Suitable Treatment Conditions Research Articles

Effects of High-Speed Shearing Treatment on the Physical Properties of Carbohydrate-Binder Mixture during Gelatinization for Preparing Freeze-Dried Soup Products.

Modernization has led to a large convenience food market, and the demand for freeze-dried (FD) soup products is increasing in the Republic of Korea. FD soup products are easy to eat without cooking and can be stored for long periods. However, it is often difficult to ensure sensory satisfaction after rehydration of FD soup products; in particular, the ingredients are not evenly dispersed. Therefore, a stable dispersion or reconstitution of the FD soup products is required after rehydration. Here, the effects of high-speed shearing homogenization on the physical properties of a carbohydrate-binder mixture comprising maltodextrin, potato starch, and rice flour were investigated during hydrothermal gelatinization. To find a suitable treatment condition, different homogenization eras, speeds, and concentrations of the binder mixture were considered; in particular, the homogenization eras were set by considering the hydrothermal property of the binder mixture profiled using differential scanning calorimetry. The viscosity of the binder mixture and the compression strength and microstructure of the FD binder block, including the dispersion stability after rehydration, were evaluated. The quality of the FD binder block was improved by homogenization above 5000 rpm when the core temperature of the binder mixture reached approximately To at 14.5-21.8% concentrations. The improved FD binder block exhibited a fine surface and tiny porous microstructure compared with the control (with continuous agitation at 250 rpm). The control block was divided into two phases, whereas the improved block maintained the initial dispersion stability at 50 °C for 1 h. These results are expected to be referenced for the purpose of improving the quality of the FD soup products.

Novel polyferric titanium silicate/chitosan composite flocculant for organic polymeric pollutant removal: optimization, performance and mechanism

A novel inorganic-organic composite flocculant polyferric titanium silicate/chitosan (PFTS/CTS) was successfully synthesized in this study. The optimal preparation parameters of flocculant were optimized by orthogonal experiment with organic polymer polyacrylamide (PAM) removal rate as the evaluation index. The results shows that the examined preparation parameters are in the order of aging time > m(Fe + Ti):m(CTS) > n(Fe + Ti):n(Si), and the best experimental formula is that aging time = 2 days, m(Fe + Ti):m(CTS)=5 and n(Fe + Ti):n(Si)=0.5. The obtained PAM (50 mg/L) removal rate is 78.7% under the selected suitable wastewater treatment condition. Compared with the single CTS, PFTS and polyferric silicate (PFS), PFTS/CTS exhibits superior flocculation performance. The reason for the improvement of flocculation performance of PFTS/CTS can be attributed to its good crystallinity, special scaly accumulation structure and high positive charge, as well as the synergistic effect of inorganic flocculant and organic flocculant in the PFTS/CTS flocculant, which is successfully composited through coordination bond between titanium ions of PFTS and hydroxyl or amino groups of CTS. The main mechanism of treating PAM by PFTS/CTS is physical and chemical effect including micro-flocs are formed through chelate, charge neutralization and adsorption in the first process, and then the larger particles are formed by bridging, wrapping and sweeping. In addition, the flocs of treating PAM using PFTS/CTS are dense and large, its formation and the sedimentation are fast. The prepared flocculant exhibits eminent application prospects in the field of PAM wastewater.

Production of Biocalcium from Fermented Fish Bone Residue for Fish Emulsion Sausage Fortification.

