Amyloid beta (Aβ) aggregation is generally associated with Alzheimer’s onset. We have demonstrated that incubation of dopaminergic SH-SY5Y cells with an Aβ peptide fragment (an 11-mer composed of residues 25–35; Aβ (25–35)) results in elevated intracellular nitrosative stress and induces chemical mutation of protein disulfide isomerase (PDI), an endoplasmic reticulum-resident oxidoreductase chaperone. Furthermore, Aβ (25–35) provokes aggregation of both the minor and major biomarkers of Parkinson’s disease, namely, synphilin-1 and α-synuclein, respectively. Importantly, fluorescence studies demonstrate that Aβ (25–35) triggers colocalization of these Parkinsonian biomarkers to form Lewy-body-like aggregates, a key and irreversible milestone in the neurometabolic cascade leading to Parkinson’s disease. In addition, fluorescence assays also reveal direct, aggregation-seeding interactions between Aβ (25–35), PDI and α-synuclein, suggesting neuronal pathogenesis occurs via prion-type cross-transfectivity. These data indicate that the introduction of an Alzheimer’s-associated biomarker in dopaminergic cells is proliferative, with the percolative effect exercised via dual, independent, Parkinson-pathogenic pathways, one stress-derived and the other prion-like. The results define a novel molecular roadmap for Parkinsonian transfectivity via an Alzheimeric burden and reveal the involvement of PDI in amyloid beta induced Parkinson’s. We have also explored the ability of phytochemicals to intercept Aβ-driven Parkinson’s pathogenesis via multiple mechanisms. Results from these studies will be discussed.. This work is partly presented at 8th Edition of International Conference on Chemistry Education and Research August 27-28, 2018
Chemistry textbooks for senior high school commonly used by chemistry teachers as well as students have been reviewed on the concepts of quantum numbers and electronic configurations. A number of six textbooks and thirty teachers from fifteen senior high schools were taken as samples. Typically common misconceptions were found on the authors as well as the teachers. For quantum number â�?�?=1, the ordering of mâ�?�?: -1, 0, +1 is wrongly associated with alphabetic ordering of p orbitals: px, py, pz, within five of the six textbooks; while the other one mistakenly stated that it is immpossible to know the relationship beween the two, and thus cartesian-axes labels are just arbitrarily. In accordance to Hund’s rule, five of the six books stated that the unpaired electrons are always to be (ms) of +½ (spin-up, ↑), while the rest stated that it might also be (ms) of -½ (↓). In writing electronic configurations of elements for all textbooks it is always governed with aufbau principle due to increasing (n+â�?�?) of Madelung. In the case of (3)d block, [Ar] 4s(1-2) 3d(1-10) electronic configurations were favored in all textbooks, though four of them stated that [Ar] 3d(1-10) 4s(1- 2) were also allowed. Thus, an odd statement appears that electronic configuration could be written in two ways. Three textbooks introduced the terms of the last and the nth electron to be associated with the corresponding quantum numbers, and this leads to serious further misconceptions. No statement was found that the ordering of (n+â�?�?) pattern is actually only true for the first twenty elements. Similar misconceptions were also observed for teachers. Only seven teachers stated that the unpaired electrons can be either (ms) +½ or (ms) -½, however, all teachers always take (ms) +½ as the correct answer. Nine teachers stated that the energy of 3d orbitals is lower than that of 4s, but the electronic configurations of transition elements were written as [Ar] 4s(1-2) 3d(1-10). Thus, eventhough some teachers seems to have different idea with the textbooks, they are inconsistent. It might be suggested that the chemistry textbooks must be revised to the correct concept by introducing the solution of Schrodinger equation and the correct order of energy of orbitals as observed by photoelectron spectroscopy. This work is partly presented at 8th Edition of International Conference on Chemistry Education and Research August 27-28, 2018
