carbon chain length
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Materials ◽  
2021 ◽  
Vol 15 (1) ◽  
pp. 142
Bartłomiej Rogalewicz ◽  
Tomasz Maniecki ◽  
Radosław Ciesielski ◽  
Agnieszka Czylkowska

In one of our previously published articles, we reported the synthesis, spectroscopic, thermal, and catalytic properties of four new M(II) acetate (where M = Co, Ni, Cu, Zn) complexes with imidazole. Presented compounds exhibited activity in the reaction on catalytic oxidation of styrene. In this study we have synthesized and investigated properties of analogous compounds, however using formates or propionates of mentioned metal cations instead of acetates. Such an approach allowed us to draw valuable conclusions concerning the relationship between the carbon chain length and catalytic activity, which is an important factor for catalyst modeling. Synthesized compounds have been thoroughly investigated using appropriate analytic techniques: AAS (Atomic Absorption Spectrometry), FTIR (Fourier-Transform Infrared Spectroscopy), and TGA (Thermogravimetric Analysis). Catalytic properties have been studied under the same previous conditions, using GC-FID (GC-chromatograph equipped with FID detector).

2021 ◽  
Vol 10 (4) ◽  
pp. 206-214
E. B. Shustov ◽  
A. V. Bunjat ◽  
A. G. Platonova ◽  
O. M. Spasenkova ◽  
N. V. Kirillova ◽  

Introduction. Non-alcoholic fatty liver disease (NAFLD) is the most common liver disease in the world. Non-alcoholic steatohepatitis (NASH), a clinically progressive morphological form of NAFLD, ranks second in the list of reasons for liver transplantation in the adult population. In the pathogenesis of this disease, metabolism and distribution of free fatty acids (FFA) play an important role. A large number of studies have established that the level of FFA in peripheral blood directly correlates with the severity of NASH, but it is still unclear what effect fluctuations in the profile of fatty acids (FA) in the liver have in steatohepatitis.Aim. Study of changes in the profile of fatty acids in the liver of laboratory animals with experimental non-alcoholic steatohepatitis.Materials and methods. The study was carried out on 17 white outbred male rats, which were randomized into two groups – intact (n = 6) and control (steatohepatitis) (n = 11). Steatohepatitis was modeled by 12-month use of a hypercaloric high-fat diet against the background of hypodynamia. The content of fatty acids in the liver was determined in the reaction of methanolysis and extraction with a hexane mixture of their methyl esters. The LC was separated by gas chromatography-mass spectrometry. Calibration for quantitative calculation was carried out with deuterated tridecanoic acid. The content of saturated and monounsaturated higher FAs, their aldehydes and hydroxy derivatives, as well as sterols were studied.Results and discussion. A total decrease in the content of FFA in the liver of animals with steatohepatitis was revealed. The most significant decrease occurred mainly in the class of monounsaturated fatty acids and cholesterol. Also, a significant decrease in the activity of Δ9-desaturase, a key enzyme in the synthesis of monounsaturated FAs from their precursor with the same carbon chain length, was revealed, which was manifested by a significant decrease in their amount in the liver. There were no statistically significant changes in the levels of aldehydes and hydroxy acids between the study groups, as well as in the level of sterols (except for cholesterol, the content of which decreased significantly).Conclusion. Thus, in the liver of rats with steatohepatitis caused by a combination of a hypercaloric diet and hypodynamia, statistically significant changes in the profile and concentration of fatty acids were found in comparison with healthy animals. The demonstrated shifts in FA composition may reflect both adaptive and pathological changes in the liver of animals with NAFLD and require further study.

2021 ◽  
Yang Liu ◽  
Kaihu Xian ◽  
Ruohua Gui ◽  
Kangkang Zhou ◽  
Junwei Liu ◽  

Crystals ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 1570
Maroua Ben Haj Salah ◽  
Justine Tessier ◽  
Nicolas Mercier ◽  
Magali Allain ◽  
Antonin Leblanc ◽  

Lead halide perovskites have emerged as promising materials for various optoelectronic applications. For photovoltaics, the reference compound is the 3D perovskite (MA)PbI3 (MA+ = methylammonium). However, this material suffers from instabilities towards humidity or light. This makes the search of new stable 3D lead halide materials very relevant. A strategy is the use of intermediate size cations instead of MA, which are not suitable to form the 3D ABX3 perovskites or 2D perovskites. Here, we report on a novel 3D metal halide hybrid material based on the intermediate size cation hydroxypropylammonium (HPA+), (HPA)6(MA)Pb5I17. We will see that extending the carbon chain length from two CH2 units (in the hydroxylethylammonium cation, HEA+) to three (HPA+) precludes the formation of a perovskite network as found in the lead and iodide deficient perovskite (HEA,MA)1+xPbxI3−x. In (HPA)6(MA)Pb5I17 the 3D lead halide network results from a 2D perovskite subnetworks linked by a PbI6 octahedra sharing its faces. DFT calculations confirm the direct band gap and reveal the peculiar band structure of this 3D network. On one hand the valence band has a 1D nature involving the p orbitals of the halide. On the other, the conduction band possesses a clear 2D character involving hybridization between the p orbitals of the metal and the halide.

