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The study aims to characterize the structural features of Jordanian tar sand using analytical techniques including (FTIR, ultimate and proximate analysis, TGA, XRD, and XRF). The tar sand shows a low content of volatile matter (bitumen) with significant nitrogen content. The bitumen contains a high proportion of aliphatic hydrocarbons of which high content of it attached to oxygen atom. The minerals were mainly quartz and low concentration of carbonate with noticeable content of sulfite and potassium oxide from XRF. The recovery of bitumen was evaluated using three different extraction techniques: solvent extraction methods (ultrasound-assisted extraction, non-aqueous extraction) and thermal pyrolysis using the Fischer assay apparatus. The non-aqueous solvent extraction method gave the highest bitumen recovery using toluene as a solvent; however, the high-temperature Fischer assay method provided a low recovery. The extracted bitumen under the optimum condition was characterized using NMR, elemental analysis, and GC-MS analysis. The oil products from tar sand showed a high concentration of oxygen and noticeable concentration of sulfur atoms. The 1H-NMR revealed a high content of aliphatic hydrocarbons in good agreement with raw tar sand characteristics. The identified compounds in the GC-MS where mainly substituted with oxygen atom in the form of alcohols and ethers. [ABSTRACT FROM AUTHOR]

Jordanian kaolinite was treated with two phosphate modifiers: sodium polyphosphate (MK 1) and sodium hexametaphosphate (MK 2). Both raw and modified kaolinites were characterised by XRD and FTIR techniques. The adsorption behaviour of Th(IV) and U(VI) ions onto the two modified kaolinites were studied as a function of dosage, contact time, pH and temperature. The adsorption isotherm of both metal ions onto modified kaolinite was investigated using Langmuir, Freundlich and Dubinin–Radushkevich (D-R) models, which fits better to the Langmuir model. MK 1 kaolinite showed higher metal ion uptake than MK 2 kaolinite for both ions. The metal ion uptake of Th(IV) ions on both modified kaolinites was significantly higher than that of U(VI) ions. The % adsorption efficiency (73.8 and 69.0%) of Th(IV) ions on MK 1 and MK 2 was significantly higher than that of U(VI) ions (35.0 and 13.3%). The adsorption capacities for Th(IV) (188.7 and 9.6 (mg/g)) and U(VI) (53.5 and 15.3(mg/g)) were improved when MK 1 and MK 2 kaolinites were used at 25°C. The thermodynamic studies indicated that the removal of U(VI) and Th(IV) ions using both modified kaolinites is spontaneous and favourable at higher temperatures. The positive entropy values indicated that the adsorption process increased the disorder of the system. The kinetic study had indicated that the pseudo-second-order kinetic model fit the adsorption data, suggesting a chemisorption nature of the adsorption process. Binary system experiments under optimised conditions showed higher removal of Th(IV) ions compared to U(VI) ions. The desorption study showed that the elution of both metal ions increased as the concentration of HNO3 increased. Both the modified kaolinites were regenerated three times, a slight reduction of their adsorption efficiency was observed, and the presence of interferences has the same effect. [ABSTRACT FROM AUTHOR]

Oil shale is a raw material that is considered to be an alternative fossil fuels and it is widely used in producing energy and chemicals. Oil shale bitumen identification are not widely described in literature. This article tackles the structural elucidation of oil shale bitumen using gas chromatography-mass spectrometry (GC-MS) and nuclear magnetic resonance (NMR) spectroscopy with a short sample preparation step, based on ultrasonic-assisted liquid extraction. The ultrasonic-assisted extraction was examined in terms of solvent type and volume, sample size, sonication time and temperatures. A bitumen recovery of 17.7 wt% dmmf (dry-mineral-matter-free) was achieved when 0.50 g of shale was mixed with 20 mL THF and sonicated for 10 min at ultrasonic power of 120 W at 45°C. GC-MS of the bitumen showed high polar oxygenated compounds with more than 20 wt% being esters and ethers. Small concentrations of thiols and amides have been also found. The structural identification of bitumen was carried out using 1H-NMR and 13C-NMR and the results showed highly aliphatic character bitumen, consisting of aromatic, paraffinic, naphthenic and olefinic hydrogen and carbon atoms. These results suggested that ultrasonic solvent extraction could be an efficient and environment-friendly method for obtaining of bitumen from oil shale. [ABSTRACT FROM AUTHOR]

