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Phase change materials (PCMs), widely used in thermal management filed, can store or release thermal energy during phase-changing processes, but the inherent low thermal conductivity and leakage problem restrict their practical applications. Herein, boron nitride nanosheets (BNNSs) doped cellulosic scaffolds (CS) were used as novel support materials to construct shape-stabilized PCM with enhanced thermal conductivity. The composite PCM exhibits excellent shape stability against pressure, tension and bending (90°) even at high loading of the solid-liquid PCM polyethylene glycol (PEG) (95.6 wt%). The resulting composite PCMs have enthalpy capacity (ΔHm/ΔHc) ranged from 165.3 J g−1/169.3 J g−1 to 169.1 J g−1/176.1 J g−1 with stable cycling reliability. Moreover, the thermal conductivity of the composite PCM could increase by 42.8% at a low loading of BNNSs (1.9 wt%), without affecting its electrical insulation properties (over 107 Ω cm). The thermally-conductive shape-stabilized PCM composite prepared by this feasible method have great potential in thermal management of electronics.

The thermal decomposition behaviors of 1,3-di (azido-acetoxy)-2-methyl-2-nitropropane (DAMNP) under pressures of 0.1 MPa and 3.0 MPa were investigated by DSC techniques. The results showed that with the increase in pressure, the decomposition heat increased significantly, while the peak temperature increased slightly. The kinetic and thermodynamic parameters of exothermic decomposition reaction were obtained, and the iso-kinetic point was found as 192.0 °C. Using the thermal decomposition parameters, the self-accelerating decomposition temperature and the critical temperature of thermal explosion were calculated to be 190.10 °C and 202.58 °C, respectively. The specific heat capacity of DAMNP was studied with micro-DSC method, and the molar heat capacity was found to be 531.98 J mol−1 K−1. The adiabatic time-to-explosion was calculated to be 75.67 s. The combustion heat of DAMNP was determined with an oxygen bomb calorimeter, and the standard molar enthalpy of formation was calculated to be − 189.46 kJ mol−1. These results are important in evaluating the thermal stability and application prospects of DAMNP.

Microencapsulated phase change materials (microPCMs) of core–shell structure with high payload were fabricated via Pickering emulsion stabilized by regenerated nanochitin (RCh) and its subsequent interfacial polymerization with isocyanate. Size and shell thickness of the microPCMs were tunable by varying concentration of RCh and isocyanate. Due to the super-efficient Pickering stabilizing property of RCh, microPCMs with payload as high as 91.3% and phase-transition enthalpy of 230 J/g were obtained, which demonstrated high thermal durability in retaining 99.5% of their phase-transition enthalpy after 100 heating and cooling scans. Silicone rubber (SR)/microPCMs sheets were further prepared and shown to effectively delay temperature rise in a mobile phone caused by transient surges in processor usage.

The excellent comprehensive properties of Al-La binary alloy are mainly due to the stable distribution of Al-La intermetallic compounds in the microstructure. In this work, first-principle calculations have been performed to investigate the phase stability, elastic and electronic properties of eight binary Al-La intermetallic compounds. The results indicated that crystal parameters of Al-La compounds agree well with other experimental and calculated values. The calculated formation enthalpy and cohesion energies of these compounds are less than zero, which indicates that these Al-La binary compounds have good thermal stability. The result reveals that the cohesive energy of these Al-La intermetallic compounds in the binary system decreases with the increase of La content. Among these compounds, Al3La has the highest shear modulus and the strongest resistance to shear strain. The result indicates that the Al-La compounds in this study have an intrinsic sixth power correlation with the work function. It is found that Al11La3 is the most anisotropic in these Al-La binary compounds. The value at the Fermi level is not equal to zero, indicating that all these binary compounds have metal properties. Debye temperature calculation results show that Al3La has the strongest binding force between atoms of Al-La intermetallic compounds. Furthermore, the results show that these compounds have anisotropy of longitudinal and transverse sound velocity in different crystallographic directions.

Microencapsulated phase change composite materials (MPCMs) with cellulose nanocrystals-composited poly (methyl methacrylate) (PMMA) as shell and n-eicosane as core was facially prepared via Pickering emulsion assisted solvent evaporation approach. PMMA and n-eicosane were dissolved in chloroform as the oil phase. Cellulose nanocrystals (CNC) can efficiently stabilize oil - in - water (O / W) emulsion, and the core-shell ratio will affect the thermal properties of MPCMs, study found that the optimal core-shell ratio was 1:2 and encapsulation ratio reached 58.2 %. The PMMA encapsulated MPCMs displayed a regular spherical shape sized in the range of 5–10 micrometers. They had favorable thermal stability and melting enthalpy of up to 150.8 J/g. Results of the thermal cycling tests showed melting enthalpy of MPCMs were maintained by over 99 % after 100 heating-cooling cycles. The proposed Pickering emulsion assisted solvent evaporation approach provides a potential way for industrial production of microencapsulated phase change materials.

