26 research outputs found

    Effect of chemical structure on the cloud point of some new non-ionic surfactants based on bisphenol in relation to their surface active properties

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    AbstractA series of non-ionic surfactants were prepared from bisphenol derived from acetone (A), acetophenone (AC) and cyclohexanone (CH). The prepared bisphenols were ethoxylated at different degrees of ethylene oxide (27, 35, 43). The ethoxylated bisphenols were non-esterified by fatty acids; decanoic, lauric, myristic, palmitic, stearic, oleic, linoloic and linolinic. Some surface active properties for these surfactants were measured and calculated such as, surface tension [γ], critical micelle concentration [CMC], minimum area per molecule [Amin], surface excess [Cmax], free energy of micellization and adsorption [ΔGmic] and [ΔGads]. At a certain temperature, the cloud point was measured for these surfactants. From the obtained data it was found that; the cloud point is very sensitive to the increase of the alkyl chain length, content of ethylene oxide and degree of unsaturation. The core of bisphenol affected the cloud point sharply and they are ranked regarding bisphenol structure as BA>BCH>BAC. By inspection of the surface active properties of these surfactants, a good relation was obtained with their cloud points. The data were discussed on the light of their chemical structures

    Acute Coronary Syndrome and Ischemic Heart Disease in Pregnancy: Data From the EURObservational Research Programme-European Society of Cardiology Registry of Pregnancy and Cardiac Disease

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    Background The prevalence of ischemic heart disease (IHD) in women of child-bearing age is rising. Data on pregnancies however are scarce. The objective is to describe the pregnancy outcomes in these women. Methods and Results The European Society of Cardiology-EURObservational Research Programme ROPAC (Registry of Pregnancy and Cardiac Disease) is a prospective registry in which data on pregnancies in women wit

    Risk profiles and one-year outcomes of patients with newly diagnosed atrial fibrillation in India: Insights from the GARFIELD-AF Registry.

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    BACKGROUND: The Global Anticoagulant Registry in the FIELD-Atrial Fibrillation (GARFIELD-AF) is an ongoing prospective noninterventional registry, which is providing important information on the baseline characteristics, treatment patterns, and 1-year outcomes in patients with newly diagnosed non-valvular atrial fibrillation (NVAF). This report describes data from Indian patients recruited in this registry. METHODS AND RESULTS: A total of 52,014 patients with newly diagnosed AF were enrolled globally; of these, 1388 patients were recruited from 26 sites within India (2012-2016). In India, the mean age was 65.8 years at diagnosis of NVAF. Hypertension was the most prevalent risk factor for AF, present in 68.5% of patients from India and in 76.3% of patients globally (P < 0.001). Diabetes and coronary artery disease (CAD) were prevalent in 36.2% and 28.1% of patients as compared with global prevalence of 22.2% and 21.6%, respectively (P < 0.001 for both). Antiplatelet therapy was the most common antithrombotic treatment in India. With increasing stroke risk, however, patients were more likely to receive oral anticoagulant therapy [mainly vitamin K antagonist (VKA)], but average international normalized ratio (INR) was lower among Indian patients [median INR value 1.6 (interquartile range {IQR}: 1.3-2.3) versus 2.3 (IQR 1.8-2.8) (P < 0.001)]. Compared with other countries, patients from India had markedly higher rates of all-cause mortality [7.68 per 100 person-years (95% confidence interval 6.32-9.35) vs 4.34 (4.16-4.53), P < 0.0001], while rates of stroke/systemic embolism and major bleeding were lower after 1 year of follow-up. CONCLUSION: Compared to previously published registries from India, the GARFIELD-AF registry describes clinical profiles and outcomes in Indian patients with AF of a different etiology. The registry data show that compared to the rest of the world, Indian AF patients are younger in age and have more diabetes and CAD. Patients with a higher stroke risk are more likely to receive anticoagulation therapy with VKA but are underdosed compared with the global average in the GARFIELD-AF. CLINICAL TRIAL REGISTRATION-URL: http://www.clinicaltrials.gov. Unique identifier: NCT01090362

    Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

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    Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

    Organized Chaos: Informal Institution Building among Palestinian Refugees in the Maashouk Gathering in South Lebanon

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    Contains fulltext : 215912.pdf (publisher's version ) (Closed access) Contains fulltext : 215912a.pdf (author's version ) (Closed access)Informal institutions are increasingly recognized as a core concept in our understanding of the organization of socio-political life in refugee communities. This article contributes to this understanding by exploring the ways in which urban refugees in the Palestinian informal community, known as gathering, of Maashouk create, reconfigure and contest informal institutions in their quest to access basic urban services such as electricity, water, waste management and shelter maintenance. In particular, the findings generated through an innovative process mapping methodology suggest that informal institutions do not merely complement and challenge existing formal institutions, but also portend future ones. Formalization of service delivery, however, is complicated by the fact that current informality does not merely stem from residents’ coping mechanisms, but also from Lebanese state officials’ nascence of how to deal with people who are neither citizens nor residents of UN-administered refugee camps.27 juli 201

