Abstract  Abstract: Separation of Cs⁺ from acidic solution was investigated using ammonium molybdo- phosphate (AMP) based sorbents. Four sorbents including two AMP powders and two composites prepared by coating of AMP powder on polymethylmethacrylate (PMMA) beads were used in this study. Equilibrium sorption isotherms for Cs⁺ on AMP sorbents were determined. The effect of H⁺ concentration on Cs⁺ uptake by AMP–PMMA beads was examined. Two column runs were carried out to establish the Cs⁺ separation performance of AMP–PMMA beads from 1.0 M nitric acid having Cs⁺ concentration equivalent to 10 Ci of ¹³⁷Cs per litre. Recovery of Cs⁺ from loaded AMP–PMMA column was carried out by dissolution of AMP using NaOH solution. The feasibility of ion exchange purification of the recovered Cs⁺ solution was examined using resorcinol formaldehyde polycondensate resin (RFPR). The Cs⁺ sorption isotherm on RFPR from Cs-bearing dissolved AMP solution was determined. Purification of Cs⁺ from dissolved AMP solution was studied in two column runs using RFPR in loading-elution cycles. The results of these studies are useful in formulating a scheme for the recovery of purified ¹³⁷Cs product from high level waste for large-scale utilization as a radiation source in industrial irradiators. [Copyright 2008 Elsevier] Copyright of Desalination is the property of Elsevier Science Publishers B.V. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts)

Abstract  The abundant lignocellulosic agricultural waste, coir pith is used to develop ZnCl(2) activated carbon and applied to the removal of toxic anions, heavy metals, organic compounds and dyes from water. Sorption of inorganic anions such as nitrate, thiocyanate, selenite, chromium(VI), vanadium(V), sulfate, molybdate, phosphate and heavy metals such as nickel(II) and mercury(II) has been studied. Removal of organics such as resorcinol, 4-nitrophenol, catechol, bisphenol A, 2-aminophenol, quinol, O-cresol, phenol and 2-chlorophenol has also been investigated. Uptake of acidic dyes such as acid brilliant blue, acid violet, basic dyes such as methylene blue, rhodamine B, direct dyes such as direct red 12B, congo red and reactive dyes such as procion red, procion orange were also examined to assess the possible use of the adsorbent for the treatment of contaminated ground water. Favorable conditions for maximum removal of all adsorbates at the adsorbate concentration of 20 mg/L were used. Results show that ZnCl(2) activated coir pith carbon is effective for the removal of toxic pollutants from water.

Abstract  We have investigated the influence of peroxides on DNA adduct formation in HL-60 cells treated with polyphenolic metabolites of benzene. Treatment of HL-60 cells with 50 mu M hydroquinone (HQ), 500 mu M catechol (CAT) or 200 mu M 1,2,4-benzenetriol (BT) resulted in adduct levels of 0.27, 0.21 and 0.21 x 10(-7), respectively. Addition of 50-250 mu M H2O2 or 250 mu M cumene hydroperoxide to HL-60 cells increased DNA adduct formation 2.7-10-fold following treatment with HQ or CAT but had no effect on adduct formation by BT. Treatment of HL-60 cells with the combinations of HQ plus either BT or phorbol myristate acetate (PMA) potentiated DNA adduct formation by 2.5-4-fold. Significant elevations of cellular H2O2 levels occurred after treatment of HL-60 cells with either PMA, CAT or BT. These results indicate that cellular levels of H2O2 regulate the peroxidase dependent activation of benzene metabolites to form DNA adducts. (C) 1996 Academic Press. Inc.

Abstract  An enrichment-separation procedure basedn the coprecipitationf gold(III), palladium(II) and lead(II)ons with nickel(II)-5-methyl-4-(2-thiazolylazo) resorcinol complex has beeneveloped. The analytical parametersncluding pH, amountsf 5-methyl-4-(2-thiazolylazo) resorcinol, sample volume, etc. wasnvestigated for quantitative recoveriesf Au(III), Pd(II) and Pb(II). Interferenceue to various cations and anions has also beennvestigated. Theetection limits for analyteons by 3sigma were 2.6 microg L(-1) for lead, 1.5 microg L(-1) for gold, 2.1 microg L(-1) for palladium. The accuracyf the method was evaluated by the analysisf certified reference materials (NIST SRM 2711 Montana soil, GBW 07309 Stream sediment). The proposed procedure was successfully applied to environmental samples for theeterminationsf analytes.

