Diffusion Bonding of FGH 98 and CoCrNi-Based Medium-Entropy Alloy: Microstructure Evolution and Mechanical Tests

The superalloy FGH98 was successfully diffusion bonded (DB) with medium-entropy alloy (MEA) Al3Ti3(CrCoNi)94 using pure Ni as the interlayer at a temperature range of 1050–1170 °C for 1 h under 5 MPa. The microstructure and mechanical properties of joints were investigated. The diffusion bonding seam was composed of an interlayer zone (IZ) and two diffusion-affected zones (DAZ). The IZ and DAZ beside the FGH98 consisted of cubic Ni3(TiAl)-type γ′ phases due to the diffusion of Ti and Al atoms. Meanwhile, the DAZ adjacent to the MEA consisted of spherical γ′ phases. Both of the γ′ phases with different morphology kept the coherent relationship with the matrix. Moreover, increase of bonding temperature led to the morphology of interlayer γ′ phase to transform from sphere to cube. Due to the strengthening effect of a mass of γ′ phase distributed evenly in IZ and the DAZ beside the FGH98, the microhardness and Young’s modulus of these two zones were higher than that of DAZ near the MEA. The maximum shear strength of DB joint, 592 MPa, was achieved in the joint bonded by 1150 °C, which was the typical ductile fracture feature confirmed by the shear dimples.

THE ROLE OF THAI PEOPLE IN VIETNAM – LAO TRADITIONAL FRIENDSHIP

Vietnam - Laos has more than 2,000 km of common national borders. The coherent relationship between the two nations and the inhabitants of the two countries has been formed and fostered in history and especially developed over the past 7 decades. The Thai ethnic group in Vietnam has over one million people, residing permanently, concentrated in the Northwest region, the region consists of 8 provinces, of which 4 provinces have the Vietnam-Laos border crossing. This paper focuses on clarifying the practical basis for the Thai people to play a role in the traditional Vietnam-Laos friendship and propose some solutions to promote the role of Thai in maintaining, developing the traditional friendship between Vietnam and Laos, now and in the future.

Investigation of NbC/TiC Heterogeneous Nucleation Interface by First-Principles and Experimental Methods

The mechanism of the heterogeneous nucleation of NbC on TiC precipitates was investigated systematically in this paper. The interfacial properties of NbC (100)/TiC (100), NbC (110)/TiC (110), and NbC (111)/TiC (111) interfaces were studied by first-principles calculations. The results showed that the NbC (111)/TiC (111) interface with the Nb–C bond is the most stable one, and the stability of interfaces with the C–Ti, Nb–Ti, and C–C bonds decreases in turn. The interface of the Nb/C-terminated and Third Layer (TL) stacking sequence (NCTL) has the largest adhesion work (10.15 J/m2) and the smallest equilibrium interface spacing (1.290 Å). In the range of low niobium (Nb) chemical potential and high carbon (C) chemical potential, the nucleation of NbC on TiC precipitates takes precedence over the epitaxy growth in the coherent relationship of [ 1 1 ¯ 0 ] ( 111 ) NbC / / [ 1 1 ¯ 0 ] ( 111 ) TiC , while the nucleation of NbC on TiC precipitates is prior to the epitaxy growth in the coherent relationship of [ 001 ] ( 100 ) NbC / / [ 001 ] ( 100 ) TiC in the range of high niobium (Nb) chemical potential and low carbon (C) chemical potential. Besides, the characteristics of heterogeneous nucleation precipitates in Nb–Ti microalloyed steels were analyzed by transmission electron microscopy (TEM). The orientation relationship between the (Ti, Nb) C and (Nb, Ti) C precipitates follows [ 1 1 ¯ 0 ] ( 111 ) ( Nb , TiC ) / / [ 1 1 ¯ 0 ] ( 111 ) ( Ti , Nb ) C , which is consistent with the calculated result.

Kinetic Analysis for High-Temperature Coarsening of γ″ Phase in Ni-Based Superalloy GH4169

The growth of precipitates in Ni-based superalloy GH4169 is critical as it controls the mechanical properties and long-term stability of the alloy. In this paper, the coarsening behavior of the main strengthening phase γ″ in the temperature range from 800 °C to 900 °C is investigated. Two heat treatment steps, i.e., pre-precipitation of γ″ phase and coarsening of precipitates at high temperatures, were performed on the GH4169 alloy. It was found that there were three morphological forms of γ″ phase in chronological order: lip-shape, disc-shape, and irregular rectangle-shape with larger size. The coarsening kinetics of γ″ phase followed the Lifshitz-Slyozov-Wagner (LSW) time-law for diffusion-controlled growth, and the activation energies of γ″ phase before and after losing the coherent relationship with matrix were 261 kJ mol−1 and 271 kJ mol−1, respectively.

