Latakia University Journal -Basic Sciences Series

Determination of total mercury concentrations in the Auxis rochei fish's spread on the Coast of Latakia city

2025-02-12T08:39:32+00:00

Mercury is one of the most dangerous pollutants that threaten human health and many aquatic ecosystems in many regions around the world, as it moves along the food chain, posing a potential threat to life.

This research focuses on determining total mercury concentrations using atomic absorption technology - cold steam technology in different sizes (small, medium and large) of Auxis rochei fish caught from the shore of the city of Latakia during the spring and summer seasons of 2023.

The results showed higher concentrations of mercury in the summer in the muscles, liver, and gonads, where these concentrations reached (0.267, 4.337, 2.301) compared to the spring season (0.291, 2.51, 2.221), respectively.

It was noted that the values of the target hazard coefficient THQ (Target Hazard Quotients) were less than one in the muscles of fish, as its values ranged from (0.097 - 0.103), and this indicates that there is no health risk when consuming the muscles of this type of fish, while these values were higher than one. In the liver and gonads of these fish, the values ranged between (0.843 - 1.070) and (1.127 - 1.457), respectively.

Energy Level Calculation for a Lithium Metal Film

2025-01-17T00:39:56+00:00

The study analyzes the electronic and thermodynamic properties of thin lithium films using the Green's Function Method, a powerful tool for solving equations of periodic systems. It focuses on the impact of limited size on the quantum properties of thin films, leading to energy level quantization that significantly affects the density of states (DOS) and heat capacity. The research also examines the effect of temperature on thermodynamic behavior, showing a substantial reduction in heat capacity in thin films as thickness decreases.

The tight-binding model is employed to understand electron interactions in materials with periodic potentials, integrating Schrödinger’s equation and Bloch’s theorem to comprehend the electronic band structure. The methodology relies on Fourier transforms and reciprocal lattice analysis to calculate energy levels. The study highlights that thin films with small thicknesses exhibit a strong quantization effect, resulting in significantly spaced energy levels, whereas this effect diminishes with increased thickness.

Practical applications include improving lithium-ion battery efficiency by reducing dendrite growth and enhancing battery stability. These films are also utilized in designing nanotransistors, allowing precise control over energy levels. The results demonstrate that thermal and electronic properties can be greatly optimized by adjusting the film thickness, boosting their applicability in modern energy technologies.

Mathematical and physical differences between curved and flat surfaces in astrophysical observations

2024-09-17T11:31:04+00:00

The study of cosmology is based on Einstein's "general theory of relativity", and this leads to the consideration (to the imaginary) that we live in the middle of a curved space-time. This idea (the idea of space-time curvature) is not easy at all, in other words, it is not easy to represent, and what is being done is a first stage to address and approach some points related to that idea.

There are several difficulties to approach this idea, which is to first imagine four-dimensional space-time and then imagine that space-time is curved. But here we will be concerned with some simple situations: flat space (flat surface) and curved space (curved surface) in two and three dimensions. Any very simple situations and it is only space and not space and time (that is, not space-time) with only two dimensions and not a three-dimensional space where we currently live, the situation would be simpler. So, in other words, we will do what is called "the study of cosmology through the ant or the so-called ant technology", that is, an ant that lives in a two- or three-dimensional space. Here we don't care about time, we only care about space. And we will see what are the points that can be deduced from studying this, that is, what will the ant see when studying it, or in other words, what will we see if we are in the place of the ant?

This is the first way to know that we live in a curved space. This is not easy to do in practical life, especially when studying cosmology, where the distances we are dealing with are very large, on the order of a light-year.

Then the comparison will be made between flat surfaces and curved surfaces; And we will see what is the effect of curvature on the circumference of the circle, and this in turn leads to a physical effect or another physical effect, which is the concept of light flux.

Effect of different preparation methods (dry and wet at 100oC, hydrothermal at different temperatures) on the properties of the textile structure of the mixed oxide group Al2O3 / CdO

2024-09-16T04:06:54+00:00

Samples were prepared from the mixed oxide Al₂O₃/CdO and at a specific molar ratio (Al/Cd 1-0.25 mol) by different methods, (dry ), wet, ( ) hydrothermal, ( ) the value of the surface area of the dry sample reached , for the wet sample , as for the sample prepared by the hydrothermal method at a temperature of 100^oC, the value reached .

