Type Apparatus Research Articles

Measurement of High-Pressure Densities and Atmospheric Viscosities of Ionic Liquids: 1-Hexyl-3-methylimidazolium Bis(trifluoromethylsulfonyl)imide and 1-Hexyl-3-methylimidazolium Chloride

Atmospheric densities and viscosities of ionic liquids, 1-hexyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([C6C1Im][Tf2N]) and 1-hexyl-3-methylimidazolium chloride ([C6C1Im][Cl]), were measured with a Stabinger viscometer at temperatures from (293 to 373) K. High-pressure densities (p ≤ 200 MPa) for [C6C1Im][Tf2N] and [C6C1Im][Cl] were measured with a bellows type apparatus at temperatures from (312 to 452) K. Samples were analyzed for the water and 1-methylimidazole content before and after the measurements. For [C6C1Im][Tf2N], combined expanded uncertainties were estimated to be (1.0 and 1.8) kg·m–3 for atmospheric and high-pressure density, respectively, and 0.85 % for viscosity. For [C6C1Im][Cl], combined expanded uncertainties were estimated to be (1.1 and 2.5) kg·m–3 for atmospheric and high-pressure density, respectively, and 1.59 % for viscosity. The measured densities and viscosities of [C6C1Im][Tf2N] in this work agreed with some of the available literature values within their experimental uncertainties. The effect of colored impurities and the source of sample on densities and viscosities of [C6C1Im][Cl] were determined to be less than the experimental uncertainties. The [C6C1Im][Tf2N] did not decompose over the full temperature range during the measurements, while [C6C1Im][Cl] decomposed at temperatures greater than 392 K.

Hydrogen storage of nanocrystalline Mg–Ni alloy processed by equal-channel angular pressing and cold rolling

Ball-milled nanocrystalline Mg2Ni powders were subjected to intense plastic straining by cold rolling or equal-channel angular pressing. Morphological and microstructural evolution during these processes has been investigated by scanning electron-microscopy and X-ray diffraction line profile analysis, respectively. Complementary hydrogen absorption experiments in a Sieverts' type apparatus revealed that there exists some correlation between the micro- and nanostructure and hydrogen storage properties of the severely deformed materials.

English

Artemisia dracunculus L. (Tarragon) is a species of flowering plant within the family Asteraceae, commonly used as a dietary seasoning. During the present study, the plant was collected from Indian Institute of Integrative Medicines (IIIM Srinagar). Air dried shoots (room temperature 25-35°C) were used to extract essential oil using Clevenger type apparatus for 3 h and analyzed. Thirty-four (34) compounds were identified using gas chromatography- flame ionization detector (GC-FID) and Gas chromatography-mass spectrometry (GC-MS) analysis. Major constituents of the essential oil were trans-Anethole (28.06%), Z-β-ocimene (15.79%), a- Terpenolene (10.12%), Elemecin (10.08%), 1, 8 cineole (7.71%) and a-copaene (2.78%), etc. Comparing our results with those of other Artemisia species already published in the literature revealed considerable qualitative and quantitative similarity of the major constituents of the essential oils. As trans-Anethole is the major constituent, this chemo type may be useful for industrial exploitation as well as chemotaxonomic characterization. Key words: Artemisia dracunculus, Terpenolene, Z-β-ocimene, trans-Anethole.

Methane storage in zeolite-like carbon materials

High specific surface area zeolite-like carbon materials (CZ) were synthesized by combining the hard template method with the Chemical Vapor Deposition (CVD), using zeolite beta as solid template and acetylene as carbon precursor, at different reaction temperatures (1023, 1073 and 1123K). CZ materials were characterized by X-ray diffraction, Scanning Electron Microscopy and nitrogen adsorption–desorption measurements. The nanoporous CZ materials possess surface areas up to 1130m2/g and total pore volumes up to 0.75mL/g while XRD data and SEM images show the successful replication of the structure and morphology of the zeolite particles into the final carbon materials. Methane storage properties at different temperatures (287, 298 and 313K) have been investigated by Sievert’s-type apparatus up to 3.5MPa. The CZ materials exhibit a high and reversible methane storage capacity, with measured gravimetric uptake up to 8.0wt% at 298K and 3.5MPa, a much higher value compared to the pristine zeolite beta which shows gravimetric methane adsorption capacity up to 1.5wt% at the same conditions. The analysis of the obtained isotherm curves by Tόth model shows the same grade of homogeneity on sample porosity for all probed samples while the evaluation of the adsorption enthalpy at low pressures reveals a similar binding energy between the methane molecules and the samples’ surfaces despite of their different long range order.

