char = C;code = 67
char = o;code = 111
char = m;code = 109
char = p;code = 112
char = a;code = 97
char = r;code = 114
char = i;code = 105
char = s;code = 115
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 = r;code = 114
char = e;code = 101
char = e;code = 101
char = ;code = 32
char = s;code = 115
char = e;code = 101
char = q;code = 113
char = u;code = 117
char = e;code = 101
char = n;code = 110
char = t;code = 116
char = i;code = 105
char = a;code = 97
char = l;code = 108
char = ;code = 32
char = e;code = 101
char = x;code = 120
char = t;code = 116
char = r;code = 114
char = a;code = 97
char = c;code = 99
char = t;code = 116
char = i;code = 105
char = o;code = 111
char = n;code = 110
char = ;code = 32
char = p;code = 112
char = r;code = 114
char = o;code = 111
char = c;code = 99
char = e;code = 101
char = d;code = 100
char = u;code = 117
char = r;code = 114
char = e;code = 101
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 = t;code = 116
char = o;code = 111
char = ;code = 32
char = s;code = 115
char = t;code = 116
char = u;code = 117
char = d;code = 100
char = y;code = 121
char = ;code = 32
char = t;code = 116
char = r;code = 114
char = a;code = 97
char = c;code = 99
char = e;code = 101
char = ;code = 32
char = m;code = 109
char = e;code = 101
char = t;code = 116
char = a;code = 97
char = l;code = 108
char = ;code = 32
char = d;code = 100
char = i;code = 105
char = s;code = 115
char = t;code = 116
char = r;code = 114
char = i;code = 105
char = b;code = 98
char = u;code = 117
char = t;code = 116
char = i;code = 105
char = o;code = 111
char = n;code = 110
char = ;code = 32
char = i;code = 105
char = n;code = 110
char = ;code = 32
char = a;code = 97
char = n;code = 110
char = ;code = 32
char = a;code = 97
char = c;code = 99
char = i;code = 105
char = d;code = 100
char = i;code = 105
char = c;code = 99
char = ;code = 32
char = s;code = 115
char = a;code = 97
char = n;code = 110
char = d;code = 100
char = y;code = 121
char = ;code = 32
char = s;code = 115
char = o;code = 111
char = i;code = 105
char = l;code = 108
char = .;code = 46
result sql = Comparison of three sequential extraction procedures used to study trace metal distribution in an acidic sandy soil.
Comparison of three sequential extraction procedures used to study trace metal distribution in an acidic sandy soil.
char = O;code = 79
char = n;code = 110
char = ;code = 32
char = a;code = 97
char = n;code = 110
char = ;code = 32
char = a;code = 97
char = c;code = 99
char = i;code = 105
char = d;code = 100
char = ;code = 32
char = s;code = 115
char = a;code = 97
char = n;code = 110
char = d;code = 100
char = y;code = 121
char = ;code = 32
char = s;code = 115
char = o;code = 111
char = i;code = 105
char = l;code = 108
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 = w;code = 119
char = i;code = 105
char = t;code = 116
char = h;code = 104
char = ;code = 32
char = t;code = 116
char = r;code = 114
char = a;code = 97
char = c;code = 99
char = e;code = 101
char = ;code = 32
char = m;code = 109
char = e;code = 101
char = t;code = 116
char = a;code = 97
char = l;code = 108
char = s;code = 115
char = ;code = 32
char = (;code = 40
char = F;code = 70
char = e;code = 101
char = ,;code = 44
char = ;code = 32
char = M;code = 77
char = n;code = 110
char = ,;code = 44
char = ;code = 32
char = C;code = 67
char = u;code = 117
char = ,;code = 44
char = ;code = 32
char = P;code = 80
char = b;code = 98
char = ;code = 32
char = a;code = 97
char = n;code = 110
char = d;code = 100
char = ;code = 32
char = Z;code = 90
char = n;code = 110
char = );code = 41
char = ,;code = 44
char = ;code = 32
char = t;code = 116
char = h;code = 104
char = r;code = 114
char = e;code = 101
char = e;code = 101
char = ;code = 32
char = s;code = 115
char = e;code = 101
char = q;code = 113
char = u;code = 117
char = e;code = 101
char = n;code = 110
char = t;code = 116
char = i;code = 105
char = a;code = 97
char = l;code = 108
char = ;code = 32
char = e;code = 101
char = x;code = 120
char = t;code = 116
char = r;code = 114
char = a;code = 97
char = c;code = 99
char = t;code = 116
char = i;code = 105
char = o;code = 111
char = n;code = 110
char = ;code = 32
char = p;code = 112
char = r;code = 114
char = o;code = 111
char = c;code = 99
char = e;code = 101
char = d;code = 100
char = u;code = 117
char = r;code = 114
char = e;code = 101
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 = 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 = t;code = 116
char = o;code = 111
char = ;code = 32
char = d;code = 100
char = e;code = 101
char = t;code = 116
char = e;code = 101
char = r;code = 114
char = m;code = 109
char = i;code = 105
char = n;code = 110
char = e;code = 101
char = ;code = 32
char = t;code = 116
char = h;code = 104
char = e;code = 101
char = ;code = 32
char = e;code = 101
char = f;code = 102
char = f;code = 102
char = i;code = 105
char = c;code = 99
char = i;code = 105
char = e;code = 101
char = n;code = 110
char = c;code = 99
char = y;code = 121
