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61.
InP films have been grown by close space transport employing 0.8 mol% PCl3 in H2. For deposition on InP single crystals, 700C source and 650C substrate temperatures produced epitaxial films on (100), polycrystalline films on (111)A, and powdery layers on (111)B. Growth rates are 6 to 10 |Gmm/hr on (100) InP and ~50 μm/hr on (111)A InP. Regardless of InP source doping, deposits exhibit net donor concentrations of 5×1017 to 1×1018cm?3. Zn doping with 0.02 to 0.5 mol% Zn(C2H5)2 in the gas phase resulted in partially compensated p-InP with net acceptor concentrations up to 7×1018cm?3. Polycrystalline films have been grown on Mg-coated carbon or molybdenum substrates at 700C source and 590C substrate temperatures. Growth rates lie between 40 and 50 μm/hr. Substantial recrystallization and grain growth are observed after 2 day anneals at 950C under 5 atm of phosphorus. 相似文献
62.
Haker Steven Zhu Lei Tannenbaum Allen Angenent Sigurd 《International Journal of Computer Vision》2004,60(3):225-240
Image registration is the process of establishing a common geometric reference frame between two or more image data sets possibly taken at different times. In this paper we present a method for computing elastic registration and warping maps based on the Monge–Kantorovich theory of optimal mass transport. This mass transport method has a number of important characteristics. First, it is parameter free. Moreover, it utilizes all of the grayscale data in both images, places the two images on equal footing and is symmetrical: the optimal mapping from image A to image B being the inverse of the optimal mapping from B to A. The method does not require that landmarks be specified, and the minimizer of the distance functional involved is unique; there are no other local minimizers. Finally, optimal transport naturally takes into account changes in density that result from changes in area or volume. Although the optimal transport method is certainly not appropriate for all registration and warping problems, this mass preservation property makes the Monge–Kantorovich approach quite useful for an interesting class of warping problems, as we show in this paper. Our method for finding the registration mapping is based on a partial differential equation approach to the minimization of the L
2 Kantorovich–Wasserstein or Earth Mover's Distance under a mass preservation constraint. We show how this approach leads to practical algorithms, and demonstrate our method with a number of examples, including those from the medical field. We also extend this method to take into account changes in intensity, and show that it is well suited for applications such as image morphing. 相似文献
63.
Iodine value (IV) limitation of biodiesel is currently one of the most discussed topics within the different world‐wide biofuel specifications. Claims concerning engine operability on high IV feedstocks and biodiesel are interrelated. Also, the limitation of feedstock is a major problem for producers as well as for biodiesel trade. In this context, it might be time to re‐evaluate the IV parameter. Based on available data, reports, and experience in this field the enclosed considerations maybe will help to answer the (admittedly provocative) question: Is IV limitation still appropriate? 相似文献
64.
Assessment of urban energy use may proceed by a number of methods. Here we derive an energy account from local statistics, and compare them with an input output (IO) analysis as applied to Melbourne, Australia. These approaches highlight different aspects of urban energy use and comparable outputs are presented together to assess consistency, to identify complementarities and discuss the insight each approach brings to understanding urban energy. The IO method captures the direct and embodied primary energy requirements of local household expenditure (235.8 GJ/capita/year) while the regional assessment more directly accounts for local production activity (258.1 GJ/capita/year). The parity of these results is unexpected for a developed city with a strong tertiary sector. Sectoral detail reveals differences between the primary energy required by Melbourne's economic structure and that ultimately required through the full supply chain relating to household expenditure. This is accompanied by an IO analysis of the geography of Melbourne's ‘energy catchment’. It is suggested that the IO consumption and regional production approaches have particular relevance to policies aimed at consumption behaviour and economic (re)structuring, respectively. Their complementarity further suggests that a combined analysis would be valuable in understanding urban energy futures and economic transitions elsewhere. 相似文献
65.
66.
Versatile high-throughput characterization tools are required for the development of new materials using combinatorial techniques. Here, we describe a modular, high-throughput test stand for the screening of thin-film materials libraries, which can carry out automated electrical, magnetic and magnetoresistance measurements in the temperature range of −40 to 300 °C. As a proof of concept, we measured the temperature-dependent resistance of Fe–Pd–Mn ferromagnetic shape-memory alloy materials libraries, revealing reversible martensitic transformations and the associated transformation temperatures. Magneto-optical screening measurements of a materials library identify ferromagnetic samples, whereas resistivity maps support the discovery of new phases. A distance sensor in the same setup allows stress measurements in materials libraries deposited on cantilever arrays. A combination of these methods offers a fast and reliable high-throughput characterization technology for searching for new materials. Using this approach, a composition region has been identified in the Fe–Pd–Mn system that combines ferromagnetism and martensitic transformation. 相似文献
67.
Yiu Wai Lai Michael Krause Alan Savan Sigurd Thienhaus Nektarios Koukourakis Martin R Hofmann Alfred Ludwig 《Science and Technology of Advanced Materials》2011,12(5)
A high-throughput characterization technique based on digital holography for mapping film thickness in thin-film materials libraries was developed. Digital holographic microscopy is used for fully automatic measurements of the thickness of patterned films with nanometer resolution. The method has several significant advantages over conventional stylus profilometry: it is contactless and fast, substrate bending is compensated, and the experimental setup is simple. Patterned films prepared by different combinatorial thin-film approaches were characterized to investigate and demonstrate this method. The results show that this technique is valuable for the quick, reliable and high-throughput determination of the film thickness distribution in combinatorial materials research. Importantly, it can also be applied to thin films that have been structured by shadow masking. 相似文献
68.
