The effect of annual additions of composted sewage sludge (CS) and thermally dried sewage sludge (TS) at 80 t ha-1 on soil chemical properties was investigated for three years in a field experiment under semiarid cond...The effect of annual additions of composted sewage sludge (CS) and thermally dried sewage sludge (TS) at 80 t ha-1 on soil chemical properties was investigated for three years in a field experiment under semiarid conditions. Humic acids (HAs) isolated by conventional procedures from CS, TS, and unamended (SO) and sludge amended soils were analysed for elemental (C, H, N, S and O) and acidic functional groups (carboxylic and phenolic) and by ultraviolet-visible, Fourier transform infrared and fluorescence spectroscopies. With respect to CS, TS had similar pH and total P and K contents, larger dry matter, total organic C, total N and C/N ratio and smaller ash content and electrical conductivity. Amendment with both CS and TS induced a number of modifications in soil properties, including an increase of pH, electrical conductivity, total organic C, total N, and available P. The CS-HA had greater O, total acidity, carboxyl, and phenolic OH group contents and smaller C and H contents than TS-HA. The CS-HA and TS-HA had larger N and S contents, smaller C, O and acidic functional group contents, and lower aromatic polycondensation and humification degrees than SO-HA. Amended soil-HAs showed C, H, N and S contents larger than SO-HA, suggesting that sludge HAs were partially incorporated into soil HAs. These effects were more evident with increasing number of sludge applications.展开更多
Based on a functional group composite strategy,the first Ag-containing phosphate-tellurite nonlinear optical(NLO)crystal,Ag(Te_(2)O_(3))(PO_(4)),was synthesized via a subcritical hydrothermal method.This crystal cryst...Based on a functional group composite strategy,the first Ag-containing phosphate-tellurite nonlinear optical(NLO)crystal,Ag(Te_(2)O_(3))(PO_(4)),was synthesized via a subcritical hydrothermal method.This crystal crystallizes in the noncentrosymmetric space group Pmn2_(1),featuring a unique zigzag two-dimensional[(Te_(2)O_(3))(PO_(4))]_(∞)layer.It possesses the strongest powder second-harmonic generation(SHG)response among all reported phosphate-tellurite compounds,reaching 2.1×KH_(2)PO_(4),along with a moderate birefringence of 0.045@546 nm.Theoretical calculations indicate that the TeO_(4)group with stereochemically active lone-pair electrons,together with AgO_(7)polyhedra and PO_(4)group,synergistically contributes to its optical properties.This functional group composite strategy not only facilitates the integration of phosphate and tellurite units with Ag+cations,but also offers a versatile route for designing NLO materials across diverse inorganic systems.展开更多
文摘The effect of annual additions of composted sewage sludge (CS) and thermally dried sewage sludge (TS) at 80 t ha-1 on soil chemical properties was investigated for three years in a field experiment under semiarid conditions. Humic acids (HAs) isolated by conventional procedures from CS, TS, and unamended (SO) and sludge amended soils were analysed for elemental (C, H, N, S and O) and acidic functional groups (carboxylic and phenolic) and by ultraviolet-visible, Fourier transform infrared and fluorescence spectroscopies. With respect to CS, TS had similar pH and total P and K contents, larger dry matter, total organic C, total N and C/N ratio and smaller ash content and electrical conductivity. Amendment with both CS and TS induced a number of modifications in soil properties, including an increase of pH, electrical conductivity, total organic C, total N, and available P. The CS-HA had greater O, total acidity, carboxyl, and phenolic OH group contents and smaller C and H contents than TS-HA. The CS-HA and TS-HA had larger N and S contents, smaller C, O and acidic functional group contents, and lower aromatic polycondensation and humification degrees than SO-HA. Amended soil-HAs showed C, H, N and S contents larger than SO-HA, suggesting that sludge HAs were partially incorporated into soil HAs. These effects were more evident with increasing number of sludge applications.
基金support by the National Natural Science Foundation of China(22375147,52332001,22305174)the National Key Research and Development Plan of the Ministry of Science and Technology(2023YFF0718900)the Natural Science Foundation of Tianjin City(22JCYBJC01380).
文摘Based on a functional group composite strategy,the first Ag-containing phosphate-tellurite nonlinear optical(NLO)crystal,Ag(Te_(2)O_(3))(PO_(4)),was synthesized via a subcritical hydrothermal method.This crystal crystallizes in the noncentrosymmetric space group Pmn2_(1),featuring a unique zigzag two-dimensional[(Te_(2)O_(3))(PO_(4))]_(∞)layer.It possesses the strongest powder second-harmonic generation(SHG)response among all reported phosphate-tellurite compounds,reaching 2.1×KH_(2)PO_(4),along with a moderate birefringence of 0.045@546 nm.Theoretical calculations indicate that the TeO_(4)group with stereochemically active lone-pair electrons,together with AgO_(7)polyhedra and PO_(4)group,synergistically contributes to its optical properties.This functional group composite strategy not only facilitates the integration of phosphate and tellurite units with Ag+cations,but also offers a versatile route for designing NLO materials across diverse inorganic systems.