The effect of the hydrothermal treatment temperature 70, 100, 130, 150 ^oC on the properties of the tissue structure was studied, and it was found that the surface area increases for the sample treated at 100^oC , and then decreases again, it is equal to the sample treated at 150^oC

Manufacturing of a Selective Electrode Based on a Modified Carbon Paste for Determination of Organophosphate Pesticide Dimethoate in Water Solutions

2024-09-08T04:36:56+00:00

This work focuses on the manufacturing of a simple and rapid selective electrode for determining the organophosphorus pesticide dimethoate, using copper oxide as an electrochemically active material. The copper oxide is mixed with graphite powder and paraffin oil as a plasticizer to achieve the appropriate pasty consistency. A potential study of the mixing ratios between graphite powder, active material, and plasticizer was conducted to determine the optimal ratio. The electrode exhibits a Nernst response within a concentration range of (1×10^-4 to 1×10^-6) mol/L, yielding a Nernst slope of 30.2 ± 2 mV/decade. The effects of the pH value of the medium on the Nernst response of the fabricated electrode as well as the response time were studied, and temperature effects, were studied. The results showed stability of the potential at pH = 4 and a response time ranging from 33 to 60 seconds at temperatures between 20 and 35 °C. The potential selectivity coefficients of the proposed electrode were calculated using the Matched Potential Method (MPM). The results indicated that the proposed electrode demonstrates high selectivity for dimethoate in the presence of various interfering ions. The concentration of dimethoate in some commercial samples was determined using the proposed electrode, yielding recoveries of 102.006% and 104.779%. The results were compared with a reference method, and the Fisher test indicated good agreement between the results of two methods. Therefore, this selective electrode can be adopted as a potential method for the determination of dimethoate pesticide.

Integrating Geochemical Prospecting and Rock-Eval Pyrolysis Data to investigate the Characteristics of Organic Matter from Source Rock from Both the Kermav and Jaddala Formations in the Northern Hussein Block (Aleppo Plateau – Syria).

2024-09-08T04:04:19+00:00

The geochemical characteristics and hydrocarbon generating potential of two source rock formations in the Northern Hussein Block of the Aleppo plateau/Syria; the Kermav formation (Paleocene) and the Jaddala formation (Eocene), were evaluated using the techniques of both prospecting geochemistry (a set of redox-sensitive trace elements signatures) and the Rock-Eval pyrolysis. The organic matter in the Kermav rocks is a type II Kerogen with a very good organic carbon content (TOC) and a very good generating potential, deposited under reduced conditions with fluctuations toward minor oxygen content according to the trace elements signature, indicating a marine depositional environment with varying levels of oxygen deficiency and a marine source of organic matter. In contrast, the TOC of Jaddala formation is lower than that of Kermav, but is good with good generating potential and shows relatively less maturity. It belongs to mixed type II/III kerogen that was deposited under more anoxic conditions with an important contribution of terrestrial organic matter, most likely in a marine depositional environment similar to that of Kermav with dilution of organic matter due to increasing mineral inputs. Both the organic matter and the rock component of the source rocks share a common origin according to trace elements data, that is, they were deposited simultaneously and the organic matter was not post-sedimentary or transported. The Jaddala formation showed signs of hydrocarbon migration from the other rock formations, eventually migrating from the kermav (specifically). Overall, the study provides insights into the geochemical characteristics, paleoenvironmental conditions, and hydrocarbon generation potential of both the kermav and Jaddala formations.

Hydrodistillation and chemical composition of essential oil of leaves of Convolvulus in latakia area

2024-09-01T04:59:02+00:00

The leaves of Convolvulus were collected from Tishreen University in summer 2024. The essential oil of leaves obtaind by hydrodistillation for 4 h utilizing a Clevenger-type

apparatus. Then The essential oil was investigated by GC/MS. The yield of essentiall oil was (0.06%) and eighteen components were characterized most of them from sesquiterpene hydrocarbons, as β-caryophyllene (45.9 %), dodecanal (8.9 %), caryophyllene oxide (4.2 %), tetradecanal (4.5 %) and dihydroedulanI (4.4 %) as the major components.

