Diagram Parameters Research Articles

Early oil charging from Sinian shales in Ordovician carbonates of the Tabei Uplift, Tarim Basin: Evidence from biomarkers

Despite over 40 years of exploration focusing on the deep to ultra-deep Ordovician carbonates as major hydrocarbon targets in the Tarim Basin, the identification of their source rocks remains elusive. Based on biomarkers, carbon and sulfur isotopes of hydrocarbons, the primary source for the Ordovician petroleum system has been attributed mainly to the lower Cambrian shales, although some oils were likely contributed from the Lower Ordovician source rocks. However, the current understanding of the evolution of the Ordovician petroleum system remains rudimentary, largely due to the complex interplay of multi-source (i.e., the widespread Precambrian shales) hydrocarbon inputs, diagenetic alterations, and tectonic processes over geological time. This study systematically investigates the molecular geochemistry of reservoir bitumen within the Ordovician carbonates from Tabei uplift, coupled with bitumen from the Sinian units at the western edge of the Tarim Basin. Our results indicate that the ion chromatography-mass spectrometry spectra and the saturated to aromatic hydrocarbons ratio of Ordovician reservoir bitumen closely resemble those of Sinian bitumen, as well as the published data of Sinian shales. This coupling linkage is revealed by cross-plots and ternary phase diagrams of various biomarker parameters, which can effectively distinguish the Sinian sources from other sources, i.e., the Lower Cambrian and Ordovician, for the Ordovician reservoir bitumen. Specifically, the ∑n-C21-/∑n-C22+, Pr/Ph, G/C31H22S, C23/C21TT ratios are effective indexes to differentiate these source rocks. By compiling the published organic geochemistry data of oils, it appears to infer that approximately 8.1% of the present-day oils produced from the Ordovician carbonates likely contain some proportion of Sinian-sourced oils. The recognition of Sinian sourced oils contributing to the paleo- and present-day Ordovician petroleum system offers valuable insights for the exploration of deep-ultra deep carbonates in the Tarim Basin, emphasizing the need to consider Precambrian shales as a significant hydrocarbon source.

Assessment of groundwater quality and its vulnerability for safe drinking purpose

ABSTRACT Groundwater is a main resource of drinking water in several parts of India. Its degradation poses a significant risk to water availability and human health, highlighting the importance of regularly evaluating groundwater quality in these regions. Thus, the significant aim of this study is to examine and map groundwater quality and its vulnerability for drinking purposes using the EWQI, PIG, and GOD methods. The quality of groundwater in the study area is found to be generally alkaline in nature. More than 20% of samples exceeded the desirable limit of TH. Correlations of major ions revealed that groundwater samples were distributed in the areas of silicate weathering and dolomite dissolution. The EWQI values vary from 33.74 to 62.22, with an average value of 41.54. The spatial distribution diagrams of hydrochemical parameters and EWQI represent poor water quality in southern and southern-western areas. The PIG ranged from 0.49 to 0.84, with an average value of 0.59. Moreover, the GOD method indicates that the southern part of the region has moderate vulnerability and demonstrates that groundwater level is the significant factor for the calculation of groundwater vulnerability.

ON-BOARD CONTROL-MEASUREMENT SYSTEM FOR MICRO CONVERTIPLANE-TYPE UNMANNED AERIAL VEHICLES

The article describes the on-board control-measurement system designed to record the main flight parameters of a micro-convertiplane type unmanned aerial vehicle and the element base used for this purpose. The methodology of conducting tests in stationary mode through the on-board control-measurement system was developed and tests were carried out. The engine's diagnostic check and condition assessment has been performed using the on-board control-measuring system. The possibility of on-ground check of the micro unmanned aerial vehicles power elements before and after the flight, as well as the possibility of monitoring the flight events that may occur in the air during the flight has been shown. The data on the power consumption and temperature of each engine in the stationary mode, the direction of the aircraft axes and the velocity vector have been recorded by mean of the developed on-board control-measurement system, as well as time dependence diagrams of the corresponding parameters have been built in comparative order based on the obtained values. A methodology has been developed for the diagnostics of the engine operation of the micro-unmanned aerial vehicle before and during the flight. It has been shown that the temperature, power consumption and number of revolutions of the engines included in the power system of the aircraft, as well as the aircraft axes and velocity vector direction data is recorded during the flight, by mean of the on-board control-measurement system designed to collect data on the flight-technical parameters of the convertiplane-type micro-unmanned aerial vehicles.

