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61.
Preparation of starch microspheres using epichlorohydrin is a time consuming method and requires around 18 hr for cross-linking reaction. To reduce reaction time, terbutaline sulfate (TBS) loaded degradable starch microspheres (DSM) were prepared using formaldehyde as the cross-linking agent. All microspheres were spherical in shape and had a porous, rough surface with a mean particle size of 18-24 microm. Whatever the cross-linking time, it was seen that the release of the TBS was not complete during the release experiments. The influence of enzyme on the degradation of microspheres was moderate. Following intravenous administration, initial uptake of microspheres by the lung was higher than those of other organs.  相似文献   
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Synthesis and processing techniques have now been established for obtaining high quality monodisperse nanocrystals of various metallic and semiconducting materials, fullerenes of distinct properties, single- and multi-wall carbon nanotubes, polymeric dendrimers with tailored functionalities, as well as other nanophase constructs. The next key step towards novel applications of nanostructured materials concerns their positioning, arrangement, and connection into functional networks without mutual aggregation. In this review, we highlight the recent progress of using anthracene- and pyrene-based self-assembling molecules with tunable energetic (pi-pi interactions, hydrogen bonding, dipole-dipole interactions) and variable geometries to create stable, highly ordered, and rigid self-assembled monolayer (SAM) templates with adjustable superlattices on crystalline substrates. Based on aromatic SAM templates, stable and highly ordered self-assembled structures of optoelectronically active C60 have been obtained and shown to exhibit desirable electrical and optoelectronic properties, such as nonlinear transporting effect for molecular electronics and efficient photocurrent generation for mimicking photosynthesis in nature. By using genetically engineered polypeptides with surface recognition for specific inorganics, selective integration of nanoparticles onto aromatic SAM templates have also been realized. Through a combination of spatially confined surface chemical reaction and microcontact printing, sub-micron arrays of peptide-organic hybrid conjugates were successfully generated to serve as templates to achieve the patterned assembly of nanoparticles.  相似文献   
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The axial heat processing (AHP) crystal growth technique was used to investigate the morphological stability of faceted solid/liquid (s/l) interfaces. Six Sb-doped Ge single crystals containing 2.3 × 10−2 to 2.3 × 10−1 at. pct Sb were grown at pulling rates of 10 to 20 mm/h. These include two bicrystals specifically designed to investigate the effect of slight misorientation on stability. Faceted growth with a kinetic supercooling on the order of 0.15 K was achieved, and a characteristic two-dimensional W instability boundary, an inverted crater in three dimensions, was observed. The crystals exhibited enhanced morphological stability over the predictions of the constitutional supercooling (CS) criterion and the Mullins and Sekerka (MS) stability criterion, with the highest stability in the center of the W. These results are examined with current analytical stability theories accounting for convection and kinetics. An alternate model is proposed based on anisotropic kinetics and the competition between lateral spreading on a faceted interface and the amplification rate of an interfacial perturbation.
Reza Abbaschian (Dean and Professor)Email:
  相似文献   
64.
Receiving patents or licenses is an inevitable act of research in order to protect new ideas leading innovation. Request for patents has increased exponentially in order to legalize the intellectual property. Measuring economical value of each patent has been widely studied in the literature. Majority of the research in this field is focused on the patent driver prospect handled for the patent offices. There are a variety of criteria affecting decisions on each patent right; and predicting the possibility of grant may help the researchers to take some precautions. Objective of this study is to propose a robust model to determine if the appeal has a chance of approval. A case study is run on the patents that are accepted and rejected in home appliance industry to construct an intelligent classification model. The support vector machine, Back-Propagation Network and Bayes classification methods are compared on the proposed model. The proposed model in this study will help the decision makers to predict whether the patent appeal will be accepted. The study is unique with the approach that helps the candidate patent owners.  相似文献   
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k-Anonymity is a method for providing privacy protection by ensuring that data cannot be traced to an individual. In a k-anonymous dataset, any identifying information occurs in at least k tuples. To achieve optimal and practical k-anonymity, recently, many different kinds of algorithms with various assumptions and restrictions have been proposed with different metrics to measure quality. This paper evaluates a family of clustering-based algorithms that are more flexible and even attempts to improve precision by ignoring the restrictions of user-defined Domain Generalization Hierarchies. The evaluation of the new approaches with respect to cost metrics shows that metrics may behave differently with different algorithms and may not correlate with some applications’ accuracy on output data.  相似文献   
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Garzan oil field is located at the south east of Turkey. It is a mature oil field and the reservoir is fractured carbonate reservoir. After producing about 1% original oil in place (OOIP) reservoir pressure started to decline. Waterflooding was started in order to support reservoir pressure and also to enhance oil production in 1960. Waterflooding improved the oil recovery but after years of flooding water breakthrough at the production wells was observed. This increased the water/oil ratio at the production wells. In order to enhance oil recovery again different techniques were investigated. Chemical enhanced oil recovery (EOR) methods are gaining attention all over the world for oil recovery. Surfactant injection is an effective way for interfacial tension (IFT) reduction and wettability reversal. In this study, 31 different types of chemicals were studied to specify the effects on oil production. This paper presents solubility of surfactants in brine, IFT and contact angle measurements, imbibition tests, and lastly core flooding experiments. Most of the chemicals were incompatible with Garzan formation water, which has high divalent ion concentration. In this case, the usage of 2-propanol as co-surfactant yielded successful results for stability of the selected chemical solutions. The results of the wettability test indicated that both tested cationic and anionic surfactants altered the wettability of the carbonate rock from oil-wet to intermediate-wet. The maximum oil recovery by imbibition test was reached when core was exposed 1-ethly ionic liquid after imbibition in formation water. Also, after core flooding test, it is concluded that considerable amount of oil can be recovered from Garzan reservoir by waterflooding alone if adverse effects of natural fractures could be eliminated.  相似文献   
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