Oil palm is currently the world’s main vegetable oil crop due to its high productivity and long life span. However, the yearly harvest was significantly reduced, due to the basal stem rot (BSR) disease which is caused by a fungus, Ganoderma boninense. In 2010, the incidence of BSR disease was estimated to be about 3.7% with estimated affected areas of around 60,000 hectares. Losses due to Ganoderma disease is estimated to be about USD 0.5 billion. For the control of Ganoderma, integrated sanitation, biological and chemical controls were suggested. In the later, fungicides such as hexaconazole and dazomet were found effective to eradicate Ganoderma inoculum within infected stumps, therefore reducing the spread of Ganoderma. The chemical control can be further improved via nanotechnology platform through fungicide nanodelivery system (FUNADS), which is expected to prolonging the productive life of the infected palm, reducing the frequency of applying time by controlled release approach and to reduce the toxicity by enclosed it in biodegradable and toxic-free materials. In this work, two fungicides; hexaconazole and dazomet as the guests were encapsulated into nanomaterials as the hosts (chitosan and layered double hydroxides) for the formation of various FUNADSs using the host-guest supramolecular chemistry approach. The chemical structure of the synthesized nanofungicides was evaluated using x-ray diffraction (XRD), electron microscopy, dynamic light scattering (DLS), Fourier transform infrared spectroscopy (FTIR), and thermogravimetric (TGA/DTG) analyses. The DLS and high resolution transmission electron microscopy (HRTEM) show the FUNADs can be synthesised using various host and guest combinations, and can be turned into the nanoparticles by adjusting the synthesis parameters. In vitro fungicide release from the FUNADs shows a sustained release manner. Furthermore, in vitro anti-fungal studies of the FUNADs against G. boninense shows better inhibition and lower EC50 value compared to their counterparts, the bare fungicides. This work is partly presented at 8th Edition of International Conference on Chemistry Education and Research August 27-28, 2018
ALDHs (aldehyde dehydrogenases) are enzymes that help the body metabolise highly reactive aldehydes into carboxylic acids. ALDH deregulation has been linked to a variety of malignancies. They're useful as a cancer stem cell (CSC) marker because of the high activity found in CSCs, and high expression has been linked to chemotherapeutic drug resistance. Although the exact role of ALDH is unknown, new evidence suggests that many isoforms of the ALDH1 family, including ALDH3A1 and ALDH7A1, play important roles in a variety of cancers. We will present new data on small molecules that inhibit ALDH functional activity using cell free and cell-based assays to investigate the role of ALDH functional activity. Diethylbenzaldehyde (DEAB) was used as a control for inhibition, while the Aldefluor assay was used to demonstrate functional activity. In addition, our research in prostate cancer demonstrated that many ALDH-affinic probe compounds were effective to diminish cell survival in both drug-resistant PC3 prostate cancer cells and patient-derived samples, with a synergistic impact when combined with docetaxel. Our early drug discovery method, which includes drug design to target ALDH7A1, an enzyme connected to oxidative stress, lysine metabolism, and a variety of illnesses, including cancer, will be discussed at the symposium. The aldehyde dehydrogenase (ALDH) family is an intracellular enzyme superfamily that oxidises a wide range of physiologically and pathophysiologically important aldehydes to harmless carboxylic acidsALDH family members not only have cytoprotective biological roles by detoxifying aldehydes, but they also influence cell proliferation, differentiation, and survival. ALDHs are versatile enzymes that oxidise a wide variety of endogenous and exogenous aldehydes. In 31 percent of nonsmall cell lung tumours, we found genetic abnormalities in ALDH1A1, ALDH1A3, or ALDH3A1, 86 percent of which were gene amplification or mRNA upregulation, based on data from The Cancer Genome Atlas and Gene Expression Omnibus (NSCLCs). Chemoresistance was influenced by the expression of these isoenzymes, and patients' life periods were shortened. These enzymes, we thought, give an oxidative advantage for NSCLC persistence. To explore this notion, we used DIMATE, an irreversible ALDH1/3 inhibitor, in combination with genetic and pharmacological techniques. DIMATE showed cytotoxicity in 73 percent of NSCLC cell lines examined and antitumor activity in orthotopic xenografts via formation of hydroxynonenal-protein adducts, GSTO1-mediated glutathione depletion, and elevated H2O2. ALDH1/3 disruption caused cell death when combined with ROS-inducing drugs or glutathione production inhibitors, confirming this finding. Combination treatment with DIMATE produced robust synergistic effects with tumour regression in lung cancer xenografts with high to moderate cisplatin resistance. These findings suggest that NSCLCs with high levels of ALDH1A1, ALDH1A3, or ALDH3A1 could be treated with inhibitors of these isoenzymes as monotherapy or in conjunction with chemotherapy to overcome patient-specific treatment resistance.espond to the protein-level variations seen in normal vs. tumour tissue, with undetectable or low staining in normal pneumocytes moving to moderate or high staining in tumour tissues.
