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WO3-decorated TiO2 nanotube arrays were successfully synthesized using an in situ anodization method in ethylene glycol electrolyte with dissolved H2O2 and ammonium fluoride in amounts ranging from 0 to 0.5 wt %. Anodization was carried out at a voltage of 40 V for a duration of 60 min. By using the less stable tungsten as the cathode material instead of the conventionally used platinum electrode, tungsten will form dissolved ions (W6+) in the electrolyte which will then move toward the titanium foil and form a coherent deposit on the titanium foil. The fluoride ion content was controlled to determine the optimum chemical dissolution rate of TiO2 during anodization to produce a uniform nanotubular structure of TiO2 film. Nanotube arrays were then characterized using FESEM, EDAX, XRD, as well as Raman spectroscopy. Based on the FESEM images obtained, nanotube arrays with an average pore diameter of up to 65 nm and a length of 1.8 µm were produced. The tungsten element in the samples was confirmed by EDAX results which showed varying tungsten content from 0.22 to 2.30 at%. XRD and Raman results showed the anatase phase of TiO2 after calcination at 400 °C for 4 h in air atmosphere. The mercury removal efficiency of the nanotube arrays was investigated by photoirradiating samples dipped in mercury chloride solution with TUV (Tube ultraviolet) 96W UV-B Germicidal light. The nanotubes with the highest aspect ratio (15.9) and geometric surface area factor (92.0) exhibited the best mercury removal performance due to a larger active surface area, which enables more Hg2+ to adsorb onto the catalyst surface to undergo reduction to Hg0. The incorporation of WO3 species onto TiO2 nanotubes also improved the mercury removal performance due to improved charge separation and decreased charge carrier recombination because of the charge transfer from the conduction band of TiO2 to the conduction band of WO3.

High aspect ratio of WO3-loaded TiO2 nanotube arrays have been successfully synthesized using the electrochemical anodization method in an ethylene glycol electrolyte containing 0.5 wt% ammonium fluoride in a range of applied voltage of 10–40 V for 30 min. The novelty of this research works in the one-step formation of WO3-loaded TiO2 nanotube arrays composite film by using tungsten as the cathode material instead of the conventionally used platinum electrode. As compared with platinum, tungsten metal has lower stability, forming dissolved ions (W6+) in the electrolyte. The W6+ ions then move towards the titanium foil and form a coherent deposit on titanium foil. By controlling the oxidation rate and chemical dissolution rate of TiO2 during the electrochemical anodization, the nanotubular structure of TiO2 film could be achieved. In the present study, nanotube arrays were characterized using FESEM, EDAX, XRD, as well as Raman spectroscopy. Based on the results obtained, nanotube arrays with average pore diameter of up to 74 nm and length of 1.6 µm were produced. EDAX confirmed the presence of tungsten element within the nanotube arrays which varied in content from 1.06 at% to 3.29 at%. The photocatalytic activity of the nanotube arrays was then investigated using methyl orange degradation under TUV 96W UV-B Germicidal light irradiation. The nanotube with the highest aspect ratio, geometric surface area factor and at% of tungsten exhibited the highest photocatalytic activity due to more photo-induced electron-hole pairs generated by the larger surface area and because WO3 improves charge separation, reduces charge carrier recombination and increases charge carrier lifetime via accumulation of electrons and holes in the two different metal oxide semiconductor components.

The nano-scale magnetite iron oxide particles have been synthesised by a facile precipitation method. Magnetite iron oxide nanoparticles were synthesised in a bath with electrolytes composed of 0·10 M of iron (II) chloride with 0·45 M of sodium hydroxide at different reaction temperatures under oxidising environment. In the present study, the influence of reaction temperatures (30, 45 and 80°C) on the morphology, particle size and crystallinity of the iron oxide particles were investigated in detail. Based on the Malvern Zetasizer analysis, the iron oxide particles with variable size from ∼250 to ∼70 nm could be achieved when increasing the reaction temperature up to 80°C. The magnetite phase of iron oxide particles was determined by using X-ray diffraction analysis. In addition, field emission scanning electron microscopy micrographs were further affirmed that our synthesised iron oxide particles were in nano-scale with a spherical shape. It was found that the high reaction temperature is helpful...

One-dimensional (1D) titanate nanotubes (TNT) were successfully synthesized using alkaline hydrothermal treatment of commercial TiO2nanopowders in a Teflon lined stainless steel autoclave at 150°C. The minimum time required for the formation of the titanate nanotubes was 9 h significantly. After the hydrothermal processing, the layered titanate was washed with acid and water in order to control the amount of Na+ions remaining in the sample solutions. In this study, the effect of different reaction durations in a range of 3 h to 24 h on the formation of nanotubes was carried out. As the reaction duration is extended, the changes in structure from particle to tubular shapes of alkaline treated TiO2were obtained via scanning electron microscope (SEM). Also, the significant impact on the phase transformation and crystal structure of TNT was characterized through XRD and Raman analysis. Indeed, the photocatalytic activity of TNT was investigated through the degradation of methyl orange aqueous solution under the ultraviolet light irradiation. As a result, TNT with reaction duration at 6 h has a better photocatalytic performance than other samples which was correlated to the higher crystallinity of the samples as shown in XRD patterns.

