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Online since: December 2012
Authors: Ya Ming Yao, Zi Qi Yang
The theory of non-structural reservoir formed in In twentieth Century 30-40.In the second half of the twentieth Century,with Rapid development ofOil and gas exploration theory and technology, petroleum geology theorys were relevant to all areas of petroleum geology. applicated plate structure theory in petroliferous basin analysis and integrated and penetrated Geology with geochemistry Since 1980, Integrated study on Oil and gas reservoir formation conditions and distribution have carried out All over the world.
Its characteristics is based on modern geological theory, apply mathematics, physics, chemistry and Biology, use advanced computer and test, simulation technology, and Quantitatively study on mechanism, rate and process of oil and gas generation, migration, accumulation and preservation.
Deep basin gas theory On 1979, Masters called gas reservoir in sandstone in the lower position or central syncline structure as deep basin gas.
People have been able to on the applicate the seismic data and drilling and logging data to predicte and identify basin structure, sedimentary facies types and regional distribution in basin simulation.the sign of comprehensive development is the comprehensive analysis of sea level change by P.R.Vail et al ( 1988) and literature published by Sangree, Wagoner and Mitchum et al.
Oil and gas geochemical method and technology As a branch of earth chemistry, Oil reservoir geochemistry is developed in the late 80's, is product of the traditional organic and inorganic geochemistry and geological reservoir.
Online since: April 2016
Authors: Jana Szewieczková, Vojtěch Enev, Irena Türkeová, Leos Doskocil, Martina Klučáková
Fluorescence analysis of Cu(II), Pb(II) and Hg(II) ion binding to humic and fulvic acids Vojtěch Enev 1,a *, Irena Türkeová 1,b, Jana Szewieczková 1,c, Leoš Doskočil 1,d and Martina Klučáková 1,e 1Institute of Physical and Applied Chemistry, Materials Research Centre, Faculty of Chemistry, Brno University of Technology, Purkyňova 118, Brno, 612 00, Czech Republic axcenev@fch.vutbr.cz, bxcturkeovai@fch.vutbr.cz, cxcszewieczkovaj@fch.vutbr.cz, ddoskocil@fch.vutbr.cz, eklucakova@fch.vutbr.cz Keywords: humic substances, titration, steady-state fluorescence spectroscopy, Stern-Volmer equation, fluorescence quenching Abstract.
The fact that ESFA exhibited lower EET/EBz ratio than ESHA indicates that the aromatic structures in ESFA probably have been substituted by a greater degree with aliphatic functional groups.
These results show that the aromatic structures in ESHA have higher degree of substitution with O-containing functional groups.
Higher value of E4/E6 ratio of ESFA maybe indicates the presence of structures with lower molecular weight and degree of humification.
Two adjacent aromatic carboxyl groups (i.e., a phthalic acid-like binding site) and an aromatic carboxyl group and adjacent phenolic OH group (i.e., a salicylic acid-like binding site), in the HA structure are known to form highly stable bidentate complexes with metal ions [8].
Online since: May 2013
Authors: Ning Ren Jin, Biao He, De Ming Zhao, Jian Ting Zhang, Xing Wei
The compression resistance and composite bonding of the polymer greatly increased because of the network structure formed by H-N…O-H…N intermolecular and O-H…N intramolecular hydrogen bond (Eq. 2).
The commercial PBI, which contains a typical structure of 2,2’-metaphenylene-5,5’-bisbenzimidazole, is produced by melt polycondensation of 3,3’,4,4’-tetra-aminobiphenyl (TAD) and diphenylisophthalate (DPIP) at 270-400℃ then solution spinning in DMAc or dry spinning[9].
For the hydroxy modified PBI, the PDBI fiber has the optimum heat resistance and is the optimal polymer structure.
Journal of Polymer Science: Part A: Polymer Chemistry, vol. 40(2002), p. 3703~3710
Journal of Polymer Science: Polymer Chemistry Edition, vol. 14(1976), p. 2807~2817.
Online since: May 2026
Authors: Muhammad Yaqub, Muhammad Talha
Water Absorption Test Absorption behavior exposes paradoxical additive dynamics where material chemistry and microstructure interact counter-intuitively.
All mixes exhibited near-identical 28-day mass depletion (~170g from initial), confirming acid penetration bypasses additive chemistry except 15% bentonite (Mix04) which showed accelerated early dissolution (3761g/3d) yet paradoxically minimal strength loss.
This structure, made of calcium silicate-clay composites, is highly resistant to acid, effectively turning a damaging process into a strengthening one.
