High-Throughput Screening of Acyl-CoA Thioesterase I Mutants Using a Fluid Array Platform

Screening target microorganisms from a mutated recombinant library plays a crucial role in advancing synthetic biology and metabolic engineering. However, conventional screening tools have several limitations regarding throughput, cost, and labor. Here, we used the fluid array platform to conduct high-throughput screening (HTS) that identified Escherichia coli ???TesA thioesterase mutants producing elevated yields of free fatty acids (FFAs) from a large (106) mutant library. A growth-based screening method using a TetA-RFP fusion sensing mechanism and a reporter-based screening method using high-level FFA producing mutants were employed to identify these mutants via HTS. The platform was able to cover >95% of the mutation library, and it screened target cells from many arrays of the fluid array platform so that a post-analysis could be conducted by gas chromatography. The ???TesA mutation of each isolated mutant showing improved FFA production in E. coli was characterized, and its enhanced FFA production capability was confirmed

Studies on the Performance of Organic Rankine Cycle Applied to Low Temperature Heat Source below 100℃

학위논문 (석사)-- 서울대학교 대학원 : 기계항공공학부, 2016. 2. 김민수.In this study, the performance of Organic Rankine Cycle (ORC) applied to low temperature heat source was investigated to provide meaningful information and better understanding on ORC. In previous studies of ORC, the types of heat source were mainly geothermal heat, solar heat, biomass combustion waste heat whose temperatures range from 150℃ to 350℃. However, although waste heat below 100℃ generated from industrial process (e.g. food, beverage, fiber industry) and PEM fuel cell has a large portion of overall waste heat, it isnt sufficiently utilized for waste heat recovery. Therefore, it is necessary to investigate operating characteristics of ORC using waste heat from heat source under 100℃. In order to verify the performance of ORC applied to heat source below 100℃, experiment was conducted to investigate the effects of some key parameters (e.g. evaporation pressure, condensation pressure, mass flow rate, etc.) and the optimal operating condition which has maximum generation work. Results show that the maximum generation work was about 234 W and the thermal efficiency of ORC was about 4%, when the range of heat input was from 3 kW to 6 kW. By experiment of ORC applied to low temperature heat source, it was confirmed that ORC can obtain the additional generating power from waste heat under 100℃.Chapter 1. Introduction 1 1.1 Background of the Study 1 1.2 Overview on the Organic Rankine Cycle 4 1.3 Literature Survey 9 1.4 Motivation and Objective of the Study 12 Chapter 2. Experimental Setup and Mesurements 16 2.1 Selection of the Working Fluid 16 2.1.1 Cycle Analysis 16 2.1.2 Result and Discussion of Cycle Analysis 21 2.2 Experimental System 23 2.2.1 Gear Pump 25 2.2.2 Scroll Expander 28 2.2.3 Heat Exchangers 31 2.2.4 Auxiliary Components and Measurements 33 Chapter 3. Experimental Results and Discussions 38 3.1 Experimental Procedure and Conditions 38 3.1.1 Data Reduction 38 3.1.2 Experimental Conditions 41 3.2 Performance of the Gear Pump 45 3.3 Performance of the Scroll Expander 50 3.4 Performance of the Overall System 60 3.4.1 Energetic analysis of the overall system 60 3.4.2 Exergetic analysis of the overall system 77 Chapter 4. Conclusion 81 References 83 Abstract (in Korean) 87Maste

Research Update: Strategies for efficient photoelectrochemical water splitting using metal oxide photoanodes

Photoelectrochemical (PEC) water splitting to hydrogen is an attractive method for capturing and storing the solar energy in the form of chemical energy. Metal oxides are promising photoanode materials due to their low-cost synthetic routes and higher stability than other semiconductors. In this paper, we provide an overview of recent efforts to improve PEC efficiencies via applying a variety of fabrication strategies to metal oxide photoanodes including (i) size and morphology-control, (ii) metal oxide heterostructuring, (iii) dopant incorporation, (iv) attachments of quantum dots as sensitizer, (v) attachments of plasmonic metal nanoparticles, and (vi) co-catalyst coupling. Each strategy highlights the underlying principles and mechanisms for the performance enhancements.open2

Lymphangiography to treat postoperative lymphatic leakage: a technical review.

In addition to imaging the lymphatics and detecting various types of lymphatic leakage, lymphangiography is a therapeutic option for patients with chylothorax, chylous ascites, and lymphatic fistula. Percutaneous thoracic duct embolization, transabdominal catheterization of the cisterna chyli or thoracic duct, and subsequent embolization of the thoracic duct is an alternative to surgical ligation of the thoracic duct. In this pictorial review, we present the detailed technique, clinical applications, and complications of lymphangiography and thoracic duct embolization