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Manufacturing industrial transfer is an important approach topromoting the optimisation and upgrading of industry, as well as leads tothe spatial response of environmental pollution. In this paper, weapplied the gravity centre model to measure the changes in pollutantdischarge patterns from 2005 to 2015 in the Pan-Yangtze River Delta, andthen investigated the drivers of pollutant discharge patterns changeswith an improved econometric model which integrated the push-pull theoryand STIRPAT random regression model. The results revealed great changesin pollutant discharge patterns due to manufacturing industrial transfer,with the pollution gravity centre and total discharge transferring fromeast to west. We also found indications of a delayed response between themovement of industry and a corresponding reduction in pollutantemissions. The modelling results suggested that differences in regionaleconomy, technological innovation, industrial upgrading, andenvironmental regulation influenced observed changes in pollutantdischarge patterns. Specifically, regional economic conditions and morestringent environmental regulations can push pollution-intensive industryout of developed areas into developing areas. Meanwhile improvedinnovation milieu and industrial optimization provided resistance forpollution-intensive industries to stay in developed areas as well asencouraging movement into developing areas.

On the basis of total temperature increase, normal dehydration, and maturity, the odor compositions of surface and internal piles in a well-run sewage sludge compost plant were analyzed using gas chromatography–mass spectrometry with a liquid nitrogen cooling system and a portable odor detector. Approximately 80 types of substances were detected, including 2 volatile inorganic compounds, 4 sulfur organic compounds, 16 benzenes, 27 alkanes, 15 alkenes, and 19 halogenated compounds. Most pollutants were mainly produced in the mesophilic and pre-thermophilic periods. The sulfur volatile organic compounds contributed significantly to odor and should be controlled primarily. Treatment strategies should be based on the properties of sulfur organic compounds. Hydrogen sulfide, methyl mercaptan, dimethyl disulfide, dimethyl sulfide, ammonia, and carbon disulfide were selected as core indicators. Ammonia, hydrogen sulfide, carbon disulfide, dimethyl disulfide, methyl mercaptan, dimethylbenzene, phenylpropane, and isopentane were designated as concentration indicators. Benzene, m-xylene, p-xylene, dimethylbenzene, dichloromethane, toluene, chlorobenzene, trichloromethane, carbon tetrachloride, and ethylbenzene were selected as health indicators. According to the principle of odor pollution indicator selection, dimethyl disulfide was selected as an odor pollution indicator of sewage sludge composting. Monitoring dimethyl disulfide provides a highly scientific method for modeling and evaluating odor pollution from sewage sludge composting facilities. Implications: Composting is one of the most important methods for sewage sludge treatment and improving the low organic matter content of many agricultural soils. However, odors are inevitably produced during the composting process. Understanding the production and emission patterns of odors is important for odor control and treatment. Core indicators, concentration indicators, and health indicators provide an index system to odor evaluation. An odor pollution indicator provides theoretical support for further modelling and evaluating odor pollution from sewage sludge composting facilities.

Nonylphenol can be present in sewage sludge, and this can limit the use of the sewage sludge to amend soil. Composting is one of the most efficient and economical methods of making sewage sludge stable and harmless. The nonylphenol degradation rates during composting with added bulking agents and with aeration applied were studied. Three organic bulking agents (sawdust, corn stalk, and mushroom residue) were added to sewage sludge, and the effects of the bulking agents used and the amount added on nonylphenol degradation were determined. The highest apparent nonylphenol degradation rate (71.6 %) was found for sewage sludge containing 20 % mushroom residue. The lowest apparent nonylphenol degradation rate (22.5 %) was found for sewage sludge containing 20 % sawdust. The temperature of the composting pile of sewage sludge containing 20 % sawdust became too high for nonylphenol to be efficiently degraded, and the apparent nonylphenol degradation rate was lower than was found for sewage sludge containing 10 % sawdust. Increasing the ventilating time from 5 to 15 min increased the apparent nonylphenol degradation rate from 19.7 to 41.6 %. Using appropriate aerobic conditions facilitates the degradation of nonylphenol in sewage sludge, decreasing the risks posed by sewage sludge applied to land. Adding too much of a bulking agent can decrease the amount of the nonylphenol degraded. Increasing the ventilating time and the amount of air supplied can increase the amount of nonylphenol degraded even if doing so causes the composting pile temperature to remain low.