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 = r;code = 114
char = e;code = 101
char = a;code = 97
char = g;code = 103
char = e;code = 101
char = n;code = 110
char = t;code = 116
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 = a;code = 97
char = n;code = 110
char = d;code = 100
char = ;code = 32
char = t;code = 116
char = h;code = 104
char = e;code = 101
char = ;code = 32
char = e;code = 101
char = f;code = 102
char = f;code = 102
char = e;code = 101
char = c;code = 99
char = t;code = 116
char = s;code = 115
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 = s;code = 115
char = t;code = 116
char = e;code = 101
char = p;code = 112
char = ;code = 32
char = o;code = 111
char = r;code = 114
char = d;code = 100
char = e;code = 101
char = r;code = 114
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 = f;code = 102
char = r;code = 114
char = a;code = 97
char = c;code = 99
char = t;code = 116
char = i;code = 105
char = o;code = 111
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 = 32
char = o;code = 111
char = f;code = 102
char = ;code = 32
char = m;code = 109
char = e;code = 101
char = t;code = 116
char = a;code = 97
char = l;code = 108
char = ;code = 32
char = s;code = 115
char = p;code = 112
char = e;code = 101
char = c;code = 99
char = i;code = 105
char = e;code = 101
char = s;code = 115
char = .;code = 46
char = ;code = 32
char = I;code = 73
char = n;code = 110
char = ;code = 32
char = a;code = 97
char = l;code = 108
char = l;code = 108
char = ;code = 32
char = c;code = 99
char = a;code = 97
char = s;code = 115
char = e;code = 101
char = s;code = 115
char = ,;code = 44
char = ;code = 32
char = a;code = 97
char = ;code = 32
char = m;code = 109
char = a;code = 97
char = g;code = 103
char = n;code = 110
char = e;code = 101
char = s;code = 115
char = i;code = 105
char = u;code = 117
char = m;code = 109
char = ;code = 32
char = n;code = 110
char = i;code = 105
char = t;code = 116
char = r;code = 114
char = a;code = 97
char = t;code = 116
char = e;code = 101
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 = (;code = 40
char = M;code = 77
char = g;code = 103
char = N;code = 78
char = I;code = 73
char = T;code = 84
char = );code = 41
char = ;code = 32
char = w;code = 119
char = a;code = 97
char = s;code = 115
char = ;code = 32
char = p;code = 112
char = r;code = 114
char = e;code = 101
char = v;code = 118
char = i;code = 105
char = o;code = 111
char = u;code = 117
char = s;code = 115
char = l;code = 108
char = y;code = 121
char = ;code = 32
char = u;code = 117
char = s;code = 115
char = e;code = 101
char = d;code = 100
char = ;code = 32
char = t;code = 116
char = o;code = 111
char = ;code = 32
char = e;code = 101
char = x;code = 120
char = t;code = 116
char = r;code = 114
char = a;code = 97
char = c;code = 99
char = t;code = 116
char = ;code = 32
char = e;code = 101
char = x;code = 120
char = c;code = 99
char = h;code = 104
char = a;code = 97
char = n;code = 110
char = g;code = 103
char = e;code = 101
char = a;code = 97
char = b;code = 98
char = l;code = 108
char = e;code = 101
char = ;code = 32
char = f;code = 102
char = o;code = 111
char = r;code = 114
char = m;code = 109
char = s;code = 115
char = .;code = 46
char = ;code = 32
char = I;code = 73
char = n;code = 110
char = ;code = 32
char = t;code = 116
char = h;code = 104
char = e;code = 101
char = ;code = 32
char = f;code = 102
char = i;code = 105
char = r;code = 114
char = s;code = 115
char = t;code = 116
char = ;code = 32
char = p;code = 112
char = r;code = 114
char = o;code = 111
char = c;code = 99
char = e;code = 101
char = d;code = 100
char = u;code = 117
char = r;code = 114
char = e;code = 101
char = ;code = 32
char = (;code = 40
char = I;code = 73
char = );code = 41
char = ,;code = 44
char = ;code = 32
char = t;code = 116
char = h;code = 104
char = e;code = 101
char = ;code = 32
char = n;code = 110
char = e;code = 101
char = x;code = 120
char = t;code = 116
char = ;code = 32
char = e;code = 101
char = x;code = 120
char = t;code = 116
char = r;code = 114
char = a;code = 97
char = c;code = 99
char = t;code = 116
char = i;code = 105
char = o;code = 111
char = n;code = 110
char = ;code = 32
char = s;code = 115
char = t;code = 116
char = e;code = 101
char = p;code = 112
char = ;code = 32
char = w;code = 119
char = a;code = 97
char = s;code = 115
char = ;code = 32
char = p;code = 112
char = e;code = 101
char = r;code = 114
char = f;code = 102
char = o;code = 111
char = r;code = 114
char = m;code = 109
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 = s;code = 115
char = o;code = 111
char = d;code = 100
char = i;code = 105
char = u;code = 117
char = m;code = 109
char = ;code = 32
char = a;code = 97
char = c;code = 99
char = e;code = 101
char = t;code = 116
char = a;code = 97
char = t;code = 116
char = e;code = 101
char = ;code = 32
char = b;code = 98
char = u;code = 117
char = f;code = 102
char = f;code = 102
char = e;code = 101
char = r;code = 114
char = ;code = 32
char = (;code = 40
char = N;code = 78
char = a;code = 97
