Junjie Zhao, Diyuan Li^*, Jingtai Jiang, Pingkuang Luo

CMES-Computer Modeling in Engineering & Sciences, Vol.140, No.1, pp. 275-304, 2024, DOI:10.32604/cmes.2024.046960

Abstract Traditional laboratory tests for measuring rock uniaxial compressive strength (UCS) are tedious and time-consuming. There is a pressing need for more effective methods to determine rock UCS, especially in deep mining environments under high in-situ stress. Thus, this study aims to develop an advanced model for predicting the UCS of rock material in deep mining environments by combining three boosting-based machine learning methods with four optimization algorithms. For this purpose, the Lead-Zinc mine in Southwest China is considered as the case study. Rock density, P-wave velocity, and point load strength index are used as input variables, and UCS is regarded… More > Graphic Abstract

Susi Susi^1,2,*, Makhmudun Ainuri^3,*, Wagiman Wagiman³, Mohammad Affan Fajar Falah³

Journal of Renewable Materials, Vol.12, No.3, pp. 513-537, 2024, DOI:10.32604/jrm.2024.045586

Abstract Microcrystalline cellulose (MCC) is one of the cellulose derivatives produced as a result of the depolymerization of a part of cellulose to achieve high crystallinity. When implemented in other polymers, high crystallinity correlates with greater strength and stiffnes, but it can reduce the water-holding capacity. The acid concentration and hydrolysis time will affect the acquisition of crystallinity and water absorption capacity, both of which have significance as properties of hydrogel filler. The study aimed to evaluate the properties and select the MCC generated from varying the proportion of hydrochloric acid (HCl) and the appropriate hydrolysis time as a filler for… More > Graphic Abstract

R. VENKATESAN^*, S. R. DARSON IMMANUEL JOHN, N. RAJESWARI

Journal of Polymer Materials, Vol.36, No.3, pp. 261-273, 2019, DOI:10.32381/JPM.2019.36.03.6

Abstract Nanocomposite films of chitosan (CH) incorporated with different wt. % of the polyoligomericsilsesquioxane (POSS) were prepared by solution casting. The thermal, mechanical, morphological and antimicrobial properties of the nanocomposites were examined. TGA analyses of the nanocomposites indicate that the filler enables the enhancement of thermal stability of chitosan. The tensile strength of the nanocomposite films is enhanced (10.9 MPa for neat chitosan to 24.0MPa for 5wt. % filled chitosan) by the addition of POSS while the elongation at break is reduced. The nanocomposite films exhibited excellent antimicrobial activity against both gram positive and gram negative bacteria. This activity increases with… More >

SHOGO TAKASUKA^1,*, TATSUHIRO TAKAHASHI¹

Journal of Polymer Materials, Vol.38, No.1-2, pp. 1-10, 2021, DOI:10.32381/JPM.2021.38.1-2.1

Abstract The effects of compounds containing oxazoline groups and the presence of maleic anhydridegrafted polypropylene (PP-g-MAH) on the spectral, morphological, and tensile properties of polypropylene (PP)/liquid crystalline polymer (LCP) blends were investigated. A wholly aromatic LCP having a low melting point which was copolyester, namely AL-7000 have been used, because thermal decomposition of PP and compatibilizer must be prevented.Compression molding was selected as the molding method because it allows molding with a small amount of sample. The binary blends of PP and LCP showed a degradation of tensile properties compared to pure PP. However, the addition of 2,2'-bis(2-oxazoline) and PP-g-MAH as… 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 limon L. oils in the… More >

MUHAMAD SOFFI BIN MANDA^1,2, MOHD RUZAIMI BIN MAT REJAB¹, SHUKUR ABU HASSAN^3,4, MAT UZIR BIN WAHIT^3,4, JOSEPH SELVI BINOJ^5,*, BRIGHT BRAILSON MANSINGH⁶, SITI SAFARAH BINTI AMIRNUDDIN³, ALAMRY ALI⁷, KHENG LIM GOH^8,9, DIDIK NURHADIYANTO¹⁰

Journal of Polymer Materials, Vol.39, No.3-4, pp. 241-253, 2022, DOI:10.32381/JPM.2022.39.3-4.5

