慕课在《有机化学》教学中实践研究

有机化学是临床医学专业重要的基础课程。针对有机化学课程内容庞杂,难于掌握等特点,采用慕课网络在线教学方法、创建QQ学习平台、制作实验教学视频、混合式讲授方式等措施进行有机化学教学改革。将网络教学与传统教学模式相结合,探索提高有机化学教学效果的创新方法。在试点班级的课程实践结果表明在有机化学课程中应用慕课可以有效地提高学生的学习成绩,达到了预期的教学目标。     

慕课时代的有机化学实验教学改革初探

针对当前有机化学实验教学现状,提出了一系列的有效途径以激发学生的学习热情,有效地提高实验课程的教学质量,具体内容包括精选实验教学内容、推广微型实验、将慕课引进实验教学、规范实验报告的撰写和构建合理的考核方案等实验教学改革方案,最后对有机化学实验教学改革的未来进行了展望。     

慕课在短学时有机化学教学中的应用

有机化学是高等院校生物工程专业的一门必修基础课。高校课程改革压缩了有机化学的学时数,但有机化学课程内容复杂,记忆量大,易混淆,传统的有机化学教学模式已收效甚微。将慕课教学引入传统教学中,通过慕课网络教学平台进行辅助教学,引导学生自主学习、自主探究问题、自主解决问题,借此提高教学效果和教学质量。     

应用型人才培养背景下基于慕课的自主学习在有机化学实验教学中的实践

有机化学实验课是应用型人才培养的一条重要途径。本文结合地方应用型本科大学学生特点和有机化学实验课程的特点,将慕课资源引入到有机化学实验的教学中,引导学生自主学习。慕课资源的选择、教学实施、教学效果和存在的问题与启示等方面进行了探讨。结果显示,基于慕课平台的学生自主学习为主的教学方法,提高了学生探究问题、解决问题的能力,有利于应用型人才的培养。     

慕课在《有机化学实验》教学中的应用

有机化学实验是高等院校化学类专业的一门必修基础实验课,其目的是培养学生的操作技能,也是培养学生的科学素质与态度、创新能力和创新思维的重要环节。针对有机化学实验存在耗时长,操作复杂,记忆量大等问题和不足,在有机化学实验中通过制作实验基本操作视频及制作精选的实验教学视频,并采用慕课网络教学平台进行实验辅助教学,以提高教学效率和教学质量。     

高等农业院校应化专业有机化学实验慕课教学改革初探

有机化学实验是高等农业院校应化专业重要的基础实验课。结合应化专业有机化学实验的教学实际,作者对有机化学实验慕课教学进行了初步探索,以提高教学效率和教学质量。     

慕课在无机化学实验教学中的应用

无机化学实验是高等院校化学专业的一门基础实验课，在实验教学过程中存在学生操作能力不足，危险化学品使用数量多存在安全隐患，尤其是新冠疫情影响实验课程的正常开设等问题。为解决以上问题，将慕课与无机化学实验相结合，通过制作实验教学视频，采用慕课平台进行辅助教学，并基于慕课平台优化原有的实验考核方法，提高无机化学实验课程的教学效率及质量。     

基于慕课的融合式教学在有机化学实验中的应用

传统的有机化学实验课堂教学存在学生学习兴趣不高和主动学习能力弱等问题。本文探索将慕课与传统课堂教学相结合的融合教学模式应用于有机化学实验课程中,有效衔接教师的引导与学生的主动学习。结果表明,基于慕课的融合式教学有助于激发学生的学习兴趣,提高学生的自主学习能力,从而有效提高有机化学实验课程的教学效率及质量。     

“翻转课堂教学”应用于基础化学实验教学

计算机和互联网的普及使"翻转课堂教学"的实施变得可行;慕课是在线开放的共享网络课程平台。将慕课—翻转课堂应用于基础化学实验可以增加学生学习的兴趣、提高学生学习的主观能动性。在实验教学过程中,将慕课—翻转课堂与传统教学相结合,遵从"循序渐进"的原则。     