char = O;code = 79
char = A;code = 65
char = c;code = 99
char = );code = 41
char = ,;code = 44
char = ;code = 32
char = a;code = 97
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 = o;code = 111
char = n;code = 110
char = ;code = 32
char = c;code = 99
char = a;code = 97
char = l;code = 108
char = c;code = 99
char = a;code = 97
char = r;code = 114
char = e;code = 101
char = o;code = 111
char = u;code = 117
char = s;code = 115
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 = 44
char = ;code = 32
char = t;code = 116
char = o;code = 111
char = ;code = 32
char = d;code = 100
char = i;code = 105
char = s;code = 115
char = s;code = 115
char = o;code = 111
char = l;code = 108
char = v;code = 118
char = e;code = 101
char = ;code = 32
char = a;code = 97
char = c;code = 99
char = t;code = 116
char = i;code = 105
char = v;code = 118
char = e;code = 101
char = ;code = 32
char = c;code = 99
char = a;code = 97
char = l;code = 108
char = c;code = 99
char = i;code = 105
char = u;code = 117
char = m;code = 109
char = ;code = 32
char = c;code = 99
char = a;code = 97
char = r;code = 114
char = b;code = 98
char = o;code = 111
char = n;code = 110
char = a;code = 97
char = t;code = 116
char = e;code = 101
char = .;code = 46
char = ;code = 32
char = T;code = 84
char = h;code = 104
char = e;code = 101
char = n;code = 110
char = ;code = 32
char = t;code = 116
char = r;code = 114
char = a;code = 97
char = c;code = 99
char = e;code = 101
char = ;code = 32
char = m;code = 109
char = e;code = 101
char = t;code = 116
char = a;code = 97
char = l;code = 108
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 = 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 = f;code = 102
char = o;code = 111
char = r;code = 114
char = m;code = 109
char = s;code = 115
char = ;code = 32
char = o;code = 111
char = f;code = 102
char = ;code = 32
char = o;code = 111
char = x;code = 120
char = i;code = 105
char = -;code = 45
char = h;code = 104
char = y;code = 121
char = d;code = 100
char = r;code = 114
char = o;code = 111
char = x;code = 120
char = i;code = 105
char = d;code = 100
char = e;code = 101
char = s;code = 115
char = ;code = 32
char = (;code = 40
char = N;code = 78
char = H;code = 72
char = (;code = 40
char = 2;code = 50
char = );code = 41
char = O;code = 79
char = H;code = 72
char = ,;code = 44
char = ;code = 32
char = T;code = 84
char = A;code = 65
char = M;code = 77
char = O;code = 79
char = x;code = 120
char = ;code = 32
char = a;code = 97
char = n;code = 110
char = d;code = 100
char = ;code = 32
char = T;code = 84
char = A;code = 65
char = M;code = 77
char = A;code = 65
char = s;code = 115
char = ;code = 32
char = f;code = 102
char = r;code = 114
char = a;code = 97
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 = 41
char = ;code = 32
char = w;code = 119
char = e;code = 101
char = r;code = 114
char = e;code = 101
char = ;code = 32
char = e;code = 101
char = x;code = 120
char = t;code = 116
char = r;code = 114
char = a;code = 97
char = c;code = 99
char = t;code = 116
char = e;code = 101
char = d;code = 100
char = ;code = 32
char = b;code = 98
char = e;code = 101
char = f;code = 102
char = o;code = 111
char = r;code = 114
char = e;code = 101
char = ;code = 32
char = o;code = 111
char = r;code = 114
char = g;code = 103
char = a;code = 97
char = n;code = 110
char = i;code = 105
char = c;code = 99
char = ;code = 32
char = m;code = 109
char = a;code = 97
char = t;code = 116
char = t;code = 116
char = e;code = 101
char = r;code = 114
char = /;code = 47
char = s;code = 115
char = u;code = 117
char = l;code = 108
char = f;code = 102
char = i;code = 105
char = d;code = 100
char = e;code = 101
char = ;code = 32
char = o;code = 111
char = x;code = 120
char = i;code = 105
char = d;code = 100
char = a;code = 97
char = t;code = 116
char = i;code = 105
char = o;code = 111
char = n;code = 110
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 = y;code = 121
char = d;code = 100
char = r;code = 114
char = o;code = 111
char = g;code = 103
char = e;code = 101
char = n;code = 110
char = ;code = 32
char = p;code = 112
char = e;code = 101
char = r;code = 114
char = o;code = 111
char = x;code = 120
char = i;code = 105
char = d;code = 100
char = e;code = 101
char = ;code = 32
char = a;code = 97
char = t;code = 116
char = ;code = 32
char = p;code = 112
char = H;code = 72
char = ;code = 32
char = 2;code = 50
char = .;code = 46
char = 0;code = 48
char = ;code = 32
char = i;code = 105
char = n;code = 110
char = ;code = 32
char = n;code = 110
char = i;code = 105
char = t;code = 116
char = r;code = 114
char = i;code = 105
char = c;code = 99
char = ;code = 32
char = a;code = 97
char = c;code = 99
char = i;code = 105
char = d;code = 100
char = ;code = 32
char = m;code = 109
char = e;code = 101
char = d;code = 100
char = i;code = 105
char = u;code = 117
char = m;code = 109
char = ;code = 32
char = (;code = 40
char = O;code = 79
char = M;code = 77
char = H;code = 72
char = y;code = 121
char = d;code = 100
char = );code = 41
char = .;code = 46
