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1.
Molecular structure and granule morphology of native and heat‐moisture‐treated pinhão starch 下载免费PDF全文
Vania Z. Pinto Khalid Moomand Nathan L. Vanier Rosana Colussi Franciene A. Villanova Elessandra R. Zavareze Loong‐Tak Lim Alvaro R. G. Dias 《International Journal of Food Science & Technology》2015,50(2):282-289
Pinhão seed is an unconventional source of starch and the pines grow up in native forests of southern Latin America. In this study, pinhão starch was adjusted at 15, 20 and 25% moisture content and heated to 100, 110 and 120 °C for 1 h. A decrease in λ max (starch/iodine complex) was observed as a result of increase in temperature and moisture content of HMT. The ratio of crystalline to amorphous phase in pinhão starch was determined via Fourier transform infra red by taking 1045/1022 band ratio. A decrease in crystallinity occurred as a result of HMT. Polarised light microscopy indicated a loss of birefringence of starch granules under 120 °C at 25% moisture content. Granule size distribution was further confirmed via scanning electron microscopy which showed the HMT effects. These results increased the understanding on molecular and structural properties of HMT pinhão starch and broadened its food and nonfood industrial applications. 相似文献
2.
Mubasher A. Bashir 《Polymer》2005,46(10):3223-3229
Gradient chromatography was applied in order to calculate the composition at elution for different methacrylates on normal phase columns. In addition the composition at elution was determined for polyethyleneoxide on a reverse phase column. It is shown that high molar mass polymers elute for a given homopolymer irrespective of their molar mass at the same eluent composition, which varies only slightly with gradient slope. In general the composition at elution in gradient chromatography is expected to be slightly lower than the true critical composition. For high molar mass polymers we found this composition to be close to the critical composition determined by isocratic experiments. The difference between the composition at elution and the true critical composition for a variety of polymethacrylates and for polyethyleneglycol was found to be only between 0.2 and 5%. Thus, after estimating the composition at elution, only a small number of additional isocratic experiments is needed to find the exact critical composition. 相似文献
3.
A novel isolation scheme named planarized trench isolation and field oxide formation using poly-silicon (PLATOP) Is described. PLATOP is applicable to high-performance submicron VLSI since it results in encroachment-free shallow trenches, and planarized field oxide. The process offers poly silicon-filled deep trenches. The process also relies on noncritical lithography and novel etch processes to planarize the deposited poly-silicon from the top of the active areas, and oxidation to consume the poly-silicon in the field regions. Electrical results are presented proving the viability of the isolation scheme 相似文献
4.
Anmar W. Sabri Zainab H. Ali Serwan F. Shawkat Lamia A. Thejar Thaer I. Kassim Khalid A. Rasheed 《河流研究与利用》1993,8(3):237-250
The influences of the Samarra impoundment on the ecology of the downstream sector of the river Tigris are investigated. Zooplankton were collected monthly from July 1987 to July 1988. It was found that zooplankton were most abundant during high river discharges in March. During the month of low river discharge, September, the zooplankton population was greatly reduced immediately below the barrage and remained so to the last downstream station. Several factors seem to explain such differences. The high discharge from the impoundment was found to be the dominating factor and may flush the small backwaters in which zooplankton were abundant, thus increasing the population in the river. Zooplankton species vary in their ability to sustain populations in the river, variations which are due mainly to species-specific characteristics. 相似文献
5.
Marcus T. Schmitz Bashir M. Al-Hashimi Petru Eles 《Design Automation for Embedded Systems》2002,6(4):401-424
In this paper, we introduce the LOPOCOS (Low Power Co-synthesis) system, a prototype CAD tool for system level co-design. LOPOCOS targets the design of energy-efficient embedded systems implemented as heterogeneous distributed architectures. In particular, it is designed to solve the specific problems involved in architectures that include dynamic voltage scalable (DVS) processors. The aim of this paper is to demonstrate how LOPOCOS can support the system designer in identifying energy-efficient hardware/software implementations for the desired embedded systems. Hence, highlighting the necessary optimization steps during design space exploration for DVS enable architectures. The optimization steps carried out in LOPOCOS involve component allocation and task/communication mapping as well as scheduling and dynamic voltage scaling. LOPOCOS has the following key features, which contribute to this energy efficiency. During the voltage scaling valuable power profile information of task execution is taken into account, hence, the accuracy of the energy estimation is improved. A combined optimization for scheduling and communication mapping based on genetic algorithm, optimizes simultaneously execution order and communication mapping towards the utilization of the DVS processors and timing behaviour. Furthermore, a separation of task and communication mapping allows a more effective implementation of both task and communication mapping optimizationsteps. Extensive experiments are conducted to demonstrate the efficiency of LOPOCOS. We report up to 38% higher energy reductions compared to previous co-synthesis techniques for DVS systems. The investigations include a real-life example of an optical flow detection algorithm. 相似文献
6.
