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"Rahman, Ismail"
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Awareness and challenges of building information modelling (BIM) implementation in the Yemen construction industry
PurposeThis paper aims to investigate the awareness of construction practitioners of the adoption of building information modeling (BIM) and identification of the dominant challenges of implementing BIM in the life cycle of a construction project.Design/methodology/approachThis study was sequentially conducted in the following in three main phases: a preliminary study of archival literature, where a rigorous study of the literature was conducted to identify the challenges of adopting BIM in the construction industry which was to be applied later to the challenges in the case of the Yemen construction industry; data collection, where data were collected using a questionnaire survey targeting 123 Yemeni construction practitioners working in managerial and technical levels; and data analysis, where data were analyzed using descriptive analysis by calculating the average index and standard deviations. The data were analyzed using the SPSS software.FindingsThe results show that the most critical challenges to adopt BIM are financial restrictions, lack of BIM knowledge, improper introduction of BIM concepts, lack of awareness of BIM benefits and no governmental enforcement. The study recommends policymakers and construction players to consider the challenges for a better introduction of BIM in the Yemen construction industry.Research limitations/implicationsThis research focuses on the awareness and challenges of implementing BIM in the Yemen construction industry.Practical implicationsThe findings of this study will help policymakers develop more constructive strategies to reduce the challenges and introduce governmental agendas towards the widespread use of the BIM concept and technology in the Yemen construction industry. The study suggested an in-depth investigation into the current curriculum in the Yemen universities and recommended the introduction of BIM concept in engineering courses.Social implicationsThis study focused on the challenges of implementing BIM and the role of the social aspect in the issue.Originality/valueFrom the extensive review of previous findings, this paper concentrates on the challenged to the implementation of BIM in the Yemen construction industry. There are lack of investigative studies that focus on the introduction of new technologies to advance the Yemen construction sector. Therefore, the findings help the authority to diagnose and address the sources of these challenges and introduce new solutions to the industry.
Journal Article
Synthesis of Silica Nanoparticles by Sol-Gel: Size-Dependent Properties, Surface Modification, and Applications in Silica-Polymer Nanocomposites—A Review
Application of silica nanoparticles as fillers in the preparation of nanocomposite of polymers has drawn much attention, due to the increased demand for new materials with improved thermal, mechanical, physical, and chemical properties. Recent developments in the synthesis of monodispersed, narrow-size distribution of nanoparticles by sol-gel method provide significant boost to development of silica-polymer nanocomposites. This paper is written by emphasizing on the synthesis of silica nanoparticles, characterization on size-dependent properties, and surface modification for the preparation of homogeneous nanocomposites, generally by sol-gel technique. The effect of nanosilica on the properties of various types of silica-polymer composites is also summarized.
Journal Article
Effect of Extraction Variables on the Biodegradable Chelant-Assisted Removal of Toxic Metals from Artificially Contaminated European Reference Soils
Development of aminopolycarboxylate chelants (APCs) having enhanced biodegradability is gaining increasing focus to replace the EDTA and its homologs with those used widely for the ex situ treatment of contaminated soils and are potential eco-threats. The paper reports the chelant-assisted extraction of the toxic metals (Cd, Cu, Pb, and Zn) from the metal-spiked European reference soils (Eurosoil 1 and Eurosoil 4) using biodegradable APCs, namely EDDS, GLDA, and HIDS. The effects of chelant-to-metal molar ratio, solution pH, and metal/chelant stability constants were evaluated, and compared with that of EDTA. The selectivity aptitude of the biodegradable chelants towards the toxic metals was assumed from the speciation calculations, and a proportionate correlation was observed at neutral pH. Pre- and post-extractive solid phase distributions of the target metals were defined using the sequential extraction procedure and dissolution of metals from the theoretically immobilized fraction was witnessed. The effect of competing species (Al, Ca, Fe, Mg, and Mn) concentrations was proven to be minimized with an excess of chelant in solution. The highlight of the outcomes is the superior decontamination ability of GLDA, a biodegradable APC, at minimum chelant concentration in solution and applicability at a wide range of pH environments.