Physchem ◽  
2021 ◽  
Vol 1 (3) ◽  
pp. 288-296
Richail Dubien Moulandou-Koumba ◽  
Frédéric Guégan ◽  
Jean-Maurille Ouamba ◽  
Samuel N’Sikabaka ◽  
Gilles Frapper

Betaine derivatives, especially esters, are compounds of interest for the development of a more sustainable fine chemistry, as they are widely available from biomass and currently produced as side-products from various industries (among which, sugar production). In this publication, we studied the impact of carbon chain length on three considered reaction mechanisms for the esterification of (CH3)3N(CH2)nCO2 betaine (n = 1, 2, 3) with glycerol under acid catalysis. DFT calculations show that the mechanism proposed by Bachmann–Frapper et al. may also be active here, but it can interestingly be seen as an avatar of the former proposition by Watson. Conversely, Ingold’s proposition is in this case too energetically prevented. Overall, lower activation barriers and higher reaction exergonicity are reported, suggesting esterification of longer carbon-chain based betaines is more readily achieved.

2021 ◽  
Vol 12 ◽  
Hongwei Wen ◽  
Ying Wang ◽  
Bangbang Wu ◽  
Yanru Feng ◽  
Yifei Dang ◽  

As a barrier for plants to contact with the outside world, epidermal wax plays an important role in resisting biotic and abiotic stresses. In this study, we analyzed the effect of wax content on leaf permeability by measuring the wax loss rate in the leaf. To further clarify the wax composition of the wheat epidermis and its molecular regulation mechanism, we applied untargeted lipidomic and transcriptome analysis on the leaf epidermis wax of Jimai 22 low-wax mutant (waxless) and multi-wax mutant (waxy). Our research showed that the mutant waxy has a slow loss rate, which can maintain higher leaf water content. 31 lipid subclasses and 1,367 lipid molecules were identified. By analyzing the wax differences of the two mutants, we found that the main lipid components of leaf epidermis wax in Jimai 22 were WE (C19-C50), DG (C27-C53), MG (C31-C35), and OAHFA (C31-C52). Carbon chain length analysis showed that, in wheat epidermis wax, WE was dominated by C44 molecules, DG was mainly concentrated in C47, C45, C37, and C31 molecules, C48 played a leading role in OAHFA, and C35 and C31 played a major role in MG. Among them, DG, MG, and OAHFA were detected in wheat leaf wax for the first time, and they were closely related to stress resistance. Compared with the waxy, 6,840 DEGs were detected in the mutant waxless, 3,181 DEGs were upregulated, and 3,659 DEGs were downregulated. The metabolic pattern of main waxy components in the wheat epidermis was constructed according to KEGG metabolic pathway and 46 related genes were screened, including KSC, TER, FAR, WSD1, CER1, MAH1, ALDH7A1, CYP704B1, ACOT1_2_4, CYP86, MGLL, GPAT, ALDH, DPP1, dgkA, plsC, and E2.3.1.158 related genes. The screened wax-related genes were confirmed to be highly reliable by qRT-PCR. In addition, we found TER gene TraesCS6B03G1132900LC in wheat mutant waxless leaves for the first time, which inhibited the synthesis of long-chain acyl-CoA (n+2) by downregulating its expression. These results provide valuable reference information for further study of wheat epidermis wax heredity and molecular regulation.

