bluuebunny/crossref_metadata_2025 huggingface dataset:
Stable high-oxidation-state complex in situ Mn(v)–Mn(iii) transition to achieve highly efficient cervical cancer therapy
Authors: Zhang Hanjie , Zhang Yuequn , Cao Jianrong , Ma Li , Chen Tianfeng
Published: February 2022

Stable high-oxidation-state Mn complexes were employed for efficient cancer therapy through an in situ Mn(v)–Mn(iii) transition to disrupt the redox balance.
Effect of charge inversion on nanoconfined flow of multivalent ionic solutions
Authors: Rojano Andrés , Córdoba Andrés , Walther Jens H. , Zambrano Harvey A.
Published: February 2022

In a nanoconfined electrolyte, lower flow rates are computed for higher concentrations of multivalent counterions due to augmented local viscosity at the solid–liquid interface which is correlated to an increase in the magnitude of charge inversion.
Highly stable actinide(iii) complexes supported by doubly aromatic ligands
Authors: Zhang Naixin , Wang Congzhi , Wu Qunyan , Lan Jianhui , Chai Zhifang , Shi Weiqun
Published: February 2022

First-principles theory calculations proved that the doubly aromatic ligand B73− is a potential candidate for stabilizing low-valent actinide complexes.
Dehydrogenation of ammonia–borane to functionalize neutral and Li+-encapsulated C60, C70and C36fullerene cages: a DFT approach
Authors: Ghosh Avik , Banerjee Soumadip , Debnath Tanay , Das Abhijit K.
Published: February 2022

Computational investigation on the effectiveness of ammonia–borane dehydrogenation to functionalize neutral and Li+-encapsulated C60, C70and C36fullerene cages.
C–H⋯S hydrogen bonding interactions
Authors: Fargher Hazel A. , Sherbow Tobias J. , Haley Michael M. , Johnson Darren W. , Pluth Michael D.
Published: February 2022

The short C–H⋯S contacts found in available structural data for both small molecules and larger biomolecular systems suggest that such contacts are an often overlooked yet important stabilizing interaction.
Selective perrhenate/pertechnetate removal by a MOF-based molecular trap
Authors: Ming Mei , Zhou Hang , Mao Yi-Ning , Li Hai-Ruo , Chen Jing
Published: February 2022

A MOF-based molecular trap showed superior selective removal of perrhenate/pertechnetate via a nanosieve and coordination-bonding effect.
Ultra-processed food consumption and the risk of subclinical thyroid dysfunction: a prospective cohort study
Authors: Zhang Juanjuan , Zhu Fan , Cao Zhixia , Rayamajhi Sabina , Zhang Qing , Liu Li , Meng Ge , Wu Hongmei , Gu Yeqing , Zhang Shunming , Zhang Tingjing , Wang Xuena , Thapa Amrish , Dong Jun , Zheng Xiaoxi , Zhang Xu , Dong Xinrong , Wang Xing , Sun Shaomei , Zhou Ming , Jia Qiyu , Song Kun , Niu Kaijun
Published: February 2022

Prospective cohort studies linking ultra-processed foods (UPF) and subclinical thyroid dysfunction (SCTD) are limited, especially in Chinese adults.
Generative machine learning algorithm for lattice structures with superior mechanical properties
Authors: Lee Sangryun , Zhang Zhizhou , Gu Grace X.
Published: February 2022

We present a hybrid neural network and genetic optimization adaptive method incorporating Bézier curves to consider the large design space of lattice structures with superior mechanical properties.
Vertically aligned ZnCo2O4 nanoplates on Ti3C2 for high-efficiency hybrid supercapacitors
Authors: Wang Hao , Zhang Yu , Guo Enyan , Hu Chengge , Lu Qifang , Wei Mingzhi , Ma Jingyun , Si Conghui
Published: February 2022

Vertically aligned ZnCo2O4 porous nanoplates anchored on ultrathin delaminated-Ti3C2 nanosheets exhibit outstanding electrochemical performance.
The rationalized pathway from field-induced slow magnetic relaxation in CoII–WIV chains to single-chain magnetism in isotopological CoII–WV analogues
Authors: Charytanowicz Tomasz , Jankowski Robert , Zychowicz Mikolaj , Chorazy Szymon , Sieklucka Barbara
Published: February 2022

The change of the oxidation state from WIV to WV in isotopological CoII–[W(CN)8]n− chains leads to the appearence of pronounced single-chain magnet behaviour.
The precise modification of a nanoscaled Keplerate-type polyoxometalate with NH2-groups: reactive sites, mechanisms and dye conjugation
Authors: Grzhegorzhevskii Kirill V. , Denikaev Andrey D. , Morozova Maria V. , Pryakhina Victoria , Khairullina Evgeniia , Tumkin Ilya , Taniya Olga , Ostroushko Alexander A.
Published: February 2022

The interaction of alkoxysilanes with nanoscaled giant polyoxoclusters is a challenging route for efficiently building blocks for supramolecular smart design.
Modulating catalytic activity of a modified flavin analogue via judicially positioned metal ion toward aerobic sulphoxidation
Authors: Mouli M. S. S. Vinod , Mishra Ashutosh Kumar
Published: February 2022

Design and synthesis of a catalytically efficient metal-flavin complex toward aerobic sulphoxidation was achieved via judicially positioning the metal ion near the catalytic site thereby assisting the intermediate formation.
Nano-molecularly imprinted polymers (nanoMIPs) as a novel approach to targeted drug delivery in nanomedicine
Authors: Shevchenko Konstantin G. , Garkushina Irina S. , Canfarotta Francesco , Piletsky Sergey A. , Barlev Nickolai A.
Published: February 2022

