高校基础化学实验准备工作精细化——以武汉大学为例

基础化学实验面向全校化学、近化学等多个学科专业开设,学生人数多、涉及专业广、仪器药品种类多数量大,繁琐的实验准备工作是很多专技人员面临的不小挑战。科学、精细的实验准备工作,不仅能降低劳动强度,提高工作效率,而且能有力支撑实验教学,提高教学质量。本文结合武汉大学基础化学实验课程的实验准备工作,详细介绍了系列精细化举措,并通过若干具体实例展示精细化实施细节,方便应用推广。

Genetic relationship between formation,accumulation and migration and dispersion of peat materials in Paleogene——Take the Qiongdongnan Basin as an example

Coal-type source rocks include both coal and terrigenous marine source rocks.By studying the distribution of secondary depressions,uplifts,as well as the characteristics of peat formation and accumulation in the northern marginal sea basin of the South China Sea,and combining them with coal formation characteristics observed in other basins,five genetic theories on the relationship between peat accumulation and dispersed organic matter accumulation are proposed.The northern marginal sea basin of the South China Sea is characterized by“disadvantageous coals formation and favorable terrigenous marine source rocks formation.”This paper provides a distribution map of coal seams and terrigenous marine source rocks in the Qiongdongnan Basin and determines their distribution patterns.Research shows that the migration of sedimentary facies in the basins and inner depressions led to the formation and migration of the peat accumulation centers.In addition,the vertical migration of the peat accumulation centers led to planar migration,which is actually a type of coupling relationship.Previous research results have revealed that the formation of coal-type source rock is multi-phased.The marginal sea basin is composed of several fault-depression basins,with each basin developing a second order of depression and uplift.There is no unified basin center or depositional center to be found.As a result,the concentration centers of coal-forming materials also vary greatly.Based on the distribution characteristics of coal-type source rocks in different basins within the marginal sea basins of the South China Sea,the research results have practical significance and provide guidance for exploring coal-type oil and gas reservoirs in this area.

Edaravone-loaded poly(amino acid) nanogel inhibits ferroptosis for neuroprotection in cerebral ischemia injury

Neurological injury caused by ischemic stroke is a major cause of permanent disability and death. The currently available neuroprotective drugs fail to achieve desired therapeutic efficacy mainly due to short circulation half-life and poor blood−brain barrier (BBB) permeability. For that, an edaravone-loaded pH/glutathione (pH/GSH) dual-responsive poly(amino acid) nanogel (NG/EDA) was developed to improve the neuroprotection of EDA. The nanogel was triggered by acidic and EDA-induced high-level GSH microenvironments, which enabled the selective and sustained release of EDA at the site of ischemic injury. NG/EDA exhibited a uniform sub-spherical morphology with a mean hydrodynamic diameter of 112.3 ± 8.2 nm. NG/EDA efficiently accumulated at the cerebral ischemic injury site of permanent middle cerebral artery occlusion (pMCAO) mice, showing an efficient BBB crossing feature. Notably, NG/EDA with 50 µM EDA significantly increased neuron survival (29.3%) following oxygen and glucose deprivation by inhibiting ferroptosis. In addition, administering NG/EDA for 7 d significantly reduced infarct volume to 22.2% ± 7.2% and decreased neurobehavioral scores from 9.0 ± 0.6 to 2.0 ± 0.8. Such a pH/GSH dual-responsive nanoplatform might provide a unique and promising modality for neuroprotection in ischemic stroke and other central nervous system diseases.

Mechanism of principal stress rotation and deformation failure behavior induced by excavation in roadways

The failure modes of rock after roadway excavation are diverse and complex.A comprehensive investigation of the internal stress field and the rotation behavior of the stress axis in roadways is essential for elucidating the mechanism of roadway failure.This study aimed to examine the spatial relationship between roadways and stress fields.The law of stress axis rotation under three-dimensional(3D)stress has been extensively studied.A stress model of roadways in the spatial stress field was established,and the far-field stress state at different spatial positions of the roadways was analyzed.A mechanical model of roadways under a 3D stress state was established using far-field stress solutions as boundary conditions.The distribution of principal stressesσ1,σ2 andσ3 around the roadways and the variation of the stress principal axis were solved.It was found that the stability boundary of the stress principal axis exhibits hysteresis when compared with that of the principal stress magnitudes.A numerical analysis model for spatial roadways was established to validate the distribution of principal stress and the mechanism of principal axis rotation.Research has demonstrated that the stress axis undergoes varying degrees of spatial rotation in different orientations and radial depths.Based on the distribution of principal stress and the rotation law of the stress principal axis,the entire evolution mechanism of the two stress adjustments to form the final failure form after roadway excavation has been revealed.The on-site detection results also corroborate the findings presented in this paper.The results provide a basis for the analysis of the failure mechanism under a 3D stress state.

