Miguel Ángel Ramírez¹, Luis Alfonso^†, Patricia González², Juan Reinerio Fagundo², Margaret Suarez³, Clara Melian³, Tania Rodríguez¹, Carlos Peniche^4,*

Journal of Renewable Materials, Vol.3, No.1, pp. 73-80, 2015, DOI:10.7569/JRM.2014.634116

Abstract The demineralization kinetics of deproteinized lobster shells using CO₂ were studied. Demineralization reaction proceeds until the concentration of Ca⁺² in solution reaches an equilibrium value. The introduction of a cation exchange resin (cationite), in an open system for CO₂ , allows replacement of the solution Ca²⁺ ions by Na⁺ ions, whereby the equilibrium shifts and an effective dissolution of the exoskeletons’ calcite is achieved. The mathematical relationships between the conductivity of the solution and the concentrations of major ions, the rate constants and kinetic parameters of the reaction in the absence and presence of the resin were obtained. It was… More >

Shunjie Liu^1,2, Yusheng Qin^1,*, Xianhong Wang^1,*, Fosong Wang¹

Journal of Renewable Materials, Vol.3, No.2, pp. 101-112, 2015, DOI:10.7569/JRM.2014.634140

Abstract Precursors with sharp crystalline transition temperature have attracted signifi cant attention in the fi eld of shape-memory materials; however, seldom have reports been related to amorphous ones with industrial application prospects. This study introduced a new family of amorphous CO₂ -based hydroxyl-telechelic three-armed oligo(carbonate-ether) triol (Triol) with controllable molecular weight (M_n) and carbonate unit content (CU), which was coupled with PEG and 1,6-hexamethylene diisocyanate (HDI) to afford crosslinked polyurethanes (PU) networks with well-defi ned architecture. A crosslinking point was provided by Triol and PEG was used to afford networks some crystallinity. The resulting networks were characterized using attentuated total refl… More >

Guanwen Ding, Qifen Li^*, Liting Zhang, Yuanbo Hou, Xiaoxiao Yan

Journal of Renewable Materials, Vol.11, No.1, pp. 197-207, 2023, DOI:10.32604/jrm.2023.020277

Abstract Realization of CO₂ resource utilization is the main development direction of CO₂ reduction. The CO₂ methanation technology based on microbial electrolysis cell (MEC) has the characteristics of ambient temperature and pressure, green and low-carbon, which meets the need of low-carbon energy transition. However, the lack of the system such as the change of applied voltage and the reactor amplification will affect the methane production efficiency. In this research, the efficiency of methane production with different applied voltages and different types of reactors was carried out. The results were concluded that the maximum methane production rate of the H-type two-chamber microbial… More >

Adela POP (Puscasiu), Alexandra Fanca^*, Dan Ioan Gota, Honoriu Valean

Intelligent Automation & Soft Computing, Vol.35, No.1, pp. 925-940, 2023, DOI:10.32604/iasc.2023.025069

Abstract The amount of moisture in the air is represented by relative humidity (RH); an ideal level of humidity in the interior environment is between 40% and 60% at temperatures between 18° and 20° Celsius. When the RH falls below this level, the environment becomes dry, which can cause skin dryness, irritation, and discomfort at low temperatures. When the humidity level rises above 60%, a wet atmosphere develops, which encourages the growth of mold and mites. Asthma and allergy symptoms may occur as a result. Human health is harmed by excessive humidity or a lack thereof. Dehumidifiers can be used to… More >

Jinguang Yang, Feng Zhao, Min Zhang^*, Yan Liu, Xiaofang Wang

CMES-Computer Modeling in Engineering & Sciences, Vol.126, No.3, pp. 935-953, 2021, DOI:10.32604/cmes.2021.014176

Abstract For a radial inflow turbine (RIT), leakage flow in impeller backface cavity has critical impacts on aerodynamic performance of the RIT and axial force acting on the RIT impeller. In order to control this leakage flow, different types of labyrinth seals are numerically studied in this paper based on a supercritical carbon dioxide (S-CO₂) RIT. The effects of seal clearance and cavity outlet pressure are first analyzed, and the impacts of seal design parameters, including height, number and shape of seal teeth, are evaluated. Results indicate that adding labyrinth seal can improve cavity pressure and hence adequately inhibits leakage flow.… More >

Yujie Bai^1,*, Youquan Huang³, Guangsheng Cao¹, Xiaohan Nan¹, Qingchao Cheng¹, Lei Wang², Tong Du⁴

