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Platinum group metal (PGMs) are the most extracted non-renewable mineral resources in South African due to their high demand for various applications. During mineral processing some of these valuable metals are lost into the generated toxic which is excessively released into the environment. Adsorption technology offers advantages of ease operation, high effectiveness and opportunity to incorporate other techniques such as ion-imprinting method. Metal-organic frameworks have been explored as adsorbent due to their interesting properties such tuneable surface functionality and ability to host guest molecules. In this work, metal organic framework, MIL-101(Cr), (MIL= Matérial Institut Lavoisier) prepared from polyethylene-terephlalate waste was initially functionalised with ethylenediamine (ED) to form MIL-101(Cr)/ED for the adsorption of palladium (Pd) ions from aqueous solution. The successful incorporation of ED was confirmed by Fourier transform infrared spectroscopy with N-H vibrations at 3300 -3000 cm-1. The MIL-101(Cr)/ED achieved a maximum adsorption capacity (qm) of 454.2 mg/g for the uptake of Pd(II) ions in a pH =3.0 and 0.03 g of the adsorbent dose. MIL-101(Cr)/ED adsorbent was selective and fast towards the adsorption of Pd(II) ions. However, the regeneration and reusability of the adsorbent was still a challenge. The MIL-101(Cr)/ED was further grafting with glutaraldehyde (GA) to enhance the regeneration and reusability. This functionalisation was noted by the appearance 1554 and 1052 cm-1 for N-H bend and C-N stretch in the MIL-101(Cr)/ED-GA due to the amide bond formation. The efficiency of MIL-101(Cr)/ED-GA was tested for Pd(II) and platinum (Pt(IV)) ions. The data showed a good fit to the Langmuir isotherm and pseudo-second order (PSO) kinetic models. The estimated qm values were 414.4 for Pt(IV) and 308.3 mg/g for Pd(II) ions. The adsorption rate of the MIL-101(Cr)/ED-GA adsorbent was very rapid towards Pd(II) ions intake than Pt(IV) ions and result, NRF Thuthuka Research Grant

Shape memory alloys (SMAs)—a type of smart materials— offer unique benefits for constructing unique medical implants, especially for heart stents, vertebral nails, and braces. One of the widespread SMAs is nitinol (NiTi) which exhibits extraordinary shape memory ability to recover its initial form. However, due to the result of nickel (Ni2+) ions release, long-term usage of NiTi alloys would pose allergic and carcinogenic risks in orthopedics and clinical applications. To tackle these hurdles, we here demonstrate a surface modification technique via plasma polymerization in order to minimize Ni2+ ions release. NiTi substrates were initially exploited by plasma polymerization of ethylenediamine (EDA) with varying power values (25–50–75-100 W) and time rates (5–10-15 min) in order to assess the most efficient parameters for minimal toxic metal release. The samples were then tested for 14 days in a biomimicked media. As a result, 75 W-10 min plasma polymerized sample reduced Ni2+ ions release by 57.18 % compared to the base specimen. These results offer a significant outcome in deploying NiTi alloys into the biomedical field more safely through surface modifications using the plasma polymerization technique. © 2024 Elsevier B.V., Türkiye Bilimsel ve Teknolojik Araştırma Kurumu, TÜBİTAK: 118C254, 1919B011902136, 2209A

Shape memory alloys (SMAs)—a type of smart materials— offer unique benefits for constructing unique medical implants, especially for heart stents, vertebral nails, and braces. One of the widespread SMAs is nitinol (NiTi) which exhibits extraordinary shape memory ability to recover its initial form. However, due to the result of nickel (Ni2+) ions release, long-term usage of NiTi alloys would pose allergic and carcinogenic risks in orthopedics and clinical applications. To tackle these hurdles, we here demonstrate a surface modification technique via plasma polymerization in order to minimize Ni2+ ions release. NiTi substrates were initially exploited by plasma polymerization of ethylenediamine (EDA) with varying power values (25–50–75-100 W) and time rates (5–10-15 min) in order to assess the most efficient parameters for minimal toxic metal release. The samples were then tested for 14 days in a biomimicked media. As a result, 75 W-10 min plasma polymerized sample reduced Ni2+ ions release by 57.18 % compared to the base specimen. These results offer a significant outcome in deploying NiTi alloys into the biomedical field more safely through surface modifications using the plasma polymerization technique. © 2024 Elsevier B.V., Türkiye Bilimsel ve Teknolojik Araştırma Kurumu, TÜBİTAK: 118C254, 1919B011902136, 2209A

This paper describes a modification process of QTFs’ prongs with stable amine containing bilayer plasma polymer film and an application of quartz tuning fork (QTF) as a transducer for biomedical application. To produce stable amine containing film, first, we created plasma polymer films from hexane precursors. We then subjected those films to a second capping layer of ethylenediamine plasma polymer. The film was characterized by contact angle measurement, atomic force microscopy, and X-ray photoelectron spectroscopy. The effect of the interfacial structure onto stability was also analyzed in air. A model protein, BSA, sensing experiments were examined by measuring the shift in the resonance frequency of QTFs. The performance of the proposed sensor was investigated in terms of quality factor. These findings reveal that amine containing bilayer coated QTFs have the potential to be used in mass sensitive biosensor applications for future.

This paper describes a modification process of QTFs’ prongs with stable amine containing bilayer plasma polymer film and an application of quartz tuning fork (QTF) as a transducer for biomedical application. To produce stable amine containing film, first, we created plasma polymer films from hexane precursors. We then subjected those films to a second capping layer of ethylenediamine plasma polymer. The film was characterized by contact angle measurement, atomic force microscopy, and X-ray photoelectron spectroscopy. The effect of the interfacial structure onto stability was also analyzed in air. A model protein, BSA, sensing experiments were examined by measuring the shift in the resonance frequency of QTFs. The performance of the proposed sensor was investigated in terms of quality factor. These findings reveal that amine containing bilayer coated QTFs have the potential to be used in mass sensitive biosensor applications for future.

