2,8,15,18,21,24,31,37,44,47,50,53-Dodeca-oxahepta-cyclo-[52.4.0.0(4,35).0(6,33).0(9,14).0(25,30).0(38,43)]octa-penta-conta-1(54),4,6(33),9(14),10,12,25(30),26,28,34,38(43),39,41,55,57-penta-deca-ene di-chloro-methane disolvate.

In the title compound, C46H50O12·2CH2Cl2, each dual 20-crown-6 unit crystallizes with two di-chloro-methane solvent mol-ecules. The crown unit mol-ecule lies about an inversion centre located at the central benzene ring. The two crown ring groups adopt an anti conformation, stabilized by weak intra-molecular C-H⋯O inter-actions. In the crystal, the crown unit mol-ecules and the solvent mol-ecules are linked by C-H⋯O inter-actions into a three-dimensional network.

Hard and soft metal complexes of calix[4]-bis-monothiacrown-5: X-ray and NMR studies of discrete homodinuclear complexes and a heteromultinuclear network.

Endocyclic homodinuclear complexation and endo/exocyclic heteronuclear networking of calix[4]-bis-monothiacrown-5 (L) are reported. First, dipotassium(I) and disilver(I) complexes of L were isolated and their solid state structures characterized. To probe the complexation behavior for these same systems in solution, the competition between potassium(I) and silver(I) for L was monitored by (1)H NMR. Potassium(I) showed a higher affinity to L than silver(I) both in the solid and solution states. The reaction of L with KI in the presence of HgI2 afforded a two-dimensional coordination polymer with the endocyclic dipotassium(I) complex linked by an exocyclic mercury(II) iodide cluster backbone.

9-[3-(Carbazol-9-yl)-5-methyl-phen-yl]carbazole.

The title compound, C31H22N2, crystallizes with two symmetry-independent mol-ecules in the asymmetric unit. The mol-ecules have slightly different conformations, the dihedral angles between the central phenyl ring and the carbazolyl groups being 56.29 (4) and 59.57 (4)° in one mol-ecule and 48.71 (4) and 65.47 (4)° in the other. In the crystal, mol-ecules are linked by weak C-H⋯π and π-π [centroid-centroid distances = 3.7698 (10), 3.8292 (9), 3.9429 (10) and 3.9431 (10) Å].

Zinc-chelated Vitamin C Stimulates Adipogenesis of 3T3-L1 Cells.

Adipose tissue development and function play a critical role in the regulation of energy balance, lipid metabolism, and the pathophysiology of metabolic syndromes. Although the effect of zinc ascorbate supplementation in diabetes or glycemic control is known in humans, the underlying mechanism is not well described. Here, we investigated the effect of a zinc-chelated vitamin C (ZnC) compound on the adipogenic differentiation of 3T3-L1 preadipocytes. Treatment with ZnC for 8 d significantly promoted adipogenesis, which was characterized by increased glycerol-3-phosphate dehydrogenase activity and intracellular lipid accumulation in 3T3-L1 cells. Meanwhile, ZnC induced a pronounced up-regulation of the expression of glucose transporter type 4 (GLUT4) and the adipocyte-specific gene adipocyte protein 2 (aP2). Analysis of mRNA and protein levels further showed that ZnC increased the sequential expression of peroxisome proliferator-activated receptor gamma (PPARγ) and CCAAT/enhancer-binding protein alpha (C/EBPα), the key transcription factors of adipogenesis. These results indicate that ZnC could promote adipogenesis through PPARγ and C/EBPα, which act synergistically for the expression of aP2 and GLUT4, leading to the generation of insulin-responsive adipocytes and can thereby be useful as a novel therapeutic agent for the management of diabetes and related metabolic disorders.

2,9,12,15,18,25,27,34,37,40,43,50-Dodeca-oxa-56-aza-hepta-cyclo-[24.24.5.1(51,55).0(3,8).0(19,24).0(28,33).0(44,49)]hexa-penta-conta-3,5,7,19(24),20,22,28(33),29,31,44,46,48,51,53,55-penta-deca-ene.

