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Chlorosis at leaf margins is a typical symptom of potassium (K) deficiency, but inappropriate application of K with other nutrients often masks symptoms of K deficiency. A two-year field experiment was conducted to measure the interactive effects of N and K on leaf photosynthesis and dry matter accumulation and the resulting growth dilution effect on K concentration and leaf K deficiency symptoms. N application aggravated the imbalance of N and K nutrients and further exacerbated K deficiency symptoms under K limitation. Synergistic effects of N and K promoted plant growth, amplified the growth dilution effect, and reduced the critical K concentration in leaves. Using 90% of the maximum shoot biomass as a threshold, the critical K concentration was 0.72% at the recommended N (N180) fertilization level. The critical K concentration increased by 62.5% owing to the reduced biomass under insufficient N (N90) supply. In contrast, high N (N270) reduced the critical K concentration (0.64%), accelerating chlorophyll decomposition and exacerbating K deficiency symptoms. The basis of changing the critical K concentration by magnifying growth dilution effect was the functional synergistic effect of N and K on photosynthetic characteristics. Under insufficient N, the low maximum carboxylation rate (Vcmax) limited the net photosynthetic rate (An) and necessitated more K to maintain high CO2 transmission capacity, to improve the total conductance gtot /Vcmax ratio. High N supply increased gtot and Vcmax, possibly mitigating the effect of K reduction on photosynthesis. In conclusion, it is unwise to judge K status of plants only by K concentration without accounting for crop mass (or dilution effect), critical K concentration and deficiency symptoms are affected by N fertilization, and the synergistic effect of N and K on leaf photosynthesis is the foundation of maximal growth of plants under diverse critical K concentrations.

To study the effects of different diluents on the propagation characteristics of H2/CO/air mixture turbulent premixed flames, a series of experiments were carried out in a turbulent premixed flame experimental system. The effects of turbulence intensity (0.49–1.31 m/s), dilution gas content (10%, 20%, and 30%), hydrogen fraction (50%, 70%, and 90%), and equivalence ratio (0.6, 0.8, and 1.0) on the turbulent premixed flame were studied. The results show that with the increase in hydrogen fraction or turbulence intensity or equivalence ratio, the ST and ut increase at the same radius. Compared with N2 dilution, CO2 dilution showed a more obvious inhibition effect on ST. With the increase of Ka, ST;35mm/u’ gradually decreased, and the extent of ST;35mm/u’ decrease gradually became smaller. As the intensity of turbulence increases or the hydrogen fraction increases, the slope of ST,35mm/u’ with Da/Le gradually decreases. In the turbulence intensity range of this experiment, the ut,35mm/μl under nitrogen dilution condition has a larger floating range. The growth rate of ut,35mm/μl at a low equivalence ratio is significantly higher than that at a high equivalence ratio.

The effects of different mole fractions of hydrogen and carbon dioxide on the combustion characteristics of a premixed methane–air mixture are experimentally and numerically investigated. The laminar burning velocity of hydrogen-methane-carbon dioxide-air mixture was measured using the spherically expanding flame method at the initial temperature and pressure of 283 K and 0.1 MPa, respectively. Additionally, numerical analysis is conducted under steady 1D laminar flow conditions to investigate the adiabatic flame temperature, dominant elementary reactions, and NO formation. The measured velocities correspond with those estimated numerically. The results show that increasing the carbon dioxide mole fraction decreases the laminar burning velocity, attributed to the carbon dioxide dilution, which decreases the thermal diffusivity and flame temperature. Conversely, the velocity increases with the thermal diffusivity as the hydrogen mole fraction increases. Moreover, the hydrogen addition leads to chain-branching reactions that produce active H, O, and OH radicals via the oxidation of hydrocarbons, which is the rate-determining reaction. Furthermore, an increase in the mole fractions of hydrogen and carbon dioxide decreases the NO production amount.

The administration of lithium chloride (LiCl) for cardiac output (CO) measurement via a peripheral instead of a central vein has been described previously as a valid alternative route in pigs and dogs. The aim of the study was to compare CO measurements after administration of LiCl using two peripheral veins, cephalic or jugular, in goats. Ten adult, female, experimental goats undergoing bilateral stifle arthrotomy were recruited for the study. Paired CO measurements were taken two minutes apart during stable conditions in isoflurane-anaesthetised goats. Forty-two paired CO measurements were taken in total, and the median (range) of paired CO measurement per goat were 4.5 (3–6). The mean (SD) CO using the cephalic and jugular vein for injection of LiCl was 5.28 (1.29) L min−1 and 5.20 (1.24) L min−1 respectively. The Bland-Altman analysis showed an acceptable agreement with a mean bias of 1.33% with limits of agreement (LoA) of −18.43 to 21.09%. The percentage of error was 25%. The four-quadrant plot analysis showed a poor agreement (71%) between the two routes. The polar plot showed a poor trending ability. An 86% inclusion rate (18/21 points) was reached with a ± 35° radial sector size. The findings revealed that the agreement between the two routes is not as precise as the authors expected, however the results are comparable with studies published previously.

This paper presents experimentally determined laminar burning speeds (SL) of premixed methane/oxygen/nitrogen mixtures at sub-atmospheric conditions obtained by using the constant-pressure spherica...

Traditional soybean (Glycine max L.) breeding has improved seed yield in high-input agricultural systems, under high nitrogen (N), phosphorus (P) and potassium (K) supply. The seed yield improvements under non-P supply and the seed protein and mineral content dilution by yield improvement were evaluated in 18 soybean cultivars released from 1995 to 2016 in south-east China. Soybean varieties were grown under rainfed conditions in the field under 0 and 35 kg P ha−1 in four sites: Dafang and Shiqian in the growing season of 2017 and Dafang and Puding in the 2018 season. The seed yield, seed protein content and nine seed nutrition concentration were examined. Soybean seed yield increased with the year of release at rates of 5.5–6.7 g m−2 year−1 under 35 kg P ha−1 and 3.9–4.8 g m−2 year−1 under non-P supply in the four experiments. The increase resulted from increases in the number of filled-pods and total seed number rather than from single seed weight and number of seeds per pod. Seed protein content and seed nutrition concentration has not changed with the year of release under 0 and 35 kg P ha−1. Grain yield was positively correlated with the seed Fe concentration. The cultivar superiority of seed yield, seed P, Zn and Ca concentration was negatively correlated with their static stability coefficient. Traditional soybean breeding increased yield under both P and non-P supply, without affecting seed protein content and mineral concentrations. A trade-off between high seed yield and seed P, Zn and Ca concentration and their stability under different environments was shown.