char = ;code = 32
char = F;code = 70
char = i;code = 105
char = n;code = 110
char = a;code = 97
char = l;code = 108
char = l;code = 108
char = y;code = 121
char = ,;code = 44
char = ;code = 32
char = r;code = 114
char = e;code = 101
char = s;code = 115
char = i;code = 105
char = d;code = 100
char = u;code = 117
char = a;code = 97
char = l;code = 108
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 = m;code = 109
char = e;code = 101
char = t;code = 116
char = a;code = 97
char = l;code = 108
char = s;code = 115
char = ;code = 32
char = (;code = 40
char = R;code = 82
char = E;code = 69
char = S;code = 83
char = I;code = 73
char = D;code = 68
char = );code = 41
char = ;code = 32
char = i;code = 105
char = n;code = 110
char = ;code = 32
char = e;code = 101
char = a;code = 97
char = c;code = 99
char = h;code = 104
char = ;code = 32
char = p;code = 112
char = r;code = 114
char = o;code = 111
char = c;code = 99
char = e;code = 101
char = d;code = 100
char = u;code = 117
char = r;code = 114
char = e;code = 101
char = ;code = 32
char = w;code = 119
char = e;code = 101
char = r;code = 114
char = e;code = 101
char = ;code = 32
char = e;code = 101
char = x;code = 120
char = t;code = 116
char = r;code = 114
char = a;code = 97
char = c;code = 99
char = t;code = 116
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 = a;code = 97
char = ;code = 32
char = n;code = 110
char = i;code = 105
char = t;code = 116
char = r;code = 114
char = i;code = 105
char = c;code = 99
char = -;code = 45
char = h;code = 104
char = y;code = 121
char = d;code = 100
char = r;code = 114
char = o;code = 111
char = f;code = 102
char = l;code = 108
char = u;code = 117
char = o;code = 111
char = r;code = 114
char = i;code = 105
char = c;code = 99
char = -;code = 45
char = p;code = 112
char = e;code = 101
char = r;code = 114
char = c;code = 99
char = h;code = 104
char = l;code = 108
char = o;code = 111
char = r;code = 114
char = i;code = 105
char = c;code = 99
char = ;code = 32
char = a;code = 97
char = c;code = 99
char = i;code = 105
char = d;code = 100
char = ;code = 32
char = m;code = 109
char = i;code = 105
char = x;code = 120
char = t;code = 116
char = u;code = 117
char = r;code = 114
char = e;code = 101
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 = e;code = 101
char = c;code = 99
char = o;code = 111
char = n;code = 110
char = d;code = 100
char = ;code = 32
char = p;code = 112
char = r;code = 114
char = o;code = 111
char = c;code = 99
char = e;code = 101
char = d;code = 100
char = u;code = 117
char = r;code = 114
char = e;code = 101
char = ;code = 32
char = (;code = 40
char = I;code = 73
char = I;code = 73
char = );code = 41
char = ;code = 32
char = w;code = 119
char = a;code = 97
char = s;code = 115
char = ;code = 32
char = t;code = 116
char = h;code = 104
char = e;code = 101
char = ;code = 32
char = s;code = 115
char = a;code = 97
char = m;code = 109
char = e;code = 101
char = ;code = 32
char = a;code = 97
char = s;code = 115
char = ;code = 32
char = I;code = 73
char = ,;code = 44
char = ;code = 32
char = b;code = 98
char = u;code = 117
char = t;code = 116
char = ;code = 32
char = w;code = 119
char = i;code = 105
char = t;code = 116
char = h;code = 104
char = o;code = 111
char = u;code = 117
char = t;code = 116
char = ;code = 32
char = t;code = 116
char = h;code = 104
char = e;code = 101
char = ;code = 32
char = N;code = 78
char = a;code = 97
char = O;code = 79
char = A;code = 65
char = c;code = 99
char = ;code = 32
char = s;code = 115
char = t;code = 116
char = e;code = 101
char = p;code = 112
char = ,;code = 44
char = ;code = 32
char = b;code = 98
char = e;code = 101
char = c;code = 99
char = a;code = 97
char = u;code = 117
char = s;code = 115
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 = a;code = 97
char = b;code = 98
char = s;code = 115
char = e;code = 101
char = n;code = 110
char = c;code = 99
char = e;code = 101
char = ;code = 32
char = o;code = 111
char = f;code = 102
char = ;code = 32
char = c;code = 99
char = a;code = 97
char = r;code = 114
char = b;code = 98
char = o;code = 111
char = n;code = 110
char = a;code = 97
char = t;code = 116
char = e;code = 101
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 = s;code = 115
char = t;code = 116
char = u;code = 117
char = d;code = 100
char = y;code = 121
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 = I;code = 73
char = n;code = 110
char = ;code = 32
char = p;code = 112
char = r;code = 114
char = o;code = 111
char = c;code = 99
char = e;code = 101
char = d;code = 100
char = u;code = 117
char = r;code = 114
char = e;code = 101
char = ;code = 32
char = I;code = 73
char = I;code = 73
char = I;code = 73
char = ,;code = 44
char = ;code = 32
char = t;code = 116
char = h;code = 104
char = e;code = 101
char = ;code = 32
char = N;code = 78
char = a;code = 97
char = O;code = 79
char = A;code = 65
char = c;code = 99
char = ;code = 32
char = s;code = 115
char = t;code = 116
char = e;code = 101
char = p;code = 112
char = ;code = 32
char = w;code = 119
char = a;code = 97