Hydrogen sorption properties of 90 wt% MgH2–10 wt% MeSi2 (Me = Ti, Cr)

The hydriding/dehydriding characteristics of 90 wt% MgH2–10 wt% MeSi2 (Me = Ti, Cr) composites, synthesized by ball milling under argon, were studied by Sievert’s type apparatus and by high-pressure differential scanning calorimetry (HPDSC). The composites have demonstrated similar absorption kinetics and capacity at temperature of 300 °C and a pressure of 1 MPa. They showed fast kinetics and achieved absorption capacity higher than 6 wt%. Slightly higher values for the enthalpy of hydriding and dehydriding were obtained at scanning conditions in the HPDSC for the composite 90 wt% MgH2–10 wt% CrSi2 compared to those for the composite with addition of TiSi2.

Kinetic behaviour of a metal-polymer composite suitable for hydrogen storage applications

Hydrogen storage in composite materials is a feasible way to overcome the main drawbacks of the metal hydride systems. In the present paper, we report on the hydrogenation properties of three polydimethylsiloxane (PDMS)–palladium composite samples with different content of metallic fraction (5, 15, 50 in wt.%). Hydrogenation tests in different conditions of temperature and pressure were performed using a Sievert's type apparatus, while the microstructure of the samples was characterised by means of scanning electron microscopy observations and X-ray diffraction measurements. Results show that the hydrogen storage capacity is inversely proportional to the metallic content in the composite samples.

Fabrication and Tribological Properties of Al-Si/B4C Metal Matrix Composites

Aluminium composite materials are exponentially growing up and rapidly gaining importance because of their properties like low density, high strength, high stiffness, environmental resistance, low co-efficient of thermal expansion etc. In this context aluminum-boron carbide composites, with 2.5, 5 and 7.5 wt% of boron carbide (B4C) particulate reinforced, were prepared by stir casting process and the effect of the percentage of reinforcement of B4C on dry sliding wear and friction coefficient were investigated. The wear tests were carried out on a pin-on-disc type apparatus at a linear speed of 1m/s, sliding distance of 500 m and a constant load of 30 N. The coefficient of friction was recorded on line. Wear rates were calculated from mass loss measurements. Scanning electron microscope was used to examine the tribo-surface of worn Al- B4C composites. The results showed that the wear rate of 7.5 wt% B4C composites is 0.375 mg/min which is significantly lower than pure Al alloy (3.125 mg/min). The friction coefficient decreases from 0.477(for pure Al alloy) to 0.261(for 7.5 wt% B4C composites).

Design of Drum Type Apparatus for Processing of Bulk Materials

The article presents the development and research of drum continuous mixers, most attention is paid to the results of theoretical (using of cybernetic approach) and experimental studies of longitudinal mixing particulate material in rotating drums of continuous action, the influence of internal recycles of material flows, intensifying the process of smoothing the input fluctuations. The authors analyzed the influence of internal recycles material flows, intensifying the process of smoothing the input fluctuations. The results presented in this paper were obtained by the experiments on the smoothing ability determination during which they change the frequency of the drum rotation, the location of the Г-shaped mixer blades on the drum mixer. The article reported that the studies were conducted on three mixtures which components have different physical and mechanical systems with various dispersed liquid additives and without it.

DEVELOPMENT OF CAN PASTEURIZATION WITH REFERENCE TO CONTINUOUS OPEN TYPE APPARATUS

In the paper are considered the problems connected with the development of scientifically valid can pasteurization regimes in the self-exhaustion tare in continuous open type apparatus operating under atmosphere pressure. By the results of carried out researches is established that the use of ‘breathing’ type allows to reduce apparatus time of thermal treatment on average 25% provided the achievement of necessary lethality of pasteurization regimes.