Abstract  Tabershaw Occupational Medicine Associates, PA (TOMA) performed medical examinations and evaluations of the workers at Koppers' Bridgeville, Pennsylvania plant in May and June 1981. Of the 246 eligible workers, 139 (56.5%) were examined. While this is not a large proportion of workers, there is fairly good representation across all age groups. The medical examinations, tests, and evaluations were geared specifically for the potential occupational exposures at the plant. Special tests were therefore used to detect abnormalities in physiology and health that might be caused by work exposures. There were no diseases or abnormalities found that can be definitely related to effects of work exposures. There was one case of lung cancer detected in a 64-year-old cigarette smoker. It is not possible to say definitely if there is any relationship between work exposures and the development of lung cancer in this man, but the long history of cigarette smoking would implicate this as a causative factor. There were nine cases of possible minimal pneumoconiosis by chest x-ray. In addition, four of these individuals also had pleural thickening. Three others had pleural thickening without other complications. We do not have any information to indicate there were work exposures at this plant that would cause these abnormalities detected in the x-ray. There were no other abnormalities detected in the workers in greater proportion than in the general population of the same age groups. Specifically, there were fewer than expected skin lesions and no skin cancers found. There was no evidence of thyroid or immunological abnormalities. There also was no excess number of abnormalities in the hematological system. In the 1978 study, 13 cases of eosinophilia were observed, a higher than expected prevalence. Only seven of these 13 were retested in 1981. The results were all normal except for one case and his results were only slightly elevated. Five other workers also had elevated eosinophils, but the levels were not severe and there was no evidence of associated disease. There were several workers who bad abnormalities, generally minor, not related to work. Each worker was counseled about the findings and advised to see his/her personal physician as appropriate.

Abstract  The applicability of derivative spectrophotometry for simultaneous determination of zinc(II), manganese(II) and iron(II) in the form of PAR complexes was presented and discussed. Beer's law was obeyed in range 0.025-13 ppm for zinc 1û20, for manganese and 0.025-0.2 for iron ion. The elaborated method was applied successfully for determination of mentioned ions in pharmaceutical preparation without previous separation. The error of the determination did not exceed ±3%.

Abstract  Bambusae Caulis in Liquamen (BCL) is the distilled product of the condensation from the burning of Phyllostachys nigra var. henosis (Gramineae). The activity-guided isolation of BCL yielded four phenolic compounds: 2,6-dimethoxyphenol (1), 1,2-dihydroxybenzene (2), 1,3-dihydroxybenzene (3) and 1,2-dibenzenecarboxylic acid (4). We evaluated the anti-oxidative, anti-inflammatory and whitening effects of these compounds, via assays, of 1,1-diphenyl-2-picrylhydazyl (DPPH) radical scavenging activity and inhibition of nitric oxide (NO) production in lipopolysaccharide-stimulated RAW 264.7 macrophage cells as well as inhibition of tyrosinase activity and melanin production in B16F10 melanoma cells. The results showed that 2 and 3 exhibited significant DPPH radical scavenging activity as well as inhibitory effects on NO production, tyrosinase activity and melanin production. These results suggested that BCL and compounds 2 and 3 can be developed as anti-oxidative, anti-inflammatory and whitening ingredients.

Abstract  Groups of 6-week-old male Syrian golden hamsters were given 13 different phenolic compounds for 20 weeks. Of these compounds, 2(3)-tert-butyl-4-methoxyphenol (BHA), 2-tert-butyl-4-methylphenol (TBMP) and p-tert-butylphenol (PTBP) strongly induced hyperplasia and tumorous lesions in the forestomach. Catechol, p-methylphenol (PMYP), p-methoxyphenol (PMOP), caffeic acid, methylhydroquinone (MHQ) and pyrogallol were less active, and resorcinol, hydroquinone, propylparabene and tert-butylhydroquinone (TBHQ) were not active. The labelling index in the forestomach epithelium was significantly increased by addition to the diet of BHA, TBMP, catechol, PMOP, PTBP and MHQ. PMOP induced epithelial damage and regenerative hyperplasia of the pyloric region. Catechol, caffeic acid and PMYP induced similar though less marked lesions. The labelling index in the glandular stomach was significantly increased by oral catechol (P less than 0.05) or PMOP (P less than 0.05). No histopathological lesions were observed in the urinary bladder epithelium, but propylparabene (P less than 0.05), catechol, TBHQ and MHQ increased the labeling index. These findings indicate that PTBP and TBMP may be carcinogenic for hamster forestomach after long-term administration, and that both one hydroxy and tert-butyl substituents may be important for induction of hamster forestomach tumors.

