Nitrogen Trace Research Articles

Maximizing olefin production via steam cracking of distilled pyrolysis oils from difficult-to-recycle municipal plastic waste and marine litter

Plastic waste is steadily polluting oceans and environments. Even if collected, most waste is still predominantly incinerated for energy recovery at the cost of CO2. Chemical recycling can contribute to the transition towards a circular economy with pyrolysis combined with steam cracking being the favored recycling option for the time being. However, today, the high variety and contamination of real waste remains the biggest challenge. This is especially relevant for waste fractions which are difficult or even impossible to recycle mechanically such as highly mixed municipal plastic waste or marine litter. In this work, we studied the detailed composition and the steam cracking performance of distilled pyrolysis oil fractions in the naphtha-range of two highly relevant waste fractions: mixed municipal plastic waste (MPW) considered unsuitable for mechanical recycling and marine litter (ML) collected from the sea bottom. Advanced analytical techniques including comprehensive two-dimensional gas chromatography (GC × GC) coupled with various detectors and inductively coupled plasma – mass spectrometry (ICP-MS) were applied to characterize the feedstocks and to understand how their properties affect the steam cracking performance. Both waste-derived naphtha fractions were rich in olefins and aromatics (~70% in MPW naphtha and ~51% in ML naphtha) next to traces of nitrogen, oxygen, chlorine and metals. ICP-MS analyses showed that sodium, potassium, silicon and iron were the most crucial metals that should be removed in further upgrading steps. Steam cracking of the waste-derived naphtha fractions resulted in lower light olefin yields compared to fossil naphtha used as benchmark, due to secondary reactions of aromatics and olefins. Coke formation of ML naphtha was slightly increased compared to fossil naphtha (+ ~50%), while that of MPW naphtha was more than ~180% higher. It was concluded that mild upgrading of the waste-derived naphtha fractions or dilution with fossil feedstocks is sufficient to provide feedstocks suitable for industrial steam cracking.

Air Quality during the COVID–19 Lockdown and Unlock Periods in India Analyzed Using Satellite and Ground-based Measurements

A nationwide lockdown was imposed in India from 24 March 2020 to 31 May 2020 to contain the spread of COVID-19. The lockdown has changed the atmospheric pollution across the continents. Here, we analyze the changes in two most important air quality related trace gases, nitrogen dioxide (NO2) and tropospheric ozone (O3) from satellite and surface observations, during the lockdown (April–May 2020) and unlock periods (June–September 2020) in India, to examine the baseline emissions when anthropogenic sources were significantly reduced. We use the Bayesian statistics to find the changes in these trace gas concentrations in different time periods. There is a strong reduction in NO2 during the lockdown as public transport and industries were shut during that period. The largest changes are found in IGP (Indo-Gangetic Plain), and industrial and mining areas in Eastern India. The changes are small in the hilly regions, where the concentrations of these trace gases are also very small (0–1 × 1015 molec./cm2). In addition, a corresponding increase in the concentrations of tropospheric O3 is observed during the period. The analyses over cities show that there is a large decrease in NO2 in Delhi (36%), Bangalore (21%) and Ahmedabad (21%). As the lockdown restrictions were eased during the unlock period, the concentrations of NO2 gradually increased and ozone deceased in most regions. Therefore, this study suggests that pollution control measures should be prioritized, ensuring strict regulations to control the source of anthropogenic pollutants, particularly from the transport and industrial sectors.Highlights• Most cities show a reduction up to 15% of NO2 during the lockdown• The unlock periods show again an increase of about 40–50% in NO2• An increase in tropospheric O3 is observed together with the decrease in NO2Supplementary InformationThe online version contains supplementary material available at 10.1007/s40710-022-00585-9.

Activation effect of soil available nitrogen, manganese and cobalt after addition of different fumigants

Soil fumigation is a well-established method for controlling soil-borne diseases. Better quantification of soil available nitrogen and trace elements may provide recommendations on the safe and effective application of soil fumigants. The effects of four fumigants on the available soil nitrogen and trace elements (including Mn, Co, Ni, Cu, Zn and Cd) were investigated in the laboratory incubation with agricultural soil. The results showed that soil fumigation increased soil mineral nitrogen and available Mn, Co, Ni. A significant increase of soil NH4 +-N and available Mn was observed in all fumigation treatments. Chloropicrin treatments showed the largest increase of soil NH4 +-N. In addition, chloropicrin and dazomet increased Mn and Co to a greater extent than dimethyl disulfide and 1,3-dichloropropene in soil. Available Mn content after chloropicrin fumigation has increased by 2.2 times compared with control treatments, and available Co content in dazomet treatments is also 2.8 times more than untreated control. In fumigated soil, the steady increase of soil available elements is beneficial to nutrient uptake by plants. Soil fumigation created an activation effect on soil mineral nitrogen and available trace elements, which may increase their bioavailability to plants and promote plant growth.

