bluuebunny/crossref_metadata_2025 huggingface dataset:
A Study of Sigma Phase Evolution in Long-Term Creep Tested Super 304H Samples
Authors: Lolla Tapasvi , Siefert John , West Geoff , Gagliano Mike
Published: March 2024

Due to their excellent high temperature oxidation resistance, utilities worldwide are adopting advanced austenitic stainless steels (A-ASS) for critical plant components, such as heat exchangers, as they aim to achieve higher operating conditions. However, challenges may be encountered in developing life assessment and life management strategies for such components. This is because conventional methods used for life assessment, such as measuring steam side oxide scale thickness in ferritic and conventional austenitic material to predict tube metal temperature, may not be successfully applied to A-ASS. In such instances, tracking the formation and evolution of microstructural features during service, may offer a possible method to predict the temperature of these steels. For such metallurgy based lifing strategy to be successful, it is essential to develop a good understanding of microstructure evolution in these steels. In this work one heat of Super 304H, that has been creep tested at 600°C, 650°C and 700°C, with applied stress ranging from 110 to 340 MPa, is characterized using a combination of advanced characterization tools and image analysis methods. The amount of sigma phase formed at the gauge and grip sections of the samples is quantified and the methodology used to quantify this phase is presented. From the results, a time-temperature-transformation diagram for sigma formation is developed.
Experimental Study of Extruded Powder Metallurgy γ-TiAl Based Alloys
Authors: Huvelin Z. , Perrut M. , Bachelier-Locq A. , Sallot P.
Published: March 2024

In the context of research of lighter and/or stronger high temperature materials in order to improve aeroengines, the present work shows an example of a powder metallurgy (PM) manufacturing route for TiAl alloys that could be used for low pressure turbine (LPT) blades processing. In this frame, two different alloys, Ti-47Al-1Fe-1Zr-1Mo-0.2Si (at. %) FZM and Ti- 43.5A1-4Nb-1Mo-0.1B (at.%) TNM-B1, were gas-atomized into powders, extruded, heat-treated and mechanically tested.
Effect of Heat Treatment on Microstructure and Mechanical Properties of Dual Two-Phase Ni3Al and Ni3V Intermetallic Alloys
Authors: Ioroi Kazushige , Kaneno Yasuyuki , TakasugiI Takayuki , Semboshi Satoshi
Published: March 2024

So-called Ni base dual two-phase intermetallic alloys are composed of primary Ni3Al (L12) phase precipitates among eutectoid microstructures consisting of the Ni3Al and Ni3V (D022) phases. In this article, microstructural refinement of an alloy with a nominal composition of Ni75Al10V15 (in at.%) was attempted by various heat treatment processes. When the alloy was continuously cooled down after solution treatment, fine and cuboidal Ni3Al precipitates were developed by rapid cooling while coarse, rounded and coalesced Ni3Al precipitates were developed by slow cooling. When the alloy was isothermally annealed at temperatures above the eutectoid temperature, the morphology of the Ni3Al precipitates changed from fine and cuboidal one to large and rounded one with increase in annealing time. When the alloy was annealed at temperatures below the eutectoid temperature, the Ni3Al precipitates were grown keeping cuboidal morphology. The morphological change from the cuboidal to rounded Ni3Al precipitates was induced by the transition from the growth driven by elastic interaction energy between the precipitate and matrix to that by the surface energy of the precipitate. Fine and cuboidal Ni3Al precipitates generally resulted in high hardness.
Effect of Dissolved Oxygen Level on Stress Corrosion Cracking Susceptibility of Structural Steels
Authors: Jun Jiheon , Raiman Stephen S. , De Las Casas Aranda Rogelio , Pint Bruce A.
Published: March 2024

Stress corrosion cracking (SCC) is a potential risk in structural steels used for steam boilers. To investigate the effect of dissolved oxygen (DO) on SCC susceptibility, three steels, T23, T24 and T91 were annealed at 1065°C and then quenched to create a susceptible microstructure and then exposed in a Jones test to stagnant and circulating water at 200°C with varying DO levels. The results indicated that among the tested steels, the SCC susceptibility was highest in T91 but lowest in T23 which did not exhibit crack initiation with 100 ppb DO. T24 showed no cracking with 50 ppb DO but cracked with 100 ppb DO under these conditions. Based on these results, the next planned step is to monitor crack growth in-situ and determine a critical DO content for each material.
Long-Term Performance of High Temperature Alloys in Oxidizing Environments and Supercritical CO2
Authors: Deodeshmukh V. P. , Pint B. A.
Published: March 2024

Long-term performance of high temperature alloys is critically linked to the oxidation behavior in power generation applications in wet air and steam. As power generation systems move towards higher efficiency operation, nextgeneration fossil, nuclear and concentrating solar power plants are considering supercritical CO2 cycle above 700°C. Wrought solid solution strengthened and precipitations strengthened alloys are leading candidates for both steam and Supercritical CO2 power cycles. This study evaluates the cyclic oxidation behavior of HAYNES 230, 282, and 625 alloys in wet air, flowing laboratory air, steam and in 1 and 300 bar Supercritical CO2 at ~750°C for duration of 1000 -10,000h. Test samples were thermally cycled for various times at temperature followed by cooling to room temperature. Alloy performances were assessed by analyzing the weight change behavior and extent of attack. The results clearly demonstrated the effects of alloy composition and environment on the long-term cyclic oxidation resistance. The extents of attack varied from alloy to alloy but none of the alloys underwent catastrophic corrosion and no significant internal carburization was observed in supercritical CO2. The performance of these alloys indicates that these materials are compatible not only in oxidizing environments, but also in Supercritical CO2 environments for extended service operation.
Research on On-line Detection Technology of Oxide Scale Based on Magnetic Sensitivity and Granularity Behavior
Authors: Aijun Yan , Zhigang Li , Hongnian Dong , Yue Qiao , Chen Hao , Shunsen Wang , Li Fang , Jingru Mao , Kang Chen , Jiacheng Wang , Jingyi Du
Published: March 2024

