bluuebunny/crossref_metadata_2025 huggingface dataset:
Hydrogen-related defects measured by infrared spectroscopy in multicrystalline silicon wafers throughout an illuminated annealing process
Authors: Weiser Philip M. , Monakhov Eduard , Haug Halvard , Wiig Marie Syre , Søndenå Rune
Published: February 2020

Hydrogen (H) is thought to be strongly involved in the light and elevated temperature-induced degradation observed predominantly in p-type silicon wafers, but the nature of the defect or defects involved in this process is currently unknown. We have used infrared (IR) spectroscopy to detect the vibrational signatures due to the H–B, H–Ga, and H2*(C) defects in thin, hydrogenated, p-type multicrystalline silicon wafers after increasing the optical path length by preparation and polishing the edges of a stack of wafers. The concentrations of the H–B and H–Ga acceptor complexes are reduced to 80% of their starting values after low intensity (5 mW/cm2) illumination at room temperature for 96 h. Subsequent high intensity illumination (70 mW/cm2) at 150 °C for 7–8 h further decreases the concentrations of these defects; to ∼40% (H–B) and ∼50% (H–Ga) of their starting values. Our results show that, with careful sample preparation, IR spectroscopy can be used in conjunction with other techniques, e.g., quasisteady-state photoconductance, to investigate the involvement of different H-related point defects on degradation in solar-grade silicon wafers.
Maximising the value of clinical registry information through integration with a health service clinical governance framework: a case study
Authors: Ahern Susannah , Feiler Robert , Sdrinis Susan
Published: February 2020

This initiative sought to identify unit participation in clinical registries within a large metropolitan health service and to develop approaches to integration of registry reporting within the organisational clinical governance framework to maximise potential quality improvement benefits. The initiative, led by the Medical Services Department at Alfred Health, initially involved identifying health service participation in clinical registries via a range of mechanisms, including one-on-one meetings with clinical registry investigators. In conjunction with the Clinical Governance Unit, tools to summarise and track clinical registry information at Alfred Health over time were developed and piloted. Alfred Health identified 69 clinical registries in which its units participated. These were heterogeneous in terms of clinical area and purpose, as well as the nature and frequency of reporting. Engagement with clinicians led to the establishment of a registry interest group, a calendar of clinical quality registry reports, and a guideline and reporting template and dashboard. Clinician engagement and medical leadership were critical to the development of this initiative. The reporting tool and dashboard have had initial success, with long-term success ultimately being measured by the routine incorporation of registry outcomes into clinical governance reporting over time.
What is known about the topic?Health service clinical governance systems require the collection, analysis and ongoing monitoring of clinical performance and quality improvement information. These data may be from internally derived clinical indicators or from external datasets, such as clinical registries. However, although clinical registries have traditionally provided information at the unit level, mechanisms to systematically incorporate these clinical measures into health service clinical governance systems have been lacking.
What does this paper add?This paper provides a case study of the steps taken by one large health service to identify, engage clinicians and incorporate disease-specific clinical registry indicators into its organisational clinical governance framework. It highlights the complexity of the task through the time taken to identify, translate and summarise key clinical information into a format suitable for organisational committee reporting.
What are the implications for practitioners?This paper highlights to health service managers the importance of initial and ongoing engagement of clinicians in the development of a shared approach to organisational use of clinical registry data. It outlines potential steps that can be taken within a health service to engage clinicians in sharing registry information, and processes that can assist in systematically incorporating registry information into actionable organisational-level reporting as part of clinical governance.
Australian corticolous myxomycetes: models of distribution and development
Authors: Wellman Peter
Published: February 2020

This paper presents an integrated model of the variation over a continental landmass of myxomycetes, a single-celled organism in the phylum Amoebozoa. Bark samples were collected on long traverses across Australia, and cultivated in Petri dishes by the moist chamber technique to obtain large assemblages of common species. The results of this survey and previous surveys are consistent with there being four major myxomycete assemblages: Tropical, Northern Arid, Southern Arid and Temperate. Where mapped, these species assemblage regions are consistent with the Australian phytogeographical regions. The myxomycetes differ between arid and non-arid areas; the arid areas have slightly higher productivity per wetting event, with members of the Physarales and Liceales relatively important and the Stemonitidales, Trichiales and Cribrariales less important. When the bark samples are placed in a moist culture there is a myxomycete growth cycle and then the population declines to resting phases. The population increase during a growth phase can be modelled by a linear plot of log(abundance) against species rank, where abundance is total harvested spore volume of a species. The population decline appears to be linear from two weeks after watering, declining to negligible activity 4 weeks after watering.
Phylogeny of Echiura updated, with a revised taxonomy to reflect their placement in Annelida as sister group to Capitellidae
Authors: Goto Ryutaro , Monnington James , Sciberras Marija , Hirabayashi Isao , Rouse Greg W.
Published: February 2020

