In the World Cultural Heritage of Leshan Giant Buddha and the West Lake area, the statues and monuments have been affected by the colonizing organisms. In the past three years, we used next-generation sequencing technology to analyze the biofilm of 14 sites in two places. The result showed that microbiomes were different on monuments, especially in terms of microbial composition, diversity, and potential functions. More phototrophic organisms and bacteria involved in the nitrogen-sulfur cycle were found in the West Lake area (WLA), while heterotrophs were discovered in the Leshan Giant Buddha area (LGBA). The biofilms on sandstone in LGBA possessed a higher alpha diversity of bacteria and fungi community than that on limestone in WLA. Biofilms in LGBA showed higher gene expression in metabolisms, such as the metabolism of carbohydrates, lipids, xenobiotics, and terpenoids. While biofilms in WLA exhibited higher levels of genetic information processing genes, which are associated with coping with harsh environments. Combine with XRD and SEM-EDS analysis, petrographic properties were considered the main factors that affect biological colonization. Environmental conditions (temperature, humidity, and precipitation) were similar in the two regions, which are suitable for the growth of organisms. Microbiome dissimilarities (beta diversity) indicated that the microbial compositions of biofilms were associated with the geographic features of the sampling sites. The stones in the two regions have their own petrographic properties that greatly influence microbiome colonization, such as microstructure, porosity, water permeability, and minerals composition.
The problem of offshore oil leakage has wreaked havoc on the environment and people’s health. A simple and environmentally friendly impregnation method combined with marine mussel bionics was used to address this issue. Using the viscosity of polydopamine (PDA), nano- Fe3O4 and WS2 adhered to the framework of the melamine sponge (MS), and then the magnetic sponge was modified with n-octadecanethiol (OTD), and finally the superhydrophobic magnetic melamine sponge (mMS) was prepared. The modified sponge has superhydrophobicity (WCA, 156.8° ± 1.18°), high adsorbability (40~100 g°g−1), recyclability (oil adsorbability remains essentially unchanged after 25 cycles), efficient oil–water separation performance (>98%), and can quickly separate oil on the water’s surface and underwater. Furthermore, the modified sponge exhibits excellent stability and durability under harsh operating conditions such as strong sunlight, strong acid, strong alkali, and high salt, and can control the direction of the sponge’s movement by loading a magnetic field. To summarize, mMS has many potential applications as a new magnetic adsorption material for dealing with complex offshore oil spill events.
The discharge of oily wastewater and oil spills at sea are the current difficulties in water pollution control. This problem often leads to terrible disasters. Therefore, the effective realization of oil-water separation is a very challenging problem. Superhydrophobic sponge is a promising oil-absorbing material. In this article, we reported a superhydrophobic sponge with nano-Fe3O4 for oil-water separation. The addition of nano-Fe3O4 allows the sponge to be recycled under the action of magnetic force. The sponge has the advantages of low cost, simple preparation and efficient oil-water separation. This kind of sponge is very worthy of promotion for the treatment of oily wastewater and marine oil spill accidents.
With the intensification of human activities, a large amount of oil and organic solvent waste has been created, resulting in serious ecological and environmental pollution. Therefore, how to balance environmental benefits and economic benefits control a large number of organic solvent and oil pollution is an urgent problem. To solve this problem, a highly efficient oil-water separation material was designed and prepared in this paper. Graphene oxide aerogels were synthesized by the Pickering emulsion and hydrothermal method, and then hydrophobically lipophilic polydimethylsiloxane (PDMS) reduced graphene oxide aerogel composites (PDMS/GA) were obtained by modification of PDMS. The surface functional groups, hydrophobicity, thermal stability, and micromorphology of the materials were tested by various characterization methods. Their properties were tested by an oil absorption test and repeated experiments. The oil absorption performance experiments and repeated performance experiments of PDMS/GA are reported. The number of oxy-gen-containing functional groups of the modified graphene oxide (GO) decreased, and the contact angle of water was 134.4°. The adsorption capacity of n-hexane was up to 18.5 times its own weight. The material has the advantages of being lightweight, easy to recover, good hydrophobicity and lipophilicity, and has the potential for large-scale applications in the field of oil-water separation.
To explore the synergistic mechanism of polymer and surfactant in the binary combination flooding of low-permeability reservoirs, the adaptability experiment of polymer salt-resistant partially hydrolyzed polyacrylamide and nonionic surfactant was carried out in the indoor system. Experiments at different ratios are also performed. The results show that the selected poly/surface binary flooding system increases with the concentration of polymer or surfactant, the viscosity of the poly/surface binary system also increases and, at the same time, has better temperature and salt resistance. The viscosity of the binary system will decrease when the salinity increases. When the surfactant concentration CS = 0.2% and the polymer concentration CP = 0.2%, the viscosity of the system is the highest. The viscosity of the poly/table binary system at different concentrations decreases when the temperature rises: pure polymer (CP = 0.2%), poly/table binary system displacement fluid CP = 0.1% + CS = 0.2% and CP = 0.2% + CS = 0.2%; and the injection pressure first rises and then drops. The final recovery rate is 51.8%, which meets the development of most oil reservoirs.