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Current COVID-19 effects are forcing us to think about other deadly viral diseases. Respiratory syncytial virus (RSV) is one of them. Every year thousands of children lost their lives due to respiratory diseases which are occurred by this RSV. Nowadays, bioactive compounds show an enormous effect on many deadly diseases and show excellent therapeutic effects. In this study, we have identified five bioactive compounds from the plant which will be used in the treatment of RSV. Molecular docking on the protein was done by Autodock. Hydrogen was added and routable bonds were fixed in the preparation time of protein for docking. All those compounds show their non-toxic nature which is evaluated by Lipinski's Rule of Five. Molecular docking on RSV matrix protein and surface glycoprotein with those bioactive compounds shows very promising results. Between all those compounds Baicalein appears as a lead compound. It shows -8.1 Kcal/mol in the case of matrix protein and -7.9 kcal/mol in the case of the surface glycoprotein of RSV. Due to its availability and non-toxic nature, it can be used in the treatment of RSV. AS it is derived from plants, it also has very fewer side effects than chemical drugs.

The flow separation zone (FSZ) is one of the main flow characteristics of the combining open channel junction and is associated with energy dissipation. Bed shear stress in the contracted f...

Leishmaniasis is a zoonotic disease transmitted in humans by the bite of Leishmania-infected phlebotomine sandflies. Each year approximately 58,500 cases of leishmaniasis are diagnosed across the globe, with a mortality rate of nearly seven percent. There are over 20 parasitic strains of Leishmania which are known to cause distinct types of leishmaniasis and pose an endemic threat to humans worldwide. Therefore, it is crucial to develop potential medications and vaccines to combat leishmaniasis. However, the task of developing therapeutic solutions is challenging due to Leishmania’s digenetic lifecycle. The challenge is further intensified by cases of resistance against the available drugs. Owing to these challenges, the conventional drug development regimen is further limited by target discovery and ligand suitability for the targets. On the other hand, as an added advantage, the emergence of omics-based tools, such as high-end proteomics, transcriptomics and genomics, has hastened the pace of target discovery and target-based drug development. It is now becoming apparent that multi-omics convergence and an inter-connected systems approach is less time-consuming and more cost-effective for any drug-development process. This comprehensive review is an attempt to summarize the current knowledge on the muti-omics approach in drug development against leishmaniasis. In particular, it elaborates the potential target identification from secreted proteins in various stages of Leishmania infection and also illustrates the convergence of transcriptomic and genomic data towards the collective goal of drug discovery. This review also provides an understanding of the potential parasite’s drug targets and drug resistance characteristics of the parasite, which can be used in designing effective and specific therapeutics.

The radiation stability of two extraction chromatography resins containing diglycolamide ligands viz. TPDGA (N,N,N',N'-tetra-n-pentyl diglycolamide) and TODGA (N,N,N',N'-tetra-n-octyl diglycolamide) in a room temperature ionic liquid (C

The potentials of natural fibre encourage researchers to shift their interest from synthetic fibre. Numerous works have been done on the effective use of several natural fibres in manufacturing composites for automotive and structural applications. In the current investigation, effort has been made to evaluate the effect of the addition of glass fibre and influence of stacking sequence on mechanical properties of kenaf-/glass-reinforced hybrid composite laminates. Hybrid laminates with five different stacking sequences were fabricated by using hand layup technique. After curing, the fabricated composite laminates were cut to the dimension as per ASTM standard. Different tests have been carried out to determine tensile strength, flexural strength, and micro-hardness of fabricated laminates. Based on the findings, a sharp increase in mechanical properties is observed due to addition of glass fibre. Laminate with four layers of kenaf fibre shows minimum values of tensile strength, flexural strength and micro-hardness values. On subsequent addition of glass layer to the laminates, an increase in tensile strength from 35.78 to 166.38 MPa, flexural strength from 42.91 MPa to 155.83 MPa and micro-hardness value from 11.51 to 20.84 HV are reflected. To validate the experimental findings, numerical analysis has been made by using ANSYS R19.0 software. On comparison of experimental and numerical values, the deviation of the result is limited to 3%–12%. The morphology of fracture surfaces is also studied by using scanning electron microscope.

