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Pd-based catalysts consisting of Pd nanoparticles on nitrogen-doped carbon quantum dots (N-CQDs) modified silica (SiO

CeVO4 as black-light-driven photocatalysts were successfully synthesized by a sol-gel method using citric acid as a complexing agent with subsequent 450–600°C calcination for 2 h. The as-synthesized products were characterized by thermogravimetric analysis (TGA), X-ray diffraction, Raman spectroscopy, Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM). The TGA analysis shows three-step weight losses caused by evaporation and decomposition of adsorbed water, organic compound, citric complex and phase transformation. X-ray diffraction and SEM results show that the samples were specified as tetragonal CeVO4 structure with particle sizes of 50–60 nm, 100–200 nm, 600–1000 nm and 800–1500 nm for 450, 500, 550, and 600°C calcination, respectively. In this research, CeVO4 nanoparticles with 450°C calcination showed the highest photocatalytic activity with •OH radical as the main active species involved in photodegradation of MB under black light irradiation.

0–4 wt% (0–4.11 mol%) Ce-doped MoO3 nanobelts were successfully synthesized by hydrothermal method at 180 °C for 20 h. X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) show orthorhombic MoO3 and Ce-doped MoO3 nanobelts with >10 μm long, 200–250 nm wide and their growth along the [010] direction. The photocatalytic performance of pure MoO3 and Ce-doped MoO3 nanobelts was investigated through photodegradation of methylene blue (MB) under visible radiation. In this research, 3 wt% (3.08 mol%) Ce-doped MoO3 nanobelts show the highest photocatalytic performance of 94.84% for degradation of MB induced by xenon visible radiation within 50 min.

Heterostructure Ag3PO4/Bi2WO6 nanocomposites were synthesized by precipitation-deposition method. X-ray diffraction (XRD), transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), photoluminescence (PL) spectroscopy and UV-visible spectrophotometry revealed that cubic Ag3PO4 nanospheres with

Cl-doped Bi 2 MoO 6 as visible light driven photocatalyst was synthesized by a hydrothermal method. The products were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). In this research, the Cl-doped Bi 2 MoO 6 samples have high crystalline orthorhombic Bi 2 MoO 6 phase. The 3 wt% Cl-doped Bi 2 MoO 6 showed excellent photocatalytic degradation of rhodamine B and followed the first order kinetics model under visible light irradiation.

A simple microwave method has been successfully developed to effectively produce Ag3PO4/Bi2MoO6 nanocomposites. X-ray powder diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) have been employed to determine the phase and morphology of the as-produced products. The photocatalytic activities were tested through the rhodamine B (RhB) degradation under visiblelight radiation. The interaction between cubic Ag3PO4 nanoparticles and orthorhombic Bi2MoO6 nanoplates has been characterized by XRD and TEM. In this research, the as-produced heterostructure Ag3PO4/Bi2MoO6 nanocomposites display effective photogenerated charge transfer between Ag3PO4 and Bi2MoO6 which can improve charge separation. The 10.0 wt % Ag3PO4/Bi2MoO6 nanocomposites showed the highest photocatalytic performance as high as 4.36 times of the pure Bi2MoO6 sample.

In this study, various sizes and chemical compositions of Au/Pd nanoparticles with core/shell structure were successfully prepared by employing a simple successive reduction method without addition of any stabilizer. The optical properties, morphologies, chemical compositions and crystal structures of the synthesized particles were fully characterized by using a combination of UV–vis spectroscopy, transmission electron microscopy, energy-dispersive X-ray spectroscopy, wavelength-dispersive X-ray spectroscopy, selected area electron diffraction and X-ray diffraction techniques. The catalytic activities of the synthesized Au/Pd nanoparticles for 4-nitrophenol reduction were also investigated and compared with monoatomic Au and Pd nanoparticles. The highest catalytic activity of bimetallic was obtained from AuPd 4 nanoparticles. With comparable size, Au/Pd nanoparticles provide better catalytic activity than those of monometallic Au and Pd. However, lower catalytic activities of Au/Pd nanoparticles are shown compared with that of smaller-size Au nanoparticles. This study also reveals that the size effect of catalysts plays important role on catalytic activity more than only changing their chemical constituents.

