bluuebunny/crossref_metadata_2025 huggingface dataset:
Evolution of the electrical characteristics of an atmospheric pressure dielectric barrier discharge system over one hour operation
Authors: Destrieux A , Profili J , Laurent M , Naudé N , Laroche G
Published: October 2023

In this work, long-time operation of a dielectric barrier discharge (DBD) characterized by a single thin dielectric was investigated. The discharge was operated under nitrogen at atmospheric pressure in a typical filamentary regime. Electrical measurements were performed, i.e. applied voltage, current and charge were retrieved. The Lissajous figure method combined with an equivalent circuit of the DBD was used to calculate the dissipated power, estimate the gas gap voltage

V

g

, evaluate the deposited charges

Q
0

as well as the capacitances of the discharge cell. The results over a one-hour operation indicated that the total dissipated power remained constant, but a decrease of the gas gap voltage with an increase of the charge deposited was also depicted. For the capacitances, both dielectric and cell capacitances variations were studied from the Lissajous figures. The dielectric capacitance showed a voltage dependency over half a period of applied voltage.
Potential of electrolyte-gated transistors for anionic molecule detection: proof of concept using dye solution
Authors: Ozório Maíza S , Rubira Rafael J G , Vieira Douglas H , Martin Cibely S , Constantino Carlos J L
Published: October 2023

The use of electrolyte-gated transistors (EGTs) as sensors can be an advantageous alternative for the detection of anionic molecules due to their capability to detect various ions in solution. In this study, we explore the potential of EGTs as analytical tools for detecting anionic molecules, utilizing a copper phthalocyanine-3,4′,4″,4‴-tetrasulfonic acid tetrasodium salt (CuTsPc) solution as a proof of concept. The results demonstrate the EGT’s capacity in detecting CuTsPc in an aqueous solution, which molecule dissociates into sodium ions (Na+) and CuPc(SO3
−)4 ions, leading to high ionic conductivity and the formation of electrical double layers (EDLs). Varying the concentration of the molecule induced alterations in the EDLs, exhibiting good linearity and sensitivity in the transconductance, and a detection limit of 6.0 × 10−8 mol l−1. Transistors employing the CuTsPc solution as electrolyte operated at low voltages and performed better than water-gated transistors (W-GTs). The transconductance (gm
) value for EGTs using CuTsPc solution reached 1.93 mS, while for W-GTs it was around 0.10 mS. Thus, the CuTsPc solution not only serves as a target-molecule in sensor measurements, but also demonstrates potential as an electrolyte in EGTs, thereby assuming a dual role within the device. The main advantage of the EGTs as an analytical tool is their use as a multiparameter device that enables the detection of the analytes using different phenomena that occur at the EDLs interface and which, consequently, changes the device’s performance.
Research on the service condition monitoring method of rolling bearings based on adaptive deconvolution and transformer
Authors: Zhang Yanfei , Liu Yang , Wang Lijie , Zhang Haipeng , Zhu Qianxiang , Kong Lingfei
Published: October 2023

Aiming at the complexity of the rolling bearing operation state in actual working conditions and the limitation of the feature extraction capability of single-scale model, this paper proposes a fault diagnosis method based on two-channel adaptive deconvolution and transformer module (TADAT). First, a frequency domain dataset is built and multiscale feature information is extracted using two-channel adaptive deconvolution at the beginning stage of the model; the global features of the signal are further extracted by combining them in series with the transformer (multi-head attention). Next, the loss function is optimized by introducing a regularized loss function with label smoothing and L2 regularization penalty term. Finally, the model is validated against an open-source dataset and operating condition data collected from an unbalanced bearing load test bed with an accuracy of over 98.5%. The model also maintains high accuracy under noisy samples. The test shows that the rolling bearing service condition monitoring method based on TADAT feature extraction model proposed by this method is characterized by simple model structure, high diagnostic accuracy and strong generalization performance, which provides a useful reference for the research of rolling bearing service condition monitoring.
Measurement and reduction of Ar metastable densities by nitrogen admixing in electron beam-generated plasmas
Authors: Yatom Shurik , Chopra Nirbhav , Kondeti Santosh , Petrova Tzvetelina B , Raitses Yevgeny , Boris David R , Johnson Michael J , Walton Scott G
Published: October 2023

Electron beam (e-beam) generated plasmas are useful for material processing applications such as deposition and etching because the plasmas deliver a large fluence of very low energy of ions to surfaces. Metastable species produced in the beam-region can also transport significant energy to the plasma periphery and surfaces. In this work, we have investigated the spatially resolved density of metastable Ar 1s5 species produced in an Ar and Ar/N2 e-beam generated plasma at pressures of 60–67 mTorr using laser-induced fluorescence (LIF). The experiments provide the first direct measure of absolute density and reduction of Ar 1s5 in an e-beam generated plasma when argon is diluted with nitrogen. These results are consistent with previous predictions of numerical modeling and measurements using optical emission spectroscopy. The present spatially resolved LIF measurements directly quantify the reduction of Ar 1s5 in the e-beam generated plasma by nitrogen admixing. This reduction was observed in the region of the electron beam and in the plasma periphery, where substrates are usually placed. For example, up to a threefold reduction of the density of Ar 1s5 was measured when the argon background was diluted with 15.5% nitrogen at pressure of 60 mTorr. Ar 1s5 reduction is attributed to excitation exchange with nitrogen molecules as well as the cooling of plasma electrons via inelastic collisions with nitrogen molecules.
High performance SAW resonator with spurious mode suppression using double-layer electrode transverse modulation
Authors: Zhang Shengkuo , Wang Hongliang , Zhang Peng , Cao Gang
Published: October 2023