Bis-octyloxy-calix[4]arene-mono-crown-6 (BOCMC) is a selective ligand for Cs(I) cation, and has been used in solvent extraction method for its separation from acidic feed. Looking at the various advantages and ease of extraction chromatography separation method, an attempt was made to prepare stable composite beads containing BOCMC entrapped in a suitable polymeric matrix. Therefore, an attempt was made to prepare a series of composite polymeric beads containing BOCMC in polysulfone (PS), polyether sulfone (PES) and sodium alginate polymeric matrix. Preparations of the beads were attempted by dissolving the solid BOCMC in the polymer solution, and also by using the ligand solution in isodecanol/dodecane and ionic liquids and then mixing in the polymeric solution. Every attempt failed to get the desired quality of beads in PES and sodium alginate matrix. However, very good quality and stable beads were obtained when 25 mM ligand solution dissolved in C

Two benzene-centered tripodal diglycolamide ligands (LI and LII) were used for the extraction of Am3+ and Eu3+ from nitric acid solutions into a diluent medium of n-dodecane modified with various amounts of isodecanol. The ligands showed preferential extraction of Eu3+ over Am3+ in most cases. While the extraction of the Am3+ ion was not much affected (with a slight increase) over the entire range of diluent compositions in the case of LI, a gradual decline in the extraction of the Eu3+ ion suggested a reversal in the separation trend with Am3+ being preferentially extracted with a solution of LI in pure isodecanol. On the other hand, a sharp decline was seen for the extraction of both Am3+ and Eu3+ in the entire range of diluents containing various fractions of isodecanol when LII was used. The unusual extraction was attributed to the difference in the complexation behaviour of LI and LII, which was explained on the basis of photoluminescence (PL) spectroscopy as well as XAS studies. The PL studies suggested absence of any inner-sphere water molecules from the lifetime data, while the splitting of emisison peaks and asymmetry ratio values gave an idea about the complex geometry. On the other hand, the XAS studies gave information about the bonding in the coordination complexes.

Infectious bursal disease (IBD), caused by infectious bursal disease virus (IBDV), has recently been reported in chickens vaccinated with classical or intermediate types of vaccines from various regions of India due to the emergence of novel very virulent strains of infectious bursal disease virus (vvIBDV). In the present study, suspected samples of IBD were collected from poultry flocks of districts of Gujarat and Nagpur (Maharashtra), identified using PCR and grouped as per traditional and new genogrouping pattern. Out of 54 bursa samples, 21 (38.89%) yielded the expected amplicon of 743 bp (701–1444 bp), and were found positive for IBDV. Among these 21 positive flocks, 11 (52.38%) were already vaccinated. Upon nucleotide sequencing of amplicon and its deduction into amino acids, it was found that all the sequences of present study were related to vvIBDV according to old classification pattern. Considering the new genogrouping pattern, nine and four sequences of this study fell within G3a and G3b lineage, respectively. These sequences revealed important differences at key amino acid positions with respect to classical (G1 genogroup), variant (G2 genogroup) type of IBDV and classical vaccines. Further divergence from prototypic vvIBDV strains was revealed as, D-N at 212 position (N = 9) and 279 position (N = 1). In sequences from Maharashtra (group 2 of G3a lineage), occurrence of V instead of P/T/A at 222 position was recorded as a novel and conspicuous substitution in the immunodominant peak A of VP2 hypervariable region. Additional changes at 270 (3 sequences) and 272 positions (4 sequences) could be attributed to reverse mutation or recombination with vaccine strains. In conclusion, both point mutation and genetic reassortment with intermediate type of vaccines were found to be responsible for generation of novel vvIBDV strains in this area which belonged to G3a and G3b genogroups.

