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The crystal structure of the new double CuII complex salt, [Cu(L)(H2O)2][Cu(L)]Br4·2H2O (L = 3,14-diethyl-2,6,13,17-tetraazatricyclo[16.4.0.07,12]docosane, C22H44N4) has been determined using synchrotron radiation. The asymmetric unit contains one half of a [Cu(L)(H2O)2]2+ cation, one half of a [Cu(L)]2+ cation (both completed by crystallographic inversion symmetry), two bromide anions and one water solvent molecule. The CuII atom in the first complex exists in a tetragonally distorted octahedral environment with the four N atoms of the macrocyclic ligand in equatorial and two aqua ligands in axial positions, whereas the CuII atom in the second complex exists in a square-planar environment defined by the four nitrogen atoms of the macrocyclic ligand. The two macrocyclic rings adopt the most stable trans-III configuration with normal Cu—N bond lengths from 2.016 (3) to 2.055 (3) Å and an axial Cu—O bond length of 2.658 (4) Å. The crystal structure is stabilized by intermolecular hydrogen bonds involving the macrocycle N—H or C—H groups and the O—H groups of water molecules as donor groups, and the O atoms of water molecules and bromide anions as acceptor groups, giving rise to a one-dimensional network extending parallel to [100].

Litter and compost were obtained at a cowshed of a livestock farm in Andong city in Korea. The morphological change of nitrogen and phosphorous from these samples were examined and suggested a more useful and realistic way for reducing them. Constituents and their content of sample were identified by XRF. The nitrite ion (NO2 −), nitrate ion (NO2 −) and phosphate ion (PO4 3−) and ammonium ion (NH4 +), total phosphorous (T-P) and total nitrogen (T-N) released from sample were analyzed using ion chromatograph and UV/Vis spectrometry. As the results of this study, the ammonia in the early stage of cow excretion is a need to make an ammonia gas state that can be immediately volatile by increasing the pH. Nitrogen and phosphorous, the main source of nutrition in green algal bloom can be reduced by transforming insoluble salts such as calcium phosphate (CaHPO4·3H2O) and struvite (NH4MgPO4·6H2O), respectively, with addition of Ca and Mg after stimulating fermentation of compost.

Single crystals of 3,14-dimethyl-2,6,13,17-tetraazoniatricyclo(16.4.0.07,12)docosane tetrachloride tetrahydrate compound, [C20H44N4]Cl4·4H2O (1), were obtained by a novel synthetic route and characterized by elemental analysis and X-ray diffraction. The synthesized compound crystallized in the monoclinic space group P21/n with two molecules of compound 1 in the unit cell [a = 7.5548(3) Å, b = 23.1838(8) Å, c = 8.3101(4) Å; β = 103.390(3)º]. The asymmetric unit contains half a centrosymmetric macrocyclic cation, two chloride anions and two water molecules. The organic [C20H44N4]4+ fragment of 1 adopts an exodentate [3,4,3,4]-D conformation. The C–C and N–C bond lengths of the macrocyclic tetracation range 1.525(3)-1.540(3) Å and 1.505(3)-1.519(3) Å, respectively. A three-dimensional hydrogen bonding network provides crystal cohesion through O–H···Cl, N–H···Cl and N–H···O interactions between organic cations, chloride anions and water molecules. The functional groups present in the crystal were studied by Fourier-transform infrared spectroscopy and Raman spectroscopy. The Hirshfeld surface analysis and 2D fingerprint plots revealed that the crystal packing in 1 is dominated by H···H, Cl···H/H···Cl and O···H/H···O contacts.