This work aims to solve the problem of tradeoff between various properties and spurious mode suppression in surface acoustic wave (SAW) resonators. A high-angle rotated Y-cut LiNbO3 (LN)/SiO2/Si multilayered structure was proposed to balance the electromechanical coupling coefficient (K
2) and temperature coefficient of frequency (TCF), and the propagation characteristics of Rayleigh mode were simulated by the finite element method. For the widely existing spurious modes, the shear-horizontal wave and longitudinal modes were eliminated by optimizing the cut angle of LN and electrode thickness, and a method of double-layer electrode transverse modulation was proposed to suppress the transverse modes. This method reduces the mass loading effect by replacing the electrode from Cu to Cu/Al. Moreover, the Al thicknesses in different regions are changed to perform the transverse modulation, and thus a widespread suppression of transverse modes is achieved by exciting the piston mode and enhancing the energy constraint, with a significant improvement on quality factor at the resonance frequency. Eventually, the spurious-free SAW resonator has the K
2 of 9.5% and the TCF close to zero. This work provides a feasible scheme for the design of high performance SAW resonators with spurious mode suppression.
Transduction modality near instability in domain engineered relaxor ferroelectric single crystals
Authors: Finkel Peter , Lynch Chris , Amin Ahmed
Published: October 2023

A transduction modality based on inter-ferroelectric (FE) transitions in domain engineered single crystals, poised near an instability via mechanical clamping is reviewed. The phase transition is associated with strain levels that are much higher than what could be achieved using the linear piezoelectric mode. They are also accessible at significantly lower drive fields compared to the free state. The large FE–FE polarization change accompanying the phase switching has been utilized to demonstrate the vast electromechanical and thermal energy conversion capabilities of this sensing modality. The harvested mechanical energy density per cycle is nearly two orders of magnitude larger than that of linear piezoelectric bimorphs operating in a resonance-mode. Additionally, being a non-resonant modality, the problems associated with matching the harvester’s frequency to that of the structure (for maximum output) are obviated. Magnetoelectric energy harvesters and sensors have demonstrated similarly large coefficients. Compact broadband sound projectors fabricated using this modality have delivered 10–15 dB more source level over two and half octaves compared to the linear piezoelectric mode counterpart. Ongoing research in utilizing this modality in electro-optic modulation is discussed. Advances that have occurred over the last decade in fundamental understanding of this transduction modality and device physics are presented. It is our intent that this up-to-date review will stimulate interest in the applied physics community to further explore the benefits of this transduction modality. This review also summarizes fundamental knowledge gained of relevant issues. The focus of this review is on single crystals and thus the recent work on lead free ceramics is not addressed.
Accessing inaccessible information via quantum indistinguishability
Authors: Horvat Sebastian , Dakić Borivoje
Published: October 2023

In this paper we present and analyze an information-theoretic task that consists in learning a bit of information by spatially moving the ‘target’ particle that encodes it. We show that, on one hand, the task can be solved with the use of additional independently prepared quantum particles, only if these are indistinguishable from the target particle. On the other hand, the task can be solved with the use of distinguishable quantum particles, only if they are entangled with the target particle. Our task thus provides a new example in which the entanglement apparently inherent to independently prepared indistinguishable quantum particles is put into use for information processing. Importantly, a novelty of our protocol lies in that it does not require any spatial overlap between the involved particles. Besides analyzing the class of quantum-mechanical protocols that solve our task, we gesture towards possible ways of generalizing our results and of applying them in cryptography.
Well-matched PANI@FePO4@FeSi hybrid composite with excellent microwave absorption property
Authors: Li Chen , Deng Lianwen , Yan Tianyi , Huang Shengxiang , Peng Sen , Qiu Leilei , Wu Qizhao
Published: October 2023

PANI@FePO4@FeSi composites were prepared by one-pot synthesis. The PANI@FePO4 coating layer can effectively enhance magnetic loss, dielectric losses, and improve impedance matching by reduce the skin effect. The optimized reflection loss (RL) of the composites is −54 dB at 15.76 GHz with the absorption bandwidth (RL<−10 dB) of 2.7 GHz (14.3−17 GHz).Density functional theory (DFT) and ANSYS High-Frequency Structure Simulator (HFSS) analysis results suggest that destruction of local microstructural symmetry and inducing additional electric dipoles at the interface of each component. The density of state (DOS) of p orbital near the Fermi level decreases. Thus, dipole oscillation and polarization loss get enhanced under the external electromagnetic field. This work provides an avenue for designing new microwave absorbers.
Synthesis of polyaniline/spinel ferrites core-shell nanocomposites via sucrose auto-combustion and in situ polymerization
Authors: Gabal M A , Al-Mutairi Ebtesam , Angari Y M Al , Awad A , Al-Juaid A A , Saeed Abdu
Published: October 2023

