Terahertz dielectric properties of plasma-sprayed thermal-barrier coatings

We investigated the electromagnetic wave transmittance and dielectric properties of yttria partially stabilised zirconia thermal-barrier coatings by terahertz time-domain spectroscopy in which the samples were irradiated by a pulsed THz wave in the frequency range of 0.1-6.3 THz. The coating microstructure was varied by changing the spray conditions and the THz transmittance and dielectric constants were examined as functions of frequency. The coatings exhibited a high transmittance of 20%-80% at frequencies below 0.5 THz and almost zero transmittance above 1.5 THz. The refractive index n for different coatings ranges from 4 to 6, depending on the coating microstructure. For any given coating, n increases to some extent with increasing frequency. Unlike the imaginary part of the dielectric constant, the real part of the dielectric constant is strongly correlated with the porosity of the coatings, which suggests that terahertz spectroscopy may potentially be used to non-destructively evaluate the porosity of ceramic coatings.     

On an Inequality That Implies the Lower Bound Formula for the Probability of Correct Selection in the Levin-Robbins-Leu Family of Sequential Binomial Subset Selection Procedures

Abstract

We study a key inequality that implies the lower bound formula for the probability of correct selection and other selection-related events of interest in the Levin-Robbins-Leu family of sequential binomial subset selection procedures. We present a strategy for the proof of the key inequality, and a mostly complete general proof is given. The strategy provides an entirely complete and rigorous proof of the inequality for as many as seven competing populations using computer-assisted symbolic manipulation.     

Rheological and thermal properties of an enteral nutrition formula for nutritional support patients using a combined mixture of gelatin and maltodextrin

Enteral nutrition is a type of nutritional support that provides the necessary sources of energy and protein for patients who suffer from dysphagia, chronic disease, and loss of appetite. In this study, a gelatin-maltodextrin binary biopolymer system has been incorporated into a semi-solid formula. The I-optimal combination design approach was used to create 19 formulations, and the dynamic rheological properties, dynamic laser scattering, and zeta potential responses were evaluated over 30 days of storage at 5°C. Solid viscoelastic behavior has been approved since G′ > G″ in the frequency sweep test with no cross-over point. Maltodextrin may interfere within the gelatin network, and increasing the maltodextrin to gelatin (from 0.14 to 1) may lead to a wider linear viscoelastic (LVE) strain range (2.16%), a lower storage modulus at LVE (52%), a lower yield stress (46%), and a lower glass transition temperature (34%). The presence of maltodextrin may reduce the temperature of the sol-to-solid transformation by 48% and enhance its flexibility. In contrast, increasing the gelatin-to-maltodextrin ratio following melting at 37°C led to an increase in the cumulant mean and polydispersity index, indicating a relatively unstable system. The range of zeta potential values between −4.4 and 1.7 mV confirmed a tendency toward coagulation. Microscopic images revealed instability because of irregular or compact chains formed in the gelatin matrix by using higher amounts of maltodextrin. Finally, the best formula had the best rheological stability and was suitable for tube-feeding patients, with a gelatin-to-maltodextrin ratio of 4.35:3.64% w/w on day 17.4.     

Investigation of 14–15 MeV (<Emphasis Type="Italic">n,t</Emphasis>) Reaction Cross-sections by Using New Evaluated Empirical and Semi-empirical Systematic Formulas

In the hybrid reactor, tritium self-sufficiency must be maintained for a commercial power plant. For self-sustaining (D-T) fusion driver tritium breeding ratio should be greater than 1.05. Working out the systematics of (n, t) reaction cross-sections are of great importance for the definition of the excitation function character for the given reaction taking place on various nuclei at energies up to 20 MeV. In this study we have investigated asymmetry term effect for the (n, t) reaction cross-sections at 14–15 neutron incident energy. It has been discussed the odd–even effect and the pairing effect considering binding energy systematic of the nuclear shell model for the new experimental data and new cross-sections formulas (n, t) reactions developed by Tel et al. We have determined a different parameter groups by the classification of nuclei into even–even, even–odd and odd–even for (n, t) reactions cross-sections. The obtained empirical and semi-empirical formulas by fitting two parameter for (n, t) reactions were given. All calculated results have been compared with the experimental data and the other semi-empirical formulas.     

不可满足公式的同态证明系统

合取范式(CNF)公式H到F的同态φ是一个从H的文字集合到F的文字集合的映射,并保持补运算和子句映到子句.同态映射保持一个公式的不可满足性.一个公式是极小不可满足的是指该公式本身不可满足,而且从中删去任意一个子句后得到的公式可满足.MU(1)是子句数与变元数的差等于1的极小不可满足公式类.一个三元组(H,φ,F)称为的一个来自H的同态证明,如果φ是一个从H到F的同态.利用基础矩阵的方法证明了:一个不可满足公式F的树消解证明,可以在多项式时间内转换成一个来自MU(1)中公式的同态证明.从而,由MU(1)中的公式构成的同态证明系统是完备的,并且由MU(1)中的公式构成的同态证明系统与树消解证明系统之间是多项式等价的.     

