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This paper aims to investigate and analyze the thermal performance of a double-pass solar air heater using multiple rectangular capsules filled with paraffin wax-based on a phase change material PCM. An indoor projector simulator was used to test a new system during the charge/discharge process. In order to verify the accuracy of these readings, a mathematical model based on finite-volume scheme SIMPLE algorithm was applied to solve the three-dimensional forced convection turbulent flow in the double-pass solar heater. The computational results were in reasonable agreement with the experimental readings. The investigations were carried out at various airflow speed of (0.6, 0.9, 1.2, 1.5, and 1.8) kg/min and three solar irradiance intensities of 625, 725, and 825 W/m2. The results showed that the increased airflow rate leads to delay in the melting period and decrease melting temperature of the paraffin during the melting period. Furthermore, it can be detected that the optimal discharging period and the air temperature rise of the heater were reached of: 3hr with (17.95–3) °C, 2 h with (14–3) °C, and 1.25 h with (11–2.5) °C, for various solar intensity of 825, 725, and 625 W/m2 at the same airflow speed of 0.6 kg/min, respectively.

Anethum sowa L. has been used as a spice herb in the Asian and European culinary systems to add flavour and taste. The studied plant has diverse folkloric medicinal value. Present study was designed to isolate phytochemicals from the hexane, chloroform and ethyl acetate extracts of the roots by various chromatographic techniques. Based on spectral analysis (IR, LC-MS, NMR) the isolated compounds were identified as physcione (1), β-sitosterol (2), stigmasterol (3), 2-oxo-3-propyl-2H-chromene-7-carboxylic acid (4), bergapten (5), 3-ethyl-7-hydroxy-2H-chromen-2-one (6) and graveolone (7). The mentioned compounds have been isolated for the first time from the roots part of the plant. Based on extensive literature review, physcione and bergapten were inferred to exhibit crucial bioactivities including inhibitory efficacy against various forms of cancer. Accordingly, in the present research approach molecular docking investigations of the isolated phytochemicals have been robustly executed with different oncogenes that have been reported to be actively involved in various forms of carcinoma. In silico investigations encompassing molecular docking analysis and drug-likeness profiling was executed to estimate the potential therapeutic tendencies of the phytochemicals targeted towards effective cancer therapy. Current investigation offers meaningful know-how pertaining to potential anticancer activities of the phytochemicals extracted from the roots of Anethum sowa L. and might open up new revenues towards effective drug development against cancer.

Ethnopharmacological relevance Arctotis arctotoides (Asteraceae) is part of the genus Arctotis. Arctotis is an African genus of approximately 70 species that occur widely in the African continent with diverse medicinal values. This plant is used for the treatment of indigestion and catarrh of the stomach, epilepsy, topical wounds and skin disorders among the ethnic groups in South Africa and reported to have a wide spectrum of pharmacological properties. Aim of the review The aim of the present review is to appraise the botany, traditional uses, phytochemistry, pharmacological potential, analytical methods and safety issues of A. arctotoides. Additionally, this review will help to fill the existing gaps in knowledge and highlight further research prospects in the field of phytochemistry and pharmacology. Materials and methods Information on A. arctotoides was collected from various resources, including books on African medicinal herbs and Zulu medicinal plants, theses, reports and the internet databases such as SciFinder, Google Scholar, Pubmed, Scopus, Web of Science, and Mendeley by using a combination of various meaningful keywords. This review surveys the available literature of the species from 1962 to April 2017. Results In vitro and in vivo studies of the medicinal properties of A. arctotoides were reviewed. The main isolated and identified compounds were reported as sesquiterpenes, farnesol derivatives, germacranolide, guaianolides and some steroids, of which, nine were reported as antimicrobial. Monoterpenoids and sesquiterpenoids were the predominant essential oil compound classes of the leaves, flowers, stems and roots. The present review revealed potential pharmacological properties such as anti-oxidant, antibacterial, antifungal and anticancer activities of plant extracts as well as isolated compounds. Moreover, the review reports the safety profile (toxicity) of the crude extracts that had been screened on brine shrimps, rats and human cell lines. Conclusions The present review has focused on the phytochemistry, botany, ethnopharmacology, biological activities and toxicological information of A. arctotoides. On the basis of reported data, A. arctotoides has emerged as a good source of natural medicine for the treatment of microbial infections, skin diseases, anti-inflammatory and anticancer agents and also provides new insights for further isolation of new bioactive compounds, especially the discovery of antimicrobial, anti-inflammatory and anticancer novel therapeutic lead drug molecules. Additionally, intensive investigations regarding pharmacological properties, safety assessment and efficacy with their mechanism of action could be future research interests before starting clinical trials for medicinal practices.

