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991.
A new method is presented for determining thecis/trans isomer content of edible vegetable oils. The intensities of Raman lines near 1656 and 1670 cm−1 are associated with thecis andtrans configuration, respectively. A precision of ca. 1% can be obtained in thecis/trans isomer analysis of binary mixtures of methyl esters and triglycerides of monoenes and dienes and of hydrogenated vegetable oils. The spectroscopic data also provide the iodine value of vegetable oils or isolated fractions with precision for a single determination of ca. 1%. Presented at the AOCS meeting, Houston, May 1971. W. Market. Nutr. Res. Div., ARS, USDA.  相似文献   
992.
Robert Pietrzak 《Carbon》2007,45(13):2537-2546
Highly porous wood-based activated carbon was treated with species extracted from the surface of pyrolyzed sewage sludge. Their deposition on the external surface was visible by a change of the color of the carbon and on internal surfaces, by a decrease in porosity. The as-received carbon and its impregnated counterpart were heat treated at 950 °C at an inert atmosphere. Data for the adsorption on NO2 was carried out from dry and moist (70% humidity) air. The results indicated that for all materials a significant amount of NO2 was reduced to NO and released from the system. Heat treatment increases the capacity possibly as a result of an increase in basicity. The addition of the inorganic phase has a positive effect only when adsorption is run in moist conditions and inorganic nitrates and nitrites were formed. Otherwise, the NO2 adsorbed and nitric and nitrous acids formed on the surface significantly increase the acidity of the carbons by the formation of oxygen-containing groups and organic nitrates.  相似文献   
993.
Constraint-based modeling is largely used in computational studies of metabolism. We propose here a novel approach that aims to identify ensembles of flux distributions that comply with one or more target phenotype(s). The methodology has been tested on a small-scale model of yeast energy metabolism. The target phenotypes describe the differential pattern of ethanol production and O2 consumption observed in “Crabtree-positive” and “Crabtree-negative” yeasts in changing environment (i.e., when the upper limit of glucose uptake is varied). The ensembles were obtained either by selection among sampled flux distributions or by means of a search heuristic (genetic algorithm). The former approach provided indication about the probability to observe a given phenotype, but the resulting ensembles could not be unambiguously partitioned into “Crabtree-positive” and “Crabtree-negative” clusters. On the contrary well-separated clusters were obtained with the latter method. The cluster analysis further allowed identification of distinct groups within each target phenotype. The method may thus prove useful in characterizing the design principles underlying metabolic plasticity arising from evolving physio-pathological or developmental constraints.  相似文献   
994.
Over the last 20 years many new species of N2-fixing bacteria have been discovered in association with grasses, cereals and other non-nodulating crops. Virtually all of these bacteria are microaerophylic, fixing N2 only in the presence of low partial pressures of oxygen. Until a few years ago much attention was focussed on members the genusAzospirillum and it was assumed that N2 fixation was restricted to the rhizosphere or rhizoplane of the host plants. Through the use of N balance and15N techniques it has been shown that in the case of lowland rice, several tropical pasture grasses and especially sugar cane, the contributions of biological N2 fixation (BNF) are of agronomic significance.More detailed study of the N2-fixing bacteria associated with sugar cane (Acetobacter diazotrophicus andHerbaspirillum spp.) has shown that they occur in high numbers not only in roots of this crop but also in the stems, leaves and trash but are rarely found in the soil. Some of these endophytic diazotrophs have now also been found in forage grasses, cereals, sweet potato and cassava, although evidence of significant BNF contributions is still lacking.The identification of these endophytic diazotrophs as the organisms probably responsible for the high contributions of N2 fixation observed in sugar cane suggests that it may be possible to attain significant BNF contributions in some other gramineae and perhaps root crops.  相似文献   
995.
Niobium pentoxide (T form, orthorhombic system) was utilized to promote devitrification in Li2O · Al2O3· 6SiO2 glasses. Two or more mole percentage of this nucleating dopant enhanced crystallization in these glasses. Glasses containing 4.0 and 8.0 mol% T-Nb2O5 exhibited a high tendency to form dispersed TT-Nb2O5 (monoclinic system) precipitates during the glass quenching process. The crystallization process in glasses containing 2.0 or 4.0 mol% T-Nb2O5 occurred as microphase separation, followed by the formation of dispersed TT-Nb2O5 crystalline precipitates (760°C), followed by β-quartz solid-solution ( ss ) formation (850° to 900°C) heterogeneously nucleated from the precipitates. β-quartz( ss ) transformed to β-spodumene( ss ), along with a polymorphic transition from the TT-Nb2O5 to M-Nb2O5 (tetragonal system) crystalline phase.  相似文献   
996.
