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UV Reflectance Photography
Published in Adrian Davies, Digital Ultraviolet and Infrared Photography, 2017
The basic requirement for a UV-transmitting filter is for it to absorb all visible light and IR wavelengths, and just transmit UV wavelengths. The traditional filter used for analogue UV reflectance photography was the Kodak Wratten 18A Wood’s Glass filter (other companies had their own equivalents; for example, Ilford 828, Schott UG 11, Chance OX-1). These filters were usually supplied in square blocks of glass from 2mm to 5mm thick (gelatin, commonly used at the time for making photographic filters, could not be used for UV work as gelatin absorbs UV wavelengths). Wood’s glass filters are composed of special barium-sodium-silicate glass incorporating about 9 per cent nickel oxide. They have good UV transmission (from 320nm to 400nm, peaking at 365nm). However, they also transmitted a small but significant amount of IR radiation. When used with monochrome film, this IR ‘leakage’ was of no consequence, as panchromatic film is not sensitive to IR. However, digital sensors on cameras converted to ‘full spectrum’ are highly sensitive to IR, and this would need to be filtered out with an IR-absorbing filter such as a hot mirror filter.
Miscellaneous chemicals *
Published in Bev-Lorraine True, Robert H. Dreisbach, Dreisbach’s HANDBOOK of POISONING, 2001
Bev-Lorraine True, Robert H. Dreisbach
The anionic household detergents (hand dishwashing liquids, hair shampoo) are sulfonated hydrocarbons or phosphorylated hydrocarbons. Powdered, flake, or bar soaps are made of sodium, potassium, or ammonium salts of fatty acids. Laundry compounds (All, Tide, Cheer, etc.) have added water softeners such as sodium phosphate, sodium carbonate, or sodium silicate (see p. 257).
Boron, Manganese, Molybdenum, Nickel, Silicon and Vanadium
Published in Judy A. Driskell, Ira Wolinsky, Sports Nutrition, 2005
Silicon has long been suspected to be a beneficial bioactive, if not essential, element for humans. According to a review by Becker et al.,155 Louis Pasteur predicted that silicon would be found to be an important therapeutic substance for many diseases. At the beginning of the 20th century, French and German reports suggested that Pasteur’s prediction would become fact. These reports described therapeutic successes in treating numerous diseases, including atherosclerosis, hypertension and dermatitis with sodium silicate, simple organic silicon compounds or tea made from the silicon-rich horsetail plant.155,156 Also, there was some thought that silicon was essential because, according to the review by Schwarz,156 an article in 1930 stated that silicic acid was recognized as a normal constituent of the human organism, primarily of connective tissue, and the opinion was stated that “silicic acid is for connective tissue approximately of the same importance as iron for red blood cells, namely that it is simultaneously a stimulant for its formation as well as a building material for this tissue.” However, by 1935, silicon in medicine and the concept of silicon’s essentiality faded into obscurity as a consequence of some therapeutic failures and inadequate evidence for silicon’s being biologically active. For the next 40 years, silicon as consumed in the diet was generally considered a biologically inert, harmless, nonessential element for living organisms except for some lower forms of life (silicate bacteria, diatoms, radiolarians and sponges).
Preparation and characterization of co-processed starch/MCC/chitin hydrophilic polymers onto magnesium silicate
Published in Pharmaceutical Development and Technology, 2019
Shereen M. Assaf, Mai Subhi Khanfar, Ahmed Bassam Farhan, Iyad Said Rashid, Adnan Ali Badwan
Commercial maize starch was purchased from Beijing Quanfeng Starch Company (China). Chitin, potassium dihydrogen phosphate and dipotassium hydrogen phosphate anhydrous were obtained from BICHEM (Shanghai, China). Microcrystalline cellulose, MCC (Avicel PH 200) was obtained from FMC Biopolymer (Philadelphia, PA, USA). Sodium silicate (Na2SiO3.5H2O) was obtained from BDH (Poole, England). Sunset yellow solution and Sodium chloride were obtained from Analytical Rasayan Laboratory (India). Ibuprofen powder and Mg chloride (MgCl2.6H2O) were obtained from Sigma (St. Louis, MO). Commercial ibuprofen immediate-release tablets (400 mg, Remofen®, Hikma Pharmaceuticals PLC, Jordan) were purchased from the local market in Jordan. Sodium hydroxide was obtained from Frutarom LTD (UK). Potassium nitrate and Mg nitrate (Mg(NO3)2.6H2O) were obtained from Scharlau (Spain). Water used in this work was distilled and deionized. All reagents used were of analytical grade. All chemicals were used as supplied.
Preparation of mesoporous silica microparticles by sol–gel/emulsion route for protein release
Published in Pharmaceutical Development and Technology, 2019
Mariya I. Vlasenkova, Ekaterina S. Dolinina, Elena V. Parfenyuk
However, it should be noted that a majority of enzymes have relatively high structure stability, and according to the classification introduced by Norde (1992), they can be related to ‘hard’ proteins. Encapsulation of ‘soft’ proteins such as albumins (Norde 1992) without loss of their native conformation is more difficult task. Fournier and McGrath (2011) reported direct encapsulation of bovine serum albumin (BSA) and lysozyme into microporous silica capsules using a W/O emulsion. The studies of the protein conformations in the synthesized composites by Fourier transform infrared (FTIR) spectroscopy showed that the α-helix content for both proteins was decreased. Fujiwara et al. (2006) reported the encapsulation of DNA and BSA into hollow silica spheres using more complicated W/O/W emulsion. Sodium silicate was used as silica precursor. The main advantage of the method proposed by Fujiwara et al. is direct synthesis allowing simple and quick isolation of the prepared-loaded microcapsules using the second aqueous phase, salt solution, as precipitant. However, the authors noted that because the protein size was larger than the pores of microcapsule shells, the protein cannot be released from the microcapsules. Meanwhile, BSA released from the destructed capsules showed only some structural alterations, i.e. mainly retained its native structure.
Cytotoxicity, dose-enhancement and radiosensitization of glioblastoma cells with rare earth nanoparticles
Published in Artificial Cells, Nanomedicine, and Biotechnology, 2019
Victor M. Lu, Felicity Crawshay-Williams, Benjamin White, Amy Elliot, Mark A. Hill, Helen E. Townley
Silica coating can sometimes alter the way in which particles aggregate and interact with cells. To enable a pairwise comparison Nd2O3 nanoparticles were coated with silica. The Nd2O3 nanoparticles were resuspended in 200 ml distilled water (pH 4.5) [Solution I]. Next, 3-Maercaptoethnaol-trimethoxy-silane (1.89 ml; Sigma-Aldrich) was added to 50 ml distilled water [Solution II]. Twenty millilitres of solution II were then added to solution I and stirred. After 1 h, sodium silicate (40 ml; Sigma-Aldrich) was added. Samples were removed after 10 min, centrifuged immediately and washed with distilled water three times.