Drying Shrinkage Strain Development of Agro-Waste Oil Palm Shell Lightweight Aggregate Concrete by Using the Experimental Result, ACI and Eurocode Prediction Models

Oil palm shell (OPS) is a waste from the agricultural sector in tropical regions which could be used as aggregate in lightweight concrete mixtures. Different types of lightweight concrete with satisfactory mechanical properties were produced by using OPS. However, at early and later ages, oil palm shell lightweight aggregate concrete has higher rate of drying shrinkage compare to the normal-weight concrete. The aim of the present study is to compare the development of drying shrinkage strain based on the prediction models and experimental results. In this regard, two concrete mixes using a different level of OPS as replacement of crushed granite were produced. Two prediction models, ACI-209R and Eurocode (EC2), were applied to estimate drying shrinkage strain. In order to obtain accurate prediction for drying shrinkage strain, all effective factors for the models were applied. From the test results for drying shrinkage strain, it could be reported that both ACI and EC2 models presented close results to the experimental curves for conventional concrete (C1 mix). While, due to the high substitution level of OPS (up to 100% of aggregates) in conventional concrete, sharp increase in the drying shrinkage was observed in C2 mix. Therefore, no any suitable prediction model was found to predict close results for such concretes at early and long-term ages. Furthermor

Biostratigraphy of early Oligocene-early Miocene benthic foraminifera in Lorestan Zone, south-west Iran

925-935This study is about the microbiostratigraphy of the Asmari Formation in the Lorestan Zone, south-west Iran. Six biostratigraphical zones were defined after summarizing the available stratigraphical data and occurrence of the Early Oligocene-Early Miocene benthic foraminifera. The zones are: Nummulites intermedius, N. vascus Assemblage Zone (Ruplian, for the Laneh and Chenareh sections); Lepidocyclina-Operculina-Ditrupa Assemblage Zone (Chattian, for the Laneh section); Archaias asmaricus, Archaias hensoni- Miogypsinoides complanatus Assemblage Zone (Chattian, for Laneh and Chenareh sections); Elphidium sp.14–Miogypsina sp. Assemblage Zone (Aquitanian, for the Laneh, Chenareh and Sar Tang sections); and biozone Borelis melo curdica–Borelis melo melo Assemblage Zone (Burdigalian, for Chenareh, Sarkan and Sar Tang sections). The lower part of Asmari formation in the Sarkan section (from base to 38 m) has no index fossils, so we called it the Indeterminate Zone. The zones were successfully correlated with the biostratigraphical sachems in the Zagros Basin

Introducing of gastropoda and pelecypoda of Zayandehrud River

Zayandehrud is located in central of Iran. It is important habitats for living organisms and has a main role in diversity of flora and fauna too. Eight stations from Zayandehrud bridge up to Khajoh bridge were selected to determine Mulloscian assemblage. Malcological studies led to identification of 1 pelecypoda species (Corbicula fluminalis) and 4 Gastropoda species (Lymnae gaderosina, V. valvata piscnalis, Physa acuta and Physa sp.). All of Gasteropoda species belong to Hycanian province and only Pelecypoda belongs to North Africa and Western Asia fauna

Vent-proximal sub-seafloor replacement clastic-carbonate hosted SEDEX-type mineralization in the Mehdiabad world-class Zn-Pb-Ba-(Cu-Ag) deposit, southern Yazd Basin, Iran

