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Articles 1561 - 1590 of 2554
Full-Text Articles in Engineering
Efficiency On Extending The Shelf-Life Of Ripened Mango (Cv. Golden Nam Dokmai) Using Bioplastic Bags From Laboratory Scale And Industrial Scale, Tanudkid Butweangphant
Efficiency On Extending The Shelf-Life Of Ripened Mango (Cv. Golden Nam Dokmai) Using Bioplastic Bags From Laboratory Scale And Industrial Scale, Tanudkid Butweangphant
Chulalongkorn University Theses and Dissertations (Chula ETD)
Efficiency in extending the shelf-life of ripened Golden Nam Dokmai by using bioplastic bags from laboratory scale and industrial scale production was tested. Polylactic acid (PLA) pellets and various fillers were mixed via twin screw extruder before being blown into film via extruder attached to blown film die in laboratory scale and industrial scale equipment. Oxygen and water vapor permeability of both kinds of bioplastic bags were evaluated for used as modified atmosphere packaging, for extend shelf-life of ripened mango. The oxygen permeability of films was 1,635.59±87.75 and 1,250.64±96.42 cc/m2-day and their water vapor permeability was 165.26±5.74 and 240.45±57.76 g/m2-day …
Modeling Production Of Aromatic From N-Paraffins With Chemical Equilibria, Thidarat Detsut
Modeling Production Of Aromatic From N-Paraffins With Chemical Equilibria, Thidarat Detsut
Chulalongkorn University Theses and Dissertations (Chula ETD)
Chemical Equilibrium models were constructed for modeling and developing the aromatic production model from the normal paraffin at the equilibrium of the reaction with catalysts, i.e. ZSM-5(80) and Mo2C. The models were verified under operating temperatures of 450-500 ° C under atmospheric pressure at 1 atm. By examining the accuracy by comparing the data calculated from each model with the value obtained from the corresponding experiments at the condition that the reaction is balanced. The suitable equilibrium model depends on the type of catalyst used in the system. The accuracy of all equilibrium models could be improved by specifying the …
The Synthesis Of Hyperbranched Epoxy Resin For Improvement Of Thermal, Mechanical, And Adhesion Properties Of Epoxy Adhesive, Tossapol Boonlert-Uthai
The Synthesis Of Hyperbranched Epoxy Resin For Improvement Of Thermal, Mechanical, And Adhesion Properties Of Epoxy Adhesive, Tossapol Boonlert-Uthai
Chulalongkorn University Theses and Dissertations (Chula ETD)
This research aimed to synthesize and characterize the hyperbranched epoxy resin synthesized by A2 + B4 polycondensation reaction consisting of bisphenol A (BPA) and polyethylene glycol (PEG) as A2 monomers, pentaerythritol as B4 branching monomer, and epoxide end group. There were varying PEG contents of 0, 5, 10, and 15 wt% of BPA. It was found that the synthesized resins could be confirmed by identifying the important chemical bond and possible structure by Fourier-transform infrared spectroscopy (FTIR) and H- and 13C-nuclear magnetic resonance (H-NMR and 13C-NMR) techniques. The 13C-NMR technique could identify the degree of branching (DB) of the synthesized …
Separation Of Trace Palladium Chloro Complexes From Wastewater Of Electroless Plating Process Via Hollow Fiber Supported Liquid Membrane, Vanee Mohdee
Chulalongkorn University Theses and Dissertations (Chula ETD)
The separation of palladium (Pd (II)) from wastewater containing copper (Cu (II)) and nickel (Ni (II)) is investigated via hollow fiber supported liquid membrane (HFSLM). The viability to separate Pd (II) was established by controlling the influence of operating conditions viz. aqueous feed acidity, carrier concentration, types of stripping solution as well as flows rate of feed and stripping solutions. A complete separation of Pd (II) acheiving >99% extraction and 87.09% recovery was demonstrated under optimum conditions of 6%(v/v) Aliquat 336, pH 2 as aqueous feed acidity, 0.5 M thiourea mixed with 0.1 M HCl as a strippant and 100 …
