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Urban ecosystem resilience is a key concern in the strategy of ecological protection and high-quality development in the Yellow River Basin. This paper uses the principle of range maximization to construct an ecosystem resilience index measurement model from the four dimensions of energy, water resources, environment, and economy and society. The spatio-temporal evolution ecosystem resilience of 99 cities in nine provinces of the Yellow River Basin from 2005 to 2019 was analyzed. The spatial econometric model was used to explore the impact of technological innovation, opening to the outside world and industrial structure on the level of ecosystem resilience, so as to provide guidance for improving the level of ecosystem resilience in the Yellow River Basin. The results are concluded as follows: The level of ecosystem resilience in the Yellow River Basin generally increased first, then decreased, and then increased again. The resilience contribution of the environmental subsystem and the economic and social subsystem is relatively large, while the resilience contribution of the water resource subsystem is relatively small. How to improve the resilience level of the water resource subsystem should be considered as a key issue. Scientific and technological innovation, opening to the outside world and industrial structure had obvious spatial impacts on the resilience of the ecosystem in the Yellow River Basin.

Water pollution has been acknowledged as an issue of concern due to recalcitrant pollutants like textile dyes. Therefore, the eco-friendly synthesis of nano-particles (NPs) through green chemistry approach from sources and materials of organic origin has not only enhanced the properties of substance at nanoscale but has also reduced the toxicological impacts on human health and the environment. In this study a successful attempt was made to synthesize TiO2 NPs by Mangifera indica leaves extract as organic source. The structural morphology was determined by carrying out FTIR, SEM, EDX and XRD techniques. The removal of Methylene Blue (MB) dye was assessed by the application of the photocatalysis technique. The experiments were designed using the RSM (CCD) approach for selected parameters such as pH, TiO2 NPs, Dye concentration and Time. The maximal dye removal efficiency of 98% was achieved at optimum conditions of 4.7 pH, 0.04g of nano photocatalyst in 250ml of dye solution having 8ppm concentration, allowed to react for 45 min. The regression coefficient value of 79.37% was determined by ANOVA for MB dye. The results clearly indicate that the application of green nanoparticles for the removal of MB dye is a feasible option to overcome with the ever-increasing issue of water pollution and environmental degradation.

A series of flow-cell experiments were performed to investigate the performance of cosmetic rhamnolipid surfactant flooding on the relationship between source zone mass removal and mass flux reduction for pool-dominated DNAPL TCE source zones in heterogeneous porous media. The results were also compared to those of water-flood control experiments to assess the surfactant enhanced flushing efficacy. The flooding experiments were performed for silica sand and natural calcareous soil representing two different degrees of physical heterogeneity. The result from the flow-cell experiments showed that higher than 97% of TCE mass was removed during rhamnolipid flooding for both porous media scenarios. Although, rhamnolipid flooding experiment results showed successful remediation performance, DNAPL TCE dissolution and rhamnolipid-enhanced dissolution in heterogeneous porous media system exhibited multi-step mass-flux reduction/mass-removal behavior due to the presence of less hydraulically-accessible pool-dominated TCE source zone. However, mass removal and mass-flux reduction relationships for rhamnolipid flushing cases exhibited more ideal removal behavior, indicating the more efficient remediation performance compared to water flooding alone. For all cases, the later stage of mass removal was controlled by the more poorly-accessible mass associated with pool-dominated source zones. The results of this study revealed the impact of non-uniformity of the flow-field and effect of enhanced-solubilization agent on mass removal and mass-flux reduction behavior for DNAPL source zones in saturated porous media

The wastes are in many forms consist of organic materials like human, medical, food, plastics, construction waste etc. many researchers are focused on the waste management to gives more importance to the environment. The bio degradable waste was used in this research with naturals fibers. The need for hybrid composites has increased in a variety of industrial applications. A unique and useful substance is created when two or more distinct components join in this kind of composite. Because of its exceptional characteristics, research is being done on the integration of particles bio waste and fiber into polymers. The like a strong weight-to-strength ratio, immunity to rust and temperature changes, and several custom qualities. This research focuses on the property description of Calotropis Gigantea and Bio waste ashes in form of epoxy matrix and in concrete as retrofitting composite. Calotropis Gigantea and Bio waste ashes are in composite form. field emission scanning electron microscope (FESEM) The characterisation is used to make sure that the polymer's structural shape and particle dispersion are correct. The mechanical, dynamic mechanical, thermal wear and concrete strength qualities are assessed. When particles are added, the qualities improve. By raising the weight of particle at certain percentage to the matrix and concrete mixture is for to increase the mechanical properties like tension, elongation, impact. To analyze the tribological behaviour, wear analysis is carried out. The results revealed that, the laminates reinforced with Calotropis Gigantea and Bio waste ashes show maximum strength. This is correlated with the increased interaction between the fiber-matrix, waste ash and homogeneous dispersion particle and also having greater strength compare to conventional concrete. The FESEM micrographs for tensile fracture surface also provided structural morphology. The findings will provide a vivid understanding for the use of composites in various structural retrofitting applications.