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Sebacate (SB) molecules were incorporated into Ca Al layered double hydroxides (CaAL-LDH) using a hydrothermal method. The resulting products underwent characterization through X-ray diffraction, infrared spectroscopy, and scanning electron microscopy. To investigate the release kinetics and thermodynamics of the corrosion inhibitor, total organic carbon analysis (TOC) was employed. A comparison was made with CaAl-LDH prepared without corrosion inhibitors, in which nitrates were the primary anions within the layered clay structure. An assessment of anion exchange between nitrates and chlorides was conducted using total nitrogen analysis (TN). The SB anion comprised approximately 49.2% of the total dried powder synthesized, with a maximum release efficiency of around 86.7% fitting a Langmuir model. For the evaluation of the corrosion inhibition effect on steel surfaces, electrochemical impedance spectroscopy, potentiodynamic polarization, and scanning vibrating electrode technique were employed. The corrosion inhibition impact was ascribed to the liberation of SB anions from the CaAl-LDH pigments, accompanied by alkalinization stemming from partial particle dissolution. Additionally, the incorporation of organic molecules notably enhanced the stability of pigments in aqueous solutions compared to similar ones hosting nitrates. These findings suggested that CaAl-LDH pigments have potential as nanocontainers for organic inhibitors, showing promising prospects in the field of corrosion research. [Display omitted] • Synthesis of CaAl-LDHs particles with sebacate intercalated. • Sebacate anionic exchange with chlorides is efficient at 86.7%. • Organic molecule intercalation gives improved stability in water. • Steel corrosion protection is provided by chloride trapping and inhibitor release. [ABSTRACT FROM AUTHOR]

Polyhydroxyalkanoates (PHA) are bioplastics which are well known as intracellular energy storage compounds and are produced in a large number of prokaryotic species. These bio-based inclusions are biodegradable, biocompatible and environmental friendly. Industrial production of, short chain and medium chain length PHA, involves the use of microorganisms and their enzymes. Priestia megaterium previously known as Bacillus megaterium is a well-recognized bacterium for producing short chain length PHA. This study focuses to characterize this bacterium for the production of medium chain length PHA, and a novel blend of both types of monomers having enhanced properties and versatile applications. Statistical analyses and simulations were used to demonstrate that cell dry weight can be derived as a function of OD 600 and PHA content. Optimization of growth conditions resulted in the maximum PHA production as: 0. 05 g. g-x. H−1, where the rate of PHA production was 0.28 g L−1. H−1 and PHA concentration was 4.94 g. L−1. This study also demonstrated FTIR to be a semi quantitative tool for PHA production. Moreover, conversion of scl-PHA to mcl-PHA with reference to time intermissions using GC-FID are shown. • Priestia megaterium showed metabolic shift in PHA production by converting PHB into mcl-PHA using two different media. • Statistical analysis optimized the C/N ratio, and concentrations of growth constituents to enhance the mcl-PHA production. • Electron microscopy evaluated the size, structure and shape of PHA granules with respect to time intervals. [ABSTRACT FROM AUTHOR]

Highlights • Adding fertilizers had no adverse effects on the compost fermentation process. • Organic-inorganic aerobic co-composting increased compost nutrients contents. • Adding biochar contributed to the decomposition of stubborn carbonaceous matter. • Biochar improved nitrogen transformation and reduced nitrogen loss. • The 10–15% addition dose of biochar by weight is optimum in this study. Abstract In this article, the changes in carbon, nitrogen components, and humic substances during organic-inorganic aerobic co-composting, with adding biochar as an additive or not, were studied. Results showed that adding a certain amount of inorganic fertilizers had no adverse effects on the compost fermentation process. Biochar enhanced the temperature, pH, oxygen content in the compost piles and ultimately hastened the fermentation process. Biochar contributed to the decomposition of hemicellulose, cellulose, lignin and promoted compost humification. Adding biochar increased the contents of acid hydrolysis nitrogen, amino acid nitrogen, amino sugar nitrogen, unidentified organic nitrogen and decreased the content of ammonia organic nitrogen thus improved nitrogen transformation and reduced nitrogen loss. The addition of biochar increased the nutrients contents in mature composts. The amendment of 10–15% biochar by weight as an additive would be optimum for the co-composting of organic-inorganic materials. These results contributed to produce value-added composting fertilizers. [ABSTRACT FROM AUTHOR]