Ethnopharmacological relevance Anethum sowa Roxb. ex Fleming (Syn. Peucedanum sowa Roxb. ex Fleming, Family: Apiaceae) is a pharmacologically important as aromatic and medicinal plant. Various parts of this plant are used in traditional medicine systems for carminative, uterine and colic pain, digestion disorder, flatulence in babies, appetite-stimulating agent and used to treat mild flue and cough. The essential oil is used for aromatherapy. It is also used as a spice for food flavouring and culinary preparations in many Asian and European countries. Aim of the review This review aims to provide a comprehensive and critical assessment from the reported traditional and pharmaceutical uses and pharmacological activities of the extracts, essential oil and phytoconstituents with emphasis on its therapeutic potential as well as toxicological evaluation of A. sowa. Materials and methods Online search engines such as SciFinder®, GoogleScholar®, ResearchGate®, Web of Science®, Scopus®, PubMed and additional data from books, proceedings and local prints were searched using relevant keywords and terminologies related to A. sowa for critical analyses. Results The literature studies demonstrated that A. sowa possesses several ethnopharmacological activities, including pharmaceutical prescriptions, traditional applications, and spice in food preparations. The phytochemical investigation conducted on crude extracts has been characterized and identified various classes of compounds, including coumarins, anthraquinone, terpenoids, alkaloid, benzodioxoles, phenolics, polyphenols, phenolic and polyphenols, fatty acids, phthalides and carotenoids. The extracts and compounds from the different parts of A. sowa showed diverse in vitro and in vivo biological activities including antioxidant, antiviral, antibacterial, analgesic and anti-inflammatory, Alzheimer associating neuromodulatory, cytotoxic, anticancer, antidiabetes, insecticidal and larvicidal. Conclusion A. sowa is a valuable medicinal plant which is especially used in food flavouring and culinary preparations. This review summarized the pertinent information on A. sowa and its traditional and culinary uses, as well as potential pharmacological properties of essential oils, extracts and isolated compounds. The traditional uses of A. sowa are supported by in vitro/vivo pharmacological studies; however, further investigation on A. sowa should be focused on isolation and identification of more active compounds and establish the links between the traditional uses and reported pharmacological activities with active compounds, as well as structure-activity relationship and in vivo mechanistic studies before integrated into the medicine. The toxicological report confirmed its safety. Nonetheless, pharmacokinetic evaluation tests to validate its bioavailability should be encouraged.

Research has been undertaken on thermosyphon heat exchangers (THEs) for coolness recovery in sub-tropical climates conditions to explore the potential for energy savings and humidity control in HVAC systems through using THEs. This work includes an experimental and numerical model of THEs install in HVAC system. The performance of these individual systems was experimentally investigated throughout a wide range of outside design condition DBT (35–50) °C and RH (10–100)%. The outdoor tested parameters were the effect of RH, DBT, type of working fluid charged in THEs (Water, Methanol, Ethanol, Acetone, Butanol and R134a) and the air velocity. The experimental part involves a careful choose of the specification, design and construction of a THEs, an associates conventional chilled water coil, a fan and duct system, and a full range of properly calibrated sensors. The numerical model aims to develop a CFD model to define the flow characteristics (distribution of temperatures, moisture content and air velocity) for a THE in duct flow using momentum, turbulence model κ-e, moisture content and energy equations in 3D by using FORTRAN code to reach the better results to simulate accurately the influence of adding one or more THEs to the existing HVAC system. This indicates the importance of fully integrating the design process right from the outset of the system design if THEs are to be installed into a HVAC system so as to give the maximum possible energy saving benefits in efficient air handling unit (AHU) designs. On the basis of this study, it is recommended that subtropical HVAC systems should be installed with THEs for dehumidification enhancement (5–20%) and energy saving (5–35%).

Airborne γ radiometric and spectrometric surveys have shown that the Kab Amiri granite pluton is associated with an aero-γ anomaly of magnitude equivalent to about 4 backgrounds. Detailed field studies including γ spectrometric surveying, sampling, trenching and laboratory investigations revealed the following observations and conclusions. (1) The radioactive anomalies are associated with an episyenitized granite stock exposed to the south of the main pluton. (2) This western contact is controlled by a NW left-lateral major fault and its associated tension fracture systems. (3) The radioactive anomalous zones show many alteration features inclufing muscovitization, sericitization, ferrogenation and carbonatization. (4) The uranium contents range between 16–28 ppm in the non-altered granites, and between 44–169 ppm in the radioactive zones. The Th is very much depleted ranging 1–5.5 ppm with no distribution pattern. (5) The U-deposition is believed to epigenetic since it is associated with the muscovitized and carbonatized episyenite which represent later stages in the episyenitization process itself that is characterized by strong K-leaching.