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2D organic crystals play a unique role in photodetection owing to their tunable detection wavelength, low manufacturing cost, compatibility with lightweight, and controllable synthesis. However, their detection wavelength range mainly encompasses the visible (Vis) and near‐infrared (NIR) spectra. Herein, 2D erucamide crystals are synthesized using nitrogen gas and methanol as raw materials without catalysts at room temperature under atmospheric pressure via laser processing. The synthesized 2D erucamide is demonstrated to be a promising broad bandgap organic semiconductor material. A UV photodetector made of 2D erucamide exhibited a responsivity as high as 145 mA W−1, a millisecond‐level response speed, and an excellent detectivity of 4.96 × 109 Jones. Furthermore, the synthesized erucamide showed an excellent UV–vis suppression ratio (R254 nm/R532 nm) of 59. The synthesis mechanism of erucamide via laser bubbling in liquids is proposed. Thermodynamically, the high temperature of the bubbles is beneficial for nitrogen and methanol decomposition. Kinetically, rapid bubble quenching facilitates final product formation. This accomplishment represented the pioneering utilization of lasers in converting nitrogen gas into organic compounds while introducing 2D erucamide into the realm of organic UV photodetectors. [ABSTRACT FROM AUTHOR]

The electrochemical reduction of CO2 into value-added chemicals has been explored as a promising solution to realize carbon neutrality and inhibit global warming. This involves utilizing the electrochemical CO2 reduction reaction (CO2RR) to produce a variety of single-carbon (C1) and multi-carbon (C2+) products. Additionally, the electrolyte solution in the CO2RR system can be enriched with nitrogen sources (such as NO3−, NO2−, N2, or NO) to enable the synthesis of organonitrogen compounds via C–N coupling reactions. However, the electrochemical conversion of CO2 into valuable chemicals still faces challenges in terms of low product yield, poor faradaic efficiency (FE), and unclear understanding of the reaction mechanism. This review summarizes the promising strategies aimed at achieving selective production of diverse carbon-containing products, including CO, formate, hydrocarbons, alcohols, and organonitrogen compounds. These approaches involve the rational design of electrocatalysts and the construction of coupled electrocatalytic reaction systems. Moreover, this review presents the underlying reaction mechanisms, identifies the existing challenges, and highlights the prospects of the electrosynthesis processes. The aim is to offer valuable insights and guidance for future research on the electrocatalytic conversion of CO2 into carbon-containing products of enhanced value-added potential. [ABSTRACT FROM AUTHOR]

The COVID‐19 pandemic perturbed air pollutant emissions as cities shut down worldwide. Peroxyacyl nitrates (PANs) are important tracers of photochemistry that are formed through the oxidation of non‐methane volatile organic compounds in the presence of nitrogen oxide radicals (NOx = NO + NO2). We use satellite measurements of free tropospheric PANs from the Suomi‐National Polar‐orbiting Partnership Cross‐track Infrared Sounder (CrIS) over eight of the world's megacities. We quantify the seasonal cycle of PANs over these megacities and find seasonal maxima in PANs correspond to seasonal peaks in local photochemistry. CrIS is used to explore changes in PANs in response to the COVID‐19 lockdowns. Statistically significant changes to PANs occurred over four megacities: with decreases over Los Angeles and Delhi, and increases over Mexico City and Beijing in the winter. Our analysis suggests that large perturbations in NOx may not result in significant declines in NOx export potential of megacities. Plain Language Summary: The COVID‐19 pandemic led to the lockdown of urban centers worldwide, drastically perturbing the concentrations of global air pollutants. Peroxyacyl nitrates (PANs) are important photochemical pollutants formed from reactions between NOx and volatile organic compounds, which were substantially reduced during the pandemic. We use satellite measurements of PANs from the Suomi‐National Polar‐orbiting Partnership Cross‐track Infrared Sounder in the free troposphere over and surrounding eight of the world's megacities. Seasonal cycles of PANs are pronounced and the seasonal maxima correspond to seasonal peaks in local photochemistry. Significant changes to PANs in response to COVID‐19 occurred over four out of the eight cities: PANs decreased over Los Angeles and Delhi, and PANs increased over Mexico City and Beijing in the winter. Our results indicate that large changes in NOx may not result in equally significant changes to PANs and the NOx export potential of megacities. Key Points: There are pronounced seasonal cycles of peroxyacyl nitrates (PANs) over each megacity that align with seasonal maximums in photochemistryObserved free tropospheric mixing ratios of PANs during COVID‐19 were significantly different over four out of eight surveyed megacitiesSensitivity of free tropospheric PANs to the abundance of precursors is seasonally dependent in some locations [ABSTRACT FROM AUTHOR]

Tropospheric ozone is an air pollutant and a greenhouse gas whose anthropogenic production is limited principally by the supply of nitrogen oxides (NOx) from combustion. Tropospheric ozone in the northern hemisphere has been rising despite the flattening of NOx emissions in recent decades. Here we propose that this sustained increase could result from the photolysis of nitrate particles (pNO3−) to regenerate NOx. Including pNO3− photolysis in the GEOS‐Chem atmospheric chemistry model improves the consistency with ozone observations. Our simulations show that pNO3− concentrations have increased since the 1960s because of rising ammonia and falling SO2 emissions, augmenting the increase in ozone in the northern extratropics by about 50% to better match the observed ozone trend. pNO3− will likely continue to increase through 2050, which would drive a continued increase in ozone even as NOx emissions decrease. More work is needed to better understand the mechanism and rates of pNO3− photolysis. Plain Language Summary: In the troposphere, ozone is an air pollutant and a greenhouse gas. Tropospheric ozone forms from reactions involving carbon monoxide and volatile organic compounds in the presence of nitrogen oxides. Global emissions of nitrogen oxides have been leveling off in the past few decades, yet tropospheric ozone levels have kept on rising. We propose that this rise in ozone could be driven by a growing source of nitrogen oxides from the photolysis of nitrate particles, which have become more abundant due to falling sulfur dioxide and rising ammonia emissions. We find that including nitrate particle photolysis in an atmospheric chemistry model improves its consistency with the observed ozone distribution and trends. Our results point to the importance of considering nitrate particle photolysis for future projections of climate forcing from tropospheric ozone, and the need for further work to reduce the uncertainty in the mechanism and rates of the process. Key Points: Particulate nitrate photolysis improves the consistency of tropospheric ozone in the GEOS‐Chem model with observationsIncrease in particulate nitrate due to falling SO2 and rising NH3 emissions could augment the long‐term increase in tropospheric ozoneBetter characterization of the mechanism and rates of particulate nitrate photolysis is needed [ABSTRACT FROM AUTHOR]

This Review presents the electrochemical "waste-to-valuables" concept by discussing its practicability in terms of the waste removal efficiency, valuable production efficiency, downstream valuable recovery, applications, and economic appraisal. Specifically, the electrocatalytic upgrading of nitrogenous wastes, i.e., NO and NO 3 − as representative air and aqueous pollutants, respectively, into high-value-added chemicals, i.e., NH 3 via NO/NO 3 − reduction and urea/amide/amine via N-integrated CO 2 reduction is focused. [Display omitted] • The electrochemical upgrading of nitrogenous wastes into value-added products represents a sustainable approach for achieving "waste-to-valuables" conversion. • Design strategies for catalyst, electrolyte, and reactor have been developed to facilitate the electrochemical conversion of nitric oxide/nitrate, both at low and high concentrations, into ammonia. • Nitric oxide/nitrite/nitrate-integrated carbon dioxide reduction unlocks organonitrogen compounds via the electrochemical formation of C−Nbond. In response to the ever-increasing global population and the growing demand for energy and food, human activities have exerted a substantial impact on the global nitrogen cycles. In this context, the electrocatalytic upgrading of nitrogenous wastes into high-value chemicals under ambient conditions, ideally powered by renewable electricity, emerges as a promising approach to concurrently manage nitrogen-containing wastes and facilitate sustainable production of valuable chemicals. This review presents the electrochemical "waste-to-valuables" concept by discussing its practicality in terms of waste removal efficiency, valuable production efficiency, downstream recovery of valuables, potential applications, and economic feasibility. Specifically, the electrocatalytic upgrading of nitrogenous wastes, i.e., nitric oxide and nitrate as representative air and aqueous pollutants, respectively, into high-value-added chemicals, i.e., ammonia via nitric oxide/nitrate reduction and urea/amide/amine via nitrogen-integrated carbon dioxide reduction is focused. Targeting nitrogenous waste exhausts/streams with low/high concentrations, reactor design and catalyst design principles are reviewed with representative examples. Finally, the major challenges and opportunities associated with the practical applications of the "waste-to-valuables" concept are discussed. [ABSTRACT FROM AUTHOR]

