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C19H18N2O, orthorhombic, Pna21 (no. 33), a = 21.838(2) Å, b = 13.9663(11) Å, c = 4.9806(4) Å, V = 1519.1(2) Å3, Z = 4, Rgt(F) = 0.0702, wRref(F2) = 0.1948, T = 293 K. [ABSTRACT FROM AUTHOR]

C22H14Cl2F4N2Pt, monoclinic, P21/n (no. 14), a = 16.858(9) Å, b = 14.876(8) Å, c = 17.125(9) Å, β = 98.552(6)°, V = 4247(4) Å3, Z = 8, Rgt(F) = 0.0337, wRref(F2) = 0.0778, T = 296 K. [ABSTRACT FROM AUTHOR]

Multiple dangerous sites often coexist in complex structures like aircraft turbine rotors, and its failure-correlated reliability evaluation usually occurs the thorny problems of high-efficacy computing and correlation quantification. In this paper, a novel unified reliability evaluation framework is proposed: to meet the high-efficacy computing demand of multi-site reliability evaluation, a new optimized Kriging surrogate-based improved importance sampling (OKS-IIS) method is first presented; furthermore, to quantify the failure correlation relationships among multiple dangerous sites, a novel failure correlation analysis (FCA) strategy is further developed. A typical reliability evaluation of high-pressure turbine rotor with multiple dangerous sites is selected, to validate the effectiveness of the proposed framework. Methods comparison show that the OKS-IIS method can improve computing efficiency while keeping computing accuracy, and the FCA strategy can accurately quantify the multi-site failure correlation. The current efforts would shed a light on the complex reliability evaluation problems involving failure correlation. [ABSTRACT FROM AUTHOR]

This study investigated the effect of sodium carboxymethyl cellulose (CMC) addition to breadcrumbs. Oil absorption, moisture content and quality characteristics of breadcrumbs were measured, changes in microstructure after frying were analyzed using scanning electron microscopy (SEM), and the effects of CMC addition on the physicochemical properties and structure of wheat gluten proteins were analyzed. Our results showed that the addition of 1.5% CMC reduced the oil absorption of breadcrumb samples from 19.80% to 11.39%. Additionally, the crispiness of the breadcrumbs increased from 21,405.33 to 33,978.09 g/s, while the whiteness value improved from 40.35 to 43.81. Furthermore, CMC incorporated breadcrumb samples had lower bound water content and experienced less water loss during frying which was accompanied by the denser microstructure. The activity of gluten proteins was also determined, the results showed that at 1.5% CMC, surface hydrophobicity reduced from 1952.36 to 1173.66, sulfhydryl content decreased from 1.15 to 0.88, and β-folding declined from 26.76 to 25.78. These changes suggest that CMC, being a hydrophilic colloid, enhanced the hydrophilic ability of the breadcrumbs. The incorporation of CMC into breadcrumbs appears to be a promising strategy for reducing oil absorptivity and improving the overall quality of the breadcrumbs. [Display omitted] • 1.5% CMC reduced the oil absorption rate of the breadcrumbs samples from 19.80% to 11.39%. • After CMC addition, crispiness and whiteness value were improved. • CMC incorporated breadcrumbs samples had lower bound water content and denser microstructure. • At 1.5% CMC, surface hydrophobicity, sulfhydryl content, and β-folding declined. • CMC, being a hydrophilic colloid, enhanced the hydrophilic ability of the breadcrumbs. [ABSTRACT FROM AUTHOR]

Cloud computing has achieved rapid development in recent years, and the use of cloud platforms to carry various large-scale services has become the general trend of the development of the information industry. This study investigates WTP of Hangzhou residents for the recreational value of Baguatian productive landscapes based on CVM and cloud computing. In this study, we did the related analysis on the social and economic characteristics and WTP of interviewees and made the monetization assessment about the recreational value of its urban productive landscapes. The result shows 62.1% of interviewees have WTP and the average payment intention (WTP) is $40.74 per year. Besides, the total recreational value of Hangzhou Baguatian productive landscapes is 354 million yuan; the relatively accepted payment mode is tax-paying and cash payment; the educational degree, occupational background, and income are the main factors influencing the tourists' WTP and the correlation between interviewees' origin, permanent residence, and WTP is not apparent. [ABSTRACT FROM AUTHOR]

Density functional theory (DFT) methods were employed to design a new family of wing-like and propeller-like multi-tetrazole molecules based on the combination of N-center multi-tetrazole and various energetic groups. The optimized geometry, electronic properties, and thermodynamics were calculated for investigating the molecular stability and chemical reactivity. Their energetic parameters including density, heats of formation, detonation properties, and impact sensitivity were extensively evaluated, and the effects of energetic groups were investigated as well. These newly designed wing-like and propeller-like multi-tetrazole molecules exhibit acceptable oxygen balance, moderate impact sensitivities, high density, excellent heats of formation, and good detonation performance. Especially, B3, B4, B5, and B6 are very helpful for enhancing their detonation performance (D ≥ 9500 m·s−1, P ≥ 41 GPa) are promising candidates for new environmentally friendly HEDMs. [ABSTRACT FROM AUTHOR]

