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3-Nitro-1,2,4-triazole-5-one (NTO) has received wide attention and has applications owing to its excellent detonation performance and low sensitivity. A new crystal form of NTO was prepared via the solvent evaporation method and named γ-NTO. Its crystal properties were studied through single-crystal X-ray diffraction, and the results indicated that the unit cell of γ-NTO belongs to the monoclinic space group Pc, with eight molecules in the single unit cell. The density of this crystal is calculated to be 1.907 g cm−3, which is higher than that of β-NTO and similar to that of α-NTO. The crystal morphology was calculated to be a polygonal shape with a symmetrical growth pattern using the reactive force field. Based on the analysis of reactive molecular dynamics, the thermal decomposition mechanism of different crystal forms of NTO was elucidated, and the results showed that γ-NTO demonstrates higher gas production, providing a successful way to enhance detonation performance. The results of IR and differential thermal analysis (DTA) support the above conclusions. [ABSTRACT FROM AUTHOR]

Highlights: A Cr5Te8@expanded graphite heterostructure is fabricated by chemical vapor deposition, exhibiting remarkable microwave absorption performance with a minimum reflection loss of up to − 57.6 dB at a thin thickness of only 1.4 mm under a low filling rate of 10%. Density functional theory calculations deeply reveal the polarization loss mechanism triggered by heterogeneous interfaces. The heterostructure coating displays a remarkable radar cross section reduction of 31.9 dB m2, demonstrating a great electromagnetic microwave scattering ability and radar stealth capability. Two-dimensional (2D) transition metal chalcogenides (TMCs) hold great promise as novel microwave absorption materials owing to their interlayer interactions and unique magnetoelectric properties. However, overcoming the impedance mismatch at the low loading is still a challenge for TMCs due to the restricted loss pathways caused by their high-density characteristic. Here, an interface engineering based on the heterostructure of 2D Cr5Te8 and graphite is in situ constructed via a one-step chemical vapor deposit to modulate impedance matching and introduce multiple attenuation mechanisms. Intriguingly, the Cr5Te8@EG (ECT) heterostructure exhibits a minimum reflection loss of up to − 57.6 dB at 15.4 GHz with a thin thickness of only 1.4 mm under a low filling rate of 10%. The density functional theory calculations confirm that the splendid performance of ECT heterostructure primarily derives from charge redistribution at the abundant intimate interfaces, thereby reinforcing interfacial polarization loss. Furthermore, the ECT coating displays a remarkable radar cross section reduction of 31.9 dB m2, demonstrating a great radar microwave scattering ability. This work sheds light on the interfacial coupled stimulus response mechanism of TMC-based heterogeneous structures and provides a feasible strategy to manipulate high-quality TMCs for excellent microwave absorbers. [ABSTRACT FROM AUTHOR]

Although NTO is unquestionably acidic, its potential to corrode weaponry and associated reaction mechanisms remain puzzling. Here, ab initio molecular dynamics (AIMD) with explicit solvation and "slow-growth" sampling approaches are utilized to identify the key steps involved in NTO induced metal corrosion. Our results affirm that the acidity of NTO originates from the lower dehydrogenation barrier of the N4 site compared to the N1 site (0.28 vs. 0.37 eV). Furthermore, NTO has the strongest adsorption on Fe(110) in a nitro-dissociation manner, revealed by using density functional theory (DFT) calculations. Notably, under the catalysis of Fe(110) and hydrogen shuttling, both NTO and its anion can realize the "nitro-to-amino" reaction within 4 ps, but the reduction barrier of the anion is higher. The surface species (*O and *OH) produced by the "nitro-to-amino" reaction serve as corrosion precursors and exacerbate the observed surface iron oxide formation in the experiments. Consequently, the surface corrosion products and azole rings, which are difficult to further decompose under mild conditions, act as a barrier to mitigate the corrosion rate. This work not only unveils a crucial issue in the application of NTO, but also highlights the importance of metal surface and hydrogen bonding in the corrosion process. Our research provides guidance for elaborating the mechanism of NTO induced corrosion at the microscopic level; it may hold for other acidic organic molecules as well. Such understanding can help in establishing corresponding protective measures. [ABSTRACT FROM AUTHOR]

