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In this study, we demonstrate the applicability of nitrogen microwave inductively coupled atmospheric pressure mass spectrometry (MICAP-MS) for Ca, Fe, and Se quantification in human serum using isotope dilution (ID) analysis. The matrix tolerance of MICAP-MS in Na matrix was investigated, revealing that high Na levels can suppress the signal intensity. This suppression is likely due to the plasma loading and the space charge effect. Moreover, 40Ca and 44Ca isotopic fractionation was noted at elevated Na concentration. Nine certified serum samples were analyzed using both external calibration and ID analysis. Overestimation of Cr, Zn, As, and Se was found in the results of external calibration, which might result from C-induced polyatomic interference and signal enhancement, respectively. Further investigations performed with methanol showed a similar enhancement effect for Zn, As, and Se, potentially supporting this assumption. The mass concentrations determined with ID analysis show metrological compatibility with the reference values, indicating that MICAP-MS combined with ID analysis can be a promising method for precise Ca, Fe, and Se determination. Moreover, this combination reduces the influence of matrix effects, broadening the applicability of MICAP-MS for samples with complex matrixes. [ABSTRACT FROM AUTHOR]

Purpose: Diet-related diseases are advancing as the leading cause of death globally. As self-reporting of diet by patients can be associated with errors, stable isotopes of human tissues can be used to diagnose diseases, understand physiology, and detect change in diet. This study investigates the effect of type and amount of food on the nitrogen and carbon concentration (Nconc and Cconc) and isotopic composition (δ15N and δ13C) in human scalp hair and fingernails. Methods: A total of 100 residents participated in the study whereas only 74 individuals provided complete diet history. Sixty-six food items majorly available to them were also collected. The Nconc, Cconc, δ15N and δ13C values of human hair, nails and food items were determined. Results: The Nconc, Cconc, δ15N and δ13C values between plant-sourced and animal-sourced food items, as well as human hair and nail tissue were significantly different (p < 0.05). The δ15N value of human tissues was distinct between lacto-vegetarians and omnivores by 0.9‰. The δ15N and δ13C values of human tissues increased by 0.4–0.5‰ with every 5% increase in the consumption of animal protein. Conclusions: The study helps to demarcate lacto-vegetarians from omnivores, and estimate the percentage of animal protein in diet based on the dual isotope values of human tissues. It also acts as a reference to determine isotopic composition of hair tissue provided the isotope value of nail tissue is known and vice versa. [ABSTRACT FROM AUTHOR]

Large predators are essential in maintaining ecosystem functioning, and comprehending how their feeding habits change across natural and human-dominated landscapes is crucial to preserve biodiversity. In this study, the diet of Iberian wolves (Canis lupus signatus) during pup rearing season (July to September) has been studied in relation to prey abundance and putting emphasis in the analysis of the differences between zones, wolf groups and individual factors (age, sex and social status). For this, non-invasive monitoring was carried out in three zones of Spain where nine different wolf breeding groups were detected (Galicia, n = 4; Zamora, n = 4 and Valladolid, n = 1). Faecal samples were collected near breeding sites for dietary and genetic analyses, registering if it was or not a scent mark to know the social status of the individuals. Prey availability was determined by camera trapping or requesting the official census of wild prey in the study areas. We found differences in wolf’s diet depending on the zone and the breeding group however, the diet did not vary depending on the age, sex and social status. In general, Iberian wolves mainly fed on wild ungulates (wild boar, roe deer and red deer), feeding on the most abundant prey, except for Baldriz group in Galicia which seems to be specialized in hunting roe deer. Domestic animals’ consumption (sheep, goat, donkey, pig) was not high, but it occurred specially in agriculture and livestock areas (Ferreras in Zamora and Valladolid) where wild prey were less available. Significance statement: In this study, we shed light on the vital role of Iberian wolves in the ecosystem by investigating the dietary preferences during pup rearing season across different landscapes. Our research revealed differences in wolf diets based on geographic location and breeding groups, emphasizing their adaptability. We found that age, sex, and social status did not significantly influence their dietary preferences. Iberian wolves predominantly target wild ungulates, except for a specialized group in Galicia. Our study introduces a novel approach as it is the first to analyse wolf diet based on individual factors and using nitrogen analysis. Additionally, the study highlights previously overlooked dietary patterns of the Iberian wolf subspecies, despite its critical role in the ecosystem as a top predator. Furthermore, we emphasize the necessity of conserving wild ungulate populations to reduce livestock attacks by ensuring a stable supply of wild prey, promoting coexistence between humans and wolves. [ABSTRACT FROM AUTHOR]

The so-called man-eating wolves of Turku, a pack of three wolves, reportedly killed 22 children in South-Western Finland in 1880–1881. Enormous efforts were carried out to eradicate them. In January 1882 the last remaining wolf was killed. Since then, there has been considerable debate regarding the validity and extent of the man-eating behaviour. This study aims to clarify whether man-eating behaviour can be observed from the remains of these wolves. One of the wolves was mounted in 1882 and is on display at St. Olaf's school in Turku, enabling us to collect hair keratin samples. Additionally, hair keratin was collected from two other suspected man-eaters. We analysed carbon (δ13C) and nitrogen (δ15N) stable isotope values to study the wolf's diet during the last months of its life. Samples from seven temporally concurrent wolves were used to construct reference values. Our analyses indicated that δ15N values of suspected man-eaters were relatively low compared to the reference sample. We could not detect clear trends in isotope ratios associated with potential man-eating behavior. We believe that this lack of distinctive patterns can be explained by the relatively minor role that man-eating played in their overall diet. [ABSTRACT FROM AUTHOR]

In this study, the production of two-stage metal-free catalysts from pistachio shells, which are abundant in Turkey and the world, is designed. The first stage of the study includes activated carbon(AC) production, and the second stage includes the production of heteroatom-doped catalysts as a result of hydrothermal heating of the obtained activated carbon with nitric acid. These metal-free catalysts obtained were used for the production of hydrogen (H2) from sodium borohydride (NaBH4) in methanol. In H2 production experiments, the NaBH4 concentration effect, temperature effect and catalyst amount effect and catalyst reusability parameters were investigated. HGR values obtained from the methanolysis using metal-free catalysts treated by the nitric acid/water ratio: 1:2, 1:3, 1:4, 1:5 are 8041, 8955, 10600 and 8333 ml min−1 g−1, respectively. The activation energy (Ea) of the production of H2 from NaBH4(NaBH4–H2–P) in methanol by the metal-free catalyst was 18.19 kJ mol−1. Fourier-transform infrared spectroscopy (FTIR), X-ray powder diffraction (XRD), CHNS elemental analysis, scanning electron microscopy (SEM), and nitrogen adsorption analyses were performed for the characterization of the metal-free catalysts obtained. In addition, the mechanism of the obtained metal-free catalysts on the NaBH4–H2–P in methanol is discussed. [ABSTRACT FROM AUTHOR]

