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Due to the rapid growth of the global economy, energy consumption has been steadily increasing, leading to increasing issues such as energy shortages and environmental concerns. Biomass energy, a critical renewable energy source, plays a vital role in advancing low-carbon energy development and resource sustainability. In this study, experiments were conducted to study the migration of C, H, and N elements of corn straw during the microwave heating process, and the effects of residence time, heating temperature, and microwave power were also investigated. The results showed that when the temperature rose, both the proportion of C and H elements fluctuated slightly. Specifically, when the temperature rose from 75 °C to 275 °C, there was a 1.02% increase in the proportion of the C element and a 0.25% decrease in the proportion of the H element. Residence time appeared to be a significant factor influencing the changes in C, H, and N elements. For a 40 min residence time, the proportion of the C element increased from 31.77% to 35.36%, while the proportion of the H element decreased from 4.50% to 3.83%. When there was an increase in the microwave power between 160 W and 200 W, higher temperatures were reached in the samples, leading to the carbonization process of corn straw being more complete. Consequently, the proportion of the C element rose with extended residence time, whereas the proportion of the H element decreased as the residence time increased. [ABSTRACT FROM AUTHOR]

Hydrophobic organic contaminated polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and CHNS (carbon, hydrogen, nitrogen and sulphur species) are explosively associated with road dust particles. A few organic contaminants are toxic in nature and have an unpleasant effect on human health. The International Agency for Research on Cancer (IARC), the US Department of Health and Human Services (HHS) and the United States–Environmental Protection Agency has considered several PAHs and PCBs as carcinogens for human beings. In the proposed study, the anthropogenic contaminants present in road dust were assessed in six representative diversified sites i.e. industrial, commercial, office, residential, construction and traffic intersection in Delhi NCR, India. Roadside dust samples were gathered in premonsoon, monsoon and postmonsoon seasons and characterized for PAHs, PCBs and CHNS. The concentration of total PAHs (16 Nos) and PCBs (6 Nos) of the selected sites ranged from 0.27 µg/kg to 605.80 µg/kg and 0.01 µg/kg to 41.26 µg/kg, respectively. The Fourier transform infrared spectroscopy-attenuated total reflectance study suggested that the presence of O = C = O, Si–O, carbonyl, acidic or aliphatic esters group were associated with road dust particles. Hydrogen and sulphur concentrations were not detected in the selected road dust samples. Carbon and nitrogen concentrations varied from 2.24% to 16.82% and 0.69% to 14.5%, respectively, seasonally. In the premonsoon season, road dust was distinguishably contaminated as compared to monsoon and postmonsoon season, which might be due to movement of contaminated road dust from adjacent locations. It was perceived that Delhi NCR organic contamination in road dust was much below as compared to other countries. It may be concluded that due to the presence of significant amounts of carbon and nitrogen concentrations in the road dust, to a greater extent, road dust can be fertile and might be advantageous for green belt development to mitigate air pollution. The utilization of road dust will further bring down the burden of landfill sites and may lead towards sustainability. [ABSTRACT FROM AUTHOR]

The exergy values of three oat straws were investigated. The effects of moisture content, ash content, S content, correlation factor (C, O, H, and N), and lower heating value (LHV) were also studied. The results showed that the moisture-related exergy, ash-related exergy, and S-related exergy varied in the ranges of 283.630–337.502, 28.474–111.054, and 4.357–13.944 kJ/kg, respectively. They accounted for 1.346–1.661%, 0.164–0.538%, and 0.021–0.068% of the exergy of oat straw, respectively. The O/C, H/C, and N/C atomic ratios varied in the ranges of 0.7042–0.7780 (10.480%), 1.4713–1.6000 (8.747%), and 0.0024–0.0254 (958.333%), respectively, whereas the correlation factors varied between 1.131 and 1.142 (0.973%). The exergy values of the three oat straws were between 20.325 and 21.065 MJ/kg. They were mainly determined by the correlation factors and the LHVs. A positive linear relationship between the exergy and LHV was observed. [ABSTRACT FROM PUBLISHER]

