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Screening Smokes: Applications, Toxicology, Clinical Considerations, and Medical Management *
Published in Brian J. Lukey, James A. Romano, Salem Harry, Chemical Warfare Agents, 2019
Lawrence A. Bickford, Harry Salem
Chemistry and generation. Titanium tetrachloride (CAS No. 7550-45-0), also known as titanic chloride and having the military code FM, is a colorless liquid of vapor pressure 10.0 mm Hg at 208°C (Whitehead, 1983), which fumes strongly when exposed to moist air, forming a persistent dense white cloud (Lewis, 1993). The exothermic reaction products are oxychlorides and hydrogen chloride (Ballantyne, 1982) and finally, titanium hydroxide and hydrochloric acid (Lee et al., 1986). One dissemination mode is from aircraft for the production of smoke curtains extending down to ground/sea level (RAMC, 2002).
Modeling the antifouling properties of atomic layer deposition surface-modified ceramic nanofiltration membranes
Published in Biofouling, 2022
Welldone Moyo, Nhamo Chaukura, Machawe M. Motsa, Titus A. M. Msagati, Bhekie B. Mamba, Sebastiaan G. J. Heijman, Thabo T. I. Nkambule
Coating of the ceramic membrane substrate with TiO2 was conducted in a flow-type ALD reactor (TU Delft, The Netherlands). Demineralized water vapor and titanium tetrachloride (TiCI4) (Sigma-Aldrich/Fluka, The Netherlands) were the precursors for the ALD coating experiments, and nitrogen (N2) was used as the carrier gas to deliver and deposit the precursors perpendicular to the membrane surface (HiQ 5.0, The Netherlands). A digital temperature probe was used to control the ALD reactor temperature at 70 °C using an infrared lamp as a source of heat. Dry N2 was used to purge the produced hydrochloric acid (HCl), unreacted precursors and residual water (H2O) (Supplementary material, Figure S1). Three rounds of ALD coating were applied to maintain the pore size close to the uncoated membrane as possible so that the only variable for comparison was the coating on the membrane surface. Flat silicon wafers (20 mm × 20 mm) were used to determine the growth per cycle because their surfaces are terminated by the hydroxyl (OH) group, and mimic that of the ceramic membranes. The silicon wafers were placed next to the ceramic membrane in the ALD reaction chamber and the thickness of the coating on the silicon wafers was determined using an ellipsometer (M-2000F, J.A.Woollam Co. Inc., USA).
Multifunctional nanogel engineering with redox-responsive and AIEgen features for the targeted delivery of doxorubicin hydrochloride with enhanced antitumor efficiency and real-time intracellular imaging
Published in Artificial Cells, Nanomedicine, and Biotechnology, 2018
Yuwei Ma, Huiyi Zhou, Fan Hu, Zhichao Pei, Yongqian Xu, Qi Shuai
AIE molecule TPENH2 was prepared according to previous reports [46]. In brief, a certain amount of zinc powder was added to a 100 ml round-bottom flask containing 40 ml THF. The mixture was agitated in an ice bath until the temperature dropped to 0 °C. Then, titanium tetrachloride was slowly added to the reactant mixture, maintaining the temperature below 1 °C. The resulting solutions warmed to room temperature and started reflux condensation for 25 h. The mixture was cooled to 0 °C, pyridine added and stirred for 10 min. Benzophenone and 4-aminobenzophenone dissolved in 15 ml THF was slowly added to the above solution for 36 h reflux condensation. Finally, the reaction was quenched by adding 10% K2CO3. The crude extracts were obtained by extraction and TLC, and the final products were obtained as white powders by liquid chromatography (HPLC, Waters 1525) with a C18 column (5 μm particle size, 250 mm ×4.6 mm). The mobile phase consisted of methanol and water (71:29, v/v) with a flow rate of 1.0 ml/min. The detection wavelength was 254 nm and sample injected volume was 15 μl.
Suspected allergy to titanium after anterior cervical discectomy and fusion using a Zero-P device: a case report
Published in British Journal of Neurosurgery, 2023
Changgui Shi, Yanhai Xi, Bin Sun, Hailong He, Jiankun Wen, Yushan Ruan, Xiaojian Ye
In our patient, skin patch tests were performed using various reagents (e.g. compositions in the titanium and stainless-steel bars). However, the results were negative. This finding was consistent with previous case reports. Specifically, in two brothers aged 17 and 23 years,17 high fever, chest pain, and pleural effusion appeared after repair of pectus excavatum using titanium bars. There were no signs of infection. The two patients had a history of metal allergy, but skin patch tests to titanium were negative. The symptoms disappeared after the titanium bars were removed 2 years later. Similarly, in an 86-year-old male patient18 who received a pacemaker, poor healing of the wound was observed after the surgery. There was no evidence of infection. The skin patch test to titanium was negative, but the wound healing problem resolved after the removal of the titanium-containing pacemaker. The diagnosis of titanium allergy has been challenging due to its low incidence and occult manifestation. It might be misdiagnosed as other conditions (e.g. wound infection and foreign body inflammation).19 When metal allergy is suspected, skin patch tests have been commonly used. However, there has been no worldwide standard patch test reagent for titanium. A previous study examined the form and density of patch-test reagents for titanium.20 It was suggested that reagents composed of pure titanium powder and petroleum jelly were suboptimal as they are non-specific stimulants. In comparison, a titanium tetrachloride (0.1%) may be preferable. The prevalence of positive reactions against titanium reagents is very low and no patient has exhibited positive reactions only for a titanium reagent.15 Thus, skin patch tests do not always reveal a metal allergy and a negative result does not exclude the possibility.19 Collectively, both our case and the previous reports suggested that allergic reactions to titanium may occur even with negative results of the skin patch tests.