bluuebunny/crossref_metadata_2025_split huggingface dataset:
Modeling of SAPO-18/34 intergrowth crystal structure
Authors: Slawinski Wojciech , Wragg David , Akporiaye Duncan , Fjellvag Helmer 
Published: November 2015

Aluminophosphate framework structures have been widely studied because of their many technological applications. The most significant application of aluminophosphate type framework catalysts is in the methanol-to-olefin (MTO) conversion process [1], catalysed by SAPO-34 (the silicoaluminophosphate form of the chabazite (CHA) zeolite framework with silicon substituted into its structure). The effectiveness of SAPO-34 in the MTO process is due to both the shape selective properties of the framework and the concentration and strengths of the acid sites created by silicon substitution [2]. Another aluminophosphate framework MTO catalyst is SAPO-18 (zeolite framework type (AEI)), which has a very closely related structure to SAPO-34 and can form intergrowths with it. It has been suggested that the level of intergrowth can affect the efficiency of the MTO process [3], however, assessment of the level of intergrowth has remained difficult. We present a consistent model of the crystal structure of SAPO-18/34 family members which can accurately determine the level of intergrowth. The model utilises two types of stacking fault: Displacement and Growth which have significantly different effects on the diffraction pattern. A series of powder diffraction patterns is calculated using the Discus software package. Changes in the level of intergrowth and stacking fault type strongly affect the calculated pattern. A series of patterns has been calculated to illustrate this. The structure of an intergrown SAPO-34 sample with 4.8% Si content is modelled and refined using Displacement stacking faults. An example of "defect-free" AlPO-18 (0% Si content) is then presented. Refinement of the model shows that even this contains a small amount of stacking faults. Finally, a simple method for defect level estimation is proposed based on FWHM (Full Width at Half Maximum) ratios for selected Bragg reflections.
Complementary XRD and XAFS Studies of Double Metal Cyanides catalysts
Authors: Jablonska Krystyna , Demchenko Iraida , Dynowska Elzbieta , Chrusciel Arkadiusz , Janik Jaroslaw 
Published: November 2015

Highly disordered materials exhibit diversity of the functional properties which are of interest of nowadays technology. The example of such materials is the group of a non-stoichiometric composite transition metal complex salts, known as double metal cyanides (DMC). These materials are used as the industrial catalysts and form an interesting family of porous molecular materials with large fraction of the amorphous phase. This fraction may be obtained by introduction to the crystalline zinc hexacyanocobaltate (III) (Zn3[Co(CN)6]2·nH2O) organic ligands of different size. Depending on the type of ligands the catalysts exhibit different levels of activity. The crystalline zinc hexacyanocobaltate exhibits only very weak catalytic properties. The others have a considerably high activity, which is their key feature. Although the said group of catalysts is successfully used and progressively developed for decades, the knowledge on the molecular nature of their particularly high activity and selectivity is modest and limited to some phenomenological hypotheses based on overall chemical premises. The attempt to formulate important for DMC catalysts relationship between the concentration of amorphous phase and their activity as well the influence of an organic ligand presence on formation of amorphous phase, suspected to be responsible for catalytic properties, will be presented. The base for this is the reliable characterization of such materials which requires application of several methods providing complementary information. The application of x-ray diffraction and absorption will be discussed and the benefit of each method will be described. Acknowledgments: Research funded in part by the Projects BSR, Science Link and Innotech K2/IN2/21/181982/NCBR/ 12(K-DMC). Financial support from the EU FP7 under the grant agreement REGPOT-CT-2013-316014 is gratefully acknowledged. Jaroslaw Janik is a Fellow of the project "PhD Scholarships - an investment in faculty Opole province" co-financed by the European Union under the European Social Fund.
A system for time-resolved XRD measurements on hydrogen absorption processes
Authors: Machida Akihiko , Higuchi Kensuke , Katayama Yoshinori , Sakaki Kouji , Kim Hyunjeong , Nakamura Yumiko 
Published: November 2015

