Printed Circuit Boards
Mostrando 1-12 de 19 artigos, teses e dissertações.
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1. PROCESSING OF A METAL CONCENTRATE FROM GROUND WASTE PRINTED CIRCUIT BOARDS IN ACIDIC MEDIA USING HYDROGEN PEROXIDE AS OXIDANT
The recovery of precious and base metals of a metal concentrate from ground waste printed circuit boards (PCBs) is described in detail. Samples were treated with NaOHaq. to remove the soldering mask. Experiments were performed in acidic medium (HF, H2SO4, CH3COOH or H3PO4) using H2O2 as oxidant. Base metals were leached in high yields (>99 wt.%) at ~40 ºC a
Quím. Nova. Publicado em: 20/07/2020
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2. Evaluation of Mass Loss in Different Stages of Printed Circuit Boards Recycling Employed in Temperature Controllers
The aim of this work was to evaluate mass loss in each stage of the recycling process for metal recovery from PCBs of controllers and temperature indicators of cold chambers. The stages of process consists of grinding, particle size classification, magnetic and electrostatic separation. It was analyzed 13 kg of PCBs. These PCBs were crushed and ground. The g
Mat. Res.. Publicado em: 02/12/2019
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3. A new and improved electric fish finder with resources for printed circuit board fabrication
RESUMO Nós descrevemos o projeto de circuitos eletrônicos e as instrucões para a construção e uso de um detector de peixes elétricos portátil (bio-amplificador diferencial de banda-larga com acoplamento AC). Este aparelho permite a detecção e o monitoramento das descargas de órgãos elétricos gerados por peixes neotropicais da ordem Gymnotiformes
Neotrop. ichthyol.. Publicado em: 25/11/2019
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4. Enrichment of Copper, Lead, and Tin by Mechanical Dry Processing of Obsolete Printed Circuit Board Residues
Waste printed circuit boards (WPCB) residues were mechanically processed to concentrate their metal content aiming to reduce costs of the subsequent recovery of copper, tin, and lead. A fully dry route was proposed to avoid the generation of liquid effluents that would require additional treatment. Firstly, 10.7% of the residue was segregated by magnetic sep
Mat. Res.. Publicado em: 24/10/2019
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5. An Enhanced Random Vibration and Fatigue Model for Printed Circuit Boards
Abstract Aerospace vehicles are mostly exposed to random vibration loads during its operational lifetime. These harsh conditions excites vibration responses in the vehicles printed circuit boards, what can cause failure on mission functionality due to fatigue damage of electronic components. A novel analytical model to evaluate the useful life of embedded el
Lat. Am. j. solids struct.. Publicado em: 2017
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6. Modelling of Lead Migration from Electronic Waste to Mixtures of Kaolinite, Iron Oxides and Organic Matter
Improper disposal of electronic waste in the environment facilitates migration of heavy metals, especially lead, into the soil and can contribute to the bioavailability of this species. Based on a simplex-centroid mixture experimental design, small-scale tests were performed for incubation of printed circuit boards (PCBs) in mixtures containing organic matte
J. Braz. Chem. Soc.. Publicado em: 2016-05
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7. Bioleaching of gold, copper and nickel from waste cellular phone PCBs and computer goldfinger motherboards by two
Aspergillus niger strainsIn an effort to develop alternate techniques to recover metals from waste electrical and electronic equipment (WEEE), this research evaluated the bioleaching efficiency of gold (Au), copper (Cu) and nickel (Ni) by two strains of
Aspergillus niger in the presence of gold-plated finger integrated circuits found in computer motherboards (GFIBraz. J. Microbiol.. Publicado em: 2015-09
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8. Processamento de placas de circuito impresso de equipamentos eletroeletrônicos de pequeno porte
A hydrometallurgical process applicable to printed circuit boards of small electrical and electronic devices was developed. This involved three leaching steps (60 ºC, 2 h): 6 mol L-1 NaOH, 6 mol L-1 HCl and aqua regia. NaOH removed the resin and flame retardant that covered the circuit boards. HCl dissolved the most electropositive metals and a small amount
Quím. Nova. Publicado em: 2013
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9. Incorporação de resíduos de placas de circuitos impressos (RPCI) em massas cerâmicas triaxiais utilizando experimentos com misturas / Incorporation of waste printed circuit boards (WPCB) in triaxial ceramic bodies using experiments with mixtures
The aim of this work is evaluate the effect of incorporation of waste printed circuit boards (WPCB) in physical and mechanical properties of triaxial ceramics for coating. Through the technique of experiment with mixtures seven formulations were developed with clay (40, 53, 60 e 80%); phyllite (20, 33, 40 e 60%) and waste (0, 14, 20 e 40%). The WPCB was char
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 15/02/2012
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10. Conjugate Cooling of a Discrete Heater in Laminar Channel Flow
Electronic components are usually assembled on printed circuit boards cooled by forced airflow. When the spacing between the boards is small, there is no room to employ a heat sink on critical components. Under these conditions, the components’ thermal control may depend on the conductive path from the heater to the board in addition to the direct convecti
Journal of the Brazilian Society of Mechanical Sciences and Engineering. Publicado em: 2011-09
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11. Recuperação de metais a partir do processamento mecânico e hidrometalúrgico de placas de circuito impresso de celulares obsoletos. / Metals recovery from mechanical and hydrometalurgy processing of printed circuit boards from obsolete mobile.
O avanço da tecnologia de aparelhos eletro-eletrônicos favorece a troca constante dos equipamentos. O freqüente descarte de aparelhos obsoletos se torna um problema de sustentabilidade e também um problema ambiental devido ao seu acúmulo em aterros. A solução para minimizar estes impactos é a reciclagem de seus componentes. Por esta razão, o princip
Publicado em: 2010
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12. Utilização de processos mecânicos e eletroquímicos para reciclagem de cobre de sucatas eletrônicas = Use of mechanical and electrochemical process for recycling of copper from electronic scraps / Use of mechanical and electrochemical process for recycling of copper from electronic scraps
O crescimento constante na geração de resíduos sólidos em todo o mundo tem estimulado estudos para os mais variados tipos de resíduos. Nesse trabalho, foram estudadas as Placas de Circuito Impresso (PCI), que fazem parte das sucatas eletrônicas e que são encontradas nos equipamentos eletroeletrônicos. As PCI são compostas de polímeros, cerâmicos e
Publicado em: 2010