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1.
Environ Sci Pollut Res Int ; 26(26): 26869-26882, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31302892

RESUMO

The degradation of organic contaminants in actual textile wastewater was carried out by iron carbon (Fe-C) micro-electrolysis. Different Fe-C micro-electrolysis systems (SIPA and SISA) were established by using scrap iron particle (SIP) and scrap iron shaving (SIS) as anode materials. The optimal condition of both systems was obtained at the initial pH of 3.0, dosage of 30 g/L and Fe/C mass ratio of 1:1. Commercial spherical Fe-C micro-electrolysis material (SFC) was used for comparison under the same condition. The results indicated that total organic carbon (TOC) and chroma removal efficiencies of SIPA and SISA were superior to that of SFC. Total iron concentration in solution and XRD analysis of electrode materials revealed that the former showed relatively high iron corrosion intensity and the physicochemical properties of scrap iron indeed affected the treatment capability. The UV-vis and 3DEEM analysis suggested that the pollutants degradation was mainly attributed to the combination of reduction and oxidation. Furthermore, the potential degradation pathways of actual textile wastewater were illustrated through the GC-MS analysis. Massive dyes, aliphatic acids, and textile auxiliaries were effectively degraded, and the SIPA and SISA exhibited higher performance on the degradation of benzene ring and dechlorination than that by SFC. In addition, SIPA and SISA exhibited high stability and excellent reusability at low cost. Graphical abstract.


Assuntos
Eletrodos , Eletrólise/métodos , Ferro/química , Indústria Têxtil , Eliminação de Resíduos Líquidos/métodos , Carbono/química , Corantes/química , Custos e Análise de Custo , Eletrólise/economia , Eletrólise/instrumentação , Concentração de Íons de Hidrogênio , Oxirredução , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta , Eliminação de Resíduos Líquidos/economia , Eliminação de Resíduos Líquidos/instrumentação , Águas Residuárias/química , Poluentes Químicos da Água/química , Difração de Raios X
2.
Environ Sci Pollut Res Int ; 26(11): 10673-10684, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30778943

RESUMO

In the transportation of petroleum, large amount of oil polluted water will be produced, and the oil polluted water pumping into ocean will destroy ocean environment. To address oil-bearing ballast water, we fabricated a novel type of Fe-C microelectrolysis filler by using magnet powder, coconut shell biochar powder, bentonite, ammonium oxalate, and nickel powder. The COD and oil content removal efficiencies of 100 g/L oily wastewater were approximately 79.82% and 91.68%, respectively, after 100 min treatment at the following conditions: Fe-C mass ratio, 5:1; bentonite content, 20%; calcination temperature, 900 °C; calcination time, 2 h; ammonium oxalate content, 1.5%; and amount of nickel addition, 6.78%. The characteristics of the Fe-C microelectrolysis filler were analyzed. The surface structure of the filler was loose and porous, and its pores were developed. The Brunauer-Emmett-Teller (BET) surface area reached 49.4667 m2 g-1. A microelectrolysis filler is mainly mesoporous and contains large pores. Its average pore size is 2.6942 nm. Meanwhile, the results of our XRD analysis showed that some fillers were metal oxides, and most of them were simple metal substances.


Assuntos
Eletrólise/métodos , Águas Residuárias/química , Poluentes Químicos da Água/química , Bentonita/química , Eletrólise/instrumentação , Níquel/química , Petróleo/análise , Temperatura , Purificação da Água/métodos
3.
J Orthop Surg Res ; 14(1): 31, 2019 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-30683124