Chemical composition of the essential oil of Artemisia austriaca JACQ. growing wild in Iran

Objective: The genus Artemisia (Asteraceae) comprises approximately 400 species of commonly perennial and fragrant herbs distributed in the northern temperate region of the world. Artemisia austriaca JACQ. is one of the most common species of the genus distributed from central Europe to Siberia, Turkey, and Iran. In Iran, the plant is indigenous to East Azerbaijan and Ardabil province. In the present study, the essential oil composition of the aerial part of Artemisia austriaca and some allelopathic potential of the oil were studied. Methods: The essential oil of the plant was obtained by hydrodistillation using a clevenger type apparatus. After dehydratation, the essential oil was analyzed by GC and GC-MS. Results: The results showed that the camphor (15.88%), 1,8-cineole (10.75%), camphene (3.53%) and beta-fenchyl alcohol (3.03%) were the main components among 51 constituents characterized in the oil. The plant essential oil showed significant anti-sclerotinia and phytotoxic activity. Conclusion: Our findings indicated that there is a high level similarity between the major compound of essential oil of A. austriaca samples collected from northwest of Iran, Ardabil, and Turkey. Accordingly, the two samples may represent the same chemotype. On the other

Glucosinolates of Lunaria annua: thermal, enzymatic, and chemical degradation

Lunaria annua (L.) (annual honesty) belongs to Brassicaceae family. The goal of the present study was the isolation of the essential oil by hydrodistillation using a Clevenger type apparatus. In addition, in order to identify glucosinolates, other means of their degradation were applied (enzymatic, chemical). The resulting volatiles were subsequently extracted by CH2Cl2, and analyzed by GC and GC-MS.

Chemical Composition and Insecticidal Properties of the Essential Oil of Salvia leriifolia Benth (Lamiaceae) at Two Developmental Stages

Aromatic plants contain both volatile and non-volatile fractions and the chemical composition of these two fractions may be influenced by seasonal changes. Salvia leriifolia Benth (Lamiaceae) was collected at two developmental stages and at the same locality throughout the 2011 growing season, were compared in terms of essential oil composition, yields and toxicities. The first collection was done during the month of March (vegetative stage). Later collection was done during May (flowering stage). Dry ground leaves were subjected to hydrodistillation using a Clevenger type apparatus and the chemical composition of the volatile oils was studied by gas chromatography-mass spectrometry (GC-MS). The components that varied seasonally included 1,8-cineole and β-pinene (highest in May: 34.76 and 21.09 %, respectively), γ-cadinene and α- cadinol (highest in March: 6.89 and 4.42 %, respectively). Contact and fumigant toxicities of oils was investigated against adults of cowpea weevil Callosobruchus maculatus (Fab.), rice weevil Sitophilus oryzae (L.), and red flour beetle Tribolium castaneum (Herbst). Both oils in the same concentrations were tested for their toxicities on each species. The mortality of 1-7 day old adults of the insect pests increased with rates of oils and exposure time. Results showed that May oil were more toxic than March oil against insect species. Contact and fumigant effects of these essential oils were considered to warrant further research into their potential for commercial use.

Fast low-temperature consolidation of a nanostructured 2Ti–ZrO2 composite for biomedical applications

TiO and Zr powders were milled by high energy ball milling and horizontal ball milling. The milled powders were then consolidated using high frequency induction heated sintering (HFIHS) within 4min under the applied pressure of 1GPa. The milling did not induce any reaction between the constituent powders. Meanwhile, HFIHS of the TiO–Zr mixture produced a Ti–ZrO2 composite according to the reaction (2TiO+Zr→2Ti+ZrO2). The average hardness and fracture toughness of the nanostructured 2Ti–ZrO2 composite sintered from high energy ball milled powder were 1002kg/mm2 and 6.8MPam1/2, respectively. The fracture toughness of the 2Ti–ZrO2 composite was significantly higher due to the presence of ductile Ti synthesized during sintering. The wear resistance of the composite was measured using a pin-on-disc type apparatus. Cell viability was also analyzed by absorbance of the composite using CCK-8 solution.