Fermented fish bone residue (FFBR) is an underused by-product of the industrial-scale production of fermented fish sauce. Subjecting FFBR to proper alkaline treatment can transform FFBR into biocalcium, which can be added to fish emulsion sausage (FES) to increase its calcium content. This study comprised two experiments. First, we aimed to find the most suitable alkaline treatment conditions for preparing biocalcium from FFBR. Alkaline treatments combining three sodium hydroxide (NaOH) concentrations (0%, 3%, and 6%) and three soaking times (0, 1, and 2 h) were tested. Quality parameters of alkaline-treated biocalcium (crude protein, crude fat, ash content, calcium, phosphorus, crude fiber, salt content, CIE color values, morphology of biocalcium particles, and the intensity of the fermented fish smell) were assessed. Second, we fortified FES with the properly treated biocalcium (0, 12, 24, or 36 g) and evaluated the sausage's calcium, phosphorus, crude fiber, salt content, pH, CIE color values, texture profile analysis (TPA), emulsion stability, and sensory criteria. It was found that treatment with 3% or 6% NaOH produced better crude protein, ash content, calcium, and CIE color value results than no alkaline treatment. These two NaOH concentrations effectively lowered the salt content and the intensity of the fermented fish smell. However, 3% and 6% NaOH produced similar results. A soaking time of 1 h or 2 h produced better results than no soaking in terms of crude protein, crude fat, ash content, calcium, phosphorus, CIE color values, and the intensity of fermented fish smell. However, 1 h and 2 h produced similar results. It is concluded that 3% NaOH and soaking for 1 h would be the most suitable alkaline treatment to prepare biocalcium from FFBR. Fortifying FES with biocalcium from FFBR increased the calcium and phosphorus contents but slightly reduced TPA. The other FES quality parameters were unaffected by biocalcium fortification.

Dimensional Stability and Mechanical Properties of Gmelina arborea Roxb. Wood Thermally Modified through Open Reactor and Low-Pressure Closed Reactor Systems

This study focused on the thermal modification of Gmelina arborea Roxb. wood following processes using the open reactor and low-pressure closed reactor systems. The aim is to determine the optimum treatment conditions suitable for gmelina wood due to its poor drying characteristics using the low-pressure closed reactor thermal modification. Subsequent to thermal modification under both processes, the dimensional stability and mechanical properties of gmelina wood were investigated. Effects of the thermal modifications under the open and low-pressure closed reactor systems on mechanical properties were additionally reported. The outcome of this investigation revealed that mass loss increased with increasing treatment temperatures, but minimal mass losses were observed for samples modified in the low-pressure closed reactor system. Due to the low-pressure regime used in the closed reactor system, a lesser improvement was found in volumetric shrinkage, fibre saturation point and tangential-to-radial swelling compared to the improvement in these properties in the open reactor system. Results further revealed that the mechanical properties of gmelina wood deteriorated more rapidly after modification in the open reactor system. Since the properties of modified gmelina wood are comparable at 180 °C under both systems, the closed reactor system will be investigated further to arrive at a suitable treatment condition under higher pressure variations. The thermal modification of gmelina wood with the closed reactor system is more promising in delivering a better quality of modified gmelina wood.

Study on mutual harmless treatment of electrolytic manganese residue and red mud.

Electrolytic manganese residue (EMR) and red mud (RM) are solid waste by-products of the metal manganese and alumina industries, respectively. Under long-term open storage, ammonia nitrogen and soluble manganese ions in EMR and alkaline substances in RM severely pollute and harm the environment. In order to alleviate the pollution problem of EMR and RM. In this study, the alkaline substances in RM were used to treat ammonia nitrogen and soluble manganese ions in EMR. The results confirm the following suitable treatment conditions for the mutual treatment of EMR and RM: EMR-RM mass ratio = 1:1, liquid-solid ratio = 1.4:1, and stirring time = 320min. Under these conditions, the elimination ratios of ammonia nitrogen (emitted in the form of ammonia gas) and soluble manganese ions (solidified in the form of Mn3.88O7(OH) and KMn8O16) are 85.87 and 86.63%, respectively. Moreover, the alkaline substances in RM are converted into neutral salts (Na2SO4 and Mg3O(CO3)2), achieving de-alkalinisation. The treatment method can also solidify the heavy metal ions-Cr3+, Cu2+, Ni2+, and Zn2+-present in the waste residue with leaching concentrations of 1.45mg/L, 0.099mg/L, 0.294mg/L, and 0.449mg/L, respectively. This satisfies the requirements of the Chinese standard GB5085.3-2007. In the mutual treatment of EMR and RM, the kinetics of ammonia nitrogen removal and manganese-ion solidification reactions are controlled via a combination of membrane diffusion and chemical reaction mechanisms.

