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Development of low-cost, sustainable and environmentally friendly biodiesel is a key focus in the energy industry worldwide. It is known that selecting suitable raw feedstock materials and optimising an efficient transesterification process are crucial in biodiesel production. Effective and realistic strategies are imperative in order to boost the quantity and quality of biodiesel production. In fact, scientists and researchers have put great effort to improve the market value of their biodiesel products. In recent years, the feasibilities of several raw materials as feedstocks to produce biodiesel have been assessed by researchers. These materials were reported able to produce biodiesel that met international standards, namely the American Society for Test and Materials D6751 and European Standard 14214. Although these biodiesel products have met the quality criteria, their fatty acid methyl ester (FAME) contents differ. This review focuses on optimum conditions (methanol/oil molar ratio, amount of catalyst, reaction temperature and reaction time) of transesterification process for biodiesel production from various feedstocks. The influence of these factors on FAME composition is also discussed. This review is beneficial to scientists working on biodiesel production particularly for the evolution of eco-friendly and low-cost biodiesel.

Biodiesel from insect larvae is an alternative to plant biodiesel, which have issues of using edible plants. On the contrary, insects can grow on waste. Although the conversion of larval lipids to biodiesel is known, characterisation of larval biodiesel is rarely reported. Here, black soldier fly larvae were cultivated for 20 days on kitchen waste. Larval lipids were extracted and converted to biodiesel by two-step transesterification. Analysis by optical polarisation microscopy from − 5 to + 15 °C showed tiny needle-like shaped crystals. Fourier transform infrared spectra of black soldier fly biodiesel revealed absorption bands at 1459 and 1435 cm−1 corresponding to methyl ester, the main functional group of biodiesel. Nuclear magnetic resonance (NMR) analysis confirmed the presence of methyl ester by showing peaks at 3.6 and 2.3 ppm by 1H NMR, and at 176 and 51.56 ppm by 13C NMR. Overall, our results confirm the successful conversion of black soldier fly larval lipid to biodiesel. This biodiesel met the American Society for Test and Materials D6751 and European Standard 14214.

Purpose: Actinic keratoses (AK) are precancerous lesions that can progress to squamous cell carcinoma. Photodynamic therapy (PDT) and topical 5-fluorouracil (5FU) are commonly used agents for AK. Empirical reports suggest that combining them can improve the therapeutic response. However, the optimal combined regimen was not clear in terms of proper sequence, timing, and mechanism. This clinical study explored mechanisms of action for neoadjuvantal 5FU and PDT for treatment of AK. Patients and Methods: A bilaterally controlled trial (17 patients) was performed. One side of the body (face, scalp, forearms) received 5FU pretreatment for 6 days, whereas the other side served as no-pretreatment control. Methylaminolevulinate cream was applied to both sides for 3 hours, and protoporphyrin IX (PpIX) levels were measured by noninvasive fluorimetry and skin biopsy. After red light illumination, lesion clearance was assessed at 3, 6, 9, and 12 months after PDT. Results: PpIX levels were increased 2- to 3-fold in 5FU-pretreated lesions versus controls. Altered expression of heme-synthetic enzymes (coproporphyrinogen oxidase and ferrochelatase) and induction of p53 were observed, probably accounting for increased PpIX and subsequent cancer cell death. Relative clearance rates after PDT with or without 5FU pretreatment were 75% versus 45% at 3 months, and 67% versus 39% at 6 months, respectively; these differences were statistically significant. Conclusions: Serial 5FU and PDT improve AK clearance by at least two mechanisms, enhanced photosensitizer accumulation and p53 induction. Because 5FU and PDT are FDA-approved modalities, the combined regimen can be readily employed in clinical practice to reduce AK burden and reduce SCC risk. Clin Cancer Res; 24(13); 3026–35. ©2018 AACR.

