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result sql = The role of natural purified humic acids in modifying mercury accessibility in water and soil.
The role of natural purified humic acids in modifying mercury accessibility in water and soil.
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char = s;code = 115
char = ;code = 32
char = u;code = 117
char = s;code = 115
char = e;code = 101
char = d;code = 100
char = ;code = 32
char = i;code = 105
char = n;code = 110
char = ;code = 32
char = s;code = 115
char = o;code = 111
char = l;code = 108
char = u;code = 117
char = t;code = 116
char = i;code = 105
char = o;code = 111
char = n;code = 110
char = s;code = 115
char = ;code = 32
char = a;code = 97
char = n;code = 110
char = d;code = 100
char = ;code = 32
char = s;code = 115
char = o;code = 111
char = i;code = 105
char = l;code = 108
char = s;code = 115
char = .;code = 46
char = ;code = 32
char = T;code = 84
char = h;code = 104
char = e;code = 101
char = ;code = 32
char = D;code = 68
char = G;code = 71
char = T;code = 84
char = ;code = 32
char = m;code = 109
char = e;code = 101
char = a;code = 97
char = s;code = 115
char = u;code = 117
char = r;code = 114
char = e;code = 101
char = m;code = 109
char = e;code = 101
char = n;code = 110
char = t;code = 116
char = s;code = 115
char = ;code = 32
char = i;code = 105
char = n;code = 110
char = ;code = 32
char = s;code = 115
char = o;code = 111
char = l;code = 108
char = u;code = 117
char = t;code = 116
char = i;code = 105
char = o;code = 111
char = n;code = 110
char = ,;code = 44
char = ;code = 32
char = t;code = 116
char = o;code = 111
char = g;code = 103
char = e;code = 101
char = t;code = 116
char = h;code = 104
char = e;code = 101
char = r;code = 114
char = ;code = 32
char = w;code = 119
char = i;code = 105
char = t;code = 116
char = h;code = 104
char = ;code = 32
char = u;code = 117
char = l;code = 108
char = t;code = 116
char = r;code = 114
char = a;code = 97
char = f;code = 102
char = i;code = 105
char = l;code = 108
char = t;code = 116
char = r;code = 114
char = a;code = 97
char = t;code = 116
char = i;code = 105
char = o;code = 111
char = n;code = 110
char = ,;code = 44
char = ;code = 32
char = a;code = 97
char = l;code = 108
char = l;code = 108
char = o;code = 111
char = w;code = 119
char = e;code = 101
char = d;code = 100
char = ;code = 32
char = e;code = 101
char = s;code = 115
char = t;code = 116
char = i;code = 105
char = m;code = 109
char = a;code = 97
char = t;code = 116
char = i;code = 105
char = o;code = 111
char = n;code = 110
char = ;code = 32
char = o;code = 111
char = f;code = 102
char = ;code = 32
char = t;code = 116
char = h;code = 104
char = e;code = 101
char = ;code = 32
char = l;code = 108
char = a;code = 97
char = b;code = 98
char = i;code = 105
char = l;code = 108
char = i;code = 105
char = t;code = 116
char = y;code = 121
char = ;code = 32
char = o;code = 111
char = f;code = 102
char = ;code = 32
char = H;code = 72
char = g;code = 103
char = -;code = 45
char = H;code = 72
char = A;code = 65
char = ;code = 32
char = c;code = 99
char = o;code = 111
char = m;code = 109
char = p;code = 112
char = l;code = 108
char = e;code = 101
char = x;code = 120
char = e;code = 101
char = s;code = 115
char = .;code = 46
char = ;code = 32
char = U;code = 85
char = l;code = 108
char = t;code = 116
char = r;code = 114
char = a;code = 97
char = f;code = 102
char = i;code = 105
char = l;code = 108
char = t;code = 116
char = r;code = 114
char = a;code = 97
char = t;code = 116
char = i;code = 105
char = o;code = 111
char = n;code = 110
char = ;code = 32
char = r;code = 114
char = e;code = 101
char = s;code = 115
char = u;code = 117
char = l;code = 108
char = t;code = 116
char = s;code = 115
char = ;code = 32
char = w;code = 119
char = e;code = 101
char = r;code = 114
char = e;code = 101
char = ;code = 32
