ISSN: 0125-2364, Online ISSN: 2586-9531

Volume 44 No.2 April - June 2016


P.237-248

PDF

Enhancing thermoelectric performance of BiCuSeO

การเพิ่มประสิทธิภาพทางเทอร์โมอิเล็กทริกของวัสดุ BiCuSeO

ศุภกฤต วงษ์ประการ และ สุปรีดิ์ พินิจสุนทร*

Thermoelectric materials are very interesting because they can directly convert thermal energy into electrical current. In this article, we have discussed one of thermoelectric oxide materials, i.e. BiCuSeO. This material has received a number of interests because of its stability at high temperature and the high efficiency in converting heat to electricity. This article has collected several research works related to this material including crystal structure, thermoelectric properties, and synthesis methods. The main focus is on improving thermoelectric properties of BiCuSeO. Several approaches have been attempted, for instance, doping Pb2+ or other elements in the BiCuSeO structure for enhancing phonon scattering, or increasing Cu vacancies in the BiCuSeO structure for creating more holes. The authors have compared the differences in each approach for enhancing thermoelectric properties. We have also, in the end, made suggestions for improving the thermoelectric efficiency of BiCuSeO.


P.249-261

PDF

Fracture in Ceramic Materials and their Toughening

การแตกหักและกลไกการเพิ่มความเหนียวของวัสดุเซรามิก

ธวัช ชนะดี

This review article presented an understanding of brittle ceramic materials. The main topics including typical properties, fracture mechanic and toughening of ceramic materials were proposed. Toughening arose from the ability of materials to absorb energy and plastically deform before being fractured by different mechanisms such as crack deflection, transformation toughening, microcracking and fiber pull-out through particulate or fiber reinforcement in ceramic matrix. This information can be used for guiding the processing design to increase the strength of ceramic materials.


P.262-271

PDF

A Technique of the Easy Axis Distribution Measurement in Perpendicular Recording Media Part I

เทคนิคการวัดการกระจายตัวของทิศแกนง่ายสำหรับแผ่นบันทึกข้อมูล แบบตั้งฉาก ตอนที่ 1

เจษฎา จุรีมาศ

This paper is to purpose the technique for the measurement of the easy axis distribution of perpendicular recording media (PRM) which is capable of supporting a high areal densitiy of 1 Tbit/in2. The several techniques which have been investigated the distribution can be separated into 2 methods by the crystallography texture using X-ray rocking curve and the magnetic measurement. The important factors affecting the easy axis distribution are exchange interactions and magnetostatic which are not evident in the variation of crystalline technique. Hence, the magnetic measurement is preferred for the measurement of easy axis distribution. In the past, the traditional remanence method used to measure the distribution for longitudinal recording media has been applied for PRM. But this method cannot be used due to the effect of large demagnetising field which is the most difficult to correct. Therefore, the variation of coercivity technique has been purposed to measure the easy axis distribution. The advantage of this technique is that the large demagnetising field is zero at the coercivity.


P.272-281

PDF

Cytotoxicity of Gluconasturtiin and Its Derivative against MCF-7 and HepG2

ความเป็นพิษของกลูโคนาสเตอติอินและสารอนุพันธุ์ ต่อเซลล์ MCF-7 และ HepG2

Nattaya Konsue* and Ahmad Faizal Abdull Razis

The putative anticancer abilities of isothiocyanates, bioactive compounds in brassica vegetables, have been widely published. In the current study, gluconasturtiin, found naturally in watercress, and its derivative, phenethyl isothiocyanates (PEITC), toxicity against human breast cancer cells MCF-7 and hepatoma cell line HepG2 were determined employing MTT assay. A range of concentrations between 0-100 μM was used to study dose dependent cytotoxicity at 24, 48 and 72 hrs incubation periods. Paclitaxel at the same concentrations was served as a positive control. The results showed that in MCF-7 cell line, PEITC led to a time-dependent decrease in cancer cells viability with IC50 of 10.22, 3.61 and 2.68 μM at 24, 48 and 72 hrs, respectively, whereas those of HepG2 were 6.74, 4.22 and 4.19 μM. Moreover, gluconasturtiin had no effect on both cell lines at the concentration range studied. Apoptogenic effects of PEITC on MCF-7 were studied using fluorescence microscopy (AO/PI double staining). When cells were exposed to PEITC for 48 hrs at IC50 dose chromatin condensation and nuclear fragmentation were noticed. Moreover, apoptosis is one of chemopreventive mechanisms of PEITC which, however, toxicity on normal cells should be further investigated.


