Sensitivity to hydrogen induced cracking, and corrosion performance of an API X65 pipeline steel in H2S containing environment: influence of heat treatment and its subsequent microstructural changes

In this investigation, the effect of microstructural changes and phase equilibria on corrosion behavior and hydrogen induced cracking (HIC) sensitivity of an API X65 pipeline steel was studied. For this purpose, heat treatment was performed at 850 °C, 950 °C, 1050 °C and 1150 °C to engineer the desired microstructure of this pipeline steel. Then, the microstructural evolution was performed by optical microscopy, and Field Emission Scanning Electron Microscopy (FE-SEM) equipped with Energy Dispersive X-Ray Spectroscopy (EDS). Corrosion properties were evaluated in H2S environment by open circuit potential (OCP), Potentiodynamic polarization and Electrochemical Impedance Spectroscopy (EIS). As well, HIC sensitivity of the API X65 pipeline steel was assessed by hydrogen charging of the cathode and immediately conducting the tensile test. Microscopy analyses showed that the microstructure of the steel is ferritic-pearlitic together with the islands of martensite/austenite constituents. Increasing the heat treatment temperature reduced the amount of pearlite and increased ferrite grain size. It also stabilized the ferrite content. Corrosion results indicated that no active layer was formed on the surface of this pipeline steel. Also, increasing the heat treatment temperature increased the corrosion resistance and reduced sensitivity to micro-galvanic localized corrosion. As well, results suggested that the sensitivity to HIC in the API X65 pipeline was substantially increased with increasing the amount of pearlite and reducing the amount of ferrite; i.e. at lower heat treatment temperature.publishedVersio

Smart and biomimetic 3D and 4D printed composite hydrogels: opportunities for different biomedical applications

In recent years, smart/stimuli-responsive hydrogels have drawn tremendous attention for their varied applications, mainly in the biomedical field. These hydrogels are derived from different natural and synthetic polymers but are also composite with various organic and nano-organic fillers. The basic functions of smart hydrogels rely on their ability to change behavior; functions include mechanical, swelling, shaping, hydrophilicity, and bioactivity in response to external stimuli such as temperature, pH, magnetic field, electromagnetic radiation, and biological molecules. Depending on the final applications, smart hydrogels can be processed in different geometries and modalities to meet the complicated situations in biological media, namely, injectable hydrogels (following the sol-gel transition), colloidal nano and microgels, and three dimensional (3D) printed gel constructs. In recent decades smart hydrogels have opened a new horizon for scientists to fabricate biomimetic customized biomaterials for tissue engineering, cancer therapy, wound dressing, soft robotic actuators, and controlled release of bioactive substances/drugs. Remarkably, 4D bioprinting, a newly emerged technology/concept, aims to rationally design 3D patterned biological matrices from synthesized hydrogel-based inks with the ability to change structure under stimuli. This technology has enlarged the applicability of engineered smart hydrogels and hydrogel composites in biomedical fields. This paper aims to review stimuli-responsive hydrogels according to the kinds of external changes and t recent applications in biomedical and 4D bioprinting

A Pathology of Economic Support with Focus On Financial Assistance for Social Workers in Medical Centers

One of the most important responsibilities of social workers is economic support of the needy patients based on professional evaluation and diagnosis. The present research is a qualitative contractual content analysis. Data was collected from 18 social workers of the headquarters, universities of medical sciences, and medical centers, following focused group discussion (FGD) method with multiple-question design. The findings obtained from analyzing the codes, subcategories, and themes/category were grouped as poor intra-organizational cooperation and collaboration and irresponsible inter-organizational challenges influential on the discount topic. The inter-organizational dimension involved topics such as the weakness of hospital HIS system, interference of others in recording the discounts, poor instructions, occupation of social work posts by graduates of other majors, poor documentation, lack of personnel and facilities, lack balance between the authorities and responsibilities, and the unfamiliarity of health workers with the nature of social work. The inter-organizational dimension included the poor performance of other supporting organizations, growing social paths and undocumented immigrants, insurance role, lack of attention to some of the vulnerable groups, imposed expenses, growing visits to public hospitals, and the culture of using public resources. According to the findings of the study, different factors influence the amount and type of the economic support that the social workers provide for the needy patients and this fact imposes a great expense into the healthcare system of the country. On the other hand, it has deprofessionalized the social work profession and created a negative and low level perception towards it in the society

