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1.
ABSTRACTWith a greater number of B2B firms integrating customers into the new product development (NPD) process, how to utilize customer involvement in NPD is an important decision because it may be a double-edged sword carrying both bright and dark sides. Utilizing a sample of 193 B2B firms across various industries, we validate previous research that suggests market orientation positively influences NPD performance and subsequently examine how this relationship may either be enhanced or diminished contingent upon how customers are utilized in the NPD process. The results show that the market orientation–NPD performance relationship is enhanced by having customers participate in a greater number of activities throughout NPD (customer participation breadth) and diminished when customers are involved at deeper levels (customer participation depth). This research suggests that the exact involvement of customers is a critical decision and has clear implications for the dialogues about customer involvement and management of customer relationships. 相似文献
2.
A series of 16-layer polypropylene/flame retardant (PP/FR) film/foam composite structures were produced by microlayer coextrusion. A highly branched PP was used in the foam layers to increase strain hardening and cell stability, while the PP used in the film layers was a high shear viscosity grade to confine bubble growth. In addition to improved tensile properties, the PP/FR composite film/foams exhibited five times the compression modulus of PP/FR composite foams at each FR loading level. The thermal stabilities of the composites were investigated, exhibiting three step decompositions. The FR particles were effective in decreasing flammability by forming intumescent char. The PP/FR-film/foam-20 showed self-extinguishing behavior in a modified vertical burn test, while the PP/FR-foam-20 sample continued to burn. Cone calorimetry demonstrated that PP/FR film/foams had lower heat release than PP/FR foams due to the unique alternating film/foam structure of PP/FR film/foams. Scanning electron microscopy imaging of the residual chars from fire testing that the PP/FR composite film/foams showed a more continuous protective char surface when compared with PP/FR composite foams at each FR concentration. The combined data indicate that the formation of a surface film on top of a foam ensures a robust intumescent fire protective barrier for partly foamed materials and shows a new way toward lightweight materials with improved fire safety performance. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48552. 相似文献
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Water Resources Management - With many countries facing water scarcity and the demand for water ever-increasing, more people are turning to rainwater harvesting (RWH) as a feasible way of... 相似文献
4.
Journal of Materials Science - For decades, a wide variety of products have benefitted from the use of flexible PVC, ranging from healthcare to cable to packaging & household items. The... 相似文献
5.
Morgan Mercredi Trevor J. Vincent Christopher P. Bidinosti Melanie Martin 《Magma (New York, N.Y.)》2017,30(1):1-14
Objective
Current magnetic resonance imaging (MRI) axon diameter measurements rely on the pulsed gradient spin-echo sequence, which is unable to provide diffusion times short enough to measure small axon diameters. This study combines the AxCaliber axon diameter fitting method with data generated from Monte Carlo simulations of oscillating gradient spin-echo sequences (OGSE) to infer micron-sized axon diameters, in order to determine the feasibility of using MRI to infer smaller axon diameters in brain tissue.Materials and methods
Monte Carlo computer simulation data were synthesized from tissue geometries of cylinders of different diameters using a range of gradient frequencies in the cosine OGSE sequence . Data were fitted to the AxCaliber method modified to allow the new pulse sequence. Intra- and extra-axonal water were studied separately and together.Results
The simulations revealed the extra-axonal model to be problematic. Rather than change the model, we found that restricting the range of gradient frequencies such that the measured apparent diffusion coefficient was constant over that range resulted in more accurate fitted diameters. Thus a careful selection of frequency ranges is needed for the AxCaliber method to correctly model extra-axonal water, or adaptations to the method are needed. This restriction helped reduce the necessary gradient strengths for measurements that could be performed with parameters feasible for a Bruker BG6 gradient set. For these experiments, the simulations inferred diameters as small as 0.5 μm on square-packed and randomly packed cylinders. The accuracy of the inferred diameters was found to be dependent on the signal-to-noise ratio (SNR), with smaller diameters more affected by noise, although all diameter distributions were distinguishable from one another for all SNRs tested.Conclusion
The results of this study indicate the feasibility of using MRI with OGSE on preclinical scanners to infer small axon diameters.6.
Jemish Parmar Xing Ma Jaideep Katuri Juliane Simmchen Morgan M Stanton Carolina Trichet-Paredes Lluís Soler Samuel Sanchez 《Science and Technology of Advanced Materials》2015,16(1)
Self-propelled micromotors are emerging as important tools that help us understand the fundamentals of motion at the microscale and the nanoscale. Development of the motors for various biomedical and environmental applications is being pursued. Multiple fabrication methods can be used to construct the geometries of different sizes of motors. Here, we present an overview of appropriate methods of fabrication according to both size and shape requirements and the concept of guiding the catalytic motors within the confines of wall. Micromotors have also been incorporated with biological systems for a new type of fabrication method for bioinspired hybrid motors using three-dimensional (3D) printing technology. The 3D printed hybrid and bioinspired motors can be propelled by using ultrasound or live cells, offering a more biocompatible approach when compared to traditional catalytic motors. 相似文献
7.
Apparatus for the vertical orientation cone calorimeter testing of flexible polyurethane foams 下载免费PDF全文
Of concern to regulators and fire safety engineers is how flexible polyurethane foam drips and flows during burning. Specifically, flexible polyurethane foam forms a burning ‘pool’ of liquid as the foam decomposes, which can lead to accelerated flashover events. To fully study this phenomenon where the ‘pool fire’ accelerates heat release, large‐scale tests like the furniture calorimeter (American Society of Testing and Materials (ASTM) E1537) are used, and no small‐scale technique exists. In this paper, we present our work in developing a new sample holder that works with a bench‐scale heat release test, the cone calorimeter (ASTM E1354). The holder was built upon designs developed by the National Institute of Standards and Technology, which placed the foam in a cage in a vertical orientation during cone calorimeter testing. In this paper, we show the schematics for this test apparatus, as well as results obtained with this apparatus on four different flexible foams (shape memory and high‐density foam, flame retarded and non‐flame retarded). We compare the results from the vertical testing with that obtained via traditional horizontal ASTM E1354 testing. The advantages and disadvantages of this new apparatus are discussed in this paper. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
8.
We consider a Fermion in the presence of a rotating BH immersed in a universe with a positive cosmological constant. After presenting a rigorous classification of the number and type of the horizons, we adopt the Carter tetrad to separate the aforementioned equation into radial and angular equations. We show how the Chandrasekhar ansatz leads to the construction of a symmetry operator that in the limit of a vanishing cosmological constant reproduces the square root of the squared total angular momentum operator for a Dirac particle in the Kerr metric. Furthermore, we prove that the the spectrum of the angular operator is discrete and consists of simple eigenvalues, and by means of the functional Bethe ansatz method we also derive a set of necessary and sufficient conditions for the angular operator to have polynomial solutions. Finally, we show that there exist no bound states for the Dirac equation in the non-extreme case. 相似文献
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