慕课时代有机化学混合式教学模式的探究

分析了传统有机化学教学模式面临的基本问题,并对慕课时代教学模式进行了探讨,从而构建了传统课堂教学与慕课教学相结合的混合式教学模式,将信息化融入有机化学课堂,使教学手段更加高效,教学资源更加丰富,评价考核更加客观,学生的学习更加主动。实践证明,这种混合式教学模式有效提升了教学效率和质量,更进一步提高了学生的自主学习的能力。     

Many Drugs of Abuse May Be Acutely Transformed to Dopamine,Norepinephrine and Epinephrine In Vivo

It is well established that a wide range of drugs of abuse acutely boost the signaling of the sympathetic nervous system and the hypothalamic–pituitary–adrenal (HPA) axis, where norepinephrine and epinephrine are major output molecules. This stimulatory effect is accompanied by such symptoms as elevated heart rate and blood pressure, more rapid breathing, increased body temperature and sweating, and pupillary dilation, as well as the intoxicating or euphoric subjective properties of the drug. While many drugs of abuse are thought to achieve their intoxicating effects by modulating the monoaminergic neurotransmitter systems (i.e., serotonin, norepinephrine, dopamine) by binding to these receptors or otherwise affecting their synaptic signaling, this paper puts forth the hypothesis that many of these drugs are actually acutely converted to catecholamines (dopamine, norepinephrine, epinephrine) in vivo, in addition to transformation to their known metabolites. In this manner, a range of stimulants, opioids, and psychedelics (as well as alcohol) may partially achieve their intoxicating properties, as well as side effects, due to this putative transformation to catecholamines. If this hypothesis is correct, it would alter our understanding of the basic biosynthetic pathways for generating these important signaling molecules, while also modifying our view of the neural substrates underlying substance abuse and dependence, including psychological stress-induced relapse. Importantly, there is a direct way to test the overarching hypothesis: administer (either centrally or peripherally) stable isotope versions of these drugs to model organisms such as rodents (or even to humans) and then use liquid chromatography-mass spectrometry to determine if the labeled drug is converted to labeled catecholamines in brain, blood plasma, or urine samples.     

ICP-MS法测定地球化学样品中As、Cr、Ge、V等18种微量痕量元素的研究

建立了测定地球化学样品中包括As、Cr、Ge、V等18种微量、痕量元素的ICP-MS方法。地化试样用HF-HNO3混酸分解后,以1 1 HNO3溶解干渣。由于制样不使用盐酸,避免了Cl对As、Cr、Ge、V的质谱干扰。用国家一级地球化学标准物质GBW 07309制备溶液优化仪器工作参数,并用于校准。方法测定限(6s)为:0.007~6.4μg/g,精密度(RSD%,n=12)为:29%~9.4%,经过国家一级地球化学标准物质的分析验证,结果与标准值吻合。方法已应用于国土资源调查的试样分析。     

Insect antifeedant properties of anthranoids from the genusVismia

Vismiones and ferruginins, representatives of a new class of lypophilic anthranoids from the genusVismia were found to inhibit feeding in larvae of species ofSpodoptera, Heliothis, and inLocusta migratoria.     

Direct observation of freeze-thaw instability of latex coatings via high pressure freezing and cryogenic SEM

