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To further explore the damage characteristics and impact response of the shaped charge to the solid rocket engine (SRE) in storage or transportation, protective armor was designed and the shelled charges model (SCM)/SRE with protective armor impacting by shaped charge tests were conducted. Air overpressures at 5 locations and axial acceleration caused by the explosion were measured, and the experimental results were compared with two air overpressure curves of propellant detonation obtained by related scholars. Afterwards, the finite element software AUTODYN was used to simulate the SCM impacted process and SRE detonation results. The penetration process and the formation cause of damage were analyzed. The detonation performance of TNT, reference propellant, and the propellant used in this experiment was compared. The axial acceleration caused by the explosion was also analyzed. By comprehensive comparison, the energy released by the detonation of this propellant is larger, and the HMX or Al particles contained in this propellant are more than the reference propellant, with a TNT equivalent of 1.168–1.196. Finally, advanced protection armor suggestions were proposed based on the theory of woven fabric rubber composite armor (WFRCA).

Objectives This study’s objective was to explore the possibility of clinical evaluation of digestive system’s cancer with or without AKI patients’ cardiac function measured by impedance cardiography (ICG, Bioz. Cardio Dynamics, USA); then, try to analyze the possible reason of cardiac function changing, and to approach the independent risk factors for it. Methods Patients who were admitted to the Fourth hospital of Hebei Medical University, China between May 1st, 2019 and February 15th, 2022 were involved. A total of 51 patients with digestive system’s cancer with AKI or without AKI (31 men and 20 women, mean age 61.1 ± 10.9 year) were evaluated to routine ICG. Of the total, 19 patients were assessed to both ultrasound cardiography (UCG) and ICG. Result There were significant positive correlation with the cardiac function parameters, such as cardiac output (CO), cardiac index (CI), stroke volume (SV), left cardiac work index (LCWI) and ejection fraction (EF), measured by ICG and UCG. The relationship was observed between COICG and COUCG (r = 0.707, P = 0.001); CIICG and CIUCG (r = 0.718, P = 0.001); SVICG and SVUCG (r = 0.837, P ICG and EFUCG (r = 0.540, P = 0.017). The cardiac function parameters measured by ICG were statistically significant between cancer with AKI and without AKI patients (P

In this paper, a novel nonlinear viscoelastic constitutive model is proposed to describe the mechanical behavior of a polymer matrix composite (HTPB propellant). The model is built upon two stress-dependent nonlinear functions within the hereditary integral formulation of viscoelasticity. After implementation into a finite element code, the proposed model is utilized to simulate the stress-strain responses of cyclically loaded HTPB propellant. The results show that the model is capable of capturing the main characteristics of the hysteresis loops during fatigue process and good quantitative agreement is found under circumstances that self-heating effect is not evident. This paper deepens the understanding of the nonlinear behaviors of composite propellant under cyclic loading.

Previous studies have showed that the apoptosis of vascular smooth muscle cells (VSMCs) underlies the mechanism of pathological calcifications in patients with chronic kidney disease (CKD). SET domain-containing protein 8 (SET8), as an efficient protein has been reported to modulate cell apoptosis in hepatocellular carcinoma cell, esophageal squamous cell and neuronal cell through regulating pathological processes, such as cell-cycle progression and transcription regulation. However, whether SET8 is involved in high phosphorus induced vascular calcification by mediating apoptosis remains undefined. Here, we reported that SET8 was located both in nucleus and cytoplasm, and significantly downregulated in calcification models. SET8 deficiency promoted the apoptosis of VSMCs, which was indicated by the increased Bax/Bcl-2 and cleaved caspase-3/total caspase-3 ratios. Mechanistically, PI3K/Akt pathway was mediated by SET8 and inhibition of PI3K/Akt signaling pathway by giving LY294002 or transfecting Akt phosphorylation inactivated mutation plasmid increased apoptosis and calcification. Akt phosphorylation constitutively activated mutation could reduce apoptosis and calcification of VSMCs. Furthermore, exogenous overexpression of SET8 could reverse the effect of PI3K/Akt inhibition on the apoptosis and calcification of VSMCs. In summary, our researches suggested that SET8 overexpression ameliorated high phosphorus induced calcification of vascular smooth muscle cells via activating PI3K/Akt mediated anti-apoptotic effects.

