Oxygen Compounds Research Articles

A Predictive Approach towards Using PC-SAFT for Modeling the Properties of Shale Oil.

Equations of state are powerful tools for modeling thermophysical properties; however, so far, these have not been developed for shale oil due to a lack of experimental data. Recently, new experimental data were published on the properties of Kukersite shale oil, and here we present a method for modeling the properties of the gasoline fraction of shale oil using the PC-SAFT equation of state. First, using measured property data, correlations were developed to estimate the composition of narrow-boiling-range Kukersite shale gasoline samples based on the boiling point and density. These correlations, along with several PC-SAFT equations of the states of various classes of compounds, were used to predict the PC-SAFT parameters of aromatic compounds present in unconventional oil-containing oxygen compounds with average boiling points up to 180 °C. Developed PC-SAFT equations of state were applied to calculate the temperature-dependent properties (vapor pressure and density) of shale gasoline. The root mean square percentage error of the residuals was 13.2%. The average absolute relative deviation percentages for all vapor pressure and density data were 16.9 and 1.6%, respectively. The utility of this model was shown by predicting the vapor pressure of various portions of the shale gasoline. The validity of this model could be assessed for oil fractions from different deposits. However, the procedure used here to model shale oil gasoline could also be used as an example to derive and develop similar models for oil samples with different origins.

UJI COD DAN MIKROBIOLOGI PADA SUMBER MATA AIR NIFUESU DESA BAUMATA UTARA KECAMATAN TAEBENU KABUPATEN KUPANG

Water is a very special chemical compound, which in its content consists of hydrogen compounds (H) and oxygen compounds (O). By Government Regulations No. 82 of 2001 concerning water management, water must meet the criteria of three parameters, namely physical parameters, chemical parameters, and microbiological parameters (Total Coliform). This study aims to determine the water quality in the Nifuesu spring, North Baumata village, Taebenu district, and Kupang regency based on chemical parameters (COD) and Microbiological parameters. The method used is a quantitative descriptive method with an experimental design by comparing the measurement data from each water parameter with the PP quality standard No.82 of 2001. These data show that the COD value at the point I is 7,86 mg/L and point II is 6.13 mg/L. About water quality standards according to PP No.82 of 2001, it can be concluded that the water quality parameters at the location of the Nifuesu spring for COD testing meet the drinking water quality standards set by the Government by the criteria for class I water quality standards 82 of 2001 which is 10 mg/L while the Total Coliformtest at the point I and point II obtained the same results, namely<2400/1000 mL which criteria meet the class II water quality standards set by the Government.Kata Kunci:COD, Mikrobiologi, Sumber Mata Air, NIfuesu

Effects of long-term (10 years) remediation of Caragana on soil enzyme activities, heavy metals, microbial diversity and metabolic spectrum of coal gangue

Phytoremediation is a means of remediation of coal gangue pollution. However, the molecular mechanism of the effect of long-term plant restoration on soil microecology has not been elucidated. This study explored the mechanism of soil-microbe-metabolite interaction after long-term recovery of Caragana korshinskii Kom. We analyzed the physical and chemical properties, enzyme activities, microbial community structure, metabolome and ionomics of the shallow (10 cm), middle (50 cm) and deep (100 cm) rhizosphere and bulk soils after C. korshinskii restoration for 10 years. The activities of soil urease, sucrase, and acid phosphatase mainly increased in the rhizosphere area of C. korshinskii. The microbial abundance increased by 8.5%, 25.0%, and 15.2% in the shallow, middle, and deep levels, respectively. The ionomics results showed that the total Sr, Mn, Fe, Th, Rb, Bi, S, Se, Pb, U, Ni, Ba content in the rhizosphere soil decreased by 0.10–1.06 times (Log2 FC), and the effective state elements increased by 0.21–2.24 times (Log2 FC), there is still a risk of metal pollution in the gangue area. Metabolomics shows that lipids and lipid molecules, organic acids, phenylpropane and polyketides are the main differential metabolites; C. korshinskii repair stimulates the circulation pathways of terpenoids, lipids, amino acids, and carbohydrates. S, Fe, Mn and lipids, organic acids, and organic oxygen compound metabolites drive Acidthiobacillus, Sulfurifustis, Deferrobacterium, Pseudomonas and Sphingomonas to become dominant strains, regulates element metabolism and accelerates the process of environmental restoration.

