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Among the postharvest pathogens of apple fruit, Penicillium expansum (P.expansum) is considered to be one of the most common fungal pathogens worldwide. It is the causal agent of blue mold decay; the main serious economically disease of apple fruits, and the main producer of patulin (PAT). The principal objective of this work was to evaluate the aggressiveness and the PAT production of three isolated strains from apples produced in the East of Algeria. These strains were isolated then screened for their inhibitory activity against Escherichia coli and Bacillus subtilis (18 mm and 18 mm for S7; 10 mm and 11mm for S3), as well as their ability to cause blue rot (S4). The three strains S7, S3, and S4 (MN904448, MT023795 and MN904449, respectively) were identified as P. expansum by ITS1, ITS4, and β-tubulin gene sequences analysis. The in vitro ability to produce PAT was confirmed by Gas chromatography-mass spectrometry of strains’ crude extracts cul-tured on YES (Yeast-Extract-Sucrose) medium. Indeed, these strains exhibited a great capacity to cause blue mold decay for all tested apples (26 to 52 mm lesion diameter), after nine days of incubation at 25°C. Apples rotten area analysis that was performed by UPLC analysis revealed that these three strains were able to produce PAT at different concentrations ranging from 0.57 to 469 μg/mL. Thus, these strains constitute a risk to consumer health because these amounts exceed the permissive level of PAT.

Brown rot disease of Canino apricots and FlordaPrince peaches is a major serious decay disease during cold storage in Egypt and worldwide, Infection of stone fruits may occur during blooming until harvest harvest which cause decay during cold storage. The effect of fungicide safe alternatives, (Chemical salts and Inducing resistance). The effect of fungicide safe alternatives, i.e. sodium bicarbonate, calcium chloride, potassium sorbate, potassium silicate,boric acid and salicylic acid, on growth of Monilinia laxa M. fructigena and Monilinia sp. as major pathogens on apricots and peaches ,was investigated at different concentrations ranged from 1000 ppm to 5000 ppm amended in PDA in vitro. Sodium bicarbonate at 1000 ppm completely suppressed the growth of the three isolates of Monilinia spp., Calcium chloride at 1000 ppm to 5000 ppm, did not show any suppression of M. laxa or Monilinia sp., while it suppressed M. fructigena when used at ≥4000 ppm. Potassium silicate did not show considerable effectiveness against different tested isolates of Monilinia spp. IC50 values (chemical concentration that reduce fungal growth to 50%) of sodium bicarbonate, potassium sorbate and salicylic acid on M. fructigena were less than 1000 ppm. On M. laxa, only sodium bicarbonate showed IC50 less than 1000 ppm, while the IC50 values of potassium sorbate and boric acid were less than 2000 ppm. Regarding Monilinia sp. sodium bicarbonate and potassium sorbate IC50 values were less than 1000 ppm. Generally, sodium bicarbonate, potassium sorbate and salicylic acid showed IC50 values less than 1000 ppm, 2000 ppm, and 3000 ppm, respectively. These salts and inducers at 3000 ppm, were used as three preharvest sprays starting at growth stage no. 64 and then repeated twice at 10 days intervals in orchard located at Qualyubia and Ismailia, during seasons 2015 and 2016. These salts and acids were also adopted at 3000 ppm on naturally infected or artificially inoculated fruits after harvest at growth stage no. 81 during season 2016. Sodium bicarbonate, calcium chloride, potassium sorbate and boric acid were the most effective treatments to control brown rot disease on apricots and peaches during cold storage at 0oC and 90% RH for 15 days and 30 days, either these chemicals were sprayed preharvest or adopted after harvest. These treatments maintained fruit quality regarding firmness and acidity.

A challenge in glass engineering is the design of molecular glasses combining a high glass kinetic stability (GS) of the amorphous phase with a low (sub-ambient) glass transition temperature (Tg). Triazine derivatives with arylamino substituents readily form glassy phases that can show outstanding resistance to crystallization. In the present study, a series of 12 analogous compounds incorporating phenylamino and cyclohexylamino groups was synthesized, and their thermal properties and intermolecular interactions were studied. All compounds possess an excellent glass-forming ability, a low Tg ranging from 32 °C to as low as −19 °C, and a high GS. While the cyclohexyl derivatives show higher Tg, the phenyl derivatives possess a higher GS with some compounds remaining completely amorphous for over three years despite their sub-ambient Tg. X-ray diffraction, infrared spectroscopy and DFT calculations reveal that the higher volume occupancy and rotational energy barrier of cyclohexyl groups are the main factors responsible for the compounds' higher Tg values but that they also contribute to their higher propensity to crystallize. In counterpart, the planarity of phenyl groups leads to poorer packing and enhances their GS while keeping their Tg well below ambient. The formation of hydrogen bonds or competing interactions provides an additional handle to tune the Tg of the compounds. Taken together, these studies provide guidelines for the design of molecular glasses with readily tunable thermal properties in view of their functionalization.

Еssеntial oils (ЕOs) from cinnamon (Cinnamon zylanicum), clovе (Syzygium aromaticum) camphor (Еucalyptus globulus), and rockеt (Еruca sativa), wеrе еvaluatеd for thеir botryocidal еffеct. In-vitro, Botrytis cinеrеa was еxposеd to 4 diffеrеnt concеntrations of ЕOs, using thrее diffеrеnt tеchniquеs, i.е. amеndеd mеdium, vapourisation, and volatilising. Cinnamon and clovе ЕOs wеrе thе highеst tеstеd concеntrations found to bе thе most еffеctivе in all tеchniquеs which complеtеly inhibitеd 100% of radial growth for B. cinеrеa in vitro. A post-harvеst trial to control grеy mould on grapе bunchеs of Flamе sееdlеss and Supеrior sееdlеss cvs. were conductеd using cinnamon and clovе oils in sеasons 2014 and 2015. Both of the two ЕOs wеrе usеd at concеntrations of 25, 50 and 100 µL./L-1air v/v, еxposеd as vapour trеatmеnt significantly supprеssеd grеy mould during thе cold-storagе. Thеrе was not a significancе diffеrеncеs obsеrvеd among both ЕOs trеatmеnts. Howеvеr, cinnamon at 100 µL.1L-1air v/v was thе most еffеctivе trеatmеnt to control grеy mould of both grapе cultivars

In this study, chemical and bio-control agents were evaluated for their efficiency to control of citrus fruit-rot disease caused Alternaria citri (K2) both, in vitro and in vivo trials. The most effective fungicides were score, montro and Iprodione compared with other fungicides depend on Ec50 and Ec90. While, the fungicide Pyraclostrobine had moderate effect on linear growth of A. citri. Meanwhile, the Coprax, Coprareekh and Azoxystrobine were the least effective fungicide at Ec90. Trichoderma harzianum and Bacillus subtilis tested showed antagonistic action effect to a highly pathogenic isolate of Alternaria citri, with different degrees of inhibition. T. harzianum was the most effective compared with B. subtilis, in vitro trials. Also, all fungicides were evaluated on incidence of citrus fruit rot disease in vivo trials. The disease incidence was reduced, but with different degrees. In addition, using T. harzianum, B. subtilis, B. megaterium (Bio-ARC) and Trichoderma album (Bio-Zeid) decreased incidence of citrus fruit rot disease. On the other side, T. harzianum showed the highest suppressive effect against citrus fruit rot pathogen. Generally, all tested fungicides and bio-agents were effective against the causal fungus in vitro and in vivo trials, but with different degrees.

Calycotome spinosa (L.) Link is one of the important plants in traditional medicine especially in Algeria. The present work deals with the phytochemical screening, the flavonoids extraction from leaves and flowers of this plant, the quantification of total polyphenols and flavonoids, as well as the evaluation of antioxidant and antimicrobial properties of ethyl acetate and n-butanol fractions. While, the rest, interacted with its phenolics identification. The results of preliminary phytochemical screening showed that C. spinosa contained various metabolites: Polyphenols, flavonoids, alkaloids, saponins etc. In addition, the findings of polyphenols determination using Folin Ciocalteu was high in all the fractions: 107.75±0.41 and 64.24±1.81 mg gallic acid equivalents/g extract for leaves ethyl acetate and n-butanol respectively and 81.45±0.6 and 96.06±2.72 mg gallic acid equivalents/g extract for flowers ethyl acetate and n-butanol successively. Conversely, the flavonoids content in the four fractions by AlCl3 was less important than polyphenols. Moreover, the obtained fractions were evaluated for their antioxidant capacity using DPPH assay. Besides, the obtained result revealed that Ethyl acetate and n-butanol fractions of leaves exerted very high antioxidant activities with IC50 equal to 45.25±1.8 and 52.80±2.05 µg/mL, respectively compared with flowers. Furthermore, the antimicrobial activity of those fractions against many microbial strains have also been investigated using the disc diffusion method; the leaves ethyl acetate fraction showed the highest activity against Acinetobacter baumannii with a zone inhibition diameter equal to 22±0.06 mm. Additionally, high-performance liquid chromatography/diode-array detector (HPLC/DAD) analysis performed with C. spinosa fractions revealed the richness of plant in many phenolic compounds. Key words: Calycotome spinosa (L.) Link, medicinal plant, phenolics and flavonoids content, antioxidant activity, antimicrobial potential, high-performance liquid chromatography/diode-array detector (HPLC/DAD).