Fractal properties of the Nd<sub>100–x</sub>Fe<sub>x</sub> alloys surface in the fractal thermodynamics model

The study of the fractal properties of the surface of Nd100–xFex alloys in a wide range of concentrations х (х = 20–90) was carried out in the framework of the fractal thermodynamics model. To this end, we performed an analysis of images obtained by (scanning electron?) microscopy of the surfaces of a series of Nd100–xFex alloys synthesized by induction melting. A high degree of proximity of the surface structure of all the studied samples, both before and after etching, to fractals is shown. The values of the parameter δ characterizing the relative deviation of the studied samples from the fractal are in the range of 0.017–0.029. Three-dimensional diagrams of the fractal parameters Sf , Tf , Ef , x and two-dimensional diagrams of the same parameters: Sf , Tf , Ef , x, reflecting the nature of the state of the surfaces of Nd100–xFex alloy samples before and after etching, are constructed. For all investigated samples of alloys, the values of the parameters of the fractal equations of state arecalculated. The correlation of the maximum value of the coercive force Hc = 4.8 kE with the values of fractal entropy Sf = 39.86, fractal temperature Tf = 529, and fractal dimension D = 2.6530 of the Nd100–xFex alloys at x = 20 has been established.

Structural and optical properties of Zn2.95Ga2−xSnO8:xCr3+: An excellent X-ray charging-based persistent phosphor

This study investigates structural and luminescence properties of Cr3+ doped Zn2.95Ga2SnO8 phosphor. XRD analysis determines the phase purity and lattice parameters, while SEM and TEM analysis were utilized to study the particle size and surface morphology of the sample. UV–visible absorption and PL excitation spectra provided information on the excitation bands and the band-gap of both the undoped and Cr3+ doped Zn2.95Ga2SnO8. The optical band-gap of the material decreases upon doping with Cr3+ ions. Analysis of the Racah parameter and Tanabe Sugano diagram highlights a robust crystal field within Cr3+: Zn2.95Ga2SnO8, causing 2Eg level to become the lowest excited state with sharp emission at 699 nm. Concentration quenching at higher Cr3+ concentrations (> 0.6 mol%) is primarily attributed to the quadrupole-quadrupole interactions. Two distinct traps with trap depths at 0.51 eV and 0.73 eV were identified by using thermoluminescence measurement. The material gives persistent luminescence with a decay time of more than 30 min when charged with blue light (420 nm) and an excellent decay time of more than 16 h when charged with X-rays. Notably, this is the first report on X-ray charging-based persistent luminescence in Zn2.95Ga2SnO8. The outstanding persistent luminescence makes this material highly promising for various applications.

Using a Parameter Diagram as a DoE Planning Tool

This paper describes the p-diagram (parameter-diagram) and its application in planning a DoE (Design of Experiments). A case study describing an actual problem from industry is presented where the planning phase started to go wrong as difficulties in selecting the right variables for the DoE were discovered. Furthermore, running these experiments became prohibitively expensive, due to the large number of such experiments that would be needed, and though the exploitation of a p-diagram it was then possible to come up with a feasible DoE.

Symmetry and Asymmetry of Chaotic Motion in a Crank Arm and Connecting Rod Due to the Movement of the Follower

The symmetry and asymmetry of chaotic motion in the planar mechanism is investigated for a crank arm and connecting rod due to the motion of a flat-faced follower. The level of chaos is investigated using the conception of the Lyapunov exponent parameter and phase-plane diagram at different cam speeds with and without the use of coefficients of restitution. Moreover, the fast Fourier transform (FFT) of power spectrum analysis technique is used based on SNR factor values at different cam speeds and different coefficients of restitution. The wave forms and histograms of nonlinear responses are analyzed using the SolidWorks program for the crank arm, connecting rod, and flat-faced follower. There is a clearance between the flat-faced follower and its guides while the oscillation motion of the crank arm and connecting rod is described as the motion of a double pendulum. The level of chaos is increased with increases in the cam speeds and coefficients of restitution.

