scholarly journals Electrospinning Mechanism of Nanofiber Yarn and Its Multiscale Wrapping Yarn

Polymers ◽  
2021 ◽  
Vol 13 (18) ◽  
pp. 3189
Author(s):  
Taohai Yan ◽  
Yajing Shi ◽  
Huimin Zhuang ◽  
Yu Lin ◽  
Dongdong Lu ◽  
...  

To analyze the feasibility of electrospinning nanofiber yarn using a wrapping yarn forming device, electrospun nanofiber-wrapped yarns and multiscale yarns were prepared by self-made equipment. The relationship between the surface morphology and properties of yarn and its preparation process was studied. The process parameters were adjusted, and it was found that some nanofibers formed Z-twisted yarns, while others showed exposed cores. To analyze the forming mechanism of electrospun nanofiber-wrapped yarn, the concept of winding displacement difference in the twisted yarn core A was introduced. The formation of nanofiber-wrapped structural yarns was discussed using three values of A. The starting point of each twist was the same position when A = 0 with a constant corner angle β. However, the oriented nanofiber broke or was pulled out from the gripping point when it was twisted, and it appeared disordered. The forming process of electrospun nanofiber-wrapped yarn displayed some unique phenomena, including the emission of directional nanofibers during collection, fiber non-continuity, and twist angle non-uniformity. The conclusions of this research have theoretical and practical value to guide the industrial preparation of nanofiber yarns and their wrapped yarns.

2014 ◽  
Vol 490-491 ◽  
pp. 256-261 ◽  
Author(s):  
F.K. Cui ◽  
G.P. Yan ◽  
H. Liu ◽  
X.Q. Wang ◽  
Y.X. Li

For revealing the forming mechanism in micro level and for establishing the relationship between macroscopic deformation and microscopic changes, impact experiment of material property is conducted under the high speed cold roll-beating condition based on the plastic deformation mechanism of metal material, Based on the Zener-Hollomon constitutive relation, the macro change model is established, and the parameters of the 40 Cr are obtained according to the experimental data. Based on the model of microstructure evolution of dislocation density, the relation between macroscopic change and microscopic change is established, which provides the theoretical support for the forming process in micro level and revels the relationship between macro deformation and micro changes in the forming process of high speed cold roll-beating.


2019 ◽  
Author(s):  
Valentina Escotet Espinoza

UNSTRUCTURED Over half of Americans report looking up health-related questions on the internet, including questions regarding their own ailments. The internet, in its vastness of information, provides a platform for patients to understand how to seek help and understand their condition. In most cases, this search for knowledge serves as a starting point to gather evidence that leads to a doctor’s appointment. However, in some cases, the person looking for information ends up tangled in an information web that perpetuates anxiety and further searches, without leading to a doctor’s appointment. The Internet can provide helpful and useful information; however, it can also be a tool for self-misdiagnosis. Said person craves the instant gratification the Internet provides when ‘googling’ – something one does not receive when having to wait for a doctor’s appointment or test results. Nevertheless, the Internet gives that instant response we demand in those moments of desperation. Cyberchondria, a term that has entered the medical lexicon in the 21st century after the advent of the internet, refers to the unfounded escalation of people’s concerns about their symptomatology based on search results and literature online. ‘Cyberchondriacs’ experience mistrust of medical experts, compulsion, reassurance seeking, and excessiveness. Their excessive online research about health can also be associated with unnecessary medical expenses, which primarily arise from anxiety, increased psychological distress, and worry. This vicious cycle of searching information and trying to explain current ailments derives into a quest for associating symptoms to diseases and further experiencing the other symptoms of said disease. This psychiatric disorder, known as somatization, was first introduced to the DSM-III in the 1980s. Somatization is a psycho-biological disorder where physical symptoms occur without any palpable organic cause. It is a disorder that has been renamed, discounted, and misdiagnosed from the beginning of the DSMs. Somatization triggers span many mental, emotional, and cultural aspects of human life. Our environment and social experiences can lay the blueprint for disorders to develop over time; an idea that is widely accepted for underlying psychiatric disorders such as depression and anxiety. The research is going in the right direction by exploring brain regions but needs to be expanded on from a sociocultural perspective. In this work, we explore the relationship between somatization disorder and the condition known as cyberchondria. First, we provide a background on each of the disorders, including their history and psychological perspective. Second, we proceed to explain the relationship between the two disorders, followed by a discussion on how this relationship has been studied in the scientific literature. Thirdly, we explain the problem that the relationship between these two disorders creates in society. Lastly, we propose a set of intervention aids and helpful resource prototypes that aim at resolving the problem. The proposed solutions ranged from a site-specific clinic teaching about cyberchondria to a digital design-coded chrome extension available to the public.


Author(s):  
Nathan Wildman

The relationship between fundamentality and modality remains criminally underexplored. In particular, there are several significant questions about fundamentality’s modal strength that remain unanswered. For example, if something is fundamental is it necessarily so? That is, could something be fundamental in one possible world and derivative in another? And how would the acceptance of contingent fundamentality square with commitments to contingentism (or, for that matter, necessitism) about the existence of the fundamentalia? Chapter 14 makes some headway towards addressing these questions. It does so by exploring the contingent fundamentality thesis, according to which it is possible that something is possibly fundamental and possibly derivative. In this way, the chapter represents a starting point for examining broader issues about the relationship between fundamentality and modality.


