Molar Basis Research Articles

An experimental and modeling study on auto-ignition kinetics of ammonia/methanol mixtures at intermediate temperature and high pressure

A rapid compression machine (RCM) has been applied to measure the ignition delay times of NH3/CH3OH mixtures covering pressures of 20 and 40 bar, equivalence ratios of 0.5, 1.0 and 2.0, and temperatures between 845 and 1100 K. The measurements show that the NH3/CH3OH mixtures become more reactive with increasing methanol addition. Addition of merely 1% (molar basis) of CH3OH to NH3 lowers the ignition temperature around 100 K at 40 bar in comparison to pure NH3. The ignition delay is a complex function of fuel mixture and stoichiometry. For the 1% CH3OH mixture, the leaner mixtures are more reactive, while the reverse trend is found for mixtures with 5%, 20% and pure CH3OH. Analysis of the pressure profiles shows three distinct ignition modes for NH3/CH3OH mixtures, facilitated by the pre-ignition heat release from NH3 consumption. A detailed mechanism for ignition of NH3/CH3OH fuel blends has been developed, capable of reproducing the ignition behavior of mixtures with reasonable accuracy. A subset for amine / methanol interactions was established, with rate constants for the key reaction between NH2 and CH3OH calculated from ab initio theory. A sensitivity analysis indicates that the critical reactions during the auto-ignition process vary with the CH3OH mole fraction in the fuel. The ammonia chemistry, namely NH2 + NO, NH2 + NO2 and NH2 + HO2, is dominant for the mixture with 1% CH3OH, while the reactions related to CH3OH and H2O2 are more important for the 20% CH3OH mixture. The interaction between ammonia and methanol shows a more prominent effect on auto-ignition for mixtures with 5% CH3OH in fuel as compared to those with 1% and 20% CH3OH. According to the modeling results, methanol addition is found to enrich the O/H radical pool, consuming ammonia and promoting auto-ignition through different reaction pathways.

Effect of dietary phenylalanine levels on growth, hemato-biochemical composition and tyrosine replacement value for phenylalanine in stinging catfish Heteropneustes fossilis –Bloch 1974 fingerling

Two 10-week feeding experiments were conducted to determine the total aromatic amino acid requirement and tyrosine (Tyr) replacement value for phenylalanine (Phe) for fingerling Heteropneustes fossilis by feeding casein + gelatin based amino acid test diets [400 g/kg crude protein (CP); 17.90 MJ/ kg gross energy (GE)]. In experiment 1, Phe was determined by feeding six test diets containing graded levels of Phe (4.5–14.5 g/kg diet, as fed) with 6.0 g/kg Tyr fixed and fed in triplicate groups of 20 fish each in 60-L troughs fitted with continuous flow-through. Significantly (P < 0.05) highest live weight gain (LWG%), best-feed conversion ratio (FCR), highest protein efficiency ratio (PER) and body protein deposition (BPD) was reported at 10.5 g/kg dietary Phe with constant level of Tyr 6.0 g/kg fed group. Quadratic regression analysis of live weight gain, FCR, PER and BPD data indicated Phe requirement at 11.08, 10.75, 10.45 and 10.45 g/kg of diet, respectively. Based on the above results, Phe requirement of H. fossilis is recommended at 10.8 g/kg of diet. A second experiment under similar experimental design was conducted containing graded levels of Tyr (2.1–12.1 g/kg diet, as fed) with 10.8 g/kg Phe fixed in all the diets to determine the replacement value of Tyr for Phe. Significantly (P < 0.05) highest LWG%, best-FCR, PER and BPD values were obtained at 8.1 g/kg dietary tyrosine level. Quadratic regression analysis of LWG%, FCR, PER and BPD data indicated Tyr requirement at 8.7, 8.7, 8.05 and 8.05 g/kg of diet, respectively. The above results suggest that 8.4 g/kg Tyr, corresponding to 21.0 g/kg of protein would be useful for optimum growth of H. fossilis at fingerling stage and the replacement value of Tyr for Phe is 43.75% on weight and 39.89% on molar basis. Thus, the total aromatic amino acid requirement was recommended to be 19.2 g/kg of diet, corresponding to 48.0 g/kg of protein for optimum growth of H. fossilis.