Bjorn Roth Lene Kramer Aase Vorre Skuland Trond Løvdal Sigurd Øines Atle Foss Albert Kjartansson Imsland 《Journal of food science》2014,79(8):S1568-S1574
A total of 18 farmed turbot (Scophthalmus maximus) were slaughtered over 4 successive weeks in November 2012 and stored in polystyrene boxes with ice until analyzed. The fish were stored between 1 and 22 d and presented to a taste panel and further analyzed for quality index method (QIM), microbiological analysis by real‐time quantitative PCR (qPCR), taste, pH, color by computer imaging, protein denaturation with differential scanner calorimeter (DSC), texture hardness, and shear force. Results show small, but significant changes in physical and visual attributes such as texture and color. No gaping was observed. Only small changes in texture were observed explained by lack of myosin denaturation. The fillets became more white and yellow during storage, whereas the major changes occurred during the 1st week. A panel evaluating QIM and taste could not distinguish major differences in appearance and taste and over 15 d storage period, but were able to quantify the age by smell. Analysis of microorganisms on the epidermis displayed growth of Carnobacterium maltaromaticum, potentially inhibiting growth of other spoilage bacteria. Fish stored for 22 d were rejected by the taste panel caused by a stale smell and taste, but not bitter or rancid. It is concluded that turbot has a shelf life of at least 16 d. 相似文献
69.
Identification and analysis of possible splits for azeotropic mixtures—1. Method for column sections
Felix Petlyuk Roman Danilov Stathis Skouras Sigurd Skogestad 《Chemical engineering science》2011,66(12):2512
The identification of possible splits at the finite reflux has been the main challenge for the creation of efficient flowsheets for the separation of azeotropic mixtures. We show in this paper that this problem can be solved by analyzing the mode of infinitely sharp splits, for which trajectories of distillation and pinch lines have special characteristics. The feasibility of sharp splits depends on the relationship of phase equilibrium constants K of components at certain points of the concentration simplex. Pinch branches and bundles of trajectories can arise only when certain relationships of K are satisfied on edges of the concentration simplex. Bundles of trajectories of both sections of column can intersect each other only at complementary relationships of these values at points of components and azeotropes. In this case, there are profiles of concentrations of both sections, which together connect the points of products with each other, i.e., a split is possible. The theory of infinitely sharp split mode determines the mentioned relationships of K. The method of infinitely sharp split mode has been developed on the base of this theory. This method includes the calculation of K at certain points of the concentration simplex. It is not iterative. Therefore, it is very fast, reliable, and can be easily programmed. For the first time, this method covers all n-component azeotropic mixtures, and all types of sharp and half-sharp splits, at which both or one product of column is sharp. This method can find unknown energy-efficient splits for different azeotropic mixtures because it is based on fundamental regularities of distillation. The automatic identification of possible splits is the basis for the synthesis of flowsheets for distillation units and for the conceptual designing of distillation columns. The theory of infinitely sharp split, the method of delimitation of product regions on elements of the concentration simplex for each section of simple columns, and the method of identification of types, characteristics, and terminals of pinch branches are considered in this article. 相似文献
70.
W Deinsberger I Wollesen A J?dicke J Lenzen DK B?ker 《Canadian Metallurgical Quarterly》1997,58(4):171-176
Lumbar disc surgery is frequently performed but only few long-term outcome studies have been published. To assess the socioeconomic long-term outcome after lumbar disc surgery this study was performed using the Functional Economic Rating scale developed by Prolo et al. in 1986. The study group, mailed a questionnaire, consisted of 663 patients (18 to 60 years) operated on in 1983 or 1984. 23 patients (3.5%) died in the follow-up period. 406 (66% male and 34% female) patients answered the questionnaires (61%), therefore being eligible for further investigation. Mean age at the time of operation was 43 +/- 9.5 years. Preoperatively 29% of patients did sedentary work, 46% were employed in less strenuous and 25% in strenuous occupations. A motor deficit was present in 59% of patients preoperatively. In 51% the L4/5 level and in 38% the L5/S1 level was operated; 5% were operated in more than one level. In 45% an intraspinal sequester was found intraoperatively. Intra- and postoperative complications occurred in 14 patients (complication rate 3.4%). Six weeks after surgery all patients were examined in our outpatient department. 93% were more or less relieved of their complaints. 10 years after lumbar disc surgery a good outcome defined as Prolo scale 8-10 was achieved in 38%, a moderate outcome (Prolo scale 6-7) in 40% and a poor outcome (Prolo scale < 5) in 22%, respectively. Patients with strenuous occupations had a significantly (p < 0.001) less favorable outcome than patients with less strenuous or sedentary occupations. 32% were able to work in the previous profession with no restrictions. 42% were able to work part time at the previous occupation or with limited status and 9% had to change their profession. 17% were not able to gain any occupation postoperatively and retired. Vocational consequences depended on the preoperative type of occupation. 54% of patients with strenuous occupations had to change the profession or to retire compared to 15% of patients with sedentary occupations. During the 10-year follow-up period, 125 patients (31%) underwent at least another lumbar disc operation 4.8 +/- 3.8 years after their first surgery. Recurrence at the same level and the same side occurred in 14%. Reoperated patients had a significantly (p < 0.001) less favorable outcome than patients not operated on again. The results of this study indicate the recommendation of a prolonged postoperative course of treatment, especially in patients with strenuous occupations. 相似文献