The title compound, C(43)H(45)NO(12), was prepared from the reaction of 2,6-bis-(dibromo-meth-yl)pyridine and bis-phenol in the presence of caesium carbonate as a base. The central ring makes dihedral angles of 64.83 (6), 13.48 (6), 56.96 (6) and 66.21 (6)° with the peripheral rings. In the crystal, mol-ecules are linked by weak C-H⋯O and C-H⋯π inter-actions, forming a folded structure.

6,7-Bis(bromo-meth-yl)-2,11,18,21,24,27-hexa-oxatetra-cyclo-[26.4.0.0.0]dotriaconta-1(28),4,6,8,12(17),13,15,29,31-nona-ene dichloro-methane monosolvate.

The title 20-crown-6 unit, C(28)H(30)Br(2)O(6)·CH(2)Cl(2), consisting of three benzo groups and triethyl-ene glycol was prepared from the reaction of 1,2,4,5-tetra-kis-(bromo-meth-yl)benzene and bis-phenol in the presence of sodium hydride. In the crystal, one O atom of the central ethyl-ene glycol in the triethyl-ene glycol unit exhibits an exo conformation as a result of intra-molecular C-H⋯O hydrogen bonds. The crown unit and the solvent mol-ecule are linked by weak C-H⋯O hydrogen bonds.

Hard/soft heterometallic network complex of a macrocycle with endo/exocyclic coordination.

One-pot assembly reactions of an S(2)O(4) macrocycle with CuI in the absence and presence of KI afforded an emissive one-dimensional looped coordination polymer linked with a cubane-type copper iodide cluster and an endocoordinated potassium(I) coordination polymer linked with a ribbon-type copper iodide cluster, respectively.

Catalytic conversion of 1,2-dichlorobenzene over mesoporous materials from zeolite.

In this study, 1,2-dichlorobenzene (DCB), an important precursor of PCDDs and PCDFs, was chosen as a suitable model compound for the catalyzed deep oxidation of dioxin. The recently developed mesoporous materials from zeolites (MMZ) were used for the first time as a support for an oxidation catalyst. The catalytic oxidation of 1,2-dichlorobenzene over Pt/MMZ was carried out, and the catalytic activity was compared with that of Pt/gamma-Al2O3, Pt/Al-MCM-41 and Pt/Beta catalysts. Pt/MMZ showed the highest catalytic activity among the catalysts tested. Interestingly, the catalytic activity of Pt/MMZ was maintained (> 40%) at low temperatures (250 degrees C) at which the other catalysts showed extremely low activity (< 5%). The high catalytic activity of Pt/MMZ was attributed to both the sufficient acidity and mesoporosity of the MMZ support.

Ability of Beijerinckia indica to degrade phenanthrene and reduce hydraulic conductivity.

This study evaluates the ability of Beijerinckia indica (B. indica) as a biomaterial for aerobic biofilm barriers. B. indica's ability to remove phenanthrene was measured using a two-phase partitioning bioreactor. Approximately 500 mg/L of phenanthrene was gradually removed over a two week period under aerobic conditions of the bioreactor. B. indica's ability to reduce hydraulic conductivity was evaluated using rigid wall soil columns inoculated with the bacteria. B. indica formed a large quantity of strongly adhesive biofilm among soil particles, reducing the hydraulic conductivity in the soil columns by 2 or 3 orders of magnitude. To assess recovery of the biofilm, the formed biofilm was purposely destroyed by introducing landfill leachate into the soil columns. The biofilm recovery test showed that the hydraulic conductivity increased after leachate introduction. However, re-permeation of nutrient solution restored the permeability to its original lower value, which suggests a full recovery of the damaged biofilm. This study suggests that B. indica may be used as a possible biomaterial for aerobic biofilm barriers for the removal of phenanthrene from groundwater, provided that sufficient substrate and electron acceptor are provided to the treatment system.

Stability of multi-permeable reactive barriers for long term removal of mixed contaminants.

The Permeable Reactive Barriers (PRBs) are relatively simple, promising technology for groundwater remediation. A PRBs consisting of two reactive barriers (zero valent iron-barrier and bio-barrier) were designed to evaluate the application and feasibility of the barriers for the removal of wide range of pollutants from synthetic water. After 470 days of Multi-PRBs column operation, the pH level in the water sample is increased from 4 to 7, whereas the oxidation reduction potential (ORP) is decreased to -180 mV. Trichloroethylene (TCE), heavy metals, and nitrate were completely removed in the zero valent iron-barrier. Ammonium produced during nitrate reduction is removed in the biologically reactive zone of the column. The results of the present study suggest that Multi-PRBs system is an effective alternate method to confine wide range of pollutants from contaminated groundwater.

