bluuebunny/crossref_metadata_2025_split huggingface dataset:
Pongamia pinnatashell powder filled sisal/kevlar hybrid composites:Physicomechanicaland morphological characteristics
Authors: Jagadeesh Praveenkumara , Ningappa Vidya Sagar Honnenahally , Puttegowda Madhu , Girijappa Yashas Gowda Thyavihalli , Rangappa Sanjay Mavinkere , Khan Mohammad Rizwan , Khan Imran , Siengchin Suchart 
Published: June 2021

AbstractThe composite industry was attracted by natural fiber reinforced polymer materials for various valuable engineering applications due to its ecofriendly nature, less cost, and enhanced mechanical and thermal properties. This present work aimed at incorporating sisal and kevlar woven fabrics with the epoxy matrix and studying the effect ofPongamia pinnatashell powder on the sisal/kevlar hybrid composite. Six different laminates were prepared using hand layup method with filler percentage varying 2, 4, and 6 wt%. The prepared laminates cut according to the ASTM standards for performing different mechanical tests. Results reveal that the reduction of void percentage was observed at higher filler contents, while the incorporation of kevlar fabric enhances the impact strength by 279%, tensile strength by 89.77%, and tensile modulus value by 2% in comparison with pure natural fabric laminate L‐1. The flexural strength and interlaminar shear strength were higher for 2% filler composites, while the highest flexural modulus and hardness values were observed for 6% filler‐filled composites. The water absorption percentage was maximum for sisal laminate L‐1 and minimum for kevlar laminate L‐2. The fractured tensile and flexural specimens were analyzed by scanning electron microscopy.
Experimental and analytical investigation of 3D printed specimens reinforced by different forms of recyclates from wind turbine waste
Authors: Tahir Mazin , Rahimizadeh Amirmohammad , Kalman Jordan , Fayazbakhsh Kazem , Lessard Larry 
Published: June 2021

AbstractWaste from hundreds of thousands of tons of non‐recyclable end‐of‐life wind turbine blades will be generated within the next decades. This work studies the effect of recycled fiber categories on the tensile properties of reinforced polylactic acid (PLA) specimens made by fused filament fabrication 3D printing. Three different fiber categories, that is, virgin, ground, and pyrolyzed, are examined and compared experimentally and analytically using micromechanical models. Tensile tests are performed on different PLA specimens prepared with the three fiber categories and two fiber contents of 5% and 10% per ASTM D638. Compared to virgin fibers, both recycled fibers, that is, ground and pyrolyzed fibers, exhibit higher strength and stiffness values. Ground recycled fibers showed higher ultimate tensile strength compared to the pyrolyzed ones, while higher stiffness values were obtained for pyrolyzed fibers. Single fiber tensile tests, pull‐out interfacial strength tests, thermal analysis, and microscopic imaging are performed to evaluate parameters used in the micromechanical models. The Halpin‐Tsai and Cox models showed good agreement with the experimental modulus results with errors less than 5% for pyrolyzed fibers, while the minimum prediction error was 24.1% for strength results.
Analysis of the characteristic compounds of Citri Sarcodactylis Fructus from different geographical origins
Authors: Zheng Zhenxing , Hu Hanwen , Zeng Li , Yang Huan , Yang Tianlong , Wang Di , Zhang Chuanyang , Deng Yun , Zhang Mingzhi , Guo Dale , Deng Fang 
Published: June 2021

AbstractIntroductionCitri Sarcodactylis Fructus (CSF) is widely used as a food ingredient and a traditional Chinese medicine. In China, CSF is cultivated in many places, including Sichuan, Guangdong, Zhejiang, and Fujian provinces. The types and chemical contents of CSF from different origins may vary greatly due to the difference in climate and environmental conditions. Therefore, comparing the chemical composition of CSF from various places is vital.ObjectiveTo rapidly select potential characteristic compounds for differentiating CSF from different origins.Material and methodsThirty‐one batches of CSF samples from different regions were analysed using ultra‐performance liquid chromatography with hybrid quadrupole‐orbitrap high‐resolution mass spectrometry. Thereafter, chemometric methods, including principal component analysis (PCA) and orthogonal partial least squares discrimination analysis (OPLS‐DA), were employed to find differential metabolites among the CSF samples from various origins.ResultsPCA revealed 77.9% of the total variance and divided all CSF samples into three categories corresponding to their origins. OPLS‐DA displayed better discrimination of CSF from different sources, with R2X, R2Y, and Q2 of 0.801, 0.985, and 0.849, respectively. Finally, 203 differential metabolites were obtained from CSF from different origins using the variable importance in projection of the OPLS‐DA model, 30 of which were identified, and five coumarin compounds were selected as marker compounds discriminating CSF from different origins.ConclusionThis work provides a practical strategy for classifying CSF from different origins and offers a research foundation for the quality control of CSF.
A post curing strategy toward the feasible covalent adaptable networks in polyacrylate latex films
Authors: Gong Tianyu , Guo Longhai , Ye Jun , He Lifan , Qiu Teng , Li Xiaoyu 
Published: June 2021