The oxide exfoliation is one of the main problems that cause the explosion of superheater or reheater, which threaten the safety of power plant units, but there is no direct test method of the particle concentration of the scales in high temperature steam. Based on the study of ferromagnetic and optical characteristics of scales, the technology and equipment were developed for on-line measurement based on magnetic sensitivity and granularity behavior. Through numerical simulation and dynamic simulation experiments of scale movement under high temperature and high pressure steam, calculating method of the particle concertation of scales in the main steam or reheated steam pipeline was retrieved by local sampling concentration.
Approaches to Modeling Fireside Corrosion of Superheater/Reheater Tubes in Coal and Biomass Fired Combustion Power Plants
Authors: Simms N J , Ekpe B , Riccio C , Mori S , Sumner J , Oakey J E
Published: March 2024

The combustion of coal and biomass fuels in power plants generates deposits on the surfaces of superheater / reheater tubes that can lead to fireside corrosion. This type of materials degradation can limit the lives of such tubes in the long term, and better methods are needed to produce predictive models for such damage. This paper reports on four different approaches that are being investigated to tackle the challenge of modelling fireside corrosion damage on superheaters / reheaters: (a) CFD models to predict deposition onto tube surfaces; (b) generation of a database of available fireside corrosion data; (c) development of mechanistic and statistically based models of fireside corrosion from laboratory exposures and dimensional metrology; (d) statistical analysis of plant derived fireside corrosion datasets using multi-variable statistical techniques, such as Partial Least Squares Regression (PLSR). An improved understanding of the factors that influence fireside corrosion is resulting from the use of a combination of these different approaches to develop a suite of models for fireside corrosion damage.
Investigating the Electrical Resistance Technique for Structural Alloy Corrosion Monitoring within Supercritical CO2 Power Cycles
Authors: Walker Matthew , Chames Jeff , Cebrian Javier , Vega Heidy
Published: March 2024

Structural alloy corrosion is a major concern for the design and operation of supercritical carbon dioxide (sCO2) power cycles. Looking towards the future of sCO2 system development, the ability to measure real-time alloy corrosion would be invaluable to informing operation and maintenance of these systems. Sandia has recently explored methods available for in-situ alloy corrosion monitoring. Electrical resistance (ER) was chosen for initial tests due the operational simplicity and commercial availability. A series of long duration (>1000 hours) experiments have recently been completed at a range of temperatures (400-700°C) using ER probes made from four important structural alloys (C1010 Carbon Steel, 410ss, 304L, 316L) being considered for sCO2 systems. Results from these tests are presented, including correlations between the probe measured corrosion rate to that for witness coupons of the same alloys.
Status of Large Scale Manufacture of Nickel Alloy Turbine Rotor Forgings for A-USC Steam Power Plants
Authors: Donth B. , Blaes N. , Diwo A. , Böttcher D.
Published: March 2024

The need to reduce carbon dioxide emissions of new fossil power plants is one of the biggest challenges of mankind in the next decades. In this context increasing net efficiency is the most important aspect which has led to the development of not only new steels for potential plant operation up to 650°C, but also to forged nickel alloys for 700°C and maybe 750°C. For steam temperatures of 700°C Alloy 617 and variants like TOS1x have been already intensively investigated, and manufacturability of large rotor parts was demonstrated. For operation temperatures of 750°C, only the use of γ‘ age-hardenable nickel base alloys is possible. Alloy 263 is one of the most promising alloys for manufacturing large forged components. For this material grade Saarschmiede has produced successfully a large rotor forging for the first time. Considering the complexity in manufacturing large nickel base alloy forgings, the implementation of simulation tools for calculation and optimization of production parameters becomes especially important. Numerical simulation methods are essential to predict material behavior and to optimize material quality-related manufacturing steps. In reference to mechanical properties, microstructure, uniformity of chemical composition FEM computer simulations for the key manufacturing processes re-melting, forging and heat treatment are in application. This paper will present the current status of production of very large prototype nickel base alloy rotor forgings for 700°C and 750°C A-USC power plants. Test results of an Alloy 617 large full scale turbine rotor component recently with improved properties produced will be highlighted. Experiences and results in applying numeric simulation models to ingot manufacturing and forging will also be reported.
Analysis of Steam Valve Jam of Turbine Served for 8541 Hours at 600 °C
Authors: Fan Z.D. , Ma J.M. , Ke Y.J. , Zhang Z.B. , Liu L.C. , Ma Y.C. , Yan A.J.
Published: March 2024

Both of high pressure main throttle valves and one governing valves were jammed during the cold start of steam turbine served for 8541 hours at 600 °C in an ultra supercritical power plant. Other potential failure mechanisms were ruled out through a process of elimination, such as low oil pressure of digital electro-hydraulic control system, jam of orifice in the hydraulic servo-motor, and the severe bending of valve stem. The root cause was found to be oxide scales plugged in clearances between the valve disc and its bushing. These oxide scales are about 100~200 μm in thickness while the valve clearances are about 210~460 μm at room temperature. These oxide scales are mainly composed of Fe3O4 and Fe2O3 with other tiny phases. Both of valve disc and its bushing were treated with surface nitriding in order to improve its fatigue resistance, which unexpectedly reduces the steam oxidation resistance. On the other hand, significant fluctuation of valve inner wall temperature during operation accelerated the exfoliation of oxide scales, and the absence of full stroke test induced the gradual accumulation of scales in valve clearances. In light of the steam valve jam mechanism in the present case, treatments in aspects of operation and resistance to steam oxidation are recommended.
Development of High Creep Resistant 9%Cr MarBN Steels for Forgings in Advanced Steam Turbines up to 650 °C
Authors: Zeiler Guenter , Plesiutschnig Ernst
Published: March 2024

