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The high-temperature strain gauge is a sensor for strain measurement in high-temperature environments. The measurement results often have a certain divergence, so the uncertainty of the high-temperature strain gauge system is analyzed theoretically. Firstly, in the conducted research, a deterministic finite element analysis of the temperature field of the strain gauge is carried out using MATLAB software. Then, the primary sub-model method is used to model the system; an equivalent thermal load and force are loaded onto the model. The thermal response of the grid wire is calculated by the finite element method (FEM). Thermal-mechanical coupling analysis is carried out by ANSYS, and the MATLAB program is verified. Finally, the stochastic finite element method (SFEM) combined with the Monte Carlo method (MCM) is used to analyze the effects of the physical parameters, geometric parameters, and load uncertainties on the thermal response of the grid wire. The results show that the difference of temperature and strain calculated by ANSYS and MATLAB is 1.34% and 0.64%, respectively. The calculation program is accurate and effective. The primary sub-model method is suitable for the finite element modeling of strain gauge systems, and the number of elements is reduced effectively. The stochastic uncertainty analysis of the thermal response on the grid wire of a high-temperature strain gauge provides a theoretical basis for the dispersion of the measurement results of the strain gauge.

In view of the important position of crude oil in the national economy and its contribution to various economic sectors, crude oil price and volatility prediction have become an increasingly hot issue that is concerned by practitioners and researchers. In this paper, a new hybrid forecasting model based on variational mode decomposition (VMD) and kernel extreme learning machine (KELM) is proposed to forecast the daily prices and 7-day volatility of Brent and WTI crude oil. The KELM has the advantage of less time consuming and lower parameter-sensitivity, thus showing fine prediction ability. The effectiveness of VMD-KELM model is verified by a comparative study with other hybrid models and their single models. Except various commonly used evaluation criteria, a recently-developed multi-scale composite complexity synchronization (MCCS) statistic is also utilized to evaluate the synchrony degree between the predictive and the actual values. The empirical results verify that 1) KELM model holds better performance than ELM and BP in crude oil and volatility forecasting; 2) VMD-based model outperforms the EEMD-based model; 3) The developed VMD-KELM model exhibits great superiority compared with other popular models not only for crude oil price, but also for volatility prediction.

Purpose: We verified whether fetal RPE (fRPE) cells and mesenchymal stem cells (MSCs) cotransplantation can combine the features of these two cell types and alleviate retinal degeneration in a retinal degenerative disease mouse model., Methods: Tail vein injection of sodium iodate (NaIO3) was conducted to establish the retinal degenerative disease mouse model. MSCs and fRPE cells were transplanted either separately or combined in the subretinal space of retinal degenerative disease animals. ERG, optical coherence tomography, histologic, and immunofluorescence analyses were performed. Furthermore, the expression level of Crx, rhodopsin, Iba1, F4/80, Caspase 3, nerve growth factor, and brain-derived neurotrophic factor were assessed to investigate the mechanisms involved in cell transplantation effects., Results: Cotransplantation of fRPE and MSC cells promoted significant improvements in ERG results and in the survival rate of transplanted cells. In addition, MSC and fRPE cell cotransplantation resulted in an increase in the thickness of the total retina, as well as in the outer and inner nuclear layers. Combined transplantation also upregulated the expression level of Crx and rhodopsin and downregulated caspase 3 expression, highlighting its better photoreceptor rescue effect in relation to the single cell type transplantation. Finally, combined transplantation suppressed the expression of Iba1 and F4/80 factors while increasing the endogenous expression of nerve growth factor and brain-derived nerve growth factor neurotrophic factors. These data suggest that MSC and fRPE cell cotransplantation is able to suppress immunoreactions and promote neurotrophic factor excretion., Conclusions: Combined transplantation of MSCs and fRPE cells results in a better retinal rescue effect than single cell type transplantation in NaIO3-induced retinopathy.

