bluuebunny/crossref_metadata_2025 huggingface dataset:
A study on the individual pump flow estimation processor for optimal operation
Authors: Rakibuzzaman Md , Suh Sang-Ho , Yoon In-Sik , Jung Sang Yong
Published: November 2021

The booster pump is an energy-saving system that controls the number of turns of the pump and optimal operation by installing an inverter to control the discharge pressure of the pump in accordance with the flow rate. The development of an optimum operation algorithm and flow rate information for the individual pumps without flow sensors is critical of a smart booster pump system. The objectives of this study was to investigate the algorithm based flow detection method without use of a flow sensor for each pump. Therefore, it was developed an algorithm-based flow rate detection method of individual pumps without the use of a flow sensor that has not been studied in the conventional booster pump system. The software-based processor development and experimental verification for detecting the flow rate of individual pumps were confirmed. The ensemble error was within 2%. For optimal operation, the result of examining the accumulated flow rate for the sequential operation method and the optimum operation method. The flow measurement accuracy of the system was confirmed by experiment and the development of a booster pump system without a flow sensor was found effective.
Distribution of flying fish species (Exocoetidae) in the waters of Ambon Island
Authors: Tuapetel Friesland , Tupan Charlotha
Published: November 2021

There are 71 species of flying fish (exocoetidae) in the world, 18 species in Indonesia, and ten species in Maluku. The southern waters of Ambon Island are potential areas for catching flying fish, but the species distribution has not been reported. This study aimed to determine the composition and distribution of flying fish species caught by gillnet in the southern Ambon Island waters. The study of flying fish species was carried out from February to June 2021. There were five dominant flying fish species distributed consistently based on their respective zones. The morphological identification revealed flying fish species which broadcast on the coast of the island respectively, namely:Cypselurus poecilopterus,Cheilopogon abei,Cheilopogon spilopteruswith geographical position - 3°73′07″S – -3°92′01″S and 128°15′04″E – 128°44′08″E. The high seas were dominated byCheilopogon furcatusdanHirundichthys oxycephaluswith position -4°14′08″S – -4°72′16″S and 128°28′05″E – 129°42′09″E. This information could be provided as a database for the management and sustainable use of flying fish resources to support Indonesia's National Fish Reserve or Lumbung Ikan Nasional (LIN).
Status of water quality and level of trophic in Juanda Reservoir of Purwakarta Regency, West Java, Indonesia
Authors: Jubaedah Iis , Anas Pigoselpi , Ruchimat Toni , Haryadi Joni
Published: November 2021

Juanda reservoir is one of the reservoirs located in Purwakarta Regency, West Java Province, Indonesia, whose primary function is hydropower, water resources for irrigation, industrial and drinking water, and secondary function for fisheries and tourism activities. Currently, an increase in activities around the existing reservoir has affected its water quality. In order to determine the water quality and trophic level status of the Juanda reservoir, research has been conducted within five stations during the period of August-December 2020. The water quality status includes physical, chemical, and biological parameters that compared with Store standards on Class II and III. Meanwhile, the trophic status was determined by Trophic Level Index (TLI) based on the parameters of transparency, chlorophyll-a, total nitrogen, and total phosphorus. The results show that the water quality status of Juanda reservoir has been contaminated Class III and heavily polluted Class II. The parameters that exceed include ammonia, nitrate, and BOD5. The Juanda reservoir's tropic status was in the eutrophic category, with TLI values ranging from 4.6 to 5.2.
Fish fauna of peatland waters in the middle Mahakam, Kutai Kartanegara, East Kalimantan, Indonesia
Authors: Suyatna Iwan , Sukarti Komsanah , Pagoray Henny , Kesuma Arif Data , Butarbutar Tunggul , Raafi Muhammad , Suyatna Muhammad Bagja Britania
Published: November 2021

A field study was carried out to collect fish from the lake and streams/rivers around the peatland from December 2020 to February 2021. Fishing gears such as gillnet, snakehead pole and line, lift net, trap net ("sawaran", "julu"), and fish pot ("tokong", "pangilar", "bubu" or "lukah" and "tempirai") were operated. Sampling sites, water velocities, and water depth were measured using GPS Garmin 60 CSX, current meter hydrologic velocity meter, and fishfinder Portable, respectively. Generally, water velocities of streams measured were much more rapid than the lakes ranging between 0.33 m/s (at water depth: 4.20 m) and 0,69 m/s (at water depth: 6.80 m); and "not detected" (at water depth: 2.40 m) and 0.34 m/s (at water depth: 1.20 m) respectively. Of 7,377 fish samples, there were 50 species discovered belonging to 19 families. Cyprinidae was the most populated in individuals and species as well (1,022 Ind.; 21 taxa). It was followed by Bagridae (63 Ind.; five taxa), Channidae (53 Ind.; three taxa), Clariidae (10 Ind.; three taxa), Siluridae (403 Ind.; three taxa), while other families had just one taxon. Diversity was observed higher in streams (35 species) than lakes (30 species). Local fishers are still performing unselective fishing for feeding fish cage culture.
Effects of different wavelength from Light Emitting Diodes (LEDs) on growth and development in zebrafish (Danio rerio) embryos and larvae
Authors: Septriani Shafira , Kiddane Anley Teferra , Kim Gun Do , Brown Christopher L.
Published: November 2021