[Display omitted] • Interrelationships among physicochemical, volatiles and metabolites. • A total of 43 volatile compounds, mainly alcohols and esters, were identified. • Increase in phenylethyl alcohol led to a rose-like fresh scent. • Biosynthesis of Val, Leu and Ile and metabolism of Ala, Asp and Glu are key pathways. This work set out to investigate how the physicochemical markers, volatiles, and metabolomic characteristics of mixed fermented the fermentation of Lycium barbarum and Polygonatum cyrtonema compound wine (LPCW) from S. cerevisine RW and D. hansenii AS2.45 changed over the course of fermentation. HS-SPME-GC–MS combined with non-targeted metabolomics was used to follow up and monitor the fermentation process of LPCW. In total, 43 volatile chemical substances, mostly alcohols, esters, acids, carbonyl compounds, etc., were discovered in LPCW. After 30 days of fermentation, phenylethyl alcohol had increased to 3045.83 g/mL, giving off a rose-like fresh scent. The biosynthesis of valine, leucine, and isoleucine as well as the metabolism of alanine, aspartic acid, and glutamic acid were the major routes that led to the identification of 1385 non-volatile components in total. This study offers a theoretical foundation for industrial development and advances our knowledge of the fundamental mechanism underlying flavor generation during LPCW fermentation. [ABSTRACT FROM AUTHOR]

For structures with both random and fuzzy uncertainty parameters, a novel method for obtaining the membership function of reliability in the fuzziness failure criterion is presented using a Random Fuzzy Support Vector Machine based on the Particle Swarm Optimization method (PSO-RFSVM). The proposed method is used to solve the structural reliability problem with implicit limit state function in the presence of mixed variables. Under each cut level, a new distance measure between the mixed variables is presented, named the advanced Yang distance; then, the RFSVM model can be constructed using the kernel function built by the advanced Yang distance and random fuzzy mixed sampling points. Furthermore, to obtain satisfactory fitting, a PSO algorithm is used to optimize the super-parameters in RFSVM. The limit state function is subsequently approximated at the given cut level, and then, the reliability bound under the given cut level is readily obtained. The PSO-RFSVM method provides a new efficient analysis framework in the case of implicit approximation under mixed uncertainty when the classical method has excessive consumption in virtual prototype simulation. Two examples are used to demonstrate the validity and advantage of PSO-RFSVM compared to the Extreme Response Surface based on Simulated Annealing (SAERS) method and Monte Carlo simulation (MCS). [ABSTRACT FROM AUTHOR]

With the ongoing progress in modern weaponry, the utilization of 2,4,6-trinitrotoluene (TNT) as a carrier for melt-cast explosives is no longer sufficient to meet these requirements. This review provides a comprehensive overview of melt-cast explosive carriers developed by researchers in the past decade, which demonstrate exceptional overall performance. This review offers a comprehensive summary of the physicochemical properties, detonation performance, safety parameters, and synthetic routes of the carriers mentioned above. By summarizing the structures of these carriers, they can be categorized into four major groups: fluorinated compounds, oxazole compounds, fragment combination compounds, and stereoisomers. The advantages and disadvantages of the four main categories of compounds were analyzed and discussed, with the aim of providing a reference for the development of new melt-cast explosive carriers. [ABSTRACT FROM AUTHOR]

A series of 1-amino-1,2,3-triazole (ATZ) based energetic nitrogen-rich salts are prepared by using acid-base neutralization reaction (1:1 M ratio), and fully characterized. Structures of the salts are recrystallized and determined by single-crystal X-ray diffraction, which dominated by a strong hydrogen-bond influence with the densities ranging from 1.692 to 1.868 g cm −3 . Thermal behaviors have characterized by using the DSC and TG-DTG technologies. The enthalpies of formation have calculated by using Gaussian 03. The detonation parameters of the salts are determined by using the K-J method, and most salts show promising detonation performances ( D : 6699–8231 m s −1 , P : 19.2–30.7 GPa), among which the salt of 1-amino-1,2,3-triazolium trinitrophloroglucinate has a detonation properties comparable to RDX. The sensitivities results provided the salts as insensitive energetic materials. [ABSTRACT FROM AUTHOR]

A series of new nitrogen-rich energetic salts containing 1 H ,1′ H -[5,5′-bitetrazole]-1,1′-diol (BTO) anion and ethane-1,2-diaminium ( 1 ), 1-amino-1 H -1,2,3-triazol-3-ium ( 2 ), 4-amino-4 H -1,2,4-triazol-1-ium ( 3 ) and 4,5-diamino-4 H -1,2,4-triazol-1-ium ( 4 ) cations were synthesized by direct salt formation or by metathesis strategy. The structures of energetic salts 1 - 4 were comprehensively characterized by elemental analysis, mass spectrometry, IR and NMR spectroscopies and by X-ray crystallography. DSC and TGA methods were used to study thermal properties of these salts. Additionally, the non-isothermal kinetic parameters and thermodynamic parameters were calculated by utilizing the Kissinger's and Ozawa-Doyle's methods. The enthalpies of formation for all target compounds in this study were calculated, and their sensitivity to mechanical impact and friction was tested according to BAM guidelines. We found these new energetic salts exhibit good thermal stability and have typical decomposition temperatures above 230 °C, except for the salt 2 . All our salts have highly-positive enthalpies of formation (311.1–473.6 kJ mol − 1 ) and are insensitive to impact and friction stimuli (>40 J, 120 N). With a high nitrogen-rich content, high enthalpy of formation, good thermostability and very low sensitivity to impact, some of these new salts may have a potential for application in the field of environmentally friendly insensitive energetic materials. [ABSTRACT FROM AUTHOR]

