Abstract High thermal gradient formed during the fusion welding process results in development of undesirable residual stress in the weldments. This stress is developed due to restraint by the parent metal during weld solidification. The high heat input results in non-uniform heat distribution across the weld region in other words non-uniform microstructural development across the weld region and hence the mechanical properties of the joint are often not uniform. In order to avoid inhomogeneity in the mechanical properties and also to reduce/eliminate undesirable residual stress, the welded samples are given post welding heat treatment. In this research, 500 µm thin SS-316L sheets are welded using micro plasma arc welding process and then the welded specimens are heat treated. The welding experiments are conducted by varying welding speed, welding current and stand-off distance. Weld bead microstructure, micro-hardness, ultimate tensile strength (UTS), yield strength and percentage elongation are determined before and after heat treatment. The effects of welding heat input and process parameters on the measured weld qualities are studied. Analysis of variance is also performed to estimate the influence of factors and their interaction on the weld quality. The post weld heat treatment results in an increase in the grain size of the HAZ and is found in the range of 38.96 µm to 56.22 µm whereas for as-welded samples it is in the range of 29.88 µm to 50.40 µm. The average UTS value of the heat treated samples is increased by 9.9% compared to the as-welded samples. The hardness of the fusion zone varies in the range of 175-215 HV.

Abstract Piper betle L., is an evergreen perennial creeper belonging to family Piperaceae and is known to possess numerous medicinal properties. Current study focuses on evaluating antioxidant and antimicrobial potential of betel leaf. For the present study, distilled water, hexane, acetone and ethanolic extracts of two varieties of betel leaves: Meetha paan and Banarasi paan were used. Biochemical tests such as proximate analysis (moisture, ash, protein, lipids, minerals viz., sodium and potassium), antioxidant activity tests (DPPH radical scavenging activity, total phenolics, ascorbic acid, reducing power) and antimicrobial test (antibacterial and antifungal susceptibility test) against four pathogens viz., B. subtilis, E. coli, A. niger and S. cerevisiae were determined. Ethanolic extract had the highest antioxidant activity (89.46% inhibition), while the aqueous extract exhibited lowest antioxidant activity (62.03% inhibition). With increasing concentration (5, 10, 25 and 50 µg/mL), the reducing power of leaf extracts also increased. The ascorbic acid was not significant in Banarasi paan (5.21mg/100 g) and Meetha paan (5.20mg/100 g). The highest antibacterial activity of ethanolic extract (Banarasi paan) may be attributed to the presence of phytosterols in the leaf varieties. Antioxidant and antimicrobial potential study will help to build a database and promote the utilization of betel leaf as a medicinal herb.

The synthesis of novel amino alcohol derivatives based on cardanol and glycerol were achieved in good yields and characterized by 1H and 13C NMR (nuclear magnetic resonance) and MS (mass spectrometry). In addition, we evaluated the in vitro antimicrobial activity against Gram-positive (Staphylococcus aureus, standard and clinical strains), Gram-negative (Escherichia coli) and M. tuberculosis bacterial strains. The bioassay results indicated that four compounds showed activity against S. aureus, including the clinical resistant strain, with MIC (minimum inhibitory concentration) ranging from 3.90 to 15.60 µg mL-1 and M. tuberculosis, with MIC90 (minimum inhibitory concentration required to inhibit the growth of 90% of organisms) ranging from 3.18 to 7.36 µg mL-1.

PURPOSE: To present our experience and discuss the various endourological approaches for treating forgotten encrusted ureteral stents associated with stone formation. MATERIALS AND METHODS: From July 2006 to December 2008, 14 patients (11 men and 3 women) with encrusted ureteral stents were analyzed. The average indwelling time of the stent was 4.9 years (range 1 to 12). Plain-film radiography was used to evaluate encrustation, stone burden, and fragmentation of the stents. Intravenous urogram and a Tc99m diethylene triamine penta acetic-acid renogram was used to assess renal function. RESULTS: In seven patients, the entire stent was encrusted, in three patients the encrustation was confined to the ureteral and lower coil part of the stent, two patients had encrustation of the lower coil, and minimal encrustation was observed in two patients. Percutaneous nephrolithotomy was performed in 5 cases and retrograde ureteroscopy with intra-corporeal lithotripsy in 9 patients. Cystolithotripsy was used to manage the distal coil of the encrusted stent in eight patients. Simple cystoscopic removal of the stents with minimal encrustation was carried-out in two cases. Looposcopy and removal of the stent was performed in one patient with an ileal conduit and retained stent. Only one patient required open surgical removal of the stent. Thirteen out of 14 patients were rendered stone and stent free in one session. All except two stents were removed intact and stone analysis of encrustation and calcification revealed calcium oxalate and calcium phosphate in the majority of the cases. CONCLUSION: Endourological management of forgotten encrusted stents is highly successful and often avoids the need for open surgical techniques.

