bluuebunny/crossref_metadata_2025 huggingface dataset:
Exploring Magnetic and Electrical Brain Stimulation in Parkinsonian Dyskinetic Monkeys
Authors: Gouriou Estelle , Bourque Mélanie , Schneider Cyril , Di Paolo Thérèse
Published: November 2024

Background:

Parkinson’s disease (PD) chronic L-Dopa treatment often triggers motor complications, such as L-Dopa-induced dyskinesias (LID). LID are reported to be associated with abnormal glutamatergic activity between the striatum and primary motor cortex (M1), resulting in M1 hyperactivation. Beneficial noninvasive brain stimulation (NIBS) paradigms were reported to normalize glutamatergic activity. The objective of the present study was thus to set up a NIBS paradigm in parkinsonian monkeys to investigate motor behavior under basal conditions and with L-Dopa treatment-inducing dyskinesias.

Methods:

Motor behavior was investigated in five 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) dyskinetic female Macaca fascicularis monkey models of PD, allowing us to monitor the administration of NIBS and drugs. NIBS used were inhibitory protocols, that is, cathodal transcranial direct current stimulation (c-tDCS) and continuous theta-burst stimulation (cTBS). A procedure of three weeks was developed to progressively acclimate animals to the experimental conditions, equipment and noise of c-tDCS and cTBS before stimulating them with either vehicle or L-Dopa.

Results:

One session of c-tDCS with L-Dopa yielded no effect, whereas five sessions briefly reduced LID but decreased the duration of L-Dopa anti-PD effects. cTBS alone improved (decreased) parkinsonian scores as compared to sham stimulation or vehicle alone. Two sessions of cTBS with L-Dopa decreased LID without affecting L-Dopa anti-PD effects.

Conclusion:

This is the first study testing c-tDCS and cTBS on the motor behavior of MPTP dyskinetic monkeys. As compared to medicated patients, MPTP monkeys offer the opportunity to evaluate NIBS after-effects in drug-free and LID conditions, which are critical in the search for new PD treatment.
Predicted distribution of the endemic fern Elaphoglossum beddomei reveals threats to rainforests of Western Ghats of India
Authors: Thulasi R. , Munoz Francois , Sreekumar E.R. , Nair Maya C. , Rajesh K.P.
Published: November 2024

Pteridophytes are excellent ecological indicators of habitat quality. In this study, we built a model that predicts the habitat suitability of Elaphoglossum beddomei Sledge, an epiphytic or lithophytic and endemic pteridophyte in Southern Western Ghats, by using the technique of species distribution modelling. The occurrence data of E. beddomei from field explorations as well as from various herbaria were collected during 2018–2022. These occurrence data along with climatic data were processed by R packages. The processed data were further analysed using MaxEnt software to project the distribution of E. beddomei in future climatic scenarios. After correlation analysis, five bioclimatic variables – Mean Temperature of Wettest Quarter (bio8), Precipitation of Driest Quarter (bio17), Precipitation of Warmest Quarter (bio18), Precipitation of Wettest Quarter (bio16) and Temperature Annual Range (BIO5-BIO6) (bio7) – were selected from 19 bioclimatic variables with less correlation. Precipitation of Warmest Quarter (bio18) had the most influence in determining the distribution of E. beddomei, with a permutation importance of 83%. Conversely, Temperature Annual Range (BIO5-BIO6) (bio7) and Precipitation of Driest Quarter (bio17) showed least influence in determining the distribution of E. beddomei, and hence, the models created without these variables are considered for prediction. The habitat suitability predictions of the model indicate that the potential habitats of the species may get reduced in Southern Western Ghats in future climatic scenarios. It is in tune with the predicted expansion of drier climatic zones in Southern Western Ghats, which may reduce the suitable habitats for the E. beddomei in near future. So, it demands formulating suitable strategies for reducing the emission of greenhouse gases, regenerating forests and conserving forests by implementing more stringent policies on the environment to protect such highly habitat-specific evergreen elements.
Dynamic semantic networks for exploration of creative thinking
Authors: Georgiev Danko D. , Georgiev Georgi V.
Published: November 2024

Human creativity originates from brain cortical networks that are specialized in idea generation, processing, and evaluation. The concurrent verbalization of our inner thoughts during the execution of a design task enables the use of dynamic semantic networks as a tool for investigating, evaluating, and monitoring creative thought. The primary advantage of using lexical databases such as WordNet for reproducible information-theoretic quantification of convergence or divergence of design ideas in creative problem solving is the simultaneous handling of both words and meanings, which enables interpretation of the constructed dynamic semantic networks in terms of underlying functionally active brain cortical regions involved in concept comprehension and production. In this study, the quantitative dynamics of semantic measures computed with a moving time window is investigated empirically in the DTRS10 dataset with design review conversations and detected divergent thinking is shown to predict success of design ideas. Thus, dynamic semantic networks present an opportunity for real-time computer-assisted detection of critical events during creative problem solving, with the goal of employing this knowledge to artificially augment human creativity.
Human Cystic Echinococcosis Treated with Individualised Homoeopathy—A Case Report
Authors: Raizada Sonia , Shukla Indu
Published: November 2024