Nanostructured scaffolds based on cellulose with advanced performances and personalized morphologies for bone tissue engineering are under technological development. 3D-printing and supercritical carbon dioxide (scCO2) technologies are innovative processing strategies that, when combined, allow the precise fabrication of highly porous aerogel scaffolds. Novel sterile cellulose-in-cellulose aerogels decorated with superparamagnetic iron oxide nanoparticles (SPIONs) are synthesized in this work by an integrated technological platform based on 3D-printing and scCO2. Methylcellulose (MC) and bacterial nanocellulose (BC) are two versatile cellulosic polysaccharides with remarkable physicochemical and biological performances, whereas SPIONs are commonly used to functionalize biomaterials aimed at tissue engineering. Aerogels with hierarchical porosity and high structural resolution were obtained according to nitrogen adsorption–desorption analysis, confocal, scanning and transmission microscopies (SEM and TEM). The magnetic properties of SPIONs-doped aerogels confirmed the correct functionalization of the nanostructures. Finally, NIH/3T3 fibroblast cell viability, hemocompatibility with human blood and safety tests (in ovo with HET-CAM and in vivo with Artemia salina) indicate the biocompatibility of the cellulose-in-cellulose aerogels. [ABSTRACT FROM AUTHOR]

The Lower Laguna Madre of Texas (LLM) is a subtropical, hypersaline lagoon dominated by lush seagrass beds and characterized by a historically low freshwater inflow (FWI) regime. From 1998 to 2012, a net 8.8% seagrass decrease occurred in the LLM, primarily Syringodium filiforme and Thalassia testudinum, despite the concomitant expansion of Halodule wrightii. In the middle region of the LLM affected by a major FWI source, the Arroyo Colorado, the decrease was > 20%. We proposed that Thalassia and Syringodium decrease was largely due to high FWI pulses and N loading from an increasingly modified LLM watershed. Salinity modeling studies showed that FWI pulses lowered salinities for months in this region potentially associated with non-point source nutrient (viz. ungauged) inputs. At a site near the Arroyo Colorado, Thalassia biomass and shoot density were lower 319.3 g/m2 and 567 shoots/m2, respectively versus 1296 g/m2 and 3382 shoots/m2 for the most productive LLM site. Targeted sampling in four subwatersheds adjacent to the LLM demonstrated high dissolved N loadings (nitrate and organic nitrogen) to the lagoon. Nitrogen isotope analysis of LLM seagrass further indicated that nitrogen was likely from inland wastewater runoff from the Arroyo Colorado. We concluded that freshwater pulses to the lagoon produce hyposaline conditions and high nutrient loading, stressing seagrasses and resulting in diminished resilience and reduced distribution of Thalassia and Syringodium. With climate change, coastal population growth, and enhanced watershed drainage, episodes of hyposalinity, and enriched nutrient runoff are likely to increase in frequency and duration, altering seagrass resilience and diversity in the LLM. [ABSTRACT FROM AUTHOR]

Adsorption-based atmospheric water harvesting has emerged as a compelling solution in response to growing global water demand. In this context, Metal–organic frameworks (MOFs) have garnered considerable interest due to their unique structure and intrinsic porosity. Here, MOF 801 was synthesized using two different methods: solvothermal and green room temperature synthesis. Comprehensive characterization indicated the formation of MOF-801 with high phase purity, small crystallite size, and excellent thermal stability. Nitrogen adsorption–desorption analysis revealed that green-synthesized MOF-801 possessed an 89% higher specific surface area than its solvothermal-synthesized counterpart. Both adsorbents required activation at a minimum temperature of 90 °C for optimal adsorption performance. Additionally, green-synthesized MOF-801 demonstrated superior adsorption performance compared to solvothermal-synthesized MOF-801, attributed to its small crystal size (around 66 nm), more hydrophilic functional groups, greater specific surface area (691.05 m2/g), and the possibility of having a higher quantity of defects. The maximum water adsorption capacity in green-synthesized MOF-801 was observed at 25 °C and 80% relative humidity, with a value of 41.1 g/100 g, a 12% improvement over the solvothermal-synthesized MOF-801. Remarkably, even at a 30% humidity level, green-synthesized MOF-801 displayed a considerable adsorption capacity of 31.5 g/100 g. Importantly, MOF-801 exhibited long-term effectiveness in multiple adsorption cycles without substantial efficiency decline. [ABSTRACT FROM AUTHOR]

A new pilot plant equipment with application of the ammonium fluorine technology for processing silicon-containing raw materials using the physical effects of sublimation and desublimation has been developed and manufactured. It is shown that the usage of the created device for the processing of metallurgical waste makes it possible to separate amorphous silicon dioxide in the form of a dispersed powder from slags, extract iron oxide, and obtain a collective concentrate of valuable components. The synthesized silicas have been studied by inductively coupled plasma (ICP) mass-spectrometry, scanning electron microscopy, X-ray diffraction, small angle X-ray scattering, laser correlation spectroscopy, and low-temperature nitrogen adsorption–desorption analysis. It has been shown that an increase in hexafluorosilicate concentration by 10 times during the silica synthesis led to increasing effective diameter of silica particles more than four times, and a decrease in the SiO2 yield by ~ 25%. The silica samples have amorphous structure and purity ≥ 99.97%. The specific surface area is equal to 58 m2/g for silica synthesized using copper melting slag and SBET = 10 m2/g for silica synthesized from microsilica prepared using ferrosilicon production waste. The total pore volume is 0.22 cm3/g and 0.08 cm3/g for these silica samples, respectively. There is a fraction of pores inaccessible (closed) for nitrogen molecules that can be detected with the SAXS method since there is a relation SSAXS > SBET. Thus, the use of waste from metallurgical industries allows one to implement a resource-saving technology for producing highly disperse silica with appropriate textural characteristics. [ABSTRACT FROM AUTHOR]

Marine flatfishes have a low metabolic rate and routinely encounter large fluctuations in salinity, and are therefore of interest in the study of diffusive water flux (a proxy for transcellular water permeability), oxygen consumption (ṀO2), ammonia excretion and urea-N excretion as a function of salinity and seawater [Ca2+]. These parameters were measured in two coastal marine flatfishes, Pacific sanddab and Rock sole acclimated to 31 ppt and exposed acutely (for up to 3 h), to environmentally relevant salinities of 45, 15.5, or 7.5 ppt. In both species, diffusive water flux and ammonia excretion rates increased as salinity decreased. ṀO2 and urea-N excretion rates remained relatively unchanged. Nitrogen quotient analysis indicated increased oxidation of protein at lower salinity. A second experimental series was performed on Rock sole to separate the effects of salinity from those of ambient [Ca2+]. In direct contrast to the significant increase seen at 7.5 ppt, reducing salinity from 31 ppt to 7.5 ppt while maintaining [Ca2+] at 10 mM or increasing it to 20 mM resulted in no change in diffusive water flux rate, demonstrating that reduced [Ca2+], rather than reduced salinity itself, is the primary cause for the increases in diffusive water flux. However, ammonia excretion rate increased when salinity was decreased and [Ca2+] was increased compared to 31 ppt with added [Ca2+]. Our results demonstrate that both diffusive water flux and ammonia excretion rates are a function of salinity, that neither are coupled to ṀO2, and that ambient [Ca2+] also plays a role in these rates. [ABSTRACT FROM AUTHOR]