Metabonomic Characteristics of Myocardial Diastolic Dysfunction in Type 2 Diabetic Cardiomyopathy Patients.

Diabetic cardiomyopathy (DCM) is one of the most essential cardiovascular complications in diabetic patients associated with glucose and lipid metabolism disorder, fibrosis, oxidative stress, and inflammation in cardiomyocytes. Despite increasing research on the molecular pathogenesis of DCM, it is still unclear whether metabolic pathways and alterations are probably involved in the development of DCM. This study aims to characterize the metabolites of DCM and to identify the relationship between metabolites and their biological processes or biological states through untargeted metabolic profiling. UPLC-MS/MS was applied to profile plasma metabolites from 78 patients with diabetes (39 diabetes with DCM and 39 diabetes without DCM as controls). A total of 2,806 biochemical were detected. Compared to those of DM patients, 78 differential metabolites in the positive-ion mode were identified in DCM patients, including 33 up-regulated and 45 down-regulated metabolites; however, there were only six differential metabolites identified in the negative mode including four up-regulated and two down-regulated metabolites. Alterations of several serum metabolites, including lipids and lipid-like molecules, organic acids and derivatives, organic oxygen compounds, benzenoids, phenylpropanoids and polyketides, and organoheterocyclic compounds, were associated with the development of DCM. KEGG enrichment analysis showed that there were three signaling pathways (metabolic pathways, porphyrin, chlorophyll metabolism, and lysine degradation) that were changed in both negative- and positive-ion modes. Our results demonstrated that differential metabolites and lipids have specific effects on DCM. These results expanded our understanding of the metabolic characteristics of DCM and may provide a clue in the future investigation of reducing the incidence of DCM. Furthermore, the metabolites identified here may provide clues for clinical management and the development of effective drugs.

Physical properties and sensory acceptability of gum arabic-coated cherry tomato fruit during storage

Cherry tomato is a small climacteric fruit with a short shelf life ranging from 5 to 7 days due to postharvest diseases, accelerated ripening, and senescence, all of which cause losses in quantity and quality. An edible coating can be used to extend the shelf life of fresh fruits by acting as a barrier against the transfer of oxygen, carbon dioxide, moisture, aroma, and volatile compounds during storage. This research focused on the effect of gum arabic on the physical properties and sensory acceptability of cherry tomatoes during cold storage at 13 and 25˚C. Weight loss, firmness, and colour (L*, C*, and h*) of control and coated cherry tomato fruits were measured during storage at 13 and 25˚C, as well as the sensory acceptability of samples after 16 days at 13˚C. Coating cherry tomatoes with gum arabic (2-5% w/w) significantly decreased weight loss while maintaining firmness and colour during storage. In sensory evaluation, the coated samples obtained the same or significantly higher acceptability scores than the control samples, especially in appearance, texture, and overall acceptance

Processing of oxidized nickel ores using sintering, roasting and leaching processes

• The initial ore consists of α-iron oxide (74%) in a magnetically ordered phase. • After firing at 700 °C, iron oxide α-Fe2O3 (91%) prevails. • Optimum roasting temperature is 650 °C. • Crystalline hematite forms at temperatures above 700 °C. • Extraction of nickel into solution is 78.5%, cobalt −92.2%. The article is devoted to the results of research into the process of sintering, roasting and leaching of oxidized nickel ores, with selection of optimal parameters that include the addition of various reagents, varying the temperature, duration and roasting program, as well as creating the necessary atmosphere in the roasting furnace. It was revealed that only a small part of ferruginous minerals forms iron sulfate during sulfation with sulfuric acid, even at elevated temperatures. It is possible to reduce the loss of nickel binded with oxygen compounds of iron after the roasting at temperatures not exceeding 650 °C, while recrystallization of iron oxides occurs with the formation of α-Fe 2 O 3 , and the nickel is released, that can be leached. In general, the sintering and roasting process makes it possible to achieve a higher extraction of nickel and cobalt; it is shown that nickel, being a part of various ore minerals, is available for extraction at different stages of ore processing.