Role of polymers is substantial in delivering protein drugs. Delivery of proteins; however, is challenging due to complex interactions including hydrophobic interaction, electrostatic interaction, hydrogen bonding and interaction between adsorbed protein molecules which may lead to loss of protein stability. Several factors that affect these interactions include polymer type, surface charge, pH and ionic strength of the solvent system, presence of competing proteins. It is critical to attain mechanistic understanding of adsorption of proteins at solid/ liquid interfaces to deliver the protein in safe and effective form at the site of action. Use of different polymers intended for drug delivery and analytical techniques such as dynamic light scattering spectroscopy, fluorescence spectroscopy and circular dichroism spectroscopy is demonstrated to screen the factors for development of stable dosage form. Evaluation of the changes in secondary and tertiary structure of recombinant human growth hormone (r-hGH) upon adsorption at biodegradable Poly (lactideco- glycolide) PLGA nanoparticles of different hydrophobicity as a function of pH is illustrated to understand the nature of the interactions that govern the adsorption of the protein on the polymer, leading to successful design of sustained delivery systems. This work is partly presented at 8th Edition of International Conference on Chemistry Education and Research August 27-28, 2018
A silyl cation is well known to be one of the highly reactive Lewis acids, and is available for activation of unsaturated compounds. We developed a sila- Friedel–Crafts reaction, in which the addition of silyl cation to the aromatic moiety followed by deprotonation induces Si-C bond formation and applied it to synthesize various dibenzosiloles such as trisilasumanene and so on. We thought an intermediary silyl cation or its arene complex can add to multiple bonds to form -silyl cations, which undergo Friedel-Crafts reaction with an aromatic ring existed in a molecule to give the corresponding silacyclic compounds. We have investigated the reactions using dialkylbenzylhydrosilanes and dialkylhydro-1-naphthylsilanes as precursors of silyl cations, alkynes, alkenes, allenes, carbon dioxide, and aldehydes as multiply bonded compounds, trityl tetrakis(pentafluorophenyl)borate (TPFPB) as a hydride-abstracting reagent, and 2,6-di-tert-butyl-4-methylpyridine as a base. Interestingly, we have found that cyclization occurred only at the 8-position of the naphthalene ring in the reactions using dialkyl-1-naphthylsilanes and alkenes. We also studied on intramolecular version of the reactions using alkynes. Namely, we prepared aromatic compounds bearing trimethylsilyl- ethynyl and dialkylhydrosilyl groups at the neighboring position and treated them with a small amount of TPFPB to give the corresponding aromatic ring-fused siloles and disiloles via single and double intramolecular chain hydrosilylation reactions with silyl cations as chain carriers, respectively. In these reactions, -silyl cations are considered to have undergone hydride abstraction from the starting hydrosilanes instead of Friedel-Crafts reactions in the former reactions. In this presentation, we wish to report on the details of these reactions.