Assessment of Water Quality of Al-Sain Lake using the Iranian Water Quality Index (〖IRWQI〗_sc)

2024-08-26T09:16:33+00:00

Water Quality Indicators are considered as reliable tools to judge water demand and supply and an important criterion for any monitoring program of the aquatic environment to manage and monitor water to ensure it remains within the required quality limits. This research aims to assess the water quality of Al-Sain Lake, which primarily supplies the city of Latakia and part of Tartous. In this study, we investigated a range of physical and chemical factors of the lake water during the years 2021, 2022, and 2023. Samples were taken from three different monitoring sites following an approved program by those responsible for monitoring and protecting the lake. The Iranian Water Quality Index for Surface Water Resources () was utilized to calculate the water quality, considering indicators such as: pH, ammonium (), nitrate (), phosphate (), turbidity (TUR), electrical conductivity (EC), chemical oxygen demand (COD), dissolved oxygen (DO), total hardness (TH) and fecal coliforms (FC). The study results indicated that the water quality in the lake was within the good category at all designated monitoring points during the years 2021, 2022, and 2023, with a slight improvement in quality in 2021 and 2022 and a slight decrease in 2023 while still remaining within the good classification range.

Chemical study of basaltic rocks at the Tartous patch

2024-08-26T21:07:04+00:00

To achieve the objectives of the study, six rock samples were analyzed using a neutron activation device .The results of the geochemical study of the basalt rocks in the Tartous patch showed that the magma did not show any kind of differentiation on the Harker and MgO diagrams. The samples also fall into the olivine basalt field on the TAS chart. The samples were found to be in the subalkaline, high-aluminium range on the Rogers chart. The AFM diagram showed that the samples in the Tartous area fall into the field of iron thiolite. A gypsum diagram of the local differential showed that the samples were located in the limestone end, which is of the thiolitic type. The geodynamic classification scheme also showed that the volcanism in the Tartous region is a plate volcanism resulting from the partial melting of the upper layer with low melting points, and it is similar to the eastern end of the Ghab collapse and many regions of the world. This confirms that the majority of Pliocene basalt is of the theolitic type.

In conclusion, the characteristics of volcanism in the Tartous patch have been identified as slit-type volcanism, and it has been shown that some of the Pliocene basalt is generally thiolitic (ferro-calcareous), as the basalt rocks in the study area are located in the initial differential phase of the original basalt clays and did not appear to spread along the differential sedimentation trend. When comparing the Tartous basalt with the Safita basalt on the geochemical charts, it was found that there was an almost complete match on all the charts, with some slight differences between them, and this indicates that they were formed from the same cremated chamber during the Pliocene period.

Synthesis and Characterization of Some New Azo Dyes, Azomethine Dye From New Schiff Bases (2-amino fluorene/p- hydroxyacetophenone) And (2-amino fluorene/p- aminoacetophenone)

2024-08-11T05:52:26+00:00

Aseries of Schiff base and their derivative (2-amino fluorene) have been synthesized by para hydroxy acetophenone was condensed with 2-amino fluorene in DMF (dimethyl form amide) in the presence of conc. HCl acid as catalyst to yield the Schiff bases (1). The Schiff’s base (1) was treated with diazotised p-sulphanilic acid to give Azo Dye compound (2), and The Schiff’s base (1) was treated with benzene diazonium salt solution to give Azo Dye compound (3), The Schiff base (4) was prepared by para amino acetophenone was condensed with 2-amino fluorene in DMF (dimethyl formamide) in the presence of conc. HCl acid as catalyst. Then the reaction of Schiff base (4) with 2-hydroxy-5-methyl-1,3-benzene dicarbox aldehyde to give Azomethine Dye compound (5).

The structures of synthesized compounds has been established on the basis of their spectral (FT-IR, Mass,¹H-NMR,¹³C-NMR, elemental analysis) data. TLC confirmed the purity of the compounds.

Calculating Effective Mass in Aluminum Oxide and Studying Current Distribution as a Function of Field and Temperature Using Fowler-Nordheim Function

2024-06-27T07:14:40+00:00

In this study, the effective mass of aluminum oxide (Al₂O₃) and current distribution as a function of electric field and temperature were investigated using the elliptic Fowler-Nordheim function. The research highlights the changes in the effective mass due to environmental factors and the crystal structure. It demonstrates that the effective mass of aluminum oxide differs when it is surrounded by two layers of aluminum compared to when it forms independently. This is attributed to stress effects, surface boundaries, charge distribution, and quantum effects.

