bluuebunny/crossref_metadata_2025 huggingface dataset:
A parallel 3D image segmentation method for Coronary CT Angiography
Authors: Chen Yu
Published: May 2022

Coronary artery (CA) disease is one of the major cardiovascular diseases that has been proved to be the leading cause of human death in world. In this paper, a 3D image segmentation algorithm based on Lattice Boltzmann (LB) is proposed for 3D CA segmentation. After investigating the behavior of Boundary Treatment schemes, a non-equilibrium extrapolation scheme is applied to keep the stability of the computation, and reduce the frequency of the re-initialization. The denoising and clipping method are also proposed for the segmentation refining. The segmentation result shows our LB model for 3D CAD segmentation is effective. More importantly, the LB model has natural parallelism. Our model can run on massively parallel architectures, ranging from inexpensive embedded FPGAs and DSPs up to GPUs.
Text sentiment classification method based on DPCNN and BiLSTM
Authors: Huang Weichun , Nie Jiawei , Huang Xiaohui
Published: May 2022

In recent years, deep learning network models have been widely used in the aspect of text emotion classification and have achieved remarkable achievements. The traditional TextCNN network can only extract local spatial features of sentences, while the improved DPCNN model has the ability to capture long-distance dependence of the text by deepening the network depth. At the same time, bi-LSTM model is characterized by learning temporal information of text. Therefore, this paper combines the two models, which can not only obtain the spatial local information of the text, but also further strengthen the ability to understand and learn the semantic association information of the text. Experimental results show that the classification effect of the model used in this paper is better than the single model.
Synthesis and characterization of Co3O4@TiO2 photoelectrode materials
Authors: Wu Weihao , Wang Xiaoyu , Zhu Luping
Published: May 2022

The Co3O4@TiO2 photoelectrode was prepared in two steps on the F-doped SnO2 conductive glass (FTO). The appearance and internal structure of the samples were tested by XRD and SEM, The photoelectric properties of the electrodes were tested by an electrochemical workstation. Photoelectrochemical (PEC) test results shows that the photocurrent density of Co3O4@TiO2 photoelectric electrode is 0.8mA ▪ cm-2.
Research on preview control algorithm of PRS-XY hybrid machine tool based on kinematics calculation
Authors: Li Lina , Sun Hongchang , Niu Zhigang
Published: May 2022

This paper presents a preview control algorithm (PCA) for hybrid machine tool based on kinematics calculation. HMT (Hybrid Machine Tool) combines the flexibility of parallel structure with the extensibility of series structures. The kinematics are calculated and analyzed as well as the calculation process. Due to the complexity of its structure and kinematics algorithms, a motor PCA is proposed in the situation of calculation failure and used to reduce the corresponding motor vibration. The experimental results shows that the PCA is an effective way to detect and suppress the motor vibration and shock during the motion control of PRS-XY HMT.
Stability analysis and simulation based on an improved Aw-Rascle model
Authors: Hu Jiadi , Ai Wenhuan , Liu Dawei
Published: May 2022

In this paper, the improved Aw-Rascle model with viscosity term is developed to a new nonlinear dynamical system composed of ordinary differential equations, by using traveling wave substitution and a kind of variable substitution. The stability of the system is discussed by the method of phase plane analysis after getting the travelling-wave solutions, then the final data is simulated by Matlab to verify the analysis conclusion.
The theoretical framework of consumer service APP on mobilephone affecting urban commercial space
Authors: Wang Linshen , Zhang Pu , Gao Shaojie , Song Yuhan , Fan Yong
Published: May 2022

The purpose of this paper is to study consumer service-oriented APP and try to build a theoretical framework of its impact on urban space. The Physical space space when consumers use APP is defined as “window space”. Based on constructing the dynamic mechanism for the reorganization and diffusion of consumer service-oriented APP, this paper puts forward the hypothesis that “window space” gathers the physical space of service industry. Focusing on the spatial development in the Internet era, this paper predicts the transformation of urban space from “business center” to “crowd center”.
Research on the relationship between urbanization, industrial structure and urban-rural income gap-Taking Sichuan province as an example
Authors: Li Bing , Liu Yinfeng
Published: May 2022

This paper selects three indicators of urbanization, industrial structure and urban-rural income gap to construct a three-dimensional VAR model. Through Granger causality test, impulse response function and variance decomposition methods, a dynamic analysis of urbanization and industrial structure on urban-rural income gap in Sichuan Province has been carried out. The research shows that: urbanization and industrial structure have an important impact on the urban-rural income gap in Sichuan Province. Urbanization and the urban-rural income gap present a “U-shaped” relationship, that is, in the initial stage when the level of urbanization increases, the urban-rural income gap will be narrowed, and when urbanization develops to a certain degree, the gap will gradually be widened. The relationship between the industrial structure and the urban-rural income gap is an “inverted U-shaped” relationship, that is, the urban-rural income gap will be widened when the industrial structure is at a lower level. As the industrial structure is optimized and upgraded, the gap will gradually be narrowed.
Network attack evaluation model based on directed weighted complex network and fuzzy AHP method
Authors: Chi Luchen , Wu Bin
Published: May 2022

