Predictive analysis of concrete slump using a stochastic search-consolidated neural network.

Attaining a dependable measurement of concrete slump is crucial as it is a valuable indication of concrete workability. On the other hand, complexities associated with costly traditional approaches have driven engineers to use indirect efficient models such as metaheuristic-based machine learning for approximating the slump. While the literature shows promising application of some metaheuristic techniques for this purpose, the large variety of these algorithms calls for evaluating the most capable ones to keep the solution updated. Stochastic fractal search (SFS) is one of the most powerful optimization algorithms in the literature that has not received appropriate attention in analyzing concrete mechanical parameters. In the present research, a multi-layer perceptron neural network (NN-MLP), is enhanced using the SFS. The proposed SFS-NN-MLP model aims to predict the slump based on the amount of ingredients in the mixture, as well as the curing age of specimens. Accuracy assessment revealed that the proposed model can deal with the assigned task with excellent accuracy. It indicates that the SFS could properly tune the parameters required for training the NN-MLP, and consequently, the trained network could reliably calculate the slump of specimens that were not analyzed before. For comparative validation, the SFS was replaced with two similar optimizers, namely elephant herding optimization algorithm (EHO) and slime mould algorithm (SMA). Based on the calculated mean square errors of 5.6526, 6.1129, and 7.3561 along with mean absolute errors of 4.6657, 5.0078, and 6.3066, as well as the percentage-Pearson correlation coefficients of 78.06 %, 73.95 %, and 58.11 %, respectively for the SFS-NN-MLP, EHO-NN-MLP, and SMA-NN-MLP, it was shown that the SFS-NN-MLP is the most accurate predictor. Hereupon, the SFS-NN-MLP model is recommended to be effectively used for obtaining a cost-efficient approximation of concrete slump in real-world projects.

Total phosphorus removal from domestic wastewater with Cyperus alternifolius in vertical-flow constructed wetlands at the microcosm level.

Vertical-flow constructed wetland (VFCW) is an effective alternative for removal of nutrients, heavy metals, and organic pollutants from wastewaters. This study investigated the uptake and removal of total phosphorus (TP) by Cyperus alternifolius from domestic wastewaters in the simulated VFCWs, The total of eight simulated VFCW treatments, including two different substrates, two different wet-to-dry ratios, and with and without C. alternifolius species (2 x 2 x 2 = 8), were utilized for an operation period of two years in this study. Results show that about 1.1 to 1.4 times more TP was removed from the influent with the presence of C. alternifolius as compared to without this plant species. A linear correlation existed between the aboveground biomass and its TP content. An increase in total biomass by 1000 g would result in an increase in TP accumulation in the aboveground biomass by 4.9 g. Large amounts of TP were removed by the substrate adsorption as compared to those by the aboveground biomass. Results suggest that, although substrate adsorption played a major role in TP removal, C. alternifolius uptake was an alternative pathway for further removal of TP from wastewaters in the VFCWs.

Identification of diaryl ether-based ligands for estrogen-related receptor α as potential antidiabetic agents.

Estrogen-related receptor α (ERRα) is an orphan nuclear receptor that has been functionally implicated in the regulation of energy homeostasis. Herein is described the development of diaryl ether based thiazolidenediones, which function as selective ligands against this receptor. Series optimization provided several potent analogues that inhibit the recruitment of a coactivator peptide fragment in in vitro biochemical assays (IC(50) < 150 nM) and cellular two-hybrid reporter assays against the ligand binding domain (IC(50) = 1-5 µM). A cocrystal structure of the ligand-binding domain of ERRα with lead compound 29 revealed the presence of a covalent interaction between the protein and ligand, which has been shown to be reversible. In diet-induced murine models of obesity and in an overt diabetic rat model, oral administration of 29 normalized insulin and circulating triglyceride levels, improved insulin sensitivity, and was body weight neutral. This provides the first demonstration of functional activities of an ERRα ligand in metabolic animal models.

Phosphorus sorption capacities and physicochemical properties of nine substrate materials for constructed wetland.