The crystal structure of 3,14-dimethyl-2,6,13,17-tetraazatricyclo(16.4.0.07,12)docosane-2-(nitric acid), C20H40N4·2(NO2OH) had been determined using synchrotron radiation at 220 K. The compound crystallized in the space group P21/n of the monoclinic system with two mononuclear formula units in a cell of dimensions a = 9.1930(18), b = 10.120(2), c = 12.979(3) Å and β = 101.06(3)º. The asymmetric unit contains half a centrosymmetric macrocycle and one nitric acid molecule. There were two molecules in the unit cell. In structure of macrocycle, C-C and N-C bond lengths were in the range 1.5198(19) to 1.5367(18) Å and 1.4744(16) to 1.4986 (16) Å, respectively. The NO2OH group has one longer N-O bond of 1.3441(18) Å and two shorter N-O bond of 1.2509(19) Å and 1.2510(19) Å, and O-N-O angles of 126.31(14)º, 117.98(14)º and 115.71(14)º. The N-H···O and N-H···N hydrogen bonds interconnect macrocycle (C20H40N4) with nitric acid molecules while two O-H···O hydrogen bonds link the nitric acid molecule to neighboring nitric acid molecule each other. The molecule was stabilized by forming intermolecular N-H···O, N-H−N and O-H···O hydrogen bonds. Hirshfeld surface analysis by 3D molecular surface contours and 2D fingerprint plots have been used to analyze intermolecular interactions present in the crystal.

In the title complex, [Cu(C22H44N4)(H2O)2][Cu(C22H44N4)]Br4·2H2O, each of the two complex cations lies about an inversion center. The two macrocyclic rings adopt the most stable trans-III configuration. In the crystal, O—H⋯Br, N—H⋯Br, N—H⋯O and C—H⋯O hydrogen bonds connect the complex cations, bromide anions, semi-coordinating H2O ligands and water solvent mol­ecules, forming a one-dimensional network extending parallel [100]., The crystal structure of the new double CuII complex salt, [Cu(L)(H2O)2][Cu(L)]Br4·2H2O (L = 3,14-diethyl-2,6,13,17-tetra­aza­tri­cyclo­[16.4.0.07,12]docosane, C22H44N4) has been determined using synchrotron radiation. The asymmetric unit contains one half of a [Cu(L)(H2O)2]2+ cation, one half of a [Cu(L)]2+ cation (both completed by crystallographic inversion symmetry), two bromide anions and one water solvent mol­ecule. The CuII atom in the first complex exists in a tetra­gonally distorted octa­hedral environment with the four N atoms of the macrocyclic ligand in equatorial and two aqua ligands in axial positions, whereas the CuII atom in the second complex exists in a square-planar environment defined by the four nitro­gen atoms of the macrocyclic ligand. The two macrocyclic rings adopt the most stable trans-III configuration with normal Cu—N bond lengths from 2.016 (3) to 2.055 (3) Å and an axial Cu—O bond length of 2.658 (4) Å. The crystal structure is stabilized by inter­molecular hydrogen bonds involving the macrocycle N—H or C—H groups and the O—H groups of water mol­ecules as donor groups, and the O atoms of water mol­ecules and bromide anions as acceptor groups, giving rise to a one-dimensional network extending parallel to [100].

In this study, adsorption of NO3- -N and PO43--P on granular activated charcoal (GAC) was investigated depending on pH, agitation time, GAC dosage, adsorption capacity and adsorption isotherms by employing batch adsorption type. The GAC was characterized by thermogravimetric analysis (TG-DTA), scanning electron micrograph coupled with energy-dispersive X-ray spectroscopy (SEM-EDX) and BET surface area analyzer. The GAC exhibited nearly similar adsorption equilibrium time. Both NO3--N and PO43—P appeared to approach equilibrium after approximately 4 h of agitation time. In the adsorption equilibrium, the removal efficiencies of NO3- -N and PO43--P were found to be 14.6-66.0 % and 52.4-99.0 %, respectively. The adsorption data for NO3--N and PO43--P was correlated to Freundlich and Langmuir isotherm model and the equilibrium data was fitted well to the Langmuir isotherm model due to their higher correlation coefficient (R2) value. The Langmuir adsorption capacity was 1.54 and 2.56 mg g-1 for NO3--N and PO43--P, respectively, which suggests that the GAC is a good adsorbent for removal of NO3--N and PO43—P from water.

The asymmetric unit of the title compound, Ag[Cr(C11H14N2O8)]·3H2O, contains one [Cr(1,3-pdta)]−anion [1,3-pdta is (propane-1,3-diyldinitrilo)tetraacetate], one Ag+cation and three water molecules. The Cr3+ion is coordinated to the four O and two N atoms of the 1,3-pdta ligand, displaying a distorted octahedral geometry. The mean Cr—N and Cr—O bond lengths are 2.0727 (17) and 1.9608 (15) Å, respectively. The conformations of the chelate rings were found to be envelope for the glycinates and twist-boat for the six-membered diamine (T) ring. The Ag+cation is surrounded by six O atoms from three non-coordinated carbonyl O atoms of neighbouring 1,3-pdta groups and three water molecules. The crystal structure is stabilized by intermolecular hydrogen bonding involving the water O—H group as donor and the carboxyl O atom as acceptor.

