Gas Chromatography And Mass Spectrometer Research Articles

Assessment of artificial intelligence to detect gasoline in fire debris using HS-SPME-GC/MS and transfer learning.

Due to the complex nature of the chemical compositions of ignitable liquids (IL) and the interferences from fire debris matrices, interpreting chromatographic data poses challenges to analysts. In this work, artificial intelligence (AI) was developed by transfer learning in a convolutional neural network (CNN), GoogLeNet. The image classification AI was fine-tuned to create intelligent classification systems to discriminate samples containing gasoline residues from burned substrates. All ground truth samples were analyzed by headspace solid-phase microextraction (HS-SPME) coupled with a gas chromatograph and mass spectrometer (GC/MS). The HS-SPME-GC/MS data were transformed into three types of image presentations, that is, heatmaps, extracted ion heatmaps, and total ion chromatograms. The abundance and mass-to-charge ratios of each scan were converted into image patterns that are characteristic of the chemical profiles of gasoline. The transfer learning data were labeled as "gasoline present" and "gasoline absent" classes. The assessment results demonstrated that all AI models achieved 100 ± 0% accuracy in identifying neat gasoline. When the models were assessed using the spiked samples, the AI model developed using the extracted ion heatmap obtained the highest accuracy rate (95.9 ± 0.4%), which was greater than those obtained by other machine learning models, ranging from 17.3 ± 0.7% to 78.7 ± 0.7%. The proposed work demonstrated that the heatmaps created from GC/MS data can represent chemical features from the samples. Additionally, the pretrained CNN models are readily available in the transfer learning workflow to develop AI for GC/MS data interpretation in fire debris analysis.

Emission of Volatile Organic Compounds from the Heat Treatment of Afrormosia and Newtonia Wood: Effects of Air and Palm Oil Heat Media

The objective of this work was to study the influence of palm oil on the VOCs emitted during the heat treatment of Afromosia (Pericopsis Elata Van Meeuwen) and Newtonia (Newtonia paucijuga Harms) wood by comparing to the VOCs emitted during the heat treatment under air. Two batches of Afrormosia and Newtonia wood samples were heated under air and palm oil at temperatures of 160 °C, 180 °C, and 200 °C for 2 h. Then, the VOCs were collected by Solid Phase Micro Extraction (SPME) and measured using a Gas Chromatograph and Mass Spectrometer (GC-MS). The results showed that the temperature, the wood species, and the treatment medium have a great influence on the categories and percentages of VOCs emitted. In the air heat treatment, ethers were the most emitted VOCs from Afrormosia and Newtonia when these woods were thermally treated at 160 °C. Newtonia treated under air at 180 °C emitted more esters, while Afrormosia continued to emit more ethers under the same conditions. Moreover, Afrormosia and Newtonia treated at 200 °C emitted more ketones and aldehydes, respectively. Regarding the heat treatment of Afrormosia and Newtonia wood under palm oil, a similarity of the VOCs emitted from Newtonia with those emitted from Afrormosia under the same conditions was observed. Furthermore, palm oil was the main factor conditioning the nature of the VOCs emitted during the heat treatment. In general, for the treatment of Afrormoshia wood with palm oil, the VOCs emitted, such as alcohols, alkanes, and ethers, decreased with the treatment temperature. Ethers and ketones increased with the processing temperature. At 160 °C and 180 °C, the percentage of aldehydes was highest, while, at 200 °C, the percentage of esters was highest. Similarly, for Newtonia treated under palm oil, adehydes, ethers, and alcohols were the most abundant VOCs emitted at 160 °C. However, their percentages decreased with the increase in the treatment temperature; on the contrary, esters and ketones were weakly emitted at 160 °C and became abundant with the increase in temperature. Additionally, the ethers formed during the heat treatment of Afrormosia and Newtonia wood treated under air carry acetyl groups, while those formed during the treatment of the said wood under palm oil carry hydroxyl groups.

Production of liquid hydrocarbons by thermo-acidic method from waste high-density polyethylene.