Echiura (commonly called spoon worms) are derived annelids that have an unsegmented sausage-shaped body with a highly extensible anterior end (i.e. a proboscis). Echiura currently contains two superfamilies: Echiurioidea (with Echiuridae, Urechidae and Thalassematidae) and Bonellioidea (with Bonelliidae, and Ikedidae). Ikedidae contains only Ikeda, which is distinctive in having a huge trunk, a highly elongate proboscis with stripes or dots, and numerous gonoducts. A recent molecular phylogeny of Echiura recovered Ikedidae as the sister group to Bonelliidae. However, due to relatively low support values for the monophyly of Bonelliidae, this relationship remains problematic. In this study, we reinvestigated the relationship of Bonelliidae and Ikedidae using an expanded dataset with more taxa and genes. In contrast to the previous results, our analyses strongly support that Ikeda is nested within Bonelliidae due to the placement of Maxmuelleria. On the basis of this result, we synonymise Ikedidae with Bonelliidae and transfer Ikeda to the latter, the diagnosis of which is amended. In addition, we synonymise Urechidae with its sister group Echiuridae because they share the synapomorphy of having anal chaetae rings. Furthermore, considering that recent phylogenetic studies have consistently recovered Echiura as the sister group to Capitelliidae within Annelida, we drop the rank of the echiuran clade to family-level and propose a revised classification: Thalassematidae with two subfamilies, Thalassematinae (with two tribes Echiurini and Thalassematini) and Bonelliinae. In addition, we identified a sample collected from the deep sea (~1820 m) of Monterey Bay, California, based on its molecular data. This terminal unexpectedly formed the sister group to the eight genera of Thalassematini, most members of which are inhabitants of littoral zones.
Supralittoral pseudoscorpions of the genus Garypus (Pseudoscorpiones : Garypidae) from the Indo-West Pacific region, with a review of the subfamily classification of Garypidae
Authors: Harvey Mark S. , Hillyer Mia J. , Carvajal Jose I. , Huey Joel A.
Published: February 2020

The pseudoscorpions of the genus Garypus L. Koch are restricted to seashore habitats where they occupy supralittoral and littoral zones primarily in tropical and subtropical areas. Few species have been recorded from the Indo-West Pacific region, and this project was devised to produce a review of the species found in museum collections and to test the relationships of the various garypid genera using a molecular analysis and an assessment of their morphology. A new subfamily classification is proposed with the subfamilies Garypinae, including Garypus and the new genus Anchigarypus Harvey (type species Garypus californicus Banks), and the Synsphyroninae for the other genera (Ammogarypus Beier, Anagarypus Chamberlin, Elattogarypus Beier, Eremogarypus Beier, Meiogarypus Beier, Neogarypus Vachon, Paragarypus Vachon, Neogarypus Vachon, Synsphyronus Chamberlin, and Thaumastogarypus Beier). The species-level revision of Garypus provides evidence for at least 14 species, most of which are known from only single localities. The following species are redescribed: G. insularis Tullgren from the Seychelles, G. krusadiensis Murthy & Ananthakrishnan from India and Sri Lanka, G. longidigitus Hoff from Queensland, Australia, G. maldivensis Pocock from the Maldives, G. nicobarensis Beier from the Nicobar Islands and G. ornatus Beier from the Marshall Islands. The holotype of G. insularis is a tritonymph, and not therefore readily identifiable. Nine new species are described: G. latens Harvey, sp. nov., G. malgaryungu Harvey, sp. nov., G. necopinus Harvey, sp. nov., G. postlei Harvey, sp. nov., G. ranalliorum Harvey, sp. nov. and G. weipa Harvey, sp. nov. from northern Australia, G. dissitus Harvey, sp. nov. from Cocos-Keeling Island, G. reong Harvey, sp. nov. and G. yeni Harvey, sp. nov. from Indonesia. A further possible new species from Queensland is described but not named, as it is represented by a single tritonymph. The subspecies of the Caribbean species G. bonairensis Beier are elevated to full species status: G. bonairensis, G. realini Hummelinck and G. withi Hoff. We supplement the descriptions with sequence data from five specimens from four species of Garypus and two species of Anchigarypus, and find COI divergence levels of 7–19% between Garypus species. http://zoobank.org/References/16463E29-6F13-4392-9E41-46A4312C852B
The Wedderburn Meteorite revisited
Authors: Birch William D.
Published: February 2020

The Wedderburn meteorite from Victoria is a small nickel-rich iron belonging to the rare sLH subgroup of the IAB complex. Donated to the Mines Department in 1950, it came to public attention in 1953 when the initial description was published by Dr Austin Edwards in the Proceedings of the Royal Society of Victoria. Since then, pieces of the meteorite have been distributed to major institutions in Europe and North America, where leading researchers have investigated the meteorite’s unusual chemistry, mineralogy and microtexture in great detail. The recent approval of a new iron carbide mineral named edscottite, with the formula Fe5C2, in Wedderburn has prompted this review of the meteorite’s history, from its discovery to its current classification status.
Describing buoys from the perspective of discourse markers
Authors: Gabarró-López Sílvia
Published: February 2020

This paper provides a description of the distribution of buoys across genres and of their possible functions as discourse markers in French Belgian Sign Language. We selected a sample of dialogic genres – argumentative, explanatory, narrative, and metalinguistic – produced by different signers from the LSFB Corpus. In our dataset, buoys are unequally distributed across genres, and list and fragment buoys are the most frequent. Apart from a pointer and a point buoy, only some list buoys have discourse-marking functions, including enumeration, alternative, and addition. On the basis of the distribution of all types of buoys, the narrative dialogic genre is the most different as compared to the other three genres. It is characterized by a lower frequency of list buoys and a higher frequency of fragment buoys. When focusing on discourse-marking buoys, the explanatory genre attracts the highest number of tokens, which we relate to the higher degree of preparation as compared to the other genres.
To shift or not to shift
Authors: Hübl Annika , Maier Emar , Steinbach Markus
Published: February 2020