To improve performance of hydrogen storage materials, it is essential to understand detailed mechanism of hydrogenation and dehydrogenation reactions. In-situ powder diffraction measurements provide direct information about structural changes accompanying the reactions. We therefore installed a time-resolved x-ray diffraction (XRD) system at a beamline BL22XU at the SPrign-8, a synchrotron radiation facility in Japan. The system was equipped with two area detectors, a flat panel sensor for precise structural analyses and a high speed video camera connected to an x-ray image intensifier for observation of rapid phase changes. Maximum frame rate for the flat panel sensor and high-speed video camera was 2 fps and 125 fps (effective), respectively. A sample cell was connected to a hydrogen supply system. Opening of upstream valve of the sample cell or a change of the pressure at the sample triggered the recording of the diffraction patterns. The pressure of hydrogen gas was limited to 1 MPa. To demonstrate the performance of the system, we have performed time-resolved XRD experiments for LaNi4.5Al0.5. LaNi5 exhibits the significant broadening of the diffraction peaks by hydrogen absorption; however, LaNi4.5Al0.5 shows the no significant broadening. We have succeeded in the measurements of the structural change from the solid solution phase to the hydride phase and have found the formation of the transient intermediate phase on this reaction process. The system is currently used to study several materials. This work was partly supported by New Energy and Industrial Technology Development Organization (NEDO) under "Advanced Fundamental Research Project on Hydrogen Storage Materials".
"""Objective"" Evaluation of Macromolecular Models"
Authors: Ten Eyck Lynn , Perez Martin 
Published: November 2015

Evaluation of the accuracy and quality of molecular models from X-ray crystallography is a continuing problem. The refinement process as currently practiced is inherently biased through use of the model to provide phase information for the refinement process. To investigate the extent of model bias we are developing model-free criteria for detailed analysis of crystal structures. We present preliminary findings from comparing a set of high resolution, well-refined structures from the Joint Center for Structural Genomics repository to maps based solely on phases from selenomethionine anomalous scattering. Removal of atoms with little or no support in the "objective" map reliably improves or does not degrade the free R-factor. The selenomethionine map, or any other map produced without the assumption of a molecular model, can be used to identify features supported by diffraction data and those which come from the application of structural constraints.
Research at the NSF STC for Biology with X-ray lasers
Authors: Spence John 
Published: November 2015

The NSF BioXFEL Science and Technology Center (STC) is a new consortium of six research campuses devoted to the application of x-ray free-electron lasers (XFELs) to structural biology. Over the last four years a variety of approaches have been made to the observation of protein structure and dynamics for various classes of proteins. The Linac Coherent Light source at SLAC, the first hard-Xray EXFEL, provides intense coherent hard X-ray pulses at 120 Hz which vaporize protein when focussed to a sub-micron beam. Atomic-resolution Bragg diffraction patterns are nevertheless obtained using 50 fs pulses prior to the onset of significant damage, in this "diffract-then-destroy" mode, which outruns radiation damage. This use of short pulses instead of freezing samples to reduce radiation damage therefore opens the way to the study of protein dynamics at room temperature in a native environment. I'll review the work of several groups using a range of approaches to different types of sample, including the following: 1. Differences between the frozen sychrotron structure of GPCR proteins and the RT XFEL structure [1]. 2. Pump-probe dynamic structures in Photosynthesis [2]. 3. XFEL study of 2D protein crystals [3]. 4. Prospects for improved resolution in XFEL imaging from single particles such as viruses, where patterns can be obtained from a single virus. 5. New ideas - the Lipid Cubic Phase injector (which allows protein nanocrystals to be studied also at sychrotrons) [4], prospects for fast Laue diffraction using coherent attosecond X-ray lasers, ab-initio phasing [5], the use of angular correlation functions for analysis of fast solution scattering, and two-color opportunites for serial femtosecond crystallography (SFX). See [6] for a recent review of the field. 1. W.Liu et al Science 342, 1521 (2013) 2. A.Aquila et al Optics Express 20, 2706 (2012) 3. M.Frank et al IUCrJ (2014) In press. 4. U.Weierstall et al Nature Comms. (2014) In press. 5. J. Spence et al Optics Express 19, 2866 (2011). 6. J. Spence et al Rep. Prog. Phys. 75, 102601 (2012).
Structural modulations in multiferroic tetragonal tungsten bronze KxMnxFe1+xF3
Authors: Drathen Christina , Yusenko Kirill , Margadonna Serena 
Published: November 2015