In this study, we employed an efficient and straightforward synthesis method for the functionalization and stitching of graphene oxide (GO) sheets with ethylenediamine (EDA). 3-D-structured GO-EDA was prepared by low reduction of the oxygen-containing functional groups of GO. The EDA was used as a nitrogen source to create the nitrogen-doped graphene (N-graphene), as well as a factor to control the self-assembly of graphene nanosheets into 3-D structures. The morphology, composition, and covalently grafted functional groups of GO-EDA were investigated by FT-IR and Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), Scanning electron microscopy (SEM), Transmission electron microscopy (TEM), and various electrochemical techniques. GO-EDA exhibits a layered structure resembling graphite, with an enhanced d-spacing of 0.373 nm compared with graphite (0.348 nm). The results showed that the porous channels of the synthesized GO-EDA facilitate the efficient transportation of lithium ions through the electrolyte-filled channels. The first discharge and charge showed specific capacities of 830.34 mAh g(-1) and 664 mAh g(-1), respectively at the current density of 100 mA g(-1), corresponding to an initial coulombic efficiency of ca. similar to 80%; superior to the GO reference (27.8%). Moreover, GO-EDA displayed improve cycling stability (maintaining a reversible capacity of similar to 300 mAh g(-1) at 200 mA g(-1) after 100 cycles). The improved electrochemical operation was ascribed to enhanced ion (Li+) transport within the graphitic layers by the increased d-spacing due to the inserted functional groups.

Graphene Quantum Dots (GQDs) were produced using electrochemical oxidation of graphite rods. Obtained GQDs were gamma-irradiated in the presence of the N atoms source, ethylenediamine. Both structural and morphological changes were investigated using UV-Vis, X-ray photoelectron and photoluminescence (PL) spectroscopy as well as atomic force microscopy. The ability of both types of dots to change PL intensity in the presence of pesticides such as malathion and glyphosate, as well as copper (II) ions was detected. These preliminary results indicated a high potential of produced GQDs to be applied as non-enzymatic PL sensors for the detection of selected pesticides and metal ions.

Graphene Quantum Dots (GQDs) were produced using electrochemical oxidation of graphite rods. Obtained GQDs were gamma-irradiated in the presence of the N atoms source, ethylenediamine. Both structural and morphological changes were investigated using UV-Vis, X-ray photoelectron and photoluminescence (PL) spectroscopy as well as atomic force microscopy. The ability of both types of dots to change PL intensity in the presence of pesticides such as malathion and glyphosate, as well as copper (II) ions was detected. These preliminary results indicated a high potential of produced GQDs to be applied as non-enzymatic PL sensors for the detection of selected pesticides and metal ions.

The paper is devoted to kinetic methods of chemical bath deposition of zinc sulfide ZnS from aqueous alkaline solutions containing ehylenediamine complex zinc salt Zn(En)n 2+ and diamide of thiocarbonic acid N2H4CS. It is established that the rate of formation of ZnS is weakly dependent on pH, depends on the concentration of the precipitant ((N2H4CS) and decreases with increasing concentration of ligand (ethylenediamine). The calculation of the theoretical curves on the experimentally obtained kinetic equation shows a satisfactory description of experimental data that allows to recommend it to calculate the rate of formation of ZnS in aqueous alkaline solutions of N2H4CS., Работа посвящена исследованию кинетическими методами химического осаждения сульфида цинка ZnS из водных щелочных растворов, содержащих этилендиаминовую комплексную соль цинка Zn(En)n 2+ и диамид тиоугольной кислоты N2H4CS. Установлено, что скорость образования ZnS слабо зависит от величины рН, зависит от концентрации осадителя (N2H4CS) и уменьшается с увеличением концентрации лиганда (этилендиамина). Расчет теоретических кривых по полученному экспериментально кинетическому уравнению показывает удовлетворительное описание полученных экспериментальных данных, что позволяет рекомендовать его для расчета скорости образования ZnS в водных щелочных растворах N2H4CS.

Pretreatment of miscanthus is essential for efficient enzymatic production of cellulosic ethanol. This study reports a possible pretreatment method for miscanthus using aqueous ethylenediamine (EDA) for 30 min at 180 °C with or without ammonia. The mass ratio of miscanthus to EDA was varied from 1:3, 1:1, and 1:0.5, keeping the mass ratio of miscanthus to liquid (EDA + Water) constant at 1:8. The ammonia-to-miscanthus ratio was 1:0.25. After pretreatment with a ratio of 1:3 miscanthus to EDA, about 75 % of the lignin was removed from the raw miscanthus with 90 % retention of cellulose and 50 % of hemicellulose in the recovered solid. Enzymatic hydrolysis of the recovered solid miscanthus gave 63 % glucose and 62 % xylose conversion after 72 h. EDA provides an effective pretreatment for miscanthus, achieving good delignification and enhanced sugar yield by enzyme hydrolysis. Results using aqueous EDA with or without ammonia are much better than those using hot water and compare favorably with those using aqueous ammonia. The delignification efficiency of EDA pretreatment is high compared to that for hot-water pretreatment and is nearly as efficient as that obtained for aqueous-ammonia pretreatment.

Pretreatment of miscanthus is essential for efficient enzymatic production of cellulosic ethanol. This study reports a possible pretreatment method for miscanthus using aqueous ethylenediamine (EDA) for 30 min at 180 °C with or without ammonia. The mass ratio of miscanthus to EDA was varied from 1:3, 1:1, and 1:0.5, keeping the mass ratio of miscanthus to liquid (EDA + Water) constant at 1:8. The ammonia-to-miscanthus ratio was 1:0.25. After pretreatment with a ratio of 1:3 miscanthus to EDA, about 75 % of the lignin was removed from the raw miscanthus with 90 % retention of cellulose and 50 % of hemicellulose in the recovered solid. Enzymatic hydrolysis of the recovered solid miscanthus gave 63 % glucose and 62 % xylose conversion after 72 h. EDA provides an effective pretreatment for miscanthus, achieving good delignification and enhanced sugar yield by enzyme hydrolysis. Results using aqueous EDA with or without ammonia are much better than those using hot water and compare favorably with those using aqueous ammonia. The delignification efficiency of EDA pretreatment is high compared to that for hot-water pretreatment and is nearly as efficient as that obtained for aqueous-ammonia pretreatment.