Polycrystalline samples of ZrO2 added (Na1/2Bi1/2)TiO3 were prepared using high-temperature solid-state reaction method at 1050ºC and subsequent sintering at 1090ºC in air atmosphere. Rietveld analyses of XRD data indicated the formation of a single-phase hexagonal structure with R3c symmetry. Dielectric studies revealed the relaxor behaviour. The addition of ZrO2 to (Na1/2Bi1/2)TiO3 shifted phase transition temperature as well as depolarization temperature to higher side which is desirable for piezoelectric applications. The frequency dependence of the temperature of the permittivity maximum was modeled using Vogel-Fulcher relation. The dielectric relaxation in the system is found to be analogous to the magnetic relaxation in spin-glass system.

A finalidade principal deste trabalho foi estudar o tratamento anaeróbio de resíduos sólidos orgânicos com alta e baixa concentração de sólidos. O sistema experimental se compunha de dois reatores com capacidade unitária de 2.200 L, enquanto o substrato utilizado era composto de resíduos sólidos vegetais e lodo de esgotos sanitários, sendo um dos reatores alimentado com substrato contendo 20% de sólidos totais (80% de umidade) e o outro com apenas 5% de sólidos totais (95% de umidade). Verificou-se, quando da utilização de substrato contendo 5% (percentagem em peso) de sólidos totais, que o tempo de retenção de sólidos requerido para que fossem alcançados 80% de redução da massa de DQO aplicada, foi de 90 dias, propiciando uma taxa de produção de gás metano de 0,25 Nm³ CH4 kg-1 DQO Aplicada. Com relação ao substrato contendo 20% de sólidos totais, o tempo de retenção de sólidos requerido para bioestabilizar 80% da massa de DQO aplicada, foi de 270 dias, com taxa de produção de gás metano de 0,10 Nm³ CH4 kg-1 DQO Aplicada.

In this study the anaerobic treatment of organic solid waste with high and low concentrations of solids was studied. The experimental system comprised of two reactors, with unitary capacity of 2,200 L, while the used substrate was composed of solid vegetable waste and sludge. One of the reactors was loaded with substrate containing 20% of total solids and the other with only 5% of total solids on weight basis. It was verified that, for the substrate containing 5% of total solids, the retention time of solids required for 80% reduction of the applied COD mass was 90 days, during which the methane gas production rate was of 0.25 Nm³ kg-1 COD Applied; whereas in the substrate containing 20% of total solids, the retention time of solids required for biostabilization of 80% of the mass of applied COD was 270 days, with a methane gas production rate of 0.1 Nm³ CH4 kg-1 COD Applied.

A estequiometria de poliânions formados pela ação do ácido nítrico sobre a solução de tungstato de sódio (< 0,01M) foi estudada por meio de técnicas eletrométricas envolvendo titulações potenciométricas e condutométricas. As inflexões e degraus bem definidas nas curvas de titulações forneceram evidências convincentes pela existência de poliânions, para-W12O41(10-) e meta-W12O39(6-) nas faixas do pH 5,7-6,0 e 3,6-4,1; correspondendo a razão H+:WO4(2-) como 7:6 e 9:6, respectivamente. A interação entre soluções de nitrato de lantânio e tungstato de sódio a específicos níveis de pH 8,0; 5,9 e 4,0 também foi estudada por titulações potenciométricas e condutométricas, nos meios aquoso e etanólico, com cada reagente usado alternadamente como titulante. Os experimentos eletrométricos forneceram evidências incontestáveis sobre a formação de tungstatos normal-La2O3.3WO3, para-5La2O3.36WO3 e meta-La2O3.12WO3 nas proximidades de valores de pH 6,3; 5,0 e 4,2; respectivamente. Investigações analíticas sobre os precipitados formados confirmam os resultados do estudo eletrométrico.