Soot and PAH formation in high pressure spray pyrolysis of gasoline and diesel fuels

Time-resolved soot and PAH formation from gasoline and diesel spray pyrolysis are visualized and quantified using diffuse back illumination (DBI) and laser induced fluorescence (LIF) at 355 nm, respectively, in a constant-volume vessel at 60 bar from 1400 to 1700 K for up to 30 ms. The delay, maximum formation rate, and yield of soot and PAHs are compared across fuels and temperatures and correlated with the yield sooting indices on either the mass or mole basis. The delays generally decrease with increasing temperature, and the formation rates of both PAHs and soot generally increase with temperature. The apparent PAH-LIF yield may decrease with temperature due to PAH growth and conversion into larger species, signal trapping, and thermal quneching. Soot yield generally increases with temperature. The mass-based YSI correlates reasonably well with soot delay, but YSI does not correlate well with soot yield. The mass-based YSI is a more appropriate predictor of sooting propensity than the mole-based YSI.

Microemulsions: Breakthrough Electrolytes for Redox Flow Batteries.

Aqueous and non-aqueous redox flow batteries (RFBs) have limited energy and current densities, respectively, due to the nature of the electrolytes. New approaches to electrolyte design are needed to improve the performance of RFBs. In this work, we combined a highly conductive aqueous phase and an organic redox-active phase in a microemulsion to formulate a novel RFB electrolyte. As a proof-of-concept, we demonstrate an RFB using this microemulsion electrolyte with maximum current density of 17.5 mA·cm−2 with a 0.19 M posolyte and 0.09 M negolyte at a flow rate of only ∼2.5 ml·min−1, comparable to early vanadium electrolyte RFBs at similar flow rates on a per molar basis. The novel active negolyte component is an inexpensive oil-soluble vitamin (K3). By combining aqueous and organic phases, the solvent potential window and energy density may be increased without sacrificing current density and new redox couples may be accessed. Microemulsion electrolytes show great promise for improved performance and increased energy densities in aqueous RFBs but the path forward is complex. We end with discussion of areas that need work to achieve the potential of these electrolytes.

Volatile organic compound fluxes over a winter wheat field by PTR-Qi-TOF-MS and eddy covariance

Abstract. Volatile organic compounds (VOCs) contribute to air pollution through the formation of secondary aerosols and ozone and extend the lifetime of methane in the atmosphere. Tropospheric VOCs originate to 90 % from biogenic sources on a global scale, mainly from forests. Crops are also a potentially large yet poorly characterized source of VOCs (30 % of the VOC emissions in Europe, mostly oxygenated). In this study, we investigated VOC fluxes over a winter wheat field by eddy covariance using a PTR-Qi-TOF-MS with high sensitivity and mass resolution. The study took place near Paris over a 5-week period and included flowering, crop maturity and senescence. We found a total of 123 VOCs with fluxes 3 times above the detection limit. Methanol was the most emitted compound with an average flux of 63 µg m−2 h−1, representing about 52 % of summed VOC emissions on a molar basis (36 % on a mass basis). We also identified ethanol, acetone, acetaldehyde and dimethyl sulfide among the six most emitted compounds. The third most emitted VOC corresponded to the ion m/z 93.033. It was tentatively identified as furan (C6H4O), a compound not previously reported to be strongly emitted by crops. The average summed VOC emissions were about 173 ± 6 µg m2 h−1, while the average VOC depositions were about 109 ± 2 µg m−2 h−1 and hence 63 % of the VOC emissions on a mass basis. The net ecosystem flux of VOCs was an emission of 64 ± 6 µg m−2 h−1 (0.5 ± 0.05 nmol m−2 s−1). The most deposited VOCs were identified as hydroxyacetone, acetic acid and fragments of oxidized VOCs. Overall, our results reveal that wheat fields represent a non-negligible source and sink of VOCs to be considered in regional VOC budgets and underline the usefulness and limitations of eddy covariance measurements with a PTR-Qi-TOF-MS.