ZnO nanoplates were successfully synthesized by hydrothermal method in the solutions containing CTAB. The as-prepared samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Raman spectroscopy and Fourier transform infrared spectroscopy (FTIR). In this research, the as-synthesized samples were hexagonal wurtzite ZnO structure without any impurities and were composed of hexagonal ZnO nanoplates with the vibration mode of Zn–O bonds. The photocatalytic activity of hexagonal ZnO nanoplates showed superior photodegradation of methylene blue (MB) of 94.15 % under UV light irradiation within 80 min. The degradation efficiency of reused hexagonal ZnO nanoplates as photocatalyst indicated that ZnO nanoplates are very stable and reusable under UV light illumination.

PbMoO4 and PbWO4 were successfully synthesized by microwave radiation using different lead salts (acetate, chloride, nitrate and sulfate) and Na2MO4 (M = Mo, W) in propylene glycol. The products were characterized by X-ray diffraction (XRD), scanning and transmission electron microscopy (SEM, TEM), Fourier transform infrared (FT-IR), Raman spectroscopy and photoluminescence (PL) spectroscopy. In this research, morphologies, crystallization and photoluminescence of the products were influenced by the kinetics of anions, including the detection of M–O (M = Mo, W) stretching modes in the (MO4)2− tetrahedrons. Photoluminescence of PbMoO4 synthesized from Pb(NO3)2 and of PbWO4 synthesized from PbCl2 showed the strongest blue emission due to the electronic diffusion in tetrahedrons at room temperature.

CeVO4 nanostructures were successfully synthesized by polyethylene glycol-assisted hydrothermal process. The products synthesized in the solutions containing 0.000–0.020 g polyethylene glycol (PEG) were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). For the use of 0.015 and 0.020 g PEG, the products were uniform and pure tetragonal CeVO4 nanorods growing along the [001] direction. The stretching and bending modes of VO 4 3 - tetrahedrons were detected by Fourier transform infrared (FTIR) and Raman spectroscopy. Methylene blue was used as a representative dye pollutant for evaluating photocatalytic activity under UV radiation. In this research, CeVO4 nanorods synthesized in the solution containing 0.015 g PEG showed the highest photodegradation of 98.03% and the highest apparent rate constant of 0.0128 min−1 within 300 min.

Highly efficient visible-light-driven Ag3PO4/Bi2MoO6 hybrid photocatalysts with different mole ratios of Ag3PO4 were prepared via sonochemical method and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The results show that product are cubic Ag3PO4 nanoparticles supported on orthorhombic Bi2MoO6 nanoplates. Under visible light irradiation (>420 nm), the Ag3PO4/Bi2MoO6 photocatalysts displayed the higher photocatalytic activity than pure Bi2MoO6 for the decolorization of rhodamine B (RhB). Among the hybrid photocatalysts, 10% Ag3PO4/Bi2MoO6 exhibited the highest photocatalytic activity for the decolorization of RhB due to the efficient separation of electron–hole pairs.

Copper ferrite (CuFe2O4) nanoparticles were prepared in alkaline solutions containing Cu(NO3)2·6H2O and Fe(NO3)3·9H2O with the pH of 6–12 by microwave-hydrothermal method. The as-prepared products characterized by XRD were specified as cubic CuFe2O4 phase. Average sizes of the CuFe2O4 nanoparticles calculated by Scherrer formula are in the same range as those obtained by TEM analysis. FTIR shows main transmittance band at 585 cm−1, corresponding to stretching mode of tetrahedral complexes. Saturation magnetization, remanence and coercivity were increased with increasing in the particle-size and crystalline degree of the nanoparticles.

Shuttle-like BaMoO4 microstructure has been successfully synthesized from Ba(N03)2·4H20 and Na2MoO4·2H2O as starting materials in ethylene glycol solvent containing 20 mL 5 M NaOH by microwave radiation at 180 W for 30 min. The as- synthesized BaMoO4 product was characterized by X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, Raman spectrophotometry, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and photolumines­cence (PL) spectroscopy. XRD patterns revealed that the products was tetragonal BaMoO4 phase. SEM and TEM characteriza­tion showed that the product had a shuttle-like BaMoO4 microstructure. PL of the shuttle-like BaMoO4 microstructure showed a maximum emission at 466 nm excited by 280 nm wavelength.