NaBi(MoO4)2 mesoporous material was prepared by a simple solvothermal method. Co3O4 and CuO doped NaBi(MoO4)2 composites were prepared by sintering NaBi(MoO4)2 nanoparticles covered with the corresponding nitrate. The NaBi(MoO4)2 and the composites were characterized by XRD, SEM, TEM and nitrogen adsorption–desorption analysis. The results show that NaBi(MoO4)2 was mesoporous structures assembled by random aggregation of nanoparticles with an average grain size of about 31 nm. In the composite, the Co3O4 was obtained and uniformly distributed on the surfaces of NaBi(MoO4)2 nanoparticles to form heterojunctions. The sensor based on pure NaBi(MoO4)2 mesoporous material showed a response value of up to 44.8 for 100 ppm n-butanol at an optimum operating temperature of 260 °C with a fast response and recovery time. The Co3O4-doped NaBi(MoO4)2 composite exhibited superior gas-sensitive properties over the pure NaBi(MoO4)2 mesoporous material. The sensor based on 1.0 wt% Co3O4-doped NaBi(MoO4)2 showed a response value of 63 for 100 ppm n-butanol at 260 °C. [ABSTRACT FROM AUTHOR]

As environmentally friendly materials, cellulose cryogels are good choices due to their biodegradability and ease of use. However, the most crucial issue concerning cellulose cryogels is their weakness in terms of mechanical properties. In this study, two types of Polyamide-Epichlorohydrine resins, named PAE1 and PAE2, and Polyamide-Glutaraldehide-Epichlorohydrine resin (PGE) were synthesized; they were utilized to reinforce cellulose nanofiber gel (CNFG), and this was followed by the freeze-drying process. The density and porosity of the cryogels were improved and evaluated using mathematical equations. The mechanical behavior of the fabricated specimens was examined to obtain the optimized values of processing time and temperature, as well as the resin weight fraction, which yielded the improvement of compressive modulus, yield strength, and the stress at 60% strain (S60) to 2 (MPa), 50 (kPa), and 1.8 (MPa) respectively. Also, attenuated total reflection (ATR) analysis was conducted to study the effect of resins on the cross-linking of cellulose nanofibers (CNF)s; further, nitrogen adsorption–desorption analysis was performed to investigate the specific surface area and mesopore diameter distribution of cryogels using Brunauer–Emmett–Teller (BET) and Barrett-Joyner-Halenda (BJH) methods, respectively. [ABSTRACT FROM AUTHOR]

The present study deals with the effect of dyeing on different types of regenerated cellulosic fibres such as viscose, modal, and lyocell, and on different modifications of regenerated cellulosic fibres such as non-woven fibres, anionically modified viscose fibre, cationically modified viscose fibre, and hydrophobic viscose fibre. The water-soluble direct dye and reactive dye were used to colour these fibres. The dye pickup of these regenerated cellulosic fibres was studied by evaluating and comparing the extent of colour exhaustion in terms of K/S values measured by a spectrophotometer. The dye pickup behaviour of fibres was observed to be different in the case of reactive and direct dyes. Based on the experiments, the factors influencing on the dye pickup of regenerated cellulosic fibres were narrowed down to modified functionality of the fibre and properties such as, denier, surface area, and % crystallinity of the fibres. Furthermore, the dyed samples were examined using SEM, optical microscopes for morphology studies, XPS and nitrogen estimation analysis to understand the functionality changes on the fibres, and UV Vis spectrophotometry was carried out to understand dye bath exhaustion, and the FTIR spectra of fibre were done to analyse the functional group variation in cellulose before and after dyeing. It was observed that the increase in crystallinity of fibres lower down the dye pickup, and the functional modification with cationic, hydrophobic, or non-woven additives increases the dye pickup. [ABSTRACT FROM AUTHOR]

The study focused on litter processing efficiency of the sesarmid crab, Parasesarma plicatum under experimental conditions and its possible role in carbon structuring in the mangrove habitats. The feeding experiment of crab with different stages of leaves of diverse mangrove species revealed that senescent brown leaves were preferred the most, due to their lesser tannin content. The leaf consumption differed significantly with leaf state as well as mangrove species and highest was for Avicennia officinalis brown leaves. The ingestion-egestion assay of P. plicatum revealed that it assimilated an average of 65.75 ± 10.30% of mangrove litter. The experimental study also revealed that rather than already reported C/N ratio, the inhibiting factors such as tannin and lignin like substances control the palatability of leaves by the crab species. The analysis of carbon and nitrogen variants in the experimental water indicated that handling of leaves by the crab helps in leaching of nutrients to the substratum. Therefore, the findings of litter processing efficiency of this sesarmid crab from the present study highlights its significance in structuring the carbon in natural mangrove habitat. [ABSTRACT FROM AUTHOR]

The genetic architecture of nitrogen use efficiency (NUE) and its two component traits i.e. NUpE (N uptake efficiency) and NUtE (N utilization efficiency) was studied using a bi-parental RIL mapping population derived from a cross HUW468 (high NUE)/C306 (low NUE). The mapping population, two parental genotypes and three check genotypes were evaluated under four different N levels (0, 60, 120, and 180 kg/ha) over three years. A genetic map containing 456 SNP markers (2571.38 cM length) was used for QTL analysis. Thirty six main effect QTLs (17 QTLs for NUE, 13 NUpE and 6 QTLs for NUtE) distributed on 12 chromosomes (1B, 1D, 2A, 2B, 3A, 4B, 5A, 5B, 5D, 6A, 6D, and 7A) were identified at 2.52–9.27 LOD scores. Individual QTLs explained 6.65–22.89% phenotypic variation. Multi-traits QTLs (Mt-QTLs) and epistatic QTLs involving first-order epistatic (QTL × QTL) interactions were also discovered. Candidate genes (CGs, as many as 737) were mined from QTL regions which were mainly involved in metabolic process, cellular process and catalytic activity, etc.; differential expression was observed for 49 CGs in roots and 34 in shoots. The CGs encoded important transcription factors, transporters, etc. having a role in NUE. QTLs and CGs reported in this study enriched the available knowledge. Seven QTLs (including three Mt-QTLs) and QTLs involved in six epistatic interactions are recommended for MAS for improvement of NUE in wheat. [ABSTRACT FROM AUTHOR]

An MIL-100 (Fe)/graphene oxide (GO) hybrid, a fairly-known composite, was made through a simple one-step procedure and played a highlighted role in the photo-induced oxidative functionalization of the benzylic C–H bond. To identify the given binary composite, various techniques were applied: FT-IR, P-XRD, SEM, nitrogen absorption–desorption analysis, TGA, TEM, and UV–Visible DRS spectra. Proportions of GO used within the structure of the prepared composite differently ranged from low to high amount, and the most optimized ratio met at 38.5% of GO as the most efficient catalyst. Additionally, the reaction ran in Glycerol/K2CO3 (2:1) as the optimal solvent. The elemental roles of O2·− and OH− were supposed to be the major ones for running a tandem oxidation-Knoevenagel reaction. The heterogeneity and reusability of the catalyst were also examined and confirmed after five successive runs. [ABSTRACT FROM AUTHOR]

Nitrogen (N) limitation to net primary production is widespread and influences the responsiveness of ecosystems to many components of global environmental change. Logic and both simple simulation (Vitousek and Fieldin in Biogeochemistry 46: 179–202, 1999) and analytical models (Menge in Ecosystems 14:519–532, 2011) demonstrate that the co-occurrence of losses of N in forms that organisms within an ecosystem cannot control and barriers to biological N fixation (BNF) that keep this process from responding to N deficiency are necessary for the development and persistence of N limitation. Models have focused on the continuous process of leaching losses of dissolved organic N in biologically unavailable forms, but here we use a simple simulation model to show that discontinuous losses of ammonium and nitrate, normally forms of N whose losses organisms can control, can be uncontrollable by organisms and can contribute to N limitation under realistic conditions. These discontinuous losses can be caused by temporal variation in precipitation or by ecosystem-level disturbance like harvest, fire, and windthrow. Temporal variation in precipitation is likely to increase and to become increasingly important in causing N losses as anthropogenic climate change proceeds. We also demonstrate that under the conditions simulated here, differentially intense grazing on N- and P-rich symbiotic N fixers is the most important barrier to the responsiveness of BNF to N deficiency. [ABSTRACT FROM AUTHOR]