RESUMO

BACKGROUND: Both manual therapy techniques and dry needling have shown to be effective treatment options for the treatment of plantar heel pain; however, in recent years, other techniques based on dry needling (DN), such as percutaneous needle electrolysis (PNE), have also emerged. Currently, PNE is being used in clinical practice to manage myofascial trigger points, despite the lack of studies comparing the effects of this technique over dry needling. Therefore, the aim of this randomized controlled study is to compare the effectiveness of DN versus PNE for improving the level of pain experienced by patients suffering from plantar heel pain provoked by myofascial trigger points. METHODS: A randomized controlled trial will be conducted with blinded participants and outcome assessors. A sample of 94 patients with a medical diagnosis of plantar heel pain will be recruited and divided into two treatment groups. Eligible participants will be randomly allocated to either (a) treatment group with DN and a self-stretching home program or (b) treatment group with PNE and a self-stretching home program. Each group will receive one treatment session per week over a period of 4 weeks. The primary outcome measure will be the pain subscale of the Foot Health Status Questionnaire. The secondary outcome measures will be a visual analogue scale for pain (average and highest level of pain experienced during the previous 48 h; level of pain immediately after the treatment session) and health-related quality of life (assessed using the EuroQoL-5 dimensions). Cost-effectiveness data will be extracted based on the EuroQoL-5 dimensions. Follow-up measurements will take place at baseline and at 4, 8, 12, 26, and 52 weeks. DISCUSSION: The justification for this trial is the need to improve current understanding regarding the effectiveness of treatments targeting the rehabilitation of plantar heel pain. This study will be the first randomized controlled trial to directly compare the effectiveness of DN and PNE combined with a specific stretching program for the treatment of plantar heel pain provoked by myofascial trigger points. TRIAL REGISTRATION: Clinical Trials NCT03236779. Registered at clinicaltrials.gov 2 August 2017.


Assuntos
Terapia por Acupuntura/métodos , Eletrólise/métodos , Fasciíte Plantar/terapia , Agulhas , Manejo da Dor/métodos , Medição da Dor/métodos , Terapia por Acupuntura/instrumentação , Adulto , Método Duplo-Cego , Eletrólise/instrumentação , Fasciíte Plantar/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Manejo da Dor/instrumentação , Estudos Prospectivos , Resultado do Tratamento , Adulto Jovem
4.
ChemSusChem ; 10(1): 258-265, 2017 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-27739632

RESUMO

A simple chemical bath deposition is used to coat a complex porous ceramic scaffold with a conformal Ni layer. The resulting composite is used as a solid oxide fuel cell electrode, and its electrochemical response is measured in humidified hydrogen. X-ray tomography is used to determine the microstructural characteristics of the uncoated and Ni-coated porous structure, which include the surface area to total volume, the radial pore size, and the size of the necks between the pores.


Assuntos
Fontes de Energia Elétrica , Eletrólise/métodos , Níquel/química , Eletroquímica , Eletrodos , Eletrólise/instrumentação , Porosidade
5.
Environ Sci Pollut Res Int ; 22(20): 15812-20, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26036588

RESUMO

Combination of ozone together with electrolysis (ozone-electrolysis) is a promising wastewater treatment technology. This work investigated the potential use of carbon nanotube (CNT)-based gas diffusion cathode (GDC) for ozone-electrolysis process employing hydroxyl radicals (·OH) production as an indicator. Compared with conventional active carbon (AC)-polytetrafluoroethylene (PTFE) and carbon black (CB)-PTFE cathodes, the production of ·OH in the coupled process was improved using CNTs-PTFE GDC. Appropriate addition of acetylene black (AB) and pore-forming agent Na2SO4 could enhance the efficiency of CNTs-PTFE GDC. The optimum GDC composition was obtained by response surface methodology (RSM) analysis and was determined as CNTs 31.2 wt%, PTFE 60.6 wt%, AB 3.5 wt%, and Na2SO4 4.7 wt%. Moreover, the optimized CNT-based GDC exhibited much more effective than traditional Ti and graphite cathodes in Acid Orange 7 (AO7) mineralization and possessed the desirable stability without performance decay after ten times reaction. The comparison tests revealed that peroxone reaction was the main pathway of ·OH production in the present system, and cathodic reduction of ozone could significantly promote ·OH generation. These results suggested that application of CNT-based GDC offers considerable advantages in ozone-electrolysis of organic wastewater.


