The Study of Photogradation of Dichlorvos Pesticide Residues in Vegetables

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This paper studies the photodegradation of dichlorvos pesticide residues in vegetables by ultraviolet excimer and direct sunlight. It was observed that the degradation of pesticide residues in vegetables conforms to the dynamic equation for pesticide degradation. The decomposition rate of the same concentration of organophosphorus pesticide was found to vary in different vegetables. This is attributed mainly to the pigments because chlorophyll pigments in different vegetables can stimulate the dichlorvos photodegradation. Through the uv excimer, the residual pesticide in the vegetable can be effectively removed in a short period of time, while the appears to be no adverse affects from this process. Therefore, it is possible to achieve a selective degradation of residual pesticides in vegetables through the use of uv excimers.

Info:

Periodical:

Advanced Materials Research (Volumes 287-290)

Edited by:

Jinglong Bu, Pengcheng Wang, Liqun Ai, Xiaoming Sang, Yungang Li

Pages:

1779-1788

DOI:

10.4028/www.scientific.net/AMR.287-290.1779

Citation:

T. B. Liu et al., "The Study of Photogradation of Dichlorvos Pesticide Residues in Vegetables", Advanced Materials Research, Vols. 287-290, pp. 1779-1788, 2011

Online since:

July 2011

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Price:

$35.00

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DOI: 10.1002/ps.2780030511

[77] 71±6. 24.

[8] 03 5.

[85] 66±8. 95.

[10] 45 10 106. 19±7. 48.

[7] 04 spinach 1.

[75] 86±9. 96.

[13] 13 5.

[83] 47±11. 52.

[13] 8 10 102. 79±10. 35.

[10] 07 Table2. Photolytic kinetics of dichlorvos in vegetables under different light sources Sample Types of light Fitted dynamic equation Correlation coefficients (R2) Photodegradation rate constant K(10-2) Half-life times T1/2 Ct = C0·e-kt Cabbage Spinach Sunlight Excimer uv Sunlight Excimer uv Ct =100e-0. 0337t Ct=103. 45 e-0. 0059t Ct =99. 601e-0. 0383t Ct =100. 99e-0. 006t.

9718.

9524.

9605.

9617.

[3] 37 h-1.

59 s-1.

[3] 83 h-1.

6s-1.

[20] 6h 117. 49s.

[18] 1h 115. 53s Note: Sunlight intensity 50000~80000 Lx, The excimer ultraviolet intensity 100000Lx, Dichlorvos add doses 10mg/kg. Table 3. Effects of different added doses on photodegradation of dichlorvos in vegetables Sample Processing (mg/ kg) Fitted dynamic equation Ct = C0·e-kt Correlation coefficients (R2) Photodegradation rate constant K(10-2s-1) Half-life T1/2(s) Cabbage 1mg/kg 5mg/kg 10mg/kg Ct=102. 82 e-0. 006t Ct=99. 128e-0. 0061t Ct=103. 45 e-0. 0059t.

DOI: 10.21275/v5i5.nov163413

9639.

9496.

9524.

6.

61.

59 115. 53 113. 64 117. 49 Note: ultraviolet excimer intensity 100000Lx.

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