Huiyan Zhao¹, Xuezhong Chen¹, Zhijian Hu^2,*, Man Chen¹, Bo Xiong³, Jianying Yang¹

FDMP-Fluid Dynamics & Materials Processing, Vol.20, No.6, pp. 1313-1330, 2024, DOI:10.32604/fdmp.2024.048840

Abstract Using the typical characteristics of multi-layered marine and continental transitional gas reservoirs as a basis, a model is developed to predict the related well production rate. This model relies on the fractal theory of tortuous capillary bundles and can take into account multiple gas flow mechanisms at the micrometer and nanometer scales, as well as the flow characteristics in different types of thin layers (tight sandstone gas, shale gas, and coalbed gas). Moreover, a source-sink function concept and a pressure drop superposition principle are utilized to introduce a coupled flow model in the reservoir. A… More > Graphic Abstract

Jianchao Shi^1,2, Yanan Zhang³, Wantao Liu^1,2, Yuliang Su^3,*, Jian Shi^1,2

FDMP-Fluid Dynamics & Materials Processing, Vol.20, No.5, pp. 1147-1163, 2024, DOI:10.32604/fdmp.2023.044500

Abstract Class III tight oil reservoirs have low porosity and permeability, which are often responsible for low production rates and limited recovery. Extensive repeated fracturing is a well-known technique to fix some of these issues. With such methods, existing fractures are refractured, and/or new fractures are created to facilitate communication with natural fractures. This study explored how different refracturing methods affect horizontal well fracture networks, with a special focus on morphology and related fluid flow changes. In particular, the study relied on the unconventional fracture model (UFM). The evolution of fracture morphology and flow field after More >

Fang Li^1,*, Juan Wu¹, Haiyong Yi², Lihong Wu², Lingyun Du¹, Yuan Zeng¹

FDMP-Fluid Dynamics & Materials Processing, Vol.20, No.5, pp. 1015-1030, 2024, DOI:10.32604/fdmp.2023.043256

Abstract Methods for horizontal well spacing calculation in tight gas reservoirs are still adversely affected by the complexity of related control factors, such as strong reservoir heterogeneity and seepage mechanisms. In this study, the stress sensitivity and threshold pressure gradient of various types of reservoirs are quantitatively evaluated through reservoir seepage experiments. On the basis of these experiments, a numerical simulation model (based on the special seepage mechanism) and an inverse dynamic reserve algorithm (with different equivalent drainage areas) were developed. The well spacing ranges of Classes I, II, and III wells in the Q gas More > Graphic Abstract

Yanqun Yu^1,*, Wenhao Xu¹, Yahui Huangfu¹, Jinhai Liu^1,2, Bensheng Wang¹, Kai Liu¹

Energy Engineering, Vol.121, No.6, pp. 1521-1533, 2024, DOI:10.32604/ee.2024.047986

Abstract China’s unconventional gas fields have a large number of low-productivity and low-efficiency wells, many of which are located in remote and environmentally harsh mountainous areas. To address the long-term stable production of these gas wells, plunger-lift technology plays an important role. In order to fully understand and accurately grasp the drainage and gas production mechanisms of plunger-lift, a mechanical model of plunger-liquid column uplift in the plunger-lift process was established, focusing on conventional plunger-lift systems and representative wellbore configurations in the Linxing region. The operating casing pressure of the plunger-lift process and the calculation method… More >

P. Pai Nityanand, B. Devaki, G. Bhat Pareekshith, V. S. Sampath Kumar^*

Frontiers in Heat and Mass Transfer, Vol.22, No.2, pp. 655-673, 2024, DOI:10.32604/fhmt.2024.050237

Abstract The study in this manuscript aims to analyse the impact of thermal radiation on the two-dimensional magnetohydrodynamic flow of upper convected Maxwell (UCM) fluid between parallel plates. The lower plate is porous and stationary, while the top plate is impermeable and moving. The equations that describe the flow are transformed into non-linear ordinary differential equations with boundary conditions by employing similarity transformations. The Homotopy Perturbation Method (HPM) is then employed to approach the obtained non-linear ordinary differential equations and get an approximate analytical solution. The analysis includes plotting the velocity profile for different Reynolds number… More >

