bluuebunny/crossref_metadata_2025 huggingface dataset:
Receptor‐operated Ca2+ entry mediated by TRPC3/TRPC6 proteins in rat prostate smooth muscle (PS1) cell line
Authors: Thebault S. , Zholos A. , Enfissi A. , Slomianny C. , Dewailly E. , Roudbaraki M. , Parys J. , Prevarskaya Natalia
Published: January 2005

Prostate smooth muscle cells predominantly express α1‐adrenoceptors (α1‐AR). α1‐AR antagonists induce prostate smooth muscle relaxation and therefore they are useful therapeutic compounds for the treatment of benign prostatic hyperplasia symptoms. However, the Ca2+ entry pathways associated with the activation of α1‐AR in the prostate have yet to be elucidated. In many cell types, mammalian homologues of transient receptor potential (TRP) genes, first identified in Drosophila, encode TRPC (canonical TRP) proteins. They function as receptor‐operated channels (ROCs) which are involved in various physiological processes such as contraction, proliferation, apoptosis, and differentiation. To date, the expression and function of TRPC channels have not been studied in prostate smooth muscle. In fura‐2 loaded PS1 (a prostate smooth muscle cell line) which express endogenous α1A‐ARs, α‐agonists epinephrine (EPI), and phenylephrine (PHE) induced Ca2+ influx which depended on the extracellular Ca2+ and PLC activation but was independent of PKC activation. Thus, we have tested two membrane‐permeable analogues of diacylglycerol (DAG), oleoyl‐acyl‐sn‐glycerol (OAG) and 1,2‐dioctanoyl‐sn‐glycerol (DOG). They initiated Ca2+ influx whose properties were similar to those induced by the α‐agonists. Sensitivity to 2‐aminoethyl diphenylborate (2‐APB), SKF‐96365 and flufenamate implies that Ca2+‐permeable channels mediated both α‐agonist‐ and OAG‐evoked Ca2+ influx. Following the sarcoplasmic reticulum (SR) Ca2+ store depletion by thapsigargin (Tg), a SERCA inhibitor, OAG and PHE were both still able to activate Ca2+ influx. However, OAG failed to enhance Ca2+ influx when added in the presence of an α‐agonist. RT‐PCR and Western blotting performed on PS1 cells revealed the presence of mRNAs and the corresponding TRPC3 and TRPC6 proteins. Experiments using an antisense strategy showed that both α‐agonist‐ and OAG‐induced Ca2+ influx required TRPC3 and TRPC6, whereas the Tg‐activated (“capacitative”) Ca2+ entry involved only TRPC3 encoded protein. It may be thus concluded that PS1 cells express TRPC3 and TRPC6 proteins which function as receptor‐ and store‐operated Ca2+ entry pathways. © 2005 Wiley‐Liss, Inc.
Kinetics of hydrogenation of 4‐chloro‐2‐nitrophenol catalyzed by Pt/carbon catalyst
Authors: Halligudi S B , Khaire Surekha S
Published: January 2005

Hydrogenation of 4‐chloro‐2‐nitrophenol (CNP) was carried out at moderate hydrogen pressures, 7–28 atm, and temperatures in the range 298–313 K using Pt/carbon and Pd/γ‐Al2O3 as catalysts in a stirred pressure reactor. Hydrogenation of CNP under the above conditions gave 4‐chloro‐2‐aminophenol (CAP). Dechlorination to form 2‐aminophenol and 2‐nitrophenol is observed when hydrogenation of CNP is carried out above 338 K, particularly with Pd/γ‐Al2O3 catalyst. Among the catalysts tested, 1%Pt/C was found to be an effective catalyst for the hydrogenation of CNP to form CAP, exclusively. To confirm the absence of gas–liquid mass transfer effects on the reaction, the effect of stirring speed (200–1000 rpm) and catalyst loading (0.02–0.16 g) on the initial reaction rate at maximum temperature 310 K and substrate concentration (0.25 mole) were thoroughly studied. The kinetics of hydrogenation of CNP carried out using 1%Pt/C indicated that the initial rates of hydrogenation had first order dependence with respect to substrate, catalyst and hydrogen pressure in the range of concentrations varied. From the Arrhenius plot of ln rate vs 1000/T, an apparent activation energy of 22 kJ mol−1 was estimated.

© 2001 Society of Chemical Industry
Minimum fluidization velocity and gas holdup in gas–liquid–solid fluidized bed reactors
Authors: Ramesh K , Murugesan T
Published: January 2005

Experiments were performed to study the hydrodynamics of a cocurrent three‐phase fluidized bed with liquid as continuous phase. Based on the 209 experimental data (with four liquid systems and five different particles) along with 115 literature data from six different sources on minimum fluidization velocity, a unique correlation for the estimation of minimum fluidization velocity in two‐phase (ug = 0) as well as in three‐phase systems is developed. A data bank consisting of 1420 experimental measurements for the fractional gas phase holdup data with a wide range of variables is used for developing empirical correlations. Separate correlations are developed for two flow regimes observed in this present work. The proposed correlations are more accurate and simpler to use.

© 2002 Society of Chemical Industry
Biotransformation of benzaldehyde to L‐phenylacetylcarbinol (L‐PAC) by Torulaspora delbrueckii and conversion to ephedrine by microwave radiation
Authors: Shukla Vilas B , Madyar Virendra R , Khadilkar Bhushan M , Kulkarni Pushpa R
Published: January 2005

In a 5 dm3 stirred tank reactor, bioconversion of 30 g benzaldehyde by cells of Torulaspora delbrueckii yielded 22.9 g of pure L‐phenylacetylcarbinol (L‐PAC). Facile functional group transformation of 4.5 g of L‐PAC to 2‐(methylimino)‐1‐phenyl‐1‐propanol by exposure to microwave irradiation for 9 min resulted in 2.48 g of product. Conversion of 4.8 g of 2‐(methylimino)‐1‐phenyl‐1‐propanol to 3.11 g of ephedrine was achieved by exposure to microwaves in a reaction time of 10 min. The identity of all the products was confirmed by 1H NMR and FT‐IR analysis.