The anti-cancerous activity of 6-gingerol extracted from Tongling White Ginger was investigated. 6-Gingerol inhibited the growth of HeLa cells with IC50 (96.32 μM) and IC80 (133.01 μM) and led to morphological changes, induced the cell cycle arrest in G0/G1-phase and ultimately resulted into apoptosis. Among cell cycle-related genes and proteins, the expression of cyclin (A, D1, E1) reduced, while of CDK-1, p21 and p27 showed slight decrease, except cyclin B1 and E1 (protein). Western blotting reported the induction of apoptosis with an increased Bax/Bcl-2 ratio, release of cytochrome c, cleavage of caspase-3, -8, -9 and PRPP in treated cells. 6-Gingerol activated AMPK, but inhibited PI3K/AKT phosphorylation with reduced P70S6K expression and also suppressed the mTOR phosphorylation. 6-Gingerol with 5-FU and Ptx resulted in 83.2% and 52% inhibition respectively, this synergy have stimulated apoptosis proteins more efficiently as compared to 6-Gingerol alone (10.75%) under in vitro conditions. [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]

Magnesium azotetrazole-1,1'-dioxide (1) was first prepared and intensively characterized by single-crystal X-ray diffraction, IR spectroscopy, mass spectrometry, elemental analysis, and DSC measurements. The heat of formation was calculated using the atomization energy method based on quantum chemistry and the heat of detonation was also predicted. The NBO analysis was performed for inspecting charge distributions. The sensitivities towards impact and friction were tested using the BAM standard. The high detonation performance (5289 kJ·kg-1), good thermal stabilities (245.5 °C) and excellent insensitivity (39.2 J and >360 N) as well as clean decomposition products supports it of great interest as a promising candidate of green insensitive energetic materials. [ABSTRACT FROM AUTHOR]

The synthesis of cellulase in filamentous fungi can be triggered by several inducers. In this study, a bamboo-shoot shell pretreated with Pleurotus ostreatus could promote the formation of cellulases in Aspergillus niger . Further identification, including UPLC-TOF-MS, ultrafiltration, and FT-IR, denoted that the soluble inducer was not a traditional disaccharide but a type of modified lignin polymer. This revelation may result in incipient strategies to ameliorate cellulase productivity. [ABSTRACT FROM AUTHOR]

A reticular 3D energetic metal-organic framework, sodium 1,1′-dinitramino-5,5′-bistetrazolate was first synthesized and fully characterized by crystal X-ray diffraction, elemental analysis, mass spectrometry, IR spectroscopy, differential scanning calorimetry (DSC) and sensitivity test. It shows a density of 1.892 g·cm −3 , a positive oxygen balance and a high decomposition temperature of 250 °C. The promising energetic properties were also investigated by using theoretical calculation methods. Its calculated heat of formation (529.5 kJ·mol −1 ) combined with impressive heat of detonation (5080 kJ·kg −1 ), good thermal stabilities and clean detonation products make it a competitive replacement as a green energetic material. [ABSTRACT FROM AUTHOR]

Co-culturing microorganism to degrade lignocellulose has been adapted by various researchers globally. The decomposition of bamboo-shoot shell powder (BSSP) by a two-fungus ( Pleurotus ostreatus and Aspergillus niger ) together was examined. During the degradation, there was a rise in the activities of enzymes carboxymethylcellulase (catalyzing cellulose degradation by the hydrolysis of β -1, 4 glycosidic bonds in cellulosic materials) and laccase (phenol oxidase catalyzing lignin degradation) responsible for metabolism of lignocellulosic material resulting into decrease in acid detergent fiber and lignin contents of BSPP. In addition, the physical properties of the shell fiber were changed from smooth and flexible to rough and crisp. The products of the decomposing fiber were complex, and most of them contained methyl or ethyl groups. The fungi decomposed native silicon compounds simultaneously during biodegradation. The net result of decomposition was a decrease in biomass as well as production of carboxymethylcellulase and laccase, two biotechnologically relevant extracellular enzymes with multiple industrial uses. [ABSTRACT FROM AUTHOR]

The features of Coriolis mass flow sensor output signal are analyzed, and a mathematical model of the time difference for the signals is built to evaluate the rationality and limitation of the proposed correction method when Coriolis mass flowmeter (CMF) is used to measure the gas-liquid two-phase flow. According to the experimental data of Coriolis mass flow sensor output signals under the gas-liquid two-phase flow condition, the time differences of the sensor output signals are extracted as a characteristic quantity to obtain the time difference sequence by adopting a digital zero-crossing detection method. The distribution pattern of the time difference sequence is analyzed with the probability density function, and the mathematical model of the time difference sequence is built by the correlation analysis. The mathematical model consists of a stable component and a fluctuating component. Correcting the stable component can improve the measurement accuracy of cumulative mass flow rate, and reducing the fluctuating component can enhance the measurement stability of instantaneous mass flow rate. Although the stable component cannot be completely corrected because its variation is nonlinear with the flow rate and drop in density, and the fluctuating component can only be reduced to a certain extent due to the real-time processing limitation of the instrument, CMF can provide relatively reliable measurement results of the liquid mass flow rate when the gas-liquid two-phase flow occurs. [ABSTRACT FROM AUTHOR]

