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Sichuan Basin (SCB) is a typical basin in southwest China and a traditional smog-prone area. Control of air pollution in this area is particularly critical in achieving China’s carbon emission peak and carbon neutral goals. It is characterized by high population density, heavy transportation, rapid industrialization, complex topography, and meteorological conditions. However, the air pollution studies of SCB remain the sparse and in-depth studies are still warranted. None of the previous research has synthetically reviewed the status of air pollution in this region. This paper comprehensively overviewed the air pollution of SCB from five aspects: air pollution characteristics, sources of air pollutants, driving factors of air pollution, air pollution episodes and health risks. A comparison on the air pollution of typical megacities in the basin was also discussed. The findings and shortcomings of the existing studies were also summarized. Recommendations for future research directions were also proposed.

Lipids and eicosapentaenoic acid (EPA) compounds from Nannochloropsis oceanica biomass were extracted using a combination of ionic liquids (ILs) and microwave-assisted extraction (MAE). When compared to conventional Soxhlet extraction, the proposed novel approach in this paper successfully improved both the yield of total extracted lipids and the EPA content. The effect of selected extraction parameters including the weight of applied IL (tetramethyl ammonium chloride: [TMAm][Cl]) (0.5–2.5 g), reaction temperature (60–100 °C), and process time (5–30 min) on final products was evaluated using response surface methodology (RSM). The optimal values of parameters were determined and three-dimensional response surfaces were plotted from the mathematical models and discussed. The yield of total extracted lipids and the content of EPA were found 19.58 wt% (g g−1 of total biomass) and 37.919 mg g−1 of total FAME respectively, when the extraction process was accomplished in 24.69 min at 88.18 °C and with 1.65 g of ILs. Analysis of variance (ANOVA) was applied in the analysis of experimental data and the R2 of 0.9506 and 0.9517 for total lipid and EPA models, respectively, show that the experimental findings were well aligned with the predicted values. Furthermore, at similar condition, the extraction process was replicated using two other types of ILs namely [EMIM][Cl] and [EMPyrro][Br] to extract the total lipid and EPA. The results showed that [TMAm][Cl] performed better in extracting compounds from microalgae. Based on the findings, this study shows that the combination of ILs mediated in water-based MAE is an environmentally friendly, reliable, and efficacious approach to enhance the extraction of lipids and EPA from N. oceanica with considerable potential to be up-scaled for commercial applications.

The functionalized graphene oxide by silica and chitosan helped to prepared an adsorbent with high adsorption potential for removing cadmium(II). In this study, the adsorbent was synthesized and the batch system of adsorption method was examined to find the potential of the new adsorbent with the various factors of the concentration, pH, time and temperature. The characterization of adsorbent was analyzed by FT-IR, TEM, Zeta potential and XRD analysis. Regards to the analysis it can be understood that the adsorbent was synthesized successfully. The investigational results were validated and analyzed by applying the 5 models of isotherm and 4 models of kinetic. The Langmuir, Freundlich, Temkin, Harkins-Jura and Dubinin-radushkevich models were used which the Langmuir, Freundlich and Temkin fitted well for removing cadmium(II). The Q(max) value was achieved 126.58 mg/g by using the Langmuir model for removing Cd(II) respectively. The pseudo-first-order, pseudo-second-order, Elovich and Intra-particle models were used to validate the kinetic models of the process. The pseudo-second-order and Elovich models were the best fitted kinetic model in this investigation. Thermodynamic parameters of the energy of gibes, the enthalpy, and the entropy were calculated. Generally, the adsorption process was distinguished as an exothermic and spontaneous.

The mass loss against temperature and time through thermogravimetry analysis (TGA) was measured upon six wood species: Shorea laevis (Balau), Vatica rassak (Resak), Koompassia malaccensis (Kempas), Heritiera albiflora (Mengkulang), Shorea parvifolia (Meranti sarang punai), and Cratoxylum arborescens (Geronggang) at the heating rates of 5, 10, and 20 °C/min in a nitrogen environment. These species have shown three stages of thermal decomposition, including the dehydration stage, the active stage, and the passive stage. The thermal decomposition curves exposed that the hemicellulose and cellulose were actively pyrolyzed during the second-stage of the pyrolysis (active stage). In contrast, the decomposition of lignin happens at a slower pace in both the second and third-stage (passive stage). The maximum decomposition peak in the derivative thermogravimetric (DTG) curves for every species moved to a higher temperature range following the acceleration in heating rates. The kinetic decomposition parameters of the woods were identified by embracing the thermal kinetic method of Coats and Redfern (CR). The higher activation energy (Ea) in the second-stage demonstrates that the corresponding species consists of more cellulose compared to others. Furthermore, all species showed lower Ea during the third-stage of pyrolysis involving lignin content. The pre-exponential factor (A) for all species disclosed a relative connection to the Ea; the higher the Ea, the higher the value of A.