Abstract  N/A.

Abstract  #Modifying effects of the environmental contaminant catechol, and its isomers resorcinol and hydroquinone, on methyl-N-amylnitrosamine (MNAN)-induced carcinogenesis were studied in male F344 rats. Groups of 15 rats were given three i.p. injections of 25 mg/kg of body weight of MNAN within the initial 2-wk period, and commencing 1 wk thereafter they were administered 0.8% catechol, 0.8% resorcinol, or 0.8% hydroquinone in powdered basal diet or were given basal diet alone for 49 wk. Additional groups of 10 to 15 rats were similarly treated without prior carcinogen exposure. Histological examination after sacrifice at wk 52 revealed that the incidences of tongue papillomas and esophageal squamous cell carcinomas in the groups given MNAN followed by catechol (57.1% and 64.3%) or resorcinol (50% and 58.8%) were significantly higher than those in the carcinogen only controls (9.1, and 0%, respectively). Hydroquinone also enhanced the development of esophageal squamous cell carcinomas but was less active than catechol or resorcinol. The incidence of alveolar hyperplasia in the lungs of the group given MNAN followed by catechol (0%) was, in contrast, significantly reduced as compared to the control value (54.5%). Hydroquinone and resorcinol showed a similar but nonsignificant tendency. These results indicated that the environmental contaminant, catechol and its isomers, may play a role in the development of human upper gastrointestinal cancer, in addition to exerting modifying effects in other organs.

Abstract  It was found that the weak chemiluminescence produced from the reaction of polyhydroxy phenols with luminol in alkaline solution could be strongly enhanced by ferricyanide and ferrocyanide. Based on this found, a new flow injection chemiluminescence method is proposed for the determination of four polyhydroxy phenols: pyrogallol, phlorglucinol, quinol and resorcinol. The detection limits of the method are 0.03 mug ml(-1) pyrogallol, 0.03 mug ml(-1) phlorglucinol, 0.04 mug ml(-1) quinol, and 0.02 mug ml(-1) resorcinol. The possible mechanism of CL reactions is also discussed briefly.

Abstract  Nanoparticles of NaAlH(4) have been infiltrated in nanoporous carbon aerogel with TiCl(3) nanoparticles in order to explore possible synergetic effects between nanoconfinement and a functionalized catalytic scaffold. Resorcinol formaldehyde carbon aerogels with an average pore size of 17 nm and total pore volume of 1.26 mL/g were infiltrated with TiCl(3) to obtain an aerogel doped with 3.0 wt % TiCl(3) nanoparticles. NaAlH(4) was melt-infiltrated into the functionalized carbon aerogel at 189 °C and p(H(2)) ∼ 186-199 bar. Energy-dispersive spectrometry (EDS) combined with focused ion beam (FIB) techniques revealed the presence of Na, Al, Ti, and Cl inside the aerogel scaffold material. The infiltrated NaAlH(4) was X-ray amorphous, whereas (27)Al magic-angle spinning (MAS) NMR spectroscopy confirmed the presence of nanoconfined NaAlH(4). Temperature-programmed desorption mass spectroscopy (TPD-MS) and Sieverts' measurements demonstrated significantly improved hydrogen desorption kinetics for this new nanoconfined NaAlH(4)-TiCl(3) material as compared to nanoconfined NaAlH(4) without the catalysts TiCl(3) and to bulk ball-milled samples of NaAlH(4)-TiCl(3). We find that the onset temperature for hydrogen release was close to room temperature (T(onset) = 33 °C), and the hydrogen release rate reached a maximum value at 125 °C, which demonstrates favorable synergetic effects between nanoconfinement and catalyst addition.

Abstract  Carbon aerogels are a unique class of high-surface-area materials derived by sol-gel chemistry. Their high mass-specific surface area and electrical conductivity, environmental compatibility and chemical inertness make them very promising materials for many energy related applications, specifically in view of recent developments in controlling their morphology. In this perspective we will review the synthesis of monolithic resorcinol-formaldehyde based carbon aerogels with hierarchical porosities for energy applications, including carbon nanotube and graphene composite carbon aerogels, as well as their functionalization by surface engineering. Applications that we will discuss include hydrogen and electrical energy storage, desalination and catalysis.