Two novel extraction chromatography resins (ECRs) containing two diglycolamide (DGA) -functionalized calix[4]arenes with n-propyl and isopentyl substituents at the amide nitrogen atom, termed as ECR-1 and ECR-2, respectively, were evaluated for the uptake of Th(IV) from nitric acid feed solutions. While both the resins were having a quite high Th(IV) uptake ability (Kd >3000 at 3 M HNO3), the uptake was relatively lower with the resin containing the isopentyl DGA, which appeared magnified at lower nitric acid concentrations. Kinetic modeling of the sorption data suggested fitting to the pseudo-second order model pointing to a chemical reaction during the uptake of the metal ion. Sorption isotherm studies were carried out showing a good fitting to the Langmuir and D-R isotherm models, suggesting the uptake conforming to monolayer sorption and a chemisorption model. Glass columns with a bed volume of ca. 2.5 mL containing ca. 0.5 g lots of the ECRs were used for studies to assess the possibility of actual applications of the ECRs. Breakthrough profiles obtained with feed containing 0.7 g/L Th(NO3)3 solution resulted in breakthrough volumes of 8 and 5 mL, respectively, for the ECR-1 and ECR-2 resins. Near quantitative elution of the loaded metal ion was possible using a solution of oxalic acid and nitric acid. A method for the separation of Th-234 from natural uranium was demonstrated for the possible application of ECR-1.

Background Malaria continues to be a major public health problem in the Northeastern part of India despite the implementation of vector control measures and changes in drug policies. To develop successful vaccines against malaria, it is important to assess the diversity of vaccine candidate antigens in field isolates. This study was done to assess the diversity of Plasmodium falciparum AMA-1 vaccine candidate antigen in a malaria-endemic region of Tripura in Northeast India and compare it with previously reported global isolates with a view to assess the feasibility of developing a universal vaccine based on this antigen. Methods Patients with fever and malaria-like illness were screened for malaria and P. falciparum positive cases were recruited for the current study. The diversity of PfAMA-1 vaccine candidate antigen was evaluated by nested PCR and RFLP. A selected number of samples were sequenced using the Sanger technique. Results Among 56 P. falciparum positive isolates, Pfama-1 was successfully amplified in 75% (n = 42) isolates. Allele frequencies of PfAMA-1 antigen were 16.6% (n = 7) for 3D7 allele and 33.3% (n = 14) in both K1 and HB3 alleles. DNA sequencing revealed 13 haplotypes in the Pfama-1 gene including three unique haplotypes not reported earlier. No unique amino-acid substitutions were found. Global analysis with 2761 sequences revealed 435 haplotypes with a very complex network composition and few clusters. Nucleotide diversity for Tripura (0.02582 ± 0.00160) showed concordance with South-East Asian isolates while recombination parameter (Rm = 8) was lower than previous reports from India. Population genetic structure showed moderate differentiation. Conclusions Besides documenting all previously reported allelic forms of the vaccine candidate PfAMA-1 antigen of P. falciparum, new haplotypes not reported earlier, were found in Tripura. Neutrality tests indicate that the Pfama-1 population in Tripura is under balancing selection. This is consistent with global patterns. However, the high haplotype diversity observed in the global Pfama-1 network analysis indicates that designing a universal vaccine based on this antigen may be difficult. This information adds to the existing database of genetic diversity of field isolates of P. falciparum and may be helpful in the development of more effective vaccines against the parasite.

Bulk matter produced in heavy ion collisions has multiple conserved quantum numbers like baryon number, strangeness and electric charge. The diffusion process of these charges can be described by a diffusion matrix describing the interdependence of diffusion of different charges. The diffusion coefficient matrix is estimated here from the Boltzmann kinetic theory for the hadronic phase within relaxation time approximation. In the derivation for the same, we impose the Landau-Lifshitz conditions of fit. This leads to e.g. the diagonal diffusion coefficients to be manifestly positive definite. The explicit calculations are performed within the ambit of hadron resonance gas model with and without excluded volume corrections. It is seen that the off-diagonal components can be significant to affect the charge diffusion in a fluid with multiple conserved charges. The excluded volume correction effects is seen to be not significant in the estimation of the elements of the diffusion matrix., 16 pages, 6 figures, Comments are very much welcome