Decomposing vertebrate cadavers release large, localized inputs of nutrients. These temporally limited resource patches affect nutrient cycling and soil organisms. The impact of decomposing cadavers on soil chemistry is relevant to soil biology, as a natural disturbance, and forensic science, to estimate the postmortem interval. However, cadaver impacts on soils are rarely studied, making it difficult to identify common patterns. We investigated the effects of decomposing pig cadavers (Sus scrofa domesticus) on soil chemistry (pH, ammonium, nitrate, nitrogen, phosphorous, potassium and carbon) over a one-year period in a spruce-dominant forest. Four treatments were applied, each with five replicates: two treatments including pig cadavers (placed on the ground and hung one metre above ground) and two controls (bare soil and bags filled with soil placed on the ground i.e. "fake pig" treatment). In the first two months (15-59 days after the start of the experiment), cadavers caused significant increases of ammonium, nitrogen, phosphorous and potassium (p<0.05) whereas nitrate significantly increased towards the end of the study (263-367 days; p<0.05). Soil pH increased significantly at first and then decreased significantly at the end of the experiment. After one year, some markers returned to basal levels (i.e. not significantly different from control plots), whereas others were still significantly different. Based on these response patterns and in comparison with previous studies, we define three categories of chemical markers that may have the potential to date the time since death: early peak markers (EPM), late peak markers (LPM) and late decrease markers (LDM). The marker categories will enhance our understanding of soil processes and can be highly useful when changes in soil chemistry are related to changes in the composition of soil organism communities. For actual casework further studies and more data are necessary to refine the marker categories along a more precise timeline and to develop a method that can be used in court. [ABSTRACT FROM AUTHOR]

Precipitation behavior and tensile properties have been investigated for 15Cr-15Mn-4Ni austenitic steels containing 0.2 wt% carbon and/or 0.2 wt% nitrogen. During aging at 600–1000 °C, precipitates such as σ, M 23 C 6 , and Cr 2 N were formed and time-temperature-precipitation diagrams were constructed. The type, size, and density of precipitates depended on the carbon and nitrogen contents. The nitrogen addition suppressed carbide formation while the effect of carbon addition on nitride precipitation was comparatively small. The evolution of tensile properties after aging is explained by the changes in solid solution strengthening and deformation modes caused by the precipitation. The precipitation of M 23 C 6 slightly decreased yield strength and elongation while it increased ultimate tensile strength. On the other hand, the precipitation of Cr 2 N hardly affected tensile properties due to its low volume fraction. [ABSTRACT FROM AUTHOR]

Herein, the multiporous MnO/N-doped carbon (MnO/NC) composite based on the abundant and inexpensive electrolytic manganese dioxide were fabricated through a facile microwave-assisted carbonthermal reduction, combined with a subsequent in-situ polymerization of polydopamine onto MnO along with thermal treatment. As an anode material, it retains a reversible capacity of 770.5 mAh g −1 at 300 mA g −1 and high Coulombic efficiency of 99% over 500 cycles, superior than those values of the pure multiporous MnO alone. The impressive performance is attributed to the splendid structure stability contributed by well-connected three-dimensional porous configuration and the enhanced reaction kinetics as well as electrical conductivity incurred by N-doped carbon layer with multiple type nitrogen. [ABSTRACT FROM AUTHOR]

