Mixed ensiling quality of maize straw with waste cabbage and biogas production potential analysis

Growing energy consumption and diminishing fossil fuel supplies have encouraged increased research on renewable energy sources and development of new energy production processes. Biogas production from agricultural biomass is of growing importance as it

玉米秸秆与废弃白菜的混合青贮品质及产沼气能力分析

为实现干玉米秸秆（dried maize straw,DMS）的长时间保质贮存,利用青贮原理将DMS与废弃白菜（cabbage waste,CW）连续混贮90 d,设置DMS单贮组和6个不同质量比例（DMS：CW=29：19、27：21、25：23、23：25、21：27和19：29）混贮组,间隔30 d分析其贮存品质,筛选适宜贮存条件,并考察秸秆贮存前后的微观结构变化和产沼气潜力。结果表明,与单贮组相比,6个混贮组的p H值均显著下降（P〈0.05）,乳酸含量显著升高（P〈0.05）,混贮品质优于单贮。6个混贮组贮存30 d时的p H值均为最低,乳酸含量最高,感官评价均为优级,30 d后p H值有所上升,乳酸含量急剧下降,60d时的木质素含量显著降低（P〈0.05）,综纤维素含量显著升高（P〈0.05）。随着CW比例增加,混贮组p H值逐渐减小,乳酸含量逐渐增加,MEⅤ组（DMS：CW=21：27）p H值最低,乳酸含量最高,能使DMS连续贮存60 d不变质。扫描电镜结果显示,青贮发酵使干秸秆原先致密复杂的木质纤维结构开始瓦解,青贮秸秆表面有很多裂缝和孔洞,与微生物或酶的可接触面积增加。沼气发酵试验表明,MEⅤ组混贮秸秆的累积产气量略高于未贮存干秸秆,且累积甲烷产量提高了61.67%,是未贮存干秸秆的1.6倍。Modified Gompertz模型显示混贮秸秆的甲烷生成速率增加,产甲烷能力提高。总之,当DMS∶CW质量比为21∶27（含水率为73%）时DMS能连续保质贮存2月,且贮存后秸秆的甲烷产量明显提升

Prediction of Energy Resolution in the JUNO Experiment

International audienceThis paper presents the energy resolution study in the JUNO experiment, incorporating the latest knowledge acquired during the detector construction phase. The determination of neutrino mass ordering in JUNO requires an exceptional energy resolution better than 3% at 1 MeV. To achieve this ambitious goal, significant efforts have been undertaken in the design and production of the key components of the JUNO detector. Various factors affecting the detection of inverse beta decay signals have an impact on the energy resolution, extending beyond the statistical fluctuations of the detected number of photons, such as the properties of liquid scintillator, performance of photomultiplier tubes, and the energy reconstruction algorithm. To account for these effects, a full JUNO simulation and reconstruction approach is employed. This enables the modeling of all relevant effects and the evaluation of associated inputs to accurately estimate the energy resolution. The study reveals an energy resolution of 2.95% at 1 MeV. Furthermore, the study assesses the contribution of major effects to the overall energy resolution budget. This analysis serves as a reference for interpreting future measurements of energy resolution during JUNO data taking. Moreover, it provides a guideline in comprehending the energy resolution characteristics of liquid scintillator-based detectors