The main purpose of the study was to enhance the stability and therapeutic effects of Curcumin (Cur) through nanoformulation with gum Arabic (GA) as a coating agent through an efficient synthetic approach. The antioxidant properties of the developed nanoparticles (Cur/GANPs) were assessed through several in vitro assays, such as β-carotene bleaching activity, DPPH, and nitric oxide scavenging activities in addition to evaluating its inhibitory activity on angiotensin-converting enzyme (ACE). The cytotoxicity of Cur/GANPs was evaluated in vitro using different types of human cancer cells including breast cancer (MCF7, MDA-MB231), liver cancer (HepG2), and colon cancer (HT29) cells. The prepared particles displayed an elliptical shape with a size ranging between 20–260 nm and a potential difference of –15 mV. The Cur/GANPs exhibited significant antioxidant activity compared to free curcumin when using concentrations between 31.5 and 500 µg/mL. The Cur/GANPs also had inhibited the growth of all cancer cell lines in a proportional trend with concentrations used. Hence, the encapsulation with gum Arabic has augmented the antioxidant and anti-neoplastic effects of Curcumin. Therefore, Cur/GANPs may have effective therapeutic properties in diseases attributed to oxidative stress like cancer and hypertension.

Microalgae are an alternative source of renewable energy and high-value products for pharmaceutical, nutraceutical, etc., due to rich in carbohydrates, proteins, lipids, and high-density lipoproteins. Existing methods for cell disruption and extraction are costly and suffered from low proficiencies. Ionic liquids are proven to be an environmentally friendly substitute to conventional volatile organic solvents. They have been used in extracting different types of biomass, including microalgae. This article reviews the potential of ILs in extracting biomolecules, lipid, and omega-3, from microalgae biomass. The physicochemical properties of ILs, including viscosity, density, and melting point, their advantages and limitation, as well as toxicity and recyclability of ILs in lipid processing, are discussed.

The flow rate or fluid velocity measurement is important to maintain fluid flow quality performance in the systems. This study focuses on determination of volumetric flow rate measurement and to calibrate the conventional flowmeter using industrial radiotracer approach in quadrilateral gas-liquid bubble column reactor. In this work, two different radioisotopes which emit γ-ray have been chosen as radioactive tracer which is 99mTc produced from 99Mo/99mTc radioisotope generator and 198Au nanoparticle form neutron activation at research nuclear reactor TRIGA Mark II. Both radioisotopes representing liquid and solid tracer purposely designed for tracing liquid flow. The peak to peak radiotracer method known as pulse velocity method was applied to determine the volumetric flow rate. The radiation signals were monitored using 4 unit NaI scintillation detectors located at 4 different points nearby the inlet and outlet of the quadrilateral bubble column reactor process stream. The water volume inside the bubble column reactor was fixed at 0.04 m3 and liquid flow rates in this reactor were specified on installed flowmeter at different reference value which is 4 lpm, 8 lpm, and 12 lpm, respectively. The experimental result shows very good linearity and repeatability by following the theoretical equations with less uncertainty in volumetric flow rate measurement. The obtained results also validated the effectiveness of the proposed method for the installed flowmeter calibration efficiency.

Accidents involving higher learning institutes laboratories are no longer a worldwide issue. There is a huge gap between how safety is practiced in industry compared to how it is practiced in research laboratories, especially in an academic setting. For effective implementation of the safety management system, it is necessary to have a strong and positive safety culture throughout the organization. The investigation to the safety culture (SC) practices level and performances among laboratory’s users in the Faculty of Engineering, Universiti Putra Malaysia will be assessed, evaluated and recommended some of the improvement towards SC in UPM. The assessment is done through the distribution of safety culture questionnaire adapted from Hudson’s safety culture element and a publication by American Chemical Society and the results will be based on rating distribution. The safety culture survey resulted in an overall score of µ=3.98 (µ

Curcumin nanoparticles (Cur/GANPs) were formulated based on gum arabic (GA) as a stabilizer coatings for nanoparticles through efficient synthesis approach. The current study investigated the antioxidant properties and antihypertensive activity of curcumin (Cur) using various established in vitro assays, such as 1,1-diphenyl-2-picrylhydrazyl (DPPH) as well as angiotensin converting enzyme (ACE) inhibitory activity. The in vitro cytotoxicity of Cur/GANPs against human liver cancer (HepG2), and colon cancer (HT29) was investigated. The exposure of human cancer cells to Cur/GANPs (1.56-100 µg/ml) using MTT (3-(4,5-dimethylthiazol-2-yl) 2,5-diphenyl tetrazolium bromide) has revealed that the Cur/GANPs inhibited the growth of cell lines examined in a dose dependent manner. Hence, Cur/GANPs nanoparticles may have great potential to be applied for cancer treatment. The authors would like to acknowledge International Islamic University Malaysia and Universiti Putra Malaysia for awarding the funds to conduct this research under project number of P-RIGS18-026-0026 and GP-IPS/2016/9505500

