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The search for superior production performance has been used by companies to overcome competition in the current global economic scenario. Efficient manufacturing connected to environmental initiatives provides a company with favourable conditions for maintaining uniform and continuous improvement in its competitive performance, while providing operational versatility to respond quickly to volatile markets. As production is one of the most expensive areas for a company, many organisations have sought a new management model for their production system that provides substantial productivity gains, cost saving opportunities and higher customer satisfaction. This study proposes a model of production management and an implementation method integrating the principles of lean manufacturing and sustainability, supported by cultural transformation at the company. Its objective was to achieve productivity gains and improvements on customer satisfaction, as well as develop the ability to provide quick responses to market changes in a globalised economy. The implementation of the proposed model should be gradual, initially addressing fundamental principles, and should operate simultaneously with, and in the same environment as, workforce development and organisational transformation initiatives, to create sustainable improvements.  相似文献   
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The photocatalytic activity and photostability of CdS quantum dot (QD) can be remarkably enhanced by hybridization with Rh‐substituted layered titanate nanosheet even at very low Rh substitution rate (<1%). Mesoporous CdS–Ti(5.2−x)/6Rhx/2O2 nanohybrids are synthesized by a self‐assembly of exfoliated Ti(5.2−x)/6Rhx/2O2 nanosheets with CdS QDs. The partial substitution of Rh3+/Rh4+ ions for Ti4+ ions in layered titanate is quite effective in enhancing an electronic coupling between hybridized CdS and titanate components via the formation of interband Rh 4d states. A crucial role of Rh substituent ion in the internal electron transfer is obviously evidenced from in situ X‐ray absorption spectroscopy showing the elongation of (Rh O) bond under visible light irradiation. This is the first spectroscopic evidence for the important role of substituent ion in the photoinduced electron transfer of hybrid‐type photocatalyst. The CdS–Ti(5.2−x)/6Rhx/2O2 nanohybrids show much higher photocatalytic activity for H2 production and better photostability than do CdS and unsubstituted CdS–TiO2 nanohybrid. This result is ascribable to the enhancement of visible light absorptivity, the depression of electron–hole recombination, and the enhanced hole curing of CdS upon Rh substitution. The present study underscores that the hybridization with composition‐controlled inorganic nanosheet provides a novel efficient methodology to optimize the photo‐related functionalities of semiconductor nanocrystal.  相似文献   
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Seo K  Varadwaj KS  Mohanty P  Lee S  Jo Y  Jung MH  Kim J  Kim B 《Nano letters》2007,7(5):1240-1245
We have observed unusual ferromagnetic properties in single-crystalline CoSi nanowire ensemble, in marked contrast to the diamagnetic CoSi in bulk. High-density freestanding CoSi nanowires with B20 crystal structure are synthesized by a vapor-transport-based method. The reaction of cobalt chloride precursor with a Si substrate produces high-aspect-ratio CoSi nanowires. The high-resolution transmission electron microscopy and electron diffraction studies reveal superlattice structure in CoSi nanowires with twice the lattice parameter of simple cubic CoSi lattice. The zero-field-cooled and field-cooled (ZFC-FC) measurements from the nanowire ensemble show freezing of the disordered surface spins at low temperatures. The magnetoresistance (MR) measurements of single nanowire devices show a negative MR whose magnitude gets larger at lower temperatures.  相似文献   
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