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On the basis of financial HJM model and Monte Carlo method and by use of powerful data analysis ability of Microsoft Excel,historical data of gas concentration was analyzed and then a practical rule of gas overflow was gotten,so as to realize prediction of coal mine gas overflow.With gasdetected equipments,the method of predicting gas concentration can effectively reduce rate of accidents,and has certain extersion and application value.

The fused nitrogen‐rich heterocycles, particularly planar structures, possess many advantages over conventional single‐ring energetic compounds. The planar π‐π stacked structures result in enhanced safety. Meanwhile, their conjugated systems give rise to good energetic properties. This review focused on the syntheses, properties, and potential applications of energetic materials based on the coplanar fused nitrogen‐rich heterocycles. Most of these compounds exhibit excellent detonation characteristics along with low mechanical sensitivity which makes them very promising candidates for highly energetic materials for civilian or military applications. [ABSTRACT FROM AUTHOR]

Density functional theory methods were used to study on 2 N10 compounds, 1,1′-azobis(tetrazole) and 1,1′-azobis(5-methyltetrazole). We systematically investigated 10 novel substituted azobis(tetrazoles) with 10 catenated nitrogen atoms and various energetic groups (-CF3 1, -C(NO2)3 3, -N3 5, -NH2 6, -NHNH2 7, -NHNO2 8, -NO2 9, -OCH3 10, -OH 11, -ONO2 12). The optimized geometry, frontier molecular orbitals, electrostatic potential, Infrared and nuclear magnetic resonance spectrum were calculated for inspecting the molecular structure and stability as well as chemical reactivity. The effects of different substituents on the density, enthalpy of formation, heat of explosion, detonation velocity and pressure, and sensitivity of the azobis(tetrazole) derivatives have been investigated. Compound 9 with nitro was found to have remarkable detonation performances ( D = 9.61 km/s, P = 42.14 GPa), which are close to the excellent explosive CL-20. Results show that compounds 1, 3, 4, 7, 9, 11, and 12 have high potential to replace RDX. It is surprising that compounds 1, 3, 9, and 12 possess better energetic properties than HMX. These novel substituted azobis(tetrazoles) with unique N10 structure may be promising candidates of HEDMs with outstanding performance and acceptable sensitivities. [ABSTRACT FROM AUTHOR]

A series of amino-triazolium salts based on 4,5-dicyano-1,2,3-triazolate (C4N5-) anion were synthesized for first time by means of facile deprotonation reactions. The ionic compounds were characterized by single-crystal X-ray diffraction, vibrational spectroscopy, and elemental analysis. The thermal stability of the salts was assessed by differential scanning calorimetry, which showed good thermal stabilities up to above 180 °C. The heats of formation of these salts were computed using the methods of isodesmic reactions. In addition, the sensitivities of the studied salts toward impact and friction were determined, and all salts were found to be neither impact (> 40 J) nor friction sensitive (>360 N). [ABSTRACT FROM AUTHOR]

Energetic mono- and dicationic 3,4-diaminotriazolium salts have been prepared by combining stoichiometric amounts (1:1 or 2:1 molar ratio) of 3,4-diaminotriazole with various oxygen-containing tetrazoles, and the structures have been confirmed by single-crystal XRD for the first time. All structures are dominated by a strong hydrogen-bond network owing to both amino groups and oxygen in the molecule. All salts, except 7, exhibit excellent thermal stabilities with decomposition temperatures over 200 °C. Based on experimental densities and theoretical calculations carried out by using the Gaussian 03 suite of programs, all salts have calculated detonation pressures (20.3-33.9 GPa) and velocities (7095-8642 m s−1). [ABSTRACT FROM AUTHOR]

