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Phenopalynological Study of Some Ornamental Species in the Giza Region, Egypt Полный текст
2024
W. K. Taia, W. M. Amer, A. B. Hamed and A. M. Abd El-Maged
Mature flower buds were collected from twenty species planted on the different roads in the Giza district from May to September 2022 and 2023. The pollen grains were examined carefully and photographed using a 40x10x magnification lens in an OPTICA (B-150D) light microscope fitted with a USB digital video Camera and Computer Software. At least 30 pollen grains/each species were measured and described. Non-catalyzed pollens were sputtered onto Aluminum stubs, coated with 30 nm gold, and examined and photographed using JEOL JSL IT 200 SEM. The morphological characters of the pollen grains were examined. According to the pollen size Acalypha wilkesiana and Tecoma stans were the smallest pollen grains, from 20.0μm to 26.0μm, which facilitate their introduction to the nose causing asthma and rhinitis. Clerodendrum inerme pollen grains have echinate exine surface, which causes allergic symptoms more than the psilate ones. Plumbago capensis has intectate exine with echinate columella causing human disorders. This study demonstrates the critical position of air pollution in this area with the change in the phenological aspects of the plants resulting in producing immature pollen grains in huge amounts, which cause human disorders and pollinosis. Our results showed that the studied species can induce allergy in one way or another if we consider the situation of the studied area, weather pattern, and pollen characteristics.
Показать больше [+] Меньше [-]Mechanism and Behavior of Phosphorus Adsorption from Water by Biochar Forms Derived from Macadamia Husks Полный текст
2024
Nguyen Van Phuong
High phosphate content in water causes eutrophication, leading to many risks to the aquatic environment and human health. This study used biochar derived from macadamia husks at the pyrolysis temperatures (300, 450, and 600℃) to remove P from water. Adsorption parameters such as initial pH, biochar dosage, initial P concentration, and adsorption time when biochar was exposed to the P solution were determined. The results show that pH 4 is optimal for P removal with biochar pyrolyzed at 300 and 450°C, while pH 6 gives biochar 600°C, biochar dosage 10 g.L−1, concentration Initial P 25-200 mg.L−1 and adsorption time 40 minutes for 3 types of biochar. The maximum P adsorption capacity is 20.07, 20.03, and 20.03 mg.L−1 corresponding to 3 forms of biochar 300, 450, and 600°C. P adsorption data were consistent with the Freundlich isotherm model for all three biochar forms. The pseudo-second-order kinetic model was suitable for all three types of biochar, showing that the main adsorption mechanism is a surface chemical reaction. The study suggested that hydrogen bonding plays an important role in the adsorption of P onto biochar derived from macadamia husks. This study indicates that biochar derived from macadamia husks pyrolyzed at temperatures of 300, 450, and 600°C are all potentially effective and low-cost adsorbents for phosphate removal from water.
Показать больше [+] Меньше [-]Phytochemistry of Aloe vera: A Catalyst for Environment-Friendly Diverse Nanoparticles with Sustained Biomedical Benefits Полный текст
2024
S. Yadav, A. Khan and J. G. Sharma
Nanotechnology has become one of the most active fields in the research area and is getting more attention toward nanoparticle synthesis. Green synthesis methods using various plants, fungi, bacteria, and algae were used to synthesize nanoparticles with proper requirements and maintain sterile conditions to get the desired products. Aloe vera, a bio-medicinal plant, contains a wide range of phytochemicals such as phenolic, hydroxyl groups, alkaloids, polyols, polysaccharides, etc, which act as reducing and capping agents with high efficiency. This review revealed that aloe vera-derived nanoparticles are safe, stable, cost-effective, and eco-friendly, and they also possess significant applications for drug targeting, disease resistance, tissue engineering, wound healing, anticancer, antibacterial, and cosmetic industries. Synthesized metal nanoparticles are characterized through UV-visible spectroscopy, X-ray diffraction, scanning electron and transmission electron microscopy, photoluminescence, and the Well-diffusion method. It is highly interesting to note that aloe vera-mediated silver and zinc nanoparticles possess high potency against multi-drug resistant pathogens. Here, anticancer, antioxidant, anti-inflammatory, and photocatalytic activity separately showed by aloe vera peel, gel, and leaf, along with possible challenging situations faced during plant extract-based nanoparticle synthesis, are highlighted. Additionally, the introduction of GMOs is subjected to play an important role in advancing green methods. However, more research is required to estimate the dose’s safety, degradation, and synergistic mechanism inside the human body for better use of the green method for the treatment of microbial infections.
