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Effect of Different Calcination Temperatures and Post Annealing on the Properties of Acetic Acid Based Sol-Gel (Na_(0.5)K_(0.5))NbO_3(NKN) Thin Films

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journal of Materials Science & Technology 2013年第2期29卷 142-148页

作者： sebastian Wiegand Stefan Flege Olaf Baake Wolfgang Ensinger Materials Analysis Group Department of Materials and Geosciences Technische Universitt Darmstadt Petersenstrasse 23 64287 Darmstadt Germany

（Na0.5K0.5）NbO3 （NKN） lead free thin films were synthesized by means of an acetic acid based sol-gel process on Pt/Ti/SiO2/Si substrates. Na-acetate, K-acetate and Nb-pentaethoxide were used as metal precursors and acetic acid as the solvent. The effect of different calcination temperatures on the properties of the NKN films was investigated by X-ray diffraction, scanning electron microscopy, leakage current and hysteresis measurements. Low calcination temperatures led to low currents at high electric fields whereas high calcination temperatures led to low currents at low electric fields. Based on these findings calcination at low temperature was combined with a post annealing treatment. Low leakage currents of 4×10^-4 A/cm2 at 150 kV/cm and 2Pr and 2Ec values of 28 μC/cm2 and 150 kV/cm, respectively, could be obtained. All films were single phase NKN with random crystal orientations and no crack or pore formation was visible on the surface.

关键词： Sol-gel process (Na0.5K0.5)NbO3 Thin film Perovskite Lead-free Piezo material

Computational studies on the seismic response of the State Route 99 bridge in Seattle with SMA/ECC plastic hinges

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Frontiers of Structural and Civil Engineering 2019年第1期13卷 149-164页

作者： jiping GE M.Saiid SAIIDI sebastian VARELA School of Urban Construction and Safety Engineering Shanghai Institute of TechnologyShanghai 201418China Department of Civil and Environmental Engineering University of NevadaRenoNV 89557USA Structural Engineering Group Freese and Nichols Inc.Fort WorthTX 76109USA

This paper reports a computational study on the seismic response of a three-span highway bridge system incorporating conventional and novel substructure details for improved seismic *** bridge has three continuous spans supported by two single-column piers and integral abutments founded on drilled *** will be the first full-scale highway bridge to use superelastic shape memory alloy bars (SMA)and engineered cementitious composite (ECC)to mitigate column plastic hinge damage and minimize residual displacements after a strong earthquake. A three-dimensional computational model capturing the nonlinear constitutive response of the novel materials and the effects of dynamic soil-structure interaction was developed to assess the seismic response of the bridge in finite-element software *** versions of the same bridge were analyzed and compared,one with conventional cast-in-place reinforced concrete columns,and the other with top plastic hinges incorporating Nickel-Titanium (NiTi)SMA reinforcing bars and *** novel SMA/ECC plastic hinges were found to substantially reduce damage and post-earthquake residual displacements in the bridge substructure,but led to larger maximum drifts relative to the bridge with conventional reinforced concrete plastic *** analysis results suggested that the novel plastic hinges could lead to improved post-earthquake serviceability of bridges after intense earthquakes.

关键词： seismic design analytical simulation near-fault earthquakes shape memory alloy engineered cementitious composite self-centering

Multi-material additive manufacturing-functionally graded materials by means of laser remelting during laser powder bed fusion

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Frontiers of Mechanical Engineering 2023年第4期18卷 183-193页

作者： Alexander SCHMIDT Felix jENSCH sebastian HÄRTEL Chair of Hybrid Manufacturing Brandenburg University of TechnologyCottbus 03046Germany

Many processes may be used for manufacturing functionally graded *** them,additive manufacturing seems to be predestined due to near-net shape manufacturing of complex geometries combined with the possibility of applying different materials in one *** adjusting the powder composition of the starting material layer by layer,a macroscopic and step-like gradient can be *** further improve the step-like gradient,an enhancement of the in-situ mixing degree,which is limited according to the state of the art,is *** this paper,a novel technique for an enhancement of the in-situ material mixing degree in the melt pool by applying laser remelting(LR)is *** effect of layer-wise LR on the formation of the interface was investigated using pure copper and low-alloy steel in a laser powder bed fusion *** cross-sectional selective electron microscopic analyses were carried *** applying LR,the mixing degree was enhanced,and the reaction zone thickness between the materials was ***,an additional copper and iron-based phase was formed in the interface,resulting in a smoother gradient of the chemical composition than the case without *** Marangoni convection flow and thermal diffusion are the driving forces for the observed effect.