The stoichiometry of the polyanions formed by the action of nitric acid on sodium tungstate (< 0.01M) has been studied by means of electrometric techniques involving pH-potentiometric and conductometric titrations. The well defined inflections and breaks in the titration curves provide evidence for the existence of the polyanions, para-W12O41(10-) and meta-W12O39(6-) corresponding to the ratio of H+:WO4(2-) as 7:6 and 9:6 in the pH ranges 5.7-6.0 and 3.6-4.1, respectively. The interaction of lanthanum nitrate with sodium tungstate solutions, at specific pH levels 8.0, 5.9 and 4.0 was also studied by pH and conductometric titrations, in aqueous and alcoholic media, with each of the reagents alternatively used as titrant. The electrometric experiments provide definite evidence of the formation of normal-La2O3.3WO3, para-5La2O3.36WO3 and meta-La2O3.12WO3 tungstates in the vicinity of pH 6.3, 5.0 and 4.2, respectively. Analytical investigations on the precipitates formed confirm the results of the electrometric study.

Doze novos complexos hexacoordenados de rutênio(II) com amidas, [RuH(CO)(PPh3)2(L2 )], foram sintetizados a partir do precursor [RuH2(CO)(PPh3)3]. Esses complexos foram caracterizados por análise elementar e por espectroscopias no UV-vis, no infravermelho e RMN de ¹H, 13C e 31P. Fórmulas moleculares e estruturas octaédricas foram propostas para os produtos. Os complexos mostraram-se eficientes na redução catalítica do grupo nitro em drogas do tipo cloranfenicol e metronidazol. Os rendimentos dos produtos de redução foram determinados espectrofotometricamente.

Twelve new hexacoordinated ruthenium(II) complexes with organic amides, [RuH(CO)(PPh3)2(L2 )], have been synthesized by treating the precursor, [RuH2(CO)(PPh3)3], with twelve different amide proligands separately. These complexes were characterized by elemental analysis and by UV-vis, IR, ¹H, 13C and 31P NMR spectroscopies. Molecular formulae and octahedral structures have been tentatively proposed for the products. These complexes were found to be efficient in the catalytic reduction of NO2-containing drugs such as chloramphenicol and metronidazole to their amino derivatives. The percent yields of the reduction products were determined spectrophotometrically.

This work on the process of biosorption of nickel and chromium in an ascendant continuous-flow, fixed packed-bed bioreactor of sanitary sewage sludge was conducted in a search for solutions to the environmental problem caused by heavy metals. Analysis of the results demonstrated that the absorbent had an extraordinary capacity for biosorption of the heavy metals studied at about 9.0 pH of the effluent, with a removal percentage of over 90.0% for the two metals. Chemometric study results demonstrated that 20 days of the experimental system function were sufficient for achieving the maximum efficiency of sorption of the heavy metals studied by the sanitary sewage sludge employed.

A natureza precisa da reação entre soluções de ácido nítrico e de ortho-vanadato de sódio foi estudada por técnicas electrométricas envolvendo titulações potenciométricas e condutométricas. As inflexões e degraus bem definidas nas curvas de titulações confirmaram a existencia de anions, piro-V2O7(4-), meta-VO3- e poli-H2V10O28(4-) correspondendo as razões de VO4(3-):H+ como 1:1, 1:2 e 1:2,6 na vizinhança do pH 10,5; 7,4 e 3,6, respectivamente. Ainteração entre soluções de nitrato de cério(III) e vanadato de sódio a específicos níveis de pH 12,4; 10,5; 7,4 e 3,6 também foi estudada por titulações potenciométricas e condutométricas entre os reagentes. Os pontos finais obtidos a partir de inflexções nítidas nas curvas de titulações forceram evidências incontestáveis sobre a formação e precipitação de vanadatos orto-Ce2O3.V2O5, piro-2Ce2O3.3V2 O5 e meta-Ce2O3.3V2O5 de cério nas proximidades dos valores de pH 7,4; 6,2 e 4,8, respectivamente. Investigações analíticas sobre os precipitados formados confirmam os resultados do estudo eletrométrico.

