以建设《高分子化学》优秀课程为契机,加强专业建设

通过优秀课程建设,能够带动专业建设工作和教师队伍的培养工作,使教学质量再上一个新台阶.本文以建设<高分子化学>精品课程为模板,介绍了<高分子化学>优秀课程的建设过程,通过积极与工厂进行产、学、研密切合作,在生产实习教学环节实施、教师工程实践能力培养、学生工程实践能力和实验动手能力培养等方面形成了特色,在学科体系建设、理...     

元素化学课程思政案例库建设及线上线下混合递进式教学实践

教学团队立足元素化学课程特点,设计、建设了“科学”“人文”“思政”三融合的元素化学课程思政案例库,并将之融入线上线下混合递进式教学的各个阶段和环节,以同步实现知识传授、能力培养、价值塑造三位一体的教学目标。同时,建立课程思政的集体教研制度,确保课程思政的整体性和持续性。     

“腐蚀与防腐”教学中学生实践能力的培养

针对油气储运工程专业“腐蚀与防腐”课程实践环节中存在的问题,对课程教学进行了改革,包括调整课程目标和教学内容,建设“腐蚀与防腐”实践教学基地,构建实践教学新体系等。将实践能力培养贯穿在整个课程的教学当中,培养学生动手能力与工程实践素质,为将来毕业后的工作提供基本方法、基本技能和科学思维的保障。     

基于工程认证的毕业实习教学环节建设与管理研究

首先对工程教育认证理论进行了分析,对国内外毕业实习环节的建设与管理进行了文献综述,并对其进行了归纳分析及梳理,而后结合工程认证提出高分子材料工程专业的毕业实习应该达到的指标点。分析了毕业实习存在的问题,依据工程认证指标点,提出了双导师制、考核制度及内容,在毕业实习基地建设中采用"四一建设"和"三个依托"研究方案。通过实践最终发现,此研究方法可以用于毕业实习的教学环节,且毕业实习成绩明显提高,达成度达到了0.84。     

优化教学常规环节 促进教师专业发展——“铁的重要化合物”教学全程感悟

备课、授课、课后反思是课堂教学活动的常规环节。结合一节公开课的课前准备、教学实录和课后反思过程,对如何优化教学常规环节,实现优质、高效的教学,促进教师专业发展,进行了一些思考和探索。     

高分子材料与工程专业实践教学改革研究与探索

实践教学是培养大学生创新精神、创新能力和实践能力的最重要教学环节。本文阐述了高分子材料与工程专业实践教学的现状和存在的问题,总结了实验教学、生产实习、毕业设计这三大实践教学环节在人才培养过程中的重要作用。针对实践教学存在的问题和不足,我们着力构建新的培养模式和实践教学环境,增加研究性、探索性实践教学内容比例等,为培养具...     

微格教学培养高师生师范技能有效性的研究

以化学师范技能比赛的选手为观察研究对象,分析了高师生教学技能的差异性,探讨了微格教学与师范技能之间的关系。结果显示:高师生整体教学水平良好;在模拟上课、板书设计和即席演讲环节中,高师生在年级与教材等级上不存在显著性差异;微格学业等级分组中,高分组与低分组在模拟上课环节、板书设计与即席演讲环节上存在显著性差异。曲线回归拟合也表明,微格教学对师范教学技能有正向促进作用。     

高分子化学教学改革探索

高分子化学是高分子材料专业最重要的专业基础课之一,课程内容包含基础理论和实验教学,对后续其他专业课程的学习有直接的影响。任课教师积极探索高分子化学的教学改革,对提高教学质量和教学效果具有很重要的意义。本文结合近年来对高分子化学课程教学各环节的探索与思考,从课程建设目标、教学思路、实验与实践教学、考核方式等几个方面进行了探讨,并通过在教学实践中加以应用,调动学生的学习积极性,有效提高了教学效果和学生的综合素质。     

“两基双导分段式”实践教学体系在环境工程专业中的构建

根据韶关学院发展规划和人才培养定位,为造就一批应用型创新人才,实践教学环节显得尤为重要。本文分析了环境工程专业实践教学环节中存在的主要问题,结合韶关学院环境工程专业实践教学的具体情况,提出了构建"两基双导分段式"实践教学体系,从实践教学内容、实践教学质量保障体系、实践教学运行保障体系三方面进行创新改革,对提高大学生的工程实践能力、创新能力和综合素质起到了良好的推动作用。     