Natural variations in the stable isotope ratios of bioelements in bird feathers are being increasingly used by animal ecologists to investigate different aspects of bird life. However, to ensure reliability of the data, a critical and very delicate aspect is the preparatory phase (cleaning, drying and subsampling) and the proper analysis, mainly in relation to δ2 H and δ18 O, respectively, for the presence of exchangeable Hs and of nitrogen and sulphur in keratin., With respect to determination of the isotope ratios of C, N, O and H, in this work, we compare the cleaning mixture most commonly used in the literature (chloroform : methanol 2 : 1) with diethylether : methanol 2 : 1, which avoids the use of the carcinogenic solvent chloroform. We also compared oven-drying with air-drying of samples, as well as subsampling of feathers by cutting with surgical scissors or cryogenic pulverization. Finally, we investigated whether stable isotope ratios varied along the vane and between the rachis and vane., The different methods compared in the three preparatory stages showed no differences performance-wise and can therefore be used interchangeably. Variability in stable isotope ratios can be considerable, both along the vane and between rachis and vane, which is because their compositions register changes in diet, area and climate. However, in this specific study, when the parts of the feather closest to the calamus were removed, the delta values were clearly more homogeneous. Finally, we demonstrate that a casein with a known δ2 H value, although probably differing from keratin in the number of exchangeable Hs, can be used to normalize the δ2 H values of feathers, although only in the range of values close to that of the reference material. In determining δ18 O, the use of a longer gas chromatography- GC column, its frequent change and the use of a linear equation built with matrix match equivalent reference materials seems to reduce the drift of GC column performance due to the presence of nitrogen and the accumulation of sulphur. [ABSTRACT FROM AUTHOR]

H, C, and N NMR chemical shifts have been measured for 2-aminopyridine N-oxide ( 1), its eleven derivatives ( 2- 10, 13, 14), and 3-Cl and 3-Br substituted 4-nitropyridine N-oxides ( 11, 12). δ(N) of pyridine ring nitrogen in 2-acetylaminopyridine N-oxides are 5.9-11.5 ppm deshielded from those in 2-aminopyridine N-oxides. When amino and acetylamino substituents are in 4-position, δ(N) of ring nitrogen is 21.3 ppm deshielded in the acetylated derivative. The strong resonance interaction between 2-amino and 5-nitro groups reflects in the decrease of amino nitrogen shielding about 5.3-17.9 ppm. Also, H and C NMR spectral data are in agreement with N NMR results reflected as deshielded amino protons and carbons C-2 and C-5. The pyridine nitrogen chemical shift in all amino- and acetylamino derivatives vary between −101.2 and −126.7 ppm, which has been connected with the tautomeric balance in our earlier studies. [ABSTRACT FROM AUTHOR]

A new developing field of application for pressure swing adsorption (PSA) processes is the capture of CO to mitigate climate change, especially the separation of CO and H in a pre-combustion context. In this process scheme the conditions of the feed to the separation step, namely a pressure of 3.5 to 4.5 MPa and a CO fraction of around 40% are favorable for an adsorption based separation process and make PSA a promising technology. Among the commercial adsorbent materials, activated carbon is most suitable for this application. To evaluate the potential, to benchmark new materials, and for process development a sound basis of the activated carbon thermodynamic data is required, namely equilibrium adsorption isotherms of the relevant pure components and mixtures, Henry's constants and isosteric heats. In this work pure adsorption equilibria of CO, H and N on commercial activated carbon (AP3-60 from Chemviron, Germany) are measured using a Rubotherm Magnetic Suspension Balance (MSB) (Bochum, Germany) in a wide temperature and pressure range. The data is used to fit the temperature dependent parameters of Langmuir and Sips (Langmuir-Freundlich) isotherms and to determine the Henry's constants as well as isosteric heats. Based on this evaluation different methods to evaluate the data are compared and discussed. With the pure isotherm parameters of the Sips isotherm binary adsorption is predicted using an empirical binary Sips equation and ideal adsorbed solution theory (IAST). The results are compared to binary measurements in the same MSB applying a gravimetric-chromatographic method. [ABSTRACT FROM AUTHOR]

The mechanism proposed earlier for explanation of the furoxan ring formation in the nitrosation of dipotassium salts of 1-hydroxyimino-2,2-dinitro-1-R-ethanes with NaNO/AcOH was confirmed experimentally by determining the ionization constants of the dinitromethyl and oxime fragments in the starting dipotassium salt and by examining H, C, N, and N NMR and mass spectra of isomeric 3(4)-nitro-4(3)-R-furoxans with the N(5) and N(2) ring atoms, respectively, and 3,4-diarylfuroxan with both N-labeled ring atoms. A comparative analysis of the IR and Raman spectra of the N-labeled furoxan derivatives obtained and their unlabeled analogs allowed refinement of the literature data on interpretation of the vibrational spectra of furoxan derivatives. [ABSTRACT FROM AUTHOR]