The development of novel strategies to prevent HIV-1 infection is of outstanding relevance. Metal complexes of Cu2+, Ni2+, Co2+ and Zn2+ derived from sulfonated and carboxylated poly(propylene imine) dendrimers with ethylenediamine core were evaluated as tunable antiviral agents against HIV-1. After demonstrating their biocompatibility, specific trends in the antiviral properties were found, related to both the dendritic scaffold (peripheral group, generation) and the bound metal ions (sort, amount). In HEC-1A and VK-2 cell lines, as model of the first barrier against HIV-1 infection, a high preventive inhibitory action was found, which also avoided virus internalization inside cells and inhibited both CCR5 and CXCR4 HIV-1 strains. In peripheral blood mononuclear cells (PBMC), as model of the second barrier, a dual preventive and therapeutic behavior was observed. A rational design of such metallodendrimers opens new avenues for the production of versatile and efficient treatments against HIV-1 infection., QC 20151204

Fullerenes-extracted soot, the by-product of fullerene synthesis, is a carbon composite. The application of this material for water treatment has not yet been developed. Herein, fullerenes-extracted soot in the form of powder containing amino groups was prepared by reacting the soot with ethylenediamine, and was used as an adsorbent of hexavalent chromium [Cr(VI)] for removing Cr(VI) from aqueous solutions; this removal was studied by batch adsorption experiments. The effect of experimental parameters such as the pH, initial Cr(VI) concentration, and agitation time on the adsorption process was investigated. The adsorption of Cr(VI) was highly pH-dependent and the optimal pH for the adsorption process was 3.0. The data of Cr(VI) adsorption by fullerenes-extracted soot modified with ethylenediamine (FES-ED) fit the Langmuir isotherm equation well. The maximum Cr(VI)-uptake capacity of FES-ED was 93 mg g−1. The desorption of Cr(VI) from the adsorbent was also studied. The adsorbed Cr(VI) was eluted with 20 mL of an aqueous solution with pH 12 and the percentage recovery of Cr(VI) was determined as 75%. The adsorption and desorption test using the same FES-ED powder was repeated in triplicate to examine the reusability of the adsorbent. The adsorption was 97% and the desorption was >70% through the adsorption–desorption cycles. The adsorption of methyl orange onto the FES-ED was also examined. The dye was almost quantitatively removed from the aqueous solution by the adsorbent (the initial concentration of methyl orange: 40 μg mL−1; the adsorbent added: 10 mg/40 mL). Thus, we concluded that the FES-ED can be used as a novel adsorbent for removing pollutants from water.

The synthesis of two new organic compounds, diisobutyl- and diisopentyl (S,S)-alpha(1),alpha(3)-bis(cyclohexylmethyl-1,3-imidazolidinediacetate is reported herein. The one-pot procedure was realized by the addition of the reducing agent and carbonyl compound into a methanolic solution of the parent compounds (isobutyl and isopentyl esters of (S,S)-alpha,alpha '-(1,2-ethanediyldiimino)bis[cyclohexanepropanoic acid] in appropriate stoichiometric ratios. The compounds were fully characterized by infrared, ESI-MS, 1D (H-1 and C-13) and 2D (COSY, HSQC and HMBC) NMR spectroscopy and elemental analysis. The spectral data confirmed the presence of the -CH2- group introduced between the nitrogen atoms of the ethylenediamine moiety, revealing a neutral form of the potential bidentate ligand.

The synthesis of two new organic compounds, diisobutyl- and diisopentyl (S,S)-alpha(1),alpha(3)-bis(cyclohexylmethyl-1,3-imidazolidinediacetate is reported herein. The one-pot procedure was realized by the addition of the reducing agent and carbonyl compound into a methanolic solution of the parent compounds (isobutyl and isopentyl esters of (S,S)-alpha,alpha '-(1,2-ethanediyldiimino)bis[cyclohexanepropanoic acid] in appropriate stoichiometric ratios. The compounds were fully characterized by infrared, ESI-MS, 1D (H-1 and C-13) and 2D (COSY, HSQC and HMBC) NMR spectroscopy and elemental analysis. The spectral data confirmed the presence of the -CH2- group introduced between the nitrogen atoms of the ethylenediamine moiety, revealing a neutral form of the potential bidentate ligand.

The synthesis of two new organic compounds, diisobutyl- and diisopentyl (S,S)-alpha(1),alpha(3)-bis(cyclohexylmethyl-1,3-imidazolidinediacetate is reported herein. The one-pot procedure was realized by the addition of the reducing agent and carbonyl compound into a methanolic solution of the parent compounds (isobutyl and isopentyl esters of (S,S)-alpha,alpha '-(1,2-ethanediyldiimino)bis[cyclohexanepropanoic acid] in appropriate stoichiometric ratios. The compounds were fully characterized by infrared, ESI-MS, 1D (H-1 and C-13) and 2D (COSY, HSQC and HMBC) NMR spectroscopy and elemental analysis. The spectral data confirmed the presence of the -CH2- group introduced between the nitrogen atoms of the ethylenediamine moiety, revealing a neutral form of the potential bidentate ligand.