思政元素与高分子化学课程的有机融合

将思政元素与教学内容有机融合是实现“立德树人”的有效举措。本文分别从高分子化学理论和实验教学入手,以学生为中心、产出为导向,构建思政目标,设计思政环节,对典型教学思政案例进行剖析,采用调查问卷和产出效果评价课程思政建设情况。结果表明,通过将思政元素有机融入在教学中,不仅加深了学生对专业知识的理解,而且提高了学生的思想政治素养。     

Ab initio studies of the conformations of ethynyl formate, cyano formate and related ethynyl and cyano compounds

The optimized geometries, relative free energies and related thermodynamic properties, harmonic frequencies, and dipole moments have been calculated at the HF and MP2 levels for ethynyl formate (1a), ethynyl acetate (1b), cyano formate, HCO₂CN (1c), cyano acetate (1d), S-ethynyl thioformate (2a), S-ethynyl thioacetate (2b), S-cyano thioformate (2c), S-cyano thioacetate (2d), N-ethynylformamide (3a), N-ethynylacetamide (3b), N-cyanoformamide (3c), and N-cyanoacetamide (3d) with the gaussian 98 program. For ethynyl formate, the calculation for 25 °C at the MP2/6-311++G(df,pd) level predicts that the Z isomer is more stable by 1.23 kcal/mol. For S-ethynyl thioformate, calculations at the MP2/6-311++G(2d,2p) level predict that the E isomer is favored by 0.71 kcal/mol at 25 °C. The E isomers of N-ethynylformamide and N-ethynylacetamide were found at all levels to be more stable than the Z isomers at 25 °C. For cyano formate and cyano acetate, calculations at the MP2/6-311++G(df,pd) level predict that the Z isomers are more stable at 25 °C by 1.50 and 2.72 kcal/mol, respectively. At this level and temperature, the Z isomers of 2c, 2d, 3c, and 3d are predicted to have free energies of 0.46, −0.07, 1.22, and 2.28 kcal/mol, respectively, relative to the E conformations. Z to E free-energy barriers at 25 °C of 8.63, 10.64, 17.63, 7.39, and 14.03 kcal/mol were calculated for 1a, 2a, 3a, 1c, and 3c at the HF/6-311G(d,p) level, and at the HF/6-311+G(d,p) level, the free-energy barrier for 2c was 7.08 kcal/mol.     

Characteristics of Lipids from Individual Organs of Veronica beccabunga

Lipids from various organs of the aquatic plant Veronica beccabunga were studied. It has been demonstrated that neutral and polar lipids are qualitatively typical of higher photosynthetic plants. Lipids in various organs of aquatic veronica were unevenly distributed. The most significant differences were observed in neutral lipids for the accumulation of glycerin esters, free fatty acids, alcohols, and hydrocarbons. The ratio of phospholipids varied considerably in the polar lipids.     

Elucidation of activity of copper and copper oxide nanomaterials for electrocatalytic and photoelectrochemical reduction of carbon dioxide

Copper- and copper oxide–based materials are, in principle, promising components (supports, reactive sites, and visible light–absorbing semiconductors) of electrocatalysts and photocathodes for reduction of carbon dioxide. Electrochemical and photoelectrochemical approaches are generally suitable for the low-temperature CO₂-conversion to carbon-based simple organic fuels or utility chemicals.Different concepts of utilization, including nanostructuring, doping, admixing, preconditioning, modification, or functionalization of various copper- and copper oxide–based systems for catalytic electroreduction and photoelectrochemical reduction of CO₂ are elucidated, as well as important strategies to enhance the systems' overall activity and stability are discussed.     

溶质迁移研究进展

溶质迁移研究已成为水文地质等领域的一个重要研究课题。综述了溶质迁移研究进展,重点介绍了溶质迁移在地下水污染与防治、土壤盐碱化防治、海水入侵和咸水入侵防治等方面的研究现状,并指出应进一步研究的问题。     

Pyrazolones as Building Blocks in Heterocyclic Synthesis: Synthesis of New Pyrazolopyran,Pyrazolopyridazine and Pyrazole Derivatives of Expected Antifungicidal Activity

A series of new pyrazolone and pyrazole derivatives with expected antifungicidal activity have been prepared through the reactions 3‐phenyl‐1‐H‐pyrazol‐5(4H)‐one ( 3 ) and 4‐(dimethylaminomethylene)‐3‐phenyl‐1H‐pyrazol‐5(4H)‐one ( 5 ) with a variety of electrophilic reagents and nucleophilic reagents. The newly synthesized compounds were characterized by IR, ¹H NMR, ¹³C NMR and mass spectral studies.     