Non-Faradaic Electrochemical Modification Of Catalytic Activity (Nemca) Of Propane Oxidation On Pt/Ysz Thin Film Cell, Wanchana Lelalertsupakul
Non-Faradaic Electrochemical Modification Of Catalytic Activity (Nemca) Of Propane Oxidation On Pt/Ysz Thin Film Cell, Wanchana Lelalertsupakul
Chulalongkorn University Theses and Dissertations (Chula ETD)
In this work, non-Faradaic Electrochemical Modification of Catalytic Activity (NEMCA) of propane oxidation over Pt/yttria-stabilized zirconia (YSZ) thin films on alumina substrates has been studied. YSZ thin films were initially prepared by slurry dip coating and calcined at a relatively lower temperature of 800 oC. Propane oxidation at temperatures in a range of 300-500 oC clearly exhibited NEMCA. The maximum rate enhancement ratio was close to 3 at an applied potential of 1.0 V and a reaction temperature of 400 oC. The maximum faradaic efficiency was higher than 10,000 at an applied potential of 0.2 V and 300oC. However, NEMCA …
Synthesis Of Ziegler-Natta Catalysts Containing Sicl4/Teos/Ticl4/Mgcl2 For Ethylene/1-Hexene Copolymerization, Wasinee Ousirisombat
Synthesis Of Ziegler-Natta Catalysts Containing Sicl4/Teos/Ticl4/Mgcl2 For Ethylene/1-Hexene Copolymerization, Wasinee Ousirisombat
Chulalongkorn University Theses and Dissertations (Chula ETD)
Polyethylene (PE) is still worldwide manufacturing, and its most productivity is in Asia. The main categories of PE including high density polyethylene (HDPE), low density polyethylene (LDPE) and linear low density polyethylene (LLDPE). Ziegler-Natta catalyst is catalyst that used for α-olefins polymerization and it is widely used in industry because it has good activity with low operating cost. This research studies on synthesized SiCl4/TEOS/TiCl4/MgCl2 Ziegler-Natta catalyst in ethylene/1-hexene copolymerization with added silicon compounds,including tetraethylorthosilicate (TEOS) and SiCl4, used as additive in catalyst by varying 1-hexene comonomer at 0%, 3% and 5%. This research is separated into 2 parts, the first …
Performance Analysis Of The Proton-Conducting Solid Oxide Electrolysis Cell Coupling With Dry Methane Reforming, Wissawa Chalee
Performance Analysis Of The Proton-Conducting Solid Oxide Electrolysis Cell Coupling With Dry Methane Reforming, Wissawa Chalee
Chulalongkorn University Theses and Dissertations (Chula ETD)
The proton-conducting solid oxide electrolysis cell (H-SOEC) is a clean technology for syngas production from H2O and CO2 through electrochemical and chemical reactions. However, it gives low CO2 conversion and produces syngas product with high H2O content. Therefore, the H-SOEC coupling with a dry methane reforming process (H-SOEC/DMR) is proposed to improve its performance. The process flowsheet of the H-SOEC/DMR is developed by using Aspen Plus and used to evaluate the performance of H-SOEC/DMR. The performance analysis of the H-SOEC/DMR shows that under the temperature range of 1073-1273 K, the %CO2 and %CH4 conversions of higher than 90% and 80% …
Development Of Nickel Alloy Hydrogen Electrodes For Solid Oxide Electrolysis Cell, Aritat Wongmaek
Development Of Nickel Alloy Hydrogen Electrodes For Solid Oxide Electrolysis Cell, Aritat Wongmaek
Chulalongkorn University Theses and Dissertations (Chula ETD)
The conventional nickel-yttrium stabilized zirconia (Ni-YSZ) cathode in solid oxide electrolysis cell (SOEC) suffers from oxidation after exposed to steam during electrolysis for hydrogen production. The Ni-chromium (Cr)-iron (Fe) alloys with various compositions are introduced to improve cathode oxidation resistance. This study aims to study the effect of alloy contents and determine suitable fabrication method for SOEC cathode. The alloy containing cathode should satisfy both high electrochemical performance and low degradation rate. The content of Fe and Cr are varied in the range of 0-20%wt when the weight ratio of metal to YSZ is maintained constantly at 60:40. The SOEC …