Revealing the role of honokiol in human glioma cells by RNA-seq analysis

Background:Glioma is a kind of tumor that easily deteriorates and originates from glial cells in nerve tissue.Honokiol is a bisphenol compound that is an essential monomeric compound extracted from the roots and bark of Magnoliaceae plants.It also has anti-infection,antitumor,and immunomodulatory effects.In this study,we found that honokiol induces cell apoptosis in the human glioma cell lines U87-MG and U251-MG.However,the mechanism through which honokiol regulates glioma cell apoptosis is still unknown.Methods:We performed RNA-seq analysis of U251-MG cells treated with honokiol and control cells.Protein-protein interaction(PPI)network analysis was performed,and the 10 top hub unigenes were examined via real-time quantitative PCR.Furthermore,MAPK signaling and ferroptosis were detected via western blotting.Results:332 differentially expressed genes(DEGs)were found,comprising 163 increased and 169 decreased genes.Analysis of the DEGs revealed that various biological processes were enriched,including‘response to hypoxia’,‘cerebellum development cellular response to hypoxia,’‘iron ion binding,’‘oxygen transporter activity,’‘oxygen binding,’‘ferric iron binding,’and‘structural constituent of cytoskeleton.’Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway analysis revealed that the DEGs were enriched in the following pathways:‘mitogen-activated protein kinases(MAPK)’,‘Hypoxia-inducible factor 1(HIF-1)’,‘ferroptosis,’‘Peroxisome proliferator-activated receptor(PPAR),’‘Phosphatidylinositol-4,5-bisphosphate 3-kinase(PI3K)-protein kinase B(Akt),’and‘phagosome.’Among these pathways,the MAPK signaling pathway and ferroptosis were verified.Conclusion:This study revealed the potential mechanism by which honokiol induces apoptosis and provided a comprehensive analysis of DEGs in honokiol-treated U251-MG cells and the associated signaling pathways.These data could lead to new ideas for future research and therapy for patients with glioma.

Exploration of The Construction Path of Sports Injury and First Aid Course Systems for College Students

By the requirements of the Ministry of Education on life safety education, colleges, and universities have set up a course on Sports Injury and First Aid to organize relevant knowledge and increase the student’s awareness of first aid knowledge so that they can use reasonable methods to address sport-related injuries. At the same time, they can cope with first-aid situations and assist rescuers in completing resuscitation activities. This paper is based on the study of three colleges in Chongqing. This paper selected students from 3 universities in Chongqing and evaluated the mastery of first aid knowledge of college students, pointing out the value of implementing the “Sports Injury and First Aid” course in colleges and universities. This can provide opportunities to improve the theoretical content of the discipline, actively carry out practical activities, reasonably set the assessment method, and provide basic protection to ensure that the “Sports Injury and First Aid” course can be carried out normally to improve the mastery level of students’ first aid knowledge.

High-efficiency separation and extraction of naphthenic acid from high acid oils using imidazolium carbonate ionic liquids

N-alkyl imidazolium carbonate ionic liquids were employed to separate and recover naphthenic acid from model oils.The effects of the cationic and anionic structures of ionic liquids and operating conditions on the deacidification performance were investigated.The deacidification performance of traditional organic solvents was also investigated for comparison.The results indicated that the naphthenic acid could be completely removed from the model oil with a small mass ratio of ionic liquid to oil.The extracted naphthenic acid was regenerated with a recovery of up to 92%.In addition,imidazolium carbonate ionic liquids could be successfully regenerated and recycled.The mechanism of interaction between imidazole ionic liquids and the naphthenic acid molecules were explained by Gauss calculation.

Efficacy of repeated intravenous esketamine in adolescents with anxious versus non-anxious depression

Background Patients with anxious major depressive disorder(MDD)are more likely to have poorer outcomes than those with non-anxious MDD.However,the effect of esketamine on adolescents with anxious versus non-anxious MDD has remained unknown.Aims We compared the efficacy of esketamine in adolescents with MDD and suicidal ideation,both anxious and non-anxious.Methods Fifty-four adolescents with anxious(n=33)and non-anxious(n=21)MDD received three infusions of esketamine 0.25mg/kg or active-placebo(midazolam 0.045 mg/kg)over 5 days,with routine inpatient care and treatment.Suicidal ideation and depressive symptoms were assessed using the Columbia Suicide Severity Rating Scale and the Montgomery-Asberg Depression Rating Scale.Multiple-sample proportional tests were used to compare the differences between groups on treatment outcomes 24 hours after the final infusion(day 6,primacy efficacy endpoint)and throughout the 4-week post-treatment(days 12,19 and 33).Results In subjects who received esketamine,a greater number of patients in the non-anxious group than the anxious group achieved antisuicidal remission on day 6(72.7%vs 18.8%,p=0.015)and day 12(90.9%vs 43.8%,p=0.013),and the non-anxious group had a higher antidepressant remission rate compared with the anxious group on day 33(72.7%vs 26.7%,p=0.045).No significant differences in treatment outcomes were observed between the anxious and non-anxious groups at other time points.Conclusions Three infusions of esketamine as an adjunct to routine inpatient care and treatment had a greater immediate post-treatment antisuicidal effect in adolescents with non-anxious MDD than in those with anxious MDD;however,this benefit was temporary and was not maintained over time.