Soil samples from the Forensic Anthropology Research Facility (FARF) at Texas State University, San Marcos, TX, were analyzed for multiple soil characteristics from cadaver decomposition islands to a depth of 5centimeters (cm) from 63 human decomposition sites, as well as depths up to 15cm in a subset of 11 of the cadaver decomposition islands plus control soils. Postmortem interval (PMI) of the cadaver decomposition islands ranged from 6 to 1752 days. Some soil chemistry, including nitrate-N (NO3-N), ammonium-N (NH4-N), and dissolved inorganic carbon (DIC), peaked at early PMI values and their concentrations at 0-5cm returned to near control values over time likely due to translocation down the soil profile. Other soil chemistry, including dissolved organic carbon (DOC), dissolved organic nitrogen (DON), orthophosphate-P (PO4-P), sodium (Na+), and potassium (K+), remained higher than the control soil up to a PMI of 1752days postmortem. The body mass index (BMI) of the cadaver appeared to have some effect on the cadaver decomposition island chemistry. To estimate PMI using soil chemistry, backward, stepwise multiple regression analysis was used with PMI as the dependent variable and soil chemistry, body mass index (BMI) and physical soil characteristics such as saturated hydraulic conductivity as independent variables. Measures of soil parameters derived from predator and microbial mediated decomposition of human remains shows promise in estimating PMI to within 365days for a period up to nearly five years. This persistent change in soil chemistry extends the ability to estimate PMI beyond the traditionally utilized methods of entomology and taphonomy in support of medical-legal investigations, humanitarian recovery efforts, and criminal and civil cases. [ABSTRACT FROM AUTHOR]

This study cultivated denitrifying granular sludge in three UASB reactors by the semi-starvation fluctuation C/N ratio strategy (reactor 1 (R1): constant C/N ratio; R2: regular fluctuation C/N ratio; and R3: semi-starvation fluctuation C/N ratio (SSF)). Microbial aggregates appeared in R1, R2 and R3 on days 28, 14 and 6, respectively. Compared with the results in R1 and R2, the guanosine tetraphosphate (ppGpp) concentration was highest, the acyl homoserine lactones (AHLs) concentration quickly reached a certain threshold, and more protein (PN) of extracellular polymeric substances (EPS) secretion resulted in the rapid formation of denitrifying granular sludge in R3. The SSF strategy enhances microbial diversity, and denitrifying granular sludge has a better nitrogen removal performance. The result demonstrates that ppGpp, AHLs, EPS and the denitrifying sludge granulation process are associated. A mechanism for denitrifying sludge granulation with SSF strategy was proposed from the aspect of quorum sensing (QS). [ABSTRACT FROM AUTHOR]

We report an eco-friendly strategy for fabrication of nitrogen-doped carbon nanodots (N-CDs) and demonstrate their applications for multicolor cell imaging, patterning, and biosensing. N-CDs have been synthesized using wool as raw material via pyrolysis and microwave treatment, providing a green way for the production of N-CDs without the use of toxic/expensive solvents and starting materials. The prepared N-CDs exhibit exceptional advantages including high fluorescent quantum yield (22.5%), excellent biocompatibility, low toxicity, and satisfactory chemical stability. Depending on these superior properties, the N-CDs have been applied in multicolor bioimaging, patterning, and biosensing. Imaging of living cells has been observed with high resolution using N-CDs as a probe, which validates their use in imaging applications and their multicolor property in the living cell system. Additionally, the obtained N-CDs have been used as fluorescent inks for drawing luminescent patterns, showing favorable application in anti-counterfeit and optoelectronic dimensions. Most strikingly, the as-prepared N-CDs could visualize Fe 3+ fluctuations in living cells with negligible autofluorescence based on their high sensitivity and selectivity detection for Fe 3+ ions with a linear range of 0.1–10 μM and a detection limit of 10 nM. [ABSTRACT FROM AUTHOR]

In the presence of ( R )-SEGPHOS-PdCl 2 catalyst, 5- endo -hydroaminocyclization of various 2-( tert -butyl)- N -(2-ethynylphenyl)anilines proceeds enantioselectively to afford optically active N–C axially chiral N -(2- tert -butylphenyl)indole derivatives in good yields. The enantioselectivity depends strongly on the bulkiness of ortho -substituents and the electron density on the arylethynyl group, and it is explained by the dynamic axial chirality generated by the twisting of the aryl substituent. [ABSTRACT FROM AUTHOR]