Assuntos
Eletrólise/métodos , Radical Hidroxila/química , Nanotubos de Carbono/química , Ozônio/química , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/química , Difusão , Eletrodos , Eletrólise/instrumentação , Eliminação de Resíduos Líquidos/instrumentação , Águas Residuárias/química
6.
Artigo em Inglês | MEDLINE | ID: mdl-25837564

RESUMO

The objective of this study was to determine the effectiveness of two-stage electro-coagulation (EC) process using multi-parameter optimization for treating bio-digested distillery spent wash by stainless steel (SS) and aluminum (Al) electrodes. Operating parameters have been optimized and treatment efficiency of SS and Al electrodes have been compared by central composite design of response surface analysis in terms of COD, color and total organic carbon (TOC) removal. Individual and interactive effects of four independent parameters namely initial pH (pHo: 2-10 and 4-10 for SS and Al electrodes, respectively), current density (j: 30.86-154.32 A m(-2)), inter-electrode distance (g: 0.5-2.5 cm) and electrolysis time (t: 30-150 min) on the COD, color and TOC removal efficiency were evaluated for both the electrodes. SS electrode was found to be more effective for the removal of COD, color and TOC with removal efficiencies of 70%, 93% and 72%, respectively, as compared to Al electrode, which showed respective removal efficiencies of 59%, 80% and 55%. A two-stage EC process was also conducted to study the predominance of different types of electrodes, and to increase the efficiency of EC process. Results shows that SS followed by Al electrode (with total COD, color and TOC removal efficiency of 81%, 94% and 78%, respectively) was found to be more effective than Al followed by SS electrode combination (with total COD, color and TOC removal efficiency of 78%, 89% and 76%, respectively). Present study shows that EC process can be used as an additional step to bio-methanation process so as to meet effluent discharge standards in distilleries.


Assuntos
Alumínio/química , Eletrodos , Eletrólise/instrumentação , Recuperação e Remediação Ambiental/instrumentação , Aço Inoxidável/química , Poluentes da Água/química , Eletroquímica/métodos , Eletrólise/métodos , Recuperação e Remediação Ambiental/métodos , Desenho de Equipamento , Etanol/química , Índia , Resíduos Industriais , Purificação da Água/instrumentação , Purificação da Água/métodos
7.
Environ Sci Technol ; 48(1): 656-63, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24328192

RESUMO

Activated persulfate oxidation is an effective in situ chemical oxidation process for groundwater remediation. However, reactivity of persulfate is difficult to manipulate or control in the subsurface causing activation before reaching the contaminated zone and leading to a loss of chemicals. Furthermore, mobilization of heavy metals by the process is a potential risk. An effective approach using iron electrodes is thus developed to manipulate the reactivity of persulfate in situ for trichloroethylene (TCE) degradation in groundwater and to limit heavy metals mobilization. TCE degradation is quantitatively accelerated or inhibited by adjusting the current applied to the iron electrode, following k1 = 0.00053·Iv + 0.059 (-122 A/m(3) ≤ Iv ≤ 244 A/m(3)) where k1 and Iv are the pseudo first-order rate constant (min(-1)) and volume normalized current (A/m(3)), respectively. Persulfate is mainly decomposed by Fe(2+) produced from the electrochemical and chemical corrosion of iron followed by the regeneration via Fe(3+) reduction on the cathode. SO4(•-) and ·OH cocontribute to TCE degradation, but ·OH contribution is more significant. Groundwater pH and oxidation-reduction potential can be restored to natural levels by the continuation of electrolysis after the disappearance of contaminants and persulfate, thus decreasing adverse impacts such as the mobility of heavy metals in the subsurface.


