bluuebunny/crossref_metadata_2025_split huggingface dataset:
Enhancement in mineralization of some natural refractory organic compounds by ozonation–aerobic biodegradation
Authors: Saroj Devendra P , Kumar Arun , Bose Purnendu , Tare Vinod 
Published: September 2005

AbstractTwo schemes, the first involving ozonation followed by final aerobic biodegradation (phase I experiments), and the second involving initial aerobic biodegradation, followed by ozonation and subsequent final aerobic biodegradation (phase II experiments), were examined for enhanced mineralization of refractory model compounds, viz. gallic acid, tannin and lignin. In all cases, and irrespective of the applied scheme, chemical oxygen demand (COD), total organic carbon (TOC), COD/TOC ratio, and specific UV absorbance at 280 nm attributed to the model compounds decreased with application of increasing ozone dose. The residual organic matter remaining after ozonation exhibited enhanced aerobic biodegradability in all cases. Further, in all cases and irrespective of the applied scheme, the overall amount of COD and TOC removed through the combination of ozonation and biodegradation processes increased with increase in ozone dose for all three model compounds, and more than 90% COD removal could be achieved with an ozone dose of 3 mg ozone absorbed per mg initial TOC, as compared with approximately 40% COD removal when no ozone was applied. Treatment by the first scheme resulted in the fraction of starting COD removed through biodegradation decreasing with increase in ozone dose in all cases, while this fraction increased or remained constant during treatment using the second scheme. In the case of tannin and lignin, similar overall COD removal could be achieved at lower ozone doses using scheme II. Due to incorporation of the initial aerobic biodegradation step in scheme II, the ozone requirement for additional mineralization, ie mineralization over and above that achieved by aerobic biodegradation, was also lower than that in scheme I. Copyright © 2005 Society of Chemical Industry
Specificities of proteases for use in leather manufacture
Authors: Foroughi Farhad , Keshavarz Tajalli , Evans Christine S 
Published: September 2005

AbstractProteases are used in leather manufacture in the processes of soaking, unhairing and bating of hides and skins. However proteases can be relatively non‐specific in their usage, and for improved efficacy of enzyme biocatalysis within the industry, an analysis of specific activities of enzymes towards skin proteins was undertaken. Most commercial proteases for soaking showed substantial activity against the substrates elastin–Congo Red and Azocoll but little or no activity against keratin–azure and hide powder black. Enzymes used for unhairing in conjunction with 30% of the usual concentration of sulfide to effect chemical unhairing showed moderate activity against all substrates tested (selected as representative of skin proteins), while proteases used in bating showed activity against Azocoll and elastin–Congo Red but had no keratinase activity and little activity against hide powder black. Bating proteases and soaking proteases displayed similar activities at pH 8. Microbes isolated in the screening of organisms from putrefied skins included one fungal and two bacterial isolates whose extracellular enzymes had efficient unhairing activity without the addition of sulfide. Enzyme activities for these proteases included high activity measured against Azocoll with little or no activity against elastin–Congo Red, keratin–azure and hide powder black. Neither elastase nor keratinase activities were determined as being essential for unhairing. Copyright © 2005 Society of Chemical Industry
A simple model for simultaneous methanogenic–denitrification systems
Authors: Garibay‐Orijel Claudio , Ahring Birgitte K , Rinderknecht‐Seijas Noemí , Poggi‐Varaldo Héctor M 
Published: September 2005

AbstractWe describe a useful and simple model for studies of simultaneous methanogenic–denitrification (M–D) systems. One equation predicts an inverse relationship between the percentage of electron donor channeled into dissimilatory denitrification and the loading ratio λ given by grams degradable COD per gram nitrate‐N in the influent. It allows the determination of the extent of use of organic matter by the denitrification and the methanogenic pathways for a given concentration of nitrate salts in the influent. This equation was validated with experimental data from the literature and good agreement between predicted and experimental percentages was found. The other equation allows the calculation of the N nutrient requirements in the ammonia nitrogen form (that is, with oxidation number −3). Copyright © 2005 Society of Chemical Industry
Decolourisation of dyes and dyehouse effluent in a bubble‐column reactor by heterogeneous catalytic ozonation
Authors: Hassan M Mahbubul , Hawkyard Christopher J 
Published: September 2005

