Weight reduction Clear view in wet conditions Less expensive and easy New testing methodology Polarizing sunglasses block the Analysis of dioxins in foods for composite material glare from wet surfaces and feeds using GC-MS/MS CONTENT APPLICATION Clear view in wet conditions – UV-Vis spectroscopy: Polarizing sunglasses block the glare from wet surfaces 2 What’s in the water? – Water analysis of humic acid with fluorescence spectroscopy 6 Quality control of zeolites for washing powder with EDX-8000P 9 Purification made easy – Prepara- tive purification of Ibuprofen and its related substances 12 New anti-doping method for equestrian sports 14 Less expensive with easier handling – Analysis of dioxins in foods and feeds using GC-MS/MS 16 Organic plastic in beverage bottles 22 Automotive industry – New testing methodology for weight reduction 24 Ethanol as a blending component for petrol – Determination of higher alcohols and volatile impurities by gas chromatogra- phic method 26 PRODUCTS Speeding up with Velox Core Shell – The new “Velox Core Shell“ LC columns offer more application possibilities 20 LATEST NEWS Mission for a good cause – Social Day 2018: Shimadzu Europe plants 1,500 new trees 5 Pyrolysis GC-MS user meeting – March 28, 2019 at Shimadzu’s Laboratory World Clear view in wet Duisburg, Germany 28 conditions MARKETS UV-Vis spectroscopy: Polarizing sunglasses block the Chemical, Petrochemical, Biofuel and Energy glare from wet surfaces Clinical s the days become longer, sunglasses are a common Environment A sight again. Today, there are no limits to design and color Food, Beverages, Agriculture of frame and glasses. Pharmaceutical But not all design choices are purely aesthetic: Yellow glasses Plastics and Rubber for example enhance contrast while the advantage of green Figure 1: Investigated sunglasses. Upper half: Models without polarizing filters, Automotive glass es is lower color distortion. lower half: Models with polarizing filters. SHIMADZU NEWS 1/2019 APPLICATION Polarization on a surface Light can be described as an elec- tromagnetic wave, as shown in figure 2, with propagation direc- tion C, wavelength ␭, electric field vector E and magnetic field vector B perpendicular to E. The direc- tion of the electric field vector is also described as polarization. A beam of light is composed of many such waves with the same direction of propagation. Depend - ing on the light source, the prop- erties of these photons can be very different (e.g. sunlight) or uniform Figure 2: Vector representation of an electromagnetic wave with propagation direction (e.g. laser). C, wavelength λ, electric field vector E and magnetic field vector B. The beam of light is polarized when some polarization directions are filtered out and one polariza- tion direction becomes dominant. One example is reflection on a smooth surface, as shown in figure 3. The light with polarization hor- izontal to that surface is reflected to a higher degree [1], e.g. by snow or water, but also by the optical element of a UV-Vis spec- trophotometer, such as a mirror or grating. The degree of polarization depends on the angle of incidence in both cases. Figure 3: Polarization by reflection on a surface. Light with polarization vertical This polarization of the sample to the surface enters the surface, meaning that the horizontally polarized light is beam must be compensated for reflected. The degree of polarization depends on the angle of incidence. when a sample with polarizing properties is examined. A polariz- A depolarizer (figure 4, right side) spectrophotometer was used. The er (figure 4, left side) is transpar- converts polarized light into com- baseplate of the rotating film hold- ent only to light with one polar- pletely unpolarized light [2]. er accessory was used for mount- ization direction and is used to ing the polarizer and depolarizer. Important for the necessary pro- enforce a complete polarization of Setup and samples This setup is shown in figure 5 tective functions are the shading the sample beam. By this, polar- (page 4). To compare the effects of (attenuation of the transmitted ization effects (e.g. by reflection For the measurements described polarized and unpolarized light, a light) and the wavelength range from the sample) are eliminated. here, a Shimadzu UV-3600 Plus foil polarizer (spectral range 400 - covered. Both are optimized by 700 nm) and a Hanle depolarizer the choice of base material and (spectral range 180 - 2,500 nm) coating. Quality glasses block all were used. light of wavelength 400 nm and below for complete UV protec- Two different sunglasses with po - tion. lar izing filters and two different sunglasses without polarizing fil- A special case are polarizing sun- ters were investigated. The samples glasses, promoted for watersports were carefully positioned so that and car driving purposes, just to the frame didn’t block the sample name two examples. In this case, beam. Of each sample, the trans- polarizing filters are built into the mission spectrum was measured glasses which block