Hydrogen production from steam and dry reforming of methane-ethane-glycerol: A thermodynamic comparative analysis

Glycerol is produced as a by-product waste during the biodiesel manufacturing process. In recent researches, glycerol has been extensively studied for its potential to be converted into higher value-added compounds because it is renewable and bioavailable compound to reduce the high biodiesel production cost. As a result, various methods and technologies, such as steam reforming and dry reforming, were utilized to convert glycerol to higher value added products. The straightforward route of dry and steam reforming techniques uses carbon dioxide and other greenhouse gases to create added-value products like syngas, which may be considered renewable alternatives to fossil fuels as global CO2 emission issues get higher and near-uncontrollable. Therefore, this article presents a novel thermodynamic equilibrium analysis of steam and dry reforming with methane-ethane-glycerol mixture based on the total Gibbs free energy minimization method for hydrogen generation. Equilibrium product compositions were determined as a function of molar ratio between H2O/methane-ethane-glycerol (WMEG) from 1:1 to 12:1 and CO2/methane-ethane-glycerol (CMEG) from 1:1 to 12:1 for steam and dry reforming respectively, where the molar basis of the methane-ethane-glycerol mixture is 1:1:1. The reforming temperatures are ranged from 573 K to 1273 K at atmospheric pressure of 1 bar. The production trends of H2, CO, CO2, CH4 and C were compared between both reforming of glycerol. From to the result of the study, the optimal operating parameter for the highest hydrogen production was under steam reforming with WMEG of 3:1 at 1273 K and zero carbon deposition is achieved. In comparison with CO and CO2 production, dry reforming produced higher yields than steam reforming. Furthermore, a significant increment of hydrogen production was not observed at higher ratios of WMEG and CMEG. Steam reforming inhibited the carbon formation thermodynamically better than dry reforming.

Influence of co‐neutralization by sodium and zinc on the ethylene ionomer structure and properties

AbstractThis study investigates the properties and structure of poly(ethylene‐co‐methacrylic acid) (EMAA) ionomers co‐neutralized by zinc and sodium, and compares them with ionomers neutralized by a single metal: zinc (EMAA‐Zn) and sodium (EMAA‐Na). The bending stiffness and the degree of crystallization for the co‐neutralized ionomer (Na:Zn = ~1:1 on a molar basis) gives 16.5% and 9.8% increase compared to the simple average of their single cation counterparts. Such unusual properties are seen in mechanical, thermal, and rheological properties and water uptake rate in this study. Infrared spectra of the co‐neutralized ionomer shows changes at the carboxylate antisymmetric stretching band, which correspond to the formation of carboxylates bridging zinc and sodium ions. X‐ray scattering identified that the number density of ionic multiplets for the co‐neutralized ionomers are equivalent to EMAA‐Na and ~ 1.7 times higher than EMAA‐Zn. The fraction of side groups forming ionic multiplets, β, in co‐neutralized ionomers were 0.7–0.8, close to EMAA‐Na (1.0) and higher than EMAA‐Zn (0.3), indicating that sodium promote zinc to form ionic multiplets. The synergistic properties induced by co‐neutralization are ascribed not only to a formation of new ionic multiplets where both cations are included but also to the change in the number density of ionic multiplets.

Field-Scale Demonstration of PFAS Leachability Following In Situ Soil Stabilization

A field-scale validation is summarized comparing the efficacy of commercially available stabilization amendments with the objective of mitigating per- and polyfluoroalkyl substance (PFAS) leaching from aqueous film-forming foam (AFFF)-impacted source zones. The scope of this work included bench-scale testing to evaluate multiple amendments and application concentrations to mitigate PFAS leachability and the execution of field-scale soil mixing in an AFFF-impacted fire-training area with nearly 2.5 years of post-soil mixing monitoring to validate reductions in PFAS leachability. At the bench scale, several amendments were evaluated and the selection of two amendments for field-scale evaluation was informed: FLUORO-SORB Adsorbent (FS) and RemBind (RB). Five ∼28 m3 test pits (approximately 3 m wide by 3 m long by 3 m deep) were mixed at a site using conventional construction equipment. One control test pit (Test Pit 1) included Portland cement (PC) only (5% dry weight basis). The other four test pits (Test Pits 2 through 5) compared 5 and 10% ratios (dry weight basis) of FS and RB (also with PC). Five separate monitoring events included two to three sample cores collected from each test pit for United States Environmental Protection Agency (USEPA) Method 1315 leaching assessment. After 1 year, a mass balance for each test pit was attempted comparing the total PFAS soil mass before, during, and after leach testing. Bench-scale and field-scale data were in good agreement and demonstrated >99% decrease in total PFAS leachability (mass basis; >98% mole basis) as confirmed by the total oxidizable precursor assay, strongly supporting the chemical stabilization of PFAS.

Development of an Innovative Berberine Food-Grade Formulation with an Ameliorated Absorption: In Vitro Evidence Confirmed by Healthy Human Volunteers Pharmacokinetic Study.

