Application of biochar-based fertilizer (BF), produced by combining biochar with chemical fertilizer, is known to be an effective way to increase plant growth and soil organic carbon (SOC) stock, but ...its impact on soil respiration (RS) components and associated mechanisms in subtropical plantations remain unclear. The objectives of this 12-month field study were (1) to examine the effects of the application of a BF versus a chemical fertilizer (CF) on seasonal variations in soil heterotrophic (RH) and autotrophic (RA) respiration in a subtropical plantation of Moso bamboo (Phyllostachys edulis), and (2) to investigate relationships between soil RH and RA and soil environmental factors in different fertilizer treatments. Four treatments were tested: control (no fertilizer applied), BF application, CF application, and a 50: 50 mixture of BF and CF (BCF). Irrespective of the treatment, both RS and RH exhibited strong seasonal patterns. However, adding CF in the soil significantly increased the soil RH whereas BF decreased it (P < 0.05). Both CF and BF significantly (P < 0.05) increased soil RA. The RS, RH and RA were all exponentially related (P < 0.05) to soil temperature regardless of the treatment, and the Q10 value of RH was greater than that of RA (P < 0.05). Applying CF increased the Q10 for RH (P < 0.05), yet the application of BF did not affect it. Although the RS, RH and RA were not related to the soil moisture content in all treatments, both RS and RH were correlated (P < 0.05) with soil water soluble organic C and microbial biomass C concentrations, and also with soil invertase and β-glucosidase activities. In conclusion, compared with the conventional chemical fertilizer use, the novel management practice of biochar-based fertilizer application offers advantages, such as reducing soil C emissions and increasing SOC content, which has the implication of mitigating soil greenhouse gas emissions in subtropical Moso bamboo plantations.
•Biochar-based fertilizer decreased while chemical fertilizer increased soil RH•Both biochar-based and chemical fertilizers increased soil RA•Chemical fertilizer but not biochar-based fertilizer increased the Q10 of soil RH•Biochar-based fertilizer enhanced soil fertility but reduced enzyme activity•Biochar-based fertilizer has a greater potential to reduce soil C emissions
The crystallographic structure of the products had great influence on the catalytic performance in formaldehyde oxidation. Thereinto, the catalytic activity of the cryptomelane-type MnO
2 was higher ...than other crystalline manganese oxides below 120
°C.
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► A facile hydrothermal route was used to fabricate flower-like MnO
2 nanospheres as assembled by layered MnO
2 nanosheets. ► Control over the morphology, structure and crystalline phase of manganese oxide nanomaterials can be achieved by tuning reaction conditions. ► Birnessite-type, cryptomelane-type and ramsdellite MnO
2 nanostructures were successfully fabricated. ► On the basis of experimental results, the formation mechanism of the products was investigated and discussed. ► The crystallographic structure had great influence on the catalytic performance in formaldehyde oxidation.
Flower-like manganese oxide nanospheres as assembled by layered MnO
2 sheets have been successfully fabricated via a facile route using a hydrothermal treatment at 120
°C for 12
h. XRD, FE-SEM, TEM and BET were used to investigate the crystalline structure, morphology, specific surface area, and porosity of the products. The products have a BET surface area of ca. 94.6
m
2/g. Effects of preparation conditions including hydrothermal temperature, reaction time, pH value and kinds of anion were investigated on the morphology, structure and crystalline phase. It was found that control over the morphology and structure of product can be achieved by tuning reaction conditions. On the basis of experimental results, the formation mechanism of the products was investigated and discussed. The manganese oxide nanomaterials showed high catalytic activities for oxidative decomposition of formaldehyde. The crystallographic structure of the products had great influence on the catalytic performance in formaldehyde oxidation. Thereinto, the catalytic activity of the cryptomelane-type MnO
2 was higher than other crystalline manganese oxides below 120
°C.