The combination of 3-nitro-1,2,4-triazol-5-one (NTO) and ammonium perchlorate (AP) can effectively utilize the advantages of both materials. The interaction mechanism between NTO and AP is important for the feasibility of combining these materials and can provide theoretical guidance for the design of such a combination. Thus, in order to figure out the interaction mechanism between NTO and AP on multiple scales, density functional theory (DFT) and ab initio molecular dynamic (AIMD) studies have been carried out. Several possible configurations are obtained from a large number of randomly generated NTO and AP dimers using DFT. To understand the interaction mechanism, binding energies, energy decomposition, electrostatic potential (ESP), electron density topology, and independent gradient model based on the Hirshfeld partition (IGMH) analyses were carried out. To have further insights into the combination of NTO and AP, the AIMD method was used to predict the co-crystal structure of NTO and AP, and the electron structure, thermal decomposition, and shock Hugoniot curves were calculated. All the calculation results show the high feasibility of the combination of NTO and AP to form NTO/AP co-crystal with excellent performance. [ABSTRACT FROM AUTHOR]

As an emerging high-energy compound, 3-nitro-1,2,4-triazol-5-one (NTO) is used in military explosives and rocket propellants. However, the strong acidic corrosion of NTO, and the high sensitivity and poor thermostability of its salts, severely restrict their practical applications. Therefore, a novel strategy to design and construct energetic covalent organic frameworks (COFs) is proposed in this study. We have successfully prepared a two-dimensional crystalline energetic COF (named ECOF-1) assembled from triaminoguanidine salt, in which NTO anions are trapped in the porous framework via the ionic interaction and hydrogen bonds. The results show that ECOF-1 exhibits superior thermal stability than energetic salt of NTO. It also exhibits insensitivity and excellent heat of detonation of 7,971.71 kJ·kg−1. ECOF-1 greatly inhibits the corrosiveness of NTO. In prospect, energetic COFs are promising as a functional platform to design high-energy and insensitive energetic materials. [ABSTRACT FROM AUTHOR]

Fast, reproducible, and quantitative performance evaluation of monomolecular energetic materials (EMs) is a significant challenge that limits the tailored applications of EMs and the development of new high-energy-density materials. Here, a small-dose-based alternative method for the detection of the detonation velocity (DV), heat of detonation (HoD), volume of detonation (VoD), detonation pressure (DP), and detonation temperature (DT) from laser-induced shock-wave images combined with a machine learning algorithm is proposed. On the basis of a comprehensive investigation of the time-resolved plume dynamic behavior and spectral emission properties, we concluded that the exothermic chemical reaction associated with detonation occurred at about 25 μs after the laser pulse termination. Moreover, 27 types of explosives were tested to build the prediction model to validate the proposed theory. Our model accurately predicted the explosion parameters with an average relative error of test set (ARETe) of the models for the DV, VoD, and DT of <5%. In particular, the maximum relative error of test set (MRETe) of the quantitative analysis model for the DV and VoD was less than 4%. Our results demonstrate the value of laser-based micro-explosion technology in an explosion testing system and provide an analytic means for estimation of the detonation performance of EMs in a high-speed, less-consumption, low-cost, high-precision, and practical way. [ABSTRACT FROM AUTHOR]

The design and synthesis of energetic materials with a compatibility of high energy and insensitivity have always been the research fronts in military and civilian fields. Considering excellent performances of porous organic frameworks and the lack of research in the field of energetic materials, in this study, a new concept named energetic porous aromatic frameworks (EPAFs) is proposed. The strategy of coating high energy explosives such as 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane (CL-20) and 1,3,5,7-tetranitro-1,3,5,7-tetrazocane (HMX) in the EPAFs by wet-infiltration method has successfully realized the assembly of target energetic composite materials. The results show that the 75 wt.% CL-20@EPAF-1 possesses the safer impact sensitivity of 31.4 J than that of CL-20 (4.0 J). Notably, for 75 wt.% CL-20@EPAF-1, in addition to the superior detonation performances of the detonation velocity (8,761 m·s−1) and detonation pressure (31.27 GPa), the synergistic effect of the nitrogen-rich EPAFs and the nitramines high energy explosives results in a higher heat of detonation that surpasses the most of pristine high explosives and reported novel energetic materials. In prospect, energetic porous aromatic frameworks could be a promising and inspiring strategy to build high energy insensitive energetic materials. [ABSTRACT FROM AUTHOR]