This work was designed to explore the characteristics of photodegradation of herbicides in the copper-polluted water body. The results showed that Cu(II) alone could induce a photo Fenton-like reaction to enhance the degradation of atrazine, in which hydroxyl radical (*OH) was a main active species. Humic acids restrained atrazine degradation, nevertheless, when introducing Cu(II), the photodegradation was accelerated, in which singlet oxygen (1O2) replaced *OH acting as the prevailing species. A feasible mechanism for the photochemical process was also proposed, which is helpful for better understanding the environmental photochemistry of atrazine in the copper-polluted water.

Soil/air partition coefficients (K(SA)) were measured experimentally on a silty clay loam soil spiked with polychlorinated biphenyls (PCBs) over a wide range of environmentally relevant temperatures (-30 to +30 degrees C). Measured K(SA)-values ranged over 6.4 orders of magnitude, with log K(SA) from 4.3 for PCBs 10/4 at +30 degrees C to 10.7 for PCBs 77/110 at -30 degrees C. Higher than expected, K(SA)-values were observed at subzero temperatures (by up to one order of magnitude, at -30 degrees C). The plots of log K(SA) vs. reciprocal absolute temperature show a change in slope at 0 degrees C. A log-log linear regression of K(SA) vs. octanol/air partition coefficient (K(OA)) has a slope close to 1, indicating that K(OA) is a good descriptor of the interchemical variability in K(SA). Further study showed that K(OA)-based Karickhoff-type equations can perfectly fit experimental K(SA)-values.

Sorption of perfluorooctane sulfonate (PFOS) to oil and oil-derived black carbon (BC) from solutions varying in pH and [Ca(2+)] was investigated. Oil is a strong sorbent for PFOS, together with the independence of oil-water distribution coefficient (K(oil)) on solution parameters (pH values and [Ca(2+)]), suggesting that hydrophobic interactions of the hydrophobic moieties of PFOS with oil played a dominant role. BC sorption for PFOS is not stronger or more nonlinear than other natural organic carbon from solution in the case of 0.5mM [Ca(2+)] and pH 5.05, indicating that specific adsorption sites on BC were probably not fit for PFOS. However, both sorption capacity and nonlinearity of PFOS increased obviously with decreasing solution pH and increasing [Ca(2+)], resulting in the potential importance of BC at environmentally low PFOS level, from solution at high [Ca(2+)] or low pH. The role of BC in PFOS sorption was significantly influenced by environmental conditions and solute aqueous concentrations.

This research focused on immersion method synthesis of visible light active salicylic acid (SA)-modified TiO2 nanotube array electrode and its photoelectrocatalytic (PEC) activity. The SA-modified TiO2 nanotube array electrode was synthesized by immersing in SA solution with an anodized TiO2 nanotube array electrode. Scanning electron microscope (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), infrared spectroscopy (IR), UV-vis diffuse reflectance spectrum (DRS), and Surface photovoltage (SPV) were used to characterize this electrode. It was found that SA-modified TiO2 nanotube array electrode absorbed well into visible region and exhibited enhanced visible light PEC activity on the degradation of p-nitrophenol (PNP). The degradation efficiencies increased from 63 to 100% under UV light, and 79-100% under visible light (lambda>400 nm), compared with TiO2 nanotube array electrode. The enhanced PEC activity of SA-modified TiO2 nanotube array electrode was attributed to the amount of surface hydroxyl groups introduced by SA-modification and the extension of absorption wavelength range.

The soil/air partition coefficients (K(SA)) for two polycyclic aromatic carbons (PAHs) and six organochlorine pesticides (OCs) were determined by a solid-phase fugacity meter over a wide temperature range of -30 to +30 degrees C in a paddy field soil. Literature values for PAHs and OCs obtained by the same method were 1.9-5.1 times of present values at +20 degrees C. Experimentally determined K(SA) ranged over six orders of magnitude, with log K(SA) from 4.5 for alpha-hexachlorocyclohexane at +30 degrees C to 10.4 for trans-nonachlor at -20 degrees C. Separate linear regressions of log K(SA) and reciprocal absolute temperature were employed at temperatures above 0 degrees C and below 0 degrees C. The calculated enthalpies associated with the phase transfer from the soil to the air (DeltaH(SA)) over 0 to +30 degrees C range from 78 to 108 kJmol(-1), which are in a good agreement with the literature values.