char = s;code = 115
char = ;code = 32
char = o;code = 111
char = m;code = 109
char = i;code = 105
char = t;code = 116
char = t;code = 116
char = e;code = 101
char = d;code = 100
char = ;code = 32
char = a;code = 97
char = n;code = 110
char = d;code = 100
char = ;code = 32
char = t;code = 116
char = h;code = 104
char = e;code = 101
char = ;code = 32
char = o;code = 111
char = x;code = 120
char = i;code = 105
char = d;code = 100
char = i;code = 105
char = z;code = 122
char = a;code = 97
char = b;code = 98
char = l;code = 108
char = e;code = 101
char = ;code = 32
char = o;code = 111
char = r;code = 114
char = g;code = 103
char = a;code = 97
char = n;code = 110
char = i;code = 105
char = c;code = 99
char = /;code = 47
char = s;code = 115
char = u;code = 117
char = l;code = 108
char = f;code = 102
char = i;code = 105
char = d;code = 100
char = e;code = 101
char = ;code = 32
char = f;code = 102
char = r;code = 114
char = a;code = 97
char = c;code = 99
char = t;code = 116
char = i;code = 105
char = o;code = 111
char = n;code = 110
char = ;code = 32
char = w;code = 119
char = a;code = 97
char = s;code = 115
char = ;code = 32
char = e;code = 101
char = x;code = 120
char = t;code = 116
char = r;code = 114
char = a;code = 97
char = c;code = 99
char = t;code = 116
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 = s;code = 115
char = o;code = 111
char = d;code = 100
char = i;code = 105
char = u;code = 117
char = m;code = 109
char = ;code = 32
char = h;code = 104
char = y;code = 121
char = p;code = 112
char = o;code = 111
char = c;code = 99
char = h;code = 104
char = l;code = 108
char = o;code = 111
char = r;code = 114
char = i;code = 105
char = t;code = 116
char = e;code = 101
char = ;code = 32
char = a;code = 97
char = t;code = 116
char = ;code = 32
char = p;code = 112
char = H;code = 72
char = ;code = 32
char = 8;code = 56
char = .;code = 46
char = 5;code = 53
char = ;code = 32
char = (;code = 40
char = O;code = 79
char = M;code = 77
char = O;code = 79
char = C;code = 67
char = l;code = 108
char = );code = 41
char = ;code = 32
char = b;code = 98
char = e;code = 101
char = f;code = 102
char = o;code = 111
char = r;code = 114
char = e;code = 101
char = ;code = 32
char = t;code = 116
char = h;code = 104
char = e;code = 101
char = ;code = 32
char = r;code = 114
char = e;code = 101
char = d;code = 100
char = u;code = 117
char = c;code = 99
char = i;code = 105
char = b;code = 98
char = l;code = 108
char = e;code = 101
char = ;code = 32
char = f;code = 102
char = r;code = 114
char = a;code = 97
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 = 46
char = ;code = 32
char = T;code = 84
char = h;code = 104
char = i;code = 105
char = s;code = 115
char = ;code = 32
char = s;code = 115
char = t;code = 116
char = u;code = 117
char = d;code = 100
char = y;code = 121
char = ;code = 32
char = f;code = 102
char = i;code = 105
char = r;code = 114
char = s;code = 115
char = t;code = 116
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 = N;code = 78
char = a;code = 97
char = O;code = 79
char = A;code = 65
char = c;code = 99
char = ;code = 32
char = m;code = 109
char = a;code = 97
char = y;code = 121
char = ;code = 32
char = r;code = 114
char = e;code = 101
char = m;code = 109
char = o;code = 111
char = v;code = 118
char = e;code = 101
char = ;code = 32
char = c;code = 99
char = o;code = 111
char = n;code = 110
char = s;code = 115
char = i;code = 105
char = d;code = 100
char = e;code = 101
char = r;code = 114
char = a;code = 97
char = b;code = 98
char = l;code = 108
char = e;code = 101
char = ;code = 32
char = a;code = 97
char = m;code = 109
char = o;code = 111
char = u;code = 117
char = n;code = 110
char = t;code = 116
char = s;code = 115
char = ;code = 32
char = o;code = 111
char = f;code = 102
char = ;code = 32
char = m;code = 109
char = e;code = 101
char = t;code = 116
char = a;code = 97
char = l;code = 108
char = s;code = 115
char = ;code = 32
char = (;code = 40
char = e;code = 101
char = s;code = 115
char = p;code = 112
char = e;code = 101
char = c;code = 99
char = i;code = 105
char = a;code = 97
char = l;code = 108
char = l;code = 108
char = y;code = 121
char = ;code = 32
char = M;code = 77
char = n;code = 110
char = ;code = 32
char = a;code = 97
char = n;code = 110
char = d;code = 100
char = ;code = 32
char = Z;code = 90
char = n;code = 110
char = );code = 41
char = ;code = 32
char = i;code = 105
char = n;code = 110
char = ;code = 32
char = o;code = 111
char = t;code = 116
char = h;code = 104
char = e;code = 101
char = r;code = 114
char = ;code = 32
char = f;code = 102
char = o;code = 111
char = r;code = 114
char = m;code = 109
char = s;code = 115
char = ;code = 32
char = t;code = 116
char = h;code = 104
char = a;code = 97
char = n;code = 110
char = ;code = 32
char = e;code = 101
char = x;code = 120
char = c;code = 99
char = h;code = 104
char = a;code = 97
char = n;code = 110
char = g;code = 103
char = e;code = 101
char = a;code = 97
char = b;code = 98
char = l;code = 108
char = e;code = 101
char = ;code = 32