Despite its industrial importance, the subject of freeze-thaw (F/T) stability of latex coatings has not been studied extensively. There is also a lack of fundamental understanding about the process and the mechanisms through which a coating becomes destabilized. High pressure (2100 bar) freezing fixes the state of water-suspended particles of polymer binder and inorganic pigments without the growth of ice crystals during freezing that produce artifacts in direct imaging scanning electron microscopy (SEM) of fracture surfaces of frozen coatings. We show that by incorporating copolymerizable functional monomers, it is possible to achieve F/T stability in polymer latexes and in low-VOC paints, as judged by the microstructures revealed by the cryogenic SEM technique. Particle coalescence as well as pigment segregation in F/T unstable systems are visualized. In order to achieve F/T stability in paints, latex particles must not flocculate and should provide protection to inorganic pigment and extender particles. Because of the unique capabilities of the cryogenic SEM, we are able to separate the effects of freezing and thawing, and study the influence of the rate of freezing and thawing on F/T stability. Destabilization can be caused by either freezing or thawing. A slow freezing process is more detrimental to F/T stability than a fast freezing process; the latter actually preserves suspension stability during freezing. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004 in Chicago, IL. Tied for first place in The John A. Gordon Best Paper Competition.     

Ethanol and (−)-α-Pinene: Attractant Kairomones for Bark and Ambrosia Beetles in the Southeastern US

In 2002–2004, we examined the flight responses of 49 species of native and exotic bark and ambrosia beetles (Coleoptera: Scolytidae and Platypodidae) to traps baited with ethanol and/or (−)-α-pinene in the southeastern US. Eight field trials were conducted in mature pine stands in Alabama, Florida, Georgia, North Carolina, and South Carolina. Funnel traps baited with ethanol lures (release rate, about 0.6 g/day at 25–28°C) were attractive to ten species of ambrosia beetles (Ambrosiodmus tachygraphus, Anisandrus sayi, Dryoxylon onoharaensum, Monarthrum mali, Xyleborinus saxesenii, Xyleborus affinis, Xyleborus ferrugineus, Xylosandrus compactus, Xylosandrus crassiusculus, and Xylosandrus germanus) and two species of bark beetles (Cryptocarenus heveae and Hypothenemus sp.). Traps baited with (−)-α-pinene lures (release rate, 2–6 g/day at 25–28°C) were attractive to five bark beetle species (Dendroctonus terebrans, Hylastes porculus, Hylastes salebrosus, Hylastes tenuis, and Ips grandicollis) and one platypodid ambrosia beetle species (Myoplatypus flavicornis). Ethanol enhanced responses of some species (Xyleborus pubescens, H. porculus, H. salebrosus, H. tenuis, and Pityophthorus cariniceps) to traps baited with (−)-α-pinene in some locations. (−)-α-Pinene interrupted the response of some ambrosia beetle species to traps baited with ethanol, but only the response of D. onoharaensum was interrupted consistently at most locations. Of 23 species of ambrosia beetles captured in our field trials, nine were exotic and accounted for 70–97% of total catches of ambrosia beetles. Our results provide support for the continued use of separate traps baited with ethanol alone and ethanol with (−)-α-pinene to detect and monitor common bark and ambrosia beetles from the southeastern region of the US.     

基于ATRP法制备的触角状亲水性羟胺树脂的吸硼性能的研究

以大分子引发剂氯乙酰化聚苯乙烯微球(PS-acyl-Cl)经原子转移自由基聚合(ATRP)法引发丙烯酰胺(AM)和甲基丙烯酸缩水甘油酯(GMA)单体的共聚接枝,制得一种触角状亲水性环氧载体(PS-acyl-g-P(AM-co-GMA)),再经二乙醇胺(DEA)的环氧基开环胺化反应,得到一种含多个-NCH2CH2OH螯合配基的多齿-五元螯合环的触角状亲水性羟胺树脂(PS-acyl-g-P(AM-co-GMA)-DEA)。将此树脂用于硼吸附研究,结果表明,PS-acyl-g-P(AM-co-GMA)-DEA树脂对硼的吸附满足Langmuir方程,为单分子层吸附;饱和吸附量约为37.7 mg·g-1,且树脂5 min即可达到吸附平衡,与其它已报道的吸硼树脂相比,该树脂具有更高的吸附量和吸硼速率。吸附动力学研究表明,树脂吸附硼的过程主要由颗粒扩散过程控制。重复使用5次后该树脂的吸附量基本不变,解吸率均在90%以上,重复使用性能良好。