© 2019. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/The Mehdiabad Zn-Pb-Ba (Cu-Ag) deposit in the southern Yazd Basin, central Iran, is the largest sediment-hosted Zn-Pb deposit in Iran. This deposit is hosted by organic carbon matter-rich shale, fine-grained black siltstone, and dolomite interlayered with sandstone of the Taft Formation. Sedimentological and geochemical studies of the Taft Formation have shown that these organic carbon matter-rich shales formed during a period of basin deepening and under anoxic conditions. Based on the orebody structure, mineralogy, and ore fabrics, we recognize five different ore facies types in the Mehdiabad deposit: (1) a stockwork/feeder zone, consisting of a discordant sulfide mineralization, forming a stockwork of sulfide-bearing dolomite veins, cutting the sedimentary rocks of the footwall; (2) massive-replacement ore, including pervasive replacement carbonate by pyrite, chalcopyrite, galena, and sphalerite with minor barite; (3) a bedded ore, with laminated to disseminated pyrite, sphalerite, and galena; (4) barite ore, which contains accessory sulfide minerals and rare calcite at the top of the deposit, and (5) a distal facies, with minor disseminated and laminated pyrite, banded cherts, and disseminated barite. Two stages of base metal sulfide replacement have separate origins. Fine-grained sulfide bands (stage I), intricately interlayered with organic carbon-rich beds and thin turbidite beds, exhibit lamina and bedding textures, supporting a syn-sedimentary (onto the sea floor) origin. Coarse-grained base metal sulfides (stage II), occurring within breccias and veins to veinlets are considered to have formed by replacement during post sedimentation sub-seafloor fluid flow. d34S values of pyrite, sphalerite chalcopyrite and galena range from -22 to +4.6.8‰. The highest d34S values correspond to the feeder zone (+4.6 and -10.5‰), whereas massive-replacement (+3.7 to -13.7‰) and bedded (-22 to -17‰) ore facies display depleted compositions. The overall range of d34S values is remarkably higher than typical magmatic values, suggesting that sulfides formed from the reduction of seawater sulfate by bacteriogenic sulfate reduction in a closed or semi-closed system in the bedded ore, whereas thermochemical sulfate reduction likely played an important role in the feeder zone. The formation of the Mehdiabad deposit follows the evolution of the sedimentary basin. Abrupt lateral changes in facies and thickness, along with the existence of synsedimentary breccias and debris flows within the ore sequence, suggest the proximity to synsedimentary faults and tectonic activity contemporaneous with the sedimentation in the Lower Cretaceous, favorable for the formation of the ore deposit. The deposit formed from a combination of hydrothermal and syn-sedimentary processes. Sulfur isotopes, together with sedimentological, textural, mineralogical, and geochemical evidences, suggest that this deposit should be classified as a vent-proximal sub-seafloor replacement SEDEX ore deposit.Peer ReviewedPostprint (author's final draft

Optimum oil palm shell content as coarse aggregate in concrete based on mechanical and drying shrinkage properties / Mehdi Maghfouri

Oil palm shell (OPS) is a bio-solid waste in palm oil industry in tropical region which could be used as aggregate in concrete mixture. For more than three decades, OPS has been experimented as lightweight aggregate to produce lightweight aggregate concrete (LWAC). The use of this solid waste is not only a practical way to reduce the negative impact of the construction industry but also leads to a low-cost material. Medium and high strength LWAC using of OPS as coarse aggregate was successfully produced and reported by the researchers. However, high drying shrinkage at early and later ages is considered as a drawback for this type of concrete. From previous studies it was concluded that increasing the volume of OPS in concrete mixtures, leads to lower mechanical properties and higher drying shrinkage. In this regard, comprehensive experimental study was carried out to investigate the effect of partial replacement of crushed granite aggregates in normal-weight concrete (NWC) with OPS on mechanical properties and drying shrinkage behaviour in order to obtain the optimum level of OPS contribution in concrete mixture. For this study, six concrete mixes were designed using crushed granite and the OPS as coarse aggregates. The NWC by using of crushed granite aggregate and density of 2340 kg/m3 was considered as control concrete, and for all other mixes, crushed granite was partially replaced with OPS from 0 to 100% (by volume) with interval of 20% and a constant water to cement ratio of 0.33. The influence of curing condition on mechanical properties and drying shrinkage of concretes was also considered. Three different conditions of curing, namely, air curing (AC) to simulate the practical curing condition, 28 days’ water curing (28D) and 7 days curing in water and then air drying (7D) in the laboratory environment, are employed to examine 28-day compressive strength. The results of the study clearly indicated that up to 60% replacement of crushed granite aggregates by OPS in NWC, structural lightweight aggregate concrete with maximum drying shrinkage strain of approximately 500 micro-strain can be produced which is in allowable limit for drying shrinkage. Whereas in long-term ages (275 days) the value of drying shrinkage was 33% higher than the control mix. For mixes containing OPS beyond 60% the increment of shrinkage was significantly higher. Furthermore, for mixes containing up to 60% OPS, mechanical properties and final water absorption were satisfactory