char = a;code = 97
char = l;code = 108
char = s;code = 115
char = o;code = 111
char = ;code = 32
char = c;code = 99
char = o;code = 111
char = m;code = 109
char = p;code = 112
char = a;code = 97
char = r;code = 114
char = e;code = 101
char = d;code = 100
char = ;code = 32
char = w;code = 119
char = i;code = 105
char = t;code = 116
char = h;code = 104
char = ;code = 32
char = p;code = 112
char = r;code = 114
char = e;code = 101
char = d;code = 100
char = i;code = 105
char = c;code = 99
char = t;code = 116
char = i;code = 105
char = o;code = 111
char = n;code = 110
char = s;code = 115
char = ;code = 32
char = m;code = 109
char = a;code = 97
char = d;code = 100
char = e;code = 101
char = ;code = 32
char = b;code = 98
char = y;code = 121
char = ;code = 32
char = t;code = 116
char = h;code = 104
char = e;code = 101
char = ;code = 32
char = w;code = 119
char = i;code = 105
char = n;code = 110
char = d;code = 100
char = e;code = 101
char = r;code = 114
char = m;code = 109
char = e;code = 101
char = r;code = 114
char = e;code = 101
char = ;code = 32
char = h;code = 104
char = u;code = 117
char = m;code = 109
char = i;code = 105
char = c;code = 99
char = -;code = 45
char = a;code = 97
char = q;code = 113
char = u;code = 117
char = e;code = 101
char = o;code = 111
char = u;code = 117
char = s;code = 115
char = ;code = 32
char = m;code = 109
char = o;code = 111
char = d;code = 100
char = e;code = 101
char = l;code = 108
char = ;code = 32
char = (;code = 40
char = W;code = 87
char = H;code = 72
char = A;code = 65
char = M;code = 77
char = );code = 41
char = .;code = 46
char = ;code = 32
char = A;code = 65
char = c;code = 99
char = c;code = 99
char = o;code = 111
char = r;code = 114
char = d;code = 100
char = i;code = 105
char = n;code = 110
char = g;code = 103
char = ;code = 32
char = t;code = 116
char = o;code = 111
char = ;code = 32
char = b;code = 98
char = o;code = 111
char = t;code = 116
char = h;code = 104
char = ;code = 32
char = t;code = 116
char = h;code = 104
char = e;code = 101
char = s;code = 115
char = e;code = 101
char = ;code = 32
char = d;code = 100
char = i;code = 105
char = f;code = 102
char = f;code = 102
char = e;code = 101
char = r;code = 114
char = e;code = 101
char = n;code = 110
char = t;code = 116
char = ;code = 32
char = a;code = 97
char = p;code = 112
char = p;code = 112
char = r;code = 114
char = o;code = 111
char = a;code = 97
char = c;code = 99
char = h;code = 104
char = e;code = 101
char = s;code = 115
char = ,;code = 44
char = ;code = 32
char = H;code = 72
char = g;code = 103
char = (;code = 40
char = 2;code = 50
char = +;code = 43
char = );code = 41
char = ;code = 32
char = r;code = 114
char = e;code = 101
char = s;code = 115
char = u;code = 117
char = l;code = 108
char = t;code = 116
char = e;code = 101
char = d;code = 100
char = ;code = 32
char = n;code = 110
char = e;code = 101
char = a;code = 97
char = r;code = 114
char = l;code = 108
char = y;code = 121
char = ;code = 32
char = 1;code = 49
char = 0;code = 48
char = 0;code = 48
char = %;code = 37
char = ;code = 32
char = c;code = 99
char = o;code = 111
char = m;code = 109
char = p;code = 112
char = l;code = 108
char = e;code = 101
char = x;code = 120
char = e;code = 101
char = d;code = 100
char = ;code = 32
char = b;code = 98
char = y;code = 121
char = ;code = 32
char = H;code = 72
char = A;code = 65
char = s;code = 115
char = ,;code = 44
char = ;code = 32
char = w;code = 119
char = h;code = 104
char = e;code = 101
char = r;code = 114
char = e;code = 101
char = a;code = 97
char = s;code = 115
char = ;code = 32
char = r;code = 114
char = e;code = 101
char = s;code = 115
char = u;code = 117
char = l;code = 108
char = t;code = 116
char = s;code = 115
char = ;code = 32
char = f;code = 102
char = r;code = 114
char = o;code = 111
char = m;code = 109
char = ;code = 32
char = u;code = 117
char = l;code = 108