Wind Load Analysis Of A High-Rise Building By Computational Fluid Dynamics, Canh Thiet Phung
Wind Load Analysis Of A High-Rise Building By Computational Fluid Dynamics, Canh Thiet Phung
Chulalongkorn University Theses and Dissertations (Chula ETD)
As new buildings become taller due to limited land area, often irregular in shapes for esthetics and some design constraints, wind load formula provided in design codes/standards cannot be applied because of the limitations. Wind tunnel test (WTT) is thus the suggested approach to obtain appropriate wind load for the design of such buildings. However, WTT is costly and time-consuming as it often requires much preparation of the small-scale model of the target building, instrumentation, and numerous realistic blocks of surrounding buildings (SBs). In this study, the CFD's accuracy will be evaluated by comparing its results to WTT by a …
Shear Wave Velocity Measurement Of Bangkok Clay Under Triaxial Testing With Various Stress Paths, Sirichai Pethrung
Shear Wave Velocity Measurement Of Bangkok Clay Under Triaxial Testing With Various Stress Paths, Sirichai Pethrung
Chulalongkorn University Theses and Dissertations (Chula ETD)
Orientation paths of shear wave velocity for clayey soil subjected to multiple triaxial loading tests are dependent on complicated factors direction of stresses, void ratio, coefficient of earth pressure at rest, etc. However, most suggested the mean effective stress could provide a suitable correlation as well. In the present study, an identify the shear wave velocity under triaxial undrained small loading-unloading test , monotonic triaxial drained compression test , triaxial drained loading-unloading test , triaxial stress control test , drained triaxial extension , and undrained triaxial extension measured using the bender elements was presented. These results are indicated that the …
Seismic Enhancement Of Reinforced Concrete Columns With Lap Splices Using External Steel Collars, Pochara Kruavit
Seismic Enhancement Of Reinforced Concrete Columns With Lap Splices Using External Steel Collars, Pochara Kruavit
Chulalongkorn University Theses and Dissertations (Chula ETD)
This research investigated the behavior of reinforced concrete (RC) columns with lap splices and mechanical splices. The study conducted the full-scale test and predicted a lateral load capacity using the proposed numerical model. The test configuration was a cantilever column subjected to a cyclic lateral loading and a constant gravity load. The tested specimens consisted of the RC column without lap splices, RC columns with spliced reinforcement including lap splices and mechanical splices, and RC column with lap splices strengthened by external steel collars. The experimental result indicated that the lateral load capacity of the RC column with mechanical splices …
Modified Response Spectrum Analysis For Computing Seismic Demands Of Multi-Tower Building Sharing A Common Podium, Tarek Youssef
Modified Response Spectrum Analysis For Computing Seismic Demands Of Multi-Tower Building Sharing A Common Podium, Tarek Youssef
Chulalongkorn University Theses and Dissertations (Chula ETD)
To design irregular tall buildings, performance-based design (PBD) approach, which requires nonlinear response history analysis (NLRHA), is the most accurate method. However, PBD approach is not always used in the current design practice because of its complexity, and as allowed in ASCE 7-16, design engineer can use code-based approach such as response spectrum analysis (RSA) procedure. This paper aims to investigate the accuracy of RSA procedure when applied to irregular tall buildings, and in particular for multi-tower buildings sharing a common podium. Also, a modified response spectrum analysis (MRSA) procedure previously proposed for computing shear demand in regular tall buildings, …