Study on characterization of bio-oil derived from sugarcane bagasse (Saccharum barberi) for application as biofuel

Abstract Lignocellulosic biomass especially, sugarcane bagasse Saccharum barberi sp., appears to be a more suitable material for partial substitution of transport fuel (diesel) than Saccharum officinarum sp., due to its structural similarity to transport fuel (diesel). Besides that, less research has been implemented on this type of species. Bio-oil can be implemented as biodiesel by processing it further using chemical reactions such as hydrodeoxygenation and cracking with zeolite catalyst. Hence, the purpose of this study is to determine the compatibility of pyrolytic bio-oil produced from Saccharum barberi sp. in comparison with S. officinarum sp. for use as transport fuel (diesel) in automotive applications. This purpose can be accomplished by comparing the oil’s bio-physiochemical properties for both species. The experiment is conducted on a bench-scale on which bio-oil of Saccharum barberi sp. is secured from the catalytic pyrolysis process at a temperature of 500°C and heating rate of 50°C/min with the addition of ZSM-Zeolite catalyst. Thermogravimetric analysis of Saccharum barberi sp. reveals that cellulose is more reactive than lignin, evidenced by the high percentage of weight loss at temperatures ranging from 251°C to 390°C. The high contents of carbon (40.7%) and hydrogen (6.50%), as well as slight traces of sulphur (0.08%) and nitrogen (0.85%), in bio-oil (Saccharum barberi sp.) indicate that it is conceivable to be partially used for replacement in biofuel production. Overall physiochemical properties reveal that Saccharum barberi sp. shows more potential than S. officinarum sp. Gas chromatography–mass spectrometry analysis reveals that bio-oil consists of high amounts of aromatic hydrocarbon (26.2%), phenol (14.8%) and furfural (13.0%) in comparison to S. officinarum sp. Biofuel was produced from sugarcane bagasse (Saccharum barberi sp.) in a bench-scale pyrolysis reactor at 500°C using a zeolite catalyst. Measured properties of the biofuel make it suitable for partial substitution of diesel in transport fuel.

Legacy nitrate and trace metal (Mn, Ni, As, Cd, U) pollution in anaerobic groundwater: Quantifying potential health risk from “the other nitrate problem”

Denitrification in soils and aquifers sustains low nitrate concentrations in many anaerobic groundwaters despite massive inputs of N from agriculture. However, this ecosystem service sometimes comes at the cost of trace metal mobilization and concerns have been raised that denitrification in anaerobic groundwater may lead to trace metal contamination. But it remains unclear, if denitrification must necessarily result in trace metal concentrations that are potentially harmful for humans. For example, formation of iron(oxy)hydroxides after the reaction of nitrate with pyrite may reduce rather than increase the mobility of certain trace metals in aquifers. We quantified the potential health risk resulting from denitrification-associated trace metal pollution (Mn, Ni, As, Cd, U) in anaerobic groundwater with different degrees of nitrate pollution in >800 wells located in Northern Germany. Overall, observed rates of violations of legal quality standards for U, As and Cd are moderate in the study area (<10% of all wells) but elevated for Mn (>50%), which is a common contaminant under the often anaerobic conditions in the study area. However, in groundwater where denitrification had partially proceeded, the risk for drinking water standard violations was higher for Ni, Cd and U (up to a factor of 4 for Ni) as compared to anaerobic groundwater without denitrification, but lower for Mn and As. Especially poorly buffered groundwaters with pH < 5.5 are at risk of Ni and Cd contamination resulting from denitrification, while the opposite is true for Mn and U. Thus, we establish a clear linkage between nitrogen biogeochemistry and trace metal mobility and show how perturbations of groundwater redox and pH conditions by nitrate can further deteriorate groundwater quality. In addition, we find that the combination of oxygen concentrations of lower than 1 mg L−1, and nitrate concentrations above 1 mg L−1 allows for identification of denitrification (as evidenced by excess N2 in groundwater) with 90% accuracy. The methodology developed herein can be used to inform water treatment planning about potential trace metal contamination when drinking water should be produced from anaerobic aquifers beneath agricultural landscapes.