A light environment in aquatic habitat is one of the essential physical parameters affecting the growth and physiology of fish. To investigate the effects of light on the growth of zebrafish embryos and larvae (Danio rerio), fishes were reared under the illumination of Light Emitting Diodes (LEDs) of different wavelengths, including green, red, blue, and white. Morphometric, neuromast staining with 2-[4-(Dimethylamino)styryl]-1-ethylpyridinium iodide (DASPEI) and Polymerase Chain Reaction (PCR) analyses were used to examine the initial development of sensory capacity in this study. On days 5, 6, and 7, the green light produced the most favorable result. Blue light consistently impacted early parameters such as eye development, egg yolk absorption, and total length. These impacts were synchronous with the initiation of feeding. Exposure to specific wavelengths of light can induce the appearance of gene expression, opn1lw1 detected opsin and (mtnr1ba and aanat2) were active under all four experimental lighting conditions. This retinal gene appears to be sensitive to ambient wavelength, but apparently, genes in the melatonin pathway are not.
Estimated production, catch per unit effort, biological aspects of tuna, skipjack, and small tuna in North Sumatra
Authors: Levi Arnenda Gussasta , Rochman Fathur , Wujdi Arief , Kurniawan Roy
Published: November 2021

Tuna and like species resources are like other renewable resources. The level of exploitation of these resources dramatically affects their ability to maintain their numbers and abundance in the water. Fishery management policy should be conducted based on a scientific-based approach. This research aims to collect data related to tuna fisheries and the like, including data collection aspects of coaching, the composition of catches, and the biology of tuna catches in 2020. Research location in North Sumatra. The results showed that the estimated value of skipjack tuna (SKJ) of 232,823 tons, yellowfin tuna (YFT) of 23,682 tons, frigate tuna (FRI) is 40,949 tons, and Kawakawa (KAW) is 1,374 tons. SKJ, as of 6.149 samples, have length class 18-60 cmFL, CPUE highest in April and lowest in August. FRI of 1.619 samples with a lengthy class between 17-44 cmFL, CPUE highest in October and lowest in December. YFT of 1.060 samples with a lengthy class 18-60 cm, CPUE highest in April and lowest in March. Kawakawa of the 1.530 samples has length class 25-54 cm, with the highest CPUE in April and lowest in March and July.
The potency of spice extracts in fish skin collagen production
Authors: Sadi Nina Hermayani , Khatami Visal , Mulyati Ade Heri
Published: November 2021

Spices can be used as an alternative washing agent in fish collagen production, replacing organic materials' commonly used washing agent. Many Asians, including Indonesian traditional culinary use spices to remove the fishy odor. Therefore this research was conducted to obtain a suitable spice used as a washing agent in fish collagen production. Ginger, galangal, lemongrass, bay leaves, lime leaves, and pandan leaves were used as the tested spices in the form of 5% liquid extract in water. The ANOVA and LSD test on fishy odor test data showed that most respondents preferred Pangasius skin soaked in galangal liquid extract and had no significant difference in odor compared to the control (ethanol). Pangasius skin soaked in galangal extract had the total protein and ash content lower than control, while the total fat and water content were higher. Soaking in galangal extract also made Pangasius skin have a higher degree in swelling and total protein content in its acid-soluble collagen (ASC) extract than in control. The higher value of the two latter parameters was also found in the descaling Tuna skin soaked in galangal extract.
Perspective plan for sustainable eel management in Lake Poso, Central Sulawesi
Authors: Triyanto  , Haryani Gadis S. , Lukman  , Wibowo Hendro , Ali Fauzan , Hidayat  , Sulawesty Fachmijany , Setiawan Foni A. , Triwisesa Endra , Dwinovantyo Angga , Riyanto Mohammad , Samir Octavianto , Nafisyah Eva
Published: November 2021

Lake Poso has high eel potential and a strategic position in supporting the development of eel fisheries in Sulawesi. Lake Poso is out of 15 national priority lakes in natural resources and environmental management programs. The catch of eel from Lake Poso is reported to have been decreasing for the last twenty years. Several factors causing the decline in eel populations are fishing activities, disruption in migration routes, and other factors such as changes in habitat and environmental conditions. The sustainability of the life of the Poso eel is determined by the success of the eel migration process. The migration of adult eels to the sea and young eels from glass eels to freshwater habitats must continue. The perspective plans that can be done to manage Poso's eel resources include 1) Socializing the eco-biological characteristics of eels as catadromous fish; 2) Establishing conservation areas and regulation of eel fishing; 3) Increasing eel population through restocking 4) Integrating fisheries and aquaculture activities; 5) Developing eel culture technology through size segmentation production; 6) Developing an eel migration monitoring system; 7) Building a cross-sectoral forum and put a joint action program; 8) Proposing the Poso eel Research and Conservation Center.
Effects of stable clearances on backflow in the variable-pitch screw vacuum pump
Authors: Zhang Li , Zhang Yongju , Chen Ziyun
Published: November 2021

Effects of various clearances of variable-pitch screw vacuum pump on gas backflow of internal flow field of the pump cavity is studied. The theoretical tooth surfaces of screw rotor are optimized by radial, normal equidistance modifications, and four types of stable clearances of rotor circumferential, radial, tooth shape and tooth sides are obtained. The backflow calculation model in clearances considering Couette backflow and orifice backflow is improved. The three-dimensional model of variable-pitch screw vacuum pump is designed, and the experimental prototype and test device are developed. The internal backflow of vacuum pump is analyzed by using the commercial software Ansys-Fluent® and the calculation model. The results show that the smaller the clearances, the smaller the backflow and the higher the vacuum degree. Among the four types of clearances, the circumferential clearance plays the primary roles. The backflow is directly proportional to the inlet pressure and rotating speed. Predictions are validated by the experimental data with satisfied agreement.
Modellhafte Register für die
Versorgungsforschung
Authors: Stausberg Jürgen
Published: November 2021