The traditional large-dosage and dangerous methods for the determination of the sensitivities of energetic materials (EMs) have always led to low-accuracy diagnoses with poor repeatability, since they are affected by crystalline quality, experimental conditions, etc. Herein, a simple method is developed to determine various sensitivities, such as impact sensitivity, friction sensitivity, electrostatic sensitivity, and laser sensitivity, via laser spark spectrometry (LSS), with the consumption of only several milligrams of EM, rather than macro-detonation testing. Based on suitable correlated prediction models using the entire LSS spectrum and physical-parameter-corrected statistical regression, the friction sensitivity, electrostatic sensitivity, and laser sensitivity can be well predicted, evaluating the impact of various factors on sensitivity. The correlations between plasma temperature and impact sensitivity, electron density and friction sensitivity, and oxygen balance and electrostatic sensitivity are also clarified. This can facilitate sensitivity predictions with high precision. This method provides a safe, low-dosage, high-precision, and low-cost approach for sensitivity estimations of EMs. [ABSTRACT FROM AUTHOR]

1,1-Diamino-2,2-dinitroethylene (FOX-7) is well-known as one high-energy insensitive material. The size effect of the nano-crystal on the pyrolysis are extremely important for ignition and reaction pathways under extreme conditions. The thermal decomposition of nano-FOX-7 was investigated utilizing molecular dynamics method with reactive force field. The pyrolysis simulation showed that the potential barrier of nano-FOX-7 at 3000 K are higher than that at 2000 K. The temperature distribution of nano-FOX-7 in the temperature-rise periods shows that the decomposition occurs first at the central part of the crystal. Based on the analysis of chemical species, three types of initial reaction pathways were identified, among which the fission of the C–NH2 bond may be a new reaction pathway. A decomposition network from initial reactant to the main products was proposed to provide insights into the decomposition mechanism on atomic level. The mass distribution of products showed that the clusters among the decomposition products can inhibit the violent reaction to a certain extent. In addition, the analysis of the nano-crystal effect on the FOX-7 decay shows that the numbers of N2 and CO2 are related to the nanoparticle size. [ABSTRACT FROM AUTHOR]

The rapid development of modern electronic technology has provided high efficiency for social production, but it also brings serious electromagnetic interference (EMI). Although traditional metals and their alloys can serve as good electromagnetic shielding materials, their heavy weight, high cost as well as poor corrosion resistance limit their application in EMI shielding. Therefore, electromagnetic shielding materials with lightweight are gradually attracting more and more attention to meet the trend of lightweight and highly integrated electronic equipment. Polymers are widely used in EMI shielding materials because of their unique characteristics, such as lightweight, high flexibility and excellent corrosion resistance. This review is focused on the well-studied polymer-based lightweight composites, with the aim of providing a comprehensive review of the existing EMI shielding mechanism, preparation and application of polymer-based lightweight composites, along with retrieving new general insights into the advantages and limitations associated with the different measurement and prediction techniques, as well as the EMI shielding effectiveness of polymer-based lightweight composites including metal-containing composites, intrinsic conductive polymers, filler-containing polymers and newly discovered materials. These lightweight materials with fine EMI shielding performance will find more and more potential applications in communications, electronics, aerospace, military, environmental protection, etc. [ABSTRACT FROM AUTHOR]

The differential scanning calorimetry (DSC) was used to investigate the specific heat capacity of 5,5′-dinitramino-3,3′-bi[1,2,4-triazolate] carbohydrazide salt (CBNT) from 25 to 55 °C. The relationship can be described as Cp = 1.26324 + 0.0014 × T, 25 °C ≤ T ≤ 55 °C. Moreover, the thermal characteristics and kinetics of CBNT were studied using DSC and accelerating rate calorimetry (ARC). DSC results showed that the thermal decomposition occurred at 200.03, 203.75, 206.25 and 208.54 °C at different heating rates (0.5, 1.0, 1.5 and 2.0 °C min−1), respectively. The apparent activation energy (Ea) and pre-exponential factor (A), calculated using the Kissinger method, were 303.01 kJ mol−1 and 2.37 × 1032 s−1, respectively. The apparent activation energy, calculated using the Ozawa equation, was 295.64 kJ mol−1. ARC test indicated that the self-decomposition reaction of CBNT started at 180.8 °C and lasted for 497 min, during which the maximum temperature rise rate was 0.08 °C min−1 and the pressure rise rate was 2.04 kPa min−1. Moreover, rate constant method and mechanism functions method were applied to calculate kinetic parameters, among which the most possible mechanism functions were (1 − α)2. The values of Ea for the decomposition of CBNT calculated by these two methods were 420.78 and 420.73 kJ mol−1. The values of A were 5.13 × 1043 and 3.04 × 1045 s−1, respectively. In addition, the self-accelerating decomposition temperature of CBNT based on ARC data in the packages of 25, 50 and 75 kg was 195.23, 194.10 and 193.10 °C, respectively. [ABSTRACT FROM AUTHOR]