A Study On Intermediate Debonding For Steel Beams Strengthened With Fiber Reinforced Polymer Plates, Tosporn Prasertsri
A Study On Intermediate Debonding For Steel Beams Strengthened With Fiber Reinforced Polymer Plates, Tosporn Prasertsri
Chulalongkorn University Theses and Dissertations (Chula ETD)
There are limited previous works focusing on the occurrence of intermediate debonding in steel beams strengthened with fiber reinforced polymer (FRP) plates. Tested beams in the past experiments invoked an intermediate debonding by creating notch in steel beams. An anchorage system at FRP termination points was installed on some tested beams in literature. This research uses an initial bond defect to induce an intermediate debonding at the FRP-steel interface. The bond behavior of FRP-steel interface was investigated through the FRP-steel joints under the single lap shear testing. A four-point bending test was conducted to examine the flexural properties of FRP-strengthened …
An Application Of Line Of Balance And Building Information Modeling For Optimal Resource And Schedule: A Case Study Of An Elevated Highway Construction, Thanakon Uthai
Chulalongkorn University Theses and Dissertations (Chula ETD)
Project scheduling is an essential tool to support construction operations completing the project under limited time and cost. The linear infrastructure project such as elevated highway construction involves a large scale of working area and complexity of management. Recently, schedules are planned manually based on planners’ experience and intuition which may consume time and lead to human-errors. Moreover, the presentations of schedule by using the existing methods dose not cover the overview of projects in various aspects. The objective of this research is to establish an application of Line of Balance (LOB) and Building Information Modeling (BIM) for optimal resource …
Fundamental Solutions Of Multi-Layer Elastic Media With Couple Stress Theory, Wipavee Wongviboonsin
Fundamental Solutions Of Multi-Layer Elastic Media With Couple Stress Theory, Wipavee Wongviboonsin
Chulalongkorn University Theses and Dissertations (Chula ETD)
This thesis presents fundamental solutions of a two-dimensional, elastic, multi-layered medium under surface loadings by taking the influence of material micro-structure into account. An underlying mathematical model for simulating such small-scale influence is established within the continuum-based framework via the well-known couple stress theory. For each material layer, the generalized Navier’s equation governing the displacement field is established and the method of Fourier integral transform is applied to derive its general solution in a transformed space. A set of boundary conditions and the continuity of fields along the material interfaces are enforced to obtain a system of linear algebraic equations …
The Performance Of Automatic Adaptive Edge-Based Smoothed Finite Element Method In Engineering Mechanics Applications, Vu Hoang Le
The Performance Of Automatic Adaptive Edge-Based Smoothed Finite Element Method In Engineering Mechanics Applications, Vu Hoang Le
Chulalongkorn University Theses and Dissertations (Chula ETD)