Cystic echinococcosis is a chronic, complex and neglected disease caused by the larval form of cestode Echinococcus granulosus. The liver is the most frequently parasitised organ in humans. Percutaneous drainage, systemic chemotherapy and surgery are the therapies available for hydatid cyst treatment where the risks associated with invasive procedures may be particularly high. Therefore, homoeopathic individualised treatment can be a better approach to treating cases of hydatid cysts without any side effects and risks. In the presented case, the patient received homoeopathic medicine Magnesium muriaticum based on individualisation and Medorrhinum as an intercurrent medicine. The homoeopathic treatment resulted in an overall improvement in the health of the patient. Serial ultrasounds also showed a reduction in the cyst size. This case highlights the fact that homoeopathy can be a plausible alternative to conventional treatment like surgery in cases of hydatid cysts along with improvement in the quality of life of patients as represented by EQ-5D-5L. The Modified Naranjo Criteria explicitly depict the potential causal relationship between the treatment and observed changes.
Assessing coastal aquifer vulnerability to seawater intrusion: adaptation of the DCG method and application to the Dradère–Souière coastal aquifer in northern Morocco
Authors: Bekkour Fouad , Amharref Mina , Es Saouini Hind , Acharki Siham , Bernoussi Abdes Samed
Published: November 2024

Context Seawater intrusion into coastal aquifers represents a major global environmental challenge, leading to salinisation of these water resources. Aims This study aims to protect coastal aquifers from marine salinisation by assessing their vulnerability to seawater intrusion. Methods The DCG method was adapted by considering the weighted sum of the following three critical parameters controlling seawater intrusion: distance from saltwater (D), aquifer hydraulic conductivity (C) and the hydraulic gradient (G). Thereby, the weights assigned to these parameters were objectively determined through sensitivity tests. Key results The DCG map of the Dradère–Souière coastal aquifer shows that vulnerability increases near the sea, with a high to extreme vulnerability zone extending parallel to the coastline up to 5000 m inland. These findings are corroborated by a correlation analysis with the electrical conductivity map. Conclusion This study highlighted the adaptation of the DCG method for assessing the vulnerability of coastal aquifers to seawater intrusion and its successful application to the Dradère–Souière coastal aquifer. Implications The DCG method could be extended to other coastal regions as a strategic tool for protecting against seawater intrusion. Further improvements could be achieved by correlating it with other approaches and integrating it with GIS technologies.
Implantable 3D printed hydrogels with intrinsic channels for liver tissue engineering
Authors: Lieberthal Tyler J. , Sahakyants Tatevik , Szabo-Wexler Naomi R. , Hancock Matthew J. , Spann Andrew P. , Oliver Mark S. , Grindy Scott C. , Neville Craig M. , Vacanti Joseph P.
Published: November 2024

This study presents the design, fabrication, and evaluation of a general platform for the creation of three-dimensional printed devices (3DPDs) for tissue engineering applications. As a demonstration, we modeled the liver with 3DPDs consisting of a pair of parallel millifluidic channels that function as portal-venous (PV) and hepatobiliary (HB) structures. Perfusion of medium or whole blood through the PV channel supports the hepatocyte-containing HB channel. Device computer-aided design was optimized for structural stability, after which 3DPDs were 3D printed in a polyethylene(glycol) diacrylate photoink by digital light processing and evaluated in vitro. The HB channels were subsequently seeded with hepatic cells suspended in a collagen hydrogel. Perfusion of 3DPDs in bioreactors enhanced the viability and function of rat hepatoma cells and were maintained over time, along with improved liver-specific functions. Similar results were observed with primary rat hepatocytes, including significant upregulation of cytochrome p450 activity. Additionally, coculture experiments involving primary rat hepatocytes, endothelial cells, and mesenchymal stem cells in 3DPDs showed enhanced viability, broad liver-specific gene expression, and histological features indicative of liver tissue architecture. In vivo implantation of 3DPDs in a rat renal shunt model demonstrated successful blood flow through the devices without clot formation and maintenance of cell viability. 3D printed designs can be scaled in 3D space, allowing for larger devices with increased cell mass. Overall, these findings highlight the potential of 3DPDs for clinical translation in hepatic support applications.
Fitness consequences of structural variation inferred from a House Finch pangenome
Authors: Fang Bohao , Edwards Scott V.
Published: November 2024