Multifunctional nanocarrier‐based theranostics have been proposed to overcome some key problems in cancer treatments. In this contribution, a facile approach is reported to synthesize carbon dots‐mesoporous silica nanohybrids (named MSNs‐CDs) via a one‐pot microwave heating reaction of amino‐functionalized mesoporous silica nanoparticles (MSNs‐NH2) and citric acid in formamide. The MSNs‐CDs nanohybrids exhibit capabilities of multicolor/two‐photon imaging, high photothermal conversion under NIR laser irradiation (671 nm), and anti‐cancer drug delivery, and thus could potentially be applied as a multifunctional nanocarrier‐based theranostic agent for cancer. Further studies revealed that CDs were in situ formed on the surface of MSNs during the reaction, which is amenable for the observed multicolor/two‐photon imaging and photothermal properties. Besides, the well‐preserved MSNs characters of MSNs‐CDs nanohybrids (e. g. mesoporous structure, large surface area and pore volume) enable them to be an ideal nanocarrier for delivering anti‐cancer drugs, such as doxorubicin (DOX). Importantly, the MSNs‐CDs@DOX exhibited pH‐ (lower pH being preferred) and thermo‐responsive DOX release behaviors, which would effectively decrease side effects and meanwhile enhance the efficacy of chemotherapy due to the weak acidic microenvironment of tumor and photothermal effect of the CDs. Finally, in vitro experiments exhibited that the highest therapeutic efficacy was obtained by MSNs‐CDs@DOX with NIR irradiation, attributing to the synergistic effect of chemotherapy and PTT. This study not only provides a facile method to prepare CDs and MSNs nanohybrids, but also demonstrates that both of the superior features and functions of CDs and MSNs could be preserved and combined, which are deemed to be beneficial for the development of multifunctional theranostic nanoplatform for cancers. [ABSTRACT FROM AUTHOR]

To study the influence of twinned crystals on the performance of TKX-50, normal TKX-50 (N-TKX-50) and twinned TKX-50 (T-TKX-50) supercells are constructed, and ReaxFF-lg reactive molecular dynamics simulations are performed to study the thermal decomposition and oxidation of N-TKX-50 and T-TKX-50 at 1000, 2000 and 3000 K. The mechanism of thermal decomposition and oxidation of N-TKX-50 and T-TKX-50 are analyzed in terms of potential energy evolution, primary reaction paths, and the intermediate and final products. We find that T-TKX-50 possesses higher decomposition and consumption rate than N-TKX-50 at the same temperature conditions, while the decomposition and the oxidation end-products of N-TKX-50 and T-TKX-50 are the same. These results confirm that the T-TKX-50 crystal is unfavorable for the thermal stability of TKX-50. We believe that this work can provide some guidance for investigating the decomposition and oxidation of other materials. [ABSTRACT FROM AUTHOR]

Thermal decomposition study of diammonium 5,5′-bistetrazole-1,1′-diolate (ABTOX) was investigated by using DSC. The result showed that ABTOX is less thermal sensitive than TKX-50. The kinetic parameters (E = 139.82 kJ mol−1 and lgA = 12.75 s−1) for thermal decomposition reaction of ABTOX were obtained. The compatibility of ABTOX with 1,3,5-trinitro-1,3,5-triazacyclohexane (RDX), 1,3,5,7-tetranitro-1,3,5,7-tetraazacyclooctane (HMX), 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaza-isowurtzitane (CL-20), 3-nitro-1,2,4-triazol-5-one (NTO), 1,1-diamino-2,2-dinitroethene (FOX-7), 2,6-diamino-3,5-dinitropyrazine-1-oxide (LLM-105), aluminum powder (Al), Estane-TPU-5702 and two kinds of fluoropolymers (F-2311 and F-2603) were evaluated by using DSC. The results showed that CL-20/ABTOX, FOX-7/ABTOX and F-2603/ABTOX were exhibiting good compatibility and RDX/ABTOX and Al/ABTOX had moderate compatibility. In addition, the compatibility of ABTOX with Estane-TPU-5702 and F-2311 was not good. HMX/ABTOX, NTO/ABTOX and LLM-105/ABTOX had poor compatibility. Furthermore, the self-accelerating decomposition temperature was calculated to be 152 °C and 150 °C in commercial wooden and PE cylinder, respectively. [ABSTRACT FROM AUTHOR]

