ABSTRACT
Coronavirus 19 (COVID-19) is an extremely transmittable microbial infection that has emerged in Wuhan (China) in late 2019, leading to severe acute respiratory syndrome coronavirus 2 syndrome, and caused a pandemic all over the globe. This study is a systematic review of all 927 clinical trial studies performed worldwide from the beginning of the COVID-19 mysterious pandemic in China. These researches have registered in different databases. According to the best of our knowledge, China (74.82%), the United States (4.49%), and France (2.72%) have the most significant number of clinical trials, respectively. Clinical trials can be randomized or nonrandomized. Due to our results, 32.58% of studies were randomized, and 7.12% were not randomized. Most of the studies were open-labeled studies (22.44%), and double-blinded (4.42%) and quadruple blinded (2.48%) studies stand in second and third place regarding the number of trials, respectively. The direction and quantity of clinical trials attempted to identify a possible cure for COVID-19 demonstrates the depth of this crisis. As we are writing this article, a significant international endeavor will find a cure or vaccine for containing this devastating and mysterious disease.
ABSTRACT
Potassium-decyl-18-crown-6 was used as a highly selective and efficient carrier for uphill transport of silver as AgBr2-complex ion through a chloroform bulk liquid membrane. When thiosulfate anion was used as a metal ion acceptor in the receiving phase the amounts of silver transported across the liquid membrane after 120 and 180 min were 87.0 +/- 1.8% and 96.0 +/- 1.9%, respectively. The selectivity and efficiency of silver transport from aqueous solution containing Cu2+, Zn2+, Ni2+, Cd2+, Pb2+ and Fe3+ ions were investigated. In the presence of EDTA at pH = 4 as suitable masking agent in the source phase, the interfering effects of Pb2+ and Fe3+ ions were diminished drastically.