Tungsten–copper (W–Cu) composites containing 10 wt.% Cu (W–10Cu) were prepared by pressing and sintering a type of ultrafine composite powder. Constituent phases, grain size and orientation relationship between W and Cu grains were characterized and investigated. The results show that W–10Cu composites are composed of W and Cu elementary substance and orientation relationship between W and Cu grains is defined as 1 ¯ 1 ¯ 4 Cu / / 0 1 ¯ 1 W and (131)Cu//(200)W. The existence of the orientation relationship depends largely on the two factors. First, the grain sizes of both W and Cu were in the nanoscale range. Secondly, the interplanar spacing between both phases can match well owing to the residual stress of the W/Cu interface. Consequently, the obtained composites exhibited high density and excellent thermal conductivity.

A magnetic Fe 3 O 4 @ silica–xanthan gum composite was easily fabricated as a hybrid adsorbent for the removal and recovery of aqueous Pb 2+ heavy metal. The natural polymer xanthan gum (XG) was fixed on the surface of the magnetic Fe 3 O 4 microspheres through a sol–gel process. The condensation of XG molecule provided active sites for the selective adsorption of Pb 2+ ions from the aqueous solution, and because the composite is magnetically switchable, the process of solid–liquid separation was convenient. Scanning electronic microscopy, transmission electron microscopy, X-ray diffraction, Fourier transform infrared spectrometry, thermogravimetry, and BET surface area determination were utilized for the characterization of the composites. The factors affecting Pb 2+ adsorption in a batch mode were studied including the contact time (30–150 min), the pH of the media (2–10), the adsorbent dosage (0.01–0.2 g/20 mL), and the temperature (303–320 K). The Pb 2+ adsorption followed pseudo-second-order kinetics, and the maximum Pb 2+ sorption capacity was 21.32 mg g −1 at 293 K, pH = 6, according to the Langmuir isotherm. The thermodynamic parameters, including the equilibrium constant ( K 0 = 9.848), the standard free energy change (Δ G 0 = −5.774 kJ mol −1 ), the standard enthalpy change (Δ H 0 = 6.133 kJ mol −1 ), and the standard entropy change (Δ S 0 = 39.21 J mol −1 K −1 ) were discussed. The targeted Pb 2+ could be recovered efficiently using 0.05 mol L −1 HCl. Finally, the Fe 3 O 4 @ silica–XG composites were attmepted for removal of Pb 2+ from battery industry wastewater.

After a kind of volcanic tephra (VT) mineral from Changbai Mountains, Jilin, China, was entrapped into Ca-alginate (CA) beads, dried VT/CA composites were formed by microwave-assisted drying system. The acquired composites were studied for adsorptive removal of phosphate from aqueous solution. The effects of composite dosage (25–250 g/L), initial solution pH (1–10), and initial phosphate concentration (5–50 mg P/L) on phosphate removal were evaluated in a batch mode of operation. Adsorption thermodynamics (changes in the Gibbs free energy, enthalpy, and entropy) and kinetics (adsorption rate constants) have been studied. The results showed that phosphate removal capacity of ca. 0.10 mg P/g composites was achieved for the treatment of micro-polluted wastewater (15 mg P/L) with the dosage of 150 g/L under a shaking rate of 200 rpm. The phosphate removal efficiency was over 90% at aqueous solution pH of 1 to 6. Possible release of elemental ions from VT/CA composites into aqueous solution was analyzed. The mechanism of phosphate removal by the VT/CA composites was discussed and the VT/CA composites were used for phosphate removal from micro-polluted wastewater in rural area in China. Overall, the microwave-assisted dried VT/CA composites had characteristics of being convenient for processing and long-term storage, environmentally friendly, and simple manipulation at small-scale for treatment of micro-polluted wastewater.