Unsymmetrical calixcrowns incorporating hard and soft loops as a new scaffold for multinuclear endo/exocyclic complexation and networking.

Unsymmerical calix[4]crowns containing [(O(4)S)(O(5))] (L(1)) and [(O(4)S(2))(O(5))] (L(2)) as crown loops were employed as new scaffolds both for complexation studies and for network formation. Reactions of L(1) and L(2) with KI in the presence of CuI afforded a copper(I) iodide cluster linked 1D-type endocyclic dipotassium(I) complex [K(2)(L(1))(Cu(7)I(9))](n) (1) and a copper(I) iodide cluster linked 1D-type endocyclic monopotassium(I) complex [KL(2)(mu(2)-Cu(3)I(4))](n) (2), respectively. By comparison, the reaction of L(2) with KPF(6) in the presence of CuI and HgI(2) afforded the 1-D endocyclic potassium(I) complex [K(L(2))(CuHgI(4))](n) (3), linked with a CuHgI(4) cluster unit. The formation of homo- and heterodinuclear complexes in solution was also confirmed by comparative NMR studies.

2,9,16,19,22,25-Hexaoxatetra-cyclo-[24.4.0.2.0]dotriaconta-1(26),4,6,10(15),11,13,27,29,31-nona-ene.

The title 22-crown-6 unit, C(26)H(28)O(6), comprising of three benzo groups and triethyl-ene glycol, was prepared by the reaction of α,α'-dibromo-p-xylene with 1,8-bis-(2-hydroxy-phen-oxy)-3,6-dioxaoctane in the presence of Cs(2)CO(3) with tetra-hydro-furan (THF) and recrystallized from dichloro-methane-hexane (1:20 v/v) at room temperature. In the mol-ecular structure, two O atoms of the central ethyl-ene glycol in the triethyl-ene glycol unit exhibit exo conformations due to intra-molecular C-H⋯O inter-actions. A number of C-H⋯O and C-H⋯π inter-molecular inter-actions contribute to the stabilization of the crystal packing.

Networking of calixcrowns: from heteronuclear endo/exocyclic coordination polymers to a photoluminescence switch.

Solvato-PL switching and shrinking-and-opening process: we present two CuI coordination polymers of calix[4]-bis-monothiacrown (L) obtained in the absence (1) and presence (2) of KI. The structures show not only very unusual CuI-based network arrangements but also unique reversible photolunimescence switching behavior induced by removal of coordinated solvent. Furthermore, upon inclusion of K+ ions the crown ring shrinks leading to "opening" of opposite aromatic rings in the host calixarene unit, rare behavior for this class of compound.

Temperature-dependent 3-D CuI coordination polymers of calix[4]-bis-dithiacrown: crystal-to-crystal transformation and photoluminescence change on coordinated solvent removal.

The temperature-dependent assembly of two 3-D CuI coordination polymers containing calix[4]-bis-thiacrown with different networking motifs are reported. Upon removal of the coordinated solvent molecules the initial solvent-coordinated polymer undergoes a unique single-crystal-to-single-crystal transformation to the desolvated polymer. Structural characteristics observed in the solvent-coordinated and the desolvated polymers also reveal related solvato-photolunimescence "off-on" behavior.

Calix[4]thiacrowns as ditopic hosts for homo- and heterobinuclear accommodation: first report of a chopsticks-type pi-coordination.

[reaction: see text] Calix[4]thiacrowns with hetero-L(1) and a homodonor set (L(2)) were synthesized and characterized by X-ray analysis. From the reaction of L(2) with AgPF(6), disilver complex [Ag(2)(L(2))](PF(6))(2) (1) was isolated. By comparing 1,3-alternate conformations of L(2) and 1, we found a considerable decrease of dihedral angles of two opposite aromatic rings upon complexation. This finding can be explained in terms of the "chopsticks process", which illustrates how Ag(+)-arene pi-coordination occurs. Heterobinuclear complexation of L(1) in solution was also observed.

