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This paper aims to investigate the improvement of Sn58Bi solder properties by Ni nanoparticle to provide theoretical support in the field of electronic packaging.

In this study, nickel nanoparticles (Ni NPs) were doped into Sn58Bi solder as a reinforcing agent to prepare a composite solder. The wettability of composite solder, melting characteristics of solder alloy, microstructure of joints, mechanical properties and intermetallics growth at the interface were investigated.

Test results show that Ni had little substantial effect on the solders alloy melting temperature yet decreased the alloy undercooling. Notably, Ni enhanced solders wettability on Cu substrates. The spreading area increased by 14% at 0.6 wt.% Ni. The Ni refined the microstructure of Sn58Bi solder joints and inhibited the coarsening of the Bi-rich phase in the solder. At the same time, it also led to the production of free intermetallic compounds, increasing growth of the intermetallic compound (IMC) layer. However, upon surpassing 0.6 wt.% Ni, (Cu, Ni)₆Sn₅ accumulated and formed irregular clumps in the matrix. The grain size of the IMC layer gradually decreased as Ni was added. In shear tests, the fracture of joints occurred mainly inside the solder matrix. Sn58Bi-0.6Ni joints displayed a 40% rise in shear strength and a 25% rise in Vickers hardness. In addition, the appearance of dimples at the fracture indicated the improved flexibility of joints.

In this paper, Ni nanoparticle with different contents were added to Sn58Bi solder to prepare a composite solder, and the properties of the composite solder were investigated from different perspectives.

This study aims to explore the feasibility of adding Si₃N₄ nanoparticles to Sn58Bi and provides a theoretical basis for designing and applying new lead-free solder materials for the electronic packaging industry.

In this paper, Sn58Bi-xSi₃N₄ (x = 0, 0.2, 0.4, 0.6, 0.8, 1.0 Wt.%) was prepared for bonding Cu substrate, and the changes in thermal properties, wettability, microstructure, interfacial intermetallic compound and mechanical properties of the composite solder were systematically studied.

The experiment results demonstrate that including Si₃N₄ nanoparticles does not significantly impact the melting point of Sn58Bi solder, and the undercooling degree of solder only fluctuates slightly. The molten solder spreading area reached a maximum of 96.17 mm², raised by 19.41% relative to those without Si₃N₄, and the wetting angle was the smallest at 0.6 Wt.% of Si₃N₄, with a minimum value of 8.35°. When the Si₃N₄ nanoparticles reach 0.6 Wt.%, the solder joint microstructure is significantly refined. Appropriately adding Si₃N₄ nanoparticles will slightly increase the solder alloy hardness. When the concentration of Si₃N₄ reaches 0.6 Wt.%, the joints shear strength reached 45.30 MPa, representing a 49.85% increase compared to those without additives. A thorough examination indicates that legitimately incorporating Si₃N₄ nanoparticles into Sn58Bi solder can enhance its synthetical performance, and 0.6 Wt.% is the best addition amount in our test setting.

In this paper, Si₃N₄ nanoparticles were incorporated into Sn58Bi solder, and the effects of different contents of Si₃N₄ nanoparticles on Sn58Bi solder were investigated from various aspects.

One hundred and seventy‐eight heroin addicts in reformatory school were sent to one of two rehabilitation treatments: reform through education and labour and therapeutic community (TC)‐based rehabilitation programme. After six months of being discharged, pre‐ and post‐treatment scores on the Addiction Severity Index were compared, and relapse related factors were investigated. Results indicated improvements in both treatments, with the TC‐based rehabilitation programme showing superior improvement overall. Results support the efficacy of the TC‐based rehabilitation programme proving it to be better than reform through labour and education. It is suggested that psychosocial intervention and relapse prevention should be emphasised in the treatment of drug dependence.

Examines the tenth published year of the ITCRR. Runs the whole gamut of textile innovation, research and testing, some of which investigates hitherto untouched aspects. Subjects discussed include cotton fabric processing, asbestos substitutes, textile adjuncts to cardiovascular surgery, wet textile processes, hand evaluation, nanotechnology, thermoplastic composites, robotic ironing, protective clothing (agricultural and industrial), ecological aspects of fibre properties – to name but a few! There would appear to be no limit to the future potential for textile applications.

Extant literature has indicated that government support is one of the main drivers of international expansion of Chinese multinational enterprises. However, research on the influence of governors on firm internationalization is still limited. Drawing upon the institution-based view, we theorize a novel concept of institutional enablement to illustrate the influence of a governor's pro-market ideology on Chinese firms' internationalization.

We analyze the relationship between a governor's pro-market ideology (consisting of a pro-market political ideology, an overseas educational background and a business background) and firm internationalization with a sample of Chinese public companies during 2014–2017.

We find a direct and positive effect of a governor's pro-market ideology on firm internationalization. We also find an indirect and positive effect of a governor's pro-market ideology through regional, inward foreign direct investment.