Quantitative analyses of the nitrogen concentration in compound fertilizer were performed using laser-induced breakdown spectroscopy (LIBS). Thirty-two samples were used as a calibration set, and eight samples were used as a validation set. To eliminate the matrix effect, partial least-squares regression (PLSR) and least-squares support vector regression (LS-SVR) were used to establish models. For the partial least-squares regression model, the correlation coefficients for the calibration and prediction sets were 0.837 and 0.794, respectively. While using the LS-SVR method, the correlation coefficients for the calibration and prediction sets were improved to 0.994 and 0.993, respectively. Therefore, the LS-SVR method improved the analysis accuracy. The prediction mean absolute error was 0.023%. The results indicate that LIBS coupled with LS-SVR is a reliable and accurate method for determining the nitrogen concentration in compound fertilizer. [ABSTRACT FROM AUTHOR]

Lignin is essential for the characteristics and quality of timber. Nitrogen has significant effects on lignin contents in plants. Nitrogen has been found to affect wood quality in plantations and lignin content in plants. Caffeoyl-CoA 3-O-methyltransferase (CCoAOMT) is an important methyltransferase in lignin biosynthesis. However, the classification of woody plant CCoAOMT gene family members and the regulation mechanism of nitrogen are not clear. Bioinformatics methods were used to predict the members, classification, and transcriptional distribution of the CCoAOMT gene family in Populus trichocarpa. The results showed that there were five PtCCoAOMTs identified, and they could be divided into three sub-groups according to their structural and phylogenetic features. The results of tissue expression specificity analysis showed that: PtCCoAOMT1 was highly expressed in roots and internodes; PtCCoAOMT2 was highly expressed in roots, nodes, and internodes, PtCCoAOMT3 was highly expressed in stems; PtCCoAOMT4 was highly expressed in young leaves, and, PtCCoAOMT5 was highly expressed in roots. Different forms and concentrations of nitrogen had varying effects on the expression patterns of genes in different plant tissue types. The results of real-time PCR showed that the expression levels of PtCCoAOMT1 and PtCCoAOMT2 in stems increased significantly under different forms of nitrogen. PtCCoAOMT3 and PtCCoAOMT4 were induced by nitrate nitrogen in upper stems and lower leaves, respectively. PtCCoAOMT4 and PtCCoAOMT5 were induced by different concentrations of nitrate nitrogen in lower stems and roots, respectively. These results could provide valuable information for revealing the differences between functions and expression patterns of the various CCoAOMT gene family members under different forms and concentrations of exogenous nitrogen in poplar. [ABSTRACT FROM AUTHOR]

In this article, a simple and efficient method for the synthesis of highly porous monoliths based on glycidyl methacrylate (GMA) crosslinked with divinylbenzene (DVB) or ethylene glycol dimethacrylate (EGDMA) is presented. Redox-initiated polymerization in the external (oil) phase of a high internal phase emulsion (HIPE) is used. The use of the oil-soluble redox couple benzoyl peroxide/dimethyl-p-toluidine eliminates the need to heat the usually unstable GMA-based HIPEs during polymerization. The most striking feature of these cured GMA polyHIPEs is their open-cell, highly interconnected porous structure. The polyHIPEs crosslinked with EGDMA contain voids with a diameter of 10 to 13 µm, and the polyHIPEs crosslinked with DVB contain voids with a diameter of 10 to 22 µm. In both cases, the surfaces of the voids have a high density of windows with a diameter of 0.5 to 1 µm. Highly crosslinked poly(GMA-co-EGDMA) monoliths showed negligible volume shrinkage when heated to 200 °C. In order to obtain monoliths with ion-exchange groups on the surface of the pores for chromatography applications, functionalization with different multifunctional diamines was performed. FTIR spectroscopy and nitrogen content analysis were used to monitor the functionalization processes. [ABSTRACT FROM AUTHOR]

Inclusion compounds of nitrogen-containing aromatic chromophores 4,4′-bispyridylethylene (bpe) and 4,4′-azopyridine (apy) in the cavities of mesoporous metal-organic frameworks Cr–MIL-101 and Al–MIL-101 are prepared and characterized by elemental analysis and nitrogen adsorption methods with a goal of finding approaches to the design of solid photochromic materials combining the benefits of photochromes in liquid solutions (high quantum yields) and in solid states (increased resistance to photodegradation). Photochemical properties of these compounds are qualitatively studied. Compound apy@Al–MIL-101 exhibits higher photoactivity than polycrystalline apy. Three other inclusion compounds are not photoactive. Possible reasons of the lack of photoactivity in these compounds are discussed. [ABSTRACT FROM AUTHOR]

In this study, a novel magnetic mesoporous silica with yolk–shell structure (Fe3O4@Void@m.SiO2) was successfully synthesized via a polymer-template assisted method. The Fe3O4@Void@m.SiO2 was characterized by using FT-IR, EDS, SEM, TEM, VSM, PXRD and nitrogen adsorption–desorption analyses. The Fe3O4@Void@m.SiO2 nanocomposite showed high efficiency in adsorption of an organic dye and water pollutant called methylene blue (MB) with 98.2% removal capability. Furthermore, the effect of different parameters in the adsorption of MB was investigated. Different models of kinetic were examined and compared with each other. The recoverability and reusability of designed Fe3O4@Void@m.SiO2 material were also studied under applied conditions. [ABSTRACT FROM AUTHOR]

In this work were studied the fatty acids of the fruit from Ficus benjamina, which is a tree of the Moraceae family and is largely found in Brazil as an ornamental tree, normally used for afforestation in public ways and also for indoor residences. The fruit has a diameter around 1 cm which is appreciated by several types of birds. The lipids extraction from fruit was carried out with hexane reagent, and the fatty acids were evaluated by chromatography and also by thermal analysis. The thermal characterization was done in different purge gases and heating rates. The results obtained showed that the fatty acid has a light green colour wax with a high melting point. Chromatography analysis showed that the composition of the saturated and unsaturated fatty acids was 53.48 and 46.52%, respectively. The thermoanalytical study showed that this wax has several mass losses, which are dependent on the type of purge gas used. Details regarding their kinetic behaviour were acquired and showed that the analysis at nitrogen purge gas is very similar to that observed at carbon gas. [ABSTRACT FROM AUTHOR]

For the characterization of an epoxy resin composite material, the following analyses were performed: thermal analysis (TG/DTG/DTA) in nitrogen flow at five linear heating rates and under four quasi-isothermal temperature programs, coupled TG + FTIR analysis, DSC analysis in nitrogen flow, X-ray diffraction and FTIR spectroscopy. The processing of the TG data was performed by using Netzsch Thermokinetics—a software module for kinetic analysis. The dependence of the activation energy, evaluated by isoconversional methods, on the conversion degree shows that the investigated process is a complex one. The kinetic scheme and the corresponding kinetic parameters were determined by multivariate nonlinear regression program. The kinetic scheme and kinetic parameters thus obtained were used to calculate the TG curves corresponding to the quasi-isothermal temperature programs. A good agreement between the experimental and calculated TG curves has been found. The obtained results were used for the prediction of thermal lifetime of this material corresponding to some usage temperatures and to the 5% end-point criterion. [ABSTRACT FROM AUTHOR]