The sequential extraction of peony seed dreg polysaccharides (PSDP) with hot buffer (HBSS), chelating agent (CHSS), dilute alkaline (DASS) and concentrated alkaline (CASS) yielded four different polysaccharide fractions. Based on their absorptions at 3600–3200 cm −1 and 1200–800 cm −1 , these fractions were confirmed to be polysaccharides. The properties of four PSDPs displayed some slight differences. The CASS showed the highest peak temperature and endothermic enthalpy. The emulsifying activity and emulsifying stability of four PSDPs exhibited a dose-dependent pattern; HBSS showed the highest emulsifying activity, and CHSS displayed the longest emulsifying stability. The four PSDPs also exhibited wide variations in their antioxidant activities. For example, i) CASS showed the highest DPPH radical scavenging activity, reducing power and ABTS radical scavenging activity; ii) HBSS exhibited the highest hydroxyl radical scavenging activity, and iii) CHSS displayed the higher ferrous ions chelating ability than others. [ABSTRACT FROM AUTHOR]

The peony seed dreg polysaccharides (PSDPs) were sequentially extracted using hot buffer (HBSS), chelating agent (CHSS), dilute alkaline (DASS) and concentrated alkaline (CASS). The rheological properties of PSDPs were investigated by steady-shear and oscillatory rheological measurements. The four PSDPs fractions in solution exhibited typical non-Newtonian and shear-thinning behavior. The viscosity of HBSS was higher than the rest. While the viscosity value of all PSDPs solution decreased at acid pH (4.0) and alkaline pH (10.0), in the presence of Ca 2+ and high temperature (90 °C), it increased in the presence of Na + and following freezing. The modulus G’ and G” of all PSDPs solution were increased with increasing oscillation frequency ranging between 0.01 and 100 Hz at each concentration. In all four cases, the crossover of G’ and G” values decreased gradually with increasing concentration of samples. [ABSTRACT FROM AUTHOR]

The ten-coordinate complex, (HATr)[Na(DNMz)] ·H2O ( 1) was synthesized by reaction of 5-(dinitromethylene)-4,5-dihydro-1 H-tetrazole (DNMz), sodium hydroxide, and 3-hydrazinium-4-amino-1,2,4-1 H-triazolium dichloride (HATr) in aqueous solution and characterized by various physico-chemical techniques. Complex 1 is an energetic material with a nitrogen content of 51.2 % and a decomposition temperature of 128.9 °C. The molecular structure of complex 1 crystallizes in the monoclinic system with P2(1)/ c group and shows an infinite 1D chain structure. The heat of formation was determined as -122.27 kJ ·mol-1 by using bomb calorimetry. In addition, the kinetic parameters were studied by Kissinger's and Ozawa-Doyle's methods. [ABSTRACT FROM AUTHOR]

Several novel nitrogen-rich salts of 3-hydrazino-4-amino-1,2,4-triazole (HATr) were synthesized by means of metathesis reactions or Brønsted acid–base reactions in this work. These nitrogen-rich salts were fully characterized by means of single-crystal X-ray diffraction, elemental analysis, and infrared. Their structures showed that the extensive hydrogen bonding interactions between the cations and anions formed a complex 3D network, which contributes to the high density of the salts. Some of these salts exhibited reasonable thermal stability (Td = 168–266 °C) and good impact sensitivities (IS = 4–40 J). In addition, the detonation pressures and velocities of the energetic salts were calculated, ranging from 23.1 GPa to 32.3 GPa and 7421 m s−1 to 8455 m s−1, respectively. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Two new ionic complexes, (DATr)2[Li2(TNR)2·2H2O]·2H2O (1) and (DATr)[Zn(DATr)Cl3] (2), were synthesized by using 3,4-diamino-1,2,4-triazole (DATr) as outer cation. X-ray single-crystal diffraction analysis revealed that the two complexes crystallize in triclinic and orthorhombic crystal systems, respectively. Differential scanning calorimetry was applied to assess the thermal decomposition behavior and kinetic parameters of decomposition were studied by using Kissinger’s and Ozawa–Doyle’s methods. Furthermore, the critical temperature of thermal explosion and parameters of thermodynamics were obtained. [ABSTRACT FROM PUBLISHER]

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]

Two novel energetic nitrogen-rich compounds 1,4-diaminotetrazol-5-one (DATO) and 1,4-dinitrotetrazol-5-one (DNTO) were proposed first and studied by quantum chemistry method with B3LYP/6-31G* level of theory. The optimized geometry, IR predicted spectrum and thermochemical parameters, frontier molecular orbitals and molecular electrostatic potential were calculated for inspecting the electronic structure, molecular stability and chemical reactivity. The important macroscopic properties including density, enthalpy of formation, detonation parameters and impact sensitivity have been predicted as well. As a result, two designed compounds DATO and DNTO possess positive enthalpy of formation (395.79 and 342.77 kJ/mol), impressive detonation parameters (D= 8.80 km/s, P = 33.69 GPa; D= 8.89 km/s, P = 34.98 GPa) superior to the remarkable explosive RDX, acceptable sensitivities and might be promising candidates of energetic materials. [ABSTRACT FROM AUTHOR]