char = t;code = 116
char = r;code = 114
char = a;code = 97
char = f;code = 102
char = i;code = 105
char = l;code = 108
char = t;code = 116
char = r;code = 114
char = a;code = 97
char = t;code = 116
char = i;code = 105
char = o;code = 111
char = n;code = 110
char = ;code = 32
char = s;code = 115
char = h;code = 104
char = o;code = 111
char = w;code = 119
char = e;code = 101
char = d;code = 100
char = ;code = 32
char = t;code = 116
char = h;code = 104
char = a;code = 97
char = t;code = 116
char = ;code = 32
char = 3;code = 51
char = 2;code = 50
char = ;code = 32
char = t;code = 116
char = o;code = 111
char = ;code = 32
char = 7;code = 55
char = 2;code = 50
char = %;code = 37
char = ;code = 32
char = o;code = 111
char = f;code = 102
char = ;code = 32
char = t;code = 116
char = h;code = 104
char = e;code = 101
char = ;code = 32
char = C;code = 67
char = H;code = 72
char = (;code = 40
char = 3;code = 51
char = );code = 41
char = H;code = 72
char = g;code = 103
char = (;code = 40
char = +;code = 43
char = );code = 41
char = ;code = 32
char = w;code = 119
char = a;code = 97
char = s;code = 115
char = ;code = 32
char = b;code = 98
char = o;code = 111
char = u;code = 117
char = n;code = 110
char = d;code = 100
char = ;code = 32
char = t;code = 116
char = o;code = 111
char = ;code = 32
char = t;code = 116
char = h;code = 104
char = e;code = 101
char = ;code = 32
char = H;code = 72
char = A;code = 65
char = s;code = 115
char = ,;code = 44
char = ;code = 32
char = w;code = 119
char = i;code = 105
char = t;code = 116
char = h;code = 104
char = ;code = 32
char = h;code = 104
char = i;code = 105
char = g;code = 103
char = h;code = 104
char = e;code = 101
char = r;code = 114
char = ;code = 32
char = v;code = 118
char = a;code = 97
char = l;code = 108
char = u;code = 117
char = e;code = 101
char = s;code = 115
char = ;code = 32
char = f;code = 102
char = o;code = 111
char = r;code = 114
char = ;code = 32
char = c;code = 99
char = o;code = 111
char = m;code = 109
char = p;code = 112
char = o;code = 111
char = s;code = 115
char = t;code = 116
char = ;code = 32
char = a;code = 97
char = n;code = 110
char = d;code = 100
char = ;code = 32
char = l;code = 108
char = o;code = 111
char = w;code = 119
char = e;code = 101
char = r;code = 114
char = ;code = 32
char = v;code = 118
char = a;code = 97
char = l;code = 108
char = u;code = 117
char = e;code = 101
char = s;code = 115
char = ;code = 32
char = f;code = 102
char = o;code = 111
char = r;code = 114
char = ;code = 32
char = f;code = 102
char = o;code = 111
char = r;code = 114
char = e;code = 101
char = s;code = 115
char = t;code = 116
char = ;code = 32
char = a;code = 97
char = n;code = 110
char = d;code = 100
char = ;code = 32
char = A;code = 65
char = l;code = 108
char = d;code = 100
char = r;code = 114
char = i;code = 105
char = c;code = 99
char = h;code = 104
char = ;code = 32
char = H;code = 72
char = A;code = 65
char = .;code = 46
char = ;code = 32
char = T;code = 84
char = h;code = 104
char = e;code = 101
char = ;code = 32
char = D;code = 68
char = G;code = 71
char = T;code = 84
char = -;code = 45
char = m;code = 109
char = e;code = 101
char = a;code = 97
char = s;code = 115
char = u;code = 117
char = r;code = 114
char = e;code = 101
char = d;code = 100
char = ;code = 32
char = m;code = 109
char = e;code = 101
char = r;code = 114
char = c;code = 99
char = u;code = 117
char = r;code = 114
char = y;code = 121
char = ;code = 32
char = i;code = 105
char = n;code = 110
char = ;code = 32
char = s;code = 115
char = o;code = 111
char = i;code = 105
char = l;code = 108
char = s;code = 115
char = ;code = 32
char = w;code = 119
char = a;code = 97
char = s;code = 115
char = ;code = 32
char = b;code = 98
char = e;code = 101
char = l;code = 108
char = o;code = 111
char = w;code = 119
char = ;code = 32
char = 0;code = 48
char = .;code = 46
char = 2;code = 50