At present, most of the network attack effect evaluation is based on mathematical theory. The calculation process is influenced by artificial judgment, and the research on the dependence and influence between indicators is not sufficient, so the index weight setting is too subjective. This paper proposes a network attack effect evaluation model based on directed weighted complex network, and constructs an index architecture based on attribute-attack type-atomic function-evaluation index four-layers subnetwork. The index importance calculation method is given by combining the complex network theory with the traditional fuzzy analytic hierarchy process. Finally, taking the password cracking attack as an example, it is proved that this method is helpful to explore the impact mechanism of indicators on attributes, fully considers the relationship between indicators, simplifies the index system and improves the evaluation efficiency.
Preparation of High-barrier Polyethylene Terephthalate bottle by Microwave Plasma Enhanced Chemical Vapor Deposition
Authors: Yin Lianhua
Published: May 2022

In this work, we reported the investigation of diamond-like carbon (DLC) coating on the inner surface of polyethylene terephthalate (PET) bottles by Microwave Plasma Enhanced Chemical Vapor Deposition to improve their barrier properties. We used 2.45 GHz microwave to generate plasma, acetylene (C2H2) and argon (Ar) were used as monomer gas and diluted gas. The effects of plasma process parameters on deposition uniformity and barrier properties of thin films were studied in detail. In addition, we designed a new antenna shape to improve the uniformity of film deposition. We analyzed the microstructure and morphology of the DLC coating by atom force microscope (AFM). Fourier transform infrared spectroscope (FTIR) and Raman spectroscope were employed to investigate chemical composition and bonding structure. The deposition rate was obtained by Step Profiler. For the barrier properties, we measured the oxygen transmission rate (OTR) of the PET bottle coated with DLC film. It is noted that the uniformity of film deposition is affected by the process parameters and antenna shape, after optimizing the process parameters and antenna shape, the barrier property of PET bottles is improved obviously.
Cause and mechanism analysis of cracking and leakage of water wall tube
Authors: Zhao Jie , Song Fangyuan
Published: May 2022

In this paper, the cracking and leakage cause of the water wall tube was studied by means of macro morphology analysis, chemical composition analysis, microstructure detection, mechanical properties test and energy dispersive X-ray spectroscopy (EDS) analysis. The results indicated that the cracking of water wall reducer is mainly related to high temperature fatigue and sulfur corrosion. During operation, under the combined action of thermal expansion and contraction caused by frequent boiler load changes and axial alternating stress caused by pipe wall vibration, thermal fatigue cracks are gradually formed on the outer wall of the steel pipe toward the fire side. Under the combined action of the alternating stress and S corrosion, the cracks are gradually spread from outer to inner wall, and finally penetrate the tube wall, causing leakage. Finally, the corresponding preventive measures of water wall leakage are put forward to improve the safety and economy of power plant boiler.
Experimental Study on Tribological Properties of Polymer-based Composite Nano-additives Suitable for Armored Vehicle Engine Lubricating Oil
Authors: Fan Bingli , Li Zhengjie , Sun Annan , Guo Yiwei , Qi Xiaowen , Liu Changxin
Published: May 2022

Lubricating oil is known as "the blood to maintain the normal operation of machinery", and additives are an indispensable and important part of lubricating oil. In this paper, the Polymer-based Composite Nano-additive (PCNA) suitable for armored vehicle engine lubricating oil was developed, the physical and chemical properties of lubricating oil containing additives were carried out. The results showed that adding an appropriate amount (3 vol.%) of additives could improve the low-temperature fluidity of lubricating oil and improve the kinematic viscosity of lubricating oil without affecting the viscositytemperature characteristics of lubricating oil. The four-ball testing machine, high temperature end face testing machine and engine bench are used to measure the anti-friction lubrication effect and anti-wear ability improvement effect of the additive on lubricating oil. The experimental results show that the additive can effectively improve the antifriction, lubrication and anti-wear performance of lubricating oil. In addition, the addition of the additive can effectively improve the running state of the engine, and the engine noise is obviously reduced. Finally, the additives developed in this paper are compared with three common brand additives in the market by using the high temperature end face testing machine. The results show that the additive developed in this paper has certain advantages in improving the antifriction and lubrication effect of lubricating oil.
Study of quantitative structure-property relationship for density of ionic liquids based on Monte Carlo optimization
Authors: Jia Xingang , Wang Wenzhen , Yang Bo , Du Chunbao
Published: May 2022

Ionic liquids (ILs) have attracted increasing interests and applications due to its unique physiochemical properties. Density is a vital physical property of ILs. In this work, a comprehensive collection of density data is conducted on 184 variable ILs. The study of quantitative structure-property relationship (QSPR) is carried out for the selected density data of ILs using simplified molecular input line entry specification (SMILES) as the representation of the molecular structure of ILs by means of CORAL software. QSPR relationships were constructed with the balance of correlations (BC) and the classic scheme. Results from three random splits displayed desirable models for predicting the external test set with the correlation coefficient (R2) and cross validated correlation coefficient (Q2) in ranges of 0.8234–0.9770 and 0.7599–0.9745, respectively. The best predictions obtained by the balance of correlations along with the global SMILES descriptors are included in the modeling process. The average statistical characteristics of the external test set are the following: n =36, R2 =0.9770, Q2= 0.9745, standard error of estimation (s)=0.023, mean absolute error (MAE) =0.018 and Fischer F-ratio (F)=1443
Research on a mechanical model of coal and rock around well based on variable temperature
Authors: Yu Sheng , Zhang Jie , Li Xin , Li Cuinan , Li Rongxin
Published: May 2022

