bluuebunny/crossref_metadata_2025 huggingface dataset:
Realizing topological corner states in two-dimensional Su-Schrieffer-Heeger model with next-nearest neighbor couplings
Authors: Ivanova P A , Olekhno N A , Kachin V I , Zhirihin D V , Seregin P S , Gorlach M A
Published: December 2020

In the present work, we consider a two-dimensional Su-Schrieffer-Heeger model with alternating positive tunneling couplings between the neighboring sites. We show that introducing next-nearest neighbor couplings results in the emergence of topological corner states for some values of the corresponding tunneling coupling. Our work resolves the contradiction that arose when such corner states absent in the original two-dimensional Su-Schrieffer-Heeger model were observed experimentally in its photonic realization based on the array of cylindrical microwave resonators.
Electronic transport features of MoTe2 caused by quenching
Authors: Marchenkov V V , Domozhirova A N , Naumov S V , Podgornykh S M , Chistyakov V V , Korenistov P S , Huang J C A
Published: December 2020

The electro- and magnetoresistivity of MoTe2 single crystals before and after quenching were measured at temperatures from 1.8 to 300 K and in magnetic fields of up to 9 T. It was demonstrated that quenching can lead to strong changes in values of the electro-and magneresistivity studied as well as in their temperature and field dependences. The peculiarities of these electronic transport characteristics changes were studied in detail.
Size effect in the kinetic properties in “sized” films of Bi2Se3 topological insulator
Authors: Chistyakov V V , Domozhirova A N , Huang J C A , Marchenkov V V
Published: December 2020

The Hall resistivity and magnetoresistivity of topological insulator Bi2Se3 thin films with a thickness from 30 nm to 75 nm in the temperature range from 4.2 to 80 K and magnetic fields of up to 10 T were measured. A size effect in the kinetic properties of bismuth selenide films was studied, i.e. a dependence of the Hall coefficient and magnetoconductivity of film dimensions. It was suggested that a similar size effect should be observed in other kinetic electronic properties, both of topological insulators and topological semimetals.
Simulation of induction chemical-thermal treatment of titanium disks in a massive refractory container
Authors: Voyko A , Fomina M
Published: December 2020

The results of numerical simulation of chemical-thermal treatment, namely, heating of a massive metal container with a working medium and a small-sized titanium disk sample, are presented. To study the heating kinetics of this system, the effect of the parameters of chemical-thermal treatment, in particular the inductor current from 3.4 to 8 kA at a frequency of 90 kHz, was determined.
Choosing the electrode material for the fast electrochemical actuator
Authors: Shlepakov P S , Uvarov I V , Naumov V V , Svetovoy V B
Published: December 2020

Electrochemical actuators are promising candidates for implementation in various microfluidic systems, but they suffer from a very long response time due to slow gas recombination. Water electrolysis performed by short voltage pulses of alternating polarity (AP) reduces the response time by several orders of magnitude. This process, however, results in a fast degradation of electrodes. It is important to find a material, which is able to withstand the AP operation without significant degradation. In this work the electrodes made of six metals are fabricated and tested. The current flowing through the cell, the threshold voltage for the explosive operation, and the wear of the electrodes are analyzed and compared.
Rotator for electromagnetic emission based on conformal mapping
Authors: Pesnyakov V , Vozianova A , Khodzitsky M.
Published: December 2020

Using conformal mapping it is proposed a device, which demonstrates the illusion effect. Emission from the current sheet source placed on the X-axis centered at the origin is almost fully rotated at an angle of 90 degrees. As a result, the observer would detect that the current sheet source placed on Y-axis.
Creation and study of liquid nanojunction using SPM-base technology
Authors: Zhukov M V , Lukashenko S Yu , Sapozhnikov I D , Golubok A O
Published: December 2020

The ion conductivity of the meniscus-like liquid nanojunction has been studied. For creation and stabilization of liquid nanojunction the scanning probe microscope with glass nanopipette tip has been used. Current to voltage characteristics of liquid nanojunctions in dependence of the concentration of ions in electrolyte and the immersion depth of the pipette into the liquid surface have been measured. In dependence of the experimental parameters both linear and nonlinear current to voltage dependencies and also periodic current oscillations have been observed.
Method of improving the rubidium – 87 quantum frequency standard’s metrological characteristics
Authors: Valov A P , Nagornaya A I , Kulikova M E , Davydov V V , Glinushkin A P
Published: December 2020

The need of using quantum frequency standard in satellite navigation systems is considered. The experimental results of improving the metrological characteristics of the standard using median filtering are presented.
Deposition of a titanium coating on a steel base by contact welding and study of the resulting layered system structure
Authors: Egorov I , Fomin A
Published: December 2020

The paper describes a method for the deposition of a titanium coating on the base of steel grade Cr12MoV for the subsequent modification of the layered system. The resistance welding parameters required for the formation of the “steel – titanium” structure with an increased hardness of 300–800 HV were established.
A theory of flexural modes in graphene
Authors: Raikov I. O. , Conyuh D. A. , Ipatov A. N. , Parshin D. A.
Published: December 2020

We present a theory of flexural modes in graphene. The theory is based on the idea of negative springs in the second coordination circle between next nearest neighbours. As a result these negative springs change the dispersion law of vibrational modes in graphene from phonon-like linear dispersion ω
∝
q to a flexural kind dispersion ω
∝
q
2, when the elastic modulus of the lattice goes to zero. At this point positive springs of the first shell are completely compensated by the negative springs which are 1/6 of the positive springs. Phonons cannot propagate through such a soft lattice with zero Young modulus and sound velocities, but flexural modes can.
Morphology and redispersibility of silver nanoparticles prepared by chemical reduction
Authors: Lukhmyrina T S , Shestakov M S , Shvidchenko A V , Matveev B A
Published: December 2020