© 2002 Society of Chemical Industry
Adsorption of colour from a bleach plant effluent using biomass and cell wall fractions from Rhizomucor pusillus
Authors: Driessel Brian van , Christov Lew
Published: January 2005

Relatively high decolourisation of bleach plant effluent (41%–48%) could be attained in short treatment times using biomass of Rhizomucor pusillus, a mucoralean fungus. Cell wall fractions (alkali‐resistant, residual and chitosan fractions) extracted from the R pusillus biomass appeared to be mainly responsible for the adsorption of chromophores from bleach plant effluent by this fungus. The alkali‐resistant fraction removed 34% of the colour from bleach plant effluent. Although the residual and chitosan fractions represented only about 12% of the total dry biomass, they removed more colour from bleach plant effluent (41%) than did the intact biomass (39%). The chitosan and residual cell wall fractions, mainly composed of chitin and/or chitosan, seem to be involved in the mechanism of colour removal from bleach plant effluent by R pusillus.

© 2002 Society of Chemical Industry
Production of androstenedione using mutants of Mycobacterium sp
Authors: Egorova Olga V , Gulevskaya Seraphima A , Puntus Irina F , Filonov Andrey E , Donova Marina V
Published: January 2005

Mycobacterium sp VKM Ac‐1815D strain was able to cleave sterol side chain giving androstenedione (AD) as a major product with a molar yield of 63–68%. Clones having altered resistance to antibacterial agents were selected. After treatment with ethyl methane sulfonate or mitomycin C, mutants were obtained that retained the ability to produce AD from sitosterol with molar yields of 70–75%. A mutant strain able to effectively reduce 3,17‐diketosteroids at C‐17 was selected. The 17β‐hydroxy steroid dehydrogenase activity of its crude extract was twice as high as that found for the parent organism. The approach offers the possibility of obtaining improved and labelled biocatalysts for AD or testosterone production from sterols.

© 2002 Society of Chemical Industry
Treatment of wastewater containing dyes used in the Syrian textile industry
Authors: El‐Kadri Saleh , Dabbit Ousama , Kakhia Hassan
Published: January 2005

Three types of wastewater, from commercial dyeings containing reactive, disperse and direct dyes were treated using an organic coagulant at pH 5.5 as a first step, with stirring for 5 min. The second step was oxidation by Fenton's reagent (hydrogen peroxide and iron(II) sulfate) at pH 2.5–3 for 30 min. The pH of the solution was then raised to 7.5–8 where coagulation by iron hydroxide took place over 20 min. Finally, sand filtration was performed. The percentage of color removal from treated wastewater was more than 99.00% and the percentage decrease in COD was more than 96.00%.

© 2002 Society of Chemical Industry
Advanced oxidation with ozone of 1,3,6‐naphthalenetrisulfonic acid in aqueous solution
Authors: Sánchez‐Polo M , Rivera‐Utrilla J , Zaror C A
Published: January 2005

The kinetics of oxidation with ozone of 1,3,6‐naphthalenetrisulfonic acid was analysed by studying the influence of different experimental parameters such as the concentration oftert‐butyl alcohol (2‐methyl‐2‐propanol), initial concentration of the acid, pH, and temperature. The rate constant of the direct reaction at 25 °C was calculated (kD = 6.72 M−1s−1). The constant of the free radical reaction was determined with the competitive kinetics method, using sodium 4‐chlorobenzoate as reference compound, obtaining a value ofkOH = 3.7 × 109 M−1s−1. It was demonstrated that even at very acid pH values, 80% of the 1,3,6‐naphthalenetrisulfonic acid was degraded by free radical reactions, so that the ozonation of this acid may be considered an advanced oxidation process.

© 2002 Society of Chemical Industry
Study of operating variables in the transformation of aqueous ethanol into hydrocarbons on an HZSM‐5 zeolite
Authors: Aguayo Andres T , Gayubo Ana G , Tarrío Ana M , Atutxa Alaitz , Bilbao Javier
Published: January 2005

With the aim of determining the possibilities of directly upgrading the liquid obtained from carbohydrate fermentation, the effect of operating conditions (temperature, space time, water content in the feed) has been studied in the catalytic transformation of aqueous ethanol into hydrocarbons on an HZSM‐5 zeolite in an isothermal fixed bed reactor. Special attention has been paid to the effect of water content on the yield, product distribution and catalyst deactivation. Although deactivation by coke decreases as the water content is increased, this content must be limited at 450 °C and higher temperatures in order to avoid irreversible deactivation of the catalyst by dealumination.

© 2002 Society of Chemical Industry
Penicillin acylase release from Escherichia coli cells by mechanical cell disruption and permeabilization
Authors: Fonseca L P , Cabral J M S
Published: January 2005

The release of Penicillin acylase from Escherichia coli cells through mechanical cell disruption using high‐pressure homogenization and sonication was studied. From these cell disruption processes, the enzyme activity was totally released although with low specific activities, 0.1–0.3 IU(mg prot)−1. Intracellular total soluble protein release was quantified and modelled by a first order kinetic model. The effect of the driving force for each mechanical method, namely acoustic power input and homogenization pressure, on the respective kinetic disruption constants was also analysed. The release of Penicillin acylase by cell permeabilization using osmotic shock was also evaluated. The effects of cell concentration, penicillin acylase activity in E coli cells, type of buffer, pH, hypertonic solution composition, temperature and time used for osmotic shock were evaluated. Using cold osmotic shock, highly selective penicillin acylase release was attained with specific enzyme activities of about 4 IU(mg prot)−1 and enzyme activity release yields higher than 90%. The high purity of the penicillin acylase was a consequence of the optimized differential enzyme release method which was validated by SDS gel electrophoresis.