The synthesis of two new organic compounds, diisobutyl- and diisopentyl (S,S)-alpha(1),alpha(3)-bis(cyclohexylmethyl-1,3-imidazolidinediacetate is reported herein. The one-pot procedure was realized by the addition of the reducing agent and carbonyl compound into a methanolic solution of the parent compounds (isobutyl and isopentyl esters of (S,S)-alpha,alpha '-(1,2-ethanediyldiimino)bis[cyclohexanepropanoic acid] in appropriate stoichiometric ratios. The compounds were fully characterized by infrared, ESI-MS, 1D (H-1 and C-13) and 2D (COSY, HSQC and HMBC) NMR spectroscopy and elemental analysis. The spectral data confirmed the presence of the -CH2- group introduced between the nitrogen atoms of the ethylenediamine moiety, revealing a neutral form of the potential bidentate ligand.

A program was initiated in June 2009 to evaluate the potential of porous organosilicate sorbents in the capture or neutralization of light gas threats. Of primary interest were targets identified by the TIC/TIM Task Force as priority threats. A number of approaches were taken for increasing binding capacity and reactivity in the sorbent materials: grafting of metalloporphyrins, incorporation of sites for metal coordination, and incorporation of acidic and basic groups. In addition, the impact of morphological considerations, such as pore size and organization, were evaluated. Target capture by the sorbents was evaluated using microbreakthrough testing completed at the Edgewood Chemical Biological Center. Development of relevant sorbent morphologies was also pursued. Overall, the sorbents show promise, with several offering improvements in target capture and retention over state-of-the-art materials., The original document contains color images. Prepared in collaboration with Edgewood Chemical Biological Center, Aberdeen Proving Grounds, MD. Sponsored in part by DTRA.

As a consequence of the increasing concern about soil contamination, research on soilremediation technology has grown rapidly. The effects of the chelant dosage, solution pH, soil-to-solution ratio and the dissolved/soil organic matter on metal extraction with the application of ethylene-diamine-tetraacetic acid (EDTA) and [S,S]-stereoisomer of ethylenediaminedisuccinic acid (EDDS) mixture (including individual additions) were investigated through batch and column studies. In addition, soil contaminated with both heavy metals and organic pollutants are commonly found and often require extra effort for remediation. The effectiveness and mechanisms of heavy metal and naphthalene co-removal from artificially contaminated soil by FeEDTA/FeEDDS-activated persulfate were investigated, again through batch studies. Compared with Cu extraction, Pb and Zn extraction exhibit different kinetic behaviors at varying EDDS-to-metal molar ratios (under EDDS deficiency conditions) within two days. The extracted Pb and Zn were readily re-adsorbed onto the soil surfaces over time until reaching an apparent equilibrium between extraction and re-adsorption. In contrast, no re-adsorption occurred for Cu due to its high preference for forming complexes with EDDS. An alkaline pH range was preferable for Pb extraction when the EDDS was deficient, whereas the influence of varying the soil-to-solution ratio under EDDS deficiency was marginal compared with that of the EDDS-to-metal molar ratio and solution pH. Higher Pb extraction by EDDS and EDTA mixture was found compared with individual additions of EDDS or EDTA under chelant deficiency conditions. It appears that the EDDS and EDTA mixture can be utilized for metal extraction in a more efficient way according to their respective affinity towards particular metals, in which Pb is primarily complexed with EDTA, while Cu and Zn bind with both EDTA and EDDS. The synergistic performance of the EDDS and EDTA mixture probably resulted from the chan

As a consequence of the increasing concern about soil contamination, research on soilremediation technology has grown rapidly. The effects of the chelant dosage, solution pH, soil-to-solution ratio and the dissolved/soil organic matter on metal extraction with the application of ethylene-diamine-tetraacetic acid (EDTA) and [S,S]-stereoisomer of ethylenediaminedisuccinic acid (EDDS) mixture (including individual additions) were investigated through batch and column studies. In addition, soil contaminated with both heavy metals and organic pollutants are commonly found and often require extra effort for remediation. The effectiveness and mechanisms of heavy metal and naphthalene co-removal from artificially contaminated soil by FeEDTA/FeEDDS-activated persulfate were investigated, again through batch studies. Compared with Cu extraction, Pb and Zn extraction exhibit different kinetic behaviors at varying EDDS-to-metal molar ratios (under EDDS deficiency conditions) within two days. The extracted Pb and Zn were readily re-adsorbed onto the soil surfaces over time until reaching an apparent equilibrium between extraction and re-adsorption. In contrast, no re-adsorption occurred for Cu due to its high preference for forming complexes with EDDS. An alkaline pH range was preferable for Pb extraction when the EDDS was deficient, whereas the influence of varying the soil-to-solution ratio under EDDS deficiency was marginal compared with that of the EDDS-to-metal molar ratio and solution pH. Higher Pb extraction by EDDS and EDTA mixture was found compared with individual additions of EDDS or EDTA under chelant deficiency conditions. It appears that the EDDS and EDTA mixture can be utilized for metal extraction in a more efficient way according to their respective affinity towards particular metals, in which Pb is primarily complexed with EDTA, while Cu and Zn bind with both EDTA and EDDS. The synergistic performance of the EDDS and EDTA mixture probably resulted from the chan

As a consequence of the increasing concern about soil contamination, research on soilremediation technology has grown rapidly. The effects of the chelant dosage, solution pH, soil-to-solution ratio and the dissolved/soil organic matter on metal extraction with the application of ethylene-diamine-tetraacetic acid (EDTA) and [S,S]-stereoisomer of ethylenediaminedisuccinic acid (EDDS) mixture (including individual additions) were investigated through batch and column studies. In addition, soil contaminated with both heavy metals and organic pollutants are commonly found and often require extra effort for remediation. The effectiveness and mechanisms of heavy metal and naphthalene co-removal from artificially contaminated soil by FeEDTA/FeEDDS-activated persulfate were investigated, again through batch studies. Compared with Cu extraction, Pb and Zn extraction exhibit different kinetic behaviors at varying EDDS-to-metal molar ratios (under EDDS deficiency conditions) within two days. The extracted Pb and Zn were readily re-adsorbed onto the soil surfaces over time until reaching an apparent equilibrium between extraction and re-adsorption. In contrast, no re-adsorption occurred for Cu due to its high preference for forming complexes with EDDS. An alkaline pH range was preferable for Pb extraction when the EDDS was deficient, whereas the influence of varying the soil-to-solution ratio under EDDS deficiency was marginal compared with that of the EDDS-to-metal molar ratio and solution pH. Higher Pb extraction by EDDS and EDTA mixture was found compared with individual additions of EDDS or EDTA under chelant deficiency conditions. It appears that the EDDS and EDTA mixture can be utilized for metal extraction in a more efficient way according to their respective affinity towards particular metals, in which Pb is primarily complexed with EDTA, while Cu and Zn bind with both EDTA and EDDS. The synergistic performance of the EDDS and EDTA mixture probably resulted from the chan

