[Effects of Four Amendments on Fertility and Labile Organic Carbon Fractions of Acid Purple Soil].

The aim of this study was to explore the effects of four amendments on soil fertility and labile carbon fraction characteristics of acid purple soil, so as to provide scientific basis for nutrient management and carbon storage stability in purple soil. Field experiments were carried out, and six treatments were set up:no fertilization (CK), only chemical fertilizer (F), lime + chemical fertilizer (SF), organic fertilizer + chemical fertilizer (OM), biochar + chemical fertilizer (BF), and vinasse biomass ash + chemical fertilizer (JZ). The contents of soil organic matter, pH, available nutrients, soil integrated fertility index (IFI), dissolved organic carbon (DOC), microbial biomass carbon (MBC), particulate organic carbon (POC), their effective rates, and soil carbon pool management index (CPMI) under different treatments were studied to clarify their relationships. The results showed that:① the application of amendments significantly increased soil pH and the contents of organic matter, alkali-hydrolyzed nitrogen, available phosphorus, and available potassium (P<0.05). The OM and JZ treatments had the most significant increase in soil comprehensive fertility index (P<0.05), with increases of 1.96 and 0.77 and 170.43% and 66.96%, respectively. ② Compared with those in the control treatment, the contents of POC, MBC, and DOC in JZ and OM increased by 110.30% and 84.81%, 61.08% and 46.56%, and 195.87% and 141.67%, respectively. The application of amendments significantly increased the soil carbon pool index (CPI) and CMPI (P<0.05), in which the OM treatment showed the most significant increase, with soil CPI and CMPI values increasing by 107.34% and 90.75% compared with those of the control, respectively. ③ Soil organic carbon and its labile fractions were positively correlated with IFI (P<0.05), and redundancy analysis showed that there were significant differences among different treatments. The interpretation rates of soil IFI, pH, and available potassium to organic carbon and its components reached significant levels, and the order of interpretation rates was IFI(74.6%)>pH (11.7%)>AK(6.5%). The application of vinasse biomass ash and organic fertilizer to acid purple soil had the most significant effect on improving soil fertility and soil quality and was conducive to promoting the accumulation and activation of soil carbon fractions.

Acid Promoted Tetrafunctionalization of Terminal Alkynes: Geminal Diazidation and Dibromination.

The synthesis of complex alkanes by the tetrafunctionalization of alkynes is limited and challenging. Herein, an unprecedented efficient geminal diazidation and dibromination of terminal alkynes is developed, which provides novel access to structurally diverse organic azides. The approach has exclusive chemo- and regioselectivity and features mild reaction conditions, good tolerance of various functional groups, and more crucially, no metal involved in the reaction, thereby benefiting the late-stage decoration of medicinal molecules. A mechanistic study showed that the current geminal diazidation and dibromination proceeds via a radical pathway.

[Effects of Four Amendments on Cadmium Bioavailability and Enzyme Activity in Purple Soil].

