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Highly active nitrogen-doped carbon xerogel (N-CX) electrocatalysts for the oxygen reduction reaction (ORR) were synthesized through a simple sol-gel method. The N-CX samples are prepared using resorcinol – formaldehyde resin as the carbon precursor and dicyandiamide as the nitrogen precursor. The N-CX samples carbonized at different temperatures are inspected to interpret the effect of the high-temperature conditions towards the structures and ORR activity of the final products. As-prepared N-CX samples with different carbonized temperatures are characterized via X-ray photoelectron spectroscopy (XPS), X-ray diffractometry and Raman spectroscopy. The N-CX sample carbonized at 800 °C demonstrated the greatest ORR activity, and the structural properties and catalytic activities of the catalyst are then further improved by insertion of cobalt metal under an ammonia atmosphere. Metal doping evidently promotes the catalytic activity of the N-CX catalyst. Raman and XPS studies show that cobalt increases the creation of pyridinic-N and quaternary-N groups through the formation of more graphitic structures. The ammonia atmosphere is demonstrated to act as an additional N source by increasing the total N content in the carbon structure after high temperature treatment of the N-CX catalyst. Metal-N-like and metal carbide configurations generated play a role in catalyst production with high catalytic activity.

Proton Exchange Membrane Fuel Cell (PEMFC) is powered by chemical reaction of oxygen gas with hydrogen gas as main fuel, to produce electricity and water, while operating at lower temperatures, which make it easy to operate and handle. PEMFC can power a large range of electrical equipment, from electronics devices to cars, buses, submarines as well as stationary power plants. This study presented the procedure of computational simulation and modelling of PEMFC with ANSYS Fluent. The geometry was designed with ANSYS design modeler, while meshing was performed in workbench meshing and solver in Fluent. For this study, two models with isothermal and non-isothermal conditions were considered. The isothermal condition is set at 323K and operated at 1 atm whereas the non-isothermal condition is set to operate at 353K and 3 atm. The voltage values were varying from 0.4V to 0.9V, where the open circuit voltage was set at 1.05V. The polarization curve of the PEMFC indicated the performance of the fuel cell, which also is the focus of this study. The effects of temperature and pressure towards the performance of the PEMFC were also studied and evaluated.

Agriculture waste has been used for the cultivation of commercial mushroom from historical years. Yet some limitations in producing efficient yield of the harvest especially for Volvariella volvacea cultivation remain unresolved. With different types of substrate used in the commercial farming of this mushroom, the biological efficiency of the mushroom is considered low compared to other species such as Lentinus sp., Pleurotus sp. and Agaricus sp. Thus, over the years, many attempts have been conducted to improve its biological efficiency using different approaches. In this brief review, major factors that limit the conversion of substrate to fruiting bodies will be discussed, while the current state-of-art for the cultivation practise for Volvariella volvacea will also be layout.

Chlorophyll and ternatin were extracted from Zingiber officinale leaves and Clitoria ternatea flowers respectively. These natural dyes were applied as sensitisers in TiO2-based dye-sensitised solar cells (DSSCs). Among 10 different solvents, the ethanol extracts revealed the highest absorption spectra of natural dyes extracted from Z. officinale and C. ternatea. A major effect of temperature increase was the increased extraction yield. High chlorophyll and ternatin yields were obtained under extraction temperatures of 80 °C and 70 °C, respectively. A notable decrease in C. ternatea dye concentration at temperatures >70 °C was also observed. High dye concentrations were obtained using acidic extraction solutions, particularly those with a pH value of 4. Experimental results showed that the DSSC fabricated with chlorophyll extracted from Z. officinale leaves exhibited a conversion efficiency of 0.30%, open-circuit voltage (Voc) of 0.56 V, short-circuit current (Isc) of 0.8 mA/cm−2 and fill factor (FF) of 57.93%. The DSSC sensitized with ternatin from C. ternatea flowers displayed a conversion efficiency of 0.13%, Voc of 0.54 V, Isc of 0.3 mA/cm−2 and FF of 81.82%.

