154 research outputs found
Air pollution at Rochester, NY: Long-term trends and multivariate analysis of upwind SO2 source impacts
No full textThere have been many changes in the air pollutant sources in the northeastern United States since 2001. To assess the effect of these changes, trend analyses of the monthly average values were performed on PM2.5 and its components including major ions, elemental carbon (EC), organic carbon (OC), and gaseous pollutant concentrations measured between 2001 (in some cases 1999) and 2015 at the NYS Department of Environmental Conservation sites in Rochester, NY. Mann-Kendall regression with Sen's slope was applied to estimate the trends and seasonality. Using piecewise regression, significant reductions in the air pollution of Rochester area were observed between 2008 and 2010 when a 260 MW coal-fired power plant was decommissioned, new heavy-duty diesel trucks had to be equipped with catalytic regenerator traps, and the economic recession that began in 2008 reduced traffic and other activities. The monthly average PM2.5 mass showed a downward trend (− 5 μg/m3; − 41%) in Rochester between 2001 and 2015. This change is largely due to reductions in particulate sulfate that showed a 65% decrease. The sulfate concentrations were compared to changes in SO2 emissions in seventeen upwind source domains, and other systematic changes by multivariate linear regression. Selectivity ratio obtained from target projection discriminated the most important source domains that are SO2 emissions from Georgia for winter, North Carolina for transition (spring and fall) and Ohio along with other influences for summer. North Carolina and Michigan were identified as the main sources for entire period. These observations suggest that any further reductions in the specified regional SO2 emissions would result in a proportional decrease in sulfate in Rochester
Palynostratigraphy of the Shemshak and Dalichai formations boundary, north of Semnan and its paleogeographic significance
No full textAbstractThe palynofloras of the Shemshak (upper part) and Dalichai (lower part) formations, Deh-Soufian, north of Semnan include 57 species of spores (34 genera), 25 species of pollen (13 genera), and 14 species of dinoflagellate cysts (8 genera). Based on the stratigraphic distribution of miospores, the Klukisporites variegatus-Striatella spp.-Contignisporites burgeri assemblage biozone (Middle Jurassic) is introduced. The co-occurrence in the palynofloras examined of Contignisporites burgeri and Striatella seebergensis allows for the Bajocian–Bathonian boundary to be located 75m below the boundary of Shemshak-Dalichai rock units. The presence in the strata below this chronostratigraphic horizon of Mendicodinium scabratum (Bajocian) supports this age assignment. The boundary of Shemshak and Dalichai (with basal sandstone) formations is discontinuous. While no significant change in the composition of miospores is discernible in palynofloras retrieved from the above rock units, the relative abundance of such terrestrial palynomorphs varies drastically. This might be attributed to side effects of the mid-Cimmerian Orogeny i.e., significant change in sedimentation rate resulting in change from the deltaic to marine depositional settings. It should be noted that 45 m below the boundary of the two rock units 24 miospore species exit whereas 11 different ones appear 20 m above that boundary. Notable correspondence of the Iranian Middle Jurassic palynofloras across the Alborz Ranges signifies to a rather significant coastal vegetation similarity of the time in the area. Whereas both Gondwanan and Eurasian miospore key species occur in the palynofloras examined those particularly endemic to the southern landmasses are missing from the palynofloras studied. Palynological evidence seemingly confirms the location of the Alborz Ranges on the northwestern margin of the Neotethys Ocean in the Middle Jurassic. The available paleontological data (ammonites and dinoflagellate cysts) apparently support this interpretation.Keywords: Palynostratigraphy, Paleogeography, Middle Jurassic, Shemshak and Dalichai formations. IntroductionJurassic strata widely distributed and exposed in the Alborz Ranges (Majidifard 2008) consist of deposits of two large sedimentary-tectonic cycles (Aghanabati 1975). Those of the first Upper Triassic–Lower Jurassic sedimentary cycle are known as the Shemshak Formation (Assereto 1966; Fürsich et al. 2009) or the so-called Shemshak Group whereas strata of the second sedimentary megacycle (Middle-Upper Jurassic) in east-central Iran are known as the Magu Group.Lithological variation, biological attributes, and depositional settings reflected by the Jurassic rocks in Iran indicate that the geologic changes were closely related to the tectonic events (Majidifard 2003). Much of the Shemshak Formation