Yuant Tiandho

University of Bangka Belitung | UBB · Department of Physics

This work presents a high-performance surface plasmon resonance (SPR)-based biosensor for glucose detection. While adding a metal-organic framework (MOF) layer, UiO-66, to the biosensor improves selectivity and enables direct detection without additional receptors, it does not significantly enhance sensitivity. A SPR-based biosensor is proposed to...

This Study aims to determine the effect of the Sun's annual apparent motion on the oscillations of the Subuh prayer time, especially in the city of Pontianak. The research method used is the literature review or reference method. In the literature review, the things that were done included: looking for the schedule of the dawn prayer in the city of...

Permasalahan utama yang umumnya dihadapi para pelaku industri tekstil yaitu berkaitan dengan banyaknya jumlah limbah cair yang dihasilkan. Limbah cair pewarna metilen biru tidak dapat dibuang secara langsung ke perairan karena memiliki tingkat kelarutan yang tinggi dan bersifat non-biodegradable. Oleh karena itu, dalam penelitian ini dilakukan peng...

Dye-sensitized Solar Cell (DSSC) is a solar cell that uses dye as one of its components. DSSC is interesting to develop because it can be fabricated simply with low production costs. This study aims to develop a DSSC that uses dye-sensitized from natural ingredients to be environmentally friendly. We chose betel nut (Areca catechu L.) as a natural...

The increase in the amount of palm oil production impacts increasing the total liquid waste from the processing of palm oil. Palm oil mill effluent (POME) has high chemical oxygen demand (COD) and biochemical oxygen demand (BOD) parameters that can cause environmental pollution. This study processed POME using the Fenton mechanism using reagents de...

Issues related to energy sustainability and carbon emission reduction are continuously being concerned by the Government of the Republic of Indonesia. Various efforts and programs have been launched to achieve targets of the related issues. As known that energy use for cooking by the household is continuously increasing in relation to population gr...

Until now, the world is still facing the spread of the SARS-CoV-2 virus that causes COVID-19. This virus can be transmitted from human to human through droplets, so more vigilance is needed to avoid contracting this virus. One of the steps to minimize the spread of Covid-19 is to wear a face mask. In practice, most people prefer to use cloth masks...

The main weakness in shrimp marketing is the perishable food nature of shrimp. Generally, people identify the freshness of shrimp by direct observation. However, it will be difficult to detect the freshness of shrimp if it is marketed in a closed container. In this study, a label indicator of purple sweet potato will be made to detect the freshness...

One of the common strategies used to minimize the spread of Covid-19 is to wear a cloth mask. Cloth masks have a lower effectiveness value compared to other types of masks but have the potential to be used as an alternative, especially during a pandemic. Smartphone can be used as an initial idea for determining the quality of a cloth mask. In takin...

The presence of dyes in wastewater is one of the main problems in wastewater treatment. Wastewater containing dyes can damage the ecosystem because it can block sunlight into the water and is often accompanied by toxic materials. This paper proposes an alternative method to decolorize dyes in water using CuO as a Fenton-like catalyst, especially fo...

This study aims to synthesize a porous scaffold based on hydroxyapatite and silica using the polymer sponge replication method. In bone tissue engineering technology, the development of porous scaffolds is a topic that is intensively studied because it is expected to be a solution to various problems of conventional bone therapy. In addition to pro...

As an archipelago, handling plastic waste in the Province of Bangka Belitung Islands is an aspect that needs to be taken seriously. Apart from being focused on developing tourist areas, plastic waste will easily be carried to the sea and prone to be degraded into microplastics, often consumed by marine animals. This community service activity focus...

Universitas Bangka Belitung is currently supplied by electricity from the State Electric Company in 690 kVA. Concerning utilizing renewable energy at Universitas Bangka Belitung, the solar power plant is an alternative energy source that will implement. Therefore it is necessary to design a solar power plant with a monitoring system to be known at...

Public awareness of the benefits of honey has increased the amount of honey consumption. This encourages the circulation of impure honey in the market by irresponsible traders. Therefore, characteristic information of honey is needed as a basis for honey purity testing methods. Physical characteristics analyzed in this study are the refractive inde...

The existence of Wild Betta fish in Belitung Island needs to be studied. This study aims to analyze the differences in the morphology of two species of Wild Betta fish from Belitung Island based on the morphometric characteristics and habitat of these fish. The method used in this research is quantitative descriptive. This research was conducted in...