Geochronological and geochemical constraints on the granitic gneiss in the Huozhou Complex: implications for the tectonic evolution of the Trans-North China Orogen

The Trans-North China Orogen is a major Neoarchean Paleoproterozoic collisional orogenic belt above the North China Craton, formed due to prolonged and complex processes. Even though many NeoarcheanPaleoproterozoic magmatic and metamorphic activities have been reported, due to the Huozhou Complex’s small outcropping range, little attention has been paid to the origin of various igneous rocks of the Huozhou Complex in the center of the Trans-North China Orogen. The Huozhou Complex, located south of the Luè liang, Wutai, and Hengshan complexes, is an important window into the Early Precambrian structure and evolution of the North China Craton. Its magma and metamorphism are crucial to understanding the development of the structural evolution of the Trans-North China Orogen. The Huozhou metamorphic complex area exposes a range of Precambrian metamorphic rocks, among which the most extensively dispersed is felsic biotite plagioclase gneiss. In this study comprehensive geological field survey, micropetrology,chronology, geochemistry, and Hf isotope analysis were carried out for the Qinggangping and Anziping gneiss in the north of the Huozhou Complex. The results show that the magmatic zircon age of the Qinggangping gneiss is2196 ± 14 Ma, and its protolith is I-type granite, formed by partial melting of igneous rocks in the absence of weathering. Its source is mainly the juvenile crust from depleted mantle dating 2431–2719 Ma, with a small amount of mantle-derived material. The Anziping gneiss has a metamorphic zircon age of 1931 ± 13 Ma with an S-type granite protolith belonging to peraluminous granite.The Anziping gneiss is formed by recycling pre-existing crustal components at 2613–2848 Ma. A minor quantity of mantle-derived magma is also introduced to the crust simultaneously. The samples of Qinggangping gneiss and Anziping gneiss show the characteristics of obvious negative Nb, Ti, and P elements in the spider diagram of primitive mantle standardization. This implies that the rocks have the characteristics of magmatic rocks in an island arc or subduction environment, which could have formed in the tectonic environment of the continental margin arc.

2.7-Ga-old mafic dike in the Trans-North China Orogen of the North China Craton and its tectonic significance

We studied an Archean mafic dike in the TransNorth China Orogen of the North China Craton, which has a magmatic age of 2701 ± 83 Ma and is currently the oldest mafic dike in the North China Craton. Such an old dike is extremely rare in the world. The presence of mafic dikes indicates that the North China Craton was in a tensional tectonic environment at 2.7 Ga. Geochemical characteristics reveal that this mafic dike belongs to continental tholeiitic basalt. Results from Hf isotope analysis reveal that the mafic dike originates from a depleted mantle. The plate assembly in the North China landmass was realized during the Archean era(2.7 Ga), and a thick and stable continental crust was formed. Therefore, the first cratonization of the North China Craton was completed before 2.7 Ga. The intrusion of the 2.7-Ga-old mafic dike from the deep lithospheric mantle of the continent indicates that the North China Craton has undergone a period of extensional tectonic activity. This event marks a significant extensional event that occurred after the cratonization of the North China Craton.

新农科背景下化学专业课程思政建设的探索与实践——以河北农业大学仪器分析课程教学为例

立德树人是大学的立身之本,新农科背景下积极推动课程思政建设,是当今教学改革的重中之重。发挥农林院校特色,将仪器分析化学专业课程与思政育人有机融合,从课程思政元素挖掘、思政典型案例设计、思政改革实施手段与路线等方面进行了探索与实践,遵循“两性一度”的标准,努力构建新时代思政育人“金课”,达到培养创新型、复合型、应用型、知农爱农的新型农林人才的目的。

