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Copyright of Food & Fermentation Industries is the property of Food & Fermentation Industries and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Guangdong Agricultural Sciences is the property of South China Agricultural University, Guangdong Academy of Agricultural Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Modern Food Science & Technology is the property of Editorial Office of Modern Food Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A residual analysis method for mefentrifluconazole in banana and mango was established using ultra high performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) detection technology. The field trial was conducted in banana and mango at six sites during one year according to NY/T 788-2018 the "Guideline for the Testing of Pesticide Residues in Crops" to study the degradation dynamics and residual distribution of mefentrifluconazole. After the application of the formulation of mefentrifluconazole 400 g/L suspension concentration (SC) on banana and mango crops, fruit samples were extracted with acetonitrile, purified with combined adsorbents of GCB and C18, and analyzed by UPLC-MS/MS. The results showed that at four spiked levels of 0.001-1 mg/kg, the average recovery of mefentrifluconazole in whole banana and flesh was 83%-93% with the relative standard deviation (RSD) 2.3% to 5.9%, and the average recovery of mefentrifluconazole in whole mango and flesh was 82%-91% with the RSD 2.9% to 6.0%, respectively; and the limit of quantification (LOQ) was 0.001 mg/kg. The field trials in banana showed that, under the condition of applying mefentrifluconazole 400 g/L SC at dosage of 133.3 mg/kg for 3 times with application interval of 7-10 days, the residues of mefentrifluconazole at 21 and 28 days after the last application were 0.03-0.09 mg/kg in whole banana and <0.001-0.004 mg/kg in the flesh. In the field trials of mango, under the condition of applying mefentrifluconazole 400 g/L SC at dosage of 160 mg/kg for 3 times with application interval of 7-10 days, residues of mefentrifluconazole were 0.04-0.28 mg/kg in whole mango and 0.001-0.003 mg/kg in the flesh at 14 and 21 days after the last application. The research results can provide a reference for guiding the scientific and rational use of mefentrifluconazole in banana and mango, as well as for the establishment of its maximum residue limit (MRL) values. [ABSTRACT FROM AUTHOR]

Copyright of Bulletin of Botanical Research is the property of Bulletin of Botanical Research Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Pesticides, plant protection machinery and application technology are the three pillars of plant chemical protection, of which application technology is the key link between pesticides and plant protection machinery. It is the "last mile" from pesticide research to field application. The scientific use of pesticides is not a simple pharmacological problem of pesticide selection and application dosage, but involves plant protection, agricultural mechanics, meteorology and other disciplines, forming an interdisciplinary combination of systemic engineering. This paper presents a review of pesticide droplet atomization and movement characteristics, deposition and distribution status, loss and drift behavior, and the relationship between pest behavior and pesticide droplet atomization movement and deposition distribution. The purpose of summarizing the theoretical and practical experiences in these areas is to improve the standards and quality of plant protection machinery, pesticide utilization, control effects and food safety, as well as reducing the negative impacts of pesticides. In addition, these theories and practices provide technical methods and equipment support to improve the quality and efficiency of crops and to protect agroecological and human environments. [ABSTRACT FROM AUTHOR]

Copyright of Modern Food Science & Technology is the property of Editorial Office of Modern Food Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Organosilicon adjuvant Silwet stik and vegetable oil adjuvant Maisi were selected to conduct field experiments with thiamethoxam to verify the preventive effect on cowpea thrips and residual behavior. Dissipation dynamic and residues of recommended application dose 75, 67.5, 60, and 52.5 g a.i/hm² of 25% thiamethoxam water dispersible granules (WG) with two different adjuvants were compared respectively and the preventive effect of 5 and 7 days after the last spray was investigated. The cowpea samples were extracted by acetonitrile, purified with primary secondary amine (PSA), and detected using high performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS). The results of field tests indicated that the initial deposition of thiamethoxam on cowpea were significantly increased by 8.84% and 6.58% respectively when the adjuvant 0.4% Silwet stik or 0.5% Maisi was added. The control effect against cowpea thrips of 25% thiamethoxam WG added with the two adjuvants above were significantly higher than that without adjuvant 7 days after treatments. Five days after treatments, the addition of adjuvant Silwet stik or Maisi increased preventive effect by 4.04%-8.55% and 10.37%-12.25% respectively, while the recommended application dose of thiamethoxam was reduced by 10%-30%. The results showed that the adjuvant treatments increased the deposition of thiamethoxam on cowpea, which would benefit the synergistic effect of pesticide, and improved control effect on thrips. The study provides evidence for the synergistic control effect of adjuvants and the scientific use of thiamethoxam against cowpea thrips. [ABSTRACT FROM AUTHOR]

