Science & Technology Asia

Forecast of Rooftop PV Adoption in Thailand

Aksornchan Chaianong, Athikom Bangviwat, Christoph Menke — Thu, 31 Oct 2019 00:00:00 +0700

As the interest in rooftop photovoltaic (PV) systems has increased in Thailand, it is necessary to evaluate issues on grid integration and policy impacts. This study establishes a systematic approach to forecasting annual PV adoption that is necessary to analyze PV impacts of future actions in Thailand. A “Customer-adoption Model” was selected to forecast PV adoption until 2036. The payback period is the main indicator for addressing total PV adoption in 2036 and the Bass diffusion model is used to address annual PV adoption for four customer groups (residential scale, small general service, medium general service, and large general service). The two main parameters, buyback rate and PV installation cost reduction, are included to forecast PV adoption for eight scenarios. Under the assumption of a two percent annual PV cost reduction and no buyback rate, Thailand’s solar PV goal can be achieved in 2025, instead of 2036. Also, in 2036, PV is expected to constitute about 9%–14% of the energy basis of the overall system. Thai utilities should not only focus on total PV adoption but also consider annual PV adoption, since utilities need to prepare their power systems and staffs before hosting PV every year.

Additional Growth of Dominant Follicle During Synchronized Ovulatory Cycle Affects Ovulatory Follicle Size, Corpus Luteum Parameters, and Progesterone Level in Northern Thai Native Cattle

Thu, 31 Oct 2019 16:08:57 +0700

The aim of this research was to evaluate the additional growth rate of dominant follicle (DF) using a pregnant mare’s serum gonadotropin (PMSG) in a 7-day progesterone (P₄)-gonadotropin releasing hormone (GnRH)-based program on follicular development and luteal function in White Lamphun cows. Cows in the PMSG-treated group (n=10) received PMSG on day of a P₄ device removal (on Day 7) in 7-day P₄-GnRH-based program, while cows in the PMSG-untreated group (n=10) did not receive PMSG treatment. Ultrasonography was used to scan ovaries to determine development of ovulatory follicle (OF) and formation of corpus luteum (CL). Blood samples were collected to examine P₄ concentration. The OF diameter and CL parameters (size, area, and volume) were greater in the PMSG-treated cows than in the PMSG-untreated cows (P < 0.05). Ten days after ovulation, the greatest P₄ concentration was found in the PMSG-treated group (P < 0.05). In conclusion, additional growth rate of DF using PMSG in 7-day P₄-GnRH-based program results in increase in OF development, CL parameters, and greater P₄ concentration in White Lamphun cows.

Heat Transfer of Hydromagnetic Convective Flow along a Semi-circular Enclosure Filled with Nanofluids using a Two-dimensional non-homogeneous Model

Sharmin Akter — Thu, 31 Oct 2019 15:36:50 +0700

In this paper, the problem of hydromagnetic convective flow along a semi-circular enclosure filled with nanofluids using a two-dimensional non-homogeneous model have been studied numerically. The circular wall of the enclosure is maintained at constant cold temperature whereas various combinations of the thermal boundary conditions at the bottom heated wall are considered. The enclosure is permeated by an inclined uniform magnetic field and the effects of gravity, Brownian motion and thermophoresis are incorporated into the nanofluid model. In the numerical simulation, here is considered water, kerosene as base fluids and Cobalt as nanoparticles. The Galerkin weighted residual finite element method has been employed to solve the governing partial differential equations after converting them into a non-dimensional form using a suitable transformation of variables. The effects of various parameters such as Hartmann number and Rayleigh number on isotherms have been displayed graphically for nanofluid. The heat transfer augmentation for various thermal boundary conditions has been done from the bottom heated wall for and nanofluid. The results show that the heat transfer rate can be decreased with the increasing values of the Hartmann number but it can be increased by increasing the Rayleigh number. The obtained numerical results also indicate that the variable thermal boundary conditions have significant effects on the flow and thermal fields. Finally, it is observed that the heat transfer rate is higher for nanofluid than for nanofluid.