Journal Article
Human health risk assessment due to consumption of dried fish in Chennai, Tamil Nadu, India: a baseline report
The current study sought to determine the levels of radioactivity and heavy metal contamination in 22 dried fish samples collected in Chennai, Tamil Nadu. The study found that there were substantial heavy metals concentrations for Pb, Mn, Cr, Co, and Cd. The concentration of heavy metal Pb being alarmingly high (32.85 to 42.09 mg/kg), followed by Cd (2.18 mg/kg to 3.51 mg/kg) than the permissible limit of WHO (2.17 mg/kg) for Pb and (0.05 mg/kg) for Cd. In terms of radioactivity, the gross alpha activity in the dried fish samples ranged 6.25 ± 0.12 to 48.21 ± 0.11 Bg/kg with an average of 20.35 Bg/kg and with a gross beta activity from 6.48 ± 0.02 to 479.47 ± 0.65 Bg/kg, for an average of 136.83 Bg/kg. The study found that the internal radiation dose that people receive upon consuming the fish species
Sphyraena obtusata
,
Rachycentron canadum
,
Lepidocephalichthys thermalis
,
Synodontidae
,
Carangoides malabaricus
,
Sardina pilchardus
,
Scomberomorus commerson
,
Sillago sihama
,
Gerres subfasciatus
, and
Amblypharyngodon mola
is above the ICRP-recommended limit of less than 1 mSv/year. Annual gonadal dose equivalent (AGDE) and total excessive lifetime cancer risk (ELCR) ranged 0.488 µSv year
−1
and 0.004 µSv year
−1
respectively, the values of AGDE being higher than the global average value. The findings of the study indicate that the analyzed dried fish samples are contaminated with Pb and Cd, which shall pose cancer risk to the consumers as a result.
Journal Article
Physiological responses of wild grass Holcus lanatus L. to potentially toxic elements in soils: a review
Potentially toxic elements (PTEs) in soils accumulate in plants, obstruct their growth, and pose hazards to the consumer via the food chain. Many kinds of grass, grass-like plants, and other higher plant species have evolved a tolerance to PTEs.
Holcus lanatus
L., a wild grass, is also tolerant (an excluder) of PTEs, such as arsenic (As), cadmium (Cd), lead (Pb), and zinc (Zn). However, the extent of tolerance varies among ecotypes and genotypes. The PTE tolerance mechanism of
H. lanatus
curtails the typical uptake process and causes a reduced translocation of PTEs from the roots to the shoots, while such a characteristic is useful for contaminated land management. The ecology and response patterns of
Holcus lanatus
L. to PTEs, along with the associated mechanisms, are reviewed in the current work.
Journal Article
Effect of natural radioactivity along the southern coastal area of Tamil Nadu with statistical approach
Natural radioactivity was assessed in sediment samples collected along southern coastline of Tamil Nadu. Average activity concentrations of
238
U,
232
Th, and
40
K were determined (29 ± 3, 218 ± 6, and 80 ± 5 Bq kg
–1
, respectively). Calculated parameters included radium equivalent activity (347 ± 12 Bq kg
–1
), absorbed dose rate (273 ± 10 nGy h
–1
), annual effective dose rate (0.33 ± 0.01 mSv y
–1
), external hazard index (0.94 ± 0.03), annual gonadal dose equivalent (1026 ± 35 mSv y
–1
), and excess lifetime cancer risk (1.17 ± 0.03). Multivariate statistical analyses were employed to examine correlations among the radioactive variables. The presence of heavy minerals in the samples was confirmed using X-ray diffraction.
Journal Article
Synthesis and Characterization of Spherical Calcium Carbonate Nanoparticles Derived from Cockle Shells
Cockle shells are a natural reservoir of calcium carbonate (CaCO3), which is widely used in bone repair, tissue scaffolds, and the development of advanced drug delivery systems. Although many studies report on the preparation of CaCO3, the development of a nanosized spherical CaCO3 precursor for calcium oxide (CaO) that is suitable to be incorporated in dental material was scarce. Therefore, this study aimed to synthesize a nanosized spherical CaCO3 precursor for CaO derived from cockle shells using a sol–gel method. Cockle shells were crushed to powder form and mixed with hydrochloric acid, forming calcium chloride (CaCl2). Potassium carbonate (K2CO3) was then fed to the diluted CaCl2 to obtain CaCO3. The effect of experimental parameters on the morphology of CaCO3, such as volume of water, type of solvents, feeding rate of K2CO3, and drying method, were investigated using field-emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray diffractometry (XRD), Brunauer–Emmett–Teller surface area analysis, and thermogravimetric analysis. Optimized CaCO3 was then calcined to form CaO. XRD analysis of CaCO3 nanoparticles was indicative of the formation of a calcite phase. The well-structured spherical shape of CaCO3 was obtained by the optimum condition of the addition of 50 mL of water into CaCl2 in ethanolic solution with a 1 h feeding rate of K2CO3. Less agglomeration of CaCO3 was obtained using a freeze-drying technique with the surface area of 26 m2/g and average particle size of 39 nm. Spherical shaped nanosized CaO (22–70 nm) was also synthesized. The reproducibility, low cost, and simplicity of the method suggest its potential applications in the large-scale synthesis of the nanoparticles, with spherical morphology in an industrial setting.