Genomic structural variants (SVs) play a crucial role in adaptive evolution, yet their average fitness effects and characterization with pangenome tools are understudied in wild animal populations. We constructed a pangenome for House Finches (
Haemorhous mexicanus
), a model for studies of host-pathogen coevolution, using long-read sequence data on 16 individuals (32 de novo
-
assembled haplotypes) and one outgroup. We identified 887,118 SVs larger than 50 base pairs, mostly (60%) involving repetitive elements, with reduced SV diversity in the eastern US as a result of its introduction by humans. The distribution of fitness effects of genome-wide SVs was estimated using maximum likelihood approaches and revealed that SVs in both coding and noncoding regions were on average more deleterious than smaller indels or single nucleotide polymorphisms. The reference-free pangenome facilitated identification of a > 10-My-old, 11-megabase-long pericentric inversion on chromosome 1. We found that the genotype frequencies of the inversion, estimated from 135 birds widely sampled temporally and geographically, increased steadily over the 25 y since House Finches were first exposed to the bacterial pathogen
Mycoplasma gallisepticum
and showed signatures of balancing selection, capturing genes related to immunity and telomerase activity. We also observed shorter telomeres in populations with a greater number of years exposure to
Mycoplasma
. Our study illustrates the utility of long-read sequencing and pangenome methods for understanding wild animal populations, estimating fitness effects of genome-wide SVs, and advancing our understanding of adaptive evolution through structural variation.
Tighter sum unitary uncertainty relation
Authors: Zhang Xia , Wang Xue , Ma Haitao , Liu Ming , Xing Junjing
Published: November 2024

Unitary uncertainty relations provide a theoretical framework that enhances our understanding of the principles underlying quantum mechanics and its applications in quantum information science. In this study, we derive both the unitary uncertainty relation and the weighted unitary uncertainty relation based on the sum variance for arbitrary pairs of unitary operators. By applying the arithmetic geometric mean inequality, we obtain a lower bound that is tighter than the one provided by Bagchi and Pati. [Physical Review A 94,042104] for two unitary operators. To illustrate our results, we include examples of both the unitary uncertainty relation and the weighted uncertainty relation based on sum variance.
Spontaneous symmetry breaking in two dimensions under non-equilibrium laminar flows
Authors: Minami Yuki , Nakano Hiroyoshi
Published: November 2024

We study the long-range order in two dimensions, where an order parameter is advected by laminar flows such as rotational, shear and elongational flows. Under these flows, we analyze the ordered state of the O(N) scalar model in the large-N limit. We show that the stability of the ordered state depends on the flow pattern; shear and elongational flows stabilize the long-range order but rotational flow does not. We discuss the physical mechanism underlying our results by connecting static correlations between fluctuations and their dynamics based on the interaction representation used in quantum mechanics. We find that advective transport induces superdiffusion under shear and elongational flows, thereby stabilizing the long-range order.
Research and Practice on EOR Development Strategy of Water Drive Followed by Gas Drive in Fractured Carbonate Reservoir in Bohai Sea
Authors: Li Tingli , Yuan Zhiqian , Zhang Zhang , Liu Chunyan , Zhang Mo
Published: November 2024

Focusing on the issues of high comprehensive water cut and low recovery degree following water flooding in the CFD 2-2 carbonate buried hill reservoir in the Bohai Sea, the productivity variation law, water cut rising characteristics and development effect of horizontal wells were analyzed based on different types of reservoir classification systems. The reservoir numerical simulation model of dual media coupling of matrix and fracture is established, and the analysis is done on the matrix and fracture production state, the distribution pattern of the residual oil, and the primary governing parameters.. The physical simulation experiment of water flooding to gas flooding is carried out. In conjunction with the distribution characteristics of fractures and matrix residual oil in low, middle and upper tiers of the framework, the development strategy of nitrogen injection pressure water cone in low water-flooded area, nitrogen flooding in middle inter-well residual oil enrichment area and nitrogen huff and puff in high well point residual oil enrichment area is put forward. The recovery rate is increased by 5-8 %, which successfully enhances the high water cut stage development effect, and provides reference for similar oilfield development.
The invention relates to a method for simulating phase permeability curve based on conventional logging data
Authors: Fu Yan , Xia Lian-jing , Shuo HU , Dong Li-jun , Ying DU , Cao Teng-fei , Zhang Li-li , Dai Ming-duo , Li Yi-xiao
Published: November 2024

Phase permeability curve is the curve of relative permeability (effective permeability/oil phase permeability in bound water) and water saturation change obtained through core phase permeability experiment. It is an indispensable data in oilfield development calculation, dynamic analysis, determination of oil-water saturation distribution in reservoirs and other water-driven oil related calculations, and an important index for reservoir evaluation. The study of effective permeability and relative permeability is of great significance for controlling the uniform advance of oil-water or oil-gas boundary and rationally developing oil and gas fields. The only effective way to study the phase infiltration is the core phase infiltration experiment, but the number of lithology samples is very limited, so the phase infiltration in oilfield development and application is still in the estimation stage, the accuracy is low, and the practical application is not strong. In order to improve the applicability of the phase permeability curve, it is necessary to establish a set of electrical interpretation methods associated with logging curves to realize electrical simulation instead of core measurement. In this paper, an electrical interpretation model of oil-water phase permeability is established based on flowable porosity and pore radius, and the effective seepage dynamic prediction and inversion of oil-water phase in each development stage of each reservoir is realized, which lays a solid foundation for the fine development of the reservoir.
Discussion on the Technology of Leak Prevention and Sealing in Drilling Engineering
Authors: Pengwei Li , Dajun Ru , Jianning Wang , Longfei Yin , Zhang Bo , Yongsheng Ye , Ligong Yang , Kang Yang
Published: November 2024

