Heavy metal remediation of aqueous streams is of special concern due to recalcitrant and persistency of heavy metals in environment. Conventional treatment technologies for the removal of these toxic ...heavy metals are not economical and further generate huge quantity of toxic chemical sludge. Biosorption is emerging as a potential alternative to the existing conventional technologies for the removal and/or recovery of metal ions from aqueous solutions. The major advantages of biosorption over conventional treatment methods include: low cost, high efficiency, minimization of chemical or biological sludge, regeneration of biosorbents and possibility of metal recovery. Cellulosic agricultural waste materials are an abundant source for significant metal biosorption. The functional groups present in agricultural waste biomass viz. acetamido, alcoholic, carbonyl, phenolic, amido, amino, sulphydryl groups etc. have affinity for heavy metal ions to form metal complexes or chelates. The mechanism of biosorption process includes chemisorption, complexation, adsorption on surface, diffusion through pores and ion exchange etc. The purpose of this review article is to provide the scattered available information on various aspects of utilization of the agricultural waste materials for heavy metal removal. Agricultural waste material being highly efficient, low cost and renewable source of biomass can be exploited for heavy metal remediation. Further these biosorbents can be modified for better efficiency and multiple reuses to enhance their applicability at industrial scale.
Treatment of real textile wastewater by electro-Fenton method was investigated using Ti/RuO
2
electrodes. The performance of the treatment process was evaluated in terms of %chemical oxidation demand ...removal; %color removal; and energy consumed, at three electro-Fenton process parameters: current, electrolysis time and ferrous sulfate concentration. To determine the optimum operating conditions, multiple responses optimization based on Box
–
Behnken design with desirability function was used. The optimum value of parameters were found to be current= 0.32 A, time = 90 min and ferrous sulfate concentration = 0.53 mM. Box–Behnken design suggested the %chemical oxidation demand removal; %color removal; and energy consumed were 100%, 90.30% and 1.27 Wh, respectively at optimized process parameters. The predicted performance parameters agree well with the experimental data. Second-order kinetic model was fitted to the experimental data, at optimum conditions. GC–MS analysis confirmed that dye components were totally eliminated after electro-Fenton treatment of textile effluent. To determined the toxicity of the treated textile effluent bioassay analysis was performed. It was identified that the generated by-products were non-toxic in nature. The total cost to treat the 1 m
3
of real textile wastewater by electro-Fenton at optimum conditions was $ 3.13.
Dry eye disease (DED) is a complex disorder of the ocular surface with a loss of tear film homeostasis, causing an imbalance in the tear-air interface and leading to ocular discomfort, pain, and ...vision issues. Immune control issues are a primary factor in dry eye disorder's origin, progression, and management. The aim of managing DED is to reduce symptoms and improve the life quality of those affected. Despite the diagnosis, up to half of the patients do not get proper care. The scarcity of successful treatments for DED is worrisome, and it is of increasing importance to comprehend the root causes and create more effective therapies to alleviate the distress of those afflicted with the disorder. Therefore, the role of the immune system in the initiation and progression of DED has become the research focus. This paper reviews the current insight into the immune response in DED, the existing treatment methods, and ongoing research to search for better treatments.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
In the present study adsorption of Cr(VI) from aqueous solutions onto different agricultural wastes, viz., sugarcane bagasse, maize corn cob and Jatropha oil cake under various experimental ...conditions has been studied. Effects of adsorbent dosage, Cr(VI) concentration, pH and contact time on the adsorption of hexavalent chromium were investigated. The concentration of chromium in the test solution was determined spectrophotometrically. FT-IR spectra of the adsorbents (before use and after exhaustion) were recorded to explore number and position of the functional groups available for the binding of chromium ions on to studied adsorbents. SEMs of the adsorbents were recorded to explore the morphology of the studied adsorbents. Maximum adsorption was observed in the acidic medium at pH 2 with a contact time of 60
min at 250
rpm stirring speed. Jatropha oil cake had better adsorption capacity than sugarcane bagasse and maize corn cob under identical experimental conditions. The applicability of the Langmuir and Freundlich adsorption isotherms was tested. The results showed that studied adsorbents can be an attractive low cost alternative for the treatment of wastewaters in batched or stirred mode reactors containing lower concentrations of chromium.
In the present study, effect of adsorbent dose, pH and agitation speed on nickel removal from aqueous medium using an agricultural waste biomass, Sugarcane bagasse has been investigated. Batch mode ...experiments were carried out to assess the adsorption equilibrium. The influence of three parameters on the removal of nickel was also examined using a response surface methodological approach. The central composite face-centered experimental design in response surface methodology (RSM) by Design Expert Version 6.0.10 (Stat Ease, USA) was used for designing the experiments as well as for full response surface estimation. The optimum conditions for maximum removal of nickel from an aqueous solution of 50
mg/L were as follows: adsorbent dose (1500
mg/L), pH (7.52) and stirring speed (150
rpm). This was evidenced by the higher value of coefficient of determination (
r
2
=
0.9873).