The hydrodynamic performance of composite wavy submerged porous plate attached to a wall is investigated using numerical method multi-domain boundary element method in the linearized water wave theory in which wave past the porous barriers are modeled using Darcy’s law. Effect of the presence of wall on the hydrodynamic parameters like reflection coefficient, dimensionless wave height, wave force and moment acting on the composite wavy porous structure, and horizontal force on the vertical rigid wall is analyzed for various physical parameters like the number of ripple wavelength, structural porosity, submergence depth, and relative amplitude of composite wavy porous plate. The study demonstrates that the efficiency of hydrodynamic characteristics of the composite wavy porous plate attached to the wall is better compared to a horizontal porous plate attached to the wall of the same applicability conditions (around 27% reduction in wave reflection). Moreover, optimum performance of this kind of breakwater system is increased by considering the lower submergence, higher relative ripple amplitude, appropriate relative amplitude, and suitable moderate porosity of the structure in the range of wavenumber 1 < k0h < 5. Dimensionless wave height, horizontal load on the impermeable wall are reduced to zero, while substantial minimization of vertical load on the structure with suitable consideration of the other influencing parameters of porosity Gp = 0.3, relative amplitude Ds/h = 0.1, relative ripple wavelength m > 3, and submergence depth h1/h = 0.3. The present structural arrangement will be useful for attenuating wave effects on the sea wall.

Pesticides have played a serious role in achieving the utmost crop production but maximum usage and accumulation of pesticide residues is very detrimental to aquatic and other ecosystem. Pesticide residues in water have become a major challenge over the last few decades and has been monitored in public water supply resources in national capital territory. Results shows that continuous consumption of contaminated water can pose severe health threats to local parts of this area. Central Pollution Control Board (CPCB), Delhi, shows that ? and ? isomers of endosulphan residues within the Yamuna river. High concentration levels of ?-HCH (0.259 ?g/l) and malathion (2.618 ?g/l) were detected within the surface water samples collected from the river Ganga in Kanpur, Uttar Pradesh (UP). High concentration levels of methyl parathion, endosulfan, and DDT were observed in water samples collected from the river at Bhagalpur, Bihar. The Industrial Toxicology Research Centre (ITRC), Lucknow (UP) study shows the result 0.5671 ppb concentrations of endosulfan in the river at Allahabad, UP. Same results were found in other water samples in India.

Developed coastal regions are the hotspots for contaminated groundwater discharge, affecting sensitive marine ecosystems. The present study aims to identify submarine groundwater discharge (SGD) locations and quantify the contaminant load reaching to the western coast of India (Gujarat coast) using stable isotopes, seepage meter, heat and solute transport model. The coastal aquifers are highly enriched in trace metals due to various active natural processes and anthropogenic activities across the coast. Terrestrial and recirculated SGD was a significant contributor to flow and metal load, which ranged from 1.04 to 181.1 m3.year−1 and 0–77.41 kg.year-1, respectively. The highest estimated SGD in the Gujarat coast was relatively less than the SGD reported in the Bay of Bengal and comparable to the South Chennai coast. The order of metal flux found in the study was Zn > Fe > Cr > Pb > Ni > Cu > Mn, whereas the highest flux of Zn (77.41 kg. year−1) was reported at Fansa beach, which was 7x Fe-flux and 45 x Cr-flux, respectively. Higher micronutrients (Fe and Zn) load in the southern coast leads to increased vulnerability of eutrophication, algal blooms and biotic ligand formation in aquatic species. This enrichment of micronutrients in the coastal ecosystem was evident by the growth of seaweeds on the seabed at SGD identified locations.

The study aimed to explore the serum levels of HSP70 and identify its possible association with serum cortisol, thyroid hormones, and acute-phase protein concentrations in cattle naturally infected with foot-and-mouth disease (FMD) virus. After the FMD outbreak in an organized dairy cattle farm in India, blood samples were obtained from clinically infected (n = 40) and apparently healthy (n = 30) animals. Samples were processed and tested by an in-house DIVA assay for confirmation of FMD infection. Serum was analyzed for HSP70, cortisol, T4, T3, haptoglobin, and serum amyloid A by enzyme-linked immunosorbent assay (ELISA). HSP70 concentrations were significantly higher in the serum of clinically infected cattle (p 0.01) than the healthy group. To the best of our knowledge, this is the first report describing the elevated serum levels of HSP70 under infectious diseases of bovines. Cortisol (p 0.05), haptoglobin (p 0.001), and serum amyloid A (p 0.05) concentrations also markedly increased in the diseased animals; however, no differences (p 0.05) were found in T4 and T3 levels between healthy and infected cattle. Elevated HSP70 concentration correlated positively with high cortisol (p 0.05) and haptoglobin (p 0.001) levels suggesting an essential link between these acute events during clinical infectious phase of FMD.

