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Production of Spirulina platensis Using Inexpensive Local Resources in Palestine

Journal of Environmental Protection 2024年第3期15卷 357-377页

作者： Imad Al-Jabali ahmad qutob Mahmoud Alkhatib Mutaz qutob Department of Environment and Earth Studies Al-Quds University Jerusalem Palestine Department of Electrical Engineering Faculty of Engineering Al-Quds University Jerusalem Palestine Department of Chemistry and Chemical Technology Al-Quds University Jerusalem Palestine

Spirulina platensis is a special and unique cyanobacteria that is produced worldwide with a varied cost of cultivation media. In this study, five main experiments with different treatments were performed to evaluate the possibility of using cheap aquaculture water for Spirulina production, to test if solutions made by plant ash (PAS) could be used for Spirulina production, to determine if brackish water (BW) and mining water have a good impact on Spirulina production, to create a medium composed of cheap chemicals and fertilizers to be used for Spirulina cultivation, and to test if a mixture made from local components could be used to produce Spirulina. All experiments were performed via growth and dry weight measurements, including determination of chemical and physical characteristics of the samples with a comparison with Zarrouk medium (ZM) as a reference for each experiment, and all experiments were performed for 21 days to determine the best media type that lasts longer for commercial purposes. In all experiments, pH values were between 8 and 11, and EC was between 9.8 and 30 ms/cm, while temperature was at 30°C and 35°C, and light was at 1500 and 5000 Lux for 16 h light and 8 h dark. Spirulina can grow in (FW). It can also grow in FW diluted with BW. Also a 3% PAS can be used as a source to cultivate Spirulina at a very low price compared to ZM. The chemical fertilizer formula was one of the best types among all treatments with a good price. A mixture of these local resources could be a very good cheap alternative source. The main result that was obtained from all experiments in this study is the ability of Spirulina to grow within a wide range of chemical parameters at a lower price.

关键词： Spirulina platensis Tilapia Brackish Water Zarrouk Medium

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Determination of Different Trace Heavy Metals in Children’s Plastic Toys Imported to the West Bank/Palestine by ICP/MS-Environmental and Health Aspects

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Journal of Environmental Protection 2014年第12期5卷 1104-1110页

作者： Mutaz Al-qutob ahmad Asafra Tharwat Nashashibi ahmad A. qutob Department of Earth and Environmental Studies Faculty of Science and Technology Al-Quds University Jerusalem Aquatic and Aquaculture Research Laboratory Al-Quds University Jerusalem Department of Electronic Engineering Faculty of Engineering Al-Quds University Jerusalem

The main aim of this study is to assess the quality of inexpensive plastic toys imported to Palestinian Markets. The content of heavy metals (Pb, Cd, Cr, Hg, As, Se, Ba, and Zn) was analyzed in 50 plastic toys purchased from local markets in Palestine and 17 plastic toys purchased from Israeli markets for comparison. After the digestion of samples with concentrated nitric acids and hydrogen peroxide using a microwave digester, the concentrations of the selected heavy metals were determined by ICP-MS Agilent 7500 in Al-Quds University. Results revealed that 40% of the Palestinian toy samples had high concentration (above international limits) of Pb, 30% of Cd, 34% of Cr, 6% of Hg, 42% of As, 32% of Se, 20% of Ba, and 40% of Zn. On the other hand, 95% of the Israeli samples were safe, and their concentrations were less than the maximum internationally allowable limits. In the same context, ten toy samples (2.5 gm each) had been crushed and dipped for 8 hours in a solution of artificial saliva. The solution was acidified and tested for heavy metal concentrations, but none of the migration concentrations exceeded the international maximum allowable limit. High levels of heavy metal concentrations, found in the plastic toys from the Palestinian markets could form a health hazard to children and put their lives at risk. It could be also an indirect source for environmental pollution.

关键词： Plastic Toys Heavy Metals Content Palestinian Markets Israeli Markets

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Heavy Metals Concentrations in Leafy Vegetables in Palestine, Case Study: Jenin and Bethlehem Districts

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Journal of Environmental Protection 2022年第1期13卷 97-111页

作者： Mahmoud AlKhatib ahmad qutob Elizabeth Kattan Husam Malassa Mutaz qutob Department of Chemistry and Chemical Technology Al-Quds University Jerusalem Palestine Department of Electrical Engineering Faculty of Engineering Al-Quds University Jerusalem Palestine Department of Environment and Earth Studies Al-Quds University Jerusalem Palestine