Lipase B from Candida antarctica (CALB) has been modified using succinic polyethyleneglycol via the carbodiimide route. Immobilized enzyme (on octyl Sepharose or Eupergit C) has been used, to take advantage of the solid phase. Modification of immobilized CALB's native amino groups did not produce a significant alteration of CALB. However, if the enzyme was previously aminated, around 14–15 PEG molecules could be introduced per enzyme molecule. Also, it has been found that succinic groups are far more reactive than acetic acid following this strategy. Even after this drastic double modification, the functional properties of the enzyme have not been impoverished to a large extent: stability decreased only to some extent (by a 5–6 fold factor), activity versus some substrates even increased (e.g., around 60% using p-nitrophenyl butyrate). It has been found that both modifications (amination and pegylation) have very different effects on enzyme properties when performed on CALB immobilized on Eupergit C or octyl Sepharose. For example, activity versus pNPP increased using CALB-octyl Sepharose while it decreased when using Eupergit C following amination and PEGylation. The effects also depend on the reaction and substrate, for example in hydrolysis of methyl mandelate, the activity decreased by 50% using CALB-octyl Sepharose after PEGylation of the aminated enzyme, while using CALB-Eupergit C had no effect. In this last case, enantioselecitvity in this hydrolysis significantly improved after both chemical modifications (from 7.5 to 20), while using CALB-octyl Sepharose almost had no effect.

Injectable and settable bone grafts offer significant advantages over pre-formed implants due to their ability to be administered using minimally invasive techniques and to conform to the shape of the defect. However, injectable biomaterials present biocompatibility challenges due to the potential toxicity and ultimate fate of reactive components that are not incorporated in the final cured product. In this study the effects of stoichiometry and triethylenediamine (TEDA) catalyst concentration on the reactivity, injectability, and biocompatibility of two component lysine-derived polyurethane (PUR) biocomposites were investigated. Rate constants were measured for the reactions of water (a blowing agent resulting in the generation of pores), polyester triol, dipropylene glycol (DPG), and allograft bone particles with the isocyanate- terminated prepolymer using an in situ attenuated total reflection Fourier transform infrared spectroscopy technique. Based on the measured rate constants, a kinetic model predicting the conversion of each component with time was developed. Despite the fact that TEDA is a well-known urethane gelling catalyst, it was found to preferentially catalyze the blowing reaction with water relative to the gelling reactions by a ratio 17:1. Thus the kinetic model predicted that the prepolymer and water proceeded to full conversion, while the conversions of polyester triol and DPG were 70% after 24 h, which was consistent with leaching experiments showing that only non-cytotoxic polyester triol and DPG were released from the reactive PUR at early time points. The PUR biocomposite supported cellular infiltration and remodeling in femoral condyle defects in rabbits at 8 weeks, and there was no evidence of an adverse inflammatory response induced by unreacted components from the biocomposite or degradation products from the cured polymer., Published in Acta Biomaterialia, v8 p4405-4416, 5 Aug 2012. Sponsored in part by the Orthopedic Extremity Trauma Research Program.

The Ni(II), Cu(II) and Zn(II) complexes with a tetradentate ligand

The Ni(II), Cu(II) and Zn(II) complexes with a tetradentate ligand

The Ni(II), Cu(II) and Zn(II) complexes with a tetradentate ligand

Ethylenediamine dinitrate (EDDN) (99.5% pure) was tested for clastogenic potential to induce chromosome aberrations in cultured Chinese Hamster Ovary (CHO) cells with and without metabolic activation according to OECD TG 473 in compliance with Good Laboratory Practice,. EDDN was tested at concentrations 500, 1000, 2000, 3000, 4000 and 5000 ug/mL both with and without activation. Based on the cytotoxicity data, chromosome aberrations were scored from the cells treated with the concentrations 1000, 2000, and 3000 ug/mL without activation and 3000, 4000, and 5000 ug/mL with activation. Two hundred metaphases were scored from each concentration and controls. EDDN did not induce a statistically significant increase in the percentage of chromosome aberration, polyploidy and endoreduplicated cells in the CHO cells both with and without activation. A confirmatory chromosome aberration assay was performed without activation also showed negative.

Few studies have considered the environmental impacts of impurities and byproducts associated with low-efficiency nanomanufacturing processes. Here, we study the composition and aquatic toxicity of low-purity, as-produced fullerenes (C60) and metallofullerene waste solids, both of which were generated via arc-discharge synthesis. Scanning electron microscopy with energy dispersive X-ray spectroscopy (SEMEDX)and inductively coupled plasma mass spectroscopy (ICPMS)were used to characterize the metals composition of the solid test materials and of aqueous leachates prepared by mixing test materials with waters of varying pH, hardness, and salinity. The aquatic toxicity of the leachates was determined using U.S. Environmental Protection Agency recommended aquatic bioassay protocols with two standard test organisms-Pimephales promelas and Ceriodaphnia dubia. Results indicated that metals associated with the solid test materials became mobilized in our test system upon interaction with waters of circumneutral pH and reached concentrations sufficient to induce toxicity in both test species. Acute (48 h) LC50 values for P. promelas and C. dubia exposed to leachates prepared from metallofullerene waste solids were 54 and 5% (as % leachate in diluent), respectively. Toxicity was eliminated after adding the chelator EDTA to the leachates, implicating divalent transition metals as the toxicity source. Our results demonstrate the aquatic toxicity of metals mobilized from products and byproducts of nanomanufacturing, and they emphasize the need for a global review of nanomanufacturing wastes and low-purity products., Published in Environmental Science & Technology, v43 n11 p4169-4174, 2009. Prepared in cooperation with NanoSafe, Inc. Blacksburg, VA; and U.S. Army Engineer Research and Development Center, Vicksburg, MS. Government or Federal Purpose Rights License.