The review highlights the recent advances in fabrication of molecularly imprinted polymers and their applicability for drug delivery.
Stepwise assembly and reversible structural transformation of ligated titanium coated bismuth-oxo cores: shell morphology engineering for enhanced chemical fixation of CO2
Authors: Ding Qing-Rong , Yu Yinghua , Cao Changsheng , Zhang Jian , Zhang Lei
Published: February 2022

Core–shell Bi38O44/45@TixL-oxo clusters were prepared by the stepwise assembly from soluble Bi38O45@Ti6 precursors to show modifiable shell and reversible structure transformation, which further changed their chemical fixation activities of CO2.
Role of ACSL4 in the chemical-induced cell death in human proximal tubule epithelial HK-2 cells
Authors: Kuwata Hiroshi , Tomitsuka Yuki , Yoda Emiko , Hara Shuntaro
Published: February 2022

Acyl-CoA synthetase long-chain family member 4 (ACSL4) activates polyunsaturated fatty acids (PUFAs) to produce PUFA-derived acyl-CoAs, which are utilised for the synthesis of various biological components, including phospholipids (PLs). Although the roles of ACSL4 in non-apoptotic programmed cell death ferroptosis are well-characterised, its role in the other types of cell death is not fully understood. In the present study, we investigated the effects of ACSL4 knockdown on the levels of acyl-CoA, PL, and ferroptosis in the human normal kidney proximal tubule epithelial (HK-2) cells. Liquid chromatography–tandem mass spectrometry (LC-MS/MS) analyses revealed that the knockdown of ACSL4 markedly reduced the levels of PUFA-derived acyl-CoA, but not those of other acyl-CoAs. In contrast with acyl-CoA levels, the docosahexaenoic acid (DHA)-containing PL levels were preferentially decreased in the ACSL4-knockdown cells compared with the control cells. Cell death induced by the ferroptosis inducers RSL3 and FIN56 was significantly suppressed by treatment with ferrostatin-1 or ACSL4 knockdown, and, unexpectedly, upon treating with a necroptosis inhibitor. In contrast, ACSL4 knockdown failed to suppress the other oxidative stress-induced cell deaths initiated by cadmium chloride and sodium arsenite. In conclusion, ACSL4 is involved in the biosynthesis of DHA-containing PLs in HK-2 cells and is specifically involved in the cell death induced by ferroptosis inducers.
The Adaptation of Developmental Sentence Scoring and Index of Productive Syntax to Turkish
Authors: Saban-Dülger Nur Seda , Turan Figen , Özcebe Esra
Published: February 2022

Purpose:

Language sampling analysis (LSA) plays an important role in evaluating language skills; hence, the study aimed to develop new assessment measures for the LSA in Turkish as alternatives to mean length of utterance (MLU) and the Language Assessment, Remediation and Screening Procedure. With this aim, Developmental Sentence Scoring (DSS) and the Index of Productive Syntax (IPSyn) were adapted to Turkish.

Method:

Eighty monolingual Turkish children were included in the study, and the age range was from 2;0 to 5;11 (years;months). The children were grouped with 6-month intervals, and each group had an equal number of participants in terms of gender. Their general and language development were tested with standardized tests, and language sampling was recorded during play with farm toys for 15–20 min. Reviewing literature and observing participants' production schemas were created for DSS for Turkish (DSS-TR) and the IPSyn for Turkish (IPSyn-TR) separately, and final versions were determined in consultation with experts.

Results:

DSS-TR and IPSyn-TR were significantly correlated with standardized tests, and MLU values were statistically significant (
p
< .05). Total scores increased with age; however, grammatical categories did not go up. No difference was observed between genders (
p
> .05). In DSS-TR, the “sentence point” did not affect the participants' total scores because of language characteristics (
p
> .05). Finally, DSS-TR and IPSyn-TR were seen to be correlated with each other (
p
< .05).

Conclusions:

DSS-TR and IPSyn-TR are valid, being correlated with other assessment tools, and reliable, showing a high correlation with other raters, to reflect morphosyntactic skills. Therefore, they both are alternative assessment measures that will be used in LSA and give an opportunity to clinicians to plan their intervention goals. Also, they enable clinicians to observe progress not only specific to grammatical category but also in the total scores of the children either during or at the end of the therapy.
Translating Enhanced Conversational Recast to a Telepractice Setting
Authors: Arnold Haley L. , Plante Elena , Vance Rebecca
Published: February 2022

Purpose:

This investigation adapted a well-studied language treatment method, Enhanced Conversational Recast, paired with auditory bombardment to a teletherapy format.

Method:

The study used a single case series approach (
n
= 7) to determine the feasibility of teletherapy with children ages 5 and 6 years of age. Treatment targeted grammatical errors in the context of dialogic reading and craft activities. Clinicians administered 24 doses in the form of focused conversational recasting, followed by 12 doses consisting of simple sentences containing the grammatical forms targeted for remediation. Children were treated for up to 26 sessions, with four children treated on consecutive weekdays and three treated twice a week. Treatment progress was operationalized as generalization of target grammatical forms to untreated linguistic contexts, as well as spontaneous use of the treated form. To control for nontreatment effects, generalization of an untreated form was also tracked throughout the treatment period.

Results:

Six of the seven children showed clinically meaningful gains in the use of the grammatical forms targeted for treatment within the treatment period. This was true for children enrolled in both treatment schedules. Learning for treated forms was retained after treatment was discontinued. In comparison, no change was seen for untreated forms for six of the seven children.