© 2002 Society of Chemical Industry
Effect of input power and feeding concentration on MTBE decomposition using an RF plasma reactor
Authors: Hsieh Lien‐Te , Fang Guor‐Cheng , Yang Hsi‐Hsien , Wang Ya‐Fen , Tsao Meng‐Chun
Published: January 2005

The toxicology of the widely used oxygenated fuel additive methyl tert‐butyl ether (MTBE) has recently attracted considerable interest in the public sector. In this study, a radio‐frequency (RF) plasma reactor was used to decompose MTBE gas. The effects of two important plasma operational parameters – including power consumption per unit volume of the plasma (WD, W cm−3) and MTBE feeding concentration (CMTBE, %) – for MTBE decomposition were investigated in detail. The results show that the MTBE decomposition efficiency (ηMTBE) increases with increasing WD and with decreasing CMTBE. In this study, the results reveal that, in the MTBE/Ar plasma, the ηMTBE was over 99.9%, which occurred at the conditions of for WD = 0.96W cm−3, CMTBE = 3%, 20 Torr of operational pressure and a 100 cm3 · min−1 total gas flow rate. In particular, the effects of WD and CMTBE for the species detected in the effluent gas stream are carefully discussed. In addition, the deposition problem which occurred in the reactor was examined by means of Scanning Electron Microscopy (SEM).

© 2002 Society of Chemical Industry
Extraction of iron(III) from acidic sulfate solutions with bis(2‐ethylhexyl)phosphoric acid in PENRECO® 170 ES, a new friendly diluent
Authors: Suárez Claudio , Ahumada Eduardo , Orellana Fabián , Hein Hans , Cote Gerard , Lizama Hernan
Published: January 2005

The extraction of iron(III) from acidic sulfate solutions by bis(2‐ethylhexyl)phosphoric acid (HDEHP) is investigated by using PENRECO® 170 ES as a diluent. PENRECO® 170 ES is new diluent which offers advantages such as improved solvency power, more complete phase disengagement and reduced losses in aqueous streams, with reductions of over 50% in diluent usage after 1 year, compared with conventional paraffinic diluents. The chemical analyses performed in the present work suggest that such properties arise, at least in part, from the presence of a series of hydrophobic branched alcohols in its composition (at least 0.6 mol dm−3). In spite of the solvation effects due to these alcohols, HDEHP is dimeric in this diluent and, in the presence of an excess of HDEHP, the extraction of iron(III) takes place according to the classical equation: $Fe^{3+} + 3\overline{H_2L_2} \Leftrightarrow \overline{FeL_3 \cdot 3HL} + 3H^+$ with Kex = 105.7 ± 0.2 (at I  = 1 mol dm−3). Such a value of Kex is similar to that reported for pure hexane, which shows that the presence of long chain alcohols in PENRECO® 170 ES has no perceptible influence on the thermodynamics of iron(III) extraction by HDEHP. The extraction of iron(III) by HDEHP in PENRECO® 170 ES is slightly more rapid than in kerosene, which indicates that the molecules of alcohols constituting PENRECO® 170 ES have no negative effect on the kinetics of metal extraction although they compete with the extractant molecules for adsorption at the liquid–liquid interface. Stripping of iron(III) from loaded organic solutions by sulfuric acid is easy and rapid (95% equilibrium reached within 2 min) when HDEHP is used at moderate concentrations (typically 0.1 mol dm−3). At higher HDEHP concentrations, stripping is difficult and incomplete, as found previously with other diluents. Thus, PENRECO® 170 ES is interesting in its ability to overcome some of the physical problems encountered in liquid–liquid operations, but its use does not modify significantly the chemistry of iron(III) extraction by HDEHP.

© 2002 Society of Chemical Industry
Equilibrium and kinetic studies of the extraction of chelated copper(II) anions with Aliquat 336
Authors: Lin Su‐Hsia , Kao Hsiang‐Chien , Huang Shih‐Hung , Juang Ruey‐Shin
Published: January 2005

The equilibrium and kinetics of solvent extraction of Cu2+ from aqueous solutions containing equimolar EDTA with Aliquat 336 in n‐decanol and kerosene at 298 K were investigated. The concentrations of Cu2+ (8–50 mol m−3), Cl− (5–60 mol m−3), and Aliquat 336 (20–100 mol m−3) were varied. A semi‐empirical model with three parameters was proposed to describe the equilibrium behavior, in which the non‐idealities in both aqueous and organic phases were considered. Over the ranges studied, the model agreed reasonably well with the experimental data (standard deviation, 15%). The forward and backward reaction rate constants were determined as (5.31 ± 0.16)×10−6 m9/4 mol−3/4 s−1 and (2.62 ± 0.09)×10−7 s−1, respectively, at 298 K. An interfacial reaction mechanism was proposed, which revealed that the reaction between the chelated anions and trimeric amine molecules at the interface was rate limiting. The derived rate laws were consistent with the experimental results.