Compositional modification engineering was designed to simultaneously reduce the sintering temperature and improve the dielectric properties of BaTa2V2O11 via in-situ adjusting the V5+/Ta5+ molar ratio. A series of BaTa2-xV2+xO11 ceramics, fabricated by a solid-state reaction method, were characterized for structural evolution and dielectric properties variations. In-situ adjusting V5+/Ta5+ molar ratio significantly lowered the sintering temperature of BaTa2V2O11 and prominently improved the temperature stability of resonance frequency which is explained by the dielectric dilution theory. Competitive microwave dielectric properties with er = 11.5–25.9, Q × f = 22,172–42,660 GHz, and τf = 42.4–74.6 ppm/oC were achieved in the BaTa2-xV2+xO11 ceramics sintered at 620–840 oC. All the results indicate that the molar ratio of V5+ is primarily responsible for improving the densification behavior and dielectric characteristics of BaTa2-xV2+xO11, which in turn increases the appropriateness in further practical applications.

A new method of preparation of aqueous electrolyte baths for electrochemical deposition of nickel targets for medical accelerators is presented. It starts with fast dissolution of metallic Ni powder in a HNO3-free solvent. Such obtained raw solution does not require additional treatment aimed to removal nitrates, such as the acid evaporation and Ni salt precipitation-dissolution. It is used directly for preparation of the nickel plating baths after dilution with water, setting up pH value and after possible addition of H3BO3. The pH of the baths ranges from alkaline to acidic. Deposition of 95% of ca. 50 mg of Ni dissolved in the bath takes ca. 3.5 h for the alkaline electrolyte while for the acidic solution it requires ca. 7 h. The Ni deposits obtained from the acidic bath are physically and chemically more stable and possess smoother and crack-free surfaces as compared to the coatings deposited from the alkaline bath. A method of estimation of concentration of H2O2 in the electrolytic bath is also proposed.

Understanding the processes controlling dissolved reactive phosphorus (DRP) loss in tile-drained systems is essential to better define critical source areas and inform nutrient and conservation practice recommendations. Concentration-discharge (C-Q) relationships have been used to infer solute sources, reactivity, proximity, and transport mechanisms governing solute fluxes. In this study, we compare DRP loads and flow-weighted mean DRP (FDRP) concentrations from P source and sink soils at an annual and event scale, and use power law analysis coupled with index-based approaches in order to identify the predominant DRP C-Q behavior in these soils at a daily and event scale. Results indicate that, in general, P source soils consistently lost higher DRP loads and exhibited greater FDRP concentrations when compared to P sink soils when examined at both annual and event scales. At the daily scale, C-Q patterns were linked to the soil P status whereby a chemostatic (b = 1) and dilution (b

In this paper, the flow field characteristics of Oblique Detonation Waves (ODWs) induced by a finite wedge under argon dilution are studied by solving the Euler equations with a detailed chemical model of hydrogen and air. First, the effects of the expansion waves, argon concentration, geometric parameters, and Mach number on the ODW are discussed. The results show that the changes of these parameters may make the oblique detonation not be initiated. Then, the ODW initiation criterion of the finite wedge is summarized, as the characteristic length of the induction zone LC and the characteristic length of the oblique wedge LW meet the condition LC/LW

Optimization of process parameters for direct laser metal deposition of WC (88 wt%) and Co (12 wt%) mixed powder on SS304 substrate was carried out to obtain minimum dilution. The effect of process parameters on clad geometric elements was expressed through polynomial relations. A mathematical expression for dilution was developed in terms of clad geometric elements and then verified with experimentally obtained dilution. The regression analysis for each geometric element and dilution was also studied. To obtain an optimized set of process parameters four recently developed optimization algorithms were used, which was then followed by a confirmation test. Bonobo Optimizer algorithm was fast during the search for the globally optimum solution. A detailed macroscopic, microstructural, thermo-cycle and XRD analysis for the confirmed optimized run was carried out along with the comparison study. The hardness behaviour of clad tracks was also studied by comparing it with that of the substrate.

Densities of aqueous solutions of the strong electrolytes sodium perchlorate, potassium perchlorate, and potassium chloride have been measured by vibrating-tube densimetry at 5 K intervals over the temperature range 293.15 ≤ T (K) ≤ 343.15 up to near-saturation concentrations (for NaClO4 and KClO4) or to about 2 mol·kg–1 (for KCl) at 0.1 MPa pressure. Particular attention was paid to solute purity and solution composition. The densities were used to calculate the corresponding apparent molar volumes, Vϕ, which considerably extend and improve the quality of the volumetric database for these salts, especially with respect to temperature. Where comparisons were possible, the present Vϕ results agreed well with most literature data, with the significant exception of NaClO4(aq) at higher temperatures. The Vϕ values were extrapolated to infinite dilution using an extended Redlich–Rosenfeld–Meyer equation to yield the standard state partial molar volumes (V2o). A combination of these values with relevant literature data and a well-established extra-thermodynamic assumption was used to estimate the standard molar volumes, V2o(ion), of several key monovalent ions as functions of temperature. These values appear to be more reliable than existing estimates based on older data, and will be useful for determining volumes of other ions in aqueous solution.

Synthesizing and studying the properties of nanomaterials based on layered molybdenum disulfide, often face a need for rapid elemental analysis and prompt return of the material to the customer. Sometimes, nanoparticles of molybdenum disulfide are to be modified with metal compounds to improve the catalytic or magnetic properties of the material. We propose a method for rapid X-ray fluorescence determination of molybdenum and cobalt in the range of 10 – 50% in such compounds using a bulk method without dilution. Analytical signals were measured at the wavelengths of MoKα and CoKα lines using a VRA-30 spectrometer (Carl Zeiss, Germany; X-ray tube with Rh anode). The metal content was calculated using the derived coupling equations. The determination error ranges within ±2.7% (abs.) and 1.4% (abs.) for Mo and Co, respectively. Correctness of the method was confirmed for a batch of synthesized compounds by comparison of the results obtained with the data of XRF analysis using the dilution method traditionally used in the laboratory. The proposed rapid method provides simplification of the procedure and more than 4-fold shortening of analysis in time, the sample being preserved and can be used for further research.