Assuntos
Eletrólise , Tricloroetileno/química , Poluentes Químicos da Água/química , Eletrodos , Eletrólise/instrumentação , Eletrólise/métodos , Água Subterrânea/química , Concentração de Íons de Hidrogênio , Ferro , Metais Pesados/química , Oxirredução , Sulfatos/química
8.
Bull Acad Natl Med ; 198(4-5): 867-79, 2014.
Artigo em Francês | MEDLINE | ID: mdl-26753412

RESUMO

Consumption of alkaline reduced water produced by domestic electrolysis devices was approved in Japan in 1965 by the Minister of Health, Work and Wellbeing, for the treatment of gastrointestinal disorders. Today, these devices are also freely available in France. The commercial information provided with the devices recommends the consumption of 1 to 1.5 liters per day, not only for gastrointestinal disorders but also for numerous other illnesses such as diabetes, cancer and inflammation. Academic research on this subject has been undergoing in Japan since 1990, and has established that the active ingredient is dissolved dihydrogen, which eliminates the free radical HO· in vivo. It has also been shown that electrode degradation during use of the devices releases highly reactive platinum nanoparticles, the toxicity of which is unknown. The authors of this report recommend alerting the French health authorities to the uncontrolled availability of these devices that generate drug substances and should therefore be subject to regulatory requirements.


Assuntos
Antioxidantes/uso terapêutico , Ingestão de Líquidos , Eletrólise/instrumentação , Utensílios Domésticos/legislação & jurisprudência , Purificação da Água , Água/efeitos adversos , Animais , Antioxidantes/química , Diabetes Mellitus/terapia , Gastroenteropatias/terapia , Humanos , Concentração de Íons de Hidrogênio , Legislação de Dispositivos Médicos , Nanopartículas/análise , Platina/análise , Risco , Água/química , Poluentes Químicos da Água/análise
9.
Ann Biol Clin (Paris) ; 71(4): 443-8, 2013.
Artigo em Francês | MEDLINE | ID: mdl-23906572

RESUMO

Sweat chloride (Cl(-)) measurement is a key step for the diagnosis of cystic fibrosis. The coulometric technique is validated in this context by international guidelines. The aim of our study was to evaluate the assay for sweat Cl(-) ions using direct potentiometry on disposable cassette (Spotchem™ SE EL-1520, Elitech-Arkray) by comparing results to those obtained on the same sample, by coulometry (Chloride analyser Sherwood 926S, Dutscher). To complete our table of correspondence between the results of Cl(-) ions and sweat conductivity (Sweat Check™ 3100), conductivity has been also achieved for 99 of the 139 sweat samples studied. Linearity of each technique performed extends from 10 to 120 mmol/L. The coefficients of variation within and between runs are < 5%. Comparison of 139 results (Passing - Bablock regression) shows a significant difference (p < 0.001): [Spotchem] = 1.026 [Chloride analyser] + 1.8, r = 0.996. After correction with regression factors, only 6 pairs of values (4.6%) had a difference greater than ± 5 mmol/L). The results of conductivity measurement is strongly correlated with those of Cl(-) ions (r = 0.959 for Chloride analyser and 0.965 for Spotchem; p = 0.576) with a linear relationship between the decision thresholds from 30 to 60 mmol/L Cl(-). Sweat Cl(-) determinations using Spotchem™ analyser meet the criteria required by analytical recommendations. The technique is standardized, easy to perform and fast. Its good practicability makes the sweat test independent to operator and allows point-of care use.


Assuntos
Cloretos/análise , Potenciometria/métodos , Suor/química , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Fibrose Cística/diagnóstico , Condutividade Elétrica , Eletrólise/instrumentação , Eletrólise/métodos , Humanos , Lactente , Eletrodos Seletivos de Íons , Pessoa de Meia-Idade , Agonistas Muscarínicos , Pilocarpina , Potenciometria/instrumentação , Adulto Jovem
11.
J Environ Sci Health B ; 47(4): 355-61, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22428897