To analyze the mechanical properties of coal and rock under variable temperature, the mechanical model of coal and rock around the well under variable temperature is studied based on elastic-plastic mechanics and thermodynamic theory. The control equations of coal and rock deformation, seepage field, and temperature field around the well considering temperature and clay mineral content are derived. On this basis, the finite element numerical simulation is carried out by using the relevant parameters obtained from coal and rock mechanics experiments. The numerical simulation results show that the coal rock strength, peak stress, and peak strain show a decreasing trend when the temperature increases and the simulation results of the coal samples are consistent with the experimental results, which verifies the reasonableness of the mechanical model.
Infrared Spectroscopy Method for Detecting the Content of Antioxidant Irganox 1076 in Polypropylene
Authors: Zheng Qiukai , Fan Jingjing
Published: May 2022

A method for rapid determination of antioxidant Irganox 1076 in polyolefin by Fourier transform infrared spectroscopy was established. By comparing the infrared spectra of Irganox 1076 and polypropylene, the absorption peak of Irganox 1076 at 1738 cm-1 was selected as the detection peak. Within the concentration range involved, the standard curve equation of Irganox 1076 in PP is y = 0.00593 + 0.12681x, and the linear regression coefficient is 0.98742. The standard curve was used to determine the content of Irganox 1076 in the actual sample, and the maximum relative error was 6.85%. The method is accurate, rapid and sensitive, which can be used for on-line monitoring of processing and using polyolefin products.
Preparation of nano α-Fe2O3 and γ-Fe2O3 and used for elemental mercury removal
Authors: Tan Zengqiang , Kong Fanhai
Published: May 2022

The rod-shaped nano α-Fe2O3 and γ-Fe2O3 were prepared by a hydrothermal method. And the crystal phase structure, particle size, morphology and surface area of the synthesized nano α-Fe2O3 and γ-Fe2O3 were characterized by XRD and BET analysis. The removal of gaseous elemental mercury by nano α-Fe2O3 and γ-Fe2O3 was carried out on a fixed bed reactor. The effects of oxygen, bed temperature, particle size and acid flue gas components have been discussed. The results show that elemental mercury could be oxidized by nano α-Fe2O3 and γ-Fe2O3 with the presence of oxygen.
Simulation analysis of single solar floating photovoltaic panel structure based on wind direction change
Authors: Bei Yaoping , Yuan Bingqing , Feng Fei , Deng Xia
Published: May 2022

This paper adopts Sharepower solar floating photovoltaic power station unit. The structure is simulated and analysed, the strength of a single solar structure support is analysed, the photovoltaic array structure is analysed, and the rectangular and square structures with different wind directions are analysed.
Design and optimization of elevator car bottom structure
Authors: Huang Naiqiu , Song Mengmeng , Xiao Shungen , Zheng Zhipeng
Published: May 2022

Taking the elevator car bottom structure as the research object, the car bottom sheet metal process structure model was established by the three-dimensional design software SolidWorks. The part connection and support were considered in the simulation, and the mesh division finite element analysis was carried out to study static stress characteristics of the car bottom structure under load. The car bottom structure is optimized by introducing crisscross weldments according to the characteristics. The simulation results show that all the performances are improved, so as to illustrate the effectiveness of structural optimization, which provides theoretical basis for car bottom structure design.
Stress analysis of pipelines with small misalignment under internal pressure using fast modelling system ABAP
Authors: Yan Sunting , Liu Zhongqiang , Hu Jiansheng , Chen Yonggui , Shen Xiaoli , Teng Guoyang
Published: May 2022

This paper presents a numerical finite element analysis of pipelines with small misalignment under internal pressure using a developed fast pipeline modelling system ABAP using Python development environment of ABAQUS. The effect of small misalignment is shown to affect at most 10% of stress levels. Extensive parametric analyses have been conducted on the pipe length, pipe thickness. Pipe length has trival effect on non-uniform stress distribution when length/diameter ratio is greater than 1. For thinner pipe, misalignment amplifies the circumferential non-uniformity more significantly than thicker pipe. This paper serves to enhance the understanding of pipes with small installation misalignment defects under pure internal pressure.
Study on Serviceability of Transition Section Between Road and Tunnel
Authors: Zhong Chonghui , Cheng Bingwei , Wang Linhao , Yu Shijie
Published: May 2022

The determination of allowable differential settlement in bridge transition is a key problem to prevent vehicle jump at bridge head, but there are few theoretical research achievements in this aspect atroduction home and abroad. In this paper, four different structures of the road surface of The Sanyangchuan tunnel and the lead project are studied. The allowable differential settlement of asphalt pavement is calculated by asphalt pavement-layer system, and the allowable differential settlement is calculated by Ladan Lasse transform.
Analysis of Mechanical Properties of Loess with Lime Incorporation Ratio
Authors: Wu Tiehai , Jia Zhaofeng , Rong Baogui , Zhao Laishuan
Published: May 2022