P.282-293

PDF

The Gastroprotective Effects of the Ethanolic Extraction from Musa (ABB group) ‘Kluai Nam Wa’ Flower in Wistar Rats

การป้องกันการเกิดแผลในกระเพาะอาหารจากสารสกัดหัวปลีกล้วยน้ำว้า (Musa (ABB group) ‘Kluai Nam Wa’) ด้วยแอลกอฮอล์ ในหนูวิสตาร์

Pattrawan Khamboonruang   Thiraporn Anuntasethakul*   Somphop Navephap And Supang Maneesri LeGrand

The flower of Musa spp. has interested the scientific community due to its numerous pharmacological properties and potential therapeutic applications. The present study aimed to investigate the gastroprotective effects of the ethanolic extraction from Musa (ABB group) ‘Kluai Nam Wa’ flower (EF) on experimental models against gastric ulcer induced by absolute alcohol, indomethacin and swimming stress in Wistar rats. The EF was orally administered at dosages of 250, 500 and 1,000 mg/kg for 1 h prior to induction of gastric ulcer. The common parameters determined were ulcer index (UI), protection percentage (% protection), gastric secretion and gastric wall mucus content. The results demonstrated that pre-treatment with EF at doses of 250, 500 and 1,000 mg/kg showed a potent ulcerprotective effect in a dose-dependent manner which significantly (p<0.05) reduced ulcer index at the lowest dose (250 mg/kg) in all models as compared to the control group. Pre-treatment with EF at a dose of 1,000 mg/kg showed potential gastroprotection 78.80%, 70.26% and 68.73% in absolute alcohol, swimming stress, and indomethacin models respectively. The gastroprotective activity of EF involved an anti-secretory effect as it significantly (p<0.05) decreased gastric acidity and pepsin without any effect on gastric volume and total proteins when compared to the control group. Pre-treatment with EF promoted gastroprotective effect by significantly (p<0.05) increasing gastric wall mucus content and gastric pH when compared to the control group. The results suggest that EF presents anti-ulcer activities against absolute alcohol, indomethacin and swimming stress in Wistar rats. The gastroprotective activity of EF could involve promoting mucus secretion.


P.294-306

PDF

Tissue Culture of Curcuma pierreana Gagnep. for Conservation of Rare Plant in Thailand

การเพาะเลี้ยงเนื้อเยื่อมหาอุดมแดง (Curcuma pierreana Gagnep.) เพื่อการอนุรักษ์พืชหายากในประเทศไทย

เบญจพร ภูกาบหิน   สุรพล แสนสุข และ ปิยะพร แสนสุข*

Curcuma pierreana Gagnep. is a highly valued ornamental plant. A protocol has been developed for tissue culture of C. pierreana Gagnep., a rare plant from Thailand. Young shoots of C. pierreana Gagnep. (1 cm in length) were cultured on Murashige and Skoog (MS) (1962) medium containing 0, 0.1, 0.5, 1, 2, 4, 8 and 16 mg/l of cytokinin hormone alone (BA, Kinetin and TDZ), or a combination of cytokinins (BA and TDZ) and 0, 0.1, 0.5, 1, 1.5 and 2 mg/l of auxins (IAA, IBA and NAA) for eight weeks. The maximum average number of shoots (4.20 shoots/explant) was observed on the medium with the addition of 4 mg/l BA combined with 2 mg/l TDZ.The young shoots of C.pierreana Gagnep.cultured on the medium supplemented with 2 mg/l IAA produced the maximum average number of roots (25.71 roots/explant).


P.307-317

PDF

Antagonistic Effect of Coprophilous Fungi Against Colletotrichum sp. ST01 Causing Chili Anthracnose Disease

การเป็นปฏิปักษ์ของเชื้อราจากมูลสัตว์ต่อเชื้อรา Colletotrichum sp. ST01 สาเหตุโรคแอนแทรคโนสในพริก