Tunable Ti3+-Mediated Charge Carrier Dynamics of Atomic Layer Deposition-Grown Amorphous TiO2

Amorphous titania (am.-TiO2) has gained wide interest in the field of photocatalysis, thanks to exceptional disorder-mediated optical and electrical properties compared to crystalline TiO2. Here, we study the effects of intrinsic Ti3+ and nitrogen defects in am.-TiO2 thin films via the atomic layer deposition (ALD) chemistry of tetrakis(dimethylamido)titanium(IV) (TDMAT) and H2O precursors at growth temperatures of 100–200 °C. X-ray photoelectron spectroscopy (XPS) and computational analysis allow us to identify structural disorder-induced penta- and heptacoordinated Ti4+ ions (Ti5/7c4+), which are related to the formation of Ti3+ defects in am.-TiO2. The Ti3+-rich ALD-grown am.-TiO2 has stoichiometric composition, which is explained by the formation of interstitial peroxo species with oxygen vacancies. The occupation of Ti3+ 3d in-gap states increases with the ALD growth temperature, inducing both visible-light absorption and electrical conductivity via the polaron hopping mechanism. At 200 °C, the in-gap states become fully occupied extending the lifetime of photoexcited charge carriers from the picosecond to the nanosecond time domain. Nitrogen traces from the TDMAT precursor had no effect on optical properties and only little on charge transfer properties. These results provide insights into the charge transfer properties of ALD-grown am.-TiO2 that are essential to the performance of protective photoelectrode coatings in photoelectrochemical solar fuel reactors.

Purification of hydrogen from natural gas/hydrogen pipeline mixtures

• A six-bed PSA cycle is proposed for the purification of hydrogen/natural gas mixture. • A three adsorbent layered bed is able to handle realistic natural gas mixtures. • High purity hydrogen (>99%) was obtained for hydrogen feed concentrations of 5–30%. • PSA compares well with an electrolyzer in providing hydrogen to a refueling station. There is an increasing global attention toward hydrogen as a green energy carrier, primarily because of the environmental concerns associated with global warming issues. It is expected that the produced hydrogen from various sources may be injected to the natural gas grid for economical transportation and use. One interesting option is to evaluate technologies for extracting the hydrogen from the natural gas pipeline for applications using high purity hydrogen. However, natural gas is a complex mixture including CH 4 , C 2 H 6 , CO 2 , N 2 and trace amounts of C 3 -C 6 hydrocarbons. This function requires a natural gas/hydrogen separation technology which must not only operate with low capital and energy cost, but must also provide hydrogen of sufficient purity. The goal of current work therefore was to take a mixture of hydrogen/natural gas of representative concentrations and produce high purity hydrogen using a bespoke pressure swing adsorption (PSA) cycle. A six-bed PSA system with 12 steps was developed and simulated in Aspen Adsorption software to this end. A three-layered adsorption column was designed to capture different groups of components of the mixture selectively within each layer. Informed by measured and literature equilibrium isotherm data, silica gel was chosen as the pre-layer to remove heavy hydrocarbon components and most of the CO 2 ; activated carbon in the main-layer to mainly adsorb methane, and LiLSX zeolite in the top-layer to remove trace nitrogen which had eluted from the earlier layers, for obtaining pure hydrogen product. High purity hydrogen product (>99%) with high recovery (>85%) was achieved with the PSA system for different hydrogen concentrations (5–30%) in the 30 bar feed stream. We also compared the PSA system against an electrolyzer generating hydrogen onsite. Our analysis suggests that the PSA competes favorably, even at a low hydrogen recovery of 40% in cases where the PSA plant is built at a pressure reduction station.

Phycoremediation of aquaculture wastewater and algal lipid extraction for fuel conversion

In this review, it is discussed the prominent effect generated from aquaculture wastewater considered as the major water polluting crisis in the entire world. The cause rose due to intense development and improvement in aquaculture by the aquatic habitat species triggering quite a challenge in the environment. Scrutinizing this problem, researchers have found a way to tackle it by cultivating algal species in aquaculture wastewater in order to remove its high content of organic and inorganic pollutants. The theory proves wastewater serves as a nutrient source for algal growth and development such as phosphorous, nitrogen, and other trace elements. Besides harvesting the algal biomass from aquaculture wastewater, the extraction of lipid is also processed for biofuel production. Hence, the discussion includes conversion of wastewater into organic and inorganic pollutant-free water with low cost-effective method via algal cultivation in wastewater and high lipid yield for biofuel with a carbon-free and sustainable environment.