The study explains the production of useful liquid hydrocarbons by thermo-acidic catalytic thermal degradation of waste high-density polyethylene. A comparative study of the liquid samples with or without catalysts. Energy demand is high in the world. Waste plastic conversion is nowadays a concern of interest research for scientists. HDPE (High-density polyethylene) is the most common plastic used in households. Different types of catalysts and techniques have been used in the alteration process of waste HDPE. This paper deals with the kandite group of catalyst kaolin and the montmorillonite group of catalyst sodium bentonite in acid-activated mutated form. This paper aims to explore the prominent utilization of kaolin clay and sodium bentonite clay minerals as a catalyst for the alteration of waste HDPE into fuel resources and to develop a cost-effective recycling experimental set-up for plastic waste conversion. Thermo-catalytic acid activation has been done for clay mutation. Hydrochloric acid-activated catalysts have been used in this study. FT-IR (Fourier Transform Infrared Spectroscopy) and GC-MS (Gas Chromatography and Mass Spectrometer) techniques have been used to explore the prominent compounds in the product samples. Maximum energy per photon for RO (Parent Oil/Raw Oil) and AO(Acid treated thermo-catalytic oil) samples are respectively 58034.01×1024 Joules and 59271.40×1024 Joules concerning wave numbers 2921.42 and 2983.71 cm-1. Compounds of functional groups C-CH3, CH2, alkenes, and CH3 have been identified for RO and AO samples. Less gaseous hydrocarbons 31.79% (outcomes) or 29.66 % (production yield) and 150.06 % of increment in wax have been calculated after using acid-treated catalysts. Aliphatic compounds like alkanes and alkenes are present in the samples. A mixture of acid-treated kaolin and acid-treated sodium bentonite as the catalysts for degrading waste HDPE into liquid oil greatly reduces wax formation. Average outcomes and production of liquid hydrocarbons are good results with the acid-treated catalytic degradation of HDPE waste. One remarkable fact is that the yield percentage of liquid products is higher in acid-activated catalytic thermal degradation.

Conversion of Mixed Waste Plastic into Fuel Oil Production from Pyrolysis

Pyrolysis is the thermochemical decomposition of organic materials at high temperatures in the absence of oxygen. The process usually takes place in a sealed vessel under high pressure. Pyrolysis involves the simultaneous change of chemical composition and physical phase and irreversible. Excessive pyrolysis which leaves most of the carbon as a residue is called carbonization. Pyrolysis can deal with a variety of organic materials including plastic waste, food waste, crop waste, used cooking oil, used engine oil, etc. Pyrolysis is used to transform a variety of household items and industrial residues into fuel by recovering them. During pyrolysis, the molecules of the object vibrate at high frequencies to the extent that the molecules break down. The rate of pyrolysis also increases with the increase of temperature. The temperature of household items ranges from 370°C to above 410°C. Industrial applications have temperatures above 430°C. Pyrolysis is the transformation of waste biomass into a liquid fuel form. The density of the product fuel is 0.89gram/millilitre. The fuel produced has a long carbon chain length C9-C24 which is determined by Gas Chromatography and Mass Spectrometer (GC/MS). The produced fuel functional group and energy fuel heat enthalpy value is shown in the Fourier Transform Infrared Spectroscopy (FTIR) analysis result. The fuel produced can also be used as an internal combustion engine. The feed stock can be used as feed for refineries or as power generation feed for power plants. The objective of this research is to address the problem of waste plastic by using economical technology pyrolysis for waste reduction and energy recovery. Along with these environmental problems can also be solved. With the help of economical technology, we can save the environment and the problem of inflation of petrol in our country can also be reduced to some extent.

Temperature dependency of VOCs release characteristics of asphalt materials under varying test conditions

Asphalt pavement is increasingly used in paving and roofing. However, the release of volatile organic compounds (VOCs) from asphalt harm both the environment and humans. Various methods were applied to characterize the VOCs for better understanding and inhibiting. However, asphalt VOCs have huge heating temperature dependency, which makes the asphalt VOCs' characterization complicated. In this research, three kinds of heating conditions, thermal gravimetric (TG) analyzer, pyrolysis (PY) analyzer, and thermal desorber (TD), were compared to determine the temperature dependency of VOC release characteristics. Gas chromatography and mass spectrometer (GC-MS) were then coupled for VOC detection. Results indicated that the TG heating condition can surely simulate the volatilization of VOCs from some asphalt that is not in contact with air (no oxygen) during the actual construction process, while PY and TD represent the substances released by the asphalt due to the boiling point at a certain temperature and under the actual construction process, respectively. The components detected by TG heating condition are both large and small molecules, while PY and TD heating condition will detect large molecules or small molecules, respectively. The VOC composition results under various heating conditions reflect the chemical reaction law of asphalt molecules in the heating process. When heating asphalt binders to a higher temperature, macromolecular substances will gradually crack and oxidize into small molecular substances, sulfides and nitrides. With the increase of temperature, the change trend of VOC components under different conditions is different.