The thesis investigates the performance of an edge-based smoothed finite element method (ES-FEM) combined with an automatic mesh refinement (AMR) algorithm to provide the solutions of in-plane elastic engineering mechanics applications. The ES-FEM adopts a strain smoothing technique over the edges adjoining the two adjacent triangular-shape meshes, whilst a layer of singular yet compatible five-node elements in addition to standard three-node ES-FEs can be employed to overcome the problems associated with stress singularity. The proposed framework enables the effective model construction of realistic engineering structures with complex geometry at modest computational resources. The AMR algorithm adopts the newest node bisection …
Strength Analysis Of Concrete-Encased Cellular Steel Columns, Worakarn Anuntasena
Strength Analysis Of Concrete-Encased Cellular Steel Columns, Worakarn Anuntasena
Chulalongkorn University Theses and Dissertations (Chula ETD)
This research investigates the compression behavior of bare cellular steel columns and concrete-encased cellular steel (CECS) columns subjected to concentric and eccentric loadings. First, the experimental study of the cellular steel and CECS columns was conducted in the laboratory. For the cellular steel columns subjected to concentric loading, the failure mode of the bare cellular steel columns was local buckling at both web and flanges at the hole section. All cellular steel columns exhibited yielding and hardening behavior. The cellular columns had the average yield loads less than the parent column by 15 %. For the CECS and CES columns …
Thai Spelling Correction And Word Normalization On Social Text Using A Two-Stage Pipeline With Neural Contextual Attention, Anuruth Lertpiya
Thai Spelling Correction And Word Normalization On Social Text Using A Two-Stage Pipeline With Neural Contextual Attention, Anuruth Lertpiya
Chulalongkorn University Theses and Dissertations (Chula ETD)
Text correction systems (e.g., spell checkers) have been used to improve the quality of computerized text by detecting and correcting errors. However, the task of performing spelling correction and word normalization (text correction) for Thai social media text has remained largely unexplored. In this thesis, we investigated how current text correction systems perform on correcting errors and word variances in Thai social texts and propose a method designed for this task. We have found that currently available Thai text correction systems are insufficiently robust for correcting spelling errors and word variances, while the text correctors designed for English grammatical error …
Quantum Comparator Circuit On Superconducting Quantum Computer, Naphan Benchasattabuse
Quantum Comparator Circuit On Superconducting Quantum Computer, Naphan Benchasattabuse
Chulalongkorn University Theses and Dissertations (Chula ETD)
In this thesis, we present an optimised quantum comparator circuit based on Cuccaro's ripple-carry quantum adder using relative phase techniques from Maslov's multiple control Toffoli optimisation. We extend the cost function from simply counting C-Not and Toffoli gate to Qiskit cost which defines arbitrary single qubit gate cost as unity and C-Not as the only two qubit gate cost as ten. We report the comparison result between our comparator circuit with previous comparator circuits from literature using optimal Toffoli implementation with Qiskit cost, C-Not count, and circuit depth. We also report our experiment of implementing a two-bit comparator on IBM …
A Peer-To-Peer Protocol For Prioritized Software Updates On Wireless Sensor Networks, Natchanon Nuntanirund
A Peer-To-Peer Protocol For Prioritized Software Updates On Wireless Sensor Networks, Natchanon Nuntanirund
Chulalongkorn University Theses and Dissertations (Chula ETD)