Rebecca Y. M. Cheung^1,*, Iris Yili Wang², Elsa Ngar-Sze Lau³

International Journal of Mental Health Promotion, Vol.26, No.3, pp. 177-187, 2024, DOI:10.32604/ijmhp.2024.047190

Abstract Guided by the theoretical processes of mindfulness and psychological well-being, this study examined serenity as a mediator between mindfulness facets and psychological well-being, as indexed by depressive symptoms and life satisfaction. Participants were 133 mindfulness practitioners who took part in a 3-day transnational meditation event in Hong Kong. Upon informed consent, participants completed a self-report questionnaire. The findings from structural equation modeling showed that serenity mediated the relation between two facets of mindfulness, including describing and nonreacting to inner experience, and life satisfaction. Serenity also mediated the relation between the mindfulness facet of describing and More >

FATMA LOUZRI, SADJIA BENNOUR

Journal of Polymer Materials, Vol.37, No.1-2, pp. 55-76, 2020, DOI:10.32381/JPM.2020.37.1-2.5

Abstract Poly(N,N-dimethymethylacrylamide -co-crotonic acid) (P(DMA-CAx)) hydrogels were prepared by free radical polymerization, using N,N- methylenebisacrylamide (NMBA) as cross-linking agent. The synthesized hydrogels were characterized by Fourier transform infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA). The effects of comonomer composition and pH of the medium on the swelling behavior of hydrogels were investigated. The obtained results showed that the swelling capabilities of hydrogels increased as crotonic acid content and pH increased. In order to evaluate the controlled release potential of the polymeric matrix, it was loaded with potassium nitrate and ammonium nitrate as fertilizers and the release More >

DENIZ AKIN SAHBAZ^1,*, BETUL TURP KAYA²

Journal of Polymer Materials, Vol.38, No.3-4, pp. 247-256, 2021, DOI:10.32381/JPM.2021.38.3-4.6

Abstract The objective of this study is to develop chitosan-based films containing Hypericum perforatum L. and/or Citrus limon L. oils and to investigate their suitability as novel wound dressing materials. The morphology of the chitosan-based films were observed by means of employing the scanning electron microscopy (SEM) and the chemical structure characterization was performed via Fourier Transform Infrared Spectroscopy (FTIR). Hypericum perforatum L. and/or Citrus limon L. were successfully incorporated to the chitosan films. Antibacterial, swelling, and mechanical properties of these films were investigated. The antibacterial property was enhanced by incorporating Hypericum perforatum L. and Citrus More >

Ruirui Zhang¹, Xuguang Zhang², Minxin Yang³, Haoran Zhang^4,5,*

International Journal of Mental Health Promotion, Vol.26, No.2, pp. 117-126, 2024, DOI:10.32604/ijmhp.2023.045819

Abstract Contingent self-esteem captures the fragile nature of self-esteem and is often regarded as suboptimal to psychological functioning. Self-compassion is another important self-related concept assumed to promote mental health and well-being. However, research on the relation of self-compassion to contingent self-esteem is lacking. Two studies were conducted to explore the role of self-compassion, either as a personal characteristic or an induced mindset, in influencing the effects of contingent self-esteem on well-being. Study 1 recruited 256 Chinese college students (30.4% male, mean age = 21.72 years) who filled out measures of contingent self-esteem, self-compassion, and well-being. The… More >

Shulan Lei^1,2, Shujuan Wang¹, Zhuohong Zhu^1,2, Min Lu^1,2, Xinying Li^1,2, Yiming Shen³, Jing Chen^1,2,*

International Journal of Mental Health Promotion, Vol.26, No.1, pp. 61-67, 2024, DOI:10.32604/ijmhp.2023.045478

Abstract The purpose of this study was to explore the reliability and validity of the Warwick-Edinburgh Mental Well-being Scale (WEMWBS) among Chinese civil servants, thus establishing a useful tool for assessing the mental health of individuals in this occupation. The WEMWBS, Satisfaction with Life Scale (SWLS), and Depression Anxiety and Stress Scale-21 (DASS-21) were administered to a sample of 2,624 civil servants (42.860 ± 9.690 years) in a city located within Shandong Province, China. The findings revealed significant differences between groups with high and low scores on each item of the WEMWBS (t = 48.127–78.308, all p… More >