Taking loess as the research object, the effect of lime content on mechanical properties of loess was studied. Firstly, the basic physical parameters of loess were obtained by laboratory physical index test and improved by lime. Secondly, the mechanical parameters of lime-modified loess were obtained by heavy compaction test and liquid-plastic limit test under different incorporation ratios (3%, 5%, 7%, 9%). Finally, the shear strength parameters and compressive strength of improved soil samples were obtained by unconsolidated and undrained triaxial shear test and unconfined compressive strength test respectively. The results showed that the liquid limit, plastic limit and plastic index of the loess improved by adding lime increased compared with the original soil sample, indicating that the binding force between soil particles was improved and the plasticity was enhanced. The variation range of dry density and water content had no obvious relationship with the dosage of lime. At the same time, the compressibility of soil is reduced and the collapsibility of soil is eliminated. With the increase of age, the strength of lime-modified soil also increases. Through unconsolidated and undrained triaxial shear tests and unconfined compressive strength tests, the strength of the loess improved by adding lime is significantly improved, and the strength of soil-cement increases with the increase of the dosage, and the water stability is obviously improved.
Study on the organization and properties of medium-Mn steel with V
Authors: Yang Hongru , Liu Xiaoyan
Published: May 2022

V is an important strengthening element in alloy steels, and its addition to the steel significantly improves the overall performance of the material. This paper describes the principle of V for optimizing the properties of medium-Mn steels. The excellent properties of V-containing Mn steels and their applications in practical industrial production are presented.
Research on the influence of the geometric characteristics of surrounding rock fractures on the macroscopic mechanical properties of rock-like materials based on PFC
Authors: Zhu Xiaoye
Published: May 2022

The surrounding rock of coal mining face often contains numerous micro-cracks, and these microcracks greatly restrict the mechanical strength of the rock. Mechanical properties of rock degraded by joints and fissures in rock,, taking the Mesozoic three-stream pluton granite in Dandong City, Liaodong uplift area as an example,, establish a particle flow model and use the "trial and error method" to repeatedly calibrate the microscopic parameters until they are consistent with the actual situation,, uniaxial compression tests were performed on rock masses with different fissures, and 16 orthogonal discrete element numerical simulation experiments with 4 factors and 4 levels were carried out. Based on multiple linear regression analysis, the influence of four factors on the mechanical properties of granite was analysed, and the influence of single factor on the macro-mechanical properties of granite was studied through numerical experiments. The results show that the effect of the crack geometry on the peak strength of granite is greater than the effect on the elastic modulus of granite; The order of the influence degree of the crack geometric characteristic parameters on the peak strength is the crack Y-axis position component > the crack X-axis position component > the crack length > the crack inclination angle; The order of the influence degree of the crack geometric characteristic parameters on the elastic modulus is the crack X-axis position component > the crack Y-axis position component > the crack length > the crack inclination angle; The crack initiation position gradually moves to both ends of the crack as the angle increases. The specimen is mainly dominated by tension cracks, and the crack tip is accompanied by local shear failure; The longer the crack length, the lower the peak strength of the granite, and the worse the stability; The positional change of primary microcracks in granite mainly changes the peak strength and post-peak stress-strain state of the rock sample, but has no significant effect on the elastic modulus. The research results have certain reference value for predicting the mechanical properties of fractured granite.
How cooperative advertising interacts with distributional contracts in a dual-channel system
Authors: Li Jingyan , Ji Xiang , Chen Zhixin , Wu Jie
Published: May 2022

With the development of E-commerce, an increasing number of online platforms are conducting advertising campaigns to expand their sales. In some situations, the manufacturer is willing to share the advertising cost, while in others it is not. Additionally, recently, many online platforms have started choosing an agency contract, instead of a wholesale contract, to obtain a predetermined proportion of revenue from the manufacturer to make profits. This paper studies a scenario of a manufacturer selling through both a direct channel and a platform channel to investigate the interaction between a manufacturer’s cooperative advertising strategy and a platform’s distribution contract choice. We develop a stylized model based on game theory to drive the optimal prices and advertising level under different contracts. By using a representative consumer function, we drive the following interesting results. Firstly, under the wholesale contract, a manufacturer prefers cooperating only when the cost-sharing rate is small, but under an agency contract, when the revenue-sharing rate is large, the manufacturer will not choose to cooperate even if the cost-sharing rate is low. Secondly, the platform’s profit does not always increase in the revenue-sharing rate. Finally, under some conditions, the platform would prefer that the manufacturer not share the cost. Specifically, when the competition intensity is small and the revenue-share rate is high, the platform would rather choose an agency contract to cover all advertising costs on its own than a wholesale contract where the manufacturer is willing to share advertising costs. We also consider direct channel advertising as well in an extension, and the qualitative results still hold.
Outcome beim prolongierten Weaning
Authors: Paul Andrea , Suchi Stefan , Schönhofer Bernd
Published: May 2022

Einleitung Die Zahl der Patienten, die sich nach längerdauernder Beatmungstherapie im prolongierten Weaning (Respiratorentwöhnung) befinden, nimmt seit Längerem zu. Weaning-Einheiten (WE) im Netzwerk der pneumologischen Beatmungszentren „WeanNet“ haben sich mit Therapieverfahren auf dieses Kollektiv spezialisiert. In dieser Studie analysieren wir das Outcome der Patienten im prolongierten Weaning, die in den Jahren 2011–2015 in unserer WE behandelt wurden.