In this study, Chironomus yoshimatsui larvae were applied to remove Ni(II) and Cr(III) ions from wastewater. The sorption studies were carried out using laboratory-reared C. y. larvae. It was found that C. y. larvae are very susceptible to Cr(III) as compared to Ni(II). The survival capacity of C. y. larvae was sharply reduced when exposed to even low Cr(III) concentration. Sorption isotherm and kinetics of C. y. larvae for Ni(II) were determined by means of controlled experiments in a batch system. It was observed that sorpyion efficiency of Ni(II) was largely concentration dependent and more effective at lower concentration. At each equilibrium, Ni(II) was removed up to roughly 44∼80 %. Sorption data were better fitted to the Langmuir isotherm model because of its correlation coefficient R2 value greater than that of the Freundlich isotherm model. The sorption kinetics by C. y. larvae for Ni(II) was well described a pseudo-first-order rate expression. C. y. larvae have enormous potential for application in wastewater treatment technologies because they are widespread and abundant all around the world and can be easily kept in culture.

A new behavioral endpoint in ecotoxicity testing, burrowing behavior of Chironomus yoshimatsui larvae that survived pre-exposure to 0, 1, 5, and 10 mg/L of cadmium for 96 h was evaluated in a system composed of clean reconstituted water and sand for 5 h, at 30 min intervals. The effective time required for 50% of the introduced larvae to burrow (ET50), the proportion of the maximum burrowing rate reached during a 5 h period (BR5h), and the area under the curve at 5 h (AUC5h) were calculated based on the fitted relationship between burrowing rate and elapsed time. These effect parameters were chosen because they take into account either the burrowing speed of the larvae (ET50), or the proportion of the maximum burrowing rate reached during a 5 h period (BR5h), or both (AUC5h). We found that higher cadmium concentrations resulted in longer ET50 and lower AUC5h values. Additionally, field water samples were collected from streams near residential, natural, agricultural, and industrial areas in Ansan City, Korea in 2014 and 2015, and were used to validate the proposed burrowing test method. The results of the burrowing tests with field collected water samples also confirmed the sensitivity of burrowing activity as an ecotoxicity endpoint, indicated by the large differences among the ET50, BR5h, and AUC5h across the sampling sites and dates with industrial sites strongly affecting burrowing behavior. This study clearly showed that the proposed burrowing test could provide information that would not be detected with the existing acute toxicity tests, within a relatively short time, and can therefore be used as a complement to existing chemical analyses and acute toxicity tests.

In this study, a natural loess soil was evaluated as an adsorbent of Li+ in seawater. Only Li+ was adsorbed preferentially by loess over other cations in seawater despite having the lowest concentration. The adsorption studies of Li+ with loess were assessed using the batch equilibration method. In batch adsorption experiment, the various factors such as agitation time, initial concentration, and amount of dose were investigated. Adsorption isotherm and kinetic studies were performed to quantify the adsorption capacity and adsorption rate of Li+ by loess from seawater. The equilibrium data of adsorption were fitted by using the Freundlich and Langmuir isotherm models. It was seen that the Langmuir isotherm is better in describing the adsorption process of Li+ by loess due to its higher correlation coefficient R2 value. The maximum adsorption capacity of loess for Li+ obtained by Langmuir isotherm was 0.193 mg/g. The pseudo-first-order, the pseudo-second-order, and the intra-particle diffusion kinetic models were employed to analyze the time-dependent adsorption rate of Li+. It was found that the adsorption of Li+ closely follows the pseudo-second-order kinetic model, from which a very accurate estimation of the equilibrium adsorption capacity (qe,cal) was achieved, as well as the higher R2. Because of its low-cost and high selectivity towards Li+, loess could be probably an applicable adsorbent for the recovery of Li+ from seawater.