Herein, we prepared new nanocomposites from polyaniline (PANI) as a conductive polymer, and ferrites, MFe2O4 (M = Co2+, Cu2+, Mg2+, Ni2+, and Zn2+), as metal-oxide ceramics using sucrose sol–gel auto-combustion and in situ of polymerization. The prepared nanocomposites’ structural, thermal, magnetic, and electrical/dielectric characteristics were investigated. X-ray diffraction (XRD) revealed the formation of the metal-oxide ceramics with weak crystallinity due to their coating in the amorphous structure of the PANI matrix. Transmission electron microscopy (TEM) images exhibited the wrapping of the entire metal-oxide ceramic particles by the PANI matrix, thus confirming the core–shell structure formation. Vibrating sample magnetometer (VSM) results showed drastic reductions in all ferrites’ magnetization by their inclusion in the non-magnetic PANI matrix. The measured coercivity values showed a noticeable lowering in the presence of PANI. Besides, the thermogravimetric analysis (TG) technique indicated apparent increases in the thermal stability of the prepared nanocomposites compared to the pure PANI. Moreover, the electrical conductivity results indicated a change from metallic-like behavior for the pure PANI to the semiconductor by including the ferrites. Furthermore, by comparing the pure PANI, the dielectric properties of nanocomposites increased by the presence of ferrites, suggesting the suitability of the entire nanocomposites to be used in energy storage devices such as capacitors.
Microstructure, multi-phase and corrosion resistance of amorphous phase reinforced multi-layer fabricated by laser beam
Authors: Li Jianing , Xu Lianyong
Published: October 2023

The Fe-Cr-B-Si deposited layers were prepared on the titanium alloy by the laser melting deposition (LMD) or the laser cladding (LC) technology. The microstructure of the clad layer and the deposition bulk was characterized by the scanning electron microscopy, transmission electron microscopy and electron-backscattered diffraction. The single clad layer was primarily composed of the amorphous phase (APs), the fraction of APs decreased with increasing of the LMD layer thickness due to the heat accumulation, producing the crystalline phases. Parts of the nanocrystalline phases (NPs) were produced due to the characteristics of a laser-induced pool (LIP), producing the deposition bulk with the good metallurgy bond between the adjacent laser fabricated layers. The corrosion resistance of the deposition bulk was enhanced due to the production of the oxides and hydroxides, forming a passive film to enhance the corrosion resistance.
High kinetic inductance NbTiN films for quantum limited travelling wave parametric amplifiers
Authors: Mantegazzini F , Ahrens F , Borghesi M , Falferi P , Fasolo L , Faverzani M , Ferri E , Labranca D , Margesin B , Mezzena R , Moretti R , Nucciotti A , Origo L , Vinante A , Zannoni M , Giachero A
Published: October 2023

A wide-bandwidth and low-noise amplification chain in the microwave regime is crucial for the efficient read-out of quantum systems based on superconducting detectors, such as Microwave Kinetic Inductance Detectors (MKIDs), Transition Edge Sensors (TESs), Magnetic Microcalorimeters (MMCs), and RF cavities, as well as qubits. Kinetic Inductance Travelling Wave Parametric Amplifiers (KI-TWPAs) operated in a three-wave mixing fashion have demonstrated exceptional dynamic range and low-noise performance, approaching the quantum limit. These amplifiers can be fabricated using a single layer of a high kinetic inductance film as weakly dispersive artificial transmission lines, with the ability to control the phase-matched bandwidth through dispersion engineering. In this study, we present the optimisation of the rf sputter-deposition process of NbTiN films using a Nb80%Ti20% target, with the goal of achieving precise control over film characteristics, resulting in high kinetic inductance while maintaining a high transition temperature. The parameter landscape related to the different sputtering conditions, such as pressure, power, and nitrogen flow, has been explored and the film thickness has been used as a fine-tuning parameter to adjust the properties of the final NbTiN films used for the fabrication of KI-TWPAs. As a final result, we have obtained a NbTiN film with a kinetic inductance of 8.5 pH/sq which we have exploited to fabricate KI-TWPA prototype devices, showing promising amplification performance.
A novel chaotic map-based encryption scheme for surveillance videos
Authors: Dhingra Deepti , Dua Mohit
Published: October 2023

The widespread use of surveillance cameras has initiated privacy concerns among individuals being captured by these devices. Due to the limited internal storage capacity, these cameras often transmit recorded videos over unreliable networks. This situation creates opportunities for attackers to exploit vulnerabilities, such as launching Man-in-the-Middle attacks, replayed scene attacks, and tampering with the video content. Considering these risks, this paper introduces a new chaotic map-based encryption scheme for surveillance videos. The work proposes a novel chaotic map using cascading and coupling operations on functions and is referred to as a Cascaded Coupled Logistic-Sine-Cosine (CCLSC) map. The chaotic performance of the novel CCLSC map has been evaluated using the Lyapunov exponent and the Bifurcation diagram. The scheme to encrypt surveillance videos is designed using the novel CCLSC map and our earlier designed Sine-Tangent-Sine (STS) chaotic map. The process involves extracting individual frames from the video and subsequently encrypts each frame as a digital image. The encryption of each frame involves three steps. The first step generates a Dynamic Chaotic Matrix (DCM) using CCLSC and STS map. The second phase is pixel scrambling using DCM and the final step changes the pixel values using DCM. Our results validate the security, robustness, and effectiveness of the proposed method.
Spinning primordial black holes formed during a matter-dominated era
Authors: de Jong Eloy , Aurrekoetxea Josu C. , Lim Eugene A. , França Tiago
Published: October 2023

