Color remediation of chemimechanical pulping effluent using combination of enzymatic treatment and Fenton reaction

This research investigated the efficiency of Advanced Oxidation Processes, Enzymatic treatment, and combined enzymatic/AOPs sequences on color remediation of CMP pulp and paper mills effluent. Regarding enzymatic treatment two kinds of fungal enzymes; Laccase (EC: 1.10.3.2) from Terametes Versicolor and Versatile Peroxidase (EC: 1.11.1.7) from Bjerkandera adusta were chosen and applied. Also, the effect of external mediator on the enzyme based degradations was studied. It was found that both VP from Bjerkandera adusta and Laccase from Terametes versicolor decolorized the deep brown effluent to a clear light yellow solution. It has been found that, concomitant use of enzymes and photo-Fenton process produces a considerable effect on color remediation. The data analysis of sequence treatment indicated that, chemical treatment after the enzymatic stage (photo-Fenton as a post treatment unit) yield a better performance for the CMP effluent.     

Performance of modified H-ZSM-5 zeolite for dehydration of methanol to dimethyl ether

The conversion of methanol to dimethyl ether was carried out over various commercial zeolites and modified H-ZSM-5 catalysts to evaluate their catalytic performance. A series of commercially available zeolite samples were used for vapor-phase dehydration of methanol to DME. Catalyst screening tests were performed in a fixed-bed reactor under the same operating conditions (T = 300 °С, P = 16 barg, WHSV = 3.8 h⁻¹). It was found that all the H-form zeolite catalysts in this study were active and selective for DME synthesis. According to the experimental results MDHC-1 catalyst exhibited the highest activity in dehydration of methanol.After finding the most active catalyst, the H-MFI90 zeolite was modified with Na content varying from 0 to 120 mol%, via wet-impregnation method to further improve its selectivity. All of catalysts were characterized by BET, XRD, NH₃-TPD, ICP, TGA, SEM, FT-IR and TPH techniques. It was found that these materials affected activity of MDHC-1 zeolite by changing its acidity. Ultimately, among all the catalysts studied, Na₁₀₀-modified H-MFI90 zeolite exhibited optimum activity, selectivity and stability at methanol dehydration reaction.     

A regularization-based deep unsupervised model for affine multimodal co-registration

Extensive network receptive field is key for unsupervised affine registration because instead of deformable registration that takes care of local subtleties, the affine registration is global so that the last layers need to see big patches of the organ-in-interest. To extend the network's receptive field, we need to go for deeper networks, which causes producing complex models. On the other hand, affine transformation is restricted by its low degree-of-freedom (DoF) where larger models increasingly develop the hazard of overfitting. To worsen the situation, the regularizer module cannot be applied to the affine transformation with such a restricted DoF. In this paper, we propose a differentiable computational layer to convert the affine transformation outputted by the network to its corresponding dense displacement field. Such an affine-to-field layer enables us to apply different regularization terms on the outputted transformation in order to avoid the overfitting phenomenon while deepening the network. The proposed approach was evaluated on an annotated hard multimodal dataset containing 1109 pairs of CT/MR images of the brain with different heterogeneity for example, variety in scanners, setups and resolutions. Based on the results, the proposed customized layer is fully successful to handle the overfitting for deeper networks that are able to produce richer transformations than the shallower networks from different evaluation metrics for example, in target registration error the proposed network with seven layers has a 13.3% (or 9.1 mm) improvement in performance. The implementation of the proposed customized affine-to-field layer in the Python, Keras package with the Tensorflow backend can be publically accessed via https://github.com/boveiri/Deep-coReg .     

Efficient XML data placement schemes over multiple mobile wireless broadcast channels

The Journal of Supercomputing - Broadcasting is one of the basic ways to access XML data via mobile wireless networks. In these networks, XML data are disseminated over a wireless broadcast channel...     

Evaluation of Water Balance in a Mountainous Upland Catchment Using SEBAL Approach

Scarcity of water is now the biggest threat in many parts of the world, specially in arid and semi arid regions. Establishing balance between water resources and the demands in a catchment scale basis could be one of the most important strategies to overcome this problem. In this regard, determination and analysis of water balance components (inputs and outputs) would be necessary. This study has focused on estimation of water balance components in arid-mountainous catchment of Manshad in Yazd province of Iran, during the year 2006–2007 using remote sensing and GIS techniques. To estimate actual evapotranspiration (ET_a) of the catchment, time series of MODIS images were obtained and used via Surface Energy Balance Algorithm for Land (SEBAL) approach. Measured precipitation (P) and runoff (R) data of the catchment were also used to calculate water balance equation components. Results indicated that a large volume of catchment water (about 70%) is wasted through evapotranspiration, while the rainfall is not enough to compensate this volume of water during the year. It seems that the negative (descending) trend has become dominant to the water budget of the area and gradually moves to harsh conditions of water shortage in future decades. Therefore, some actions would be necessary to overcome the problem. Water conservation strategies‚ improvement of water use efficiency, and control on agricultural field expansions are some solutions that could be advised for the studied catchment.     