This study investigates the concentrations of metals in leafy vegetables in Bethlehem and Jenin districts in Palestine. The concentrations of Fe, Pb, Cr, Co, Cu, Mn, Cd, and Zn were measured. Vegetables including spinach, arugula, and parsley were collected from different farms from both regions, and analyzed by using ICP-MS. In Bethlehem region, Iron concentrations were ranged from 25 to 1046 mg/kg. Iron concentrations were higher than the WHO/FAO limits of 425 mg/kg in 33% of the samples. Lead concentrations were ranged from 0.04 to 1.77 mg/kg. Lead concentrations were higher than the WHO/FAO limits of 0.3 mg/kg in 40% of the samples. Chromium concentrations were ranged from 0.02 to 2.51 mg/kg. Chromium concentrations were higher than the WHO/FAO limits of 1.3 mg/kg in 13% of the samples. Zinc concentrations were ranged from 4 to 107 mg/kg. Zinc concentrations were higher than the WHO/FAO limits of 99.4 mg/kg in 6.6% of the samples. Cadmium concentrations were ranged from 0.01 to 1.4 mg/kg. Cadmium concentrations were higher than the WHO/FAO limits of 0.2 mg/kg in 13% of the samples. The concentration of Manganese, Cobalt and Cupper were all below the WHO/FAO limits of 500, 50 and 73 mg/kg respectively. In Jenin region, Iron concentrations were ranged from 42 to 543 mg/kg. Iron concentrations were higher than the WHO/FAO limits of 425 mg/kg in 20% of the samples. Lead concentrations were ranged from 0.05 to 0.67 mg/kg. Lead concentrations were higher than the WHO/FAO limits of 0.3 mg/kg in 20% of the samples. Copper concentrations were ranged from 0.62 to 278 mg/kg. Copper concentrations were higher than the WHO/FAO limits of 73 mg/kg in 6.66% of the samples. Cadmium concentrations were ranged from 0.02 to 1.62 mg/kg. Cadmium concentrations were higher than the WHO/FAO limits of 0.2 mg/kg in 6.66% of the samples. The concentration of Chromium, Manganese, Cobalt and Cupper were all below the WHO/FAO limits. It was concluded that the contamination found in some leaf

关键词： Heavy Metals Vegetables Pesticides

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Evaluation of Heavy Metal Concentrations in Soil and Edible Vegetables Grown in Compost from Unknown Sources in Al-Jiftlik, Palestine

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Journal of Environmental Protection 2022年第1期13卷 112-125页

作者： Mohammed Bawwab ahmad qutob Mahmoud Al Khatib Husam Malassa Ayman Shawahna Mutaz qutob Department of Materials Engineering Faculty of Engineering Al-Quds University Jerusalem Palestine Department of Electrical Engineering Faculty of Engineering Al-Quds University Jerusalem Palestine Department of Chemistry and Chemical Technology Al-Quds University Jerusalem Palestine Environment Quality Authority Al-Bireh Palestine

The use of compost as a fertilizer has been widely used in many countries. However, compost that contains heavy metals can transfer these metals to soils and plants (vegetables). This study investigates the concentrations of metals in soil and edible vegetables that were fertilized by polluted unknown compost in Al-Jiftlik region (Palestine). The source of the compost is the autocratic dumping sites of the Israeli settlements. The compost is distributed free of charge to the Palestinian farmers. The concentrations of Ba, Cu, Pb, Th, Se, Mn, Co and As in the contaminated farms were measured. Vegetables include: Eggplant, Corn, Bell Pepper, Cucumber and Marrow. Metals availability as well as the pH, was also examined in the soil samples. Normal farms that did not use this unknown compost were used as a reference. The concentrations of Ba, Cu, Pb, Th, Se, Mn, Co and As in soil and vegetables in the polluted farms were above the WHO limits. Barium concentrations in the vegetables were ranged from 1.00 mg/kg to 0.453 mg/kg. It is high when compared to WHO limit of 0.3 mg/kg. Copper concentrations in the vegetables were ranged from 63.84 mg/kg to 50.53 mg/kg. It is high when compared to WHO limit of 40 mg/kg. Lead concentrations in the vegetables were ranged from 1.00 mg/kg to 0.453 mg/kg. Lead concentration is high when compared to WHO limit of 0.3 mg/kg. Thallium concentrations in the vegetables were ranged from 2.99 mg/kg to 1.22 mg/kg. Thallium concentration is high when compared to WHO limit of 0.3 mg/kg. Selenium concentrations in the vegetables were ranged from 0.550 mg/kg to 0.348 mg/kg. It is high when compared to WHO limit of 0.3 mg/kg. Manganese concentrations in the vegetables were ranged from 825.3 mg/kg to 446.2 mg/kg. It is almost high when compared to WHO limit of 500 mg/kg. Cobalt concentrations in the vegetables were ranged from 1.119 mg/kg to 0.522 mg/kg. Cobalt concentration is high when compared to WHO limit of 0.1 mg/kg. A

关键词： Compost Heavy Metals Vegetables Autocratic Dumping

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Rotating effects on the thermophysical properties of a two-dimensional GaAs quantum ring

