High performance boron removal from seawater by two-pass SWRO system with different membranes

2010 ◽  
Vol 10 (3) ◽  
pp. 327-336 ◽  
Author(s):  
Jia Xu ◽  
Xueli Gao ◽  
Guohua Chen ◽  
Linda Zou ◽  
Congjie Gao
Keyword(s):  
High Performance ◽  
Boron Concentration ◽  
Jiaozhou Bay ◽  
The Yellow Sea ◽  
World Health ◽  
Permeate Flux ◽  
Boron Removal ◽  
Term Operation ◽  
The Impact

Boron in the desalinated water produced by the seawater reverse osmosis (SWRO) system is one of the most challenging issues for drinking or irrigation water uses. In recent years, many post-treatment methods and designs for boron elimination have emerged and attracted lots of attention, but only a few cases have demonstrated high performance and economic efficiency. The main aim of this work was to evaluate the efficiency of boron removal from seawater using a two-pass SWRO system employing different RO membranes at Qingdao Jiaozhou Bay, the Yellow Sea of China. In this study, HYDRANAUTICS SWC3+ and ESPAB were chosen as the first and second pass membrane, respectively. The impact of feed properties including temperature, pH, salinity, boron concentration, and operational conditions such as feed pressure on boron rejection and permeate flux was determined. In addition, a relative long term run of the two-pass SWRO system was investigated and compared with performance of system that uses Filmtec membrane as reported in the literature. Although the pilot system in this study experienced more severe feed conditions with lower pH, higher feed boron concentrations and lower operational pressures: all potential negative factors for boron rejection, it still achieved good performance for boron reduction. The results of three-month long term operation indicated that, at optimum conditions, two-pass SWRO system at Qingdao Jiaozhou Bay achieved a high performance and stability without anti-scalants to produce permeate which has much a lower boron concentration than the World Health Organization (WHO) guideline.

scholarly journals Long-term body mass index changes in overweight and obese adults and the risk of heart failure, cardiovascular disease and mortality: a cohort study of over 260,000 adults in the UK

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Barbara Iyen ◽  
Stephen Weng ◽  
Yana Vinogradova ◽  
Ralph K. Akyea ◽  
Nadeem Qureshi ◽  
...  
Keyword(s):  
Heart Failure ◽  
Cardiovascular Disease ◽  
Body Mass Index ◽  
Cohort Study ◽  
Body Mass ◽  
World Health ◽  
Obese Adults ◽  
Bmi Trajectories ◽  
The Impact

Abstract Background Although obesity is a well-recognised risk factor for cardiovascular disease (CVD), the impact of long-term body mass index (BMI) changes in overweight or obese adults, on the risk of heart failure, CVD and mortality has not been quantified. Methods This population-based cohort study used routine UK primary care electronic health data linked to secondary care and death-registry records. We identified adults who were overweight or obese, free from CVD and who had repeated BMI measures. Using group-based trajectory modelling, we examined the BMI trajectories of these individuals and then determined incidence rates of CVD, heart failure and mortality associated with the different trajectories. Cox-proportional hazards regression determined hazards ratios for incident outcomes. Results 264,230 individuals (mean age 49.5 years (SD 12.7) and mean BMI 33.8 kg/m2 (SD 6.1)) were followed-up for a median duration of 10.9 years. Four BMI trajectories were identified, corresponding at baseline, with World Health Organisation BMI classifications for overweight, class-1, class-2 and class-3 obesity respectively. In all four groups, there was a small, stable upwards trajectory in BMI (mean BMI increase of 1.06 kg/m2 (± 3.8)). Compared with overweight individuals, class-3 obese individuals had hazards ratios (HR) of 3.26 (95% CI 2.98–3.57) for heart failure, HR of 2.72 (2.58–2.87) for all-cause mortality and HR of 3.31 (2.84–3.86) for CVD-related mortality, after adjusting for baseline demographic and cardiovascular risk factors. Conclusion The majority of adults who are overweight or obese retain their degree of overweight or obesity over the long term. Individuals with stable severe obesity experience the worst heart failure, CVD and mortality outcomes. These findings highlight the high cardiovascular toll exacted by continuing failure to tackle obesity.