In the present work we fabricated and investigated colloidal Ag nanoparticles (NPs). The NPs were synthesized by the chemical reduction method of Ag2SO4 using NaBH4 in the presence of different surfactants. Morphological properties of synthesized colloidal Ag-NPs were studied by ultraviolet-visible (UV-vis) spectroscopy and dynamic light scattering (DLS). Average NP size varied in the range from 3 to 15 nm. Redispersibility of dried NPs with various stabilizers was also investigated and recovered that fish oil is effective stabilizer.
Impact of the piezoelectric response of carbon nanotubes on their memristive properties
Authors: Il’ina M V , Guryanov A V , Osotova O I , Il’in O I , Rudyk N N , Ageev O A
Published: December 2020

The experimental studies of the piezoelectric response of aligned carbon nanotubes (CNT) with different geometric parameters are presented. It is shown that the magnitude of the piezoelectric response increases with decreasing diameter and length of the CNT. It is established that CNT memristive properties improve with an increase of piezoelectric response. The results can be used in the development and creation of energy-efficient storage devices and nanogenerators.
Measurements of sub-nT dynamic magnetic field shielding with soft iron and mu-metal for use in linear colliders
Authors: Gohil C. , Burrows P.N. , Kraljevic N. Blaskovic , Schulte D. , Heilig B.
Published: December 2020

There is an increasing need to shield beams and accelerator elements from stray magnetic fields. The application of magnetic shielding in linear colliders is discussed. The shielding performance of soft iron and mu-metal is measured for magnetic fields of varying amplitude and frequency. Special attention is given to characterise the shielding performance for very small-amplitude magnetic fields.
Explaining successful and failed investments in U.S. carbon capture and storage using empirical and expert assessments
Authors: Abdulla Ahmed , Hanna Ryan , Schell Kristen R , Babacan Oytun , Victor David G
Published: December 2020

Most studies of deep decarbonization find that a diverse portfolio of low-carbon energy technologies will be required, including carbon capture and storage (CCS) that mitigates emissions from fossil fuel power plants and industrial sources. While many projects essential to commercializing the technology have been proposed, most (>80%) end in failure. Here we analyze the full universe of CCS projects attempted in the U.S. that have sufficient documentation (N=39)—the largest sample ever studied systematically. We quantify 12 project attributes that the literature has identified as possible determinants of project outcome. In addition to costs and technological readiness, which prior research has emphasized, we develop metrics for attributes that are widely thought to be important yet have eluded systematic measurement, such as the credibility of project revenues and policy incentives, and the role of regulatory complexity and public opposition. We build three models—two statistical and one derived through the elicitation of expert judgment—to evaluate the relative influence of these 12 attributes in explaining project outcome. Across models, we find the credibility of revenues and incentives to be among the most important attributes, along with capital cost and technological readiness. We therefore develop and elicit experts’ judgment of 14 types of policy incentives that could alter these attributes and improve the prospects for investment in CCS. Knowing which attributes have been most responsible for past successes and failures allows developers to avoid past mistakes and identify clusters of near-term CCS projects that are more likely to succeed.
Optimization of Binding, Washing and Elution Buffer for Development of DNA Isolation Kit
Authors: Weng Chong Li , Yazid Hafiz , Appalasamy Suganthi , Geng Boon Jia , Nasir Wan Mohd Nazdrol Wan Mohd , Muhammad Nik Maheran Nik , Iman Abd Hamid Mar , Kumaran Jayaraj Vijaya
Published: December 2020

DNA isolation is one of the most crucial part in DNA analysis and is reflected by the abundance of ready-to-use DNA isolation kits available in the market. However, the chaotropic salts used in conventional kits during the binding step has been known to inhibit the downstream process of PCR and deteriorate when exposed to air. This study aims to design a better and faster DNA isolation process with better DNA isolation performance to replace the conventional one. This study aims to replace the chaotropic salt in binding buffer with organic acids or salt and improve the buffer used during the wash step. Sodium perchlorate and several other salts and acids were chosen as candidates for the binding buffer. Simultaneously, 10Mm NaCl and 10Mm Tris-Cl with varying concentrations of organic solvents were selected as candidates for the wash buffer. The performance of the selected buffers was then compared to the readily available commercial kit. Organic acid B was among the best candidates for binding buffer with 81.91% and 83.20% recovery rates. For wash buffer, it was observed that the DNA recovery increases with an increasing organic solvent concentration in 10Mm NaCl and 10Mm Tris-Cl. Wash buffer with 90% organic solvent shows the best compromise of DNA yield and purity compared to 70%, 80%, and 100% organic solvent concentration in 10Mm NaCl and 10Mm Tris-Cl. A combination of organic acid B in binding buffer and 90% organic solvent A in wash buffer were tested against a commercial DNA extraction kit. The combination of organic acid B and 90% organic solvent yielded 72.81 ng/ul compared to 28.46 ng/ul by the commercial kit. The combination of the binding buffer organic acid B and 90% organic solvent in 10Mm NaCl and 10Mm Tris-Cl can replace the current commercial kits without the problems posed by the presence of chaotropic salt.
Evaluation of long-term storage effects on buccal cell DNA from untreated cards for STR profiling
Authors: Hakim Hashom Mohd , Lalung Japareng , Khan Hussein Omar , Ismail Siti Afifah , Aziz Mohd Yusmaidie , Ishak Ahmad Razali , Safuan Sabreena , Rasudin Nur Syahmina , Chambers Geoffrey Keith , Edinur Hisham Atan
Published: December 2020