Lost circulation is one of the most serious and complex situations that affect the safety of drilling operations. The occurrence of lost circulation not only causes losses to drilling engineering, but also poses great difficulties for the exploration and development of oil and gas resources. Only by solving the problem of well leakage can drilling operations be carried out effectively and economically. Lost circulation can have a significant impact on exploration and development work. However, everything has two aspects. In the case of the same reservoir and leakage, once a well leakage is found, it indicates the appearance of an oil and gas reservoir, which is more common in fractured reservoirs. Therefore, in the expected drilling of reservoir sections, it is necessary to analyze and judge leaks well to avoid human error. Leakage can occur in shallow, medium, and deep layers, as well as in different geological epochs, such as from the Quaternary to the Paleozoic, and can occur in various rock formations. From the perspective of drilling, with long open holes, multiple pressure layers, and complex formations, especially when drilling adjustment wells, the problem of well leakage appears to be common and more serious, and the occurrence of well leakage will cause significant economic losses. So, we should prioritize prevention and try to avoid the occurrence of well leakage. If drilling is carried out in formations with well leakage, but appropriate drilling techniques and measures are taken, it is possible that well leakage will not occur, and at least the degree of leakage can be greatly reduced. In case of a well leakage, effective measures should be taken in a timely manner to block it and ensure the smooth progress of drilling. Therefore, the significance of researching leak prevention and plugging technology is significant.
Optimization of Rock Breaking Parameters by Combing Mechanical Specific Energy Theory and Random Forest Algorithm
Authors: Mu Hua-yan , Jiang Guan-cheng , Sun Jin-sheng , Dong Teng-fei , He Yin-bo
Published: November 2024

As the key indicators to evaluate drilling efficiency, mechanical rate of penetration (ROP) and mechanical specific energy (MSE) are affected by many uncertain factors. In the actual drilling process, it is often necessary to adjust the parameters to achieve speed and efficiency. A dual-objective model is established considering the maximization of ROP and the minimization of MSE. Which combined with the theory of mechanical specific energy and the principle of multi-objective optimization, the model parameter weights are determined by the feature importance in the random forest regression model, and the value range of rock breaking parameter is optimized, realize the fusion of physical model and data model. The results show that, in the four strata of well X, the average ROP of T2k1 stratum is increased by 48.6% and the average MSE is decreased by 26.6%, the average ROP of T1b3 stratum is increased by 89.9% and the average MSE is decreased by 33.8%, the average ROP of the T1b2 stratum was increased by 41.3% and the average MSE was decreased by 39.0%, the average ROP of the T1b1 stratum was increased by 29.2% and the average MSE was decreased by 37.3%, which met the dual objectives of maximizing the ROP and minimizing the MSE. Compared with the traditional single-objective optimization method, the established dual-objective model is more in line with the needs of complex drilling engineering, and the fusion of physical model and data model can reduce certain human error.
Research and Application of Plugging Drilling and Completion Technology for Difficult Old Well in Changchun Gas Storage
Authors: Qing Chuan , Zhang Xiaohui , Liu Changdong , Liu Qiang , Gong Hongzhe
Published: November 2024

Changchun Gas Storage has been included in the 14th Five-Year Plan for the development of petroleum and natural gas in Jilin Province. Its smooth construction and safe operation are crucial to ensure the stable supply of natural gas in Changchun. Well X106F located in the construction area was abandoned in 1988 due to drilling tool falling and multiple salvage failures. In order to ensure the sealing and integrity of the gas storage, it is necessary to effectively plug the drilling cover. In view of the problems of low well history accuracy, poor well wall stability and difficulty in cementing large boreholes, open hole drilling, trajectory design and control, film-forming and wall-fixing drilling fluid and prestressed cementing technologies are applied. By optimizing drilling tools, optimizing drilling parameters, designing the three-opening well structure and “five-section” profile, the plugging well construction requirements are met. The first and second open drilling along the old well borehole, 1313m deep on the first try to find top of the fish, after cementing plug, side tracking to 50m below the top of the fish and then cementing;for third spud control trajectory to accompanied the old well, according to the results of passive magnetic guidance, real-time adjustment of the trajectory scheme and construction plan, finally successfully collided with the old well at 1893m deep, after cementing the drilling plug, perforating and extruding cement, the cement job quality is good. The whole well construction period of 100 days, creating the fastest record of the old well plugging without trajectory of the fish type, providing technical support for the construction of Changchun gas storage, and providing experience for the same type of old well plugging and complex well treatment in China.
Application of Reservoir Blockage-relieving in Low Permeability Carbonate of Jingbian Gas-field
Authors: Hou Yi , Li Hao , Liu Ruchao , Zhang Peng , Zhang Anna Rui
Published: November 2024