Controlled growth and spectroscopy characterization of blue violet perovskite quantum dots in borate glasses

Blue violet light emitting CsPb(Cl/Br)3 perovskite quantum dots glasses (QDGs) have been successfully fabricated in multi-component borate glass matrix by melt quenching and heat treatment. The spectral characteristics have been evaluated by photoluminescence (PL), PL excitation (PLE), PL decay and absorption spectra. The recipe and preparation conditions have been optimized for controlled growth of QDs. By using raw materials of NH4Br/NH4Cl/PbO and crucible cover, optimizing composition of Na2O/K2O in matrix, melting temperature and time, heat treatment temperature and time, and NH4Cl and NH4Br contents, we have finally realized blue violet exciton emission in target range of 405–440 nm. The PL wavelength adjustment is comprehensive effect of the abovementioned influence factors. The emission in short wavelength of 405–440 nm is due to controlled growth of the QDs. In final CsPb(Cl/Br)3 QDs, the contents of Cl and Br are suitable and the Cl/Br ratios are large. A little Br is necessary for growth of CsPb(Cl/Br)3 QDs and then the Br is partially replaced by Cl at suitable treatment condition. Unsymmetrical PL spectrum profile of some samples is explained as reabsorption effect by monitoring PL spectral profile and PL decay. The temperature characteristics of PL spectra show good recoverability after a temperature cycle.

Changes in the physiochemical, flavor and stability of whey protein solutions during UHT processing and storage: a review

A growing product on the worldwide dairy market is ultra-high temperature (UHT) milk, which can be kept at room temperature for 6 to 9 months. As the milk undergoes either direct or indirect UHT treatment at 140 ℃ for a few seconds, could kill the majority of bacteria and heat-resistance enzymes. The whey protein in milk will experience a series of physiochemical reactions such as denaturation, proteolysis, age gelation, sedimentation and Maillard after UHT treatment and following storage. The aims of this review were to screen occurred reactions in whey protein, allocate the generated flavor and analysis the volatile compounds. This review explained the mechanisms of the physiochemical reactions, and analysed the related flavor and relevant compounds of the flavor. Also, proposing several suggestions to improve UHT milk quality and find out suitable treatment conditions to prevent or minimize the effects of UHT on whey proteins.

Reusing sludge from surface water treatment plant for hexavalent chromium adsorption in aqueous solution

Contaminants in plating wastewater are hard to remove, especially hexavalent chromium ions. This waste stream contains a large amount of Cr6+, a highly toxic metal, potential to cause cancer. To reduce this pollution, sludge from a supply water treatment plant (DWTS) has been used to make adsorbent. This sludge was denaturized by thermal method. After that, a plating synthetic waste stream contained Cr6+ was treated by a batch adsorption model with adsorbent made from DWTS. pH, amount of adsorbent, and treatment time were investigated to determine the suitable treatment conditions. The study was also evaluated the suitability of two adsorption models Langmuir and Freundlich. Results showed that, under the conditions of pH = 6.0, the adsorbent content of 25.0 g/l, after 90.0 minutes, Cr6+ content remained 0.14 mg/l, close to QCVN 40:2011/BTNMT, column B. The parameters of the Langmuir and Freundlich adsorption equations are: qmax = 12.578 mg/g; Kads = 0.747 l/mg; n = 0.338; kf = 5.138. The Freundlich isothermal model is better fitted to the chromium adsorption process than Langmuir isothermal model.

Cold plasma treatment to prepare active polylactic acid/ethyl cellulose film using wheat germ peptides and chitosan

In this study, the surface of the polylactic acid/ethyl cellulose (PLA/EC) blend film was modified by dielectric barrier discharge (DBD) plasma treatment to facilitate the spin-coating of chitosan (CH) and wheat germ bioactive peptides (PEP) obtained from enzymatic hydrolysis of defatted wheat germ protein isolate on the surface of the film. The suitable plasma treatment condition was 5 min at 20 kV according to ATR-FTIR, AFM, SEM, water angle contact, and water solubility results. Increasing the surface roughness and oxygen-containing functional groups (CO and −OH) improved coating by PEP and CH. The PEP-coated film had better antioxidant activity than CH-PEP and CH-coated films. The results of antimicrobial activity demonstrated that PEP-coated film could reduce the growth of gram-negative bacteria (Escherichia coli) and gram-positive bacteria (Staphylococcus aureus). The PEP-coated film had competitive antibacterial properties with CH-coated. Hence, the obtained PEP-coated PLA/EC film could be a promising candidate for antioxidant and antibacterial food packaging.

