Cracking furnace system is the starting and the most critical sector of an ethylene plant where heavier components are cracked into lighter products, such as ethylene, propylene, and etc. During the production, coking can adversely affect the manufacturing performance, such that furnaces have to be decoked for some controlled time. The cracking and decoking processes both influence the plant pr...

Article history: Received: 08.10.2013. Received in revised form: 21.11.2013. Accepted: 25.11.2013. This study presents a cellular automata (CA) method to map the cracking patterns of laterally loaded masonry wall panels with openings. Firstly, the central point displacement of each CA cell is calculated from the finite element method (FEM). Then, the displacements are normalized to form the CA ...

Abstract:This paper addresses the short-term scheduling problem for the ethylene cracking process with feedstocks and energy constraints. The cracking production of ethylene is a process with units that have decaying performance, requiring periodic cleanup to restore their performance. Under the condition of limited feedstocks, the production operating mode of the cracking furnaces is to keep y...

At the age of 3.5 years, wild chimpanzees at Bossou, Guinea, begin to use hammer and anvil stones to crack oil-palm nuts to get the kernels. To clarify the developmental processes, the authors did a field experiment in which stones and oil-palm nuts were provided. Infant chimpanzees' stone-nut manipulation was observed and video recorded. Data were collected from 3 infants younger than 4 years ...

Article history: Received: 11.03.2013. Received in revised form: 02.04.2013. Accepted: 02.04.2013. This paper puts forward an innovative criterion in the cellar automata (CA) technique for both matching zone similarity and mapping failure pattern of masonry wall panel. The criterion proposed in this paper is a two-step matching method. Firstly, calculate the state values of the cells in the bas...

Existing design guidelines for concrete hinges consider bending-induced tensile cracking, but the structural behavior is oversimplified to be time-independent. This is the motivation to study creep and bending-induced tensile cracking of initially monolithic concrete hinges systematically. Material tests on plain concrete specimens and structural tests on marginally reinforced concrete hinges a...

Cross-linked protein crystals (CLPCs) are very useful materials in applications such as biosensors, catalysis, and X-ray crystallography. Hence, preparation of CLPCs is an important research direction. During the preparation of CLPCs, an often encountered problem is that cracks may appear in the crystals, which may finally lead to shattering of the crystals into small pieces and cause problem i...

Researchers are currently developing new value-added uses for almond shells, an abundant agricultural by-product. Almond varieties are distinguished by processors as being either hard or soft shelled, but these two broad classes of almond also exhibit varietal diversity in shell morphology and physical characters. By defining more precisely the physical and chemical characteristics of almond sh...