The COVID-19 pandemic that has spread to all countries has changed various human activities in the world. The new habitual adaptation policy is a policy taken by the Government of the Republic of Indonesia to prevent the spread of COVID-19 while still paying attention to the economic sector. Penyak Village is located in Koba District, Central Bangk...

Kegiatan pengabdian berupa Iptek bagi Masyarakat (IbM) merupakan salah satu penerapan Tri Dharma Perguruan Tinggi. Dengan adanya kegiatan pengabdian IbM, maka diharapkan akademisi dapat berinteraksi secara langsung dengan masyarakat. Lokasi yang menjadi sasaran kegiatan IbM adalah Desa Penyak Kecamatan Koba Kabupaten Bangka Tengah yang mayoritas ma...

During the production of batik cual, thick-colored wastewater is produced. Unfortunately, the wastewater could damage the environment if it is disposed of without specific processing. The Fenton method is an advanced oxidation process (AOPs) that can degrade organic dyes found in liquid waste. In this research, the researchers studied the Fenton me...

p>Dye-Sensitized Solar Cells (DSSC) is photovoltaic with a dye that functions as an acceptor of sunlight. The great potential of using DSSC lies in the ease of the synthesis process, and the dyes used can come from plants. However, like most other solar cells, increasing the operating temperature can degrade the DSSC performance and thus decrease t...

Energy sustainability and carbon emission reduction programs are widespread issues in various countries. One sector of concern in the program is the household sector with cooking activities as its focus. Therefore the cooking fuel conversion program is often carried out in various countries and even in Indonesia, such as the program of conversion o...

The potential for solar energy in Indonesia is abundant and attractive to be developed into one of the leading renewable energy sources. Photovoltaic or solar cells are devices that can be used to convert solar energy directly into electrical energy. A dye-sensitized solar cell (DSSC) is an exciting type of solar cell to be developed because it is...

The application of bone scaffolding in bone therapy is an alternative solution developed in bone tissue engineering technology to avoid bone donors' scarcity. The main requirement for a material that can be used as a scaffold is that it is biocompatible. Hydroxyapatite is a calcium phosphate ceramic that is often used as the primary material for sc...

Ikan Cupang alam (Wild Betta) atau dikenal dengan Tepalak oleh masyarakat Sumatera khususnya di Pulau Belitung merupakan komoditas ikan hias lokal potensial budidaya. Keberadaan ikan Tepalak di alam diduga semakin sulit ditemukan karena terjadi penurunan populasi akibat degradasi habitat yang terjadi. Penelitian ini bertujuan untuk mengkaji beberap...

Photovoltaic is a renewable energy source that can optimally be used on outer islands and areas that are difficult to reach by the main electrical system network. With good solar energy intensity on a daily, it adds to the advantages of using photovoltaics. In this regard, it is necessary to make a prototype for monitoring the photovoltaic output p...

Batik cual is one of the leading textile products in the Bangka Belitung Islands. In their production processes resulted dye pollutan in wastewater. Most batik cual industries use synthetic dyes such as remazol brilliant blue royal which can damage the environment if discharge without further treatment. Electrocoagulation is a method that can be us...

Hydroxyapatite is widely known as bioceramics with excellent biocompatibility. Also, hydroxyapatite has biodegradable properties that can support the bone therapy process and can be applied as a bone scaffolds. In recent years, the preparation of hydroxyapatite from natural sources is exciting to be developed. This is because, natural resources, es...

The increasing development of the textile industry is always followed by the amount of wastewater produced. The textile industry uses various types of synthetic dyes, and the amount of dyes is still high in its waste. The impact of the discharge of textile wastewater into the environment without rigorous treatment will damage the environment becaus...

Indonesia is the largest contributor to marine plastic waste in the world after China. One solution to reduce plastic use is to develop a packaging that can be degraded by nature and eco-friendly, called bio-packaging. In this paper, we create bio-packaging made from a composite of waste paper and coconut fiber. In addition to composites’ physical...

Electricity demand of Bangka Belitung Islands Province from time to time always increases. This is caused by the fact that electricity has become an important part of human civilization in various fields including the fields of economy, technology, social and human culture. Electricity distribution to consumers must be optimal in accordance with th...

As a maritime country, shrimp commodity production in Indonesia is very high and continues to increase. However, because shrimp is a perishable food, we need a detection device. This is because conventional methods that are widely used by the community in detecting freshness of shrimp are only based on the smell. Of course, this is a problem when s...