The study of constitutive model of composite solid propellant is an important basis for analyzing the structural integrity of propellant grains of the solid rocket motor. From the view of microscopic, composite solid propellant is composed of a large number of solid particles with various sizes embedded in the matrix. In this paper, based on the distribution of solid particles with different sizes and the failure strength of the particle-matrix interfaces, the damage evolution was assumed to obey the Weibull distribution function and power law distribution function, and the two statistical damage constitutive models were first established. Then, the model parameters were identified and validated through the uniaxial tensile tests data of HTPB propellant. Finally, the prediction abilities of the developed two models were compared. The results show that both of the two statistical damage models can describe the stress-strain curves of HTPB propellant well.

Batch experiments were conducted to study the ability of activated palm kernel husk carbon (APKHC) to adsorb Pb(II) ions from aqueous solutions. The effects of various operational parameters, such as temperature (25–55°C), pH (1.0–5.0), contact time (0–120 min), and adsorbent dose (0.5–3.5 g/L) were examined. The results suggested that the adsorption of Pb(II) is exothermic and strongly dependent on pH. The optimum pH for Pb(II) removal is 5.0. The Pb(II) uptake by APKHC was fast and reached an equilibrium in 80 min. The Pb(II) removal efficiency increased with increasing APKHC dosage up to 2.0 g/L, and then reached a plateau with approximately 97% of Pb(II) removed. Experimental data were fitted using Langmuir and Freundlich isotherms. The Pb(II) adsorption can be described well by the Langmuir model with a maximum monolayer uptake capacity of 98.04 mg/g. Kinetic study results suggested that the adsorption process proceeded according to the pseudo-second-order kinetic model. In short, APKHC can b...

The aim of this paper is to study the mechanical properties of HTPB (Hydroxyl-terminated polybutadiene) composite propellant under harsh conditions. It describes two tests involving uniaxial tensile tests of various strain rates (ranging from 0.0005 s-1 to 1.5 s-1), temperatures (ranging from 223 K to 343 K) and high-cycle fatigue tests under low-temperature (223 K, frequencies were set at 50, 100, 150 Hz) using DMA (Dynamic Mechanical Analyzer). To highlight the effect of small pre-strain on fatigue properties of HTPB propellant, quasi-static stretching was carried out before fatigue loading, and uniaxial tensile tests at constant strain rates were successively applied. The results reveal that flow stress of propellant increases with reduction in temperature and rise in strain rate, and the strain rate-temperature equivalence relationship could be described by TTSP (time-temperature superposition principle) incorporating a modified WLF equation. Moreover, the rate of performance degradations and damage accumulation of propellant during fatigue tests increased with increasing strain amplitude and loading frequencies, while initial quasi-static loading has a negative effect on fatigue properties by comparing stress-strain relations after fatigue tests., {"references":["Xu F, Aravas N, Sofronis P. Constitutive modeling of solid propellant materials with evolving microstructural damage (J). Journal of the Mechanics and Physics of Solids, 2008, 56(5): 2050-2073.","Xu J S, Chen X, Wang H L, et al. Thermo-damage-viscoelastic constitutive model of HTPB composite propellant (J). International Journal of Solids and Structures, 2014, 51(18): 3209-3217.","Park S W, Schapery R A. Methods of interconversion between linear viscoelastic material functions. Part I—A numerical method based on Prony series (J). International Journal of Solids and Structures, 1999, 36(11): 1653-1675.","Williams, Malcolm L., Robert F. Landel, and John D. Ferry. \"The temperature dependence of relaxation mechanisms in amorphous polymers and other glass-forming liquids.\" Journal of the American Chemical society 77.14 (1955): 3701-3707.","Xu Jin-sheng. Experimental and numerical research on thermo-viscoelastic constitutive model of composite propellant (D). Nanjing: Nanjing University of Science and Technology, 2013. (in Chinese)"]}

Coconut husk activated carbon (CHAC) was used as an adsorbent to remove hexavalent uranium (U(VI)) from aqueous solutions by adsorption. Batch experiments were conducted to investigate the effects of contact time, pH, initial U(VI) concentration, and adsorbent dosage on U(VI) adsorption. The adsorption process reached an equilibrium state after 150 min. The uptake of U(VI) was highly pH dependent, and the optimum adsorption was at near-neutral pH. High U(VI) removal efficiencies could be achieved by increasing CHAC dosages. The uranium adsorption capacity increased with increasing initial U(VI) concentrations. Above a certain point, any further increase in initial U(VI) concentration produced no significant change in uranium adsorption capacity. Langmuir and Freundlich models were employed to describe the adsorption isotherm of U(VI) by CHAC. The Langmuir model fitted the equilibrium data better than the Freundlich isotherm. The maximum U(VI) adsorption capacity of CHAC was 6.67 mg/g. Kinetics dat...