Study on the binding properties of helicid by pepsin systematically using multi-spectroscopic techniques and molecular docking method, and these interactions comprise biological recognition at molecular level and backbone of biological significance in medicine concerned with the uses, effects, and modes of action of drugs. We investigated the mechanism of interaction between helicid and pepsin by using various spectroscopic techniques viz., fluorescence spectra, UV–Vis absorption spectra, circular dichroism (CD), 3D spectra, synchronous fluorescence spectra and molecular docking methods. The quenching mechanism associated with the helicid–pepsin interaction was determined by performing fluorescence measurements at different temperatures. From the experimental results show that helicid quenched the fluorescence intensity of pepsin via a combination of static and dynamic quenching process. The binding constants (Ka) at three temperatures (288, 298, and 308 K) were 7.940 × 107, 2.082 × 105 and 3.199 × 105 L mol−1, respectively, and the number of binding sites (n) were 1.44, 1.14, and 1.18, respectively. The n value is close to unity, which means that there is only one independent class of binding site on pepsin for helicid. Thermodynamic parameters at 298 K were calculated as follows: ΔHo (− 83.85 kJ mol−1), ΔGo (− 33.279 kJ mol−1), and ΔSo (− 169.72 J K−1 mol−1). Based on thermodynamic analysis, the interaction of helicid with pepsin is driven by enthalpy, and Van der Waals’ forces and hydrogen bonds are the main forces between helicid and pepsin. A molecular docking study further confirmed the binding mode obtained by the experimental studies. The conformational changes in the structure of pepsin was confirmed by 3D fluorescence spectra and circular dichroism.

The enthalpies of dissolution of dihydrazidinium bis(tetrazolyl)amine (DHBTA) in water and N-methyl pyrrolidone (NMP) were measured using a RD496-2000 Calvet microcalorimeter at 298.15 K under atmospheric pressure, respectively. Empirical formulae for the calculation of the enthalpy of dissolution (Δdiss H), relative partial molar enthalpy (Δdiss H partial) and relative apparent molar enthalpy (Δdiss H apparent) were obtained from the experimental data of the dissolution processes of DHBTA in water and NMP. Furthermore, the corresponding kinetic equations describing the two dissolution processes were dα/dt = 10−2.70(1 − α)0.82 for the dissolution of DHBTA in water, and dα/dt = 10−2.47(1 − α)0.66 for the dissolution of DHBTA in NMP, respectively.

The enthalpy of dissolution of NNHT in N,N-dimethyl formamide (DMF) was measured by means of a DC08 Calvet microcalorimeter at 298.15 K. Empirical formulae for the calculation of the enthalpy of dissolution (ΔdissH), relative partial molar enthalpy (ΔdissHpartial), and relative apparent molar enthalpy (ΔdissHapparent) were obtained from the experimental data of the enthalpies of dissolution of NNHT in DMF. The kinetic equation that describes the dissolution process of NNHT in DMF at 298.15 K is determined as \( \frac{{{{\rm d}}\alpha }}{{{{\rm d}}t}} = 2.86 \times 10^{ - 3} (1 - \alpha )^{0.94} \).

Three high-energy salts (3, 4 and 5) based on oxy-bridged bis(gem-dinitro) furazan with potassium and nitrogen-rich cations were reported. Their structures were fully characterized and confirmed by NMR (1H, 13C), IR spectroscopy, elemental analysis and single crystal X-ray diffraction. The thermal decomposition behaviors were studied by DSC and TG methods. And, the decomposition process of 5 was studied by the thermolysis in-situ rapid-scan FTIR. The non-isothermal kinetics parameters were obtained by Kissinger’s and Ozawa’s methods, respectively. The activation entropy (ΔS≠), activation enthalpy (ΔH≠), activation Gibbs free energy (ΔG≠) and the critical temperature of thermal explosion were calculated.