关键词： multi-material additive manufacturing(MMAM) functionally graded materials(FGMs) laser powder bed fusion(L-PBF) laser remelting(LR) pure copper

Free-space interferometer design for optical frequency dissemination and out-of-loop characterization below the 10^(-21)-level

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Photonics Research 2023年第6期11卷 1113-1124页

作者： THOMAS jÜRSS GESINE GROSCHE sebastian KOKE Physikalisch-Technische Bundesanstalt 38116 BraunschweigGermany

For improving the performance of optical frequency dissemination and the resolution of its out-of-loop(OOL)characterization,we investigate a compact free-space interferometer design in which a monolithic assembly forms the reference *** interferometer designs are realized,and their environmental sensitivity is analyzed based on the properties of the materials *** elucidate that in these designs the temperature sensitivities of the out-of-loop signal paths are greater than for the reference *** the estimated temperature-variation-induced frequency transfer errors are observed to be the relevant limitation,the out-of-loop characterization signal can be regarded as a trustworthy upper limit of the frequency transfer error to a remote *** demonstrate a fractional frequency transfer uncertainty and OOL characterization resolution of≤2.7×10^(-21)over many measurement *** a value of(0.23±1.07)×10^(-22)the weighted mean offset is significantly below the best reported results so far.

关键词： characterization fractional limit

Combination of OCT and Raman spectroscopy for improved characterization of atherosclerotic plaque depositions

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Chinese Optics Letters 2017年第9期15卷 31-35页

作者： Kokila Egodage Christian Matthaus sebastian Dochow Iwan W.Schie Carmen Hardtner Ingo Hilgendorf jürgen Popp Leibniz Institute of Photonic Technology Albert Einstein Straβe 9Jena 07745Germany Institute of Physical Chemistry and Abbe Center of Photonics Friedrich-Schiller-UniversityJena 07743Germany University Heart Center Freiburg Department of Cardiology and Angiology IFaculty of MedicineUniversity of FreiburgGermany

The biochemical composition of atherosclerotic plaques is closely related to plaque stability and, therefore, to the associated risk of plaque evolution and rupture. Combinations of current imaging modalities, such as optical coherence tomography（OCT） with spectroscopic methods, therefore offer the possibility of concurrently obtaining morphological as well as chemical information. Raman spectroscopy is one of the most promising techniques that can be combined with intravascular imaging modalities. A microscopy setup merging both techniques has been applied to characterize plaque depositions of a human aorta affected by the disease. Calcified depositions were clearly identified and subsequently confirmed by histopathology.

关键词： Combination of OCT and Raman spectroscopy for improved characterization of atherosclerotic plaque depositions

First Record of the Gekkonid Genus Cnemaspis Strauch, 1887 from Gunung Mulu National Park, Northern Sarawak, East Malaysia may Represent an Undescribed Species

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Asian Herpetological Research 2014年第3期5卷 209-212页

作者： André KOCH sebastian SCHULZ Zoological Research Museum Alexander Koenig (ZFMK) Leibniz-Institute for terrestrial Biodiversity

We provide confirmed photographic evidence for the previously overlooked occurrence of the polyphyletic Asian gecko genus Cnemaspis from Gunung Mulu National Park, the world-renowned UNESCO natural heritage site in northern Sarawak, East Malaysia. This new record from Sarawak province represents a remarkable range extension for Cnemaspis cf. kendallii by 550 km to the northeast and denotes the most northern occurrence of the genus in Borneo. Our new finding makes it very likely that these gekkonid lizards also inhabit appropriate limestone karst habitats in adjacent Sabah, Brunei, and Kalimantan. Given the visible differences in the Mulu specimen compared to those from the remaining distribution range on Borneo and the Malaysian Peninsula together with the fact that numerous Cnemaspis species are restricted to small areas, it seems plausible that another undescribed, rather cryptic and possibly locally endemic Bornean species is involved. Lastly, the new record contributes to the importance of the Mulu National Park as a major conservation area in East Malaysia of international concerns.

关键词： Southeast Asia Borneo Gekkonidae herpetofaunal diversity new record

Design and Construction Challenges for a Hybrid Air and Thermal Energy Storage System Built in the Post-Mining Shaft

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journal of Thermal Science 2022年第5期31卷 1302-1317页

作者： WANICZEK sebastian OCHMANN jakub BARTELA Lukasz RULIK sebastian LUTYNSKI Marcin BRZUSZKIEWICZ Michal KOLODZIEj Konrad SMOLNIK Grzegorz jURCZYK Michal LIPKA Marian Energoprojekt-Katowice SA Katowice40-159Poland Department of Power Engineering and Turbomachinery Silesian University of TechnologyGliwice44-100Poland Department of Mining Silesian University of TechnologyGliwice44-100Poland Department of Geomechanics and Underground Construction Silesian University of TechnologyGliwice44-100Poland

