scholarly journals Effects of the Karkheh Dam construction on haze generation due to geomorphological changes (in the Khuzestan Province, Southwest of Iran)

2021 ◽  
Author(s):  
Arash Adib
Keyword(s):  
Cross Sections ◽  
Dust Storms ◽  
Dam Construction ◽  
Khuzestan Province ◽  
Longitudinal Slope ◽  
Geomorphological Changes ◽  
The Stability ◽  
Southwest Of Iran ◽  
Hydrometric Station ◽  
The Karkheh River

Abstract An important factor for occurrence of dust storms is the construction of the Karkheh Dam in the Khuzestan province of Iran. It has reduced the annual mean of flow discharge in the Karkheh River from 120 to 50 m3/s and dried lands around river. The area of dried lands is 90.17 km2 around river and 333.45 km2 in the Hawr-al-Azim wetland. The Rosgen method, Fluvial-12 software, Shulits equation showed instability of the plan, cross sections of river and longitudinal slope of river, respectively, around Pay-e-pol hydrometric station (the upstream of river). After dam construction, extreme erosion occurred in this part of river. The type of sediment is clay and silt with D50 = 8 μm. The eroded sediment settles in downstream of river (around Hamidiyeh hydrometric station) and the Hawr-al-Azim wetland. The wind can easily lift these particles especially from May to July. Because of size of these particles, the haze concentration increased from 25% to 45% in dust storms. After construction dam, the dust storm days increased to 90 days in 2008. By increasing the stability of the river, the dust storms reduced from 2011. The annual volume of generated haze by geomorphological characteristic changes is almost 3107 m3.

An Analysis of Dissociation of Molecules in a High Resolution Electron Microscope

1973 ◽  
Vol 31 ◽  
pp. 486-487
Author(s):  
Mihir Parikh
Keyword(s):  
Electron Microscope ◽  
High Resolution ◽  
Cross Sections ◽  
Resolving Power ◽  
Peak Intensity ◽  
Molecular Film ◽  
Resolution Electron ◽  
Dissociation Cross Section ◽  
High Resolution Electron Microscope ◽  
The Stability

It is well known that the resolution of bio-molecules in a high resolution electron microscope depends not just on the physical resolving power of the instrument, but also on the stability of these molecules under the electron beam. Experimentally, the damage to the bio-molecules is commo ly monitored by the decrease in the intensity of the diffraction pattern, or more quantitatively by the decrease in the peaks of an energy loss spectrum. In the latter case the exposure, EC, to decrease the peak intensity from IO to I’O can be related to the molecular dissociation cross-section, σD, by EC = ℓn(IO /I’O) /ℓD. Qu ntitative data on damage cross-sections are just being reported, However, the microscopist needs to know the explicit dependence of damage on: (1) the molecular properties, (2) the density and characteristics of the molecular film and that of the support film, if any, (3) the temperature of the molecular film and (4) certain characteristics of the electron microscope used

scholarly journals Global predictions for astrophysics applications

2020 ◽  
Vol 13 ◽  
pp. 18
Author(s):  
P. Demetriou
Keyword(s):  
Nuclear Reaction ◽  
Cross Sections ◽  
Nuclear Reactions ◽  
Nuclear Astrophysics ◽  
Reaction Network ◽  
Reaction Rates ◽  
Reaction Cross ◽  
Hartree Fock ◽  
Microscopic Models ◽  
The Stability

Nuclear reaction rates play a crucial role in nuclear astrophysics. In the last decades there has been an enormous effort to measure reaction cross sections and extensive experimental databases have been compiled as a result. In spite of these efforts, most nuclear reaction network calculations still have to rely on theoretical predic- tions of experimentally unknown rates. In particular, in astrophysics applications such as the s-, r- and p-process nucleosynthesis involving a large number of nuclei and nuclear reactions (thousands). Moreover, most of the ingredients of the cal- culations of reaction rates have to be extrapolated to energy and/or mass regions that cannot be explored experimentally. For this reason it is important to develop global microscopic or semi-microscopic models of nuclear properties that give an accurate description of existing data and are reliable for predictions far away from the stability line. The need for more microscopic input parameters has led to new devel- opments within the Hartree-Fock-Bogoliubov method, some of which are presented in this paper.

