We have carried out a survey of the north and south ecliptic poles, EP-N and EP-S, respectively, with the Spitzer Space Telescope and the Wide-field Infrared Survey Explorer (WISE). The primary objective was to cross-calibrate WISE with the Spitzer and Midcourse Space Experiment (MSX) photometric systems by developing a set of calibration stars that are common to these infrared missions. The ecliptic poles were continuous viewing zones for WISE due to its polar-crossing orbit, making these areas ideal for both absolute and internal calibrations. The Spitzer IRAC and MIPS imaging survey covers a complete area of 0.40 deg 2 for the EP-N and 1.28 deg 2 for the EP-S. WISE observed the whole sky in four mid-infrared bands, 3.4, 4.6, 12, and 22 μm, during its eight-month cryogenic mission, including several hundred ecliptic polar passages; here we report on the highest coverage depths achieved by WISE, an area of ∼1.5 deg 2 for both poles. Located close to the center of the EP-N, the Sy-2 galaxy NGC 6552 conveniently functions as a standard calibrator to measure the red response of the 22 μm channel of WISE. Observations from Spitzer-IRAC/MIPS/IRS-LL and WISE show that the galaxy has a strong red color in the mid-infrared due to star-formation and the presence of an active galactic nucleus (AGN), while over a baseline >1 year the mid-IR photometry of NGC 6552 is shown to vary at a level less than 2%. Combining NGC 6552 with the standard calibrator stars, the achieved photometric accuracy of the WISE calibration, relative to the Spitzer and MSX systems, is 2.4%, 2.8%, 4.5%, and 5.7% for W1 (3.4 μm), W2 (4.6 μm), W3 (12 μm), and W4 (22 μm), respectively. The WISE photometry is internally stable to better than 0.1% over the cryogenic lifetime of the mission. The secondary objective of the Spitzer-WISE Survey was to explore the poles at greater flux-level depths, exploiting the higher angular resolution Spitzer observations and the exceptionally deep (in total coverage) WISE observations that potentially reach down to the confusion limit of the survey. The rich Spitzer and WISE data sets were used to study the Galactic and extragalactic populations through source counts, color-magnitude and color-color diagrams. As an example of what the data sets facilitate, we have separated stars from galaxies, delineated normal galaxies from power-law-dominated AGNs, and reported on the different fractions of extragalactic populations. In the EP-N, we find an AGN source density of ∼260 deg −2 to a 12 μm depth of 115 μJy, representing 15% of the total extragalactic population to this depth, similar to what has been observed for low-luminosity AGNs in other fields.

Wide band-gap semiconductorzinc oxide nanoclusters have been prepared in the channels of MCM-41 materials by functionalizing the MCM-41 with ethylenediamine groups, absorbing zinc cations, and calcinating at high temperatures. The products have been characterized by XRD, TEM, EDS, nitrogen adsorption and desorption, and UV−vis and PL spectroscopies. ZnO clusters were mostly confined and dispersed in the pores of mesoporous hosts. No large ZnO particles on the external surfaces have been detected. A massive blue-shift in UV−vis absorption spectra has been observed and large band increase can be expected. The nature of the PL spectrum has been attributed to the defects related to oxygen vacancies. In addition, the assembly of cobalt, nickel, and copper oxides inside MCM-41 materials has also been tried by this scheme, but at the moment, only the cobalt oxide can be prepared with good results. Unfortunately, noble metals have usually grown into large particles on the outside surface of MCM-41 by this scheme, e.g., a lot of silver particles with sizes much larger than the pore diameter of MCM-41 host have been obtained. However, the explanation is not yet clear.

A facile method has been developed to synthesize nanoporous manganese and nickel oxides with polyhedron particle morphologies, high surface areas and narrow pore distributions by controlled thermal decomposition of the oxalate precursors. This method can be extended to using other kinds of salt precursors to prepare a series of nanoporous metal oxides. The heating rate, calcination temperature and controlled particle size of the oxalate precursors are important factors to get well‐defined pore structures. XRD, TG‐DTA, TEM, SEM, XPS, wet chemical titration and N2 sorption isotherm techniques are employed for morphology and structure characterizations. High surface area microporous manganese oxide (283 m2 g−1) and mesoporous nickel oxide (179 m2 g−1) with narrow pore distribution at around 1.0 nm and 6.0 nm, respectively, are obtained. Especially, we can tune the pore size of manganese oxides from microscope to mesoscope by controlling the thermal procedure. Electrochemical properties of manganese and nickel oxides are studied by cyclic voltammetry measurements in a mild aqueous electrolyte, which shows a high specific capacitance of 309 F g−1 of microporous manganese oxide and a moderately high specific capacitance of 165 F g−1 of mesoporous NiO due to their nanoporous structure, presenting the promising candidates for super capacitors (SC).

