重载荷RV减速机基于动力学模型的固有频率特性及灵敏度分析

采用集中参数法建立了16自由度的重载RV减速机动力学模型。以RV-550E型重载减速机为研究对象，通过求解动力学方程得到减速机的固有频率，分析了针齿壳刚度对系统固有频率的影响，为针齿壳的设计提供依据。为了揭示系统参数的变化对整机固有特性影响的规律，进一步分析整机固有频率对系统的转动惯量和刚度的灵敏度。分析结果表明，低阶固有频率对曲柄轴转臂轴承刚度、行星架支撑轴承刚度以及曲柄轴转动惯量的灵敏度较大。研究结果为该类重载减速机结构优化设计提供了理论依据

Life Cycle Assessment of Biodiesel Produced from Soybean and Waste Cooking Oil

对以大豆油和地沟油为原料制备的生物柴油进行全生命周期评价,估算了生物柴油全生命周期各过程的能源消耗及周期排放。对以大豆油和地沟油为原料生产生物柴油的生命周期进行了对比,结果表明：以地沟油为原料生产生物柴油的全生命周期总能耗约为以大豆油为原料能耗的1/8,其周期排放也低于大豆油生产的生物柴油,CO2、SO2、NOx、CO、CH4、VOC、烟尘、PM10和固体废弃物各项排放较大豆油为原料分别降低14.2%、56.7%、4.9%、46.3%、96.5%、98.5%、18.8%、61.9%和10.1%。制备生物柴油的CO2排放远远小于化石柴油的排放,其中大豆油生物柴油降低83.5%,地沟油生物柴油降低85.9%,以地沟油为原料制备生物柴油比以大豆油为原料更具优势

电动汽车能耗与气体排放分析及环境影响评价

以普瑞斯、比亚迪E6分别作为混合动力汽车和纯电动汽车代表,利用生命周期评价方法,对电动汽车制造、使用、报废回收3个主要阶段进行了环境成本、能耗和环境影响潜值评价,并与以桑塔纳为代表的传统燃油汽车的相应结果进行比较分析.结果表明:在生命周期内,纯电动汽车的环境成本最低,其次是混合动力汽车,传统燃油汽车的最高,其中纯电动汽车的环境成本仅为燃油汽车的36.04%.混合动力汽车和纯电动汽车在全生命周期过程中总能耗分别是传统燃油汽车的59.92%和52.20%.车辆行驶阶段,电动汽车的能耗较低,而在车辆制造和废弃回收阶段它们的能耗则更高.混合动力汽车和纯电动汽车全生命周期的加权总环境影响潜值分别为传统燃油汽车的56.72%和34.16%.混合动力汽车的环境影响负荷与传统燃油汽车的类似,主要来自于光化学烟雾,而纯电动汽车环境影响负荷则主要来自于粉尘、全球变暖和光化学烟雾三个方面

JUNO Sensitivity on Proton Decay p→νˉK+p\to \bar\nu K^+ Searches

The Jiangmen Underground Neutrino Observatory (JUNO) is a large liquid scintillator detector designed to explore many topics in fundamental physics. In this paper, the potential on searching for proton decay in $p\to \bar\nu K^+$ mode with JUNO is investigated.The kaon and its decay particles feature a clear three-fold coincidence signature that results in a high efficiency for identification. Moreover, the excellent energy resolution of JUNO permits to suppress the sizable background caused by other delayed signals. Based on these advantages, the detection efficiency for the proton decay via $p\to \bar\nu K^+$ is 36.9% with a background level of 0.2 events after 10 years of data taking. The estimated sensitivity based on 200 kton-years exposure is $9.6 \times 10^{33}$ years, competitive with the current best limits on the proton lifetime in this channel

JUNO sensitivity on proton decay p → ν K + searches*

The Jiangmen Underground Neutrino Observatory (JUNO) is a large liquid scintillator detector designed to explore many topics in fundamental physics. In this study, the potential of searching for proton decay in the $p\to \bar{\nu} K^+$ mode with JUNO is investigated. The kaon and its decay particles feature a clear three-fold coincidence signature that results in a high efficiency for identification. Moreover, the excellent energy resolution of JUNO permits suppression of the sizable background caused by other delayed signals. Based on these advantages, the detection efficiency for the proton decay via $p\to \bar{\nu} K^+$ is 36.9% ± 4.9% with a background level of $0.2\pm 0.05({\rm syst})\pm$$0.2({\rm stat})$ events after 10 years of data collection. The estimated sensitivity based on 200 kton-years of exposure is $9.6 \times 10^{33}$ years, which is competitive with the current best limits on the proton lifetime in this channel and complements the use of different detection technologies