Aims: We aimed to investigate the effect of various vaginal wash solutions on reducing risks of post‐cesarean endometritis, wound infections, fever, and hospital stay duration. Methods: Scopus, Web of Science, PubMed, and Cochrane Library were searched for randomized clinical trials that compared different vaginal wash solutions to each other or to "no vaginal cleaning"; without restriction on the age of parturients or site where trials were conducted. We analyzed this frequentist network meta‐analysis using the netmeta package in R software version 4.1.2; synthesized data as mean difference or risk ratio with their 95% confidence intervals. Results: Our network meta‐analysis included 29 RCTs with a total sample size of 9311 women undergoing CS. Regarding post‐cesarean endometritis, we found that povidone‐iodine had the highest significant risk reduction compared to "no vaginal cleaning" (RR = 0.08, 95% CI [0.01, 0.69]). While regarding post‐cesarean reduction of wound infection, fever, and hospital stay duration, we found that chlorhexidine 4% (RR = 0.17, 95% CI [0.05, 0.65]), saline 0.9% (RR = 0.12, 95% CI [0.03; 0.48]), and saline 0.9% (MD = −1.29, 95% CI [−2.18; −0.39]), respectively, had the highest significant risk reduction compared to "no vaginal cleaning." Conclusion: Vaginal wash solutions were associated with a significant reduction of post‐cesarean endometritis, wound infection, fever, and hospital stay duration. Since povidone‐iodine had the highest significant reduction of post‐cesarean endometritis, we recommend setting povidone‐iodine as the standard practice as pre cesarean vaginal wash solution; consistent practice guidelines of Enhanced Recovery After Surgery (ERAS). [ABSTRACT FROM AUTHOR]

This study seeks to identify the impact of e-learning on teaching reading of the English language from the point of view of English language teachers and supervisors in Jordan. It also aims at identifying several study variables such as gender, age, marital status, qualification, experience, and number of training sessions by distributing a 36-item questionnaire among 55 teachers. To achieve the study purpose, the questionnaire has been gathered, codified, entered into the computer, and stylized by using SPSS. The study showed a very high degree on the main question about the impact of e-learning on teaching reading of the English language from the point of view of English language teachers and supervisors in Jordan. Also, it showed that there are no statistically significant differences at (α=0.05) in the impact of e-learning on teaching reading of the English language from the point of view of English language teachers and supervisors in Jordan attributed to the variables of gender, age, marital status, qualification, experience and number of training sessions. Several recommendations have been suggested including the necessity of taking care of e-learning and more studies about the same subject. [ABSTRACT FROM AUTHOR]

This article presents a single-objective modulated model predictive control for a bidirectional dc–dc flying-capacitor (FC) converter in a microgrid. The presence of an FC facilitates the converter to integrate a low-voltage battery to a high-voltage dc bus at reduced voltage stress on its power switches. The converter in such a configuration demands a multiobjective controller to accomplish dc bus and FC voltage regulations and bidirectional power flow. The proposed controller realizes these multiple control objectives by determining the optimum duty ratio for the power switches using a single-objective cost function based on the battery current. In doing so, the converter realizes its multiple control objectives without weighting factors in the cost function and operates its power switches at a fixed switching frequency. The proposed controller also eliminates an additional control loop by utilizing an improved dynamic reference model to generate an appropriate battery current reference for the dc bus voltage regulation and bidirectional power flow. Finally, the proposed system is validated experimentally under step response of the dc bus voltage, load, PV power, and system parameter variations, and compared with a finite control set model predictive control to prove its effectiveness. [ABSTRACT FROM AUTHOR]