The primary decomposition product (TKX-50-M) of dihydroxylammonium 5,5′-bistetrazole-1,1′-diolate (TKX-50) was obtained under adiabatic condition by using accelerating rate calorimeter (ARC). Meanwhile, diammonium 5,5′-bistetrazole-1,1′-diolate (ABTOX) was confirmed as the main component of TKX-50-M. Specific heat capacity of TKX-50-M and ABTOX was studied from 0 to 45 °C. In addition, the thermal decomposition of TKX-50-M and ABTOX was studied under adiabatic condition. The experiment results revealed that TKX-50-M were more thermal sensitive than ABTOX. Furthermore, ABTOX exhibited much violent than that of TKX-50-M during decomposition. [ABSTRACT FROM AUTHOR]

The thermal decomposition behaviors of 2,4,6-Trinitrotoluene (TNT) and 1-methoxy-2,4-dinitro-benzene (DNAN) were studied by using a NETSCH company accelerating rate calorimetry. Hazard indicators such as onset temperature, adiabatic temperature rise, initial self-heat temperature, maximum self-heating rate, and time-to-maximum temperature rise rate have been determined directly. The kinetic parameters, such as the activation energy ( E ) and the pre-exponential factor ( A) were studied from the measured self-heating rate data by assuming order reaction. [ABSTRACT FROM AUTHOR]

TKX-50/GO composite was prepared and characterized. The results suggested that the morphology of TKX-50 was improved from tabular crystal to polyhedron after coating with GO. The thermal stability of TKX-50/GO composite was essentially unchanged. Both impact sensitivity and friction sensitivity of TKX-50/GO composite was more insensitive than those of TKX-50. [ABSTRACT FROM AUTHOR]

Thermogravimetric-differential scanning calorimeter and accelerating rate calorimeter (ARC) were performed to study the thermal characteristics and kinetics of energetic 5,5′-bistetrazole-1,1′-diolate (1,1-BTO). The DSC measurements showed one endothermic peak and one exothermic peak with decomposition occurring at 219.1, 227.2, 234.0 and 244.1 °C at different heating rates (2, 4, 8 and 15 °C min). The value of critical temperature of thermal explosion ( T ) and kinetics parameters was calculated, suggesting that 1,1-BTO is stable below the temperature of 175.36 °C. The thermal behavior under adiabatic condition was studied by ARC, depicting that onset temperature was 176.61 °C and the thermal decomposition ended at 215.93 °C, within the time span of 49.04 min. In addition, the thermo-kinetic parameters such as the activation energy E and pre-exponential factor A under adiabatic condition were also obtained. [ABSTRACT FROM AUTHOR]

The enthalpies of dissolution for dihydroxylammonium 5, 5′-bistetrazole-1,1′-diolate (TKX-50) in water were measured using a C-80 Calvet microcalorimeter at four different temperatures under atmospheric pressure. Differential enthalpies (Δ H) and molar enthalpies (Δ H) of dissolution were calculated. The corresponding kinetic equations that describe the dissolution rate at the four experimental temperatures are d α/d t = 10(1 − α) ( T = 298.15 K), d α/d t = 10(1 − α) ( T = 303.15 K), d α/d t = 10(1 − α) ( T = 308.15 K), d α/d t = 10(1 − α) ( T = 313.15 K). In addition, the determined values of the activation energy E and pre-exponential factor A for the dissolution process are 25.08 kJ mol and 21.98 s, respectively. [ABSTRACT FROM AUTHOR]

The thermal behavior and decomposition kinetics of CL-20-based plastic-bonded explosives (PBXs) composed of main explosive CL-20 and additives were first time explored by means of DSC, TG and ARC techniques. The DSC study at different heating rates was performed and showed the effect of the additives on the exothermic peaks of CL-20-based PBXs. The thermal stability of CL-20-based PBXs was evaluated by DSC, TG and ARC, indicating that the largest influence on lowering the activation energy is the presence of plasticizer. The kinetic parameters after addition of additives were compared with those of raw CL-20 by means of Kissinger and Ozawa methods. Moreover, the mechanical sensitivities of investigated CL-20-based PBXs were supported, which was well consistent with the data from DSC and ARC measurements. [ABSTRACT FROM AUTHOR]

