ABSTRACT
A novel environmentally-friendly porous hydrogel adsorbent (GHPN) is firstly designed and prepared using dextran, phosphate, and calcium hydroxide for the adsorption of Be(II). GHPN shows good adsorption selectivity for Be(II) (Kdâ¯=â¯1.53â¯×â¯104â¯mL/g). According the adsorption kinetics and thermodynamics, the theoretical adsorption capacity of GHPN to Be(II) is 43.75â¯mg/g (35⯰C, pHâ¯=â¯6.5), indicating a spontaneous exothermic reaction. After being reused for 5â¯cycles, the adsorption and desorption efficiencies of Be(II) with GHPN are obtained to be more than 80â¯%, showing acceptable recycling performance. Both of the characterizations and theoretical calculations indicate that the phosphate group, hydroxyl group, and amino group own the affinity to form stable complexes with Be(II). Benefiting from the introduction of phosphate and amino, the adsorption effect of the hydrogel adsorbent on Be(II) can be greatly improved, and surface precipitation, complexation, and ligand exchange are the dominant mechanisms of beryllium adsorption. The results suggest that GHPN has great potential to be utilized as an eco-friendly and useful adsorbent of Be(II) from aqueous solution.
Subject(s)
Dextrans , Hydrogels , Phosphates , Water Pollutants, Chemical , Water Purification , Adsorption , Dextrans/chemistry , Porosity , Phosphates/chemistry , Water Pollutants, Chemical/chemistry , Water Pollutants, Chemical/isolation & purification , Kinetics , Water Purification/methods , Hydrogels/chemistry , Thermodynamics , Hydrogen-Ion Concentration , Solutions , Water/chemistrySubject(s)
Platelet Aggregation Inhibitors , Warfarin , Anticoagulants , Epistaxis , Factor Xa Inhibitors , Fibrinolytic Agents , HumansABSTRACT
PURPOSE: The purpose of the study was to define the frequency of an inferomedial patellar protuberance in patients presenting to a specialist Patella Clinic and to characterise the clinical and radiological features as well the association between the inferomedial patellar protuberance and the medial patellar ossicle. METHODS: A cohort of 163 patients (166 knees) was reviewed from a prospectively collected clinical database and radiological imaging. This included a record of patellar tracking. RESULTS: An inferomedial patellar protuberance was found in 62 (37 %) knees. A medial patellar ossicle was noted in 56 (34 %) knees. In all, an inferomedial patellar protuberance or medial patellar ossicle or both was found in 90 (54 %) knees. The association between inferomedial patellar protuberance and significant trochlear dysplasia was highly significant (p = 0.01), but not for the medial patellar ossicle (n.s.). The presence of an inferomedial patellar protuberance was significantly less likely in patients with hypermobility syndrome (p = 0.001); however, there was no significant association between hypermobility syndrome and medial patellar ossicle (n.s.), or the presence of either or both an inferomedial patellar protuberance and medial patellar ossicle (n.s.). All patients with a clunk at 20°-30° flexion had significant trochlear dysplasia and an inferomedial patellar protuberance. CONCLUSION: Radiological changes consistent with an inferomedial patellar protuberance were found in about one-third of patients presenting to a specialist Patella Clinic. Patellar maltracking and a clunk at 20°-30° flexion are associated with significant trochlear dysplasia plus an inferomedial patellar protuberance. If undertaking an operative correction, both deformities should be considered in order to avoid joint incongruity. LEVEL OF EVIDENCE: III.