The study was planned to determine the incidence and analyze how various epidemiological factors tend to be associated with delayed adverse donor reactions (ADR).
The prospective observational study ...was conducted in Department of Transfusion Medicine of tertiary care hospital from January to December 2019. Eligible blood donors were observed for any adverse reactions after 15 minutes of removal of phlebotomy needle. Further, telephonic calls were made to each enrolled blood donor on day-2 and day-7 of the whole blood donation. For each day, two calls were made at an interval of 4 hours before declaring the participant to be non-responder.
A total of 1540 (84.1%) blood donors responded on day-2 and 1610 (87.9%) responded on day-7 of follow-up. Total 180 (11.2%) blood donors experienced delayed ADRs. Two donors (1.1%) experienced on-site while 178 (98.89%) reported off-site delayed ADRs when followed-up telephonically. The commonest delayed ADRs reported were bruise (n=72; 30.9%), arm-pain (n=61; 26.2%) and generalised weakness (n=44; 18.9%). Female donors (27.3% vs. 11.2%; P=0.004), first time donors (15.2 vs. 9.9%; P=0.002), donors with low body-weight (range of 45–60kg; 15.9% vs. 11.5% vs. 6.1%; P=0.011) and body mass index<18.5 (24% vs. 12.5% vs. 9.7% vs. 11.3%; P=0.028) experienced more delayed ADRs.
Blood donors do experience delayed ADRs but these are not reported to the blood centers as these are usually mild. However, it is important to capture these delayed adverse donor reactions and report it to National Hemovigilance Program so that strategies can be formulated to prevent their occurrence and recurrence.
Aim
To identify the different antifungal biomolecules produced by isolate Bacillus vallismortis R2 and analyse their effect on Alternaria alternata, a common pathogen causing black point disease of ...wheat.
Methods and Results
The different antifungal molecules produced by isolate R2 were purified by column chromatography. The liquid chromatography‐mass spectrometry of purified fractions confirmed the ability of R2 to produce biomolecules putatively similar to three different families of cyclic lipopeptides (CLPs) viz. surfactins, iturins and fengycins. The synergistic interaction among CLPs was evident from significant increase in the antifungal activity of mixture of purified fractions as compared to that of the individual fractions by agar well diffusion assay. The evaluation of antifungal activity of purified fractions by 96‐well microtitre plate assay showed that the fengycin‐like molecules supported significantly higher antifungal activity against A. alternata than iturin A and no antifungal activity was supported by surfactin.
Conclusions
The isolate R2, producing different CLPs, can be used as an environmental friendly alternative to chemical fungicides. Among the three different CLPs viz. surfactin, iturin A and fengycin produced by R2, the fengycins were the most active lipopeptides.
Significance and Impact of the Study
This is the first report on co‐production of three different types of CLPs by the cells of B. vallismortis.
This paper reports the feasibility of using various agricultural residues viz. sugarcane bagasse (SCB), maize corncob (MCC) and Jatropha oil cake (JOC) for the removal of Cd(II) from aqueous solution ...under different experimental conditions. Effect of various process parameters, viz., initial metal ion concentration, pH, and adsorbent dose has been studied for the removal of cadmium. Batch experiments were carried out at various pH (2–7), adsorbent dose (250–2000
mg), Cd(II) concentration (5–500
mgl
−1) for a contact time of 60
min. The maximum cadmium removal capacity was shown by JOC (99.5%). The applicability of Langmuir and Freundlich isotherm suggests the formation of monolayer of Cd(II) ions onto the outer surface of the adsorbents. Maximum metal removal was observed at pH 6.0 with a contact time of 60
min at stirring speed of 250
rpm with an adsorbent dose of 20
g
l
−1 of the test solution. The maximum adsorption of cadmium (II) metal ions was observed at pH 6 for all the adsorbents viz; 99.5%, 99% and 85% for JOC, MCC, and SCB, respectively. Order of Cd(II) removal by various biosorbents was JOC
>
MCC
>
SCB. JOC may be an alternative biosorbent for the removal of Cd(II) ions from the aqueous solution. FT-IR spectra of the adsorbents (before use and after exhaustion) were recorded to explore number and position of the functional groups available for the binding of Cd(II) ions on to studied adsorbents. These results can be helpful in designing a batch mode system for the removal of cadmium from dilute wastewaters.
Abstract
In the current study, various thermodynamic and acoustical properties have been analyzed using density (
ρ
) and ultrasonic velocity (u) of liquid mixture aqueous glutaraldehyde with EG, DEG ...and TEG. It is carried out at different temperatures (293.15, 298.15, 303.15 and 308.15 K) and concentrations (0.01, 0.02, 0.03 and 0.04 mol.kg
−1
). Values of acoustic impendence (Z), adiabatic compressibility (β) and intermolecular free length (L
f
) are calculated with the help of given velocity and density data. Adiabatic compressibility and intermolecular free length decreased with the rise in concentration, indicating weak interaction between the molecules of the mixture. Acoustic impedance varies linearly as concentration increases, indicating the absence of complex formation.
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