| 1 | Evaluation of the adsorption potential of titanium dioxide nanoparticles for arsenic removal显示文摘The adsorption potential of titanium dioxide(TiO2) nanoparticles for removing arsenic from drinking water was evaluated.Pure and iron-doped TiO2 particles are synthesized via sol-gel method.The synthesized TiO2 nanoparticles were then immobilized on ordinary sand for adsorption studies.Adsorption isotherms were conducted on the synthesized nanoparticles as well as the sand coated with TiO2 nanoparticles under varying conditions of air and light,namely,the air-sunlight(A-SL),air-light(AL),air-dark(AD) and nitrogen-dark(ND).X-ray diffraction(XRD) analysis showed that the pure and iron-doped TiO2 nanoparticles were in 100% anatase crystalline phase with crystal sizes of 108 and 65 nm,respectively.Adsorption of arsenic on the three adsorbents was non-linear that could be described by the Freundlich and Langmuir adsorption models.Iron doping enhanced the adsorption capacity of TiO2 nanoparticles by arresting the grain growth and making it visible light responsive resulting in a higher affnity for arsenic.Similarly,the arsenic removal by adsorption on the sand coated with TiO2 nanoparticles was the highest among the three types of sand used.In all cases,As(V) was adsorbed more compared with As(Ⅲ).The solution pH appeared to be the most important factor in controlling the amount of arsenic adsorbed. | NABI Deedar ASLAM Irfan QAZI Ishtiaq A | 2009 | Journal of Environmental Sciences2009，21，3： | 14 |
| 5 | Assessment of sub-milli-sievert abdominal computed tomography with iterative reconstruction techniques of different vendors显示文摘AIM: To assess diagnostic image quality of reduced dose(RD) abdominal computed tomography(CT) with 9 iterative reconstruction techniques(IRTs) from 4 different vendors to the standard of care(SD) CT.METHODS: In an Institutional Review Board approved study, 66 patients(mean age 60 ± 13 years, 44 men, and 22 women) undergoing routine abdomen CT on multi-detector CT(MDCT) scanners from vendors A, B, and C(≥ 64 row CT scanners)(22 patients each) gave written informed consent for acquisition of an additional RD CT series. Sinogram data of RD CT was reconstructed with two vendor-specific and a vendor-neutral IRTs(A-1, A-2, A-3; B-1, B-2, B-3; and C-1, C-2, C-3) and SD CT series with filtered back projection. Subjective image evaluation was performed by two radiologists for each SD and RD CT series blinded and independently. All RD CT series(198) were assessed first followed by SD CT series(66). Objective image noise was measured for SD and RD CT series. Data were analyzed by Wilcoxon signed rank, kappa, and analysis of variance tests.RESULTS: There were 13/50, 18/57 and 9/40 missed lesions(size 2-7 mm) on RD CT for vendor A, B, and C, respectively. Missed lesions includes liver cysts, kidney cysts and stone, gall stone, fatty liver, and pancreatitis. There were also 5, 4, and 4 pseudo lesions(size 2-3 mm) on RD CT for vendor A, B, and C, respectively. Lesions conspicuity was sufficient for clinical diagnostic performance for 6/24(RD-A-1), 10/24(RD-A-2), and 7/24(RD-A-3) lesions for vendor A; 5/26(RD-B-1), 6/26(RD-B-2), and 7/26(RD-B-3) lesions for vendor B; and 4/20(RD-C-1) 6/20(RD-C-2), and 10/20(RD-C-3) lesions for vendor C(P = 0.9). Mean objective image noise in liver was significantly lower for RD A-1 compared to both RD A-2 and RD A-3 images(P < 0.001). Similarly, mean objective image noise lower for RD B-2(compared to RD B-1, RD B-3) and RD C-3(compared to RD C-1 and C-2)(P = 0.016).CONCLUSION: Regardless of IRTs and MDCT vendors, abdominal CT acquired at mean CT dose index volume 1.3 m Gy is not sufficient to retain clinical diagnostic performance. | Atul Padole Nisha Sainani Diego Lira Ranish Deedar Ali Khawaja Sarvenaz Pourjabbar Roberto Lo Gullo Alexi Otrakji Mannudeep K Kalra | 2016 | World Journal of Radiology2016，8，6： | 1 |
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