Thermal remediation of the soil contaminated with crude oil using microwave heating enhanced by carbon fiber (CF) was explored. The contaminated soil was treated with 2.45 GHz microwave, and CF was added to improve the conversion of microwave energy into thermal energy to heat the soil. During microwave heating, the oil contaminant was removed from the soil matrix and recovered by a condensation system of ice-salt bath. The experimental results indicated that CF could efficiently enhance the microwave heating of soil even with relatively low-dose. With 0.1 wt.% CF, the soil could be heated to approximately 700 degrees C within 4 min using 800 W of microwave irradiation. Correspondingly, the contaminated soil could be highly cleaned up in a short time. Investigation of oil recovery showed that, during the remediation process, oil contaminant in the soil could be efficiently recovered without causing significant secondary pollution.

The solubility and sorption of oil by uncontaminated clay loam and silt loam soils were studied from water and cosolvent/water solutions using batch techniques. The data obtained from the dissolution and sorption experiments were used to evaluate the applicability of the cosolvent theory to oil as a complex mixture. Aqueous solubility and soil-water distribution coefficients (K(d,w), L/kg) were estimated by extrapolating from cosolvent data, with a log-linear cosolvency model, to the volume fraction of cosolvent (f(c)) 0, and were compared with direct aqueous measurements. The extrapolated water solubility was 3.16 mg/L, in good agreement with the directly measured value of 3.83 mg/L. Extrapolated values of K(d,w) for the two soils were close to each other but consistently higher than the values from direct aqueous measurements, because of the presence of dissolved organic carbon (DOC). The partition coefficient (K(DOC)) between the DOC and the freely dissolved phase and the OC-normalized sorption coefficient (K(OC)) were determined. The average values of logKD(OC) and logK(OC) were estimated as 4.34 and 3.32, respectively, giving insight into the possibility of oil becoming mobilized and/or of the soil being remedied. This study revealed that the cosolvency model can be applied to a broader range of hydrophobic organic chemicals (HOCs) than has been previously thought. The results aided in a reliable determination of water solubility and sorption coefficients and provide information about the fate of oil in solvent-contaminated environment.

Titanium dioxide (TiO2) nanotube film electrodes are fabricated by the anodic oxidation method. Scanning electron microscopy (SEM) showed that these tubes were well aligned and organized into high-density uniform arrays. XRD analysis showed the TiO2 nanotubes to be in the anatase crystal form. The TiO2 nanotube film electrode exhibited increased photoelectrocatalytic (PEC) capability compared to a traditional TiO2 film electrode fabricated using the anodizing method for pentachlorophenol (PCP) degradation in aqueous solution. The bias potential, pH value, and electrolyte concentration were shown to be important factors influencing the degradation of PCP by the PEC method using the TiO2 nanotube film electrode as the working electrode.

Catalytic wet air oxidation (CWAO) is a promising method for the treatment of heavily contaminated wastewater. However, its application is restricted due to severe operation conditions (high pressure and high temperature). A microwave (MW) assisted oxidation method was investigated aiming to treat heavily contaminated wastewater under milder conditions. H-acid (1-amino-8-naphthol-3, 6-disulfonic acid) was selected as target compound to evaluate the performance of this novel process. The removal of H-acid and TOC (total organic carbon) for H-acid solution of 3000 mg/L reached as high as 92.6% in 20 min and 84.2% in 60 min, respectively under optimal conditions. The existence of activated carbon and oxygen proved to be critical for effective treatment. The activated carbon acted not only as a catalyst for H-acid decomposition, but also as a special material for the absorption of MW energy. Air was supplied to the reactor as an oxygen source at constant flows. The amino group in H-acid was converted ultimately into nitrate, and sulfonic group into sulfate. This observation gave an evidence of H-acid mineralization although other organic intermediates were unable to be determined. The value of BOD(5)/COD (ratio of 5d biochemical oxygen demand to chemical oxygen demand) increased from 0.008 to 0.467 indicating a significant improvement of biodegradability for the solution, which is beneficial for the further biological treatment of the wastewater.