Conclusions:

The results suggest that this treatment method is feasible in a telepractice format, even with young children. The range of individual results is generally comparable to previous face-to-face versions of this treatment.
Treatment of Pediatric Patients With High-Flow Nasal Cannula and Considerations for Oral Feeding: A Review of the Literature
Authors: Rice Jessica L. , Lefton-Greif Maureen A.
Published: February 2022

Purpose:

High-Flow Nasal Cannula (HFNC) has become an increasingly common means of noninvasive respiratory support in pediatrics and is being used in infants and children with respiratory distress both inside and outside of the intensive care units. Despite the widespread use of HFNC, there remains a paucity of data on optimal flow rates and its impact on morbidity, mortality, and desired outcomes. Given the scarcity of information in these critical areas, it is not surprising that guidelines for initiation of oral feeding do not exist. This review article will review HFNC mechanisms of action, its use in specific populations and settings, and finally what is known about initiation of feeding during this therapy.

Conclusions:

The practice of withholding oral feeding solely, because of HFNC, is not supported in the literature at the time of this writing, but in the absence of safety data from clinical trials, clinicians should proceed with caution and consider patient-specific factors while making decisions about oral feeding. Well-controlled prospective clinical trials are needed for development of best practice clinical guidelines and attainment of optimal outcomes.
Adiabatic–radiative shock systems in YSO jets and novae outflows
Authors: del Valle M. V. , Araudo A. , Suzuki-Vidal F.
Published: February 2022

Context. The termination regions of non-relativistic jets in protostars and supersonic outflows in classical novae are non-thermal emitters. This has been confirmed by radio and gamma-ray detection, respectively. A two-shock system is expected to be formed in the termination region where the jet, or the outflow material, and the ambient medium impact. Radiative shocks are expected to form in these systems given their high densities. However, in the presence of high velocities, the formation of adiabatic shocks is also possible. A case of interest is when the two types of shocks occur simultaneously. Adiabatic shocks are more efficient at particle acceleration while radiative shocks strongly compress the gas. Furthermore, a combined adiabatic–radiative shock system is very prone to developing instabilities in the contact discontinuity, leading to mixing, turbulence, and density enhancement. Additionally, these dense non-relativistic jets and outflows are excellent candidates for laboratory experiments as demonstrated by magnetohydrodynamics scaling.

Aims. We aim to study the combination of adiabatic and radiative shocks in protostellar jets and novae outflows. We focus on determining the conditions under which this combination is feasible together with its physical implications.

Methods. We performed an analytical study of the shocks in both types of sources for a set of parameters by comparing cooling times and propagation velocities. We also estimated the timescales for the growth of instabilities in the contact discontinuity separating both shocks. We studied the hydrodynamical evolution of a jet colliding with an ambient medium with 2D numerical simulations, confirming our initial theoretical estimates.

Results. We show that for a wide set of observationally constrained parameters, the combination of an adiabatic and a radiative shock is possible at the working surface of the termination region in jets from young stars and novae outflows. We find that instabilities are developed at the contact discontinuity, mixing the shocked materials. Additionally, we explore the magnetohydrodynamic parameter scaling required for studying protostellar jets and novae outflows using laboratory experiments on laser facilities.

Conclusions. The coexistence of an adiabatic and a radiative shock is expected at the termination region of protostellar jets and novae outflows. This scenario is very promising for particle acceleration and gamma-ray emission. The parameters for scaled laboratory experiments are very much in line with plasma conditions achievable in currently operating high-power laser facilities. This provides a new means for studying novae outflows that has never been considered before.
Central vacancy creation in icosahedral nanoparticles induced by the displacement of large impurities
Authors: Nelli Diana
Published: February 2022

We employ metadynamics simulations at room temperature to study the diffusion of large single-atom impurities within otherwise pure icosahedral nanoparticles, for different bimetallic systems (Au-Co, Ag-Co, Ag-Ni, Au-Pt and Au-Rh) and icosahedral sizes. Our simulations reveal that the displacement of the impurity induces the formation of a vacancy in the central part of the structure, as already observed for small icosahedra of Au-Co and Ag-Cu, therefore confirming the generality of this peculiar diffusion process. At the largest size, a new collective displacement mechanism is identified alongside the diffusion of the impurity. For Au-Pt clusters, different diffusion pathways are observed, which are mediated by a partial deformation of the nanoparticle surface. This is due to the lack of stability of fivefold veritices in Pt icosahedral clusters. We prove that the stability of the icosahedral surface is an essential condition for the occurrence of the combined process of impurity diffusion and internal vacancy formation.
Strange Baryons in Nuclei and Neutron Stars
Authors: Tolos Laura
Published: February 2022

In this contribution we review the dynamics of hyperons with nucleons and nuclear matter, paying a special attention to hypernuclei. We also discuss the presence of hyperons in the inner core of neutron stars and the consequences for the structure of these compact stars.
The NICA Complex and the MPD experiment at JINR: status and physics potential
Authors: Kisiel Adam
Published: February 2022

The Multi-Purpose Detector is under construction at the Joint Institute for Nuclear Research in Dubna, as part of the NICA Accelerator Complex. The MPD Collaboration aims to study the phase diagram of QCD matter at maximum baryonic density, determine the nature of the phase transition between the deconfined and hadronic matter and search for the critical point. The combination of significant luminosity at NICA, collider geometry of the experiment and collision energies √SNN spanning the range of 4 to 11 GeV, where the transition from baryon to meson dominated matter is expected will allow MPD to provide unique insight into these questions. The status of the assembly of the detector in MPD Hall, as well as the progress in the production of MPD subdetectors will be reported on.