The objective of this study was to investigate the effect of crosslinking agents on the mechanical and thermal properties of protein-based bioplastic. In this work, Glutaraldehyde (GA) and Glyoxal (GLY) were used at different compositions at 2pph, 4pph, 6pph, and 8pph. GA and GLY were added during bioplastics production using two roll mill. Samples were hot-pressed into dumbbell-shaped for further characterization. Incorporation of crosslinking agents was observed using Fourier Transform Infrared Spectroscopy (FTIR) while thermal stability was determined using Thermogravimetric Analysis (TGA) and Differential Scanning Calorimetry (DSC). The FTIR result showed the presence of amide I at peak 1630 cm−1, indicating interactions between the crosslinking agent and polypeptide chains. The tensile properties were investigated by using Universal Testing Machine. It was found that GA has better crosslinking with a tensile strength at 0.2133 MPa compared to the GLY with the tensile strength at 0.1985 MPa at 8pph composition. The crosslinking between the crosslinking agent and protein-based bioplastic affected the thermal stability where GA showed higher thermal stability than GLY at 8pph composition.

In this study, a two-step transesterification process was applied to convert crude BSF larval oil into biodiesel. The effects of methanol:oil (molar ratio), catalyst amount (weight %), reaction time (minutes) and temperature (°C) on biodiesel production were investigated. Central Composite Design (CCD) of Response Surface Methodology (RSM) was used to optimise experimental data obtained from these four variables. The prediction of biodiesel yield was made by employing a quadratic model, whereby the R2 values were greater than 0.99. Based on optimisation studies, a combination of an application of petroleum ether and reaction time of 6 hours was the best to extract crude larval oil with 47% of lipid yield. Meanwhile, methanol:oil molar ratio of 12:1, catalyst (NaOH) concentration of 1.0 weight %, a reaction time of 32 minutes and temperature of 60°C were required to obtain biodiesel with 96% of production yield from BSF crude larval oil. Both BSF crude larval oil and biodiesel were characterised using several analytical instruments such as Fourier Transform Infrared (FTIR) spectrometer and Gas Chromatography – Flame Ionisation Detector (GC-FID). Overall, findings from this study highlight the potential to produce eco-friendly biodiesel from BSF larvae reared on soya residue.

The aim of this study is to determine sensitivity of new recipes polymer gel HEMATEG with varied x-ray exposure by using UV-visible spectrophotometer as an evaluation technique. The gels were irradiated by x-ray radiation and the polymerization of HEMATEG were followed. Polymerization was read based on absorption spectra in the range wavelength UV 300 nm to 700 nm. The dependency of polymerization with increasing of exposure dose was determined by changes in the band gap energy (Eg) and Urbach energy (∆E). In the UV-visible region,Egwith indirect transition of HEMATEG were decreased with increasing radiation dose while,∆Ewere increased with increasing radiation dose. This observation supported the increase of structured disorder of the polymer with increasing radiation dose. This study proved that HEMATEG had a high potential to be used as a 3-dimensional dosimeter in the diagnostic x-ray.

(Ethylene-propylene-diene monomer)/(recycled ethylene-propylene-diene monomer) (EPDM/r-EPDM) blends filled with constant mica loading were compounded at various blends ratios (i.e., 90/10, 80/20, 70/30, 60/40, and 50/50). Results indicated that scorch time decreased with increasing r-EPDM content, whereas curing time, minimum torque, and maximum torque show the opposite trend. The tensile strength, stress at 100% elongation, and elongation at break value increased with increasing r-EPDM loading in the blend systems and the optimum properties occurred at 70/30 EPDM/r-EPDM blends ratio. The thermal stability of EPDM/r-EPDM blends increased with increasing r-EPDM content in the blends but the swelling percentage showed the opposite trend with a greater addition of r-EPDM content in the blends. J. VINYL ADDIT. TECHNOL., 21:1–6, 2015. © 2014 Society of Plastics Engineers