The effective mass was calculated by analyzing the curvature of energy levels using the second derivative of energy with respect to the wave vector. Experimental data were employed to plot the relationship between current distribution, electric field, and temperature. The results showed an exponential increase in current with an increase in field and temperature, emphasizing the sensitivity of aluminum oxide to these factors. The graphical representation also demonstrated the relationship between current and temperature variations with correlation equations that elucidate the system dynamics.

These findings are of great significance in microelectronics applications, such as designing insulating layers for semiconductors, solar cells, and optoelectronic systems. The researchers highlighted the potential of leveraging aluminum oxide properties to enhance device performance by controlling the effective mass. The study also emphasized the need for further research to include additional factors such as pressure and impurities to improve result accuracy.

This research forms a foundation for understanding the electronic properties of aluminum oxide and its relationship with environmental factors, paving the way for its use in advanced industrial and technological applications.

Keywords: Effective Mass - Fowler-Nordheim - Al₂O₃ - Current Distribution

Encapsulation of curcumin and diclofenac mixture with sodium alginate and chitosan and evaluation of the encapsulation efficiency

2024-06-26T03:44:48+00:00

Curcumin synergizes with diclofenac to achieve a dose-related anti-inflammatory effect. Curcumin has an activity similar to that of diclofenac, allowing for reduction in side effects. Curcumin inhibits enzymes in the digestive system that destroy diclofenac, which increases the bioavailability of diclofenac, micro capsules of a mixture of curcumin and diclofenac were prepared using polymeric coatings such as sodium alginate with different concentrations and chitosan with specific concentrations in combination with sodium alginate of constant concentration after adding it to a calcium chloride solution.

The encapsulation efficiency when using sodium with a concentration of (3.5%), and calcium chloride with concentration of (2.5%), was 89.5% for curcumin and 98.3% for diclofenac. As for chitosan with sodium alginate at concentrations (0.5 to 3.5) %, the encapsulation rate for curcumin was 85.9% and for diclofenac was 87.5%, as the research results confirm that It is possible to adopt this method in encapsulation of a mixture of curcumin and diclofenac because it is fast, accurate, and has very good encapsulation efficiency.

Developing an analytical method for mercury speciation in natural waters

2024-07-03T04:01:02+00:00

In this research, an analytical method was developed to extract total, organic and inorganic mercury from natural waters by Solid- Phase Extraction using modified and activated silica gel as solid phases, and the concentrations of each were determined using cold vapor technique (Cold Vapor Atomic Absorption Spectrometry: CV-AAS). The silica gel was modified using ammonium pyrrolidine dithiocarbamate (APDC), while the silica gel was activated using chloroform. The extraction process was studied within the range (pH: 2-10), while the recovery process for total, organic and inorganic mercury from the surface of silica gel was studied within the concentration range (1-7 M) for nitric acid. As for method validation, this was done by comparing the results obtained with the results of reference methods. The results showed that the percentage of extraction of inorganic mercury using activated silica gel reached (97.3%) at (pH = 4), while the percentage of extraction of organic mercury using modified silica gel reached (99.3%) at (pH = 3). As for total mercury, it was Its extraction rate is (99.6%) at (pH=3). Regarding recovery, the highest percentage was at the concentration of nitric acid (6 M) for total, organic and inorganic mercury, with pre-concentration factor (100). The capacity of activated silica gel and modified silica gel are (628.44 µg/g), (1022.04 µg/g) respectively. Finally, the method detection limit of the new method was (0.12 ng/l).

The Effect of some Characteristics of Soils Surrounding the Lake of Al-Sin (Baniyas) on the Adsorption of Phosphate Ion

2024-06-23T03:44:19+00:00

يتأثر امتزاز أيون الفوسفات بشكل مباشر بالخصائص الكيميائية للتربة مما يؤثر على سلوك أيون الفوسفات وارتباطه بمكونات التربة. وقد أظهرت دراسة خصائص التربة في منطقة الدراسة أن هذه التربة ذات حموضة معتدلة تميل إلى القلوية قليلاً، وتحتوي على نسبة عالية من كربونات الكالسيوم والمواد العضوية. كما تبين وفقاً لنتائج التصنيف أن هذه الترب تتكون من ترب طينية بنسبة عالية، وترب طينية لومية وترب لومية بنسبة أقل.