Thermal degradations of biomass corn leaves were studied for kinetic modeling. Thermogravimetric-differential analyzer runs at 5, 10, 20, and 30 °C min−1 heating rates were employed. Apparent activation energy and frequency factor values were calculated for first-order kinetics using several procedures. The procedure of Coats and Redfern showed 28.89 to 31.78 kJ mol−1 apparent activation energy and 15.5 to 157.12 min−1 frequency factor, respectively. Calculation of the apparent activation energy and frequency factor using Kissinger–Akahira–Sunose procedure gave 229.9–364.2 kJ/mol and 8.567 × 1023 and 1.13 × 1031 (min−1), respectively as the conversion increased from 0.1 to 0.9. The newly introduced excel solver procedure indicates a distribution activation energy over the entire range of conversion. For first-order reaction kinetics, the calculated apparent activation energy magnitudes ranged between 5.0 kJ mol−1 with frequency factor equals to 0.239 and 196.2 kJ mol−1 with frequency factor 2.89 × 1012 in the studied range. The low or high magnitudes of the calculated activation energy are not associated with a particular value of the conversion. The calculated apparent activation energies are related to the direct solution of the simultaneous equations that constitute the basis of the excel solver. [ABSTRACT FROM AUTHOR]

Multiple primary malignancies are defined as two or more primary malignant tumors diagnosed in one individual; they are further classified to synchronous or metachronous based on the period between each cancer diagnosis and the other. The diagnosis of four synchronous cancers is exceedingly rare. We report a case of a 72-year-old man, diagnosed with synchronous quadruple cancers, Hurthle cell carcinoma and papillary carcinoma of the thyroid, as well as squamous cell carcinoma and carcinoid tumor of the lung. [ABSTRACT FROM AUTHOR]

Few comparisons have been made between low-aromaticity marine and lacustrine oil shales and their kerogens, because the reliability of structural analyses has been limited by a reliance on only one method of kerogen isolation, HCl-HF. Therefore, a detailed analysis by 13C NMR and X-ray photoelectron spectroscopy (XPS) was made for Attrat marine oil shale (Jordan) and Colorado (Green River) lacustrine oil shale (USA) and their NaOH-HCl kerogens. Some differences between oil shales and their kerogens were noted, but many structural features were considered to be true characteristics of the organic matter. The results emphasise the importance of comparing the analyses of kerogens isolated by different methods to ensure that features of the organic matter are not an artefact of the method of kerogen isolation. For both oil shales, the predominantly aliphatic character of the organic part was confirmed and the long average chain length of the aliphatic hydrocarbons was established. All shales and their kerogens showed a small cluster size for the aromatic rings. The elemental analysis obtained by XPS, compared with the bulk elemental analysis, indicated major differences between the near-surface region sampled by XPS and the bulk. The organic S was determined to be aliphatic and aromatic S with possibly small amounts of sulfoxide. Most of the N was pyrrolic with smaller amounts in pyridinic or quaternary form. Nearly all of the surface organic C in both kerogens was bonded to C and H. Two major forms of organic O were distinguishable. A good correlation between the proportion of aliphatic S and pyrolysis reactivity is suggested. This paper studies the comparison between low-aromaticity marine (Attrat-Jordan) and lacustrine (Colorado-USA) oil shales and their kerogens. Kerogens were extracted using NaOH-HCl method. The characterisations were performed using elemental analysis, Rock Eval, 13C NMR, and XPS. This work reveals some differences in the organic structure between the two kerogens. [ABSTRACT FROM AUTHOR]