Comparative Study on Biological Activities of Steamed and Non - Steamed Ginger Extracts

Thu, 31 Oct 2019 16:19:09 +0700

Ginger is used for treating motion sickness, nausea and vomiting. The traditional Thai method of preparation is to steam the rhizome before preparing the remedy. There is no report comparing the biological activity and quality of extracts from steamed and non-steamed rhizomes. The objective was to compare the anti-inflammatory activities, cytotoxicity and quality of steamed and non-steamed ginger extracts. All extracts were tested for their potential anti-inflammatory properties via the inhibitory effect on NO and PGE₂ production, and cytotoxic activity via sulforhodamine B assay. Loss on drying, total ash and acid - insoluble ash determinations were used as quantitation evaluation to standardize the ginger extracts. The results showed that the quality of all samples was within standard guidelines. The anti-inflammatory NO inhibition effect was higher in the steamed ginger ethanol extract (AZOE) than in the non-steamed ginger ethanol extract (HZOE), but lower than prednisolone as a positive control, with IC₅₀ values of 13.47 ± 0.20, 19.64 ± 0.33 and 1.33 ± 0.02 µg/ml, respectively. The effect of PGE₂ inhibition of AZOE, HZOE and positive control, had IC₅₀ values of 0.40 ± 0.06, 0.63 ± 0.02 and 0.066 ± 0.004 µg/ml, respectively. However, the steamed and non-steamed ginger ethanol extracts were not cytotoxic to either SKOV - 3 or HeLa cells. Steamed ginger had a higher inhibition effect on NO and PGE₂release than non - steamed ginger. These results support the traditional Thai method of steaming the rhizome before preparing the medicine.

Increase Stability of Soft Clay Embankment for Flood Prevention Using Compaction and Lining Techniques

Vannee Sooksatra, Pawinee Jinga — Thu, 31 Oct 2019 15:52:31 +0700

The purpose of this research is to study and compare the stabilities of soft clay embankments for flooding protection using soil compaction and soil lining techniques in construction. There are five types of soft clay embankments with three-meter height used in this research. The width at the top of the embankment is one meter and the vertical to horizontal ratio of slope of embankment on the water side equals 1:1. The soil compaction technique was used to construct the embankment types 1, 2 and 3 and the value of coefficient of permeability of clay in embankment to be 1x10^-5 cm./sec was given. The vertical to horizontal ratio of slope of embankments on the dry side equal 1:1, 1:1.5 and 1:2, respectively. The soil lining was used to construct the embankment types 4 and 5 and the vertical to horizontal ratio of slope of embankments on the dry side equals 1:1, without compaction techniques. Lining material with 0.10 meter thickness was placed on the water side surface of the embankment. The coefficient of permeability of lining material used in embankment types 4 and 5 equals 1x10^-5 cm/sec. and 1x10^-6 cm./sec., respectively. The research process consisted of using parameters obtained from shear strength test and water flow test through soft clay embankment simulated in laboratory to analyze water flow and slope stability analysis of the embankment. In addition, the area and budget for construction of embankment, not including the soil compaction and soil lining cost, were used to select the suitable type of soft clay embankment. The results showed that the soft clay embankment type 5, using soil lining on the water side surface of the embankment, was the most suitable embankment. Also, the level of stability of the soft clay embankment type 5 had the highest value with the need to use area and budget for construction less than embankment types 1, 2 and 3.

