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Gold nanorods are of great significance in biomedical and sensing applications due to their local surface plasmon resonance absorption. The silver-mediated seeding method was used to prepare gold nanorods, the longitudinal local surface plasmon resonance (LSPR) absorption of the prepared gold nanorods was monitored, and the growth kinetics of the gold nanorods were discussed. The results show that the growth process of gold nanorods is characterized by a first-order reaction, and its activation energy is about 54.4 kJ/mol. This experimental conclusion provides a good theoretical guide for the preparation of gold nanorods during application research.

Fraxinellone is an important botanical lactone compound and has been demonstrated to have insecticidal activity. To provide theoretical support to the assessment on the safety of utilizing fraxinellone as a natural insecticidal agent, the interactions between fraxinellone and armyworm DNA, salmon sperm DNA and calf thymus DNA were investigated using UV–Vis absorption spectroscopy, isothermal titration calorimetry, and molecular docking. Results showed that there were two types of combinations between fraxinellone and three kinds of DNA. Type I combination had an equilibrium constant of combination (Ka1) of about 105 and binding sites (n1) of 0.40–0.70, while type II combination had an equilibrium constant of combination (Ka2) of 103 and binding sites (n2) of 1.35–3.15. Results of molecular docking showed that there were non-classical embedding type interactions between fraxinellone and three kinds of DNA, with the reaction taking place in small groove areas of the DNA structure, resulting in relatively weak interactive forces.

The dissolution process of penicillin in normal saline and isotonic glucose solution was reported using a microcalorimeter. Both the integral and differential heats of solution were measured. The quantitative relationships between the amount of heat released and the quantity of dissolved penicillin were established. Meanwhile, the kinetics and the half-life of the dissolution processes as well as the enthalpy of solution, the entropy of dissolution, and the free energy of dissolution were determined. The results showed that a change of the solvent from normal saline to isotonic glucose solution had little effect on the half-life of penicillin in the dissolution process, and there was no significant difference between the stabilities of penicillin in isotonic glucose solution and normal saline. Moreover, the dissolution process of penicillin in isotonic glucose solution followed the first-order kinetics. These results could provide a theoretical basis for the clinical applications of penicillin.

Variations of H+, Mn2+, and \({{\rm BrO}_3^-}\) during chemical oscillating reactions involving amino acids were investigated using H2SO4–\({{\rm BrO}_3^{-}}\) –Mn2+–acetone as an oscillator, and the thermodynamic functions (ΔS, ΔH, and ΔG) were calculated. The results indicated that the oscillating reaction is a process from disorder to order. In the oscillating system, the heat provided by the environment is used to increase the internal energy and entropy. When external positive entropy flow could make the system reach negative entropy flow, the system starts to oscillate and to maintain oscillations by a stable entropy.

In this article, the enthalpies of dissolution of resveratrol in dimethyl sulfoxide (DMSO) were measured using a RD496-2000 Calvet microcalorimeter at 298.15 K under atmospheric pressure. The differential enthalpy (Δdif H m) and molar enthalpy (Δsol H m) of dissolution of resveratrol in DMSO were determined, and the relationship between heat and the amount of solute was also established. Based on the thermodynamic and kinetic knowledge, the corresponding kinetic equation, half-life, Δsol H m, Δsol S m, Δsol G m, the relative partial molar enthalpy (Δsol H m(partial)) and the relative apparent molar enthalpy (Δsol H m(app)) of the dissolution process were obtained. The results showed that this study not only provided a simple method for the determination of the half-life for a drug, but also offered a theoretical reference for the clinical application of resveratrol.

Laburnine’s dissolution behaviors in glucose and saline solution were studied by a micro-calorimetry method. The measured integral and differential heats of solution were utilized to build equations of the solute and the heat, so that dissolution thermodynamic equations and half-time periods, Δsol H m, Δsol G m, and Δsol S m were obtained. The results show that this study does not only provide a simple method for the determination of the half-life period for a drug but also offer a theoretical reference for the clinical application of laburnine.

In this paper, the enthalpies of dissolution of matrine in ethanol (EtOH) were measured using a RD496-2000 Calvet microcalorimeter at 309.65 K under atmospheric pressure. The differential enthalpy (Δdif H m) and molar enthalpy (Δsol H m) of dissolution of matrine in ethanol were determined. And the relationship between heat and the amount of solute was also established. Based on the thermodynamic and kinetic knowledge, the corresponding kinetic equation that described the dissolution process was determined to be $${\frac{{\rm d}\alpha}{{\rm d}t}=2.36\times 10^{-4}(1-\alpha )^{1.09}}$$ . Moreover, the half-life, t 1/2 = 48.89 min, Δsol H m = −12.40 kJ · mol−1, Δsol S m = −354.7 J · mol−1 · K−1, and Δ sol G m = 97.43 kJ · mol−1 of the dissolution process were also obtained. The results show that this work not only provides a simple method for the determination of the half-life for a drug but also offers a theoretical reference for the clinical application of matrine.

In this article, the enthalpy of dissolution for oxymatrine in 0.15 M citric acid solution is measured using a RD496-2000 Calvet Microcalorimeter at 36.5 °C under atmospheric pressure. The differential enthalpy (Δ dif H m) and molar enthalpy (Δ sol H m) were determined for oxymatrine dissolution in 0.15 M citric acid solution. On the basis of these experimental data and calculated results, the kinetic equation, half-life, Δ sol H m, Δ sol G m, and Δ sol S m of the dissolution process were also obtained.

Pulsed laser photolysis/laser-induced fluorescence (LP-LIF) is utilized to measure rate constants for C2(a3Πu) reactions with NO, N2O, O2, H2 and NH3. Multiphoton dissociation of C2Cl4 at 266 nm is employed for the generation of C2(a3Πu) radicals. The C2(a3Πu) concentration is monitored by the fluorescence of the (0, 0) band of the (d3Πg↔a3Πu) transition at 516.5 nm. C2(a3Πu) removal rate constants for the reactions are determined as kNO = (5.46 ± 0.10) × 10−11 cm3 molecule−1 s−1, $$\begin{gathered} k_{NO} = (5.46 \pm 0.10) \times 10^{ - 11} cm^3 molecule^{ - 1} s^{ - 1} , \hfill \\ k_{N_2 0} = (1.63 \pm 0.20) \times 10^{ - 13} cm^3 molecule^{ - 1} s^{ - 1} , \hfill \\ k_{N_2 0} = (1.58 \pm 0.16) \times 10^{ - 11} cm^3 molecule^{ - 1} s^{ - 1} , \hfill \\ k_{0_2 } = (5.92 \pm 1.00) \times 10^{ - 14} cm^3 molecule^{ - 1} s^{ - 1} , \hfill \\ k_{H_2 } = < \hfill \\ \end{gathered} $$ .