Alumina-titanium carbide composite (Al2O3-TiC) is one of advance ceramic matrix composites (CMC) that have been used in machining tool and tribology application because of its excellent mechanical properties. Powder processing is often a chosen method to produce this family of material, i.e. hot pressed (HP), hot iso-static pressed (HIP), and pressure-less sintering (PS). These manufacturing techniques convert sub-micron powder into dense bulk component. Al2O3-TiC composite has been prepared by HIP process, containing 65%vol Al2O3and 35%vol TiC. The powders were pressured and sintered at temperature between 1250˚C - 1650˚C. Thermal residual stress from Al2O3-TiC manufacturing process is conventionally unavoidable. The aim of this study is to investigate the microstructure of HIPped Al2O3-TiC composite and its residual micro-strain using transmission electron microscopy (TEM) with selected area electron diffraction pattern (SADP) analysis. The Al2O3-TiC composite was prepared by high-precision machining/grinding processes then focus ion beam milling process was used to section the TEM lamella. Microstructures, grain size and phases were determined by TEM and X-ray diffractometry (XRD). Micro-strains of {200}TiC, {111}TiC , {220}TiC and {012}Al2O3were investigated by SADP (Selected Area Diffraction Pattern). Our result revealed there is approximately 0.01 compressive strains distributed in Al2O3-TiC composite.

0–3 % Ho doped Bi2MoO6 samples were synthesized by hydrothermal reaction at 180 °C for 20 h. Their phase, morphologies, atomic vibration and optical properties were characterized by X-ray powder diffraction (XRD), Raman spectrophotometry, Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), selected area electron diffraction (SAED) and UV-visible spectroscopy. In this research, the products were orthorhombic Bi2MoO6 nanoplates with asymmetric and symmetric stretching and bending modes of MoO6 octahedrons, and their strong absorption in the UV visible region.

Cubic and star-shaped dendritic PbS structures were successfully synthesized by the 120 °C and 10 h solvothermal reactions of lead nitrate and sulfur sources (thiourea and thiosemicarbazide). XRD, SEM and TEM analyses revealed the presence of pure cubic PbS phase with different morphologies, controlled by the sulfur sources. Cubic and star-shaped dendritic PbS crystals were respectively synthesized in the solutions containing thiourea and thiosemicarbazide as sulfur sources. Possible formation mechanisms of cubic and star-shaped dendritic PbS structures were also proposed.

Chrysomya megacephala (F.) (Diptera: Calliphoridae) is a medically important blow fly species in many parts of the world. In this study, we examined the ovary of C. megacephala at the ultrastructural level using light microscopy (LM), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Dissection of the ovaries revealed eight stages of ovarian development, thus providing a means of estimation of the age of females based on this organ. In the initial stage I (day 0-2), freshly-emerged flies up to three days old each display piriform germaria while the follicles are not yet well differentiated. In stage II (day 3), each follicle is nearly spherical and sepa- rating from the germarium. During stage III (day 4), each follicle is now easily distinguished from the germarium and is only connected by a thin interfollicular stalk. The nurse cells are completely surrounded by the cuboidal epithelial follicular cells. In stage IV (day 5-6), each folli- cle is spherical and considerably enlarged; whereas, the nurse cells within are more differentiated into individual round inclusions and grouped in the follicle chamber. Stage V (day 7) marks appearance of the visible oocyte at the posterior pole of the follicle. During stage VI (day 8), each follicle displays oocyte expansion anteriorly to occupyfrom one-third to one-half of the total length. In stage VII (day 9) the oo- cyte characteristically fills the posterior two-thirds of the total length of the follicle and in the final stage VIII (day 10), each follicle is com- pletely filled by an oocyte and nurse cells have disappeared. The micropyle and narrow, elongate median area are clearly seen in this final stage. SEM images reveal that the ovary is covered by an ovarian envelope, which is tough and thickened in 3-day-old adult ovarioles; whereas, it becomes thin and fragile in 9-day-old adult ovarioles. TEM analysis of ovarioles of 3-day-old adult flies shows that cuboidal follic- ular cells containing large nuclei with visible fibrils of muscle simply encircle the large compartments of nurse cells; whereas, ovarioles of 7- day-old adult flies displayed a more completely developed enclosure for the developing oocyte. This was observed by the presence of the outermost follicular cell layer with underlying eggshell, vitelline envelope, trabecular layer, and layer of granular material that surrounded the innermost oocyte.