Software updating is essential for devices in wireless sensor networks for adding new features, improving performance, or patching vulnerabilities. But since some deployed devices are unable to be accessed directly, data dissemination protocol is used for distributing the update to those devices. However, each software updating may have different priority, for instance, an update that adds an optional feature does not have to be applied as fast as an update that patches severe vulnerabilities. This research presents a reliable data dissemination protocol which is configurable for energy-speed trade-off deriving some concepts from BitTorrent such as Handshaking, Segmented File Transfer, and …
Semantic Segmentation On Remotely Sensed Images Using Deep Convolutional Encoder-Decoder Neural Network, Teerapong Panboonyuen
Semantic Segmentation On Remotely Sensed Images Using Deep Convolutional Encoder-Decoder Neural Network, Teerapong Panboonyuen
Chulalongkorn University Theses and Dissertations (Chula ETD)
One of the fundamental tasks in remote sensing is the semantic segmentation of the aerial and satellite images. It plays a vital role in applications, such as agriculture planning, map updates, route optimization, and navigation. The state-of-the-art model is the Deep Convolutional Encoder-Decoder (DCED). However, the accuracy is still limited since the architecture is not designed for recovering low-level features, e.g., river, low vegetation on remotely sensed images, and the training data in this domain are deficient. In this dissertation, we aim to propose the semantic segmentation architecture in five aspects, designed explicitly for the remotely sensed field. First, we …
Semi-Supervised Deep Learning With Malignet For Bone Lesion Instance Segmentation Using Bone Scintigraphy, Terapap Apiparakoon
Semi-Supervised Deep Learning With Malignet For Bone Lesion Instance Segmentation Using Bone Scintigraphy, Terapap Apiparakoon
Chulalongkorn University Theses and Dissertations (Chula ETD)
One challenge in applying deep learning to medical imaging is the lack of labeled data. Although large amounts of clinical data are available, acquiring labeled image data is difficult, especially for bone scintigraphy (i.e., 2D bone imaging) images. Bone scintigraphy images are generally noisy, and ground-truth or gold standard information from surgical or pathological reports may not be available. We propose a novel neural network model that can segment abnormal hotspots and classify bone cancer metastases in the chest area in a semi-supervised manner. Our proposed model, called MaligNet, is an instance segmentation model that incorporates ladder networks to harness …
Electro-Deposited Polyaniline On Tio2 As A Photoanode For Improved Photoelectrochemical Performance In Water Oxidation And Methylene Blue, Reeda Jamsri
Chulalongkorn University Theses and Dissertations (Chula ETD)
Polyaniline (PANI) deposited on TiO2 as a photoanode has been synthesized by the electro-polymerization method. The electrodeposition was performed in aqueous solutions containing 0.5 M aniline and 1 M H2SO4 at a constant current density. The photoanode demonstrated its potential applications for photocatalytic degradation of methylene blue dye (MB) and photoelectrochemical (PEC) water splitting. A ~2.7 fold enhancement in the photodegradation activity at 0.9V vs. Ag/AgCl of a bias voltage and the high water oxidation photocurrent density of PANI/TiO2 on FTO photoanode achieves 1.3 mA cm-2 at 0.6V vs. Ag/AgCl under illumination which is higher than that pure TiO2 on …
Incorporating Air-Conditioning Monitoring And Control In Building Energy Management Systems Using Data Science Approach, Pornpra Chumnanvanichkul
Incorporating Air-Conditioning Monitoring And Control In Building Energy Management Systems Using Data Science Approach, Pornpra Chumnanvanichkul
Chulalongkorn University Theses and Dissertations (Chula ETD)