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Communications in Theoretical Physics 2024年第6期76卷 165-173页

作者： ahmad Ghanbari Department of Physics College of ScienceYasouj UniversityYasoujIran

In this work,we have investigated the rotating effect on the thermodynamic properties of a 2D quantum ***,we have considered the radial potential of a 2D quantum ring and solved the Schrödinger equation in the presence of the Aharonov-Bohm effect and a uniform magnetic field for the considered *** to the solution of the equation,we calculated the eigenvalues and eigenfunctions of the considered *** the calculated energy spectrum,we obtained the partition function and thermodynamic properties of the system,such as the mean energy,specific heat,entropy and free *** results show that the rotating effect has a significant influence on the thermophysical properties of a 2D quantum *** also study other effects of the rotating term:(1)the effect of different values of rotating parameters,and(2)the effect of negative rotation on the thermodynamic properties of the *** results are discussed in detail.

关键词： Schrodinger equation quantum ring rotation effect thermophysical properties

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Finite element model updating for structural damage detection using transmissibility data

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Earthquake Engineering and Engineering Vibration 2024年第1期23卷 87-101页

作者： ahmad Izadi Akbar Esfandiari Department of Maritime Engineering Amirkabir University of TechnologyTehran 15875-4413Iran

This paper presents a new finite element model updating method for estimating structural parameters and detecting structural damage location and severity based on the structural responses(output-only data).The method uses the sensitivity relation of transmissibility data through a least-squares algorithm and appropriate normalization of the extracted *** proposed transmissibility-based sensitivity equation produces a more significant number of equations than the sensitivity equations based on the frequency response function(FRF),which can estimate the structural parameters with higher *** abilities of the proposed method are assessed by using numerical data of a two-story two-bay frame model and a plate structure *** evaluating different damage cases,the number,location,and stiffness reduction of the damaged elements and the severity of the simulated damage have been accurately *** reliability and stability of the presented method against measurement and modeling errors are examined using error-contaminated *** parameter estimation results prove the method’s capabilities as an accurate model updating algorithm.

关键词： damage detection model updating output-only transmissibility sensitivity equation

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Correlation between structural phase transition and physical properties of Co^(2+)/Gd^(3+)co-substituted copper ferrite

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Journal of Rare Earths 2024年第7期42卷 1344-1353,I0006页

作者： Mohsen Choupani ahmad Gholizadeh School of Physics Damghan UniversityDamghan36716-45667Iran

The doping of the spinel ferrites with selective cations usually improves the properties of the parent *** effect of Co^(2+)/Gd^(3+)co-substitution on the microstructure,optical,and magnetic properties of Cu1-xCoxFe2-xGdxO4 prepared by the citrate-nitrate auto-combustion synthesis was *** of the samples was performed with powder X-ray diffraction(XRD),Raman and Fouriertransform infrared(FTIR)spectroscopy,field-emission scanning electron microscopy,X-ray energydispersive spectroscopy,UV-Vis spectroscopy,and a vibrating sample *** results of XRD,Raman,and FTIR analysis show a gradual structural phase transition from a tetragonal(I41/amd)structure to a cubic(Fd3m)*** bandgap energy of the studied samples is in a range of 1.57-1.75 eV with a minimum in sample x=0.06 and then *** investigations show that the presence of Co^(2+)/Gd^(3+)cations in an octahedral site of the copper ferrite structure could increase saturation magnetization and coercive field from 567.9 Oe and 23.62 emu/g to 929.4 Oe and 28.27 emu/g,respectively.

关键词： Spinel copper ferrite Citrate-nitrate method Structure phase transition Microstructure properties Magnetic properties Rare earths

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Evaluation of soil loss severity and ecological restoration approach for sustainable agriculture in the Hindu Kush, Karakoram and Himalaya region

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Journal of Mountain Science 2024年第5期21卷 1509-1521页

作者： Arshad ASHRAF Imran ahmad Climate Energy and Water Research InstituteNational Agricultural Research Centre(NARC)Islamabad 44000Pakistan

Soil erosion has resulted in removal of the topsoils containing fine soil particles and plant nutrients, causing decrease in soil fertility in the Hindu Kush, Karakoram and Himalaya(HKH) region. The existing production of cereal crop grains has been reduced to one third of the potential crop grains production owing to land degradation and poor farming practices. It is necessary to assess risk of soil loss and identify appropriate controlling measures to address issues of low agriculture productivity and water insecurity in the region. In the present study, severity of soil loss was predicted using Revised Universal Loss Equation(RUSLE) and ecological measures were identified for sustainable mountain agriculture in the HKH region of Upper Indus Basin, Pakistan. Overall 62.6% area was found to have very low risk of soil loss, i.e., 100 t/(ha·yr) in about 6.8% and 7.4% areas respectively. The mean rate of soil loss was about 41.9 t/(ha·yr) in the Hindu Kush, 31.1 t/(ha·yr) in the Himalayas, 18.8 t/(ha·yr) in the Karakoram and overall 29.7 t/(ha·yr) in the three HKH ranges. As such no considerable measures have been adopted by the communities for restoration of the degraded areas except raising fruit/farm trees and supporting limited social forestry for their livelihoods. The slopes cleared for cultivation and susceptible to erosion may be stabilized through sowing/planting of multi-purpose plant species and formation of proper bench terraces. The conservation of forest ecosystem and pastures at higher elevations would help in reducing overland water flow, risk of flash flood hazard and minimizing sediment loads in the downstream. It is essential to adopt site-specific resource conservation techniques and restore possible ecosystem health for sustainable agriculture and economic developm

