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For the timely transmission of signals, the research of low dielectric constant microwave ceramics is essential. In this study, a new type of low-permittivity Lu2MgAl4SiO12 microwave dielectric ceramic was prepared by traditional solid-phase method. The successful synthesis of Lu2MgAl4SiO12 ceramics with cubic crystal system and space group Ia-3d (230) was determined by XRD and Rietveld refinement. SEM observation confirmed the garnet structure of Lu2MgAl4SiO12 ceramics, and verified the dense structure of the ceramic samples with a relative density of 99.1%. In addition, the influence of relative density and packing fraction on Q × f was studied by analyzing the Lu2MgAl4SiO12 system. The findings revealed that τf was affected by the valence state of VSi-O bond. Finally, Lu2MgAl4SiO12 sample sintered at 1490 °C demonstrated notable microwave properties (εr = 9.13, Q × f = 15,100 GHz, τf = –47.1 ppm/°C). [ABSTRACT FROM AUTHOR]

For the timely transmission of signals, the research of low dielectric constant microwave ceramics is essential. In this study, a new type of low-permittivity Lu2MgAl4SiO12 microwave dielectric ceramic was prepared by traditional solid-phase method. The successful synthesis of Lu2MgAl4SiO12 ceramics with cubic crystal system and space group Ia-3d (230) was determined by XRD and Rietveld refinement. SEM observation confirmed the garnet structure of Lu2MgAl4SiO12 ceramics, and verified the dense structure of the ceramic samples with a relative density of 99.1%. In addition, the influence of relative density and packing fraction on Q × f was studied by analyzing the Lu2MgAl4SiO12 system. The findings revealed that τf was affected by the valence state of VSi-O bond. Finally, Lu2MgAl4SiO12 sample sintered at 1490 °C demonstrated notable microwave properties (εr = 9.13, Q × f = 15,100 GHz, τf = –47.1 ppm/°C). [ABSTRACT FROM AUTHOR]

This study delves into the microwave dielectric properties of SrLaMgTaO6 ceramics synthesized via traditional solid-state methods. Precise lattice parameters observed at the optimal temperature were as follows: a = b = c = 7.97327 Å, with a corresponding unit volume of V = 506.884775 Å3. Utilizing X-ray diffraction (XRD) patterns and detailed Rietveld refinement analysis at various temperatures revealed that SrLaMgTaO6 ceramics possess a cubic structure, specifically within the Fm-3 m (225) space group. The structure of ceramic particles was further studied by scanning electron microscopy (SEM), and it was found that the optimum relative density was 95.7%. Additionally, within SrLaMgTaO6 ceramic samples, the study explored the relationship between relative density, porosity, filler fraction, and microwave performance. A significant finding was the impact of the Ta–O bond valence (VTa–O) on the frequency temperature coefficient. At 1480 °C, SrLaMgTaO6 ceramics demonstrated superior performance metrics: a dielectric constant (εr) of 21.68, a quality factor (Q × f) of 16,739 GHz (f = 8.74 GHz), and a frequency temperature coefficient (τf) of -79.1 ppm/°C. The findings highlight the material’s potential as a robust dielectric in microwave applications. [ABSTRACT FROM AUTHOR]

Electrocatalytic water splitting has been identified as a potential candidate for producing clean hydrogen energy with zero carbon emission. However, the sluggish kinetics of oxygen evolution reaction on the anode side of the water‐splitting device significantly hinders its practical applications. Generally, the efficiency of oxygen evolution processes depends greatly on the availability of cost‐effective catalysts with high activity and selectivity. In recent years, extensive theoretical and experimental studies have demonstrated that cobalt (Co)‐based nanomaterials, especially low‐dimensional Co‐based nanomaterials with a huge specific surface area and abundant unsaturated active sites, have emerged as versatile electrocatalysts for oxygen evolution reactions, and thus, great progress has been made in the rational design and synthesis of Co‐based nanomaterials for electrocatalytic oxygen evolution reactions. Considering the remarkable progress in this area, in this timely review, we highlight the most recent developments in Co‐based nanomaterials relating to their dimensional control, defect regulation (conductivity), electronic structure regulation, and so forth. Furthermore, a brief conclusion about recent progress achieved in oxygen evolution on Co‐based nanomaterials, as well as an outlook on future research challenges, is given. [ABSTRACT FROM AUTHOR]

This investigation explores the microwave dielectric characteristics of BaCa13Mg2(SiO4)8 ceramics, synthesized through conventional solid-state techniques. Via X-ray diffraction analysis and comprehensive data refinement across various temperatures, we unequivocally determined the orthorhombic crystal structure of the BaCa13Mg2(SiO4)8 ceramics. The measured lattice parameters at a sintering temperature of 1345 °C are a = 18.51543 Å, b = 6.77482 Å, and c = 10.95537 Å, with a corresponding unit volume of V = 1374.226706 Å3. The microstructure of the ceramic grains was studied in detail by scanning electron microscopy (SEM), and it was found that the optimum relative density was 97.2%. The study further explored the effects of porosity, packing fraction, relative density, and the impact of Si–O bond valence (VSi-O) on the microwave dielectric characteristics of BaCa13Mg2(SiO4)8 ceramics. Remarkably, the BaCa13Mg2(SiO4)8 ceramics exhibited exceptional performance metrics (εr = 11.53, Q × f = 15,231 GHz (f = 10.6 GHz), τf = − 27.3 ppm/°C) at 1345 °C, establishing it as a promising candidate for microwave applications. [ABSTRACT FROM AUTHOR]

