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Porous carbons derived from one-pot carbonization and activation of wood sawdust in a molten salt (LiCl-KCl) medium were employed for Hg0 removal. The carbons derived from molten salt carbonization (MSC) displayed much superior Hg0 removal performance comparing with the carbons derived from N2 pyrolysis method (NC). The best molar ratio of LiCl-KCl was 59:41, the optimal molten salt temperature was 700 °C, and the best mass ratio of wood sawdust to molten salt was 1:10. The MSC displayed good applicability at 50–125 °C. The saturation Hg0 adsorption capacity of MSC was about 7828.39 μg·g−1, far exceeding those for carbonaceous adsorbents reported in literatures. A Hg0 removal mechanism over MSC was proposed, i.e., the hierarchical porous structure accelerated mass transfer of Hg0, and the C O groups served as electron acceptors from Hg0 atoms to form organic matter bonded mercury (Hg-OM). The molten salt could be easily separated from the mixture of MSC for recycling multiple times. Thus, molten salt carbonization method appears to be promising in one-pot carbonization and activation of biomass as efficient adsorbents for gaseous Hg0.

A “molecular cage” was possibly built in glucose alkaline solution to limit the chemical reaction in a tiny space to control the size and morphology of HA nanoparticles. A possible reaction mechanism of HA nanoparticles confined space synthesis was proposed in this work. The super-small HA nanoparticles were successfully obtained in the first time in mild and green condition which had a 7 nm diameter. The adsorptions to Pb2+, Zn2+, Ni2+, Cd2+ ions in their mixture solution by the synthesized HA nanoparticles were studied. The adsorbent showed huge adsorption capacities for the targets (Pb2+ = 3289 mg/g, Zn2+ = 3150 mg/g, Ni2+ = 3061 mg/g and Cd2+ = 2784 mg/g), which indicated an excellent performance of the synthesized nano material in water treatment. Freundlich equation analysis and SEM images of the adsorption products suggested multilayer adsorptions to the targets, and a new recrystalline type adsorption on the surface of the host was found. Some Ca atoms in HA nanoparticles were also found to be substituted by the heavy metallic elements in the initial stage of the adsorptions. The synthesized nano material exhibits better application prospect in wastewater treatment field for its easy synthesis, low-cost and environmental friendly properties.

Day and night PM 2.5 samples were collected at coastal and inland stations in a megacity in China. Temporal, spatial, and directional characteristics of PM 2.5 concentrations and compositions were investigated. Average PM 2.5 concentration was higher at inland (153.28 μg/m 3 ) than at coastal (114.46 μg/m 3 ). PM 2.5 were significantly influenced by season and site but insignificantly by diurnal pattern. Sources were quantified by a two-way and a newly developed three-way receptor models conducted using ME2. Secondary sulfate and SOC (SSS SN and VE presented higher fractions at inland. Higher SS&SOC, SN and CC&BB in winter might be attributed to intensive coal combustion for residential warming and to stable meteorological conditions.

To find the potential algicidal microorganisms and apply them to prevent and terminate harmful algal blooms (HABs), we isolated an actinomycete U3 from Mangrove, which had a potent algicidal effect on the harmful alga Heterosigma akashiwo. It could completely lyse the algal cells by producing active compounds, which were highly sensitive to high temperature and strong alkaline, but resistant to acid. One μg/mL of crude extract of the fermentation supernatant could kill 70% of H. akashiwo cells in 3 d. Unlike most of the other known algicidal Streptomyces, U3 showed strong ability of proliferation with the algal inclusion as the nutrient source. The washed mycelial pellets also gradually exhibited significant algicidal effect during the visible growth in the algal culture. It suggests that U3 could efficiently absorb nutrients from algal culture to support its growth and produce algicidal compounds that might cause the autophagy of algal cells. Therefore, applying U3, as a long-term and environmentally friendly bio-agent to control the harmful blooms of H. akashiwo, would be effective and promising. And the decrease of bioavailable DOM and increase of bio-refractory DOM during the algicidal process of U3 provided new insights into the ecological influence of algicial microorganisms on marine ecosystem.