A Survey in Bacteriological Quality of Traditional Dried Seafood Products Distributed in Chon Buri, Thailand

Thu, 31 Oct 2019 16:25:47 +0700

This study aimed to assess physicochemical and bacteriological qualities of dried seafood products distributed in Chon Buri province, Thailand. Forty-four dried seafood samples were collected from local markets and examined for pH, water activity (a_w), salt content, numbers of viable bacteria and halophilic and halotolerant bacteria, numbers of Escherichia coli and Staphylococcus aureus and the presence of Salmonella, Vibrio parahaemolyticus and Vibrio cholerae using a standard protocol. Values of pH, a_wand salt content in dried seafood products were 5.16 ± 0.04 – 8.63 ± 0.03, 0.221 ± 0.01 – 0.822 ± 0.02 and 0.28 ± 0.03 – 18.92 ± 0.10%, respectively. Numbers of viable bacteria, and halophilic and halotolerant bacteria were 10² – 10⁹ and 10² – 10⁹ CFU g^-1, respectively. Main compositions of total viable bacteria, and halophilic and halotolerant bacteria in dried seafood products were Staphylococcus, Bacillus and Pantoae. Based on regulatory standards for cooked ready-to-eat and prepared seafood products set by the Department of Fisheries, Thailand, nineteen (43.18%) samples contained viable bacteria numbers exceeding the allowable limit. Two dried shrimp products (4.55%) harbored E. coli over a regulatory acceptable value of 10 MPN g^-1. All dried seafood products had S. aureus numbers within allowable limit for good quality of processed seafood products. None of Salmonella, V. parahaemolyticus and V. cholerae was isolated from all dried seafood products. This study indicates that consumption of cooked ready-to-eat and prepared dried seafood products may constitute a potential hazard of foodborne infection.

Investigation of Double Slope Solar Distillation Efficiency using Heat Absorber Made from Zinc

Thu, 31 Oct 2019 16:00:13 +0700

The productivity of water treatment through distillation method was studied by varying the size of the zinc heat absorber in a solar-based distillation unit. An additional zinc heat absorber was proposed to improve the efficiency of the distillation unit. This research investigates the usage of zinc heat absorber with size 10 to 90% of water surface area. The temperature at various locations inside the distillation unit was monitored throughout the operation in order to obtain data necessary for the equation engineering solver method, which was conducted to calculate the efficiency of the distillation system. It was found that the zinc heat absorber that is 10% of the water area produced 1.43 liters of condensed product per day providing efficiency of 25.99%. The efficiency reduced significantly to 15.02% when the size of the heat absorber was increased to 90%.

Effects and Chemical Contents of Hydrolysis Modification of Aqueous Roselle Extract to Reflect the Antioxidant and Anti-Inflammatory Effects

Varitha Ariyabukalakorn, Sumalee Panthong, Arunporn Itharat — Thu, 31 Oct 2019 16:32:28 +0700

Hibiscus sabdariffa (roselle) has been widely used in Thai traditional medicine and food products. However, roselle effects may be unstable under the acidic conditions in the stomach. Thus, the objective of this research was to investigate the stability of bioactivity of roselle extract under acidic conditions. Roselle aqueous extract and acid hydrolysis of roselle extract were assessed for content of phenolic compounds by using Folin-Ciocalteu’s colorimetric method, for antioxidant effect by DPPH radical scavenging assay, and for anti-inflammatory effect by using inhibition of nitric oxide production in RAW264.7 cell line. Five positive marker compounds in roselle extracts (chlorogenic acid, coumaric acid, ferulic acid, quercetin and cyanidin-3-o-sambubiosides) were determined by a modified HPLC method. The results showed that acid hydrolysis of roselle extract showed higher antioxidant activity with EC₅₀ of 14.12±0.92 µg/ml and anti-inflammatory with IC₅₀ of 16.84±3.18 µg/ml than the aqueous extract. Moreover, acid-hydrolyzed roselle extract showed higher total phenolic content than aqueous roselle extract. For HPLC analysis, the acid-hydrolyzed extract contained no chlorogenic acid and cyanidin-3-o-sambubiosides, but levels of the others were higher than for the aqueous extract. The results revealed roselle extract showed higher biological activity and active compounds content after acid hydrolysis.