Approximately 75% of the worldwide energy supply is based on fossil energy but the discussions on CO2 emission require improvements of the conventional power technologies and also an increase of renewable energy resources. Over the past 40 years, enormous efforts, especially in the development of new materials, were made to establish the technology for the ultra-supercritical power plants, which are the standard of today’s power generation. For decades voestalpine Boehler Special Steel has been a full package supplier of customized high quality special steels and forgings with close relationships to plant manufacturers to provide products ahead of their time. This paper reports on improvements and research activities of the currently best available martensitic 9% Cr steel FB2 and the latest generation, the so-called MarBN steels, raising the operating temperatures of the 9% Cr steel class from 620 °C to 650 °C. Increasing the operating temperature requires adaptations in processes and manufacturing methods to adjust optimized microstructures with improved toughness properties and increased creep rupture strength at the same time. The microstructure of two Boron containing 9% Cr steels, FB2-2 and NPM1, developed within the framework of COST / KMM-VIN, have been investigated comparatively after different heat treatments and discussed after creep rupture tests at 650°C. The results show a dependency of the creep rupture strength on the stability of precipitates and the creep rupture time of both steels was increased by more than 30 % without negatively affecting the creep rupture strain and impact values.
Changes in Electrochemical Polarization Characteristics of High Chromium Steels by Thermal Aging Treatment
Authors: Watanabe Yasuaki , Yamashita Mitsuo , Izumi Sakae , Wang Zihao , Shoji Tetsuo
Published: March 2024

The nucleation and growth of precipitates such as Laves phases, carbides and nitrides reduce fracture toughness and high-temperature strength of high chromium steels used in thermal power plants. For this reason, to ensure a long-term plant reliability, it is important to estimate material deterioration by aging. The study presented in this paper involves micro structural evolution by thermal aging of COST-E, F, and FB2 steels, all turbine materials. The results indicate that the Laves phases and other precipitates can be separately detected and quantified by the electrochemical technique. The results also clarify the correlation between the amount of Laves phases precipitated and electrochemical polarization parameters.
Low Cycle Fatigue Properties and Impact Toughness of Advanced 10% Cr Steel with High Boron and Low Nitrogen Contents
Authors: Mishnev Roman , Dudova Nadezhda , Kaibyshev Rustam
Published: March 2024

9-12%Cr martensitic steels can be applied to the next highest temperature components such as boiler tracts, steam pipelines and turbines of advanced ultra-supercritical power plants with steam temperatures of 650°C. New 10%Cr martensitic steels with high B and low N contents can be a worthy candidate for use in production because it has superior creep resistance. At the same time, resistance to cyclic and dynamic loads is very important. In this work, we studied the low cycle fatigue (LCF) properties at room and elevated (500-650°C) temperatures and Charpy impact toughness at temperatures ranging from -196…100°C of advanced 10% Cr martensitic steel with high B and low N contents. The effect of new alloying scheme and corresponding peculiarities of M23C6 carbides on the low cycle fatigue resistance and impact toughness of the 10%Cr martensitic steel is analyzed. It is revealed that fine and densely distributed carbides has no effect on the fatigue resistance except for the slight improvement of fatigue life at small strain amplitudes and shift the ductile-brittle transition temperature (DBTT) to higher but satisfactory value of +10°C as compared to other high-chromium martensitic steels.
Comparison of Conventional, Accelerated, and Small Punch Creep Test Results in Dissimilar Weld Joints of FB2 and F Steels
Authors: Kasl Josef , Jandová Dagmar , Mandziej Stan T. , Kuboň Zdeněk
Published: March 2024

A trial weld joint of COST F and COST FB2 steels was produced using the GTAW HOT-WIRE method in conditions used in industry for production of welding steam turbine rotors. Conventional long-term creep tests (CCT) to the rupture of this weldment and the base materials were carried out at temperatures ranging from 550 °C to 650 °C in the stress range from 70 to 220 MPa (the longest time to rupture was above 52,000 hours). Creep rupture strength was evaluated using Larson-Miller parameter model. Assessment of microstructure was correlated with the creep strength. Precipitation of Laves phase and structure recovery during creep exposures were the main reasons for the failure which occurred in the heat affected zone of steel COST F. The recently developed simulative accelerated creep testing (ACT) on thermal-mechanical simulator allows the microstructural transformation of creep-resisting materials in a relatively short time to a state resembling that of multiyear application under creep conditions. ACT of samples machined from various positions in the weldment was performed at 600 °C under 100 MPa. Changes in the hardness and the microstructures of the samples, which underwent both types of creep tests, were compared. Small sample creep test (SPCT), another alternative method how to obtain information about the creep properties of materials when only a limited amount of test material is at disposal, were performed. It was shown that the same stress-temperature dependence and relationships are valid in the SPCT as in the CCT. Using a simple load-based conversion factor between the SPCT test and the CCT test with the same time to rupture, the results of both test types can be unified.
Heat-Resistant Fe-Al-Ni Based Alloys with NiAl Precipitates
Authors: Yasuda Hiroyuki Y. , Cho Ken , Edahiro Taisuke , Ikeda Kenshi
Published: March 2024