Highly crystalline CaMoO 4 , SrMoO 4 , CaWO 4 and SrWO 4 nanoparticles were successfully synthesized by the co-precipitation of mixtures of Ca(NO 3 ) 2 4H 2 O or Sr(NO 3 ) 2 , and Na 2 MoO 4 2H 2 O or Na 2 WO 4 2H 2 O dissolved in ethylene glycol at room temperature (30 °C). Phases, morphologies, atomic vibrations and optical properties were analyzed by X-ray diffraction, transmission electron microscopy, Fourier transform infrared and Raman spectrophotometry, and ultraviolet–visible and photoluminescent spectroscopy. All products were proved to be MXO 4 (M = Ca and Sr, and X = Mo and W) with body-centered tetragonal scheelite structures, having round nanoparticles with the average sizes of 12.06 ± 1.65, 16.40 ± 2.44, 15.49 ± 2.19, and 15.40 ± 2.30 nm for CaMoO 4 , SrMoO 4 , CaWO 4 and SrWO 4 , respectively. Their ν 1 (A g ), ν 3 (B g ), ν 3 (E g ), ν 4 (B g ), ν 2 (A g ) and ν f.r. (A g ) vibration modes were also detected – being shifted to lower wavenumbers from MMoO 4 to MWO 4 , due to the change of efficient atomic mass of the oscillating ions between X 6+ and O 2− in the [XO 4 ] 2− complexes. Band gaps of CaMoO 4 , SrMoO 4 , CaWO 4 and SrWO 4 were determined to be 5.07, 3.72, 5.40, and 4.47 eV, respectively. Photoluminescent (PL) emissions were at 414, 413, 418, and 414 nm for CaMoO 4 , SrMoO 4 , CaWO 4 and SrWO 4 , respectively.

In Thailand, the hairy maggots of the blow flies, Chrysomya rufifacies (Macquart) and Chrysomya villeneuvi Patton, are of forensic importance. Both flies are closely related species, not only in the morphological appearance of their larvae and puparia, but also on the aggressive feeding habit of the former. In our continuing studies of forensically important flies, identification of immature ones needs particular attention. In this study, we reported the morphological comparison between the puparia of these two blow fly species using scanning electron microscopy (SEM). Observation revealed that the cuticular sculpture of tubercles along the dorsal and lateral segments had markedly different features: with C. rufifacies having many sharp spines assembling only at the tip, while of C. villeneuvi bore stout spines throughout the tubercle. A larger number of globules at the bubble membrane on the dorsolateral border of the fifth segment was found in C. villeneuvi (average 225) than in C. rufifacies (average 35), and more papillae was observed on the anterior spiracle in C. villeneuvi (13-15) than in C. rufifacies (9-12). However, the morphology of distinct net-like patches of the integument and structure of the posterior spiracle of both species were almost identical. Morphological comparison in this study permitted identification of the puparia of both fly species, particularly in areas where they co-exist.

The ultrastructure of adhesive device or the pulvilli, pad-like structure between the tarsal claws of the legs, is presented in the blowfly (Calliphoridae), housefly and relatives (Muscidae), and flesh fly (Sarcophagidae) through scanning electron microscopy. The blowfly species were Chrysomya chani, Chrysomya nigripes, Chrysomya pinguis, and Chrysomya villeneuvi; while those of the housefly and relatives were Musca domestica and Hydrotaea chalcogaster, respectively. Fresh fly species included Boettcherisca peregrina and Liosarcophaga dux. Numerous tenent setae were observed on the ventral side of the pulvilli. Two features of the tip of the tenent setae were found as a spatula-like (in C. chani, C. pinguis, C. nigripes, M. domestica, H. chalcogaster, B. peregrina, and L. dux) and spoon-like tip (in C. villeneuvi). Transmission electron microscopy of the tenent setae in M. domestica revealed the electron-lucent centrally located, suggesting an adhesive substance. These results provided anatomical information that allow us to not only understand the successful attachment of flies to smooth surfaces but also clarify their role as a mechanical carrier of microorganisms.