Several Bacillus strains were isolated from “Ouled Yelass” hot spring soil, located in Setif city (Eastern Algeria). Three isolates of them coded (4RH), (14 RH), and (Set-oxy), were screened for their ability to inhibit the growth of some phytopathogenic fungi, such as Fusarium oxysporium, Botrytis cinerea, Aspergillus niger, Cladosporium cucumerinium and Alternaria alternata. The molecular identification of the strain (4RH) based on the 16S-DNA and gyrase-A genes sequences analysis, showed that it is closely related (99.9%) to the Bacillus amyloliquefaciens species. This bacterium was characterized by a high sporulation yield reaching 22±0.86 × 108 spores/ml and had important inhibition rates up to 80 and 70%, against F. oxysporium and B. cinerea, respectively. The bacterium (4RH) was able to produce cell wall degrading enzymes of cellulase and protease, in contrast to chitinase activity which was negative. Furthermore, it produced the three lipopeptides families, which are, iturins A (C14; C15), fengycin A (C14, C15, C16, C17, and C18), and surfactin (C12, C13, C14, C15, C16). Interestingly, LC-MS profiles of 80% acetonitrile fengycin extract of the (4RH) strain, showed the presence of some new molecular ions (MH+) with masses different, but near to conventional fengycin variants, which correspond to new variants described for the first time in this work. The isolate (4RH) produced 5 µg/ml of the phytohormone (IAA), on TGE medium and siderophores with more than 10 mm of yellow-orange zones, on CAS medium. To conclude, B. amyloliquefaciens (4RH) strain possessed interesting biocontrol and biofertilization characteristics, in vitro, in addition to its high sporulation yield, which make it a potential agent for future biopesticide that could be efficient in the integrate pest management and organic agricultural production systems. Key words: Bacillus, biocontrol, biofertilization, plant protection, hot spring, lipopeptides.

Metal-organic frameworks (MOFs) have emerged as an important class of hybrid organic-inorganic materials. One of the reasons they have gained remarkable attention is attributed to the possibility of altering them by postsynthetic modification, thereby providing access to new and novel advanced materials. MOFs have been applied in catalysis, gas storage, gas separation, chemical sensing, and drug delivery. However, their bactericidal use has rarely been explored. Herein, we developed a two-step process for the synthesis of zirconium-based MOFs metalated with silver cations as a potent antibacterial agent. The obtained products were thoroughly characterized by powder X-ray diffraction, scanning electron microscopy, UV-visible, IR, thermogravimetric, and Brunauer-Emmett-Teller analyses. Their potency was evaluated against E. coli with a reported minimal inhibitory concentration and minimal bactericidal concentration of as low as 6.5 μg/mL of silver content. Besides the novelty of the system, the advantage of this strategy is that the MOFs could be potentially regenerated and remetalated after each antibacterial test, unlike previously reported frameworks, which involved the destruction of the framework.

The aim of this study is to explore the impact of Lycium halimifolium Mill leaves extracts on mycotoxin B1 production in vitro, as well as the inhibitor effect of the aflatoxin B1 synthesis by Aspergillus flavus strain. The strain was isolated, identified (gi |146746162 | EF409803.1.) and positively tested for the production of Aflatoxin B1. The antimycotoxinogenesis effect was investigated using L. halimifolium Mill leaves consisting of butanol and ethyl acetate fractions. Indeed, the fractions were tested to stop the secretion of aflatoxin B1 by A. flavus in submerged culture (YES), simultaneously. The growth of the strain was evaluated as biomass response. The antimycotoxinogenesis activity showed that the two fractions: ethyl acetate and butanol of L. halimifolium Mill leaves were able to inhibit significantly the synthesis of mycotoxin AFB1. Thus, the secretion inhibition percentage was calculated in comparison with the control, using HPLC-PDA technique, and estimated at 96.83% for butanolic fraction and 94.99% for ethyl acetate fraction. To verify its correlation with biomass, the growth inhibition percentage was also estimated. The results showed that the dry weight concentration under butanolic and ethyl acetate fractions was 1.6 and 2 g/l, respectively, corresponding to 65.22 and 56.53% of inhibition growth percentage. Key words: Aflatoxin B1, antimycotoxinogenesis activity, high performance liquid chromatography coupled with photodiode array detector (HPLC-PDA), natural extract.

Synthesis, characterization, corrosion inhibition as well as antimicrobial activity of the coordination compounds {Co(bbms)Cl2}, {Zn(bbms)Cl2}, {Co(btmb)Cl2} and {Zn(btmb)Cl2} containing benzimidazole thioether have been described. Co(bbms) and Zn(bbms) as well as Co(btmb) and Zn(btmb) are isostructural with space group Pbca and P21 respectively. The coordination polyhedron around the metal center for all complexes may be described as a quasi-regular tetragonal geometry. The corrosion inhibition study of these complexes for steel in 0.5 M H2SO4 medium has been investigated using potentiodynamic polarization and EIS techniques. These later show the corrosion inhibition ability of the prepared complexes for steel in acid medium. A new procedure has been developed for antimicrobial assay using a solid tablet of the corresponding complexes. These later show moderate to significant antimicrobial activities against: Pseudomonas syringae, Staphylococcus aureus and Pichia caribbica. DFT/BP86 calculations have been carried out on the neutral complexes and on the monoanionic of (1) and (3) forms of singlet and triplet species. The optimized structures reproduce those observed experimentally, while the reduced ones undergo remarkable geometrical parameters variations.

Current research on metal-organic framework (MOF) luminescent sensing probes focuses on the design of three-dimensional bulk-sized MOFs that in return limits their up-close interactions with targeted guest molecules. In this work, we report a two-dimensional (2D) copper-based metal-organic framework, namely, AUBM-6, synthesized via solvothermal method from isonicotinic acid linker and copper(II) ion. The resulting 2D-layered MOF crystals were highly fluorescent in their exfoliated form and, therefore, explored for detecting several solvents, where a ratiometric selectivity was shown toward acetone. Metal ion sensing was also performed, by which fluorescent detection was observed to have the highest turn-off quenching efficiency toward Pd2+.

The growth kinetics and modeling of ethanol production from inulin by Pichia caribbica (KC977491) were studied in a batch system. Unstructured models were proposed using the logistic equation for growth, the Luedeking-Piret equation for ethanol production and modified Leudeking-Piret model for substrate consumption. Kinetic parameters (X0, μm, m, n, p and q) were determined by nonlinear regression, using Levenberg-Marquart method implemented in a Mathcad program. Since the production of ethanol was associated with P. caribbica cell growth, a good agreement between model predictions and experimental data was obtained. Indeed, significant R2 values of 0.91, 0.96, and 0.95 were observed for biomass, ethanol production and substrate consumption, respectively. Furthermore, analysis of variance (ANOVA) was also used to validate the proposed models. According to the obtained results, the predicted kinetic values and experimental data agreed well . Finally, it is possible to predict the development of P. caribbica using these models. Key words : Pichia caribbica, inulin, bioethanol, numerical simulation.

The soil bacteria, CWBI-B1567 and CWBI-B1568, isolated from arid regions and identified as Bacillus subtilis (accession number KC341751) and Bacillus mojavensis (accession number KC341749) respectively, were screened and evaluated for their antifungal activity against Candida albicans, one of the most important human fungal pathogens. In vitro assay with the antagonists and their cell-free culture supernatants on agar plates showed that the two Bacillus strains effectively inhibited growth of the yeast. The capacity of these Bacillus strains to produce the cell-wall degrading enzymes was further studied. B. subtilis and B. mojavensis are able to produce cellulase and protease, but not chitinase. Bioactive molecules were produced by B. subtilis CWBI-B1567 and B. mojavensis CWBI-B1568 in a liquid culture medium optimised for lipopeptide production. The antifungal activity was equally demonstrated by testing the resulting supernatants and lipopeptide-enriched extracts. The electro-spray mass spectrometry coupled to liquid chromatography (ESI-LC-MS) analysis showed that both the B. subtilis and the B. mojavensis produced surfactin and iturin. However the fengycin group was produced only by B. mojavensis. Through this study, we have demonstrated that B. subtilis and B. mojavensis have a strong antifungal activity especially against C. albicans. This growth inhibition is probably due to the production of cell-wall degrading enzymes and different families of lipopeptide including iturins, fengycins and surfactins. Key words: Bacillus subtilis CWBI-B1567, Bacillus mojavensis CWBI-B1568, antifungal activity, Candida albicans, lipopeptides, electro-spray mass spectrometry coupled to liquid chromatography (ESI-LC-MS), arid regions.

Lactic bacteria are used in fermentation and food bio‐preservation through their production of organic acids and other antimicrobial substances like bacteriocins which restrain certain fungal strains. The main objective of this study is the isolation of Lactobacillus strains from curdled milk samples, in order, to inhibit, in vitro, mycotoxins production by Aspergilus flavus. Six bacterial isolates were obtained from curdled milk commercialized in the region of Constantine. Among them, one isolate coded (B6) had a significant inhibitory effect against A. flavus (the diameter of colony not exceeding 1.5 cm after 72 hr of incubation at 28°C). This isolate (B6), was identified morphologically and biochemically. The obtained results showed that this bacterial isolate belongs Lactobacillus genus. In addition, its antimycotoxinogen activity had been confirmed using some test bacteria, such as E. coli, Staphylococcus aureus, Klebsiella sp., and Pseudomenas syringae. PRACTICAL APPLICATIONS: This paper describes the isolation of lactic bacteria strains from Algerian curdled milk and the study of their antifungal and antimycotoxinogen activity. The method used to test the effect of lactic bacteria strains against toxigenic fungi was not previously exploited. The main objectives were to: (a) Isolate and select the lactic bacteria from curdled milk; (b) Isolate and identify the toxigenic fungi; (c) Select bacterial isolates for antifungal effect against toxigenic fungi; (d) Study of their antimycotoxinogen activity, in vitro.