Register sind eine etablierte und bewährte Methode der Versorgungsforschung
1. Umso weitsichtiger war es vom
Bundesministerium für Bildung und Forschung (BMBF) im Jahre 2016, mit einer
Ausschreibung zum Aufbau modellhafter patientenbezogener Register für die
Versorgungsforschung die Zukunftsfähigkeit und Innovationskraft dieser
Methode zu unterstreichen (s. https://www.gesundheitsforschung-bmbf.de/de/modellhafte-register-realisierungsphase-9011.php).
Hierbei hatte das BMBF mit einer Zweiteilung der Förderung in eine
Konzepterstellung und eine Realisierung die Bedeutung der systematischen Entwicklung
eines Registers hervorgehoben und damit die Impulse aus dem Deutschen Netzwerk
Versorgungsforschung (DNVF) für ein Registerprotokoll 2 aufgenommen. Aus 16 Projekten wurden sechs
Register für eine Umsetzung ausgewählt, die sich zusammen mit einem
Begleitprojekt in diesem Sonderheft der Zeitschrift „Das
Gesundheitswesen“ präsentieren.
cis-Aconitic Acid, a Constituent of Echinodorus grandiflorus Leaves, Inhibits Antigen-Induced Arthritis and Gout in Mice
Authors: de Oliveira Diego Pinto , Garcia Eliana de Faria , de Oliveira Mariana Assíria , Candido Luiza C. M. , Coelho Fernanda M. , Costa Vivian Vasconcelos , Batista Nathália Vieira , Queiroz-Junior Celso Martins , Brito Larissa Froede , Sousa Lirlândia Pires , Souza Daniele G. , Amaral Flávio Almeida , de Pádua Rodrigo Maia , Teixeira Mauro Martins , Braga Fernão Castro
Published: November 2021

cis-Aconitic acid is a constituent from the leaves of Echinodorus grandiflorus, a medicinal plant traditionally used in Brazil to treat inflammatory conditions, including arthritic diseases. The present study aimed to investigate the anti-arthritic effect of cis-aconitic acid in murine models of antigen-induced arthritis and monosodium urate-induced gout. The possible underlying mechanisms of action was evaluated in THP-1 macrophages. Oral treatment with cis-aconitic acid (10, 30, and 90 mg/kg) reduced leukocyte accumulation in the joint cavity and C-X-C motif chemokine ligand 1 and IL-1β levels in periarticular tissue. cis-Aconitic acid treatment reduced joint inflammation in tissue sections of antigen-induced arthritis mice and these effects were associated with decreased mechanical hypernociception. Administration of cis-aconitic acid (30 mg/kg p. o.) also reduced leukocyte accumulation in the joint cavity after the
injection of monosodium urate crystals. cis-Aconitic acid reduced in vitro the release of TNF-α and phosphorylation of IκBα in lipopolysaccharide-stimulated THP-1 macrophages, suggesting that inhibition of nuclear factor kappa B activation was an underlying mechanism of cis-aconitic acid-induced anti-inflammatory effects. In conclusion, cis-aconitic acid has significant anti-inflammatory effects in antigen-induced arthritis and monosodium urate-induced arthritis in mice, suggesting its potential for the treatment of inflammatory diseases of the joint in humans. Additionally, our findings suggest that this compound may contribute to the anti-inflammatory effect previously reported for E. grandiflorus extracts.
Regioselective Amination or Alkoxylation of Halogenated Amino-, Thio- or Alkoxypyridines via Pyridyne Intermediates
Authors: Knochel Paul , Heinz Benjamin , Djukanovic Dimitrije , Siemens Fiona , Idriess Mohamed , Martin Benjamin
Published: November 2021

The treatment of 3-halopyridines (Cl, Br) bearing an R-substituent in position 2 (R = OEt, NEt2, N-piperidyl, or SEt) or in position 5 (R = OMe, OEt, SEt, NMe2, NEt2, or aryl) with KHMDS and an amine at 25 °C for 12 hours in THF provided regioselectively 3- and 4-aminated pyridines in 56–90% yields. The reaction of 3-bromo-2-diethylaminopyridine with various alcohols in the presence of t-BuOK/18-crown-6 in THF at 80 °C for 20–60 hours gave various 4-alkoxy-2-diethylaminopyridines in 61–81% yields. These substitution reactions were proposed to proceed via pyridyne intermediates.
Sobrevida em longo prazo do espaçador cimentado para quadril: Relato de caso
Authors: Jacob Roshan , Sowers Mackenzie , Chandler Kelly , Patel Mihir , Shah Ashish B. , Naranje Sameer Mahadeorao
Published: November 2021

Apresentamos um caso único de um homem de 56 anos que deambulou com um espaçador cimentado para quadril durante 11 anos. Após ser submetido a uma hemiartroplastia em virtude de um acidente de carro, o paciente desenvolveu uma infecção articular periprotética (IAP) vários anos depois, sendo submetido à técnica de revisão da etapa 1. Com a resolução da infecção depois da etapa 1, o paciente recusou a segunda etapa, devido à satisfação com o espaçador cimentado por quase 11 anos.