Organonitrogen compounds are of vital importance to our lives. For almost all organonitrogen compounds, ammonia is only the feedstock as a nitrogen source. Ammonia is produced from dinitrogen (N2) and dihydrogen (H2) by the Haber‐Bosch process, which consumes an enormous amount of energy. As an alternative method to convert N2 into organonitrogen compounds under milder conditions, various stoichiometric reactions with transition metal complexes have been explored for the last 50 years. However, the field of catalytic formation of organonitrogen compounds directly from N2 with transition metal complexes is still in its infancy. This short review summarizes strategies to achieve the direct synthesis of organonitrogen compounds from N2 under mild reaction conditions using transition metal complexes ranging from stoichiometric reactions to catalytic reactions. [ABSTRACT FROM AUTHOR]

Colletotrichum siamense is a hemibiotrophic ascomycetous fungus responsible for mango anthracnose. The key genes involved in C. siamense infection remained largely unknown. In this study, we conducted weighted gene co-expression network analysis (WGCNA) of RNA-seq data to mine key genes involved in Colletotrichum siamense-mango interactions. Gene modules of Turquoise and Salmon, containing 1039 and 139 respectively, were associated with C. siamense infection, which were conducted for further analysis. GO enrichment analysis revealed that protein synthesis, organonitrogen compound biosynthetic and metabolic process, and endoplasmic reticulum-related genes were associated with C. siamense infection. A total of 568 proteins had homologs in the PHI database, 370 of which were related to virulence. The hub genes in each module were identified, which were annotated as O-methyltransferase (Salmon) and Clock-controlled protein 6 (Turquoise). A total of 24 proteins exhibited characteristics of SCRPs. By using transient expression in Nicotiana benthamiana, the SCRPs of XM_036637681.1 could inhibit programmed cell death (PCD) that induced by BAX (BCL-2-associated X protein), suggesting that it may play important roles in C. siamense infection. A mango-C. siamense co-expression network was constructed, and the mango gene of XM_044632979.1 (auxin-induced protein 15A-like) was positively associated with 5 SCRPs. These findings help to deepen the current understanding of necrotrophic stage in C. siamense infection. [ABSTRACT FROM AUTHOR]

This study investigated a feasible model for treating actual shrimp farm wastewater at a pilot scale that could be applied to farms in the Mekong Delta area. The research was carried out using a hybrid constructed wetlands (HCWs) model, which included a floating constructed wetland (FCW, total area of 1,500 m2) and a horizontal sub-surface constructed wetland (HSCW, total area of 400 m2). The HCWs were cultivated with native plants including: Scirpus littoralis Schrab, Cyperus alternifolius, and Paspalum vaginatum. These plants are all adapted to the high salinity levels of shrimp farm wastewater. The system was operated for 30 days to treat shrimp farm effluent. Results indicated that the model effectively removed organic matter and nitrogen compounds from the wastewater. The treated wastewater had low concentrations of COD (10.0-15.4 mg/L), BOD5 (7.1-12.5 mg/L), NH4 + -N (0.04-1.11 mg/L), and TN (0.17-1.83 mg/L), which met the reliable conditions for reuse or safety requirements for discharge to aquatic systems. The findings of this study have significant implications for the sustainable management of shrimp farm wastewater in the Mekong Delta area. The HCWs model is a feasible and effective way to treat this type of wastewater, and it could be adapted to other regions facing similar challenges. [ABSTRACT FROM AUTHOR]

Plants uptake and assimilate nitrogen from the soil in the form of nitrate, ammonium ions, and available amino acids from organic sources. Plant nitrate and ammonium transporters are responsible for nitrate and ammonium translocation from the soil into the roots. The unique structure of these transporters determines the specificity of each transporter, and structural analyses reveal the mechanisms by which these transporters function. Following absorption, the nitrogen metabolism pathway incorporates the nitrogen into organic compounds via glutamine synthetase and glutamate synthase that convert ammonium ions into glutamine and glutamate. Different isoforms of glutamine synthetase and glutamate synthase exist, enabling plants to fine-tune nitrogen metabolism based on environmental cues. Under stressful conditions, nitric oxide has been found to enhance plant survival under drought stress. Furthermore, the interaction between salinity stress and nitrogen availability in plants has been studied, with nitric oxide identified as a potential mediator of responses to salt stress. Conversely, excessive use of nitrate fertilizers can lead to health and environmental issues. Therefore, alternative strategies, such as establishing nitrogen fixation in plants through diazotrophic microbiota, have been explored to reduce reliance on synthetic fertilizers. Ultimately, genomics can identify new genes related to nitrogen fixation, which could be harnessed to improve plant productivity. [ABSTRACT FROM AUTHOR]

The histone‐like protein HU plays a diverse role in bacterial physiology from the maintenance of chromosome structure to the regulation of gene transcription. HU binds DNA in a sequence‐non‐specific manner via two distinct binding modes: (i) random binding to any DNA through ionic bonds between surface‐exposed lysine residues (K3, K18, and K83) and phosphate backbone (non‐specific); (ii) preferential binding to contorted DNA of given structures containing a pair of kinks (structure‐specific) through conserved proline residues (P63) that induce and/or stabilize the kinks. First, we show here that the P63‐mediated structure‐specific binding also requires the three lysine residues, which are needed for a non‐specific binding. Second, we demonstrate that substituting P63 to alanine in HU had no impact on non‐specific binding but caused differential transcription of diverse genes previously shown to be regulated by HU, such as those associated with the organonitrogen compound biosynthetic process, galactose metabolism, ribosome biogenesis, and cell adhesion. The structure‐specific binding also helps create DNA supercoiling, which, in turn, may influence directly or indirectly the transcription of other genes. Our previous and current studies show that non‐specific and structure‐specific HU binding appear to have separate functions‐ nucleoid architecture and transcription regulation‐ which may be true in other DNA‐binding proteins. [ABSTRACT FROM AUTHOR]

Electrochemical C–N coupling reactions based on abundant small molecules (such as CO2 and N2) have attracted increasing attention as a new "green synthetic strategy" for the synthesis of organonitrogen compounds, which have been widely used in organic synthesis, materials chemistry, and biochemistry. The traditional technology employed for the synthesis of organonitrogen compounds containing C–N bonds often requires the addition of metal reagents or oxidants under harsh conditions with high energy consumption and environmental concerns. By contrast, electrosynthesis avoids the use of other reducing agents or oxidants by utilizing "electrons", which are the cleanest "reagent" and can reduce the generation of by-products, consistent with the atomic economy and green chemistry. In this study, we present a comprehensive review on the electrosynthesis of high value-added organonitrogens from the abundant CO2 and nitrogenous small molecules (N2, NO, NO2−, NO3−, NH3, etc.) via the C–N coupling reaction. The associated fundamental concepts, theoretical models, emerging electrocatalysts, and value-added target products, together with the current challenges and future opportunities are discussed. This critical review will greatly increase the understanding of electrochemical C–N coupling reactions, and thus attract research interest in the fixation of carbon and nitrogen. [ABSTRACT FROM AUTHOR]