There are two main competing views about the nature of sign language role shift within formal semantics today:Quer (2005)and Schlenker (2017a,b), following now standard analyses of indexical shift in spoken languages, analyze it as a so-called ‘monstrous operator’, whileDavidson (2015)andMaier (2017), following more traditional and cognitive approaches, analyze it as a form of quotation. Examples of role shift in which some indexicals are shifted and some unshifted pose a prima facie problem for both approaches. In this paper, we propose a pragmatic principle of attraction to regulate the apparent unshifting/unquoting of indexicals in quotational role shift. The analysis is embedded in a systematic empirical investigation of the predictions of the attraction hypothesis for German Sign Language (DGS). Results for the first and second person pronouns (ix1andix2) support the attraction hypothesis, while results forhereare inconclusive.
Biosynthesis of the widely distributed hydrocarbon (Z,Z)-6,9-heptadecadiene in astigmatid mites
Authors: Moriyama Daisuke , Shimizu Nobuhiro
Published: February 2020

Using a crude enzyme solution prepared from astigmatid mites, the conversion reaction to (Z,Z)-6,9-heptadecadiene (6,9-C17) using linoleyl aldehyde (LAld) as a substrate was successful. The mass spectrum of the reaction product using 13C-labeled LAld as a substrate could be assigned as 13C-labeled 6,9-C17. Unlike the findings in other species, the decarbonylase derived from mites did not require a coenzyme.
Association of sudden sensorineural hearing loss with chronic periodontitis
Authors: Panda Khirod Chandra , Bhuyan Lipsa , Ramchander Puppala Venkat
Published: February 2020

Objective:

To find the overall association of sudden sensorineural hearing loss (SSNHL) and chronic periodontitis (CP) between case and control among the patients with comorbidities like diabetes mellitus, hypertension and obesity.

Design:

Case-control study comprising 351 subjects with SSNHL and 1101 controls without SSNHL. Both the case and control groups had the individuals with CP and/or CP with diabetes mellitus, hypertension and obesity.

Results:

We have shown the significant association of SSNHL with CP (p < .05; odd ratio 3.565, 95% confidence interval = 2.566–4.953). The comorbidities stratified analysis revealed a significantly higher risk of SSNHL with CP in the presence or absence of diabetes mellitus, hypertension and obesity (p < .05).

Conclusion:

We found a significant association of SSNHL with CP. Further, we highlighted the exclusive association of SSNHL and CP, even in cases of CP with or without other comorbidities like diabetes mellitus, hypertension and obesity. More studies must be conducted only with cases having SSNHL and CP for these results to be supported.
Tumor-derived soluble CD155 inhibits DNAM-1–mediated antitumor activity of natural killer cells
Authors: Okumura Genki , Iguchi-Manaka Akiko , Murata Rikito , Yamashita-Kanemaru Yumi , Shibuya Akira , Shibuya Kazuko
Published: February 2020

CD155 is a ligand for DNAM-1, TIGIT, and CD96 and is involved in tumor immune responses. Unlike mouse cells, human cells express both membranous CD155 and soluble CD155 (sCD155) encoded by splicing isoforms of CD155. However, the role of sCD155 in tumor immunity remains unclear. Here, we show that, after intravenous injection with sCD155-producing B16/BL6 melanoma, the numbers of tumor colonies in wild-type (WT), TIGIT knock-out (KO), or CD96 KO mice, but not DNAM-1 KO mice, were greater than after injection with parental B16/BL6 melanoma. NK cell depletion canceled the difference in the numbers of tumor colonies in WT mice. In vitro assays showed that sCD155 interfered with DNAM-1–mediated NK cell degranulation. In addition, DNAM-1 had greater affinity than TIGIT and CD96 for sCD155, suggesting that sCD155 bound preferentially to DNAM-1. Together, these results demonstrate that sCD155 inhibits DNAM-1–mediated cytotoxic activity of NK cells, thus promoting the lung colonization of B16/BL6 melanoma.
Spider Structure of Photoelectron Momentum Distributions of Ionized Electrons from Hydrogen Atoms for Extraction of Carrier Envelope Phase of Few-Cycle Pulses*
Authors: Tang Jiu , Zhang Guizhong , He Yufei , Li Meng , Ding Xin , Yao Jianquan
Published: February 2020

The spider structure in the photoelectron momentum distributions (PMDs) of ionized electrons from the hydrogen atom is simulated by solving the time-dependent Schrödinger equation (TDSE). We find that the spider structure exhibits sensitive dependence on carrier envelope phase (CEP) of the few-cycle pulses. To elucidate the striking CEP dependence of the spider structure, we select three physical parameters I
L, I
R, and I
R/I
L to quantitatively characterize the variations of the spider structure induced by altering the CEPs. I
L is the sum of the left half panel of the transverse cut curves (i.e., the sum of all the negative momenta along the laser polarization direction), I
R is the sum of the right half panel of the transverse cut curves (i.e., the sum of all the positive momenta along the laser polarization direction), and I
R/I
L is the ratio between the two sums. These parameters are shown to have monotonic relation with the CEP value, which is exploited to extract the CEPs. We anticipate that our method will be useful for obtaining CEPs encoded in the spider structure of PMDs.
Stable Compositions, Structures and Electronic Properties in K–Ga SystemsUnder Pressure*
Authors: Wang Chao , Liu Yun-Xian , Chen Xin , Lv Pin , Sun Hai-Rui , Liu Xiao-Bing
Published: February 2020