The design physics performance of the detector will be discussed with the emphasis on the measurements in the strangeness sector. Tracking and particle identification procedures will enable precise determination of spectra of identified hadrons, including hyperons and hypernuclei, with the possibility of differential measurements and total yield extraction. The quality of directed and elliptic flow determination will be discussed, with comparison to model expectations. The sensitivity of event-by-event fluctuations to the nature of the phase transition and the presence of a critical point will be given. The femtoscopic analysis for charged pions and kaons has shown sensitivity to first order and cross-over phase transitions in EoS seen for the vHLLE model. All those studies will be put in context of addressing outstanding questions on the properties of the region of the QCD phase diagram probed by heavy-ion collisions in the NICA energy range.
Off-of-equilibrium effects on Kurtosis Along Strangeness-Neutral Trajectories
Authors: Dore Travis , Karthein Jamie , Mroczek Debora , Parotto Paolo , Noronha-Hostler Jacquelyn , Ratti Claudia
Published: February 2022

The Beam Energy Scan program at the Relativistic Heavy Ion Collider (RHIC) is searching for the QCD critical point. The main signal for the critical point is the kurtosis of the distribution of proton yields obtained on an event by event basis where one expects a peak at the critical point. However, its exact behavior is still an open question due to out-of-equilibrium effects and uncertainty in the equation of state. Here we use a simplistic hydrodynamic model that enforces strangeness-neutrality, selecting trajectories that pass close to the critical point. We vary the initial conditions to estimate the effect of out-of-equilibrium hydrodynamics on the kurtosis signal.
Charm and Bottom quarks dynamics in heavy-ion collisions: RAA, anisotropic flows vn and their correlations to the bulk
Authors: Sambataro Maria Lucia , Plumari Salvatore , Sun Yifeng , Minissale Vincenzo , Greco Vincenzo
Published: February 2022

We describe the propagation of heavy quarks (HQs), charm and bottom, in the quark-gluon plasma (QGP) by means of a full Boltzmann transport approach including event-by-event fluctuations within a coalescence plus fragmentation hadronization. The non-perturbative dynamics of the interaction between HQs and plasma particles have been taken into account through a Quasi-Particle Model (QPM). We show that the resulting charm in-medium evolution is able to correctly predict simultaneously not only the experimental data for the average D-mesons RAA(pT) and v2,3(pT) at LHC energies but also the extension of the analysis to the event-shape engineeering tecnique that classify events according to magnitude of the second-order harmonic reduced flow vector q2. In the same scheme we show predictions for RAA(pT) of electrons from semi-leptonic B-mesons decays at top LHC energies. Our results entail a determination of Ds which is consistent with the lattice QCD calculations.
Triple nuclear collisions – a new method to explore the matter properties under new extreme conditions
Authors: Vitiuk O.V. , Pugatch V.M. , Bugaev K.A. , Panasiuk P.P. , Yakovenko N.S. , Grinyuk B.E. , Zherebtsova E.S. , Bleicher M. , Bravina L.V. , Taranenko A.V. , Zabrodin E.E.
Published: February 2022

We suggest to explore an entirely new method to experimentally and theoretically study the phase diagram of strongly interacting matter based on the triple nuclear collisions (TNC).We simulated the TNC using the UrQMD 3.4 model at the beam center of- mass collision energies √SNN = 200 GeV and √SNN = 2.76 TeV. It is found that in the most central and simultaneous TNC the initial baryonic charge density is about 3 times higher than the one achieved in the usual binary nuclear collisions at the same energies. As a consequence, the production of protons and Λ-hyperons is increased by a factor of 2 and 1.5, respectively. Using the MIT Bag model equation we study the evolution of the central cell in TNC and demonstrate that for the top RHIC energy of collision the baryonic chemical potential is 2-2.5 times larger than the one achieved in the binary nuclear collision at the same time of reaction. Based on these estimates, we show that TNC offers an entirely new possibility to study the QCD phase diagram at very high baryonic charge densities.
„Mir fehlte nur noch ein Puzzleteil zum Glück“ – Ausbildung zur Fachlehrkraft für Sonderpädagogik
Authors: Mischner Julia Marlene , Trullu Stephanie
Published: February 2022

Stephanie Trullu ist Ergotherapeutin. Jetzt arbeitet sie als Fachlehrerin für Sonderpädagogik und unterrichtet an einer Schule für Menschen mit Körperbehinderung. Was sie dazu bewogen hat, die therapeutische Arbeit gegen den Schulalltag zu tauschen, und wie ihre Ausbildung zur Fachlehrerin verlief, hat sie ergopraxis im Interview erzählt.
Die Praxis läuft – was nun? – Praxiserweiterung
Authors: Hiebl Sarah , Atzmüller Michael
Published: February 2022

Viele Praxisinhaber sind nach Praxisgründung irgendwann mit der Entscheidung konfrontiert, ob sie expandieren und Personal einstellen möchten oder nicht. Der Markt dazu ist da, denn die Wartezeiten für Therapieplätze explodieren. Mit einer Erweiterung ergeben sich jedoch Herausforderungen, und es kommt zu einer Veränderung im eigenen Rollenprofil.
Kinder in ihren Anliegen ernst nehmen – Foto-Interview
Authors: Kranz Florence
Published: February 2022