NiAl precipitates with the B2 structure are known to be effective in increasing the strength of ferritic heat-resistant steels. The strengthening mechanism by the NiAl precipitates was examined using Fe-21Al-2Ni and Fe-23Al-6Ni (at%) single crystals. As a result, the difference in primary slip system between the bcc matrix and the NiAl precipitates is responsible for strong hardening. The B2-NiAl phase was precipitated in the bcc matrix satisfying the cube-on-cube orientation relationship with small misfit strain. The primary slip direction of the bcc matrix and the NiAl precipitates are <111> and <001>, respectively. However, in the ferritic alloys, the NiAl precipitates were cut by paired 1/2<111> dislocations in the bcc matrix, resulting in the hardening. The size and volume fraction of the NiAl precipitates strongly influenced the strength. The stress increase by the NiAl precipitates was also discussed quantitatively based on the precipitation hardening theory. Based on the experimental results obtained by the single crystal study, we developed Fe-Al-Ni-Cr-Mo ferritic heat-resistant alloy containing the NiAl precipitates. The alloy exhibited excellent creep properties at 923 K.
Creep Behavior of Commercially Pure Titanium at Low and Intermediate Temperatures
Authors: Matsunaga T. , Hongo H. , Tabuchi M. , Yamabe-Mitarai Y. , Ito T.
Published: March 2024

Titanium is extensively utilized in the aerospace industry due to its low density and excellent mechanical and chemical properties. Given that components in this sector are exposed to temperatures up to 873 K, representing 45% of the metal's melting point, understanding the mechanical properties in this temperature range is crucial for ensuring flight safety. This study focuses on examining the creep behavior of pure titanium to gain insights into its fundamental mechanical response. Creep was observed to occur at stresses exceeding micro-yielding levels around 297 K, primarily attributed to overcoming the pinning effect caused by interstitial atoms. Interestingly, at intermediate temperatures, an inverted primary creep phenomenon was noted, with an activation energy of approximately 240 kJ/mol within this range. This value, significantly larger than those associated with lattice or dislocation-core diffusions, suggests the potential movement of dislocations with interstitial atoms, similar to the diffusion of oxygen or nitrogen within titanium. Moreover, fracture strain exceeded 80% at temperatures surpassing 673 K, possibly resulting from grain boundary diffusion mechanisms akin to superplasticity. The activation energy for this mechanism, at 97 kJ/mol, is adequate for activating grain boundary deformation at intermediate temperatures.
Update on United States Advanced Ultra-Supercritical Component Test Project for 760 °C Steam Conditions
Authors: Hack Horst , Purgert Robert , Schrecengost Robert
Published: March 2024

Following the successful completion of a 15-year effort to develop and test materials that would allow advanced ultra-supercritical (A-USC) coal-fired power plants to be operated at steam temperatures up to 760°C, a United States-based consortium has been working on a project (AUSC ComTest) to help achieve technical readiness to allow the construction of a commercial scale A-USC demonstration power plant. Among the goals of the ComTest project are to validate that components made from the advanced alloys can be designed and fabricated to perform under A-USC conditions, to accelerate the development of a U.S.-based supply chain for key A-USC components, and to decrease the uncertainty for cost estimates of future commercial-scale A-USC power plants. This project is intended to bring A-USC technology to the commercial scale demonstration level of readiness by completing the manufacturing R&D of A-USC components by fabricating commercial scale nickel-based alloy components and sub-assemblies that would be needed in a coal fired power plant of approximately 800 megawatts (MWe) generation capacity operating at a steam temperature of 760°C (1400°F) and steam pressure of at least 238 bar (3500 psia).The A-USC ComTest project scope includes fabrication of full scale superheater / reheater components and subassemblies (including tubes and headers), furnace membrane walls, steam turbine forged rotor, steam turbine nozzle carrier casting, and high temperature steam transfer piping. Materials of construction include Inconel 740H and Haynes 282 alloys for the high temperature sections. The project team will also conduct testing and seek to obtain ASME Code Stamp approval for nickel-based alloy pressure relief valve designs that would be used in A-USC power plants up to approximately 800 MWe size. The U.S. consortium, principally funded by the U.S. Department of Energy and the Ohio Coal Development Office under a prime contract with the Energy Industries of Ohio, with co-funding from the power industry participants, General Electric, and the Electric Power Research Institute, has completed the detailed engineering phase of the A-USC ComTest project, and is currently engaged in the procurement and fabrication phase of the work. This paper will outline the motivation for the effort, summarize work completed to date, and detail future plans for the remainder of the A-USC ComTest project.
A Evolução da Proteção ao Whistleblower na Legislação Brasileira e sua Importância no Combate a Corrupção
Authors: Xavier de Barros Martins Mário Inácio , Moro Sergio Fernando
Published: March 2024

Analisar a evolução da figura do whistleblower na legislação brasileira e sua proteção legal, bem como sua contribuição no combate a corrupção. Pesquisa teórico-bibliográfica e documental, estudo das questões debatidas ocorreu mediante consulta a livros, artigos científicos em revistas estratificadas. O whistleblower, que em tradução literal significa assoprador de apito, é o responsável pela maioria das descobertas dos casos de corrupção, portanto merece proteção legal. Nos Estados Unidos, maior economia do mundo, a proteção legal ao whistleblower surgiu após a descoberta de grandes casos de corrupção. Já no Brasil, a proteção ao whistleblower foi incluída no pacote anticrime, que prevê algumas proteções ao whistleblower, como proibição de dispensa arbitrária, inclusive com a previsão de recompensa de 5% (cinco) por cento dos valores recuperados. Identificou-se ainda que as investigações da lava jato, maior operação de combate a corrupção do Brasil, iniciou através da denuncia de um whistleblower. Permitindo observar na prática a importância do whistleblower no combate a corrupção e a necessidade de proteção legal deste. Os autores buscam observar de que forma o whistleblower contribui para o combate a corrupção, e a necessidade da edição de leis para a proteção dessa prática.
Detecção de Indícios Econômicos de Cartel na Revenda de Gás Liquefeito de Petróleo (GLP), em Goiânia - GO
Authors: Fernandes Rosangela Aparecida Soares , Bispo de Jesus Junior Leonardo
Published: March 2024

