152 research outputs found
Molecular Dynamics Simulation Of Gas Transport And Adsorption In Ultra-Tight Formations
Kerogen, which plays a very important part in reservoir characterization for ultra-tight formations, is also involved in the storage and production of hydrocarbons in shale. In this work, we study the kerogen structure and its interaction with insitu hydrocarbons to fully understand the fluid flow and adsorption mechanisms in the shale. Also the advancement in pore network modelling has greatly helped the understanding of mesoscale fluid flow. In this work, transport of methane in a type II marine environment kerogen model is studied using molecular dynamics simulations. Non Equilibrium Molecular Dynamics Simulations (NEMDS) using GROMACS code and Grand Canonical Monte Carlo (GCMC) using the RASPA code have been applied to simulate the adsorption and transport of ethane, carbon dioxide and methane in nanoscale environment. In this work, we used the kerogen and silica pore models to represent an organic and inorganic nanopore channels, respectively. The initial configuration models are then energy minimized, and both constant-temperature constant-volume (NVT) simulations and then constant-temperature constant-pressure (NPT) simulations are performed to obtain the final structure.
For our pore network model, we used the Delaunay triangulation method to build a network model and then employed capillary pressure simulations. The simulation results from molecular simulations transport diffusivities show that as pressure increases the transport diffusion coefficients increase. Methane has a higher diffusivity in kerogen than ethane at the same temperature and pressure conditions.
For adsorption, results show that CO2 has the largest adsorption capacity for both organic and inorganic pores, hence, a good candidate for enhanced gas recovery and carbon sequestration in depleted shale gas reservoirs. The amount of adsorption is more in organic pores for all studied gases, which implies that shale reservoirs with higher total organic carbon (TOC) will turn to trap more gases restricting flow and production
Convergent synthesis and light harvesting properties of dendritic boradiazaindacene (BODIPY) appended perylenediimide dyes
A convergent synthesis methodology, together with "click- chemistry" between azides and terminal alkynes, allows straighforward access to dendritic light harvesting systems. The novel dendrimer reported in this study has eight boradiazaindacene (BODIPY) units at the periphery and a perylenediimide (PDI) dye at the core. We have demonstrated that visible light is effectively collected as a result of the large absorption cross section of the dendrimer and efficiently channeled to the core PDI unit, resulting in a significant antenna effect. While being one of the very few energy transfer systems with a BODIPY and PDI chromophore pair, this novel dendritic molecule is one of the most efficient in light harvesting. The factors that may play important roles as the generation number increases also become apparent when emission characteristics were analyzed in comparison with a lower generation dendrimer. © 2010 The Royal Society of Chemistry and the Centre National de la Recherche Scientifique
Energy Flow in the Hadronic Final State of Diffractive and Non-Diffractive Deep-Inelastic Scattering at HERA
An investigation of the hadronic final state in diffractive and
non--diffractive deep--inelastic electron--proton scattering at HERA is
presented, where diffractive data are selected experimentally by demanding a
large gap in pseudo --rapidity around the proton remnant direction. The
transverse energy flow in the hadronic final state is evaluated using a set of
estimators which quantify topological properties. Using available Monte Carlo
QCD calculations, it is demonstrated that the final state in diffractive DIS
exhibits the features expected if the interaction is interpreted as the
scattering of an electron off a current quark with associated effects of
perturbative QCD. A model in which deep--inelastic diffraction is taken to be
the exchange of a pomeron with partonic structure is found to reproduce the
measurements well. Models for deep--inelastic scattering, in which a
sizeable diffractive contribution is present because of non--perturbative
effects in the production of the hadronic final state, reproduce the general
tendencies of the data but in all give a worse description.Comment: 22 pages, latex, 6 Figures appended as uuencoded fil
A Search for Selectrons and Squarks at HERA
Data from electron-proton collisions at a center-of-mass energy of 300 GeV
are used for a search for selectrons and squarks within the framework of the
minimal supersymmetric model. The decays of selectrons and squarks into the
lightest supersymmetric particle lead to final states with an electron and
hadrons accompanied by large missing energy and transverse momentum. No signal
is found and new bounds on the existence of these particles are derived. At 95%
confidence level the excluded region extends to 65 GeV for selectron and squark
masses, and to 40 GeV for the mass of the lightest supersymmetric particle.Comment: 13 pages, latex, 6 Figure
Оценка воздействия производственной деятельности теплогенерирующего предприятия на атмосферный воздух
Объектом исследования теоретической части работы является исследование котельных установок и газоочистных установок для очистки промышленных газов. Объектом исследования практической части работы является анализ воздействия выбросов загрязняющих веществ от объектов ООО «Бакчартепло».The object of study the theoretical part of the work is to study the boiler plants and gas-cleaning unit for cleaning industrial gases. The object of study of the practical work is to analyze the impact of emissions from the facilities of OOO "Bakcharteplo"
Jets and energy flow in photon-proton collisions at HERA
Properties of the hadronic final state in photoproduction events with large transverse energy are studied at the electron-proton collider HERA. Distributions of the transverse energy, jets and underlying event energy are compared to \overline{p}p data and QCD calculations. The comparisons show that the \gamma p events can be consistently described by QCD models including -- in addition to the primary hard scattering process -- interactions between the two beam remnants. The differential jet cross sections d\sigma/dE_T^{jet} and d\sigma/d\eta^{jet} are measured
Разработка интерактивной моделирующей системы технологии низкотемпературной сепарации газа
We present a study of J ψ meson production in collisions of 26.7 GeV electrons with 820 GeV protons, performed with the H1-detector at the HERA collider at DESY. The J ψ mesons are detected via their leptonic decays both to electrons and muons. Requiring exactly two particles in the detector, a cross section of σ(ep → J ψ X) = (8.8±2.0±2.2) nb is determined for 30 GeV ≤ W γp ≤ 180 GeV and Q 2 ≲ 4 GeV 2 . Using the flux of quasi-real photons with Q 2 ≲ 4 GeV 2 , a total production cross section of σ ( γp → J / ψX ) = (56±13±14) nb is derived at an average W γp =90 GeV. The distribution of the squared momentum transfer t from the proton to the J ψ can be fitted using an exponential exp(− b ∥ t ∥) below a ∥ t ∥ of 0.75 GeV 2 yielding a slope parameter of b = (4.7±1.9) GeV −2
CMS physics technical design report : Addendum on high density QCD with heavy ions
Peer reviewe
- …