Umbelliferon, the natural crenelated coumarin distributed in the plants of a piaceae family, has shown various biological activities, especially as a cancer chemo preventive agent. Coumarins have been categorized as a member of family of benzo-pyrone, that consist of pyrone ring united to benzene ring. The benzo-pyrones may be sectioned to alfa type that coumarins belong and the gama type that flavonoids have been major members. Coumarins are chemical entity which has being synthesized in the past few years many forms of its derivatives; the entity provides the principal origin of motivating to numerous chemist to investigate its diverse medical efforts especially with regards to the anticoagulant activity. In present article we review recent 4-Methylumbelliferon, (4-MU) that are synthesized with it pharmacological activities antioxidant, anti-inflammatory, antimicrobial activity, ant hepatitis, hepatoprotective, anticancer, antipyretic and analgesic activity. How to Cite this Article Pubmed Style Yasmeen Al-Majedy, Abdul Amir Kadhum, Hiba Ibraheem, Ahmed Al-Amiery, Ahmed Abdel Moneim, Abu Bakar Mohamad. A Systematic Review on Pharmacological Activities of 4-Methylumbelliferon. SRP. 2018; 9(1): 49-54. doi:10.5530/srp.2018.1.10 Web Style Yasmeen Al-Majedy, Abdul Amir Kadhum, Hiba Ibraheem, Ahmed Al-Amiery, Ahmed Abdel Moneim, Abu Bakar Mohamad. A Systematic Review on Pharmacological Activities of 4-Methylumbelliferon. http://www.sysrevpharm.org/?mno=302644548 [Access: March 28, 2021]. doi:10.5530/srp.2018.1.10 AMA (American Medical Association) Style Yasmeen Al-Majedy, Abdul Amir Kadhum, Hiba Ibraheem, Ahmed Al-Amiery, Ahmed Abdel Moneim, Abu Bakar Mohamad. A Systematic Review on Pharmacological Activities of 4-Methylumbelliferon. SRP. 2018; 9(1): 49-54. doi:10.5530/srp.2018.1.10 Vancouver/ICMJE Style Yasmeen Al-Majedy, Abdul Amir Kadhum, Hiba Ibraheem, Ahmed Al-Amiery, Ahmed Abdel Moneim, Abu Bakar Mohamad. A Systematic Review on Pharmacological Activities of 4-Methylumbelliferon. SRP. (2018), [cited March 28, 2021]; 9(1): 49-54. doi:10.5530/srp.2018.1.10 Harvard Style Yasmeen Al-Majedy, Abdul Amir Kadhum, Hiba Ibraheem, Ahmed Al-Amiery, Ahmed Abdel Moneim, Abu Bakar Mohamad (2018) A Systematic Review on Pharmacological Activities of 4-Methylumbelliferon. SRP, 9 (1), 49-54. doi:10.5530/srp.2018.1.10 Turabian Style Yasmeen Al-Majedy, Abdul Amir Kadhum, Hiba Ibraheem, Ahmed Al-Amiery, Ahmed Abdel Moneim, Abu Bakar Mohamad. 2018. A Systematic Review on Pharmacological Activities of 4-Methylumbelliferon. Systematic Reviews in Pharmacy, 9 (1), 49-54. doi:10.5530/srp.2018.1.10 Chicago Style Yasmeen Al-Majedy, Abdul Amir Kadhum, Hiba Ibraheem, Ahmed Al-Amiery, Ahmed Abdel Moneim, Abu Bakar Mohamad. "A Systematic Review on Pharmacological Activities of 4-Methylumbelliferon." Systematic Reviews in Pharmacy 9 (2018), 49-54. doi:10.5530/srp.2018.1.10 MLA (The Modern Language Association) Style Yasmeen Al-Majedy, Abdul Amir Kadhum, Hiba Ibraheem, Ahmed Al-Amiery, Ahmed Abdel Moneim, Abu Bakar Mohamad. "A Systematic Review on Pharmacological Activities of 4-Methylumbelliferon." Systematic Reviews in Pharmacy 9.1 (2018), 49-54. Print. doi:10.5530/srp.2018.1.10 APA (American Psychological Association) Style Yasmeen Al-Majedy, Abdul Amir Kadhum, Hiba Ibraheem, Ahmed Al-Amiery, Ahmed Abdel Moneim, Abu Bakar Mohamad (2018) A Systematic Review on Pharmacological Activities of 4-Methylumbelliferon. Systematic Reviews in Pharmacy, 9 (1), 49-54. doi:10.5530/srp.2018.1.10