Two propionic acid ionic liquids (PrAILs) [C n mim][Pro] ( n = 2, 3) (1-alkyl-3-methylimidazolium propionate) were prepared by the neutralisation method and characterised by 1 H NMR spectroscopy and differential scanning calorimetry (DSC). The values of vaporisation enthalpies, Δ vap H m o , for two PrAILs [C n mim][Pro] ( n = 2, 3) were determined using a simple, convenient, and highly reproducible thermogravimetric approach. The enthalpy of vaporisation, Δ vap H m o , for ionic liquids (ILs) is assumed to be composed of two parts: one part corresponds with the induced energy, Δ vap H m o ( n ) , and the other part corresponds with orientation energy from permanent dipole moment of ion pair in ILs, Δ vap H m o ( μ ) . Using the values of Δ vap H m o , Δ vap H m o ( n ) and Δ vap H m o ( μ ) , cohesive energy density, δ 2 ( δ is the solubility parameter), the contribution of inducted energy, δ n 2 , and the contribution of orientation energy, δ μ 2 , were obtained. If a liquid only has δ n then it is a non-polar liquid, and if a liquid not only has δ n also has δ μ then it is a polar liquid. Since the ion pairs in ILs have permanent dipole moment, ionic liquid has a certain polarity. Therefore, using δ μ as the polarity scaling of ILs is very convenient because the values of δ μ are very easy to calculate from the enthalpy of vaporisation and refractive index data.

1,3-Bis(4-aminophenoxy)benzene (TPER) and poly(amic acid) based on TPER and pyromellitic dianhydride (PMDA) were synthesized. After imidization of the poly(amic acid), polyimide based on TPER and PMDA was obtained. The melting process and the specific heat capacity (C p) of TPER were examined by DSC and microcalorimetry, respectively. The melting enthalpy, the melting entropy, and the C p for TPER were obtained. The enthalpy change, the entropy change, and the Gibbs free energy change for TPER were obtained within 283 and 353 K. The thermal decomposition reaction mechanism of the polyimide is classified from the TG–DTG experimental data, and the thermokinetic parameters of the thermal decomposition reaction are E a = 296.87 kJ mol−1and log (A/s−1) = 14.41.

The properties of dissolution in different solvents, the specific heat capacity and thermal decomposition process under the non-isothermal conditions for energetic triazole ionic salts 1,2,4-triazolium nitrate (1a), 1,2,3-triazolium nitrate (1b), 3,4,5-triamino-1,2,4-triazolium nitrate (2a), 3,4,5-triamino-1,2,4-triazolium dinitramide (2b) were precisely measured using a Calvet Microcalorimeter. The thermochemical equation, differential enthalpies of dissolution (Δdif H m Θ ), standard molar enthalpies of dissolution (Δdif H m Θ ), apparent activation energy (E), pre-exponential constant (A), kinetic equation, linear relationship of specific heat capacity with temperature over the temperature range from 283 to 353 K, standard molar heat capacity (C p,m Θ ) and enthalpy, entropy and Gibbs free energy at 283–353 K, taking 298.15 K as the benchmark for 1a, 1b, 2a and 2b were obtained with treating experimental data and theoretical calculation method. The kinetic and thermodynamic parameters of thermal decomposition reaction, critical temperature of thermal explosion (T b), self-accelerating decomposition temperature (T SADT) and adiabatic time-to-explosion (t) of 1a, 1b, 2a and 2b were calculated. Their heat-resistance abilities were evaluated. Information was obtained on the relation between molecular structures and properties of 1a, 1b, 2a and 2b.

The thermal decomposition behaviors of 1,2,3-triazole nitrate were studied using a Calvet Microcalorimeter at four different heating rates. Its apparent activation energy and pre-exponential factor of exothermic decomposition reaction are 133.77 kJ mol−1 and 1014.58 s−1, respectively. The critical temperature of thermal explosion is 374.97 K. The entropy of activation (ΔS≠), the enthalpy of activation (ΔH≠), and the free energy of activation (ΔG≠) of the decomposition reaction are 23.88 J mol−1 K−1, 130.62 kJ mol−1, and 121.55 kJ mol−1, respectively. The self-accelerating decomposition temperature (TSADT) is 368.65 K. The specific heat capacity was determined by a Micro-DSC method and a theoretical calculation method. Specific heat capacity equation is \( C_{\text{p}} \left( {{\text{J mol}}^{ - 1} {\text{ K}}^{ - 1} } \right) = - 42.6218 + 0.6807T \) (283.1 K < T < 353.2 K). The adiabatic time-to-explosion is calculated to be a certain value between 98.82 and 100.00 s. The critical temperature of hot-spot initiation is 637.14 K, and the characteristic drop height of impact sensitivity (H50) is 9.16 cm.