To the best of our knowledge, this paper is the first to investigate an underexplored question of the impact of governors on firm internationalization and to develop a novel concept of institutional enablement, based on discursive institutionalism.

The purpose of this study is to examine Chinese international students' narrative stories, experiences and racial dynamics while studying in the United States to argue that Chinese international students navigate multi-dimensional transitions and experiences in different stages. This study uses an AsianCrit lens to address the gap in existing research focusing on Chinese international students' narratives and experiences.

Narrative inquiry with a social constructivist paradigm was used to provide an in-depth exploration of Chinese international students' navigation and negotiation in multi-dimensional experiences. Three phases of semi-structured interviews and journal entries were utilized to examine participants' experiences and struggles while studying in the United States. Descriptive coding, deductive coding and restorying were used to analyze and feather narrators' voices and stories for interpretation.

The findings in this qualitative study demonstrate that Chinese international students have unique backgrounds, and their backgrounds shape their multi-dimensional transitions and experiences in the present and the future. The findings address students' nuanced experiences in academic transitions and non-academic transitions with an AsianCrit lens.

The study calls for higher education institutions to promote intercultural and international training for faculty and staff to better understand and support the unique needs of international students.

Using Multiple and Multi-dimensional Transitions theory with an AsianCrit lens helps make sense of the intersection of international student status, geopolitical tensions, racial dynamics and international student experiences.

The precise segmentation of brain tumors is the most important and crucial step in their diagnosis and treatment. Due to the presence of noise, uneven gray levels, blurred boundaries and edema around the brain tumor region, the brain tumor image has indistinct features in the tumor region, which pose a problem for diagnostics. The paper aims to discuss these issues.

In this paper, the authors propose an original solution for segmentation using Tamura Texture and ensemble Support Vector Machine (SVM) structure. In the proposed technique, 124 features of each voxel are extracted, including Tamura texture features and grayscale features. Then, these features are ranked using the SVM-Recursive Feature Elimination method, which is also adopted to optimize the parameters of the Radial Basis Function kernel of SVMs. Finally, the bagging random sampling method is utilized to construct the ensemble SVM classifier based on a weighted voting mechanism to classify the types of voxel.

The experiments are conducted over a sample data set to be called BraTS2015. The experiments demonstrate that Tamura texture is very useful in the segmentation of brain tumors, especially the feature of line-likeness. The superior performance of the proposed ensemble SVM classifier is demonstrated by comparison with single SVM classifiers as well as other methods.

The authors propose an original solution for segmentation using Tamura Texture and ensemble SVM structure.

No studies in the extant literature have explored the role of media richness, i.e., the ability of media to enhance understanding among communication partners in a timely manner, in determining customer loyalty to mobile instant messaging (MIM). Grounded in media richness theory, the purpose of this paper is to examine how media richness influences customer perceived values, consequently contributing to customer loyalty to MIM.

Collecting data by an online survey, the authors apply partial least square procedures for hypothesis testing.

The authors obtain the following findings: multiple cues are positively related to functional value; immediate feedback is positively related to social value; personal focus is positively related to self-expressive value; language variety is positively related to all the above values that lead to user loyalty; and language variety has the strongest effect on user loyalty to MIM.

A first attempt to examine the impact of media richness on user loyalty to MIM, this study provides insights for MIM service providers to make decisions to build loyal user bases.

The purpose of this paper is to assess the hydrogen embrittlement sensitivity of carbon gradient heterostructure materials and to verify the reliability of the scratch method.

The surface-modified layer of 18CrNiMo7-6 alloy steel was delaminated to study its hydrogen embrittlement characteristics via hydrogen permeation, electrochemical hydrogen charging and scratch experiments.

The results showed that the diffusion coefficients of hydrogen in the surface and matrix layers are 3.28 × 10⁻⁷ and 16.67 × 10⁻⁷ cm²/s, respectively. The diffusible-hydrogen concentration of the material increases with increasing hydrogen-charging current density. For a given hydrogen-charging current density, the diffusible-hydrogen concentration gradually decreases with increasing depth in the surface-modified layer. Fracture toughness decreases with increasing diffusible-hydrogen concentration, so the susceptibility to hydrogen embrittlement decreases with increasing depth in the surface-modified layer.

The reliability of the scratch method in evaluating the fracture toughness of the surface-modified layer material is verified. An empirical formula is given for fracture toughness as a function of diffused-hydrogen concentration.

The purpose of this paper is to study the dynamic vibrations of the tethered satellite system (TSS).

The energy principle and the variational approach are used to establish the dynamic equations of the TSS. By introducing new generalized coordinates, the equations are transformed into the Hamiltonian system. Then, the symplectic Runge-Kutta (SRK) method is used to solve the canonical equations.

The influence of the tether length on the dynamic behavior of the TSS is very important.

The dynamic responses of the TSS are obtained by using the SRK method.