The success of DNA profiling using long-term stored samples depends on the amount and quality of their recovered DNA templates. Physical and biochemical factors such as microbial activity, humidity and temperature contribute to DNA degradation. In this study, we used genomic DNA extracted from buccal cell samples that were stored for more than 4 years on Bode Buccal DNA Collector™ cards (Bode Technology, Virginia, USA) for typing 27 and 24 short tandem repeat (STR) loci using Powerplex® Fusion 6C system (Promega Corporation, Madison, USA) and Globalfiler™ Express kit (Thermo Fisher Scientific, USA), respectively. Our results demonstrated that the Buccal DNA Collector can be used as a collection medium for buccal swab samples that are not immediately analyzed or those that need to be retrospectively analyzed. There is a sign of DNA degradation which might well be expected because buccal cell samples were deposited on untreated filter paper and have been stored for a long period (> four years) at room temperature. However, STR allele calls were obtained from most of the buccal cell samples, especially when typed using the Powerplex® Fusion 6C system kit.
Optimal Hypochlorite Bleaching Duration for Sesbania grandiflora Pulp
Authors: Xian Liew Jing , Geng Boon Jia , Nadhari Wan Noor Aidawati Wan , Peng Leh Cheu
Published: December 2020

Sesbania grandiflora is a fast growing species with 3 to 4 years of harvest rotation. Meanwhile, high cellulose content of the plant has made it a potential commercial pulpwood in Malaysia however the information is limited. Bleaching is an important process in pulp and paper manufacturing. Sodium hypochlorite was commonly used as the bleaching agent due to its strong oxidising bleaching in brightening the pulp. To reveal potential of Sesbania grandiflora as pulpwood, this research was carried out to determine the optimal duration by bleaching the Sesbania grandiflora with sodium hypochlorite. Sesbania pulp was treated with 5.00wt% of sodium hypochlorite solution in the water bath under the temperatures of 50°C. Three bleaching durations were taken: 20mins, 40mins and 60mins. The procedures of laboratory handsheets making and testing were conducted according to modified TAPPI standard. The results proved that 60mins was the optimal bleaching duration which showed the highest brightness percentage and the least lignin content. The reduction of lignin content also the kappa number had contributed to the brightness of the pulp. However, the overall strength properties of the Sesbania handsheets such as bursting test, tearing test and folding endurance test were decreased due to the fibre degradation when bleaching. The optical properties and strength properties of bleached handsheets showed significantly difference as compared to the unbleached handsheets and the differences become obvious as the bleaching duration increase.
Effect of Portions and Particle Sizes on Proximate Properties of Oil Palm Fronds
Authors: Sirrajudin Mohamed Sharizal , Salam Mohammed Abdus , Ahmad Azlan bin , Rak Aweng Eh , Mohamed Mazlan
Published: December 2020

The purpose of proximate analysis is basically to evaluate the fuel characteristics of raw materials. So, the aim of this study is to evaluate the effect of portions and particle sizes on proximate properties of oil palm fronds. The moisture analyser mx-50 machine was used in the identification of moisture content (MC) in the samples. Meanwhile, volatile matter (VM) was analyze based on BS EN 15148:2009 standard. Ash content (AC) was obtained using BS EN 14775:2009 standard. On the other hand, fix carbon (FC) was obtained through the summation of percentage in all three (3) different values of moisture content, ash content and volatile matter subtracted from 100%. The average percentage of MC of bottom, middle and top portion of oil palm fronds for smaller particle size (0.5mm) were 11.91±0.25%, 12.23±0.14%, 12.59±0.23% respectively. On the other hand, the average percentage of MC of the same portion of oil palm fronds for bigger particle size (1.5mm) were 10.67±0.41%, 11.25±0.12%, 11.53±0.23% respectively. Meanwhile, the average percentage of VM of the same portion of oil palm fronds for smaller particle size (0.5mm) were 81.02±0.28%, 80.68±0.33%, 80.15±0.19% respectively. The average percentage of VM of the same portion of oil palm fronds for bigger particle size (1.5mm) were 82.48±0.32%, 82.48±0.32%, 81.26±0.26% respectively. The average percentage of AC of the same portion of oil palm fronds for smaller particle size (0.5mm) were 2.48±0.15%, 2.63±0.16%, 2.85±0.70% respectively and for bigger particle size were 2.23±0.11%, 2.46±0.71%, 2.67±0.50% respectively. Last but not least the average percentage of FC of the same portion of oil palm fronds for smaller particle size were 4.59±0.26%, 4.46±0.60%, 4.41±0.11% respectively and for bigger particle size were 4.62±0.33%, 4.57±0.15%, 4.54±0.02% respectively. Based on the results of proximate analysis above, it can be concluded that, oil palm fronds has a potential to be utilized as solid fuel.
Observation of Arc Behaviour in TIG/MIG Hybrid Welding Process
Authors: Ellyana Roslan Rose Alifah , Mamat Sarizam , Teo Pao Ter , Mohamad Firdaus , Gudur Srinath , Toshifumi Yuji , Tashiro Shinichi , Tanaka Manabu
Published: December 2020