The enthalpies of dissolution for 5,5′-Bistetrazole-1, 1′-dihydroxy ((HO)BTO) and disodium 5,5′-Bistetrazole-1,1′-diolate ([Na(HO)]BTO) in dimethyl sulfoxide (DMSO) at 298.15 K were studied by using a C-80 Calvet microcalorimeter. Empirical formulae for the calculation of the molar enthalpies of dissolution (Δ H), relative partial molar enthalpies (Δ H ), and relative apparent molar enthalpies (Δ H ) were deduced by the experimental results of the dissolution processes of (HO)BTO and [Na(HO)]BTO in DMSO. Finally, the corresponding kinetic equations describing the dissolution processes were dα/dt = 10(1− α) for the dissolution of (HO)BTO in DMSO, and dα/dt = 10(1− α) for the dissolution of [Na(HO)]BTO in DMSO. [ABSTRACT FROM AUTHOR]

Thermal decomposition of melted 3,4-bis(3-nitro-furazan-4-yl)furoxan (DNTF) in near adiabatic environment was first time investigated by using accelerating rate calorimeter. Based on the experimental results, the kinetic parameters of exothermic reaction of DNTF under adiabatic condition were calculated. The thermal decomposition parameters, including the initial decomposition temperature, the adiabatic temperature rise and the maximum temperature rise rate, were obtained from the thermal inertia factor. The adiabatic experiment revealed that DNTF has a relatively high initial exothermic decomposition temperature at 180.7 °C. The apparent activated energy Ea and pre-exponential factor A were calculated as 197.54 kJ mol and 7.68 × 1016 s, respectively. In addition, self-accelerating decomposition temperature and 5-s delay exploding point of DNTF were also provided, which is consistent with the data obtained by the traditional Wood's alloy bathy method. [ABSTRACT FROM AUTHOR]

Thermal decomposition study of dihydroxylammonium 5,5′-bistetrazole-1,1′-diolate (TKX-50) was investigated by using TG-DTG and TG-IR-MS and found that N, NO, NH and HO were the main products during the decomposition process. The kinetic parameters ( Ea = 138.96 kJ mol and A = 10 s) for thermal decomposition reaction of TKX-50 were obtained from DSC profile by differential method and integral method, and the nonisothermal kinetic equation of the exothermic process was $${\text{d}}\alpha /{\text{d}}T = (10^{12.93} /\beta )3(1 - \alpha )[ - \ln (1 - \alpha )]^{2/3} \exp ( - 1.6713 \times 10^{4} /T),$$ suggesting that the main exothermic decomposition reaction mechanism of TKX-50 was classified as Avrami-Erofeev equation. In addition, the theoretical detonation velocity ( D = 8804 m/s) of TKX-50 at 298.15 K was calculated by a simple method. Finally, the safety parameters of TKX-50 (25 kg) including time to maximum rate under adiabatic conditions and self-accelerating decomposition temperature were calculated to be 142.12 and 129.01 °C by using AKTS software. [ABSTRACT FROM AUTHOR]

The thermal decomposition behaviors of 4,10-dinitro-2,6,8,12-tetraoxa-4,10-diazaisowutrzitane (TEX) were studied by using accelerating rate calorimetry to achieve the hazard assessment of TEX explosive, and the kinetic parameters were studied from the measured self-heating rate data by assuming a zero-order reaction. Moreover, the specific heat capacity date of TEX was obtained from differential scanning calorimetry. These results could be contributed to improve the safety in the reaction, transportation, and storage processes of TEX. [ABSTRACT FROM AUTHOR]

A novel nitroamine/energetic ionic salt cocrystal explosive containing CL-20 and 1-AMTN in a 1 : 1 molar ratio is presented. The structure of this cocrystal is determined by single-crystal X-ray diffraction (SC-XRD). The predicted detonation performance is slightly higher than that of RDX, a state-of-the-art explosive. In small-scale impact drop tests, the cocrystal exhibits a surprisingly low sensitivity relative to CL-20. These features make this cocrystal a very promising explosive to replace RDX. [ABSTRACT FROM AUTHOR]