The chemistry of graphene is growing rapidly in last decade and broad range of graphene derivates was prepared. Nevertheless, only two stoichiometric derivates are currently known: hydrogenated and fluorinated graphene (graphane and fluorographene). Compared to graphene, these materials exhibit significantly different properties, e.g. higher reactivity as well as large differences in physical properties. Especially fluorographene can be applied as a substrate for nucleophilic substitution reactions, which significantly extend the possible chemical modifications of graphene. Currently, the chemistry of the other 2D materials starts to be explored. However, the chemistry of inorganic 2D materials like pnictogens and transition metal dichalcogenides is not well known and only several procedures were already reported. In comparison with graphene, new synthetic protocols have to be applied because the chemistry of these materials is extremely variable. In the case of transition metal dichalcogenides, the formation of the M-X-C bond (M is a metal, X is any chalcogenide) can be used as a starting point for exploring their chemistry and for further derivatisation. The chemistry of layered pnictogens is significantly different. In this case, various reactions including nucleophilic substitution can be applied, however, the bonding through the oxygen functionalities on pnictogen surface is observed in many cases
Due to its unique atom-thick 2D structure and remarkable physicochemical properties, graphene has been sparked a flurry of research into its optical, electronic, thermal, and mechanical properties. In particular, a great deal of recent attention has been attracted to explore graphene and graphene composites for photoelectrochemical applications. Recently, much works have been done on attempting to design and prepare novel graphene-based materials for a wide range of applications in photo-electrochemistry, ranging from photoelectrochemical solar cells, photocatalytic decomposition of organic pollutants, and H2 evolution. In this feature article, we summarize the state of research on graphene-based materials for photo-electrochemistry. The prospects and further developments in this exciting field of graphenebased materials are also discussed. Won-Chun Oh is a Professor in the Department of Advanced materials and engineering at Hanseo University in Korea and School of Materials Science and Engineering at Anhui University of Science and Technology in China. He obtained a Ph.D. degree at Dankook University in 1995. And, he is guest professor in some of Universities in China, Thailand and Indonesia. He obtained the ‘Research Front’ award, ‘Yangsong’ award, “Excellent Paper Award”, and the Best Paper Award” in 2011, 2012 and 2015, and Award of appreciation from ICMMA2011 and ICMMA2014. He is appointed as one of the “Conference Chairman and Local Chairman” from 2007 to present year. His current research fields are nanostructured materials such as metal/nanocomposite, graphene materials and metal nanoparticles, and their catalytic applications for future energy sources and green chemical technologies. He is the author or a coauthor of 693 papers published in domestic and international journals. He serves as the Editor-in- Chief of the Journal of Multifunctional Materials and Photoscience, Asian Journal of Materials Chemistry and the Advisory Board Member of the Asian Journal of Chemistry.
Colloidal suspensions are model systems to study phase transformations of first order as crystallization of a liquid system. The particles of colloidal suspensions are in size of several hundred nanometres and the carrier fluid is transparent in the spectrum of visual light. These characteristic features make colloidal suspensions easily accessible for optical investigations. The structural transformations are very sluggish and can be monitored in-situ. In the present work, light scattering experiments are performed to investigate homogeneous nucleation in the interior and heterogeneous nucleation on the container walls of silica colloidal suspensions and to measure the growth velocity of the crystal. Since nucleation processes require shortrange ordering as precursor of their formation, we conduct ultra-small-angle scattering of X-rays of synchrotron radiation at DESY Hamburg to determine the topological short-range order of monodisperse colloidal suspensions in liquid phase far away from thermodynamic equilibrium. In such a way, the entire pathway of crystallization from the stable liquid to the metastable liquid state, the formation of short-range ordering over crystal nucleation and eventually crystal growth is quantitatively investigated. The experimental results are analysed within current models of formation of aggregates of different structure, classical nucleation theory and the Wilson-Frenkel theory of crystal growth. From measurements of crystal growth and its analysis within the Wilson-Frenkel theory, the deviation from thermodynamic equilibrium of a shear melted crystal is inferred as defined by the difference of chemical potential between the metastable liquid and the stable solid. The in-situ investigations of homogeneous crystal nucleation are used to determine the solid-liquid interface which is very difficult to measure by other methods. The measurement of the growth of a planar liquid-solid interface allows for detailed information of the particle attachment kinetics of particles from the liquid to the crystal
A high grade TiO2 product of 99.1% purity has successfully been prepared from the Egyptian Rosetta titania slag by its proper roasting with sodium hydroxide. The reaction product was then successively washed by water followed by controlled HCl acid leaching procedures in order not to dissolve the titanium values. The first step has aimed to dissolve silica, alumina besides possible V and Cr as well as recovering the excess NaOH while the HCl acid leaching step was so applied to selectively dissolve the iron and other impurities. The studied optimum conditions of roasting involved a slag/NaOH ratio of 5/6 at a roasting temperature of 850°C for 0.5 h. After both leaching circuits the titanium product left behind was filtered and properly washed with distilled water before drying at 110°C and calcination at 850°C.