New stable stoichiometries in K–Ga systems are firstly investigated up to 100 GPa by the unbiased structure searching techniques. Six novel compositions as K4Ga, K3Ga, K2Ga, KGa, KGa2 and KGa4 are found to be thermodynamically stable under pressure. Most of the predicted stable phases exhibit metallic character, while the

F
d

3
¯

m

KGa phase behaves as a semiconductor with a bandgap ∼1.62 eV. Notably, the gallium atoms exhibit different interesting morphologies; e.g., Ga2 units, zigzag chains, six rings and cage. We further investigate the bonding nature of K–Ga systems with help of electron localization function and Bader charge analyses. Strong covalent bonding characteristics are found between the Ga and Ga atoms, and ionic bonding patterns are observed between the K and Ga atoms. Meanwhile, we notice charge transferring from the K atom to the Ga atom in the K–Ga systems. The present results can be helpful for understanding the diverse structures and properties of K–Ga binary compounds at high pressures.
Reduction of Electron Leakage of AlGaN-Based Deep Ultraviolet Laser Diodes Using an Inverse-Trapezoidal Electron Blocking Layer*
Authors: Xing Zhong-Qiu , Zhou Yong-Jie , Liu Yu-Huai , Wang Fang
Published: February 2020

To improve the optical and electrical properties of AlGaN-based deep ultraviolet lasers, an inverse-trapezoidal electron blocking layer is designed. Lasers with three different structural electron blocking layers of rectangular, trapezoidal and inverse-trapezoidal structures are established. The energy band, electron concentration, electron current density, P–I and V–I characteristics, and the photoelectric conversion efficiency of different structural devices are investigated by simulation. The results show that the optical and electrical properties of the inverse-trapezoidal electron blocking layer laser are better than those of rectangular and trapezoidal structures, owing to the effectively suppressed electron leakage.
Near-Field Optical Identification of Metallic and Semiconducting Single-Walled Carbon Nanotubes*
Authors: Wang Lele , Lyu Bosai , Gao Qiang , Chen Jiajun , Ying Zhe , Deng Aolin , Shi Zhiwen
Published: February 2020

Single-walled carbon nanotubes (SWCNTs), due to their outstanding electrical and optical properties, are expected to have extensive applications, such as in transparent conductive films and ultra-small field-effect transistors (FETs). However, those applications can only be best realized with pure metallic or pure semiconducting SWCNTs. Hence, identifying and separating metallic from semiconducting SWCNTs in as-grown samples are crucial. In addition, knowledge of the type of an SWCNT is also important for further exploring its new properties in fundamental science. Here we report employing scanning near-field optical microscopy (SNOM) as a direct and simple method to identify metallic and semiconducting SWCNTs on SiO
2
/Si substrates. Metallic and semiconducting SWCNTs show distinct near-field optical responses because the metallic tubes support plasmons whereas the semiconducting tubes do not. The reliability of this method is verified using FET testing and Rayleigh scattering spectroscopy. Our result demonstrates that the SNOM technique provides a reliable, simple, noninvasive and in situ method to distinguish between metallic and semiconducting SWCNTs.
Nucleation, Growth, and Aggregation of Au Nanocrystals on Liquid Surfaces*
Authors: Li Lu , Bao Zhi-Long , Ye Xun-Heng , Shen Jia-Wei , Yang Bo , Ye Gao-Xiang , Tao Xiang-Ming
Published: February 2020

We report the formation of gold ramified aggregates after deposition of Au on an ionic liquid surface by thermal evaporation method at room temperature. It is observed that the aggregates are composed of both granules and nanocrystals with hexagonal or triangular appearances. The most probable size of the nanocrystals is much larger than that of the granules and it increases with the nominal deposition thickness. The formation mechanism of the granules, nanocrystals and aggregates is presented.
Separability of symmetric states and vandermonde decomposition
Authors: Qian Lilong , Chen Lin , Chu Delin
Published: February 2020

Symmetry is one of the central mysteries of quantum mechanics and plays an essential role in multipartite entanglement. In this paper, we consider the separability problem of quantum states in the symmetric space. We establish the relation between the separability of multiqubit symmetric states and the decomposability of Hermitian positive semidefinite matrices. This relation allows us to exchange concepts and ideas between quantum entanglement and Vandermonde decomposition. As an application, we build a suite of tools to investigate the decomposability and show the power of this relation both in theoretical and numerical aspects. For theoretical results, we establish the witness for the decomposability similar to the entanglement witness and characterize the decomposability of some subclasses of matrices. Furthermore, we provide the necessary conditions for the decomposability. Besides, we suggest a numerical algorithm to check whether a given matrix is decomposable. The numerical examples are tested to show the effectiveness.
Waveform control of currents in graphene by chirped few-cycle lasers
Authors: Wu Erheng , Zhang Chaojin , Wang Zhanshan , Liu Chengpu
Published: February 2020