Gas mixture quality monitoring for the RPC detectors at the LHC experiments

Resistive Plate Chamber (RPC) detectors are widely employed in the muon trigger systems of three experiments at the CERN Large Hadron Collider (LHC) thanks to their excellent time resolution. The LHC RPC systems are operated under gas recirculation to reduce operation cost and greenhouse gas emissions since their gas mixture is based on C2H2F4, which has a global warning potential of 1430 and it is subject to the European F-gas Regulation. Extensive gas analysis campaigns have been performed during LHC Run 2 for the CMS RPC and ALICE Muon Trigger (MTR) systems to verify the gas mixture quality and possible accumulation of impurities. A particular attention has been addressed to the ALICE MTR system, which has been operated under gas recirculation from the end of 2015. In order to validate the system ensuring good detector operation, the gas recirculation has been increased in steps: 30%, 60% and 70%. Detector currents and gas mixture quality have been closely monitored. A gas chromatograph and mass spectrometer (GC/MS) station has been installed to analyze the MTR gas mixture in different points of the gas system: fresh gas from the mixer, detectors output and output of the purifier module. Several impurities have been found and identified. Most of the impurities are created inside the detector gas gap due to the fragmentation of the C2H2F4 molecule under the effects of electric field and radiation. The GC/MS analyses have been regularly performed in 2016 and 2017. It has been demonstrated that impurities concentration (at the level of tens of ppm) increases with the increase of the gas recirculation fraction. GC/MS analyses have been also performed after the purifier module showing that some impurities are filtered while others not. In parallel, the RPC currents have been constantly monitored, and their trend showed no correlation with the gas recirculation fraction. In 2017 an Ion Selective Electrode station was installed to measure the fluoride ions (F−) concentration in the MTR RPC gas mixture. Indeed the products of the C2H2F4 fragmentation not always recombine and F^− species can stay free in the gas mixture. The analyses show that F− are present in the mixture exiting the RPCs and their concentration increases with the increase of luminosity, even if it stays at the level of ppb per day. A comprehensive overview of the results obtained from the different types of gas analyses and possible correlation with RPC currents and LHC luminosity will be presented.

Biodiesel Production From Sardine Flour Used Cooking Oil Using One Step Transesterification Techniques

Diesel oil demand as energy source at industrial, transportation and electric generating sector are increasing and it resulted with the decreasing of fossil energy source backup. Biodiesel as an alternative energy source to substitute diesel oil can be utilized from used fried oil of sardine flour. The purpose of this research was to develop the technology to convert used fried oil of sardine flour to become biodiesel using one step trans-esterification technic as an alternative of renewable energy source and also to utilize waste of used oil. Biodiesel made using one step trans-esterification technic with NaOH catalyst concentration 0.5; 1.0; 1.5; 2.0 (% m/m) from total weight of oil and methanol. Trans-esterification process run for 30, 60 and 90 minutes at 65 temperature. The biodiesel obtained was analyzed using gas chromatography and mass spectrometer (GC-MS). The quality was determined by comparing its physicochemical properties and compared to the SNI standard 04-7182-2015. The result of GC-MS showed 10 peaks corresponding to ten methyl ester (biodiesel): octanoic acid methyl ester; decanoic acid methyl ester; dodecanoic methyl ester; tridecanoic acid, 12-methyl-, methyl ester; pentadecanoic acid methyl ester; hexadecatrienoic acid methyl ester, 9-hexadecenoic acid methyl ester, 9-hexadecenoic acid methyl ester, trans-13-octadecenoic acid methyl ester, hexadecanoic acid methyl ester. The biodiesel obtained has a density of 908 kg/m3, viscosity of 3.13 mm2/s, acid value of 0.29 mg-KOH/g found in treatment 1.5% NaOH and time process of 60 minutes. Viscosity and acid value were in a good agreement with SNI standard 04-7182-2015. The research shows that used fried oil of sardine flour has possibility as biodiesel source.
 Keywords: Biodiesel; sardine flour used cooking oil; trans-esterification