This thesis proposes an analytic and control algorithm for a split-type air conditioner (AC) in building energy management systems (BEMS) using data science approach. Available data used in this research are from three sources including Chulalongkorn University Building Energy Management Systems (CUBEMS), Chulalongkorn University Solar Forecast (CUSF) platform and Thai Meteorological Department (TMD). Measured AC power consumption and measured indoor zonal temperature are obtained from CUBEMS. Outdoor weather data are obtained from CUSF platform and TMD. The main procedure of this work can be divided into three processes: four-level AC classification, AC power baseline modeling, and hybrid AC control algorithm. …
กัมมันตภาพและเสถียรภาพของ Ptiro2 รองรับด้วยท่อนาโนคาร์บอนที่หุ้มพอลิแอนิลีนสำหรับเซลล์เชื้อเพลิงพีอีเอ็มแบบผันกลับได้, ลดาวรรณ์ ธูปชัย
กัมมันตภาพและเสถียรภาพของ Ptiro2 รองรับด้วยท่อนาโนคาร์บอนที่หุ้มพอลิแอนิลีนสำหรับเซลล์เชื้อเพลิงพีอีเอ็มแบบผันกลับได้, ลดาวรรณ์ ธูปชัย
Chulalongkorn University Theses and Dissertations (Chula ETD)
งานวิจัยนี้เป็นการศึกษาผลของตัวรองรับต่อกัมมันตภาพและเสถียรภาพของตัวเร่งปฏิกิริยาแพลทินัมอิริเดียมออกไซด์ในเซลล์เชื้อเพลิงพีอีเอ็มแบบผันกลับได้ ตัวรองรับที่ใช้ในการทดสอบ ได้แก่ คาร์บอนวัลแคน (C) ท่อนาโนคาร์บอน (CNTs) และท่อนาโนคาร์บอนที่หุ้มพอลิแอนิลีน (CNTs-PANI) พบว่าตัวเร่งปฏิกิริยา PtIrO2/CNTs-PANI มีกัมมันตภาพในการเร่งปฏิกิริยามากที่สุดทั้งในปฏิกิริยารีดักชันของออกซิเจนและปฏิกิริยาการเกิดออกซิเจน โดยความหนาแน่นเชิงจลนพลศาสตร์สำหรับปฏิกิริยารีดักชันของออกซิเจน ที่ 0.6 โวลต์เทียบกับศักย์ไฟฟ้ามาตรฐานคาโลเมล เท่ากับ 1.24 มิลลิแอมแปร์ต่อตารางเซนติเมตร และปฏิกิริยาการเกิดออกซิเจน ที่ 1.55 โวลต์เทียบกับศักย์ไฟฟ้ามาตรฐานคาโลเมล เท่ากับ 41.36 มิลลิแอมแปร์ต่อตารางเซนติเมตร หลังผ่านการทดสอบเสถียรภาพในสารละลายกรดซัลฟิวริก จำนวน 1000 รอบ พบว่าตัวเร่งปฏิกิริยา PtIrO2/CNTs-PANI มีการลดลงของความหนาแน่นกระแสไฟฟ้าและอัตราการลดลงของพื้นที่ผิวในการเกิดปฏิกิริยาน้อยที่สุด ทั้งในปฏิกิริยารีดักชันของออกซิเจนและปฏิกิริยาการเกิดออกซิเจน เนื่องจากพอลิแอนิลีนที่เติมลงไปช่วยในการยึดเกาะระหว่างตัวเร่งปฏิกิริยาและตัวรองรับ ทำให้ตัวเร่งปฏิกิริยากระจายตัวได้ดีและมีเสถียรภาพ จากผลการทดลองข้างต้น พบว่าตัวเร่งปฏิกิริยา PtIrO2/CNTs-PANI เหมาะสมสำหรับการเร่งปฏิกิริยาทั้งในปฏิกิริยารีดักชันของออกซิเจนและปฏิกิริยาการเกิดออกซิเจน เพื่อใช้เป็นตัวเร่งปฏิกิริยาแบบสองหน้าที่สำหรับเซล์เชื้อเพลิงพีอีเอ็มแบบผันกลับได้
การจัดการวัฏจักรไนโตรเจนและฟอสฟอรัสในระบบอควาโปนิกส์, ศิริวณี สุภาจารุวงศ์
การจัดการวัฏจักรไนโตรเจนและฟอสฟอรัสในระบบอควาโปนิกส์, ศิริวณี สุภาจารุวงศ์
Chulalongkorn University Theses and Dissertations (Chula ETD)
การวิจัยนี้มีวัตถุประสงค์เพื่อศึกษาบทบาทของกระบวนการไนตริฟิเคชันในระบบอควาโปรนิกส์ โดยแบ่งการทดลองออกเป็น 3 ส่วน ได้แก่ 1) ศึกษาอัตราการใช้แอมโมเนียและไนเตรทของผักสลัดกรีนโอ๊ค 2) ศึกษาการออกแบบและการทางานของส่วนบำบัดไนตริฟิเคชันสาหรับระบบเลี้ยงสัตว์น้ำแบบปิด และ 3) ศึกษาการประเมินประสิทธิภาพการบำบัดสารประกอบอนินทรีย์ไนโตรเจนและฟอสฟอรัสในระบบเลี้ยงสัตว์น้าแบบปิดที่ทางานร่วมกับระบบอควาโปนิกส์ที่มีและไม่มีการติดตั้งส่วนบำบัดไนตริฟิเคชัน จากการทดลองพบว่า ผักสลัดกรีนโอ๊คสามารถดูดซึมได้ทั้งแอมโมเนียและไนเตรทไปใช้ในการเจริญเติบโต อย่างไรก็ตามพืชจะเลือกใช้แอมโมเนียก่อนไนเตรท ทาให้การดูดซึมไนเตรทสามารถพบได้หลังจากที่แอมโมเนียในระบบหมดลง สำหรับการเพิ่มการสะสมตัวของไนเตรทในระบบเลี้ยงสัตว์น้ำแบบปิดที่ทำงานร่วมกับระบบอควาโปนิกส์สามารถทำได้โดยการติดตั้งส่วนแยกตะกอนและส่วนบำบัดไนตริฟิเคชันด้วยตัวกรองชีวภาพแบบเคลื่อนที่ลงในชุดทดลอง จากการทดลองพบว่าระบบมีอัตราการบำบัดแอมโมเนียเท่ากับ 1.09 มก./ล. และเกิดการเติมอากาศอย่างสมบูรณ์เพื่อเพิ่มประสิทธิภาพการบำบัดไนตริฟิเคชัน โดยเป็นไปตามความคาดหมายว่าในระบบที่มีการติดตั้งส่วนบำบัดไนตริฟิเคชันพบความเข้มข้นของไนเตรทสูงกว่า อย่างไรก็ตามในการเดินระบบเลี้ยงสัตว์น้ำแบบปิดร่วมกับระบบอควาโปนิกส์ในระยะยาว พบว่าการบำบัดไนตริฟิเคชันที่เกิดขึ้นตามธรรมชาติในบ่อเลี้ยงปลาและรางปลูกผักเพียงพอที่จะทำให้เกิดกระบวนการบำบัดอย่างสมบูรณ์เมื่อทำการเดินระบบประมาณ 20 วัน
Rice Granules As Natural Carrier To Encapsulate Drug And Aromatic Oils, Xue Liu
Rice Granules As Natural Carrier To Encapsulate Drug And Aromatic Oils, Xue Liu