Guidelines for Long-Term Operation of High Performance Submersible Motor Pumps in Mine Dewatering

2021 ◽  
Author(s):  
Sebastian Wulff ◽  
David Beck ◽  
Morris Reich ◽  
Jean Pierre Worringer ◽  
Paul Uwe Thamsen
Keyword(s):  
High Performance ◽  
Term Operation ◽  
Mine Dewatering ◽  
Submersible Motor

scholarly journals Coronavirus Pandemic: Coping with the Psychological Outcomes, Mental Changes, and the “New Normal” During and After COVID-19

2020 ◽  
pp. 07-19
Author(s):  
Hiba Takieddine ◽  
Samaa AL Tabbah
Keyword(s):  
Healthcare Providers ◽  
Well Being ◽  
World Health ◽  
Vulnerable Groups ◽  
Public Health Response ◽  
New Normal ◽  
The World ◽  
Health Organization ◽  
The Impact

Coronavirus disease 2019 (COVID-19) is a highly infectious disease that has rapidly swept across the world, inducing a considerable degree of fear, worry and concern in the population at large and among certain groups in particular, such as older adults, healthcare providers and people with underlying health conditions. Authorities around the world tried to prevent the virus spread by imposing social distancing measures, quarantining citizens and isolating infected persons. Apart from its physical impact, COVID-19 pandemic has brought numerous changes to people’s lives. It changed daily routines, caused worldwide economic crisis, increased unemployment, and placed people under emotional and financial pressures. It affected people psychologically and mentally especially in terms of emotions and cognition. During the acute crisis, everyone to varying degrees experienced fear of infection, somatic concerns, worries about the pandemic’s consequences, loneliness, depression, stress, as well as increased alcohol and drug use. As part of its public health response, the World Health Organization (WHO) has worked with partners to develop a set of new guidelines and messages that can be used to prevent, manage, and support mental and psychological well-being in different vulnerable target groups during the outbreak. Whether people like it or not, the psychological sequela of this pandemic will emerge and persist for months and years to come leading to long-term consequences. New lifestyles and “New Normals” will surely emerge. The main purpose of this review is to summarize the impact of coronavirus pandemic on the psychological and mental health of people around the world especially vulnerable groups. It also presents the relevant intervention actions and recommendations to cope efficiently and effectively with the psychological short-term and long-term outcomes, mental changes, and the “New Normal” during and after COVID-19. Keywords: COVID-19; Coronavirus, Psychological; Mental; New Normal

Numerical Modelling of a District Scale Groundwater Heat Pump Operation: Case Study from Colchester, UK

2021 ◽  
Author(s):  
Taha Sezer ◽  
Abubakar Kawuwa Sani ◽  
Rao Martand Singh ◽  
David P. Boon
Keyword(s):  
Large Scale ◽  
District Level ◽  
Thermal Plume ◽  
Injection Wells ◽  
Term Operation ◽  
Heating And Cooling ◽  
Groundwater Heat Pump ◽  
The Impact

<p>Groundwater heat pumps (GWHP) are an environmentally friendly and highly efficient low carbon heating technology that can benefit from low-temperature groundwater sources lying in the shallow depths to provide heating and cooling to buildings. However, the utilisation of groundwater for heating and cooling, especially in large scale (district level), can create a thermal plume around injection wells. If a plume reaches the production well this may result in a decrease in the system performance or even failure in the long-term operation. This research aims to investigate the impact of GWHP usage in district-level heating by using a numerical approach and considering a GWHP system being constructed in Colchester, UK as a case study, which will be the largest GWHP system in the UK. Transient 3D simulations have been performed pre-construction to investigate the long-term effect of injecting water at 5°C, into a chalk bedrock aquifer. Modelling suggests a thermal plume develops but does not reach the production wells after 10 years of operation. The model result can be attributed to the low hydraulic gradient, assumed lack of interconnecting fractures, and large (>500m) spacing between the production and injection wells. Model validation may be possible after a period operational monitoring.</p>

scholarly journals Improving the reliability of cable lines operation in hot climates

2020 ◽  
Vol 216 ◽  
pp. 01151
Author(s):  
Daniyar Bakhtiyarovich Madrakhimov ◽  
Vera Pavlovna Ivanova ◽  
Victoria Vyacheslavovna Tsypkina
Keyword(s):  
Solar Radiation ◽  
Climatic Factors ◽  
Climate Conditions ◽  
Term Operation ◽  
Asian Region ◽  
Hot Climate ◽  
Central Asian ◽  
Cable Lines ◽  
The Impact