Maintenance is one of the important roles in the high technology manufacturing industry. It is related to the key performance factors of the company such as quality, productivity, and cost. To achieve these factors, a reliability plan should be implemented which helps to maximise production value by implementing successful asset maintenance. This research project aims to focus on the critical process equipment known as Horizontal Wet Etching Equipment (HWEE) used in the wet etching process. The components in the HWEE system were identified by referring to the process and instrumentation diagram (PID) of the equipment and were categorised in different modes. Data on mean time to repair (MTTR) and mean time between repairs (MTBF) were collected based on previous company records. The data were analysed using MAROS software. Failure Mode and Effect Analysis (FMEA) was done to understand the risk of each of the components. The result shows that piping and gearbox have the highest RPN with 126 and 105, respectively. This study helps to identify critical components and is able to help the company to improve equipment reliability and reduce maintenance cost. Corrective action can be implemented to reduce the RPN for both components. Thus, it would help the industry to increase the key performance and become more competitive in the business environment.

Gallic acid (GA) is a natural phenolic compound with therapeutic effects that are often challenged by its rapid metabolism and clearance. Therefore, GA was encapsulated using gum arabic into nanoparticles to increase its bioavailability. The formulated nanoparticles (GANPs) were characterized for physicochemical properties and size and were then evaluated for antioxidant and antihypertensive effects using various established in vitro assays, including 1,1-diphenyl-2-picrylhydrazyl (DPPH), nitric oxide scavenging (NO), β-carotene bleaching and angiotensin-converting enzyme (ACE) inhibitory assays. The GANPs were further evaluated for the in vitro cytotoxicity, cell uptake and cell migration in four types of human cancer cell lines including (MCF-7, MDA-MB231) breast adenocarcinoma, HepG2 hepatocellular cancer, HT-29 colorectal adenocarcinoma, and MCF-10A breast epithelial cell lines. The GANPs demonstrated potent antioxidant effects and have shown promising anti-cancer properties in a dose-dependent manner with a predilection toward HepG2 and MCF7 cancer cells. The uptake of GANPs was successful in the majority of cancer cells with a propensity to accumulate in the nuclear region of the cells. The HepG2 and MCF7 cancer cells also had a significantly higher percentage of apoptosis and were more sensitive to gallic acid nanoparticle treatment in the cell migration assay. This study is the first to confirm the synergistic effects of gum arabic in the encapsulation of gallic acid by increasing the selectivity towards cancer cells and enhancing the antioxidant properties. The formulated nanoparticles also had remarkably low toxicity in normal cells. Based on these findings, GANPs may have promising therapeutic applications towards the development of more effective treatments with a probable targeting precision in cancer cells.

This paper aimed to review the research on emulsion formation, stability, chemical demulsification, and hydrophilic–lipophilic balance in chemical studies and other aspects related to emulsion thermodynamics. The global increase in energy demand pressures oil and gas producers to develop and explore a new source of energy. Crude oil is one of the indispensable sources produced from unconventional and conventional resources. It is accompanied by high water content during production activities, and this water is complex and has a high content of contaminants. This water is also produced in the form of foam or emulsion. Water-in-oil emulsion is considered as a common type in petroleum industry. Oil emulsion is very harmful due to the associated difficulties during the refining and transportation of crude oil and the limitation in the produced water discharge. The emulsion in petroleum industry is stable due to the natural surface-active compounds in crude oil. Thus, oilfield researchers need to study different utilization methods to demulsify emulsion. Chemical method is considered as an essential method in treating petroleum emulsion by using demulsifiers, such as non-ionic surfactant.

Heavy metal ions have a toxic and negative influences on the environment and human health even at low concentrations and need to be removed from wastewater. Chitosan and graphene oxide are suitable nano plate adsorbents with high adsorption potential because of their &pi, &pi, interaction, and they are available functional groups that interact with other elements. In this study, graphene oxide was coated with silica to enhance the hydrophilicity of the adsorbent. Subsequently, the adsorbent was functionalised by various amounts of chitosan to improve the Pb(II) removal. The adsorbent was analysed using transmission electron microscopy (TEM), Raman, Fourier-transform infrared spectroscopy (FT-IR), scanning electron microscope (SEM), and mapping analysis techniques. An investigation of the influences of the initial concentration of Pb(II), pH and contact time were included to obtain the optimum amount of adsorption. The range of the initial Pb(II) concentration studied was from 10 to 120 mg/L. The pH factor ranged from 3 to 8 with contact time from 0 to 140 min. Freundlich, Temkin and Langmuir isotherm models were fit to the results, and a pseudo-second-order kinetic model was found to provide a good fit as well. The maximum Pb(II) removal capacity achieved was 256.41 (+/&minus, 4%) mg/g based on Langmuir isotherms.