A novel strategy for treating chromium complex wastewater: The combination of a Fenton-like reaction and adsorption using cobalt/iron-layered double hydroxide as catalyst and adsorbent

Advanced oxidation processes (AOPs) are promising technologies to treat wastewater containing heavy metal complexes, and the main challenge of treating wastewater containing chromium (Cr) complexes by these processes is the formation of more toxic and soluble hexavalent Cr (Cr(VI)). In this study, we proposed a combination process of a Fenton-like reaction and adsorption (Fenton-like reaction/adsorption) using cobalt/iron-layered double hydroxide (Co/Fe-LDH) as catalyst and adsorbent to treat Cr complex-containing wastewater. The results showed that the Cr(VI) formed during treatment process could be adsorbed by the Co/Fe-LDH immediately after its formation. The Co/Fe-LDH dosage was the key factor affecting the total Cr removal, and the initial pH of the solution was the key factor affecting the Co leakage from the material. Under suitable treatment conditions, the total Cr concentration could be reduced to less than 1.5 mg L−1. The superoxide free radical (O2−) is the main radical species in this process. During treatment, part of Cr(III) in Cr(III)-citrate is oxidised into Cr(VI), and the corresponding organic ligand is decomposed to H2O, CO2 or some intermediate products. Then, the released Cr(VI) and undecomposed Cr(III)-citrate are removed via the adsorption of Co/Fe-LDH. This study established a feasible strategy to treat wastewater containing Cr complexes by AOPs and avoid Cr(VI) accumulation.

Solvothermal synthesis of oxygen deficient tungsten oxide nano-particle for dual band electrochromic devices

Dual-band electrochromic smart windows can dynamically and independently control near infrared (NIR) and visible (Vis) light, and are considered a promising technology for improving building energy efficiency. However, most existing dual band electrochromic materials consist of complex nanocomposites, and it is difficult to balance the delicate composition of each constituent. Recently, to solve these problems, research has been conducted on single component dual-band electrochromic materials, in particular, oxygen deficient tungsten oxide (WO3-x) nanostructures. In this study, WO3-x nanoparticles were synthesized using a simple solvothermal method, and highly dispersible inks were formulated which could be deposited at relatively low temperature via various solution-based coating methods. Various analysis techniques including XRD, HR-TEM and in-situ spectroelectrochemical measurements revealed that the oxygen-deficient WO3-x composition remained intact up to an annealing temperature of 350 °C. Under suitable thermal treatment conditions, the resulting WO3-x films could independently and dynamically control NIR and VIS light transmittance. When a moderate voltage of −0.4 V was applied, the NIR light was mainly blocked via a capacitive charge mechanism, with optical modulations of 23.81% and 72.48% at 550 nm and 1200 nm, respectively. A further increase in applied voltage to −1.2 V led to the blocking of both VIS and NIR light through faradaic Li+ ion insertion with optical modulations of 71.13% and 84.57% at 550 nm and 1200 nm, respectively. Moreover, the optical modulations were maintained for 1000 consecutive cycles. This work demonstrates a single component dual-band electrochromic material that can be useful for various applications such as electrochromic smart windows.

Efficient MnOx-CeO2/Ti-bearing blast furnace slag catalyst for NH3-SCR of NO at low temperature: Study of support treating and Mn/Ce ratio

Exploring novel low-temperature SCR catalyst supports with excellent properties and low cost is a significant challenge. Ti-bearing blast furnace slag (Ti-BFS) presented great potential in this field due to high contents of Ti, Si and Al elements. In this work, Ti-BFS was pretreated and optimized by hydrochloric solution, and suitable treatment conditions were obtained. Ti and Si were well enriched and other components (especially Ca) were mostly leached, while the modified slag exhibited well-developed porosity and high surface area. An efficient MnOx-CeO2/Ti-bearing blast furnace slag catalyst (Mn-Ce/ATS) can be developed by loading appropriate MnOx-CeO2 ingredients on this support. 4Mn-Ce/ATS catalyst performed better SCR performance because of its excellent NH3 adsorption capacity and reactivity, as well as more alkali sites. Cerium was beneficial to bond NH3 species and manganese was advantageous to adsorb NO. Although SO2 resistance of this catalyst was relatively undesired, its H2O resistance was perfect. This work can provide a guidance on realizing waste Ti-bearing blast furnace slag utilization and reducing the denitrification cost.