[Display omitted] • Phospholipids were extracted from peony seed meal dreg. • Special ratio of phospholipid fraction content was observed in peony seed phospholipids. • Peony seed phospholipids were enriched in polyunsaturated fatty acids. • Emulsions formed with peony seed phospholipids had appreciable stability. • Peony seed phospholipids improved the antioxidant properties of resulting emulsions. Peony seed phospholipids (PPLs), a kind of multifunctional plant-like phospholipids were extracted from peony seed meal. We investigated the functional properties of PPLs and compared their emulsification performance in corn oil-peony seed oil o/w emulsion systems with that of soy lecithin (DPLs). The PPLs were characterized with the higher content of phosphatidylcholine (PC) (416 ± 28 mg/g) and lyso-phosphatidylcholine (LPC) (43 ± 14 mg/g) fractions, and lower content of phosphatidylethanolamine (PE) (71 ± 13 mg/g). The polyunsaturated fatty acids showed higher content (83.25%), with the highest content of linoleic acid (46.05%) in PPLs. PPLs-emulsions showed smaller average particle size and higher loaded peony seed oil content at pH 5, temperature 50 °C, and about 60% corn oil content. PPLs-emulsions imparted better hydroxyl radical scavenging efficiency and reducing power than DPLs. Our results suggest that PPLs can be used as emulsifiers with improved antioxidant properties. [ABSTRACT FROM AUTHOR]

1,5-Daminotetrazole (DAT) is of much interest because of the practical significance and the diversity of characteristics. The study on the decomposition pathway and the kinetics of DAT has been performed based on the quantum chemistry theory. The minimum energy path (MEP) calculation has shown that NH2N3 and NH2CN are the initially detected products of DAT. And the structures of reactant, products and transition state were optimized with MP2 methods using 6-311G** basis sets, and the energies were refined using CCSD(T)/6-311G** levels of theory. The calculated rate constants were obtained using the conventional transition-state theory (TST) and the canonical variational transition-state theory (CVT) methods. The calculation results indicated that the energy barrier of decomposition reaction is 47.98 kcal mol−1 and the variational effect is small. In addition, the rate constants and the Arrhenius experience formula of DAT decomposition have been obtained between 200 and 2500 K temperature regions. The fitted three-parameter expressions calculated using the TST and CVT methods are [ABSTRACT FROM AUTHOR]

A series of zero- to two-dimensional Cd(II) coordination compounds have been synthesized by the reaction of Cd(II) salts and 3-hydrazino-4-amino-1,2,4-triazole di-hydrochloride (HATr·2HCl). [CdCl 2 (HATr) 2 ] ( 1 ) and [Cd 2 Cl 4 (HATr) 2 (H 2 O) 2 ] ( 2 ) have discrete mononuclear and binuclear structures, respectively. [Cd(HATr) 2 (ClO 4 ) 2 ] n ( 3 ) presents polymeric 1-D chain and [Cd 2 (NO 3 ) 2 Cl 2 (HATr) 2 ] n ( 4 ) shows 2-D frameworks. All Cd(II) ions exhibit distorted octahedral configurations in 1 – 3, whilst both hexa and heptacoordinated Cd(II) are formed in 4 . The HATr ligands adopt chelating coordinated mode in 1 , while tri-dentate bridging–chelating mode in 2–4 . The chloride ion is a mono-coordinated ligand in 1 and 2 , but it bridges two adjacent metal ions in 4 . Furthermore, thermal behaviors have been investigated and the results reveal that all complexes have good thermal stability. The impact sensitivity test indicates that complex 3 is sensitive to impact stimuli. [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]

The hybrid DFT calculations with B3LYP/6-311G* level of theory have allowed us to gain insight into the azido-cyclization of 4,5-diazido-1,2,3-triazole and 3,5-diazido-1,2,4-triazole and the effect of solvent. The optimized geometry, charges and molecular electrostatic potential were calculated and the results indicate that the cyclization occurs mainly in the conversion azido → tetrazole, in which the molecular and electronic structures change more significantly. Further analysis of the energy parameters indicates that all possible reactions are endothermic and not spontaneous in the gas phase, but the first and second azido-cyclization of 3,5-diazido-1,2,4-triazole could be performed theoretically with energy barriers of 26 kcal mol−1 and 33 kcal mol−1. Again, the rate constants and the Arrhenius experience formula of azido-cyclization have been obtained between 200–1000 K temperature regions. In addition, the solvent effect on azido-cyclization was studied with acetone, trifluoroacetic acid and dimethylsulfoxide. The results show that the solvent effect can make the intermediates and products more stable than in the gas phase. The energy barriers for the first and second cyclization are lowered more or less especially in dimethylsulfoxide, and the influence on the azido-cyclization of 4,5-diazido-1,2,3-triazole is a little larger. [ABSTRACT FROM AUTHOR]