Jingbian gas-field is a low-permeability and lithological gas reservoir with strong reservoir heterogeneity and poorly physical properties. As the gas-field is getting older and older, its gas wells start to produce less, and have growing difficulties to lift water and finally fail to work normally and steadily. One inborn factor lies in the unstable liquid composition of Jingbian gas-field: salty formation water with easy-fouling ions and acidic gas such as CO2 and H2S. Living in the underground for a long time these active materials prone to make the forming of water blocking and the solid deposition, which will weaken gas flow ability and threaten the production. After a detailed study on the plugging, there are three kinds of blocking divided: abruptly impurity blocking, slowly water locking, and energy deficiency. To relieve these blocking, methods have been put forth and carried out in field with achievement. The successful application has brought blockage gas wells solutions in Jingbian gas-field.
Study on Variability Production Characteristics of Fracturing Fluid Imbibition Displacement for Typical Shale
Authors: Zhu Xiu-Lan , Li Teng , Peng Xiang , Yang Zhen , Wang Qi-Xuan , Zhang Qing-Jiu
Published: November 2024

CO2 injection is a prominent measurement to enhance the recovery of shale reservoirs. The imbibition of fracturing fluid + CO2 additive is considered important for promoting the enhancement and stabilization of shale oil production to ensure energy supply. The imbibition experiments of fracturing fluid + CO2 additive were carried out in shale reservoirs with a nuclear magnetic resonance (NMR) test. The imbibition displacement characteristics at different pore scales of shale were quantitatively evaluated. The variability of the imbibition effects in shale reservoirs was clarified in terms of shale type, fracturing fluid type, and CO2 additive (pressure). This finding indicates that the effectiveness of the fracturing fluid + CO2 additive imbibition on shale reservoirs is stronger, and the imbibition displacement efficiency ranges from 33.38 % to 41.56 %. The imbibition contribution rate is considerably higher for small pores than for large pores, and the difference between them is more than 10%. Therefore, the imbibition of fracturing fluid + CO2 additive mainly extracted crude oil from the small pores of shale reservoirs. CNI nano variable-viscous slippery water is more effective for imbibition displacement in laminar type shale. For laminated type shale, EM30+ + guanidine gum mixed water has a better imbibition effect than CNI nano variable-viscous slippery water. Under 16 MPa CO2 + fracturing fluid (miscible states), the imbibition displacement efficiency of the shale is significantly enhanced. The imbibition displacement degree at different pore scales is also increased. For different types of shale reservoirs, the imbibition displacement degree at different pore scales would be improved by methods, including the optimization of the fracturing fluid or the change of imbibition conditions. This study presents a theoretical underpinning for the high-efficiency exploitation in shale reservoirs.
Feasibility Study on Infiltration of Sidetracking Horizontal Wells in Fuyu Tight Oil Field
Authors: Zheng Siqi
Published: November 2024

The Fuyu oil layer in well area 1 is a tight reservoir. Due to poor reservoir properties, conventional fracturing production wells have low production and rapid decline, with a recovery rate of only 2.22%.. Moreover, the surface of the well area is a wetland protection zone along the river. Under the new safety and environmental protection policies, new drilling is not allowed in the protection zone. In order to improve the development effect of the well area and increase the recovery rate, based on the geological and development characteristics of the oil reservoir, and in response to the problem of fast water breakthrough in east-west oil wells and ineffective water injection in non east-west oil wells in the Fuyu oil layer, the main oil layer with high well control degree, small well network density, and well-developed reservoir is selected. The original development well points are used to sidedrill stepped horizontal wells, combined with volume fracturing of tight oil horizontal wells, to avoid adjacent reserve losses, Exploring a new infill model for sidetracking horizontal wells in tight oil reservoirs in Fuyu, providing reference for effective development of similar reservoirs.
Design Method and Reliability Analysis of Deep Well Casing Strength
Authors: Yaxuan Wang , Jiayu He , Hongzhi Xue , Zhiyong Wei , Wang Lin , Weixing Zhu
Published: November 2024

With the development of the petroleum industry, more and more oil fields are beginning to engage in deep well exploration. Deep well casing is an important drilling equipment in oilfield development, which is a key factor in ensuring wellbore stability, maintaining production safety, and improving production capacity. However, due to the high requirements for equipment in drilling operations, problems in the design, manufacturing, and installation of deep well casing can easily lead to issues such as poor wellbore stability, oil leakage, and drilling accident safety. Therefore, the performance and reliability evaluation of deep well casing has become a key issue. This article summarizes the research progress of deep well casing strength design methods and reliability analysis through extensive research on existing literature. The main content includes the working principle, design standards, and advantages and disadvantages of different methods of deep well casing, aiming to provide reference for the design and use of deep well casing.
Experimental study on acidizing of natural gas hydrate reservoirs
Authors: Liu Pingli , Huang Qisheng , Du Juan , Shu Hui , Wang Ming
Published: November 2024