Heat-Driven Synchronization in Coupled Liquid Crystal Elastomer Spring Self-Oscillators.

Self-oscillating coupled machines are capable of absorbing energy from the external environment to maintain their own motion and have the advantages of autonomy and portability, which also contribute to the exploration of the field of synchronization and clustering. Based on a thermally responsive liquid crystal elastomer (LCE) spring self-oscillator in a linear temperature field, this paper constructs a coupling and synchronization model of two self-oscillators connected by springs. Based on the existing dynamic LCE model, this paper theoretically reveals the self-oscillation mechanism and synchronization mechanism of two self-oscillators. The results show that adjusting the initial conditions and system parameters causes the coupled system to exhibit two synchronization modes: in-phase mode and anti-phase mode. The work conducted by the driving force compensates for the damping dissipation of the system, thus maintaining self-oscillation. The phase diagrams of different system parameters are drawn to illuminate the self-oscillation and synchronization mechanism. For weak interaction, changing the initial conditions may obtain the modes of in-phase and anti-phase. Under conditions of strong interactions, the system consistently exhibits an in-phase mode. Furthermore, an investigation is conducted on the influence of system parameters, such as the LCE elastic coefficient and spring elastic coefficient, on the amplitudes and frequencies of the two synchronization modes. This study aims to enhance the understanding of self-oscillator synchronization and its potential applications in areas such as energy harvesting, power generation, detection, soft robotics, medical devices and micro/nanodevices.

Sensitivity of a collisional single-atom spin probe

We study the sensitivity of a collisional single-atom probe for ultracold gases. Inelastic spin-exchange collisions map information about the gas temperature T or external magnetic field B onto the quantum spin-population of single-atom probes, and previous work showed enhanced sensitivity for short-time nonequilibrium spin dynamics [Phys. Rev. X 10, 011018 (2020)]. Here, we numerically investigate the steady-state sensitivity of such single-atom probes to various observables. We find that the probe shows distinct sensitivity maxima in the (B,T) parameter diagram, although the underlying spin-exchange rates scale monotonically with temperature and magnetic field. In parameter space, the probe generally has the largest sensitivity when sensing the energy ratio between thermal energy and Zeeman energy in an externally applied magnetic field, while the sensitivity to the absolute energy, i.e., the sum of kinetic and Zeeman energy, is low. We identify the parameters yielding sensitivity maxima for a given absolute energy, which we can relate to a direct comparison of the thermal Maxwell-Boltzmann distribution with the Zeeman-energy splitting. We compare our equilibrium results to nonequilibrium experimental results from a single-atom quantum probe, showing that the sensitivity maxima in parameter space qualitatively prevail also in the nonequilibrium dynamics, while a quantitative difference remains. Our work thereby offers a microscopic explanation for the properties and performance of this single-atom quantum probe, connecting thermodynamic properties to microscopic interaction mechanisms. Our results pave the way for optimization of quantum-probe applications in (B,T) parameter space beyond the previously shown boost by nonequilibrium dynamics.

Elastic core concept for modified Bree problems considering in-phase and out-of-phase loading conditions