char = o;code = 111
char = n;code = 110
char = e;code = 101
char = s;code = 115
char = .;code = 46
char = ;code = 32
char = P;code = 80
char = r;code = 114
char = o;code = 111
char = c;code = 99
char = e;code = 101
char = d;code = 100
char = u;code = 117
char = r;code = 114
char = e;code = 101
char = s;code = 115
char = ;code = 32
char = I;code = 73
char = I;code = 73
char = ;code = 32
char = a;code = 97
char = n;code = 110
char = d;code = 100
char = ;code = 32
char = I;code = 73
char = I;code = 73
char = I;code = 73
char = ;code = 32
char = g;code = 103
char = i;code = 105
char = v;code = 118
char = e;code = 101
char = ;code = 32
char = s;code = 115
char = i;code = 105
char = m;code = 109
char = i;code = 105
char = l;code = 108
char = a;code = 97
char = r;code = 114
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 = o;code = 111
char = r;code = 114
char = ;code = 32
char = F;code = 70
char = e;code = 101
char = ,;code = 44
char = ;code = 32
char = M;code = 77
char = n;code = 110
char = ;code = 32
char = a;code = 97
char = n;code = 110
char = d;code = 100
char = ;code = 32
char = Z;code = 90
char = n;code = 110
char = ;code = 32
char = f;code = 102
char = o;code = 111
char = r;code = 114
char = m;code = 109
char = s;code = 115
char = ,;code = 44
char = ;code = 32
char = w;code = 119
char = h;code = 104
char = i;code = 105
char = c;code = 99
char = h;code = 104
char = ;code = 32
char = w;code = 119
char = e;code = 101
char = r;code = 114
char = e;code = 101
char = ;code = 32
char = m;code = 109
char = a;code = 97
char = i;code = 105
char = n;code = 110
char = l;code = 108
char = y;code = 121
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 = i;code = 105
char = n;code = 110
char = ;code = 32
char = f;code = 102
char = r;code = 114
char = a;code = 97
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 = o;code = 111
char = f;code = 102
char = ;code = 32
char = i;code = 105
char = n;code = 110
char = o;code = 111
char = r;code = 114
char = g;code = 103
char = a;code = 97
char = n;code = 110
char = i;code = 105
char = c;code = 99
char = ;code = 32
char = s;code = 115
char = o;code = 111
char = i;code = 105
char = l;code = 108
char = ;code = 32
char = c;code = 99
char = o;code = 111
char = m;code = 109
char = p;code = 112
char = o;code = 111
char = n;code = 110
char = e;code = 101
char = n;code = 110
char = t;code = 116
char = s;code = 115
char = ,;code = 44
char = ;code = 32
char = b;code = 98
char = u;code = 117
char = t;code = 116
char = ;code = 32
char = n;code = 110
char = o;code = 111
char = t;code = 116
char = ;code = 32
char = f;code = 102
char = o;code = 111
char = r;code = 114
char = ;code = 32
char = C;code = 67
char = u;code = 117
char = ;code = 32
char = a;code = 97
char = n;code = 110
char = d;code = 100
char = ;code = 32
char = P;code = 80
char = b;code = 98
char = .;code = 46
char = ;code = 32
char = C;code = 67
char = o;code = 111
char = p;code = 112
char = p;code = 112
char = e;code = 101
char = r;code = 114
char = ;code = 32
char = d;code = 100
char = i;code = 105
char = s;code = 115
char = t;code = 116
char = r;code = 114
char = i;code = 105
char = b;code = 98
char = u;code = 117
char = t;code = 116
char = i;code = 105
char = o;code = 111
char = n;code = 110
char = ;code = 32
char = w;code = 119
char = a;code = 97
char = s;code = 115
char = ;code = 32
char = a;code = 97
char = f;code = 102
char = f;code = 102
char = e;code = 101
char = c;code = 99
char = t;code = 116
char = e;code = 101
char = d;code = 100
char = ;code = 32
char = b;code = 98
char = y;code = 121
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char = t;code = 116
char = h;code = 104
char = e;code = 101
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char = p;code = 112
char = o;code = 111
char = s;code = 115
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 = t;code = 116
char = h;code = 104
char = e;code = 101
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char = o;code = 111
char = x;code = 120
char = i;code = 105
char = d;code = 100
char = a;code = 97
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char = o;code = 111
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char = ;code = 32
char = s;code = 115
char = t;code = 116
char = e;code = 101
char = p;code = 112
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char = i;code = 105
char = n;code = 110
char = ;code = 32
char = t;code = 116
char = h;code = 104
char = e;code = 101
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char = s;code = 115
char = e;code = 101
char = q;code = 113
char = u;code = 117
char = e;code = 101
char = n;code = 110
char = c;code = 99
char = e;code = 101
char = .;code = 46
char = ;code = 32
char = I;code = 73
char = n;code = 110
char = ;code = 32
char = p;code = 112
char = r;code = 114
char = o;code = 111
char = c;code = 99
char = e;code = 101
char = d;code = 100
char = u;code = 117
char = r;code = 114
char = e;code = 101
char = ;code = 32
char = I;code = 73
char = I;code = 73