Natural gas hydrates (NGH) are a promising resource. Due to the weak cementation of hydrate reservoirs, the reservoirs are prone to sand production or destabilization during hydrate dissociation. Samples of hydrate sediments were manually prepared, consolidated using a cementing agent, and then subjected to flow experiments using an acid solution. Comparative experiments were also conducted with unconsolidated samples. The consolidation samples could maintain the skeleton morphology after acidizing, and no sand production was observed; the unconsolidated samples had severe skeleton deformation after acidizing and serious sand production. The permeability of the consolidation samples after acidizing was 2.95mD, and porosity increased by 8.56%; the permeability of the unconsolidated samples after acidizing was 1.26mD, and the porosity decreased by 7.45%. CT scan images and mercury intrusion curves show good pore development after acidizing the consolidation samples, while the unconsolidated samples have poor pore development and sand plugging after acidizing. This result is because the cementing agent can consolidate the sand and gravel so that it will not be dislodged and transported during the acidizing process, thus maintaining reservoir stability. This study demonstrates the feasibility of acid modification technology in hydrate reservoirs, which is informative for the safe development of gas hydrates.
A Deep Learning Structure Correction Method Under the Influence of Special Lithology Body
Authors: Jun Zhu , Yonglei Liu , Ning Yin , Jiawei Ren , Xiaochuan Yang , Wei Luo
Published: November 2024

In the process of precise exploration and development of oil and gas reservoirs, the accurate implementation of the target layer structure plays a vital role in the increase of oil reserves and the success of drilling. However, with the gradual deepening of the research, it is found that in the overlying strata of oil and gas reservoirs, special lithological bodies with strong heterogeneity and abnormal velocity are usually locally developed, which directly affects the construction of seismic data migration velocity, resulting in structural distortion at the local position of the reservoir in the process of data interpretation. Focusing on the structural change caused by the abnormal velocity, the deep learning algorithm is used to accurately predict the velocity of the special lithologic body and realize the accurate correction of the structure. Firstly, based on the combination of seismic and geological understanding, the geological model of the target layer and the overlying special lithologic body is constructed, and the distribution law of the special lithologic body is identified by the forward simulation method. Then use the well-side seismic trace and P-wave velocity curve to train the velocity data through the deep learning method and apply the training results to the post-stack seismic data to obtain the accurate P-wave velocity body. Finally, the real formation velocity over the target layer is restored to achieve reservoir structure correction. Based on this method, the research experiment was carried out in the M block of the Tarim Basin, and the spatial distribution range of the special lithology body was carved. The data error between the migration velocity body and the abnormal high-velocity body was calculated, and the target layer structure in the study area was corrected.
Application of Simul-frac technology in Longdong shale oil field
Authors: Che Haoyang , Bai Mingwei , Chai Long , Zuo Ting , Li Zefeng
Published: November 2024

This paper for the transformation of unconventional reservoir large-scale volume fracturing of long operation cycle, equipment occupancy, through the well optimization, fracturing design optimization, supporting equipment, construction organization mode upgrade, in the changqing oilfield longdong shale oil HX platform realized a single set of fracturing vehicle for two well synchronous shunt fracturing, created a single unit 17 hours fracturing 10 shale oil reservoir transformation new record. Compared with the production mode of two sets of fracturing units on the same platform, the efficiency of synchronous shunt fracturing operation of single unit increased by 32.1% and the number of equipment used decreased by 17.3%, which initially reflected the advantages of synchronous shunt fracturing technology in improving quality and efficiency. Through the output tracking analysis of the horizontal Wells of synchronous shunt fracturing transformation for half a year, the four Wells showed good transformation effect. Synchronous shunt fracturing technology in changqing oilfield shale oil platform successful application for the future unconventional oil and gas resources cluster well fracturing transformation speed to provide new ideas, the technology can improve the efficiency of oil service enterprises, reduce the completion cycle and comprehensive operation cost, for oilfield company, can quickly build production effect.
Difference of Sedimentary Characteristics and Main Controlling Factors Between Platform Margin Shoal and Ramp Shoal in M Formation of A Oilfield in The Middle East
Authors: Yu Yi-Chang , Shen Yi , Jing Xi , Xu Ya-Nan , Wang Yi-Fan , Guo Rui , Li Feng-Feng , Wang Jiu-Zhou
Published: November 2024