We present a theoretical model of a four-photon excitation process to the Rydberg state in thermal atomic vapor where the motion-induced dephasing in the system is eliminated. This is achieved by arranging the four laser beams in a suitable geometry such that the residual wave vector is reduced to zero. The method of adiabatic elimination has been used to reduce the complex five-level system to an effective three-level system to study electromagnetically induced transparency (EIT) where the transition from ground state to second excited state can be considered as the effective probe and second excited state to the Rydberg state as the effective coupling transition. The effect of the blockade phenomenon is observed in the strong interaction regime, where the two atoms are considered to be moving with independent velocities and the system is Doppler averaged using Monte Carlo simulation technique. Also, the dephasing mechanisms in the system are investigated in detail. Though the system is not frozen during the excitation process, a strong blockade effect is still observed similar to the cold atom system. We conclude the paper with a proposal for experimentally investigating the four-photon excitation process to the Rydberg state in thermal rubidium vapor.

Pertraction of U(VI) from HNO3 feed into water through flat-sheet supported liquid membrane containing a series of monoamides, viz. N,N-dihexylhexanamide (DHHA), N,N-dihexyloctanamide (DHOA) and N,N-dihexyldecanamide (DHDA), as the carrier ligands were studied. The results obtained with monoamides were compared with those obtained with TBP, a contemporary ligand to monoamides. The permeation of U(VI) was primarily governed by the distribution ratio of U(VI) by the ligands. A mathematical equation was derived by solving the mass balance equation on the feed side and the receiver side of the membrane which fitted well to a series of experimental results in the present work.

In this paper, we report the impact of mechanical activation on structural, microstructural, thermal, and optical properties of Mg2TiO4 (MTO) nanoparticles prepared by high-energy ball milling. Williamson–Hall (W–H) method was carried out in order to understand the origin of the broadening in the X-ray diffraction (XRD) peaks and for the estimation of crystallite size of MTO nanocrystalline powder. It is revealed that the peak broadening is not only due to reduced coherently diffracting domain size but also due to a significant strain distribution. The calculated strain was 9.0 × 10−3 and the average crystallite sizes are 40–60 nm for 35-h milled powder and this result is consistent with transmission electron microscopy (TEM) analysis. To examine the nature of lattice fringes for the 35-h milled samples, high-resolution TEM study was carried out. It revealed that the as-prepared samples are highly crystalline in nature. The surface morphological studies were carried out by using scanning electron microscopy (SEM) and atomic force microscopy (AFM). Further, MTO nanoparticles showed a strong absorption at ~ 356 nm, and the bandgap values ranged between 3.26 and 3.78 eV with an increase of milling time from 0 to 35 h. The photoluminescence (PL) spectrum measured at room temperature showed the bands which are belong to the near band edge emission at 357 nm. The MTO nanoparticles prepared by mechanical alloying method exhibited promising optical properties which are suitable for commercial optoelectronic applications.

In the recent time, Submergence1 (Sub1)QTL, responsible for imparting tolerance to flash flooding, has been introduced in many rice cultivars, but resilience of the QTL to stagnant flooding (SF) is not known. The response of Sub1-introgression has been tested on physiology, molecular biology and yield of two popular rice cultivars (Swarna and Savitri) by comparison of the parental and Sub1-introgression lines (SwarnaSub1 and SavitriSub1) under SF. Compared to control condition SF reduced grain yield and tiller number and increased plant height and Sub1- introgression mostly matched these effects. SF increased ethylene production by over-expression of ACC-synthase and ACC-oxidase enzyme genes of panicle before anthesis in the parental lines. Expression of the genes changed with Sub1-introgression, where some enzyme isoform genes over-expressed after anthesis under SF. Activities of endosperm starch synthesizing enzymes SUS and AGPase declined concomitantly with rise ethylene production in the Sub1-introgressed lines resulting in low starch synthesis and accumulation of soluble carbohydrates in the developing spikelets. In conclusion, Sub1-introgression into the cultivars increased susceptibility to SF. Subjected to SF, the QTL promoted genesis of ethylene in the panicle at anthesis to the detriment of grain yield, while compromising with morphological features like tiller production and stem elongation.