horizontally in the wavelength range of 400 - polarized light. Sunlight is gener- 700 nm in four different configu- ally unpolarized, but the reflec- rations: tion on a smooth surface causes a polarization horizontal to that • without any additional optics in surface. Polarizing filters are sup- the light path posed to protect the user from Figure 4: Polarizer (left) and depolarizer (right). The line on the polarizer mount indicates • with unpolarized light (depolar- this glare. the polarization direction of the transmitted light. izer in position A) SHIMADZU NEWS 1/2019 3 APPLICATION • with vertical polarized light influence on the measurements. (polarizer set to 0° in position This is different to the spectra of A) the black and multicolored sun- • with horizontal polarized light glasses. As expected from sun- (polarizer set to 90° in position glasses promoted for watersports, A). the transmission for horizontally polarized light is very low. The Polarizing filters for black sunglasses show transmis- selective absorption sion values of around 20 % for vertical polarized light in this Figure 6 shows the transmission measurement range, but only 10 % spectra of the sunglasses described for unpolarized light and less than above. The samples are labelled by 5 % for horizontal polarized light. their glass color as orange (upper left), green (upper right), black This effect is weaker with the (lower left) and multicolored (low - multicolored sunglasses. The spec- er right). The spectra are arranged tra measured with unpolarized analog to the pho tos of figure 1 and vertically polarized light are (page 2). nearly congruent. The attenuation of horizontally polarized light is Only the spectra of polarizing still remarkable though. The best glasses without additional optics attenuation is observed in the show peaks at 470, 580 and 665 nm. spectral range of 500 - 620 nm, Transmission in these measure- while the black sunglasses show ments is also below the values an even attenuation over the whole measured for the same glasses spectral range up to 650 nm. with a depolarizer in the light Figure 5: Experimental setup. A: Mounting position for polarizer or depolarizer, path. This shows that the sample B: Sunglasses, C: Sample beam, D: Reference beam. Conclusion beam is horizontally polarized to some degree. As the degree of rectly dependent on the wave- For the orange and green sun- Many projects in the optic indus- polarization depends on the angle length. The spectra measured glasses, all four spectra are con- try are concerned with polarized of incidence to the polarizing ele- with out depolarizer are influenced gruent. The polarization of the light. Using a depolarizer will ment, this absorption is only indi- by such polarization effects. sample beam does not have any ensure that the sample is irradiat- ed with completely unpolarized light. Measurement artifacts are Sunglasses Orange Sunglasses Green therefore avoided and the true 100 40 properties of polarizing samples are elucidated. 80 60 Literature 20 40 [1] https://en.wikipedia.org/wiki/ Polarization_(waves) 20 Transmission [%T] Transmission [%T] Transmission [2] https://en.wikipedia.org/wiki/Depolarizer_ 0 0 (optics) 400 500 600 700 400 500 600 700 Wavelength [nm] Wavelength [nm] Further information on this article: Sunglasses Black Sunglasses Multicolored • Application: 100 40 shimnet.shimadzu. local/product/Spectro/ 40 Spectro_UV/Application_Notes/SCA- 100-022_Sunglasses.pdf 20 20 Transmission [%] Transmission [%] Transmission 0 0 400 500 600 700 400 500 600 700 Wavelength [nm] Wavelength [nm] ––– Normal ––– Unpolarized ––– Vertical polarized ––– Horizontal polarized Figure 6: Transmission spectra of the four sunglasses from figure 1 (page 2), each measured in four configurations and in the spectral range of 400 - 700 nm. Upper half: Samples without polarizing filters, lower half: Samples with polarizing filters. 4 SHIMADZU NEWS 1/2019 LATEST NEWS Mission for a good cause Social Day 2018: Shimadzu Europe plants 1,500 new trees he social day, at which land is part of the Duisburg them grows best in the first 20 to which secure the best spot in the Shimadzu employees sup- Sechs-Seen-Platte (Six Lakes Re- 30 years. This replicates nature sun over the longest period, T port social projects, has gion), a recreational area with a that produces an unimaginably receiving the most sunlight in the become a tradition within the network of hiking trails of 18 kilo- large number of seedling offspring long term. company since 2013. Once again, meters. by natural seeding from the moth- volunteers have been actively er trees, which evolve over the Social Responsibility involved in their community and The two-three-year-old trees with years so that only a few trees in December 2018 helped to refor- a size of about 1.50 m were plant- remain and their number contin- ‘Realizing wishes for the well- est an area in the city forest of ed relatively densely, so they can ues to reduce further as they being of mankind and the Earth’ Duisburg with 1,500 new trees.