أظهرت دراسة الخصائص الامتزازية للترب في منطقة الدراسة أن السعة الامتزازية العظمى (qmax) لأيون الفوسفات في هذه الترب تقع ضمن المجال (239-621 mg/kg.. وبحسب المواقع المدروسة كانت قيم السعة الامتزازية العظمى وفق الترتيب التالي: جيبول< الراهبية< بيت العلوني< القطيلبية< بسطوير< قرفيص< بيت عانا< نبع الواحة. وقد أظهرت دراسة إيزوثيرمات الامتزاز ملاءمة جيدة لنموذج فروندليتش وفقاً لقيم معامل الارتباط (0.87-0.99).

بينت نتائج الدراسة الإحصائية أن السعة الامتزازية العظمى ((qmax، كمؤشر على الامتزاز الأعظمي لأيون الفوسفات، يرتبط مع المتغيرات الآتية: الأس الهيدروجيني pH، وكربونات الكالسيوم CaCO3 وفقاً للقيم الآتية على الترتيب (0.952, .(0.927

Studying the effect of paint on the absorption of some zinc alloys for light rays

2024-07-27T04:21:27+00:00

In this research we have studied the effect of paint on the absorption of some zinc alloys for light rays.and that for certain superficial density for the paint we have used. These painted alloys can be used as thermal sensors in the devices that measuring the intensity of solar radiation. To complete the study, we calculated the thermal energy absorbed by these painted samples when exposed to direct solar radiation. The total direct solar radiation energy can be calculated using the regulatory laws and some computer programs. This study was conducted in the city of Jableh, which is located at sea level.

And in this research we have studied the relationship between the absorption and atomic number of these alloys, and the relationship between the absorption and the percentage of zinc in these alloys we have used. this research showed that the absorbed energy by these painted metals increase with the atomic number of these alloys ,and it also increase with the percentage of zinc in these alloys.

ZnxCoyO4 spinel's synthesis and electrical characteristics investigated at various frequencies

2024-10-10T09:26:32+00:00

Zn_xCo_yO₄ spinel samples were made using the thermal ceramic method, with (x = 0.2, 0.4, 0.6, and 0.8) as the molar ratios for samples. The molecular weights of the main compounds were used to determine the necessary weights of each material. The samples were sintered for 30 hours at 450^oC after the doping and heating processes were completed at the selected molar ratios and within the temperature range of 25–450^oC. Within the frequency range of 5Hz-1MHz, the electrical parameters of the resultant samples were diagnosed and quantified. These properties included electrical conductivity σ, electrical capacitance C, relative dielectric constant Ԑ_r, and loss tangent tanδ. The findings demonstrated that, with respect to the variation in the percentage of zinc (Zn) in the samples, the highest electrical conductivity value is 5.50×10⁺⁴ (Ω.cm)^-1, the highest value of C is 84.57 pF, the highest Ԑ_r value is 190.58, and the lowest value of tanδ is 2.34×10⁺⁶.

A Comprehensive Geochemical Study of Al-Debaneh Source Rock in Al-Mhash Block, Central Euphrates Depression, Syria

2024-06-02T02:57:39+00:00

This study presents a geochemical analysis of the Debaneh formation in the Al-Mhash block located in the Central Euphrates depression of Syria. The primary objective of this research was to assess the organic matter within the rock formation, focusing on its origin, composition, maturation, and its Total Organic Carbon content. Specifically through unconventional geochemical parameters, which has not been previously done. The organic matter was extracted for analysis. Trace elements (V, Cr, Co, Ni, Sr) were meticulously examined and compared in terms of their distribution patterns and content between both the rock and the organic matter. In Addition, the organic carbon content was estimated, and various elemental ratios such as V/V+Ni, Ni/Co, H/C, and TOC were studied. The results suggest that both the rock and the organic matter share a common origin and were deposited at the same time. In addition, it is noted that the organic matter is of terrestrial origin (terrestrial plant debris input dominance) with a level of maturation is relatively not very well developed. It should be noted that the methodology used in this study differs from traditional methods as it incorporates (mainly) inorganic geochemistry in many aspects to address a topic that has historically been addressed only by organic geochemistry (biomarkers, etc.). This innovative technology is relatively new in the region and represents pioneering work in this field.