char = 0;code = 48
char = ;code = 32
char = m;code = 109
char = i;code = 105
char = c;code = 99
char = r;code = 114
char = o;code = 111
char = g;code = 103
char = ;code = 32
char = L;code = 76
char = (;code = 40
char = -;code = 45
char = 1;code = 49
char = );code = 41
char = ,;code = 44
char = ;code = 32
char = i;code = 105
char = r;code = 114
char = r;code = 114
char = e;code = 101
char = s;code = 115
char = p;code = 112
char = e;code = 101
char = c;code = 99
char = t;code = 116
char = i;code = 105
char = v;code = 118
char = e;code = 101
char = ;code = 32
char = o;code = 111
char = f;code = 102
char = ;code = 32
char = t;code = 116
char = h;code = 104
char = e;code = 101
char = ;code = 32
char = e;code = 101
char = x;code = 120
char = t;code = 116
char = e;code = 101
char = n;code = 110
char = t;code = 116
char = ;code = 32
char = o;code = 111
char = f;code = 102
char = ;code = 32
char = t;code = 116
char = h;code = 104
char = e;code = 101
char = ;code = 32
char = c;code = 99
char = o;code = 111
char = n;code = 110
char = t;code = 116
char = a;code = 97
char = m;code = 109
char = i;code = 105
char = n;code = 110
char = a;code = 97
char = t;code = 116
char = i;code = 105
char = o;code = 111
char = n;code = 110
char = .;code = 46
char = ;code = 32
char = A;code = 65
char = d;code = 100
char = d;code = 100
char = i;code = 105
char = t;code = 116
char = i;code = 105
char = o;code = 111
char = n;code = 110
char = ;code = 32
char = o;code = 111
char = f;code = 102
char = ;code = 32
char = H;code = 72
char = A;code = 65
char = ;code = 32
char = i;code = 105
char = n;code = 110
char = c;code = 99
char = r;code = 114
char = e;code = 101
char = a;code = 97
char = s;code = 115
char = e;code = 101
char = d;code = 100
char = ;code = 32
char = t;code = 116
char = h;code = 104
char = e;code = 101
char = ;code = 32
char = c;code = 99
char = o;code = 111
char = n;code = 110
char = c;code = 99
char = e;code = 101
char = n;code = 110
char = t;code = 116
char = r;code = 114
char = a;code = 97
char = t;code = 116
char = i;code = 105
char = o;code = 111
char = n;code = 110
char = ;code = 32
char = o;code = 111
char = f;code = 102
char = ;code = 32
char = D;code = 68
char = G;code = 71
char = T;code = 84
char = -;code = 45
char = m;code = 109
char = e;code = 101
char = a;code = 97
char = s;code = 115
char = u;code = 117
char = r;code = 114
char = e;code = 101
char = d;code = 100
char = ;code = 32
char = m;code = 109
char = e;code = 101
char = r;code = 114
char = c;code = 99
char = u;code = 117
char = r;code = 114
char = y;code = 121
char = ;code = 32
char = i;code = 105
char = n;code = 110
char = ;code = 32
char = s;code = 115
char = o;code = 111
char = i;code = 105
char = l;code = 108
char = ;code = 32
char = s;code = 115
char = o;code = 111
char = l;code = 108
char = u;code = 117
char = t;code = 116
char = i;code = 105
char = o;code = 111
char = n;code = 110
char = ;code = 32
char = u;code = 117
char = p;code = 112
char = ;code = 32
char = t;code = 116
char = o;code = 111
char = ;code = 32
char = 1;code = 49
char = 0;code = 48
char = 0;code = 48
char = -;code = 45
char = f;code = 102
char = o;code = 111
char = l;code = 108
char = d;code = 100
char = ;code = 32
char = i;code = 105
char = n;code = 110
char = ;code = 32
char = t;code = 116
char = h;code = 104
char = e;code = 101
char = ;code = 32
char = c;code = 99
char = o;code = 111
char = n;code = 110
char = t;code = 116
char = a;code = 97
char = m;code = 109
char = i;code = 105
char = n;code = 110
char = a;code = 97
char = t;code = 116
char = e;code = 101
char = d;code = 100
char = ;code = 32
char = s;code = 115
char = o;code = 111
char = i;code = 105
char = l;code = 108
char = ;code = 32
char = a;code = 97
char = n;code = 110
char = d;code = 100
char = ;code = 32
char = u;code = 117
char = p;code = 112
char = ;code = 32
char = t;code = 116
