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幸运8平台彩票As the demand for solar power continues to grow, there needs to be a clear focus on different key issues in the life cycle of a solar cell. These issues are: efficiency, durability and cost. Coupling PerkinElmer’s application knowledge and experience together with our product portfolio, we can help manufacturers overcome these obstacles. At PerkinElmer, we’re taking action to ensure the quality of our environment.
There is a growing body of evidence showing that there are significant differences between some nanomaterials and their non-nanoscale counterparts. What those differences portend raises many new questions about their potential to cause harm to human health and the environment.
幸运8平台彩票The measurement of the band gap of materials is important in the semiconductor, nanomaterial and solar industries. This note demonstrates how the band gap of a material can be determined from its UV absorption spectrum.
The primary goal of this technical note is to guide the user through the accessory selection process for different specular/ diffuse samples. This will be achieved by measuring identical samples with varying contributions of diffuse and specular reflection, on three different reflection accessories, and then comparing the spectra generated.
Lead (Pb) and cadmium (Cd) are common pollutants in grains and are extremely toxic. Pb is harmful to human organs even at trace levels, and once it accumulates in the body, it causes inhibition of hemoglobin formation and neurological disorders. Cd is even classified as human carcinogen [Group 1 - according to International Agency for Research on Cancer]. It is reported that Cd leads to severe kidney problems which can be fatal and is also associated with brittle bones and liver problems. Rice, as the most widely consumed cereal grain in Asia/China, can quickly pick up Pb and Cd from toxins, pesticides and fertilizers in the soil, thereby endangering the health of millions of people through their diet. Therefore, it is extremely important to develop a simple, reliable method to monitor the levels of Pb and Cd in rice. According to Chinese national standard GB 2715-2016 Hygienic Standard for Grain, the maximum concentrations of Pb or Cd in grains must be below 0.2 mg/kg; the allowable level in the European Union is the same [EC 1881/2006]. The official technique for the determination of heavy metals in both cases is graphite furnace atomic absorption spectroscopy (GFAAS, GB/T 5009. 12-2017, GB/T 5009-2017. 15 and EN 14083:2003). Samples can be pretreated using various methods, including microwave digestion, hot block digestion, dry ashing, and hot plate digestion. It is found that these conventional digestion procedures are always complicated and time-consuming (two-four hours or even longer). Plus, conventional sample preparation techniques require large quantities of corrosive and oxidizing reagents, increasing the chance for contamination which could lead to inaccurate results. Special PTFE vessels are needed for microwave digestion; however, reusable utensils might also cause cross contamination.
Crude Palm Oil (CPO) is a raw material used in the production of margarine and other vegetable oil based food products. CPO is traded and there are quality specifications based on free fatty acids (FFAs) as well as moisture and impurities. Margarine manufacturers also want to assess the CPO’s ‘fitness for refining’ which is measured by the Deterioration of Bleachability Index (DOBI). A DOBI index of less than 1.8 indicates a poor quality oil; a DOBI index > 3 indicates a high quality oil.
Toxic elements, such as lead (Pb) and cadmium (Cd), are entering the food chain through environmental contamination. Rice, as the most widely consumed cereal grain in Asia, can quickly pick up Pb and Cd from soil, thereby seriously endangering human health through diet. These toxic element levels need to be carefully monitored. Maximum levels of Pb and Cd are strictly regulated in Asian countries, especially in China; therefore, it is extremely important to develop a simple, reliable method for trace levels of Pb and Cd in rice. The allowable maximum levels of Pb and Cd in grains in EU and China are required to be below 0.2 mg/kg (Commission Regulation EC 1881/2006 and Chinese GB 2715-2016 Hygienic Standard). Graphite furnace atomic absorption spectroscopy (GFAAS) is the officially recommended technique for detection of trace elements in various food stuffs (GB/T 5009.15-2017, GB/T 5009. 12-2017 and EN 14083:2003). Food samples are usually pretreated before GFAAS analysis using various methods: microwave digestion, hot block digestion, dry ashing, and hot plate digestion. These conventional digestion procedures are usually complicated and time-consuming (2-4 hours or longer). Plus, they require large quantities of corrosive and oxidizing reagents, increasing the chance for contamination which could lead to inaccurate results. However, fast digestion can effectively speed up the sample preparation procedure while reducing the use of corrosive reagents and the chance for contamination.
UV/Vis/NIR absorption spectroscopy has evolved to a very powerful characterization tool of carbon nanotube dispersions and has thus contributed a significant share to the insights on nanotube purity, functionalization and sorting that were elaborated the past years.
UV/Vis/NIR spectroscopy is used to study the optical properties of photovoltaic cells. The various phenomena involved (reflectance, transmittance, absorbance) are considered along with the equipment required to measure them. The study is based on a silicon cell and involves calculations to determine its selective reflectivity.
We evaluated a 3M® visible mirror film for potential use in a new curved photovoltaic module using a LAMBDA 950 spectrophotometer with an ARTA accessory. In this application, the 3M® film must transmit near-infrared photons to the underlying silicon solar cells (where they will be converted directly to electricity) while reflecting visible photons to the focus of the module where they may be absorbed by, for example a wavelength-agnostic thermal absorber used to drive a heat engine.
From the start of our busy days to the end, electricity is the life blood that keeps us going. We cook, heat, clean, light, work, communicate and are entertained all driven by electricity. The most common modes of generation are hydro, nuclear geothermal or fossil fuel powered. There is a clear need throughout the world to develop clean renewable sustainable sources of power to support growing economies and reduce our carbon footprint.
Advanced instrumentation is key to work in nano-materials. Functional tools such as optical and thermal measurement techniques allow the characterization of materials. As such, they complement imaging tools such as AFM and TEM-SEM which give spatial information on the structure of the materials. This poster presents examples of recent challenging measurements carried out in band gap analysis, plasmon resonance and polymorphic structure.