This study reported the effect of interaction between cytokinins and auxins to enhance accumulation of alkaloids in White henbane (Hyoscyamus albus L.). Plants of this specie were grown under controlled conditions and treated with plant-hormones: Auxins by: 2, 4-Dichlorophenoxyacetic acid (2, 4-D) and 3-Indole Acetic Acid (IAA), Cytokinins by: Kinetin (K) and Benzyl Amino Purine (BAP), at 0-10 and 20 mg L(-1) rates isolated and interacted. The results showed that treatment of 2, 4-D and K at the highest applied rates 20 mg L(-1) increased the accumulation threefold rate estimated to 2.321% in the root plant part and 1.702% in the aerial plant part with the same plant-hormones but dosage of (20x10 mg L(-1)) in order. The TLC for alkaloid extracts shows that H. albus L. contains 6 alkaloids. In this study, it was concluded that the treatment with interaction of (Kx2,4-D) (20x20 mg L(-1)) gives the highest percent of alkaloids in the root and shoot parts compared to plant-hormones separated. The in vitro antibacterial activity was determined on microorganisms: Pseudomonas stutzeri, Staphylococcus aureus, Escherichia coli and Klebsiella pneumoniae. And performed by disc diffusion assay. Respectively, ethanol extracts showed no inhibitory effect on the microorganisms, however alkaloid extracts of H. albus L. of the same treatments with plant-hormones of shoot and root parts showed antibacterial activity against microorganisms that were tested. The results obtained in the present study suggest that alkaloid of H. albus L. can be used in treating diseases caused by the test organisms.

ÖZET Bu doktora tezi dört bölümden oluşmaktadır. İlk bölümde, makroçaprazbağlayıcılar (MCR) sentezlenmiş ve sürenin polimerizasyonunda kullanılarak, çapraz bağlı polimerik mikroküreler sentezlenmiştir. Çapraz bağlayıcı olarak kullanılan MCR'lerin mol kütlelerine bağlı olarak polimer dönüşüm oram, çapraz bağlanma dereceleri ve denge şişme oranlan belirlenmiştir. İyon değiştirici reçinelerin sentezlenmesi için, dumanlı sülfürik asit (oleum) kullanılarak, çapraz bağlı polimerik mikrokürelere sülfo grupları takılmıştır. Polimerik ürünlerin karakterizasyonunda FTIR, NMR ve elementel analiz yöntemleri kullanılmıştır. İkinci bölümde, N-Vinil imidazol (N-VİM) ve çapraz bağlayıcı olarak etilenglikol dimetakrilat (EGDMA) kullanılarak, süspansiyon polimerizasyon yöntemiyle çapraz bağlı poli (etilenglikol dimetakrilat-N-vinil imidazol) [poli(EGDMA-N-VİM)] kopolimer mikroküreler sentezlenmiştir. Bu polimerin karakterizasyonunda FTIR, elementel analiz ve SEM yöntemlerinden yararlanılmıştır. Üçüncü bölümde, sentezlenen iyon değiştiricilerin Cr(III), Cu(II), Zn(II) ve K(I) metal iyonlarına karşı seçimlilikleri incelenmiş, seçimlilik sırasının Cr(III) > Cu(II) > Zn(II) > K(I) şeklinde olduğu belirlenmiştir. Dördüncü bölümde, poli(EGDMA-N-VİM) çapraz bağlı kopolimer mikrokürelerin Cr(III), Cu(II), Zn(II) ve K(I) metal iyonlarına karşı seçimlilikleri incelenmiş ve seçimliliğin Cu(II) > Zn(II) > Cr(III) > K(I) sırasında olduğu belirlenmiştir. Bu sonuçlar, reçinelerin iyon değişimi (toplam adsorpsiyon) özellikleri ile karşılaşünlmıştir. ANAHTAR KELİMELER: Adsorpsiyon, İyon değişimi, Metal uzaklaştırma, Şelat küreler, Makroçaprazbağlayıcılar, Krom(III), Bakır(II), Çinko(II), Potasyum(I), N-Vinil imidazol. ABSTRACT In this Ph.D. thesis, there are four main parts. Firstly, macrocrosslinkers (MCR) were prepared and crosslinked polymeric microbeads was obtained by using these MCRs in polymerization of styrene. Equilibrium swelling ratios, crosslinking degree and ratio of polymer transformation were determined depending on molecular mass of the MCRs used as crosslinkers. In order to synthesis of ion-exchange resins, sulpho groups were attached by using oleum. FTIR, NMR, elemental analysis methods were used for the charactherization of polymeric products. In the second part, crosslinked poly(EGDMA-VIM) [poly(ethylenglycole dimethacrylate-N-vinyl imidazole)] copolymer microbeads was prepared with suspension polymerization method which was the ethylenglycole dimethacrylate (EGDMA) used as a crosslinker. The characterization of this copolymer was made by using FTIR, elemental analysis and SEM methods. Thirdly, affinity of synthesized ion-exchangers to Cr(III), Cu(II), Zn(II) ve K(I) metal ions was investigated and the order of affinity was found as Cr(III) > Cu(II) > Zn(II) > K(I), respectively. Finally, affinity of crosslinked poly(EGDMA-VIM) copolymer microbeads to Cr(III), Cu(II), Zn(II) ve K(I) metal ions was investigated and the order of affinity was found as Cu(II) > Zn(II) > Cr(III) > K(I), respectively. These results were compared with ion- exchange (total adsorption) properties of resins. KEY WORDS: Adsorption, ion-exchange, Metal removal, Chelate beads, Macrocrosslinkers, Crom(III), Copper(II), Zinc(II), Potasium(I), N- Vinyl imidazole. 240

ÖZET Amidoksimlerin teknolojide pekçok uygulama alanı vardır. Birkaç aromatik amidoksimin yağ devir sisteminde korrozyonu önlediği bilinmektedir. Amidoksimler başlıca polimer kimyasında kullanılırlar. Deniz suyundan uranyum elde edilişindeki önemi nedeniyle bu alanda ciddi araştırmalar yapılmakta olup, poliakriloamidoksimler en iyi adsorbanlar arasında yer almaktadır. Bu çalışmada birkaç yeni amidoksim hidroksimik asid klorürlerinin primer veya sekonder aminlerle reaksiyonundan elde edildiler. Bu bileşiklerin yapıları İR, NMR ve kütle spektrumları ile belidendiler. ABSTRACT Amidoximes have found numerous technological applications. Several aromatic amidoximes inhibit corrosion effect in oil circulating systems. Amidoximes are mainly used in polimer chemistry. The importance of a possible uranium recovery from seawater has led to serious investigations `` in that field and polyacrylamidoximes were classified among the best adsorbents. In this work several new amidoximes are obtained from the reaction of hydroximic acid chlorides with primary or secondary amines. The structure of these compounds are determined by İR, NMR and mass spectra. 68

Previous studies have shown that fosetyl-Al (and its active component H3P03) has little in vitro effect on mycelium growth of most Oomycete, while controlling a number of diseases they cause in plants. We have shown previously that preinoculation of Citrus leaves floated on fosetyl-Al or H3P03 with the H3P03-sensitive strain of P. citrophthora (P35), not only inhibited infection by the sensitive strain, but also prevented subsequent infection by the H3P03-insensitive mutant (PAD) of the fungus.

Bu çalışma, 14-19 Ekim 2015 tarihlerinde Kemer[Türkiye]’düzenlenen 2. International Conference on Computational and Experimental Science and Engineering (ICCESEN) Kongresi‘nde bildiri olarak sunulmuştur. Poly(ethylene glycol dimethacrylate-co-1-vinyl-1,2,4-triazole/carbon nanotube, single-walled)/n-GaAs ([P(EGDMA-VTAZ)-CNSW]/n-GaAs) diode was fabricated by using surface polymerization method. Electrical properties were carried out at several temperatures. Dark current mechanisms were investigated by using current-voltage (I-V) measurements. It was shown that the fabricated structure exhibited rectification behaviour that makes it a good candidate for electronic device applications.

This experimental infection study focuses on a specific Salmonella micro-organism commonly found inside hens' eggs. It outlines the application of polyethylene glycol-based films on hens' eggs and microbial growth introduced via transovarian contamination. Three molecular weights of polyethylene glycol ( PEG) were studied: ranging from 1000 g/mol to 3000 g/mol. PEG coating ratios averaged a PEG film thickness of 0.014 +/- 0.006 mm and average eggshell thickness was 0.32 +/- 0.022 mm. The effects of molecular weight of PEG coating and storage time on the growth of Salmonella enteritidis of PEG-coated eggs were evaluated during 30 days of incubation in 37 degrees C storage. The initial concentration of 8 log(10) CFU/mL was achieved by inoculation. The lowest level of S. enteritidis at the end of 30-day incubation period was 5.07 +/- 0.03 log(10) CFU/mL, giving an inhibition efficiency of 33.83%. This level was achieved with a PEG coating of 1.0449 +/- 0.005 density and 0.02 +/- 0.01 film thickness. BAVEF Agricultural Products, Industry & Trade Company

This study is aimed at the synthesis and characterization of the mesoporous magnetic-poly(divinylbenzene-1-vinylimidazole)[m-poly(DVB-VIM))microbeads(average diameter = 53-212 mu m); their application as adsorbent in the removal of Cu(II) ions from aqueous solutions was investigated. The mesoporous m-poly(DVB-VIM) microbeads were prepared by copolymerizing of divinylbenzene (DVB) with 1-vinylimidazole (VIM). The mesoporous m-poly(DVB-VIM) microbeads were characterized by N-2 adsorption/desorption isotherms, ESR, elemental analysis, scanning electron microscope (SEM), and swelling studies. At fixed solid/solution ratio the various factors affecting adsorption of Cu(II) ions from aqueous solutions such as pH, initial concentration, amount of mesoporousm-poly(DVB-VIM)) microbeads, contact time, and temperature were analyzed. Langmuir, Freundlich, and Dubinin-Radushkvich isotherms were used the model adsorption equilibrium data. The Langmuir isotherm model was the most adequate. The pseudo first-order, pseudo-second-order, Ritch-second-order, and intraparticle diffusion models were used to describe the adsorption kinetics. The experimental data fitted to pseudo second-order kinetic. The study of temperature effect was quantified by calculating various thermodynamic parameters such as Gibbs free energy, enthalpy, and entropy changes. Morever, after the use in adsorption, the mesoporous m-poly(DVB-VIM) microbeads with paramagnetic property was separated via the applied magnetic force. These features make the mesoporous m-poly(DVB-VIM) microbeads a potential candidate for support of Cu(II) ions removal under magnetic field.