We study the formation of spinning primordial black holes during an early matter-dominated era. Using non-linear 3+1D general relativistic simulations, we compute the efficiency of mass and angular momentum transfer in the process, which we find to be 𝒪(10%) and 𝒪(5%), respectively. We show that subsequent evolution is important due to the seed PBH accreting non-rotating matter from the background, which decreases the dimensionless spin. Unless the matter era is short, we argue that the final dimensionless spin will be negligible.
Radiation Spectral Analysis of 3D Dust Molecular Clusters (PAHs) and Peptoids under Ionization and Electric Field in ISM
Authors: Wu Ruiqing , Zhu Chunhua , Lü Guoliang , Zhang Xiaojiao , Lu Xizhen , Yu Jinlong , Chen Wujin , Long Mengqiu
Published: October 2023

Polycyclic aromatic hydrocarbons (PAHs), PANHs, and peptoids dust spectral calculations from the interstellar medium (ISM) are important for dust observations and theory. Our goal is to calculate the radiation spectrum of spherical PAHs dust clusters in a vacuum containing ionized and applied in the presence of an electric field. We propose a new simple computational model to calculate the size of three-dimensional spherical dust clusters formed by different initial dust structures. By the Vienna Ab-initio Simulation Package code, the density functional theory with the generalized approximation was used to calculate the electron density gradient and obtain the radiation spectrum of dust. When the radius of spherical dust clusters is ∼[0.009–0.042] μm, the dust radiation spectrum agrees well with the Z = 0.02 mMMP stellar spectra, and the PAHs radiation spectrum of NGC 4676 at wavelengths of (0–5] μm and (5–10] μm, respectively. In the ionized state, the N-PAH, C10H9N, 2(C4H 4)1+, and peptoids 4(CHON), (C8H10N2O5)1+ dust clusters at 3.3 μm, while the 2(C22H21N3O 2)1+, 4(CHON) dust clusters at 5.2 μm have obvious peaks. There is a characteristic of part of PAHs and peptoids clusters radiation at the near-infrared wavelength of 2 μm. However, especially after applying an electric field to the dust, the emission spectrum of the dust increases significantly in the radiation wavelength range [3–10] μm. Consequently, the dust clusters of PAHs, PANHs, and peptoids of the radius size ∼[0.009–0.042] μm are likely to exist in the ISM.
Depositional Architecture and Reservoir Quality Assessment of Abu Roash (G) Dolomite, as a Low Resistivity Pay, Razzak Oilfield, Western Desert, Egypt.
Authors: Abu Shady A , Fekry Mena , Elsayed M , Durocher Scott , Ali Rushdy A
Published: October 2023

Abu-Roash (G) dolomite (A/R-G) is considered one of the most prolific oil-bearing reservoirs in the Western desert. In this study, Razzak Oilfield was selected to investigate the geological and petrophysical findings of these successions that were assigned stratigraphically to the upper Cretaceous (Late Cenomanian), in the Alamein basin. Sedimentologically, three main facies groups have been recognized in the studied successions of A/R-G and include dolostone, limestone and mudstone facies; and depositional; are divided into three parts: A) Back-reef to reef crest (Reefal depositional setting) - dolostone facies group; graded to B) Inner-ramp of limestone / dolomitic limestone facies types; then C) mud-flat (intertidal setting) of calcareous mudstone facies type. Petrophysically, most of the recorded pore sizes in the dolomite zone are mesopores (≈1 micron), with scattered macropores (2-10 microns), as identified by MICP on some selected 1.5” core plugs. In general; A/R-G dolomite displays low resistivity pay (high conductivity) due to: A) The heterogeneity of moldic and vuggy pore size distributions (macropores); associated with the dominant intercrystalline-dolomite mesopores; and B) Fe-rich minerals that increase the conductivity; where most of the identified dolomite crystals are secondary, late-diagenetic stage ferroan dolomite; and confirmed that petrographically by thin-section analysis.
Analysis of the Reasons for Shutdown of Wells During the Stable Production Stage of Low-pressure and Low-permeability Gas Field Development
Authors: Wei-shi Zheng
Published: October 2023