Constructed wetland (CW) is a promising technique for removal of pollutants from wastewater and agricultural runoff. The performance of a CW to remove pollutants, however, hinges on the use of suitable substrate materials. This study examined the physicochemical properties and phosphorus (P) sorption capacities of nine different CW substrate materials using both batch experiments and the Freundlich as well as the Langmuir isotherm. The nine substrate materials used in this study were turf, topsoil, gravel, midsized sand (MSS), blast furnace slag (BFS), coal burn slag (CBS), blast furnace artificial slag (BFAS), coal burn artificial slag (CBAS), and midsized artificial sand (MSAS). Experimental data showed that sorption of P increased with initial solution P concentrations for all nine substrate materials. The maximum P sorption capacity of the substrate materials estimated by Langmuir isotherm was in the following order: turf (4243 mg/kg substrate) > BFAS (2116 mg/kg substrate) > BFS (1598 mg/kg substrate) > CBS (1449 mg/kg substrate) > top soil (1396 mg/kg substrate) > CBAS (1194 mg/kg substrate) > MSAS (519 mg/kg substrate) > gravel (494 mg/kg substrate) > MSS (403 mg/kg substrate). The specific gravity of eight substrate materials (except gravel) had very significant negative correlations with the P sorption, whereas the particle diameter of D(60) and uniformity coefficient (K(60)) had positive correlations with the P sorption. The cation exchange capacity, organic matter, available ferrous, and exchangeable aluminum of the eight substrate materials also had very significant positive correlations with the P sorption, while the pH of the substrate materials showed a very significant negative correlation with the P sorption. Our study further suggests that turf and CBAS are the two relatively ideal substrate materials suitable for removal of P from a CW system.

Performance of hybrid constructed wetland systems for treating septic tank effluent.

The integrated wetland systems were constructed by combining horizontal-flow and vertical-flow bed, and their purification efficiencies for septic tank effluent were detected when the hydraulic retention time (HRT) was 1 d, 3 d, 5 d under different seasons. The results showed that the removal efficiencies of the organics, phosphorus were steady in the hybrid systems, but the removal efficiency of total nitrogen was not steady due to high total nitrogen concentration in the septic tank effluent. The average removal rates of COD (chemical oxygen demand) were 89%, 87%, 83%, and 86% in summer, autumn, winter and spring, respectively, and it was up to 88%, 85%, 73%, and 74% for BOD5 (5 d biochemical oxygen demand) removal rate in four seasons. The average removal rates of TP (total phosphorous) could reach up to 97%, 98%, 95%, 98% in four seasons, but the removal rate of TN (total nitrogen) was very low. The results of this study also indicated that the capability of purification was the worst in winter. Cultivating with plants could improve the treated effluent quality from the hybrid systems. The results of the operation of the horizontal-flow and vertical-flow cells (hybrid systems) showed that the removal efficiencies of the organics, TP and TN in horizontal-flow and vertical-flow cells were improved significantly with the extension of HRT under the same season. The removal rate of 3 d HRT was obviously higher than that of 1 d HRT, and the removal rate of 5 d HRT was better than that of 3 d HRT, but the removal efficiency was not very obvious with the increment of HRT. Therefore, 3 d HRT might be recommended in the actual operation of the hybrid systems for economic and technical reasons.

[Purification efficiency of vertical-flow wetland system constructed by cinder and turf substrate on municipal wastewater].

Vertical-flow constructed wetlands (VFCWs) system not only has a higher hydraulic loading rate (54-64 cm.d-1), but also has a good removal efficiency for organics, ammonia nitrogen (AN) and total phosphorus (TP). The removal efficiencies of COD, BOD5, AN, and TP for septic tank effluent were 76-87%, 82-92%, 75-85% and 77-91%, respectively, and the average effluent concentrations of COD, BOD5, AN, and TP in the treated effluent were less than 60, 20, 25 and 2.0 mg.L-1, respectively. A comparison of planted and unplanted columns showed that plantation of Cyperus alternifolius could increase the removal rates of AN, TN, and TP by 2-3%, 4-6%, and 10-14%, respectively.

[Advances in the research of infiltration wetland wastewater treatment systems].

As their high purification efficiency and relatively low capital investment and treatment cost, infiltration wetland wastewater treatment systems have been popular, and are being increasingly applied in many countries. In this paper, the bed structure and filtering media, nitrogen and phosphorus removal processes and purification mechanisms, performance, current design criteria, operation and regulation mechanisms, soil clogging problem and solutions, and combination of vertical-horizontal flow wetlands treatment system and its use in different types of wastewater treatment were introduced and summarized. Finally, the future research directions of this technique were also discussed.

Treatment and utilization of septic tank effluent using vertical-flow constructed wetlands and vegetable hydroponics.

