高等学校化学における「学び」の過程に関する理論的検討 : 理科教師が行う教材化や教材開発の視座を中心として

本稿は，専門領域の研究論文を専門科学者の「学び」の過程に読み替え，さらに学習者の「学び」の過程に再構成することを通して，理科教師が教材化や教材開発を行う視座に関する示唆を得ることを目的とした。Journal of Organometallic Chemistry 誌に掲載された論文を構造的に読解し，執筆者に対する論文（研究）の作成過程に関するインタビュー調査結果を基に，専門科学者の「学び」の過程への読み替えを行い，教材化や教材開発を行う上で求められる視座について分析・検討を行った。その結果，専門科学（研究）者の「学び」の過程とは，専門科学者が数多くの実験を試行する中で新しい発見や次に繋がる研究テーマを見いだしていく研究スタイル（学習過程）であり，経験したことを基に試行錯誤や条件制御をしながら，実験プランや次の研究テーマを考えていくことになるという発見的な実験を主流としたものであった。この専門科学者の「学び」の過程を，理科教師が行う教材化や教材開発の文脈に置き換えた場合，高等学校化学の実験は，どちらかといえば，与えられた実験で結果は決まっているが，とはいえ，実験を行う本人としては初めての体験である。従って，そこには多かれ少なかれ，実験を行った本人にとって何かしらの新しい発見があり，予想外のことが起きる要素はあるという視点が重要である。また，本研究により，理科教師が「科学者による知的生産の知 (scholarly knowledge)」の創成プロセスとその転置メカニズムについて知ることも，教材研究を行う上では重要な位置付けとなることが見出された。The current study aimed to attain implications for teaching material development by a science teacher, through a reframing of a specialized research paper into a “learning” process of a specialized scientist, followed by a further reconstruction into a learner’s “learning” process. We analyzed and investigated the perspectives necessary for teaching material development, through understanding the structure of a paper published in the Journal of Organometallic Chemistry, as well as interviewing with the author of the paper regarding the paper writing process. The result indicated that the process of learning of this specialized scientist was characterized by finding a research topic that led to new discoveries through conducting numerous experiments. The results indicated that the scientist focused on heuristic experiments from which he developed experiment plans and the next research topic by trial-and-error and condition control. If we were to place this “learning” process in the context of teaching material development of a science teacher, it is important to have a point of view that something new would be discovered by a student and something unexpected might occur. Although experiments in high school chemistry usually have prescribed results, experiments are new for the students. In addition, the current study elucidated the importance of a science teacher’s understanding of the creation process of “scholarly knowledge by a scientist” and its mechanism of transposition in his or her teaching material studies

On the Magnetic Susceptibilities of Troponoid System. II : Diamagnetism of Methyl Ether Derivatives

The magnetic susceptibiilties of tropolone methyl ether (Ia), 2-methoxy-7-bromo-tropone (o-bromo-tropolone methyl ether) (II) and α-thujaplicin methyl ether(III) have been measured by use of the Gouy balance described in the previous article.^ The experimental results (-χ_M×10^6) obtained for (Ia), (II) and (III) are 71, 88 and 105 respectively. The susceptibility of crystalline form of (Ia), i. e., (C_8H_8O_2)_2H_2O (Ib), has been also measured, the result being - 160 ×10^ per mole. It has been shown that the value of ΔK_M, which shows the diamagnetic anisotropy of the tropolone ring belonging to each compound, can be easily derived approximately from the experimental value by the application of the empirical additive rule. The remarkable diamagnetic decrements have been observed in the ΔK_M values, the amounts of which depend upon the kinds of the substituents, i. e., OCH_3, Br and isopropyl groups. The results have shown that the ΔK_M value of (II) is almost zero and that of (Ia) is half the value of tropolone itself

On the Magnetic Susceptibilities of Troponoid-System. I : Diamagnetism of Hinokitiol (β-Thujaplicin) and α-Thujaplicin

The diamagnetic susceptibilities of hinokitiol ((β-thujaplicin) and α-thujaplicin in powdered crystal form have been measured and the structures of the tropolone-ring are discussed. The observed molar susceptibilities obtained in the present experiments are -(102±1)×10 for hinokitiol, -(100±3)×10 for α-thujaplicin (colourless, m. p. 34°), and -(97±2)×10 for α-thujaplicin (light yellow, m. p. 24°). These observed data have been compared with calculated values, which were computed by use of the four methods ; the Pascal\u27s additive law, the Slater-Angus method, Langevin\u27s formula referring to the diamagnetism for the planar orbit, and the theory of diamagnetic anisotropy of molecular orbitals (London\u27s method), with the result that there are six π-electrons, within each tropolone-ring of these compounds, which are able to revolve along the closed circuit constructed out of the periphery of seven membered ring. As a necessary consequence of this condition, it follows the ionization between one of the carbon atoms in the ring system and the oxygen atom in the carbonyl group, assuming the former a positive charge and the later a negative one

Synthesis of donor–acceptor chromophores by the [2 + 2] cycloaddition of arylethynyl-2H-cyclohepta[b]furan-2-ones with 7,7,8,8-tetracyanoquinodimethane

Arylethynyl-2H-cyclohepta[b]furan-2-ones reacted with 7,7,8,8-tetracyanoquinodimethane (TCNQ) in a formal [2 + 2] cycloaddition reaction, followed by ring opening of the initially formed cyclobutene derivatives, to afford the corresponding dicyanoquinodimethane (DCNQ) chromophores in excellent yields. The intramolecular charge-transfer (ICT) interactions between the 2H-cyclohepta[b]furan-2-one ring and DCNQ acceptor moiety were investigated by UV/Vis spectroscopy and theoretical calculations. The redox behavior of the novel DCNQ derivatives was examined by cyclic voltammetry (CV) and differential pulse voltammetry (DPV), which revealed their multistep electrochemical reduction properties depended on the number of DCNQ units in the molecule. Moreover, a significant color change was observed by visible spectroscopy under electrochemical reduction conditions.ArticleORGANIC & BIOMOLECULAR CHEMISTRY. 10(12):2431-2438 (2012)journal articl

Photochemical reactions of diazoazulenequinone in aprotic solvents

[[notice]]補正完畢[[conferencetype]]國內[[conferencedate]]19960406~19960406[[conferencelocation]]Japan, Senda