In the title organic–inorganic salt, [CrCl2(tn)2]2[Cr2O7] (tn is propane-1,3-di­amine), the CrIII ions are coordinated by four N atoms from two tn ligands and two chloride ions in a trans geometry, displaying a distorted octa­hedral arrangement. The crystal packing is stabilized by N—H⋯Cl and N—H⋯O hydrogen bonds., The structure of the title compound, [CrCl2(tn)2]2[Cr2O7] (tn = propane-1,3-di­amine; C3H10N2), has been determined from synchrotron data. The asymmetric unit contains one CrIII complex cation and half a [Cr2O7]2− anion. In the complex cation, the CrIII ion is coordinated by the four N atoms of two propane-1,3-di­amine (tn) ligands in the equatorial plane and by two Cl atoms in a trans configuration, displaying a distorted octa­hedral coordination sphere. The two six-membered rings in the complex cation have an anti chair–chair conformation with respect to each other. The mean Cr—N(tn) and Cr—Cl bond lengths are 2.09 (1) and 2.320 (2) Å, respectively. The slightly bent dichromate anion is disordered over two sets of sites (occupancy ratio = 0.7:0.3) and has a staggered conformation. The crystal structure is stabilized by inter­molecular hydrogen bonds involving the NH2 groups of the tn ligands as donors and the O atoms of the [Cr2O7]2− anion and chlorido ligands as acceptors.

In this study, two Cu2+-doped single crystals, [Cu0.02(H1.96L)](ClO4)2 (1) and [Cu0.91(H0.18L)](ClO4)2 (2) (L = 3,14-diethyl-2,6,13,17-tetraazatricyclo(16.4.0.07,12)docosane), were prepared and characterized by elemental and X-ray crystal structural analyses, along with UV–visible, infrared (IR) and electron paramagnetic resonance (EPR) spectroscopies. The asymmetric units of compounds 1 and 2 contain one half of the molecular dication and one doubly disordered perchlorate anion. The macrocyclic ligand in both the Cu2+-doped compounds adopts the most stable trans-III conformation. The Cu–N bond lengths in the range 2.010 (2)–2.055 (3) A are normal, but the long axial Cu1–O3 bonds of 2.836 (3) and 2.729 (3) A for 1 and 2, respectively, may be due to a combination of the Jahn-Teller effect and strong in-plane ligand field. The crystals are stabilized by hydrogen bonds involving the secondary N–H, the N atoms of the macrocycle, and the O atoms of the perchlorate groups.

In the title complex, the Cr3+ ion is coordinated by the four O and two N atoms of the 1,3-pdta ligand, displaying a distorted octa­hedral geometry. The Ag+ cation is surrounded by six O atoms from neighboring 1,3-pdta groups and water mol­ecules., The asymmetric unit of the title compound, Ag[Cr(C11H14N2O8)]·3H2O, contains one [Cr(1,3-pdta)]− anion [1,3-pdta is (propane-1,3-diyldi­nitrilo)­tetra­acetate], one Ag+ cation and three water mol­ecules. The Cr3+ ion is coordinated to the four O and two N atoms of the 1,3-pdta ligand, displaying a distorted octa­hedral geometry. The mean Cr—N and Cr—O bond lengths are 2.0727 (17) and 1.9608 (15) Å, respectively. The conformations of the chelate rings were found to be envelope for the glycinates and twist-boat for the six-membered di­amine (T) ring. The Ag+ cation is surrounded by six O atoms from three non-coordinated carbonyl O atoms of neighbouring 1,3-pdta groups and three water mol­ecules. The crystal structure is stabilized by inter­molecular hydrogen bonding involving the water O—H group as donor and the carboxyl O atom as acceptor.