scholarly journals Investigation of Hydrochemical Parameters of Water Resources in Kamarderaz Anticline Plunge in the Southwest of IRAN

2021 ◽  
Author(s):  
Seyed Yahya Mirzaee Aranki ◽  
Sorour Mazrae asl ◽  
Hosein Karimi Vardanjani
Keyword(s):  
Water Resources ◽  
Sulfate Reduction ◽  
Isotope Analysis ◽  
Hydrochemical Parameters ◽  
Khuzestan Province ◽  
Water Supply Management ◽  
Hydrochemical Studies ◽  
Southwest Of Iran ◽  
Karstic Water

Abstract Changes in the quality of karstic water resources affected by the proximity to sources of salinity such as evaporate formations and oil brine pose major challenges to such water resources, especially in Khuzestan province, Iran. The karstic water resources of the Kamarderaz anticline plunge in Izeh city in Khuzestan province have hampered water supply management in the region. To determine water quality and the causes of water salinity in the study area, the hydrochemical parameters of the existing water resources were accordingly evaluated. To conduct hydrochemical studies, 21 samples were collected from different water sources of Kamarderaz anticline plunge in 2017–2018. To analyze the garnered data, Piper and Durov diagrams, composite graphs, ion exchange graphs, ion correlation diagrams, salinity source diagrams and ion ratios were used. The results showed that SO42−, Cl−, and Ca2+ in the water resources of the study area were likely due to several sources including carbonate minerals, gypsum dissolution, anhydrite, halite as well as oil brine. Besides, Br/Cl, I/Cl ion ratios as well as Br-Cl and SO4-Cl diagrams revealed the mixing of karstic freshwater with oil brine in the region. The result of TOC analysis also showed that hydrocarbon materials were present in the well of Atabaki (WT). Moreover, elemental sulfur and sulfur isotope analysis showed that the process of thermochemical sulfate reduction or bacterial sulfate reduction in the presence of hydrocarbons produced H2S gas, and eventually penetrated the WT and WH1.

scholarly journals Probable evidence of a Middle Palaeolithic site in the northern parts of the Susiana Plain, Khuzestan, Iran

2019 ◽  
Vol 46 ◽  
pp. 424-433
Author(s):  
Saeid Bahramiyan
Keyword(s):  
Raw Materials ◽  
Middle Palaeolithic ◽  
Limited Information ◽  
Zagros Mountains ◽  
Significant Progress ◽  
Khuzestan Province ◽  
Different Types ◽  
Northern Regions ◽  
Considerable Body ◽  
The Karkheh River

There is a considerable body of studies regarding the activities of the Pleistocene human population in the Zagros and Alborz regions of Iran, as well as significant progress in the Palaeolithic studies in other regions, such as the foothills, plains and deserts’ margins. However, some of these peripheral regions and foothills are still neglected, and the information about the Palaeolithic period in these areas is limited. Khuzestan province, especially its northern regions, is one of these unstudied regions, yet the limited information about this region seems very interesting. Khervali, located on the western foothills of the Zagros Mountains and on the northern heights of Susa, nearby the western bank of the Karkheh River, is one of the few Palaeolithic sites identified in recent years. The site was identified in 2012 and was systemically surveyed. Due to the extension of the site and the distribution of the artefacts, sampling all the site was not feasible, therefore, four sections of the site were chosen for taking the samples and a total of 330 stone artefacts were collected. The results of the techno-typology analyses, as well as the frequency of the flakes, the Levallois samples and different types of scrapers, revealed that the artefacts date to the middle Palaeolithic period, with considerable access to the local raw materials.

