Synthesis and characterization of sufficiently pure magnetic nanoparticles in the range 8.3–23.0
nm using ferric iron recovered from waste iron ore tailings for their use as nanoadsorbents have been ...described.
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► Synthesis of magnetite nanoparticles using ferric iron recovered from waste iron ore tailings. ► Superparamagnetic behavior and good dispersibility of magnetic nanoparticles. ► Fast and efficient adsorptive removal of dyes by magnetite nanoparticles. ► Input for alternative utilization of waste iron ore tailings. ► Approach of synthesis of magnetite nanoparticles from waste.
The ferric iron recovered from waste iron ore tailings (IOTs) via acid leaching and precipitation to iron (hydr)oxide was used to synthesize magnetite nanoparticles (MNPs) by coprecipitation of its aqueous acidic solution along with ferrous iron under inert atmosphere. The electrostatically stabilized MNPs showed super paramagnetic behavior and good dispersibility in aqueous medium with high stability. Powder XRD, UV–Vis and FT-IR spectra confirmed the formation of single phase magnetite. The scanning and transmission electron micrographs revealed that the MNPs were spheroidal or cubic in shape with size ranging from 8.3 to 23.0
nm. The MNPs were found effective for fast adsorptive removal of both cationic (methylene blue) and anionic (Congo red) dyes from their aqueous solutions. Under optimized condition, the maximum monolayer adsorption capacities were found to be 70.4
mg
g
−1 and 172.4
mg
g
−1 for methylene blue and Congo red, respectively. Moreover, the present study addressed a feasible alternative use of waste IOT to synthesize a value added product for its possible large scale application in treatment of wastewaters.
One of the major objectives of modern supply chain management is dealing with the negative impact of decentralization among the involved entities and minimizing double marginalization effect within ...the chain, especially when the end-customers’ demand is not deterministic. This paper investigates coordination issue in a three-level supply chain with one raw-material supplier, one manufacturer, and one retailer. The retailer determines the retail price, sales effort, and order quantity simultaneously before the selling season starts. Both the supplier and the manufacturer face random yield in production. A composite contract having two components—a contingent buyback with target sales rebate and penalty between the retailer and the manufacturer, and a revenue sharing contract between the manufacturer and the supplier is proposed. The proposed composite contract is shown to achieve supply chain coordination and allows arbitrary allocation of total channel profit among all the chain members. The impact of randomness in both demand and production, and the impact of non-existence of emergency resource for the final product on the performance of the entire supply chain are analyzed. A numerical example is provided to illustrate the developed model and draw some important managerial insights.
Amniotic fluid cells (AFCs) are obtained from amnion for pre‐natal analysis and can be cultured in vitro. Heterogeneous amniotic fluid (AF) contains various cell types, and it is believed that some ...of these cells possess the stem cell properties. The aim of this study was to characterize these cells by phenotypical and genotypical means in buffalo. The differentiation potential of amniotic fluid stem (AFS) cells was carried out by converting these cells into neurons. The AFCs were cultured without feeder cells in DMEM containing 16% foetal bovine serum, 1% penicillin/streptomycin and 1%l‐glutamine in 5% CO2 at 38.5 ± 0.5°C in a CO2 incubator. After 6 days of culture, different types of cells viz., star shaped (62.7%), spherical without nucleus (1.9%), spherical with nucleus (26.4%), pentagonal (0.4%) and free floating/rounded cells (8.3%) were observed. Most of the cells started anchorage‐dependent growth after day 7 of the culture. Expression of Oct‐4, Sox‐2, Nanog, alkaline phosphatase, 18s rRNA, stem cell factor, cyclin A, Nestin and FGF‐5 was observed from the AFS cells in different passages with PCR amplicon of 314, 277, 317, 180, 162, 216, 421, 307 and 210 bp, respectively. During the differentiation step, at day 6, neuron‐like cells could be clearly identified and confirmed with Nestin‐specific RT‐PCR. The cells were found to have a normal karyotype at different passages. These results may contribute towards establishing non‐embryonic pluripotent stem cells for various therapeutic and reproductive biotechnological applications in the species.