AbstractThe implementation of covalent adaptable networks (CANs) in general resin system is becoming attractive. In this work, we propose a simple post‐curing strategy based on the core‐shell structured acrylate latex for the achievement on both the improved general performance and the CANs characteristics in latex films. The building to the CANs was relied on the introduction of 4,4′‐diaminophenyl disulfide as the curing agent, which cured the acetoacetoxy decorated shell polymer through the ketoamine reaction. The metathesis reaction of aromatic disulfides in the crosslinking segments enabled the thermally induced dynamic behavior of the network as revealed in the stress relaxation tests by comparison with other diamine crosslinking agents without the incorporation of disulfide. The synergism of the dynamic crosslinking of the shell polymer and static crosslinking in the core polymer contributed to the improved mechanical strength (15 MPa, strain% = 250%) and the suppressed water adsorption (~1% in 24 h of soaking) of the latex film, which exhibited above 90% of recovery in both strength and strain from a cut‐off film damage within 1 h at 80°C. Moreover, the cured latex film could be recycled, and 75% of the mechanical performance was regained after three fragmentation‐hot‐pressing cycles. These, in addition with the feasible and environmental friendly characteristics, suggest a sustainable paradigm toward the smart thermosetting latex polymers.
Robust process capability indices for multiple linear profiles
Authors: Mehri Saeed , Ahmadi Mohammad Mahdi , Shahriari Hamid , Aghaie Abdollah 
Published: June 2021

AbstractIn some statistical process control applications, the quality of a process is described by a linear relationship between the response variable(s) and the independent variable(s), which is called a linear profile. Process capability is a significant issue in statistical process control. The ability of a process to meet customer specifications or standards is measured by the process capability indices (PCIs). There are several attempts for studying the process capability in linear profiles. In this research, two robust PCIs for multiple linear profiles are proposed. In the suggested robust PCIs, the process capability is estimated using the M‐estimator and the Fast‐τ‐estimator. Performances of the proposed robust PCIs in comparison with the classical PCIs in the absence and presence of contamination are evaluated. The results show that the robust PCIs proposed in this research perform as well as the classical PCIs in the absence of contamination and much better in the presence of contamination. The proposed PCIs, using Fast‐τ‐estimator, perform better in small shifts, and the proposed PCIs, using M‐estimator, perform better in large shifts. Introduction of robust indices for multivariate multiple linear profiles is an area for further research.
Homogeneously weighted moving average control chart based on Bayesian theory
Authors: Noor‐ul‐Amin Muhammad , Noor Surria 
Published: June 2021

AbstractThe frequentist approach‐based control charts (CCs) have been widely used to monitor the performance of the process. As compare to frequentist approach, the CCs based on the Bayesian approach can be used with a small phase‐I dataset. This paper aims to propose a new homogenously weighted moving average CC based on the Bayesian theory. We have used two different loss functions, symmetric loss function as squared error loss function and asymmetric loss function as linex loss function under the informative prior as conjugate prior and noninformative prior by using posterior distribution (P dist) and posterior predictive distribution (PP dist). We calculated the values of average run length and standard deviation of run length to check the performance of the proposed homogenously weighted moving average CC based on the Bayesian theory. We also compared the proposed CC with the exponentially weighted moving average CC under the Bayesian theory. The results revealed that the proposed CC is more sensitive in the detection of small/moderate shifts than the considered CC. Finally, we presented an example based on a real‐life data for implementation purposes.
Ultrafast Pump‐Probe Spectroscopy—A Powerful Tool for Tracking Spin‐Quantum Dynamics in Metal Halide Perovskites
Authors: Chen Zhi , Dong Guoping , Qiu Jianrong 
Published: June 2021