Fe/Co metal–organic frameworks (Fe/Co-MOFs) were synthesized by a solvothermal method using terephthalic acid (BDC) and N,N-dimethylformamide (DMF), and the removal of tetracycline (TC) was accomplished with high efficiency. We explored the influence of Co content on the characteristics of the bimetallic MOFs. The structures of the Fe/Co-MOFs were characterized by X-ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy (FTIR), and nitrogen physisorption analysis. The results showed that Co2+ was well loaded in the Fe-MOFs. Due to the different coordination behaviors of Co2+ and Fe3+ with BDC, the Fe/Co-MOFs formed a new 3D structure with a spike ball-like morphology. The morphology changed dramatically, leading to a large specific surface area, and the activity of the Lewis acid sites was greatly enhanced. Through FTIR and XPS analysis before and after adsorption, the adsorption process was mainly affected by coordination action. The largest TC adsorption capacity was observed when the Fe/Co ratio was equal to 1:3, and the saturated adsorption capacity was 139.8 mg g−1. [ABSTRACT FROM AUTHOR]

In this study, MIL-101(Fe), MIL-101(Fe,Cu), and graphene oxide (GO)/MIL-101(Fe,Cu) were synthesized to compose a novel sorbent. The adsorption properties of these three MOF-based composites were compared toward the removal of phosphate. Furthermore, the influencing factors including adsorption time, pH, temperature, and initial concentration on the adsorption capacity of phosphate on these materials as well as the reusability of the material were discussed. The structure of fabricated materials and the removal mechanism of phosphate on the composite material were analyzed by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), nitrogen adsorption-desorption analysis, and zeta potential. The results show that the maximum adsorption capacity of phosphate by the composite GO/MIL-101(Fe,Cu)-2% was 204.60 mg·g−1, which is higher than that of MIL-101(Fe,Cu) and MIL-101(Fe). likewise the specific surface area of GO/MIL-101(Fe,Cu)-2% is 778.11 m2/g is higher than that of MIL-101(Fe,Cuand MIL-101(Fe),which are 747.75 and 510.66 m2/g, respectively. The adsorption mechanism of phosphate is electrostatic attraction, forming coordination bonds and hydrogen bonds. The fabricated material is a promising adsorbent for the removal of phosphate with good reusability. [ABSTRACT FROM AUTHOR]

The presented work follows the theme of applied chemistry toward nanomaterials and multiphase functional systems of practical importance. Structural studies of nanocomposite materials are important due to the correlation between physicochemical/structural properties and their application potential. In this work, we report the fabrication and structural characterization of nanocomposite materials constituting noble metal (plasmonic) nanoparticles (AgNP and AuNP) dispersed on selected types of nanostructured solid hosts (nonporous silica, microporous activated carbon, chitosan biopolymer, and ordered mesoporous silica). The ability to maintain a dispersed state of colloidal precursors throughout their deposition on solid hosts was assessed. The influence of the carrier role in the formation and stabilization of nanometallic phases was evaluated taking into account the physicochemical and textural properties of the support surfaces. The size and shape of nanoobjects, clustering effects, interfacial properties, and stability of the immobilized nanophase were implemented by analyzing relevant parameters of SAXS analysis. The dimensional characteristic of the scatterers was evaluated by volume-weighted particle size distribution Dv(R). The detailed overall shape and maximal particle dimension were described by the analysis of pair distance distribution functions (PDDFs). The radius of gyration (Rg) from PDDF and Guinier approximation was calculated for illustrating the dimension of scattered heterogeneities in the investigated solids. The asymptotic behavior of a scattering curve and Porod theory were applied for determining the diffusion and quality of the interfacial surfaces. The size and morphology of nanoparticles in colloidal precursor solutions have been defined as spherical and bimodal in size (~ 6 nm and 20 nm). It was observed that the spherical shape and dispersed state of nanoparticles were achieved for all systems after deposition. However, the morphology of their final form was conditioned by the solid matrices. The particle properties from SAXS were correlated with properties determined by TEM and low-temperature nitrogen sorption analysis. Obtained results suggest good compatibility and correctness of SAXS data reading of nanocomposite systems and can be successfully applied for quick, nondestructive, and effective evaluation of structural properties of complex systems. [ABSTRACT FROM AUTHOR]

The paper investigates the reason for the cracking and leaking of stainless-steel (SS) tanks used to store processed hot water in rice boiling and husking plants. A detailed analysis of tank specimen samples using radiography, optical metallography, scanning electron microscopy, EDAX reveals that stress corrosion cracking (SCC) is the prime reason for the failure. The presence of favorable microstructure, environment and stress promoted the nucleation and propagation of SCC in the tank weldment. The evolution of the microstructure in the selected stainless grade was studied and discussed using Scheffler–Delong diagram. The formation of martensite in low nickel, high nitrogen austenitic stainless steel was observed to significantly influence the mechanical properties and promote SCC. The decreased pitting corrosion resistance of the material compared to SS 316 alloy was an important factor in the initiation of pits which acted as nucleation sites for SCC. [ABSTRACT FROM AUTHOR]

Aerobic denitrifiers have the potential to reduce nitrate in polluted water under aerobic conditions. A salt-tolerant aerobic denitrifier was newly isolated and identified as Vibrio spp. AD2 from a marine recirculating aquaculture system, in which denitrification performance was investigated via single-factor experiment, Box–Behnken experiment, and nitrogen balance analysis. Nitrate reductase genes were identified by polymerase chain reaction. Results showed that strain AD2 removed 98.9% of nitrate-nitrogen (NO3−-N) with an initial concentration about 100 mg·L−1 in 48 h without nitrite-nitrogen (NO2−-N) accumulation. Nitrogen balance indicated that approximately 17.5% of the initial NO3−-N was utilized for bacteria synthesis themselves, 4.02% was converted to organic nitrogen, 39.8% was converted to nitrous oxide (N2O), and 31.1% was converted to nitrogen (N2). Response surface methodology experiment showed that the maximum removal of total nitrogen (TN) occurred under the condition of C/N ratio 11.5, shaking speed 127.9 rpm, and temperature 30.8 °C. Sequence amplification indicated that the denitrification genes, napA and nirS, were present in strain AD2. These results indicated that the strain AD2 has potential applications for removing NO3−-N from high-salinity (3%) wastewater. [ABSTRACT FROM AUTHOR]

Isatis indigotica Fort. is a popular herb in traditional Chinese medicine. It possesses pharmacological activities against various diseases, particularly leukemia. Indigoid alkaloids are its main bioactive ingredients. A relatively low nitrogen supply increases indigoid content in I. indigotica leaves, yet the mechanisms that regulate indigoid biosynthesis are unknown. To uncover regulatory mechanisms, we performed transcriptome sequencing of leaf samples from I. indigotica exposed to deficient (0 mM), low (7.5 mM), and high (15 mM) concentrations of NO3−. We generated 38,990 unigenes with an N50 value of 1923 bp, of which 33,007 unigenes (84.65%) were annotated in at least one database. In comparison with deficient N, we identified 6911 and 4845 differentially expressed genes (DEGs) in high N and low N. Cluster analysis of these DEGs showed a unique expression pattern in the N-supplied compared with the N-free condition. Twenty-one genes related to nitrogen uptake, transport, and assimilation were highly expressed in N-deficient conditions. Further, 63 putative genes that encode for enzymes involved in indigoid biosynthesis in I. indigotica leaf were identified and analyzed. Thirteen genes involved in indole modification were expressed more highly in low N; their high expression level may explain the increase in indigoid alkaloids in low N. Notably, phylogenetic analysis showed that IiTSA3 may relate to genes involved in indole heterocycle biosynthesis. Additionally, 491 differentially expressed TFs were also identified. Our findings will enrich gene resources for elucidating the molecular mechanisms of indigoid alkaloid biosynthesis in I. indigotica leaves under different nitrogen supplies. [ABSTRACT FROM AUTHOR]