Methoden Es wird in folgende 4 Outcome-Gruppen unterschieden: 1. Erfolgreiches Weaning ohne maschinelle Beatmung, 2. Erfolgreiches Weaning mit nicht invasiver Beatmung (NIV), 3. Weaning-Versagen mit nachfolgender invasiver Beatmung und 4. In der WE verstorben.

Ergebnisse 272 Patienten verteilten sich wie folgt auf die 4 Outcome-Gruppen: Gruppe 1: 116 Patienten (42,6 %), Gruppe 2: 52 Patienten (19,1 %), Gruppe 3: 45 Patienten (16,5 %) und Gruppe 4: 59 Patienten (21,7 %). Die Behandlungsdauer war v. a. abhängig von den Begleiterkrankungen und dem Hämoglobinwert.

Bei Entlassung war trotz erfolgreichem Weaning das Tracheostoma lediglich bei 60,3 % der Patienten mit kontinuierlicher Spontanatmung und 67,3 % der Patienten mit NIV vollständig verschlossen.

Nach Entlassung aus der WE wurden Patienten mit Weaning-Versagen nur selten in einer Rehabilitationsklinik betreut, aber deutlich häufiger (29 %) notfallmäßig in die Klinik eingewiesen.

Die 1-Jahres-Überlebensrate der Patienten in unserer Studie lag bei 59 %. Die Hälfte der Patienten starb in weniger als 2 Jahren.

Diskussion In der Mehrzahl der Patienten gelang in der WE auch nach prolongierter Beatmung die erfolgreiche Entwöhnung. Dennoch war der Anteil der Patienten mit Weaning-Versagen und anschließender invasiver außerklinischer Langzeitbeatmung sowie die Mortalitätsrate relativ hoch. Die sich hieraus ergebenden ethischen Implikationen werden diskutiert.
Exploring the electronic properties of N-doped graphene on graphitic and pyridinic models and its interaction with K
Authors: Hidayat Yuniawan , Rahmawati Fitria , Nugrahaningtyas Khoirina Dwi , Althof Abiyyi Abdurro’Uf , Erlangga Mohamad Zola , Pujiastuti Nourma
Published: May 2022

The electrical properties of graphene doped with graphite and N-pyridine and their interaction with K+ ions have been studied using the density-functional based tight-binding (DFTB) method. Pure graphene and graphene with a single vacancy are used as comparisons. A 4 × 4 × 1 unit cell was used as the base, while an enlarged supercell consisting of primitive unit cells repeated to 40 × 40 × 1 was used for sampling. The structure and the Fermi Level of the optimized graphene agreed with the experimental data. The presence of N as a dopant in a graphitic configuration shifted the Fermi level to higher levels, while N in a pyridinic configuration shifted it to lower. Both showed an increase in the intensity of electronic activity. The presence of the dopant N resulted in the widening of the bandgap in graphene. The electrical characteristics of the examined graphenes influence the strength of the interaction with K+ ions.
Conserved patterns of functional organization between cortex and thalamus in mice
Authors: Miller-Hansen Andrew J. , Sherman S. Murray
Published: May 2022

Significance

Neuroanatomical tracing provides just a partial picture of information flow in the brain, because excitatory synapses are not all equal. Some strongly drive postsynaptic targets to transfer information, whereas others weakly modulate their responsiveness. Here, we show conserved patterns of synaptic function across somatosensory and visual thalamocortical circuits in mice involving higher-order thalamic nuclei. These nuclei serve as hubs in transthalamic or cortico-thalamo-cortical pathways. We report that feedforward transthalamic circuits in the somatosensory and visual systems operate to efficiently transmit information, whereas feedback transthalamic circuits act to modulate their target areas. These patterns may generalize to other brain systems and show how methods of synapse physiology and molecular biology can inform the exploration of brain circuitry and information processing.
Surface modification by in-situ grown TiC in the bainitic matrix using TIG arcing
Authors: Paraye Nilesh Kumar , Karmakar Anish , Ghosh Prakriti Kumar , Das Sourav
Published: May 2022

In the current study, surface modification of the steel was carried out with the in-situ formation of TiC in the bainite matrix using tungsten inert gas (TIG) arcing. The actual arcing parameters were optimised after thermal simulation considering the final phase transformation. Various characterisation techniques revealed the formation of fine nano as well as micron-sized in-situ grown titanium carbide precipitate within the bainite matrix. The morphology and coherency of fine TiC were analysed by high-resolution transmission electron microscopy. Mechanical properties of the modified surface were significantly improved owing to the combined effect of bainite and TiC formation. The coherent precipitates indicate superior wear resistance with the absence of pull-out particle during sliding wear.
The strategies for widening processing windows for perovskite solar cells: a mini review on the role of solvent/antisolvent
Authors: Chen Cong , Gao Jinwei , Feng Shien-Ping
Published: May 2022

Perovskite solar cells are promising candidates for next-generation photovoltaic devices with certified power-conversion efficiency for single-junction perovskite-based devices exceeded 25%. However, it remains challenging to fabricate a large-area and dense perovskite film using solution-based deposition methods. This is due to perovskite wet films being highly sensitive and unstable, and thus having only a narrow processing window. There is therefore a demand for ways to expand the processing window in the fabrication of perovskite films. Herein, we systematically review research on the role of precursor solutions and antisolvents during the perovskite formation process, and reveal the fundamental factors governing the width of the perovskite film-processing window. Then, we give an overview of current strategies for enlarging the processing window, which includes solvent and antisolvent engineering strategies. We conclude by summarizing current challenges in the development of perovskite solar modules with a wide processing window and provide perspectives for future development.
Phonon hydrodynamics in crystalline materials
Authors: Ghosh Kanka , Kusiak Andrzej , Battaglia Jean-Luc
Published: May 2022