Study of antibacterial activity of Tamarindus indica Linn seed oil and its fatty acids

The study of antibacterial activity of oil from Tamarindus indica Linn seed and fatty acids was conducted in this research. Oil of this plant seed was isolated by extraction and fractionation. Constituents of fatty acid in the oil identified as methyl ester fatty acids. The methyl ester fatty acid was carried out by trans-esterification with methanol/BF3. The methyl ester was identified by gas chromatography and mass spectrometer (GC-MS). There are 13 fatty acids in the Tamarindus indica seed oil including octanoic, decanoic, dodecanoic, tetradecanoic, hexadecanoic, octadecanoic, eicosanoic, docosanoic, tetracosanoic, 11-octadecenoic, 11-eicosenoic, 9,12-octadecadienoic, and 9-octadecenoic acids. The transformation of tamarind seed oil into fatty acids was carried out through hydrolysis with potassium hydroxide solution followed by acidification with a hydrochloric acid solution. The physical and biological properties of the seed oil and fatty acids against antibacterial activity are reported in this paper.

A Highly Sensitive Real-time Immuno-PCR Assay for Detecting Benzo[a]pyrene in Food Samples by Application of Biotin-Streptavidin System

Benzo[a]pyrene (BaP), a kind of polycyclic aromatic hydrocarbon, has great potential hazards to the ecosystem and human health. In this study, based on the preparation of BaP immunogen and coating antigen, a specific polyclonal antibody targeting BaP was generated, and a highly sensitive real-time immuno-PCR assay using the biotin-streptavidin system (BA-IPCR) was developed for detecting BaP in vegetables and barbecue food. Several detection conditions were optimized, such as blocking reagent, the concentration of streptavidin, and the concentration of biotinylated DNA (bio-DNA). Under the optimal conditions, a calibration curve was constructed in the concentration range of 5 pg L−1 to 10 ng L−1. The limit of detection was 2.85 pg L−1. Recovery of the spiked samples ranged from 92.1 to 109.6%. This immunoassay showed high specificity, with low cross-reactivity values with BaP analogues. The consistency between the results obtained from BA-IPCR and gas chromatography and mass spectrometer (GC-MS) was 98.96%. This proposed method is reliable and has great potential to detect trace BaP in environmental and food samples.

Crude Oil Contaminated Water Treatment: Development of Water Filter from Locally Sourced Materials

This study aimed at developing a simple and cheap water filter bed using locally sourced materials such as maize cobs, sand, and charcoal. The filter performance was assessed by analyzing water pH, turbidity, TDS, and nitrate content using computer Vernier probes. Total hydrocarbon contents, and heavy metals analysis were also done using Gas Chromatography and Mass Spectrometer (GC-MS) and Atomic Absorption Spectroscope (AAS), respectively. The obtained results showed a high filter capability of removing heavy metal contaminants in water. A percentage removal of 44%, 25%, 51%, and 88.5% of cadmium, copper, cobalt and zinc, respectively, was recorded. The filter showed a high capability in removing organic contaminants and also reducing turbidity, TDS and nitrate content. It was also able to treat contaminated water from a pH of 5.25 to 7.33 approximately.

Combustion properties and toxicity analysis of coal gasification tar residue

Coal gasification tar residue (CGTR) is a kind of solid waste from coal gasification, especially in fixed-bed technology. With high fixed carbon and caloric value, it can be used as an organic feedstock and/or fuel. The combustion properties of CGTR before and after extracted by ethyl acetate were investigated. The toxicity of extract and emissions during combustion was analyzed by gas chromatography (GC) and gas chromatography and mass spectrometer (GC-MS). Experiments show that CGTR can volatilize toxic matter such as alkyl-substituted phenols, amides, and polycyclic aromatic hydrocarbons (PAHs), etc., during pyrolysis at temperature below 400 °C. After CGTR was extracted with ethyl acetate, the separated solid residues were more stable and environmentally friendly than CGTR if used as fuel. Very few toxic emissions are from the residue extracted from CGTR at temperature below 400 °C. Much heat can release when the extracted residue combusts from 400 °C to 700 °C.