基于虚拟仿真实验的锂离子电池正极材料制备及性能探究

随着我国新能源行业的迅猛发展,不少高校开设了锂离子电池材料的制备、表征、电池组装和性能测试等综合实验,取得了很好的教学效果。但是由于设备成本和教学时间的限制,无法满足全部实验需求。我们采用虚拟仿真技术,通过虚拟实验过程中正极材料的制备、锂离子电池的组装和性能测试的完整流程,让学生熟悉电化学实验的基本操作技能和相关仪器的使用方法,进而在实际操作中提高实验效率和成功率,建立了虚实结合、线上线下融合的教学模式,拓宽了学生的视野,培养了学生的动手能力和创新意识。

压缩学时背景下无机化学教学改革

在无机化学教学学时压缩的背景下,综合考虑我国中学化学课程改革及目前无机化学教学所面临的问题,适度调整、拓宽和深化无机化学教学内容,并基于OBE理念,采用"模块化"教学、"分层化"教学及"专题研讨式"教学,培养学生自主学习能力、解决实际问题的能力以及创新能力,形成"知识-能力"一体化的教育理念。

浅谈几种同分异构体的质谱解析

质谱解析是波谱分析课程教学的重点和难点,有机化合物裂解规则是质谱解析的关键,掌握有机化合物质谱的碎裂规律对于化合物结构解析很有帮助。本文从本科教学的实际出发,对三类常见同分异构体羧酸-酯、醇-醚及直链-支链化合物的质谱碎裂规律进行梳理,并通过具体质谱解析实例帮助学生学习、掌握有机化合物的基本裂解规律,提高质谱解析能力。

纳米金的故事——见微知著

金元素在人类科学技术发展中占有重要的地位。卢瑟福通过向金箔发射α粒子,弄清了原子的基本结构;法拉第的胶体金实验为今天的纳米技术革命提供了早期的线索;金电极用于制备引发信息革命的芯片。而纳米金是黄金技术发展的核心,比如诊断测试工具,等离子体效应以及高效催化剂。本文结合实例,用生动的语言对纳米金的历史、应用和未来发展进行了论述和概括,同时也介绍了相关的物理化学原理,让读者在趣味阅读中了解纳米金的相关知识和应用。

课程思政融入分析化学课堂的实践与思考

课程思政是高等学校实现思想政治教育工作贯穿育人全过程的重要途经。本文介绍了华东理工大学在分析化学教学中开展课程思政的整体思路和实践思考。根据分析化学学科特点,选择合适的分析化学知识点对接至思想政治课程的相关内容,通过构建思政案例库,挖掘学科前沿中的思政元素,开展灵活多样的全覆盖思政教学等具体措施与手段。将专业知识与思政教育有效融合,使思政教育内容自然渗透并融入课堂教学中,培养和深化学生在家国情怀和文化自信、科学精神、公民意识、健全人格等各方面的意识与能力。

以学生为主体的混合式个性化教学模式在分析化学课程中的探索与思考

针对传统教学方法在本科基础理论课程教学中存在的问题与缺陷,以分析化学课程为例,提出以学生为主体的个性化教学为切入点的理念,对目前实行的混合式教学模式进行设计与思考,并对可以实行的辅助手段进行探索,希望从真正意义上增强人才培养的针对性和适用性。

分析化学慕课课程平台的快速构建及教学实施方法探索

针对新型冠状病毒感染肺炎疫情对高校正常开学和课堂教学造成的影响,本校分析化学教研室积极响应教育部高等学校化学类专业教学指导委员会的倡议,快速筹备与构建了基于校内多层次信息化学习平台的在线慕课教学活动,以保障延期开学期间分析化学课程的教学安排,帮助与指导选课学生在疫情防控期间高效高质量地完成本课程的学习。本文从分析化学慕课课程的快速构建与特点,校内课程平台的学习及管理,微信群、QQ群及公共邮箱等辅助教学,以及学生的使用效果与学习诉求等几个方面进行探析,希望为提高分析化学的教学质量,探索新型教学方法提供数据支持,从而与学生一同完成课程的教学与学习,收获理想的成绩。

《西北师范大学附属小学发展事略》述评

《西北师范大学附属小学发展事略》立足小学的发展历程,以国家教育方针政策为指导,与我国教育发展史以及地方文化紧密结合。通过回望西北师范大学附属小学的历史、还原其现代化建设全貌,流露出人文主义的精神价值和情感趋向,在整理保存史料、完善教育体系建设、传承优秀传统文化等诸多方面具有极其重要的现实作用。

探讨维生素B_(12)研究史中的思政元素

维生素B_(12)的研究史蕴含了丰富的思政元素。本文通过探究维生素B_(12)的发现、治疗恶性贫血机理、结构测定、人工合成、生物合成中的关键人物、事件,凝练出弘扬中医药学、用科学造福人类、团队合作、持之以恒、创新精神等五大思政元素,以期为相关专业课程中课程思政的开展带来有益的启迪。