Objective The present study aims at deciphering the nature of the water structure in two drugs at ultra high dilution (HD) by Laser Raman Spectroscopy. Method Two drugs like Sulphur and Natrum mur and their three high dilutions 30cH, 200cH and 1000cH were selected for the study. The 30cH means dilution 1060 with mechanical agitation in 30 steps.Raman spectra of the drugs and their medium (90%ethanol)were obtained in the wave number region of 2600-3800 cm-1. The intensity ratio at vibration frequencies between 3220 and 3420 (R1) and that between 3620 and 3420 (R2) were calculated for each HD as well as the control. Results Raman spectra show differences in intensities in different HD’s and their control in the stretching vibrations of CH and OH groups. The three HD’s of each drug show inverse relationship with respect to the R1 values. However, for R2 the relationship of HD’s for each drug is positive. Conclusion R1 provides information about the relative number of OH groups with strong and weak hydrogen bonds. R2 suggests the relative number of OH groups with broken and weak hydrogen bonds. Judged from R1 values the lower is the rank of HD, the stronger is the H-bond of the OH groups. In the light of R2 values the higher is the HD rank the more abundant is the free OH groups. So, hydrogen bond strength and free OH groups together make an effective HD rank relating to Sulphur and Natrum mur.

Key points Multibreath imaging to estimate regional gas mixing efficiency is superior to intensity-based single-breath ventilation markers, as it is capable of revealing minute but essential measures of ventilation heterogeneity which may be sensitive to subclinical alterations in the early stages of both obstructive and restrictive respiratory disorders. Large-scale convective stratification of ventilation in central-to-peripheral directions is the dominant feature of observed ventilation heterogeneity when imaging a heavy/less diffusive xenon gas mixture; smaller-scale patchiness, probably originating from asymmetric lung function at bronchial airway branching due to the interaction of convective and diffusive flows, is the dominant feature when imaging a lighter/more diffusive helium gas mixture. Since detecting low regional ventilation is crucial for characterizing diseased lungs, our results suggest that dilution with natural abundance helium and imaging at higher lung volumes seem advisable when imaging with hyperpolarized 129 Xe; this will allow the imaging gas to reach slow-filling and/or non-dependent lung regions, which might otherwise be impossible to distinguish from total ventilation shunt regions. The ability to differentiate these regions from those of total shunt is worse with typical single-breath imaging techniques. Abstract The mixing of freshly inhaled gas with gas already present in the lung can be directly assessed with heretofore unachievable precision via magnetic resonance imaging of signal build-up resulting from multiple wash-ins of a hyperpolarized (HP) gas. Here, we used normoxic HP 3 He and 129 Xe mixtures to study regional ventilation at different spatial scales in five healthy mechanically ventilated supine rabbits at two different inspired volumes. To decouple the respective effects of density and diffusion rates on ventilation heterogeneity, two additional studies were performed: one in which 3 He was diluted with an equal fraction of natural abundance xenon, and one in which 129 Xe was diluted with an equal fraction of 4 He. We observed systematic differences in the spatial scale of specific ventilation heterogeneity between HP 3 He and 129 Xe. We found that large-scale, central-to-peripheral convective ventilation inhomogeneity is the dominant cause of observed heterogeneity when breathing a normoxic xenon gas mixture. In contrast, small-scale ventilation heterogeneity in the form of patchiness, probably originating from asymmetric lung function at bronchial airway branching due to interactions between convective and diffusive flows, is the dominant feature when breathing a normoxic helium gas mixture, for which the critical zone occurs more proximally and at an imageable spatial scale. We also showed that the existence of particular underventilated non-dependent lung regions when breathing a heavy gas mixture is the result of the density of that mixture - rather than, for example, its diffusion rate or viscosity. Finally, we showed that gravity-dependent ventilation heterogeneity becomes substantially more uniform at higher inspired volumes for xenon gas mixtures compared to helium mixtures.

The duration of photofermentative hydrogen production from sugar-based nutrients is limited by gradual acidification caused by the production of organic acids, leading to suboptimal pH. To address this issue, a custom pH control system was built and installed on a 20 L tubular photobioreactor, and operated under outdoor conditions. Long-term, single-stage hydrogen production from molasses was achieved using the purple non-sulfur bacterium, Rhodobacter capsulatus. The run lasted for 48 days, the longest duration achieved in a tubular photobioreactor on molasses as the only feed. pH was maintained close to its optimum value. High-purity hydrogen (above 90% by mole, on average) and near-complete conversion of sucrose was observed. The highest hydrogen productivity was 0.69 molH2/(m3.h). On the other hand, hydrogen production was observed to cease after periods of activity. Production resumed after dilution followed by artificial illumination, indicating that the production activity could be recovered during prolonged runs.

Quantitative characteristics of the immediate environment of ions in aqueous ZnCl2 solutions are determined by XRD in a wide range of concentrations. In a saturated solution, the Zn2+ ion coordinates two water molecules at a distance of 0.208 nm. The ions form an associate containing one Cl– ion at a distance of 0.225 nm and two Cl– ions at a distance of 0.380 nm. As the concentration decreases, the Cl– ions leave the associate, starting with more distant ions and proceeding with the ion of the contact ion pair. As a result, the ion pairs are destroyed and Zn2+ and Cl– ions undergo independent hydration. The number of water molecules in the coordination sphere of Zn2+ ions increases up to six within a distance of 0.212 nm. Dilution naturally increases the number of water molecules in the anion′s hydration sphere at an average distance of 0.312 nm and in the cation′s second coordination sphere at an average distance of 0.424 nm.

Ultrasound-assisted extraction and direct analysis were compared with total digestion for magnesium determination in beer samples by flame atomic absorption spectrometry. The method for total digestion used concentrated nitric acid under plate heating. In optimized instrumental conditions, validation of the analytical method was promoted, with good linear range (0.06 to 0.5 mg L�1), low limits of detection and quantification (0.04 and 0.12 �g g�1, respectively), good precision, relative standard deviation (RSD) less than 3.4%, and accuracy (recovery levels of 91.5 to 99.0%). The characteristic concentration (C0) was 9 �g L�1. The extraction procedure was performed in a 1:1 nitric acid solution for 55 min in an ultrasonic bath at 60 �C, while the direct analysis involved a dilution of the samples in a 2% v/v nitric acid solution. The different sample preparation methods were applied to 13 beer samples and at a 95% confidence level, no significant differences were observed. Thus, direct analysis proved to be more suitable for quality control routines of beer samples in the industry.