AbstractUltrafast pump‐probe spectroscopy provides a powerful tool for deep insight into sophisticated electron–hole dynamics for materials development and devices optimization, particularly for emerging metal halide perovskites (hereafter, termed perovskites), due to their great potentials for optoelectronic and photonic applications in solar cells, light‐emitting diodes, photodetectors, and lasers. Recently, flourishing spin‐related photophysical phenomena (such as, Rashba effect, optical Stark effect, and magneto­optical effect) in perovskites and their relevant devices have experimentally been observed, attributed to huge spin‐orbital coupling effect and strong interaction of electron–photon in perovskites. However, fundamental understanding of spin‐dependent photophysics in perovskites is still at its nascent stage. In recent few years, circularly‐polarized ultrafast pump‐probe technique has pushed burgeoning development of spin‐selective photophysics in perovskites for spintronic device applications. Nevertheless, few review papers summarize this emerging field systematically, completely, and insightfully. Herein, to evoke broader attraction and research interest, recent advances in spin‐quantum dynamics in perovskites revealed by circularly‐polarized pump‐probe technique are reviewed: from the fundamentals and theories of circularly‐polarized ultrafast pump‐probe transient absorption and time‐resolved Faraday rotation spectroscopy; to the recent enlightening works on spin relaxation dynamics, spin‐selective exciton optical Stark effect, magnetic spin effect, and spin polarization dynamics. Finally, current challenges and perspectives are given.
Stability criteria of random delay differential systems subject to random impulses
Authors: Zhang Weihai , Feng Likang , Wu Zhaojing , Park Ju H. 
Published: June 2021

AbstractThis article investigates the stability of random impulsive delay differential systems with the kind of random impulsive intensity determined by an arbitrary random sequence or an irreducible aperiodic Markov chain. Moreover, the continuous dynamics are described by random delay differential equations whose random disturbances are driven by second‐order moment processes. Based on the approaches of average impulsive interval and mode‐dependent average impulsive interval, the criteria of global asymptotic stability in probability and exponential stability in th moment are constructed, respectively. In the end, the feasibility of the proposed theoretical results is verified by an example.
A tractable Bayesian joint model for longitudinal and survival data
Authors: Alvares Danilo , Rubio Francisco J. 
Published: June 2021

AbstractWe introduce a numerically tractable formulation of Bayesian joint models for longitudinal and survival data. The longitudinal process is modeled using generalized linear mixed models, while the survival process is modeled using a parametric general hazard structure. The two processes are linked by sharing fixed and random effects, separating the effects that play a role at the time scale from those that affect the hazard scale. This strategy allows for the inclusion of nonlinear and time‐dependent effects while avoiding the need for numerical integration, which facilitates the implementation of the proposed joint model. We explore the use of flexible parametric distributions for modeling the baseline hazard function which can capture the basic shapes of interest in practice. We discuss prior elicitation based on the interpretation of the parameters. We present an extensive simulation study, where we analyze the inferential properties of the proposed models, and illustrate the trade‐off between flexibility, sample size, and censoring. We also apply our proposal to two real data applications in order to demonstrate the adaptability of our formulation both in univariate time‐to‐event data and in a competing risks framework. The methodology is implemented inrstan.
Control of Texture and Morphology of Zinc Films through Pulsed Methods from Additive‐Free Electrolytes
Authors: Fuller Lee , Martin Jason , Ma Yuanman , King Seth , Sen Sujat 
Published: June 2021