Pelo que sabemos, este é o caso mais longo relatado de um espaçador cimentado em um paciente deambulando. Este caso demonstra a confiabilidade mecânica dos espaçadores cimentados reforçados com metal que podem ser mantidos por um prazo longo em pacientes selecionados.
Laryngotracheomalacia in a Patient with Mosaic Trisomy 8
Authors: de Souza Mateus A. , Hartmann Jéssica K. , Zottis Laira F. F. , Gama Thiago K. K. , Rosa Ernani B. da , Zen Paulo R. G. , Rosa Rafael F. M.
Published: November 2021

Mosaic trisomy 8 is a condition characterized by a great phenotypic and cytogenetic variability whose incidence ranges around 1 in 25,000 to 50,000 live births. Here, we report a mosaic trisomy 8 patient presenting laryngotracheomalacia, an uncommon finding, analyzing its possible role over morbidity, and mortality. The patient was a boy who, after birth, had tachypnea and paleness. He presented periods of respiratory dysfunction with need of ventilatory support. Respiratory syncytial virus test was positive. Naso fibrobronchoscopy showed moderate laryngotracheomalacia. He also had recurrent episodes of pneumonia and difficulty in withdrawing continuous positive airway pressure. The patient also presented leucoma, abnormal and low-set ears, pectus excavatum, clenched fists with overlapping fingers, cryptorchidism, clubfeet, and deep longitudinal plantar creases. G-bands by Trypsin using giemsa (GTG-banding) karyotype from a peripheral blood sample revealed a mosaic trisomy 8: mos 47,XY, + 8[15]/46,XY[7]. At 4 months, the patient developed respiratory failure, and a chest computed tomography scan showed areas of atelectasis and gross fibroatelectatic striae. He ended up presenting clinical worsening and died at 4 months and 8 days. In our literature review, we found some reports describing patients with mosaic trisomy 8 and laryngotracheomalacia. However, we cannot rule out the possibility that this association could be casual, since laryngotracheomalacia is a relatively common finding in children. Therefore, more studies are still necessary to understand the possible relation between both conditions and the role of laryngotracheomalacia over morbidity and prognosis of mosaic trisomy 8 patients.
Sarcoma sinovial insidioso de osso em um paciente com artrite reumatoide
Authors: Villarreal Juan Carlos Reyes , Pineda-Galindo Luis Francisco , Vera-Lastra Olga , Quispe-Susara Elizabeth Natalia , Navarro Alberto Ordinola
Published: November 2021

Sarcoma sinovial é uma rara malignidade de origem mesenquimal; a abordagem diagnóstica geralmente começa documentando um tumor de tecido mole; no entanto, resulta em um diagnóstico desafiador quando é mais profundo, de pequeno porte ou primário do osso.

O presente relato descreve um paciente que apresentou dor insidiosa no quadril atribuída a artrite reumatoide, com desfecho fatal devido a doenças de base e complicações cirúrgicas.

A subestimação da dor no quadril, principalmente quando não há massa palpável, pode atrasar o diagnóstico.
10.1 Product Class 1: Benzo[b]furans
Authors: Kwiecień H.
Published: November 2021

This chapter is a revision of the earlier Section 10.1 in SScience of Synthesis. It describes methods for the synthesis of benzo[b]furans and related compounds such as benzo[b]furan-3(2H)- and benzo[b]furan-2(3H)-ones. Classical routes to benzo[b]furans involve intramolecular cyclizations of suitably substituted arenes, most often phenols and aryloxy carbonyl compounds and their derivatives, or intermolecular cyclization reactions based on 2-halophenols and alkynes. However, very popular metal-catalyzed developments, with various approaches, are also included. Methods for the synthesis of benzo[b]furans from furans by construction of the homocyclic aromatic ring, including homogeneous metal-catalyzed benzannulation, are also presented.
Schrödinger p⋅–Laplace equations in RN involving indefinite weights and critical growth
Authors: Ho Ky , Kim Yun-Ho , Lee Jongrak
Published: November 2021

We study a class of critical Schrödinger p⋅–Laplace equations in RN, with reaction terms of the concave–convex type and involving indefinite weights. The class of potentials used in this study is different from that in most existing studies on Schrödinger equations in RN. We establish a concentration-compactness principle for weighted Sobolev spaces with variable exponents involving the potentials. By employing this concentration-compactness principle and the Nehari manifold method, we obtain existence and multiplicity results for the solution to our problem.
Numerical study of transverse position monitor and compensation for x-ray polarization diagnosis
Authors: Liu Zipeng , Deng Bangjie , Deng Haixiao , Liu Bo
Published: November 2021

Diagnosing free electron laser (FEL) polarization is critical for polarization-modulated research such as x-ray FEL diffraction imaging and probing material magnetism. In an electron time-of-flight (eTOF) polarimeter, the flight time and angular distribution of photoelectrons were designed based on x-ray polarimetry for on-site diagnosis. However, the transverse position of x-ray FEL pulses introduces error into the measured photoelectron angular distribution. This work, thus, proposes a method of compensating transverse position jitters for the polarization by the eTOF polarimeter itself without an external x-ray beam-position monitor. A comprehensive numerical model is developed to demonstrate the feasibility of the compensation method, and the results reveal that a spatial resolution of 20 μm and a polarity improved by 0.02 are possible with fully polarized FEL pulses. The impact of FEL pulses and a method to calibrate their linearity are also discussed.
Effect of graphene domains orientation on quasi van der Waals epitaxy of GaN
Authors: Borisenko D. P. , Gusev A. S. , Kargin N. I. , Dobrokhotov P. L. , Timofeev A. A. , Labunov V. A. , Kovalchuk N. G. , Mikhalik M. M. , Komissarov I. V.
Published: November 2021