Nitric oxide (NO) and its by-products are important biological signals in human physiology and pathology particularly in the vascular and immune systems. Thus, in situ determination of the NO-related molecule (NOx) levels using embedded sensors is of high importance particularly in the context of cellular biocompatibility testing. However, NOx analytical reference method dedicated to the evaluation of biomaterial biocompatibility testing is lacking. Herein, we demonstrate a PAPA-NONOate-based reference method for the calibration of NOx sensors. After, the validation of this reference method and its potentialities were demonstrated for the detection of the oxidative stress-related NO secretion of vascular endothelial cells in a 3D tissue issued from 3D printing. Such NOx detection method can be an integral part of cell response to biomaterials. [ABSTRACT FROM AUTHOR]

Selective removal of lignin and other recalcitrant compounds, collectively registered as acid-unhyrolyzable residue (AUR), results in bleaching of leaf litter, but the importance of bleaching in decomposition processes on forest soil has not been fully evaluated. The aims of this study were to elucidate the occurrence of bleached area in decomposing leaf litter and to compare chemical composition between bleached and nonbleached portions in a subtropical forest in Japan. Field incubation of leaf litter was performed over an 18-month period with the litterbag method. The decomposition processes during the first 9 month were characterized by the relatively rapid mass loss and increase of bleached area, whereas the mass loss was slowed down and the bleached area decreased thereafter. Mass loss of leaf tissues was faster and AUR content was lower in bleached than in nonbleached portions, indicating the acceleration of mass loss in bleached leaf tissues by the selective decomposition of recalcitrant compounds. The decrease in carbonyl-C in the bleached portions was associated with the increase of extractable nitrogen. The results suggest that the bleaching plays a dominant role in the transformation and turnover of organic compounds and nitrogen in decomposing leaf litter. [ABSTRACT FROM AUTHOR]

To address the environmental concerns and increases the total factor productivity to the farmers simultaneously, forces the breeders to develop the genotypes adapted to low input agriculture especially, low nitrogen (N) management practices. However, inadequate knowledge about the genetics of plant response to the low nutrient regime is complicating the breeding procedure. Therefore, the present study was designed to work out the genetics of nitrogen use efficiency (NUE) and its component traits under N-limiting (LN) environment in Indian wheat germplasm. Analysis of variance showed the presence of a large amount of genetic variability for NUE as well as its component traits. Combining ability analysis for N efficiency under LN indicated the importance of both additive and nonadditive gene action in their inheritance. Additive gene action was more important for shoot dry weight, NUE, and maximum root length. Improvement in these traits can be achieved by targeting the selection in early fixed lines (F4–F5) in the breeding population created by crossing good general combining ability (GCA) lines such as DPW 621-50 and HD2967/HD3024. Whereas, root dry weight (RDW), gram N in shoot (gN), nitrogen uptake efficiency (NUpE) are influenced by nonadditive gene effects which can be improved either through population improvement programme or hybrid breeding approach. Recurrent selection can be quite useful in developing the desirable recombinants for RDW, gN, NUpE, and nitrogen utilization efficiency from crosses with high specific combining ability (SCA) effects and involving high × low GCA parents. [ABSTRACT FROM AUTHOR]

Cooling of machining operations by liquid nitrogen is a promising approach for reducing cutting temperatures, increasing tool life and improving the workpiece surface integrity. Unfortunately, the cooling fluid tends to evaporate within the supply channel. This induces process variations and hinders the use of nitrogen cooling in commercial applications. In this work, the coolant is applied via the tool's rake face during orthogonal turning of Ti-6Al-4V. The effect of a nitrogen supply pressure adjustment and a subcooler usage—proposed here for the first time for machining—is analyzed in terms of process forces, tool temperatures and wear patterns, taken dry cutting as a reference. Thereby, reliable cooling strategies are identified for cryogenic cutting. [ABSTRACT FROM AUTHOR]

A simple microwave method was employed to prepare silica-doped mesoporous zirconia nanoparticles, SiO2/ZrO2 (SiZr) catalysts under various Si amount and then characterized by X-ray diffraction, nitrogen adsorption–desorption analyses, Fourier-transform infrared, electron spin resonance, ultraviolet–visible diffuse reflectance spectroscopy and photoluminescence analyses. The lower amount of Si fully stabilized the ZrO2 in the tetragonal phase (t-ZrO2), but the higher amount of Si occupied oxygen vacancies (OV) in the SiZr lattice to disrupt the catalysts with introduce low content of monoclinic phase. The catalyst activity towards on photodegradation of 2-chlorophenol (2-CP) was ranked in the following order: 1SiZr (92%) > TiO2 (73%) > 2SiZr (67%) > 3SiZr (64%) > 4SiZr (56%) > ZrO2 (51%). This result demonstrated that 1SiZr gave the highest degradation percentage of 10 mg L−1 2-CP at pH 5 using 0.375 g L−1 catalyst under visible light irradation within 4 h. The highest photoactivity of 1SiZr is due to the larger surface area and crystallite size, which resulted in a good surface contact with light and thus accelerated the photocatalytic activity. Additionally, the highest amount of OV possesed by 1 SiZr effectively suppressed the electron–hole recombination by acting as an electron acceptors, which consequently affected the t-ZrO2 stabilization as well as the catalytic activity. The kinetics of photocatalytic degradation of 2-CP correlated with pseudo-first order model, with the surface reaction as the controlling step. The photogenerated hole was the most active species as confirmed by effect of scavenger study. The 1SiZr maintained the photocatalytic activities after five runs and has a great capability in degrading of various phenols derivatives, indicating its potential use in the phenol-based wastewater treatment. [ABSTRACT FROM AUTHOR]

Two kinds of hydroxypropyl β-cyclodextrin nanohybrid monoliths were synthesized and applied in capillary electrochromatography with UV detection. One column was fabricated by concurrently using glycidyl methacrylate-bonded hydroxypropyl β-cyclodextrin (GMA-HP-β-CD), sodium 3-mercaptopropanesulphonate, and alkoxysilanes in the "one-pot" process. The other was prepared by free radical polymerization of GMA-HP-β-CD, vinylmethylcyclosiloxane, ethylene dimethacrylate, and 2-acrylamido-2-methyl propane sulfonic acid. Compared to the former hybrid monolith, the latter one displayed improved enantiomeric separation. For ten adrenergic drugs, six anticholinergic drugs, two antidepressants, six azoles, and one antihistamine enantiomeric separation was obtained on the monolith synthesized by free radical polymerization. Twelve out of twenty-five drugs were baseline-separated. Especially, anisodamine with two chiral centers was successfully separated with resolution values of 3.06, 2.11, and 2.17. The nanohybrid monoliths were characterized by optical microscopy, scanning electron microscopy, FT-IR, nitrogen adsorption analysis, and thermogravimetric analysis. Relative standard deviation values less than 5% were obtained through run-to-run, day-to-day, and column-to-column investigations (n = 3). [ABSTRACT FROM AUTHOR]