AbstractWe investigate the electrodeposition of zinc on steel substrates using pulsed methods from additive‐free electrolytes in an industrially scalable parallel plate flow cell. We demonstrate that variables such as peak current and duty cycle can be used to independently control the morphology and preferential texture of the crystalline structure, which is, in turn, desirable for a variety of applications. Specifically, we have observed a transition of the preferential (002) facets at low peak current density (or low duty cycle) to (101) preferring facets at higher peak current density (or high duty cycle) as determined by the analysis of texture coefficients. Further analysis using scanning electron microscopy reveals a transition from the conventional hexagonal‐shaped particles of zinc to needle‐shaped structures, accompanied by a change in average crystallite size from 33 to 19 nanometers, determined from X‐ray diffraction studies. The variation in morphology is also correlated to crystallographic textures through the analysis of texture coefficients and an understanding of crystallization mechanisms occurring during deposition. Collectively, these results demonstrate that the morphology and crystalline orientation of zinc can be easily manipulated through tuning of the pulse parameters without the use of complex and expensive additives that have been traditionally used to achieve similar effects.
Tumor‐Specific Multipath Nucleic Acid Damages Strategy by Symbiosed Nanozyme@Enzyme with Synergistic Self‐Cyclic Catalysis
Authors: Zhao Yan , Kong Weiheng , Wang Peng , Song Guosheng , Song Zhi‐Ling , Yang Yue , Wang Youjuan , Yin Baoli , Rong Pengfei , Huan Shuangyan , Zhang Xiao‐Bing 
Published: June 2021

AbstractThe high proliferation efficiency, redox imbalance, and elevated nucleic acid repair capabilities of tumor cells severely restrict the theranostic efficacy. Selectively interference chaotic tumors with devastating nucleic acid damages (NUDs) properties are expected to overcome theranostic barriers. Here, an exquisite catalytic‐based strategy with comprehensive NUDs mechanisms is demonstrated. In this regard, enzyme (glucose oxidase, GOD) symbioses nanozyme Cu3+x(PO4)2 through biomineralization (abbreviated as Cu@GOD), GOD can disorder the metabolism by consuming glucose, thereby inhibiting the nutrition supply for nucleic acid repair. GOD‐catalyzed H2O2 guarantees the self‐cyclic glutathione depletion and reactive oxygen species generation caused by Cu3+x(PO4)2, resulted the reduced antioxidation defense and enhanced oxidation assault, ensures an indiscriminate NUDs ability. Moreover, the high photothermal effect of Cu3+x(PO4)2 induces effective tumor inhibition. Consequently, this substantial multipath NUDs strategy, with potentials of suppressing the cytoprotective mechanisms, amplifying the cellular oxidative stress, and disrupting the redox balance to ensure substantial irreversible NUDs, completely breaks the obstacle of chaotic tumors, providing new conceptual thinking for tumor proliferation inhibition.
Polyamine‐Responsive Morphological Transformation of a Supramolecular Peptide for Specific Drug Accumulation and Retention in Cancer Cells
Authors: Sun Chen , Wang Ziyi , Yang Kuikun , Yue Ludan , Cheng Qian , Ma Yan‐long , Lu Siyu , Chen Guosong , Wang Ruibing 
Published: June 2021

AbstractThe precise accumulation and extended retention of nanomedicines in the tumor tissue has been highly desired for cancer therapy. Here a novel supramolecular‐peptide derived nanodrug (SPN) that can be transformed to microfibers in response to intracellular polyamine in cancer cells for significantly enhanced tumor specific accumulation and retention is developed. The supramolecular‐peptide is constructed via the non‐covalent interactions between cucurbit[7]uril (CB[7]) and Phe on Phe‐Phe‐Val‐Leu‐Lys‐camptothecin conjugates (FFVLK‐CPT, PC). The resultant amphiphilic supramolecular complex subsequently self‐assembles into nanoparticles with a hydrodynamic diameter of 164.2 ± 3.7 nm. Upon internalization into spermine‐overexpressed cancer cells, the CB[7]‐Phe host–guest pairs can be competitively dissociated by spermine and can release free PC, which immediately form β‐sheet structures and subsequently reorganize into microfibers, leading to dramatically improved accumulation, retention, and sustained release of CPT in tumor cells for highly effective cancer therapy. Accordingly, this SPN exhibit rather low toxicity against non‐cancerous cells due to the morphological stability and fast exocytosis of the nanodrugs in those cells without abundant spermine. This study reports the first supramolecular peptide capable of polyamine‐responsive “nanoparticle‐to‐microfiber” transformation for specific tumor therapy with minimal side effects. This work also offers novel insights to the design and development of stimuli‐responsive nanomaterials as precision medicine.
Koaxiale Stahlenergiepfähle
Authors: Blanke Tobias , Reger Vitali , Döring Bernd , Göttsche Joachim , Kuhnhenne Markus 
Published: June 2021