The adsorption of poly(1-vinylimidazole) (PVI) onto sepiolite from aqueous solutions was investigated as a function of some parameters such as pH, ionic strength, and temperature. The adsorption of PVI was increased with increasing pH and with decreasing ionic strength and temperature. The Langmuir isotherm model fitted the isotherm data better than the Freundlich model. The electrophorotic mobility of sepiolite dispersions was measured at different PVI concentrations and pH. The thermodynamic parameters Gibbs free energy, enthalpy, and entropy were evaluated. The dimensionless separation factor (R-L.) revealed that sepiolite can be used for adsorption of PVI from aqueous solutions. The second-order kinetics equation best fitted the experimental data. Dielectric properties of sepiolite coated with PVI have been also investigated. The sample with adsorbed PVI at 25 degrees C has the maximum the AC conductivity and the charge carriers can move easily in comparison with other samples. The real permittivities of the PVI-adsorbed samples are quite high in comparison with those of the pure polymer as a result of interface interactions. Kocaeli Üniversitesi -2007/071 Balıkesir Üniversitesi Uygulamalı Bilimler Araştırma Merkezi (BURCAS)

The magnetic-poly(divinylbenzene-4-vinylpyridine) [m-poly(DVB-4VP)] microbeads (average diameter: 180–212 μm) were synthesized by copolymerizing of divinylbenzene (DVB) with 4-vinylpyridine (4VP) and by mixing this copolymer with Fe 3 O 4 nanoparticles. The resultant material was characterized by N 2 adsorption/desorption, ESR, elemental analysis, scanning electron microscope (SEM) and swelling studies. After functionalized with sulfonic acid, m-poly(DVB-4VP-SO 3 H) was characterized by FT-IR and TGA analysis. The results showed that both of Fe 3 O 4 and –SO 3 H are bonded to the polymer successfully. N 2 adsorption/desorption isotherms of synthesized samples had the hysteresis behaviour associated with mesoporous materials (pore diameter: 3.73 nm). Sulfonic acid functionalized mesoporous m-poly(DVB-4VP-SO 3 H) has been demonstrated to have higher reactivity than commercially available solid acid catalysts for the conversion of propionic acid to methyl ester. The apparent activation energy was found to be 38.5 kJ mol −1 for m-poly(DVB-4VP-20%SO 3 H). The catalyst showed negligible loss of activity after four repetitive cycles.

A modified two-step seeded polymerization was used for the preparation of porous mono-sized microspheres of poly(ethylene glycol dimethacrylate-co-1-vinylimidazole) [poly(EGDMA-co-VIM)] of 7 mu m in size. The specific surface area and the EGDMA/VIM molar ratio of the microspheres were determined as 64.5 m(2)/g and 1.5:1.0 mol/mol, respectively. The adsorption of Pb(II) ions from aqueous solution onto the porous mono-sized poly(EGDMA-co-VIM) microspheres was examined. The maximum adsorption capacities of the microspheres towards Pb(II) ions were determined as 21.74, 30.52, 49.23 and 56.48 mg/g at 293 K, 303 K, 318 K and 338 K, respectively. The dynamic and equilibrium adsorption behaviours of the system were adequately described by the pseudo-second-order kinetic model and the Langmuir isotherm, respectively. The apparent activation energy was determined as 6.212 kJ/mol, which is characteristic of a chemically controlled reaction. The values of E-fe obtained from the Dubinin-Radushkevich equation in the non-linear form were 9.153 kJ/mol at 293 K, 10.34 kJ/mol at 303 K, 10.18 kJ/mol at 318 K and 10.91 kJ/mol at 333 K, thereby indicating that the adsorption of Pb(II) ions onto the porous mono-sized poly(EGDMA-co-VIM) microspheres occurred via a chemical process at all the temperatures studied. Various thermodynamic parameters, such as the Gibbs' free energy change (Delta G(0)), the standard enthalpy change (Delta H-0) and the standard entropy change (Delta S-0) were also determined. The thermodynamic parameters obtained indicated that the adsorption process was endothermic in nature. These results demonstrate that the material studied could be used as a purifier for the removal of Pb(II) ions from water and wastewater.

Poly(ethylene glycol dimethacrylate-1-vinyl-1,2,4-triazole) [poly(EGDMA-VTAZ)] beads (average diameter = 150–200 μm) were prepared by copolymerizing ethylene glycol dimethacrylate (EGDMA) with 1-vinyl-1,2,4-triazole (VTAZ). Poly(EGDMA-VTAZ) beads were characterized by swelling studies and scanning electron microscope (SEM). The adsorption of Cr(VI) from solutions was carried at different contact times, Cr(VI) concentrations, pH, and temperatures. High adsorption rates were achieved in about 240 min. The amount of Cr(VI) adsorbed increased with increasing concentration and decreasing pH and temperature. The intraparticle diffusion rate constants at various temperatures were calculated. Adsorption isotherms of Cr(VI) onto poly(EGDMA-VTAZ) have been determined and correlated with common isotherm equations such as Langmuir and Freundlich isotherm models. The Langmuir isotherm model appeared to fit the isotherm data better than the Freundlich isotherm model. The pseudo first-order kinetic model was used to describe the kinetic data. The study of temperature effect was quantified by calculating various thermodynamic parameters such as Gibbs free energy, enthalpy, and entropy changes. The dimensionless separation factor (RL) showed that the adsorption of metal ions onto poly(EGDMA-VTAZ) was favorable. It was seen that values of distribution coefficient (KD) decreasing with Cr(VI) concentration in solution at equilibrium (Ce) indicated that the occupation of activate surface sites of adsorbent increased with Cr(VI). © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009

The aim of this study is to prepare magnetic beads which can be used for the removal of heavy metal ions from synthetic solutions. Magnetic poly(ethylene glycol dimethacrylate-vinyl imidazole) [m-poly(EGDMA-VIM)] beads were produced by suspension polymerization in the presence of magnetite Fe3O4 nano-powder. The specific surface area of the m-poly(EGDMA-VIM) beads was found to be 63.1 m(2)/g with a size range of 150-200 m in diameter and the swelling ratio was 85%. The average Fe3O4 content of the resulting m-poly(EGDMA-VIM) beads was 12.4%. The maximum binding capacities of the m-poly(EGDMA-VIM) beads were 32.4 mg/g for Cu2+, 45.8mg/g for Zn2+, 84.2 mg/g for Cd2+ and 134.5 mg/g for Pb2+. The affinity order on mass basis is Pb2+ > Cd2+ > Zn2+ > Cu2+. Equilibrium data agreed well with the Langmuir model. pH significantly affected the binding capacity of the magnetic beads. Binding of heavy metal ions from synthetic wastewater was also studied. The binding capacities were 26.2 mg/g for Cu2+, 33.7 mg/g for Zn2+, 54.7 mg/g for Cd2+ and 108.4 mg/g for Pb2+. The magnetic beads could be regenerated up to about 97% by treating with 0.1 M HNO3. These features make m-poly(EGDMA-VIM) beads a potential candidate for support of heavy metal removal under magnetic field.

Magnetic vinylphenyl boronic acid microparticles, poly(ethylene glycol dimethacrylate(EG)-vinylphenyl boronic acid(VPBA)) [m-poly(EG-VPBA)], produced by suspension polymerization and characterized, was found to be an efficient solid polymer for Cr(VI) adsorption. The m-poly(EG-VPBA) microparticles were prepared by copolymerizing of ethylene glycol dimethylacrylate (EG) with 4-vinyl phenyl boronic acid (VPBA). The m-poly(EG-VPBA) microparticles were characterized by N-2 adsorption/desorption isotherms, electron spin resonance (ESR), X-ray diffraction (XRD), fourier transform infrared spectroscopy (FTIR), thermal gravimetric analysis (TGA), elemental analysis, scanning electron microscope (SEM) and swelling studies. The m-poly(EG-VPBA) microparticles were used at adsorbent/Cr(VI) ion ratios. The influence of pH, Cr(VI) initial concentration, temperature of the removal process was investigated. The maximum removal of Cr(VI) was observed at pH 2. Langmuir isotherm and Dubinin-Radushkvich isotherm were found to better fit the experiment data rather than Fruendlich isotherm. The kinetics of the adsorption process of Cr(VI) on the m-poly(EG-VPBA) microparticles were investigated using the pseudo first-order, pseudo-second-order, Ritch-second-order and intraparticle diffusion models, results showed that the pseudo-second order equation model provided the best correlation with the experimental results. The thermodynamic parameters (free energy change, Delta G(0) enthalpy change, Delta H-0; and entropy change, Delta S-0) for the adsorption have been evaluated.

Adsorption, electrokinetic properties and the interactions between polymer and clay minerals have recently received much attention, owing to the physicochemical properties of these materials. In this study, surface properties of poly(vinylimidazole)-adsorbed expanded perlite such as adsorption, adsorption kinetics and electrokinetic properties have been investigated as a function of temperature, ionic strength and pH. The zeta potential measurements have been performed to determine the isoelectric point (iep) and potential determining ions (pdi). Although pH strongly altered the zeta potential of expanded perlite sample, expanded perlite does not yield any isoelectric point in the pH ranges of 2–11, poly(vinylimidazole) (PVI) changes the interface charge from negative to positive for expanded perlite when adsorbed on its surface. Adsorbed amounts ( q e ) showed a great dependence on pH. The adsorption of PVI increases with increasing pH, ionic strength and temperature. The pH values where the maximum adsorbed mass occurred might be considered as the conditions where electrostatic attraction is the most favourable. Experimental adsorption data were investigated using Langmuir and Freundlich isotherm models and found that Langmuir isotherm model gave the best representation of the adsorption equilibrium. In order to investigate the mechanism of adsorption and potential rate controlling step, pseudo-first- and second-order kinetic equations, and intraparticle diffusion model have been used to test the experimental data. The rate constants and the related correlation coefficients were determined in order to assess which model provides the best-fit predicted data with experimental results. Pseudo-first-order kinetic equation provided the best fit to experimental data.