Stratigraphic position, origin and characteristics of manganese mineralization horizons in the Late Cretaceous volcano-sedimentary sequence, south-southwest of Sabzevar

Introduction The Mn mineralization occurs in the northeastern segment of the Sabzevar zone (SZ), north of the Central Iranian Microcontinent (CIM). This Zone (SZ) is located between the CIM fragmentation in the south and the Kopeh dagh sedimentary sequence in the north. The ore deposits of the northeastern segment of the Sabzevar zone can be divided into three groups, each with different metal association and spatial distribution and each related to a major geodynamic event. The first mineralization with associated Ordovician host rock is characterized by Taknar polymetallic (Fe-rich) massive sulfide deposit. The Cretaceous mineralization consists of Cr deposits associated with serpentinized peridotites, Cyprus type VMS, Mn deposit in pillow lava, volcano-sedimentary hosted Besshi type VMS and Mn deposit. Paleogene mineralization in eastern segment of the Sabzevar zone began with porphyry deposits, Cu Red Bed mineralization occurs in the Paleogene sandy red marl. Materials and methods A field study and sampling was performed during the autumn of 2012. To assess the geochemical characteristics of 48 systematic samples (least fractured and altered) of ore-bearing layers and host rocks were collected from the deposit for polished thin section examination. In order to correctly characterize their chemical compositions, 15 least-altered and fractured samples were chosen for major elements analysis. Results The Late Cretaceous volcano-sedimentary sequence in south-southwest of Sabzevar hosts numerous manganese mineralization. The sequence based on the stratigraphic position, age and composition of the rocks, can be divided into two lower and upper parts. The lower part or K2tv unit mainly formed from marine sediments interbedded with volcanic rocks. The sedimentary rocks of this part include silicified tuff, chert, shale and sandstone, and the volcanic rocks involve pyroclastic rocks of various composition, rhyolite, dacite and andesitic lava. The upper part or LMV unit comprised of limestone, marl and volcanic rocks, overlies concordantly on the lower part (K2tv). The manganese mineralization within the host volcano-sedimentary sequence, based on stratigraphic position, relative age and type of host rocks involved the two horizons: the first horizon (Mn Ia, Ib) consisting of Benesbourd (Masoudi, 2008), Nudeh (Nasrolahi et al., 2012), Homaie (Nasiri et al., 2010), Goft and Manganese Gostar Khavar Zamin deposits, occurred in the lower part of the sequence (K2tv unit) and is hosted by red tuffs. The second horizon (Mn II) comprising of Zakeri (Taghizadeh et al., 2012), Cheshmeh Safeid, Mohammad Abad Oryan and Chah Setareh deposits, is hosted by marly-carbonate tuffs and locates within the upper part of the sequence (LMV unit) (Maghfouri, 2012). Geometry and shape of the ore bodies in various deposits are as stratiform, layered, parallel and concordant with layering of the host rocks. Textures of the ores include massive, lenticular, banded, laminated and disseminated. Mineralogy of the ores in the two ore horizons is simple and similar and is dominated by pyrolusite, psilomelane and braunite. Gangue minerals are predominantly the host rock-forming minerals including quartz, chlorite and feldspar. Discussion Geochemical data, structures and textures, stratigraphic position and lithologic characteristics of the host rocks represent that manganese reserves in south-southwest Sabzevar were formed as sedimentary-exhalative. Acknowledgements The authors are grateful to the Tarbiat Modares University Grant Commission for research funding. References Maghfouri, S., 2012. Geology, Mineralogy, Geochemistry and Genesis of Cu Mineralization within Late Cretaceous Volcano-Sedimentary Sequence in Southwest of Sabzevar, with emphasis on the Nudeh Deposit. M.Sc. Thesis, Tarbiat Modares University, Tehran, Iran, 312 pp. (in Persian) Masoudi, M., 2008. Geology, mineralogy, geochemistry and genesis of Benesbourd Mn deposit in the Southwest Sabzevar. M.Sc. Thesis, Tehran Islamic Azad University, Iran, 100 pp. (in Persian) Nasiri, F., Lotfi, M. and Jafari, M., 2010. Mineralogical studies on the Homaei manganese deposit in southwest of Sabzevar. 30th Symposium on Geosciences, Geological Survey of Iran, Tehran, Iran. (in Persian) Nasrollahi, S., Mousivand, F. and Ghasemi, H., 2012. Nudeh Mn deposit in the upper Cretaceous volcano- sedimentary sequence, Sabzevar subzone. 31th Symposium on Geosciences, Geological Survey of Iran, Tehran, Iran. (in Persian) Taghizadeh, S., Mousivand, F. and Ghasemi, H., 2012. Zakeri Mn deposit, example of exhalative mineralization in the southwest Sabzevar. 31th Symposium on Geosciences, Geological Survey of Iran, Tehran, Iran. (in Persian) <br