In this project, the influence of TIG currents’s variation on arc stability of TIG/MIG hybrid welding was studied by comparing with MIG welding process. The welding current-voltage waveform was analyzed to characterize the arc stability of the MIG arc. From the observations, the introduction of TIG arc as low as 60 A of current significantly change the MIG arc stability in TIG/MIG hybrid welding. The length of MIG arc in TIG/MIG welding increased with the introduction of the TIG arc as compared with MIG welding. The increase of arc length was due to the arc interaction between the TIG arc and MIG arc, which is affecting the wire melting rate. At the maximum TIG current, the diameter of the molten droplet decreased with the increment of droplet transfer frequency.
Adsorption of Methylene Blue from Aqueous Solutions Using Parkia speciosa Pod-based Magnetic Biochar
Authors: Rao Thevisri Hannanda , Mohammad Rosmawani , Shoparwe Noor Fazliani
Published: December 2020

This study was aimed to investigate the use of Parkia speciosa pod (petai pod) in the form of magnetic biochar as an efficient bioadsorbent to remove methylene blue (MB) in batch mode. The adsorption onto the magnetic biochar achieved about 99% of removal for all the initial concentrations studied (25 mg/L – 250 mg/L). The adsorption processes were studied using the adsorption isotherms, which were analysed using Langmuir and Freundlich model. The adsorption using magnetic biochar followed Freundlich model, indicating the heterogeneous surface of the magnetic biochar. Thus, the study showed that the Parkia speciosa pod (PSP) as agricultural waste has the potential to be used as a low-cost adsorbent.
Effect of alumina addition on physical and structural properties of ceramic porcelain
Authors: Ibrahim Norfadhilah , Ya’akob Nur Hidayah , Yusoff Mahani , Nor Amal Najihah Muhamad
Published: December 2020

Porcelain usually made up of kaolin, feldspar, silica and alumina have properties as an electrical insulator. The effect of adding different amounts of alumina into the porcelain composition has revealed the positive possibility in the production of the ceramic insulator. The different types of raw materials which are feldspar, silica, kaolin and alumina used in the production of porcelain insulator samples by varying their composition. The properties of the porcelain sample after being sinter at 900 °C were identified according to their physical and structural properties. The porcelain sample properties were investigated using XRD, XRF and density test. The presence of corundum, quartz, albite and mullite phases was believed to increase the physical and structural strength of the porcelain sample.
Drying properties of Sentang (Azadirachta excelsa) dried under different temperatures
Authors: Mohamad Ruddin Noor Zulai’ha , Rasid Shaharlina , Hermawan Andi
Published: December 2020

In this study, we investigated the drying properties of Sentang (Azadirachta excelsa) dried at different temperatures. Sentang tree planted in Kelantan, Malaysia, was used in this study. Drying specimens with dimensions of 30 ×150 × 500 mm were dried under air-drying conditions, a constant temperature of 60, 80, 100, and 120 °C until the moisture content (MC) of the specimens reaches an equilibrium moisture content (EMC) at each drying condition. The drying properties of the specimens were then examined. The results confirmed that drying temperature had a significant effect on drying time. As expected, drying Sentang under air-drying conditions demanding considerable time than the other drying conditions.
Preparation & Characterization of Microcrystalline Cellulose from Agriculture Waste
Authors: Senusi Nur Aiman , Mohd Shohaimi Norshahidatul Akhmar , Halim Ahmad Zamani Ab , Shukr Nurasmat Mohd , Abdul Razab Mohammad Khairul Azhar , Mohamed Mazlan , Mohd Amin Mohamad Asyraf , Mokhtar Wan Nur Aini Wan , Ismardi Abrar , Mohamed Noor An’Amt Bin , Abdullah Nor Hakimin
Published: December 2020

In this work, microcrystalline cellulose was prepared from oil palm trunk by water treated fibre process and alkali bleaching. The prepared samples were characterized by using Fourier-transform infrared spectroscopy attenuated total reflectance (FTIR-ATR), Scanning Electron Microscopy (SEM) and X-ray diffraction (XRD). FTIR-ATR spectra analysis indicates the presence of the hydroxyl group, alcohol, alkane/alkene and imine group. XRD patterns revealed the amorphous nature of the samples and the crystallinity index for extracted cellulose is 48.7 %. SEM images showed the fibrous structure of the microcrystalline cellulose with a size of 50 μm. This research proved that the synthesized microcrystalline cellulose could be potentially used as reinforcement in bio composite for better performance and ductility.
Synthesis of Sodium Alginate Graphene Oxide-Silver Film for Antibacterial Activity
Authors: Mohd Zin Farah Amanina , Noor An’amt Mohamed , Mohd Nasri Wan Nurshafeera Wan , Roslan Nurul Natasya , Buniamin Nur Aqilah , Abdul Razab Mohammad Khairul Azhar , Mat Rasa Mohd Sukhairi , Abdullah Nor Hakimin , Mohd Amin Mohamad Faiz , Wei Lee Seong , Rameshkumar Perumal
Published: December 2020