Simple Summary: To understand the molecular mechanism of the cocoon silk evolution of silkworms, we systematically compared the silk gland transcriptomes among the wild, early domestic, and improved silkworms and indicated that modern breeding in silkworms brought drastic expressional changes of genes compared with early domestication. Improved silkworms demonstrated repressed basic nitrogen synthesis metabolism, whereas they had enhanced dynamics of protein post-translation modification. In addition, we highlighted one candidate improvement gene up-regulated in the silk glands of the improved silkworms that is involved in the function of the nervous system. Early domestication and the following improvement are two important processes in the cocoon silk evolution of silkworms. In contrast to early domestication, understanding of the improvement process is still fuzzy. By systematically comparing the larval silk gland transcriptomes of the wild, early domestic, and improved silkworms, we highlighted a novel landscape of transcriptome in the silk glands of improved ones. We first clarified that silk cocoon protein genes were up-regulated in modern breeding but not in early domestication. Furthermore, we found that differentially expressed genes (DEGs) between improved and early domestic silkworms (2711), as well as between improved and wild silkworms (2264), were obviously more than those between the early domestic and wild silkworms (158), with 1671 DEGs specific in the improved silkworm (IS-DEGs). Hierarchical clustering of all the DEGs consistently indicated that improved silkworms were significantly diverged from the early domestic and wild silkworms, suggesting that modern breeding might cause prompt and drastic dynamic changes of gene expression in the silk gland. We further paid attention to these 1671 IS-DEGs and were surprised to find that down-regulated genes were enriched in basic organonitrogen compound biosynthesis, RNA biosynthesis, and ribosome biogenesis processes, which are generally universally expressed, whereas those up-regulated genes were enriched in organonitrogen compound catabolic processes and functions involving in the dynamic regulation of protein post-translation of modification. We finally highlighted one candidate improvement gene among these up-regulated IS-DEGs, i.e., GDAP2, which may play roles in silk behavior and the overall robustness of the improved silkworm. The findings strongly suggest that modern breeding may facilitate effective control of the basic consumption of nitrogen and a stronger switch of nitrogen resources from other tissues to the silk glands, for an efficient supply for silk production, and implies the importance of brain behavior and robustness in silk yield improvement of modern breeding. [ABSTRACT FROM AUTHOR]

The scalable and durable electrosynthesis of high‐valued organonitrogen compounds from carbon‐ and nitrogen‐containing small molecules, especially operating at a high current density, is highly desirable. Here, a one‐pot electrooxidation method to synthesize formamide (HCONH2) from methanol and ammonia over a commercial boron‐doped diamond (BDD) catalyst is reported. The formamide selectivity from methanol and formamide Faradaic efficiency (FEHCONH2 ${{_{{\rm HCONH}{_{2}}}}}$) achieve 73.2 % and 41.2 % at the current density of 120 mA cm−2 with high durability. The C−N bond originates from the nucleophilic attack of ammonia on an aldehyde‐like intermediate. Impressively, an 8 L electrolyzer is employed for the pilot plant test over a 2200 cm2 BDD electrode, which exhibits 33.5 % FEHCONH2 ${{_{{\rm HCONH}{_{2}}}}}$ at 120 mA cm−2 (current: 264 A) with a yield rate of 36.9 g h−1, demonstrating the potential of this technique for large‐scale electrosynthesis of formamide. [ABSTRACT FROM AUTHOR]

The scalable and durable electrosynthesis of high‐valued organonitrogen compounds from carbon‐ and nitrogen‐containing small molecules, especially operating at a high current density, is highly desirable. Here, a one‐pot electrooxidation method to synthesize formamide (HCONH2) from methanol and ammonia over a commercial boron‐doped diamond (BDD) catalyst is reported. The formamide selectivity from methanol and formamide Faradaic efficiency (FEHCONH2 ${{_{{\rm HCONH}{_{2}}}}}$) achieve 73.2 % and 41.2 % at the current density of 120 mA cm−2 with high durability. The C−N bond originates from the nucleophilic attack of ammonia on an aldehyde‐like intermediate. Impressively, an 8 L electrolyzer is employed for the pilot plant test over a 2200 cm2 BDD electrode, which exhibits 33.5 % FEHCONH2 ${{_{{\rm HCONH}{_{2}}}}}$ at 120 mA cm−2 (current: 264 A) with a yield rate of 36.9 g h−1, demonstrating the potential of this technique for large‐scale electrosynthesis of formamide. [ABSTRACT FROM AUTHOR]

Azo compounds are widely used in polymerization as an initiator for chain polymerization reactions. Although they have excellent initiating properties, the thermal instability and associated risk of ignition and explosion cannot be ignored. This paper aimed to decode the thermal behavior and evaluation thermal hazards of two water-soluble azo initiators 2,2′-azobis(2-methylpropionamidine) dihydrochloride (AIBA) and 2,2′-azobis(2-(2-imidazoline-2-yl) propane) dihydrochloride (AIBI). Thermogravimetric analysis and adiabatic experiments were used to investigate the decomposition process of these two azos under atmospheric and adiabatic conditions. The apparent activation energy (Ea) and time to maximum rate under adiabatic conditions (TMRad) were obtained based on above experiments. Decomposition products and mechanisms of AIBA and AIBI were preliminarily studied using a thermogravimetric analyzer coupled with Fourier transform infrared spectrometer system. Results showed that most decomposition products of AIBA and AIBI still existed in the form of organic compounds under nitrogen conditions. Furthermore, the leakage of pyrolysis gas (such as ammonia) should be prevented from causing environmental pollution. [ABSTRACT FROM AUTHOR]

The sample containing 57 volatile organic compounds (VOCs) in nitrogen at a nominal 1 ppmv was prepared in our lab using weighting method. A methodology for determination of the 57 VOCs using a two-dimensional gas chromatography equipped with Deans switches and two flame ionization detectors (GC × GC–FID) was developed and validated for resolution, asymmetry, sensitivity, precision (intra-day precision and inter-day precision), linearity, limit of detection (LOD), limit of quantification (LOQ) and accuracy. In this study, resolution, asymmetry and sensitivity of the analytical method were improved，intra-day precisions of all the compounds were <1% and inter-day precisions were between 0.9 and 3.0%. In addition, LOQ and LOD were in the range of 0.024–0.185 ppmv and 0.012–0.092 ppmv, respectively. An excellent linearity was obtained (R 2 > 0.9995). At the meantime, the accuracy of the analytical method was evaluated by determining the concentration of a certified reference material. [ABSTRACT FROM AUTHOR]

There is growing evidence that many nitrogen- and phosphorus-containing organic compounds in soils have on average a higher affinity for adsorption to mineral surfaces than nutrient-free organic compounds. This leads to preferential enrichment of organic nitrogen and phosphorus on mineral surfaces and has important implications for the architecture of organo-mineral associations in soils. Furthermore, the preferential adsorption of organic nitrogen and organic phosphorus compounds likely also influences carbon, nitrogen, and phosphorus cycling in terrestrial ecosystems since sorption of organic compounds to minerals slows down their decomposition. This contribution reviews studies on the sorption of soil organic nitrogen and phosphorus to minerals, guided by the questions; what compounds are soil organic nitrogen and phosphorus composed of and why do these compounds have a comparably high affinity to adsorb to minerals? How do soil properties influence adsorption of organic nitrogen and phosphorus to minerals and why does preferential adsorption of organic nitrogen and phosphorus matter for element cycling? Furthermore, this article identifies hypotheses for future research about the structure of organo-mineral associations, biochemical element cycling, and the role of stoichiometry for soil organic matter dynamics. • Organic nitrogen and phosphorus (ON and OP) preferentially adsorb to minerals. • ON and OP compounds can form inner-sphere complexes with minerals. • Adsorption of ON and OP is pH-dependent. • ON and OP have a particularly high affinity for adsorption to short range order oxides. • Preferential adsorption of ON and OP has important implications for element cycling. [ABSTRACT FROM AUTHOR]

The chirality of sp2 nitrogen atoms in organic compounds is a somewhat unexpected and subtle effect already detected in the crystal state. However, revealing this effect in solution is rather challenging. A theoretical‐computational study, supported by electronic circular dichroism spectra has captured such an elusive feature. More information can be found in the Research Article by L. Palombi, M. Aschi and co‐workers (DOI: 10.1002/chem.202400232)...By Laura Palombi; Marta Monti; Erica Scarel; Valerio Morlacci; Mauro Stener and Massimiliano AschiReported by Author; Author; Author; Author; Author; Author [Extracted from the article]

Ammonia is the simplest molecule for the installation of nitrogen atom in organic compounds. It is abundantly available, economic and highly attractive from the point of atom economy for its use in organic synthesis, however, an highly challenging task for accessing the nitrogenous scaffolds through N−H activation of ammonia. With the advancement of synthetic procedures, scientific community continually developing excellent reactions employing ammonia as a source of nitrogen for various types of amination reactions and accomplishing the synthesis of nitrogenous compounds. This Review provides recent developments in amination reactions employing ammonia as a nitrogen source at a single platform. [ABSTRACT FROM AUTHOR]