Melanotic neuroectodermal tumor of infancy is a rare melanin-containing neoplasm with locally aggressive and rapid expansile growth, usually involving the maxilla, skull, and mandible of early infancy. Radical surgery is critical for a long-term outcome. We present a case of 14-month-old girl with rapid-growing subcutaneous mass arising in the right temporal bone and extending intracranially on computed tomographic scan. Radical surgery was performed. A brownish-black tumor composed of large pigmented epithelioid cells, positive for cytokeratins and HMB-45, and nests of small neuroblast-like cells positive for neuron-specific enolase and synaptophysin, was diagnosed as melanotic neuroectodermal tumor of infancy. The patient remained well without evidence of recurrence for 1 year after surgery. Clinicopathological features, management alternatives and outcome were discussed. [ABSTRACT FROM PUBLISHER]

Bimetallic amidoboranes (MM′AB, M and M′ denote different metals, respectively) are capable of improving the efficiency of dehydrogenation process and purity of released hydrogen compared to monometallic amidoboranes. In order to elucidate the reason behind this improvement, we perform a solid state Density Functional Theory (DFT) study on several bimetallic amidoboranes recently synthesized, NaMg(NH 2 BH 3 ) 3 (SMAB), Na 2 Mg(NH 2 BH 3 ) 4 (DSMAB), Na[Li(NH 2 BH 3 ) 2 ] (SLAB), and K 2 Mg(NH 2 BH 3 ) 4 (DKMAB). Whereas the crystal structure SMAB has not been obtained yet (the other three have been obtained experimentally), we apply the Monte Carlo method to simulate its crystal structure. Then the optimized crystal structures and electronic structures of MM′ABs have been determined for further studies of their thermodynamic properties and the initial dehydrogenation mechanisms. Two metals in MM’AB play totally different roles to improve the appearance of dehydrogenation. Moreover, the first dihydrogen bond of N–H δ+ … −δ H–B prefers being formed between two neighboring [NH 2 BH 3 ] groups rather than in the same [NH 2 BH 3 ] molecule. The molecular dynamic study of the hydrogen diffusion at room temperature shows that H(B) atoms have faster speed than that of H(N) atoms caused by the bond strength and electronic structures. Generally, the diffusion rate of hydrogen is as the sequence of SMAB > SLAB > DKMAB > DSMAB. [ABSTRACT FROM AUTHOR]

Dysembryoplastic neuroepithelial tumors are rare, surgically curable, neuronal-glial neoplasms affecting young patients with intractable epilepsy. Its recognition is needed to avoid unnecessary adjuvant therapy. The authors reviewed the records of 15 patients with dysembryoplastic neuroepithelial tumors who underwent epilepsy surgery using intraoperative electrocorticography monitoring, including 8 males and 7 females (mean age, 15.8 years). Neuroimaging showed a predominantly intracortical location, the presence of septations, a triangular pattern of distribution, a lack of contrast enhancement, and an absence of peritumoral edema. Eleven cases were classified as complex type, 3 as simple type, and 1 as “nonspecific” type. Associated cortical dysplasia was found in 5 cases and leptomeningeal involvement in 1 case. Its immunophenotype suggested a pluripotential neuroepithelial origin. The mean follow-up was 37.5 months; 2 patients had tumor recurrence. Although they are generally benign neoplasms, recurrences sometimes occur. Complete resection of the tumor with the epileptogenic zone is important for a favorable outcome. [ABSTRACT FROM PUBLISHER]

Four eco-friendly energetic metal complexes of 3,4-diamino-1,2,4-triazole (DATr), including manganese (1), cobalt (2), nickel (3), and zinc (4), were synthesized by reacting DATr·HCl with the corresponding metal (Mn(II), Co(II), Ni(II), and Zn(II)) nitrate in aqueous solution and characterized by using Fourier transform-infrared spectroscopy and elemental analyses. The single crystals of2,3, and4were obtained and determined by X-ray single-crystal diffraction analysis. All three complexes crystallize in themonocliniccrystal system and belong toP2(1)/nspace group. The thermal decomposition processes were investigated by differential scanning calorimeter (DSC) and thermogravimetry–derivative thermogravimetry analyses. The results show that the decomposition temperatures of1–4are above 260 °C, depending upon their onset DSC peaks. It can be predicted that these complexes based on 3,4-diamino-1,2,4-triazole have good thermal stability. The nonisothermal kinetic parameters of decomposition were calculated by using Kissinger and Ozawa–Doyle’s methods. Furthermore, the sensitivities of these complexes to impact, friction, and flame were determined. Sensitivity tests revealed that2was more sensitive to external stimuli compared to the other three complexes. Four nitrate-containing metal complexes based on 3,4-diamino-1,2,4-triazole are described as eco-friendly energetic coordination compounds. Their synthesis, characterization, and some energetic properties are studied. The figure reveals the crystal structure of zinc (II) complex and also suggests the coordination mode of metal complexes. [ABSTRACT FROM PUBLISHER]