The U.S. Army Research Laboratory (ARL) is developing a series of insensitive melt cast explosive formulations to replace the conventional TNT-based fills which fails to meet Insensitive Munitions (1M) requirements. These formulations are based upon a nitrate salt based eutectic mixture called DEMN. These DEMN formulations have previously been demonstrated to have significantly improved 1M response, passing 4 out of 5 1M tests in the 155mm M795 artillery projectile. Two components of this DEMN eutectic are the energetic salts, Ethylenediamine.

Ethylenediamine dinitrate (EDDN) (99.5% pure) was tested forclastogenic potentials to induce micronucleated polychromatic erythrocytes (MPCE) in the bone marrow cells of male and femal CD-1 mice according to OECD TG 474 in compliance with Good Laboratory Practice. Male and female mice were dosed orally at 500, 1000, and 2000 mg/kg. Animals were euthanized approximately 24 and 48 hr after dosing. The percentage of polychromatic erythrocytes (PCE) and frequency of micronucleated polychromatic erythrocyte (MPCE) were determined at 24 and 48 hours. Cytotoxicity was assessed by scoring the number of PCE and norchromatic erythrocyte (NCE) in first 200 erythrocytes for each animal. There were not statistically significant increases in the number of MPCE in the treated groups when compared to the concurrent vehicle control group. These results indicate that EDDN was negative in the in vivo mouse micronucleus assay and therefore is not considered to be a clastogenic agent.

Ethylenediamine dinitrate (EDDN) (99.5% pure) was tested for mutagenic potential with Salmonella typhimurium strains, TA 98, TA 100, TA 1535, TA 1537 and Escherichia coli strain WP2 uvrA by plate incorporation method according to OECD TG 471 in compliance with Good Laboratory Practice, EDDN was tested at doses 100, 500, 1000, 3000 ug/plate and 5000 ug/plate. The results showed that EDDN was not mutagenic in Salmonella typhimurium and Escherichia coli both with and without activation in tster strains (TA 98, TA 1535, and TA 1537) but it showed positive increase in TA 100 tester stain without activation (3.1-fold) at 5000 ug/plate. This was also verified with confirmatory mutation assay at concentrations up to 5000 ug/plate with activation and also found positive (2.5 fold) in TA 100. No positive increases were observed with other tester strains (TA 98, TA 1535, TA 1537) with or without activation. Based on the positive response was only in one strain TA 100 observed at the highest dose under conditions oftest and according to criteria set for evaluating test results, the EDDN was weak positive in this system both with and without activation.

The addition of amines such as ethylenediamine, diethylenetriamine and meramine in the course of carbonation of basic calcium carbonate promoted the formation of a disk-like calcium carbonate which is vaterite and 1-1.5 μm in diameter and 0.1-0.2 μm in thickness. On the other hand, dicarboxylic acids, carboxylic chelate compounds, and amino acids promoted the formation of cubic or spindle-like calcite. Diethylenetriamine which was adsorbed on the surface of calcium carbonate plays an important role in the formation of disk-like calcium carbonate.

N,N,N(prime),N(prime)-tetramethyl ethanediamine (TMEDA, 99.86% pure) was tested for its potentials to induce micronucleated polychromatic erythrocytes (MPCE) in the bone marrow cells of male and female CD-1 mice according to OECD TG 474 in compliance with Good Laboratory Practice. Male and female mice were dosed orally at 62.5,125 and 250 mg/kg. Animals were euthanized approximately 24 and 48 hrs after dosing. The percent of polychromatic erythrocytes (PCE) and frequency of micronucleated polychromatic erythrocyte (MPCE) were determined at 24 and 48 hrs. Cytotoxicity was assessed by scoring the number of PCE and normochromatic erythrocyte (NCE) in first 200 erythrocytes for each animal. There were no statistically significant increases in the number of MPCE in the treated groups when compared to the concurrent vehicle control group. These results indicate that TMEDA was negative in the in vivo mouse micronucleus assay and the compound was not clastogenic.

Uniform ZnSe precursor (ZnSe : 0.38en, en = ethylenediamine) nanoribbon arrays are grown vertically on Zn foils in ethylenediamine (en) using a solvothermal method. After the annealing treatment in N-2, the ZnSe nanoribbon arrays can be obtained without an obvious morphology change and the crystallinity of ribbons is greatly improved. The microstructures of both individual ZnSe precursor and ZnSe nanoribbons are investigated. Field emission characteristics show that the onset field required drawing a current density of similar to 0.1 mu Acm(-2) from the ZnSe nanoribbons is 5.0 V mu m(-1) and the field enhancement factors are determined to be similar to 1382.

Uniform ZnSe precursor (ZnSe : 0.38en, en = ethylenediamine) nanoribbon arrays are grown vertically on Zn foils in ethylenediamine (en) using a solvothermal method. After the annealing treatment in N-2, the ZnSe nanoribbon arrays can be obtained without an obvious morphology change and the crystallinity of ribbons is greatly improved. The microstructures of both individual ZnSe precursor and ZnSe nanoribbons are investigated. Field emission characteristics show that the onset field required drawing a current density of similar to 0.1 mu Acm(-2) from the ZnSe nanoribbons is 5.0 V mu m(-1) and the field enhancement factors are determined to be similar to 1382.

