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991.
The proliferation of the Internet has given birth to a number of complaint web sites where dissatisfied and frustrated consumers can easily articulate their opinions and comments on products, services, or companies. Little attention, however, has been paid to the influence of online complaints on potential consumers’ behaviors. This study attempts to provide the understanding of causal attribution process in the online complaining behaviors. The results showed that informational factors, such as vividness and consensus, facilitated consumers’ attribution to companies’ responsibility for the negative events, and subsequently led to changing their evaluation of the companies. In addition, we found that corporate response strategies to online complaints should be different from the conventional response strategies. 相似文献
992.
Rocío Sánchez-Mangas Antonio García-Ferrrer Aranzazu de Juan Antonio Martín Arroyo 《Accident; analysis and prevention》2010,42(4):1048-1056
The number of deaths in road traffic accidents in Spain exceeds three thousand people each year. Public authorities have implemented some policies with the aim to reducing this number. Among them, the improvement of road quality standards and some legal changes encouraging careful driving behavior. However, less attention has been focused on one of the issues that may be critical to reducing the number of fatalities caused by traffic accidents: a quick emergency medical care. In this paper, we use a sample of more than 1400 accidents occurred on Spanish roads in May 2004. Our objective is to analyze to which extent a reduction of the time interval between the crash and the arrival of the emergency services to the crash scene is related to a lower probability of death. Our results suggest that a 10 min reduction of the medical response time can be statistically associated with an average decrease of the probability of death by one third, both on motorways and conventional roads. 相似文献
993.
Abstract The delignification response in cooking and the impact of bleaching on earlywood and latewood were studied. Spruce earlywood and latewood chips were pulped by the kraft process and subsequently treated with one bleaching chemical at a time. In cooking, latewood required a higher alkali charge to reach the same kappa number. No difference in the light absorption coefficient between the different fiber types was observed. After oxygen delignification the earlywood fibers had a higher light absorption coefficient at the same kappa number. The difference in light absorbing material was maintained when bleaching was performed with chlorine dioxide, ozone, and peracetic acid. Hydrogen peroxide decreased the light absorbing structures in the earlywood to the same level as for latewood. The earlywood pulp had a higher brightness at a given kappa number than the latewood. The higher brightness remained through all bleaching operations and was primarily due to a higher light scattering ability. 相似文献
994.
从建筑结构模型的阻尼值出发,探讨了阻尼对反应听谱的影响,对几种特殊结构的阻尼进行了分析,因此,设计中应结合结构体系材料选取合适的阻尼比数值。 相似文献
995.
Qing Xu Di Zhan Han-Xing Liu Wen Chen Duan-Ping Huang Feng Zhang 《Acta Materialia》2013,61(12):4481-4489
BaZrxTi1?xO3 (x = 0.2, 0.25, 0.3) ceramics were prepared by a citrate method. The ferroelectric phase transition behavior and bias electric-field-induced dielectric nonlinearity of the ceramics were investigated. With increasing zirconium content, the phase transition behavior of the ceramics changed from a diffusion phase transition to relaxor-like behavior. Applying bias electric field in diverse manners led to differing effects on the dielectric nonlinearity, depending on the zirconium content of the ceramics. These dielectric phenomena were related to the polarization response of polar nano-regions (PNRs) embedded in the ceramics, which are macroscopically in the paraelectric state at room temperature. The characteristic parameters of PNRs were determined by fitting the dielectric constants under bias electric field to a multipolarization mechanism model. It was found that the size of PNRs was decreased with increasing zirconium content. The evolution of the phase transition behavior and dielectric nonlinearity with zirconium content was interpreted in relation to the size change of PNRs. 相似文献
996.
该文介绍比例伺服传动技术上的一款具有突破性的产品,DF plus比例阀.该产品采用了全新专利的阀芯驱动技术——音圈驱动技术VCD(Voice Coil Drive),使该阀具有伺服阀的动态特性,比例阀的可靠耐用等优点,在最大流量下该阀仍具有极好的动态特性,适用于高精度的液压传动系统的压力,速度和位置控制. 相似文献
997.
998.
Nylon-polystyrene microcapsules with immobilized ferroelectric liquid crystalline segments were prepared, and the permeability control of the encapsulated core material was investigated under an external electric field. A ferroelectric liquid crystal monomer possessing both mesogenicity and chirality effectively responded to an external electrical field. Permeation of the material (oxprenolol) contained in the inner aqueous core of the microcapsules was enhanced under a feeble electric field (2 V). Furthermore, it was found that the permeability of the microcapsules without the ferroelectric liquid crystal group did not depend on the external electrical field. In order to clarify the controlled release mechanism of the core material, the transmittance was quantitatively evaluated under an external electric field using a handmade polarized light transmittance apparatus. 相似文献
999.
The effects of butadiene/styrene ratio, monomer distribution, and molecular weight distribution and branching on the pressure sensitive adhesive properties of butadiene/ styrene radial teleblock copolymers are reported. Styrene content of polymers with varying structures shows a close relation with tack response, and styrene content and structure affect solution viscosity and shear adhesion. When part of the styrene is incorporated into the polybutadiene segment to yield a block progressively enriched in styrene (tapered block), solution viscosity and shear adhesion are reduced. When the butadiene segment is replaced by a block of randomly copolymerized butadiene and styrene, the polymers provide lower solution viscosities and shear adhesion but unchanged tack. The molecular weight distribution of the radial teleblock polymers can vary from broad, highly branched compositions to narrow molecular weight distributions of almost Iinear polymers. The latter have relatively high solution viscosity and low shear adhesion, whereas the former polymers produce moderate solution viscosity but high shear adhesion. Tack is generally unaffected. 相似文献
1000.
WANG ShanShan & REN QingWen College of Mechanics Materials Hohai University Nanjing China 《中国科学:信息科学(英文版)》2011,(3)
Gravity dam is a typical structure that has been frequently used in the fields of water conservancy engineering, and the safety of the structure has received widespread attention recently. Due to earthquakes or other reasons, gravity dams normally have damage such as cracks in practical service. Damage in the structures can alter the structural dynamic behavior and seriously affect structural performance. Maintaining safety and integrity of the gravity dam structures requires a better understanding of dynam... 相似文献