RESUMO

Iron electrodes were used for electrocoagulation (EC) treatment of wastewater from a dairy plant. Electrolysis time, pH, current density and distance between electrodes were considered to assess the removal efficiency of chemical oxygen demand (COD), total solids (TS) and their fractions and turbidity. Samples were collected from the effluent of a dairy plant using a sampling methodology proportional to the flow. The treatments were applied according to design factorial of half fraction with two levels of treatments and three repetitions at the central point. The optimization of parameters for treating dairy industry effluent by electrocoagulation using iron electrodes showed that electric current application for 15 minutes, an initial sample pH close to neutral (pH 7.0) and a current density of 50 A (.)(m-2) resulted in a significant reduction in COD by 58 %; removal of turbidity, suspended solids and volatile suspended solids by 95 %; and a final treated effluent pH of approximately 9.5. Negative consequences of the type of electrode used were the emergence of an undesirable color and an increase in the proportion of dissolved solids in the treated effluent.


Assuntos
Eletrólise/métodos , Esgotos/química , Purificação da Água/métodos , Criação de Animais Domésticos , Animais , Análise da Demanda Biológica de Oxigênio , Eletrodos , Eletrólise/instrumentação , Concentração de Íons de Hidrogênio , Ferro/química , Purificação da Água/instrumentação
12.
Biomed Microdevices ; 14(3): 483-96, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22273985

RESUMO

We present the first implantable drug delivery system for controlled timing and location of dosing in small animals. Current implantable drug delivery devices do not provide control over these factors nor are they feasible for implantation in research animals as small as mice. Our system utilizes an integrated electrolysis micropump, is refillable, has an inert drug reservoir for broad drug compatibility, and is capable of adjustment to the delivery regimen while implanted. Electrochemical impedance spectroscopy (EIS) was used for characterization of electrodes on glass substrate and a flexible Parylene substrate. Benchtop testing of the electrolysis actuator resulted in flow rates from 1 µL/min to 34 µL/min on glass substrate and up to 6.8 µL/min on Parylene substrate. The fully integrated system generated a flow rate of 4.72 ± 0.35 µL/min under applied constant current of 1.0 mA while maintaining a power consumption of only ~3 mW. Finally, we demonstrated in vivo application of the system for anti-cancer drug delivery in mice.


Assuntos
Desenho de Equipamento/instrumentação , Bombas de Infusão Implantáveis , Sistemas Microeletromecânicos/instrumentação , Sistemas Microeletromecânicos/métodos , Microtecnologia/instrumentação , Animais , Eletrólise/instrumentação , Camundongos , Microtecnologia/métodos , Polímeros , Xilenos
13.
Med Tr Prom Ekol ; (11): 25-9, 2012.
Artigo em Russo | MEDLINE | ID: mdl-23479956
14.
IEEE Trans Biomed Eng ; 58(11): 3104-11, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21824840

RESUMO

In this paper, we present an ultrasonically powered implantable micro-oxygen generator (IMOG) that is capable of in situ tumor oxygenation through water electrolysis. Such active mode of oxygen generation is not affected by increased interstitial pressure or abnormal blood vessels that typically limit the systemic delivery of oxygen to hypoxic regions of solid tumors. Wireless ultrasonic powering (2.15 MHz) was employed to increase the penetration depth and eliminate the directional sensitivity associated with magnetic methods. In addition, ultrasonic powering allowed for further reduction in the total size of the implant by eliminating the need for a large area inductor. IMOG has an overall dimension of 1.2 mm × 1.3 mm × 8 mm, small enough to be implanted using a hypodermic needle or a trocar. In vitro and ex vivo experiments showed that IMOG is capable of generating more than 150 µA which, in turn, can create 0.525 µL/min of oxygen through electrolytic disassociation. In vivo experiments in a well-known hypoxic pancreatic tumor models (1 cm (3) in size) also verified adequate in situ tumor oxygenation in less than 10 min.