We demonstrate the growth features of III-nitrides on graphene buffer layers obtained by the CVD method on a copper catalyst with different dominant grain orientations. The reflection high-energy electron diffraction technique (RHEED) is used to map the 2D reciprocal space structures of graphene buffers and growing nitride layers. The RHEED reciprocal space pattern for the graphene layer grown on a (111) textured copper foil and transferred to a SiO2/Si substrate demonstrates the sixfold symmetry characteristic of a highly oriented material. In turn, graphene grown on a Cu (100) foil consists of two types of domains that are 30° rotated relative to each other. It has also been demonstrated that III-nitride films exactly repeat the texture of the 2D graphene buffers. The GaN sample grown over the highly textured substrate demonstrates a clear sixfold symmetry of the RHEED reciprocal space map as well as {101¯3} XRD pole figure, which is close to 2D surface morphology. In turn, the GaN film grown over the graphene buffer layer transferred from the Cu (100) textured foil has 12-fold axial symmetry, which is equivalent to the essentially two-domain in-plane orientation of the initial graphene.
Simple numerical simulation of catalyst inks dispersion in proton exchange membrane fuel cell by the lattice Boltzmann method
Authors: Li Bing , Ding Zhiqiang , Guo Yuqing , Wang Yabo , Tang Haifeng , Yang Daijun , Ming Pingwen , Zhang Cunman
Published: November 2021

We used the lattice Boltzmann method (LBM) to simulate the dynamic behavior of catalyst particles during the ink dispersion process in a proton exchange membrane fuel cell. In the two-dimensional shear element, the single relaxation time lattice Boltzmann model, also called the lattice Bhatnagar–Gross–Krook model in the LBM, was used to simulate fluid flow, while the Lagrange model was used to simulate the motion of nanoparticles. The governing equation of particle motion includes fluid drag force, electrostatic repulsion, van der Waals force, ionomer force, and Brownian force. This model can be used to explore the effect of different shear strengths on the formation of agglomerates in inks. Our results showed that shear strength significantly influenced the formation and structure of agglomerates during the dispersion phase. Compared with a Reynolds number (Re) of 500 and 2000, a Re of 1000 achieved optimal dispersion and stability. When Re is 0, 500, 1000, and 2000, aggregate particles tend to form chain structure, packed structure, regular aggregate structure, and a large number of free particles and stacked particles, respectively.
Nonlinear elasticity of wrinkled atomically thin membranes
Authors: Sarafraz Ali , Arjmandi-Tash Hadi , Dijkink Laura , Sajadi Banafsheh , Moeini Mohsen , Steeneken Peter G. , Alijani Farbod
Published: November 2021

Owing to their atomic thickness and low bending rigidity, suspended two-dimensional (2D) materials are prone to wrinkle formation. Here, we use molecular dynamics (MD) simulations to probe the effect of these wrinkles on the nonlinear elasticity of atomically thin graphene membranes. We observe a stress–strain response that consists of two linear regions that are separated by a transition. It is found that this transition is sharp in membranes where wrinkles are formed by uneven stresses at the boundaries. However, when wrinkles are formed by crystal defects, this nonlinear transition is seen to be more gradual. To capture these effects, we use a phenomenological model based on experimentally measurable quantities. We demonstrate the model’s fidelity by fitting it to the MD simulated nonlinear response of many graphene membranes providing evidence that the sharpness of the transition between the linear regions in the stress–strain response is a measure of the type of wrinkles and can be quantified by our model.
An approach of bubble generation and manipulation by using the photothermal effects of laser irradiation on light absorbing particles
Authors: Li Bo-Wei , He Jia-Wen , Bai Wen , Wang Hao-Dong , Ji Feng , Zhong Min-Cheng
Published: November 2021

The photothermal effects have shown the possibilities for applications in optical manipulation. In this paper, an approach is demonstrated to generate and manipulate a bubble using the photothermal effects. First, a high-power laser is used to irradiate the light absorbing particles for creating a microbubble. The bubble grows up to a diameter of a few hundred micrometers in several seconds due to the diffusion of dissolved gases. The bubble does not float up and is confined at the lower boundary of the sample cell by the thermocapillary force. The force is induced by laser heating of the particles at the bubble base. Second, the bubble can be manipulated following the laser focal spot. The bubble is dragged by the horizontal component of thermocapillary force. The bubble re-grows as it moves because it absorbs the dissolved gases in its migration path. The bubble floats up finally when it grows up to the maximum size. The perpendicular component of thermocapillary force can be estimated equal to the buoyancy of the floated bubble and is about 38 nN at the laser power of 130 mW. Furthermore, we show the generation and manipulation of the bubbles in a capillary. The reason for the decrease in movement velocity in the capillaries has been studied and discussed. The approach of bubble manipulation shows a potential application in transporting the microparticles.
Chipless wireless temperature sensor based on quasi-BIC resonance
Authors: Yusupov Ildar , Filonov Dmitry , Bogdanov Andrey , Ginzburg Pavel , Rybin Mikhail V. , Slobozhanyuk Alexey
Published: November 2021