char = o;code = 111
char = ;code = 32
char = 3;code = 51
char = 0;code = 48
char = -;code = 45
char = f;code = 102
char = o;code = 111
char = l;code = 108
char = d;code = 100
char = ;code = 32
char = i;code = 105
char = n;code = 110
char = ;code = 32
char = t;code = 116
char = h;code = 104
char = e;code = 101
char = ;code = 32
char = c;code = 99
char = o;code = 111
char = n;code = 110
char = t;code = 116
char = r;code = 114
char = o;code = 111
char = l;code = 108
char = ;code = 32
char = s;code = 115
char = o;code = 111
char = i;code = 105
char = l;code = 108
char = .;code = 46
char = ;code = 32
char = T;code = 84
char = h;code = 104
char = e;code = 101
char = ;code = 32
char = l;code = 108
char = e;code = 101
char = v;code = 118
char = e;code = 101
char = l;code = 108
char = ;code = 32
char = o;code = 111
char = f;code = 102
char = ;code = 32
char = t;code = 116
char = h;code = 104
char = e;code = 101
char = ;code = 32
char = i;code = 105
char = n;code = 110
char = c;code = 99
char = r;code = 114
char = e;code = 101
char = a;code = 97
char = s;code = 115
char = e;code = 101
char = ;code = 32
char = a;code = 97
char = l;code = 108
char = s;code = 115
char = o;code = 111
char = ;code = 32
char = d;code = 100
char = e;code = 101
char = p;code = 112
char = e;code = 101
char = n;code = 110
char = d;code = 100
char = e;code = 101
char = d;code = 100
char = ;code = 32
char = o;code = 111
char = n;code = 110
char = ;code = 32
char = t;code = 116
char = h;code = 104
char = e;code = 101
char = ;code = 32
char = H;code = 72
char = A;code = 65
char = .;code = 46
char = ;code = 32
char = T;code = 84
char = h;code = 104
char = e;code = 101
char = ;code = 32
char = s;code = 115
char = m;code = 109
char = a;code = 97
char = l;code = 108
char = l;code = 108
char = e;code = 101
char = s;code = 115
char = t;code = 116
char = ;code = 32
char = i;code = 105
char = n;code = 110
char = c;code = 99
char = r;code = 114
char = e;code = 101
char = a;code = 97
char = s;code = 115
char = e;code = 101
char = ;code = 32
char = (;code = 40
char = a;code = 97
char = b;code = 98
char = o;code = 111
char = u;code = 117
char = t;code = 116
char = ;code = 32
char = 1;code = 49
char = 0;code = 48
char = ;code = 32
char = t;code = 116
char = i;code = 105
char = m;code = 109
char = e;code = 101
char = s;code = 115
char = );code = 41
char = ;code = 32
char = w;code = 119
char = a;code = 97
char = s;code = 115
char = ;code = 32
char = f;code = 102
char = o;code = 111
char = u;code = 117
char = n;code = 110
char = d;code = 100
char = ;code = 32
char = f;code = 102
char = o;code = 111
char = r;code = 114
char = ;code = 32
char = l;code = 108
char = i;code = 105
char = g;code = 103
char = n;code = 110
char = i;code = 105
char = t;code = 116
char = e;code = 101
char = ;code = 32
char = H;code = 72
char = A;code = 65
char = ;code = 32
char = i;code = 105
char = n;code = 110
char = ;code = 32
char = b;code = 98
char = o;code = 111
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result sql = Contamination of soils with mercury can be a serious problem. It can be mobilized or stabilized by humic substances (HS) containing binding sites with reduced sulfur that can have different binding capacities for CH(3)Hg(+) and for Hg(2+). In this work we investigated the influence of different humic acids (HAs, extracted from lignite, compost, and forest soil) on mercury mobility and availability, both in a model solution and in soil samples from a mercury-polluted region. The technique of diffusive gradients in thin-films (DGT), which is capable of measuring: (i) free metal in solution; (ii) dissociated metal complexes previously mobilized by HA; (iii) mobilized metal-HA complexes that liberate metals by dissociation or by exchange reaction between the metal-HA complexes and the chelating groups on the resin-gel, was used in