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Schematic Diagram (schematic + diagram)
Selected AbstractsNonlinear optical microscopy of cellular structuresLASER PHYSICS LETTERS, Issue 1 2004G.I. Petrov Abstract We propose a novel nonlinear optical spectroscopic technique H-CARS (Hyper Coherent Anti-Stokes Raman Spectroscopy) to allow imaging of biological structures in real time. Schematic diagram illustrating spectroscopic imaging of cellular membranes using H-CARS microscopy (© 2004 by HMS Consultants. Inc. Published exclusively by WILEY-VCH Verlag GmbH & Co.KGaA) [source] Thermoplastic Acrylic Rubber Physically Crosslinked by Tiny Poly(vinylidene fluoride) CrystalsMACROMOLECULAR MATERIALS & ENGINEERING, Issue 10 2006Yongjin Li Abstract Summary: Acrylic rubber showed greatly improved mechanical properties and very nice elasticity when blended with small amount of PVDF. PVDF crystallized into very sparse and loose spherulites in the blends with ACM molecular chains incorporated into the PVDF lamellae. These micro-crystals were precisely dispersed in the ACM matrix and acted as the physical crosslink points for the matrix upon stretching. Therefore, the ACM/PVDF blends containing small amounts of PVDF display the typical properties of thermoplastic elastomers with large elongation at break, high tensile strength, and excellent strain recovery from the highly deformed state. Schematic diagram of physically crosslinked ACM by the tiny PVDF crystals in ACM-rich PVDF/ACM blends. [source] Preparation and Properties of PVC Ternary Nanocomposites Containing Elastomeric Nanoscale Particles and Exfoliated Sodium-MontmorilloniteMACROMOLECULAR MATERIALS & ENGINEERING, Issue 6 2006Qingguo Wang Abstract Summary: A novel rigid PVC ternary nanocomposite containing NBR-ENP and untreated Na-MMT has been fabricated. X-ray diffraction XRD, TEM and SEM observations revealed that the untreated Na-MMT was exfoliated and most NBR-ENPs (about 90 nm) were separately dispersed in the PVC matrix. DMTA and TGA demonstrated that the PVC ternary nanocomposites had a higher glass transition temperature and a higher decomposition temperature than neat PVC, while the toughness increased simultaneously. Combustion tests showed that the exfoliated clay in the PVC/NBR-ENP/MMT ternary nanocomposites did not improve the flame retardancy after ignition under strong heat flux. Schematic diagram of the fabrication procedure of PVC/NBR-ENP/Na-MMT ternary nanocomposites. [source] Co-continuous Polyamide 6 (PA6)/Acrylonitrile-Butadiene-Styrene (ABS) NanocompositesMACROMOLECULAR RAPID COMMUNICATIONS, Issue 9 2005Yongjin Li Abstract Summary: Polyamide 6 (PA6)/acrylonitrile-butadiene-styrene (ABS) (40/60 w/w) nanocomposites with a novel morphology were prepared by the melt mixing of PA6, ABS and organoclay. The blend nanocomposites had a co-continuous structure, in which both PA6 and styrene-acrylonitrile (SAN) were continuous phases. It was found that the toughening rubber particles were only located in the SAN phase and the strengthening clay platelets were selectively dispersed in the PA6 phase. The co-continuous nanocomposites showed greatly improved mechanical properties over the whole temperature range when compared with the same blend sample without clay. Schematic diagram for the co-continuous ABS/PA6 blend nanocomposite. [source] Polymer-Based Rectifying Diodes on a Glass Substrate Fabricated by Ink-Jet PrintingMACROMOLECULAR RAPID COMMUNICATIONS, Issue 4 2005Yi Liu Abstract Summary: The fabrication of polymer diodes on a glass substrate by an ink-jet printing technique is reported. Both an n-type semiconductive polymer, poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-(1-cyanovinylene)phenylene] (CN-PPV), and a p-type semiconductive polymer, polypyrrole (PPy) or poly(3,4-ethylenedioxythiophene) (PEDOT), were printed through a piezoelectric ink-jet printer. The printed CN-PPV/PPy and CN-PPV/PEDOT diodes showed good rectifying characteristics. These results indicate the potential of the low-cost ink-jet printing technique to produce polymer microelectronic devices and circuits. Schematic diagram of the printed polymer diode [source] Novel thermally and mechanically stable hydrogel for enzyme immobilization of penicillin G acylase via covalent techniqueJOURNAL OF APPLIED POLYMER SCIENCE, Issue 6 2008Magdy M. M. Elnashar Abstract ,-Carrageenan hydrogel crosslinked with protonated polyethyleneimine (PEI+) and glutaraldehyde (GA) was prepared and evaluated as a novel biocatalytic support for covalent immobilization of penicillin G acylase (PGA). The method of modification of the carrageenan biopolymer is clearly illustrated using a schematic diagram and was verified by FTIR, elemental analysis, DSC, and INSTRON using the compression mode. Results showed that the gels' mechanical strength was greatly enhanced from 3.9 kg/cm2 to 16.8 kg/cm2 with an outstanding improvement in the gels thermal stability. It was proven that, the control gels were completely dissolved at 35°C, whereas the modified gels remained intact at 90°C. The DSC thermogram revealed a shift in the endothermic band of water from 62 to 93°C showing more gel-crosslinking. FTIR revealed the presence of the new functionality, aldehydic carbonyl group, at 1710 cm,1 for covalent PGA immobilization. PGA was successfully immobilized as a model industrial enzyme retaining 71% of its activity. The enzyme loading increased from 2.2 U/g (control gel) to 10 U/g using the covalent technique. The operational stability showed no loss of activity after 20 cycles. The present support could be a good candidate for the immobilization of industrial enzymes rich in amino groups, especially the thermophilic ones. