Catalytic Reactions for Upgrading Bio-oils and Petroleum Fuels

The increasing consumption and phase-out of conventional fuels has derived the tremendous interest of our society in making uses of renewable energy resources such as biomass. In response to this interest, bio-oil produced from biomass feed stocks has been gradually making its contribution as a part of normal fuels. However, since the bio-oil is not stable due to its high oxygen content, upgrading is necessary to improve its performance. In parallel to the need for sustainable fuel sources, a huge desire in creating more environmentally friendly fuels is generated. For instance, lowering emission for conventional diesel and gasoline fuels has been considered one of the actions to reduce the negative impacts of fuel combustion on human health. From point of view of upgrading petroleum fuels, this could partially mean reduction in aromatic content in both diesel and gasoline. In the scope of this dissertation, the author will present two catalytic strategies to improve the performances of bio-oils and conventional diesel and gasoline fuels. Since the high oxygen content of bio-oils has limited its storage ability and lower its heating content, in some cases, removing oxygen or deoxygenating bio-oil molecules has been proposed as a recommended catalytic reaction. In the first part of the dissertation, the author will focus on the deoxygenation reaction of methyl esters and triglycerides, which can be derived from biomass feed stocks and contain the ester functional group (-COO-) relevant to bio-oil molecules. Hydrocarbons are the desired products from the deoxygenation reactions. The first step in optimizing the yield and selectivity of the hydrocarbons is to establish the reaction mechanisms with all possible reaction pathways leading to formation of hydrocarbons. In addition, the effects of various parameters on the deoxygenation reactions have been examined. The important parameters include pressure, temperature, hydrogen partial pressure, and reactor configuration. Certainly, one cannot exclude the important role of catalysts. The catalysts implemented in these reactions were supported noble-metal-based catalysts such as Pt and Pd. The variation of these parameters will be used in the reactions of several representative molecules such as methyl hexanoate, methyl octanoate, methyl dodecanone, and triacetin. A number of interesting findings on reaction mechanism, catalyst deactivation, and the role of active sites have been drawn from these studies. The second part of this work has touched on the upgrading reactions of aromatics in petroleum fuel. Hydrogenation of the aromatic rings followed by selective ring opening of the corresponding naphthenic compounds has been proposed as one of the strategies to improve the cetane number and other fuel properties. In this work, the ring opening reactions of various naphthenic compounds on different modified Iridium catalysts have been studied. The supported Iridium catalysts are not only active for ring opening reaction but also selective for certain positions of C-C cleavage when supports and additive modifications are applied. Although the two parts of this dissertation deal with different feed molecules, they all bring the common understandings on how to modify the reaction variables to optimize the selective production of hydrocarbon fuels

Investigating the diversity of resistant starch in Vietnamese rice collection

The rapid increase of obesity and type 2 diabetes has recently posed an enormous burden on the healthcare system worldwide. Resistant starch (RS) in rice can escape digestion by enzymes in the small intestine, making its calories unavailable for cells to use. As a result, RS can be used by diabetes patients to prevent diabetes and for obese individuals who do not want extra energy. In our study, 75 Vietnamese rice accessions originating from diverse ecosystems were chosen as plant materials to investigate the diversity of RS content in this collection. The Megazyme kit was used to measure the amount of RS. The release of quinonimine was measured using a spectrophotometer at 510 nm. The results showed that approximately 70% of Vietnamese rice accessions had RS content ranging from 0.015 to 0.2% while only 4% of samples had RS content ranging from 0.6 to 0.8%. The Indica subgroups had significantly higher RS content than the Japonica subgroup. Higher RS content was found in medium- and short- grain rice rather than in long grain. Finally, rice plants grown in rainfed lowlands (RL) and irrigated ecosystems had higher RS content than those grown under mangrove and upland ecosystems. Our results firstly give information about the diversity of RS in Vietnamese rice and secondly may contribute to the field of nutrition by developing a suitable rice-based diet for patients with diabetes or obesity