In this work, a silicate ceramic, CaY2Al4SiO12 (CYASO), with a low dielectric constant and low loss was prepared using traditional solid-state methods. X-ray diffraction (XRD) refinement analysis shows that the CYASO material crystallized into a phase with an Ia-3d space group and an impurity peak. The orthogonal cubic structure of the CYASO ceramic was confirmed through transmission electron microscopy (TEM), and the structure exhibited an orderly layered arrangement. The internal microstructure was characterized using scanning electron microscopy (SEM), which showed that the sample's relative density reached 97.8%. We discuss the correlation between the full width at half maximum (FWHM) of the Raman matrix corresponding to the vibration mode of the symmetric bending mode of AlO4 at the Raman shift of 855 cm−1 and the Q × f value. Additionally, the analysis focused on the various factors that influence the dielectric constant, including density, secondary phase, and porosity changes. The ceramics exhibited remarkable microwave dielectric properties (εr = 8.7, Q × f = 34,700 GHz, τf = −35 ppm/°C) when calcined at 1425°C. CYASO ceramic shows great capacity as a microwave dielectric material. [ABSTRACT FROM AUTHOR]

The discovery of overcounting in Orkhon Inscriptions has been an important contribution by historical comparative linguistics during the nineteenth century. However, the initial interpretation of overcounted numerals in Orkhon Inscriptions by Thomsen and Radloff was not correct, resulting in serious difficulties in reconstructing old Turkic history. It was Bang and Marquart who worked out the true semantics of overcounted numerals. This article aims to present a historical overview on the discovery and interpretation of overcounted numerals in Orkhon Inscriptions. Considering that Bang and Marquart did not explicitly spell out their evidence for reaching the true semantics of these numerals, this article presents a series of arguments proving the existence of overcounting in Old Turkic based on language per se, historical facts, logical reasoning, and bilingual translation. [ABSTRACT FROM AUTHOR]

This article focuses on the controversy over whether complex numerals in English are constituents. Contra the traditional view (e.g. Hurford 1975; Greenberg 1990 [1978]), the cascading structure proposed in Ionin & Matushansky (2006, 2018) maintains that cross-linguistically a complex numeral does not form a constituent to the exclusion of the NP complement. The derivation of an additive complex numeral, e.g. twenty-two people , thus involves an underlying source form with a nominal conjunction, e.g. twenty people and two people. Based on the argumentation established in He (2015) and He et al. (2017) supporting complex numerals as constituents in Chinese and minority languages in southern China, this article first demonstrates that the non-constituency analysis is not viable for English, as the underlying forms of additive complex numerals may be ill-formed and also not semantically equivalent to the surface forms. We then offer evidence to support the constituency analysis from constituency tests and behavior of post-numeral and pre-numeral modifiers. Finally, we demonstrate that the extra mechanism of grafting, proposed by Meinunger (2015), is unnecessary for English complex numerals. [ABSTRACT FROM AUTHOR]

To obtain dual active near-infrared (NIR) nanomaterial with strong absorption and emission properties, we report herein a novel precursor reactivity differentiation strategy, i.e., utilizing 1-octadecene (ODE)-Se having the ability to react with Ag salts much stronger and faster than ODE-thiourea, for single-step preparation of Ag2Se@Ag2S nanocrystals (NCs). With this strategy, we were able to synthesize high-quality Ag2Se@Ag2S NCs with both excellent NIR absorption and emission properties. Particularly, these nanocrystals possess a rather strong and sharp excitonic absorption peak with a full width at half maximum less than 70 nm and a maximum fluorescence quantum yield as high as 24.3%. Their appealing optical properties and structural features were founded to be highly dependent on the Se to S precursor ratio in the reaction solutions, owing to such a ratio exerting a direct influence on the core sizes and shell thicknesses of the as-formed NCs. Taking advantage of their remarkable NIR absorption properties, self-powered photoelectrochemical-type photodetectors based on the as-prepared Ag2Se@Ag2S NCs were successfully fabricated, which demonstrate a much better response performance and photostability in comparison with those based on Ag2Se NCs. [ABSTRACT FROM AUTHOR]

This paper explores a typology of overt coordination in additive numerals in a number of minority languages in South China. Among approximately 100 minority languages surveyed, 26 languages feature different coordinators for additive numerals and noun phrases. We show that these two types of coordinators are not semantically, etymologically, or morphologically related. This phenomenon presents a serious challenge to the proposal that additive numerals do not form constituents and that numeral coordination is derived from underlying nominal coordination in such languages. [ABSTRACT FROM AUTHOR]

In this essay, we propose that Peirce's Existential Graphs can derive the desired uniqueness implication (or in a weaker claim, the definite description readings) of donkey pronouns in conjunctive discourse ( A man walks in the park. He whistles), without postulating a separate category of E-type pronouns. [ABSTRACT FROM AUTHOR]

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Focuses on translating brand names from Chinese to English. Importance of names to businesses; Four approaches in the Chinese way of translation of brand names; Reason the literal translation method is better than the Pinyin approach; Advantages of the transliteration method; Characteristics of a translators; Criteria for assessing a translated brand name.