Plantation tree growth responses to P, N, K and minor and trace elements on low fertility savanna soils

Context Widespread soil nutrient limitations in savanna soils typically constrain plantation tree growth, and hence limit economic opportunities in tropical regions. Fertilisation offers an approach to overcome soil nutrient limitations, but requires research on nutrient contents and rates to maximise plant growth while avoiding nutrient imbalances that have stunted plant growth under some fertiliser regimes. Aims To test the hypothesis that multiple nutrient limitations exist in savanna soils, with nutrient deficiencies exposed in sequence with fertiliser addition. Methods Factorial field experiments tested the growth of the plantation timber species African mahogany (Khaya senegalensis) to applications of phosphorus, potassium, nitrogen and minor and trace elements (referred to as the T treatment) on a kandosol soil near Darwin, Australia. Key results Under high stocking rates to induce deficiencies sooner through utilisation of a high proportion of the available nutrient capital, positive responses and interactions to all four main treatments were recorded. There were step-wise responses to phosphorus, potassium, nitrogen and the T treatment. Treatments with greater mean tree growth were more uniform than lesser-growing treatments, even though the largest and smallest individuals were similar across treatments. Conclusions Consistent with our hypothesis, correcting one soil nutrient deficiency exposed another in sequence as nutrient reserves were depleted in a drying soil. Variation in tree performance across plots indicates that testing of soil nutrients and fertiliser responses need to be assessed in replicate and dispersed samples. Implications Khaya senegalensis demonstrated potential for plantation use in northern Australia with minimal mortality from termites and other causes, if supported with broad-spectrum fertilisation balanced to match plant growth and water availability.

NEW INDICATORS OF SOIL FERTILITY

Soil fertility is the main issue in agriculture. The well-being of the people receiving food and technical raw materials for the processing industry depends on it. Knowledge of soil fertility allows us to develop forecasts of crop yields for the future, as well as plan targeted measures to increase fertility and ensure its sustainability. (Research purpose) The research purpose is increasing the efficiency of the production and application of organic fertilizers, reducing the environmental burden and saving the components. (Materials and methods) Microbiological, agrochemical, lysimetric and field studies were used to determine the effectiveness of organic fertilizers. (Results and discussion) The article presents the new organic fertilizer - a soil-biological complex that simultaneously possesses the properties of organic fertilizer, herbicide and fungicide. (Conclusions) The doses of the introduction of a soil-biological complex for the full nutrition of various agricultural crops were described taking into account the regularities of the influence of the microbiological community on the soil, cultivated crops and the conditions of their growth. The article described the influence of the soil-biological complex on agronomic indicators (lumpiness, moisture capacity, air permeability, stickiness, resistance to waterlogging and drought); agrochemical indicators (nitrogen, phosphorus, potassium and other trace elements, organic matter, C:N ratio); resistance of plants to diseases; reduction of soil contamination; improvement of product quality; reduction of vegetation periods; interaction of various types of microorganisms, especially in the rhizosphere zone - the root zone of the soil. It is necessary to introduce an assessment of the quality of organic fertilizers as a mandatory indicator of the composition of the microbiological community, which will allow predicting the system of fertilization and care of crops. Specialists need to be trained in a new approach to the production and use of organic fertilizers.

Nanoarchitectonics of three-dimensional ZnO–BiVO4 for trace nitrogen dioxide gas detection

In the present study, several novel three-dimensional (3D) ZnO–BiVO4 composites were prepared using the hydrothermal method, and their ability to detect nitrogen dioxide (NO2) gas was assessed. The fabricated sensing materials were examined using X-ray diffraction, transmission electron microscopy, energy dispersive spectrometry, scanning electron microscopy, ultraviolet–visible spectrophotometry, X-ray photoelectron spectroscopy, and surface-area and porosity analysis. The sensing material assessments verified that 3D ZnO–BiVO4 was successfully prepared; the sensing data revealed that 3D ZnO–BiVO4 exhibited excellent sensing response (24.6) to 1-ppm NO2 at room temperature. The composites exhibited a fast response (28 s) and short recovery time (75 s) when detecting 1-ppm NO2; they also exhibited long-term stability (decline of approximately 7% after 30 days) and selectivity to 10-ppm NO2 gas. A reasonable NO2 gas sensing mechanism for 3D ZnO–BiVO4 heterojunction was also proposed in this paper.