AbstractThe decolourisation of aqueous solutions of dyes by ozonation with various heterogeneous catalysts using a bubble‐column reactor was investigated. The catalysts studied were hydrated alumina, activated carbon and ferric oxide supported on silica. The optimum catalyst concentration and pH for decolourisation were determined in each case. Hydrated alumina and silica‐supported ferric oxide showed excellent catalytic activity under acidic conditions, whereas activated carbon was found to be effective under both acidic and alkaline conditions. In addition to studying the effect on individual dyes, tests were carried out on effluent from a commercial dyeing unit. The reaction kinetics in the presence of various catalysts were also monitored. Copyright © 2005 Society of Chemical Industry
Comparison of the surface and catalytic properties of rare earth‐promoted CaO catalysts in the oxidative coupling of methane
Authors: Rane Vilas H , Chaudhari Sopan T , Choudhary Vasant R 
Published: September 2005

AbstractRare earth (viz. La, Ce, Sm, Nd and Yb) promoted CaO catalysts have been investigated, comparing their surface properties (viz. surface area and basicity/base strength distribution) and catalytic activity/selectivity in the oxidative coupling of methane at different reaction conditions (temperatures, 650–800 °C, CH4/O2 ratios, 2.0–8.0 and space velocity, 51 360 cm3 g−1 h−1). The surface properties and catalytic activity/selectivity are strongly influenced by the rare earth promoter and its concentration. Apart from the Sm‐promoted CaO catalyst, both the total and strong basic sites (measured in terms of CO2 chemisorbed at 50° and 500 °C respectively) are decreased due to the promotion of CaO by rare earth metals (viz. La, Ce, Nd and Yb). The catalytic activity/selectivity is strongly influenced by the temperature, particularly below ⩽700 °C, whereas at higher temperature no further effect is seen. The La2O3CaO, Nd2O3CaO and Yb2O3CaO catalysts showed high activity and selectivity, and also their results are comparable. Among the catalysts, Nd‐promoted CaO (with Nd/Ca = 0.05) showed the best performance (19.5% CH4 conversion with 70.8% C2+ selectivity) in the oxidative coupling of methane. A close relationship between the surface density of total and strong basic sites (measured in terms of CO2 chemisorbed at 50° and 500 °C respectively) and the C2+ selectivity and/or C2+ yield has been observed. Copyright © 2005 Society of Chemical Industry
Chiral molecular recognition for the detection and analysis of enantiomers by mass spectrometric methods
Authors: Schug Kevin A. , Lindner Wolfgang 
Published: September 2005

AbstractAs of late, mass spectrometric methods for analysis of enantiomer discriminating systems have received considerable attention. In the last ten years, specific methods focused on measuring enantioselectivities via diastereomeric host–guest associations, collisional dissociation of diastereomeric complexes, and ion‐molecule reactions using chiral selectors have been developed. The ability to evaluate the performance of new chiral selector molecules by MS is particularly intriguing in this context; providing complementary technology to enantioselective gas‐ and liquid‐phase separation strategies already in place. Still, a number of question marks remain to be answered before these methods become commonplace. This review surveys the aspects of the mass spectrometric methods listed above and describes how they can be used to evaluate enantiomer discriminating systems. A short overview comparing the different ionization sources and mass analyzers which are used is also offered. Overall, we seek to address the advantages and limitations of each method, citing specific examples of their use from the literature, for the purpose of understanding what could be done to expand the scope of their implementation. In doing so, we also highlight some of those facets that relate directly to using MS for evaluating molecular recognition, and in particular, chiral molecular recognition systems.
Improved fallow with pigeon pea for soil fertility improvement and to increase maize production in a smallholder crop–livestock farming system in the subhumid zone of Ghana
Authors: Abunyewa A. A. , Karbo K. N. 
Published: September 2005

