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To alleviate the shortage of natural gas supply, the in-situ conversion of coal to natural gas is more beneficial for advancing the clean and efficient use of energy. Since in-situ coal gas contains complex components, such as H2, CH4, and CO, their leakage poses a serious risk to human life and property. Currently, the area of consequence of the harm caused by a leak in a gathering pipeline transporting in-situ coal gas has not been clarified. Therefore, this paper adopted the method of numerical simulation to pre-study the concentration distribution of each component and determined that the main components of concern are CO and H2 components. Afterward, the diffusion law of in-situ coal gas is analyzed and studied under different working conditions, such as wind speed, temperature, pipe diameter, leakage direction, and leakage aperture ratio. The results indicate that when a pipeline leak occurs, the CO component has the largest influence range. With increasing wind speed, the warning boundary of CO rapidly expands downwind, then gradually diminishes, reaching a peak value of 231.62 m at 7 m/s. The range of influence of the leaked gas is inversely proportional to temperature and directly proportional to pipe diameter and leakage aperture ratio. When the gas leaks laterally, the diffusion early warning boundary value of each component is maximal. Among them, the leakage aperture ratio has a significant impact on the concentration distribution of in-situ coal gas, whereas the effect of temperature is relatively minor. This study contributes to an understanding of the leakage and diffusion characteristics of in-situ coal gas-gathering pipelines. [ABSTRACT FROM AUTHOR]

Chemotherapy as a cornerstone of cancer treatment is slowly being edged aside owing to its severe side effects and systemic toxicity. In this case, nanomedicine has emerged as an effective tool to address these drawbacks. Herein, a biocompatible carrier based on bovine serum albumin (BSA) coated gadolinium oxide nanoparticles (Gd2O3@BSA) was fabricated for curcumin (CUR) delivery and its physicochemical features along with its potential anticancer activity against nasal squamous cell carcinoma were also investigated. It was found that the fabricated Gd2O3@BSA containing CUR (Gd2O3@BSA-CUR) had spherical morphology with hydrodynamic size of nearly 26 nm, zeta-potential of -36 mV and high drug (CUR) loading capacity. Drug release profile disclosed that the release of CUR from the prepared Gd2O3@BSA-CUR nanoparticles occurred in a sustained- and pH-dependent manner. Also, in vitro cytotoxicity analysis revealed that the fabricated Gd2O3@BSA nanoparticles possessed excellent biosafety toward HFF2 normal cells, while Gd2O3@BSA-CUR appeared to display the greatest anticancer potential against RPMI 2650 and CNE-1 cancer cell lines. The results also show that the Gd2O3@BSA nanoparticles were compatible with the blood cells with minor hemolytic effect (< 3%). The manufactured NPs were found to be completely safe for biological applications in an in vivo subacute toxicity study. Taken together, these finding substantiate the potential anticancer activity of Gd2O3@BSA-CUR nanoparticles against nasal squamous cell carcinoma, but the results obtained demand further studies to assess their full potential. [ABSTRACT FROM AUTHOR]

In this work, two series of novel high-nitrogen tetrazole 3-N-oxides substituted by different nitrotetrazoles were designed, and their structure and properties were investigated by using the density functional theory (DFT) method. The results shown that though there are only one to two energetic substituents in the structure, because of the high nitrogen content, ideal oxygen balance, and the big conjugated structure, all eight designed compounds not only have high heat of formation (655.4-845.6 kJ/mol), high density (1.83-1.93 [g/cm.sup.3]), and high detonation performance (detonation velocity: 9.06-9.50 km/s; detonation pressure: 36.7-41.8 GPa), but also possess reduced impact sensitivity (23-98 cm). Fully analyzing the energy and sensitivity, A1 and A4 have higher energy and lower sensitivity than one famous high energy compound 1,3,5,7-tetranitro-1,3,5,7-tetrazocane (HMX), and A3, B1, and B4 have comparable overall performance with HMX, showing that these five designed compounds may be considered as the potential high energy density compounds. In addition, the introduction of one extra nitro group into the tetrazole 3-N-oxide could not improve the combination property generally. Key words: tetrazole 3-N-oxide, nitrotetrazole, DFT, high energy density compound. Dans le cadre des présents travaux, nous avons imaginé deux séries de nouveaux tétrazoles 3-N-oxydes à haute teneur en azote comportant différents substituants à base de nitrotétrazoles et nous avons étudié leur structure et leurs propriétés au moyen de calculs en théorie de la fonctionnelle de la densité. Les résultats ont montré que, bien qu'ils ne comportent qu'un ou deux substituants énergétiques dans leur structure, en raison de leur forte teneur en atomes d'azote, de leur bilan d'oxygène idéal et de l'étendue de leur structure conjuguée, les huit composés proposés présentent non seulement une chaleur de formation élevée (655,4-845,6 kJ/mol), une densité élevée (1,83-1,93 [g/cm.sup.3]) et une très bonne performance de détonation (vitesse de détonation : 9,06-9,50 km/s; pression de détonation : 36,7-41,8 GPa), mais possèdent aussi une sensibilité à l'impact réduite (23-98 cm). En procédant à une analyse complète de l'énergie et de la sensibilité, nous constatons que les composés A1 et A4 possèdent une énergie plus élevée et une sensibilité plus faible que l'un des composés hautement énergétiques très connus, le 1,3,5,7-tétranitro-1,3,5,7-tétrazocane (HMX), et que les composés A3, B1 et B4 présentent une performance globale comparable à celle du HMX. Ces résultats montrent que ces cinq composés théoriques pourraient constituer d'éventuels candidats comme composés hautement énergétiques. Par ailleurs, l'incorporation d'un groupe nitro supplémentaire sur le noyau tétrazole 3-N-oxyde ne permettait pas d'améliorer les propriétés combinées dans leur ensemble. [Traduit par la Rédaction] Mots-clés : tétrazole 3-N-oxyde, nitrotétrazole, DFT, composé à haute densité énergétique., Introduction High energy density compounds are one kind of specific but crucial compounds that stockpile huge energy, making them possess high application value for national defense fields such as high [...]

g-C3N4/NiO composites were prepared by a simple mixing-calcination method. The structure and morphology of g-C3N4/NiO were characterized by X-ray Diffraction(XRD), Fourier Transform Infrared Spectrometer(FT-IR), Field Emission Scanning Electron Microscopy(FESEM) and Energy Dispersive X-ray spectroscopy(EDS). The catalytic effect of g-C3N4/NiO on thermal decomposition of ammonium perchlorate(AP) was investigated by Differential Thermal Analysis(DTA) and Thermo Gravimetric Analysis (TG). The results show that nanometer NiO is uniformly dispersed on the surface of g-C3N4, g-C3N4/NiO composites make the two decomposition peaks of AP combine and the high-temperature decomposition peak value of AP decrease by 62.5℃, which exhibits good catalytic performance. The catalytic activity of g-C3N4/NiO is much higher than that of single-phase g-C3N4 and NiO, clearly demonstrating a synergistic effect between g-C3N4 and NiO.