ABSTRACT Dispersion-flattened highly nonlinear (DF-HNL) photonic crystal fibers are useful for ultrafast optical signal processing. In this article, 100 Gbit/s-to-10 Gbit/s optical time demultiplexing with simultaneous 1-to-4 wavelength multicasting is successfully demonstrated by use of the cascaded four-wave mixing (FWM) in a 50 m DF-HNL photonic crystal fiber, for the first time. This scheme uses a single control-pulse light source only and a simple architecture. The wavelength multicasting of the time-demultiplexed optical signal is achieved on four wavelength channels of which two can have the minimum power penalty of 3.2 dB at 10−9 bit error rate compared to the 10 Gbit/s back-to-back measurement. With the cascaded FWM, our proposed scheme can be used to improve the functionality of ultrahigh-speed optical time-division multiplexed systems/networks so as to support wavelength multicasting applications in a cost-effective manner. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:2330-2335, 2014 [ABSTRACT FROM AUTHOR]

Nitrophenol energetic ionic salts based on the 5,6,7,8-tetrahydrotetrazolo[1,5- b][1,2,4]triazine (TZTN, 1) cation and nitrophenol anions have been synthesized in high yields by neutralization reactions. All the salts were characterized by X-ray single-crystal diffraction technology, IR spectroscopy, elemental analysis, and DSC measurements. The heats of formation of 2- 4 were calculated by using isodesmic reactions. The calculated detonation pressures of these salts range from 29.7 to 32.6 GPa and their detonation velocities fall between 8337 and 8613 m s-1; these properties make them competitive energetic materials. In addition, the sensitivities towards impact, friction, and flame were tested, and the results indicated that salts 2 and 3 have acceptable sensitivities, whereas salt 4 shows relatively high sensitivity towards impact and flame. [ABSTRACT FROM AUTHOR]

Response surface methodology (RSM) was applied to optimize the parameters of pectin extraction from okra pods. The extracted okra pectin was then investigated by steady-shear and oscillatory rheological measurements. Statistical analysis showed that the linear term of the liquid–solid ratio, the quadratic term of the pH, and the linear term of the extraction time showed highly significant effects on pectin yield. The optimal extraction conditions that maximized the pectin yield within the experimental range of the variables researched were a pH of 3.9, an extraction time of 64 min, an extraction temperature of 60 °C, and a liquid–solid ratio of 42:1. Under these conditions, the pectin yield was predicted to be 2.71%. At a liquid–solid ratio less than 2.5% w/w in aqueous solution, the pectin extracted from okra presented non-Newtonian shear-thinning behavior and could be well described by the Cross model. The okra pectin showed predominantly viscous responses ( G ′ < G ″) over a wide range of frequencies (10 −1 –10 Hz) at 20% strain. [ABSTRACT FROM AUTHOR]

The single crystal structure of 1,1′-bis (3,5-dimethyl-pyrazole) methenehydrazine (BDM) was determined by X-ray single crystal diffraction for the first time. The obtained experimental results indicated that BDM was the of 3,6-bis(3,5-dimethylpyrazol-1-yl)-1,4-dihydro-1,2,4,5-tetrazine (BDT), which was the key precursor of s-tetrazine. By this evidence, the preparation mechanism of BDT was proved: At 318.15 K, triaminoguanidine and pentanedione reacted to achieve the (BDM) by molecular and ; when heated to 363.15 K, BDT was then generated by two molecules of BDM with reaction. Furthermore, the properties and also the non-isothermal kinetic parameters have been investigated in the present work. [ABSTRACT FROM AUTHOR]

All-optical wavelength conversion with multicasting is investigated in this paper, which is based on cross-phase modulation in a highly nonlinear fiber. With a pump-modulated light and only a single continuous-wave probe, wavelength multicasting is realized by appropriately controlling the powers of two beams. Our simulation work reveals that 10 multicast channels can be obtained with theirQfactors being larger than six, if both pump and probe powers are properly selected. These wavelength channels of multicasting are positioned around the central wavelength of the probe on the blue-shifted and red-shifted sides. The central wavelength and the channel spacing can be affected by the wavelengths of the probe and the pump. The wavelength multicasting technique studied in this paper is simpler and can offer more multicast channels than that based on four-wave mixing. [ABSTRACT FROM AUTHOR]

Activation of the cell surface receptor, c-Mpl, by the cytokine, thrombopoietin (TPO), underpins megakaryocyte and platelet production in mammals. In humans, mutations in c-Mpl have been identified as the molecular basis of Congenital Amegakaryocytic Thrombocytopenia (CAMT). Here, we show that CAMT-associated mutations in c-Mpl principally lead to defective receptor presentation on the cell surface. In contrast, one CAMT mutant c-Mpl, F104S, was expressed on the cell surface, but showed defective TPO binding and receptor activation. Using mutational analyses, we examined which residues adjacent to F104 within the membrane-distal cytokine receptor homology module (CRM) of c-Mpl comprise the TPO-binding epitope, revealing residues within the predicted Domain 1 E-F and A-B loops and Domain 2 F′-G′ loop as key TPO-binding determinants. These studies underscore the importance of the c-Mpl membrane-distal CRM to TPO-binding and suggest that mutations within this CRM that perturb TPO binding could give rise to CAMT. [ABSTRACT FROM AUTHOR]

