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Existing seismic design and assessment documents do not contain detailed specific guidance on seismic performance assessment of existing reinforced concrete (RC) structures, which have suffered from corrosion. This may cause unsafe consideration of reinforcement corrosion and, consequently, misleading seismic evaluation of such structures. In this study, six columns were subjected to different levels of accelerated corrosion process (causing different levels of damage, from slight to severe) and then were tested under constant axial and reversed cyclic lateral loading. The original aspect of the study is the clear demonstration of the adverse effect of corrosion on drift capacity of the columns. Furthermore, based on the test results, a method is proposed for calculating the deformation capacity of RC columns as a function of corrosion level for reliable seismic safety evaluation.

To remove ash and pyritic sulphur from bitumen an experimental study was performed to investigate the use of low frequency ultrasound wave in column flotation. For this purpose, a column flotation rig was equipped with a low frequency 24 kHz ultrasound transducer. The bitumen samples had sulphur content of 9.6 % (6.81 % in the pyritic sulphur form) and 26.4 % ash. All the experiments were carried out under pulp containing 5 % of solid, particle size of 100mesh and aeration rate of 4L/min using pine oil and kerosene as frother and collector agents, respectively. The effects of four parameters including the amounts of collector and frother agents, ultrasound power and ultrasound times were investigated. The optimum conditions for column flotation process with assisted ultrasound were; 1.5 kg/tbitumen of collector, 0.4 ppm of frother, ultrasound power equal to 300 W and ultrasound time of 3 min under flotation time of 5 min. In these conditions, 87.72 % of pyritic sulphur (i.e., 68.03 % of total sulphur) and 83.29 % of ash were removed. Accordingly, the enhancement of column flotation yield with ultrasound mode was approximately 11.9 and 10.3 % more than without ultrasound for ash and pyritic sulphur removal, respectively. The effect of process factors including amounts of collector and frother agents, ultrasound power and ultrasound time on ash and pyritic sulphur removal was investigated by central composite design (CCD) of RSM and multilayer feed forward back propagation neural network with the topology of 4-6-1.

One of the major determinants of Dupyutren disease (DD) treatment efficacy is recurrence of the contracture. Unfortunately, lack of agreement in the literature on what constitutes recurrence makes it nearly impossible to compare the multiple treatments alternatives available today. The aim of this study is to bring an unbiased pool of experts to agree upon what would be considered a recurrence of DD after treatment; and from that consensus establish a much-needed definition for DD recurrence. To reach an expert consensus on the definition of recurrence we used the Delphi method and invited 43 Dupuytren's research and treatment experts from 10 countries to participate by answering a series of questionnaire rounds. After each round the answers were analyzed and the experts received a feedback report with another questionnaire round to further hone in of the definition. We defined consensus when at least 70% of the experts agreed on a topic. Twenty-one experts agreed to participate in this study. After four consensus rounds, we agreed that DD recurrence should be defined as \"more than 20 degrees of contracture recurrence in any treated joint at one year post-treatment compared to six weeks post-treatment\". In addition, \"recurrence should be reported individually for every treated joint\" and afterwards measurements should be repeated and reported yearly. This study provides the most comprehensive to date definition of what should be considered recurrence of DD. These standardized criteria should allow us to better evaluate the many treatment alternatives.

This study investigates the efficacy of nano-zero-valent iron (nZVI) permeable reactive barriers (PRBs) as an in situ phosphate removal method. Batch equilibrium experiments were conducted to determine maximum adsorption capacity of nano-iron particles for phosphate to be 54.34 mg-P/g-Fe. Short-term experiment was performed for a period of a month through three sandy soil columns with different configurations of nZVI reactive layers. Initial concentration of 25 (PO 4 –P) mg/L was introduced to the columns, while effluent samples were collected for analysis. Numerical model was developed to simulate the 1-D advective–dispersive reactive transport of phosphate through the porous media in the three columns. Sensitivity analysis of model parameters was performed, expressed by the change in the effluent concentration with respect to variation in the value of model critical parameters. Optimization of transport process in columns was based on minimizing the sum of squared error values between measured and predicted effluent concentration. Phosphate breakthrough curves implied that Column 2 (C2) with two reactive layers showed a slight better performance in phosphate removal than Column 1 (C1) with maximum efficiency of 98.9% after only 17 h from the beginning of the experiment, whereas phosphate concentration in Column 3 (C3) reached the full saturation by the 9th day. The model verification with experimental data showed a reasonable agreement with a correlation coefficient ( R 2 ) ranging from 0.97 to 0.99. The results in this study confirmed that such presented model can be used for the promotion of the preliminary design of PRBs.

Distribution-based operational taxonomic unit-calling (dbOTU) improves on other approaches by incorporating information about the input sequences' distribution across samples. Previous implementations of dbOTU presented challenges for users. Here we introduce and evaluate a new implementation of dbOTU that is faster and more user-friendly. We show that this new implementation has theoretical and practical improvements over previous implementations of dbOTU, making the algorithm more accessible to microbial ecology and biomedical researchers.