Kinder möchten mitbestimmen, an welchen Betätigungen sie gemeinsam mit ihren Ergotherapeut*innen arbeiten. Das Foto-Interview gibt ihnen die Möglichkeit, ihre Alltagsanliegen zu formulieren. Wie praktikabel ist das Assessment aus Sicht deutscher Ergotherapeut*innen? Mit dieser Frage haben sich Leonie Beitzel, Catharina Quadflieg, Laura Rattenstetter und Ricarda Söllner in ihrer gemeinsamen Bachelorarbeit auseinandergesetzt.
Bewegung visuell simulieren – Im Test: Therapiesystem IVS3
Authors: Haase Sarah , Heckmann Charlotte
Published: February 2022

Ein neues visuomotorisches Simulationstraining für Menschen nach Schlaganfall soll dabei helfen, die Bewegungskontrolle und -planung zu verbessern. Charlotte Heckmann und Sarah Haase berichten von ihren Erfahrungen mit dem Therapiesystem IVS3.
Psychiatrische Notfallaufnahmen und stationäre Aufenthaltsdauer vor und während der COVID-19-Pandemie in Deutschland
Authors: Fasshauer Jonathan Mathias , Bollmann Andreas , Hohenstein Sven , Mouratis Konstantinos , Hindricks Gerhard , Kuhlen Ralf , Meier-Hellmann Andreas , Broocks Andreas , Schomerus Georg , Stengler Katarina
Published: February 2022

Ziel der Studie Die Auswirkungen der COVID-19-Pandemie in 2020 auf die Anzahl der täglichen psychiatrischen Notfallaufnahmen und die stationäre psychiatrische Aufenthaltsdauer wurde mit Vorjahren verglichen.

Methodik In einer retrospektiven Studie wurden die 4 Quartale 2020 mehrerer psychiatrischer Kliniken in Deutschland mit den jeweiligen Quartalen von 2018 und 2019 statistisch verglichen.

Ergebnisse Insgesamt wurden 73 412 Fälle analysiert. Im 2. Quartal 2020 war die Zahl der täglichen Aufnahmen mit 59,1 signifikant niedriger im Vergleich zum Kontrollzeitraum mit 70,7 (Inzidenzratenverhältnis [95 %-Konfidenzintervall] 0,81 [0,69; 0,96]; p = 0,012). Die Aufenthaltsdauer war zwischen allen Quartalen 2020 im Vergleich zum Kontrollzeitraum numerisch, aber nicht signifikant unterschiedlich.

Schlussfolgerung Die COVID-19-Pandemie zeigt deutliche Auswirkungen auf die stationäre psychiatrische Versorgung. Zukünftig muss der Blick stärker auf die Notfall- und Krisenversorgung psychisch erkrankter Menschen gelenkt werden.
Synthetic Approaches for the Construction of Five- and Six-Membered Silaazacycles
Authors: Gao Lu , Song Zhenlei , Wang Wanshu
Published: February 2022

Silaazacycles (or azasilacycles), containing both nitrogen and silicon atoms, are appealing ring structures in the development of silicon-containing functional molecules. The development of general and efficient methods towards these motifs has therefore attracted considerable attention from synthetic chemists. This short review intends to highlight representative advances in the synthesis of five- and six-membered silaazacycles.

1 Introduction

2 Five-Membered Silaazacycles

2.1 Five-Membered Silaazacycles bearing a 1,2-N/Si Moiety

2.2 Five-Membered Silaazacycles bearing a 1,3-N/Si Moiety

3 Six-Membered Silaazacycles

3.1 Six-Membered Silaazacycles bearing a 1,2-N/Si Moiety

3.2 Six-Membered Silaazacycles bearing a 1,3-N/Si Moiety

3.3 Six-Membered Silaazacycles bearing a 1,4-N/Si Moiety

4 Conclusion
Iridium-Catalyzed Acceptorless Dehydrogenative Coupling of 2-Aminoarylmethanols with Amides or Nitriles to Synthesize Quinazolines
Authors: Shui Hongling , Zhong Yuhong , Luo Nianhua , Luo Renshi , Ouyang Lu
Published: February 2022

An efficient iridium-catalyzed acceptorless dehydrogenative coupling (ADC) reaction for the preparation of various quinazolines from 2-aminoarylmethanols and amides or nitriles had been developed. A wide range of substituted 2-aminobenzyl alcohols and (hetero)aryl or alkyl benzamides and nitriles were well compatible to afford various quinazolines in excellent yields. Merits of this new strategy are the high atom-economy, mild reaction conditions, and simple operation, and the methodology is suitable for a variety of substrates.
Incompleteness of moral choice and evolution towards fully autonomous AI
Authors: Hauer Tomas
Published: February 2022

Nowadays, it is fashionable to add the attribute “with artificial intelligence” to all possible devices, platforms and machines. The problem of ethical decision-making, viewed from the perspective of computer, technical and natural sciences, lies only in the complexity of the topic. AI scientists and developers basically proceed from the Turing machine model, assuming that a machine can be constructed to resolve any problems (including ethical decision-making issues) that can mechanically calculate a particular function if this function can be put into an algorithm. Thus, ethical decision-making is conceived as an abstract concept whose manifestation does not depend on the particular physical organism in which the algorithm takes place, nor on what it is made of. Whether from photons, mechanical relays, quantum fluctuations, artificial neurons or human nerve cells. If in practice, a sufficiently complex algorithm is built, it will also exhibit sufficiently complex behavior that can be characterized as ethical in the full sense of the word. This article reflects the main argument that if a task requires some form of moral authority when it is performed by humans, its full automation, transferring the same task to autonomous machines, platforms, and AI algorithms, necessarily implies the transfer of moral competence. The question of what this competence should include presupposes empirical research and reassessing purely normative approaches in AI ethics.
Terahertz frequency shifts due to multiphonon scattering in thiamin crystals containing hydrated ions
Authors: Takahashi Masae , Kowada Mitsuru , Matsui Hiroshi , Kwon Eunsang , Ikemoto Yuka
Published: February 2022