    Organized Chaos: Informal Institution Building among Palestinian Refugees in the Maashouk Gathering in South Lebanon

    No full text
    Informal institutions are increasingly recognized as a core concept in our understanding of the organization of socio-political life in refugee communities. This article contributes to this understanding by exploring the ways in which urban refugees in the Palestinian informal community, known as gathering, of Maashouk create, reconfigure and contest informal institutions in their quest to access basic urban services such as electricity, water, waste management and shelter maintenance. In particular, the findings generated through an innovative process mapping methodology suggest that informal institutions do not merely complement and challenge existing formal institutions, but also portend future ones. Formalization of service delivery, however, is complicated by the fact that current informality does not merely stem from residents’ coping mechanisms, but also from Lebanese state officials’ nascence of how to deal with people who are neither citizens nor residents of UN-administered refugee camps

    Synthesis of non-ionic surfactants based on alkylene diamine and evaluation of their corrosion inhibition efficiency on carbon steel in formation water

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    The inhibitive effects of newly synthesized non-ionic surfactant based on alkylene diamine surfactants on X-65 carbon steel in formation water was investigated by means of electrochemical techniques and quantum chemical study. These derivatives were characterized by FT-IR, and the surface tension and thermodynamic parameters were calculated. The polarization showed that the inhibition efficiency of the prepared compounds was increased with increasing the length of the internal alkyl chain between the two terminal amino groups of diamine. The electronic properties obtained using quantum chemical approach were correlated with the experimental inhibition efficiencies. The surface morphology of carbon steel was investigated using SEM

    Resolution of water in crude oil emulsion by some novel aromatic amine polyesters

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    In this work, three aromatic amines (p-toluidine, p-nitroaniline and p-chloroaniline) were chosen as bases for the repatriation of some nonionic polyesters. These amines were ethoxylated with different total number of ethylene oxide units 6, 12, 18. The prepared ethoxylated amine diols were polyesterified with maleic anhydride and polypropylene oxide polyethylene oxide block copolymers in polyesterification reaction. The demulsification efficiency of these demulsifiers was investigated using the bottle test. The effects of the molecular weight, concentration, asphaltene content, water content, Hydrophile Lipophile Balance (HLB) and temperature on the demulsification efficiency were investigated. The surface active properties were correlated with their demulsification efficiency. It was found that, NAE18D gave the best result in the demulsification process. The demulsification efficiency was discussed on the light of surface active properties, interfacial tension and the factors affecting the demulsification. The surface-active properties of the prepared demulsifiers were measured at 60 °C

    Demulsification of W/O emulsion at petroleum field and reservoir conditions using some demulsifiers based on polyethylene and propylene oxides

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    In this work, polymer molecules of alkene oxides diesters with varying HLB values and molecular weights (ED1, ED2, ED3, PD1, PD2 and PD3) were synthesized, elsewhere (Alsabagh et al., 2016). The demulsification efficiency was evaluated at field and reservoir conditions. At field conditions (60 °C and 1 atm) the data revealed that the maximum demulsification efficiency was obtained by ED3 and PD3 at 60 °C, 600 ppm after 55 and 40 min, respectively. At reservoir conditions (85 °C and 5000 psi), the PD3 and ED3 showed also the maximum demulsification efficiency was 76% and 70%, respectively, in spite of the 2% from the blank emulsion (12% BS&W) separated after 7 days. The interfacial tension (IFT) at the crude oil/water interface was measured for PD3 and ED3. From the results, it was found that the values of IFT were 0.7 and 0.8 mN m−1 respectively. The rheological behavior of the same demulsifiers was investigated. The results showed that the demulsifiers PD3 and ED3 enhance the dynamic viscosities (3.9 and 3.8 mPa s, respectively) and the (τB) yield values were 0.77 and 1.23 Pa s, respectively at temperature 85 °C, whereas, they were 3.95 mPa s and 1.5 Pa s for the blank emulsion sample

    Preparation of some thermal stable polymers based on diesters of polyethylene and polypropylene oxides macro monomers to use as surfactants at high temperature and pressure

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    Based on polyethylene (PE) and polypropylene (PP) oxides, six macromonomers were prepared through two steps. The first step was esterification of the PE and PP oxides, with oleic acid to give the corresponding monoesters. The second was the diesterfication of the prepared monoesters with methacrylic acid to give the corresponding diesters. The prepared macromonomers (diesters) were polymerized to obtain six polymers. The chemical structure of the prepared mono- and diesters and polymers was justified by IR, NMR, GPC and TGA. The obtained results confirmed that the prepared polymers have a high thermal stability and can be used in high pressure and temperature during the drainage of the water from water-in-oil emulsions. The surface active and thermodynamics parameters of these polymers in non-aqueous solution were also investigated and it was found that, these materials have high thermal stability which leads to the possibility to be used under severe reservoir conditions as surfactants
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