The dissolution and thermochemical properties of dihydroxylammonium 5,5ʹ-bistetrazole-1,1ʹ-diolate (TKX-50) and its intermedium disodium 5,5ʹ-bistetrazole-1,1ʹ-diolate ([Na2(H2O)4]BTO) in water at 298.15 K were studied using a C-80 Calvet microcalorimeter. Empirical formulae for the calculation of the molar enthalpies of dissolution (ΔdissH), relative partial molar enthalpies (ΔdissHpartial), and relative apparent molar enthalpies (ΔdissHapparent) were deduced by the experimental results of the dissolution processes of TKX-50 and [Na2(H2O)4]BTO in water. Finally, the corresponding kinetic equations describing the dissolution processes weredα/dt = 10−2.95(1 − α)0.64for the dissolution of TKX-50 in water anddα/dt = 10−2.76(1 − α)1.07for the dissolution of [Na2(H2O)4]BTO in water. [ABSTRACT FROM AUTHOR]

4,4-azo-bis(1,2,4-triazol-5-one) (ZTO) and its solvent adducts have been reported, and the single crystal X-ray measurements indicated that the ZTO crystals appeared as a monoclinic system with space group P2(1)/c, while ZTO·2HO and ZTO·2DMF displayed as monoclinic with space group P2(1)/n and triclinic with space group Pī, respectively. In addition, the thermal decomposition process of the three crystals was studied by thermogravimetric differential analysis (TG-DTA), and the result showed that only one exothermic peak was found in each case of ZTO, ZTO·2HO, and ZTO·2DMF, and the peak temperature ( T) are observed at 292.36, 291.82, and 272.73 °C, respectively. [ABSTRACT FROM AUTHOR]

4,4′-Azo-bis(1,2,4-triazolone) (ZTO) based salts from alkaline (Li+, K+, Na+, and Cs+), alkaline earth metal salts (Mg2+, Ca2+, Sr2+, and Ba2+) and hydrazinium salt were synthesized in a simple, straightforward manner and were characterized by IR and NMR spectroscopy, elemental analysis. The single-crystal X-ray diffraction of seven salts (Na+, K+, Cs+, Mg2+, Ca2+, Sr2+, Ba2+, and N2H5+) are also reported. The X-ray structures show that in the title compounds, the metal atoms are bonded to the nitrogen and oxygen atoms in the bistetrazole ring to form a sandwich structure. In addition, the thermal stabilities of all the title compounds were determined using thermogravimetric-differential thermal analysis (TG-DTA). All these new materials exhibit excellent thermal stability, high density, acceptable detonation properties, and excellent insensitivity to impact (h50 ＞ 60 cm). In particular, the barium, caesium and strontium salts are of great interest as potential high-density insensitive materials. [ABSTRACT FROM AUTHOR]

A new crystal form of diammonium 5,5′-bistetrazole-1,1′-diolate ( 1) was prepared by two novel methods and fully characterized by using IR, NMR spectroscopy, elementary analysis, single crystal X-ray crystallography and thermal gravity/differential thermal analysis (TG/DTA). Crystalline 1 was found as monoclinic and space group of P21/ c (14). The TG/DTA analysis showed that the decomposition temperature of 1 was 287.8°C with a mass loss of 91.2% in the range of 220-300°C at a heating rate of 5°C/min. The sensitivities test towards impact, friction of 1 indicated that 1 has much lower sensitivities than those of RDX/HMX and is comparable to those of TNT, which suggested that 1 could be used as a good candidate of new insensitive energetic compound. [ABSTRACT FROM AUTHOR]

An amendment to this paper has been published and can be accessed via the original article. [ABSTRACT FROM AUTHOR]

An amendment to this paper has been published and can be accessed via the original article. [ABSTRACT FROM AUTHOR]

An amendment to this paper has been published and can be accessed via the original article. [ABSTRACT FROM AUTHOR]

An amendment to this paper has been published and can be accessed via the original article. [ABSTRACT FROM AUTHOR]

An amendment to this paper has been published and can be accessed via the original article. [ABSTRACT FROM AUTHOR]

An amendment to this paper has been published and can be accessed via the original article. [ABSTRACT FROM AUTHOR]