This study performs a screening of potential Ionic Liquids (ILs) for the extraction of Docosahexaenoic Acid (DHA) compounds by the calculation of capacity values. For this purpose, a Conductor-Like Screening Model for Real Solvents (COSMO-RS) was employed to study the molecular structures of the ILs, and therefore, predict their extraction potential. The capacity values of 22 anions combined with 16 cations based ILs, were investigated to evaluate the effectiveness of ILs in the extraction of DHA. It was found that among the investigated ILs, a combination of tetramethyl ammonium with SO4 or Cl was the best fit for DHA extraction, followed by pyrrolidinium, imidazolium, pyridinium and piperidinium. Furthermore, it was observed that the extraction capacity and the selectivity of ILs decreased with an increase in alkyl chain length, therefore, ethyl chain-ILs, with the shortest chain lengths, were found to be most suitable for DHA extraction. The predicted results were validated through the experimentally calculated extraction yield of a DHA compound from Nannochloropsis sp. Microalgae. Five selected ILs, namely [EMIM][Cl], [BMIM][Cl], [TMAm][Cl], [EMPyr][Br] and [EMPyrro][Br], were selected from COSMO-RS for empirical extraction purposes, and the validation results pinpointed the good prediction capabilities of COSMO-RS. The findings in this study can simplify the process of selecting suitable ILs for DHA extraction and reduce the number of required empirical evaluations.

Background: Polymeric inclusion complex has been used frequently as a drug delivery system due to controlled release, non-toxic properties and high bioavailability. Objective: The current study aims to improve drug release properties of orotic acid loaded with chitosan inclusion complex (OA/CS). Material and methods: The OA/CS inclusion complex were synthesized using freeze drying technique. The characterization of inclusion OA/CS was carried out using Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffractometry (XRD), Differential Scanning Calorimetry (DSC), Zeta sizer, and Transmission Electron Microscopy (TEM). Results: The FTIR peaks of orotic acid have almost vanished in the OA/CS spectrum due to the restriction of OA vibration upon loading in CS cavity. The diffraction peaks of the OA/CS are completely diffused due to the amorphous state and the lack of crystallinity of inclusion complex. The DSC marked changes are indicative of the amorphous phase of solid dispersion, as well OA encapsulation into the nanocavity of CS. The size of OA/CS ranged between 58 nm and 200 nm and the zeta potential was 30 mV. In addition, transmission electron microscopy (TEM) showed that OA/CS sizes were ranged from 20 to 45 nm. Conclusion: Thus, this study indicates that OA/CS has promising future to further develop a carrier for drug delivery systems.

Fuel resource diversification is a global effort to deviate from non-renewable fossil fuels. Biomass has been identified as an alternative solid biofuel source due to its desirable properties and carbon neutrality. As reported in the literature, biomass can positively contribute towards combating climate change while providing alleviation for energy security issue. As part of efforts to diversify biomass resources, this work intends to explore the potential of Napier grass, one type of energy crop, for the production of renewable syngas via gasification. This energy crop is originally from Africa, which is highly productive with low cost (40 tonnes per year per hectare). Limited studies were conducted to analyze the potential of such an energy crop as a fuel source, which is the subject of this work. In order to analyze the full potential of such energy crop, the physical and chemical characteristics of this biomass was first analyzed. To determine the productivity of syngas from this biomass, fluidized bed gasifier was used in this work. The effects of gasification process parameters (i.e., equivalence ratio and temperature) on product yield and producer gas compositions were examined. Besides, the effects of equivalence ratio towards higher heating value of syngas and carbon conversion efficiency were analyzed. Based on the ultimate analysis results, the molecular formula of Napier gas was CH1.56O0.81N0.0043. Meanwhile, the higher heating value of such biomass was determined as 16.73 MJ/kg, which was comparable to other biomasses. It is noted that in this work, the volatile matter was determined as 85.52% and this promoted gasification process remarkably. The dynamics of the reactions involved were observed as a significant variation in product yield and biogas components were recorded at varying equivalence ratio and gasifier operating temperature.