Abstract: Chemical properties of coal which impact on gasification performance relate to those processes which do effect a change in chemical constitution, these in turn may lead to changes in physical properties such as particle size distribution and surface area of the coal. Turn-out samples obtained from a commercial-scale Sasol-Lurgi fixed-bed dry bottom (FBDB) gasifier were characterized to understand and interpret the internal chemical property behaviour and are discussed in relation to the residual C, H, N, S and O distribution profiles obtained. Thermodynamic equilibrium simulation of the organic and inorganic speciation behaviour occurring within a fixed-bed gasifier was modelled using the Fact-Sage simulation package, and used to support the measured ultimate analysis profile data obtained. The measured gasifier ultimate analysis profiles provided good insight into understanding the development of aromaticity of the char, expressed by the carbon:hydrogen ratio calculated on a mass basis. Equilibrium compositional profiles calculated for C, H, N, S and O provided discernment regarding the speciation and partitioning behaviour occurring within the fixed-bed-reactor. Fact-Sage thermodynamic equilibrium modeling of the gasifier related to the ultimate analysis results, was found to be useful in identifying an oxygen scavenging effect created by the mineral transformation behaviour occurring during reduction. It was found that oxygen-containing species such as Mg2Al4Si5O18 (corderite) and Fe2Al4Si5O18 (ferro-corderite) form within the reduction zone. It would appear that mineral composition is a more fundamental property than merely ash content in the gasification process, when viewed on an oxygen consumption basis. [Copyright &y& Elsevier]

The wealth of male decedents using census-linked probate records from 1892 and 1902 is examined for evidence on saving motives. This data presents an opportunity to examine wealth holding and saving motives in an environment devoid of many of the features that can affect modern retirement, consumption and saving decisions. Evidence is found supporting the existence of a strategic bequest motive. This result occurs after controlling for the possibility of the demand for children rising with the level of wealth as well as the potential contribution to wealth accumulation that children made in agricultural economies. These results also suggest that while the presence of a bequest motive was real and significant, its ultimate contribution to wealth accumulation was relatively modest when compared to the impact of variables such as occupational status and literacy. Moreover, there appears to be some evidence supporting a transition in saving motives away from bequest saving and towards greater life cycle saving. [ABSTRACT FROM AUTHOR]

Abstract: An attempt is made to study the existence of dynamical fluctuations of relativistic particles using the methods of modified multifractal moments, , and scaled factorial moments, , in terms of new scaled variable suggested by Bialas and Gazdzicki. For this purpose analyses of experimental and UrQMD data involving interactions of 28Si and 12C nuclei at with nuclear emulsion are used. The variation of and with in pseudorapidity phase space reveals power law behaviour. The values of slopes, and determined from the analyses of and moments are discussed. The generalized fractal dimensions, , determined from the above methods are found to decrease with the order of the moments, q, indicating multifractality in multiparticle production. It is also observed that the spectral function for heavier projectile is much broader than for lighter beam due to larger number of participating nucleons present in heavier projectile. [Copyright &y& Elsevier]

Abstract: Thoria is a promising matrix for the immobilisation of plutonium in either a burning or a conditioning strategy. The aim of this work is twofold: to study the impact of the addition of plutonium, simulated with cerium, on the physico-mechanical properties of thoria and to investigate the possibility of synthesising ceramics employing simple fabrication routes. Th1−x Ce x O2 powders with ceria concentrations from 0 to 75% were synthesised by the co-precipitation method. The properties of the powders, such as thermal and crystallisation behaviour, were determined as a function of ceria content and calcination temperature. (Th,Ce)O2 pellets containing up to 20% ceria were compacted from non-ground 675K calcined powder using a double repressing method. The pellets have densities of up to 0.98 TD and a homogeneous surface with well-distributed pores. The main mechanical properties, such as microhardness and fracture toughness, were also investigated as a function of ceria content. [Copyright &y& Elsevier]

