During the presummer rainy season (April–June), southern China often experiences frequent occurrences of extreme rainfall, leading to severe flooding and inundations. To expedite the efforts in improving the quantitative precipitation forecast (QPF) of the presummer rainy season rainfall, the China Meteorological Administration (CMA) initiated a nationally coordinated research project, namely, the Southern China Monsoon Rainfall Experiment (SCMREX) that was endorsed by the World Meteorological Organization (WMO) as a research and development project (RDP) of the World Weather Research Programme (WWRP). The SCMREX RDP (2013–18) consists of four major components: field campaign, database management, studies on physical mechanisms of heavy rainfall events, and convection-permitting numerical experiments including impact of data assimilation, evaluation/improvement of model physics, and ensemble prediction. The pilot field campaigns were carried out from early May to mid-June of 2013–15. This paper: i) describes the scientific objectives, pilot field campaigns, and data sharing of SCMREX; ii) provides an overview of heavy rainfall events during the SCMREX-2014 intensive observing period; and iii) presents examples of preliminary research results and explains future research opportunities.

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Phosphorus-doped copper catalysts supported on spherical activated carbon (SAC) were prepared using an incipient wetness impregnation technique. The catalysts were characterized by low-temperature N 2 adsorption/desorption, X-ray diffraction (XRD), transmission electron microscopy (TEM), temperature programmed reduction (TPR), X-ray photoelectron spectroscopy (XPS), inductively coupled plasma (ICP), N 2 O pulse titration method and thermogravimetric (TG) technologies. The results indicate that the phosphorus-doped Cu-based catalysts exhibit both high activity and good stability. The amount of phosphorus dopant has a significant effect on the catalytic activity of acetylene hydrochlorination and the optimal molar ratio of Cu/P is 2.5. The phosphorus doping facilitates the dispersion of copper species, enhances the interaction between metal and support, and restrains the growth of copper species during acetylene hydrochlorination. These results suggest that this high-activity, good-stability and low-cost catalyst has a great potential in industrial applications. 3 becoming urgent. It is known that Cu-based catalysts have been intensively investigated due to its higher activity for vapor-phase hydrogenation reaction. 16 Similarly, Cu-based catalysts as an alternative can also have good activity in acetylene hydrochlorination. Zhou, 17 for example, studied the copper chlorides NPs loaded on the nitrogen-doped carbon nanotubes (N-CNTs) for acetylene hydrochlorination and concluded that the Cu-NCNT catalyst (2.4% N) offers promoted reactivity for sustainable hydrochlorination. But, it still remains unclear what role the copper species play in the acetylene hydrochlorination reaction and in the deactivation mechanism of Cu-based catalysts, thus it is needed to be further studied.As we all know, dopants of non-metal elements like nitrogen, boron and phosphorus on carbon material can improve the performance of the catalysts for the oxygen reduction reaction. 18-21 Peng and co-workers 22, 23 prepared P-doped graphitic layers and carbon nanotubes to show high ORR performance and they found that phosphorus dopant can change the electronical structure in the network of graphitic layers so as to improve the electrocatalytic activity of catalysts. Cheng 24 found that the ORR activity can be improved owing to the formation of more structural defects after inducing phosphorus. Yang 25 reported that phosphorus doping on the standard Fe-N/C ORR catalyst exhibited a much enhanced ORR performance and the phosphorus doping process might not alter the nature of active sites but lead to the increase of ORR active site density and better dispersion of them on the catalyst surface. However, whether the P-dopant can improve the activity and the stability of 5 of Cu/P. The carbon-supported cupric pyrophosphate catalyst was also prepared using an incipient wetness impregnation technique. The pretreated carbon (5.0 g) was added to a solution of Cu 2 P 2 O 7 (A.R.) (5 mL) and maintained at 80 ºC for 12 h. The catalysts were dried at 120 °C ...

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Chlorocuprate(i) ionic liquids can be well-stabilized, low-cost, efficient and green non-mercury catalysts for hydrochlorination of acetylene.

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The design of catalyst particles bearing excellent catalytic activity and suitable surface wettability is the key to successful application of Pickering interfacial catalysis. In this study, the epoxidation of 1-hexene and cyclohexene with aqueous hydrogen peroxide over hollow TS-1 (HTS-1) zeolite was studied as a probe reaction to investigate the influence of catalyst surface wettability on catalytic activity. Hydrophobized HTS-1 particles were fabricated via a postsynthesis desilication treatment with tetrapropylammonium hydroxide and a postsynthesis silylation treatment with hexamethyldisiloxane (HMDSO). The successful preparation of HTS-1 particles was verified by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy, and Fourier-transform infrared spectroscopy. X-ray diffraction patterns and ultraviolet-visible spectra confirmed that the hydrophobic modification had no effect on the zeolite structure of HTS-1 particles. Stable Pickering emulsions of aqueous hydrogen peroxide in either 1-hexene or cyclohexene could be prepared using HTS-1 particles as emulsifiers and confirmed by cryo-SEM images. The catalytic behavior in the obtained Pickering emulsions revealed a parabolic distribution of turnover frequency values with respect to the hydrophobization degrees with 0.2-HMDSO/HTS-1 particles possessing the maximum values of 20.6 h for 1-hexene epoxidation and 8.1 h for cyclohexene epoxidation. In addition, these 0.2-HMDSO/HTS-1 particles showed good reusability for more than five cycles.