

为了能结合实际预测研究区域停车需求,介绍了目前主要的停车需求预测方法及各自特点．在停车生成率模型基础上建立停车需求—供应预测模型,该模型考虑了价格因素、停车服务水平对停车需求量的影响,将停车场周转率、利用率引入模型中,从而可直接得出实际应建停车位数量,同时,将停车需求分为白天和夜间分别进行预测,最后给出了计算示例．

缺氧/好氧比对连续流半亚硝化稳定性的影响

为研究不同缺氧好氧比对半亚硝化稳定性的影响,采用连续流反应器,在常温(22~25℃),DO(0.3~0.5mg/L)和FA协同作用下实现了全亚硝化后,转变进水为AO除磷二级出水,并逐步向半亚硝化过渡.在此过程中考察了不同缺氧好氧比(0:1、1:1、2:1和3:1)对半亚硝化稳定性的影响.结果表明,缺氧好氧比为0:1时,很难维持低NH_4^+-N(40~70mg/L)亚硝化的稳定,缺氧好氧比为1:1、2:1、3:1时均能维持稳定的半亚硝化效果,相比之下缺氧好氧比为3:1时更加节能;在缺氧好氧比0:1,1:1,2:1,和3:1的过程中,氨利用速率分别提高了29.57%、44.27%、45.23%、49.63%.在整个过程中污泥沉降性能良好,SVI在65~130m L/g.

施氮量和底追比例对小麦氮素吸收利用及子粒产量和蛋白质含量的影响

在大田栽培条件下,运用15N示踪技术研究了不同施氮量和底追肥比例对小麦氮素利用和子粒产量及蛋白质含量的影响。结果表明,施用氮肥提高了小麦植株的氮素积累量、子粒产量、蛋白质含量和蛋白质产量。相同施氮量条件下增加追肥氮的比例,提高了氮肥农学利用率和吸收利用率,增加了植株地上部器官(子粒+营养器官)中追肥氮、土壤氮的积累量,提高了营养器官中氮素的转运量和开花后氮素的同化量,增加了子粒蛋白质含量。相同的氮素底追肥比例条件下,将240 kg/hm2施氮量降至168 kg/hm2的处理,氮肥农学利用率、氮肥吸收利用率、氮肥偏生产力提高,子粒中土壤氮的积累量增加,植株地上部器官中土壤氮的积累量亦增加,开花后氮素同化量提高,子粒蛋白质含量增加。各施氮处理间子粒产量无显著差异。在本试验条件下,施氮量为168 kg/hm2且全部于拔节期追施是兼顾产量、品质和效益的优化处理。

施氮量与基追比例对烟叶品质及氮肥利用率的影响

通过3 年的田间试验,研究了不同施氮量和基追比例对烟叶化学成分、感官质量及氮肥利用率等的影响.结果表明,降低施氮量增加了烟叶的总糖、还原糖含量和糖碱比,降低了总植物碱、总氮、钾含量及钾氯比,改善了烟叶感官质量;降低施氮量显著降低了氮素积累量、来自肥料和土壤的氮量,显著提高了氮肥利用率.相同施氮量,随追肥比例增加,2009和2012 年度烟叶的总糖、还原糖含量及糖碱比先增加后降低,总植物碱、总氮含量先降低后增加;2010 年烟叶总糖、还原糖含量及糖碱比降低,总植物碱和总氮含量提高.2009、2010 年度感官质量分别以追肥比例为70%和50%的处理最佳;2012年度高施氮量以追肥比例为70%处理最佳,低施氮量以50%处理最好.增加追肥比例显著提高了氮肥利用率.通过3 年研究发现,施氮量从90 kg/hm^2 降至45-60 kg/hm^2,追肥比例增至50%-70%可改善烟叶感官质量及提高氮肥利用率.

施氮量和底追比例对小麦氮素利用和土壤硝态氮含量的影响

利用^15N同位素示踪技术研究了不同的施氮量和底追比例对小麦氮素利用和土壤硝态氮的影响。结果表明：底追比例均为5：5，处理2（纯氮施用量为168kg／hm^2）与处理1（纯氮施用量为240kg／hm^2）比较，处理2成熟期植株中土壤氮素的积累量，肥料氮的利用率均高于处理1的，但处理2的土壤硝态氮含量低；籽粒产量、蛋白质含量、湿面筋含量和面团稳定时间处理间无显著差异。纯氮施用量均为168kg／hm^2，氮肥全部用于拔节期追施的处理3与处理2比较，处理3成熟期植株中土壤氮素的积累量，籽粒蛋白质含量、面团稳定时间和0～40cm土层土壤硝态氮的含量均高于处理2的；肥料氮的利用率和籽粒产量处理间无显著差异。成熟期不同处理0～60cm土层土壤硝态氮含量均低于播种前，在60～80cm土层形成累积峰并高于播种前，但80cm以下层次与播前相比无明显差异。

中国工业水污染治理状况分析:基于污染源普查数据

文章目标是利用污染源普查数据评估中国工业行业水污染治理状况。利用SPSS的比较均值以及探索分析工具,以主要污染物去除效率,废水处理设施运转情况及企业废水治理设施投资和运行状况为评估指标,分析中国工业行业的水污染治理状况。主要结论如下:污染物的去除效率在不同行业间差异显著;企业废水治理设施运转情况较差;民营企业废水治理负担相对较重;企业可能存在虚报污染治理信息情况。针对研究结论,提出如下政策建议:一是要提高重金属、石油类等特征污染物的监测精度;二是要尽快制定关于工业企业废水处理设施运行规范性文件,加强工业企业的废水治理运行过程的监督和管理;三是要重视对民营企业的环境管理工作。