Vertical flow constructed wetlands is a typical ecological sanitation system for sewage treatment. The removal rates for COD, BOD5, SS, TN, and TP were 60%, 80%, 74%, 49% and 79%, respectively, when septic tank effluent was treated by vertical flow filter. So the concentration of COD and BOD5 in the treated effluent could meet the quality standard for irrigation water. After that the treated effluent was used for hydroponic cultivation of water spinach and romaine lettuce, the removal efficiencies of the whole system for COD, BOD5, SS, TN and TP were 71.4%, 97.5%, 96.9%, 86.3%, and 87.4%, respectively. And it could meet the integrated wastewater discharge standard for secondary biological treatment plant. It was found that using treated effluent for hydroponic cultivation of vegetables could reduce the nitrate content in vegetables. The removal rates for total bacteria and coliform index by using vertical flow bed system with cinder substrate were 80%-90% and 85%-96%, respectively.

[PAEs in composts of municipal sludge and rice straw].

Four composting treatments for municipal sludge and rice straw were carried out, which included turning composting, inoculation-turning composting, continuous aeration, and intermittent aeration. GC/MS determination of phthalic acid esters (PAEs) in different composted composts showed that the total contents of six PAE compounds (sigma PAEs) ranged from 0.980-17.832 mg.kg-1, decreasing in the order of turning composting (17.832 mg.kg-1) > inoculation-turning composting (13.927 mg.kg-1) > intermittent aeration (10.765 mg.kg-1) > continuous aeration (9.815 mg.kg-1). DnOP was dominated in the composts. The degradation rate of sigma PAEs after composting was 1.37-45.71% (mean 27.63%), and that of diethyl phthalate (DEP), di-n-butyl phthalate (DnBP) and butylbenzyl phthalate (BBP) was 95.76-98.68%, 79.56-99.46% and 87.42-98.42%, respectively. The concentration of di-n-octyl phthalate (DnOP) was increased in the composts. Aeration-composting, and continuous aeration composting in particular, was more efficient than other treatments to degrade PAEs in municipal sludge.

[Effect of municipal sludge and chemical fertilizers on phthalic acid esters (PAEs) contents in Ipomoea aquatica grown on paddy soils].

GC/MS determinations on six phthalic acid esters (PAEs) in Ipomoea aquatic grown on potted paddy soil fertilized with municipal sludge and chemical fertilizers showed that the total contents of PAEs (sigma PAEs) in Ipomoea aquatic aboveground parts ranged from 2.129 mg.kg-1 to 7.111 mg.kg-1, decreasing in order of Guangzhou sludge + fertilizers (7.111 mg.kg-1) > Guangzhou sludge (4.767 mg.kg-1) > Foshan sludge (3.569 mg.kg-1) > Foshan sludge + fertilizers (3.305 mg.kg-1) > fertilizers (2.638 mg.kg-1) > control (2.129 mg.kg-1), indicating that compared with control, fertilization increased sigma PAEs in Ipomoea aquatica to a different extent. Only certain compounds of PAEs in different treatments of Ipomoea aquatica were dominant, e.g., butylbenzyl phthalate (BBP) in control, chemical fertilizers, Foshan sludge, and Guangzhou sludge accounted for 40% to 80% of sigma PAEs, di-n-butyl phthalate(DnBP) in foshan sludge + chemical fertilizers accounted for 56%, while di-n-octyl phthalate(DnOP), di(2-ethylhexyl)phthalate(DEHP) and BBP in Guangzhou sludge + chemical fertilizers accounted for approximately 30%. sigma PAEs and the contents of its most compounds were higher in the plants of Ipomoea aquatica than in its roots to a different extent.

[Effect of sewage sludge and its composts on the accumulation of organic pollutants in Ipomoea aquatic grown in paddy soil].

Eight kinds of organic pollutants including 44 compounds in Ipomoea aquatic grown in paddy soil fertilized with sewage sludge and its composts were systematically determined by GC/MS. The results showed that twenty eight compounds consisting mainly of phthalic acid esters, nitrobenzenes, and polycyclic aromatic hydrocarbons were deteced in Ipomoea aquatic. Only individual or very few compounds for each kind of organic pollutants in Ipomoea aquatic were predominant, while others were trace or not detected. Compared with control, compounds detected in Ipomoea aquatic fertilized with sludge were commonly higher to a different extent, but those detected in Ipomoea aquatic fertilized with different sludge composts were commonly lower and even not detected, especially for Ipomoea aquatic fertilized with sludge + rice straw composts was detected only one compound. It was therefore concluded that direct use of sewage sludge as organic fertilizer could result in bioaccumulation of organic pollutants in crops, but sludge compost application would be safe if proper compost treatment for sludge was conducted.