Natural waters, especially in the Tahoua region, which are very salty, have a very high concentration of iron. They are the site of a significant precipitation of Fe(OH)3 in the water supply pipes. Ferrhydrite is formed in Dan Daji Illela's waters at 30°C. In order to understand the behavior of natural waters, we studied the influence of ions frequently encountered in them (Ca2+, Mg2+, Cl-, Na+, and SO42-) on the precipitation of iron in a bicarbonate medium. This study will allow us to determine if the addition of a particular ion can modify the behavior of water. Thus we studied the influence of Na+, Cl-, Mg2+, Ca2+ and SO42- ions at 30°C on the polymorphic transformations of Fe(OH)3. The experiments were performed in the bicarbonate medium with a concentration of 488 mg/L, in the presence of 5 mg/L of iron, at pHi (initial pH at the beginning of the experiment) and at room temperature for a precipitation time of 60 min. The Na+ and Cl- ions have no effect on the precipitation of Fe(OH)3 and promote the formation of the three varieties : ferrihydrite, lepidocrocite and goethite. Ca2+, Mg2+ and SO42- ions inhibit the formation of Fe(OH)3. The SO42- ions are directed towards the formation of the three varieties with the predominance of lepidocrocite. Ca2+ ions direct towards the formation of the three varieties with the predominance of goethite. The Mg2+ ions orient towards the formation of the three varieties with the predominance of ferrihydrite.
Different perennial grasses are one of the biomass options for lignocellulosic bioethanol production. The benefits of cultivating this form of biomass in terms of natural diversity and landscape protection are numerous. The NED pretreatment was combined with a traditional three-step bioethanol manufacturing procedure. The results demonstrate that glucose concentrations and hydrolysis efficiencies were similar at all pretreatment temperatures, ranging from 4.3 to 5.1 g/l and 15.2 percent to 17th.7%, respectively. On the other hand, as the pretreatment temperature climbed, the ethanol production fell. However, utilising this type of feedstock, the mass balance found that 100 g of biomass could create 3.3-4th.0 g ethanol. Because of the pretreatment, which may not have been adequate for soft biomass, the total efficiency and yield of the process were lower than predicted. Perennial grasses give interesting choices in the current demand for renewable and sustainable energy sources to alleviate the load of the global energy crisis. The ligno-cellulosic perennial grass Panicum virgatum (Switchgrass), which is used as a cheaper and more efficient feedstock for bioethanol production in Europe and the United States, might also be used in India for the same reason. The current study focuses on bioethanol production using P. virgatum (for the first time in India) and P. maxima. Switch grass seeds were received from the University of Bologna in Italy, whereas guinea grass seeds were obtained from the IGFRI in Jhansi, Uttar Pradesh, India. Both grasses were grown at IIT Delhi's Micromodel (an experimental field location). The harvested grass biomass was analyzed for various parameters including reducing sugars for subsequent bioethanol production. Among different pretreatment methods (Acid pretreatment, Alkali pretreatment and Microwave pretreatment) tested , alkali method showed maximum reducing sugars (280 mg/g for P. virgatum and 262 mg/g for P. maximum ) with 15 % reduction in crystallinity of cellulose in P. virgatum and 12% in P. maximum. RSM and CCD were used to improve it even further. To increase reducing sugar content, the impacts of four independent variables were investigated: NaOH (1-5%), temperature (60-100 C), substrate loading (1-3%), and reaction time (30-150 min). The following were the combined best conditions for maximum reducing sugar (68.3 percent): 2.5 percent substrate, 5% NaOH, and a reaction duration of 120 minutes at 100 degrees Celsius. A second order polynomial equation was used to evaluate the results (ANOVA). demonstrated a considerable increase in lowering sugars of 62-68 percent. The potential ethanol production from switch grass was calculated to be 26.72 percent, while it was 25.24 percent for P. maxima. This study shows that sugar yield is greatly increased under optimum pretreatment conditions, indicating that both P. virgatum and P. maximum grasses could be used as feedstock for bioethanol production in India. At the conference, all data related to all stages of cultivation, characterisation, pretreatment and hydrolysis procedures, and bioethanol production from these grasses will be discussed. Recent Publications 1. Adak, A., Tiwari, R., Singh, S., Sharma, S., & Nain, L. (2016) Laccase Production by a Novel White-Rot Fungus, Pseudolagarobasidium acaciicola LA 1 Through Solid-State Fermentation of Parthenium Biomass and Its Application in Dyes Decolorization. Waste and Biomass Valorization, 7, 1427-1435. 