With the extension of the development time of the Sulige gas field, the stage of increasing reserves and production has entered a stable production stage. The number of shut down wells is increasing, and the impact on production is also increasing, which is extremely unfavorable for the stable production of the gas field. Therefore, strengthening the management of shut down wells is becoming increasingly important. This article collects, organizes, and analyzes data from 202 shut down wells in the central region of the Sulige gas field based on geological understanding of the reservoir, fluid composition, logging data, water gas ratio, and gas production profile testing. The results show that wellbore fluid accumulation and water lock damage, wellbore scaling, energy depletion, poor reservoir properties, and throttle failure are the main factors causing shut down wells, This provides an important reference basis for formulating production resumption measures and gas increase targets for shut down wells.
Study on Simulation for Erosion-Corrosion in Petrochemical Process Piping
Authors: Liu Wencai , Li Yajun , Tong Gen , Zhang Minhui
Published: October 2023

Erosion-corrosion is a damage to metal caused by relative motion at high velocity between metal surface and erosive/corrosive fluid, resulting from combined actions by mechanical erosion and electrochemical corrosion. Since petrochemical plants install numerous process pipes, especially involving complex oil refining processes and multi-phase transformation between solid, liquid and gas, the erosion-corrosion becomes one of major problems that disturb industrial work safety. So, it is important to create a mechanistic simulation model by fully considering various factors and closely simulating erosion-corrosion process.
Function Optimization of Self-shutoff Protection System for -Valve Chambers of Long-distance Natural Gas Pipelines
Authors: Gao Yiran , Yuan Yundong , Zhou Xiang , Yang Jingwei , Lin Qi
Published: October 2023

The rate of pressure drop set value of shut-off valve in gas pipeline is uncertain to a certain extent, and the function of self-shutoff protection may disable under some leakage conditions. A gas pipeline leakage model is established using simulation software, to simulate the leakage, flow rate reduction, and crossover, and obtain the pressure changes in upstream and downstream shut-off valve chambers under different working conditions[1]-[3]. The rate of pressure drop is calculated by using the rate of pressure drop algorithm adopted by Line Guard 2300 system. Simulation results indicate that the gas transmission volume has little influence on the rate of pressure drop, and the leakage diameter has great influence on the rate of pressure drop, showing a positive correlation. When the pipeline runs in parallel, it is necessary to avoid opening the crossover valve under large pressure difference. Finally, the recommended rate of pressure drop threshold at the trunk line shut-off valve chamber is given, and the leakage condition of 1/2 diameter at 32km upstream can be detected under this recommended value.The simulation software is first applied in multinational pipelines, which can effectively protect pipeline defect points. Reduced methane cold venting, greatly improving the contribution to achieving emission reduction goals.
Corrosion Analysis and Prevention of Tubing Nipples in Four Wells
Authors: Hu Fang-ting , Liu Hong-tao , Zhao Mi-feng , Geng Hai-long , Xiong Mao-xian , Lou Er-biao
Published: October 2023

A high-temperature and high-pressure gas field in an oil field requires the use of super 13 chromium material due to corrosive environments. In the recent production process, there have been four consecutive cases of corrosion, fracture, and perforation of tubing nipples, which have brought enormous economic losses to the oilfield. This article analyzes the failure causes of these four tubing nipples and proposes preventive measures. In this paper, the macroscopic morphology, chemical composition, mechanical properties, metallography, and microscopic morphology of four failed tubing nipples have been analyzed. Combined with the field service conditions and string structure of the tubing nipples, it is believed that the failure of the tubing nipples is mainly due to the connection of carbon steel and stainless steel materials, forming a typical galvanic corrosion galvanic cell. The geometric and environmental factors of the materials exacerbate this corrosion. Eventually, severe galvanic corrosion occurred on the inner surface of the tubing nipple, resulting in severe wall thinning or partial perforation, and four tubing nipples failed. The failed tubing nipples in Wells A, B, and C have erosion marks, which are caused by the action of high pressure and high flow rate fluids in the well; The inner surface of the tubing nipple in Well D is rusty yellow, mainly due to the corrosion of its inner wall caused by the acid fracturing fluid injected earlier. At the same time, the string structure of four wells shows that the tubing nipple is located at the variable diameter node of the string. When the fluid in the well flows from the large hole into the smaller hole, the fluid in the well will change there, and its flow rate and pressure will also increase, further exacerbating the erosion in this area. With the development of deep wells containing carbon dioxide in oil fields and the application of carbon dioxide injection secondary oil recovery technology, the use of 13Cr martensitic stainless steel is also increasing. In order to avoid the occurrence of similar accidents that will bring huge economic losses to the oil field, it is recommended that the material of the pipe string (including accessories) of such wells be confirmed using a portable direct reading spectrometer before entering the well.
Numerical Simulation Study on Parameter Optimization of In-depth Fluid Diversion in Low-permeability Fractured Reservoir
Authors: Zhou Wei , Yin Daiyin
Published: October 2023