Compressed Air Energy Storage(CAES)is one of the methods that can solve the problems with intermittency and unpredictability of renewable energy sources.A side effect of air compression is a fact that a large amount of heat is generated which is usually *** the development of CAES systems,the main challenge,apart from finding suitable places for storing compressed air,is to store this heat of compression process so that it can be used for heating the air directed to the expander at the discharging *** paper presents the concept of a hybrid compressed air and thermal energy storage(HCATES)system,which may be a beneficial solution in the context of the two mentioned *** novel concept assumes placing the thermal energy storage(TES)system based on the use of solid storage material in the volume of the post-mining shaft forms a sealed air pressure *** of proposed systems within heavily industrialized agglomerations is a potential pathway for the revitalization of post-mine *** potential of energy capacity of such systems for the Upper Silesian region could exceed the value of 10 *** the paper,the main construction challenges related to this concept are *** issues related to the possibility of storing air under high pressure in the shaft from the view of the rock mass strength are *** overall concept of the TES system installation solution in the shaft barrel is *** basic problems related to heat storage in the cylindrical TES system with a non-standard structure of high slenderness are also *** numerical calculations were based on the results of experiments performed on a laboratory stand,the geometry of which is to reflect the construction of a TES tank in a post-mining *** article presents the results of numerical analysis showing the basic aspects related to difficulties that may occur at the construction stage and during the operation of the proposed HCATES *** paper

关键词： energy compressed air energy storage thermal energy storage post-mine areas revitalization structure analysis

Impact of Adrenaline or Cortisol Injection on Meat Quality Development of Merino Hoggets

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journal of Integrative Agriculture 2013年第11期12卷 1931-1936页

作者： Dario G Pighin sebastian A Cunzolo Maria Zimerman Adriana A Pazos Ernesto Domingo Anibal j Pordomingo Gabriela Grigioni Institute of Food Technology National Institute of Agricultural Technology(INTA)De Los Reseros y Las CabaasMorón 1708Argentina National Council of Scientific and Technological Research-CONICET Av.Rivadavia 1917Buenos Aires 1033Argentina Faculty of Agricultural and Food Sciences University of Moron Experimental Station-INTA Bariloche Modesta Victoria 4450San Carlos de Bariloche Río Negro 8400Argentina Institute of Food Technology National Institute of Agricultural Technology(INTA)De Los Reseros y Las Caba asMorón 1708Argentina Experimental Station-INTA Anguil Ruta Nacional No 5 Km.580(6326)La Pampa 6326Argentina

Increased levels of stress hormones in the muscle could lead to post mortem metabolic/structural modiifcations that could be relfected on meat quality. The present study investigated the metabolic effect of either adrenaline or cortisol injected into lambs in order to obtain an animal model of acute stress. Results showed that adrenaline or cortisol injection lead to glucose metabolism and muscle temperature increase. Muscle pH immediately post mortem was affected by adrenaline treatment. Water holding capacity （WHC） of fresh muscle, ifnal muscle pH and temperature registered at 24 h post mortem were not affected by injected hormones. Hardness and adhesiveness of LD muscle evaluated 3 d post mortem tended to increase as a result of adrenaline or cortisol injection. Results demonstrated that injected hormones were able to affect the post mortem muscle biochemistry and the pH/T curve independently of ifnal muscle pH.

关键词： stress hormones muscle metabolism meat quality

A Comprehensive Review of COVID-19 Virology, Vaccines, Variants, and Therapeutics

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Current Medical Science 2021年第6期41卷 1037-1051页

作者： Lauren Forchette William sebastian Tuoen LIU Department of Biomedical Sciences West Virginia School of Osteopathic Medicine400 Lee Street NorthLewisburgWest Virginia 24901USA

Summary:Severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),the causative pathogen of Ihe coronavirus disease 2019(COVID-19),has caused more than 179 million infections and 3.8 million deaths *** the past year,multiple vaccines have already been developed and used,while some others are in the process of being ***,the emergence of new mutant strains of SARS-CoV-2 that have demonstrated immune-evading characteristics and an increase in infective capabilities leads to potential ineffectiveness of the vaccines against these *** purpose of this review article is to highlight the current understanding of the immunological mechanisms of the virus and vaccines,as well as to investigate some key variants and mutations of the virus driving the current pandemic and their impacts on current management *** also discussed new technologies being developed for the prevention,treatment,and detection of *** this paper,we thoroughly reviewed and provided crucial information on SARS-CoV-2 virology,vaccines and drugs being used and developed for its prevention and treatment,as well as important variant *** review paper will be beneficial to health care professionals and researchers so they can have a better understanding of the basic sciences,prevention,and clinical treatment of COVID-19 during the *** paper consists of the most updated information that has been available as of june 21,2021.

关键词： severe acute respiratory syndrome coronavirus 2 coronavirus disease 2019 vaccines-variant strains antiviral therapy