In this study, cobalt-doped carbon xerogel (Co-CX) was synthesised via sol-gel polymerisation of phenolic compounds (i.e., resorcinol, phenol and m-cresol) and formaldehyde, and this polymerisation was catalysed by cobalt nitrate and followed by a carbonisation process. The effect of the initial pH value (5.5, 6.5 and 7.5) as well as the type of carbon precursors on the structural properties of Co-CX was investigated via field emission scanning electron microscope (FESEM), Brunauer-Emmett-Teller (BET) and X-ray diffractometry (XRD). The catalytic activity of Co-CX for the oxygen reduction reaction (ORR) in 0.1 M KOH was studied using a rotating ring-disk electrode (RRDE) technique. The structural properties and ORR activities were affected by different initial pH values as well as the type of carbon precursor. A carbon precursor consisting of resorcinol-formaldehyde with an initial pH value of 7.5 exhibited the best catalytic activity. The initial pH plays an important role in promoting micro/mesopores. The FESEM and BET results revealed that Co doping promotes the formation of additional pores. The RRDE result indicated that Co-CX exhibited good catalytic activity that tends to favour a four-electron pathway.

Cu-Zn-V-Al oxide composite catalysts were prepared using a co-precipitation method to investigate hydrogen and carbon monoxide yield of a methanol reforming reaction. The mass compositions of metals were initially determined on the Simplex Centroid statistical design. The effects of various metal compositions on the physicochemical properties of the catalyst were studied via X-ray diffractogram (XRD), temperature-programmed reduction (TPR) analyses, and reaction. XRD revealed crystals in the samples. Crystalline CuO in Cu30V30Al40 formed with the addition of zinc oxide at the metal loading below 30 wt%. A combination of zinc oxide and vanadia, however, had no Zn-V complex crystal but its scanning electron microscopy image showed the formation of string structures (AS). The catalyst that contained the AS exhibited a broad hydrogen reduction peak in the TPR analysis. Vanadium at a loading below 40 wt% with various zinc and cuprum compositions also formed small ASs and exhibited single TPR peaks. A reaction yield study revealed the optimum compositions of metal oxides when the data was fitted by response surface plots. The catalysts with high content of AS were not at the peaks however. Cu-Zn based catalysts showed the highest hydrogen yield for the reaction temperature of between 150 oC to 225 oC and vanadia-promoted catalyst with AS only appeared to be the optimum catalyst at the higher temperature. ABSTRAK: Mangkin komposit oksida Cu-Zn-V-Al disediakan menggunakan kaedah pemendakan bersama untuk mengkaji hasil hidrogen dan karbon monoksida daripada tindak balas pembentukan semula metanol. Komposisi jisim logam-logam dikenal pasti terlebih dahulu menggunakan reka bentuk statistik Simplex Centroid. Pelbagai kesan komposisi logam terhadap sifat-sifat mangkin kimia-fizikal dikaji menerusi analisis-analisis pembelauan sinar-X (XRD) dan program penurunan suhu teratur (TPR), dan tindak balas kimia. Hasil analisis XRD menzahirkan kristal pada sampel-sampel. Hablur CuO terbentuk dalam Cu30V30Al40 dengan penambahan zink oksida pada muatan logam kurang daripada 30% berat. Gabungan zink oksida dan vanadia walau bagaimanapun tidak menghasilkan hablur kompleks Zn-V, namun imbasan imej mikroskop elektron menunjukkan pembentukan struktur tetali (AS). Mangkin yang mengandungi AS menunjukkan penurunan puncak hidrogen yang lebar dalam analisis TPR. Vanadium pada muatan berat logam kurang daripada 40% berbanding komposisi zink dan kuprum juga membentuk AS kecil dan menghasilkan puncak-puncak TPR tunggal. Hasil tindak balas kajian menunjukkan komposisi optimum oksida logam apabila data ujikaji dipadankan dengan menggunakan plot permukaan respon. Mangkin yang mempunyai kandungan AS tertinggi bagaimanapun tidak berada pada puncak. Mangkin berasaskan Cu-Zn menunjukkan hasil hidrogen tertinggi bagi suhu tindak balas antara 150 oC hingga 225 oC dan mangkin yang ditambah vanadia bersama AS pula muncul sebagai mangkin optimum pada suhu lebih tinggi.

