190 research outputs found
ヘモグロビンM症の病態生化学的研究
Two new 3-fold interpenetrated 3D microporous metal-organic coordination polymers (MOCPs) of Cu(II), [Cu<SUB>3</SUB>(bipy)<SUB>1.5</SUB>(2,6-ndc)<SUB>3</SUB>]<SUB>n</SUB> (1) and {[Cu(bpe)<SUB>0.5</SUB>(2,6-ndc)]·0.5H<SUB>2</SUB>O}<SUB>n</SUB> (2) (bipy = 4,4′-bipyridine; bpe = 1,2-bis(4-pyridyl)ethane; and 2,6-ndc = 2,6-naphthalenedicarboxylate), have been synthesized using a mixed-ligand system and structurally characterized by single-crystal X-ray diffraction study. Room-temperature reaction of Cu(II) with bipy and 2,6-ndc affords 1, whereas reaction with bpe and 2,6-ndc yields 2. Structure determination reveals that in both cases, a 2D square grid made by Cu(II) and 2,6-ndc with the aid of Cu<SUB>2</SUB>(CO<SUB>2</SUB>)<SUB>4</SUB> paddlewheel building block is connected by bipy (1) or bpe (2) organic pillar results 3D Α-polonium type frameworks. Framework 1 is rigid and robust without any guest molecules, whereas 2 is flexible, realized by the guest induced structural transformations. Both the frameworks show high thermal stability. Framework 1 and dehydrated form of 2, i.e 2′ contains 16.6% and 21.4% void space, respectively and Langmuir surface area calculated from nitrogen adsorption study for 1 and 2′ is 113.0 and 337.5 m<SUP>2</SUP>/g, respectively. Both the frameworks can store approximately 1 wt % of molecular hydrogen at 77 K and 15 bar, in particular, the density of adsorbed hydrogen in 1 is one of the highest reported so far in porous MOCPs. Compounds 1 and 2′ can also store 11.0 and 13.2 wt % carbon dioxide at 195 K
Crystallographic studies of gas sorption in metal-organic frameworks.
Metal-organic frameworks (MOFs) are a class of porous crystalline materials of modular design. One of the primary applications of these materials is in the adsorption and separation of gases, with potential benefits to the energy, transport and medical sectors. In situ crystallography of MOFs under gas atmospheres has enabled the behaviour of the frameworks under gas loading to be investigated and has established the precise location of adsorbed gas molecules in a significant number of MOFs. This article reviews progress in such crystallographic studies, which has taken place over the past decade, but has its origins in earlier studies of zeolites, clathrates etc. The review considers studies by single-crystal or powder diffraction using either X-rays or neutrons. Features of MOFs that strongly affect gas sorption behaviour are discussed in the context of in situ crystallographic studies, specifically framework flexibility, and the presence of (organic) functional groups and unsaturated (open) metal sites within pores that can form specific interactions with gas molecules
On Fluctuation of Social and Economic Condition and Its Influence Upon "Stature and Growth" of Children
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Exploring the relationship between work-family balance and employee engagement amongst workers in Bahrain
This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University LondonThis exploratory study examines the relationship between work-family balance and employee engagement among Bahraini workers. An overwhelming number of studies have been conducted in the West. In contrast, there is a paucity of research on work-family balance and employee engagement in the Middle East region, particularly in Bahrain. The objectives of the study include: to explore the definitions of work-family balance and its effect on employee engagement amongst workers in Bahrain; to examine the ideology surrounding employees’ role in the workplace and family and how it affects their work culture; to ascertain the extent to which institutional and organisational policies promote or hinder work-family balance and employee engagement amongst Bahrainis in the workplace, and; to assess the adaptive and coping strategies of Bahraini employees on their work-family balance and work engagement. In order to achieve these objectives, qualitative research was conducted using semi-structured indepth interviews with 50 Bahraini workers (male and female) across three major cities in Bahrain. Drawing on the data collected, two important contributions are made to the field of study. First, the study provides empirical evidence of the existing relationship between work-family balance and employee engagement in Bahrain. The findings illustrate how Bahraini employees define work-family balance and employee engagement as quality time and availability, autonomy and control, and as an integration of work and family domains. The findings also revealed how role expectations at work and home affect the ability of Bahraini employees to achieve work-family balance and employee engagement. In other words, there is an overarching relationship between individual roles and their ability to manage their work and family obligations, which includes being engaged. The findings highlight the various institutional and Organisational policies shaping the attainment of work-family balance and employee engagement amongst workers in Bahrain. The findings also reveal that Bahraini workers grapple with work-family conflict and struggle to cope with their job demands and family obligations. It further highlights the unique coping strategies adopted by Bahraini workers to deal with work-family conflict. Specifically, the impact of patriarchy on how men and women perform their duties and roles at work and home is discussed. In other words, the findings reveal that the masculinity features that play out in Bahraini society significantly impact the ability to achieve work-family balance and work engagement. Second, the study provides theoretical contributions by establishing the relationship between work-family balance and employee engagement. The study provides evidence that there is a positive relationship between WFB and employee engagement, given that employees who successfully manage the two domains tend to be satisfied with their jobs, translating into work engagement. For most in this study, such relationships could not be achieved due to several factors affecting work-family balance, especially the increasing job and family demands. More specifically, the study provides initial support for the job demand-resources model and its relevance to understanding work-family balance and employee engagement. It is evident from the findings that employees have increasing job demands, which often conflicts with the home demands (especially for women). Although the JD-R model focuses expressly on the relationship between job demand and job resources necessary to enhance employees’ productivity and performance, it overlooks the impact of family demands on the worker’s ability to perform work-related task. Despite having the necessary job resources, employees may be unproductive or disengaged if the resources needed for their non-work-related responsibilities are absent. Therefore, employees seek adequate job resources to deal with their job demands, as well as having sufficient home resources that help them fulfil their familial responsibilities
An Approach to the Health Guidance about How to Prevent Nearsightedness : Nearsightedness and Junior High School Students
Theoritical Characterization of Different Samples Using Rotating Polarizer and Analyzer Ellipsometer with A Fixed Compensator
Ellipsometry is an extremely powerful tool for the study the optical properties of materials with high optical data precision in measurement. Being accurate, fast and non-destructive in data acquisition and characterization of the samples, ellipsometry has been widely applied especially in the scientific research labs and microelectronic industry with continuous efforts and progress made by developing different theoretical models and experimental techniques. In this work, an ellipsometer using a fixed phase retarder and a rotating polarizer and analyzer at any speed ratio is presented. Muller formalism is employed to extract Stokes parameters from which the intensity received by the detector is obtained. A comparison between different configurations is held regarding the effect of the noise on the results extracted from each one and the uncertainties in the ellipsometric parameters as functions of the uncertainties of the Fourier coefficients. Moreover, a set of ellipsometric configurations using a rotating polarizer, compensator, and analyzer at any speed ratio is studied. All configurations are applied to bulk c-Si and GaAs to calculate the real and imaginary parts of the refractive index of the samples. The comparison among different configurations reveals that rotating compensator-analyzer configuration corresponds to the minimum error in the calculated optical parameters
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