Objective: To observe the effect of acupuncture therapy based on "gut-brain axis" on clinical manifestations and gastrointestinal symptoms of children with autism spectrum disorder (ASD)., Methods: A total of 66 children with ASD were randomly divided into an observation group and a control group, 33 cases in each group. The control group was treated by routine rehabilitation training. On the basis of the control group, the observation group was treated with acupuncture based on "gut-brain axis", and the acupoints were Touwei (ST 8), Shenting (GV 24), Sishencong (EX-HN 1), Tianshu (ST 25), Zhongwan (CV 12), Zusanli (ST 36), etc. Both treatments were given once every other day, 3 times a week, 4 weeks as a course of treatment, consecutively for 3 courses. The scores of autism behavior checklist (ABC), TCM symptoms of gastrointestinal disease and childhood autism rating scale (CARS) were compared between the two groups before and after treatment, and the clinical efficacy was evaluated., Results: After treatment, the scores of ABC, CARS and TCM symptoms of gastrointestinal disease in the two groups were lower than before treatment ( P <0.05), and those in the observation group were lower than the control group ( P <0.05). The total effective rate of the observation group was 90.9% (30/33), which was higher than 81.8% (27/33) in the control group ( P <0.05)., Conclusion: On the basis of routine rehabilitation training, acupuncture therapy based on "gut-brain axis" is effective in treating ASD, which can relieve the clinical manifestations and gastrointestinal symptoms.

Objective: To explore infection rate of different adeno-associated virus (AAV) on knee joint cartilage in mice and to find a good gene editing tool for mice chondrocytes of knee joint., Methods: Forty-five 4-week-old SPF C57BL/6 weighed(14.3±0.2) g were selected. According to different injections(6 μl) for right knee joint, mice were divided into 9 different groups, 5 mice in each group. The groups were such as following:control group (normal saline), Vigene 2 group (AAV2 from vigene biosciences, titer for 1×10¹³ vg/ml), Vigene 5 group (AAV5 from vigene biosciences, titer for 1×10¹³ vg/ml), Vigene 6 group (AAV6 from vigene biosciences, titer for 1×10¹³ vg/ml), Vigene 7 group (AAV7 from vigene biosciences, titer for 1×10¹³ vg/ml), Vigene 8 group (AAV8 from vigene biosciences, titer for 1×10¹³ vg/ml), Vigene 9 group (AAV9 from vigene biosciences, titer for 1×10¹³ vg/ml), Hanbio DJ group(AAV2-DJ from Hanbio, titer for 1×10¹² vg/ml), Hanbio 5 group (AAV5 from Hanbio, titer for 1×10¹² vg/ml). All AAVs were over-expressed green fluorescent protein(GFP). Knee joint specimens were taken and observed injury of cartilage under stereomicroscope at 30 days after injection, then 10 μm thick frozen sections were prepared. Distribution of green fluorescent protein of meniscus and cartilage of knee joint was observed under fluorescence microscope., Results: Stereomicroscope observation indicated that no obvious lesion was observed in knee joint cartilage of mice after intra-articular injection of AAV. According to frozen sections of knee joints, strong green fluorescence was observed in knee joint cartilage in all AAV experimental groups. Compared with other groups, significantly stronger green fluorescence were observed both in AAV2 and AAV7 groups, whose average fluorescence density was 0.077±0.020 and 0.061±0.022. There were significant differences between two groups and other groups., Conclusions: AAV could infect chondrocyte of knee joint in vivo by injecting into knee joint cavity. Higher infection efficiency of AAV2 and AAV7 on knee joint cartilage were observed. Local injection of AAV into knee joint cavity could be used as an effective tool for gene editing of knee joint chondrocyte., Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose., (Copyright© 2019 by the China Journal of Orthopaedics and Traumatology Press.)

Energetic materials (explosives, propellants, and pyrotechnics) are used extensively for both civilian and military applications and the development of such materials, particularly in the case of energetic salts, is subject to continuous research efforts all over the world. This Review concerns recent advances in the syntheses, properties, and potential applications of ionic salts based on tetrazole N-oxide. Most of these salts exhibit excellent characteristics and can be classified as a new family of highly energetic materials with increased density and performance, alongside decreased mechanical sensitivity. Additionally, novel tetrazole N-oxide salts are proposed based on a diverse array of functional groups and ions pairs, which may be promising candidates for new energetic materials., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)