The natural dyes anthocyanin and chlorophyll were extracted from Musa acuminata bracts and Alternanthera dentata leaves, respectively. The dyes were then applied as sensitizers in TiO2-based dye-sensitized solar cells (DSSCs). The ethanol extracts of the dyes had maximum absorbance. High dye yields were obtained under extraction temperatures of 70 to 80°C, and the optimal extraction temperature was approximately 80°C. Moreover, dye concentration sharply decreased under extraction temperatures that exceeded 80°C. High dye concentrations were obtained using acidic extraction solutions, particularly those with a pH value of 4. The DSSC fabricated with anthocyanin from M. acuminata bracts had a conversion efficiency of 0.31%, short-circuit current (Isc) of 0.9mA/cm2, open-circuit voltage (Voc) of 0.58V, and fill factor (FF) of 62.22%. The DSSC sensitized with chlorophyll from A. dentata leaves had a conversion efficiency of 0.13%, Isc of 0.4mA/cm-2,Voc of 0.54V, and FF of 67.5%. The DSSC sensitized with anthocyanin from M. acuminata bracts had a maximum incident photon-to-current conversion efficiency of 42%, which was higher than that of the DSSC sensitized with chlorophyll from A. dentata leaves (23%). Anthocyanin from M. acuminata bracts exhibited the best photosensitization effects.

Plasticisers have been widely used as additives in polymer applications, including pharmaceuticals, food processing, and electrochemical sensing, to improve the mechanical and physicochemical properties of the polymers. Recent developments using alternatives to the conventional phthalate ester plasticisers, such as water, ionic liquids (ILs) and deep eutectic solvents (DES), have opened new avenues for expanding plasticiser use into other potential areas such as ion exchange membranes. Owing to the unique properties of plasticisers that promote a higher amount of amorphous phase within the intermolecular structural of the polymer, combinations of plasticisers and polymers improve a polymeric film's ionic conductivity while maintaining film flexibility and thermal stability. Hence, this review paper intends to provide an insight on the applications of conventional and alternative plasticisers in various areas, as well as to address the working mechanism of plasticisers within polymer films. Most importantly, this paper highlights recent developments incorporating plasticisers in proton exchange membranes and the future potential of these materials. The outlook presented here demonstrates that some of the challenges faced during the fabrication of ion exchange membranes, which are alternatives to Nafion membranes, can be overcome.

Inhibitors are synthetic and natural molecules have various functional groups like double or triple bonds and heteroatoms; N, O or S, which permit adsorption onto the MS (metal surface). These inhibitors have the ability to adsorb onto the MS and block the active site that was reducing the corrosion rate. Inhibition efficiencies of the investigated compounds: Sulfacetamide (SAM), Sulfamerazine (SMR), Sulfapyridine (SPY) and Sulfathiazole (STI), as inhibitors in corrosive solution were evaluated based on weight loss technique. Nitro and Amino groups were chosen for the study of the substituted reaction of four corrosion inhibitor compounds: SAM, SMR, SPY and STI, theoretically utilizing the thickness capacities hypothesis DFT (density functions theory) method with the level [rB3LYP/6-311G(d,p)]. Our research demonstrated that the nitration of studied molecules lead to a diminishing in inhibition efficiencies, group lead to an increase in inhibition efficiency. Compared with corrosion inhibitor molecules these results gave a significant improvement in inhibition efficiency for corrosion inhibitor molecules.

