High-Performance Material for the Effective Removal of Uranyl Ion from Solution: Computationally Supported Experimental Studies.

Adsorption is a widely used method for pollution removal and for the recovery of valuable species. In recent years, the use of metal-organic compounds among the adsorbents used in adsorption studies has increased. In this study, the performance of the water-insoluble Fe complex as a metal organic framework (MOF-Fe-Ta) of water-soluble tannic acid, which is not used as an adsorbent in uranium recovery and removal, was investigated. For the characterization of the new synthesized material, Fourier transform infrared, scanning electron microscopy, and X-ray diffraction analyses were performed. The changes in the adsorption process based on various parameters were investigated and discussed. The point of zero charges value of the adsorbent was found as 5.52. It was noticed that the adsorption increases as the pH increases. Analyzing the effect of concentration on adsorption, we determined which model explained the adsorption better. The monolayer capacity of the adsorbent determined in light of the Langmuir model was reported as 0.347 mol kg-1. The Freundlich constant, namely the ß value obtained in the Freundlich model, which is a measure of surface heterogeneity, was found to be 0.434, and the EDR value, which was found from the Dubinin-Raduskevich model and accepted as a measure of adsorption energy, was 10.3 kJ mol-1. The adsorption was kinetically explained by the pseudo-second-order model and the adsorption rate constant was reported as 0.15 mol-1 kg min-1. The effect of temperature on adsorption was studied; it was emphasized that adsorption was energy consuming, that is, endothermic and ΔH was found as 7.56 kJ mol-1. The entropy of adsorption was positive as 69.3 J mol-1 K-1. As expected, the Gibbs energy of adsorption was negative (-13.1 kJ mol-1 at 25 °C), so adsorption was considered as a spontaneous process. Additionally, the power and mechanism of the interaction between studied adsorbent and adsorbate are explained through density functional theory computations. Computationally obtained data supported the experimental studies.

Synthesis and characterization of chitosan-vermiculite-lignin ternary composite as an adsorbent for effective removal of uranyl ions from aqueous solution: Experimental and theoretical analyses.

Chitosan (Ch), vermiculite (V) and lignin (L) were used as the components of a natural composite adsorbent (Ch-VL) for the removal of the UO22+ ions in aqueous solutions. During the study, we recorded and analyzed the initial UO22+ ion concentration, initial pH, contact time, temperature, and recovery. The recycling performance of the Ch-VL composite was assessed by three sequential adsorption/desorption experiments. Adsorption performance of the Ch-VL composite for UO22+ ions was 600 mg L-1 at pH 4.5 and temperature of 25 °C. Thermodynamic findings, ΔH0:28.1 kJ mol-1, and ΔG0:-14.1 kJ mol-1 showed that adsorption behavior was endothermic and spontaneous. Its maximum adsorption capacity was 0.322 mol kg-1, obtained from the Langmuir isotherm model. The adsorption kinetics indicated that it followed the pseudo-second-order and intraparticle diffusion rate kinetics. The adsorption thermodynamic shown indicated that the UO22+ ion adsorption was both spontaneous and endothermic. The adsorption process was enlightened by FT-IR and SEM-EDX analyses. The study suggested a simple and cost-effective approach for the removal of toxic UO22+ ions from wastewater. To highlight the adsorption mechanism, DFT calculations were performed. Theoretical results are in good agreement with experimental observations.

A combined molecular dynamic simulation, DFT calculations, and experimental study of the eriochrome black T dye adsorption onto chitosan in aqueous solutions.