Examination of the puparia of the housefly, Musca domestica L. and blowfly Chrysomya megacephala (F.), through scanning electron microscopy (SEM), revealed many differences in the profile of their morphology. Special attention was focused on puparial characteristics used to differentiate between the two fly species studied, and between other forensically important flies. Results of this study indicate that the housefly puparia are almost evenly rounded at both ends and the anterior spiracle bears six papillae. A pair of pupal respiratory horns is found laterally before the posterior boundary of the first abdominal segment, bearing numerous papillae that have a longitudinal opening along the oval convex base. The peritreme of each posterior spiracle forms a crude forward or reverse D-shape, encircling three sinuous slits. The blowfly pupariums anterior spiracle contains 8-12 papillae. The pupal respiratory horns protrude slightly and in some specimens a group of approximately 38 globules on the bubble-like membrane may be observed. Each of the posterior spiracles is more or less an oval- shaped peritreme, encircling three straight spiracular slits. The anatomical features presented herein allow for the differentiation of puparia of the two fly species studied and could prove useful in future forensic entomological assessments.

The surface ultrastructure of all larval instars of Chrysomya rufifacies (Macquart) is described by means of scanning electron microscopy (SEM). Morphological changes were greatest from the first to the second instar, but less from the second to the third instar. Most of these changes involved the structure of the anterior spiracle, posterior spiracle, integument of the body, and mouthhooks. Modification of the mouthhooks, especially in the third instar, are helpful in explaining the ferocious feeding ability of the older maggots. The common name of "hairy-maggot" for C. rufifacies is only appropriate for the second and third instars because of their elongated tubercles along the body, whereas this name is not descriptive of the first instar that lack tubercles.

Sb doped ZnO nanostructures were synthesized by an ultrasonic-assisted method. Effect of Sb dopant on the structure, morphology, and composition of as-synthesized Sb doped ZnO nanostructures was investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray (EDX) spectroscopy, and transmission electron microscopy (TEM). All samples were identified to wurtzite hexagonal ZnO structure. UV-visible spectra of the as-synthesized 3% Sb doped ZnO sample exhibit broad absorption bands at around 343 nm which is blue shift of 373 nm of pure ZnO. The photocatalytic activity was tested by decolorization of methylene blue (MB) solution under UV light. After 300 min irradiation, the degradation efficiencies were 56, 90, and 95% for ZnO, 1% Sb doped ZnO, and 3% Sb doped ZnO, respectively. The 3% Sb doped ZnO shows the highest photocatalytic activity than any other samples.

Undoped and Ce doped Bi2MoO6samples were synthesized by hydrothermal reaction at 180°C for 20 h. Phase, morphology, atomic vibration, and optical properties were characterized by X-ray powder diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Raman spectrophotometry, Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), selected area electron diffraction (SAED), and UV-visible spectroscopy. In this research, the products were orthorhombic Bi2MoO6nanoplates with the growth direction along the [0b0], including the asymmetric and symmetric stretching and bending modes of Bi–O and Mo–O. Undoped and Ce doped Bi2MoO6samples show a strong absorption in the UV region.

The pH effect of the precursor solutions on the phase, morphologies, and photocatalytic activity of Bi2MoO6synthesized by a hydrothermal reaction at 180°C for 20 h was investigated. X-ray powder diffraction (XRD), Raman spectroscopy, Fourier transform infrared (FTIR) spectrometry, scanning electron microscopy (SEM), and transmission electron microscopy (TEM) revealed the presence of pure orthorhombic well-crystallizedγ-Bi2MoO6nanoplates, including the symmetric (A1g) and asymmetric (A2u) stretching vibrations of the MoO6octahedrons involving the motion of apical oxygen atoms. The photocatalytic activity of Bi2MoO6nanoplates at the pH 6 determined via the decomposition of rhodamine-B (RhB) organic dye was the highest at 98.66% decolorization under Xe light irradiation.

Nanoparticles of the title compounds are prepared from mixtures of Ca(NO3)2 or Sr(NO3)2 and Na2MoO4 or Na2WO4 dissolved in ethylene glycol (30 °C, 24 h) and characterized by XRD, TEM, FTIR, Raman, UV/VIS, and photoluminescence spectroscopy.