solutions and soils. The DGT measurements in solution, together with ultrafiltration, allowed estimation of the lability of Hg-HA complexes. Ultrafiltration results were also compared with predictions made by the windermere humic-aqueous model (WHAM). According to both these different approaches, Hg(2+) resulted nearly 100% complexed by HAs, whereas results from ultrafiltration showed that 32 to 72% of the CH(3)Hg(+) was bound to the HAs, with higher values for compost and lower values for forest and Aldrich HA. The DGT-measured mercury in soils was below 0.20 microg L(-1), irrespective of the extent of the contamination. Addition of HA increased the concentration of DGT-measured mercury in soil solution up to 100-fold in the contaminated soil and up to 30-fold in the control soil. The level of the increase also depended on the HA. The smallest increase (about 10 times) was found for lignite HA in both control and contaminated soils. The addition of forest HA gave the largest increases in DGT-measured mercury, in particular for the contaminated soil. Overall, the results demonstrated that DGT can be used for estimating the lability of mercury complexes in solution and for verifying enhanced mercury mobility when HA is added to contaminated soils.

Publication: J. Environ. Qual. 2009 Mar-Apr ;38(2)::493-501. :doi: 10.2134/jeq2008.0175.
Publication Date: 2009 Mar-Apr
Study Author(s): Cattani, I;Zhang, H;Beone, G M;Del Re, A A M;Boccelli, R;Trevisan, M;
Institution: Inst. of Agricultural and Enviromental Chemistry, Università Cattolica del Sacro Cuore, Via Emilia Parmense 29100, Piacenza- Italy. [email protected]
Shortcut link to this study:
Contamination of soils with mercury can be a serious problem. It can be mobilized or stabilized by humic substances (HS) containing binding sites with reduced sulfur that can have different binding capacities for CH(3)Hg(+) and for Hg(2+). In this work we investigated the influence of different humic acids (HAs, extracted from lignite, compost, and forest soil) on mercury mobility and availability, both in a model solution and in soil samples from a mercury-polluted region. The technique of diffusive gradients in thin-films (DGT), which is capable of measuring: (i) free metal in solution; (ii) dissociated metal complexes previously mobilized by HA; (iii) mobilized metal-HA complexes that liberate metals by dissociation or by exchange reaction between the metal-HA complexes and the chelating groups on the resin-gel, was used in solutions and soils. The DGT measurements in solution, together with ultrafiltration, allowed estimation of the lability of Hg-HA complexes. Ultrafiltration results were also compared with predictions made by the windermere humic-aqueous model (WHAM). According to both these different approaches, Hg(2+) resulted nearly 100% complexed by HAs, whereas results from ultrafiltration showed that 32 to 72% of the CH(3)Hg(+) was bound to the HAs, with higher values for compost and lower values for forest and Aldrich HA. The DGT-measured mercury in soils was below 0.20 microg L(-1), irrespective of the extent of the contamination. Addition of HA increased the concentration of DGT-measured mercury in soil solution up to 100-fold in the contaminated soil and up to 30-fold in the control soil. The level of the increase also depended on the HA. The smallest increase (about 10 times) was found for lignite HA in both control and contaminated soils. The addition of forest HA gave the largest increases in DGT-measured mercury, in particular for the contaminated soil. Overall, the results demonstrated that DGT can be used for estimating the lability of mercury complexes in solution and for verifying enhanced mercury mobility when HA is added to contaminated soils.
PMID: 19202019

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