Background: Measures of body size at birth are widely used for the evaluation of prenatal growth but limitations exist in their interpretation. Objective: To establish the percentile curves for the six common anthropometric indices (PI: ponderal index, BMI: body mass index, THR: thigh circumference/head circumference ratio, MAC/OFC: mid-arm circumference/head circumference, W/OFC: weight/head circumference, and W/L: weight/length) and determine the best anthropometric index for evaluating intrauterine nutritional status in Chinese neonates. Methods: A prospective cross-sectional anthropometric study was carried out. The anthropometric measurements were performed according to the Hall’s guidelines within 48 h of birth. Results: 10,226 infants (5,422 males, 4,804 females) with gestation 28–42 weeks from 12 hospitals were included for analysis. All of the six anthropometric indices correlated well with total skinfold thickness (T-SF, the sum of triceps skinfold thickness and subscapular skinfold thickness; p < 0.0001). Among the six anthropometric indices, W/L showed the highest correlation coefficient with T-SF (r = 0.622; p < 0.0001 in whole group, r = 0.653; p < 0.0001 in preterm infants, r = 0.612; p < 0.0001 in term infants). Conclusion: The present study establishes the gender-specific reference curves for the six important anthropometric indices in Chinese infants. W/L is a readily available index at birth that reflects the intrauterine nutritional state.

UNLABELLED Skinfold thickness is a validated parameter of subcutaneous fat accumulation. Data on triceps and subscapular skinfold thicknesses were collected from 10,043 (5318 males, 4725 females) singletons at 12 hospitals with gestation 31-42 wk. The LMS method using maximum penalized likelihood was used to perform model fitting of the anthropometric centiles for these parameters. Both triceps and subscapular skinfold thicknesses were greater in girls than in boys. Racial differences were found when comparing with other populations. The triceps subscapular skinfold thicknesses of Chinese infants were significantly lower than those of US white infants but larger than those of African-American infants, Israeli infants, Spanish infants and Indian infants. CONCLUSION This study provides the first set of references for the triceps and subscapular skinfold thicknesses of Chinese infants by gestation and gender. These data are helpful in determining the nutritional status of infants at birth and in assessing the postnatal growth of Chinese infants.

Careful examination and assessment of penile length in the newborn is important because micropenis is associated with hypothalamic disorders. This prospective cross-sectional study was designed to establish the norm of penile length for term Hong Kong Chinese newborns. 4,628 full-term healthy male newborns were enrolled in the study. Penile length was measured from pubic ramus to the tip of the glans penis by placing the end of a straight edge ruler against the pubic ramus. A gestation-associated graph of 3rd, 10th, 25th, 50th, 75th, 90th and 97th centiles for the penile length was created. The penile length was significantly correlated with gestational age, birth weight and body length. When compared with published data for other populations, Hong Kong newborns have significantly shorter penile length. The norm of the penile length is useful in diagnostic and therapeutics for the ethnic Chinese male newborns.

Few studies have investigated the velocities of fetal growth. The aim of the present study was to determine the pattern of ‘fetal’ growth velocities in a Chinese population. The gestation-specific measurements of the body weight, body length and head circumference in a representative sample of 5,045 male and 4,484 female newborns delivered between 26 and 42 weeks of gestation at 12 hospitals in Hong Kong were obtained. Peak growth velocity occurred before 30 weeks of gestation for head circumference, at week 30 for length and at week 30 for weight. When compared with data obtained from a French population, a significant difference in the growth velocity for body weight was observed below 32 weeks between French and Chinese infants, suggesting an ethnic difference in fetal growth of this parameter.

A 5-year territory-wide retrospective survey of invasive Haemophilus influenzae type b (Hib) diseases in Hong Kong established that the annual incidence for children5 years old was 2.7 per 100000 [95% confidence interval (CI), 2.0 to 3.5]. However, the corresponding annual incidence in Vietnamese refugees in Hong Kong was 42.7 per 100000 (95% CI 17.2 to 87.9), giving a relative risk of 18.5 (95% CI 8.3 to 41.0). The nasopharyngeal carriage rate of Hib was zero in 621 healthy Chinese children and 1.3% (95% CI 0.04 to 2.63%) in 300 healthy Vietnamese refugees 2 months to 5 years old in Hong Kong. The corresponding carriage rate of nontypable H. influenzae was 5.8% (95% CI 1.4 to 7.6%) in Chinese and 65.4% (95% CI 58.9 to 69.8) in Vietnamese. In a larger study of 1812 healthy Chinese children between 6 months and 5 years of age investigated by throat swabs, again no Hib was isolated but 141 children (7.8%) were found to be carriers of nontype b H. influenzae. In a study of 596 healthy Chinese children and adults, 25% had the protective level of anti-Hib antibody of0.15 microg/ml by 1 year and 90% had reached0.15 microg/ml by 6 years of age. There was some evidence that these "natural" antibodies against Hib in Hong Kong Chinese were cross-reacting antibodies against antigens on other encapsulated bacteria.