The genes for the Variant Surface Glycoprotein (VSG) of Trypanosoma brucei are transcribed in telomeric expression sites (ESs). There are about 20 different ESs per trypanosome nucleus. Usually, only one is active at a time, but trypanosomes can switch the ES that is active at a low rate (<10−5 per cell per generation). To study activation and silencing of ESs, we have generated a line of T. brucei 427 with three ESs marked with a different drug resistance gene. We show that a selection with any combination of two of these drugs leads to an unstable double-resistant phenotype in which the two ESs containing the corresponding marker genes switch backward and forward at a very high rate (>10−1 per cell per generation). Unstable triple-resistant trypanosomes were not obtained. We conclude that the unstable rapid-switching state is a natural intermediate in ES switching. It only involves two ESs, whereas the other ESs are not expressed. Furthermore, we show that ‘inactive’ ESs can exist at several different stable levels of activation. Whereas, a ‘silent’ ES shows a low level of expression of promoter proximal sequences, the level of activation can be reversibly increased, leading to partially activated ESs. [Copyright &y& Elsevier]

The present study evaluates natural composition of Serbian roasted hazelnut skins (HS) with potential role in application as functional nutrient of various food products. Total phenols (TPC) and flavonoids contents (TFC) in HS extracts obtained with different ethanol concentrations (10%—I, 50%—II and 96%—III) and their antioxidant activities were investigated. The highest total phenols content (706.0 ± 9.7 mgGAE/gextract) was observed in 96% ethanol HS extract. Ethanol HS extracts showed very high antioxidant activity with effective concentrations (EC50) ranged between 0.052 and 0.066 mg/mL. The phenol and flavonoid content of roasted HS extracts I–III was determined by HPLC-ESI-MS/MS analyses. Contents of lipids, proteins, carbohydrates, metals, and C, H, N, S elements in roasted HS were also determined. Relatively high C/N, C/P and C/N/P ratios, rich metal contents and fatty acids composition indicated that hazelnut skin might be a good candidate for use as either human or fungal functional nutrient. In addition, possible application of phenolic HS extracts as UV booster was studied by recording UV spectra (220–440 nm) of 10 mg/L of HS extracts I–III combined with 10 mg/L of chemical sunscreen agent benzophenone-3 and in vitro sun protection factor (SPF) was calculated. [ABSTRACT FROM AUTHOR]

A steady state concentration of HSNO is obtained using a gaseous mixture of 1% NO and 0.1% H2S in Ne by supersonic expansion into a cavity through a pulsed valve at 25 °C. [ABSTRACT FROM AUTHOR]

Flash vacuum pyrolysis of MeOS(O)2N3 (caution: potentially hazardous and explosive) results in the formation of HNSO2 in the gas phase. [ABSTRACT FROM AUTHOR]

Single crystals of the title amidozincate of several centimeters in dimensions are grown under ammonothermal conditions in the cold temperature zone of an autoclave using Zn powder and CsNH2 in a 1:2 molar ratio (stainless steel autoclave, 523→≈423 K, 155 MPa, 12 h). [ABSTRACT FROM AUTHOR]

Compounds (IV) and (V) are characterized by single crystal XRD and UV/VIS spectroscopy. [ABSTRACT FROM AUTHOR]

Review: 102 refs. [ABSTRACT FROM AUTHOR]

Formation of [NH4][BH3NH2BH3] by metathesis reaction between Na(BH3NH2BH3) and NH4SCN in a 1:1 molar ratio in THF at -18 °C is monitored by 11B NMR spectroscopy. [ABSTRACT FROM AUTHOR]

Selective conversion of N2 into NH3 is achieved through plasmon-induced charge separation by a SrTiO3 photoelectrode loaded with Au nanoparticles and a Zr/ZrOx thin film. [ABSTRACT FROM AUTHOR]

Single crystals of ZnF2(NH3)3 (I) are prepared by ammonothermal reaction of ZnF2, Zn, NH4F, and NH3 (autoclave, 250 °C, 196 MPa). [ABSTRACT FROM AUTHOR]

Li4(NH2)3Cl is prepared by ball milling of a stoichiometric mixture of LiNH2 and LiCl (400 rpm, 5 h) followed by ball milling with LiH to form a composite. [ABSTRACT FROM AUTHOR]

CaNH shows a strong synergistic effect on Mn6N5 in catalyzing the decomposition of NH3. [ABSTRACT FROM AUTHOR]

[Fe(PO4)(N2H4)]n is prepared under hydrothermal conditions using an aqueous solution of FeCl2 and N2H2 to which KH2PO4 is added (autoclave, 433 K, 10 h). [ABSTRACT FROM AUTHOR]

