Spatio-Temporal Distributions and Environmental Safety Threshold of Cropland Fertilization of Jiangsu

Abstract: Correlations and non-linear regression analyses were used to determine the optimal rate of fertilization that would maximize production of grain while minimizing effects on the environment in Jiangsu Province, China. Correlation coefficients between the amounts of cereal grain produced and rates of fertilization were 0.880, 0.606, and 0.212 for the period

Spatio-Temporal Distributions and Environmental Safety Threshold of Cropland Fertilization of Jiangsu

Abstract: Correlations and non-linear regression analyses were used to determine the optimal rate of fertilization that would maximize production of grain while minimizing effects on the environment in Jiangsu Province, China. Correlation coefficients between the amounts of cereal grain produced and rates of fertilization were 0.880, 0.606, and 0.212 for the period

Spatio-Temporal Distributions and Environmental Safety Threshold of Cropland Fertilization of Jiangsu

Abstract: Correlations and non-linear regression analyses were used to determine the optimal rate of fertilization that would maximize production of grain while minimizing effects on the environment in Jiangsu Province, China. Correlation coefficients between the amounts of cereal grain produced and rates of fertilization were 0.880, 0.606, and 0.212 for the period

Linear-dendritic block copolymers as a green scale inhibitor for calcium carbonate in cooling water systems

Water-soluble monomer APEG-PG-(OH)n were produced and the Structure of APEG-PG-(OH)5 were identified by 1H-NMR. APEG-PG-(OH)n were copolymerized with maleic anhydride (MA) to synthesize no phosphate and nitrogen free calcium carbonate inhibitor MA/APEG-PG-(OH)n. The structure and thermal property of MA/APEG-PG-(OH)5 were characterized and measured by 1H-NMR, GPC and TGA. The observation shows that the dosage and n value of MA/APEG-PG-(OH)n plays an important role on CaCO3 inhibition. MA/APEG-PG-(OH)5 displays superior ability to inhibit the precipitation of calcium carbonate, with approximately 97% inhibition at a level of 8 mg/L. The effect on formation of CaCO3 was investigated with combination of SEM and XRD analysis

Regional Differences and Key Influencing Factors of Fertilizer Integrated Efficiency in China

Overuse and low efficiency of chemical fertilizers have caused severe non-point source pollution in China. The investigation of regional difference and the key influencing factors of fertilization intensities (FI) and efficiency can provide references for decision-makers to establish efficient policies for fertilizer use. Using simple models of fertilizer allocation efficiency (FAE) and fertilizer integrated efficiency (FIE), it was found that the east of China excessively used fertilizers, and both the middle and west showed both excessive and insufficient fertilizer use. The average values of the FIE in the east, middle and west of China were 0.69, 0.68 and 0.64, respectively, all of which were at low efficiency. The inter-provincial differences of FIE throughout the country ranged from 0.47 in Shannxi to 0.94 in Shanghai. The population aging rate (PAR), effective irrigation rate (EIR), natural disasters affected rate (DAR) and disaster damaged rate (DDR) are considered the key factors influencing the FIE, based on the new concept of cumulative weight (CW). PAR and EIR are the positive factors, while DAR and DDR are negative. The average FIE is now 0.67 in China, which implies that the increase of chemical fertilizer use efficiency or the reduction of chemical fertilizer amount has a potential of approximate 33%, with the current grain yield and other inputs unchanged. The increase of fertilizer use efficiency should be conducted under local conditions. Optimized intensification of grain production should be given more attention in the east, and implementing disaster prevention and reduction technologies and water-saving irrigation technologies are the preference in the middle and west of China

Role of Materials Chemistry on Transparent Conductivity of Amorphous Nb-Doped SnO2 Thin Films Prepared by Remote Plasma Deposition

In this study, remote plasma sputtering deposition of niobium-doped SnO2 transparent conductive oxides on glass substrates was carried out at ambient temperature with no post-deposition annealing. The microstructure, optical, electrical, and surface morphology of the thin films were characterized using a combination of advanced techniques, such as X-ray diffraction (XRD), UV-Vis spectrophotometer, Hall-effect measurements, as well as field emission scanning electron microscope (FESEM), high-resolution transmission electron microscopy, and high-resolution X-ray photoelectron spectroscopy. It was determined that the oxygen defects of the films have a substantial impact on their transparent conductivity. The crystalline films, which were crystallized by annealing at 450 °C, had higher resistivities due to a decreased concentration of oxygen vacancies, which restricted conduction. In comparison, the amorphous films exhibited remarkable conductivity. The best amorphous films (Nb:SnO2) exhibited a resistivity of less than 4.6 × 10−3 Ω·cm, with a 3 × 1020 cm−3 carrier concentration and a 4.4 cm2/(V·S) of Hall mobility. X-ray amorphous Nb:SnO2 films can be used to make conductive and transparent protective layers that can be used to shield semiconducting photoelectrodes used in solar water splitting. These layers can also be used with more conductive TCO films (ITO or AZO) when needed