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 = ;code = 32
char = t;code = 116
char = h;code = 104
char = e;code = 101
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char = o;code = 111
char = x;code = 120
char = i;code = 105
char = d;code = 100
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 = t;code = 116
char = e;code = 101
char = p;code = 112
char = ;code = 32
char = (;code = 40
char = O;code = 79
char = M;code = 77
char = H;code = 72
char = y;code = 121
char = d;code = 100
char = );code = 41
char = ;code = 32
char = e;code = 101
char = n;code = 110
char = d;code = 100
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 = s;code = 115
char = e;code = 101
char = q;code = 113
char = u;code = 117
char = e;code = 101
char = n;code = 110
char = c;code = 99
char = e;code = 101
char = ,;code = 44
char = ;code = 32
char = C;code = 67
char = u;code = 117
char = ;code = 32
char = w;code = 119
char = a;code = 97
char = s;code = 115
char = ;code = 32
char = m;code = 109
char = a;code = 97
char = i;code = 105
char = n;code = 110
char = l;code = 108
char = y;code = 121
char = ;code = 32
char = r;code = 114
char = e;code = 101
char = c;code = 99
char = o;code = 111
char = v;code = 118
char = e;code = 101
char = r;code = 114
char = e;code = 101
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 = T;code = 84
char = A;code = 65
char = M;code = 77
char = O;code = 79
char = x;code = 120
char = ;code = 32
char = f;code = 102
char = r;code = 114
char = a;code = 97
char = c;code = 99
char = t;code = 116
char = i;code = 105
char = o;code = 111
char = n;code = 110
char = .;code = 46
char = ;code = 32
char = H;code = 72
char = o;code = 111
char = w;code = 119
char = e;code = 101
char = v;code = 118
char = e;code = 101
char = r;code = 114
char = ,;code = 44
char = ;code = 32
char = i;code = 105
char = n;code = 110
char = ;code = 32
char = p;code = 112
char = r;code = 114
char = o;code = 111
char = c;code = 99
char = e;code = 101
char = d;code = 100
char = u;code = 117
char = r;code = 114
char = e;code = 101
char = ;code = 32
char = I;code = 73
char = I;code = 73
char = I;code = 73
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 = ;code = 32
char = t;code = 116
char = h;code = 104
char = e;code = 101
char = ;code = 32
char = o;code = 111
char = x;code = 120
char = i;code = 105
char = d;code = 100
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 = t;code = 116
char = e;code = 101
char = p;code = 112
char = ;code = 32
char = (;code = 40
char = O;code = 79
char = M;code = 77
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char = ;code = 32
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char = I;code = 73
char = D;code = 68
char = A;code = 65
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char = I;code = 73
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char = E;code = 69
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char = ;code = 32
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char = c;code = 99
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char = i;code = 105
char = o;code = 111
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char = o;code = 111
char = f;code = 102
char = ;code = 32
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char = c;code = 99
char = e;code = 101
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char = r;code = 114
char = e;code = 101
char = s;code = 115
char = ;code = 32
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char = ;code = 32
char = a;code = 97
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char = ;code = 32
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char = d;code = 100
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char = n;code = 110
char = ;code = 32
char = t;code = 116
char = h;code = 104
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char = ;code = 32
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char = M;code = 77
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char = c;code = 99
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char = n;code = 110
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char = I;code = 73
char = I;code = 73
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char = ;code = 32
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char = r;code = 114
char = o;code = 111
char = b;code = 98
char = a;code = 97
char = b;code = 98
char = l;code = 108
char = y;code = 121
char = ;code = 32
char = d;code = 100
char = u;code = 117
char = e;code = 101
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
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char = k;code = 107
char = a;code = 97
char = l;code = 108
char = i;code = 105
char = n;code = 110
char = e;code = 101
char = ;code = 32
char = p;code = 112
char = H;code = 72
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
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char = e;code = 101
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char = g;code = 103
char = e;code = 101