2013 ◽  
Vol 788 ◽  
pp. 57-60
Author(s):  
Chun Cao ◽  
Chun Dong Zhu ◽  
Chen Fu

Warm pressing forming technology has been gradually applied to the forming of automotive friction materials. How to ensure product performance to achieve the target at the same time achieve the maximum energy saving is the research focus of this study. In this paper, by using finite element method, the field of automotive friction materials in warm pressing forming was analyzed, reveals the relationship between the temperature field and the heating temperature/heating time. Furthermore, the energy consumption was analyzed and compared it with hot pressing forming process. The results will have significant guiding to the process optimization in warm pressing forming.


2021 ◽  
Vol 11 (9) ◽  
pp. 3827
Author(s):  
Blazej Nycz ◽  
Lukasz Malinski ◽  
Roman Przylucki

The article presents the results of multivariate calculations for the levitation metal melting system. The research had two main goals. The first goal of the multivariate calculations was to find the relationship between the basic electrical and geometric parameters of the selected calculation model and the maximum electromagnetic buoyancy force and the maximum power dissipated in the charge. The second goal was to find quasi-optimal conditions for levitation. The choice of the model with the highest melting efficiency is very important because electromagnetic levitation is essentially a low-efficiency process. Despite the low efficiency of this method, it is worth dealing with it because is one of the few methods that allow melting and obtaining alloys of refractory reactive metals. The research was limited to the analysis of the electromagnetic field modeled three-dimensionally. From among of 245 variants considered in the article, the most promising one was selected characterized by the highest efficiency. This variant will be a starting point for further work with the use of optimization methods.


2004 ◽  
Vol 5 (1) ◽  
pp. 43-58
Author(s):  
Jeffrey S. Galko ◽  

The ontological question of what there is, from the perspective of common sense, is intricately bound to what can be perceived. The above observation, when combined with the fact that nouns within language can be divided between nouns that admit counting, such as ‘pen’ or ‘human’, and those that do not, such as ‘water’ or ‘gold’, provides the starting point for the following investigation into the foundations of our linguistic and conceptual phenomena. The purpose of this paper is to claim that such phenomena are facilitated by, on the one hand, an intricate cognitive capacity, and on the other by the complex environment within which we live. We are, in a sense, cognitively equipped to perceive discrete instances of matter such as bodies of water. This equipment is related to, but also differs from, that devoted to the perception of objects such as this computer. Behind this difference in cognitive equipment underlies a rich ontology, the beginnings of which lies in the distinction between matter and objects. The following paper is an attempt to make explicit the relationship between matter and objects and also provide a window to our cognition of such entities.


2015 ◽  
Vol 44 (4) ◽  
pp. 687-705 ◽  
Author(s):  
RACHAEL DOBSON

AbstractThis article argues that constructions of social phenomena in social policy and welfare scholarship think about the subjects and objects of welfare practice in essentialising ways, with negativistic effects for practitioners working in ‘regulatory’ contexts such as housing and homelessness practice. It builds into debates about power, agency, social policy and welfare by bringing psychosocial and feminist theorisations of relationality to practice research. It claims that relational approaches provide a starting point for the analysis of empirical practice data, by working through the relationship between the individual and the social via an ontological unpicking and revisioning of practitioners' social worlds.


2014 ◽  
Vol 494-495 ◽  
pp. 457-460 ◽  
Author(s):  
Bin Hu ◽  
Xue Dao Shu ◽  
Peng Hui Yu ◽  
Wen Fei Peng

The paper is based on the newest hollow railway axle, which utilizes the Pro/E designed multi-wedge cross wedge rolling (MCWR) model, utilizes the finite element analysis software DEFORM-3D to complete the numerical simulation about the whole stage of the hollow railway axle forming process, and analyzes the strain rule at the broadening stage of the hollow railway axle, especially conducts a detailed research on forming character into the strain rule at the multi-wedge transition stage, and finally gets the strain forming mechanism of the hollow railway axle at the broadening stage. The result of the research on the strain rule poses great scientific significance on enhancing the product quality and the production efficiency of the hollow railway axle, and improving the theory of multi-wedge cross wedge rolling.


2008 ◽  
Vol 7 (1) ◽  
pp. 64-76
Author(s):  
Andy Stirrup

This paper considers an implicit trend in youth ministry to present Jesus as the archetypal superhero and asks if this is a valid and a helpful approach. The paper examines the relationship between the biblical category of hero and the contemporary notion of superhero and a broader appreciation of the use of myth for communicating Christian apologetics as seen in Lewis and Tolkien. The starting point for the paper is that an arguable starting point for the creation of Superman is in the epic character of Hercules and the biblical hero Samson. Through an examination of biblical and other Near East material the paper calls for a deeper and more nuanced appreciation of the relevance of modern western myth in the task of communicating theological narratives and concepts.


2021 ◽  
Vol 31 (2) ◽  
pp. 307-321
Author(s):  
Luke O’Sullivan ◽  

The concept of civilisation is a controversial one because it is unavoidably normative in its implications. Its historical associations with the effort of Western imperialism to impose substantive conditions of life have made it difficult for contemporary liberalism to find a definition of “civilization” that can be reconciled with progressive discourse that seeks to avoid exclusions of various kinds. But because we lack a way of identifying what is peculiar to the relationship of civilisation that avoids the problem of domination, it has tended to be conflated with other ideas. Taking Samuel Huntington's idea of a “Clash of Civilisations” as a starting point, this article argues that we suffer from a widespread confusion of civilisation with “culture,” and that we also confuse it with other ideas including modernity and technological development. Drawing on Thomas Hobbes, the essay proposes an alternative definition of civilisation as the existence of limits on how we may treat others.


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