155 research outputs found

    Effect of Storage Temperatures on Color of Tomato Fruit (Solanum Lycopersicum Mill.) Cultivated under Moderate Water Stress Treatment

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    AbstractModerate water stress tomato cultivated hydroponically in the greenhouse contains high lycopene and very sensitive to storage temperatures. This study aimed to observe the effect of storage temperatures on the lycopene content and color quality parameters of tomato (both moderate water stress and no water stress tomato). The lycopene content of water stress tomato increased with the temperatures higher than 10°C while no water stress tomato relatively stable or increased slightly. The lightness (L*) value of water stress and no water stress tomato decreased during storage in 10, 15, 25 and 30°C temperatures. The redness (a*), yellowness (b*), a*/b*, hue (h), and chroma (C*) remained stable after 4 days storage in those temperatures. Storage with temperatures above 15°C increased the color parameters value of both water stress and no water stress tomato. Moderate water stress treatment increased the redness color and harvesting tomato in ripening stage will only shows lightness (L*) major change during storage

    XBee wireless sensor networks for heart rate monitoring in sport training

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    Heart Rate Monitors (HRMs) have become widely used since the last two decades. It used as training aid for various types of sports. And the development of new HRMs has evolved rapidly. Thus, in order to determine the exercise intensity of training session or race, HRMs are mainly used. Compared to the other indication of exercise intensity, Heart rate is easy to monitor, compatible to use in most situation and relatively cheap. Thus, it is most beneficial if wireless sensor network can be implementing into the system. Other than monitored their condition by themselves, this system may allowed a number of athletes being monitored simultaneously. Arduino-Nano board was used to interface with nRF24AP1 and XBee. The wireless sensor network consists of a microcontroller on Arduino-Nano board, nRF24AP1 and the XBee wireless communication module which is based on the IEEE 802.15.4. This system will involve peer to peer communication of ANT+ and mesh networking among the XBee

    Tingkat Serangan Larva Spodoptera frugiperda (Lepidoptera: Noctuidae) pada Tanaman Jagung di Ketinggian Tempat yang Berbeda

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    Apriyana E, Syaputra H, Sardilla K, Nasution NA, Nofetra T, Rahmawati T, Irsan C. 2021. Tingkat Serangan Larva Spodoptera frugiperda (Lepidoptera: Noctuidae) pada Tanaman Jagung di Ketinggian Tempat yang Berbeda. In: Herlinda S et al. (Eds.), Prosiding Seminar Nasional Lahan Suboptimal ke-9 Tahun 2021, Palembang 20 Oktober 2021. pp. 563-569.  Palembang: Penerbit & Percetakan Universitas Sriwijaya (UNSRI). Corn (Zea mays L.) is a commodity that is widely cultivated in Indonesia. Cultivation is carried out in various areas, from the lowlands to the highlands. Cultivation of corn plants is inseparable from pest attacks, one of which is Spodoptera frugiperda (Lepidoptera: Noctuidae). The altitude of the place is not known with certainty with the influence of S. frugiperda attack. In terms of knowing the attack rate of S. frugiperda on corn was done by collecting data. Aim to find out how the effect of altitude on the level of attack S. frugiperda. From the results of the literature study showed that at altitude 1000 masl, the attack was categorized as high with a certain temperature range. The attack rate of S. frugiperda was also known to be influenced by climate and the presence of natural enemies in the ecosystem. So, it can be concluded that altitude didn't absolutely affect the attack of S. frugiperda on maize

    Solvent dependence of the rheological properties in hydrogel magnetorheological plastomer

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    Chemically crosslinked hydrogel magnetorheological (MR) plastomer (MRP) embedded with carbonyl iron particles (CIPs) exhibits excellent magnetic performance (MR effect) in the presence of external stimuli especially magnetic field. However, oxidation and desiccation in hydrogel MRP due to a large amount of water content as a dispersing phase would limit its usage for long‐term applications, especially in industrial engineering. In this study, different solvents such as dimethyl sulfoxide (DMSO) are also used to prepare polyvinyl alcohol (PVA) hydrogel MRP. Thus, to understand the dynamic viscoelastic properties of hydrogel MRP, three different samples with different solvents: water, DMSO, and their binary mixtures (DMSO/water) were prepared and systematically carried out using the oscillatory shear. The outcomes demonstrate that the PVA hydrogel MRP prepared from precursor gel with water shows the highest MR effect of 15,544% among the PVA hydrogel MRPs. However, the samples exhibit less stability and tend to oxidise after a month. Meanwhile, the samples with binary mixtures (DMSO/water) show an acceptable MR effect of 11,024% with good stability and no CIPs oxidation. Otherwise, the sample with DMSO has the lowest MR effect of 7049% and less stable compared to the binary solvent samples. This confirms that the utilisation of DMSO as a new solvent affects the rheological properties and stability of the samples

    Fluvial processes in compound straight channels: a laboratory investigation

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    Floods are become frequent occurrence in every part of the world. The field of flood hydraulics has been keenly studied to enhance the understanding on its processes and impacts to the environment. The main impacts of frequent floods incidents are soil erosion phenomenon which leads to sedimentation problems in the drainage and river systems. It is extremely important to understand the sedimentation process and the flow behaviour patterns in the water course for post-flood events. Experimental investigations on the overbank flow in mobile bed straight channels have been undertaken. Significant changes on the bed morphology due to the changes in flow behaviour are studied. The findings on roughness coefficient, lateral distribution of stream-wise velocity, secondary currents, bed shear stress and bed formation are presented in this paper. Results show that the resistance coefficient increased with flow depth in the channel and the increments are about 32% and 42% for floodplain and main channel sections respectively