Multiferroic materials showing coupling of the different order parameters (ferroelectric, ferromagnetic, ferroelastic) are interesting not only from a fundamental perspective, but also from a technological point of view, e.g. for to the development of new storage technologies. However, the coexistence of (ferro)magnetism and ferroelectricity is considered a rare phenomenon. Whilst this may be true for perovskite oxides, where emptyd-shells favor the off-centering of ions but counteract magnetism, this intrinsic limitation can be avoided by moving to different structure types, and/or away from oxides. An example of non-perovskite, non-oxide multiferroic systems are the tetragonal tungsten bronze (TTB) fluorides KxM2+xM3+1+xF3(x= 0.4 – 0.6), which show coexistence of electric and magnetic ordering 1. Here we present a detailed structural study on a series of TTB fluorides, KxMnxFe1+xF3(x = 0.4 – 0.55). KMnFeF6has been previously described as tetragonalP42bcand orders ferrimagnetically belowT = 148 K 2. Additional satellite reflections were found in transmission electron microscopy experiments and attributed to ferroelastic domains arising from tilting ofMF6octahedra, but the reported bulk powder XRD measurements indicated only tetragonal symmetry 3. We used high-resolution powder diffraction techniques to reinvestigate the crystal structure as a function of temperature in comparison with DSC data. Our results reveal a structural distortion to orthorhombic symmetry (Ccc2) at room temperature, which diminished when moving to the end members of the series (x → 0.4 andx → 0.6). Although structurally subtle, this distortion may indicate a ferroelectric state, similar to KxFeF3, where ferroelectricity is observed only in the orthorhombic phase. On heating, an anomaly in thec-axis lattice parameter accompanies a phase transition to centrosymmetricP42/mbcaround 320 – 350 K, marking the transition from ferroelectric – paraelectric state.
Significant risk factors associated with facilities management (FM) outsourcing
Authors: Ikediashi Dubem I. , Ogunlana Stephen O. 
Published: November 2015

Purpose
– The purpose of this paper is to extend the body of knowledge on healthcare facilities management (FM) by investigating the risks associated with outsourcing of FM services in hospitals.

Design/methodology/approach
– The paper relied on two strands of methodology common with pragmatic research. Questionnaire survey (QS) used data from 208 respondents representing ten hospitals while three out of the ten hospitals involved in the QS were selected based on their willingness to enter the case study (CS) interview. Data collected were analysed using descriptive and inferential statistics for QS and using narrative techniques by discussing themes, sub-themes for the CS.

Findings
– Findings established 24 out of the 35 risk factors as critical, four factors as somehow critical, and five factors as not critical. Besides, nine risk factors were found to be significantly loaded on the five risk categories. The rank analysis also revealed that the top five critical risk factors are: inexperience and lack of requisite skills; possibility of fraud by vendor; financial failure of chosen vendor; vendor opportunism; and fall in morale of employees.

Originality/value
– The study provides an unambiguous contribution to exiting body of knowledge on outsourcing risks as it relates to healthcare FM. It reinforces the theory that risks exist in any form of relationship but developed a distinct body of factors associated with outsourcing of FM services particularly from the context of Nigeria’s public healthcare sector.
Feature reduction with PCA/KPCA for gait classification with different assistive devices
Authors: Martins Maria , Santos Cristina , Costa Lino , Frizera Anselmo 
Published: November 2015

Purpose
– The purpose of this paper is to propose a gait analysis technique that aims to identify differences and similarities in gait performance between three different assistive devices (ADs).

Design/methodology/approach
– Two feature reduction techniques, linear principal component analysis (PCA) and nonlinear kernel-PCA (KPCA), are expanded to provide a comparison of the spatio-temporal, symmetrical indexes and postural control parameters among the three different ADs. Then, a multiclass support vector machine (MSVM) with different approaches is designed to evaluate the potential of PCA and KPCA to extract relevant gait features that can differentiate between ADs.

Findings
– Results demonstrated that symmetrical indexes and postural control parameters are better suited to provide useful information about the different gait patterns that total knee arthroplasty (TKA) patients present when walking with different ADs. The combination of KPCA and MSVM with discriminant functions (MSVM DF) resulted in a noticeably improved performance. Such combination demonstrated that, with symmetric indexes and postural control parameters, it is possible to extract with high-accuracy nonlinear gait features for automatic classification of gait patterns with ADs.

Originality/value
– The information obtained with the proposed technique could be used to identify benefits and limitations of ADs on the rehabilitation process and to evaluate the benefit of their use in TKA patients.
Decay rate performance approach for stabilization continuous fuzzy models using their discretized forms
Authors: Ellouze Ameni , Delmotte François , Lauber Jimmy , Chtourou Mohamed , Ksantini Mohamed 
Published: November 2015

Purpose
– The purpose of this paper is to deal with the stabilization of the continuous Takagi Sugeno (TS) fuzzy models using their discretized forms based on the decay rate performance approach.

Design/methodology/approach
– This approach is structured as follows: first, a discrete model is obtained from the discretization of the continuous TS fuzzy model. The discretized model is obtained from the Euler approximation method which is used for several orders. Second, based on the decay rate stabilization conditions, the gains of a non-PDC control law ensuring the stabilization of the discrete model are determined. Third by keeping the values of the gains, the authors determine the values of the performance criterion and the authors check by simulation the stability of the continuous TS fuzzy models through the zero order hold.

Findings
– The proposed idea lead to compare the performance continuous stability results with the literature. The comparison is, also, taken between the quadratic and non-quadratic cases.