Effective transportation of fly ash-water slurry through a pipeline from its generation site, a power plant, to a storage site by replacing commercial surfactants such as cetyl trimethyl ammonium bromide and sodium dodecyl sulfate by a natural dispersant extracted from Sapindus laurifolia was studied. The stability of fly ash slurry was determined from its rheological parameters, dispersant concentration, and stabilization mechanism. From surface tensiometric data, the critical micelle concentration of the dispersant was obtained to be 0.017 g/cc. The stabilization of high-concentration fly ash slurry has been studied through its rheological behavior by variation of temperature and dispersant and ash concentration. The rheological result obtained for fly ash concentrations in the range of 50-65% slurry was best justified by the Bingham plastic model. The wettability of fly ash particles is increased in the presence of dispersants, which is inferred from reduction of the surface tension value. The stabilization mechanism of the slurry is explained by a steric factor as indicated by the decrease in the zeta potential value. Air pollution is minimized at its destination site due to agglomeration of fly ash particles, which is confirmed from the SEM microphotograph.

Oxazines have brought much synthetic interest due to their extensive biological activities. These are the important category of heterocycles, which may be formally derived from benzene and its reduction products by convenient substitution of carbon (and hydrogen) atoms by nitrogen and oxygen. In the last few decades, oxazine derivatives have documented as worthy synthetic intermediates and also blessed with notable sedative, analgesic, anticonvulsant, antipyretic, antimicrobial, antitubercular, antimalarial, antioxidant, and anticancer activities. Nowadays, it is important to develop new classes of compounds with more effective mechanisms due to drug resistance activity in which the ability of drug to effectively treat disease can be reduced. The aim of the article is to collect and make a more generalized review on the synthesis of oxazine derivatives and their pharmaceutical and biological activities. We hope this review will provide ample references for the researchers concerned with azines in generally and oxazines in particular.

The rheological behavior of high ash Indian coal samples was investigated by blending fines (

Two multiple diglycolamide (DGA)-containing extractants where the DGA arms are tethered to the nitrogen atoms of two aza-crown ether scaffolds, a 9-membered aza-crown ether containing three ‘N’ atoms (LI) and a 12-membered aza-crown ether containing four ‘N’ atoms (LII), were evaluated for the extraction of the tetravalent actinide ions Np4+ and Pu4+. The tripodal ligand with three DGA arms (LI) was relatively inferior in its metal ion extraction properties as compared to the tetrapodal ligand with four DGA arms (LII) and Pu4+ ion was better extracted than Np4+ ion with both the ligands. A solvation extraction mechanism, where species of the type ML(NO3)4 are extracted, was found to be operative for both the ligands involving both the tetravalent actinide ions. While the extraction of the metal ions increased with the feed nitric acid concentration up to 4 M, a sharp decline in the extraction was seen after that. Quantitative extraction (>99%) of the actinide ions was observed with LII from 4 M HNO3, suggesting the possible application of the ligands for actinide partitioning of high-level waste. The structure and the composition of the complexes were optimized by DFT computations.

Monitoring of anti-malarial drug resistance is vital in Northeast India as this region shares its international border with Southeast Asia. Genetic diversity of Plasmodium parasites regulates transmission dynamics, disease severity and vaccine efficacy. P. falciparum chloroquine resistance transporter (Pfcrt), multidrug resistance-1 (Pfmdr-1) and kelch 13 propeller (PfK-13) genes which govern antimalarial drug resistance and three genetic diversity markers, merozoite surface protein 1 and 2 (Pfmsp-1, Pfmsp-2) and glutamate rich protein (Pfglurp) were evaluated from Tripura, Northeast India using molecular tools. In the Pfcrt gene, 87% isolates showed triple mutations at codons M74I, N75E and K76T. 12.5% isolates in Pfmdr-1 gene showed mutation at N86Y. No polymorphism in PfK-13 propeller was found. Polyclonal infections were observed in 53.85% isolates and more commonly in adults (p = 0.0494). In the Pfmsp-1 locus, the K1 allelic family was predominant (71.2%) followed by the 3D7/IC family (69.2%) in the Pfmsp-2 locus. RII region of Pfglurp exhibited nine alleles with expected heterozygosity of 0.85. The multiplicity of infection for Pfmsp-1, Pfmsp-2 and Pfglurp were 1.56, 1.31 and 1.06 respectively. Overall, the study demonstrated a high level of chloroquine resistance and extensive parasite diversity in the region, necessitating regular surveillance in this population group.

