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A series of hyperbranched alternating copolymers were synthesized by either Suzuki or Grignard coupling polycondensation reactions between two AB4-type tetrahedral monomers [tetra(4-bromobiphenyl)silane (1) and tetra(2-bromo-9,9-dihexylfluorenyl)silane (2)] with AB2-type dibromo or diboronic acid monomers of 9,9-dihexylfluorene or oligothiophenes. Polymers (3, 5−8) (derived from 1 and 9,9-dihexylfluorene-2,7-diboronic acid, 2,2‘-bithiophene-5,5‘-diboronic acid, 2,2‘:5‘,2‘ ‘-terthiophene-5,5‘ ‘-diboronic acid, 5,5‘-dibromo-3,3‘-dihexyl-2,2‘-bithiophene, and 5,5‘ ‘-dibromo-3,3‘-dihexyl-2,2‘:5‘,2‘ ‘-terthiophene, respectively) emitted blue to red light in the solid state and their absorption and emission maxima were red shifted with the increase in conjugation length. Polymer 4 (derived from 2 and 9,9-dihexylfluorene-2,7-diboronic acid) emitted blue light highly efficiently in both solution and the condensed state, but its absorption and emission maxima were slightly blue-shifted from those of 3, revealing that no effective electron delocalization occurred among the fluorene units. Polymer 9 (derived from 2 and 5,5‘-dibromo-3,3‘-dihexyl-2,2‘-bithiophene) emitted intense blue light in solution with only the structured peaks from the fluorene units being observed in its PL spectra. The film of 9 emitted green light and emissions from both the fluorene and bithiophene chromophores were observed in the PL spectra with the latter being stronger, due to the intramolecular energy transfer from fluorene units to bithiophene units. The ab initio studies were carried out to elucidate the intrigue optical properties of the present hyperbranched polymers. Double layer devices with configurations ITO/PEDOT/polymer (4 or 7)/LiF/Ca/Ag, which emitted blue and green light, respectively, were fabricated and preliminary data on the device performances are reported. We present two strategies for the design and synthesis of RGB-emitting hyperbarched polymers:  (1) using a structurally not crowded core 1 and adjusting the emission by conjugation length; (2) using a structurally crowded core 2 and adjusting the light emission by intramolecular energy transfer.

The first soluble hyperbranched tetrahedral polymers were prepared by Suzuki coupling polycondensation reaction between tetrabromoarylmethane/silane and 9,9-dihexylfluorene-2,7-diboronic acid at low concentrations. The polymers exhibited high thermal stability with their decomposition temperatures (Tds) in the range 352−449 °C. The polymers emitted blue light highly efficiently in both solution and the solid state. The photoluminescence quantum efficiencies of the polymers in THF solution were in the range 73−99%, and those in thin films were 38−82%. The film PL spectra of the polymers exhibited similar spectral patterns to those determined in solutions, with 1−8 nm red shift in their emission maxima and 0−8 nm increase in their full width at half-maximum (fwhm) values being observed. No long wavelength excimer-like emissions at 500−600 nm, which were typical for polyfluorenes due to their self-aggregation in the solid state, were observed. Thus, the polymers were less prone to self-aggregation in the solid state due to their hyperbranched structures. A double-layer polymer light-emitting diode (PLED) device with a configuration of ITO/PEDOT/polymer/LiF/Ca/Ag was fabricated. The device showed bright blue emission peaking at 415 nm with an external quantum efficiency of 0.6% and a turn voltage at 6.0 V. The synthetic simplicity, good solubility and solution processability, high PL quantum efficiencies in solution and the solid state, and nonaggregating property in the solid state would make the present polymers a novel class of blue emitters.

Introduction: Enhancement of facial beauty is one of the primary goals of patients seeking facial rejuvenation treatment. The lower third of the face, which is affected by the dentoalveolar complex, has a major impact on the perception of facial esthetics. This article aims to educate cosmetic surgeons about the impact that cosmetic dentistry can have on creating facial harmony and esthetics.Methods: A simple method of bioesthetic dental evaluation of the patient and common cosmetic dental procedures are discussed.Discussion: The importance of a multidisciplinary and multimodality approach by both the cosmetic surgeon and the cosmetic dentist toward creating a more complete, harmonious facial esthetic is emphasized.Results: As demonstrated by figures representative of typical cases, a combined cosmetic surgery and cosmetic dental approach yields excellent esthetic results.Conclusion: The incorporation of fundamental principles of proper smile design and dental esthetics into a facial enhancement treatment plan can achieve excellent results on a consistent basis.