The precise nature of the reaction between nitric acid and sodium ortho-vanadate solutions has been studied by means of electrometric techniques involving potentiometric and conductometric titrations. The well defined inflections and breaks in the titration curves confirm the existence of the anions, pyro-V2O7(4-), meta-VO3- and poly-H2V10O28(4-) corresponding to the ratios of VO4(3-):H+ as 1:1, 1:2 and 1:2.6 in the neighborhood of pH 10.5, 7.4 and 3.6, respectively. The interaction of cerium(III) nitrate with sodium vanadate solutions, at specific pH levels 12.4, 10.5, 7.4 and 3.6 was also studied by potentiometric and conductometric titrations between the reactants. The end-points obtained from the sharp inflections in the titration curves provide definite evidence for the formation and precipitation of cerium ortho-Ce2O3.V2O5, pyro-2Ce2O3.3V2O5 and meta-Ce2O3.3V2O5 vanadates in the neighborhood of pH 7.4, 6.2 and 4.8, respectively. Analytical investigations on the precipitates formed confirm the results of the electrometric study.

Relatamos caso de homem de 66 anos de idade portador de insuficiência cardíaca classe funcional (NYHA) IV que foi submetido a terapia de ressincronização cardíaca por implante de marcapasso biventricular. O paciente foi avaliado antes e 48 horas após o implante do marcapasso com o emprego da ecocardiografia tridimensional transtorácica em tempo real. A utilização da ecocardiografia tridimensional contribuiu para o entendimento do mecanismo envolvido na ressincronização cardíaca através da demonstração da melhor sincronização dos segmentos cardíacos, o que resultou em melhora clínica do paciente.

We report the case of a 66-year-old man with heart failure NYHA class IV treated with biventricular pacing for cardiac resynchronization. The patient was evaluated by real-time three-dimensional transthoracic echocardiography before and 48 hours after pacemaker implantation. The use of three-dimensional echocardiography contributed to understanding the underlying mechanism involved in cardiac resynchronization therapy by demonstrating enhanced synchrony of myocardial segments, which resulted in the patient's clinical improvement.

Resumo Lagoas de estabilização constituem tecnologia já bastante consolidada para o tratamento de águas residuárias, sendo considerada pela Organização Mundial da Saúde como uma das formas de tratamento de esgotos sanitários mais apropriadas, quando levado em consideração o reúso de efluentes para a agricultura e, em especial quando se trata de países em desenvolvimento. Este trabalho foi realizado em uma série de lagoas de estabilização em escala piloto, sendo uma facultativa e três de maturação, com profundidade variando de 0,44 a 0,57 m. O substrato era constituído por uma mistura de esgoto doméstico e percolado, previamente tratado em reator UASB. O sistema experimental foi monitorado em duas diferentes etapas, uma com tempo de detenção hidráulica de 15 e 10 dias nas etapas I e II. A eficiência de remoção de coliformes termotolerantes foi de 99,98% em ambas as etapas do trabalho enquanto que a de material carbonáceo, expresso em termos de DBO5, foi de 87,0 e 67,7% nas etapas I e II, respectivamente.

Abstract Waste stabilization ponds are a well established wastewater treatment technology, being considered by World Health Organization as one of the most appropriate technology for domestic wastewater when agricultural reuse is considered, and in special for developing countries. This study was performed in a series of pilot-scale waste stabilization ponds, being one facultative a three maturation ponds, with depths varying from 0,44 to 0,57 m. Substrate consisted of misture domestic wastewater and leachate previously treated in UASB reator. The experimental system was monitored in two different phases, in which the hydraulic retention times were 15 (phase I) and 10 days (phase II). Termotolerant coliform removal efficiency was 99,98% in both phases, while organic matter (BOD5) removal were 87,0 and 67,7% for phase I and II, respectively.

A natureza precisa da reação entre ácido clorídrico e orto-vanadato de sódio foi estudada por técnicas eletrométricas envolvendo titulações potenciométricas e condutométricas. As inflexões e degraus bem definidas nas curvas de titulações confirmaram a existência de ânions, pyro-V2O7(4-) , meta-VO3- e poly-H2V10O28(4-) correspondendo às razões de VO4(3-):H+ como 1:1, 1:2 e 1:2,6 na vizinhança do pH 10,5; 7,4 e 3,6, respectivamente. A interação entre soluções de cloreto de níquel e vanadato de sódio a específicos níveis de pH 12,4; 10.5; 7,4 e 3,6 também foi estudada por titulações potenciométricas e condutométricas entre os reagentes. Os pontos finais obtidos a partir de inflexões nítidas nas curvas de titulações forneceram evidências incontestáveis sobre a formação de vanadatos ortho-3NiO.V2O5, pyro-2NiO.V2O5 e meta-NiO.V2O5 de níquel nas proximidades dos valores de pH 8,9; 8,0 e 6,8; respectivamente. Investigações analíticas sobre os precipitados formados confirmam os resultados do estudo eletrométrico.