Daqing Chaoyanggou Oil Field is a low-permeability fractured oil reservoir that has entered into the middle and high water-cut periods of waterflooding extraction. Now, the moisture content is 74.88% and the injected water flows along fractures. The moisture content of oil wells increases quickly, accompanied with relatively serious invalid waterflooding. The in-depth fluid diversion can be used to exploit residual oil in substrate effectively and thereby increase recovery efficiency of the low-permeability fractured oil reservoir. In this study, parameters of in-depth fluid diversion in low-permeability fractured reservoirs can be optimized by numerical simulation method. According to geologic characteristics and fracture development situations in the study area, a geologic model of the study area was constructed. A historical fitting of exploitation indexes was carried out to optimize the dosage, injection rate and injection time of control-displacement agent during in-depth fluid diversion. Results demonstrated that the optimal dosage, the optimal injection rate and the optimal injection time of the control-displacement agent were 0.1 ∼ 0.15PV, 0.03 ∼ 0.04PV/a and about 70% of comprehensive moisture content, respectively. This study can provide reference to residual oil recovery in low-permeability fractured reservoirs during middle and high water-cut periods.
Numerical Simulation Study of Creeping Rock Formation in Jin X Fracture Block of Jingqiu Oilfield
Authors: Li Peng-wei , Ru Da-jun , Wang Jian-ning , Yang Li-gong , Ye Yong-sheng , Zhang Bo , Ma Chao
Published: October 2023

The Jin X fault block in Jing qiu Oilfield, as the main oil producing area of Huabei Oilfield.At present, there are a total of 141 wells drilled in this block, and 97 wells with damaged casing have been transformed;The casing transformation of wells has led to an increase in abandoned wells in this block, resulting in serious damage to the well network. The JinX fault block has a large number of damaged wells. The number of abandoned wells in this area has increased due to casing deformation, resulting in severe damage to the well network and high degree of casing damage. Among them,71 wells have been severely damaged due to casing deformation, such as scrapping, channeling, and pipe sticking, which have affected production, accounting for 73.2%. This has seriously affected the efficiency of oilfield production in the region.Previous statistics show that most of the casing deformation sections are in the paste salt formation, and the form of casing deformation and casing damage is mainly deformation. In order to investigate the mechanism of casing damage in the casing section, this paper establishes the creep equation of the casing layer in JinX block by conducting microstructure analysis of the casing layer and creep experiments in the casing layer, and then establishes a creep calculation model by using 3D numerical simulation technology, combining geological structure and well type conditions. The creep calculation model is then used to analyze the creep pattern under different conditions through simulation calculations, thus providing a reference for formulating effective casing loss prevention and control measures for the Jin X fault block.
Optimization Study of Injection-Production Parameters for CO2 Enhanced Oil Recovery and Storage in Low Permeability Oil Reservoirs
Authors: Yang Ze-peng , Liao Xin-wei , Wang Xiao-chen
Published: October 2023

To address the difficulty of water injection in the late stage of developing a certain low-permeability reservoir, CO2 injection and fracturing parameter optimization were conducted. The Latin hypercube sampling and numerical simulation methods were used to study the five-spot well network model established, and evaluate the impact of injection and fracturing parameters on oil recovery and CO2 storage using a comprehensive evaluation factor of oil displacement and storage. The results show that the injection rate is the main controlling factor affecting the oil recovery and storage effect, and the optimal injection rate is 6000m3/d. There is a certain contradiction between the oil recovery and storage objectives at different stages of injection development, but after ten years of injection development, the objectives of oil recovery and storage are consistent. The optimal combination of ijection and fracturing parameters yields a recovery rate of 72.54% and a CO2 storage amount of 101635.81 tons. This paper proposes that there is a certain contradiction between the oil recovery and storage objectives at different stages and evaluates schemes with different injection development periods by constructing a comprehensive evaluation factor for oil displacement and storage, which has certain reference value for optimizing parameters in the CO2 injection development of low-permeability reservoirs.
Study on scaling mechanism of injected water in Yujiaping Oilfield
Authors: Liu Gang , Li Shuo , Cheng Cheng
Published: October 2023

Oilfield injected water scaling often has a great impact on production and development. In this study, the scaling mechanism of injection well was studied, and the scale samples were analyzed by X-ray diffraction and other methods to determine the elements and mineral composition of scale samples and finally determine the main components of scale samples, providing a basis for subsequent water quality treatment. The results show that scale formation in Yu jia ping oil area is mainly caused by corrosion, inorganic salt scale caused by chemical reaction and sediment carried by injected water. Among them, inorganic salt scale is the main scaling component, and its main reason is the changes of ions in the injected water under different chemical environments. After a series of chemical and physical reactions, some ions in the injected water will form insoluble, insoluble and slightly soluble inorganic salts. After long-term accumulation, it is easy to form scale, namely the so-called inorganic salt scale. Inorganic salt scale is generally composed of sulfate and carbonate, the more typical calcium carbonate, calcium sulfate, barium sulfate, etc.
Development and Application of The Graft Coated Viscosity Reducer
Authors: Zhou Fei , Li Xue-liang , Yao Di , Sun Yi , Dong Wei , Wang Lei
Published: October 2023

