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The alkylation of phenol with methanol was studied in vapor phase over 5 wt% cerium supported on HZSM-5 catalyst prepared by three different methods, such as impregnation, ball mixing and solid-state ion-exchange. The catalytic activities are tested in a fixed-bed reactor, and the physicochemical properties of the catalyst are characterized with X-ray powder diffraction, scanning electron microscope, nitrogen physical sorption, Fourier Transform Infrared Spectrometer, Infrared spectra of pyridine adsorption, X-ray photoelectron spectroscopy and temperature-programmed desorption of ammonia. It was found that the dispersion form of cerium was greatly affected by the preparation method, and difference in acidity affects catalytic performance in the alkylation reaction of phenol and methanol. Ball milling method generated greater amount of strong Brønsted acidic sites and lower specific surface area than other catalysts, which led to higher carbon deposition rate and lower catalyst activity. The catalyst prepared by impregnation method yields higher Lewis acid concentration (2.09 μmol/g) and more chemisorbed oxygen due to the increased Ce3+ concentration in the lattice, resulted in an improved o-cresol selectivity of 48%. Furthermore, the catalyst prepared by solid-phase ion-exchange method produces a catalyst with appropriate B/L ratio of 60.6 and large specific surface area of 389.0 m2/g, which yields the highest phenol conversion of 23%. [ABSTRACT FROM AUTHOR]

The South China Sea (SCS) is a highly semi-enclosed marginal sea located in the East Asian monsoon region. This paper proposes interesting aspects of the unique feature of the SCS waves in response to tropical cyclone's passage when large-scale winter monsoon winds prevail. We use the wave model WaveWatch III to study the wave characteristics of typhoon Durian (2006) passing over the middle of SCS in early December 2006, and state the new understanding acquired in the aspects of the tropical cyclone generated waves in the SCS during winter monsoon surge. In light of this, the role of the large-scale NE monsoon winds on winter typhoon wave field characteristics in the SCS are highlighted by conducting sensitivity experiments with and without the NE monsoon winds. The NE monsoon winds weakly affect the SWH field near the typhoon track and strongly away from the track, especially in the deep water area of the northern SCS where the NE monsoon winds produce high waves. Comparisons between the two experiments show the effect of the NE monsoon winds on the directional wave spectra in the SCS, suggesting that the monsoon-generated swells do not decay and remain throughout the typhoon period. [ABSTRACT FROM AUTHOR]

Fresh onions (Allium cepa L.) emit volatile organic compounds (VOCs) naturally in very low concentrations. The aim of the present study was to determine the emission rate of low-boiling VOCs from healthy and naturally infected onion bulbs at 4, 15, and 25 °C and to evaluate the applicability of the VOC method to monitor quality changes during 12 weeks of storage of two cultivars ('Hystand' and 'Hoza') of yellow onions. VOCs were extracted from the headspace of bulbs by solid phase micro-extraction (SPME) up to 5 times during storage and analyzed by gas chromatography–mass spectrometry (GC–MS). A total of twenty-nine compounds were measured and twenty-seven of these were identified while thirteen were reported for the first time from yellow onion bulbs. Acetone (0.10–18.0 nmol kg−1 day−1), dimethyl disulfide (0.12–18.9 nmol kg−1 day−1) and hexanal (0.05–4.40 nmol kg−1 day−1) were among the most abundant volatiles emitted from healthy bulbs. The concentration of these compounds as well as the total volatiles decreased with time in storage. However, microbial infection resulted in higher emission of propene, carbon disulfide, isoprene, pentane, 2-methylfuran, 3-methylfuran, 1-propenethiol, hexane, and methyl propyl sulfide, indicating that VOC emission may be used as an indicator to monitor natural senescence and decay of stored onion bulbs. [ABSTRACT FROM AUTHOR]

Based on coastal tide level, satellite altimetry, and sea surface temperature (SST) data of offshore areas of China’s coast and the equatorial Pacific Ocean, the regional characteristics of the effects of the El Niño-Southern Oscillation (ENSO) on the sea level in the China Sea were investigated. Singular value decomposition results show a significant teleconnection between the sea level in the China Sea and the SST of the tropical Pacific Ocean; the correlation coefficient decreases from south to north. Data from tide gauges along China’s coast show that the seasonal sea-level variations are significantly correlated with the ENSO. In addition, China’s coast was divided into three regions based on distinctive regional characteristics. Results obtained show that the annual amplitude of sea level was low during El Niño developing years, and especially so during the El Niño year. The ENSO intensity determined the response intensity of the annual amplitude of the sea level. The response region (amplitude) was relatively large for strong ENSO intensities. Significant oscillation periods at a timescale of 4-7 years existed in the sea level of the three regions. The largest amplitude of oscillation was 1.5 cm, which was the fluctuation with the 7-year period in the South China Sea. The largest amplitude of oscillation in the East China Sea was about 1.3 cm. The amplitude of oscillation with the 6-year period in the Bohai Sea and Yellow Sea was the smallest (less than 1 cm). [ABSTRACT FROM AUTHOR]

As a natural agent for chemotherapy, deguelin remarkably suppresses proliferation in numerous solid cancers. Nevertheless, the molecular mechanisms of its suppression are still insufficient. In our research, it was revealed that deguelin induced cell death of lung cancer cells (LCCs) by triggering expression of PUMA. Deguelin triggered PUMA induction independently of p53 via suppression of PI3K/AKT pathway, therefore stimulating Foxo3a to bind with PUMA promoter and stimulate its transcription. Subsequent to activation, PUMA motivated Bax as well as the intrinsic mitochondrial cell death pathway. Removal of PUMA from LCC cells led to deguelin resistance, suggesting deguelin-induced cell death was modulated by PUMA. Furthermore, we demonstrated that deguelin enhanced the chemotherapeutic sensitivity of doxorubicin in vitro and in vivo, which were associated with potentiated PUMA induction. Taken together, these results establish a critical role of PUMA in mediating the anticancer effects of deguelin in lung cancer cells and provide the rationale for clinical evaluation. [ABSTRACT FROM AUTHOR]