Study of FSRU-LNGC System Based on a Quantitative Multi-cluster Risk Informed Model

PresentationThe offshore LNG terminal, referred to as LNG floating storage unit or floating storage and re- gasification unit (FSRU), performs well on both building process and operation process. The LNG FSRU is a cost-effective and time efficient solution for LNG transferring in the offshore area, and it brings minimal impacts to the surrounding environment as well. This paper proposed a systematic method to integrate chemical process safety with maritime safety analysis. The evaluation network was adopted to process a comparison study between two possible locations for LNG offshore FSRU. This research divided the whole process into three parts, beginning with the LNG Carrier navigating in the inbound channel, the berthing operation and ending with the completion of LNG transferring operation. The preferred location is determined by simultaneously evaluating navigation safety, berthing safety and LNG transferring safety objectives based on the quantitative multi-cluster network multi-attribute decision analysis (QMNMDA) method. The maritime safety analysis, including navigational process and berthing process, was simulated by LNG ship simulator and analyzed by statistical tools; evaluation scale for maritime safety analysis were determined by analyzing data from ninety experts. The chemical process safety simulation was employed to LNG transferring events such as connection hose rupture, flange failure by the consequence simulation tool. Two scenarios, i.e., worst case scenario and maximum credible scenario, were taken into consideration by inputting different data of evaluating parameters. The QMNMDA method transformed the evaluation criteria to one comparable unit, safety utility value, to evaluate the different alternatives. Based on the final value of the simulation, the preferred location can be determined, and the mitigation measures were presented accordingly

Optimize Ventilation Systems in Confined Workplaces Using Computational Fluid Dynamics

Chemical industry and society always want to eliminate the damage to the environment and lower the casualty if an incident occurs. Finding a more efficient and effective way to achieve this goal is now more critical than ever. The ventilation system is the most common engineering method to control the airborne toxic and explosive material in confined workplaces. The purpose of ventilation is to dilute or remove the toxic and explosive vapors with air to prevent potential poisoning or explosion. Optimized ventilation system design is critical to industrial hygiene control and to improve ventilation system efficiency. Insufficient ventilation can directly threaten the worker’s health and life. A properly designed industrial ventilation system can significantly improve the safety of workplaces and maintain a comfortable work condition. Ventilation can also prevent the corrosion and increase the life of process units and equipment. Newly designed chemical facilities should make sure that proper ventilation systems are used to control air quality, and plants already in operation should also carefully evaluate the work environment to ensure compliance with the federal codes and regulations. Computational Fluid Dynamics has been used in this thesis to analyze the fluid dynamics performance in the laboratory environment using the dilution ventilation system. A variety of different ventilation system installation schemes are proposed, and the performance of different schemes is examined and compared through simulation to get the optimal installation plan for the best contaminant control. The proposed scheme also optimizes the ventilating system installation by investigating the system’s performance with different transmitted mediums. The results of this work can serve as references to maximize the ventilation efficiency and minimize the energy cost

Development of Machine Learning Based Prediction Models For Safety Related Properties and Consequences

Safety-related properties like lower flammable limit (LFL), upper flammable limit (UFL), auto-ignition temperature (AIT) and flash point (FP) are crucial hazardous properties for fire and explosion hazards assessment and consequence analysis. There is a significant amount of study trying to accurately predict these properties, however, the well-developed quantitative structure-property relationship (QSPR) analysis still has limited applications due to its limited mixture property database and ambiguous descriptor selection mechanism. This study aims to construct an expanded chemical mixture database of chemical mixture hazardous properties. Machine learning-based algorithms are implemented in the quantitative structure-property relationship (QSPR) analysis to improve the descriptor selection process and model performance. Besides, the incidental release of flammable/toxic gases and liquids can lead to the formation of flammable/toxic vapor clouds. Fires and explosions caused by the flammable cloud with the presence of an ignition source and severe toxication can also happen with the presence of the toxic cloud. Which can be highly hazardous to chemical plants as well as the surrounding communities. This study also trying bridge the gap between the micro-focused QSPR study and macro-focused consequence prediction models to develop highly efficient quantitative property-consequence relationship (QPCR) models based on developed QSPR models to accurately predict the downwind maximum distance, minimum distance, and maximum vapor cloud width within certain concentration limit or lethality, which can be used to obtain instant flammable dispersion estimations for various flammable chemicals at much lower computational costs

Evaluation of inhibitory effects of geniposide on a tumor model of human breast cancer based on 3D printed Cs/Gel hybrid scaffold