Učinci zelene prakse restorana na namjeru kupca da kupe ekološki prihvatljive proizvode: Dokazi iz Vijetnama

This research aims to identify how green practices affect customer intention to purchase green products via customers’ emotional attachment. Using the PLS-SEM to analyze 358 restaurant guests to find customer intention to purchase green products is a fundamental constituent of a restaurant’s success. The results reveal that the application of recycling and composting, energy and water management activities have a positive significant impact on customer intention to purchase green products and pro-environmental emotional attachment, and the application of organic food-green products and materials have a significant impact on emotional attachment, but not trigger on customer intention to purchase green products. Meanwhile, the application of eco-friendly supplies did not affect emotional attachment and customer intention to purchase. Pro-environmental emotional attachment is a key mediator of the customer intention model. The results provided both knowledge and theory of green practices by adding customers\u27 emotional attachment into the theory of planned behavior to understand customer behavior toward green restaurants. It proposes managerial recommendations and building strategies for the long term to increase customer intention to purchase green products in the restaurant industry.Cilj je ovog istraživanja utvrditi način na koji zelene prakse utječu na namjeru kupca da kupi ekološke proizvode putem emocionalne povezanosti kupaca. Korištenje PLS-SEM-a za analizu gostiju iz 358 restorana kako bi se utvrdila namjera kupca da kupi ekološke proizvode temeljni je dio uspjeha restorana. Rezultati istraživanja upućuju na to da primjena recikliranja i kompostiranja, aktivnosti gospodarenja energijom i vodama imaju pozitivan utjecaj na namjeru kupca da kupi zelene proizvode i pro-ekološku emocionalnu privrženost te da primjena organske hrane –zelenih proizvoda i materijala na ekološku proizvodnju imaju značajan utjecaj na emocionalnu privrženost, ali ne i na namjeru kupca da kupi zelene proizvode. U međuvremenu, primjena ekološki prihvatljivih zaliha nije utjecala na emocionalnu privrženost i namjeru kupaca za kupnjom. Emocionalna vezanost za zaštitu okoliša ključni je posrednik modela namjere kupaca.Rezultati su osigurali i znanje i teoriju zelene prakse dodajući emocionalnu privrženost kupaca teoriji o planiranom ponašanju kako bi se razumjelo ponašanje kupaca prema zelenim restoranima. Predlažu se menadžerske preporuke i strategije izgradnje za dugoročno povećanje namjere kupca da kupi zelene proizvode u ugostiteljstvu