Abstract  Acrolein, four methacrylates, two guanidine compounds and resorcinol were tested for embryotoxicity on three day chicken embryos. The most potent chemical was acrolein, with the ED50 0.05 mumol per egg for the total effect, including deaths and malformations. The substances next in potency were N,N'-di-o-tolyl-guanidine and N,N-diphenylguanidine, with ED50 values 0.17 and 0.20 mumol per egg, respectively. Resorcinol and the methacrylates had ED50 values ranging from 2.4 to 22.0 mumol per egg. Acrolein, diphenylguanidine, tetrahydrofururylmethacrylate and trimethylolpropanetrimethacrylate caused the largest amounts of malformed embryos.

Abstract  Bromodichloromethane (99% pure), one of several trihalomethanes commonly formed after chlorination of water, was selected for study because no carcinogenicity data were available for this compound and because chloroform, a related trihalomethane, had been found to cause tumors in rodents. The general population might be exposed to bromodichloromethane in drinking water supplies, in swimming pools, and in a variety of food substances. Single-administration, 14-day, 13-week, and 2-year studies were conducted in F344/N rats and B6C3F1 mice. The chemical was administered by gavage in corn oil because human exposure is primarily oral. Additional studies were performed to evaluate the potential for genetic damage in bacteria and mammalian cells. Results of the short-term studies In the single-administration studies, the chemical was administered at doses of 150-2,500 mg/kg per day. All rats and female mice at 1,250 and 2,500 mg/kg and all male mice at 600, 1,250, and 2,500 mg/kg died; 2/5 male rats, 1/5 female rats, and 2/5 female mice at 600 mg/kg died; all animals at lower dose levels survived. In the 14-day studies, rats received doses of 38-600 mg/kg, and mice received doses of 19-300 mg/kg per day. One female rat at 38 mg/kg and one female rat at 600 mg/kg died. Weight loss or decreased weight gain was seen at 300 and 600 mg/kg in male and female rats. All male mice at 150 and 300 mg/kg died, and one female mouse at 300 mg/kg died; no weight effects were observed in surviving mice. Dose-related necropsy findings included reddened renal medullae in male rats at 600 mg/kg and in male mice at 150 and 300 mg/kg. Clinical signs seen in high dose groups after dosing were hyperactivity in rats and lethargy in mice. In the 13-week studies, male and female rats received doses of 19-300 mg/kg per day, male mice received doses of 6.25-100 mg/kg per day, and female mice received doses of 25-400 mg/kg per day. Five of 10 male rats and 2/10 female rats at 300 mg/kg died. None of the mice died. Final body weights of male and female rats at 150 and 300 mg/kg were lower than those of vehicle controls (45%-88% of vehicle control weights); final body weights of male mice at 100 mg/kg and female mice at 400 mg/kg were 92% and 94% of those of the vehicle controls. Centrilobular degeneration in the liver and degeneration and necrosis of the kidney were seen in male rats at 300 mg/kg; centrilobular degeneration was seen in female rats at 300 mg/kg; degeneration andnecrosis of the kidney were seen in male mice at 100 mg/kg, and centrilobular degeneration of the liver was seen in female mice at 200 and 400 mg/kg. Two-year studies Survival and body weight Final survival of dosed rats was comparable to that of vehicle controls (male: vehicle control, 28/50; low dose, 36/50; high dose, 28/50; female: 34/50; 27/50; 41/50). Mean body weights of high dose male and female rats were decreased during the last 1.5 years of the study; final mean body weights of high dose male and female rats were 88% and 79% of the vehicle control mean weights. Final mean body weights of low dose male and female rats were comparable to those of the vehicle controls. Final survival of dosed male mice was comparable to that of the vehicle controls (34/50; 32/50; 42/50). At week 84, survival of female mice was greater than 50% in all dose groups. After week 84, survival of dosed and vehicle control female mice was reduced (final survival: 26/50; 13/50; 15/50), and this decreased survival was associated with ovarian abscesses (8/50; 19/47; 18/49). The final mean body weight of high dose male mice was 95% that of the vehicle controls; the final mean body weight of low dose male mice was comparable to that of the vehicle controls. Mean body weights of the high dose female mice were decreased during the last 1.5 years of the study; the final mean body weight was 75% that of the vehicle controls. The final mean body weight of the low dose female mice was 91% that of the vehicle controls. Nonneoplastic effects Compound-related nonneoplastic lesions included cytomegaly and tubular cell hyperplasia of the kidney and necrosis and fatty metamorphosis of the liver in male rats; eosinophilic cytoplasmic change, clear cell change, focal cellular change, and fatty metamorphosis of the liver and tubular cell hyperplasia of the kidney in female rats; fatty metamorphosisof the liver, renal cytomegaly, and follicular cell hyperplasia of the thyroid gland in male mice; and follicular cell hyperplasia of the thyroid gland in female mice. Neoplastic effects Bromodichloromethane caused compound-related increases in the incidences of neoplasms of the large intestine and kidney in male and female rats, the kidney in male mice, and the liver in female mice, as shown in the table (see page 5 of the Technical Report). The neoplasms of the large intestine and kidney are uncommon tumors in F344/N rats and B6C3F1 mice. Administration of bromodichloromethane was also associated with a decrease in the tumors of the adrenal glands in male rats, the pituitary and mammary glands in female rats, and the pituitary gland in female mice. Data audit An audit of the experimental data was conducted for the 2-year toxicology and carcinogenesis studies of bromodichloromethane. No discrepancies were found that influenced the final interpretations of the results of these studies. Conclusions Under the conditions of these 2-year gavage studies, there was clear evidence of carcinogenic activity for male and female F344/N rats and B6C3F1 mice as shown by increased incidences of tubular cell adenomas and adenocarcinomas in the kidney and adenocarcinomas and adenomatous polyps in the large intestine in male and female rats, increased incidences of tubular cell adenomas and adenocarcinomas in the kidney of male mice, and increased incidences of hepatocellular adenomas and carcinomas in female mice.