sedimentation in the Alborz Ranges took place on coastal plains in fluvial, lacustrine, or deltaic settings, paralic swamps, lakes, meandering, as well as, braided rivers, and shallow–deep shelfal environments (e.g., Seyed-Emami 2003; Seyed-Emami et al. 2008). The Upper Triassic and the lowermost Jurassic rocks are very similar, so in most cases, the two-time intervals cannot be differentiated (Majidifard 2003; Seyed-Emami 2003; Seyed-Emami et al. 2008). Due to its vast thickness in many areas (up to 4000 m), some have elevated the unit to group rank (e.g., Aghanabati 1998; Seyed-Emami 2003; Fürsich et al. 2009a). Consequently, the unit has been subdivided into various members/formations, and different lithostratigraphic schemes have been proposed (Nabavi and Seyed-Emami 1977; Nabavi 1980; Repin 1987; Aghanabati 1998; Seyed-Emami et al. 2020). It contains diverse biota such as plant fossils (e.g., Sadeghi and Hashemi 2021), and ammonites (e.g., Seyed-Emami et al. 2020). However, due to the poor preservation of palynomorphs, the Shemshak Formation has remained almost unstudied palynologically.The Magu Group, the second sedimentary megacycle consists primarily of fossiliferous marls and limestones indicating basin and platform depositional setting (Lasemi 1995). These accumulated from the end of the Mid-Cimmerian tectonic phase (Middle Jurassic) till the Late Jurassic and, in some places, continued during the Neocomian (Seyed-Emami 1975; Keshani 1988; Seyed-Emami and Alavi-Naini 1990; Majidifard 2003, 2008; Fürsich et al. 2009).The Dalichai Formation (Steiger 1966), the oldest rock unit of the Magu Group (Aghanabati 1998) comprises shale, light-grey to bluish-grey limestones with thin intercalations of marls (Majidifard 2003, 2008). It contains diverse biota such as ammonites, spores and pollen grains, dinoflagellates cysts, belemnites, bivalves, brachiopods, echinoids, sponges, bryozoans, and foraminifera (Stöcklin 1972; Alavi-Naini 1972; Sussli 1976; Nabavi and Seyed-Emami 1977; Alavi-Naini et al. 1982; Seyed-Emami et al. 1985, 1989, 1995, 1996; Wheeler and Sarjeant 1990; Schairer et al. 1991; Shahrabi 1994; Makvandi 2000; Tutunchi 2001; Ghasemi-Nejad and Khaki 2002; Shafeizad et al. 2002; Farisi Kermani 2003; Shafeizad and Seyed- Emami 2005; Alvani 2006; Shams 2007; Niknahad 2007; Ghasemi-Nejad et al. 2008, 2012; Hashemi Yazdi 2008, 2015; Majidifard 2008; Seyed-Emami et al. 2008; Sabbaghiyan 2009; Sajjadi et al. 2009; Vaziri et al. 2008, 2011; Dehbozorgi 2013; Dehbozorgi et al. 2013; Mafi et al. 2013; Navidi Izad 2013; Dietze et al. 2014; Skupien et al. 2015). Study of ammonites indicates a late Bajocian to Oxfordian age for the Dalichai Formation (Lorenz 1964, Sussli 1976; Nabavi and Seyed-Emami 1977; Seyed-Emami et al. 1985, 1995, 2013; Schairer et al. 1991; Majidifard 2003, Seyed-Emami and Schairer 2010, 2011a, b). According to paleontological and lithological evidence the Dalichai Formation was deposited in a marine environment (Lorenz 1964, Steiger 1966, Wheeler and Sarjeant 1990, Zarei 2017). Furthermore, ammonite data shows close relationships to those from epicontinental seas fringing the northern margin of the western Tethys and an intermediate position between the Subboreal and Submediterranean provinces (Seyed-Emami et al. 2013, 2018; Dietze et al. 2014; Seyed-Emami and Raoufan 2017).The aim of this study is to document the palynological content of the Shemshak and Dalichai formations boundary at Deh-Soufian, north of Semnan, to assess its stratigraphic and palaeogeographical significance and compare it to other Middle Jurassic records of Eurasia and Gondwana. Material & MethodsTwenty-one samples were collected from shale intervals at the Deh-Soufian stratigraphic section (N 35° 47' 44" and E 53° 40' 03"); nine samples from the uppermost of the Shemshak Formation and twelve samples base of the Dalichai Formation. Standard palynological procedures (e.g., Phipps and Playford 1984, Wood 1996) applied for extraction and concentration of the palynomorphs. Samples were first disaggregated into pea-sized pieces (1–2 mm in diameter) and treated with 30% HCl to eliminate carbonates. The residue was then washed to neutrality and the remaining inorganic matter dissolved in HF (ca. 40%); fluoride precipitants formed were subsequently removed using hot 30% HCl followed by washing to neutrality. The organic residue was sieved via 20 μm mesh. Heavy minerals and other remaining inorganic particles were then removed by the use of a heavy-liquid solution (ZnCl2) at appropriate specific gravity. The remaining residue was then sieved through 20 μm nylon sieve prior to mounting on permanent slides. At least three permanent strew slides per sample were prepared using Entellan as the mounting medium. Discussion of Results & ConclusionsThe palynofloras examined comprise 57 spore species (assigned to 34 genera), 25 pollen species (attributed to 13 genera), and 14 species of dinoflagellate cysts (allocated to eight genera). The vertical ranges of certain miospore species with known stratigraphic significance and/or persistence throughout the section investigated authorize the introduction of one informal local biozone as Klukisporites variegatus-Striatella spp.