Nikola Stosic^**, Ian K. Smith, Ahmed Kovacevic

Frontiers in Heat and Mass Transfer, Vol.3, No.2, pp. 1-7, 2012, DOI:10.5098/hmt.v3.2.3003

Abstract Due to fast rotation of screw compressor rotors, temperature is uniform in the rotor cross section and temperature field is a function of the axial coordinate only. Apart of that the rotors in one cross section the rotors are simultaneously heated by hot gas on one side while cooled at another side by cold gas. As a result of identification of the main modes of heat transfer both in the rotors and between the rotors and their surroundings and the relative significance of each, a novel procedure is suggested to cool the rotors by injection of minute quantities of a… More >

Samsudin Anis^1,*, Deni Fajar Fitriyana¹, Aldias Bahatmaka¹, Muhammad Choirul Anwar¹, Arsyad Zanadin Ramadhan¹, Fajar Chairul Anam¹, Raffanel Adi Permana¹, Ahmad Jazilussurur Hakim², Natalino Fonseca Da Silva Guterres³, Mateus De Sousa Da Silva³

Journal of Renewable Materials, Vol.12, No.2, pp. 381-396, 2024, DOI:10.32604/jrm.2023.047128

Abstract Indonesia is one of the largest coconut-producing countries in the world. The utilization of coconut shell waste into briquettes will increase the selling value and become a great export opportunity. However, the effect of adhesives on the quality of coconut shell charcoal briquettes made using screw extruder machine has not been widely studied. This study aims to determine the effect of adhesive type on the quality of coconut shell charcoal briquettes. The process of fabricating briquettes in this study included crushing, mixing, blending, pressing, and drying. In the mixing process, 3 types of adhesives were used, namely tapioca flour (Briquette_1),… More > Graphic Abstract

Huifeng Yang, Mingwang Wu, Rixin Gu, Hang Cao, Kai Xiao, Benkai Shi^*

Journal of Renewable Materials, Vol.11, No.12, pp. 4175-4195, 2023, DOI:10.32604/jrm.2023.028507

Abstract This article presents experimental results of steel-timber-steel (STS) joints loaded parallel to grain. Eight groups of specimens were designed, and tensile tests were performed. The fastener types and fastener numbers were considered to evaluate the tensile strengths and ductility performances of the STS joints. The screws with 6 mm diameter and the innovative steel-tubes with 18 mm diameter were adopted as connecting fasteners. The experimental results were discussed in terms of yielding and ultimate strengths, slip stiffness, and ductility factors. The ductility classification and failure mechanisms of each group of specimens were analyzed. It was demonstrated that the STS joint… More >

De Li^1,#, Bengang Zhang^1,#, Yuan Tu¹, Guoming Xiao¹, Meifen Tian², Xiaoxue Xu¹, Xiao Zhong¹, Qiaoyan Zhang³, Zhigang Wu^1,*, Jiankun Liang^4,*

Journal of Renewable Materials, Vol.11, No.10, pp. 3725-3738, 2023, DOI:10.32604/jrm.2023.027895

Abstract Screw connection is a type most commonly applied to timber structures. As important commercial tree species in China, Masson pine and Chinese fir have the potential to prepare wood structures. In this study, the effects of the diameter of the self-tapping screw and the guiding bores on the nail holding performance on different sections of Masson pine and Chinese fir dimension lumbers were mainly explored. The results showed that: (1) The nail holding strength of the tangential section was the maximum, followed by that of the radial section, and that of the cross section was the minimum. (2) The nail… More >

Muhammad Ghozali^1,2, Yenny Meliana², Widya Fatriasari³, Petar Antov⁴, Mochamad Chalid^1,*

Journal of Renewable Materials, Vol.11, No.4, pp. 1963-1976, 2023, DOI:10.32604/jrm.2023.026060

Abstract Sugar palm (Arenga pinnata) starch is considered an important renewable, biodegradable, and eco-friendly polymer, which is derived from agricultural by-products and residues, with great potential for the development of biocomposite materials. This research was aimed at investigating the development of TPS biocomposites from A. pinnata palm starch using an extrusion process. Palm starch, glycerol, and stearic acid were extruded in a twin-screw extruder. Scanning electron microscopy (SEM) analysis of TPS showed that the starch granules were damaged and gelatinized in the extrusion process. The density of TPS was 1.3695 g/mL, lower than that of palm starch, and the addition of… More > Graphic Abstract

