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有机化学涉及的有机反应类型繁多,反应机理复杂,理论性强,难以理解和掌握。而大学有机化学的教学模式基本以教师为中心,以课堂讲授为主,这在某种程度上束缚了学生的创造思维和积极性。融入科研的有机化学教学法的尝试,可以破解有机化学授课的困惑,调动了学生对有机化学的兴趣及精准掌握。科研渗透的教学可以拓宽学生知识视野,激发学习兴趣,实现理论联系科研、实际生产,能够加强学生对有机化学知识的掌握。 相似文献
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初学有机化学的学生,普遍感到有机化学比较难学。通过改变有机化学的教学流程,使之更符合学生的认知规律。实践过程和结果表明,新的教学流程可以帮助更多学生学好有机化学的起始课。 相似文献
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结合有机化学教材内容总结了有机化学领域的诺贝尔化学奖情况,分析了诺贝尔化学奖与有机化学及生物科学的关系,并介绍了在生物专业有机化学教学中引入诺贝尔化学奖的方法。将诺贝尔化学奖引入生物专业有机化学的教学实践有利于学生认识课程重要性,激发学习动力,提高综合素质和创新能力。 相似文献
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在多年的教学中发现,高中生初学有机化学时,所有的学生都不同程度地感到学习困难。这种状况,会持续较长的一段时间,有个别学生甚至在整个有机化学部分的学习中一直难以适应,致使学习成绩下降,影响他们的学习兴趣和信心。为探索高中生初学有机化学困难的原因,笔者进行了有关学习情况的调查,并就如何帮助学生尽快克服学习困难,提高有机化学教学质量,进行了讨论。 相似文献
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有机化学是农林院校生命、食品、农学、植保等多个学科和专业都涉及的基础性课程,在有机化学的课程教学中,学生既能够有针对性地掌握有机化学的理论知识与实验技巧,为农林方面的专业学习打下良好的基础,同时学生也能够在有机化学的教学中锻炼实验动手能力、观察能力和科学思维能力,全方位促进学生的能力提升。 相似文献
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HEPT类化合物的QSAR研究 总被引:3,自引:0,他引:3
为定量结构/活性相关性研究提取了量子化学参数,拓扑指数Am,分子连接性指数^mxt及疏水性常数,同时应用正交变换和最佳变量子集算法(Leaps-and-Bonds)进行了变量压缩和选择,进而实施了多元回归分析,并由此结果进行了HEPT类化合物(1-[(2-hydroxyethoxy)methyl]-6-(phenylthio)-thymine derivatives)的结构/活性关系的理论解释,进行了人工神经网络法对于该类化合物的活性预测,其结构明显好于多元回归法。 相似文献
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V. P. Lezina N. A. Andronova L. D. Smirnov K. M. Dyumaev 《Chemistry of Heterocyclic Compounds》1971,7(11):1438-1440
The dependence of the chemical shifts of the ring protons on the pH of the medium for a number of 4-hydroxyquinoline derivatives was studied by means of PMR spectroscopy. The dipolar and uncharged hydroxy forms exist in equilibrium in aqueous solutions. The effect of intramolecular hydrogen bonding on the character of the dependence of the chemical shift on the pH of the medium in the case of 3-piperidinomethyl-4-hydroxyisoquinoline was investigated. The possibility of the separate protonation of the ring nitrogen and the side-chain nitrogen in 3-piperidinomethyl-4-hydroxyisoquinoline was established. The distribution of the -electron density in 4-hydroxyisoquinoline is in good agreement with its chemical behavior.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1546–1549, November, 1971 相似文献
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V. P. Lezina N. A. Andronova L. D. Smirnov K. M. Dyumaev 《Chemistry of Heterocyclic Compounds》1971,7(11):1433-1437
The dependence of the chemical shift of the ring protons on the pH of the medium for a number of 3-hydroxyquinoline derivatives was studied by PMR spectroscopy. The regions of ionization of the molecules, which correspond to the ranges of acidic, neutral, and alkaline media, were found. In D2O, 3-hydroxyquinoline is present only in the uncharged hydroxy form. The presence of intramolecular hydrogen bonding in 4-dimethylaminomethyl-3-hydroxyquinoline has a substantial effect on the character of the dependence of the chemical shift on the pH of the medium; the existence of separate protonation of the nitrogen atoms of the ring and the side chain of 4-dimethylaminomethyl-3-hydroxyquinoline was established. The distribution of the -electron density in the 3-hydroxyquinoline molecule is in good agreement with its chemical behavior during electrophilic substitution.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1540–1545, November, 1971. 相似文献
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通过在LS55型荧光-磷光-发光分光光度计上加装液滴产生及调节附件,采用计算机采集与分析处理数据,成功地研制了双通道液滴光化学传感装置.利用葡聚糖凝胶对复合维生素B中不同组分的选择性吸附来达到分离与同时检测的目的,并将其用于复合维生素B药片的分析,取得了满意的结果. 相似文献
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Tangney P 《The Journal of chemical physics》2006,124(4):044111
The theory underlying the Car-Parrinello extended-Lagrangian approach to ab initio molecular dynamics (CPMD) is reviewed and reexamined using "heavy" ice as a test system. It is emphasized that the adiabatic decoupling in CPMD is not a decoupling of electronic orbitals from the ions but only a decoupling of a subset of the orbital vibrational modes from the rest of the necessarily coupled system of orbitals and ions. Recent work [J. Chem. Phys. 116, 14 (2002)] has pointed out that, due to the orbital-ion coupling that remains once adiabatic decoupling has been achieved, a large value of the fictitious mass mu can lead to systematic errors in the computed forces in CPMD. These errors are further investigated in the present work with a focus on those parts of these errors that are not corrected simply by rescaling the masses of the ions. It is suggested that any comparison of the efficiencies of Born-Oppenheimer molecular dynamics (BOMD) and CPMD should be performed at a similar level of accuracy. If accuracy is judged according to the average magnitude of the systematic errors in the computed forces, the efficiency of BOMD compares more favorably to that of CPMD than previous comparisons have suggested. 相似文献
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Emma Hocker 《Macromolecular Symposia》2006,238(1):16-21
Sweden's famous warship, Vasa, sank on her maiden voyage in August 1628, and remained on the bottom of Stockholm harbour for 333 years. Raised in 1961, she became the first large-scale wooden object to be treated with polyethylene glycol (PEG). In the summer of 2000 a number of acidic salt precipitations were noticed on the surface of the ship and on wooden artefacts in the storerooms. An international research project has been established to look into the causes of this problem and suggest possible re-treatments. Meanwhile projects are underway to monitor movements in the ship, to build a better support system, and to replace the thousands of iron bolts holding the structure together, while a sophisticated new climate system has recently been installed in the museum. 相似文献