Abstract LB051: The landscape of peptide vaccinein clinical trials for cancer

Abstract Background: For an anticancer immune response to lead to the effective killing of cancer cells, a key determinant is selecting suitable immunogenic tumor antigens as the immunotherapy targets. Recent studies have highlighted the relevance of tumor-associated antigens encoded by amino acid substitutions (AASs) in recognition of cancer cells by the immune system. This has prompted the development of personalized vaccines and cell therapies targeting cancer mutations. Recently immunotherapy has been merged as a promising new treatment method for cancer due to its remarkable anti-tumor efficacy and low side effects. One of the key factors limiting the application of immunotherapy is the lack of suitable tumor antigens. Our work aims to investigate what kinds of tumor antigens and treatment conditions can help obtain satisfactory clinical treatment results.Finding: We collected tumor-associated antigens of clinical tumor peptide vaccine therapy from different databases and constructed a tumor antigens library. Candidate tumor peptides can activate T cells to release IFN-ϒ and have high cytotoxicity for tumor cells. They could be used as peptide vaccines or as targets for adoptive cell therapy (DC cells, CTL cells, TCR-T cells, CART cells). To find the causes which influence peptide vaccine treatment effect. Several significant factors, including peptide antigens, peptide types, adjuvants, and treatment strategy, were analyzed in response results and no response results. We found that most peptides, which were used in clinical cases, are an expression or high expression. There are more overexpression peptides than other types of peptides ineffective results of colorectal (P=0.0002). But fusion peptide vaccines have no advantages in cancer peptide vaccine therapy. Modify or high expression peptides could be suitable alternative peptides for peptide vaccine in cancer immunotherapy, especially melanoma immunotherapy. Although the SNV peptides have no significant therapeutic advantages in non-individualized vaccine therapy, tumor neo-antigen peptides maybe have significant benefits in individualized vaccine therapy. GM-CSF and ISA-51 are the two most common adjuvants, and IL-4, IL-4, IL-12 are the main cytokines and additives in response results, especially in breast cancer and melanoma. But most cases did not use any adjuvants in peptide vaccine preparation.We also found that PMEL, MAGE-1,4,3,6, SART3, LCK, TP53, CEA, and ERBB2 are the top 8 antigens of clinical phase peptides. The antigens of response peptides are also significant differences in different cancers. Treatment strategy also plays a vital role in the therapeutic efficacy of peptide vaccine. The interval of 1-2 weeks and more than 4 times vaccine could be the typical treatment strategy for response clinical trials.Conclusions: Peptide vaccines provide apparent advantages in comparison to traditional therapies. Peptide vaccine production is relatively inexpensive due to the ease of production and simplistic composition. Moreover, peptide vaccines can be composed of various epitopes from different antigens and integrate T cell and B cell epitopes into one antigenic formulation. It is crucial to choose suitable peptide antigens and treatment conditions for cancer vaccine therapy.Keywords: Peptide vaccine; Clinical trials; Cancer; Phase- 1 - Citation Format: Chongming Jiang, Geng Liu, Wei Zhang, Zhenkun Zhuang, Wenhui Li, Si Qiu, Cheng-chi Chao, Bo Li, Chao Cheng. The landscape of peptide vaccinein clinical trials for cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr LB051.