Two novel extraction chromatographic resins (EC), termed as RL-1 and RL-2, were prepared by impregnating two benzene-centered tripodal iglycolamide ligands (Bz-T-DGA) containing different spacer groups where the ligands are termed as L-1 and L-2, respectively. They were employed for the uptake of actinide and fission product ions, viz. Am3+, Eu3+, UO22+, Np4+, Pu4+, Sr2+, and Cs+, from acidic feeds. Weight distribution coefficient (Kd) values were measured by the batch method and the loaded metal ions were back extracted using a 0.01 M EDTA solution at pH 4. Kinetic modeling of the sorption data of Am(III) on both resins suggested pseudo-second order rate kinetics with rate constants of 1.68 × 10−6 and 2.47 × 10−6 g/cpm.min for the resins containing L-1 and L-2, respectively. Sorption isotherm studies indicated the Langmuir monolayer chemisorption phenomenon with Eu(III) experimentally determined saturation uptake capacities of 6.02 ± 0.11 and 5.49 ± 0.14 mg per g of RL-1 and RL-2 resins, respectively. As the batch uptake study results appeared encouraging, column studies were also carried out using both resins. The resin reusability data indicated a marginal change in the Kd values for the RL-1 resin up to three repeat runs beyond which a steady decrease of the Kd value was seen. On the other hand, in the case of RL-2 a steady decrease in the Kd values was observed for three repeat runs beyond which there was marginal change.

Solvent extraction studies were performed to understand the extraction behavior of Np4+ and NpO2 2+ from acidic feeds with CMPO (octyl (phenyl)-N,N-diisobutyl carbamoyl methyl phosphine oxide) diss...

The sorption of Eu(III) onto montmorillonite samples from different deposits such as those of Kutch (India), 10th Khutor deposit (Russia), and Cortijo de Archidona (Spain) was studied over a wide range of experimental conditions by varying the total Eu concentration, pH, and ionic strength. Various bentonite samples showed quantitative sorption at all pH values at low ionic strengths of the solution because of ion exchange interactions. At a higher ionic strength (1 M NaClO4), the sorption is pH-dependent because of the interaction with edge sorption sites and it differed from sample to sample. The difference in the mechanism of interaction at different ionic strengths was confirmed by time-resolved laser-induced fluorescence. Thermodynamic modeling was performed with all experimental data for montmorillonite samples from different sources to create a generalized model for describing their interaction with Eu(III).

A series of four N-pivot tripodal diglycolamide (DGA) ligands, where three DGA moieties are attached to the central N atom via spacers of different lengths and with varying alkyl substituents on the amidic nitrogen of DGA (LI-LIV), were studied for their extraction and complexation ability toward trivalent lanthanide/actinide ions, including solvent extraction, complexation using spectrophotometric titrations, and luminescence spectroscopic studies. Introduction of a methyl group on the amidic nitrogen atom gives rise to a 400 fold increase of the Eu distribution ( D) value [LIII (NMe) vs LII (NH)] at 1 M HNO3. Enlargement of the spacer length between the pivotal N atom and the DGA moieties with one carbon atom results in a 14 times higher DEu value [LI (C3) vs LII (C2)]. Slope analyses showed that Eu3+ was extracted as a bis-solvated species with all four ligands. The compositions of the Eu3+/L complexes were further confirmed by spectroscopic measurements, its formation constants following the order: LIII > LIV > LI > LII. Luminescence spectroscopy and electrospray ionization mass spectrometry revealed that all four ligands form [Eu(L)2(NO3)3] complexes. Density functional theory and thermodynamic parameters corroborated the existence of [Eu(L)2(NO3)3] complexes.

