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The material constitutive equation of 25CrMo4 steel was established through an isothermal compression experiment. First, a thermal compression experiment was carried out with a Gleeble-3500 thermal simulator to study the thermoplastic deformation behaviour of 25CrMo4 steel at various temperatures (850, 950, 1050, and 1150 °C) and strain rates (0.01, 0.1, 1.0, and 10 s−1). The measured true stress–strain curve showed that when the temperature is constant, the flow stress increases with the strain rate, whereas when the strain rate is constant, the flow stress decreases with the temperature. Then, the constitutive model of peak stress of 25CrMo4 was established after analyzing the stress and strain statistics. The model parameters were optimized. The accuracy of the flow stress constitutive model was verified by comparing the flow stress prediction model with the experimental results. The hot forging process of the inner core wheel was numerically simulated based on DEFORM-3D v11 software, and the parameters of this process were formulated by analyzing the metal flow rate and equivalent stress and strain fields. [ABSTRACT FROM AUTHOR]

The efficiency of photocatalysts depends largely on the accessibility of reaction species to the active centre, the electron transfer and geometric matching between the active surface of the catalyst and reaction species. In this work, we successfully synthesized and designed one two-dimensional Mn(II) MOF with [Mn2(H2L1)(H2O)2(DMF)2]n·(CH3CH2OH)n (HSTC 3) by using MnCl2·4H2O and 5,5′-(anthracene-9,10-diyl)diisophthalic acid (H4L1), in which the adjacent layers are stacked with weak interactions, and the huge gap leads to the interpenetration between layers to form a 2D + 2D → 3D interpenetration frame. Based on the particularity of the structure of HSTC 3, ultrasonic wall breaking methods were tried to successfully peel HSTC 3 into nanosheets (HSTC 3-NS), thus achieving a significant improvement in a series of optoelectronic properties due to exposure to more active centres for HSTC 3-NS. These results significantly enhance the photocatalytic selective oxidation of thioether. This study provides a new insight into the post-synthesis modification of MOF photocatalyst and their application in photocatalytic organic synthesis. [ABSTRACT FROM AUTHOR]

Taking the railway passenger car water tank as the research object,the bidirectional fluid-solid coupling method is used to model and numerically analyze the liquid impact sloshing problem in the passenger car tank using the finite element analysis software ANSYS Workbench. By studying the continuous impact load on the water tanks with different water contents in the longitudinal direction of the vehicle,the change history of the tank structure stress with time and the deformation history of the tank structure with time are obtained. The results show that the maximum stress and maximum displacement of the box gradually increase with the increase of water content. Through analysis,the weak position of the box structure is determined,By plotting the comparison curve between the test value and the simulation value of each measuring point,The consistency between the calculation model of the water tank and the actual model was verified. Shows that the two-way fluid-solid coupling method and water tank model used in this paper have good reliability,which provides a reliable analysis method for the design and optimization of the water tank structure of the railway passenger car.

This article documents five refugee families and their children's efforts to reestablish themselves in an urban school context in the US. A thematic analysis of the families' negotiation with the urban school system, the language programmes and their home engagement practices suggests that they were subjected to symbolic violence brought upon by the precarious context of reception, the monolingual ideologies and the hegemonic practices of the urban schools and resettlement policies and agencies. Such symbolic violence systematically fractured their language learning, educational success, and upward social mobility. Therefore, despite their divergent paths of immigration and resettlement, the children shared similar stories of system blockage, inertia, and fragmentation. These shared trajectories suggest the need for multi-layered changes to remove blockages in the education and immigration system, transform the dispositions and practices of the key players, including policy makers, school administrators and teachers, and raise critical consciousness among the refugees.

This research frames student teachers' professional identity formation through the lenses of emotions and dilemmas based on semi-structured interviews and emotional journals. Utilizing grounded-theory analysis method, this paper reveals a pattern of the emotional trajectories that the six student teachers experienced from the beginning to the end of the practicums: eagerness and anxiety at the beginning of the teaching practicums, shock and embarrassment immediately after the student teaching, anger and puzzlement at the middle of the internship, helplessness and loneliness toward the end of the practicums, and guilt and regret after the teaching practice. Furthermore, the participants were faced with four dilemmas: (1) tensions between classroom authority and the ethic of caring, (2) acting as a community member or an "outsider," (3) working as an office assistant or a "real teacher," (4) conflicting pedagogies regarding teaching different academic performance levels of students. All these dilemmas contribute to the complexity of the teaching practicum in China. Finally, implications for teacher education, especially for preservice teachers' pedagogy of identity and ethical professionalism, are discussed.

The rapid increase of Asian immigrant students in Canadian classrooms demands more systematic and increased language support to ensure all English language learners (ELLs) achieve success in school. However, research has found mixed results on the usefulness of current English as a Second Language (ESL) support programs and a growing dissatisfaction among students and parents about ESL, suggesting further investigation is needed to improve the provision of ESL in the schools. This paper details how one school and one ESL teacher responded to the needs of newly arrived Asian (i.e., Chinese) ELL students by documenting the school's and teacher's journey in revamping the pull-out ESL program into a culturally responsive English for Academic Purposes (EAP) program with a focus on immersion, community engagement, and a pedagogy of cultural reciprocity. The case has important implications for redesigning current ESL programs in the context of changing immigration.