The elastic core concept developed from the Bree problem can be used for structural integrity evaluation of high temperature components, such as creep ratcheting and creep fatigue. The simplified inelastic analysis method of the ASME 2013 III-1 NH Code adopts the idea of core stress, which protects against creep rupture and collapse of the structure by limiting the accumulated inelastic strain. Currently, the formulas of core stress and evaluation diagram of effective creep stress parameter for Tests B-1 and B-3 adopted by the APPENDIX NH-T are developed from the classical loading Bree problem, however, the related concepts and evaluation diagrams of modified Bree problems considering generalized loading conditions have not been reported. This paper first reviews the development history of the elastic core concept and its corresponding analysis methods. Based on the modified Bree problems considering in-phase and out-of-phase loading developed by Bradford, the corresponding formulas of the core stress in the non-plastic ratcheting zone are completely proposed, and the corresponding evaluation diagrams of effective creep stress parameters are constructed for the first time. By comparing the core stress formulas and effective creep stress parameter diagrams under three loading cases, the conservatism and applicability of the classical core stress method are discussed. In addition, the differences and relations between two creep ratcheting assessment methods applicable to transient and sustained thermal load conditions respectively are clarified. The new results and conclusions presented in this paper can deepen the understanding of structural response under complex loading conditions, and provide guidance for shakedown analysis and creep ratcheting assessment of high-temperature components.

A novel chaotic map with a shifting parameter and stair-like bifurcation diagram: dynamical analysis and multistability

In this paper, the behavior of a 1D chaotic map is proposed which includes two sine terms and shows unique dynamics. By varying the bifurcation parameter, the map has a shift, and the system’s dynamics are generated around the cross points of the map and the identity line. The irrational frequency of the sine term makes the system have stable fixed points in some parameter intervals by increasing the bifurcation parameter. So, the bifurcation diagram of the system shows that the trend of the system’s dynamics changes in a stair shape with slope one by changing the bifurcation parameter. Due to the achieving multiple steady states in some intervals of the parameter, the proposed system is known as multistable. The multistability dynamics of the map are investigated with the help of cobweb diagrams which reveal an interesting asymmetry in repeating parts of the bifurcation diagram.

Critical conditions of forced ignition in Ni-Al, Ti-Al powder systems under solid-phase synthesis

A theoretical study of the critical conditions of forced solid-phase ignition in Ti-Al, Ni-Al systems was carried out. Based on the analysis of the non-stationary diffusion equation with moving boundaries, the critical powers of the heating source and the corresponding critical temperatures were determined during the formation of NiAl, TiAl3 intermetallic compounds using the state diagrams of these binary systems. The diffusion activation energies, frequency factors, particle sizes, and heat removal conditions were considered as variable parameters. The diagrams of critical parameters which relate the corresponding specific heating powers with the indicated values were constructed. It has been established that for the same values of the parameters and under identical synthesis conditions, the critical temperatures in these systems differ by more than one hundred degrees. The latter is associated with a significant difference in the width of the solubility region for the corresponding compounds of the composition NiAl, TiAl3. The performed analysis allows separating the modes of isothermal sintering and thermal explosion which makes it possible to control the thermal and diffusion modes of synthesis. The comparison of the calculation results with the experimental data showed their satisfactory agreement.

Simulation and optimization of thermal performance in diverging/converging manifold microchannel heat sink

Increasing complexity of electronic devices and chips places increasingly stringent requirements on heat sinks. A novel manifold microchannel heat sink with diverging/converging channels is proposed to improve heat transfer performance. The flow and heat transfer characteristics under single-phase are investigated numerically. The effects of two key parameters, manifold inlet to outlet ratio α and channel inlet to outlet ratio β, and their combinations on the thermal-hydraulic performance are explored. The results show that, in the single parameter optimization, a moderately diverging manifold layout and a converging channel layout each have the best enhancement effect on heat transfer for given pumping power, reducing the thermal resistance by 11.1% and 13.5% than homogeneous structure, respectively. When both parameters are set as optimization variables, the parameter combinations with enhanced performance are distributed in a sloping downward band in the parameter diagram. The configuration with α = 1/9 and β = 9 has the best reinforcement effect, reducing the thermal resistance by 19.18% for a given pumping power of 5×10−4 W. In addition, the heat transfer characteristics of the optimum and original configurations under non-uniform heating flux are also investigated for application, with the optimum configuration showing better performance at both temperature level and temperature uniformity.