This study aims to evaluate and understand the adsorption of eriochrome black T (EB) by chitosan extracted from local shrimp shells under different experimental conditions. Chitosan samples were characterized by XRD, SEM, and FTIR. Experimental results indicate that the process was pH-dependent with a high adsorption capacity in acidic medium. The adsorption was rapid and kinetic data were suitably correlated to the pseudo-second-order kinetic model. EB molecules were adsorbed on monolayer according to the Langmuir model with an adsorption capacity of 162.3 mg/g. On the other hand, it should be noted that calculated quantum chemical parameters support the experimentally obtained results. The interaction energies calculated for (molecule/chitosan) complexes were in the order of H2EB- > HEB2- (O38) > HEB2- (O48) > EB > H3EB > EB3-, which means that the best and possible adsorption process can take place with H2EB- form. The molecular dynamics (MD) approach was performed to illuminate the nature of the relationship between the EB and the chitosan (110) surface. It was found that the chitosan (110) surface adsorbs EB molecule in a nearby parallel orientation. The higher negative adsorption energy determined for the H2EB- implies that the adsorption mechanism is the typical chemisorption.

Poly(styrene)-co-2-vinylpyridine copolymer as a novel solid-phase adsorbent for determination of manganese and zinc in foods and vegetables by FAAS.

The aim of this study is to extract zinc and manganese from foods and vegetables using an amphiphilic copolymer adsorbent, poly(styrene)-co-2-vinylpyridine which was synthesized via reversible addition fragmentation chain transfer (RAFT) polymerization from styrene and 2-vinyl pyridine in the presence of a trithiocarbonate and 2,2'-azo-bis isobutyro nitrile (AIBN) in toluene solution under argon at 80 °C. Fourier Transform Infrared (FTIR) and proton nuclear magnetic resonance (1H NMR) spectroscopy were used in the characterization of the obtained copolymer. Under the optimum conditions, several validation variables such as uncertainty measurement, selectivity, robustness, precisions, matrix effects and accuracy were investigated. Taking an adsorption time of 15 min, detection limits of 0.04 µg L -1 and 0.2 µg L-1and 7.9 µg L-1and enrichment factors of 145 and 110 were obtained for Mn(II) and Zn(II), respectively.The method was successfully applied to the analysis of Mn(II) and Zn(II) in foods and vegetables.

Removal of food dyes from aqueous solution by chitosan-vermiculite beads.

In this study, Chitosan (Ch)-Vermiculite (V) composite beads material which is a low-cost and naturally effective adsorbent were used for efficient removal of Sunset Yellow FCF (Sy) and Brilliant Blue FCF (Bb) food dyes from aqueous solution. Ch-V composite beads were characterized by using FTIR, SEM, XRD and PZC analysis. The adsorbent properties of Ch-V composite beads for Sy and Bb dyes were evaluated in terms of pH, concentration, kinetic (time) and thermodynamic (temperature) of adsorption. The experimental data presented were obtained from Langmuir, Freundlich and Dubinin-Radushkevich (DR) isotherm models. The maximum adsorption capacity for the Langmuir equation was found to be 0.387 mol kg-1 for Sy and 0.229 mol kg-1 for Bb, respectively. The results showed that the experimental data were better fit the Langmiur model for Sy and the Freundlich model for Bb. Adsorption energies obtained from DR model for Sy and Bb showed that adsorption processes were chemically. The pseudo-second order and intra-particle diffusion models of adsorption kinetics are in accordance with Sy and Bb. As a result of thermodynamic evaluation of Sy and Bb adsorption, it was found that adsorption processes were endothermic, entropy increased and reaction was spontaneous.

Assessment of Pb2+ removal capacity of lichen (Evernia prunastri): application of adsorption kinetic, isotherm models, and thermodynamics.

Biological materials play a significant role in the treatment of heavy metal-contaminated soil and wastewater. In this study, the Pb2+ biosorption potential of lichen Evernia prunastri, extensively available at a forest in Bilecik-Turkey, was investigated at batch-scale level. The optimal conditions were determined and the adsorption isotherms, kinetics, and thermodynamic calculations were also done. In order to have detailed knowledge about metal biosorption, SEM, FTIR, and BET analyses were carried out before and after the biosorption process. The optimal pH was found pH 4 and the maximum metal uptake capacity was found as 0.067 mol kg-1. The results of this study indicate that the lichen was effectively applied to the removal of Pb2+ process as an inexpensive biosorbent from industrial wastewater.