Wireless sensors find use in many practical applications, where wired connections possess a limitation. New realms of global connectivity and data exchange among various devices suggest putting a sensor on a consumable level, where electronic circuits are not affordable from an economic standpoint. Chipless approaches, aiming to address the later issue, typically come with a penalty of performance degradation and, in many cases, is seen as a compromise solution. Here, we demonstrate a concept of the extremely sensitive temperature sensor based on the bound states in the continuum (BIC) approach. A ceramic half-cylinder above a ground plane is designed to support high quality factor supercavity modes with a strong resonant dependence on an ambient temperate. The operation of the sensor is experimentally demonstrated in a broad range of temperatures, spanning from 25 to 105 °C with an average sensitivity of 4 MHz/°C. The key element, leading to this performance, is high-quality ceramics, which allows supporting confined modes with moderately low Ohmic losses and extremely high-quality factors above 1000. High-performance chipless devices, which are capable to accommodate several functions with a single platform, open a venue to a new generation of wireless distributed sensors, where the main technological and outlay efforts are placed on an interrogation side.
Using C-DFT to develop an e-ReaxFF force field for acetophenone radical anion
Authors: Penrod Katheryn A. , Burgess Maximiliano Aldo , Akbarian Dooman , Dabo Ismaila , Woodward W. H. Hunter , van Duin Adri C. T.
Published: November 2021

Increased electricity usage over the past several decades has accelerated the need for efficient high-voltage power transmission with reliable insulating materials. Cross-linked polyethylene (XLPE) prepared via dicumyl peroxide (DCP) cross-linking has emerged as the insulator of choice for modern power cables. Although DCP cross-linking generates the desired XLPE product in high yield, other by-products are also produced. One such by-product, acetophenone, is particularly intriguing due to its aromaticity and positive electron affinity. In this work, constrained density functional theory (C-DFT) was utilized to develop an e-ReaxFF force field suitable for describing the acetophenone radical anion. Initial parameters were taken from the 2021 Akbarian e-ReaxFF force field, which was developed to describe XLPE chemistry. Then, C-DFT geometry optimizations were performed wherein an excess electron was constrained to each atom of acetophenone. The resulting C-DFT energy values for the various electronic positions were added to the e-ReaxFF training set. Next, an analogous set of structures was energy-minimized using e-ReaxFF, and equilibrium mixture compositions for the two methods were compared at multiple temperatures. Iterative fitting against C-DFT energy data was performed until satisfactory agreement was achieved. To test force field performance, molecular dynamics simulations were performed in e-ReaxFF and the resulting electronic distributions were qualitatively compared to unconstrained-DFT spin density data. By expanding our e-ReaxFF force field for XLPE, namely, adding the capability to describe acetophenone and its interactions with an excess electron, we move one step closer to a comprehensive molecular understanding of XLPE chemistry in a high-voltage power cable.
Dense gas effect on small-scale structures of compressible isotropic turbulence
Authors: Duan Lishu , Zheng Qinmin , Jiang Zhou , Wang Jianchun
Published: November 2021

The small-scale statistics and local flow topology of compressible homogeneous isotropic turbulence of dense gas are numerically investigated with the turbulent Mach number and Taylor Reynolds number, respectively, nearly equaling 1.0 and 153.0. The initial state of the flow field is in the inversion zone, where the fundamental derivative of gas dynamics is negative. After reaching the stationary state, the flow field includes three different gas regions: a Bethe–Zel'dovich–Thompson (BZT) region, a classical dense gas (CDG) region, and a usual gas region. In the present study, the effects of different gas regions on the statistical properties of the enstrophy production term are investigated. Based on Helmholtz decomposition, it is found that the enstrophy production mainly comes from its solenoidal component. The dense gas effect reduces the production of enstrophy in the compression region and weakens the loss of enstrophy in the expansion region. Furthermore, the properties of flow topology based on the three invariants of the velocity gradient tensor are studied. The expansion region is mainly occupied by the BZT and CDG regions. In the expansion region, the dense gas effect significantly reduces the expansive vortex structure and weakens the contribution of this structure to the enstrophy loss.
Vortex control strategy for unsteady aerodynamic optimization of a plunging airfoil at a low Reynolds number
Authors: Wang Lei , Feng Li-Hao , Liang Yan , Chen Yi-Long , Li Zhen-Yao
Published: November 2021

This study has explored effective flow control strategies to improve unsteady aerodynamic performance of a plunging airfoil at a low Reynolds number of Re = 59 000 through controlling the leading-edge vortex (LEV) formation and development. The leading-edge blowing control is first utilized to directly strengthen the LEV by injecting momentum into the separated leading-edge shear layer. The influence of the momentum coefficient on the vortical evolution and aerodynamic forces is more significant than that of the exit width. As the momentum coefficient increases in a certain range, the LEV can be enhanced, thereby increasing the maximum unsteady lift. However, it is found that an accelerated detachment usually occurs with enhancement of the LEV as the secondary vortex is also promoted by blowing, leading to a reduced duration of high lift compared with the baseline case. In order to solve such a control problem of the LEV, the control strategy of the combined blowing and suction is further proposed, which could increase the LEV strength and concurrently delay the LEV detachment to some extent through inhibiting the growth of the secondary vortex. As a result, the unsteady aerodynamic performance of the plunging airfoil has been further improved with a significant increase in the maximum lift coefficient and a moderately prolonged duration of high lift.
Threshold switching in solar cells and a no-scribe photovoltaic technology
Authors: Karpov Victor G. , Shvydka Diana , Bista Sandip S.
Published: November 2021