The Antibacterial Activity of Satureja khuzestanica Essential Oil Against Clinical Isolates of E. coli

Background: In folk medicine, Satureja khuzestanica infusion is prescribed to use before the meals to treat muscle pains, indigestion, cramps, nausea, diarrhea, and infectious diseases, especially bladder infections and inflammations. Objectives: This study aimed to evaluate the antibacterial activity of S. khuzestanica essential oil against clinical isolates of E. coli from urinary tract infections. Materials and Methods: The chemical composition of S. khuzestanica essential oil was determined by gas chromatography (GC) and mass spectrometer (GC-MS) analyses. The antibacterial activity of S. khuzestanica essential oil and carvacrol as its main component was evaluated by disk diffusion and microbroth dilution assays. Then, the synergistic activity of essential oil and carvacrol with gentamicin were determined by checkerboard microtiter assay. Results: The chemical analysis of S. khuzestanica essential oil revealed the presence of carvacrol (94.1%) as its main component. The inhibition zone diameters of S. khuzestanica essential oil and carvacrol dose-dependently increased. The Minimum Inhibitory Concentration (MIC) values of S. khuzestanica essential oil and carvacrol were 0.14 ± 0.08 µL/mL and 0.09 ± 0.04 µL/mL, respectively. S. khuzestanica essential oil and carvacrol showed bactericidal effects against clinical isolates of E. coli and synergistic effect with gentamicin (fractional inhibitory concentration index < 0.05). Conclusions: The antibacterial activity of S. khuzestanica essential oil is associated with carvacrol as its main component. The presence of other minor components in essential oil decreases the antibacterial activity of S. khuzestanica essential oil. Other clinical studies are essential to demonstrate the antibacterial effects of S. khuzestanica for treatment of urinary tract infection.

Antifungal activities of essential oils from some Iranian medicinal plants against various post harvest moulds

The potential antifungal effects of the essential oils and components of Thymus vulgaris L.,Thymus migricus Klokov and Desj-Shost., Thymus koschyanus Boiss., Mentha spicata L.,Mentha pulegium L., and Satureja mutica Fisch and C.A. (Lamiaceae) were investigated against four food poisoning and plant pathogens. The essential oils were obtained by hydro distillation of dried plant materials and their composition was determined by gas chromatograph and mass spectrometer (GC-MS) in previous studies. The minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) of the oils and their components were determined by dilution assays. Thymus species showed very strong antifungal activities. Culture Potato Dextrose Agar (PDA) media with all oil-enrichment resulted in significant (P≤0.01) reduction on subsequent colony development of Rhizopus oryzae (up to 28%) at 100 ppm; Botrytis cinerea (up to 100%); Penicillium expansum (up to 69%) at 100 ppm and Rhizopus stolonifer (up to 56%) at 100 ppm. Among studied fungi, B. cinerea and P. expansum were the most sensitive pathogens treated with MICs of 100 and 150 ppm, respectively. Differences between high MICs and MFCs of M. spicata and T. vulgaris and low MICs and MFCs of T. koschyanus and T. migricus inhibiting the growth and colony development of tested fungi correlated with simultaneous high concentration of thymol and carvacrol in species of T. koschyanus, T. migricus, M. pulegium and S. mutica. It is concluded that essential oils of Thymus, Satureja and Mentha species possess great antifungal potential and could be used as natural preservatives and fungicides. Key words: Antifungal activity, plant pathogens, essential oils, fungal growth, Lamiaceae family.

Effects of Sediment Characteristics and Location on Polycyclic Aromatic Hydrocarbon (PAH) Associations

Polycyclic aromatic hydrocarbons (PAHs) distribution on aquatic particle sizes determines their transportation and degradation fate and hence their management performance for aquatic environment. Using thermal desorption (TD) extraction coupled to gas chromatography and mass spectrometer (GC-MS), we investigated PAH concentration variation in size-fractionated urban creek surface sediments. Sediment fractions were also investigated for their major material composition and chemical oxygen demand (COD). In general, the PAH’s concentrations and volatile content by particle sizes indicated bimodal distributions with smaller and larger particles enriched with constituents than with the intermediate sized sediment particles. However, most mass of the PAHs was associated with the smaller and intermediate-sized sediments. For smaller sediments, sediments affected by commercial area runoff showed higher concentrations of PAHs than that of non-commercial area runoff sediments. Linear correlations between sediment COD and PAH concentrations were obvious for highly volatile sediments than that of less volatile sediments.