Khalid Mahmood Zia Mehdi Barikani Ijaz Ahmad Bhatti Mohammad Zuber Haq Nawaz Bhatti 《应用聚合物科学杂志》2008,109(3):1840-1849
A series of polyurethane (PU) elastomers was prepared by the reaction of poly(?‐caprolactone) and 4,4′‐diphenylmethane diisocyanate, which was extended with a series of chain extenders (CEs) having 2–10 methylene units in their structure. The completion of the reaction was confirmed by Fourier transform infrared spectroscopy. The chemical structures of the synthesized PU samples were characterized with Fourier transform infrared, 1H‐NMR, and 13C‐NMR spectroscopy, and the thermal properties were determined by thermogravimetric analysis, DSC, and dynamic mechanical thermal analysis techniques. The mechanical properties were also studied and are discussed. The thermogravimetric analysis and DSC analysis showed that CE length had a considerable effect on the thermal properties of the prepared samples. The dynamic mechanical thermal analysis and damping peaks were also affected by the number of methylene units in the CE length. The elastomer extended with 1,2‐ethane diol exhibited optimum thermal properties, whereas the elastomer based on 1,10‐decane diol displayed the worst thermal properties. Tensile strength and elongation at break decreased with increasing CE length, whereas hardness showed the opposite trend. The glass‐transition temperature moved toward lower temperatures with increasing CE length. The decrease in the glass‐transition temperature and tensile properties were interpreted in terms of decreasing hard segments and increasing chain flexibility. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
7.
Khalid KASSARA 《控制理论与应用(英文版)》2012,10(3):303-308
The aim of this paper is to propose a new way to deal with observability of systems governed by ODEs, in a more general setting than the standard output equation.The primary finding is that observability over a time horizon reduces to single-valuedness of the vertical section of a set we name the observability kernel.The latter consists of the viability kernel of the output domain under the augmented system.The approach may be used either for global or local observability,to which available results on single-valuedness of multifunctions shall be applied in order to get necessary and/or sufficient characterizing conditions.Several examples are provided in order to illustrate the method. 相似文献
8.
Autonomous mapping of HL7 RIM and relational database schema 总被引:1,自引:0,他引:1
Shagufta Umer Muhammad Afzal Maqbool Hussain Khalid Latif Hafiz Farooq Ahmad 《Information Systems Frontiers》2012,14(1):5-18
Healthcare systems need to share information within and across the boundaries in order to provide better care to the patients.
For this purpose, they take advantage of the full potential of current state of the art in healthcare standards providing
interoperable solutions. HL7 V3 specification is an international message exchange and interoperability standard. HL7 V3 messages
exchanged between healthcare applications are ultimately recorded into local healthcare databases, mostly in relational databases.
In order to bring these relational databases in compliance with HL7, mappings between HL7 RIM (Reference Information Model)
and relational database schema are required. Currently, RIM and database mapping is largely performed manually, therefore
it is tedious, time consuming, error prone and expensive process. It is a challenging task to determine all correspondences
between RIM and schema automatically because of extreme heterogeneity issues in healthcare databases. To reduce the amount
of manual efforts as much as possible, autonomous mapping approaches are required. This paper proposes a technique that addresses
the aforementioned mapping issue and aligns healthcare databases to HL7 V3 RIM specifications. Furthermore, the proposed technique
has been implemented as a working application and tested on real world healthcare systems. The application loads the target
healthcare schema and then identifies the most appropriate match for tables and the associated fields in the schema by using
domain knowledge and the matching rules defined in the Mapping Knowledge Repository. These rules are designed to handle the
complexity of semantics found in healthcare databases. The GUI allows users to view and edit/re-map the correspondences. Once
all the mappings are defined, the application generates Mapping Specification, which contains all the mapping information
i.e. database tables and fields with associated RIM classes and attributes. In order to enable the transactions, the application
is facilitated with the autonomous code generation from the Mapping Specification. The Code Generator component focuses primarily
on generating custom classes and hibernate mapping files against the runtime system to retrieve and parse the data from the
data source—thus allows bi-directional HL7 to database communication, with minimum programming required. Our experimental
results show 35–65% accuracy on real laboratory systems, thus demonstrating the promise of the approach. The proposed scheme
is an effective step in bringing the clinical databases in compliance with RIM, providing ease and flexibility. 相似文献
9.
Summary The synthesis of telechelic monodispersed diols produced from the radical telomerization of an excess of undecylenol with commercialy available , -dithiols HSC2H4XC2H4SH (X=0, S or CH2) initiated by peroxides is presented. In each case, the diols were obtained selectively and quantitatively and they were characterized by both 1H and 13C NMR. Their physical characteristics (Tg, Tm and decomposition temperatures) were determined. Such compounds are thermally more stable than polydispersed telechelic commercially available diols. 相似文献
10.
Rajivgandhi Govindan Nadar Chenthis Kanisha Chelliah Vijayakumar Sekar Alharbi Naiyf S. Kadaikunnan Shine Khaled Jamal M. Alanzi Khalid F. Li Wen-Jun 《Journal of Inorganic and Organometallic Polymers and Materials》2021,31(10):3921-3933
Journal of Inorganic and Organometallic Polymers and Materials - The silver oxide nanoparticle was successfully synthesized using floral waste by simple one pot, cost effective method. The complete... 相似文献