NGHIÊN CỨU THU NHẬN PROTEIN TỪ CÁM GẠO

Rice bran protein, a plant protein, has been recognized as nutritionally superior to other proteins due on its reported hypoallergenicity and anti-cancer activity. Therefore, it is considered as a promising protein resource applicable in variety of fields such as functional food, cosmetics, livestock and medicine. However, as of now, commercial rice bran protein is not widely available on the market, especially in Vietnam, because of a lack of extraction methods currently in use. In particular, the available methods can not be used to obtain protein isolates of high quality at affordable commercial price. Vietnam is one of the bigest rice export countries in the world, that makes rice bran an abundant agricultural by-product and thus, a readily sufficient source for protein extraction. This study aimed to establish a simple processing method for extraction of high content of protein isolates from rice bran. The obtained results indicated that rice bran was effectively hydrolysed in 20 minutes with α-amylase (Ternamyl) at concentration of 0.25%, pH 7.0 and 90oC. A procedure of 8 steps for protein extraction was given: i) Suspend rice bran in water and stir for 30 minutes at room temperature; ii) Adjust the suspension to pH 9.0 with NaOH 1N and stir for 4 hours; iii) Adjust the suspension to pH 7.0 with HCl 1N, add 0,25% Ternamyl at 90 oC and hydrolyse for 20 minutes; iv) Centrifuge at 4000 rpm for 20 minutes to collect the supernatant; v) Precipitate protein isolates at pH 4.0 by adding HCl 1N; vi) Centrifuge at 4000 rpm for 20 minutes to collect protein isolates; vii) Wash protein isolates twice with water; viii) Dry the isolates at 50oC. The content of protein isolates from this procedure was 41.77% and the yield of processing was 13,41%. The technological indexes including foaming capacity and emulsion activity were 20% and 73.50, respectively, which were higher compared to the same  product from China.Protein cám gạo là loại protein thực vật có giá trị dinh dưỡng vượt trội do có khả năng chống ung thư và không gây dị ứng cho người sử dụng. Vì thế, nó được xem là một protein lương thực cao cấp, có thể ứng dụng trong nhiều lĩnh vực như chăn nuôi, thực phẩm chức năng, thực phẩm dinh dưỡng, mỹ phẩm và y học. Protein này vẫn chưa được thương mại phổ biến trên thị trường, đặc biệt là ở Việt Nam, vì những hạn chế của các phương pháp tách chiết đang sử dụng hiện nay chưa cho phép thu được sản phẩm có chất lượng cao với giá thành phù hợp. Việt Nam là nước sản xuất lúa gạo đứng thứ hai trên thế giới nên nguồn nguyên liệu phụ thải cám gạo cho mục đích tách chiết protein là vô cùng phong phú. Bài báo này trình bày nghiên cứu về xây dựng một quy trình tách chiết protein cám gạo tương đối đơn giản, cho phép thu nhận được protein có hàm lượng tương đối cao. Kết quả nghiên cứu cho thấy α-amylase (Ternamyl) ở nồng độ 0,25%, pH 7.0, nhiệt độ 90­oC, thời gian thủy phân 20 phút có khả năng loại bỏ hiệu quả  tinh bột từ nguyên liệu. Quy trình công nghệ thu nhận protein từ cám gạo xây dựng được gồm 8 bước chính: i) Dịch cám gạo trong nước cất (1:7) được khuấy trong 30 phút; ii) Điều chỉnh dịch cám gạo tới pH 9.0 bằng NaOH 1N và tiếp tục khuấy trong 4 giờ ở nhiệt độ phòng; iii) Điều chỉnh dịch cám gạo về pH 7.0 bằng HCl 1N, bổ sung Termamyl 0,25% ở 90oC và tiến hành thủy phân trong 20 phút; iv) Ly tâm 4000 vòng trong 20 phút để thu dịch trong; v) Tủa protein ở dịch ly tâm bằng HCl 1N tại pH 4.0; vi) Ly tâm thu cặn tủa ở 4000 vòng trong 20 phút; vii) Rửa cặn tủa 2 lần bằng nước khử trùng; viii) Sấy khô mẫu ở 50oC thu protein. Protein thu được từ quy trình này có hàm lượng đạt 41,77% và hiệu suất là 13,41%. Các chỉ số công nghệ của chế phẩm bao gồm độ tạo bọt đạt 20%, độ tạo nhũ tương đạt 73,45, đều cao hơn so với protein đối chứng của Trung Quốc

Carrot hairy roots (Daucus carota L.) characterisation and optimisation for high β‐carotene extraction

Hairy roots are widely known as a biological system for the production of highly diverse biomolecules. β‐carotene – a precursor for vitamin A – is known to be an anti‐oxidant and anti‐gastric cancer and protection agent against cardiovascular disease, heart disease and stroke. β‐carotene has been chemically synthesised and consumed by humans. However, the chemical process often produces a by‐product that may be harmful to human health. Therefore, this study established a protocol to induce hairy roots (HRs) from a Vietnamese carrot variety and produce natural β‐carotene. The Rhizobium rhizogenes ATCC15834 harbouring Ri plasmid and a Vietnamese carrot variety were used as materials for genetic transformation and HR induction studies. The result showed that approximately 50 HR lines were obtained. Culture medium supplemented with 30 mg/L of sucrose that gave the highest biomass of HR was shown in carrot HR line 30, which had a doubling time of 6.5 days. The highest content of β‐carotene extraction, at 128 mg/100g hairy roots, was achieved with a ratio volume (v/v) of 2‐propanol and plant samples of 20:1, followed by two hours’ incubation with 2‐propanol at 60 °C. Our study reveals a highly efficient protocol for Vietnamese carrot hairy root establishment and multiplication. A very efficient protocol for β‐carotene extraction from the hairy root was established to produce natural β‐carotene that achieves the same β‐carotene quantity as that produced by normal roots. This study provides new insight into the production of high‐content and natural β‐carotene for therapeutic application