Effective UO22+ removal from aqueous solutions using lichen biomass as a natural and low-cost biosorbent.

The UO22+ biosorption properties of a lichen, Evernia prunastri, from aqueous solutions were investigated. The widely occurring lichen samples were collected from the forest in Bilecik-Turkey. The UO22+ biosorption onto lichen was characterized by FT-IR and SEM-EDX analysis techniques before and after biosorption. The effects of the solution pH, biosorbent dosage, UO22+ concentration, contact time, and temperature on UO22+ biosorption on lichen sample were studied by using the batch method. The isotherm experimental data were described using isotherm models of Langmuir, Freundlich and Dubinin Radushkevich. The maximum UO22+ biosorption capacity of the lichen sample was estimated by the Langmuir equation to be 0.270 mol kg-1. The adsorption energy from the Dubin Radushkevich model was found to be 8.24 kJ mol-1. Kinetic data determined that the biosorption was best described by the pseudo-second-order kinetic model. Thermodynamic findings showed that the biosorption process was endothermic, entropy increased and spontaneous. In conclusion, the lichen appears to be a promising biosorbent for the removal of UO22+ ions from aqueous solutions because of high biosorption capacity, easy usability, low cost, and high reusability performance.

Synthesis and characterization of a composite polymeric material including chelating agent for adsorption of uranyl ions.

In this study, a versatile polymeric material was synthesized by grafting Calcon Carboxylic Acid (CCA), which is known as a chelating agent for some metal ions, to polyacrylamide (PAA) structure. Thus, the adsorptive properties of inert PAA polymer were significantly improved owing to this procedure. The obtained new material, CCA-g-PAA, was characterized by point zero charge (PZC), FTIR, SEM, and UV-VIS-NIR analysis. The adsorption properties of new material were investigated comprehensively and experimental variables were optimized such as pH, temperature, time, and concentration. Experimental data were evaluated by using theoretical adsorption models. The maximum adsorption capacity of material was calculated as 0.079molkg-1 by considering Langmuir equation. The constants calculated from Freundlich and DR model were found as 6.98 and 0.441, respectively. Adsorption kinetic was also explained with pseudo second order and intra particular diffusion models. Experimental studies were showed that adsorption was endothermic and occurred spontaneously. The developed material has important advantages such as reusability, cost-effective synthesis procedure, high adsorption capacity, and selectivity.

Comparison of intra-articular bupivacaine-morphine with bupivacaine-tenoxicam combinations on post-operative analgesia in patients with arthroscopic meniscectomy: a prospective, randomised study.

AIM: There are many alternatives for post-operative pain relief in patients who have had general anaesthesia. The aim of this study was to evaluate the efficacy of intra-articular bupivacaine + morphine and bupivacaine + tenoxicam applications in post-operative pain control in patients undergoing knee arthroscopy with general anaesthesia. METHOD: This was a prospective study. Standard anaesthesia procedures were applied to each patient, and the 240 patients chosen at random were then divided into two groups. Each group received a different combination of drugs for this double-blind study. The first group (group A: 120 patients) received 0.5% bupivacaine 100 mg + tenoxicam 20 mg (22 ml); the second group (group B) received 0.5% bupivacaine 100 mg + morphine 2 mg (22 ml); both groups received their drugs at the end of the intra-articular operation before tourniquet deflation. Before the operation, patients were asked about their post-operative pain at particular periods over the following 24 hours using the visual analogue scale (VAS) and the numeric rating scale (NRS). An additional analgaesic requirement and possible side effects were also recorded. RESULTS: Group A patients needed analgaesics sooner after operation than patients in group B. In Group B, VAS and NRS values were statistically higher compared with group A at the 12th hour. There were also fewer side effects seen in group A versus group B. CONCLUSION: Effective and reliable results were obtained in post-operative pain control in bupivacaine added to the morphine or tenoxicam groups following arthroscopic meniscectomy. In the tenoxicam group, patients reported less pain, fewer side effects and less need for analgesics at 12 hours after the operation. LEVEL OF EVIDENCE: level 1, therapeutic, randomised, multicentric study.