Signals of low grade organic matter alteration in the Upper Permian Kupferschiefer (Spremberg area, Eastern Germany) – A by-product of copper mineralization?

Organic matter (OM) is known to be an important reductant in many sediment-hosted base metal deposits. However, the precise nature of the interactions between OM and hydrothermal fluids is still debated, as is just how such interconnected reactions develop over geological timescales. We investigated the Kupferschiefer mineralization in two drill cores from the Spremberg-Graustein field in Eastern Germany focusing on the inventory of organonitrogen, -sulfur and -oxygen (NSO) compounds, which are most affected by organic–inorganic interactions with mineral surfaces, metals and aqueous fluids. Rather homogeneous deposition of type II marine organic matter, prevailing photic zone euxinia and an early oil window thermal maturity were documented using conventional hydrocarbon analysis. Furthermore, a slight level of hydrothermal alteration was detected in the lower part of drill core 121 h/72, in proximity to the epigenetic hematitic alteration zone known as ‘Rote Fäule’. A minor loss of extractable organic matter and especially long-chain n-alkanes was accompanied by significant enrichment in oxygenated compounds and increased molecular oxygen content detected by ultra-high resolution mass spectrometry (FT–ICR–MS). A strong enrichment of deuterium observed in the n-alkanes (up to −36‰) and isoprenoids (up to −20‰) indicates that hydrogen exchange with an evaporitic fluid occurred in the Spremberg Kupferschiefer over geological timescales at maximum temperatures not exceeding 110 °C. We therefore conclude that FT–ICR–MS, combined with determination of stable hydrogen isotope compositions, can provide valuable information about interaction time scales and the origin of mineralizing hydrothermal fluids.

Position dispersive X-ray fluorescence

A novel scanning-free wavelength dispersive X-ray fluorescence spectrometer has been developed by combining low power X-ray tubes with X-ray optics. The X-rays are focused to a single point on the sample and then dispersed onto a flat diffracting crystal where they are spread depending on their energy through Bragg's law of diffraction onto a silicon strip detector. Throughout this study, the proposed method is referred to as Position Dispersive X-ray Fluorescence (PDXRF). The X-ray emission spectra of vanadium and copper as well as, CuO, CuS2 and V2O5 were measured. In the spectrometer energy resolutions of 3.14 eV and 8.94 eV FWHM were measured for V and Cu when measuring over a range of 4.8–5.8 keV and 6.2–9.1 keV respectively. The Kβ line shapes were fitted with a series of Voigt profiles and the energies and intensities of the Kβ valence transition peak, Kβ2,5, were determined. There was also sufficient variation in the intensity ratio of Kβ2,5/Kβ1,3 that the oxygen and sulphur compounds of V and Cu could be successfully observed and measured. The result demonstrates that this experimental setup is capable of measuring the Kβ line shape at resolutions of a few eV, allowing for chemical state analysis to be performed on 3d transition metals and their compounds such as the measurement of redox reactions to aid in battery development.