Objective To evaluate in vitro solubility, bioaccessibility, and cytotoxic profile, together with a pharmacokinetic profile by oral administration to healthy volunteers of a novel food-grade berberine formulation (BBR-PP, i.e., berberine Phytosome®). Results An in vitro increase of solubility in simulated gastric and intestinal fluids and an improved bioaccessibility at intestinal level along with a lower cytotoxicity with respect to berberine were observed with BBR-PP. The pharmacokinetic profile of the oral administration to healthy volunteers confirmed that berberine Phytosome® significantly ameliorated berberine absorption, in comparison to unformulated berberine, without any observed side effects. The berberine plasma concentrations observed with both doses of BBR-PP were significantly higher than those seen after unformulated berberine administration, starting from 45 min (free berberine) and 30 min (total berberine). Furthermore, BBR-PP improved berberine bioavailability (AUC) was significantly higher, around 10 times on molar basis and with observed dose linearity, compared to the unformulated berberine. Conclusion These findings open new perspectives on the use of this healthy berberine formulation in metabolic discomforts.

Wide range temperature stability of palladium on ceria-praseodymia catalysts for complete methane oxidation

Catalytic oxidation is the most effective technology to control methane emissions from both mobile and stationary sources. Palladium-based materials are widely viewed as the most active catalysts for the methane abatement reaction, even though the high-temperature PdO/Pd transition is linked to a decrease in catalytic activity. Aimed at minimizing this phenomenon, this work compares the catalytic activity and the thermal stability of different Pd-impregnated cerium-praseodymium mixed oxides prepared via Solution Combustion Synthesis. Although the palladium deposition on pure ceria allows obtaining a highly active system, the introduction of praseodymium enhances the thermal stability of the catalyst in an extended temperature range. X-ray photoelectron spectra show that the presence of praseodymium retains Pd in a more oxidized form, thus stabilizing the high-temperature active phase. This effect, as evident from X-ray diffractograms and Raman analyses, was attributed to a strong interaction of palladium particles with praseodymium, thereby hindering their reduction to the metallic form. Moreover, Pr doping played a significant role during methane oxidation in the presence of 5% H2O, improving both activity and stability compared to Pd on pure ceria. On the whole, Pd/Ce90Pr10 (2 wt% palladium supported on a mixed oxide with a praseodymium content of 10% on a cerium-praseodymium molar basis) was found to be the most promising catalyst amongst the studied materials in both dry and wet conditions, benefitting from the synergistic effect of ceria and praseodymia in improving the Pd activity and stability.

Cell Culture Characterization of Prooxidative Chain-Transfer Agents as Novel Cytostatic Drugs.

Prooxidative therapy is a well-established concept in infectiology and parasitology, in which prooxidative drugs like artemisinin and metronidazole play a pivotal clinical role. Theoretical considerations and earlier studies have indicated that prooxidative therapy might also represent a promising strategy in oncology. Here, we have investigated a novel class of prooxidative drugs, namely chain-transfer agents, as cytostatic agents in a series of human tumor cell lines in vitro. We have found that different chain-transfer agents of the lipophilic thiol class (like dodecane-1-thiol) elicited half-maximal effective concentrations in the low micromolar range in SY5Y cells (human neuroblastoma), Hela cells (human cervical carcinoma), HEK293 cells (immortalized human kidney), MCF7 cells (human breast carcinoma), and C2C12 cells (mouse myoblast). In contrast, HepG2 cells (human hepatocellular carcinoma) were resistant to toxicity, presumably through their high detoxification capacity for thiol groups. Cytotoxicity was undiminished by hypoxic culture conditions, but substantially lowered after cellular differentiation. Compared to four disparate, clinically used reference compounds in vitro (doxorubicin, actinomycin D, 5-fluorouracil, and hydroxyurea), chain-transfer agents emerged as comparably potent on a molar basis and on a maximum-effect basis. Our results indicate that chain-transfer agents possess a promising baseline profile as cytostatic drugs and should be explored further for anti-tumor chemotherapy.

Biotransformation Potential of Cationic Surfactants in Fish Assessed with Rainbow Trout Liver S9 Fractions.