2. Arora, K., Sharma, S., & Monti, A. (2016) Bio- remediation of Pb and Cd polluted soils by switchgrass: A case study in India. International Journal of Phytoremediation, 7(18), 704-709. 3. Arora, K.; Kumar, A., & Sharma, S. (2012) Energy from Waste: Present Scenario, Challenges and Future Prospects towards Sustainable Development. IGI Global, 271-296. 4. Tiwari, G., Shivangi, Sharma, S., & Prasad, R. (2015) Bioethanol production: Future prospects from non-traditional sources in India. International Journal of Research in Biosciences, 4, 1-15. 5. Kumar, A., & Sharma, S. (2011) Non-edible oil seeds as biodiesel feedstock for meeting energy demands in India, Renewable and Sustainable Energy Reviews, 15, 1791-1800
New metal complexes derived from the interaction of tricine with some metal salts (Cu2+ and Co2+) were synthesized and characterized by spectral (IR, UV-vis.), magnetic, conductance and thermal analyses (TGA) measurements. The results suggest that L coordinate in bidentate manners via the COO and NH groups. Spectral and magnetic studies suggest an octahedral geometry around the investigated metal ions. Material studio program has been used for calculating HUMO, LUMO and DFT parameters on the atoms to confirm the geometry of complexes.
Background: The four-component system CaSO4EÂÂCaCO3EÂÂCaF2EÂÂH2O is a subsystem of more complex six-component system Na, Ca SO4,CO3,HCO3,FEÂÂH2O whose state of phase equilibria determines the conditions for utilization of liquid wastes of aluminum production. Aim: To investigate the solubility in the quaternary CaSO4EÂÂCaCO3EÂÂCaF2EÂÂH2O system and construction of its solubility diagram at 50ÂoC. Methods: In the present work, the results of studying the quaternary CaSO4-CaCO3-CaF2-H2O system at 50°C using the solubility method, with the purpose of determining the concentration parameters at the position of its geometrical figures (fields, curves, points) and also establishing the ratio of crystallization fields of individual equilibrium solid phases are considered. Results: Due to the low solubility of salts under these conditions, which is accompanied by a shift of the position of the figurative points to the water angle, the concentration of water is in the ratio 1: 5.
There has been great concern about the health risks associated with exposure to radioactivity present in soil, thus In this present study, absorbed dose rate measurements were carried out at some selected samples of contaminated soil . The purpose is to examine to what extent such measurements can be used to delineate the effect radiation to the workers and to assess the radiation risk of radioactive waste management personnel by calculating the annual dose of external radiation exposure and the amount of radioactive dose absorbed by the workers. Ladlum detector used to measure the exposure dose rate (AµR/h). The germanium system was used to analyze the samples collected from the decontamination processes, the activity concentration ranged from (1026.21 to 25961.5 ) Bq/kg. The value of the annual dos rate vary between (5.55E-05 to .40E-03 ) Sv/h
In this research, Cu/SiC/graphite nanocomposite coatings were fabricated by using pulse current (PC) electrodeposition method in the sulfate bath. The effects of PC parameters, like frequency, duty cycle, current density, and graphite concentration in the electrolyte bath, on the codeposition of graphite microparticles in the coating were analyzed. Also, the Cu-based composite coatings were tested by means of scanning electron microscopy (SEM) equipped with energy dispersive X-ray (EDX) spectroscopy, Vickers microhardness, and X-ray diffraction (XRD) techniques. Finally, the corrosion behavior of coatings in 3.5 wt.% NaCl solution were evaluated by using potentiodynamic polarization technique. The maximum code position of graphite was achieved at the current density of 12 A/dm2 , frequency of 15 Hz, duty cycle of 7%, and graphite content of 60 gr/l. Increasing graphite microparticles and decreasing SiC nanoparticles in the Cu-based composite coatings led to a decrease and increase in SiC content of the deposition, microhardness, friction coefficient, corrosion, and wear resistance, respectively. Furthermore, by embedding desirable SiC and graphite particles, Cu-based coating on the Cu substrate obtained both great wear and corrosion resistance.
