Standard Glass Plate Research Articles

Robotic Catalysis: A High‐Throughput Method for Miniature Screening of Mesoporous Metal Oxides**

AbstractWe have developed a high‐throughput system to synthesise and explore up to 96 heterogeneous catalysts at the same time. The system was developed as a proof of concept, using a standard glass plate and a 3D printed 96‐well plate. Nano‐droplets of catalyst formulations were transferred to the glass plate using an acoustic liquid handler and upon heat treatments, the miniature mesoporous metal oxide (MMO) catalysts were formed. The 3D printed bottomless 96‐well plate was fixed to the glass plate, to give 96 individual wells, each containing a catalyst. Four catalyst plates were prepared (Co3O4‐, Au/Co3O4‐, Pd/Co3O4‐ and Co/Mn‐MMO) to be screened for their activity in the oxidation of morin, as a model reaction. The observed reaction rates (kobs) for each catalyst were calculated to identify the most active catalyst. The general method described herein requires microscopic amounts of catalysts with derivates of the catalyst's composition.

Validation of a method to quantify microfibres present in aquatic surface microlayers

Many of the methods for microplastics quantification in the environment are criticised creating problems with data validity. Quantification of microplastics in the surface microlayer of aquatic environments using glass plate dipping holds promise as a simple field method, but its efficiency has yet to be validated. We tested a standard glass plate dipping method to assess recovery of four common polymer microfibres and two common natural fibres, under three different salinities (freshwater, brackish water, saltwater). Overall recovery rates were low (26.8 ± 1.54%) but higher recoveries were observed under saltwater treatments (36.5 ± 3.01%) than brackish water (24.5 ± 1.92%) or freshwater (19.3 ± 1.92%). The fibre types showed different recovery rates, with acrylic yielding significantly higher recovery rates (37.0 ± 2.71%) than other fibres across treatments. No clear relationship between the density of the fibres and the recovery efficiency was seen. We suggest that, where this method is used for monitoring microplastics, the results will typically underestimate the total amount present, but that recovery is sufficiently consistent to allow comparison of differences between sampling locations. When comparing data across river-estuarine or similar transects salinity should be monitored to account for salinity-induced differences in sampling recovery.

Condensation and Radiation Transmittance of Greenhouse Cladding Materials, Part 2: Results for a Complete Condensation Cycle

The radiation transmittances of a standard glass plate and an ordinary polyethylene (PE) film were measured during a complete condensation cycle (dry phase; condensation without run-off; condensation with run-off evaporation phase). The measurements were performed in a specially developed laboratory measuring unit, using perpendicularly polarized monochromatic radiation in the range of photosynthetically active radiation (PAR). Transmittances were determined for three angles of incidence: 0, 30, and 60°. In the dry phase, at normal incidence, the transmittance of the ordinary PE film (about 90% was almost similar to the one of the standard glass plate (about 89%). For increasing incidence angles, the transmittance of both dry cladding materials decreased. As soon as condensate was formed, a quick decrease of the transmittance was found for the PE film for the three angles of incidence (23% at normal incidence). This transmittance decrease adopted an equilibrium value after approximately 1 h. On the glass plate, however, the quick drop of the transmittance was only observed for higher incidence angles. At normal incidence, the effect of condensate on the transmittance of the glass plate was found to be negligible. In most cases, the occurrence of run-off caused a slight change of the transmittance of both cladding materials with respect to the phase of condensation without run-off. As soon as the evaporation of the condensate started, the transmittance returned gradually to its original value for the dry state. In general, it can be stated that the effects of condensation on the radiation transmittance were greater on the PE film than on the glass plate.

WETTABILITY AND HIGH INCIDENCE ANGLE LIGHT TRANSMITTANCE OF GREENHOUSE CLADDINGS

The effects of condensate on the transmittance of a vertical standard polyethylene film and a vertical standard glass plate were investigated to verify whether condensate on a greenhouse cladding material could increase the transmittance at high angles of incidence as predicted in literature. At an incidence angle of 80°, a mean transmittance increase of about 4% was measured when condensate was present on the polyethylene film. On the glass plate, however, a transmittance decrease of about 5% was measured under similar circumstances. Therefore, it was concluded that the transmittance loss or gain due to condensate at high incidence angles depended on the wettability of the cladding material.

Optical fully leaky mode characterization of a standard liquid-crystal cell

Optical excitation of fully leaky guided modes is used to characterize in detail the optical tensor profile in a liquid-crystal layer confined between two standard glass plates as for a conventional cell. The angle-dependent reflectivity and transmissivity of such a structure are explored analytically, numerically, and experimentally. By suitable choice of incident and detected polarizations it is shown possible to obtain a detailed characterization of the director profile in the cell even though the leaky optical modes lead to rather broad features in the recorded data. Using a two-prism coupling technique, matching the prisms to the glass of the cell with identical index-matching fluid, allows access to sets of both reflectivity data and transmissivity data over a sufficient range of in-plane photon wave vectors to yield unambiguous director profiles when the data are compared with modeling theory. The specific cell explored in this study contains a homogeneously aligned ferroelectric smectic material in which there is a cusped, chevron, director profile. The results presented for such a complex structure show that this powerful new form of quantified conoscopy is likely to provide the primary route forward for optical characterization of conventional cells of this nature.

Utilities for high throughput use of the single strand conformational polymorphism method: screening of 791 patients with familial hypercholesterolaemia for mutations in exon 3 of the low density lipoprotein receptor gene.

We have modified several aspects of the single strand conformational polymorphism (SSCP) method to increase the speed with which the technique can be used for mutation detection. The methods attain high resolution of small mobility differences using long (30 cm) gels and use a modified polymerase reaction to maximise detection sensitivity using a minimised quantity of 32P. By using custom cut "sharktooth" combs (4.5 mm between teeth) as the slot formers, commercially available multichannel pipettes (9 mm tip to tip) can be used to load eight or 12 samples at a time from standard microtitre plates. PCR products that have been prepared and radiolabelled using simplified protocols are loaded on to the gel, and after a precalculated time of electrophoresis another set of samples can be loaded, either with combs moved across 2.25 mm or onto the same gel tracks. The run conditions are calculated so that there is no overlap between the bands produced by the two loadings, thus doubling the amount of information that can be gained from one gel. A computer program has been developed to solve equations to determine suitable timings for repetitive loadings. Finally, a modification of the gel pouring system is described so that two gels can be poured between three standard glass plates, with both gels run simultaneously. Of the order of 1000 PCR reactions can be prepared and analysed in 24 man hours using five 40 cm x 30 cm gel tanks. The application of these techniques is described to detect SSCPs in exon 3 of the low density lipoprotein receptor (LDLR) gene in 791 patients with familial hypercholesterolaemia (FH). Eight different SSCP patterns were seen, one of which was caused by the previously described E80K mutation, which was present in 11 patients (1.4%). In total, 32 patients (4%) were identified with exon 3 mutations.