Differential metabolome responses to deltamethrin between resistant and susceptible Anopheles sinensis

Insecticide-based vector control measures play an important role in the prevention and control of insect-borne infectious diseases such as malaria; however, insecticide resistance has become a severe global problem for vector control. To date, the metabolic mechanism by which Anopheles sinensis, the most widely distributed malaria vector in China and Asia, detoxifies insecticides is not clear. In this study, the molecular metabolite changes in both the larval and adult stages of deltamethrin susceptible (DS) and deltamethrin-resistant (DR) An. sinensis mosquitoes were analysed by using liquid chromatography tandem mass spectrometry (LC-MS/MS) after exposure to deltamethrin. There were 127 differential metabolites in larval DR An. sinensis and 168 in adults. Five metabolites (glycerophosphocholine, deoxyguanosine, DL-methionine sulfoxide, D-myo-inositol-3-phosphate and N-acetyl-alpha-D-glucosamine1-phosphate) were downregulated in both DR larvae and adults, and one metabolite (aspartyl-glutamine) was upregulated, and the ratio of down- and up-regulation of these metabolites was 5:1. The differential metabolites between the DS and DR mosquitos were mainly classified into organic oxygen compounds, carboxylic acids and their derivatives, glycerophospholipids and purine nucleotides, and the common pathway enriched in both the larval and adult DR An. sinensis was glycerophospholipid metabolism. The findings of this study provide further mechanistic understanding of insecticide resistance in An. sinensis.

Electrochemical Hydroxylation of Electron‐Rich Arenes in Continuous Flow

AbstractElectrochemical hydroxylation of arenes by trifluoroacetic acid provides a straightforward access to aryl oxygen compounds under the mild and environmental benign reaction conditions. Harmful and pollutant stoichiometric amounts of oxidation reagents and the use of metal‐catalysts can be avoided. Herein, we present a novel method for the synthesis of hydroxylated products from electron‐rich arenes that was achieved by the implementation of a continuous‐flow setup. The continuous nature of the process allowed to fine‐tune the reactions conditions in order to prevent the decomposition of the sensitive products expanding the reaction scope beyond electron‐poor and neutral arenes that were previously reported in the batch processes. Thus, synthetically valuable hydroxylated arenes were obtained in good yields with the residence time just over a minute. In order to demonstrate the reliability and the efficiency of the electrochemical flow setup, a scale up experiment was also performed.

Solar energy‐based extraction of essential oils from cloves, cinnamon, orange, lemon, eucalyptus, and cardamom: A clean energy technology for green extraction

AbstractConventional essential oil extraction systems cannot meet the green extraction concepts and sustainable development goals (SDGs). Therefore, there is a need to develop alternative systems based on clean energy. The present study aims to investigate the possibility of essential oil extraction using solar energy without utilizing synthetic solvents. Hence, an eco‐friendly solar energy‐based extraction system (SEE) was developed to extract essential oils from cloves and cinnamon barks, orange and lemon peels, eucalyptus leaves, and cardamom seeds. Essential oils were assessed in terms of yield, physical properties, and chemical composition using gas chromatography–mass spectrometry assay. Also, the process sustainability was analyzed by the green extraction evaluation approach, and results were compared with those of traditional hydro‐distillation (THD). Replacing THD with SEE increased the extraction time by 0.65, 0.80, 0.41, 0.61, 0.39, and 0.45 h for processing clove, cinnamon, orange, lemon, eucalyptus, and cardamom, respectively. The optimum solar radiation for extraction was about 1000 W/m2. Also, oxygen compounds (96.45, 79.640, 42.98, and 83.76%) comprised the main proportion in the clove, cinnamon, eucalyptus, and cardamom essential oils, while orange and lemon essential oils had a high presence of terpenes. Furthermore, essential oils obtained by SEE had a similar yield and alcohol solubility to THD. According to green extraction process analysis, solar energy‐based extraction was 23–34% greener than THD, depending on the type of plant material.Practical ApplicationsThe innovative solar‐based extraction system designed and developed in this research can be used at farms and small factories to obtain essential oils using the zero‐energy concept. From the energy consumption viewpoint, this technology can be regarded as “free process” which can reduce production costs. Also, the unique design of the heating section of this new system prevents overheating of the sample, making this new solar‐based system suitable for the extraction of thermolabile compounds from plant materials. In this sense, obtaining a high‐quality essential oil without running cost (in terms of electricity cost), relatively small size, and low capital cost makes this system practical for future applications.