© 2002 Society of Chemical Industry
Immobilisation of different Candida rugosa lipases by adsorption onto polypropylene powder: application to chiral synthesis of ibuprofen and trans‐2‐phenyl‐1‐cyclohexanol esters
Authors: López Neus , Pérez Rafael , Vázquez Felícitas , Valero Francisco , Sánchez Antoni
Published: January 2005

Candida rugosa lipases (CRLs) were immobilised by adsorption onto a commercial polypropylene powder EP100™. Two commercial CRLs from Sigma and Amano were used together with two CRLs obtained by fed‐batch fermentation using oleic acid as a carbon source (UAB‐CRL). Significant differences were observed in the isotherm adsorption patterns for the commercial and fermented lipases, probably caused by differences in their polysaccharide content. The commercial lipases showed a classical Langmuir adsorption pattern, whereas fed‐batch produced lipases with high polysaccharide content tended to conform to a BET multilayer adsorption equation. Immobilised CRLs also showed different behaviour in the resolution of two interesting pharmaceutical products: ibuprofen and trans‐2‐phenyl‐1‐cyclohexanol (TPCH) in the enantioselective esterification reaction in organic media. In the case of ibuprofen, CRLs showed important differences in terms of esterification rate, probably due to diffusional limitation effects caused by the high polysaccharide content present in UAB‐CRLs. In the case of TPCH, however, polysaccharide content did not appear to influence the esterification rate. A high enantioselective esterification was observed for all CRLs tested in the resolution of both products.

© 2002 Society of Chemical Industry
Photocatalytic pretreatment of contaminated groundwater for biological nitrification enhancement
Authors: Zhang Zisheng , Anderson William A , Moo‐Young Murray
Published: January 2005

The sequential photocatalytic/biological treatment of a contaminated groundwater from a local industrial site was studied. The ground water contained approximately 100 mg dm−3 ammonia, as well as mg dm−3 levels of nitrification‐inhibiting organics such as chlorobenzene. An existing treatment system uses carbon adsorption pretreatment to remove the nitrification inhibitors before the water is treated in a biological nitrification system. Photocatalysis, using a corrugated plate photoreactor, was studied as an alternative to the carbon adsorption system for inhibitor removal. Photocatalytic pretreatment was found to significantly enhance the extent of biological nitrification. An optimal pretreatment time appeared to exist, since further pretreatment resulted in accumulation of nitrite. Although further study is required, there appears to be a potential for using photocatalysis to remove inhibitors from biological nitrification systems.

© 2002 Society of Chemical Industry
Effectiveness test of alginate‐derived polymeric surfactants
Authors: Kang Hyun‐Ah , Jeon Gyu‐Jong , Lee Moo‐Yeal , Yang Ji‐Won
Published: January 2005

A series of alginate‐derived polymeric surfactants (APSs) with a linear alkyl group (C8, C12, C16) was synthesized by oxidation followed by reductive amination of 2,3‐dialdehydic alginate. The products were characterized by measuring IR spectra, NMR spectra, surface tension and critical micelle concentration (cmc). They were also tested for the solubilization of azobenzene and adsorption of heavy metal. In the case of 40% CHO‐C8 APSs, the lowest interfacial tension value (31.5 m Nm−1) was obtained at the cmc value of 1.35 g dm−3. The dissolving capacity of 40% CHO‐C8 APS towards azobenzene was 27 times greater than that of alginate. The overall cobalt (Co2+) removal efficiency by adsorption using APSs was high compared with that of sodium alginate at pH 3, 5 and 7. Equilibrium aspects of cobalt adsorption onto 10% CHO‐APSs were studied, and the results show that APSs had high equilibrium capacities for cobalt uptake, 115.5 mgg−1.

© 2002 Society of Chemical Industry
Chemical neutralization of acidic wastes using fly ash in Israel
Authors: Polat Mehmet , Lederman Eli , Pelly Ithamar , Cohen Haim
Published: January 2005

Israeli fly ash is highly basic when exposed to water, due to the very low sulfur content allowed in coal imports because of the strict environmental regulations (with respect to SOx emissions). Thus, the fly ash is a potential chemical neutralization/fixation agent for acidic wastes. In this study, coal fly ash has been examined as a neutralization/fixation agent for acidic sludge produced from the regeneration of used engine oils. The initial results show that the fly ash can be used as a very efficient neutralization/fixation agent of the sludge. Furthermore the trace elements and the organic components are efficiently fixed within the fly ash particles. The product can serve as a good aggregate in concrete production. The neutralization and fixation processes are discussed in detail.

© 2002 Society of Chemical Industry
Delignification of Pinus taeda wood chips treated with Ceriporiopsis subvermispora for preparing high‐yield kraft pulps
Authors: Mendonça Régis , Guerra Anderson , Ferraz André
Published: January 2005

Pinus taeda wood chips were treated with the white‐rot fungus Ceriporiopsis subvermispora in 20‐dm3 bioreactors for periods varying from 15 to 90 days. Decayed samples, non‐inoculated controls and extractive‐free wood samples were submitted to kraft pulping using 25% of sulfidity and different active alkali concentrations in the cooking liquor. Cooking reactions were carried out isothermally at 170 °C. Residual lignin contents of pulps prepared from biotreated wood chips were lower than those observed in pulps from the undecayed control. Delignification kinetic studies showed that the initial delignification phase was accelerated and shortened by the fungal pretreatment. At a cooking time fixed before the end of the bulk delignification phase, the fungal pretreatment provided pulps with significantly lower kappa numbers or pulps with a fixed kappa number were obtained by reducing the amount of active alkali added to the liquor. Pulps of kappa 80 were obtained both from the undecayed control cooked with 20.8% of active alkali and from the 15‐day‐biotreated sample cooked with only 15% of active alkali. The biopulping benefits were neither proportional to the extent of the biodelignification nor to the biological removal of some specific wood component. DFRC‐determination (derivatization followed by reductive cleavage) of the amount of aryl–ether linkages in residual lignins of biotreated samples indicated an extensive depolymerization during the initial stages of biodegradation, which suggested that bio‐depolymerized lignin was easily released during the first stages of cooking, resulting in a faster and shorter initial delignification phase.