Biotransformation may substantially reduce the extent to which organic environmental contaminants accumulate in fish. Presently, however, relatively little is known regarding the biotransformation of ionized chemicals, including cationic surfactants, in aquatic organisms. To address this deficiency, a rainbow trout liver S9 substrate depletion assay (RT‐S9) was used to measure in vitro intrinsic clearance rates (CLint; ml min–1 g liver–1) for 22 cationic surfactants that differ with respect to alkyl chain length and degree of methylation on the charged nitrogen atom. None of the quaternary N,N,N‐trimethylalkylammonium compounds exhibited significant clearance. Rapid clearance was observed for N,N‐dimethylalkylamines, and slower rates of clearance were measured for N‐methylalkylamine analogs. Clearance rates for primary alkylamines were generally close to or below detectable levels. For the N‐methylalkylamines and N,N‐dimethylalkylamines, the highest CLint values were measured for C10–C12 homologs; substantially lower clearance rates were observed for homologs containing shorter or longer carbon chains. Based on its cofactor dependency, biotransformation of C12–N,N‐dimethylamine appears to involve one or more cytochrome P450–dependent reaction pathways, and sulfonation. On a molar basis, N‐demethylation metabolites accounted for up to 25% of the N,N‐dimethylalkylamines removed during the 2‐h assay, and up to 55% of the removed N‐methylalkylamines. These N‐demethylation products possess greater metabolic stability in the RT‐S9 assay than the parent structures from which they derive and may contribute to the overall risk of ionizable alkylamines. The results of these studies provide a set of consistently determined CLint values that may be extrapolated to whole trout to inform in silico bioaccumulation assessments. Environ Toxicol Chem 2021;40:3123–3136. © 2021 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.

A Novel Approach to Assess the Potency of Topical Corticosteroids.

The potencies of topical corticosteroid products have mainly been classified using clinical data but in some instances, the US Food and Drug Administration’s (FDA’s) vasoconstrictor assay (VCA) to assess the skin blanching response has also been used. However, the reported skin blanching response data were often based on a single visual reading and lack information on the dose (amount/quantity) or dose duration. Although several lists classifying potencies of various topical corticosteroid products have been published, the inherent potencies of topical corticosteroid raw materials used as active pharmaceutical ingredients (APIs) have not been investigated. The objective was to rank the inherent potencies of topical corticosteroid APIs and to standardize dosing such that the relevant compounds could be compared on a normalized molar basis. The potencies of clobetasol propionate, halcinonide, mometasone furoate, and fluocinolone acetonide were compared using the resulting Emax data following the fitting of the relevant response data to the Emax model where mometasone furoate > fluocinolone acetonide = clobetasol propionate > halcinonide. This ranking lists the respective inherent potencies of the APIs, which will facilitate the choice of a suitable candidate for incorporation into an appropriate topical corticosteroid product for a specific clinical indication.

Effect of senescence on biogenic volatile organic compound fluxes in wheat plants

Exchanges of biogenic volatile organic compounds (BVOC) between plants and the atmosphere are likely to vary, in amount and composition, between different plant species but also for a single plant during its development. However, the effect of plant development stages, including senescence, on BVOC exchanges remains poorly investigated, especially in the case of crop plants. We investigated the BVOC exchange patterns for wheat plants, the most grown crop species worldwide, during seed maturation, senescence and after harvest. Fluxes were measured online, in situ, at the plant scale by combining automated chambers and a Proton Transfer - Reaction - Quadrupole ion guide - Time of Flight - Mass Spectrometer (PTR-Qi-Tof-MS). The high resolution and sensitivity of this method enabled the measurement of a large mass spectrum of compounds emitted at very small amounts, allowing a precise characterization of BVOC exchanges. We found that the overall BVOC emissions increased twofold during the senescence stage compared to the maturation stage. Methanol was found to be the most emitted compound (49–60% of the overall flux on a molar basis) followed by acetone (7.5–8.2% of the overall flux on a molar basis) during each developmental stage investigated. Acetaldehyde was another major emitted compound contributing mainly during late senescence to the overall flux (9.7%). When normalized for temperature and light conditions, most BVOC emissions increased during senescence, showing a clear effect of senescence on BVOC exchanges. Chamber emissions were comparable to whole ecosystem fluxes measured at the same site by eddy covariance the previous year. The OH reactivity of the emitted compounds was evaluated based on known reaction rate constants and was the largest during the first senescence stage, peaking at 12 s−1 in the chambers. The results of this study show the need for considering plant phenology when computing BVOC emissions from crops.