Production of Valuable Heavy Hydrocarbon Fuel Oil by Thermal Degradation Process of Post-Consumer Municipal Polystyrene (PS) Waste Plastic in Steel Reactor

Heavy hydrocarbon fuel oil production was conducted only Polystyrene (PS) waste plastic and temperature range was used for this experiment 200- 450 ℃ and thermal degradation process utilized. Fractional column temperature range was used for heavy fuel oil collection 340-365 ℃. Polystyrene waste plastic was used only this experiment and experiment was performed without catalyst in the batch process under laboratory fume hood. Produced fuel was analysis by Gas Chromatography and Mass Spectrometer (GC/MS) and FT-IR. GC/MS analysis result indicates that produced fuel hydrocarbon chian range C6 to C25 and FT-IR analysis result provided produced fuel functional group band energy which is reflect with calorific value. It was stated that proper selection of the process parameter and make it possible to control and limited grade fuels production product distribution such as valuable hydrocarbon fuel oil and other grade fuels fraction. Basic analysis of heavy hydrocarbon fuel oil GC/MS and FT-IR results described in the result and discussion section. Produced fuel sulphur was determined by ASTM test method and sulphur content was less then environmental protection agency (EPA) level. Fuel could be used for feed stock refinery or heavy equipment because produce fuel has hydrocarbon range is C6 to C25.

COMPOSITION OF HYDROCARBON TYPE FUELS FORMED IN THERMAL DECOMPOSITION OF MUNICIPAL SOLID WASTE PLASTICS AND CALCIUM CARBONATE

Random mixtures of waste plastics raw materials were thermolysed into liquid hydrocarbons at laboratory scales in a batch process by using a stainless steel reactor. Two series of experiments were carried out with random mixtures of waste plastics such as low and high density polyethylene, polypropylene, and polystyrene in the presence of 10 and 20 % calcium carbonate, respectively, at temperatures between 100 and 430 oC. Four types of randomly mixed waste plastics were used in each series of experiments. The hydrocarbon oils formed were analyzed by using a gas chromatography and mass spectrometer (GC/MS) to determine the amounts and types of hydrocarbons. By using 10% calcium carbonate, the formed hydrocarbon mixture contained C 4 to C 40 compounds while, in the presence of 20% calcium carbonate, the product consists of C 3 to C 27 hydrocarbons determined by GC/MS analysis. Due to the high number of hydrocarbons in the oils formed in each series of thermal decomposition experiment, the oily products can be used as fuels for internal combustion engines or electric power plants.

Chemical composition and antifungal, phytotoxic, brine shrimp cytotoxicity, insecticidal and antibacterial activities of the essential oils of Acacia modesta

Many bioactive compounds are produced by the medicinal plants that have important pharmacological activities. The present study describes the chemical composition, antifungal, phytotoxic, brine shrimp cytotoxic, insecticidal and antibacterial activities of essential oils from Acacia modesta. The oils were extracted from the n-hexane fraction of the aerial parts of the plant and were analyzed by gas chromatograph and mass spectrometer (GC-MS). The results revealed 38 components from the oil of A. modesta. The oils exhibited moderate antifungal activity (40%) against Microsporum canis and low against Fusarium solani (25%). At the concentration of 1000 and 100 µg/ml, the oils showed moderate phytotoxic activity of 50 and 40%, respectively, against Lemna minor. The oils were highly cytotoxic at the concentration of 100 µg/ml killing all the shrimps in the experiment. At the concentration of 10 µg/ml only 2 and at concentration of 1 µg/ml, only 8 shrimps survived out of 30. The oils showed no antibacterial and insecticidal activity against the test organisms. Key words: Essential oil, Acacia modesta, antibacterial, antifungal, phytotoxic, insecticidal brine shrimp cytotoxicity.