Urinary metabolomics identified metabolic disturbance associated with polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is a common endocrine and metabolic disorder. Nevertheless, its accurate mechanisms remain unclear. Metabolomics is a powerful technique to identify small molecules that could be used to discover pathogenesis and therapeutical targets of disease. In the present study, a urinary untargeted metabolomics combined with targeted quantification analysis was performed to uncover metabolic disturbance associated with PCOS. A total of thirty-eight metabolites were obtained between PCOS patients and healthy controls, which were mainly involved in lipids (39.5%), organic acids and derivatives (23.7%), and organic oxygen compounds (18.4%). Based on enrichment analysis, fourteen metabolic pathways were found to be perturbed in PCOS, particularly glycerophospholipid metabolism and tryptophan metabolism. Targeted quantification profiling of tryptophan metabolism demonstrated that seven compounds (tryptophan, kynurenine, kynurenic acid, quinolinic acid, xanthurenic acid, 3-hydroxyanthranilic acid and 3-hydroxykynurenine) were up-regulated in PCOS. And these tryptophan-kynurenine metabolites showed significant correlations with PCOS clinical features, such as positively associated with testosterone, free androgen index, and the ratio of luteinizing hormone to follicle stimulating hormone. Thus, this study disclosed urinary metabolome changes associated with PCOS, and might provide new insights into PCOS pathogenesis elucidation and therapeutical target development.

Nitrogen–Sulfur–Oxygen compounds in the study of oil migration in Block TW, eastern flank of the Oriente Basin, Ecuador

Nitrogen–Sulfur–Oxygen compounds of crude-oil samples were analyzed to study oil migration in Block TW. The 15 crude-oil samples of the Upper Cretaceous Napo Formation M1ss Member had similar geochemical characteristics; a similar normal alkane distribution mode (forward peak-single peak model); and similar terpane, hopane, and regular sterane distribution characteristics, which are similar to those of the Upper Cretaceous marl in the eastern flank. The nitrogen compounds of the crude oils from the M1ss Member in Block TW show a prominent geochromatographic effect-an obvious decrease in the total absolute abundance of pyrrole (a kind of biomarker), absolute abundance of exposed pyrrolic hydrogen. The ratios of “shielded pyrrolic hydrogen/exposed pyrrolic hydrogen” and “partially shielded pyrrolic hydrogen/exposed pyrrolic hydrogen” increase with oil migration while the ratios of “shielded pyrrolic hydrogen/partially shielded pyrrolic hydrogen” exhibited almost no change. The ratios of 1,8-/2,6-dimethylcarbazole, 1,4-/2,6-dimethylcarbazole, and 1,5-/2,6- dimethylcarbazole were good indicators of oil migration, which greatly decreased in short-distance migration in the Johanna reservoir and Alice West reservoir and could be used to semiquantitatively analyze the oil migration direction within the same reservoir. The main oil migration in Block TW was from southwest to northeast, and the geochromatographic effects between different reservoirs were not obvious, which might be the results of different oil charging points, different migration pathways, or the simultaneous supply of local and far sources. Heteroatomic compounds of oxyfluorene and thiofluorene series have strong biodegradation resistance and can assist in identifying the direction of oil migration. The variation trend of total abundance of oxyfluorene and thiofluorene in Block TW is similar to that of carbazole series compounds, but the migration fractionation effect is not as obvious as that of pyrrole series compounds. A set of parameters should be used in studying oil migration, which can be determined according to most of their variation trends. The ratios of 1,8-/2,6-dimethylcarbazole, 1,4-/2,6-dimethylcarbazole, and 1,5-/2,6-dimethylcarbazole in the M1ss Reservoir of Block TW have similar and obvious geochromatographic effects, which can be used as regional oil and gas migration indicators. The pyrrole compounds (particularly the carbazole series) have obvious geochromatographic effects along with oil migration, which could be used to analyze its direction, particularly in highly explored areas with several wells.