Field experiments of nitrogen (N) treatment at five different application rates (0, 75, 150, 225, and 300 kg ha−1) were conducted under pot-seedling mechanical transplanting (PMT) in 2018 and 2019. Two high-quality and high-yielding hybrids of indica rice, Huiliangyou 898 and Y Liangyou 900, were used in this study. The N nutrition index (NNI) and accumulated N deficit (Nand), used to assess the N nutrition status in real-time, were calculated for the indica cultivars under PMT with a critical nitrogen concentration (Nc) dilution model based on shoot dry matter (DM) during the whole rice growth stage. The relationships between NNI and Nand with relative yield (RY) were determined, and accurate N application schemes were developed for hybrids indica rice under PMT. The results indicated that high application rate of N-fertilizer significantly increased the concentrations of shoot DM and N in aboveground organs during the observed stages in the two cultivars for two years (P

The spark-ignition features of premixed H2 under Ar–O2 atmospheres are essential for the development of high-efficiency and zero-emission Argon Power Cycle engines. Therefore, constant-volume combustion vessel experiments are conducted at an initial temperature of 287 K, initial pressures of 0.1, 0.3, and 0.5 MPa, with diluents of Ar/N2/CO2. Excess oxygen ratio, defined as the ratio of O2 supplied to the O2 needed for stoichiometric combustion, ranges from 1.0 to 4.7. Dilution ratios, defined as the molar fractions of diluents in the diluent-O2 mixture, were separately 70%, 79%, and 88%. Results show that both high dilution ratios and high excess oxygen ratios lengthen the flame-initiation periods. With excess oxygen ratio of 3.3, when Ar dilution ratio increases from 79% to 88%, the flame-initiation period rises by a factor of five to ten. With Ar diluent ratio of 79%, when excess oxygen ratio increases from 2.5 to 4.7, the flame-initiation period rises from under 10 ms to over 60 ms. Both the application of Ar as the diluent and high initial pressures extend the flammability limits. With Ar dilution ratio of 79% and pressure no less than 0.3 MPa, the flammability limit on excess oxygen ratio is over 4.7. Furthermore, Ar can additionally shorten the flame-initiation periods. At 0.1 MPa, excess oxygen ratio of 2.5, when diluents are respectively Ar, N2, and CO2, the flame-initiation periods are 10, 19, and 41 ms. The research reveals that a spark-ignition Argon Power Cycle engine running with ultra-lean and highly diluted mixtures may be feasible.

An assessment of the efficiency and safety of the formaldehyde decontamination process containing solid waste of wood-chip boards by method of medium-temperature dry pyrolysis at the installation developed by the authors was evaluated. Sawdust of chip boards and coke ash residue after their pyrolysis were subjected to biological examination. The test objects were Daphnia magna Straus, algae Scenedesmus quadricauda and luminescent bacteria. It was revealed that pyrolysis of these wastes at the proposed plant will reduce the load on the hydrosphere and reduce the ratio of dilution of water extracts by more than half. Analysis of the composition of pyrolysis gases showed that the mass concentration of nitrogen oxides and carbon in the air of the working zone does not exceed the MPC of the working zone and MPC of settlements. The conclusion on environmental safety of the process of pyrolysis of formaldehyde-containing solid wastes at the proposed installation is made.

The objective of this study was to evaluate the effects of AgNPs on Artemia salina and Allium cepa, evaluating the influence of the dilution solutions on the particle behavior. The AgNPs were synthesized by chemical reduction of AgNO3 (3 and 5 mmol L−1) with sodium borohydride and stabilized with PVA (polyvinyl alcohol) and CMC (sodium carboxymethyl cellulose). The toxicity of AgNPs was evaluated in Artemia salina (mortality) using Meyer’s solution as a diluent and in Allium cepa (chromosomal aberrations) using reconstituted hard water. AgNPs showed characteristic molecular absorption bands. Particles with CMC presented hydrodynamic radius between 4 and 102 nm and with PVA between 7 and 46 nm. The studied dispersions were toxic to A. salina species. Meyer’s solution, used as dilution water in the test, caused precipitation of Ag+ and also caused changes in CMC-stabilized AgNPs, changing the shape of the nanoparticles by depositing precipitates on their surface. These changes make the results of toxicity difficult to interpret. AgNPs stabilized with PVA remained unchanged. AgNPs affected cell division and caused the appearance of chromosomal aberrations on A. cepa. Higher numbers of chromosomal aberrations occurred in dispersions with smaller particle diameters (AgNPs3-PVA and AgNPs5-PVA, without dilution). In the studied conditions the dispersions were toxic to the tested organisms, the concentrations of precursors and the type of stabilizer used influenced the particle size and toxicity. In the test with A. cepa, the reconstituted hard water did not cause changes in the dispersions of AgNPs, whereas for A. salina the Meyer solution promoted aggregation of the particles and precipitation, in the dispersions stabilized with CMC, thus changing the samples.

The article presents studies on the extraction of iron from chloride solutions with aliphatic alcohols, ketones, and their mixtures. Dilution of 1-octanol with an inert aromatic diluent to a concen...

The aim of the study was to investigate the potential of microalgal cultivation on anaerobic liquid digestate as a growth medium. The two methods of liquid digestate treatment including centrifugation and distillation and the two algal strains (Chlorella vulgaris and Arthrospira platensis) were compared. Additionally, the volume of the liquid digestate used to prepare the culture medium constituted from 10 to 50% of the medium volume. The study demonstrated that the highest C. vulgaris and A. platensis biomass productions of 2490 mg TS/L and 2990 mg/L, respectively, were obtained by adding 50% of distilled digestate to a growth medium. Regarding centrifuged liquid digestate, only 10% dilution was required to obtain the maximum final biomass concentration. A. platensis removed 81.1% and 66.4% of the total nitrogen from medium prepared on distilled and centrifuged digestate, respectively, while C. vulgaris ensured 64.1% and 47.1% of removal, respectively. The phosphorus removal from both culture media was higher than 94.2% with A. platensis, while it was 70.4% from distilled and 87.4% from centrifuged media with C. vulgaris. The study confirmed a great potential of microalgal biomass production on anaerobic liquid digestate with a high treatment efficiency of digestate.

This article presents the results of initial thermodynamic analysis of possible direct carbon black (CB) plasma synthesis from the carbonaceous wastes. Equilibrium concentration of components for plasma pyrolysis of the wood-based wastes, rice husk, and recycled plastic in the temperature range 800–3000 K was determined. The specific power consumption for the plasma synthesis process has been calculated for various types of carbonaceous wastes, taking into consideration the dilution of the mixture with plasma and carrier gases, which allows optimizing the parameters of the plasma reactor. The data obtained could be used for the engineering of plasma systems for CB production from investigated carbonaceous wastes.