Study the effect of temperature and shear stresses on flow behavior Polylactic acid – polybutene-1 (PLA/PB-1) molten mixture

2024-06-02T02:34:04+00:00

In this research, we have studied the rheological properties of samples of PLA / PB-1 mixtures under the influence of high shear stress and different temperatures, where mixture were prepared in proportion 70/ 30 The mixture was prepared in preparation for the tests in the viscometer Then study the viscous properties by determining the viscosity and viscous activation energy (E) at constant shear stress, constant shear rate and through Newton's index (n).

The real viscosity transformations were also studied in terms of the inverse of temperature to determine the activation energy at constant shear stresses and constant shear speed, as the activation energy is useful in determining the sensitivity of the polymer's viscosity to temperature change.

The elastic properties of the studied mixtures were also studied using Barus technology, and it was found that the rate of swelling increases with the increase in shear stress, and it was found that there is no significant effect on the swelling coefficient B.

Synthesis of compound has the total Chemical formula C15H12PSNO3 and determination of some of its physical properties and extraction capacity of ions Znic (II) and magnesium (II) ions from their aqueous media

2024-06-02T02:48:25+00:00

The O,O-(Di)(8-quinolines)Thiophosphric acid was formulated with the chemical formula C₁₈H₁₃PSN₂O₃ to be used as a solvent extract of Znic (II) and magnesium (II) ions from their aqueous media.

The identification of the compound was determined using IR and NMR spectroscopy and some physical properties (melting point, color and appearance) were determined. The ratio of some elements in the prepared compound: sulfur, phosphorus and carbon was determined according to the methods mentioned in the international references UOP and ASTM and Some factors influencing the extraction process, such as stirring time, were investigated to achieve the equilibrium and concentration associated with the organic phase, the pH effect and the ratio of the aqueous phase to organic phase. The percentage of extraction were also calculated.

Chemical Content Analysis of Syrian Fig Latex Extracts

2024-07-14T03:58:49+00:00

Samples of fig tree fruit latex were extracted with n- hexane, methanol, dichloromethane and then the contents of the extract were determined using technology of GC/MS.

The percentage of extracted substances is 10%, 11.4%, 8.2% of the weight of the studied latex. 23, 21, 16 compounds were identified in the extracts. These compounds constitute 99.9%, 97%, 100% of the n- hexane, methanol, dichloromethane extracts respectively.

It was also noted that the most important compounds found in the extracts of fig fruit latex are:

n- hexane extract: Lupeol acetate 52.3%, Cycloeucalenol acetate 16.8%, β-Amyrin 8.9%, Lupeol 5.6%, Cycloartenol acetate 5.2%.

methanol extract: Betulin 32.7%, 28-(Acetyloxy)urs-20(30)-en-3-yl acetate 25.2 %, Lanosta-8,24-diene-3,22-diol-diacetate (3β,22R) 22.6 %, Oxolinic acid 10.2 %.

dichloromethane extract: Betulin.45.7%, Lanosta-8,24-diene-3,22-diol-diacetate (3β,22R) 24.2 %, Oxolinic acid 10.5 %, Lupa-13(18),22-dien-3-ol- acetate 9.9%.

Quantum-Mechanic Investigation of the Nickel-Catalyzed [3+2+2] Cocyclization of Ethyl Cyclopropylideneacetate with two Alkynes

2024-08-26T20:57:36+00:00

The mechanism of the Ni(0)-catalyzed [3+2+2] cyclization of cyclopropyl-ideneacetate with two alkynes was investigated using the M06-2X function with two base sets def2-SVP for the main elements and def2-TSVP for the nickel atom. Only the pathway leading to the formation of 3,4- or 3,5-disubstituted products via [3+2] cocyclization was studied, with the previously proposed mechanism being reconsidered to include the return of the ligand in the final step after its removal in the initial step of the reaction. Previous studies indicate that the 2,5-disubstituted products can be formed preferentially via nickelacyclopentadienes generated by [2 + 2] cocyclization when using strongly electron-deficient alkenes. Our computational results indicate that electron-rich substituted alkenes (such as HCCSiMe3) or bulky (such as HC CtBu) lead to the formation of 3,5-disubstituted products, and the former is more active than the latter, which requires a lower activation energy of about 3.2 kcal/mol. While less-congested or simple substituted alkenes (such as HC CMe3 or (HC CPh) lead to the formation of 3,4-disubstituted products, and the former is more active than the latter ((E# = 2.6 kcal/mol). Our theoretical results agree with previous theoretical and experimental studies.