母乳中长链甘油三酯研究进展

母乳中甘油三酯的结构对于婴幼儿的脂肪消化吸收具有重要影响。作者所在团队前期研究结果显示,母乳脂肪天然富含中长链甘油三酯（MLCT）,是母乳中含量最丰富的一类甘油三酯,其质量约占总甘油三酯的30%,主要结构是一个中链脂肪酸和两个长链脂肪酸构成的单中链型甘油三酯（MLL）。母乳中几乎不含中链甘油三酯（MCT）。作者综述了母乳脂肪中MLCT的含量、组成、影响因素以及母乳与婴幼儿配方奶粉中甘油三酯的差异,总结了MLCT的消化特性,以及MLCT型母乳替代脂的研究进展,为新型配方奶粉脂肪的开发提供理论依据。     

Omnidirectional autonomous entry guidance based on 3-D analytical glide formulas

An autonomous entry guidance law is developed based on 3-D analytical glide formulas, where the downrange formula is used to plan the longitudinal reference profile in order to meet the downrange and final energy requirements, and the crossrange formula is used to regulate the bank reversals in order to eliminate the crossrange error. As the analytical glide formulas ignore the effects of the Earth׳s rotation, a series of strategies is proposed for compensating these effects, which provides the guidance with the capability of steering the hypersonic glide vehicle with high Lift to Drag ratio (L/D) to any place of the world accurately. The compensation strategies can be summarized into two parts: (1) the reference profiles are properly adjusted by roughly evaluating the effects of the Earth׳s rotation on the aerodynamic profiles over the whole flight, which can compensate most of the effects; (2) the current effects are accurately evaluated and then the guidance commands are slightly modulated for compensating the remaining effects. Due to careful design, the strategies will not result in drastic changes in the Angle of Attack (AOA) and can keep the bank angle almost constant during most of flight.     

Characterization and suitability of polyphenols-based formulas to replace sulfur dioxide for storage of sparkling white wine

The sparkling wine protection against air is of interest for maintaining its sensorial profile and it is achieved through the use of antioxidants while disgorging. Sulfur dioxide (SO₂) is commonly added, but its amount should be limited due to human health problems. The suitability of three polyphenols-based commercial formulas containing plant gallic and ellagic acids extracted from grape (Vitis vinifera L.) (AO1), plant ellagic acid and gum arabic (AO2), and plant gallic, ellagic acids and Saccharomyces cerevisiae cell-wall fractions (AO3) was evaluated after 7 months storage (at 15 °C and 25 °C) of disgorged sparkling white wine. The phenolic composition of these formulas was investigated through spectrophotometric measurements. Moreover, the phenols were characterized and quantified by HPLC-MS analyses. The sotolon concentration and the absorbance values at 420 nm were determined in wines. The HPLC-MS analysis showed that the formula AO1 mainly contained gallotannins, ellagic tannins and flavan-3-ols, while AO2 had high levels of flavan-3-ols and gallotannins. Flavan-3-ols were the only phenols found in AO3. The addition of these formulas increased the yellow hue. Sotolon was higher than the perception threshold in the samples with AO2 and at trace amount in the samples with both AO1 and AO3 only stored at 25 °C. The tested antioxidant formulas seemed to be less effective of SO₂ for the storage of sparkling white wine. However, the investigation of phenolics in antioxidant formulas could be helpful for the proper choice of a potential substitute of SO₂ due to increase interest in sulfur-free wine production.     

Handling inheritance in a system integrating logic in objects

The inheritance mechanism of SILO, a system integrating a many-sorted logic within an object-based framework, is presented. In order to be adequate for knowledge representation, it comprises two components, a hardwired and a user-definable. Due to use of typed (sorted) terms, a variety of specialisation types between logical formulas (axioms) are introduced and defined. Thus, the hardwired component is able to represent a variety of inheritance/specialisation relations between objects. The notion of a conflict is defined and conflict detection theorems are introduced. Also, consequence retraction is introduced and used alongside attribute/predicate overriding to resolve conflicts. The user-definable component consists of a number of user definable functions, called meta-functions, which are able to implement both global and local inheritance control. It is based on a partial reflection meta-level architecture.     

二元混合气体通过金属微孔膜扩散分离的计算和实验

本文讨论了二元混合气体通过微孔金属膜扩散分离的过程。给出通用的膜后气体浓度计算公式。这些公式建立在毛细管模型和微孔膜模型之上。已证明，适用于计算同位素气体膜后浓度的公式不过是本文所给公式的一些特例。用Ｈ２－Ｎ２二元混合气体通过微孔金属膜进行了扩散分离实验。实验结果与计算值符合很好。原则上，本文所给公式也适用于计算微孔陶瓷膜膜后气体浓度。