Harmful algal blooms (HABs) could be deemed hazardous materials in aquatic environment. Alexandrium tamarense is a toxic HAB causing alga, which causes serious economic losses and health problems. In this study, the bacterium Deinococcus xianganeasis Y35 produced a new algicide, showing a high algicidal effect on A. tamarense. The algicidal compound was identified as deinoxanthin, a red pigment, based on high resolution mass spectrometry and NMR after the active compound was isolated and purified. Deinoxanthin exhibited an obvious inhibitory effect on algal growth, and showed algicidal activity against A. tamarense with an EC50 of 5.636 mu g/mL with 12 h treatment time. Based on the unique structure and characteristics of deinoxanthin, the content of reactive oxygen species (ROS) increased after 0.5 h exposure, the structure of organelles including chloroplasts and mitochondria were seriously damaged. All these results firstly confirmed that deinoxanthin as the efficient and eco-environmental algicidal compound has potential to be used for controlling harmful algal blooms through overproduction of ROS. (C) 2015 Elsevier B.V. All rights reserved.

Day and night PM

Toxicity of algicidal extracts from Mangrovimonas yunxiaonensis strain LY01 on Alexandrium tamarense were measured through studying the algicidal procedure, nuclear damage and transcription of related genes. Medium components were optimized to improve algicidal activity, and characteristics of algicidal extracts were determined. Transmission electron microscope analysis revealed that the cell structure was broken. Cell membrane integrity destruction and nuclear structure degradation were monitored using confocal laser scanning microscope, and the rbcS, hsp and proliferating cell nuclear antigen (PCNA) gene expressions were studied. Results showed that 1.0% tryptone, 0.4% glucose and 0.8% MgCl2 were the optimal nutrient sources. The algicidal extracts were heat and pH stable, non-protein and less than 1kD. Cell membrane and nuclear structure integrity were lost, and the transcription of the rbcS and PCNA genes were significantly inhibited and there was up-regulation of hsp gene expression during the exposure procedure. The algicidal extracts destroyed the cell membrane and nuclear structure integrity, inhibited related gene expression and, eventually, lead to the inhibition of algal growth. All the results may elaborate firstly the cell death process and nuclear damage in A. tamarense which was induced by algicidal extracts, and the algicidal extracts could be potentially used as bacterial control of HABs in future.

In this study, we prepared 3-aminopropyl-triethoxysilane (APTEOS) functionalized sodium alginate (SA) porous membrane adsorbent (APTEOS/SA) and tested its adsorption performance for removing of Cr(III) ions. The physico-chemical properties of the pristine and Cr(III) ions loaded APTEOS/SA were investigated by FT-IR, SEM-EDX, TG, AFM, and contact angle goniometer methods. To investigate the adsorption kinetics of Cr(III) ions onto this newly developed APTEOS/SA, we performed a batch of experiments under different adsorption conditions: solution pH, adsorbent dose, initial Cr(III) ion concentration, adsorption temperature, and contact time. The APTEOS/SA exhibited an encouraging uptake capacity of 90.0mg/g under suitable adsorption conditions. To study the mechanism of adsorption process, we examined the Lagergren pseudo-first-order and pseudo-second-order kinetic model, the intra-particular diffusion model, and the Crank model. Kinetics experiments indicated that the pseudo-first-order model displayed the best correlation with adsorption kinetics data. The Crank model showed that the intra-particle solute diffusion was the main rate-controlling step. Furthermore, our adsorption equilibrium data could be better described by the Freundlich equation. We also carried out consecutive adsorption-desorption experiments eight times to show that the APTEOS/SA has encouraging adsorption-desorption efficiencies. The results indicates that the prepared adsorbent is promising for using as an effective and economical adsorbent for Cr(III) ions removal.

The thermal behavior and decomposition reaction kinetics of 2-nitroimino-5-nitro-hexahydro-1,3,5-triazine (NNHT) were investigated by TG–DTG and DSC under atmospheric pressure and flowing nitrogen gas conditions. The results show that the thermal decomposition process of NNHT has two mass loss stages. The exothermic decomposition reaction mechanism obeys chemical reaction rule. The kinetic parameters of the reaction are Ea = 131.77 kJ mol−1, lg(A/s−1) = 12.56, respectively. The kinetic equation can be expressed as: d α / d t = 10 12.86 1 − α 3 / 2 e − 1.5849 × 10 4 / T . The critical temperature of thermal explosion of NNHT obtained from the peak temperature (Tp) is Tbp = 467.22 K. The entropy of activation (ΔS≠), enthalpy of activation (ΔH≠), and free energy of activation (ΔG≠) of the reaction are −7.978 J mol−1 K−1, 127.99 kJ mol−1 and 131.62 kJ mol−1, respectively.