In this study, the effects of four types of amendments on effective Cd and Cd content in different parts of prickly ash soil and soil enzyme activity were studied, which provided scientific basis for acidification improvement of purple soil and heavy metal pollution control. A field experiment was conducted. Six treatments were set up:no fertilizer (CK), only chemical fertilizer (F), lime + chemical fertilizer (SF), organic fertilizer + chemical fertilizer (OM), biochar + chemical fertilizer (BF), and vinasse biomass ash + chemical fertilizer (JZ). Soil pH; available Cd (DTPA-Cd); Cd content in branches, leaves, shells, and seeds of Zanthoxylum; as well as the activities of catalase (S-CAT), acid phosphatase (S-ACP), and urease (S-UE) in different treatments were studied, and their relationships were clarified. The results showed following:① The two treatments of vinasse biomass ash + chemical fertilizer and lime + chemical fertilizer significantly increased soil pH (P < 0.05) to 3.39 and 2.25 units higher than that in the control, respectively. Compared with that in the control treatment, the content of available Cd in soil under vinasse biomass ash + chemical fertilizer and lime + chemical fertilizer treatment decreased by 28.91 % and 20.90 %, respectively. ② The contents of Cd in leaves, shells, and seeds of Zanthoxylum were decreased by 31.33 %, 30.24 %, and 34.01 %, respectively. The Cd enrichment ability of different parts of Zanthoxylum was different, with the specific performances being leaves > branches > seeds > shells. Compared with that of the control, the enrichment coefficient of each part of Zanthoxylum treated with vinasse biomass ash + chemical fertilizer decreased significantly(P < 0.05)by 27.54 %-40.0 %. ③ The changes in catalase and urease activities in soil treated with amendments were similar. Compared with those in the control group, the above two enzyme activities were significantly increased by 191.26 % and 199.50 %, respectively, whereas the acid phosphatase activities were decreased by 16.45 %. Correlation analysis showed that soil available Cd content was significantly negatively correlated with soil pH value(P < 0.01), S-CAT and S-UE enzyme activities were significantly positively correlated with soil pH(P < 0.01), and the soil available Cd content was significantly negatively correlated (P < 0.01); the S-ACP enzyme showed the complete opposite trends. The application of lime and vinasse biomass ash to acidic purple soil had the most significant effect on neutralizing soil acidity. It was an effective measure to improve acidic purple soil and prevent heavy metal pollution by reducing the effective Cd content in soil and improving the soil environment while inhibiting the absorption and transfer of Cd in various parts of Zanthoxylum.

Kinetically controlled synthesis of low-strain disordered micro-nano high voltage spinel cathodes with exposed {111} facets.

High-voltage LiNi0.5Mn1.5O4 (LNMO) is one of the most promising cathode candidates for rechargeable lithium-ion batteries (LIBs) but suffers from deteriorated cycling stability due to severe interfacial side reactions and manganese dissolution. Herein, a micro-nano porous spherical LNMO cathode was designed for high-performance LIBs. The disordered structure and the preferred exposure of the {111} facets can be controlled by the release of lattice oxygen in the high-temperature calcination process. The unique configuration of this material could enhance the structural stability and play a crucial role in inhibiting manganese dissolution, promoting the rapid transport of Li+, and reducing the volume strain during the charge/discharge process. The designed cathode exhibits a remarkable discharge capacity of 136.7 mA h g-1 at 0.5C, corresponding to an energy density of up to 636.4 W h kg-1, unprecedented cycling stability (capacity retention of 90.6% after 500 cycles) and superior rate capability (78.9% of initial capacity at 10C). The structurally controllable preparation strategy demonstrated in this work provides new insights into the structural design of cathode materials for LIBs.

Developing an abnormal high-Na-content P2-type layered oxide cathode with near-zero-strain for high-performance sodium-ion batteries.

Layered transition metal oxides (NaxTMO2) possess attractive features such as large specific capacity, high ionic conductivity, and a scalable synthesis process, making them a promising cathode candidate for sodium-ion batteries (SIBs). However, NaxTMO2 suffer from multiple phase transitions and Na+/vacancy ordering upon Na+ insertion/extraction, which is detrimental to their electrochemical performance. Herein, we developed a novel cathode material that exhibits an abnormal P2-type structure at a stoichiometric content of Na up to 1. The cathode material delivers a reversible capacity of 108 mA h g-1 at 0.2C and 97 mA h g-1 at 2C, retaining a capacity retention of 76.15% after 200 cycles within 2.0-4.3 V. In situ diffraction studies demonstrated that this material exhibits an absolute solid-solution reaction with a low volume change of 0.8% during cycling. This near-zero-strain characteristic enables a highly stabilized crystal structure for Na+ storage, contributing to a significant improvement in battery performance. Overall, this work presents a simple yet effective approach to realizing high Na content in P2-type layered oxides, offering new opportunities for high-performance SIB cathode materials.