Journal of Renewable Materials, Vol.9, No.4, pp. 651-669, 2021, DOI:10.32604/jrm.2021.014479

Abstract This study analyzed the partial effect of carbon dioxide hydrate in reaction kettle experiments. The particle and bubble characteristics of the crystal nucleus during carbon dioxide hydrate decomposition were observed under the microscope. The results showed that in the temperature range of 0.5°C–3.5°C, the pressure range of 3 MPa– 5.5 MPa, phase characteristics in the reaction kettle changed in a complex fashion during carbon dioxide hydrate formation. During hydrate decomposition, numerous carbon dioxide bubbles were produced, mainly by precipitation at high temperatures or in the hydrate cage structure. The hydrate crystal nucleus initially exhibited fluidity in the reaction. However, as… More >

Amin Bemani¹, Alireza Baghban², Shahaboddin Shamshirband^{3, 4, *}, Amir Mosavi^{5, 6, 7}, Peter Csiba⁷, Annamaria R. Varkonyi-Koczy^{5, 7}

CMC-Computers, Materials & Continua, Vol.63, No.3, pp. 1175-1204, 2020, DOI:10.32604/cmc.2020.07723

Abstract In the present work, a novel machine learning computational investigation is carried out to accurately predict the solubility of different acids in supercritical carbon dioxide. Four different machine learning algorithms of radial basis function, multi-layer perceptron (MLP), artificial neural networks (ANN), least squares support vector machine (LSSVM) and adaptive neuro-fuzzy inference system (ANFIS) are used to model the solubility of different acids in carbon dioxide based on the temperature, pressure, hydrogen number, carbon number, molecular weight, and the dissociation constant of acid. To evaluate the proposed models, different graphical and statistical analyses, along with novel sensitivity analysis, are carried out.… More >

Xiaofeng Yang^{1, *}, Yanhong Li¹, Aiguo Nie¹, Sheng Zhi², Liyuan Liu³

CMES-Computer Modeling in Engineering & Sciences, Vol.122, No.3, pp. 1141-1157, 2020, DOI:10.32604/cmes.2020.08538

Abstract Supercritical carbon dioxide (Sc-CO₂) jet rock breaking is a nonlinear impact dynamics problem involving many factors. Considering the complexity of the physical properties of the Sc-CO₂ jet and the mesh distortion problem in dealing with large deformation problems using the finite element method, the smoothed particle hydrodynamics (SPH) method is used to simulate and analyze the rock breaking process by Sc-CO₂ jet based on the derivation of the jet velocity-density evolution mathematical model. The results indicate that there exisits an optimal rock breaking temperature by Sc-CO₂. The volume and length of the rock fracture increase with the rising of the… More >

Yinghui Sun¹, Guojie Zhang^1,2,*

The International Conference on Computational & Experimental Engineering and Sciences, Vol.22, No.1, pp. 105-105, 2019, DOI:10.32604/icces.2019.05173

Abstract A series of Co-M (M = Ce, Fe, Zr) binary oxides supported on N-doped catalysts were prepared by impregnation methods and tested for DRM reaction. Moreover, the influence of Co and Ce atomic contents in the catalysts on DRM performance was investigated. Significant enhancement of activity performance over Ce promoted 3Co-1Ce/AC-N catalyst was observed. Compared with Fe and Zr, the catalyst with 1/4 mol% of Ce showed the highest activity and was higher than the supported Co catalyst. The calcined and spent catalysts were characterized by XPS, H₂-TPR, TEM and EDX mapping studies. The characterization results demonstrated that the improved… More >

N. A. Sri Aprilia¹, M. S. Nurul Atiqah², Zhari Ismail³, C. Y. Loo², Chaturbhuj K. Saurabh², Rudi Dungani⁴, Abdul Khalil H.P.S^2*

Journal of Renewable Materials, Vol.5, No.5, pp. 380-387, 2017, DOI:10.7569/JRM.2017.634130

Abstract Due to environmental concerns, green composites have become a highly researched material. In the present study, kenaf fiber was used as reinforcement in epoxy-based composite with weight fraction ranges from 0, 5, 10, and 15% (w/w of resin). The ratio of epoxy to hardener was 65:32.5. Prior to incorporation, kenaf bast fiber underwent Soda-AQ pulping followed by total chlorine-free bleaching (OAZP sequence). The obtained pulp was then subjected to supercritical carbon dioxide extraction (SCE) treatment. It was observed that epoxy composite with 10% of fiber loading demonstrated the highest mechanical properties with a tensile strength of 64 MPa, tensile modulus… More >