Traditional Chinese medicine therapy, which can serve as adjuvant therapy for cancer treatment, has no obvious side effects on the human body. Geniposide (GEN), one of the main iridoid glycosides in gardenia fruit, has been widely reported to have anti-cancer effects. In this study, we aimed to inspect whether GEN could inhibit proliferation and promote the apoptosis of human breast cancer cells (MCF-7). In order to better predict the efficacy of GEN, we have prepared the Cs/Gel composite scaffolds by 3D printing technology to mimic the MCF-7 cell growth microenvironment. The prepared Cs/Gel scaffold has good mechanical properties and biocompatibility, which can provide a more accurate platform for drug screening. The semi-inhibitory concentration (IC50) evaluated by CCK-8 assay was 16.06 mg/mL (24 h), 14.85 mg/mL (48 h), and 13.14 mg/mL (72 h). After exposed to GEN for 48 h, the cancer cell survival rate reduced from 69.15 +/- 2.86% (13 mg/mL) to 20.97 +/- 3.24% (16 mg/mL). Although the inhibitory effect was weaker in the 3D culture system, it also managed to inhibit cell proliferation and induce cell apoptosis. Besides, Live/Dead staining, Hematoxylin-Eosin (H&E) staining and SEM evaluation were also conducted to estimate the anti-cancer effect of GEN in 2D and 3D cultures. The results indicate that GEN has an anti-cancer effect based on a timeand dose-dependent manner

Toxicological evaluation of ionic liquid in a biological functional tissue construct model based on nano-hydroxyapatite/chitosan/gelatin hybrid scaffolds

The application of ionic liquid is attracting more attentions as green replacement for volatile organic solvents. However, the toxic effects and risks of ionic liquid in different biological systems for human health and environ-ment are poorly evaluated. Among all ionic liquids, 1-ethyl-3-methylimidazolium diethylphosphate ([Emim] DEP-type) ionic liquid is still at the early phase of development, and its toxicity remains unclear. In this study, we fabricated a 3D biological functional tissue construct model based on nano-hydroxyapatite, chitosan and gel-atin hybrid scaffold and evaluated its toxic effects of [Emim]DEP-type ionic liquid. As a control group, the exam-ination of ionic liquid's toxic effects on the pre-osteoblast cell line (MC3T3-E1) was detected in 2D cultures. The MTT assay showed that [Emim]DEP-type ionic liquid inhibited the proliferation of cells on both 2D cultures and 3D tissue constructs. This effect was correlated with culturing time and concentration, while the IC50 on 3D scaf-folds (12,566, 9015, 7896 mu g/mL, at 24 h, 48 h and 72 h, respectively) was found significantly higher compared to 2D cultures (3959, 2226,1884 mu g/mL). Flow cytometry analysis and scanning electron microscope demonstrated that when [Emim]DEP-type ionic liquid acted on MC3T3-E1 cells for 48 h, the shape of 2D cells shrank, together with decreased surface adhesion. (C) 2020 Published by Elsevier B.V

Fabrication and Cell Responsive Behavior of Macroporous PLLA/Gelatin Composite Scaffold with Hierarchical Micro-Nano Pore Structure

Scaffolds providing a 3D environment which can effectively promote the adhesion, proliferation and differentiation of cells are crucial to tissue regeneration. In this study, the poly-l-lactic acid (PLLA) scaffold with hierarchical pore structural was fabricated via two-step thermally induced phase separation (TIPS). To mimic both physical architecture and chemical composite of natural bone extracellular matrix (ECM), gelatin fibers were introduced into the pores of PLLA scaffolds and formed 3D network structure via TIPS. Human adipose tissue-derived stem cells (ADSCs) were harvested and seeded into PLLA/gel hybrid scaffolds and cultured in vitro for biocompatibility assay. The surface morphology, porosity and compressive modulus of scaffolds were characterized by scanning electron microscopy (SEM), density analysis and compression test respectively. The results showed that hybrid scaffolds had high porosity (91.62%), a good compressive modulus (2.79 ± 0.20 MPa), nanometer fibers (diameter around 186.39~354.30 nm) and different grades of pore size from 7.41 ± 2.64 nm to 387.94 ± 102.48 nm. The scaffolds with mild hydrolysis by NaOH were modified by 1-ethyl-3-(3-dimethyl ami-nopropyl) carbodiimide/N-hydroxysuccinimide (EDC/NHS). Gelatin was performed onto PLLA scaffold via TIPS aiming at enhancement cell-material interaction. In comparison with PLLA scaffold, the PLLA/gel scaffold had better biological performance and the mechanical properties because the gelatin fibers homogeneously distributed in each pore of PLLA scaffold and formed 3D network structure.Published versio