In this paper, the static and dynamic mechanical viscoelastic behavior of NEPE propellant are studied. Under static conditions, five samples were subjected to constant-strain-rate monotonic loading with five different loading rates at room temperature. The dynamic mechanical analysis was employed for measurements of temperature and frequency dependence of the NEPE propellant by mean of BOSE-DMA-ELF3200 in frequency range from 1Hz to 16Hz. And get the dynamic mechanics temperature spectrum In the low temperature region, a single relaxation is observed in loss modulus-temperature Curves, which is glass transition relaxation. The results showed that NEPE propellant showed rate dependence and the same mechanical properties in the lower temperature and higher frequency.

Two Co(II) complexes, [Co(INAIP)(dib)]·4H2O and [Co(INAIP)(phen)(H2O)]·H2O have been synthesized by the reaction of 5-(isonicotinamido)isophthalic acid (H2INAIP) and CoSO4·7H2O, as well as N-donor ligands, namely 1,4-di(1-imidazolyl)benzene (dib) and 1,10-phenanthroline (phen) under hydrothermal conditions. Single-crystal X-ray diffraction analysis indicates that [Co(INAIP)(dib)]·4H2O has a two-dimensional (2D) double-layer network structure with a (4, 4) topology, while [Co(INAIP)(phen)(H2O)]·H2O displays a one-dimensional chain structure, extending to a 2D net through the π–π interactions. In addition, the photoluminescence and degradation of methyl orange in a Fenton-like process using the complexes as catalysts were investigated.

Activated palm kernel shell carbon (APKSC) was used to remove U(VI) from aqueous solutions in a batch system. The adsorption kinetics, isotherms, and effects of various parameters, such as temperature, contact time, solution pH, adsorbent dosage, and initial U(VI) concentration on the U(VI) adsorption process were studied. Equilibrium was reached after 120 min in the range of studied U(VI) concentrations and temperatures. U(VI) uptake was insignificantly affected by temperature, but was highly pH dependent, and the optimum pH for removal was 5.5. U(VI) removal efficiency increased with the increasing adsorbent dosage. U(VI) sorption capacity increased with increasing initial U(VI) concentration; any further increases in initial U(VI) concentration above a certain point caused insignificant changes in U(VI) sorption capacity. Isotherm data could be described by the Langmuir isotherm model with a maximum U(VI) adsorption capacity of 51.81 mg/g. Kinetic data were fitted to pseudo-first-order and pseudo-second-order equations, which suggested that the U(VI) adsorption onto APKSC was better reproduced by the pseudo-second-order model rather than pseudo-first-order model. Our results indicated that APKSC might be used as a cheap adsorbent in the treatment of uranium-containing wastewater.

In the title compound, [Ni(C14H8N2O5)(H2O)2]n, the NiIIcation is six-coordinate with a slightly distorted octahedral coordination geometry and the 4-(isonicotinamido)phthalate ligand links the NiIIcentres into a three-dimensional structure withsratopology. The structure is also stabilized by N—H...O hydrogen bonding between the uncoordinated amide groups of the ligand and extensive O—H...O hydrogen bonding between the two coordinated water molecules. The magnetic and thermal stability properties of the title compound are also discussed.

Two Ni(II) metal–organic frameworks, [Ni(INAIP)(DMF)]·0.5DMF and [Ni(INAIP)(H2O)]·2H2O, have been synthesized by the reaction of 5-(isonicotinamido)isophthalic acid (H2INAIP) with NiSO4·6H2O using different reaction solvents. Single-crystal X-ray diffraction analysis indicates that [Ni(INAIP)(DMF)]·0.5DMF has a twofold interpenetrated three-dimensional (3D) framework with sra topology, while [Ni(INAIP)(H2O)]·2H2O has a two-dimensional (2D) network structure with a 4-connected (43·63) topology. In addition, the magnetic and adsorption properties of the complexes were explored.