Phonon hydrodynamics is an exotic phonon transport phenomenon that challenges the conventional understanding of diffusive phonon scattering in crystalline solids. It features a peculiar collective motion of phonons with various unconventional properties resembling fluid hydrodynamics, facilitating non Fourier heat transport. Hence, it opens up several new avenues to enrich the knowledge and implementations on phonon physics, phonon engineering, and micro and nanoelectronic device technologies. This review aims at covering a comprehensive development as well as the recent advancements in this field via experiments, analytical methods, and state-of-the-art numerical techniques. The evolution of the topic has been realized using both phenomenological and material science perspectives. Further, the discussions related to the factors that influence such peculiar motion, illustrate the capability of phonon hydrodynamics to be implemented in various applications. A plethora of new ideas can emerge from the topic considering both the physics and the material science axes, navigating toward a promising outlook in the research areas around phonon transport in non-metallic solids.
Active sites and deactivation of room temperature CO oxidation on Co3O4 catalysts: combined experimental and computational investigations
Authors: Yigit Nevzat , Genest Alexander , Terloev Schamil , Möller Jury , Rupprechter Günther
Published: May 2022

Co3O4 is a well-known low temperature CO oxidation catalyst, but it often suffers from deactivation. We have thus examined room temperature (RT) CO oxidation on Co3O4 catalysts by operando DSC, TGA and MS measurements, as well as by pulsed chemisorption to differentiate the contributions of CO adsorption and reaction to CO2. Catalysts pretreated in oxygen at 400 °C are most active, with the initial interaction of CO and Co3O4 being strongly exothermic and with maximum amounts of CO adsorption and reaction. The initially high RT activity then levels-off, suggesting that the oxidative pretreatment creates an oxygen-rich reactive Co3O4 surface that upon reaction onset loses its most active oxygen. This specific active oxygen is not reestablished by gas phase O2 during the RT reaction. When the reaction temperature is increased to 150 °C, full conversion can be maintained for 100 h, and even after cooling back to RT. Apparently, deactivating species are avoided this way, whereas exposing the active surface even briefly to pure CO leads to immediate deactivation. Computational modeling using DFT helped to identify the CO adsorption sites, determine oxygen vacancy formation energies and the origin of deactivation. A new species of CO bonded to oxygen vacancies at RT was identified, which may block a vacancy site from further reaction unless CO is removed at higher temperature. The interaction between oxygen vacancies was found to be small, so that in the active state several lattice oxygen species are available for reaction in parallel.
Single crystal growth and physical properties of layered compound SrCdBi2
Authors: Yang Yi , Fu Yu , Zhu Wenliang , He Junbao , Liu Bo , Liu Congbin , Li Liang , Niu Chunyao , Luo Yongsong
Published: May 2022

We have grown the high quality single crystals of SrCdBi2 successfully and investigated the physical properties systematically through measurements of magnetoresistance (MR), Hall effect, magnetic susceptibility, and specific heat measurements. The compound is a nonmagnetic 112-type pnictide with a Bi square net layer, which is potential for hosting Dirac fermions. We found that it exhibited metallic behavior with an anomaly appearing at around 210 K. MR study reveal that the electronic structure of SrCdBi2 is quasi-two-dimensional. At low temperatures, we observed magnetic field induced metal-to-insulator-like transition and resistivity plateau, nonsaturating quasilinear MR, and high carrier mobility in magnetotransport measurements, which indicate the possible existence of nearly massless Dirac fermions in SrCdBi2. The anomaly at around 210 K can be observed in resistivity, Hall effect, and magnetic susceptibility, but cannot be detected in heat capacity. This implies the anomaly might be caused by domain formation or disorder. We found that the nonsaturating linear MR in SrCdBi2 is likely caused by both of the quantum linear dispersion and the classical disorder. Our findings suggest that SrCdBi2 is a natural experimental platform for realizing the topological properties of nonmagnetic 112-type pnictides.
Chemically-adhesive particles form stronger and stiffer magnetorheological fluids
Authors: Rendos Abigail , Yee Daryl W , Macfarlane Robert J , Brown Keith A
Published: May 2022