The hydrogenation of polyaromatic compounds (PACs) present in mineral oils is of great importance when it comes to the desired product properties and the minimization of health hazards; however, the presence of organonitrogen inhibits the conversion of these compounds. In this study, the inhibition effects of different types of organonitrogen compounds (acridine (ACR) and carbazole (CBZ)-basic and nonbasic organonitrogen) on the hydrodearomatization (HDA) of phenanthrene over a sulfided commercial NiMo/Al2O3 catalyst were investigated in a microflow trickle-bed reactor at a temperature range of 280 to 320 °C and at a total pressure of 120 barg. Analysis of the experimental results shows that the hydrogenation of phenanthrene is significantly decreased in the presence of organonitrogen, with acridine showing stronger inhibiting effects. The extent of hydrodenitrogenation (HDN) is shown to correlate with the inhibition degree with a higher extent of HDN being achieved for carbazole than for acridine. Results from co-feeding different nitrogen types (acridine and carbazole) indicate that basic nitrogen is the dominating type of organonitrogen inhibitor. Recovery of catalyst activity in the absence of organonitrogen indicates fully reversible deactivation suggesting that inhibition relates to competitive adsorption and slower reaction rate of HDN compared to HDA. [ABSTRACT FROM AUTHOR]

This research estimates the efficiency of domestic wastewater treatment in the removal of organic pollutants and nitrogen compounds with a two-stage treatment sequence (an activated sludge reactor in the first stage, and a trickling filter in the second stage), and with the application of floating carriers in the activated sludge reactor. The materials "Polyvom", "Polystyrene" and "Bioballs" were adopted as floating carriers with previously determined filling ratios in the reactor volume of 10%, 20% and 20%, respectively. After the first stage of the study, it was found that the most effective treatment was achieved using the "Polyvom" material. Therefore, only this floating carrier was considered in the second and third stages of the study. Within the stages of the research, lab-scale benches operated under different operation modes of the treatment sequence. At the end of the study, it was possible to achieve the following levels of purification: BOD5 (2.1 mg/L), NH4 (0.4 mg/L), NO2 (1.0 mg/L), and NO3 (25 mg/L). The mean values of the concentrations of BOD, NH4, and NO3 met the requirements, but the concentration of NO2 exceeded the requirements (1.0 mg/L vs. 0.08 mg/L). These results were achieved under a hydraulic retention time in the activated sludge reactor of 8 h, and the MLSS for the free-floating and immobilized activated sludge was 0.2 and 0.9 g/L, respectively. [ABSTRACT FROM AUTHOR]

Sepsis is a systemic inflammatory response triggered by an infectious agent and is recognized by the World Health Organization as a global concern, since it is one of the major causes of severe illness in humans and animals. The study of the changes that can occur in saliva and serum in sepsis can contribute to a better understanding of the pathophysiological mechanisms involved in the process and also to discover potential biomarkers that can help in its diagnosis and monitoring. The objective of this study was to characterize the changes that occur in the salivary and serum proteome of pigs with experimentally-induced sepsis. The study included five pigs with sepsis induced by LPS administration and five pigs with non-septic inflammation induced by turpentine for comparative purposes. In saliva, there were eighteen salivary proteins differentially expressed in the sepsis condition and nine in non-septic inflammation. Among these, significant increments in aldolase A and serpin B12 only occurred in the sepsis model. Changes in aldolase A were validated in a larger population of pigs with sepsis due to Streptococcus suis infection. In serum, there were 30 proteins differentially expressed in sepsis group and 26 proteins in the non-septic group, and most of the proteins that changed in both groups were related to non-specific inflammation. In the saliva of the septic animals there were some specific pathways activated, such as the organonitrogen compound metabolic process and lipid transport, whereas, in the serum, one of the main activated pathways was the regulation of protein secretion. Overall, saliva and serum showed different proteome variations in response to septic inflammation and could provide complementary information about the pathophysiological mechanisms occurring in this condition. Additionally, salivary aldolase A could be a potential biomarker of sepsis in pigs that should be confirmed in a larger population. [ABSTRACT FROM AUTHOR]

Municipal solid waste landfills are significant sources of atmospheric methane, the second most important greenhouse gas after carbon dioxide. Large emissions of methane from landfills contribute not only to global climate change, but also to local ozone formation due to the enhancement of radical chain lengths in atmospheric reactions of volatile organic compounds and nitrogen oxides. Several advanced techniques were deployed to measure methane emissions from two landfills in the Southeast Michigan ozone nonattainment area during the Michigan–Ontario Ozone Source Experiment (MOOSE). These techniques included mobile infrared cavity ringdown spectrometry, drone-mounted meteorological sensors and tunable diode laser spectrometry, estimation of total landfill emissions of methane based on flux plane measurements, and Gaussian plume inverse modeling of distributed methane emissions in the presence of complex landfill terrain. The total methane emissions measured at the two landfills were of the order of 500 kg/h, with an uncertainty of around 50%. The results indicate that both landfill active faces and leaking gas collection systems are important sources of methane emissions. [ABSTRACT FROM AUTHOR]

Genus Mentha includes plants employed by the chemical, pharmaceutical and food industries, multiplied by vegetal propagation. In fact, these plants produce a high percentage of sterile seeds. The performance of different concentrations of organic compounds and of minerals nitrogen and boron in the development of mint seedlings produced by cuttings is evaluated. Cuttings were made by the median section of the branch, 10 cm in length and three to four knots. Treatments comprised two liquid commercial formulations, soluble in water: the first contained organic carbon and used with doses 0; 0.025; 0.05; 0.10%; the second contained nitrogen and boron, with doses 0; 0.03; 0.06; and 0.12%. Control contained distilled water. Experimental design was totally randomized, with factorial scheme 2 x 4 (formulations and doses), with four replications of seven cuttings for each treatment. Number of leaves, buds, height of aerial part, length of the largest root, biomass of fresh and dry material of the aerial part and of root system were evaluated. Data underwent analysis of variance and means grouped by Scott-Knott test at 5%. Effects of doses of each formulation underwent analysis of regression. Addition to substrate of nitrogen and boron at concentrations 0.03% and 0.06%, immediately after cutting, may be recommended to stimulate the expansion of the volume of the root system and the development of the aerial part, with the production of mint seedlings with satisfactory commercial quality. [ABSTRACT FROM AUTHOR]

Sweetpotato (Ipomoea batatas [L.] Lam) is a widely cultivated food crop with generally good adaptability. However, drought stress can cause a significant decline in yield. To reveal the response mechanism of sweetpotato to drought stress, an integrated physiological, proteomic and metabolomic investigation was conducted in leaves of two sweetpotato varieties with differing responses to drought stress, drought-resistant Wanzishu56 (WZ56) and a more sensitive variety, Ningzishu2(NZ2). Physiological analysis showed that the variety with better drought tolerance had superior performance in water retention capacity and photosynthetic efficiency under drought stress. A total of 1140 proteins were identified within the two varieties. Among them, 192 differentially expressed proteins were detected under drought conditions, including 97 that were up-regulated. Functional analysis showed that these up-regulated proteins were primarily involved in photosynthesis, reactive oxygen species metabolism, organonitrogen compound metabolism, and precursor metabolite catabolism and energy generation. All differentially expressed proteins in WZ56 that were involved in photosynthetic and glutathione metabolic processes were up-regulated. Enzyme activity assays were carried out to validate the proteomics data. Moreover, 75 metabolites were found to have a higher expression level in WZ56 than NZ2 under drought stress. The higher concentration of carbohydrates, amino acids, flavonoids and organic acids found in drought-stressed leaves of WZ56 suggested that these metabolites may improve the drought resistance of sweetpotato. This study uncovered specific-proteins and metabolites associated with drought resistance, providing new insights into the molecular mechanisms of drought tolerance in sweetpotato. [ABSTRACT FROM AUTHOR]

