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51.
52.
This paper focuses on supply flexibility, i.e., the ability of the purchasing function to respond in a timely and cost effective manner to changing requirements of purchased components, in terms of volume, mix and delivery date. It is argued that managerial actions may have different effects on different dimensions of supply flexibility. More specifically, we aim to answer the following research questions: what is the effectiveness of the different supply flexibility sources? Are there any variables that could moderate the relationship between supply flexibility sources and supply flexibility? We perform a regression analysis of the effectiveness of the different supply flexibility sources. In particular, we conduct a stepwise regression, setting the supply flexibility sources as independent variables, and the three dimensions of supply flexibility (identified in the factor analysis) as dependent variables. In order to refine the models and increase the generalisability of the study, some control variables (i.e., firm revenue and flexibility focus) are also included in the regression analysis. Results suggest that each dimension of supply flexibility is associated with a particular group of sources, i.e., the sources used to increase a certain dimension of supply flexibility (e.g., supplier responsiveness) may be ineffective for another dimension (e.g., adaptability). 相似文献
53.
Jihyeon Gim Jinju Song Hyosun Park Jungwon Kang Kangkun Kim Vinod Mathew Jaekook Kim 《Nanoscale research letters》2012,7(1):60
The series of Li[Ni
x
M
x
Li1/3-x
Mn2/3-x
]O2 cathodes, where M is cobalt or chromium with a wide compositional range x from 0 to 0.33, were prepared by hydroxide coprecipitation method with subsequent quenching. The sample structures were investigated
using X-ray diffraction results which were indexed completely on the basis of a trigonal structure of space group with monoclinic C2/m phase as expected. The morphologies and electrochemical properties of the samples obtained were compared
as the value of x and substituted transition metal. The particle sizes of cobalt-substituted Li[Ni
x
Co
x
Li1/3-x
Mn2/3-x
]O2 samples are much smaller than those of the Li[Ni
x
Cr
x
Li1/3-x
Mn2/3-x
]O2 system. The electrode containing Li[Ni
x
Co
x
Li1/3-x
Mn2/3-x
]O2 with x = 0.10 delivered a discharge capacity of above 200 mAh/g after 10 cycles due to the activation of Li2MnO3. 相似文献
54.
Degradation of 32 emergent contaminants by UV and neutral photo-fenton in domestic wastewater effluent previously treated by activated sludge 总被引:1,自引:0,他引:1
De la Cruz N Giménez J Esplugas S Grandjean D de Alencastro LF Pulgarín C 《Water research》2012,46(6):1947-1957
This study focuses on the removal of 32 selected micropollutants (pharmaceuticals, corrosion inhibitors and biocides/pesticides) found in an effluent coming from a municipal wastewater treatment plant (MWTP) based on activated sludge. Dissolved organic matter was present, with an initial total organic carbon of 15.9 mg L−1, and a real global quantity of micropollutants of 29.5 μg L−1. The treatments tested on the micropollutants removal were: UV-light emitting at 254 nm (UV254) alone, dark Fenton (Fe2+,3+/H2O2) and photo-Fenton (Fe2+,3+/H2O2/light). Different irradiation sources were used for the photo-Fenton experiences: UV254 and simulated sunlight. Iron and H2O2 concentrations were also changed in photo-Fenton experiences in order to evaluate its influence on the degradation. All the experiments were developed at natural pH, near neutral. Photo-Fenton treatments employing UV254, 50 mg L−1 of H2O2, with and without adding iron (5 mg L−1 of Fe2+ added or 1.48 mg L−1 of total iron already present) gave the best results. Global percentages of micropollutants removal achieved were 98 and a 97% respectively, after 30 min of treatments. As the H2O2 concentration increased (10, 25 and 50 mg L−1), best degradations were observed. UV254, Fenton, and photo-Fenton under simulated sunlight gave less promising results with lower percentages of removal.The highlight of this paper is to point out the possibility of the micropollutants degradation in spite the presence of DOM in much higher concentrations. 相似文献
55.
The ability of Listeria monocytogenes and Escherichia coli O157:H7 inoculated by immersion (at 4.6 and 5.5 log CFU/ g, respectively) to survive on artichokes during various stages of preparation was determined. Peeling, cutting, and disinfecting operations (immersion in 50 ppm of a free chlorine solution at 4 degrees C for 5 min) reduced populations of L. monocytogenes and E. coli O157:H7 by only 1.6 and 0.8 log units, respectively. An organic acid rinse (0.02% citric acid and 0.2% ascorbic acid) was more effective than a tap water rinse in removing these pathogens. Given the possibility of both pathogens being present on artichokes at the packaging stage, their behavior during the storage of minimally processed artichokes was investigated. For this purpose, batches of artichokes inoculated with L. monocytogenes or E. coli O157:H7 (at 5.5 and 5.2 log CFU/g, respectively) were packaged in P-Plus film bags and stored at 4 degrees C for 16 days. During this period, the equilibrium atmosphere composition and natural background microflora (mesophiles, psychrotrophs, anaerobes, and fecal coliforms) were also analyzed. For the two studied pathogens, the inoculum did not have any effect on the final atmospheric composition (10% O2, 13% CO2) or on the survival of the natural background microflora of the artichokes. L. monocytogenes was able to survive during the entire storage period in the inoculated batches, while the E. coli O157:H7 level increased by 1.5 log units in the inoculated batch during the storage period. The modified atmosphere was unable to control the behavior of either pathogen. 相似文献
56.