A facile preparation of graphene oxide silver alginate film (GO-Ag) has been constructed for the antibacterial activity. Graphene oxide (GO) was used as a substrate towards arranging of unagglomerated silver nanoparticle (AgNPs) by a simple microwave irradiation on combination of GO and silver complexes in the presence of alginate. The obtained nanocomposite were characterized by using Ultraviolet-visible spectroscopy (UV-Vis) and Xray Diffraction to confirm the formation of film composite. AgNPs with spherical-shape deposited on the GO Alginate layer which displayed a good antibacterial towards E.Coli and Staphylococcus aureus.
Optimization And Kinetic Analysis On The Production Of Hyaluronic Acid By Streptococcus Zooepidemicus In A Batch System
Authors: Shoparwe Noor Fazliani , Kew Wee Seng , Mohamad Mardawani , Ameram Nadiah , Zaini Makhtar Muaz Mohd
Published: December 2020

In this study, the optimization and kinetic analysis on the effect of process parameters for the production of hyaluronic acid production by S. zooepidemicus were performed in batch system. The fermentation condition such as inoculum size (2 to 20 %), pH (4 to 10), temperature (30 to 45) and agitation (50 to 500) were optimized using “one-factor-at-a-time” method. It was found that the inoculum size of 10 % had the greatest effect on the fermentation process which gave the highest value of specific growth rate, cell biomass and HA production of 0.72 h−1, 1.96 gl−1 and 0.82 gl−1, respectively. Furthermore, the other process parameters such as pH, temperature and agitation speed were also found to improve the cell biomass, HA production and kinetic analysis. The highest cell biomass (0.17 gcell gglucose−1) and HA yield (0.096 gHA g glucose−1) were obtained at pH 7.0, 37 °C and agitation speed 300 rpm for 12 h. The overall kinetics analysis of maximum specific growth rate, volumetric cell biomass productivity and volumetric HA productivity obtained at optimum parameters were, 0.81 h−1, 0.183 gcell l−1 h−1 and 0.111 gHA l−1 h−1, respectively.
Heavy Metals Accumulation in River Water and Sediment Core at Kelantan River Tributaries of Gua Musang, Kelantan
Authors: Yusoff Abdul Hafidz , binti Zali Nur Athirah , Chang Chang Shen , Shoparwe Noor Fazliani , Ter Teo Pao , Zakaria Khairul Anam , lazim Azwan Mat
Published: December 2020

Several rivers around Gua Musang had been suspected as polluted area due to waste discharge from ore mining and palm oil factories located near the rivers. However, more evidence is needed to support the statement. Therefore, this study had been carried out to determine the water quality of Aring, Lebir and Relai Rivers at Gua Musang, Kelantan via its physiochemical parameters. Elemental concentrations of Fe, Al, Mn, Zn and Pb were determined in both water samples and sediment cores collected from Aring, Lebir and Relai Rivers to evaluate the accumulation trend of the heavy metal. The pollution level of heavy metals in Aring, Lebir and Relai Rivers were then investigated by using geo-accumulation index. The heavy metals of sediment were analysed by Atomic Absorption Spectrometer (AAS) after being digested by an acid mixture of HNO3/HCL (1:3; v/v). This study shows that Aring, Lebir and Relai Rivers need to treated before direct consumption. The horizontal spatial distribution of heavy metals in water and sediment suggests that the rivers were contaminated with Mn, Fe, Al and Zn. Although Aring Rivers shows the highest concentration of Mn in both water and surface sediment, the inconsistent trend of vertical profiling of heavy metals through sediment cores shows Lebir River has the highest Fe, Pb, Zn and Al geoaccumulation while Relai River has the highest Mn geoaccumulation.
Traditional Processing Method of Smoked Corbicula fluminea (Etak): Case of Etak Vendor in Kelantan, Malaysia
Authors: Rak Aweng Eh , Azizan Ahamad Tarmizi , Yaacob Mohd Rafi , Hamzah Zulhazman , Syed Omar Sharifah Aisyah , Zakaria Mohd Nazri , Ismail Mohamad , Wan Ibrahim Wan Khairy , Mohamad Rani Wan Siti Farizan , Zaki Mohd Zaim , Mohammed Arifullah
Published: December 2020

Traditional knowledge is very synonymous with communities and tribes around the world, especially indigenous peoples or in Malaysia known as Orang Asli. This knowledge is borne out of the constraints faced by society in daily life and often passed down from generation to generation. All aspects of life in the community such as traditional medicines, pest and disease control, farming method, tools used in the preparation of soil and roads, methods of food preparation and so on are assisted by the traditional knowledge created by the community itself. Asian clams (Corbicula fluminea), locally known as “etak” in Kelantan dialect, Malaysia, has been consumed by the local community as a snack for a years. Smoked “etak” is prepared traditionally using freshly harvested “etak” from the river or natural habitat. Freshly harvested “etak” is then washed thoroughly and soak overnight to remove sand and dirt. Followed by, marinating with the previously prepared spices and soak for about 2 hours. The last process is to smoke the “etak” on the fire with medium heat. “Etaks” are placed on a platform made of bamboo with height of about one meter above the ground. Beneath it was lighted with firewood and before “etak” can be placed on a bamboo platform, it was necessary to make sure that the firewood is burned to the coals. This is to ensure that the “etak” shell is not opened as it is considered to be damaged and should not be eaten as a snack. “Etak” with shell open will dry and lose its juiciness and flavor. “Etak” should be stirred all the time when it is on a platform with medium heat fire. “Etak” is usually smoked for about 45 minutes and left to cool down before eating or selling. Based on an interview and observation conducted, it can be concluded that smoked “etak” which is prepared using traditional method is preferred by consumers, as it has a unique aroma and flavor. Hence, the current study aims to document this knowledge through informal conversational interview with “etak” smokers and consumers in Kelantan as well as observing the working mechanism of this method.
Assessment of metal concentrations in Polymesoda expansa from Sungai Geting, Tumpat, Kelantan and associated health risk
Authors: Idris Nor Shahirul Umirah , Jury Nuramalia , Mohd Talib Nurul Afiqah , Abdul Halim Nurul Syazana , Yaakub Nadzifah , Marican Nor Dalila
Published: December 2020