The thermal decomposition behaviors of 3,4,5-triamino-1,2,4-triazole nitrate were studied using a C-500 type Calvet Micro-calorimeter at four different heating rates. Its apparent activation energy and pre-exponential factor of exothermic decomposition reaction are 137.16 kJ mol−1 and 1010.03 s−1. The critical temperature of thermal explosion is 441.37 K. The entropy of activation (ΔS≠), enthalpy of activation (ΔH≠), and free energy of activation (ΔG≠) of the decomposition reaction are −65.65 J mol−1 K−1, 132.97 kJ mol−1 and 166.35 kJ mol−1, respectively. The self-accelerating decomposition temperature (TSADT) is 429.56 K. The specific heat capacity was determined with a Micro-DSC method and a theoretical calculation method. Specific heat capacity (J g−1 K−1) equation is Cp = 0.356 + 2.957 × 10−3T (283.1 K

The thermal decomposition behavior of 3,4,5-triamino-1,2,4-triazole dinitramide was measured using a C-500 type Calvet microcalorimeter at four different temperatures under atmospheric pressure. The apparent activation energy and pre-exponential factor of the exothermic decomposition reaction are 165.57 kJ mol−1 and 1018.04s−1, respectively. The critical temperature of thermal explosion is 431.71 K. The entropy of activation (ΔS≠), enthalpy of activation (ΔH≠), and free energy of activation (ΔG≠) are 97.19 J mol−1K−1, 161.90 kJ mol−1, and 118.98 kJ mol−1, respectively. The self-accelerating decomposition temperature (TSADT) is 422.28 K. The specific heat capacity of 3,4,5-triamino-1,2,4-triazole dinitramide was determined with a micro-DSC method and a theoretical calculation method. Specific heat capacity (J g−1K−1) equation is Cp = 0.252 + 3.131 × 10−3T (283.1 K < T < 353.2 K). The molar heat capacity of 3,4,5-triamino-1,2,4-triazole dinitramide is 264.52 J mol−1 K−1 at 298.15 K. The adiabatic t...

The enthalpies of dissolution in ethyl acetate and acetone of hexanitrohexaazaisowurtzitane (CL-20) were measured by means of a RD496-2000 Calvet microcalorimeter at 298.15 K, respectively. Empirical formulae for the calculation of the enthalpy of dissolution (ΔdissH), relative partial molar enthalpy (ΔdissHpartial), relative apparent molar enthalpy (ΔdissHapparent), and the enthalpy of dilution (ΔdilH1,2) of each process were obtained from the experimental data of the enthalpy of dissolution of CL-20. The corresponding kinetic equations describing the two dissolution processes were \( {\frac{{{\text{d}}\alpha }}{{{\text{d}}t}}} = 1.60 \times 10^{ - 2} (1 - \alpha )^{0.84} \) for dissolution process of CL-20 in ethyl acetate, and \( {\frac{{{\text{d}}\alpha }}{{{\text{d}}t}}} = 2.15 \times 10^{ - 2} (1 - \alpha )^{0.89} \) for dissolution process of CL-20 in acetone.

The thermal behavior and decomposition reaction kinetics of 2-nitroimino-5-nitro-hexahydro-1,3,5-triazine (NNHT) were investigated by TG–DTG and DSC under atmospheric pressure and flowing nitrogen gas conditions. The results show that the thermal decomposition process of NNHT has two mass loss stages. The exothermic decomposition reaction mechanism obeys chemical reaction rule. The kinetic parameters of the reaction are Ea = 131.77 kJ mol−1, lg(A/s−1) = 12.56, respectively. The kinetic equation can be expressed as: d α / d t = 10 12.86 1 − α 3 / 2 e − 1.5849 × 10 4 / T . The critical temperature of thermal explosion of NNHT obtained from the peak temperature (Tp) is Tbp = 467.22 K. The entropy of activation (ΔS≠), enthalpy of activation (ΔH≠), and free energy of activation (ΔG≠) of the reaction are −7.978 J mol−1 K−1, 127.99 kJ mol−1 and 131.62 kJ mol−1, respectively.

The enthalpy of dissolution of 1,1-diamino-2,2-dinitroethylene (FOX-7) in DMSO was measured by means of a RD496-2000 Calvet microcalorimeter at 298.15 K. Empirical formulae for the calculation of the enthalpy of dissolution (ΔdissH), relative partial molar enthalpy (ΔdissHpartial) and relative apparent molar enthalpy (ΔdissHapparent) were obtained from the experimental data of the enthalpies of dissolution of FOX-7 in dimethyl sulfoxide (DMSO). The dilution/crystallization kinetic behavior of FOX-7 in DMSO/water system was investigated and the kinetic equation describing the dilution/crystallization process was presented.