The present study has numerically investigated the Moderate or Intense Low oxygen Dilution (MILD) combustion regime, combustion processes and NO formation characteristics of the highly CO-rich syngas counterflow nonpremixed flames. To realistically predict the flame properties of the highly CO-rich syngas, the chemistry is represented by the modified GRI 3.0 mechanism. Computations are performed to precisely analyze the flame structure, NO formation rate, and EINO of each NO sub-mechanism. Numerical results reveal that the hydrogen enrichment and oxygen augmentation substantially influence the NO emission characteristics and the dominant NO production route in the CO-rich syngas nonpremixed flames under MILD and high temperature combustion regimes. It is found that the most dominant NO production routes are the NNH path for the lowest oxygen level (3%) and the thermal mechanism for the highest O2 condition (21%). For the intermediate oxygen level (9%), the most dominant NO production routes are the NNH route for the hydrogen fraction up to 5%, the CO2 path for the hydrogen fraction range from 5% to 10% and the thermal mechanism for the hydrogen fraction higher than 10%, respectively. To evaluate the contribution of the specific reaction on EINO the sensitivity coefficients are precisely analyzed for NO formation processes with the dominance of NNH/CO2/Thermal mechanism under the highly CO-rich syngas flames.

The monitoring and controlling of pH is important when preparing solutions for ophthalmic administration. In the case of povidone‐iodine, dilution in an appropriate buffer is needed to improve its ...

The effects of inert gas (i.e., He, Ar, and N2) and ignition position on flame dynamics in a half-open duct with an aspect-ratio of 10 are analyzed for hydrogen/air mixtures with constant laminar burning velocity SL. The results indicate that hydrodynamic and thermo-diffusive instabilities dominate flame propagations with ignition at the right-half part of the duct, while Rayleigh–Taylor instability dominates with ignition at the left-half part of the duct. The flame-sound interaction results in the periodic pressure oscillations. Due to decreased instability, the He-diluted flame exhibits a weaker sensitivity of explosion parameters to the ignition position. The maximum pressure Pmax is dominated by different mechanisms depending on the ignition position. Although constant SL is used, Pmax for the worst case with N2 dilution is two times that with He dilution, demonstrating the considerable effect of flame instabilities. Finally, a chemical kinetic calculation is performed to clarify the flame stabilities.

To better understand Moderate or intense low-oxygen dilution (MILD) combustion, numerical simulations of pulverized coal MILD combustion with different inlet velocities and oxygen concentrations are presented in this work. The flow and chemical reaction characteristics are analyzed and the MILD performance is determined by the Damkohler number, Da, and the circulation coefficient, K υ , with different oxygen concentrations and inlet velocities. Results show that the oxygen concentration has a more pronounced impact on the chemical reaction, and the inlet velocity has a more pronounced impact on the flow time scale. The K υ values are found increasing with the oxygen concentrations, which is caused by the decreased total amount of flue gas. Modified schematic diagram of combustion regimes is presented based on the analysis. The Da number increases with the increase of oxygen concentration. This is because, on the one hand, the increase in oxygen concentration leads to the decrease in the inlet velocity. On the other hand, the oxygen concentration intensifies the chemical reaction. This indicates that, with the increasing oxygen concentration, the larger K υ or the smaller Da is required to establish the MILD combustion. If the burner structure is not changed, increasing the oxygen concentration will reduce flue gas entrainment and aggravate chemical reactions, which is not conducive to the MILD coal combustion.

Propylene is used for manufacturing commonly used raw materials and synthetic materials for petrochemical processes. However, it is a volatile and flammable material that poses fire and explosion risks. Nitrogen is inexpensive and can lower the propylene explosion limit because of the dilution effect when used as an inert gas. This study measures the explosion limit, minimum oxygen concentration (MOC), explosion pressure, explosion pressure rise rate, and deflagration index (Kg) values for propylene and nitrogen at 25 °C. Results showed that the lower explosion limit of the explosion range did not significantly change with an increase in pressure from 0.10 MPa to 0.25 MPa; however, the upper explosion limit increased significantly. Furthermore, the MOC decreased as pressure increased at 25 °C, while both the maximum explosion pressure and maximum explosion pressure rise rate increased, thereby increasing the explosion risk. The risk of propylene was predicted by the Kg values determined using the maximum explosion pressure rise rate and volume based on the experimental data. Therefore, through this study, we provide basic data on safety references for preventing fire and explosion accidents.

Hardfacing is done to increase the service life of structural components. Hardfacing is widely done in nuclear and petrochemical industries, mining and sugar refineries. Hardfacing is done on farming equipment to extend their service life as they are prone to impact, abrasion and corrosion. Generally, Ni-base, Co-base and Fe-base alloys are used for hardfacings. Among them, Ni-base alloys are preferred to Co-base and Fe-base alloys as these alloys can retain its hardness even at the elevated temperatures. Colmonoy alloys are predominantly used in nuclear reactor as the dose rate of these alloys is 1/265th that of Co-base alloys. Plasma Transferred Arc (PTA), Gas Tungsten Arc (GTA) and Laser are the major hardfacing processes. The hardfacing process governs the four major aspects of the coating, viz. microstructure, substrate dilution, wear and mechanical properties. This paper provides an in-depth understanding of various research works carried out on Ni alloy hardfacings by different processes on different substrates in those four domains. The outcome of this paper would be beneficial to present and future researchers on Ni alloy hardfacings and also to many hardfacing industries.

This paper presents optimization of process parameters in micro-plasma transferred arc deposition (µ-PTAD) process for cobalt-based alloy. Pilot experiments were conducted to find feasible range of values of six important process parameters, followed by 27 main experiments varying three process parameters of µ-PTAD for single-layer single track deposition. Deposition height, deposition width and percentage of dilution were measured as well as predicted using the regression model by varying three process parameters as micro-plasma power, travel-speed of nozzle and deposition powder feed rate. Percentage errors were also computed between measured values and predicted values. Microstructural analysis, elemental composition analysis using energy dispersive X-ray spectroscopy (EDS and measurement of micro hardness values were also done for deposition materials. Results of microstructural and EDS analysis revealed that deposition of Cobalt-based alloy consist of two-phase matrix namely Cobalt-rich matrix and carbides (Cr23C6, Cr7C3 and W2C) -phase matrix. Micro-hardness analysis revealed that the values of micro-hardness increases with decrease in micro-plasma power. This above work proves that Cobalt-based alloy deposition using µ-PTAD process has a competence to extend an economical and suitable explanation for good quality deposition for various industrial applications.

The effect of the dilution of a synthesis gas with nitrogen on the activity, selectivity and productivity of a Fischer–Tropsch reactor with a fixed bed of granular catalyst during synthesis on a pilot plant of a full cycle for the conversion of natural gas into synthetic oil is studied experimentally. Experimental data are presented that were obtained at different contents of nitrogen in the synthesis gas: up to 2, 50, and 70%. Analysis of the experimental data shows that diluting the synthesis gas contributes to an increase in the selectivity to C5+, and a decrease in the selectivity to methane. A drop in the reactor’s productivity observed upon the dilution of synthesis gas can be compensated for by increasing the consumption of synthesis gas. The negative effect of decrease in the pressure of FT synthesis from 2 to 1.5 and 1.0 MPa on the catalytic FT synthesis performed on a twice-diluted synthesis gas at a synthesis gas space velocity of 4000 h–1 is demonstrated.