Emergence of resistance by bacterial and fungal stains towards existing antimicrobial agents is one of the major problem as well as motivation to synthesize a new class of antimicrobial agents possessing potent ac-tivity compared to commonly used therapy. Coumarin is the heterocyclic compound formed from benzene and pyrone ring containing oxygen and its derivatives are of wide awareness because of their diverse biological activity and clinical applications, they are remarkably effective compounds both with respect to their inhibitory activity and their favourable selectivity ratio. Coumarins are regarded as a promising class of bioactive heterocyclic compounds that exhibit a range of biological activities like anti-microbial, anti-viral, anti-diabetic, anti-cancer activity, anti-oxidant, anti-parasitic, anti-helmintic, anti-proliferative, anti-convulsant, anti-inflammatory and anti-hy-pertensive activities etc. The information given in this manuscript may be helpful in the further research of better antimicrobial agents having lesser microbial resistance and improved antimicrobial profile. How to Cite this Article Pubmed Style Yasameen K. Al-Majedy, Abdul Amir H. Kadhum, Ahmed A. Al-Amiery, Abu Bakar Mohamad. Coumarins: The Antimicrobial agents. SRP. 2017; 8(1): 62-70. doi:10.5530/srp.2017.1.11 Web Style Yasameen K. Al-Majedy, Abdul Amir H. Kadhum, Ahmed A. Al-Amiery, Abu Bakar Mohamad. Coumarins: The Antimicrobial agents. http://www.sysrevpharm.org/?mno=302644565 [Access: March 28, 2021]. doi:10.5530/srp.2017.1.11 AMA (American Medical Association) Style Yasameen K. Al-Majedy, Abdul Amir H. Kadhum, Ahmed A. Al-Amiery, Abu Bakar Mohamad. Coumarins: The Antimicrobial agents. SRP. 2017; 8(1): 62-70. doi:10.5530/srp.2017.1.11 Vancouver/ICMJE Style Yasameen K. Al-Majedy, Abdul Amir H. Kadhum, Ahmed A. Al-Amiery, Abu Bakar Mohamad. Coumarins: The Antimicrobial agents. SRP. (2017), [cited March 28, 2021]; 8(1): 62-70. doi:10.5530/srp.2017.1.11 Harvard Style Yasameen K. Al-Majedy, Abdul Amir H. Kadhum, Ahmed A. Al-Amiery, Abu Bakar Mohamad (2017) Coumarins: The Antimicrobial agents. SRP, 8 (1), 62-70. doi:10.5530/srp.2017.1.11 Turabian Style Yasameen K. Al-Majedy, Abdul Amir H. Kadhum, Ahmed A. Al-Amiery, Abu Bakar Mohamad. 2017. Coumarins: The Antimicrobial agents. Systematic Reviews in Pharmacy, 8 (1), 62-70. doi:10.5530/srp.2017.1.11 Chicago Style Yasameen K. Al-Majedy, Abdul Amir H. Kadhum, Ahmed A. Al-Amiery, Abu Bakar Mohamad. "Coumarins: The Antimicrobial agents." Systematic Reviews in Pharmacy 8 (2017), 62-70. doi:10.5530/srp.2017.1.11 MLA (The Modern Language Association) Style Yasameen K. Al-Majedy, Abdul Amir H. Kadhum, Ahmed A. Al-Amiery, Abu Bakar Mohamad. "Coumarins: The Antimicrobial agents." Systematic Reviews in Pharmacy 8.1 (2017), 62-70. Print. doi:10.5530/srp.2017.1.11 APA (American Psychological Association) Style Yasameen K. Al-Majedy, Abdul Amir H. Kadhum, Ahmed A. Al-Amiery, Abu Bakar Mohamad (2017) Coumarins: The Antimicrobial agents. Systematic Reviews in Pharmacy, 8 (1), 62-70. doi:10.5530/srp.2017.1.11