Tantalum bulk has been implanted by nitrogen ions at an energy30 keV and at various doses of 1 × 1017, 3 × 1017, and 10 × 1017 ions/cm2. As a result, thin films are rough; their morphology and stochastic properties have been investigated. The monofractal analysis is done for unimplanted and implanted samples based on the statistical analysis conception. The correlation function and also the correlation length of the samples have been studied. Also, the power spectral density, the dimension of the fractal, the distribution of height, and the skewness and kurtosis (the higher-order moments) of the surface height have been investigated. The results show the deviation of height distribution from the gaussian one. The measurement of jagged and irregularity of samples have been investigated by calculating the roughness exponent and fractal dimensions. The rough samples which have been produced by ion bombardment have the self-affine fractal properties. [ABSTRACT FROM AUTHOR]

The international trade in lion (Panthera leo) products, particularly bone, has increased substantially over the last decade. The Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) has established a zero-export quota for wild-origin lion bones. Whilst the trade of lion bone is permittable from captive-bred South African populations, there is no established method to differentiate between captive and wild-sourced lion derivatives in trade. This study acts as a preliminary investigation, by examining the stable carbon (δ13C) and nitrogen (δ15N) isotope composition of hair from wild and captive lion populations as well as wild prey animals in South Africa, to judge the accuracy and applicability of this method for future bone analysis. Isotopic values for δ15N are found to be significantly enriched in some wild populations, however it is not possible to discriminate between captive and wild populations using δ13C analysis alone. Using the classification algorithm k-Nearest Neighbour, the origin of simulated data was identified with 70% accuracy. When using the model to test the origin of seized samples, 63% were classified as of wild origin. Our study indicates the potential for stable isotope analysis to discriminate between captive and wild populations. Additional study of captive husbandry, and analysis of bone samples from populations of a known origin and feeding regime is recommended to improve the utility of this method for maintaining transparency in trade. [ABSTRACT FROM AUTHOR]

Hexagonal boron nitride (h-BN) is introduced as a 2D scaffold during the preparation of molecularly imprinted polymers (MIPs). The MIPs were prepared from deep eutectic solvents (DES) or from DES containing h-BN, crosslinking agent (ethylene glycoldimethacrylate), initiator (AIBN), porogen (methanol), and template (quercetin). The recognition site of the monomer is protected by the hydrogen bond of the DES before the MIP is polymerized. The formation of the final MIP was analyzed theoretically using density-functional theory. The nanoparticles were characterized by scanning electron microscopy, nitrogen sorption analysis, thermogravimetry and Fourier transform infrared spectroscopy. The introduction of h-BN resulted in an increase in the surface area of the nanoparticles. They were applied as a solid phase extraction sorbent for the extraction of flavonoids (specifically of quercetin, isorhamnetin and kaempferol) from Ginkgo biloba leaves. Following extraction with ethanol, they were quantified by HPLC. The new sorbent has distinctly improved recognition capability for flavonoids compared to conventional MIP nanoparticles. [ABSTRACT FROM AUTHOR]

The species composition, abundance, biomass, and distribution of zooplankton were studied on the shelf and slope of the northwestern Laptev Sea and the shelf of the East Siberian Sea in summer 2015. The trophic status of common zooplankton and fish species, as well as their position in the food webs of these two seas, has been determined based on stable carbon and nitrogen isotope analyses (δ13C and δ15N). Data of both stomach content and stable isotope analyses show significant age-related variations in the trophic status of the Arctic cod Boreogadus saida, which is the dominant fish species. [ABSTRACT FROM AUTHOR]

In this study, a low temperature precipitation method was applied to prepare BiOX (X = Cl, Br and I) nanostructures using HCl, HBr and HI as halogen sources. The as-prepared samples were characterized by various techniques such as X-ray diffraction, field emission scanning electron microscopy, energy dispersive spectroscopy, Fourier-transform infrared spectroscopy, diffuse reflectance spectroscopy and nitrogen adsorption–desorption analysis. The photoactivity of BiOX samples to degrade rhodamine B (RhB) molecules in aqueous solution was investigated under white LED irradiation. The results indicated that BiOCl exhibits a higher photodegradation performance in comparison with BiOBr and BiOI. Ninety six percent of the RhB molecules was degraded over BiOCl after 25 min light irradiation, whereas under the same conditions, the degradation efficiencies of BiOBr and BiOI samples are 62 and 24%, respectively. The enhanced photodegradation activity of BiOCl is ascribed to the higher specific surface area which increases the physical adsorption of RhB molecules on the photocatalyst surface. Moreover, the photodegradation mechanism and the main radical species in the degradation reactions over BiOCl were investigated. [ABSTRACT FROM AUTHOR]

А quantitative analysis method to determine the total nitrogen content in monoammonium phosphate (MAP) fertilizer using visible-near infrared (Vis-NIR) spectroscopy and least squares support vector machine (LS-SVM) is proposed. Sample set partitioning based on the joint x–y distance (SPXY) was used to select the calibration set. Fourteen spectral pre-processing methods were then employed to deal with the spectral data including Savitzky–Golay (SG) smoothing, fi rst derivative (D1) and second derivative (D2) with SG smoothing, multiplicative scatter correction (MSC), standard normal variate (SNV), wavelet, and combination thereof. Next, the LS-SVM model with radial basis function kernel was established with the best pre-processing method, and its performance was compared with that of partial least squares (PLS) model. The results revealed LS-SVM calibration with the discrete wavelet transform provided the best prediction for total nitrogen content in MAP fertilizer, yielding R2, root mean square error of prediction (RMSEP), and ratio of performance to deviation (RPD) values of 0.91, 0.101, and 3.34, respectively. [ABSTRACT FROM AUTHOR]

This paper describes the utilisation of urea as a single chemical agent to obtain deproteinised high ammoniated natural rubber latex (HA-NRL). The role of urea in HA-NRL deproteinisation was further investigated by employing two different concentrations of urea solution which are low (0.01–0.05%) and high (1.0–5.0%) concentrations. The study assessed the potential usage of urea as a single denaturing agent in the presence of neither stabilising agent nor additives during the deproteinisation process. The effect of different urea concentrations on properties of deproteinised NRL was further scrutinised by using sodium dodecyl sulphate–polyacrylamide gel electrophoresis (SDS-PAGE), nitrogen content analysis, extractable protein (EP) content, Zeta potential, attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectroscopy and physical strength. The presence of residual urea is pertinent as the concentration of urea increases while contributing to the increase of total nitrogen content in the resultant film. Leaching the film with hot water is sufficient to remove the residual urea as supported by an ATR-FTIR analysis. Initial exploratory data analysis of low and high urea concentrations on the effect of nitrogen content, EP, surface charge properties of latex and green strength of the deproteinised NRL were evaluated and their relation to each factor was further discussed. Based on the initial findings, urea was observed to be less effective as a single denaturant. Nonetheless, the properties of the deproteinised HA-NRL treated with urea were revealed to be markedly influenced by the urea concentration. [ABSTRACT FROM AUTHOR]