Abstract  We developed a method to analyze airborne lead concentrations in the field. It was a modification of the colorimetric method using the reaction between 4(2-pyridylazo)-resorcinol (PAR) and lead with cyanex302 in an acid medium to reduce interfering metals. The lead concentration was detected with a photometer made in Thailand. The developed method uses an impinger containing 1% nitric acid solution as an absorbing agent to collect airborne lead at a flow rate of less than or equal to one liter/minute. Cyanex302 solution in toluene was used to extract metals from the samples and 0.1M nitric acid was used to extract just lead. The lead solution was reacted in 0.5 ml of 0.03% PAR solution, with 1 ml ammonium chloride buffer; the absorption of this solution was measured by a photometer. The results show the limit of detection (LOD) was 0.01 mg/l. The limit of quantification (LOQ) was 0.03 mg/l. The percent recovery of the lead concentrations of 0.05 - 3.0 mg/l was 94.0 to 103.5%. The precision presented as %CV ranged from 0.65 to 10.27%. Lead concentration in a lead smelting factory detected by this method was not significantly different from that detected by the NIOSH method: 7,303 at a 95% confidence level.

Abstract  A novel fluorescent sensor 4((E)-(N-(rhodamine-6G)lactam-ethylenediamineimino)methyl)benzene-1,3-diol (1), which has a unique spirolactam ring formation, show a reversible, selective, and sensitive fluorescence enhancement response to Cu(II) at biological pH value for practical use. Also, the selectivity of this system for Cu(II) over other metal ions is remarkably high, and its sensitivity is below 2 ppb in methanol solutions. Furthermore, its high cell permeability grants the access to employ 1 as Cu(II) detector in living cells. (C) 2010 Elsevier B.V. All rights reserved.

Abstract  The title compound [systematic name: 5,11,17,23-tetramethyl-2,8,14,16-tetrakis(2-phenylethyl) pentacyclo[19.3.1.1(3,7).1(9,13).-1(15,19)] octacosa-1(25),3,5,7(28), 9,11,13 (27), 15,17,19(26), 21,23-dodecaene- 4,6,10,12,16,18,22,24-octol methanol pentasolvate 0.10-hydrate], C64H64O8 center dot 5CH(4)O center dot 0.103H(2)O, was synthesized as a new synthetic intermediate for resorcin[4] arene cavitand formation. The structure displays extensive O-H center dot center dot center dot O intra- and intermolecular hydrogen bonding.