The performance of three different types of dryers for the hot air drying of sawn-limber planks are compared. These were the electric resistance dryer, solar dryer, and the dehumidifier dryer. Whilst the electric and solar dryers depended only upon hot air for drying, the dehumidifier dryer relied on hot dehumidified air. The results of investigations carried out on timber drying employing these three types of dryers in the Engineering Faculty are compiled and compared here in this paper. The results showed that the electric dryer produced the fastest drying lime and lowest moisture content, followed by dehumidifier drying. The solar dryer achieved a lower moisture content and a faster drying rate compared to natural drying, although the difference in drying times was marginal.

Solar dryers have been considered for timber drying in a number of countries because of the expected savings in drying costs. From a review of past works on solar, natural, and conventional drying it was observed that while solar dryers were able to dry timber faster compared to natural drying, the difference was only marginal in some instances. The drying rates are expected to be dependent upon ambient conditions in which the dryera are operated. Solar dryers would operate more efficiently in countries with low humidity than in tropical regions. Thus the thermal performance and also the economics of solar dryer is country dependent. In the present paper, a comparison of the drying rates obtained with a solar dryer is made with that obtained with an electrically operated drying kiln.

An experimental investigation use conducted on the performance of a solar box dryer for drying bamboo operating under tropical rearher conditions. The dryer is a greenhouse-type designed for multi-crap solar drying. Air circulation was by electrically-operated fan. The results shoved that the moisture content of the bamboo could be brought down to about 19% from an initial value of nearly 90% in 17 days by operating the dryer over 8 hours each day. Under natural drying conditiona. the final moisture content reached was only 12%. Although eolar drying of bamboo vaa only marginally faster than nacural drying. noncrhelesa. final moisture content was lower.

An experimental investigation was conducted on the performance of a solar box dryer for drying bamboo operating under tropical weather conditions. The dryer is a greenhouse-type designed for multi-crop solar drying. Air circulation was by electrically-operated fan. The results showed that the moisture content of the bamboo could be brought dovn to about 19% from an initial value of nearly 90% in 17 days by operating the dryer over 8 hours each day. under natural drying conditions, the final moisture content reached was only 22%. Although solar drying of bamboo was only marginally faster than natural drying. nonetheless. final moisture content was lower.

The reaction of methyl 2-O-acetyl-4,6-O-benzylidene-3-deoxy-3-nitro-β-D-glucopyranoside (1) or of methyl 4,6-O-benzylidene-2,3-dideoxy-3-nitro-β-D-erythro-hex-2-enopyranoside (2) with nitroalkanes led to branched-chain dinitro sugar derivatives, namely methyl 4,6-O-benzylidene-2,3-dideoxy-3-nitro-2-nitroalkyl-β-D-glucopyranosides (3). The nitroalkanes employed included nitromethane, nitroethane, 1-and 2-nitropropane, and methyl nitroacetate. The three first-mentioned nitroalkanes were added in similar fashion to methyl 4,6-O-benzylidene-2,3-dideoxy-3-nitro-β-D-threohex-2-enopyranoside (5) to give methyl 4,6-O-benzylidene-2,3-dideoxy-3-nitro-2-nitroalkyl-β-D-galactopyranosides (6). Analogous reactions of 1and 5with diethyl malonate produced the corresponding branched-chain glycosides 7and 8. The reactions appear to be highly stereoselective as far as the configurations at C-2 and C-3 in the products are concerned. However, there is evidence for the formation of side-chain epimers in three cases where the nitroalkyl side chain possesses an asymmetric carbon.

The failure mode effect analysis (FMEA) aims to strengthen the operational performance of a process of a product. However, current FMEA practice does not quantify the achievement in operational performances. Risk priority number (RPN), the only success indicator of FMEA, is independent of operational performance monitoring. Thus, the capability of FMEA to strengthen operational performance may be ineffectual unless it demonstrates a quantifiable improvement in operational performance. This study offered guidelines for manufacturing industry to quantify the operational performance within the FMEA methodology by operational performance indicator (OPI). In tandem with RPN, the OPI in FMEA ascertains the priority set by RPN and defines more refined priority than RPN. Design for manufacturing and assembly (DFMA) and Poka-yoke provide systematic guidelines for developing corrective actions for eliminating or reducing the occurrence of failure while strengthening current control to prevent the delivery of any non-conformance to customers. Application of the new FMEA-based integrated framework in a semiconductor manufacturer in Malaysia demonstrated that 69.2% improved the overall equipment efficiency (OEE).