Trehalose: A mycogenic cell wall elicitor elicit resistance against leaf spot disease of broccoli and acts as a plant growth regulator

Elicitors are biochemicals, and the cell wall-derived elicitors from fungi can trigger defence mechanisms in plants by increasing the phytoalexin accumulation when they encounter the pathogens. The main objective of this research was to purify and characterize a cell wall elicitor from Trichoderma atroviride (TaCWE) and evaluate the seed priming effect of that elicitor for inducing systemic resistance in broccoli plants against leaf spot disease. Amongst the tested TaCWE concentrations of the seed priming (5, 10, & 25 mg ml−1), 10.0 mg ml−1 showed significantly (P < 0.05) improved early emergence, the rate of germination at 94%, and observed seedling vigour of 2601. Also, elicitor (10 mg ml−1) treatment alone induced 57% plant protection. On the contrary, the elicitor treated and pathogen inoculated plants induced a notable 72% protection against leaf spot disease of broccoli caused by A. brassicicola. Thus, the primed seeds with elicitor showed induced disease resistance and plant growth promotion. The prominent molecule present in the purified extracted cell wall elicitor is confirmed as trehalose. The AFM analysis indicated the trehalose length and width as 10.16 µm and 2.148 µm, respectively. FTIR chromatogram further confirmed trehalose in abundance with traces of carbon, hydrogen, nitrogen, oxygen, and LC-MS profile with a single peak eluted with a retention time of 3.78 min. The findings of this study contribute to understanding better the role of trehalose, a biogenic cell-wall elicitor that can induce systemic resistance against leaf spot disease and regulate plant growth in the broccoli plants.

Enhanced Volatile Fatty Acid Production from Oil Palm Empty Fruit Bunch through Acidogenic Fermentation—A Novel Resource Recovery Strategy for Oil Palm Empty Fruit Bunch

The glucan-rich fraction, hemicellulosic compounds-rich fraction, and a mixture of both fractions obtained from organosolv pretreatment of oil palm empty fruit bunch (OPEFB) were used as substrates to produce volatile fatty acids (VFAs) in acidogenic fermentation. In this study, the effects of medium adjustment (carbon to nitrogen ratio and trace elements supplementation) and methanogenesis inhibition (through the addition of 2-bromoethanesulfonate or by heat shock) to enhance VFAs yield were investigated. The highest VFA yield was 0.50 ± 0.00 g VFAs/g volatile solid (VS), which was obtained when methanogens were inhibited by heat shock and cultivated in a mixture of glucan-rich and hemicellulosic compounds-rich fractions. Under these conditions, the fermentation produced acetic acid as the only VFA. Based on the results, the mass balance of the whole process (from pretreatment and fermentation) showed the possibility to obtain 30.4 kg acetic acid and 20.3 kg lignin with a 70% purity from 100 kg OPEFB.

Catkin-derived mesoporous carbon-supported molybdenum disulfide and nickel hydroxyl oxide hybrid as a bifunctional electrocatalyst for driving overall water splitting

In this work, a two-dimensional heterostructure of molybdenum disulfide (MoS2) and nickelhydroxyloxide (NiOOH) nanosheets supported on catkin-derived mesoporous carbon (C-MC) was constructed and exploited as an efficient electrocatalyst for overall water splitting. The C-MC nanostructure was prepared by pyrolyzing biomass material of catkin at 600 °C in N2 atmosphere. The C-MC network exhibited hollow nanotube structure and had a large specific surface area, comprising trace nitrogen and a large amount of oxygen vacancies. It further served as the support for the growth of NiOOH nanosheets (NiOOH@C-MC), which was combined with MoS2 nanosheets by in situ growth, yielding a multicomponent electrocatalyst (MoS2@NiOOH@C-MC). By integrating the superior hydrogen evolution reaction (HER) performance of MoS2, oxygen evolution reaction (OER) performance of NiOOH, and the fast electron transfer capability of C-MC, the prepared MoS2@NiOOH@C-MC illustrated a low potential of − 250 mV for HER and 1.51 V for OER at the current density of 10 mV cm−2. Consequently, when applied as the working electrode for driving overall water splitting in a two-electrode system, the bifunctional MoS2@NiOOH@C-MC electrocatalyst displayed a low cell voltage of 1.62 V at the current density of 10 mA cm−2. The present work provides a new strategy that uses biomass material for developing bifunctional electrocatalyst for overall water splitting.