Single crystals of (H3NOH)3PO4 are formed from a 1:3 molar mixture of H3PO4 and NH2OH upon cooling. [ABSTRACT FROM AUTHOR]

Electrical charging of graphitic g-C4N3 and g-C3N4 nanosheets is proposed as a strategy for high-capacity and electrocatalytically switchable H2 storage. [ABSTRACT FROM AUTHOR]

Single crystals of [Pu2(OH)2(NO3)6 (H2O)4]2·11H2O (I) and Pu2(OH)2(NO3)6 (H2O)4·2H2O (II) are obtained by evaporation of aqueous stock solutions of 25 mM 242Pu in 4 M HNO3. [ABSTRACT FROM AUTHOR]

Na[Al(NH2BH3)4] is obtained by ball milling of a NaAlH4-4AB (AB: NH3BH3) composite under the release of 4.5 wt.% of H2. [ABSTRACT FROM AUTHOR]

Single crystals of (NH4)2SnCl6 are obtained by thermal decomposition of SnCl4·5NH3 in the gas phase under a stream of gaseous NH3 (quartz tube, 298 °C, 6 h). [ABSTRACT FROM AUTHOR]

LiNH4(H2PO4)2 is prepared from an equimolar aqueous mixture of NH4H2PO4 and LiH2PO4 by slow evaporation at 25 °C. [ABSTRACT FROM AUTHOR]

Solvent- and halide-free ammine rare earth metal borohydrates Ln(BH4)3·nNH3 (Ln: Y, Gd, Dy; n = 7, 6, 5, 4, 2, 1) are synthesized by combined mechanochemistry and solvent-based metathesis reactions of LiBH4 and LnCl3 in the ratio of 3:1, followed by reaction of the produced Ln(BH4)3 with an excess of NH3 gas, yielding Ln(BH4)3·7NH3, that stepwise releases ammonia on thermal treatment. [ABSTRACT FROM AUTHOR]

Mechanical activation of a 1:4:1 molar mixture of Mg(NH2)2, LiH, and LiNH2 by ball milling under Ar (400 rpm, 20 h) results in a composite which is further used in dehydrogenation experiments using TG-DTA (140-400 °C) with mass spectrometric gas detection. [ABSTRACT FROM AUTHOR]

Cd(NH3)2 [B3O5(NH3)]2 is prepared by high-pressure reaction of a 1:3:4 molar mixture of CdO, B2O3, and 28% aq. [ABSTRACT FROM AUTHOR]

Single crystals (3 mm length) of Li4[Zn(NH2)4](NH2)2 are obtained from Li and Zn, (ratio of 1:4-1:5) in supercritical NH3 (autoclave, 158 MPa, 723 K). [ABSTRACT FROM AUTHOR]

Isotypic MH4P6N12 (M: Mg, Ca) compounds are prepared by high-pressure/high-temperature reactions of stoichiometric amounts of M3N2, HPN2, and P3N5 (multi-anvil press, 8 GPa, 1000 °C, 2 h). [ABSTRACT FROM AUTHOR]

The title compound, N2H4(BH3)2, is prepared from a mixture of freshly ground [N2H5][HSO4] and NaBH4 in THF (Ar-filled glovebox, round-bottom flask, 40 °C, 42-90 h, 87% yield). [ABSTRACT FROM AUTHOR]

The entitled Mn complex is obtained from the filtrate of an 8:4 molar mixture of Mn(O-Ac)2 and CAN in warm MeNO2 with an excess of AcOH (3 d, 40 % yield). [ABSTRACT FROM AUTHOR]

Single crystals of SrBa2(NH2)6 are obtained from the ammonothermal reaction of Ba and Sr (Ni alloy 718 autoclave, 180 MPa NH3, 573 K, 36 h). [ABSTRACT FROM AUTHOR]

The title γ-P4N6(NH) polymorph is obtained by high-temperature high-pressure synthesis using P3N5 and NH4Cl in the molar ratio of 4:1 (multianvil cell, 14 GPa, 1200 °C, 3 h). [ABSTRACT FROM AUTHOR]

Ca14As6C0.445N1.135 H4.915 and LiCa3As2H are obtained from a Ca/Li melt containing Ca, Li, As, C, CaH2, and Ca3N2 in a molar ratio of 7:7:1.4:0.4:0.4:0.4 (stainless steel crucibles, Ar, 1050 °C, 2 h; controlled cooling). [ABSTRACT FROM AUTHOR]