The graft coated viscosity reducer was developed for the high cost of mixing light oil. The viscosity reducing mechanism is that the polar hypertonic agents in thSe viscosity reducer dissociate the net structures of the resin and asphalt and then form eutectic grafting with these dissociated macromolecules when the heavy oil in the water was broken or in the solution of associating state. The heavy oil takes shape of small particles while the resin is out of structure and not easy to get agglomerated. The released resin and the coating agent for the viscosity reducer form a layer of film on the surface of small oil particles to prevent the resin and asphalt from network structuring again. The heavy oil particles are not easy to be in coalescence concerning electrical repulsion and solution association among the coating in between. The heavy oil particles are dispersed in the medium to achieve the stabilization of viscosity reduction. For example, the viscosity of the crude oil from Liaohe Oilfield is 87.2mP•s after adding the agent at 50°C (the original viscosity was 4919mP•s). The viscosity reducer did not corrode the pipelines and wellbores and had no effect on the dehydration of united stations. The construction was carried out by continuously dripping the viscosity reducer into the 16 wells of Liaohe Oilfield. The viscosity all decreased to below 100mP•s afterwards. The current, load and other parameters all decreased along with the application. So this method could take the place of mixing light oil.
Study on Mechanical Calculation Method of Injection-production String in Changqing Gas Storage
Authors: Wang Chang-ling , Wang Rui-qi , Dong Zhao , Li Xu-mei , Ma De-hua , Wang Xiao-ming
Published: October 2023

on the basis of previous studies, According to the working conditions of injection and production wells in gas storage,this paper selects the mathematical model of the downhole string suitable for Changqing gas storage under the effects of piston, axial force, expansion, temperature and spiral bending. The mechanical analysis and calculation of injection-production string under simulated working condition and actual working condition are carried out by using corresponding mechanical analysis software, and the parameters such as the axial load, triaxial Factor of safety, minimum absolute triaxial Factor of safety, string elongation, string shortening are given, according to the calculation results, the safety strength of injection-production string is checked, and the load safety criterion for production and operation of string is given.Field Test and calculation of injection-production string are carried out. According to the actual test results, the deformation rule of the injection production string under the actual gas injection condition is summarized, and compared with the results calculated by the software, which verifies the accuracy of the calculating software and forms the method of the strength check of the injection and production string. It can provide effective evaluation means for the safe operation of injection and production string in gas storage. The safety failure of the injection and production pipe string is reduced, the safety and efficient operation of the gas storage is ensured.
A High Performance I/Q Zero-IF Mixer with IIP2 Calibration Technique in 45nm SOI CMOS
Authors: Li Jiayi , Wang Xinghua , Liu Zicheng , Ren Shiwei , Li Xiaoran
Published: October 2023

This paper presents a high performance I/Q zero intermediate frequency (IF) mixer with a second-order input intermodulation point (IIP2) calibration technique in 45nm SOI CMOS process. A behavioral model of the mixer is established to analyze the sources of the second-order intermodulation distortion (IMD2). Based on the analysis, a high accuracy load resistance modulation array is applied to achieve excellent IIP2 performance. The frequency of the local oscillator (LO) signal is 3.5GHz, while the RF input signal frequency range is 3.4GHz∼3.6GHz. Simulation results show that the proposed zero-IF mixer achieves a conversion gain of more than 9.2dB with the input 1dB compression point of -11.28dBm. Noise figure is about 16.9dB at 10kHz and lower than 11.6dB at the frequency above 1MHz. The IIP2 of the circuit is larger than 66dBm after the calibration, which increases more than 40dBm.
Prediction of ship trajectory based on deep learning
Authors: Li T , Li Y B
Published: October 2023

The rapid development of computer technology strongly promotes the study of maritime traffic safety. The application of artificial intelligence technology makes the ship’s trajectory prediction not limited to complex physical models, and improves the generality of ship’s track prediction. To address the problems of relatively poor prediction accuracy in existing ship trajectory prediction research and high coupling of algorithms during ship navigation while the prediction model needs to be improved, this paper combines grey forecast prediction model and long and short-term memory (LSTM) neural network to establish a neural network model for ship trajectory prediction. This model can effectively increase the number of messages in LSTM model, and reduce the loss value of the model and improve the accuracy of ship track prediction. The prediction method in this paper is verified by AIS data of a ship. The results show that compared with other time series prediction algorithms, this algorithm has higher prediction accuracy.
Satellite Return Link Resource Allocation Strategy Based on DVB-RCS2
Authors: Wang Yawen , Wu Chonghao , Ren Mingming , Zhou Yanan , Huang Cao , Luo Feiteng
Published: October 2023

This article improves the priority of the request queue packets for the Return Channel Satellite Terminal (RCST) of the Geosynchronous Earth Orbit (GEO) satellite system. It designs an inverted numbered slot tree resource allocation algorithm based on the Request Queue Maximum Weighted Delay Priority Algorithm (RQM-LWDF) in conjunction with existing slot allocation algorithms. It builds a simulation model of the DVB-RCS2 return link using the satellite communication module (SNS3) on the NS3 (Network Simulator 3) software simulation platform. It studies the throughput, packet loss rate, and delay performance of the algorithm under specific conditions and evaluates the algorithm.
A method for cross-correlation interference suppression of echo signal from external radiation source
Authors: Chen Sirui , Shang She
Published: October 2023

The features of the external radiation source radar result in the target echo power often being relatively low, and for the echo signal, the cross-correlation interference of the direct satellite signal causes the target echo to be undetected. This paper proposes a Q-way coherent-noncoherent accumulation method to suppress the inter-correlation interference from the radiation source direct signal without reconstructing all the direct signal eliminations, greatly reducing the amount of computation, for the suppression of inter-correlation interference and the correct detection of echoes provides a new idea.
Analysis and countermeasures of drilling challenges in complex ultra-deep exploration wells in thrust structural belt with multiple salt layers
Authors: Zhang Wei , Zhou Tuo , Jin Yulai , Xiao Yue , Li Hangyuan , Baletabieke Bahedaer , Gu Yixin
Published: October 2023