Uniform ZnSe precursor (ZnSe : 0.38en, en = ethylenediamine) nanoribbon arrays are grown vertically on Zn foils in ethylenediamine (en) using a solvothermal method. After the annealing treatment in N-2, the ZnSe nanoribbon arrays can be obtained without an obvious morphology change and the crystallinity of ribbons is greatly improved. The microstructures of both individual ZnSe precursor and ZnSe nanoribbons are investigated. Field emission characteristics show that the onset field required drawing a current density of similar to 0.1 mu Acm(-2) from the ZnSe nanoribbons is 5.0 V mu m(-1) and the field enhancement factors are determined to be similar to 1382.

The effectiveness of using ethylenendiamine modified rice hull (MRH) to remove Basic Blue 3 (BB3) and Reactive Orange (RO16) from single and binary dye solutions was investigated. The optimised modification process was treating 1.00 g of rice hull with 0.02 mol of ethylendiamine (EDA) in a “well stirred” water bath at 80oC for 2 hours. Surface morphology analysis was carried out using scanning electron microscopy (SEM) and atomic force microscopy (AFM). Batch and column studies were performed under various experimental conditions and the parameters studied included pH, contact time, initial concentration, temperature, agitation rate, particle size, sorbent dosage, bed depth, flow-rate and sorption –desorption process. Batch studies reveal that sorption was pH and concentration dependent. The sorption of BB3 and RO16 from single and binary dye solution was found to be endothermic and exothermic, respectively. The kinetics of dye sorption fitted a pseudo-second order rate expression. Maximum sorption capacities calculated from the Langmuir model are 14.68 and 60.24 mg/g for BB3 and RO16, respectively in binary dye solutions. This corresponds to an enhancement of 4.5 and 2.4 folds, respectively, compared to single dye solutions. The dye uptake increased with increasing sorbent dosage. Column studies indicate that breakthrough was bed depth, flow rate and influent concentration dependent. Unusual breakthrough curves were obtained for RO16, with very rapid initial breakthrough followed by complete retention at low flow rate, influent concentration and high bed depth. The breakthrough curves of BB3 followed the typical S shape of packed- bed systems. Theoretical breakthrough curves at different bed depths and flow rates generated by the two parameter mathematical model agreed well with the experimental data of single dye solution of BB3. In sorption-desorption process, BB3 can be recovered completely by eluting the column with 0.5 M H2SO4 and HCl but the column cannot be

The effectiveness of using ethylenendiamine modified rice hull (MRH) to remove Basic Blue 3 (BB3) and Reactive Orange (RO16) from single and binary dye solutions was investigated. The optimised modification process was treating 1.00 g of rice hull with 0.02 mol of ethylendiamine (EDA) in a “well stirred” water bath at 80oC for 2 hours. Surface morphology analysis was carried out using scanning electron microscopy (SEM) and atomic force microscopy (AFM). Batch and column studies were performed under various experimental conditions and the parameters studied included pH, contact time, initial concentration, temperature, agitation rate, particle size, sorbent dosage, bed depth, flow-rate and sorption –desorption process. Batch studies reveal that sorption was pH and concentration dependent. The sorption of BB3 and RO16 from single and binary dye solution was found to be endothermic and exothermic, respectively. The kinetics of dye sorption fitted a pseudo-second order rate expression. Maximum sorption capacities calculated from the Langmuir model are 14.68 and 60.24 mg/g for BB3 and RO16, respectively in binary dye solutions. This corresponds to an enhancement of 4.5 and 2.4 folds, respectively, compared to single dye solutions. The dye uptake increased with increasing sorbent dosage. Column studies indicate that breakthrough was bed depth, flow rate and influent concentration dependent. Unusual breakthrough curves were obtained for RO16, with very rapid initial breakthrough followed by complete retention at low flow rate, influent concentration and high bed depth. The breakthrough curves of BB3 followed the typical S shape of packed- bed systems. Theoretical breakthrough curves at different bed depths and flow rates generated by the two parameter mathematical model agreed well with the experimental data of single dye solution of BB3. In sorption-desorption process, BB3 can be recovered completely by eluting the column with 0.5 M H2SO4 and HCl but the column cannot be

Formation of three Cd(II)-ethylenediamine (en) complexes ([Cd(en)(n)](2+), n = 1-3) in aqueous solution and in DMSO solvent has been established by means of Cd-113 NMR spectroscopy. It is clearly shown that Cd(II)-en complexes form primarily in basic solutions. A correlation between the Cd-113 NMR chemical shifts and the ethylenediamine (en) coordination number has been observed and discussed. Two single crystals with the composition [Cd-2(en)(5)](ClO4)(4) (1) and [Cd(en)(3)](ClO4)(2) (2) were prepared from aqueous solution, and their structures were determined by single crystal X-ray diffraction. Cd(II) ions are coordinated by six atoms in both compounds, I and 2: via five N-donor atoms and one O-donor atom forming a bimetallic complex 1, and via six N-donor atoms forming a distorted octahedral monometallic complex 2. Raman spectra of complexes 1 and 2 also provide additional evidence that the cis-form of the bridging en is present in complex 1., QC 20100525

A novel ternary Tl(III) complex [Tl(en)(2)(CN)](2+) has been synthesized and characterized in solution by NMR and in solid by Raman spectroscopy. This complex has been prepared in the solid state, [Tl(en)(2)(CN)](ClO4)(2) (1), and the related [Tl(tren)(CN)(2)](ClO4) (2), and their crystal structures determined by X-ray diffraction. A linear cyano-bridged supramolecular complex exists in [Tl(en)(2)(CN)](ClO4)(2). In [Tl(tren)(CN)(2)](ClO4), the thallium ion exists in a distorted octahedral geometry cis coordinated cyanides., QC 20100525