Estimates for Fekete-Szegö Inequalitie in New Subclasses of Bi-Univalent Functions Defined by Subordinate and Integration Operators

2024-05-09T03:13:23+00:00

In this research, we present an estimate of the Fekete-Szegö inequality and the Hankel determinant of second order in some bi-univalent functions classes after we were able to use the Komatu integral operator and the exponential function, as well as the principle of dependency in setting definitions for two new classes of bi-univalent functions classes, where an estimate was found for the initial coefficients in previous studies.

Preparation of Magnesium Sulfate salt MgSO4 from Seawater

2024-09-05T04:36:33+00:00

In this research, magnesium sulphate salt was prepared from seawater in a new, economically feasible method. The method relied on direct precipitation of magnesium hydroxide using sodium hydroxide and subsequent treatment with concentrated sulfuric acid only to obtain magnesium sulphate, in addition to the traditional method based on precipitation with ethanol.

Marine water samples were collected from several areas along the coast of Latakia city ( estuary of the Northern Kabir River, Higher Institute for Marine Research, Sports City) during the summer of 2023.

The results showed that the average amount of magnesium sulphate salt produced according to the traditional method (precipitation with ethanol) was: 3.82 g/L, 3.27, and 2.13 in the research areas, the sports city, and the mouth, respectively, while the average amounts of salt produced according to the new method were as follows: 7.91 g\L, 6.65, 4.56 in the previous regions, respectively. Several tests were also carried out to study some of the physical properties of the resulting magnesium sulphate salt (solubility, melting point) and compare them with reference values. The results showed that these properties were identical.

The identification and detection of curcumin and its constituent compounds using high-performance liquid chromatography (HPLC) technology, and determination of the optimal conditions for the developed analytical method

2024-05-19T05:03:52+00:00

This study aimed to develop a sensitive and accurate analytical method to determine and

detect curcumin using high-performance liquid chromatography HPLC. Optimal conditions such as mobile phase, temperature, flow speed, and the maximum wavelength for analysis λ_max were studied. The study was carried out on a standard solution of curcumin with a concentration of (40ppm) and a separation column (C₁₈) was used with specifications (250 ×4.6m.m.5μm).

The results showed the optimal conditions were as follows: the flow speed of the mobile

phase was (0.8 ml/min) as a mixture of acetonitrile and phosphoric acid (0.1%) in a ratio of (40:60 v/v), the temperature of the separation column was (40 ̊C), while λmax was (425nm).

Curcumin showed three peaks with average area (X₁=87279, X₂=881260, X₃=7641952),

at average retention time (T₁=6.31, T₂=6.87, T₃=7.50) min with relative standard deviation (RSD%) (0.83, 0.08, 0.01) respectively, the sum of the average areas of the peaks was (X_t=8610491).

The calibration curve for curcumin and its three compounds was characterized by good

linearity within a range of concentrations ranging from (0.001-40)ppm. The recoverability R% was calculated and was (99.66%). The limit of quantitative detection LOQ was (0.056 ppb), and the qualitative limit of detection LOD was (0.009 ppb). The results confirm the possibility of adopting this method to determine curcumin and its various compounds.

Study of the total concentration and morphological distribution of some heavy metal elements in benthic sediments within some open and closed ecosystems

2024-05-19T04:57:16+00:00

In this research, the total concentration and morphological distribution of elements (Hg, Pb & Cd) in bottom sediments were determined within two study sites, the first site was Lake 16 Tishreen Dam and the second was the mouth of the Al-Kabir Al-Shamali River. The values of the total concentrations of the studied elements ranged as follows: Hg(1.58-0.25), Pb(28.45-6.22), Cd(5.69-0.85) (mg/kg). The highest values of these elements were recorded during the summer at the downstream site, while the lowest values were recorded. Values for concentrations during the winter at the dam site. As for the results of sequential extraction, the following values were recorded: the element lead was present in the highest percentage in the residual form (59.18%), while the percentage of its presence in the recoverable form recorded the lowest value (9.15%). As for the element cadmium, it was present in the highest percentage in the extractable form (43.56%) While the percentage of the traceable form was the lowest (15.24%), and finally, mercury concentrations recorded the highest values within the extractable form (55.35%), while the lowest percentage was within the residual form (4.87%).