The present study aimed at the screening of parameters for electrocoagulation treatment of treated palm oil mill effluent using minimum-runs resolution IV design. The responses examined include: chemical oxygen demand removal (%), total suspended solids removal (%) and turbidity reduction (%), and the varied dependent factors comprise: electrical current density (mA/cm2), time (min), pH, electrolyte concentration (g/L), stirring speed (rpm), electrode spacing (mm) and electrode configuration (monopolar or dipolar). The statistical results revealed that the current density has a significant influence on the treatment performance at two-level interactions with pH, electrode spacing and electrode concentration and at three-level correlations with time and pH. Thus, the most important factors affecting the removal efficiency of the organic compounds were found to be pH, time, electrode spacing, electrolyte concentration and electrode configuration at a P value less than 0.05, respectively, in the descending order of significance. Therefore, the optimized electrocoagulation process could be reached with current density equal to 5 mA/cm2, electrolysis time of 5 min, electrode spacing of 5 mm and using monopolar electrode configuration. This combination provided the maximum ability of the process for chemical oxygen demand (68.84%), total suspended solids (93.27%) and turbidity reduction (92.88%) predictions, with the corresponding experimental values of 69.27, 97.59 and 96.91%, respectively.

The effects of a commercially produced Tannin-based coagulant and flocculant (Tanfloc) in a biofilm process pilot plant treating municipal wastewater were investigated. The investigated flow rates were 10, 14 and 18 L/min for the entire pilot plant, with two additional flows of 22 and 24 L/min were used for flocculation and sedimentation processes only. There was no clear deterioration in flocculation efficiency; even at 24 L/min, where the flocculation time was only 7.5 min. In terms of the clarification process, the enhancement was remarkably good; especially at high flows. Without Tanfloc, the removal efficiencies in the clarifier were less than 20%, 40%, 22% and 8% for turbidity, total suspended solids, biochemical oxygen demand and total phosphate, respectively. Meanwhile, when Tanfloc was used, they achieved 75%, 61%, 60% and 16% for the same respective pollutants. A significant rise in dissolved oxygen level in the aeration tank was observed when Tanfloc was applied (promising saving of energy during aeration). For instance, a dissolved oxygen level of 3 mg/L measured in experiments without Tanfloc, witnessed a climb to 6 mg/L when Tanfloc was used. In addition, volatile suspended solids concentration in the aeration tank decreased when Tanfloc was used (promising less production of sludge). Other measurements of total suspended solids (mg/L), chemical oxygen demand (mg/L) and biochemical oxygen demand (mg/L) in the experiments without Tanfloc were in the range (12–36), (60–104) and (24–50), respectively. Remarkably Tanfloc was able to reduce these measurements to low levels of (9–26), (28–68) and (7–24). In conclusion, the results suggest Tanfloc as promising agent to enhance the performance of clarification in a biological treatment unit. In light of this enhancement, Tanfloc could be used to upgrade existing treatment plants or design compact treatment units.

Highly sensitive and rapid method for the determination of prulifloxacin (PUFX) has been developed on the basis of ion association reaction of PUFX, Y(III) and eosin Y (EY). In pH 6.5 BR buffer medium, PUFX reacts with Y(III) to form a 2:1 cationic chelate which further reacts with EY to form 2:1 ion-association complex. As a result, not only the spectra of absorption are changed, but quenching of fluorescence and significant enhancement of resonance Rayleigh scattering (RRS) is observed. Furthermore, a new RRS spectrum would appear, and the maximum RRS wavelength was located at about 375 nm. The fluorescence quenching (FQ) and enhanced RRS intensity were directly proportional to the PUFX concentration in the ranges of 1.5 – 7.6 μg mL–1 and 0.004 – 3.0 μg mL–1 with detection limits 8.5 ng mL–1 and 1.1 ng mL–1, respectively. The optimum conditions of RRS method and the effects of coexisting substances on the reaction were investigated. In addition the composition of ion-association complexes, the reaction mechanism, the energy transfer between absorption, fluorescence and RRS and reasons for RRS enhancement were discussed. The methods were applied to the determination of PUFX in pharmaceutical samples with satisfactory results.

There is evidence that several systematic researches recognized the importance of using polymers in drugs manufacturing Natural polymers are usually biocompatible biodegradable and non expensive like chitosan Chitosan is one of the natural biodegradable groups of polymers that have been extensively used for microencapsulation of drugs like isoniazid propranolol and aspirin This natural polysaccharide has many pharmaceuticals applications such as oral and parenteral delivery of drugs It is important for a wide range of scientific and industrial processes to know the applications of chitosan microparticles loaded drugs in pharmaceuticals fields Recently this issue was the objective of many research papers in the literature Chitosan can also be combined with other polymer to encapsulate many drugs in order to achieve targets with performance delivery Recent advances in microencapsulation methods have facilitated investigation of chitosan usage to load drugs This review about the preparation of chitosan based micro and particles by many fabrications methods of pharmaceutical applications including coacervation drying techniques ionic cross linking ionotropic gelation and emulsion solvent diffusion method