Dynamics Reflect Gapless Edge Modes for Topological Superconductor

AbstractThe dynamical feature for a p‐wave superconductor model in different parameter regions in terms of the appearance of topologically gapless edge modes in reel geometry is investigated. First, the parameter region with gapless edge modes versus a parameter and quasi‐momentum is shown. The parameter diagram can be reflected by the expectations of Pauli matrices in global manners. In another view, the dynamical feature of the excitation behave differently in the parameter regions with topological gapless edge modes and not. And the cusps of dynamical return rate vanish as the parameter pass the topological phase boundary slowly enough. It is found that the dynamics in the parameter region with gapless edge modes behaves differently to that without edge modes and related mostly to the eigenenergy gap between the pre‐and post‐quench eigenstates. The cusps of the dynamical return rate behave robustly against the noise occurs during evolution in the lattice until localization behavior dominates. This work benefits detecting topological edge modes by dynamical manners.

A Combined Chaotic System for Speech Encryption

This paper presents a speech encryption scheme by performing a combination of modified chaotic maps inspired by classic logistic and cubic maps. The main idea was to enhance the performance of classical chaotic maps by extending the range of the chaotic parameter. The resulted combining map was applied to a speech encryption scheme by using the confusion and diffusion architecture. The evaluation results showed a good performance regarding the chaotic behaviors such as initial value, control parameter, Lyapunov exponent, and bifurcation diagram. Simulations and computer evaluations with security analysis showed that the proposed chaotic system exhibits excellent performance in speech encryption against various attacks. The results obtained demonstrated the efficiency of the proposed scheme compared to an existing valuable method for static and differential cryptographic attacks.

Textural characteristics, mode of transportation and depositional environment of the Stormberg Group in the Eastern Cape, South Africa: evidence from grain size and lithofacies analyses

Abstract The Stormberg Group comprises the Molteno, Elliot and Clarens formations and is one of four stratigraphical groups that make up the Karoo Supergroup in South Africa. The group is the highest unit in the Karoo Basin, representing the final phase of preserved sedimentation. The major problem with the Stromberg Group is that the mode of transport, hydrodynamic energy conditions and depositional environment are still poorly understood. For the present paper, grain size and lithofacies studies on selected sandstones from the Molteno, Elliot and Clarens formations were performed so as to elucidate their textural characteristics, depositional processes, sedimentation mechanisms and hydrodynamic energy conditions and to discriminate different depositional environments. The statistical parameters of grain size distribution (mean grain size, standard deviation, skewness and kurtosis) show that the sandstones are predominantly unimodal, fine grained, moderately well sorted, mesokurtic and near symmetrical. The bivariate diagrams of the aforementioned statistical parameters demonstrate that river and aeolian dune had the greatest impact on the depositional environments. Likewise, the C-M pattern (Passega diagram) shows that the sandstones were mostly deposited through tractive current process. Furthermore, the C-M diagram reveals the prevalence of rolling, suspension and graded suspension modes of sediment transportation. Seventeen sedimentary lithofacies were identified and grouped into seven lithofacies associations. These lithofacies associations indicate braided channel, overbank and swamp deposits for the Molteno Formation, alluvial fan/floodplain and playa deposits for the Elliot Formation and aeolian deposits for the Clarens Formation.

Softening mechanism and process parameters optimization of Ti-4.2Al-0.005B titanium alloy during hot deformation

The isothermal constant strain rate compression test of Ti-4.2Al-0.005B titanium alloy was carried out by Gleeble-3800 thermal simulator at temperature 850∼1050 °C, strain rate 0.001∼10s−1 and maximum deformation degree 60%. According to the experimental data, the Arrhenius constitutive model was established, the flow stress curve was analyzed, and the processing map based on polarity reciprocity model was established, which was further optimized by Zener-Hollomon parameter processing map and activation energy map. The results show that the flow stress curves respectively show dynamic recovery characteristics and dynamic softening characteristics under different deformation conditions respectively. The softening behavior of the flow stress curves under high strain rate is caused by temperature effect, while the softening behavior at low strain rate is caused by dynamic recrystallization. According to the established Polar Reciprocity Model processing map, the stable region is (870–990 °C/0.01–0.12s−1). Then, the Zener-Hollomon parameter processing map and activation energy processing map were established. Finally, the optimal processing parameters of the alloy are (870–990 °C/0.04–0.12s−1). The main deformation mechanism is dynamic recrystallization. Meanwhile, the rationality of Zener-Hollomon parameter diagram and activation energy diagram is verified. In the actual production process, the choice of technological parameters is provided in order to obtain good microstructure and properties.