Gauss's law is one of the fundamental laws of physics, especially in the study of electricity. One of the important variable to use Gauss's law is the ability to determine the enclosed charge by the Gaussian surface. Commonly, the definition of the charge distribution of an object is defined by piecewise continuous function. In this paper, a charge...

Hukum Gauss merupakan salah satu hukum fundamental fisika, khususnya dalam kajian listrik. Salah satu variabel penting untuk dapat menggunakan hukum Gauss adalah kemampuan menentukan muatan yang terlingkupi permukaan Gauss. Umumnya, definisi distribusi muatan suatu objek didefinisikan oleh fungsi sepenggal (piecewise continuous function). Pada maka...

Meskipun ilmu fisika merupakan salah satu ilmu yang sangat penting dalam pengembangan teknologi saat ini namun di mata mayoritas peserta didik masih dianggap sebagai ilmu yang sulit dan tidak menarik. Hal ini kemungkinan disebabkan oleh masih banyaknya guru yang hanya menerapkan metode ceramah ketika proses belajar mengajar fisika. Alternatif untuk...

The use of solar energy to satisfy renewable energy in Indonesia has great potential. To improve the efficiency of solar collectors, some researchers proposed solar collectors that equipped by nanofluids as working fluids. CuO-based nanofluids are known as nanofluids that have excellent conductivity. The purpose of this study is to synthesise CuO n...

The output of the photovoltaic cells such as voltage and current is an essential parameter to assess the performance of photovoltaic cells. The performance of photovoltaic cells depends on the intensity of solar irradiation and the cleanliness conditions of cells. One of the factors that influence the performance of photovoltaic cells is shading. I...

Celagen Island is one of the outer islands in Bangka Belitung Islands Province. The population of Celagen island is 1234 people and dominated by fishermen. Currently, electricity is supplied from 1 unit of photovoltaic with capacity 80-kWp and coupled with three units of diesel power plant with capacity 100 kW. To meet the electricity needs of 1069...

Hydroxyapatite is bioceramics which have conducive biocompatible property and have been widely used in bone scaffolds. Although they have potential development, there have not been any matematical model that elaborates the relation between the parameter of synthetic conditons and the mechanical properties of hydroxyapatite. That is why, this articl...

Researchers have synthesized hydroxyapatite-based porous scaffolds by the polyurethane sponge replication methods. Hydroxyapatite was derived from waste cockle shells through the co-precipitation method. The synthesis of porous scaffolds through the sponge replication methods is carried out by absorbing hydroxyapatite slurry through the addition of...

This article presents a model of thermal conductivity of nanofluids based on dimensionless-group methods. In addition to the thermal conductivity of base fluids and nanoparticles, nanoparticle diameter, temperature, and volume fraction of nanoparticles, the proposed model involves several thermophysical parameters such as specific heat, density, an...

Tin mining in the Bangka Belitung Islands Province, leaving a basin called the kulong. Kulong has an irregular landscape and contains very small amount of nutrients. Basically, kulong can be a storage place for water reserves to support the fisheries sector. But often, kulong water has poor dissolved oxygen concentration so that it is not suitable...

CuO-doped SnO2 nanoparticles were successfully synthesized using biosynthetic methods with the pelawan leaf extract. This method is a modification of the sol-gel process by utilizing antioxidant compounds from the leaf extract as a trap-matrix for tin oxides. This research was conducted based on variations in CuO doping. The characteristics of tin...

Nanofluids is a material that has good prospects to increase the efficiency of the heat transfer process. With the addition of small fraction nanoparticles, the thermal conductivity of the nanofluids can increase significantly compared to the fluid base. Although it has excellent application prospects, the study of thermal conductivity models is st...

This study discussed the analysis of load flow before and after the Toboali Substation (GI Toboali) - that is still in development process stage when the paper is written-. This study was operated in a computer simulation using ETAP Software. The Toboali substation needs to be built because Toboali diesel power plant will be shut down because the T...

In this article, we add egg white (albumen) to the synthesis of aluminum oxide nanoparticles (Al 2 O 3 ). Egg white can be used as a trap for the aluminum oxide particle matrix to prevent agglomeration of aluminum oxide particles during the synthesis process. To determine the effect of pH on the characteristics of aluminum oxide crystals formed, va...

Indonesia is one of the largest tin producers in the world. The by-products of processing tin ore in the form of tailings are not used properly. Based on several studies, tin tailings have high levels of silica. In this paper, a silica purification study from tin tailings is proposed using a solid-state method at different pH. The purity of silica...