O objetivo deste artigo foi analisar os indícios econômicos de cartel na revenda de GLP, em Goiânia-GO, de maio de 2004 a junho de 2020. Utilizou-se o filtro da Agência Nacional de Petróleo, Gás Natural e Biocombustíveis (ANP); a Correlação Local Gaussiana; um modelo de volatilidade de preços; e o Modelo de Correção de Erros (MCE). O resultado do filtro da ANP indicou existência de indícios econômicos de cartel. A correlação local sugeriu que essa hipótese foi aceita para pequenos intervalos de tempo. O modelo de volatilidade indicou aumento no preço médio de revenda de GLP, durante o período de conluio. Os resultados do MCE evidenciaram indícios econômicos de cartel, no curto prazo. A instabilidade dos cartéis pode justificar, pelo menos parcialmente, esses resultados, pois, alguns acordos prevalecem durante intervalos muito pequenos e, os que existem por períodos prolongados, geralmente, praticam guerra de preços como retaliação à não cooperação.
Dampak Penyederhanaan Perizinan Lingkungan yang diatur oleh Undang-Undang No 11 Tahun 2020 Tentang Cipta Kerja Terhadap Lingkungan Hidup Masyarakat Serta Pelaku Usaha
Authors: Yuniardi Ricky , Suharyanto Yoyok , Satory Agus
Published: March 2024

Sebagai hukum administrasi dengan sifatnya yang instrumental, maka fungsi yang menonjol dalam hukum lingkungan administratif adalah bersifat preventif berupa pencegahan terhadap pencemaran dan/atau kerusakan lingkungan. Dalam Pasal 13 ayat (1) Undang-Undang Nomor 32 Tahun 2009 tentang Perlindungan dan Pengelolaan Lingkungan Hidup (UU PPLH) disebutkan bahwa Pasal 13 ayat 1 Pengendalian pencemaran dan/atau kerusakan lingkungan hidup dilaksanakan dalam rangka pelestarian fungsi lingkungan hidup. Sejak diterbitkannya Undang-undang Nomor 11 Tahun 2020, ruang lingkup dalam perizinan lingkungan sangatlah berbeda misalnya saja berdasarkan ketentuan lama, izin lingkungan terpisah dari Perizinan Berusaha, maka apabila ada pelanggaran dan dikenakan sanksi pencabutan izin, yang dicabut hanya izin lingkungan, izin usah tetap jalan.  Namun, di UU Cipta Kerja, izin lingkungan terintegrasi dengan perizinan berusaha, apabila ada pelanggaran dan dikenakan sanksi pencabutan izin, yang dicabut sekaligus Perizinan Berusaha. Hal ini sangatlah berdampak bagi masyarakat juga para pelaku usaha dibidang yang keterkaitan dengan perizinan lingkungan.
Design of Arduino-based LPG Gas Leak Detection Tool using MQ-6 Sensor
Authors: Pamungkas Diaz Resnu , Setiawan Agus , Widiyanto Andi
Published: March 2024

LPG (Liquefied Petroleum Gas) is a natural resource that has increased yearly consumption. LPG gas is used almost every time for human life in the household and industry sectors. LPG gas, besides being cheap, is also easier to use. However, the increasing use of LPG gas also increases the risk of fire or gas collection caused by LPG gas leaks. Therefore, a tool is needed to detect LPG gas leaks. So an LPG gas leak detector was made using the MQ-6 sensor, which can detect LPG gas leaks, and using a blower fan to overcome the collection of gas levels around LPG gas cylinders, using a buzzer as an alarm, using a servo to turn off the electricity so that an explosion does not occur, and use spray foam to spray onto the tube and stove if the blower cannot handle the LPG gas leak. Overall, the design components are controlled by Arduino Uno R3. This testing process takes an average of 9.56 seconds. If it is less than 9.56 seconds, then only one action is enough: the blower fan, active buzzer, and pump 1. If it is more than 9.56 seconds, the second action will be continued: spraying foam and turning off the electricity. On the other hand, there is an opportunity to bring this tool to commercial. Many households need this tool to save their house from fire threats. Finally, this tool can be a development tool for solving an incident from gas and will be a best-selling tool.
Do Business Growth and Technology Maximation Help SMEs Sustainability under Uncertainty?
Authors: Tai Do Anh , Ratnawati Ilma , Hong Nguyen Bich
Published: March 2024

This research is motivated by the large number of developments in digital start-ups and large digital-based companies that are starting to understand customers. This research aims to analyze Customer Journey Mapping (CJM) and examine what instruments are involved in digital-based start-up companies to finally develop a process model for CJM in digital-based start-up businesses. This study uses the qualitative case study method on digital-based start-up companies in Magelang and Yogyakarta, Indonesia by conducting in-depth interviews with 5 start-up owners/CEOs. The results of this research show that CJM has three stages that customers will go through and the company will respond to. In the form of prepurchase, purchase, and post-purchase stages, all stages simultaneously relate to creating a unique experience. For practical implication, this model can be maximized in start-up businesses to acquire loyal customers.
OPTIMIZATION OF DICLOFENAC POTASSIUM TRANSDERMAL PATCH FORMULA USING A COMBINATION OF POLYVYNIL PYRROLIDONE K 30, ETHYL CELLULOSE AND MENTHOL WITH SIMPLEX LATTICE DESIGN METHOD
Authors: Gunawan Sahrul , Supriyadi Supriyadi , Kuncahyo Ilham
Published: March 2024