Interaction of NH3 and NO under combustion conditions. Experimental flow reactor study and kinetic modeling simulation

The interaction between ammonia and NO under combustion conditions is analyzed in the present work, from both experimental and kinetic modelling points of view. An experimental systematic study of the influence of the main variables for the NH3NO interaction is made using a laboratory tubular flow reactor installation. Experiments are performed at atmospheric pressure and variables analyzed include: temperature in the 700–1500 K range, air stoichiometry, from pyrolysis to very oxidizing conditions, and the NH3/NO ratio, in the 0.7–3.5 range. Nitrogen and argon have been used as diluent gas. A literature reaction mechanism has been used to simulate the present experimental results and discuss the main findings. Reaction path analysis has allowed the identification of the reaction routes under the studied conditions. The simulations reflect the main experimental trends observed. Main results show that NO reduction by NH3 occurs at any conditions studied, but is more intense under oxygen excess conditions. Interactions of NH3 and NO proceeds in a molar basis with optimum conversions of NO of up to almost 100%.

Effect of air humidity and natural gas composition on swirl burner combustion under unstable conditions

Combustion instabilities are an undesired phenomenon in premix burners, leading to vibrations and potential flame problems such as lift-off or flashback. The combustion stability in a premix burner is highly sensitive to fuel composition and local environmental conditions. Consequently, this work presents the effect of air humidity and fuel composition on the degree of combustion instability in a swirl stabilized premix burner at atmospheric pressure, initiating in both unstable and stable states. The experimental setup consists of a swirl stabilized 20 kW burner with a square combustion section of 100 mm × 100 mm, with optical access to the reaction zone on three sides. Three types of fuel were evaluated: methane (CH4), CUSIANA (85% CH4; 10% C2H6; 5% C3H8), and propane (C3H8). Atmospheric humidity was emulated over a range from 0% to 5%, molar basis, the high point corresponding to the greatest atmospheric humidity. The degree of burner instability was characterized by the standard deviation of the pressure signal. It was found that atmospheric humidity can reduce combustion instability, affecting methane more significantly than propane at low air preheat temperature (315 K); at high preheat temperature, the water content was found to have no effect on combustion instability. The flame structure, i.e. shape and size, was similar for all fuel types at the same adiabatic flame and air preheat temperatures. Under unstable operating conditions, a similar flame shape and area of oscillation were found with the same resonant frequencies. This indicates that the variables characterizing thermoacoustic instability maintain similar values or proportions, regardless of the fuel type.

An oral lipidic native testosterone formulation that is absorbed independent of food.

ContextThere is no licensed oral native testosterone (NT) because of challenges in the formulation. Licensed oral formulations of the ester, testosterone undecanoate (TU), require a meal for absorption and generate supraphysiological dihydrotestosterone (DHT) levels.ObjectiveTo develop an oral NT formulation.Design and methodsA lipid-based formulation of native testosterone filled into soft-gelatin capsules at 40 mg per capsule was designed with 2 years of stability at ambient temperature. Pharmacokinetic comparison studies of this oral lipidic NT formulation to oral TU were conducted in dogs and hypogonadal men.ResultsIn dogs, 40 mg NT was well absorbed under fasted conditions whereas 40 mg TU required a high-fat meal: for NT, the mean fed/fasted AUC ratio was 1.63 and for TU 7.05. In hypogonadal men, fed and fasted NT had similar pharmacokinetics: Cmax mean 26.5 vs 30.4 nmol/L (769 vs 882 ng/dL), AUC0–10 h 87 vs 88.6 h nmol/L. NT (fed state) showed a testosterone AUC increase of 45% between 120 and 200 mg, and NT 200 mg gave a similar mean AUC0–10 h to TU 80 mg: 87 vs 64.8 h nmol/L. Serum TU levels were variable and on a molar basis were ~ten-fold higher than serum testosterone levels after TU 80 mg fed. The DHT: testosterone AUC0–10 h ratio was more physiological for NT than TU being 0.19 vs 0.36. There were no emerging safety concerns with NT.ConclusionThis novel oral lipidic native testosterone formulation has potential advantages over oral TU of dosing independently of food and a lower risk of supraphysiological DHT levels. Significance statement There is no licensed oral testosterone because of challenges in formulation, and the oral formulations of the ester, testosterone undecanoate, require a fatty meal for absorption and generate supraphysiological dihydrotestosterone levels. We have overcome the design challenges and formulated an oral native testosterone that can be taken with or without food and provides physiological levels of testosterone and dihydrotestosterone in hypogonadal men. This formulation, DITEST, has the potential advantage of being oral for patients who do not tolerate injections and less risk of adverse events that might theoretically be associated with elevated dihydrotestosterone levels. Future studies will need to define the dosing regimen for replacement in hypogonadal men.