Poly(ethylene glycol dimethacrylate- n -vinyl imidazole) [poly(EGDMA-VIM)] hydrogel (average diameter 150–200 μm) was prepared by copolymerizing ethylene glycol dimethacrylate (EGDMA) with n -vinyl imidazole (VIM). The copolymer hydrogel bead composition was characterized by elemental analysis and found to contain 5 EGDMA monomer units each VIM monomer unit. Poly(EGDMA-VIM) beads had a specific surface area of 59.8 m 2 /g. Poly(EGDMA-VIM) beads were characterized by swelling studies and SEM. Cu 2+ ions were chelated on the poly(EGDMA-VIM) beads, then these beads were used in the adsorption of α-amylase from Aspergillus Oryzae in batch system. The maximum α-amylase adsorption capacity of the poly(EGDMA-VIM)–Cu 2+ beads was observed as 38.9 mg/g at pH 4.0. The K m values for immobilized α-amylase (poly(EGDMA-VIM)–Cu 2+ ) (22.5 mM) was higher than that of free enzyme (15.8 mM). Storage stability was found to increase with immobilization. It was observed that enzyme could be repeatedly adsorbed and desorbed without significant loss in adsorption capacity or enzyme activity.

One of the major causes of soil degradation throughout the world is water erosion. Anionic polyacrylamide (PAM) application to soils is an effective soil conservation practice for reducing runoff and soil losses caused by erosion. It also increases the infiltration rate of soils. The objective of this study was conducted to determine effects of different application rates of PAM (0 (control), 1.667, 3.333 and 5.000 kg.ha -1 ) on infiltration rate, runoff and soil losses. Polyacrylamide was sprayed on the surface of the experimental soils with different textures. The PAM treated soils were introduced to simulated rainfall at 61 mm/h intensity for an hour. The results indicated that, PAM applications significantly reduced surface runoff and soil losses, but increased infiltration rates. The effectiveness of PAM was higher in clay and clay loam soils than that of sandy clay loam soil. The most effective applications rates of PAM on reducing surface runoff and soil losses and increasing infiltration rates were found to be 3.333 and 5.000 kg.ha -1 . By considering the price and application cost of PAM, It was suggested that 3.333 kg.ha -1 PAM is the most suitable application rate. As compared with the control, it was obtained that PAM application with a rate of 3.333 kg.ha -1 reduced surface runoff and soil losses by 23.1 and 18.5%, respectively and increased infiltration rate by 24%. Key words : Polyacrylamide (PAM), soil erosion, soil loss, runoff, infiltration rate, simulated rainfall.

Ağır metallerin giderilmesi amacıyla manyetik poli(etilenglikoldimetakrilat-n-vinil-2-pirolidon) [m-poli(EG-VPO)] mikroküreleri Fe3O4 nanopartikül varlığında süspansiyon polimerizasyonu yöntemiyle sentezlendi. m-poli(EG-VPO) mikroküreleri elementel analiz, N2 adsorpsiyon-desorpsiyon izoterm testi, şişme testi, taramalı elektron mikroskobu (SEM) ve manyetizma ölçümleri ile karakterize edildi. m-poli(EG-VPO) mikrokürelerinin spesifik yüzey alanı 140,7 m2/g, şişme oranı, %40.19, sıfırlayıcı alan, Hc=0,0118 T, elementel analiz sonuçlarında azot oranı %N = 3.77 olarak belirlendi. Bu durum, m-poli(EG-VPO) mikrokürelerinin yumuşak manyetik malzeme olduğunu ve n-vinil-2-pirolidon ligantının polimerik yapıya girdiğini göstermektedir.Elde edilen mikrokürelerin ağır metal iyonları uzaklaştırılmasında kullanılabilirliğini araştırmak amacıyla Hg(II), Cu(II) ve Cr(VI) iyonları incelendi. Mikrokürelerin adsorpsiyon kapasitesi üzerinde etkili parametrelerden pH, başlangıç ağır metal iyonu derişimi, sıcaklık, zaman etkisi incelendi. Maksimum uzaklaştırma Cr(VI) iyonları için pH 2,0?de; Cu(II) iyonları için pH 5,0?te; Hg(II) iyonları için pH 6,5?te gözlendi. Sıcaklığın adsorpsiyona etkisi incelenmesi sonucunda, sıcaklığın 4oC?den 65oC?ye çıkarılmasıyla ağır metal iyonları adsorpsiyonunun arttığı gözlendi.m-poli(EG-VPO) mikrokürelerinin maksimum adsorpsiyon kapasitesi Hg(II), Cu(II) ve Cr(VI) iyonları için sırasıyla 400,0 mg/g, 270,3 mg/g ve 109,9 mg/g olarak belirlendi. Bu durum sulu çözeltilerden ağır metal iyonlarını uzaklaştırılmasında m-poli(EG-VPO) mikrokürelerinin etkili olduğunu göstermektedir. Kütle bazında ilgi sırası Cu(II) > Cr(VI) > Hg(II) şeklindedir. Adsorpsiyon kinetikleri incelenerek mevcut sistem için 4, 25, 45 ve 65oC?de Langmuir ve Freundlich adsorpsiyon izotermlerine uygulanabilirlik test edildi ve Langmuir modeline uygun bulundu. Ayrıca yalancı 1. derece, yalancı 2. derece ve partikül içi difüzyon modelleri de adsorpsiyon kinetiğinin incelenmesinde kullanıldı. Gibbs serbest enerji, entalpi ve entropi değişimi gibi termodinamik parametreler hesaplanarak sıcaklık etkisi belirlenmesi sonucunda adsorpsiyon sürecinin endotermik olduğu ve kendiliğinden gerçekleştiği belirlendi.Anahtar Kelimeler: Adsorpsiyon, ağır metal iyonları, manyetik polimerler, etilenglikoldimetakrilat, n-vinil-2-pirolidon Magnetic poly(ethyleneglycoldimethacrylate-n-vinyl-2-pyrrolidone) [m-poly(EG-VPO)] microbeads were synthesized by suspension polymerization technique in the presence of magnetite Fe3O4 nano-powder with the aim of heavy metal removal. M-poly(EG-VPO) microbeads were characterized by elemental analysis, N2 adsorption-desorption isotherm tests, swelling studies, scanning electron microscope (SEM) and magnetism measurements. The specific surface area of the m-poly(EG-VPO) beads was found to be 140,7 m2/g and the swelling ratio was 40,19%, coercive field was 0,00118, nitrogen ratio was %3,77. It was determined that m-poly(EG-VPO) microbeads were soft magnetic materials and the ligand N-vinyl-2-pyrrolidone was inserted into the polymer structure. In order to investigate usability of m-poly(EG-VPO) microbeads for heavy metal removal, Hg(II), Cu(II) and Cr(VI) ions were studied . Effects of pH, initial heavy metal ions concentration, temperature, contact time were investigated as the effective parameters on the adsorption capacities of the microspheres. Maximum uptake was obtained for Cr(VI) ions at pH 2,0; Cu(II) ions at pH 5,0; Hg(II) ions at pH 6,0. The result of the effect of temperature on the adsorption was that the adsorption of heavy metal ions was increased with the rise in temperature from 4 to 65oC. The maximum adsorption capacities of the m-poly(EG-VPO) beads for Hg(II), Cu(II), Cr(VI) were found 400,0 mg/g, 270,3 mg/g, 45,01 mg/g and109,9 mg/g respectively. In other words m-poly(EG-VPO) beads are efficient to remove heavy metal ions from aqueous solutions. The affinity order on mass basis is Cu(II) > Cr(VI) > Hg(II). Adsorption kinetics have been tested and the applicability of the Langmuir and Freudlich adsorption isotherms for the present system have been tested at 4, 25, 45 and 65oC and the Langmuir model was adequate. Also pseudo-first-order, pseudo-second-order and intraparticle diffusion models were used to describe the adsorption kinetics. In consequence of the study of temperature effect was quantified by calculating various thermodynamic parameters such as Gibbs free energy, enthalpy and entropy changes, adsorption process was endothermic in nature and spontaneous.Key Words: Adsorption, heavy metal ions, magnetic polymers, ethyleneglycoldimethacrylate, n-vinyl-2-pyrrolidone 103

The magnetic-poly(divinylbenzene-1-vinylimidazole) [m-poly(DVB-VIM)] microbeads (average diameter 53-212 mu m) were synthesized and characterized; their use as adsorbent in removal of Cr(VI) ions from aqueous solutions was investigated. The m-poly(DVB-VIM) microbeads were prepared by copolymerizing of divinylbenzene (DVB) with 1-vinylimidazole (VIM). The m-poly(DVB-VIM) microbeads were characterized by N-2 adsorption/desorption isotherms, ESR, elemental analysis, scanning electron microscope (SEM) and swelling studies. At fixed solid/solution ratio the various factors affecting adsorption of Cr(VI) ions from aqueous solutions such as pH, initial concentration, contact time and temperature were analyzed. Langmuir, Freundlich and Dubinin-Radushkvich isotherms were used as the model adsorption equilibrium data. Langmuir isotherm model was the most adequate. The pseudo-first-order, pseudo-second-order, Ritch-second-order and intraparticle diffusion models were used to describe the adsorption kinetics. The apparent activation energy was found to be 5.024 kJ mol(-1), which is characteristic of a chemically controlled reaction. The experimental data fitted to pseudo-second-order kinetic. The study of temperature effect was quantified by calculating various thermodynamic parameters such as Gibbs free energy, enthalpy and entropy changes. The thermodynamic parameters obtained indicated the endothermic nature of adsorption of Cr(VI) ions. Morever, after the use in adsorption, the m-poly(DVB-VIM) microbeads with paramagnetic property were separeted via the applied magnetic force. The magnetic beads could be desorbed up to about 97% by treating with 1.0 M NaOH. These features make the m-poly(DVB-VIM) microbeads a potential candidate for support of Cr(VI) ions removal under magnetic field.