The spatial distribution of lead, zinc, cadmium, copper, and arsenic in Polymesoda expansa from Sungai Geting, Tumpat Kelantan were determined with inductively coupled plasma – mass spectrometer, in comparison to the levels in their surrounding water body. The objectives of this research was to determine the possible health risks associated with heavy metal accumulation via consumption of Polymesoda expansa by using Target Hazard Quotient (THQ). The data indicate have associations between the concentrations of metal measured in study sampled and the levels observed at the sites. The results suggested that the concentration of arsenic in Polymesoda expansa was relatively higher than those studied elements. The concentration of arsenic in studied sample demonstrate the sources of the antropogenic inputs. In terms of risk assessment, concentrations of metals in Polymesoda expansa were significantly below the Malaysian Food Regulation 1985.
Four New Records of Zingiberaceae in Gunung Telapak Burok, Berembun Forest Reserve (Fr), Negeri Sembilan
Authors: Appalasamy S. , Arumugam N.
Published: December 2020

A short survey on Zingiberaceae family was done in selected trails of Gunung Telapak Burok (1193m), Berembun Forest Reserve (FR), Negeri Sembilan. This botanical inventory for ginger family produced a list of 10 genera and 14 species, including four new records for Berembun Forest Reserve (FR) and Negeri Sembilan. Most gingers species found were from genusAlpiniaand followed byGlobba. Alpinia vitellina(Lindl.) Ridl. Four species namely Meistera ochrea (Ridl.) Skornick & M.F.Newman(Amomum ochreumRidl.),Camptandra ovataRidl.,Zingiber longibracteatumTheilade andConamomum utriculosumRidl.(Amomum utriculosum(Ridl.) Holtum) were not listed during previous botanical survey and were additional new records for Berembun Forest Reserve and Negeri Sembilan. The previous record also foundHaniffia cyanescensvar.cyanescenswhich is a hyper-endemic wild ginger in Bukit Tangga. In this survey, the species was collected in Gunung Telapak Burok. This flowering species was found to be a rare sighting in Gunung Telapak Burok. Some of the species found in Gunung Telapak Burok were found in less localities (less than five) especiallyZ. longibracteatumin Peninsular Malaysia. Thus this forest area must be preserved for its species richness especially in wild gingers.
Short Notes on Traditional Vegetables Consumed by Jahai Tribe in Klewang Village, Royal Belum State Park, Malaysia
Authors: Aweng E R , Suganthi A , Nivaarani A , Aisyah S O Sharifah , Choo A Mohd Radhi , Salam M.A. , Zulhazman H
Published: December 2020

Indigenous people are known for their lives blended with the environment. The resource for their survival was procured from their surrounding nature, including the traditional vegetables. Not much is known about the traditional vegetables species that they consumed and the ones they don’t. A simple survey was conducted among the Jahai aboriginal community in Klewang Village, Royal Belum State Park, on 5th March 2020. The study was conducted randomly using face-to-face interviews and surveys to identify the traditional vegetables found and consumed in the villages. The habitats of these traditional vegetables were recorded and the plants were collected and photographed for identification and live specimens were planted at Agro Techno Park, Universiti Malaysia Kelantan, Jeli Campus. All species were identified using spot characters such as inflorescence and leaf morphology. Survey results showed that there were seven species of traditional vegetables including planted and wild grown, namely, sweet potato (Ipomoea batatas), cassava (Manihot esculenta), purple milletia (Morus atropurpurea), torch ginger (Etlingera elatior), pigweed (Amaranthus viridis), Indian mulberry (Morus citrifolia) and wild eggplant (Solanum torvum). Out of these seven traditional vegetables, there are only three vegetable species that are not consumed by this tribe: pigweed (A. viridis), Indian mulberry shoots (M. citrifolia) and purple milletia shoots (M. atropurpurea).
The diversity of small mammals in a mixed fruit orchard at Bukit Bekong limestone massif, Merapoh, Pahang, Malaysia
Authors: Muhammad Aminuddin Baqi H F , Mohamad Iqbal N H , Nur Nabilah A R , Nur Ain Aiman A R , Suganthi A , Fong P H , Jayaraj V K
Published: December 2020

The increasing forest fragmentation due to human encroachment has isolated and scattered forest patches and limestone karsts. Agroforestry has been touted as a sustainable solution for the agriculture sector to yield crops and also provide alternative habitats for wildlife outside protected areas and linking forest patches and isolated limestone karsts. This initial survey was conducted to evaluate small mammals (bats and non-volant) assemblages present in a mixed fruit orchard bordering Bukit Bekong limestone massif in Merapoh, Pahang. We captured 193 individuals from 28 species (13 for bats & 15 for non-volant) using mist nets, harp traps and cage traps. This orchard contains Nycteris tragata and Kerivoula pellucida, listed as Near Threatened plus Maxomys rajah as Vulnerable in the IUCN Red List, revealing the fact that this small area in comparison to protected areas possesses unprecedented conservation value. Furthermore, 15 out of 28 small mammal species captured are habitat generalist may provide a cause of concern for the loss of forest specialists. Nonetheless, our results show that less intensively managed agroforest like mixed fruit orchard can also support forest specialists that are sensitive to disturbance. Moreover, the presence of limestone karst nearby contributes to bat diversity, especially cave-roosting bats. In summary, the diversity of small mammals in agroforest is worth to be studied as the species accumulation curve in this one mixed fruit orchard has yet to reach an asymptote. We hope future biodiversity data in agroforest will be incorporated in agriculture management strategies to stimulate sustainable agriculture and promoting mammal diversity.
The response of woody borreria (Hedyotis verticillata Lam.) towards curry leaves (Murraya koenigii (L.) Spreng.) aqueous extract at the vegetative growth
Authors: Hanis Zakaria Noor Iffa , Zain Norhafizah Md , Bristone Basiri , Naher Laila
Published: December 2020