CaBi2Nb2O9 (CBN) with the Aurivillius phase has a high Curie temperature (TC) and remarkable fatigue resistance, which has great potential for application as high-temperature sensors. However, due to ...its low piezoelectric properties, its practical application remains a great challenge. In this paper, Ca1-xCexBi2Nb2O9 ceramics were prepared by the direct reaction sintering (DRS) and conventional preparation (CP) methods, respectively. The experimental results indicate that Ce doping can increase the piezoelectric coefficient d33 of CBN ceramics by about two times. Among them, the grain size of the samples prepared by the DRS method is finer and more uniform, and the d33 value of DRS samples is about 3.6–9.4 % higher than that of CP samples. The DRS sample Ca0·97Ce0·03Bi2Nb2O9 has a d33 value of 18.9 pC/N, a TC of 948 °C, and a resistivity of 1.1 × 105 Ω cm at 600 °C. This study shows that DRS method is an effective densification method, which can prepare CBN-based ceramics with excellent comprehensive properties, and provides an innovative preparation route to explore CBN-based ceramics with excellent piezoelectric properties.
Changes in soil aggregation with biochar amendment have been investigated extensively, but how biochar affects the chemical composition of organic carbon (C) and biological binding agents in ...aggregates and their linkage with soil aggregate stability remains unclear. Soil samples were collected in a rice paddy treated with 0 (C0, control), 10 t ha−1 (C10), 20 t ha−1 (C20) and 40 t ha−1 (C40) biochar for twenty months. The amount and chemical composition of soil organic C (SOC), microbial abundances and glomalin-related soil protein (GRSP) were determined in bulk soil and four fractions: large macroaggregates (>2000 μm), small macroaggregates (250–2000 μm), microaggregates (53–250 μm), and silt + clay (<53 μm). Our results showed that the proportion of >250 μm water-stable aggregates and mean weight diameter were gradually increased with increasing biochar addition rate. The concentrations of SOC, readily oxidizable C and microbial biomass C increased most in the small macroaggregates, followed by microaggregates under biochar amendment. Increasing biochar addition rate gradually decreased the relative contents of alkyl C, O-alkyl C and carbonyl C, but increased those of aromatic C across the aggregates, resulting in a higher aromaticity and hydrophobicity of SOC with respect to the control. The abundances of bacteria, fungi and archaea and the content of GRSP were significantly enhanced in the large and small macroaggregates under the C40 treatment. The proportion of >250 μm aggregates was significantly correlated with the contents of soil organic C fractions, GRSP and microbial abundance. Structural equation modeling further revealed that changes in SOC hydrophobicity and GRSP content under biochar amendment had significant and direct effects on the soil aggregate size distribution. In summary, our findings suggest that biochar amendment in rice paddy could improve soil aggregation through altering the chemical composition of soil organic C and the abundance of biological binding agents.
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•The chemical nature of soil organic C in aggregates was determined in rice paddy soil with and without biochar amendment.•Biochar increased aromaticity and hydrophobicity of soil organic C in aggregates.•Biochar at 40 t ha−1 increased microbial abundances and GRSP in macroaggregates.•Hydrophobicity of SOC and GRSP had direct effects on the soil aggregate stability.
Abstract Iso-butene (iso-C 4 H 8 ) is an important raw material in chemical industry, whereas its efficient separation remains challenging due to similar molecular properties of C 4 olefins. The ...ideal adsorbent should possess simultaneous high uptakes for 1,3-butadiene (C 4 H 6 ) and n-butene (n-C 4 H 8 ) counterparts, endowing high efficiency for iso-C 4 H 8 separation in adsorption columns. Herein, a sulfate-pillared adsorbent, SOFOUR-DPDS-Ni (DPDS = 4,4′-dipyridyldisulfide), is reported for the efficient iso-C 4 H 8 separation from binary and ternary C 4 olefin mixtures. The rigidity in pore sizes and shapes of SOFOUR-DPDS-Ni exerts the molecular sieving of iso-C 4 H 8 , while exhibiting high C 4 H 6 and n-C 4 H 8 uptakes. The benchmark Henry’s selectivity for C 4 H 6 /iso-C 4 H 8 (2321.8) and n-C 4 H 8 /iso-C 4 H 8 (233.5) outperforms most reported adsorbents. Computational simulations reveal the strong interactions for C 4 H 6 and n-C 4 H 8 . Furthermore, dynamic breakthrough experiments demonstrate the direct production of high-purity iso-C 4 H 8 (>99.9%) from C 4 H 6 /iso-C 4 H 8 (50/50, v / v ), n-C 4 H 8 /iso-C 4 H 8 (50/50, v / v ), and C 4 H 6 /n-C 4 H 8 /iso-C 4 H 8 (50/15/35, v / v / v ) gas-mixtures.