Extending the ability of cyclic carbonates for extracting BTEX to challenging low aromatic content naphtha: the designer solvent role at process scale

Aromatic separation from naphthas with low aromatic content is still a challenging issue. Cyclic carbonates have been recently reported as tunable CO2-derived organic solvents in this field, synergistically reducing CO2 emissions. In this work, an extended database of cyclic carbonates was created. COSMO-RS showed the designer capacity of cyclic carbonates by their functionalization, allowing to cover wide ranges of extractive properties. N-based and cyclic substituents revealed improved selectivities; conversely, cyclic functionalization enhances aromatic distribution ratios. Cyclic carbonates were implemented in a process simulator using COSMO/Aspen methodology, evaluating their aromatic/aliphatic separation performance at process scale to guide the design of these emerging solvents. Moving from molar basis (COSMO) to mass basis (COSMO/Aspen), it was found a reduced number of cyclic carbonates with potential in the studied separation. High purity BTEX fraction is effectively separated with selectivities over 15 and optimized by aromatic distribution ratios, drawing leading cyclic carbonates’ structures.

A Compendium of Methods for Determining the Exergy Balance Terms Applied to Reciprocating Internal Combustion Engines

Abstract Exergy analysis of the reciprocating internal combustion (IC) engines is studied by estimating various input and output energy transfer parameters concerning a dead state reference. Exergy terms such as fuel input, work output, cooling, and exhaust gas are measured and are set into the exergy balance equation to determine the amount of loss or destruction. Exergy destructions are found in many forms such as combustion (entropy generation), cylinder wall, friction, mixing, blow-by, and others. These exergy terms have been estimated by considering various factors such as engine type, fuel type, environmental condition, and others. In this article, the different methods employed in estimating these exergy terms have been reviewed. It attempts to make a compendium of these evaluation methods and segregates them under individual exergy terms with necessary descriptions. The fuel input measurement is mostly based on Gibb's free energy and the lower heating value, whereas its higher heating value is used during the fuel exergy calculation on a molar basis. The work output of the engines is estimated either from the crankshaft or by analyzing the cylinder pressure and volume. The exergy transfer with cooling medium and exhaust gas depends on the temperature of the gas. The maximum achievable engine performance is quantified by estimating the exergy efficiency. This piece of study will not only provide plenty of information on exergy evaluation methods of IC engines but will also allow future researchers to adopt the appropriate one.

In vivo study of the bioavailability and metabolic profile of (poly)phenols after sous-vide artichoke consumption

Artichokes are a rich source of (poly)phenols, mainly caffeoylquinic acids, but little is known about their bioavailability from this source. This study investigated the absorption, metabolism and excretion of (poly)phenols after sous-vide artichoke consumption (5776 µmol of (poly)phenols) by healthy volunteers. Seventy-six (poly)phenol metabolites were identified by UHPLC-MS/MS using authentic standards, including acyl-quinic acids plus C6–C3, C6–C1, C6–C2, C6–C1–N, C6–C0 metabolites, and their phase-II conjugates. The major metabolites were 3ʹ-methoxy-4ʹ-hydroxycinnamic acid, 3ʹ-methoxycinnamic acid-4ʹ-sulfate, and 4ʹ-hydroxycinnamic acid-3ʹ-sulfate, which appeared early in plasma (Tmax < 4 h); plus 3-(3ʹ-methoxy-4ʹ-hydroxyphenyl)propanoic acid, 3-(4ʹ-methoxyphenyl)propanoic acid-3ʹ-glucuronide, 3-(3ʹ-hydroxyphenyl) propanoic acid and hippuric acids, which appeared later (Tmax > 6 h). The 24 h urinary recovery averaged 8.9% (molar basis) of the (poly)phenols consumed. Hepatic beta-oxidation of 3ʹ,4ʹ-dihydroxycinnamic acid and methylated conjugates occurred, but was limited (<0.04%). 3ʹ-Methylation exceeded 4ʹ-methylation and interindividual variability was high, especially for gut microbial metabolites (up to 168-fold).