Journal Article
Evaluation of newly designed flushing techniques for on-site remediation of arsenic-contaminated excavated debris
Excavated debris (soil and rock) contaminated with geogenic arsenic (As) is an increasing concern for regulatory organizations and construction stakeholders. Chelator-assisted soil flushing is a promising method for practical on-site remediation of As-contaminated soil, offering technical, economic, and environmental benefits. Ethylenediaminetetraacetic acid (EDTA) is the most prevalent chelator used for remediating As-contaminated soil. However, the extensive environmental persistence and potential toxicity of EDTA necessitate the exploration of eco-compliant alternatives. In this study, the feasibility of the conventional flushing method
pump-and-treat
and two newly designed
immersion and sprinkling
techniques were evaluated at the laboratory scale (small-scale laboratory experiments) for the on-site treatment of As-contaminated excavated debris. Two biodegradable chelators, L-glutamic acid-N,N′-diacetic acid (GLDA) and 3-hydroxy-2,2′-iminodisuccinic acid (HIDS), were examined as eco-friendly substitutes for EDTA. Additionally, this study highlights a useful post-treatment measure to ensure minimal mobility of residual As in the chelator-treated debris residues. The pump-and-treat method displayed rapid As-remediation (
t
, 3 h), but it required a substantial volume of washing solution (100 mL g
−1
). Conversely, the immersion technique demonstrated an excellent As-extraction rate using a relatively smaller washing solution (0.33 mL g
−1
) and shorter immersion time (
t
, 3 h). In contrast, the sprinkling technique showed an increased As-extraction rate over an extended period (
t
, 48 h). Among the chelators employed, the biodegradable chelator HIDS (10 mmol L
−1
; pH, 3) exhibited the highest As-extraction efficiency. Furthermore, the post-treatment of chelator-treated debris with FeCl
3
and CaO successfully reduced the leachable As content below the permissible limit.
Journal Article
Polycyclic aromatic hydrocarbons in ship breaking area and associated ecological risk assessment: evidence from the Sitakund ship-breaking area in Bangladesh
Ship-breaking yards are recognized for releasing hazardous polycyclic aromatic hydrocarbons (PAHs), leading to severe environmental pollution in the sediment of ship-breaking areas. This study assessed the concentrations of 16 priority PAHs in surface sediments collected from the intertidal zone adjacent to the Sitakund ship-breaking yards. The samples underwent Soxhlet extraction and detection using PerkinElmer GC-Clarus 690 and MS-Clarus SQ8C with an Elite-5MS capillary column (30 m × 0.25 mm ID × 0.25 µm). The study utilized PAH concentrations to reveal spatial distribution patterns, identify point sources, and assess potential toxicity. The total PAH concentration ranged from 1899.2 to 156,800.08 ng g
−1
dw, while the concentration of 7 carcinogenic PAHs ranged from 822.03 to 1899.15 ng g
−1
dw. High molecular weight PAHs dominated among the 16 PAHs, whereas low molecular weight PAHs, such as 2-ring PAHs, were negligible. Source characterization based on different molecular ratios suggested that PAHs in the area originated from pyrolytic processes related to ship dismantling, fishing activities, and water transportation for people. The observed PAH concentrations exceeded both national and international standards for sedimentary PAH levels, indicating significant ecological risks. The total TEQcarc values of sediment samples varied from 564.41 to 10,695.12 ng g
−1
, with a mean value of 3091.25 ng g
−1
. The study’s findings underscore the immediate biological damage that PAH contamination in the Sitakund ship-breaking area could cause, emphasizing the need for effective control measures to ensure ecological and human safety.
Journal Article