Chulalongkorn University Theses and Dissertations (Chula ETD)
Rice granules as major energy supply to humanity worldwide are utilized in many fields, such as food, medical, printing and plastic industries. In this thesis work, rice starch/granule is applied as hydrophilic drug (vancomycin) carrier to achieve the release. By confirmation on the stability of rice granules against to various treatments like alkali, acid and heating, as well as a-amylase, trypsin, and lipase, it is possible to use rice granules as 100% natural source to be the capsule and matrix getting the non-core-shell structure of the formation. The success of encapsulation is confirmed by the observations on crystalline, thermal properties …
Effects Of Titanium Content In Ziegler-Natta Catalyst On The Reducibility Of Triethylaluminum Cocatalyst, Pichayapong Sitthijun
Effects Of Titanium Content In Ziegler-Natta Catalyst On The Reducibility Of Triethylaluminum Cocatalyst, Pichayapong Sitthijun
Chulalongkorn University Theses and Dissertations (Chula ETD)
The Ziegler-Natta catalytic system for olefin polymerization comprises the TiCl4 precursor adsorbed on MgCl2 support and reacted with an alkylating agent to generate active sites. The reduction of TiCl4 valence plays a crucial role in the formation of Ti3+ and Ti2+ active species for ethylene polymerization whereas only Ti3+ active for propylene polymerization. Thus, the reducibility of Ti-based catalyst using AlEt3 cocatalyst was studied during ethylene and propylene polymerization which has not been previously studied yet. For this study, the effect of Ti content on the reducibility was considered through the changing of catalytic activity with the increase of AlEt3 …
Roles Of Wox On Pt/Γ-Al2o3 Catalysts On The Prevention Of Pt Metal Sintering During Hydrogenolysis Of Glycerol To 1,3-Propanediol, Poonnapa Limsoonthakul
Roles Of Wox On Pt/Γ-Al2o3 Catalysts On The Prevention Of Pt Metal Sintering During Hydrogenolysis Of Glycerol To 1,3-Propanediol, Poonnapa Limsoonthakul
Chulalongkorn University Theses and Dissertations (Chula ETD)
Hydrogenolysis of glycerol to produce 1,3-propanediol is the most effective reaction which conversing excess glycerol from biodiesel production to high-value-add product ; especially, 1,3-propanediol. A solid catalyst which generally used as selective to 1,3-propanediol production is Pt-based catalyst with γ-Al2O3 supporter which was prepared by wet impregnation method in this study. Although hydrogenolysis of glycerol reaction has been carried out under mild conditions: 140 °C and 5 bar of initial H2 pressure, the deactivation of non-reduced Pt/γ-Al2O3 catalyst is observed. To investigate the deactivation of the catalyst, the used Pt/γ-Al2O3 and Pt/WOx/γ-Al2O3 catalysts were characterized by N2-physisorption, ICP-OES, SEM-EDX, XRD, …
Selective Oxidation Of H2s In Biogas To Sulfur On V2o5 Catalyst Dispersedon Ceo2-Mo2 (M = Ti, Si, Zr) Mixed Oxides, Benjamaporn Tudkesorn
Selective Oxidation Of H2s In Biogas To Sulfur On V2o5 Catalyst Dispersedon Ceo2-Mo2 (M = Ti, Si, Zr) Mixed Oxides, Benjamaporn Tudkesorn
Chulalongkorn University Theses and Dissertations (Chula ETD)
In this research, the characteristics and catalytic performances of V2O5catalysts supported on mixed oxides CeO2-MO2 (M = Ti, Si, Zr) as compared to the commercial CeO2 supported ones were studied in the selective catalytic oxidation of H2S in biogas to sulfur at 130oC. The mixed-oxide supports were prepared by co-precipitation method with 3 wt.% vanadium loading by wet impregnation method. From the XRD and Raman spectroscopy results, all the catalysts exhibited high dispersion of V2O5 on the supports with the 1:1 molar ratio CeO2-SiO2 mixed oxide showed the highest conversion of H2S at ̴ 73% and low selectivity of SO2 …