The direct disposal of polychlorinated biphenyls (PCBs) in transformer oil by polyethylene glycols (PEGs) under basic condition is reported. The transformer oil containing PCBs was treated by the required amounts of PEGs and potassium hydroxide (KOH) for different reaction times and temperatures. Complete reaction produces aryl PEGs, which are the products of nucleophilic aromatic substitution. The relative efficiencies of the PCB treatment process were assessed in terms of destruction and removal efficiency (DRE, %). At the experimental conditions of 100 °C and 7 h, 125 °C and 3 h, and 150 °C and 1 h, average DREs of PCBs better than 99.9999% were attained. In studying the chemical reaction of PCBs with PEG/KOH, it was confirmed that the process led to less chlorinated PCBs through a stepwise process with the successive elimination of chlorines. Particularly, the least chlorinated PCBs such as mono- and di-PCBs were not produced in our study. Furthermore, the treated transformer oil can be reused through simple segregating procedures.

tn chelate rings in thecomplex adopted a stable anti conformation on the coor-dination plane not including syn conformer. However, thedetailed IR and electronic absorption spectral propertieshave not been published yet. In this study, the four elec-tronic bands due to spin-allowed transitions were assigned.Using the observed electronic transitions, a ligand fieldanalysis was performed to determine the metal-ligand bond-ing properties for the coordinated atoms toward chro-mium (III).

Chromium is the seventh most abundant element on earth. 1 It occurs in various oxidation states ranging from Cr(II) to Cr(VI) with trivalent and hexavalent states being the most stable and common in terrestrial environments. The coordination chemistry of chromium(III) complexes is relevant to third generation solar photoconversion scheme. 2 The geometrical isomerism and conformation in transition metal complexes with mixed ligands are very important in the medical application, and likely to be a major factor in determining the antiviral activity and its side-effect. 3,4 2,2Dimethyl-1,3-propanediamine (Me2tn, Fig. 1) is a bidentate ligand that can coordinate to the central metal ion by forming six-membered chelate ring with a chair conformation. The trans-[Cr(Me2tn)2(OH)(H2O)] 2+ can adopt either the trans or cis geometric isomer. In addition, two different kinds of conformation with respect to the chelate rings of Me2tn occur in the trans isomer, as shown in the bottom of Figure 1. The carbon atoms of the two chelate rings of the two conformers may be on the same side (syn conformer) or on the opposite side (anti conformer) of the coordination plane. In the case of trans-anti/syn-[Cr(Me2tn)2Cl2]Cl, trans-anti/ syn-[Cr(Me2tn)2Br2]2Br2·HClO4·H2O and trans-anti/syn[Cr(Me2tn)2Br2]Br, independent syn and anti conformational isomers were found within the same crystals. 5-7 However, structural analyses of trans-anti-[Cr(Me2tn)2(NCS)2]NCS·1/2H2O, trans-anti-[Cr(Me2tn)2Cl2]ClO4, and trans-anti-[Cr(Me2tn)2Cl2]2ZnCl4 indicated that two chelate rings of Me2tn ligands were only in the anti chair-chair conformation. 6-9 The different conformations of the two sixmembered chelate rings of Me2tn ligands may be dependent on the crystallographic disorder, packing forces, hydrated molecules and counter anions in the crystals. The factors which determine the stability of these geometric conformations are subtle and complicated. 5-9 X-ray crystallography is generally used to establish the presence of either conformation but the syn or anti conformer of the six-membered chelate rings cannot be readily discriminated by infrared and visible absorption spectroscopy. The elucidation of the factors that stabilize the either the syn- or anti-conformation in these complex cations continues to be of interest. Here we report the synthesis, crystal structure and spectroscopic properties of the trans-anti-[Cr(Me2tn)2(OH)(H2O)](ClO4)2 with the purpose of elucidating the influence of Odonor ligands occupying the axial positions and counter anions, on the geometry and the conformation referring to the position of the carbon atoms of the Me2tn chelate rings with respect to the equatorial coordination plane.

The aim of the present study is to explore the possibility of utilizing loess for the adsorption of total phosphorous (T-P) and total nitrogen (T-N) in water. Batch adsorption studies were performed to evaluate the influences of various factors like initial concentration, contact time and temperature on the adsorption of T-P and T-N. The adsorption data showed that loess is not effective for the adsorption of T-N. However, loess exhibited much higher adsorption capacity for T-P. At concentration of 1.0 mg L �1 , approximately 97% of TP adsorption was achieved by loess. The equilibrium data were fitted well to the Langmuir isotherm model. The pseudo-second-order kinetic model appeared to be the better-fitting model because it has higher R 2 compared with the pseudo-first-order and intra-particle kinetic model. The theoretical adsorption equilibrium qe,cal from pseudo-second-order kinetic model was relatively similar to the experimental adsorption equilibrium qe,exp. The thermodynamic parameters such as free energy ΔG, the enthalpy ΔH and the entropy ΔS were also calculated.