Effects of Gibberellic Acid Applied at Different Flowering Stages on Agronomic Traits and Yields of Hybrid Rice Parental Lines

Sokornthea Pin, Tanee Sreewongchai, Damrongvudhi Onwimol — Thu, 31 Oct 2019 16:38:34 +0700

Gibberellic acid (GA₃) application in hybrid rice seed production plays a vital role in increasing seed yield; however, improper use of GA₃ may affect diversely the growth of hybrid parental lines. This study aimed to investigate the effects of GA₃ application at different flowering stages on agronomic traits and seed yield of hybrid parental lines. A micro-crossing plot experiment was employed for A line multiplication (HCS^A/HCS^B) under five treatments: applying GA₃ at 0%, 10%, 30% and 50% panicle heading stages and not applying GA₃. The results indicated flag leaf length, number of internodes, length of base internode, spikelets per panicle, total dry biomass of both lines, panicle length of HCS^A line and seed setting rate of HCS^Bline were not significantly different among the treatments. However, applying GA₃ at 10% panicle heading to 50% flowering stage significantly increased plant height, length of 1^st, 2^nd, and 3^rd upper internodes, total length of these three upper internodes and panicle exsertion rate of these lines. Interestingly, applying GA₃ at 30% panicle heading stage enhanced A line to produce significantly higher panicle exsertion, stigma exsertion, and seed setting rates, ultimately leading to the highest seed yield of A line, while applying GA₃at 0% panicle heading stage slightly reduced panicle exsertion rate, and produced lower seed yield of both parental lines. These results suggest that applying GA₃at 30% panicle heading stage can be an effective method for increasing seed yield of A line. A verification test is necessary to confirm the present results.

Evaluation of Hypertonic Saline-Sodium Hydroxide Method for Concentration of Sputum Samples for Mycobacterial Culture

Anugoon Bunkhong, Wijit Wonglumsom, Duangnate Pipatsatitpong — Thu, 31 Oct 2019 16:43:31 +0700

Mycobacterium tuberculosis complex (MTBC) is a major causative agent of public health problems. Nontuberculous mycobacteria are also increasingly encountered worldwide. Acid-fast bacilli (AFB) staining and culture are conventional methods used for mycobacterial identification. The aim of the study was to compare the performance of the two methods for AFB staining and culture, i.e. The hypertonic saline-sodium hydroxide (HS-SH) technique was compared with the N-acetyl-L-cysteine-sodium hydroxide (NALC-NaOH) method for AFB staining and cultivation. A cross-sectional study was conducted in a tuberculosis laboratory of the 3^rd Office of Disease Prevention and Control, Nakhon Sawan Province, Thailand, during October 2015 to September 2016. Totally, 427 paired samples of sputum were digested and decontaminated by HS-SH and NALC-NaOH methods. After concentration, the processed samples were cultured in Löwenstein–Jensen (LJ) media and Mycobacteria Growth Indicator Tube (MGITs). The direct smear detection before and after concentration of the sputum by both methods was also examined. To evaluate HS-SH method, sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), accuracy and kappa were analyzed. The positive rates of AFB smears by both concentration methods were significantly higher than the direct method (P=0.032). The HS-SH method was highly comparable to the traditional NALC-NaOH method for microscopy and culture in LJ media and MGITs (kappa=0.96, 0.59 and 0.45, respectively) with no statistically significant difference. Sensitivity, specificity, PPV, NPV and accuracy of the HS-SH method for cultivation was 96.3%, 100.0%, 100.0%, 94.5% and 97.7%, respectively. The conclusion, The HS-SH method demonstrated good sensitivity, specificity, PPV, NPV and accuracy similar to NALC-NaOH method for sputum digestion and concentration of both microscopy and culture with low cost and workload.

Fekete-Szegö Problem for Certain Classes of Analytic Functions Associated with Petal Type Domain and Modified Sigmoid Function

Sunday Oluwafemi Olatunji, Hemen Dutta — Mon, 04 Nov 2019 11:45:52 +0700

In this work, the authors studied the Fekete-Szegö problems for certain classes of analytic functions associated with petal type domain and modified sigmoid function. The initial coefficient bounds have been obtained and discussed the relevant connection to Fekete-Szegö inequalities. The results give birth to some corollaries.