The residual current density in monolayer graphene driven by an intense few-cycle chirped laser pulse is investigated via numerical solution of the time-dependent Schrödinger equation in the light-field-driven regime. Strikingly, it is found that a purely chirped laser pulse breaks the inversion symmetry in graphene, generating a residual directional current, which is absent for a Fourier-transform limited pulse (2017 Nature
550 224) and is attributed to the chirp-dependent Landau–Zener–Stückelberg interference among different quantum pathways in the reciprocal space. Moreover, the directionality of such a current changes with laser chirp rate following a sine-functional way, which possibly provides a novel application in ultrafast photo-electronics based on two-dimensional materials.
First-principles investigation on ideal strength of B2 NiAl and NiTi alloys*
Authors: Zhang Chun-Yao , Tian Fu-Yang , Ni Xiao-Dong
Published: February 2020

For B2 NiAl and NiTi intermetallic compounds, the ideal stress–strain image is lack from the perspective of elastic constants. We use first-principles calculation to investigate the ideal strength and elastic behavior under the tensile and shear loads. The relation between the ideal strength and elastic constants is found. The uniaxial tension of NiAl and NiTi along

〈
001
〉

crystal direction leads to the change from tetragonal path to orthogonal path, which is driven by the vanishing of the shear constant C
66. The shear failure under {110}

〈
111
〉

shear deformation occurring in process of tension may result in a small ideal tensile strength (∼2 GPa) for NiTi. The unlikeness in the ideal strength of NiAl and NiTi alloys is discussed based on the charge density difference.
Lax pair and vector semi-rational nonautonomous rogue waves for a coupled time-dependent coefficient fourth-order nonlinear Schrödinger system in an inhomogeneous optical fiber*
Authors: Du Zhong , Tian Bo , Qu Qi-Xing , Zhao Xue-Hui
Published: February 2020

Optical fibers are seen in the optical sensing and optical fiber communication. Simultaneous propagation of optical pulses in an inhomogeneous optical fiber is described by a coupled time-dependent coefficient fourth-order nonlinear Schrödinger system, which is discussed in this paper. For such a system, we work out the Lax pair, Darboux transformation, and corresponding vector semi-rational nonautonomous rogue wave solutions. When the group velocity dispersion (GVD) and fourth-order dispersion (FOD) coefficients are the constants, we exhibit the first- and second-order vector semi-rational rogue waves which are composed of the four-petalled rogue waves and eye-shaped breathers. Both the width of the rogue wave along the time axis and temporal separation between the adjacent peaks of the breather decrease with the GVD coefficient or FOD coefficient. With the GVD and FOD coefficients as the linear, cosine, and exponential functions, we respectively present the first- and second-order periodic vector semi-rational rogue waves, first- and second-order asymmetry vector semi-rational rogue waves, and interactions between the eye-shaped breathers and the composite rogue waves.
Formation and magnetic properties of Ga–Pd–Tb 2/1 approximant
Authors: So Y G , Takagi K , Sato T J
Published: February 2020

The formation and magnetic properties of Tsai-type approximants in the Ga–Pd–Tb system were investigated. The 2/1 approximant with a lattice parameter of 2.313 nm formed in the Ga50.2Pd35.3Tb14.5 alloy annealed at 973 K for 100 h. The 2/1 approximant transformed into the corresponding 1/1 approximant through annealing at 1073 K in the alloy. For the 2/1 approximant, magnetic susceptibility measurements showed a sharp cusp at T
N ∼ 5.8 K, and both the field-cooled and zero-field-cooled susceptibilities coincided, indicating an antiferromagnetic transition at T
N. This is the first instance of long-range magnetic order in 2/1 approximants. On the other hand, spin-glass-like behavior was observed in the susceptibility for the 1/1 approximant, which may be attributed to the relatively large frustration of the icosahedral clusters in the 1/1 approximant.
Direct observation of the local atomic structure in two types of Au-Ge-Yb 1/1 approximants
Authors: Taguchi T , So Y G
Published: February 2020

The local atomic structure in two types of Tsai-type 1/1 quasicrystal approximants in the Au-Ge-Yb system were observed using scanning transmission electron microscopy (STEM). The high-angle annular dark-field (HAADF) imaging method in STEM was employed to detect the difference in local atomic structure at the cluster centers for both compounds. Two types of cluster centers were observed in the different compounds: a tetrahedron with various orientations and a single Yb atom. Furthermore, atomic-resolution energy-dispersive X-ray spectroscopy showed direct evidence for the presence of a single Yb atom at the cluster center for the later compound.
Diffraction of a model set with complex windows
Authors: Baake Michael , Grimm Uwe
Published: February 2020

The well-known plastic number substitution gives rise to a ternary inflation tiling of the real line whose inflation factor is the smallest Pisot-Vijayaraghavan number. The corresponding dynamical system has pure point spectrum, and the associated control point sets can be described as regular model sets whose windows in two-dimensional internal space are Rauzy fractals with a complicated structure. Here, we calculate the resulting pure point diffraction measure via a Fourier matrix cocycle, which admits a closed formula for the Fourier transform of the Rauzy fractals.
Description of Voronoi tiles in quasicrystals with octagonal symmetry
Authors: Ambrož Petr , Masáková Zuzana
Published: February 2020

We describe families of Voronoi tiles which appear in tilings of certain standard quasicrystal-like point sets with octagonal symmetry built using the cut-and-project construction.
Quasiperiodic tilings in hyperbolic space
Authors: Lück Reinhard
Published: February 2020