AbstractPigeon pea is cultivated by most smallholder crop–livestock farmers mainly as a border crop. It is quite often sparsely intercropped in cereal‐based cropping systems in the subhumid zone of Ghana. Management of pigeon pea and its biomass is a promising means of improving many abandoned arable fields but has not been consciously undertaken. The objective of this trial was to explore the use of pigeon pea and the management of its pruned biomass as part of an improved fallow for crop–livestock farming. Three pigeon‐pea management options and a natural fallow (two‐year fallow period) were compared in terms of maize grain yield and changes in soil organic carbon, total nitrogen and cation exchange capacity. Pigeon pea grain yield ranged between 615 and 678 kg ha−1 and 527 and 573 kg ha−1 in the first and second year of fallow, respectively. In the first year after fallow, maize grain yield ranged between 0·43 and 2·39 t ha−1 and was significantly influenced by the fallow system. There was a marked decrease in maize grain on the pigeon pea fallow plots in the second year, ranging between 50 and 38·6 per cent in Kumayili and between 42·6 and 17·6 per cent in Tingoli. After the two‐year fallow period, increase of soil organic carbon on the pigeon pea fallow plot compared with the natural fallow plot was 30·5 per cent, and there was an improvement of total nitrogen (48·5 per cent) and CEC (17·8 per cent). Copyright © 2005 John Wiley & Sons, Ltd.
Activity‐unrelated neural control of myogenic factors in a slow muscle
Authors: Hyatt Jon‐Philippe K. , Roy Roland R. , Baldwin Kenneth M. , Wernig Anton , Edgerton V. Reggie 
Published: September 2005

AbstractThe properties of skeletal muscles are modulated by neural and nonneural factors, and the neural factors can be modulated by activity‐independent as well as activity‐dependent mechanisms. Given that daily activation of fast muscles is considerably less than of slow muscles, we hypothesized that the myogenic properties of the rat soleus (a slow muscle) would be more dependent on activity‐dependent than activity‐independent factors. Muscle mass, MyoD, and myogenin mRNA and protein levels, and satellite cell proliferation and differentiation rates (bromodeoxyuridine incorporation) were examined at 3, 14, and 28 days after either spinal cord isolation (SI, neuromuscular connectivity intact with minimal activation) or denervation (no neural influence). Soleus atrophy was similar in the SI and denervated groups at each time point, although increases in whole‐muscle expression of myogenin and, to a lesser degree, MyoD were lower (P < 0.05) in SI than denervated soleus muscles. Proliferation and differentiation of satellite cells, as well as mitotic activity of connective tissue cells, were lower (P < 0.05) in SI than denervated soleus muscles. In some instances, these changes were not observed until the later time points, i.e., 14 or 28 days. These results demonstrate that the motoneurons that innervate the slow soleus muscle have a significant modulatory influence on some muscle properties via mechanisms that are independent of activation. These activity‐independent modulatory influences, however, are less in the slow soleus than previously observed in fast muscles. Muscle Nerve, 2005
Clinical and subclinical autonomic dysfunction in chronic inflammatory demyelinating polyradiculoneuropathy
Authors: Stamboulis Eleftherios , Katsaros Nikolaos , Koutsis Georgios , Iakovidou Heleni , Giannakopoulou Anastasia , Simintzi Irene 
Published: September 2005

AbstractAutonomic neuropathy, although common in Guillain–Barré syndrome, is considered rare in chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) and has not been systematically investigated in that disorder. The present study was aimed at determining the prevalence of autonomic dysfunction and investigating the integrity of autonomic nervous system (ANS) reflexes in CIDP. We studied 17 patients with idiopathic CIDP and 20 healthy controls. Six quantitative autonomic function tests (AFTs) were used: Valsalva ratio, 30/15 ratio, and inspiration–expiration difference for parasympathetic function; and tilt test, handgrip test, and sympathetic skin response for sympathetic function. Eleven patients had symptoms of autonomic dysfunction. AFTs were abnormal in 13 patients. Parasympathetic and sympathetic systems were affected with equal frequency. The tilt test was abnormal most frequently, followed by the 30/15 ratio. Three patients developed postural hypotension with loss of consciousness during the tilt test. Abnormality of AFTs did not correlate with the presence of dysautonomic symptoms; duration, severity, and clinical course of the disease; or with age or gender of patients. Our study suggests a higher frequency of clinical and subclinical involvement of the ANS in CIDP than previously estimated. Dysautonomic symptoms are frequent but are mild. However, upon prolonged passive standing, autonomic failure can lead to loss of consciousness. The subclinical involvement of the ANS affects mainly the sympathetic vasomotor and parasympathetic cardiovascular fibers. Muscle Nerve, 2005
Atom transfer radical polymerization of methyl methacrylate catalyzed by cobalt catalyst system
Authors: Li Zhong Hui , Zhang Yong Ming , Xue Min Zhao , Zhou Lei , Liu Yan Gang 
Published: September 2005