Insufficiency of bone scintigraphy in vertebral lesions of langerhans cell histiocytosis compared to f-18 fluorodeoxyglucose positron emission tomography/computed tomography and diagnostic computed tomography.

Langerhans cell histiocytosis (LCH) is a benign disorder related to the histiocytes which can infiltrate bone tissue. The most effective method for demonstrating severity of this disease is PET/CT and bone scintigraphy might show bone lesions. We present a seventeen year old male patient with disseminated LCH presented with exophtalmos and having multiple vertebral lesions which were identified by F-18 FDG PET/CT scan and diagnostic CT but not in the bone scintigraphy.

The comparison of single incision laparoscopic cholecystectomy and three port laparoscopic cholecystectomy: prospective randomized study.

PURPOSE: Laparoscopic techniques have allowed surgeons to perform complicated intra-abdominal surgery with minimal trauma. Single incision laparoscopic surgery (SILS) was developed with the aim of reducing the invasiveness of conventional laparoscopy. In this study we aimed to compare results of SILS cholecystectomy and three port conventional laparoscopic (TPCL) cholecystectomy prospectively. METHODS: In this prospective study, 100 patients who underwent laparoscopic cholecystectomy for gallbladder disease were randomly allocated to SILS cholecystectomy (group 1) or TPCL cholecystectomy (group 2). Demographics, pathologic diagnosis, operating time, blood loss, length of hospital stay, complications, pain score, conversion rate, and satisfaction of cosmetic outcome were recorded. RESULTS: Forty-four SILS cholesystectomies (88%) and 42 TPCL cholecystectomies (84%) were completed successfully. Conversion to open surgery was required for 4 cases in group 1 and 6 cases in group 2. Operating time was significantly longer in group 1 compared with group 2 (73 minutes vs. 48 minutes; P < 0.05). Higher pain scores were observed in group 1 versus group 2 in postoperative day 1 (P < 0.05). There was higher cosmetic satisfaction in group 1 (P < 0.05). CONCLUSION: SILS cholecystectomy performed by experienced surgeons is at least as successful, feasible, effective and safe as a TPCL cholecystectomy. Surgeons performing SILS should have a firm foundation of advanced minimal access surgical skills and a cautious, gradated approach to attempt the various procedures. Prospective randomized studies comparing single access versus conventional multiport laparoscopic cholecystectomy, with large volumes and long-term follow-up, are needed to confirm our initial experience. (ClinicalTrials.gov Identifier: NCT01772745.).

Removal of uranyl ions in aquatic mediums by using a new material: gallocyanine grafted hydrogel.

A new material containing gallocyanine (GC) grafted polyacyril amide (PAA) was synthesized and its adsorption ability was examined for the removal of uranyl ions from aqueous media. The new developed adsorbent was characterized by FTIR, SEM, and PZC analysis. Adsorption of UO2(2+) ions from aqueous solution as a function of ion concentration, pH, ionic strength, temperature, and reusability of adsorbent was investigated in detail. The adsorption data were analyzed by using the Langmuir, Freundlich and Dubinin-Radushkevich (DR) models. The adsorption of UO2(2+) increased with pH and reached a plateau value in the pH range 5-6. The adsorption of UO2(2+) ions were not affected by increasing ionic strength. The adsorption mechanism followed an endothermic and spontaneous process with increased disorderliness at adsorbate/adsorbent interface. The adsorption process followed a pseudo-second-order kinetics. The new developed material is a potential adsorbent for effective removal of uranyl ions from aquatic solutions.

Hanging-induced burst suppression pattern in EEG.