Sulfonic acid functionalized poly(ethylene glycol dimethacrylate-1-vinyl-1,2,4-triazole), poly(EGDMA-VTAZ-SO 3 H), is evaluated in the esterification of lactic acid with methanol. From nitrogen physisorption data, high surface area (220 m 2 /g) and type IV isotherm are obtained. Conversion measurements indicate a stronger interaction of poly(EGDMA-VTAZ-20%SO 3 H) with water molecules than that occurring in poly(EGDMA-VTAZ-10%SO 3 H). Hence, the higher catalytic activity of poly(EGDMA-VTAZ-10%SO 3 H) is related to the more hydrophobic microenvironment of –SO 3 H sites, which reduces the acid site deactivation associated with adsorption of water generated during the reaction. Moreover, apparent activation energy is found to be 48.02 kJ mol −1 , which can be comparable with the literature values.

Köçkar, Hakan (Balikesir Author), In this paper we report the electrical characteristics of the Schottky diodes formed by surface polymerization of the Poly(ethylene glycol dimethanylate-n-vinyl imidazole)/Single Walled Carbon Nanotubes on n-Si The Single Walled Carbon Nanotubes were synthesized by CVD method. The main electrical properties of the Poly(ethylene glycol dimethanylate-n-vinyl imidazole)/Single Walled Carbon Nanotubes/n-Si have been investigated through the barrier heights, the ideality factors and the impurity density distribution, by using current-voltage and reverse bias capacitance voltage characteristics. Electrical measurements were carried out at room temperature. Poly(ethylene glycol dimethacrylate-n-vinyl imidazole)/Single Walled Carbon Nanotubes/n-Si Schottky diode current-voltage characteristics display low reverse-bias leakage currents and average barrier heights of 0.61 +/- 0.02 eV and 0.72 +/- 0.02 eV obtained from both current-voltage and capacitance-voltage measurements at room temperature, respectively.

Designing an immobilised metal ion affinity process on large-scale demands that a thorough understanding be developed regarding the adsorption behaviour of proteins on metal-loaded gels and the characteristic adsorption parameters to be evaluated. In view of this requirement, interaction of alpha-amylase as a model protein with newly synthesised magnetic-poly(divinylbenzene-1-vinylimidazole) [m-poly(DVB-VIM)] microbeads (average diameter, 53-212 mu m) was investigated. The m-poly(DVB-VIM) microbeads were prepared by copolymerising of divinylbenzene (DVB) with 1-vinylimidazole (VIM). The m-poly(DVB-VIM) microbeads were characterised by N-2 adsorption/desorption isotherms, electron spin resonance, elemental analysis, scanning electron microscope and swelling studies. Cu2+ ions were chelated on the m-poly(DVB-VIM) beads and used in adsorption of alpha-amylase in a batch system. The maximum alpha-amylase adsorption capacity of the m-poly(DVB-VIM)-Cu2+ beads was determined as 10.84 mg/g at pH 6.0, 25 A degrees C. The adsorption data were analyzed using three isotherm models, which are the Langmuir, Freundlich and Dubinin-Radushkevich isotherm models. The pseudo-first-order, pseudo-second-order, modified Ritchie's-second-order and intraparticle diffusion models were used to test dynamic experimental data. The study of temperature effect was quantified by calculating various thermodynamic parameters such as Gibbs free energy, enthalpy and entropy changes.

The barium hexaferrite (BaFe 12 O 19 ) containing magnetic poly(ethylene glycol dimethacrylate–vinyl pyridine), (mag-poly(EGDMA–VP)) beads (average diameter = 53–212 μm) were synthesized and characterized. Their use as an adsorbent in the removal of diethyl phthalate (DEP) from an aqueous solution was investigated. The mag-poly(EGDMA–VP) beads were prepared by copolymerizing of 4-vinyl pyridine (VP) with ethylene glycol dimethacrylate (EGDMA). The mag-poly(EGDMA–VP) beads were characterized by N 2 adsorption/desorption isotherms (BET), vibrating sample magnetometer (VSM), X-ray powder diffraction (XRD), elemental analysis, scanning electron microscope (SEM) and swelling studies. At a fixed solid/solution ratio, the various factors affecting the adsorption of DEP from aqueous solutions such as pH, initial concentration, contact time and temperature were analyzed. The maximum DEP adsorption capacity of the mag-poly(EGDMA–VP) beads was determined as 98.9 mg/g at pH 3.0, 25 °C. All the isotherm data can be fitted with both the Langmuir and the Dubinin-Radushkevich isotherm models. The pseudo first-order, pseudo-second-order, Ritch-second-order and intraparticle diffusion models were used to describe the adsorption kinetics. The thermodynamic parameters obtained indicated the exothermic nature of the adsorption. The DEP adsorption capacity did not change after 10 batch successive reactions, demonstrating the usefulness of the magnetic beads in applications.

Poly(ethylene glycol dimethacrylate–1-vinyl-1,2,4-triazole) [poly(EGDMA–VTAZ)] beads with an average diameter of 100–200 μm were obtained by the copolymerization of ethylene glycol dimethacrylate (EGDMA) with 1-vinyl-1,2,4-triazole (VTAZ). The copolymer hydrogel bead composition was determined by elemental analysis and was found to contain 5 EGDMA monomer units for each VTAZ monomer unit. The poly(EGDMA–VTAZ) beads were characterized by swelling studies and scanning electron microscopy (SEM). The specific surface area of the poly(EGDMA–VTAZ) beads was found 65.8 m2/g. Cu2+ ions were chelated on the poly(EGDMA–VTAZ) beads. The Cu2+ loading was 82.6 μmol/g of support. Cu2+-chelated poly(EGDMA–VTAZ) beads with a swelling ratio of 84% were used in the immobilization of Aspergillus niger glucoamylase in a batch system. The maximum glucoamylase adsorption capacity of the poly(EGDMA–VTAZ)–Cu2+ beads was 104 mg/g at pH 6.5. The adsorption isotherm of the poly(EGDMA–VTAZ)–Cu2+ beads fitted well with the Langmuir model. Adsorption kinetics data were tested with pseudo-first- and second-order models. The kinetic studies showed that the adsorption followed a pseudo-second-order reaction model. The Michaelis constant value for the immobilized glucoamylase (1.15 mg/mL) was higher than that for free glucoamylase (1.00 mg/mL). The maximum initial rate of the reaction values were 42.9 U/mg for the free enzyme and 33.3 U/mg for the immobilized enzyme. The optimum temperature for the immobilized preparation of poly(EGDMA–VTAZ)–Cu2+–glucoamylase was 65°C; this was 5°C higher than that of the free enzyme at 60°C. The glucoamylase adsorption capacity and adsorbed enzyme activity slightly decreased after 10 batch successive reactions; this demonstrated the usefulness of the enzyme-loaded beads in biocatalytic applications. The storage stability was found to increase with immobilization. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011

Graphical abstract Electric chatacterization of organic field effect transistors with PVT dielectric layer: Pentacene is used as active layer in p-channel device; Fullerene is the active layer in n-channel device. Channel length is 2mm, channel width is 0.06mm. Research highlights ► PVT shows low leakage current and high breakdown voltage. ► Both n-channel and p-channel OFET devices give low threshold voltage and are lack of hysteresis. ► Excellent film formation property of PVT allows for fabricating low voltage operation OFET devices. ► All solution processed polymer ambipolar OFET device is realized via layer by layer coating., Water soluble poly(1-vinyl-1,2,4-triazole) (PVT) as a novel dielectric layer for organic field effect transistor is studied. Dielectric spectroscopy characterization reveals it has low leakage current and rather high breakdown voltage. Both n-channel and p-channel organic field effect transistors are fabricated using pentacene and fullerene as active layers. Both devices show device performances with lack of hysteresis, very low threshold voltages and high on/off ratios. Excellent film formation property is utilized to make AlOx and thin PVT bilayer in order to decrease the operating voltage of the devices. All solution processed ambipolar device is fabricated with simple spin coating steps using poly(2-methoxy-5-(2-ethyl-hexyloxy)-1,4-phenylenevinylene) (MEH–PPV) end capped with polyhedral oligomeric silsesquioxanes (POSS) as active layer. Our investigations show that PVT can be a very promising dielectric for organic field effect transistors.

Sulfonic acid functionalized poly (ethylene glycol dimethacrylate-1-vinyl-1,2,4-triazole), poly (EGDMA–VTAZ–SO3H) (average diameter 1.0–1.5 mm), was found to be efficient solid acid catalyst for the esterification of methanol and propionic acid under heterogeneous reaction conditions. The pristine polymer, poly (EGDMA–VTAZ), was produced by suspension polymerization and then proton-conducting polymer was obtained by blending of poly (EGDMA–VTAZ) with different percentage of H2SO4 solutions. The protonation of aromatic heterocyclic rings was proved with Fourier-transform infrared spectroscopy (FT-IR). Thermo gravimetric (TG) analysis showed that the catalyst is thermally stable up to 573 K. The surface morphology of the catalyst was characterized by scanning electron microscopy (SEM). Poly (EGDMA–VTAZ–SO3H) beads can be regenerated and reused, so this provides a potential application. It has a rate constant which exceeds that of Amberlyst-15 by a factor of about four at 333 K. As for the reaction equilibrium constant (Ke), which is independent of temperature ranging from 318 to 343 K, was determined to be 3.16. The apparent activation energy was found to be 41.6 kJ mol−1 for poly (EGDMA–VTAZ–SO3H).

