Wave Profile for Anti-force Waves with Maximum Possible Currents

In the theoretical investigation of the electrical breakdown of a gas, we apply a one-dimensional, steady state, constant velocity, three component fluid model and consider the electrons to be the main element in propagation of the wave. The electron gas temperature, and therefore the electron gas partial pressure, is considered to be large enough to provide the driving force. The wave is considered to have a shock front, followed by a thin dynamical transition region. Our set of electron fluid-dynamical equations consists of the equations of conservation of mass, momentum, and energy, plus the Poisson\u27s equation. The set of equations is referred to as the electron fluid dynamical equations; and a successful solution therefor must meet a set of acceptable physical conditions at the trailing edge of the wave. For breakdown waves with a significant current behind the shock front, modifications must be made to the set of electron fluid dynamical equations, as well as the shock condition on electron temperature. Considering existence of current behind the shock front, we have derived the shock condition on electron temperature, and for a set of experimentally measured wave speeds, we have been able to find maximum current values for which solutions to our set of electron velocity, electron temperature, and electron number density within the dynamical transition region of the wave

Relationship between the communication skill of nurse - patient with patient safety in the critical care units

زمینه و هدف: تمرکز روی ایمنی بیمار در بخش های مراقبت ویژه موضوعی مهم است و در این بین یکی از مهم ترین عوامل مربوط به ایمنی بیمار، مهارت های ارتباطی بین پرستار و بیمار می باشد. این مطالعه با هدف تعیین رابطه بین مهارت ارتباطی پرستار - بیمار با وضعیت ایمنی بیماران در بخش های ویژه بیمارستان های شهر ارومیه از دیدگاه پرستاران انجام شد. روش بررسی: در این مطالعه توصیفی - همبستگی، 167 پرستار شاغل در بخش های ویژه بیمارستان های آموزشی و غیر آموزشی شهر ارومیه با روش تمام سرشماری شرکت کردند. جهت جمع آوری داده ها از پرسشنامه های روا و پایا شده ی مهارت ارتباطی پرستار - بیمار و وضعیت ایمنی بیمار استفاده شد و مهارت ارتباطی پرستار - بیمار ارزیابی و ارتباط آن با وضعیت ایمنی بیماران تعیین شد. یافته ها: اکثریت پرستاران شاغل در بیمارستان های آموزشی و غیر آموزشی (به ترتیب 5/97 و 8/97 درصد) مهارت ارتباطی خود را در سطح خوب ارزیابی کردند. همچنین 6/87 درصد پرستاران بیمارستان های آموزشی و 8/84 پرستاران بیمارستان های غیر آموزشی ایمنی بیماران را در سطح خوب ارزیابی کردند. بین مهارت ارتباطی پرستاران با وضعیت ایمنی بیماران در بخش ویژه رابطه معنی دار آماری وجود داشت (001/0>P). نتیجه گیری: با توجه به نتایج این مطالعه پرستاران می توانند با بکارگیری مهارت های ارتباطی مناسب با بیماران بستری در بخش های ویژه، ایمنی آن ها را حفظ و ارتقاء بخشند

Multilevel Analysis of Effective Factor on Academic Resilience Among High School Students of Underdeveloped Regions of Mobarakeh

A this study aimed to determine the factors influencing resilience at individual, family and school level and surveyed on 250 female (n=192) and male students (n=58) of less developed regions in the Mobarekeh. Hierarchical liner regression (HLM) showed that individual (self-esteem and academic motivation) and the family-level variables (family social capital) have significant relationship with academic resilience and despite the school level variables associated with resilience in the second model, with the entrance of other variables in the final model, the relationship becomes insignificant. Finally, some suggestions provided for improving resilience in these areas

Current Range in Lightning Return Strokes

In our investigation of breakdown waves, we use a one-dimensional, steady-state, constant velocity fluid model. This investigation involves breakdown waves for which the electric field force on electrons is in the opposite direction of wave propagation. The waves are considered to be shock fronted and the electron gas partial pressure is large enough to sustain the wave propagation. Our basic set of electron fluid-dynamical equations is composed of the equations for conservation of mass, momentum and energy, coupled with Poisson’s equation. This investigation involves breakdown waves for which a large current exists behind the shock front. The current behind the shock front alters the set of electron fluid-dynamical equations as well as the boundary conditions at the shock front. For the range of reported experimental current values (Wang et al. 1999), we have been able to solve the electron fluid dynamical equations within the dynamical transition region of the wave. Wave profile for electric field and electron velocity, number density and temperature within the dynamical transition region of the wave will be presente

The Temperature of the CMB at 10 GHz

We report the results of an effort to measure the low frequency portion of the spectrum of the Cosmic Microwave Background Radiation (CMB), using a balloon-borne instrument called ARCADE (Absolute Radiometer for Cosmology, Astrophysics, and Diffuse Emission). These measurements are to search for deviations from a thermal spectrum that are expected to exist in the CMB due to various processes in the early universe. The radiometric temperature was measured at 10 and 30 GHz using a cryogenic open-aperture instrument with no emissive windows. An external blackbody calibrator provides an in situ reference. A linear model is used to compare the radiometer output to a set of thermometers on the instrument. The unmodeled residuals are less than 50 mK peak-to-peak with a weighted RMS of 6 mK. Small corrections are made for the residual emission from the flight train, atmosphere, and foreground Galactic emission. The measured radiometric temperature of the CMB is 2.721 +/- 0.010 K at 10 GHz and 2.694 +/- 0.032 K at 30 GHz.Comment: 8 pages including 5 figures. Submitted to The Astrophysical Journa