In this paper, the modified magnetic chitosan resin containing diethylenetriamine functional groups (DETA-MCS) was used for the adsorption of uranium ions from aqueous solutions. The influence of experimental conditions such as contact time, pH value and initial uranium(VI) concentration was studied. The Langmuir, Freundlich, Sips and Dubinin–Radushkevich equations were used to check the fitting of adsorption data to the equilibrium isotherm. The best fit for U(VI) was obtained with the Sips model. Adsorption kinetics data were tested using pseudo-first-order and pseudo-second-order models. Kinetic studies showed that the adsorption followed the pseudo-second-order kinetic model, indicating that the chemical adsorption was the rate-limiting step. The present results suggest that DETA-MCS is an adsorbent for the efficient removal of uranium(VI) from aqueous solution.

Direct reduced iron (DRI), also called sponge iron, was used for the removal of U(VI) from aqueous solution. Batch experiments were conducted to evaluate the effect of various factors including contact time, solution pH, DRI dosage and initial uranium concentration on this removal process. The result suggested that U(VI) can be rapidly removed by DRI and this removal process followed an apparent first-order reaction kinetics. The optimum pH for uranium removal was between 2.0 and 4.0. Whether U(VI) can be fully removed was influenced by the molar ratio of DRI to U(VI) in solution. The aqueous U(VI) can be removed completely when this ratio was more than ca. 1,000. The U(VI) removal capacities of DRI decreased with increasing DRI dosages at a constant concentration of U(VI), but increased almost linearly with increasing initial U(VI) concentrations at a fixed dosage of DRI. The maximum U(VI) removal capacity was 5.71 mg/g DRI. Finally, the possible mechanism of U(VI) removal by DRI was also discussed. The XPS and XRD analysis showed that U(VI) was deposited as UO3 onto DRI surface, indicating that U(VI) can be removed without reduction.

This study presents the characterization of the nonlinearly viscoelastic behavior of double base propellant (DBP) using Schapery-type constitutive model in the different conditions of temperature, strain level and strain rate. A recursive-iterative numerical algorithm is generated for the Schapery-type nonlinearly viscoelastic constitutive and implemented in a displacement-based finite element (FE) code for ABAQUS user material subroutines. Then, the model parameters are obtained by analyzing the response of creep-recovery tests and constant rate tensile tests at different temperatures, strain levels and strain rates. And find a linear relationship between temperatures and the effective stresses which determine the limit of linear viscoelactic. The FE model with the calibrated time-dependent and nonlinear material parameters is used to simulate the creep-recovery tests and the constant rate tensile tests, and reasonable predictions are shown.

In the title compound, {[Co(C14H8N2O5)(C10H8N2)]·3H2O}n, the CoIIcation is five-coordinated with a slightly distorted trigonal–bipyramidal geometry, and the 5-isonicotinamidoisophthalate ligands link CoIIatoms into a layered structure. These two-dimensional arrays are further pillared by rod-like 4,4′-bipyridine ligands to give a three-dimensional framework with pcu (primitive cubic) topology. The magnetic and adsorption properties of the title compound are also discussed.

Using tetrabutyl titanate as the titanium source, and ammonia and ferric nitrate as the sources of nitrogen and ferrum respectively, iron and nitrogen-codoped nano-TiO2 gelatins were prepared by sol-gel method. The iron and nitrogen-codoped nano-TiO2 complex films were prepared with the obtained gelatins used to coat the surface of cleaned glass slides by several times of dipping-lifting procedure, followed by natural seasoning at room temperature and calcined at 450 degrees C for 3 hours, then the films were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), X-ray photoelectron spectrum (XPS) and ultraviolet-visible diffuse reflectance spectrum (UV-Vis). The XRD spectra o f samples showed that the Fe-TiO(2-x)Nx, filmswere of anatase structure with a few of oxygen atoms in the lattice of anatase TiO2 substituted by nitrogen atoms, resulting in the distortion of crystal lattice. The SEM image showed that the nanoparticles of the films have a good dispersion characteristic and uniform orbicular shape with an average diameter of about 19 nm. The absorption edges of UV-Vis spectra exhibited a red shift up to 740 nm when the TiO2 films were codoped with iron and nitrogen. The XPS of the Fe-TiO(2-x)Nx film presented a lowering of Ti 2p(3/2) electron binding energy because of the codoping of iron and nitrogen, which then resulted in the widening of the absorption of visible light range. The photocatalytic properties were studied by photocatalytical degradation of sudan I as a model reaction in a self-assembled light-reactor. When the atomic ratio of Fe3+/Ti4+ reached 0.4%, the Fe-TiO(2-x)Nx film showed the highest catalytic performance in degradation of sudan I which was decomposed by up to 97% after 4 hours of photocatalytic reaction. Codoping of nitrogen and appropriate amount of iron in TiO2 enhances photoresponse and utilizing efficiency in visible light region, and then improves the performances of Fe-TiO(2-x)Nx photocatalyst. The complex film catalyst prepared by this method will have potential application in areas of wastewater disposal.