Toxic effects of di(2-ethylhexyl)phthalate on mortality, growth, reproduction and stress-related gene expression in the soil nematode Caenorhabditis elegans.

In this study, di(2-ethylhexyl)phthalate (DEHP) toxicities to Caenorhabditis elegans were investigated using multiple toxic endpoints, such as mortality, growth, reproduction and stress-related gene expression, focusing on the identification of chemical-induced gene expression as a sensitive biomarker for DEHP monitoring. The possible use of C. elegans as a sentinel organism in the monitoring of soil ecosystem health was also tested by conducting the experiment on the exposure of nematode to field soil. Twenty-four-hour median lethal concentration (LC50) data suggest that DEHP has a relatively high potential of acute toxicity to C. elegans. Decreases in body length and egg number per worm observed after 24h of DEHP exposure may induce long-term alteration in the growth and reproduction of the nematode population. Based on the result from the C. elegans genome array and indicated in the literatures, stress proteins, metallothionein, vitellogenin, xenobiotic metabolism enzymes, apoptosis-related proteins, and antioxidant enzyme genes were selected as stress-related genes and their expression in C. elegans by DEHP exposure was analyzed semi-quantitatively. Expression of heat shock protein (hsp)-16.1 and hsp-16.2 genes was decreased by DEHP exposure. Expression of cytochrome P450 (cyp) 35a2 and glutathione-S-transferease (gst)-4, phase I and phase II of xenobiotic metabolism enzymes, was increased by DEHP exposure in a concentration-dependent manner. An increase in stress-related gene expressions occurred concomitantly with the deterioration on the physiological level, which suggests an increase in expression of those genes may not be considered as a homeostatic response but as a toxicity that might have physiological consequences. The experiment with the soil from the landfill site suggests that the potential of the C. elegans biomarker identified in laboratory conditions should be calibrated and validated for its use in situ.

Hydrogen storage in ni nanoparticle-dispersed multiwalled carbon nanotubes.

Hydrogen storage properties of mutiwalled carbon nanotubes (MWCNTs) with Ni nanoparticles were investigated. The metal nanoparticles were dispersed on MWCNTs surfaces using an incipient wetness impregnation procedure. Ni catalysts have been known to effectively dissociate hydrogen molecules in gas phase, providing atomic hydrogen possible to form chemical bonding with the surfaces of MWCNTs. Hydrogen desorption spectra of MWCNTs with 6 wt % of Ni nanoparticles showed that approximately 2.8 wt % hydrogen was released in the range of 340-520 K. In Kissinger's plot to evaluate the nature of interaction between hydrogen and MWCNTs with Ni nanoparticles, the hydrogen desorption activation energy was measured to be as high as approximately 31 kJ/mol.H(2), which is much higher than the estimates of pristine SWNTs. C-H(n)() stretching vibrations after hydrogenation in FTIR further supported that hydrogen molecules were dissociated when bound to the surfaces of MWCNTs. During cyclic hydrogen absorption/desorption, there was observed no significant decay in hydrogen desorption amount. The hydrogen chemisorption process facilitated by Ni nanopaticles could be suggested as an effective reversible hydrogen storage method.

Characterization of humic substances in landfill leachate and impact on the hydraulic conductivity of geosynthetic clay liners.

A detailed characterization was performed on the humic substances present in landfill leachate derived from the older (10-year) and younger (6-month) municipal landfill cells at a site in Inchion, Korea. The characterization focused on the humic and fulvic acid components of the leachate, relying on information gleaned from the UV/visible spectroscopy, molecular weight distribution, and Fourier transform infrared spectroscopy. The effect of the leachates, and specific components of the leachates, on the hydraulic conductivity of a geosynthetic clay liner (GCL), was evaluated. The humic acid extracted from the older leachate was composed primarily of high molecular weight and aromatic compounds, which is typical for humic acids. However, the humic acid extracted from the younger leachate showed characteristics more similar with fulvic acids, indicating that the younger humic acid was at the initial stage of humification. The hydraulic conductivity of the GCLs to the humic and fulvic acids of the older and younger leachate was similar to those permeated with the distilled deionized water (DI). However, the hydraulic conductivity of the samples tested with the raw leachate was more than 200 times the DI value. This fact suggests that cations present in leachate, rather than humic substances, are the key factor in the increase of the permeability.