Qingguo Ben¹, Congcong Zhang², Benkai Shi², Huifeng Yang^2,*

Journal of Renewable Materials, Vol.10, No.12, pp. 3599-3610, 2022, DOI:10.32604/jrm.2022.022344

Abstract Stress laminated timber (SLT) deck is assembled using timber (lumber or glulam) components placed side by side and stressed together, which has the advantages of easy prefabrication and good cost performance. This work presented an experimental investigation of bending tests performed on SLT slabs. Several parameters, including prestress levels, distance of pre-stressing bars, and the existence of self-tapping screw (STS) reinforcement, were taken into consideration. To reinforce the compressive property of timber perpendicular to the grain, the STSs were placed under the anchor plate of the pre-stressed bars. The experimental results were analyzed and discussed in terms of failure modes,… More > Graphic Abstract

Xudong Zhu^1,2,3, Yingying Xue², Xuewen Zhang², Pengfei Qi², Jie Shen², Changtong Mei^1,*

Journal of Renewable Materials, Vol.10, No.2, pp. 401-413, 2022, DOI:10.32604/jrm.2022.016464

Abstract A new beech and self-tapping screw composite dowel is proposed and studied, its performance being compared with that of beech dowels and self-tapping screws alone. The single shear performance of components connected by composite dowels was tested. Results show that the dowels are a good choice for components requiring high stiffness. Screws remain a good choice for components requiring excellent seismic performance. Combination group presents similar maximum load stiffness to those of composite dowels, but other ductility parameters are superior for composite dowels. The best connection mode was provided by two composite dowels. Based on connecting two points, structural elements… More >

Zhentao Chen¹, Weidong Lu^1,2,*, Yingwei Bao¹, Jun Zhang¹, Lu Wang¹, Kong Yue¹

Journal of Renewable Materials, Vol.10, No.1, pp. 89-104, 2022, DOI:10.32604/jrm.2021.015925

Abstract The timber-concrete composite (TCC) slabs have become a preferred choice of floor systems in modern multi story timber buildings. This TCC slab consisted of timber and a concrete slab which were commonly connected together with inclined self-tapping screws (STSs). To more accurately predict the fire performance of TCC slabs, the mechanical behavior of TCC connections under high temperature was investigated by numerical simulation in this study. The interface slip of TCC connections was simulated by a proposed Finite Element (FE) model at room temperature, and different diameter and penetration length screws were considered. The effectiveness of this FE model was… More > Graphic Abstract

Huifeng Yang^1,*, Junfeng Ji¹, Haotian Tao², Benkai Shi¹, Junbin Hu¹, Bo Wen³

Journal of Renewable Materials, Vol.10, No.1, pp. 105-117, 2022, DOI:10.32604/jrm.2021.016118

Abstract Experimental investigation on the pull-out behaviour, including the withdrawal capacity, slip stiffness and interfacial shear stress, of axially loaded screwed-in threaded rod embedded in cross laminated timber (CLT) was conducted. Specimens with varying embedment length and different number of threaded rods were tested in this study. To prevent premature splitting failure of timber, some specimens were reinforced in the direction perpendicular to the timber grain with self-tapping screws. Test results showed that the screwed-in threaded rod connections exhibited good pull-out behaviour with high withdrawal capacity and slip stiffness. Within a certain range, the withdrawal capacity increases considerably with the increase… More > Graphic Abstract

Matea Perić^1,*, Robert Putz¹, Christian Paulik²

Journal of Renewable Materials, Vol.8, No.7, pp. 759-772, 2020, DOI:10.32604/jrm.2020.09284

Abstract In the current study poly(lactic acid) PLA composites with a 3 wt% and 5 wt% of nanofibrillated cellulose (NFC) were produced by 3D-printing method. An enzymatic pretreatment coupled with mechanical fibrillation in a twin screw extruder was used to produce high consistency NFC. Scanning electron microscopy (SEM) equipped with Fibermetric software, FASEP fiber length distribution analysis, Furrier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), tensile tests, impact tests and differential scanning calorimetry were used to characterize NFC and PLA/NFC composites. The results of the fiber length and width measurements together with the results of the SEM analysis showed that enzymatic… More >