Durian peel is among the renewable biomass wastes abundantly available in Malaysia. An implication of untreated biological materials for biosorption process was intensively reported, that prioritize our work towards sorbent modification. The biosorption potentials of hydrochloric acid (HCl) modified durian peels (HAMDP) for removal of Zn (II) from simulated wastewater was investigated. Characterization of HAMDP was performed by ATR-FTIR, SEM and BET. Spectroscopic studies showed the predominant contributors for Zn (II) biosorption on HAMDP is attributed to hydroxyl, carbonyl, carboxyl and amides groups. Batch adsorption studies revealed optimum conditions of pH 8, 0.5 g biosorbent dose, 4 h contact time and reaction temperature of 313 K. Non-linear isotherm models suggested applicability of Tempkin and Langmuir models at 313 K. The Langmuir maximum adsorption capacity was 36.73 mg/g. Kinetic studies revealed applicability of pseudo-second-order model. Webber-Morris model indicated possible role of diffusion of Zn (II) within the particles of HAMDP during the sorption process. Freundlich constant and activation energy values confirmed the physical nature of the process. Thermodynamic studies indicated that the process is exothermic and spontaneous. Regeneration studies depicted that HAMDP is economically viable. Conclusively, HCl served two significant purposes, namely; a good modification reagent and best eluent in Zn (II) recovery. Therefore, HAMDP is relatively effective, efficient, economical and most importantly “renewable and sustainable” biosorbent for Zn (II) removal from wastewater.

Most developing countries in the world face the common challenges of reducing air pollution and advancing the process of sustainable development, especially in China. Air pollution research is a complex system and one of the main methods is through numerical simulation. The air quality model is an important technical method, it allows researchers to better analyze air pollutants in different regions. In addition, the SCB is a high-humidity and foggy area, and the concentration of atmospheric pollutants is always high. However, research on this region, one of the four most polluted regions in China, is still lacking. Reviewing the application of air quality models in the SCB air pollution has not been reported thoroughly. To fill these gaps, this review provides a comprehensive narration about i) The status of air pollution in SCB; ii) The application of air quality models in SCB; iii) The problems and application prospects of air quality models in the research of air pollution. This paper may provide a theoretical reference for the prevention and control of air pollution in the SCB and other heavily polluted areas in China and give some1inspirations for air pollution forecast in other countries with complex terrain.

Since the industrialisation of Malaysia, the energy demand which mainly relied on fossil fuels has risen continuously. Therefore, all parties including the government, academic society and communities have explored alternative fuel resources to improve the reliability and security of energy supply to meet the future energy. In recent years, biomass has been identified as one of the most promising renewable energy resources compared to hydro, solar, wind, etc. It is projected that energy crops could potentially supply around 200-400 EJ/year in Malaysia at a competitive cost by 2050. Perennial grass is one type of energy crop that could address the above mentioned challenge. In this work, Napier grass (NG) is chosen as the subject due to its desirable characteristics (availability, high growth rates, carbon neutrality and high volatility). In order to investigate the feasibility of NG for heat and power application, the thermal decomposition characteristics, reactivity, and kinetic of NG needed were tested via thermogravimetric analysis (TGA) under inert (nitrogen) and air atmosphere conditions, respectively. The results indicated that NG biomass has great potential as sustainable energy fuel source for energy generation via gasification process.

Chemical composition and flocculation efficiency were investigated for a commercially produced tannin – based coagulant and flocculant (Tanfloc). The results of Fourier Transform Infrared Spectroscopy (FTIR) and Energy Dispersive Spectroscopy (EDX) confirmed what claimed about the chemical composition of Tanfloc. For moderate polluted municipal wastewater investigated in both jar test and pilot plant, Tanfloc showed high turbidity removal efficiency of approximately 90%, while removal efficiencies of BOD5 and COD were around 60%. According to floc size distribution, Tanfloc was able to show distinct performance compared to Polyaluminum chloride (PAC). While 90% of flocs produced by Tanfloc were smaller than 144 micron, they were smaller than 96 micron for PAC. Practically, zeta potential measurement showed the cationic nature of Tanfloc and suggested coincidence of charge neutralization and another flocculation mechanism (bridging or patch flocculation). Sludge Volumetric Index (SVI) measurements were in agreement with the numbers found in the literature, and they were less than 160 mL/g. Calcium cation as flocculation aid showed significant improvement of flocculation efficiency compared to other cations. Finally Tanfloc showed competing performance compared to PAC in terms of turbidity, BOD5 and COD removal, floc size and sludge characteristics.