Human activities reshape the global nitrogen (N) cycle and affect environment and human health through reactive nitrogen (Nr) loss during production and consumption. In urbanized regions, the N cycle is greatly mediated by complex interactions between human and natural factors. However, the variations in sources, magnitude, spatiotemporal patterns and drivers of Nr flows remain unclear. Here we show by model simulations, anthropogenic perturbations not only intensify Nr input to sustain increasing demands for production and consumption in Guangzhou city, China, but also greatly change the Nr distribution pattern in the urban system, showing a substantial Nr enrichment in the atmosphere and a relatively low retention capacity of Nr in the terrestrial system. Our results highlight the strong anthropogenic effect of urban systems on the N cycle to suggest sustainable human activity changes to harmonize the relationship between Nr behaviors and human drivers. There lacks research to figure out the variations in sources, magnitude, and spatiotemporal patterns of Nr flows in urban system. Here the authors develop a coupled human-natural urban nitrogen flow analysis model and show that anthropogenic perturbations not only intensify Nr input to sustain increasing demands for production and consumption of cities, but also greatly change the Nr distribution pattern in the urban system. [ABSTRACT FROM AUTHOR]

The potential for nitrogen attenuation in anoxic groundwater by examining the concentration and distribution patterns of electron acceptors, electron donors and microbiological parameters was assessed. Research was carried out for 25 monitoring bores in two anoxic alluvial aquifers Kovin-Dubovac and Knićanin-Čenta during the four years monitoring period (2010–2013). Nitrate and nitrite concentrations were mostly undetectable while ammonium, ferrous and total organic carbon concentrations were increased with sporadic sulfide appearance. Piper diagrams qualified these groundwaters as predominantly Ca2+(Mg2+)– type. By Alekin classification waters belong to type. The multiple electron donors (organic carbon, iron minerals and sulfide) and spatial and temporal variability of alternative electron acceptors proved to be determining factors of dominant nitrogen reduction path way. Concentrations trends of chemical and microbiological parameters revealed the conditions suitable for nitrogen conservation and they are presented via developed maps and BART test results. Statistical analysis was evaluated by Principal Component Analysis and Cluster Dendograms. [ABSTRACT FROM AUTHOR]

Nanoscale composite materials based on titanium dioxide, sulphur, and carbons were obtained. The samples were characterized using X-ray powder diffraction, scanning electron microscopy, energy-dispersive X-ray spectroscopy, transmission electron microscopy, Brunauer–Emmett–Teller and Barret–Joiner–Halenda methods, electron paramagnetic resonance spectroscopy, and ultraviolet–visible and infrared spectroscopy. X-ray powder diffraction revealed the phase of anatase in all composites and appearance of rutile phase for samples with high sulphur content. It was established that composites consist of nanoparticles ca. 6–10 nm. Analysis of nitrogen adsorption–desorption isotherms for the synthesized samples showed the presence of a hysteresis loop which is the evidence for mesoporous structure of the powders. Absorption spectra of nanocomposites showed a bathochromic shift compared with the absorption band of pure TiO2. It was found that modification of titanium dioxide with sulphur and carbons leads to bandgap narrowing of composites. Nanocomposite samples showed higher photocatalytic activity in the destruction of safranin T under ultraviolet and visible irradiation compared to pure titanium dioxide. It can be connected with the participation of additives in the inhibition of electron–hole recombination, prolongation of charges lifetime, increasing of efficiency of interfacial charge separation, and formation of doping electronic states. [ABSTRACT FROM AUTHOR]

Imidazolinium l-tartrate (IMLT) crystals and l-histidine-doped IMLT crystals were grown by slow evaporation technique at room temperature. The powder x-ray diffraction technique confirms the lattice parameters and shifts in the peak positions attributed to the dopant l-histidine. The Fourier transform infrared (FTIR) spectrum reveals the assignments of characteristic bondings present in the grown crystals. The frequency-dependent dielectric constant and dielectric loss of pure and l-histidine-doped IMLT crystals have been investigated by the dielectric measurements. Doping has improved the optical parameters and was studied using UV–Vis-near infrared (NIR) spectral studies. The cut-off wavelengths of pure and 1 mol.% l-histidine-doped IMLT crystals were observed at 234 nm and 229 nm, respectively. The etching study examines the growth mechanism and surface morphology of the pure and l-histidine-doped IMLT crystals. The carbon-hydrogen-nitrogen (CHN) analysis conveys the percentage of carbon, hydrogen and nitrogen elements present in pure and l-histidine-doped IMLT crystals. The consequences of doping l-histidine in IMLT single crystal and their dominance in various properties of the crystal grown in aqueous solution by slow evaporation technique have been explored. [ABSTRACT FROM AUTHOR]

The goat's rue rhizobia (Neorhizobium galegae) represent a convenient model to study the evolution and speciation of symbiotic bacteria. This rhizobial species is composed of two biovars (bv. orientalis and bv. officinalis), which form N2-fixing nodules with certain species of goat's rue (Galega orientalis and G. officinalis). The cross-inoculation between them results in the formation of nodules unable to fix nitrogen. On the basis of the data on the whole-genome sequencing, we studied the nucleotide polymorphism of 11 N. galegae strains isolated from the North Caucasus ecosystems, where G. orientalis has higher diversity than G. officinalis. The low level of differences in the polymorphism within the group of the sym genes in comparison with the nonsymbiotic genes can be associated with the active participation of host plants in the evolution of rhizobia. The intragenic polymorphism of bv. orientalis proved to be significantly higher than that of bv. officinalis. The level of polymorphism of nonsymbiotic genes was lower than that of the symbiotic genes, which are functionally more homogeneous. The divergence of the nitrogen fixation genes (nif/fix) is more pronounced than that of the nodule formation genes (nod) in the N. galegae biovars. These facts indicate the leading role of the host-specific nitrogen fixation in the evolution of the studied rizhobial species. [ABSTRACT FROM AUTHOR]

A Pd catalyst supported on a composite containing nitrogen-doped carbon-modified titanium oxides (Pd/NC-Ti-O), and was prepared for formic acid electrooxidation. According to structure and morphology characterizations, NC-Ti-O consists of a nitrogen-doped carbon, TiO2, Ti2O3, and Ti2O, and the Pd/NC-Ti-O catalyst has a smaller particle size and more uniform dispersion as compared to the Pd/Ti4O7 catalyst. Electrochemical measurements displayed that the Pd/NC-Ti-O catalyst possesses a better electrocatalytic activity and stability towards the electrooxidation of formic acid than Pd/Ti4O7. The improvement of catalytic activity is mainly ascribed to the higher content of metallic Pd and stronger resistance to CO poisoning caused by NC-Ti-O. [ABSTRACT FROM AUTHOR]

Using stable isotope analysis of nitrogen, for the first time the hypothesis on different sources of inorganic nutrients for two groups of littoral algae in Lake Baikal was confirmed. Strongly attached filamentous algae of genus Ulothrix, which developed in the wave-braking zone at depth 0.5 m, and loosely attached filamentous algae of genus Spirogyra, which developed in deeper layers 3.0–5.0 m in a low-turbulence zone, get inorganic nutrients presumably from surface discharge and groundwater inputs, respectively. Besides, stoichiometric ratios C:N and N:P in biomass of the algae indicated that growth of Spirogyra in Lake Baikal was likely limited by nitrogen, while growth of Ulothrix was limited by phosphorus. [ABSTRACT FROM AUTHOR]