探索高校实验室大型仪器设备管理新模式

高等学校大型仪器设备是从事教学、科研的重要条件和基本手段,是学校综合实力的体现。随着现代科学技术的迅猛发展,知识在经济发展中起到越来越重要的作用,使得高校大型仪器设备的管理显得尤为重要。结合工作实践,以及对目前高校实验室大型仪器设备管理及使用现状的分析,提出了加强高校大型仪器设备管理,提高大型仪器设备使用效率的若干措施。     

浅谈高职高专英语学习兴趣激发和培养的方法

高职高专学生英语基础相对薄弱,学习兴趣和信心不足,甚至放弃英语学习。激发学生学习兴趣,使其树立正确的学习目标和学习信心,对于提高语言教学效率起着至关重要的作用。帮助学生树立学习兴趣和信心,从而逐渐培养其自主学习能力的方法主要有：做好第一堂课的铺垫与引导;定期开展课堂小外语角活动,树立信心,激发兴趣;利用小游戏消除学习疲劳,唤醒学生热情;注重改变传统教学＂满堂灌＂模式,营造良好的语言学习氛围,引导学生体会英语学习的乐趣;将英美文化知识引入课堂,突出英美文化的趣味性。     

探析老年人社会参与的有效途径

目前,中国已经成为老龄化国家之一,老年人的养老问题日益突出,成为社会关注的焦点。实现老年人社会参与是对传统养老模式的有益补充,是老年人丰富晚年生活、提高生命质量的重要途径。本文针对现实养老困境并依据相关理论,从政府、社会团体及老年人自身这三方入手去探寻可操作的老年人社会参与途径。     

关于Mordell方程y^2=x^3＋k

设l,l1,l2,…,ls为任意整数,n为正整数,n1,n2,…,ns为任意非负整数．用初等数论方法证明了：如果k满足k=（4l＋2）^3-Пi=1^s（4li＋1）^2ni或k=（4l＋3）^3-2^2nПi=1^s（4li＋1）^2ni,则Mordell方程y^2=x^3＋k无整数解．     

Enabling Mg metal anodes rechargeable in conventional electrolytes by fast ionic transport interphase

Rechargeable magnesium batteries have received extensive attention as the Mg anodes possess twice the volumetric capacity of their lithium counterparts and are dendrite-free. However, Mg anodes suffer from surface passivation film in most glyme-based conventional electrolytes, leading to irreversible plating/stripping behavior of Mg. Here we report a facile and safe method to obtain a modified Mg metal anode with a Sn-based artificial layer via ion-exchange and alloying reactions. In the artificial coating layer, Mg₂Sn alloy composites offer a channel for fast ion transport and insulating MgCl₂/SnCl₂ bestows the necessary potential gradient to prevent deposition on the surface. Significant improved ion conductivity of the solid electrolyte interfaces and decreased overpotential of Mg symmetric cells in Mg(TFSI)₂/DME electrolyte are obtained. The coated Mg anodes can sustain a stable plating/stripping process over 4000 cycles at a high current density of 6 mA cm⁻². This finding provides an avenue to facilitate fast ion diffusion kinetics of Mg metal anodes in conventional electrolytes.     

发展中国电子商务的几点思考

“电子商务”这个名词在我国已经不在是陌生的名词了,它已经在中国越来越被人们所认可.什么是电子商务?所谓电子商务(ElectronicCommerce)是利用计算机技术、网络技术和远程通信技术,实现整个商务(买卖)过程中的电子化、数字化和网络化。人们不再是面对面的、看着实实在在的货物、靠纸介质单据(包括现金)进行买卖交易。而是通过网络,通过网上琳琅满目的商品信息、完善的物流配送系统和方便安全的资金结算系统进行交易(买卖)。     

Genomic diversity and post-admixture adaptation in the Uyghurs

Population admixture results in genome-wide combinations of genetic variants derived from different ancestral populations of distinct ancestry, thus providing a unique opportunity for understanding the genetic determinants of phenotypic variation in humans. Here, we used whole-genome sequencing of 92 individuals with high coverage (30–60×) to systematically investigate genomic diversity in the Uyghurs living in Xinjiang, China (XJU), an admixed population of both European-like and East-Asian-like ancestry. The XJU population shows greater genetic diversity, especially a higher proportion of rare variants, compared with their ancestral source populations, corresponding to greater phenotypic diversity of XJU. Admixture-induced functional variants in EDAR were associated with the diversity of facial morphology in XJU. Interestingly, the interaction of functional variants between SLC24A5 and OCA2 likely influences the diversity of skin pigmentation. Notably, selection has seemingly been relaxed or canceled in several genes with significantly biased ancestry, such as HERC2–OCA2. Moreover, signatures of post-admixture adaptation in XJU were identified, including genes related to metabolism (e.g. CYP2D6), digestion (e.g. COL11A1), olfactory perception (e.g. ANO2) and immunity (e.g. HLA). Our results demonstrated population admixture as a driving force, locally or globally, in shaping human genetic and phenotypic diversity as well as in adaptive evolution.     

Replication,pathogenicity, and transmission of SARS-CoV-2 in minks

Minks are raised in many countries and have transmitted severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) to humans. However, the biologic properties of SARS-CoV-2 in minks are largely unknown. Here, we investigated and found that SARS-CoV-2 replicates efficiently in both the upper and lower respiratory tracts, and transmits efficiently in minks via respiratory droplets; pulmonary lesions caused by SARS-CoV-2 in minks are similar to those seen in humans with COVID-19. We further found that a spike protein-based subunit vaccine largely prevented SARS-CoV-2 replication and lung damage caused by SARS-CoV-2 infection in minks. Our study indicates that minks are a useful animal model for evaluating the efficacy of drugs or vaccines against COVID-19 and that vaccination is a potential strategy to prevent minks from transmitting SARS-CoV-2.     

Static analysis of synchronism deployable antenna

INTRODUCTION Large antennas for space applications have some differences as compared to their counterparts de-signed and manufactured for ground usage. For a larger space antenna, the applied loads in space can be several orders of magnitude less than the gravity loading it is subjected to when being fabricated and assembled on the ground. Since the effect of gravity cannot be removed from any experimental verifica-tion performed on the ground, we must rely on the use of efficient and hig…     

英语听力、词汇和阅读理解的应试技巧

分析了英语考试中听力、词汇和阅读理解三方面试题的考试重点和难点,通过解析典型例题,提出了具体的应试技巧,认为在英语考试中解决听力、词汇和阅读理解这三类题型时,有针对性的掌握一些答题的技巧和方法不仅可以提高回答问题的效率,更能够提高考试的质量,达到事半功倍的效果。