Omega-3 poly unsaturated fatty acids (PUFA) particularly eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA), have many health benefits including reducing the risk of cancer and cardiovascular disease. Recently, the use of ionic liquids (ILs) in lipid extraction from microalgae provides the potential to overcome common drawbacks, offers several other benefits. To date, very limited researches are available to focus on extracting microalgae lipid and PUFA in particular by using ILs. The objective of current work is to screen the potential ILs that can be applied in EPA extraction. In this study, fast ILs screening was performed with the help of a conductor like screening model for real solvents (COSMO-RS) and the ILs with higher capacity values for use in extraction of EPA were compared. According to the results, the highest capacity for EPA extraction among 352 screened cation/anion combinations belongs to [TMAm][SO4]. It is expected to achieve a higher yield of EPA once applying this combination as the solvent in the process of extraction. ILs with small anions were observed to have higher capacities, as well possessing higher charge density compared to larger ones, and therefore, they are more preferable for extraction purposes. Moreover, shorter alkyl chain cations are preferred when using imidazolium-based IL, which agrees with experimental data.

Orotic acid (OA) nanoparticles were prepared using the freeze-drying method. The antihypertensive activity and antioxidant capacity of OA and orotic acid-loaded gum arabic nanoparticles (OAGANPs) were examined using the angiotensin-converting enzyme (ACE), 1,1-diphenyl-2-picrylhydrazyl (DPPH), nitric oxide (NO), and β-carotene assays, as well as the quantification of total phenolic content (TPC). The DPPH and NO scavenging activities of OAGANPs were significantly higher than those of the OA solution. The β-carotene bleaching assay of OAGANPs showed a dose-dependent trend, while 500 μg/ml was significantly more effective than the other concentrations, which exerted 63.4% of the antioxidant activity. The in vitro antihypertensive assay revealed that the OAGANPs exhibited the most potent ACE inhibition activity, when compared to the OA solution. Hence, results revealed the potential of preparing the OA as a nanoparticle formulation in enhancing the antioxidant and antihypertensive properties compared to the OA solution.

Vortex flow forms due to spiral motion of the air bubbles around water in the aeration tank. The formation of vortices would indicate the mixing pattern of water and air in the aeration tank. The mixing of two phases such as air-water or water-air flow systems in the aeration tank is important to increase oxygen transfer efficiency in aeration process. With different process parameters of the aeration tank such as the diameter of pore size of the membrane, diameter of diffuser and air mass flow rate are simulated using ANSYSTM CFD software. When the air mass flow rate increasing, the diameter of pore size decreasing, the air-water or vice versa are mixed homogenously and increases the oxygen transfer efficiency. The air-water mixing efficiency increases if the diameter of membrane pore size decreases at higher mass flow rate and the diameter of diffuser is in the practical range which is between 4 to 12. An improvement of vortices occurs in an aeration tank when higher strength of air velocity curl occurs.

Calculation work is carried out in the present project to study the effect of different parameters on hydrodynamics of gas-liquid flow by using CFD. The steady state and transient, three dimensional simulations are performed of the whole bubble column for various inlet gas and sparger designs. A standard k-ε is used to describe turbulence occurring in the continuous fluid. Results show he asymmetric recirculation stronger with an increase in the number of holes giving better mixing. The gas hold-up increased with superficial gas velocity but independent of the sparger design at high velocity. Comparison of simulation results with the previous experimental work data has provided a successful validation of the model.

Ionic liquids (ILs) have been recognized as superior solvent due to their exclusive properties, green and varied applications in chemical industries. ILs can be apply as solvent in extracting lipid from algal biomass. This study examined the application of microwave-assisted extraction (MAE) with ILs to extract total lipids from microalgae for biodiesel production. 1-ethyl-3-methyl imidazolium chloride ([EMIM]Cl) IL was utilized as the solvent and microwave irradiation applied for the pretreatment method. The experimental findings were compared with those from conventional method using Soxhlet extraction. For [EMIM]Cl plus microwave irradiation assisted extraction, it was reveald that the highest lipid yield was achieved 13.9% in the optimum condition at 3.3 w/v of solid loading, process duration of 5 min, temperature of 80 °C and microwave power of 800 W. Also, microwave irradiation with IL had improved the lipid extraction up to 3.1 times compared to the Soxhlet result. The findings from this study displays that the MAE with IL has the potential to be applied in extracting compounds from biomass.

The mass loss of three wood species in Malaysia, Shorea laevis, Koompassia malaccensis, and Shorea parvifolia were measured against time and temperature at three different heating rates (5, 10 and 20 °C/min) in nitrogen environment, through thermogravimetry analysis (TGA) technique. This measurement revealed that the decomposition of these wood generally occurred in three stages, the dehydration stage, the active stage, and; the passive stage. The maximum decomposition peak in derivative thermogravimetric (DTG) analysis curve shifted towards higher temperature range with the expedition in heating rate. The kinetic decomposition parameters of the timbers were determined by adopting thermal kinetic method of Coats and Redfern. Principally, the density and moisture content of timber does not influence the kinetic parameters studied in this work. Overall, the thermal decomposition in the second-stage (active stage) was dominated by the hemicellulose and cellulose while the decomposition of lignin was apparent in the third-stage (passive stage) of pyrolysis. The higher activation energy in the second-stage indicates that more cellulose is contained in the sample. The activation energy of lignin is observed to be much lesser compared to the activation energy of the hemicellulose and cellulose for two species tested except for the Shorea parvifolia.