Enhanced polyhydroxybutyrate production from acid whey through determination of process and metabolic limiting factors

To sustainably produce biodegradable polyhydroxybutyrate (PHB), this study investigated effects of process and metabolic limiting factors during bioconversion of acid whey (AW) to PHB, offering economic and environmental advantages for dairy industry. Recombinant Escherichia coli LSBJ was used to achieve high PHB yields by utilizing both lactose and lactic acid as carbon source. Up to 85% PHB accumulation was achieved during growth on the synthetic AW. Growth on raw AW had the highest PHB yield of 4 g/L and a high substrate utilization efficiency (95%). Notably, ratios of lactate: lactose and C/N impacted metabolic flux and PHB yields. Maintaining the fermentation pH enhanced PHB production. Furthermore, additives of inorganic nitrogen sources, minerals and trace metals promoted PHB production from AW. The study improves the understanding of factors affecting utilization of AW and demonstrated the high PHB yields using recombinant E. coli that could be leveraged to design a sustainable process.

Tracking nitrate sources in agricultural-urban watershed using dual stable isotope and Bayesian mixing model approach: Considering N transformation by Lagrangian sampling

A dual isotopes approach and the Bayesian isotope mixing model were applied to trace nitrogen pollution sources and to quantify their relative contribution to river water quality. We focused on two points to enhance the applicability of the method: 1) Direct measurement on the end-members to distinguish “sewage” and “manure” which used to be grouped in one pollution source as their isotope ranges overlap; 2) The Lagrangian sampling method was applied to consider the transport of nitrogen pollutants in a long river so that any fractionation process can be dealt with in the given Bayesian modeling framework. The results of the analysis confirmed the NO3− isotope composition in the river of interest to be within the range of NO3− with origins in “NH4+ in fertilizer”, “Soil N”, and “Manure and sewage” pollution. This suggests that nitrogen pollution is mostly attributed to anthropogenic sources. The δ18O NO3 value follows the range +2.5∼+15.0‰, implying that NO3− in the river is mainly derived from nitrification, and possible nitrification in groundwater or waterfront other than surface water. The ratio of the concentration of δ15N NO3 to that of δ18O NO3, and the corresponding regression equation indicates that the denitrification effect in surface water was insignificant during the study period. From the results of the contribution ratio of each source, improving the water quality of the discharge from the sewage treatment plants was proved to be the key factor to reduce nitrogen pollution in the river.

Variability of quantitative traits in winter triticale in the central region of Belarus

Introduction: The article presents the results of a long-term study of quantitative traits in winter triticale varieties and accessions grown in the soil/climatic conditions of the central region of Belarus using conventional and intensive cultivation technologies. The effects of the intensification level on the yield, performance constituents and triticale grain quality are described.&#x0D; Purpose: to assess the variability of quantitative traits in winter triticale grown by conventional and intensive cultivation technologies in Belarus.&#x0D; Material and methods: Winter hexaploid triticale varieties and promising accessions grown by traditional and intensive technologies in a competitive variety trial nursery were studied. The plot area was 10 m2; the replication number was three; the design was randomized; the seeding rate was 4.5 million viable seeds per hectare; the observation period was in 2011-2020. Upon intensive cultivation, additional doses of nitrogen fertilizers, trace elements (Cu, Mn), growth regulators and fungicides were applied. The contents of crude protein, gluten and starch in grain were determined by near-infrared spectroscopy&#x0D; Results and discussion: During the observation period, the average yield from the winter triticale accessions in the competitive variety trial nursery was on 69.3 dt/ha and 77.8 dt/ha upon the application of traditional and intensive cultivation technologies, respectively. The additional factors of intensification increased the yield by 8.5 dt/ha or by 12.3 %. The constituents of the main spike performance as well as contents of crude protein and gluten in winter triticale grain also grew. Strengthening of intensification of the cultivation technology didn’t significantly affect the test weight, 1000-grain weight or crude protein content.&#x0D; Conclusions. The use of additional methods of intensification was demonstrated to change the absolute values of the winter triticale indicators, to have no key impact on the level of their environmental of genotypic variability. The test weight and crude protein content were the most stable traits, while the gluten content and yield – the least stable ones, as their values were determined by both varietal specificity and environmental factors