Diclofenac potassium is one of the NSAID drugs which can cause gastrointestinal irritation and damage to the small intestinal mucosa including erosion and ulceration. The purpose of this study was to determine the effect of the combination of PVP K 30, ethyl cellulose and menthol on organoleptic, thickness, weight uniformity, moisture and folding resistance of diclofenac potassium transdermal patch.This research is an experimental study that includes an experiment to optimize the formulation of a transdermal patch preparation with the active ingredient potassium diclofenac and a combination of PVP K 30, ethyl cellulose and menthol. The optimization method uses the simplex lattice design method. There are 13 formula designs consisting of a combination of PVP K 30, ethyl cellulose and menthol. Each formula was tested for organoleptic, thickness, weight uniformity, moisture and folding resistance. Then the optimum formula was determined and analyzed using the simplex lattice design method. The combination of PVP K 30, ethyl cellulose and menthol with a simplex lattice design has an effect on the transdermal patch of diclofenac potassium which increases the consistency of the patch surface, reduces the thickness directly proportional to the weight of the patch and increases folding resistance. The proportion of PVP K 30, ethyl cellulose and menthol that can produce the optimum formula for diclofenac potassium transdermal patches with the simplex lattice design on the critical parameters of thickness, moisture, folding resistance and penetration tests, namely PVP K 30 of 14.87%, ethyl cellulose of 10.00% and 5.13% menthol.
EFFECT OF USING A RELAXATION SPLINT ON REDUCING CHRONIC NECK PAIN
Authors: Tereshchuk O.H.
Published: March 2024

Background: Approximately 80% of patients seeking dental care exhibit parafunctional manifestations of the temporomandibular joint (TMJ), while approximately 70% of patients with TMJ dysfunction experience pain in the cervical spine. It is noteworthy that neck pain is a socially significant phenomenon, as this condition can lead to a substantial decline in the patient's quality of life and disability.

Aim: To determine the effect of using a relaxation mouthguard in patients with TMJ dysfunction on reducing chronic neck pain.

Materials and methods: The study involved 16 individuals with manifestations of TMJ dysfunction, who were divided into 2 groups. The diagnosis was based on a questionnaire following the research diagnostic criteria for TMD, VAS, and the Oswestry cervical scale. Questionnaires and other examinations were conducted on all patients four times (before treatment, on days 8, 15, and 23 after treatment). Cervical spine mobility was assessed in all patients, and mandibular axiography was performed. Patients in the experimental group, comprising 8 individuals, were fitted with individual relaxation splints and prescribed manual massage of the masticatory and cervical muscles. Patients in the control group, also consisting of 8 patients, were instructed to perform manual massage of the masticatory and cervical muscles.

Results: Patients in both study groups demonstrated a reduction in clinical symptoms. According to the study data, the reduction of pain in the experimental group from the beginning to the end of treatment was 62.86% (p < 0.001) of the initial value, whereas in the control group, it was 13.75% (p < 0.001). There was an increase in mobility of the cervical spine in both study groups (p < 0.001). The index of cervical spine disability in the experimental group improved by 225% compared to the control group.

Conclusions: The use of a relaxation mouthguard in patients with TMJ dysfunction and existing neck pain symptoms can alleviate chronic pain manifestations in the cervical spine.
CLINICAL STATE OF DIRECT RESTORATION OF SIDE TEETH IN ORTHODONTIC PATIENTS
Authors: Udod O.A. , Dramaretska S.I.
Published: March 2024

Relevance. During long-term orthodontic treatment, there are favorable conditions for the development of dental caries and periodontal diseases.

Aim of the study. Retrospective clinical evaluation of direct restorations of teeth in patients during treatment of orthodontic pathology with fixed appliances.

Materials and methods. The condition of 227 direct photocomposite restorations of lateral teeth with localization on the occlusal and one of the contact surfaces and duration of functioning from 1 to 5 years was studied in 57 people who were treated with the use of fixed orthodontic equipment. Marginal fit, secondary caries and contact points were evaluated.

Research results. In restorations with terms of 1-2 years, a violation of the marginal fit on the occlusal surface was found in 5 restorations (6.4% of their number with the given terms), on the vestibular and oral surfaces – in 7 (9%), in the area near the gums – in 10 restorations (12.8%). Secondary caries was detected on the vestibular surface in 2 restored teeth (2.6%), in the area near the gums – in 8 teeth (10.3%). There were violations of the contact point in 4 cases (5.1%). With terms of 4-5 years, in 3 restorations (10.3% of the number with these terms), violations of marginal fit were established on the occlusal surface, in 9 (31%) on the vestibular and oral surfaces, in 17 restorations (58.6%) – in the area near the gums. Secondary caries on the occlusal surface was found in 2 teeth (6.9%), on the vestibular and oral surfaces in 4 (13.8%), in the area near the gums – in 16 teeth (55.2%). Defects of the contact point were established in 19 cases (65.5%). Conclusions. In the conditions of orthodontic treatment with fixed equipment, the risk of developing disorders in photocomposite restorations in the area near the gums of the contact surfaces of the lateral teeth increases significantly.
Decomposition of 138 galaxies at 0.1 < z < 2.2 with spiral structure
Authors:   The Central Astronomical Observatory of the RAS at Pulkovo, Chugunov I.V. , Marchuk A.A. ,   The Central Astronomical Observatory of the RAS at Pulkovo,   Saint Petersburg State University
Published: March 2024

Various problems concerning the origin and evolution of spiral arms in galaxies are still remain unsettled. Also, only few studies are devoted to the parameters of the spiral structure in distant galaxies. To investigate this, we have performed decomposition with spiral arms of 138 distant galaxies from COSMOS and CEERS surveys, located at redshift 0.1 < z < 2.2 (up to 10.5 Gyr ago). For all 9 galaxies from CEERS, multi-band images are utilized. As a result, different parameters dependence on redshift and wavelength are studied. In particular, we confirm that pitch angle of spiral arms increases with redshift. For the spiral arm width, we find relationship with redshift, but this value depends much stronger on wavelength. A
ÇLİ KÖMÜR STOKLARINDA KALORİ HOMOJENİZASYON VERİMLİLİĞİNİN İNCELENMESİ
Authors: Çelik Arif
Published: March 2024