Investigating the Effect of Polythin and Polydrill on the Properties of Drilling Fluids

In this study, synthetic sulfonated polymers were used in order to enhance the rheological properties of drilling fluids. The capability of these polymers in reducing the effects of environmentally friendly, but harmful, pollutants such as cement, calcium chloride, gypsum as well as pH changes were investigated. In the present work, two sulfonated synthetic polymers, namely Polythin and Polydrill, which are considered to be environmentally friendly polymers, were used. Polydrill controls the fluid loss and is resistant to high temperatures and also pollutants. The injection of this polymer into drilling fluid slightly increases the viscosity levels. Polythin prevents the precipitation of bentonite at high temperatures and facilitates fluid pumping by reducing its rheological and static shear strength. Polythin polymer also prevents the formation of bentonite gelation (precipitation of bentonite) at higher temperatures and is stable up to 260 °C. This polymer is also capable of completing the effects of fluid loss additives and reduction of filtration in HTHP drilling fluids. Furthermore, this polymer reduces rheology, strength, and static shearing values and facilitates pumping of the drilling fluid. The combination of aforementioned polymers improves the thermal resistance of drilling muds while maintaining the rheology and reducing the amount of filtrate for HTHP drilling fluids. In these experiments, the rheological properties of the fluid including apparent viscosity (AV), plastic viscosity (PV), yielding point (YP), gelation resistance or gel strength (GEL), fluid loss (FL), and the pH of the fluid were studied before and after the addition of the pollutants. The results indicate that certain proportions of these two polymers increase the rheological properties of drilling fluids and can significantly change the weight percentages of pollutants. It is also notable that the rheological properties were normally constant. However, in some cases, smaller values of rheological parameters enhanced the efficiency in the presence of pollutants. In the case of calcium chloride, rheological parameters (AV, PV, YP, and gel strength) are almost constant, while fluid loss greatly increases

Microstructure and Phase Formation in a Rapidly Solidified Laser-Deposited Ni-Cr-B-Si-C Hardfacing Alloy

In this study, microstructural evolutions and phase selection phenomena during laser deposition of a hardfacing Ni-Cr-B-Si-C alloy at different processing conditions are experimentally investigated. The results show that even minor variations in the thermal conditions during solidification can modify the type and morphology of the phases. Higher undercoolings obtained at faster cooling rates suppressed the primary borides and encouraged floret-shape mixtures of Ni and Cr5B3 via a metastable reaction. Variations in the boride phases are discussed in terms of nucleation-and growth-controlled phase selection mechanisms. These selection processes also influenced the nature and proportion of the Ni-B-Si eutectics by changing the amount of the boron available for the final eutectic reactions. The results of this work emphasize the importance of controlling the cooling rate during deposition of these industrially important alloys using laser beam or other rapid solidification techniques. (C) The Minerals, Metals & Materials Society and ASM International 201

Fabrication of Pd NPs on pectin-modified Fe3O4 NPs: A magnetically retrievable nanocatalyst for efficient C-C and C-N cross coupling reactions and an investigation of its cardiovascular protective effects

The present report represents the synthesis of a novel Pd NPs immobilized over a natural polysaccharide (pectin) coated Fe3O4 magnetic nanocomposite material (Fe3O4@pectin/Pd) for investigating the cardiovascular protective effects. The biomolecular functionalization not only stabilizes the ferrite nanoparticles from agglomeration but also provides an environment for the biogenic reduction of Pd2+ ions. This protocol is a promising breakthrough for the synthesis of a quasi-heterogeneous catalyst, a bridge between heterogeneous and homogeneous medium. The structure, morphology and physicochemical properties of the material were characterized utilizing various analytical techniques like FT-IR FE-SEM, TEM, VSM, EDX-elemental mapping, ICP, EDX and XPS. The catalyst showed excellent reactivity in C-C and C-N cross coupling reactions via Suzuki and Buchwald-Hartwig reactions respectively. An array of different biphenyls and aryl amines were then procured by reactions of various aryl halides with phenyl boronic acid or secondary amines over the catalyst affording good to excellent yields. The catalyst was easily recoverable using an external magnet and thereafter recycled for several trials with insignificant palladium leaching or loss in catalytic performance. To investigate the cardiovascular protective activities of catalyst, the MTT assay was done on Human Aortic Endothelial Cells (HAEC), Human Coronary Artery Endothelial Cells (HCAEC), and Human Pulmonary Artery Endothelial Cells (HPAEC) cell lines. Nanocatalyst-treated cell cutlers significantly (p <= 0.01) decreased the caspase-3 activity, and DNA fragmentation. It raised the cell viability and mitochondrial membrane potential in the high concentration of Mitoxantrone-treated HAEC, HCAEC, and HPAEC cells. According to the above findings, nanocatalyst can be administrated as a cardiovascular protective drug for the treatment of cardiovascular diseases after approving in the clinical trial studies in humans. (C) 2020 Published by Elsevier B.V