Assuntos
Eletrólise/instrumentação , Eletrônica Médica/instrumentação , Hipóxia/terapia , Oxigênio/metabolismo , Ultrassom/métodos , Animais , Engenharia Biomédica , Eletrônica Médica/métodos , Desenho de Equipamento , Humanos , Substâncias Luminescentes , Camundongos , Camundongos Nus , Microtecnologia/instrumentação , Modelos Biológicos , Oxigênio/química , Neoplasias Pancreáticas/cirurgia , Neoplasias Pancreáticas/terapia , Reprodutibilidade dos Testes , Microambiente Tumoral/fisiologia , Ultrassom/instrumentação , Água/metabolismo
15.
Water Sci Technol ; 63(3): 484-90, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21278471

RESUMO

Using a self-made Pd/C gas-diffusion electrode as the cathode and a Ti/IrO2/RuO2 anode, the degradation of 4-chlorophenol has been investigated in an undivided electrolysis device by the electrochemical oxidation processes. The result indicated that the neutral aqueous solutions can accelerate 4-chlorophenol degradation during electrolysis. The removal efficiency of 4-chlorophenol and COD reached about 89.6% and 62.0% after 120 min electrolysis, respectively. It suggested that most of 4-chlorophenol was oxidised to intermediates using the Pd/C gas-diffusion electrode. Furthermore, the biodegradation ability of the solution was increased significantly during the electrolysis. The degradation of 4-chlorophenol was attributed to the cooperative oxidation processes including electrochemical oxidation at the anode and H2O2 and hydroxyl radical (HO·) produced by the reduction of oxygen at the cathode. Finally, main aromatic intermediates (e.g., hydroquinone and benzoquinone) and main aliphatic carboxylic intermediates (e.g., oxalic, malonic, maleic, succinic, fumaric, and dodecanoic acids) were identified by GC-MS. Moreover, a reaction scheme involving all these intermediates was proposed.


Assuntos
Carbono/química , Clorofenóis/isolamento & purificação , Eletrólise/métodos , Gases/química , Peróxido de Hidrogênio/química , Paládio/química , Análise da Demanda Biológica de Oxigênio , Catálise/efeitos da radiação , Clorofenóis/química , Difusão/efeitos da radiação , Eletrodos , Eletrólise/instrumentação , Concentração de Íons de Hidrogênio/efeitos da radiação , Oxirredução/efeitos da radiação , Soluções , Raios Ultravioleta
16.
Huan Jing Ke Xue ; 31(6): 1506-12, 2010 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-20698264

RESUMO

Using a self-made Pd/C gas-diffusion electrode as the cathode and Ti/IrO2/RuO2 as the anode, the degradation of phenol was investigated in an undivided electrolysis device by the electrochemical oxidation process. Hydroxyl radical (*OH) was determined in the reaction mixture by the electron spin resonance spectrum (ESR). The result indicated that the Pd/C catalyst in Pd/C gas-diffusion electrode system accelerated the two-electron reduction of O2 to H2O2 when feeding air, which is in favor of producing *OH. After 120 min electrolysis in Pd/C gas-diffusion electrode system, the steady concentration of H2O2 was 7.5 mg/L. The removal efficiency of phenol and COD reached about 97.2% and 50% after 120 min electrolysis, respectively, which suggested that most of phenol were oxidized to intermediates using the Pd/C gas-diffusion electrode. Furthermore, the ratio of BOD5/COD of the solutions was 9.1 times larger than the initial ones. Hence the electrochemical oxidation can enhance the biodegradation character of the phenol solution. The degradation of phenol was supposed to be cooperative oxidation by direct and/or indirect electrochemical oxidation at the anode and H2O2, *OH produced by oxygen reduction at the cathode. UV-Vis and GC-MS identified catechol, hydroquinone, and benzoquinone as the main aromatic intermediates, and adipic, maleic, fumaric, succinic, malonic, and oxalic acids as the main aliphatic carboxylic intermediates. A reaction scheme involving all these intermediates was proposed.