Bangka Belitung island province is one of the tin producing areas. In the process of processing tin produces a monasite waste in which monasite minerals contain rare earth metals. One application of rare earth elements is as a candidate for RE-Fe-B based magnetic material. In this study, we investigated the magnetic properties of Ce14Fe80B6 thin la...

Bangka Belitung Islands is one of the provinces in Indonesia which has hundreds of small islands. Because the islands are separated from each other it is almost impossible to distribute electricity from the main electricity source in the Bangka Island to all the islands. Because it is located in the tropic country, solar cells can provide an altern...

The high Tin mining activity in the Bangka Belitung Islands caused a considerable amount of environmental damage in the province. One of the most common impacts of contamination is the poor quality of water. Kulong is a former excavation of Tin mines that may be used as a reservoir of water. But most kulong, especially young ones, store acidic wate...

The purpose of this paper is to present a simulation to the inversion methods applied to geophysical exploration. Anapplication of Monte-Carlo, Metropolis, and Simulated Annealing techniques to 1-Dimensional gravity inversion inBayesian framework has been studied. Differences between these methods are observed in both single parameterinversion and...

In many experiments, it has been reported that the performance of solar cells decreases with increasing temperature. This effect arises due to an increase in the intrinsic carrier concentration of material that directly affects the reverse saturation currents ( J0 ). As a result, the open circuit voltage which is inversely proportional to J0 will d...

Nuclear reactors are one of the long-term energy fulfillment solutions. Efforts to increase operating power density at various type of nuclear reactors are programs that are being developed to improve the economic proper ties of a reactor. The use of nanofluids allows nuc lear reactors to operate more optimally through increased critical heat flux...

Activated carbon from ketapang shell (Terminalia Catappa) has been successfully synthesized usingdehydration-carbonization method. Activated carbon was conducted by immersing with sulphuric acid andfollowed by carbonization at 600oC for 2 hours. Pore characteristics were determined using imageprocessingmethods of activated carbon micrographs based...

Abstrak Karbon aktif tempurung Ketapang (Terminalia catappa) telah berhasil disintesis dengan menggunakan metode dehidrasi-karbonisasi. Aktivasi karbon aktif dilakukan dengan menggunakan aktivator asam sulfat yang dilanjutkan dengan karbonisasi pada temperatur 600 o C selama 2 jam. Karakteristik pori ditentukan menggunakan metode pengolahan citra d...

Bangka Belitung Islands is the largest tin producer in Indonesia. The high activity of tin mining caused the environmental damage which had an impact on the emergence of clean water crisis in some areas in this province. In this paper, a simple water quality improvement method based on wasted cockle shell was developed. Based on x-ray diffraction a...

p class="E-JOURNALAbstractBody"> Pada makalah ini dilakukan evaluasi pemahaman mahasiswa tingkat awal terkait konsep gaya gesek yang telah mereka pelajari ketika di sekolah menengah atas. Berdasarkan pengujian awal dapat diketahui bahwa kebanyakan mahasiswa masih mengalami miskonsepsi terkait konsep gaya gesek, khususnya dalam konsep gaya gesek sta...

This paper reconsiders the properties of Hawking radiation in the inner horizon of a Reissner-Nordström black hole. Through the correlation between temperature and surface gravity, it is concluded that the temperature of the inner horizon is always negative and that of the outer horizon is always positive. Since negative temperature is hotter than...

This paper reconsiders the properties of Hawking radiation in the inner horizon of a Reissner-Nordström black hole. Through the correlation between temperature and surface gravity, it is concluded that the temperature of the inner horizon is always negative and that of the outer horizon is always positive. Since negative temperature is hotter than...

Karbon aktif merupakan material amorf yang dihasilkan dari material-material yang mengandung karbon dan memiliki permukaan dalam (internal surface) sehingga memiliki afinitas tinggi untuk menyerap berbagai material tertentu. Karakteristik pori merupakan parameter utama dalam menentukan daya adsorbsi karbon aktif. Dalam makalah ini telah dilakukan a...

In the general theory of relativity (GTR), black holes are defined as objects with very strong gravitational fields even light can not escape. Therefore, according to GTR black hole can be viewed as a non-thermodynamic object. The worldview of a black hole began to change since Hawking involves quantum field theory to study black holes and found th...

In the weak-field limit condition, the gravitational force has a form that is analogous to the electromagnetic force. So that by using the analogy, we may propose the formula that called as gravitoelectromagnetism effect. Like the electromagnetic field, the gravity also predicted to has gravitoelectric field and gravitomagnetic field. In this paper...