© 2002 Society of Chemical Industry
Production and recovery of poly‐3‐hydroxybutyrate from Methylobacterium sp V49
Authors: Ghatnekar M S , Pai J S , Ganesh M
Published: January 2005

Bacterial polyesters have shown potential as biodegradable plastics. Microorganisms capable of producing these polyesters from cheaper carbon sources and methods for their efficient recovery are widely studied worldwide. Methylobacterium sp V49, an environmental isolate, was cultivated on a mineral salts medium containing different carbon sources. Maximum accumulation of poly‐3‐hydroxybutyrate (PHB) within the bacterial cell was observed with glucose as the carbon source. Methanol and sugars such as sucrose and lactose also induced PHB accumulation. The effect of C:N ratio on polymer accumulation was studied. Different strategies for the extraction and recovery of the polymer from the cells were compared. A non‐solvent‐based method using a high‐pressure homogenizer in the presence of SDS was found to be the most satisfactory. Maximum recovery of 98% was achieved by homogenizing the cells at 400 kgcm−2 in 5% SDS solution.

© 2002 Society of Chemical Industry
Impact of dissolved wastewater constituents on peroxidase‐catalyzed treatment of phenol
Authors: Wagner Monika , Nicell James A
Published: January 2005

The impact of dissolved wastewater constituents on the treatment of synthetic phenol solutions using horseradish peroxidase (HRP) and hydrogen peroxide was investigated under a variety of reaction conditions. The constituents studied included various inorganic salts, organic compounds and heavy metals. Higher H2O2 doses were required to treat phenol in the presence of sodium sulfite, thiosulfate and sulfide; however, enhanced levels of phenol conversion were achieved once sufficient H2O2 was supplied. Sulfide and cyanide inhibited phenol transformation. The inhibition of sulfide was overcome by supplying sufficient H2O2 to oxidize the sulfide to sulfur. However, increasing the H2O2 dose was ineffective in attempting to overcome the strong inhibiting effect of cyanide. Among the heavy metal ions tested, only Mn(II) substantially inhibited phenol removal when it was present at a concentration of 1 mmol dm−3. The presence of inorganic salts including NaCl, CaCl2, MgCl2, NH4Cl and (NH4)2SO4 reduced phenol conversion as compared with the treatment in distilled‐deionized water. This can be attributed to the increased ionic strength of the solution.

© 2002 Society of Chemical Industry
Removal of cadmium and production of cadmium powder using a continuous undivided electrochemical reactor with a rotating cylinder electrode
Authors: Grau Javier M , Bisang José M
Published: January 2005

The behaviour of a continuous undivided electrochemical reactor with a rotating cylinder electrode under potentiostatic control is examined for the abatement of cadmium from synthetic sodium sulfate solutions with Cd(II) concentrations lower than 500 mg dm−3 at a reactor inlet pH ≅ 7. The process was designed to convert the metal ions in solution to metal powder, which settles to the conical of the reactor and may be removed at intervals as a sludge by opening a drop valve. The effect of applied potential, inlet cadmium concentration, rotation speed and hydrogen evolution as side cathodic reaction on the ‘figures of merit’ of the reactor are analysed. The best results were obtained for cathode potentials in the range from −0.9 V to −1.0 V against the saturated calomel electrode. Therefore, when the rotation speed was 1000 rpm the space time yield and the normalized space velocity were 0.64 ×10−2 mol m−3 s−1 and 0.89 h−1 respectively, while the fractional conversion per pass was 35% with a current efficiency higher than 74%. The surface morphology of the deposits as a function of the process variables is also reported.

© 2002 Society of Chemical Industry
Leaching and electrochemical recovery of copper, lead and tin from scrap printed circuit boards
Authors: Mecucci Andrea , Scott Keith
Published: January 2005

The recovery of copper, lead and tin from scrap printed circuit boards (PCBs) has been achieved using a combination of leaching, electrochemical ion exchange and electrodeposition. A simple aqueous nitric acid stripping solution, with the concentration range of 1–6 mol dm−3, has demonstrated the potential for selective extraction of copper and lead from the PCBs. Precipitation of tin as H2SnO3 (metastannic acid) occurred at acid concentrations above 4 mol dm−3. Preliminary galvanostatic electrolysis from simulated leaching solutions has investigated the feasibility of electrodeposition of copper and lead at different concentrations of HNO3. Cathodic lead deposition, particularly at high electrolyte conditions, resulted in poor current efficiency. This was mainly due to dentritic metal formation and subsequent re‐dissolution. An alternative method investigated for recovering the metal values was the simultaneous electrodeposition of copper at the cathode and lead dioxide at the anode. Electrohydrolysis for acid and base regeneration from the spent nitric acid electrolyte has also been investigated.

© 2002 Society of Chemical Industry
Adsorption of lead(II) from aqueous solution by activated carbon prepared from Eichhornia
Authors: Shekinah P , Kadirvelu K , Kanmani P , Senthilkumar P , Subburam V
Published: January 2005

Activated carbon prepared from Eichhornia was used for the adsorptive removal of Pb(II) from aqueous solution. As the raw material for the preparation of the activated carbon is an aquatic weed, the production of this carbon is expected to be economically feasible. Parameters such as agitation time, metal ion concentration, adsorbent dose and pH were studied. Adsorption equilibrium was reached in 100 min for a solution containing 15 mgdm−3 and 125 min for solutions containing 20 and 25 mgdm−3 Pb(II), respectively. Adsorption parameters were determined using both Langmuir and Freundlich isotherm models. The adsorption capacity was 16.61 mgg−1 at pH 3.0 for particle sizes of 125–180 µm. Pb(II) removal increased as the pH increased from 2 to 4 and remained constant up to pH 10.0. Desorption studies were also carried out with dilute hydrochloric acid to recover both carbon and Pb(II). Quantitative desorption of Pb(II) from carbon indicates that adsorption of metal ion is by ion exchange.