Improving the Antioxidant Activities of Sweet Basil (Ocimum basilicum L.) under the Influence of Different Species of Mycorrhiza under Water Stress

Introduction  Medicinal plants have long had a special role in the traditional ‎agricultural system of Iran and the use of these plants as medicine to prevent and treat diseases has been considered by ‎traditional medicine experts since ancient times. Medicinal plants with rich sources of secondary metabolites provide the ‎basic active ingredients of many medicines. Although the biosynthesis of secondary metabolites is genetically controlled, ‎but their construction is strongly influenced by environmental factors. One of the important climatic factors that affect the ‎distribution of plants around the world and can cause morphological, physiological and biochemical changes in the plant is ‎the lack of available water. Basil seems to show little resistance to water stress. For this reason, there is a need for protective mechanisms for the ‎basil plant against stress due to water shortage. Plants are able to reduce or eliminate the effects of water shortage ‎stress by coexisting with a number of soil microorganisms. Inoculation of the plants with Arbuscular mycorrhizal fungi (AMF) has been exploited as an applicable strategy for reducing detrimental effects of water deficit stress. Present study was performed to evaluate the effects of three AMF on some physiological responses of Ocimum basilicum under water deficit stress.   Materials and Methods  The pot experiments were conducted as factorial based on completely randomized design blocks with three replications. The experimental factors were three AMF namely Glomus etunicatum, Glomus mosseae and Glomus intraradices and various soil moisture including severe stress, moderate stress, mild stress. Water stress was applied from the beginning to the end of flowering stage. After flowering stage, plants ‎were harvested and traits such as total phenols and flavonoids, antioxidant ‎capacity (DPPH), malondialdehyde (MDA), catalase and peroxidase enzymes were measured. To analyze the data, first the test of data normality and uniformity of variance within the treatment was performed and confirmed. The mean of treatments was compared by Duncan test at the level of 5% probability. SAS software (Ver. 9.3) was used to analyze the data and Excel software was used to draw the graphs.   Results and Discussion  The results of analysis of variance of the effect of mycorrhiza fungus and soil moisture on the studied parameters show that the effect of different levels of soil moisture on all traits was significant. The results of analysis of variance also showed that the effect of mycorrhiza on phenol and total flavonoids, antioxidant activity, catalase and peroxidase and malondialdehyde was significant at the level of one percent probability. According to the results of analysis of variance, the interaction effect of mycorrhiza on soil moisture on antioxidant activity was significant at 5% probability level and on total phenols and flavonoids, malondialdehyde, catalase and peroxidase at 1% probability level. Results showed that AMFs improve activity of catalase and peroxidase, antioxidant capacity and total phenols which led to decrease malondialdehyde content. Antioxidants as physiologically active compounds play an important role in plant resistance to stress. Increased oxygen species due to dehydration stress are a warning sign for plants and increase the activity of antioxidant enzymes. The plant's defense system increases the production of antioxidant enzymes to neutralize toxic oxygen forms, and fungi improve the intensity of this increase, which may be due to the chemical structure of the metal isoenzymes copper, zinc, and manganese. Factors sent to make antioxidant enzymes also contain the elements zinc and calcium. Mycorrhizal fungi increase the absorption of nutrients by sending more hormonal factors and increasing the activity of enzymes, all of which can be effective in increasing the activity of antioxidant enzymes.   Conclusion  When plants are exposed to dehydration stress, reactive oxygen species in them increase. The expression of antioxidant genes and the activity of antioxidants to eliminate reactive oxygen species are increased and the antioxidant defense system is improved and the tolerance to dehydration stress in the plant is increased. Scientists believe that peroxidase is involved in metabolic processes such as hormone catabolism, defense against pathogens, phenol oxidation, binding to cell structural proteins and cell wall polysaccharides. Present study revealed that application of AMFs can be good strategy for reducing harmful effects of water deficit stress in plants. Research has also shown that impregnating seeds with mycorrhiza increases antioxidants and reduces the amount of reactive oxygen species, a characteristic of resistance induction that occurs by this antagonist.   ‎   