The influence of silane (bis[3-triethoxysilylpropyl] tetrasulfide) coupling agent on the properties of ethylene-propylene-diene monomer rubber (EPDM)/mica composites was studied. Both EPDM/mica composites with silane and those without silane were compounded by using a two-roll mill at various filler loadings (i.e., 100/0, 100/10, 100/30, 100/50, 100/70). The tensile and thermal properties as well as the fracture surfaces of the composites were investigated by using an Instron Universal Testing Machine, a thermal gravimetric analyzer, and a field emission scanning electron microscope. The results indicated that the optimum cure time (t90) and scorch time (ts2) values were shorter, whereas the maximum torque (MH) value was slightly higher, for EPDM/mica composites with silane compared to those without silane. The tensile properties, modulus at 100% elongation, and modulus at 300% elongation increased for the composites made with silane, and the optimum filler loading for those properties was 50 parts by weight per hundred parts of rubber. In addition, thermal stability and swelling ratio for both composites improved with increased filler loading. However, the composites with silane showed better thermal stability and swelling ratio because of stronger linkage at the rubber-filler boundary, which promoted filler dispersion. J. VINYL ADDIT. TECHNOL., 20:116–121, 2014. © 2014 Society of Plastics Engineers

Thymol is a hydrophobic active ingredient and widely used as an alternative pesticide for pest control. However, due its low solubility in water, a water-soluble carrier is required in its formulation. Therefore in this study, the potential of an amphiphilic chitosan, namely lauryl glycol chitosan (LGC) as a carrier to encapsulate and release thymol was evaluated. The physical and chemical properties of LGC were characterized using Fourier Transform Infrared (FTIR) Spectrometer, Proton Nuclear Magnetic Resonance (1H NMR) Spectrometer, UV-Visible Spectrophotometer, Thermogravimetric Analyser (TGA) and Transmission Electron Microscope (TEM). A Fluorescence Spectrometer was used to determine the critical micelle concentration (CMC) value of LGC in aqueous solution. The encapsulation efficiency of LGC for thymol was determined by using a High Performance Liquid Chromatography (HPLC). The FTIR and 1H NMR analyses confirmed the structure of the synthesized LGC. It was noted that the addition of lauryl and glycol groups to the chitosan backbone has enhanced the solubility properties of chitosan in neutral and basic media. TEM observation confirmed that LGC could form self-aggregates in the solution with a spherical shape. The CMC value determined for LGC was 0.008 mg/mL. LGC exhibited good affinity towards thymol with an encapsulation efficiency of 58%. The findings from in vitro release study showed that the LGC could prolong the release of thymol from its micelles. Results from this study highlight that LGC possesses great characteristics to be further developed as a promising carrier in the pesticide formulation.

Dyes are stable organic pollutants that have been used in many industries and become one of the toxic contaminants for the environment. This research aimed at preparing a magnetic chitosan nanocomposite (MCN) as an effective adsorbent for cationic and anionic dye removal from aqueous solution. The MCN was synthesized using a coprecipitation method. The physical properties of MCN were characterized using elemental analysis (CHNO), vibrating sample magnetometry (VSM), scanning electron microscopy (SEM), thermogravimetric analysis (TGA) and X-ray diffractometry (XRD). The results confirm that chitosan has been embedded on the surface of magnetic material and shows superparamagnetic properties behavior. A series of adsorption were conducted to investigate dosage of adsorbent, contact time and initial dye concentration to obtain the optimum condition of adsorption for both methylene blue (MB) and congo red (CR) dyes. The experimental equilibrium adsorption were then analyzed by the Langmuir and Freundlich isotherm models. Based on the correlation coefficient (R 2) values, the equilibrium adsorption data were fitted to the Langmuir isotherm model. The maximum adsorption capacity (q m) obtained from the Langmuir isotherm model for MB and CR onto MCN was 0.1308 and 1.8257 mg/g, respectively. Results highlight the potential of MCN application as an adsorbent for water contaminated by dyes.