Dünya genelinde yaşanan küresel enflasyon ve Rusya-Ukrayna savaşının neden olduğu enerji krizi tüm dünyada enerji verimliliği ile ilgili çalışmaların ivme kazanmasına olanak sağlamıştır. Kömüre dayalı termik santrallerdeki enerji üretim verimliliği de bu çalışmaların önemlilerindendir. Bilindiği üzere kömüre dayalı termik santrallerde enerji verimliliği hususunda en önemli parametrelerden biri termik santralin kazan dizaynına uygun özelliklerdeki kömürlerin teminidir. Burada, benzer özelliklerdeki kömürlerin yüksek miktarlarda sürekli teminini sağlamak kolay bir süreç olmadığından dolayı, uygulamada farklı özelliklerdeki kömürler stok sahalarında harmanlama/homojenizasyon uygulamaları ile biraya getirilmekte ve istenilen özelliklerdeki kömür hazırlanmaya çalışılmaktadır. Bu çalışmada, iki termik santral için farklı özelliklerde kömür temin eden Çan Linyitleri İşletmesinde (ÇLİ) uygulanan homojenizasyon faaliyetleri araştırılmış ve bu faaliyetlerin verimliliği değerlendirilmiştir. Araştırma sonuçları, ÇLİ’de uygulanan homojenizasyon tekniğinin iki termik santral için ortalama %77,9 oranında başarı gösterdiğini ortaya koymuştur. Araştırma sonuçlarına paralel olarak, çalışma kapsamında, mevcut homojenizasyon yönteminin verimliliğini daha üst seviyelere çıkarabilecek değişiklik önerisi yapılmıştır.
GRAFİT TOZUNUN KAUÇUK KARIŞIMLARIN ÜZERİNE ETKİLERİNİN İNCELENMESİ
Authors: Erbek Cömez Ezgi , Hoşgün Halit Levent , Öztürk Selda
Published: March 2024

Kauçuk ürünler vulkanizasyonun keşfedilmesiyle beraber günümüzde farklı alanlarda sıkça kullanılmaya başlanmıştır. Bu ürünler beyaz eşya, otomotiv, uçak ve roket sanayi, inşaat ve demir yolu gibi sektörlerde değerli yere sahiptirler. Kauçuk ürünlerin fazla kullanımı kauçuk çeşitliliğinin önemini de arttırmaktadır. Her kauçuk tipinin kendine has özellikleri bulunmaktadır ve kullanım yerlerine göre özel katkı malzemeleri ilaveleriyle bu özellikler daha da geliştirilebilmektedirler. Etilen Propilen Dien Monomer (EPDM) kauçuğu kendine has özelliklerinden dolayı tercih edilen kauçuklar arasındadır ve özel katkı malzemeleri kullanılarak yetersiz yönlerinin geliştirilebilmesi mümkün bir kauçuk türüdür. Bu çalışmanın amacı EPDM kauçuğu kullanılarak oluşturulmuş EPDM karışımına toz grafit katkı malzemesinin ilavesi ile mekanik özelliklerine etkisinin incelenmesidir. Bunun için çalışma kapsamında iki farklı türde kauçuk karışımları oluşturulmuştur. Karışım reçetelerine özel katkı malzemesi olarak toz grafit (EPDM GP) 10 phr oranında eklenmiş, saf karışım reçetesiyle (EPDM 0) reolojik ve mekanik değerleri karşılaştırılmıştır. Kauçuk karışımlarının reolojik değerleri, viskoziteleri, sertlikleri, modül değerleri, kopma mukavemetleri, uzama miktarları, yoğunlukları, külleri, yanma davranışları ve çapraz bağ yoğunlukları analiz edilmiştir. Grafit katkısının kauçuğun mekanik değerlerine olumlu etki ettiği belirlenmiştir. Grafitin karışıma katılmasıyla kauçuk karışımın yanma eğiliminin arttırdığı görülmektedir. Bununla birlikte kauçuk karışıma grafitin eklenmesi çapraz bağ yoğunluklarını (CLD) da arttırmaktadır.
KRİYOJENİK ISIL İŞLEMİN Ti6Al4V ALAŞIMINLARINDA DİNAMİK TOKLUK ÜZERİNDEKİ ETKİSİNİN DENEYSEL ARAŞTIRILMASI
Authors: Çimen Cansu , Kılıçay Koray , Kaya Esad
Published: March 2024

Ti6Al4V alaşımlarının mekanik ve mikroyapı özelliklerinin iyileştirilmesi konusunda çeşitli ısıl işlemler vardır. Bu ısıl işlemlerden biri de kriyojenik ısıl işlemdir. Kriyojenik işlem, malzemenin -196°C’ye kademeli soğutulup, bekletilerek ve sonrasında kademeli ısıtılarak uygulanan bir ısıl işlemdir. Son yıllarda gelişen teknoloji ile metallerin mikro yapısını ve mekanik özelliklerini iyileştirmek için tamamlayıcı bir proses olarak kullanılmaktadır. Bu çalışmada Ti6Al4V alaşımlarına farklı bekletme sürelerinde uygulanan kriyojenik ısıl işlemin dinamik tokluk ve mikroyapısal özellikler üzerindeki etkisi incelenmiştir. Kriyojenik ısıl işlemler 12, 24 ve 36 saat olacak şekilde yapılmıştır. Numunelerin oda sıcaklığında dinamik tokluk değerini gözlemleyebilmek için Charpy çentikli darbe testi yapılmıştır. Deneysel çalışmaların neticesinde Ti6Al4V alaşımına uygulanan kriyojenik ısıl işlemin tokluk değeri üzerinde olumlu etkisi olduğu gözlemlenmiş, 36 saat kriyojenik işlem uygulanan numunenin dinamik tokluğunun işlemsiz numuneye göre %28 arttığı ve en efektif bekletme süresi olduğu görülmüştür. Ayrıca kriyojenik işlemin etkilerini belirlemek için mikro yapı incelemeleri ve mikrosertlik testi yapılmıştır. Mikroyapı üzerinde ise süre koşuluna bağlı olarak β fazının α fazına dönüşmesiyle yapıdaki iç gerilmelerin azaldığı ve daha kararlı bir yapıya dönüştüğü gözlemlenmiştir. Kriyojenik ısıl işlemin sıcaklık ve süre kontrollü uygulanmasının malzemenin mekanik ve mikroyapısal özelliklerini olumlu yönde etkilediği gözlemlenmiştir.
Analisis Perbuatan Mengalihkan dan Merusak Cagar Budaya (Studi Kasus Cagar Budaya Benteng Putri Hijau Di Delitua)
Authors: Stepya Chorry , Ginting Lilawati
Published: March 2024

