Tricyclic terpanes to hopanes Ratios calculated from individual biomarkers to delineate their distribution, identifications, mixing ratios and biological precursor in a suite of crude oils (n = 24) from the East Sirt Basin. Geochemical application of Tricyclic terpane and Hopane biomarkers is divided studied oils into five groups (I, II, III, IV and V) based on the different ratios between Tricyclic terpanes to hopanes. Percentages of C23 Tricyclic terpanes/17α (H), 21β(H)-hopanes (C30αβ) and C28 Tricyclic terpane/17α (H), 21β (H)-30 hopanes (C31) have divided crude oils into 2 main individual groups in addition to 3 mixed groups. Group I, characterized by the dominance and extension of the tricycle terpane series (≈ C45 Tricyclic terpane). Group V, distinguished with the dominance of 17α (H), 21β (H) hopanes series. Groups II, contained a domination Tricyclic terpanes and hopanes, considered as a mixed group. The group III demonstrated equivalent ratios of Tricyclic terpanes to hopanes. The Group IV revealed a reduced amount of Tricyclic terpanes with enrich of hopanes. Tricyclic terpanes derived from tricyclohexaprenol precursors and attributed to a marine depositional environment and algal matter. Hopanes in obtained from bacteriohopane polyols and aminopolyols and distinguished to a depositional bacterial environment.

The influence of physical (external added weight) and neurophysiological (fatigue) factors on static and dynamic balance in sport related activities was typified statically by the Romberg test (one foot flat, eyes open) and dynamically by jumping and hopping in both horizontal and vertical directions. Twenty healthy males were participated in this study. In Static condition, added weight increased body-s inertia and therefore decreased body sway in AP direction though not significantly. Dynamically, added weight significantly increased body sway in both ML and AP directions, indicating instability, and the use of the counter rotating segments mechanism to maintain balance was demonstrated. Fatigue on the other hand significantly increased body sway during static balance as a neurophysiological adaptation primarily to the inverted pendulum mechanism. Dynamically, fatigue significantly increased body sway in both ML and AP directions again indicating instability but with a greater use of counter rotating segments mechanism. Differential adaptations for each of the two balance mechanisms (inverted pendulum and counter rotating segments) were found between one foot flat and two feet flat dynamic conditions, as participants relied more heavily on the first in the one foot flat conditions and relied more on the second in the two feet flat conditions.

The Muslim faith requires individuals to fast between the hours of sunrise and sunset during the month of Ramadan. Our recent work has concentrated on some of the changes that take place during the daytime when fasting. A questionnaire was developed to assess subjective estimates of physical, mental and social activities, and fatigue. Four days were studied: in the weeks before and after Ramadan (control days) and during the first and last weeks of Ramadan (experimental days). On each of these four days, this questionnaire was given several times during the daytime and once after the fast had been broken and just before individuals retired at night. During Ramadan, daytime mental, physical and social activities all decreased below control values but then increased to abovecontrol values in the evening. The desires to perform physical and mental activities showed very similar patterns. That is, individuals tried to conserve energy during the daytime in preparation for the evenings when they ate and drank, often with friends. During Ramadan also, individuals were more fatigued in the daytime and napped more often than on control days. This extra fatigue probably reflected decreased sleep, individuals often having risen earlier (before sunrise, to prepare for fasting) and retired later (to enable recovery from the fast). Some physiological measures and objective measures of performance (including the response to a bout of exercise) have also been investigated. Urine osmolality fell during the daytime on control days as subjects drank, but rose in Ramadan to reach values at sunset indicative of dehydration. Exercise performance was also compromised, particularly late in the afternoon when the fast had lasted several hours. Self-chosen exercise work-rates fell and a set amount of exercise felt more arduous. There were also changes in heart rate and lactate accumulation in the blood, indicative of greater cardiovascular and metabolic stress caused by the exercise in subjects who had been fasting. Daytime fasting in Ramadan produces widespread effects which probably reflect combined effects of sleep loss and restrictions to intakes of water and food.

This study is aimed at investigating the interactive effects of reaction parameters such as temperature (330–370 °C), total pressure (30–50 bar) and liquid hourly space velocity LHSV (1–3 h⁻¹) on the performance of hydrodesulfurization (HDS) activity. Experiments were performed based on the central composite rotatable design and analyzed using the response surface methodology (RSM). First, the equation model is used to predict HDS activity as a response. Second, the regression analysis of the HDS activity model is obtained from the output of this developed model. Finally, the RSM and canonical analysis is used to optimize this empirical regression model. R ² = 96.5 % showed that the RSM model fitted the observed data well with and is considered to be accurate and available for predicting HDS activity. The obtained equation for the canonical analysis with different signs of eigenvalues …

This study aimed to identify the impact of domestic investment as a determinant of growth in the Libyan economy during the period (1962-2008). Cobb-Douglas Function was used to analyze the relationship between real per-capita GDP and its most important determinants as described in Cobb-Douglas function. Properties of time series of the model variables have been analyzed by using several tests for determining the integration level of each time series separately. By using Johansen approach, the results showed the significance of the impact of investment on per-capita GDP, the results of tests revealed equilibrium relationship between per-capita GDP and its determinants in the

long and short-run. The study concluded that the elasticity of per-capita GDP to changes in domestic

investment is greater than the elasticity of labour force which appeared inelastic in the short and long-term.

ABSTRACT

In order to capture the effect of joint progressive stiffness degradation with the hardening effect taken into account, the three parametric continuous model is adopted hereafter for the analytical formulation. The current paper is an extension of the previous work (Gizejowski et al. 2012) giving all the details of the developed model together with a calibration procedure for basic model parameters. Experimental data used was obtained from laboratory tests carried out at the Warsaw University of Technology for beam-to-column joints of different reinforcement ratio. The results of calibration exercise as well as the values of calibrated model parameters are given for practical application.

This study focuses on methylol functional benzoxazines as precursors to build a network structure utilizing both benzoxazine and resole chemistry. The first part is a review of systems that contain methylol groups which play a role on their crosslinking formation. The polymerization mechanism and properties of resoles will be highlighted as the most abundant polymers that are characterized by polymerization through condensation reaction of methylol group. In the second part, the effect of incorporating methylol group into benzoxazine monomers is studied. Differential scanning calorimetry (DSC) is used to study the effect of methylol group on the rate of polymerization. Kissinger and Ozawa methods using non-isothermal DSC at different heating rates show that methylol monomer exhibits lower average activation energy compared to the un-functionalized monomer. The effect of adding catalysts into the monomers is …