The bioclastic limestone reservoirs of M Formation in A Oilfield mainly develop in the ramp shoal and platform margin shoal, but the sedimentary characteristics, spatial distribution and main controlling factors of the two types of shoals are significantly different. Based on the data of seismic, well logging, core, casting thin sections and analytical tests, the comparative analyses of lithology, petrophysics and spatial distribution of the two types of shoals are carried out, and the control mechanism of relative sea level rise and fall and paleogeomorphology on their development is clarified. It is showed that the two types of shoals can be subdivided according to hydrodynamic conditions and bioclastic types. The platform margin shoals are dominated by grainstone and gravel limestone, and the bioclastics are mainly rudist and echinoderms. The logging curve is funnel-shaped, and the seismic is patchy distribution. In the vertical direction, the grain size of shoals becomes coarser, and the sedimentary sequence of medium energy shoal—medium-high energy shoal—high energy shoal is developed. In the horizontal direction, the facies belts of different shoals are narrow, and they are distributed quasi-layered semi-continuously around high energy shoals. The ramp shoals are dominated by packstone and grainstone, and the bioclastics are mainly non-fixed bivalves and algae. The logging curve is micro-tooth box-shaped, and the seismic is sheet distribution. In the vertical direction, the grain size change of shoals is not significant, and the sedimentary sequence of medium energy shoal—medium-high energy shoal is developed. In the horizontal direction, the facies belts of different shoals are wide, and they are distributed layered continuously around medium-high energy shoals. Relative sea level change controls the energy of sedimentary environment and the type of shoal facies, and the high position of paleogeomorphology controls the formation and distribution of high energy shoals. When the relative sea level is high and the paleogeomorphology is gentle, the ramp shoal is developed. As the relative sea level drops, the hydrodynamic condition increases, and the difference in the accumulation speed of different shoals enhances the fluctuation of the paleogeomorphology, the ramp shoal gradually transitions to the platform margin shoal. The above research can provide reference for the exploration and development of such reservoirs.
Study on the modularization of project operations under the “oil company” model
Authors: Hu Yue , Dai Cheng , Zhang Hao
Published: November 2024

A rational and efficient business management and operation model is a prerequisite for the smooth operation of an organization. This study aims to build an intensive and efficient business management model with the characteristics of the “oil company” model. Compared with the traditional business management model, the “oil company” model has significant advantages in terms of organizational structure, communication efficiency, work style and work efficiency, etc. Due to the compression of management levels and the shortening of business chains, the communication efficiency and work efficiency are higher, and the composition of personnel and work style are more flexible. Therefore, based on the theory of the “oil company” and on the idea of compressing management levels and shortening management chains, business management departments should be integrated, streamlined and optimized, and business chains should be sorted out.
Study on the Influence of Working Hours of Electronic Pressure Gauges on Measurement Accuracy
Authors: Wang Zhongliang
Published: November 2024

Electronic pressure gauge is a kind of well logging instrument for measuring downhole temperature and pressure accurately. Its high reliability and accuracy are widely used in well testing. With the oil field production entering the middle and late period, the requirement of well testing is increasing, and the daily calibration of electronic pressure gauge is put forward higher requirements. The measuring accuracy of the new electronic downhole pressure gauge is very high, but with the use of the instrument, the working time increases, the measuring accuracy of the electronic pressure gauge will gradually decline. In order to determine the effect of working time on the measuring accuracy of the electronic pressure gauge, a reasonable calibration period of the instrument is determined. Using mathematical statistics and function regression method, this paper analyzes the calibration data of the past two years, and obtains the factors that influence the measuring accuracy of the electronic pressure gauge. The results show that the measurement accuracy of the electronic pressure gauge decreases with the increase of its working time, and the change is obvious every four months. Through this conclusion, the optimal calibration period of the electronic pressure gauge can be determined, thus improving the measuring accuracy of the instrument, reducing the work intensity of the calibrator, making the downhole data more accurate, avoiding the invalidation of the measured data due to the error of the instrument, and saving manpower and material resources.
Research and Practice of Development Model during the Continental Heavy Oil Field’s Extra-high Water Cut Stage in the Bohai Sea
Authors: Li Tingli , Tan Jie , Yuan Zhiqian , Li Zijin , Ma Jiexi
Published: November 2024

The formation mechanism, production limits and injection-production pattern of residual oil were studied by laboratory experiment, micropore simulation and reservoir engineering. The findings indicate that when injection times increase, the displacement efficiency rises as well. The residual oil mostly remains in the pore throat, which has a radius of 10 to 50 μ m, with a mean pore throat radius of 35 μ m.. As the displacement pressure gradient increases from 0.004MPa/m to 0.012MPa/m, When the displacement ratio of piston type increases and the displacement ratio of water film flow drops, the displacement efficiency grows. The horizontal well pattern’s gradient of displacement pressure is increased by 1.5 ~ 1.7 times compared with the oriented well pattern, and the displacement efficiency is increased by 12% ~ 15%. The development of the Bohai oilfield during the ultra-high water cut stage has been informed by the aforementioned findings, forming a horizontal well joint directional well three-dimensional pattern development model, oil production rate increased from 1.3% to 2.3%, and water drive recovery rate increased from 24.5% to 38.6%, realizing efficient development in the ultra-high water cut stage, and providing reference for the development of similar oil fields.
Development of Intelligent Testing and Evaluation System for Fracturing Pump
Authors: Chen Bing-deng , Jin Ling , Zhang Na , Zhou Zhi-xiong , Han Xing , Bai Han-qin
Published: November 2024