© 2002 Society of Chemical Industry
Application of a carbon sorbent for the removal of cadmium and other heavy metal ions from aqueous solution
Authors: El‐Shafey E I , Cox M , Pichugin A A , Appleton Q
Published: January 2005

Treatment of flax shive with sulfuric acid produces a carbonaceous material that has been used to remove metal ions from aqueous solution. Metal ions including Cd(II), Cu(II), Cr(III), Co(II), Ni(II), Zn(II) and Pb(II) have been investigated for kinetic behaviour and sorption capacities. These metal ions show fast sorption kinetics following a first order rate equation. Cadmium was chosen as representative of these metal ions and a detailed study was carried out. The effect of pH on sorption was studied and it was found that maximum uptake occurred above pH 3–7, sorption was accompanied by release of protons into the solution and a ratio of [H+] released to [Cd2+] sorbed of approximately 2 was found. The sorption capacity showed no significant increase with increase of temperature. The presence of other metal ions such as K+, Na+, Mg2+ and Ca2+ decreases the Cd(II) capacity, indicating competition for the ion exchange sites. Successive sorption of Cd(II) shows that the capacity exceeds the monolayer capacity calculated from the Langmuir equation. Column studies showed good performance over a total of seven cycles of loading/stripping. These studies indicate that the sorption mechanism for these metal ions is related to a reversible ion exchange process on the carbon surface.

© 2002 Society of Chemical Industry
The treatment of binary VOC mixtures by adsorption and oxidation using activated carbon and a palladium catalyst
Authors: Kullavanijaya Emwajee , Cant Noel W , Trimm David L
Published: January 2005

The adsorption of binary thiophene‐containing mixtures on activated carbon and their subsequent desorption and oxidation over a Pd/CeO2/Al2O3 catalyst has been studied as a model for the treatment of dilute VOC streams by intermittent accumulation and combustion. When adsorbed together, cyclohexene and thiophene have similar breakthrough times with little tendency for one to displace the other. However the adsorption of thiophene continues beyond that of diethylamine in mixtures while thiophene is itself displaced by methylmethacrylate. Oxidation of the binary mixtures is controlled by that of thiophene which requires temperatures somewhat above 300 °C for complete removal. Combustion of the other VOCs proceeds in parallel with thiophene although they react at much lower temperatures when alone. Both components of the mixtures can be removed by a system in which the VOCs are accumulated on carbon and then undergo temperature programmed desorption in air onto Pd/CeO2/Al2O3 held at 350 °C. However it is not possible to operate with the adsorbent and catalyst together since desorption then occurs before the catalyst reaches working temperature.

© 2002 Society of Chemical Industry
Ethical issues in biotechnologies and international trade
Authors: Hulse Joseph H
Published: January 2005

Natural and physical sciences are based on determinable facts. What is ethical, as distinct from illegal, is largely a matter of opinion. Scientific and industrial activities related to ancient and modern biotechnologies are among the most critically scrutinised for ethical probity by social activists and journalists. The practices and products of biotechnologies should be judged both deontologically – by motivation and intention, and teleologically – by determinable consequence. Bioethical criteria have been proposed by governments, medical practitioners and philosophers for many centuries. During the past decade, various scientifically competent organisations, national and international, have formulated comprehensive protocols by which to determine effectiveness and safety of novel foods, pharmaceuticals and other biologicals, including those derived from genetically modified organisms. Means and opportunities by which to satisfy the health and nutritional needs of impoverished nations and communities differ significantly from those who enjoy greater affluence. It is distinctly unethical for Europeans and North Americans, whose food and health securities are not at risk, to impose their ethical predilections on poorer nations. Equally reprehensible are the diverse tariff and non‐tariff barriers to equitable international trade, and acts of biopiracy inflicted upon poorer nations. As a wise Asian sage has observed, the planet's resources and scientific ingenuity are sufficient to satisfy everyone's need, but not everyone's greed. Present and predictable world‐wide demand for bioscientists and bioengineers exceeds best estimates of supply. Systematically planned, long‐term investments by governments and bioindustries to generate adequate qualified men and women are urgently needed.

© 2002 Society of Chemical Industry.
Single‐step, multiple retroviral transduction of human T cells
Authors: Abad José Luis , Serrano Fernando , Román Ascensión L. San , Delgado Rafael , Bernad Antonio , González Manuel A.
Published: January 2005

Background

Retroviral transduction of human peripheral blood T cells has considerable potential in the development of gene therapy strategies for immunological disorders. New vectors and experimental procedures have been developed for efficient transduction of several genes into human T cells.

Methods

Bicistronic retroviral vectors encoding distinct cell markers were used for the simultaneous multiple transduction of a human T‐cell line (MT‐2), as well as of human peripheral blood T cells from normal donors. Transduction efficiencies were evaluated by flow cytometry and double‐ and triple‐transduced cells were isolated by fluorescence cell sorting.

Results

Four new bicistronic retroviral vectors were developed that express different gene markers under the control of the internal ribosome entry site (IRES) of the encephalomyocarditis virus. These markers are, respectively, enhanced green fluorescent protein (EGFP), β‐galactosidase, and truncated versions of human nerve growth factor receptor (ΔNGFR) and human growth hormone receptor (ΔGHR). A single 1 h spinoculation infection, performed in the presence of polybrene and using transiently produced amphotropic retroviral particles, was sufficient to obtain transduction efficiencies consistently greater than 50% on human peripheral blood T lymphocytes which had been previously stimulated for 3 days with immobilized anti‐CD3. The transient production of viral particles encoding EGFP, ΔNGFR, and ΔGHR markers in the same viral supernatant has allowed up to three different genes to be introduced simultaneously into human T cells.

