In this present paper, a new physical parameter (named as thermo‐kinetic parameter) of reactants was defined according to Zhu's kinetic equation, which can be used to quantitatively estimate activation free energy of various chemical reactions. In order to test the actual application of the thermo‐kinetic parameter of reactants, the thermo‐kinetic parameter values of 109 hydrogen atom donors and 109 hydrogen atom acceptors in acetonitrile at 298 K were determined using experimental methods and the rate constants of 5886 hydrogen atom transfer reactions in acetonitrile at 298 K were quantitatively estimated only using the thermo‐kinetic parameter values of the 109 hydrogen atom donors and the 109 hydrogen atom acceptors in acetonitrile at 298 K. The reliabilities of the estimations were verified. Physical meanings and affecting factors of the thermo‐kinetic parameter were elucidated and examined, respectively. The most significant contribution of this paper is to realize the chemists’ dream for a century that the reaction rate constants can be quantitatively estimated using only one physical parameter for each reactant.

In this work, kinetic isotope effect (KIEself) values of 68 hydride self-exchange reactions, XH(D) + X(+) → X(+) + XH(D), in acetonitrile at 298 K were determined using a new experimental method. KIE values of 4556 hydride cross transfer reactions, XH(D) + Y(+) → X(+) + YH(D), in acetonitrile were estimated from the 68 determined KIEself values of hydride self-exchange reactions using a new KIE relation formula derived from Zhu's kinetic equation and the reliability of the estimations was verified using different experimental methods. A new KIE kinetic model to explain and predict KIE values was developed according to Zhu's kinetic model using two different Morse free energy curves instead of one Morse free energy curve in the traditional KIE theories to describe the free energy changes of X-H bond and X-D bond dissociation in chemical reactions. The most significant contribution of this paper to KIE theory is to build a new KIE kinetic model, which can be used to not only uniformly explain the various (normal, enormous and inverse) KIE values but also safely prodict KIE values of various chemical reactions.

) in acetonitrile were examined using experimental method or the available related thermodynamic data for the first time, which can facilitate chemists to choose a suitable reducing agent between Hantzsch ester and H 2 to reduce a given organic unsaturated compound in acetonitrile and make a rational diagnosis on the detailed reaction mechanisms. The focus of this paper is to compare the differences between Hantzsch ester and H 2 to release two hydrogen atoms (or ions) on the thermodynamics of elementary steps in acetonitrile.

Short-term (one hour) application (painting on surfaces of leaves) of 9 muM GA(3) increased net photosynthetic rate (Pn) in broad bean leaves at 31 Pa CO(2) and saturating light by more than 20% compared with that of control. The increased Pn was accompanied by an increase in stomatal conductance and a decrease in intercellular CO(2) partial pressure. Moreover, the GA(3)treatment increased the rate of photosynthetic oxygen evolution in isolated broad bean protoplasts to an extent similar to that of leaves. It had little effect on apparent photosynthetic quantum yield and photosynthetic electron transport rate, but could significantly increase carboxylation efficiency in leaves. In consonance with the increase in the carboxylation efficiency, RuBPCase activity and relative content of Rubisco large subunits were also increased by GA(3) treatment. Chloramphenicol, an inhibitor of chloroplast protein synthesis, could eliminate the enhancing effect of GA(3) on photosynthetic oxygen evolution and relative content of Rubisco large subunits in broad bean protoplasts. Nevertheless, actinomycin D and rifampicin, DNA transcription inhibitors, could not eliminate the enhancement effect of GA(3). Similar results were obtained with soybean leaves treated by 90 muM GA(3). These results suggest that the increase in leaf net photosynthetic rate caused by GA(3) short-term treatment is mainly due to the increases in content and activity of RuBPCase, and that GA(3) stimulates the synthesis of Rubisco subunits at translation rather than transcription level.