สันทนา ขวัญมณี   สุทิน พรหมพงษ์   อัจฉรา เพิ่ม และ เสาวนิตย์ ชอบบุญ*

Chili is one of an important economic crop of Thailand. Currently, chili is facing a problem of lower production caused by anthracnose disease from fungal pathogen, Colletotrichum spp. Most farmers use chemicals to control anthracnose in chili which directly affect environment and farmer’s health. The objective of this study was to evaluate for their antagonistic activities of coprophilous fungi against Colletotrichum sp. ST01 by dual culture technique on potato dextrose agar. Five of seventeen isolates (ST10, ST19, ST14, ST18, and ST16) showed high antagonistic activity of > 60% against Colletotrichum sp. ST01. The inhibition percentage of Trichoderma sp. TS10, Trichoderma sp. ST19, Aspergillus sp. ST14, Apergillus sp. ST18, and Ceratocystis sp. ST16 was 100.00±0.00, 100.00±0.00, 68.70±3.68, 67.87±2.38, and 63.70±3.60, respectively. Coprophilous fungi showed the potential to inhibit Colletotrichum sp. ST01 in laboratory level. It is possible that these fungi could be applied for controlling anthracnose disease in chili.


P.318-330

PDF

Isolation and Determination of Antimicrobial Activity of Lactic Acid Bacteria from Fermented Fish Product, Pla-Som

การคัดแยกและการตรวจสอบความสามารถในการยับยั้งจุลินทรีย์ของ แบคทีเรียกรดแลคติกที่แยกได้จากผลิตภัณฑ์ปลาหมัก ปลาส้ม

Piyorot Hongsachart

Isolation of lactic acid bacteria (LAB) from Pla-Som samples collected from local markets in the area of Nong Khai province found a total of 37 LAB isolates including 8 cocci and 29 rods. Isolated LAB were subsequently determined antibacterial activities against 11 pathogenic bacteria using the disc diffusion method. It was found that the LAB isolate namely, L8-16 was effective against both Gram-negative and Gram-positive bacteria. It exhibited strong inhibition activity against Shigella sp., Pseudomonas sp. P. aeruginosa and moderate inhibition activity against Bacillus megaterium, Bacillus cereus, Escherichia coli and Salmonella Typhi. In addition, the isolate L7-1 also showed strong inhibition activity against S. Typhi and P. aeruginosa and moderate inhibition activity against Staphylococcus aureus, B. subtilis, E. coli and Klebsiella pneumoniae. Overall, the most of LAB isolates inhibited Gram negative bacteria more than Gram-positive bacteria with moderate (11-12 mm) and strong (13-15 mm) inhibition zones. There was only isolate L8-14 showed strong inhibition against B. cereus. Based on these results, isolated LAB would be considered to be potential biopreservatives in Pla-Som fermentation.


P.331-344

PDF

Genetic Diversity of Giant Freshwater Prawn (Macrobrachium rosenbergiide Man) on Farm in Kalasin Province Using RAPD-PCR Technique

ความหลากหลายทางพันธุกรรมของกุ้งก้ามกรามในบ่อเลี้ยงของเกษตรกร จังหวัดกาฬสินธุ์ โดยใช้เทคนิคอาร์เอพีดี-พีซีอาร์

กีรวิชญ์ เพชรจุล* และ มณีรัตน์ ศิริสวัสดิ์

The objective of this research was to investigate genetic diversity of giant freshwater prawn (Macrobrachium rosenbergii de Man) on farm in Kalasin province using RAPD-PCR technique. M. rosenbergii was found 3 characteristics such as: giant freshwater prawn blue claws (MrB), giant freshwater prawn gold claws (MrG) and giant freshwater prawn dwarfism (MrJ). Genomic DNA was extracted from the muscle of each individual of specimens with phenol: chloroform proteinase K method and screened appropriate oligonucleotide primers for amplification using 8 oligonucleotide primers, 10-12 base nucleotide length. The results showed that primer OPA03 and OPA07A were able to amplify the DNA in RAPD-PCR reaction. For RAPDPCR of these 2 primers of all M. rosenbergii showed 41 bands within sizes of 250-2000 bp. DNA fingerprints showed 29 polymorphic bands (70.73%) and 12 monomorphic bands (29.27%). The UPGMA dendrogram of RAPD-PCR pattern, constructed using NTSYSpc version 2.11x gave 2 groups of genetic relationships. Group 1 composed of (M. lanchesteri de Man) which separated clearly from group 2. Group 2 consisted of all M. rosenbergii (MrB, MrG and MrJ) which can be divided into 2 subgroups: subgroup 1 was only giant freshwater prawn dwarfism (MrJ) and subgroup 2 consisted of giant freshwater prawn blue claws (MrB) and giant freshwater prawn gold claws (MrG). The similarity coefficient between 2 groups and subgroups of group 2 exhibited approximately 52.00 and 67.50 percentages, respectively. This study showed different genetic diversity of M. rosenbergii farmed in Kalasin province. This information will benefit screening, breeding, conservation and broodstock management for desirable trait of commercial giant freshwater prawn in near future.