The standard methods to derive quasiperiodic patterns in Euclidean space were tested for hyperbolic space, which is represented by the Poincaré disc. A novel method to transform the icosahedral tiling of rhombohedra into the Poincaré disc is discussed.
Pentagonal quasicrystals and their linear self-similarities
Authors: Masáková Zuzana , Mazáč Jan
Published: February 2020

We recall the construction of a cut-and-project scheme providing planar model sets with 5-fold symmetry. The cut-and-project construction consists in projecting points of a lattice ℒ ⊂ ℝ4 by two orthogonal projections π
||, π
⊥ to two 2-dimensional subspaces. We describe the set of all linear mappings preserving the ℤ-modules π
||(ℒ) and π
⊥(ℒ) and show that the set of all such mappings is in a correspondence with a 2-dimensional cut-and-project set. Finally, we describe linear self-similarities of a pentagonal cut-and-project set with circular acceptance window.
Preparations and Properties of Nano-Structured AlxO/i-AlCuFe as Quasicrystalline Thermoelectric Composites
Authors: Huang J R , Takagiwa Y , Tsai A P
Published: February 2020

Nano-structured AlxO/i-AlCuFe quasicrystalline composites were synthesized using spark plasma sintering. In this study, the atomized i-AlCuFe powders (nominal with Al64Cu24Fe12) were calcined at 973 K for several hours to obtain the core-shell-like structure with AlxO and i-AlCuFe. AlxO layers grew from tens to a hundred of nanometers in thickness as the calcination duration increased. In other words, the Al content decreased within the i-AlCuFe owing to the formation of AlxO. The loss of Al dominated the electron transportation behavior, which triggered an N-type to P-type transition when the Al content was below 64 at%.
Analyzing by the Two-Level System and Conduction Mechanism of Icosahedral Quasicrystals CdYb and CdMgYb
Authors: Kanazawa I , Sekiyama Y , Maeda R , Nakajima M
Published: February 2020

We have presented one of possible mechanisms for anomalous transport properties in Tsai-type quasicrystals CdYb and CdMgYb. The tunneling process between the Tsai-type clusters has been argued in dilute bound approximation of dynamics of the two-level system.
Brownian motion and Edagawa phasons
Authors: Trebin Hans-Rainer , Lipp Hansjörg
Published: February 2020

The so far most direct observation of phasons was reported in the year 2000 by Edagawa et al. In HRTEM images of decagonal Al-Cu-Co they detected white spots which formed vertices of a quasiperiodic tiling. Some spots vanished and reappeared in phason flipped positions within seconds to minutes. Already at ICQ13 we had applied a structure model of Zeger and Trebin of the year 1996 to explain the physical origin of the spots and the time scale of the flips. We found that the spots are columns of ten-rings of atoms which change positions by fluctuations of atomistic phason flips. Thus they resemble Brownian motion of mesoscopic particles, which are pushed by fluctuating knocks of fluid molecules. Whereas Brownian motion is described by a random walk in continuous space, Edagawa phasons can be conceived as a random walk on a quasilattice.
C60 on impurity phases of the 2–fold surface of the Al–Pd–Mn quasicrystal
Authors: Coates Sam , Sharma Hem Raj , McGrath Ronan
Published: February 2020

Using STM, we show several off-stoichiometric impurity phases detected at the 2-fold Al–Pd–Mn quasicrystal surface. By comparing the observed surface structure to planes from similar bulk phases in the Al–Pd system, we identify these phases as β–Al–Pd and Pd5Mn3. C
60 is adsorbed at these domains, forming simple hexagonal close packed (hcp) structures. We identify potential adsorption schemes, and compare the adsorption behaviour to C60 on the quasicrystalline phase.
A Comparison between Si and SiC MOSFETs
Authors: Wang Jiawei
Published: February 2020

The Metal-Oxide-Semiconductor Field-Effect Transistor (MOSFET) has developed quickly and become one of the most important devices for a wide range of applications. There is an increasing need for power MOSFET devices with low power consumption and high energy efficiency. Silicon (Si) and Silicon Carbide (SiC) are two kinds of materials used in power MOSFET devices, which have their own advantages of performance for each use. This paper makes a comparison of the on-resistance and high-temperature performance between Si and SiC MOSFETs. The analysis of the differences between the two will mainly come out from the perspective of material properties, and the conclusion of what is the ideal material for power MOSFET devices will be finally drawn.
Distributed Energy Storage Optimization Configuration of Active Distribution Network
Authors: Zhe Jiang , Liang Wang , Xuxiang Huang , Xueshan Han , Dong Yang , Ning Zhou
Published: February 2020

With the high proportion of renewable energy access to the distribution network, the volatility and randomness of renewable energy output will have a serious impact on the distribution network, especially at the peak of renewable power output, the reverse trend phenomenon is obvious. The active distribution network displays the “power” characteristics externally, which makes the voltage problem and transmission congestion problem in the distribution network very serious. This paper establishes a distributed energy storage optimization configuration model that takes into account the voltage quality, and considers the energy storage operation strategy optimization in the energy storage site selection and volume model, which makes the energy storage configuration more reasonable, improves the voltage quality and enhances the renewable energy consumption capacity, improve the economics of system operation.
Antibacterial performance of Ag-doped TiO2/wood surface under visible light irradiation and its superior mould-resistance
Authors: Zhang Fu’an
Published: February 2020