Prevalence of the frailty and related factors in Iranian elderly, Khuzestan Province, southwest of Iran

2021 ◽  
pp. 1-9
Author(s):  
Ahmad Delbari ◽  
Nasibeh Zanjari ◽  
Yadollah Abolfathi Momtaz ◽  
Saeid Saeidi Mehr
Keyword(s):  
Related Factors ◽  
Khuzestan Province ◽  
Southwest Of Iran

Stability of Earth Masses and Slopes

2015 ◽  
pp. 528-588
Keyword(s):  
Cross Sections ◽  
Limit Equilibrium ◽  
Circle Method ◽  
Earth Dam ◽  
Stability Of Slopes ◽  
Solution Of Equations ◽  
Analysis Of Stability ◽  
The Stability ◽  
Cut Slopes ◽  
Type Of Failure

The design of open-cut slopes and embankments, foundations, levees, and earth-dam cross-sections is based primarily on stability considerations. There are many causes and types of earth instability. There are also many ways of analyzing the stability of slopes. The chapter considers the limit equilibrium approach, which aims essentially to determine a factor of safety, F, that would ensure a slope does not fail. The chapter considers the analysis of stability of infinite slopes based on translational type of failure and the analysis of finite slopes using the Swedish Method, Method of Slices, Bishop Simplified Method, Friction Circle Method, and the Translational Method. The solution of equations developed for the analysis of stability of slopes can be tedious and time consuming. A way of reducing the amount of calculation required in slope stability studies is by use of charts based on geometric similarity. The chapter discusses how Taylor (1948) and Janbu (1964) charts are used in stability analysis of slopes. Finally, the chapter discusses ways to reduce the risk of instability in slopes.

scholarly journals Detection ofToxoplasma gondiiby PCR and Mouse Bioassay in Rodents of Ahvaz District, Southwestern Iran

2014 ◽  
Vol 2014 ◽  
pp. 1-5 ◽  
Author(s):  
J. Saki ◽  
S. Khademvatan
Keyword(s):  
Rattus Norvegicus ◽  
Chronic Infection ◽  
Rattus Rattus ◽  
Mouse Bioassay ◽  
Intermediate Hosts ◽  
Khuzestan Province ◽  
Zoonotic Parasite ◽  
Southwestern Iran ◽  
Southwest Of Iran ◽  
Southwest Iran

Toxoplasma gondiiis obligate coccidian zoonotic parasite. Felidae family is definitive and wide ranges of warm-blooded vertebrates are intermediate hosts for the parasite. Rodents are measured as an important source ofT. gondiiinfection for the definitive host. Thus, this study aimed to investigateToxoplasminfection in rodents of Ahvaz district, southwest of Iran. A total of 100 rodents (73Rattus norvegicus, 21Rattus rattus, and 6Mus musculus) were collected and studied by GRA6PCR and mouse bioassay. The finding indicated that 6 out of 100 (6%) and 2 out of 100 (2%) samples were positive by PCR and mouse bioassay, respectively. The results show notable chronic infection in the rodent and potential transmission of the infection among animal and men in the region. Accordingly, this study recommended investigating of theT. gondiiinfection in definitive and other intermediate hosts in other points of Khuzestan province, Southwest, Iran.

scholarly journals Prevalence of subclinical coccidiosis in river buffalo calves of southwest of Iran

2013 ◽  
Vol 58 (4) ◽  
Author(s):  
Somayeh Bahrami ◽  
Ali Alborzi
Keyword(s):  
Health Condition ◽  
Multiple Infections ◽  
River Buffalo ◽  
Negative Effects ◽  
Buffalo Calves ◽  
Khuzestan Province ◽  
Significant Difference ◽  
Eimeria Spp ◽  
Southwest Of Iran ◽  
Abundance And Distribution

AbstractDespite the importance of buffalo farming in Iran, little is known in this country about the abundance and distribution of Eimeria spp. in the animal species. The present study was designed to investigate the prevalence and species characterization of Eimeria oocysts in river buffalo calves of Khuzestan province, southwest of Iran. Of the total 108 fecal samples examined for Eimeria, 108 (100%) were found infected with 11 species of the parasite. Among the identified species of Eimeria, E. bovis was found to be the predominant etiological agent (76.85%), followed in order by E. canadensis (62.96%), E. zuernii (47.2%), E. ellipsoidalis (26.85%), E. subspherica (25.92%), E. brasiliensis (19.4%), E. auburnensis (18.51%), E. alabamensis (14.81%), E. pellita (11.1%), E. illinoisensis (5.5%) and E. bukidnonensis (2.7%). In most calves multiple infections with three species were present. While, 20.7% of calves showed heavy infection, 50.4 and 24.8% of calves showed weak and moderate infection, respectively. There was no significant difference in the OPG values between the calves of different localities. There was also no significant difference between the prevalence rate of infection in males and females. A total of 16.6% of all faecal samples were found to be diarrheic. A highly significant relationship could be identified between the occurrence of diarrhea and the level of E. bovis and E. zuernii oocysts excretion. Considering the pervasive occurrence and negative effects of the infection on the health condition and the growth performance of buffalo calves, infections should receive increased attention by both farmers and veterinarians.