The massive used of synthetic chemical herbicides in crop production to meet the increasing demand had cause negativel impacts on the environment and ecosystem. Allelopathy approach of potential crops is a suitable alternative that should be explored to have sustainable weed management. The present study was conducted to determine the phytotoxic effect of aqueous curry leaves(Murraya koenigii(L.) Spreng.) extract on the emergence and seedling growth of the bioassay species, woody borreria(Hedyotis verticillataLam.) under laboratory and nursery condition. The seed and seedling of bioassay species were treated with different concentration of aqueous curry leaves extract at 0, 20, 40, 60, 80 and 100g/L (laboratory) and 0, 50, 100, 150, 200 and 250g/L (nursery). The results showed that the aqueous curry leaves extract possesses a significant inhibition on seed emergence, shoot fresh weight and radicle length ofH. verticillataat 100g/L concentration, where it reduced by almost 100% when applied as pre-emergence under laboratory condition. Meanwhile, the curry leaves extract at highest concentration of 250g/L significantly reduced the weed shoot fresh weight by 31% as compared to control and 50g/L concentration when treated at soil surface as post-emergence under nursery condition. Conversely, there is insignificant reduction in shoot height and root length ofH. verticillataacross all the applicate rates. These results suggest that curry leaves can be a good source to develop pre-emergence natural herbicide for weed management which is also eco-friendly for the environment and human beings.
Adoption of Post-Harvest Practices Implemented by Fruit Farmers in Johor
Authors: Abu Bakar Tengku Halimatun Sa’adiah T , Man Norsida , Nawi Nolila Mohd , Shah Jasmin Arif
Published: December 2020

The post-harvest practice is important to maintain and prolong the shelf life of fruits and vegetable. However, farmer’s adoption towards agriculture practices is still low. This research aims to determine post-harvest adoption among fruit farmers in Johor. The study employs a Unified Theory of Acceptance and Use of Technology (UTAUT) and Theory Planned Behaviour (TPB) to evaluate the factors that influencing post-harvest practice adoption. 150 fruit farmers in Johor were chosen by using a simple random sampling technique. This study indicates that the level of performance expectations (M=4.27), effort expectations (M=4.36), facilitating conditions (M=3.95), attitude (M=4.09) and post-harvest practices adoption (M=4.33) have a high mean score. This study emphasises the importance of post-harvest practices adoption in improving and maintaining the quality of fruits. Post-harvest practices adoption could help to enhance the per capita availability of fruits because the adoption of post-harvest practises and technologies will affect the reduction in fruits losses, thus increasing the availability of fruits products.
Molecular Identification of Fungi Isolated from Infected Redclaw Crayfish, Cherax quadricarinatus
Authors: Victor Shekinah Shamini , Pahirulzaman Khomaizon A.K
Published: December 2020

In Malaysia, the redclaw crayfish, Cherax quadricarinatus is widely known as freshwater lobster due to its lobster-like appearance and habitat. Even though the exact year in which the redclaw species was introduced into the country is unknown, commercial scale culturing activity of this species has been in record since 2003 in the southern part of Peninsular Malaysia. Crayfish plague is a water mould caused by an oomycete Aphanomyces astaci which contributes for high mortality rate in indigenous crayfish species throughout Europe. However, the effects of the plague can vary among species, regions and local populations. Traditionally, the crayfish plague agent was seen to have only the freshwater crayfish as hosts. The identity of the pathogen is only assumption and not confirmed by research because of difficulties in cultivation and ambiguous morphological characteristics. In this study, we demonstrate the use of ITS86F and ITS4 primer pair to amplify the ITS2 region in the isolated fungi from infected C. quadricarinatus. The primer aligned with sequences from a range of fungal species within the Ascomycota and Basidiomycota clades. A total of 14 fungi were isolated from the infected C. quadricarinatus. With the constructed neighbour-joining phylogenetic tree, 7 of the ITS2 sequences were identified to most closely related to 9 fungal species within the Ascomycota clade, 5 sequences in Basidiomycota clade and 2 sequences were closely related to endophyte culture collection. Results show fungi other than A. astaci, could cause crayfish plague. These isolated fungi might be linked to the A. astaci. Genetic analysis provides easy identification of the large majority of fungi at the species level, regardless when little DNA is available. Moreover, there are very low quantities of the pathogen DNA in the sample that are detectable by some of the molecular methods.
Analysis of Harmonic Characteristics of Pulse Load Based on Switching Functions
Authors: Li Haichao , Wang Jinquan , Huang Kefeng
Published: December 2020