In this study a procedure based on liquid chromatography (LC) and dynamic reaction cell inductively coupled plasma mass spectrometry (DRC ICP-MS), coupled with ultrasonic nebulization, for chromium speciation in rice was reported. Chromium (Cr) containing species, including Cr(III) and Cr(VI), were well separated by reversed phase HPLC with a C18 column as the stationary phase and a solution containing 0.5 mmol L−1 tetrabutyl ammonium phosphate (TBAP), 0.1 mmol L−1 EDTA and 2% (v/v) methanol (pH 6.9) as the mobile phase using isocratic elution. The chromatographic separation was complete in 4.5 min. Ammonia gas was employed as the reactive gas in the DRC to minimize spectral interference due to 40Ar12C+ and 35Cl16OH+ and 40Ar13C+ and 35Cl18O+ ions on the signal of 52Cr+ and 53Cr+, respectively. The detection limits were in the range 0.011–0.012 ng Cr mL−1. To verify the accuracy, the developed procedure was applied on a certified reference material (NIST SRM 1573a Tomato Leaves) wherein the sum of the concentrations of individual species agreed with the total certified concentration of Cr. Species were extracted using microwave heating with 1% (v/v) HF and 2 mmol L−1 EDTA. After ensuring the accuracy, this procedure has been applied to determine various Cr compounds present in rice and rice cereal. Supernatants were injected directly into the LC-ICP-MS system after dilution. The spike recovery was in the range of 95–105% and precision between sample replicates was better than 5% for all determinations. The LC-ICP-MS results showed satisfactory agreement with the total Cr concentrations obtained by ICP-MS analysis. Both Cr(III) and Cr(VI) were present in the samples analyzed. An unknown Cr compound was found in all the rice samples analyzed.

A thermodynamic analysis of the oxygen solutions in the carbon-containing Ni–Co melts is performed. The equilibrium constants of the reaction of carbon with oxygen, the activity coefficients at infinite dilution, and interaction parameters for melts differing in composition are determined at 1873 K. The dependences of the oxygen solubility in the nickel–cobalt melts on the cobalt and carbon contents are calculated. The contents of carbon monoxide (CO) and dioxide (CO2) in the gas phase over the melts are calculated.

Studies of emission factors from biomass burning using aircraft data complement the results of lab studies and extend them to conditions of immense hot conflagrations. A new theoretical development of plume theory for multiple tracers is developed after examining aircraft samples. We illustrate and discuss emissions relationships for 422 individual samples from many forest fire plumes in the Western USA. Samples are from two NASA investigations: ARCTAS (Arctic Research of the Composition of the Troposphere from Aircraft and Satellites) and SEAC4RS (Studies of Emissions and Atmospheric Composition, Clouds and Climate Coupling by Regional Surveys). This work provides sample-by-sample enhancement ratios (EnRs) for 23 gases and particulate properties. Many EnRs provide candidates for emission ratios (ERs, corresponding to the EnR at the source) when the origin and degree of transformation is understood. From these, emission factors (EFs) can be estimated, provided the fuel dry mass consumed is known or can be estimated using the carbon mass budget approach. This analysis requires understanding the interplay of mixing of the plume with surrounding air. Some initial examples emphasize that measured Ctot=CO2+CO in a fire plume does not necessarily describe the emissions of the total carbon liberated in the flames, Cburn. Rather, it represents Ctot=Cburn+Cbkgd, which includes possibly varying background concentrations for entrained air. Consequently, we present a simple theoretical description for plume entrainment for multiple tracers from the flame tops to hundreds of kilometers downwind and illustrate some intrinsic linear behaviors. The analysis suggests a mixed-effects regression emission technique (MERET), which can eliminate occasional strong biases associated with the commonly used normalized excess mixing ratio (NEMR) method. MERET splits Ctot to reveal Cburn by exploiting the fact that Cburn and all tracers respond linearly to dilution, while each tracer has consistent EnR behavior (slope of tracer concentration with respect to Cburn). The two effects are separable. Two or three or preferably more emission indicators are required as a minimum; here we used eight. In summary, MERET allows a fine spatial resolution (EnRs for individual observations) and comparison of similar plumes that are distant in time and space. Alkene ratios provide us with an approximate photochemical timescale. This allows discrimination and definition, by fire situation, of ERs, allowing us to estimate emission factors.

The presence of hydrogen sulfide (H2S) in biogas negatively affects human health and corrodes metal. Therefore, the removal of H2S from biogas before using is an essential requirement in many cases. Recently, biotrickling filters (BTFs) have been widely applied to the treatment of H2S on both laboratory and industrial scales. However, BTFs method also has some drawbacks such as low mass transfer efficiency, clogging the bed filter due to further elemental sulfur (S) excess accumulation, and biogas dilution. This paper reviews the recent development of aerobic BTF systems and solutions for those limitations during the H2S oxidation process in biogas. In addition, the factors affecting H2S removal efficiency, including sulfur-oxidizing bacteria, biofilm, packing material, pH, dissolved oxygen (DO), empty bed retention time (EBRT), ingredients of nutrients for the growth of bacteria, trickling liquid and gas velocity, are also discussed. Finally, the current strength of research in the field of H2S removal in biogas using BTF and its future prospects are also suggested. Some of highest elimination capacity (EC) of 78.57 g H2S/m3h, 144 g H2S/m3h, 228.6 g H2S/m3h were obtained from previous experiments.

Reliable ignition of reactant mixtures containing combustion products is important to the function of many practical combustion devices. Prior work has considered the influence of CO2 on ignition delay times and laminar flame speeds. This work examines the effects of dilution with CO2 on forced ignition and development of ignition kernels in CH4/air mixtures. Ignition kernels were initiated by a high voltage spark discharge in CH4/air/diluent mixtures with a bulk velocity of 5 m/s and with 0.7 ≤ Φ ≤ 0.8. Ignition probabilities and kernel growth rates were determined from radiation intensity measurements collected using a Telops MS-IR FAST infrared camera. Nitrogen was used as an inert in a subset of conditions to facilitate identifying changes in chemistry associated with dilution by CO2. Chemistry effects of diluents on ignition were isolated by examining undiluted, N2 diluted, and CO2 diluted flows with equivalent adiabatic flame temperatures. Dilution with CO2 reduced the probability of ignition relative to undiluted and N2 diluted conditions with the same adiabatic flame temperature. Ignition kernels diluted with CO2 also tended to be smaller than those initiated in both undiluted and N2 diluted mixtures, with reduced growth rates.