Effect of Plasma Treatment on the Impact Behavior of Epoxy/Basalt Fiber-Reinforced Composites: A Preliminary Study

Hydrophobic surfaces are highly desired for several applications due to their exceptional properties such as self-cleaning, anti-icing, anti-friction and others. Such surfaces can be prepared via numerous methods including plasma technology, a dry technique with low environmental impact. In this paper, the effect of a one-step sulfur hexafluoride (SF6) plasma treatment upon the low velocity impact behavior of basalt/epoxy composites has been investigated by using several characterization techniques. A capacitive coupled radiofrequency plasma system was used for the plasma surface treatment of basalt/epoxy composites, and suitable surface treatment conditions were experimentally investigated with respect to gas flow rate, chamber pressure, power intensity, and surface treatment time by measuring the water droplet contact angle of treated specimens. The contact angle measurements showed that treating with SF6 plasma would increase the hydrophobicity of basalt/epoxy composites; moreover, the impact results obtained on reinforced epoxy basalt fiber showed damage in a confined area and higher impact resistance for plasma-treated basalt systems.

Effect of Normalizing Treatment on Mechanical Properties of AISI 441 Stainless Steel Prepared by Investment Casting

In this paper, AISI 441 stainless steel was investigated as a casting steel using the investment casting process (ICP). The microstructure and mechanical properties of the as-cast and normalizing treatment samples were analyzed. The results show that the tensile strength of as-cast AISI 441 prepared by ICP is 458 MPa, and the elongation is 22.7%. Normalizing treatment can improve the mechanical performance of AISI 441 prepared by ICP, but strength and elongation have a slightly decreasing trend with increasing normalizing temperature and time. The suitable normalizing treatment condition is 850 °C for 2 h. It was found that normalizing temperature and time have little effect on grain size and carbonitride. There was an increasing trend in the mean equivalent length (MEL) of the Laves phase as normalizing temperature and time increases. The effect of normalizing treatment on strength increment was mainly related to the change of the Laves phase size.

Isolation, identification and thermal inactivation of dominant spoilage bacteria in egg curds

The egg curd is one of the most promising ready-to-eat egg products in China, which can greatly enhance the commercial value of eggs. At present, there are few studies on the spoilage bacteria of egg curds and the suitable heat treatment condition remains obscure. This study isolated and identified the spoilage bacteria from egg curds and then determined a suitable heat treatment condition. Bacillus velezensis EC 1 and Bacillus cereus EC 2 were isolated from spoiled products. The B. velezensis EC 1 spore was more thermal resistant than B. velezensis EC 1. The D90, D95 and D100 values of B. cereus EC 2 spores were 7.97, 2.23 and 0.93 min respectively, while the values of B. velezensis EC 1 spores were 26.87, 6.80 and 2.18 min, respectively. Based on the above D-values, we designed several heat treatment intensities and evaluated the heat treatment effect through shelf-life experiment. The egg curds heated at 100 °C for 10 min could maintain microbial safety during the 180-day storage period and the pH, total volatile basic nitrogen and thiobarbituric acid reactive substances values were relatively more stable. Therefore, in this study, the most suitable heat treatment condition for egg curds is 100 °C, 10 min. These findings will provide realistic guidance for egg curd manufacturers.

Antimicrobial photodynamic efficacy of selected natural photosensitizers against food pathogens: Impacts and interrelationship of process parameters.

Photodynamic treatment (PDT) could be a viable option to decontaminate food or food contact surfaces. Such applications require a rigorous method to assess the efficacy of different photosensitizer-light source systems. It is also essential to determine suitable treatment conditions to achieve desirable microbial inhibition for a given process. In this connection, we evaluated and compared the antimicrobial activity of two natural photosensitizers (aloe emodin, curcumin) under PDT based on the number of absorbed photons. The degree of bacterial inactivation was then correlated to the absorbed photons as well as the process parameters through kinetics study. The results showed that aloe emodin was more effective than curcumin against both S. aureus and E. coli when the number of absorbed photons was matched. Aloe emodin reduced about 2.3 log units of S. aureus and 1.1 log units of E. coli more than curcumin. E. coli was more resistant to PDT than S. aureus. Inactivation kinetics of S. aureus and E. coli as a function of the number of absorbed photons can be described by the Weibull model with D values of 1.296 × 1017 photons/cm2 and 2.446 × 1018 photons/cm2, R2 of 0.969 and 0.968, respectively. The interrelationship between the concentration of photosensitizer, radiant fluence, and degree of bacterial inactivation could be used to determine and optimize treatment conditions of PDT processes.