Axially chiral N -arylindoles and realated compounds were stereoselectively synthesized using the following three protocols; 1) diastereoselective nucleophilic aromatic substitution, 2) desymmetrization via a stereoselective Cr(CO) 3 migration reaction, and, 3) catalytic enantioselective synthesis via asymmetric ring-closing metathesis. Arene chromium tricarbonyls were utilized as key building blocks, and all of these methods induced extremely high stereoselectivities. Moreover, Cr(CO) 3 fragments were easily removed via air oxidation condition to afford Cr-free N -arylindoles with axially chiral N–C bonds. [ABSTRACT FROM AUTHOR]

The development of efficient and durable catalyst for oxygen reduction reaction (ORR) is critical for the practical application of proton exchange membrane fuel cell (PEMFC). A novel imidazole based ionic liquid is synthesized in this study and used subsequently for the preparation of a N and S co-doped metal-free catalyst with three dimensional ordered microstructure. The catalyst prepared at 1100 °C showed improved ORR catalytic performance and stability compared to commercial Pt/C catalyst. We demonstrate that the high graphitic N content and high degree of graphitization of the synthesized catalyst is responsible for its superb ORR activity. Our results suggest that the N and S co-doped metal-free catalyst reported here is a promising alternative to traditional ORR catalyst based on noble metal. Furthermore, the current study also demonstrate that importance of morphology engineering in the development of high performance ORR catalyst. [ABSTRACT FROM AUTHOR]

Fine particulate matter (PM 2.5) significantly impacts global air quality and human health due to its smaller particle size and larger specific surface area. Nitrogen and carbon aerosols, as the main components of PM 2.5 , play key roles in air pollution. This study identified the sources and seasonal variation of nitrogen and carbon aerosols in PM 2.5 in typical cities of Zhejiang. The annual average PM 2.5 concentrations of Hangzhou (HZ), Ningbo (NB), and Huzhou (HUZ) were 39.8 ± 19.1 μg m−‍3, 40.0 ± 21.5 μg m−3, and 50.1 ± 22.6 μg m−3, respectively, which exceeded the Chinese air quality limit of 35.0 μg m−3. The results showed that the concentrations of nitrogen aerosols (NO 3 − and NH 4 +) in water-soluble inorganic ions were higher at 9.6 ± 4.6 μg m−3, 9.0 ± 4.5 μg m−3 and 11.5 ± 5.4 μg m−3 in HZ, NB and HUZ, respectively, especially in winter, accounting for over 60% of the total. The annual average δ15N values of PM 2.5 were 6.2 ± 1.9‰, 6.4 ± 2.2‰ and 6.7 ± 1.9‰ in HZ, NB and HZ, respectively; the δ15N values in winter were relatively low. A Bayesian isotopic mixing model was employed to analyse the sources of nitrogen aerosols in winter; the results showed that nitrogen concentration was mainly affected by NH 3 and NO X emitted by motor vehicle exhaust, coal combustion, biomass combustion, biogenic soil emissions, animal wastes and ocean evaporation (NB). In addition, the carbon component analysis of PM 2.5 showed that the annual average mass concentration of TC accounted for 18.7%, 16.4% and 20.1% of PM 2.5 in HZ, HUZ and NB, respectively. The same isotope model was used to analyse the sources of carbon aerosols; the results showed that carbon aerosols were mainly affected by the sources of motor vehicle exhaust, coal combustion, biomass combustion and dust. In the PM 2.5 in Zhejiang, the most contributory sources of nitrogenous aerosols and carbon aerosols were motor vehicle exhaust sources. [Display omitted] • The fractionation coefficients for nitrogen aerosol conversions are different in Hangzhou, Ningbo, and Huzhou. • The NO X and NH 3 sources of aerosol NO 3 − and NH 4 + in Hangzhou, Ningbo, and Huzhou were identified. • The stable carbon and nitrogen isotope values of dust sources in Hangzhou, Ningbo and Huzhou are significantly different. • The main sources of carbon aerosol are motor vehicle exhaust in Hangzhou, Ningbo and Huzhou. [ABSTRACT FROM AUTHOR]