Adsorption potential of natural bentonite clay (NBC) was investigated for wastewater defluoridation using batch adsorption experiments. Mineralogical and physicochemical characterization of the adsorbent was carried out by X-Ray Diffraction (XRD), XRay Fluorescence (XRF), Energy Dispersive X-Ray attached to Scanning Electron Microscopy (SEM-EDX), BET Specific Surface Area (SSAN2BET) analysis and Fourier-Transform Infrared Spectrometry (FTIR). The effect of various operational parameters such as contact time, initial fluoride concentration, adsorbent dose and initial pH solution were evaluated in batch procedures at room temperature (25 ± 2°C). The results of the batch adsorption experiments proved that 30 min of contact time was sufficient for attaining equilibrium. The maximum wastewater defluoridation (52.2%) was obtained in the acidic conditions (pH=2) and for 5 mg L -1 and 2 g L-1 of initial fluoride concentration and adsorbent dose, respectively. Kinetic studies revealed that fluoride adsorption fitted well to pseudo-second-order. The adsorption isotherm of fluoride sorption on NBC indicated that the maximum adsorption capacity was noted to be 4.4 mg g-1 . Batch adsorption data was better described by Freundlich confirming multilayer adsorption with heterogeneous energetic distribution of active sites and with interaction between adsorbed molecules. The originality of this paper consisted in introducing the mechanisms that might occur in the fluoride adsorption process. SEM-EDX and FTIR characterization techniques were found to be useful for achieving this purpose. The obtained results indicated that the ion exchange was probably the main process involved in the fluoride adsorption, accompanied by interactions of fluoride with metal ions forming Metal–F complexes
Bisphosphonates (Bps; have P-C-P moieties) are drugs that slow down or prevent bone loss. They inhibit osteoclasts, responsible for bone resorption, and allow osteoblasts, bone building cells, to be more effective; i.e., improve bone mass. Moreover, Bps are considered as anticancer drugs that cause bone damage. New complexes of etidronate disodium (Na2Etd) with Pd (II) and Pt (II) were synthesized and characterized based on elemental analysis, molar conductivity, thermal and spectral (IR, NMR, UV-visible, mass) measurements. Their anticancer activity was tested against human prostate (DU 145) and breast (MDA-MB231) cancer cell lines compared to Cisplatin, the market drug.
Intermolecular interactions of different configurations in the HClO3···CO and HOClO3···H2O dyads, as well as CO···HClO3···H2O triad systems have been studied at MP2/6-311++G(2d,2p) computational level. Molecular geometries, binding energies, cooperative energies, many-body interaction energies and energy decomposition analysis (EDA) were evaluated. The results reveal that the stability of cyclic triads are more than linear and in the order IV > III > II > I configurations. All of the triads have diminutive energy. Red shifts of H-O stretching frequencies for complexes involving HOClO4 as H-donor are predicted. The electronic properties of the complexes are analyzed using parameters derived from the quantum theory of atoms in molecules (QTAIM) methodology.
Separation of ytrrium and dysprosium from the prepared chloride liquor of HREEs concentrate (44.1% Y, 9.04% Dy, 5.15% Er, 4.56% Gd, 2.31% Yb, 1.33% Ho, and 1.23% Sm) has been studied. The concentrate was obtained by the sulfatizing roasting of xenotime bearing ferruginous sandstone (from southwestern Sinai) followed by precipitation as oxalates then dissolution in HCl. Treatment of the prepared REEs chloride with Na2CO3 was achieved under suitable conditions by the addition of H2O2 to the carbonate solution where Dy, Gd, Sm, and Yb are precipitated while Y & Er left behind in the filtrate. Extraction of 87.3% Dy from the produced precipitate was studied using Cyanex 272. The relevant conditions for extraction and stripping processes have been optimized. After acidification, Y in the filtrate and Dy in the stripping solution are precipitated as oxalates. Pure products of Y2O3 and Dy2O3 have been prepared and subjected to different analyses.
