fragment composition
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2021 ◽  
Author(s):  
D. T. Olua

The geology of the Metaweja area is characterized by the turbidite sequence which are deposited in the deep-sea environment during the Miocene and exposed to surface due to the latest deformation. The research was conducted to identify the potential source rock and reservoir rock within the turbidite deposits. In the study area, there are three types of rock units, calcareous shale units formed in the Late Miocene, Sandstone unit and interbedded siltstone-sandstone unit that were deposited in Middle Miocene. Measured section was carried out at the several stations in order to analyze the turbid current deposition mechanism. Measured section of the alternating unit of sandstone - siltstone are observed at several places where the unit has intercalation of shale, coal and iron oxide. Some syn-depositional sedimentary structure also found within this unit. The carbonate shale unit has good total organic content (TOC) ranging from 0.51wt% to 2.56wt%. Pyrolysis analysis has S2 value 1.31 mg/g to 1.34 mg/g, Hydrogen Index (HI) 35 mgHC/g to 49 mgHC/g, Oxygen Index (OI) 35 mgHC/g to 49 mgHC/g, Tmax 430 °C to 434 °C and Vitrinite Reflecteance index (Ro) 0.32% to 0.54%. The carbonate shale characterized as the type III kerogen which prone gas source rock and interpreted as immature to early mature source rock. The petrography analysis of alternating rocks of sandstone - siltstone has characteristics of sandstones with 44% of volcanic lithic fragment composition, 20% matrix 10% clay size fragments, secondary porosity reaches 10% and 13% cement carbonate calcite. Based on the petrography analysis, this unit could be interpreted as reservoir rock, although we need further analysis for the Permeability measurement.


Molecules ◽  
2021 ◽  
Vol 26 (16) ◽  
pp. 5039
Author(s):  
Luca Pinzi ◽  
Annachiara Tinivella ◽  
Giulio Rastelli

Tau is a highly soluble protein mainly localized at a cytoplasmic level in the neuronal cells, which plays a crucial role in the regulation of microtubule dynamic stability. Recent studies have demonstrated that several factors, such as hyperphosphorylation or alterations of Tau metabolism, may contribute to the pathological accumulation of protein aggregates, which can result in neuronal death and the onset of a number of neurological disorders called Tauopathies. At present, there are no available therapeutic remedies able to reduce Tau aggregation, nor are there any structural clues or guidelines for the rational identification of compounds preventing the accumulation of protein aggregates. To help identify the structural properties required for anti-Tau aggregation activity, we performed extensive chemoinformatics analyses on a dataset of Tau ligands reported in ChEMBL. The performed analyses allowed us to identify a set of molecular properties that are in common between known active ligands. Moreover, extensive analyses of the fragment composition of reported ligands led to the identification of chemical moieties and fragment combinations prevalent in the more active compounds. Interestingly, many of these fragments were arranged in recurring frameworks, some of which were clearly present in compounds currently under clinical investigation. This work represents the first in-depth chemoinformatics study of the molecular properties, constituting fragments and similarity profiles, of known Tau aggregation inhibitors. The datasets of compounds employed for the analyses, the identified molecular fragments and their combinations are made publicly available as supplementary material.


2020 ◽  
Vol 22 (4) ◽  
pp. 315
Author(s):  
R.Kh. Salakhov ◽  
M. Seitzhanova ◽  
D.U. Bodykov ◽  
L.R. Sassykova ◽  
N.K. Zhakirova ◽  
...  

In order to change the viscosity of high-resinous oil of the “Karazhanbas” field (Kazakhstan), the effect of electrohydraulic action on it was studied. The effect of adding an organic solvent xylene on the rheological properties of oil is investigated. A comparative study of the hydrocarbon composition of oil before and after electrohydraulic impact was carried out by the method of gas chromatographymass spectrometry. Fragment composition of oil hydrocarbons before and after electrohydraulic treatment was determined by 1H and 13C NMR spectroscopy. It is shown that the conversion of heavy oil fractions to light ones begins with a five-time electrohydraulic impact. It is determined that 20‒25 electric discharge pulses are sufficient for the quantitative process of splitting hydrocarbons. It was found that the addition of xylene to high-viscosity oil leads to an increase in the conversion of hydrocarbons under electrohydraulic action. The content of paraffins and naphthalenes in high-viscosity oil is slightly reduced during electrohydraulic processing. In oil, after electrohydraulic action, a decrease in the proportion of protons of long alkyl terminal СН3-groups of hydrocarbons is observed, which indicates the process of decomposition of heavy oil fractions into light fractions.


2020 ◽  
Vol 16 (4) ◽  
Author(s):  
Xiu-Yuan Qin ◽  
Jiang-Tao Zhang ◽  
Guo-Ming Li ◽  
Mu-Yi Cai ◽  
Jun Lu ◽  
...  