Показать больше [+] Меньше [-]Exploring the Water Crisis and Viability of Unregulated Groundwater in India: An Analysis Полный текст
2024
Aditi Nidhi and J. Lakshmi Charan
Water conservation and management are significant features of ancient Indian Vedic culture. However, India’s rapid industrialization, globalization, and urbanization have posed a serious threat to this practice. Many metropolitan cities and other cities will likely have groundwater depletion in the near future. As per the ‘United Nations University - Institute for Environment and Human Security (UNU-EHS)’ report titled “The 2023 Interconnected Disaster Risks Report”, India is close to reaching its tipping point of groundwater depletion. It also highlighted that 27 of 31 major global aquifers are depleting faster than they can be replenished. A combination of factors, including climate change, private land ownership, mechanical pumping, etc., led to the depletion of groundwater and water scarcity for farming and other purposes. Additionally, NITI Aayog and the Central Water Commission have released several reports that highlighted the plight of the country’s aquifers. India’s groundwater resources are not only a potential source for agricultural, domestic, and industrial needs in the country but also a threat to its sustainable development and equitable distribution. At present, there is no central law on the groundwater regulation. Although the Model Groundwater (Sustainable Management) Bill 2017 is an affirmative step, its effectiveness depends on implementation by state governments, the establishment of robust local institutions, and removing political incentives from groundwater management. Until now, landowners have enjoyed monopolistic access to groundwater due to common laws that recognize uncontrolled rights over the resources. These restrictions have perpetuated gross inequities in accessing groundwater, which makes a remarkable shift from previous laws. This paper evaluates India’s existing groundwater laws to achieve sustainability, equity, and the effective execution of water rights. It also delves into the lacunae in the existing laws and suggestive measures to control the challenges of groundwater in India.
Показать больше [+] Меньше [-]An Experimental Investigation on Sustainable Concrete Made with Refractory Brick as a Substitute of Natural Fine Aggregate Полный текст
2024
Sanjeet Kumar, Md Asfaque Ansari, Lakshmi Kant and Nitya Nand Jha
In the face of the pressing global issue of waste management and the diminishing availability of natural resources, the management of non-biodegradable waste materials, including brick waste, poses significant challenges. Ineffective disposal practices not only create logistical obstacles but also pose health hazards. This study explores the potential of utilizing waste refractory bricks (RB) as a sustainable substitute for natural fine aggregates in concrete production. Various experimental investigations were conducted to evaluate the feasibility and performance of RB sand in concrete mixtures. Tests included assessments of fresh and hardened properties, such as slump values, compressive strength, tensile strength, flexural strength, and resistance to elevated temperatures. The research revealed that RB sand, when used as a partial replacement for fine aggregates, can significantly enhance the compressive strength of concrete, with optimal results observed at a 30% replacement level. Moreover, RB-based concrete exhibited improved split tensile strength compared to traditional concrete, particularly at replacement levels of 10% to 30%. Flexural strength also showed notable improvements, with the 40% replacement level demonstrating optimal performance. Additionally, the study investigated the effects of elevated temperatures on concrete specimens and found that RB-based sustainable concrete showed higher compressive strength retention compared to conventional concrete at a 30% replacement level. Furthermore, weight variation analysis indicated that RB-based concrete had a lower density compared to traditional concrete. Overall, the findings suggest that incorporating RB sand in concrete mixtures could offer a promising solution for sustainable construction practices, contributing to environmental conservation and human health preservation by reducing reliance on natural aggregates and minimizing adverse environmental impacts.
Показать больше [+] Меньше [-]Use of Geopolymerized Fly Ash with GGBS as a Barrier for Waste Containment Facilities Полный текст
2024
S. S. S. Saranya and S. N. Maya Naik
The present paper reports the results of experimental investigations performed to examine the feasibility of using fly ash (FA) and ground-granulated blast furnace slag (GGBS) geopolymers as barrier materials for waste containment facilities. The alkaline geopolymer is a blend of FA and GGBS with sodium hydroxide in concentrations varying from 1 to 5. The important properties of most barrier materials include strength and hydraulic conductivity. While FA can develop compressive strength through pozzolanic reactions, polymerized FA develops tensile strength. For the construction of barriers for landfills with higher heights, tensile strength assumes importance. To further improve the strength, FA can be amended with GGBS. Results indicate that the FA-GGBS mixture in the ratio of 40:60, when cured, exhibited higher strength at any molar concentration. Further, the hydraulic conductivity of the material, which is predominant for barriers in waste containment facilities, is studied. To examine the impact of the presence of heavy metals in the leachates, batch adsorption studies were executed on a 40% FA- 60% GGBS mixture. Leachate with nickel and lead were adapted for their retention within the barrier. It has been observed that the geopolymerized FA and GGBS can retain ionic metals. The retention capacity of heavy metals is due to their precipitation in the voids of the barrier material enabling further reduction in the hydraulic conductivity making geopolymer a sustainable barrier material.