Nitrogen-doped carbon materials have great potential as metal-free catalysts in a variety of applications, including batteries, supercapacitors and fuel cells. In this paper, nitrogen-doped graphene (NG) catalysts were synthesized via thermal annealing with varying ratios of graphite oxide and melamine precursors. The NG catalysts were characterized by transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The prepared NG catalysts were folded transparent films with wrinkles. The nitrogen content of the NG catalysts calculated from XPS varied from approximately 4.18%–7.40%. NG1 displayed the highest performance, with a remarkable reduction peak of 0.39 mA cm−2 at −0.21 V vs. Ag/AgCl in alkaline media. A direct correlation between total nitrogen content and catalytic activity was not observed, but catalytic activity was dependent on the nature of the nitrogen configurations. XPS analysis revealed that the high catalytic activity of NG1 is attributable to the configuration of the graphitic N-type nitrogen.

This research involves the rare utilisation of the kapok fibre (Ceiba pentandra) as a raw material for the fabrication of cellulose nanocrystal (CNC) and self-assembled CNC membranes. The isolation of CNC from Ceiba pentandra began with the extraction of cellulose via the chemical alkali extraction by using 5wt% NaOH, followed by the typical acidified bleaching method and, finally, the CNC production through acid hydrolysis with 60wt% H2SO4 at the optimum time of 60min. The prepared CNC was then employed for the preparation of self-assembled membrane through the water suspension casting evaporation technique. The obtained CNC membrane was characterised in terms of its composition, crystallinity, thermal stability, as well as, structural and morphological features with the use of several techniques including FTIR, XRD, AFM, TEM, FESEM, and TGA. The FESEM and AFM analyses had illustrated the achievement of a self-assembled CNC membrane with a smooth surface and a well-distributed nano-porous structure, with the porosity of 52.82±7.79%. In addition, the findings proved that the self-assembled CNC membrane displayed good adsorption capability indicated by the recorded efficiency of 79% and 85% for 10mg/L and 5mg/L of methylene blue in an aqueous solution, respectively.

The effect of adding silica (SiO2) to a mixed-salt solid acid composite, CsH2PO4/NaH2PO4, was studied via conductivity measurements, thermal analyses and X-ray diffraction. The conductivity value of the composites ranged from 1.1 × 10−4 S cm−1 to 7.6 × 10−3 S cm−1 for temperatures from 210 °C to 250 °C, respectively. Adding NaH2PO4 to the composite reduced the conductivity value at 230 °C due to the decomposition of NaH2PO4, which initiated at 210 °C. Dehydration of CsH2PO4 was evident at 230 °C and 270 °C, while the superprotonic phase transition was not observed. Dehydration was detected for NaH2PO4 at temperatures above 210 °C, but a thermally stable composite was produced by mixing it with CsH2PO4 and SiO2. An X-ray diffraction analysis confirmed the existence of solid acid solutions for the composites consisting of NaH2PO4:CsH2PO4 and SiO2:CsH2PO4 in molar ratios of 1:10 to 3:10. The presence of SiO2 partially obstructed the dehydration of the composite, as the diffraction intensity of the dehydration by-product Cs2H2P2O7 decreased at the end of the thermal treatment.

2-Methyl-4H-benzo[d][1,3]oxazin-4-one (BZ1) and 3-amino-2-methylquinazolin-4(3H)-one (BZ2) were evaluated for their corrosion inhibition properties on mild steel (MS) in hydrochloric acid solution by weight loss technique and scanning electron microscopy. Results show the inhibition efficiency values depend on the amount of nitrogen in the inhibitor, the inhibitor concentration and the inhibitor molecular weight with maximum inhibition efficiency of 89% and 65% for BZ2 and BZ1 at highest concentration of the compounds. Keywords: Methylquinazoline, Benzoxazines, Corrosion, Inhibitors