Assuntos
Eletrodos , Eletrólise/métodos , Peróxido de Hidrogênio/química , Paládio/química , Fenol/isolamento & purificação , Catálise , Difusão , Eletroquímica , Eletrólise/instrumentação , Gases/química , Fenol/química , Poluentes Químicos da Água/química , Poluentes Químicos da Água/isolamento & purificação
17.
Environ Sci Technol ; 43(6): 2179-83, 2009 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-19368232

RESUMO

Microbial electrolysis cells (MECs) are an efficient technology for generating hydrogen gas from organic matter, but alternatives to precious metals are needed for cathode catalysts. We show here that high surface area stainless steel brush cathodes produce hydrogen at rates and efficiencies similar to those achieved with platinum-catalyzed carbon cloth cathodes in single-chamber MECs. Using a stainless steel brush cathode with a specific surface area of 810 m2/m3, hydrogen was produced at a rate of 1.7 +/- 0.1 m3-H2/m3-d (current density of 188 +/- 10 A/m3) at an applied voltage of 0.6 V. The energy efficiency relative to the electrical energy input was 221 +/- 8%, and the overall energy efficiency was 78 +/- 5% based on both electrical energy and substrate utilization. These values compare well to previous results obtained using platinum on flat carbon cathodes in a similar system. Reducing the cathode surface area by 75% decreased performance from 91 +/- 3 A/m3 to 78 +/- 4 A/m3. A brush cathode with graphite instead of stainless steel and a specific surface area of 4600 m2/m3 generated substantially less current (1.7 +/- 0.0 A/m3), and a flat stainless steel cathode (25 m2/m3) produced 64 +/- 1 A/m3, demonstrating that both the stainless steel and the large surface area contributed to high current densities. Linear sweep voltammetry showed that the stainless steel brush cathodes both reduced the overpotential needed for hydrogen evolution and exhibited a decrease in overpotential over time as a result of activation. These results demonstrate for the first time that hydrogen production can be achieved at rates comparable to those with precious metal catalysts in MECs without the need for expensive cathodes.


Assuntos
Fontes de Energia Bioelétrica , Eletrodos , Eletrólise/instrumentação , Aço Inoxidável , Bactérias/metabolismo , Eletrólise/métodos , Hidrogênio/metabolismo , Platina
18.
Chemosphere ; 72(4): 659-65, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18423519

RESUMO

We recently reported a system for inactivating antineoplastics in which sodium hypochlorite is supplied by the electrolysis of sodium chloride solution. In this study, we designed an electrolysis apparatus for inactivating the cytotoxicity of antineoplastics in clinical wastewater using the system. The apparatus consists of an electrolysis cell with platinum-iridium electrodes, a pool tank, a circulating system for wastewater, a safety system for explosive gas and overflow, and an exhaust duct. The free chlorine concentration increased linearly up to 6500 mg l(-1), and pH also increased to 9.0-10.0 within 2h, when 0.9% sodium chloride solution was electrolyzed. We examined its efficacy with model and clinical wastewaters. The reciprocal of dilution factor for disappearance of cytotoxicity using Molt-4 cells was compared before and after electrolysis. In the model wastewater, that was 9.10 x 10(4) before electrolysis, and 3.56 x 10(2) after 2h of electrolysis. In the clinical wastewater (n=26), that was 6.90 x 10(3)-1.02 x 10(6) before electrolysis, and 1.08 x 10(2)-1.45 x 10(4) after 2h of electrolysis. Poisonous and explosive gases released by the electrolysis were measured; however, they were found to be negligible in terms of safety. The environmental load was evaluated by carbon dioxide generation as an index and it was found that the carbon dioxide generated by the electrolysis method was 1/70 lower than that by the dilution method with tap water. Moreover, the cost of the electrolysis method was 1/170 lower than that of the dilution method. This method was found to be both effective and economically valuable.


