Standard Reference Material of Orchard Leaves
果树叶标样
1 Scope of Application
This leaf sample (red star apple) is in possession of the standard reference value of the contents of such mineral elements as nitrogen, phosphorus, potassium, calcium, magnesium, ferrum, copper, manganese, zinc and boron, which may be used to verified the accuracy of the analysis result for the above-mentioned ten elements, as well as used in calibration instrument and for the inspection or establishment of new methods.
2 Preparation
In the middle of June, 1982, 30,000 pieces of red star apple leaves had been sampled from the Chang Yang orchard in the suburb of Beijing. After the process of washing, drying and pulverizing as well as being sieved and mixed repeatedly for three times, an uniform sample of 4 kg had been obtained and then been sub-packaged in 12 1000mL polyethylene plastic bottles.
The leaf sample was dried for 12h in a 85℃ drying oven within the plastic bottle and radiated with Cobalt-60 gamma-ray 4.9 Mrad by Atomic Energy Research Institute of Chinese Academy of Agricultural Sciences after sealing the cap; then it was sealed up and stored in dark places under room temperature (10 ~ 30℃).
3 Fineness and Uniformity
3.1 Fineness: more than 98 % of the particles shall pass through 60-mesh and 50 % of the particles shall pass through 160-mesh.
3.2 Uniformity: take 3 sub-samples from each of the 12 plastic bottles storing the leaf samples in order to repeat for 3 times; carry out the determination of nitrogen and phosphorus contents and check the obtained data with F; if there is no significant difference in the result, then the sample is proved to be uniform.
4 Standard Reference Value for the Standard Reference Material of Orchard Leaves
The analyzing and value setting shall be carried out through such ten analysis techniques as Kjeldahl method, Dumas method, atomic absorption method, neutron activation analysis method, inductively coupled plasma atomic emission spectrometry and the like by domestic and foreign laboratories with certain analytic level; several laboratories shall take similar standard substance of the U.S. as reference.
The value setting for each element shall be carried out with more than two analysis methods which are of different principles and there shall be provided with analysis data from more than six laboratories. After being treated with statistic methods, the average value, 95% confidence limit and coefficient of variation are listed in the following table.
Standard Reference Value for the Standard Reference Material of Orchard Leaves
Element data number n Average value of content 95% confidence limit Coefficient of variation, %
Invariable element (%dry basis*)
N
P
K
Ca
Mg 13
9
14
14
12 2.42
0.176
1.61
1.48
0.471 2.36~2.48
0.166~0.186
1.51~1.71
1.42~1.54
0.433~0.509 3.9
8.1
10.8
6.7
11.5
Trace element (mg/kg dry basis*)
Fe
Cu
Mn
Zn
B 11
10
10
11
7 117
31.8
25.2
14.8
36.1 108~126
29.5~34.1
24.6~25.8
14.1~15.5
32.8~39.4 12.0
10.0
3.5
6.7
10.2
*Counted by dry basis dried for 4h at 85℃. .
5 Packaging, Preservation and Application Method of Standard Reference Material
This standard reference material is packaged within plastic bottles with 20g in each bottle; the bottle neck is equipped with plastic inner cover and the outer cover is sealed with plastic cement.
5.1 This standard reference material shall be preserved in dark and dry places with the temperature not exceeding 30℃.
5.2 Prior to use, the standard reference material shall be mixed uniformly again and dried for 4 h in a 85℃ drying oven; then it shall be placed in a dryer and weighed after cooling.
5.3 The amount of standard reference material for general analysis shall not be less than 0.5g.
6 Supply Organization
Mineral Nutrition Research Center of College of Horticulture, China Agricultural University.