Spatial planning for water sustainability projects under climate uncertainty: balancing human and environmental water needs

Societies worldwide make large investments in the sustainability of integrated human-freshwater systems, but uncertainty about water supplies under climate change poses a major challenge. Investments in infrastructure, water regulation, or payments for ecosystem services may boost water availability, but may also yield poor returns on investment if directed to locations where water supply unexpectedly fluctuates due to shifting climate. How should investments in water sustainability be allocated across space and among different types of projects? Given the high costs of investments in water sustainability, decision-makers are typically risk-intolerant, and considerable uncertainty about future climate conditions can lead to decision paralysis. Here, we use mathematical optimization models to find Pareto-optimal satisfaction of human and environmental water needs across a large drought-prone river basin for a range of downscaled climate projections. We show how water scarcity and future uncertainty vary independently by location, and that joint consideration of both factors can provide guidance on how to allocate water sustainability investments. Locations with high water scarcity and low uncertainty are good candidates for high-cost, high-reward investments; locations with high scarcity but also high uncertainty may benefit most from low regret investments that minimize the potential for stranded assets if water supply increases. Given uncertainty in climate projections in many regions worldwide, our analysis illustrates how explicit consideration of uncertainty may help to identify the most effective strategies for investments in the long-term sustainability of integrated human-freshwater systems.The project described in this publication was supported by the Science Applications division of the Southwest Region of the US Fish and Wildlife Service, and by Grant No. G17AP00120, Balancing Water Usage and Ecosystem Outcomes Under Drought and Climate Change: Enhancing an Optimization Model for the Red River, from the United States Geological Survey. Open Access fees paid for in whole or in part by the University of Oklahoma Libraries.Ye

Studying native fishes in Hamadan province

Studying native fishes of Hamadan province have been done in 159 stations from 51 important water resources (wetland, reservoir, spring, river and qanat) using with electric tool, cast-net, seine and gill-net gears from July 2010 to Oct. 2011 and the main aims were species identifying and determining their distribution and abundance in the studied area. In the study, 33411 fish specimens are caught in 257 times of sampling and selected randomly about 8500 individual and laboratory works showed the fish belong to 37 species from 7 families. Cyprinidae with 25, Nemacheilidae with 6 and Sisoridae with 2 species had the most diversity and Cobitidae, Poeciliidae, Salmonidae and Mastacembelidae had only a representative. 31 fish species were native or endemic and 6 species were alien. Fish species existed in all rivers of Ghezelozan and Sirvan sub-basins but there were not any fish in 10 rivers of Ghara-Chai sub-basin and in 6 rivers of Gamasiab sub-basin, too. Also, it was observe 1-3 fish species in 15 rivers, 4-6 fish species in 10 rivers, 7-10 fish species in 5 rivers and more than 10 fish species in 4 main water resources and Gamasiab sub-basin with 32 fish species was the most diversified and Ghezelozan sub-basin with 2 fish species was the least diversified. There were any species to 4 (mostly 1 or 2) fish species in studied qanats in Ghara-Chai and Gamasiab rivers sub-basins. 23 fish species existed in a subbasin, 12 species in 2 sub-basin, Capoeta capoeta in 3 sub-basin and Squalius cephalus in all sub-basins of studied area. Alburnoides nicolausi,Capoeta aculeata and Alburnus mossulensis have had the most frequency. Studying fish abundance showed Oxynoemacheilus argyrogramma with 17.8%, Garra rufa with 12.3%, A. mossulensis with 12.1% and C. aculeata with 10.2 % of total number of caught fish specimens are dominant. S. cephalus, Capoeta damascina, C. aculeata, C. trutta, Chondrostoma regium and A. mossulensis have had sport fishing value but Acanthobrama marmid, Oxynoemacheilus kiabii, Oxynoemacheilus kermanshahensis, Turcinoemacheilus kosswigi, Alburnus caeruleus and Mastacembelus mastacembelus have biodiversity value for being endemic or having limited habitats in Iran