We show that thin film cadmium telluride (CdTe) solar cells exhibit the phenomenon of threshold switching similar to that in phase change and resistive memory. It creates a conductive filament (shunt) through the solar cell reaching the buried electrode such as transparent conductive oxide in CdTe based photovoltaics (PV). While in the existing PV, the buried electrode was routinely contacted via laser scribe filled metals, our work paves a way to an alternative technology of no-scribe PV.
Observation of the solid and liquid separation after the shock propagation in a two-dimensional Yukawa solid
Authors: Qiu Pengwei , Sun Tianyue , Feng Yan
Published: November 2021

After the propagation of compressional shocks in a two-dimensional (2D) Yukawa solid, the structure and dynamics of the postshock region are investigated using molecular dynamical simulations. When the compressional speed is significantly higher than 0.354a0ωpd, the postshock region melts completely; however, when this compressional speed is much lower than 0.283a0ωpd, the postshock region is still in the solid state. It is found that, when the compressional speed 0.283a0ωpd≤vleft≤0.354a0ωpd, from the calculated Voronoi diagram, the postshock region clearly exhibits the coexistence of the solid close to the compressional boundary and the liquid in the other part. The calculated averaged kinetic temperature profile in the postshock region exhibits a roughly linear increase in front of the compressional boundary, and the spatial portion whose averaged kinetic temperature is lower than the melting point agrees with the solid region determined directly from the Voronoi diagram. This spatial variation trend of the averaged kinetic temperature in the postshock region is attributed to the dynamical heterogeneity of the 2D Yukawa systems, which is more severe when the mean kinetic temperature is around the melting point. Test runs with various conditions further confirm this interpretation.
Intermixing reduction in ultra-thin titanium nitride/hafnium oxide film stacks grown on oxygen-inserted silicon and associated reduction of the interface charge dipole
Authors: Smith Jeffrey A. , Ni Kai , Takeuchi Hideki , Stephenson Robert J. , Chen Yi-Ann , Hytha Marek , Li Shuyi , Nicollian Paul E. , Mears Robert J. , Datta Suman
Published: November 2021

Oxygen-insertion (OI) layers in Si were found to reduce the intermixing of a 3.0 nm titanium nitride (TiN)/3.5 nm hafnium oxide (HfO2) film stack, as measured by secondary ion mass spectroscopy (SIMS), x-ray photoelectron spectroscopy (XPS), and high-resolution Rutherford backscattering spectroscopy (HR-RBS). In addition, a 5% reduction in HfO2 film density and modification of in-gap state densities of bulk HfO2 film were observed from HR-RBS and absorption spectra from spectroscopic ellipsometry (SE), respectively. Furthermore, the barrier height at HfO2/Si was found to increase by 250 mV from Fowler–Nordheim (F–N) tunneling characteristics, and 172 mV lower flatband voltage (VFB) was observed from capacitance–voltage (C–V) characteristics. These observations suggest that interfacial charge dipole formation of the high-k dielectric/metal gate (HKMG) stack on Si follows the O-vacancy model, in which charge dipole is explained as electrostatic energy stored at the interface from the intermixing process involving electron transition from oxygen vacancy in metal oxide to Si. OI-Si modifies the balance of the oxygen flux due to the supply of partially ionized oxygen in Si and, thus, leads to the reduction of the intermixing phenomena, modification of the resultant film properties, and reduction of the interfacial charge dipole. This discovery opens up a new technique for tuning HKMG electrical characteristics.
Trapping positions in a dual-beam optical trap
Authors: Rafferty Aidan , Preston Thomas C.
Published: November 2021

Optical trapping has become an important tool in a wide range of fields. While these traps are most commonly realized using optical tweezers, dual-beam optical traps offer specific advantages for certain experiments. It is commonly assumed that a particle will become trapped midway between the focal points of the two beams. However, this is not always the case. We perform a theoretical and experimental investigation of trapping positions of weakly absorbing, spherical particles in a dual-beam optical trap. We evaluate the effect of offsetting the beams in the direction of propagation and identify four regimes with distinct trapping behavior. The effect of an offset perpendicular to the propagation direction and an imbalance in power between the two beams is also considered. Experiments utilize an aqueous aerosol particle whose size can be readily controlled and monitored over hundreds of nanometers. As such, it serves as an excellent probe of the optical trap. We demonstrate that it is possible to fit the evolution of the particle trapping position in order to determine the position of the particle relative to the focal point of each beam. The results presented here provide key insights into the workings of dual-beam optical traps, elucidating more complex behaviors than previously known.
Numerical study on stability of diamagnetic levitation of a single-layer graphene sheet
Authors: Inui Norio
Published: November 2021

Strong diamagnetic interactions enable carbon materials such as graphite plates and organisms to levitate stably in the atmosphere without active control. Although the repulsive force caused by diamagnetism becomes weak as the size of the object decreases, the necessary force against gravity also decreases. Thus, a nanocarbon material such as a single-layer graphene sheet may be levitated by the diamagnetic force. However, the stability worsens as the dimensions of the sheet decrease. The dominant factors affecting the stability of the diamagnetic levitation of nanomaterials are the Brownian motion and attractive surface forces such as the Casimir interactions. We calculate the potential energy of a square graphene sheet in two states, vertical and horizontal to a magnet, and considered the transition rate between these states based on Kramers’ theory for the escape problem. Furthermore, the stiction of a single-layer graphene sheet onto a substrate caused by the Casimir force, which discontinues the levitation, is examined.
Investigation of endwall effect on transitional flow inside compressor cascade passage at low Reynolds number
Authors: Li Zhihui , Agarwal Ramesh K.
Published: November 2021

