Analysis of ingredient and heating value of municipal solid waste

Great differences between municipal solid wastes (MSW) produced at different places and different times in terms of such parameters as physical ingredient and heating value lead to difficulty in effective handling of MSW. In this paper, ingredient, heating value and their temporal varying trends of typical MSW in Beijing were continuously measured and analyzed. With consideration of the process in pyrolysis and incineration, correlation between physical ingredients and heating values was induced, favorable for evaluation of heating value needed in handling of MSW from simple analysis of physical ingredients of it.

Effects of Neutron Skin Thickness in Peripheral Nuclear Reactions

Effects of neutron skin thickness in peripheral nuclear collisions are investigated using the statistical abrasion ablation (SAA) model. The reaction cross section, neutron (proton) removal cross section, one-neutron (proton) removal cross section as well as their ratios for nuclei with different neutron skin thickness are studied. It is demonstrated that there are good linear correlations between these observables and the neutron skin thickness for neutron-rich nuclei. The ratio between the (one-)neutron and proton removal cross section is found to be the most sensitive observable of neutron skin thickness. Analysis shows that the relative increase of this ratio could be used to determine the neutron skin size in neutron-rich nuclei.

The influence of Multi-Step Sequential Decay on Isoscaling and Fragment Isospin Distribution in GEMINI Simulation

Extensive calculations on isoscaling behavior with the sequential-decay model GEMINI are performed for the mediate-heavy nuclei in the mass range A=110 and at excitation energies of up to 3 MeV per nucleon.Isoscaling can still be observed after entire−step decays are considered for the light products as in the only first-step decay process case.Comparison between the products after the first-step decay and the ones after entire-step decay demonstrates that multi-step secondary sequential decay strongly influences the isoscaling parametersα,βas well as the fragment isospin distribution.After entire−step decays,the isoscaling parametersαandβare decreased and the fragment isospin distribution can better reproduce the isospin distribution shape as the experimental data.

Analysis of energy autocorrelation functions in dissipative heavy ion collision of ^(27)Al+^(27)Al

The excitation functions were measured in the reaction of 27Al+27Al at incident energies from 114MeV to 127MeV in steps of 200keV. The detection angles were continuously covered from 10o to 57° in the laboratory system. The energy autocorrelation functions of the dissipative fragments were analyzed by using different approaches. The nonself-averaging oscillations in the excitation functions were considered due to the angular momentum coherence and damping of the coherent nuclear rotation. The damping results from a quantum chaotic motion.

Non-equilibrium Statistic Features in Dissipative Heavy Ion Collision ^(27)Al+ ^(27)Al

The excitation functions of dissipative products have been measured in the reaction 27Al+27Al at incident energies from 114 to 127MeV in steps of 200keV. Detection angles vary continuously from 10.4° to 57.4° in laboratory system. An angular coherent width more than 40° in center of mass is obtained. The results from the analysis of excitation functions with nonself-averaging are characterized by a quasi-periodic long-range energy structure embedded in the disorder Ericson fluctuation.

北京松山落叶阔叶林生态系统水热通量对环境因子的响应

温带森林生态系统水热通量在多时间尺度上受各种生物物理因子的影响。该研究假设这些因子对水热通量的影响机制具有时间尺度分异性,通过涡度相关法(EC)于2019年全年对北京松山典型天然落叶阔叶林生态系统蒸散发(ET)、显热通量(H)、潜热通量(LE)、土壤热通量(G)、饱和水汽压差(VPD)、空气温度(T_(a))、光合有效辐射(PAR)、归一化植被指数(NDVI)及10 cm深度土壤水分(VWC)等要素进行原位连续监测,使用小波分析的方法分析了日、季节尺度上生物与非生物因子对生态系统能量分配与水汽交换的调控机制。主要研究结果:2019年松山天然落叶阔叶林生态系统年均波文比(β)为1.53。ET具有明显的季节变化特征,从第100天开始逐渐增加,7月达到峰值,第300天下降到最低水平。ET最大日累计值为5.01 mm·d^(-1),年累计值为476.2 mm,年降水量为503.3 mm。在日尺度上水热通量与VPD间滞后时间最短,为3.36 h。在季节尺度上与PAR间滞后时间最短,为8天。季节尺度上PAR通过VPD来对ET造成间接影响,而对β造成直接影响。该研究发现不同时间尺度上水热通量与环境因子间的时滞关系,为选择模型在不同时间尺度下北方温带落叶阔叶林生态系统过程的最佳输入参数提供科学支持。