Effects of Heat Treatment on Mechanical Properties of Jute Fiber–Reinforced Polymer Composites for Concrete Confinement

Some natural fibers such as jute which have high tensile strength can be applied in natural fiber-reinforced polymer (FRP). Natural cellulose fibers are hydrophilic, resulting in lower reinforcement performance. Heat treatment can reduce water content in natural fibers and possibly improve the properties of natural FRP in terms of enhancing fiber and polymer composite action. This paper presents an improvement of jute fiber–reinforced polymer (JFRP) composites by heat treatment. The heat treatment conditions (i.e., temperature and duration) were considered. Coupons of heated JFRPs were tested to investigate their tensile properties. The application of JFRP on confinement was investigated by compression tests on concrete cylinders with JFRP wrapping. The experimental results indicated that a suitable heat treatment condition of 80°C for 24 h can significantly increase the tensile strength of JFRP coupons and the compressive strength of JFRP-confined concrete. The testing results of concrete confinement can be used to validate the existing predicting equations for confined compressive strength. In addition, a new equation was proposed for the effect of heat treatment of JFRP.

A two-step approach for arsenic removal by exploiting an autochthonous Delftia sp. BAs29 and neutralized red mud.

Groundwater arsenic contamination represents a global threat to human health. Among the proposed bioremediation applications, microbial transformation of arsenite (As (III)) seems to be the most favorable approach as it can be easily coupled with several adsorption techniques, without producing lethal by-products or demanding chemical addition. This study highlights the potential contribution of a highly efficient As (III) transforming bacteria Delftia sp. BAs29 followed by the adsorption of transformed arsenate (As (V)) using neutralized red mud under suitable treatment conditions. Diverse experimental conditions elucidated (inflow As (III) concentrations, flow rate) the rate and oxidation efficiency to mediate the process. Red mud is a waste by-product from the Bayer's process of the alumina industry, which when neutralized aids the removal of As (V). The neutralized red mud was characterized using X-ray diffraction (XRD) microanalysis, Scanning electron microscopy-energy-dispersive X-ray spectroscopy (SEM-EDX) and Fourier-transform infrared spectroscopy (FTIR). Arsenate adsorption using neutralized red mud was also studied as a function of pH and time, adsorbent dosage, and initial As (V) concentration. The adsorption process was significantly affected by the solution pH, which on decreasing gradually increased the adsorption efficiency. The maximum monolayer capacity for adsorption of 274.1mg/g As (V) was found at optimum conditions of pH4.0 and a contact time of 30min at a temperature of 30°C, respectively. Furthermore, this process significantly contributed in fabricating a two-step bio-filter column for the removal of total arsenic from groundwater. Graphical abstract.

Enhanced hardness and moderate thermal conductivity of Cu-2.4Ni-0.7Si alloy processed via selective laser melting followed by suitable heat treatment

The crystallographic texture, thermal conductivity, and microhardness of the Cu-2.4Ni-0.7Si alloy processed by selective laser melting (SLM) were investigated. The SLM sample shows columnar grains with stronger (100) preferred orientation, and the content of high-angle grain boundaries (HAGBs) is 64.6%. It owns the lower microhardness of 89.73 Hv and the higher thermal conductivity of 187.83 W/m K. After heat treatment for 12 and 25 h, the microstructure of the samples changes from the coarser columnar grains to the smaller equiaxedlike grains with the HAGBs of 59.6% and 61.8%, which show (100), (101), and (111) orientations equally then exhibit stronger (101) and (111) preferred orientation. Moreover, the precipitates vary from Ni3Si with a size of 0.5 μm to Ni2Si with a size of 1 μm, hence resulting in higher microhardness of 180.02 and 170.03 Hv. Due to the precipitates, lower texture index and HAGBs’ content that generate the more grain boundary scattering for electron and phonon transport lead to lower thermal conductivity of 161.57 and 177.83 W/m K. This study suggests that thermal conductivity and microhardness of the SLM Cu-Ni-Si alloy can be tailored by controlling suitable heat treatment condition.