Introduction. Dental gel is one of the modern dosage forms with optimal biopharmaceutical properties for the treatment and prevention of oral diseases An isoquinoline alkaloid berberine is the promising active substance with antibacterial and anti-inflammatory effect, capable of forming stable dispersed systems with gel-forming components. It is noteworthy that, despite the pronounced antimicrobial activity of the alkaloid berberine, there is currently no dental dosage form with this component on the pharmaceutical market, and therefore research in this direction is of great interest.Aim. Selection of the optimal technology for obtaining dental gel with berberine for the treatment of oral diseases.Materials and methods. Berberine bisulfate (manufactured by CJSC «Vifitech», Obolensk, Moscow region, RF), poloxamers P407 and P338 (EP, USP/N; BASF, Germany), propylene glycol (USP; BASF, Germany), sodium chloride (Sigma-Aldrich, Germany, Cat. No. S9888), mucin type II from a pig stomach (Sigma-Aldrich, Germany, Cat. No. M2378). In the development of the composition and technology for the preparation of gels, a magnetic stirrer with a temperature control function (C-MAG HS 7 from IKA, Germany) was used. Gels were prepared by the «hot method» and «cold method».Results and discussion. The production of the gel by the «hot method» provided a uniform dosage form. The obtained pH value is within the range of optimal diapason. Measurement of the specific peel force of the model gel sample showed pronounced mucoadhesive properties, which indicates that there is no need to adjust this parameter by introducing additional components into the formulation. The spectroscopic method is applicable for the analysis of berberine gel. It has been found that a significant dilution of the reference substance sample is required to develop an identification procedure.Conclusion. The production of a sample of the dosage form by the «hot method» is optimal, which is probably due to the effect of solubilization and better distribution of the active substance in the base.

In biodiesel-fueled compression-ignition (CI) engines, dilution by unburned biodiesel has been found to have adverse effects on the boundary lubrication properties of additives in fully formulated engine lubricants. Such dilution of engine lubricants could be even more pronounced for CI engines running on higher blend concentrations of biodiesel. Given the nanoscopic nature of the interaction, this study seeks to determine the nano-tribological properties of an engine lubricant additive (e.g., zinc dialkyldithiophosphate (ZDDP)) when diluted with a fatty acid methyl ester (e.g., methyl oleate). Using lateral force microscopy (LFM) together with a fluid imaging technique, the lowest nanoscopic friction forces and coefficient of friction values (0.068–0.085) were measured for ZDDP when diluted with 70 vol% of methyl oleate. These values are also observed to be lower than those measured for neat ZDDP and neat methyl oleate, respectively, under similar conditions. Subsequently, interpreting the data with the Eyring thermal activation energy approach, it could then be elucidated that the lower frictional losses observed for the contact lubricated with this volumetric mixture are a result of the lower potential energy barrier and activation energy required to initiate sliding. These energy values are approximated to be 2.6% and 28.9% (respectively) lower than that of the contact lubricated with neat ZDDP. It was also found that the mixture, at this volumetric concentration, possesses the highest possible pressure activation energy (load-carrying capacity) along with the lowest possible shear activation energy (shearing), potentially indicating optimum tribological conditions for boundary lubrication. Thus, the findings of this study suggest that an optimum concentration threshold exists in which a synergistic nano-tribological interaction between additives and fatty acid methyl esters can be attained, potentially reducing boundary frictional losses of lubricated conjunctions. Such findings could prove to be essential in effectively formulating synergistic additive concentrations for engine lubricants used in biodiesel-fueled CI engines.

C2H4/N2O has recently been proposed as a promising monopropellant for hydrazine replacement. In this work, the auto-ignition capability of argon diluted C2H4/N2O was experimentally investigated firstly in a rapid compression machine by detecting the light emission and the pressure evolution profiles. The auto-ignition boundary temperature which separates the non-ignition and successful ignition cases was then determined and modeled as a function of pressure and mixture composition. Results show that the auto-ignition temperature decreases with the increase of pressure and increases with the argon dilution fraction and fuel oxidizer ratio. In addition, for successful auto-ignition cases, the ignition delay times were measured and used to validate several recently developed kinetic mechanisms. A mechanism was developed and showed good agreement with the measured ignition delay time as well as the auto-ignition boundary temperature at all test conditions. Finally, the auto-ignition boundary temperatures at practical rocket engine conditions (without dilution) were numerically predicted at various pressure and fuel oxidizer ratio conditions. The model is of merit for designing the cooling system and the local flow residence time to reduce the risk of fuel line explosion and the resonance acoustic induced combustion instability in practical rocket engine.

Denitrification and dissimilatory nitrate reduction to ammonium (DNRA) are two microbial processes competing for nitrate and organic carbon (COD). Their competition has great implications for nitrogen loss, conservation, and greenhouse gas emissions. Nevertheless, a comprehensive and mechanistic understanding of the governing factors for this competition is still lacking. We applied the resource-ratio theory and verified it with competition experiments of denitrification and DNRA reported in the literature. Based on this theory, we revealed how COD/N ratio, influent resource concentrations, dilution rate, and stoichiometric and kinetic parameters individually and collectively define the boundaries for different competition outcomes in continuous cultures. The influent COD/N ratio alone did not drive competition outcome as the boundary COD/N ratio for different competition outcomes changed significantly with influent resource concentrations. The stoichiometry of the two processes was determinative for the boundaries, whereas the affinity for the resources (Ks), maximum specific growth rate (μmax) of the two species and the dilution rate had significant impacts as well but mainly at low influent resource concentrations (e.g.

Objective In patients with severe hyperthyroidism unable to tolerate oral antithyroid therapy, diluted thiamazole infusion solutions (dose 120–240 mg) are administered by continuous infusion over 24 hours. Information about the type of diluent and compatibility/stability of the ready-to-administer thiamazole preparation is missing in the summary of product characteristics of the injection concentrate marketed in Germany. We studied the in-use stability of diluted infusion solutions over 24 hours. Methods Thiamazol 40 mg inject. Henning was diluted in prefilled polyolefin infusion bags containing 250 mL 0.9% sodium chloride (NaCl) infusion solution and kept for 24 hours at room temperature and diffuse room light. Content of the diluted infusion solutions (0.48 and 0.96 mg/mL) was analysed every 4 hours over the course of 24 hours by reversed-phase high-performance liquid chromatography. pH was measured after 0, 12 and 24 hours. The infusion bags were regularly inspected for visible particles. Subvisible particles were measured by particle counting. Results Thiamazole infusion solutions of the nominal concentrations 0.48 and 0.96 mg/mL in 0.9% NaCl diluent, kept at room temperature under diffuse room light, are physicochemically stable over a period of at least 24 hours. No evidence of colour change, particle formation or pH change was observed throughout the observation period. Conclusion Dilution of 120 or 240 mg doses of licensed thiamazole injection concentrate with 0.9% NaCl infusion solution in prefilled polyolefin containers is recommendable for continuous infusion over 24 hours in the treatment of thyrotoxicosis.

