Study of the Effects of Acidic Ions on Cloud Droplet Formation Using Laboratory Experiments

AbstractAtmospheric aerosols affect climate of the Earth, scatter sunlight and serve as cloud condensation nuclei (CCN). Yet the reason for many observed events of new aerosol formation is not understood. One of the ideas put forward to explain these events is that the presence of SO42- can enhance the formation of aerosols. These sulphate aerosols form partly during the oxidation of the oceanic emission Dimethyl sulfide (DMS) into the atmosphere and partly from volcanoes, plants and soils, fossil fuel combustion, and biomass burning. In this paper, laboratory experiments on warm cloud formation with different acid ion density are presented. The results show that the lifetime of cloud is reduced by increasing density of SO42-, but this changes is not significant (significance level, P=0.578), while the cloud concentration is significantly changed with the decreasing of density of SO42- (P=0.001). There is also a good significant correlation between cloud concentration with the maximum temperature change, with correlation coefficient, r=0.646 (p=0.004)

The study of layering structure of outlfow from the Persian Gulf to Gulf of Oman and it's impact on propagation of sound with acoustic sources about outflow intrusion at spring

In this study, variations of field data such as temperature, salinity and sound of speed in horizontal and across transects of the Gulf of Oman were analyzed using CTD data acquired by international project, Joint Global Ocean Flux Study (JGOFS) during the spring of 1996. Results indicate that at all sections, at depths between 120 m to 276m in Gulf of Oman to 60 °E, finestructures were found; this indicates mixing with surrounding waters by thermohaline intrusions. These thermohaline intrusions caused temperature and salinity inversion that causes inversion of sound speed profile. Thickness inversion at the stations near the Strait of Hormuz is about 156 m and at stations far from the Strait of Hormuz (near the Oman of Sea) is about 80m. By previous studies, this outflow intrusion causes the internal waves in the Gulf of Oman. These results suggest that formation of intrusion depends on the intermittent outflow through the Strait of Hormuz. In this survey, high salinity water and high temperature water masses spread into the Persian Gulf at an intermediate level, in the Gulf of Oman. In this research, the acoustic propagation characteristics (transmission loss, amplitude of signal and travel time of signal) up, below and into, of the outflow intrusion were assessed based on the output of a range-dependant acoustic model and range independent acoustic model. In general, the occurrence of this thermohaline intrusion was found to alter the propagation characteristics

Numerical calculation of prandtl number in the stratification of water column of the Hormuz Strait

Turbulence is a form of movement characterized by an irregular or agitated motion. Turbulent motions are very common in nature. Most flows in the lower atmosphere and in the upper ocean are turbulent. The Turbulence has long had a special attraction for physicists and mathematicians; it has been called “the last great unsolved problem of classical physics”. In this study, hydrophysical measured data in the southern part of the Strait of Hormuz and with time step of half an hour during the period December 1996 to March 1998, by the University of Miami, and the meteorological station in island of Gheshm are used, then turbulence was simulated by General Ocean Turbulence Model (GOTM) (the second-order turbulent closure of Cheng et al. (2002) using the k-ε equations). The results showed that, turbulent kinetic energy (TKE) in different seasons, with different penetration depths were appeared at during the year. In the cold season, the kinetic energy of the turbulent expands from surface to bottom and in the warm seasons because of existing the seasonal thermocline, depth penetration of TKE are limited, and only expands from surface to top of thermocline layer. In this study, investigation of the turbulent Prandtl number (Pr) shows that, effect turbulent viscosity Preference to the production buoyancy in the middle depth

Prasugrel results in higher decrease in high-sensitivity C-reactive protein level in patients undergoing percutaneous coronary intervention comparing to clopidogrel