As a kind of special nonlinear load, pulse load (PL) has the characteristics of two typical nonlinear loads. Compared with the traditional rectifier load, the harmonic characteristics of the PL are more complicated. In this paper, the harmonic characteristics of the PL is investigated. By analysing the working mode of the PL, an equivalent circuit model and a switch function model of the PL are introduced. It is analysed that the PL will inject a large number of inter-harmonics and even sub-harmonics in addition to the integer harmonics to the power system, and the harmonics are symmetrically distributed. The experiments were conducted on diesel generator sets (DGS) with PL and public grids with PL. The results show that the established model and analysis method can accurately calculate the harmonic distribution of the system, moreover, the influence of PL mode on harmonic characteristics can be revealed.
MKRVM Prediction of Capacitive RF-MEMS Switching Life
Authors: Bai Yuejiao , He Yigang
Published: December 2020

The elastic coefficient K, a factor affecting the life of capacitive RF-MEMS switch, is selected as the research object. First, we use differential evolution based quantum particle swarm optimization (DE-QPSO) to obtain sparse functions of multiple kernel relevance vector machine (MKRVM), and use the MKRVM algorithm to predict the lifetime of such switches. Then the experimental results show that the method can obtain the health index HI of 3.1043e+06 s, the 3.0657e+06 s. closest to the original data in 0.21 s. At the same time, the conclusion of the longest switching life is obtained when the elastic coefficient is in the range of 4-16 N/m.
Research on risk prediction model for voltage sag based on Elman neural network
Authors: Zhang Pujun , Chen Jingteng , Wu Minhui , Jiang Dongling , Wu Yifan
Published: December 2020

Voltage sag, as a prominent problem among many power quality problems, has always plagued power grids and users. To reduce the loss caused by the voltage sag and provide a basis for the prevention of the voltage sag, it is important to accurately and efficiently predict the risk of the voltage sag. This paper analyses the related factors of voltage sag risk from multi-directional and multi-dimensional, obtains the data of the influence factors of voltage sag risk in various information systems of the power grid, constructs voltage sag multi-source data, and uses Elman neural network to construct voltage sag risk prediction model. Through the training and learning of multi-source data, the model realizes the voltage sag risk assessment of each node in the power grid. Finally, the feasibility and validity of voltage sag risk prediction model are verified by case study of historical monitoring data in Fujian Province, which provides a method for voltage sag risk prediction.
Analysis of shielding failure flash-over rate of collection lines of wind farms in mountainous areas
Authors: Wang Chaoqun , Wang Sen , Ye Lin , Wang Shoufu , Xiang Nianwen , Li Kejie , Yang Ying
Published: December 2020

Aiming at the current situation of serious economic losses caused by lightning shielding on the collection lines of wind farms in mountainous areas. First, this paper uses the horizontal section location map of the collection line to extract the terrain parameters, Then use the catenary equation to determine the spatial position of the conductor and ground of any section of the collector line along the pitch direction, and obtain the height of the conductor and the ground to the ground. Finally, complete the modeling calculation analysis of the three-dimensional electrical geometry model (EGM) of the entire collection line. The calculation results show that, when the thunderstorm day, the arrangement of the collection line and the structure of the tower are the same, the SFFOR of the collection line of the wind farm in mountainous terrain is 0.487 times/100 km/year, and the plain terrain is 0.167 times/100 km/year, that is, mountainous area is 2.9 times of plain terrain; It is recommended to use double lightning protection poles with small protection angles on the collection lines of wind farms in mountainous areas, or install lightning arresters for poles that are prone to flashover to meet the design requirements of line lightning protection.
Visualization of Arc Energy Distribution Based on CCD Image Sensor
Authors: Deng Yunkun , Chen Yingping , Huang Jisheng , Wang Ke , Zhao Xianping , Gao Shuyu , Liu Shuxin , Cheng Yong
Published: December 2020

With the advancement of computer and sensor technology, visualization research has been more and more widely used in the industrial field, especially for arc plasma research of high energy fields. During the electrical breaking process, the DC arc energy distribution directly affects the working performance of the switchgear. A single voltage and current monitoring method is difficult to characterize the complex energy evolution process of the arc. Therefore, the visualization of the arc energy distribution is particularly important. In this paper, the arc energy distribution of the arc combustion process is visualized as the main research content. The arc characteristic detection platform is built, and the voltage, current, contact displacement value and arc image between the contacts are synchronously collected. According to the spectral characteristics of the color CCD image sensor, the colorimetric temperature measurement formula with calibration coefficient is derived to establish the relationship between the pixel and the arc temperature. The acquired arc image is processed by matlab image processing technology to visualize the two-dimensional energy distribution characteristics of the arc in the horizontal projection direction during the breaking process.
Review on operation mechanism and platform architecture of Distributed Energy Storage
Authors: Sun Feng , Li Ping , Liu Siqi , Hao Jiancheng , Ye Peng
Published: December 2020

“Distributed generation and Energy storage technology” has become a widely promoted operation mode to ensure reliable power supply when the distributed generation connected to the grid. In order to realize the unified regulation of energy storage, this paper summarizes the auxiliary operation function, market profit model and market operation mechanism of energy storage from three sides of generation, grid and users. The Distributed Energy Storage Operation Platform constructed through the strategy of “Hierarchical and Partitioned”. The good interaction between energy storage users and power grid realized through the comprehensive services of the platform. Several types of user categories and incentive mechanism under the interaction mode of grid and users sides summarized. Finally, the operation mechanism of distributed energy storage market summarized and prospected.