Lethal suspension (hanging) is one of the most common methods of attempting suicide. Spinal fractures, cognitive and motor deficits as well as epileptic seizures can be detected after unsuccessful hanging attempts. Introduced here is the case of a 25-year-old man exemplifying the clinical observations stated hereafter, who was conveyed to our emergency room after having survived attempted suicide by hanging, with his post-anoxic burst-suppression electroencephalography (BS-EEG) pattern and clinical diagnoses in the post-comatose stage. The patient's state of consciousness was gradually improved over a period of time. His neuropsychiatric assessment proved that memory deficit, a slight lack of attention and minor executive dysfunction was observed a month after the patient was discharged. Although the BS-EEG pattern indicates severe brain dysfunction, it is a poor prognostic factor; rarely, patients survive with minor cognitive deficits and can perform their normal daily activities.

Combination of pharmacotherapy with electroconvulsive therapy in prevention of depressive relapse: a pilot controlled trial.

OBJECTIVE: Relapse rates after electroconvulsive therapy (ECT) remain high with standard treatments. We aimed to test the efficacy of an early administered continuation pharmacotherapy (c-pharm early) strategy in prevention of post-ECT relapse. METHOD: A 20-week, randomized, double-blind, placebo-controlled trial. Patients aged 18 to 65 years diagnosed with Diagnostic and Statistical Manual of Mental Disorders major depressive disorder, with or without psychotic features, with initial Montgomery-Asberg Depression Rating Scale scores higher than 22, underwent 8 bilateral ECT sessions (2 per week). Randomization to c-pharm early, c-pharm late, and placebo groups in 2:2:1, respectively, was performed at the completion of the fourth ECT session. After randomization, subjects in the c-pharm early group were given sertraline at 150 mg/d. Subjects in the c-pharm late group were first given placebo, which was substituted with sertraline at 150 mg/d at the completion of the eight ECT. Relapse was defined as a Montgomery-Asberg Depression Rating Scale score of 16 or higher. RESULTS: Seventy-three percent of the patients responded to the given treatment. The relapse rates were 12.5% in the c-pharm early group, 28% in the c-pharm late group, and 67% in the placebo group (P = 0.09). The c-pharm early strategy resulted in significantly lower relapse rates and longer well time compared with the placebo (P = 0.04). When the trend with the initiation of the c-pharm intervention was investigated in the 3 groups with equally spaced trend weights, the time of initiation was found to have a significant effect on the probability of the remaining well (P = 0.03). CONCLUSIONS: Comparative efficacy of c-pharm early and late strategies in providing improved protection against post-ECT relapse of major depressive disorder needs to be further explored.

Lead removal by polyacrylamide-bentonite and zeolite composites: effect of phytic acid immobilization.

Polyacrylamide (PAA)-bentonite (B) and zeolite (Z) composites were prepared by direct polymerization of PAA in suspensions of B and Z. Phytate (Phy) immobilized onto the composites to obtain their Phy modifications. FT-IR and XRD were employed to characterize their structures. The sorption of Pb(2+) from various adsorption media onto the composites was then investigated. The reusability and storage characteristics of the adsorbents with and without Phy were also considered for Pb(2+) adsorption. All isotherms were L and H type of the Giles classification. The Phy adsorption capacities (X(M)) of PAA-B and Z lower than those of bare B and Z due to their surface coverage by PAA. The Phy modification decreased the Pb(2+) adsorption capacities of B and PAA-B but ascended those of Z and PAA-Z. However, Phy significantly increased the Langmuir equilibrium constants (K(L)) for all adsorbents. Ionic strength of the adsorption media was favorable for the adsorption capacity of PAA-B while not for that of PAA-Z. The chemical structure of the composites was not changed after five reuses and the storage foregoing. It is foreseen that the use of PAA-B and PAA-Z and their Phy modifications will provide practicality and effectiveness for Pb(2+) separation and removal procedures. The X(M) (mol kg(-1)) and K(L) (L mol(-1)) values for Pb(2+) adsorption from a model solution were 0.16 and 3625 for PAA-B, 0.18 and 5.1 x 10(5) for PAA-B-Phy, 0.28 and 13210 for PAA-Z and 1.65 and 2.0 x 10(5) for PAA-Z-Phy.