Terahertz resonances are capable of relaxing through multiphonon scattering because of the long lifetimes of excited vibrational states compared with the periods of lattice vibrations of a crystal. In this study, we examine the temperature-dependent frequency shifts in the frequency ranges of 20–90 and 200–600 cm−1 of thiamin crystals containing hydrated ions and provide evidence for multiphonon scattering. One-, two-, and three-phonon scattering are clearly observed in the form of discrete linear temperature coefficients of vibrational frequencies. Higher transition frequencies tend to cause more phonon scattering in the frequency range of 20–90 cm−1, while higher transition frequencies tend to cause less phonon scattering in the frequency range of 200–600 cm−1. The characteristic temperature parameter of the effective phonon taking part in the scattering processes is estimated to be 44.6 K, which is shared by different vibrational transitions, and the corresponding characteristic frequency is estimated to be 31.0 cm−1. Highly accurate solid-state first-principles calculations incorporating relativistic effects and dispersion corrections are performed, and the results show that the characteristic frequency is close to the lower limit of the calculated optical phonon frequencies, lying between the lowest two. The ratio of the vibrational transition frequency to the characteristic frequency is 1.6 for single-phonon scattering, 2.0 and 2.2 for two-phonon scattering, and 2.5 for three-phonon scattering in the frequency range of 20–90 cm−1. In the frequency range of 200–600 cm−1, the ratio is much higher than that in the frequency range of 20–90 cm−1 and is 9.4 to 16.4.
Innovative all-silicon based a-SiNx:O/c-Si heterostructure solar-blind photodetector with both high responsivity and fast response speed
Authors: Dong Hengping , Chen Kunji , Yang Huafeng , Ma Zhongyuan , Xu Jun , Li Wei , Yu Linwei , Huang Xinfan
Published: February 2022

The photoresponsivity and response speed are two key figures of merit for the photodetector (PD). According to the previous reports, there is an inherent contradiction between high photoresponsivity and fast response speed in normal photoconductive-type PDs. Facing the challenge of coordinating this inherent contradiction, we propose an innovative design idea, which employs a luminescent wide-bandgap (WBG) amorphous oxynitride (a-SiNx:O) film as an absorption layer combining with monocrystalline silicon (c-Si) as a carrier transport layer, to construct an all-silicon based a-SiNx:O/c-Si heterostructure photoconductive-type solar-blind photodetector (SBPD). Benefiting from the built-in electric field in the a-SiNx:O/c-Si heterojunction and good passivation at the SiNx:O/Si interface, the photogenerated carriers in the a-SiNx:O layer can be injected into the c-Si layer, which separates the carrier transport process from the carrier photogeneration/recombination process in the different layers. Since the transport process of injected carriers in the c-Si layer is much faster than their recombination process, the detector yields a large photoconductive gain, thus overcoming the above-mentioned inherent contradiction in normal photoconductive-type PDs, where both the defect-related carrier photogeneration/recombination process and carrier transport process occur in the same active layer. The designed SBPDs exhibit highlighted performance with both the high responsivity (R) of 4 × 103 A/W at 225 nm and the fast response speed of 4.3 µs. Compared to most other WBG semiconductor SBPDs, e.g., AlxGa1−xN, MgxZn1−xO, Ga2O3, and diamond, the advantages of the a-SiNx:O/c-Si heterostructure SBPD lie not only in adopting economic Si-based materials but also in manufacturing processes compatible with mature CMOS technology, thereby rendering it preferable for the development of cost-effective large-area SBPD arrays.
Study on a new method for generating a gas curtain in the gas-curtain launching
Authors: Hu Yu-bo , Yu Yong-gang , Zhang Xin-wei
Published: February 2022

To decrease the launching resistance of underwater guns, a new gas-curtain formation method is proposed based on the gas-curtain launching principle, which is setting up several rectangular grooves on the internal wall of the barrel to guide the gas flow to the front of the projectile and form a gas curtain. A three-dimensional unsteady two-phase flow model of the drainage is established. The formation and drainage characteristics of the gas curtain are studied under the different number of grooves with a constant injection area and 10 MPa injection pressure. The results indicate that the circumferential and radial converging effects of multi-gas jets are enhanced, but the axial expansion is enhanced first and then weakened when the number of grooves increases from 4 to 12. The vortex scale in the Taylor cavity increases with the increase in the number of grooves, but the distance moving downstream is shortened. The gas volume fraction in the tube increases with the increase in the number of grooves. However, the drainage efficiency of the gas curtain on the warhead increases first and then decreases with the increase in the number of grooves, while the change of the gas efficiency–cost ratio is just the opposite.
Powerful nanographite fault current limiter for smart grid
Authors: Lebedev S. G.
Published: February 2022