The effects of poly(methyl methacrylate) PMMA removal procedures on the surface chemistry of both geological and synthetic MoS2 are investigated. X-ray photoelectron spectroscopy (XPS) is employed following acetone dissolution, thermal annealing, and ultraviolet-ozone (UV-O3) treatment of PMMA-coated MoS2 samples. Specifically, we focus on the efficacy of polymer residue removal procedures and oxidation resistance of the different samples. Acetone dissolution followed by ultra-high vacuum (UHV) annealing was highly effective in removing carbon residues from one type of geological sample however not for a synthetic sample produced by sulfurization. Similarly, different types of samples require varying lengths of UV-O3 exposure time for proper removal of residues, and some exhibit oxidation as a result. UV-O3 exposure followed by a UHV anneal resulted in successful removal of carbon residues from MoS2 produced by sulfurization while a substantial carbon signal remained on a chemical vapor deposited MoS2 sample subjected to the same process. Differences in the effects of removal procedures are attributed to differences in surface morphology and material quality. For device fabrication applications, this work highlights the importance of developing PMMA removal processes specific to the MoS2 used with full consideration for the processing required to obtain the MoS2.

Several commonly studied room temperature ionic liquids (RTILs) were studied for their radiolytic stability by exposing to gamma ray dose up to a maximum of 1000 kGy. The RTILs are Cnmim•X (where, n = 4, 6, and 8 and X = PF6 or NTf2) and were irradiated in a gamma ray chamber as such in stoppered glass tubes. Post irradiations, the RTILs appeared deeply colored and were characterized by FTIR and the hydrodynamic parameters such as density, viscosity, interfacial tension (IFT). The extraction properties of the RTILs were examined for water as well as nitric acid uptake and also for the extraction of U O 2 2 + ion, a representative actinide ion present in radioactive feeds, using TBP using the irradiated RTILs. The results obtained with the irradiated RTILs were compared with the pristine RTILs and discussion is made taking note of the existing literature.

Ureas and thioureas, otherwise known as carbamides and thiocarbamides, respectively, are rich sources of nitrogen. Urea has a wide range of applications in agriculture, the chemical industry, and a...

The extraction behaviour of U(VI), Th(IV) and Nd(III) was investigated as a function of nitric acid concentration for diamide based extractants, namely, N,N,N′,N′-tetraoctyl-3-carbonylpentanediamide (TOCPDA) and 4-carbonyl-heptanedioic acid bis-dioctylamide (CHADA). In addition, the distribution ratio was also measured for Pu(IV) and Sr(II) with 1.1 M CHADA in n-dodecane. These extractants were synthesized by adopting simple acid, amine coupling reaction with DCC (dicyclohexylcarbodiimide) and DMAP (N,N′-dimethylaminopyridine) as the coupling agent. The newly synthesized extractants were characterized by FT-IR, NMR, Mass, CHNS and HPLC. The extraction results indicated that CHADA shown has better extraction behavior for U(VI) compared to TOCPDA. In addition, CHADA coated HPLC column was examined for the retention behaviour of U(VI), Th(IV), and Nd(III). Computation studies based on density functional theory (DFT) were carried out to understand the complexing behaviour of U(VI), Pu(IV) and Sr(II) with CHADMA and TMCPDA.

The complexation of octyl-(phenyl)-N,N-diisobutyl carbamoyl methylene phosphine oxide (CMPO), a well-known ligand for actinide partitioning, with trivalent actinides and lanthanides was investigated in a room temperature ionic liquid, viz. 1-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide ([C4mim][Tf2N]). Solvent extraction studies in [C4mim][Tf2N] medium indicated the participation of three CMPO molecules in the extracted complex. Optical spectroscopic studies in [C4mim][Tf2N] confirmed that CMPO forms predominantly ML, ML2 and ML3 (where M = Nd3+, L = CMPO) types of complexes. The stability constants of the Nd3+/CMPO complexes were several orders of magnitude higher in [C4mim][Tf2N] than those observed in acetonitrile or methanol, which explains the higher extraction ability of CMPO for trivalent f-cations in [C4mim][Tf2N]. Luminescence spectroscopic investigations in [C4mim][Tf2N] also predicted the nature of the extracted species as ML3 (where, M = Eu3+, L = CMPO). DFT calculations indicated the formation of ML33+ as the most populated species, which was further confirmed by the EXAFS measurements.

Extraction of 137Cs from 1.6 L of diluted aqueous simulated high-level waste (SHLW) (at 1 M HNO3) was carried out using a two-stage centrifugal contactor system (bowl volume 200 mL) into 2 ...