Conventional analysis of heavy metal ions in water requires highly skilled staff and sophisticated equipment. These limitations make conventional approaches difficult to perform analysis on-site ...without delay. Herein, we report a facile colorimetric sensing system developed for acute toxicity assessment of heavy metal ions. A bioactive enzyme, β-galactosidase, was used as sensing agent rather than bacteria or other higher organisms to improve selectivity and response time. The developed bioassay is capable of assessing the toxicity of heavy metal ions such as Hg(II), Cd(II), Pb(II), and Cu(II). The effects of enzyme concentration on the assessing performances (i.e., sensitivity and response time) of bioassay were explored and illustrated. Generally, low enzyme concentration facilitates sensitivity enhancement, achieving a 50% inhibiting concentration (IC50) of 0.76 μM (=152 ppb) Hg(II), and high enzyme concentration ensures quick response, enabling a response time down to 9 min. Moreover, the enzyme and substrate were respectively encapsulated by hydrogel to further simplify the assay procedure and enhance the stability of the enzyme. The hydrogel-encapsulated enzyme worked well even when heated up to 60 °C and retained ca. 90% activity after storage for 5 months. Moreover, the developed toxicity-assessing system is feasible for assessing toxicity of actual water samples. This assay approach is low cost and time effective and has no potential ethic issues. In addition, this work paves the way for the development of toxicity assessment kits for on-site analysis based on functional bioactive molecules.
A class of nitrogenous porous carbon materials (OAMPCs) has been successfully fabricated for the enrichment of ultra-trace hexachlorocyclohexane (HCH) in real water samples. The obtained optimal ...nitrogenous porous carbon material (OAMPC-700) has a porous curled graphene-like carbon-nanosheets morphology, large surface area (506.4 m2 g−1) and large pore volume (2.49 cm3 g−1), as well as abundant oxygen- and nitrogen-containing functional groups. Based on such unique structural characteristics, OAMPC-700 exhibits rapid uptake kinetics (99.2% HCH within just 1 min) and a superior maximum capacity (751.6 mg g−1). After six cycles of tests, OAMPC-700 still maintains a 94.27% removal percentage towards HCH, which is only 5.53% lower than that of original OAMPC-700, demonstrating the outstanding reusability. OAMPC-700 was applied to pre-enrich ultra-trace HCH from water sample with a portable enrichment equipment, demonstrating fast speed, high efficiency, and low energy consumption. Corresponding standard curves were obtained between enrichment (Cen) and initial (Cin) concentrations of HCH with a correlation coefficient (R2 =0.9901), significantly pushing down the detection limit of common analytical instruments. The enrichment mechanism for OAMPC-700 towards HCH mainly includes the synergism of hydrophobicity and hydrogen-bonding. This work may open a new avenue to the fabrication of unique carbon materials for the adsorption, enrichment, separation, and ultimate detection of ultra-trace organic pollutants.
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•Nitrogenous porous carbon material (OAMPC-700) was fabricated.•Enrichment of ultra-trace organochlorine pesticides (HCH).•99.2% HCH removed by OAMPC-700 within 1 min•Organochlorine pesticides maximum capacity is 751.6 mg g−1.•Pushing down the detection limit of analytical instruments.
Jianwei Xiaoyan Granule (JWXYG) is the traditional Chinese medicine preparation in Jiangyin Hospital Affiliated to Nanjing University of Chinese Medicine, which has been widely used in clinical ...treatment of chronic atrophic gastritis (CAG). However, the material basis and potential mechanism of JWXYG in the treatment of CAG are not clear.
To explore the material basis and potential mechanism of JWXYG in the treatment of CAG.
In this study, the components of JWXYG were analyzed by HPLC-Q-TOF-MS/MS. Then, the CAG model in rats established by a composite modeling method and MC cell model induced by MNNG were used to explore the improvement effect of JWXYG on CAG. Finally, the potential mechanism of JWXYG in the treatment of CAG was preliminarily predicted based on network pharmacology and validated experimentally.