The potential of aminated rice hull to remove Cr(VI), Cu(II) and As(V) from aqueous solution was investigated. Amination processes enhanced the sorption capacities of rice hull with ethylenediamine being the most economical and efficient aminating agent. Chemical modification of surface functional groups of ethylenediamine modified rice hull (enRH) indicated that amine and carboxyl groups were the major sorption sites. Both batch and column studies were performed, taking into account parameters such as pH, contact time, initial concentrations, ionic strength, particle size of sorbent, rate of agitation, presence of competitive cation and anions, use of different metal ion sources, sorbent dosage, temperature, bed depth, flow rate and sorptiondesorption process. The results of batch studies indicated that the sorption process was pH and temperature dependent. External mass transfer was not the sole rate-limiting phase and might involve chemisorption. The sorption of metal ions from single metal ion solution was in the order of Cr(VI) > Cu(II) > As(V) which is consistent with the Pearson's theory on hard and soft acid base. Cr(VI) and As(V) sorptions involved electrostatic interactions while Cu(n) sorption involved complexation. Where Cu(n) was present in binary and ternary metal ion solutions, Cr(VI) and As(V) removal also involved complexation. Column studies revealed different equilibrium states compared with batch studies. Breakthrough was bed depth, flow rate and initial concentration dependent. The presence of sulfate significantly affected the breakthrough time of Cr(VI) and Cu(n). The relationship between service time and bed depth was linear. The predicted breakthrough curves obtained from a two-parameter mathematical model agreed well with the experimental values in Cu(II) from all systems and Cr(VI) from binary Cu(II)- Cr(VI) and ternary metal ion solutions when sulfate was absent. Sequential columns could successfully reduce the levels of Cr(VI) and Cu(II)

The potential of aminated rice hull to remove Cr(VI), Cu(II) and As(V) from aqueous solution was investigated. Amination processes enhanced the sorption capacities of rice hull with ethylenediamine being the most economical and efficient aminating agent. Chemical modification of surface functional groups of ethylenediamine modified rice hull (enRH) indicated that amine and carboxyl groups were the major sorption sites. Both batch and column studies were performed, taking into account parameters such as pH, contact time, initial concentrations, ionic strength, particle size of sorbent, rate of agitation, presence of competitive cation and anions, use of different metal ion sources, sorbent dosage, temperature, bed depth, flow rate and sorptiondesorption process. The results of batch studies indicated that the sorption process was pH and temperature dependent. External mass transfer was not the sole rate-limiting phase and might involve chemisorption. The sorption of metal ions from single metal ion solution was in the order of Cr(VI) > Cu(II) > As(V) which is consistent with the Pearson's theory on hard and soft acid base. Cr(VI) and As(V) sorptions involved electrostatic interactions while Cu(n) sorption involved complexation. Where Cu(n) was present in binary and ternary metal ion solutions, Cr(VI) and As(V) removal also involved complexation. Column studies revealed different equilibrium states compared with batch studies. Breakthrough was bed depth, flow rate and initial concentration dependent. The presence of sulfate significantly affected the breakthrough time of Cr(VI) and Cu(n). The relationship between service time and bed depth was linear. The predicted breakthrough curves obtained from a two-parameter mathematical model agreed well with the experimental values in Cu(II) from all systems and Cr(VI) from binary Cu(II)- Cr(VI) and ternary metal ion solutions when sulfate was absent. Sequential columns could successfully reduce the levels of Cr(VI) and Cu(II)

The formation of three [TI(en)(n)](3+) complexes (n = 1-3) in a pyridine solvent has been established by means of Tl-205 and H-1 NMR. Their stepwise stability constants based on concentrations, K-n = [Tl(en)(n)(3+)]/{[Tl(en)(n-1)(3+)](.)[en]}, at 298 K in 0.5 M NaClO4 ionic medium in pyridine, were calculated from Tl-205 NMR integrals: log K-1 = 7.6 +/- 0.7; log K-2 = 5.2 +/- 0.5 and log K-3 = 2.64 +/- 0.05. Linear correlation between both the Tl-205 NMR shifts and spin-spin coupling Tl-205-H-1 versus the stability constants has been found and discussed. A single crystal with the composition [Tl(en)(3)](ClO4)(3) was synthesized and its structure determined by X-ray diffraction. The Tl3+ ion is coordinated by three ethylenediamine ligands via six N-donor atoms in a distorted octahedral fashion., QC 20100525

An ion-selective reference probe which is adapted for use with potentiometric measurement systems is disclosed. The reference probe is non-chloride based and employs a-specially adapted electrolyte which is reversible (i.e. with regard to ionic activity). More particularly the electrolyte includes appropriate concentrations of ethylenediamine and copper(II) ions in a solvent to permit reversibility of the electrolyte within a desired range. Junction potential between the electrolyte and a test solution is minimized by forming the electrolyte from a portion of the test solution., Supersedes PAT-APPL-219 680-94.

This report presents the results of an Idaho National Engineering Laboratory (INEL) study of three electrolytic silver strippers that were tested in addition to three new immersion nickel strippers. Two nickel strippers successfully completed field testing last year. Frederick Gumm's CELOP 204 and Electrochemicals, Nickel-Sol were placed in service in the plating shop at Kelly AFB July through September 1990. This research has yielded at least one formulation (containing ethylenediamine sodium m-nitrobenzenesulfate, nitric acid, sodium nitrate, and ammonium thiocyanate) worthy of field testing. The formulation is for stripping electrolytic nickel. Other formulations, especially those for stripping electroless nickel, need further investigative work. A byproduct of the field test stripping process above is redwater in the waste stream. An investigation was unable to identify the chemical species responsible for the colored water. The report recommends (1) that at least one generic nickel stripper formulation be field tested, (2) one of the silver strippers 1(McGean-Rohco's Rostrip 999-SP) be implemented at the ALC, and (3) further attempts be made to discover the source of the redwater in the waste stream. jg p.3