AbstractA new catalyst system, CoCl2/tris(2‐(dimethyl amino) ethyl)amine (Me6 TREN), was used to catalyze the polymerization of methyl methacrylate (MMA) successfully through atom transfer radical polymerization mechanism. The control over the polymerization was not ideal, the molecular weight distribution of the resulting polymer (PMMA) was relatively broad (Mw/Mn = 1.63–1.80). To improve its controllability, a small amount of hybrid deactivator (FeBr3/Me6TREN or CuBr2/Me6TREN) was added in the cobalt catalyst system. The results showed that the level of control over the polymerization was significantly improved with the hybrid cobalt–iron (or cobalt–copper) catalyst system; the polydispersity index of the resulting polymer was reduced to a low level (Mw/Mn = 1.15–1.46). Furthermore, with the hybrid cobalt–iron catalyst, the dependence of the propagation rate on the temperature and the copolymerization of methacrylate (MA) with PMMA‐Br as macroinitiator were also investigated. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 5207–5216, 2005
Some novel accelerating agents for nitroxide‐mediated living free‐radical polymerization
Authors: Jianying Huang , Jian Lin , Minghua Lin , Qiang Lin , Lizong Dai , Yousi Zou 
Published: September 2005

AbstractMalononitrile (MN), trifluoroacetic acid anhydride, acetylacetone, acetoacetic ester, and diethyl malonate have been identified as novel rate‐accelerating additives for nitroxide‐mediated living free‐radical polymerization. Among these additives, MN has the greatest accelerating effect. Adding MN at an MN/2,2,6,6‐tetramethylpiperidine‐oxyl (TEMPO) molar ratio of 4.0 results in a nearly 20 times higher rate of polymerization of styrene (St), and adding MN at an MN/TEMPO molar ratio of 2.5 results in a nearly 15 times higher rate of copolymerization of St and methyl methacrylate. The polymerization of St proceeds in a living fashion, as indicated by the increase in the molecular weight with time and conversion and the relatively low polydispersity. The polymerization rate of St is so quick that the conversion reaches 70% within 1 h at 125 °C when the molar ratio of MN to TEMPO is 4:1. Moreover, the reaction temperature can be reduced to 110 °C. A possible explanation for this effect is that the formation of hydrogen bonds between the MN and TEMPO moiety weakens the CON bond at the end of the polymer chain. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 5246–5256, 2005
Oligoethylene‐end‐capped polylactides
Authors: Abayasinghe Nilmini K. , Glaser Sibylle , Prasanna K. , Perera U. , Smith Dennis W. 
Published: September 2005

AbstractOligoethylene‐end‐capped polylactides were synthesized through the ring‐opening polymerization of L‐lactide with alcohol‐terminated oligoethylenes as macroinitiators. The polymerization of L‐lactide was carried out in bulk at 130 °C in the presence of stannous octoate and primary alcohols with four different molecular weights: 350, 425, 550, and 700 g/mol. The end‐capped copolymers that formed had a number‐average molecular weight of approximately 40,000 (weight‐average molecular weight/number‐average molecular weight = 1.7) according to gel permeation chromatography and were highly crystalline in comparison with the similarly formed homopolymer of L‐lactide. The copolymer structure was characterized by Fourier transform infrared, NMR, matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry, and differential scanning calorimetry analysis. This work focused on developing more crystallizable and hydrolytically stable polylactide derivatives that could potentially be used as compatibilizers in polylactide–polyolefin blends or as nucleating agents for poly(L‐lactide) or other polyesters. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 5257–5266, 2005
Synthesis of electroluminescent copoly(aryl ether)s containing alternate 1,4‐distyrylbenzene derivatives and aromatic 1,3,4‐oxadiazole or 3,3″‐terphenyldicarbonitrile segments
Authors: Hsieh Bar‐Yuan , Yeh Kun‐Ming , Chen Yun 
Published: September 2005