ABSTRACT
We investigate systematic effects in direction-dependent gain calibration in the context of the Low-Frequency Array (LOFAR) 21-cm Epoch of Reionization (EoR) experiment. The LOFAR EoR Key ...Science Project aims to detect the 21-cm signal of neutral hydrogen on interferometric baselines of 50–250 λ. We show that suppression of faint signals can effectively be avoided by calibrating these short baselines using only the longer baselines. However, this approach causes an excess variance on the short baselines due to small gain errors induced by overfitting during calibration. We apply a regularized expectation–maximization algorithm with consensus optimization (sagecal-co) to real data with simulated signals to show that overfitting can be largely mitigated by penalising spectrally non-smooth gain solutions during calibration. This reduces the excess power with about a factor of 4 in the simulations. Our results agree with earlier theoretical analysis of this bias-variance trade off and support the gain-calibration approach to the LOFAR 21-cm signal data.
In the present investigation, the Kuzi ducks of Odisha were studied with respect to different phenotypic traits and genetic parameters measured for Juvenile traits from 1,718 ducklings hatched in ...three hatches using 40 sires and 160 dams reared under standard management conditions. Fertility, hatchability, juvenile traits, body weight gains and plumage characteristics were recorded. Carcass characteristics of the drakes were also measured at 20 weeks of age. The average fertility was 75.42% and hatchability on total egg set and fertile egg set basis were 61.79 and 82.10%, respectively. The body weight between male and female showed sexual dimorphisms with respect to body weight and conformation traits from 4th week onwards in Kuzi ducks. The least square body weight recorded at 8 weeks of age in male, female and pooled over sexes were 1,388, 1,231 and 1,282 g, respectively. Heritability estimates for different juvenile traits were moderate to high in magnitude for the traits studied. Body weight recorded at 20 weeks of age was 1,818 g in male and 1,628 g in female. Total edible carcass yield was 76.48% at 20 weeks of age in male. Multi-colour is found to be dominant plumage colour. The study revealed that Kuzi ducks of Odisha have very good potential for duck farming in the country and the body weight of the duck may be improved by selection of the birds and the drake (male) may be used for meat purpose. The growth of the ducklings was very fast from 2 to 8 weeks of age.
•Low pH is a major factor that restricts growth and stability of probiotic bacteria.•Molecular oxygen is detrimental to growth and survival of probiotics especially during storage period.•The process ...of microencapsulation has been used for improving the viability of probiotics in fermented food products.•Antioxidant compounds could be used to limit negative effects of oxygen exposure on probiotic bacteria.•Mild heat treatment before spray drying may enhance cell survival during storage.
Probiotic foods are reported to provide several health benefits, as they help in maintaining a good balance and composition of intestinal flora, and increase the resistance against invasion of pathogens. The demand of probiotic functional foods is growing rapidly due to increased awareness of consumers about the impact of food on health. Development of foods with adequate doses of probiotics at the time of consumption is a challenge, because several factors during processing and storage affect the viability of probiotic organisms. The presence of probiotics in food products may also adversely affect their quality and sensory properties. Several attempts have been made during the last few decades to improve the viability of probiotics in different food products during their production until the time of consumption. Major emphasis has been given to protect the microorganisms with the help of encapsulation technique, by addition of different protectants, and by alteration of processing and storage conditions. This contribution provides an overview of probiotic foods, factors responsible for survival of probiotics, and advance technologies used to stabilize their viability during processing and storage.
(a) Magnetic field and particle size dependent TC of nanometric (black and red dot) and bulk (blue and wine dot) measured upon cooling (full dots) and warming (open dots). (b) Temperature dependence ...magnetic entropy change ΔS at different magnetic field calculated from the magnetization data of S1250 bulk sample. Display omitted
•Large magnetocaloric effect is reported based on the first order phase transition.•The value of |ΔSM| reaches a maximum value of 8.48J/kgK at 60kOe field.•A large relative cooling power (∼574J/kg) around TC–172K is reported.•The adiabatic temperature change is found to be 2.38K for magnetic field of 10kOe.•Noticeable |ΔSM| at low field makes the system useful for magnetic refrigeration.