Canard-induced mixed mode oscillations as a mechanism for the Bonhoeffer-van der Pol circuit under parametric perturbation

PurposeThis paper aims to investigate the singular Hopf bifurcation and mixed mode oscillations (MMOs) in the perturbed Bonhoeffer-van der Pol (BVP) circuit. There is a singular periodic orbit constructed by the switching between the stable focus and large amplitude relaxation cycles. Using a generalized fast/slow analysis, the authors show the generation mechanism of two distinct kinds of MMOs.Design/methodology/approachThe parametric modulation can be used to generate complicated dynamics. The BVP circuit is constructed as an example for second-order differential equation with periodic perturbation. Then the authors draw the bifurcation parameter diagram in terms of a containing two attractive regions, i.e. the stable relaxation cycle and the stable focus. The transition mechanism and characteristic features are investigated intensively by one-fast/two-slow analysis combined with bifurcation theory.FindingsPeriodic perturbation can suppress nonlinear circuit dynamic to a singular periodic orbit. The combination of these small oscillations with the large amplitude oscillations that occur due to canard cycles yields such MMOs. The results connect the theory of the singular Hopf bifurcation enabling easier calculations of where the oscillations occur.Originality/valueBy treating the perturbation as the second slow variable, the authors obtain that the MMOs are due to the canards in a supercritical case or in a subcritical case. This study can reveal the transition mechanism for multi-time scale characteristics in perturbed circuit. The information gained from such results can be extended to periodically perturbed circuits.

Computational analysis to evaluate one-dimensional rectilinear steady filtration flow of incompressible fluid through homogeneous reservoirs as exemplified by the Yarega field

The paper is concerned with a computational analysis of one-dimensional rectilinear steady filtration flows of incompressible fluids through homogeneous strata as exemplified by the Yarega field. It provides dependence diagrams of key parameters required to characterize the field. Based on the resultant data, it highlights the importance of further studies to evaluate filtration incompressible flows with an aim of enhancing productive oil recovery.

Effect of Hypromellose Acetate Succinate Substituents on Miscibility Behavior of Spray-dried Amorphous Solid Dispersions: Flory–Huggins Parameter Prediction and Validation

• Theoretical predictions and validation of miscibility was investigated. • Gibbs-composition phase diagram predicts the composition dependent miscibility. • Substituent ratios have significant effect on miscibility and drug loading. • Higher succinoyl content leads to higher dissolution efficiency. • Non-polar drugs show higher miscibility with HG grade, but low dissolution. This study reports the impact of physicochemical properties of lipophilic drugs such as Fenofibrate (FBT), Itraconazole (ITZ), Efavirenz (EFV) and Hydroxypropyl Methylcellulose Acetate Succinate (HPMCAS) grades on the miscibility, dissolution, and stability of the spray dried Amorphous Solid Dispersions (ASDs). The miscibility between of the drugs and HPMCAS grades was predicted using solubility parameter-derived Flory-Huggins interaction parameter and later phase diagram was constructed to delineate the composition dependent miscibility. By varying the HPMCAS grade−drug combinations and loadings, the amorphicity of prepared ASDs was analyzed using Differential Scanning Calorimetry (DSC), X-Ray Diffraction (XRD) and in vitro dissolution experiments were conducted to measure apparent solubility and finally, investigate the interplay between substituent ratio and functionality. Interactions between the drugs and polymeric grades and drug concentration in polymer is crucial in determining the drug precipitation within the ASDs which is further supported by Fourier Transform Infrared Spectroscopy (FTIR). The dissolution efficiency and dissolution rate of the ASDs were dependent on the acetyl-succinoyl ratio in HPMCAS.