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 [source] Monte Carlo Simulation of Degradation of Porous Poly(lactide) Scaffolds, 1MACROMOLECULAR THEORY AND SIMULATIONS, Issue 9 2006Effect of Porosity on pH Abstract Summary: Monte Carlo method was used to simulate the degradation of porous PLA scaffolds. The simulated volume was assumed to be divided homogeneously between the pore and solid PLA with the ratio equal to the bulk porosity of the scaffold. The volume was divided into surface and bulk elements where the surface elements were in direct contact with the aqueous degradation medium, while the bulk elements were surrounded by the pore and solid PLA. The effect of degradation time on PLA ester groups and carboxylic acid end-groups for surface and bulk elements, pH, PLA degradation rate and mass loss, and PLA molecular weight distribution was simulated. For surface elements, pH remained constant at 7.4 over the entire time of degradation, while for bulk elements its value decreased significantly to as low as 5.8. The highest drop in pH within the scaffold was observed for the highest porosity of 90%. There was a lag time of at least 7 weeks in the mass loss for surface as well as bulk elements for porosities ranging from 70 to 90%. The mass loss for bulk elements was considerably faster than the surface elements. This difference in the rate of mass loss between the surface and bulk elements could affect the 3D morphology and dimensional stability of the scaffold in vivo as degradation proceeds. The simulation predicts that, due to differences in the rate of bulk and surface degradation, hollow structures could form inside the scaffold after 19, 17, and 15 weeks for initial porosities of 70, 80, and 90%, respectively. A schematic diagram illustrating the degradation of an element on the outer surface of the scaffold (surface element) versus an element within the volume of the scaffold (bulk element). [source] Free IAA in stigmas and styles during pollen germination and pollen tube growth of Nicotiana tabacumPHYSIOLOGIA PLANTARUM, Issue 1 2008Dan Chen Although many studies have emphasized the importance of auxin in plant growth and development, the thorough understanding of its effect on pollen,pistil interactions is largely unknown. In this study, we investigated the role of free IAA in pollen,pistil interactions during pollen germination and tube growth in Nicotiana tabacum L. through using histo and subcellular immunolocalization with auxin monoclonal antibodies, quantification by HPLC and ELISA together with GUS staining in DR5::GUS -transformed plants. The results showed that free IAA in unpollinated styles was higher in the apical part and basal part than in the middle part, and it was more abundant in the transmitting tissue (TT). At the stage of pollen germination, IAA reached its highest content in the stigma and was mainly distributed in TT. After the pollen tubes entered the styles, the signal increased in the part where pollen tubes would enter and then rapidly declined in the part where pollen tubes had penetrated. Subcellular localization confirmed the presence of IAA in TT cells of stigmas and styles. Accordingly, a schematic diagram summarizes the changing pattern of free IAA level during flowering, pollination and pollen tube growth. Furthermore, we presented evidence that low concentration of exogenous IAA could, to a certain extent, facilitate in vitro pollen tube growth. These results suggest that IAA may be directly or indirectly involved in the pollen,pistil interactions. Additionally, some improvements of the IAA immunolocalization technique were made. [source] Molecular-Recognition and Binding Properties of Cyclodextrin-Conjugated PolyrotaxanesCHEMPHYSCHEM, Issue 8 2006Hak Soo Choi Dr. Sliding and rotation of cyclodextrins (CDs) along the polymer main chain of polyrotaxanes significantly increases the binding ability for and molecular recognition of guest molecules by multifaceted inclusion complexation (see schematic diagram). The cyclodextrin-conjugated polyrotaxanes were obtained by attaching ,-CDs to an ,-CD/poly(ethylene glycol) polyrotaxane backbone via peptide bonds. [source] Database of queryable gene expression patterns for XenopusDEVELOPMENTAL DYNAMICS, Issue 6 2009Michael J. Gilchrist Abstract The precise localization of gene expression within the developing embryo, and how it changes over time, is one of the most important sources of information for elucidating gene function. As a searchable resource, this information has up until now been largely inaccessible to the Xenopus community. Here, we present a new database of Xenopus gene expression patterns, queryable by specific location or region in the embryo. Pattern matching can be driven either from an existing in situ image, or from a user-defined pattern based on development stage schematic diagrams. The data are derived from the work of a group of 21 Xenopus researchers over a period of 4 days. We used a novel, rapid manual annotation tool, XenMARK, which exploits the ability of the human brain to make the necessary distortions in transferring data from the in situ images to the standard schematic geometry. Developmental Dynamics 238:1379,1388, 2009. © 2009 Wiley-Liss, Inc. [source] | |||||||||||||