Highlights: [•] The systematic study of its structure and electronic structure in gas and solid phase. [•] The gas phase structures indicate that Li+ cation and Na+ cation acts as very different roles in the dehydrogenation. [•] Potential energy curves of dehydrogenation were obtained by CCSD(T) method. [•] Obtained the dehydrogenation rates similar to the experimental values. [ABSTRACT FROM AUTHOR]

Highlights: [•] The systematic study of its structure and electronic structure in gas and solid phase. [•] The gas phase structures indicate that Mg2+ cation and Na+ cation acts as very different roles in the dehydrogenation. [•] Potential energy curves of dehydrogenation were obtained by CCSD(T) method. [•] Obtained the dehydrogenation rates similar to the experimental values. [ABSTRACT FROM AUTHOR]

In order to suppress the airwave noise in marine controlled-source electromagnetic (CSEM) data, we propose a 3D deconvolution (3DD) interferometry method with a synthetic aperture source and obtain the relative anomaly coefficient (RAC) of the EM field reflection responses to show the degree for suppressing the airwave. We analyze the potential of the proposed method for suppressing the airwave, and compare the proposed method with traditional methods in their effectiveness. A method to select synthetic source length is derived and the effect of the water depth on RAC is examined via numerical simulations. The results suggest that 3DD interferometry method with a synthetic source can effectively suppress the airwave and enhance the potential of marine CSEM to hydrocarbon exploration. [ABSTRACT FROM AUTHOR]

An asymmetric strategy is a constructive means to regulate the energy and properties of energetic materials. In this work, a series of asymmetric energetic compounds based on bi(1,2,4-triazole) were designed and synthesized, and the related structural features and performances were systematically investigated by NMR spectroscopy, FT-IR spectroscopy, MS, EA, and DSC for their impact on asymmetric functional groups. Among them, a single trinitromethyl group-modified energetic compound termed "TNBN" was confirmed by X-ray single-crystal diffraction analysis. Benefiting from the asymmetric trinitromethyl groups, the structure of TNBN showed a unique stacking pattern, and exhibited good detonation performance (8787 m s−1 and 31.1 GPa) and acceptable insensitivity to mechanical stimuli (IS = 30 J and FS = 288 N) compared with its similar symmetric counterparts. This work aids understanding of the structure–performance relationship of asymmetric energetic compounds and demonstrates that appropriate modulation of the asymmetric trinitromethyl group is an effective approach to achieve high-energy insensitive energetic materials. [ABSTRACT FROM AUTHOR]

The design of novel energetic compounds constitutes a pivotal research direction within the field of energetic materials. However, exploring the intricate relationship between their molecular structure and properties, in order to uncover their potential applications, remains a challenging endeavor. Therefore, employing multi-molecule assembly techniques to modulate the structure and performance of energetic materials holds immense significance. This approach enables the creation of a new generation of energetic materials, fueling research and development efforts in this field. In this study, a series of coordination compounds are synthesized by utilizing tetranitroethide (TNE) as an anion, which possesses a high nitrogen and oxygen content. The synthesis involves the synergistic modification between metal ions and small molecule ligands. Characterization of the obtained compounds is carried out using various techniques, including single crystal X-ray diffraction, IR spectroscopy, elemental analysis, and simultaneous TG–DSC analysis. Additionally, the energy of formation for these compounds is calculated using bomb calorimetry, based on the heat of combustion. The detonation performances of the compounds are determined through calculations using the EXPLO 5 software, and their sensitivities to external stimuli are evaluated. [ABSTRACT FROM AUTHOR]

Two energetic ionic salts DATr ·NTO ( 2) and DATr ·TNR ( 3) of 3,4-diamino-1,2,4-triazole (DATr) ( 1) were synthesized by reaction of 3,4-diamino-1,2,4-triazole with either 3-nitro-1,2,4-triazole-5-one (NTO) or 2,4,6-trinitro-resorcinol (TNR) in aqueous solution. Their structures were characterized by FT IR spectroscopy (FT-IR) and X-ray single-crystal diffraction analysis. Their molecular structure and crystal structure were determined. They belong to the monoclinic crystal system, space group P21/ c. The crystal density is 1.693 g ·cm-3 and 1.738 g ·cm-3, respectively. The thermal decomposition characteristics of the title compounds were investigated using differential scanning calorimetry (DSC) and thermogravimetry/differential thermogravimetry (TG/DTG) technologies. Furthermore, the sensitivity properties were determined by standard methods. [ABSTRACT FROM AUTHOR]

The four-step dehydrogenation of lithium amidoborane dimer (LiNHBH) has been systematically simulated for the first time, and the respective rate constants have been calculated. Density functional theory has been used to optimize the molecular structure and ab initio direct kinetic theory has been applied to identify dehydrogenation mechanisms. The transition states were confirmed by intrinsic reaction coordinate calculations to insure the validity of our simulation and the barrier associated with each reaction was calculated. The Arrhenius equations of the four-step reactions (two pathways in all) were then obtained. The result indicated the dissociation maybe dimer way different from the traditional views. Our study has indicated a lower activation energy for dehydrogenation of the dimer compared to that of the monomer. The simulation is consistent with experimental observation because each step of the process requires increasingly higher energy. The study provides useful information on the properties and dehydrogenation mechanisms of metal-amidoborane compounds. [ABSTRACT FROM AUTHOR]