Technology readiness (TR) represents an individual’s mental readiness to accept new technologies. Although the TR scale has been used in many studies, its application in the healthcare context is limited. This paper focuses on identifying the TR profiles of medical staff and to model preference TR variations with respect to computer use, computer knowledge and computer feature demands. The study reports results from a nationwide study conducted in Greece, during a three-year period, which sampled responses from 604 physicians and nurses working in 14 Greek hospitals. Exploratory Structural Equation Modelling analysis is used in order to confirm the structure of the Technology Readiness Index. The results confirm the five groups of the TR taxonomy. Statistical differences were found between classes in information and communication technology (ICT) knowledge, ICT feature demands, hours of use per week as well as ICT use performance, but not in the general use of ICT. The results facilitate comprehension of the factors, which influence the use of ICT by medical staff and, in addition, they convey important policy and managerial implications. In conclusion, medical staff should be treated according to its TR taxonomy classes in order to expedite the acceptance and use of an ICT system.  相似文献   
997.
Although enterprise systems (ES) are ubiquitous, many firms report less than stellar payoffs from these costly investments, with underutilization often attributed to failures in the implementation process. Unfortunately, research has not provided sufficient insights into these failures, in part because it has focused on actual usage, as opposed to proficient usage, as the benchmark for successful implementation. Moreover, research has not generally examined how the adoption process unfolds over time, thus overlooking potential underlying mechanisms that may help explain how adopters achieve proficiency. To begin addressing these shortcomings, we study how adopters’ pre-adoption expectations, enacted over time, can influence their post-adoption proficiency, by shaping how and why they spend time using the system during the adoption period. We analyzed time-lagged survey data from 153 financial analysts, required to adopt new ES-based software, at a multinational bank. We found that adopters who hold pre-adoption expectations reflecting greater internal and external motives to adopt the system as well as systematically integrate it into their work routines are more apt to use the system in ways that enhance their cumulative knowledge of it, and subsequently develop higher levels of proficiency post-adoption. Moreover, greater organizational support enhanced the impact of adopters’ expectations on proficiency, except when their actual use is low in which case organizational support had an adverse effect.  相似文献   
998.
This study investigates the relationship between personality factors, cultural practices, and innovativeness on the national level. Hitherto no study has been done which considers these factors simultaneously. We argue that the relationship between national aggregated personality factors and the level of national innovation is mediated by national cultural practices. Our model is based on three arguments: First, Five Factor theory and cultural theory state that the national personality profile of a country influences its cultural practices. Second, person‐environment‐fit theory argues that personality factors can best manifest themselves in an appropriate environment. Third, in contrast to the individual level, we argue that on the national level cultural practices may not act as a moderator but as a mediator. Based on the triangulation of three datasets, we subsequently test our model on a sample of N = 33 countries. Our results demonstrate that innovation‐relevant national personality profiles are closely linked with innovation‐relevant national cultural practices. Further, we show that national cultural practices mediate the relationship between national personality profiles and national innovativeness. Additionally, we reveal that the recently proposed relationship between nationally aggregated personality profiles and national innovativeness virtually disappears as soon as national cultural practices are integrated into the model.  相似文献   
999.
The business value of information technology (IT) has been one of the top concerns of both practitioners and scholars for decades. Numerous studies have documented the positive effects of IT capability on organizational performance but our knowledge of the processes through which such gains are achieved remains limited due to a lack of focus on the business environment. Such a linkage therefore remains the subject of debate in the information systems literature. In this study, we fill this gap by investigating the mediating role of business process agility and the moderating roles of environmental factors. On the basis of matched survey data obtained from 214 IT and business executives from manufacturing firms in China, our analyses show that even though firm-wide IT capability presents the characteristics of rarity, appropriability, non-reproducibility, and non-substitutability, its impact on organizational performance is fully mediated by business process agility. Our results also show that the impact of the environment is multifaceted and nuanced. In particular, environmental hostility weakens the effect of IT capability on business process agility, while environmental complexity strengthens it. The theoretical and practical implications of this study, and its limitations, are also discussed.  相似文献   
1000.
Clinical pathway is an approach to standardise care processes to support the implementations of clinical guidelines and protocols. It is designed to support the management of treatment processes including clinical and non-clinical activities, resources and also financial aspects. It provides detailed guidance for each stage in the management of a patient with the aim of improving the continuity and coordination of care across different disciplines and sectors. However, in the practical treatment process, the lack of knowledge sharing and information accuracy of paper-based clinical pathways burden health-care staff with a large amount of paper work. This will often result in medical errors, inefficient treatment process and thus poor quality medical services. This paper first presents a theoretical underpinning and a co-design research methodology for integrated pathway management by drawing input from organisational semiotics. An approach to integrated clinical pathway management is then proposed, which aims to embed pathway knowledge into treatment processes and existing hospital information systems. The capability of this approach has been demonstrated through the case study in one of the largest hospitals in China. The outcome reveals that medical quality can be improved significantly by the classified clinical pathway knowledge and seamless integration with hospital information systems.  相似文献   
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