Protection of cultural heritage in Indonesia is regulated in Law no. 11 of 2010 concerning Cultural Heritage. Violations in the form of destroying cultural heritage can be subject to serious criminal sanctions. One example of a protected cultural heritage is Fort Putri Hijau, with various protection efforts by the government such as restoration, monitoring and outreach, in order to preserve this historic site as the nation's cultural heritage.
Perlindungan Hukum Terhadap Kerugian Konsumen Atas Wanprestasi Pelaku Usaha Jasa Titip Beli Barang Secara Online
Authors: Pratiwi Tiara , Syuhada Lubis Mhd. Teguh
Published: March 2024

This research is aimed at finding out the legal protection given to consumers for the performance of the entrepreneur of services to buy goods online contained in article 4 of the Act No. 8 Year 1999 where there are many cases of fraud such as uncertainty of the quality of the goods purchased because of the fact that they cannot see them in person. Sometimes goods purchased are not as expected and there is a risk of fraud, where the goods already purchased did not arrive or differ from the one ordered. Not all online sellers are reliable, and often there are cases of frauds in which consumers have transferred money but the ordered goods do not arrive. The type of research used is normative legal research, which is obtained from library materials or secondary data.
PENGARUH KUALITAS PELAYANAN, SERVICESCAPE DAN BRAND IMAGE TERHADAP KEPUASAN KONSUMEN PADA BURGER BANGOR SIDOARJO
Authors: Muzakqi Mochammad Rifqian , Zaki Achmad
Published: March 2024

Kepuasan konsumen dalam beberapa faktor dapat mempengaruhi hal-hal tersebut yang mencakup kualitas dari layanan yang diberikan, layanancape dan citra merek. Melalui penelitian ini, bertujuan untuk mengamati kepuasan konsumen burger bangor Sidoarjo. Penelitian ini menerapkan pendekatan kuantitatif asosiatif. Populasi pada penelitian ini tidak diketahui. Sedangkan sampel yang dipakai menggunakan rumus slovin sebanyak 108 responden yang diperoleh menggunakan metode Purposive Sampling . Data diperoleh dari penyebaran kuesioner dengan google form yang berisi beberapa pernyataan dengan skala likert. Instrumen juga akan di uji dengan uji validitas serta reliabilitas. Data yang diperoleh dianalisis dengan metode IBM SPSS 24 dengan beberapa tahapan pengujian yaitu uji normalitas, multikolineritas, heterokedastisitas, analisis regresi linier berganda dan signifikasi parsial (Uji-T). Hasil penelitian menemukan bahwa kualitas pelayanan mempunyai pengaruh sebagian terhadap kepuasan konsumen, pelayanancape memberikan pengaruh sebagian terhadap kepuasan konsumen serta citra merek memberikan pengaruh sebagian terhadap kepuasan konsumen.
Widerspruch schafft Erkenntnis. Das Interview von Waltraud Schwab (taz, die tageszeitung) mit dem Historiker Michael Wolffsohn über den Nahostkonflikt
Authors: Schwab Waltraud
Published: March 2024

Professor Michael Wolffsohn spricht mit Waltraud Schwab von der Tageszeitung taz über die neue Gewaltdimenson des 7. Oktobers 2023, dessen Auswirkungen auf das Leben von Jüdinnen und Juden und die Vielschichtigkeit des Nahostkonflikts.
Deutschland – der „kranke Mann Europas“?
Authors: van Scherpenberg Jens
Published: March 2024

Die Schlagzeile von Deutschland als ‚krankem Mann Europas‘ hat Konjunktur. Jens van Scherpenberg fragt sich: Was ist dran am deutschen wirtschaftlichen Niedergang? Geht er erst richtig los, ist er schon vorbei, bevor er überhaupt begonnen hat? Oder steckt hinter dem Reden vom Niedergang Deutschlands womöglich einfach der Anspruch der europäischen Führungsmacht auf ungebrochenen Erfolg, an dem gemessen die gegenwärtige Wachstumsschwäche als nationale Katastrophe erscheint?
On Some Properties of Maximal Prefix Codes and Machine Learning for Automata
Authors: Krainiukov Nikolai , Abramyan Mikhail , Melnikov Boris
Published: March 2024

In this paper we study the prefix codes and application of prefix codes for problem of machine learning for deterministic finite state automaton. We give an example for the problem of constructing an inverse morphism, also parameterized by the number of transitions of automata. We investigate the factorization of prefix codes can give more simple structure of DFA for understanding his behaviors. To verify the correctness of the proposed approach, we implemented a system computer algebra GAP that accurately performs the logical flow of algorithm cycle by cycle.