Cadmium (Cd) has caused serious public health problem due to its toxic nature. It is necessary to find a cost-effective method to dispose of wastewater containing Cd. Chironomid larvae as an alternative to conventional adsorbents were applied to remove Cd from wastewater. The sorption studies of Cd were carried out using laboratory-reared Glyptotendipes tokunagai (Diptera: Chironomidae) larvae. Kinetic and sorption capacity of chironomid larvae for Cd were determined by means of controlled experiments in a batch system. It was observed that removal efficiency of Cd was largely concentration dependent and more effective in lower concentration. At equilibrium, Cd was removed up to roughly 53 %. The sorption kinetics were found to conform to the pseudo-first-order kinetic model with a good correlation. Equilibrium sorption data were best fitted to the both Freundlich and Langmuir isotherm models owing to their correlation coefficient R2 values greater than 0.99. Considering the values obtained from isotherm constants 1/n and r, it is confirmed that Cd is sorbed favorably by chironomid larvae. With its relatively high removal capability for Cd, Chironomid larvae have enormous potential for application in wastewater treatment technologies.

The aim of the present study is to explore the possibility of utilizing fly ash and loess, as alternative to activated carbon, for the adsorption of diazinon in water. Batch adsorption experiment was performed to evaluate the influences of various factors like initial concentration, contact time and temperature on the adsorption of diazinon. The adsorption data shows that fly ash is not effective for the adsorption of diazinon. The equilibrium data for both activated carbon and loess were fitted well to the Freundlich isotherm model. The pseudo-secondorder kinetic model appeared to be the better-fitting model because it has higher R 2 compared to the pseudofirst-order kinetic model. The thermodynamic parameters such as free energy (ΔG), the enthalpy (ΔH) and the entropy (ΔS) were calculated. Contrary to loess, the ΔG values of activated carbon were negative at the studied temperatures. It indicates that the adsorption of diazinon by activated carbon is a favorable and spontaneous process. The positive ΔH values of activated carbon and loess suggest that the diazinon adsorption process is endothermic in nature. In addition, the positive ΔS values show that increased randomness occurs at the solid/ solution surface during the adsorption of diazinon.

A chemical reaction of PBDEs was implemented using the polyethylene glycols (PEGs) and KOH, along with different reaction conditions such as temperatures and times. Removal efficiencies of PBDEs before and after chemical reac- tion were examined by difference of concentration. PBDEs was not removed at lower temperatures of 25 and 50 o C. However, under the increased temperature, removal efficiency of PBDEs in σ-xylene was gradually increased, showing completely removal of PBDEs containing 5−6 bromines on biphenyl frame. When increasing the reaction conditions to 4 hours and 150 o C, removal efficiency of PBDEs reached almost 100%. In studying the reaction of PEGs with PBDEs, it confirmed that the PBDEs led to less bro- minated by PEGs through a stepwise process with the successive elimination of bromines.

The present study is to explore the possibility of utilizing granular activated charcoal (GAC) for the removal of total phosphorous (T-P) and total nitrogen (T-N) in aqueous solution. Batch adsorption studies were carried out to determine the influences of various factors like initial concentration, contact time and temperature. The adsorption data showed that GAC has a similar adsorption capacity for both T-N and T-P. The adsorption degree of T-N and T-P on GAC was highly concentration dependent. It was found that the adsorption capacity of GAC is quite favorable at a low concentration. At concentrations of 1.0 mg L -1 of T-P and 2.0 mg L -1 of T-N, approximately 97 % of adsorption was achieved by GAC. The equilibrium data were fitted well to the Langmuir isotherm model. The pseudo-second-order kinetic model appeared to be the better-fitting model because it has higher R 2 compared with the pseudo-first-order and intra-particle kinetic model. The theoretical adsorption equilibrium q e,cal from pseudo-second-order kinetic model were relatively similar to the experimental adsorption equilibrium q e,exp . To evaluate the effect of thermodynamic parameters at different temperatures, the change in free energy Δ G , the enthalpy Δ H and the entropy Δ S were estimated. Except for adsorption of T-P at 278 K, the Δ G values obtained were all negative at the investigated temperatures. It indicates that the present adsorption system occurs spontaneously. The adsorption process of T-N by GAC was exothermic in nature, whereas T-P showed endothermic behavior. In addition, the positive values of Δ S imply that there was the increase in the randomness of adsorption of T-N and T-P at GAC-solution interface.