The polynitro imidazole derivative 1,5-dinitro-2,6-bis(trinitromethyl)-3a,4a,7a,8a-tetrahydro-[1,4]dioxino[2,3-d:5,6-d′]diimidazole (DNTNDI) was synthesized through nitration of 2-(dinitromethylene)-1H-imidazol-4-ol in HNO3/Ac2O followed by cyclization of the di-enol. It was characterized by NMR, IR, elemental analysis, and single-crystal X-ray diffraction analysis. Compound DNTNDI crystallizes in the orthorhombic space group P2(1)2(1)2(1). The thermal decomposition was studied with thermogravimetry/derivative thermogravimetry (TG/DTG) in a nitrogen atmosphere with a heating rate of 5 K min−1. The TG/DTG analysis indicated that DNTNDI has 97.64 % mass loss between 127 °C and 173 °C by undergoing exothermic decomposition. The density of DNTNDI was determined as 1.906 g cm−3 at 293 K with an Ultrapycno 1000 Pycnometer. The denotation velocity and denotation pressure of DNTNDI were calculated as 9325 m s−1 and 40 GPa by applying the LOTUSES (version 1.4) code, respectively. The oxygen balance of DNTNDI is 0 and its oxygen content amounts to 51.78 %, which is superior to that of new generation of chlorine-free oxidizer ammonium dinitramide (ADN). [ABSTRACT FROM AUTHOR]

An electrochemiluminescent sensing scheme is presented for remote detection of Hg2+ through an ITO-coated nanostructured optical fibre bundle. It is based on the electropolymerisation of CPDT-linked ruthenium phenanthroline complexes carrying azacrown ethers as the receptor units (CPDT = 4H-cyclopenta[2,1-b:3,4-b′]dithiophene). The application of an anodic potential simultaneously induces electrogenerated chemiluminescence (ECL) and turns off the absorbance of the polymer backbone at the ECL emission wavelength. Therefore, the electropolymer film allows ECL light generation and transmission for efficient remote sensing in a synergetic way. As a proof of concept, selective detection of Hg2+ was demonstrated remotely by ECL through an optical fibre bundle. [ABSTRACT FROM AUTHOR]

Bladder cancer is a significant public health concern and social burden due to its high recurrence risk. Intravesical drug instillation is the primary therapy for bladder cancer to prevent recurrence. However, the intravesical drug therapeutic effect is limited by bladder penetrating barriers. The inadequate intravesical treatment might cause the low drug concentration in lesions, resulting in a high recurrence/progression rate of bladder cancer. Many strategies to get drugs across bladder penetrating barriers have been developed to improve intravesical treatment, including physical and chemical methods. This review summarizes the classical and updated literature and presents insights into great therapeutic potential strategies to overcome bladder penetrating barriers for improving the intravesical treatment of bladder cancer. [ABSTRACT FROM AUTHOR]

In this study, sulfur-free expanded graphite (EG) was obtained by using flake graphite as the raw material, and EG/Fe3O4 composites with excellent microwave absorption properties were prepared by a facile one-pot co-precipitation method. The structure and properties of as-prepared EG/Fe3O4 were investigated by scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared (FT-IR), X-ray diffraction (XRD), Raman, X-ray photoelectron spectrometry (XPS), thermogravimetric (TG), and vibrating sample magnetometry (VSM) characterizations. The Fe3O4 intercalated between the layers of expanded graphite forms a sandwich-like structure which is superparamagnetic and porous. When applied as a microwave absorber, the reflection loss (RL) of EG/Fe3O4 reaches −40.39 dB with a thickness of 3.0 mm (10 wt% loading), and the effective absorption bandwidth (EAB < −10 dB) with RL exceeding −10 dB is 4.76–17.66 GHz with the absorber thickness of 1.5–4.0 mm. Considering its non-toxicity, easy operation, low cost, suitability for large-scale industrial production, and excellent microwave absorbing performance, EG/Fe3O4 is expected to be a promising candidate for industrialized electromagnetic absorbing materials. [ABSTRACT FROM AUTHOR]

C6H5N11O6, monoclinic, P21/ n (no. 14), a = 13.463(5) Å, b = 6.526(2) Å, c = 14.068(5) Å, β = 95.961(5)°, V = 1229.3(7) Å3, Z = 4, Rgt (F) = 0.0417, wRref (F2 ) = 0.1067, T = 153 K. [ABSTRACT FROM AUTHOR]

C2H12N8O8Mg, orthorhombic, Pbcn, a = 9.858(8) Å, b = 6.852(5) Å, c = 18.276(3) Å, V = 1185.6(16) Å3, Z = 4, Rgt( F) = 0.0245, wRref( F2) = 0.0693, T = 293(2) K. [ABSTRACT FROM AUTHOR]