Fractional Distillation Process Utilized to Produce Light Fractional Fuel from Low Density Polyethylene (LDPE) Waste Plastic

Plastics are not easily biodegradable; and because of these characteristics they can remain under landfill and water for a very long period of time. All over the world only 6% of waste plastics are recycled and the rest of all waste plastics are dumped into landfills. An experiment was conducted in a laboratory scale batch process under Labconco’s fume hood utilizing low density polyethylene (LDPE). The experiment was carried out to obtain a hydrocarbon fuel product utilizing thermal degradation. Many research studies have successfully demonstrated that waste plastics such as low density polyethylene (LDPE), high density polyethylene (HDPE), polypropylene (PP) and polystyrene (PS) can be converted to valuable liquid hydrocarbon fuels. For experimental purposes we used 500 gm of LDPE as raw materials. This particular experiment is a two step process; the first step process involves extracting hydrocarbon fuels as mixture of both short and long chain hydrocarbon compounds. During the second step the fuel obtained in the first process is refractionated by thermal degradation process utilizing a distillation column. This process yields a short hydrocarbon chain liquid fuel that has similar properties to gasoline grade fuels. Analysis of these fuels was conducted by Gas Chromatography and Mass Spectrometer (GC/MS), FT-IR Spectrum 100 and Differential Scanning Calorimeter (DSC). The results show that the produced fuels are good quality fuels with high energy content. ASTM test result indicates that fuel has low sulfur level (3.2 ppm) and the fuel hydrocarbon range shown by GC/MS analysis is C4-C10.

Composition, in vitro antioxidant and antimicrobial activity of the essential oils from Artemisia lavandulaefolia DC.

The essential oils from the aerial parts of Artemisia lavandulaefolia DC., a traditional medicinal plant growing in China, were obtained by hydro distillation and analyzed by gas chromatograph and mass spectrometer (GC-MS). Fifteen monoterpenes, six sesquiterpenes, three monoterpenoid acetates with two aromatic compounds and two others were identified among twenty-eight compounds, representing 99.69% of the total oils. Eucalyptol (20.62%), Borneol (15.32%), Eudesm-7(11)-en-4-ol (13.81%), Sabinol (9.75%), β-Terpineol (6.86%), trans-Pinocarvyl acetate (6.13%) and α-Terpineol (5.35%) were the major seven compounds in the essential oils. The essential oils displayed significant in vitro antimicrobial activities againstBacillus subtilus, Pseudomonas aeruginosa, Bacillus cereus1 and Staphylococcus aureuswith minimum inhibitory concentration values range of 125 to 250 μg/ml. The in vitro antioxidant activities were assessed by DPPH radical scavenging and inhibition of lipid peroxidation methods. The oils showed a remarkable free radical scavenging activities, as evidenced by the low IC50 value for DPPH radical (275.7 μg/ml) and inhibition of lipid peroxidation (induced by FeSO4, H2O2 and CCl4) with IC50 values of 393.6, 562.8 and 297.2 μg/ml, respectively. Key words: Artemisia lavandulaefolia DC., antioxidant activities, antimicrobial activities, essential oils.

Phytochemical and antimicrobial activities of Lavandula officinalis leaves and stems against some pathogenic microorganisms

The leaves and stem-bark of Lavandula officinalis were investigated for activity against some pathogenic organisms. Phytochemical screening revealed the presence of coumarins, tannins, flavonoids, volatile oil and fatty acids. Twenty six and twenty were characterized representing 84.5% (leaf oil) and 91.4% (stem oil) of the lot of components detected. The leaf oil of the major constituents was identified as borneol (23.6%), 1, 8-cineol (17.6%), camphor (12.6%). In the stem oil of plant 1, 8cineol (20.8%), borneol (19.2%), α-cadinol (11.3%), caryophyllene oxide (10.4%) and camphor (7.4%) were the predominating compounds . The hexane extracts of leaf and stem of plant were obtained by soxhlet apparatus. The fatty acids were derived to methyl esters and determined by gas chromatograph and mass spectrometer (GC/MS) systems. The main components of the leaf and stem (hexanic extracts) were ω-3 (43.2 and 21.0%), ω-6 (3.4 and 14.5%), palmitic acid (7.4 and 12.4%) and Bis (2-ethylhexyl) phthalate (12.8 and 16.7%), respectively. Antimicrobial activities of the crude methanol, hexane extracts and essential oil from leaf and stem were evaluated using agar diffusion method. Results, suggest potential antimicrobial activity of the essential oil and extracts of L. officinalis, which may find those application in future research for the food and pharmaceutical industry.