Di dalam makalah ini disajikan suatu analisis teoritik dari desain mesin panas foto-Carnot dengan sumber energi berupa lubang hitam non-stasioner. Diharapkan dari kajian ini dapat diketahui potensi penggunaan lubang hitam sebagai sumber “bahan bakar” dari suatu mesin panas. Desain mesin panas berbasis lubang hitam dikembangkan karena melalui mekani...

According to the general theory of relativiy, a black hole is defined as a region of spacetime with super-strong gravitational effects and there is nothing can escape from it. So in the classical theory of relativity, it is safe to say that black hole is a "dead" thermodynamical object. However, by using quantum mechanics theory, Hawking has shown...

p> Currently, a porous material has been extensively developed in many areas of applied science and engineering. The characteristics of porous material is most often determined by its porosity. In this paper, we present a quantitative analysis of pores in a material according to image processing methods. An micrograph from electron microscopy (SEM)...

According to the general theory of relativiy, a black hole is defined as a region of spacetime with super-strong gravitational effects and there is nothing can escape from it. So in the classical theory of relativity, it is safe to say that black hole is a "dead" thermodynamical object. However, by using quantum mechanics theory, Hawking has shown...

Abstrak Umumnya, untuk menggambarkan distribusi massa sebagai fungsi ruang dilakukan pemisahan untuk kondisi di luar dan di dalam objek. Di dalam makalah ini, kami mengusulkan suatu distribusi massa yang berlaku pada kedua kondisi tersebut sehingga tidak perlu dilakukan pemisahan. Jika fungsi tersebut digunakan dalam proses komputasi atau simulasi...

Using Hamilton-Jacobi method, we study the Dirac particles emission from Reissner-Nordstrom-Vaidya (RNV) black hole. The Dirac particles are described by Dirac equation in curved spacetime and emission process is defined as tunneling effect. The probability of Dirac particles emission is related to the Hawking temperature and we obtain that this te...

Infinite square well potential is one of the most elementary quantum mechanical system. The calculation of this case is not too complicated, however, it can show the differences between quantum world and classical world with clearly. In this letter, we expand the discussion about the infinite square well potential for dynamic potential well by invo...

By using the approximation of the weak static gravitational field that is formulated through general relativity we can obtain the Weber's gravitational force equation. The static-weak gravitational field that is used is a solution of the Einstein's equation in the vacuum that satisfy the linear field approximation. The expression of Weber's gravita...

Weber’s gravitational force (WGF) is one of gravitational model that can accommodate a non-static system because it depends not only on the distance but also on the velocity and the acceleration. Unlike Newton’s law of gravitation, WGF can predict the anomalous of Mercury and gravitational bending of light near massive object very well. Then, some...

The purpose of this paper is to present a simulation to the inversion methods applied to geophysical exploration. Application of Monte-Carlo, Metropolis and Simulated Annealing techniques to 1D gravity inversion in a Bayesian framework is studied. Differences between these methods are observed in both single parameter inversion and simultaneous mul...

Aliran fluida merupakan salah satu faktor penting yang perlu dipertimbangkan dalam proses pengolahan minyak. Bentuk aliran fluida dipengaruhi oleh bilangan Reynold fluida tersebut. Karena temperatur dapat mengubah viskositas dan densitas minyak maka nilai bilangan Reynoldnya juga akan dipengaruhi oleh temperaturnya. Nilai bilangan Reynold sebagai f...

Using the Hamilton-Jacobi method, we study the Dirac particles emission of Reissner-Norstrom-Vaidya (RNV) black holes. The Dirac particles are described by the Dirac equation in curved spacetime and the emission process is defined as tunneling effect. The probability of the Dirac particles emission is related to the Hawking temperature and we obtai...

Mekanika kuantum menunjukkan bahwa lubang hitam memiliki temperatur sebagai indikasi dapat mengemisikan partikel. Persamaan transfer panas secara general mengandung operator Laplacian yang sifatnya dipengaruhi oleh ruang. Kelengkungan ruang-waktu di daerah sekitar lubang hitam sangat besar sehingga operator Laplacian untuk menghitung distribusi tem...

Similarity between Newtonian gravitational force and Coulomb's force leads one to define gravitational electric and magnetic fields or gravito-electromagnetic fields. Also, one may define a gravitational Bohr’s theory in analogy with the electromagnetic Bohr’s theory for which the latter is quite successful in explaining some properties of hydrogen...