Opportunity and Willingness: From “Ordering Concepts” to an Analytical Perspective for the Study of Politics

The opportunity/willingness framework (O/W) is presented as an agent-structure approach to the understanding of international relations (IR) and international conflict, with deep roots in the “ecological triad” of Harold and Margaret Sprout. While originally developed to organize thinking about international politics, this article describes how it has evolved into a guide for generating IR theory, developing research designs to study IR, and ways to evaluate those theories. It does this by showing how to synthesize what we know and bring together apparently disparate hypotheses and evidence to bear—crossing a variety of analytic boundaries—and by pulling together what we know across levels of analysis, academic disciplines, and the sub-disciplines of political science. O/W compels scholars to cross, link, and synthesize levels of analysis—complementing theories built around levels of analysis, while at the same time moving them forward in order to deal with the complex causation they have to confront. This complex causation derives from the logical features of O/W, which regards opportunity and willingness as jointly necessary conditions for the occurrence of any event. A discussion of the characteristics of necessity and sufficiency as causal processes leads to the conclusion that not only does this joint necessity distinguish O/W from theoretical approaches that are deterministic, monocausal, or are concerned only with either opportunity or willingness, but is the beginning of a logical story that demonstrates how this framework can deal with causal complexity. The joint necessity of opportunity and willingness, along with its two corollaries of “substitutability” and “nice laws,” forces a researcher to more fully specify the logical and substantive structure of the theoretical statements under investigation, and to ensure the research design is relevant to the theory and set of research hypotheses—such that there is a coherent relationship among the components of logic, theory, and method. At the end of the logical story developed in the article, it can be seen that O/W has moved well beyond an organizing principle and is a model of causal complexity of great potential.

Is there a correlation between physicians' clinical impressions and patients' perceptions of change? Use of the Perceived Change Scale with inpatients with mental disorders

Introduction: Assessment of the results of treatment for mental disorders becomes more complete when the patient's perspective is incorporated. Here, we aimed to evaluate the psychometric properties and application of the Perceived Change Scale - Patient version (PCS-P) in a sample of inpatients with mental disorders. Methods: One hundred and ninety-one psychiatric inpatients answered the PCS-P and the Patients' Satisfaction with Mental Health Services Scale (SATIS) and were evaluated in terms of clinical and sociodemographic data. An exploratory factor analysis (EFA) was performed and internal consistency was calculated. The clinical impressions of the patient, family, and physician were correlated with the patient's perception of change. Results: The EFA indicated a psychometrically suitable four-factor solution. The PCS-P exhibited a coherent relationship with SATIS and had a Cronbach's alpha value of 0.856. No correlations were found between the physician's clinical global impression of improvement and the patient's perception of change, although a moderate positive correlation was found between the patients' clinical global impression of improvement and the change perceived by the patient. Conclusions: The PCS-P exhibited adequate psychometric proprieties in a sample of inpatients with mental disorders. The patient's perception of change is an important dimension for evaluation of outcomes in the treatment of mental disorders and differs from the physician's clinical impression of improvement. Evaluation of positive and negative perceptions of the various dimensions of the patient's life enables more precise consideration of the patient's priorities and interests.

CANOPY HEIGHT MODELS TO MONITOR AREAS UNDER DEGRADATION IN MIXED OMBROPHILE

ABSTRACT This research was aimed at providing a study of digital elevation models from Airborne Laser Scanner (ALS) data. The goal was to improve the forest monitoring, or more specifically, arboreal canopy monitoring, which contains the most elevated vegetation of the forest. It is also described as the surface above the canopy top. The region of rain forest between the states of São Paulo and Paraná in Brazil was analyzed. The proposed method employs the ALS system that provides information related to different vegetative cover bedding, to analyze it and reach to estimate for the most elevated stage. The methodology is based on differentiating the identified surfaces in the original set of data. It uses these surfaces with a raster, which was obtained from an interpolation of different sets of points from the surfaces of interest. The raster structure, unlike vector data, allows for processes linked to the digital processing of images. It enables implementation of digital filters over the data. The method helped in reducing the influence of errors during classification and achieving the theoretical surface. The results revealed a coherent relationship with anthropogenic influence such as the introduction of exotic vegetation. We concluded that arboreal vegetation could be an index of conservation for environmental registration and licensing organizations.

The principle of greatest freedom

Elementary particles are the common capital of any being in the universe. However, a being is characterized by its behavior as well as its capital and the principle of least action shows the common behavior of partners that transfer energy. However, the concept of action does not apply to all transfers; what is the action when two men transfer words? Here we show that the “principle of greatest freedom” reveals the common behavior of any partner during nondestructive relationship that is to maximize the number of its accessible states, i.e., its freedom. It gives a common interpretation to quantum mechanics, to wave-particle duality and to relativity. It defines the coherent relationship, which explains why objects behave consistently according to laws and why they construct compound beings that evolve.

Data assimilation and prognostic whole ice-sheet modelling with the variationally derived, higher-order, open source, and fully parallel ice sheet model VarGlaS

We introduce a novel, higher order, finite element ice sheet model called VarGlaS (Variational Glacier Simulator). Contrary to standard procedure in ice sheet modelling, VarGlaS formulates ice sheet motion as the minimization of an energy functional, conferring advantages such as a consistent platform for making numerical approximations, a coherent relationship between motion and heat generation, and implicit boundary treatment. VarGlaS also solves the equations of enthalpy rather than temperature, avoiding the solution of a contact problem. Rather than include a lengthy model spin-up procedure, VarGlaS possesses an automated framework for model inversion. These capabilities are brought to bear on several benchmark problems in ice sheet modelling, as well as a 500 yr simulation of the Greenland ice sheet at high resolution. VarGlaS performs well in benchmarking experiments, and given a constant climate, predicts an overall mass evolution of the Greenland ice sheet that matches well with observational data.