The precise nature of the reaction between hydrochloric acid and sodium ortho-vanadate solution has been studied by means of electrometric techniques involving potentiometric and conductometric titrations. The well defined inflections and breaks in the titration curves confirm the existence of the anions, pyro-V2O7(4-) , meta-VO3- and poly-H2V10O28(4-) corresponding to the ratios of VO4(3-):H+ as 1:1, 1:2 and 1:2.6 in the neighborhood of pH 10.5, 7.4 and 3.6, respectively. The interaction of nickel chloride with sodium vanadate solutions, at specific pH levels 12.4, 10.5, 7.4 and 3.6 was also studied by potentiometric and conductometric titrations between the reactants. The end-points obtained from the sharp inflections in the titration curves provide definite evidence for the formation of ortho-3NiO.V2O5, pyro-2NiO.V2O5 and meta-NiO.V2O5 vanadates of nickel in the vicinity of pH 8.9, 8.0 and 6.8, respectively. Analytical investigations on the precipitates formed confirm the results of the electrometric study.

Recently, thermoanalytic methods have frequently been used in the characterization of oils and fats. In this work, thermoanalytic and kinetic parameters of sunflower oils, with and without antioxidants, were evaluated using thermogravimetry / derivative thermogravimetry and differential scanning calorimetry. The thermogravimetric profiles for the sunflower oils had similar characteristics, showing a level stretch indicative of stability up to about 200ºC. Thermal decomposition of these oils occurred in three stages, related to the decomposition of polyunsaturated, monounsaturated and saturated fatty acids, respectively. DSC curves show two events that characterize the polymerization and decomposition of triglycerides. The heat capacities of the sunflower oils, obtained by DSC, showed a good correlation and were dependent on the composition of fatty acids. The kinetic parameters, obtained by non isothermal thermogravimetry by the Coats and Redfern, Madhusudanan, Horowitz and Metzger and Van Krevelen methods, were dependent on the antioxidant used. Increasing the frying time produced a decrease in the onset of thermal decomposition temperature in the sunflower oils analyzed.

Em feiras livres e centrais de abastecimento são produzidas quantidades bastante significativas de resíduos sólidos, com características favoráveis ao aproveitamento integral em processo de bioestabilização anaeróbia. O processo de bioestabilização é realizado em reatores anaeróbios de batelada (RAB), com tempo de detenção de sólidos variando de 250 a 300 dias originando, como produtos finais, o biogás, com cerca de 60% de gás metano, além de composto orgânico parcialmente bioestabilizado. Neste trabalho, foram utilizados resíduos sólidos orgânicos tipicamente vegetais, advindos de centrais de abastecimento, feiras livres e lodo de esgoto sanitário. O sistema experimental utilizado era constituído basicamente por um reator anaeróbio de batelada, com capacidade unitária de 2200 litros, além de outros dispositivos complementares. O sistema experimental foi instalado e monitorado na Estação Experimental de Tratamento Biológico de Esgoto Sanitário, situada no Bairro do Tambor, na cidade de Campina Grande, Estado da Paraíba, no período de janeiro a setembro de 2001. No processo de monitoração foram realizadas caracterizações sistemáticas das frações sólidas, líquidas e gasosas. Após análise dos dados, ficou evidenciada a viabilidade desta alternativa de tratamento, restando ser investigada ainda a viabilidade econômica, quando comparada com outras alternativas tecnológicas de tratamento de resíduos sólidos orgânicos.

Significant quantity of organic solid waste with favorable characteristics for integral utilization in anaerobic biostabilization is produced in free markets and supply centers. The process is conducted in anaerobic batch reactors (ABR), with detention time of solids varying from 250 to 300 days, producing biogas with about 60% of methane, besides the partially biostabilized organic compost as the final product. In this study, the organic solid waste used was typically of vegetables, originated from the supply centers, free markets and sanitary wastewater sludge. The experimental system used was basically constituted of a batch anaerobic reactor of 2200 L capacity, besides the other complementary devices. The experimental system was installed and monitored during the period of January to September 2001 at the Experimental Station for Biological Treatment of Sanitary Sewage, located at Tambor, Campina Grande, in the State of Paraíba, Brazil. During the process of monitoring the systematic characterization of the solid, liquid and gaseous fractions were realized. After analyzing the data, the feasibility of this alternative treatment, was evidenced although the economic viability in comparison to other technological alternatives of treatment of organic solid waste remains to be tested.