1 Scope of Application
2 Preparation
3 Fineness and Uniformity
4 Standard Reference Value for the Standard Reference Material of Orchard Leaves
5 Packaging, Preservation and Application Method of Standard Reference Material
6 Supply Organization
Appendix A Analytical Method and Determination Organization of Standard Leaf Sample of Orchards (Supplement)
Standard Reference Material of Orchard Leaves
果树叶标样
1 Scope of Application
This leaf sample (red star apple) is in possession of the standard reference value of the contents of such mineral elements as nitrogen, phosphorus, potassium, calcium, magnesium, ferrum, copper, manganese, zinc and boron, which may be used to verified the accuracy of the analysis result for the above-mentioned ten elements, as well as used in calibration instrument and for the inspection or establishment of new methods.
2 Preparation
In the middle of June, 1982, 30,000 pieces of red star apple leaves had been sampled from the Chang Yang orchard in the suburb of Beijing. After the process of washing, drying and pulverizing as well as being sieved and mixed repeatedly for three times, an uniform sample of 4 kg had been obtained and then been sub-packaged in 12 1000mL polyethylene plastic bottles.
The leaf sample was dried for 12h in a 85℃ drying oven within the plastic bottle and radiated with Cobalt-60 gamma-ray 4.9 Mrad by Atomic Energy Research Institute of Chinese Academy of Agricultural Sciences after sealing the cap; then it was sealed up and stored in dark places under room temperature (10 ~ 30℃).
3 Fineness and Uniformity
3.1 Fineness: more than 98 % of the particles shall pass through 60-mesh and 50 % of the particles shall pass through 160-mesh.
3.2 Uniformity: take 3 sub-samples from each of the 12 plastic bottles storing the leaf samples in order to repeat for 3 times; carry out the determination of nitrogen and phosphorus contents and check the obtained data with F; if there is no significant difference in the result, then the sample is proved to be uniform.
4 Standard Reference Value for the Standard Reference Material of Orchard Leaves
The analyzing and value setting shall be carried out through such ten analysis techniques as Kjeldahl method, Dumas method, atomic absorption method, neutron activation analysis method, inductively coupled plasma atomic emission spectrometry and the like by domestic and foreign laboratories with certain analytic level; several laboratories shall take similar standard substance of the U.S. as reference.
The value setting for each element shall be carried out with more than two analysis methods which are of different principles and there shall be provided with analysis data from more than six laboratories. After being treated with statistic methods, the average value, 95% confidence limit and coefficient of variation are listed in the following table.
Standard Reference Value for the Standard Reference Material of Orchard Leaves
Element data number n Average value of content 95% confidence limit Coefficient of variation, %
Invariable element (%dry basis*)
N
P
K
Ca
Mg 13
9
14
14
12 2.42
0.176
1.61
1.48
0.471 2.36~2.48
0.166~0.186
1.51~1.71
1.42~1.54
0.433~0.509 3.9
8.1
10.8
6.7
11.5
Trace element (mg/kg dry basis*)
Fe
Cu
Mn
Zn
B 11
10
10
11
7 117
31.8
25.2
14.8
36.1 108~126
29.5~34.1
24.6~25.8
14.1~15.5
32.8~39.4 12.0
10.0
3.5
6.7
10.2
*Counted by dry basis dried for 4h at 85℃. .
5 Packaging, Preservation and Application Method of Standard Reference Material
This standard reference material is packaged within plastic bottles with 20g in each bottle; the bottle neck is equipped with plastic inner cover and the outer cover is sealed with plastic cement.
5.1 This standard reference material shall be preserved in dark and dry places with the temperature not exceeding 30℃.
5.2 Prior to use, the standard reference material shall be mixed uniformly again and dried for 4 h in a 85℃ drying oven; then it shall be placed in a dryer and weighed after cooling.
5.3 The amount of standard reference material for general analysis shall not be less than 0.5g.
6 Supply Organization
Mineral Nutrition Research Center of College of Horticulture, China Agricultural University.
Contents of GB 7171-1987
1 Scope of Application
2 Preparation
3 Fineness and Uniformity
4 Standard Reference Value for the Standard Reference Material of Orchard Leaves
5 Packaging, Preservation and Application Method of Standard Reference Material
6 Supply Organization
Appendix A Analytical Method and Determination Organization of Standard Leaf Sample of Orchards (Supplement)