Fracturing truck is the key technical equipment for oil and gas production stimulation. Fracturing pump of fracturing truck is subjected to high pressure load for a long time during use. Due to the influence of many factors such as transportation and equipment aging, the performance of fracturing pump in field use is reduced and the output power is insufficient. In order to realize the on-site inspection of fracturing pump, a set of intelligent inspection and evaluation system of fracturing pump is developed. Through the establishment of the hardware test platform and the development of the software system, the intelligent inspection and evaluation system of fracturing pump with the features of one-click automatic detection, automatic analysis of performance indicators, intelligent prediction and maintenance of health status is realized. The system can support the static pressure test, water power test and overpressure protection test of 140MPa ultra-high pressure fracturing pump. Experimental tests show that the test accuracy of the equipment can effectively meet the detection and evaluation needs of the field fracturing truck, ensure the normal function through static pressure and water power detection, and determine the safety of the equipment through overpressure protection detection, which greatly improves the effect and efficiency of fracturing operations.
Study on A New Type of High Temperature Resistant Adsorption Type Retarded Acid System
Authors: Zou Qi , Du Juan , Liu Pingli , Shi Yiquan , Lu Xiao , Xiao Yonghua
Published: November 2024

Deep carbonate reservoirs present significant hurdles for reservoir stimulation due to extreme temperatures and rapid acid-rock reactions. The dense adsorption layer has the ability to postpone the interaction between rock and hydrogen ions, which is crucial for lowering the acid rock reaction rate. Based on the surfactant and film-forming agent’s synergistic impact, the retarding agent SH-1—which has the ability to generate a dense adsorption film on the surface of rock samples—was chosen for this study. After adding synergist and corrosion inhibitor, a new type of high temperature resistant adsorption type retarding acid system ’ 0.9% SH-1 + 20% HCl + 0.1% synergist + 1.5% corrosion inhibitor ’ was developed. The retarding performance of the retarding acid system at high temperature and various parameters of acid rock reaction kinetics were studied. The results show that the new adsorption-type retarded acid system can achieve good retarding effect at high temperature and ultra-high temperature, and the retarding rate is 90 % at 180 °C. In comparison to traditional hydrochloric acid, the new adsorption-type retarded acid exhibits a lower hydrogen ion mass transfer rate and a higher acid-rock reaction activation energy. These differences can effectively lower the acid-rock reaction rate. Additionally, an examination of the etching morphology reveals that the retarded acid is more easily etched along the cracks leading to the deep core. The novel adsorption-delayed acid offers excellent retarding power, high temperature resistance, and minimal damage. Consequently, it has certain reference value for the study of acidification transformation of ultra-high temperature deep carbonate reservoirs.
Influence of Heterogeneous Reservoir on Carbon Sequestration and Carbon Displacement
Authors: Wang Xiao-chen , Wang Pei-jun , Cui Can , Fan Dalong , Huang Lin-gang , Tuluhon A-lidan
Published: November 2024

Carbon Capture, Utilization and Sequestration (CCUS) is a method of burying CO2 captured in various ways into the reservoir and extracting the remaining oil from the reservoir. It is one of the important methods to reduce carbon emissions and achieve carbon neutrality in the next few decades, and it is also considered to be the most economical and effective method to slow down the greenhouse effect. It is very important to study the influence of reservoir heterogeneity on CO2 storage and oil recovery in order to make CCUS scheme store more CO2 and recover more remaining oil. Firstly, the numerical simulation model of reservoir is established in this paper. Its injection-production mode is gas injection in vertical wells at the top of the reservoir at a fixed gas injection rate, and oil production in horizontal wells at the bottom of the reservoir at a fixed pressure. Secondly, the distribution of reservoir porosity and permeability is designed, and four reservoir models are established: homogeneous reservoir, heterogeneous reservoir, positive rhythm heterogeneous reservoir and reverse rhythm heterogeneous reservoir. Finally, the effects of four reservoir models on CO2 storage and oil recovery are studied, and the migration law of CO2 is comprehensively analyzed according to the characteristics of reservoir pressure distribution. The reverse rhythm reservoir has the best CO2 storage effect, and the positive rhythm reservoir has the highest oil recovery. That is, when burying is the main method, the reverse rhythm heterogeneous reservoir is preferred; When oil displacement is the main method, positive rhythm reservoir is preferred. Among the four homogeneous or heterogeneous reservoirs, the migration law of CO2 in reservoirs is quite different, mainly due to the influence of reservoir heterogeneity. CO2 preferentially migrates from the dominant channels in the reservoir, but regardless of the reservoir type, the molar fraction of CO2 at the top of the reservoir is the highest. In addition, the CO2 invasion of four kinds of reservoirs in different stages of caprock is analyzed and its safety is analyzed. This study provides an effective reference for the establishment of numerical simulation models of different types of heterogeneous reservoirs, the migration characteristics of carbon dioxide in reservoirs and the effective operation and evaluation of CCUS scheme.