A molybdenum–nitride complex bearing a pyridine-based PNP-type pincer ligand derived from dinitrogen is reacted with various kinds of carbon-centered electrophiles to functionalize the nitride ligand in the molybdenum complex. Methylation with MeOTf and acylation with diphenylacetyl chloride of the nitride complex afford the corresponding imide complexes via a carbon–nitrogen bond formation. In the case of reactions with phenylisocyanate and diphenylketene, the PNP ligand works as a non-innocent ligand to form the corresponding ureate and acylimide complexes, respectively. These newly synthesized complexes are characterized by X-ray analysis. As a further transformation of the prepared imide complexes, hydrolysis of the molybdenum–acylimide complex proceeds to give the corresponding amide as an organonitrogen compound together with the corresponding molybdenum–oxo complex. This result indicates that the nitrogen molecule is converted into organic amide mediated by the molybdenum–nitride complex. [ABSTRACT FROM AUTHOR]

Plastids are important plant cell organelles containing a genome and bacterial-type 70S ribosomes—primarily composed of plastid ribosomal proteins and ribosomal RNAs. In this study, a chlorophyll-deficient mutant (cdm) obtained from double-haploid Chinese cabbage 'FT' was identified as a plastome mutant with an A-to-C base substitution in the plastid gene encoding the ribosomal protein RPS4. To further elucidate the function and regulatory mechanisms of RPS4, a comparative proteomic analysis was conducted between cdm and its wild-type 'FT' plants by isobaric tags and a relative and absolute quantitation (iTRAQ)–based strategy. A total of 6,245 proteins were identified, 540 of which were differentially abundant proteins (DAPs) in the leaves of cdm as compared to those of 'FT'—including 233 upregulated and 307 downregulated proteins. Upregulated DAPs were mainly involved in translation, organonitrogen compound biosynthetic process, ribosomes, and spliceosomes. Meanwhile, downregulated DAPs were mainly involved in photosynthesis, photosynthetic reaction centres, photosynthetic light harvesting, carbon fixation, and chlorophyll binding. These results indicated an important role of RPS4 in the regulation of growth and development of Chinese cabbage, possibly by regulating plastid translation activity by affecting the expression of specific photosynthesis- and cold stress–related proteins. Moreover, a multiple reaction monitoring (MRM) test and quantitative real-time polymerase chain reaction analysis confirmed our iTRAQ results. Quantitative proteomic analysis allowed us to confirm diverse changes in the metabolic pathways between cdm and 'FT' plants. This work provides new insights into the regulation of chlorophyll biosynthesis and photosynthesis in Chinese cabbage. [ABSTRACT FROM AUTHOR]

Chitin biorefinery offers a unique opportunity to sustainably produce highly-valued organonitrogen compounds such as the versatile pharmaceutical precursor 3-acetamido-5-acetylfuran (3A5AF), bypassing the Haber process and mitigating the consumption of fossil feedstocks. However, the reported protocols engaged large quantities of toxic organic solvents and required harsh conditions. In this work, a highly efficient catalytic system has been developed in the nontoxic, biobased γ-valerolactone (GVL) solvent under relatively mild conditions. 3A5AF was selectively obtained with an unprecedent yield of 75.3% at 140 °C for 2 h by adding NH 4 SCN and HCl. The high yielding was exclusively promoted by a dissolution-dehydration effect. Based on the UPLC-TOF-MS and NMR analyses, the presence of NH 4 SCN has induced a very rapid NAG conversion possibly by coordinating with the acetamido group and the hydroxyl groups, and the 3A5AF product was obtained in a subsequent dehydration pathway from NAG with the Chromogen I and Chromogen III as the intermediates. [Display omitted] • 3A5AF was obtained with an unprecedent yield of 75.3%. • The high yielding was exceptionally promoted by a dissolution-dehydration effect. • A relatively mild reaction system was developed in the nontoxic, biobased GVL. [ABSTRACT FROM AUTHOR]

Excess CO 2 and NO 3 - released by human industrial activities have contributed to the deterioration of the global environment. Simultaneous activation and reduction of CO 2 and NO 3 - to produce high-value chemical products is not only effective in solving environmental problems but can also recycle waste pollutants and is essential for the strategic realization of carbon neutrality. Compared with conventional artificial nitrogen and carbon fixation processes, electrochemical C-N coupling of CO 2 and NO 3 - under ambient conditions is an emerging approach. However, the understanding of C-N coupling is still in its infancy, as CO 2 and NO 3 - are first reduced individually to produce different C and N intermediates, which are further coupled to form different types of organic nitrogen compounds through a series of PCET processes. However, this process is often accompanied by the generation of many byproducts. To improve the selectivity of the target products, the design and modulation of catalyst active sites are important. In this paper, a detailed review of the different mechanisms of electrocatalytic coreduction of CO 2 and NO 3 - is presented. From the perspective of controlling competitive reactions, the elements that can achieve C-N coupling in electrocatalysis are divided into p-block elements and d-block elements. The regulatory methods are summarized, and the development potential of each block element is described in terms of the mechanism. Finally, suggestions and challenges for future electrocatalytic coreduction of CO 2 and NO 3 - research are presented. [Display omitted] • Using nitrate as a nitrogen source can achieve energy saving and environmental protection. • Rational coupling of *CO 2 and *NO 2 is a promising mechanism for the application. • Inhibition of HER by the unique semiconducting properties of p-block elements. • Modulation of the active site can improve the catalytic C-N coupling performance. [ABSTRACT FROM AUTHOR]

In pursuit of a more green and sustainable society, the preparation of versatile chemicals from renewable biomass is essential. Nitrogen-containing chemicals, as compared with hydrocarbon fuels or oxygen-containing compounds, usually have higher values and play key roles in modern industry. The industrial synthesis of nitrogen-containing chemicals relies heavily on the Haber–Bosch process, a high-energy-consumption and environment-polluting process. Therefore, the production of these organonitrogen chemicals from biomass has attracted increasing interest in recent years. Chitin is the most abundant nitrogen-containing biopolymer on earth, and its monomer N-acetylglucosamine (GlcNAc) not only has great application values in multiple areas, but also is a key intermediate for the conversion of chitin to other organonitrogen compounds. This review provides a comprehensive summary and perspective of the latest cutting-edge innovations on biomass conversion to GlcNAc. Biological methods, chemical methods as well as combined methods for GlcNAc preparation are systematically elaborated, and their respective advantages and disadvantages in terms of product yield, process safety, economy, efficiency, and environmental friendliness are discussed. To achieve an economic, environmentally friendly, and efficient production of GlcNAc from renewable biomass, the development of combined methods that involve multiple actions in a synergistic way under mild and green conditions should be the focus of future research. [ABSTRACT FROM AUTHOR]

Chitin is a potential resource for the production of renewable organonitrogen compounds, as it contains biologically fixed nitrogen. Hydrolysis of chitin followed by hydrogenation gives the sugar alcohol named 2-acetamido-2-deoxysorbitol (ADS). The dehydration condensation of ADS produces 2-acetamido-2-deoxyisosorbide (ADI), which is a prospective precursor of nitrogen-containing polymers. However, the conversion of ADS to ADI in previous works needed a large amount of CF3SO3H as a superstrong acid catalyst, which is high cost and requires special corrosion-resistant equipment. In this work, we have found that H3PO3, a weak acid, can convert ADS to ADI. Possibly, H3PO3 alters the reaction mechanism from a simple acid-catalysed dehydration cyclisation to a cyclisation via phosphite esters. Density functional theory calculations suggest that the modified pathway via the phosphite esters significantly reduces the activation energy. In addition, the reducing ability of the acid likely decreases the formation of condensation by-products. [ABSTRACT FROM AUTHOR]

Here, deep sequencing results of the maize transcriptome in leaves and roots were compared under high‐nitrogen (HN) and low‐nitrogen (LN) conditions to identify differentially expressed circRNAs (DECs).Circular RNAs (circRNAs) are covalently closed non‐coding RNA with widely regulatory potency that has been identified in animals and plants. However, the understanding of circRNAs involved in responsive nitrogen deficiency remains to be elucidated.A total of 24 and 22 DECs were obtained from the leaves and roots, respectively. Ten circRNAs were validated by divergent and convergent primers, and 6 DECs showed the same expression tendency validated by reverse transcriptase‐quantitative PCR. Integrating the identified differentially expressed miRNAs, 34 circRNAs could act as miRNA decoys, which might play important roles in multiple biological processes, including organonitrogen compound biosynthesis and regulation of the metabolic process. A total of 51 circRNA‐parent genes located in the genome‐wide association study identified loci were assessed between HN and LN conditions and were associated with root growth and development.In summary, our results provide valuable information regarding further study of maize circRNAs under nitrogen deficiency and provide new insights into screening of candidate genes as well as the improvement of maize regarding nitrogen deficiency resistance. CircRNA–miRNA–mRNA co‐expression networks were constructed to explore the circRNAs that participated in biological development and nitrogen metabolism. [ABSTRACT FROM AUTHOR]