Magnetorheological fluids (MRFs) are suspensions of magnetic particles that solidify in the presence of a magnetic field due to the particles forming chains along field lines. The magnetic forces between particles dominate the solidification process and determine the yield stress of the resulting solid. Here, we investigate how reversible chemical links between particles influence MRF behavior in terms of their yield stress and stiffness through rheological testing in flow and oscillation mode. Initially, we functionalize particles with phosphonate groups that are expected to link through hydrogen bonding and find that this MRF exhibits up to 40% higher yield stress and 100% higher stiffness than an MRF composed of unfunctionalized particles. To explain this change, we model the chemical attraction as an adhesion that supplements dipole–dipole interactions between particles. Interestingly, we find that the increase in yield stress is largest for dilute suspensions that are expected to solidify into isolated chains, while the proportional increase in yield stress is less for MRF with higher concentrations. This is explained by the higher concentration MRF forming a body-centered tetragonal lattice in which interparticle adhesion forces are no longer aligned with the applied field. To explore the possibility of dynamically tuning interparticle interactions, we functionalize particles with polystyrene polymers with thymine terminal groups that will only exhibit interparticle hydrogen bonding in the presence of a small linking molecule, namely melamine. We find that MRF formed with these particles also exhibit up to a 40% increase in yield stress and ∼100% increase in stiffness for the polymer grafted particles in the presence of melamine, due to the formation of hydrogen bonding linkages between the thymine and melamine groups. In addition to confirming the role of hydrogen bonding in increasing MRF stiffness and yield stress, these results highlight the possibility of dynamically tuning MRF performance using magnetic fields and chemical modifications.
The effective hydrodynamic radius in the Stokes–Einstein relation is not a constant
Authors: Ren Gan
Published: May 2022

Variants based on the assumption of effective hydrodynamic radius being a constant are usually adopted to test the Stokes–Einstein (SE) relation. The rationality of the assumption is examined by performing molecular dynamics simulations with the truncated Lennard-Jones-like (TLJ) model, Kob–Andersen model and ortho-terphenyl (OTP) model. The results indicate the assumption is generally not established except for special case. The effective hydrodynamic radius is observed to increase with decreasing temperature for TLJ model but is decreased for Kob–Andersen and OTP model; and which is almost a constant for TLJ particle with enough rigidity. The variant of SE relation

D
∼

T
/
η

is invalid for the three models except for the TLJ particle with enough rigidity. We propose similar inconsistency may be also existed in other liquids and the assumption should be critically evaluated when adopted to test the SE relation.
Threshold voltage reliability in flexible amorphous In–Ga–ZnO TFTs under simultaneous electrical and mechanical stress
Authors: Toledo Pablo , Hernandez-Pichardo Martha Leticia , Garduño Salvador Ivan , Hernandez-Lopez Jose Luis , Hernandez-Cuevas Francisco , Hernandez-Como Norberto
Published: May 2022

Flexible amorphous In–Ga–ZnO (a-IGZO) thin film transistors (TFTs) have been successfully demonstrated on 50 µm thick freestanding polyimide (PI) with µ
sat around 10 cm2 V−1 s−1. In the literature, common characterization of flexible TFTs consist of measuring their electrical response at different bending radius or under positive and negative gate bias stress (PBS and NBS). However, there are few studies where the flexible TFTs have been measured with a simultaneous mechanical and electrical stress. In this work, simultaneous testing under electrical and mechanical stress were carried out with a gate bias stress voltage of ±6 V during 3600 s, and with a tensile bending radius of 1, 2 and 4 mm. a-IGZO TFTs bottom gate-top contacts were fabricated on commercial Kapton HN PI by a complete photolithography process. All the PBS and NBS characteristics presented an abnormal threshold voltage left shift which was mainly explained by the adsorption/desorption of water molecules at the back channel. This V
th shift was modeled with the stretched exponential equation. Analyzed TFTs were stable under simultaneous stress until a 4 mm bending radius with electrical parameters V
th, subthreshold slope, µ
sat and I
on/I
off in the order of 0.7 V, 340 mV dec−1, 6 cm2 V−1 s−1 and 5 × 108, respectively.
State equations and tensors symmetry of non-linear piezoelectric materials
Authors: Jaramillo Alvarado A F , Torres Jacome A , De la Hidalga-W F J , Rosales-Quintero P , Ponce Arturo
Published: May 2022

The linear behavior of piezoelectric materials is well known from a century ago, but also, the non-linear behavior for these material have found a novel way of applications. Currently, the new technologies as the fifth generation of telecommunications (5G) and Internet of Things (IoT) are demanding high requirements for the performance of the devices operating under these technologies e.g. high quality factor, high thermal efficiency and device fabrication compatibility with the standard fabrication processes for integrated circuits as CMOS, FD-SOI and FinFET. In this work, the non-linear state equations for piezoelectric effect in stress-charge formulation, the transformations laws and the high order tensors structures are presented, in order to allow an easy way to implement it on FEM simulation software. The non-linear behavior of piezoelectric materials is discussed, and taking into account the analysis done in this work, three ways to implement nonlinear effects to design tunable piezoelectric devices for 5G and IoT applications are presented.
Vanishing cycle control by the lowest degree stalk cohomology
Authors: Massey David
Published: May 2022

Given the germ of an analytic function on affine space with a smooth critical locus, we prove that the constancy of the reduced cohomology of the Milnor fiber in lowest possible non-trivial degree off a codimension two subset of the critical locus implies that the vanishing cycles are concentrated in lowest degree and are constant.
C8 THE CEREBRAL PERFORMANCE CATEGORY IN THE DECISION–MAKING PROCESS OF IMPLANTING AN ICD IN OUT–OF–HOSPITAL CARDIAC ARREST SURVIVORS WITH BAD NEUROLOGICAL OUTCOME
Authors: Compagnoni S , Baldi E , Primi R , Gentile F , Bendotti S , Currao A , Bertona R , Buratti S , Raimondi Cominesi I , Taravelli E , Fava C , Moschini L , Savastano S
Published: May 2022

Introduction

According to the European Society of Cardiology guidelines secondary prevention ICD implantation is a class I indication only for those patients with an estimated survival > 1 year with a good functional status. However, it is not specified how to assess the functional status and its evaluation could be quite difficult in the case of out–of–hospital cardiac arrest (OHCA) survivors with major neurological outcomes. Cerebral Performance Category (CPC) is the most widespread scale to define the neurological and functional outcome of OHCA survivors, but it is not known if it can be used to guide ICD implantation.