This article proposes the principally new type of fault current limiter—the contactless nanographite current limiter (CNGCL). The device works like a superconductor. At some critical value of the current, it abruptly falls to zero, at which point the resistance jumps up to 6 orders of magnitude. So far, the critical current is small about a few hundreds of mA. It is shown that an increase in the length of the contact pads up to 1 m will raise the switching current up to 1 kA, while the power dissipated by the CNGCL will be about 100 kW. The possibility of heat removal using water cooling using a chiller of appropriate capacity is being considered. The analysis shows that these measures will make it possible to create a competitive current limiter for smart grids based on CNGCLs.
On the polarity determination and polarity inversion in nitrogen-polar group III-nitride layers grown on SiC
Authors: Zhang Hengfang , Persson Ingemar , Papamichail Alexis , Chen -Tai , Persson Per O. Å. , Paskov Plamen P. , Darakchieva Vanya
Published: February 2022

We investigate the interfaces and polarity domains at the atomic scale in epitaxial AlN and GaN/AlN grown by hot-wall metal organic chemical vapor epitaxy on the carbon face of SiC. X-ray diffraction, potassium hydroxide (KOH) wet chemical etching, and scanning transmission electron microscopy combined provide an in-depth understanding of polarity evolution with the film thickness, which is crucial to optimize growth. The AlN grown in a 3D mode is found to exhibit N-polar pyramid-type structures at the AlN–SiC interface. However, a mixed N-polar and Al-polar region with Al-polarity domination along with inverted pyramid-type structures evolve with increasing film thickness. We identify inclined inversion domain boundaries and propose that incorporation of oxygen on the ⟨40–41⟩ facets of the N-polar pyramids causes the polarity inversion. We find that mixed-polar AlN is common and easily etched and remains undetected by solely relying on KOH etching. Atomic scale electron microscopy is, therefore, needed to accurately determine the polarity. The polarity of GaN grown on mixed-polar AlN is further shown to undergo complex evolution with the film thickness, which is discussed in the light of growth mechanisms and polarity determination methods.
Impact of inlet flow angle variation on the performance of a transonic compressor blade using NIPC
Authors: Chen Zeshuai , Xia Zhiheng , Luo Jiaqi
Published: February 2022

The impact of inlet flow variations on turbomachines is common in the real world, resulting in undesirable performance deteriorations in engineering. The origin of performance changes and how to evaluate the changes require to be investigated. On use of a polynomial chaos based surrogate model method and Monte Carlo simulation (MCS), performance impact considering the stochastic variations of the inlet flow angle for a transonic compressor rotor blade is studied, and the impact mechanisms are investigated by MCS-based statistical flow analysis. A detailed grid-independent study assisted by Richardson extrapolation is first presented to illustrate the reliability of numerical solutions. Then, the implementations of non-intrusive polynomial chaos employing an adaptive sparse grid are introduced. Uncertainty quantifications of adiabatic efficiency and mass flow rate changes of NASA Rotor 67 are achieved, and the effects of different distributions of inlet flow angle variation (IFAV) and different ranges of IFAV on the performance changes under different operation conditions are investigated. Finally, statistical analysis of flow solutions is performed by MCS. The spanwise distributions of the changes in adiabatic efficiency and mass flow rate at the outlet are presented. Moreover, the flow solutions on the blade-to-blade stream surfaces at different spans are statistically analyzed, and discussions are given to demonstrate the impact mechanisms of IFAV on performance changes.
Isotropic spin polarization in Heusler Co2FeAl thin films
Authors: Gao Qinwu , Li Zhihao , Ma Meiyang , Tu Jian , Wang Ruifeng , Liu Qi , Chen Zhendong , Zhang Yilin , Sun Yizhe , Ning Jiai , Yan Pengfei , Yan Yu , Lu Xianyang , Ruan Xuezhong , He Liang , Xu Yongbing
Published: February 2022

Spin polarization and the Gilbert damping, as the two key parameters of the magnetic materials for spintronic applications, were suggested to be inversely proportional to each other in a series of Heusler alloys. Recently, large anisotropic Gilbert damping was found in Co2FeAl thin films, implying that spin polarization may be also anisotropic. Here, we report an isotropic spin polarization with a constant value of 60% in a 20-nm Co2FeAl thin film with a B2 structure, using spin- and angle-resolved photoemission spectroscopy and time-resolved magneto-optical Kerr effect. Furthermore, this result was also supported by the ab initio calculations that the difference of the spin polarization between all the orientations is less than 1% for the Co2FeAl thin film. This finding provides profound insight into the spin polarization in Co2FeAl alloys.
The influence of in situ ozone on structure and transport properties for perovskite stannate La-doped BaSnO3 epitaxial films
Authors: Liu Ningtao , Zhang Jinfu , Chen Li , Wang Liu , Wu Simiao , Zhang Tan , Wang Wei , Wang Zilong , Zhang Wenrui , Ye Jichun
Published: February 2022

Here we investigate the influence of in situ ozone treatment on structure and carrier transport in La-doped BaSnO3 BLSO) films. It is found that introducing ozone during the film growth significantly inhibits the formation of oxygen vacancies and the occurrence of Sn2+ ions. The amount of oxygen vacancies decreases consistently with the increase of the ozone content, which further increases the in-plane lattice constant along with the relief of the in-plane compressive strain. More importantly, the reduction of oxygen vacancies gives rise to the augment of the threading dislocation density in the BLSO films, leading to the deterioration of carrier mobility. These findings demonstrate that the existence of Sn2+ ions does not apparently suppress the electron mobility in BLSO films, and the presence of oxygen vacancies is beneficial for reducing the density of threading dislocations, facilitating the mobility enhancement. All these findings would be beneficial for understanding the role of oxygen vacancy in carrier transport properties and for further optimizing the mobility of BLSO films.
Role of phase-difference between two adjacent rectangular synthetic jet actuators in active control of flow over a rounded ramp
Authors: Asgari Ehsan , Tadjfar Mehran
Published: February 2022