In wireless sensor networks (WSNs), secure data aggregation is an important application. Previous works are implemented by authentication among neighboring sensors. Considering that in many cases, data aggregation is both spatial and temporal correlation, this paper proposes a distributed and localized secure data aggregation algorithm based on behavior trust (BTDA). The security and reliability of the algorithm are implemented by using statistical hypothesis test for matching the reading sequence of sensors and statistical characteristics of the data aggregation. Simulation shows the algorithm efficiently.

Comparative studies were carried out on GOD-trinder method for measuring glucose in serum with four different kinds of benzene-original phenols-phenyl hydroxide, 2,4-dichlorophenol, 2,6-dichlorophenol and resorcinol. It is shown that when the three coloring systems-phenyl hydroxide, 2,4-dichlorophenol or resorcinol coupling with glucose oxidase-peroxidase-4-a minoantipyrine-hydrogen peroxide (GOD-POD-4-AA-H2O2) respectively were used for clinical assay of glucose in serum, the determination results showed no significant differences (P0.05). Compared with phenyl hydroxide, the coloring system of 2,4-dichlorophenol is better in the aspects of sensitivity, precision and accuracy; the resorcinol system has lower sensitivity with the advantage of faster detecting velocity, and larger linear range, and can be used for on-line rapid analysis of samples with more concentrated glucose in industry.

A new method for direct determination of ammonia in plasmas with indophenol reagent is described. It is shown that using sodium citrate as anticoagulant in phosphate buffer within pH 10.5-11.2, indophenol reagent reacts sensitively with ammonia in the plasmas to form a stable blue compound with a maximum absorption at 630 nm with low interference. The apparent molor absorptivity is 2.48 x 10(4) L x mol(-1) cm(-1) , and the linear range 0-1500 micromol x L(-1) (r = 0.9999) with a detection limit of 1.7 micromol x L(-1). The relative standard deviation is 1.13% (n=11) and the recoveries are in the range of 93.6%-101.6% with an average recovery of 97. 0%. The proposed method has been applied to detect ammonia in the plasmas from 43 healthy persons and 97 patients who suffered from liver diseases with satisfactory results.

Nitrate and nitrite is one of important physical and chemical index in the analysis of environmental samples. A new catalytic spectrophotometric method for the determination of nitrate and nitrite has been established based on the catalytic action of nitrite on the oxidative fading reaction of methylene blue with potassium bromate in dilute phosphoric acid medium. The optimum experimental conditions were investigated in detail, including the selection of measuring wave-length and catalytic reactive medium, the dosage of indicator and oxidizer, the influence of temperature and reactive time, and the interference of co-existent ions with the assay. The results showed that, the linear responses of nitrite and nitrate are in the ranges of 0-200 and 0.003-310 micrograms.L-1 respectively. The method offers the advantages of simplicity, rapidity and sensitivity. It has been applied to analyse water samples with satisfactory results.

In the title compound, [Ho(C7H6NO2)3(H2O)]n, a two-dimensional coordination polymer, the eight-coordinate HoIII ions are bridged by two carboxyl­ate groups from two 4-amino­benzoate ligands, forming a centrosymmetric dinuclear block. These blocks are further connected by 4-amino­benzoate ligands, yielding a two-dimensional network; a three-dimensional supra­molecular structure is then formed via hydrogen bonds.

The title compound, [Cd(C8H6BrNO4S)(C12H8N2)(CH4O)], incorporating a Schiff base formed by amino­methane­sulfonic acid and 5-bromo­salicylaldehyde, was synthesized in a water–methanol solution. In the structure, the CdII atom is six-coordinated by one O atom from a methanol mol­ecule, two N atoms from a 1,10-phenanthroline ligand, and one N and two O atoms from the Schiff base in a distorted octa­hedral coordination geometry. A one-dimensional chain structure is formed via C—H⋯O hydrogen bonds.