AbstractEin entscheidender Teil der Energiewende ist die Wärmewende im Gebäudesektor. Ein Schlüsselelement sind hier Wärmepumpen. Diese benötigen eine Wärmequelle, der sie Energie entziehen können, um sie auf ein höheres Temperaturniveau zu transformieren. Diese Wärmequelle kann bspw. das Erdreich sein, dessen Wärme durch Erdsonden erschlossen werden kann. In diesem Beitrag werden in Stahlpfähle integrierte Koaxialsonden mit dem Stand der Technik von Erdsonden gleichen Durchmessers bezüglich ihrer thermischen Leistungsmerkmale verglichen. Die Stahlenergiepfähle bieten neben der Wärmegewinnung weitere Vorteile, da sie auch eine statische Funktion übernehmen und rückstandsfrei zurückgebaut werden können. Es werden analytische und numerische Berechnungen vorgestellt, um die thermischen Potenziale beider Systeme zu vergleichen. Außerdem wird ein Testaufbau gezeigt, bei dem Stahlenergiepfähle in zwei verschiedenen Längen mit vorhandenen gängigen Erdsonden verglichen werden können. Die Berechnungen zeigen einen deutlichen thermischen Mehrertrag zwischen 26 % und 148 % der Stahlenergiepfähle gegenüber dem Stand der Technik abhängig vom Erdreich. Die Messergebnisse zeigen einen thermischen Mehrertrag von über 100 %. Es lässt sich also signifikante Erdsondenlänge einsparen. Dabei ist zu beachten, dass sich damit der thermisch genutzte Bereich des Erdreichs reduziert, wodurch die thermische Regeneration und/oder das Langzeitverhalten des Erdreichs an Bedeutung gewinnt.
Comfort assessment of high‐rise timber buildings exposed to wind‐induced vibrations
Authors: Lazzarini Enrico , Frison Giovanni , Trutalli Davide , Marchi Luca , Scotta Roberto 
Published: June 2021

SummaryThe current trend of increasing the height limits of timber buildings makes wind‐induced vibrations a non‐negligible issue. The dynamics of high‐rise timber structures are discussed, focusing on accelerations and comfort assessment of the currently tallest timber building in the world, namely, the 18‐storey timber building in Norway. Verifications according to available standards were firstly carried out. Then, computational fluid dynamic analyses with Kratos Multiphysics were performed to simulate the wind flow around a rigid body. Afterward, the wind loads were applied to a single‐degree of freedom model and to a reduced finite element model, performing a one‐way coupling between the wind flow and the structure. Wind‐induced vibrations resulted particularly strong in the across‐wind direction, which is the most sensitive to the wind flow and the shape of the building. Provisions in international standards resulted to be not always enough to avoid discomfort in the occupants. Therefore, fluid dynamic analyses are suggested to simulate the actual response and verify the comfort criteria of tall timber buildings susceptible to wind‐induced vibrations.
Building Heat Load Estimation Method Including Parameter Estimation from Actual Data
Authors: Nakamura Ryosuke , Kawamura Tsutomu 
Published: June 2021

In recent years, various method of air conditioning control and making operation plans have been developed. They require a building thermal model, but for making the model detailed design data is needed. Several model construction methods have been proposed up to now, but they are for buildings surrounded by walls made with one material. In this situation for deriving the room temperature and air conditioner power consumption, a parameter estimation method for estimating heat capacities and resistances of walls with different physical properties was developed. This method consists of two steps. At the first step, in steady temperature state, the least‐squares method is used to derive thermal resistances. In the second step, in non‐steady temperature state, an Unscented Kalman Filter (UKF) is used to derive heat capacities and solar‐radiation shading coefficients. UKF is adopted for numerical stability and short operation time. With this method, it is possible to obtain the independent parameters of each wall by repeating the evaluation using a simple model. These steps were applied to data obtained by simulation. As a result, the physical parameter error of the inner and outer walls was sometimes 10–60%. On the other hand, regarding to the estimation target, the error of the indoor temperature estimation was 0.3 °C, and the error of power consumption estimation was less than 4%, so high estimation accuracy was obtained. This confirmed the effectiveness of the proposed method. © 2021 Institute of Electrical Engineers of Japan. Published by Wiley Periodicals LLC.