Filtration Combustion of an Energetic Material in a Cocurrent Flow of Its Combustion Products. Critical Combustion Conditions

The paper reports results of a numerical calculation using the threetemperature model developed previously by the authors. In addition to the temperature difference between the gas and the solid phase (skeleton), the model approximately takes into account the temperature distribution in skeleton elements. It is shown that quenching is possible (after burnout of part of the charge) with variation in a number of input parameters: the thermal conductivity of the charge, the ignition temperature, the weight of the igniter, the initial temperature, the porosity of the charge, and the local rate of its decomposition.     

An Overview,Advantages and Therapeutic Potential of Nonpeptide Positive Allosteric Modulators of Glucagon-Like Peptide-1 Receptor

Due to uncomfortable injection regimens of peptidic agonists of glucagon-like peptide-1 receptor (GLP-1R), orally available nonpeptide positive allosteric modulators (PAMs) of GLP-1Rs are foreseen as the possible future mainstream therapy for type 2 diabetes. Herein, current GLP-1R PAMs are reviewed. Based on the effectiveness and in silico predicted physicochemical properties, pharmacokinetics, and toxicity, possible candidates for further development as oral drugs were selected. The suggestion is that GLP-1R PAMs might be used orally alone or in combination with dipeptidyl peptidase-4 (DPP-4) inhibitors, which could offer an optimal treatment option next to metformin monotherapy in type 2 diabetes mellitus, or in a wider spectrum of indications. Quercetin acts as a GLP-1R PAM and DPP-4 inhibitor, and therefore, might be considered as a pioneering agent with a dual mechanism of action, in terms of GLP-1R positive allosteric modulation and DPP-4 inhibition for potentiating GLP-1 dependent effects.     

Initiation of the Decomposition of a Semi-Transparent Mixture of Energetic Materials

In this paper, we propose a model for the heating and decomposition of a binary mixture of energetic materials by a short laser pulse which takes into account melting and the formation of a two-phase zone and the decomposition reaction of the individual components of the mixture. A binary solution of furazanotetrazine-dioxide (C₂N₆O₃) and dinitrazapentane (C₃H₈N₄O₄) was studied as a model system. The pressure change in the reaction zone was calculated, and the effect of pressure on the rate of decomposition reactions was examined. Numerical investigations were performed to study the dynamics of the process and determine the main stages of the process: melting, the propagation of reaction zones in the mixture, the rapid development of an explosion or the termination of reactions, depending on the amount of stored energy. The influence of the optical properties of the mixture on the initiation dynamics was demonstrated.     

Combustion of model compositions based on furazanotetrazine dioxide and dinitrodiazapentane. I. Binary systems

The combustion behavior of high-energy systems based on furazano[3,4-e]tetrazine-4,6-dioxide and 2,4-dinitro-2,4-diazapentane with metal and energetic additives (Al, AlH₃ ammonium perchlorate, ammonium dinitramide, and HMX) has been studied. The burning rate, combustion stability, and characteristic combustion temperatures with pressure variation are estimated. It is found that there is a critical burning rate above which a deflagration-to-explosion transition occurs. The critical conditions depend on the formulation of the compositions.     

The development of corporate social responsibility in the Australian construction industry

In the Australian construction industry, large companies develop corporate social responsibility (CSR) in order to maintain an image of being a good corporate citizen. CSR relevant to the construction industry is defined including the following activities: moral obligation to be a good citizen; sustainability; reputation; relationship with employees and unions; relationship with suppliers and community representatives; and commitment to reporting on CSR. CSR is then examined through 85 interviews conducted with members of boards of directors, suppliers, employees, customers and community representatives of 17 large corporations. In order to be recognized as a socially responsible business, the corporations should: apply a corporate governance structure that takes into consideration working environment concerns; improve their sustainability, occupational health and safety measures, relationships with suppliers and commitment to local community protection and engagement.     

Economic geology value of oil shale deposits: Ethiopia (Tigray) and Jordan

Oil shale is an organic-rich, fine-grained sedimentary rock, containing kerogen, from which liquid hydrocarbons (called shale oil) can be produced. The oil shale deposits in the Tigray region are found in the northern parts of Ethiopia, Eastern Africa. They are of Upper Paleozoic in age, existing as remnants of the Cretaceous erosion period, underlain by tillites and overlain by sandstones. They were formed during the glacial retreat followed by marine deposition of shales in a basin created by the enormous load of the glaciers. The Ethiopian-Tigray oil shale deposits cover an area extending over approximately 30 km², with an average mineable bed-thickness of 55 m, showing on the upper part inter-beds and laminations of shaley limestones. The oil shale resources in this region are estimated to be approximately 4 billion tonnes. The exploitation of the Ethiopian-Tigray oil shale deposits is an excellent alternative to fulfill the fuel and other petroleum products’ demand of Ethiopia. This study sheds light on the oil shale resources in the Ethiopian region of Tigray, as they are fairly investigated, regarding their geological characterization, and future strategies for their exploration and exploitation potential. In addition, the oil shale deposits in Jordan are also moderately investigated, as Jordan is considered a promising country for shale oil, taking into account that Jordan has no other hydrocarbon resources (such as crude oil and natural gas), unlike many other countries in the MENA (Middle East and North Africa) region, as MENA sets on “seas” of oil and natural gas. Furthermore, oil shale in the USA is also briefly investigated, as the USA is being the world’s largest country of oil shale resources and reserves. Also, some other issues related to the oil shale industry are investigated, such as economics, extraction technologies of shale oil, and the environmental impacts.     

Searching for ways to create energetic materials based on polynitrogen compounds (review)

Polynitrogen compounds (containing only nitrogen atoms) are promising candidates as energetic materials for rocket engineering. The high energy content of these compounds is due to the significant difference in bond energy between nitrogen atoms. In particular, molecular nitrogen (N₂) is characterized by a uniquely strong triple bond — 229 kcal/mole, whereas the single-bond energy is only 38.4 kcal/mole. From theoretical estimates, use of polynitrogen compounds can provide a specific impulse of 350–500 sec with material density in a range of 2.0–3.9 g/cm³. This paper gives a brief review of the current status of experimental and theoretical studies in the chemistry of polynitrogen compounds.     

Laser initiation of crystallized mixtures of furazanotetrazine dioxide and dinitrodiazapentane

Experiments were performed to determine the threshold laser pulse energy density resulting in explosive transformation of the mixtures studied. The experiments showed the possibility of using the laser initiation technique for rapid testing of mixtures of variable composition and structure.     

An adaptive partitioning approach for mining discriminant regions in 3D image data

Mining discriminative spatial patterns in image data is an emerging subject of interest in medical imaging, meteorology, engineering, biology, and other fields. In this paper, we propose a novel approach for detecting spatial regions that are highly discriminative among different classes of three dimensional (3D) image data. The main idea of our approach is to treat the initial 3D image as a hyper-rectangle and search for discriminative regions by adaptively partitioning the space into progressively smaller hyper-rectangles (sub-regions). We use statistical information about each hyper-rectangle to guide the selectivity of the partitioning. A hyper-rectangle is partitioned only if its attribute cannot adequately discriminate among the distinct labeled classes, and it is sufficiently large for further splitting. To evaluate the discriminative power of the attributes corresponding to the detected regions, we performed classification experiments on artificial and real datasets. Our results show that the proposed method outperforms major competitors, achieving 30% and 15% better classification accuracy on synthetic and real data respectively while reducing by two orders of magnitude the number of statistical tests required by voxel-based approaches.