The TiO2/wood (TW) based on fast-growing poplar wood was in situ synthesized through one-step solvothermal method and then Ag-doped TiO2/wood (ATW)was also prepared via the solvothermal method. The morphologies, crystal structure, and chemical characteristics of the composites were carried out by SEM, XRD, XPS and FTIR. The results of XPS and FTIR showed that the nanoparticles (TiO2 and Ag) were chemically bonded to the wood surface through the combination of hydrogen groups. Spherical-like Ag nanoparticles (Ag-NPs) was about 66 nm diameter. What’s more, the TW and ATW showed excellent antibacterial against Gram positive and negative bacterium under visible light irradiation and mould-resistance properties, which illustrated a significance and practical value in high added-value of wood.
Research on fire prevention and extinguishing technology in underhand working face of easy spontaneous combustion coal seam
Authors: Liu Xueli , You Jijun
Published: February 2020

The management of fire prevention and extinguishing in goaf becomes a major problem due to short spontaneous combustion period, poor roof caving conditions, large air leakage in goaf and difficulties for grouting. Oxygen consumption rate and the productivity of carbon monoxide are measured through the XK-VI spontaneous combustion test-bed, while prediction index gas for spontaneous combustion of the coal is obtained. Through the engineering practice test, the range of the gob “triple-zone” under the condition of nitrogen injection is acquired. Take 113101 working face of Bojianghaizi coal mine as an example. The method for detecting the fire prevention effect is to inject nitrogen into the goaf, supplemented by measures such as forced anchoring in the intake and return wind lane, constructed of the sandbags separation wall, and embedded the beam tube through the goaf. The volume fraction of carbon monoxide in the return corner and the R2 value are used as predictors of fire prevention. Engineering practice test shows that there is no danger of spontaneous combustion in the working face when the volume fraction of carbon monoxide in the return corner is less than 200*10−6 and the value of R2 is less than 0.2. The process has reference significance for the fire prevention management of the Bojianghaizi Mine and other similar conditions.
Research on High Efficiency IO Control Technology of Seismic Data Based on Data Segmentation
Authors: Liu Liting , Zhang Xi , Chen Yu
Published: February 2020

With the development of geophysical prospecting technology, seismic operation processing is terabytes of data in actual production. A seismic operation processing time can be as long as ten days. In order to complete these processing tasks in as short a time as possible, efficient use of node resources is needed. Therefore, it is necessary to segment and decouple the input data in order to improve the computational efficiency when carrying out such large amount of data, intensive calculation and long running time operations. IO control system can decompose such jobs into several sub-jobs for parallel processing, so as to shorten the running time, improve the efficiency of seismic data processing and enhance the computing performance of cluster system.
Study on Optimization Application of Iron Ion Stabilizer in the Polymer Injection Process of Offshore Oilfield
Authors: Zhu Shanshan , Zhu Shijie , Zhang Hong , Liu Changlong , Shi Leiting , Ye Zhongbin
Published: February 2020

A large amount of Fe2+/Fe3+ ions are produced by corrosion and fouling in the high-pressure polymer injection process of offshore platforms, which will affect the viscosity of the polymer solution, and is difficult to effectively control by the addition of stabilizers in the curing tank. In order to solve this problem, this paper has carried out related research and the results show that: 1) Fe2+ mainly generates free radicals (·OH) by oxidation catalysis, to destroy long chains of polymer molecules, causing irreversible fragment breakage, resulting in a significant decrease in polymer viscosity; 2) Fe3+ mainly binds to hydroxyl groups, resulting in flocculation and viscosity reduction of polymers; 3) Stabilizers with complexation can effectively control Fe3+ to form water-soluble complexes, while excess stabilizers increase salt content and reduce polymer viscosity by electrostatic shielding effect. In order to effectively control the influence of Fe2+/Fe3+ and the stabilizer on the polymer solution in the production process, an appropriate amount of complex stabilizer should be added to the diluent inlet of the mixture of the polymer mother liquor and the diluent.
Laboratory Study on Active Aging Oil Plugging Agent
Authors: Liu Shasha , Zhang Yanru , Yan Haijun , Xie Gang , Lu Cheng , Jing Jizhe , Wei Aijun , Qin Zhonghai , Shi Lei
Published: February 2020

Aging oil refers to the stable emulsion of crude oil formed by emulsification that cannot be treated by conventional surfactants due to the influence of bacteria, chemical agents, self asphaltene and colloid in the process of crude oil exploitation, transportation and processing. There is a large amount of aging oil stored in the joint station of the production plant in Huabei oilfield, which not only causes certain harm to the gathering and transportation system, but also brings heavy environmental burden to the oilfield. In this study, on the basis of physical property analysis of aging oil samples, the properties of aging oil and emulsifying resin plugging agent were compared. And the water plugging principle of emulsion resin was used for reference. The system of active aging oil plugging agent is constructed by experiment. Core displacement experimental evaluation shows that active aging oil core water plugging rate was 98%, the breakthrough pressure gradient was 26 MPa.m−1, and it has good plugging effect.
Study on Yield Mechanical Properties of High Availability Materials before and after Aging for Intelligent Measurement Equipment
Authors: Zheng Angang , Yuan Xiangyu , Wang Yifan , Shang Huaiying , Liu Yan , Zhang Wulei
Published: February 2020