Показать больше [+] Меньше [-]The Circular Economy of the Food Bank Supply Chain in Bandung City, West Java Полный текст
2024
Sri Widiyanesti and Bintang Mahardhika
Food banks play a crucial role in reducing food waste and addressing food vulnerability. Their operations involve an efficient supply chain that collects surplus food, processes it, and distributes it to those in need. This aligns with the goals of a circular economy, aiming to minimize food crises. This research aims to understand the supply chain of the Food Bank Bandung and analyze the implementation of circular economy principles within its supply chain. The study employs qualitative methods, with data gathered through interviews conducted with representatives from the Food Bank located in Bandung City. The collected information was used to design a comprehensive supply chain model, which was then meticulously analyzed. The analysis reveals that the Food Bank in Bandung effectively implements a circular economy by transforming surplus food, which would otherwise go to waste, into consumable items. Furthermore, the food bank adopts circular economy concepts by providing inedible food to Black Soldier Fly (BSF) cultivation for maggot consumption, which then can be used as an alternative source of protein for animal feed. The findings of the study show how circular economy practices can be integrated into food bank operations. By analyzing the circular economy approach in the Food Bank of Bandung, this research contributes to the existing body of knowledge and provides a foundation for future studies, offering a more extensive dataset for researchers and practitioners in the field.
Показать больше [+] Меньше [-]Assessment of 40K and Heavy Metal Levels in Euphrates River of Al-Qadisiyah Governorate Полный текст
2024
S. K. Ibrahiem and H. A. Walli
The objective of the current research is to measure the specific activity of 40K and heavy metals in the water samples collected from the Al-Diwaniyah River in Al-Qadisiyah Governorate, Iraq. The activity of 40K in water samples was ascertained using High Purity Germanium Spectrometer (HPGe) detector technology, which is based on a high-resolution gamma spectrometry system, and by using an atomic absorption spectrometer (A.A.S.) to determine the heavy metals of Ni, Cd and Pb, as well as measure some of the physical properties of water samples. The results indicated the concentration of 40K in the water was presented in different concentrations. The lowest value was 2.6±0.5 Bq/L Al-Muhanawiyah, while the highest value was in Al-Diwaniyah center 24.6± 4.0Bq/L. On the other hand, the highest results of Pb, Cd and Ni have been 0.1247, 0.0652 and 0.157 ppm, respectively. While, the results of physics properties were from 7.05 to 8.3 for total dissolved solids (T.D.S.) values were from 2100 to 756.6 mg/L, electrical conductivity values were between 1140 and 3500 μs/cm, and turbidity values were between 7.0 and 54.5. Based on the results, the concentrations of the 40K and heavy metals indicated that the results are almost slight compared to internationally accepted values.
Показать больше [+] Меньше [-]Conversion of Citrus Fruit Peel into a Value-Added Product, Bio-Oil Полный текст
2024
M. Subathra and R. Devika
The present study aimed to investigate the bio-oil from the blended citrus fruit peel by hydrothermal liquefaction process. Huge amounts of fruit peel waste are disposed of in the open environment without any proper management. Such fruit peels are considered a potential bio-resource to be converted into economically valuable products like bio-oil. Since the citrus fruit peel is a rich source of moisture content, a hydrothermal liquefaction process was introduced to produce bio-oil from cellulose, and lignocellulose. The experimental design against temperature, time, and biomass concentration optimization was carried out which was confirmed by the ANOVA f and p test that reveals time and temperature influenced the bio-oil yield drastically. As the time and temperature rise more than 60 min and 280°C, the volatile substance present in the biomass converts itself into solid residue which has a negative impact on bio-oil production, compared with biomass concentration. The maximum yield of bio-oil was recorded as 29.4% at 280°C at 60min reaction time and 80g/200mL concentration as optimized parameters. The GCMS reveals the presence of hydrocarbons and alkanethiol which are flammable and hold the standards of commercial transportation fuel but hold nitrogen and oxygen-containing compounds to pull down the fuel standards. Thus, the produced bio-oil can be blended with the transportation fuel after the upgradation process for efficient results.
Показать больше [+] Меньше [-]Analysis of CMIP6 Simulations in the Indian Summer Monsoon Period 1979-2014 Полный текст
2024
Lakshmana Rao Vennapu, Krishna Dora Babu Kotti, Sravani Alanka and Pavan Krishnudu Badireddi
The monsoon system in India plays a pivotal role in shaping the country’s climate. Recent studies have indicated that the increasing variability of monsoons is attributable to climate change, resulting in prolonged periods of drought and excessive rainfall. Understanding, analyzing, and forecasting monsoons is crucial for socioeconomic sustainability and communities’ overall well-being. Climate forecasts, which project future Earth climates typically up to 2100, rely on models such as the Couple Model Intercomparison Project (CMIP). However, confidence in these forecasts remains low due to the limitations of global climate models, particularly in terms of capturing the intricacies of monsoon dynamics, notably from June to September. To address this issue, researchers have examined precipitation simulations under various future scenarios using both CMIP5 and the latest CMIP6 models. Evaluating the performance of these models from 1979 to 2014, particularly in simulating mean precipitation and temperature, has revealed improvements in multi-model ensembles (MME), highlighting advancements in monsoon characteristics. By comparing the CMIP5 and CMIP6 models, researchers have identified the most reliable models for climate downscaling research, which can provide more accurate predictions of regional climate changes, thereby offering valuable insights for enhancing climate modeling in the Indian subcontinent.
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