Paleontological study of the echinoderms in the qom formation (central iran)

The Qom formation was formed in the Oligo-Miocene during the final sea transgression in Central Iran (Figure 1). The best outcrop is located in the vicinities of the Qom City, approximately 130km at the south of Tehran. In general, the great heights of the zone are the result of intense tectonic activities. These heights have a number of faults and folds. Echinoderms are one of the most important and numerous fossil groups present in the Qom Formation and confirm the relationship of this environment with free waters. In the present investigation more than 100 prepared samples werestudied and 17 species were identified, scanned and classified. These fossils are more abundant in the upper part of the A member, which illustrates the abundance and diversity in C1 and C3 sub-membersbelonging to the C member. To classify these samples, classical and up-to-date methods were used.However, the systematic schemes were used more frequently (Moore, 1966; 1969-1971). Besides these studies, the other concomitant microfossils in the formation were investigated simultaneously to estimate the accurate age of them. It is concluded that the study of Oligo-Miocene Echinoderms present in the Qom formation is essential and important because, at the same time, the Central Iran Sea had a communicative role between the Indo-Pacific Ocean and the  Mediterranean Sea

Fine Motor Development of Low Birth Weight Infants Corrected Aged 8 to 12 Months

Objectives: The aim of this study was to compare the fine motor development between Low Birth Weight (LBW) infants and Normal Birth Weight infants (NBW) at the age of 8-12 months by using the Peabody Developmental Motor Scale-2 (PDMS-2) . Methods: This was a non experimental and cross sectional study which was conducted on the 18 LBW infants and 14 normal infants. By referring to the profile of infants in NICU of Aliasghar Hospital, those with defined inclusion criteria was recognized (case group). The normal weight infants, randomly selected from Health Center of that hospital, matched with case group for date of birth. After completing the questionnaire about demographic variables, their gross motor development was assessed with PDMS-2. Finally the scores of the motor quotient were analyzed by independent t-test statistical method. Results: There was a significant difference between Fine motor quotient of groups (P=0.007). Discussion: This study showed that LBW infants are significantly lower than normal weight infants in attaining Fine motor skills. It means that the LBW infants are more prone to developmental difficulties