The effects of pressure and triethyleneglycol dinitrate (TEGDN) content on the decomposition reaction mechanism and kinetics of the double-base (DB) gun propellant composed of mixed ester of TEGDN and nitroglycerin (NG), and nitrocellulose (NC) were investigated by high-pressure differential scanning calorimetry (PDSC). The results show that the high pressure can decrease the DSC peak temperature, increase the decomposition heat; with the increase in the content of TEGDN, the decomposition heat decreases below 2MPa and rises at 4MPa. The high pressure can change the decomposition reaction mechanism and the kinetics of the DB gun propellant under 0.1MPa; the high TEGDN content does not change the mechanism functions, and the kinetic equation has a little difference between the sample and the control propellant; the high pressure makes the critical temperature (T(be)) of thermal explosion of the sample decrease, while the high TEGDN content make it present a increasing trend, and the DB gun propellant containing high content of TEGDN has a better thermal stability.

Using a multi-temperature artificial ageing testing apparatus and a standard method of determining the effective centralite/stabilizer content, the effective centralite/stabilizer content for varying time period in propellants heated at 95 degrees C, 90 degrees C, 85 degrees C, 75 degrees C and 65 degrees C was measured. Bethelot's equation and Semenov's equation in the temperature range of 65-95 degrees C for 81 propellants were established. The safe storage life at 30 degrees C, kinetic parameters [the apparent activation energy (E) and the pre-exponential constant (A)] and isolife temperatures obtained from the established equations and the activation energy (E(alpha=0.5)) obtained by integral isoconversional non-linear method for 81 propellants: single-base gun propellants (DF-01-DF-16), double-base gun propellants (SF-01-SF-13), tri-base gun propellants (SG-01-SG-02), nitramine gun propellants (GSF-01-GSF-18), double-base propellants (ST-01-ST-13), and composite modified double-base propellants (GST-01-GST-19), were given. Information was obtained on the effective centralite/stabilizer consumption reaction and the kinetic compensation effect.

To investigate the ambient metal pollution at the offshore drilling platform in the Bo Sea, which few studies have focused on, PM2.5 samples were collected and ten heavy metals, as well as As, were analyzed. High concentration levels of metals were observed, and the heavy metal pollution was quite serious compared to air quality standards and other marine areas. Back trajectories and wind dependent and PCA analyses showed that the marine sources included ship traffic emissions and corrosive stainless steels from the equipment at the platform as well as industrial emissions from stainless steel production and coal combustion sources, which were transported from the surrounding mainland. Both contributed greatly to the ambient metallic particles at the offshore platform. The Hazard Index values of the metals, which were much less than 1, the Carcinogenic Risk data, which were lower than the EPA's acceptable range, and the fact that the metal concentrations did not the exceed the permissible exposure limits of OSHA, indicated that the health risks from the ambient metallic particles for the oil-drilling workers were not significant.

Studies of the non-isothermal decomposition of Pb(0.25)Ba(0.75)(TNR).H(2)O (TNR=2,4,6-trinitro-1,3-dihydroxy-benzene) were carried out by means of TG-DTA, DSC and IR techniques. The thermal decomposition mechanism and the associated kinetics have been investigated. The kinetic parameters were obtained from the analysis of the DSC curves by integral and differential methods. The most probable kinetic model function of the dehydration reaction of Pb(0.25)Ba(0.75)(TNR).H(2)O were suggested by comparison of the kinetic parameters.

This paper reports the fabrication of layered double hydroxide (LDH)/conductive polymer multilayer films by alternate assembly of exfoliated ZnAl-LDH nanosheets and polyaniline (PANI) on silicon wafer substrates using the layer-by-layer (LBL) deposition technology. UV–vis absorption spectroscopy indicates a stepwise and regular growth of the (LDH/PANI) n multilayer films upon increasing deposition cycles. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) demonstrate that the surfaces of the films are microscopy smooth and uniform with a thickness of 2 nm per bilayer. Furthermore, the resulting (LDH/PANI) n multilayer films possess high selectively response to ammonia at room temperature. The presence of LDH nanosheets plays a critical role on the gas sensing for the pure PANI film has very low response to ammonia. The LBL assembly process based on LDH combines the conducting polymer and nano-inorganic material, which provides opportunities to develop new inorganic–organic films for gas sensing.