Originality/value
– Therefore, the originality of this paper consists in the improvement of the continuous fuzzy models by using their discretized models. In this case, the effect of the discretization step on the performances of the continuous TS fuzzy models is studied. The usefulness of this approach is shown through two examples.
Negotiating a dominant heritage discourse. Sustainable urban planning in Cape Coast, Ghana
Authors: Fredholm Susanne 
Published: November 2015

Purpose
– With specific focus on sustainable development of the built environment in Cape Coast, Ghana, the purpose of this paper is to examine practical and conceptual barriers for local planning authorities advancing international outreach programmes based on a global discourse on heritage and heritage management.

Design/methodology/approach
– A discourse analysis was conducted on documents and programmes produced by international organisations and local planning authorities since 2000. Further qualitative data collection methods included 25 semi-structured interviews, literature and media review and on-site observations.

Findings
– The study shows that the dominant global discourse on heritage management being interconnected with tourism development is adopted by local planning authorities. However, the requirements to advance initiated urban redevelopment projects are neither adapted to the economic realities nor institutional capabilities of the local planning system. Instead of adjusting specific Ghanaian notions of heritage or local forms of heritage organisations, negotiating the discourse is potentially a more sustainable approach.

Practical implications
– The findings reveal important implications necessary to address from sustainable development perspective. The study can help practitioners to develop strategies based on local African planning contexts rather than western discourses on best practice.

Originality/value
– This study discusses the impact of an Authorised Heritage Discourse on local planning of the built environment, and the need to rescale and broaden the scope of such discourses to other levels than the dominating national/global.
Community involvement for sustainable heritage tourism: a conceptual model
Authors: Li Yulong , Hunter Caroline 
Published: November 2015

Purpose– The purpose of this paper is to explore why and how to involve community stakeholders to achieve sustainability in heritage tourism operations.Design/methodology/approach– A conceptual model and three propositions are created based on stakeholder theory and the social capital perspective.Findings– The study highlights the challenges facing heritage tourism operators and recommends that these organizations focus on inter-stakeholder group collaboration, participative decision making, responsibility and benefits sharing, and building an institutional power structure to involve hosting communities for sustainable operations.Practical implications– Instead of approaching from the traditional philosophic perspective at the overall societal level, community involvement is studied at individual organizational level to provide more specific recommendations on how tourism companies can empower and involve community stakeholders.Originality/value– This is one of the first studies to synthesize the constructs of organizational motivation, community empowerment, community involvement, and sustainable tourism operations in an integrated model to explore their relationships.
The influence of the Japanese tea ceremony on Japanese restaurant hospitality
Authors: Sato Yoshinobu , Parry Mark E. 
Published: November 2015

Purpose– Recent discussions of value-in-use from the perspective of service dominant logic have focused on the customer’s determination of value and control of the value creation process. The purpose of this paper is to extend these discussions by exploring the value creation process in the Japanese tea ceremony and in thekaiseki ryoristyle of Japanese cuisine, which is based on the Japanese tea ceremony.Design/methodology/approach– A historical analysis is used to describe the history of the Japanese tea ceremony in Japan and its influence on Japanese culture. key principles underlying the Japanese tea ceremony and their relationship to Zen Buddhism are summarized and the ways in which these principles are reflected in the service provided by Japanese restaurants are explored.Findings– The two elite restaurants examined in this analysis have designed their service experience to reflect four principles of the tea ceremony: the expression of seasonal feelings, the use of everyday items, ritualized social interactions, and the equality of host and guest. Given these principles, we argue that the tea ceremony and restaurants based on this ceremony imply a co-creation process that is different in three important ways from the process discussed in the co-creation literature. First, the tea ceremony involves dual experiential-value-creation processes. Both the master and the customer experience value-in-use during the delivery ofkaisekicuisine, and the value-in-use each receives is critically dependent on that received by the other. Second, the degree to which value-in-use is created for both parties (the customer and the master) depends on the master’s customization of the service experience based on his knowledge of the customer and that customer’s with the tea ceremony,kaiseki ryoricuisine and Japanese culture.Research limitations/implications– We hypothesize that the dual experiential-value-creation model is potentially relevant whenever the service process contains an element of artistic creation. Potential examples include concerts, recitals, theatre performances and art exhibitions, as well as more mundane situations in which the service provider derives value-in-use from aesthetic appreciations of the service provider’s art.Originality/value– Recent discussions of value co-creation argue that the customer controls the value creation process and the determination of value. The authors argue that the tea ceremony can serve as a metaphor for value co-creation in service contexts where the customer’s value creation process depends on the creation of value-in-use by the service provider.