Urinary metabolomics reveals the biological characteristics of early pregnancy in pigs

BackgroundEmbryo implantation in sows is an important event during pregnancy. During this process, blastocysts undergo dramatic morphologic changes, and the endometrium becomes receptive. Studies have shown that developmental changes associated with the crosstalk between peri-implantation embryos and embryo-uterine are driven by various biomolecules secreted by the endometrium and embryos. In sows, changes in the uterus are also reflected in circulating body fluids and urine. Metabolomics reveals the metabolic state of cells, tissues, and organisms. In this study, we collected urine samples from large white sows during the peri-implantation period. The levels of urinary metabolites at different periods were analyzed using ultra-performance liquid chromatography/tandem mass spectrometry (UPLC–MS/MS) analysis techniques.ResultsA total of 32 samples were collected from 8 sows during the estrus period and at each phase of early pregnancy (9, 12, and 15 days of gestation). A total of 530 metabolites were identified with high confidence in all samples. Compared with samples collected during the estrus phase, 269 differential metabolites were found in samples obtained during early pregnancy.ConclusionsThe identified metabolites included lipids and lipid-like molecules, organic acids and their derivatives, organic oxygen compounds, organoheterocyclic compounds, benzenoids, among others. Metabolites, such as choline and pregnanediol-3-glucuronide, play important roles in pregnancy in sows and other animals. These results reveal the metabolic changes in urine of sows during early pregnancy phase. The differential urinary metabolites can be used for assessing peri-implantation status in sows. Understanding these metabolic changes may promote the management of pregnant sows through various interventions such as provision of proper nutrition.

Metabonomics Analysis of Stem Extracts from Dalbergia sissoo.

Dalbergia sissoo is a woody plant with economic and medicinal value. As the pharmacological qualities and properties of the wood from this plant primarily depend on its extractives, in this study, the metabolomic analysis of extractives from its stems was carried out using UPLC-MS/MS. A total of 735 metabolites were detected from two groups of samples, heartwood and sapwood, with the largest number of terpenoids in type and the largest number of flavonoids in quantity. The PCA and cluster analysis showed significant differences in the metabolite composition between the two groups. The differential metabolites were mainly organic oxygen compounds, flavonoids, and isoflavones. Among the 105 differential metabolites, 26 metabolites were significantly higher in relative content in sapwood than in heartwood, while the other 79 metabolites were significantly higher in relative content in heartwood than in sapwood. KEGG metabolic pathway enrichment analysis showed that these differential metabolites were mainly enriched in three metabolic pathways: Flavonoid biosynthesis, isoflavonoid biosynthesis, and flavonoid and flavonol biosynthesis. This study provides a reference for metabolomics studies in Dalbergia and other woody plants.

Пространственно-временна́я изменчивость гидрохимических показателей водной среды Обской и Тазовской губ

The Gulf of Ob and Taz Bay are components of a special geographical object — Ob-Tar estuarine area. They are intensively used by companies, which produce natural gas and oil in the Yamal Region. The aim of the study is to assess the spatial patterns and temporal dynamics of the priority hydrochemical characteristics of the Gulf of Ob and Taz Bay. The data of the Arctic estuarine expeditions (1968—1989) and complex expeditions (2012—2013), organized by the Arctic and Antarctic Research Institute, are used as the research materials The authors have analyzed hydrochemical characteristics: pH, salinity, dissolved oxygen, silicon and phosphorus compounds. In summer-autumn period 2012—2013 there was a significant seawater intrusion to the south of the Gulf of Ob, caused by a small runoff of rivers the in these dry years. Dissolved oxygen distribution is determined by seasonal variability. In summer-autumn period the average values of more than 7 mg/l were observed. In winter, in the southern part of Gulf of Ob and Taz Bay there was an extreme oxygen deficit, dissolved oxygen values dropped below 1 mg/l. A tendency for a decrease in the content of silicon and phosphorus compounds from south to north was noted. Concentrations of phosphorus-containing compounds in the whole water area were low. The condition of Taz Bay and southern part of the Gulf of Ob is mainly determined by the river runoff and the hydrochemical regime in the area. In the period of high waters the regime has features inherent to rivers, and in the period of low flows — to lakes and reservoirs. Large-scale interference in the ecosystem of Ob-Taz estuarine area recently requires regular hydrological-ecological observations at coastal stations and along the water area sections.