The specific heat capacity (C(p)) of 37.2/44/16/2.2/0.2/0.4-GAP/CL-20/Al/N-100/PCA/auxiliaries mixture was determined with the continuous C(p) mode of microcalorimeter. The equation of C(p) with temperature was obtained. The standard molar heat capacity of GAP/CL-20/Al/N-100/PCA/auxiliaries mixture was 1.225 J mol(-1)K(-1) at 298.15K. With the help of the peak temperature (T(p)) from the non-isothermal DTG curves of the mixture at different heating rates (β), the apparent activation energy (E(k) and E(o)) and pre-exponential constant (A(K)) of thermal decomposition reaction obtained by Kissinger's method and Ozawa's method. Using density (ρ) and thermal conductivity (λ), the decomposition heat (Q(d), taking half-explosion heat), Zhang-Hu-Xie-Li's formula, the values (T(e0) and T(p0)) of T(e) and T(p) corresponding to β → 0, thermal explosion temperature (T(be) and T(bp)), adiabatic time-to-explosion (t(TIad)), 50% drop height (H(50)) of impact sensitivity, and critical temperature of hot-spot initiation (T(cr,hot spot)) of thermal explosion of the mixture were calculated. The following results of evaluating the thermal safety of the mixture were obtained: T(be) = 441.64K, T(bp) = 461.66 K, t(Tlad) = 78.0 s (n = 2), t(Tlad) = 74.87 s (n = 1), t(Tlad) = 71.85 s (n = 0), H(50) = 21.33 cm.

[H(2)N=C(NH(2))(2)](+)(FOX-7)(-)-G(FOX-7) was prepared by mixing FOX-7 and guanidinium chloride solution in potassium hydroxide solution. Its thermal decomposition was studied under the non-isothermal conditions with DSC and TG/DTG methods. The apparent activation energy (E) and pre-exponential constant (A) of the two exothermic decomposition stages were obtained by Kissinger's method and Ozawa's method, respectively. The critical temperature of thermal explosion (T(b)) was obtained as 201.72 degrees C. The specific heat capacity of G(FOX-7) was determined with Micro-DSC method and theoretical calculation method and the standard molar specific heat capacity is 282.025 J mol(-1) K(-1) at 298.15 K. Adiabatic time-to-explosion of G(FOX-7) was also calculated to be a certain value between 13.95 and 15.66 s.

A new high nitrogen compound hydrazine 3-nitro-1,2,4-triazol-5-one complex (HNTO) was prepared by the reaction of 3-nitro-1,2,4-triazol-5-one with hydrazine hydrate, and its structure was characterized by means of organic elemental analyzer, FT-IR, XRD, (13)C NMR and (15)N NMR. The non-isothermal reaction kinetics of the main exothermic decomposition reaction of HNTO was investigated by means of DSC. The thermodynamic properties of HNTO were calculated. The results showed that the formation of HNTO is achieved by proton transfer of N(4) atom, and it makes a higher nitrogen content and lower acidity. The reaction mechanism of HNTO is classified as nucleation and growth, and the mechanism function is Avramo-Erofeev equation with n=2/5. The kinetic parameters of the reaction are E(a)=195.29 kJ mol(-1), lg(A (s(-1)))=19.37, respectively. The kinetic equation can be expressed as: d(alpha)/d(t) = 10(18.97)(1 - alpha)[-ln(1 - alpha)](3/5) e(-2.35 x 10(4)/T). The safety performances of HNTO were carried out. The critical temperature of thermal explosion are 464.26 and 474.37 K, the adiabatic time-to-explosion is 262s, the impact sensitivity H(50)=45.7 cm, the friction sensitivity P=20% and the electrostatic spark sensitivity E(50)>5.4J (no ignition). It shows that HNTO has an insensitive nature as RDX and NTO, etc.

DNP, a nitramine, has been studied with regard to the kinetics and mechanism of thermal decomposition, using thermogravimetry (TG), differential thermal analysis (DTA), infrared (IR) spectroscopy, and differential scanning calorimetry (DSC). The IR spectra of DNP have also been recorded and the kinetics of thermolysis has been followed by non-isothermal TG. The activation energy of the solid-state process was determined using Flynn–Wall–Ozawa method. The actual reaction mechanism obeyed nucleation and growth model, Avramie Erofeev function (n = 1) with integral form G(α) = −ln(1 − α) (α = 0.10–0.65). Ea and A were determined to be 116.51 kJ/mol and 1010.52 s−1. The T/Jump FT-IR analysis showed that CH2O, NO2, and NO are produced in larger amounts than CO2 and HCN. The cleavage of the N–N and C–N bond appears to be the primary step in the thermolysis of DNP.