Available Energy Analysis of New Double-capillary Tube Refrigeration System of Refrigerator-freezer

A new double - capillary tube refrigeration system for refrigerator - freezers was proposed. A capillary tube was added between the two evaporators in the fresh and frozen food storage chests to raise the evaporation temperature of the fresh food, and reduce the heat exchange temperature difference and the available energy loss. PR equation was adopted to calculate the thermodynamic properties of the refrigerants, and the available energy analysis for the vapor compression refrigeration cycle was programmed to calculate thermodynamic performances of the new and the conventional refrigeration cycle of therefrigerator - freezer. The calculation results show that the available energy efficiency of the conventional refrigeration cycle of the refrigerator - freezer is 21.20% and 20.57%, respectively when the refrigerant is R12 and R134a while that of the double - capillary tube refrigeration cycle of the refrigerator - freezer is 23.97%and 23.44%, respectively. By comparison, the available energy efficiency of the new refrigeration system increases by 13.07% and 13.95%, respectively

卧龙国家级自然保护区食肉动物多样性及部分物种的食性分析

2018年3月—2019年1月，在卧龙国家级自然保护区三江片区和其他3个重要区域布设120个红外相机监测点对食肉动物（Carnivora）进行调查，以了解保护区内食肉动物的物种组成与垂直分布；依据粪便采样与DNA宏条形码分析，对粪便产生者及其食物种类进行鉴定，了解重要物种的食物组成和同域分布物种间的捕食关系。结果表明：在卧龙保护区共记录到13种食肉动物，其中分布海拔跨度最高的物种为猪獾（Arctonyx collaris），其次为豹猫（Prionailurus bengalensis）与黄喉貂（Martes flavigula）；分布海拔跨度最小的物种为小熊猫（Ailurus fulgens），其次为狼（Canis lupus）、大熊猫（Ailuropoda melanoleuca）与香鼬（Mustela altaica）。从群落组成的角度来看，记录到的高山食肉动物8种，包括猪獾、石貂（Martes foina）、香鼬、黄鼬（Mustela sibirica）、雪豹（Panthera uncia）、豹猫、狼与赤狐（Vulpes vulpes）；中低山食肉动物5种，包括小熊猫、大熊猫、黑熊（Ursus thibetanus）、花面狸（Paguma larvata）、黄喉貂；海拔3500 m为这2个动物群的大致分界线。在赤狐的粪便样品中共发现5个食物MOTU，主要来自鸡形目（Galliformes）、兔形目（Lagomorpha）和啮齿目（Rodentia）；豹猫样品中共发现9个食物MOTU，分别属于兔形目、啮齿目、偶蹄目（Artiodactyla）、雀形目（Passeriformes）和鸡形目。初步弄清了卧龙保护区内野生食肉动物的组成、海拔分布，结果有助于保护区食肉动物的保护与监测

Measurement of integrated luminosity of data collected at 3.773 GeV by BESIII from 2021 to 2024

We present a measurement of the integrated luminosity e+e- of collision data collected by the BESIII detector at the BEPCII collider at a center-of-mass energy of Ecm = 3.773 GeV. The integrated luminosities of the datasets taken from December 2021 to June 2022, from November 2022 to June 2023, and from October 2023 to February 2024 were determined to be 4.995±0.019 fb-1, 8.157±0.031 fb-1, and 4.191±0.016 fb-1, respectively, by analyzing large angle Bhabha scattering events. The uncertainties are dominated by systematic effects, and the statistical uncertainties are negligible. Our results provide essential input for future analyses and precision measurements