Because of their persistency and toxicity, dyes and heavy metal ions discharged to water bodies have become a worrisome issue.

We have synthesized graphene oxide using improved Hummer's method in order to explore the potential use of the resulting graphene oxide as a nanocarrier for an active anticancer agent, chlorogenic acid (CA). The synthesized graphene oxide and chlorogenic acid-graphene oxide nanocomposite (CAGO) were characterized using Fourier transform infrared (FTIR) spectroscopy, thermogravimetry and differential thermogravimetry analysis, Raman spectroscopy, powder X-ray diffraction (PXRD), UV-vis spectroscopy and high resolution transmission electron microscopy (HRTEM) techniques. The successful conjugation of chlorogenic acid onto graphene oxide through hydrogen bonding and π-π interaction was confirmed by Raman spectroscopy, FTIR analysis and X-ray diffraction patterns. The loading of CA in the nanohybrid was estimated to be around 13.1% by UV-vis spectroscopy. The release profiles showed favourable, sustained and pH-dependent release of CA from CAGO nanocomposite and conformed well to the pseudo-second order kinetic model. Furthermore, the designed anticancer nanohybrid was thermally more stable than its counterpart. The in vitro cytotoxicity results revealed insignificant toxicity effect towards normal cell line, with a viability of >80% even at higher concentration of 50μg/mL. Contrarily, CAGO nanocomposite revealed enhanced toxic effect towards evaluated cancer cell lines (HepG2 human liver hepatocellular carcinoma cell line, A549 human lung adenocarcinoma epithelial cell line, and HeLa human cervical cancer cell line) compared to its free form.

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In this present work, crystalline growth conditions of oriented carbon nanotubes based on chemical vapor deposition (CVD) were optimized. The crystallinity and degree of alignment of the grown carbon nanotubes (CNTs) were characterized by field emission scanning electron microscopy, transmission electron microscopy, and Raman spectroscopy. The effects of four variables, namely, deposition time, deposition temperature, annealing process, and concentration of the precursor on the crystallinity of the CNTs, were explored. Furthermore, the correlation of parameters with the growth mechanism was examined using response surface methodology in an attempt to determine the complex interactions between the variables. A total of 30 runs, including predicting and consolidation runs to confirm the results, were required for screening the effect of the parameters on the growth of the CNTs. On the basis of the investigated model, it was found that the crystallinity of the CNTs grown by the CVD method can be controlled via restriction of the effective parameters.

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Penyahsulfuranhidro (dirujuk sebagai HDS) dan penyaharomatikanhidro (dirujuk sebagai HDA) bagi Minyak Mentah Ringan telah dijalankan menggunakan pemangkin sulfida CoMo–S di dalam reaktor integral mangkin padat bertekanan tinggi. Kesan daripada parameter–parameter proses utama terhadap kualiti produk telah dikaji dengan mempelbagaikan suhu (200–370°C), tekanan (20 ke 50 bar) dan halaju ruang (1 hingga 4.7 h-1). Keputusan eksperimen menunjukkan, % aktiviti HDS dipertingkatkan sehingga 81% apabila suhu dinaikkan sehingga 370°C tetapi berkurang sehingga 60% dengan pertambahan halaju ruang sehingga 4.7 h-1. Selain itu, kputusan juga menunjukkan bahawa kadar % aktiviti HDA dipertingkatkan sehingga 40.6% apabila tekanan dinaikkan hingga mencecah 50 bar. Indeks setana menunjukkan peningkatan sebanyak 1–3 darjah dan graviti bertambah sehingga 1–1.7° API. Implikasi keputusan–keputusan ini terhadap industri penapisan adalah rawatan hidro sederhana terhadap bahan api diesel menggunakan teknologi tahap tunggal tidak memungkinkan loji penapisan tempatan menghasilkan bahan api yang memenuhi spesifikasi semasa (

In this work, the estimation capacity of the response surface methodology (RSM), in the catalytic naphtha reforming to enhance the octane number of reformats via isomerization reaction pathway and minimize the aromatization activity over tri-metallic modified Pt-Re/Al2O3 catalyst were investigated by applying Design of experiment (DOE). The parent bimetallic catalysts were modified using a relatively inactive metal (Sn) by means of employing non-conventional method of anchoring technique called controlled surface reaction (CSR) method in order to favor the intimate contact of Sn with the active phase to suppress the metallic character of Pt metal. The correlations between RON, aromatization and isomerization activities with three reaction variables namely temperature (480-510 o C), pressure (10-30 bar) and space velocity LHSV (1.2-1.8 h-1) were presented as empirical mathematical models via reforming of a complex mixture (80 o C-185 o C). Numerical results indicated that the minimum aromatization activity was 20% when reaction temperature was 460 o C and pressure of 35 bar. Results also show that maximum isomerization activity of 58% was achieved when pressure is 30 bar and space velocity is 1.8 h. it has been found that optimum value of RON = 89 was attained at 449.9 o C, 32 bar and 1.7 h-1. However, high operating pressure and low reaction temperature significantly decrease the aromatization activity coupled with substantial decrease in RON which can be enhanced by producing high yield of isomers.