-Contignisporites burgeri assemblage biozone. The presence of multiple Striatella species, as well as, Contignisporites burger and Klukisporites variegatus collectively indicate a Middle Jurassic (Bajocian–Bathonian) age. The co-occurrence in the palynofloras examined of Contignisporites burgeri and Striatella seebergensis allows for the Bajocian–Bathonian boundary to be located 75 m below the boundary of Shemshak and Dalichai rock units. The presence in the strata below this chronostratigraphic horizon of Mendicodinium scabratum (Bajocian) supports this age assignment.The lithology of the Shemshak Formation includes sandstone and shale alternations, and the Dalichai Formation includes basal sandstone followed by limestone and shale alternations. The boundary between the two mentioned formations is discontinuous due to the presence of a sandstone layer at the base of the Dalichai Formation.No significant change in the diversity of miospore species is observed in the border of the mentioned rock units, but their relative abundance in this horizon is associated with a significant decrease. This might be considered a side effect of the mid-Cimmerian Orogeny, i.e., a significant change in sedimentation rate resulting difference in the sedimentation environment from the deltaic (Shemshak Formation) to the marine environment (Dalichai Formation).It should be noted that 24 miospore species disappear 45 meters below the border of the Shemshak and Dalichai formations, and 11 different miospore species appear 20 meters above this border. The comparative palynofloras found in the Iranian Middle Jurassic rocks of the Alborz Ranges recommend that there were likely comparative types of coastal plants in that area during that time. The key miospore species from both Gondwana and Eurasia are found in the examined samples, but the species that are unique to the southern landmasses (e.g. Aequitriradites norrisii, Anapiculatisporites dawsonensis, A. pristidentatus, and ….) are not present in the samples studied. The investigated palynomorphs indicate that throughout the Middle Jurassic, the Alborz Ranges were located alongside the northwestern edge of the Neotethys Ocean. The ammonites and dinoflagellate cysts apparently support this elucidation
Cyclic Test of Steel Plate Shear Wall Designed by PFI Method
No full textIn this paper, Plate Frame Interaction (PFI) developed by other researches for modeling Steel Plate Shear Wall (SPSW) is applied for designing a half-scale, single bay and one story SPSW. After designing of SPSW, one specimen is constructed accordingly. In order to determine the mechanical properties of steel, coupon test is performed; and then again theoretical relations based on PFI is re-checked. In this study, gravity loads are neglected and only seismic resistance of SPSW is considered. With cyclic lateral loading as quasi-static load, according to Acceptance Criteria for Cyclic Racking Shear Tests For Metal-Sheathed Shear Walls with Steel Framing (AC154) and obtaining its hysteretic loops, force displacement diagram of the specimen is determined. Comparison of theoretical and experimental results shows that ultimate strength of SPSW based on theoretical analysis is lower than that of experimental analysis. By the way, due to large deformation of beam during the applied loading, it is proposed that plastic moment of beam be get higher, rather than that of proposed quantity. However, through increasing of beam and column rigidity and attention to weak girder- strong column theory, it is estimated that ultimate strength, ductility and energy dissipation of steel shear wall will significantly improve.</jats:p
Coupling of soft‐modeling methods with multivariate pattern recognition technique for the identification of nitroaniline isomers
No full text
Long-Term Changes of Source Apportioned Particle Number Concentrations in a Metropolitan Area of the Northeastern United States