Studies of some monocyclic and bicyclic arylacetonitriles

The high-resolution (1)H, (13)C, (1)H-(1)H COSY and (1)H-(13)C COSY NMR spectra have been recorded in CDCl(3) for arylacetonitriles 1-12 and analyzed. The arylacetonitriles 3-7 exist in two isomeric forms E (methyl group is anti to cyano group) and Z (the methyl group is syn to cyano group) in solution. Normal chair conformation with equatorial orientations of phenyl rings at C-2 and C-6 for monocyclic nitriles 1 and 2, epimeric chair structure EC (axial configuration of methyl group at C-3) for both the E and Z isomers of arylacetonitrile derivatives (3-7) and a distorted boat form, B(3), for the N-acylacetonitrile derivatives (8-10) have been proposed based on NMR data. The bicyclic nitriles 11 and 12 exist in twin chair conformations in solution. DFT calculations and chemical shifts also support these conformations. Geometry optimizations for 1-12 were carried out according to density functional theory using B3LYP/6-31G(d,p) basis set and for 1 and 8 the theoretical geometrical parameters have been compared with those of single crystal measurements.     

Synthesis and spectral properties of malononitrile-based merocyanine dyes

Di-, tetra-, and hexamethine merocyanines derived from malononitrile and heterocycles with moderate (dyes 1–6), strong (7–9), and weak (10 and 11) electron-releasing ability were synthesized. The electronic structures of merocyanines 10 and 11 are similar to the neutral polyene state, whereas those of 7–9 are similar to the ideal polymethine state. These tendencies become more pronounced with increasing length of the polymethine chain. The merocyanines derived from heterocyclic residues with weak or moderate electron-releasing ability exhibit a positive solvatochromism, whereas those with strong electron-releasing ability show a negative solvatochromism. An increase in the polarity of the solvent makes the former compounds more similar to polymethines, whereas the latter become more similar to polyenes bearing opposite charges on the end groups. The nature of the factors (nonspecific solvation, specific nucleophilic and electrophilic solvation, and vibronic interactions) responsible for the observed characteristic features was analyzed. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2726–2735, December, 2005.     

Coupled calculation of vibrational frequencies and intensities

The combination of normal coordinate analysis with intensity calculations gives quantitative information about molecular force fields and the assignments of vibrational frequencies. Calculations of vibrational intensities by means of a standard CNDO/2 version give rise to satisfactory results for the IR intensities. However, the calculated Raman intensities often differ strongly from the experimental data. Inclusion of 2p-polarization functions on hydrogen in the usually used valence basis set is quite successful to obtain improved molecular polarizabilities as well as Raman intensities.     

Kinetic spectrophotometric determination of amodiaquine and chloroquine

Abstract  Two simple, sensitive, and selective spectrophotometric methods were developed for determining amodiaquine (AQ) and chloroquine (CQ) based on their oxidation with potassium iodate and potassium bromate, respectively. The initial rates of oxidation of AQ and CQ were monitored at 342 and 343 nm, the wavelengths of maximum absorptions of the two drugs. The various experimental parameters affecting oxidation reactions were thoroughly studied and optimized. Beer’s law was obeyed for 0.2–4.0 and 0.5–5.0 μg cm⁻³, with correlation coefficients of 0.9999 and 0.9998 (n = 6) and a detection limit (based on the 3S _b -criterion) of 0.04 and 0.06 μg cm⁻³ for AQ and CQ. The proposed methods were conveniently applied to determining AQ and CQ in pure and dosage forms. Graphical abstract        

The remarkable role of water during the chemoselective reduction of ketones mediated by metallic aluminium

Diaryl ketones are reduced selectively to the corresponding benzhydrols in good yield by aluminium powder in the presence of sodium hydroxide in the solvent system MeOH:H₂O=2:1 whereas dialkyl ketones, α-tetralone, aryl alkyl ketones and cycloalkanones remain mostly unaffected. Interestingly, diaryl ketones remain totally unchanged by the present reagent combination in the absence of water, that is in anhydrous methanol.