Sunulan çalışmada; manyetik poli(divinil benzen-N-vinil imidazol) [m-poli(DVB-VIM)] mikroküreleri Fe3O4 nanopartikül varlığında süspansiyon polimerizasyonu yöntemiyle sentezlenerek ağır metal iyonlarının uzaklaştırılmasında kullanıldı. m-poli(DVB-VIM) mikroküreleri elementel analiz, N2 adsorpsiyon-desorpsiyon izoterm testi, şişme testi, yoğunluk ölçümleri, taramalı elektron mikroskobu (SEM) ve manyetizma ölçümleri ile karakterize edildi. m-poli(DVB-VIM) mikrokürelerinin spesifik yüzey alanı 29.47 m2/g, boyut dağılımı 53-212 µm, şişme oranı %44 ve ortalama Fe3O4 içeriği %10,2 olarak belirlendi. Mikrokürelerin yapısındaki VIM miktarı 3,021 mmol/g polimer olarak bulundu. Bu durum m-poli(DVB-VIM) mikrokürelerinin manyetik olduğunu ve N-vinil imidazol ligantının polimerik yapıya girdiğini göstermektedir.Elde edilen mikrokürelerin ağır metal iyonları uzaklaştırılmasında kullanılabilirliğini araştırmak için; Cr(VI), Ni(II), Zn(II), Pb(II) ve Cu(II) iyonları örnek iyon olarak kullanıldı. Mikrokürelerin adsorpsiyon kapasitesi üzerinde etkili parametrelerden pH, başlangıç ağır metal iyonu konsantrasyonu, sıcaklık, zaman ve adsorban miktarı etkisi incelendi. Maksimum uzaklaştırma Cr(VI) iyonları için pH 2,0'de; Cu(II) iyonları için pH 5,0'te; Zn(II), Ni(II) ve Pb(II) iyonları için pH 6,0'da gözlendi. Sıcaklığın adsorpsiyona etkisi incelendi ve sıcaklığın 4oC'den 65oC'ye çıkarılmasıyla ağır metal iyonları adsorpsiyonunun arttığı gözlendi.m-poli(DVB-VIM) mikrokürelerinin 100 ppm konsantrasyonda ve 65oC'deki adsorpsiyon kapasitesi Cu(II), Cr(VI), Pb(II), Ni(II) ve Zn(II) iyonları için sırasıyla 52,90 mg/g, 46,85 mg/g, 45,01 mg/g, 23,07 mg/g ve 22,39 mg/g olarak belirlendi. Bu durum sulu çözeltilerden ağır metal iyonlarını uzaklaştırılmasında m-poli(DVB-VIM) mikrokürelerinin etkili olduğunu göstermektedir. Kütle bazında ilgi sırası Cu(II) > Cr(VI) > Pb(II) > Ni(II) > Zn(II) şeklindedir. Adsorpsiyon kinetikleri incelenerek mevcut sistem için 4, 25, 45 ve 65oC'de Langmuir ve Freundlich adsorpsiyon izotermlerine uygulanabilirlik test edildi. Denge verileri Langmuir modeline uygun bulundu. Ayrıca yalancı (pseudo) 1. derece, yalancı (pseudo) 2. derece ve partikül içi difüzyon modelleri de adsorpsiyon kinetiğinin incelenmesinde kullanıldı. Gibbs serbest enerji, entalpi ve entropi değişimi gibi termodinamik parametreler hesaplanarak sıcaklık etkisi belirlendi. Bu çalışmada adsorpsiyon sürecinin endotermik olduğu ve kendiliğinden gerçekleştiği belirlendi. Manyetik mikrokürelerin rejenerasyonu Cu(II), Pb(II), Ni(II) ve Zn(II) için 0,1 M HNO3; Cr(VI) için 1 M NaOH kullanılarak gerçekleştirildi. Aynı manyetik mikroküreler kullanılarak adsorpsiyon-desorpsiyon döngüsü 10 kez tekrarlandı ve ağır metal iyon kapasitesinde önemli bir değişim gözlenmedi. In present study, magnetic poly(divinyl benzene-N-vinyl imidazole) [m-poly(DVB-VIM)] microbeads were synthesized by suspension polymerization technique in the presence of magnetite Fe3O4 nano-powder and used for heavy metal ions removal studies. m-poly(DVB-VIM) microbeads were characterized by elemental analysis, N2 adsorption-desorption isotherm tests, swelling studies, density measurements, scanning electron microscope (SEM) and magnetism measurements. The specific surface area of the m-poly(DVB-VIM) beads was found to be 29.47 m2/g with a size range of 53-212 µm in diameter and the swelling ratio was 44%. The average Fe3O4 content of the resulting m-poly(DVB-VIM) microbeads was 10,2%. The incorporation of the VIM was found 3,021 mmol/g polymer. It was determined that m-poly(DVB-VIM) microbeads are magnetic and the ligand N-vinyl imidazole was inserted into the polymer structure.Cr(VI), Ni(II), Zn(II), Pb(II) and Cu(II) ions were used as model species to investigate the usability of the obtained microspheres in heavy metal removal. Effects of pH, initial heavy metal ions concentration, temperature, contact time and adsorbent dosage were investigated as the effective parameters on the adsorption capacities of the microspheres. Maximum uptake was obtained for Cr(VI) ions at pH 2,0; Cu(II) ions at pH 5,0; Zn(II), Ni(II) and Pb(II) ions at pH 6,0. The effect of temperature on the adsorption was studied and the adsorption of heavy metal ions was increased with the rise in temperature from 4 to 65oC.The adsorption capacities of the m-poly(DVB-VIM) beads for Cu(II), Cr(VI), Pb(II), Ni(II) and Zn(II) were found 52,90 mg/g, 46,85 mg/g, 45,01 mg/g, 23,07 mg/g and 22,39 mg/g, respectively at 100 ppm and 65oC. In other words m-poly(DVB-VIM) beads were found to efficiently remove heavy metal ions from aqueous solutions. The affinity order on mass basis is Cu(II) > Cr(VI) > Pb(II) > Ni(II) > Zn(II). Adsorption kinetics have been tested and the applicability of the Langmuir and Freudlich adsorption isotherms for the present system have been tested at 4, 25, 45 and 65oC. Equilibrium data agreed well with the Langmuir model. Also pseudo-first-order, pseudo-second order and intraparticle diffusion models were used to describe the adsorption kinetics. The study of temperature effect was quantified by calculating various thermodynamic parameters such as Gibbs free energy, enthalpy and entropy changes. In this study, adsorption process was endothermic in nature and spontaneous. Regeneration of the magnetic microbeads was easily performed with 0,1 M HNO3 for Cu(II), Pb(II), Ni(II) and Zn(II); 1 M NaOH for Cr(VI). Adsorption-desorption cycles were be performed ten-times by using same magnetic microbeads and any noticeable loss was not determined. 138

The aim of this study was to prepare magnetic beads that could be used for the removal of heavy-metal ions from synthetic solutions. Magnetic poly(ethylene glycol dimethacrylate-1-vinyl-1,2,4-triazole) [m-poly (EGDMA-VTAZ)] beads were produced by suspension polymerization in the presence of a magnetite Fe3O4 nanopowder. The specific surface area of the m-poly(EGDMAVTAZ) beads was 74.8 m(2)/g with a diameter range of 150-200 mu m, and the swelling ratio was 84%. The average Fe3O4 content of the resulting m-poly(EGDMA-VTAZ) beads was 14.8%. The maximum binding capacities of the m-poly (EGDMA-VTAZ) beads from aquous solution were 284.3 mg/g for Hg2+, 193.8 mg/g for Pb2+, 151.5 mg/g for Cu2+, 128.1 mg/g for Cd2+, and 99.4 mg/g for Zn2+. The affinity order on a mass basis was Hg2+ > Pb2+ > Cu2+ > Cd2+> Zn2+. The binding capacities from synthetic waste water were 178.1 mg/g for Hg2+, 132.4 mg/g for Pb2+, 83.5 mg/g for Cu2+, 54.1 mg/g for Cd2+, and 32.4 mg/g for Zn2+. The magnetic beads could be regenerated (up to ca. 97%) by a treatment with 0.1 M HNO3. These features make m-poly(EGDMA-VTAZ) beads potential supports for heavy-metal removal under a magnetic field. (C) 2009 Wiley Periodicals, Inc. J Appl Polym Sci 114: 2246-2253, 2009

We prepared poly(ethylene glycol dimethacrylate–1-vinyl-1,2,4-triazole) [poly(EGDMA–VTAZ)] beads (average diameter = 150–200 μm) by copolymerizing ethylene glycol dimethacrylate (EGDMA) with 1-vinyl-1,2,4-triazole (VTAZ). The copolymer composition was characterized by elemental analysis and found to contain five EGDMA monomer units for each VTAZ monomer unit. The poly(EGDMA–VTAZ) beads had a specific surface area of 65.8 m2/g. Poly(EGDMA–VTAZ) beads were characterized by Fourier transform infrared spectroscopy, elemental analysis, surface area measurements, swelling studies, and scanning electron microscopy. Poly(EGDMA–VTAZ) beads with a swelling ratio of 84% were used for the heavy-metal removal studies. The adsorption capacities of the beads for Cd(II), Hg(II), and Pb(II) were investigated in aqueous media containing different amounts of these ions (5–750 mg/L) and at different pH values (3.0–7.0). The maximum adsorption capacities of the poly(EGDMA–VTAZ) beads were 85.7 mg/g (0.76 mmol/g) for Cd(II), 134.9 mg/g (0.65 mmol/g) for Pb(II), and 186.5 mg/g (0.93 mmol/g) for Hg(II). The affinity order toward triazole groups on a molar basis was observed as follows: Hg(II) > Cd(II) > Pb(II). pH significantly affected the adsorption capacity of the VTAZ-incorporated beads. The equilibrium data were well fitted to the Redlich–Peterson isotherm. Consideration of the kinetic data suggested that chemisorption processes could have been the rate-limiting step in the adsorption process. Regeneration of the chelating-beads was easily performed with 0.1M HNO3. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 4276–4283, 2006