Analysis of Antimony-Tin-Based Skutterudites

1998 ◽  
Vol 545 ◽  
Author(s):  
S. B. Schujman ◽  
G. A. Slack ◽  
H. C. Nguyen ◽  
G. S. Nolas ◽  
R. A. Young ◽  
...  
Keyword(s):  
Cross Sections ◽  
Mixed Valence ◽  
Partial Replacement ◽  
X Ray Diffraction ◽  
Extra Charge ◽  
Semiconducting Properties ◽  
Wide Range ◽  
Diffraction Patterns ◽  
The Stability ◽  
Unit Cell Constant

AbstractSince the proposal of skutterudites as possible Phonon-Glass, Electron-Crystal materials, a lot of work has been done trying to fill the structural voids with foreign “rattling” atoms. In order to keep the electronic count per unit cell constant (and thus, the semiconducting properties of most of the compounds under study) partial replacement of either the cation or the anion in the original formula by an appropriate neighbor in the periodic table is an option. In the case of antimonides, replacing part of the Sb with Ge or Sn in order to compensate the extra charge introduced by void fillers has proved useful for compounds based on rare-earth filled IrSb3. In the case of RhSb3, we found that large quantities of Sn can be incorporated into the skutterudite structure of RhSb3 without either filling the voids or producing charge carriers.We have analyzed the stability of several cross-sections of the Rh-Sb-Sn ternary system and have found a wide range of compositions with the basic skutterudite structure as we vary the Sn content. In all the cases, the tin goes substitutionally into the antimony sites. The voids remain empty. Density measurements suggest the existence of metal vacancies, confirmed by Rietveld refinement of the powder X-ray diffraction patterns. The possibility of Sn-induced mixed-valence of Rh on the anion sites is being investigated.

Uncertainty Improvement in a Simulation of Channel Evolution

2012 ◽  
Vol 212-213 ◽  
pp. 341-344
Author(s):  
Kwang Ik Son ◽  
Taik Jean Hwang ◽  
Man Ha Hwang ◽  
Young Ho Yoon
Keyword(s):  
Nakdong River ◽  
Channel Evolution ◽  
Alluvial Channel ◽  
Longitudinal Slope ◽  
Bed Materials ◽  
Channel Degradation ◽  
The Nakdong River ◽  
The Stability ◽  
Natural Channel

The Four Major Rivers Restoration Project (4MRRP), one of the largest river rehabilitation projects in Korea, has being carried out during the last three years. 0.57 billion m3 of sediment was dredged to widen and deepen the channel along four major rivers, the Han, Nakdong, Geum, and Youngsan rivers. As a result of reshaping the natural channel to a trapezoidal channel, and the construction of 16 weirs, the change of longitudinal slope of the river was inevitable. The distribution of bed materials was also changed, due to dredging. Therefore, the rivers were totally disturbed, and the stability of the rivers could not be assured. In particular, the Nakdong river, the second largest river in Korea, has the characteristics of an alluvial channel. Degradation of the main channel bed caused bank erosion, and head-cut phenomena in many tributaries. Deformations of the main channels could be observed all along the river. Long-term simulation of the channel evolution and prediction of the stability of the Nakdong river have to be examined, to cope with the instability of the river, which could lead to unexpected river disasters. This study deals with the methodology of uncertainty improvement, in analysis of the simulation and confirmation with field survey data. Methodology of uncertainty improvement in description of weir, whose discharge coefficient is unknown, in a river was suggested.

Sign in / Sign up

Export Citation Format

Share Document