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Increased carbon dioxide (CO2) emissions from anthropogenic activities are a contributing factor to the growing global warming worldwide. The economical method to recover and effectively reuse CO2 is through adsorption and absorption. In this study, CO2 is absorbed into the solution of sodium hydroxide having various concentrations (0.01, 0.1, 0.5, 1.0, 3.0 and 5.0 N), and the impact of the solution pH on the various product formation was observed. The resultant products formed at different pH of the absorbing solution are sodium carbonate at pH 10, Trona at pH 9, and sodium hydrogen carbonate at pH 8. The products formed are confirmed through X-ray diffraction analysis. After pH optimization, the sodium hydrogen carbonate formed at pH 8 is converted into sodium formate through hydrogenation in the presence of nickel ferrite catalyst at 80 °C and atmospheric pressure. The sodium formate produced is then used as a precursor to synthesize formic acid upon simple reaction with sulfuric acid. A reaction % age yield of 79 ± 0.2% formic acid is noted. Condensed formic acid vapors are later analyzed, using a high performance liquid chromatography for the qualitative analysis.

Background Mitral regurgitation (MR) is commonly observed following acute myocardial infarction (MI). Localised left ventricular (LV) remodelling in the region of papillary muscles together with impaired myocardial contractility promote MR. There is a paucity of long-term follow-up studies to determine whether the severity of MR observed post-MI, changes with time. Purpose This study retrospectively followed up patients with MR detected following acute MI (AMI) to investigate changes in MR severity with time and assess for pre-discharge predictors of MR regression or progression. Methods Clinical records of 1000 patients admitted with AMI between 2016 and 2017 to a single centre were retrospectively interrogated. One hundred and nine patients met the inclusion criteria of MR on pre-discharge transthoracic echocardiography (TTE) and follow-up TTE scans. Echocardiographic parameters were investigated to determine predictors of progression or regression at follow-up. Patients were divided according to those who had early follow-up TTE (within 1-year) and late follow-up TTE (beyond 1-year). Results Early follow-up TTE was performed in 73 patients at a median of 6 (IQR 3–9) months. Patients had a mean age of 69±13 years and were predominantly male 50/73 (68%). At baseline, relative MR severities were: 49/73 (67%) mild MR, 23/73 (32%) moderate MR and 1 (1%) severe MR. At follow-up, MR had completely resolved in 18/73 (23%) patients, while 39/73 (53%) had mild MR, 15/73 (21%) moderate MR and 1 (1%) severe MR. Compared to patients with no resolution of MR, those with completel resolution were younger (mean age 62±16 vs 72±11 years; p=0.015) but there were no other significant differences between the groups. Resolution at early follow-up did not significantly influence long-term mortality rates. Late follow-up TTE was performed in 69 patients at a median 2.4 (IQR 2–3.2) years. Pre-discharge, 49/69 (71%) patients had mild MR and 20/69 (29%) moderate MR. At follow-up, MR had completely resolved in 18/69 (26%), and amongst patients with persistent MR, proportion of severities were: 37/69 (54%) mild MR, 11/69 (16%) moderate MR and 3/69 (4%) severe MR. Patients with progression of mild MR were more likely to have lower left ventricular ejection fraction (LVEF: 47±15 vs 57±12%; p=0.010) and greater indexed left ventricular end-systolic volume (LVESVi: 37±23 vs 25±14 ml/m2; p Conclusion MR observed following AMI completely resolved in approximately one-quarter of patients at 6-month and 2-year follow-up. Progression of mild MR at long-term follow-up appears to be associated with increased mortality and is predicted by lower LVEF and greater LVESVi pre-discharge. Funding Acknowledgement Type of funding sources: None.