Morphology of the alimentary canal of the mature third instar larva of the blow fly, Chrysomya megacephala (F.), was examined using light, scanning, and transmission electron microscopy. Salivary structures consist of a single median deferent duct that bifurcates into efferent ducts connected to paired, tubular salivary glands comprised of closely packed conical-shaped epithelial cells with large nuclei. The crop occurs as a large, swollen diverticulum of the digestive tube and is lined internally with convoluted cuticle (epicuticle and endocuticle). The esophagus is a simple, straight tube internally lined with cuticle and externally encompassed by muscle fibers. The cardia is a bulb-like structure composed of anterior foregut tissue and posterior midgut tissue from which the peritrophic membrane (PM) is produced. The midgut begins within the cardia which is flanked posteriorly by four tubular gastric caeca that are lined internally with four to five layers of cuboidal epithelial cells bearing microvilli. Midgut tissue is lined with simple cuboidal epithelium whose cells are filled with numerous secretory granules and possessed long microvilli facing the lumen. A peritrophic membrane is contained within the midgut lumen. The larval hindgut consists of the pylorus, Malpighian tubules, ileum, colon, rectum, and anus, posteriorly. The pylorus is characterized by a single layer of epithelial cells encircled by a muscular layer and the presence of PM within the lumen. Malpighian tubules each diverge into two tubular structures totalling four long tubules of long chained cuboidal cells bearing microvilli internally. The wall of the ileum is comprised primarily of a monolayer of cuboidal epithelial cells with large oval nuclei and more intense muscular fibers surrounding the periphery. A cuticular layer surrounds the lumen containing the PM. This inner cuticle consists of a thin epicuticle that is electron-dense; whereas, the endocuticle is much thicker but less electron-dense. Myo-epithelial cells are dense in the anal region, where the PM persists.

This article presents Chrysomya nigripes Aubertin as a blow fly species of forensic importance in Thailand, and morphological observation of fly puparia using scanning electron microscopy (SEM). Morphologically, we focused on the characteristics of puparia used to accurately identify fly species. Numerous puparia of C. nigripes were found aggregated, adhering side by side, on the tibia of a skeletonized corpse, which was recovered from a forested area of Chiang Mai, northern Thailand. In the triangular shape of the anterior end of the puparia, three thoracic segments and broad hairy patches beginning dorsolaterally at the sixth segments were distinguishing characteristics. This study, showing pupariation of the flies along the bone of a corpse as well as morphological features, provides important guidance in identifying C. nigripes puparia. A key to differentiate puparia of C. nigripes from the other flies of forensic importance in Thailand is given.

The surface ultrastructure of all larval instars of Chrysomya rufifacies (Macquart) is described by means of scanning electron microscopy (SEM). Morphological changes were greatest from the first to the second instar, but less from the second to the third instar. Most of these changes involved the structure of the anterior spiracle, posterior spiracle, integument of the body, and mouthhooks. Modification of the mouthhooks, especially in the third instar, are helpful in explaining the ferocious feeding ability of the older maggots. The common name of "hairy-maggot" for C. rufifacies is only appropriate for the second and third instars because of their elongated tubercles along the body, whereas this name is not descriptive of the first instar that lack tubercles.

The larval morphology of Chrysomya megacephala (Fabricius) is presented using scanning electron microscopy (SEM). Extreme similarity of this species to Chrysomya rufifacies (Macquart), a species usually found concurrently inhabiting decomposing human corpses in Thailand, is seen only in the first-instar larvae. The relative thickness of the branches of the posterior spiracular hairs in these species could be used to differentiate them in this developmental stage. In contrast, the "hairy" appearance of C. rufifacies allows second- and third-instar larvae to be easily distinguished. Results of this study should help in future endeavors to differentiate C. megacephala from other larvae found in decomposing human corpses in Thailand.

The fine structure of the eggshell of blow fly, Lucilia cuprina (Wiedemann) (Diptera: Calliphoridae), was examined using scanning and transmission electron microscopy. Eggs, 1.09+/-0.07 mm in length and 0.25+/-0.05 mm in width, bore a relatively wide plastron that extending along almost the entire length. The polygonal pattern of chorionic sculpture was indistinct. The ultrathin section indicated a multi-layered eggshell having an exochorion, outer endochorion, pillars, an inner endochorion, innermost chorionic layer, and a wax layer. This study provides new information about the fine morphology of blow flies eggs. A key to differentiate the eggs of forensically important flies in Thailand is given.