Heat of absorption and absorption capacity of CO2 in aqueous solutions of amine containing multiple amino groups

This study investigated the characteristics of polyamines that have two or more amino groups in their structure. They are expected to show better performance than existing absorbents due to the increased number of amino groups that can react with CO2. A semi-batch type apparatus was used to measure the absorption capacity of CO2 at the temperature range of 313–353K. The quantity of heat generated by the absorption of CO2 in the absorbents was measured with a differential reaction calorimeter (DRC) for comparison with those of aqueous solutions of MEA and DEA at 298K. The absorbents were evaluated from the aspects of the absorption capacity of CO2 and heat of absorption, and the characteristics according to the increasing number of amino groups were considered.

Hydrogen Adsorption Study upon Ni/Al2O3 Nano-composite Synthesized by MOCVD Technique

The hydrogen adsorption (storage) studies upon M/AI2O3 nano-composite prepared by metal organic chemical vapor deposition technique (MOCVD) exploiting single source molecular precursor (SSP) approach were carried out. The Ni/Al2O3nano-composite is prepared in cold walled MOCVD reactor by the decomposition of SSP, [H2Al(OtBu)]2, on a substrate holding Ni(acac)2 powder. The SSP is a reducing agent which reduces Ni+2 to Ni0 and works as source for Al2O3 matrix in which the Ni0 is dispersed. The resulting Ni/Al2O3 nano-composite is characterized by XRD, SEM, TEM, and EDX. The hydrogen adsorption (storage) studies are performed using home-made Sievert's type apparatus. The hydrogen storage studies reveal that approximately 2.9% (mass ratio) hydrogen can be stored in the Ni/Al2O3 nano-composite. The results show that Ni/Al2O3 nano-composite can be a potential candidate for hydrogen storage which can be used for onboard fuel purposes.

Chemical Composition and Insecticidal Activity of Essential oil obtained from DCM Extracts of Psoralea corylifolia against Agricultural pest

The insecticidal activity of essential oils obtained from DCM extracts of Psoralea corylifolia (Fabaceae) against pupa of Epilachna insect was investigated in a series of laboratory experiments. Insecticidal activity was determined at 24 ± 4°C and 68 ± 5% R.H., in dark conditions. The DCM extracts of the dried seeds of the plants were subjected to Column chromatography and the oil obtained was then subjected to hydrodistillation using a Clevenger type apparatus. The major components in these essential oils are identified using GC-MS spectroscopy and their insecticidal activity was tested. The predominant components in the oil of Psoralea corylifolia are toluene, alpha-pinene, L-beta-pinene, beta-pinene, 3-carene, limonene, Gamma terpinene, terpinolene, alpha santolina alcohol, 4-terpineol, Cyclohexene, 1-methyl-4-(1-methyl ethenyl), caryophyllene, alpha caryophyllene, thumbergene. The mortality rate of the agricultural pests was checked against 1%, 5% and 10% conc. of essential oil. The essential oil from Psoralea corylifolia shows strong toxic effect against pupa of Epilachna insect. Finding insecticidal activity is of great importance as using plant extracts as insecticides, are biodegrable and do not leave toxic residues results in better crop and better human health.

Chemical Composition and Cytotoxicity Evaluation of Essential Oil from Leaves of Casearia Sylvestris, Its Main Compound α-Zingiberene and Derivatives