P.345-354

PDF

Formulation Development of Milk Pudding Substituted with Corn Milk

การพัฒนาสูตรพุดดิ้งนมสดที่ทดแทนด้วยน้ำนมข้าวโพด

ฤทัย เรืองธรรมสิงห์*   พรทิพย์ ปิยะสุวรรณยิ่ง และ น้องนุช ศิริวงศ์

The objective of this study was to develop pudding formula by substitution of corn milk for cow milk. The selected standard formula consisted of 36.5% milk, 14% sugar, 1.3% gelatin, 36.5% whipping cream, 11.6% egg york and 0.1% vanilla extract. The cow milk was substituted with corn milk at the level of 0 (control), 75 and 100%. The pudding formula with 100% corn milk substitution for cow milk and whipping cream (WC) was studied for comparison. The result showed that the most acceptable pudding was prepared from the formula with 100% corn milk replacement. Physical properties of the obtained pudding including L*, a*, b*, rupture strength and gel brittleness were 85.78, 4.30, 30.43, 105.47 g force and 9.94 mm, respectively. Nutritional values of the pudding with 100% corn milk could be comparable to those of the control whereas the percentage of calorie, carbohydrate and fat of the WC pudding decreased to 60.17, 36.49 and 73.80, respectively.


P.355-368

PDF

Optical Emission Spectroscopy of Zinc Acetate Vapor Discharge under the Shower Plasma Source

การวิเคราะห์สเปกตรัมทางแสงจากการแตกตัวของไอซิงค์อะซิเตต ภายใต้หัวกำเนิดพลาสมาแบบฝักบัว

อุกฤษฏ์ ฤทธิหงส์   อาทิตย์ ฉิ่งสูงเนิน* และ ปรเมษฐ์ จันทร์เพ็ง

In this research, the emission spectra from the shower plasma source were analyzed using the optical emission spectroscopy method. The zinc acetate vapor as a precursor together with helium and argon as carrier gases were discharged using the plasma enhanced-metal organic chemical vapor deposition (PE-MOVCD) technique at the working pressure of 800 Pa. After identifying the emission spectra from He/Zn(CH3COO)2 plasma, we found the maximum intensity of Zn I (411.32 nm) that corresponding to the rf power of 30 W and the rf bias of 10 W. This result indicates that the above conditions appropriate for dissociation of zinc atom from Zn(CH3COO)2 molecule. While the emission spectra from Ar/Zn(CH3COO)2 plasma shows the highest intensity of Zn I (472.21 nm) when using the rf bias of 10 W. The increasing of the rf bias power result to the increasing of Ar I (750.38 nm) emission line. This result indicates that there is higher argon discharge in the plasma after glow region corresponding to higher argon ion bombardment at the substrate during the formation of ZnO film. The ion bombardment arising from plasma-enhanced chemical vapor deposition is an attractive process for film growth due to its lower substrate temperature requirement. Therefore this technique is useful for deposition on thermally unstable materials.


P.369-383

PDF

New Fast Neutron Shielding Material Composing of Alternating Layers of Natural Rubber, SBR and Boron Oxide (B2O3) and Layers of Natural Rubber and Iron(III) Oxide (Fe2O3)

วัสดุกำบังนิวตรอนเร็วแบบใหม่ที่ประกอบด้วยวัสดุหลายชั้นของยางพารา ยางสังเคราะห์เอสบีอาร์และโบรอนออกไซด์ (B2O3) และชั้นของยางพาราและเหล็กออกไซด์ (Fe2O3)

ชญานิษฐ์ จำปี และ ดุลยพงศ์ วงศ์แสวง*

Neutrons have been widely used in many applications. Since neutrons have no electric charge, they can travel through electron cloud and directly interact with the atomic nucleus. Exposure to free neutrons can be hazardous especially fast neutrons from neutron source. Therefore, using neutron shielding material is very important. Optimized flexible and lightweight neutron shielding materials were designed using the Monte Carlo N-Particle (MCNP) code. Thicknesses of 10 cm were tested for neutron shielding performances. Simulation results indicated that the shielding material with four alternating layers of NR with 100 phr iron (III) oxide (Fe2O3) and of NR and SBR blend (1:1) with 5 phr boron oxide (B2O3) were most suitable for fast neutron shielding. The neutron shielding material of a spherical shape exhibits the best performance (43% neutron attenuation) compared with cuboid and cylindrical shapes. The optimum neutron shielding material design was fabricated and good homogeneity of the material was verified by neutron radiography. Therefore, this neutron shielding material can be utilized in neutron source applications.