Insight into Geochemical Significance of NO Compounds in Lacustrine Shale Source Rocks by FT-ICR MS

Nitrogen and oxygen (NO) compounds are important compositions in shale source rocks, and they carry an abundance of geochemical information for hydrocarbon generation. Due to technical limitations, the significance of NO compounds has not been paid enough attention. In this paper, the NO compounds from shale rocks of the Dongpu Depression are analyzed to explore the compositional characteristics and geochemical significance of using geological and organic geochemical ways of rock-eval, gas chromatography-mass spectrometry (GC/MS), and Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS). The results show that shale rocks are rich in NO compounds, with twelve types of compounds that were detected: N1, N1O1, N1O2, N1O3, N1S1, N1S2, N2O1, O1, O2, O3, O3S1, and O4. Of these compounds, O2 and O3 predominated, followed by N1 and N1O1. Of the N1 species, the most abundant classes are DBE of 9, 12, 15, and 18, which changed with maturity. Of the O2 species, compounds of DBE of 1 (fatty acids) are the predominant class. Classes of DBE 5 and 6 in the O2 species are naphthenic acids with special biological skeleton structures, which are usually appear in immature and low-mature oils. N1, O2, and N1O1 compounds are affected by their maturity and they often run to polarization with enhanced DBE species and a shorter carbon chain as their maturity increases. The parameters of DBE18–25/DBE9–18-N1 and DBE12–20/DBE5–12-O2 increase with the increase of buried depth and maturity. The NO compounds that were revealed by FT-ICR MS may have a promising application in distinguishing between the different depositional environments. Source rocks of saline lacustrine are rich in O2 and N1O1, but less N1 and O1 compounds. The research results are of vital importance for expanding the application of the NO molecular compounds in petroleum exploration.

Community Structure of Seagrass in Harapan Island, Seribu Islands, Indonesia

Seagrass is an aquatic biota that is ecologically and economically beneficial. This study aims to determine the community structure of seagrass in Harapan Island, Seribu Islands, Indonesia. The research was conducted using purposive sampling method, that divided into two sites which is considered to represent the ecology’s condition of Harapan Island. The site 1 was located adjacent to the mangroves area, while the site 2 was placed near a reclamation development and ship anchoring. Every site had three subsites as replications, each was 50 meters apart. Water parameters temperature, salinity, turbidity, pH, dissolved oxygen (DO), depth, and organic compound of each site were measured. The results showed that coverage of seagrass in site 2 is higher than site 1 that categorized as frequent-common coverage. The site 2 had the density of 220 individuals seagrass per square meter that dominated by Cymodocea rotundata. The highest diversity index was found in the site 1 at 1.15, with the lowest dominance index being 0.39. The distribution pattern in site 1 is clustered and uniform, while site 2 is uniform. The Importance Value Index in site 1 was 114,8 by Halodule uninervis, while site 2 was 125,5 by C. rotundata. It is thought that the low diversity of seagrass at the site 2 due to it was near a reclamation development and ship anchoring that disturb the abundance and community structure of seagrass in Harapan Island. Habitat destruction and anthropogenic impact of seagrass need to be minimized to support environmental coastal and fisheries sustainability.