Casearia sylvestris (Salicaceae), popularly known as “guaçatonga”, is a plant widely used in folk medicine to treat various diseases, including cancer. The present work deals with the chemical composition as well as the cytotoxic evaluation of its essential oil, its main constituent and derivatives. Thus, the crude essential oil from leaves of C. sylvestris was obtained using a Clevenger type apparatus and analyzed by GC/MS. This analysis afforded the identification of 23 substances, 13 of which corresponded to 98.73% of the total oil composition, with sesquiterpene α-zingiberene accounting for 50% of the oil. The essential oil was evaluated for cytotoxic activity against several tumor cell lines, giving IC50 values ranging from 12 to 153 μg/mL. Pure α-zingiberene, isolated from essential oil, was also evaluated against the tumor cell lines showing activity for HeLa, U-87, Siha and HL60 cell lines, but with IC50 values higher than those determined for the crude essential oil. Aiming to evaluate the effect of the double bonds of α-zingiberene on the cytotoxic activity, partially hydrogenated α-zingiberene (PHZ) and fully hydrogenated α-zingiberene (THZ) derivatives were obtained. For the partially hydrogenated derivative only cytotoxic activity to the B16F10-Nex2 cell line (IC50 65μg/mL) was detected, while totally hydrogenated derivative showed cytotoxic activity for almost all cell lines, with B16F10-Nex2 and MCF-7 as exceptions and with IC50 values ranging from 34 to 65 μg/mL. These results indicate that cytotoxic activity is related with the state of oxidation of compound.

Development of coupled shear-flow-visualization apparatus and data analysis

A new type apparatus for shear-flow coupling test, named coupled shear-flow-visualization apparatus, was developed to investigate the hydromechanical behavior and the fracturing process of intact soft sedimentary rock. With this apparatus, it is possible to simultaneously carry out direct shear test and constant head flow test, and also to observe specimen surface during the experiment. Under controlled shear load, normal load, flow rate and shear displacement can be obtained as raw data. Moreover, fracture area and fracture apertures can be estimated using image-processing techniques. The shear and normal stress capacities of load cells are 4.08MPa and 3.33MPa, respectively. The measurable maximum permeability of apparatus is about 5.80×10−3cm/s under a hydraulic gradient of 40cm/cm. According to the observation of visible fractures on specimen surface, the fractures were not completely propagated at the peak of shear stress. The developed testing method with image processing techniques enabled us to analyze the relationships between fracture flow rate, hydraulic aperture and two fracture apertures defined in this study.

Effect of Sr on microstructure, tensile properties and wear behavior of as-cast Mg–6Zn–4Si alloy

The microstructure, tensile properties and wear behavior of as-cast Mg–6Zn–4Si alloy with strontium additions at ambient and elevated temperature were investigated by means of X-ray diffraction (XRD), optical microscopy (OM), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), standard high temperature tensile testing and a pin-on-disc type apparatus. The results indicated that the grain size of the primary Mg2Si decreased initially and then gradually increased with increasing Sr amount. Meanwhile, the morphology of the primary Mg2Si in the alloys changed from large dendritic to polygonal or fine block, and that of the eutectic Mg2Si phase turned to fine fibre with increasing Sr content. Tensile testing results showed that Sr addition improved the ultimate tensile and elongation of the Mg–6Zn–4Si alloys at both ambient temperature and 150°C. Dry sliding wear tests indicated that the change trend of wear rate was basically coincident with that about the average size of the primary Mg2Si phases. Optimal mechanical properties and wear behavior could be achieved by a Sr addition of 0.5%. An excessive Sr addition resulted in the formation of the needle-like SrMgSi compound, which was detrimental to the tensile properties and wear behavior of the alloys.

Experimental Measurements and Correlation of the Solubility of Three Primary Amides in Supercritical CO2: Acetanilide, Propanamide, and Butanamide

Solubilities of three primary amides, namely, acetanilide, propanamide, and butanamide, in supercritical carbon dioxide were measured at T = (308.2, 313.2, and 323.2) K over the pressure range (9.0 to 40.0) MPa by a flow type apparatus. The solubility behavior of the three solids shows an analogous trend with a crossover region of the respective isotherms between (12 to 14) MPa. The solubility of each amide, at the same temperature and pressure, decreases from propanamide to acetanilide. Pure compound properties required for the modeling were estimated, and the solubilities of the amides were correlated by using the Soave–Redlich–Kwong cubic equation of state with an absolute average relative deviation (AARD) from (1.3 to 6.1) %.