Objective

To evaluate whether the presence of a bad neurological outcome (CPC > 2) at discharged could be used as a prognostic index in order to evaluate the implantation of an ICD in OHCA survivors. Materials and Methods. We considered all the patients who had a cardiac arrest from 01/10/2014 to 30/09/2019 presenting a CPC> 2 at discharge. The territory included was that of the Province of Pavia (550000 inhabitants) from 2014 to 2018 and of the Provinces of Pavia, Lodi, Cremona and Mantua (1550000 inhabitants) from 2019. We assessed the survival and the neurological status variation at 1–year.

Results

In the study period, CPR was attempted in 2998 confirmed OHCAs. 227 patients (7.6%) were discharged alive and in 218 of these, CPC was available. 51 patients (23.4%) had a CPC>2 at discharge (22 CPC = 3, 24 CPC = 4 and 5 CPC = A). 1–year follow–up was available in 200 patients: among 158 alive, 12 (7.6%) had CPC>2 (7 CPC = 3 and 5 CPC = 4). 1–year survival of patients with CPC>2 at discharge was significantly lower those discharged with CPC≤2 (39.6% vs 91.6% p < 0.001). Only 19/48 patients discharged with CPC>2 survived at 1 year: a good cerebral performance was recovered in 6 patients (31.6%), while CPC>2 persisted in 11 (58%) and the CPC value was unknown in 2 of them.

Conclusions

Our results highlight that 1–year survival is quite low in patients with CPC>2 at discharge and that an improvement in cerebral performance occurs only in a minority of them. This evidence suggests the need for clinical re–evaluation after the event in order to carefully evaluate whether to implant an ICD in this kind of patients.
C9 SUBCUTANEOUS IMPLANTABLE CARDIOVERTER DEFIBRILLATOR IN PATIENTS WITH LOW BMI: REAL–WORLD DATA FROM A EUROPEAN MULTICENTER ANALYSIS
Authors: Schiavone M , Gasperetti A , Vogler J , Mitacchione G , Gulletta S , Palmisano P , Breitenstein A , Laredo M , Compagnucci P , Angeletti A , Kaiser L , Hakmi S , Russo G , Ricciardi D , De Bonis S , Arosio R , Casella M , Santini L , Pignalberi C , Piro A , Lavalle C , Pisanò E , Denora M , Viecca M , Curnis A , Badenco N , Dello Russo A , Tondo C , Kuschyk J , Della Bella P , Tilz R , Biffi M , Forleo G
Published: May 2022

Background

One of the current limitations of the S–ICD is the relatively large size of the generator compared to the TV (transvenous) ICD. There is little evidence whether the size of the current S–ICD generator is associated with an elevated risk of device–related complications in patients with a low body mass index (BMI).

Purpose

Aim of this study was to compare the device–related complications and long–term outcomes in a large real world cohort of S–ICD recipients in patients with a BMI <18 kg/m2 compared to patients with a BMI >18 kg/m2.

Methods

All consecutive patients meeting current guideline indications for ICD implantation and undergoing implantation of a S–ICD device (Boston Scientific, Marlborough, Massachusetts, USA) at 21 European institutions enrolled in the extended ELISIR registry were used for the current analysis. Patients were classified into two cohorts, depending on the BMI at the time of device implantations: BMI < 18 kg/m2 versus > 18 kg/m2.

Results

Out of a total of 1497 pts, 58 pts (3.9%) had a BMI < 18 kg/m2. Patients with BMI <18 kg/m2 were younger (44.6±2.4 vs 50.8±0.4; p = 0.004) and more frequently female (58.6% vs 22.3%, p < 0.001). No differences in any of the other baseline characteristic were observed. Implantation techniques resulted comparable between the groups (rates of 2–incision technique: 87.8% vs 91.9%; p = 0.256; inter–muscular placement: 89.7% vs 83.3%; p = 0.198). Of note, the mean PRAETORIAN score at implantation of patients with BMI <18 kg/m2 was significantly lower (33.8±9.1 vs 54.1±47.3; p = 0.035), although the vast majority of patients in both cohorts qualified as at low risk of conversion failure (100% vs 91.4%; p = 0.436). Over a median follow up time of 22.4 [11.6–36.8] months, both overall device–related complications (5.2% vs 7.4%) and rates of inappropriate shocks (12.0% vs 8.8%) resulted comparable between the two groups (p = 0.517 and p = 0.385, respectively). Figure 1 reports Kaplan–Meier curves showing the combined incidence of device–related complications and inappropriate shocks in the two groups (log–rank p = 0.576).

Conclusion

No differences in device–related complications and long–term outcomes after S–ICD implantation were observed in patients with BMI <18 kg/m2 compared to the remaining recipients in a large multicentered real–world analysis.