AbstractNew copoly(aryl ether)s (P1–P3) containing alternate 2,5‐dihexyloxy‐1,4‐di(m‐ethoxystyryl)benzene (P1, P2) or 2,5‐dihexyloxy‐1,4‐distyrylbenzene (P3) chromophores and aromatic 1,3,4‐oxadiazole (P1) or 3,3″‐terphenyldicarbonitrile (P2, P3) segments were prepared by Horner reaction (P1 and P2) or nucleophilic displacement reaction (P3). They are basically amorphous materials with 5% weight‐loss temperature above 410 °C. Their absorption, photoluminescence spectra, and quantum yields are dependent on the composition of the isolated fluorophores. The emissions are exclusively dominated by 1,4‐distyrylbenzene segments via excitation energy transfer from electron‐transporting 1,3,4‐oxadiazole (P1) or 3,3″‐terphenyldicarbonitrile (P2, P3) chromophores. The HOMO and LUMO energy levels have been estimated from their cyclic voltammograms, and the observations confirm that oxidation and reduction start from the emitting 1,4‐distyrylbenzene and electron‐transporting segments, respectively, indicating that both carriers affinity can be enhanced simultaneously. Among the two‐layer PLED devices (ITO/PEDOT/P1–P3/Al), P1 exhibits the best performance with a turn‐on field of 4 × 105 V/cm and a maximum luminance of 225 cd/m2. However, P2 emits green–yellow light (555 nm), owing to the excimer emission. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 5009–5022, 2005
Polyisophthalamides with heteroaromatic pendent rings: Synthesis, physical properties, and water uptake
Authors: Ferreiro Juan J. , de la Campa Jose G. , Lozano Angel E. , de Abajo Javier 
Published: September 2005

AbstractA set of novel aromatic polyamides containing pyridine pendent groups was prepared from aromatic diamines and new monomers that are 5‐substituted derivatives of isophthalic acid bearing nicotinamide, isonicotinamide, or picolinamide groups. The polymers were obtained in high yield and high molecular weight by the phosphorylation method of polycondensation. They were characterized by spectroscopic and chromatographic methods and several of their properties were investigated. All of the polymers were soluble in polar aprotic solvents and gave films of good mechanical properties. Glass transition temperatures were higher than that of the reference polymer, poly(m‐phenyleneisophthalamide) (IP‐MPD), while the thermal resistance, defined by the initial decomposition temperature observed by thermogravimetry, was in the range 370–420 °C, lower by 30–70 °C than that of IP‐MPD. The presence of a pendent pyridine group and an additional amide side group per repeat unit made the polymers essentially amorphous and greatly improved their abilities to absorb water in comparison with nonsubstituted polyamides. Water uptake values up to 15% were observed at 65% relative humidity. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 5300–5311, 2005
Curcumin: A naturally occurring long‐wavelength photosensitizer for diaryliodonium salts
Authors: Crivello James V. , Bulut Umut 
Published: September 2005

AbstractCurcumin, a naturally occurring, intensely yellow dye extracted from the spice turmeric, is an efficient photosensitizer for diaryliodonium salt photoinitiators at wavelengths ranging from 340 to 535 nm. With curcumin as a photosensitizer, it is possible to carry out the cationic photopolymerization of a wide variety of epoxide, oxetane, and vinyl monomers with long‐wavelength UV and visible light. An example of the photopolymerization of an epoxide monomer with ambient solar irradiation is provided. Several other curcumin analogues were synthesized, and their use as photosensitizers is examined. With such photosensitizers, the range of spectral sensitivity can be extended well into the visible region of the electromagnetic spectrum. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 5217–5231, 2005
High performance benzoxazine monomers and polymers containing furan groups
Authors: Liu Ying‐Ling , Chou Ching‐I 
Published: September 2005

AbstractFuran‐containing benzoxazine monomers, 3‐furfuryl‐3,4‐dihydro‐2H‐1,3‐benzoxazine (P‐FBz) and bis(3‐furfuryl‐3,4‐dihydro‐2H‐1,3‐benzoxazinyl)isopropane (BPA‐FBz), were prepared using furfurylamine as a raw material. The chemical structures of P‐FBz and BPA‐FBz were characterized with FTIR, 1H NMR, elemental analysis, and mass spectrometry. Formation of furfurylamine Mannich bridge networks in the polymerizations of P‐FBz and BPA‐FBz increased the cross‐linking densities and thermal stability of the resulting polybenzoxazines. P‐FBz‐ and BPA‐FBz‐based polymers also exhibited high glass transition temperatures above 300 °C, high char yields, and low flammability with limited oxygen index values of 31. The dielectric (Dk = 3.21–3.39) and mechanical properties (high storage modulus of 3.0–3.9 GPa and low coefficient of thermal expansion of 37.7–45.4 ppm) of the P‐FBz‐ and BPA‐FBz‐based polymers were superior or comparable to other polybenzoxazines. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 5267–5282, 2005