Reliability of cable lines in hot climate is determined by the climatic characteristics of cables and wires, which include: long-term and short-term heat resistance, cold resistance, moisture resistance, resistance to cyclic exposure to temperatures and solar radiation, ozone resistance, etc. This article considers the main impacts of environmental factors: high temperatures, solar radiation, which, as practice shows, lead to irreversible deterioration of the electrical and mechanical properties of cable products. The result of climatic impacts in the Central Asian region, in hot climate conditions, is the aging of both insulation and protective coverings, which leads to irreversible change in the mechanical and electrical properties of the used polymers due to the loss of elasticity of the extruded material and its subsequent cracking, turning into cracks. The assessment of the possibility of long-term operation of the used polymer was carried out according to the polyethylene oxidation period, which determines the time of natural preservation of various types of cables during the period of their operation. The research was carried out on samples of cables stored under a canopy in wooden boxes, protected from sunlight and precipitation, by measuring criterion parameters with strict compliance with the established norms. Thus, the proposed solution for increasing the reliability of cable lines consists of debugging the technological process of applying insulation and sheathing, in which the extrusion of the polymer mass is carried out by technique that minimizes the ingress of contamination. Review of the results showed that extrusion line improvement would provide possibility of increasing reliability in the operation of cable products under the impact of climatic factors of the Central Asian region due to the reduced aging of insulation.

Applications of nanomaterials in corrosion protection coatings and inhibitors

2020 ◽  
Vol 38 (1) ◽  
pp. 67-86 ◽  
Author(s):  
Ahmed A. Farag
Keyword(s):  
Polymer Coating ◽  
High Performance ◽  
Surface Hardness ◽  
Metal Corrosion ◽  
Corrosive Solution ◽  
Corrosion Resistant Coatings ◽  
The Impact ◽  
Control Corrosion ◽  
Weak Resistance

AbstractVarious methodologies are practically used to control corrosion. Coatings are the most widely used to protect metals against corrosion. However, due to the weak resistance of polymer coating against the penetration of corrosive solution to the metal/coating interface, the long-term corrosion resistance of the polymer coating is reduced gradually. Recently, nanoparticles have been added to coatings to improve their chemical, mechanical and optical properties. Nanocoatings either have constituents in the nanoscale or are made out of layers that are under 100 nm. Nanocoatings are used effectively to lessen the impact of a corrosive environment due to its various preferences, such as surface hardness, adhesive quality, long haul and, additionally, high-temperature corrosion opposition, and to improve its tribological properties, and so forth. Moreover, nanocoatings can be utilized in more slender and smoother thickness, which permits adaptability in equipment design and lower upkeep and working expenses. This review covers applications related to the management of metal corrosion, including the use of nanomaterials to produce high-performance corrosion inhibitors and corrosion-resistant coatings.

Influence of bending radius on longitudinal stresses in long operation pipelines

2020 ◽  
Vol 10 (3) ◽  
pp. 234-242
Author(s):  
Robert М. Askarov ◽  
◽  
Aydar К. Gumerov ◽  
Rinat M. Karimov ◽  
Khiramagomed Sh. Shamilov ◽  
...  
Keyword(s):  
Technical Condition ◽  
Regulatory Requirements ◽  
Bend Radius ◽  
Term Operation ◽  
Mandatory Requirement ◽  
Bending Radius ◽  
New Construction ◽  
The Impact ◽  
Long Operation

Calculations of stress-strain state of pipelines are performed in accordance with the unified regulatory requirements, which do not take into account facilities operation. Thus, the limitation of minimal allowable bend radius with the value of 1000 pipe diameters (1000D) can be considered justified in relation to a new construction project, but the problem is that it is applied to all pipelines independently of its service life. At the same time the modern smart pigging technologies allow for obtaining precise data on bend radius of operated pipelines, and the diagnostics results indicate, that mandatory requirement for minimal value of 1000D frequently contradicts the actual technical condition of researched objects. The authors performed the analysis of standard formula for calculation of longitudinal stresses, considered the impact on the calculated value of its separate constituents: values of pressure, temperature difference and bend radius. The conclusion is made about the necessity for reassessment of the current regulations for scientific justification of acceptable values of pipeline longitudinal stresses. It is established, that the primary factor, which is responsible for forming the value of longitudinal stresses of the pipelines during long-term operation is the bend radius.