Thirty-one components of JWXYG were analyzed through HPLC-Q-TOF-MS/MS, such as albiflorin, paeoniflorin, lobetyolin firstly. Research results in vivo showed that the gastric mucosa became thinner, intestinal metaplasia appeared, the number of glands was reduced, the serum levels of PG I and PG II increased and the contents of G17 and IL-6 reduced in CAG model rats. After 4 weeks of JWXYG (2.70 g/kg) administration, these conditions were significantly improved. In addition, cell viability, migration, and invasion of MNNG-induced MC cells was inhibited by JWXYG treatment (800 μg/mL). Furthermore, the results of network pharmacology indicated that HIF-1 and VEGF signaling pathways might play important roles in the therapeutic process. Then the results of Western blot, immunohistochemistry and immunofluorescence confirmed that with JWXYG treatment, the increased expression of HIF-1α, VEGF and VEGFR2 in gastric issue of CAG rats were restrained. Eventually, potential components of JWXYG in the treatment of CAG were predicted through molecular docking to elucidate the material basis.
JWXYG could inhibit angiogenesis by regulating HIF-1α-VEGF pathway to exert therapeutic effects on CAG. Our study explored the potential mechanisms and material basis of JWXYG in the treatment of CAG and provides experimental data for the clinical rational application of JWXYG.
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► Porous manganese oxide K-OMS-2 nanomaterials were successfully synthesized by a simple soft chemistry route. ► K-OMS-2 nanoparticles show rather higher catalytic activity for ...complete oxidation of formaldehyde than K-OMS-2 nanorods. ► More than 64% of HCHO could be oxidized into CO
2 at 100
°C over the K-OMS-2 nanoparticles.
Porous manganese oxide K-OMS-2 nanomaterials were successfully synthesized by a simple low-temperature method. Data collected from characterization methods affirmed the cryptomelane-type manganese oxide octahedral molecular sieve (OMS-2). With increase of reaction temperature, the nanoparticle morphology of K-OMS-2 with an average diameter of ca. 40
nm evolved into nanorod morphology with a diameter of ca. 40
nm and lengths of 50–500
nm. Results of catalytic tests revealed that K-OMS-2 nanoparticles show rather higher catalytic activity for complete oxidation of formaldehyde than K-OMS-2 nanorods. This simple, inexpensive, and environmentally friendly method may have the potential of being used in scaled-up of K-OMS-2 materials.
Intensive forest management practices, such as fertilization, understory removal and deep tilling, play an important role in improving plant growth in forests through altering nutrient availability ...and soil structure. However, how such management affects soil microbial community diversity and functions related to nutrient cycling remains largely unknown. In this study, we investigated the responses of soil bacterial community composition and enzyme activities involved in C, N and P cycling to long-term intensive management, and identified the critical determinants that regulated them across a chronosequence of Moso bamboo forests (0, 10, 15, 20 and 25 years of intensive management) in subtropical China. Our results demonstrated that intensive management decreased soil pH and aggregation and increased mineral nutrient contents. Illumina MiSeq sequencing showed that significant (P < 0.05) shifts of the soil bacterial community composition occurred after 15 years of management. Diversity indices (phylogenetic diversity, OTU richness and Chao1) generally decreased after 15 years of management. Soil pH, NO3−-N, and available P and K contents were key factors shaping the bacterial community composition. Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt) predicted lower functional diversity of soil bacterial microbiomes as related to the cycling of amino acids and carbohydrates after 15 and 20 years. The activities of β-glucosidase and phosphatase decreased markedly after 15 years of intensive management, but rebounded after 25 years. Structural equation modeling provided evidence that the response of soil enzyme activities to forest management was mediated by changes in bacterial composition and diversity. Our study suggests that intensive forest management decreases microbial diversity indices and changed community composition, which could have direct consequences for soil functioning.
•The effects of intensive forest management on soil microbial community were investigated.•Prolonged intensive management decreased bacterial diversity indices and metabolic function.•Changes in enzyme activity were tightly linked to bacterial community and function.•The observed decreases in microbial diversity may have direct consequences for soil functioning.