We investigated a new adsorbent system, Reactive Red 120 attached poly(2-hydroxyethyl methacrylate ethylene dimethacrylate) [poly(HEMA–EDMA)] beads, for the removal of Ni2+ ions from aqueous solutions. Poly(HEMA–EDMA) beads were prepared by the modified suspension copolymerization of 2-hydroxyethyl methacrylate and ethylene dimethacrylate. Reactive Red 120 molecules were covalently attached to the beads. The beads (150–250 μm), having a swelling ratio of 55% and carrying 25.5 μmol of Reactive Red 120/g of polymer, were used in the removal of Ni2+ ions. The adsorption rate and capacity of the Reactive Red 120 attached poly(HEMA–EDMA) beads for Ni2+ ions was investigated in aqueous media containing different amounts of Ni2+ ions (5–35 mg/L) and having different pH values (2.0–7.0). Very high adsorption rates were observed at the beginning, and adsorption equilibria were then gradually achieved in about 60 min. The maximum adsorption of Ni2+ ions onto the Reactive Red 120 attached poly(HEMA–EDMA) beads was 2.83 mg/g at pH 6.0. The nonspecific adsorption of Ni2+ ions onto poly(HEMA–EDMA) beads was negligible (0.1 mg/g). The desorption of Ni2+ ions was studied with 0.1M HNO3. High desorption ratios (>90%) were achieved. The intraparticle diffusion rate constants at various temperatures were calculated as k20°C = 0.565 mg/g min0.5, k30°C = 0.560 mg/g min0.5, and k40°C = 0.385 mg/g min0.5. Adsorption–desorption cycles showed the feasibility of repeated use of this novel adsorbent system. The equilibrium data fitted very well both Langmuir and Freundlich adsorption models. The pseudo-first-order kinetic model was used to describe the kinetic data. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100:5056–5065, 2006

N-methacryloyl-(L)-alanine (MALA) was synthesized by using methacryloyl chloride and alanine as a metal-complexing ligand or comonomer. Spherical beads with an average diameter of 150–200 μm were obtained by suspension polymerization of MALA and 2-hydroxyethyl methacrylate (HEMA) conducted in an aqueous dispersion medium. Poly(HEMA–MALA) beads were characterized by SEM, swelling studies, surface area measurement, and elemental analysis. Poly(HEMA–MALA) beads have a specific surface area of 68.5 m2/g. Poly(HEMA–MALA) beads with a swelling ratio of 63%, and containing 247 μmol MALA/g were used in the removal of Hg2+ from aqueous solutions. Adsorption equilibrium was achieved in about 60 min. The adsorption of Hg2+ ions onto PHEMA beads was negligible (0.3 mg/g). The MALA incorporation into the polymer structure significantly increased the mercury adsorption capacity (168 mg/g). Adsorption capacity of MALA containing beads increased significantly with pH. The adsorption of Hg2+ ions increased with increasing pH and reached a plateau value at around pH 5.0. Competitive heavy metal adsorption from aqueous solutions containing Cd2+, Cu2+, Pb2+, and Hg2+ was also investigated. The adsorption capacities are 44.5 mg/g for Hg2+, 6.4 mg/g for Cd2+, 2.9 mg/g for Pb2+, and 2.0 mg/g for Cu2+ ions. These results may be considered as an indication of higher specificity of the poly(HEMA–MALA) beads for the Hg2+ comparing to other ions. Consecutive adsorption and elution operations showed the feasibility of repeated use for poly(HEMA–MALA) chelating beads. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 1222–1228, 2006

Poly(ethylene glycol dimethacrylate-n-vinyl imidazole) [poly(EGDMA-VIM)] hydrogel (average diameter 150-200 mu m) was prepared copolymerizing ethylene glycol dimethacrylate (EGDMA) with n-vinyl imidazole (VIM). Poly(EGDMA-VIM) beads had a specific surface area of 59.8 M-2/g. Poly(EGDMA-VIM) beads were characterized by swelling studies and scanning electron microscope (SEM). Cu2+ ions were chelated on the poly(EGDMA-VIM) beads (452 mu mol Cu2+/g), then the metal-chelated beads were used in the adsorption of yeast invertase in a batch system. The maximum invertase adsorption capacity of the poly(EGDMA-VIM)-Cu2+ beads was observed as 35.2 mg/g at pH 4.5. The adsorption isotherm of the poly(EGDMA-VIM)-Cu2+ beads can be well fitted to the Langmuir model. Adsorption kinetics data were tested using pseudo-first- and -second-order models. Kinetic studies showed that the adsorption followed a pseudo- second-order reaction. The value of the Michaelis constant K-m of invertase was significantly larger upon adsorption, indicating decreased affinity by the enzyme for its substrate, whereas V-max was smaller for the adsorbed invertase. The optimum temperature for the adsorbed preparation of poly(EGDMA-VIM)-CU2+- invertase at 50 degrees C, 10 degrees C higher than that of the free enzyme at 40 degrees C. Storage stability was found to increase with adsorption. Adsorbed invertase retains an activity of 82% after 10 batch successive reactions, demonstrating the usefulness of the enzyme-loaded beads in biocatalytic applications.

The adsorption of polyvinylimidazole (PVI) onto kaolinite from aqueous solutions has been investigated systematically as a function of parameters such as calcination temperature of kaolinite, pH, ionic strength, and temperature. According to the experimental results, the adsorption of PVI increases with pH from 8.50 to 11.50, temperature from 25 to 55 degrees C, and ionic strength from 0 to 0.1 mol L(-1). The kaolinite sample calcined at 600 degrees C has a maximum adsorption capacity. Adsorption isotherms of PVI onto kaolinite have been determined and correlated with common isotherm equations such as Langmuir and Freundlich isotherm models. The Langmuir isotherm model appeared to fit the isotherm data better than the Freundlich isotherm model. The physical properties of this adsorbent are consistent with the parameters obtained from the isotherm equations. Furthermore, the zeta potentials of kaolinite suspensions have been measured in aqueous solutions of different PVI concentrations and pH. From the experimental results, (i) pH strongly alters the zeta potential of kaolinite; (ii) kaolinite has an isoelectric point at about pH 2.35 in water and about pH 8.75 in 249.9 ppm PVI concentration; (iii) PVI changes the interface charge from negative to positive for kaolinite. The study of temperature effect has been quantified by calculating various thermodynamic parameters such as Gibbs free energy, enthalpy, and entropy changes. The dimensionless separation factor (RL) has shown that kaolinite can be used for adsorption of PVI from aqueous solutions.

Reactive Green HE 4BD carrying polyamide hollow fibers were investigated as dye-affinity adsorbents for removal of chlorophenols (i.e., phenol. o-chlorophenol, p-chlorophenol and 2,4,6-trichlorophenol). Adsorption rates of chlorophenols were very high. Equilibrium was achieved in about 30 min. The applicability of two kinetic models including pseudo-first order and pseudo-second order model was estimated on the basis of comparative analysis of the corresponding rate parameters, equilibrium capacity and correlation coefficients. Results suggest that chemisorption process could be the rate-limiting step in the adsorption process. The maximum adsorption values of chlorophenols onto the Reactive Green HE 4BD carrying hollow fibers were 145.9 mu mol/g for phenol, 179.2 mu mol/g for 2,4,6-trichlorophenol, 194.5 mu mol/g for p-chlorophenol and 202.8 mu mol/g for o-chlorophenol. The affinity order was as follows: o-chlorophenol > p-chlorophenol > 2,4,6-trichlorophenol > phenol. The adsorption capacity of chlorophenols decreased with increasing pH. Desorption of chlorophenols was achieved using methanol solution (30%, v/v). The Reactive Green HE 4BD-carrying hollow fibers are suitable for repeated use for more than 10 cycles without noticeable loss of adsorption capacity. (c) 2006 Elsevier B.V. All rights reserved.

Poly(ethylene glycol dimethacrylate-n-vinyl imidazole) [poly(EGDMA-VIM)] hydrogel (average diameter 150-200 mum) was prepared by copolymerizing ethylene glycol dimethacrylate (EGDMA) with n-vinyl imidazole (VIM). The copolymer hydrogel bead composition was characterized by elemental analysis and found to contain 5 EGDMA monomer units each VIM monomer unit. Poly(EGDMA-VIM) beads had a specific surface area of 59.8 m(2)/g. Poly(EGDMA-VIM) beads were characterized by swelling studies and scanning electron microscopy (SEM). These poly(EGDMA-VIM) beads with a swelling ratio of 78% were used for the heavy metal removal studies. Chelation capacity of the beads for the selected metal ions, i.e., Cd(II), Hg(II) and Pb(II) were investigated in aqueous media containing different amounts of these ions (10-750 mg/l) and at different pH values (3.0-7.0). Chelation rate was very fast. The maximum chelation capacities of the poly(EGDMA-VIM) beads were 69.4 mg/g for Cd(H), 114.8 mg/g for Pb(II) and 163.5 mg/g for Hg(II). The affinity order on molar basis was observed as follows: Hg(H) > Cd(II) > Pb(II). Chelation behavior of heavy metal ions could be modelled using both the Langmuir and Freundlich isotherms. pH significantly affected the chelation capacity of VIM incorporated beads. Chelation of heavy metal ions from synthetic wastewater was also studied. The chelation capacities are 45.6 mg/g for U(II), 74.2 mg/g for Hg(H) and 92.5 mg/g for Pb(II) at 0.5 mmol/l initial metal concentration. Regeneration of the chelating-beads was easily performed with 0.1 M HNO3. These features make poly(EGDMA-VIM) beads potential candidate adsorbent for heavy metal removal: (C) 2003 Elsevier B.V. All rights reserved.