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JPC – Journal of Planar Chromatography – Modern TLC - The lipophilicity of 2,6-disubstituted 7-methylpurines and 6-mer-captopurine has been determined by reversed-phase thin-layer...  相似文献   
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JPC – Journal of Planar Chromatography – Modern TLC - Carbohydrates have been examined by TLC on layers modified with metal ions, in the form of salts, by dipping commercial plates in...  相似文献   
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There is no formalised approach for problem structuring and quantitative decision support to operationalise corporate social responsibility (CSR) implementation. In this paper, techniques for considering criteria relationships are outlined and a holistic, systematic framework combining a qualitative and quantitative method for practical CSR integration is provided. Cognitive mapping (CM) is applied to structure the problem picture, and the cause–effect relationships between decision elements. Soft CM methodology is employed to assess the cross-criteria interactions, at both an individual and a collective level. The interactions of criteria can have a significant impact upon CSR implementation. Such impacts can be direct or indirect through their close linkages to other criteria. The causal strategic map serves as an input to the analytic network process (ANP) to carry out the multi-criteria decision analysis. Then, CM and ANP are applied in a comparative analysis to verify whether the measures of criteria significance do correspond. The key criteria in networks are identified using centrality in CM and single limited priorities in ANP. This study demonstrates that using criteria without considering their interactions will result in shortcomings in the evaluation and assessment of CSR programmes. The holistic framework, combining CM and ANP proposed in this work, enhances the process of problem structuring and supports preference-based evaluation of decision alternatives. The results of our study yield that the mapping procedure has an influence on the criteria significance in networks. The correspondence between CM and ANP is stronger when cause relationships are rigidly interpreted. More unambiguous interpretations of causal relations can be achieved if methods are used jointly and common peaks of importance in both CM and ANP could potentially serve as indications of key decision elements.  相似文献   
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The structure-based design, synthesis and activity prediction of new leucine aminopeptidase inhibitors, the phosphonamidate and phosphinate dipeptide analogues are presented.  相似文献   
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Integration of corporate social responsibility (CSR) into a company’s mainstream strategy is a complex task. Practical implementation of CSR requires analysis of both the external and internal environments to determine the prospects and challenges significantly influencing integration of sustainability into business strategy. In order to overcome limitations of single multiple-criteria decision analysis models, this paper proposes a hybrid integrated framework combining cognitive mapping and analytic networks process (ANP) to determine, prioritise and select CSR programmes for implementation. The strategic cognitive map serves as a foundation to build the ANP network and identify the importance of CSR programmes. A knapsack optimisation method is then used to optimally assign resources to CSR alternatives. We demonstrate the usefulness of the framework through a case study in the extractive sector. The framework was empirically tested with 61 respondents using postal and online surveys, MBA workshops, and conference networking.  相似文献   
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Single‐component self‐assembled monolayers (SAMs) of mercaptoethanesulfonate (MES) on Ag surfaces were studied with surface‐enhanced resonance Raman scattering (SERRS) spectroscopy with a view to their application to immobilize (ferro)cytochrome c (cyt c). SERS studies revealed that MES molecules adopt primarily trans (T) conformation even at early stages of the SAM growth and over wide range of pH values. High accessibility of the negatively charged groups for (bio)molecules in solution makes single‐component MES SAMs suitable linkage monolayers for electrostatic attachment of cyt c, which was verified with SERRS. Cyt c was successfully anchored to MES‐coated Ag at natural (∼5), neutral, and isoelectric point (10.6) pH. At pH = 7.0 and 10.6, SERRS bands characteristic of native six‐coordinated low‐spin (6cLS) heme iron configuration were detected. Lack of buffering resulted in additional appearance of five‐coordinated high‐spin (5cHS) SERRS markers and the presence of bands indicating ferric ion. An electrostatic attraction between protein and SAM was confirmed to exclude the hydrophobic interactions involved in cyt c binding. Cyt c attached to MES SAM on Ag was found to be electroactive at neutral pH, and protein oxidation was assisted with reversible conversion of 6cLS to the non‐native 5cHS state. Alteration of heme orientation deduced from SERRS spectra upon change of redox state allowed us to propose the protein dynamics as the electron transfer rate‐limiting step. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
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