Laminar-to-turbulent transitional flow plays a key role in determining the overall aerodynamic performance of turbomachinery. In this paper, the physical mechanisms concerning transitional flow inside compressor cascade passages at low Reynolds number condition are investigated based on the large eddy simulations. Two categories of cascade flow simulations are conducted: one is for the quasi three-dimensional (3D) cascade flow without endwalls, i.e., the translational periodic boundary conditions are employed for hub and shroud surfaces, while the other focuses on the fully 3D cascade passage flow. Special emphasis is placed on the effect of endwalls on the laminar-to-turbulent transitional flow inside the compressor cascade passage. In addition, two levels of freestream turbulent intensity are set in these simulations. It is concluded that the endwall boundary layer flow has a non-ignorable influence on transitional flows in the lower-span region. Under the condition of low freestream turbulence intensity, the original laminar separation-induced transition pattern dominating the mid-span suction surface evolves to become natural and bypass transition flow when approaching the endwall region. With increase in the incoming turbulent intensity, the natural transitional flow disappears, and the cascade suction surface is dominated by the bypass transitional flow. Moreover, the blade loading near endwall is reduced and the aerodynamic loss on lower spanwise airfoil sections is substantially increased when compared to the cascade without endwall. The physical mechanisms concerning transitional flow described in this paper might provide some meaningful guidance toward developing advanced turbomachinery.
Elaborated thermochemical treatment of HF, CO, N2, and H2O: Insight into HEAT and its extensions
Authors: Thorpe James H. , Kilburn Josie L. , Feller David , Changala P. Bryan , Bross David H. , Ruscic Branko , Stanton John F.
Published: November 2021

Empirical, highly accurate non-relativistic electronic total atomization energies (eTAEs) are established by combining experimental or computationally converged treatments of the nuclear motion and relativistic contributions with the total atomization energies of HF, CO, N2, and H2O obtained from the Active Thermochemical Tables. These eTAEs, which have estimated (2σ) uncertainties of less than 10 cm−1 (0.12 kJ mol−1), form the basis for an analysis of high-level ab initio quantum chemical calculations that aim at reproducing these eTAEs for the title molecules. The results are then employed to analyze the performance of the high-accuracy extrapolated ab initio thermochemistry, or High-Accuracy Extrapolated Ab Initio Thermochemistry (HEAT), family of theoretical methods. The method known as HEAT-345(Q), in particular, is found to benefit from fortuitous error cancellation between its treatment of the zero-point energy, extrapolation errors in the Hartree-Fock and coupled cluster contributions, neglect of post-(T) core-correlation, and the basis-set error involved in higher-level correlation corrections. In addition to shedding light on a longstanding curiosity of the HEAT protocol—where the cheapest HEAT-345(Q) performs comparably to the theoretically more complete HEAT-456QP procedure—this study lays the foundation for extended HEAT variants that offer substantial improvements in accuracy relative to the established approaches.
Numerical study of pressure loads generated by a shock-induced bubble collapse
Authors: Goncalves da Silva Eric , Parnaudeau Philippe
Published: November 2021

This paper presents a numerical study of the strong loads caused by the collapse of an air bubble immersed in water in the vicinity of a wall and impacted by a normal shock wave. Simulations are performed using an efficient parallel fully compressible two-phase solver based on a homogeneous mixture model. Different configurations are investigated by varying the distance of the initial bubble to the wall. Comparisons are done with exiting results and with two-dimensional simulations highlighting large discrepancies on the computed pressure peaks. The computations show that the stand-off distance has significant effects on the collapse dynamics and the maximum wall pressure leading to potential wall damage. A power-law is proposed for the evolution of the maximum pressure peak as a function of the stand-off distance. Finally, a twin-bubble collapse is computed illustrating collective effects and the amplification of pressure peak at the wall.
On the wetting behavior of surfaces in boiling
Authors: Ardron K. H. , Giustini G.
Published: November 2021

Nucleate boiling heat transfer is strongly influenced by surface wettability as characterized by the Young's contact angle, θY. The contact angle is usually obtained from measurements on sessile droplets on horizontal test surfaces, but in the case of water at high temperatures and pressures, θY values from droplet experiments appear to be typically 30°–50° higher than values needed to explain bubble departure sizes for similar surfaces and temperatures. We explain the differences between θY values for droplets and vapor bubbles by using the surface adsorption theory of Adamson. This theory suggests that in the case of bubble formation in high pressure boiling, as the non-wetted surface inside the bubble is in contact with a saturated vapor, it will be covered by an adsorbed liquid layer of nanoscale thickness. Droplet experiments, on the other hand, generally use autoclaves pressurized by permanent gases in which the vapor pressure is far below saturation: in these relatively dry gases, the adsorbed liquid nanolayer is expected to be absent. We suggest that the presence of the adsorbed layer in the case of vapor bubbles will increase the work of formation of a new wetted surface by an amount comparable to the liquid surface tension, resulting in a significant reduction in θY. We show that by applying Adamson's model with plausible choices for unknown parameters, it is possible to explain the magnitude of the differences in θY in bubble and droplet experiments and to explain why θY appears much less sensitive to surface material conditions in the case of departing vapor bubbles than in the case of sessile droplets. We conclude that θY measurements for sessile droplets on heated surfaces in pressurized gas rather than saturated vapor environments may not be relevant to vapor bubbles and values should not be used directly in models of nucleate boiling.