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The new design strategy will provide the possibility for preparing a dynamic sensor by employing the inhibition of C = N isomerization. In this work, the functional probe 4-(1 H-imidazo [4,5-f] [1,10]-phenanthrolin-2-yl) benzaldehyde oxime (compound 4) has been synthesized and such molecule gives rise to blue emission. Due to the incorporation of hypochlorite, the oxime group can be oxidized to the structure of aldehyde. As a result, the molecular motif exhibits sharp emission change from blue to green due to the addition of hypochlorite with enough sensitivity and selectivity (detection limit = 53 nM, linear range 0.5-8.0 µM). It has also been used for monitoring ClO− by employing solution color change and the absorption signal difference could effectively rule out the effects of interference species. To our knowledge, it will be the first case of a highly selective hypochlorite sensor derived from oxime isomerization reaction based on phenanthroline backbone. [ABSTRACT FROM AUTHOR]

The arid and semi-arid (ASA) region of Asia occupies a large area in the middle latitudes of the Northern Hemisphere, of which the main body is the ASA region of Central and East Asia (CEA). In this region, the climate is fragile and the environment is sensitive. The eastern part of the ASA region of CEA is located in the marginal zone of the East Asian monsoon and is jointly influenced by westerly circulation and the monsoon system, while in the western part of the ASA of CEA, the climate is mainly controlled by westerly circulation. To understand and predict the climate over this region, it is necessary to investigate the influence of general circulation on the climate system over the ASA region of CEA. In this paper, recent progress in understanding the relationship between the general circulation and climate change over the ASA region is systematically reviewed. Previous studies have demonstrated that atmospheric circulation represents a significant factor in climate change over the ASA region of CEA. In the years with a strong East Asian summer monsoon, the water vapor flux increases and precipitation is abundant in the southeastern part of Northwest China. The opposite situation occurs in years when the East Asian summer monsoon is weak. With the weakening of the East Asian summer monsoon, the climate tends to dry over the semi-arid region located in the monsoon marginal zone. Recently, owing to the strengthening of the South Asian monsoon, more water vapor has been transported to the ASA region of Asia. The Plateau summer monsoon intensity and the precipitation in summer exhibit a significant positive correlation in Central Asia but a negative correlation in North China and Mongolia. A significant positive correlation also exists between the westerly index and the temperature over the arid region of CEA. The change in the westerly circulation may be the main factor affecting precipitation over the arid region of Central Asia. [ABSTRACT FROM AUTHOR]

In this study, a combination of satellite observations and reanalysis datasets is used to analyze the spatiotemporal distribution, classification and source of pollutants over the eastern slope of the Tibetan Plateau (ESTP). The aerosol optical depth (AOD) over the ESTP is extremely large and even larger than some important industrialized regions and deserts. The main aerosol component over the ESTP is sulfate, followed by carbonaceous and dust aerosols. Local emissions related to human activity directly contribute to the accumulation of sulfate and carbonaceous aerosols over the Sichuan Basin. In addition, in spring, abundant carbonaceous aerosols emitted from forest, grassland and savanna fires in Southeast Asia can be transported by the prevailing southwesterly wind to southern China and the ESTP. The dust AOD over the ESTP peaks in spring because of the transport from the Taklimakan and Gobi deserts. Additionally, the high aerosol loading over the ESTP is also directly related to the meteorological background. Due to the special topography, the terrain-driven circulation can trap aerosols in the Sichuan Basin and these aerosols can climb along the ESTP due to the perennial updraft. The aerosol loading is lowest in summer because of effective wet deposition induced by the strong precipitation and better dispersion conditions due to the larger vertical temperature gradients and ascending air movement enhanced by the plateau heat pump effect. In contrast, the aerosol loading is greatest in winter. Abundant anthropogenic aerosols over the ESTP may generate some climatic and environmental risks and consequently greatly influence the downstream regions. [ABSTRACT FROM AUTHOR]

With the global warming slowdown in the twenty‐first century, a huge discrepancy in regional climate warming has been identified over the main region of the Tibetan Plateau (TP). Compared with the +0.04 °C/decade warming from 1961 to 1999, the warming greatly accelerated for the period 2000–2015 at a rate of +0.30 °C/decade. During the same period, warming in the cold season (November to March) was more pronounced than in the warm season (May to September) over the TP. The results also indicated that the middle‐level cloud (middle cloud) decreased (−0.359%/year), while the high‐level cloud (high cloud) increased (+0.241%/year) over almost all the TP during the cold season. Further analysis showed positive net cloud radiative forcing over the western TP from 2000–2015, that is, a heating effect of clouds, especially in the cold season. Combining the trends of the increase in high cloud and the decrease in middle cloud over most parts of the TP, the decreased albedo effect of middle cloud and the increased longwave greenhouse effect of high cloud may have partially contributed to the sustained warming, especially in the cold season from 2000 to 2015. Meanwhile, the results showed that the warming rate and cloud area fraction changes were significantly amplified with elevation. The analysis based on a model of Coupled Model Intercomparison Project Phase 5 shows that the decreased middle cloud plays more important role than the increased high cloud in modulating the enhanced warming over the TP, especially in the cold season. The percentage of SAT caused by longwave CRF (red bar) and shortwave CRF (blue bar) to total SAT derived from CNRM‐CM5 model of CMIP5 over the TP for cold season in the period of 2000–2005. [ABSTRACT FROM AUTHOR]