The present study is to explore the possibility of utilizing loess and fly ash as well as activated carbon for the adsorptive removal of T-N and T-P in water. Here, we investigated adsorption efficiency and Freundlich constants k and 1/n of each adsorbent. It was found that fly ash has not adsorptive capability for both T-N and T-P in water. Adsorption of T-N from water by loess has not occurred, but showed that adsorption efficiency for T-P reached approximately 57.5% at equi- librium time of 24 hr and room temperature. Activated carbon was shown to be an effective adsorbent for adsorption of T-N from water. Freundlich constant 1/n value of activated carbon represented that adsorptive capability of activated carbon is almost equivalent to loess.

The aim of the present study is to explore the possibility of utilizing loess and fly ash as well as activated carbon for the adsorptive removal of PCBs in transformer oil. Here, we investigated the effect of various factors such as temperature (5, 25, 55), contact time (30 min-3 day) and adsorbent does (1, 2.5, 5, 10 g) in detail. It was found that PCBs adsorption rate from transformer oil by activated carbon is more favored than loess at the equilibrium time of 60 minutes. The equilibrium data for both activated carbon and loess is fitted well to the Freundlich isotherm model. The rate constant and activation energy of PCBs adsorption in transformer oil on each adsorbent was analyzed by fitting a kinetic model at 5, 25 and . From the thermodynamic parameters, the PCBs adsorption process for transformer oil/activated carbon and loess system is spontaneous and endothermic in nature.

The midge samples were undertaken at three streams, representing different surrounding environments, to investigate the contaminant exposure of midge. The content of heavy metals in midge collected in Singil stream were generally higher as a result of input to the industrial effluents with respect to other streams. Adsorption experiments were done to evaluate the possibility of removing contaminants from water with midge. Diazinon and heavy metals were contaminant target compounds in this study. The removal rate of diazinon in water by midge was 60-75%. In the case of Cu, the removal rate was reached around 90% at the lower initial concentration of 1.87 and 0.81 ppm rather than 4.25 ppm. The reduction of concentration of Cr and Cd according to the lapse of time was similar to the Cu, but their removal rates were shown 50% and 60-74%, respectively. The removal rate of Zn by midge represented relatively high level within the experimental condition. No change in concentration of Cr and As with time were occurred at all experimental conditions. It accounts for the fact that the reduction of Cr and As could not be achieved through the adsorption process, using midge.

Practical disposal of transformer insulation oil laden with PCBs (polychlorinated biphenyls) by a chemical treatment has been studied in field work. The transformer insulation oil containing PCBs was treated by the required amounts of PEG (polyethylene glycol) and KOH, along with different reaction conditions such as temperatures and times. The reaction of PEG with PCBs under basic condition produces arylpolyglycols, the products of nucleophilic aromatic substitution. Removal efficiencies of PCBs in insulation oil before and after chemical treatment were examined. The removal efficiency of PCBs was very low at lower temperatures of 25 and . Under the reaction condition of PEG 600/KOH//2hr, removal efficiency of PCBs was approximately 70%, showing completely removal of PCBs containing 7~9 chlorines on biphenyl frame which appear later than PCB IUPAC Number 183 (2,2',3,4,4',5',6-heptaCB) in retention time of GC/ECD. However, when increasing the reaction temperature and time to and 4 hours, removal efficiency of PCBs reached 99.99% without any formation of PCDDS/PCDFs during the process. Such reaction conditions were verified by several official analytical institutions. In studying the reaction of PEG with PCBs, it confirmed that the process of chemical treatment led to less chlorinated PCBs through a stepwise process with the successive elimination of chlorines.

