The climatic and environmental effects of atmospheric aerosols are a hot topic in global science community, and radiative properties of the aerosols are one of the important parameters in assessing climatic change. Here we studied the black carbon concentration and absorption coefficient measured with aethalometers, scattering coefficient measured with nephelometers, and single scattering albedo derived at an atmospheric composition watch station in Guangzhou from 2004 to 2007. Our main results are as follows. The data of black carbon concentration and absorption coefficients measured with instruments cannot be directly used until they are measured in parallel with internationally accepted instruments for comparison, calibration, and reduction. After evaluation of the data, the result shows that the monthly mean of BC concentration varies 3.1-14.8 μg·m −3 and the concentration decreases by about 1 μg·m −3 in average over the four years; It is higher in the dry season with a multi-year mean of 8.9 μg/m 3 and lower in the rainy season with a multi-year mean of 8.0 μg·m −3 ; The extreme maximum of monthly mean concentration occurred in December 2004 and extreme minimum in July 2007, and a 4-year mean is 8.4 μg·m −3 . It is also shown that monthly mean scattering coefficient derived varies 129 -565 Mm −1 , monthly mean absorption coefficient 32-139 Mm −1 , and monthly mean single scattering albedo 0.71-0.91, with annual mean values of 0.80, 0.82, 0.79 and 0.84 for 2004, 2005, 2006 and 2007,respectively. Three instruments were used to take simultaneous measurements of BC in PM 10 , PM 2.5 , and PM 1 and the results showed that PM 2.5 took up about 90% of PM 10 and PM 1 accounted for about 68% of PM 2.5 , and BC aerosols are mainly present in fine particulates. The variability of BC concentrations is quite consistent between the Nancun station (141 m above sea level) and the Panyu station (13 m above sea level), which are 8 km apart from each other. The concentration in higher altitude station (Panyu) is consistently lower than the lower altitude station (Nancun), and the difference of annual mean is about 4 μg·m −3 .

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Ready to direct: Crystalline selenidostannates were synthesized in imidazolium‐based ionic liquids with a small amount of hydrazine monohydrate as additive (see scheme). They are the first open‐framework chalcogenides structurally directed by imidazolium cations and are inaccessible by traditional methods.

The CO-bridged anions [(µ-RE)(µ-CO)Fe 2 (CO) 6 ] -reacted with S 8 to form the sulfur-centered anions (µ-RE)(µ-S -)Fe 2 (CO) 6 (4; E ) S, Se), whereas reaction of the anions with Se 8 yielded the selenium-centered anions (µ-RE)(µ-Se -)Fe 2 (CO) 6 (6; E ) S, Se). Interestingly, reaction of 4 with SO 2 Cl 2 afforded the S-S-bonded clusters [(µ-RE)Fe 2 (CO) 6 ] 2 (µ-S-S) (5), whereas reaction of 6 with SO 2 Cl 2 produced the µ 4 -Se clusters [(µ-RE)Fe 2 (CO) 6 ] 2 (µ 4 -Se) (8); clusters 8 could also be produced by the action of anions 6 on succinoyl chloride or p-phthaloyl chloride, while the µ 4 -S clusters [(µ-RE)Fe 2 (CO) 6 ] 2 (µ 4 -S) (9) were generated by reaction of anions 4 with the above organic bis acid chlorides under similar conditions. Also, reaction of 4 (E ) S) with p-MeC 6 H 4 SO 2 Cl gave the µ 4 -S clusters [(µ-RE)Fe 2 (CO) 6 ] 2 (µ 4 -S) (9; E ) S) and the expected Fe 2 S 2 butterfly clusters (µ-RE)(µ-p-MeC 6 H 4 SO 2 S)Fe 2 (CO) 6 ( 10), whereas anion 6 reacted with p-MeC 6 H 4 SO 2 Cl to afford the unexpected SdO-bridged complexes (µ-RE)(µ-p-MeC 6 H 4 SO 2 )Fe 2 (CO) 6 (11) and µ 4 -Se clusters 8. Clusters 11 could be also prepared through direct reaction of the precursor of 6, i.e. [(µ-RE)(µ-CO)Fe 2 (CO) 6 ] -, with p-MeC 6 H 4 SO 2 Cl. For some of these reactions the mechanisms were preliminarily proposed. The structures of 15 new cluster compounds have been characterized by C/H analysis and IR, 1 H NMR, and MS spectroscopy; those of [(µ-EtS)Fe 2 (CO) 6 ] 2 (µ 4 -Se) (8a) and (µ-EtS)(µ-p-MeC 6 H 4 SO 2 )Fe 2 (CO) 6 (11a) have been confirmed by X-ray diffraction analyses.