One of the key technical research points in the field of smart grid measurement is to make a breakthrough in the detection and evaluation of high availability materials in intelligent measurement equipment. The comprehensive cross-action of multi-environmental stress brings a lot of data, how to find the key parameters in it, and how to analyze the complex environment into the characteristic combination of multiple single environmental factors, and the mathematical model of nonlinear evolution and service life of material aging based on the characteristic expression of the combination, all of the above are the key points and difficulties of the research. On the basis of the service life model, the research on differential protection measures and the study of life evaluation technology for smart grid measurement equipment can enable the equipment to realize wide-area application and high availability under more harsh conditions, which is one of the key points to improve the quality control in NQI system.
Application of Point-by-Point Vector Synthesis in Walkaway VSP Logging Data Processing
Authors: Liu Fei , Qin Li , Tang Jian , Cheng Lili
Published: February 2020

At present, it is necessary to use Walkaway VSP logging imaging data to drill horizontal shale gas wells in exploration areas lacking three-dimensional seismic data. Walkaway VSP logging imaging profile can delineate the formation structure around wells, obtain detailed information of dip, inclination and fault around wells, and guide the trajectory design of horizontal wells. But VSP logging is richer and more complex than conventional seismic data. The precondition of up-going wave imaging is to separate up-going P-wave or converted S-wave from complex wave field. Nowadays, most vector synthesis techniques can not completely separate up-going P-wave from up-going converted wave, which affects the accuracy of final imaging results. In order to achieve the best wave field separation effect of VSP logging data, the point-by-point vector synthesis technique is adopted. Firstly, the directional rotation synthesis of horizontal components is carried out according to the maximum energy criterion. Then the rotational synthesis of horizontal and vertical components uses ray tracing based on velocity model to estimate the polarization angle of time-varying upward reflected P-wave or converted wave. The method of “velocity fine-tuning scanning” is applied to search for the best synthesis angle, and the point-by-point vector synthesis is carried out by calculating the time-varying polarization angle. Finally, the best separation effect data are selected as the final vector synthesis result. This technique solves the problem that conventional vector synthesis cannot completely separate up-going P-wave from up-going converted S-wave. Upward P-waves acquired after separation has clear characteristics, more continuous phase axis and good fidelity processing effect, which lays a solid foundation for fine imaging of target formation in the study area and has become an indispensable key supporting technology for optimizing the trajectory of horizontal wells in shale gas development in Sichuan Basin.
Thermal Properties of Poly(L-lactide) Containing Succinic Dihydrazide Derivative
Authors: Zhao Lisha , Cai Yanhua
Published: February 2020

The slow crystallization speed is one of the most important factors restricting the development of Poly(L-lactide) (PLLA). In this paper, a succinic dihydrazide derivative BPASD was prepared to study its influence on the PLLA’s non-isothermal crystallization behavior and thermal decomposition behavior. A comparative study on the melt-crystallization of the PLLA/BPASD and pure PLLA showed that the BPASD could promote the melt-crystallization of PLLA in cooling, and a larger amount of BPASD exhibited the better nucleation effect for PLLA. However, the cold-crystallization peak moved to the lower temperature with increasing of BPASD loading. Additionally, the cooling rate and the heating rate were two improtant factors to the crystallization process of PLLA. Thermal stability measurements showed that the pure PLLA and all PLLA/BPASD samples have only one thermal decomposition profile, but the presence of BPASD reduced the thermal stability of PLLA.
Evaluation and Optimization of Corrosion Inhibitor System
Authors: Yun Liu , Qingzhen Du , Wei Xiong , Yanfang Gao , Fang Shang , Wei Zhang , Gangliang Li
Published: February 2020

By combining two methods of weightlessness and electrochemistry, the corrosion inhibitors have been selected and optimized. The orthogonal experiment has been carried out to optimize the inhibitor’s performance. The range analysis results indicated that corrosion inhibition performance of optimized corrosion inhibitor (HZ-1) has been improved remarkably. The corrosion inhibition rate can reach 94.66% with lower corrosion current density. The optimum concentration of HZ-1 is 90 mg/L and working temperature is 80∼100°C. Its site application shows that the inhibitor also has remarkable corrosion inhibition effect, the concentration of iron ions is decreases, and the period of pumping wells has been prolonged significantly.
Study on Electromagnetic Wave Absorption performance of Dendritic-like Co
Authors: Yang Fuli , Hou Xingzhe , Wang Lirui , Li Youjiang , Zhang Xuecong , Yu Miao
Published: February 2020

Dendritic-like Co particles consisting of leaf-shaped nano-units were successfully synthesized by chemical reduction method. The absorbing particles have abundant multi-stage branches. Since the crystal structure, size and special morphology have an important influence on the microwave absorption performance, the X-ray diffractometer, scanning electron microscope, vibration sample magnetic measurement and vector network analysis are used to characterize the dendritic Co. Absorbing mechanism was analyzed systematically. The nano-sized, multi-stage branches, porous structures and rough surfaces of the prepared particles all contribute to the penetration, scattering and attenuation of EM waves. Hence the composite, in the test band, especially in the S-band (2-4 GHz), presents excellent microwave absorption properties.