2021 ◽  
Catharina Vendl ◽  
Patrice Pottier ◽  
Matthew D. Taylor ◽  
Jennifer Braeunig ◽  
Matthew J. Gibson ◽  

Per- and polyfluoroalkyl substances (PFAS) are ubiquitous in the environment and often ingested with food. PFAS exposure in people can have detrimental health consequences. Therefore, reducing PFAS burdens in food items is of great importance to public health. Here, we investigated whether cooking reduces PFAS concentrations in animal-derived food products by synthesizing experimental studies. Further, we examined the moderating effects of the following five variables: cooking time, liquid / food item ratio, cooking temperature, carbon chain length of PFAS and the cooking category (oil-based, water-based & no-liquid cooking). In our systematic review searches (including the grey literature), we obtained 512 effect sizes from 10 relevant studies. These studies exclusively explored changes in PFAS concentrations in cooked seafood and freshwater fish. Our phylogenetically controlled multilevel-meta-analysis has revealed that, on average, cooking reduced PFAS concentrations by 28%, although heterogeneity among effect sizes was very high (I2 = 94.65%). Our five moderators cumulatively explained 36% of the observed heterogeneity. Specifically, an increase in cooking time and liquid / animal tissue ratio, as well as shorter carbon chain length of PFAS (when cooked with oil) were associated with significant reductions in PFAS concentrations. The effects of different ways of cooking depended on the other moderators, while the effect of cooking temperature itself was not significant. Overall, cooking can reduce PFAS concentrations in blue food (seafood and freshwater fish). However, it is important to note that complete PFAS elimination requires unrealistically long cooking times and large liquid / animal tissue ratios. Currently, literature on the impact of cooking of terrestrial animal produce on PFAS concentrations is lacking, which limits the inference and generalisation of our meta-analysis. However, our work represents the first step towards developing guidelines to reduce PFAS in food via cooking exclusively with common kitchen items and techniques.

2021 ◽  
Vol 903 ◽  
pp. 81-86
Kristaps Māliņš ◽  
Ilze Malina ◽  
Mara Legzdina

The catalytic hydrotreatment of sunflower (SO), linseed (LO), coconut (CO), rapeseed (RO), and its soapstock derived acid oil (RS) over commercial Ni65%/SiO2-Al2O3 catalyst was investigated to evaluate utilization feasibility of various vegetable oil feedstocks with different fatty acid content, composition, and saturation for marketable hydrocarbon production. The active metal loading of catalyst was characterized by XRF and its textural properties by N2 sorption analysis. The hydrotreatment tests of different vegetable oils were carried out in solvent free medium, under initial H2 pressure 10 MPa, at operating temperature 340 oC, and residence time 15 min using catalyst amount 5%. GC-FID and GC-MS analysis were used for estimation of dominant n-pentadecane, n-hexadecane, n-heptadecane, n-octadecane, and other hydrocarbon contents in obtained samples. Under studied hydrotreatment conditions complete conversion of different vegetable oils into marketable liquid renewable hydrocarbons without presence of oxygen containing substances was achieved. Highly active Ni65%/SiO2-Al2O3 has remarkable selectivity to hydrocarbons produced by reaction pathways, where elimination of carbonyl groups occurs. The saturation of fatty acids in feedstock determines H2 consumption, but influence on produced hydrocarbon production is insignificant. Depending on the fatty acid composition different saturated linear hydrocarbons with wide range of carbon chain length C5-C19 and similar calorific value 47.16-47.34 MJ/kg were produced in process. Overall liquid hydrocarbon yields were from 44.6 % to 78.1 %. The highest overall liquid saturated linear hydrocarbon yield was observed for feedstock with high amount of long chain fatty acids – SO, LO, RO and RS. Pure hydrocarbons obtained from vegetable oils depending on hydrocarbon composition can be used in various areas.

2021 ◽  
pp. 1-21
Yaoyuan Zhang ◽  
Wenbin Zhao ◽  
Haoqing Wu ◽  
Zhuoyao He ◽  
Yong Qian ◽  

Abstract A recent proposed dual-fuel combustion mode, intelligent charge compression ignition (ICCI), realizes the high-efficiency and clean combustion by organizing continuous stratification in a wide range of engine load. The paper investigated the performance of alcohol blended gasoline as low reactivity fuel (LRF) in ICCI combustion mode. Pure ethanol named E100 was also tested as LRF for comparison. To emphasize the differences of LRF properties and exclude the effect of the heat release phasing, the diesel injection timing was adjusted to maintain the same combustion phasing (CA50) at various LRF ratios under medium load. The results showed that E100 and E85 (ethanol ratio in gasoline-ethanol blend) promoted the degree of homogeneous combustion and eradicated soot emissions despite a slight increase of NOx. The maximum indicated thermal efficiency (ITE) was over 51.1% using E85, followed by 50.5% of E50. The perfect substitution ratio at the maximum ITE decreased from more than 80% to about 65% when increasing the ethanol ratio in LRF from 10% to 100%. The unregulated emissions such as aldehydes, ethylene, and methane, produced from incomplete combustion of ethanol were inhabited by E85, while the formation of toluene attributed to the appropriate carbon chain length of gasoline diminished when using E85 and E100.

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