关键词： Climate change Erodibility Indus basin Land degradation Slope stabilization

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Federated Learning Security and Privacy-Preserving Algorithm and Experiments Research Under Internet of Things Critical Infrastructure

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Tsinghua Science and Technology 2024年第2期29卷 400-414页

作者： Nasir ahmad Jalali Hongsong Chen Department of Computer Science University of Science and Technology Beijing(USTB)Beijing 100083China

The widespread use of the Internet of Things(IoTs)and the rapid development of artificial intelligence technologies have enabled applications to cross commercial and industrial band *** such systems,all participants related to commercial and industrial systems must communicate and generate ***,due to the small storage capacities of IoT devices,they are required to store and transfer the generated data to third-party entity called“cloud”,which creates one single point to store their ***,as the number of participants increases,the size of generated data also ***,such a centralized mechanism for data collection and exchange between participants is likely to face numerous challenges in terms of security,privacy,and *** address these challenges,Federated Learning(FL)has been proposed as a reasonable decentralizing approach,in which clients no longer need to transfer and store real data in the central ***,they only share updated training models that are trained over their private *** the same time,FL enables clients in distributed systems to share their machine learning models collaboratively without their training data,thus reducing data privacy and security ***,slow model training and the execution of additional unnecessary communication rounds may hinder FL applications from operating properly in a distributed ***,these unnecessary communication rounds make the system vulnerable to security and privacy issues,because irrelevant model updates are sent between clients and ***,in this work,we propose an algorithm for fully homomorphic encryption called Cheon-Kim-Kim-Song(CKKS)to encrypt model parameters for their local information privacy-preserving *** proposed solution uses the impetus term to speed up model convergence during the model training ***,it establishes a secure communication channel between IoT devices and the *** a

关键词： Federated Learning(FL) Internet of Things(IoTs) lightweight Transport Layer Security(iTLS) Cheon-Kim-Kim-Song(CKKS)

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Optimizing calcination of coal by-products for maximizing REE leaching recovery and minimizing Al,Ca,and Fe contamination

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Journal of Rare Earths 2024年第7期42卷 1354-1365,I0006页

作者： Tushar Gupta ahmad Nawab Rick Honaker MP Materials Mountain Pass Mine 67750 Bailey RoadMountain PassCA92366USA Department of Mining Engineering University of KentuckyLexingtonKY40506USA

High-temperature calcination is effective in improving the leaching characteristics of rare earth elements(REEs)from conventional REE-bearing minerals by transforming them into more leachable ***,the recovery of contaminants such as Al,Fe,and Ca also increases *** objective of the study was to maximize the REE extraction while minimizing the concentration of contaminant ions(Al,Ca,and Fe)in the leach *** density fractions of the coarse refuse from the Baker and Fire Clay seam coal refuse were pulverized to a top size of 180μm and used as a feedstock for the *** the samples generated from thermal treatment were leached at 1%(w/v)using 1.2 mol/L sulfuric acid at 75℃ for 2 *** results from a parametric program based on a Box-Behnken design were used for modeling and optimization of three operating parameters associated with the lab-scale calcination *** parameters included temperature(400-800℃),ramp rate(2-10℃/min)and holding time(0-120 min).It was determined that the calcination temperature was the most significant parameter influencing REE *** majority of the heavy rare earth elements(HREEs)were found to be present in an insoluble form in the calcination products and were marginally affected by thermal treatment.A strong correlation between light rare earth elements recovery(LREEs)and Al suggested a possible association with *** optimum operating conditions for high REE recovery with comparatively lower contaminant concentration for 1.6 specific gravity float and 2.2 sink fractions of Baker and Fire Clay seam material were determined to be at 776,800℃ and 407,800℃,calcining temperatures,respectively.A higher optimum temperature of 1.6 float fraction of Baker seam relative to Fire Clay seam material was due to elevated pyrite concentration in Baker seam *** treatment at 400℃ converted pyrite into a soluble intermedium iron oxide,resulting in a high Fe content in the ***

关键词： Calcination Optimization Rare earth elements Coal refuse

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