Objectives: A growing body of clinical and laboratory evidence indicates that inflammation plays a crucial role in atherosclerosis. In the present study, we compared the effects of clopidogrel and prasugrel on high-sensitivity C-reactive protein (hs-CRP) in patients undergoing percutaneous coronary intervention (PCI). Methods: The present randomized, double-blind clinical trial included 120 patients who underwent PCI. Eligible patients were randomly assigned 2:1 to one of the two groups: 80 patients in the first group received clopidogrel (Plavix®; loading dose and maintenance dose of 300 and 75 mg daily, respec-tively) and 40 patients in the second group received prasugrel (Effient®; loading dose and maintenance dose of 60 and 10 mg, respectively) for 12 weeks. The hs-CRP levels between baseline and 12th week were compared.Results: Of the 120 patients, 69 patients (57.5) were male. Pretreatment hs-CRP level was statistically comparable in clopidogrel (median, 15.10 mg/dL; interquartile range IQR, 9.62-23.75 mg/dL) and prasugrel groups (median, 18 mg/dL; IQR, 14.25-22 mg/dL; P = 0.06). Patients taking clopidogrel showed a significant reduction in hs-CRP level compared with the baseline values (P < 0.001). Prasugrel administration also resulted in a significant reduc-tion in hs-CRP level (P < 0.001). A significant 73% overall reduction in the hs-CRP level was seen with prasugrel compared with 39% overall reduction in hs-CRP level with clopidogrel (P = 0.002). Conclusion: Prasugrel seems to be superior to clopidogrel in the reduction of hs-CRP in patients undergoing PCI. © the authors, publisher and licensee Libertas Academica Limited

A three dimensional numerical simulation for prediction of oil trajectory due to extraction activity in region between Khark Island and Busher Port in winter, Persian Gulf, Iran

2298-2314Present study consists three- dimensional numerical model of the prediction of the movement of oil slicks and diffusion oil particles in the water column.  Model has previously been developed <span style="font-size:9.0pt; font-family:" times="" new="" roman","serif";mso-fareast-font-family:"times="" roman";="" mso-ansi-language:en-gb;mso-fareast-language:en-us;mso-bidi-language:fa"="" lang="EN-GB">in the Assalouyeh Marine Region<span style="font-size:9.0pt; font-family:" times="" new="" roman","serif";mso-fareast-font-family:"times="" roman";="" mso-ansi-language:en-gb;mso-fareast-language:en-us;mso-bidi-language:hi"="" lang="EN-GB"> in the north coast of Persian Gulf, Iran and has been achieved good results. This model has been run for oil spill accident between Khark Island and Busher Port in winter (2005).  Model predicts concentration distribution of oil particles and current speeds and directions for 1.7, 7 and 14 hours after spill accident in the water column in 5,10 and 15 meters levels. Numerical results show that oil particles spread towards Khark Island and away from Busher Port in winter. Diffusion oil particles in the water column due to more turbulence are larger.  Spreading follow the flow fields that are in good agreement with flow field observations and valid theories and experiment of data runs.</span

A numerical model for the prediction of movement of gas condensate from spill accidents in the Assalouyeh marine region, Persian Gulf, Iran

233-242This paper presents a three-dimensional numerical model of flow and movement of gas condensate spills based on Navier-Stokes and continuity equations with Boussinesq approximation involving various surface wind forcings. The model simulates the surface movement of gas condensate slick from spill accidents in Assalouyeh marine region. For the advection term an upwind weighted, multidimensional positive definite advection transport algorithm (MPDATA) was used. This algorithm uses an explicit finite difference scheme with an antidiffusive velocity for equilibrium diffusion. It also uses a generalized-conjugate-residual (GCR) method for the solution. The model is run for gas condensate spill accidents in Assalouyeh marine region in summer and winter of 2005. Numerical results show that gas condensate particles spread torwards the shore in summer, while in winter it mostly spreads towards east. The spreadings follow the flow fields that are in good agreement with flow field observations. Diffusion of gas condensate particles in the water due to more turbulence in winter is larger, while gas condensate particles are observed on the water surface due to more stability and buoyancy force in summer