    Estimation of turbidity in water treatment plant using hammerstein-wiener and neural network technique

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    Turbidity is a measure of water quality. Excessive turbidity poses a threat to health and causes pollution. Most of the available mathematical models of water treatment plants do not capture turbidity. A reliable model is essential for effective removal of turbidity in the water treatment plant. This paper presents a comparison of Hammerstein Wiener and neural network technique for estimating of turbidity in water treatment plant. The models were validated using an experimental data from Tamburawa water treatment plant in Kano, Nigeria. Simulation results demonstrated that the neural network model outperformed the Hammerstein-Wiener model in estimating the turbidity. The neural network model may serve as a valuable tool for predicting the turbidity in the plant

    In vitro antiproliferative and antioxidant activities of the extracts of Muntingia calabura leaves.

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    The in vitro antiproliferative and antioxidant activities of the aqueous, chloroform and methanol extracts of Muntingia calabura leaves were determined in the present study. Assessed using the 3,(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) (MTT) assay, the aqueous and methanol extracts of M. calabura inhibited the proliferation of MCF-7, HeLa, HT-29, HL-60 and K-562 cancer cells while the chloroform extract only inhibited the proliferation of MCF-7, HeLa, HL-60 and K-562 cancer cells. Interestingly, all extracts of M. calabura, which failed to inhibit the MDA-MB-231 cells proliferation, did not inhibit the proliferation of 3T3 (normal) cells, indicating its safety. All extracts (20, 100 and 500 μg/ml) were found to possess antioxidant activity when tested using the DPPH radical scavenging and superoxide scavenging assays with the methanol, followed by the aqueous and chloroform, extract exhibiting the highest antioxidant activity in both assays. The total phenolic content for the aqueous, methanol and chloroform extracts were 2970.4 ± 6.6, 1279.9 ± 6.1 and 2978.1 ± 4.3 mg/100 g gallic acid, respectively. In conclusion, the M. calabura leaves possess potential antiproliferative and antioxidant activities that could be attributed to its high content of phenolic compounds, and thus, needs to be further explored

    Physicochemical properties of powdered protein hydrolysate from yellowstripe scad (Selaroides leptolepis) fish

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    Yellowstripe scad fish (YSF) or Selaroides leptolepis belongs to the small pelagic group that is abundantly found in South China Sea and is categorised as low value fishes. This study is designed to explore the physicochemical properties of YSF protein hydrolysate extracted using sodium phosphate buffer followed by 0.5%-2.0% of Alcalase at a series of hydrolysis time (1 hr and 2 hr). The properties of freeze and spray dried protein hydrolysate were evaluated for yield, degree of hydrolysis, protein content, microstructure and water holding capacity. Results showed that prolonged hydrolysis time exhibited increasing yield (0.6%-1.6% for spray drying and 12-16% for freeze drying) and high degree of hydrolysis (80-95%). Protein content recovered from hydrolysis process is within 20-29%. Microstructure of freeze dried YSF protein hydrolysate had 'collapsed-building' structure (irregular shapes with edges) while spray dried had small and spherical structure. Freeze dried protein hydrolysates were significantly (p < 0.05) higher than spray dried hydrolysates in water holding capacity

    Rheological properties of carbon nanotubes-reinforced magnetorheological elastomer

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    Magnetorheological elastomer (MRE) based on the natural rubber with different types of multiwall carbon nanotubes (MWCNT) as additives were synthesized. MRE with pristine MWCNTs was prepared as a control and the carboxylated (MWCNT-COOH), as well as hydroxylated (MWCNT-OH) were introduced as new additives in MRE. Their rheological properties under different magnetic field were evaluated by using the rheometer (MCR 302, AntonPaar, Austria) equipped with the electromagnetic device. The dependency of MREs towards excitation frequencies under different magnetic field was investigated. It is shown that the storage modulus and loss factor of MRE with functionalized MWCNTs exhibited noticeable increment in MR performance compared to control parallel with the frequencies increment

    Current practice of early leak detection methods for underground storage tanks

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    This article aims to provide general review on current practice of leak detection methods of underground storage tanks (UST). Fuel (i.e. gasoline and diesel oil) leakage from UST can contaminate groundwater and drinking water with various hydrocarbon contaminants. These leaks create ponds of fuel that spill into the land and aquifers, polluting and seriously destroying habitats. Numerous efforts have been focused on the development of leak detection to the tanks. However, without the opportunity to conduct fault intensity calibration and estimate a product's lifetime, there is a lack of information provided to consider the condition of previous underlying leakage. As a result, it is too late whether the harm has already been done. There are methods of detection that have been studied for the past ten years. Many approaches have been practised to detect leakage. Specific sensing devices will combine with additional applications that analyse and interpret the data to detect storage tank leaks. Various methods will provide different results depending on the feature chosen. Some approaches will use machine learning to analyse the provided data and provide the best leak detection result. This paper will explore the best leak detection techniques to improve underground tanks' structural integrity. At the end, this paper will give some overview on current practice early detection methods on underground storage tanks for future research
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