The deep and ultra-deep zones of Bokhtar oilfield in Tajikistan are the critical blocks for future exploration and development, which are imbedded between two salt layers, accompany with four reservoir and cap assemblages of middle and upper Jurassic, Lower Cretaceous, Upper Cretaceous and Paleogene. The reservoir and cap assemblages of pre-salt carbonate and salt-gypsum cap have great potential. The complicated geological structure, uncertain formation and non-developed pre-salt formations made the critical challenges for drilling operation, including: (1) The difficult casing program design caused by peripheral compression and thrust of the basin, the complicated geological structure, the large geological difference above and below the salt layer, the unfaithful prediction of multiple sets of salt layer, great formation pressure uncertainty, and many sealing points; (2) The upper salt formations are featured by developed thrust belt and large dip angle, the contradiction between deviation prevention and drilling acceleration in high steep structure is prominent, and the wellbore quality is difficult to control; (3) Due to the mud loss in upper salt layer, loss coexisted with blow out in the salt layer and inaccurate prediction of salt bottom, the drilling complexes such as mud loss, overflow and well collapse are occurred frequently; (4) Ultra-deep well depth (over 7000m), HTHP (180°C,140MPa), multiple salt layers and long open hole section made high requirements on high temperature resistance of drilling fluid, cementing slurry and downhole tools, as well as high drilling risk and cost. It is necessary to carry out the drilling difficulties investigation of ultra-deep exploration well under the consideration of pertinence, safety, applicability and economy, then formed the suitable drilling engineering plan for Bokhtar Block through the optimization of domestic and foreign advanced and mature deep and ultra-deep well technologies, which is used to provide the technical support for the first pre-salt ultra-deep exploration well in this Block to be drilled successfully.
Feasibility study on short radius sidetracking technology of old well in Hoja Gulluk Gas Field - A case study of H-1 well
Authors: Li Hangyuan , Zhou Tuo , Jin Yulai , Zhou Haiqiu , Xiao Yue , Gu Yixin , Baletabieke Bahedaer
Published: October 2023

The Hojaguruk block is located in the central and eastern region of the Amu Darya River. The reservoir is a hard carbonate reservoir with abnormally high pressure formation, which makes well control difficult. The reservoir is covered with a thick salt paste layer, and it is difficult to drill directional well in the salt paste layer. As the central and eastern parts of the right bank of the Amu Darya River enter the late stage of development, the production capacity of old lying Wells is insufficient and the reservoir energy power is reduced. Therefore, it is urgent to transform old Wells with short radius sidetracking drilling technology and revive lying Wells to improve the production of single well and achieve the goal of stable production and increase production. Based on a comprehensive analysis of the geological characteristics, development situation and technical difficulties of short radius sidetracking in the area where well H-1 is located, this paper analyzes and demonstrates the determination of the cutting point of sidetracking technology, the optimization of the well trajectory design scheme and the analysis and demonstration of the ultra-short radius sidetracking technology, and considers all factors comprehensively to study and determine that the ultra-short radius sidetracking technology is suitable for this well condition. It can meet the requirements of reservoir development design. It is suggested to carry out the key test of the ultra-short radius sidetracking technology, and promote the application in the developed blocks in the central and eastern part of the Amu Darya Project, so as to provide research ideas and directions for tapping the potential operations in other blocks.
Temporal trends in sociodemographic composition and land development within U.S. fenceline communities surrounding hazardous industrial facilities: 2001–2019
Authors: Southerland Veronica , Zota Ami R , Parasram Vidisha , Alvarez Camila , Clement Matthew , Anenberg Susan
Published: October 2023

Unintended releases from industrial facilities can expose fenceline communities to hazardous substances, and distance between facilities and nearby residential development can play a role in preventing exposures. Here, we assess trends in fenceline community sociodemographic characteristics, land development, and the association between the two using sociodemographic data for census tracts (n = 34 068) surrounding 2457 petroleum refining and chemical manufacturing facilities between 2001 and 2019. We find a higher median growth in percentage of Latinx populations among fenceline communities compared to neighboring communities with no industrial facilities. The increase in the median percentage of Latinx populations within fenceline communities was six times higher than for White populations overall (+6 and +1 percentage points, respectively). Though the percentage of the Black populations did not change within fenceline communities over this period, we find a minor sustained higher percentage of Black residents within fenceline communities relative to neighboring communities (20% versus 19%, respectively). Employing a spatial autoregressive model with autoregressive disturbances, we find that an increase in community percentage Latinx population is associated with a decrease in the rate of land development. Comparing fenceline and neighboring communities, we conclude that Black and Latinx populations are disproportionately located near industrial facilities, potentially contributing to inequitable exposure to unintended chemical releases. Our work lends support to the value of considering of sociodemographic composition of fenceline communities when evaluating industrial facility hazards.