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char = t;code = 116
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 = l;code = 108
char = a;code = 97
char = t;code = 116
char = t;code = 116
char = e;code = 101
char = r;code = 114
char = ;code = 32
char = c;code = 99
char = a;code = 97
char = s;code = 115
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result sql = On an acid sandy soil contaminated with trace metals (Fe, Mn, Cu, Pb and Zn), three sequential extraction procedures were compared to determine the efficiency of the reagents used and the effects of the step order on the fractionation of metal species. In all cases, a magnesium nitrate solution (MgNIT) was previously used to extract exchangeable forms. In the first procedure (I), the next extraction step was performed with sodium acetate buffer (NaOAc), as used on calcareous soils, to dissolve active calcium carbonate. Then trace metals bound to different forms of oxi-hydroxides (NH(2)OH, TAMOx and TAMAs fractions) were extracted before organic matter/sulfide oxidation with hydrogen peroxide at pH 2.0 in nitric acid medium (OMHyd). Finally, residual bound metals (RESID) in each procedure were extracted with a nitric-hydrofluoric-perchloric acid mixture. The second procedure (II) was the same as I, but without the NaOAc step, because of the absence of carbonate in the study soil. In procedure III, the NaOAc step was omitted and the oxidizable organic/sulfide fraction was extracted with sodium hypochlorite at pH 8.5 (OMOCl) before the reducible fractions. This study first showed that NaOAc may remove considerable amounts of metals (especially Mn and Zn) in other forms than exchangeable ones. Procedures II and III give similar results for Fe, Mn and Zn forms, which were mainly found in fractions of inorganic soil components, but not for Cu and Pb. Copper distribution was affected by the position of the oxidation step in the sequence. In procedure II, where the oxidation step (OMHyd) ended the sequence, Cu was mainly recovered in the TAMOx fraction. However, in procedure III, where the oxidation step (OMOCl) preceded the NH(2)OH, TAMOx and TAMAs steps, Cu was found in both OMOCl and TAMOx fractions. LEAD DISTRIBUTION VARIED WITH OXIDATION REAGENT: it was partly removed in the OMHyd fraction of procedures I and II, and to a much lower extent in the OMOCl fraction of procedure III, probably due to the alkaline pH of the reagent in the latter case.

Publication: Anal Bioanal Chem 2003 May ;376(2)::243-7.
Publication Date: 2003 May
Study Author(s): Parat, Corinne;Lévêque, Jean;Dousset, Sylvie;Chaussod, Rémi;Andreux, Francis;
Institution: Microbiologie et Géochimie des Sols, Centre des Sciences de la Terre 6, UMR INRA 111, Boulevard Gabriel, 21000 Dijon, France. Corinne.Parat@u-bourgogne.fr
Shortcut link to this study:
On an acid sandy soil contaminated with trace metals (Fe, Mn, Cu, Pb and Zn), three sequential extraction procedures were compared to determine the efficiency of the reagents used and the effects of the step order on the fractionation of metal species. In all cases, a magnesium nitrate solution (MgNIT) was previously used to extract exchangeable forms. In the first procedure (I), the next extraction step was performed with sodium acetate buffer (NaOAc), as used on calcareous soils, to dissolve active calcium carbonate. Then trace metals bound to different forms of oxi-hydroxides (NH(2)OH, TAMOx and TAMAs fractions) were extracted before organic matter/sulfide oxidation with hydrogen peroxide at pH 2.0 in nitric acid medium (OMHyd). Finally, residual bound metals (RESID) in each procedure were extracted with a nitric-hydrofluoric-perchloric acid mixture. The second procedure (II) was the same as I, but without the NaOAc step, because of the absence of carbonate in the study soil. In procedure III, the NaOAc step was omitted and the oxidizable organic/sulfide fraction was extracted with sodium hypochlorite at pH 8.5 (OMOCl) before the reducible fractions. This study first showed that NaOAc may remove considerable amounts of metals (especially Mn and Zn) in other forms than exchangeable ones. Procedures II and III give similar results for Fe, Mn and Zn forms, which were mainly found in fractions of inorganic soil components, but not for Cu and Pb. Copper distribution was affected by the position of the oxidation step in the sequence. In procedure II, where the oxidation step (OMHyd) ended the sequence, Cu was mainly recovered in the TAMOx fraction. However, in procedure III, where the oxidation step (OMOCl) preceded the NH(2)OH, TAMOx and TAMAs steps, Cu was found in both OMOCl and TAMOx fractions. LEAD DISTRIBUTION VARIED WITH OXIDATION REAGENT: it was partly removed in the OMHyd fraction of procedures I and II, and to a much lower extent in the OMOCl fraction of procedure III, probably due to the alkaline pH of the reagent in the latter case.
PMID: 12677342

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