Compounds adsorbed onto PM10 in the air near the cement plant were determined. Several side reactions that occur in the hot flue gas stream at the same time as the actual main reactions are also possible. This leads to the formation of traces of organic nitrogen compounds. For the GC/MS determination of polar organic compounds silylation as a derivatization method was used. Organic compounds detected are derivatives of sugars, sugar alcohols, and mono-, di- and tri-carboxylic acids. The composition is characteristic for pollution of the urbane atmosphere. Nitrogen organic compounds formed during the urea thermolytic process in hot cement kiln gases represent parabanic acid, 5-hydroxyhydantoin, 4,5-dihydroxyhydantoin, 5-oxoproline, and cyanuric acid. The inorganic part of aerosols detected includes oxyanions of sulfamic acid, sulfate, sulfite, phosphate, and vanadate(V) with ammonium as a cation. Chemical compositions of particles are crucial to assess the health impacts since the biological responses to aerosols are not always linked with major constituents but rather with toxicologically potent minor components. [ABSTRACT FROM AUTHOR]

One of the main problems in oil production to this day is high percentage of flaring of associated petroleum gases (APG) and therefore a low level of their utilization. In addition, every year; spending aimed at developing technologies to reduce emissions of volatile organic compounds and nitrogen oxide into the atmosphere is growing. Based on the analysis of existing practices, the economic prospects are evaluated and recommendations for the targeted use of APG are formulated. The study briefly outlines technologies for reducing on-site flaring that are applicable in hard-to-recover oil fields. Information on technologies is collected and evaluated from a review of previous studies, technical documents, and analysis of open international sources. [ABSTRACT FROM AUTHOR]

The synthesis of organonitrogen compounds via C−N bond formation emerges as a versatile route for drug discovery. Most of the pharmaceuticals and natural products, which are predominantly used generally contain amine functionalities and amide linkages in their structure. Traditionally, the synthesis is done by using several metal catalysts and hazardous chemicals. The organocatalyzed synthetic protocol provides a sustainable and eco‐compatible route for the synthesis of organonitrogen compounds and at the same time also avoids metal contamination. The main aim of this Review is to provide an overview of the organocatalyzed amine and amide synthesis via C−N bond formation reactions. We hope this Review provides valuable information about the organocatalyzed reaction to enable the development of more sustainable routes to form these linkages. [ABSTRACT FROM AUTHOR]

Diatoms are unicellular photosynthetic algae known to secrete organic matter that fuels secondary production in the ocean, though our knowledge of how their physiology impacts the composition of dissolved organic matter remains limited. Like all photosynthetic organisms, their use of light for energy and reducing power creates the challenge of avoiding cellular damage. To better understand the interplay between redox balance and organic matter secretion, we reconstructed a genome-scale metabolic model of Thalassiosira pseudonana strain CCMP 1335, a model for diatom molecular biology and physiology, with a 60-year history of studies. The model simulates the metabolic activities of 1,432 genes via a network of 2,792 metabolites produced through 6,079 reactions distributed across six subcellular compartments. Growth was simulated under different steady-state light conditions (5–200 μmol photons m-2 s-1) and in a batch culture progressing from exponential growth to nitrate-limitation and nitrogen-starvation. We used the model to examine the dissipation of reductants generated through light-dependent processes and found that when available, nitrate assimilation is an important means of dissipating reductants in the plastid; under nitrate-limiting conditions, sulfate assimilation plays a similar role. The use of either nitrate or sulfate uptake to balance redox reactions leads to the secretion of distinct organic nitrogen and sulfur compounds. Such compounds can be accessed by bacteria in the surface ocean. The model of the diatom Thalassiosira pseudonana provides a mechanistic explanation for the production of ecologically and climatologically relevant compounds that may serve as the basis for intricate, cross-kingdom microbial networks. Diatom metabolism has an important influence on global biogeochemistry; metabolic models of marine microorganisms link genes to ecosystems and may be key to integrating molecular data with models of ocean biogeochemistry. [ABSTRACT FROM AUTHOR]

High‐performance red quantum dot light‐emitting diodes (QLEDs) are demonstrated based on nitrogen heterocycle‐containing compounds as the organic electron transporting layer (ETL). Unlike ZnO, the adoption of organic ETL can eliminate unwanted photoluminescence quenching of colloidal quantum dots (QDs) due to the prevented electron transfer between QDs and organic ETL. Most importantly, when the central core is varied from benzene and pyrimidine to triazine, their lowest unoccupied molecular orbital energy levels are found to be well tuned to facilitate electron injection. Consequently, a triazine‐cored organic ETL (denoted as TmPPPyTz) achieves a restored charge balance, giving a record‐high external quantum efficiency of 13.4% (18.8 cd A−1, 23.9 lm W−1) and Commission Internationale de l'Eclairage coordinates of (0.68, 0.32). The obtained state‐of‐art performance clearly indicates the great potential of organic ETL towards efficient QLEDs. [ABSTRACT FROM AUTHOR]

Nutrients mobilized by stormwater can exacerbate eutrophication in receiving waters. While bioretention systems are increasingly employed to improve stormwater quality, they do not normally incorporate design attributes for removal of dissolved organic nitrogen (DON). Thus, the current study concentrated on continuous column adsorption of stormwater DON using a media mixture of coal activated carbon and quartz sand. Adsorption of eight model organic nitrogenous compounds was studied and only pyrrole showed an appreciable adsorption performance; other organic nitrogen compounds were weakly adsorbed. The breakthrough depth for pyrrole was 88 m (equivalent to 4.4 m simulated rainfall depth), at a superficial velocity of 61 cm/hr and influent DON concentration of 1 mg N/L. Subsequent experiments revealed that adsorption of pyrrole was minimally affected by superficial velocity, such that its DON removal efficiency was greater than 91% for all tested superficial velocities (7–489 cm/hr). Accordingly, adsorption processes may be employed for removing stormwater DON fractions behaving similarly to pyrrole; data suggest DON removal initially at greater than 95%, gradually falling to 30% through 25 years of service. Practitioner points: Adsorption of eight different organic nitrogenous compounds onto coal‐based activated carbon was investigated.Amino acids and an amino sugar were weakly adsorbed onto the activated carbon.Pyrrole, a moderately hydrophobic heterocyclic organic nitrogen compound was effectively adsorbed.A 30‐cm depth was considered as adequate for removal of pyrrole and compounds that would similarly adsorb.Evidence of biological ammonification was present in all studies except for pyrrole. [ABSTRACT FROM AUTHOR]

[Display omitted] • Both MFC-CW and EC-CW perform better OFLO removal. • The better nitrogen removal occurred in MFC-CW. • The effect of MFC and EC on microbial resistance in CW was different. • EC tends to increase the membrane transport and signal transduction in CW. • MFC tends to improve organic compound metabolism and nitrogen transformation in CW. Given its advantages in terms of high efficiency and low energy consumption, bioelectrochemistry - integrated constructed wetlands (BEC-CWs) have been applied widely in the various pollutant removal. However, the study on the synchronous removal performance, difference and molecular mechanism of various pollutants in different BEC-CWs is limited. This study explored the difference of performance and mechanisms on the antibiotics and nitrogen simultaneous removal by microbial fuel cell - integrated CW (MFC-CW) and direct current - integrated CW (EC-CW). Results showed that MFC-CW and EC-CW were all performed better ofloxacin (OFLO) removal (>99 %), where the biodegradation was the key contributor (91.00–94.70 %). The MFC can better promote the substrate adsorption, while EC was more conducive to improve plant uptake for OFLO removal in CWs. MFC-CW (78.86 ± 11.61 %) performed better total nitrogen removal than EC-CW (58.84 ± 12.86 %). The anammox gene (107 ∼ 108 copies·g−1) played an important role in the nitrogen removal. The denitrification performance of BEC-CWs was inhibited due to OFLO addition, especially in EC-CW. MFC-CW inhibited the quinolone resistance genes generation and improved nitrogen removal efficiency by increasing the abundances of related microorganisms. The bioelectricity can improve the microbial diversity in CWs compared to direct current. The OFLO degradation in EC-CW were initiated with defluorination, dealkylation, decarboxylation, and opening of piperazinyl ring, while it was defluorination, dealkylation, and decarboxylation in MFC-CW. EC-CW tended to increase the membrane transport and signal transduction, while MFC tended to improve organic compound metabolism and nitrogen transformation. These findings provide new insights into the difference between bioelectricity and direct current on the synchronous removal of various pollutants in the constructed wetlands. [ABSTRACT FROM AUTHOR]