Calculation of Start-Up Time of Passive Catalytic Hydrogen Recombiner of Localization Safety System of a Nuclear Power Plant Equipped with VVER

The hydrogen removal system ensures hydrogen safety. At a VVER nuclear power plant, it consists of passive catalytic hydrogen recombiners. The calculation of devices is of great importance for safety justification, since the complex conditions of an accident at a power unit are not reproducible in experiments. The recombiner consists of a casing and a cassette with catalytic elements, the design of which ensures the passage of a gaseous medium through the device. Upon contact with the catalyst, a chemical reaction of hydrogen and oxygen compounds occurs, accompanied by the release of heat; as a result, the concentration of hydrogen under the shell decreases. The problem is starting from a cold state since the activity of the cold catalyst is low, and the thrust is not observed until the catalyst is heated and a column of warm gas is formed inside the device. The transition from the cold state to the working state takes a certain time, during which the recombiner performance is below nominal. The start-up time is a parameter that is important in terms of safety. The article calculates the start-up time of a hydrogen recombiner with a catalytic block in the form of equidistant parallel catalytic plates. Local cross-sectional averages and transmission coefficients are used, the latter taking into account the influence of free convection and chemical reaction. The gas velocity is determined by the balance of buoyant and resistance forces. The calculated data and the data known from the scientific and technical literature coincide satisfactorily. As a conservative estimate of the start-up time of the recombiner, it is recommended to use the value of 300 s. An increase in temperature practically does not affect the start of the recombiner with an active catalyst, an increase in the concentration of hydrogen accelerates the start, and a decrease in pressure slows it down. The results obtained in the study can be used in the justification of the safety of VVER nuclear power plants and the examination of reports on the justification of the safety of power units.

Non-targeted metabonomic analysis of plasma in patients with atherosclerosis by liquid chromatography-mass spectrometry.

BackgroundThis study sought to analyze non-targeted plasma metabolites in patients with atherosclerosis (AS).MethodsThe plasma of patients with AS (the patient group) and the plasma of age-matched and gender-matched healthy individuals (the control group) at the Taihe Hospital was collected. One hundred patients were included in the study (60 in the patient group and 40 in the control group). Fasting venous plasma was collected in the morning. The metabolites in the plasma were examined by liquid chromatography-mass spectrometry (LC-MS). An unsupervised principal component analysis (PCA) was conducted to observe the overall distribution of each sample and the stability of the analysis process. Next, a supervised partial least squares-discriminant analysis (PLS-DA) and an orthogonal partial least squares-discriminant analysis (OPLS-DA) were conducted to examine the overall differences among the metabolic profiles of the groups and identify different metabolites in the groups. Pathway enrichment was analyzed using the Kyoto Encyclopedia of Genes and Genomes (KEGG) database.ResultsIn total, 1,126 different metabolites were detected in the patient and control groups. Compared to the control group, 411 species decreased, and 715 species increased in the patient group. There were 61 different metabolites with a variable weight in the projection (VIP) >1 and a P<0.05. There were 34 types of lipid metabolites, 10 types of carbon and oxygen compounds, 8 types of organic acids and derivatives, 4 types of organoheterocyclic compounds, 3 types of nitrogen-containing organic compounds, and 2 types of nucleotides and analogs. Compared to the control group, 47 species decreased, and 14 species increased in the patient group. The following 9 metabolites had the most significant differences (|log2fold change| >1; P<0.05): 2-tetradecanone, pantothenol, all-trans-13,14-dihydroretinol, linoleoyl ethanolamide, N-oleoylethanolamine, 4-methyl-2-pentenal, Cer (d18:1/14:0), chenodeoxycholic acid glycine conjugate, and 5-acetamidovalerate. The enrichment analysis results of the 61 different metabolite pathways identified 17 metabolic pathways with significant differences (P<0.05), including the choline metabolism, lipid metabolism, autophagy, amino acid metabolism, vitamin digestion, and absorption pathways.ConclusionsThere are significant differences in non-targeted plasma metabolites between patients with AS and healthy individuals. The above-mentioned 9 most significantly different metabolites may be potential markers of AS.