P.384-397

PDF

Enhanced Efficiency of Intrusion Detection Systems with Honey Pot in Cyber Security

การเพิ่มประสิทธิภาพระบบตรวจจับการบุกรุกในการรักษาความมั่นคง ทางไซเบอร์ด้วยฮันนี่พอท

อรรถพล ป้อมสถิตย์

This paper presents how Honeypot can help enhancing the efficiency of the Intrusion Detection Systems (IDS) in cyber security. Honeypot will distract, delay, or deviate hackers from attacking the computer network. There are three attacking technique which cause Denial of Service (DOS), delay or deviate: TCP Flood, UDP Flood and ICMP Flood. Honeyd, a part of Honeypot will be used to create a virtual computer or a virtual server within a particular secured network, without firewall or any other forms of security. Only Honeypot will be deployed on the network, while the Snort program will be used on IDS. All programs will be developed as Open Source on Linux OS. As a result of test on the internal and external network attack, we found that we can enhance the efficiency of the Intrusion Detection Systems (IDS) in cyber security by using Honeypot. The attacked rates on LAN network and WLAN network were not much different. However, comparing TCP Flood attack and ICMP Flood attack, TCP Floods attacked rate was 33.75% higher on internal network and 53.47% higher on external network than ICMP Flood attacked rate. In conclusion, TCP Flood attack and all forms of internal attacks are most harmful in cyber security.


P.398-407

PDF

Natural Convection in a Porous Square Enclosure Containing an Oval-Shaped Heat Source

การพาความร้อนแบบธรรมชาติในโดเมนปิดรูปสี่เหลี่ยมพรุน ที่บรรจุแหล่งความร้อนทรงรี

ภัทรพร คำมุงคุณ และ สุพจน์ ไวท์ยางกูร*

In this paper, we present the numerical study of natural convection in a porous square enclosure containing an oval-shaped heat source. The finite element method is used to solve this problem. The fluid properties are laminar, viscous and incompressible flow, for steady state in a porous square enclosure containing an oval-shaped heat source. The boundary conditions of the side walls for the square enclosure are cold while the oval-shaped is heated. The Darcymodified Rayleigh number is between 10 and 103 . The problems studied are the behavior and distribution of isotherms, streamlines and heatlines when the value of Darcy-modified Rayleigh number and the size of the heat source are different.


P.408-417

PDF

A Comparative Gain in Areas under ROC Curve and Power of Tests Between Cumulative Logit GLMMs and Cumulative Probit GLMMs

ผลลัพธ์เชิงเปรียบเทียบด้วยพื้นที่ใต้โค้ง ROC และกำลังการทดสอบระหว่าง ตัวแบบผสมเชิงเส้นนัยทั่วไปแบบลอจิตสะสมและแบบโพรบิตสะสม

วีรานันท์ พงศาภักดี

Generalized Linear Models (GLMs) extend ordinary general linear model with fixed effects in the linear predictor by allowing non-normal responses and a link function of the mean. The Generalized Linear Mixed Models (GLMMs) are further extensions of GLMs that permits both the fixed effect and the random effect in models and account for the dependency inherent in data. However, limitation of few applications was found due to the complexity of the models and their efficiency. In this article, a further comparative gain in area under ROC curves and power of tests between the cumulative logit GLMMs and the cumulative probit GLMMs are investigated and discussed. The 1,000 empirical datasets for each condition of parameters and the number of clusters and cluster sizes are simulated using SAS rewritten macro program. The results reveal that the cumulative logit GLMM is superior (0.8%) to the cumulative probit GLMM. As the number of clusters and the cluster sizes are increased, the sensitivity and the precision through the AUC and power of the tests are better fitted. Overall, the maximum absolute percentage gain power between the two models is approximately 10% with satisfactorily high area under ROC curve values. It is clear that, for small and moderate intra-cluster correlation, the cumulative logit GLMMs are also preferred; otherwise, for more complicated cases; even if the two GLMMs are less efficiency than that before but still are closely adequate of fits significantly at 0.05. Hence the two GLMMs probably are used for further implementation in real data.