An analytical method was established for simultaneous determination of chlorantraniliprole, cyantraniliprole and its metabolite J9Z38 in litchi by high performance liquid chromatography coupled to tandem mass spectrometry (HPLC-MS/MS) combined with a modified QuEChERS procedure. The target compounds were extracted from the samples with acetonitrile and then cleaned up with primary secondary amine (PSA) and octadecylsilane (C18). The analytes were separated on a C18 column using V (formic acid aqueous solution) : V (acetonitrile)=15 : 85 as mobile phase and analyzed in multiple reaction monitoring (MRM) mode with positive electrospray ionization (ESI+ ). Quantitative analysis was performed by external standard method using matrix-matched calibration curves. The results showed that the linearity of the target compounds was good (r >0.99) in the range of 0.005-1 mg/L. The limits of quantification (LOQs) were 0.000 5-0.01 mg/kg. The average recoveries of the three pesticides in litchi (whole fruit and pulp) ranged from 76% to 98% at the spiked levels of 0.000 5-0.5 mg/kg, with the relative standard deviations of 2.5% to 9.6%. The method was applied for the detection of twenty commercial litchi samples in Guangzhou City. The results showed that the residues of chlorantraniliprole were 0.001-0.01 mg/kg, and neither cyantraniliprole nor its metabolite J9Z38 were found. The proposed method is convenient, effective and rapid, and is suitable for the simultaneous determination of chlorantraniliprole, cyantraniliprole and its metabolite in litchi. [ABSTRACT FROM AUTHOR]

A sensitive method for determination of spirotetramat and its metabolites and chlorantraniliprole in longan（Dimocarpus longan Lour.） were developed based on high performance liquid chromatography-tandem mass spectrometry（HPLC-MS/MS） technique. The terminal residues of spirotetramat and chlorantraniliprole in longan under field conditions were studied in 6 experimental sites in 2018. The samples were extracted with acetonitrile, cleaned up with PSA, detected by HPLCMS/MS, and quantified by external standard method. The mean recoveries of spirotetramat and its four metabolites and chlorantraniliprole in longan whole fruit and longan pulp were 83%-103%, and 87%-92%, respectively, at the three spiking levels from 0.01 to 1 mg/kg with relative standard deviations（RSDs） of 2.3%-8.7%, and 3.3%-6.3%. The limits of quantitation（LOQs） of spirotetramat and its four metabolites and chlorantraniliprole was 0.01 mg/kg. In the field trials, 22.4% spirotetramat SC and 5%chlorantraniliprole SC were applied at the dosage of 60 and 50 mg/kg for two times with the interval 7-10 d, respectively. The results showed that terminal residues of spirotetramat and chlorantraniliprole in longan whole fruit were 0.30-1.14 and 0.06-0.29 mg/kg, respectively, at 14 d after application, and were <0.05 and < 0.01 mg/kg, respectively in longan pulp. This study would be helpful to guide scientific and efficient utilization of these pesticides. Because of the absence of maximum residue limits（MRLs） value of spirotetramat and chlorantraniliprole in longan, these results could provide data to facilitate the setting of longan MRL. [ABSTRACT FROM AUTHOR]

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chinese Journal of Pesticide Science / Nongyaoxue Xuebao is the property of Chinese Journal of Pesticide Science and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chinese Journal of Pesticide Science / Nongyaoxue Xuebao is the property of Chinese Journal of Pesticide Science and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chinese Journal of Pesticide Science / Nongyaoxue Xuebao is the property of Chinese Journal of Pesticide Science and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The critical surface tension (CST) of litchi leaf, as well as the surface free energy (SFE), surface tension, static contact angle and dynamic contact angle in 0-60 s of diluted solution of 10% difenoconazole water dispersible granule (WG) were determined by using contact angle measuring device and automatic surface tension meter. Effects on wettability of difenoconazole WG with adjuvants (0.4% silwet stik and 0.2% as 100) on litchi leaf surface were also investigated.The results showed that the SFE value of the adaxial surface of litchi leaf was about 23.74 mJ/m2, while the SFE value of the abaxial surface was about 11.89 mJ/m2,and the dispersion component was dominant.The surface tension of 500-fold dilution of 10% difenoconazole WG with 0.4% silwet stik on litchi leaf was 21.90 mN/m, while the CST of lichi leaf was 22.64 mN/m. The contact angle of WG’s 500-fold dilution with silwet stik declined the fastest during 0-10 s.The results suggested that the adaxial surface of litchi leaf was more wettable than the abaxial surface. When 10% difenoconazole WG was applied to lichi trees,the best performance was accheived by 500-fold dilution with 0.4% silwet stik adjuvant. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Pesticide Science / Nongyaoxue Xuebao is the property of Chinese Journal of Pesticide Science and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The fractional order model of thermocouple is used to study the dynamic characteristics of thermocouple. In dynamic system temperature measurement, a delay of temperature response exists when the thermocouple is used to measure the transient temperature. The process of measurement is a time-delay process or genetic process. When thermocouple wires come into contact with an object being measured, the heat transfer occurs through the wires. The temperature on measuring junction results from the heat transfer between medium and measuring junction and the heat conduction between measuring junction and wires. A fractional order model of semi-infinite solid heat conduction is established based on the theory of fractional calculus. The proposed model describes the heat transfer between the measuring junction and the measured medium, including the heat transfer between the measuring junction and the wire. A fractional order transfer function is obtained by fractional Laplace transform. The transfer function describes the time lag of thermal inertia and the phase delay of thermal diffusion. An experimental system for measuring the surface temperature by thermocouple is built to collect the input and output data of thermocouple under the step perturbationed. Based on measured input and output data, the parameters and order of fractional order transfer function are estimated by using the new Luus-Jaakola algorithm. The experimental and calculated results show that the fitting results of variable fractional order transfer function are better than those of invariable fractional order transfer function. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Applied Ecology / Yingyong Shengtai Xuebao is the property of Chinese Journal of Applied Ecology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chinese Journal of Pesticide Science / Nongyaoxue Xuebao is the property of Chinese Journal of Pesticide Science and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)