We had recently disclosed the oxidation of pyrazole-4-carbaldehydes using a vanadium catalyst in the presence of 30% H SB 2 sb O SB 2 sb in acetonitrile.[11] Six commercially available vanadium catalysts had been screened and VO(acac) SB 2 sb was found to be the most suitable catalyst. According to the previous report,[11] the oxidation of pyrazole-4-carbaldehydes with VO(acac) SB 2 sb /30% H SB 2 sb O SB 2 sb in acetonitrile at 70 °C within 8 hours gave the corresponding pyrazole-4-carboxylic acid in 71-95% yield. Notably, the VO(acac) SB 2 sb /30% H SB 2 sb O SB 2 sb system in DMF is the best combination for the oxidation of B 5a b to the corresponding acid B 6a b (Table 1, entry 5). [Extracted from the article]

Electrocatalytic oxidation is an attractive process for valorizing the organic compounds and removing the nitrogen in aqueous waste streams at ambient conditions. We evaluated the electrocatalytic oxidation reaction as a function of applied potential over Pt electrodes of an aqueous stream generated via hydrothermal liquefaction. We quantified the conversion of particular organic compounds (e.g., carboxylic acids, alpha hydroxyacids, alcohols, ketones, and amides) and the removal of carbon, nitrogen, sulfur, and chemical oxygen demand. Organic nitrogen and sulfur were oxidized to nitrates and sulfates. The main reaction products from the electrocatalytic oxidation at the anode were short chain volatile hydrocarbons (i.e., olefins, and paraffins) and CO2, while H2 was generated at the cathode. Unidentified compounds were converted to short chain carboxylic acids, alcohol and ketones, while ammonia was oxidized into N2. Studies with model compounds showed that amides and alpha hydroxyacids yielded carboxylic acids that convert further via (non-)Kolbe chemistry. Simultaneous denitrification, valorization of organic compounds, and H2 generation from the aqueous stream can potentially simplify the unit operations currently used in a hydrothermal process. The cost of the electricity required to drive the electrocatalytic operation can be partially mitigated by selling the excess H2 produced. [ABSTRACT FROM AUTHOR]

The purification of water and air by semiconductor photocatalysis is a rapidly growing area for academic research and industrial innovation, featured with ambient removal of organic or inorganic pollutants by using solar light as the energy source and atmospheric O2 as the green oxidant. Both charge transfer and energy transfer from excited photocatalysts can overcome the spin-forbidden nature of O2. Layered bismuth oxyhalides are a new group of two-dimensional photocatalysts with an appealing geometric and surface structure that allows the dynamic and selective tuning of O2 activation at the surface molecular level. In this Feature Article, we specifically summarize our recent progress in selective O2 activation by engineering surface structures of bismuth oxyhalides. Then, we demonstrate selective photocatalytic O2 activation of bismuth oxyhalides for environmental control, including water decontamination, volatile organic compound oxidation and nitrogen oxide removal, as well as selective catalytic oxidations. Challenges and opportunities regarding the design of photocatalysts with satisfactory performance for potential environmental control applications are also presented. [ABSTRACT FROM AUTHOR]

Plants can respond and adapt to changes in the internal content of carbon and nitrogen by using organic compounds that widely differ in their carbon/nitrogen ratio. Among them, the amides asparagine and glutamine are believed to be preferred by most plants, including Arabidopsis. However, increases in the ureides allantoin and/or allantoate concentrations have been observed in different plant species under several environmental conditions. In this work, changes in the ratio between carbon skeletons and reduced nitrogen were investigated by varying the concentrations of nitrogen and sucrose in the growth media. Allantoin accumulation was observed when plants were grown in media with high ammonia concentrations. This increase was reverted by adding sucrose as additional carbon source. Moreover, mutant plants with a decreased capability to degrade allantoin showed a compromised growth compared to WT in ammonia supplemented media. Together, our results indicate that allantoin accumulation is induced by low carbon/nitrogen ratio and suggest that its degradation is critical for proper plant growth and development. [ABSTRACT FROM AUTHOR]

While soil physico-chemical and solute properties mainly affect N diffusion directly, root and microbial properties have a strong indirect effect on diffusion by critically controlling N production and consumption rates and thus N pool sizes. Keywords: amino acid speciation; diffusion; microdialysis; soil nitrogen (N) dynamics; soil organic N fluxes EN amino acid speciation diffusion microdialysis soil nitrogen (N) dynamics soil organic N fluxes 2104 2106 3 08/19/21 20210915 NES 210915 Soils typically contain a large variety of nitrogen (N) forms, including inorganic N and a range of organic N compounds of varying molecular size (Warren, 2013). [Extracted from the article]

The specific features in the distribution of organic and mineral nitrogen compounds in marsh and tundra soils of the European Russian Arctic (coastal areas of the Barents and White Seas) were analyzed. Total nitrogen was determined by gas chromatography (CHNS-O elemental analyzer), and inorganic nitrogen, by photometry. The composition of hydrolyzable amino acids was analyzed by liquid chromatography on ion exchange resins. Mineral compounds accounted for an insignificant part of the total soil nitrogen; its major part (to 97% of the total content) was represented by organic substances (Nоrg). The Nоrg varied within a wide range in both marsh (0.3–15.8 g/kg) and tundra soils (5–20 g/kg in the peat horizons and 0.3–2 g/kg in the mineral horizons). The content of N- varied from 5 to 20 mg/kg in marsh soils and from 30 to 200 mg/kg in tundra soils. In marsh soils, the content of nitrate nitrogen was 0.2–4.6 mg/kg in the upper horizons. Marsh soils were characterized by the accumulation of Nоrg either on the surface or in the middle part of the profile in the presence of humus-accumulative horizons buried under recent marine sediments. The accumulation of Nоrg and N- was observed above the permafrost in the peat-gley soil and in the permafrost in the oligotrophic peat soil. The content of hydrolyzable amino acids in the soils of different geneses was 0.6–8 g/kg, which corresponded to 30–60% of the soil organic nitrogen and 2–12% of the soil organic carbon. Distribution patterns of the amino acid nitrogen and organic nitrogen in the soil profiles were similar. The qualitative composition of amino compounds was relatively uniform, and the ratios of most of them were close. The shares of arginine, histidine, phenylalanine, tyrosine, and isoleucine were less than 4% each; of lysine, valine, proline, serine, and threonine, 5 to 7%; and of alanine and leucine, 10–12%. The share of glycine increased downward the profile from 12 to 20%, and the shares of aspartic and glutamic acids decreased from 11 to 6%. In marsh soils, Nоrg, N- , and nitrogen of most amino acids correlated (r = 0.6–0.9) with the clay content and nonsilicate iron forms. The tightest correlations were observed between the dithionite-soluble iron and the nitrogen of threonine and histidine. [ABSTRACT FROM AUTHOR]