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Nanosized ZnS has been prepared inside MCM-41 hosts by two related schemes, both of which are derived from surface modification methods. The ZnS-containing MCM-41 samples with and without the functional groups (ethylenediamine groups in this case) were designated as ZnS-ED-MCM-41 and ZnS-MCM-41(cal), respectively. The ZnS-MCM-41 composites were characterized by powder X-ray diffraction patterns, transmission electron microscopy, energy disperse spectra, N 2 adsorption-desorption isotherms, UV-vis diffuse reflectance spectra, and photoluminescence (PL) spectra. The ZnS was mainly formed and retained in the channels of the MCM-41 host, and its growth was controlled by the channels. In contrast, the amount of ZnS on the external surface is much smaller. The existence of ZnS inside the MCM-41 hosts resulted in a considerable decrease in surface area, pore diameter, and pore volume, and a massive blue shift in the UV-vis spectra was observed. In comparison with the ZnS-MCM-41(cal) sample, a dramatic increase in PL emission for the ZnS-ED-MCM-41 sample was observed, which was suggested to arise from a strong interaction between the ZnS clusters and the organic component. The nature of the PL spectra has been tentatively attributed to the sulfur vacancies in the present experiment. Finally, the synthesis of other sulfides, such as CdS and CuS clusters, has also been explored inside the channels of the MCM-41 host.

Introduction: Entry into tertiary education is a critical juncture where adolescents proceed to adulthood. This study aimed to determine the prevalence of depression and anxiety, and factors associated with such symptoms, among university undergraduate students in Hong Kong. Methods: A cross-sectional questionnaire study was employed. A total of 1200 undergraduate students from eight University Grants Committee-funded universities were invited to complete three sets of questionnaires, including the 9-item patient health questionnaire for screening of depressive symptoms, the 7-item generalised anxiety disorder scale for screening of anxiety symptoms, and a sociodemographic questionnaire. Results: Among the valid responses (n=1119) analysed, 767 (68.5%) respondents indicated mild to severe depressive symptoms, which were associated with mild to severe anxiety symptoms. Several lifestyle and psychosocial variables, including regular exercise, self-confidence, satisfaction with academic performance, and optimism towards the future were inversely related with mild to severe depressive symptoms. A total of 599 (54.4%) respondents indicated mild to severe anxiety symptoms, which were associated with level of academic difficulty. Depression and anxiety among university students in Hong Kong New knowledge added by this study • Up to 9% of university students in Hong Kong exhibit moderately severe to severe depressive symptoms. • Up to 5.8% of university students in Hong Kong exhibit severe anxiety symptoms. • Respondents reporting regular exercise, higher self-confidence, and better satisfaction with both friendship and academic performance had fewer depressive and anxiety symptoms. Implications for clinical practice or policy • Health care workers and organisations such as universities should be aware of potential depression and anxiety among university undergraduate students. • Adolescents and young adults in Hong Kong should be educated, to raise social awareness of depression and anxiety among university undergraduate students.

In this paper, we present an easy template-free route to synthesize mesoporous Fe 2 O 3 with a high surface area of 111 m 2 /g and narrow pore distribution at 4.4 nm. This strategy has significant advantages comparing to the traditional templating routes in performance/price ratio and flexibility of procedures, and the mesoporous materials can be manufactured in quantity scale. The prepared mesoporous materials were used as an adsorbent to dispose of the Congo red containing wastewater, and they exhibited more favorable adsorptive properties than the commercial metal oxide powders with low surface area.

Direct synthesis (co‐condensation reaction) and post‐synthesis reaction (grafting) are combined for the first time to efficiently fabricate bifunctionalized ordered mesoporous materials (OMMs). Ethylenediamine‐containing OMMs (ED‐MCM‐41) were first synthesized via direct synthesis and then further modified by the phenyl (PH) group in a supercritical fluid (SCF) medium via grafting reaction, resulting in OMMs with ED and PH groups (PH‐ED‐MCM‐41). X‐ray diffraction (XRD) patterns, N2 sorption properties, transmission electron microscopy (TEM), 29Si and 13C magic angle spinning (MAS) NMR, chemical analysis, and hydrothermal treatment were used to characterize the bifunctionalized materials. Experiments show that bifunctionalized OMMs can be efficiently prepared by modifying the directly synthesized monofunctionalized OMMs via grafting reaction in a supercritical fluid medium. Both functional groups are distributed uniformly at the surfaces. The advantage of bifunctionalized OMMs over monofunctionalized OMMs was illustrated by introducing thiol groups into ED‐MCM‐41 materials and the subsequent formation of CdS nanocrystals inside thiol‐ and ED‐functionalized MCM‐41 (HS‐ED‐MC‐41). Because of the variety of the functional groups that can be introduced into OMMs by direct synthesis or post‐synthesis reaction, it is expected that the present strategy could provide a generally applicable approach to the design of OMMs with two functional groups.