· Reserve the high-dosage combination of both materials exclusively for structures in highly corrosive environments.
International Journal of Concrete Structures and Materials, 17(1), 25. https://link.springer.com/article/10.1186/s40069-023-00585-5
Online since: October 2014
Authors: Davide Tumino, Tommaso Ingrassia, Vincenzo Nigrelli
With this approach, however, the structure obtained is usually overdimensioned.
The dimension of the structure domain is 160x100x1 mm.
The structure obtained at the end of the optimization process is shown in figure 4.
Radiation curing of carbon fibre composites (2014) Radiation Physics and Chemistry, 94 (1), pp. 14-17.
[17] Rodriguez, J., Seireg, A.A., Optimizing the shapes of structures via a rule-based computer program, Comput.
Online since: May 2012
Authors: Hui Ying Xu, Jian Wei Zou, Wei Wang
Many previous studies showed that it was indeed feasible to predict the properties with quantitative structure-property relationship (QSPR) models for many organic compounds.
The advantage of this approach over other modeling methods is that only the knowledge of molecular structure is required.
Generally speaking, for the compounds with similar structure, the larger the molecular is, the stronger the intermolecular dispersion force.
Conclusion Quantitative structure and soot–water partition coefficients (logKSC) established for 25 investigated persistent organic pollutants has been established.
Acknowledgements This work was financially supported by State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences (KF2011-19).
Online since: July 2010
Authors: Yong Yang, Xin Zhe Lan, Yong Hui Song, Ting Su, Huan Zhan
The results showed that the absorption and deposition of the Ag nuclei initially occurred at the active sites on the core surfaces as seeds which urged the further deposition of silver species to form sprinkled-structure core-shell particles.
Bimetallic powders with core-shell structure, such as silver-coated copper [3, 4], are effective ways to solve the oxidation problems, and changing the copper particles into lead-free conductive and thick film is also a considerable method [5].
However, well-dispersed and eugenic core-shell structures are still under exploring.
In this paper, the well-dispersed copper particles and core-shell structure are prepared through the simple reduction of CuSO4 and AgNO3 aqueous solution without ammonia by hydrazine hydrate in the presence of PVP.
It's more interesting that both particles have lots of small spots on the films or layers, thus exhibit a sprinkled-structure with a size of 1μm.
Online since: December 2012
Authors: Ku Zilati Ku Shaari, Suriati Sufian, Mohd Fikri Mokhtar, Erny Haslina Abd Latib
Surface area and pore structure 3.2.1.
There are mixtures of meso and micropores in the structure.
This is because the structure collapsed when it reaches high temperature activation.
Thus, it is very interesting to study the structure of the surface after activation.
Activated carbon from jackfruit peel waste by H3PO4 chemical activation: Pore structure and surface chemistry characterization.
Online since: December 2007
Authors: Tomasz Rzychoń, Andrzej Kiełbus, Bożena Bierska-Piech
This phase has an f.c.c. structure (a = 2.2 nm), which makes it isomorphous with Mg5Gd.
The β" metastable phase has a D019 hexagonal structure and is coherent with the α-Mg (a = 2aMg, c = cMg) matrix.
The β' transient phase has a base centered orthorhombic structure and is semicoherent with the α-Mg phase (a = 2aMg, b ≈ 8dMg(1-100), c = cMg).
The structure was refined to Rwp = 7.08 % and S = 1.93 %.
This equilibrium phase has face centered cubic crystal structure with the lattice parameter of a = 2.24 nm, which makes it isomorphous with the Mg5Gd compound.
Online since: February 2014
Authors: Hong Cheng Pan, Lin Chen, Yuan Ming Zhang
Co-electrodeposition and characterization of Ag-Ag2S-PbS thin films on indium–tin-oxide coated glass Yuanming Zhanga, Lin Chenb, and Hongcheng Panc College of Chemistry and Bioengineering, Guilin University of Technology, Guilin 541004, P.
The X-ray diffraction analysis demonstrated the presence of cubic structure of metallic silver, acanthite Ag2S, and cubic PbS, which is consistent with the CV analysis.
XRD analysis shows three distinct diffraction peaks of 38.08°, 44.28°, and 64.38° at 2θ values indexed to (111), (200), and (220) the crystalline planes of the face-centered cubic structure of metallic silver.
These 2θ values could be well indexed to PbS with cubic crystal structure (JCPDS 05-0592).
The X-ray diffraction analysis revealed the presence of cubic structure of metallic silver, acanthite Ag2S, and cubic PbS.