A metal-organic framework, Zn-[2-methylimidazolate] frameworks (ZIF-8), was used as adsorbent material to remove different concentrations of oxytetracycline (OTC) antibiotic in a fixed-bed column. The OTC was studied at concentrations of 10, 25 and 40 mg L(-1). At 40 mg L(-1), the breakthrough point was reached after approximately 10 minutes, while at 10 and 25 mg L(-1) this point was reached in about 30 minutes. The highest removal rate of 60% for the 10 mg L(-1) concentration was reached after 200 minutes. The highest adsorption capacity (28.3 mg g(-1)) was attained for 25 mg L(-1) of OTC. After the adsorption process, a band shift was observed in the UV-Vis spectrum of the eluate. Additional studies were carried out to determine the cause of this band shift, involving a mass spectrometry (MS) analysis of the supernatant liquid during the process. This investigation revealed that the main route of adsorption consisted of the coordination of OTC with the metallic zinc centers of ZIF-8. The materials were characterized by thermal analysis (TA), scanning electron microscopy (SEM), powder X-ray diffraction (XRD), and infrared spectroscopy (IR) before and after adsorption, confirming the presence of OTC in the ZIF-8 and the latter's structural stability after the adsorption process.

This paper reports a complete micro gas chromatography (μGC) system in which all the components are lithographically microfabricated and electronically interfaced. The components include a bi-directional Knudsen pump, a preconcentrator, separation columns and a pair of capacitive gas detectors; together, these form the iGC3.c2 system. All the fluidic components of the system are fabricated by a common three-mask lithographic process. The Knudsen pump is a thermomolecular pump that provides air flow to the μGC without any moving parts. The film heaters embedded in the separation columns permit temperature programming. The capacitive detectors provide complementary response patterns, enhancing vapor recognition and resolving co-eluting peaks. With the components assembled on printed circuit boards, the system has a footprint of 8×10 cm 2 . Using room air as the carrier gas, the system is used to experimentally demonstrate the analysis of 19 chemicals with concentration levels on the order of parts per million (p.p.m.) and parts per billion (p.p.b.). The tested chemicals include alkanes, aromatic hydrocarbons, aldehydes, halogenated hydrocarbons and terpenes. This set of chemicals represents a variety of common indoor air pollutants, among which benzene, toluene and xylenes (BTX) are of particular interest. Gas sensors: An all-in-one solution A simple-to-produce, sensitive device for measuring hazardous pollutants in the home has been developed by researchers in the United States. Yutao Qin and Yogesh Gianchandani from the University of Michigan built the compact device, which works using a process known as gas chromatography. A pump forces a sample of air through a fluidic channel. The channel impedes various molecules in the sample to varying extent, enabling them to be identified. The researchers applied the technique of lithography — typically used in the electronics industry to make integrated circuits — to combine the gas pump, fluidic channels and electronic sensors required to read out the results of the analysis into a single package just a few centimeters in size. The device could detect benzene, toluene and other species with at concentrations lower than a hundred parts per billion.

Agricultural solid wastes either in natural or in modified forms have been successfully used for decades as non-conventional cost-effective adsorbents for removing metal ions and dyes from their aqueous phase and have been recognized as a sustainable solution for wastewater treatment. Therefore, this review article provides extensive literature information about heavy metals and dyes, their classifications and toxicity, various treatment methods with emphasis on adsorption characteristics by numerous agricultural solid wastes, or agricultural solid waste-derived adsorbents under various physicochemical process conditions. This review article not only provided an up-to-date information on the application of sustainable low-cost alternative adsorbents such as agricultural solid wastes, agricultural by-products, and biomass-based cost-effective activated carbon and various other natural materials in the batch adsorptive removal of heavy metal and dye from aqueous phase but also presented a comprehensive compilation of adsorptive pollutant removal information based on various reported continuous column operation studies which is one of the new aspect to this review article. The effectiveness of various batch and column operational process parameters on mechanistic adsorptive removal of both heavy metals and dyes by various agricultural solid waste-based adsorbents has been critically discussed here. Batch and column adsorption mechanism, batch kinetics, column dynamic modeling, and adsorptive behavior of adsorbents under various process parameters have also been critically analyzed and compared. Finally, literature information on recovery and regeneration through desorption techniques and cost comparison of various agricultural solid waste adsorbents with commercial activated carbons have also been reported here. Conclusions have been drawn from the literature reviewed, and few suggestions for future research direction are proposed.

During the horizontal jet grouting in soft ground, injection of large volumes of water and grout into the soil can lead to significant ground displacements. A simple method is proposed in this paper to predict the ground displacements caused by installing horizontal jet-grouting columns. The process of installing a horizontal column is simplified as the expansion of a cylindrical cavity with a uniform radial stress applied at plastic-elastic interface in a half plane. In this study, the analytical solution is adopted to calculate the deformation induced by the expansion of a cylindrical cavity. Considering the main jetting parameters (jetting pressure of the fluid, flow rate of the fluid, and withdrawal rate of the rod) and the soil properties (stiffness of the surrounding soil), an empirical equation to estimate the radius of plastic zone is developed. Two field tests are carried out in Shanghai, China, to verify the correctness and applicability of the proposed method. Comparisons between the predicted and measured values indicate that the proposed method can provide a reasonable prediction. The proposed simple method can be recommended as a useful tool for the design of ground improvement by means of horizontal jet grouting.

Short columns are designed as structural members having a high stiffness with low ductility and governed by brittle shear failures. During an earthquake, short columns are often the first members to fail. Therefore, their stiffness, strength, and collapse behavior are significant to the seismic evaluation of building structures. This study conducted tests of eight full-scale specimens to investigate the seismic behavior of short columns failed in shear. The test parameters include aspect ratio, hoop ratio, and axial load ratio. Test results show that, shear deformation accounted for a major part of the lateral deformation in short columns, and that the shear strength of short columns can be determined by strut-and-tie model. It was also found that, the degradation of shear strength beyond the peak value is a gradual process, and can be modeled by a straight line with a negative slope.