Abstract  Trichosporon cutaneum R57 is known as effective biodegradant able to utilize and thus remove a number of toxic aromatic compounds from the environment. In the present study, the dynamics of the processes of degradation of monohydoxyl derivatives of phenol (resorcinol, catechol and hydroquinone) in concentrations up to 1.6 g/l were investigated and inhibitory constants (k(i)) of these compounds were determined 0.58, 0.55, and 0.6 g/l correspondingly. The biodegradation of significantly more toxic aromatic compounds 2,6- dinitrophenol (k(i) = 0. 13 g/l), alpha-methylstyrene (k(i) = 0.25 g/l) and acetophenone (k(i) = 0. 15 g/l) was also described. Based on summarized qualitative and quantitative data and the ""if-then"" rules developed, a fuzzy model was designed to describe the processes despite the degree of toxicity and concentration of the aromatic compounds. The output linguistic variables ""normal"", ""check"" and ""attention"" were defined, which determine further measures for improvement of process quality. The model suggested provides opportunity for early estimation of the biodegradation process quality. (C) 2007 Elsevier B.V. All rights reserved.

Abstract  Talc ore may contain several other minerals including calcite, dolomite, magnesite, tremolite, anthophyllite, antigorite, quartz, pyrophyllite, micas, or chlorites. Talc products are sold in a multitude of grades which have physical or functional characteristics especially suited for particular applications, so occupational and consumer exposures to talc are complex. Epidemiology studies have suggested an association between non-fibrous talc and lung cancer risk. Talc was nominated by the National Institute of Occupational Safety and Health (NIOSH) for study by the NTP because of widespread human exposure and because of the lack of adequate information on its chronic toxicity and potential carcinogenicity. Toxicology and carcinogenicity studies of talc (non-asbestiform, cosmetic grade), a finely powdered hydrous magnesium silicate, were conducted by exposing groups of F344/N rats to aerosols for 6 hours per day, 5 days per week for up to 113 weeks (males) or 122 weeks (females). Groups of B6C3F1 mice were exposed similarly for up to 104 weeks. Lifetime study in rats Groups of 49 or 50 male and 50 female rats were exposed to aerosols of 0, 6, or 18 mg/m3 talc until mortality in any exposure group reached 80% (113 weeks for males and 122 weeks for females). These exposures were selected based on 4-week inhalation studies of the terminal lung talc burden in F344/N rats; concentrations greater than 18 mg/m3 were expected to overwhelm lung clearance mechanisms and impair lung function. These exposure concentrations provided a dose equivalent of 0, 2.8, or 8.4 mg/kg per day for male rats and 0, 3.2, or 9.6 mg/kg per day for female rats. In a special study, additional groups of 22 male and 22 female rats were similarly exposed and examined for interim pathology evaluations or pulmonary function tests after 6, 11, 18, and 24 months and lung biochemistry and cytology studies after 24 months. The talc aerosols had a median mass aerodynamic diameter of 2.7 mm in the 6 mg/m3 chamber and a median diameter of 3.2 mm in the 18 mg/m3 chamber, with geometric standard deviations of 1.9 mm. However, there was a 7-week period beginning at study week 11 during which the chamber concentration for the 18 mg/m3 rats varied from approximately 30 to 40 mg/m3 because of difficulties with the aerosol concentration monitoring system. Further, there was a 12-week period beginning at approximately week 70 during which there were difficulties in generating the talc aerosol, and the chamber concentrations for rats and mice were substantially lower than the target concentrations. Survival, body weights, and clinical findings The survival of male and female rats exposed to talc was similar to that of the controls. Mean body weights of rats exposed to 18 mg/m3 were slightly lower than those of controls after week 65. No clinical findings were attributed to talc exposure. Pathology findings Absolute and relative lung weights of male rats exposed to 18 mg/m3 were significantly greater than those of controls at the 6-, 11-, and 18-month interim evaluations and at the end of the lifetime study, while those of female rats exposed to 18 mg/m3 were significantly greater at the 11-, 18-, and 24-month interim evaluations and at the end of the lifetime study. Inhalation exposure of rats to talc produced a spectrum of inflammatory, reparative, and proliferative processes in the lungs. Granulomatous inflammation occurred in nearly all exposed rats and the severity increased with exposure duration and concentration. Hyperplasia of the alveolar epithelium and interstitial fibrosis occurred in or near foci of inflammation in many exposed rats, while squamous metaplasia of the alveolar epithelium and squamous cysts were also occasionally seen. Accumulations of macrophages (histiocytes), most containing talc particles, were found in the peribronchial lymphoid tissue of the lung and in the bronchial and mediastinal Iymph nodes. In female rats, the incidences of alveolar/bronchiolar adenoma, carcinoma, and adenoma or carcinoma (combined) in the 18 mg/m3 group were significantly greater than those of controls. The incidences of pulmonary neoplasms in exposed male rats were similar to those in controls. Minor alterations attributed to talc exposure were also observed in the upper respiratory tract. Hyperplasia of the respiratory epithelium of the nasal mucosa in males and accumulation of cytoplasmic, eosinophilic droplets in the nasal mucosal epithelium in male and female rats occurred with a concentration-related increased incidence in the exposed groups. Adrenal medulla pheochromocytomas [benign, malignant, or complex (combined)] occurred with a significant positive trend in male and female rats, and the incidences in the 18 mg/m3 groups were significantly greater than those of controls. Although adrenal medulla hyperplasia occurred with similar frequency among exposed and control females, the incidences of hyperplasia in exposed males were significantly lower than in controls. Lung talc burden Lung talc burdens of male and female rats exposed to 6 mg/m3 were similar and increased progressively from 6 to 24 months. Lung talc burdens of females exposed to 18 mg/m3 also increased progressively from 6 to 24 months, while those of males exposed to 18 mg/m3 remained about the same after 18 months. Lung burdens were generally