Análise e demonstração dos primeiros métodos de soldagem a arco por eletrodo de carvão e eletrodo metálico nu / Analysis and demonstration of the first methods of arc welding using carbon electrode and bare metal electrode

Perovskite solar cells (PSCs) with earth-abundant carbon as an effective replacer for unstable hole-transporting materials and expensive electrodes is a recently proposed structure promising better air and moisture stability. In this review paper, we report on the latest advances and state of the art of Pb-free and low-Pb-content perovskites, used as absorbers in carbon-based perovskite solar cells. The focus is on the implementation of these, environmentally friendly and non-toxic, structures in PSCs with a carbon electrode as a replacement of the noble metal electrode typically used (C-PSCs). The motivation for this study has been the great potential that C-PSCs have shown for the leap towards the commercialization of PSCs. Some of their outstanding properties include low cost, high-stability, ambient processability and compatibility with most up-scaling methods (e.g., printing). By surpassing the key obstacle of toxicity, caused by the Pb content of the highest-performing perovskites, and by combining the advantages of C-PSCs with the Pb-free perovskites low toxicity, this technology will move one step further; this review summarizes the most promising routes that have been reported so far towards that direction.

Download Full-text

Arc welding

AccessScience ◽

10.1036/1097-8542.047100 ◽

2015 ◽

Keyword(s):

Arc Welding

Download Full-text

Unprotected Left Main Coronary Artery Percutaneous Coronary Intervention-Our Experiences at a Tertiary Hospital

Cardiovascular Journal ◽

10.3329/cardio.v6i2.18349 ◽

2014 ◽

Vol 6 (2) ◽

pp. 107-111

Author(s):

S Munwar ◽

AHMW Islam ◽

S Talukder ◽

AQM Reza ◽

T Ahmed ◽

...

Keyword(s):

Percutaneous Coronary Intervention ◽

Coronary Artery ◽

Left Main Coronary Artery ◽

Coronary Intervention ◽

Drug Eluting Stent ◽

Bare Metal ◽

Coronary Artery Diseases ◽

Left Main ◽

Percutaneous Coronary ◽

Drug Eluting

Background: Aim of the study was to evaluate the primary procedural success of percutaneous coronary intervention of unprotected left main coronary artery stenosis using either Bare-metal stents or drug eluting stent. Methods: Total 33 patients were enrolled in this very preliminary non-randomized prospective cohort study. Among them, Male: 25 and Female: 8. Total 35 stents were deployed. Mean age were for Male: 59 yrs, for Female: 62 yrs. Associated coronary artery diseases risk factors were dyslipidemia, High Blood pressure, Diabetes Mellitus, Positive family history for coronary artery diseases and smoking. Results: Among the study group; 26 (78%) were Dyslipidemic, 24(70%) were hypertensive; 17 (51.5%) patients were Diabetic, 11(33%) were smoker and 7(21%) patients had family history of Ischaemic heart disease. Female patients were more obese (BMI M 26: F 27) and developed coronary artery diseases in advance age. Common stented territory were left main: 20 (60%), Left main to left anterior descending artery 7 (22%) and Left main to left circumflex artery 6 (18%). Average length and diameter of stent was 3.5 and 18 mm respectively. Stent used: Bare Metal Stent 5 (15%), Drug Eluting Stent: 28 (85%). Among the different Drug Eluting Stents, Everolimus eluting stents were 11 (39.3%), Sirolimus eluting 10(35.7%), Paclitaxel eluting 3 (10.7%), Biolimus eluting 3 (10.7%) and Zotarolimus eluting1 (3.6%). In the present study, overall survival outcome was 94% (31 patient), mortality of cardiac cause 3% (1 patient) and 1 patient (3%) died of hepatocellular carcinoma. Conclusion: Our study has shown that percutaneous coronary intervention of the unprotected left main is a safe and effective alternative to Coronary Artery Bypass Graft (CABG). DOI: http://dx.doi.org/10.3329/cardio.v6i2.18349 Cardiovasc. j. 2014; 6(2): 107-111

Download Full-text