A new isolated Schizochytrium sp. LU310 from the mangrove forest of Wenzhou, China, was found as a high producing microalga of docosahexaenoic acid (DHA). In this study, the significant improvements for DHA fermentation by the batch mode in the baffled flasks (i.e. higher oxygen supply) were achieved. By applied the nitrogen-feeding strategy in 1000 mL baffled flasks, the biomass, DHA concentration and DHA productivity were increased by 110.4%, 117.9% and 110.4%, respectively. Moreover, DHA concentration of 21.06 g/L was obtained by feeding 15 g/L of glucose intermittently, which was an increase of 41.25% over that of the batch mode. Finally, an innovative strategy was carried out by intermittent feeding carbon and simultaneously feeding nitrogen. The maximum DHA concentration and DHA productivity in the fed-batch cultivation reached to 24.74 g/L and 241.5 mg/L/h, respectively. [ABSTRACT FROM AUTHOR]

An analytical method for 14 C in environmental water based on a wet-oxidation process was developed. The method can be used to determine the activity concentrations of organic and inorganic 14 C in environmental water, or total 14 C, including in drinking water, surface water, rainwater and seawater. The wet-oxidation of the organic component allows the conversion of organic carbon to an inorganic form, and the extraction of the inorganic 14 C can be achieved by acidification and nitrogen purging. Environmental water with a volume of 20 L can be used for the wet-oxidation and extraction, and a detection limit of about 0.02 Bq/g(C) can be achieved for water with carbon content above 15 mg(C)/L, obviously lower than the natural level of 14 C in the environment. The collected carbon is sufficient for measurement with a low level liquid scintillation counter (LSC) for typical samples. Extraction or recovery experiments for inorganic carbon and organic carbon from typical materials, including analytical reagents of organic benzoquinone, sucrose, glutamic acid, nicotinic acid, humic acid, ethane diol, et cetera ., were conducted with excellent results based on measurement on a total organic carbon analyzer and LSC. The recovery rate for inorganic carbon ranged tween 98.7%–99.0% with a mean of 98.9(±0.1)%, for organic carbon recovery ranged between 93.8% and 100.0% with a mean of 97.1(±2.6)%. Verification and an uncertainty budget of the method are also presented for a representative environmental water. The method is appropriate for 14 C analysis in environmental water, and can be applied also to the analysis of liquid effluent from nuclear facilities. [ABSTRACT FROM AUTHOR]

Codonopsis pilosula is a traditional Chinese herbal medicinal plant and contains various bioactive components, such as C. pilosula polysaccharides (CPPs) and lobetyolin (Lob). Hydrogen peroxide (H 2 O 2) and nitric oxide (NO) are gaseous molecule and have been well known for their ability to relieve some adverse influences on plant from abiotic stress. Endophytic fungus is non-pathogenic plant-associated fungus that could play a significant role in improving plant tolerance by signal molecule. In this work, we determined how inoculation of Trichoderma strain RHTA01 with C. pilosula changed the plant's growth, metabolite accumulation, and related enzyme activity. Results demonstrated that application of Trichoderma strain RHTA01 significantly improved the growth of C. pilosula. Moreover, it noticeably decreased antioxidant enzyme superoxide dismutase (SOD) and catalase (CAT) activity in C. pilosula leaves, reduced the content of H 2 O 2 and malondialdehyde (MDA), and weakened the peroxidation of cell membrane lipids, which reduced the damage of abiotic stress to C. pilosula. Research has shown that it had obvious effects on levels of nitrogen and carbon metabolic enzymes. For example, sucrose synthase (SS) and acid invertase (AI) levels in C. pilosula roots were nearly 1.43 and 1.7 times higher, respectively, than those in the control (CK) group. In addition, it was notable that the production of CPPs and Lob, the most significant secondary metabolites in C. pilosula , were influenced by Trichoderma strain RHTA01. The obtained results indicate that inoculating C. pilosula with Trichoderma stimulates the carbon and nitrogen metabolism of the plant, and helps to increase the content of CPPs and Lob in the root of the plant. [Display omitted] • Application of FG (Trichoderma) can improve the growth of C. pilosula. • With FG applied, it improved the antioxidant properties of C. pilosula. • The FG improves the content of CPPs and Lob of C. pilosula. • The possible mechanisms are explored between Trichoderma and C. pilosula. [ABSTRACT FROM AUTHOR]