DG-integrated distribution system planning is an imperative issue since the installing of distributed generations (DGs) has many effects on the network operation characteristics, which might cause significant impacts on the system performance. One of the most important characteristics that mostly varies because of the installation of DG units is the power losses. The parameters affecting the value of the power losses are number, location, capacity, and power factor of the DG units. In this paper, a new analytical approach is proposed for optimally installing DGs to minimize power loss in distribution networks. Different parameters of DG are considered and evaluated in order to achieve a high loss reduction in the electrical distribution networks. The algorithm of the proposed approach has been implemented using MATLAB software and has been tested and investigated on 12-bus, 33-bus, and 69-bus IEEE distribution test systems. The results show that the proposed approach can provide an accurate solution via simple algorithm without using exhaustive process of power flow computations. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Natural Sciences, Life & Applied Sciences is the property of Arab Journal of Sciences & Research Publishing (AJSRP) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

NMA,[6] also called mixed treatment comparison or multiple-treatments MA,[7] is an extension of the standard pairwise (A versus B) MA to a structure that includes multiple treatments (in the simplest example, A versus B versus C) and incorporates all the direct and indirect comparisons between the treatment arms, thus increasing precision while fully respecting randomization (Fig.). The solid arrow between them represents a pairwise meta-analysis (MA), which summarizes the effect estimate of treatment A compared to treatment B. Such methodology cannot simultaneously include a third available treatment C (Box 2), which has been compared to treatment A in other RCTs (A versus C trials), and would summarize this comparison separately (solid arrow). 2002; 21: 2313 - 24. 7 Salanti G. Indirect and mixed-treatment comparison, network, or multiple-treatments meta-analysis: many names, many benefits, many concerns for the next generation evidence synthesis tool. [Extracted from the article]

The oil shale (OS) sample from Sultani mine, southern Jordan, was subjected to thermogravimetric/differential thermogravimetric (TG/DTG) and differential scanning calorimetry (DSC) analysis. Analysis was used to determine the kinetic parameters in the 300-540 °C temperature range, employing different heating rates (3, 5, 10, 20, 30 °C/min). The first order conversion function was found to best represent the oil shale pyrolysis kinetics. The data in the studied pyrolysis temperature range was divided into three zones according to the behavior of the quantity ln(dx / dT /(1 x)) vs 1/T (K) . In the first linear zone, the apparent activation energy and frequency factor were found to be in the range of 63.1-94.2 kJ/mol and 9.3E+3-5.03E+6, respectively. In the second zone of analysis, the apparent activation energy was found to be negative and varied between -25.8 and -2.13 kJ/mol and the corresponding frequency factor was in the range of 19.65-0.00098. In the third zone under study, the calculated apparent activation energy and frequency factors were in the range of 186.9-342.1 kJ/mol and 1.87E+12-1.46E+23, respectively. [ABSTRACT FROM AUTHOR]

Copyright of Al-Rafadain Engineering Journal is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper describes the sensitivity of both the orbital frame domain selection and the gravity model on the performance of on-board real-time orbit determination. Practical error sources, which affect the navigation solution of spaceborne global positioning system (GPS) receivers, are analyzed first. Then, a reasonable orbital frame (radial, in-track, cross-track (RIC)) is proposed to clearly represent the characteristics of the error in order to improve the performance of the orbit determination (OD) logic. In addition, the sensitivity of the gravity model affecting the orbit determination logic is analyzed by comparison with the precise orbit ephemeris (POE) of the Challenging Minisatellite Payload (CHAMP) satellite, and it is confirmed that the Gravity Recovery And Climate Experiment (GRACE) Gravity Model 03 (GGM03) outperforms the Earth Gravity Model 1996 (EGM96). The effects of both proposed orbit frames and the gravity model on the orbit determination logic are verified using a GPS simulator and observation data from the CHAMP satellite. Moreover, the practical performance of on-board real-time orbit determination logic is verified by updating the software of the spaceborne GPS receiver, GPS-12, on DubaiSat-2 operating at low Earth orbit (LEO). The results show that the position accuracy of on-board real-time orbit determination logic in GPS-12 is improved by 59%, from 12.6 m (1 σ) to 5.1 m (1 σ), after applying the proposed methods. The velocity accuracy is also improved by 57%, from 13.7 mm/s (1 σ) to 5.9 mm/s (1 σ). [ABSTRACT FROM AUTHOR]