proportional to exposure concentration at each interim evaluation. Pulmonary function, bronchoalveolar lavage, and lung biochemistry In exposed male and female rats there was a concentration-related impairment of respiratory function which increased in severity with increasing exposure duration. The impairment was characterized by reductions in lung volume (total lung capacity, vital capacity, and forced vital capacity), lung compliance, gas exchange efficiency (carbon monoxide diffusing capacity), and nonuniform intrapulmonary gas distribution. After 24 months, males exposed to 6 mg/m3 talc had a significant increase in beta-glucuronidase and polymorphonuclear leukocytes; males exposed 18 mg/m3 had significant increases in b -glucuronidase, lactate dehydrogenase, alkaline phosphatase, and total protein in bronchoalveolar lavage fluid. All exposed females had significantly increased a-glucuronidase, lactate dehydrogenase, alkaline phosphatase, total protein, and polymorphonuclear leukocytes; 18 mg/m3 females also had significantly increased glutathione reductase. Viability and phagocytic activity of macrophages recovered from lavage fluid were not affected by talc exposure. Total lung collagen was significantly increased in rats at both exposure concentrations after 24 months, while collagenous peptides in lavage fluid and the percentages of newly synthesized protein from females, but not males, were also significantly increased at the 6 or 18 mg/m3 levels. In addition, lung proteinase activity, primarily cathepsin D-like activity, was significantly greater in exposed males and females. Rats exposed to talc also had significant increases in collagenous peptides and acid proteinase in lung homogenates. Two-year study in mice Groups of 47 to 49 male and 48 to 50 female mice were exposed to aerosols containing 0, 6, or 18 mg/m3 talc for up to 104 weeks. These exposures were selected based on 4-week inhalation studies of the terminal lung talc burden in B6C3F1 mice; concentrations greater than 18 mg/m3 were expected to overwhelm lung clearance mechanisms and impair lung function. These exposure concentrations provide a dose equivalent of 0, 2, or 6 mg/kg per day for male mice and 0, 1.3, or 3.9 mg/kg per day for female mice. In a special study, additional groups of 39 or 40 male and 39 or 40 female mice similarly exposed were examined for interim pathology evaluations, lung biochemistry, and cytology studies after 6, 12, and 18 months of exposure. The talc aerosols had a median mass aerodynamic diameter of 3.3 mm with a geometric standard deviation of 1.9 mm in the 6 mg/m3 chamber, and a median diameter of 3.6 mm with a geometric standard deviation of 2.0 mm in the 18 mg/m3 chamber. Further, there was a 12-week period beginning at approximately week 70 during which there were difficulties in generating the talc aerosol, and the chamber concentrations for rats and mice were substantially lower than the target concentrations. Survival, body weights, and clinical findings Survival and final mean body weights of male and female mice exposed to talc were similar to those of the controls. There were no clinical findings attributed to talc exposure. Pathology findings Inhalation exposure of mice to talc was associated with chronic active inflammation and the accumulation of macrophages in the lung. In contrast to rats, hyperplasia of the alveolar epithelium, squamous metaplasia, or interstitial fibrosis were not associated with the inflammatory response in mice, and the incidences of pulmonary neoplasms in exposed and control groups of mice were similar. Accumulations of macrophages (histiocytes) containing talc particles were also present in the bronchial Iymph node. In the upper respiratory tract, cytoplasmic alteration, consisting of the accumulation of cytoplasmic eosinophilic droplets in the nasal mucosal epithelium, occurred with a concentration-related increased incidence in exposed male and female mice. Lung talc burden Lung talc burdens of mice exposed to 6 mg/m3 were similar between males and females and increased progressively from 6 to 24 months, except for males at 18 months. The lung talc burdens of mice exposed to 18 mg/m3 were also similar between the sexes at each interim evaluation. Although the talc burdens of males and females increased substantially from 6 to 24 months, the values at 12 and 18 months were similar. Generally, lung burdens of mice exposed to 18 mg/m3 were disproportionately greater than those of mice exposed to 6 mg/m3, suggesting that clearance of talc from the lung was impaired, or impaired to a greater extent, in mice exposed to 18 mg/m3 than in mice exposed to 6 mg/m3. Bronchoalveolar lavage and lung biochemistry Increases in total protein, beta-glucuronidase, lactate dehydrogenase, glutathione reductase, total nucleated cells, and polymorphonuclear leukocytes in bronchoalveolar lavage fluid were observed primarily in mice exposed to 18 mg/m3, although some parameters were also increased in mice exposed to 6 mg/m3. The amount of collagenous peptides in lavage fluid and total lung collagen were increased in male and female mice exposed to 18 mg/m3. Acid proteinase activity, principally cathepsin D-like activity, of lung homogenate supernatant fluid was also significantly increased in mice at the 18 mg/m3 exposure concentration. Conclusions Under the conditions of these inhalation studies, there was some evidence of carcinogenic activity of talc in male F344/N rats based on an increased incidence of benign or malignant pheochromocytomas of the adrenal gland. There was clear evidence of carcinogenic activity of talc in female F344/N rats based on increased incidences of alveolar/bronchiolar adenomas and carcinomas of the lung and benign or malignant pheochromocytomas of the adrenal gland. There was no evidence of carcinogenic activity of talc in male or female B6C3F1 mice exposed to 6 or 18 mg/m3. The principal toxic lesions associated with inhalation exposure to the same concentrations of talc in rats included chronic granulomatous inflammation, alveolar epithelial hyperplasia, squamous metaplasia and squamous cysts, and interstitial fibrosis of the lung. These lesions were accompanied by impaired pulmonary function characterized primarily by reduced lung volumes, reduced dynamic and/or quasistatic lung compliance, reduced gas exchange efficiency, and nonuniform intrapulmonary gas distribution. In mice, inhalation exposure to talc produced chronic inflammation of the lung with the accumulation of alveolar macrophages.