The overall objective of present work was to prepare and use chitosan-titanium dioxide (CS-TiO2) nanocomposite as an adsorbent to remove two toxic dyes, namely Methyl Orange (MO) and Rhodamine B (RhB) from the aqueous solution. This work consists of two main parts, namely adsorption and characterization studies. For adsorption studies, several experimental parameters were studied such as the effect of initial concentration, solution pH and adsorbent dosage. Meanwile, Scanning Electron Microscope (SEM), Thermogravimetric Analyser (TGA), and X-ray Diffractometer (XRD) were used for characterization studies. The outcomes have shown that the equilibrium data correlated well to Freundlich isotherm model with adsorption capacity at equilibrium (K F) was determined as 1.608 mg/g for MO and 7.646 mg/g for RhB, respectively. Based on SEM analysis, the rod- and needle-like deposits on the surface of CS-TiO2 nanocomposite were disappeared following interaction with MO and RhB. There were cube-like deposits observed on the surface of CS-TiO2 nanocomposite after adsorption of MO, while a dense and uneven surface texture were observed after adsorption of RhB. From TGA analysis, CS had two degradation stages, while CS-TiO2 nanocomposite had three steps of decomposition. Furthermore, XRD results observed diffraction peaks for CSTiO2 at 2θ = 34.075°, 29.235°, 25.47° and 20.26°.

In this work, the influence of silane (bis (3-triethoxysilylpropyl) tetrasulfide) or Si69 coupling agent on properties of EPDM/mica composites was studied. Both EPDM/mica composites with silane and without silane were compounded using two roll mill at various filler loading (i.e., 100/0, 100/10, 100/30, 100/50, 100/70). The tensile and thermal properties as well as fracture surfaces of composites were tested using Instron Universal Testing Machine, Thermal Gravimetric Analysis (TGA) and Emission Scanning Electron Microscope (SEM). The results indicated that the optimum cure (t90), scorch time (ts2) value was lower, while maximum torque (MH) value slightly higher for EPDM/mica composites with silane compared to EPDM/mica composites without silane. The tensile properties, M100 and M300 value increased for EPDM/mica composites in the presence of silane and the optimum filler loading for those properties occurred at 50 phr. In addition, thermal stability and swelling ratio for both composites improved with increasing filler loading. However, EPDM/mica composites with silane show better thermal stability and swelling ratio due to stronger linkage taking place at the rubberfiller boundary and it promotes filler dis-agglomeration.

The objective of this study was to assess the potential of an amphiphilic chitosan derivative, namely N-hexanoyl-O-glycol chitosan (HGC) as a carrier agent for herbicide atrazine. The physicochemical properties of HGC were characterised using several analytical instruments. The critical micelle concentration (CMC) of HGC was determined using a Fluorescence Spectrometer. A High Performance Liquid Chromatography (HPLC) was used to determine encapsulation efficiency and loading capacity of atrazine in the amphiphilic chitosan derivative. Research findings found that the addition of hexanoyl and glycol groups to the chitosan backbone has improved the thermal stability of chitosan. TEM observation confirmed that HGC can form self-aggregation in the solution with spherical shape. The CMC values determined for HGC was 0.008 mg/mL. HGC also exhibited excellent encapsulation efficiency and loading capacity. The release profiles of atrazine loaded in HGC showed that it has different release behaviour than the pure herbicide in solution. In conclusion, the results from the study suggest that the amphiphilic chitosan derivative is applicable to be utilised as carrier agent for herbicide atrazine in pesticide formulation.