AbstractA selenium-chelating corn oligopeptide (Se-COP) with high protein and low molecular weight was prepared as a selenium supplement. We utilized infrared (IR), ultraviolet (UV), and circular dichroism (CD) spectroscopy, 1-anilinonaphthalene-8-sulfonate (ANS)-binding fluorescence spectra, and isothermal titration calorimetry (ITC) to analyze and describe Se-COP and its reactions. It was concluded that the chelation reaction was a spontaneous process driven by enthalpy and entropy, with ΔH=3.79 × 104 ± 4075 cal/mol, ΔS = 146 cal/mol, ΔG = –23356.30 ± 126.94 cal/mol, binding constant Ka = 1.18 × 104 ± 855 M–1, and binding site number n = 0.13 ± 0.0126, and described as coordination bonds forming and hydrophobic interaction, as well as protein conformational changes including secondary and tertiary hydrophobic structure. Se-COP had strong antioxidant capacity, and mass spectrometry (MS) was used to identify the antioxidant peptide fragment, which was characterized as LLPPY and quantified at 428.95 ng/mg. This study indicated that Se-COP prepared by chelation may be a Se supplement with antioxidant capacity that can be applied in functional foods or ingredients.


KURVATEK ◽  
2018 ◽  
Vol 2 (2) ◽  
pp. 55-66
Author(s):  
Siti Nuraini

Nanggulan  Conglomeratic  Sandstone  is  one  of  important  part  of     Nanggulan  Formation  which  is deposited during   Middle Eocene to early Late Eocene (Saputra & Akmaluddin, 2015) or Late Oligocene (Rahardjo, 1995). The grain composition of Nanggulan conglomeratic sandstone  is characterized by various rock fragments (metamorphic, igneous, sedimentary rocks) which mixture up to fine to coarse sand-sized matrix. Other materials present within the Nanggulan conglomerathic sandstone are shell fragments, coal remains, siderithic concretions which is deposited within high energy condition. Geometry of conglomeratic sandstone  stratification is still being  a question  among the researchers  due to discontinuous  sand body character.   To study external form of sandstone body needs to combine with internal characters such are grain texture, grain or fragment composition, sedimentary structures to predict a depositional facies. This research is dedicated to study the character of the Nanggulan conglomeratic sand body. Field geological observation was conduct to two rivers i.e Kali Watupuru and Kali Songgo where transecting the Nanggulan beds.  The  grain  or  fragments  concentration  of  Nanggulan  conglomeratic  sandstone  displays  in  various condition for example lying above an erosional surface to the bottom position, or concentrate to the upper layer. It also appears to be engaged in coarser size matrix, or displays a dense grain composition to elsewhere. Geometry of the Nanggulan conglomeratic sandstone represents a lens geometry  which pinching-out to the edge of body.   However, to the top of lens geometry were found steep joints cross cutting the sand layers. Initial geometry of Nanggulan conglomeratic sandstone indicates a channel fill shape due to filling sediments into the erosional feature of underlying beds. When lithification and compaction process occurred along the burial and uplifting tectonic phase, a channel fill geometry becomes lens geometry. Bulging to the centre part and thinning to the edge of sandstone body, is caused by differential compaction process. Lens geometry is believed as one example of structural trap model for sandstone reservoir. The occurrences of vertical joints to the Nanggulan conglomeratic sandstone need to be considered as seal potential within clossure trap or even more causing hydrocarbon leakings.  If development of vertical joint occurs along migration process, it may be potentially leak. However, if joints already sealed parts of hydrocarbon pool may create a compartmentalization  reservoir  body.  By  doing  this  investigation  could  predict  an  advance  reservoir modelling study using outcropp analogues.   Keyword: Nanggulan conglomeratic sandstone, lens geometry, sandstone body.


2014 ◽  
Vol 87 (8) ◽  
pp. 1070-1076 ◽  
Author(s):  
E. V. Maltseva ◽  
A. V. Savel’eva ◽  
A. A. Ivanov ◽  
N. V. Yudina ◽  
O. I. Lomovskii

2012 ◽  
Vol 68 (1) ◽  
pp. 86-94 ◽  
Author(s):  
V. D. Tikhova ◽  
T. F. Bogdanova ◽  
V. P. Fadeeva ◽  
V. N. Piottukh-Peletsky

2012 ◽  
Vol 5 (1) ◽  
pp. 67-82 ◽  
Author(s):  
Diana-Carolina Cruz-Forero ◽  
Oscar-Andrés González-Ruiz ◽  
Luis-Javier López-Giraldo

This paper validates and implements an Extended Constituent Fragments methodology (ECF) for the calculation of thermophysical properties of vegetable oils considering the latter as triglyceride (TAG's) mixtures, both homogeneous and heterogeneous. For this purpose, three different vegetables oils were chosen (soybean oil, canola and olive) and their TAG's profiles were estimated using the ECN 42 generalized method. The ECF methodology estimates the properties of TAG's from their fragment composition and specific parameters of each property, which are adjusted using experimental information available in literature. The average relative errors of calculated properties were between 1 and 32% depending on the oil and the property. These errors were significantly lower than those obtained using the Aspen HYSYS commercial software, which oscillates between 70 and 100%. Additionally, by extrapolating the constituent fragments methodology a method for calculating boiling temperatures of TAG's with average relative errors of ~1% was proposed. The calculations of properties for the ECF method were performed using the OIL-CALPROP software developed specifically for this purpose.


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