In the current study, the role of phase-difference between signals of two adjacent synthetic jet actuators (SJAs) in active control of flow over a rounded ramp geometry has been investigated. In order to accurately predict the separation and reattachment locations, wall-resolved large eddy simulation has been utilized to capture the locations of separation and reattachment. The two adjacent SJAs were placed upstream of the separation point. Six phase-differences between the two SJAs were considered, and two momentum coefficients were applied. First, the role of phase-difference in active flow control of a separation bubble behind a ramp-down region was investigated. Furthermore, the impact of an increased momentum ratio on the size and length of the separation zone was investigated to assess the effectiveness of phase-difference with respect to a higher velocity ratio. The effect of increased momentum ratio on the wall pressure fluctuations was also explored. As the second objective of this study, the flow and turbulent features were discussed to unveil the SJA actuation impact on the downstream flow. The time-averaged velocity and turbulent kinetic energy profiles and the turbulent production were examined and compared to the uncontrolled baseline case. It was found that a higher velocity ratio tremendously increased the turbulent energy before the separation point, while further downstream, the level of turbulent energy was uncoupled from the SJA momentum coefficient. Our study showed that by increasing the momentum ratio, the role of phase-difference in reducing the separation thickness lessened. Nevertheless, applying either a positive or a negative phase-difference of pi/2 still postponed the separation point.
Early stage of externally driven filling of viscous fluids within a microfluidic pore-doublet network
Authors: Duan Cong , Yang Xiaohan , Jiang Shaokun , Zhu Chunying , Ma Youguang , Fu Taotao
Published: February 2022

The early stage of active capillary filling of viscous fluids in a pore-doublet network is studied experimentally. The effects of operating conditions and fluid properties on the filling process are revealed. In the straight channel, the evolution of the meniscus with time transferred from a linear stage to a power-law stage is due to the interplay among the inertial force, capillary force, and viscous force. An expression of the filling rate is proposed at the present startup of the capillary filling flow. With the addition of surfactant sodium dodecyl sulfate (SDS), the power-law stage of the penetration process turns into another linear stage. In symmetrical Y-shaped microchannels, increasing the capillary number or liquid viscosity or adding surfactant SDS to the solutions effectively reduces the difference in liquid position between the branches. A larger Ohnesorge number leads to more uniform and stable penetration.
Effects of the path history on inertial particle pair dynamics in the dissipation range of homogeneous isotropic turbulence
Authors: Shim Jeongbo , You Donghyun
Published: February 2022

The relationship between inertial particle pair dynamics in the dissipation range and local turbulence characteristics is investigated using direct numerical simulations in homogeneous isotropic turbulence at a Reynolds number of 110 based on the Taylor microscale. Seventeen million sub-Kolmogorov-sized particles with Stokes numbers of 0.5, 1.0, 1.5, and 2.0 are tracked backward in time to investigate the formation of the relative velocity of inertial particles in the dissipation range. The numerical experiment shows that particle pairs take different paths and sample different underlying flows depending on the intensity of the local turbulence activity at final locations where the distance between particles is much smaller than the Kolmogorov length scale. Taking different paths depending on the intensity of the local turbulence activity is described by the sling time, which is defined as the time when particle pairs are slung out from the underlying flow. Particle pairs with shorter sling time values than the characteristic time scale of particles are detached from the dissipation range of flow and approach each other in a ballistic fashion. In contrast, the large-scale flow guides particle pairs with longer sling time than the characteristic time scales. In particular, particle pairs forming caustics with the same sling time are detached from similar flows regardless of the magnitude of particle relative velocities. Samplings of similar flows at sling moments cause the scaling relationship between relative velocities of particles and sling time. These behaviors of particle pairs, especially for pairs with caustics in relative velocities, are also observed in the range of considered Stokes numbers. The relationship between the intensity of the local turbulence activity and the paths taken by particles highlights the importance of considering a preferential sampling of flow in understanding inertial particle pair dynamics.
Temperature dependence of inertial pumping in microchannels
Authors: Kornilovitch Pavel E. , Cochell Tyler , Govyadinov Alexander N.
Published: February 2022

Inertial pumping is a promising new method of moving fluids through microchannels but many of its properties remain unexplored. In this work, inertial flow rates are investigated for different channel lengths, operating temperatures, and resistor pulse energies. The flow in closed channels is visualized by adding fluorescent tracer beads to the test fluid (pure water). A robust methodology of extracting flow rates from high-resolution video recordings is developed. Flow rates are found to scale inversely with the channel length. The observed dependence is explained based on a simple phenomenological “kick” model of inertial pumping. Flow rates are also fitted to the more fundamental one-dimensional model of inertial pumping from which the intrinsic drive bubble strength is extracted. The measured flow rates vary strongly with temperature. For well-developed drive bubbles, flow rates at T=70 °C are about 12× higher than at T = 30 °C. Three separate effects contribute to increasing flow rates at high temperatures: (i) lower viscosity of the test fluid, (ii) a stronger drive bubble, and (iii) increasing mechanical efficiency of the pump, i.e., better conversion of the drive bubble strength to unidirectional post-collapse kick. Relative contributions of the three effects are quantified. The energy dependence of flow rates exhibits a clear saturation behavior. The bubble strength is fitted to a phenomenological saturation model. In the end, a complete predictive length-temperature-energy model of flow rates is constructed. The observed strong temperature dependence of inertial pumping should be considered when designing microfluidic workflows. It also highlights the need for integrated flowmeters that could stabilize complex flow patterns via sensory feedback.