Tanfloc, a natural tannin-based coagulant and flocculant, was used in this study as a pre-treatment agent for a biofilm unit that was used to treat municipal wastewater. The point of interest in this study was the effect of the extended use of Tanfloc (around 2 months) on the biofilm bacterial community. Two identical bench-scale aeration tanks were run in parallel, one of them treating settled wastewater, and the other pre-treated (flocculated/settled) wastewater using Tanfloc. The results showing the effect of Tanfloc was very apparent on the characteristics of the wastewater. At a hydraulic retention time of 4 h, the relatively short retention time was not enough to achieve any noticeable removal of ammonia without Tanfloc. In contrast, the 4 h retention time was sufficient to achieve around 70 % removal of ammonia when Tanfloc was used. This improvement in the nitrification process was attributed to the bacterial community of the biofilm as a consequence of Tanfloc use. A bacterial 16S rRNA analysis of the biofilm showed a significant increase in the percentage of ammonia-oxidizing bacteria (3.33 %) and nitrite-oxidizing bacteria (7.8 %) in the experiment using Tanfloc, compared to only 0.073 % and 0.19 % respectively, in the experiment without Tanfloc.

The most challenging issue faced by the petroleum industry in recent years was the water production during crude oil and gas extraction. This challenge has caused aggravated damages to treatment facilities by increasing the cost of production as water production increased over time. However, most of the water produced from oil and gas platforms is produced as water in oil emulsion. Treating emulsion has been experienced using techniques involve specific chemical methods. This study used the bottle test technique to investigate the performance of non-ionic demulsifiers, Propargyl Alcohol (PA) and Triethylene Glycol (TG), in breaking water in oil emulsion. Subsequently, a factorial design was applied for the characterisation of five variables, namely demulsifier dose, toluene concentration, pressure drop, temperature, and sitting time. Then, the significant factors were further analysed using Central Composite Design (CCD) based on the Response Surface Method (RSM). In particular, CCD was used to study the influence of demulsifier dose, toluene concentration, pressure drop, temperature, and sitting time on the response and to find the optimal condition to achieve maximum dehydration. Additionally, Analysis of Variance (ANOVA) was used to test the accuracy of the mathematical models established using CCD. The results show that demulsifier dose, temperature, and sitting time were the most significant parameters for breaking the emulsion, and that the optimal values for the input variables were successfully obtained using RSM.

The flow rate or fluid velocity measurement is important to maintain fluid flow quality performance in the systems. This study focuses on determination of volumetric flow rate measurement and to calibrate the conventional flowmeter using industrial radiotracer approach in quadrilateral gas-liquid bubble column reactor. In this work, two different radioisotopes which emit γ-ray have been chosen as radioactive tracer which is

Concentration of goat milk using cross-flow filtration unit with 10KDa molecular weight cut off (MCWO)-sized ultrafiltration membrane was examined under various operating conditions. The parameters to be optimized are trans-membrane pressure (TMP) and cross-flow velocity. Permeate flux is decreased with time due to fouling of the membrane. The localized membrane fouling may be reduced by increasing the feed flow rate and TMP to mitigate overall membrane fouling. By doing so, the transmission of lactose will also increase. The aim is to produce concentrated goat milk with minimal lactose content and thus high concentration of protein. Spray-drying method is used to convert the concentrated non-lactose milk obtained into milk powder. The milk powder then was characterized in terms of its surface particle, solubility, and nutritional content with the well-commercialized non-lactose milk. This project tackles understanding to minimize the deposition rates of particles on membrane by optimizing the involved parameters and be proved by comparing the yield obtained with well-commercialized non-lactose milk. Keywords:Goat’s milk, lactose intolerance, ultrafiltration, spray dry,membrane, concentration

Radioactive Particle Tracking (RPT) technique has emerged as a potential and versatile technique, both in terms of richness of information and applicability to a variety of multiphase flow systems. RPT is not an off-the-shelf technique and thus has to be developed by the intended user. This paper is intended to present a simple method and procedure for preparing suitable radioactive particles tracer (Au-198 and Sc-46) irradiated simultaneously with neutrons using TRIGA Mark II research reactor. These present work focuses on the performance evaluation of encapsulated gold and scandium particle to be used as single radioactive particle tracer using qualitative and quantitative neutron activation analysis (NAA) and X-ray micro computed tomography (micro-CT) scanner installed at Malaysian Nuclear Agency.