Assuntos
Antineoplásicos/química , Antineoplásicos/toxicidade , Eletrólise/instrumentação , Hospitais , Esgotos/química , Gerenciamento de Resíduos/instrumentação , Dióxido de Carbono/química , Custos e Análise de Custo , Eletrólise/economia , Poluentes Ambientais/química , Poluentes Ambientais/toxicidade , Gases/química , Oxirredução , Reprodutibilidade dos Testes , Gerenciamento de Resíduos/economia
19.
Nucl Med Biol ; 35(2): 245-53, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18312836

RESUMO

UNLABELLED: 90 Y of high specific activity and very high radionuclidic purity (>99.998%) is essential for targeted therapy. Since the current methods used for the preparation of 90 Y from 90 Sr are not adaptable for use in a central/hospital radiopharmacy, a simple 90 Sr-90 Y generator system based on electrochemical separation technique was developed. METHODS: Two-cycle electrolysis procedure was developed for separation of 90 Y from 90 Sr in nitrate solution. The first electrolysis was performed for 90 min in 90 Sr(NO3)2 feed solution at pH 2-3 at a potential of -2.5 V with 100-200 mA current using platinum electrodes. The second electrolysis was performed for 45 min in 3 mM HNO3 at a potential of -2.5 V with 100 mA current. In this step, the cathode from the first electrolysis containing 90 Y was used as anode along with a fresh circular platinum electrode as cathode. The 90 Y deposited on the circular cathode after the second electrolysis was dissolved in acetate buffer to obtain 90 Y acetate, suitable for radiolabeling. RESULTS: >96% recovery of 90 Y could be achieved in each cycle, with an overall decay corrected yield of >90%. The recovered 90 Y had high radionuclidic purity with barely 30.2+/-15.2 kBq (817+/-411 nCi) of 90 Sr per 37 GBq (1 Ci) of 90 Y (0.817+/-0.411 ppm). Consistent and repeated separation could be demonstrated using up to 1.85 GBq (50 mCi) of 90 Sr. The generator was named "Kamadhenu," the eternally milk-yielding Indian mythological cow. CONCLUSIONS: A technique suitable for adaptation at central radiopharmacies for obtaining therapeutic quantities of pure 90 Y has been developed.


Assuntos
Eletrólise/instrumentação , Desenho de Equipamento/instrumentação , Radioisótopos de Estrôncio/química , Radioisótopos de Ítrio/química , Fracionamento Químico/métodos , Eletrodos , Eletrólise/métodos , Soluções Farmacêuticas/análise , Soluções Farmacêuticas/química , Radioisótopos de Estrôncio/análise , Radioisótopos de Ítrio/análise
20.
J Hazard Mater ; 150(1): 166-73, 2008 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-17945416

RESUMO

Treatment of real reactive dyebath effluent comprising of an exhausted reactive dyebath and its sequential rinses with electrocoagulation (EC) using aluminum (Al) and stainless steel (SS) electrodes was investigated. The experimental study focused on the effect of applied current density (22-87 mA/cm(2); at an initial, optimum pH of 5.5) on decolorization and COD removal rates using Al and SS as electrode materials. Results have indicated that the treatment efficiency was enhanced appreciably by increasing the applied current density when Al electrodes were used for EC, whereas no clear correlation existed between current density and removal rates for EC with SS electrodes the treatment efficiency could only be improved when the applied current density was in the range of 33-65 mA/cm(2). It was established that EC with SS electrodes was superior in terms of decolorization kinetics (99-100% color removal after 10-15 min EC at all studied current densities), whereas EC with Al electrodes was more beneficial for COD removal in terms of electrical energy consumption (5 kWh/m(3) wastewater for EC with Al electrodes instead of 9 kWh/m(3) wastewater for EC with SS electrodes).


Assuntos
Alumínio/química , Corantes/química , Eletrólise/instrumentação , Eletrólise/métodos , Aço Inoxidável/química , Fibra de Algodão , Eletroquímica/métodos , Eletrodos , Eletrólise/economia , Esgotos/química , Purificação da Água/métodos
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