Production of spiculisporic acid by Talaromyces trachyspermus in fed-batch bioreactor culture

Spiculisporic acid (SA) is a fatty acid-type biosurfactant with one lactone ring and two carboxyl groups. It has been used in metal removers and cosmetics, because of its low propensity to cause irritation to the skin, its anti-bacterial properties, and high surface activity. In the present study, we report an effective method for producing SA by selecting a high-producing strain and investigating the effective medium components, conditions, and environments for its culture. Among the 11 kinds of Talaromyces species, T. trachyspermus NBRC 32238 showed the highest production of a crystalline substance, which was determined to be SA using NMR. The strain was able to produce SA under acidic conditions from hexoses, pentoses, and disaccharides, with glucose and sucrose serving as the most appropriate substrates. Investigation of nitrogen sources and trace metal ions revealed meat extract and FeCl3 as components that promoted SA production. Upon comparing the two types of cultures with glucose in a baffle flask or aeration bioreactor, SA production was found to be slightly higher in the flask than in the reactor. In the bioreactor culture, sucrose was found to be an appropriate substrate for SA production, as compared to glucose, because with sucrose, the lag time until the start of SA production was shortened. Finally, fed-batch culture with sucrose resulted in 60 g/L of SA, with a total yield of 0.22 g SA/g sucrose and a productivity of 6.6 g/L/day.

MoS2 Nanoflowers Decorated with Au Nanoparticles for Visible-Light-Enhanced Gas Sensing

Highly sensitive and selective detection of trace nitrogen dioxide (NO2) in a complex outdoor air environment is an urgent need to guarantee human health and a beautiful environment. The effective combination of heterostructure and light irradiation is an important strategy to achieve high-performances gas sensors. However, the effect of light irradiation on gas-sensitive properties of heterostructure materials is not yet clear, and it is urgent to clarify the relationship between light irradiation and heterostructure for gas-sensing materials. Herein, a 530 nm-light-assisted Au–MoS2 gas sensor with a low detection limit as well as robust antihumidity interference ability is developed through introducing the localized surface plasmon resonance (LSPR) effect of Au nanoparticles (NPs). Under 530 nm light illumination, a Au–MoS2 gas sensor can achieve limit detection of NO2 as low as 10 ppb without operating temperature along with robust antihumidity ability. The optical simulation and experimental results show that the modification of MoS2 by Au NPs (diameter: 30 nm) combined with the matching light-assisted (530 nm) gas detection mode can make MoS2 fully absorb visible light and effectively improve the extinction cross section by taking full advantage of the LSPR effect, which is the primary reason for the enhanced performances of a MoS2-based gas sensor. This work provides theoretical and experimental guidance for gas sensors to effectively enhance the ability of gas detection by means of the light-assisted mode at room temperature, which opens up a unique approach to design high-performance gas sensors for trace-level gas detection.

Catalytic activation preparation of nitrogen-doped hierarchical porous bio-char for efficient adsorption of dichloromethane and toluene

Volatile organic compounds (VOCs) adsorption by carbonaceous materials is one of the most promising technologies for their efficient abatement, which requires the construction of both suitable porous structures and functional groups. In this work, nitrogen-doped hierarchical porous bio-char (NHWC) was prepared via a facile catalytic activation process, in which NH3·H2O was used as activation agent to introduce nitrogen dopants and trace CaCl2 acted as catalyst for hierarchical pore formation. VOCs dynamic adsorption experiments indicated that the prepared NHWC exhibits excellent dichloromethane and toluene adsorption properties. Particularly, the combined adsorption capacities of dichloromethane and toluene in NHWC are 54.9 and 308 mg g−1, respectively, much higher than those in microporous bio-char, indicating the significant role of hierarchical porosity in multiple VOCs molecules combined adsorption. Control experiments using the prepared model carbon materials indicate that the excellent combined adsorption performance originates from both nitrogen dopants and hierarchical porous structure. Density functional theory calculations further reveal that the introduced nitrogen functional groups enhance the van der Waals interactions between VOCs molecules and carbon surface, thereby improving the combined adsorption of VOCs. This work provides a new strategy of optimizing the pore structure and surface chemistry of bio-char.