Environmental design solutions for existing concrete flat roofs in low-cost housing to improve passive cooling in western Mexico

The development of real estate in Mexico has largely ruled out the comfort of users that focused on economic matters and made it difficult to make substantial progress in adopting measures to improve indoor environmental quality. Current research projects in Mexico found that roof construction in low-cost housing struggles to meet the requirements of the indoor climate. Passive cooling strategies are techniques to control heat gain and heat dissipation in buildings to maximise the comfort and health of building users while minimising energy use. Passive cooling systems recognize climate conditions and utilise renewable sources of energy such as the sun and wind to provide cooling and ventilation. Therefore, this study aims to develop a green and sustainable solution for existing concrete flat roofs with no major interventions and investments to save energy. The design of a passive device was tested to assess its effectiveness to protect flat roofs from shortwave radiation and to allow for heat dissipation in Mexican buildings. The study used a quantitative approach based on experiments and simulation tests to evaluate design efficiency. The results showed that a perforated device with an opening percentage of 88% and a cavity of 0.05m between the roof and the device provided effective protection. Also, the device with blinds of 45° showed lower operative temperatures within a range of mean values between 0.8°C and 0.9°C compared to a roof with a full shade cover in the hot and humid season. However, the perforated device with blinds of 90° in black colour delivered the best performance compared to other models and recorded a mean value of 1.13°C in the hot sub-humid season. The results revealed the efficiency of the proposed device that can be observed within different geometric configurations, surface properties as well as the use of the nocturnal radiative cooling potential in blocking solar radiation in Mexican buildings

Data reduction and analysis of the multiband optical images of the blazar Mrk180

 Nearly simultaneous multiband monitoring of blazars is very limited and most studies reported in literature are conflicting, too. Although optical variability on intra-night timescales is now a well established phenomenon for blazars, its relationship to long-term variability remains unclear. Possible clues could come from monitoring the optical spectrum for correlation with brightness. The presence or absence of bluer color in blazar color index, when its luminosity is increased on intra-night and inter-night timescales, can provide interesting clues to the origin of blazar variability from hourly to much longer timescales. Luminosity of blazars varies at all wavelengths over a variety of timescales. Various models have been proposed to explain blazar variability. However, the mechanism responsible for variability is not conclusively understood. One factor which can discriminate the various variability models is that of color (spectral index) variations of blazars. This factor may help to better understand the mechanism of blazar variability. Therefore, it was initially proposed, by the second author of this paper to the OHP observatory, to carry out quasi-simultaneous multiband monitoring of one of the brightest blazer, Mrk180. Fortunately, it was accepted by the scientific team of the observatory and the 1.20m telescope time was allocated to the project from 23 to 28 April 2009. Because of the weather conditions, we could only monitor this blazar for three nights. Raw data processing and data reduction were performed using the standard system of Europe Southerner Observatory, ESO-MIDAS. We considered two reference stars and measured the magnitudes of the reference stars and the blazar Mrk 180 and then plotted the light curves and the color index diagrams. The light curves showed the optical variations of the blazar. The maximum amplitude value of its variations was 0.185 mag for the V filter. Investigating the blazar color index shows its variations on intra-night and inter-night timescales