A CYCLE THRESHOLD VALUE-BASED EPIDEMIC PROGNOSTICATION TO MONITOR LONG-TERM EPIDEMIOLOGIC TRENDS OF SARS-COV-2 VIRUS

2021 ◽  
pp. 24-30
Author(s):  
Aditi Munmun Sengupta ◽  
Diptendu Chatterjee ◽  
Bibhuti Saha
Keyword(s):  
Meta Analysis ◽  
Threshold Value ◽  
High Viral Load ◽  
World Health ◽  
Rt Pcr ◽  
Cycle Threshold ◽  
Ct Value ◽  
Health Organization ◽  
The Impact

The real-time reverse transcription-polymerase chain reaction (RT-PCR) is considered as the sensitive proof for detecting the viral infection of the SARS-CoV-2 virus obtained from respiratory samples. The quantitative values for the analysis are benecial for estimating the transmissibility of people who test positive for SARS-CoV-2. This can be further achieved by analyzing the samples by semiquantitative means through the interpretation of the cycle threshold (Ct) values of RT-PCR that represent the rst cycle of PCR at which a detectable signal appears during the assays. The Ct value shows a correlation between high viral load and disease infectiousness, which is observed with other respiratory viruses, including the inuenza B infection and rhinovirus infection. Hence, the present study aims to analyze the surveillance of COVID-19 to monitor longer-term epidemiologic trends and trends in deaths due to COVID-19. In order to achieve this aim, the present review was reported to the preferred reporting items for systematic reviews and meta-analysis statements (PRISMA) for analyzing the Ct value-based epidemic predictions and to monitor long-term epidemiologic trends of SARS-CoV-2 virus. Total 33 studies have been nalized for nding out the results of the study. The epidemiologic parameter and a representative of the surveillance data for reporting to the World Health Organization were fullled by analyzing the systematic review and metaanalysis of the selected study. Moreover, the evaluation of the impact of the pandemic on the health care system and society was achieved by analyzing the studies mentioned here.

Allergic Reactions in Rheumatic Fever Patients on Long-term Benzathine Penicillin G: The Role of Skin Testing for Penicillin Allergy

PEDIATRICS ◽  
1996 ◽  
Vol 97 (6) ◽  
pp. 981-983
Author(s):  
Milton Markowitz ◽  
Hung-Chi Lue
Keyword(s):  
Developing Countries ◽  
Rheumatic Fever ◽  
The United States ◽  
World Health ◽  
Penicillin G ◽  
Allergic Reactions ◽  
Benzathine Penicillin ◽  
Benzathine Penicillin G ◽  
The Impact

An injection of 1.2 million U benzathine penicillin G (BPG) every 3 or 4 weeks has proven by far to be the most effective method to prevent recurrences of acute rheumatic fever.1-3 The efficacy of this method of prophylaxis was first demonstrated more than 40 years ago, and since its introduction, it has played a major role in reducing the morbidity and mortality from rheumatic fever.4 Rheumatic fever causes 25% to 40% of all cardiovascular diseases in developing countries.5 Because of the impact of this disease on public health, the World Health Organization (WHO) has helped establish programs for prevention of recurrent attacks of rheumatic fever in many developing countries.6 WHO recommends BPG as the prophylactic drug of choice. One of the problems encountered has been the high drop-out rates among patients enrolled in these programs. Among the reasons for discontinuing prophylaxis is the fear of an allergic reaction.7 The initial study using BPG for the prevention of recurrences of rheumatic fever in children and adolescents reported only 5 (1.2%) mild allergic reactions among 410 patients receiving monthly injections.1 Since then, although rheumatic fever prevention in the United States (U.S.) has consisted almost exclusively of using BPG, there been very few documented reports of serious allergic reactions in rheumatic fever patients on long-term prophylaxis. The only fatalities reported in the American literature occurred in four adults with advanced rheumatic heart disease.8,9 The salutary experience with BPG in the U.S. contrasts sharply with the numerous anecdotal reports of fatal allergic reactions to BPG in many developing countries.

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