Gastón Ares Ana Giménez Adriana Gámbaro 《Journal of the science of food and agriculture》2008,88(12):2061-2068
BACKGROUND: The aims of the present study were to study the influence of information about the source of two functional ingredients (antioxidants and fibre) on consumer perception of functional milk dessert concepts and to evaluate whether this influence depends on consumer attitudes towards health and hedonic characteristics of foods. RESULTS: Scores for expected liking decreased when information about the source of fibre or antioxidants was incorporated, which could be explained considering that when consumers knew the source of the functional ingredient they imagine the flavour of the source in the milk concept. This decrease in expected liking led to a decrease in consumer willingness to purchase, showing the importance of hedonic expectations on the acceptance of functional foods. Consumers with different attitudes towards health and hedonic characteristics of foods reacted differently towards information about the source of functional ingredients. CONCLUSION: Providing information about the source of functional ingredients would not be recommended as it might create negative taste expectations to consumers and a concomitant decrease in their willingness to purchase. These show that consumers would not compromise on the taste of milk desserts for health. Thus, the development of functional foods that taste worse than conventional ones may be a risky option. Copyright © 2008 Society of Chemical Industry 相似文献
57.
Seungo Gim Illhwan Lee Jae Yong Park Jong‐Lam Lee 《Small (Weinheim an der Bergstrasse, Germany)》2017,13(23)
A flexible hazy substrate (FHS) with embedded air bubbles to increase light extraction efficiency of organic light‐emitting diodes (OLEDs) is reported. In order to embed the air bubbles in the flexible substrate, micropatterned substrates are fabricated by plasma treatment, and then coated with a planarization layer. During the planarization layer coating, air bubbles are trapped between the substrate and the planarization layer. The haze of the FHS can be controlled from 1.7% to 68.4% by changing the size of micropatterns by adjusting the plasma treatment time. The FHS shows average haze of 68.4%, average total transmittance of 90.3%, and extremely flat surface with average roughness (R a) of 1.2 nm. Rigorous coupled‐wave analysis and finite‐difference time‐domain simulations are conducted to demonstrate that the air bubbles in the substrate can effectively extract photons that are trapped in the substrate. The FHS increases the power efficiency of OLEDs by 22% and further increases by 91% combined with an external extraction layer. Moreover, the FHS has excellent mechanical flexibility. No defect has been observed after 10 000 bending cycles at bending radius of 4 mm. 相似文献
58.
Almudena Giménez Soraya Bordoy Auxiliadora Sánchez Miguel López-Zamora Josep M. Sopena Juan L. Luque 《Journal of Computer Assisted Learning》2021,37(2):510-520
Difficulties in implementing effective instruction for at-risk students arise from two challenges: the transfer of evidence-based knowledge and the lack of economic resources. Computer-assisted programmes offer a suitable solution, providing quality instruction using low-cost resources. Thirty-two first-grade students with early learning difficulties were identified and paired based on at least three of the pre-intervention reading measures (reading efficiency of monosyllabic and disyllabic items, words, pseudowords and text reading speed). Each pair was assigned to one of two different intervention programmes: a computer-assisted intervention programme (CAIP) focused on syllables or the programme provided by the Spanish State School Assistance Services (SSAS). Every week, the CAIP participants received in pairs four 15-min training sessions on syllable decoding plus one 30-min group comprehension session. The CAIP was delivered by trainee students. The SSAS programme typically consisted of a 1-hr individual or in small groups sessions per week delivered by trained practitioners. Both programmes were administered for 11 weeks. The CAIP intervention showed better results than the SSAS intervention for both decoding and comprehension, with moderate to large effect sizes. 相似文献
59.
Tae-Hyoung Tommy Gim 《Papers in Regional Science》2021,100(4):1055-1077
This study conceptually confirms and empirically tests the potential that the significance and magnitude of the compact land use–trip time relationship differ by the degree of compactness and trip time. Based on a quantile regression of about 25,000 commuters in Seoul, Korea, the empirical analysis suggests a significant level for each neighbourhood land use variable and a magnitude change within the level. Weekend trip and school densities are significant for shorter trip time commuters, population density is significant for longer trip time commuters, and pedestrian density is significant for all commuters. Wherever significant, the land use variables exert stronger effects as their values increase. 相似文献
60.
Ileana de los A. Gremasqui Maria A. Giménez Manuel O. Lobo Norma C. Sammán 《International Journal of Food Science & Technology》2021,56(12):6507-6514
The objective was to study the nutritional and functional properties of hydrolysates from quinoa (Chenopodium quinoa) obtained by enzymatic hydrolysis of defatted quinoa flour (DQF). The commercial enzymes alcalase and flavourzyme were used to obtain the hydrolysates defatted quinoa flour hydrolysate with alcalase (DQFA) and defatted quinoa flour hydrolysate with flavourzyme (DQFF), respectively, after 3 h of digestion at 50°C and pH 8. The degree of hydrolysis (47.32%), yield (31.05%) and protein recovery (88.80%) values were higher in DQFA; however, its protein content (48.34%) was lower compared to that of DQFF (55.06%). Also, DQFA had a solubility greater than 57% over a wide pH range (2–10) and good foam stability (70–90%). On the other hand, DQFF presented adequate emulsifying activity (61.30 m2/g), emulsifying stability (158.62 min) and foaming capacity (131%). Due to the high content of macro- and micronutrients and adequate emulsifying and foaming properties, DQFA and DQFF could be used as ingredients in various processed food products and protein supplements. 相似文献