A practical and efficient disposal method for chemical dechlorination of PCBs (polychlorinated biphenyls) in transformer oil was evaluated. The transformer oil containing PCBs was treated by the PEG 600 (polyethylene glycol 600) and potassium hydroxide (KOH) along with different reaction temperatures(25, 50, 100 and ) and times(30, 60, 240 and 480 min). The best disposal efficiency of PCBs in transformer oil was attained under the experimental conditions of PEG 600 (2.5 w/w%)/KOH (2.5 w/w%)//4 hrs, showing completely removal of all PCBs containing 3-9 chlorines on two rings of biphenyl. In studying the reaction of PEG/KOH with PCBs, it confirmed that the process led to less chlorinated PCBs through a stepwise process with the successive elimination of chlorines.

The enantiomeric signatures of organochlorine pesticides were measured in air masses from Okinawa, Japan and three remote locations in the Pacific Northwestern United States: Cheeka Peak Observatory (CPO), a marine boundary layer site on the Olympic Peninsula of Washington at 500 m above sea level (m.a.s.l); Mary's Peak Observatory (MPO), a site at 1250 m.a.s.l in Oregon's Coast range; and Mt. Bachelor Observatory (MBO), a site at 2763 m.a.s.l in Oregon's Cascade range. The enantiomeric signatures of composite soil samples, collected from China, South Korea, and the western U.S. were also measured. The data from chiral analysis was expressed asthe enantiomeric fraction, defined as (+) enantiomer/(sum of the (+) and (-) enantiomers), where a racemic composition has EF = 0.5. Racemic alpha-hexachlorocyclohexane (alpha-HCH) was measured in Asian air masses at Okinawa and in Chinese and South Korean soils. Nonracemic alpha-HCH (EF = 0.528 +/- 0.0048) was measured in regional air masses at CPO, and may reflect volatilization from the Pacific Ocean and regional soils. However, during trans-Pacific transport events at CPO, the alpha-HCH EFs were significantly more racemic (EF = 0.513 +/- 0.0003, p < 0.001). Racemic alpha-HCH was consistently measured at MPO and MBO in trans-Pacific air masses that had spent considerable time in the free troposphere. The alpha-HCH EFs in CPO, MPO, and MBO air masses were negatively correlated (p = 0.0017) with the amount of time the air mass spent above the boundary layer, along the 10-day back air mass trajectory, prior to being sampled. This suggests that, on the West coast of the U.S., the alpha-HCH in the free troposphere is racemic. Racemic signatures of cis- and trans-chlordane were measured in air masses at all four air sampling sites, suggesting that Asian and U.S. urban areas continue to be sources of chlordane that has not yet been biotransformed.

A comprehensive quality survey for heavy metals, organophosphorous and organochlorine residual pesticides, and coplanar PCBs in samples such as water, sediments and soils as well as spiders has been implemented. The samples were undertaken at nine stream sites and their vicinity in August 2006, representing different surrounding environments. The levels of PCBs were expressed as concentrations and WHO-TEFs. Among 12 coplanar PCBs as target compounds in this study, 2,3', 4,4', 5-PentaCB (IUPAC # 118) was the congener with the highest concentration. The total concentrations and TEF values of coplanar PCBs in Siheung stream sediment (heavy industrial complex site located in Ansan city) were 3915.50 pg/g and 0.8366 pg-TEQ/g on a dry weight basis, respectively. Such levels were around 40 times higher compared to sediment from Gapyung stream (green site located in the upper of Myunggi mountain). It is probably due to the direct input of PCBs trom PCBs treatment materials. Organophosphorous (EPN, dementon-s-methyl, diazinon, parathion, and phenthoate) and organochlorine (alpha-BHC, aldrin, 4,4'-DDT, 4,4'-DDE, endosulfan alpha and etc.) pesticides were not detected above 5 ppb of detection limits. The concentrations of Cu and Cd in water and sediment samples from Siheung stream were 44.11 and and and , respectively, which contained times higher concentrations than those from Gapyung stream. In addition to the water and sediment samples, the levels of heavy metals in spider from designated sampling sites were also determined. Heavy metals in spider collected near Siheung stream was appeared to be equivalent and/or a little higher levels with respect to other spiders. Furthermore, the ratio of relative heavy metals (Cu, Cd, and Pb) in spider from each stream site showed a correlation as similar as that of heavy metals in soil samples.