Peroxopolyoxometalate nanoparticles blended PES membrane with improved hydrophilicity,anti-fouling,permeability, and dye separation properties

Poly(ethersulfone) (PES) is one of the polymers most widely used for the fabrication of ultrafiltration or nanofiltration membranes in various applications, but its membrane suffers from fouling. In this study, preparation, characterization, and performance of PES nanocomposite membrane comprising peroxopolyoxometalate nanoparticles was studied to provide improved permeability and anti-fouling properties. The high oxygen ratio of the PW₄ nanoparticles could enhance the hydrophilicity of the membranes. The PW₄ nanoparticles were characterized using Fourier transform infrared spectroscopy, scanning electron microscopy (SEM), energy dispersive X-ray (EDX), and X-ray diffraction analyses. The mixed matrix membranes were fabricated using a non-solvent induced phase-separation method. The fabricated membranes were characterized using atomic force microscopy, attenuated total reflection, SEM, EDX mapping, total average porosity, thermogravimetric analyze, and water contact angle experiments. The dye flux and rejection, pure water permeability and anti-fouling properties of the membranes were investigated. All of the membranes blended by different contents of the PW₄ nanoparticles presented better performance compared to the unmodified membrane. The filtration performance of the membranes in reactive green 19 (RG19) and reactive yellow 160 (RY160) dye separation showed that all of the PW₄ blended membranes possessed dye rejection greater than 86% and 96% for RY160 and RG19, respectively. The reusability test using bovine serum albumin (BSA) protein and RG19 dye solutions in five cycle experiments presented good reproductivity of the PW₄ blended membranes. The PES membrane containing 1 wt% of PW₄ nanoparticles showed the highest flux recovery ratio (75%) as well as reduced irreversible fouling ratio (8%) through BSA protein filtration.     

Biodegradable starch-based composites: effect of micro and nanoreinforcements on composite properties

Thermoplastic starch (TPS) matrix was reinforced with various kenaf bast cellulose nanofiber loadings (0–10 wt%). Thin films were prepared by casting and evaporating the mixture of aqueous suspension of nanofibers (NFs), starch, and glycerol which underwent gelatinization process at the same time. Moreover, raw fibers (RFs) reinforced TPS films were prepared with the same contents and conditions. The effects of filler type and loading on different characteristics of prepared materials were studied using transmission and scanning electron microscopies, X-ray diffractometry, Fourier transform infrared spectroscopy, thermogravimetric analysis, differential scanning calorimetry, and moisture absorption analysis. Obtained results showed a homogeneous dispersion of NFs within the TPS matrix and strong association between the filler and matrix. Moreover, addition of nanoreinforcements decreased the moisture sensitivity of the TPS film significantly. About 20 % decrease in moisture content at equilibrium was observed with addition of 10 wt% NFs while this value was only 5.7 % for the respective RFs reinforced film.     

Influence of polyethyleneimine layer and zinc nitrate on morphology and structure of PES-based membranes with highly selective properties

In this paper, nanofiltration (NF) polymer membranes based on polyestersulphone (PES) were prepared by the phase inversion method. Polyethyleneimine (PEI) and zinc nitrate (Zn(NO₃)₂) as a surface modifier and glutealdehyde (GA) as cross-linker was used. Fourier transform infrared spectroscopy analysis (FTIR) was used to confirm the chemical composition on the membrane surface. Membranes were also characterized using field emission scanning electron microscopy (FESEM) and 3D surface images. Water contact angle, average pore size and porosity measurements, water flux, salt rejection, and membrane anti-fouling ability were discussed. Modified membranes showed a smoother surface than the original membrane. The amount of pure water flux decreased with increasing the concentration of modifiers at the surface, but the yield of Na₂SO₄ salt increased, 53% in virgin membrane and 83% in M3 membrane. Modified membranes had better anti-fouling and hydrophilicity properties than primary membranes. The lowest contact angle value was 26.2° for M4. Also, the best anti-clogging comparable properties were for the M3 membrane with FRR = 63.37%, R_r = 10.69%, R_ir = 36.6%, and R_t = 47.3%. By increasing the concentration of modifiers, the removal of CuNO₃⁻ and CuSO₄ improved that the M1 membrane (97.59%) had the highest Cu(NO₃)₂ separation and the M4 membrane (87.5%) had the most increased CuSO₄ separation.