Conclusions

This study describes new experimental conditions for efficient single‐step multiple transduction of human primary T lymphocytes. The procedure could be of interest for the development of gene therapy approaches. Copyright © 2002 John Wiley & Sons, Ltd.
Encapsulated cells producing retroviral vectors for in vivo gene transfer
Authors: Saller Robert M. , Indraccolo Stefano , Coppola Vincenzo , Esposito Giovanni , Stange Jan , Mitzner Steffen , Amadori Alberto , Salmons Brian , Günzburg Walter H.
Published: January 2005

Background

Because gene therapy of the future will primarily take an in vivo approach, a number of problems associated with its current implementation exist. Currently, repeated delivery of a vector in vivo is necessary to ensure adequate transfer of the therapeutic gene. This may lead to the development of an immune response against the vector, thus interfering with gene delivery. To circumvent this problem, retroviral vector packaging cells that permanently produce recombinant retroviral vector particles have been encapsulated.

Methods

Vector (pBAG)‐producing amphotropic cells were encapsulated in beads composed of polymerized cellulose sulphate. These capsules were analysed in vitro for expression of the vector construct using X‐gal staining, as well as for the release of particles by performing RT‐PCR from culture supernatant. Infectivity studies were performed in vitro and in vivo. The latter was assayed using histological sections of the microcapsule and the surrounding area stained for β‐galactosidase activity and by RT‐PCR.

Results

In culture, the virus‐producing cells inside the capsules remained viable and released virus into the culture medium for at least 6 weeks. To test whether these capsules, upon implantation into mice, also release vector virions that infect the surrounding cells, two different models were used. In the first, capsules were implanted in the fat pad of the mammary gland of Balb/c mice. The capsules were well tolerated for at least 6 weeks and a self‐limiting inflammatory reaction without any other gross immune response was observed during this period. Furthermore, the virus‐producing cells remained viable. In the second model, SCID mice were immunologically reconstituted by subcutaneous implantation of thymus lobes from MHC‐identical Balb/c newborn mice and gene transfer into lymphoid cells was achieved by retroviral vectors released by co‐implanted capsules.

Conclusion

The implantation of such capsules containing cells that continually produce retroviral vector particles may be of use for in vivo gene therapy strategies. The data presented demonstrate the feasibility of the concept. Copyright © 2002 John Wiley & Sons, Ltd.
Coping with, and cashing in on, international capital volatility
Authors: Bird Graham , Rajan Ramkishen S.
Published: January 2005

The political economy of currency taxation suggests that the idea will receive more support if it can be shown to make a significant contribution to offsetting the perceived inefficiencies of private international capital markets. This paper explores what can be expected from a currency tax in this respect. It shows that there are simple but neglected analytical issues that make such a tax an attractive idea. If the tax is relatively ineffective in helping to avoid financial crises and calming markets, it will be relatively effective at providing the resources necessary to mitigate the aftermath of such events. The paper offers new proposals for using the revenue from currency taxation to finance the operations of the IMF. © 2001 John Wiley & Sons, Ltd.
Defining the category of ‘small’ states
Authors: Crowards Tom
Published: January 2005

There is no widely accepted definition of a small state. Most previous definitions have been based upon arbitrarily chosen cut‐off values of selected criteria. The present study attempts to categorize the size of 190 states according to population, land area and total income. An initial categorization is based upon observation of each series to identify discontinuities in the distributions. Cluster analysis is then employed to identify groups of countries that share similar size‐related characteristics. A classification based on non‐hierarchical cluster analysis is proposed, generating four clusters from equally spaced initial cluster‐centres. On this basis, 79 countries are classified as ‘small’. The reasons for deviation from recent categorizations of small countries are explored, the primary cause being the inclusion of some countries with very low levels of income. Copyright © 2002 John Wiley & Sons, Ltd.
Innovation in finance and movement to client‐centered credit
Authors: Von Pischke J. D.
Published: January 2005

Progression from product‐centred to client‐centered lending is made possible by innovation, which is by definition cost‐reducing. Innovation in finance occurs in three ways: lengthening term structure, reducing transaction costs, and refining valuation processes. Each of these involves risk. The Thesis Statement is consistent with observed market behaviour but may be criticized for insufficient attention to risk as part of the mechanics of the progression it portrays. As is rapidly occurring in the US, personal credit in other countries will move toward being based almost entirely on empirical probability and hence client‐centered as foreseen in the Statement.

In the meantime, the market for money progresses at various speeds from being product‐centered to being client‐centered. When this progression is complete, marketing will be as strategically important as risk management. To the extent that marketing is thought, prematurely, to trump risk management as the key to success, and to the extent meeting client ‘needs’ is viewed as the primary objective, attempts at innovation are likely to fail. When this failure occurs, the social and economic benefits of denying loans will be foregone, hindering development. Questionable projects with problematic sponsors and improper financing will be taken on, limiting growth. Copyright © 2002 John Wiley & Sons, Ltd.
Preparation and a simple one‐step purification of [His1‐mono‐125I‐Tyr10,Nle27]‐hGHRH(1‐32)‐NH2
Authors: Gardi Janos , Krueger James M. , Speth Robert C.
Published: January 2005

A one‐step purification of [His1‐mono‐125I‐Tyr10,Nle27]‐hGHRH(1‐32)‐NH2, prepared using chloramine‐T, by HPLC with isocratic elution is described. The labeled GHRH analog was suitable for GHRH receptor binding assays. Copyright © 2002 John Wiley & Sons, Ltd.
Tritiation of SR141716 by metallation–iodination–reduction: tritium‐proton nOe study
Authors: Seltzman Herbert H. , Ivy Carroll F. , Burgess Jason P. , Wyrick Christopher D. , Burch David F.
Published: January 2005