Data were collected on patients admitted to the Queen Elizabeth Hospital Birmingham with type-1 myocardial infarction during 2016 and 2017 inclusively, who were treated by percutaneous intervention and had pre-discharge transthoracic echocardiography. The data were obtained from prospectively maintained hospital databases and records. Echocardiography was performed and reported contemporaneously by accredited echocardiographers. The purpose was to understand the prevalence and characteristics of mitral regurgitation (MR) after acute MI, including patients with ST-elevation (STEMI) and non-ST elevation MI (NSTEMI). MR was observed in 294/1000 patients with the following relative severities: mild = 76%, moderate = 21%, severe = 3% [1]. MR was graded by multiparametric quantification including proximal isolvelocity surface area (PISA), vena contracta (VC), effective regurgitant orifice area (EROA) and regurgitant volume (RVol). Amongst all patients with MR (n=294), PISA was performed in 89/294 (30%), VC 75/294 (26%), EROA in 53/294 (18%) and RVol in 26/294 (9%). Amongst patients with moderate or severe MR (n=70), PISA was performed in 57/70 (81%), VC in 55/70 (79%), EROA in 46/70 (66%) and RVol in 25/70 (36%). Characteristics of MR following acute MI were also assessed including frequency of reported leaflet thickness (259/294 = 88%) and mitral annular calcification (102/294 = 35%). Furthermore, the effect of MI on pre-existing MR was investigated and patients with pre-existing MR who continue to have MR after acute MI were found to have progression of MR by one grade in approximately 25% of cases. Finally, using Cox proportional hazards univariate analysis, significant factors associated with mortality in patients with MR post-MI include age (HR 1.065; 95% CI 1.035-1.096; p

Natural gas processing is very important industrial process. Major component of natural gas is methane, which is an increasingly utilized source of energy due to high thermal efficiency, while carbon dioxide act as an impurity and reduces its calorific value. In this research work, effects of nickel ferrite (NiFe2O4) and titanium dioxide (TiO2) nanoparticles on the permeation properties of carbon dioxide (CO2) and methane (CH4) in cellulose acetate/polyethylene glycol (CA/PEG) membranes have been investigated. CA/PEG and CA/PEG based mixed matrix membranes (MMMs) are fabricated by using the solution casting method. Concentrations of TiO2 and NiFe2O4 nanoparticles membranes are varied from 0 to 20 and 0 to 2 wt% respectively. Scanning electron microscope, tensile testing analysis, X-ray diffraction and thermal gravimetric analysis are used to characterize the fabricated membranes. Permeation study of these membranes has shown that in 5 wt%TiO2 MMMs, the permeability of CO2 and CH4 is increased up to 5.75 and 3.75 times as compared to pure polymer. By adding 1.5 wt% NiFe2O4 in the polymer matrix, the permeability of CO2 and CH4 has improved up to 3.46 and 2.1 times as compared to pure polymer. It has been observed that the addition of inorganic nanoparticles in a polymer matrix helps to enhance the permeability of gases but it has little effect on CH4/CO2 selectivity.

Mitral regurgitation (MR) following acute myocardial infarction (AMI) worsens prognosis and reports of prevalence vary significantly. The objective was to determine prevalence, risk factors, and outcomes related to MR following AMI. We identified 1000 consecutive patients admitted with AMI in 2016/17 treated by percutaneous coronary intervention with pre-discharge transthoracic echocardiography. MR was observed in 294 of 1000 (29%), graded as mild (n = 224 [76%]), moderate (n = 61 [21%]) and severe (n = 9 [3%]). Compared with patients without MR, patients with MR were older (70 ± 12 vs 63 ± 13 years; p0.001), with worse left ventricular ejection fraction (LVEF) (52 ± 15% vs 55 ± 11%; p0.001) and creatinine clearance (69 ± 33 ml/min vs 90 ± 39 ml/min; p0.001). They also had higher rates of hypertension (64% vs 55%; p = 0.012), heart failure (3.4% vs 1.1%; p = 0.014), previous MI (28% vs 20%; p = 0.005) and severe flow-limitation in the circumflex (50% vs 33%; p0.001) or right coronary artery (51% vs 42%; p = 0.014). Prevalence and severity of MR were unaffected by AMI subtype. Revascularization later than 72 hours from symptom-onset was associated with increased likelihood of MR (33% vs 25%; p = 0.036) in patients with non-ST elevation myocardial infarction (NSTEMI). After a mean of 3.2 years, 56 of 288 (19%) patients with untreated MR died. Age and LVEF independently predicted mortality. The presence of even mild MR was associated with increased mortality (p = 0.029), despite accounting for confounders. In conclusion, MR is observed in over one-quarter of patients after AMI and associated with lower survival, even when mild. Prevalence and severity are independent of MI subtype, but MR was more common with delayed revascularization following NSTEMI.