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DEM Modelling of Particle Movement During Seepage Failure
Issue:
Volume 9, Issue 3, June 2021
Pages:
62-67
Received:
4 February 2021
Accepted:
15 February 2021
Published:
14 May 2021
Abstract: The Discrete Element Method (DEM) is a calculation method by which a particle flow at a single particle occurs. It is widely used in many fields such as coastal engineering, mining and civil engineering. Specifically, when small particles are taken away by water, pores will increase and collapse due to the soil's own weight, which will cause other parts of the soil to deform. Due to the continuous development of piping, small soil particles are taken away from the entrance, so the entrance is constantly expanding. Once the upper layer of soil loses the support below, the upper layer of particles will collapse under infiltration. Therefore, as the above phenomenon continues to develop, the amount and flow of water will increase. At the same time, this will increase the rate of seepage destruction. In fact, the law of particle motion includes the growth, aggregation, diffusion and crystallization of particles under different conditions, which can be applied to other fields, such as the research of material surface roughness in textile science, the crystal origin and potential self-rotation in electronic engineering, etc. The research of this paper can provide a further theoretical basis and framework for the above direction, and pave the way for the majority of scholars to carry out the follow-up research work. In this article, EDEM (Electronic Discrete Element Method) modeling is used to simulate the movement of particles during the slip.
Abstract: The Discrete Element Method (DEM) is a calculation method by which a particle flow at a single particle occurs. It is widely used in many fields such as coastal engineering, mining and civil engineering. Specifically, when small particles are taken away by water, pores will increase and collapse due to the soil's own weight, which will cause other ...
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A Novel Synthesis Technology of Ethyl-β-Cyclodextrin
Gan Yongjiang,
Zhang Bei,
Zhang Yimin,
Ling Shanfeng
Issue:
Volume 9, Issue 3, June 2021
Pages:
68-71
Received:
18 April 2021
Accepted:
5 May 2021
Published:
20 May 2021
Abstract: A novel green synthesis process about ethyl-β-Cyclodextrin have been investigated through the reaction between β-cyclodextrin and diethyl carbonate by used anhydrous potassium carbonate as catalyst in DMF. The influence of experimental factors including reaction time, the molar ratio of β-cyclodextrin to diethyl carbonate, reaction temperature and contents of anhydrous potassium carbonate on the average degree of substitution of ethyl-β-cyclodextrin were carried out by a design method of orthogonal experiments. The results shown that the average degree of substitution of ethyl-β-cyclodextrin can be depend on the reaction temperature and the molar ratio of raw material primarily. The optimal maximum average degree of substitution of ethyl-β-cyclodextrin is 6.0 when the molar ratio of β-cyclodextrin to diethyl carbonate, reaction temperature, reaction time and dosage of catalyst are 1:28, 120°C, 24h and 2.0 g, respectively. The structures of ethyl-β-cyclodextrin were characterized by TLC, IR, MS, 1H-NMR and 13C-NMR, and these results are concordant with former ones which synthesized ethyl-β-cyclodextrin by diethyl sulfate or ethyl iodide.
Abstract: A novel green synthesis process about ethyl-β-Cyclodextrin have been investigated through the reaction between β-cyclodextrin and diethyl carbonate by used anhydrous potassium carbonate as catalyst in DMF. The influence of experimental factors including reaction time, the molar ratio of β-cyclodextrin to diethyl carbonate, reaction temperature and ...
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Immobilized Thiosalicylic Ligand System Potentials for the Detoxification of Some Heavy Metals from Tannery Wastewater
Bulus Habila,
Emmanuel Chidiebere Ezeh,
Simon Moses Saidu,
John Chidozie Attah,
Paul Okechukwu Nsude,
Emmanuel Agboeze,
Ike Christian Ozoemena,
Jonathan Danladi Gaiya,
Tachye Ninnat Bwankhot Shekarri,
Sunday Ture Dahiru,
Olajide Joseph Igbehinadun
Issue:
Volume 9, Issue 3, June 2021
Pages:
72-79
Received:
20 April 2021
Accepted:
20 May 2021
Published:
29 June 2021
Abstract: Polysiloxanes are characterized by silicon and oxygen backbone and are hydrophobic in nature with low moisture uptake widely used for medical applications. Polysiloxane immobilized thiosalicylic acid ligand system has been prepared through sol-gel method, gelation was observed after 40 minutes. The immobilized ligand was characterized using FTIR, the spectrum showed characteristic absorption bands (cm-1) at: 3377 (OH), 2981 (C-H stretch); 2631 (SH); 1587 to 1684 (C=C, C=O); 1032 to 1144 (Si - O) respectively. SEM analysis showed irregular particle sizes of the polysiloxane matrices while EDX elemental composition gave (wt %): 3-CPPS; Si (50.45), O (25.02) and Cl (24.57). F - 3CPPS showed, O (58.68), Si (41.32); thiosalicylic (7.14 of S). The extraction of metal ions (Cr3+, Fe3+, Pb2+, Cu2+ and Zn2+) were studied using Microwave Plasma Atomic Emission Spectrophotometer (Agilent MPAES-4200) at pH 6.0. Thermodynamic range with respect to Cr3+, Fe3+, Pb2+, Cu2+ and Zn2+ yielded negative values forΔGo: Cu2+-(11.483 to 14.842) to Zn2+ -(14.368 to 14.842)KJmol-1; positive values for ΔHo: Fe3+ (0.000) to Pb2+ (105.130)KJmol-1 and ΔSo: Zn2+ (47.421) to Pb2+ (389.328)Jmol1K1 respectively, indicating spontaneous, endothermic reactions and high degree of disorderliness with respect to metal ion binding capacity to the ligand system.
Abstract: Polysiloxanes are characterized by silicon and oxygen backbone and are hydrophobic in nature with low moisture uptake widely used for medical applications. Polysiloxane immobilized thiosalicylic acid ligand system has been prepared through sol-gel method, gelation was observed after 40 minutes. The immobilized ligand was characterized using FTIR, t...
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