Decellularized Pig Kidney with a Micro-Nano Secondary Structure Contributes to Tumor Progression in 3D Tumor Model

In spite of many anti-cancer drugs utilized in clinical treatment, cancer is still one of the diseases with the highest morbidity and mortality worldwide, owing to the complexity and heterogeneity of the tumor microenvironment. Compared with conventional 2D tumor models, 3D scaffolds could provide structures and a microenvironment which stimulate native tumor tissues more accurately. The extracellular matrix (ECM) is the main component of the cell in the microenvironment that is mainly composed of three-dimensional nanofibers, which can form nanoscale fiber networks, while the decellularized extracellular matrix (dECM) has been widely applied to engineered scaffolds. In this study, pig kidney was used as the source material to prepare dECM scaffolds. A chemical crosslinking method was used to improve the mechanical properties and other physical characteristics of the decellularized pig kidney-derived scaffold. Furthermore, a human breast cancer cell line (MCF-7) was used to further investigate the biocompatibility of the scaffold to fabricate a tumor model. The results showed that the existence of nanostructures in the scaffold plays an important role in cell adhesion, proliferation, and differentiation. Therefore, the pig kidney-derived matrix scaffold prepared by decellularization could provide more cell attachment sites, which is conducive to cell adhesion and proliferation, physiological activities, and tumor model construction

A biological functional hybrid scaffold based on decellularized extracellular matrix/gelatin/chitosan with high biocompatibility and antibacterial activity for skin tissue engineering

Nowadays, decellularized extracellular matrix (dECM) has received widespread attention due to its diversity in providing the unique structural and functional components to support cell growth, and finding material with good biocompatibility and anti-infection capability for skin tissue engineering is still a challenge. In this study, a novel dECM/Gel/CS scaffold with appropriate mechanical strength, good antibacterial activity and high biocompatibility was prepared using a one-pot method. The results showed that the immune components such as cells and DNA (about 98.1%) were successfully removed from the porcine skin tissue. The dECM/Gel/CS scaf-folds exhibited an interconnected pore structure and had a high porosity (>90%) to promote cell growth. Moreover, the appropriate elastic modulus (>482.17 kPa) and degradability (>80.04% for 15 days) of the scaffolds offered stout "houses" for cell proliferation and suitable degradation rate to match the new tissue formation in skin tissue engineering. Furthermore, the addition of chitosan endowed the scaffold with good antibacterial activity, water and protein absorption capacity to avoid wound infection, and maintain the mois-ture and nutrition balance. In vitro cytocompatibility studies showed that the presence of dECM effectively enhanced the cell proliferation. Overall, the advanced dECM/Gel/CS scaffold has considerable potential to be applied in skin tissue engineering

Evaluation of anti-tumor effects of crocin on a novel 3D tissue-engineered tumor model based on sodium alginate/gelatin microbead

Crocin, as one of the biologically active components of saffron, has anti-inflammatory, anti-oxidant, antidepressant and auxiliary anti-tumor effects. Studies have shown that crocin could promote breast cancer cell apoptosis. However, conventional methods are mainly based on two-dimensional (2D) cell culture models, which are difficult to reproduce the tumor environment in vivo due to space constraints. In this study, we prepared a three-dimensional (3D) cell model in vitro based on sodium alginate/gelatin to evaluate the inhibitory effect of crocin on MCF-7 cells, which could bridge the gap in crocin drug evaluation between 2D and 3D cell model in vitro. Different from the 2D culture, the cells were found to aggregate in a spherical shape in the 3D microgel beads. And the CCK-8 assay showed that the growth of MCF-7 cells exposed to crocin was inhibited in a time-related and concentration-related manner. Compared with 2D culture (IC50 that MCF-7 cells treated with crocin at 24 h, 48 h. 72 h: 3.68, 2.55 and 1.53 mg/mL, respectively), the IC50 value of 3D culture (IC50 that MCF-7 cells treated with crocin at 24 h, 48 h, 72 h: 10.12, 6.89 and 6.64 mg/mL, respectively) was significantly increased by 2.77, 2.70, 4.34 times, respectively. Besides, live/dead staining and scanning electron microscope (SEM) revealed that the 2D cultured cells shrank and ruptured after crocin treatment, and the number of living cells was considerably reduced: the size of the cell colonies in the 3D microgel beads decreased. (C) 2021 Published by Elsevier B.V