Abstract This study investigates the potential of Tin Slag Polymer Concrete (TSPC) strengthening through confinement using basalt fiber reinforced polymer (BFRP) and aramid fiber reinforced polymer (AFRP) confinement. TSPC short cylindrical column samples have been wrapped with BFRP and AFRP in a single layer (30 mm overlap) using Sikadur-330 epoxy and final samples were coded as TSPC-UC, TSPC-BF and TSPC-AF for unconfined, BFRP and AFRP for confined respectively. After curing for 30 days at room temperature, compressive test has been performed to know the strength, modulus, strain, fracture energy and failure modes of unconfined and confined TSPC. Test result shows that… More >

XINGMIN XU¹, QINGQING SUN², AIRONG XU², XINBAO GUO²

Journal of Polymer Materials, Vol.39, No.1-2, pp. 167-181, 2022, DOI:10.32381/JPM.2022.39.1-2.11

Abstract Silk fibroin (SF) with renewability, biocompatibility and biodegradability shows potential application in various fields including biomedicine, tissue engineering, and wearable electronic devices. Herein, SF is used to exert effective reinforcement of polyvinyl alcohol (PVA) composite film to further improve its practicability. As such, PVA/SF composite films were prepared for the first time using a facile approach. The films were characterized to investigate possible interaction of PVA with SF. Meanwhile, systematic investigations have also been completed to explore the influences of PVA/SF mass ratio on the mechanical properties (tensile strength, elongation at break), biodegradability and biocompatibility, the morphology, crystallinity, chemical structure… More >

Ran Wang¹, Aimin Gong^1,*, Shanqing Shao¹, Baoli Qu², Jing Xu³, Fulai Wang¹, Feipeng Liu^3,*

FDMP-Fluid Dynamics & Materials Processing, Vol.20, No.4, pp. 749-769, 2024, DOI:10.32604/fdmp.2023.042566

Abstract The mechanical properties of cementitious sand and gravel damming material have been experimentally determined by means of microscopic SEM (Scanning Electron Microscopy) image analysis. The results show that the combination of fly ash and water can fill the voids in cemented sand and gravel test blocks because of the presence of hydrated calcium silicate and other substances; thereby, the compactness and mechanical properties of these materials can be greatly improved. For every 10 kg/m³ increase in the amount of cementitious material, the density increases by about 2%, and the water content decreases by 0.2%. The amount of cementitious material used… More > Graphic Abstract

Wei Chen^*, Wuwen Liu, Yue Liang

FDMP-Fluid Dynamics & Materials Processing, Vol.20, No.4, pp. 859-872, 2024, DOI:10.32604/fdmp.2023.029310

Abstract River sand is an essential component used as a fine aggregate in mortar and concrete. Due to unrestrained exploitation, river sand resources are gradually being exhausted. This requires alternative solutions. This study deals with the properties of cement mortar containing different levels of manufactured sand (MS) based on quartzite, used to replace river sand. The river sand was replaced at 20%, 40%, 60% and 80% with MS (by weight or volume). The mechanical properties, transfer properties, and microstructure were examined and compared to a control group to study the impact of the replacement level. The results indicate that the compressive… More >

Bayi Xu¹, Lei Sun^2,*, Xiuqing Mao², Chengwei Liu³, Zhiyi Ding²

CMC-Computers, Materials & Continua, Vol.78, No.2, pp. 1995-2022, 2024, DOI:10.32604/cmc.2023.046478

Abstract In recent years, frequent network attacks have highlighted the importance of efficient detection methods for ensuring cyberspace security. This paper presents a novel intrusion detection system consisting of a data preprocessing stage and a deep learning model for accurately identifying network attacks. We have proposed four deep neural network models, which are constructed using architectures such as Convolutional Neural Networks (CNN), Bi-directional Long Short-Term Memory (BiLSTM), Bidirectional Gate Recurrent Unit (BiGRU), and Attention mechanism. These models have been evaluated for their detection performance on the NSL-KDD dataset.To enhance the compatibility between the data and the models, we apply various preprocessing… More >