Department of Dermatology, University of California, Irvine, California 92612Background and Objectives: Optical clearing is amethod that temporarily reduces the optical scattering ofbiological tissues.Study Design/Materials and Methods: To determinethe optical clearing potential (OCP) of various chemicalagents, we examined the change in reduced scatteringcoefficientsofinvitrohumanskinafterapplicationdirectlyto the dermal side.Results/Conclusions: We found that the mean agentOCP did not correlate with refractive index or osmolality.Lipophilic hyperosmotic agents had a mean OCP less thanunity,indicating increasedoptical scattering. LasersSurg.Med. 36:72–75, 2005. 2005 Wiley-Liss, Inc.Key words: hyperosmotic agents; glycerol; scattering;dermatology; port wine stainsINTRODUCTIONIn biomedical applications, light is used for diagnosticimaging and therapeutics. The penetration depth of light inbiological tissue is restricted by absorption and scatteringevents. At visible and near infrared wavelengths, opticalscatteringdominatesoverabsorptionandismuchmoresigni-ficant in reducing light penetration into biological tissues.Optical clearing is a method for inducing a transient re-duction in optical scattering [1]. Studies have demonstratedtheincreasedpenetrationdepth andcontrastinopticalimag-ing [1–8]. Using a novel chemical agent (CA), Khan et al. [9]havedemonstratedforthefirsttimeinvivoopticalclearingofhuman skin. Various mechanisms for optical clearing havebeen proposed, including refractive index matching [1,5],dehydration [5,10,11], and collagen dissociation [12].Hyperosmotic CAs with refractive indices similar to thatof collagen have been shown to increase tissue transpar-ency. From results obtained with three CAs, Vargas et al.[13] suggested that increased light transmittance is pro-portionaltoCAosmolality.Inthisstudy,wequantitativelycharacterized a select group of hyperosmotic CAs. By mea-suring the optical clearing potential (OCP, defined below),we set out to determine whether there is a correlationbetween changes in optical scattering and osmolality andrefractive index.MATERIALS AND METHODSChemical AgentsWe studied three different groups of CAs: hydroxy-terminated, organic solvents, and organic acids as sum-marized in Table 1. Refractive index was measured with arefractometer (Cole-Parmer, Vernon Hills, IL). Osmolalitywas measured with a freezing point osmometer (AdvancedInstruments, Norwood, MA). Isotonic saline was used as anegative control (i.e.,no optical clearing expected).Glycerol(13 M)was used as a positive control (i.e., optical clearingexpected).Skin SamplesCryopreserved, dermatomed human skin (CommunityTissueServices,Dayton,OH)wasthawedtoroomtempera-ture( 258C).Asingleedgedrazorbladewasusedtocuttheskin into 2.5 cm 2.5 cm samples. Sample thicknessvariedbetween0.4and1mm,asdeterminedbyplacingthesample between two glass slides of known thickness andmeasuring the thickness of the sample/glass combinationwith a micrometer (Mitutoyo, City of Industry, CA). Tominimizeerrorduetosamplecompression,werecordedthesample thickness once the fine adjustment screw on themicrometer clicked once. Measurements on each samplewere initiated within 2 hours after thawing.Franz Diffusion ChamberAfter removal from between the glass slides, each skinsample was mounted in a Franz diffusion cell [14]. Thelowerreservoirwasfilledwithisotonicsaline.Eachsample

The aim of this study is to determine the sensitivity of HEMA-polymer gel mixture consist of monomer 2-hydroxyethyl methacrylate (HEMA) with different types of composition. Several composition of HEMA-polymer gel were fabricated and the gels were irradiated with radiation dose between 10 cGy to 100cGy by using x-ray machine and 100 cGy to 1400 cGy by using 6 MV photon beam energy of linear accelerator. The degree of polymerization was evaluated by using magnetic resonance imaging (MRI) with dependence of R2-dose response. Polymer gel consists of cross-linker, anti-oxidant Tetrakis(Hydroxymethyl)phosphonium chloride solution (THPC) and oxygen scavenger hydroquinone shows a stable sensitivity with highest dose dependency. Besides, the results shows the stage polymerization consist of induction, propagation, termination, and chain transfer were dependence with type of chemical mixture and radiation dose. Thus, normoxic HEMA-polymer gel with the different gel formulations can have a better dose resolution and an appropriate recipe must be selected to increase of the sensitivity required and the stability of the dosimeter.