No full textThe northeastern United States has experienced significant emissions reductions in the last two decades leading to a decrease in PM2.5, major gaseous pollutants (SO2, CO, NOx) and ultrafine particles (UFPs) concentrations. Emissions controls were implemented for coal-fired power plants, and new heavy-duty diesel trucks were equipped with particle traps and NOx control systems, and ultralow sulfur content is mandatory for both road and non-road diesel as well as residual oil for space heating. At the same time, economic changes also influenced the trends in air pollutants. Investigating the influence of these changes on ultrafine particle sources is fundamental to determine the success of the mitigation strategies and to plan future actions. Particle size distributions have been measured in Rochester, NY since January 2002. The particle sources were investigated with positive matrix factorization (PMF) of the size distributions (11–470 nm) and measured criteria pollutants during five periods (2002–2003, 2004–2007, 2008–2010, 2011–2013, and 2014–2016) and three seasons (winter, summer, and transition). Monthly, weekly, and hourly source contributions patterns were evaluated
Experimental investigation on the behavior of corrugated steel shear wall subjected to the different angle of trapezoidal plate
No full textIranian Mathematical Society A family of large set of size nine A FAMILY OF LARGE SET OF SIZE NINE
No full textAbstract. We investigate the existence of some large sets of size nine. The large set L
Persian school 2014
No full textTo design a contemporary Persian school in which the essence of the traditional Persian Architecture is constructed, in combination with integrating new pedagogic ideas.Explore LabArchitectureArchitecture and The Built Environmen
Marriage and divorce law in Pre-Islamic Persia. Legal status of the Sassanid’ woman (224–651 AD)
No full textFormore than 400 years, the Sassanid Persia was the greatest state in Asia.
Zoroastrianism supported by Shahanshahs had an immense influence on the legal
principles of the state. The Sassanian society was Patriarchy, based on the society’s
gender construction. Because the patriarchal constructions of social practices were
legitimized by religion, the basic limitation of the women’s rights in the Sassanian
period was the obligation to have the male guardian. Below considerations regard the
problem of the civil rights of Sassanian women, based on analysis of the legal status of
women in marital unions. In 2018, in the journal Cogent Arts & Humanities 5, 1, an
article by Mahmoud Emami Namin “Legal status of women in the Sassanid’s Era
(224–651 AD)” was published. In his paper, Dr. Mahmoud Emami Namin, arguments
against two theses presented by the researchers studying the Sassanian history. The
first thesis is related to the assumption that women lacked a legal entity, and, consequently,
could not make use of her rights. The second thesis, challenged by the author
is related to the “opinions about the prevalence of incestuous marriage (next-of-kin
marriage) and loan marriage (wife lending) among the Sassanids”. The author challenges
the arguments regarding the position of the Sassanian women presented by
two distinguished orientalists Christian Bartholomae and Arthur Christensen.
Obviously, he is right. However, it is necessary to note that the picture of Persia depicted
by the above-mentioned researchers was questioned bymodern historians a few years
ago. Theses made by Professor Christian Bartholomae, presented in German University
of Heidelberg, in 1924 (the woman’s rights in the Sassanid’ Empire), related to the lack
of legal status of women in pre-Islamic period, which Dr. Mahmoud Emami Namin polemizes with, were refuted by the research conducted by the expert on Sassanid law
Professor Maria Macuch (see in References). The second problem, Dr. Mahmoud Emami
Namin focusses on, is “the authorization of incest”,which was discussed by Christensen
and Bartholomae. This part of the paper is much more interesting and presents interesting
conclusions. One must agree with Dr. Mahmoud Emami Namin in that the
“incest” was a common practice among Zoroastrians in the Sassanid’s period, andwas
never deemed “weird and offensive”. The paper lacks the analysis related to factors
contributing to the negative picture of Persia in scientific literature written in the
previous century. It seems to have predominantly resulted from cultural differences.
Orientalists studying the history of the Sassanids were from the “western culture”.
Therefore, they did not understand the mentality of the society governed by
Zoroastrian principles, which reflected their descriptions of the pre-Islamic Persia. Their
ethical assessment and interpretation of sources were determined by the system of
values, in which they had been brought up. It should be noted that the manuscript
contains extremely interesting passages in the manuscript related to the legal aspects
of different types of marriages, financial conditions or children’s rights. In the manuscript,
the author presents a slightly different division of marriages that the one
proposed by Dr. MahmoudEmami Namin. It seems that the principal assumptionmade
by the author: “Throughout this paper, the baseless writings of orientalists about the
rights of the Sassanid’s women are critically examined” may be described as preaching
to the converted
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