Abstract  Singularities of the rhodium trichloride reaction with calix[4]resorcinol functionalized with CH2N center dot (CH3)(2) groups in ethanol on the upper rim of the molecule, and also of calix[4]resorcinol with ethanol solution of rhodium trichloride saturated with nitrogen monoxide were studied. Neutral complex compounds separated in the solid form were characterized by IR spectroscopy, Raman spectroscopy, H-1 NMR, ESR, X-ray electron spectroscopy, electronic spectroscopy, and conductometry. Quantum-chemical calculations were performed on the basis of the density functional method in order to determine the geometric structure and energy characteristics of the complex compound and the zwitter-ion form of the ligand.

Abstract  New carbon aerogels have been prepared from urea-branched phenol-resorcinol-formaldehyde resin. Such material, called ""blue glue"" and used as cold-set adhesive for wood, has been modified in order to obtain highly porous organic gels. The latter were prepared at different pH (5, 7 and 9), dried with supercritical methanol, and carbonised at two different heating rates (2.5 and 5 degrees C min(-1)). FTIR analysis confirmed the expected chemical structure of the gel, and GC-MS analysis of the solvent condensed after supercritical drying suggested a slight chemical degradation of the gels during the drying process. However, low-density (0.15-0.31 g cm(-3)), monolithic, carbon gels could be successfully derived from these materials, having high BET surface areas (900-1300 m(2) g(-1)) and high mesopore fractions (60-80%). These ranges of values originate from the conditions tested for preparing the materials. Such carbon aerogels are two times cheaper than their traditional resorcinol- formaldehyde-based counterparts and present similar, if not more developed, porous structures. (C) 2012 Elsevier Inc. All rights reserved.