Great interests in metallic oxides have emerged because of the promising properties of these materials for various applications such as solar cells and sensors. ZnO nanostructures with different morphologies were successfully synthesized from Zn(CH3COO)2•2H2O, NaOH and room temperature ionic liquid (RTIL) 1-decyl-3-methylimidazolium tetrafluoroborate, [DMIm][BF4] with ultrasound irradiation. Parameters such as the effect of sonication time (30, 60 and 90 minutes) and Zn(Ac)2 precursor to [DMIm][BF4] ratios of 3:5, 5:5 and 5:3 were investigated. X-ray diffraction patterns revealed that the ZnO nanocrystals were hexagonal zincite crystalline in structure. The band gap energies (Eg) were estimated to be 3.35-3.55 eV from the UV-Visible spectrum. The solution with the highest ratio of Zn was analysed with photoluminescence spectroscopy, which exhibited peaks at 362, 403, 468 and 539 nm, at room temperature. The micrographs of field emission scanning electron microscopy and transmission electron microscopy sho...

Two new compounds, 2,6-bis-O-digalloyl-3-O-galloylglucose and 2-O-trigalloyl-1,3,4,6-tetrakis-O-galloylglucose, along with four known gallotannins, were isolated and identified from the leaves of Haematoxylon campechianum. In addition, four known flavonoid and three simple phenolic compounds were also detected.

Investigation of the aerial parts of Parkinsonia aculeata collected from Egypt, afforded in addition to several known compounds, a new flavone C -glycoside. The structures were elucidated by spectroscopy of the permethylated derivatives.

Magnetostatic surface wave (MSSW) devices made with pure and gallium-substituted yttrium-iron garnet (Ga:La-YIG) films are described. These devices include nondispersive and dispersive delay lines, band-pass filters, oscillators, and resonators. By controlling the magnitude of the bias magnetic field and the temperature of operation, it is possible to tune these devices over a wide frequency range extending from 0.3 to 4 GHz and from 3 to 18 GHz using Ga:La-YIG and pure YIG films, respectively.

The status of magnetostatic wave (MSW) straight-edge resonators (SERs) and their applications in tunable oscillator circuits are reviewed. The resonators are based on magnetostatic waves propagating in high-Q cavities fabricated in thin ferrimagnetic yttrium iron garnet (YIG) films. The resonance frequency of these resonators can be tuned using a bias magnetic field. The theory of operation and design criteria for the straight-edge resonators are described with emphasis on the effect of the resonator parameters on the tuning range, power handling, and phase noise performance. The use of the SER as the frequency-selective element in oscillator circuits is reported. Examples of tunable oscillators are included. >

The performance of the magnetostatic surface wave straight-edge resonator (MSSW-SER) is presented. The resonator uses a rectangular YIG film to propagate MSSWs where the straight edge serves as a reflector. Problems arising from coupling to width mode resonances and their effect on the main resonance are investigated. Through a careful choice of YIG and transducer parameters, the interference effects of the width mode resonances with the main resonance are minimized. As a result, highQ tunable microwave resonators with a tuning range from 2–20 GHz, insertion loss less than 10 dB, and spurious rejection better than 10 dB could be designed and fabricated. This MSSW resonator could be used to construct a tunable low-phase-noise feedback oscillator. However, the tuning range of this MSW feedback oscillator is limited by the phase change of the external amplifier circuit.

The performance of magnetostatic surface wave delay line oscillators (MSWDLO) is presented. The oscillator consisted of a narrow band MSSW delay line in a feedback loop around a solid state amplifier. Power is coupled out by a directional coupler. A frequency range of 0.5-24 GHz was covered using highly doped, lightly doped and pure YIG films epitaxially grown on GGG substrates. The MSWDLO exhibited essentially linear tuning characteristics with output power greater than +5 dBm. Temperature cycling tests showed about 3 MHz/ °C variation in oscilation frequency over the 25-105 °C range. Phase noise measurements at different frequencies showed the single side band phase noise was typically less than -100 dBc at 10 kHz offset.

The flavonol glycosides of Carya pecan and Casuarina equisetifolia were isolated and identified. The branches of C. pecan were found to contain azaleatin-3-arabinoside, azaleatin- 3-rutinoside, quercetin-3-glucoside and caryatin-3′- or -4′-glucoside. From the leaves of C. equisetifolia eleven glycosides of kaempferol and quercetin were identified.