This article reports on a critical qualitative case study of an EMI-based, underresourced public school in Nepal through Bourdieu's lens of linguistic capital. As the data analysis revealed, parents, students, and teachers regarded EMI as a privileged form of linguistic capital for developing advanced English skills, enhancing educational achievements and access to higher education, and increasing the chance of upward social and economic mobility. In contrary to these rosy perceptions of EMI with overtly superficial promises, switching to EMI, without enough teacher preparation and infrastructure support in the school, had contributed to several unplanned negative outcomes, including a contested process of developing the English proficiency. Despite the school's claim of offering EMI education, Nepali was the actual language of instruction in the school due to teachers' lack of proficiency in English and the school's inadequate resources and preparedness for a shift to EMI. As a result, the students developed neither the content knowledge nor English language skills. Therefore, rather than being an educational equalizer, EMI has served to (re)produce linguistic marginalization and educational inequality and injustice for children from a lower socioeconomic status. We suggest critical reflection on EMI adoption and reenvision "sustainable additive multilingualism" in such contexts (Erling et al., 2016).

Based on the theoretical perspectives of socio-constructivism and language socialization, this study reports two Chinese Canadian first grader's experiences of language and literacy learning in and out of school in a unique sociocultural setting where they were "the mainstream." The article examines the students' reading and writing practices in school and at home, as well as their parents' and teachers' thoughts, beliefs, resources, and concerns regarding their literacy learning. The findings suggest that there exists great linguistic and cultural discontinuity between the Chinese children's school and home language and literacy experiences. The children view school and home literacies as separate entities rather than a continuum. Such perceptions further widened the gaps between their development of "school literacy" which is mediated through English language and culture and that of "home literacy" which is mediated through Chinese language and culture. These children's learning experiences were also influenced by the conflicts between the school's cultural values and those of their families, which include dissensions on biliteracy expectations, homework, parenting, and instructional approaches (e.g., the use of drawing and free play). Living between two separate worlds of school and home, the students are often burdened with the consequences of the cultural clashes and become "sites of struggle" between teachers and parents, and hence, are placed in a dangerous position for potential failure at school. (Contains 2 figures.)

This article reports on a sample of 26 middle-class Chinese immigrant parents' perspectives on their children's reading, writing, mathematics learning, and homework, and on the parents' involvement in and communication with mainstream American schools. Findings suggested both consistencies and discrepancies between their beliefs and practices. Areas of discrepancies include their reported involvement in their children's reading and their attitudes toward homework. However, the parents were more consistent in their beliefs and practices in writing and mathematics involvement. These consistencies and discrepancies may be influenced by the parents' familiarity with school instructions in the particular skill areas. These findings argue for more effort to enhance Chinese parents' knowledge base on how American school functions and to build stronger school-home communication and collaboration. (Contains 10 tables and 2 endnotes.)

Persistent educational inequity for immigrant and refugee students and their families calls for instructional practices centering on access, quality, and social justice. Drawing on two qualitative case studies, this article examines how three U.S. urban school teachers attended to the systemic inequalities and unique challenges confronting immigrant and refugee students both inside their classrooms and outside the school. Our analyses show that the teachers strategically enacted various critical instructional practices, including linguistically responsive pedagogy, translanguaging, and sociopolitically responsive pedagogy. The teachers' agentic practices have important implications for teacher education and professional development for immigrant and refugee learners in urban settings. [ABSTRACT FROM AUTHOR]

Questions Kouritzin's discussion of researcher subjectivity in life history research and argues that life history research should have a transformative agenda. (Author/VWL)

Despite recent scholarly advancements in teaching English as an international language (EIL), its implementation in TESOL classrooms has been challenging and limited. Because English teachers play a significant role in EIL implementation in their daily lessons, preparing EIL-oriented teachers becomes critical. This article outlines major developments in EIL and their implications for teacher competence and discusses the ideological challenges in integrating EIL in teacher education. It concludes with a detailed description of a three-step EIL-oriented pedagogy for TESOL teacher education courses and programs that aims to foster teachers' linguistic self-respect, build their pedagogical competence for plurilingual teaching, and transform their classrooms.

Immigrant youths' frequent and skillful use of new media technologies outside of school has generated discussion on the need to integrate their expertise in formal literacy instruction in school. This commentary argues that braiding old and new literacies for English learners in empowering ways needs to be guided by a connection to the future (new literacies for social and academic purposes) and a link to the old (traditional print literacy skills). Such a dual focus is necessary to develop an integrated pedagogical design that engages learners in using the new tools for acquiring both new and old literacy skills. Active facilitation of transmediation between social and academic purposes of new literacies and between old and new literacies relies on both explicit instruction of higher level thinking skills and literacy strategies for online and offline engagement and teacher expert scaffolding of applications of these skills in meaningful learning tasks.