A Comprehensive Study of the Electrostatic Discharge Sensitivity and Chargeability of Tris(carbohydrazide)zinc Perchlorate

Abstract: Most primary explosives are non-conductors, easily accumulate charge when contacting with and separating from other materials, and are sensitive to electrostatic discharge (ESD). In order to reduce the number of accidents caused by ESD initiation of primary explosives, studies on their electrostatic hazards are necessary. This work presents comprehensive experimental results of electrostatic discharge sensitivity and chargeability of tris(carbohydrazide)zinc perchlorate (ZnCP) under different conditions. The influences of the testing conditions, of devices, particle size, ambient temperature and relative humidity on the electrostatic discharge sensitivity and chargeability have been investigated in detail, and the quantitative regression equations obtained

An Efficient Numerical Approach for Field Infrared Smoke Transmittance Based on Grayscale Images

Infrared smoke screen has been playing an important role in electro-optical countermeasures on the battlefield. Smoke transmittance is one of the most important parameters which can evaluate the obscuration performance of smoke. In this paper, an efficient numerical approach for field infrared smoke transmittance based on grayscale images is presented. Firstly, a field trial experimental setup is introduced. Then a grayscale smoke transmittance mathematical model is deduced and built. In addition, an image processing algorithm is used to extract the gray values of certain pixel points from grayscale images, and the positions of the selected points are discussed. Lastly, a field trial sample calculation is included to illustrate the procedure of the proposed method. The results prove to be of enough precision for engineering applications, and the method has greatly simplified the field trial process, thus improving efficiency

Infrared Thermography Approach for Effective Shielding Area of Field Smoke Based on Background Subtraction and Transmittance Interpolation

Effective shielding area is a crucial indicator for the evaluation of the infrared smoke-obscuring effectiveness on the battlefield. The conventional methods for assessing the shielding area of the smoke screen are time-consuming and labor intensive, in addition to lacking precision. Therefore, an efficient and convincing technique for testing the effective shielding area of the smoke screen has great potential benefits in the smoke screen applications in the field trial. In this study, a thermal infrared sensor with a mid-wavelength infrared (MWIR) range of 3 to 5 μm was first used to capture the target scene images through clear as well as obscuring smoke, at regular intervals. The background subtraction in motion detection was then applied to obtain the contour of the smoke cloud at each frame. The smoke transmittance at each pixel within the smoke contour was interpolated based on the data that was collected from the image. Finally, the smoke effective shielding area was calculated, based on the accumulation of the effective shielding pixel points. One advantage of this approach is that it utilizes only one thermal infrared sensor without any other additional equipment in the field trial, which significantly contributes to the efficiency and its convenience. Experiments have been carried out to demonstrate that this approach can determine the effective shielding area of the field infrared smoke both practically and efficiently

Nitrogen-Rich Salts Based on the Energetic [Monoaquabis(<i>N</i>,<i>N</i>‑bis(1<i>H</i>‑tetrazol-5-yl)amine)-zinc(II)] Anion: A Promising Design in the Development of New Energetic Materials

Nitrogen-rich energetic salts involving various cations (lithium, <b>1</b>; ammonium, <b>2</b>; hydrazinium, <b>3</b>; hydroxylammonium, <b>4</b>; guanidinium, <b>5</b>; aminoguanidinium, <b>6</b>; diaminoguanidinium, <b>7</b>; and triaminoguanidinium, <b>8</b>) based on nitrogen-rich anion [Zn­(BTA)₂(H₂O)]^2– (N% = 65.37, BTA = <i>N</i>,<i>N</i>-bis­[1<i>H</i>-tetrazol-5-yl]­amine anion) were synthesized with a simple method. The crystal structures of all compounds except <b>1</b>, <b>2</b>, and <b>6</b> were determined by single-crystal X-ray diffraction and fully characterized by elemental analysis and FT-IR spectroscopy. The thermal stabilities were investigated by differential scanning calorimetry (DSC). The DSC results show that all compounds exhibit high thermal stabilities (decomposition temperature >200 °C). Additionally, the heats of formation were calculated on the basis of the experimental constant-volume energies of combustion measured by using bomb calorimetry. Lastly, the sensitivities toward impact and friction were assessed according to Bundesamt für Materialforschung (BAM) standard methods

Nitrogen-Rich Salts Based on the Energetic [Monoaquabis(<i>N</i>,<i>N</i>‑bis(1<i>H</i>‑tetrazol-5-yl)amine)-zinc(II)] Anion: A Promising Design in the Development of New Energetic Materials

Nitrogen-rich energetic salts involving various cations (lithium, <b>1</b>; ammonium, <b>2</b>; hydrazinium, <b>3</b>; hydroxylammonium, <b>4</b>; guanidinium, <b>5</b>; aminoguanidinium, <b>6</b>; diaminoguanidinium, <b>7</b>; and triaminoguanidinium, <b>8</b>) based on nitrogen-rich anion [Zn­(BTA)₂(H₂O)]^2– (N% = 65.37, BTA = <i>N</i>,<i>N</i>-bis­[1<i>H</i>-tetrazol-5-yl]­amine anion) were synthesized with a simple method. The crystal structures of all compounds except <b>1</b>, <b>2</b>, and <b>6</b> were determined by single-crystal X-ray diffraction and fully characterized by elemental analysis and FT-IR spectroscopy. The thermal stabilities were investigated by differential scanning calorimetry (DSC). The DSC results show that all compounds exhibit high thermal stabilities (decomposition temperature >200 °C). Additionally, the heats of formation were calculated on the basis of the experimental constant-volume energies of combustion measured by using bomb calorimetry. Lastly, the sensitivities toward impact and friction were assessed according to Bundesamt für Materialforschung (BAM) standard methods