The numerical simulation was conducted to investigate the coupling effects of H2 and CO2 on the laminar flame speed and reaction pathways of the biogas-hydrogen mixtures. The same proportions of H2 and CO2 were considered in the study. The dilution effects, chemical effects and thermal effects of H2 and CO2 were isolated, while the contributions of different effects were also calculated to identify the dominating factor. The results show that H radical pool plays the important role in the variation of laminar flame speed of biogas-hydrogen mixture. The coupling dilution effects of H2 and CO2 lead to the considerable decrease of H radical and dominate the decreased laminar flame speed. The H2 chemical effects improve R84 (OH + H2 = H2O + H) and R3 (O + H2 = H + OH) quite effectively, which results in the reduced dropping trends of H radical and laminar flame speed from BG60H40 to BG40H60. The CO2 chemical effects suppress the major H radical production reactions of R84, R3, R99 (OH + CO = H + CO2) and R10 (O + CH3 = H + CH2O) more apparently at the fuel-rich condition, while importance of major consumption reactions (R53: H + CH4 = CH3+H2, R52: H + CH3(+M) = CH4(+M) and R58: H + CH2O = HCO + H2) are higher at the fuel-rich condition. This dominates the more evident decrease of H radical and laminar flame speed at the fuel-rich condition. Based on the ROP analysis, R3, R46 (H + HO2 = 2OH), R52, R84, R99 and R158 (2CH3(+M) = C2H6(+M)) have the major contributions on the chemistry transition caused by the coupling effects of H2 and CO2. The decreased contribution of R158 and R99 indicate the weakened CH4-related chemistry while the increased contributions of R3, R46, R52 and R84 indicate the improved H2-related chemistry in the biogas-hydrogen flame. Furthermore, coupling effects of H2 and CO2 or H2/CO2-related chemistry can be monitored by the contribution variations of R84 and R99 on the OH radical concentration.

The synthetic effect of H2O on the combustion characteristics of coal char is complicated due to its thermal (high volumetric heat capacity), chemical, and dilution (thereby low oxygen concentration) effects. To assess the impact of these factors on the carbon consumption process, we conduct a quantitative study on the net effect of H2O gasification through experimental and kinetic research. The experiment research is performed at 1773 K in a high-temperature drop tube furnace. The thermal effects of H2O are stripped off the net effect by introducing Ar into the bulk gas to neutralize its high heat capacity. We assess the chemical effects of gasification (gasification endothermicity, and its additional carbon consumption) for a 100 µm coal char particle reacting in environments of varying O2, H2O, and Ar using a self-developed char burning kinetics model. The relative contributions of H2O gasification and oxidation to carbon consumption are also discussed. Results indicate that the reduced carbon consumption through the negative effect of gasification (e.g., thermal effects and the gasification endothermicity) exceeds the additional carbon consumption from gasification reaction in the early combustion stages (

The environmental behavior of perfluorinated alkyl acids (PFAA) and their precursors was investigated in lake Tyrifjorden, downstream a factory producing paper products coated with per- and polyfluorinated alkyl substances (PFAS). Low water concentrations (max 0.18 ng L–1 linear perfluorooctanesulfonic acid, L-PFOS) compared to biota (mean 149 μg kg–1 L-PFOS in perch livers) resulted in high bioaccumulation factors (L-PFOS BAFPerch liver: 8.05 × 105–5.14 × 106). Sediment concentrations were high, particularly for the PFOS precursor SAmPAP diester (max 1 872 μg kg–1). Biota-sediment accumulation factors (L-PFOS BSAFPerch liver: 22–559) were comparable to elsewhere, and concentrations of PFAA precursors and long chained PFAA in biota were positively correlated to the ratio of carbon isotopes (13C/12C), indicating positive correlations to dietary intake of benthic organisms. The sum fluorine from targeted analyses accounted for 54% of the extractable organic fluorine in sediment, and 9–108% in biota. This, and high trophic magnification factors (TMF, 3.7–9.3 for L-PFOS), suggests that hydrophobic precursors in sediments undergo transformation and are a main source of PFAA accumulation in top predator fish. Due to the combination of water exchange and dilution, transformation of larger hydrophobic precursors in sediments can be a source to PFAA, some of which are normally associated with uptake from water. ACS AuthorChoice with CC-BY license.

The effect of syngas dilution with nitrogen on the activity, selectivity and capacity of the Fischer–Tropsch reactor with a fixed granulated catalyst bed was studied during the synthesis at the integrated pilot plant for conversion of natural gas to syncrude. Experimental data were obtained at different nitrogen content in syngas: up to 2, 50 and 70 %. The analysis of experimental data shows that the dilution of syngas increases the selectivity to C5+ and decreases the selectivity to methane. The decrease in the reactor capacity observed upon dilution of syngas can be compensated by increasing the syngas flow rate. A decrease in the pressure of the Fischer–Tropsch synthesis from 2 to 1.5 and 1.0 MPa was shown to exert a detrimental effect on the catalytic performance of the process carried out with a twofold dilution of syngas at its hourly space velocity of 4000 h–1.

Expansion of the works on the synthesis and study of the structure of new intercalation compounds based on molybdenum disulfide (MD)with various organic molecules inclusions in the layered structures, entails the necessity of developing methods for rapid analysis of those compounds for molybdenum content. We developed a rapid method of RF analysis of such compounds using in bulk method in the range of 28 – 50% Mo content. Analytical signals were measured for Mo K α line on a VRA-30 spectrometer («Karl Zeiss», Jena Germany, X-ray tube with Rh-anode operated in the mode of 35 kV, 15 mA). The molybdenum content is calculated using the derived constraint equation, the error of determination is ±2.5% Mo (abs.). In contrast to the traditional methods of external standard method with dilution used in the laboratory practice, the proposed method provides a satisfactory accuracy and reduces the duration of analysis from ~ 100 to ~ 20 min, the sample material being kept safe for further studies. Correctness of the method was confirmed for the batch of compounds by comparison of the obtained results and the data of XRF analysis with the dilution procedure.