A microwave (MW) assisted oxidation process was investigated for degradation of p-nitrophenol (PNP) from aqueous solution. The process consisted of a granular activated carbon (GAC) fixed bed reactor, a MW source, solution and air supply system, and a heat exchanger. The process was operated in continuous flow mode. Air was applied for oxygen supply. GAC acted as a MW energy absorption material as well as the catalyst for PNP degradation. MW power, air flow, GAC dose, and influent flow proved to be major factors which influenced PNP degradation. The results showed that PNP was degraded effectively by this new process. Under a given condition (PNP concentration 1330mg/L, MW power 500 W, influent flow 6.4 mL/min, air flow 100 mL/min), PNP removed 90%, corresponding to 80% of TOC removal. The pathway of PNP degradation was deduced based on GC-MS identification of course products. PNP experienced sequential oxidation steps and mineralized ultimately. Nitro-group of PNP converted to nitrite and nitrate. Biodegradability of the solution was improved apparently after treatment by MW assisted oxidation process, which benefit to further treatment of the solution using biochemical method.

Biofiltration of an air stream containing p-xylene has been studied in a laboratory hybrid biofilter packed with a mixture of mature pig compost, forest soil and the packing material which was made of polyethylene (PE) and used in the moving bed biological reactor (MBBR) in wastewater treatment. Three flow rates, 9.17, 19.87 and 40.66 m(3)m(-2)h(-1), were investigated for p-xylene inlet concentration ranging from 0.1 to 3.3 g m(-3). A high elimination capacity of 80 g m(-3)h(-1) corresponding to removal efficiency of 96% was obtained at a flow rate of 9.17 m(3)m(-2)h(-1) (empty bed residence time of 132 s). At a flow rate of 40.66 m(3)m(-2)h(-1) (empty bed residence time of 30s), the maximum elimination capacity for p-xylene was 40 g m(-3)h(-1) and removal efficiencies were in the range of 47-100%. The production of carbon dioxide (P(CO(2))) is proportional to elimination capacity (EC) and the linear relation was formulated as P(CO(2))=1.65EC+15.58. Stable pH values ranging from 6.3 to 7.6 and low pressure drop values less than 0.2 cm H(2)O (19.6 Pa) of packing media in compost-based biofilter of hybrid biofilter were observed, which avoided acidification and compaction of packing media and sustained the activity of microorganism populations.

Electrosorption isotherms and thermodynamics of phenol on activated carbon fibers (ACFs) in basic solution, as well as the factors (bias potential, initial concentration, and electrolyte) affecting adsorption/electrosorption kinetics, were investigated. The kinetics, which followed the Lagergren adsorption rate law, exhibited a variety of responses depending on bias potential, initial concentration, and electrolyte. The electrosorption isotherms were in agreement with the classical models of Langmuir and Freundlich, but the former gave more satisfactory correlation coefficients. With electrosorption at a bias potential of 700 mV from the basic solution, a nearly 10-fold enhancement of maximum adsorption capacity was achievable. The electrosorption free energy (DeltaG(ads)), enthalpy (DeltaH(ads)), and entropy (DeltaS(ads)) of phenol on the ACFs were calculated from adsorption isotherms at different temperatures. The results indicated that electrosorption of phenol in basic solution was spontaneous and exothermic. Furthermore, it was assessed that electrosorption occurred by dipole-dipole interaction with DeltaH(ads) of -20.14 kJ mol(-1) besides suppositional electrostatic interaction.