This paper reports about the magnetocaloric effect and relative cooling power based on the first order magnetic phase transition in Sm0.55Sr0.45MnO3 polycrystalline phase separated manganites. Upon 60kOe applied magnetic field, the magnetic entropy change (|ΔSM|) of bulk sample reaches a maximum value of 8.48J/kg-K with a large relative cooling power (RCP) value of 574J/kg around its Curie temperature (TC)–172K after the correction for hysteretic losses caused by the first order magnetic phase transition. The corresponding adiabatic temperature change is 2.38K for magnetic field of 10kOe. The magnetic field induced change of entropy and specific heat vary with temperature and have their maximum around the first order magnetic phase transition. We also report the magnetic field dependence of the order of the ferromagnetic (FM) to paramagnetic (PM) phase transition in bulk and nanometric manganites. It has been shown that bulk to nanometric samples exhibit first order FM→PM phase transition under low magnetic field accompanied by magnetization with thermal hysteresis in the field cooled cooling and warming cycle. However, the samples exhibit a second order magnetic phase transition above a critical field HCR. All the signatures of the first-order magnetic phase transition in bulk and nanometric sample disappear above the critical field HCR. The magnetocaloric effect is thus modified by the field induced order of magnetic phase transition. The field induced paramagnetic to ferromagnetic transition is confirmed to be first order in nature from dc magnetization measurements and Arrott plots using a criteria given by Banerjee. The magnetic phase transition is also accompanied by a large change in resistivity with thermal hysteresis. The observed value of magnetic entropy change in bulk sample is much higher than the value generally observed in other perovskite manganites of comparable TC. This large change mainly originates from a sharp magnetization jump, associated with a first-order metamagnetic transition and coalescence of ferromagnetic clusters in the paramagnetic state. Such noticeable magnetic entropy change at low magnetic field makes this material useful for the application of active magnetic refrigerant (AMR) materials.
The paper develops integrated production, inventory and maintenance models for a deteriorating production system in which the production facility may not only shift from an ‘in-control’ state to an ...‘out-of-control’ state but also may break down at any random point in time during a production run. In case of machine breakdown, production of the interrupted lot is aborted and a new production lot is started when the on-hand inventory is depleted after corrective repair. The process is inspected during each production run to examine the state of the production process. If it is found in the ‘in-control’ state then either (a) no action is taken except at the time of last inspection where preventive maintenance is done (inspection policy-I) or (b) preventive maintenance is performed (inspection policy-II). If, however, the process is found to be in the ‘out-of-control’ state at any inspection then restoration is done. The proposed models are formulated under general shift, breakdown and repair time distributions. As it is, in general, difficult to find the optimal production policy under inspection policy-I, a suboptimal production policy is derived. Numerical examples are taken to determine numerically the optimal/suboptimal production policies of the proposed models, to examine the sensitivity of important model parameters and to compare the performance of inspection and no inspection policies.
Soymilk is the aqueous extract of whole soybeans, resembling dairy milk in physical appearance and composition. The basic steps of its preparation include selection of soybeans, soaking in water, wet ...grinding, separation of soymilk from fiber (okara), cooking to inactivate lipoxygenase and trypsin inhibitors, formulation and fortification, and packaging. The properly processed soymilk and its derivatives offer many neutraceutical and health benefits. The type of processing and ensuing processing conditions such as high or low temperatures, short or prolonged temperature and cooking time, ultra high temperature, spray-drying parameters, processing treatment combinations with alkali or other chemicals etc. affect the properties of soymilk. The present article focuses on various processing aspects like soaking, blanching, heat treatments, chemical and enzyme treatments, fermentation, homogenization, filtration, spray-drying etc., and their effects on the composition, anti-nutrients, physico-chemical properties, sensory attributes, microbial load, and shelf-life of liquid and powdered soymilk. The applications of some novel techniques such as high-pressure processing, pulsed electric field, ultra high-pressure homogenization, ultrasound, and membrane separations on soymilk processing are also discussed.
Biodegradable polymeric nanostructures (BPNs) have shown great promise in different therapeutic applications such as diagnosis, imaging, drug delivery, cosmetics, organ implants, and tissue ...engineering. BPNs exhibit superior properties over their respective bulk materials, overcoming the limitations of traditional polymers to address numerous important medical problems. Furthermore, the addition of other components can enable specific functionalities of the nanostructures to be modulated for tunable applications. This review emphasizes the state-of-the-art of biodegradable polymeric nanostructures, preparative methods, therapeutic uses, and challenging issues concerning the commercialization of emerging BPN-based therapeutics with respect to their future perspectives.
Biodegradable polymeric nanostructures (BPNs) have shown great promise in different therapeutic applications such as diagnosis, imaging, drug delivery, cosmetics, organ implants, and tissue engineering.
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