The central cannabinoid receptor antagonist SR141716, N‐(piperidin‐1‐yl)‐5‐(4‐chlorophenyl)‐1‐(2, 4‐dichlorophenyl)‐4‐methyl‐1H‐pyrazole‐3‐carboxamide, was synthesized from commercially available starting materials. Condensation of an aryl hydrazine with a diketone followed by base promoted isomerization/cyclization of the intermediate anti‐imine gave the pyrazole acid which was converted to the title hydrazide via its acid chloride. Facile iodination via metallation followed by in situ trapping with an iodine source gave a modest yield of the iodinated SR141716. The iodine was selectively reduced with tritium gas and catalyst while retaining the three aryl chlorine atoms in the structure. The tritiated SR141716 exhibited a tritium‐proton nOe both definitively identifying the position of the tritium as well as the sought isomer of the diarylpyrazole. This work provides a direct method for the preparation of preferred iodinated aryl substrates that offer advantages where selectivity and high incorporation in catalytic reduction is sought. Copyright © 2002 John Wiley & Sons, Ltd.
Synthesis of [11C]atipamezole, a potential PET ligand for the α2‐adrenergic receptor in the brain
Authors: Roeda D. , Sipilä H.T. , Bramoullé Y. , Enas J. D. , Vaufrey F. , Dollé F. , Crouzel C.
Published: January 2005

The α2‐adrenergic receptor antagonist atipamezole has been labelled with carbon‐11 using [11C]formaldehyde and 2‐ethyl‐2‐oxoacetylindane. Various routes are proposed for the synthesis of the latter: oxidation of 2‐acetyl‐2‐ethylindane, hydrolysis of 2‐diethoxy‐2‐indane and oxidation of 2‐diazoacetyl‐2‐ethylindane. The average radiochemical yield of [11C]atipamezole was 24% based on [11C]formaldehyde, and the synthesis time, including HPLC purification and formulation, was 45 min. Copyright © 2002 John Wiley & Sons, Ltd.
Synthesis of deuterated‐BCX‐1777, a potent inhibitor of purine nucleoside phosphorylase
Authors: Kezar Hollis S. , Hutchison Tracy L. , Tyler Peter C. , Morris Philip E.
Published: January 2005

BCX‐1777, a novel inhibitor of the enzyme purine nucleoside phosphorylase, mimics the charged ribosyl oxocarbenium ion formed during the transition state of the enzyme‐catalyzed CN bond cleavage of nucleosides. BCX‐1777 is a slow‐onset, tight‐binding inhibitor with a Ki* of 23 pM and is one of the most potent inhibitors known for the enzyme. In support of our BCX‐1777 program, a mass spectrometric assay has been developed utilizing 5′‐[2H]‐BCX‐1777 as an internal standard. The synthesis of 5′‐[2H]‐BCX‐1777 is described in this report. Copyright © 2002 John Wiley & Sons, Ltd.
Synthesis of (±) 3‐(6‐nitro‐2‐quinolinyl)‐[9‐methyl‐11C]‐3,9‐diazabicyclo‐[4.2.1]‐nonane ([11C‐methyl]NS 4194)
Authors: Jensen Svend B. , Bender Dirk , Smith Donald F. , Scheel‐Krüger Jørgen , Nielsen Elsebet Ø. , Olsen Gunnar M. , Peters Dan , Gjedde Albert
Published: January 2005

(±) 3‐(6‐Nitro‐2‐quinolinyl)‐[9‐methyl‐11C]‐3,9‐diazabicyclo‐[4.2.1]‐nonane ([11C‐methyl]NS 4194), a selective serotonin reuptake inhibitor (SSRI), was synthesised within 35 min after end of bombardment with a radiochemical purity >98%. It had a decay‐corrected radiochemical yield of 7% after preparative HPLC, and a specific radioactivity around 37 GBq/μmol (EOS). A typical production starting with 40 GBq [11C]CO2 yielded 800 MBq of radiolabelled [11C‐methyl]NS 4194 in a formulated solution. The synthesis of the precursor to [11C‐methyl]NS 4194, (±) 9‐H‐3‐[6‐nitro‐(2‐quinolinyl)]‐3,9‐diazabicyclo‐[4.2.1]‐nonane, as well as the unlabelled analogue (±) 9‐methyl 3‐[6‐nitro‐(2‐quinolinyl)]‐3,9‐diazabicyclo‐[4.2.1]‐nonane (NS 4194), are also described. Copyright © 2002 John Wiley & Sons, Ltd.
Novel synthesis of [1‐11C]γ‐vinyl‐γ‐aminobutyric acid ([1–11C]GVG) for pharmacokinetic studies of addiction treatment
Authors: Zhang Zongren , Ding Yu‐Shin , Studenov Andrei R. , Gerasimov Madina R. , Ferrieri Richard A.
Published: January 2005

γ‐Vinyl‐γ‐aminobutyric acid (GVG, Vigabatrin®), a suicide inhibitor of GABA‐transaminase (GABA‐T), has been suggested as a new drug for the treatment of substance abuse. In order to better understand its pharmacokinetics and potential side effects, we have developed a radiosynthesis of carbon‐11 (t1/2=20 min) labeled GVG for positron emission tomographic (PET) studies. We report here a novel synthetic strategy to prepare the precursor and to efficiently label GVG with C‐11. 5‐Bromo‐3‐(carbobenzyloxy)amino‐1‐pentene was synthesized in five steps from homoserine lactone, including reduction and methylenation. This was used in a one‐pot, two‐step radiosynthesis. Displacement of bromide with no‐carrier‐added [11C]cyanide followed by acid hydrolysis afforded [1‐11C]GVG with decay corrected radiochemical yields of 27±9% (n=6, not optimized) with respect to [11C]cyanide in a synthesis time of 45 min. Copyright © 2002 John Wiley & Sons, Ltd.