Enhancement of p,p'-DDT photodegradation on soil surfaces using TiO2 induced by UV-light was mainly investigated in this work. After being spiked with p,p'-DDT, soil samples loaded with different doses of TiO2 (0%, 0.5%, 1%, 2%, and 3% wt) were exposed to UV-light irradiation for 24 h. The results indicated that the photodegradation of p,p'-DDT followed the pseudo-first-order kinetics. TiO2 accelerated the photodegradation of p,p'-DDT significantly as indicated by the half-life reduction from 23.3 h to 10.4 h, corresponding to the TiO2 content from 0% to 3% respectively. In addition, the effects of soil pH, photon flux and humic substances on p,p'-DDT degradation were investigated. The photodegradation rate increased with the increase of the soil pH and photon flux. The humic substances (2% wt) inhibited the p,p'-DDT photodegradation by reducing the amount of light available to excite the p,p'-DDT and TiO2 or by quenching radicals capable of oxidizing p,p'-DDT. p,p'-DDE, p,p'-DDD and DDMU were main degradation intermediates and they were further degraded in the presence of TiO2.

An investigation was performed for the regeneration of three granular activated carbons (GACs) exhausted with acid orange 7 (AO7). The three GACs were made from different materials, i.e. coconut shells, almond nucleus and coal. The AO7 adsorption process was carried out in a continuous-flow adsorption column. After adsorption, the AO7-saturated GAC was dried at 120 degrees C, then regenerated in a quartz reactor by 2450 MHz microwave (MW) irradiation at 850 W for 5 min. The efficacy of this procedure was analyzed by determining the rates and amounts of AO7 adsorbed in successive adsorption-MW regeneration cycles. Effects of this regeneration on the structural properties, surface chemistry and the AO7 adsorption capacities of GAC samples were examined. It was found that after several adsorption-MW regeneration cycles, the adsorption rates and capacities of GACs could maintain relatively high levels, even higher than those of virgin GACs, as indicated by AO7 breakthrough curves and adsorption isotherms. The improvement of GAC adsorption properties resulted from the modification of pore size distribution and surface chemistry by MW irradiation.

Fourteen sediment samples with different content of Fe2O3 were collected from the lower reaches of the Liao River in China. The photodegradation of lindane on the surfaces of these sediments was investigated to observe the effects of Fe2O3 and other photoinducable substances, such as TiO2 and organic substances, on photodegradation of lindane. A partial least-squares (PLS) analysis model was developed to find out the statistical relationship between the photodegradation and the contents of these photoinducable substances. It was concluded from the PLS analysis that inorganic carbon and organic carbon have negative effects, whereas Fe2O3 and TiO2 accelerate the photodegradation of lindane in the sediment samples when 365 nm UV light was used as light source. In all cases of the experiments, the photodegradation of lindane in the sediment samples were fitted for pseudo-first-order kinetics.

Effects of organic matter and active Fe, Al, Mn oxides on the anaerobic degradation of gamma-666, p,p'-DDT were investigated by means of removing organic matter and hydrous metal oxides in Liaohe River sediments sequentially. The results showed that the anaerobic degradation of gamma-666, p,p'-DDT followed pseudo-first-order kinetics in different sediments; but, the extents and rates of degradation were different, even the other conditions remained same. Anaerobic degradation rates of gamma-666, p,p'-DDT were 0.020 d-1, 0.009 d-1 respectively for the sediments without additional carbon resources. However, with additional carbon resources, the anaerobic degradation rates of gamma-666, p,p'-DDT were 0.071 d-1 and 0.054 d-1 in the original sediments respectively. After removing organic matter, the rates were decreased to 0.047 d-1, 0.037 d-1. In the sediments removed organic matter and hydrous metal oxides, the rates were increased to 0.067 d-1, 0.059 d-1. This results indicated that organic matter in the sediments accelerated the anaerobic degradation of gamma-666, p,p'-DDT; the hydrous metal oxides inhibited the anaerobic degradation of gamma-666 and p,p'-DDT.