Investigation of Sodium Manganese Oxide Nanowires Synthesized by Hydrothermal Method for Alkaline Ion Battery

Sodium Manganese Oxide (NaxMnO2) has attracted much attention as cathode materials for alkaline ion battery due to the ability of fast charge and discharge ion Na+, in particular in nanoscale. We report on the synthesis of NaxMnO2 nanowires via hydrothermal synthesis route from Mn2O3 and NaOH solution. The morphological observation indicates that the obtained Na0.44MnO2 nanowires with diameters of about 20-30 nm, length up to several micrometers were formed by this process. The electrochemical properties of fabricated materials were investigated by means of cyclic voltammetry technique and show that Sodium Manganese Oxide (NaxMnO2) is a promising material in the field of research and fabrication alkaline ion battery

Structure elucidation off seven steroids from Sinularia conferta.

Seven steroids were isolated from the methanol extract of the soft corals Sinularia conferta. These steroids were elucidated as 7a-methoxyergosta-5,24(28)-diene-3b-ol (1), ergosta-5-ene-3β,7α-diol (2), 3β,7α-dihydroxyergosta-5,24(28)-diene (3), 3β-hydroxyergosta-5,24(28)-diene-7-one (4), ergosta-24(28)-ene-3β,5α,6β-triol-6-acetate (5), ergosta-24(28)-ene-3β,5α,6β-triol (6), and ergosta-3β,5α,6β-triol (7) by 1D and 2D-NMR experiments and comparison with reported data. Keywords. Sinularia conferta, Alcyoniidae, soft coral, steroid

Synthesis and Characterization of Silver Nanoplates by a Seed-mediated Method

Silver nanoplates (SNPs) having different size were synthesized by a seed-mediated method. The seeds -silver nanoparticles with 4 – 6 nm diameters were synthesized first by reducing silver nitrate with sodium borohydride in the present of Trisodium Citrate and Hydrogen peroxide. Then these seeds were developed by continue reducing Ag$^+$ ions with various amount of L-Ascorbic acid to form SNPs. Our analysis showed that the concentratrion of L-Ascorbic acid, a secondary reducing agent, played an important role to form SNPs. In addition, the size and in-plane dipole plasmon resonance wavelenght of silver nanoplates were increased when the concentration of added silver nitrate increased. The characterization of SNPs were studied by UV-Vis, FE-SEM, EDS and TEM methods

STUDY ON NITRIFICATION PROCESS BY AERATED SUBMERGED BIOFILTER (ASBF)

Joint Research on Environmental Science and Technology for the Eart

Investigating the Effect of Future Orientation on Saving Intention of Generation Z’s University Students in Vietnam’s Northern Region

Young people are often thought to have a lifestyle focusing on enjoyment, which is why issues related to saving among the youth, especially saving money, receive significant attention from society. This issue has been analyzed in some previous studies; however, there is a new factor that has not been explored in the context of Vietnam, which is future orientation. The purpose of this study is to find out the relationship between future orientation, attitude towards saving and saving intention of generation Z university students in Northern Vietnam. The research method used was the combination of qualitative and quantitative methods. The primary data was collected from 531 respondents who are currently studying at universities in Northern Vietnam and the data was analyzed by using SPSS and AMOS software. The structural equation modeling (SEM) method was used, and the results indicate that both future orientation and attitude towards saving have a positive impact on savings intention. Furthermore, the mediating role of attitude in the relationship between future orientation and saving intention was confirmed. Therefore, the results should be applied by governmental agencies, financial organizations and individuals, especially young people, to encourage saving intention, and furthermore, saving behavior