Background: The grain yield of cereals is determined by the synergistic interaction between source activity and sink capacity. However, source-sink interactions are far from being fully understood. Therefore, a field experiment was performed in wheat to investigate the responses of flag leaves and grains to sink/source manipulations. Results: Half-degraining delayed but partial defoliation enhanced leaf senescence. Sink/source manipulations influenced the content of reactive oxygen species in the flag leaf and the concentration of phytohormones, including cytokinins, indoleacetic 3-acid and jasmonic acid, in the flag leaves (LDef) and grains (GDef) in defoliated plants and flag leaves (LDG) and grain (GDG) in de-grained plants. Isobaric tag for relative and absolute quantitation (iTRAQ)-based quantitative proteomic analysis indicated that at 16 days after manipulation, a total of 97 and 59 differentially expressed proteins (DEPs) from various functional categories were observed in the LDG and LDef groups, respectively, compared with the control, and 115 and 121 DEPs were observed in the GDG and GDef groups, respectively. The gene ontology annotation terms of the DEPs mainly included carbon fixation, hydrogen peroxide catabolic process, chloroplast and cytoplasm, oxidoreductase activity and glutamate synthase activity in the flag leaves of manipulated plants and organonitrogen compound metabolic process, cytoplasm, vacuolar membrane, CoA carboxylase activity, starch synthase activity and nutrient reservoir activity in the grains of manipulated plants. KEGG pathway enrichment analysis revealed that photosynthesis, carbon, nitrogen and pyruvate metabolism and glycolysis/gluconeogenesis were the processes most affected by sink/source manipulations. Sink/source manipulations affected the activities of amylase and proteinases and, ultimately, changed the mass per grain. Conclusions: Manipulations to change the sink/source ratio affect hormone levels; hydrolytic enzyme activities; metabolism of carbon, nitrogen and other main compounds; stress resistance; and leaf senescence and thus influence grain mass. [ABSTRACT FROM AUTHOR]

The Community Earth System Model version 2 (CESM2) includes a detailed representation of chemistry throughout the atmosphere in the Community Atmosphere Model with chemistry and Whole Atmosphere Community Climate Model configurations. These model configurations use the Model for Ozone and Related chemical Tracers (MOZART) family of chemical mechanisms, covering the troposphere, stratosphere, mesosphere, and lower thermosphere. The new MOZART tropospheric chemistry scheme (T1) has a number of updates over the previous version (MOZART‐4) in CESM, including improvements to the oxidation of isoprene and terpenes, organic nitrate speciation, and aromatic speciation and oxidation and thus improved representation of ozone and secondary organic aerosol precursors. An evaluation of the present‐day simulations of CESM2 being provided for Climate Model Intercomparison Project round 6 (CMIP6) is presented. These simulations, using the anthropogenic and biomass burning emissions from the inventories specified for CMIP6, as well as online calculation of emissions of biogenic compounds, lightning NO, dust, and sea salt, indicate an underestimate of anthropogenic emissions of a variety of compounds, including carbon monoxide and hydrocarbons. The simulation of surface ozone in the southeast United States is improved over previous model versions, largely due to the improved representation of reactive nitrogen and organic nitrate compounds resulting in a lower ozone production rate than in CESM1 but still overestimates observations in summer. The simulation of tropospheric ozone agrees well with ozonesonde observations in many parts of the globe. The comparison of NOx and PAN to aircraft observations indicates the model simulates the nitrogen budget well. Plain Language Summary: The set of chemical reactions for tropospheric chemistry used in the Community Earth System Model version 2 (CESM2) has been updated significantly over CESM1 in the Community Atmosphere Model with chemistry (CAM‐chem) and Whole Atmosphere Community Climate Model (WACCM) configurations. The emissions used for the CESM2 simulations are documented here, with anthropogenic and biomass burning emissions based on the specified inventories for Climate Model Intercomparison Project 6 (CMIP6), and emissions of biogenic compounds, lightning NO, dust, and sea salt are calculated online and dependent on the simulated meteorology. Evaluation of the CAM‐chem and WACCM configurations of CESM2 with observations indicate an underestimate of anthropogenic emissions of a variety of compounds, including carbon monoxide and hydrocarbons. The updated chemistry leads to an improvement in the simulation of tropospheric ozone. Key Points: This paper fully documents the significant updates to the chemistry mechanisms in version 2 of the Community Earth System ModelThe new tropospheric chemistry scheme improves representation of isoprene oxidation as well as other ozone precursors over earlier versionsThe simulation of tropospheric ozone is improved in comparison to observations [ABSTRACT FROM AUTHOR]

In the present work, the liquid‐solid interaction of liquid N‐heteroaromatic compounds, commonly present in the petroleum feedstocks of the refineries, with Y zeolites used as hydrocracking catalysts was followed using IR‐ATR spectroscopy. The inhibition of the zeolitic acid sites by strongly basic pyridine and weakly basic indole was highlighted using a continuous flow IR‐ATR cell. Results were assessed by Density Functional Theory calculations to compute the vibrational frequencies of pyridine and indole according to the nature of the interaction sites: silanol groups or acidic OH groups. The study points out that IR‐ATR spectroscopy opens the way for investigating the interaction modes of low vapor pressure molecules (e. g. indole) that present an inherent difficulty to be operated in the gas phase. Moreover, the IR‐ATR makes possible the analysis of the little‐explored low wavenumber zone (<800 cm−1), that presents informative vibrational modes on the adsorption mode of N‐molecules. Hence, this work points out that for pyridine, the bands at 686 and 727 cm−1 are characteristic of pyridinium species formed over zeolitic OH groups, meanwhile, the signals at 703 and 750 cm−1, are associated to pyridine in interaction with silanol groups. The IR‐ATR study reveals that indole, a weakly basic compound, can be protonated on acidic Y zeolites as unambiguously evidenced by the formation of the bands at 1617, 1608, 1543 and 705 cm−1. Findings here exposed are crucial for studying inhibitory effects exerted by weak nitrogenated compounds on acidic materials during hydrocracking processes. [ABSTRACT FROM AUTHOR]

Water extracts from soils of the Barents Sea coast (the Khaipudyr Bay) were analyzed for the contents of organic carbon and total nitrogen by the method of high-temperature catalytic oxidation with non-dispersive IR registration; the contents of low-molecular-weight acids, carbohydrates, and alcohols were determined by gas chromatography and gas chromatography–mass-spectrometry. The mass fraction of inorganic carbon was measured potentiometrically, and the content of inorganic nitrogen (N– N– ) was determined by photometry. In marsh soils (Tidalic Fluvisols (Arenic or Loamic, Epiprotosalic)), = 0.1–0.8, = 0.01–0.05 g/kg, = + 0.01, and = 7–21. The content of individual components does not exceed 20 mg/kg, including carbohydrates (50–90%), acids (10–50%), and alcohols (<3%). In peat horizons of tundra soils (Cryic Histosols and Histic Cryosols), = 4–10, ~ 0.2 g/kg, and = 25–56. Litter and peat horizons accumulate both individual humus components and total dissolved organic carbon. The total weight of the identified substances is 200–300 mg/kg, 80–90% of them are carbohydrates, 10–20% are acids, and 0–9% are alcohols. The accumulation of and (N– takes place above the permafrost table. It is argued that the ratios of organic forms of carbon and nitrogen in soil water extracts and the content of low-molecular weight organic compounds in soils can be used as indicators of pedogenic processes in the Far North. [ABSTRACT FROM AUTHOR]

The aim of this study is first to investigate piperazine behavior as an inorganic corrosion inhibitor for a ST-14 steel and then to explore synergistical effect of organic (sodium silicate) and inorganic (piperazine) corrosion inhibitors. Due to different corrosion inhibition behavior of these two chemicals, positive results are expected. The corrosion inhibition characteristics of sodium silicate (Na2SiO3) and nitrogen contained organic compound, piperazine (C4H10N2) as corrosion inhibitor for carbon steel was studied using weight loss, Tafel polarization, impedance and some spectrophotometric techniques. Also Fourier transform infrared spectroscopy (FT-IR), ultraviolet–visible spectroscopy (UV–Vis) and scanning electron microscope (SEM) tests were conducted in order to indicate the formation of a protective film on the surface of steel coupons. The obtained results indicated that the combination of these two inhibitors improve the corrosion behavior about 87 and 76% in accordance with potentiodynamic polarization tests and electrochemical impedance spectrometry, respectively. The corrosion inhibition efficiency has been increased using an optimum combination including 2 ppm piperazine (PIP) and 10–15 ppm sodium silicate. It should be noted that the corrosion inhibition action has been employed using remarkably low concentration of corrosion inhibitors. From the interaction between corrosion inhibitors molecules and iron oxide layer, it can be concluded that the physical adsorption has more effect compared to chemical adsorption in the film formation process for both sodium silicate and PIP inhibitors. It is proposed at least two mechanisms for synergism. [ABSTRACT FROM AUTHOR]